btrfs_ioctl_get_subvol_info() frees the search path after the userspace
copy from the temp buffer @subvol_info. This can lead to a lock splat
warning.
Fix this by freeing the path before we copy it to userspace.
CC: stable@vger.kernel.org # 4.19+
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_ioctl_ino_to_path() frees the search path after the userspace copy
from the temp buffer @ipath->fspath. Which potentially can lead to a lock
splat warning.
Fix this by freeing the path before we copy it to userspace.
CC: stable@vger.kernel.org # 4.19+
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_ioctl_logical_to_ino() frees the search path after the userspace
copy from the temp buffer @inodes. Which potentially can lead to a lock
splat.
Fix this by freeing the path before we copy @inodes to userspace.
CC: stable@vger.kernel.org # 4.19+
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead of taking up a whole argument to indicate we're clearing
everything in a range, simply add another EXTENT bit to control this,
and then update all the callers to drop this argument from the
clear_extent_bit variants.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We have two variants of lock/unlock extent, one set that takes a cached
state, another that does not. This is slightly annoying, and generally
speaking there are only a few places where we don't have a cached state.
Simplify this by making lock_extent/unlock_extent the only variant and
make it take a cached state, then convert all the callers appropriately.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is only used in the case that we are clearing EXTENT_LOCKED, so
infer this value from the bits passed in instead of taking it as an
argument.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.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>
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>
This eliminates 2 labels and makes the code generally more streamlined.
Also rename the 'out_bargs' label to 'out_unlock' since bargs is going
to be freed under the 'out' label. This also fixes a memory leak since
bargs wasn't correctly freed in one of the condition which are now moved
in btrfs_try_lock_balance.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This function contains the factored out locking sequence of
btrfs_ioctl_balance. Having this piece of code separate helps to
simplify btrfs_ioctl_balance which has too complicated. This will be
used in the next patch to streamline the logic in btrfs_ioctl_balance.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
- Appoint myself page cache maintainer
- Fix how scsicam uses the page cache
- Use the memalloc_nofs_save() API to replace AOP_FLAG_NOFS
- Remove the AOP flags entirely
- Remove pagecache_write_begin() and pagecache_write_end()
- Documentation updates
- Convert several address_space operations to use folios:
- is_dirty_writeback
- readpage becomes read_folio
- releasepage becomes release_folio
- freepage becomes free_folio
- Change filler_t to require a struct file pointer be the first argument
like ->read_folio
-----BEGIN PGP SIGNATURE-----
iQEzBAABCgAdFiEEejHryeLBw/spnjHrDpNsjXcpgj4FAmKNMDUACgkQDpNsjXcp
gj4/mwf/bpHhXH4ZoNIvtUpTF6rZbqeffmc0VrbxCZDZ6igRnRPglxZ9H9v6L53O
7B0FBQIfxgNKHZpdqGdOkv8cjg/GMe/HJUbEy5wOakYPo4L9fZpHbDZ9HM2Eankj
xBqLIBgBJ7doKr+Y62DAN19TVD8jfRfVtli5mqXJoNKf65J7BkxljoTH1L3EXD9d
nhLAgyQjR67JQrT/39KMW+17GqLhGefLQ4YnAMONtB6TVwX/lZmigKpzVaCi4r26
bnk5vaR/3PdjtNxIoYvxdc71y2Eg05n2jEq9Wcy1AaDv/5vbyZUlZ2aBSaIVbtKX
WfrhN9O3L0bU5qS7p9PoyfLc9wpq8A==
=djLv
-----END PGP SIGNATURE-----
Merge tag 'folio-5.19' of git://git.infradead.org/users/willy/pagecache
Pull page cache updates from Matthew Wilcox:
- Appoint myself page cache maintainer
- Fix how scsicam uses the page cache
- Use the memalloc_nofs_save() API to replace AOP_FLAG_NOFS
- Remove the AOP flags entirely
- Remove pagecache_write_begin() and pagecache_write_end()
- Documentation updates
- Convert several address_space operations to use folios:
- is_dirty_writeback
- readpage becomes read_folio
- releasepage becomes release_folio
- freepage becomes free_folio
- Change filler_t to require a struct file pointer be the first
argument like ->read_folio
* tag 'folio-5.19' of git://git.infradead.org/users/willy/pagecache: (107 commits)
nilfs2: Fix some kernel-doc comments
Appoint myself page cache maintainer
fs: Remove aops->freepage
secretmem: Convert to free_folio
nfs: Convert to free_folio
orangefs: Convert to free_folio
fs: Add free_folio address space operation
fs: Convert drop_buffers() to use a folio
fs: Change try_to_free_buffers() to take a folio
jbd2: Convert release_buffer_page() to use a folio
jbd2: Convert jbd2_journal_try_to_free_buffers to take a folio
reiserfs: Convert release_buffer_page() to use a folio
fs: Remove last vestiges of releasepage
ubifs: Convert to release_folio
reiserfs: Convert to release_folio
orangefs: Convert to release_folio
ocfs2: Convert to release_folio
nilfs2: Remove comment about releasepage
nfs: Convert to release_folio
jfs: Convert to release_folio
...
-----BEGIN PGP SIGNATURE-----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=lv6P
-----END PGP SIGNATURE-----
Merge tag 'for-5.19-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs updates from David Sterba:
"Features:
- subpage:
- support for PAGE_SIZE > 4K (previously only 64K)
- make it work with raid56
- repair super block num_devices automatically if it does not match
the number of device items
- defrag can convert inline extents to regular extents, up to now
inline files were skipped but the setting of mount option
max_inline could affect the decision logic
- zoned:
- minimal accepted zone size is explicitly set to 4MiB
- make zone reclaim less aggressive and don't reclaim if there are
enough free zones
- add per-profile sysfs tunable of the reclaim threshold
- allow automatic block group reclaim for non-zoned filesystems, with
sysfs tunables
- tree-checker: new check, compare extent buffer owner against owner
rootid
Performance:
- avoid blocking on space reservation when doing nowait direct io
writes (+7% throughput for reads and writes)
- NOCOW write throughput improvement due to refined locking (+3%)
- send: reduce pressure to page cache by dropping extent pages right
after they're processed
Core:
- convert all radix trees to xarray
- add iterators for b-tree node items
- support printk message index
- user bulk page allocation for extent buffers
- switch to bio_alloc API, use on-stack bios where convenient, other
bio cleanups
- use rw lock for block groups to favor concurrent reads
- simplify workques, don't allocate high priority threads for all
normal queues as we need only one
- refactor scrub, process chunks based on their constraints and
similarity
- allocate direct io structures on stack and pass around only
pointers, avoids allocation and reduces potential error handling
Fixes:
- fix count of reserved transaction items for various inode
operations
- fix deadlock between concurrent dio writes when low on free data
space
- fix a few cases when zones need to be finished
VFS, iomap:
- add helper to check if sb write has started (usable for assertions)
- new helper iomap_dio_alloc_bio, export iomap_dio_bio_end_io"
* tag 'for-5.19-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (173 commits)
btrfs: zoned: introduce a minimal zone size 4M and reject mount
btrfs: allow defrag to convert inline extents to regular extents
btrfs: add "0x" prefix for unsupported optional features
btrfs: do not account twice for inode ref when reserving metadata units
btrfs: zoned: fix comparison of alloc_offset vs meta_write_pointer
btrfs: send: avoid trashing the page cache
btrfs: send: keep the current inode open while processing it
btrfs: allocate the btrfs_dio_private as part of the iomap dio bio
btrfs: move struct btrfs_dio_private to inode.c
btrfs: remove the disk_bytenr in struct btrfs_dio_private
btrfs: allocate dio_data on stack
iomap: add per-iomap_iter private data
iomap: allow the file system to provide a bio_set for direct I/O
btrfs: add a btrfs_dio_rw wrapper
btrfs: zoned: zone finish unused block group
btrfs: zoned: properly finish block group on metadata write
btrfs: zoned: finish block group when there are no more allocatable bytes left
btrfs: zoned: consolidate zone finish functions
btrfs: zoned: introduce btrfs_zoned_bg_is_full
btrfs: improve error reporting in lookup_inline_extent_backref
...
- Initial support for the ARMv9 Scalable Matrix Extension (SME). SME
takes the approach used for vectors in SVE and extends this to provide
architectural support for matrix operations. No KVM support yet, SME
is disabled in guests.
- Support for crashkernel reservations above ZONE_DMA via the
'crashkernel=X,high' command line option.
- btrfs search_ioctl() fix for live-lock with sub-page faults.
- arm64 perf updates: support for the Hisilicon "CPA" PMU for monitoring
coherent I/O traffic, support for Arm's CMN-650 and CMN-700
interconnect PMUs, minor driver fixes, kerneldoc cleanup.
- Kselftest updates for SME, BTI, MTE.
- Automatic generation of the system register macros from a 'sysreg'
file describing the register bitfields.
- Update the type of the function argument holding the ESR_ELx register
value to unsigned long to match the architecture register size
(originally 32-bit but extended since ARMv8.0).
- stacktrace cleanups.
- ftrace cleanups.
- Miscellaneous updates, most notably: arm64-specific huge_ptep_get(),
avoid executable mappings in kexec/hibernate code, drop TLB flushing
from get_clear_flush() (and rename it to get_clear_contig()),
ARCH_NR_GPIO bumped to 2048 for ARCH_APPLE.
-----BEGIN PGP SIGNATURE-----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=0DjE
-----END PGP SIGNATURE-----
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Catalin Marinas:
- Initial support for the ARMv9 Scalable Matrix Extension (SME).
SME takes the approach used for vectors in SVE and extends this to
provide architectural support for matrix operations. No KVM support
yet, SME is disabled in guests.
- Support for crashkernel reservations above ZONE_DMA via the
'crashkernel=X,high' command line option.
- btrfs search_ioctl() fix for live-lock with sub-page faults.
- arm64 perf updates: support for the Hisilicon "CPA" PMU for
monitoring coherent I/O traffic, support for Arm's CMN-650 and
CMN-700 interconnect PMUs, minor driver fixes, kerneldoc cleanup.
- Kselftest updates for SME, BTI, MTE.
- Automatic generation of the system register macros from a 'sysreg'
file describing the register bitfields.
- Update the type of the function argument holding the ESR_ELx register
value to unsigned long to match the architecture register size
(originally 32-bit but extended since ARMv8.0).
- stacktrace cleanups.
- ftrace cleanups.
- Miscellaneous updates, most notably: arm64-specific huge_ptep_get(),
avoid executable mappings in kexec/hibernate code, drop TLB flushing
from get_clear_flush() (and rename it to get_clear_contig()),
ARCH_NR_GPIO bumped to 2048 for ARCH_APPLE.
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (145 commits)
arm64/sysreg: Generate definitions for FAR_ELx
arm64/sysreg: Generate definitions for DACR32_EL2
arm64/sysreg: Generate definitions for CSSELR_EL1
arm64/sysreg: Generate definitions for CPACR_ELx
arm64/sysreg: Generate definitions for CONTEXTIDR_ELx
arm64/sysreg: Generate definitions for CLIDR_EL1
arm64/sve: Move sve_free() into SVE code section
arm64: Kconfig.platforms: Add comments
arm64: Kconfig: Fix indentation and add comments
arm64: mm: avoid writable executable mappings in kexec/hibernate code
arm64: lds: move special code sections out of kernel exec segment
arm64/hugetlb: Implement arm64 specific huge_ptep_get()
arm64/hugetlb: Use ptep_get() to get the pte value of a huge page
arm64: kdump: Do not allocate crash low memory if not needed
arm64/sve: Generate ZCR definitions
arm64/sme: Generate defintions for SVCR
arm64/sme: Generate SMPRI_EL1 definitions
arm64/sme: Automatically generate SMPRIMAP_EL2 definitions
arm64/sme: Automatically generate SMIDR_EL1 defines
arm64/sme: Automatically generate defines for SMCR
...
Btrfs defaults to max_inline=2K to make small writes inlined into
metadata.
The default value is always a win, as even DUP/RAID1/RAID10 doubles the
metadata usage, it should still cause less physical space used compared
to a 4K regular extents.
But since the introduction of RAID1C3 and RAID1C4 it's no longer the case,
users may find inlined extents causing too much space wasted, and want
to convert those inlined extents back to regular extents.
Unfortunately defrag will unconditionally skip all inline extents, no
matter if the user is trying to converting them back to regular extents.
So this patch will add a small exception for defrag_collect_targets() to
allow defragging inline extents, if and only if the inlined extents are
larger than max_inline, allowing users to convert them to regular ones.
This also allows us to defrag extents like the following:
item 6 key (257 EXTENT_DATA 0) itemoff 15794 itemsize 69
generation 7 type 0 (inline)
inline extent data size 48 ram_bytes 4096 compression 1 (zlib)
item 7 key (257 EXTENT_DATA 4096) itemoff 15741 itemsize 53
generation 7 type 1 (regular)
extent data disk byte 13631488 nr 4096
extent data offset 0 nr 16384 ram 16384
extent compression 1 (zlib)
Previously we're unable to do any defrag, since the first extent is
inlined, and the second one has no extent to merge.
Now we can defrag it to just one single extent, saving 48 bytes metadata
space.
item 6 key (257 EXTENT_DATA 0) itemoff 15810 itemsize 53
generation 8 type 1 (regular)
extent data disk byte 13635584 nr 4096
extent data offset 0 nr 20480 ram 20480
extent compression 1 (zlib)
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Explicit type casts are not necessary when it's void* to another pointer
type.
Signed-off-by: Yu Zhe <yuzhe@nfschina.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Move code in btrfs_ioctl_balance to simplify its flow. This is
possible thanks to the removal of balance v1 ioctl and ensuring 'arg'
argument is always present. First move the code duplicating the
userspace arg to the kernel 'barg'. This makes the out_unlock label
redundant. Secondly, check the validity of bargs::flags before copying
to the dynamically allocated 'bctl'. This removes the need for the
out_bctl label.
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
With the removal of balance v1 ioctl the 'arg' argument is guaranteed to
be present so simply remove all conditional code which checks for its
presence.
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
All of our inode creation code paths duplicate the calls to
btrfs_init_inode_security() and btrfs_add_link(). Subvolume creation
additionally duplicates property inheritance and the call to
btrfs_set_inode_index(). Fix this by moving the common code into
btrfs_create_new_inode(). This accomplishes a few things at once:
1. It reduces code duplication.
2. It allows us to set up the inode completely before inserting the
inode item, removing calls to btrfs_update_inode().
3. It fixes a leak of an inode on disk in some error cases. For example,
in btrfs_create(), if btrfs_new_inode() succeeds, then we have
inserted an inode item and its inode ref. However, if something after
that fails (e.g., btrfs_init_inode_security()), then we end the
transaction and then decrement the link count on the inode. If the
transaction is committed and the system crashes before the failed
inode is deleted, then we leak that inode on disk. Instead, this
refactoring aborts the transaction when we can't recover more
gracefully.
4. It exposes various ways that subvolume creation diverges from mkdir
in terms of inheriting flags, properties, permissions, and POSIX
ACLs, a lot of which appears to be accidental. This patch explicitly
does _not_ change the existing non-standard behavior, but it makes
those differences more clear in the code and documents them so that
we can discuss whether they should be changed.
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The various inode creation code paths do not account for the compression
property, POSIX ACLs, or the parent inode item when starting a
transaction. Fix it by refactoring all of these code paths to use a new
function, btrfs_new_inode_prepare(), which computes the correct number
of items. To do so, it needs to know whether POSIX ACLs will be created,
so move the ACL creation into that function. To reduce the number of
arguments that need to be passed around for inode creation, define
struct btrfs_new_inode_args containing all of the relevant information.
btrfs_new_inode_prepare() will also be a good place to set up the
fscrypt context and encrypted filename in the future.
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead of calling new_inode() and inode_init_owner() inside of
btrfs_new_inode(), do it in the callers. This allows us to pass in just
the inode instead of the mnt_userns and mode and removes the need for
memalloc_nofs_{save,restores}() since we do it before starting a
transaction. In create_subvol(), it also means we no longer have to look
up the inode again to instantiate it. This also paves the way for some
more cleanups in later patches.
This also removes the comments about Smack checking i_op, which are no
longer true since commit 5d6c31910b ("xattr: Add
__vfs_{get,set,remove}xattr helpers"). Now it checks inode->i_opflags &
IOP_XATTR, which is set based on sb->s_xattr.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When btrfs_qgroup_inherit(), btrfs_alloc_tree_block, or
btrfs_insert_root() fail in create_subvol(), we return without freeing
anon_dev. Reorganize the error handling in create_subvol() to fix this.
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is a "weak" conversion which converts straight back to using pages.
A full conversion should be performed at some point, hopefully by
someone familiar with the filesystem.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Commit a48b73eca4 ("btrfs: fix potential deadlock in the search
ioctl") addressed a lockdep warning by pre-faulting the user pages and
attempting the copy_to_user_nofault() in an infinite loop. On
architectures like arm64 with MTE, an access may fault within a page at
a location different from what fault_in_writeable() probed. Since the
sk_offset is rewound to the previous struct btrfs_ioctl_search_header
boundary, there is no guaranteed forward progress and search_ioctl() may
live-lock.
Use fault_in_subpage_writeable() instead of fault_in_writeable() to
ensure the permission is checked at the right granularity (smaller than
PAGE_SIZE).
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Fixes: a48b73eca4 ("btrfs: fix potential deadlock in the search ioctl")
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: David Sterba <dsterba@suse.com>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/r/20220423100751.1870771-4-catalin.marinas@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Abstract away implementation details from file systems by providing a
block_device based helper to retrieve the discard granularity.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> [drbd]
Acked-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Acked-by: David Sterba <dsterba@suse.com> [btrfs]
Link: https://lore.kernel.org/r/20220415045258.199825-26-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Just use a non-zero max_discard_sectors as an indicator for discard
support, similar to what is done for write zeroes.
The only places where needs special attention is the RAID5 driver,
which must clear discard support for security reasons by default,
even if the default stacking rules would allow for it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> [drbd]
Acked-by: Jan Höppner <hoeppner@linux.ibm.com> [s390]
Acked-by: Coly Li <colyli@suse.de> [bcache]
Acked-by: David Sterba <dsterba@suse.com> [btrfs]
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-25-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
It was scheduled for removal in kernel v5.18 commit 6c405b2409
("btrfs: deprecate BTRFS_IOC_BALANCE ioctl") thus its time has come.
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
There is a report that autodefrag is defragging single sector, which
is completely waste of IO, and no help for defragging:
btrfs-cleaner-808 defrag_one_locked_range: root=256 ino=651122 start=0 len=4096
[CAUSE]
In defrag_collect_targets(), we check if the current range (A) can be merged
with next one (B).
If mergeable, we will add range A into target for defrag.
However there is a catch for autodefrag, when checking mergeability
against range B, we intentionally pass 0 as @newer_than, hoping to get a
higher chance to merge with the next extent.
But in the next iteration, range B will looked up by defrag_lookup_extent(),
with non-zero @newer_than.
And if range B is not really newer, it will rejected directly, causing
only range A being defragged, while we expect to defrag both range A and
B.
[FIX]
Since the root cause is the difference in check condition of
defrag_check_next_extent() and defrag_collect_targets(), we fix it by:
1. Pass @newer_than to defrag_check_next_extent()
2. Pass @extent_thresh to defrag_check_next_extent()
This makes the check between defrag_collect_targets() and
defrag_check_next_extent() more consistent.
While there is still some minor difference, the remaining checks are
focus on runtime flags like writeback/delalloc, which are mostly
transient and safe to be checked only in defrag_collect_targets().
Link: https://github.com/btrfs/linux/issues/423#issuecomment-1066981856
CC: stable@vger.kernel.org # 5.16+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The implementation resembles direct I/O: we have to flush any ordered
extents, invalidate the page cache, and do the io tree/delalloc/extent
map/ordered extent dance. From there, we can reuse the compression code
with a minor modification to distinguish the write from writeback. This
also creates inline extents when possible.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are 4 main cases:
1. Inline extents: we copy the data straight out of the extent buffer.
2. Hole/preallocated extents: we fill in zeroes.
3. Regular, uncompressed extents: we read the sectors we need directly
from disk.
4. Regular, compressed extents: we read the entire compressed extent
from disk and indicate what subset of the decompressed extent is in
the file.
This initial implementation simplifies a few things that can be improved
in the future:
- Cases 1, 3, and 4 allocate temporary memory to read into before
copying out to userspace.
- We don't do read repair, because it turns out that read repair is
currently broken for compressed data.
- We hold the inode lock during the operation.
Note that we don't need to hold the mmap lock. We may race with
btrfs_page_mkwrite() and read the old data from before the page was
dirtied:
btrfs_page_mkwrite btrfs_encoded_read
---------------------------------------------------
(enter) (enter)
btrfs_wait_ordered_range
lock_extent_bits
btrfs_page_set_dirty
unlock_extent_cached
(exit)
lock_extent_bits
read extent (dirty page hasn't been flushed,
so this is the old data)
unlock_extent_cached
(exit)
we read the old data from before the page was dirtied. But, that's true
even if we were to hold the mmap lock:
btrfs_page_mkwrite btrfs_encoded_read
-------------------------------------------------------------------
(enter) (enter)
btrfs_inode_lock(BTRFS_ILOCK_MMAP)
down_read(i_mmap_lock) (blocked)
btrfs_wait_ordered_range
lock_extent_bits
read extent (page hasn't been dirtied,
so this is the old data)
unlock_extent_cached
btrfs_inode_unlock(BTRFS_ILOCK_MMAP)
down_read(i_mmap_lock) returns
lock_extent_bits
btrfs_page_set_dirty
unlock_extent_cached
In other words, this is inherently racy, so it's fine that we return the
old data in this tiny window.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The static_assert introduced in 6bab69c650 ("build_bug.h: add wrapper
for _Static_assert") has been supported by compilers for a long time
(gcc 4.6, clang 3.0) and can be used in header files. We don't need to
put BUILD_BUG_ON to random functions but rather keep it next to the
definition.
The exception here is the UAPI header btrfs_tree.h that could be
potentially included by userspace code and the static assert is not
defined (nor used in any other header).
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When we stop tracking metadata blocks all of snapshotting will break, so
disable it until I add the snapshot root and drop tree support.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Scrub depends on extent references for every block, and with extent tree
v2 we won't have that, so disable scrub until we can add back the proper
code to handle extent-tree-v2.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Device add, remove, and replace all require balance, which doesn't work
right now on extent tree v2, so disable these for now.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_ioctl extracts inode from file so we can pass that into the
callbacks.
Signed-off-by: Sahil Kang <sahil.kang@asilaycomputing.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_ioctl already contains pointers to the inode and btrfs_root
structs, so we can pass them into the subfunctions instead of the
toplevel struct file.
Signed-off-by: Sahil Kang <sahil.kang@asilaycomputing.com>
Signed-off-by: David Sterba <dsterba@suse.com>
-----BEGIN PGP SIGNATURE-----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=q/NS
-----END PGP SIGNATURE-----
Merge tag 'for-5.17-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"This is a hopefully last batch of fixes for defrag that got broken in
5.16, all stable material.
The remaining reported problem is excessive IO with autodefrag due to
various conditions in the defrag code not met or missing"
* tag 'for-5.17-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: reduce extent threshold for autodefrag
btrfs: autodefrag: only scan one inode once
btrfs: defrag: don't use merged extent map for their generation check
btrfs: defrag: bring back the old file extent search behavior
btrfs: defrag: remove an ambiguous condition for rejection
btrfs: defrag: don't defrag extents which are already at max capacity
btrfs: defrag: don't try to merge regular extents with preallocated extents
btrfs: defrag: allow defrag_one_cluster() to skip large extent which is not a target
btrfs: prevent copying too big compressed lzo segment
For extent maps, if they are not compressed extents and are adjacent by
logical addresses and file offsets, they can be merged into one larger
extent map.
Such merged extent map will have the higher generation of all the
original ones.
But this brings a problem for autodefrag, as it relies on accurate
extent_map::generation to determine if one extent should be defragged.
For merged extent maps, their higher generation can mark some older
extents to be defragged while the original extent map doesn't meet the
minimal generation threshold.
Thus this will cause extra IO.
So solve the problem, here we introduce a new flag, EXTENT_FLAG_MERGED,
to indicate if the extent map is merged from one or more ems.
And for autodefrag, if we find a merged extent map, and its generation
meets the generation requirement, we just don't use this one, and go
back to defrag_get_extent() to read extent maps from subvolume trees.
This could cause more read IO, but should result less defrag data write,
so in the long run it should be a win for autodefrag.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
For defrag, we don't really want to use btrfs_get_extent() to iterate
all extent maps of an inode.
The reasons are:
- btrfs_get_extent() can merge extent maps
And the result em has the higher generation of the two, causing defrag
to mark unnecessary part of such merged large extent map.
This in fact can result extra IO for autodefrag in v5.16+ kernels.
However this patch is not going to completely solve the problem, as
one can still using read() to trigger extent map reading, and got
them merged.
The completely solution for the extent map merging generation problem
will come as an standalone fix.
- btrfs_get_extent() caches the extent map result
Normally it's fine, but for defrag the target range may not get
another read/write for a long long time.
Such cache would only increase the memory usage.
- btrfs_get_extent() doesn't skip older extent map
Unlike the old find_new_extent() which uses btrfs_search_forward() to
skip the older subtree, thus it will pick up unnecessary extent maps.
This patch will fix the regression by introducing defrag_get_extent() to
replace the btrfs_get_extent() call.
This helper will:
- Not cache the file extent we found
It will search the file extent and manually convert it to em.
- Use btrfs_search_forward() to skip entire ranges which is modified in
the past
This should reduce the IO for autodefrag.
Reported-by: Filipe Manana <fdmanana@suse.com>
Fixes: 7b508037d4 ("btrfs: defrag: use defrag_one_cluster() to implement btrfs_defrag_file()")
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
From the very beginning of btrfs defrag, there is a check to reject
extents which meet both conditions:
- Physically adjacent
We may want to defrag physically adjacent extents to reduce the number
of extents or the size of subvolume tree.
- Larger than 128K
This may be there for compressed extents, but unfortunately 128K is
exactly the max capacity for compressed extents.
And the check is > 128K, thus it never rejects compressed extents.
Furthermore, the compressed extent capacity bug is fixed by previous
patch, there is no reason for that check anymore.
The original check has a very small ranges to reject (the target extent
size is > 128K, and default extent threshold is 256K), and for
compressed extent it doesn't work at all.
So it's better just to remove the rejection, and allow us to defrag
physically adjacent extents.
CC: stable@vger.kernel.org # 5.16
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
For compressed extents, defrag ioctl will always try to defrag any
compressed extents, wasting not only IO but also CPU time to
compress/decompress:
mkfs.btrfs -f $DEV
mount -o compress $DEV $MNT
xfs_io -f -c "pwrite -S 0xab 0 128K" $MNT/foobar
sync
xfs_io -f -c "pwrite -S 0xcd 128K 128K" $MNT/foobar
sync
echo "=== before ==="
xfs_io -c "fiemap -v" $MNT/foobar
btrfs filesystem defrag $MNT/foobar
sync
echo "=== after ==="
xfs_io -c "fiemap -v" $MNT/foobar
Then it shows the 2 128K extents just get COW for no extra benefit, with
extra IO/CPU spent:
=== before ===
/mnt/btrfs/file1:
EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS
0: [0..255]: 26624..26879 256 0x8
1: [256..511]: 26632..26887 256 0x9
=== after ===
/mnt/btrfs/file1:
EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS
0: [0..255]: 26640..26895 256 0x8
1: [256..511]: 26648..26903 256 0x9
This affects not only v5.16 (after the defrag rework), but also v5.15
(before the defrag rework).
[CAUSE]
From the very beginning, btrfs defrag never checks if one extent is
already at its max capacity (128K for compressed extents, 128M
otherwise).
And the default extent size threshold is 256K, which is already beyond
the compressed extent max size.
This means, by default btrfs defrag ioctl will mark all compressed
extent which is not adjacent to a hole/preallocated range for defrag.
[FIX]
Introduce a helper to grab the maximum extent size, and then in
defrag_collect_targets() and defrag_check_next_extent(), reject extents
which are already at their max capacity.
Reported-by: Filipe Manana <fdmanana@suse.com>
CC: stable@vger.kernel.org # 5.16
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
With older kernels (before v5.16), btrfs will defrag preallocated extents.
While with newer kernels (v5.16 and newer) btrfs will not defrag
preallocated extents, but it will defrag the extent just before the
preallocated extent, even it's just a single sector.
This can be exposed by the following small script:
mkfs.btrfs -f $dev > /dev/null
mount $dev $mnt
xfs_io -f -c "pwrite 0 4k" -c sync -c "falloc 4k 16K" $mnt/file
xfs_io -c "fiemap -v" $mnt/file
btrfs fi defrag $mnt/file
sync
xfs_io -c "fiemap -v" $mnt/file
The output looks like this on older kernels:
/mnt/btrfs/file:
EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS
0: [0..7]: 26624..26631 8 0x0
1: [8..39]: 26632..26663 32 0x801
/mnt/btrfs/file:
EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS
0: [0..39]: 26664..26703 40 0x1
Which defrags the single sector along with the preallocated extent, and
replace them with an regular extent into a new location (caused by data
COW).
This wastes most of the data IO just for the preallocated range.
On the other hand, v5.16 is slightly better:
/mnt/btrfs/file:
EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS
0: [0..7]: 26624..26631 8 0x0
1: [8..39]: 26632..26663 32 0x801
/mnt/btrfs/file:
EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS
0: [0..7]: 26664..26671 8 0x0
1: [8..39]: 26632..26663 32 0x801
The preallocated range is not defragged, but the sector before it still
gets defragged, which has no need for it.
[CAUSE]
One of the function reused by the old and new behavior is
defrag_check_next_extent(), it will determine if we should defrag
current extent by checking the next one.
It only checks if the next extent is a hole or inlined, but it doesn't
check if it's preallocated.
On the other hand, out of the function, both old and new kernel will
reject preallocated extents.
Such inconsistent behavior causes above behavior.
[FIX]
- Also check if next extent is preallocated
If so, don't defrag current extent.
- Add comments for each branch why we reject the extent
This will reduce the IO caused by defrag ioctl and autodefrag.
CC: stable@vger.kernel.org # 5.16
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In the rework of btrfs_defrag_file(), we always call
defrag_one_cluster() and increase the offset by cluster size, which is
only 256K.
But there are cases where we have a large extent (e.g. 128M) which
doesn't need to be defragged at all.
Before the refactor, we can directly skip the range, but now we have to
scan that extent map again and again until the cluster moves after the
non-target extent.
Fix the problem by allow defrag_one_cluster() to increase
btrfs_defrag_ctrl::last_scanned to the end of an extent, if and only if
the last extent of the cluster is not a target.
The test script looks like this:
mkfs.btrfs -f $dev > /dev/null
mount $dev $mnt
# As btrfs ioctl uses 32M as extent_threshold
xfs_io -f -c "pwrite 0 64M" $mnt/file1
sync
# Some fragemented range to defrag
xfs_io -s -c "pwrite 65548k 4k" \
-c "pwrite 65544k 4k" \
-c "pwrite 65540k 4k" \
-c "pwrite 65536k 4k" \
$mnt/file1
sync
echo "=== before ==="
xfs_io -c "fiemap -v" $mnt/file1
echo "=== after ==="
btrfs fi defrag $mnt/file1
sync
xfs_io -c "fiemap -v" $mnt/file1
umount $mnt
With extra ftrace put into defrag_one_cluster(), before the patch it
would result tons of loops:
(As defrag_one_cluster() is inlined, the function name is its caller)
btrfs-126062 [005] ..... 4682.816026: btrfs_defrag_file: r/i=5/257 start=0 len=262144
btrfs-126062 [005] ..... 4682.816027: btrfs_defrag_file: r/i=5/257 start=262144 len=262144
btrfs-126062 [005] ..... 4682.816028: btrfs_defrag_file: r/i=5/257 start=524288 len=262144
btrfs-126062 [005] ..... 4682.816028: btrfs_defrag_file: r/i=5/257 start=786432 len=262144
btrfs-126062 [005] ..... 4682.816028: btrfs_defrag_file: r/i=5/257 start=1048576 len=262144
...
btrfs-126062 [005] ..... 4682.816043: btrfs_defrag_file: r/i=5/257 start=67108864 len=262144
But with this patch there will be just one loop, then directly to the
end of the extent:
btrfs-130471 [014] ..... 5434.029558: defrag_one_cluster: r/i=5/257 start=0 len=262144
btrfs-130471 [014] ..... 5434.029559: defrag_one_cluster: r/i=5/257 start=67108864 len=16384
CC: stable@vger.kernel.org # 5.16
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
-----BEGIN PGP SIGNATURE-----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=AqU+
-----END PGP SIGNATURE-----
Merge tag 'for-5.17-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
- yield CPU more often when defragmenting a large file
- skip defragmenting extents already under writeback
- improve error message when send fails to write file data
- get rid of warning when mounted with 'flushoncommit'
* tag 'for-5.17-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: send: in case of IO error log it
btrfs: get rid of warning on transaction commit when using flushoncommit
btrfs: defrag: don't try to defrag extents which are under writeback
btrfs: don't hold CPU for too long when defragging a file
Once we start writeback (have called btrfs_run_delalloc_range()), we
allocate an extent, create an extent map point to that extent, with a
generation of (u64)-1, created the ordered extent and then clear the
DELALLOC bit from the range in the inode's io tree.
Such extent map can pass the first call of defrag_collect_targets(), as
its generation is (u64)-1, meets any possible minimal generation check.
And the range will not have DELALLOC bit, also passing the DELALLOC bit
check.
It will only be re-checked in the second call of
defrag_collect_targets(), which will wait for writeback.
But at that stage we have already spent our time waiting for some IO we
may or may not want to defrag.
Let's reject such extents early so we won't waste our time.
CC: stable@vger.kernel.org # 5.16
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There is a user report about "btrfs filesystem defrag" causing 120s
timeout problem.
For btrfs_defrag_file() it will iterate all file extents if called from
defrag ioctl, thus it can take a long time.
There is no reason not to release the CPU during such a long operation.
Add cond_resched() after defragged one cluster.
CC: stable@vger.kernel.org # 5.16
Link: https://lore.kernel.org/linux-btrfs/10e51417-2203-f0a4-2021-86c8511cc367@gmx.com
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
-----BEGIN PGP SIGNATURE-----
iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAmH9eUcACgkQxWXV+ddt
WDvCvQ//bANu7air/Og5r2Mn0ZYyrcQl+yDYE75UC/tzTZNNtP8guwGllwlcsA0v
RQPiuFFtvjKMgKP6Eo1mVeUPkpX83VQkT+sqFRsFEFxazIXnSvEJ+iHVcuiZvgj1
VkTjdt7/mLb573zSA0MLhJqK1BBuFhUTCCHFHlCLoiYeekPAui1pbUC4LAE/+ksU
veCn9YS+NGkDpIv/b9mcALVBe+XkZlmw1LON8ArEbpY4ToafRk0qZfhV7CvyRbSP
Y1zLUScNLHGoR2WA1WhwlwuMePdhgX/8neGNiXsiw3WnmZhFoUVX7oUa6IWnKkKk
dD+x5Z3Z2xBQGK8djyqxzUFJ2VAvz15xGIM452ofGa1BJFZgV9hjPA6Y4RFdWx63
4AZ6OJwhrXhgMtWBhRtM6mGeje56ljwaxku9qhe585z8H5V8ezUNwWVkjY0bLKsd
iT3bUHEReoYRWuyszI1ZSm1DbyzNY2943ly97p/j8qKp4SHX39/QYAKmnuuHdIup
TnTBJOh38rj4S8BfF873aKAo7EfLJcDbTcZ1ivbuX5FeByRuQB4F0c1RRi4usMLc
DL5mhDhT71U1l/LF3IANQ4ieUfZbeFHd+dAVkYsGkYzzaWL8E03L582l/fqaVGsp
RaVpiuKnh2cyDXUxob8IYT5mZ/saa96xBSK8VEqnwjNEQCzKEeU=
=5MJl
-----END PGP SIGNATURE-----
Merge tag 'for-5.17-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"A few fixes and error handling improvements:
- fix deadlock between quota disable and qgroup rescan worker
- fix use-after-free after failure to create a snapshot
- skip warning on unmount after log cleanup failure
- don't start transaction for scrub if the fs is mounted read-only
- tree checker verifies item sizes"
* tag 'for-5.17-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: skip reserved bytes warning on unmount after log cleanup failure
btrfs: fix use of uninitialized variable at rm device ioctl
btrfs: fix use-after-free after failure to create a snapshot
btrfs: tree-checker: check item_size for dev_item
btrfs: tree-checker: check item_size for inode_item
btrfs: fix deadlock between quota disable and qgroup rescan worker
btrfs: don't start transaction for scrub if the fs is mounted read-only
Clang static analysis reports this problem
ioctl.c:3333:8: warning: 3rd function call argument is an
uninitialized value
ret = exclop_start_or_cancel_reloc(fs_info,
cancel is only set in one branch of an if-check and is always used. So
initialize to false.
Fixes: 1a15eb724a ("btrfs: use btrfs_get_dev_args_from_path in dev removal ioctls")
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: David Sterba <dsterba@suse.com>
At ioctl.c:create_snapshot(), we allocate a pending snapshot structure and
then attach it to the transaction's list of pending snapshots. After that
we call btrfs_commit_transaction(), and if that returns an error we jump
to 'fail' label, where we kfree() the pending snapshot structure. This can
result in a later use-after-free of the pending snapshot:
1) We allocated the pending snapshot and added it to the transaction's
list of pending snapshots;
2) We call btrfs_commit_transaction(), and it fails either at the first
call to btrfs_run_delayed_refs() or btrfs_start_dirty_block_groups().
In both cases, we don't abort the transaction and we release our
transaction handle. We jump to the 'fail' label and free the pending
snapshot structure. We return with the pending snapshot still in the
transaction's list;
3) Another task commits the transaction. This time there's no error at
all, and then during the transaction commit it accesses a pointer
to the pending snapshot structure that the snapshot creation task
has already freed, resulting in a user-after-free.
This issue could actually be detected by smatch, which produced the
following warning:
fs/btrfs/ioctl.c:843 create_snapshot() warn: '&pending_snapshot->list' not removed from list
So fix this by not having the snapshot creation ioctl directly add the
pending snapshot to the transaction's list. Instead add the pending
snapshot to the transaction handle, and then at btrfs_commit_transaction()
we add the snapshot to the list only when we can guarantee that any error
returned after that point will result in a transaction abort, in which
case the ioctl code can safely free the pending snapshot and no one can
access it anymore.
CC: stable@vger.kernel.org # 5.10+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
