Commit Graph

8307 Commits

Author SHA1 Message Date
Andrea Gelmini
52042d8e82 btrfs: Fix typos in comments and strings
The typos accumulate over time so once in a while time they get fixed in
a large patch.

Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:50 +01:00
Johannes Thumshirn
1690dd41e0 btrfs: improve error handling of btrfs_add_link
In the error handling block, err holds the return value of either
btrfs_del_root_ref() or btrfs_del_inode_ref() but it hasn't been checked
since it's introduction with commit fe66a05a06 (Btrfs: improve error
handling for btrfs_insert_dir_item callers) in 2012.

If the error handling in the error handling fails, there's not much left
to do and the abort either happened earlier in the callees or is
necessary here.

So if one of btrfs_del_root_ref() or btrfs_del_inode_ref() failed, abort
the transaction, but still return the original code of the failure
stored in 'ret' as this will be reported to the user.

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:50 +01:00
Filipe Manana
34a28e3d77 Btrfs: use generic_remap_file_range_prep() for cloning and deduplication
Since cloning and deduplication are no longer Btrfs specific operations, we
now have generic code to handle parameter validation, compare file ranges
used for deduplication, clear capabilities when cloning, etc. This change
makes Btrfs use it, eliminating a lot of code in Btrfs and also fixing a
few bugs, such as:

1) When cloning, the destination file's capabilities were not dropped
   (the fstest generic/513 tests this);

2) We were not checking if the destination file is immutable;

3) Not checking if either the source or destination files are swap
   files (swap file support is coming soon for Btrfs);

4) System limits were not checked (resource limits and O_LARGEFILE).

Note that the generic helper generic_remap_file_range_prep() does start
and waits for writeback by calling filemap_write_and_wait_range(), however
that is not enough for Btrfs for two reasons:

1) With compression, we need to start writeback twice in order to get the
   pages marked for writeback and ordered extents created;

2) filemap_write_and_wait_range() (and all its other variants) only waits
   for the IO to complete, but we need to wait for the ordered extents to
   finish, so that when we do the actual reflinking operations the file
   extent items are in the fs tree. This is also important due to the fact
   that the generic helper, for the deduplication case, compares the
   contents of the pages in the requested range, which might require
   reading extents from disk in the very unlikely case that pages get
   invalidated after writeback finishes (so the file extent items must be
   up to date in the fs tree).

Since these reasons are specific to Btrfs we have to do it in the Btrfs
code before calling generic_remap_file_range_prep(). This also results
in a simpler way of dealing with existing delalloc in the source/target
ranges, specially for the deduplication case where we used to lock all
the pages first and then if we found any dealloc for the range, or
ordered extent, we would unlock the pages trigger writeback and wait for
ordered extents to complete, then lock all the pages again and check if
deduplication can be done. So now we get a simpler approach: lock the
inodes, then trigger writeback and then wait for ordered extents to
complete.

So make btrfs use generic_remap_file_range_prep() (XFS and OCFS2 use it)
to eliminate duplicated code, fix a few bugs and benefit from future bug
fixes done there - for example the recent clone and dedupe bugs involving
reflinking a partial EOF block got a counterpart fix in the generic
helper, since it affected all filesystems supporting these operations,
so we no longer need special checks in Btrfs for them.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:50 +01:00
Nikolay Borisov
61ed3a144a btrfs: Refactor main loop in extent_readpages
extent_readpages processes all pages in the readlist in batches of 16,
this is implemented by a single for loop but thanks to an if condition
the loop does 2 things based on whether we've filled the batch or not.
Additionally due to the structure of the code there is an additional
check which deals with partial batches.

Streamline all of this by explicitly using two loops. The outter one is
used to process all pages while the inner one just fills in the batch
of 16 (currently). Due to this new structure the code guarantees that
all pages are processed in the loop hence the code to deal with any
leftovers is eliminated.

This also enable the compiler to inline __extent_readpages:

	./scripts/bloat-o-meter fs/btrfs/extent_io.o extent_io.for

	add/remove: 0/1 grow/shrink: 1/0 up/down: 660/-820 (-160)
	Function                                     old     new   delta
	extent_readpages                             476    1136    +660
	__extent_readpages                           820       -    -820
	Total: Before=44315, After=44155, chg -0.36%

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:49 +01:00
Nikolay Borisov
15c8276302 btrfs: Remove 1st shrink/grow phase from balance
The first step of the rebalance process ensures there is 1MiB free on
each device. This number seems rather small. And in fact when talking to
the original authors their opinions were:

"man that's a little bonkers"
"i don't think we even need that code anymore"
"I think it was there to make sure we had room for the blank 1M at the
beginning. I bet it goes all the way back to v0"
"we just don't need any of that tho, i say we just delete it"

Clearly, this piece of code has lost its original intent throughout the
years. It doesn't really bring any real practical benefits to the
relocation process.

Additionally, this patch makes the balance process more lightweight by
removing a pair of shrink/grow operations which are rather expensive for
heavily populated filesystems. This is mainly due to shrink requiring
relocating block groups, involving heavy use of the btree.

The intermediate shrink/grow can fail and leave the filesystem in a
middle state that would need to be changed back by the user.

Suggested-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:49 +01:00
Filipe Manana
be6821f82c Btrfs: send, fix race with transaction commits that create snapshots
If we create a snapshot of a snapshot currently being used by a send
operation, we can end up with send failing unexpectedly (returning
-ENOENT error to user space for example). The following diagram shows
how this happens.

            CPU 1                                   CPU2                                CPU3

 btrfs_ioctl_send()
  (...)
                                     create_snapshot()
                                      -> creates snapshot of a
                                         root used by the send
                                         task
                                      btrfs_commit_transaction()
                                       create_pending_snapshot()
  __get_inode_info()
   btrfs_search_slot()
    btrfs_search_slot_get_root()
     down_read commit_root_sem

     get reference on eb of the
     commit root
      -> eb with bytenr == X

     up_read commit_root_sem

                                        btrfs_cow_block(root node)
                                         btrfs_free_tree_block()
                                          -> creates delayed ref to
                                             free the extent

                                       btrfs_run_delayed_refs()
                                        -> runs the delayed ref,
                                           adds extent to
                                           fs_info->pinned_extents

                                       btrfs_finish_extent_commit()
                                        unpin_extent_range()
                                         -> marks extent as free
                                            in the free space cache

                                      transaction commit finishes

                                                                       btrfs_start_transaction()
                                                                        (...)
                                                                        btrfs_cow_block()
                                                                         btrfs_alloc_tree_block()
                                                                          btrfs_reserve_extent()
                                                                           -> allocates extent at
                                                                              bytenr == X
                                                                          btrfs_init_new_buffer(bytenr X)
                                                                           btrfs_find_create_tree_block()
                                                                            alloc_extent_buffer(bytenr X)
                                                                             find_extent_buffer(bytenr X)
                                                                              -> returns existing eb,
                                                                                 which the send task got

                                                                        (...)
                                                                         -> modifies content of the
                                                                            eb with bytenr == X

    -> uses an eb that now
       belongs to some other
       tree and no more matches
       the commit root of the
       snapshot, resuts will be
       unpredictable

The consequences of this race can be various, and can lead to searches in
the commit root performed by the send task failing unexpectedly (unable to
find inode items, returning -ENOENT to user space, for example) or not
failing because an inode item with the same number was added to the tree
that reused the metadata extent, in which case send can behave incorrectly
in the worst case or just fail later for some reason.

Fix this by performing a copy of the commit root's extent buffer when doing
a search in the context of a send operation.

CC: stable@vger.kernel.org # 4.4.x: 1fc28d8e2e: Btrfs: move get root out of btrfs_search_slot to a helper
CC: stable@vger.kernel.org # 4.4.x: f9ddfd0592: Btrfs: remove unused check of skip_locking
CC: stable@vger.kernel.org # 4.4.x
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:49 +01:00
Filipe Manana
827aa18e7b Btrfs: use nofs context when initializing security xattrs to avoid deadlock
When initializing the security xattrs, we are holding a transaction handle
therefore we need to use a GFP_NOFS context in order to avoid a deadlock
with reclaim in case it's triggered.

Fixes: 39a27ec100 ("btrfs: use GFP_KERNEL for xattr and acl allocations")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:49 +01:00
Josef Bacik
0568e82dbe btrfs: run delayed items before dropping the snapshot
With my delayed refs patches in place we started seeing a large amount
of aborts in __btrfs_free_extent:

 BTRFS error (device sdb1): unable to find ref byte nr 91947008 parent 0 root 35964  owner 1 offset 0
 Call Trace:
  ? btrfs_merge_delayed_refs+0xaf/0x340
  __btrfs_run_delayed_refs+0x6ea/0xfc0
  ? btrfs_set_path_blocking+0x31/0x60
  btrfs_run_delayed_refs+0xeb/0x180
  btrfs_commit_transaction+0x179/0x7f0
  ? btrfs_check_space_for_delayed_refs+0x30/0x50
  ? should_end_transaction.isra.19+0xe/0x40
  btrfs_drop_snapshot+0x41c/0x7c0
  btrfs_clean_one_deleted_snapshot+0xb5/0xd0
  cleaner_kthread+0xf6/0x120
  kthread+0xf8/0x130
  ? btree_invalidatepage+0x90/0x90
  ? kthread_bind+0x10/0x10
  ret_from_fork+0x35/0x40

This was because btrfs_drop_snapshot depends on the root not being
modified while it's dropping the snapshot.  It will unlock the root node
(and really every node) as it walks down the tree, only to re-lock it
when it needs to do something.  This is a problem because if we modify
the tree we could cow a block in our path, which frees our reference to
that block.  Then once we get back to that shared block we'll free our
reference to it again, and get ENOENT when trying to lookup our extent
reference to that block in __btrfs_free_extent.

This is ultimately happening because we have delayed items left to be
processed for our deleted snapshot _after_ all of the inodes are closed
for the snapshot.  We only run the delayed inode item if we're deleting
the inode, and even then we do not run the delayed insertions or delayed
removals.  These can be run at any point after our final inode does its
last iput, which is what triggers the snapshot deletion.  We can end up
with the snapshot deletion happening and then have the delayed items run
on that file system, resulting in the above problem.

This problem has existed forever, however my patches made it much easier
to hit as I wake up the cleaner much more often to deal with delayed
iputs, which made us more likely to start the snapshot dropping work
before the transaction commits, which is when the delayed items would
generally be run.  Before, generally speaking, we would run the delayed
items, commit the transaction, and wakeup the cleaner thread to start
deleting snapshots, which means we were less likely to hit this problem.
You could still hit it if you had multiple snapshots to be deleted and
ended up with lots of delayed items, but it was definitely harder.

Fix for now by simply running all the delayed items before starting to
drop the snapshot.  We could make this smarter in the future by making
the delayed items per-root, and then simply drop any delayed items for
roots that we are going to delete.  But for now just a quick and easy
solution is the safest.

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:49 +01:00
Josef Bacik
83354f0772 btrfs: catch cow on deleting snapshots
When debugging some weird extent reference bug I suspected that we were
changing a snapshot while we were deleting it, which could explain my
bug.  This was indeed what was happening, and this patch helped me
verify my theory.  It is never correct to modify the snapshot once it's
being deleted, so mark the root when we are deleting it and make sure we
complain about it when it happens.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:48 +01:00
Qu Wenruo
01e0da4885 btrfs: extent-tree: cleanup one-shot usage of @blocksize in do_walk_down
@blocksize variable in do_walk_down() is only used once, really no need
to declare it.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:48 +01:00
Filipe Manana
7c3c7cb99c Btrfs: scrub, move setup of nofs contexts higher in the stack
Since scrub workers only do memory allocation with GFP_KERNEL when they
need to perform repair, we can move the recent setup of the nofs context
up to scrub_handle_errored_block() instead of setting it up down the call
chain at insert_full_stripe_lock() and scrub_add_page_to_wr_bio(),
removing some duplicate code and comment. So the only paths for which a
scrub worker can do memory allocations using GFP_KERNEL are the following:

 scrub_bio_end_io_worker()
   scrub_block_complete()
     scrub_handle_errored_block()
       lock_full_stripe()
         insert_full_stripe_lock()
           -> kmalloc with GFP_KERNEL

  scrub_bio_end_io_worker()
    scrub_block_complete()
      scrub_handle_errored_block()
        scrub_write_page_to_dev_replace()
          scrub_add_page_to_wr_bio()
            -> kzalloc with GFP_KERNEL

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:48 +01:00
David Sterba
0e94c4f45d btrfs: scrub: move scrub_setup_ctx allocation out of device_list_mutex
The scrub context is allocated with GFP_KERNEL and called from
btrfs_scrub_dev under the fs_info::device_list_mutex. This is not safe
regarding reclaim that could try to flush filesystem data in order to
get the memory. And the device_list_mutex is held during superblock
commit, so this would cause a lockup.

Move the alocation and initialization before any changes that require
the mutex.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:48 +01:00
David Sterba
92f7ba434f btrfs: scrub: pass fs_info to scrub_setup_ctx
We can pass fs_info directly as this is the only member of btrfs_device
that's bing used inside scrub_setup_ctx.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:48 +01:00
Josef Bacik
28bad21257 btrfs: fix truncate throttling
We have a bunch of magic to make sure we're throttling delayed refs when
truncating a file.  Now that we have a delayed refs rsv and a mechanism
for refilling that reserve simply use that instead of all of this magic.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:47 +01:00
Josef Bacik
db2462a6ad btrfs: don't run delayed refs in the end transaction logic
Over the years we have built up a lot of infrastructure to keep delayed
refs in check, mostly by running them at btrfs_end_transaction() time.
We have a lot of different maths we do to figure out how much, if we
should do it inline or async, etc.  This existed because we had no
feedback mechanism to force the flushing of delayed refs when they
became a problem.  However with the enospc flushing infrastructure in
place for flushing delayed refs when they put too much pressure on the
enospc system we have this problem solved.  Rip out all of this code as
it is no longer needed.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:47 +01:00
Josef Bacik
64403612b7 btrfs: rework btrfs_check_space_for_delayed_refs
Now with the delayed_refs_rsv we can now know exactly how much pending
delayed refs space we need.  This means we can drastically simplify
btrfs_check_space_for_delayed_refs by simply checking how much space we
have reserved for the global rsv (which acts as a spill over buffer) and
the delayed refs rsv.  If our total size is beyond that amount then we
know it's time to commit the transaction and stop any more delayed refs
from being generated.

With the introduction of dealyed_refs_rsv infrastructure, namely
btrfs_update_delayed_refs_rsv we now know exactly how much pending
delayed refs space is required.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:47 +01:00
Josef Bacik
413df7252d btrfs: add new flushing states for the delayed refs rsv
A nice thing we gain with the delayed refs rsv is the ability to flush
the delayed refs on demand to deal with enospc pressure.  Add states to
flush delayed refs on demand, and this will allow us to remove a lot of
ad-hoc work around checking to see if we should commit the transaction
to run our delayed refs.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:47 +01:00
Josef Bacik
4c8edbc75c btrfs: update may_commit_transaction to use the delayed refs rsv
Any space used in the delayed_refs_rsv will be freed up by a transaction
commit, so instead of just counting the pinned space we also need to
account for any space in the delayed_refs_rsv when deciding if it will
make a different to commit the transaction to satisfy our space
reservation.  If we have enough bytes to satisfy our reservation ticket
then we are good to go, otherwise subtract out what space we would gain
back by committing the transaction and compare that against the pinned
space to make our decision.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:47 +01:00
Josef Bacik
ba2c4d4e3b btrfs: introduce delayed_refs_rsv
Traditionally we've had voodoo in btrfs to account for the space that
delayed refs may take up by having a global_block_rsv.  This works most
of the time, except when it doesn't.  We've had issues reported and seen
in production where sometimes the global reserve is exhausted during
transaction commit before we can run all of our delayed refs, resulting
in an aborted transaction.  Because of this voodoo we have equally
dubious flushing semantics around throttling delayed refs which we often
get wrong.

So instead give them their own block_rsv.  This way we can always know
exactly how much outstanding space we need for delayed refs.  This
allows us to make sure we are constantly filling that reservation up
with space, and allows us to put more precise pressure on the enospc
system.  Instead of doing math to see if its a good time to throttle,
the normal enospc code will be invoked if we have a lot of delayed refs
pending, and they will be run via the normal flushing mechanism.

For now the delayed_refs_rsv will hold the reservations for the delayed
refs, the block group updates, and deleting csums.  We could have a
separate rsv for the block group updates, but the csum deletion stuff is
still handled via the delayed_refs so that will stay there.

Historical background:

The global reserve has grown to cover everything we don't reserve space
explicitly for, and we've grown a lot of weird ad-hoc heuristics to know
if we're running short on space and when it's time to force a commit.  A
failure rate of 20-40 file systems when we run hundreds of thousands of
them isn't super high, but cleaning up this code will make things less
ugly and more predictible.

Thus the delayed refs rsv.  We always know how many delayed refs we have
outstanding, and although running them generates more we can use the
global reserve for that spill over, which fits better into it's desired
use than a full blown reservation.  This first approach is to simply
take how many times we're reserving space for and multiply that by 2 in
order to save enough space for the delayed refs that could be generated.
This is a niave approach and will probably evolve, but for now it works.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com> # high-level review
[ added background notes from the cover letter ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:46 +01:00
Josef Bacik
158ffa364b btrfs: only track ref_heads in delayed_ref_updates
We use this number to figure out how many delayed refs to run, but
__btrfs_run_delayed_refs really only checks every time we need a new
delayed ref head, so we always run at least one ref head completely no
matter what the number of items on it.  Fix the accounting to only be
adjusted when we add/remove a ref head.

In addition to using this number to limit the number of delayed refs
run, a future patch is also going to use it to calculate the amount of
space required for delayed refs space reservation.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:46 +01:00
Josef Bacik
bedc661760 btrfs: cleanup extent_op handling
The cleanup_extent_op function actually would run the extent_op if it
needed running, which made the name sort of a misnomer.  Change it to
run_and_cleanup_extent_op, and move the actual cleanup work to
cleanup_extent_op so it can be used by check_ref_cleanup() in order to
unify the extent op handling.

Reviewed-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:46 +01:00
Josef Bacik
07c47775f4 btrfs: add cleanup_ref_head_accounting helper
We were missing some quota cleanups in check_ref_cleanup, so break the
ref head accounting cleanup into a helper and call that from both
check_ref_cleanup and cleanup_ref_head.  This will hopefully ensure that
we don't screw up accounting in the future for other things that we add.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:46 +01:00
Josef Bacik
d7baffdaf9 btrfs: add btrfs_delete_ref_head helper
We do this dance in cleanup_ref_head and check_ref_cleanup, unify it
into a helper and cleanup the calling functions.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:46 +01:00
Johannes Thumshirn
fdb1e12180 btrfs: use PAGE_ALIGNED instead of open-coding it
When using a 'var & (PAGE_SIZE - 1)' construct one is checking for a page
alignment and thus should use the PAGE_ALIGNED() macro instead of
open-coding it.

Convert all open-coded occurrences of PAGE_ALIGNED().

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:45 +01:00
Johannes Thumshirn
7073017aeb btrfs: use offset_in_page instead of open-coding it
Constructs like 'var & (PAGE_SIZE - 1)' or 'var & ~PAGE_MASK' can denote an
offset into a page.

So replace them by the offset_in_page() macro instead of open-coding it if
they're not used as an alignment check.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:45 +01:00
David Sterba
cb5583dd52 btrfs: dev-replace: open code trivial locking helpers
The dev-replace locking functions are now trivial wrappers around rw
semaphore that can be used directly everywhere. No functional change.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:45 +01:00
David Sterba
53176dde0a btrfs: dev-replace: remove custom read/write blocking scheme
After the rw semaphore has been added, the custom blocking using
::blocking_readers and ::read_lock_wq is redundant.

The blocking logic in __btrfs_map_block is replaced by extending the
time the semaphore is held, that has the same blocking effect on writes
as the previous custom scheme that waited until ::blocking_readers was
zero.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:45 +01:00
David Sterba
129827e300 btrfs: dev-replace: swich locking to rw semaphore
This is the first part of removing the custom locking and waiting scheme
used for device replace. It was probably copied from extent buffer
locking, but there's nothing that would require more than is provided by
the common locking primitives.

The rw spinlock protects waiting tasks counter in case of incompatible
locks and the waitqueue. Same as rw semaphore.

This patch only switches the locking primitive, for better
bisectability.  There should be no functional change other than the
overhead of the locking and potential sleeping instead of spinning when
the lock is contended.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:44 +01:00
David Sterba
ceb21a8db4 btrfs: reada: reorder dev-replace locks before radix tree preload
The device-replace read lock is going to use rw semaphore in followup
commits. The semaphore might sleep which is not possible in the radix
tree preload section. The lock nesting is now:

* device replace
  * radix tree preload
    * readahead spinlock

Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:44 +01:00
Nikolay Borisov
d1051d6ebf btrfs: Fix error handling in btrfs_cleanup_ordered_extents
Running btrfs/124 in a loop hung up on me sporadically with the
following call trace:

	btrfs           D    0  5760   5324 0x00000000
	Call Trace:
	 ? __schedule+0x243/0x800
	 schedule+0x33/0x90
	 btrfs_start_ordered_extent+0x10c/0x1b0 [btrfs]
	 ? wait_woken+0xa0/0xa0
	 btrfs_wait_ordered_range+0xbb/0x100 [btrfs]
	 btrfs_relocate_block_group+0x1ff/0x230 [btrfs]
	 btrfs_relocate_chunk+0x49/0x100 [btrfs]
	 btrfs_balance+0xbeb/0x1740 [btrfs]
	 btrfs_ioctl_balance+0x2ee/0x380 [btrfs]
	 btrfs_ioctl+0x1691/0x3110 [btrfs]
	 ? lockdep_hardirqs_on+0xed/0x180
	 ? __handle_mm_fault+0x8e7/0xfb0
	 ? _raw_spin_unlock+0x24/0x30
	 ? __handle_mm_fault+0x8e7/0xfb0
	 ? do_vfs_ioctl+0xa5/0x6e0
	 ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs]
	 do_vfs_ioctl+0xa5/0x6e0
	 ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe
	 ksys_ioctl+0x3a/0x70
	 __x64_sys_ioctl+0x16/0x20
	 do_syscall_64+0x60/0x1b0
	 entry_SYSCALL_64_after_hwframe+0x49/0xbe

This happens because during page writeback it's valid for
writepage_delalloc to instantiate a delalloc range which doesn't belong
to the page currently being written back.

The reason this case is valid is due to find_lock_delalloc_range
returning any available range after the passed delalloc_start and
ignoring whether the page under writeback is within that range.

In turn ordered extents (OE) are always created for the returned range
from find_lock_delalloc_range. If, however, a failure occurs while OE
are being created then the clean up code in btrfs_cleanup_ordered_extents
will be called.

Unfortunately the code in btrfs_cleanup_ordered_extents doesn't consider
the case of such 'foreign' range being processed and instead it always
assumes that the range OE are created for belongs to the page. This
leads to the first page of such foregin range to not be cleaned up since
it's deliberately missed and skipped by the current cleaning up code.

Fix this by correctly checking whether the current page belongs to the
range being instantiated and if so adjsut the range parameters passed
for cleaning up. If it doesn't, then just clean the whole OE range
directly.

Fixes: 524272607e ("btrfs: Handle delalloc error correctly to avoid ordered extent hang")
CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:44 +01:00
Lu Fengqi
3522e90301 btrfs: remove always true if branch in find_delalloc_range
The @found is always false when it comes to the if branch. Besides, the
bool type is more suitable for @found. Change the return value of the
function and its caller to bool as well.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:44 +01:00
Lu Fengqi
27a7ff554e btrfs: skip file_extent generation check for free_space_inode in run_delalloc_nocow
The test case btrfs/001 with inode_cache mount option will encounter the
following warning:

  WARNING: CPU: 1 PID: 23700 at fs/btrfs/inode.c:956 cow_file_range.isra.19+0x32b/0x430 [btrfs]
  CPU: 1 PID: 23700 Comm: btrfs Kdump: loaded Tainted: G        W  O      4.20.0-rc4-custom+ #30
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
  RIP: 0010:cow_file_range.isra.19+0x32b/0x430 [btrfs]
  Call Trace:
   ? free_extent_buffer+0x46/0x90 [btrfs]
   run_delalloc_nocow+0x455/0x900 [btrfs]
   btrfs_run_delalloc_range+0x1a7/0x360 [btrfs]
   writepage_delalloc+0xf9/0x150 [btrfs]
   __extent_writepage+0x125/0x3e0 [btrfs]
   extent_write_cache_pages+0x1b6/0x3e0 [btrfs]
   ? __wake_up_common_lock+0x63/0xc0
   extent_writepages+0x50/0x80 [btrfs]
   do_writepages+0x41/0xd0
   ? __filemap_fdatawrite_range+0x9e/0xf0
   __filemap_fdatawrite_range+0xbe/0xf0
   btrfs_fdatawrite_range+0x1b/0x50 [btrfs]
   __btrfs_write_out_cache+0x42c/0x480 [btrfs]
   btrfs_write_out_ino_cache+0x84/0xd0 [btrfs]
   btrfs_save_ino_cache+0x551/0x660 [btrfs]
   commit_fs_roots+0xc5/0x190 [btrfs]
   btrfs_commit_transaction+0x2bf/0x8d0 [btrfs]
   btrfs_mksubvol+0x48d/0x4d0 [btrfs]
   btrfs_ioctl_snap_create_transid+0x170/0x180 [btrfs]
   btrfs_ioctl_snap_create_v2+0x124/0x180 [btrfs]
   btrfs_ioctl+0x123f/0x3030 [btrfs]

The file extent generation of the free space inode is equal to the last
snapshot of the file root, so the inode will be passed to cow_file_rage.
But the inode was created and its extents were preallocated in
btrfs_save_ino_cache, there are no cow copies on disk.

The preallocated extent is not yet in the extent tree, and
btrfs_cross_ref_exist will ignore the -ENOENT returned by
check_committed_ref, so we can directly write the inode to the disk.

Fixes: 78d4295b1e ("btrfs: lift some btrfs_cross_ref_exist checks in nocow path")
CC: stable@vger.kernel.org # 4.18+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:44 +01:00
Filipe Manana
41bd606769 Btrfs: fix fsync of files with multiple hard links in new directories
The log tree has a long standing problem that when a file is fsync'ed we
only check for new ancestors, created in the current transaction, by
following only the hard link for which the fsync was issued. We follow the
ancestors using the VFS' dget_parent() API. This means that if we create a
new link for a file in a directory that is new (or in an any other new
ancestor directory) and then fsync the file using an old hard link, we end
up not logging the new ancestor, and on log replay that new hard link and
ancestor do not exist. In some cases, involving renames, the file will not
exist at all.

Example:

  mkfs.btrfs -f /dev/sdb
  mount /dev/sdb /mnt

  mkdir /mnt/A
  touch /mnt/foo
  ln /mnt/foo /mnt/A/bar
  xfs_io -c fsync /mnt/foo

  <power failure>

In this example after log replay only the hard link named 'foo' exists
and directory A does not exist, which is unexpected. In other major linux
filesystems, such as ext4, xfs and f2fs for example, both hard links exist
and so does directory A after mounting again the filesystem.

Checking if any new ancestors are new and need to be logged was added in
2009 by commit 12fcfd22fe ("Btrfs: tree logging unlink/rename fixes"),
however only for the ancestors of the hard link (dentry) for which the
fsync was issued, instead of checking for all ancestors for all of the
inode's hard links.

So fix this by tracking the id of the last transaction where a hard link
was created for an inode and then on fsync fallback to a full transaction
commit when an inode has more than one hard link and at least one new hard
link was created in the current transaction. This is the simplest solution
since this is not a common use case (adding frequently hard links for
which there's an ancestor created in the current transaction and then
fsync the file). In case it ever becomes a common use case, a solution
that consists of iterating the fs/subvol btree for each hard link and
check if any ancestor is new, could be implemented.

This solves many unexpected scenarios reported by Jayashree Mohan and
Vijay Chidambaram, and for which there is a new test case for fstests
under review.

Fixes: 12fcfd22fe ("Btrfs: tree logging unlink/rename fixes")
CC: stable@vger.kernel.org # 4.4+
Reported-by: Vijay Chidambaram <vvijay03@gmail.com>
Reported-by: Jayashree Mohan <jayashree2912@gmail.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:43 +01:00
David Sterba
bbe339cc32 btrfs: drop extra enum initialization where using defaults
The first auto-assigned value to enum is 0, we can use that and not
initialize all members where the auto-increment does the same. This is
used for values that are not part of on-disk format.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:43 +01:00
David Sterba
5b840301ac btrfs: switch BTRFS_ORDERED_* to enums
We can use simple enum for values that are not part of on-disk format:
ordered extent flags.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:43 +01:00
David Sterba
50b5b6020f btrfs: switch EXTENT_FLAG_* to enums
We can use simple enum for values that are not part of on-disk format:
extent map flags.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:43 +01:00
David Sterba
80cb38362d btrfs: switch EXTENT_BUFFER_* to enums
We can use simple enum for values that are not part of on-disk format:
extent buffer flags;

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:43 +01:00
David Sterba
61fa90c16b btrfs: switch BTRFS_ROOT_* to enums
We can use simple enum for values that are not part of on-disk format:
root tree flags.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:42 +01:00
David Sterba
eb1a524c95 btrfs: switch BTRFS_FS_* to enums
We can use simple enum for values that are not part of on-disk format:
internal filesystem states.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:42 +01:00
David Sterba
688a75b9a3 btrfs: switch BTRFS_BLOCK_RSV_* to enums
We can use simple enum for values that are not part of on-disk format:
block reserve types.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:42 +01:00
David Sterba
b00146b5d5 btrfs: switch BTRFS_FS_STATE_* to enums
We can use simple enum for values that are not part of on-disk format:
global filesystem states.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:42 +01:00
Nikolay Borisov
da12fe5414 btrfs: Refactor btrfs_merge_bio_hook
This function really checks whether adding more data to the bio will
straddle a stripe/chunk. So first let's give it a more appropraite name
- btrfs_bio_fits_in_stripe. Secondly, the offset parameter was never
used to just remove it. Thirdly, pages are submitted to either btree or
data inodes so it's guaranteed that tree->ops is set so replace the
check with an ASSERT. Finally, document the parameters of the function.
No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:42 +01:00
Lu Fengqi
2ab4fd3135 btrfs: cleanup the useless DEFINE_WAIT in cleanup_transaction
When it was introduced in commit f094ac32ab ("Btrfs: fix NULL pointer
after aborting a transaction"), it was not used.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:42 +01:00
Johannes Thumshirn
d2e174d5d3 btrfs: document extent mapping assumptions in checksum
Document why map_private_extent_buffer() cannot return '1' (i.e. the map
spans two pages) for the csum_tree_block() case.

The current algorithm for detecting a page boundary crossing in
map_private_extent_buffer() will return a '1' *IFF* the extent buffer's
offset in the page + the offset passed in by csum_tree_block() and the
minimal length passed in by csum_tree_block() - 1 are bigger than
PAGE_SIZE.

We always pass BTRFS_CSUM_SIZE (32) as offset and a minimal length of 32
and the current extent buffer allocator always guarantees page aligned
extends, so the above condition can't be true.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:41 +01:00
Johannes Thumshirn
cc2c39d605 btrfs: don't initialize 'offset' in map_private_extent_buffer()
In map_private_extent_buffer() the 'offset' variable is initialized to a
page aligned version of the 'start' parameter.

But later on it is overwritten with either the offset from the extent
buffer's start or 0.

So get rid of the initial initialization.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:41 +01:00
Filipe Manana
a5fb114291 Btrfs: fix deadlock with memory reclaim during scrub
When a transaction commit starts, it attempts to pause scrub and it blocks
until the scrub is paused. So while the transaction is blocked waiting for
scrub to pause, we can not do memory allocation with GFP_KERNEL from scrub,
otherwise we risk getting into a deadlock with reclaim.

Checking for scrub pause requests is done early at the beginning of the
while loop of scrub_stripe() and later in the loop, scrub_extent() and
scrub_raid56_parity() are called, which in turn call scrub_pages() and
scrub_pages_for_parity() respectively. These last two functions do memory
allocations using GFP_KERNEL. Same problem could happen while scrubbing
the super blocks, since it calls scrub_pages().

We also can not have any of the worker tasks, created by the scrub task,
doing GFP_KERNEL allocations, because before pausing, the scrub task waits
for all the worker tasks to complete (also done at scrub_stripe()).

So make sure GFP_NOFS is used for the memory allocations because at any
time a scrub pause request can happen from another task that started to
commit a transaction.

Fixes: 58c4e17384 ("btrfs: scrub: use GFP_KERNEL on the submission path")
CC: stable@vger.kernel.org # 4.6+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:41 +01:00
Nikolay Borisov
78e62c02ab btrfs: Remove extent_io_ops::readpage_io_failed_hook
For data inodes this hook does nothing but to return -EAGAIN which is
used to signal to the endio routines that this bio belongs to a data
inode. If this is the case the actual retrying is handled by
bio_readpage_error. Alternatively, if this bio belongs to the btree
inode then btree_io_failed_hook just does some cleanup and doesn't retry
anything.

This patch simplifies the code flow by eliminating
readpage_io_failed_hook and instead open-coding btree_io_failed_hook in
end_bio_extent_readpage. Also eliminate some needless checks since IO is
always performed on either data inode or btree inode, both of which are
guaranteed to have their extent_io_tree::ops set.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:41 +01:00
Johannes Thumshirn
7b41ba71c1 btrfs: remove btrfs_bio_end_io_t
The btrfs_bio_end_io_t typedef was introduced with commit
a1d3c4786a ("btrfs: btrfs_multi_bio replaced with btrfs_bio")
but never used anywhere. This commit also introduced a forward declaration
of 'struct btrfs_bio' which is only needed for btrfs_bio_end_io_t.

Remove both as they're not needed anywhere.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:40 +01:00
David Sterba
b3a0dd50c3 btrfs: replace btrfs_io_bio::end_io with a simple helper
The end_io callback implemented as btrfs_io_bio_endio_readpage only
calls kfree. Also the callback is set only in case the csum buffer is
allocated and not pointing to the inline buffer. We can use that
information to drop the indirection and call a helper that will free the
csums only in the right case.

This shrinks struct btrfs_io_bio by 8 bytes.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:40 +01:00
David Sterba
31fecccbd7 btrfs: remove redundant csum buffer in btrfs_io_bio
The io_bio tracks checksums and has an inline buffer or an allocated
one. And there's a third member that points to the right one, but we
don't need to use an extra pointer for that. Let btrfs_io_bio::csum
point to the right buffer and check that the inline buffer is not
accidentally freed.

This shrinks struct btrfs_io_bio by 8 bytes.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:40 +01:00
David Sterba
600b6cf468 btrfs: replace async_cow::root with fs_info
The async_cow::root is used to propagate fs_info to async_cow_submit.
We can't use inode to reach it because it could become NULL after
write without compression in async_cow_start.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:40 +01:00
David Sterba
06ea01b1ee btrfs: merge btrfs_submit_bio_done to its caller
There's one caller and its code is simple, we can open code it in
run_one_async_done. The errors are passed through bio.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:40 +01:00
Anand Jain
7333bd02dc btrfs: balance: print to system log when balance ends or is paused
Print a kernel log message when the balance ends, either for cancel or
completed or if it is paused.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:39 +01:00
Anand Jain
56fc37d936 btrfs: balance: print args during start and resume
The information about balance arguments is important for system audit,
this patch prints the textual representation when balance starts or is
resumed.

Example command:

 $ btrfs balance start -f -mprofiles=raid1,convert=single,soft -dlimit=10..20,usage=50 /btrfs

Example kernel log output:

 BTRFS info (device sdb): balance: start -f -dusage=50,limit=10..20 -mconvert=single,soft,profiles=raid1 -sconvert=single,soft,profiles=raid1

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog, simplify code ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:39 +01:00
Anand Jain
f89e09cf45 btrfs: add helper to describe block group flags
Factor out helper that describes block group flags from
describe_relocation. The result will not be longer than the given size.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:39 +01:00
Filipe Manana
9a6f209e36 Btrfs: fix deadlock when enabling quotas due to concurrent snapshot creation
If the quota enable and snapshot creation ioctls are called concurrently
we can get into a deadlock where the task enabling quotas will deadlock
on the fs_info->qgroup_ioctl_lock mutex because it attempts to lock it
twice, or the task creating a snapshot tries to commit the transaction
while the task enabling quota waits for the former task to commit the
transaction while holding the mutex. The following time diagrams show how
both cases happen.

First scenario:

           CPU 0                                    CPU 1

 btrfs_ioctl()
  btrfs_ioctl_quota_ctl()
   btrfs_quota_enable()
    mutex_lock(fs_info->qgroup_ioctl_lock)
    btrfs_start_transaction()

                                             btrfs_ioctl()
                                              btrfs_ioctl_snap_create_v2
                                               create_snapshot()
                                                --> adds snapshot to the
                                                    list pending_snapshots
                                                    of the current
                                                    transaction

    btrfs_commit_transaction()
     create_pending_snapshots()
       create_pending_snapshot()
        qgroup_account_snapshot()
         btrfs_qgroup_inherit()
	   mutex_lock(fs_info->qgroup_ioctl_lock)
	    --> deadlock, mutex already locked
	        by this task at
		btrfs_quota_enable()

Second scenario:

           CPU 0                                    CPU 1

 btrfs_ioctl()
  btrfs_ioctl_quota_ctl()
   btrfs_quota_enable()
    mutex_lock(fs_info->qgroup_ioctl_lock)
    btrfs_start_transaction()

                                             btrfs_ioctl()
                                              btrfs_ioctl_snap_create_v2
                                               create_snapshot()
                                                --> adds snapshot to the
                                                    list pending_snapshots
                                                    of the current
                                                    transaction

                                                btrfs_commit_transaction()
                                                 --> waits for task at
                                                     CPU 0 to release
                                                     its transaction
                                                     handle

    btrfs_commit_transaction()
     --> sees another task started
         the transaction commit first
     --> releases its transaction
         handle
     --> waits for the transaction
         commit to be completed by
         the task at CPU 1

                                                 create_pending_snapshot()
                                                  qgroup_account_snapshot()
                                                   btrfs_qgroup_inherit()
                                                    mutex_lock(fs_info->qgroup_ioctl_lock)
                                                     --> deadlock, task at CPU 0
                                                         has the mutex locked but
                                                         it is waiting for us to
                                                         finish the transaction
                                                         commit

So fix this by setting the quota enabled flag in fs_info after committing
the transaction at btrfs_quota_enable(). This ends up serializing quota
enable and snapshot creation as if the snapshot creation happened just
before the quota enable request. The quota rescan task, scheduled after
committing the transaction in btrfs_quote_enable(), will do the accounting.

Fixes: 6426c7ad69 ("btrfs: qgroup: Fix qgroup accounting when creating snapshot")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:39 +01:00
Filipe Manana
5a8067c0d1 Btrfs: fix access to available allocation bits when starting balance
The available allocation bits members from struct btrfs_fs_info are
protected by a sequence lock, and when starting balance we access them
incorrectly in two different ways:

1) In the read sequence lock loop at btrfs_balance() we use the values we
   read from fs_info->avail_*_alloc_bits and we can immediately do actions
   that have side effects and can not be undone (printing a message and
   jumping to a label). This is wrong because a retry might be needed, so
   our actions must not have side effects and must be repeatable as long
   as read_seqretry() returns a non-zero value. In other words, we were
   essentially ignoring the sequence lock;

2) Right below the read sequence lock loop, we were reading the values
   from avail_metadata_alloc_bits and avail_data_alloc_bits without any
   protection from concurrent writers, that is, reading them outside of
   the read sequence lock critical section.

So fix this by making sure we only read the available allocation bits
while in a read sequence lock critical section and that what we do in the
critical section is repeatable (has nothing that can not be undone) so
that any eventual retry that is needed is handled properly.

Fixes: de98ced9e7 ("Btrfs: use seqlock to protect fs_info->avail_{data, metadata, system}_alloc_bits")
Fixes: 1450612797 ("btrfs: fix a bogus warning when converting only data or metadata")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:39 +01:00
Filipe Manana
0e6ec385b5 Btrfs: allow clear_extent_dirty() to receive a cached extent state record
We can have a lot freed extents during the life span of transaction, so
the red black tree that keeps track of the ranges of each freed extent
(fs_info->freed_extents[]) can get quite big. When finishing a
transaction commit we find each range, process it (discard the extents,
unpin them) and then remove it from the red black tree.

We can use an extent state record as a cache when searching for a range,
so that when we clean the range we can use the cached extent state we
passed to the search function instead of iterating the red black tree
again. Doing things as fast as possible when finishing a transaction (in
state TRANS_STATE_UNBLOCKED) is convenient as it reduces the time we
block another task that wants to commit the next transaction.

So change clear_extent_dirty() to allow an optional extent state record to
be passed as an argument, which will be passed down to __clear_extent_bit.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:38 +01:00
Nikolay Borisov
cc5de4e702 btrfs: Handle final split-brain possibility during fsid change
This patch lands the last case which needs to be handled by the fsid
change code. Namely, this is the case where a multidisk filesystem has
already undergone at least one successful fsid change i.e all disks
have the METADATA_UUID incompat bit and power failure occurs as another
fsid change is in progress. When such an event occurs, disks could be
split in 2 groups. One of the groups will have both METADATA_UUID and
CHANGING_FSID_V2 flags set coupled with old fsid/metadata_uuid pairs.
The other group of disks will have only METADATA_UUID bit set and their
fsid will be different than the one in disks in the first group. Here
we look at the following cases:

  a) A disk from the first group is scanned first, so fs_devices is
  created with stale fsid/metdata_uuid. Then when a disk from the
  second group is scanned it needs to first check whether there exists
  such an fs_devices that has fsid_change set to true (because it was
  created with a disk having the CHANGING_FSID_V2 flag), the
  metadata_uuid and fsid of the fs_devices will be different (since it was
  created by a disk which already has had at least 1 successful fsid change)
  and finally the metadata_uuid of the fs_devices will equal that of the
  currently scanned disk (because metadata_uuid never really changes).
  When the correct fs_devices is found the information from the scanned
  disk will replace the current one in fs_devices since the scanned disk
  will have higher generation number.

  b) A disk from the second group is scanned so fs_devices is created
  as usual with differing fsid/metdata_uid. Then when a disk from the
  first group is scanned the code detects that it has both
  CHANGING_FSID_V2 and METADATA_UUID flags set and will search for
  fs_devices that has differing metadata_uuid/fsid and whose
  metadata_uuid is the same as that of the scanned device.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:38 +01:00
Nikolay Borisov
7a62d0f073 btrfs: Handle one more split-brain scenario during fsid change
This commit continues hardening the scanning code to handle cases where
power loss could have caused disks in a multi-disk filesystem to be
in inconsistent state. Namely handle the situation that can occur when
some of the disks in multi-disk fs have completed their fsid change i.e
they have METADATA_UUID incompat flag set, have cleared the
CHANGING_FSID_V2 flag and their fsid/metadata_uuid are different. At
the same time the other half of the disks will have their
fsid/metadata_uuid unchanged and will only have CHANGING_FSID_V2 flag.

This is handled by introducing code in the scan path which:

 a) Handles the case when a device with CHANGING_FSID_V2 flag is
 scanned and as a result btrfs_fs_devices is created with matching
 fsid/metdata_uuid. Subsequently, when a device with completed fsid
 change is scanned it will detect this via the new code in find_fsid
 i.e that such an fs_devices exist that fsid_change flag is set to true,
 it's metadata_uuid/fsid match and the metadata_uuid of the scanned
 device matches that of the fs_devices. In this case, it's important to
 note that the devices which has its fsid change completed will have a
 higher generation number than the device with FSID_CHANGING_V2 flag
 set, so its superblock block will be used during mount. To prevent an
 assertion triggering because the sb used for mounting will have
 differing fsid/metadata_uuid than the ones in the fs_devices struct
 also add code in device_list_add which overwrites the values in
 fs_devices.

 b) Alternatively we can end up with a device that completed its
 fsid change be scanned first which will create the respective
 btrfs_fs_devices struct with differing fsid/metadata_uuid. In this
 case when a device with FSID_CHANGING_V2 flag set is scanned it will
 call the newly added find_fsid_inprogress function which will return
 the correct fs_devices.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:38 +01:00
Nikolay Borisov
d1a6300282 btrfs: add members to fs_devices to track fsid changes
In order to gracefully handle split-brain scenario during fsid change
(which are very unlikely, yet possible), two more pieces of information
will be necessary:

1. The highest generation number among all devices registered to a
   particular btrfs_fs_devices

2. A boolean flag whether a given btrfs_fs_devices was created by a
   device which had the FSID_CHANGING_V2 flag set.

This is a preparatory patch and just introduces the variables as well
as code which sets them, their actual use is going to happen in a later
patch.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:38 +01:00
Nikolay Borisov
fbc6feaec9 btrfs: Add handling for disk split-brain scenario during fsid change
Even though fsid change without rewrite is a very quick operation it's
still possible to experience a split-brain scenario if power loss occurs
at the most inconvenient time. This patch handles the case where power
failure occurs while the first transaction (the one setting
CHANGING_FSID_V2) flag is being persisted on disk. This can cause the
btrfs_fs_devices of this filesystem to be created by a device which:

 a) has the CHANGING_FSID_V2 flag set but its fsid value is intact

 b) or a device which doesn't have CHANGING_FSID_V2 flag set and its
    fsid value is intact

This situation is trivially handled by the current find_fsid code since
in both cases the devices are going to be treated like ordinary devices.
Since btrfs is always mounted using the superblock of the latest
device (the one with highest generation number), meaning it will have
the CHANGING_FSID_V2 flag set, ensure it's being cleared on mount. On
the first transaction commit following mount all disks will have it
cleared.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:38 +01:00
Nikolay Borisov
de37aa5131 btrfs: Remove fsid/metadata_fsid fields from btrfs_info
Currently btrfs_fs_info structure contains a copy of the
fsid/metadata_uuid fields. Same values are also contained in the
btrfs_fs_devices structure which fs_info has a reference to. Let's
reduce duplication by removing the fields from fs_info and always refer
to the ones in fs_devices. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:37 +01:00
Nikolay Borisov
56f20f4009 btrfs: Add sysfs support for metadata_uuid feature
Since the metadata_uuid is a new incompat feature it requires the
respective sysfs hooks. This patch adds the 'metdata_uuid' feature to
be shown if it supported by the kernel. Additionally it adds
/sys/fs/btrfs/UUID/metadata_uuid attribute which allows one to read
the current metadata_uuid.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:37 +01:00
Nikolay Borisov
7239ff4b2b btrfs: Introduce support for FSID change without metadata rewrite
This field is going to be used when the user wants to change the UUID
of the filesystem without having to rewrite all metadata blocks. This
field adds another level of indirection such that when the FSID is
changed what really happens is the current UUID (the one with which the
fs was created) is copied to the 'metadata_uuid' field in the superblock
as well as a new incompat flag is set METADATA_UUID. When the kernel
detects this flag is set it knows that the superblock in fact has 2
UUIDs:

1. Is the UUID which is user-visible, currently known as FSID.
2. Metadata UUID - this is the UUID which is stamped into all on-disk
   datastructures belonging to this file system.

When the new incompat flag is present device scanning checks whether
both fsid/metadata_uuid of the scanned device match any of the
registered filesystems. When the flag is not set then both UUIDs are
equal and only the FSID is retained on disk, metadata_uuid is set only
in-memory during mount.

Additionally a new metadata_uuid field is also added to the fs_info
struct. It's initialised either with the FSID in case METADATA_UUID
incompat flag is not set or with the metdata_uuid of the superblock
otherwise.

This commit introduces the new fields as well as the new incompat flag
and switches all users of the fsid to the new logic.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor updates in comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:37 +01:00
Johannes Thumshirn
ce9f967f31 btrfs: use EXPORT_FOR_TESTS for conditionally exported functions
Several functions in BTRFS are only used inside the source file they are
declared if CONFIG_BTRFS_FS_RUN_SANITY_TESTS is not defined. However if
CONFIG_BTRFS_FS_RUN_SANITY_TESTS is defined these functions are shared
with the unit tests code.

Before the introduction of the EXPORT_FOR_TESTS macro, these functions
could not be declared as static and the compiler had a harder task when
optimizing and inlining them.

As we have EXPORT_FOR_TESTS now, use it where appropriate to support the
compiler.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:37 +01:00
Johannes Thumshirn
f8f591df7d btrfs: introduce EXPORT_FOR_TESTS macro
Depending on whether CONFIG_BTRFS_FS_RUN_SANITY_TESTS is set, some BTRFS
functions are either local to the file they are implemented in and thus
should be declared static or are called from within the test
implementation defined in a different file.

Introduce an EXPORT_FOR_TESTS macro which depending on
CONFIG_BTRFS_FS_RUN_SANITY_TESTS either adds the 'static' keyword to a
function or not.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:37 +01:00
Johannes Thumshirn
e9a05cf31b btrfs: remove unused drop_on_err in btrfs_mkdir
Up to commit 32955c5422 ("btrfs: switch to discard_new_inode()") the
drop_on_err variable in btrfs_mkdir() was used to check whether the
inode had to be dropped via iput().

After commit 32955c5422 ("btrfs: switch to discard_new_inode()")
discard_new_inode() is called when err is set and inode is non NULL.
Therefore drop_on_err is not used anymore and thus causes a warning when
building with -Wunused-but-set-variable.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:36 +01:00
Nikolay Borisov
9bfd61d975 btrfs: Replace BUG_ON with ASSERT in find_lock_delalloc_range
lock_delalloc_pages should only return 2 values - 0 in case of success
and -EAGAIN if the range of pages to be locked should be shrunk due to
some of gone. Manual inspections confirms that this is indeed the case
since __process_pages_contig is where lock_delalloc_pages gets its
return value. The latter always returns 0  or -EAGAIN so the invariant
holds. No functional changes.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:36 +01:00
Nikolay Borisov
917aacecc5 btrfs: Sink find_lock_delalloc_range's 'max_bytes' argument
All callers of this function pass BTRFS_MAX_EXTENT_SIZE (128M) so let's
reduce the argument count and make that a local variable. No functional
changes.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:36 +01:00
Nikolay Borisov
64bc6c2a34 btrfs: Remove superfluous check form btrfs_remove_chunk
It's unnecessary to check map->stripes[i].dev for NULL given its value
is already set and dereferenced above the the check. No functional
changes.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:36 +01:00
Anand Jain
f9085abfae btrfs: don't report user-requested cancel as an error
As of now only user requested replace cancel can cancel the
replace-scrub so no need to log the error.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:36 +01:00
Anand Jain
49365e6976 btrfs: silence warning if replace is canceled
When we successfully cancel the device replace, its scrub worker returns
-ECANCELED, which is then passed to btrfs_dev_replace_finishing.

It cleans up based on the returned status and propagates the same
-ECANCELED back the parent function. As of now only user can cancel the
replace-scrub, so its ok to silence the warning here.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:35 +01:00
Anand Jain
53e62fb5a4 btrfs: dev-replace: add explicit check for replace result "no error"
We recast the replace return status
BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS to 0, to indicate no
error.
And since BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR should also return 0,
which is also declared as 0, so we just return. Instead add it to the if
statement so that there is enough clarity while reading the code.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:35 +01:00
Anand Jain
fe97e2e173 btrfs: dev-replace: replace's scrub must not be running in suspended state
When the replace state is in the suspended state, btrfs_scrub_cancel()
should fail with -ENOTCONN as there is no scrub running. As a safety
catch check if btrfs_scrub_cancel() returns -ENOTCONN and assert if it
doesn't.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:35 +01:00
Anand Jain
b47dda2ef6 btrfs: dev-replace: set result code of cancel by status of scrub
The device-replace needs to check the result code of the scrub workers
in btrfs_dev_replace_cancel and distinguish if successful cancel
operation and when the there was no operation running.

If btrfs_scrub_cancel() fails, return
BTRFS_IOCTL_DEV_REPLACE_RESULT_NOT_STARTED so that user can try
to cancel the replace again.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:35 +01:00
Anand Jain
d189dd70e2 btrfs: fix use-after-free due to race between replace start and cancel
The device replace cancel thread can race with the replace start thread
and if fs_info::scrubs_running is not yet set, btrfs_scrub_cancel() will
fail to stop the scrub thread.

The scrub thread continues with the scrub for replace which then will
try to write to the target device and which is already freed by the
cancel thread.

scrub_setup_ctx() warns as tgtdev is NULL.

  struct scrub_ctx *scrub_setup_ctx(struct btrfs_device *dev, int is_dev_replace)
  {
  ...
	  if (is_dev_replace) {
		  WARN_ON(!fs_info->dev_replace.tgtdev);  <===
		  sctx->pages_per_wr_bio = SCRUB_PAGES_PER_WR_BIO;
		  sctx->wr_tgtdev = fs_info->dev_replace.tgtdev;
		  sctx->flush_all_writes = false;
	  }

  [ 6724.497655] BTRFS info (device sdb): dev_replace from /dev/sdb (devid 1) to /dev/sdc started
  [ 6753.945017] BTRFS info (device sdb): dev_replace from /dev/sdb (devid 1) to /dev/sdc canceled
  [ 6852.426700] WARNING: CPU: 0 PID: 4494 at fs/btrfs/scrub.c:622 scrub_setup_ctx.isra.19+0x220/0x230 [btrfs]
  ...
  [ 6852.428928] RIP: 0010:scrub_setup_ctx.isra.19+0x220/0x230 [btrfs]
  ...
  [ 6852.432970] Call Trace:
  [ 6852.433202]  btrfs_scrub_dev+0x19b/0x5c0 [btrfs]
  [ 6852.433471]  btrfs_dev_replace_start+0x48c/0x6a0 [btrfs]
  [ 6852.433800]  btrfs_dev_replace_by_ioctl+0x3a/0x60 [btrfs]
  [ 6852.434097]  btrfs_ioctl+0x2476/0x2d20 [btrfs]
  [ 6852.434365]  ? do_sigaction+0x7d/0x1e0
  [ 6852.434623]  do_vfs_ioctl+0xa9/0x6c0
  [ 6852.434865]  ? syscall_trace_enter+0x1c8/0x310
  [ 6852.435124]  ? syscall_trace_enter+0x1c8/0x310
  [ 6852.435387]  ksys_ioctl+0x60/0x90
  [ 6852.435663]  __x64_sys_ioctl+0x16/0x20
  [ 6852.435907]  do_syscall_64+0x50/0x180
  [ 6852.436150]  entry_SYSCALL_64_after_hwframe+0x49/0xbe

Further, as the replace thread enters scrub_write_page_to_dev_replace()
without the target device it panics:

  static int scrub_add_page_to_wr_bio(struct scrub_ctx *sctx,
				      struct scrub_page *spage)
  {
  ...
	bio_set_dev(bio, sbio->dev->bdev); <======

  [ 6929.715145] BUG: unable to handle kernel NULL pointer dereference at 00000000000000a0
  ..
  [ 6929.717106] Workqueue: btrfs-scrub btrfs_scrub_helper [btrfs]
  [ 6929.717420] RIP: 0010:scrub_write_page_to_dev_replace+0xb4/0x260
  [btrfs]
  ..
  [ 6929.721430] Call Trace:
  [ 6929.721663]  scrub_write_block_to_dev_replace+0x3f/0x60 [btrfs]
  [ 6929.721975]  scrub_bio_end_io_worker+0x1af/0x490 [btrfs]
  [ 6929.722277]  normal_work_helper+0xf0/0x4c0 [btrfs]
  [ 6929.722552]  process_one_work+0x1f4/0x520
  [ 6929.722805]  ? process_one_work+0x16e/0x520
  [ 6929.723063]  worker_thread+0x46/0x3d0
  [ 6929.723313]  kthread+0xf8/0x130
  [ 6929.723544]  ? process_one_work+0x520/0x520
  [ 6929.723800]  ? kthread_delayed_work_timer_fn+0x80/0x80
  [ 6929.724081]  ret_from_fork+0x3a/0x50

Fix this by letting the btrfs_dev_replace_finishing() to do the job of
cleaning after the cancel, including freeing of the target device.
btrfs_dev_replace_finishing() is called when btrfs_scub_dev() returns
along with the scrub return status.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:35 +01:00
Anand Jain
05c49e6bc1 btrfs: dev-replace: go back to suspend state if another EXCL_OP is running
In a secnario where balance and replace co-exists as below,

  - start balance
  - pause balance
  - start replace
  - reboot

and when system restarts, balance resumes first. Then the replace is
attempted to restart but will fail as the EXCL_OP lock is already held
by the balance. If so place the replace state back to
BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED state.

Fixes: 010a47bde9 ("btrfs: add proper safety check before resuming dev-replace")
CC: stable@vger.kernel.org # 4.18+
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:34 +01:00
Anand Jain
0d228ece59 btrfs: dev-replace: go back to suspended state if target device is missing
At the time of forced unmount we place the running replace to
BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED state, so when the system comes
back and expect the target device is missing.

Then let the replace state continue to be in
BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED state instead of
BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED as there isn't any matching scrub
running as part of replace.

Fixes: e93c89c1aa ("Btrfs: add new sources for device replace code")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:34 +01:00
Anand Jain
54862d6d28 btrfs: mark btrfs_dev_replace_start as static
There isn't any other consumer other than in its own file dev-replace.c.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:34 +01:00
Anand Jain
a9261d4125 btrfs: harden agaist duplicate fsid on scanned devices
It's not that impossible to imagine that a device OR a btrfs image is
copied just by using the dd or the cp command. Which in case both the
copies of the btrfs will have the same fsid. If on the system with
automount enabled, the copied FS gets scanned.

We have a known bug in btrfs, that we let the device path be changed
after the device has been mounted. So using this loop hole the new
copied device would appears as if its mounted immediately after it's
been copied.

For example:

Initially.. /dev/mmcblk0p4 is mounted as /

  $ lsblk
  NAME        MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
  mmcblk0     179:0    0 29.2G  0 disk
  |-mmcblk0p4 179:4    0    4G  0 part /
  |-mmcblk0p2 179:2    0  500M  0 part /boot
  |-mmcblk0p3 179:3    0  256M  0 part [SWAP]
  `-mmcblk0p1 179:1    0  256M  0 part /boot/efi

  $ btrfs fi show
     Label: none  uuid: 07892354-ddaa-4443-90ea-f76a06accaba
     Total devices 1 FS bytes used 1.40GiB
     devid    1 size 4.00GiB used 3.00GiB path /dev/mmcblk0p4

Copy mmcblk0 to sda

  $ dd if=/dev/mmcblk0 of=/dev/sda

And immediately after the copy completes the change in the device
superblock is notified which the automount scans using btrfs device scan
and the new device sda becomes the mounted root device.

  $ lsblk
  NAME        MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
  sda           8:0    1 14.9G  0 disk
  |-sda4        8:4    1    4G  0 part /
  |-sda2        8:2    1  500M  0 part
  |-sda3        8:3    1  256M  0 part
  `-sda1        8:1    1  256M  0 part
  mmcblk0     179:0    0 29.2G  0 disk
  |-mmcblk0p4 179:4    0    4G  0 part
  |-mmcblk0p2 179:2    0  500M  0 part /boot
  |-mmcblk0p3 179:3    0  256M  0 part [SWAP]
  `-mmcblk0p1 179:1    0  256M  0 part /boot/efi

  $ btrfs fi show /
    Label: none  uuid: 07892354-ddaa-4443-90ea-f76a06accaba
    Total devices 1 FS bytes used 1.40GiB
    devid    1 size 4.00GiB used 3.00GiB path /dev/sda4

The bug is quite nasty that you can't either unmount /dev/sda4 or
/dev/mmcblk0p4. And the problem does not get solved until you take sda
out of the system on to another system to change its fsid using the
'btrfstune -u' command.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:34 +01:00
Hans van Kranenburg
b50836edf9 btrfs: introduce nparity raid_attr
Instead of hardcoding exceptions for RAID5 and RAID6 in the code, use an
nparity field in raid_attr.

Signed-off-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:34 +01:00
Hans van Kranenburg
da612e31ae btrfs: fix ncopies raid_attr for RAID56
RAID5 and RAID6 profile store one copy of the data, not 2 or 3. These
values are not yet used anywhere so there's no change.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:33 +01:00
Hans van Kranenburg
baf92114c7 btrfs: alloc_chunk: fix more DUP stripe size handling
Commit 92e222df7b "btrfs: alloc_chunk: fix DUP stripe size handling"
fixed calculating the stripe_size for a new DUP chunk.

However, the same calculation reappears a bit later, and that one was
not changed yet. The resulting bug that is exposed is that the newly
allocated device extents ('stripes') can have a few MiB overlap with the
next thing stored after them, which is another device extent or the end
of the disk.

The scenario in which this can happen is:
* The block device for the filesystem is less than 10GiB in size.
* The amount of contiguous free unallocated disk space chosen to use for
  chunk allocation is 20% of the total device size, or a few MiB more or
  less.

An example:
- The filesystem device is 7880MiB (max_chunk_size gets set to 788MiB)
- There's 1578MiB unallocated raw disk space left in one contiguous
  piece.

In this case stripe_size is first calculated as 789MiB, (half of
1578MiB).

Since 789MiB (stripe_size * data_stripes) > 788MiB (max_chunk_size), we
enter the if block. Now stripe_size value is immediately overwritten
while calculating an adjusted value based on max_chunk_size, which ends
up as 788MiB.

Next, the value is rounded up to a 16MiB boundary, 800MiB, which is
actually more than the value we had before. However, the last comparison
fails to detect this, because it's comparing the value with the total
amount of free space, which is about twice the size of stripe_size.

In the example above, this means that the resulting raw disk space being
allocated is 1600MiB, while only a gap of 1578MiB has been found. The
second device extent object for this DUP chunk will overlap for 22MiB
with whatever comes next.

The underlying problem here is that the stripe_size is reused all the
time for different things. So, when entering the code in the if block,
stripe_size is immediately overwritten with something else. If later we
decide we want to have the previous value back, then the logic to
compute it was copy pasted in again.

With this change, the value in stripe_size is not unnecessarily
destroyed, so the duplicated calculation is not needed any more.

Signed-off-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:33 +01:00
Hans van Kranenburg
23f0ff1ec4 btrfs: alloc_chunk: improve chunk size variable name
The variable num_bytes is really a way too generic name for a variable
in this function. There are a dozen other variables that hold a number
of bytes as value.

Give it a name that actually describes what it does, which is holding
the size of the chunk that we're allocating.

Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:33 +01:00
Hans van Kranenburg
2f29df4fc2 btrfs: alloc_chunk: do not refurbish num_bytes
The variable num_bytes is used to store the chunk length of the chunk
that we're allocating. Do not reuse it for something really different in
the same function.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:33 +01:00
Ethan Lien
3cd24c6980 btrfs: use tagged writepage to mitigate livelock of snapshot
Snapshot is expected to be fast. But if there are writers steadily
creating dirty pages in our subvolume, the snapshot may take a very long
time to complete. To fix the problem, we use tagged writepage for
snapshot flusher as we do in the generic write_cache_pages(), so we can
omit pages dirtied after the snapshot command.

This does not change the semantics regarding which data get to the
snapshot, if there are pages being dirtied during the snapshotting
operation.  There's a sync called before snapshot is taken in old/new
case, any IO in flight just after that may be in the snapshot but this
depends on other system effects that might still sync the IO.

We do a simple snapshot speed test on a Intel D-1531 box:

fio --ioengine=libaio --iodepth=32 --bs=4k --rw=write --size=64G
--direct=0 --thread=1 --numjobs=1 --time_based --runtime=120
--filename=/mnt/sub/testfile --name=job1 --group_reporting & sleep 5;
time btrfs sub snap -r /mnt/sub /mnt/snap; killall fio

original: 1m58sec
patched:  6.54sec

This is the best case for this patch since for a sequential write case,
we omit nearly all pages dirtied after the snapshot command.

For a multi writers, random write test:

fio --ioengine=libaio --iodepth=32 --bs=4k --rw=randwrite --size=64G
--direct=0 --thread=1 --numjobs=4 --time_based --runtime=120
--filename=/mnt/sub/testfile --name=job1 --group_reporting & sleep 5;
time btrfs sub snap -r /mnt/sub /mnt/snap; killall fio

original: 15.83sec
patched:  10.35sec

The improvement is smaller compared to the sequential write case,
since we omit only half of the pages dirtied after snapshot command.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Ethan Lien <ethanlien@synology.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:33 +01:00
Nikolay Borisov
c629732d24 btrfs: Remove unused extent_state argument from btrfs_writepage_endio_finish_ordered
This parameter was never used, yet was part of the interface of the
function ever since its introduction as extent_io_ops::writepage_end_io_hook
in e6dcd2dc9c ("Btrfs: New data=ordered implementation"). Now that
NULL is passed everywhere as a value for this parameter let's remove it
for good. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:32 +01:00
Nikolay Borisov
8cc0237abc btrfs: Remove extent_page_data argument from writepage_delalloc
The only remaining use of the 'epd' argument in writepage_delalloc is
to reference the extent_io_tree which was set in extent_writepages. Since
it is guaranteed that page->mapping of any page passed to
writepage_delalloc (and __extent_writepage as the sole caller) to be
equal to that passed in extent_writepages we can directly get the
io_tree via the already passed inode (which is also taken from
page->mapping->host). No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:32 +01:00
Nikolay Borisov
7789a55aa1 btrfs: Move epd::extent_locked check to writepage_delalloc's caller
If epd::extent_locked is set then writepage_delalloc terminates. Make
this a bit more apparent in the caller by simply bubbling the check up.
This enables to remove epd as an argument to writepage_delalloc in a
future patch. No functional change.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:32 +01:00
Nikolay Borisov
fc8a168aa9 btrfs: Check for missing device before bio submission in btrfs_map_bio
Before btrfs_map_bio submits all stripe bios it does a number of checks
to ensure the device for every stripe is present. However, it doesn't do
a DEV_STATE_MISSING check, instead this is relegated to the lower level
btrfs_schedule_bio (in the async submission case, sync submission
doesn't check DEV_STATE_MISSING at all). Additionally
btrfs_schedule_bios does the duplicate device->bdev check which has
already been performed in btrfs_map_bio.

This patch moves the DEV_STATE_MISSING check in btrfs_map_bio and
removes the duplicate device->bdev check. Doing so ensures that no bio
cloning/submission happens for both async/sync requests in the face of
missing device. This makes the async io submission path slightly shorter
in terms of instruction count. No functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:32 +01:00
Anand Jain
ab457246f8 btrfs: remove redundant replace_state init
dev_replace::replace_state has been set to
BTRFS_DEV_REPLACE_ITEM_STATE_NEVER_STARTED (0) in the same function,
So delete the line which sets replace_state = 0;

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:32 +01:00
Filipe Manana
6d4cbf7903 Btrfs: remove no longer used io_err from btrfs_log_ctx
The io_err field of struct btrfs_log_ctx is no longer used after the
recent simplification of the fast fsync path, where we now wait for
ordered extents to complete before logging the inode. We did this in
commit b5e6c3e170 ("btrfs: always wait on ordered extents at fsync
time") and commit a2120a473a ("btrfs: clean up the left over
logged_list usage") removed its last use.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:31 +01:00
Filipe Manana
59b0713a8a Btrfs: simpler and more efficient cleanup of a log tree's extent io tree
We currently are in a loop finding each range (corresponding to a btree
node/leaf) in a log root's extent io tree and then clean it up. This is a
waste of time since we are traversing the extent io tree's rb_tree more
times then needed (one for a range lookup and another for cleaning it up)
without any good reason.

We free the log trees when we are in the critical section of a transaction
commit (the transaction state is set to TRANS_STATE_COMMIT_DOING), so it's
of great convenience to do everything as fast as possible in order to
reduce the time we block other tasks from starting a new transaction.

So fix this by traversing the extent io tree once and cleaning up all its
records in one go while traversing it.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:31 +01:00
Nikolay Borisov
46cc775e29 btrfs: Adjust loop in free_extent_buffer
The loop construct in free_extent_buffer was added in
242e18c7c1 ("Btrfs: reduce lock contention on extent buffer locks")
as means of reducing the times the eb lock is taken, the non-last ref
count is decremented and lock is released. As the special handling
of UNMAPPED extent buffers was removed now there is only one decrement
op which is happening for EXTENT_BUFFER_UNMAPPED case.

This commit modifies the loop condition so that in case of UNMAPPED
buffers the eb's lock is taken only if we are 100% sure the eb is going
to be freed by the current executor of the code. Additionally, remove
superfluous ref count ops in btrfs test.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:31 +01:00
Nikolay Borisov
9cfc8ba712 btrfs: Remove special handling of EXTENT_BUFFER_UNMAPPED while freeing
Now that the whole of btrfs code has been audited for eb reference count
management it's time to remove the hunk in free_extent_buffer that
essentially considered the condition

  "eb->ref == 2 && EXTENT_BUFFER_DUMMY"

to equal "eb->ref = 1". Also remove the last location
which takes an extra reference count in alloc_test_extent_buffer.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:31 +01:00
Nikolay Borisov
df44971468 btrfs: Remove unnecessary tree locking code in qgroup_rescan_leaf
In qgroup_rescan_leaf a copy is made of the target leaf by calling
btrfs_clone_extent_buffer. The latter allocates a new buffer and
attaches a new set of pages and copies the content of the source buffer.
The new scratch buffer is only used to iterate it's items, it's not
published anywhere and cannot be accessed by a third party.

Hence, it's not necessary to perform any locking on it whatsoever.
Furthermore, remove the extra extent_buffer_get call since the new
buffer is always allocated with a reference count of 1 which is
sufficient here.  No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:31 +01:00
Nikolay Borisov
8c7eeb6557 btrfs: Remove extra reference count bumps in btrfs_compare_trees
When the 2 comparison trees roots are initialised they are private to
the function and already have reference counts of 1 each. There is no
need to further increment the reference count since the cloned buffers
are already accessed via struct btrfs_path. Eventually the 2 paths used
for comparison are going to be released, effectively disposing of the
cloned buffers.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:30 +01:00
Nikolay Borisov
24cee18a1c btrfs: Remove extraneous extent_buffer_get from tree_mod_log_rewind
When a rewound buffer is created it already has a ref count of 1 and the
dummy flag set. Then another ref is taken bumping the count to 2.
Finally when this buffer is released from btrfs_release_path the extra
reference is decremented by the special handling code in
free_extent_buffer.

However, this special code is in fact redundant sinca ref count of 1 is
still correct since the buffer is only accessed via btrfs_path struct.
This paves the way forward of removing the special handling in
free_extent_buffer.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:30 +01:00
Nikolay Borisov
6c122e2a0c btrfs: Remove redundant extent_buffer_get in get_old_root
get_old_root used used only by btrfs_search_old_slot to initialise the
path structure. The old root is always a cloned buffer (either via alloc
dummy or via btrfs_clone_extent_buffer) and its reference count is 2: 1
from allocation, 1 from extent_buffer_get call in get_old_root.

This latter explicit ref count acquire operation is in fact unnecessary
since the semantic is such that the newly allocated buffer is handed
over to the btrfs_path for lifetime management. Considering this just
remove the extra extent_buffer_get in get_old_root.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:30 +01:00
Nikolay Borisov
5c623d334a btrfs: Remove needless tree locking in iterate_inode_extrefs
In iterate_inode_exrefs the eb is cloned via btrfs_clone_extent_buffer
which creates a private extent buffer with the dummy flag set and ref
count of 1. Then this buffer is locked for reading and its ref count is
incremented by 1. Finally it's fed to the passed iterate_irefs_t
function. The actual iterate call back is inode_to_path (coming from
paths_from_inode) which feeds the eb to btrfs_ref_to_path. In this final
function the passed eb is only read by first assigning it to the local
eb variable. This variable is only modified in the case another eb was
referenced from the passed path that is eb != eb_in check triggers.

Considering this there is no point in locking the cloned eb in
iterate_inode_refs since it's never being modified and is not published
anywhere. Furthermore the cloned eb is completely fine having its ref
count be 1.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:30 +01:00
Nikolay Borisov
e5bba0b0f8 btrfs: Remove needless tree locking in iterate_inode_refs
In iterate_inode_refs the eb is cloned via btrfs_clone_extent_buffer
which creates a private extent buffer with the dummy flag set and ref
count of 1. Then this buffer is locked for reading and its ref count is
incremented by 1. Finally it's fed to the passed iterate_irefs_t
function. The actual iterate call back is inode_to_path (coming from
paths_from_inode) which feeds the eb to btrfs_ref_to_path. In this final
function the passed eb is only read by first assigning it to the local
eb variable. This variable is only modified in the case another eb was
referenced from the passed path that is eb != eb_in check triggers.

Considering this there is no point in locking the cloned eb in
iterate_inode_refs since it's never being modified and is not published
anywhere. Furthermore the cloned eb is completely fine having its ref
count be 1.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:30 +01:00
Qu Wenruo
d9cb2459b2 btrfs: tests: Use BTRFS_MAX_EXTENT_SIZE to replace the intermediate number
In extent-io self test, we need 2 ordered extents at its maximum size to
do the test.

Instead of using the intermediate numbers, use BTRFS_MAX_EXTENT_SIZE for
@max_bytes, and twice @max_bytes for @total_dirty.  This should explain
why we need all these magic numbers and prevent people to modify them by
accident.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:30 +01:00
Omar Sandoval
ed46ff3d42 Btrfs: support swap files
Btrfs has not allowed swap files since commit 35054394c4 ("Btrfs: stop
providing a bmap operation to avoid swapfile corruptions"). However, now
that the proper restrictions are in place, Btrfs can support swap files
through the swap file a_ops, similar to iomap in commit 67482129cd
("iomap: add a swapfile activation function").

For Btrfs, activation needs to make sure that the file can be used as a
swap file, which currently means that it must be fully allocated as
NOCOW with no compression on one device. It must also do the proper
tracking so that ioctls will not interfere with the swap file.
Deactivation clears this tracking.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:29 +01:00
Omar Sandoval
60ca842e34 Btrfs: rename and export get_chunk_map
The Btrfs swap code is going to need it, so give it a btrfs_ prefix and
make it non-static.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:29 +01:00
Omar Sandoval
eede2bf34f Btrfs: prevent ioctls from interfering with a swap file
A later patch will implement swap file support for Btrfs, but before we
do that, we need to make sure that the various Btrfs ioctls cannot
change a swap file.

When a swap file is active, we must make sure that the extents of the
file are not moved and that they don't become shared. That means that
the following are not safe:

- chattr +c (enable compression)
- reflink
- dedupe
- snapshot
- defrag

Don't allow those to happen on an active swap file.

Additionally, balance, resize, device remove, and device replace are
also unsafe if they affect an active swapfile. Add a red-black tree of
block groups and devices which contain an active swapfile. Relocation
checks each block group against this tree and skips it or errors out for
balance or resize, respectively. Device remove and device replace check
the tree for the device they will operate on.

Note that we don't have to worry about chattr -C (disable nocow), which
we ignore for non-empty files, because an active swapfile must be
non-empty and can't be truncated. We also don't have to worry about
autodefrag because it's only done on COW files. Truncate and fallocate
are already taken care of by the generic code. Device add doesn't do
relocation so it's not an issue, either.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:29 +01:00
Nikolay Borisov
abbb55f4cd btrfs: Remove extent_io_ops::split_extent_hook callback
This is the counterpart to merge_extent_hook, similarly, it's used only
for data/freespace inodes so let's remove it, rename it and call it
directly where necessary. No functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:29 +01:00
Nikolay Borisov
5c848198aa btrfs: Remove extent_io_ops::merge_extent_hook callback
This callback is used only for data and free space inodes. Such inodes
are guaranteed to have their extent_io_tree::private_data set to the
inode struct. Exploit this fact to directly call the function. Also give
it a more descriptive name. No functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:28 +01:00
Nikolay Borisov
a36bb5f9a9 btrfs: Remove extent_io_ops::clear_bit_hook callback
This is the counterpart to ex-set_bit_hook (now btrfs_set_delalloc_extent),
similar to what was done before remove clear_bit_hook and rename the
function. No functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:28 +01:00
Nikolay Borisov
e06a1fc99c btrfs: Remove extent_io_ops::set_bit_hook extent_io callback
This callback is used to properly account delalloc extents for data
inodes (ordinary file inodes and freespace v1 inodes). Those can be
easily identified since they have their extent_io trees ->private_data
member point to the inode. Let's exploit this fact to remove the
needless indirection through extent_io_hooks and directly call the
function. Also give the function a name which reflects its purpose -
btrfs_set_delalloc_extent.

This patch also modified test_find_delalloc so that the extent_io_tree
used for testing doesn't have its ->private_data set which would have
caused a crash in btrfs_set_delalloc_extent due to the btrfs_inode->root
member not being initialised. The old version of the code also didn't
call set_bit_hook since the extent_io ops weren't set for the inode.  No
functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:28 +01:00
Nikolay Borisov
65a680f6b7 btrfs: Remove extent_io_ops::check_extent_io_range callback
This callback was only used in debug builds by btrfs_leak_debug_check.
A better approach is to move its implementation in
btrfs_leak_debug_check and ensure the latter is only executed for extent
tree which have ->private_data set i.e. relate to a data node and not
the btree one. No functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:28 +01:00
Nikolay Borisov
7087a9d8db btrfs: Remove extent_io_ops::writepage_end_io_hook
This callback is ony ever called for data page writeout so there is no
need to actually abstract it via extent_io_ops. Lets just export it,
remove the definition of the callback and call it directly in the
functions that invoke the callback. Also rename the function to
btrfs_writepage_endio_finish_ordered since what it really does is
account finished io in the ordered extent data structures.  No
functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:28 +01:00
Nikolay Borisov
d75855b451 btrfs: Remove extent_io_ops::writepage_start_hook
This hook is called only from __extent_writepage_io which is already
called only from the data page writeout path. So there is no need to
make an indirect call via extent_io_ops. This patch just removes the
callback definition, exports the callback function and calls it directly
at the only call site. Also give the function a more descriptive name.
No functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:27 +01:00
Nikolay Borisov
5eaad97af8 btrfs: Remove extent_io_ops::fill_delalloc
This callback is called only from writepage_delalloc which in turn is
guaranteed to be called from the data page writeout path. In the end
there is no reason to have the call to this function to be indrected via
the extent_io_ops structure. This patch removes the callback definition,
exports the function and calls it directly. No functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ rename to btrfs_run_delalloc_range ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:27 +01:00
Nikolay Borisov
06f2548f9d btrfs: Add function to distinguish between data and btree inode
This will be used in future patches that remove the optional
extent_io_ops callbacks.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:27 +01:00
Qu Wenruo
05a37c4860 btrfs: volumes: Make sure no dev extent is beyond device boundary
Add extra dev extent end check against device boundary.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:27 +01:00
Qu Wenruo
5eb193812a btrfs: volumes: Make sure there is no overlap of dev extents at mount time
Enhance btrfs_verify_dev_extents() to remember previous checked dev
extents, so it can verify no dev extents can overlap.

Analysis from Hans:

"Imagine allocating a DATA|DUP chunk.

 In the chunk allocator, we first set...
   max_stripe_size = SZ_1G;
   max_chunk_size = BTRFS_MAX_DATA_CHUNK_SIZE
 ... which is 10GiB.

 Then...
   /* we don't want a chunk larger than 10% of writeable space */
   max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
       		 max_chunk_size);

 Imagine we only have one 7880MiB block device in this filesystem. Now
 max_chunk_size is down to 788MiB.

 The next step in the code is to search for max_stripe_size * dev_stripes
 amount of free space on the device, which is in our example 1GiB * 2 =
 2GiB. Imagine the device has exactly 1578MiB free in one contiguous
 piece. This amount of bytes will be put in devices_info[ndevs - 1].max_avail

 Next we recalculate the stripe_size (which is actually the device extent
 length), based on the actual maximum amount of available raw disk space:
   stripe_size = div_u64(devices_info[ndevs - 1].max_avail, dev_stripes);

 stripe_size is now 789MiB

 Next we do...
   data_stripes = num_stripes / ncopies
 ...where data_stripes ends up as 1, because num_stripes is 2 (the amount
 of device extents we're going to have), and DUP has ncopies 2.

 Next there's a check...
   if (stripe_size * data_stripes > max_chunk_size)
 ...which matches because 789MiB * 1 > 788MiB.

 We go into the if code, and next is...
   stripe_size = div_u64(max_chunk_size, data_stripes);
 ...which resets stripe_size to max_chunk_size: 788MiB

 Next is a fun one...
   /* bump the answer up to a 16MB boundary */
   stripe_size = round_up(stripe_size, SZ_16M);
 ...which changes stripe_size from 788MiB to 800MiB.

 We're not done changing stripe_size yet...
   /* But don't go higher than the limits we found while searching
    * for free extents
    */
   stripe_size = min(devices_info[ndevs - 1].max_avail,
       	      stripe_size);

 This is bad. max_avail is twice the stripe_size (we need to fit 2 device
 extents on the same device for DUP).

 The result here is that 800MiB < 1578MiB, so it's unchanged. However,
 the resulting DUP chunk will need 1600MiB disk space, which isn't there,
 and the second dev_extent might extend into the next thing (next
 dev_extent? end of device?) for 22MiB.

 The last shown line of code relies on a situation where there's twice
 the value of stripe_size present as value for the variable stripe_size
 when it's DUP. This was actually the case before commit 92e222df7b
 "btrfs: alloc_chunk: fix DUP stripe size handling", from which I quote:
   "[...] in the meantime there's a check to see if the stripe_size does
 not exceed max_chunk_size. Since during this check stripe_size is twice
 the amount as intended, the check will reduce the stripe_size to
 max_chunk_size if the actual correct to be used stripe_size is more than
 half the amount of max_chunk_size."

 In the previous version of the code, the 16MiB alignment (why is this
 done, by the way?) would result in a 50% chance that it would actually
 do an 8MiB alignment for the individual dev_extents, since it was
 operating on double the size. Does this matter?

 Does it matter that stripe_size can be set to anything which is not
 16MiB aligned because of the amount of remaining available disk space
 which is just taken?

 What is the main purpose of this round_up?

 The most straightforward thing to do seems something like...
   stripe_size = min(
       div_u64(devices_info[ndevs - 1].max_avail, dev_stripes),
       stripe_size
   )
 ..just putting half of the max_avail into stripe_size."

Link: https://lore.kernel.org/linux-btrfs/b3461a38-e5f8-f41d-c67c-2efac8129054@mendix.com/
Reported-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
[ add analysis from report ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:27 +01:00
Qu Wenruo
e72d79d6bc btrfs: Refactor find_free_extent loops update into find_free_extent_update_loop
We have a complex loop design for find_free_extent(), that has different
behavior for each loop, some even includes new chunk allocation.

Instead of putting such a long code into find_free_extent() and makes it
harder to read, just extract them into find_free_extent_update_loop().

With all the cleanups, the main find_free_extent() should be pretty
barebone:

find_free_extent()
|- Iterate through all block groups
|  |- Get a valid block group
|  |- Try to do clustered allocation in that block group
|  |- Try to do unclustered allocation in that block group
|  |- Check if the result is valid
|  |  |- If valid, then exit
|  |- Jump to next block group
|
|- Push harder to find free extents
   |- If not found, re-iterate all block groups

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
[ copy callchain from changelog to function comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:26 +01:00
Qu Wenruo
e1a4184815 btrfs: Refactor unclustered extent allocation into find_free_extent_unclustered()
This patch will extract unclsutered extent allocation code into
find_free_extent_unclustered().

And this helper function will use return value to indicate what to do
next.

This should make find_free_extent() a little easier to read.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
[Update merge conflict with fb5c39d7a8 ("btrfs: don't use ctl->free_space for max_extent_size")]
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:26 +01:00
Qu Wenruo
d06e3bb690 btrfs: Refactor clustered extent allocation into find_free_extent_clustered
We have two main methods to find free extents inside a block group:

1) clustered allocation
2) unclustered allocation

This patch will extract the clustered allocation into
find_free_extent_clustered() to make it a little easier to read.

Instead of jumping between different labels in find_free_extent(), the
helper function will use return value to indicate different behavior.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:26 +01:00
Qu Wenruo
b4bd745d12 btrfs: Introduce find_free_extent_ctl structure for later rework
Instead of tons of different local variables in find_free_extent(),
extract them into find_free_extent_ctl structure, and add better
explanation for them.

Some modification may looks redundant, but will later greatly simplify
function parameter list during find_free_extent() refactor.

Also add two comments to co-operate with fb5c39d7a8 ("btrfs: don't use
ctl->free_space for max_extent_size"), to make ffe_ctl->max_extent_size
update more reader-friendly.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:26 +01:00
Lu Fengqi
e2907c1a6a btrfs: extent-tree: Detect bytes_pinned underflow earlier
Introduce a new wrapper update_bytes_pinned to replace open coded
bytes_pinned modifiers. Now the underflows of space_info::bytes_pinned
get detected and reported.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:26 +01:00
Qu Wenruo
9f9b8e8d0e btrfs: extent-tree: Detect bytes_may_use underflow earlier
Although we have space_info::bytes_may_use underflow detection in
btrfs_free_reserved_data_space_noquota(), we have more callers who are
subtracting number from space_info::bytes_may_use.

So instead of doing underflow detection for every caller, introduce a
new wrapper update_bytes_may_use() to replace open coded bytes_may_use
modifiers.

This also introduce a macro to declare more wrappers, but currently
space_info::bytes_may_use is the mostly interesting one.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:25 +01:00
Filipe Manana
85dd506c8e Btrfs: remove no longer used stuff for tracking pending ordered extents
Tracking pending ordered extents per transaction was introduced in commit
50d9aa99bd ("Btrfs: make sure logged extents complete in the current
transaction V3") and later updated in commit 161c3549b4 ("Btrfs: change
how we wait for pending ordered extents").

However now that on fsync we always wait for ordered extents to complete
before logging, done in commit 5636cf7d6d ("btrfs: remove the logged
extents infrastructure"), we no longer need the stuff to track for pending
ordered extents, which was not completely removed in the mentioned commit.
So remove the remaining of the pending ordered extents infrastructure.

Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:25 +01:00
Filipe Manana
ce02f03266 Btrfs: remove no longer used logged range variables when logging extents
The logged_start and logged_end variables, at btrfs_log_changed_extents,
were added in commit 8c6c592831 ("btrfs: log csums for all modified
extents"). However since the recent simplification for fsync, which makes
us wait for all ordered extents to complete before logging extents, we
no longer need those variables. Commit a2120a473a ("btrfs: clean up the
left over logged_list usage") forgot to remove them.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:25 +01:00
Linus Torvalds
d089709045 for-4.20-rc5-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAlwH0k8ACgkQxWXV+ddt
 WDtmVg/+Kgvk7laQI9bLEr1/30eG1JfBUMHcVE1F8+g99l28m1Yihjd21j9norVd
 YexBz53jgKou+zV+37CKWBYT1uDPq7CIoxctkdE2j9U0s+RmsqDrhech0dsBsfMR
 jo9VnHJFuJSxGMhjfGnFV+wMtAr4q5aQptNGBl+hR1MvMneroktFv+0WiLmp0Vhj
 +6Iq9WAClJYpgk//cI7nhKkscdzWwRyN3V9RUtdNeYklk1D7l1WprlaPzw22WA9u
 VjQVMICjEaJeIixIwT/D8lz05QgjKlqy1z6faYG5JuJxoYQikuNv/xe2dhZVm35A
 aNsBR0byf3zzuXKQZAlvXJ6/gYPvep+KI7epPyBOdycaqoZza7rQ+/MkSAgQ77Vk
 yBnQuhqiw9Srjh6LDWFkNclVln2wymRKd1SqpZmFPRZre/8L+DU+I8RRaeS2/WcE
 M2k+awRD0oVofbB+hxkFIoR+I1Ggkp2rxQlTT/41tGx0geWC3AGX+TlKSW6ZM5HD
 lRmRXIsVocfighKEnI3Zy7ecZuwCI4/4D6+PQtyhCJb3tDigZ/a4UEYdSVucG8CG
 SuQ5YMn+MyyKT0wH8xkGKDGT15YZ+u9Q/BmPHZRL6sSouFpiCQHA5miD1YA+t1d9
 qMjH6Ycz46Y3j2M0BDfDcm714zoD5/bgeSy5SPC3Zh5lQCGpeIk=
 =VW/F
 -----END PGP SIGNATURE-----

Merge tag 'for-4.20-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fix from David Sterba:
 "A patch in 4.19 introduced a sanity check that was too strict and a
  filesystem cannot be mounted.

  This happens for filesystems with more than 10 devices and has been
  reported by a few users so we need the fix to propagate to stable"

* tag 'for-4.20-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: tree-checker: Don't check max block group size as current max chunk size limit is unreliable
2018-12-05 09:58:17 -08:00
Qu Wenruo
10950929e9 btrfs: tree-checker: Don't check max block group size as current max chunk size limit is unreliable
[BUG]
A completely valid btrfs will refuse to mount, with error message like:
  BTRFS critical (device sdb2): corrupt leaf: root=2 block=239681536 slot=172 \
    bg_start=12018974720 bg_len=10888413184, invalid block group size, \
    have 10888413184 expect (0, 10737418240]

This has been reported several times as the 4.19 kernel is now being
used. The filesystem refuses to mount, but is otherwise ok and booting
4.18 is a workaround.

Btrfs check returns no error, and all kernels used on this fs is later
than 2011, which should all have the 10G size limit commit.

[CAUSE]
For a 12 devices btrfs, we could allocate a chunk larger than 10G due to
stripe stripe bump up.

__btrfs_alloc_chunk()
|- max_stripe_size = 1G
|- max_chunk_size = 10G
|- data_stripe = 11
|- if (1G * 11 > 10G) {
       stripe_size = 976128930;
       stripe_size = round_up(976128930, SZ_16M) = 989855744

However the final stripe_size (989855744) * 11 = 10888413184, which is
still larger than 10G.

[FIX]
For the comprehensive check, we need to do the full check at chunk read
time, and rely on bg <-> chunk mapping to do the check.

We could just skip the length check for now.

Fixes: fce466eab7 ("btrfs: tree-checker: Verify block_group_item")
Cc: stable@vger.kernel.org # v4.19+
Reported-by: Wang Yugui <wangyugui@e16-tech.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-04 15:05:30 +01:00
Linus Torvalds
121b018f8c for-4.20-rc4-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAlv9qYgACgkQxWXV+ddt
 WDupPQ/8DdeLZYQG1tlx2Q+X4/tqPVyAzUjguYzbIY7wvSs1zbEEedENsD8E97yC
 So8ooGnP5B6/dqVidLFQBPwTXN59GybYbrDci8qh0DOJTl3+1r8byD9JC+iofrOF
 tltJkZ+eCOQyyqHHzlzw15uNOg48Qzj1oXvTAcE0P6iN5UcvcfwRW/S39pjsn63C
 63zc09XJ1hmJMJTWZo5h3GoD2UvzrwGXPKXNdv/NWkw9sqQbWdjvZFdqKbvY1VeM
 Oa6FPAPErJqEEEePhpDYbyRcnzjJRMs0deLGpGGChGldQxgMO8ILzBwh/KalfzK7
 h7LIuv1EclUqlyv0mXPqg2E/C3n2UMPqQYFsK9Lt+4Y/PkrWA2jx0lSg0fBl3k8c
 7PyiTqPNPNF8LU48tPEnOzJuNPkquOycgdyQOUpHnS43OF5OLIb6tVyjK4eJHRWw
 xtP65M72qM8T65+gsxYcdm0lvIDLidIwFS+2g4ibKU7EwlYkTC9AHFIAyFKTgxeP
 MpkIH90mKhSxOpbq8RICgr2jWcJZYoFQ4soi1oE+bgyjv75PyhJ0eXOprCh/4KZp
 nkXlPy2skkO9gGecyvr51x/opDEjEkObyOjQm2LhhWYvgcnHgW8Zp1jhQKxabHvz
 iZdVIs/agOerpk1d9ZBHhIXOeS2UcE5klqVRAdf961Wobh+HNis=
 =cCvI
 -----END PGP SIGNATURE-----

Merge tag 'for-4.20-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "Some of these bugs are being hit during testing so we'd like to get
  them merged, otherwise there are usual stability fixes for stable
  trees"

* tag 'for-4.20-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: relocation: set trans to be NULL after ending transaction
  Btrfs: fix race between enabling quotas and subvolume creation
  Btrfs: send, fix infinite loop due to directory rename dependencies
  Btrfs: ensure path name is null terminated at btrfs_control_ioctl
  Btrfs: fix rare chances for data loss when doing a fast fsync
  btrfs: Always try all copies when reading extent buffers
2018-11-28 08:38:20 -08:00
Pan Bian
42a657f576 btrfs: relocation: set trans to be NULL after ending transaction
The function relocate_block_group calls btrfs_end_transaction to release
trans when update_backref_cache returns 1, and then continues the loop
body. If btrfs_block_rsv_refill fails this time, it will jump out the
loop and the freed trans will be accessed. This may result in a
use-after-free bug. The patch assigns NULL to trans after trans is
released so that it will not be accessed.

Fixes: 0647bf564f ("Btrfs: improve forever loop when doing balance relocation")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Pan Bian <bianpan2016@163.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-23 13:47:46 +01:00
Filipe Manana
552f0329c7 Btrfs: fix race between enabling quotas and subvolume creation
We have a race between enabling quotas end subvolume creation that cause
subvolume creation to fail with -EINVAL, and the following diagram shows
how it happens:

              CPU 0                                          CPU 1

 btrfs_ioctl()
  btrfs_ioctl_quota_ctl()
   btrfs_quota_enable()
    mutex_lock(fs_info->qgroup_ioctl_lock)

                                                  btrfs_ioctl()
                                                   create_subvol()
                                                    btrfs_qgroup_inherit()
                                                     -> save fs_info->quota_root
                                                        into quota_root
                                                     -> stores a NULL value
                                                     -> tries to lock the mutex
                                                        qgroup_ioctl_lock
                                                        -> blocks waiting for
                                                           the task at CPU0

   -> sets BTRFS_FS_QUOTA_ENABLED in fs_info
   -> sets quota_root in fs_info->quota_root
      (non-NULL value)

   mutex_unlock(fs_info->qgroup_ioctl_lock)

                                                     -> checks quota enabled
                                                        flag is set
                                                     -> returns -EINVAL because
                                                        fs_info->quota_root was
                                                        NULL before it acquired
                                                        the mutex
                                                        qgroup_ioctl_lock
                                                   -> ioctl returns -EINVAL

Returning -EINVAL to user space will be confusing if all the arguments
passed to the subvolume creation ioctl were valid.

Fix it by grabbing the value from fs_info->quota_root after acquiring
the mutex.

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-22 18:59:59 +01:00
Robbie Ko
a4390aee72 Btrfs: send, fix infinite loop due to directory rename dependencies
When doing an incremental send, due to the need of delaying directory move
(rename) operations we can end up in infinite loop at
apply_children_dir_moves().

An example scenario that triggers this problem is described below, where
directory names correspond to the numbers of their respective inodes.

Parent snapshot:

 .
 |--- 261/
       |--- 271/
             |--- 266/
                   |--- 259/
                   |--- 260/
                   |     |--- 267
                   |
                   |--- 264/
                   |     |--- 258/
                   |           |--- 257/
                   |
                   |--- 265/
                   |--- 268/
                   |--- 269/
                   |     |--- 262/
                   |
                   |--- 270/
                   |--- 272/
                   |     |--- 263/
                   |     |--- 275/
                   |
                   |--- 274/
                         |--- 273/

Send snapshot:

 .
 |-- 275/
      |-- 274/
           |-- 273/
                |-- 262/
                     |-- 269/
                          |-- 258/
                               |-- 271/
                                    |-- 268/
                                         |-- 267/
                                              |-- 270/
                                                   |-- 259/
                                                   |    |-- 265/
                                                   |
                                                   |-- 272/
                                                        |-- 257/
                                                             |-- 260/
                                                             |-- 264/
                                                                  |-- 263/
                                                                       |-- 261/
                                                                            |-- 266/

When processing inode 257 we delay its move (rename) operation because its
new parent in the send snapshot, inode 272, was not yet processed. Then
when processing inode 272, we delay the move operation for that inode
because inode 274 is its ancestor in the send snapshot. Finally we delay
the move operation for inode 274 when processing it because inode 275 is
its new parent in the send snapshot and was not yet moved.

When finishing processing inode 275, we start to do the move operations
that were previously delayed (at apply_children_dir_moves()), resulting in
the following iterations:

1) We issue the move operation for inode 274;

2) Because inode 262 depended on the move operation of inode 274 (it was
   delayed because 274 is its ancestor in the send snapshot), we issue the
   move operation for inode 262;

3) We issue the move operation for inode 272, because it was delayed by
   inode 274 too (ancestor of 272 in the send snapshot);

4) We issue the move operation for inode 269 (it was delayed by 262);

5) We issue the move operation for inode 257 (it was delayed by 272);

6) We issue the move operation for inode 260 (it was delayed by 272);

7) We issue the move operation for inode 258 (it was delayed by 269);

8) We issue the move operation for inode 264 (it was delayed by 257);

9) We issue the move operation for inode 271 (it was delayed by 258);

10) We issue the move operation for inode 263 (it was delayed by 264);

11) We issue the move operation for inode 268 (it was delayed by 271);

12) We verify if we can issue the move operation for inode 270 (it was
    delayed by 271). We detect a path loop in the current state, because
    inode 267 needs to be moved first before we can issue the move
    operation for inode 270. So we delay again the move operation for
    inode 270, this time we will attempt to do it after inode 267 is
    moved;

13) We issue the move operation for inode 261 (it was delayed by 263);

14) We verify if we can issue the move operation for inode 266 (it was
    delayed by 263). We detect a path loop in the current state, because
    inode 270 needs to be moved first before we can issue the move
    operation for inode 266. So we delay again the move operation for
    inode 266, this time we will attempt to do it after inode 270 is
    moved (its move operation was delayed in step 12);

15) We issue the move operation for inode 267 (it was delayed by 268);

16) We verify if we can issue the move operation for inode 266 (it was
    delayed by 270). We detect a path loop in the current state, because
    inode 270 needs to be moved first before we can issue the move
    operation for inode 266. So we delay again the move operation for
    inode 266, this time we will attempt to do it after inode 270 is
    moved (its move operation was delayed in step 12). So here we added
    again the same delayed move operation that we added in step 14;

17) We attempt again to see if we can issue the move operation for inode
    266, and as in step 16, we realize we can not due to a path loop in
    the current state due to a dependency on inode 270. Again we delay
    inode's 266 rename to happen after inode's 270 move operation, adding
    the same dependency to the empty stack that we did in steps 14 and 16.
    The next iteration will pick the same move dependency on the stack
    (the only entry) and realize again there is still a path loop and then
    again the same dependency to the stack, over and over, resulting in
    an infinite loop.

So fix this by preventing adding the same move dependency entries to the
stack by removing each pending move record from the red black tree of
pending moves. This way the next call to get_pending_dir_moves() will
not return anything for the current parent inode.

A test case for fstests, with this reproducer, follows soon.

Signed-off-by: Robbie Ko <robbieko@synology.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
[Wrote changelog with example and more clear explanation]
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-21 17:03:50 +01:00
Filipe Manana
f505754fd6 Btrfs: ensure path name is null terminated at btrfs_control_ioctl
We were using the path name received from user space without checking that
it is null terminated. While btrfs-progs is well behaved and does proper
validation and null termination, someone could call the ioctl and pass
a non-null terminated patch, leading to buffer overrun problems in the
kernel.  The ioctl is protected by CAP_SYS_ADMIN.

So just set the last byte of the path to a null character, similar to what
we do in other ioctls (add/remove/resize device, snapshot creation, etc).

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-14 18:26:20 +01:00
Filipe Manana
aab15e8ec2 Btrfs: fix rare chances for data loss when doing a fast fsync
After the simplification of the fast fsync patch done recently by commit
b5e6c3e170 ("btrfs: always wait on ordered extents at fsync time") and
commit e7175a6927 ("btrfs: remove the wait ordered logic in the
log_one_extent path"), we got a very short time window where we can get
extents logged without writeback completing first or extents logged
without logging the respective data checksums. Both issues can only happen
when doing a non-full (fast) fsync.

As soon as we enter btrfs_sync_file() we trigger writeback, then lock the
inode and then wait for the writeback to complete before starting to log
the inode. However before we acquire the inode's lock and after we started
writeback, it's possible that more writes happened and dirtied more pages.
If that happened and those pages get writeback triggered while we are
logging the inode (for example, the VM subsystem triggering it due to
memory pressure, or another concurrent fsync), we end up seeing the
respective extent maps in the inode's list of modified extents and will
log matching file extent items without waiting for the respective
ordered extents to complete, meaning that either of the following will
happen:

1) We log an extent after its writeback finishes but before its checksums
   are added to the csum tree, leading to -EIO errors when attempting to
   read the extent after a log replay.

2) We log an extent before its writeback finishes.
   Therefore after the log replay we will have a file extent item pointing
   to an unwritten extent (and without the respective data checksums as
   well).

This could not happen before the fast fsync patch simplification, because
for any extent we found in the list of modified extents, we would wait for
its respective ordered extent to finish writeback or collect its checksums
for logging if it did not complete yet.

Fix this by triggering writeback again after acquiring the inode's lock
and before waiting for ordered extents to complete.

Fixes: e7175a6927 ("btrfs: remove the wait ordered logic in the log_one_extent path")
Fixes: b5e6c3e170 ("btrfs: always wait on ordered extents at fsync time")
CC: stable@vger.kernel.org # 4.19+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-13 13:49:43 +01:00
Nikolay Borisov
f8397d69da btrfs: Always try all copies when reading extent buffers
When a metadata read is served the endio routine btree_readpage_end_io_hook
is called which eventually runs the tree-checker. If tree-checker fails
to validate the read eb then it sets EXTENT_BUFFER_CORRUPT flag. This
leads to btree_read_extent_buffer_pages wrongly assuming that all
available copies of this extent buffer are wrong and failing prematurely.
Fix this modify btree_read_extent_buffer_pages to read all copies of
the data.

This failure was exhibitted in xfstests btrfs/124 which would
spuriously fail its balance operations. The reason was that when balance
was run following re-introduction of the missing raid1 disk
__btrfs_map_block would map the read request to stripe 0, which
corresponded to devid 2 (the disk which is being removed in the test):

    item 2 key (FIRST_CHUNK_TREE CHUNK_ITEM 3553624064) itemoff 15975 itemsize 112
	length 1073741824 owner 2 stripe_len 65536 type DATA|RAID1
	io_align 65536 io_width 65536 sector_size 4096
	num_stripes 2 sub_stripes 1
		stripe 0 devid 2 offset 2156920832
		dev_uuid 8466c350-ed0c-4c3b-b17d-6379b445d5c8
		stripe 1 devid 1 offset 3553624064
		dev_uuid 1265d8db-5596-477e-af03-df08eb38d2ca

This caused read requests for a checksum item that to be routed to the
stale disk which triggered the aforementioned logic involving
EXTENT_BUFFER_CORRUPT flag. This then triggered cascading failures of
the balance operation.

Fixes: a826d6dcb3 ("Btrfs: check items for correctness as we search")
CC: stable@vger.kernel.org # 4.4+
Suggested-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-13 01:55:52 +01:00
Linus Torvalds
63a42e1a5c for-4.20-rc1-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAlvoGIUACgkQxWXV+ddt
 WDta6g//UJSLnVskCUwh8VyMdd47QArQnaLJowOH7wQn4Nqj+2hf04mCq/kv05ed
 OneTezzONZc/qW9fiJGS+Dp77ln4JIDA1hWHtb/A4t9pYlksSQllJ3oiDUVsCp3q
 2EbzrjuNz3iQO6TjKlaHX473CLCMQMXS2OXOUnCkF2maMJSdr86oi+j1UiSnud1/
 C7uMYM3hG8nkfEfjjb1COpkS2MmzYcPruF5RDcbT/WOUfylTsjjX1E7rK/ZEqS9P
 SUcp4uoZe9BNoyWMASLaM7oHE82day4X9MwQoCQFRcm0kq4CnRAZ8X4lBl+M70iW
 7Olii/wNZ2SRiJf3jac/rpxoBHvEskXTHyiHTEmdHp4n1L1pL9GzGYIePQcX7uV1
 Tb6ImdUUKCC//fPqyeB7cEk5yxqahmlFD3qZVs6GnQkzKrPE+ChLx+7PgcJC/XVh
 C5ogNmJm+NvFOuTrYk9zSXg85B8gWHescDJrvNKVizIjw3nKmqiC+dXZljhzw+p8
 HscK9EXsiS8jW9ClfJljXzIa4SeA/i7fQGe4tCKfIrCQ+OqUxWpFCEoxygchinfF
 Rw90fJ0jX083oXsnfFcVdQpQ+SLSKka/aIRMvi58WRgLU3trci5NNN4TFg8TYRKP
 xBDF/iF3sqXajc+xsjoqLhLioZL3Pa5VDNuhsFdois9M5JSRekU=
 =K14u
 -----END PGP SIGNATURE-----

Merge tag 'for-4.20-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "Several fixes to recent release (4.19, fixes tagged for stable) and
  other fixes"

* tag 'for-4.20-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  Btrfs: fix missing delayed iputs on unmount
  Btrfs: fix data corruption due to cloning of eof block
  Btrfs: fix infinite loop on inode eviction after deduplication of eof block
  Btrfs: fix deadlock on tree root leaf when finding free extent
  btrfs: avoid link error with CONFIG_NO_AUTO_INLINE
  btrfs: tree-checker: Fix misleading group system information
  Btrfs: fix missing data checksums after a ranged fsync (msync)
  btrfs: fix pinned underflow after transaction aborted
  Btrfs: fix cur_offset in the error case for nocow
2018-11-11 16:54:38 -06:00
Omar Sandoval
d6fd0ae25c Btrfs: fix missing delayed iputs on unmount
There's a race between close_ctree() and cleaner_kthread().
close_ctree() sets btrfs_fs_closing(), and the cleaner stops when it
sees it set, but this is racy; the cleaner might have already checked
the bit and could be cleaning stuff. In particular, if it deletes unused
block groups, it will create delayed iputs for the free space cache
inodes. As of "btrfs: don't run delayed_iputs in commit", we're no
longer running delayed iputs after a commit. Therefore, if the cleaner
creates more delayed iputs after delayed iputs are run in
btrfs_commit_super(), we will leak inodes on unmount and get a busy
inode crash from the VFS.

Fix it by parking the cleaner before we actually close anything. Then,
any remaining delayed iputs will always be handled in
btrfs_commit_super(). This also ensures that the commit in close_ctree()
is really the last commit, so we can get rid of the commit in
cleaner_kthread().

The fstest/generic/475 followed by 476 can trigger a crash that
manifests as a slab corruption caused by accessing the freed kthread
structure by a wake up function. Sample trace:

[ 5657.077612] BUG: unable to handle kernel NULL pointer dereference at 00000000000000cc
[ 5657.079432] PGD 1c57a067 P4D 1c57a067 PUD da10067 PMD 0
[ 5657.080661] Oops: 0000 [#1] PREEMPT SMP
[ 5657.081592] CPU: 1 PID: 5157 Comm: fsstress Tainted: G        W         4.19.0-rc8-default+ #323
[ 5657.083703] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626cc-prebuilt.qemu-project.org 04/01/2014
[ 5657.086577] RIP: 0010:shrink_page_list+0x2f9/0xe90
[ 5657.091937] RSP: 0018:ffffb5c745c8f728 EFLAGS: 00010287
[ 5657.092953] RAX: 0000000000000074 RBX: ffffb5c745c8f830 RCX: 0000000000000000
[ 5657.094590] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff9a8747fdf3d0
[ 5657.095987] RBP: ffffb5c745c8f9e0 R08: 0000000000000000 R09: 0000000000000000
[ 5657.097159] R10: ffff9a8747fdf5e8 R11: 0000000000000000 R12: ffffb5c745c8f788
[ 5657.098513] R13: ffff9a877f6ff2c0 R14: ffff9a877f6ff2c8 R15: dead000000000200
[ 5657.099689] FS:  00007f948d853b80(0000) GS:ffff9a877d600000(0000) knlGS:0000000000000000
[ 5657.101032] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 5657.101953] CR2: 00000000000000cc CR3: 00000000684bd000 CR4: 00000000000006e0
[ 5657.103159] Call Trace:
[ 5657.103776]  shrink_inactive_list+0x194/0x410
[ 5657.104671]  shrink_node_memcg.constprop.84+0x39a/0x6a0
[ 5657.105750]  shrink_node+0x62/0x1c0
[ 5657.106529]  try_to_free_pages+0x1a4/0x500
[ 5657.107408]  __alloc_pages_slowpath+0x2c9/0xb20
[ 5657.108418]  __alloc_pages_nodemask+0x268/0x2b0
[ 5657.109348]  kmalloc_large_node+0x37/0x90
[ 5657.110205]  __kmalloc_node+0x236/0x310
[ 5657.111014]  kvmalloc_node+0x3e/0x70

Fixes: 30928e9baa ("btrfs: don't run delayed_iputs in commit")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add trace ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-07 20:17:45 +01:00
Filipe Manana
ac765f83f1 Btrfs: fix data corruption due to cloning of eof block
We currently allow cloning a range from a file which includes the last
block of the file even if the file's size is not aligned to the block
size. This is fine and useful when the destination file has the same size,
but when it does not and the range ends somewhere in the middle of the
destination file, it leads to corruption because the bytes between the EOF
and the end of the block have undefined data (when there is support for
discard/trimming they have a value of 0x00).

Example:

 $ mkfs.btrfs -f /dev/sdb
 $ mount /dev/sdb /mnt

 $ export foo_size=$((256 * 1024 + 100))
 $ xfs_io -f -c "pwrite -S 0x3c 0 $foo_size" /mnt/foo
 $ xfs_io -f -c "pwrite -S 0xb5 0 1M" /mnt/bar

 $ xfs_io -c "reflink /mnt/foo 0 512K $foo_size" /mnt/bar

 $ od -A d -t x1 /mnt/bar
 0000000 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5
 *
 0524288 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c 3c
 *
 0786528 3c 3c 3c 3c 00 00 00 00 00 00 00 00 00 00 00 00
 0786544 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 *
 0790528 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5 b5
 *
 1048576

The bytes in the range from 786532 (512Kb + 256Kb + 100 bytes) to 790527
(512Kb + 256Kb + 4Kb - 1) got corrupted, having now a value of 0x00 instead
of 0xb5.

This is similar to the problem we had for deduplication that got recently
fixed by commit de02b9f6bb ("Btrfs: fix data corruption when
deduplicating between different files").

Fix this by not allowing such operations to be performed and return the
errno -EINVAL to user space. This is what XFS is doing as well at the VFS
level. This change however now makes us return -EINVAL instead of
-EOPNOTSUPP for cases where the source range maps to an inline extent and
the destination range's end is smaller then the destination file's size,
since the detection of inline extents is done during the actual process of
dropping file extent items (at __btrfs_drop_extents()). Returning the
-EINVAL error is done early on and solely based on the input parameters
(offsets and length) and destination file's size. This makes us consistent
with XFS and anyone else supporting cloning since this case is now checked
at a higher level in the VFS and is where the -EINVAL will be returned
from starting with kernel 4.20 (the VFS changed was introduced in 4.20-rc1
by commit 07d19dc9fb ("vfs: avoid problematic remapping requests into
partial EOF block"). So this change is more geared towards stable kernels,
as it's unlikely the new VFS checks get removed intentionally.

A test case for fstests follows soon, as well as an update to filter
existing tests that expect -EOPNOTSUPP to accept -EINVAL as well.

CC: <stable@vger.kernel.org> # 4.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-06 16:42:41 +01:00
Filipe Manana
11023d3f5f Btrfs: fix infinite loop on inode eviction after deduplication of eof block
If we attempt to deduplicate the last block of a file A into the middle of
a file B, and file A's size is not a multiple of the block size, we end
rounding the deduplication length to 0 bytes, to avoid the data corruption
issue fixed by commit de02b9f6bb ("Btrfs: fix data corruption when
deduplicating between different files"). However a length of zero will
cause the insertion of an extent state with a start value greater (by 1)
then the end value, leading to a corrupt extent state that will trigger a
warning and cause chaos such as an infinite loop during inode eviction.
Example trace:

 [96049.833585] ------------[ cut here ]------------
 [96049.833714] WARNING: CPU: 0 PID: 24448 at fs/btrfs/extent_io.c:436 insert_state+0x101/0x120 [btrfs]
 [96049.833767] CPU: 0 PID: 24448 Comm: xfs_io Not tainted 4.19.0-rc7-btrfs-next-39 #1
 [96049.833768] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014
 [96049.833780] RIP: 0010:insert_state+0x101/0x120 [btrfs]
 [96049.833783] RSP: 0018:ffffafd2c3707af0 EFLAGS: 00010282
 [96049.833785] RAX: 0000000000000000 RBX: 000000000004dfff RCX: 0000000000000006
 [96049.833786] RDX: 0000000000000007 RSI: ffff99045c143230 RDI: ffff99047b2168a0
 [96049.833787] RBP: ffff990457851cd0 R08: 0000000000000001 R09: 0000000000000000
 [96049.833787] R10: ffffafd2c3707ab8 R11: 0000000000000000 R12: ffff9903b93b12c8
 [96049.833788] R13: 000000000004e000 R14: ffffafd2c3707b80 R15: ffffafd2c3707b78
 [96049.833790] FS:  00007f5c14e7d700(0000) GS:ffff99047b200000(0000) knlGS:0000000000000000
 [96049.833791] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 [96049.833792] CR2: 00007f5c146abff8 CR3: 0000000115f4c004 CR4: 00000000003606f0
 [96049.833795] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 [96049.833796] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 [96049.833796] Call Trace:
 [96049.833809]  __set_extent_bit+0x46c/0x6a0 [btrfs]
 [96049.833823]  lock_extent_bits+0x6b/0x210 [btrfs]
 [96049.833831]  ? _raw_spin_unlock+0x24/0x30
 [96049.833841]  ? test_range_bit+0xdf/0x130 [btrfs]
 [96049.833853]  lock_extent_range+0x8e/0x150 [btrfs]
 [96049.833864]  btrfs_double_extent_lock+0x78/0xb0 [btrfs]
 [96049.833875]  btrfs_extent_same_range+0x14e/0x550 [btrfs]
 [96049.833885]  ? rcu_read_lock_sched_held+0x3f/0x70
 [96049.833890]  ? __kmalloc_node+0x2b0/0x2f0
 [96049.833899]  ? btrfs_dedupe_file_range+0x19a/0x280 [btrfs]
 [96049.833909]  btrfs_dedupe_file_range+0x270/0x280 [btrfs]
 [96049.833916]  vfs_dedupe_file_range_one+0xd9/0xe0
 [96049.833919]  vfs_dedupe_file_range+0x131/0x1b0
 [96049.833924]  do_vfs_ioctl+0x272/0x6e0
 [96049.833927]  ? __fget+0x113/0x200
 [96049.833931]  ksys_ioctl+0x70/0x80
 [96049.833933]  __x64_sys_ioctl+0x16/0x20
 [96049.833937]  do_syscall_64+0x60/0x1b0
 [96049.833939]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
 [96049.833941] RIP: 0033:0x7f5c1478ddd7
 [96049.833943] RSP: 002b:00007ffe15b196a8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
 [96049.833945] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5c1478ddd7
 [96049.833946] RDX: 00005625ece322d0 RSI: 00000000c0189436 RDI: 0000000000000004
 [96049.833947] RBP: 0000000000000000 R08: 00007f5c14a46f48 R09: 0000000000000040
 [96049.833948] R10: 0000000000000541 R11: 0000000000000202 R12: 0000000000000000
 [96049.833949] R13: 0000000000000000 R14: 0000000000000004 R15: 00005625ece322d0
 [96049.833954] irq event stamp: 6196
 [96049.833956] hardirqs last  enabled at (6195): [<ffffffff91b00663>] console_unlock+0x503/0x640
 [96049.833958] hardirqs last disabled at (6196): [<ffffffff91a037dd>] trace_hardirqs_off_thunk+0x1a/0x1c
 [96049.833959] softirqs last  enabled at (6114): [<ffffffff92600370>] __do_softirq+0x370/0x421
 [96049.833964] softirqs last disabled at (6095): [<ffffffff91a8dd4d>] irq_exit+0xcd/0xe0
 [96049.833965] ---[ end trace db7b05f01b7fa10c ]---
 [96049.935816] R13: 0000000000000000 R14: 00005562e5259240 R15: 00007ffff092b910
 [96049.935822] irq event stamp: 6584
 [96049.935823] hardirqs last  enabled at (6583): [<ffffffff91b00663>] console_unlock+0x503/0x640
 [96049.935825] hardirqs last disabled at (6584): [<ffffffff91a037dd>] trace_hardirqs_off_thunk+0x1a/0x1c
 [96049.935827] softirqs last  enabled at (6328): [<ffffffff92600370>] __do_softirq+0x370/0x421
 [96049.935828] softirqs last disabled at (6313): [<ffffffff91a8dd4d>] irq_exit+0xcd/0xe0
 [96049.935829] ---[ end trace db7b05f01b7fa123 ]---
 [96049.935840] ------------[ cut here ]------------
 [96049.936065] WARNING: CPU: 1 PID: 24463 at fs/btrfs/extent_io.c:436 insert_state+0x101/0x120 [btrfs]
 [96049.936107] CPU: 1 PID: 24463 Comm: umount Tainted: G        W         4.19.0-rc7-btrfs-next-39 #1
 [96049.936108] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014
 [96049.936117] RIP: 0010:insert_state+0x101/0x120 [btrfs]
 [96049.936119] RSP: 0018:ffffafd2c3637bc0 EFLAGS: 00010282
 [96049.936120] RAX: 0000000000000000 RBX: 000000000004dfff RCX: 0000000000000006
 [96049.936121] RDX: 0000000000000007 RSI: ffff990445cf88e0 RDI: ffff99047b2968a0
 [96049.936122] RBP: ffff990457851cd0 R08: 0000000000000001 R09: 0000000000000000
 [96049.936123] R10: ffffafd2c3637b88 R11: 0000000000000000 R12: ffff9904574301e8
 [96049.936124] R13: 000000000004e000 R14: ffffafd2c3637c50 R15: ffffafd2c3637c48
 [96049.936125] FS:  00007fe4b87e72c0(0000) GS:ffff99047b280000(0000) knlGS:0000000000000000
 [96049.936126] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 [96049.936128] CR2: 00005562e52618d8 CR3: 00000001151c8005 CR4: 00000000003606e0
 [96049.936129] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 [96049.936131] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 [96049.936131] Call Trace:
 [96049.936141]  __set_extent_bit+0x46c/0x6a0 [btrfs]
 [96049.936154]  lock_extent_bits+0x6b/0x210 [btrfs]
 [96049.936167]  btrfs_evict_inode+0x1e1/0x5a0 [btrfs]
 [96049.936172]  evict+0xbf/0x1c0
 [96049.936174]  dispose_list+0x51/0x80
 [96049.936176]  evict_inodes+0x193/0x1c0
 [96049.936180]  generic_shutdown_super+0x3f/0x110
 [96049.936182]  kill_anon_super+0xe/0x30
 [96049.936189]  btrfs_kill_super+0x13/0x100 [btrfs]
 [96049.936191]  deactivate_locked_super+0x3a/0x70
 [96049.936193]  cleanup_mnt+0x3b/0x80
 [96049.936195]  task_work_run+0x93/0xc0
 [96049.936198]  exit_to_usermode_loop+0xfa/0x100
 [96049.936201]  do_syscall_64+0x17f/0x1b0
 [96049.936202]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
 [96049.936204] RIP: 0033:0x7fe4b80cfb37
 [96049.936206] RSP: 002b:00007ffff092b688 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
 [96049.936207] RAX: 0000000000000000 RBX: 00005562e5259060 RCX: 00007fe4b80cfb37
 [96049.936208] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 00005562e525faa0
 [96049.936209] RBP: 00005562e525faa0 R08: 00005562e525f770 R09: 0000000000000015
 [96049.936210] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007fe4b85d1e64
 [96049.936211] R13: 0000000000000000 R14: 00005562e5259240 R15: 00007ffff092b910
 [96049.936211] R13: 0000000000000000 R14: 00005562e5259240 R15: 00007ffff092b910
 [96049.936216] irq event stamp: 6616
 [96049.936219] hardirqs last  enabled at (6615): [<ffffffff91b00663>] console_unlock+0x503/0x640
 [96049.936219] hardirqs last disabled at (6616): [<ffffffff91a037dd>] trace_hardirqs_off_thunk+0x1a/0x1c
 [96049.936222] softirqs last  enabled at (6328): [<ffffffff92600370>] __do_softirq+0x370/0x421
 [96049.936222] softirqs last disabled at (6313): [<ffffffff91a8dd4d>] irq_exit+0xcd/0xe0
 [96049.936223] ---[ end trace db7b05f01b7fa124 ]---

The second stack trace, from inode eviction, is repeated forever due to
the infinite loop during eviction.

This is the same type of problem fixed way back in 2015 by commit
113e828386 ("Btrfs: fix inode eviction infinite loop after extent_same
ioctl") and commit ccccf3d672 ("Btrfs: fix inode eviction infinite loop
after cloning into it").

So fix this by returning immediately if the deduplication range length
gets rounded down to 0 bytes, as there is nothing that needs to be done in
such case.

Example reproducer:

 $ mkfs.btrfs -f /dev/sdb
 $ mount /dev/sdb /mnt

 $ xfs_io -f -c "pwrite -S 0xe6 0 100" /mnt/foo
 $ xfs_io -f -c "pwrite -S 0xe6 0 1M" /mnt/bar

 # Unmount the filesystem and mount it again so that we start without any
 # extent state records when we ask for the deduplication.
 $ umount /mnt
 $ mount /dev/sdb /mnt

 $ xfs_io -c "dedupe /mnt/foo 0 500K 100" /mnt/bar

 # This unmount triggers the infinite loop.
 $ umount /mnt

A test case for fstests will follow soon.

Fixes: de02b9f6bb ("Btrfs: fix data corruption when deduplicating between different files")
CC: <stable@vger.kernel.org> # 4.19+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-06 16:42:37 +01:00
Filipe Manana
4222ea7100 Btrfs: fix deadlock on tree root leaf when finding free extent
When we are writing out a free space cache, during the transaction commit
phase, we can end up in a deadlock which results in a stack trace like the
following:

 schedule+0x28/0x80
 btrfs_tree_read_lock+0x8e/0x120 [btrfs]
 ? finish_wait+0x80/0x80
 btrfs_read_lock_root_node+0x2f/0x40 [btrfs]
 btrfs_search_slot+0xf6/0x9f0 [btrfs]
 ? evict_refill_and_join+0xd0/0xd0 [btrfs]
 ? inode_insert5+0x119/0x190
 btrfs_lookup_inode+0x3a/0xc0 [btrfs]
 ? kmem_cache_alloc+0x166/0x1d0
 btrfs_iget+0x113/0x690 [btrfs]
 __lookup_free_space_inode+0xd8/0x150 [btrfs]
 lookup_free_space_inode+0x5b/0xb0 [btrfs]
 load_free_space_cache+0x7c/0x170 [btrfs]
 ? cache_block_group+0x72/0x3b0 [btrfs]
 cache_block_group+0x1b3/0x3b0 [btrfs]
 ? finish_wait+0x80/0x80
 find_free_extent+0x799/0x1010 [btrfs]
 btrfs_reserve_extent+0x9b/0x180 [btrfs]
 btrfs_alloc_tree_block+0x1b3/0x4f0 [btrfs]
 __btrfs_cow_block+0x11d/0x500 [btrfs]
 btrfs_cow_block+0xdc/0x180 [btrfs]
 btrfs_search_slot+0x3bd/0x9f0 [btrfs]
 btrfs_lookup_inode+0x3a/0xc0 [btrfs]
 ? kmem_cache_alloc+0x166/0x1d0
 btrfs_update_inode_item+0x46/0x100 [btrfs]
 cache_save_setup+0xe4/0x3a0 [btrfs]
 btrfs_start_dirty_block_groups+0x1be/0x480 [btrfs]
 btrfs_commit_transaction+0xcb/0x8b0 [btrfs]

At cache_save_setup() we need to update the inode item of a block group's
cache which is located in the tree root (fs_info->tree_root), which means
that it may result in COWing a leaf from that tree. If that happens we
need to find a free metadata extent and while looking for one, if we find
a block group which was not cached yet we attempt to load its cache by
calling cache_block_group(). However this function will try to load the
inode of the free space cache, which requires finding the matching inode
item in the tree root - if that inode item is located in the same leaf as
the inode item of the space cache we are updating at cache_save_setup(),
we end up in a deadlock, since we try to obtain a read lock on the same
extent buffer that we previously write locked.

So fix this by using the tree root's commit root when searching for a
block group's free space cache inode item when we are attempting to load
a free space cache. This is safe since block groups once loaded stay in
memory forever, as well as their caches, so after they are first loaded
we will never need to read their inode items again. For new block groups,
once they are created they get their ->cached field set to
BTRFS_CACHE_FINISHED meaning we will not need to read their inode item.

Reported-by: Andrew Nelson <andrew.s.nelson@gmail.com>
Link: https://lore.kernel.org/linux-btrfs/CAPTELenq9x5KOWuQ+fa7h1r3nsJG8vyiTH8+ifjURc_duHh2Wg@mail.gmail.com/
Fixes: 9d66e233c7 ("Btrfs: load free space cache if it exists")
Tested-by: Andrew Nelson <andrew.s.nelson@gmail.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-06 16:42:32 +01:00
Arnd Bergmann
7e17916b35 btrfs: avoid link error with CONFIG_NO_AUTO_INLINE
Note: this patch fixes a problem in a feature outside of btrfs ("kernel
hacking: add a config option to disable compiler auto-inlining") and is
applied ahead of time due to cross-subsystem dependencies.

On 32-bit ARM with gcc-8, I see a link error with the addition of the
CONFIG_NO_AUTO_INLINE option:

fs/btrfs/super.o: In function `btrfs_statfs':
super.c:(.text+0x67b8): undefined reference to `__aeabi_uldivmod'
super.c:(.text+0x67fc): undefined reference to `__aeabi_uldivmod'
super.c:(.text+0x6858): undefined reference to `__aeabi_uldivmod'
super.c:(.text+0x6920): undefined reference to `__aeabi_uldivmod'
super.c:(.text+0x693c): undefined reference to `__aeabi_uldivmod'
fs/btrfs/super.o:super.c:(.text+0x6958): more undefined references to `__aeabi_uldivmod' follow

So far this is the only file that shows the behavior, so I'd propose
to just work around it by marking the functions as 'static inline'
that normally get inlined here.

The reference to __aeabi_uldivmod comes from a div_u64() which has an
optimization for a constant division that uses a straight '/' operator
when the result should be known to the compiler. My interpretation is
that as we turn off inlining, gcc still expects the result to be constant
but fails to use that constant value.

Link: https://lkml.kernel.org/r/20181103153941.1881966-1-arnd@arndb.de
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[ add the note ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-06 16:42:08 +01:00
Shaokun Zhang
761333f2f5 btrfs: tree-checker: Fix misleading group system information
block_group_err shows the group system as a decimal value with a '0x'
prefix, which is somewhat misleading.

Fix it to print hexadecimal, as was intended.

Fixes: fce466eab7 ("btrfs: tree-checker: Verify block_group_item")
CC: stable@vger.kernel.org # 4.19+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-06 16:41:53 +01:00
Filipe Manana
008c6753f7 Btrfs: fix missing data checksums after a ranged fsync (msync)
Recently we got a massive simplification for fsync, where for the fast
path we no longer log new extents while their respective ordered extents
are still running.

However that simplification introduced a subtle regression for the case
where we use a ranged fsync (msync). Consider the following example:

               CPU 0                                    CPU 1

                                            mmap write to range [2Mb, 4Mb[
  mmap write to range [512Kb, 1Mb[
  msync range [512K, 1Mb[
    --> triggers fast fsync
        (BTRFS_INODE_NEEDS_FULL_SYNC
         not set)
    --> creates extent map A for this
        range and adds it to list of
        modified extents
    --> starts ordered extent A for
        this range
    --> waits for it to complete

                                            writeback triggered for range
                                            [2Mb, 4Mb[
                                              --> create extent map B and
                                                  adds it to the list of
                                                  modified extents
                                              --> creates ordered extent B

    --> start looking for and logging
        modified extents
    --> logs extent maps A and B
    --> finds checksums for extent A
        in the csum tree, but not for
        extent B
  fsync (msync) finishes

                                              --> ordered extent B
                                                  finishes and its
                                                  checksums are added
                                                  to the csum tree

                                <power cut>

After replaying the log, we have the extent covering the range [2Mb, 4Mb[
but do not have the data checksum items covering that file range.

This happens because at the very beginning of an fsync (btrfs_sync_file())
we start and wait for IO in the given range [512Kb, 1Mb[ and therefore
wait for any ordered extents in that range to complete before we start
logging the extents. However if right before we start logging the extent
in our range [512Kb, 1Mb[, writeback is started for any other dirty range,
such as the range [2Mb, 4Mb[ due to memory pressure or a concurrent fsync
or msync (btrfs_sync_file() starts writeback before acquiring the inode's
lock), an ordered extent is created for that other range and a new extent
map is created to represent that range and added to the inode's list of
modified extents.

That means that we will see that other extent in that list when collecting
extents for logging (done at btrfs_log_changed_extents()) and log the
extent before the respective ordered extent finishes - namely before the
checksum items are added to the checksums tree, which is where
log_extent_csums() looks for the checksums, therefore making us log an
extent without logging its checksums. Before that massive simplification
of fsync, this wasn't a problem because besides looking for checkums in
the checksums tree, we also looked for them in any ordered extent still
running.

The consequence of data checksums missing for a file range is that users
attempting to read the affected file range will get -EIO errors and dmesg
reports the following:

 [10188.358136] BTRFS info (device sdc): no csum found for inode 297 start 57344
 [10188.359278] BTRFS warning (device sdc): csum failed root 5 ino 297 off 57344 csum 0x98f94189 expected csum 0x00000000 mirror 1

So fix this by skipping extents outside of our logging range at
btrfs_log_changed_extents() and leaving them on the list of modified
extents so that any subsequent ranged fsync may collect them if needed.
Also, if we find a hole extent outside of the range still log it, just
to prevent having gaps between extent items after replaying the log,
otherwise fsck will complain when we are not using the NO_HOLES feature
(fstest btrfs/056 triggers such case).

Fixes: e7175a6927 ("btrfs: remove the wait ordered logic in the log_one_extent path")
CC: stable@vger.kernel.org # 4.19+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-06 16:41:40 +01:00
Lu Fengqi
fcd5e74288 btrfs: fix pinned underflow after transaction aborted
When running generic/475, we may get the following warning in dmesg:

[ 6902.102154] WARNING: CPU: 3 PID: 18013 at fs/btrfs/extent-tree.c:9776 btrfs_free_block_groups+0x2af/0x3b0 [btrfs]
[ 6902.109160] CPU: 3 PID: 18013 Comm: umount Tainted: G        W  O      4.19.0-rc8+ #8
[ 6902.110971] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
[ 6902.112857] RIP: 0010:btrfs_free_block_groups+0x2af/0x3b0 [btrfs]
[ 6902.118921] RSP: 0018:ffffc9000459bdb0 EFLAGS: 00010286
[ 6902.120315] RAX: ffff880175050bb0 RBX: ffff8801124a8000 RCX: 0000000000170007
[ 6902.121969] RDX: 0000000000000002 RSI: 0000000000170007 RDI: ffffffff8125fb74
[ 6902.123716] RBP: ffff880175055d10 R08: 0000000000000000 R09: 0000000000000000
[ 6902.125417] R10: 0000000000000000 R11: 0000000000000000 R12: ffff880175055d88
[ 6902.127129] R13: ffff880175050bb0 R14: 0000000000000000 R15: dead000000000100
[ 6902.129060] FS:  00007f4507223780(0000) GS:ffff88017ba00000(0000) knlGS:0000000000000000
[ 6902.130996] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 6902.132558] CR2: 00005623599cac78 CR3: 000000014b700001 CR4: 00000000003606e0
[ 6902.134270] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 6902.135981] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 6902.137836] Call Trace:
[ 6902.138939]  close_ctree+0x171/0x330 [btrfs]
[ 6902.140181]  ? kthread_stop+0x146/0x1f0
[ 6902.141277]  generic_shutdown_super+0x6c/0x100
[ 6902.142517]  kill_anon_super+0x14/0x30
[ 6902.143554]  btrfs_kill_super+0x13/0x100 [btrfs]
[ 6902.144790]  deactivate_locked_super+0x2f/0x70
[ 6902.146014]  cleanup_mnt+0x3b/0x70
[ 6902.147020]  task_work_run+0x9e/0xd0
[ 6902.148036]  do_syscall_64+0x470/0x600
[ 6902.149142]  ? trace_hardirqs_off_thunk+0x1a/0x1c
[ 6902.150375]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[ 6902.151640] RIP: 0033:0x7f45077a6a7b
[ 6902.157324] RSP: 002b:00007ffd589f3e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
[ 6902.159187] RAX: 0000000000000000 RBX: 000055e8eec732b0 RCX: 00007f45077a6a7b
[ 6902.160834] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000055e8eec73490
[ 6902.162526] RBP: 0000000000000000 R08: 000055e8eec734b0 R09: 00007ffd589f26c0
[ 6902.164141] R10: 0000000000000000 R11: 0000000000000246 R12: 000055e8eec73490
[ 6902.165815] R13: 00007f4507ac61a4 R14: 0000000000000000 R15: 00007ffd589f40d8
[ 6902.167553] irq event stamp: 0
[ 6902.168998] hardirqs last  enabled at (0): [<0000000000000000>]           (null)
[ 6902.170731] hardirqs last disabled at (0): [<ffffffff810cd810>] copy_process.part.55+0x3b0/0x1f00
[ 6902.172773] softirqs last  enabled at (0): [<ffffffff810cd810>] copy_process.part.55+0x3b0/0x1f00
[ 6902.174671] softirqs last disabled at (0): [<0000000000000000>]           (null)
[ 6902.176407] ---[ end trace 463138c2986b275c ]---
[ 6902.177636] BTRFS info (device dm-3): space_info 4 has 273465344 free, is not full
[ 6902.179453] BTRFS info (device dm-3): space_info total=276824064, used=4685824, pinned=18446744073708158976, reserved=0, may_use=0, readonly=65536

In the above line there's "pinned=18446744073708158976" which is an
unsigned u64 value of -1392640, an obvious underflow.

When transaction_kthread is running cleanup_transaction(), another
fsstress is running btrfs_commit_transaction(). The
btrfs_finish_extent_commit() may get the same range as
btrfs_destroy_pinned_extent() got, which causes the pinned underflow.

Fixes: d4b450cd4b ("Btrfs: fix race between transaction commit and empty block group removal")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-06 16:41:34 +01:00
Robbie Ko
506481b20e Btrfs: fix cur_offset in the error case for nocow
When the cow_file_range fails, the related resources are unlocked
according to the range [start..end), so the unlock cannot be repeated in
run_delalloc_nocow.

In some cases (e.g. cur_offset <= end && cow_start != -1), cur_offset is
not updated correctly, so move the cur_offset update before
cow_file_range.

  kernel BUG at mm/page-writeback.c:2663!
  Internal error: Oops - BUG: 0 [#1] SMP
  CPU: 3 PID: 31525 Comm: kworker/u8:7 Tainted: P O
  Hardware name: Realtek_RTD1296 (DT)
  Workqueue: writeback wb_workfn (flush-btrfs-1)
  task: ffffffc076db3380 ti: ffffffc02e9ac000 task.ti: ffffffc02e9ac000
  PC is at clear_page_dirty_for_io+0x1bc/0x1e8
  LR is at clear_page_dirty_for_io+0x14/0x1e8
  pc : [<ffffffc00033c91c>] lr : [<ffffffc00033c774>] pstate: 40000145
  sp : ffffffc02e9af4f0
  Process kworker/u8:7 (pid: 31525, stack limit = 0xffffffc02e9ac020)
  Call trace:
  [<ffffffc00033c91c>] clear_page_dirty_for_io+0x1bc/0x1e8
  [<ffffffbffc514674>] extent_clear_unlock_delalloc+0x1e4/0x210 [btrfs]
  [<ffffffbffc4fb168>] run_delalloc_nocow+0x3b8/0x948 [btrfs]
  [<ffffffbffc4fb948>] run_delalloc_range+0x250/0x3a8 [btrfs]
  [<ffffffbffc514c0c>] writepage_delalloc.isra.21+0xbc/0x1d8 [btrfs]
  [<ffffffbffc516048>] __extent_writepage+0xe8/0x248 [btrfs]
  [<ffffffbffc51630c>] extent_write_cache_pages.isra.17+0x164/0x378 [btrfs]
  [<ffffffbffc5185a8>] extent_writepages+0x48/0x68 [btrfs]
  [<ffffffbffc4f5828>] btrfs_writepages+0x20/0x30 [btrfs]
  [<ffffffc00033d758>] do_writepages+0x30/0x88
  [<ffffffc0003ba0f4>] __writeback_single_inode+0x34/0x198
  [<ffffffc0003ba6c4>] writeback_sb_inodes+0x184/0x3c0
  [<ffffffc0003ba96c>] __writeback_inodes_wb+0x6c/0xc0
  [<ffffffc0003bac20>] wb_writeback+0x1b8/0x1c0
  [<ffffffc0003bb0f0>] wb_workfn+0x150/0x250
  [<ffffffc0002b0014>] process_one_work+0x1dc/0x388
  [<ffffffc0002b02f0>] worker_thread+0x130/0x500
  [<ffffffc0002b6344>] kthread+0x10c/0x110
  [<ffffffc000284590>] ret_from_fork+0x10/0x40
  Code: d503201f a9025bb5 a90363b7 f90023b9 (d4210000)

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-06 16:41:04 +01:00
Linus Torvalds
c2aa1a444c vfs: rework data cloning infrastructure
Rework the vfs_clone_file_range and vfs_dedupe_file_range infrastructure to use
 a common .remap_file_range method and supply generic bounds and sanity checking
 functions that are shared with the data write path. The current VFS
 infrastructure has problems with rlimit, LFS file sizes, file time stamps,
 maximum filesystem file sizes, stripping setuid bits, etc and so they are
 addressed in these commits.
 
 We also introduce the ability for the ->remap_file_range methods to return short
 clones so that clones for vfs_copy_file_range() don't get rejected if the entire
 range can't be cloned. It also allows filesystems to sliently skip deduplication
 of partial EOF blocks if they are not capable of doing so without requiring
 errors to be thrown to userspace.
 
 All existing filesystems are converted to user the new .remap_file_range method,
 and both XFS and ocfs2 are modified to make use of the new generic checking
 infrastructure.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJb29gEAAoJEK3oKUf0dfodpOAQAL2VbHjvKXEwNMDTKscSRMmZ
 Z0xXo3gamFKQ+VGOqy2g2lmAYQs9SAnTuCGTJ7zIAp7u+q8gzUy5FzKAwLS4Id6L
 8siaY6nzlicfO04d0MdXnWz0f3xykChgzfdQfVUlUi7WrDioBUECLPmx4a+USsp1
 DQGjLOZfoOAmn2rijdnH9RTEaHqg+8mcTaLN9TRav4gGqrWxldFKXw2y6ouFC7uo
 /hxTRNXR9VI+EdbDelwBNXl9nU9gQA0WLOvRKwgUrtv6bSJohTPsmXt7EbBtNcVR
 cl3zDNc1sLD1bLaRLEUAszI/33wXaaQgom1iB51obIcHHef+JxRNG/j6rUMfzxZI
 VaauGv5EIvtaKN0LTAqVVLQ8t2MQFYfOr8TykmO+1UFog204aKRANdVMHDSjxD/0
 dTGKJGcq+HnKQ+JHDbTdvuXEL8sUUl1FiLjOQbZPw63XmuddLKFUA2TOjXn6htbU
 1h1MG5d9KjGLpabp2BQheczD08NuSmcrOBNt7IoeI3+nxr3HpMwprfB9TyaERy9X
 iEgyVXmjjc9bLLRW7A2wm77aW64NvPs51wKMnvuNgNwnCewrGS6cB8WVj2zbQjH1
 h3f3nku44s9ctNPSBzb/sJLnpqmZQ5t0oSmrMSN+5+En6rNTacoJCzxHRJBA7z/h
 Z+C6y1GTZw0euY6Zjiwu
 =CE/A
 -----END PGP SIGNATURE-----

Merge tag 'xfs-4.20-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull vfs dedup fixes from Dave Chinner:
 "This reworks the vfs data cloning infrastructure.

  We discovered many issues with these interfaces late in the 4.19 cycle
  - the worst of them (data corruption, setuid stripping) were fixed for
  XFS in 4.19-rc8, but a larger rework of the infrastructure fixing all
  the problems was needed. That rework is the contents of this pull
  request.

  Rework the vfs_clone_file_range and vfs_dedupe_file_range
  infrastructure to use a common .remap_file_range method and supply
  generic bounds and sanity checking functions that are shared with the
  data write path. The current VFS infrastructure has problems with
  rlimit, LFS file sizes, file time stamps, maximum filesystem file
  sizes, stripping setuid bits, etc and so they are addressed in these
  commits.

  We also introduce the ability for the ->remap_file_range methods to
  return short clones so that clones for vfs_copy_file_range() don't get
  rejected if the entire range can't be cloned. It also allows
  filesystems to sliently skip deduplication of partial EOF blocks if
  they are not capable of doing so without requiring errors to be thrown
  to userspace.

  Existing filesystems are converted to user the new remap_file_range
  method, and both XFS and ocfs2 are modified to make use of the new
  generic checking infrastructure"

* tag 'xfs-4.20-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (28 commits)
  xfs: remove [cm]time update from reflink calls
  xfs: remove xfs_reflink_remap_range
  xfs: remove redundant remap partial EOF block checks
  xfs: support returning partial reflink results
  xfs: clean up xfs_reflink_remap_blocks call site
  xfs: fix pagecache truncation prior to reflink
  ocfs2: remove ocfs2_reflink_remap_range
  ocfs2: support partial clone range and dedupe range
  ocfs2: fix pagecache truncation prior to reflink
  ocfs2: truncate page cache for clone destination file before remapping
  vfs: clean up generic_remap_file_range_prep return value
  vfs: hide file range comparison function
  vfs: enable remap callers that can handle short operations
  vfs: plumb remap flags through the vfs dedupe functions
  vfs: plumb remap flags through the vfs clone functions
  vfs: make remap_file_range functions take and return bytes completed
  vfs: remap helper should update destination inode metadata
  vfs: pass remap flags to generic_remap_checks
  vfs: pass remap flags to generic_remap_file_range_prep
  vfs: combine the clone and dedupe into a single remap_file_range
  ...
2018-11-02 09:33:08 -07:00
Linus Torvalds
85b5d4bcab for-4.20-part2-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAlvYVlMACgkQxWXV+ddt
 WDv9xxAAmN+R9y+wOKjPkDoM7jr8hRR12YnTC8R4X8oD8QTnSXWOrmfO2prYpe7d
 RyUxpuhqY+q+qvCxkp+BREa86a0zswhn/Z6HfLbHn4CaEhtchkMKR/gFOiYeL2B1
 ZIJtqgnqOGP3N1oxfn3Zr586W3ECUJq+4EUD/1OWCxZHvn1DWWd7L3VL0884hAhE
 kDVWhMdBm0nX1SOet/8haI0N98NLdyltsGdz80ooi65qR52YE4u2IoqXEg2z0AEM
 EApA6vQeOIIuZaRznIl2xFiIMbQCoMRb2sQgwIPmWoXrfboJUHyHfFrKRv5gGUHg
 DXjOXTvVdu9EEqm+1HughwZL/KRkr+OcXHHWwP+v51zsiyfbic+fegpM6a+Z0NjD
 LCo5D1NSLulhpZHr14F3qM27+LYHEC4xxXrrzRoVq4DCoSq7xgj3ip49uXe1F4Rw
 AyLeJGGOp8aqvPiD0BfgMVi4+YhWJUd/ob9Ldn9z+2y0XGQ2FDM58iCt+49+YIQi
 e2ywGaHt3aXghPAo/mvnckfZMLNZ7DJPwA7K6ayJ3N23dqGW2CORkKrGy7xVGoZn
 2AjIN1pSRLlknQJZsa6Yp1mPxnrBQfutTVxxUfKOtmEzydxMVS0g92+Lu/JRb4pu
 F/tpq/lC7dpTvP08EWw0sLjIhLeqMKzbXk38pSfUm39yDgQ10e8=
 =CiDs
 -----END PGP SIGNATURE-----

Merge tag 'for-4.20-part2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull more btrfs updates from David Sterba:
 "This contains a few minor updates and fixes that were under testing or
  arrived shortly after the merge window freeze, mostly stable material"

* tag 'for-4.20-part2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  Btrfs: fix use-after-free when dumping free space
  Btrfs: fix use-after-free during inode eviction
  btrfs: move the dio_sem higher up the callchain
  btrfs: don't run delayed_iputs in commit
  btrfs: fix insert_reserved error handling
  btrfs: only free reserved extent if we didn't insert it
  btrfs: don't use ctl->free_space for max_extent_size
  btrfs: set max_extent_size properly
  btrfs: reset max_extent_size properly
  MAINTAINERS: update my email address for btrfs
  btrfs: delayed-ref: extract find_first_ref_head from find_ref_head
  Btrfs: fix deadlock when writing out free space caches
  Btrfs: fix assertion on fsync of regular file when using no-holes feature
  Btrfs: fix null pointer dereference on compressed write path error
2018-10-30 08:27:13 -07:00
Darrick J. Wong
42ec3d4c02 vfs: make remap_file_range functions take and return bytes completed
Change the remap_file_range functions to take a number of bytes to
operate upon and return the number of bytes they operated on.  This is a
requirement for allowing fs implementations to return short clone/dedupe
results to the user, which will enable us to obey resource limits in a
graceful manner.

A subsequent patch will enable copy_file_range to signal to the
->clone_file_range implementation that it can handle a short length,
which will be returned in the function's return value.  For now the
short return is not implemented anywhere so the behavior won't change --
either copy_file_range manages to clone the entire range or it tries an
alternative.

Neither clone ioctl can take advantage of this, alas.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2018-10-30 10:41:49 +11:00
Darrick J. Wong
2e5dfc99f2 vfs: combine the clone and dedupe into a single remap_file_range
Combine the clone_file_range and dedupe_file_range operations into a
single remap_file_range file operation dispatch since they're
fundamentally the same operation.  The differences between the two can
be made in the prep functions.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2018-10-30 10:41:21 +11:00
Linus Torvalds
dad4f140ed Merge branch 'xarray' of git://git.infradead.org/users/willy/linux-dax
Pull XArray conversion from Matthew Wilcox:
 "The XArray provides an improved interface to the radix tree data
  structure, providing locking as part of the API, specifying GFP flags
  at allocation time, eliminating preloading, less re-walking the tree,
  more efficient iterations and not exposing RCU-protected pointers to
  its users.

  This patch set

   1. Introduces the XArray implementation

   2. Converts the pagecache to use it

   3. Converts memremap to use it

  The page cache is the most complex and important user of the radix
  tree, so converting it was most important. Converting the memremap
  code removes the only other user of the multiorder code, which allows
  us to remove the radix tree code that supported it.

  I have 40+ followup patches to convert many other users of the radix
  tree over to the XArray, but I'd like to get this part in first. The
  other conversions haven't been in linux-next and aren't suitable for
  applying yet, but you can see them in the xarray-conv branch if you're
  interested"

* 'xarray' of git://git.infradead.org/users/willy/linux-dax: (90 commits)
  radix tree: Remove multiorder support
  radix tree test: Convert multiorder tests to XArray
  radix tree tests: Convert item_delete_rcu to XArray
  radix tree tests: Convert item_kill_tree to XArray
  radix tree tests: Move item_insert_order
  radix tree test suite: Remove multiorder benchmarking
  radix tree test suite: Remove __item_insert
  memremap: Convert to XArray
  xarray: Add range store functionality
  xarray: Move multiorder_check to in-kernel tests
  xarray: Move multiorder_shrink to kernel tests
  xarray: Move multiorder account test in-kernel
  radix tree test suite: Convert iteration test to XArray
  radix tree test suite: Convert tag_tagged_items to XArray
  radix tree: Remove radix_tree_clear_tags
  radix tree: Remove radix_tree_maybe_preload_order
  radix tree: Remove split/join code
  radix tree: Remove radix_tree_update_node_t
  page cache: Finish XArray conversion
  dax: Convert page fault handlers to XArray
  ...
2018-10-28 11:35:40 -07:00
Linus Torvalds
4ba9628fe5 Merge branch 'work.lookup' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more ->lookup() cleanups from Al Viro:
 "Some ->lookup() instances are still overcomplicating the life
  for themselves, open-coding the stuff that would be handled by
  d_splice_alias() just fine.

  Simplify a couple of such cases caught this cycle and document
  d_splice_alias() intended use"

* 'work.lookup' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  Document d_splice_alias() calling conventions for ->lookup() users.
  simplify btrfs_lookup()
  clean erofs_lookup()
2018-10-25 12:55:31 -07:00
Filipe Manana
9084cb6a24 Btrfs: fix use-after-free when dumping free space
We were iterating a block group's free space cache rbtree without locking
first the lock that protects it (the free_space_ctl->free_space_offset
rbtree is protected by the free_space_ctl->tree_lock spinlock).

KASAN reported an use-after-free problem when iterating such a rbtree due
to a concurrent rbtree delete:

[ 9520.359168] ==================================================================
[ 9520.359656] BUG: KASAN: use-after-free in rb_next+0x13/0x90
[ 9520.359949] Read of size 8 at addr ffff8800b7ada500 by task btrfs-transacti/1721
[ 9520.360357]
[ 9520.360530] CPU: 4 PID: 1721 Comm: btrfs-transacti Tainted: G             L    4.19.0-rc8-nbor #555
[ 9520.360990] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
[ 9520.362682] Call Trace:
[ 9520.362887]  dump_stack+0xa4/0xf5
[ 9520.363146]  print_address_description+0x78/0x280
[ 9520.363412]  kasan_report+0x263/0x390
[ 9520.363650]  ? rb_next+0x13/0x90
[ 9520.363873]  __asan_load8+0x54/0x90
[ 9520.364102]  rb_next+0x13/0x90
[ 9520.364380]  btrfs_dump_free_space+0x146/0x160 [btrfs]
[ 9520.364697]  dump_space_info+0x2cd/0x310 [btrfs]
[ 9520.364997]  btrfs_reserve_extent+0x1ee/0x1f0 [btrfs]
[ 9520.365310]  __btrfs_prealloc_file_range+0x1cc/0x620 [btrfs]
[ 9520.365646]  ? btrfs_update_time+0x180/0x180 [btrfs]
[ 9520.365923]  ? _raw_spin_unlock+0x27/0x40
[ 9520.366204]  ? btrfs_alloc_data_chunk_ondemand+0x2c0/0x5c0 [btrfs]
[ 9520.366549]  btrfs_prealloc_file_range_trans+0x23/0x30 [btrfs]
[ 9520.366880]  cache_save_setup+0x42e/0x580 [btrfs]
[ 9520.367220]  ? btrfs_check_data_free_space+0xd0/0xd0 [btrfs]
[ 9520.367518]  ? lock_downgrade+0x2f0/0x2f0
[ 9520.367799]  ? btrfs_write_dirty_block_groups+0x11f/0x6e0 [btrfs]
[ 9520.368104]  ? kasan_check_read+0x11/0x20
[ 9520.368349]  ? do_raw_spin_unlock+0xa8/0x140
[ 9520.368638]  btrfs_write_dirty_block_groups+0x2af/0x6e0 [btrfs]
[ 9520.368978]  ? btrfs_start_dirty_block_groups+0x870/0x870 [btrfs]
[ 9520.369282]  ? do_raw_spin_unlock+0xa8/0x140
[ 9520.369534]  ? _raw_spin_unlock+0x27/0x40
[ 9520.369811]  ? btrfs_run_delayed_refs+0x1b8/0x230 [btrfs]
[ 9520.370137]  commit_cowonly_roots+0x4b9/0x610 [btrfs]
[ 9520.370560]  ? commit_fs_roots+0x350/0x350 [btrfs]
[ 9520.370926]  ? btrfs_run_delayed_refs+0x1b8/0x230 [btrfs]
[ 9520.371285]  btrfs_commit_transaction+0x5e5/0x10e0 [btrfs]
[ 9520.371612]  ? btrfs_apply_pending_changes+0x90/0x90 [btrfs]
[ 9520.371943]  ? start_transaction+0x168/0x6c0 [btrfs]
[ 9520.372257]  transaction_kthread+0x21c/0x240 [btrfs]
[ 9520.372537]  kthread+0x1d2/0x1f0
[ 9520.372793]  ? btrfs_cleanup_transaction+0xb50/0xb50 [btrfs]
[ 9520.373090]  ? kthread_park+0xb0/0xb0
[ 9520.373329]  ret_from_fork+0x3a/0x50
[ 9520.373567]
[ 9520.373738] Allocated by task 1804:
[ 9520.373974]  kasan_kmalloc+0xff/0x180
[ 9520.374208]  kasan_slab_alloc+0x11/0x20
[ 9520.374447]  kmem_cache_alloc+0xfc/0x2d0
[ 9520.374731]  __btrfs_add_free_space+0x40/0x580 [btrfs]
[ 9520.375044]  unpin_extent_range+0x4f7/0x7a0 [btrfs]
[ 9520.375383]  btrfs_finish_extent_commit+0x15f/0x4d0 [btrfs]
[ 9520.375707]  btrfs_commit_transaction+0xb06/0x10e0 [btrfs]
[ 9520.376027]  btrfs_alloc_data_chunk_ondemand+0x237/0x5c0 [btrfs]
[ 9520.376365]  btrfs_check_data_free_space+0x81/0xd0 [btrfs]
[ 9520.376689]  btrfs_delalloc_reserve_space+0x25/0x80 [btrfs]
[ 9520.377018]  btrfs_direct_IO+0x42e/0x6d0 [btrfs]
[ 9520.377284]  generic_file_direct_write+0x11e/0x220
[ 9520.377587]  btrfs_file_write_iter+0x472/0xac0 [btrfs]
[ 9520.377875]  aio_write+0x25c/0x360
[ 9520.378106]  io_submit_one+0xaa0/0xdc0
[ 9520.378343]  __se_sys_io_submit+0xfa/0x2f0
[ 9520.378589]  __x64_sys_io_submit+0x43/0x50
[ 9520.378840]  do_syscall_64+0x7d/0x240
[ 9520.379081]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[ 9520.379387]
[ 9520.379557] Freed by task 1802:
[ 9520.379782]  __kasan_slab_free+0x173/0x260
[ 9520.380028]  kasan_slab_free+0xe/0x10
[ 9520.380262]  kmem_cache_free+0xc1/0x2c0
[ 9520.380544]  btrfs_find_space_for_alloc+0x4cd/0x4e0 [btrfs]
[ 9520.380866]  find_free_extent+0xa99/0x17e0 [btrfs]
[ 9520.381166]  btrfs_reserve_extent+0xd5/0x1f0 [btrfs]
[ 9520.381474]  btrfs_get_blocks_direct+0x60b/0xbd0 [btrfs]
[ 9520.381761]  __blockdev_direct_IO+0x10ee/0x58a1
[ 9520.382059]  btrfs_direct_IO+0x25a/0x6d0 [btrfs]
[ 9520.382321]  generic_file_direct_write+0x11e/0x220
[ 9520.382623]  btrfs_file_write_iter+0x472/0xac0 [btrfs]
[ 9520.382904]  aio_write+0x25c/0x360
[ 9520.383172]  io_submit_one+0xaa0/0xdc0
[ 9520.383416]  __se_sys_io_submit+0xfa/0x2f0
[ 9520.383678]  __x64_sys_io_submit+0x43/0x50
[ 9520.383927]  do_syscall_64+0x7d/0x240
[ 9520.384165]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[ 9520.384439]
[ 9520.384610] The buggy address belongs to the object at ffff8800b7ada500
                which belongs to the cache btrfs_free_space of size 72
[ 9520.385175] The buggy address is located 0 bytes inside of
                72-byte region [ffff8800b7ada500, ffff8800b7ada548)
[ 9520.385691] The buggy address belongs to the page:
[ 9520.385957] page:ffffea0002deb680 count:1 mapcount:0 mapping:ffff880108a1d700 index:0x0 compound_mapcount: 0
[ 9520.388030] flags: 0x8100(slab|head)
[ 9520.388281] raw: 0000000000008100 ffffea0002deb608 ffffea0002728808 ffff880108a1d700
[ 9520.388722] raw: 0000000000000000 0000000000130013 00000001ffffffff 0000000000000000
[ 9520.389169] page dumped because: kasan: bad access detected
[ 9520.389473]
[ 9520.389658] Memory state around the buggy address:
[ 9520.389943]  ffff8800b7ada400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 9520.390368]  ffff8800b7ada480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 9520.390796] >ffff8800b7ada500: fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc
[ 9520.391223]                    ^
[ 9520.391461]  ffff8800b7ada580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 9520.391885]  ffff8800b7ada600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 9520.392313] ==================================================================
[ 9520.392772] BTRFS critical (device vdc): entry offset 2258497536, bytes 131072, bitmap no
[ 9520.393247] BUG: unable to handle kernel NULL pointer dereference at 0000000000000011
[ 9520.393705] PGD 800000010dbab067 P4D 800000010dbab067 PUD 107551067 PMD 0
[ 9520.394059] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI
[ 9520.394378] CPU: 4 PID: 1721 Comm: btrfs-transacti Tainted: G    B        L    4.19.0-rc8-nbor #555
[ 9520.394858] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
[ 9520.395350] RIP: 0010:rb_next+0x3c/0x90
[ 9520.396461] RSP: 0018:ffff8801074ff780 EFLAGS: 00010292
[ 9520.396762] RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff81b5ac4c
[ 9520.397115] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000011
[ 9520.397468] RBP: ffff8801074ff7a0 R08: ffffed0021d64ccc R09: ffffed0021d64ccc
[ 9520.397821] R10: 0000000000000001 R11: ffffed0021d64ccb R12: ffff8800b91e0000
[ 9520.398188] R13: ffff8800a3ceba48 R14: ffff8800b627bf80 R15: 0000000000020000
[ 9520.398555] FS:  0000000000000000(0000) GS:ffff88010eb00000(0000) knlGS:0000000000000000
[ 9520.399007] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 9520.399335] CR2: 0000000000000011 CR3: 0000000106b52000 CR4: 00000000000006a0
[ 9520.399679] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 9520.400023] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 9520.400400] Call Trace:
[ 9520.400648]  btrfs_dump_free_space+0x146/0x160 [btrfs]
[ 9520.400974]  dump_space_info+0x2cd/0x310 [btrfs]
[ 9520.401287]  btrfs_reserve_extent+0x1ee/0x1f0 [btrfs]
[ 9520.401609]  __btrfs_prealloc_file_range+0x1cc/0x620 [btrfs]
[ 9520.401952]  ? btrfs_update_time+0x180/0x180 [btrfs]
[ 9520.402232]  ? _raw_spin_unlock+0x27/0x40
[ 9520.402522]  ? btrfs_alloc_data_chunk_ondemand+0x2c0/0x5c0 [btrfs]
[ 9520.402882]  btrfs_prealloc_file_range_trans+0x23/0x30 [btrfs]
[ 9520.403261]  cache_save_setup+0x42e/0x580 [btrfs]
[ 9520.403570]  ? btrfs_check_data_free_space+0xd0/0xd0 [btrfs]
[ 9520.403871]  ? lock_downgrade+0x2f0/0x2f0
[ 9520.404161]  ? btrfs_write_dirty_block_groups+0x11f/0x6e0 [btrfs]
[ 9520.404481]  ? kasan_check_read+0x11/0x20
[ 9520.404732]  ? do_raw_spin_unlock+0xa8/0x140
[ 9520.405026]  btrfs_write_dirty_block_groups+0x2af/0x6e0 [btrfs]
[ 9520.405375]  ? btrfs_start_dirty_block_groups+0x870/0x870 [btrfs]
[ 9520.405694]  ? do_raw_spin_unlock+0xa8/0x140
[ 9520.405958]  ? _raw_spin_unlock+0x27/0x40
[ 9520.406243]  ? btrfs_run_delayed_refs+0x1b8/0x230 [btrfs]
[ 9520.406574]  commit_cowonly_roots+0x4b9/0x610 [btrfs]
[ 9520.406899]  ? commit_fs_roots+0x350/0x350 [btrfs]
[ 9520.407253]  ? btrfs_run_delayed_refs+0x1b8/0x230 [btrfs]
[ 9520.407589]  btrfs_commit_transaction+0x5e5/0x10e0 [btrfs]
[ 9520.407925]  ? btrfs_apply_pending_changes+0x90/0x90 [btrfs]
[ 9520.408262]  ? start_transaction+0x168/0x6c0 [btrfs]
[ 9520.408582]  transaction_kthread+0x21c/0x240 [btrfs]
[ 9520.408870]  kthread+0x1d2/0x1f0
[ 9520.409138]  ? btrfs_cleanup_transaction+0xb50/0xb50 [btrfs]
[ 9520.409440]  ? kthread_park+0xb0/0xb0
[ 9520.409682]  ret_from_fork+0x3a/0x50
[ 9520.410508] Dumping ftrace buffer:
[ 9520.410764]    (ftrace buffer empty)
[ 9520.411007] CR2: 0000000000000011
[ 9520.411297] ---[ end trace 01a0863445cf360a ]---
[ 9520.411568] RIP: 0010:rb_next+0x3c/0x90
[ 9520.412644] RSP: 0018:ffff8801074ff780 EFLAGS: 00010292
[ 9520.412932] RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff81b5ac4c
[ 9520.413274] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000011
[ 9520.413616] RBP: ffff8801074ff7a0 R08: ffffed0021d64ccc R09: ffffed0021d64ccc
[ 9520.414007] R10: 0000000000000001 R11: ffffed0021d64ccb R12: ffff8800b91e0000
[ 9520.414349] R13: ffff8800a3ceba48 R14: ffff8800b627bf80 R15: 0000000000020000
[ 9520.416074] FS:  0000000000000000(0000) GS:ffff88010eb00000(0000) knlGS:0000000000000000
[ 9520.416536] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 9520.416848] CR2: 0000000000000011 CR3: 0000000106b52000 CR4: 00000000000006a0
[ 9520.418477] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 9520.418846] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 9520.419204] Kernel panic - not syncing: Fatal exception
[ 9520.419666] Dumping ftrace buffer:
[ 9520.419930]    (ftrace buffer empty)
[ 9520.420168] Kernel Offset: disabled
[ 9520.420406] ---[ end Kernel panic - not syncing: Fatal exception ]---

Fix this by acquiring the respective lock before iterating the rbtree.

Reported-by: Nikolay Borisov <nborisov@suse.com>
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-22 20:31:22 +02:00
Matthew Wilcox
0a943c65e7 btrfs: Convert page cache to XArray
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Acked-by: David Sterba <dsterba@suse.com>
2018-10-21 10:46:41 -04:00
Matthew Wilcox
10bbd23585 pagevec: Use xa_mark_t
Removes sparse warnings.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:39 -04:00
Filipe Manana
421f0922a2 Btrfs: fix use-after-free during inode eviction
At inode.c:evict_inode_truncate_pages(), when we iterate over the
inode's extent states, we access an extent state record's "state" field
after we unlocked the inode's io tree lock. This can lead to a
use-after-free issue because after we unlock the io tree that extent
state record might have been freed due to being merged into another
adjacent extent state record (a previous inflight bio for a read
operation finished in the meanwhile which unlocked a range in the io
tree and cause a merge of extent state records, as explained in the
comment before the while loop added in commit 6ca0709756 ("Btrfs: fix
hang during inode eviction due to concurrent readahead")).

Fix this by keeping a copy of the extent state's flags in a local
variable and using it after unlocking the io tree.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=201189
Fixes: b9d0b38928 ("btrfs: Add handler for invalidate page")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-19 12:25:33 +02:00
Josef Bacik
c495144bc6 btrfs: move the dio_sem higher up the callchain
We're getting a lockdep splat because we take the dio_sem under the
log_mutex.  What we really need is to protect fsync() from logging an
extent map for an extent we never waited on higher up, so just guard the
whole thing with dio_sem.

======================================================
WARNING: possible circular locking dependency detected
4.18.0-rc4-xfstests-00025-g5de5edbaf1d4 #411 Not tainted
------------------------------------------------------
aio-dio-invalid/30928 is trying to acquire lock:
0000000092621cfd (&mm->mmap_sem){++++}, at: get_user_pages_unlocked+0x5a/0x1e0

but task is already holding lock:
00000000cefe6b35 (&ei->dio_sem){++++}, at: btrfs_direct_IO+0x3be/0x400

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #5 (&ei->dio_sem){++++}:
       lock_acquire+0xbd/0x220
       down_write+0x51/0xb0
       btrfs_log_changed_extents+0x80/0xa40
       btrfs_log_inode+0xbaf/0x1000
       btrfs_log_inode_parent+0x26f/0xa80
       btrfs_log_dentry_safe+0x50/0x70
       btrfs_sync_file+0x357/0x540
       do_fsync+0x38/0x60
       __ia32_sys_fdatasync+0x12/0x20
       do_fast_syscall_32+0x9a/0x2f0
       entry_SYSENTER_compat+0x84/0x96

-> #4 (&ei->log_mutex){+.+.}:
       lock_acquire+0xbd/0x220
       __mutex_lock+0x86/0xa10
       btrfs_record_unlink_dir+0x2a/0xa0
       btrfs_unlink+0x5a/0xc0
       vfs_unlink+0xb1/0x1a0
       do_unlinkat+0x264/0x2b0
       do_fast_syscall_32+0x9a/0x2f0
       entry_SYSENTER_compat+0x84/0x96

-> #3 (sb_internal#2){.+.+}:
       lock_acquire+0xbd/0x220
       __sb_start_write+0x14d/0x230
       start_transaction+0x3e6/0x590
       btrfs_evict_inode+0x475/0x640
       evict+0xbf/0x1b0
       btrfs_run_delayed_iputs+0x6c/0x90
       cleaner_kthread+0x124/0x1a0
       kthread+0x106/0x140
       ret_from_fork+0x3a/0x50

-> #2 (&fs_info->cleaner_delayed_iput_mutex){+.+.}:
       lock_acquire+0xbd/0x220
       __mutex_lock+0x86/0xa10
       btrfs_alloc_data_chunk_ondemand+0x197/0x530
       btrfs_check_data_free_space+0x4c/0x90
       btrfs_delalloc_reserve_space+0x20/0x60
       btrfs_page_mkwrite+0x87/0x520
       do_page_mkwrite+0x31/0xa0
       __handle_mm_fault+0x799/0xb00
       handle_mm_fault+0x7c/0xe0
       __do_page_fault+0x1d3/0x4a0
       async_page_fault+0x1e/0x30

-> #1 (sb_pagefaults){.+.+}:
       lock_acquire+0xbd/0x220
       __sb_start_write+0x14d/0x230
       btrfs_page_mkwrite+0x6a/0x520
       do_page_mkwrite+0x31/0xa0
       __handle_mm_fault+0x799/0xb00
       handle_mm_fault+0x7c/0xe0
       __do_page_fault+0x1d3/0x4a0
       async_page_fault+0x1e/0x30

-> #0 (&mm->mmap_sem){++++}:
       __lock_acquire+0x42e/0x7a0
       lock_acquire+0xbd/0x220
       down_read+0x48/0xb0
       get_user_pages_unlocked+0x5a/0x1e0
       get_user_pages_fast+0xa4/0x150
       iov_iter_get_pages+0xc3/0x340
       do_direct_IO+0xf93/0x1d70
       __blockdev_direct_IO+0x32d/0x1c20
       btrfs_direct_IO+0x227/0x400
       generic_file_direct_write+0xcf/0x180
       btrfs_file_write_iter+0x308/0x58c
       aio_write+0xf8/0x1d0
       io_submit_one+0x3a9/0x620
       __ia32_compat_sys_io_submit+0xb2/0x270
       do_int80_syscall_32+0x5b/0x1a0
       entry_INT80_compat+0x88/0xa0

other info that might help us debug this:

Chain exists of:
  &mm->mmap_sem --> &ei->log_mutex --> &ei->dio_sem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ei->dio_sem);
                               lock(&ei->log_mutex);
                               lock(&ei->dio_sem);
  lock(&mm->mmap_sem);

 *** DEADLOCK ***

1 lock held by aio-dio-invalid/30928:
 #0: 00000000cefe6b35 (&ei->dio_sem){++++}, at: btrfs_direct_IO+0x3be/0x400

stack backtrace:
CPU: 0 PID: 30928 Comm: aio-dio-invalid Not tainted 4.18.0-rc4-xfstests-00025-g5de5edbaf1d4 #411
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014
Call Trace:
 dump_stack+0x7c/0xbb
 print_circular_bug.isra.37+0x297/0x2a4
 check_prev_add.constprop.45+0x781/0x7a0
 ? __lock_acquire+0x42e/0x7a0
 validate_chain.isra.41+0x7f0/0xb00
 __lock_acquire+0x42e/0x7a0
 lock_acquire+0xbd/0x220
 ? get_user_pages_unlocked+0x5a/0x1e0
 down_read+0x48/0xb0
 ? get_user_pages_unlocked+0x5a/0x1e0
 get_user_pages_unlocked+0x5a/0x1e0
 get_user_pages_fast+0xa4/0x150
 iov_iter_get_pages+0xc3/0x340
 do_direct_IO+0xf93/0x1d70
 ? __alloc_workqueue_key+0x358/0x490
 ? __blockdev_direct_IO+0x14b/0x1c20
 __blockdev_direct_IO+0x32d/0x1c20
 ? btrfs_run_delalloc_work+0x40/0x40
 ? can_nocow_extent+0x490/0x490
 ? kvm_clock_read+0x1f/0x30
 ? can_nocow_extent+0x490/0x490
 ? btrfs_run_delalloc_work+0x40/0x40
 btrfs_direct_IO+0x227/0x400
 ? btrfs_run_delalloc_work+0x40/0x40
 generic_file_direct_write+0xcf/0x180
 btrfs_file_write_iter+0x308/0x58c
 aio_write+0xf8/0x1d0
 ? kvm_clock_read+0x1f/0x30
 ? __might_fault+0x3e/0x90
 io_submit_one+0x3a9/0x620
 ? io_submit_one+0xe5/0x620
 __ia32_compat_sys_io_submit+0xb2/0x270
 do_int80_syscall_32+0x5b/0x1a0
 entry_INT80_compat+0x88/0xa0

CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-19 12:20:04 +02:00
Josef Bacik
30928e9baa btrfs: don't run delayed_iputs in commit
This could result in a really bad case where we do something like

evict
  evict_refill_and_join
    btrfs_commit_transaction
      btrfs_run_delayed_iputs
        evict
          evict_refill_and_join
            btrfs_commit_transaction
... forever

We have plenty of other places where we run delayed iputs that are much
safer, let those do the work.

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-19 12:20:03 +02:00
Josef Bacik
80ee54bfe8 btrfs: fix insert_reserved error handling
We were not handling the reserved byte accounting properly for data
references.  Metadata was fine, if it errored out the error paths would
free the bytes_reserved count and pin the extent, but it even missed one
of the error cases.  So instead move this handling up into
run_one_delayed_ref so we are sure that both cases are properly cleaned
up in case of a transaction abort.

CC: stable@vger.kernel.org # 4.18+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-19 12:20:03 +02:00
Josef Bacik
49940bdd57 btrfs: only free reserved extent if we didn't insert it
When we insert the file extent once the ordered extent completes we free
the reserved extent reservation as it'll have been migrated to the
bytes_used counter.  However if we error out after this step we'll still
clear the reserved extent reservation, resulting in a negative
accounting of the reserved bytes for the block group and space info.
Fix this by only doing the free if we didn't successfully insert a file
extent for this extent.

CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-19 12:20:03 +02:00
Josef Bacik
fb5c39d7a8 btrfs: don't use ctl->free_space for max_extent_size
max_extent_size is supposed to be the largest contiguous range for the
space info, and ctl->free_space is the total free space in the block
group.  We need to keep track of these separately and _only_ use the
max_free_space if we don't have a max_extent_size, as that means our
original request was too large to search any of the block groups for and
therefore wouldn't have a max_extent_size set.

CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-19 12:20:03 +02:00
Josef Bacik
ad22cf6ea4 btrfs: set max_extent_size properly
We can't use entry->bytes if our entry is a bitmap entry, we need to use
entry->max_extent_size in that case.  Fix up all the logic to make this
consistent.

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-19 12:20:03 +02:00
Josef Bacik
21a94f7acf btrfs: reset max_extent_size properly
If we use up our block group before allocating a new one we'll easily
get a max_extent_size that's set really really low, which will result in
a lot of fragmentation.  We need to make sure we're resetting the
max_extent_size when we add a new chunk or add new space.

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-19 12:20:03 +02:00
Lu Fengqi
0a9df0df17 btrfs: delayed-ref: extract find_first_ref_head from find_ref_head
The find_ref_head shouldn't return the first entry even if no exact match
is found. So move the hidden behavior to higher level.

Besides, remove the useless local variables in the btrfs_select_ref_head.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
[ reformat comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-17 19:21:00 +02:00
Filipe Manana
5ce555578e Btrfs: fix deadlock when writing out free space caches
When writing out a block group free space cache we can end deadlocking
with ourselves on an extent buffer lock resulting in a warning like the
following:

  [245043.379979] WARNING: CPU: 4 PID: 2608 at fs/btrfs/locking.c:251 btrfs_tree_lock+0x1be/0x1d0 [btrfs]
  [245043.392792] CPU: 4 PID: 2608 Comm: btrfs-transacti Tainted: G
    W I      4.16.8 #1
  [245043.395489] RIP: 0010:btrfs_tree_lock+0x1be/0x1d0 [btrfs]
  [245043.396791] RSP: 0018:ffffc9000424b840 EFLAGS: 00010246
  [245043.398093] RAX: 0000000000000a30 RBX: ffff8807e20a3d20 RCX: 0000000000000001
  [245043.399414] RDX: 0000000000000001 RSI: 0000000000000002 RDI: ffff8807e20a3d20
  [245043.400732] RBP: 0000000000000001 R08: ffff88041f39a700 R09: ffff880000000000
  [245043.402021] R10: 0000000000000040 R11: ffff8807e20a3d20 R12: ffff8807cb220630
  [245043.403296] R13: 0000000000000001 R14: ffff8807cb220628 R15: ffff88041fbdf000
  [245043.404780] FS:  0000000000000000(0000) GS:ffff88082fc80000(0000) knlGS:0000000000000000
  [245043.406050] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [245043.407321] CR2: 00007fffdbdb9f10 CR3: 0000000001c09005 CR4: 00000000000206e0
  [245043.408670] Call Trace:
  [245043.409977]  btrfs_search_slot+0x761/0xa60 [btrfs]
  [245043.411278]  btrfs_insert_empty_items+0x62/0xb0 [btrfs]
  [245043.412572]  btrfs_insert_item+0x5b/0xc0 [btrfs]
  [245043.413922]  btrfs_create_pending_block_groups+0xfb/0x1e0 [btrfs]
  [245043.415216]  do_chunk_alloc+0x1e5/0x2a0 [btrfs]
  [245043.416487]  find_free_extent+0xcd0/0xf60 [btrfs]
  [245043.417813]  btrfs_reserve_extent+0x96/0x1e0 [btrfs]
  [245043.419105]  btrfs_alloc_tree_block+0xfb/0x4a0 [btrfs]
  [245043.420378]  __btrfs_cow_block+0x127/0x550 [btrfs]
  [245043.421652]  btrfs_cow_block+0xee/0x190 [btrfs]
  [245043.422979]  btrfs_search_slot+0x227/0xa60 [btrfs]
  [245043.424279]  ? btrfs_update_inode_item+0x59/0x100 [btrfs]
  [245043.425538]  ? iput+0x72/0x1e0
  [245043.426798]  write_one_cache_group.isra.49+0x20/0x90 [btrfs]
  [245043.428131]  btrfs_start_dirty_block_groups+0x102/0x420 [btrfs]
  [245043.429419]  btrfs_commit_transaction+0x11b/0x880 [btrfs]
  [245043.430712]  ? start_transaction+0x8e/0x410 [btrfs]
  [245043.432006]  transaction_kthread+0x184/0x1a0 [btrfs]
  [245043.433341]  kthread+0xf0/0x130
  [245043.434628]  ? btrfs_cleanup_transaction+0x4e0/0x4e0 [btrfs]
  [245043.435928]  ? kthread_create_worker_on_cpu+0x40/0x40
  [245043.437236]  ret_from_fork+0x1f/0x30
  [245043.441054] ---[ end trace 15abaa2aaf36827f ]---

This is because at write_one_cache_group() when we are COWing a leaf from
the extent tree we end up allocating a new block group (chunk) and,
because we have hit a threshold on the number of bytes reserved for system
chunks, we attempt to finalize the creation of new block groups from the
current transaction, by calling btrfs_create_pending_block_groups().
However here we also need to modify the extent tree in order to insert
a block group item, and if the location for this new block group item
happens to be in the same leaf that we were COWing earlier, we deadlock
since btrfs_search_slot() tries to write lock the extent buffer that we
locked before at write_one_cache_group().

We have already hit similar cases in the past and commit d9a0540a79
("Btrfs: fix deadlock when finalizing block group creation") fixed some
of those cases by delaying the creation of pending block groups at the
known specific spots that could lead to a deadlock. This change reworks
that commit to be more generic so that we don't have to add similar logic
to every possible path that can lead to a deadlock. This is done by
making __btrfs_cow_block() disallowing the creation of new block groups
(setting the transaction's can_flush_pending_bgs to false) before it
attempts to allocate a new extent buffer for either the extent, chunk or
device trees, since those are the trees that pending block creation
modifies. Once the new extent buffer is allocated, it allows creation of
pending block groups to happen again.

This change depends on a recent patch from Josef which is not yet in
Linus' tree, named "btrfs: make sure we create all new block groups" in
order to avoid occasional warnings at btrfs_trans_release_chunk_metadata().

Fixes: d9a0540a79 ("Btrfs: fix deadlock when finalizing block group creation")
CC: stable@vger.kernel.org # 4.4+
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199753
Link: https://lore.kernel.org/linux-btrfs/CAJtFHUTHna09ST-_EEiyWmDH6gAqS6wa=zMNMBsifj8ABu99cw@mail.gmail.com/
Reported-by: E V <eliventer@gmail.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-17 17:46:24 +02:00
Filipe Manana
7ed586d0a8 Btrfs: fix assertion on fsync of regular file when using no-holes feature
When using the NO_HOLES feature and logging a regular file, we were
expecting that if we find an inline extent, that either its size in RAM
(uncompressed and unenconded) matches the size of the file or if it does
not, that it matches the sector size and it represents compressed data.
This assertion does not cover a case where the length of the inline extent
is smaller than the sector size and also smaller the file's size, such
case is possible through fallocate. Example:

  $ mkfs.btrfs -f -O no-holes /dev/sdb
  $ mount /dev/sdb /mnt

  $ xfs_io -f -c "pwrite -S 0xb60 0 21" /mnt/foobar
  $ xfs_io -c "falloc 40 40" /mnt/foobar
  $ xfs_io -c "fsync" /mnt/foobar

In the above example we trigger the assertion because the inline extent's
length is 21 bytes while the file size is 80 bytes. The fallocate() call
merely updated the file's size and did not touch the existing inline
extent, as expected.

So fix this by adjusting the assertion so that an inline extent length
smaller than the file size is valid if the file size is smaller than the
filesystem's sector size.

A test case for fstests follows soon.

Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Fixes: a89ca6f24f ("Btrfs: fix fsync after truncate when no_holes feature is enabled")
CC: stable@vger.kernel.org # 4.14+
Link: https://lore.kernel.org/linux-btrfs/CAE5jQCfRSBC7n4pUTFJcmHh109=gwyT9mFkCOL+NKfzswmR=_Q@mail.gmail.com/
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-17 17:44:53 +02:00
Filipe Manana
3527a018c0 Btrfs: fix null pointer dereference on compressed write path error
At inode.c:compress_file_range(), under the "free_pages_out" label, we can
end up dereferencing the "pages" pointer when it has a NULL value. This
case happens when "start" has a value of 0 and we fail to allocate memory
for the "pages" pointer. When that happens we jump to the "cont" label and
then enter the "if (start == 0)" branch where we immediately call the
cow_file_range_inline() function. If that function returns 0 (success
creating an inline extent) or an error (like -ENOMEM for example) we jump
to the "free_pages_out" label and then access "pages[i]" leading to a NULL
pointer dereference, since "nr_pages" has a value greater than zero at
that point.

Fix this by setting "nr_pages" to 0 when we fail to allocate memory for
the "pages" pointer.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=201119
Fixes: 771ed689d2 ("Btrfs: Optimize compressed writeback and reads")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-17 17:42:46 +02:00
Lu Fengqi
d9352794da btrfs: switch return_bigger to bool in find_ref_head
Using bool is more suitable than int here, and add the comment about the
return_bigger.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:41 +02:00
Lu Fengqi
7c8616278b btrfs: remove fs_info from btrfs_should_throttle_delayed_refs
The avg_delayed_ref_runtime can be referenced from the transaction
handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:41 +02:00
Lu Fengqi
af9b8a0e20 btrfs: remove fs_info from btrfs_check_space_for_delayed_refs
It can be referenced from the transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:41 +02:00
Lu Fengqi
9e920a6f03 btrfs: delayed-ref: pass delayed_refs directly to btrfs_delayed_ref_lock
Since trans is only used for referring to delayed_refs, there is no need
to pass it instead of delayed_refs to btrfs_delayed_ref_lock().

No functional change.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:41 +02:00
Lu Fengqi
5637c74b01 btrfs: delayed-ref: pass delayed_refs directly to btrfs_select_ref_head
Since trans is only used for referring to delayed_refs, there is no need
to pass it instead of delayed_refs to btrfs_select_ref_head().  No
functional change.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:40 +02:00
Lu Fengqi
b90e22ba48 btrfs: qgroup: move the qgroup->members check out from (!qgroup)'s else branch
There is no reason to put this check in (!qgroup)'s else branch because
if qgroup is null, it will goto out directly. So move it out to reduce
indentation level.  No functional change.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:40 +02:00
Qu Wenruo
06bbf67244 btrfs: relocation: Remove redundant tree level check
Commit 581c176041 ("btrfs: Validate child tree block's level and first
key") has made tree block level check mandatory.

So if tree block level doesn't match, we won't get a valid extent
buffer.  The extra WARN_ON() check can be removed completely.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:40 +02:00
Qu Wenruo
98ff7b94e4 btrfs: relocation: Cleanup while loop using rbtree_postorder_for_each_entry_safe
And add one line comment explaining what we're doing for each loop.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:40 +02:00
Qu Wenruo
3628b4ca64 btrfs: qgroup: Avoid calling qgroup functions if qgroup is not enabled
Some qgroup trace events like btrfs_qgroup_release_data() and
btrfs_qgroup_free_delayed_ref() can still be triggered even if qgroup is
not enabled.

This is caused by the lack of qgroup status check before calling some
qgroup functions.  Thankfully the functions can handle quota disabled
case well and just do nothing for qgroup disabled case.

This patch will do earlier check before triggering related trace events.

And for enabled <-> disabled race case:

1) For enabled->disabled case
   Disable will wipe out all qgroups data including reservation and
   excl/rfer. Even if we leak some reservation or numbers, it will
   still be cleared, so nothing will go wrong.

2) For disabled -> enabled case
   Current btrfs_qgroup_release_data() will use extent_io tree to ensure
   we won't underflow reservation. And for delayed_ref we use
   head->qgroup_reserved to record the reserved space, so in that case
   head->qgroup_reserved should be 0 and we won't underflow.

CC: stable@vger.kernel.org # 4.14+
Reported-by: Chris Murphy <lists@colorremedies.com>
Link: https://lore.kernel.org/linux-btrfs/CAJCQCtQau7DtuUUeycCkZ36qjbKuxNzsgqJ7+sJ6W0dK_NLE3w@mail.gmail.com/
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:40 +02:00
Filipe Manana
0f375eed92 Btrfs: fix wrong dentries after fsync of file that got its parent replaced
In a scenario like the following:

  mkdir /mnt/A               # inode 258
  mkdir /mnt/B               # inode 259
  touch /mnt/B/bar           # inode 260

  sync

  mv /mnt/B/bar /mnt/A/bar
  mv -T /mnt/A /mnt/B
  fsync /mnt/B/bar

  <power fail>

After replaying the log we end up with file bar having 2 hard links, both
with the name 'bar' and one in the directory with inode number 258 and the
other in the directory with inode number 259. Also, we end up with the
directory inode 259 still existing and with the directory inode 258 still
named as 'A', instead of 'B'. In this scenario, file 'bar' should only
have one hard link, located at directory inode 258, the directory inode
259 should not exist anymore and the name for directory inode 258 should
be 'B'.

This incorrect behaviour happens because when attempting to log the old
parents of an inode, we skip any parents that no longer exist. Fix this
by forcing a full commit if an old parent no longer exists.

A test case for fstests follows soon.

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:39 +02:00
Filipe Manana
f2d72f42d5 Btrfs: fix warning when replaying log after fsync of a tmpfile
When replaying a log which contains a tmpfile (which necessarily has a
link count of 0) we end up calling inc_nlink(), at
fs/btrfs/tree-log.c:replay_one_buffer(), which produces a warning like
the following:

  [195191.943673] WARNING: CPU: 0 PID: 6924 at fs/inode.c:342 inc_nlink+0x33/0x40
  [195191.943723] CPU: 0 PID: 6924 Comm: mount Not tainted 4.19.0-rc6-btrfs-next-38 #1
  [195191.943724] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014
  [195191.943726] RIP: 0010:inc_nlink+0x33/0x40
  [195191.943728] RSP: 0018:ffffb96e425e3870 EFLAGS: 00010246
  [195191.943730] RAX: 0000000000000000 RBX: ffff8c0d1e6af4f0 RCX: 0000000000000006
  [195191.943731] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8c0d1e6af4f0
  [195191.943731] RBP: 0000000000000097 R08: 0000000000000001 R09: 0000000000000000
  [195191.943732] R10: 0000000000000000 R11: 0000000000000000 R12: ffffb96e425e3a60
  [195191.943733] R13: ffff8c0d10cff0c8 R14: ffff8c0d0d515348 R15: ffff8c0d78a1b3f8
  [195191.943735] FS:  00007f570ee24480(0000) GS:ffff8c0dfb200000(0000) knlGS:0000000000000000
  [195191.943736] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [195191.943737] CR2: 00005593286277c8 CR3: 00000000bb8f2006 CR4: 00000000003606f0
  [195191.943739] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [195191.943740] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [195191.943741] Call Trace:
  [195191.943778]  replay_one_buffer+0x797/0x7d0 [btrfs]
  [195191.943802]  walk_up_log_tree+0x1c1/0x250 [btrfs]
  [195191.943809]  ? rcu_read_lock_sched_held+0x3f/0x70
  [195191.943825]  walk_log_tree+0xae/0x1d0 [btrfs]
  [195191.943840]  btrfs_recover_log_trees+0x1d7/0x4d0 [btrfs]
  [195191.943856]  ? replay_dir_deletes+0x280/0x280 [btrfs]
  [195191.943870]  open_ctree+0x1c3b/0x22a0 [btrfs]
  [195191.943887]  btrfs_mount_root+0x6b4/0x800 [btrfs]
  [195191.943894]  ? rcu_read_lock_sched_held+0x3f/0x70
  [195191.943899]  ? pcpu_alloc+0x55b/0x7c0
  [195191.943906]  ? mount_fs+0x3b/0x140
  [195191.943908]  mount_fs+0x3b/0x140
  [195191.943912]  ? __init_waitqueue_head+0x36/0x50
  [195191.943916]  vfs_kern_mount+0x62/0x160
  [195191.943927]  btrfs_mount+0x134/0x890 [btrfs]
  [195191.943936]  ? rcu_read_lock_sched_held+0x3f/0x70
  [195191.943938]  ? pcpu_alloc+0x55b/0x7c0
  [195191.943943]  ? mount_fs+0x3b/0x140
  [195191.943952]  ? btrfs_remount+0x570/0x570 [btrfs]
  [195191.943954]  mount_fs+0x3b/0x140
  [195191.943956]  ? __init_waitqueue_head+0x36/0x50
  [195191.943960]  vfs_kern_mount+0x62/0x160
  [195191.943963]  do_mount+0x1f9/0xd40
  [195191.943967]  ? memdup_user+0x4b/0x70
  [195191.943971]  ksys_mount+0x7e/0xd0
  [195191.943974]  __x64_sys_mount+0x21/0x30
  [195191.943977]  do_syscall_64+0x60/0x1b0
  [195191.943980]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
  [195191.943983] RIP: 0033:0x7f570e4e524a
  [195191.943986] RSP: 002b:00007ffd83589478 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
  [195191.943989] RAX: ffffffffffffffda RBX: 0000563f335b2060 RCX: 00007f570e4e524a
  [195191.943990] RDX: 0000563f335b2240 RSI: 0000563f335b2280 RDI: 0000563f335b2260
  [195191.943992] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000020
  [195191.943993] R10: 00000000c0ed0000 R11: 0000000000000206 R12: 0000563f335b2260
  [195191.943994] R13: 0000563f335b2240 R14: 0000000000000000 R15: 00000000ffffffff
  [195191.944002] irq event stamp: 8688
  [195191.944010] hardirqs last  enabled at (8687): [<ffffffff9cb004c3>] console_unlock+0x503/0x640
  [195191.944012] hardirqs last disabled at (8688): [<ffffffff9ca037dd>] trace_hardirqs_off_thunk+0x1a/0x1c
  [195191.944018] softirqs last  enabled at (8638): [<ffffffff9cc0a5d1>] __set_page_dirty_nobuffers+0x101/0x150
  [195191.944020] softirqs last disabled at (8634): [<ffffffff9cc26bbe>] wb_wakeup_delayed+0x2e/0x60
  [195191.944022] ---[ end trace 5d6e873a9a0b811a ]---

This happens because the inode does not have the flag I_LINKABLE set,
which is a runtime only flag, not meant to be persisted, set when the
inode is created through open(2) if the flag O_EXCL is not passed to it.
Except for the warning, there are no other consequences (like corruptions
or metadata inconsistencies).

Since it's pointless to replay a tmpfile as it would be deleted in a
later phase of the log replay procedure (it has a link count of 0), fix
this by not logging tmpfiles and if a tmpfile is found in a log (created
by a kernel without this change), skip the replay of the inode.

A test case for fstests follows soon.

Fixes: 471d557afe ("Btrfs: fix loss of prealloc extents past i_size after fsync log replay")
CC: stable@vger.kernel.org # 4.18+
Reported-by: Martin Steigerwald <martin@lichtvoll.de>
Link: https://lore.kernel.org/linux-btrfs/3666619.NTnn27ZJZE@merkaba/
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:39 +02:00
Josef Bacik
ad80cf50c3 btrfs: drop min_size from evict_refill_and_join
We don't need it, rsv->size is set once and never changes throughout
its lifetime, so just use that for the reserve size.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:39 +02:00
Josef Bacik
e187831e18 btrfs: assert on non-empty delayed iputs
I ran into an issue where there was some reference being held on an
inode that I couldn't track.  This assert wasn't triggered, but it at
least rules out we're doing something stupid.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:39 +02:00
Josef Bacik
545e3366db btrfs: make sure we create all new block groups
Allocating new chunks modifies both the extent and chunk tree, which can
trigger new chunk allocations.  So instead of doing list_for_each_safe,
just do while (!list_empty()) so we make sure we don't exit with other
pending bg's still on our list.

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:39 +02:00
Josef Bacik
553cceb496 btrfs: reset max_extent_size on clear in a bitmap
We need to clear the max_extent_size when we clear bits from a bitmap
since it could have been from the range that contains the
max_extent_size.

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:39 +02:00
Josef Bacik
84de76a2fb btrfs: protect space cache inode alloc with GFP_NOFS
If we're allocating a new space cache inode it's likely going to be
under a transaction handle, so we need to use memalloc_nofs_save() in
order to avoid deadlocks, and more importantly lockdep messages that
make xfstests fail.

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:38 +02:00
Josef Bacik
f45c752b65 btrfs: release metadata before running delayed refs
We want to release the unused reservation we have since it refills the
delayed refs reserve, which will make everything go smoother when
running the delayed refs if we're short on our reservation.

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:38 +02:00
Liu Bo
5239834016 Btrfs: kill btrfs_clear_path_blocking
Btrfs's btree locking has two modes, spinning mode and blocking mode,
while searching btree, locking is always acquired in spinning mode and
then converted to blocking mode if necessary, and in some hot paths we may
switch the locking back to spinning mode by btrfs_clear_path_blocking().

When acquiring locks, both of reader and writer need to wait for blocking
readers and writers to complete before doing read_lock()/write_lock().

The problem is that btrfs_clear_path_blocking() needs to switch nodes
in the path to blocking mode at first (by btrfs_set_path_blocking) to
make lockdep happy before doing its actual clearing blocking job.

When switching to blocking mode from spinning mode, it consists of

step 1) bumping up blocking readers counter and
step 2) read_unlock()/write_unlock(),

this has caused serious ping-pong effect if there're a great amount of
concurrent readers/writers, as waiters will be woken up and go to
sleep immediately.

1) Killing this kind of ping-pong results in a big improvement in my 1600k
files creation script,

MNT=/mnt/btrfs
mkfs.btrfs -f /dev/sdf
mount /dev/def $MNT
time fsmark  -D  10000  -S0  -n  100000  -s  0  -L  1 -l /tmp/fs_log.txt \
        -d  $MNT/0  -d  $MNT/1 \
        -d  $MNT/2  -d  $MNT/3 \
        -d  $MNT/4  -d  $MNT/5 \
        -d  $MNT/6  -d  $MNT/7 \
        -d  $MNT/8  -d  $MNT/9 \
        -d  $MNT/10  -d  $MNT/11 \
        -d  $MNT/12  -d  $MNT/13 \
        -d  $MNT/14  -d  $MNT/15

w/o patch:
real    2m27.307s
user    0m12.839s
sys     13m42.831s

w/ patch:
real    1m2.273s
user    0m15.802s
sys     8m16.495s

1.1) latency histogram from funclatency[1]

Overall with the patch, there're ~50% less write lock acquisition and
the 95% max latency that write lock takes also reduces to ~100ms from
>500ms.

--------------------------------------------
w/o patch:
--------------------------------------------
Function = btrfs_tree_lock
     msecs               : count     distribution
         0 -> 1          : 2385222  |****************************************|
         2 -> 3          : 37147    |                                        |
         4 -> 7          : 20452    |                                        |
         8 -> 15         : 13131    |                                        |
        16 -> 31         : 3877     |                                        |
        32 -> 63         : 3900     |                                        |
        64 -> 127        : 2612     |                                        |
       128 -> 255        : 974      |                                        |
       256 -> 511        : 165      |                                        |
       512 -> 1023       : 13       |                                        |

Function = btrfs_tree_read_lock
     msecs               : count     distribution
         0 -> 1          : 6743860  |****************************************|
         2 -> 3          : 2146     |                                        |
         4 -> 7          : 190      |                                        |
         8 -> 15         : 38       |                                        |
        16 -> 31         : 4        |                                        |

--------------------------------------------
w/ patch:
--------------------------------------------
Function = btrfs_tree_lock
     msecs               : count     distribution
         0 -> 1          : 1318454  |****************************************|
         2 -> 3          : 6800     |                                        |
         4 -> 7          : 3664     |                                        |
         8 -> 15         : 2145     |                                        |
        16 -> 31         : 809      |                                        |
        32 -> 63         : 219      |                                        |
        64 -> 127        : 10       |                                        |

Function = btrfs_tree_read_lock
     msecs               : count     distribution
         0 -> 1          : 6854317  |****************************************|
         2 -> 3          : 2383     |                                        |
         4 -> 7          : 601      |                                        |
         8 -> 15         : 92       |                                        |

2) dbench also proves the improvement,
dbench -t 120 -D /mnt/btrfs 16

w/o patch:
Throughput 158.363 MB/sec

w/ patch:
Throughput 449.52 MB/sec

3) xfstests didn't show any additional failures.

One thing to note is that callers may set path->leave_spinning to have
all nodes in the path stay in spinning mode, which means callers are
ready to not sleep before releasing the path, but it won't cause
problems if they don't want to sleep in blocking mode.

[1]: https://github.com/iovisor/bcc/blob/master/tools/funclatency.py

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:38 +02:00
David Sterba
9b142115ed btrfs: dev-replace: remove pointless assert in write unlock
The value of blocking_readers is increased only when the lock is taken
for read, no way we can fail the condition with the write lock.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:38 +02:00
David Sterba
7f8d236ae1 btrfs: dev-replace: move replace members out of fs_info
The replace_wait and bio_counter were mistakenly added to fs_info in
commit c404e0dc2c ("Btrfs: fix use-after-free in the finishing
procedure of the device replace"), but they logically belong to
fs_info::dev_replace. Besides, bio_counter is a very generic name and is
confusing in bare fs_info context.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:38 +02:00
David Sterba
aa144bfeaa btrfs: dev-replace: avoid useless lock on error handling path
The exit sequence in btrfs_dev_replace_start does not allow to simply
add a label to the right place so the error handling after starting
transaction failure jumps there. Currently there's a lock that pairs
with the unlock in the section, which is unnecessary and only raises
questions.  Add a variable to track the locking status and avoid the
extra locking.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:38 +02:00
David Sterba
9f6cbcbb09 btrfs: open code btrfs_after_dev_replace_commit
Too trivial, the purpose can be simply documented in a comment.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:37 +02:00
David Sterba
e37abe9725 btrfs: open code btrfs_dev_replace_stats_inc
The wrapper is too trivial, open coding does not make it less readable.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:37 +02:00
David Sterba
7fb2eced10 btrfs: open code btrfs_dev_replace_clear_lock_blocking
There's a single caller and the function name does not say it's actually
taking the lock, so open coding makes it more explicit.

For now, btrfs_dev_replace_read_lock is used instead of read_lock so
it's paired with the unlocking wrapper in the same block.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:37 +02:00
David Sterba
3280f87457 btrfs: remove btrfs_dev_replace::read_locks
This member seems to be copied from the extent_buffer locking scheme and
is at least used to assert that the read lock/unlock is properly nested.
In some way. While the _inc/_dec are called inside the read lock
section, the asserts are both inside and outside, so the ordering is not
guaranteed and we can see read/inc/dec ordered in any way
(theoretically).

A missing call of btrfs_dev_replace_clear_lock_blocking could cause
unexpected read_locks count, so this at least looks like a valid
assertion, but this will become unnecessary with later updates.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:37 +02:00
Qu Wenruo
f556faa46e btrfs: tree-checker: Check level for leaves and nodes
Although we have tree level check at tree read runtime, it's completely
based on its parent level.
We still need to do accurate level check to avoid invalid tree blocks
sneak into kernel space.

The check itself is simple, for leaf its level should always be 0.
For nodes its level should be in range [1, BTRFS_MAX_LEVEL - 1].

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:37 +02:00
Qu Wenruo
3d0174f78e btrfs: qgroup: Only trace data extents in leaves if we're relocating data block group
For qgroup_trace_extent_swap(), if we find one leaf that needs to be
traced, we will also iterate all file extents and trace them.

This is OK if we're relocating data block groups, but if we're
relocating metadata block groups, balance code itself has ensured that
both subtree of file tree and reloc tree contain the same contents.

That's to say, if we're relocating metadata block groups, all file
extents in reloc and file tree should match, thus no need to trace them.
This should reduce the total number of dirty extents processed in metadata
block group balance.

[[Benchmark]] (with all previous enhancement)
Hardware:
	VM 4G vRAM, 8 vCPUs,
	disk is using 'unsafe' cache mode,
	backing device is SAMSUNG 850 evo SSD.
	Host has 16G ram.

Mkfs parameter:
	--nodesize 4K (To bump up tree size)

Initial subvolume contents:
	4G data copied from /usr and /lib.
	(With enough regular small files)

Snapshots:
	16 snapshots of the original subvolume.
	each snapshot has 3 random files modified.

balance parameter:
	-m

So the content should be pretty similar to a real world root fs layout.

                     | v4.19-rc1    | w/ patchset    | diff (*)
---------------------------------------------------------------
relocated extents    | 22929        | 22851          | -0.3%
qgroup dirty extents | 227757       | 140886         | -38.1%
time (sys)           | 65.253s      | 37.464s        | -42.6%
time (real)          | 74.032s      | 44.722s        | -39.6%

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:36 +02:00
Qu Wenruo
2cd86d309b btrfs: qgroup: Don't trace subtree if we're dropping reloc tree
Reloc tree doesn't contribute to qgroup numbers, as we have accounted
them at balance time (see replace_path()).

Skipping the unneeded subtree tracing should reduce the overhead.

[[Benchmark]]
Hardware:
	VM 4G vRAM, 8 vCPUs,
	disk is using 'unsafe' cache mode,
	backing device is SAMSUNG 850 evo SSD.
	Host has 16G ram.

Mkfs parameter:
	--nodesize 4K (To bump up tree size)

Initial subvolume contents:
	4G data copied from /usr and /lib.
	(With enough regular small files)

Snapshots:
	16 snapshots of the original subvolume.
	each snapshot has 3 random files modified.

balance parameter:
	-m

So the content should be pretty similar to a real world root fs layout.

                     | v4.19-rc1    | w/ patchset    | diff (*)
---------------------------------------------------------------
relocated extents    | 22929        | 22900          | -0.1%
qgroup dirty extents | 227757       | 167139         | -26.6%
time (sys)           | 65.253s      | 50.123s        | -23.2%
time (real)          | 74.032s      | 52.551s        | -29.0%

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:36 +02:00
Qu Wenruo
5f527822be btrfs: qgroup: Use generation-aware subtree swap to mark dirty extents
Before this patch, with quota enabled during balance, we need to mark
the whole subtree dirty for quota.

E.g.
OO = Old tree blocks (from file tree)
NN = New tree blocks (from reloc tree)

        File tree (src)		          Reloc tree (dst)
            OO (a)                              NN (a)
           /  \                                /  \
     (b) OO    OO (c)                    (b) NN    NN (c)
        /  \  /  \                          /  \  /  \
       OO  OO OO OO (d)                    OO  OO OO NN (d)

For old balance + quota case, quota will mark the whole src and dst tree
dirty, including all the 3 old tree blocks in reloc tree.

It's doable for small file tree or new tree blocks are all located at
lower level.

But for large file tree or new tree blocks are all located at higher
level, this will lead to mark the whole tree dirty, and be unbelievably
slow.

This patch will change how we handle such balance with quota enabled
case.

Now we will search from (b) and (c) for any new tree blocks whose
generation is equal to @last_snapshot, and only mark them dirty.

In above case, we only need to trace tree blocks NN(b), NN(c) and NN(d).
(NN(a) will be traced when COW happens for nodeptr modification).  And
also for tree blocks OO(b), OO(c), OO(d). (OO(a) will be traced when COW
happens for nodeptr modification.)

For above case, we could skip 3 tree blocks, but for larger tree, we can
skip tons of unmodified tree blocks, and hugely speed up balance.

This patch will introduce a new function,
btrfs_qgroup_trace_subtree_swap(), which will do the following main
work:

1) Read out real root eb
   And setup basic dst_path for later calls
2) Call qgroup_trace_new_subtree_blocks()
   To trace all new tree blocks in reloc tree and their counter
   parts in the file tree.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:36 +02:00
Qu Wenruo
ea49f3e73c btrfs: qgroup: Introduce function to find all new tree blocks of reloc tree
Introduce new function, qgroup_trace_new_subtree_blocks(), to iterate
all new tree blocks in a reloc tree.
So that qgroup could skip unrelated tree blocks during balance, which
should hugely speedup balance speed when quota is enabled.

The function qgroup_trace_new_subtree_blocks() itself only cares about
new tree blocks in reloc tree.

All its main works are:

1) Read out tree blocks according to parent pointers

2) Do recursive depth-first search
   Will call the same function on all its children tree blocks, with
   search level set to current level -1.
   And will also skip all children whose generation is smaller than
   @last_snapshot.

3) Call qgroup_trace_extent_swap() to trace tree blocks

So although we have parameter list related to source file tree, it's not
used at all, but only passed to qgroup_trace_extent_swap().
Thus despite the tree read code, the core should be pretty short and all
about recursive depth-first search.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:36 +02:00
Qu Wenruo
25982561db btrfs: qgroup: Introduce function to trace two swaped extents
Introduce a new function, qgroup_trace_extent_swap(), which will be used
later for balance qgroup speedup.

The basis idea of balance is swapping tree blocks between reloc tree and
the real file tree.

The swap will happen in highest tree block, but there may be a lot of
tree blocks involved.

For example:
 OO = Old tree blocks
 NN = New tree blocks allocated during balance

          File tree (257)                  Reloc tree for 257
L2              OO                                NN
              /    \                            /    \
L1          OO      OO (a)                    OO      NN (a)
           / \     / \                       / \     / \
L0       OO   OO OO   OO                   OO   OO NN   NN
                 (b)  (c)                          (b)  (c)

When calling qgroup_trace_extent_swap(), we will pass:
@src_eb = OO(a)
@dst_path = [ nodes[1] = NN(a), nodes[0] = NN(c) ]
@dst_level = 0
@root_level = 1

In that case, qgroup_trace_extent_swap() will search from OO(a) to
reach OO(c), then mark both OO(c) and NN(c) as qgroup dirty.

The main work of qgroup_trace_extent_swap() can be split into 3 parts:

1) Tree search from @src_eb
   It should acts as a simplified btrfs_search_slot().
   The key for search can be extracted from @dst_path->nodes[dst_level]
   (first key).

2) Mark the final tree blocks in @src_path and @dst_path qgroup dirty
   NOTE: In above case, OO(a) and NN(a) won't be marked qgroup dirty.
   They should be marked during preivous (@dst_level = 1) iteration.

3) Mark file extents in leaves dirty
   We don't have good way to pick out new file extents only.
   So we still follow the old method by scanning all file extents in
   the leave.

This function can free us from keeping two pathes, thus later we only need
to care about how to iterate all new tree blocks in reloc tree.

Signed-off-by: Qu Wenruo <wqu@suse.com>
[ copy changelog to function comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:36 +02:00
Qu Wenruo
c337e7b02f btrfs: qgroup: Introduce trace event to analyse the number of dirty extents accounted
Number of qgroup dirty extents is directly linked to the performance
overhead, so add a new trace event, trace_qgroup_num_dirty_extents(), to
record how many dirty extents is processed in
btrfs_qgroup_account_extents().

This will be pretty handy to analyze later balance performance
improvement.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:36 +02:00
Qu Wenruo
fa6ac71524 btrfs: relocation: Add basic extent backref related comments for build_backref_tree
fs/btrfs/relocation.c:build_backref_tree() is some code from 2009 era,
although it works pretty fine, it's not that easy to understand.
Especially combined with the complex btrfs backref format.

This patch adds some basic comment for the backref build part of the
code, making it less hard to read, at least for backref searching part.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:35 +02:00
Omar Sandoval
4779cc0424 Btrfs: get rid of btrfs_symlink_aops
The only aops we define for symlinks are identical to the aops for
regular files. This has been the case since symlink support was added in
commit 2b8d99a723 ("Btrfs: symlinks and hard links"). As far as I can
tell, there wasn't a good reason to have separate aops then, and there
isn't now, so let's just do what most other filesystems do and reuse the
same structure.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:35 +02:00
Chris Mason
7703bdd8d2 Btrfs: don't clean dirty pages during buffered writes
During buffered writes, we follow this basic series of steps:

again:
	lock all the pages
	wait for writeback on all the pages
	Take the extent range lock
	wait for ordered extents on the whole range
	clean all the pages

	if (copy_from_user_in_atomic() hits a fault) {
		drop our locks
		goto again;
	}

	dirty all the pages
	release all the locks

The extra waiting, cleaning and locking are there to make sure we don't
modify pages in flight to the drive, after they've been crc'd.

If some of the pages in the range were already dirty when the write
began, and we need to goto again, we create a window where a dirty page
has been cleaned and unlocked.  It may be reclaimed before we're able to
lock it again, which means we'll read the old contents off the drive and
lose any modifications that had been pending writeback.

We don't actually need to clean the pages.  All of the other locking in
place makes sure we don't start IO on the pages, so we can just leave
them dirty for the duration of the write.

Fixes: 73d59314e6 (the original btrfs merge)
CC: stable@vger.kernel.org # v4.4+
Signed-off-by: Chris Mason <clm@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:35 +02:00
David Sterba
818255feec btrfs: use common helper instead of open coding a bit test
The helper does the same math and we take care about the special case
when flags is 0 too.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:35 +02:00
Nikolay Borisov
0110a4c434 btrfs: refactor __btrfs_run_delayed_refs loop
Refactor the delayed refs loop by using the newly introduced
btrfs_run_delayed_refs_for_head function. This greatly simplifies
__btrfs_run_delayed_refs and makes it more obvious what is happening.

We now have 1 loop which iterates the existing delayed_heads and then
each selected ref head is processed by the new helper. All existing
semantics of the code are preserved so no functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:35 +02:00
Nikolay Borisov
e726138676 btrfs: Factor out loop processing all refs of a head
This patch introduces a new helper encompassing the implicit inner loop
in __btrfs_run_delayed_refs which processes all the refs for a given
head. The code is mostly copy/paste, the only difference is that if we
detect a newer reference then -EAGAIN is returned so that callers can
react correctly.

Also, at the end of the loop the head is relocked and
btrfs_merge_delayed_refs is run again to retain the pre-refactoring
semantics.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:35 +02:00
Nikolay Borisov
b1cdbcb53a btrfs: Factor out ref head locking code in __btrfs_run_delayed_refs
This is in preparation to refactor the giant loop in
__btrfs_run_delayed_refs. As a first step define a new function
which implements acquiring a reference to a btrfs_delayed_refs_head and
use it. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:34 +02:00
David Sterba
b2fa11547b btrfs: tests: polish ifdefs around testing helper
Avoid the inline ifdefs and use two sections for self-tests enabled and
disabled.

Though there could be no ifdef and unconditional test_bit of
BTRFS_FS_STATE_DUMMY_FS_INFO, the static inline can help to optimize out
any code that would depend on conditions using btrfs_is_testing.

As this is only for the testing code, drop unlikely().

Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:34 +02:00
David Sterba
a654666a34 btrfs: tests: group declarations of self-test helpers
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:34 +02:00
David Sterba
57ec5fb478 btrfs: tests: move testing members of struct btrfs_root to the end
The data used only for tests are better placed at the end of the
structure so that they don't change the structure layout. All new
members of btrfs_root should be placed before.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:34 +02:00
David Sterba
9c36396c2a btrfs: tests: add separate stub for find_lock_delalloc_range
The helper find_lock_delalloc_range is now conditionally built static,
dpending on whether the self-tests are enabled or not. There's a macro
that is supposed to hide the export, used only once. To discourage
further use, drop it an add a public wrapper for the helper needed by
tests.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:34 +02:00
Liu Bo
ecf160b424 Btrfs: preftree: use rb_first_cached
rb_first_cached() trades an extra pointer "leftmost" for doing the same
job as rb_first() but in O(1).

While resolving indirect refs and missing refs, it always looks for the
first rb entry in a while loop, it's helpful to use rb_first_cached
instead.

For more details about the optimization see patch "Btrfs: delayed-refs:
use rb_first_cached for href_root".

Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:33 +02:00
Liu Bo
07e1ce096d Btrfs: extent_map: use rb_first_cached
rb_first_cached() trades an extra pointer "leftmost" for doing the
same job as rb_first() but in O(1).

As evict_inode_truncate_pages() removes all extent mapping by always
looking for the first rb entry, it's helpful to use rb_first_cached
instead.

For more details about the optimization see patch "Btrfs: delayed-refs:
use rb_first_cached for href_root".

Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:33 +02:00
Liu Bo
03a1d4c891 Btrfs: delayed-inode: use rb_first_cached for ins_root and del_root
rb_first_cached() trades an extra pointer "leftmost" for doing the same job as
rb_first() but in O(1).

Functions manipulating delayed_item need to get the first entry, this converts
it to use rb_first_cached().

For more details about the optimization see patch "Btrfs: delayed-refs:
use rb_first_cached for href_root".

Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:33 +02:00
Liu Bo
e3d0396563 Btrfs: delayed-refs: use rb_first_cached for ref_tree
rb_first_cached() trades an extra pointer "leftmost" for doing the same
job as rb_first() but in O(1).

Functions manipulating href->ref_tree need to get the first entry, this
converts href->ref_tree to use rb_first_cached().

For more details about the optimization see patch "Btrfs: delayed-refs:
use rb_first_cached for href_root".

Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:33 +02:00
Liu Bo
5c9d028b3b Btrfs: delayed-refs: use rb_first_cached for href_root
rb_first_cached() trades an extra pointer "leftmost" for doing the same
job as rb_first() but in O(1).

Functions manipulating href_root need to get the first entry, this
converts href_root to use rb_first_cached().

This patch is first in the sequenct of similar updates to other rbtrees
and this is analysis of the expected behaviour and improvements.

There's a common pattern:

while (node = rb_first) {
        entry = rb_entry(node)
        next = rb_next(node)
        rb_erase(node)
        cleanup(entry)
}

rb_first needs to traverse the tree up to logN depth, rb_erase can
completely reshuffle the tree. With the caching we'll skip the traversal
in rb_first.  That's a cached memory access vs looped pointer
dereference trade-off that IMHO has a clear winner.

Measurements show there's not much difference in a sample tree with
10000 nodes: 4.5s / rb_first and 4.8s / rb_first_cached. Real effects of
caching and pointer chasing are unpredictable though.

Further optimzations can be done to avoid the expensive rb_erase step.
In some cases it's ok to process the nodes in any order, so the tree can
be traversed in post-order, not rebalancing the children nodes and just
calling free. Care must be taken regarding the next node.

Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog from mail discussions ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:33 +02:00
Josef Bacik
3aa7c7a31c btrfs: wait on caching when putting the bg cache
While testing my backport I noticed there was a panic if I ran
generic/416 generic/417 generic/418 all in a row.  This just happened to
uncover a race where we had outstanding IO after we destroy all of our
workqueues, and then we'd go to queue the endio work on those free'd
workqueues.

This is because we aren't waiting for the caching threads to be done
before freeing everything up, so to fix this make sure we wait on any
outstanding caching that's being done before we free up the block group,
so we're sure to be done with all IO by the time we get to
btrfs_stop_all_workers().  This fixes the panic I was seeing
consistently in testing.

------------[ cut here ]------------
kernel BUG at fs/btrfs/volumes.c:6112!
SMP PTI
Modules linked in:
CPU: 1 PID: 27165 Comm: kworker/u4:7 Not tainted 4.16.0-02155-g3553e54a578d-dirty #875
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014
Workqueue: btrfs-cache btrfs_cache_helper
RIP: 0010:btrfs_map_bio+0x346/0x370
RSP: 0000:ffffc900061e79d0 EFLAGS: 00010202
RAX: 0000000000000000 RBX: ffff880071542e00 RCX: 0000000000533000
RDX: ffff88006bb74380 RSI: 0000000000000008 RDI: ffff880078160000
RBP: 0000000000000001 R08: ffff8800781cd200 R09: 0000000000503000
R10: ffff88006cd21200 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffff8800781cd200 R15: ffff880071542e00
FS:  0000000000000000(0000) GS:ffff88007fd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000817ffc4 CR3: 0000000078314000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 btree_submit_bio_hook+0x8a/0xd0
 submit_one_bio+0x5d/0x80
 read_extent_buffer_pages+0x18a/0x320
 btree_read_extent_buffer_pages+0xbc/0x200
 ? alloc_extent_buffer+0x359/0x3e0
 read_tree_block+0x3d/0x60
 read_block_for_search.isra.30+0x1a5/0x360
 btrfs_search_slot+0x41b/0xa10
 btrfs_next_old_leaf+0x212/0x470
 caching_thread+0x323/0x490
 normal_work_helper+0xc5/0x310
 process_one_work+0x141/0x340
 worker_thread+0x44/0x3c0
 kthread+0xf8/0x130
 ? process_one_work+0x340/0x340
 ? kthread_bind+0x10/0x10
 ret_from_fork+0x35/0x40
RIP: btrfs_map_bio+0x346/0x370 RSP: ffffc900061e79d0
---[ end trace 827eb13e50846033 ]---
Kernel panic - not syncing: Fatal exception
Kernel Offset: disabled
---[ end Kernel panic - not syncing: Fatal exception

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:33 +02:00
Jeff Mahoney
fee7acc361 btrfs: keep trim from interfering with transaction commits
Commit 499f377f49 (btrfs: iterate over unused chunk space in FITRIM)
fixed free space trimming, but introduced latency when it was running.
This is due to it pinning the transaction using both a incremented
refcount and holding the commit root sem for the duration of a single
trim operation.

This was to ensure safety but it's unnecessary.  We already hold the the
chunk mutex so we know that the chunk we're using can't be allocated
while we're trimming it.

In order to check against chunks allocated already in this transaction,
we need to check the pending chunks list.  To to that safely without
joining the transaction (or attaching than then having to commit it) we
need to ensure that the dev root's commit root doesn't change underneath
us and the pending chunk lists stays around until we're done with it.

We can ensure the former by holding the commit root sem and the latter
by pinning the transaction.  We do this now, but the critical section
covers the trim operation itself and we don't need to do that.

This patch moves the pinning and unpinning logic into helpers and unpins
the transaction after performing the search and check for pending
chunks.

Limiting the critical section of the transaction pinning improves the
latency substantially on slower storage (e.g. image files over NFS).

Fixes: 499f377f49 ("btrfs: iterate over unused chunk space in FITRIM")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:32 +02:00
Jeff Mahoney
0be88e367f btrfs: don't attempt to trim devices that don't support it
We check whether any device the file system is using supports discard in
the ioctl call, but then we attempt to trim free extents on every device
regardless of whether discard is supported.  Due to the way we mask off
EOPNOTSUPP, we can end up issuing the trim operations on each free range
on devices that don't support it, just wasting time.

Fixes: 499f377f49 ("btrfs: iterate over unused chunk space in FITRIM")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:32 +02:00
Jeff Mahoney
d4e329de5e btrfs: iterate all devices during trim, instead of fs_devices::alloc_list
btrfs_trim_fs iterates over the fs_devices->alloc_list while holding the
device_list_mutex.  The problem is that ->alloc_list is protected by the
chunk mutex.  We don't want to hold the chunk mutex over the trim of the
entire file system.  Fortunately, the ->dev_list list is protected by
the dev_list mutex and while it will give us all devices, including
read-only devices, we already just skip the read-only devices.  Then we
can continue to take and release the chunk mutex while scanning each
device.

Fixes: 499f377f49 ("btrfs: iterate over unused chunk space in FITRIM")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:32 +02:00
Qu Wenruo
6ba9fc8e62 btrfs: Ensure btrfs_trim_fs can trim the whole filesystem
[BUG]
fstrim on some btrfs only trims the unallocated space, not trimming any
space in existing block groups.

[CAUSE]
Before fstrim_range passed to btrfs_trim_fs(), it gets truncated to
range [0, super->total_bytes).  So later btrfs_trim_fs() will only be
able to trim block groups in range [0, super->total_bytes).

While for btrfs, any bytenr aligned to sectorsize is valid, since btrfs
uses its logical address space, there is nothing limiting the location
where we put block groups.

For filesystem with frequent balance, it's quite easy to relocate all
block groups and bytenr of block groups will start beyond
super->total_bytes.

In that case, btrfs will not trim existing block groups.

[FIX]
Just remove the truncation in btrfs_ioctl_fitrim(), so btrfs_trim_fs()
can get the unmodified range, which is normally set to [0, U64_MAX].

Reported-by: Chris Murphy <lists@colorremedies.com>
Fixes: f4c697e640 ("btrfs: return EINVAL if start > total_bytes in fitrim ioctl")
CC: <stable@vger.kernel.org> # v4.4+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:32 +02:00
Qu Wenruo
93bba24d4b btrfs: Enhance btrfs_trim_fs function to handle error better
Function btrfs_trim_fs() doesn't handle errors in a consistent way. If
error happens when trimming existing block groups, it will skip the
remaining blocks and continue to trim unallocated space for each device.

The return value will only reflect the final error from device trimming.

This patch will fix such behavior by:

1) Recording the last error from block group or device trimming
   The return value will also reflect the last error during trimming.
   Make developer more aware of the problem.

2) Continuing trimming if possible
   If we failed to trim one block group or device, we could still try
   the next block group or device.

3) Report number of failures during block group and device trimming
   It would be less noisy, but still gives user a brief summary of
   what's going wrong.

Such behavior can avoid confusion for cases like failure to trim the
first block group and then only unallocated space is trimmed.

Reported-by: Chris Murphy <lists@colorremedies.com>
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add bg_ret and dev_ret to the messages ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:32 +02:00
Jeff Mahoney
5c06147128 btrfs: fix error handling in btrfs_dev_replace_start
When we fail to start a transaction in btrfs_dev_replace_start, we leave
dev_replace->replace_start set to STARTED but clear ->srcdev and
->tgtdev.  Later, that can result in an Oops in
btrfs_dev_replace_progress when having state set to STARTED or SUSPENDED
implies that ->srcdev is valid.

Also fix error handling when the state is already STARTED or SUSPENDED
while starting.  That, too, will clear ->srcdev and ->tgtdev even though
it doesn't own them.  This should be an impossible case to hit since we
should be protected by the BTRFS_FS_EXCL_OP bit being set.  Let's add an
ASSERT there while we're at it.

Fixes: e93c89c1aa (Btrfs: add new sources for device replace code)
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:31 +02:00
zhong jiang
c1766dd782 btrfs: change remove_extent_mapping to return void
remove_extent_mapping uses the variable "ret" for return value, but it
is not modified after initialzation. Further, I find that any of the
callers do not handle the return value and the callees are only simple
functions so the return values does not need to be passed.

Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:31 +02:00
Nikolay Borisov
315bed43fe btrfs: handle error of get_old_root
In btrfs_search_old_slot get_old_root is always used with the assumption
it cannot fail. However, this is not true in rare circumstance it can
fail and return null. This will lead to null point dereference when the
header is read. Fix this by checking the return value and properly
handling NULL by setting ret to -EIO and returning gracefully.

Coverity-id: 1087503
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:31 +02:00
Nikolay Borisov
28bee48982 btrfs: Remove logically dead code from btrfs_orphan_cleanup
In btrfs_orphan_cleanup the final 'if (ret) goto out' cannot ever be
executed. This is due to the last assignment to 'ret' depending on the
return value of btrfs_iget. If an error other than -ENOENT is returned
then the loop is prematurely terminated by 'goto out'.  On the other
hand, if the error value is ENOENT then a subsequent if branch is
executed that always re-assigns 'ret' and in case it's an error just
terminates the loop. No functional changes.

Coverity-id: 1437392
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:31 +02:00
Liu Bo
4183c52ce8 Btrfs: remove wait_ordered_range in btrfs_evict_inode
When we delete an inode,

btrfs_evict_inode() {
    truncate_inode_pages_final()
        truncate_inode_pages_range()
            lock_page()
            truncate_cleanup_page()
                 btrfs_invalidatepage()
                      wait_on_page_writeback
                           btrfs_lookup_ordered_range()
                 cancel_dirty_page()
           unlock_page()
     ...
     btrfs_wait_ordered_range()
     ...

As VFS has called ->invalidatepage() to get all ordered extents done (if
there are any) and truncated all page cache pages (no dirty pages to
writeback after this step), wait_ordered_range() is just a noop.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:31 +02:00
Liu Bo
abb57ef3ff Btrfs: skip set_page_dirty if eb pages are already dirty
As long as @eb is marked with EXTENT_BUFFER_DIRTY, all of its pages
are dirty, so no need to set pages dirty again.

Ftrace showed that the loop took 10us on my dev box, so removing this
can save us at least 10us if eb is already dirty and otherwise avoid a
potentially expensive calls to set_page_dirty.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:31 +02:00
Liu Bo
51995c399b Btrfs: assert page dirty bit on extent buffer pages
Just in case that someone breaks the rule that pages are dirty as long
as eb is dirty. The next patch will dirty the pages conditionally.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:30 +02:00
Liu Bo
98e6b1eb40 Btrfs: remove unnecessary level check in balance_level
In the callchain:

btrfs_search_slot()
   if (level != 0)
      setup_nodes_for_search()
          balance_level()

It is just impossible to have level=0 in balance_level, we can drop the
check.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:30 +02:00
Liu Bo
3cf5068f3d Btrfs: unify error handling of btrfs_lookup_dir_item
Unify the error handling of directory item lookups using IS_ERR_OR_NULL.
No functional changes.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:30 +02:00
Liu Bo
3b2fd80160 Btrfs: use args in the correct order for kcalloc in btrfsic_read_block
kcalloc is defined as:

  kcalloc(size_t n, size_t size, gfp_t flags)

Although this won't cause problems in practice, btrfsic_read_block()
uses kcalloc with n and size in the opposite order.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:30 +02:00
Nikolay Borisov
a27a94c2b0 btrfs: Make btrfs_find_device_by_devspec return btrfs_device directly
Instead of returning an error value and using one of the parameters for
returning the actual object we are interested in just refactor the
function to directly return btrfs_device *. Also bubble up the error
handling for the special BTRFS_ERROR_DEV_MISSING_NOT_FOUND value into
btrfs_rm_device. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:30 +02:00
Nikolay Borisov
6c05040702 btrfs: Make btrfs_find_device_missing_or_by_path return directly a device
This function returns a numeric error value and additionally the
device found in one of its input parameters. Simplify this by making
the function directly return a pointer to btrfs_device. Additionally
adjust the caller to handle the case when we want to remove the
'missing' device and ENOENT is returned to return the expected
positive error value, parsed by progs. Finally, unexport the function
since it's not called outside of volume.c. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:29 +02:00
Nikolay Borisov
b444ad46b2 btrfs: Make btrfs_find_device_by_path return struct btrfs_device
Currently this function returns an error code as well as uses one of
its arguments as a return value for struct btrfs_device. Change the
function so that it returns btrfs_device directly and use the usual
"encode error in pointer" mechanics if something goes wrong. No
functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:29 +02:00
Jeff Mahoney
374b0e2d6b btrfs: fix error handling in free_log_tree
When we hit an I/O error in free_log_tree->walk_log_tree during file system
shutdown we can crash due to there not being a valid transaction handle.

Use btrfs_handle_fs_error when there's no transaction handle to use.

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000060
  IP: free_log_tree+0xd2/0x140 [btrfs]
  PGD 0 P4D 0
  Oops: 0000 [#1] SMP DEBUG_PAGEALLOC PTI
  Modules linked in: <modules>
  CPU: 2 PID: 23544 Comm: umount Tainted: G        W        4.12.14-kvmsmall #9 SLE15 (unreleased)
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014
  task: ffff96bfd3478880 task.stack: ffffa7cf40d78000
  RIP: 0010:free_log_tree+0xd2/0x140 [btrfs]
  RSP: 0018:ffffa7cf40d7bd10 EFLAGS: 00010282
  RAX: 00000000fffffffb RBX: 00000000fffffffb RCX: 0000000000000002
  RDX: 0000000000000000 RSI: ffff96c02f07d4c8 RDI: 0000000000000282
  RBP: ffff96c013cf1000 R08: ffff96c02f07d4c8 R09: ffff96c02f07d4d0
  R10: 0000000000000000 R11: 0000000000000002 R12: 0000000000000000
  R13: ffff96c005e800c0 R14: ffffa7cf40d7bdb8 R15: 0000000000000000
  FS:  00007f17856bcfc0(0000) GS:ffff96c03f600000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000060 CR3: 0000000045ed6002 CR4: 00000000003606e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   ? wait_for_writer+0xb0/0xb0 [btrfs]
   btrfs_free_log+0x17/0x30 [btrfs]
   btrfs_drop_and_free_fs_root+0x9a/0xe0 [btrfs]
   btrfs_free_fs_roots+0xc0/0x130 [btrfs]
   ? wait_for_completion+0xf2/0x100
   close_ctree+0xea/0x2e0 [btrfs]
   ? kthread_stop+0x161/0x260
   generic_shutdown_super+0x6c/0x120
   kill_anon_super+0xe/0x20
   btrfs_kill_super+0x13/0x100 [btrfs]
   deactivate_locked_super+0x3f/0x70
   cleanup_mnt+0x3b/0x70
   task_work_run+0x78/0x90
   exit_to_usermode_loop+0x77/0xa6
   do_syscall_64+0x1c5/0x1e0
   entry_SYSCALL_64_after_hwframe+0x42/0xb7
  RIP: 0033:0x7f1784f90827
  RSP: 002b:00007ffdeeb03118 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
  RAX: 0000000000000000 RBX: 0000556a60c62970 RCX: 00007f1784f90827
  RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000556a60c62b50
  RBP: 0000000000000000 R08: 0000000000000005 R09: 00000000ffffffff
  R10: 0000556a60c63900 R11: 0000000000000246 R12: 0000556a60c62b50
  R13: 00007f17854a81c4 R14: 0000000000000000 R15: 0000000000000000
  RIP: free_log_tree+0xd2/0x140 [btrfs] RSP: ffffa7cf40d7bd10
  CR2: 0000000000000060

Fixes: 681ae50917 ("Btrfs: cleanup reserved space when freeing tree log on error")
CC: <stable@vger.kernel.org> # v3.13
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:29 +02:00
Misono Tomohiro
380fd06640 btrfs: remove redundant variable from btrfs_cross_ref_exist
Since commit d7df2c796d ("Btrfs attach delayed ref updates to delayed
ref heads"), check_delayed_ref() won't return -ENOENT.

In btrfs_cross_ref_exist(), two variables 'ret' and 'ret2' are
originally used to handle -ENOENT error case.  Since the code is not
needed anymore, let's just remove 'ret2'.

Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:29 +02:00
Liu Bo
e49aabd973 Btrfs: set leave_spinning in btrfs_get_extent
Unless it's going to read inline extents from btree leaf to page,
btrfs_get_extent won't sleep during the period of holding path lock.

This sets leave_spinning at first and sets path to blocking mode right
before reading inline extent if that's the case.  The benefit is that a
path in spinning mode typically has lower impact (faster) on waiters
rather than that in the blocking mode.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:29 +02:00
Liu Bo
de2c6615dc Btrfs: fix alignment in declaration and prototype of btrfs_get_extent
This fixes btrfs_get_extent to be consistent with our existing
declaration style.

Note: For the record, indentation styles that are accepted are both,
aligning under the opening ( and tab or double tab indentation on the
next line.  Preferrably not spliting the type or long expressions in the
argument lists.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
[ add note ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:29 +02:00
Colin Ian King
29c5e5d496 btrfs: remove unused pointer 'tree' in btrfs_submit_compressed_read
Pointer 'tree' is being assigned but is never used hence it is redundant
and can be removed. This is a leftover from cleanup patch
00032d38ea ("btrfs: drop extent_io_ops::merge_bio_hook
callback").

Cleans up clang warning:

  warning: variable 'tree' set but not used [-Wunused-but-set-variable]

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:28 +02:00
Colin Ian King
d005dbeca0 btrfs: remove unused pointer inode in relink_file_extents
Pointer inode is being assigned but is never used hence it is redundant
and can be removed. It's been unused since the introduction in
38c227d87c ("Btrfs: snapshot-aware defrag").

Cleans up clang warning:

  variable ‘inode’ set but not used [-Wunused-but-set-variable]

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:28 +02:00
Su Yue
28c4a3e21a btrfs: defrag: use btrfs_mod_outstanding_extents in cluster_pages_for_defrag
Since commit 8b62f87bad ("Btrfs: rework outstanding_extents"),
manual operations of outstanding_extent in btrfs_inode are replaced by
btrfs_mod_outstanding_extents().
The one in cluster_pages_for_defrag seems to be lost, so replace it
of btrfs_mod_outstanding_extents().

Fixes: 8b62f87bad ("Btrfs: rework outstanding_extents")
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:28 +02:00
Liu Bo
6aadd9eb74 Btrfs: remove confusing tracepoint in btrfs_add_reserved_bytes
Here we're not releasing any space, but transferring bytes from
->bytes_may_use to ->bytes_reserved. The last change to the code in
commit 18513091af ("btrfs: update btrfs_space_info's
bytes_may_use timely") removed a conditional tracepoint and the logic
changed too but the tracepiont remained.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:28 +02:00
Liu Bo
c64142807f btrfs: free path at an earlier point in btrfs_get_extent
trace_btrfs_get_extent() has nothing to do with path, place
btrfs_free_path ahead so that we can unlock path on error.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:28 +02:00
Liu Bo
9688e9a99e Btrfs: use next_state in find_first_extent_bit
As next_state() is already defined to get the next state, use it in
find_first_extent_bit. No functional changes.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:28 +02:00
Qu Wenruo
b72c3aba09 btrfs: locking: Add extra check in btrfs_init_new_buffer() to avoid deadlock
[BUG]
For certain crafted image, whose csum root leaf has missing backref, if
we try to trigger write with data csum, it could cause deadlock with the
following kernel WARN_ON():

  WARNING: CPU: 1 PID: 41 at fs/btrfs/locking.c:230 btrfs_tree_lock+0x3e2/0x400
  CPU: 1 PID: 41 Comm: kworker/u4:1 Not tainted 4.18.0-rc1+ #8
  Workqueue: btrfs-endio-write btrfs_endio_write_helper
  RIP: 0010:btrfs_tree_lock+0x3e2/0x400
  Call Trace:
   btrfs_alloc_tree_block+0x39f/0x770
   __btrfs_cow_block+0x285/0x9e0
   btrfs_cow_block+0x191/0x2e0
   btrfs_search_slot+0x492/0x1160
   btrfs_lookup_csum+0xec/0x280
   btrfs_csum_file_blocks+0x2be/0xa60
   add_pending_csums+0xaf/0xf0
   btrfs_finish_ordered_io+0x74b/0xc90
   finish_ordered_fn+0x15/0x20
   normal_work_helper+0xf6/0x500
   btrfs_endio_write_helper+0x12/0x20
   process_one_work+0x302/0x770
   worker_thread+0x81/0x6d0
   kthread+0x180/0x1d0
   ret_from_fork+0x35/0x40

[CAUSE]
That crafted image has missing backref for csum tree root leaf.  And
when we try to allocate new tree block, since there is no
EXTENT/METADATA_ITEM for csum tree root, btrfs consider it's free slot
and use it.

The extent tree of the image looks like:

  Normal image                      |       This fuzzed image
  ----------------------------------+--------------------------------
  BG 29360128                       | BG 29360128
   One empty slot                   |  One empty slot
  29364224: backref to UUID tree    | 29364224: backref to UUID tree
   Two empty slots                  |  Two empty slots
  29376512: backref to CSUM tree    |  One empty slot (bad type) <<<
  29380608: backref to D_RELOC tree | 29380608: backref to D_RELOC tree
  ...                               | ...

Since bytenr 29376512 has no METADATA/EXTENT_ITEM, when btrfs try to
alloc tree block, it's an valid slot for btrfs.

And for finish_ordered_write, when we need to insert csum, we try to CoW
csum tree root.

By accident, empty slots at bytenr BG_OFFSET, BG_OFFSET + 8K,
BG_OFFSET + 12K is already used by tree block COW for other trees, the
next empty slot is BG_OFFSET + 16K, which should be the backref for CSUM
tree.

But due to the bad type, btrfs can recognize it and still consider it as
an empty slot, and will try to use it for csum tree CoW.

Then in the following call trace, we will try to lock the new tree
block, which turns out to be the old csum tree root which is already
locked:

btrfs_search_slot() called on csum tree root, which is at 29376512
|- btrfs_cow_block()
   |- btrfs_set_lock_block()
   |  |- Now locks tree block 29376512 (old csum tree root)
   |- __btrfs_cow_block()
      |- btrfs_alloc_tree_block()
         |- btrfs_reserve_extent()
            | Now it returns tree block 29376512, which extent tree
            | shows its empty slot, but it's already hold by csum tree
            |- btrfs_init_new_buffer()
               |- btrfs_tree_lock()
                  | Triggers WARN_ON(eb->lock_owner == current->pid)
                  |- wait_event()
                     Wait lock owner to release the lock, but it's
                     locked by ourself, so it will deadlock

[FIX]
This patch will do the lock_owner and current->pid check at
btrfs_init_new_buffer().
So above deadlock can be avoided.

Since such problem can only happen in crafted image, we will still
trigger kernel warning for later aborted transaction, but with a little
more meaningful warning message.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=200405
Reported-by: Xu Wen <wen.xu@gatech.edu>
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:27 +02:00
Qu Wenruo
65c6e82bec btrfs: Handle owner mismatch gracefully when walking up tree
[BUG]
When mounting certain crafted image, btrfs will trigger kernel BUG_ON()
when trying to recover balance:

  kernel BUG at fs/btrfs/extent-tree.c:8956!
  invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
  CPU: 1 PID: 662 Comm: mount Not tainted 4.18.0-rc1-custom+ #10
  RIP: 0010:walk_up_proc+0x336/0x480 [btrfs]
  RSP: 0018:ffffb53540c9b890 EFLAGS: 00010202
  Call Trace:
   walk_up_tree+0x172/0x1f0 [btrfs]
   btrfs_drop_snapshot+0x3a4/0x830 [btrfs]
   merge_reloc_roots+0xe1/0x1d0 [btrfs]
   btrfs_recover_relocation+0x3ea/0x420 [btrfs]
   open_ctree+0x1af3/0x1dd0 [btrfs]
   btrfs_mount_root+0x66b/0x740 [btrfs]
   mount_fs+0x3b/0x16a
   vfs_kern_mount.part.9+0x54/0x140
   btrfs_mount+0x16d/0x890 [btrfs]
   mount_fs+0x3b/0x16a
   vfs_kern_mount.part.9+0x54/0x140
   do_mount+0x1fd/0xda0
   ksys_mount+0xba/0xd0
   __x64_sys_mount+0x21/0x30
   do_syscall_64+0x60/0x210
   entry_SYSCALL_64_after_hwframe+0x49/0xbe

[CAUSE]
Extent tree corruption.  In this particular case, reloc tree root's
owner is DATA_RELOC_TREE (should be TREE_RELOC), thus its backref is
corrupted and we failed the owner check in walk_up_tree().

[FIX]
It's pretty hard to take care of every extent tree corruption, but at
least we can remove such BUG_ON() and exit more gracefully.

And since in this particular image, DATA_RELOC_TREE and TREE_RELOC share
the same root (which is obviously invalid), we needs to make
__del_reloc_root() more robust to detect such invalid sharing to avoid
possible NULL dereference as root->node can be NULL in this case.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=200411
Reported-by: Xu Wen <wen.xu@gatech.edu>
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:27 +02:00
zhong jiang
45128b08f7 btrfs: change btrfs_pin_log_trans to return void
btrfs_pin_log_trans defines the variable "ret" for return value, but it
is not modified after initialization. Further, I find that none of the
callers do handles the return value, so it is safe to drop the unneeded
"ret" and make it return void.

Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:27 +02:00
zhong jiang
556f3ca88e btrfs: change btrfs_free_reserved_bytes to return void
btrfs_free_reserved_bytes uses the variable "ret" for return value,
but it is not modified after initialzation. Further, I find that any of
the callers do not handle the return value, so it is safe to drop the
unneeded "ret" and return void. There are no callees that would need the
function to handle or pass the value either.

Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:27 +02:00
Liu Bo
bee6ec822a Btrfs: remove always true if branch in btrfs_get_extent
@path is always NULL when it comes to the if branch.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:27 +02:00
Qu Wenruo
9c7b0c2e8d btrfs: qgroup: Dirty all qgroups before rescan
[BUG]
In the following case, rescan won't zero out the number of qgroup 1/0:

  $ mkfs.btrfs -fq $DEV
  $ mount $DEV /mnt

  $ btrfs quota enable /mnt
  $ btrfs qgroup create 1/0 /mnt
  $ btrfs sub create /mnt/sub
  $ btrfs qgroup assign 0/257 1/0 /mnt

  $ dd if=/dev/urandom of=/mnt/sub/file bs=1k count=1000
  $ btrfs sub snap /mnt/sub /mnt/snap
  $ btrfs quota rescan -w /mnt
  $ btrfs qgroup show -pcre /mnt
  qgroupid         rfer         excl     max_rfer     max_excl parent  child
  --------         ----         ----     --------     -------- ------  -----
  0/5          16.00KiB     16.00KiB         none         none ---     ---
  0/257      1016.00KiB     16.00KiB         none         none 1/0     ---
  0/258      1016.00KiB     16.00KiB         none         none ---     ---
  1/0        1016.00KiB     16.00KiB         none         none ---     0/257

So far so good, but:

  $ btrfs qgroup remove 0/257 1/0 /mnt
  WARNING: quotas may be inconsistent, rescan needed
  $ btrfs quota rescan -w /mnt
  $ btrfs qgroup show -pcre  /mnt
  qgoupid         rfer         excl     max_rfer     max_excl parent  child
  --------         ----         ----     --------     -------- ------  -----
  0/5          16.00KiB     16.00KiB         none         none ---     ---
  0/257      1016.00KiB     16.00KiB         none         none ---     ---
  0/258      1016.00KiB     16.00KiB         none         none ---     ---
  1/0        1016.00KiB     16.00KiB         none         none ---     ---
	     ^^^^^^^^^^     ^^^^^^^^ not cleared

[CAUSE]
Before rescan we call qgroup_rescan_zero_tracking() to zero out all
qgroups' accounting numbers.

However we don't mark all qgroups dirty, but rely on rescan to do so.

If we have any high level qgroup without children, it won't be marked
dirty during rescan, since we cannot reach that qgroup.

This will cause QGROUP_INFO items of childless qgroups never get updated
in the quota tree, thus their numbers will stay the same in "btrfs
qgroup show" output.

[FIX]
Just mark all qgroups dirty in qgroup_rescan_zero_tracking(), so even if
we have childless qgroups, their QGROUP_INFO items will still get
updated during rescan.

Reported-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Tested-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:26 +02:00
Omar Sandoval
3293428096 Btrfs: clean up scrub is_dev_replace parameter
struct scrub_ctx has an ->is_dev_replace member, so there's no point in
passing around is_dev_replace where sctx is available.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:26 +02:00
Anand Jain
1da739678e btrfs: add helper to obtain number of devices with ongoing dev-replace
When the replace is running the fs_devices::num_devices also includes
the replaced device, however in some operations like device delete and
balance it needs the actual num_devices without the repalced devices.
The function btrfs_num_devices() just provides that.

And here is a scenario how balance and repalce items could co-exist:

Consider balance is started and paused, now start the replace followed
by a unmount or system power-cycle. During following mount, the
open_ctree() first restarts the balance so it must check for the device
replace otherwise our num_devices calculation will be wrong.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:26 +02:00
Anand Jain
16220c467a btrfs: add assertions where number of devices could go below 0
In preparation to add helper function to deduce the num_devices with
replace running, use assert instead of BUG_ON or WARN_ON. The number of
devices would not normally drop to 0 due to other checks so the assert
is sufficient.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog, adjust the assert condition ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:26 +02:00
zhong jiang
f8b00e0f06 btrfs: remove unneeded NULL checks before kfree
Kfree has taken the NULL pointer into account. So remove the check
before kfree.

The issue is detected with the help of Coccinelle.

Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:26 +02:00
Liu Bo
4b6f8e9695 Btrfs: do not unnecessarily pass write_lock_level when processing leaf
As we're going to return right after the call, it's not necessary to get
update the new write_lock_level from unlock_up.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:26 +02:00
Misono Tomohiro
4fd786e6c3 btrfs: Remove 'objectid' member from struct btrfs_root
There are two members in struct btrfs_root which indicate root's
objectid: objectid and root_key.objectid.

They are both set to the same value in __setup_root():

  static void __setup_root(struct btrfs_root *root,
                           struct btrfs_fs_info *fs_info,
                           u64 objectid)
  {
    ...
    root->objectid = objectid;
    ...
    root->root_key.objectid = objecitd;
    ...
  }

and not changed to other value after initialization.

grep in btrfs directory shows both are used in many places:
  $ grep -rI "root->root_key.objectid" | wc -l
  133
  $ grep -rI "root->objectid" | wc -l
  55
 (4.17, inc. some noise)

It is confusing to have two similar variable names and it seems
that there is no rule about which should be used in a certain case.

Since ->root_key itself is needed for tree reloc tree, let's remove
'objecitd' member and unify code to use ->root_key.objectid in all places.

Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:25 +02:00
Lu Fengqi
5a2cb25ab9 btrfs: remove a useless return statement in btrfs_block_rsv_add
Since ret must be 0 here, don't have to return.  No functional change
and code readability is not hurt.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:25 +02:00
Lu Fengqi
684572df94 btrfs: Remove root parameter from btrfs_insert_dir_item
All callers pass the root tree of dir, we can push that down to the
function itself.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:25 +02:00
Lu Fengqi
3a58417486 btrfs: switch update_size to bool in btrfs_block_rsv_migrate and btrfs_rsv_add_bytes
Using true and false here is closer to the expected semantic than using
0 and 1.  No functional change.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:25 +02:00
Lu Fengqi
a7176f74fa btrfs: simplify the send_in_progress check in btrfs_delete_subvolume
Only when send_in_progress, we have to do something different such as
btrfs_warn() and return -EPERM. Therefore, we could check
send_in_progress first and process error handling, after the
root_item_lock has been got.

Just for better readability. No functional change.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15 17:23:25 +02:00
Al Viro
3837d208d8 simplify btrfs_lookup()
d_splice_alias() is fine with ERR_PTR(-E...) for inode

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-10-10 16:38:27 -04:00
Matthew Wilcox
3159f943aa xarray: Replace exceptional entries
Introduce xarray value entries and tagged pointers to replace radix
tree exceptional entries.  This is a slight change in encoding to allow
the use of an extra bit (we can now store BITS_PER_LONG - 1 bits in a
value entry).  It is also a change in emphasis; exceptional entries are
intimidating and different.  As the comment explains, you can choose
to store values or pointers in the xarray and they are both first-class
citizens.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Josef Bacik <jbacik@fb.com>
2018-09-29 22:47:49 -04:00
Linus Torvalds
5404525b98 for-4.19-rc2-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAluRLa8ACgkQxWXV+ddt
 WDvc+BAAqxTMVngZ60WfktXzsS56OB6fu/R3DORgYcSZ0BCD4zTwoDlCjLhrCK6E
 cmC+BMj+AspDQYiYESwGyFcN10sK0X7w7fa3wypTc4GNWxpkRm0Z6zT/kCvLUhdI
 NlkMqAfsZ9N6iIXcR0qOxI7G55e3mpXPZGdFTk5rmDTv/9TqU0TMp9s8Zw5scn6R
 ctdE+iE0lpRfNjF8ZDH1BtYIV4g2X81sZF/fkGz621HQfMTCjjPHFdlz+jlirBaf
 BrYR4w4zjVuMKd3ZC5FHffVchbkvt29h6fAr4sEpJTwFJwd8pjI7GuPYWDQ918NB
 TGX6EUP6usQqDK2zD405jCS6MbMshJm3uh5kmEpeNgK/tKJTln8Sbef/Xs93yIn2
 +k9BMKOIcUHHBiv6PgCaZomcWCpii2S2u6vncqCnNuI4wK1RN3gHJc5YPhJArlrB
 NUFJiTCQE6LWYOP2Hw+rggcrtBxli0bX7Mqp5FYFVdh5KBvolJE1o3B/JS8qpqRF
 u0dPwbLHtTpTpXM5EfmM8a45S+DxuxTDBh3vdoAOM9LN/ivpeqqnFbHrIGmrTMjo
 pQJ8aTrCwYMEMNu6oCV1cniFrOYRZ439hYjg524MjVXYCRyxhzAdVmVTEBaLjWCW
 9GlGqEC7YZY2wLi5lPEGqxsIaVVELpettJB9KbBKmYB47VFWEf0=
 =fu93
 -----END PGP SIGNATURE-----

Merge tag 'for-4.19-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:

 - fix for improper fsync after hardlink

 - fix for a corruption during file deduplication

 - use after free fixes

 - RCU warning fix

 - fix for buffered write to nodatacow file

* tag 'for-4.19-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: Fix suspicious RCU usage warning in btrfs_debug_in_rcu
  btrfs: use after free in btrfs_quota_enable
  btrfs: btrfs_shrink_device should call commit transaction at the end
  btrfs: fix qgroup_free wrong num_bytes in btrfs_subvolume_reserve_metadata
  Btrfs: fix data corruption when deduplicating between different files
  Btrfs: sync log after logging new name
  Btrfs: fix unexpected failure of nocow buffered writes after snapshotting when low on space
2018-09-06 09:04:45 -07:00
Misono Tomohiro
b6fdfbff07 btrfs: Fix suspicious RCU usage warning in btrfs_debug_in_rcu
Commit 672d599041 ("btrfs: Use wrapper macro for rcu string to remove
duplicate code") replaces some open coded RCU string handling with macro.

It turns out that btrfs_debug_in_rcu() is used for the first time and
the macro lacks lock/unlock of RCU string for non-debug case (i.e. when
the message is not printed), leading to suspicious RCU usage warning
when CONFIG_PROVE_RCU is on.

Fix this by adding a wrapper to call lock/unlock for the non-debug case
too.

Fixes: 672d599041 ("btrfs: Use wrapper macro for rcu string to remove duplicate code")
Reported-by: David Howells <dhowells@redhat.com>
Tested-by: David Howells <dhowells@redhat.com>
Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-24 14:09:43 +02:00
Dan Carpenter
b9b8a41ade btrfs: use after free in btrfs_quota_enable
The issue here is that btrfs_commit_transaction() frees "trans" on both
the error and the success path.  So the problem would be if
btrfs_commit_transaction() succeeds, and then qgroup_rescan_init()
fails.  That means that "ret" is non-zero and "trans" is non-NULL and it
leads to a use after free inside the btrfs_end_transaction() macro.

Fixes: 340f1aa27f ("btrfs: qgroups: Move transaction management inside btrfs_quota_enable/disable")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-23 17:37:27 +02:00
Anand Jain
801660b040 btrfs: btrfs_shrink_device should call commit transaction at the end
Test case btrfs/164 reports use-after-free:

[ 6712.084324] general protection fault: 0000 [#1] PREEMPT SMP
..
[ 6712.195423]  btrfs_update_commit_device_size+0x75/0xf0 [btrfs]
[ 6712.201424]  btrfs_commit_transaction+0x57d/0xa90 [btrfs]
[ 6712.206999]  btrfs_rm_device+0x627/0x850 [btrfs]
[ 6712.211800]  btrfs_ioctl+0x2b03/0x3120 [btrfs]

Reason for this is that btrfs_shrink_device adds the resized device to
the fs_devices::resized_devices after it has called the last commit
transaction.

So the list fs_devices::resized_devices is not empty when
btrfs_shrink_device returns.  Now the parent function
btrfs_rm_device calls:

        btrfs_close_bdev(device);
        call_rcu(&device->rcu, free_device_rcu);

and then does the transactio ncommit. It goes through the
fs_devices::resized_devices in btrfs_update_commit_device_size and
leads to use-after-free.

Fix this by making sure btrfs_shrink_device calls the last needed
btrfs_commit_transaction before the return. This is consistent with what
the grow counterpart does and this makes sure the on-disk state is
persistent when the function returns.

Reported-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Tested-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-23 17:37:27 +02:00
Lu Fengqi
a5b7f4295e btrfs: fix qgroup_free wrong num_bytes in btrfs_subvolume_reserve_metadata
After btrfs_qgroup_reserve_meta_prealloc(), num_bytes will be assigned
again by btrfs_calc_trans_metadata_size(). Once block_rsv fails, we
can't properly free the num_bytes of the previous qgroup_reserve. Use a
separate variable to store the num_bytes of the qgroup_reserve.

Delete the comment for the qgroup_reserved that does not exist and add a
comment about use_global_rsv.

Fixes: c4c129db5d ("btrfs: drop unused parameter qgroup_reserved")
CC: stable@vger.kernel.org # 4.18+
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-23 17:37:26 +02:00
Filipe Manana
de02b9f6bb Btrfs: fix data corruption when deduplicating between different files
If we deduplicate extents between two different files we can end up
corrupting data if the source range ends at the size of the source file,
the source file's size is not aligned to the filesystem's block size
and the destination range does not go past the size of the destination
file size.

Example:

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt

  $ xfs_io -f -c "pwrite -S 0x6b 0 2518890" /mnt/foo
  # The first byte with a value of 0xae starts at an offset (2518890)
  # which is not a multiple of the sector size.
  $ xfs_io -c "pwrite -S 0xae 2518890 102398" /mnt/foo

  # Confirm the file content is full of bytes with values 0x6b and 0xae.
  $ od -t x1 /mnt/foo
  0000000 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
  *
  11467540 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b ae ae ae ae ae ae
  11467560 ae ae ae ae ae ae ae ae ae ae ae ae ae ae ae ae
  *
  11777540 ae ae ae ae ae ae ae ae
  11777550

  # Create a second file with a length not aligned to the sector size,
  # whose bytes all have the value 0x6b, so that its extent(s) can be
  # deduplicated with the first file.
  $ xfs_io -f -c "pwrite -S 0x6b 0 557771" /mnt/bar

  # Now deduplicate the entire second file into a range of the first file
  # that also has all bytes with the value 0x6b. The destination range's
  # end offset must not be aligned to the sector size and must be less
  # then the offset of the first byte with the value 0xae (byte at offset
  # 2518890).
  $ xfs_io -c "dedupe /mnt/bar 0 1957888 557771" /mnt/foo

  # The bytes in the range starting at offset 2515659 (end of the
  # deduplication range) and ending at offset 2519040 (start offset
  # rounded up to the block size) must all have the value 0xae (and not
  # replaced with 0x00 values). In other words, we should have exactly
  # the same data we had before we asked for deduplication.
  $ od -t x1 /mnt/foo
  0000000 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
  *
  11467540 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b ae ae ae ae ae ae
  11467560 ae ae ae ae ae ae ae ae ae ae ae ae ae ae ae ae
  *
  11777540 ae ae ae ae ae ae ae ae
  11777550

  # Unmount the filesystem and mount it again. This guarantees any file
  # data in the page cache is dropped.
  $ umount /dev/sdb
  $ mount /dev/sdb /mnt

  $ od -t x1 /mnt/foo
  0000000 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
  *
  11461300 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 00 00 00 00 00
  11461320 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  *
  11470000 ae ae ae ae ae ae ae ae ae ae ae ae ae ae ae ae
  *
  11777540 ae ae ae ae ae ae ae ae
  11777550

  # The bytes in range 2515659 to 2519040 have a value of 0x00 and not a
  # value of 0xae, data corruption happened due to the deduplication
  # operation.

So fix this by rounding down, to the sector size, the length used for the
deduplication when the following conditions are met:

  1) Source file's range ends at its i_size;
  2) Source file's i_size is not aligned to the sector size;
  3) Destination range does not cross the i_size of the destination file.

Fixes: e1d227a42e ("btrfs: Handle unaligned length in extent_same")
CC: stable@vger.kernel.org # 4.2+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-23 17:37:26 +02:00
Filipe Manana
d4682ba03e Btrfs: sync log after logging new name
When we add a new name for an inode which was logged in the current
transaction, we update the inode in the log so that its new name and
ancestors are added to the log. However when we do this we do not persist
the log, so the changes remain in memory only, and as a consequence, any
ancestors that were created in the current transaction are updated such
that future calls to btrfs_inode_in_log() return true. This leads to a
subsequent fsync against such new ancestor directories returning
immediately, without persisting the log, therefore after a power failure
the new ancestor directories do not exist, despite fsync being called
against them explicitly.

Example:

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt

  $ mkdir /mnt/A
  $ mkdir /mnt/B
  $ mkdir /mnt/A/C
  $ touch /mnt/B/foo
  $ xfs_io -c "fsync" /mnt/B/foo
  $ ln /mnt/B/foo /mnt/A/C/foo
  $ xfs_io -c "fsync" /mnt/A
  <power failure>

After the power failure, directory "A" does not exist, despite the explicit
fsync on it.

Instead of fixing this by changing the behaviour of the explicit fsync on
directory "A" to persist the log instead of doing nothing, make the logging
of the new file name (which happens when creating a hard link or renaming)
persist the log. This approach not only is simpler, not requiring addition
of new fields to the inode in memory structure, but also gives us the same
behaviour as ext4, xfs and f2fs (possibly other filesystems too).

A test case for fstests follows soon.

Fixes: 12fcfd22fe ("Btrfs: tree logging unlink/rename fixes")
Reported-by: Vijay Chidambaram <vvijay03@gmail.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-23 17:37:26 +02:00
Linus Torvalds
d9a185f8b4 overlayfs update for 4.19
This contains two new features:
 
  1) Stack file operations: this allows removal of several hacks from the
     VFS, proper interaction of read-only open files with copy-up,
     possibility to implement fs modifying ioctls properly, and others.
 
  2) Metadata only copy-up: when file is on lower layer and only metadata is
     modified (except size) then only copy up the metadata and continue to
     use the data from the lower file.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQSQHSd0lITzzeNWNm3h3BK/laaZPAUCW3srhAAKCRDh3BK/laaZ
 PC6tAQCP+KklcN+TvNp502f+O/kATahSpgnun4NY1/p4I8JV+AEAzdlkTN3+MiAO
 fn9brN6mBK7h59DO3hqedPLJy2vrgwg=
 =QDXH
 -----END PGP SIGNATURE-----

Merge tag 'ovl-update-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs

Pull overlayfs updates from Miklos Szeredi:
 "This contains two new features:

   - Stack file operations: this allows removal of several hacks from
     the VFS, proper interaction of read-only open files with copy-up,
     possibility to implement fs modifying ioctls properly, and others.

   - Metadata only copy-up: when file is on lower layer and only
     metadata is modified (except size) then only copy up the metadata
     and continue to use the data from the lower file"

* tag 'ovl-update-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: (66 commits)
  ovl: Enable metadata only feature
  ovl: Do not do metacopy only for ioctl modifying file attr
  ovl: Do not do metadata only copy-up for truncate operation
  ovl: add helper to force data copy-up
  ovl: Check redirect on index as well
  ovl: Set redirect on upper inode when it is linked
  ovl: Set redirect on metacopy files upon rename
  ovl: Do not set dentry type ORIGIN for broken hardlinks
  ovl: Add an inode flag OVL_CONST_INO
  ovl: Treat metacopy dentries as type OVL_PATH_MERGE
  ovl: Check redirects for metacopy files
  ovl: Move some dir related ovl_lookup_single() code in else block
  ovl: Do not expose metacopy only dentry from d_real()
  ovl: Open file with data except for the case of fsync
  ovl: Add helper ovl_inode_realdata()
  ovl: Store lower data inode in ovl_inode
  ovl: Fix ovl_getattr() to get number of blocks from lower
  ovl: Add helper ovl_dentry_lowerdata() to get lower data dentry
  ovl: Copy up meta inode data from lowest data inode
  ovl: Modify ovl_lookup() and friends to lookup metacopy dentry
  ...
2018-08-21 18:19:09 -07:00
Jens Axboe
5e9d398240 btrfs: readpages() should submit IO as read-ahead
a_ops->readpages() is only ever used for read-ahead.  Ensure that we
pass this information down to the block layer.

Link: http://lkml.kernel.org/r/20180621010725.17813-4-axboe@kernel.dk
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Chris Mason <clm@fb.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-17 16:20:29 -07:00
Robbie Ko
8ecebf4d76 Btrfs: fix unexpected failure of nocow buffered writes after snapshotting when low on space
Commit e9894fd3e3 ("Btrfs: fix snapshot vs nocow writting") forced
nocow writes to fallback to COW, during writeback, when a snapshot is
created. This resulted in writes made before creating the snapshot to
unexpectedly fail with ENOSPC during writeback when success (0) was
returned to user space through the write system call.

The steps leading to this problem are:

1. When it's not possible to allocate data space for a write, the
   buffered write path checks if a NOCOW write is possible.  If it is,
   it will not reserve space and success (0) is returned to user space.

2. Then when a snapshot is created, the root's will_be_snapshotted
   atomic is incremented and writeback is triggered for all inode's that
   belong to the root being snapshotted. Incrementing that atomic forces
   all previous writes to fallback to COW during writeback (running
   delalloc).

3. This results in the writeback for the inodes to fail and therefore
   setting the ENOSPC error in their mappings, so that a subsequent
   fsync on them will report the error to user space. So it's not a
   completely silent data loss (since fsync will report ENOSPC) but it's
   a very unexpected and undesirable behaviour, because if a clean
   shutdown/unmount of the filesystem happens without previous calls to
   fsync, it is expected to have the data present in the files after
   mounting the filesystem again.

So fix this by adding a new atomic named snapshot_force_cow to the
root structure which prevents this behaviour and works the following way:

1. It is incremented when we start to create a snapshot after triggering
   writeback and before waiting for writeback to finish.

2. This new atomic is now what is used by writeback (running delalloc)
   to decide whether we need to fallback to COW or not. Because we
   incremented this new atomic after triggering writeback in the
   snapshot creation ioctl, we ensure that all buffered writes that
   happened before snapshot creation will succeed and not fallback to
   COW (which would make them fail with ENOSPC).

3. The existing atomic, will_be_snapshotted, is kept because it is used
   to force new buffered writes, that start after we started
   snapshotting, to reserve data space even when NOCOW is possible.
   This makes these writes fail early with ENOSPC when there's no
   available space to allocate, preventing the unexpected behaviour of
   writeback later failing with ENOSPC due to a fallback to COW mode.

Fixes: e9894fd3e3 ("Btrfs: fix snapshot vs nocow writting")
Signed-off-by: Robbie Ko <robbieko@synology.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-17 18:35:43 +02:00
Linus Torvalds
a1a4f841ec for-4.19-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAltxe7QACgkQxWXV+ddt
 WDswMA//QlRO+Ln5CH+RlT4fyf1RQUQZblWss2zxrmlo1GRI3Ljf2DNsBE3rD7P4
 NSiXfHmgkdjcQP6poPLJwHxwkNd4NFXglYg64wWO10RjHGhKglmH6ztU88wsPfr2
 2RZv271/NvYIEkEi6kdyy8ilKeWMshOfyj3+PaeapQn67uJfimyiUvDgUgbvwH3c
 yj0nVRLP1C7snNj4Atti/rjXMhG+m1UWfjRkZsmqlBp52k2UAcrtiwQK+DS5b9mL
 aWLSaGmIcJtSMkNJPQBST9GTWbJfKTpceoCzkT0o3irvQpN2e2flAJ4ireL8q4mN
 MvqJ7giPBFHNDcHEzN6VERvsaA1Rx9Vq20ieQl8JAMd4p/bi5ehN3ww+9vau5zCw
 Pc8WeKEILKrLYEAgHOnUO1wxHw994Iv5CA26roTQ0HNXQJjyEZ4m40Ch6LzmfKPm
 WKcHX14Uw22GKaFEXHTOpRZ0U0d1cMTcn5zaAajGsB9LwcaiLM+OiFSPtDkwUOB9
 QGJHklZVXAD1IH9HFPuq85uUtXTLXbxsw1g8phEJGbmaVxxCOAUAXwEk3qxuZNbz
 CHL3G5+l3JEXxfoJSbDW60kr8xic7teqQDszqqP2qlqtP15ty2xc9d5Q8MZajSTZ
 H1z9+0gfjYYHrGuAp69MtCbdQhhDSqLyivjJJm0HBaKfVNGW2Xg=
 =jBaz
 -----END PGP SIGNATURE-----

Merge tag 'for-4.19-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs updates from David Sterba:
 "Mostly fixes and cleanups, nothing big, though the notable thing is
  the inserted/deleted lines delta -1124.

  User visible changes:
   - allow defrag on opened read-only files that have rw permissions;
     similar to what dedupe will allow on such files

  Core changes:
   - tree checker improvements, reported by fuzzing:
      * more checks for: block group items, essential trees
      * chunk type validation
      * mount time cross-checks that physical and logical chunks match
      * switch more error codes to EUCLEAN aka EFSCORRUPTED

  Fixes:
   - fsync corner case fixes

   - fix send failure when root has deleted files still open

   - send, fix incorrect file layout after hole punching beyond eof

   - fix races between mount and deice scan ioctl, found by fuzzing

   - fix deadlock when delayed iput is called from writeback on the same
     inode; rare but has been observed in practice, also removes code

   - fix pinned byte accounting, using the right percpu helpers; this
     should avoid some write IO inefficiency during low space conditions

   - don't remove block group that still has pinned bytes

   - reset on-disk device stats value after replace, otherwise this
     would report stale values for the new device

  Cleanups:
   - time64_t/timespec64 cleanups

   - remove remaining dead code in scrub handling NOCOW extents after
     disabling it in previous cycle

   - simplify fsync regarding ordered extents logic and remove all the
     related code

   - remove redundant arguments in order to reduce stack space
     consumption

   - remove support for V0 type of extents, not in use since 2.6.30

   - remove several unused structure members

   - fewer indirect function calls by inlining some callbacks

   - qgroup rescan timing fixes

   - vfs: iget cleanups"

* tag 'for-4.19-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (182 commits)
  btrfs: revert fs_devices state on error of btrfs_init_new_device
  btrfs: Exit gracefully when chunk map cannot be inserted to the tree
  btrfs: Introduce mount time chunk <-> dev extent mapping check
  btrfs: Verify that every chunk has corresponding block group at mount time
  btrfs: Check that each block group has corresponding chunk at mount time
  Btrfs: send, fix incorrect file layout after hole punching beyond eof
  btrfs: Use wrapper macro for rcu string to remove duplicate code
  btrfs: simplify btrfs_iget
  btrfs: lift make_bad_inode into btrfs_iget
  btrfs: simplify IS_ERR/PTR_ERR checks
  btrfs: btrfs_iget never returns an is_bad_inode inode
  btrfs: replace: Reset on-disk dev stats value after replace
  btrfs: extent-tree: Remove unused __btrfs_free_block_rsv
  btrfs: backref: Use ERR_CAST to return error code
  btrfs: Remove redundant btrfs_release_path from btrfs_unlink_subvol
  btrfs: Remove root parameter from btrfs_unlink_subvol
  btrfs: Remove fs_info from btrfs_add_root_ref
  btrfs: Remove fs_info from btrfs_del_root_ref
  btrfs: Remove fs_info from btrfs_del_root
  btrfs: Remove fs_info from btrfs_delete_delayed_dir_index
  ...
2018-08-13 21:58:53 -07:00
Linus Torvalds
0ea97a2d61 Merge branch 'work.mkdir' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs icache updates from Al Viro:

 - NFS mkdir/open_by_handle race fix

 - analogous solution for FUSE, replacing the one currently in mainline

 - new primitive to be used when discarding halfway set up inodes on
   failed object creation; gives sane warranties re icache lookups not
   returning such doomed by still not freed inodes. A bunch of
   filesystems switched to that animal.

 - Miklos' fix for last cycle regression in iget5_locked(); -stable will
   need a slightly different variant, unfortunately.

 - misc bits and pieces around things icache-related (in adfs and jfs).

* 'work.mkdir' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  jfs: don't bother with make_bad_inode() in ialloc()
  adfs: don't put inodes into icache
  new helper: inode_fake_hash()
  vfs: don't evict uninitialized inode
  jfs: switch to discard_new_inode()
  ext2: make sure that partially set up inodes won't be returned by ext2_iget()
  udf: switch to discard_new_inode()
  ufs: switch to discard_new_inode()
  btrfs: switch to discard_new_inode()
  new primitive: discard_new_inode()
  kill d_instantiate_no_diralias()
  nfs_instantiate(): prevent multiple aliases for directory inode
2018-08-13 20:25:58 -07:00
Naohiro Aota
39379faaad btrfs: revert fs_devices state on error of btrfs_init_new_device
When btrfs hits error after modifying fs_devices in
btrfs_init_new_device() (such as btrfs_add_dev_item() returns error), it
leaves everything as is, but frees allocated btrfs_device. As a result,
fs_devices->devices and fs_devices->alloc_list contain already freed
btrfs_device, leading to later use-after-free bug.

Error path also messes the things like ->num_devices. While they go back
to the original value by unscanning btrfs devices, it is safe to revert
them here.

Fixes: 79787eaab4 ("btrfs: replace many BUG_ONs with proper error handling")
Signed-off-by: Naohiro Aota <naota@elisp.net>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:04 +02:00
Qu Wenruo
64f64f43c8 btrfs: Exit gracefully when chunk map cannot be inserted to the tree
It's entirely possible that a crafted btrfs image contains overlapping
chunks.

Although we can't detect such problem by tree-checker, it's not a
catastrophic problem, current extent map can already detect such problem
and return -EEXIST.

We just only need to exit gracefully and fail the mount.

Reported-by: Xu Wen <wen.xu@gatech.edu>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=200409
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:03 +02:00
Qu Wenruo
cf90d884b3 btrfs: Introduce mount time chunk <-> dev extent mapping check
This patch will introduce chunk <-> dev extent mapping check, to protect
us against invalid dev extents or chunks.

Since chunk mapping is the fundamental infrastructure of btrfs, extra
check at mount time could prevent a lot of unexpected behavior (BUG_ON).

Reported-by: Xu Wen <wen.xu@gatech.edu>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=200403
Link: https://bugzilla.kernel.org/show_bug.cgi?id=200407
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:03 +02:00
Qu Wenruo
7ef49515fa btrfs: Verify that every chunk has corresponding block group at mount time
If a crafted image has missing block group items, it could cause
unexpected behavior and breaks the assumption of 1:1 chunk<->block group
mapping.

Although we have the block group -> chunk mapping check, we still need
chunk -> block group mapping check.

This patch will do extra check to ensure each chunk has its
corresponding block group.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=199847
Reported-by: Xu Wen <wen.xu@gatech.edu>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:03 +02:00
Qu Wenruo
514c7dca85 btrfs: Check that each block group has corresponding chunk at mount time
A crafted btrfs image with incorrect chunk<->block group mapping will
trigger a lot of unexpected things as the mapping is essential.

Although the problem can be caught by block group item checker
added in "btrfs: tree-checker: Verify block_group_item", it's still not
sufficient.  A sufficiently valid block group item can pass the check
added by the mentioned patch but could fail to match the existing chunk.

This patch will add extra block group -> chunk mapping check, to ensure
we have a completely matching (start, len, flags) chunk for each block
group at mount time.

Here we reuse the original helper find_first_block_group(), which is
already doing the basic bg -> chunk checks, adding further checks of the
start/len and type flags.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=199837
Reported-by: Xu Wen <wen.xu@gatech.edu>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:03 +02:00
Filipe Manana
22d3151c2c Btrfs: send, fix incorrect file layout after hole punching beyond eof
When doing an incremental send, if we have a file in the parent snapshot
that has prealloc extents beyond EOF and in the send snapshot it got a
hole punch that partially covers the prealloc extents, the send stream,
when replayed by a receiver, can result in a file that has a size bigger
than it should and filled with zeroes past the correct EOF.

For example:

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt

  $ xfs_io -f -c "falloc -k 0 4M" /mnt/foobar
  $ xfs_io -c "pwrite -S 0xea 0 1M" /mnt/foobar

  $ btrfs subvolume snapshot -r /mnt /mnt/snap1
  $ btrfs send -f /tmp/1.send /mnt/snap1

  $ xfs_io -c "fpunch 1M 2M" /mnt/foobar

  $ btrfs subvolume snapshot -r /mnt /mnt/snap2
  $ btrfs send -f /tmp/2.send -p /mnt/snap1 /mnt/snap2

  $ stat --format %s /mnt/snap2/foobar
  1048576
  $ md5sum /mnt/snap2/foobar
  d31659e82e87798acd4669a1e0a19d4f  /mnt/snap2/foobar

  $ umount /mnt
  $ mkfs.btrfs -f /dev/sdc
  $ mount /dev/sdc /mnt

  $ btrfs receive -f /mnt/1.snap /mnt
  $ btrfs receive -f /mnt/2.snap /mnt

  $ stat --format %s /mnt/snap2/foobar
  3145728
  # --> should be 1Mb and not 3Mb (which was the end offset of hole
  #     punch operation)
  $ md5sum /mnt/snap2/foobar
  117baf295297c2a995f92da725b0b651  /mnt/snap2/foobar
  # --> should be d31659e82e87798acd4669a1e0a19d4f as in the original fs

This issue actually happens only since commit ffa7c4296e ("Btrfs: send,
do not issue unnecessary truncate operations"), but before that commit we
were issuing a write operation full of zeroes (to "punch" a hole) which
was extending the file size beyond the correct value and then immediately
issue a truncate operation to the correct size and undoing the previous
write operation. Since the send protocol does not support fallocate, for
extent preallocation and hole punching, fix this by not even attempting
to send a "hole" (regular write full of zeroes) if it starts at an offset
greater then or equals to the file's size. This approach, besides being
much more simple then making send issue the truncate operation, adds the
benefit of avoiding the useless pair of write of zeroes and truncate
operations, saving time and IO at the receiver and reducing the size of
the send stream.

A test case for fstests follows soon.

Fixes: ffa7c4296e ("Btrfs: send, do not issue unnecessary truncate operations")
CC: stable@vger.kernel.org # 4.17+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:03 +02:00
Misono Tomohiro
672d599041 btrfs: Use wrapper macro for rcu string to remove duplicate code
Cleanup patch and no functional changes.

Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:02 +02:00
Al Viro
f5b3a4173f btrfs: simplify btrfs_iget
Don't open-code iget_failed(), don't bother with btrfs_free_path(NULL),
move handling of positive return values of btrfs_lookup_inode() from
btrfs_read_locked_inode() to btrfs_iget() and kill now obviously
pointless ASSERT() in there.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:02 +02:00
Al Viro
9bc2ceff66 btrfs: lift make_bad_inode into btrfs_iget
We don't need to check is_bad_inode() after the call of
btrfs_read_locked_inode() - it's exactly the same as checking return
value for being non-zero.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: David Sterba <dsterba@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:02 +02:00
Al Viro
8d9e220ca0 btrfs: simplify IS_ERR/PTR_ERR checks
IS_ERR(p) && PTR_ERR(p) == n is a weird way to spell p == ERR_PTR(n).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: David Sterba <dsterba@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:02 +02:00
Al Viro
2e19f1f9d3 btrfs: btrfs_iget never returns an is_bad_inode inode
Just get rid of pointless checks.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:02 +02:00
Misono Tomohiro
1e7e1f9e3a btrfs: replace: Reset on-disk dev stats value after replace
on-disk devs stats value is updated in btrfs_run_dev_stats(),
which is called during commit transaction, if device->dev_stats_ccnt
is not zero.

Since current replace operation does not touch dev_stats_ccnt,
on-disk dev stats value is not updated. Therefore "btrfs device stats"
may return old device's value after umount/mount
(Example: See "btrfs ins dump-t -t DEV $DEV" after btrfs/100 finish).

Fix this by just incrementing dev_stats_ccnt in
btrfs_dev_replace_finishing() when replace is succeeded and this will
update the values.

Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:01 +02:00
Misono Tomohiro
85c3954819 btrfs: extent-tree: Remove unused __btrfs_free_block_rsv
There is no user of this function anymore.

This was forgotten to be removed in commit a575ceeb13
("Btrfs: get rid of unused orphan infrastructure").

Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:01 +02:00
Misono Tomohiro
afc6961ffd btrfs: backref: Use ERR_CAST to return error code
Use ERR_CAST() instead of void * to make meaning clear.

Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:01 +02:00
Lu Fengqi
5b7d687ad5 btrfs: Remove redundant btrfs_release_path from btrfs_unlink_subvol
Although it is safe to call this on already released paths with no locks
held or extent buffers, removing the redundant btrfs_release_path is
reasonable.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:01 +02:00
Lu Fengqi
401b3b19d5 btrfs: Remove root parameter from btrfs_unlink_subvol
All callers pass the root tree of dir, we can push that down to the
function itself.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:01 +02:00
Lu Fengqi
6025c19fb2 btrfs: Remove fs_info from btrfs_add_root_ref
It can be referenced from the passed transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:00 +02:00
Lu Fengqi
3ee1c5530e btrfs: Remove fs_info from btrfs_del_root_ref
It can be referenced from the passed transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:00 +02:00
Lu Fengqi
ab9ce7d42b btrfs: Remove fs_info from btrfs_del_root
It can be referenced from the passed transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:00 +02:00
Lu Fengqi
9add29457a btrfs: Remove fs_info from btrfs_delete_delayed_dir_index
It can be referenced from the passed transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:00 +02:00
Lu Fengqi
4465c8b422 btrfs: Remove fs_info from btrfs_insert_delayed_dir_index
It can be referenced from the passed transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:13:00 +02:00
David Sterba
b5851021f1 btrfs: extent-tree: remove unused member walk_control::for_reloc
Leftover after fix e339a6b097 ("Btrfs: __btrfs_mod_ref should always
use no_quota"), that removed it from the function calls but not the
structure.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:59 +02:00
Filipe Manana
46b2f4590a Btrfs: fix send failure when root has deleted files still open
The more common use case of send involves creating a RO snapshot and then
use it for a send operation. In this case it's not possible to have inodes
in the snapshot that have a link count of zero (inode with an orphan item)
since during snapshot creation we do the orphan cleanup. However, other
less common use cases for send can end up seeing inodes with a link count
of zero and in this case the send operation fails with a ENOENT error
because any attempt to generate a path for the inode, with the purpose
of creating it or updating it at the receiver, fails since there are no
inode reference items. One use case it to use a regular subvolume for
a send operation after turning it to RO mode or turning a RW snapshot
into RO mode and then using it for a send operation. In both cases, if a
file gets all its hard links deleted while there is an open file
descriptor before turning the subvolume/snapshot into RO mode, the send
operation will encounter an inode with a link count of zero and then
fail with errno ENOENT.

Example using a full send with a subvolume:

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt

  $ btrfs subvolume create /mnt/sv1
  $ touch /mnt/sv1/foo
  $ touch /mnt/sv1/bar

  # keep an open file descriptor on file bar
  $ exec 73</mnt/sv1/bar
  $ unlink /mnt/sv1/bar

  # Turn the subvolume to RO mode and use it for a full send, while
  # holding the open file descriptor.
  $ btrfs property set /mnt/sv1 ro true

  $ btrfs send -f /tmp/full.send /mnt/sv1
  At subvol /mnt/sv1
  ERROR: send ioctl failed with -2: No such file or directory

Example using an incremental send with snapshots:

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt

  $ btrfs subvolume create /mnt/sv1
  $ touch /mnt/sv1/foo
  $ touch /mnt/sv1/bar

  $ btrfs subvolume snapshot -r /mnt/sv1 /mnt/snap1

  $ echo "hello world" >> /mnt/sv1/bar

  $ btrfs subvolume snapshot -r /mnt/sv1 /mnt/snap2

  # Turn the second snapshot to RW mode and delete file foo while
  # holding an open file descriptor on it.
  $ btrfs property set /mnt/snap2 ro false
  $ exec 73</mnt/snap2/foo
  $ unlink /mnt/snap2/foo

  # Set the second snapshot back to RO mode and do an incremental send.
  $ btrfs property set /mnt/snap2 ro true

  $ btrfs send -f /tmp/inc.send -p /mnt/snap1 /mnt/snap2
  At subvol /mnt/snap2
  ERROR: send ioctl failed with -2: No such file or directory

So fix this by ignoring inodes with a link count of zero if we are either
doing a full send or if they do not exist in the parent snapshot (they
are new in the send snapshot), and unlink all paths found in the parent
snapshot when doing an incremental send (and ignoring all other inode
items, such as xattrs and extents).

A test case for fstests follows soon.

CC: stable@vger.kernel.org # 4.4+
Reported-by: Martin Wilck <martin.wilck@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:59 +02:00
Filipe Manana
0d836392ca Btrfs: fix mount failure after fsync due to hard link recreation
If we end up with logging an inode reference item which has the same name
but different index from the one we have persisted, we end up failing when
replaying the log with an errno value of -EEXIST. The error comes from
btrfs_add_link(), which is called from add_inode_ref(), when we are
replaying an inode reference item.

Example scenario where this happens:

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt

  $ touch /mnt/foo
  $ ln /mnt/foo /mnt/bar

  $ sync

  # Rename the first hard link (foo) to a new name and rename the second
  # hard link (bar) to the old name of the first hard link (foo).
  $ mv /mnt/foo /mnt/qwerty
  $ mv /mnt/bar /mnt/foo

  # Create a new file, in the same parent directory, with the old name of
  # the second hard link (bar) and fsync this new file.
  # We do this instead of calling fsync on foo/qwerty because if we did
  # that the fsync resulted in a full transaction commit, not triggering
  # the problem.
  $ touch /mnt/bar
  $ xfs_io -c "fsync" /mnt/bar

  <power fail>

  $ mount /dev/sdb /mnt
  mount: mount /dev/sdb on /mnt failed: File exists

So fix this by checking if a conflicting inode reference exists (same
name, same parent but different index), removing it (and the associated
dir index entries from the parent inode) if it exists, before attempting
to add the new reference.

A test case for fstests follows soon.

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:59 +02:00
Josef Bacik
4559b0a717 btrfs: don't leak ret from do_chunk_alloc
If we're trying to make a data reservation and we have to allocate a
data chunk we could leak ret == 1, as do_chunk_alloc() will return 1 if
it allocated a chunk.  Since the end of the function is the success path
just return 0.

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:59 +02:00
David Sterba
84db5ccf42 btrfs: merge free_fs_root helpers
The exported helper just calls the static one. There's no obvious reason
to have them separate eg. for performance reasons where the static one
could be better optimized in the same unit. There's a slight decrease in
code size and stack consumption.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:59 +02:00
David Sterba
2ffad70ed3 btrfs: constify strings passed to assertion helper
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:59 +02:00
David Sterba
e9539cff04 btrfs: dev-replace: remove unused members of btrfs_dev_replace
Lock owner and nesting level have been unused since day 1, probably
copy&pasted from the extent_buffer locking scheme without much thinking.
The locking of device replace is simpler and does not need any lock
nesting.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:58 +02:00
David Sterba
e17385ca29 btrfs: remove unused member btrfs_root::name
Added in 58176a9604 ("Btrfs: Add per-root block accounting and sysfs
entries") in 2007, the roots had names exported in sysfs. The code
was commented out in 4df27c4d5c ("Btrfs: change how subvolumes
are organized") and cleaned by 182608c829 ("btrfs: remove old
unused commented out code").

Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:58 +02:00
Adam Borowski
616d374efa btrfs: allow defrag on a file opened read-only that has rw permissions
Requiring a read-write descriptor conflicts both ways with exec,
returning ETXTBSY whenever you try to defrag a program that's currently
being run, or causing intermittent exec failures on a live system being
defragged.

As defrag doesn't change the file's contents in any way, there's no
reason to consider it a rw operation.  Thus, let's check only whether
the file could have been opened rw.  Such access control is still needed
as currently defrag can use extra disk space, and might trigger bugs.

We return EINVAL when the request is invalid; here it's ok but merely
the user has insufficient privileges.  Thus, the EPERM return value
reflects the error better -- as discussed in the identical case for
dedupe.

According to codesearch.debian.net, no userspace program distinguishes
these values beyond strerror().

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Reviewed-by: David Sterba <dsterba@suse.com>
[ fold the EPERM patch from Adam ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:58 +02:00
Josef Bacik
3c4276936f Btrfs: fix btrfs_write_inode vs delayed iput deadlock
We recently ran into the following deadlock involving
btrfs_write_inode():

[  +0.005066]  __schedule+0x38e/0x8c0
[  +0.007144]  schedule+0x36/0x80
[  +0.006447]  bit_wait+0x11/0x60
[  +0.006446]  __wait_on_bit+0xbe/0x110
[  +0.007487]  ? bit_wait_io+0x60/0x60
[  +0.007319]  __inode_wait_for_writeback+0x96/0xc0
[  +0.009568]  ? autoremove_wake_function+0x40/0x40
[  +0.009565]  inode_wait_for_writeback+0x21/0x30
[  +0.009224]  evict+0xb0/0x190
[  +0.006099]  iput+0x1a8/0x210
[  +0.006103]  btrfs_run_delayed_iputs+0x73/0xc0
[  +0.009047]  btrfs_commit_transaction+0x799/0x8c0
[  +0.009567]  btrfs_write_inode+0x81/0xb0
[  +0.008008]  __writeback_single_inode+0x267/0x320
[  +0.009569]  writeback_sb_inodes+0x25b/0x4e0
[  +0.008702]  wb_writeback+0x102/0x2d0
[  +0.007487]  wb_workfn+0xa4/0x310
[  +0.006794]  ? wb_workfn+0xa4/0x310
[  +0.007143]  process_one_work+0x150/0x410
[  +0.008179]  worker_thread+0x6d/0x520
[  +0.007490]  kthread+0x12c/0x160
[  +0.006620]  ? put_pwq_unlocked+0x80/0x80
[  +0.008185]  ? kthread_park+0xa0/0xa0
[  +0.007484]  ? do_syscall_64+0x53/0x150
[  +0.007837]  ret_from_fork+0x29/0x40

Writeback calls:

btrfs_write_inode
  btrfs_commit_transaction
    btrfs_run_delayed_iputs

If iput() is called on that same inode, evict() will wait for writeback
forever.

btrfs_write_inode() was originally added way back in 4730a4bc5b
("btrfs_dirty_inode") to support O_SYNC writes. However, ->write_inode()
hasn't been used for O_SYNC since 148f948ba8 ("vfs: Introduce new
helpers for syncing after writing to O_SYNC file or IS_SYNC inode"), so
btrfs_write_inode() is actually unnecessary (and leads to a bunch of
unnecessary commits). Get rid of it, which also gets rid of the
deadlock.

CC: stable@vger.kernel.org # 3.2+
Signed-off-by: Josef Bacik <jbacik@fb.com>
[Omar: new commit message]
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:58 +02:00
Nikolay Borisov
97aff912a2 btrfs: Remove fs_info from btrfs_finish_chunk_alloc
It can be referenced from the passed transaction handle.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:58 +02:00
Nikolay Borisov
f4208794d0 btrfs: Remove fs_info form btrfs_free_chunk
It can be referenced from the passed transaction handle.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:57 +02:00
Nikolay Borisov
4f5ad7bd63 btrfs: Remove fs_info from btrfs_destroy_dev_replace_tgtdev
This function is always passed a well-formed tgtdevice so the fs_info
can be referenced from there.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:57 +02:00
Nikolay Borisov
d6507cf1e2 btrfs: Remove fs_info from btrfs_assign_next_active_device
It can be referenced from the passed 'device' argument which is always
a well-formed device.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:57 +02:00
Nikolay Borisov
5495f195fc btrfs: remove fs_info argument from update_dev_stat_item
It can be referenced from the passed transaction handle.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:57 +02:00
Nikolay Borisov
68a9db5f23 btrfs: Remove fs_info from btrfs_rm_dev_replace_remove_srcdev
It can be referenced from the passed srcdev argument.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:57 +02:00
Nikolay Borisov
8e87e85627 btrfs: Remove fs_info argument from btrfs_add_dev_item
It can be referenced form the passed transaction handle.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:56 +02:00
Qu Wenruo
5e23a6fea6 btrfs: extent-tree: Remove dead alignment check
In find_free_extent() under checks: label, we have the following code:

		search_start = ALIGN(offset, fs_info->stripesize);
		/* move on to the next group */
		if (search_start + num_bytes >
		    block_group->key.objectid + block_group->key.offset) {
			btrfs_add_free_space(block_group, offset, num_bytes);
			goto loop;
		}
		if (offset < search_start)
			btrfs_add_free_space(block_group, offset,
					     search_start - offset);
		BUG_ON(offset > search_start);

However ALIGN() is rounding up, thus @search_start >= @offset and that
BUG_ON() will never be triggered.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:56 +02:00
Filipe Manana
ca5d2ba1ae Btrfs: remove unused key assignment when doing a full send
At send.c:full_send_tree() we were setting the 'key' variable in the loop
while never using it later. We were also using two btrfs_key variables
to store the initial key for search and the key found in every iteration
of the loop. So remove this useless key assignment and use the same
btrfs_key variable to store the initial search key and the key found in
each iteration. This was introduced in the initial send commit but was
never used (commit 31db9f7c23 ("Btrfs: introduce BTRFS_IOC_SEND for
btrfs send/receive").

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:56 +02:00
David Sterba
5cdc84bfde btrfs: drop extent_io_ops::set_range_writeback callback
The data and metadata callback implementation both use the same
function. We can remove the call indirection and intermediate helper
completely.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:56 +02:00
David Sterba
00032d38ea btrfs: drop extent_io_ops::merge_bio_hook callback
The data and metadata callback implementation both use the same
function. We can remove the call indirection completely.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:56 +02:00
David Sterba
05912a3c04 btrfs: drop extent_io_ops::tree_fs_info callback
All implementations of the callback are trivial and do the same and
there's only one user. Merge everything together.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:55 +02:00
David Sterba
e288c080dd btrfs: unify end_io callbacks of async_submit_bio
The end_io callbacks passed to btrfs_wq_submit_bio
(btrfs_submit_bio_done and btree_submit_bio_done) are effectively the
same code, there's no point to do the indirection. Export
btrfs_submit_bio_done and call it directly.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:55 +02:00
David Sterba
d7cbfafc4b btrfs: remove unused member async_submit_bio::bio_flags
After splitting the start and end hooks in a758781d4b ("btrfs:
separate types for submit_bio_start and submit_bio_done"), some of
the function arguments were dropped but not removed from the structure.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:55 +02:00
David Sterba
d7e8555b1d btrfs: remove unused member async_submit_bio::fs_info
Introduced by c6100a4b4e ("Btrfs: replace tree->mapping with
tree->private_data") to be used in run_one_async_done where it got
unused after 736cd52e0c ("Btrfs: remove nr_async_submits and
async_submit_draining").

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:55 +02:00
Gu Jinxiang
315409b009 btrfs: validate type when reading a chunk
Reported in https://bugzilla.kernel.org/show_bug.cgi?id=199839, with an
image that has an invalid chunk type but does not return an error.

Add chunk type check in btrfs_check_chunk_valid, to detect the wrong
type combinations.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=199839
Reported-by: Xu Wen <wen.xu@gatech.edu>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:55 +02:00
Nikolay Borisov
b0132a3be5 btrfs: Rename EXTENT_BUFFER_DUMMY to EXTENT_BUFFER_UNMAPPED
EXTENT_BUFFER_DUMMY is an awful name for this flag. Buffers which have
this flag set are not in any way dummy. Rather, they are private in the
sense that are not mapped and linked to the global buffer tree. This
flag has subtle implications to the way free_extent_buffer works for
example, as well as controls whether page->mapping->private_lock is held
during extent_buffer release. Pages for an unmapped buffer cannot be
under io, nor can they be written by a 3rd party so taking the lock is
unnecessary.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ EXTENT_BUFFER_UNMAPPED, update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:55 +02:00
Nikolay Borisov
07e21c4dad btrfs: Document locking requirement via lockdep_assert_held
Remove stale comment since there is no longer an eb->eb_lock and
document the locking expectation with a lockdep_assert_held statement.
No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:54 +02:00
David Sterba
55ac01396a btrfs: rename btrfs_release_extent_buffer_page
The function used to release one page (and always the first one), but
not anymore since a50924e3a4 ("btrfs: drop constant param
from btrfs_release_extent_buffer_page").  Update the name and comment.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:54 +02:00
Nikolay Borisov
d64766fdf9 btrfs: Refactor loop in btrfs_release_extent_buffer_page
The purpose of the function is to free all the pages comprising an
extent buffer. This can be achieved with a simple for loop rather than
the slightly more involved 'do {} while' construct. So rewrite the
loop using a 'for' construct. Additionally we can never have an
extent_buffer that has 0 pages so remove the check for index == 0. No
functional changes.

The reversed order used to have a meaning in the past where the first
page served as a blocking point for several callers. See eg
4f2de97ace ("Btrfs: set page->private to the eb").

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:54 +02:00
Nikolay Borisov
b16d011e79 btrfs: Reword dodgy comments in alloc_extent_buffer
Commit eb14ab8ed2 ("Btrfs: fix page->private races") fixed a genuine
race between extent buffer initialisation and btree_releasepage.
Unfortunately as the code has evolved the comments weren't changed which
made them slightly wrong and they weren't very clear in the fist place.
Fix this by (hopefully) rewording them in a more approachable manner.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:54 +02:00
Nikolay Borisov
28187ae569 btrfs: Simplify page unlocking in alloc_extent_buffer
Current version of the page unlocking code was added in
727011e07c ("Btrfs: allow metadata blocks larger than the page size")
but even in this commit that particular flag was never used per-se. In
fact, btrfs only uses PageChecked for data pages to identify pages
which have been dirtied but don't have ORDERED bit set. For more
information see 247e743cbe ("Btrfs: Use async helpers to deal with
pages that have been improperly dirtied").

However, this doesn't apply to extent buffer pages. The important bit
here is that the pages are unlocked AFTER the extent buffer has been
properly recorded in the radix tree to avoid races with
btree_releasepage. Let's exploit this fact and simplify the page
unlocking sequence by unlocking the pages in-order and removing the
redundant PageChecked flag setting/clearing.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:54 +02:00
Qu Wenruo
8b9b6f2554 btrfs: scrub: cleanup the remaining nodatasum fixup code
Remove the remaining code that misused the page cache pages during
device replace and could cause data corruption for compressed nodatasum
extents. Such files do not normally exist but there's a bug that allows
this combination and the corruption was exposed by device replace fixup
code.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:53 +02:00
David Sterba
46df06b85e btrfs: refactor block group replication factor calculation to a helper
There are many places that open code the duplicity factor of the block
group profiles, create a common helper. This can be easily extended for
more copies.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:53 +02:00
Anand Jain
321a4bf72b btrfs: use the assigned fs_devices instead of the dereference
We have assigned the %fs_info->fs_devices in %fs_devices as its not
modified just use it for the mutex_lock().

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:53 +02:00
Lu Fengqi
62088ca742 btrfs: qgroup: Drop fs_info parameter from qgroup_rescan_leaf
It can be fetched from the transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:53 +02:00
Lu Fengqi
a937742250 btrfs: qgroup: Drop fs_info parameter from btrfs_qgroup_inherit
It can be fetched from the transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:53 +02:00
Lu Fengqi
280f8bd2cb btrfs: qgroup: Drop fs_info parameter from btrfs_run_qgroups
It can be fetched from the transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:52 +02:00
Lu Fengqi
8696d76045 btrfs: qgroup: Drop fs_info parameter from btrfs_qgroup_account_extent
It can be fetched from the transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:52 +02:00
Lu Fengqi
deb4062743 btrfs: qgroup: Drop root parameter from btrfs_qgroup_trace_subtree
The fs_info can be fetched from the transaction handle directly.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:52 +02:00
Lu Fengqi
8d38d7eb7b btrfs: qgroup: Drop fs_info parameter from btrfs_qgroup_trace_leaf_items
It can be fetched from the transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:52 +02:00
Lu Fengqi
a95f3aafd6 btrfs: qgroup: Drop fs_info parameter from btrfs_qgroup_trace_extent
It can be fetched from the transaction handle. In addition, remove the
WARN_ON(trans == NULL) because it's not possible to hit this condition.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:52 +02:00
Lu Fengqi
f0042d5e92 btrfs: qgroup: Drop fs_info parameter from btrfs_limit_qgroup
It can be fetched from the transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:51 +02:00
Lu Fengqi
3efbee1d00 btrfs: qgroup: Drop fs_info parameter from btrfs_remove_qgroup
It can be fetched from the transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:51 +02:00
Lu Fengqi
49a05ecde3 btrfs: qgroup: Drop fs_info parameter from btrfs_create_qgroup
It can be fetched from the transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:51 +02:00
Lu Fengqi
39616c2735 btrfs: qgroup: Drop fs_info parameter from btrfs_del_qgroup_relation
It can be fetched from the transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:51 +02:00
Lu Fengqi
6b36f1aa5c btrfs: qgroup: Drop fs_info parameter from __del_qgroup_relation
It can be fetched from the transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:51 +02:00
Lu Fengqi
9f8a6ce6ba btrfs: qgroup: Drop fs_info parameter from btrfs_add_qgroup_relation
It can be fetched from the transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:51 +02:00
Lu Fengqi
2e980acdd8 btrfs: qgroup: Drop quota_root and fs_info parameters from update_qgroup_status_item
They can be fetched from the transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:50 +02:00
Lu Fengqi
3e07e9a09f btrfs: qgroup: Drop root parameter from update_qgroup_info_item
It can be fetched from the transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:50 +02:00
Lu Fengqi
ac8a866af1 btrfs: qgroup: Drop root parameter from update_qgroup_limit_item
It can be fetched from the transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:50 +02:00
Lu Fengqi
69104618f4 btrfs: qgroup: Drop quota_root parameter from del_qgroup_item
It can be fetched from the transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:50 +02:00
Lu Fengqi
99d7f09ac0 btrfs: qgroup: Drop quota_root parameter from del_qgroup_relation_item
It can be fetched from the transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:50 +02:00
Lu Fengqi
711169c40f btrfs: qgroup: Drop quota_root parameter from add_qgroup_relation_item
It can be fetched from the transaction handle.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:49 +02:00
Anand Jain
fa59f27c8c btrfs: rename btrfs_parse_early_options
Rename btrfs_parse_early_options() to btrfs_parse_device_options(). As
btrfs_parse_early_options() parses the -o device options and scan the
device provided. So this rename specifies its action. Also the function
name is in line with btrfs_parse_subvol_options().
No functional changes.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:49 +02:00
Lu Fengqi
c8389d4c0d btrfs: qgroup: cleanup the unused srcroot from btrfs_qgroup_inherit
Since commit 0b246afa62 ("btrfs: root->fs_info cleanup, add fs_info
convenience variables"), the srcroot is no longer used to get
fs_info::nodesize.  In fact, it can be dropped after commit 707e8a0715
("btrfs: use nodesize everywhere, kill leafsize").

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:49 +02:00
Qu Wenruo
031f24da2c btrfs: Use btrfs_mark_bg_unused to replace open code
Introduce a small helper, btrfs_mark_bg_unused(), to acquire locks and
add a block group to unused_bgs list.

No functional modification, and only 3 callers are involved.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:49 +02:00
Nikolay Borisov
2556fbb0be btrfs: Rewrite retry logic in do_chunk_alloc
do_chunk_alloc implements logic to detect whether there is currently
pending chunk allocation (by means of space_info->chunk_alloc being
set) and if so it loops around to the 'again' label. Additionally,
based on the state of the space_info (e.g. whether it's full or not)
and the return value of should_alloc_chunk() it decides whether this
is a "hard" error (ENOSPC) or we can just return 0.

This patch refactors all of this:

1. Put order to the scattered ifs handling the various cases in an
easy-to-read if {} else if{} branches. This makes clear the various
cases we are interested in handling.

2. Call should_alloc_chunk only once and use the result in the
if/else if constructs. All of this is done under space_info->lock, so
even before multiple calls of should_alloc_chunk were unnecessary.

3. Rewrite the "do {} while()" loop currently implemented via label
into an explicit loop construct.

4. Move the mutex locking for the case where the caller is the one doing
the allocation. For the case where the caller needs to wait a concurrent
allocation, introduce a pair of mutex_lock/mutex_unlock to act as a
barrier and reword the comment.

5. Switch local vars to bool type where pertinent.

All in all this shouldn't introduce any functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:49 +02:00
Ethan Lien
dec59fa3a7 btrfs: use customized batch size for total_bytes_pinned
In commit b150a4f10d ("Btrfs: use a percpu to keep track of possibly
pinned bytes") we use total_bytes_pinned to track how many bytes we are
going to free in this transaction. When we are close to ENOSPC, we check it
and know if we can make the allocation by commit the current transaction.
For every data/metadata extent we are going to free, we add
total_bytes_pinned in btrfs_free_extent() and btrfs_free_tree_block(), and
release it in unpin_extent_range() when we finish the transaction. So this
is a variable we frequently update but rarely read - just the suitable
use of percpu_counter. But in previous commit we update total_bytes_pinned
by default 32 batch size, making every update essentially a spin lock
protected update. Since every spin lock/unlock operation involves syncing
a globally used variable and some kind of barrier in a SMP system, this is
more expensive than using total_bytes_pinned as a simple atomic64_t.

So fix this by using a customized batch size. Since we only read
total_bytes_pinned when we are close to ENOSPC and fail to allocate new
chunk, we can use a really large batch size and have nearly no penalty
in most cases.

[Test]
We tested the patch on a 4-cores x86 machine:

1. fallocate a 16GiB size test file
2. take snapshot (so all following writes will be COW)
3. run a 180 sec, 4 jobs, 4K random write fio on test file

We also added a temporary lockdep class on percpu_counter's spin lock
used by total_bytes_pinned to track it by lock_stat.

[Results]
unpatched:
lock_stat version 0.4
-----------------------------------------------------------------------
                              class name    con-bounces    contentions
waittime-min   waittime-max waittime-total   waittime-avg    acq-bounces
acquisitions   holdtime-min   holdtime-max holdtime-total   holdtime-avg

               total_bytes_pinned_percpu:            82             82
        0.21           0.61          29.46           0.36         298340
      635973           0.09          11.01      173476.25           0.27

patched:
lock_stat version 0.4
-----------------------------------------------------------------------
                              class name    con-bounces    contentions
waittime-min   waittime-max waittime-total   waittime-avg    acq-bounces
acquisitions   holdtime-min   holdtime-max holdtime-total   holdtime-avg

               total_bytes_pinned_percpu:             1              1
        0.62           0.62           0.62           0.62          13601
       31542           0.14           9.61       11016.90           0.35

[Analysis]
Since the spin lock only protects a single in-memory variable, the
contentions (number of lock acquisitions that had to wait) in both
unpatched and patched version are low. But when we see acquisitions and
acq-bounces, we get much lower counts in patched version. Here the most
important metric is acq-bounces. It means how many times the lock gets
transferred between different cpus, so the patch can really reduce
cacheline bouncing of spin lock (also the global counter of percpu_counter)
in a SMP system.

Fixes: b150a4f10d ("Btrfs: use a percpu to keep track of possibly pinned bytes")
Signed-off-by: Ethan Lien <ethanlien@synology.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:48 +02:00
Ethan Lien
d814a49198 btrfs: use correct compare function of dirty_metadata_bytes
We use customized, nodesize batch value to update dirty_metadata_bytes.
We should also use batch version of compare function or we will easily
goto fast path and get false result from percpu_counter_compare().

Fixes: e2d845211e ("Btrfs: use percpu counter for dirty metadata count")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Ethan Lien <ethanlien@synology.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:48 +02:00
Gu Jinxiang
36350e95a2 btrfs: return device pointer from btrfs_scan_one_device
Return device pointer (with the IS_ERR semantics) from
btrfs_scan_one_device so we don't have to return in through pointer.

And since btrfs_fs_devices can be obtained from btrfs_device, return that.

Signed-off-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ fixed conflics after recent changes to btrfs_scan_one_device ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:48 +02:00
Gu Jinxiang
d64dcbd183 btrfs: make fs_devices a local variable in btrfs_parse_early_options
fs_devices is always passed to btrfs_scan_one_device which overrides it.
In the call stack below fs_devices is passed to btrfs_scan_one_device
from btrfs_mount_root.  In btrfs_mount_root the output fs_devices of
this call stack is not used.

btrfs_mount_root
  btrfs_parse_early_options
    btrfs_scan_one_device

So, it is not necessary to pass fs_devices from btrfs_mount_root, using
a local variable in btrfs_parse_early_options is enough.

Signed-off-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Reviewed-by: Anand Jain <Anand.Jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:48 +02:00
David Sterba
81ffd56b57 btrfs: fix mount and ioctl device scan ioctl race
Technically this extends the critical section covered by uuid_mutex to:

- parse early mount options -- here we can call device scan on paths
  that can be passed as 'device=/dev/...'

- scan the device passed to mount

- open the devices related to the fs_devices -- this increases
  fs_devices::opened

The race can happen when mount calls one of the scans and there's
another one called eg. by mkfs or 'btrfs dev scan':

Mount                                  Scan
-----                                  ----
scan_one_device (dev1, fsid1)
                                       scan_one_device (dev2, fsid1)
				           add the device
					   free stale devices
					       fsid1 fs_devices::opened == 0
					           find fsid1:dev1
					           free fsid1:dev1
					           if it's the last one,
					            free fs_devices of fsid1
						    too

open_devices (dev1, fsid1)
   dev1 not found

When fixed, the uuid mutex will make sure that mount will increase
fs_devices::opened and this will not be touched by the racing scan
ioctl.

Reported-and-tested-by: syzbot+909a5177749d7990ffa4@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+ceb2606025ec1cc3479c@syzkaller.appspotmail.com
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:48 +02:00
David Sterba
399f7f4c42 btrfs: reorder initialization before the mount locks uuid_mutex
In preparation to take a big lock, move resource initialization before
the critical section. It's not obvious from the diff, the desired order
is:

- initialize mount security options
- allocate temporary fs_info
- allocate superblock buffers

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:48 +02:00
David Sterba
5139cff598 btrfs: lift uuid_mutex to callers of btrfs_parse_early_options
Prepartory work to fix race between mount and device scan.

btrfs_parse_early_options calls the device scan from mount and we'll
need to let mount completely manage the critical section.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:47 +02:00
David Sterba
f5194e34ca btrfs: lift uuid_mutex to callers of btrfs_open_devices
Prepartory work to fix race between mount and device scan.

The callers will have to manage the critical section, eg. mount wants to
scan and then call btrfs_open_devices without the ioctl scan walking in
and modifying the fs devices in the meantime.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:47 +02:00
David Sterba
899f9307c3 btrfs: lift uuid_mutex to callers of btrfs_scan_one_device
Prepartory work to fix race between mount and device scan.

The callers will have to manage the critical section, eg. mount wants to
scan and then call btrfs_open_devices without the ioctl scan walking in
and modifying the fs devices in the meantime.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:47 +02:00
Anand Jain
7bcb8164ad btrfs: use device_list_mutex when removing stale devices
btrfs_free_stale_devices() finds a stale (not opened) device matching
path in the fs_uuid list. We are already under uuid_mutex so when we
check for each fs_devices, hold the device_list_mutex too.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:47 +02:00
Anand Jain
fa6d2ae540 btrfs: rename local devices for fs_devices in btrfs_free_stale_devices(
Over the years we named %fs_devices and %devices to represent the
struct btrfs_fs_devices and the struct btrfs_device. So follow the same
scheme here too. No functional changes.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:47 +02:00
Anand Jain
9c6d173ea6 btrfs: extend locked section when adding a new device in device_list_add
Make sure the device_list_lock is held the whole time:

* when the device is being looked up
* new device is initialized and put to the list
* the list counters are updated (fs_devices::opened, fs_devices::total_devices)

Signed-off-by: Anand Jain <anand.jain@oracle.com>
[ update changelog ]
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:46 +02:00
Anand Jain
4306a97449 btrfs: do btrfs_free_stale_devices outside of device_list_add
btrfs_free_stale_devices() looks for device path reused for another
filesystem, and deletes the older fs_devices::device entry.

In preparation to handle locking in device_list_add, move
btrfs_free_stale_devices outside as these two functions serve a
different purpose.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:46 +02:00
Nikolay Borisov
959b1c0467 btrfs: close devices without offloading to a temporary list
Since commit 88c14590cd ("btrfs: use RCU in btrfs_show_devname for
device list traversal") btrfs_show_devname no longer takes
device_list_mutex. As such the deadlock that 0ccd05285e ("btrfs: fix a
possible umount deadlock") aimed to fix no longer exists, we can free
the devices immediatelly and remove the code that does the pending work.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
[ update changelog ]
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:46 +02:00
Qu Wenruo
621567a28c btrfs: Remove unused function btrfs_account_dev_extents_size
This function is not used since the alloc_start parameter has been
obsoleted in commit 0d0c71b317 ("btrfs: obsolete and remove
mount option alloc_start").

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:46 +02:00
Gu Jinxiang
93b9bcdf9f btrfs: remove unused parameter from btrfs_parse_subvol_options
Since parameter flags is no more used since commit d740760656 ("btrfs:
split parse_early_options() in two"), remove it.

Signed-off-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:46 +02:00
Anand Jain
b4993e64f7 btrfs: fix in-memory value of total_devices after seed device deletion
In case of deleting the seed device the %cur_devices (seed) and the
%fs_devices (parent) are different. Now, as the parent
fs_devices::total_devices also maintains the total number of devices
including the seed device, so decrement its in-memory value for the
successful seed delete. We are already updating its corresponding
on-disk btrfs_super_block::number_devices value.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:45 +02:00
Nikolay Borisov
340f1aa27f btrfs: qgroups: Move transaction management inside btrfs_quota_enable/disable
Commit 5d23515be6 ("btrfs: Move qgroup rescan on quota enable to
btrfs_quota_enable") not only resulted in an easier to follow code but
it also introduced a subtle bug. It changed the timing when the initial
transaction rescan was happening:

- before the commit: it would happen after transaction commit had occured
- after the commit: it might happen before the transaction was committed

This results in failure to correctly rescan the quota since there could
be data which is still not committed on disk.

This patch aims to fix this by moving the transaction creation/commit
inside btrfs_quota_enable, which allows to schedule the quota commit
after the transaction has been committed.

Fixes: 5d23515be6 ("btrfs: Move qgroup rescan on quota enable to btrfs_quota_enable")
Reported-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Link: https://marc.info/?l=linux-btrfs&m=152999289017582
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:45 +02:00
David Sterba
c7b562c548 btrfs: raid56: catch errors from full_stripe_write
Add fall-back code to catch failure of full_stripe_write. Proper error
handling from inside run_plug would need more code restructuring as it's
called at arbitrary points by io scheduler.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:45 +02:00
David Sterba
176571a1f6 btrfs: raid56: merge rbio_is_full helpers
There's only one call site of the unlocked helper so it can be folded
into the caller.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:45 +02:00
David Sterba
a81b747d0f btrfs: raid56: use new helper for async_scrub_parity
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:45 +02:00
David Sterba
e66d8d5a41 btrfs: raid56: use new helper for async_read_rebuild
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:45 +02:00
David Sterba
cf6a4a7587 btrfs: raid56: use new helper for async_rmw_stripe
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:44 +02:00
David Sterba
ac63885907 btrfs: raid56: add new helper for starting async work
Add helper that schedules a given function to run on the rmw workqueue.
This will replace several standalone helpers.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:44 +02:00
David Sterba
ebcc326316 btrfs: open-code bio_set_op_attrs
The helper is trivial and marked as deprecated.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:44 +02:00
David Sterba
cc5e31a477 btrfs: switch types to int when counting eb pages
The loops iterating eb pages use unsigned long, that's an overkill as
we know that there are at most 16 pages (64k / 4k), and 4 by default
(with nodesize 16k).

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:44 +02:00
David Sterba
8791d43207 btrfs: use round_up wrapper in num_extent_pages
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:44 +02:00
David Sterba
65ad010488 btrfs: pass only eb to num_extent_pages
Almost all callers pass the start and len as 2 arguments but this is not
necessary, all the information is provided by the eb. By reordering the
calls to num_extent_pages, we don't need the local variables with
start/len.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:43 +02:00
David Sterba
d7f663fa3f btrfs: prune unused includes
Remove includes if none of the interfaces and exports is used in the
given source file.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:43 +02:00
David Sterba
69d2480456 btrfs: use copy_page for copying pages instead of memcpy
Use the helper that's possibly optimized for full page copies.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:43 +02:00
David Sterba
3ffbd68c48 btrfs: simplify pointer chasing of local fs_info variables
Functions that get btrfs inode can simply reach the fs_info by
dereferencing the root and this looks a bit more straightforward
compared to the btrfs_sb(...) indirection.

If the transaction handle is available and not NULL it's used instead.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:43 +02:00
David Sterba
3750851562 btrfs: simplify some assignments of inode numbers
There are several places when the btrfs inode is converted to the
generic inode, back to btrfs and then passed to btrfs_ino. We can remove
the extra back and forth conversions.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:43 +02:00
Zhihui Zhang
8f6c72a9e0 Btrfs: free space cache: make sure there is always room for generation number
io_ctl_set_generation() assumes that the generation number shares
the same page with inline CRCs. Let's make sure this is always true.

Signed-off-by: Zhihui Zhang <zzhsuny@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:42 +02:00
Anand Jain
694c51fb2e btrfs: drop unnecessary variable in btrfs_init_new_device
There is only usage of the declared devices variable, instead use its
value directly.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:42 +02:00
Anand Jain
5da54bc138 btrfs: use a temporary variable for fs_devices in btrfs_init_new_device
There are many instances of the %fs_info->fs_devices pointer
dereferences, use a temporary variable instead.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:42 +02:00
Qu Wenruo
389305b2aa btrfs: relocation: Only remove reloc rb_trees if reloc control has been initialized
Invalid reloc tree can cause kernel NULL pointer dereference when btrfs
does some cleanup of the reloc roots.

It turns out that fs_info::reloc_ctl can be NULL in
btrfs_recover_relocation() as we allocate relocation control after all
reloc roots have been verified.
So when we hit: note, we haven't called set_reloc_control() thus
fs_info::reloc_ctl is still NULL.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=199833
Reported-by: Xu Wen <wen.xu@gatech.edu>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Tested-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:42 +02:00
Qu Wenruo
ba480dd4db btrfs: tree-checker: Detect invalid and empty essential trees
A crafted image has empty root tree block, which will later cause NULL
pointer dereference.

The following trees should never be empty:
1) Tree root
   Must contain at least root items for extent tree, device tree and fs
   tree

2) Chunk tree
   Or we can't even bootstrap as it contains the mapping.

3) Fs tree
   At least inode item for top level inode (.).

4) Device tree
   Dev extents for chunks

5) Extent tree
   Must have corresponding extent for each chunk.

If any of them is empty, we are sure the fs is corrupted and no need to
mount it.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=199847
Reported-by: Xu Wen <wen.xu@gatech.edu>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Tested-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:42 +02:00
Qu Wenruo
fce466eab7 btrfs: tree-checker: Verify block_group_item
A crafted image with invalid block group items could make free space cache
code to cause panic.

We could detect such invalid block group item by checking:
1) Item size
   Known fixed value.
2) Block group size (key.offset)
   We have an upper limit on block group item (10G)
3) Chunk objectid
   Known fixed value.
4) Type
   Only 4 valid type values, DATA, METADATA, SYSTEM and DATA|METADATA.
   No more than 1 bit set for profile type.
5) Used space
   No more than the block group size.

This should allow btrfs to detect and refuse to mount the crafted image.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=199849
Reported-by: Xu Wen <wen.xu@gatech.edu>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:41 +02:00
David Sterba
6d8ff4e458 btrfs: annotate unlikely branches after V0 extent type removal
The v0 extent type checks are the right case for the unlikely
annotations as we don't expect to ever see them, so let's give the
compiler some hint.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:41 +02:00
Nikolay Borisov
ba3c2b196b btrfs: Add graceful handling of V0 extents
Following the removal of the v0 handling code let's be courteous and
print an error message when such extents are handled. In the cases
where we have a transaction just abort it, otherwise just call
btrfs_handle_fs_error. Both cases result in the FS being re-mounted RO.

In case the error handling would be too intrusive, leave the BUG_ON in
place, like extent_data_ref_count, other proper handling would catch
that earlier.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:41 +02:00
Nikolay Borisov
a79865c680 btrfs: Remove V0 extent support
The v0 compat code was introduced in commit 5d4f98a28c
("Btrfs: Mixed back reference  (FORWARD ROLLING FORMAT CHANGE)") 9
years ago, which was merged in 2.6.31. This means that the code is
there to support filesystems which are _VERY_ old and if you are using
btrfs on such an old kernel, you have much bigger problems. This coupled
with the fact that no one is likely testing/maintining this code likely
means it has bugs lurking. All things considered I think 43 kernel
releases later it's high time this remnant of the past got removed.

This patch removes all code wrapped in #ifdefs but leaves the BUG_ONs in case
we have a v0 with no support intact as a sort of safety-net.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:41 +02:00
Chengguang Xu
4de426cd39 btrfs: remove unnecessary curly braces in btrfs_get_acl
It's only coding style fix not functinal change.  When if/else has only
one statement then the braces are not needed.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:41 +02:00
Chengguang Xu
dc7789ef87 btrfs: avoid error code override in btrfs_get_acl
It's not good to override the error code when failing from
btrfs_getxattr() in btrfs_get_acl() because it hides the real reason of
the failure.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:40 +02:00
Chengguang Xu
5ee552da50 btrfs: remove unnecessary -ERANGE check in btrfs_get_acl
There is no chance to get into -ERANGE error condition because we first
call btrfs_getxattr to get the length of the attribute, then we do a
subsequent call with the size from the first call.  Between the 2 calls
the size shouldn't change. So remove the unnecessary -ERANGE error
check.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:40 +02:00
Chengguang Xu
7e35eab958 btrfs: replace empty string with NULL when getting attribute length in btrfs_get_acl
In btrfs_get_acl() the first call of btr_getxattr() is for getting the
length of attribute, the value buffer is never used in this case. So
it's better to replace empty string with NULL.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:40 +02:00
Chengguang Xu
ab3629ed86 btrfs: return error instead of crash when detecting unexpected type in btrfs_get_acl
The caller of btrfs_get_acl() checks error condition so there is no
impact from this change. In practice there is no chance to get into
default case of switch statement because VFS has already checked the
type.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:40 +02:00
Su Yue
af431dcb24 btrfs: return EUCLEAN if extent_inline_ref type is invalid
If type of extent_inline_ref found is not expected, filesystem may have
been corrupted, should return EUCLEAN instead of EINVAL.

Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:40 +02:00
Goldwyn Rodrigues
e4af400a9c btrfs: Use iocb to derive pos instead of passing a separate parameter
struct kiocb carries the ki_pos, so there is no need to pass it as
a separate function parameter.

generic_file_direct_write() increments ki_pos, so we now assign pos
after the function.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
[ rename to btrfs_buffered_write ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:40 +02:00
Su Yue
893bf4b115 btrfs: print more details when checking tree block finds a problem
For easier debugging, print eb->start if level is invalid.  Also make
clear if bytenr found is not expected.

Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:39 +02:00
Nikolay Borisov
7b4284de93 btrfs: Streamline memory allocation failure handling in btrfs_add_delayed_tree_ref
Currently the function uses 2 goto labels to properly handle allocation
failures. This could be simplified by simply re-arranging the code so
that allocations are the in the beginning of the function. This allows
to use simple return statements. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:39 +02:00
Qu Wenruo
4379444654 btrfs: Don't remove block group that still has pinned down bytes
[BUG]
Under certain KVM load and LTP tests, it is possible to hit the
following calltrace if quota is enabled:

BTRFS critical (device vda2): unable to find logical 8820195328 length 4096
BTRFS critical (device vda2): unable to find logical 8820195328 length 4096

WARNING: CPU: 0 PID: 49 at ../block/blk-core.c:172 blk_status_to_errno+0x1a/0x30
CPU: 0 PID: 49 Comm: kworker/u2:1 Not tainted 4.12.14-15-default #1 SLE15 (unreleased)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014
Workqueue: btrfs-endio-write btrfs_endio_write_helper [btrfs]
task: ffff9f827b340bc0 task.stack: ffffb4f8c0304000
RIP: 0010:blk_status_to_errno+0x1a/0x30
Call Trace:
 submit_extent_page+0x191/0x270 [btrfs]
 ? btrfs_create_repair_bio+0x130/0x130 [btrfs]
 __do_readpage+0x2d2/0x810 [btrfs]
 ? btrfs_create_repair_bio+0x130/0x130 [btrfs]
 ? run_one_async_done+0xc0/0xc0 [btrfs]
 __extent_read_full_page+0xe7/0x100 [btrfs]
 ? run_one_async_done+0xc0/0xc0 [btrfs]
 read_extent_buffer_pages+0x1ab/0x2d0 [btrfs]
 ? run_one_async_done+0xc0/0xc0 [btrfs]
 btree_read_extent_buffer_pages+0x94/0xf0 [btrfs]
 read_tree_block+0x31/0x60 [btrfs]
 read_block_for_search.isra.35+0xf0/0x2e0 [btrfs]
 btrfs_search_slot+0x46b/0xa00 [btrfs]
 ? kmem_cache_alloc+0x1a8/0x510
 ? btrfs_get_token_32+0x5b/0x120 [btrfs]
 find_parent_nodes+0x11d/0xeb0 [btrfs]
 ? leaf_space_used+0xb8/0xd0 [btrfs]
 ? btrfs_leaf_free_space+0x49/0x90 [btrfs]
 ? btrfs_find_all_roots_safe+0x93/0x100 [btrfs]
 btrfs_find_all_roots_safe+0x93/0x100 [btrfs]
 btrfs_find_all_roots+0x45/0x60 [btrfs]
 btrfs_qgroup_trace_extent_post+0x20/0x40 [btrfs]
 btrfs_add_delayed_data_ref+0x1a3/0x1d0 [btrfs]
 btrfs_alloc_reserved_file_extent+0x38/0x40 [btrfs]
 insert_reserved_file_extent.constprop.71+0x289/0x2e0 [btrfs]
 btrfs_finish_ordered_io+0x2f4/0x7f0 [btrfs]
 ? pick_next_task_fair+0x2cd/0x530
 ? __switch_to+0x92/0x4b0
 btrfs_worker_helper+0x81/0x300 [btrfs]
 process_one_work+0x1da/0x3f0
 worker_thread+0x2b/0x3f0
 ? process_one_work+0x3f0/0x3f0
 kthread+0x11a/0x130
 ? kthread_create_on_node+0x40/0x40
 ret_from_fork+0x35/0x40

BTRFS critical (device vda2): unable to find logical 8820195328 length 16384
BTRFS: error (device vda2) in btrfs_finish_ordered_io:3023: errno=-5 IO failure
BTRFS info (device vda2): forced readonly
BTRFS error (device vda2): pending csums is 2887680

[CAUSE]
It's caused by race with block group auto removal:

- There is a meta block group X, which has only one tree block
  The tree block belongs to fs tree 257.
- In current transaction, some operation modified fs tree 257
  The tree block gets COWed, so the block group X is empty, and marked
  as unused, queued to be deleted.
- Some workload (like fsync) wakes up cleaner_kthread()
  Which will call btrfs_delete_unused_bgs() to remove unused block
  groups.
  So block group X along its chunk map get removed.
- Some delalloc work finished for fs tree 257
  Quota needs to get the original reference of the extent, which will
  read tree blocks of commit root of 257.
  Then since the chunk map gets removed, the above warning gets
  triggered.

[FIX]
Just let btrfs_delete_unused_bgs() skip block group which still has
pinned bytes.

However there is a minor side effect: currently we only queue empty
blocks at update_block_group(), and such empty block group with pinned
bytes won't go through update_block_group() again, such block group
won't be removed, until it gets new extent allocated and removed.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:39 +02:00
Geert Uytterhoeven
bc931c0ef8 btrfs: Refactor count handling in btrfs_unpin_free_ino
With gcc 4.1.2:

    fs/btrfs/inode-map.c: In function ‘btrfs_unpin_free_ino’:
    fs/btrfs/inode-map.c:241: warning: ‘count’ may be used uninitialized in this function

While this warning is a false-positive, it can easily be killed by
refactoring the code.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:39 +02:00
Arnd Bergmann
d3c6be6fda btrfs: use timespec64 for i_otime
While the regular inode timestamps all use timespec64 now, the i_otime
field is btrfs specific and still needs to be converted to correctly
represent times beyond 2038.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:39 +02:00
Arnd Bergmann
afd48513f0 btrfs: use monotonic time for transaction handling
The transaction times were changed to ktime_get_real_seconds to avoid
the y2038 overflow, but they still have a minor problem when they go
backwards or jump due to settimeofday() or leap seconds.

This changes the transaction handling to instead use ktime_get_seconds(),
which returns a CLOCK_MONOTONIC timestamp that has neither of those
problems.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:38 +02:00
Qu Wenruo
e41ca58974 btrfs: Get rid of the confusing btrfs_file_extent_inline_len
We used to call btrfs_file_extent_inline_len() to get the uncompressed
data size of an inlined extent.

However this function is hiding evil, for compressed extent, it has no
choice but to directly read out ram_bytes from btrfs_file_extent_item.
While for uncompressed extent, it uses item size to calculate the real
data size, and ignoring ram_bytes completely.

In fact, for corrupted ram_bytes, due to above behavior kernel
btrfs_print_leaf() can't even print correct ram_bytes to expose the bug.

Since we have the tree-checker to verify all EXTENT_DATA, such mismatch
can be detected pretty easily, thus we can trust ram_bytes without the
evil btrfs_file_extent_inline_len().

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:38 +02:00
Nikolay Borisov
bc877d285c btrfs: Deduplicate extent_buffer init code
When a new extent buffer is allocated there are a few mandatory fields
which need to be set in order for the buffer to be sane: level,
generation, bytenr, backref_rev, owner and FSID/UUID. Currently this
is open coded in the callers of btrfs_alloc_tree_block, meaning it's
fairly high in the abstraction hierarchy of operations. This patch
solves this by simply moving this init code in btrfs_init_new_buffer,
since this is the function which initializes a newly allocated
extent buffer. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:38 +02:00
Qu Wenruo
9912bbf644 btrfs: check-integrity: Fix NULL pointer dereference for degraded mount
Commit f8f84b2dfd ("btrfs: index check-integrity state hash by a dev_t")
changed how btrfsic indexes device state.

Now we need to access device->bdev->bd_dev, while for degraded mount
it's completely possible to have device->bdev as NULL, thus it will
trigger a NULL pointer dereference at mount time.

Fix it by checking if the device is degraded before accessing
device->bdev->bd_dev.

There are a lot of other places accessing device->bdev->bd_dev, however
the other call sites have either checked device->bdev, or the
device->bdev is passed from btrfsic_map_block(), so it won't cause harm.

Fixes: f8f84b2dfd ("btrfs: index check-integrity state hash by a dev_t")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:38 +02:00
Nikolay Borisov
43a7e99db6 btrfs: Remove fs_info from btrfs_force_chunk_alloc
It can be referenced from the passed transaction handle.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:38 +02:00
Nikolay Borisov
c83488afc5 btrfs: Remove fs_info from btrfs_inc_block_group_ro
It can be referenced from the passed bg cache.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:37 +02:00
Nikolay Borisov
61da2abfca btrfs: Remove fs_info from btrfs_alloc_logged_file_extent
It can be referenced from trans since the function is always called
within a valid transaction.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:37 +02:00
Nikolay Borisov
87cc7a8a2a btrfs: Remove fs_info from remove_extent_backref
It can be referenced directly from the transaction handle since it's
always valid.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:37 +02:00
Nikolay Borisov
5fac7f9ee1 btrfs: Remove fs_info from run_one_delayed_ref
It can be referenced from the passed transaction handle, since it's
always valid.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:37 +02:00
Nikolay Borisov
a639cdeba3 btrfs: Remove fs_info from insert_inline_extent_backref
It can be referenced from the passed transaction handle, since it's
always valid.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:37 +02:00
Nikolay Borisov
3c4da6574e btrfs: Remove fs_info from exclude_super_stripes
It can be referenced from the passed block group.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:36 +02:00
Nikolay Borisov
9e715da860 btrfs: Remove fs_info from free_excluded_extents
It can be referenced from the passed block group.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:36 +02:00
Nikolay Borisov
451a2c1303 btrfs: Remove fs_info from check_system_chunk
It can be referenced from trans since the function is always called
within a transaction.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:36 +02:00
Nikolay Borisov
c216b2039a btrfs: Remove fs_info from btrfs_alloc_chunk
It can be referenced from trans since the function is always called
within a transaction.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:36 +02:00
Nikolay Borisov
01458828bb btrfs: Remove fs_info from do_chunk_alloc
This function is always called with a valid transaction handle from
where fs_info can be referenced. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:36 +02:00
Nikolay Borisov
f97806f2ee btrfs: Remove fs_info from run_delayed_tree_ref
It can always be referneced from the passed transaction handle since
it's always valid. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:35 +02:00
Nikolay Borisov
f9871eddd9 btrfs: Remove fs_info from cleanup_ref_head
fs_info can be refenreced from the transaction handle, since it's always
valid. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:35 +02:00
Nikolay Borisov
c4d56d4a16 btrfs: Remove unused fs_info from cleanup_extent_op
The argument is no longer used so remove it.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:35 +02:00
Nikolay Borisov
20b9a2d670 btrfs: Remove fs_info from run_delayed_extent_op
This function is always called with a valid transaction handle so
fs_info can be referenced from there. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:35 +02:00
Nikolay Borisov
2bf98ef35f btrfs: Remove fs_info from run_delayed_data_ref
This function is always called with a valid transaction from where
fs_info can be referenced. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:35 +02:00
Nikolay Borisov
2590d0f155 btrfs: Remove fs_info argument from __btrfs_inc_extent_ref
This function already takes a transaction which holds a reference to
the fs_info struct. Use that reference and remove the extra arg. No
functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:35 +02:00
Nikolay Borisov
ef89b8245b btrfs: Remove fs_info from alloc_reserved_file_extent
fs_info can be referenced from the transaction handle, which is always
valid. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:34 +02:00
Nikolay Borisov
e72cb9235d btrfs: Remove fs_info from __btrfs_free_extent
This function is always called with a valid transaction handle so we
can reference the fs_info from there. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:34 +02:00
Nikolay Borisov
5a98ec0141 btrfs: Remove fs_info from btrfs_remove_block_group
This function is always called with a valid transaction handle from
where we can reference fs_info. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:34 +02:00
Nikolay Borisov
e7e02096d9 btrfs: Remove fs_info from btrfs_make_block_group
This function is always called with a valid transaction handle from
where we can reference the fs_info. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:34 +02:00
Nikolay Borisov
88a979c615 btrfs: Remove fs_info from btrfs_add_delayed_data_ref
This function is always called with a valid transaction handle from
where fs_info can be referenced. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:34 +02:00
Nikolay Borisov
44e1c47d5c btrfs: Remove fs_info from btrfs_add_delayed_tree_ref
This function is always called with a valid transaction handle from
where fs_info can be referenced. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:33 +02:00
Nikolay Borisov
fbe4801b26 btrfs: Remove fs_info from lookup_extent_backref
This argument is unused. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:33 +02:00
Nikolay Borisov
bd1d53ef35 btrfs: Remove fs_info argument from lookup_extent_data_ref
This function is always called with a valid transaction handle from
where fs_info can be referenced. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:33 +02:00
Nikolay Borisov
b8582eeabb btrfs: Remove fs_info argument from lookup_tree_block_ref
This function is always called with a valid transaction handle from
where the fs_info can be referenced. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:33 +02:00
Nikolay Borisov
61a18f1c66 btrfs: Remove fs_info argument from update_inline_extent_backref
This function always uses the leaf's extent_buffer which already
contains a reference to the fs_info. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:33 +02:00
Nikolay Borisov
867cc1fbeb btrfs: Remove fs_info from lookup_inline_extent_backref
This function is always called with a valid transaction handle from
where the fs_info can be referenced. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:32 +02:00
Nikolay Borisov
b167fa9152 btrfs: Remove fs_info from fixup_low_keys
This argument is unused. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:32 +02:00
Nikolay Borisov
e9f6290d59 btrfs: Remove fs_info from remove_extent_data_ref
This function is always called with a valid transaction from where the
fs_info can be referenced. No functional change.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:32 +02:00
Nikolay Borisov
375934105c btrfs: Remove fs_info argument from insert_extent_backref
This function is always called with a valid transaction handle from
where fs_info can be referenced. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:32 +02:00
Nikolay Borisov
62b895af40 btrfs: Remove fs_info from insert_extent_data_ref
This function is always called with a valid transaction handle from
where fs_info can be referenced. So remove the redundant argument.
No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:32 +02:00
Nikolay Borisov
10728404c6 btrfs: Remove fs_info from insert_tree_block_ref
This function is always called with a valid transaction so there is no
need to duplicate the fs_info, we can reference it directly from the
trans handle. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:31 +02:00
Bart Van Assche
edf57cbf2b btrfs: Fix a C compliance issue
The C programming language does not allow to use preprocessor statements
inside macro arguments (pr_info() is defined as a macro). Hence rework
the pr_info() statement in btrfs_print_mod_info() such that it becomes
compliant. This patch allows tools like sparse to analyze the BTRFS
source code.

Fixes: 62e855771d ("btrfs: convert printk(KERN_* to use pr_* calls")
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:31 +02:00
Bart Van Assche
acd43e3cdf btrfs: Annotate fall-through when parsing mount option
This patch avoids that the compiler complains that a fall-through
annotation is missing when building with W=1.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:31 +02:00
Bart Van Assche
bece2e8239 btrfs: Fix misleading indentation reported by smatch
This patch avoids that building the BTRFS source code with smatch
triggers complaints about inconsistent indenting.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:31 +02:00
Nikolay Borisov
a9ecb653b0 btrfs: Streamline log_extent_csums a bit
Currently this function takes the root as an argument only to get the
log_root from it. Simplify this by directly passing the log root from
the caller. Also eliminate the fs_info local variable, since it's used
only once, so directly reference it from the transaction handle.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:31 +02:00
David Sterba
ca5788aba3 btrfs: remove remaing full_sync logic from btrfs_sync_file
The logic to check if the inode is already in the log can now be
simplified since we always wait for the ordered extents to complete
before deciding whether the inode needs to be logged. The big comment
about it can go away too.

CC: Filipe Manana <fdmanana@suse.com>
Suggested-by: Filipe Manana <fdmanana@suse.com>
[ code and changelog copied from mail discussion ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:31 +02:00
Josef Bacik
5636cf7d6d btrfs: remove the logged extents infrastructure
This is no longer used anywhere, remove all of it.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:30 +02:00
Josef Bacik
a2120a473a btrfs: clean up the left over logged_list usage
We no longer use this list we've passed around so remove it everywhere.
Also remove the extra checks for ordered/filemap errors as this is
handled higher up now that we're waiting on ordered_extents before
getting to the tree log code.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:30 +02:00
Josef Bacik
e7175a6927 btrfs: remove the wait ordered logic in the log_one_extent path
Since we are waiting on all ordered extents at the start of the fsync()
path we don't need to wait on any logged ordered extents, and we don't
need to look up the checksums on the ordered extents as they will
already be on disk prior to getting here.  Rework this so we're only
looking up and copying the on-disk checksums for the extent range we
care about.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:30 +02:00
Josef Bacik
b5e6c3e170 btrfs: always wait on ordered extents at fsync time
There's a priority inversion that exists currently with btrfs fsync.  In
some cases we will collect outstanding ordered extents onto a list and
only wait on them at the very last second.  However this "very last
second" falls inside of a transaction handle, so if we are in a lower
priority cgroup we can end up holding the transaction open for longer
than needed, so if a high priority cgroup is also trying to fsync()
it'll see latency.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:30 +02:00
Nikolay Borisov
16d1c062c7 btrfs: Fix comment in lookup_inline_extent_backref
The comment wrongfully states that the owner parameter is the level of
the parent block. In fact owner is the level of the current block and
by adding 1 to it we can eventually get to the parent/root.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:30 +02:00
Nikolay Borisov
bd3c685ed9 btrfs: Document __btrfs_inc_extent_ref
Here is a doc-only patch which tires to deobfuscate the terra-incognita
that arguments for delayed refs are.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:29 +02:00
Qu Wenruo
9bebe665c3 btrfs: scrub: Remove unused copy_nocow_pages and its callchain
Since commit ac0b4145d6 ("btrfs: scrub: Don't use inode pages
for device replace") the function is not used and we can remove all
functions down the call chain.

There was an optimization that reused inode pages to speed up device
replace, but broke when there was nodatasum and compressed page. The
potential performance gain is small so we don't loose much by removing
it and using scrub_pages same as the other pages.

Signed-off-by: Qu Wenruo <wqu@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:29 +02:00
Allen Pais
a944442c2b btrfs: replace get_seconds with new 64bit time API
The get_seconds() function is deprecated as it truncates the timestamp
to 32 bits. Change it to or ktime_get_real_seconds().

Signed-off-by: Allen Pais <allen.lkml@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06 13:12:29 +02:00
Al Viro
32955c5422 btrfs: switch to discard_new_inode()
Make sure that no partially set up inodes can be returned by
open-by-handle.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-08-03 16:03:29 -04:00
Linus Torvalds
55b636b419 for-4.18-rc5-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAltSwkIACgkQxWXV+ddt
 WDtMBQ//UXMjHaXvFmC0SM6NczuYQR51hLYtJFIKig93XK5goVpUBTNbxO7LX/Tn
 4zKoKyVhkW1884V6mRiC+G23QLbo0BQZA7DExfyJ3jylQdjZMBm+K+r19OtGQf5v
 CII7oUwni03KIiXIqiFAL5dLWebVQpG5EKJbh8GLZsmg6xNcyVaUqZ/fHXajbZiv
 ldEBtHBKIv7WWTJmylMBKMWnRz+jqU91fXPahoU6R5qivODrLt1o/PMuSjVNhaxe
 iDldHfdOaiQmLHB/1kOGyv492oW5mSSVNDE8LjEDZ61tDNlAcUyuKUWIRBxDEDtD
 6D7rlVQXJ/N7sJ6+UYmJKsRpHL+NOkyzSZ0QEU/sm1Xpm8gkhHuuofRPrVCtd3l1
 ZSbwvlrdyjigVEBfM3IbToQ/K6Rc1ZGId20OAs9PCQbb+mj9IxPIncZ7pI1c4hlh
 pPEjcYsp14JbCTjctFalcqTiFY5tHRQsx+GUFnDyOcdL7Mi+CoH+0Jy61Vgz9GQE
 7s934cfEC0ot/f66kAL/PZzxUfC7TePqaa+sDfS5BIkJ4M6lPMxS5De5R4Z0+Nzr
 DXgQAlgXmxfRjpOYMTH9D0EDdSeJaNmVHgk7hFbiYk/KX3oyd4NmgI9Cfao8rQJv
 2yd8wF2httfSJKD4b/Hv9r6Ho/Bw9PK59BvWOKYhSj6IGl32utw=
 =f7eB
 -----END PGP SIGNATURE-----

Merge tag 'for-4.18-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fix from David Sterba:
 "A fix of a corruption regarding fsync and clone, under some very
  specific conditions explained in the patch.

  The fix is marked for stable 3.16+ so I'd like to get it merged now
  given the impact"

* tag 'for-4.18-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  Btrfs: fix file data corruption after cloning a range and fsync
2018-07-21 16:42:03 -07:00
Filipe Manana
bd3599a0e1 Btrfs: fix file data corruption after cloning a range and fsync
When we clone a range into a file we can end up dropping existing
extent maps (or trimming them) and replacing them with new ones if the
range to be cloned overlaps with a range in the destination inode.
When that happens we add the new extent maps to the list of modified
extents in the inode's extent map tree, so that a "fast" fsync (the flag
BTRFS_INODE_NEEDS_FULL_SYNC not set in the inode) will see the extent maps
and log corresponding extent items. However, at the end of range cloning
operation we do truncate all the pages in the affected range (in order to
ensure future reads will not get stale data). Sometimes this truncation
will release the corresponding extent maps besides the pages from the page
cache. If this happens, then a "fast" fsync operation will miss logging
some extent items, because it relies exclusively on the extent maps being
present in the inode's extent tree, leading to data loss/corruption if
the fsync ends up using the same transaction used by the clone operation
(that transaction was not committed in the meanwhile). An extent map is
released through the callback btrfs_invalidatepage(), which gets called by
truncate_inode_pages_range(), and it calls __btrfs_releasepage(). The
later ends up calling try_release_extent_mapping() which will release the
extent map if some conditions are met, like the file size being greater
than 16Mb, gfp flags allow blocking and the range not being locked (which
is the case during the clone operation) nor being the extent map flagged
as pinned (also the case for cloning).

The following example, turned into a test for fstests, reproduces the
issue:

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt

  $ xfs_io -f -c "pwrite -S 0x18 9000K 6908K" /mnt/foo
  $ xfs_io -f -c "pwrite -S 0x20 2572K 156K" /mnt/bar

  $ xfs_io -c "fsync" /mnt/bar
  # reflink destination offset corresponds to the size of file bar,
  # 2728Kb minus 4Kb.
  $ xfs_io -c ""reflink ${SCRATCH_MNT}/foo 0 2724K 15908K" /mnt/bar
  $ xfs_io -c "fsync" /mnt/bar

  $ md5sum /mnt/bar
  95a95813a8c2abc9aa75a6c2914a077e  /mnt/bar

  <power fail>

  $ mount /dev/sdb /mnt
  $ md5sum /mnt/bar
  207fd8d0b161be8a84b945f0df8d5f8d  /mnt/bar
  # digest should be 95a95813a8c2abc9aa75a6c2914a077e like before the
  # power failure

In the above example, the destination offset of the clone operation
corresponds to the size of the "bar" file minus 4Kb. So during the clone
operation, the extent map covering the range from 2572Kb to 2728Kb gets
trimmed so that it ends at offset 2724Kb, and a new extent map covering
the range from 2724Kb to 11724Kb is created. So at the end of the clone
operation when we ask to truncate the pages in the range from 2724Kb to
2724Kb + 15908Kb, the page invalidation callback ends up removing the new
extent map (through try_release_extent_mapping()) when the page at offset
2724Kb is passed to that callback.

Fix this by setting the bit BTRFS_INODE_NEEDS_FULL_SYNC whenever an extent
map is removed at try_release_extent_mapping(), forcing the next fsync to
search for modified extents in the fs/subvolume tree instead of relying on
the presence of extent maps in memory. This way we can continue doing a
"fast" fsync if the destination range of a clone operation does not
overlap with an existing range or if any of the criteria necessary to
remove an extent map at try_release_extent_mapping() is not met (file
size not bigger then 16Mb or gfp flags do not allow blocking).

CC: stable@vger.kernel.org # 3.16+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-07-19 15:36:31 +02:00
Linus Torvalds
04a1320651 for-4.18-rc5-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAltPMI0ACgkQxWXV+ddt
 WDvmXw//fyV+2hoARngzjd+4o32YHfxdf+Xv4XCnMsZVKOHKkqX8qrmMNyX0sd4w
 5NwUZpv/mZ4LHnm4M+EMGJWjXL/oXkLGrDzndninNC+u7GlFVieZ/aF5D96z6rOm
 p45wGETYvAbZI7XZ3dLebpIDqr+eXOhx3lpJTAKY5sfTIwzwJ+KC5vFYdt+Rz4cr
 cbjwHhRUsRfu1I0SSjUVFIC5frtegIzbDgjWNiLLO44ozbDAH3j1SufOgNLb5GFM
 n+eh0xIHDNLOrH3aVKO19zk9NigVBu96/FJnIz0+Jzs67hifksfZWVDV5vKetUxA
 M46aqtTrSVb/NJ/RHkQkyWiJjZqioXXx+KsZjdU63fyv4iu0+o2HV0uY/Pifm+X/
 fCS7xbQOhWJySQ+6mAjxXB9eo0RqO+RIGGIV9gJWZKt3S3DvAUmvd980jeHUtXRB
 VwMwmnvqvYaGWLWmaTRm1mjdmhCX2JdNN2RMmVN36tGfed0uopIFeax2rtWJ4153
 V+8eZWaLkvvT3iGu+XLUhEfv3UCUy7N1LDk8toe7Xp+qIMvWus3GIsKAUCmJJ3b+
 sGmbYSgn5v8TR65m5QO4/ZWmt4/bi/2Usd6Cq3vd0Op08kTWBTxjdelAVm+dlEYb
 sZLIMrxPg8ogEw8qX4GxROa8/1z9F/62RSmHfk4W7InY2AMJJAg=
 =Ga4m
 -----END PGP SIGNATURE-----

Merge tag 'for-4.18-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "Three regression fixes. They're few-liners and fixing some corner
  cases missed in the origial patches"

* tag 'for-4.18-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: scrub: Don't use inode page cache in scrub_handle_errored_block()
  btrfs: fix use-after-free of cmp workspace pages
  btrfs: restore uuid_mutex in btrfs_open_devices
2018-07-18 11:13:25 -07:00
Qu Wenruo
665d4953cd btrfs: scrub: Don't use inode page cache in scrub_handle_errored_block()
In commit ac0b4145d6 ("btrfs: scrub: Don't use inode pages for device
replace") we removed the branch of copy_nocow_pages() to avoid
corruption for compressed nodatasum extents.

However above commit only solves the problem in scrub_extent(), if
during scrub_pages() we failed to read some pages,
sctx->no_io_error_seen will be non-zero and we go to fixup function
scrub_handle_errored_block().

In scrub_handle_errored_block(), for sctx without csum (no matter if
we're doing replace or scrub) we go to scrub_fixup_nodatasum() routine,
which does the similar thing with copy_nocow_pages(), but does it
without the extra check in copy_nocow_pages() routine.

So for test cases like btrfs/100, where we emulate read errors during
replace/scrub, we could corrupt compressed extent data again.

This patch will fix it just by avoiding any "optimization" for
nodatasum, just falls back to the normal fixup routine by try read from
any good copy.

This also solves WARN_ON() or dead lock caused by lame backref iteration
in scrub_fixup_nodatasum() routine.

The deadlock or WARN_ON() won't be triggered before commit ac0b4145d6
("btrfs: scrub: Don't use inode pages for device replace") since
copy_nocow_pages() have better locking and extra check for data extent,
and it's already doing the fixup work by try to read data from any good
copy, so it won't go scrub_fixup_nodatasum() anyway.

This patch disables the faulty code and will be removed completely in a
followup patch.

Fixes: ac0b4145d6 ("btrfs: scrub: Don't use inode pages for device replace")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-07-17 13:56:30 +02:00
Naohiro Aota
97b191702b btrfs: fix use-after-free of cmp workspace pages
btrfs_cmp_data_free() puts cmp's src_pages and dst_pages, but leaves
their page address intact. Now, if you hit "goto again" in
btrfs_extent_same_range() and hit some error in
btrfs_cmp_data_prepare(), you'll try to unlock/put already put pages.

This is simple fix to reset the address to avoid use-after-free.

Fixes: 67b07bd4be ("Btrfs: reuse cmp workspace in EXTENT_SAME ioctl")
Signed-off-by: Naohiro Aota <naota@elisp.net>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-07-13 17:31:35 +02:00
David Sterba
20c5bbc640 btrfs: restore uuid_mutex in btrfs_open_devices
Commit 542c5908ab ("btrfs: replace uuid_mutex by
device_list_mutex in btrfs_open_devices") switched to device_list_mutex
as we need that for the device list traversal, but we also need
uuid_mutex to protect access to fs_devices::opened to be consistent with
other users of that.

Fixes: 542c5908ab ("btrfs: replace uuid_mutex by device_list_mutex in btrfs_open_devices")
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-07-13 14:55:46 +02:00
Miklos Szeredi
87eb5eb242 vfs: dedupe: rationalize args
Clean up f_op->dedupe_file_range() interface.

1) Use loff_t for offsets and length instead of u64
2) Order the arguments the same way as {copy|clone}_file_range().

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-07-06 23:57:03 +02:00
Miklos Szeredi
5740c99e9d vfs: dedupe: return int
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-07-06 23:57:03 +02:00
Linus Torvalds
d3bc0e67f8 for-4.18-rc2-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAls4zz0ACgkQxWXV+ddt
 WDs0ZhAAplEAcN1BP986BS7GpjrG20vQtP9AnHlnSEJJJmsnykpspBylOcLRkKjF
 LKBfBPCKqIo7kn5ebKT1Kk7zJPkOOEfmxGW7hffVN/oa/oMtmgJbbHDUgl2TDgdu
 rky1O+Bj+S37s5rhiXAJ4oU9ekdpWIlN30GczfynjiPqGigKh/cINsEEhQIIAiJG
 PRDQfSIJeh67x1AP0KE8sJAYSsaeFxT+kHrT/NPs1NFDSzrQSa/QWPFVjGVVuI/Y
 w84Mo0EqdRV7tap7D3QyWyYea6zdP00PG8TyLl0Kba+LckFbzpNN5hP3SUxleBzL
 0ZBJi7/tOqnrMV3YaGm40dLfgD4B+CFt8zDyg2JvWUxxEzfQfYif7KIT2IV8fSqS
 QrVw2NrzQC7EZ4Zu98wCN7dyyOE8yhqbq805YdG3Nj+zT6DqRu01TBo4Yr/Ek8ux
 +ITAtQVbaOZmTIt/qh/Oxc5jRsurAno1FP3XRH+1hfSlS7xc3LfI1CUbX3jAKzXN
 edxdM4/h+d4nekvROnKBH4EheS6+ZVfgzYlYUW9c2rjcJ1RHhDElbh14+IoM6LKJ
 nJ+Cp+744F6W5jaG3oWElJrdhlY31mWUjiZaj2CHl16EcH3MToytrxKMX+OWo95W
 gChnKicrtpO6+9nbED3Tdhp7SkbDysun6jvEpSgdlm8+2H5Kwrw=
 =KWL7
 -----END PGP SIGNATURE-----

Merge tag 'for-4.18-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "We have a few regression fixes for qgroup rescan status tracking and
  the vm_fault_t conversion that mixed up the error values"

* tag 'for-4.18-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  Btrfs: fix mount failure when qgroup rescan is in progress
  Btrfs: fix regression in btrfs_page_mkwrite() from vm_fault_t conversion
  btrfs: quota: Set rescan progress to (u64)-1 if we hit last leaf
2018-07-01 12:38:16 -07:00
Filipe Manana
e4e7ede739 Btrfs: fix mount failure when qgroup rescan is in progress
If a power failure happens while the qgroup rescan kthread is running,
the next mount operation will always fail. This is because of a recent
regression that makes qgroup_rescan_init() incorrectly return -EINVAL
when we are mounting the filesystem (through btrfs_read_qgroup_config()).
This causes the -EINVAL error to be returned regardless of any qgroup
flags being set instead of returning the error only when neither of
the flags BTRFS_QGROUP_STATUS_FLAG_RESCAN nor BTRFS_QGROUP_STATUS_FLAG_ON
are set.

A test case for fstests follows up soon.

Fixes: 9593bf4967 ("btrfs: qgroup: show more meaningful qgroup_rescan_init error message")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-06-28 11:30:57 +02:00
Chris Mason
717beb96d9 Btrfs: fix regression in btrfs_page_mkwrite() from vm_fault_t conversion
The vm_fault_t conversion commit introduced a ret2 variable for tracking
the integer return values from internal btrfs functions.  It was
sometimes returning VM_FAULT_LOCKED for pages that were actually invalid
and had been removed from the radix.  Something like this:

    ret2 = btrfs_delalloc_reserve_space() // returns zero on success

    lock_page(page)
    if (page->mapping != inode->i_mapping)
	goto out_unlock;

...

out_unlock:
    if (!ret2) {
	    ...
	    return VM_FAULT_LOCKED;
    }

This ends up triggering this WARNING in btrfs_destroy_inode()
    WARN_ON(BTRFS_I(inode)->block_rsv.size);

xfstests generic/095 was able to reliably reproduce the errors.

Since out_unlock: is only used for errors, this fix moves it below the
if (!ret2) check we use to return VM_FAULT_LOCKED for success.

Fixes: a528a24150 (btrfs: change return type of btrfs_page_mkwrite to vm_fault_t)
Signed-off-by: Chris Mason <clm@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-06-28 11:30:50 +02:00
Qu Wenruo
6f7de19ed3 btrfs: quota: Set rescan progress to (u64)-1 if we hit last leaf
Commit ff3d27a048 ("btrfs: qgroup: Finish rescan when hit the last leaf
of extent tree") added a new exit for rescan finish.

However after finishing quota rescan, we set
fs_info->qgroup_rescan_progress to (u64)-1 before we exit through the
original exit path.
While we missed that assignment of (u64)-1 in the new exit path.

The end result is, the quota status item doesn't have the same value.
(-1 vs the last bytenr + 1)
Although it doesn't affect quota accounting, it's still better to keep
the original behavior.

Reported-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Fixes: ff3d27a048 ("btrfs: qgroup: Finish rescan when hit the last leaf of extent tree")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-06-28 11:30:48 +02:00
Linus Torvalds
84bfed40fc for-4.18-rc1-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAlsvtAIACgkQxWXV+ddt
 WDvPJQ//eEr+ACNxG5n42e63TaNpLOeoGAsUChwekP6DAIc2n/r78SHX+T/woDqd
 7/dc2eqlYF5Fmn6MPQ1ufL2xlfw0t3OnemK8T5+4sxZDdzeAH9V+kHaqoaLUPExL
 4r6lK5Ywwa2cWghC7WvQg3+bWLX18OEExG63SlEhLo3YJM5uUqVhGVPi6ARrbxNM
 GJvXcQsxjXLqukm4gYvHC6Zra9Awv65uiAU+VCm2y96j1fEJ0yjK/pC1RtoFGCqS
 48Jjuzfq/V3nxy0Wjr3DvpQVEQcKyGha6i/eazZISdRhGSjrYdvIwpUn7gZeoo2Q
 hT8VVergLbVYgIeaOwgwubQzNaG2C/ZTsEjPQrNrA7a/AGsh5C/ommYE9MSyS6L0
 PG0NLUNDXFmEj8WdI97So+1Sm2OCb04DPbPhHbbkhw5L/MPE1TaLN5aUWguj8laB
 NnyPRdVP9jCJAI0OhJY7nPDmsPKe2jogVVsRheTcob+V5G+vIgzDXlGfsW/88Seg
 dHubMaC0nz6u8Cj4dIviitiLXuustyz0JkVdljTLawWWJ/Hs7NlsSf3Q3nj2Kvia
 e8QMID0vLphQyL1hqC0n7M0g2ohq9NUGT1nhLTPSpFl0l8bIA9PQehOx9Q5vx8yp
 tJF+d0qiNfgvadA+KhyvQ8puQb2+zZQ8+Pqfjwd4ySD7SI5dcA4=
 =fCdm
 -----END PGP SIGNATURE-----

Merge tag 'for-4.18-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "Two regression fixes and an incorrect error value propagation fix from
  'rename exchange'"

* tag 'for-4.18-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  Btrfs: fix return value on rename exchange failure
  btrfs: fix invalid-free in btrfs_extent_same
  Btrfs: fix physical offset reported by fiemap for inline extents
2018-06-26 08:41:54 -07:00
Filipe Manana
c5b4a50b74 Btrfs: fix return value on rename exchange failure
If we failed during a rename exchange operation after starting/joining a
transaction, we would end up replacing the return value, stored in the
local 'ret' variable, with the return value from btrfs_end_transaction().
So this could end up returning 0 (success) to user space despite the
operation having failed and aborted the transaction, because if there are
multiple tasks having a reference on the transaction at the time
btrfs_end_transaction() is called by the rename exchange, that function
returns 0 (otherwise it returns -EIO and not the original error value).
So fix this by not overwriting the return value on error after getting
a transaction handle.

Fixes: cdd1fedf82 ("btrfs: add support for RENAME_EXCHANGE and RENAME_WHITEOUT")
CC: stable@vger.kernel.org # 4.9+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-06-22 12:59:08 +02:00
Lu Fengqi
22883ddc66 btrfs: fix invalid-free in btrfs_extent_same
If this condition ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
		   (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM))
is hit, we will go to free the uninitialized cmp.src_pages and
cmp.dst_pages.

Fixes: 67b07bd4be ("Btrfs: reuse cmp workspace in EXTENT_SAME ioctl")
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-06-21 19:21:13 +02:00
Filipe Manana
f098631848 Btrfs: fix physical offset reported by fiemap for inline extents
Commit 9d311e11fc ("Btrfs: fiemap: pass correct bytenr when
fm_extent_count is zero") introduced a regression where we no longer
report 0 as the physical offset for inline extents (and other extents
with a special block_start value). This is because it always sets the
variable used to report the physical offset ("disko") as em->block_start
plus some offset, and em->block_start has the value 18446744073709551614
((u64) -2) for inline extents.

This made the btrfs test 004 (from fstests) often fail, for example, for
a file with an inline extent we have the following items in the subvolume
tree:

    item 101 key (418 INODE_ITEM 0) itemoff 11029 itemsize 160
           generation 25 transid 38 size 1525 nbytes 1525
           block group 0 mode 100666 links 1 uid 0 gid 0 rdev 0
           sequence 0 flags 0x2(none)
           atime 1529342058.461891730 (2018-06-18 18:14:18)
           ctime 1529342058.461891730 (2018-06-18 18:14:18)
           mtime 1529342058.461891730 (2018-06-18 18:14:18)
           otime 1529342055.869892885 (2018-06-18 18:14:15)
    item 102 key (418 INODE_REF 264) itemoff 11016 itemsize 13
           index 25 namelen 3 name: fc7
    item 103 key (418 EXTENT_DATA 0) itemoff 9470 itemsize 1546
           generation 38 type 0 (inline)
           inline extent data size 1525 ram_bytes 1525 compression 0 (none)

Then when test 004 invoked fiemap against the file it got a non-zero
physical offset:

 $ filefrag -v /mnt/p0/d4/d7/fc7
 Filesystem type is: 9123683e
 File size of /mnt/p0/d4/d7/fc7 is 1525 (1 block of 4096 bytes)
  ext:     logical_offset:        physical_offset: length:   expected: flags:
    0:        0..    4095: 18446744073709551614..      4093:   4096:             last,not_aligned,inline,eof
 /mnt/p0/d4/d7/fc7: 1 extent found

This resulted in the test failing like this:

btrfs/004 49s ... [failed, exit status 1]- output mismatch (see /home/fdmanana/git/hub/xfstests/results//btrfs/004.out.bad)
    --- tests/btrfs/004.out	2016-08-23 10:17:35.027012095 +0100
    +++ /home/fdmanana/git/hub/xfstests/results//btrfs/004.out.bad	2018-06-18 18:15:02.385872155 +0100
    @@ -1,3 +1,10 @@
     QA output created by 004
     *** test backref walking
    -*** done
    +./tests/btrfs/004: line 227: [: 7.55578637259143e+22: integer expression expected
    +ERROR: 7.55578637259143e+22 is not a valid numeric value.
    +unexpected output from
    +	/home/fdmanana/git/hub/btrfs-progs/btrfs inspect-internal logical-resolve -s 65536 -P 7.55578637259143e+22 /home/fdmanana/btrfs-tests/scratch_1
    ...
    (Run 'diff -u tests/btrfs/004.out /home/fdmanana/git/hub/xfstests/results//btrfs/004.out.bad'  to see the entire diff)
Ran: btrfs/004

The large number in scientific notation reported as an invalid numeric
value is the result from the filter passed to perl which multiplies the
physical offset by the block size reported by fiemap.

So fix this by ensuring the physical offset is always set to 0 when we
are processing an extent with a special block_start value.

Fixes: 9d311e11fc ("Btrfs: fiemap: pass correct bytenr when fm_extent_count is zero")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-06-21 19:21:13 +02:00
Linus Torvalds
7a932516f5 vfs/y2038: inode timestamps conversion to timespec64
This is a late set of changes from Deepa Dinamani doing an automated
 treewide conversion of the inode and iattr structures from 'timespec'
 to 'timespec64', to push the conversion from the VFS layer into the
 individual file systems.
 
 There were no conflicts between this and the contents of linux-next
 until just before the merge window, when we saw multiple problems:
 
 - A minor conflict with my own y2038 fixes, which I could address
   by adding another patch on top here.
 - One semantic conflict with late changes to the NFS tree. I addressed
   this by merging Deepa's original branch on top of the changes that
   now got merged into mainline and making sure the merge commit includes
   the necessary changes as produced by coccinelle.
 - A trivial conflict against the removal of staging/lustre.
 - Multiple conflicts against the VFS changes in the overlayfs tree.
   These are still part of linux-next, but apparently this is no longer
   intended for 4.18 [1], so I am ignoring that part.
 
 As Deepa writes:
 
   The series aims to switch vfs timestamps to use struct timespec64.
   Currently vfs uses struct timespec, which is not y2038 safe.
 
   The series involves the following:
   1. Add vfs helper functions for supporting struct timepec64 timestamps.
   2. Cast prints of vfs timestamps to avoid warnings after the switch.
   3. Simplify code using vfs timestamps so that the actual
      replacement becomes easy.
   4. Convert vfs timestamps to use struct timespec64 using a script.
      This is a flag day patch.
 
   Next steps:
   1. Convert APIs that can handle timespec64, instead of converting
      timestamps at the boundaries.
   2. Update internal data structures to avoid timestamp conversions.
 
 Thomas Gleixner adds:
 
   I think there is no point to drag that out for the next merge window.
   The whole thing needs to be done in one go for the core changes which
   means that you're going to play that catchup game forever. Let's get
   over with it towards the end of the merge window.
 
 [1] https://www.spinics.net/lists/linux-fsdevel/msg128294.html
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJbInZAAAoJEGCrR//JCVInReoQAIlVIIMt5ZX6wmaKbrjy9Itf
 MfgbFihQ/djLnuSPVQ3nztcxF0d66BKHZ9puVjz6+mIHqfDvJTRwZs9nU+sOF/T1
 g78fRkM1cxq6ZCkGYAbzyjyo5aC4PnSMP/NQLmwqvi0MXqqrbDoq5ZdP9DHJw39h
 L9lD8FM/P7T29Fgp9tq/pT5l9X8VU8+s5KQG1uhB5hii4VL6pD6JyLElDita7rg+
 Z7/V7jkxIGEUWF7vGaiR1QTFzEtpUA/exDf9cnsf51OGtK/LJfQ0oiZPPuq3oA/E
 LSbt8YQQObc+dvfnGxwgxEg1k5WP5ekj/Wdibv/+rQKgGyLOTz6Q4xK6r8F2ahxs
 nyZQBdXqHhJYyKr1H1reUH3mrSgQbE5U5R1i3My0xV2dSn+vtK5vgF21v2Ku3A1G
 wJratdtF/kVBzSEQUhsYTw14Un+xhBLRWzcq0cELonqxaKvRQK9r92KHLIWNE7/v
 c0TmhFbkZA+zR8HdsaL3iYf1+0W/eYy8PcvepyldKNeW2pVk3CyvdTfY2Z87G2XK
 tIkK+BUWbG3drEGG3hxZ3757Ln3a9qWyC5ruD3mBVkuug/wekbI8PykYJS7Mx4s/
 WNXl0dAL0Eeu1M8uEJejRAe1Q3eXoMWZbvCYZc+wAm92pATfHVcKwPOh8P7NHlfy
 A3HkjIBrKW5AgQDxfgvm
 =CZX2
 -----END PGP SIGNATURE-----

Merge tag 'vfs-timespec64' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground

Pull inode timestamps conversion to timespec64 from Arnd Bergmann:
 "This is a late set of changes from Deepa Dinamani doing an automated
  treewide conversion of the inode and iattr structures from 'timespec'
  to 'timespec64', to push the conversion from the VFS layer into the
  individual file systems.

  As Deepa writes:

   'The series aims to switch vfs timestamps to use struct timespec64.
    Currently vfs uses struct timespec, which is not y2038 safe.

    The series involves the following:
    1. Add vfs helper functions for supporting struct timepec64
       timestamps.
    2. Cast prints of vfs timestamps to avoid warnings after the switch.
    3. Simplify code using vfs timestamps so that the actual replacement
       becomes easy.
    4. Convert vfs timestamps to use struct timespec64 using a script.
       This is a flag day patch.

    Next steps:
    1. Convert APIs that can handle timespec64, instead of converting
       timestamps at the boundaries.
    2. Update internal data structures to avoid timestamp conversions'

  Thomas Gleixner adds:

   'I think there is no point to drag that out for the next merge
    window. The whole thing needs to be done in one go for the core
    changes which means that you're going to play that catchup game
    forever. Let's get over with it towards the end of the merge window'"

* tag 'vfs-timespec64' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground:
  pstore: Remove bogus format string definition
  vfs: change inode times to use struct timespec64
  pstore: Convert internal records to timespec64
  udf: Simplify calls to udf_disk_stamp_to_time
  fs: nfs: get rid of memcpys for inode times
  ceph: make inode time prints to be long long
  lustre: Use long long type to print inode time
  fs: add timespec64_truncate()
2018-06-15 07:31:07 +09:00
Linus Torvalds
e7655d2b25 for-4.18-part2-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAlsg598ACgkQxWXV+ddt
 WDtG1w//R9/nvAk5A5cbForTXNyxwXAQnz0t2/4Lh5igbfJloqoTZtr47Gvqsvy+
 DITU+3BPcyupBuUFLoeivPC+ruKOUmle27Vm62mdZRtyt96kiUiV/m1gbPhFy8lW
 DKHK8tvtIoZObo5oNGvRxiuJPjefiChYZMDHokB+MY5ZALSRaIW9opj2WsM+ZAt7
 g9CEjeitQcBY68CCpSEVBlQSz+BTZYEDFJGNCmGDxGhaBGZr/ganrkDJ75cG6U10
 LnOZ6LDHNxGMqUm4wnhfmpHtVcIJiBF+gOyTumBPtFSoLnBverl684xizglpoq6d
 fnUP8Y6XR9JA4OCZvo310yvX9nyqgb0H2h+APO0f7jRRcJo0QSKZ/qZR+XZCk3PU
 91HtBopcGs8gGQUkRdAE7TMCiIEzL1eNOXHvsiILCObq1i7iNCe7Dzx6M6Gfgep8
 a3IcoVmSw1DFpln2ZxTQw9viAib41iU46XHXz7W7rGPulF5QdXGo5ScORRG6HBLE
 nZsXdTkrCPMJyN2bIhU6YJOK9rb9TjD4lUtnvzT8t1CfUsxQT4AsJykaYr9BwF2D
 Z4rBruUAQ3OmvXJDfGG4T5YCAdPBN+xBcxCeyrDZSD0r6YPQGoF0dlvHmvP0J78D
 oGkD1bb/gjcvsPJxtTQ4QWEh0oqZiDfRt4qdgO46vhba0onzQFw=
 =X2zA
 -----END PGP SIGNATURE-----

Merge tag 'for-4.18-part2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:

 - error handling fixup for one of the new ioctls from 1st pull

 - fix for device-replace that incorrectly uses inode pages and can mess
   up compressed extents in some cases

 - fiemap fix for reporting incorrect number of extents

 - vm_fault_t type conversion

* tag 'for-4.18-part2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: scrub: Don't use inode pages for device replace
  btrfs: change return type of btrfs_page_mkwrite to vm_fault_t
  Btrfs: fiemap: pass correct bytenr when fm_extent_count is zero
  btrfs: Check error of btrfs_iget in btrfs_search_path_in_tree_user
2018-06-15 07:23:00 +09:00
Arnd Bergmann
15eefe2a99 Merge branch 'vfs_timespec64' of https://github.com/deepa-hub/vfs into vfs-timespec64
Pull the timespec64 conversion from Deepa Dinamani:
 "The series aims to switch vfs timestamps to use
  struct timespec64. Currently vfs uses struct timespec,
  which is not y2038 safe.

  The flag patch applies cleanly. I've not seen the timestamps
  update logic change often. The series applies cleanly on 4.17-rc6
  and linux-next tip (top commit: next-20180517).

  I'm not sure how to merge this kind of a series with a flag patch.
  We are targeting 4.18 for this.
  Let me know if you have other suggestions.

  The series involves the following:
  1. Add vfs helper functions for supporting struct timepec64 timestamps.
  2. Cast prints of vfs timestamps to avoid warnings after the switch.
  3. Simplify code using vfs timestamps so that the actual
     replacement becomes easy.
  4. Convert vfs timestamps to use struct timespec64 using a script.
     This is a flag day patch.

  I've tried to keep the conversions with the script simple, to
  aid in the reviews. I've kept all the internal filesystem data
  structures and function signatures the same.

  Next steps:
  1. Convert APIs that can handle timespec64, instead of converting
     timestamps at the boundaries.
  2. Update internal data structures to avoid timestamp conversions."

I've pulled it into a branch based on top of the NFS changes that
are now in mainline, so I could resolve the non-obvious conflict
between the two while merging.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-06-14 14:54:00 +02:00
Kees Cook
6396bb2215 treewide: kzalloc() -> kcalloc()
The kzalloc() function has a 2-factor argument form, kcalloc(). This
patch replaces cases of:

        kzalloc(a * b, gfp)

with:
        kcalloc(a * b, gfp)

as well as handling cases of:

        kzalloc(a * b * c, gfp)

with:

        kzalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kzalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kzalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kzalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kzalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kzalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kzalloc
+ kcalloc
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kzalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kzalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kzalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kzalloc(sizeof(THING) * C2, ...)
|
  kzalloc(sizeof(TYPE) * C2, ...)
|
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(C1 * C2, ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Qu Wenruo
ac0b4145d6 btrfs: scrub: Don't use inode pages for device replace
[BUG]
Btrfs can create compressed extent without checksum (even though it
shouldn't), and if we then try to replace device containing such extent,
the result device will contain all the uncompressed data instead of the
compressed one.

Test case already submitted to fstests:
https://patchwork.kernel.org/patch/10442353/

[CAUSE]
When handling compressed extent without checksum, device replace will
goe into copy_nocow_pages() function.

In that function, btrfs will get all inodes referring to this data
extents and then use find_or_create_page() to get pages direct from that
inode.

The problem here is, pages directly from inode are always uncompressed.
And for compressed data extent, they mismatch with on-disk data.
Thus this leads to corrupted compressed data extent written to replace
device.

[FIX]
In this attempt, we could just remove the "optimization" branch, and let
unified scrub_pages() to handle it.

Although scrub_pages() won't bother reusing page cache, it will be a
little slower, but it does the correct csum checking and won't cause
such data corruption caused by "optimization".

Note about the fix: this is the minimal fix that can be backported to
older stable trees without conflicts. The whole callchain from
copy_nocow_pages() can be deleted, and will be in followup patches.

Fixes: ff023aac31 ("Btrfs: add code to scrub to copy read data to another disk")
CC: stable@vger.kernel.org # 4.4+
Reported-by: James Harvey <jamespharvey20@gmail.com>
Reviewed-by: James Harvey <jamespharvey20@gmail.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
[ remove code removal, add note why ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-06-11 15:59:14 +02:00
Souptick Joarder
a528a24150 btrfs: change return type of btrfs_page_mkwrite to vm_fault_t
Use the new return type vm_fault_t for fault handler. For now, this is
just documenting that the function returns a VM_FAULT value rather than
an errno. Once all instances are converted, vm_fault_t will become a
distinct type.

Reference commit 1c8f422059 ("mm: change return type to vm_fault_t")

vmf_error() is the newly introduced inline function in 4.17-rc6.

Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-06-07 17:27:45 +02:00
Robbie Ko
9d311e11fc Btrfs: fiemap: pass correct bytenr when fm_extent_count is zero
[BUG]
fm_mapped_extents is not correct when fm_extent_count is 0
Like:
   # mount /dev/vdb5 /mnt/btrfs
   # dd if=/dev/zero bs=16K count=4 oflag=dsync of=/mnt/btrfs/file
   # xfs_io -c "fiemap -v" /mnt/btrfs/file
   /mnt/btrfs/file:
   EXT: FILE-OFFSET      BLOCK-RANGE      TOTAL FLAGS
     0: [0..127]:        25088..25215       128   0x1

When user space wants to get the number of file extents,
set fm_extent_count to 0 to run fiemap and then read fm_mapped_extents.

In the above example, fiemap will return with fm_mapped_extents set to 4,
but it should be 1 since there's only one entry in the output.

[REASON]
The problem seems to be that disko is only set if
fieinfo->fi_extents_max is set. And this member is initialized, in the
generic ioctl_fiemap function, to the value of used-passed
fm_extent_count. So when the user passes 0 then fi_extent_max is also
set to zero and this causes btrfs to not initialize disko at all.
Eventually this leads emit_fiemap_extent being called with a bogus
'phys' argument preventing proper fiemap entries merging.

[FIX]
Move the disko initialization earlier in extent_fiemap making it
independent of user-passed arguments, allowing emit_fiemap_extent to
properly handle consecutive extent entries.

Signed-off-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-06-07 14:26:29 +02:00
Deepa Dinamani
95582b0083 vfs: change inode times to use struct timespec64
struct timespec is not y2038 safe. Transition vfs to use
y2038 safe struct timespec64 instead.

The change was made with the help of the following cocinelle
script. This catches about 80% of the changes.
All the header file and logic changes are included in the
first 5 rules. The rest are trivial substitutions.
I avoid changing any of the function signatures or any other
filesystem specific data structures to keep the patch simple
for review.

The script can be a little shorter by combining different cases.
But, this version was sufficient for my usecase.

virtual patch

@ depends on patch @
identifier now;
@@
- struct timespec
+ struct timespec64
  current_time ( ... )
  {
- struct timespec now = current_kernel_time();
+ struct timespec64 now = current_kernel_time64();
  ...
- return timespec_trunc(
+ return timespec64_trunc(
  ... );
  }

@ depends on patch @
identifier xtime;
@@
 struct \( iattr \| inode \| kstat \) {
 ...
-       struct timespec xtime;
+       struct timespec64 xtime;
 ...
 }

@ depends on patch @
identifier t;
@@
 struct inode_operations {
 ...
int (*update_time) (...,
-       struct timespec t,
+       struct timespec64 t,
...);
 ...
 }

@ depends on patch @
identifier t;
identifier fn_update_time =~ "update_time$";
@@
 fn_update_time (...,
- struct timespec *t,
+ struct timespec64 *t,
 ...) { ... }

@ depends on patch @
identifier t;
@@
lease_get_mtime( ... ,
- struct timespec *t
+ struct timespec64 *t
  ) { ... }

@te depends on patch forall@
identifier ts;
local idexpression struct inode *inode_node;
identifier i_xtime =~ "^i_[acm]time$";
identifier ia_xtime =~ "^ia_[acm]time$";
identifier fn_update_time =~ "update_time$";
identifier fn;
expression e, E3;
local idexpression struct inode *node1;
local idexpression struct inode *node2;
local idexpression struct iattr *attr1;
local idexpression struct iattr *attr2;
local idexpression struct iattr attr;
identifier i_xtime1 =~ "^i_[acm]time$";
identifier i_xtime2 =~ "^i_[acm]time$";
identifier ia_xtime1 =~ "^ia_[acm]time$";
identifier ia_xtime2 =~ "^ia_[acm]time$";
@@
(
(
- struct timespec ts;
+ struct timespec64 ts;
|
- struct timespec ts = current_time(inode_node);
+ struct timespec64 ts = current_time(inode_node);
)

<+... when != ts
(
- timespec_equal(&inode_node->i_xtime, &ts)
+ timespec64_equal(&inode_node->i_xtime, &ts)
|
- timespec_equal(&ts, &inode_node->i_xtime)
+ timespec64_equal(&ts, &inode_node->i_xtime)
|
- timespec_compare(&inode_node->i_xtime, &ts)
+ timespec64_compare(&inode_node->i_xtime, &ts)
|
- timespec_compare(&ts, &inode_node->i_xtime)
+ timespec64_compare(&ts, &inode_node->i_xtime)
|
ts = current_time(e)
|
fn_update_time(..., &ts,...)
|
inode_node->i_xtime = ts
|
node1->i_xtime = ts
|
ts = inode_node->i_xtime
|
<+... attr1->ia_xtime ...+> = ts
|
ts = attr1->ia_xtime
|
ts.tv_sec
|
ts.tv_nsec
|
btrfs_set_stack_timespec_sec(..., ts.tv_sec)
|
btrfs_set_stack_timespec_nsec(..., ts.tv_nsec)
|
- ts = timespec64_to_timespec(
+ ts =
...
-)
|
- ts = ktime_to_timespec(
+ ts = ktime_to_timespec64(
...)
|
- ts = E3
+ ts = timespec_to_timespec64(E3)
|
- ktime_get_real_ts(&ts)
+ ktime_get_real_ts64(&ts)
|
fn(...,
- ts
+ timespec64_to_timespec(ts)
,...)
)
...+>
(
<... when != ts
- return ts;
+ return timespec64_to_timespec(ts);
...>
)
|
- timespec_equal(&node1->i_xtime1, &node2->i_xtime2)
+ timespec64_equal(&node1->i_xtime2, &node2->i_xtime2)
|
- timespec_equal(&node1->i_xtime1, &attr2->ia_xtime2)
+ timespec64_equal(&node1->i_xtime2, &attr2->ia_xtime2)
|
- timespec_compare(&node1->i_xtime1, &node2->i_xtime2)
+ timespec64_compare(&node1->i_xtime1, &node2->i_xtime2)
|
node1->i_xtime1 =
- timespec_trunc(attr1->ia_xtime1,
+ timespec64_trunc(attr1->ia_xtime1,
...)
|
- attr1->ia_xtime1 = timespec_trunc(attr2->ia_xtime2,
+ attr1->ia_xtime1 =  timespec64_trunc(attr2->ia_xtime2,
...)
|
- ktime_get_real_ts(&attr1->ia_xtime1)
+ ktime_get_real_ts64(&attr1->ia_xtime1)
|
- ktime_get_real_ts(&attr.ia_xtime1)
+ ktime_get_real_ts64(&attr.ia_xtime1)
)

@ depends on patch @
struct inode *node;
struct iattr *attr;
identifier fn;
identifier i_xtime =~ "^i_[acm]time$";
identifier ia_xtime =~ "^ia_[acm]time$";
expression e;
@@
(
- fn(node->i_xtime);
+ fn(timespec64_to_timespec(node->i_xtime));
|
 fn(...,
- node->i_xtime);
+ timespec64_to_timespec(node->i_xtime));
|
- e = fn(attr->ia_xtime);
+ e = fn(timespec64_to_timespec(attr->ia_xtime));
)

@ depends on patch forall @
struct inode *node;
struct iattr *attr;
identifier i_xtime =~ "^i_[acm]time$";
identifier ia_xtime =~ "^ia_[acm]time$";
identifier fn;
@@
{
+ struct timespec ts;
<+...
(
+ ts = timespec64_to_timespec(node->i_xtime);
fn (...,
- &node->i_xtime,
+ &ts,
...);
|
+ ts = timespec64_to_timespec(attr->ia_xtime);
fn (...,
- &attr->ia_xtime,
+ &ts,
...);
)
...+>
}

@ depends on patch forall @
struct inode *node;
struct iattr *attr;
struct kstat *stat;
identifier ia_xtime =~ "^ia_[acm]time$";
identifier i_xtime =~ "^i_[acm]time$";
identifier xtime =~ "^[acm]time$";
identifier fn, ret;
@@
{
+ struct timespec ts;
<+...
(
+ ts = timespec64_to_timespec(node->i_xtime);
ret = fn (...,
- &node->i_xtime,
+ &ts,
...);
|
+ ts = timespec64_to_timespec(node->i_xtime);
ret = fn (...,
- &node->i_xtime);
+ &ts);
|
+ ts = timespec64_to_timespec(attr->ia_xtime);
ret = fn (...,
- &attr->ia_xtime,
+ &ts,
...);
|
+ ts = timespec64_to_timespec(attr->ia_xtime);
ret = fn (...,
- &attr->ia_xtime);
+ &ts);
|
+ ts = timespec64_to_timespec(stat->xtime);
ret = fn (...,
- &stat->xtime);
+ &ts);
)
...+>
}

@ depends on patch @
struct inode *node;
struct inode *node2;
identifier i_xtime1 =~ "^i_[acm]time$";
identifier i_xtime2 =~ "^i_[acm]time$";
identifier i_xtime3 =~ "^i_[acm]time$";
struct iattr *attrp;
struct iattr *attrp2;
struct iattr attr ;
identifier ia_xtime1 =~ "^ia_[acm]time$";
identifier ia_xtime2 =~ "^ia_[acm]time$";
struct kstat *stat;
struct kstat stat1;
struct timespec64 ts;
identifier xtime =~ "^[acmb]time$";
expression e;
@@
(
( node->i_xtime2 \| attrp->ia_xtime2 \| attr.ia_xtime2 \) = node->i_xtime1  ;
|
 node->i_xtime2 = \( node2->i_xtime1 \| timespec64_trunc(...) \);
|
 node->i_xtime2 = node->i_xtime1 = node->i_xtime3 = \(ts \| current_time(...) \);
|
 node->i_xtime1 = node->i_xtime3 = \(ts \| current_time(...) \);
|
 stat->xtime = node2->i_xtime1;
|
 stat1.xtime = node2->i_xtime1;
|
( node->i_xtime2 \| attrp->ia_xtime2 \) = attrp->ia_xtime1  ;
|
( attrp->ia_xtime1 \| attr.ia_xtime1 \) = attrp2->ia_xtime2;
|
- e = node->i_xtime1;
+ e = timespec64_to_timespec( node->i_xtime1 );
|
- e = attrp->ia_xtime1;
+ e = timespec64_to_timespec( attrp->ia_xtime1 );
|
node->i_xtime1 = current_time(...);
|
 node->i_xtime2 = node->i_xtime1 = node->i_xtime3 =
- e;
+ timespec_to_timespec64(e);
|
 node->i_xtime1 = node->i_xtime3 =
- e;
+ timespec_to_timespec64(e);
|
- node->i_xtime1 = e;
+ node->i_xtime1 = timespec_to_timespec64(e);
)

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: <anton@tuxera.com>
Cc: <balbi@kernel.org>
Cc: <bfields@fieldses.org>
Cc: <darrick.wong@oracle.com>
Cc: <dhowells@redhat.com>
Cc: <dsterba@suse.com>
Cc: <dwmw2@infradead.org>
Cc: <hch@lst.de>
Cc: <hirofumi@mail.parknet.co.jp>
Cc: <hubcap@omnibond.com>
Cc: <jack@suse.com>
Cc: <jaegeuk@kernel.org>
Cc: <jaharkes@cs.cmu.edu>
Cc: <jslaby@suse.com>
Cc: <keescook@chromium.org>
Cc: <mark@fasheh.com>
Cc: <miklos@szeredi.hu>
Cc: <nico@linaro.org>
Cc: <reiserfs-devel@vger.kernel.org>
Cc: <richard@nod.at>
Cc: <sage@redhat.com>
Cc: <sfrench@samba.org>
Cc: <swhiteho@redhat.com>
Cc: <tj@kernel.org>
Cc: <trond.myklebust@primarydata.com>
Cc: <tytso@mit.edu>
Cc: <viro@zeniv.linux.org.uk>
2018-06-05 16:57:31 -07:00
Misono Tomohiro
3ca57bd620 btrfs: Check error of btrfs_iget in btrfs_search_path_in_tree_user
The patch introducing the ioctl was not the latest version at the time
of merging to the mainline and needs a fixup from this patch.

Fixes: ba637a252d30 ("btrfs: Check error of btrfs_iget() in btrfs_search_path_in_tree_user")
Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-06-05 16:11:18 +02:00
Linus Torvalds
704996566f for-4.18-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAlsVV6wACgkQxWXV+ddt
 WDsaOhAAnrG3o/Bkn4loifYjiWQoArswwVJ2m5MvG14oPcn/c6wCUlE6mHdEsT8l
 WgltSRSd/3hJ1BcuWjhcR8RSLBRSaPcw4FAHikAdOWMrLXSKfA+quT/upXD00iDS
 +bnHoknc5vvk+Ow0KyGODAeMYfJm8gGB43BeVDr/mgrVRrwYY9r14s+6LX897NOT
 qObdxBjtedua0uIYZX5673siFaSbvJNQyGn6iKO9Ww+7bkWjgKO8qY8/3/gEaJn1
 q1303Oo65VOXQQKZed+NjPNakpqRmABaN79qTwWMnUI4qYBKi651a7sr5HljDpmc
 szY3uF/E7AOfJSDeTBdglFR1eQgv20ceeIx7FN0n6iUbuIVH9P85mBF6f76Hivpq
 fA39uPYxWwWq8RxmC09yqoTkuNS0zAQhov4n8XO0q/81Gfek0RpR+LMK15W02Ur8
 +5Pazkgz+xRYRPhpExe75pbM5N31KFJdf+4wpXeZoXKGTeiiCl/SZV3NzyUtemGg
 eN7ltHD/Y9iNpx7sgHn+2veXwn6psDad8ORxIlRyKDeot2pNZ4lnekPbqMC/IwAz
 hF3ZpcEo8v2Q2kqwCqw5evq4NSOvfG0cEuIqAKir1AgTn2nPH99qRSR1He9kluap
 GBPTPXNgBrhhdsh5kltI6CJcGE46bHsLG4LI5WvRs+wOtyaG5Ww=
 =jIvf
 -----END PGP SIGNATURE-----

Merge tag 'for-4.18-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs updates from David Sterba:
 "User visible features:

   - added support for the ioctl FS_IOC_FSGETXATTR, per-inode flags,
     successor of GET/SETFLAGS; now supports only existing flags:
     append, immutable, noatime, nodump, sync

   - 3 new unprivileged ioctls to allow users to enumerate subvolumes

   - dedupe syscall implementation does not restrict the range to 16MiB,
     though it still splits the whole range to 16MiB chunks

   - on user demand, rmdir() is able to delete an empty subvolume,
     export the capability in sysfs

   - fix inode number types in tracepoints, other cleanups

   - send: improved speed when dealing with a large removed directory,
     measurements show decrease from 2000 minutes to 2 minutes on a
     directory with 2 million entries

   - pre-commit check of superblock to detect a mysterious in-memory
     corruption

   - log message updates

  Other changes:

   - orphan inode cleanup improved, does no keep long-standing
     reservations that could lead up to early ENOSPC in some cases

   - slight improvement of handling snapshotted NOCOW files by avoiding
     some unnecessary tree searches

   - avoid OOM when dealing with many unmergeable small extents at flush
     time

   - speedup conversion of free space tree representations from/to
     bitmap/tree

   - code refactoring, deletion, cleanups:
      + delayed refs
      + delayed iput
      + redundant argument removals
      + memory barrier cleanups
      + remove a redundant mutex supposedly excluding several ioctls to
        run in parallel

   - new tracepoints for blockgroup manipulation

   - more sanity checks of compressed headers"

* tag 'for-4.18-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (183 commits)
  btrfs: Add unprivileged version of ino_lookup ioctl
  btrfs: Add unprivileged ioctl which returns subvolume's ROOT_REF
  btrfs: Add unprivileged ioctl which returns subvolume information
  Btrfs: clean up error handling in btrfs_truncate()
  btrfs: Factor out write portion of btrfs_get_blocks_direct
  btrfs: Factor out read portion of btrfs_get_blocks_direct
  btrfs: return ENOMEM if path allocation fails in btrfs_cross_ref_exist
  btrfs: raid56: Remove VLA usage
  btrfs: return error value if create_io_em failed in cow_file_range
  btrfs: drop useless member qgroup_reserved of btrfs_pending_snapshot
  btrfs: drop unused parameter qgroup_reserved
  btrfs: balance dirty metadata pages in btrfs_finish_ordered_io
  btrfs: lift some btrfs_cross_ref_exist checks in nocow path
  btrfs: Remove fs_info argument from btrfs_uuid_tree_rem
  btrfs: Remove fs_info argument from btrfs_uuid_tree_add
  Btrfs: remove unused check of skip_locking
  Btrfs: remove always true check in unlock_up
  Btrfs: grab write lock directly if write_lock_level is the max level
  Btrfs: move get root out of btrfs_search_slot to a helper
  Btrfs: use more straightforward extent_buffer_uptodate check
  ...
2018-06-04 14:29:13 -07:00
Linus Torvalds
f459c34538 for-4.18/block-20180603
-----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABCAAGBQJbFIrHAAoJEPfTWPspceCm2+kQAKo7o7HL30aRxJYu+gYafkuW
 PV47zr3e4vhMDEzDaMsh1+V7I7bm3uS+NZu6cFbcV+N9KXFpeb4V4Hvvm5cs+OC3
 WCOBi4eC1h4qnDQ3ZyySrCMN+KHYJ16pZqddEjqw+fhVudx8i+F+jz3Y4ZMDDc3q
 pArKZvjKh2wEuYXUMFTjaXY46IgPt+er94OwvrhyHk+4AcA+Q/oqSfSdDahUC8jb
 BVR3FV4I3NOHUaru0RbrUko13sVZSboWPCIFrlTDz8xXcJOnVHzdVS1WLFDXLHnB
 O8q9cADCfa4K08kz68RxykcJiNxNvz5ChDaG0KloCFO+q1tzYRoXLsfaxyuUDg57
 Zd93OFZC6hAzXdhclDFIuPET9OQIjDzwphodfKKmDsm3wtyOtydpA0o7JUEongp0
 O1gQsEfYOXmQsXlo8Ot+Z7Ne/HvtGZ91JahUa/59edxQbcKaMrktoyQsQ/d1nOEL
 4kXID18wPcFHWRQHYXyVuw6kbpRtQnh/U2m1eenSZ7tVQHwoe6mF3cfSf5MMseak
 k8nAnmsfEvOL4Ar9ftg61GOrImaQlidxOC2A8fmY5r0Sq/ZldvIFIZizsdTTCcni
 8SOTxcQowyqPf5NvMNQ8cKqqCJap3ppj4m7anZNhbypDIF2TmOWsEcXcMDn4y9on
 fax14DPLo59gBRiPCn5f
 =nga/
 -----END PGP SIGNATURE-----

Merge tag 'for-4.18/block-20180603' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:

 - clean up how we pass around gfp_t and
   blk_mq_req_flags_t (Christoph)

 - prepare us to defer scheduler attach (Christoph)

 - clean up drivers handling of bounce buffers (Christoph)

 - fix timeout handling corner cases (Christoph/Bart/Keith)

 - bcache fixes (Coly)

 - prep work for bcachefs and some block layer optimizations (Kent).

 - convert users of bio_sets to using embedded structs (Kent).

 - fixes for the BFQ io scheduler (Paolo/Davide/Filippo)

 - lightnvm fixes and improvements (Matias, with contributions from Hans
   and Javier)

 - adding discard throttling to blk-wbt (me)

 - sbitmap blk-mq-tag handling (me/Omar/Ming).

 - remove the sparc jsflash block driver, acked by DaveM.

 - Kyber scheduler improvement from Jianchao, making it more friendly
   wrt merging.

 - conversion of symbolic proc permissions to octal, from Joe Perches.
   Previously the block parts were a mix of both.

 - nbd fixes (Josef and Kevin Vigor)

 - unify how we handle the various kinds of timestamps that the block
   core and utility code uses (Omar)

 - three NVMe pull requests from Keith and Christoph, bringing AEN to
   feature completeness, file backed namespaces, cq/sq lock split, and
   various fixes

 - various little fixes and improvements all over the map

* tag 'for-4.18/block-20180603' of git://git.kernel.dk/linux-block: (196 commits)
  blk-mq: update nr_requests when switching to 'none' scheduler
  block: don't use blocking queue entered for recursive bio submits
  dm-crypt: fix warning in shutdown path
  lightnvm: pblk: take bitmap alloc. out of critical section
  lightnvm: pblk: kick writer on new flush points
  lightnvm: pblk: only try to recover lines with written smeta
  lightnvm: pblk: remove unnecessary bio_get/put
  lightnvm: pblk: add possibility to set write buffer size manually
  lightnvm: fix partial read error path
  lightnvm: proper error handling for pblk_bio_add_pages
  lightnvm: pblk: fix smeta write error path
  lightnvm: pblk: garbage collect lines with failed writes
  lightnvm: pblk: rework write error recovery path
  lightnvm: pblk: remove dead function
  lightnvm: pass flag on graceful teardown to targets
  lightnvm: pblk: check for chunk size before allocating it
  lightnvm: pblk: remove unnecessary argument
  lightnvm: pblk: remove unnecessary indirection
  lightnvm: pblk: return NVM_ error on failed submission
  lightnvm: pblk: warn in case of corrupted write buffer
  ...
2018-06-04 07:58:06 -07:00
Tomohiro Misono
23d0b79dfa btrfs: Add unprivileged version of ino_lookup ioctl
Add unprivileged version of ino_lookup ioctl BTRFS_IOC_INO_LOOKUP_USER
to allow normal users to call "btrfs subvolume list/show" etc. in
combination with BTRFS_IOC_GET_SUBVOL_INFO/BTRFS_IOC_GET_SUBVOL_ROOTREF.

This can be used like BTRFS_IOC_INO_LOOKUP but the argument is
different. This is  because it always searches the fs/file tree
correspoinding to the fd with which this ioctl is called and also
returns the name of bottom subvolume.

The main differences from original ino_lookup ioctl are:

  1. Read + Exec permission will be checked using inode_permission()
     during path construction. -EACCES will be returned in case
     of failure.
  2. Path construction will be stopped at the inode number which
     corresponds to the fd with which this ioctl is called. If
     constructed path does not exist under fd's inode, -EACCES
     will be returned.
  3. The name of bottom subvolume is also searched and filled.

Note that the maximum length of path is shorter 256 (BTRFS_VOL_NAME_MAX+1)
bytes than ino_lookup ioctl because of space of subvolume's name.

Reviewed-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Tested-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
[ style fixes ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-31 11:35:24 +02:00
Tomohiro Misono
42e4b520c8 btrfs: Add unprivileged ioctl which returns subvolume's ROOT_REF
Add unprivileged ioctl BTRFS_IOC_GET_SUBVOL_ROOTREF which returns
ROOT_REF information of the subvolume containing this inode except the
subvolume name (this is because to prevent potential name leak). The
subvolume name will be gained by user version of ino_lookup ioctl
(BTRFS_IOC_INO_LOOKUP_USER) which also performs permission check.

The min id of root ref's subvolume to be searched is specified by
@min_id in struct btrfs_ioctl_get_subvol_rootref_args. After the search
ends, @min_id is set to the last searched root ref's subvolid + 1. Also,
if there are more root refs than BTRFS_MAX_ROOTREF_BUFFER_NUM,
-EOVERFLOW is returned. Therefore the caller can just call this ioctl
again without changing the argument to continue search.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Tested-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
[ style fixes and struct item renames ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-31 11:35:23 +02:00
Tomohiro Misono
b64ec075bd btrfs: Add unprivileged ioctl which returns subvolume information
Add new unprivileged ioctl BTRFS_IOC_GET_SUBVOL_INFO which returns
the information of subvolume containing this inode.
(i.e. returns the information in ROOT_ITEM and ROOT_BACKREF.)

Reviewed-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Tested-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
[ minor style fixes, update struct comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-31 11:35:23 +02:00
Kent Overstreet
8ac9f7c1fd btrfs: convert to bioset_init()/mempool_init()
Convert btrfs to embedded bio sets.

Acked-by: Chris Mason <clm@fb.com>
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-30 15:33:32 -06:00
Omar Sandoval
ad7e1a740d Btrfs: clean up error handling in btrfs_truncate()
btrfs_truncate() uses two variables for error handling, ret and err (if
this sounds familiar, it's because btrfs_truncate_inode_items() did
something similar). This is error prone, as was made evident by "Btrfs:
fix error handling in btrfs_truncate()". We only have err because we
don't want to mask an error if we call btrfs_update_inode() and
btrfs_end_transaction(), so let's make that its own scoped return
variable and use ret everywhere else.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 21:27:32 +02:00
Nikolay Borisov
c5794e5178 btrfs: Factor out write portion of btrfs_get_blocks_direct
Now that the read side is extracted into its own function, do the same
to the write side. This leaves btrfs_get_blocks_direct_write with the
sole purpose of handling common locking required. Also flip the
condition in btrfs_get_blocks_direct_write so that the write case
comes first and we check for if (Create) rather than if (!create). This
is purely subjective but I believe makes reading a bit more "linear".
No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 19:01:44 +02:00
Nikolay Borisov
1c8d0175df btrfs: Factor out read portion of btrfs_get_blocks_direct
Currently this function handles both the READ and WRITE dio cases. This
is facilitated by a bunch of 'if' statements, a goto short-circuit
statement and a very perverse aliasing of "!created"(READ) case
by setting lockstart = lockend and checking for lockstart < lockend for
detecting the write. Let's simplify this mess by extracting the
READ-only code into a separate __btrfs_get_block_direct_read function.
This is only the first step, the next one will be to factor out the
write side as well. The end goal will be to have the common locking/
unlocking code in btrfs_get_blocks_direct and then it will call either
the read|write subvariants. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 19:01:43 +02:00
Su Yue
9132c4ff6f btrfs: return ENOMEM if path allocation fails in btrfs_cross_ref_exist
The error code does not match the reason of failure and may confuse the
callers.

Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 17:33:58 +02:00
Kees Cook
1389053e1b btrfs: raid56: Remove VLA usage
In the quest to remove all stack VLA usage from the kernel[1], this
allocates the working buffers during regular init, instead of using stack
space. This refactors the allocation code a bit to make it easier
to review.

[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 17:15:43 +02:00
Su Yue
090a127afa btrfs: return error value if create_io_em failed in cow_file_range
In cow_file_range(), create_io_em() may fail, but its return value is
not recorded.  Then return value may be 0 even it failed which is a
wrong behavior.

Let cow_file_range() return PTR_ERR(em) if create_io_em() failed.

Fixes: 6f9994dbab ("Btrfs: create a helper to create em for IO")
CC: stable@vger.kernel.org # 4.11+
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 16:51:08 +02:00
Gu JinXiang
6b0cb1f901 btrfs: drop useless member qgroup_reserved of btrfs_pending_snapshot
Since there is no more use of qgroup_reserved member in struct
btrfs_pending_snapshot, remove it.

Signed-off-by: Gu JinXiang <gujx@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 16:46:54 +02:00
Gu JinXiang
c4c129db5d btrfs: drop unused parameter qgroup_reserved
Since commit 7775c8184e ("btrfs: remove unused parameter from
btrfs_subvolume_release_metadata") parameter qgroup_reserved is not used
by caller of function btrfs_subvolume_reserve_metadata.  So remove it.

Signed-off-by: Gu JinXiang <gujx@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 16:46:53 +02:00
Ethan Lien
e73e81b6d0 btrfs: balance dirty metadata pages in btrfs_finish_ordered_io
[Problem description and how we fix it]
We should balance dirty metadata pages at the end of
btrfs_finish_ordered_io, since a small, unmergeable random write can
potentially produce dirty metadata which is multiple times larger than
the data itself. For example, a small, unmergeable 4KiB write may
produce:

    16KiB dirty leaf (and possibly 16KiB dirty node) in subvolume tree
    16KiB dirty leaf (and possibly 16KiB dirty node) in checksum tree
    16KiB dirty leaf (and possibly 16KiB dirty node) in extent tree

Although we do call balance dirty pages in write side, but in the
buffered write path, most metadata are dirtied only after we reach the
dirty background limit (which by far only counts dirty data pages) and
wakeup the flusher thread. If there are many small, unmergeable random
writes spread in a large btree, we'll find a burst of dirty pages
exceeds the dirty_bytes limit after we wakeup the flusher thread - which
is not what we expect. In our machine, it caused out-of-memory problem
since a page cannot be dropped if it is marked dirty.

Someone may worry about we may sleep in btrfs_btree_balance_dirty_nodelay,
but since we do btrfs_finish_ordered_io in a separate worker, it will not
stop the flusher consuming dirty pages. Also, we use different worker for
metadata writeback endio, sleep in btrfs_finish_ordered_io help us throttle
the size of dirty metadata pages.

[Reproduce steps]
To reproduce the problem, we need to do 4KiB write randomly spread in a
large btree. In our 2GiB RAM machine:

1) Create 4 subvolumes.
2) Run fio on each subvolume:

   [global]
   direct=0
   rw=randwrite
   ioengine=libaio
   bs=4k
   iodepth=16
   numjobs=1
   group_reporting
   size=128G
   runtime=1800
   norandommap
   time_based
   randrepeat=0

3) Take snapshot on each subvolume and repeat fio on existing files.
4) Repeat step (3) until we get large btrees.
   In our case, by observing btrfs_root_item->bytes_used, we have 2GiB of
   metadata in each subvolume tree and 12GiB of metadata in extent tree.
5) Stop all fio, take snapshot again, and wait until all delayed work is
   completed.
6) Start all fio. Few seconds later we hit OOM when the flusher starts
   to work.

It can be reproduced even when using nocow write.

Signed-off-by: Ethan Lien <ethanlien@synology.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 16:46:53 +02:00
Ethan Lien
78d4295b1e btrfs: lift some btrfs_cross_ref_exist checks in nocow path
In nocow path, we check if the extent is snapshotted in
btrfs_cross_ref_exist(). We can do the similar check earlier and avoid
unnecessary search into extent tree.

A fio test on a Intel D-1531, 16GB RAM, SSD RAID-5 machine as follows:

[global]
group_reporting
time_based
thread=1
ioengine=libaio
bs=4k
iodepth=32
size=64G
runtime=180
numjobs=8
rw=randwrite

[file1]
filename=/mnt/nocow/testfile

IOPS result:   unpatched     patched

1 fio round:     46670        46958
snapshot
2 fio round:     51826        54498
3 fio round:     59767        61289

After snapshot, the first fio get about 5% performance gain. As we
continually write to the same file, all writes will resume to nocow mode
and eventually we have no performance gain.

Signed-off-by: Ethan Lien <ethanlien@synology.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 16:46:53 +02:00
Lu Fengqi
d19577912d btrfs: Remove fs_info argument from btrfs_uuid_tree_rem
This function always takes a transaction handle which contains a
reference to the fs_info. Use that and remove the extra argument.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
[ rename the function ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 16:46:53 +02:00
Lu Fengqi
cdb345a877 btrfs: Remove fs_info argument from btrfs_uuid_tree_add
This function always takes a transaction handle which contains a
reference to the fs_info. Use that and remove the extra argument.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 16:46:52 +02:00
Liu Bo
f9ddfd0592 Btrfs: remove unused check of skip_locking
The check is superfluous since all callers who set search_for_commit
also have skip_locking set.

ASSERT() is put in place to ensure skip_locking is set by new callers.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 16:46:52 +02:00
Liu Bo
d80bb3f905 Btrfs: remove always true check in unlock_up
As unlock_up() is written as

for () {
   if (!path->locks[i])
       break;
   ...
   if (... && path->locks[i]) {
   }
}

Apparently, @path->locks[i] is always true at this 'if'.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 16:46:51 +02:00
Liu Bo
662c653bfd Btrfs: grab write lock directly if write_lock_level is the max level
Typically, when acquiring root node's lock, btrfs tries its best to get
read lock and trade for write lock if @write_lock_level implies to do so.

In case of (cow && (p->keep_locks || p->lowest_level)), write_lock_level
is set to BTRFS_MAX_LEVEL, which means we need to acquire root node's
write lock directly.

In this particular case, the dance of acquiring read lock and then trading
for write lock can be saved.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 16:46:51 +02:00
Liu Bo
1fc28d8e2e Btrfs: move get root out of btrfs_search_slot to a helper
It's good to have a helper instead of having all get-root details
open-coded.  The new helper locks (if necessary) and sets root node of
the path.

Also invert the checks to make the code flow easier to read.  There is
no functional change in this commit.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 16:46:44 +02:00
Liu Bo
e6a1d6fd27 Btrfs: use more straightforward extent_buffer_uptodate check
If parent_transid "0" is passed to btrfs_buffer_uptodate(),
btrfs_buffer_uptodate() is equivalent to extent_buffer_uptodate(), but
extent_buffer_uptodate() is preferred since we don't have to look into
verify_parent_transid().

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 16:46:44 +02:00
Liu Bo
ca19b4a699 Btrfs: remove superfluous free_extent_buffer in read_block_for_search
read_block_for_search() can be simplified as:

tmp = find_extent_buffer();
if (tmp)
   return;

...

free_extent_buffer();
read_tree_block();

Apparently, @tmp must be NULL at this point, free_extent_buffer() is not
needed.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 16:46:44 +02:00
Lu Fengqi
4ca6168327 btrfs: drop unused space_info parameter from create_space_info
Since commit dc2d3005d2 ("btrfs: remove dead create_space_info
calls"), there is only one caller btrfs_init_space_info. However, it
doesn't need create_space_info to return space_info at all.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 16:46:43 +02:00
Liu Bo
ff76a864cc Btrfs: add parent_transid parameter to veirfy_level_key
As verify_level_key() is checked after verify_parent_transid(), i.e.

if (verify_parent_transid())
   ret = -EIO;
else if (verify_level_key())
   ret = -EUCLEAN;

if parent_transid is 0, verify_parent_transid() skips verifying
parent_transid and considers eb as valid, and if verify_level_key()
reports something wrong, we're not going to know if it's caused by
corrupted metadata or non-checkecd eb (e.g. stale eb).

The stale eb can be from an outdated raid1 mirror after a degraded
mount, see eg "btrfs: fix reading stale metadata blocks after degraded
raid1 mounts" (02a3307aa9) for more details.

@parent_transid is able to tell whether the eb's generation has been
verified by the caller.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 16:46:43 +02:00
Qu Wenruo
9593bf4967 btrfs: qgroup: show more meaningful qgroup_rescan_init error message
Error message from qgroup_rescan_init() mostly looks like:

  BTRFS info (device nvme0n1p1): qgroup_rescan_init failed with -115

Which is far from meaningful, and sometimes confusing as for above
-EINPROGRESS it's mostly (despite the init race) harmless, but sometimes
it can also indicate problem if the return value is -EINVAL.

Change it to some more meaningful messages like:

  BTRFS info (device nvme0n1p1): qgroup rescan is already in progress

And

  BTRFS err(device nvme0n1p1): qgroup rescan init failed, qgroup is not enabled

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
[ update the messages and level ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 16:46:43 +02:00
Omar Sandoval
fd4e994bd1 Btrfs: fix memory and mount leak in btrfs_ioctl_rm_dev_v2()
If we have invalid flags set, when we error out we must drop our writer
counter and free the buffer we allocated for the arguments. This bug is
trivially reproduced with the following program on 4.7+:

	#include <fcntl.h>
	#include <stdint.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <unistd.h>
	#include <sys/ioctl.h>
	#include <sys/stat.h>
	#include <sys/types.h>
	#include <linux/btrfs.h>
	#include <linux/btrfs_tree.h>

	int main(int argc, char **argv)
	{
		struct btrfs_ioctl_vol_args_v2 vol_args = {
			.flags = UINT64_MAX,
		};
		int ret;
		int fd;

		if (argc != 2) {
			fprintf(stderr, "usage: %s PATH\n", argv[0]);
			return EXIT_FAILURE;
		}

		fd = open(argv[1], O_WRONLY);
		if (fd == -1) {
			perror("open");
			return EXIT_FAILURE;
		}

		ret = ioctl(fd, BTRFS_IOC_RM_DEV_V2, &vol_args);
		if (ret == -1)
			perror("ioctl");

		close(fd);
		return EXIT_SUCCESS;
	}

When unmounting the filesystem, we'll hit the
WARN_ON(mnt_get_writers(mnt)) in cleanup_mnt() and also may prevent the
filesystem to be remounted read-only as the writer count will stay
lifted.

Fixes: 6b526ed70c ("btrfs: introduce device delete by devid")
CC: stable@vger.kernel.org # 4.9+
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 16:46:43 +02:00
Qu Wenruo
de885e3ee2 btrfs: lzo: Harden inline lzo compressed extent decompression
For inlined extent, we only have one segment, thus less things to check.
And further more, inlined extent always has the csum in its leaf header,
it's less probable to have corrupted data.

Anyway, still check header and segment header.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 16:46:43 +02:00
Qu Wenruo
314bfa473b btrfs: lzo: Add header length check to avoid potential out-of-bounds access
James Harvey reported that some corrupted compressed extent data can
lead to various kernel memory corruption.

Such corrupted extent data belongs to inode with NODATASUM flags, thus
data csum won't help us detecting such bug.

If lucky enough, KASAN could catch it like:

BUG: KASAN: slab-out-of-bounds in lzo_decompress_bio+0x384/0x7a0 [btrfs]
Write of size 4096 at addr ffff8800606cb0f8 by task kworker/u16:0/2338

CPU: 3 PID: 2338 Comm: kworker/u16:0 Tainted: G           O      4.17.0-rc5-custom+ #50
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
Workqueue: btrfs-endio btrfs_endio_helper [btrfs]
Call Trace:
 dump_stack+0xc2/0x16b
 print_address_description+0x6a/0x270
 kasan_report+0x260/0x380
 memcpy+0x34/0x50
 lzo_decompress_bio+0x384/0x7a0 [btrfs]
 end_compressed_bio_read+0x99f/0x10b0 [btrfs]
 bio_endio+0x32e/0x640
 normal_work_helper+0x15a/0xea0 [btrfs]
 process_one_work+0x7e3/0x1470
 worker_thread+0x1b0/0x1170
 kthread+0x2db/0x390
 ret_from_fork+0x22/0x40
...

The offending compressed data has the following info:

Header:			length 32768		(looks completely valid)
Segment 0 Header:	length 3472882419	(obviously out of bounds)

Then when handling segment 0, since it's over the current page, we need
the copy the compressed data to temporary buffer in workspace, then such
large size would trigger out-of-bounds memory access, screwing up the
whole kernel.

Fix it by adding extra checks on header and segment headers to ensure we
won't access out-of-bounds, and even checks the decompressed data won't
be out-of-bounds.

Reported-by: James Harvey <jamespharvey20@gmail.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ updated comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-30 16:46:38 +02:00
Qu Wenruo
2a1f7c0cbd btrfs: lzo: document the compressed data format
Although it's not that complex, but such comment could still save
several minutes for newer reader/reviewer instead of inferring that from
the code.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor wording updates ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-29 18:13:00 +02:00
Qu Wenruo
d5c1d68fde btrfs: compression: Add linux/sizes.h for compression.h
Since compression.h is using the SZ_* macros, and if some file includes
only compression.h without linux/sizes.h, it will cause compile error.

One example is lzo.c, if it uses BTRFS_MAX_COMPRESSED.  Fix it by adding
linux/sizes.h in compression.h

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-29 18:13:00 +02:00
Omar Sandoval
b5c40d598f Btrfs: fix clone vs chattr NODATASUM race
In btrfs_clone_files(), we must check the NODATASUM flag while the
inodes are locked. Otherwise, it's possible that btrfs_ioctl_setflags()
will change the flags after we check and we can end up with a party
checksummed file.

The race window is only a few instructions in size, between the if and
the locks which is:

3834         if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
3835                 return -EISDIR;

where the setflags must be run and toggle the NODATASUM flag (provided
the file size is 0).  The clone will block on the inode lock, segflags
takes the inode lock, changes flags, releases log and clone continues.

Not impossible but still needs a lot of bad luck to hit unintentionally.

Fixes: 0e7b824c4e ("Btrfs: don't make a file partly checksummed through file clone")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-29 18:12:59 +02:00
Gu Jinxiang
b89311efe6 btrfs: propagate failures of __exclude_logged_extent to upper caller
Function btrfs_exclude_logged_extents may call __exclude_logged_extent
which may fail.
Propagate the failures of __exclude_logged_extent to upper caller.

Signed-off-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-29 18:12:58 +02:00
Nikolay Borisov
d4b20733d2 btrfs: Streamline shared ref check in alloc_reserved_tree_block
Instead of setting "parent" to ref->parent only when dealing with
a shared ref and subsequently performing another check to see
if (parent > 0), check the "node->type" directly and act accordingly.
This makes the code more streamline. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-29 18:12:57 +02:00
Nikolay Borisov
21ebfbe7e0 btrfs: Pass btrfs_delayed_extent_op to alloc_reserved_tree_block
Instead of taking only specific member of this structure, which results
in 2 extra arguments, just take the delayed_extent_op struct and
reference the arguments inside the functions. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-29 18:12:57 +02:00
Nikolay Borisov
4e6bd4e0aa btrfs: Simplify alloc_reserved_tree_block interface
This function currently takes 7 parameters, most of which are proxies
for values from btrfs_delayed_ref_node struct which is not passed. This
patch simplifies the interface of the function by simply passing said
delayed ref node struct to the function. This enables us to:

1. Move locals variables and init code related to them from
   run_delayed_tree_ref which should only be used inside
   alloc_reserved_tree_block, such as skinny_metadata and the btrfs_key,
   representing the extent being inserted. This removes the need for the
   "ins" argument. Instead, it's replaced by a local var with a more
   verbose name - extent_key.

2. Now that we have a reference to the node in alloc_reserved_tree_block
   the delayed_tree_ref struct can be referenced inside the function and
   this enable removing the "ref->level", "parent" and "ref_root"
   arguments.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-29 18:12:53 +02:00
Nikolay Borisov
9dcdbe0144 btrfs: Remove fs_info argument from alloc_reserved_tree_block
This function already takes a transaction handle which contains a
reference to the fs_info. So use this and remove the extra argument.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-29 18:12:53 +02:00
David Sterba
315b76b462 btrfs: tests: drop newline from test_msg strings
Now that test_err strings do not need the newline, remove them also from
the test_msg.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-29 18:12:52 +02:00
David Sterba
3c7251f2f8 btrfs: tests: add helper for error messages and update them
The test failures are not clearly visible in the system log as they're
printed at INFO level. Add a new helper that is level ERROR. As this
touches almost all strings, I took the opportunity to unify them:

- decapitalize the first letter as there's a prefix and the text
  continues after ":"
- glue strings split to more lines and un-indent so they fit to 80
  columns
- use %llu instead of %Lu
- drop \n from the modified messages (test_msg is left untouched)

Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-29 18:12:51 +02:00
Misono Tomohiro
ad1e3d5672 btrfs: use error code returned by btrfs_read_fs_root_no_name in search ioctl
btrfs_read_fs_root_no_name() may return ERR_PTR(-ENOENT) or
ERR_PTR(-ENOMEM) and therefore search_ioctl() and
btrfs_search_path_in_tree() should use PTR_ERR() instead of -ENOENT,
which all other callers of btrfs_read_fs_root_no_name() do.

Drop the error message as it would be confusing, the caller of ioctl
will likely interpret the error code and not look into the syslog.

Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:24:14 +02:00
Omar Sandoval
37becec95a Btrfs: allow empty subvol= again
I got a report that after upgrading to 4.16, someone's filesystems
weren't mounting:

[   23.845852] BTRFS info (device loop0): unrecognized mount option 'subvol='

Before 4.16, this mounted the default subvolume. It turns out that this
empty "subvol=" is actually an application bug, but it was causing the
application to fail, so it's an ABI break if you squint.

The generic parsing code we use for mount options (match_token())
doesn't match an empty string as "%s". Previously, setup_root_args()
removed the "subvol=" string, but the mount path was cleaned up to not
need that. Add a dummy Opt_subvol_empty to fix this.

The simple workaround is to use / or . for the value of 'subvol=' .

Fixes: 312c89fbca ("btrfs: cleanup btrfs_mount() using btrfs_mount_root()")
CC: stable@vger.kernel.org # 4.16+
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:24:13 +02:00
Anand Jain
b78e2b78a8 btrfs: fix describe_relocation when printing unknown flags
Looks like the original idea was to print the hex of the flags which is
not coded with their flag name. So use the current buf pointer bp
instead of buf.

Reaching the uknown flags should never happen, it's there just in case.

Fixes: ebce0e01b9 ("btrfs: make block group flags in balance printks human-readable")
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:24:11 +02:00
David Sterba
bf5091c8d6 btrfs: use kvzalloc for EXTENT_SAME temporary data
The dedupe range is 16 MiB, with 4 KiB pages and 8 byte pointers, the
arrays can be 32KiB large. To avoid allocation failures due to
fragmented memory, use the allocation with fallback to vmalloc.

The arrays are allocated and freed only inside btrfs_extent_same and
reused for all the ranges.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:24:09 +02:00
Timofey Titovets
67b07bd4be Btrfs: reuse cmp workspace in EXTENT_SAME ioctl
We support big dedup requests by splitting range to smaller parts, and
call dedupe logic on each of them.

Instead of repeated allocation and deallocation, allocate once at the
beginning and reuse in the iteration.

Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:24:07 +02:00
Timofey Titovets
b672876826 Btrfs: dedupe_file_range ioctl: remove 16MiB restriction
Currently btrfs_dedupe_file_range silently restricts the dedupe range to
to 16MiB to limit locking and working memory size and is documented in
manual page as implementation specific.

Let's remove that restriction by iterating over the dedup range in 16MiB
steps.  This is backward compatible and will not change anything for
requests smaller then 16MiB.

Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:24:04 +02:00
Timofey Titovets
3973909d92 Btrfs: split btrfs_extent_same
Split btrfs_extent_same() to two parts where one is the main EXTENT_SAME
entry and a helper that can be repeatedly called on a range.  This will
be used in following patches.

Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:24:03 +02:00
Omar Sandoval
399b0bbf5f Btrfs: reserve space for O_TMPFILE orphan item deletion
btrfs_link() calls btrfs_orphan_del() if it's linking an O_TMPFILE but
it doesn't reserve space to do so. Even before the removal of the
orphan_block_rsv it wasn't using it.

Fixes: ef3b9af50b ("Btrfs: implement inode_operations callback tmpfile")
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:24:00 +02:00
Omar Sandoval
7efc3e349c Btrfs: renumber BTRFS_INODE_ runtime flags and switch to enums
We got rid of BTRFS_INODE_HAS_ORPHAN_ITEM and
BTRFS_INODE_ORPHAN_META_RESERVED, so we can renumber the flags to make
them consecutive again.

Signed-off-by: Omar Sandoval <osandov@fb.com>
[ switch them enums so we don't have to do that again ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:59 +02:00
Omar Sandoval
a575ceeb13 Btrfs: get rid of unused orphan infrastructure
Now that we don't keep long-standing reservations for orphan items,
root->orphan_block_rsv isn't used. We can git rid of it, along with:

- root->orphan_lock, which was used to protect root->orphan_block_rsv
- root->orphan_inodes, which was used as a refcount for root->orphan_block_rsv
- BTRFS_INODE_ORPHAN_META_RESERVED, which was used to track reservations
  in root->orphan_block_rsv
- btrfs_orphan_commit_root(), which was the last user of any of these
  and does nothing else

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:57 +02:00
Omar Sandoval
27919067f1 Btrfs: fix ENOSPC caused by orphan items reservations
Currently, we keep space reserved for all inode orphan items until the
inode is evicted (i.e., all references to it are dropped). We hit an
issue where an application would keep a bunch of deleted files open (by
design) and thus keep a large amount of space reserved, causing ENOSPC
errors when other operations tried to reserve space. This long-standing
reservation isn't absolutely necessary for a couple of reasons:

- We can almost always make the reservation we need or steal from the
  global reserve for the orphan item
- If we can't, it's not the end of the world if we drop the orphan item
  on the floor and let the next mount clean it up

So, get rid of persistent reservation and just reserve space in
btrfs_evict_inode().

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:54 +02:00
Omar Sandoval
4b9d7b59bf Btrfs: refactor btrfs_evict_inode() reserve refill dance
The truncate loop in btrfs_evict_inode() does two things at once:

- It refills the temporary block reserve, potentially stealing from the
  global reserve or committing
- It calls btrfs_truncate_inode_items()

The tangle of continues hides the fact that these two steps are actually
separate. Split the first step out into a separate function both for
clarity and so that we can reuse it in a later patch.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:52 +02:00
Omar Sandoval
c08db7d8d2 Btrfs: don't return ino to ino cache if inode item removal fails
In btrfs_evict_inode(), if btrfs_truncate_inode_items() fails, the inode
item will still be in the tree but we still return the ino to the ino
cache. That will blow up later when someone tries to allocate that ino,
so don't return it to the cache.

Fixes: 581bb05094 ("Btrfs: Cache free inode numbers in memory")
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:51 +02:00
Omar Sandoval
05a5bd7c4d Btrfs: delete dead code in btrfs_orphan_commit_root()
btrfs_orphan_commit_root() tries to delete an orphan item for a
subvolume in the tree root, but we don't actually insert that item in
the first place. See commit 0a0d4415e3 ("Btrfs: delete dead code in
btrfs_orphan_add()"). We can get rid of it.

Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:49 +02:00
Omar Sandoval
7b40b695b4 Btrfs: get rid of BTRFS_INODE_HAS_ORPHAN_ITEM
Now that we don't add orphan items for truncate, there can't be races on
adding or deleting an orphan item, so this bit is unnecessary.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:48 +02:00
Omar Sandoval
f7e9e8fc79 Btrfs: stop creating orphan items for truncate
Currently, we insert an orphan item during a truncate so that if there's
a crash, we don't leak extents past the on-disk i_size. However, since
commit 7f4f6e0a3f ("Btrfs: only update disk_i_size as we remove
extents"), we keep disk_i_size in sync with the extent items as we
truncate, so orphan cleanup will never have any extents to remove. Don't
bother with the superfluous orphan item.

Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:46 +02:00
Omar Sandoval
0552210997 Btrfs: don't BUG_ON() in btrfs_truncate_inode_items()
btrfs_free_extent() can fail because of ENOMEM. There's no reason to
panic here, we can just abort the transaction.

Fixes: f4b9aa8d3b ("btrfs_truncate")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:45 +02:00
Omar Sandoval
fd86a3a315 Btrfs: fix error handling in btrfs_truncate_inode_items()
btrfs_truncate_inode_items() uses two variables for error handling, ret
and err. These are not handled consistently, leading to a couple of
bugs.

- Errors from btrfs_del_items() are handled but not propagated to the
  caller
- If btrfs_run_delayed_refs() fails and aborts the transaction, we
  continue running

Just use ret everywhere and simplify things a bit, fixing both of these
issues.

Fixes: 79787eaab4 ("btrfs: replace many BUG_ONs with proper error handling")
Fixes: 1262133b8d ("Btrfs: account for crcs in delayed ref processing")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:44 +02:00
Omar Sandoval
d1342aadbd Btrfs: update stale comments referencing vmtruncate()
Commit a41ad394a0 ("Btrfs: convert to the new truncate sequence")
changed btrfs_setsize() to call truncate_setsize() instead of
vmtruncate() but didn't update the comment above it. truncate_setsize()
never fails (the IS_SWAPFILE() check happens elsewhere), so remove the
comment.

Additionally, the comment above btrfs_page_mkwrite() references
vmtruncate(), but truncate_setsize() does the size write and page
locking now.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:43 +02:00
Nikolay Borisov
c442793e67 btrfs: Remove stale comment about select_delayed_ref
select_delayed_ref really just gets the next delayed ref which has to
be processed - either an add ref or drop ref. We never go back for
anything. So the comment is actually bogus, just remove it.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:42 +02:00
Misono Tomohiro
f902bd3a5e btrfs: sysfs: Add entry which shows if rmdir can work on subvolumes
Deletion of a subvolume by rmdir(2) has become allowed by the
'commit cd2decf640b1 ("btrfs: Allow rmdir(2) to delete an empty
subvolume")'.

It is a kind of new feature and this commits add a sysfs entry

  /sys/fs/btrfs/features/rmdir_subvol

to indicate the availability of the feature so that a user program
(e.g. fstests) can detect it.

Prior to this commit, all entries in /sys/fs/btrfs/features are feature
which depend on feature bits of superblock (i.e. each feature affects
on-disk format) and managed by attribute_group "btrfs_feature_attr_group".
For each fs, entries in /sys/fs/btrfs/UUID/features indicate which
features are enabled (or can be changed online) for the fs.

However, rmdir_subvol feature only depends on kernel module. Therefore
new attribute_group "btrfs_static_feature_attr_group" is introduced and
sysfs_merge_group() is used to share /sys/fs/btrfs/features directory.
Features in "btrfs_static_feature_attr_group" won't be listed in each
/sys/fs/btrfs/UUID/features.

Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:41 +02:00
Tomohiro Misono
6c52157fa9 btrfs: sysfs: Use enum/define value for feature array definitions
Use existing named values instead of the raw numbers.

Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:39 +02:00
Anand Jain
6dac13f8e2 btrfs: add prefix "balance:" for log messages
Kernel logs are very important for the forensic investigations of the
issues in general make it easy to use it. This patch adds 'balance:'
prefix so that it can be easily searched.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:38 +02:00
David Sterba
5c57b8b6a4 btrfs: unify naming of flags variables for SETFLAGS and XFLAGS
* The simple 'flags' refer to the btrfs inode
* ... that's in 'binode
* the FS_*_FL variables are 'fsflags'
* the old copies of the variable are prefixed by 'old_'
* Struct inode flags contain 'i_flags'.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:32 +02:00
David Sterba
025f212148 btrfs: add FS_IOC_FSSETXATTR ioctl
The new ioctl is an extension to the FS_IOC_SETFLAGS and adds new
flags and is extensible. Don't get fooled by the XATTR in the name, it
does not have anything in common with the extended attributes,
incidentally also abbreviated as XATTRs.

This patch allows to set the xflags portion of the fsxattr structure,
other items have no meaning and non-zero values will result in
EOPNOTSUPP.

Currently supported xflags:

- APPEND
- IMMUTABLE
- NOATIME
- NODUMP
- SYNC

The structure of btrfs_ioctl_fssetxattr copies btrfs_ioctl_setflags but
is simpler on the flag setting side.

The original patch was written by Chandan Jay Sharma but was incomplete
and no further revision has been sent.

Based-on-patches-by: Chandan Jay Sharma <chandansbg@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:31 +02:00
David Sterba
e4202ac927 btrfs: add FS_IOC_FSGETXATTR ioctl
The new ioctl is an extension to the FS_IOC_GETFLAGS and adds new
flags and is extensible. This patch allows to return the xflags portion
of the fsxattr structure, other items have no meaning for btrfs or can
be added later.

The original patch was written by Chandan Jay Sharma but was incomplete
and no further revision has been sent. Several cleanups were necessary
to avoid confusion with other ioctls, as we have another flavor of
flags.

Based-on-patches-by: Chandan Jay Sharma <chandansbg@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:29 +02:00
David Sterba
19f93b3cd8 btrfs: add helpers for FS_XFLAG_* conversion
Preparatory work for the FS_IOC_FSGETXATTR ioctl, basic conversions and
checking helpers.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:28 +02:00
David Sterba
a157d4fd81 btrfs: rename btrfs_flags_to_ioctl to reflect which flags it touches
Converts btrfs_inode::flags to the FS_*_FL flags.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:27 +02:00
David Sterba
5ba76abfb2 btrfs: rename check_flags to reflect which flags it touches
The FS_*_FL flags cannot be easily identified by a prefix but we still
need to recognize them so the 'fsflags' should be closer to the naming
scheme but again the 'fs' part sounds like it's a filesystem flag. I
don't have a better idea for now.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:25 +02:00
David Sterba
1905a0f7c7 btrfs: rename btrfs_mask_flags to reflect which flags it touches
The FS_*_FL flags cannot be easily identified by a variable name prefix
but we still need to recognize them so the 'fsflags' should be closer to
the naming scheme but again the 'fs' part sounds like it's a filesystem
flag. I don't have a better idea for now.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:24 +02:00
David Sterba
7b6a221e5b btrfs: rename btrfs_update_iflags to reflect which flags it touches
The btrfs inode flag flavour is now simply called 'inode flags' and the
vfs inode are i_flags.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:20 +02:00
Anand Jain
d9a071f008 btrfs: use common variable for fs_devices in btrfs_destroy_dev_replace_tgtdev
Use a local btrfs_fs_devices variable to access the structure.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:18 +02:00
Anand Jain
ab5c2f65de btrfs: drop uuid_mutex in btrfs_destroy_dev_replace_tgtdev
Delete the uuid_mutex lock here as this thread accesses the
btrfs_fs_devices::devices only (counters or called functions do a list
traversal). And the device_list_mutex lock is already taken.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:17 +02:00
Anand Jain
b25e59e2b2 btrfs: drop uuid_mutex in btrfs_dev_replace_finishing
btrfs_dev_replace_finishing updates devices (soruce and target) which
are within the btrfs_fs_devices::devices or withint the cloned seed
devices (btrfs_fs_devices::seed::devices), so we don't need the global
uuid_mutex.

The device replace context is also locked by its own locks.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:16 +02:00
Anand Jain
542c5908ab btrfs: replace uuid_mutex by device_list_mutex in btrfs_open_devices
btrfs_open_devices() is using the uuid_mutex, but as btrfs_open_devices
is just limited to openning all the devices under for given fsid, so we
don't need uuid_mutex.

Instead it should hold the device_list_mutex as it updates the members
of the btrfs_fs_devices and btrfs_device and not the whole fs_devs list.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:15 +02:00
Anand Jain
3dd0f7a364 btrfs: document uuid_mutex uasge in read_chunk_tree
read_chunk_tree() calls read_one_dev(), but for seed device we have
to search the fs_uuids list, so we need the uuid_mutex. Add a comment
comment, so that we can improve this part.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:14 +02:00
Anand Jain
41a52a0f1b btrfs: use existing cur_devices, cleanup btrfs_rm_device
Instead of de-referencing the device->fs_devices use cur_devices
which points to the same fs_devices and does not change.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:13 +02:00
Anand Jain
b6ed73bcb1 btrfs: reduce uuid_mutex critical section while scanning devices
The generic block device lookup or cleanup does not need the uuid mutex,
that's only for the device_list_add.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:12 +02:00
Nikolay Borisov
20a6800402 btrfs: Unexport and rename btrfs_invalidate_inodes
This function is no longer used outside of inode.c so just make it
static. At the same time give a more becoming name, since it's not
really invalidating the inodes but just calling d_prune_alias. Last,
but not least - move the function above the sole caller to avoid
introducing yet-another-pointless forward declaration.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:10 +02:00
David Sterba
093258e6eb btrfs: replace waitqueue_actvie with cond_wake_up
Use the wrappers and reduce the amount of low-level details about the
waitqueue management.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:09 +02:00
David Sterba
3d3a2e610e btrfs: add barriers to btrfs_sync_log before log_commit_wait wakeups
Currently the code assumes that there's an implied barrier by the
sequence of code preceding the wakeup, namely the mutex unlock.

As Nikolay pointed out:

I think this is wrong (not your code) but the original assumption that
the RELEASE semantics provided by mutex_unlock is sufficient.
According to memory-barriers.txt:

Section 'LOCK ACQUISITION FUNCTIONS' states:

 (2) RELEASE operation implication:

     Memory operations issued before the RELEASE will be completed before the
     RELEASE operation has completed.

     Memory operations issued after the RELEASE *may* be completed before the
     RELEASE operation has completed.

(I've bolded the may portion)

The example given there:

As an example, consider the following:

    *A = a;
    *B = b;
    ACQUIRE
    *C = c;
    *D = d;
    RELEASE
    *E = e;
    *F = f;

The following sequence of events is acceptable:

    ACQUIRE, {*F,*A}, *E, {*C,*D}, *B, RELEASE

So if we assume that *C is modifying the flag which the waitqueue is checking,
and *E is the actual wakeup, then those accesses can be re-ordered...

IMHO this code should be considered broken...
---

To be on the safe side, add the barriers. The synchronization logic
around log using the mutexes and several other threads does not make it
easy to reason for/against the barrier.

CC: Nikolay Borisov <nborisov@suse.com>
Link: https://lkml.kernel.org/r/6ee068d8-1a69-3728-00d1-d86293d43c9f@suse.com
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:06 +02:00
David Sterba
110a21feed btrfs: introduce conditional wakeup helpers
Add convenience wrappers for the waitqueue management that involves
memory barriers to prevent deadlocks. The helpers will let us remove
barriers and the necessary comments in several places.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:04 +02:00
Qu Wenruo
ff3d27a048 btrfs: qgroup: Finish rescan when hit the last leaf of extent tree
Under the following case, qgroup rescan can double account cowed tree
blocks:

In this case, extent tree only has one tree block.

-
| transid=5 last committed=4
| btrfs_qgroup_rescan_worker()
| |- btrfs_start_transaction()
| |  transid = 5
| |- qgroup_rescan_leaf()
|    |- btrfs_search_slot_for_read() on extent tree
|       Get the only extent tree block from commit root (transid = 4).
|       Scan it, set qgroup_rescan_progress to the last
|       EXTENT/META_ITEM + 1
|       now qgroup_rescan_progress = A + 1.
|
| fs tree get CoWed, new tree block is at A + 16K
| transid 5 get committed
-
| transid=6 last committed=5
| btrfs_qgroup_rescan_worker()
| btrfs_qgroup_rescan_worker()
| |- btrfs_start_transaction()
| |  transid = 5
| |- qgroup_rescan_leaf()
|    |- btrfs_search_slot_for_read() on extent tree
|       Get the only extent tree block from commit root (transid = 5).
|       scan it using qgroup_rescan_progress (A + 1).
|       found new tree block beyong A, and it's fs tree block,
|       account it to increase qgroup numbers.
-

In above case, tree block A, and tree block A + 16K get accounted twice,
while qgroup rescan should stop when it already reach the last leaf,
other than continue using its qgroup_rescan_progress.

Such case could happen by just looping btrfs/017 and with some
possibility it can hit such double qgroup accounting problem.

Fix it by checking the path to determine if we should finish qgroup
rescan, other than relying on next loop to exit.

Reported-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:23:03 +02:00
Qu Wenruo
b6debf15d4 btrfs: qgroup: Search commit root for rescan to avoid missing extent
When doing qgroup rescan using the following script (modified from
btrfs/017 test case), we can sometimes hit qgroup corruption.

------
umount $dev &> /dev/null
umount $mnt &> /dev/null

mkfs.btrfs -f -n 64k $dev
mount $dev $mnt

extent_size=8192

xfs_io -f -d -c "pwrite 0 $extent_size" $mnt/foo > /dev/null
btrfs subvolume snapshot $mnt $mnt/snap

xfs_io -f -c "reflink $mnt/foo" $mnt/foo-reflink > /dev/null
xfs_io -f -c "reflink $mnt/foo" $mnt/snap/foo-reflink > /dev/null
xfs_io -f -c "reflink $mnt/foo" $mnt/snap/foo-reflink2 > /dev/unll
btrfs quota enable $mnt

 # -W is the new option to only wait rescan while not starting new one
btrfs quota rescan -W $mnt
btrfs qgroup show -prce $mnt
umount $mnt

 # Need to patch btrfs-progs to report qgroup mismatch as error
btrfs check $dev || _fail
------

For fast machine, we can hit some corruption which missed accounting
tree blocks:
------
qgroupid         rfer         excl     max_rfer     max_excl parent  child
--------         ----         ----     --------     -------- ------  -----
0/5           8.00KiB        0.00B         none         none ---     ---
0/257         8.00KiB        0.00B         none         none ---     ---
------

This is due to the fact that we're always searching commit root for
btrfs_find_all_roots() at qgroup_rescan_leaf(), but the leaf we get is
from current transaction, not commit root.

And if our tree blocks get modified in current transaction, we won't
find any owner in commit root, thus causing the corruption.

Fix it by searching commit root for extent tree for
qgroup_rescan_leaf().

Reported-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:21:07 +02:00
Al Viro
7a1b1e7028 btrfs: take the last remnants of ->d_fsdata use out
[spotted while going through ->d_fsdata handling around d_splice_alias();
don't really care which tree that goes through]

The only thing even looking at ->d_fsdata in there (since 2012)
had been kfree(dentry->d_fsdata) in btrfs_dentry_delete().  Which,
incidentally, is all btrfs_dentry_delete() does.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:37 +02:00
Qu Wenruo
75cb857d26 btrfs: Do super block verification before writing it to disk
There are already 2 reports about strangely corrupted super blocks,
where csum still matches but extra garbage gets slipped into super block.

The corruption would looks like:
------
superblock: bytenr=65536, device=/dev/sdc1
---------------------------------------------------------
csum_type               41700 (INVALID)
csum                    0x3b252d3a [match]
bytenr                  65536
flags                   0x1
                        ( WRITTEN )
magic                   _BHRfS_M [match]
...
incompat_flags          0x5b22400000000169
                        ( MIXED_BACKREF |
                          COMPRESS_LZO |
                          BIG_METADATA |
                          EXTENDED_IREF |
                          SKINNY_METADATA |
                          unknown flag: 0x5b22400000000000 )
...
------
Or
------
superblock: bytenr=65536, device=/dev/mapper/x
---------------------------------------------------------
csum_type              35355 (INVALID)
csum_size              32
csum                   0xf0dbeddd [match]
bytenr                 65536
flags                  0x1
                       ( WRITTEN )
magic                  _BHRfS_M [match]
...
incompat_flags         0x176d200000000169
                       ( MIXED_BACKREF |
                         COMPRESS_LZO |
                         BIG_METADATA |
                         EXTENDED_IREF |
                         SKINNY_METADATA |
                         unknown flag: 0x176d200000000000 )
------

Obviously, csum_type and incompat_flags get some garbage, but its csum
still matches, which means kernel calculates the csum based on corrupted
super block memory.
And after manually fixing these values, the filesystem is completely
healthy without any problem exposed by btrfs check.

Although the cause is still unknown, at least detect it and prevent further
corruption.

Both reports have same symptoms, there's an overwrite on offset 192 of
the superblock, by 4 bytes. The superblock structure is not allocated or
freed and stays in the memory for the whole filesystem lifetime, so it's
not a use-after-free kind of error on someone else's leaked page.

As a vague point for the problable cause is mentioning of other system
freezing related to graphic card drivers.

Reported-by: Ken Swenson <flat@imo.uto.moe>
Reported-by: Ben Parsons <9parsonsb@gmail.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add brief analysis of the reports ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:36 +02:00
Qu Wenruo
069ec957c3 btrfs: Refactor btrfs_check_super_valid
Refactor btrfs_check_super_valid:

1) Rename it to btrfs_validate_mount_super()
   Now it's more obvious when the function should be called.

2) Extract core check routine into validate_super()
   Later write time check can reuse it, and if needed, we could also
   use validate_super() to check each super block.

3) Add more comments about btrfs_validate_mount_super()
   Mostly about what it doesn't check and when it should be called.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ rename to validate_super ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:36 +02:00
Qu Wenruo
21a852b018 btrfs: Move btrfs_check_super_valid() to avoid forward declaration
Move btrfs_check_super_valid() before its single caller to avoid forward
declaration.

Though such code motion is not recommended as it pollutes git history,
in this case the following patches would need to add new forward
declarations for static functions that we want to avoid.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:36 +02:00
Nikolay Borisov
ffa9a9ef2f btrfs: Remove fs_info argument from populate_free_space_tree
This function always takes a transaction handle which contains a
reference to the fs_info. Use that and remove the extra argument.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:36 +02:00
Nikolay Borisov
e7355e501d btrfs: Remove fs_info argument from add_to_free_space_tree
This function takes a transaction handle which already contains a
reference to the fs_info. So use it and remove the extra function
argument.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:36 +02:00
Nikolay Borisov
25a356d3f6 btrfs: Remove fs_info argument from remove_from_free_space_tree
This function alreay takes a transaction handle which holds a reference
to the fs_info. Use that and remove the extra argument.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:35 +02:00
Nikolay Borisov
c31683a6ef btrfs: Remove fs_info argument from __remove_from_free_space_tree
This function takes a transaction handle which holds a reference to
fs_info. So use that and remove the extra argument.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:35 +02:00
Nikolay Borisov
e581168d1f btrfs: Remove fs_info argument from remove_free_space_extent
This function takes a transaction handle which already has a reference
to the fs_info. Use it and remove the extra argument.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:35 +02:00
Nikolay Borisov
5cb1782213 btrfs: Remove fs_info argument from add_free_space_extent
This function always takes a transaction handle which references the
fs_info structure. So use that and remove the extra argument.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:35 +02:00
Nikolay Borisov
85a7ef130c btrfs: Remove fs_info argument from modify_free_space_bitmap
This function already takes a transaction which has a reference to the
fs_info. So use that and remove the extra argument.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:34 +02:00
Nikolay Borisov
690d76828a btrfs: Remove fs_info argument from update_free_space_extent_count
This function already takes a transaction handle which has a reference
to the fs_info. So use that and remove the extra argument.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:34 +02:00
Nikolay Borisov
5296c2bf51 btrfs: Remove fs_info parameter from convert_free_space_to_extents
This function always takes a transaction handle which contains a
reference to fs_info. So use that and kill the extra argument.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:34 +02:00
Nikolay Borisov
719fb4de55 btrfs: Remove fs_info argument from convert_free_space_to_bitmaps
This function already takes a transaction handle which contains a
reference to fs_info. So use that and remove the extra argument.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:34 +02:00
Nikolay Borisov
f3f7277995 btrfs: Remove fs_info parameter from remove_block_group_free_space
This function always takes a trans handle which contains a reference to
the fs_info. Use that and remove the extra argument.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:34 +02:00
Nikolay Borisov
4457c1c702 btrfs: Remove fs_info argument from add_new_free_space
This function also takes a btrfs_block_group_cache which contains a
referene to the fs_info. So use that and remove the extra argument.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:33 +02:00
Nikolay Borisov
66afee1848 btrfs: Remove fs_info parameter from add_new_free_space_info
This function already takes trans handle from where fs_info can be
referenced. Remove the redundant parameter.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:33 +02:00
Nikolay Borisov
2d5cffa1b0 btrfs: Remove fs_info argument from __add_to_free_space_tree
This function already takes a transaction handle which contains a
reference to fs_info.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:33 +02:00
Nikolay Borisov
9a7e0f9284 btrfs: Remove fs_info argument from __add_block_group_free_space
This function already takes a transaction handle which has a reference
to the fs_info.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:33 +02:00
Nikolay Borisov
e4e0711cd9 btrfs: Remove fs_info argument from add_block_group_free_space
We also pass in a transaction handle which has a reference to the
fs_info. Just remove the extraneous argument.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:33 +02:00
Nikolay Borisov
483bce068e btrfs: Make btrfs_init_dummy_trans initialize trans' fs_info field
This will be necessary for future cleanups which remove the fs_info
argument from some freespace tree functions.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:32 +02:00
Nikolay Borisov
7c8a0d363a btrfs: Add assert in __btrfs_del_delalloc_inode
The invariant is that when nr_delalloc_inodes is 0 then the root
mustn't have any inodes on its delalloc inodes list.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:32 +02:00
Robbie Ko
0f96f517dc btrfs: incremental send, improve rmdir performance for large directory
Currently when checking if a directory can be deleted, we always check
if all its children have been processed.

Example: A directory with 2,000,000 files was deleted

original: 1994m57.071s
patch:       1m38.554s

[FIX]
Instead of checking all children on all calls to can_rmdir(), we keep
track of the directory index offset of the child last checked in the
last call to can_rmdir(), and then use it as the starting point for
future calls to can_rmdir().

Signed-off-by: Robbie Ko <robbieko@synology.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:32 +02:00
Robbie Ko
35c8eda12f btrfs: incremental send, move allocation until it's needed in orphan_dir_info
Move the allocation after the search when it's clear that the new entry
will be added.

Signed-off-by: Robbie Ko <robbieko@synology.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:32 +02:00
Nikolay Borisov
2335efafa6 btrfs: split delayed ref head initialization and addition
add_delayed_ref_head really performed 2 independent operations -
initialisting the ref head and adding it to a list. Now that the init
part is in a separate function let's complete the separation between
both operations. This results in a lot simpler interface for
add_delayed_ref_head since the function now deals solely with either
adding the newly initialised delayed ref head or merging it into an
existing delayed ref head. This results in vastly simplified function
signature since 5 arguments are dropped. The only other thing worth
mentioning is that due to this split the WARN_ON catching reinit of
existing. In this patch the condition is extended such that:

  qrecord && head_ref->qgroup_ref_root && head_ref->qgroup_reserved

is added. This is done because the two qgroup_* prefixed member are
set only if both ref_root and reserved are passed. So functionally
it's equivalent to the old WARN_ON and allows to remove the two args
from add_delayed_ref_head.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:32 +02:00
Nikolay Borisov
eb86ec73b9 btrfs: Use init_delayed_ref_head in add_delayed_ref_head
Use the newly introduced function when initialising the head_ref in
add_delayed_ref_head. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:31 +02:00
Nikolay Borisov
a2e569b3f2 btrfs: Introduce init_delayed_ref_head
add_delayed_ref_head implements the logic to both initialize a head_ref
structure as well as perform the necessary operations to add it to the
delayed ref machinery. This has resulted in a very cumebrsome interface
with loads of parameters and code, which at first glance, looks very
unwieldy. Begin untangling it by first extracting the initialization
only code in its own function. It's more or less verbatim copy of the
first part of add_delayed_ref_head.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:31 +02:00
Nikolay Borisov
cd7f9699b1 btrfs: Open-code add_delayed_data_ref
Now that the initialization part and the critical section code have been
split it's a lot easier to open code add_delayed_data_ref. Do so in the
following manner:

1. The common init function is put immediately after memory-to-be-initialized
   is allocated, followed by the specific data ref initialization.

2. The only piece of code that remains in the critical section is
   insert_delayed_ref call.

3. Tracing and memory freeing code is moved outside of the critical
   section.

No functional changes, just an overall shorter critical section.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:31 +02:00
Nikolay Borisov
70d640004a btrfs: Open-code add_delayed_tree_ref
Now that the initialization part and the critical section code have been
split it's a lot easier to open code add_delayed_tree_ref. Do so in the
following manner:

1. The comming init code is put immediately after memory-to-be-initialized
   is allocated, followed by the ref-specific member initialization.

2. The only piece of code that remains in the critical section is
   insert_delayed_ref call.

3. Tracing and memory freeing code is put outside of the critical
   section as well.

The only real change here is an overall shorter critical section when
dealing with delayed tree refs. From functional point of view - the code
is unchanged.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:31 +02:00
Nikolay Borisov
c812c8a857 btrfs: Use init_delayed_ref_common in add_delayed_data_ref
Use the newly introduced helper and remove the duplicate code.  No
functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:31 +02:00
Nikolay Borisov
646f4dd76f btrfs: Use init_delayed_ref_common in add_delayed_tree_ref
Use the newly introduced common helper.  No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:30 +02:00
Nikolay Borisov
cb49a87b2a btrfs: Factor out common delayed refs init code
THe majority of the init code for struct btrfs_delayed_ref_node is
duplicated in add_delayed_data_ref and add_delayed_tree_ref. Factor out
the common bits in init_delayed_ref_common. This function is going to be
used in future patches to clean that up. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:30 +02:00
Chengguang Xu
891f41cb27 btrfs: return original error code when failing from option parsing
It's not good to overwrite -ENOMEM using -EINVAL when failing from mount
option parsing, so just return original error code.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:30 +02:00
David Sterba
6fcf6e2bff btrfs: remove redundant btrfs_balance_control::fs_info
The fs_info is always available from the context so we don't need to
store it in the structure.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:30 +02:00
Qu Wenruo
c9f6f3cd1c btrfs: qgroup: Allow trace_btrfs_qgroup_account_extent() to record its transid
When debugging quota rescan race, some times btrfs rescan could account
some old (committed) leaf and then re-account newly committed leaf
in next generation.

This race needs extra transid to locate, so add @transid for
trace_btrfs_qgroup_account_extent() for such debug.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:30 +02:00
Colin Ian King
f5686e3acd btrfs: send: fix spelling mistake: "send_in_progres" -> "send_in_progress"
Trivial fix to spelling mistake of function name in btrfs_err message

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:29 +02:00
Nikolay Borisov
63a9c7b9ce btrfs: Remove devid parameter from btrfs_rmap_block
This function is used in only one place and devid argument is always
passed 0. So just remove it, similarly to how it was removed in the
userspace code.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:29 +02:00
Qu Wenruo
8b317901da btrfs: trace: Allow trace_qgroup_update_counters() to record old rfer/excl value
Origin trace_qgroup_update_counters() only records qgroup id and its
reference count change.

It's good enough to debug qgroup accounting change, but when rescan race
is involved, it's pretty hard to distinguish which modification belongs
to which rescan.

So add old_rfer and old_excl trace output to help distinguishing
different rescan instance.
(Different rescan instance should reset its qgroup->rfer to 0)

For trace event parameter, it just changes from u64 qgroup_id to struct
btrfs_qgroup *qgroup, so number of parameters is not changed at all.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:29 +02:00
Nikolay Borisov
3a2f8c07e1 btrfs: Unexport btrfs_alloc_delalloc_work
It's used only in inode.c so makes no sense to have it exported. Also
move the definition of btrfs_delalloc_work to inode.c since it's used
only this file.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:29 +02:00
Nikolay Borisov
076da91cd9 btrfs: Remove delayed_iput member from btrfs_delalloc_work
When allocating a delalloc work we are always setting the delayed_iput
to 0. So remove the delay_iput member of btrfs_delalloc_work, as a
result also remove it as a parameter from btrfs_alloc_delalloc_work
since it's not used anymore.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:29 +02:00
Nikolay Borisov
4fbb514785 btrfs: Remove delay_iput parameter from __start_delalloc_inodes
It's always set to 0 so remove it.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
[ rename to start_delalloc_inodes ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:28 +02:00
Nikolay Borisov
76f32e240e btrfs: Remove delayed_iput parameter from btrfs_start_delalloc_inodes
It's always set to 0, so just remove it and collapse the constant value
to the only function we are passing it.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:28 +02:00
Nikolay Borisov
82b3e53b8d btrfs: Remove delayed_iput parameter of btrfs_start_delalloc_roots
This parameter was introduced alongside the function in
eb73c1b7ce ("Btrfs: introduce per-subvolume delalloc inode list") to
avoid deadlocks since this function was used in the transaction commit
path. However, commit 8d875f95da ("btrfs: disable strict file flushes
for renames and truncates") removed that usage, rendering the parameter
obsolete.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:28 +02:00
Gu Jinxiang
0338dff6e0 btrfs: do reverse path readahead in btrfs_shrink_device
In btrfs_shrink_device, before btrfs_search_slot, path->reada is set to
READA_FORWARD. But I think READA_BACK is correct.

Since:

 1. key.offset is set to (u64)-1
 2. after btrfs_search_slot, btrfs_previous_item is called

So, for readahead previous items, READA_BACK is the correct one.

Signed-off-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:28 +02:00
Qu Wenruo
4ed0a7a3b7 btrfs: trace: Add trace points for unused block groups
This patch will add the following trace events:
1) btrfs_remove_block_group
   For btrfs_remove_block_group() function.
   Triggered when a block group is really removed.

2) btrfs_add_unused_block_group
   Triggered which block group is added to unused_bgs list.

3) btrfs_skip_unused_block_group
   Triggered which unused block group is not deleted.

These trace events is pretty handy to debug case related to block group
auto remove.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:28 +02:00
Qu Wenruo
3dca5c942d btrfs: trace: Remove unnecessary fs_info parameter for btrfs__reserve_extent event class
fs_info can be extracted from btrfs_block_group_cache, and all
btrfs_block_group_cache is created by btrfs_create_block_group_cache()
with fs_info initialized, no need to worry about NULL pointer
dereference.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:27 +02:00
Gu Jinxiang
9113493e3a btrfs: remove unused fs_info parameter
Since the commit c6100a4b4e ("Btrfs: replace tree->mapping with
tree->private_data"), parameter fs_info in alloc_reloc_control is
not used. So remove it.

Signed-off-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:27 +02:00
Anand Jain
f9fbcaa2a3 btrfs: move btrfs_raid_mindev_errorvalues to btrfs_raid_attr table
Add a new member struct btrfs_raid_attr::mindev_error so that
btrfs_raid_array can maintain the error code to return if the minimum
number of devices condition is not met while trying to delete a device
in the given raid. And so we can drop btrfs_raid_mindev_error.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:27 +02:00
Anand Jain
41a6e8913c btrfs: move btrfs_raid_group values to btrfs_raid_attr table
Add a new member struct btrfs_raid_attr::bg_flag so that
btrfs_raid_array can maintain the bit map flag of the raid type, and
so we can drop btrfs_raid_group.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:27 +02:00
Anand Jain
ed23467b18 btrfs: move btrfs_raid_type_names values to btrfs_raid_attr table
Add a new member struct btrfs_raid_attr::raid_name so that
btrfs_raid_array can maintain the name of the raid type, and so we can
drop btrfs_raid_type_names.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:27 +02:00
Qu Wenruo
b545993694 btrfs: print-tree: Add eb locking status output for debug build
It's pretty handy if we can get the debug output for locking status of
an extent buffer, specially for race condition related debugging.

So add the following output for btrfs_print_tree() and
btrfs_print_leaf():
- refs
- write_locks (as w:%d)
- read_locks (as r:%d)
- blocking_writers (as bw:%d)
- blocking_readers (as br:%d)
- spinning_writers (as sw:%d)
- spinning_readers (as sr:%d)
- lock_owner
- current->pid

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:26 +02:00
David Sterba
833aae18fc btrfs: open code set_balance_control
The helper is quite simple and I'd like to see the locking in the
caller.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:26 +02:00
David Sterba
1354e1a13e btrfs: use mutex in btrfs_resume_balance_async
While the spinlock does not cause problems, using the mutex is more
correct and consistent with others. The global status of balance is eg.
checked from btrfs_pause_balance or btrfs_cancel_balance with mutex.

Resuming balance happens during mount or ro->rw remount. In the former
case, no other user of the balance_ctl exists, in the latter, balance
cannot run until the ro/rw transition is finished.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:26 +02:00
David Sterba
008ef0969d btrfs: drop lock parameter from update_ioctl_balance_args and rename
The parameter controls locking of the stats part but we can lock it
unconditionally, as this only happens once when balance starts. This is
not performance critical.

Add the prefix for an exported function.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:26 +02:00
David Sterba
cf7d20f447 btrfs: move and comment read-only check in btrfs_cancel_balance
Balance cannot be started on a read-only filesystem and will have to
finish/exit before eg. going to read-only via remount.

In case the filesystem is forcibly set to read-only after an error,
balance will finish anyway and if the cancel call is too fast it will
just wait for that to happen.

The last case is when the balance is paused after mount but it's
read-only and cancelling would want to delete the item. The test is
moved after the check if balance is running at all, as it looks more
logical to report "no balance running" instead of "read-only
filesystem".

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:26 +02:00
David Sterba
3009a62f3b btrfs: track running balance in a simpler way
Currently fs_info::balance_running is 0 or 1 and does not use the
semantics of atomics. The pause and cancel check for 0, that can happen
only after __btrfs_balance exits for whatever reason.

Parallel calls to balance ioctl may enter btrfs_ioctl_balance multiple
times but will block on the balance_mutex that protects the
fs_info::flags bit.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:25 +02:00
David Sterba
dccdb07bc9 btrfs: kill btrfs_fs_info::volume_mutex
Mutual exclusion of device add/rm and balance was done by the volume
mutex up to version 3.7. The commit 5ac00addc7 ("Btrfs: disallow
mutually exclusive admin operations from user mode") added a bit that
essentially tracked the same information.

The status bit has an advantage over a mutex that it can be set without
restrictions of function context, so it started to be used in the
mount-time resuming of balance or device replace.

But we don't really need to track the same information in two ways.

1) After the previous cleanups, the main ioctl handlers for
   add/del/resize copy the EXCL_OP bit next to the volume mutex, here
   it's clearly safe.

2) Resuming balance during mount or after rw remount will set only the
   EXCL_OP bit and the volume_mutex is held in the kernel thread that
   calls btrfs_balance.

3) Resuming device replace during mount or after rw remount is done
   after balance and is excluded by the EXCL_OP bit. It does not take
   the volume_mutex at all and completely relies on the EXCL_OP bit.

4) The resuming of balance and dev-replace cannot hapen at the same time
   as the ioctls cannot be started in parallel. Nevertheless, a crafted
   image could trigger that and a warning is printed.

5) Balance is normally excluded by EXCL_OP and also uses own mutex to
   protect against concurrent access to its status data. There's some
   trickery to maintain the right lock nesting in case we need to
   reexamine the status in btrfs_ioctl_balance. The volume_mutex is
   removed and the unlock/lock sequence is left in place as we might
   expect other waiters to proceed.

6) Similar to 5, the unlock/lock sequence is kept in
   btrfs_cancel_balance to allow waiters to continue.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:25 +02:00
David Sterba
a0fecc2371 btrfs: remove wrong use of volume_mutex from btrfs_dev_replace_start
The volume mutex does not protect against anything in this case, the
comment about scrub is right but not related to locking and looks
confusing. The comment in btrfs_find_device_missing_or_by_path is wrong
and confusing too.

The device_list_mutex is not held here to protect device lookup, but in
this case device replace cannot run in parallel with device removal (due
to exclusive op protection), so we don't need further locking here.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:25 +02:00
David Sterba
149196a2ae btrfs: cleanup helpers that reset balance state
The function __cancel_balance name is confusing with the cancel
operation of balance and it really resets the state of balance back to
zero. The unset_balance_control helper is called only from one place and
simple enough to be inlined.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:25 +02:00
David Sterba
eee95e3fb0 btrfs: add sanity check when resuming balance after mount
Replace a WARN_ON with a proper check and message in case something goes
really wrong and resumed balance cannot set up its exclusive status.
The check is a user friendly assertion, I don't expect to ever happen
under normal circumstances.

Also document that the paused balance starts here and owns the exclusive
op status.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:25 +02:00
David Sterba
010a47bde9 btrfs: add proper safety check before resuming dev-replace
The device replace is paused by unmount or read only remount, and
resumed on next mount or write remount.

The exclusive status should be checked properly as it's a global
invariant and we must not allow 2 operations run. In this case, the
balance can be also paused and resumed under same conditions. It's
always checked first so dev-replace could see the EXCL_OP already taken,
BUT, the ioctl would never let start both at the same time.

Replace the WARN_ON with message and return 0, indicating no error as
this is purely theoretical and the user will be informed. Resolving that
manually should be possible by waiting for the other operation to finish
or cancel the paused state.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:24 +02:00
David Sterba
a17c95df4c btrfs: move clearing of EXCL_OP out of __cancel_balance
Make the clearning visible in the callers so we can pair it with the
test_and_set part.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:24 +02:00
David Sterba
72b81abf95 btrfs: move volume_mutex to callers of btrfs_rm_device
Move locking and unlocking next to the BTRFS_FS_EXCL_OP bit manipulation
so it's obvious that the two happen at the same time.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:24 +02:00
David Sterba
d48f39d5a5 btrfs: move btrfs_init_dev_replace_tgtdev to dev-replace.c and make static
The function logically belongs there and there's only a single caller,
no need to export it. No code changes.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:24 +02:00
David Sterba
a425f9d475 btrfs: export and rename free_device
The function will be used outside of volumes.c, the allocation
btrfs_alloc_device is also exported.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:23 +02:00
David Sterba
6fc4749d25 btrfs: make success path out of btrfs_init_dev_replace_tgtdev more clear
This is a preparatory cleanup that will make clear that the only
successful way out of btrfs_init_dev_replace_tgtdev will also set the
device_out to a valid pointer. With this guarantee, the callers can be
simplified.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:23 +02:00
David Sterba
00251a527a btrfs: squeeze btrfs_dev_replace_continue_on_mount to its caller
The function is called once and is fairly small, we can merge it with
the caller.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:22 +02:00
Anand Jain
b518519713 btrfs: cleanup btrfs_rm_device() promote fs_devices pointer
This function uses fs_info::fs_devices number of time, however we
declare and use it only at the end, instead do it in the beginning of
the function and use it.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:22 +02:00
Anand Jain
636d2c9d63 btrfs: cleanup find_device() drop list_head pointer
find_device() declares struct list_head *head pointer and used only once,
instead just use it directly.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:22 +02:00
Anand Jain
897fb5734a btrfs: rename __btrfs_open_devices to open_fs_devices
__btrfs_open_devices() is un-exported drop __ prefix and rename it to
open_fs_devices().

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:21 +02:00
Anand Jain
0226e0eb65 btrfs: rename __btrfs_close_devices to close_fs_devices
__btrfs_close_devices() is un-exported, drop the __ prefix and rename it
to close_fs_devices().

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:21 +02:00
Anand Jain
f117e290e8 btrfs: cleanup __btrfs_open_devices() drop head pointer
__btrfs_open_devices() declares struct list_head *head, however head is
used only once, instead use btrfs_fs_devices::devices directly.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:21 +02:00
Anand Jain
c4babc5e38 btrfs: rename struct btrfs_fs_devices::list
btrfs_fs_devices::list is the list of BTRFS fsid in the kernel, a generic
name 'list' makes it's search very difficult, rename it to fs_list.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:21 +02:00
Nikolay Borisov
be97f133b3 btrfs: Drop fs_info parameter from btrfs_merge_delayed_refs
It's provided by the transaction handle.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:20 +02:00
Nikolay Borisov
f033798d12 btrfs: Drop fs_info parameter from add_delayed_data_ref
It's provided by the transaction handle.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:20 +02:00
Nikolay Borisov
1acda0c289 btrfs: Drop add_delayed_ref_head fs_info parameter
It's provided by the transaction handle.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:20 +02:00
Nikolay Borisov
40012f96b6 btrfs: Remove btrfs_wait_and_free_delalloc_work
This function is called from only 1 place and is effectively a wrapper
over wait_completion/kfree. It doesn't really bring any value having
those two calls in a separate function. Just open code it and remove it.
No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:20 +02:00
Nikolay Borisov
8ae225a8a4 btrfs: Remove tree argument from extent_writepages
It can be directly referenced from the passed address_space so do that.
No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:20 +02:00
Nikolay Borisov
81f1d39035 btrfs: Use list_empty instead of list_empty_careful
list_empty_careful usually is a signal of something tricky going on. Its
usage in btrfs is actually not needed since both lists it's used on are
local to a function and cannot be modified concurrently. So switch to
plain list_empty. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:19 +02:00
Nikolay Borisov
2a3ff0adc9 btrfs: Remove redundant tree argument from extent_readpages
This function is called only from btrfs_readpage and is already passed
the mapping. Simplify its signature by moving the code obtaining
reference to the extent tree in the function. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:19 +02:00
Nikolay Borisov
29c68b2de9 btrfs: Remove map argument from try_release_extent_state
It's not used in the function so just remove it. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:19 +02:00
Nikolay Borisov
477a30ba5f btrfs: Sink extent_tree arguments in try_release_extent_mapping
This function already gets the page from which the two extent trees
are referenced. Simplify its signature by moving the code getting the
trees inside the function. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:19 +02:00
Misono Tomohiro
a79a464d56 btrfs: Allow rmdir(2) to delete an empty subvolume
Change the behavior of rmdir(2) and allow it to delete an empty
subvolume by using btrfs_delete_subvolume() which is used by
btrfs_ioctl_snap_destroy().

This is a change in behaviour and has been requested by users. Deleting
the subvolume by ioctl requires root permissions while the rmdir way
does works with standard tools and syscalls for all users that can
access the subvolume.

The main usecase is to allow 'rm -rf /path/with/subvols' to simply work.
We were not able to find any nasty usability surprises, the intention is
to do the destructive rm. Without allowing rmdir, this would have to be
followed by the ioctl subvolume deletion, which is more of an annoyance.

Implementation details:

The required lock for @dir and inode of @dentry is already acquired in
vfs layer.

We need some check before deleting a subvolume. Permission check is done
in vfs layer, emptiness check is in btrfs_rmdir() and additional check
(i.e. neither the subvolume is a default subvolume nor send is in progress)
is in btrfs_delete_subvolume().

Note that in btrfs_ioctl_snap_destroy(), d_delete() is called after
btrfs_delete_subvolume(). For rmdir(2), d_delete() is called in vfs
layer later.

Tested-by: Goffredo Baroncelli <kreijack@inwind.it>
Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ enhance changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:18 +02:00
Misono Tomohiro
f60a2364a4 btrfs: Factor out the main deletion process from btrfs_ioctl_snap_destroy()
Factor out the second half of btrfs_ioctl_snap_destroy() as
btrfs_delete_subvolume(), which performs some subvolume specific checks
before deletion:

1. send is not in progress
2. the subvolume is not the default subvolume
3. the subvolume does not contain other subvolumes

and actual deletion process. btrfs_delete_subvolume() requires
inode_lock for both @dir and inode of @dentry. The remaining part of
btrfs_ioctl_snap_destroy() is mainly permission checks.

Note that call of d_delete() is not included in btrfs_delete_subvolume()
as this function will also be used by btrfs_rmdir() to delete an empty
subvolume and in that case d_delete() is called in VFS layer.

As a result, btrfs_unlink_subvol() and may_destroy_subvol()
become static functions. No functional changes.

Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor comment updates ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:18 +02:00
Misono Tomohiro
ec42f16734 btrfs: Move may_destroy_subvol() from ioctl.c to inode.c
This is a preparation work to refactor btrfs_ioctl_snap_destroy()
and to allow rmdir(2) to delete an empty subvolume.

Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor update of the function comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:18 +02:00
Howard McLauchlan
3b079a919a btrfs: remove unused le_test_bit()
With commit b18253ec57c0 ("btrfs: optimize free space tree bitmap
conversion"), there are no more callers to le_test_bit(). This patch
removes le_test_bit().

Signed-off-by: Howard McLauchlan <hmclauchlan@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:18 +02:00
Howard McLauchlan
a565971ff3 btrfs: optimize free space tree bitmap conversion
Presently, convert_free_space_to_extents() does a linear scan of the
bitmap. We can speed this up with find_next_{bit,zero_bit}_le().

This patch replaces the linear scan with find_next_{bit,zero_bit}_le().
Testing shows a 20-33% decrease in execution time for
convert_free_space_to_extents().

Since we change bitmap to be unsigned long, we have to do some casting
for the bitmap cursor. In le_bitmap_set() it makes sense to use u8, as
we are doing bit operations. Everywhere else, we're just using it for
pointer arithmetic and not directly accessing it, so char seems more
appropriate.

Suggested-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Howard McLauchlan <hmclauchlan@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:18 +02:00
Howard McLauchlan
6faa8f475e btrfs: clean up le_bitmap_{set, clear}()
le_bitmap_set() is only used by free-space-tree, so move it there and
make it static. le_bitmap_clear() is not used, so remove it.

Signed-off-by: Howard McLauchlan <hmclauchlan@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:18 +02:00
David Sterba
f46b24c945 btrfs: use fs_info for btrfs_handle_em_exist tracepoint
We really want to know to which filesystem the extent map events belong,
but as it cannot be reached from the extent_map pointers, we need to
pass it down the callchain.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:17 +02:00
David Sterba
0e08eb9b1c btrfs: tests: pass fs_info to extent_map tests
Preparatory work to pass fs_info to btrfs_add_extent_mapping so we can
get a better tracepoint message. Extent maps do not need fs_info for
anything so we only add a dummy one without any other initialization.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:17 +02:00
Nikolay Borisov
57f1642ec3 btrfs: Consolidate error checking for btrfs_alloc_chunk
The second if is really a subcase of ret being less than 0. So
introduce a generic if (ret < 0) check, and inside have another if
which explicitly handles the -ENOSPC and any other errors. No
functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:16 +02:00
Nikolay Borisov
1e7a14211b btrfs: Fix lock release order
Locks should generally be released in the oppposite order they are
acquired. Generally lock acquisiton ordering is used to ensure
deadlocks don't happen. However, as becomes more complicated it's
best to also maintain proper unlock order so as to avoid possible dead
locks. This was found by code inspection and doesn't necessarily lead
to a deadlock scenario.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:16 +02:00
Nikolay Borisov
b25f0d0012 btrfs: Use while loop instead of labels in __endio_write_update_ordered
Currently __endio_write_update_ordered uses labels to implement
what is essentially a simple while loop. This makes the code more
cumbersome to follow than it actually has to be. No functional
changes. No xfstest regressions were found during testing.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:15 +02:00
Anand Jain
89595e80de btrfs: add comment about BTRFS_FS_EXCL_OP
Adds comments about BTRFS_FS_EXCL_OP to existing comments
about the device locks.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor updates ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:15 +02:00
Nikolay Borisov
41d0bd3b5e btrfs: Drop delayed_refs argument from btrfs_check_delayed_seq
It's used to print its pointer in a debug statement but doesn't really
bring any useful information to the error message.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 13:12:11 +02:00
Su Yue
c065f5b1cf btrfs: rename btrfs_get_block_group_info and make it static
The function btrfs_get_block_group_info() was introduced by the
commit 5af3e8cce8 ("Btrfs: make filesystem read-only when submitting
 barrier fails") which used it in disk-io.c.

However, the function is only called in ioctl.c now.
Its parameter type btrfs_ioctl_space_info* is only for ioctl.

So, make it static and rename it to be original name
get_block_group_info.

No functional change.

Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 13:12:11 +02:00
Nikolay Borisov
29d2b84cf9 btrfs: Replace owner argument in add_pinned_bytes with a boolean
add_pinned_bytes really cares whether the bytes being pinned are either
data or metadata. To that effect it checks whether the 'owner' argument
is less than BTRFS_FIRST_FREE_OBJECTID (256). This works because
owner can really have 2 types of values:

 a) For metadata extents it holds the level at which the parent is in
    the btree. This amounts to owner having the values 0-7

 b) In case of modifying data extents, owner is the inode number
    to which those extents belongs.

Let's make this more explicit byt converting the owner parameter to a
boolean value and either pass it directly when we know the type of
extents we are working with (i.e. in btrfs_free_tree_block). In cases
when the parent function can be called on both metadata/data extents
perform the check in the caller. This hopefully makes the interface
of add_pinned_bytes more intuitive.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 13:12:11 +02:00
Linus Torvalds
d7b66b4ab0 for-4.17-rc6-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAlsG/ecACgkQxWXV+ddt
 WDvr3w/8D12pwR9sPcEwxD4pvoLv7LP1VRQy2u+ivSifdBD7MueKh3y0igUMyARR
 LERsK0zUsTQGkkC6c7ZYd4cT9PikPpXtO1P9iATFAKqR/YMDIV/haSqT8DwbI/qb
 7F+ZMeTy1LzL01YlYBrGVDxP8AWVO2Dml6JolYxzplILSLvdPH6G8xOSjei/p9sm
 RK5ERHJENEI0l/cThpiLoAEWjzciPtR39T5Hq45onHyCs3bjJCcx51/QE8sBsl8x
 +BKvCmL40UKd30YKudJZYDM6NgMgWENhfTtIZQIInv99sMNCxIgTEUdX8ExdyjRZ
 24rst/BuQz4d8r/8zqE/hdFsHRGWwnEiYmGWylanPY5KdQ41ULfXC06xuoNOLoW8
 KQwD8SWv+W5vEJW0UQz5cb3vUgv5RnUzPvcmMfSztLeo2K4zj6zCK5L6XJwIJNbM
 1AJR7R4TRkQdf5QEeziFl738Yv1AgsPQuKSiiFa9YwXMLU8dYXlx14ioUzBL8MLe
 1wZPJ03x/N7eKJ0g6OIAAVfUTFFejv4Z2B2IDoObuLLsPwTdK6tS+9tJ5mos7ngG
 Vf1ZVmhmeJdw1qwK8ROzAJHkK807KgGO7LWmA7tIVLwWuZX14F7xLQIg3Ux3MhIh
 NhoBTFy2AGmdE0hFYv/4FA5dnUOU4VTVYVw3QUV4DMc0XIodZrE=
 =iYyx
 -----END PGP SIGNATURE-----

Merge tag 'for-4.17-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fix from David Sterba:
 "A one-liner that prevents leaking an internal error value 1 out of the
  ftruncate syscall.

  This has been observed in practice. The steps to reproduce make a
  common pattern (open/write/fync/ftruncate) but also need the
  application to not check only for negative values and happens only for
  compressed inlined files.

  The conditions are narrow but as this could break userspace I think
  it's better to merge it now and not wait for the merge window"

* tag 'for-4.17-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  Btrfs: fix error handling in btrfs_truncate()
2018-05-24 11:47:43 -07:00
Omar Sandoval
d50147381a Btrfs: fix error handling in btrfs_truncate()
Jun Wu at Facebook reported that an internal service was seeing a return
value of 1 from ftruncate() on Btrfs in some cases. This is coming from
the NEED_TRUNCATE_BLOCK return value from btrfs_truncate_inode_items().

btrfs_truncate() uses two variables for error handling, ret and err.
When btrfs_truncate_inode_items() returns non-zero, we set err to the
return value. However, NEED_TRUNCATE_BLOCK is not an error. Make sure we
only set err if ret is an error (i.e., negative).

To reproduce the issue: mount a filesystem with -o compress-force=zstd
and the following program will encounter return value of 1 from
ftruncate:

int main(void) {
        char buf[256] = { 0 };
        int ret;
        int fd;

        fd = open("test", O_CREAT | O_WRONLY | O_TRUNC, 0666);
        if (fd == -1) {
                perror("open");
                return EXIT_FAILURE;
        }

        if (write(fd, buf, sizeof(buf)) != sizeof(buf)) {
                perror("write");
                close(fd);
                return EXIT_FAILURE;
        }

        if (fsync(fd) == -1) {
                perror("fsync");
                close(fd);
                return EXIT_FAILURE;
        }

        ret = ftruncate(fd, 128);
        if (ret) {
                printf("ftruncate() returned %d\n", ret);
                close(fd);
                return EXIT_FAILURE;
        }

        close(fd);
        return EXIT_SUCCESS;
}

Fixes: ddfae63cc8 ("btrfs: move btrfs_truncate_block out of trans handle")
CC: stable@vger.kernel.org # 4.15+
Reported-by: Jun Wu <quark@fb.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-24 11:56:57 +02:00
Linus Torvalds
5997aab0a1 Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro:
 "Assorted fixes all over the place"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  aio: fix io_destroy(2) vs. lookup_ioctx() race
  ext2: fix a block leak
  nfsd: vfs_mkdir() might succeed leaving dentry negative unhashed
  cachefiles: vfs_mkdir() might succeed leaving dentry negative unhashed
  unfuck sysfs_mount()
  kernfs: deal with kernfs_fill_super() failures
  cramfs: Fix IS_ENABLED typo
  befs_lookup(): use d_splice_alias()
  affs_lookup: switch to d_splice_alias()
  affs_lookup(): close a race with affs_remove_link()
  fix breakage caused by d_find_alias() semantics change
  fs: don't scan the inode cache before SB_BORN is set
  do d_instantiate/unlock_new_inode combinations safely
  iov_iter: fix memory leak in pipe_get_pages_alloc()
  iov_iter: fix return type of __pipe_get_pages()
2018-05-21 11:54:57 -07:00
Linus Torvalds
e5e03ad9e0 for-4.17-rc5-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAlsBhWUACgkQxWXV+ddt
 WDsl5g/7BwC4g1BICBG5SXKG9e/s0gjf/3xh7XI8g9kYYu3NktH4fWqDNNncgKtQ
 LL4WTcFhYJ+Cx/wkgPoYHfR9CKN2dR038S1OneKz+nhP/dTXw1MnSmfNP4kECqSQ
 vwdeDKwlO0Qsy2PdSLjLk8/Yn43wNleBI0swEF+5q7AQgv7XW9hk1oCpwJ7gjDw2
 Ymb3WVlj/V0QhnZRnQEgnRwK4xLiOBszb6C+fxQDjtismWDz12dY3udl6Co18YTW
 DnmH3x9qBXpL7D2S/6AtZcafbrfgSeL6PXTlcb1fLHK1HwZbdUAerUrVVlV2aitC
 rHbg+pD0X1uzDCt2iZ7MROnZv/gLbU9OSz1foE9pw8xU9J5zbsvLlBSK4P0mdEzI
 MaZzqB3H31cUSZJq/BUdGnFAOIykcOEvscn000p/cy7szv+GpWb08rTqvVgZvSM2
 ai1qADU7ACaWdFjJUqbOi3zWyT6AcGONwjfSIaa/y3DyGzVX3UyJxeIuvznPS2Yt
 17B4GRIbF1xPbNRRBw7N60E8o4p8t+BMftStMCBSl8zxnjd6RPOCluOH/az6tL+H
 hmY/nGvJZCj3Y6SeLGiKXdNH9MFkhcvEIvePFkUt3AEEHcCtdG5RebrAvVSpO+N4
 1SUAE1y8Cbco/KYMjlERpIzZIKOBkD/EnSBIXTI9mIVC0op6mII=
 =bhlK
 -----END PGP SIGNATURE-----

Merge tag 'for-4.17-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "We've accumulated some fixes during the last week, some of them were
  in the works for a longer time but there are some newer ones too.

  Most of the fixes have a reproducer and fix user visible problems,
  also candidates for stable kernels. They IMHO qualify for a late rc,
  though I did not expect that many"

* tag 'for-4.17-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: fix crash when trying to resume balance without the resume flag
  btrfs: Fix delalloc inodes invalidation during transaction abort
  btrfs: Split btrfs_del_delalloc_inode into 2 functions
  btrfs: fix reading stale metadata blocks after degraded raid1 mounts
  btrfs: property: Set incompat flag if lzo/zstd compression is set
  Btrfs: fix duplicate extents after fsync of file with prealloc extents
  Btrfs: fix xattr loss after power failure
  Btrfs: send, fix invalid access to commit roots due to concurrent snapshotting
2018-05-20 12:04:27 -07:00
Anand Jain
02ee654d3a btrfs: fix crash when trying to resume balance without the resume flag
We set the BTRFS_BALANCE_RESUME flag in the btrfs_recover_balance()
only, which isn't called during the remount. So when resuming from
the paused balance we hit the bug:

 kernel: kernel BUG at fs/btrfs/volumes.c:3890!
 ::
 kernel:  balance_kthread+0x51/0x60 [btrfs]
 kernel:  kthread+0x111/0x130
 ::
 kernel: RIP: btrfs_balance+0x12e1/0x1570 [btrfs] RSP: ffffba7d0090bde8

Reproducer:
  On a mounted filesystem:

  btrfs balance start --full-balance /btrfs
  btrfs balance pause /btrfs
  mount -o remount,ro /dev/sdb /btrfs
  mount -o remount,rw /dev/sdb /btrfs

To fix this set the BTRFS_BALANCE_RESUME flag in
btrfs_resume_balance_async().

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-17 14:38:24 +02:00
Nikolay Borisov
fe816d0f1d btrfs: Fix delalloc inodes invalidation during transaction abort
When a transaction is aborted btrfs_cleanup_transaction is called to
cleanup all the various in-flight bits and pieces which migth be
active. One of those is delalloc inodes - inodes which have dirty
pages which haven't been persisted yet. Currently the process of
freeing such delalloc inodes in exceptional circumstances such as
transaction abort boiled down to calling btrfs_invalidate_inodes whose
sole job is to invalidate the dentries for all inodes related to a
root. This is in fact wrong and insufficient since such delalloc inodes
will likely have pending pages or ordered-extents and will be linked to
the sb->s_inode_list. This means that unmounting a btrfs instance with
an aborted transaction could potentially lead inodes/their pages
visible to the system long after their superblock has been freed. This
in turn leads to a "use-after-free" situation once page shrink is
triggered. This situation could be simulated by running generic/019
which would cause such inodes to be left hanging, followed by
generic/176 which causes memory pressure and page eviction which lead
to touching the freed super block instance. This situation is
additionally detected by the unmount code of VFS with the following
message:

"VFS: Busy inodes after unmount of Self-destruct in 5 seconds.  Have a nice day..."

Additionally btrfs hits WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
in free_fs_root for the same reason.

This patch aims to rectify the sitaution by doing the following:

1. Change btrfs_destroy_delalloc_inodes so that it calls
invalidate_inode_pages2 for every inode on the delalloc list, this
ensures that all the pages of the inode are released. This function
boils down to calling btrfs_releasepage. During test I observed cases
where inodes on the delalloc list were having an i_count of 0, so this
necessitates using igrab to be sure we are working on a non-freed inode.

2. Since calling btrfs_releasepage might queue delayed iputs move the
call out to btrfs_cleanup_transaction in btrfs_error_commit_super before
calling run_delayed_iputs for the last time. This is necessary to ensure
that delayed iputs are run.

Note: this patch is tagged for 4.14 stable but the fix applies to older
versions too but needs to be backported manually due to conflicts.

CC: stable@vger.kernel.org # 4.14.x: 2b87733134: btrfs: Split btrfs_del_delalloc_inode into 2 functions
CC: stable@vger.kernel.org # 4.14.x
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add comment to igrab ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-17 14:38:18 +02:00
Nikolay Borisov
2b87733134 btrfs: Split btrfs_del_delalloc_inode into 2 functions
This is in preparation of fixing delalloc inodes leakage on transaction
abort. Also export the new function.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-17 14:18:26 +02:00
Liu Bo
02a3307aa9 btrfs: fix reading stale metadata blocks after degraded raid1 mounts
If a btree block, aka. extent buffer, is not available in the extent
buffer cache, it'll be read out from the disk instead, i.e.

btrfs_search_slot()
  read_block_for_search()  # hold parent and its lock, go to read child
    btrfs_release_path()
    read_tree_block()  # read child

Unfortunately, the parent lock got released before reading child, so
commit 5bdd3536cb ("Btrfs: Fix block generation verification race") had
used 0 as parent transid to read the child block.  It forces
read_tree_block() not to check if parent transid is different with the
generation id of the child that it reads out from disk.

A simple PoC is included in btrfs/124,

0. A two-disk raid1 btrfs,

1. Right after mkfs.btrfs, block A is allocated to be device tree's root.

2. Mount this filesystem and put it in use, after a while, device tree's
   root got COW but block A hasn't been allocated/overwritten yet.

3. Umount it and reload the btrfs module to remove both disks from the
   global @fs_devices list.

4. mount -odegraded dev1 and write some data, so now block A is allocated
   to be a leaf in checksum tree.  Note that only dev1 has the latest
   metadata of this filesystem.

5. Umount it and mount it again normally (with both disks), since raid1
   can pick up one disk by the writer task's pid, if btrfs_search_slot()
   needs to read block A, dev2 which does NOT have the latest metadata
   might be read for block A, then we got a stale block A.

6. As parent transid is not checked, block A is marked as uptodate and
   put into the extent buffer cache, so the future search won't bother
   to read disk again, which means it'll make changes on this stale
   one and make it dirty and flush it onto disk.

To avoid the problem, parent transid needs to be passed to
read_tree_block().

In order to get a valid parent transid, we need to hold the parent's
lock until finishing reading child.

This patch needs to be slightly adapted for stable kernels, the
&first_key parameter added to read_tree_block() is from 4.16+
(581c176041). The fix is to replace 0 by 'gen'.

Fixes: 5bdd3536cb ("Btrfs: Fix block generation verification race")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-17 14:18:25 +02:00
Misono Tomohiro
1a63c198dd btrfs: property: Set incompat flag if lzo/zstd compression is set
Incompat flag of LZO/ZSTD compression should be set at:

 1. mount time (-o compress/compress-force)
 2. when defrag is done
 3. when property is set

Currently 3. is missing and this commit adds this.

This could lead to a filesystem that uses ZSTD but is not marked as
such. If a kernel without a ZSTD support encounteres a ZSTD compressed
extent, it will handle that but this could be confusing to the user.

Typically the filesystem is mounted with the ZSTD option, but the
discrepancy can arise when a filesystem is never mounted with ZSTD and
then the property on some file is set (and some new extents are
written). A simple mount with -o compress=zstd will fix that up on an
unpatched kernel.

Same goes for LZO, but this has been around for a very long time
(2.6.37) so it's unlikely that a pre-LZO kernel would be used.

Fixes: 5c1aab1dd5 ("btrfs: Add zstd support")
CC: stable@vger.kernel.org # 4.14+
Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add user visible impact ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-17 14:18:25 +02:00
Filipe Manana
31d11b83b9 Btrfs: fix duplicate extents after fsync of file with prealloc extents
In commit 471d557afe ("Btrfs: fix loss of prealloc extents past i_size
after fsync log replay"), on fsync,  we started to always log all prealloc
extents beyond an inode's i_size in order to avoid losing them after a
power failure. However under some cases this can lead to the log replay
code to create duplicate extent items, with different lengths, in the
extent tree. That happens because, as of that commit, we can now log
extent items based on extent maps that are not on the "modified" list
of extent maps of the inode's extent map tree. Logging extent items based
on extent maps is used during the fast fsync path to save time and for
this to work reliably it requires that the extent maps are not merged
with other adjacent extent maps - having the extent maps in the list
of modified extents gives such guarantee.

Consider the following example, captured during a long run of fsstress,
which illustrates this problem.

We have inode 271, in the filesystem tree (root 5), for which all of the
following operations and discussion apply to.

A buffered write starts at offset 312391 with a length of 933471 bytes
(end offset at 1245862). At this point we have, for this inode, the
following extent maps with the their field values:

em A, start 0, orig_start 0, len 40960, block_start 18446744073709551613,
      block_len 0, orig_block_len 0
em B, start 40960, orig_start 40960, len 376832, block_start 1106399232,
      block_len 376832, orig_block_len 376832
em C, start 417792, orig_start 417792, len 782336, block_start
      18446744073709551613, block_len 0, orig_block_len 0
em D, start 1200128, orig_start 1200128, len 835584, block_start
      1106776064, block_len 835584, orig_block_len 835584
em E, start 2035712, orig_start 2035712, len 245760, block_start
      1107611648, block_len 245760, orig_block_len 245760

Extent map A corresponds to a hole and extent maps D and E correspond to
preallocated extents.

Extent map D ends where extent map E begins (1106776064 + 835584 =
1107611648), but these extent maps were not merged because they are in
the inode's list of modified extent maps.

An fsync against this inode is made, which triggers the fast path
(BTRFS_INODE_NEEDS_FULL_SYNC is not set). This fsync triggers writeback
of the data previously written using buffered IO, and when the respective
ordered extent finishes, btrfs_drop_extents() is called against the
(aligned) range 311296..1249279. This causes a split of extent map D at
btrfs_drop_extent_cache(), replacing extent map D with a new extent map
D', also added to the list of modified extents,  with the following
values:

em D', start 1249280, orig_start of 1200128,
       block_start 1106825216 (= 1106776064 + 1249280 - 1200128),
       orig_block_len 835584,
       block_len 786432 (835584 - (1249280 - 1200128))

Then, during the fast fsync, btrfs_log_changed_extents() is called and
extent maps D' and E are removed from the list of modified extents. The
flag EXTENT_FLAG_LOGGING is also set on them. After the extents are logged
clear_em_logging() is called on each of them, and that makes extent map E
to be merged with extent map D' (try_merge_map()), resulting in D' being
deleted and E adjusted to:

em E, start 1249280, orig_start 1200128, len 1032192,
      block_start 1106825216, block_len 1032192,
      orig_block_len 245760

A direct IO write at offset 1847296 and length of 360448 bytes (end offset
at 2207744) starts, and at that moment the following extent maps exist for
our inode:

em A, start 0, orig_start 0, len 40960, block_start 18446744073709551613,
      block_len 0, orig_block_len 0
em B, start 40960, orig_start 40960, len 270336, block_start 1106399232,
      block_len 270336, orig_block_len 376832
em C, start 311296, orig_start 311296, len 937984, block_start 1112842240,
      block_len 937984, orig_block_len 937984
em E (prealloc), start 1249280, orig_start 1200128, len 1032192,
      block_start 1106825216, block_len 1032192, orig_block_len 245760

The dio write results in drop_extent_cache() being called twice. The first
time for a range that starts at offset 1847296 and ends at offset 2035711
(length of 188416), which results in a double split of extent map E,
replacing it with two new extent maps:

em F, start 1249280, orig_start 1200128, block_start 1106825216,
      block_len 598016, orig_block_len 598016
em G, start 2035712, orig_start 1200128, block_start 1107611648,
      block_len 245760, orig_block_len 1032192

It also creates a new extent map that represents a part of the requested
IO (through create_io_em()):

em H, start 1847296, len 188416, block_start 1107423232, block_len 188416

The second call to drop_extent_cache() has a range with a start offset of
2035712 and end offset of 2207743 (length of 172032). This leads to
replacing extent map G with a new extent map I with the following values:

em I, start 2207744, orig_start 1200128, block_start 1107783680,
      block_len 73728, orig_block_len 1032192

It also creates a new extent map that represents the second part of the
requested IO (through create_io_em()):

em J, start 2035712, len 172032, block_start 1107611648, block_len 172032

The dio write set the inode's i_size to 2207744 bytes.

After the dio write the inode has the following extent maps:

em A, start 0, orig_start 0, len 40960, block_start 18446744073709551613,
      block_len 0, orig_block_len 0
em B, start 40960, orig_start 40960, len 270336, block_start 1106399232,
      block_len 270336, orig_block_len 376832
em C, start 311296, orig_start 311296, len 937984, block_start 1112842240,
      block_len 937984, orig_block_len 937984
em F, start 1249280, orig_start 1200128, len 598016,
      block_start 1106825216, block_len 598016, orig_block_len 598016
em H, start 1847296, orig_start 1200128, len 188416,
      block_start 1107423232, block_len 188416, orig_block_len 835584
em J, start 2035712, orig_start 2035712, len 172032,
      block_start 1107611648, block_len 172032, orig_block_len 245760
em I, start 2207744, orig_start 1200128, len 73728,
      block_start 1107783680, block_len 73728, orig_block_len 1032192

Now do some change to the file, like adding a xattr for example and then
fsync it again. This triggers a fast fsync path, and as of commit
471d557afe ("Btrfs: fix loss of prealloc extents past i_size after fsync
log replay"), we use the extent map I to log a file extent item because
it's a prealloc extent and it starts at an offset matching the inode's
i_size. However when we log it, we create a file extent item with a value
for the disk byte location that is wrong, as can be seen from the
following output of "btrfs inspect-internal dump-tree":

 item 1 key (271 EXTENT_DATA 2207744) itemoff 3782 itemsize 53
     generation 22 type 2 (prealloc)
     prealloc data disk byte 1106776064 nr 1032192
     prealloc data offset 1007616 nr 73728

Here the disk byte value corresponds to calculation based on some fields
from the extent map I:

  1106776064 = block_start (1107783680) - 1007616 (extent_offset)
  extent_offset = 2207744 (start) - 1200128 (orig_start) = 1007616

The disk byte value of 1106776064 clashes with disk byte values of the
file extent items at offsets 1249280 and 1847296 in the fs tree:

        item 6 key (271 EXTENT_DATA 1249280) itemoff 3568 itemsize 53
                generation 20 type 2 (prealloc)
                prealloc data disk byte 1106776064 nr 835584
                prealloc data offset 49152 nr 598016
        item 7 key (271 EXTENT_DATA 1847296) itemoff 3515 itemsize 53
                generation 20 type 1 (regular)
                extent data disk byte 1106776064 nr 835584
                extent data offset 647168 nr 188416 ram 835584
                extent compression 0 (none)
        item 8 key (271 EXTENT_DATA 2035712) itemoff 3462 itemsize 53
                generation 20 type 1 (regular)
                extent data disk byte 1107611648 nr 245760
                extent data offset 0 nr 172032 ram 245760
                extent compression 0 (none)
        item 9 key (271 EXTENT_DATA 2207744) itemoff 3409 itemsize 53
                generation 20 type 2 (prealloc)
                prealloc data disk byte 1107611648 nr 245760
                prealloc data offset 172032 nr 73728

Instead of the disk byte value of 1106776064, the value of 1107611648
should have been logged. Also the data offset value should have been
172032 and not 1007616.
After a log replay we end up getting two extent items in the extent tree
with different lengths, one of 835584, which is correct and existed
before the log replay, and another one of 1032192 which is wrong and is
based on the logged file extent item:

 item 12 key (1106776064 EXTENT_ITEM 835584) itemoff 3406 itemsize 53
    refs 2 gen 15 flags DATA
    extent data backref root 5 objectid 271 offset 1200128 count 2
 item 13 key (1106776064 EXTENT_ITEM 1032192) itemoff 3353 itemsize 53
    refs 1 gen 22 flags DATA
    extent data backref root 5 objectid 271 offset 1200128 count 1

Obviously this leads to many problems and a filesystem check reports many
errors:

 (...)
 checking extents
 Extent back ref already exists for 1106776064 parent 0 root 5 owner 271 offset 1200128 num_refs 1
 extent item 1106776064 has multiple extent items
 ref mismatch on [1106776064 835584] extent item 2, found 3
 Incorrect local backref count on 1106776064 root 5 owner 271 offset 1200128 found 2 wanted 1 back 0x55b1d0ad7680
 Backref 1106776064 root 5 owner 271 offset 1200128 num_refs 0 not found in extent tree
 Incorrect local backref count on 1106776064 root 5 owner 271 offset 1200128 found 1 wanted 0 back 0x55b1d0ad4e70
 Backref bytes do not match extent backref, bytenr=1106776064, ref bytes=835584, backref bytes=1032192
 backpointer mismatch on [1106776064 835584]
 checking free space cache
 block group 1103101952 has wrong amount of free space
 failed to load free space cache for block group 1103101952
 checking fs roots
 (...)

So fix this by logging the prealloc extents beyond the inode's i_size
based on searches in the subvolume tree instead of the extent maps.

Fixes: 471d557afe ("Btrfs: fix loss of prealloc extents past i_size after fsync log replay")
CC: stable@vger.kernel.org # 4.14+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-17 14:18:19 +02:00
Filipe Manana
9a8fca62aa Btrfs: fix xattr loss after power failure
If a file has xattrs, we fsync it, to ensure we clear the flags
BTRFS_INODE_NEEDS_FULL_SYNC and BTRFS_INODE_COPY_EVERYTHING from its
inode, the current transaction commits and then we fsync it (without
either of those bits being set in its inode), we end up not logging
all its xattrs. This results in deleting all xattrs when replying the
log after a power failure.

Trivial reproducer

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt

  $ touch /mnt/foobar
  $ setfattr -n user.xa -v qwerty /mnt/foobar
  $ xfs_io -c "fsync" /mnt/foobar

  $ sync

  $ xfs_io -c "pwrite -S 0xab 0 64K" /mnt/foobar
  $ xfs_io -c "fsync" /mnt/foobar
  <power failure>

  $ mount /dev/sdb /mnt
  $ getfattr --absolute-names --dump /mnt/foobar
  <empty output>
  $

So fix this by making sure all xattrs are logged if we log a file's inode
item and neither the flags BTRFS_INODE_NEEDS_FULL_SYNC nor
BTRFS_INODE_COPY_EVERYTHING were set in the inode.

Fixes: 36283bf777 ("Btrfs: fix fsync xattr loss in the fast fsync path")
Cc: <stable@vger.kernel.org> # 4.2+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-14 16:42:43 +02:00
Robbie Ko
6f2f0b394b Btrfs: send, fix invalid access to commit roots due to concurrent snapshotting
[BUG]
btrfs incremental send BUG happens when creating a snapshot of snapshot
that is being used by send.

[REASON]
The problem can happen if while we are doing a send one of the snapshots
used (parent or send) is snapshotted, because snapshoting implies COWing
the root of the source subvolume/snapshot.

1. When doing an incremental send, the send process will get the commit
   roots from the parent and send snapshots, and add references to them
   through extent_buffer_get().

2. When a snapshot/subvolume is snapshotted, its root node is COWed
   (transaction.c:create_pending_snapshot()).

3. COWing releases the space used by the node immediately, through:

   __btrfs_cow_block()
   --btrfs_free_tree_block()
   ----btrfs_add_free_space(bytenr of node)

4. Because send doesn't hold a transaction open, it's possible that
   the transaction used to create the snapshot commits, switches the
   commit root and the old space used by the previous root node gets
   assigned to some other node allocation. Allocation of a new node will
   use the existing extent buffer found in memory, which we previously
   got a reference through extent_buffer_get(), and allow the extent
   buffer's content (pages) to be modified:

   btrfs_alloc_tree_block
   --btrfs_reserve_extent
   ----find_free_extent (get bytenr of old node)
   --btrfs_init_new_buffer (use bytenr of old node)
   ----btrfs_find_create_tree_block
   ------alloc_extent_buffer
   --------find_extent_buffer (get old node)

5. So send can access invalid memory content and have unpredictable
   behaviour.

[FIX]
So we fix the problem by copying the commit roots of the send and
parent snapshots and use those copies.

CallTrace looks like this:
 ------------[ cut here ]------------
 kernel BUG at fs/btrfs/ctree.c:1861!
 invalid opcode: 0000 [#1] SMP
 CPU: 6 PID: 24235 Comm: btrfs Tainted: P           O 3.10.105 #23721
 ffff88046652d680 ti: ffff88041b720000 task.ti: ffff88041b720000
 RIP: 0010:[<ffffffffa08dd0e8>] read_node_slot+0x108/0x110 [btrfs]
 RSP: 0018:ffff88041b723b68  EFLAGS: 00010246
 RAX: ffff88043ca6b000 RBX: ffff88041b723c50 RCX: ffff880000000000
 RDX: 000000000000004c RSI: ffff880314b133f8 RDI: ffff880458b24000
 RBP: 0000000000000000 R08: 0000000000000001 R09: ffff88041b723c66
 R10: 0000000000000001 R11: 0000000000001000 R12: ffff8803f3e48890
 R13: ffff8803f3e48880 R14: ffff880466351800 R15: 0000000000000001
 FS:  00007f8c321dc8c0(0000) GS:ffff88047fcc0000(0000)
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 R2: 00007efd1006d000 CR3: 0000000213a24000 CR4: 00000000003407e0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 Stack:
 ffff88041b723c50 ffff8803f3e48880 ffff8803f3e48890 ffff8803f3e48880
 ffff880466351800 0000000000000001 ffffffffa08dd9d7 ffff88041b723c50
 ffff8803f3e48880 ffff88041b723c66 ffffffffa08dde85 a9ff88042d2c4400
 Call Trace:
 [<ffffffffa08dd9d7>] ? tree_move_down.isra.33+0x27/0x50 [btrfs]
 [<ffffffffa08dde85>] ? tree_advance+0xb5/0xc0 [btrfs]
 [<ffffffffa08e83d4>] ? btrfs_compare_trees+0x2d4/0x760 [btrfs]
 [<ffffffffa0982050>] ? finish_inode_if_needed+0x870/0x870 [btrfs]
 [<ffffffffa09841ea>] ? btrfs_ioctl_send+0xeda/0x1050 [btrfs]
 [<ffffffffa094bd3d>] ? btrfs_ioctl+0x1e3d/0x33f0 [btrfs]
 [<ffffffff81111133>] ? handle_pte_fault+0x373/0x990
 [<ffffffff8153a096>] ? atomic_notifier_call_chain+0x16/0x20
 [<ffffffff81063256>] ? set_task_cpu+0xb6/0x1d0
 [<ffffffff811122c3>] ? handle_mm_fault+0x143/0x2a0
 [<ffffffff81539cc0>] ? __do_page_fault+0x1d0/0x500
 [<ffffffff81062f07>] ? check_preempt_curr+0x57/0x90
 [<ffffffff8115075a>] ? do_vfs_ioctl+0x4aa/0x990
 [<ffffffff81034f83>] ? do_fork+0x113/0x3b0
 [<ffffffff812dd7d7>] ? trace_hardirqs_off_thunk+0x3a/0x6c
 [<ffffffff81150cc8>] ? SyS_ioctl+0x88/0xa0
 [<ffffffff8153e422>] ? system_call_fastpath+0x16/0x1b
 ---[ end trace 29576629ee80b2e1 ]---

Fixes: 7069830a9e ("Btrfs: add btrfs_compare_trees function")
CC: stable@vger.kernel.org # 3.6+
Signed-off-by: Robbie Ko <robbieko@synology.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-14 16:42:34 +02:00
Al Viro
1e2e547a93 do d_instantiate/unlock_new_inode combinations safely
For anything NFS-exported we do _not_ want to unlock new inode
before it has grown an alias; original set of fixes got the
ordering right, but missed the nasty complication in case of
lockdep being enabled - unlock_new_inode() does
	lockdep_annotate_inode_mutex_key(inode)
which can only be done before anyone gets a chance to touch
->i_mutex.  Unfortunately, flipping the order and doing
unlock_new_inode() before d_instantiate() opens a window when
mkdir can race with open-by-fhandle on a guessed fhandle, leading
to multiple aliases for a directory inode and all the breakage
that follows from that.

	Correct solution: a new primitive (d_instantiate_new())
combining these two in the right order - lockdep annotate, then
d_instantiate(), then the rest of unlock_new_inode().  All
combinations of d_instantiate() with unlock_new_inode() should
be converted to that.

Cc: stable@kernel.org	# 2.6.29 and later
Tested-by: Mike Marshall <hubcap@omnibond.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-11 15:36:37 -04:00
Linus Torvalds
4148d3884a for-4.17-rc3-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAlrsbkEACgkQxWXV+ddt
 WDvm6Q/+KdFKJ7T8hBOc6o5EeULXCDF3FmMA7HvDC696WXKsckXJFKk52awvrSb6
 3wnIzfWmI3K+rwX3cKqLRKe6tMXtBrTjVWXyezfvx1SMcCO4hSQ+nWLqK08htaNf
 h7m3OC3y0xO8QHcFSkvHUov6KRWG3rH+4p46JsJjN7GTBtWmR6tsiyQQ9JMC3gNR
 8Jnl1YaQq/JDLFm8GmFfPqIK+MLnNJ+GOJC1pm2vJQFtjnDw9dic+dI2hGX2oh9M
 SSRAoJu7jUvTWSmQN9aJfbBUr4atzoKKGYsyAgx5qgXbzOnbUGTIhtyAZirRWWBy
 0pT2b/8XuqsIabwR5dR4UbL4Ke1h5DS4c6GFydwO4DeddTovHtDzbN0cPuPQABL1
 rwFzlnHhcM/qRu9SKXx1jRy7w4Vju8fVX9D4lyjLcyk24flkEAn1NlJCWEqSzPYR
 ikTTm71r/1/62XqE6AcOyugS8E6EYtYHo3PjrfFXr3fQCbctTLEaUKoegFkTezbX
 EZLRPy9KNGfuyUyh3eiSypNHZZ9WiT+W42BaLIcpbHJLnqB+A14Z0oZx6aHVhY0T
 VFLL91O//OmUvjpsZ7I99LyswvrzsmU0jKS41GXOQlLsLTxtGhcZbvRt4uX4UUie
 UOQrNCgO0Y2slGfv+uoDCLhH0tTCRziuEvmgu8bjPcfZE7tph+s=
 =Jdmp
 -----END PGP SIGNATURE-----

Merge tag 'for-4.17-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "Two regression fixes and one fix for stable"

* tag 'for-4.17-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  Btrfs: send, fix missing truncate for inode with prealloc extent past eof
  btrfs: Take trans lock before access running trans in check_delayed_ref
  btrfs: Fix wrong first_key parameter in replace_path
2018-05-04 20:32:18 -10:00
Filipe Manana
a6aa10c70b Btrfs: send, fix missing truncate for inode with prealloc extent past eof
An incremental send operation can miss a truncate operation when an inode
has an increased size in the send snapshot and a prealloc extent beyond
its size.

Consider the following scenario where a necessary truncate operation is
missing in the incremental send stream:

1) In the parent snapshot an inode has a size of 1282957 bytes and it has
   no prealloc extents beyond its size;

2) In the the send snapshot it has a size of 5738496 bytes and has a new
   extent at offsets 1884160 (length of 106496 bytes) and a prealloc
   extent beyond eof at offset 6729728 (and a length of 339968 bytes);

3) When processing the prealloc extent, at offset 6729728, we end up at
   send.c:send_write_or_clone() and set the @len variable to a value of
   18446744073708560384 because @offset plus the original @len value is
   larger then the inode's size (6729728 + 339968 > 5738496). We then
   call send_extent_data(), with that @offset and @len, which in turn
   calls send_write(), and then the later calls fill_read_buf(). Because
   the offset passed to fill_read_buf() is greater then inode's i_size,
   this function returns 0 immediately, which makes send_write() and
   send_extent_data() do nothing and return immediately as well. When
   we get back to send.c:send_write_or_clone() we adjust the value
   of sctx->cur_inode_next_write_offset to @offset plus @len, which
   corresponds to 6729728 + 18446744073708560384 = 5738496, which is
   precisely the the size of the inode in the send snapshot;

4) Later when at send.c:finish_inode_if_needed() we determine that
   we don't need to issue a truncate operation because the value of
   sctx->cur_inode_next_write_offset corresponds to the inode's new
   size, 5738496 bytes. This is wrong because the last write operation
   that was issued started at offset 1884160 with a length of 106496
   bytes, so the correct value for sctx->cur_inode_next_write_offset
   should be 1990656 (1884160 + 106496), so that a truncate operation
   with a value of 5738496 bytes would have been sent to insert a
   trailing hole at the destination.

So fix the issue by making send.c:send_write_or_clone() not attempt
to send write or clone operations for extents that start beyond the
inode's size, since such attempts do nothing but waste time by
calling helper functions and allocating path structures, and send
currently has no fallocate command in order to create prealloc extents
at the destination (either beyond a file's eof or not).

The issue was found running the test btrfs/007 from fstests using a seed
value of 1524346151 for fsstress.

Reported-by: Gu, Jinxiang <gujx@cn.fujitsu.com>
Fixes: ffa7c4296e ("Btrfs: send, do not issue unnecessary truncate operations")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-02 11:55:29 +02:00
ethanwu
998ac6d21c btrfs: Take trans lock before access running trans in check_delayed_ref
In preivous patch:
Btrfs: kill trans in run_delalloc_nocow and btrfs_cross_ref_exist
We avoid starting btrfs transaction and get this information from
fs_info->running_transaction directly.

When accessing running_transaction in check_delayed_ref, there's a
chance that current transaction will be freed by commit transaction
after the NULL pointer check of running_transaction is passed.

After looking all the other places using fs_info->running_transaction,
they are either protected by trans_lock or holding the transactions.

Fix this by using trans_lock and increasing the use_count.

Fixes: e4c3b2dcd1 ("Btrfs: kill trans in run_delalloc_nocow and btrfs_cross_ref_exist")
CC: stable@vger.kernel.org # 4.14+
Signed-off-by: ethanwu <ethanwu@synology.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-02 11:54:58 +02:00
Qu Wenruo
17515f1b76 btrfs: Fix wrong first_key parameter in replace_path
Commit 581c176041 ("btrfs: Validate child tree block's level and first
key") introduced new @first_key parameter for read_tree_block(), however
caller in replace_path() is parasing wrong key to read_tree_block().

It should use parameter @first_key other than @key.

Normally it won't expose problem as @key is normally initialzied to the
same value of @first_key we expect.
However in relocation recovery case, @key can be set to (0, 0, 0), and
since no valid key in relocation tree can be (0, 0, 0), it will cause
read_tree_block() to return -EUCLEAN and interrupt relocation recovery.

Fix it by setting @first_key correctly.

Fixes: 581c176041 ("btrfs: Validate child tree block's level and first key")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-26 13:21:04 +02:00
Linus Torvalds
d54b5c1315 for-4.17-rc1-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAlrcop8ACgkQxWXV+ddt
 WDuT2Q/9HZo9b1N4f+dM38P/cyBwEt9VYT0MLzpIpOid6ogpdF+1E7F6rDnUOyEQ
 0Me+znhC7kgXLBnpUDS16/2uGbp9VgCZo9NSq8juLrowGYpe9asadWbCqfFBmAh6
 Pc6r03Z1Z1EhXXUSm0cqJwvNHpNN6WnfBP1ithcp4OAltjVZ7IU45xHCcymfTxi+
 R6/kvJlG56YXoT97on/CHF85pAidELJ7CysLBGpCHP7Yl/lkVkyPVxSZO9up6ZtS
 078l0nCG9PpzONbdUcB9QGICPDcNLbBDhrS8yzQ+oajiRBz0+Im4c2UUvmZEUiMb
 6EAo6QV58OFUskgsY1cHWgZGS3YIFwzpmdsRQrCyuI4Z+1KXVu+RWMv1hF1G1Dqw
 8fHDm6+V2oqcoK3lSnb40UUySGw2d7PwjGxUk5iGKWISdmrxQsLcgkY/ERbjZxar
 emelwAZbsPwUNYNJj8qbm1QZlmys8FACKzJqyCR6+7/n353uWE30Tnv1MgfJg0nQ
 7ejk3U96R+oynN/9WOBFCLpuvPCbYaZk4eA9+3EjcSLzN81r/WtbgQDntEWi9auO
 /OUADaHOXoIaUnTBNtFV9DTseDW21hQ/4NseTVVsjKGWjh2qWRoEwuqI7TEZD/4M
 kGgdJL+xvD0MzR6Tq7xbhnQTcCOwH6NQ7aI4rI3abDbU9ZPuDrY=
 =lgaO
 -----END PGP SIGNATURE-----

Merge tag 'for-4.17-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "This contains a few fixups to the qgroup patches that were merged this
  dev cycle, unaligned access fix, blockgroup removal corner case fix
  and a small debugging output tweak"

* tag 'for-4.17-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: print-tree: debugging output enhancement
  btrfs: Fix race condition between delayed refs and blockgroup removal
  btrfs: fix unaligned access in readdir
  btrfs: Fix wrong btrfs_delalloc_release_extents parameter
  btrfs: delayed-inode: Remove wrong qgroup meta reservation calls
  btrfs: qgroup: Use independent and accurate per inode qgroup rsv
  btrfs: qgroup: Commit transaction in advance to reduce early EDQUOT
2018-04-22 12:09:27 -07:00
Qu Wenruo
c087232374 btrfs: print-tree: debugging output enhancement
This patch enhances the following things:

- tree block header
  * add generation and owner output for node and leaf
- node pointer generation output
- allow btrfs_print_tree() to not follow nodes
  * just like btrfs-progs

Please note that, although function btrfs_print_tree() is not called by
anyone right now, it's still a pretty useful function to debug kernel.
So that function is still kept for later use.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-20 19:18:16 +02:00
Nikolay Borisov
5e388e9581 btrfs: Fix race condition between delayed refs and blockgroup removal
When the delayed refs for a head are all run, eventually
cleanup_ref_head is called which (in case of deletion) obtains a
reference for the relevant btrfs_space_info struct by querying the bg
for the range. This is problematic because when the last extent of a
bg is deleted a race window emerges between removal of that bg and the
subsequent invocation of cleanup_ref_head. This can result in cache being null
and either a null pointer dereference or assertion failure.

	task: ffff8d04d31ed080 task.stack: ffff9e5dc10cc000
	RIP: 0010:assfail.constprop.78+0x18/0x1a [btrfs]
	RSP: 0018:ffff9e5dc10cfbe8 EFLAGS: 00010292
	RAX: 0000000000000044 RBX: 0000000000000000 RCX: 0000000000000000
	RDX: ffff8d04ffc1f868 RSI: ffff8d04ffc178c8 RDI: ffff8d04ffc178c8
	RBP: ffff8d04d29e5ea0 R08: 00000000000001f0 R09: 0000000000000001
	R10: ffff9e5dc0507d58 R11: 0000000000000001 R12: ffff8d04d29e5ea0
	R13: ffff8d04d29e5f08 R14: ffff8d04efe29b40 R15: ffff8d04efe203e0
	FS:  00007fbf58ead500(0000) GS:ffff8d04ffc00000(0000) knlGS:0000000000000000
	CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
	CR2: 00007fe6c6975648 CR3: 0000000013b2a000 CR4: 00000000000006f0
	DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
	DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
	Call Trace:
	 __btrfs_run_delayed_refs+0x10e7/0x12c0 [btrfs]
	 btrfs_run_delayed_refs+0x68/0x250 [btrfs]
	 btrfs_should_end_transaction+0x42/0x60 [btrfs]
	 btrfs_truncate_inode_items+0xaac/0xfc0 [btrfs]
	 btrfs_evict_inode+0x4c6/0x5c0 [btrfs]
	 evict+0xc6/0x190
	 do_unlinkat+0x19c/0x300
	 do_syscall_64+0x74/0x140
	 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
	RIP: 0033:0x7fbf589c57a7

To fix this, introduce a new flag "is_system" to head_ref structs,
which is populated at insertion time. This allows to decouple the
querying for the spaceinfo from querying the possibly deleted bg.

Fixes: d7eae3403f ("Btrfs: rework delayed ref total_bytes_pinned accounting")
CC: stable@vger.kernel.org # 4.14+
Suggested-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-20 19:17:25 +02:00
David Sterba
92d3217084 btrfs: fix unaligned access in readdir
The last update to readdir introduced a temporary buffer to store the
emitted readdir data, but as there are file names of variable length,
there's a lot of unaligned access.

This was observed on a sparc64 machine:

  Kernel unaligned access at TPC[102f3080] btrfs_real_readdir+0x51c/0x718 [btrfs]

Fixes: 23b5ec7494 ("btrfs: fix readdir deadlock with pagefault")
CC: stable@vger.kernel.org # 4.14+
Reported-and-tested-by: René Rebe <rene@exactcode.com>
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-19 00:35:08 +02:00
Qu Wenruo
336a8bb8e3 btrfs: Fix wrong btrfs_delalloc_release_extents parameter
Commit 43b18595d6 ("btrfs: qgroup: Use separate meta reservation type
for delalloc") merged into mainline is not the latest version submitted
to mail list in Dec 2017.

It has a fatal wrong @qgroup_free parameter, which results increasing
qgroup metadata pertrans reserved space, and causing a lot of early EDQUOT.

Fix it by applying the correct diff on top of current branch.

Fixes: 43b18595d6 ("btrfs: qgroup: Use separate meta reservation type for delalloc")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-18 16:46:57 +02:00
Qu Wenruo
f218ea6c47 btrfs: delayed-inode: Remove wrong qgroup meta reservation calls
Commit 4f5427ccce ("btrfs: delayed-inode: Use new qgroup meta rsv for
delayed inode and item") merged into mainline was not latest version
submitted to the mail list in Dec 2017.

Which lacks the following fixes:

1) Remove btrfs_qgroup_convert_reserved_meta() call in
   btrfs_delayed_item_release_metadata()
2) Remove btrfs_qgroup_reserve_meta_prealloc() call in
   btrfs_delayed_inode_reserve_metadata()

Those fixes will resolve unexpected EDQUOT problems.

Fixes: 4f5427ccce ("btrfs: delayed-inode: Use new qgroup meta rsv for delayed inode and item")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-18 16:46:55 +02:00
Qu Wenruo
ff6bc37eb7 btrfs: qgroup: Use independent and accurate per inode qgroup rsv
Unlike reservation calculation used in inode rsv for metadata, qgroup
doesn't really need to care about things like csum size or extent usage
for the whole tree COW.

Qgroups care more about net change of the extent usage.
That's to say, if we're going to insert one file extent, it will mostly
find its place in COWed tree block, leaving no change in extent usage.
Or causing a leaf split, resulting in one new net extent and increasing
qgroup number by nodesize.
Or in an even more rare case, increase the tree level, increasing qgroup
number by 2 * nodesize.

So here instead of using the complicated calculation for extent
allocator, which cares more about accuracy and no error, qgroup doesn't
need that over-estimated reservation.

This patch will maintain 2 new members in btrfs_block_rsv structure for
qgroup, using much smaller calculation for qgroup rsv, reducing false
EDQUOT.

Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
2018-04-18 16:46:51 +02:00
Qu Wenruo
a514d63882 btrfs: qgroup: Commit transaction in advance to reduce early EDQUOT
Unlike previous method that tries to commit transaction inside
qgroup_reserve(), this time we will try to commit transaction using
fs_info->transaction_kthread to avoid nested transaction and no need to
worry about locking context.

Since it's an asynchronous function call and we won't wait for
transaction commit, unlike previous method, we must call it before we
hit the qgroup limit.

So this patch will use the ratio and size of qgroup meta_pertrans
reservation as indicator to check if we should trigger a transaction
commit.  (meta_prealloc won't be cleaned in transaction committ, it's
useless anyway)

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-18 16:46:47 +02:00
Linus Torvalds
e37563bb6c for-4.17-part2-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAlrTQ4sACgkQxWXV+ddt
 WDti3Q/+MAeqsLTjvre2RQ3ka5hNyCuVftUIBmcP3YfJbt+xZYQyaewW4Xkfi3cm
 cbJE+zehzf5ag+RJhxk3OwFTvNfLGIO9asWs3b08NGUi6VzwL0/8B/iOdZPuHSAV
 TrecQIBE2Tp+xax9cQEnxav34D4dUtXNaDweGjp1MIIUkDneQP/I0vlTu7vafBgX
 UVxP6riL/MCs7sjTHGIPs0lv8L/fgdmo+dk5SnNuIPTOcFTQXgVrtHjw9IvbKWd4
 aq+sbNWoSrhXUfllbFg/wZqDe9tWn9E2f6m/H0ThSoNdxusSVgacOjFRYh20NKLW
 WGB8Amd/ItGtJwJ1CIypa7VX2U11UAi0XT7BeiK82rUNEJ6moRqFOXG861gRLoTZ
 SpH8uWO+e+CogfXob1KCndn5lot4AM2ZTkCqfrjpM35Nul72PZdne0CxNlmiRupY
 Fdt5GB+sg8plcMaRiYr++BbbHP5tggX1MrhLGEbx2XBs2eRdn+2Lv2I1Ig/U4NUb
 Vf+xk/tFLKGOTSZlbv7SV7ekXxG/3+7gAuL7A1XMETZCwBF4L3hwyW7CgkEBb3PC
 TqX8BwMaRpyp/FgW/QL6edjXZ3a64VaHIfqRPNks3lWWcCHVbzyiVPfEjx+AEJ/0
 abx6jXTJhLUBPuPxEgb5rsSv62RoxPoYHqCErrG95XwnZ8rSCts=
 =I0y0
 -----END PGP SIGNATURE-----

Merge tag 'for-4.17-part2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull more btrfs updates from David Sterba:
 "We have queued a few more fixes (error handling, log replay,
  softlockup) and the rest is SPDX updates that touche almost all files
  so the diffstat is long"

* tag 'for-4.17-part2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: Only check first key for committed tree blocks
  btrfs: add SPDX header to Kconfig
  btrfs: replace GPL boilerplate by SPDX -- sources
  btrfs: replace GPL boilerplate by SPDX -- headers
  Btrfs: fix loss of prealloc extents past i_size after fsync log replay
  Btrfs: clean up resources during umount after trans is aborted
  btrfs: Fix possible softlock on single core machines
  Btrfs: bail out on error during replay_dir_deletes
  Btrfs: fix NULL pointer dereference in log_dir_items
2018-04-15 18:08:35 -07:00
Qu Wenruo
5d41be6f70 btrfs: Only check first key for committed tree blocks
When looping btrfs/074 with many cpus (>= 8), it's possible to trigger
kernel warning due to first key verification:

[ 4239.523446] WARNING: CPU: 5 PID: 2381 at fs/btrfs/disk-io.c:460 btree_read_extent_buffer_pages+0x1ad/0x210
[ 4239.523830] Modules linked in:
[ 4239.524630] RIP: 0010:btree_read_extent_buffer_pages+0x1ad/0x210
[ 4239.527101] Call Trace:
[ 4239.527251]  read_tree_block+0x42/0x70
[ 4239.527434]  read_node_slot+0xd2/0x110
[ 4239.527632]  push_leaf_right+0xad/0x1b0
[ 4239.527809]  split_leaf+0x4ea/0x700
[ 4239.527988]  ? leaf_space_used+0xbc/0xe0
[ 4239.528192]  ? btrfs_set_lock_blocking_rw+0x99/0xb0
[ 4239.528416]  btrfs_search_slot+0x8cc/0xa40
[ 4239.528605]  btrfs_insert_empty_items+0x71/0xc0
[ 4239.528798]  __btrfs_run_delayed_refs+0xa98/0x1680
[ 4239.529013]  btrfs_run_delayed_refs+0x10b/0x1b0
[ 4239.529205]  btrfs_commit_transaction+0x33/0xaf0
[ 4239.529445]  ? start_transaction+0xa8/0x4f0
[ 4239.529630]  btrfs_alloc_data_chunk_ondemand+0x1b0/0x4e0
[ 4239.529833]  btrfs_check_data_free_space+0x54/0xa0
[ 4239.530045]  btrfs_delalloc_reserve_space+0x25/0x70
[ 4239.531907]  btrfs_direct_IO+0x233/0x3d0
[ 4239.532098]  generic_file_direct_write+0xcb/0x170
[ 4239.532296]  btrfs_file_write_iter+0x2bb/0x5f4
[ 4239.532491]  aio_write+0xe2/0x180
[ 4239.532669]  ? lock_acquire+0xac/0x1e0
[ 4239.532839]  ? __might_fault+0x3e/0x90
[ 4239.533032]  do_io_submit+0x594/0x860
[ 4239.533223]  ? do_io_submit+0x594/0x860
[ 4239.533398]  SyS_io_submit+0x10/0x20
[ 4239.533560]  ? SyS_io_submit+0x10/0x20
[ 4239.533729]  do_syscall_64+0x75/0x1d0
[ 4239.533979]  entry_SYSCALL_64_after_hwframe+0x42/0xb7
[ 4239.534182] RIP: 0033:0x7f8519741697

The problem here is, at btree_read_extent_buffer_pages() we don't have
acquired read/write lock on that extent buffer, only basic info like
level/bytenr is reliable.

So race condition leads to such false alert.

However in current call site, it's impossible to acquire proper lock
without race window.
To fix the problem, we only verify first key for committed tree blocks
(whose generation is no larger than fs_info->last_trans_committed), so
the content of such tree blocks will not change and there is no need to
get read/write lock.

Reported-by: Nikolay Borisov <nborisov@suse.com>
Fixes: 581c176041 ("btrfs: Validate child tree block's level and first key")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-13 16:16:15 +02:00
David Sterba
852eb3aeea btrfs: add SPDX header to Kconfig
Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-12 16:29:55 +02:00
David Sterba
c1d7c514f7 btrfs: replace GPL boilerplate by SPDX -- sources
Remove GPL boilerplate text (long, short, one-line) and keep the rest,
ie. personal, company or original source copyright statements. Add the
SPDX header.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-12 16:29:51 +02:00
David Sterba
9888c3402c btrfs: replace GPL boilerplate by SPDX -- headers
Remove GPL boilerplate text (long, short, one-line) and keep the rest,
ie. personal, company or original source copyright statements. Add the
SPDX header.

Unify the include protection macros to match the file names.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-12 16:29:46 +02:00
Filipe Manana
471d557afe Btrfs: fix loss of prealloc extents past i_size after fsync log replay
Currently if we allocate extents beyond an inode's i_size (through the
fallocate system call) and then fsync the file, we log the extents but
after a power failure we replay them and then immediately drop them.
This behaviour happens since about 2009, commit c71bf099ab ("Btrfs:
Avoid orphan inodes cleanup while replaying log"), because it marks
the inode as an orphan instead of dropping any extents beyond i_size
before replaying logged extents, so after the log replay, and while
the mount operation is still ongoing, we find the inode marked as an
orphan and then perform a truncation (drop extents beyond the inode's
i_size). Because the processing of orphan inodes is still done
right after replaying the log and before the mount operation finishes,
the intention of that commit does not make any sense (at least as
of today). However reverting that behaviour is not enough, because
we can not simply discard all extents beyond i_size and then replay
logged extents, because we risk dropping extents beyond i_size created
in past transactions, for example:

  add prealloc extent beyond i_size
  fsync - clears the flag BTRFS_INODE_NEEDS_FULL_SYNC from the inode
  transaction commit
  add another prealloc extent beyond i_size
  fsync - triggers the fast fsync path
  power failure

In that scenario, we would drop the first extent and then replay the
second one. To fix this just make sure that all prealloc extents
beyond i_size are logged, and if we find too many (which is far from
a common case), fallback to a full transaction commit (like we do when
logging regular extents in the fast fsync path).

Trivial reproducer:

 $ mkfs.btrfs -f /dev/sdb
 $ mount /dev/sdb /mnt
 $ xfs_io -f -c "pwrite -S 0xab 0 256K" /mnt/foo
 $ sync
 $ xfs_io -c "falloc -k 256K 1M" /mnt/foo
 $ xfs_io -c "fsync" /mnt/foo
 <power failure>

 # mount to replay log
 $ mount /dev/sdb /mnt
 # at this point the file only has one extent, at offset 0, size 256K

A test case for fstests follows soon, covering multiple scenarios that
involve adding prealloc extents with previous shrinking truncates and
without such truncates.

Fixes: c71bf099ab ("Btrfs: Avoid orphan inodes cleanup while replaying log")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-12 14:50:36 +02:00
Liu Bo
af72273381 Btrfs: clean up resources during umount after trans is aborted
Currently if some fatal errors occur, like all IO get -EIO, resources
would be cleaned up when
a) transaction is being committed or
b) BTRFS_FS_STATE_ERROR is set

However, in some rare cases, resources may be left alone after transaction
gets aborted and umount may run into some ASSERT(), e.g.
ASSERT(list_empty(&block_group->dirty_list));

For case a), in btrfs_commit_transaciton(), there're several places at the
beginning where we just call btrfs_end_transaction() without cleaning up
resources.  For case b), it is possible that the trans handle doesn't have
any dirty stuff, then only trans hanlde is marked as aborted while
BTRFS_FS_STATE_ERROR is not set, so resources remain in memory.

This makes btrfs also check BTRFS_FS_STATE_TRANS_ABORTED to make sure that
all resources won't stay in memory after umount.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-12 14:49:47 +02:00
Matthew Wilcox
b93b016313 page cache: use xa_lock
Remove the address_space ->tree_lock and use the xa_lock newly added to
the radix_tree_root.  Rename the address_space ->page_tree to ->i_pages,
since we don't really care that it's a tree.

[willy@infradead.org: fix nds32, fs/dax.c]
  Link: http://lkml.kernel.org/r/20180406145415.GB20605@bombadil.infradead.orgLink: http://lkml.kernel.org/r/20180313132639.17387-9-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:39 -07:00
Nikolay Borisov
1e1c50a929 btrfs: Fix possible softlock on single core machines
do_chunk_alloc implements a loop checking whether there is a pending
chunk allocation and if so causes the caller do loop. Generally this
loop is executed only once, however testing with btrfs/072 on a single
core vm machines uncovered an extreme case where the system could loop
indefinitely. This is due to a missing cond_resched when loop which
doesn't give a chance to the previous chunk allocator finish its job.

The fix is to simply add the missing cond_resched.

Fixes: 6d74119f1a ("Btrfs: avoid taking the chunk_mutex in do_chunk_alloc")
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-05 19:22:35 +02:00
Liu Bo
b98def7ca6 Btrfs: bail out on error during replay_dir_deletes
If errors were returned by btrfs_next_leaf(), replay_dir_deletes needs
to bail out, otherwise @ret would be forced to be 0 after 'break;' and
the caller won't be aware of it.

Fixes: e02119d5a7 ("Btrfs: Add a write ahead tree log to optimize synchronous operations")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-05 19:22:26 +02:00
Liu Bo
80c0b4210a Btrfs: fix NULL pointer dereference in log_dir_items
0, 1 and <0 can be returned by btrfs_next_leaf(), and when <0 is
returned, path->nodes[0] could be NULL, log_dir_items lacks such a
check for <0 and we may run into a null pointer dereference panic.

Fixes: e02119d5a7 ("Btrfs: Add a write ahead tree log to optimize synchronous operations")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-05 19:22:17 +02:00
Linus Torvalds
94514bbe9e for-4.17-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAlrDg0UACgkQxWXV+ddt
 WDvtOQ//QCk0zH2EcPQnqOW6HqAfkkDc7D9P51sK1izNM3vBEYtbuPlY6wp3xnJr
 0hbPjGNU7vMC/4SIwSgEdXyAvlpOr1gm9n+w1GcxpkjLa8l4P+2wt9OX0BSzRUMu
 X7LQxqg2zmQibFy4b1MSmDGsO2dxB2eqvVUT/Ir4b56uqkdtValYRWY75APJIZ5l
 6w0Ja3HVvgOX3pVwSmadCpfMEonN4JE+mfHaP8RajAlTGQcUPq8If9w4BtEoWQRl
 QC7kUCCTmp+isnzH7u4EqEQC6XUqEqeuQH+Bli1pNYTvipHY+9EO1dSxHZoCelgk
 M9PpQz8x+N6ZMcMNtJQVifkfN6tAp/acdWBTZtlpqB8nZR4v5bBndS/5TNBMu3/v
 JfhMEsIUz5o2mWz9qUneyK80RoTRkL5SfdgOclx2Yd7K1fKuJsUjmdXaT08BzotS
 5cxTFZu7EcFJyg4eHemjdyRYr3cUkS19P2uIJle9nj3DAMpCvIyL1c1vn5eB/7MN
 3JeRME6AOQcD7sFgVNuYhGVdIBuwHU6kj4mf1WN27YKGdbsaMZsFz7/HH3SsBLOF
 E0p7Q25HcHSrAimcmLTifN+gol8Y5m6dT0Pjuf9y9QbWvHwh7oRq7DVQ3L8hJkGz
 j64b0jlv43P0QorWvsX6/VJBevWedhe1hZtrBhPFSE0CtJ3Ml4Q=
 =wkSk
 -----END PGP SIGNATURE-----

Merge tag 'for-4.17-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs updates from David Sterba:
 "There are a several user visible changes, the rest is mostly invisible
  and continues to clean up the whole code base.

  User visible changes:
   - new mount option nossd_spread (pair for ssd_spread)

   - mount option subvolid will detect junk after the number and fail
     the mount

   - add message after cancelled device replace

   - direct module dependency on libcrc32, removed own crc wrappers

   - removed user space transaction ioctls

   - use lighter locking when reading /proc/self/mounts, RCU instead of
     mutex to avoid unnecessary contention

  Enhancements:
   - skip writeback of last page when truncating file to same size

   - send: do not issue unnecessary truncate operations

   - mount option token specifiers: use %u for unsigned values, more
     validation

   - selftests: more tree block validations

  qgroups:
   - preparatory work for splitting reservation types for data and
     metadata, this should allow for more accurate tracking and fix some
     issues with underflows or do further enhancements

   - split metadata reservations for started and joined transaction so
     they do not get mixed up and are accounted correctly at commit time

   - with the above, it's possible to revert patch that potentially
     deadlocks when trying to make more space by explicitly committing
     when the quota limit is hit

   - fix root item corruption when multiple same source snapshots are
     created with quota enabled

  RAID56:
   - make sure target is identical to source when raid56 rebuild fails
     after dev-replace

   - faster rebuild during scrub, batch by stripes and not
     block-by-block

   - make more use of cached data when rebuilding from a missing device

  Fixes:
   - null pointer deref when device replace target is missing

   - fix fsync after hole punching when using no-holes feature

   - fix lockdep splat when allocating percpu data with wrong GFP flags

  Cleanups, refactoring, core changes:
   - drop redunant parameters from various functions

   - kill and opencode trivial helpers

   - __cold/__exit function annotations

   - dead code removal

   - continued audit and documentation of memory barriers

   - error handling: handle removal from uuid tree

   - error handling: remove handling of impossible condtitons

   - more debugging or error messages

   - updated tracepoints

   - one VLA use removal (and one still left)"

* tag 'for-4.17-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (164 commits)
  btrfs: lift errors from add_extent_changeset to the callers
  Btrfs: print error messages when failing to read trees
  btrfs: user proper type for btrfs_mask_flags flags
  btrfs: split dev-replace locking helpers for read and write
  btrfs: remove stale comments about fs_mutex
  btrfs: use RCU in btrfs_show_devname for device list traversal
  btrfs: update barrier in should_cow_block
  btrfs: use lockdep_assert_held for mutexes
  btrfs: use lockdep_assert_held for spinlocks
  btrfs: Validate child tree block's level and first key
  btrfs: tests/qgroup: Fix wrong tree backref level
  Btrfs: fix copy_items() return value when logging an inode
  Btrfs: fix fsync after hole punching when using no-holes feature
  btrfs: use helper to set ulist aux from a qgroup
  Revert "btrfs: qgroups: Retry after commit on getting EDQUOT"
  btrfs: qgroup: Update trace events for metadata reservation
  btrfs: qgroup: Use root::qgroup_meta_rsv_* to record qgroup meta reserved space
  btrfs: delayed-inode: Use new qgroup meta rsv for delayed inode and item
  btrfs: qgroup: Use separate meta reservation type for delalloc
  btrfs: qgroup: Introduce function to convert META_PREALLOC into META_PERTRANS
  ...
2018-04-04 13:03:38 -07:00
Linus Torvalds
ce6eba3dba Merge branch 'sched-wait-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull wait_var_event updates from Ingo Molnar:
 "This introduces the new wait_var_event() API, which is a more flexible
  waiting primitive than wait_on_atomic_t().

  All wait_on_atomic_t() users are migrated over to the new API and
  wait_on_atomic_t() is removed. The migration fixes one bug and should
  result in no functional changes for the other usecases"

* 'sched-wait-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/wait: Improve __var_waitqueue() code generation
  sched/wait: Remove the wait_on_atomic_t() API
  sched/wait, arch/mips: Fix and convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, fs/ocfs2: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, fs/nfs: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, fs/fscache: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, fs/btrfs: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, fs/afs: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, drivers/media: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, drivers/drm: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait: Introduce wait_var_event()
2018-04-02 16:50:39 -07:00
David Sterba
57599c7e77 btrfs: lift errors from add_extent_changeset to the callers
The missing error handling in add_extent_changeset was hidden, so make
it at least visible in the callers.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 02:03:25 +02:00
Liu Bo
f50f435390 Btrfs: print error messages when failing to read trees
When mount fails to read trees like fs tree, checksum tree, extent
tree, etc, there is not enough information about where went wrong.

With this, messages like

"BTRFS warning (device sdf): failed to read root (objectid=7): -5"

would help us a bit.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 02:02:14 +02:00
David Sterba
38e82de8cc btrfs: user proper type for btrfs_mask_flags flags
All users pass a local unsigned int and not the __uXX types that are
supposed to be used for userspace interfaces.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 02:01:07 +02:00
David Sterba
7e79cb86be btrfs: split dev-replace locking helpers for read and write
The current calls are unclear in what way btrfs_dev_replace_lock takes
the locks, so drop the argument, split the helpers and use similar
naming as for read and write locks.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 02:01:07 +02:00
David Sterba
e7ab0af6c3 btrfs: remove stale comments about fs_mutex
The fs_mutex has been killed in 2008, a213501153 ("Btrfs: Replace
the big fs_mutex with a collection of other locks"), still remembered in
some comments.

We don't have any extra needs for locking in the ACL handlers.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 02:01:07 +02:00
David Sterba
88c14590cd btrfs: use RCU in btrfs_show_devname for device list traversal
The show_devname callback is used to print device name in
/proc/self/mounts, we need to traverse the device list consistently and
read the name that's copied to a seq buffer so we don't need further
locking.

If the first device is being deleted at the same time, the RCU will
allow us to read the device name, though it will become stale right
after the RCU protection ends. This is unavoidable and the user can
expect that the device will disappear from the filesystem's list at some
point.

The device_list_mutex was pretty heavy as it is used eg. for writing
superblock and a few other IO related contexts. This can stall any
application that reads the proc file for no reason.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 02:01:06 +02:00
David Sterba
d1980131ca btrfs: update barrier in should_cow_block
Once there was a simple int force_cow that was used with the plain
barriers, and then converted to a bit, so we should use the appropriate
barrier helper.

Other variables in the complex if condition do not depend on a barrier,
so we should be fine in case the atomic barrier becomes a no-op.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 02:01:06 +02:00
David Sterba
a32bf9a302 btrfs: use lockdep_assert_held for mutexes
Using lockdep_assert_held is preferred, replace mutex_is_locked.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 02:01:06 +02:00
David Sterba
a4666e688f btrfs: use lockdep_assert_held for spinlocks
Using lockdep_assert_held is preferred, replace assert_spin_locked.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 02:01:06 +02:00
Qu Wenruo
581c176041 btrfs: Validate child tree block's level and first key
We have several reports about node pointer points to incorrect child
tree blocks, which could have even wrong owner and level but still with
valid generation and checksum.

Although btrfs check could handle it and print error message like:
leaf parent key incorrect 60670574592

Kernel doesn't have enough check on this type of corruption correctly.
At least add such check to read_tree_block() and btrfs_read_buffer(),
where we need two new parameters @level and @first_key to verify the
child tree block.

The new @level check is mandatory and all call sites are already
modified to extract expected level from its call chain.

While @first_key is optional, the following call sites are skipping such
check:
1) Root node/leaf
   As ROOT_ITEM doesn't contain the first key, skip @first_key check.
2) Direct backref
   Only parent bytenr and level is known and we need to resolve the key
   all by ourselves, skip @first_key check.

Another note of this verification is, it needs extra info from nodeptr
or ROOT_ITEM, so it can't fit into current tree-checker framework, which
is limited to node/leaf boundary.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 02:01:06 +02:00
Qu Wenruo
3c0efdf03b btrfs: tests/qgroup: Fix wrong tree backref level
The extent tree of the test fs is like the following:

 BTRFS info (device (null)): leaf 16327509003777336587 total ptrs 1 free space 3919
  item 0 key (4096 168 4096) itemoff 3944 itemsize 51
          extent refs 1 gen 1 flags 2
          tree block key (68719476736 0 0) level 1
                                           ^^^^^^^
          ref#0: tree block backref root 5

And it's using an empty tree for fs tree, so there is no way that its
level can be 1.

For REAL (created by mkfs) fs tree backref with no skinny metadata, the
result should look like:

 item 3 key (30408704 EXTENT_ITEM 4096) itemoff 3845 itemsize 51
         refs 1 gen 4 flags TREE_BLOCK
         tree block key (256 INODE_ITEM 0) level 0
                                           ^^^^^^^
         tree block backref root 5

Fix the level to 0, so it won't break later tree level checker.

Fixes: faa2dbf004 ("Btrfs: add sanity tests for new qgroup accounting code")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 02:01:05 +02:00
Filipe Manana
8434ec46c6 Btrfs: fix copy_items() return value when logging an inode
When logging an inode, at tree-log.c:copy_items(), if we call
btrfs_next_leaf() at the loop which checks for the need to log holes, we
need to make sure copy_items() returns the value 1 to its caller and
not 0 (on success). This is because the path the caller passed was
released and is now different from what is was before, and the caller
expects a return value of 0 to mean both success and that the path
has not changed, while a return value of 1 means both success and
signals the caller that it can not reuse the path, it has to perform
another tree search.

Even though this is a case that should not be triggered on normal
circumstances or very rare at least, its consequences can be very
unpredictable (especially when replaying a log tree).

Fixes: 16e7549f04 ("Btrfs: incompatible format change to remove hole extents")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 02:01:05 +02:00
Filipe Manana
4ee3fad34a Btrfs: fix fsync after hole punching when using no-holes feature
When we have the no-holes mode enabled and fsync a file after punching a
hole in it, we can end up not logging the whole hole range in the log tree.
This happens if the file has extent items that span more than one leaf and
we punch a hole that covers a range that starts in a leaf but does not go
beyond the offset of the first extent in the next leaf.

Example:

  $ mkfs.btrfs -f -O no-holes -n 65536 /dev/sdb
  $ mount /dev/sdb /mnt
  $ for ((i = 0; i <= 831; i++)); do
	offset=$((i * 2 * 256 * 1024))
	xfs_io -f -c "pwrite -S 0xab -b 256K $offset 256K" \
		/mnt/foobar >/dev/null
    done
  $ sync

  # We now have 2 leafs in our filesystem fs tree, the first leaf has an
  # item corresponding the extent at file offset 216530944 and the second
  # leaf has a first item corresponding to the extent at offset 217055232.
  # Now we punch a hole that partially covers the range of the extent at
  # offset 216530944 but does go beyond the offset 217055232.

  $ xfs_io -c "fpunch $((216530944 + 128 * 1024 - 4000)) 256K" /mnt/foobar
  $ xfs_io -c "fsync" /mnt/foobar

  <power fail>

  # mount to replay the log
  $ mount /dev/sdb /mnt

  # Before this patch, only the subrange [216658016, 216662016[ (length of
  # 4000 bytes) was logged, leaving an incorrect file layout after log
  # replay.

Fix this by checking if there is a hole between the last extent item that
we processed and the first extent item in the next leaf, and if there is
one, log an explicit hole extent item.

Fixes: 16e7549f04 ("Btrfs: incompatible format change to remove hole extents")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 02:01:05 +02:00
David Sterba
a1840b5023 btrfs: use helper to set ulist aux from a qgroup
We have a nice helper to do proper casting of a qgroup to a ulist aux
value. And several places that could make use of it.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 02:01:05 +02:00
Qu Wenruo
0b78877a2a Revert "btrfs: qgroups: Retry after commit on getting EDQUOT"
This reverts commit 48a89bc4f2.

The idea to commit transaction and free some space after hitting qgroup
limit is good, although the problem is it can easily cause deadlocks.

One deadlock example is caused by trying to flush data while still
holding it:

Call Trace:
 __schedule+0x49d/0x10f0
 schedule+0xc6/0x290
 schedule_timeout+0x187/0x1c0
 wait_for_completion+0x204/0x3a0
 btrfs_wait_ordered_extents+0xa40/0xaf0 [btrfs]
 qgroup_reserve+0x913/0xa10 [btrfs]
 btrfs_qgroup_reserve_data+0x3ef/0x580 [btrfs]
 btrfs_check_data_free_space+0x96/0xd0 [btrfs]
 __btrfs_buffered_write+0x3ac/0xd40 [btrfs]
 btrfs_file_write_iter+0x62a/0xba0 [btrfs]
 __vfs_write+0x320/0x430
 vfs_write+0x107/0x270
 SyS_write+0xbf/0x150
 do_syscall_64+0x1b0/0x3d0
 entry_SYSCALL64_slow_path+0x25/0x25

Another can be caused by trying to commit one transaction while nesting
with trans handle held by ourselves:

btrfs_start_transaction()
|- btrfs_qgroup_reserve_meta_pertrans()
   |- qgroup_reserve()
      |- btrfs_join_transaction()
      |- btrfs_commit_transaction()

The retry is causing more problems than exppected when limit is enabled.
At least a graceful EDQUOT is way better than deadlock.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 02:01:05 +02:00
Qu Wenruo
4ee0d8832c btrfs: qgroup: Update trace events for metadata reservation
Now trace_qgroup_meta_reserve() will have extra type parameter.

And introduce two new trace events:

1) trace_qgroup_meta_free_all_pertrans()
   For btrfs_qgroup_free_meta_all_pertrans()

2) trace_qgroup_meta_convert()
   For btrfs_qgroup_convert_reserved_meta()

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 02:01:05 +02:00
Qu Wenruo
8287475a20 btrfs: qgroup: Use root::qgroup_meta_rsv_* to record qgroup meta reserved space
For quota disabled->enable case, it's possible that at reservation time
quota was not enabled so no bytes were really reserved, while at release
time, quota was enabled so we will try to release some bytes we didn't
really own.

Such situation can cause metadata reserveation underflow, for both types,
also less possible for per-trans type since quota enable will commit
transaction.

To address this, record qgroup meta reserved bytes into
root::qgroup_meta_rsv_pertrans and ::prealloc.
So at releasing time we won't free any bytes we didn't reserve.

For DATA, it's already handled by io_tree, so nothing needs to be done
there.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 02:01:04 +02:00
Qu Wenruo
4f5427ccce btrfs: delayed-inode: Use new qgroup meta rsv for delayed inode and item
Quite similar for delalloc, some modification to delayed-inode and
delayed-item reservation.  Also needs extra parameter for release case
to distinguish normal release and error release.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 02:01:03 +02:00
Qu Wenruo
43b18595d6 btrfs: qgroup: Use separate meta reservation type for delalloc
Before this patch, btrfs qgroup is mixing per-transcation meta rsv with
preallocated meta rsv, making it quite easy to underflow qgroup meta
reservation.

Since we have the new qgroup meta rsv types, apply it to delalloc
reservation.

Now for delalloc, most of its reserved space will use META_PREALLOC qgroup
rsv type.

And for callers reducing outstanding extent like btrfs_finish_ordered_io(),
they will convert corresponding META_PREALLOC reservation to
META_PERTRANS.

This is mainly due to the fact that current qgroup numbers will only be
updated in btrfs_commit_transaction(), that's to say if we don't keep
such placeholder reservation, we can exceed qgroup limitation.

And for callers freeing outstanding extent in error handler, we will
just free META_PREALLOC bytes.

This behavior makes callers of btrfs_qgroup_release_meta() or
btrfs_qgroup_convert_meta() to be aware of which type they are.
So in this patch, btrfs_delalloc_release_metadata() and its callers get
an extra parameter to info qgroup to do correct meta convert/release.

The good news is, even we use the wrong type (convert or free), it won't
cause obvious bug, as prealloc type is always in good shape, and the
type only affects how per-trans meta is increased or not.

So the worst case will be at most metadata limitation can be sometimes
exceeded (no convert at all) or metadata limitation is reached too soon
(no free at all).

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:14 +02:00
Qu Wenruo
64cfaef636 btrfs: qgroup: Introduce function to convert META_PREALLOC into META_PERTRANS
For meta_prealloc reservation users, after btrfs_join_transaction()
caller will modify tree so part (or even all) meta_prealloc reservation
should be converted to meta_pertrans until transaction commit time.

This patch introduces a new function,
btrfs_qgroup_convert_reserved_meta() to do this for META_PREALLOC
reservation user.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:14 +02:00
Qu Wenruo
e1211d0e89 btrfs: qgroup: Don't use root->qgroup_meta_rsv for qgroup
Since qgroup has seperate metadata reservation types now, we can
completely get rid of the old root->qgroup_meta_rsv, which mostly acts
as current META_PERTRANS reservation type.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:14 +02:00
Qu Wenruo
733e03a0b2 btrfs: qgroup: Split meta rsv type into meta_prealloc and meta_pertrans
Btrfs uses 2 different methods to reseve metadata qgroup space.

1) Reserve at btrfs_start_transaction() time
   This is quite straightforward, caller will use the trans handler
   allocated to modify b-trees.

   In this case, reserved metadata should be kept until qgroup numbers
   are updated.

2) Reserve by using block_rsv first, and later btrfs_join_transaction()
   This is more complicated, caller will reserve space using block_rsv
   first, and then later call btrfs_join_transaction() to get a trans
   handle.

   In this case, before we modify trees, the reserved space can be
   modified on demand, and after btrfs_join_transaction(), such reserved
   space should also be kept until qgroup numbers are updated.

Since these two types behave differently, split the original "META"
reservation type into 2 sub-types:

  META_PERTRANS:
    For above case 1)

  META_PREALLOC:
    For reservations that happened before btrfs_join_transaction() of
    case 2)

NOTE: This patch will only convert existing qgroup meta reservation
callers according to its situation, not ensuring all callers are at
correct timing.
Such fix will be added in later patches.

Signed-off-by: Qu Wenruo <wqu@suse.com>
[ update comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:14 +02:00
Qu Wenruo
5c40507ffb btrfs: qgroup: Cleanup the remaining old reservation counters
So qgroup is switched to new separate types reservation system.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:13 +02:00
Qu Wenruo
64ee4e751a btrfs: qgroup: Update trace events to use new separate rsv types
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:13 +02:00
Qu Wenruo
429d6275d5 btrfs: qgroup: Fix wrong qgroup reservation update for relationship modification
When modifying qgroup relationship, for qgroup which only owns exclusive
extents, we will go through quick update path.

In this path, we will add/subtract exclusive and reference number for
parent qgroup, since the source (child) qgroup only has exclusive
extents, destination (parent) qgroup will also own or lose those extents
exclusively.

The same should be the same for reservation, since later reservation
adding/releasing will also affect parent qgroup, without the reservation
carried from child, parent will underflow reservation or have dead
reservation which will never be freed.

However original code doesn't do the same thing for reservation.
It handles qgroup reservation quite differently:

It removes qgroup reservation, as it's allocating space from the
reserved qgroup for relationship adding.
But does nothing for qgroup reservation if we're removing a qgroup
relationship.

According to the original code, it looks just like because we're adding
qgroup->rfer, the code assumes we're writing new data, so it's follows
the normal write routine, by reducing qgroup->reserved and adding
qgroup->rfer/excl.

This old behavior is wrong, and should be fixed to follow the same
excl/rfer behavior.

Just fix it by using the correct behavior described above.

Fixes: 31193213f1 ("Btrfs: qgroup: Introduce a may_use to account space_info->bytes_may_use.")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:13 +02:00
Qu Wenruo
dba213242f btrfs: qgroup: Make qgroup_reserve and its callers to use separate reservation type
Since most callers of qgroup_reserve() are already defined by type,
converting qgroup_reserve() is quite an easy work.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:13 +02:00
Qu Wenruo
f59c0347d4 btrfs: qgroup: Introduce helpers to update and access new qgroup rsv
Introduce helpers to:

1) Get total reserved space
   For limit calculation
2) Add/release reserved space for given type
   With underflow detection and warning
3) Add/release reserved space according to child qgroup

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:13 +02:00
Qu Wenruo
d4e5c92055 btrfs: qgroup: Skeleton to support separate qgroup reservation type
Instead of single qgroup->reserved, use a new structure btrfs_qgroup_rsv
to store different types of reservation.

This patch only updates the header needed to compile.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:13 +02:00
Omar Sandoval
0a0d4415e3 Btrfs: delete dead code in btrfs_orphan_add()
btrfs_orphan_add() has had this case commented out since it was first
introduced in commit d68fc57b7e ("Btrfs: Metadata reservation for
orphan inodes"). Most of the orphan cleanup code has been rewritten
since then, so it's safe to say that this code isn't needed.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
[ switch to bool ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:12 +02:00
Misono, Tomohiro
4408ea7c5f btrfs: ctree.h: Fix wrong comment position about csum size
Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:12 +02:00
Jeff Mahoney
75cb379d26 btrfs: defer adding raid type kobject until after chunk relocation
Any time the first block group of a new type is created, we add a new
kobject to sysfs to hold the attributes for that type.  Kobject-internal
allocations always use GFP_KERNEL, making them prone to fs-reclaim races.
While it appears as if this can occur any time a block group is created,
the only times the first block group of a new type can be created in
memory is at mount and when we create the first new block group during
raid conversion.

This patch adds a new list to track pending kobject additions and then
handles them after we do chunk relocation.  Between relocating the
target chunk (or forcing allocation of a new chunk in the case of data)
and removing the old chunk, we're in a safe place for fs-reclaim to
occur.  We're holding the volume mutex, which is already held across
page faults, and the delete_unused_bgs_mutex, which will only stall
the cleaner thread.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:12 +02:00
Jeff Mahoney
dc2d3005d2 btrfs: remove dead create_space_info calls
Since commit 2be12ef79 (btrfs: Separate space_info create/update), we've
separated out the creation and updating of the space info structures.
That commit was a straightforward refactoring of the two parts of
update_space_info, but we can go a step further.  Since commits
c59021f84 (Btrfs: fix OOPS of empty filesystem after balance) and
b742bb82f (Btrfs: Link block groups of different raid types), we know
that the space_info structures will be created at mount and there will
only ever be, at most, three of them.

This patch cleans out the create_space_info calls after __find_space_info
returns NULL since __find_space_info *can't* return NULL.

The initial cause for reviewing this was the kobject_add calls from
create_space_info occuring in sites where fs-reclaim wasn't allowed.  Now
we are certain they occur only early in the mount process and are safe.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:12 +02:00
Liu Bo
580c6efaf9 Btrfs: replace: cache rbio when rebuild data on missing device
Rebuild on missing device is as same as recover, after it's done, rbio
has data which is consistent with on-disk data, so it can be cached to
avoid further reads.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:12 +02:00
Jeff Mahoney
8a5a916d9a btrfs: fix lockdep splat in btrfs_alloc_subvolume_writers
While running btrfs/011, I hit the following lockdep splat.

This is the important bit:
   pcpu_alloc+0x1ac/0x5e0
   __percpu_counter_init+0x4e/0xb0
   btrfs_init_fs_root+0x99/0x1c0 [btrfs]
   btrfs_get_fs_root.part.54+0x5b/0x150 [btrfs]
   resolve_indirect_refs+0x130/0x830 [btrfs]
   find_parent_nodes+0x69e/0xff0 [btrfs]
   btrfs_find_all_roots_safe+0xa0/0x110 [btrfs]
   btrfs_find_all_roots+0x50/0x70 [btrfs]
   btrfs_qgroup_prepare_account_extents+0x53/0x90 [btrfs]
   btrfs_commit_transaction+0x3ce/0x9b0 [btrfs]

The percpu_counter_init call in btrfs_alloc_subvolume_writers
uses GFP_KERNEL, which we can't do during transaction commit.

This switches it to GFP_NOFS.

========================================================
WARNING: possible irq lock inversion dependency detected
4.12.14-kvmsmall #8 Tainted: G        W
--------------------------------------------------------
kswapd0/50 just changed the state of lock:
 (&delayed_node->mutex){+.+.-.}, at: [<ffffffffc06994fa>] __btrfs_release_delayed_node+0x3a/0x1f0 [btrfs]
but this lock took another, RECLAIM_FS-unsafe lock in the past:
 (pcpu_alloc_mutex){+.+.+.}

and interrupts could create inverse lock ordering between them.

other info that might help us debug this:
Chain exists of:
  &delayed_node->mutex --> &found->groups_sem --> pcpu_alloc_mutex

 Possible interrupt unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(pcpu_alloc_mutex);
                               local_irq_disable();
                               lock(&delayed_node->mutex);
                               lock(&found->groups_sem);
  <Interrupt>
    lock(&delayed_node->mutex);

 *** DEADLOCK ***

2 locks held by kswapd0/50:
 #0:  (shrinker_rwsem){++++..}, at: [<ffffffff811dc11f>] shrink_slab+0x7f/0x5b0
 #1:  (&type->s_umount_key#30){+++++.}, at: [<ffffffff8126dec6>] trylock_super+0x16/0x50

the shortest dependencies between 2nd lock and 1st lock:
   -> (pcpu_alloc_mutex){+.+.+.} ops: 4904 {
      HARDIRQ-ON-W at:
                          __mutex_lock+0x4e/0x8c0
                          pcpu_alloc+0x1ac/0x5e0
                          alloc_kmem_cache_cpus.isra.70+0x25/0xa0
                          __do_tune_cpucache+0x2c/0x220
                          do_tune_cpucache+0x26/0xc0
                          enable_cpucache+0x6d/0xf0
                          kmem_cache_init_late+0x42/0x75
                          start_kernel+0x343/0x4cb
                          x86_64_start_kernel+0x127/0x134
                          secondary_startup_64+0xa5/0xb0
      SOFTIRQ-ON-W at:
                          __mutex_lock+0x4e/0x8c0
                          pcpu_alloc+0x1ac/0x5e0
                          alloc_kmem_cache_cpus.isra.70+0x25/0xa0
                          __do_tune_cpucache+0x2c/0x220
                          do_tune_cpucache+0x26/0xc0
                          enable_cpucache+0x6d/0xf0
                          kmem_cache_init_late+0x42/0x75
                          start_kernel+0x343/0x4cb
                          x86_64_start_kernel+0x127/0x134
                          secondary_startup_64+0xa5/0xb0
      RECLAIM_FS-ON-W at:
                             __kmalloc+0x47/0x310
                             pcpu_extend_area_map+0x2b/0xc0
                             pcpu_alloc+0x3ec/0x5e0
                             alloc_kmem_cache_cpus.isra.70+0x25/0xa0
                             __do_tune_cpucache+0x2c/0x220
                             do_tune_cpucache+0x26/0xc0
                             enable_cpucache+0x6d/0xf0
                             __kmem_cache_create+0x1bf/0x390
                             create_cache+0xba/0x1b0
                             kmem_cache_create+0x1f8/0x2b0
                             ksm_init+0x6f/0x19d
                             do_one_initcall+0x50/0x1b0
                             kernel_init_freeable+0x201/0x289
                             kernel_init+0xa/0x100
                             ret_from_fork+0x3a/0x50
      INITIAL USE at:
                         __mutex_lock+0x4e/0x8c0
                         pcpu_alloc+0x1ac/0x5e0
                         alloc_kmem_cache_cpus.isra.70+0x25/0xa0
                         setup_cpu_cache+0x2f/0x1f0
                         __kmem_cache_create+0x1bf/0x390
                         create_boot_cache+0x8b/0xb1
                         kmem_cache_init+0xa1/0x19e
                         start_kernel+0x270/0x4cb
                         x86_64_start_kernel+0x127/0x134
                         secondary_startup_64+0xa5/0xb0
    }
    ... key      at: [<ffffffff821d8e70>] pcpu_alloc_mutex+0x70/0xa0
    ... acquired at:
   pcpu_alloc+0x1ac/0x5e0
   __percpu_counter_init+0x4e/0xb0
   btrfs_init_fs_root+0x99/0x1c0 [btrfs]
   btrfs_get_fs_root.part.54+0x5b/0x150 [btrfs]
   resolve_indirect_refs+0x130/0x830 [btrfs]
   find_parent_nodes+0x69e/0xff0 [btrfs]
   btrfs_find_all_roots_safe+0xa0/0x110 [btrfs]
   btrfs_find_all_roots+0x50/0x70 [btrfs]
   btrfs_qgroup_prepare_account_extents+0x53/0x90 [btrfs]
   btrfs_commit_transaction+0x3ce/0x9b0 [btrfs]
   transaction_kthread+0x176/0x1b0 [btrfs]
   kthread+0x102/0x140
   ret_from_fork+0x3a/0x50

  -> (&fs_info->commit_root_sem){++++..} ops: 1566382 {
     HARDIRQ-ON-W at:
                        down_write+0x3e/0xa0
                        cache_block_group+0x287/0x420 [btrfs]
                        find_free_extent+0x106c/0x12d0 [btrfs]
                        btrfs_reserve_extent+0xd8/0x170 [btrfs]
                        cow_file_range.isra.66+0x133/0x470 [btrfs]
                        run_delalloc_range+0x121/0x410 [btrfs]
                        writepage_delalloc.isra.50+0xfe/0x180 [btrfs]
                        __extent_writepage+0x19a/0x360 [btrfs]
                        extent_write_cache_pages.constprop.56+0x249/0x3e0 [btrfs]
                        extent_writepages+0x4d/0x60 [btrfs]
                        do_writepages+0x1a/0x70
                        __filemap_fdatawrite_range+0xa7/0xe0
                        btrfs_rename+0x5ee/0xdb0 [btrfs]
                        vfs_rename+0x52a/0x7e0
                        SyS_rename+0x351/0x3b0
                        do_syscall_64+0x79/0x1e0
                        entry_SYSCALL_64_after_hwframe+0x42/0xb7
     HARDIRQ-ON-R at:
                        down_read+0x35/0x90
                        caching_thread+0x57/0x560 [btrfs]
                        normal_work_helper+0x1c0/0x5e0 [btrfs]
                        process_one_work+0x1e0/0x5c0
                        worker_thread+0x44/0x390
                        kthread+0x102/0x140
                        ret_from_fork+0x3a/0x50
     SOFTIRQ-ON-W at:
                        down_write+0x3e/0xa0
                        cache_block_group+0x287/0x420 [btrfs]
                        find_free_extent+0x106c/0x12d0 [btrfs]
                        btrfs_reserve_extent+0xd8/0x170 [btrfs]
                        cow_file_range.isra.66+0x133/0x470 [btrfs]
                        run_delalloc_range+0x121/0x410 [btrfs]
                        writepage_delalloc.isra.50+0xfe/0x180 [btrfs]
                        __extent_writepage+0x19a/0x360 [btrfs]
                        extent_write_cache_pages.constprop.56+0x249/0x3e0 [btrfs]
                        extent_writepages+0x4d/0x60 [btrfs]
                        do_writepages+0x1a/0x70
                        __filemap_fdatawrite_range+0xa7/0xe0
                        btrfs_rename+0x5ee/0xdb0 [btrfs]
                        vfs_rename+0x52a/0x7e0
                        SyS_rename+0x351/0x3b0
                        do_syscall_64+0x79/0x1e0
                        entry_SYSCALL_64_after_hwframe+0x42/0xb7
     SOFTIRQ-ON-R at:
                        down_read+0x35/0x90
                        caching_thread+0x57/0x560 [btrfs]
                        normal_work_helper+0x1c0/0x5e0 [btrfs]
                        process_one_work+0x1e0/0x5c0
                        worker_thread+0x44/0x390
                        kthread+0x102/0x140
                        ret_from_fork+0x3a/0x50
     INITIAL USE at:
                       down_write+0x3e/0xa0
                       cache_block_group+0x287/0x420 [btrfs]
                       find_free_extent+0x106c/0x12d0 [btrfs]
                       btrfs_reserve_extent+0xd8/0x170 [btrfs]
                       cow_file_range.isra.66+0x133/0x470 [btrfs]
                       run_delalloc_range+0x121/0x410 [btrfs]
                       writepage_delalloc.isra.50+0xfe/0x180 [btrfs]
                       __extent_writepage+0x19a/0x360 [btrfs]
                       extent_write_cache_pages.constprop.56+0x249/0x3e0 [btrfs]
                       extent_writepages+0x4d/0x60 [btrfs]
                       do_writepages+0x1a/0x70
                       __filemap_fdatawrite_range+0xa7/0xe0
                       btrfs_rename+0x5ee/0xdb0 [btrfs]
                       vfs_rename+0x52a/0x7e0
                       SyS_rename+0x351/0x3b0
                       do_syscall_64+0x79/0x1e0
                       entry_SYSCALL_64_after_hwframe+0x42/0xb7
   }
   ... key      at: [<ffffffffc0729578>] __key.61970+0x0/0xfffffffffff9aa88 [btrfs]
   ... acquired at:
   cache_block_group+0x287/0x420 [btrfs]
   find_free_extent+0x106c/0x12d0 [btrfs]
   btrfs_reserve_extent+0xd8/0x170 [btrfs]
   btrfs_alloc_tree_block+0x12f/0x4c0 [btrfs]
   btrfs_create_tree+0xbb/0x2a0 [btrfs]
   btrfs_create_uuid_tree+0x37/0x140 [btrfs]
   open_ctree+0x23c0/0x2660 [btrfs]
   btrfs_mount+0xd36/0xf90 [btrfs]
   mount_fs+0x3a/0x160
   vfs_kern_mount+0x66/0x150
   btrfs_mount+0x18c/0xf90 [btrfs]
   mount_fs+0x3a/0x160
   vfs_kern_mount+0x66/0x150
   do_mount+0x1c1/0xcc0
   SyS_mount+0x7e/0xd0
   do_syscall_64+0x79/0x1e0
   entry_SYSCALL_64_after_hwframe+0x42/0xb7

 -> (&found->groups_sem){++++..} ops: 2134587 {
    HARDIRQ-ON-W at:
                      down_write+0x3e/0xa0
                      __link_block_group+0x34/0x130 [btrfs]
                      btrfs_read_block_groups+0x33d/0x7b0 [btrfs]
                      open_ctree+0x2054/0x2660 [btrfs]
                      btrfs_mount+0xd36/0xf90 [btrfs]
                      mount_fs+0x3a/0x160
                      vfs_kern_mount+0x66/0x150
                      btrfs_mount+0x18c/0xf90 [btrfs]
                      mount_fs+0x3a/0x160
                      vfs_kern_mount+0x66/0x150
                      do_mount+0x1c1/0xcc0
                      SyS_mount+0x7e/0xd0
                      do_syscall_64+0x79/0x1e0
                      entry_SYSCALL_64_after_hwframe+0x42/0xb7
    HARDIRQ-ON-R at:
                      down_read+0x35/0x90
                      btrfs_calc_num_tolerated_disk_barrier_failures+0x113/0x1f0 [btrfs]
                      open_ctree+0x207b/0x2660 [btrfs]
                      btrfs_mount+0xd36/0xf90 [btrfs]
                      mount_fs+0x3a/0x160
                      vfs_kern_mount+0x66/0x150
                      btrfs_mount+0x18c/0xf90 [btrfs]
                      mount_fs+0x3a/0x160
                      vfs_kern_mount+0x66/0x150
                      do_mount+0x1c1/0xcc0
                      SyS_mount+0x7e/0xd0
                      do_syscall_64+0x79/0x1e0
                      entry_SYSCALL_64_after_hwframe+0x42/0xb7
    SOFTIRQ-ON-W at:
                      down_write+0x3e/0xa0
                      __link_block_group+0x34/0x130 [btrfs]
                      btrfs_read_block_groups+0x33d/0x7b0 [btrfs]
                      open_ctree+0x2054/0x2660 [btrfs]
                      btrfs_mount+0xd36/0xf90 [btrfs]
                      mount_fs+0x3a/0x160
                      vfs_kern_mount+0x66/0x150
                      btrfs_mount+0x18c/0xf90 [btrfs]
                      mount_fs+0x3a/0x160
                      vfs_kern_mount+0x66/0x150
                      do_mount+0x1c1/0xcc0
                      SyS_mount+0x7e/0xd0
                      do_syscall_64+0x79/0x1e0
                      entry_SYSCALL_64_after_hwframe+0x42/0xb7
    SOFTIRQ-ON-R at:
                      down_read+0x35/0x90
                      btrfs_calc_num_tolerated_disk_barrier_failures+0x113/0x1f0 [btrfs]
                      open_ctree+0x207b/0x2660 [btrfs]
                      btrfs_mount+0xd36/0xf90 [btrfs]
                      mount_fs+0x3a/0x160
                      vfs_kern_mount+0x66/0x150
                      btrfs_mount+0x18c/0xf90 [btrfs]
                      mount_fs+0x3a/0x160
                      vfs_kern_mount+0x66/0x150
                      do_mount+0x1c1/0xcc0
                      SyS_mount+0x7e/0xd0
                      do_syscall_64+0x79/0x1e0
                      entry_SYSCALL_64_after_hwframe+0x42/0xb7
    INITIAL USE at:
                     down_write+0x3e/0xa0
                     __link_block_group+0x34/0x130 [btrfs]
                     btrfs_read_block_groups+0x33d/0x7b0 [btrfs]
                     open_ctree+0x2054/0x2660 [btrfs]
                     btrfs_mount+0xd36/0xf90 [btrfs]
                     mount_fs+0x3a/0x160
                     vfs_kern_mount+0x66/0x150
                     btrfs_mount+0x18c/0xf90 [btrfs]
                     mount_fs+0x3a/0x160
                     vfs_kern_mount+0x66/0x150
                     do_mount+0x1c1/0xcc0
                     SyS_mount+0x7e/0xd0
                     do_syscall_64+0x79/0x1e0
                     entry_SYSCALL_64_after_hwframe+0x42/0xb7
  }
  ... key      at: [<ffffffffc0729488>] __key.59101+0x0/0xfffffffffff9ab78 [btrfs]
  ... acquired at:
   find_free_extent+0xcb4/0x12d0 [btrfs]
   btrfs_reserve_extent+0xd8/0x170 [btrfs]
   btrfs_alloc_tree_block+0x12f/0x4c0 [btrfs]
   __btrfs_cow_block+0x110/0x5b0 [btrfs]
   btrfs_cow_block+0xd7/0x290 [btrfs]
   btrfs_search_slot+0x1f6/0x960 [btrfs]
   btrfs_lookup_inode+0x2a/0x90 [btrfs]
   __btrfs_update_delayed_inode+0x65/0x210 [btrfs]
   btrfs_commit_inode_delayed_inode+0x121/0x130 [btrfs]
   btrfs_evict_inode+0x3fe/0x6a0 [btrfs]
   evict+0xc4/0x190
   __dentry_kill+0xbf/0x170
   dput+0x2ae/0x2f0
   SyS_rename+0x2a6/0x3b0
   do_syscall_64+0x79/0x1e0
   entry_SYSCALL_64_after_hwframe+0x42/0xb7

-> (&delayed_node->mutex){+.+.-.} ops: 5580204 {
   HARDIRQ-ON-W at:
                    __mutex_lock+0x4e/0x8c0
                    btrfs_delayed_update_inode+0x46/0x6e0 [btrfs]
                    btrfs_update_inode+0x83/0x110 [btrfs]
                    btrfs_dirty_inode+0x62/0xe0 [btrfs]
                    touch_atime+0x8c/0xb0
                    do_generic_file_read+0x818/0xb10
                    __vfs_read+0xdc/0x150
                    vfs_read+0x8a/0x130
                    SyS_read+0x45/0xa0
                    do_syscall_64+0x79/0x1e0
                    entry_SYSCALL_64_after_hwframe+0x42/0xb7
   SOFTIRQ-ON-W at:
                    __mutex_lock+0x4e/0x8c0
                    btrfs_delayed_update_inode+0x46/0x6e0 [btrfs]
                    btrfs_update_inode+0x83/0x110 [btrfs]
                    btrfs_dirty_inode+0x62/0xe0 [btrfs]
                    touch_atime+0x8c/0xb0
                    do_generic_file_read+0x818/0xb10
                    __vfs_read+0xdc/0x150
                    vfs_read+0x8a/0x130
                    SyS_read+0x45/0xa0
                    do_syscall_64+0x79/0x1e0
                    entry_SYSCALL_64_after_hwframe+0x42/0xb7
   IN-RECLAIM_FS-W at:
                       __mutex_lock+0x4e/0x8c0
                       __btrfs_release_delayed_node+0x3a/0x1f0 [btrfs]
                       btrfs_evict_inode+0x22c/0x6a0 [btrfs]
                       evict+0xc4/0x190
                       dispose_list+0x35/0x50
                       prune_icache_sb+0x42/0x50
                       super_cache_scan+0x139/0x190
                       shrink_slab+0x262/0x5b0
                       shrink_node+0x2eb/0x2f0
                       kswapd+0x2eb/0x890
                       kthread+0x102/0x140
                       ret_from_fork+0x3a/0x50
   INITIAL USE at:
                   __mutex_lock+0x4e/0x8c0
                   btrfs_delayed_update_inode+0x46/0x6e0 [btrfs]
                   btrfs_update_inode+0x83/0x110 [btrfs]
                   btrfs_dirty_inode+0x62/0xe0 [btrfs]
                   touch_atime+0x8c/0xb0
                   do_generic_file_read+0x818/0xb10
                   __vfs_read+0xdc/0x150
                   vfs_read+0x8a/0x130
                   SyS_read+0x45/0xa0
                   do_syscall_64+0x79/0x1e0
                   entry_SYSCALL_64_after_hwframe+0x42/0xb7
 }
 ... key      at: [<ffffffffc072d488>] __key.56935+0x0/0xfffffffffff96b78 [btrfs]
 ... acquired at:
   __lock_acquire+0x264/0x11c0
   lock_acquire+0xbd/0x1e0
   __mutex_lock+0x4e/0x8c0
   __btrfs_release_delayed_node+0x3a/0x1f0 [btrfs]
   btrfs_evict_inode+0x22c/0x6a0 [btrfs]
   evict+0xc4/0x190
   dispose_list+0x35/0x50
   prune_icache_sb+0x42/0x50
   super_cache_scan+0x139/0x190
   shrink_slab+0x262/0x5b0
   shrink_node+0x2eb/0x2f0
   kswapd+0x2eb/0x890
   kthread+0x102/0x140
   ret_from_fork+0x3a/0x50

stack backtrace:
CPU: 1 PID: 50 Comm: kswapd0 Tainted: G        W        4.12.14-kvmsmall #8 SLE15 (unreleased)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014
Call Trace:
 dump_stack+0x78/0xb7
 print_irq_inversion_bug.part.38+0x19f/0x1aa
 check_usage_forwards+0x102/0x120
 ? ret_from_fork+0x3a/0x50
 ? check_usage_backwards+0x110/0x110
 mark_lock+0x16c/0x270
 __lock_acquire+0x264/0x11c0
 ? pagevec_lookup_entries+0x1a/0x30
 ? truncate_inode_pages_range+0x2b3/0x7f0
 lock_acquire+0xbd/0x1e0
 ? __btrfs_release_delayed_node+0x3a/0x1f0 [btrfs]
 __mutex_lock+0x4e/0x8c0
 ? __btrfs_release_delayed_node+0x3a/0x1f0 [btrfs]
 ? __btrfs_release_delayed_node+0x3a/0x1f0 [btrfs]
 ? btrfs_evict_inode+0x1f6/0x6a0 [btrfs]
 __btrfs_release_delayed_node+0x3a/0x1f0 [btrfs]
 btrfs_evict_inode+0x22c/0x6a0 [btrfs]
 evict+0xc4/0x190
 dispose_list+0x35/0x50
 prune_icache_sb+0x42/0x50
 super_cache_scan+0x139/0x190
 shrink_slab+0x262/0x5b0
 shrink_node+0x2eb/0x2f0
 kswapd+0x2eb/0x890
 kthread+0x102/0x140
 ? mem_cgroup_shrink_node+0x2c0/0x2c0
 ? kthread_create_on_node+0x40/0x40
 ret_from_fork+0x3a/0x50

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:11 +02:00
Anand Jain
8ba0ae7821 btrfs: drop optimal argument from find_live_mirror()
Drop optimal argument from the function find_live_mirror() as we can
deduce it in the function itself. Also rename optimal to
preferred_mirror.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:11 +02:00
Anand Jain
99f92a7c1e btrfs: drop num argument from find_live_mirror()
Obtain the stripes info from the map directly and so no need
to pass it as an argument.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:11 +02:00
Nikolay Borisov
0a1e458a1e btrfs: Drop fs_info parameter from __btrfs_run_delayed_refs
It's provided by transaction handle.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:11 +02:00
Nikolay Borisov
5ead2dd02c btrfs: Drop fs_info parameter from btrfs_finish_extent_commit
It's provided by the transaction handle.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:11 +02:00
Nikolay Borisov
460fb20a4b btrfs: Drop fs_info parameter from btrfs_qgroup_account_extents
It's provided by the transaction handle.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:10 +02:00
Nikolay Borisov
c79a70b133 btrfs: drop fs_info parameter from btrfs_run_delayed_refs
It's provided by the transaction handle.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:10 +02:00
Nikolay Borisov
39d7d09dc2 btrfs: Remove unused flush var in shrink_delalloc
Added by 08e007d2e5 ("Btrfs: improve the noflush reservation") and
made redundant by 17024ad0a0 ("Btrfs: fix early ENOSPC due to
delalloc").

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:10 +02:00
Nikolay Borisov
101d2dc0b2 btrfs: Remove unused extent_root var from caching_thread
Added by b4570aa994 ("btrfs: fix compiling with CONFIG_BTRFS_DEBUG
enabled.") and obsoleted by 2ff7e61e0d ("btrfs: take an fs_info
directly when the root is not used otherwise").

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:41:10 +02:00
Nikolay Borisov
338dae1ae6 btrfs: remove max_active var from open_ctree
Introduced by 5cdc7ad337 ("btrfs: Replace fs_info->workers with
btrfs_workqueue.") but obsoleted by 2a4581983f ("btrfs: factor
btrfs_init_workqueues() out of open_ctree()").

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:26:57 +02:00
Nikolay Borisov
8535dc1967 btrfs: Remove unused root var from relink_file_extents
Added in 38c227d87c ("Btrfs: snapshot-aware defrag") but subsequently
made redundant by 0b246afa62 ("btrfs: root->fs_info cleanup, add
fs_info convenience variables").

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:26:57 +02:00
Nikolay Borisov
4eeb97c67a btrfs: Remove unused tot_len var from lzo_decompress
Added already unused in a6fa6fae40 ("btrfs: Add lzo compression
support").

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:26:57 +02:00
Nikolay Borisov
d6e823a578 btrfs: Remove unused length var from scrub_handle_errored_block
Added in b5d67f64f9 ("Btrfs: change scrub to support big blocks") but
rendered redundant by be50a8ddaa ("Btrfs: Simplify
scrub_setup_recheck_block()'s argument").

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:26:57 +02:00
Nikolay Borisov
a6dbceafb9 btrfs: Remove unused op_key var from add_delayed_refs
Added as part of 86d5f99442 ("btrfs: convert prelimary reference
tracking to use rbtrees") but never used. tmp_op_key essentially
subsumed that variable.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:26:57 +02:00
Qu Wenruo
ba89b80268 btrfs: volumes: Remove the meaningless condition of minimal nr_devs when allocating a chunk
When checking the minimal nr_devs, there is one dead and meaningless
condition:

if (ndevs < devs_increment * sub_stripes || ndevs < devs_min) {
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

This condition is meaningless, @devs_increment has nothing to do with
@sub_stripes.

In fact, in btrfs_raid_array[], profile with sub_stripes larger than 1
(RAID10) already has the @devs_increment set to 2.
So no need to multiple it by @sub_stripes.

And above condition is also dead.
For RAID10, @devs_increment * @sub_stripes equals 4, which is also the
@devs_min of RAID10.
For other profiles, @sub_stripes is always 1, and since @ndevs is
rounded down to @devs_increment, the condition will always be true.

Remove the meaningless condition to make later reader wander less.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:26:56 +02:00
Nikolay Borisov
6f47c706d9 btrfs: Document parameters of btrfs_reserve_extent
This function is the entry to the extent allocator and as such has
quite a number of parameters. Some of those have subtle effects on the
allocation algorithm. Document the parameters.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:26:56 +02:00
Nikolay Borisov
d87ff75863 btrfs: Handle error from btrfs_uuid_tree_rem call in _btrfs_ioctl_set_received_subvol
As with every function which deals with modifying the btree
btrfs_uuid_tree_rem can fail for any number of reasons (ie. EIO/ENOMEM).
Handle return error value from this function gracefully by aborting the
transaction.

Fixes: dd5f9615fc ("Btrfs: maintain subvolume items in the UUID tree")
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:26:56 +02:00
Nikolay Borisov
776c4a7ce8 btrfs: Use sizeof directly instead of a constant variable
The kernel would like to have all stack VLA usage removed[1].
Unfortunately using an integer constant variable as the size of an
array is still considered a VLA. Instead let's use directly sizeof(var)
which removes the VLA usage. Use the occasion to remove csum_size
altogether and use sizeof() also for the size passed to memcmp

[1]: https://lkml.org/lkml/2018/3/7/621

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31 01:26:56 +02:00