__d_lookup_done() wakes waiters on dentry->d_wait. On PREEMPT_RT we are
not allowed to do that with preemption disabled, since the wakeup
acquired wait_queue_head::lock, which is a "sleeping" spinlock on RT.
Calling it under dentry->d_lock is not a problem, since that is also a
"sleeping" spinlock on the same configs. Unfortunately, two of its
callers (__d_add() and __d_move()) are holding more than just ->d_lock
and that needs to be dealt with.
The key observation is that wakeup can be moved to any point before
dropping ->d_lock.
As a first step to solve this, move the wake up outside of the
hlist_bl_lock() held section.
This is safe because:
Waiters get inserted into ->d_wait only after they'd taken ->d_lock
and observed DCACHE_PAR_LOOKUP in flags. As long as they are
woken up (and evicted from the queue) between the moment __d_lookup_done()
has removed DCACHE_PAR_LOOKUP and dropping ->d_lock, we are safe,
since the waitqueue ->d_wait points to won't get destroyed without
having __d_lookup_done(dentry) called (under ->d_lock).
->d_wait is set only by d_alloc_parallel() and only in case when
it returns a freshly allocated in-lookup dentry. Whenever that happens,
we are guaranteed that __d_lookup_done() will be called for resulting
dentry (under ->d_lock) before the wq in question gets destroyed.
With two exceptions wq lives in call frame of the caller of
d_alloc_parallel() and we have an explicit d_lookup_done() on the
resulting in-lookup dentry before we leave that frame.
One of those exceptions is nfs_call_unlink(), where wq is embedded into
(dynamically allocated) struct nfs_unlinkdata. It is destroyed in
nfs_async_unlink_release() after an explicit d_lookup_done() on the
dentry wq went into.
Remaining exception is d_add_ci(). There wq is what we'd found in
->d_wait of d_add_ci() argument. Callers of d_add_ci() are two
instances of ->d_lookup() and they must have been given an in-lookup
dentry. Which means that they'd been called by __lookup_slow() or
lookup_open(), with wq in the call frame of one of those.
Result of d_alloc_parallel() in d_add_ci() is fed to
d_splice_alias(), which either returns non-NULL (and d_add_ci() does
d_lookup_done()) or feeds dentry to __d_add() that will do
__d_lookup_done() under ->d_lock. That concludes the analysis.
Let __d_lookup_unhash():
1) Lock the lookup hash and clear DCACHE_PAR_LOOKUP
2) Unhash the dentry
3) Retrieve and clear dentry::d_wait
4) Unlock the hash and return the retrieved waitqueue head pointer
5) Let the caller handle the wake up.
6) Rename __d_lookup_done() to __d_lookup_unhash_wake() to enforce
build failures for OOT code that used __d_lookup_done() and is not
aware of the new return value.
This does not yet solve the PREEMPT_RT problem completely because
preemption is still disabled due to i_dir_seq being held for write. This
will be addressed in subsequent steps.
An alternative solution would be to switch the waitqueue to a simple
waitqueue, but aside of Linus not being a fan of them, moving the wake up
closer to the place where dentry::lock is unlocked reduces lock contention
time for the woken up waiter.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lkml.kernel.org/r/20220613140712.77932-3-bigeasy@linutronix.de
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
i_dir_seq is a sequence counter with a lock which is represented by the
lowest bit. The writer atomically updates the counter which ensures that it
can be modified by only one writer at a time. This requires preemption to
be disabled across the write side critical section.
On !PREEMPT_RT kernels this is implicit by the caller acquiring
dentry::lock. On PREEMPT_RT kernels spin_lock() does not disable preemption
which means that a preempting writer or reader would live lock. It's
therefore required to disable preemption explicitly.
An alternative solution would be to replace i_dir_seq with a seqlock_t for
PREEMPT_RT, but that comes with its own set of problems due to arbitrary
lock nesting. A pure sequence count with an associated spinlock is not
possible because the locks held by the caller are not necessarily related.
As the critical section is small, disabling preemption is a sensible
solution.
Reported-by: Oleg.Karfich@wago.com
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lkml.kernel.org/r/20220613140712.77932-2-bigeasy@linutronix.de
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
All callers of d_alloc_parallel() must make sure that resulting
in-lookup dentry (if any) will encounter __d_lookup_done() before
the final dput(). d_add_ci() might end up creating in-lookup
dentries; they are fed to d_splice_alias(), which will normally
make sure they meet __d_lookup_done(). However, it is possible
to end up with d_splice_alias() failing with ERR_PTR(-ELOOP)
without having done so. It takes a corrupted ntfs or case-insensitive
xfs image, but neither should end up with memory corruption...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
In some cases, e.g. when size option is not specified, f_blocks, f_bavail
and f_bfree will be set to -1 instead of 0. Likewise, when nr_inodes
isn't specified, f_files and f_ffree will be set to -1 too. Update the
comment to make this clear.
Link: https://lkml.kernel.org/r/20220726142918.51693-6-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The function generic_file_buffered_read has been renamed to filemap_read
since commit 87fa0f3eb2 ("mm/filemap: rename generic_file_buffered_read
to filemap_read"). Update the corresponding comment. And duplicated
taken in hugetlbfs_fill_super is removed.
Link: https://lkml.kernel.org/r/20220726142918.51693-5-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The header file signal.h is unneeded now. Remove it.
Link: https://lkml.kernel.org/r/20220726142918.51693-4-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The forward declaration for hugetlbfs_ops is unnecessary. Remove it.
Link: https://lkml.kernel.org/r/20220726142918.51693-3-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "A few cleanup and fixup patches for hugetlbfs", v2.
This series contains a few cleaup patches to remove unneeded forward
declaration, use helper macro and so on. More details can be found in the
respective changelogs.
This patch (of 5):
Use helper macro SZ_1K and SZ_1M to do the size conversion. Minor
readability improvement.
Link: https://lkml.kernel.org/r/20220726142918.51693-1-linmiaohe@huawei.com
Link: https://lkml.kernel.org/r/20220726142918.51693-2-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Failure notification is not supported on partitions. So, when we mount a
reflink enabled xfs on a partition with dax option, let it fail with
-EINVAL code.
Link: https://lkml.kernel.org/r/20220609143435.393724-1-ruansy.fnst@fujitsu.com
Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The basic interaction for setting up a userfaultfd is, userspace issues
a UFFDIO_API ioctl, and passes in a set of zero or more feature flags,
indicating the features they would prefer to use.
Of course, different kernels may support different sets of features
(depending on kernel version, kconfig options, architecture, etc).
Userspace's expectations may also not match: perhaps it was built
against newer kernel headers, which defined some features the kernel
it's running on doesn't support.
Currently, if userspace passes in a flag we don't recognize, the
initialization fails and we return -EINVAL. This isn't great, though.
Userspace doesn't have an obvious way to react to this; sure, one of the
features I asked for was unavailable, but which one? The only option it
has is to turn off things "at random" and hope something works.
Instead, modify UFFDIO_API to just ignore any unrecognized feature
flags. The interaction is now that the initialization will succeed, and
as always we return the *subset* of feature flags that can actually be
used back to userspace.
Now userspace has an obvious way to react: it checks if any flags it
asked for are missing. If so, it can conclude this kernel doesn't
support those, and it can either resign itself to not using them, or
fail with an error on its own, or whatever else.
Link: https://lkml.kernel.org/r/20220722201513.1624158-1-axelrasmussen@google.com
Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The use of kmap_atomic() is being deprecated in favor of kmap_local_page().
With kmap_local_page(), the mappings are per thread, CPU local and not
globally visible. Furthermore, the mappings can be acquired from any
context (including interrupts).
Therefore, replace kmap_atomic() with kmap_local_page() in
copy_string_kernel(). Instead of open-coding local mapping + memcpy(),
use memcpy_to_page(). Delete a redundant call to flush_dcache_page().
Tested with xfstests on a QEMU/ KVM x86_32 VM, 6GB RAM, booting a kernel
with HIGHMEM64GB enabled.
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220724212523.13317-1-fmdefrancesco@gmail.com
issues or are too minor to warrant backporting
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCYuCV7gAKCRDdBJ7gKXxA
jrK2AQDeoayQKXJFTcEltKAUTooXM/BoRf+O3ti/xrSWpwta8wEAjaBIJ8e7UlCj
g+p6u/pd38f226ldzI5w3bIBSPCbnwU=
=3rO0
-----END PGP SIGNATURE-----
Merge tag 'mm-hotfixes-stable-2022-07-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton:
"Thirteen hotfixes.
Eight are cc:stable and the remainder are for post-5.18 issues or are
too minor to warrant backporting"
* tag 'mm-hotfixes-stable-2022-07-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mailmap: update Gao Xiang's email addresses
userfaultfd: provide properly masked address for huge-pages
Revert "ocfs2: mount shared volume without ha stack"
hugetlb: fix memoryleak in hugetlb_mcopy_atomic_pte
fs: sendfile handles O_NONBLOCK of out_fd
ntfs: fix use-after-free in ntfs_ucsncmp()
secretmem: fix unhandled fault in truncate
mm/hugetlb: separate path for hwpoison entry in copy_hugetlb_page_range()
mm: fix missing wake-up event for FSDAX pages
mm: fix page leak with multiple threads mapping the same page
mailmap: update Seth Forshee's email address
tmpfs: fix the issue that the mount and remount results are inconsistent.
mm: kfence: apply kmemleak_ignore_phys on early allocated pool
Commit 824ddc601a ("userfaultfd: provide unmasked address on
page-fault") was introduced to fix an old bug, in which the offset in the
address of a page-fault was masked. Concerns were raised - although were
never backed by actual code - that some userspace code might break because
the bug has been around for quite a while. To address these concerns a
new flag was introduced, and only when this flag is set by the user,
userfaultfd provides the exact address of the page-fault.
The commit however had a bug, and if the flag is unset, the offset was
always masked based on a base-page granularity. Yet, for huge-pages, the
behavior prior to the commit was that the address is masked to the
huge-page granulrity.
While there are no reports on real breakage, fix this issue. If the flag
is unset, use the address with the masking that was done before.
Link: https://lkml.kernel.org/r/20220711165906.2682-1-namit@vmware.com
Fixes: 824ddc601a ("userfaultfd: provide unmasked address on page-fault")
Signed-off-by: Nadav Amit <namit@vmware.com>
Reported-by: James Houghton <jthoughton@google.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: James Houghton <jthoughton@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add checks verifying number of inodes stored in the superblock matches
the number computed from number of inodes per group. Also verify we have
at least one block worth of inodes per group. This prevents crashes on
corrupted filesystems.
Reported-by: syzbot+d273f7d7f58afd93be48@syzkaller.appspotmail.com
Signed-off-by: Jan Kara <jack@suse.cz>
Since commit 27b3a5c51b ("kill-the-bkl/reiserfs: drop the fs race
watchdog from _get_block_create_0()"), which removed a label that may
have the pointer 'p' touched in its control flow, related if statements
now eval to constant value now. Just remove them.
Assigning value NULL to p here
293 char *p = NULL;
In the following conditional expression, the value of p is always NULL,
As a result, the kunmap() cannot be executed.
308 if (p)
309 kunmap(bh_result->b_page);
355 if (p)
356 kunmap(bh_result->b_page);
366 if (p)
367 kunmap(bh_result->b_page);
Also, the kmap() cannot be executed.
399 if (!p)
400 p = (char *)kmap(bh_result->b_page);
[JK: Removed unnecessary initialization of 'p' to NULL]
Signed-off-by: Zeng Jingxiang <linuszeng@tencent.com>
Signed-off-by: Kairui Song <kasong@tencent.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20220720083029.1065578-1-zengjx95@gmail.com
This flag was used to communicate that the low-level compression code
already did verify the checksum to the high-level I/O completion code.
But it has been unused for a long time as the upper btrfs_bio for the
decompressed data had a NULL csum pointer basically since that pointer
existed and the code already checks for that a little later.
Note that this does not affect the other use of the checked flag, which
is only used for the COW fixup worker.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently the checksum of compressed extents is verified based on the
compressed data and the lower btrfs_bio, but the actual repair process
is driven by end_bio_extent_readpage on the upper btrfs_bio for the
decompressed data.
This has a bunch of issues, including not being able to properly
communicate the failed mirror up in case that the I/O submission got
preempted, a general loss of if an error was an I/O error or a checksum
verification failure, but most importantly that this design causes
btrfs_clean_io_failure to eventually write back the uncompressed good
data onto the disk sectors that are supposed to contain compressed data.
Fix this by moving the repair to the lower btrfs_bio. To do so, a fair
amount of code has to be reshuffled:
a) the lower btrfs_bio now needs a valid csum pointer. The easiest way
to achieve that is to pass NULL btrfs_lookup_bio_sums and just use
the btrfs_bio management of csums. For a compressed_bio that is
split into multiple btrfs_bios this means additional memory
allocations, but the code becomes a lot more regular.
b) checksum verification now runs directly on the lower btrfs_bio instead
of the compressed_bio. This actually nicely simplifies the end I/O
processing.
c) btrfs_repair_one_sector can't just look up the logical address for
the file offset any more, as there is no corresponding relative
offsets that apply to the file offset and the logic address for
compressed extents. Instead require that the saved bvec_iter in the
btrfs_bio is filled out for all read bios and use that, which again
removes a fair amount of code.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Derive the value of start from the btrfs_bio now that ->file_offset is
always valid. Also export and rename the function so it's available
outside of inode.c as we'll need that soon.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pass the btrfs_bio instead of the plain bio to btrfs_repair_one_sector,
and remove the start and failed_mirror arguments in favor of deriving
them from the btrfs_bio. For this to work ensure that the file_offset
field is also initialized for buffered I/O.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead of counting the sectors just count the bios, with an extra
reference held during submission. This significantly simplifies the
submission side error handling.
This slightly changes completion and error handling of
btrfs_submit_compressed_{read,write} because with the old code the
compressed_bio could have been completed in
submit_compressed_{read,write} only if there was an error during
submission for one of the lower bio, whilst with the new code there is a
chance for this to happen even for successful submission if the all the
lower bios complete before the end of the function is reached.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
When there is more than a single level of redundancy there can also be
multiple bad mirrors, and the current read repair code only repairs the
last bad one.
Restructure btrfs_repair_one_sector so that it records the originally
failed mirror and the number of copies, and then repair all known bad
copies until we reach the originally failed copy in clean_io_failure.
Note that this also means the read repair reads will always start from
the next bad mirror and not mirror 0.
This fixes btrfs/265 in xfstests.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Fold it into the only caller.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When logging a new name, in case of a rename, we pin the log before
changing it. We then either delete a directory entry from the log or
insert a key range item to mark the old name for deletion on log replay.
However when doing one of those log changes we may have another task that
started writing out the log (at btrfs_sync_log()) and it started before
we pinned the log root. So we may end up changing a log tree while its
writeback is being started by another task syncing the log. This can lead
to inconsistencies in a log tree and other unexpected results during log
replay, because we can get some committed node pointing to a node/leaf
that ends up not getting written to disk before the next log commit.
The problem, conceptually, started to happen in commit 88d2beec7e
("btrfs: avoid logging all directory changes during renames"), because
there we started to update the log without joining its current transaction
first.
However the problem only became visible with commit 259c4b96d7
("btrfs: stop doing unnecessary log updates during a rename"), and that is
because we used to pin the log at btrfs_rename() and then before entering
btrfs_log_new_name(), when unlinking the old dentry, we ended up at
btrfs_del_inode_ref_in_log() and btrfs_del_dir_entries_in_log(). Both
of them join the current log transaction, effectively waiting for any log
transaction writeout (due to acquiring the root's log_mutex). This made it
safe even after leaving the current log transaction, because we remained
with the log pinned when we called btrfs_log_new_name().
Then in commit 259c4b96d7 ("btrfs: stop doing unnecessary log updates
during a rename"), we removed the log pinning from btrfs_rename() and
stopped calling btrfs_del_inode_ref_in_log() and
btrfs_del_dir_entries_in_log() during the rename, and started to do all
the needed work at btrfs_log_new_name(), but without joining the current
log transaction, only pinning the log, which is racy because another task
may have started writeout of the log tree right before we pinned the log.
Both commits landed in kernel 5.18, so it doesn't make any practical
difference which should be blamed, but I'm blaming the second commit only
because with the first one, by chance, the problem did not happen due to
the fact we joined the log transaction after pinning the log and unpinned
it only after calling btrfs_log_new_name().
So make btrfs_log_new_name() join the current log transaction instead of
pinning it, so that we never do log updates if it's writeout is starting.
Fixes: 259c4b96d7 ("btrfs: stop doing unnecessary log updates during a rename")
CC: stable@vger.kernel.org # 5.18+
Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Tested-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In btrfs_lookup_dentry releasing the reference of the sub_root and the
running orphan cleanup should only happen if the dentry found actually
represents a subvolume. This can only be true in the 'else' branch as
otherwise either fixup_tree_root_location returned an ENOENT error, in
which case sub_root wouldn't have been changed or if we got a different
errno this means btrfs_get_fs_root couldn't have executed successfully
again meaning sub_root will equal to root. So simplify all the branches
by moving the code into the 'else'.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
After the patch "btrfs: send: fix sending link commands for existing file
paths", we now have two infrastructures to detect and eliminate duplicated
inode references (due to names that got removed and re-added between the
send and parent snapshots):
1) One that works on a single inode ref/extref item;
2) A new one that works acrosss all ref/extref items for an inode, and
it's also more efficient because even in the single ref/extref item
case, it does not do a linear search for all the names encoded in the
ref/extref item, it uses red black trees to speedup up the search.
There's no good reason to keep both infrastructures, we can use the new
one everywhere, and it's always more efficient.
So remove the old infrastructure and change all sites that are using it
to use the new one.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There is a bug sending link commands for existing file paths. When we're
processing an inode, we go over all references. All the new file paths are
added to the "new_refs" list. And all the deleted file paths are added to
the "deleted_refs" list. In the end, when we finish processing the inode,
we iterate over all the items in the "new_refs" list and send link commands
for those file paths. After that, we go over all the items in the
"deleted_refs" list and send unlink commands for them. If there are
duplicated file paths in both lists, we will try to create them before we
remove them. Then the receiver gets an -EEXIST error when trying the link
operations.
Example for having duplicated file paths in both list:
$ btrfs subvolume create vol
# create a file and 2000 hard links to the same inode
$ touch vol/foo
$ for i in {1..2000}; do link vol/foo vol/$i ; done
# take a snapshot for a parent snapshot
$ btrfs subvolume snapshot -r vol snap1
# remove 2000 hard links and re-create the last 1000 links
$ for i in {1..2000}; do rm vol/$i; done;
$ for i in {1001..2000}; do link vol/foo vol/$i; done
# take another one for a send snapshot
$ btrfs subvolume snapshot -r vol snap2
$ mkdir receive_dir
$ btrfs send snap2 -p snap1 | btrfs receive receive_dir/
At subvol snap2
link 1238 -> foo
ERROR: link 1238 -> foo failed: File exists
In this case, we will have the same file paths added to both lists. In the
parent snapshot, reference paths {1..1237} are stored in inode references,
but reference paths {1238..2000} are stored in inode extended references.
In the send snapshot, all reference paths {1001..2000} are stored in inode
references. During the incremental send, we process their inode references
first. In record_changed_ref(), we iterate all its inode references in the
send/parent snapshot. For every inode reference, we also use find_iref() to
check whether the same file path also appears in the parent/send snapshot
or not. Inode references {1238..2000} which appear in the send snapshot but
not in the parent snapshot are added to the "new_refs" list. On the other
hand, Inode references {1..1000} which appear in the parent snapshot but
not in the send snapshot are added to the "deleted_refs" list. Next, when
we process their inode extended references, reference paths {1238..2000}
are added to the "deleted_refs" list because all of them only appear in the
parent snapshot. Now two lists contain items as below:
"new_refs" list: {1238..2000}
"deleted_refs" list: {1..1000}, {1238..2000}
Reference paths {1238..2000} appear in both lists. And as the processing
order mentioned about before, the receiver gets an -EEXIST error when trying
the link operations.
To fix the bug, the idea is to process the "deleted_refs" list before
the "new_refs" list. However, it's not easy to reshuffle the processing
order. For one reason, if we do so, we may unlink all the existing paths
first, there's no valid path anymore for links. And it's inefficient
because we do a bunch of unlinks followed by links for the same paths.
Moreover, it makes less sense to have duplications in both lists. A
reference path cannot not only be regarded as new but also has been seen in
the past, or we won't call it a new path. However, it's also not a good
idea to make find_iref() check a reference against all inode references
and all inode extended references because it may result in large disk
reads.
So we introduce two rbtrees to make the references easier for lookups.
And we also introduce record_new_ref_if_needed() and
record_deleted_ref_if_needed() for changed_ref() to check and remove
duplicated references early.
Reviewed-by: Robbie Ko <robbieko@synology.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: BingJing Chang <bingjingc@synology.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Introduce wrappers to allocate and free recorded_ref structures.
Reviewed-by: Robbie Ko <robbieko@synology.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: BingJing Chang <bingjingc@synology.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When the allocated position doesn't progress, we cannot submit IOs to
finish a block group, but there should be ongoing IOs that will finish a
block group. So, in that case, we wait for a zone to be finished and retry
the allocation after that.
Introduce a new flag BTRFS_FS_NEED_ZONE_FINISH for fs_info->flags to
indicate we need a zone finish to have proceeded. The flag is set when the
allocator detected it cannot activate a new block group. And, it is cleared
once a zone is finished.
CC: stable@vger.kernel.org # 5.16+
Fixes: afba2bc036 ("btrfs: zoned: implement active zone tracking")
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
cow_file_range() works in an all-or-nothing way: if it fails to allocate an
extent for a part of the given region, it gives up all the region including
the successfully allocated parts. On cow_file_range(), run_delalloc_zoned()
writes data for the region only when it successfully allocate all the
region.
This all-or-nothing allocation and write-out are problematic when available
space in all the block groups are get tight with the active zone
restriction. btrfs_reserve_extent() try hard to utilize the left space in
the active block groups and gives up finally and fails with
-ENOSPC. However, if we send IOs for the successfully allocated region, we
can finish a zone and can continue on the rest of the allocation on a newly
allocated block group.
This patch implements the partial write-out for run_delalloc_zoned(). With
this patch applied, cow_file_range() returns -EAGAIN to tell the caller to
do something to progress the further allocation, and tells the successfully
allocated region with done_offset. Furthermore, the zoned extent allocator
returns -EAGAIN to tell cow_file_range() going back to the caller side.
Actually, we still need to wait for an IO to complete to continue the
allocation. The next patch implements that part.
CC: stable@vger.kernel.org # 5.16+
Fixes: afba2bc036 ("btrfs: zoned: implement active zone tracking")
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are two places where allocating a chunk is not enough. These two
places are trying to ensure the space by allocating a chunk. To meet the
condition for active_total_bytes, we also need to activate a block group
there.
CC: stable@vger.kernel.org # 5.16+
Fixes: afba2bc036 ("btrfs: zoned: implement active zone tracking")
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
For metadata space on zoned filesystem, reaching ALLOC_CHUNK{,_FORCE}
means we don't have enough space left in the active_total_bytes. Before
allocating a new chunk, we can try to activate an existing block group
in this case.
Also, allocating a chunk is not enough to grant a ticket for metadata
space on zoned filesystem we need to activate the block group to
increase the active_total_bytes.
btrfs_zoned_activate_one_bg() implements the activation feature. It will
activate a block group by (maybe) finishing a block group. It will give up
activating a block group if it cannot finish any block group.
CC: stable@vger.kernel.org # 5.16+
Fixes: afba2bc036 ("btrfs: zoned: implement active zone tracking")
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The metadata overcommit makes the space reservation flexible but it is also
harmful to active zone tracking. Since we cannot finish a block group from
the metadata allocation context, we might not activate a new block group
and might not be able to actually write out the overcommit reservations.
So, disable metadata overcommit for zoned filesystems. We will ensure
the reservations are under active_total_bytes in the following patches.
CC: stable@vger.kernel.org # 5.16+
Fixes: afba2bc036 ("btrfs: zoned: implement active zone tracking")
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The active_total_bytes, like the total_bytes, accounts for the total bytes
of active block groups in the space_info.
With an introduction of active_total_bytes, we can check if the reserved
bytes can be written to the block groups without activating a new block
group. The check is necessary for metadata allocation on zoned
filesystem. We cannot finish a block group, which may require waiting
for the current transaction, from the metadata allocation context.
Instead, we need to ensure the ongoing allocation (reserved bytes) fits
in active block groups.
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When we run out of active zones and no sufficient space is left in any
block groups, we need to finish one block group to make room to activate a
new block group.
However, we cannot do this for metadata block groups because we can cause a
deadlock by waiting for a running transaction commit. So, do that only for
a data block group.
Furthermore, the block group to be finished has two requirements. First,
the block group must not have reserved bytes left. Having reserved bytes
means we have an allocated region but did not yet send bios for it. If that
region is allocated by the thread calling btrfs_zone_finish(), it results
in a deadlock.
Second, the block group to be finished must not be a SYSTEM block
group. Finishing a SYSTEM block group easily breaks further chunk
allocation by nullifying the SYSTEM free space.
In a certain case, we cannot find any zone finish candidate or
btrfs_zone_finish() may fail. In that case, we fall back to split the
allocation bytes and fill the last spaces left in the block groups.
CC: stable@vger.kernel.org # 5.16+
Fixes: afba2bc036 ("btrfs: zoned: implement active zone tracking")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
For the later patch, convert the return type from bool to int and return
errors. No functional changes.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Use fs_info->max_extent_size also in get_extent_max_capacity() for the
completeness. This is only used for defrag and not really necessary to fix
the metadata reservation size. But, it still suppresses unnecessary defrag
operations.
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
If count_max_extents() uses BTRFS_MAX_EXTENT_SIZE to calculate the number
of extents needed, btrfs release the metadata reservation too much on its
way to write out the data.
Now that BTRFS_MAX_EXTENT_SIZE is replaced with fs_info->max_extent_size,
convert count_max_extents() to use it instead, and fix the calculation of
the metadata reservation.
CC: stable@vger.kernel.org # 5.12+
Fixes: d8e3fb106f ("btrfs: zoned: use ZONE_APPEND write for zoned mode")
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
On zoned filesystem, data write out is limited by max_zone_append_size,
and a large ordered extent is split according the size of a bio. OTOH,
the number of extents to be written is calculated using
BTRFS_MAX_EXTENT_SIZE, and that estimated number is used to reserve the
metadata bytes to update and/or create the metadata items.
The metadata reservation is done at e.g, btrfs_buffered_write() and then
released according to the estimation changes. Thus, if the number of extent
increases massively, the reserved metadata can run out.
The increase of the number of extents easily occurs on zoned filesystem
if BTRFS_MAX_EXTENT_SIZE > max_zone_append_size. And, it causes the
following warning on a small RAM environment with disabling metadata
over-commit (in the following patch).
[75721.498492] ------------[ cut here ]------------
[75721.505624] BTRFS: block rsv 1 returned -28
[75721.512230] WARNING: CPU: 24 PID: 2327559 at fs/btrfs/block-rsv.c:537 btrfs_use_block_rsv+0x560/0x760 [btrfs]
[75721.581854] CPU: 24 PID: 2327559 Comm: kworker/u64:10 Kdump: loaded Tainted: G W 5.18.0-rc2-BTRFS-ZNS+ #109
[75721.597200] Hardware name: Supermicro Super Server/H12SSL-NT, BIOS 2.0 02/22/2021
[75721.607310] Workqueue: btrfs-endio-write btrfs_work_helper [btrfs]
[75721.616209] RIP: 0010:btrfs_use_block_rsv+0x560/0x760 [btrfs]
[75721.646649] RSP: 0018:ffffc9000fbdf3e0 EFLAGS: 00010286
[75721.654126] RAX: 0000000000000000 RBX: 0000000000004000 RCX: 0000000000000000
[75721.663524] RDX: 0000000000000004 RSI: 0000000000000008 RDI: fffff52001f7be6e
[75721.672921] RBP: ffffc9000fbdf420 R08: 0000000000000001 R09: ffff889f8d1fc6c7
[75721.682493] R10: ffffed13f1a3f8d8 R11: 0000000000000001 R12: ffff88980a3c0e28
[75721.692284] R13: ffff889b66590000 R14: ffff88980a3c0e40 R15: ffff88980a3c0e8a
[75721.701878] FS: 0000000000000000(0000) GS:ffff889f8d000000(0000) knlGS:0000000000000000
[75721.712601] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[75721.720726] CR2: 000055d12e05c018 CR3: 0000800193594000 CR4: 0000000000350ee0
[75721.730499] Call Trace:
[75721.735166] <TASK>
[75721.739886] btrfs_alloc_tree_block+0x1e1/0x1100 [btrfs]
[75721.747545] ? btrfs_alloc_logged_file_extent+0x550/0x550 [btrfs]
[75721.756145] ? btrfs_get_32+0xea/0x2d0 [btrfs]
[75721.762852] ? btrfs_get_32+0xea/0x2d0 [btrfs]
[75721.769520] ? push_leaf_left+0x420/0x620 [btrfs]
[75721.776431] ? memcpy+0x4e/0x60
[75721.781931] split_leaf+0x433/0x12d0 [btrfs]
[75721.788392] ? btrfs_get_token_32+0x580/0x580 [btrfs]
[75721.795636] ? push_for_double_split.isra.0+0x420/0x420 [btrfs]
[75721.803759] ? leaf_space_used+0x15d/0x1a0 [btrfs]
[75721.811156] btrfs_search_slot+0x1bc3/0x2790 [btrfs]
[75721.818300] ? lock_downgrade+0x7c0/0x7c0
[75721.824411] ? free_extent_buffer.part.0+0x107/0x200 [btrfs]
[75721.832456] ? split_leaf+0x12d0/0x12d0 [btrfs]
[75721.839149] ? free_extent_buffer.part.0+0x14f/0x200 [btrfs]
[75721.846945] ? free_extent_buffer+0x13/0x20 [btrfs]
[75721.853960] ? btrfs_release_path+0x4b/0x190 [btrfs]
[75721.861429] btrfs_csum_file_blocks+0x85c/0x1500 [btrfs]
[75721.869313] ? rcu_read_lock_sched_held+0x16/0x80
[75721.876085] ? lock_release+0x552/0xf80
[75721.881957] ? btrfs_del_csums+0x8c0/0x8c0 [btrfs]
[75721.888886] ? __kasan_check_write+0x14/0x20
[75721.895152] ? do_raw_read_unlock+0x44/0x80
[75721.901323] ? _raw_write_lock_irq+0x60/0x80
[75721.907983] ? btrfs_global_root+0xb9/0xe0 [btrfs]
[75721.915166] ? btrfs_csum_root+0x12b/0x180 [btrfs]
[75721.921918] ? btrfs_get_global_root+0x820/0x820 [btrfs]
[75721.929166] ? _raw_write_unlock+0x23/0x40
[75721.935116] ? unpin_extent_cache+0x1e3/0x390 [btrfs]
[75721.942041] btrfs_finish_ordered_io.isra.0+0xa0c/0x1dc0 [btrfs]
[75721.949906] ? try_to_wake_up+0x30/0x14a0
[75721.955700] ? btrfs_unlink_subvol+0xda0/0xda0 [btrfs]
[75721.962661] ? rcu_read_lock_sched_held+0x16/0x80
[75721.969111] ? lock_acquire+0x41b/0x4c0
[75721.974982] finish_ordered_fn+0x15/0x20 [btrfs]
[75721.981639] btrfs_work_helper+0x1af/0xa80 [btrfs]
[75721.988184] ? _raw_spin_unlock_irq+0x28/0x50
[75721.994643] process_one_work+0x815/0x1460
[75722.000444] ? pwq_dec_nr_in_flight+0x250/0x250
[75722.006643] ? do_raw_spin_trylock+0xbb/0x190
[75722.013086] worker_thread+0x59a/0xeb0
[75722.018511] kthread+0x2ac/0x360
[75722.023428] ? process_one_work+0x1460/0x1460
[75722.029431] ? kthread_complete_and_exit+0x30/0x30
[75722.036044] ret_from_fork+0x22/0x30
[75722.041255] </TASK>
[75722.045047] irq event stamp: 0
[75722.049703] hardirqs last enabled at (0): [<0000000000000000>] 0x0
[75722.057610] hardirqs last disabled at (0): [<ffffffff8118a94a>] copy_process+0x1c1a/0x66b0
[75722.067533] softirqs last enabled at (0): [<ffffffff8118a989>] copy_process+0x1c59/0x66b0
[75722.077423] softirqs last disabled at (0): [<0000000000000000>] 0x0
[75722.085335] ---[ end trace 0000000000000000 ]---
To fix the estimation, we need to introduce fs_info->max_extent_size to
replace BTRFS_MAX_EXTENT_SIZE, which allow setting the different size for
regular vs zoned filesystem.
Set fs_info->max_extent_size to BTRFS_MAX_EXTENT_SIZE by default. On zoned
filesystem, it is set to fs_info->max_zone_append_size.
CC: stable@vger.kernel.org # 5.12+
Fixes: d8e3fb106f ("btrfs: zoned: use ZONE_APPEND write for zoned mode")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This patch is basically a revert of commit 5a80d1c6a2 ("btrfs: zoned:
remove max_zone_append_size logic"), but without unnecessary ASSERT and
check. The max_zone_append_size will be used as a hint to estimate the
number of extents to cover delalloc/writeback region in the later commits.
The size of a ZONE APPEND bio is also limited by queue_max_segments(), so
this commit considers it to calculate max_zone_append_size. Technically, a
bio can be larger than queue_max_segments() * PAGE_SIZE if the pages are
contiguous. But, it is safe to consider "queue_max_segments() * PAGE_SIZE"
as an upper limit of an extent size to calculate the number of extents
needed to write data.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently btrfs_ino() tries to use first the objectid of the inode's
location key. This is to avoid truncation of the inode number on 32 bits
platforms because the i_ino field of struct inode has the unsigned long
type, while the objectid is a 64 bits unsigned type (u64) on every system.
This logic was added in commit 33345d0152 ("Btrfs: Always use 64bit
inode number").
However if we are running on a 64 bits system, we can always directly
return the i_ino value from struct inode, which eliminates the need for
he special if statement that tests for a location key type of
BTRFS_ROOT_ITEM_KEY - in which case i_ino may not have the same value as
the objectid in the inode's location objectid, it may have a value of
BTRFS_EMPTY_SUBVOL_DIR_OBJECTID, for the case of snapshots of trees with
subvolumes/snapshots inside them.
So add a special version for 64 bits system that directly returns i_ino
of struct inode. This eliminates one branch and reduces the overall code
size, since btrfs_ino() is an inline function that is extensively used.
Before:
$ size fs/btrfs/btrfs.ko
text data bss dec hex filename
1617487 189240 29032 1835759 1c02ef fs/btrfs/btrfs.ko
After:
$ size fs/btrfs/btrfs.ko
text data bss dec hex filename
1612028 189180 29032 1830240 1bed60 fs/btrfs/btrfs.ko
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We currently don't use the location key of the btree inode, its content
is set to zeroes, as it's a special inode that is not persisted (it has
no inode item stored in any btree).
At btrfs_ino(), an inline function used extensively in btrfs, we have
this special check if the given inode's location objectid is 0, and if it
is, we return the value stored in the VFS' inode i_ino field instead
(which is BTRFS_BTREE_INODE_OBJECTID for the btree inode).
To reduce the code at btrfs_ino(), we can simply set the objectid of the
btree inode to the value BTRFS_BTREE_INODE_OBJECTID. This eliminates the
need to check for the special case of the objectid being zero, with the
side effect of reducing the overall code size and having less code to
execute, as btrfs_ino() is an inline function.
Before:
$ size fs/btrfs/btrfs.ko
text data bss dec hex filename
1620502 189240 29032 1838774 1c0eb6 fs/btrfs/btrfs.ko
After:
$ size fs/btrfs/btrfs.ko
text data bss dec hex filename
1617487 189240 29032 1835759 1c02ef fs/btrfs/btrfs.ko
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
kmap_atomic() is being deprecated in favor of kmap_local_page() where it
is feasible. With kmap_local_page() mappings are per thread, CPU local,
and not globally visible.
The last use of kmap_atomic is in inode.c where the context is atomic [1]
and can be safely replaced by kmap_local_page.
Tested with xfstests on a QEMU + KVM 32-bits VM with 4GB RAM and booting a
kernel with HIGHMEM64GB enabled.
[1] https://lore.kernel.org/linux-btrfs/20220601132545.GM20633@twin.jikos.cz/
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The use of kmap() is being deprecated in favor of kmap_local_page(). With
kmap_local_page(), the mapping is per thread, CPU local and not globally
visible.
Therefore, use kmap_local_page() / kunmap_local() in zlib_decompress_bio()
because in this function the mappings are per thread and are not visible
in other contexts.
Tested with xfstests on QEMU + KVM 32-bits VM with 4GB of RAM and
HIGHMEM64G enabled. This patch passes 26/26 tests of group "compress".
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The use of kmap() is being deprecated in favor of kmap_local_page(). With
kmap_local_page(), the mapping is per thread, CPU local and not globally
visible.
Therefore, use kmap_local_page() / kunmap_local() in zlib_compress_pages()
because in this function the mappings are per thread and are not visible
in other contexts. Furthermore, drop the mappings of "out_page" which is
allocated within zlib_compress_pages() with alloc_page(GFP_NOFS) and use
page_address().
Tested with xfstests on a QEMU + KVM 32-bits VM with 4GB of RAM booting
a kernel with HIGHMEM64G enabled. This patch passes 26/26 tests of group
"compress".
CC: Qu Wenruo <wqu@suse.com>
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The use of kmap() is being deprecated in favor of kmap_local_page(). With
kmap_local_page(), the mapping is per thread, CPU local and not globally
visible.
Therefore, use kmap_local_page() / kunmap_local() in zstd.c because in this
file the mappings are per thread and are not visible in other contexts. In
the meanwhile use plain page_address() on output pages allocated with
the GFP_NOFS flag instead of calling kmap*() on them (since they are
always allocated from ZONE_NORMAL).
Tested with xfstests on QEMU + KVM 32 bits VM with 4GB of RAM, booting a
kernel with HIGHMEM64G enabled.
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently, for a direct IO write, if we need to fallback to buffered IO,
either to satisfy the whole write operation or just a part of it, we do
it in the current context even if it's a NOWAIT context. This is not ideal
because we currently don't have support for NOWAIT semantics in the
buffered IO path (we can block for several reasons), so we should instead
return -EAGAIN to the caller, so that it knows it should retry (the whole
operation or what's left of it) in a context where blocking is acceptable.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The number of block group reserve types BTRFS_BLOCK_RSV_* is small and
fits to u8 and there's enough left in case we want to add more.
For type safety use the enum but make it 8 bits in the structure to save
space.
The structure size is now 48 on release build, making a slight
improvement in structures where it's embedded, like btrfs_fs_info or
btrfs_inode.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Use simple bool type for the block reserve failfast status, there's
short to save space as there used to be int but there's no reason for
that.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Use simple bool type for the block reserve full status, there's short to
save space as there used to be int but there's no reason for that.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Always consume the bio and call the end_io handler on error instead of
returning an error and letting the caller handle it. This matches what
the block layer submission and the other btrfs bio submission handlers do
and avoids any confusion on who needs to handle errors.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_wq_submit_bio is used for writeback under memory pressure.
Instead of failing the I/O when we can't allocate the async_submit_bio,
just punt back to the synchronous submission path.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_submit_data_write_bio special cases the reloc root because the
checksums are preloaded, but only does so for the !sync case. The sync
case can't happen for data relocation, but just handling it more generally
significantly simplifies the logic.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Transfer the bio counter reference acquired by btrfs_submit_bio to
raid56_parity_write and raid56_parity_recovery together with the bio
that the reference was acquired for instead of acquiring another
reference in those helpers and dropping the original one in
btrfs_submit_bio.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Always consume the bio and call the end_io handler on error instead of
returning an error and letting the caller handle it. This matches what
the block layer submission does and avoids any confusion on who
needs to handle errors.
Also use the proper bool type for the generic_io argument.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Always consume the bio and call the end_io handler on error instead of
returning an error and letting the caller handle it. This matches what
the block layer submission does and avoids any confusion on who
needs to handle errors.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Always consume the bio and call the end_io handler on error instead of
returning an error and letting the caller handle it. This matches
what the block layer submission does and avoids any confusion on who
needs to handle errors.
As this requires touching all the callers, rename the function to
btrfs_submit_bio, which describes the functionality much better.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
For profiles other than RAID56, __btrfs_map_block() returns @map_length
as min(stripe_end, logical + *length), which is also the same result
from btrfs_get_io_geometry().
But for RAID56, __btrfs_map_block() returns @map_length as stripe_len.
This strange behavior is going to hurt incoming bio split at
btrfs_map_bio() time, as we will use @map_length as bio split size.
Fix this behavior by returning @map_length by the same calculation as
for other profiles.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
The raid56 code assumes a fixed stripe length BTRFS_STRIPE_LEN but there
are functions passing it as arguments, this is not necessary. The fixed
value has been used for a long time and though the stripe length should
be configurable by super block member stripesize, this hasn't been
implemented and would require more changes so we don't need to keep this
code around until then.
Partially based on a patch from Qu Wenruo.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
[ update changelog ]
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The inode cache feature was removed in kernel 5.11, and we no longer have
any code that reads from or writes to inode caches. We may still mount a
filesystem that has inode caches, but they are ignored.
Remove the check for an inode cache from btrfs_is_free_space_inode(),
since we no longer have code to trigger reads from an inode cache or
writes to an inode cache. The check at send.c is still needed, because
in case we find a filesystem with an inode cache, we must ignore it.
Also leave the checks at tree-checker.c, as they are sanity checks.
This eliminates a dead branch and reduces the amount of code since it's
in an inline function.
Before:
$ size fs/btrfs/btrfs.ko
text data bss dec hex filename
1620662 189240 29032 1838934 1c0f56 fs/btrfs/btrfs.ko
After:
$ size fs/btrfs/btrfs.ko
text data bss dec hex filename
1620502 189240 29032 1838774 1c0eb6 fs/btrfs/btrfs.ko
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This flag has been merged in 3.10 and is effectively always-on. Its
status depends on the host page size so there's another way to guarantee
compatibility with old kernels.
Due to a bug introduced in 6f93e834fa ("btrfs: fix upper limit for
max_inline for page size 64K") the flag is not persisted among features
in the superblock so it's not reliable.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
This feature has been the default for about 13 year. At this point it's
safe to consider it an indispensable feature of BTRFS as such there's
no need to advertise it in sysfs. Remove the global sysfs feature file,
the per-filesystem feature file has never been there.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Skinny extents have been a default mkfs feature since version 3.18 i
(introduced in btrfs-progs commit 6715de04d9a7 ("btrfs-progs: mkfs:
make skinny-metadata default") ). It really doesn't bring any value to
users to simply remove it.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Added in commit 727011e07c ("Btrfs: allow metadata blocks larger than
the page size") in 2010 and it's been default for mkfs since 3.12
(2013). The message doesn't really convey any useful information to
users. Remove it.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The chained assignments may be convenient to write, but make readability
a bit worse as it's too easy to overlook that there are several values
set on the same line while this is rather an exception. Making it
consistent everywhere avoids surprises.
The pattern where inode times are initialized reuses the first value and
the order is mtime, ctime. In other blocks the assignments are expanded
so the order of variables is similar to the neighboring code.
Signed-off-by: David Sterba <dsterba@suse.com>
Use the same expression for stripe_nr for RAID0 (map->sub_stripes is 1)
and RAID10 (map->sub_stripes is 2), with equivalent results.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There's a sequence of hard coded values for RAID1 profiles that are
already stored in the raid_attr table that should be used instead.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Commit 6f93e834fa seemingly inadvertently moved the code responsible
for flagging the filesystem as having BIG_METADATA to a place where
setting the flag was essentially lost. This means that
filesystems created with kernels containing this bug (starting with 5.15)
can potentially be mounted by older (pre-3.4) kernels. In reality
chances for this happening are low because there are other incompat
flags introduced in the mean time. Still the correct behavior is to set
INCOMPAT_BIG_METADATA flag and persist this in the superblock.
Fixes: 6f93e834fa ("btrfs: fix upper limit for max_inline for page size 64K")
CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Per user request, print the checksum type and implementation at mount
time among the messages. The checksum is user configurable and the
actual crypto implementation is useful to see for performance reasons.
The same information is also available after mount in
/sys/fs/FSID/checksum file.
Example:
[25.323662] BTRFS info (device vdb): using sha256 (sha256-generic) checksum algorithm
Link: https://github.com/kdave/btrfs-progs/issues/483
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
If you try to force a chunk allocation, but you race with another chunk
allocation, you will end up waiting on the chunk allocation that just
occurred and then allocate another chunk. If you have many threads all
doing this at once you can way over-allocate chunks.
Fix this by resetting force to NO_FORCE, that way if we think we need to
allocate we can, otherwise we don't force another chunk allocation if
one is already happening.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
CC: stable@vger.kernel.org # 5.4+
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are file attributes inherited from previous ext2 SETFLAGS/GETFLAGS
and later from XFLAGS interfaces, now commonly found under the
'fileattr' API. This corresponds to the individual inode bits and that's
part of the on-disk format, so this is suitable for the protocol. The
other interfaces contain a lot of cruft or bits that btrfs does not
support yet.
Currently the value is u64 and matches btrfs_inode_item. Not all the
bits can be set by ioctls (like NODATASUM or READONLY), but we can send
them over the protocol and leave it up to the receiving side what and
how to apply.
As some of the flags, eg. IMMUTABLE, can prevent any further changes,
the receiving side needs to understand that and apply the changes in the
right order, or possibly with some intermediate steps. This should be
easier, future proof and simpler on the protocol layer than implementing
in kernel.
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When send v1 was introduced the otime (inode creation time) was not
available, however the attribute in btrfs send protocol exists. Though
it would be possible to add it for v1 too as the attribute would be
ignored by v1 receive, let's not change the layout of v1 and only add
that to v2+. The otime cannot be changed and is only informative.
Signed-off-by: David Sterba <dsterba@suse.com>
When handling a real world transid mismatch image, it's hard to know
which copy is corrupted, as the error messages just look like this:
BTRFS warning (device dm-3): checksum verify failed on 30408704 wanted 0xcdcdcdcd found 0x3c0adc8e level 0
BTRFS warning (device dm-3): checksum verify failed on 30408704 wanted 0xcdcdcdcd found 0x3c0adc8e level 0
BTRFS warning (device dm-3): checksum verify failed on 30408704 wanted 0xcdcdcdcd found 0x3c0adc8e level 0
BTRFS warning (device dm-3): checksum verify failed on 30408704 wanted 0xcdcdcdcd found 0x3c0adc8e level 0
We don't even know if the retry is caused by btrfs or the VFS retry.
To make things a little easier to read, add mirror number for all
related tree block read errors.
So the above messages would look like this:
BTRFS warning (device dm-3): checksum verify failed on logical 30408704 mirror 1 wanted 0xcdcdcdcd found 0x3c0adc8e level 0
BTRFS warning (device dm-3): checksum verify failed on logical 30408704 mirror 2 wanted 0xcdcdcdcd found 0x3c0adc8e level 0
BTRFS warning (device dm-3): checksum verify failed on logical 30408704 mirror 1 wanted 0xcdcdcdcd found 0x3c0adc8e level 0
BTRFS warning (device dm-3): checksum verify failed on logical 30408704 mirror 2 wanted 0xcdcdcdcd found 0x3c0adc8e level 0
Signed-off-by: Qu Wenruo <wqu@suse.com>
[ update messages, add "logical" ]
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The 'goto out' in cow_file_range() in the exit block are not necessary
and jump back. Replace them with return, while still keeping 'goto out'
in the main code.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ keep goto in the main code, update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
When cow_file_range() fails in the middle of the allocation loop, it
unlocks the pages but leaves the ordered extents intact. Thus, we need
to call btrfs_cleanup_ordered_extents() to finish the created ordered
extents.
Also, we need to call end_extent_writepage() if locked_page is available
because btrfs_cleanup_ordered_extents() never processes the region on
the locked_page.
Furthermore, we need to set the mapping as error if locked_page is
unavailable before unlocking the pages, so that the errno is properly
propagated to the user space.
CC: stable@vger.kernel.org # 5.18+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_cleanup_ordered_extents() assumes locked_page to be non-NULL, so it
is not usable for submit_uncompressed_range() which can have NULL
locked_page.
Add support supports locked_page == NULL case. Also, it rewrites
redundant "page_offset(locked_page)".
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There is a hung_task report on zoned btrfs like below.
https://github.com/naota/linux/issues/59
[726.328648] INFO: task rocksdb:high0:11085 blocked for more than 241 seconds.
[726.329839] Not tainted 5.16.0-rc1+ #1
[726.330484] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[726.331603] task:rocksdb:high0 state:D stack: 0 pid:11085 ppid: 11082 flags:0x00000000
[726.331608] Call Trace:
[726.331611] <TASK>
[726.331614] __schedule+0x2e5/0x9d0
[726.331622] schedule+0x58/0xd0
[726.331626] io_schedule+0x3f/0x70
[726.331629] __folio_lock+0x125/0x200
[726.331634] ? find_get_entries+0x1bc/0x240
[726.331638] ? filemap_invalidate_unlock_two+0x40/0x40
[726.331642] truncate_inode_pages_range+0x5b2/0x770
[726.331649] truncate_inode_pages_final+0x44/0x50
[726.331653] btrfs_evict_inode+0x67/0x480
[726.331658] evict+0xd0/0x180
[726.331661] iput+0x13f/0x200
[726.331664] do_unlinkat+0x1c0/0x2b0
[726.331668] __x64_sys_unlink+0x23/0x30
[726.331670] do_syscall_64+0x3b/0xc0
[726.331674] entry_SYSCALL_64_after_hwframe+0x44/0xae
[726.331677] RIP: 0033:0x7fb9490a171b
[726.331681] RSP: 002b:00007fb943ffac68 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
[726.331684] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb9490a171b
[726.331686] RDX: 00007fb943ffb040 RSI: 000055a6bbe6ec20 RDI: 00007fb94400d300
[726.331687] RBP: 00007fb943ffad00 R08: 0000000000000000 R09: 0000000000000000
[726.331688] R10: 0000000000000031 R11: 0000000000000246 R12: 00007fb943ffb000
[726.331690] R13: 00007fb943ffb040 R14: 0000000000000000 R15: 00007fb943ffd260
[726.331693] </TASK>
While we debug the issue, we found running fstests generic/551 on 5GB
non-zoned null_blk device in the emulated zoned mode also had a
similar hung issue.
Also, we can reproduce the same symptom with an error injected
cow_file_range() setup.
The hang occurs when cow_file_range() fails in the middle of
allocation. cow_file_range() called from do_allocation_zoned() can
split the give region ([start, end]) for allocation depending on
current block group usages. When btrfs can allocate bytes for one part
of the split regions but fails for the other region (e.g. because of
-ENOSPC), we return the error leaving the pages in the succeeded regions
locked. Technically, this occurs only when @unlock == 0. Otherwise, we
unlock the pages in an allocated region after creating an ordered
extent.
Considering the callers of cow_file_range(unlock=0) won't write out
the pages, we can unlock the pages on error exit from
cow_file_range(). So, we can ensure all the pages except @locked_page
are unlocked on error case.
In summary, cow_file_range now behaves like this:
- page_started == 1 (return value)
- All the pages are unlocked. IO is started.
- unlock == 1
- All the pages except @locked_page are unlocked in any case
- unlock == 0
- On success, all the pages are locked for writing out them
- On failure, all the pages except @locked_page are unlocked
Fixes: 42c0110009 ("btrfs: zoned: introduce dedicated data write path for zoned filesystems")
CC: stable@vger.kernel.org # 5.12+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Export commit stats in file
/sys/fs/btrfs/UUID/commit_stats
with example output like:
commits 123
last_commit_ms 11
max_commit_ms 150
total_commit_ms 2000
The values are in one file so reading them at a single time will give a
more consistent view. The stats are internally tracked in nanoseconds so
the cumulative values should not suffer from rounding errors.
Writing 0 to the file 'commit_stats' will reset max_commit_ms.
Initial values are set at first mount of the filesystem.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Ioannis Angelakopoulos <iangelak@fb.com>
[ update changelog ]
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Track several stats about transaction commit, to be later exported via
sysfs:
- number of commits so far
- duration of the last commit in ns
- maximum commit duration seen so far in ns
- total duration for all commits so far in ns
The update of the commit stats occurs after the commit thread has gone
through all the logic that checks if there is another thread committing
at the same time. This means that we only account for actual commit work
in the commit stats we report and not the time the thread spends waiting
until it is ready to do the commit work.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Ioannis Angelakopoulos <iangelak@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Same as in commit 21b4ee7029 ("xfs: drop ->writepage completely"): we
can remove the callback as it's only used in one place - single page
writeback from memory reclaim and is not called for cgroup writeback at
all.
We only allow such writeback from kswapd, not from direct memory
reclaim, and so it is rarely used. When it comes from kswapd, it is
effectively random dirty page shoot-down, which is horrible for IO
patterns. We can rely on background writeback to clean all dirty pages
in an efficient way and not let it be interrupted by kswapd.
Suggested-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
The whole send operation is restartable and handling properly a buffer
write may not be easy. We can't know what caused that and if a short
delay and retry will fix it or how many retries should be performed in
case it's a temporary condition.
The error value is returned to the ioctl caller so in case it's
transient problem, the user would be notified about the reason. Remove
the TODO note as there's no plan to handle ERESTARTSYS.
Signed-off-by: David Sterba <dsterba@suse.com>
We don't need this ifdef as the header file is not shared, the protocol
definition used by userspace should be from libbtrfs or libbtrfsutil.
Signed-off-by: David Sterba <dsterba@suse.com>
Btrfs currently limits direct I/O reads to a single sector, which goes
back to commit c329861da4 ("Btrfs: don't allocate a separate csums
array for direct reads") from Josef. That commit changes the direct I/O
code to ".. use the private part of the io_tree for our csums.", but ten
years later that isn't how checksums for direct reads work, instead they
use a csums allocation on a per-btrfs_dio_private basis (which have their
own performance problem for small I/O, but that will be addressed later).
There is no fundamental limit in btrfs itself to limit the I/O size
except for the size of the checksum array that scales linearly with
the number of sectors in an I/O. Pick a somewhat arbitrary limit of
256 limits, which matches what the buffered reads typically see as
the upper limit as the limit for direct I/O as well.
This significantly improves direct read performance. For example a fio
run doing 1 MiB aio reads with a queue depth of 1 roughly triples the
throughput:
Baseline:
READ: bw=65.3MiB/s (68.5MB/s), 65.3MiB/s-65.3MiB/s (68.5MB/s-68.5MB/s), io=19.1GiB (20.6GB), run=300013-300013msec
With this patch:
READ: bw=196MiB/s (206MB/s), 196MiB/s-196MiB/s (206MB/s-206MB/s), io=57.5GiB (61.7GB), run=300006-300006msc
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
There is a small workload which will always fail with recent kernel:
(A simplified version from btrfs/125 test case)
mkfs.btrfs -f -m raid5 -d raid5 -b 1G $dev1 $dev2 $dev3
mount $dev1 $mnt
xfs_io -f -c "pwrite -S 0xee 0 1M" $mnt/file1
sync
umount $mnt
btrfs dev scan -u $dev3
mount -o degraded $dev1 $mnt
xfs_io -f -c "pwrite -S 0xff 0 128M" $mnt/file2
umount $mnt
btrfs dev scan
mount $dev1 $mnt
btrfs balance start --full-balance $mnt
umount $mnt
The failure is always failed to read some tree blocks:
BTRFS info (device dm-4): relocating block group 217710592 flags data|raid5
BTRFS error (device dm-4): parent transid verify failed on 38993920 wanted 9 found 7
BTRFS error (device dm-4): parent transid verify failed on 38993920 wanted 9 found 7
...
[CAUSE]
With the recently added debug output, we can see all RAID56 operations
related to full stripe 38928384:
56.1183: raid56_read_partial: full_stripe=38928384 devid=2 type=DATA1 offset=0 opf=0x0 physical=9502720 len=65536
56.1185: raid56_read_partial: full_stripe=38928384 devid=3 type=DATA2 offset=16384 opf=0x0 physical=9519104 len=16384
56.1185: raid56_read_partial: full_stripe=38928384 devid=3 type=DATA2 offset=49152 opf=0x0 physical=9551872 len=16384
56.1187: raid56_write_stripe: full_stripe=38928384 devid=3 type=DATA2 offset=0 opf=0x1 physical=9502720 len=16384
56.1188: raid56_write_stripe: full_stripe=38928384 devid=3 type=DATA2 offset=32768 opf=0x1 physical=9535488 len=16384
56.1188: raid56_write_stripe: full_stripe=38928384 devid=1 type=PQ1 offset=0 opf=0x1 physical=30474240 len=16384
56.1189: raid56_write_stripe: full_stripe=38928384 devid=1 type=PQ1 offset=32768 opf=0x1 physical=30507008 len=16384
56.1218: raid56_write_stripe: full_stripe=38928384 devid=3 type=DATA2 offset=49152 opf=0x1 physical=9551872 len=16384
56.1219: raid56_write_stripe: full_stripe=38928384 devid=1 type=PQ1 offset=49152 opf=0x1 physical=30523392 len=16384
56.2721: raid56_parity_recover: full stripe=38928384 eb=39010304 mirror=2
56.2723: raid56_parity_recover: full stripe=38928384 eb=39010304 mirror=2
56.2724: raid56_parity_recover: full stripe=38928384 eb=39010304 mirror=2
Before we enter raid56_parity_recover(), we have triggered some metadata
write for the full stripe 38928384, this leads to us to read all the
sectors from disk.
Furthermore, btrfs raid56 write will cache its calculated P/Q sectors to
avoid unnecessary read.
This means, for that full stripe, after any partial write, we will have
stale data, along with P/Q calculated using that stale data.
Thankfully due to patch "btrfs: only write the sectors in the vertical stripe
which has data stripes" we haven't submitted all the corrupted P/Q to disk.
When we really need to recover certain range, aka in
raid56_parity_recover(), we will use the cached rbio, along with its
cached sectors (the full stripe is all cached).
This explains why we have no event raid56_scrub_read_recover()
triggered.
Since we have the cached P/Q which is calculated using the stale data,
the recovered one will just be stale.
In our particular test case, it will always return the same incorrect
metadata, thus causing the same error message "parent transid verify
failed on 39010304 wanted 9 found 7" again and again.
[BTRFS DESTRUCTIVE RMW PROBLEM]
Test case btrfs/125 (and above workload) always has its trouble with
the destructive read-modify-write (RMW) cycle:
0 32K 64K
Data1: | Good | Good |
Data2: | Bad | Bad |
Parity: | Good | Good |
In above case, if we trigger any write into Data1, we will use the bad
data in Data2 to re-generate parity, killing the only chance to recovery
Data2, thus Data2 is lost forever.
This destructive RMW cycle is not specific to btrfs RAID56, but there
are some btrfs specific behaviors making the case even worse:
- Btrfs will cache sectors for unrelated vertical stripes.
In above example, if we're only writing into 0~32K range, btrfs will
still read data range (32K ~ 64K) of Data1, and (64K~128K) of Data2.
This behavior is to cache sectors for later update.
Incidentally commit d4e28d9b5f ("btrfs: raid56: make steal_rbio()
subpage compatible") has a bug which makes RAID56 to never trust the
cached sectors, thus slightly improve the situation for recovery.
Unfortunately, follow up fix "btrfs: update stripe_sectors::uptodate in
steal_rbio" will revert the behavior back to the old one.
- Btrfs raid56 partial write will update all P/Q sectors and cache them
This means, even if data at (64K ~ 96K) of Data2 is free space, and
only (96K ~ 128K) of Data2 is really stale data.
And we write into that (96K ~ 128K), we will update all the parity
sectors for the full stripe.
This unnecessary behavior will completely kill the chance of recovery.
Thankfully, an unrelated optimization "btrfs: only write the sectors
in the vertical stripe which has data stripes" will prevent
submitting the write bio for untouched vertical sectors.
That optimization will keep the on-disk P/Q untouched for a chance for
later recovery.
[FIX]
Although we have no good way to completely fix the destructive RMW
(unless we go full scrub for each partial write), we can still limit the
damage.
With patch "btrfs: only write the sectors in the vertical stripe which
has data stripes" now we won't really submit the P/Q of unrelated
vertical stripes, so the on-disk P/Q should still be fine.
Now we really need to do is just drop all the cached sectors when doing
recovery.
By this, we have a chance to read the original P/Q from disk, and have a
chance to recover the stale data, while still keep the cache to speed up
regular write path.
In fact, just dropping all the cache for recovery path is good enough to
allow the test case btrfs/125 along with the small script to pass
reliably.
The lack of metadata write after the degraded mount, and forced metadata
COW is saving us this time.
So this patch will fix the behavior by not trust any cache in
__raid56_parity_recover(), to solve the problem while still keep the
cache useful.
But please note that this test pass DOES NOT mean we have solved the
destructive RMW problem, we just do better damage control a little
better.
Related patches:
- btrfs: only write the sectors in the vertical stripe
- d4e28d9b5f ("btrfs: raid56: make steal_rbio() subpage compatible")
- btrfs: update stripe_sectors::uptodate in steal_rbio
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
finish_func is always set to finish_ordered_fn, so remove it and also
the now pointless and somewhat confusingly named
__endio_write_update_ordered wrapper.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
With Filipe's recent rework of the delayed inode code one aspect which
isn't batched is the release of the reserved metadata of delayed inode's
delete items. With this patch on top of Filipe's rework and running the
same test as provided in the description of a patch titled
"btrfs: improve batch deletion of delayed dir index items" I observe
the following change of the number of calls to btrfs_block_rsv_release:
Before this change:
- block_rsv_release: 1004
- btrfs_delete_delayed_items_total_time: 14602
- delete_batches: 505
After:
- block_rsv_release: 510
- btrfs_delete_delayed_items_total_time: 13643
- delete_batches: 507
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Btrfs on-disk format has reserved the first 1MiB for the primary super
block (at 64KiB offset) and bootloaders may also use this space.
This behavior is only introduced since v4.1 btrfs-progs release,
although kernel can ensure we never touch the reserved range of super
blocks, it's better to inform the end users, and a balance will resolve
the problem.
Signed-off-by: Qu Wenruo <wqu@suse.com>
[ update changelog and message ]
Signed-off-by: David Sterba <dsterba@suse.com>
There's a reserved space on each device of size 1MiB that can be used by
bootloaders or to avoid accidental overwrite. Use a symbolic constant
with the explaining comment instead of hard coding the value and
multiple comments.
Note: since btrfs-progs v4.1, mkfs.btrfs will reserve the first 1MiB for
the primary super block (at offset 64KiB), until then the range could
have been used by mistake. Kernel has been always respecting the 1MiB
range for writes.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
There's only one function we pass to iterate_inodes_from_logical as
iterator, so we can drop the indirection and call it directly, after
moving the function to backref.c
Signed-off-by: David Sterba <dsterba@suse.com>
The inode reference iterator interface takes parameters that are derived
from the context parameter, but as it's a void* type the values are
passed individually.
Change the ctx type to inode_fs_path as it's the only thing we pass and
drop any parameters that are derived from that.
Signed-off-by: David Sterba <dsterba@suse.com>
The functions for iterating inode reference take a function parameter
but there's only one value, inode_to_path(). Remove the indirection and
call the function. As paths_from_inode would become just an alias for
iterate_irefs(), merge the two into one function.
Signed-off-by: David Sterba <dsterba@suse.com>
For all non-RAID56 profiles, we can use btrfs_raid_array[].ncopies
directly, only for RAID5 and RAID6 we need some extra handling as
there's no table value for that.
For RAID10 there's a change from sub_stripes to ncopies. The values are
the same but semantically we want to use number of copies, as this is
what btrfs_num_copies does.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Use the raid table instead of hard coded values and rename the helper as
it is exported. This could make later extension on RAID56 based
profiles easier.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In __btrfs_map_block() we have an assignment to @max_errors using
nr_parity_stripes().
Although it works for RAID56 it's confusing. Replace it with
btrfs_chunk_max_errors().
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
For scrub_stripe() we can easily calculate the dev extent length as we
have the full info of the chunk.
Thus there is no need to pass @dev_extent_len from the caller, and we
introduce a helper, btrfs_calc_stripe_length(), to do the calculation
from extent_map structure.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Simplify helper to return only next and prev pointers, we don't need all
the node/parent/prev/next pointers of __etree_search as there are now
other specialized helpers. Rename parameters so they follow the naming.
Signed-off-by: David Sterba <dsterba@suse.com>
With a slight extension of tree_search_for_insert (fill the return node
and parent return parameters) we can avoid calling __etree_search from
tree_search, that could be removed eventually in followup patches.
Signed-off-by: David Sterba <dsterba@suse.com>
The call chain from
tree_search
tree_search_for_insert
__etree_search
can be open coded and allow further simplifications, here we need a tree
search with fallback to the next node in case it's not found. This is
represented as __etree_search parameters next_ret=valid, prev_ret=NULL.
Signed-off-by: David Sterba <dsterba@suse.com>
In two cases the exact location where to insert the extent state is
known at the call time so we don't need to pass it to insert_state that
takes the fast path.
Signed-off-by: David Sterba <dsterba@suse.com>
The bits are passed to all extent state helpers for no apparent reason,
the value only read and never updated so remove the indirection and pass
it directly. Also unify the type to u32 where needed.
Signed-off-by: David Sterba <dsterba@suse.com>
Let callers of insert_state to set up the extent state to allow further
simplifications of the parameters.
Signed-off-by: David Sterba <dsterba@suse.com>
The rbtree search is a known pattern and can be open coded, allowing to
remove the tree_insert and further cleanups.
Signed-off-by: David Sterba <dsterba@suse.com>
Preparatory work to remove tree_insert from extent_io.c, the rbtree
search loop is a known and simple so it can be open coded.
Signed-off-by: David Sterba <dsterba@suse.com>
Originally it's iterating all the sectors which has dbitmap sector for
the vertical stripe.
It can be easily converted to sector bytenr iteration with an test_bit()
call.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This function doesn't even utilize full stripe skip, just iterate all
the data sectors is definitely enough.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The double loop is just checking if the page for the vertical stripe
is allocated.
We can easily convert it to single loop and get rid of @stripe variable.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The double for loop can be easily converted to single for loop as we're
really iterating the sectors in their bytenr order.
The only exception is the full stripe skip, however that can also easily
be done inside the loop. Add an ASSERT() along with a comment for that
specific case.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We can easily calculate the stripe number and sector number inside the
stripe. Thus there is not much need for a double for loop.
For the only case we want to skip the whole stripe, we can manually
increase @total_sector_nr.
This is not a recommended behavior, thus every time the iterator gets
modified there will be a comment along with an ASSERT() for it.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently we will return 1 or -EAGAIN if we decide we need to commit
the transaction rather than sync the log. In practice this doesn't
really matter, we interpret any !0 and !BTRFS_NO_LOG_SYNC as needing to
commit the transaction. However this makes it hard to figure out what
the correct thing to do is.
Fix this up by defining BTRFS_LOG_FORCE_COMMIT and using this in all the
places where we want to force the transaction to be committed.
CC: stable@vger.kernel.org # 5.15+
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>
When debugging a reference counting issue with ordered extents, I've found
we're lacking a lot of tracepoint coverage in the ordered extent code.
Close these gaps by adding tracepoints after every refcount_inc() in the
ordered extent code.
Reviewed-by: Boris Burkov <boris@bur.io>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We've hidden the zoned support in sysfs under debug config for the first
releases but now the stability is reasonable, though not all features
have been implemented.
Signed-off-by: David Sterba <dsterba@suse.com>
Mapping block for discard doesn't really share any code with the regular
block mapping case. Split it out into an entirely separate helper
that just returns an array of btrfs_discard_stripe structures and the
number of stripes.
This removes the need for the length field in the btrfs_io_context
structure, so remove tht.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
All the bios that index_one_bio operates on are the bios submitted by the
upper layer. These are never resubmitted to an actual device by the
raid56 code, and thus the iter never changes from the initial state.
Thus we can always just use bi_iter directly as it will be the same as
the saved copy.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
If we have a btrfs image with dirty log, along with an unsupported RO
compatible flag:
log_root 30474240
...
compat_flags 0x0
compat_ro_flags 0x40000003
( FREE_SPACE_TREE |
FREE_SPACE_TREE_VALID |
unknown flag: 0x40000000 )
Then even if we can only mount it RO, we will still cause metadata
update for log replay:
BTRFS info (device dm-1): flagging fs with big metadata feature
BTRFS info (device dm-1): using free space tree
BTRFS info (device dm-1): has skinny extents
BTRFS info (device dm-1): start tree-log replay
This is definitely against RO compact flag requirement.
[CAUSE]
RO compact flag only forces us to do RO mount, but we will still do log
replay for plain RO mount.
Thus this will result us to do log replay and update metadata.
This can be very problematic for new RO compat flag, for example older
kernel can not understand v2 cache, and if we allow metadata update on
RO mount and invalidate/corrupt v2 cache.
[FIX]
Just reject the mount unless rescue=nologreplay is provided:
BTRFS error (device dm-1): cannot replay dirty log with unsupport optional features (0x40000000), try rescue=nologreplay instead
We don't want to set rescue=nologreply directly, as this would make the
end user to read the old data, and cause confusion.
Since the such case is really rare, we're mostly fine to just reject the
mount with an error message, which also includes the proper workaround.
CC: stable@vger.kernel.org #4.9+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When using "btrfs inspect-internal dump-super" to inspect an fs with
dirty log, it always shows the log_root_transid as 0:
log_root 30474240
log_root_transid 0 <<<
log_root_level 0
It turns out that, btrfs_super_block::log_root_transid is never really
utilized (even no read for it).
This can date back to the introduction of btrfs into upstream kernel.
In fact, when reading log tree root, we always use
btrfs_super_block::generation + 1 as the expected generation.
So here we're completely safe to mark this member deprecated.
In theory we can easily reuse this member for other purposes, but to be
extra safe, here we follow the leafsize way, by adding "__unused_" for
log_root_transid.
And we can safely remove the accessors, since there is no such callers
from the very beginning.
Reviewed-by: Filipe Manana <fdmanana@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>
submit_one_bio always works on the bio and compression flags from a
btrfs_bio_ctrl structure. Pass the explicitly and clean up the
calling conventions by handling a NULL bio in submit_one_bio, and
using the btrfs_bio_ctrl to pass the mirror number as well.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Merge end_write_bio and flush_write_bio into a single submit_write_bio
helper, that either submits the bio or ends it if a negative errno was
passed in. This consolidates a lot of duplicated checks in the callers.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
submit_one_bio is only used for page cache I/O, so the inode can be
trivially derived from the first page in the bio.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are two separate checks in the bounds checker, the first one being
a special case of the second. As this function is performance critical
due to checking access to any eb member, reducing the size can slightly
improve performance.
On a release build on x86_64 the helper is completely inlined so the
function call overhead is also gone.
There was a report of 5% performance drop on metadata heavy workload,
that disappeared after disabling asserts. The most significant part of
that is the bounds checker.
https://lore.kernel.org/linux-btrfs/20200724164147.39925-1-josef@toxicpanda.com/
After the analysis, the optimized code removes the worst overhead which
is the function call and the performance was restored.
https://lore.kernel.org/linux-btrfs/20200730110943.GE3703@twin.jikos.cz/
1. baseline, asserts on, setget check on
run time: 46s
run time with perf: 48s
2. asserts on, comment out setget check
run time: 44s
run time with perf: 47s
So this is confirms the 5% difference
3. asserts on, optimized seget check
run time: 44s
run time with perf: 47s
The optimizations are reducing the number of ifs to 1 and inlining the
hot path. Low-level stuff, gets the performance back. Patch below.
4. asserts off, no setget check
run time: 44s
run time with perf: 45s
This verifies that asserts other than the setget check have negligible
impact on performance and it's not harmful to keep them on.
Analysis where the performance is lost:
* check_setget_bounds is short function, but it's still a function call,
changing the flow of instructions and given how many times it's
called the overhead adds up
* there are two conditions, one to check if the range is
completely outside (member_offset > eb->len) or partially inside
(member_offset + size > eb->len)
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The use of kmap() is being deprecated in favor of kmap_local_page() where
it is feasible. With kmap_local_page(), the mapping is per thread, CPU
local and not globally visible.
Therefore, use kmap_local_page() / kunmap_local() in lzo.c wherever the
mappings are per thread and not globally visible.
Tested on QEMU + KVM 32 bits VM with 4GB of RAM and HIGHMEM64G enabled.
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The use of kmap() is being deprecated in favor of kmap_local_page() where
it is feasible. With kmap_local_page(), the mapping is per thread, CPU
local and not globally visible.
Therefore, use kmap_local_page() / kunmap_local() in inode.c wherever the
mappings are per thread and not globally visible.
Tested on QEMU + KVM 32 bits VM with 4GB of RAM and HIGHMEM64G enabled.
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The bios submitted from btrfs_map_bio don't really interact with the
rest of btrfs and the only btrfs_bio member actually used in the
low-level bios is the pointer to the btrfs_io_context used for endio
handler.
Use a union in struct btrfs_io_stripe that allows the endio handler to
find the btrfs_io_context and remove the spurious ->device assignment
so that a plain fs_bio_set bio can be used for the low-level bios
allocated inside btrfs_map_bio.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Move all per-stripe handling into submit_stripe_bio and use a label to
cleanup instead of duplicating the logic.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
All reads bio that go through btrfs_map_bio need to be completed in
user context. And read I/Os are the most common and timing critical
in almost any file system workloads.
Embed a work_struct into struct btrfs_bio and use it to complete all
read bios submitted through btrfs_map, using the REQ_META flag to decide
which workqueue they are placed on.
This removes the need for a separate 128 byte allocation (typically
rounded up to 192 bytes by slab) for all reads with a size increase
of 24 bytes for struct btrfs_bio. Future patches will reorganize
struct btrfs_bio to make use of this extra space for writes as well.
(All sizes are based a on typical 64-bit non-debug build)
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Set REQ_META in btrfs_submit_metadata_bio instead of the various callers.
We'll start relying on this flag inside of btrfs in a bit, and this
ensures it is always set correctly.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Compressed write bio completion is the only user of btrfs_bio_wq_end_io
for writes, and the use of btrfs_bio_wq_end_io is a little suboptimal
here as we only real need user context for the final completion of a
compressed_bio structure, and not every single bio completion.
Add a work_struct to struct compressed_bio instead and use that to call
finish_compressed_bio_write. This allows to remove all handling of
write bios in the btrfs_bio_wq_end_io infrastructure.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
The bio completion handler of the bio used for the compressed data is
already run in a workqueue using btrfs_bio_wq_end_io, so don't schedule
the completion of the original bio to the same workqueue again but just
execute it directly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead of attaching an extra allocation an indirect call to each
low-level bio issued by the RAID code, add a work_struct to struct
btrfs_raid_bio and only defer the per-rbio completion action. The
per-bio action for all the I/Os are trivial and can be safely done
from interrupt context.
As a nice side effect this also allows sharing the boilerplate code
for the per-bio completions
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Split btrfs_submit_data_bio into one helper for reads and one for writes.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There is no exit block and cleanup and the function is reasonably short
so we can use inline return and not the goto. This makes the function
more straight forward.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Assign ->mirror_num and ->bi_status in btrfs_end_bioc instead of
duplicating the logic in the callers. Also remove the bio argument as
it always must be bioc->orig_bio and the now pointless bioc_error that
did nothing but assign bi_sector to the same value just sampled in the
caller.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that the new support is implemented, allow the ioctl to accept v2
and the compressed flag, and update the version in sysfs.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that all of the pieces are in place, we can use the ENCODED_WRITE
command to send compressed extents when appropriate.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
For encoded writes in send v2, we will get the encoded data with
btrfs_encoded_read_regular_fill_pages(), which expects a list of raw
pages. To avoid extra buffers and copies, we should read directly into
the send buffer. Therefore, we need the raw pages for the send buffer.
We currently allocate the send buffer with kvmalloc(), which may return
a kmalloc'd buffer or a vmalloc'd buffer. For vmalloc, we can get the
pages with vmalloc_to_page(). For kmalloc, we could use virt_to_page().
However, the buffer size we use (144K) is not a power of two, which in
theory is not guaranteed to return a page-aligned buffer, and in
practice would waste a lot of memory due to rounding up to the next
power of two. 144K is large enough that it usually gets allocated with
vmalloc(), anyways. So, for send v2, replace kvmalloc() with vmalloc()
and save the pages in an array.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The length field of the send stream TLV header is 16 bits. This means
that the maximum amount of data that can be sent for one write is 64K
minus one. However, encoded writes must be able to send the maximum
compressed extent (128K) in one command, or more. To support this, send
stream version 2 encodes the DATA attribute differently: it has no
length field, and the length is implicitly up to the end of containing
command (which has a 32bit length field). Although this is necessary
for encoded writes, normal writes can benefit from it, too.
Also add a check to enforce that the DATA attribute is last. It is only
strictly necessary for v2, but we might as well make v1 consistent with
it.
For v2, let's bump up the send buffer to the maximum compressed extent
size plus 16K for the other metadata (144K total). Since this will most
likely be vmalloc'd (and always will be after the next commit), we round
it up to the next page since we might as well use the rest of the page
on systems with >16K pages.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This adds the definitions of the new commands for send stream version 2
and their respective attributes: fallocate, FS_IOC_SETFLAGS (a.k.a.
chattr), and encoded writes. It also documents two changes to the send
stream format in v2: the receiver shouldn't assume a maximum command
size, and the DATA attribute is encoded differently to allow for writes
larger than 64k. These will be implemented in subsequent changes, and
then the ioctl will accept the new version and flag.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Commit e77fbf9903 ("btrfs: send: prepare for v2 protocol") added
_BTRFS_SEND_C_MAX_V* macros equal to the maximum command number for the
version plus 1, but as written this creates gaps in the number space.
The maximum command number is currently 22, and __BTRFS_SEND_C_MAX_V1 is
accordingly 23. But then __BTRFS_SEND_C_MAX_V2 is 24, suggesting that v2
has a command numbered 23, and __BTRFS_SEND_C_MAX is 25, suggesting that
23 and 24 are valid commands.
Instead, let's explicitly number all of the commands, attributes, and
sentinel MAX constants.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We collect these statistics but have never exposed them in any way. I
also didn't find any patches that ever attempted to make use of them.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Adds write-only trigger to force new chunk allocation for a given block
group type. It is at
/sys/fs/btrfs/<uuid>/allocation/<type>/force_chunk_alloc
Note: this is now only for debugging and testing and is enabled with the
CONFIG_BTRFS_DEBUG configuration option. The transaction is
started from sysfs context and can be problematic in some cases.
Signed-off-by: Stefan Roesch <shr@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ Changes from the original submission:
- update changelog
- drop unnecessary error messages
- switch value to bool and use kstrtobool
- move BTRFS_ATTR_W definition
- add comment for using transaction
]
Signed-off-by: David Sterba <dsterba@suse.com>
Add new sysfs knob
/sys/fs/btrfs/<uuid>/allocation/<type>/chunk_size.
This allows to query the chunk size and also set the chunk size.
Constraints:
- can be changed by root only
- system chunk size can't be set
- maximum chunk size is 10% of the filesystem size
- final value is rounded down to a multiple of 256M
- cannot be set on zoned filesystem
Note, that rounding and the 10% clamp will result to a different value
on filesystems smaller than 10G, typically 768M.
Signed-off-by: Stefan Roesch <shr@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ Changes to original submission:
- document setting constraints
- drop read-only requirement
- drop unnecessary error messages
- fix return values of _store callback
- use memparse for the value
- fix rounding down to 256M
]
Signed-off-by: David Sterba <dsterba@suse.com>
The chunk size is stored in the btrfs_space_info structure. It is
initialized at the start and is then used.
A new API is added to update the current chunk size. This API is used
to be able to expose the chunk_size as a sysfs setting.
Signed-off-by: Stefan Roesch <shr@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ rename and merge helpers, switch atomic type to u64, style fixes ]
Signed-off-by: David Sterba <dsterba@suse.com>
While running generic/475 in a loop I got the following error
BTRFS critical (device dm-11): corrupt leaf: root=5 block=31096832 slot=69, bad key order, prev (263 96 531) current (263 96 524)
<snip>
item 65 key (263 96 517) itemoff 14132 itemsize 33
item 66 key (263 96 523) itemoff 14099 itemsize 33
item 67 key (263 96 525) itemoff 14066 itemsize 33
item 68 key (263 96 531) itemoff 14033 itemsize 33
item 69 key (263 96 524) itemoff 14000 itemsize 33
As you can see here we have 3 dir index keys with the dir index value of
523, 524, and 525 inserted between 517 and 524. This occurs because our
dir index insertion code will bulk insert all dir index items on the
node regardless of their actual key value.
This makes sense on a normally running system, because if there's a gap
in between the items there was a deletion before the item was inserted,
so there's not going to be an overlap of the dir index items that need
to be inserted and what exists on disk.
However during log replay this isn't necessarily true, we could have any
number of dir indexes in the tree already.
Fix this by seeing if we're replaying the log, and if we are simply skip
batching if there's a gap in the key space.
This file system was left broken from the fstest, I tested this patch
against the broken fs to make sure it replayed the log properly, and
then btrfs checked the file system after the log replay to verify
everything was ok.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Whenever we want to create a new dir index item (when creating an inode,
create a hard link, rename a file) we reserve 1 unit of metadata space
for it in a transaction (that's 256K for a node/leaf size of 16K), and
then create a delayed insertion item for it to be added later to the
subvolume's tree. That unit of metadata is kept until the delayed item
is inserted into the subvolume tree, which may take a while to happen
(in the worst case, it's done only when the transaction commits). If we
have multiple dir index items to insert for the same directory, say N
index items, and they all fit in a single leaf of metadata, then we are
holding N units of reserved metadata space when all we need is 1 unit.
This change addresses that, whenever a new delayed dir index item is
added, we release the unit of metadata the caller has reserved when it
started the transaction if adding that new dir index item does not
result in touching one more metadata leaf, otherwise the reservation
is kept by transferring it from the transaction block reserve to the
delayed items block reserve, just like before. Given that with a leaf
size of 16K we can have a few hundred dir index items in a single leaf
(the exact value depends on file name lengths), this reduces pressure on
metadata reservation by releasing unnecessary space much sooner.
The following fs_mark test showed some improvement when creating many
files in parallel on machine running a non debug kernel (debian's default
kernel config) with 12 cores:
$ cat test.sh
#!/bin/bash
DEV=/dev/nvme0n1
MNT=/mnt/nvme0n1
MOUNT_OPTIONS="-o ssd"
FILES=100000
THREADS=$(nproc --all)
echo "performance" | \
tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor
mkfs.btrfs -f $DEV
mount $MOUNT_OPTIONS $DEV $MNT
OPTS="-S 0 -L 10 -n $FILES -s 0 -t $THREADS -k"
for ((i = 1; i <= $THREADS; i++)); do
OPTS="$OPTS -d $MNT/d$i"
done
fs_mark $OPTS
umount $MNT
Before:
FSUse% Count Size Files/sec App Overhead
2 1200000 0 225991.3 5465891
4 2400000 0 345728.1 5512106
4 3600000 0 346959.5 5557653
8 4800000 0 329643.0 5587548
8 6000000 0 312657.4 5606717
8 7200000 0 281707.5 5727985
12 8400000 0 88309.8 5020422
12 9600000 0 85835.9 5207496
16 10800000 0 81039.2 5404964
16 12000000 0 58548.6 5842468
After:
FSUse% Count Size Files/sec App Overhead
2 1200000 0 230604.5 5778375
4 2400000 0 348908.3 5508072
4 3600000 0 357028.7 5484337
6 4800000 0 342898.3 5565703
6 6000000 0 314670.8 5751555
8 7200000 0 282548.2 5778177
12 8400000 0 90844.9 5306819
12 9600000 0 86963.1 5304689
16 10800000 0 89113.2 5455248
16 12000000 0 86693.5 5518933
The "after" results are after applying this patch and all the other
patches in the same patchset, which is comprised of the following
changes:
btrfs: balance btree dirty pages and delayed items after a rename
btrfs: free the path earlier when creating a new inode
btrfs: balance btree dirty pages and delayed items after clone and dedupe
btrfs: add assertions when deleting batches of delayed items
btrfs: deal with deletion errors when deleting delayed items
btrfs: refactor the delayed item deletion entry point
btrfs: improve batch deletion of delayed dir index items
btrfs: assert that delayed item is a dir index item when adding it
btrfs: improve batch insertion of delayed dir index items
btrfs: do not BUG_ON() on failure to reserve metadata for delayed item
btrfs: set delayed item type when initializing it
btrfs: reduce amount of reserved metadata for delayed item insertion
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently we set the type of a delayed item only after successfully
inserting it into its respective rbtree. This is fine, as the type
is not used anywhere before that point, but for the next patch in the
series, there will be the need to check the type of a delayed item
before inserting it into a rbtree.
So set the type of a delayed item immediately after allocating it.
This also makes the trivial wrappers for adding insertion and deletion
useless, so it removes them as well.
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>
At btrfs_insert_delayed_dir_index(), we don't expect the metadata
reservation for the delayed dir index item insertion to fail, because the
caller is supposed to have reserved 1 unit of metadata space for that.
All callers are able to deal with an error in case that happens, so there
is no need for something so drastic as a BUG_ON() in case of failure.
Instead just emit a warning, so that's easily noticed during development
(fstests in particular), and return the error to the caller.
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>
