The ret may be zero in btrfs_search_dir_index_item() and should not
passed to ERR_PTR(). Now btrfs_unlink_subvol() is the only caller to
this, reconstructed it to check ERR_PTR(-ENOENT) while ret >= 0.
This fixes smatch warnings:
fs/btrfs/dir-item.c:353
btrfs_search_dir_index_item() warn: passing zero to 'ERR_PTR'
Fixes: 9dcbe16fcc ("btrfs: use btrfs_for_each_slot in btrfs_search_dir_index_item")
CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
Syzbot reports the following crash:
BTRFS info (device loop0 state MCS): disabling free space tree
BTRFS info (device loop0 state MCS): clearing compat-ro feature flag for FREE_SPACE_TREE (0x1)
BTRFS info (device loop0 state MCS): clearing compat-ro feature flag for FREE_SPACE_TREE_VALID (0x2)
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:backup_super_roots fs/btrfs/disk-io.c:1691 [inline]
RIP: 0010:write_all_supers+0x97a/0x40f0 fs/btrfs/disk-io.c:4041
Call Trace:
<TASK>
btrfs_commit_transaction+0x1eae/0x3740 fs/btrfs/transaction.c:2530
btrfs_delete_free_space_tree+0x383/0x730 fs/btrfs/free-space-tree.c:1312
btrfs_start_pre_rw_mount+0xf28/0x1300 fs/btrfs/disk-io.c:3012
btrfs_remount_rw fs/btrfs/super.c:1309 [inline]
btrfs_reconfigure+0xae6/0x2d40 fs/btrfs/super.c:1534
btrfs_reconfigure_for_mount fs/btrfs/super.c:2020 [inline]
btrfs_get_tree_subvol fs/btrfs/super.c:2079 [inline]
btrfs_get_tree+0x918/0x1920 fs/btrfs/super.c:2115
vfs_get_tree+0x90/0x2b0 fs/super.c:1800
do_new_mount+0x2be/0xb40 fs/namespace.c:3472
do_mount fs/namespace.c:3812 [inline]
__do_sys_mount fs/namespace.c:4020 [inline]
__se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3997
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
[CAUSE]
To support mounting different subvolume with different RO/RW flags for
the new mount APIs, btrfs introduced two workaround to support this feature:
- Skip mount option/feature checks if we are mounting a different
subvolume
- Reconfigure the fs to RW if the initial mount is RO
Combining these two, we can have the following sequence:
- Mount the fs ro,rescue=all,clear_cache,space_cache=v1
rescue=all will mark the fs as hard read-only, so no v2 cache clearing
will happen.
- Mount a subvolume rw of the same fs.
We go into btrfs_get_tree_subvol(), but fc_mount() returns EBUSY
because our new fc is RW, different from the original fs.
Now we enter btrfs_reconfigure_for_mount(), which switches the RO flag
first so that we can grab the existing fs_info.
Then we reconfigure the fs to RW.
- During reconfiguration, option/features check is skipped
This means we will restart the v2 cache clearing, and convert back to
v1 cache.
This will trigger fs writes, and since the original fs has "rescue=all"
option, it skips the csum tree read.
And eventually causing NULL pointer dereference in super block
writeback.
[FIX]
For reconfiguration caused by different subvolume RO/RW flags, ensure we
always run btrfs_check_options() to ensure we have proper hard RO
requirements met.
In fact the function btrfs_check_options() doesn't really do many
complex checks, but hard RO requirement and some feature dependency
checks, thus there is no special reason not to do the check for mount
reconfiguration.
Reported-by: syzbot+56360f93efa90ff15870@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/0000000000008c5d090621cb2770@google.com/
Fixes: f044b31867 ("btrfs: handle the ro->rw transition for mounting different subvolumes")
CC: stable@vger.kernel.org # 6.8+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In debugging some corrupt squashfs files, we observed symptoms of
corrupt page cache pages but correct on-disk contents. Further
investigation revealed that the exact symptom was a correct page
followed by an incorrect, duplicate, page. This got us thinking about
extent maps.
commit ac05ca913e ("Btrfs: fix race between using extent maps and merging them")
enforces a reference count on the primary `em` extent_map being merged,
as that one gets modified.
However, since,
commit 3d2ac99224 ("btrfs: introduce new members for extent_map")
both 'em' and 'merge' get modified, which started modifying 'merge'
and thus introduced the same race.
We were able to reproduce this by looping the affected squashfs workload
in parallel on a bunch of separate btrfs-es while also dropping caches.
We are still working on a simple enough reproducer to make into an fstest.
The simplest fix is to stop modifying 'merge', which is not essential,
as it is dropped immediately after the merge. This behavior is simply
a consequence of the order of the two extent maps being important in
computing the new values. Modify merge_ondisk_extents to take prev and
next by const* and also take a third merged parameter that it puts the
results in. Note that this introduces the rather odd behavior of passing
'em' to merge_ondisk_extents as a const * and as a regular ptr.
Fixes: 3d2ac99224 ("btrfs: introduce new members for extent_map")
CC: stable@vger.kernel.org # 6.11+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
Inside lock_delalloc_folios(), there are several problems related to
sector size < page size handling:
- Set the writer locks without checking if the folio is still valid
We call btrfs_folio_start_writer_lock() just like it's folio_lock().
But since the folio may not even be the folio of the current mapping,
we can easily screw up the folio->private.
- The range is not clamped inside the page
This means we can over write other bitmaps if the start/len is not
properly handled, and trigger the btrfs_subpage_assert().
- @processed_end is always rounded up to page end
If the delalloc range is not page aligned, and we need to retry
(returning -EAGAIN), then we will unlock to the page end.
Thankfully this is not a huge problem, as now
btrfs_folio_end_writer_lock() can handle range larger than the locked
range, and only unlock what is already locked.
Fix all these problems by:
- Lock and check the folio first, then call
btrfs_folio_set_writer_lock()
So that if we got a folio not belonging to the inode, we won't
touch folio->private.
- Properly truncate the range inside the page
- Update @processed_end to the locked range end
Fixes: 1e1de38792 ("btrfs: make process_one_page() to handle subpage locking")
CC: stable@vger.kernel.org # 6.1+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since commit 011b46c304 ("btrfs: skip subtree scan if it's too high to
avoid low stall in btrfs_commit_transaction()"), btrfs qgroup can
automatically skip large subtree scan at the cost of marking qgroup
inconsistent.
It's designed to address the final performance problem of snapshot drop
with qgroup enabled, but to be safe the default value is
BTRFS_MAX_LEVEL, requiring a user space daemon to set a different value
to make it work.
I'd say it's not a good idea to rely on user space tool to set this
default value, especially when some operations (snapshot dropping) can
be triggered immediately after mount, leaving a very small window to
that that sysfs interface.
So instead of disabling this new feature by default, enable it with a
low threshold (3), so that large subvolume tree drop at mount time won't
cause huge qgroup workload.
CC: stable@vger.kernel.org # 6.1
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
After the migration to use fs context for processing mount options we had
a slight change in the semantics for remounting a filesystem that was
mounted with compress-force. Before we could clear compress-force by
passing only "-o compress[=algo]" during a remount, but after that change
that does not work anymore, force-compress is still present and one needs
to pass "-o compress-force=no,compress[=algo]" to the mount command.
Example, when running on a kernel 6.8+:
$ mount -o compress-force=zlib:9 /dev/sdi /mnt/sdi
$ mount | grep sdi
/dev/sdi on /mnt/sdi type btrfs (rw,relatime,compress-force=zlib:9,discard=async,space_cache=v2,subvolid=5,subvol=/)
$ mount -o remount,compress=zlib:5 /mnt/sdi
$ mount | grep sdi
/dev/sdi on /mnt/sdi type btrfs (rw,relatime,compress-force=zlib:5,discard=async,space_cache=v2,subvolid=5,subvol=/)
On a 6.7 kernel (or older):
$ mount -o compress-force=zlib:9 /dev/sdi /mnt/sdi
$ mount | grep sdi
/dev/sdi on /mnt/sdi type btrfs (rw,relatime,compress-force=zlib:9,discard=async,space_cache=v2,subvolid=5,subvol=/)
$ mount -o remount,compress=zlib:5 /mnt/sdi
$ mount | grep sdi
/dev/sdi on /mnt/sdi type btrfs (rw,relatime,compress=zlib:5,discard=async,space_cache=v2,subvolid=5,subvol=/)
So update btrfs_parse_param() to clear "compress-force" when "compress" is
given, providing the same semantics as kernel 6.7 and older.
Reported-by: Roman Mamedov <rm@romanrm.net>
Link: https://lore.kernel.org/linux-btrfs/20241014182416.13d0f8b0@nvm/
CC: stable@vger.kernel.org # 6.8+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When btrfs reserves an extent and does not use it (e.g, by an error), it
calls btrfs_free_reserved_extent() to free the reserved extent. In the
process, it calls btrfs_add_free_space() and then it accounts the region
bytes as block_group->zone_unusable.
However, it leaves the space_info->bytes_zone_unusable side not updated. As
a result, ENOSPC can happen while a space_info reservation succeeded. The
reservation is fine because the freed region is not added in
space_info->bytes_zone_unusable, leaving that space as "free". OTOH,
corresponding block group counts it as zone_unusable and its allocation
pointer is not rewound, we cannot allocate an extent from that block group.
That will also negate space_info's async/sync reclaim process, and cause an
ENOSPC error from the extent allocation process.
Fix that by returning the space to space_info->bytes_zone_unusable.
Ideally, since a bio is not submitted for this reserved region, we should
return the space to free space and rewind the allocation pointer. But, it
needs rework on extent allocation handling, so let it work in this way for
now.
Fixes: 169e0da91a ("btrfs: zoned: track unusable bytes for zones")
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Merge tag 'for-6.12-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
- regression fix: dirty extents tracked in xarray for qgroups must be
adjusted for 32bit platforms
- fix potentially freeing uninitialized name in fscrypt structure
- fix warning about unneeded variable in a send callback
* tag 'for-6.12-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: fix uninitialized pointer free on read_alloc_one_name() error
btrfs: send: cleanup unneeded return variable in changed_verity()
btrfs: fix uninitialized pointer free in add_inode_ref()
btrfs: use sector numbers as keys for the dirty extents xarray
The function read_alloc_one_name() does not initialize the name field of
the passed fscrypt_str struct if kmalloc fails to allocate the
corresponding buffer. Thus, it is not guaranteed that
fscrypt_str.name is initialized when freeing it.
This is a follow-up to the linked patch that fixes the remaining
instances of the bug introduced by commit e43eec81c5 ("btrfs: use
struct qstr instead of name and namelen pairs").
Link: https://lore.kernel.org/linux-btrfs/20241009080833.1355894-1-jroi.martin@gmail.com/
Fixes: e43eec81c5 ("btrfs: use struct qstr instead of name and namelen pairs")
CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Roi Martin <jroi.martin@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
As all changed_* functions need to return something, just return 0
directly here, as the verity status is passed via the context.
Reported by LKP: fs/btrfs/send.c:6877:5-8: Unneeded variable: "ret". Return "0" on line 6883
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/oe-kbuild-all/202410092305.WbyqspH8-lkp@intel.com/
Signed-off-by: Christian Heusel <christian@heusel.eu>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The add_inode_ref() function does not initialize the "name" struct when
it is declared. If any of the following calls to "read_one_inode()
returns NULL,
dir = read_one_inode(root, parent_objectid);
if (!dir) {
ret = -ENOENT;
goto out;
}
inode = read_one_inode(root, inode_objectid);
if (!inode) {
ret = -EIO;
goto out;
}
then "name.name" would be freed on "out" before being initialized.
out:
...
kfree(name.name);
This issue was reported by Coverity with CID 1526744.
Fixes: e43eec81c5 ("btrfs: use struct qstr instead of name and namelen pairs")
CC: stable@vger.kernel.org # 6.6+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Roi Martin <jroi.martin@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We are using the logical address ("bytenr") of an extent as the key for
qgroup records in the dirty extents xarray. This is a problem because the
xarrays use "unsigned long" for keys/indices, meaning that on a 32 bits
platform any extent starting at or beyond 4G is truncated, which is a too
low limitation as virtually everyone is using storage with more than 4G of
space. This means a "bytenr" of 4G gets truncated to 0, and so does 8G and
16G for example, resulting in incorrect qgroup accounting.
Fix this by using sector numbers as keys instead, that is, using keys that
match the logical address right shifted by fs_info->sectorsize_bits, which
is what we do for the fs_info->buffer_radix that tracks extent buffers
(radix trees also use an "unsigned long" type for keys). This also makes
the index space more dense which helps optimize the xarray (as mentioned
at Documentation/core-api/xarray.rst).
Fixes: 3cce39a8ca ("btrfs: qgroup: use xarray to track dirty extents in transaction")
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Merge tag 'for-6.12-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
- update fstrim loop and add more cancellation points, fix reported
delayed or blocked suspend if there's a huge chunk queued
- fix error handling in recent qgroup xarray conversion
- in zoned mode, fix warning printing device path without RCU
protection
- again fix invalid extent xarray state (6252690f7e), lost due to
refactoring
* tag 'for-6.12-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: fix clear_dirty and writeback ordering in submit_one_sector()
btrfs: zoned: fix missing RCU locking in error message when loading zone info
btrfs: fix missing error handling when adding delayed ref with qgroups enabled
btrfs: add cancellation points to trim loops
btrfs: split remaining space to discard in chunks
Jeff Layton <jlayton@kernel.org> says:
The VFS has always used coarse-grained timestamps when updating the
ctime and mtime after a change. This has the benefit of allowing
filesystems to optimize away a lot metadata updates, down to around 1
per jiffy, even when a file is under heavy writes.
Unfortunately, this has always been an issue when we're exporting via
NFSv3, which relies on timestamps to validate caches. A lot of changes
can happen in a jiffy, so timestamps aren't sufficient to help the
client decide when to invalidate the cache. Even with NFSv4, a lot of
exported filesystems don't properly support a change attribute and are
subject to the same problems with timestamp granularity. Other
applications have similar issues with timestamps (e.g backup
applications).
If we were to always use fine-grained timestamps, that would improve the
situation, but that becomes rather expensive, as the underlying
filesystem would have to log a lot more metadata updates.
What we need is a way to only use fine-grained timestamps when they are
being actively queried. Use the (unused) top bit in inode->i_ctime_nsec
as a flag that indicates whether the current timestamps have been
queried via stat() or the like. When it's set, we allow the kernel to
use a fine-grained timestamp iff it's necessary to make the ctime show
a different value.
This solves the problem of being able to distinguish the timestamp
between updates, but introduces a new problem: it's now possible for a
file being changed to get a fine-grained timestamp. A file that is
altered just a bit later can then get a coarse-grained one that appears
older than the earlier fine-grained time. This violates timestamp
ordering guarantees.
To remedy this, keep a global monotonic atomic64_t value that acts as a
timestamp floor. When we go to stamp a file, we first get the latter of
the current floor value and the current coarse-grained time. If the
inode ctime hasn't been queried then we just attempt to stamp it with
that value.
If it has been queried, then first see whether the current coarse time
is later than the existing ctime. If it is, then we accept that value.
If it isn't, then we get a fine-grained time and try to swap that into
the global floor. Whether that succeeds or fails, we take the resulting
floor time, convert it to realtime and try to swap that into the ctime.
We take the result of the ctime swap whether it succeeds or fails, since
either is just as valid.
Filesystems can opt into this by setting the FS_MGTIME fstype flag.
Others should be unaffected (other than being subject to the same floor
value as multigrain filesystems).
* patches from https://lore.kernel.org/r/20241002-mgtime-v10-0-d1c4717f5284@kernel.org:
tmpfs: add support for multigrain timestamps
btrfs: convert to multigrain timestamps
ext4: switch to multigrain timestamps
xfs: switch to multigrain timestamps
Documentation: add a new file documenting multigrain timestamps
fs: add percpu counters for significant multigrain timestamp events
fs: tracepoints around multigrain timestamp events
fs: handle delegated timestamps in setattr_copy_mgtime
fs: have setattr_copy handle multigrain timestamps appropriately
fs: add infrastructure for multigrain timestamps
Link: https://lore.kernel.org/r/20241002-mgtime-v10-0-d1c4717f5284@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
Enable multigrain timestamps, which should ensure that there is an
apparent change to the timestamp whenever it has been written after
being actively observed via getattr.
Beyond enabling the FS_MGTIME flag, this patch eliminates
update_time_for_write, which goes to great pains to avoid in-memory
stores. Just have it overwrite the timestamps unconditionally.
Note that this also drops the IS_I_VERSION check and unconditionally
bumps the change attribute, since SB_I_VERSION is always set on btrfs.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Tested-by: Randy Dunlap <rdunlap@infradead.org> # documentation bits
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20241002-mgtime-v10-11-d1c4717f5284@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
This commit is a replay of commit 6252690f7e ("btrfs: fix invalid
mapping of extent xarray state"). We need to call
btrfs_folio_clear_dirty() before btrfs_set_range_writeback(), so that
xarray DIRTY tag is cleared.
With a refactoring commit 8189197425 ("btrfs: refactor
__extent_writepage_io() to do sector-by-sector submission"), it screwed
up and the order is reversed and causing the same hang. Fix the ordering
now in submit_one_sector().
Fixes: 8189197425 ("btrfs: refactor __extent_writepage_io() to do sector-by-sector submission")
Reviewed-by: Qu Wenruo <wqu@suse.com>
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>
At btrfs_load_zone_info() we have an error path that is dereferencing
the name of a device which is a RCU string but we are not holding a RCU
read lock, which is incorrect.
Fix this by using btrfs_err_in_rcu() instead of btrfs_err().
The problem is there since commit 08e11a3db0 ("btrfs: zoned: load zone's
allocation offset"), back then at btrfs_load_block_group_zone_info() but
then later on that code was factored out into the helper
btrfs_load_zone_info() by commit 09a46725cc ("btrfs: zoned: factor out
per-zone logic from btrfs_load_block_group_zone_info").
Fixes: 08e11a3db0 ("btrfs: zoned: load zone's allocation offset")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When adding a delayed ref head, at delayed-ref.c:add_delayed_ref_head(),
if we fail to insert the qgroup record we don't error out, we ignore it.
In fact we treat it as if there was no error and there was already an
existing record - we don't distinguish between the cases where
btrfs_qgroup_trace_extent_nolock() returns 1, meaning a record already
existed and we can free the given record, and the case where it returns
a negative error value, meaning the insertion into the xarray that is
used to track records failed.
Effectively we end up ignoring that we are lacking qgroup record in the
dirty extents xarray, resulting in incorrect qgroup accounting.
Fix this by checking for errors and return them to the callers.
Fixes: 3cce39a8ca ("btrfs: qgroup: use xarray to track dirty extents in transaction")
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are reports that system cannot suspend due to running trim because
the task responsible for trimming the device isn't able to finish in
time, especially since we have a free extent discarding phase, which can
trim a lot of unallocated space. There are no limits on the trim size
(unlike the block group part).
Since trime isn't a critical call it can be interrupted at any time,
in such cases we stop the trim, report the amount of discarded bytes and
return an error.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=219180
Link: https://bugzilla.suse.com/show_bug.cgi?id=1229737
CC: stable@vger.kernel.org # 5.15+
Signed-off-by: Luca Stefani <luca.stefani.ge1@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Per Qu Wenruo in case we have a very large disk, e.g. 8TiB device,
mostly empty although we will do the split according to our super block
locations, the last super block ends at 256G, we can submit a huge
discard for the range [256G, 8T), causing a large delay.
Split the space left to discard based on BTRFS_MAX_DISCARD_CHUNK_SIZE in
preparation of introduction of cancellation points to trim. The value
of the chunk size is arbitrary, it can be higher or derived from actual
device capabilities but we can't easily read that using
bio_discard_limit().
Link: https://bugzilla.kernel.org/show_bug.cgi?id=219180
Link: https://bugzilla.suse.com/show_bug.cgi?id=1229737
CC: stable@vger.kernel.org # 5.15+
Signed-off-by: Luca Stefani <luca.stefani.ge1@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Merge tag 'for-6.12-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
- in incremental send, fix invalid clone operation for file that got
its size decreased
- fix __counted_by() annotation of send path cache entries, we do not
store the terminating NUL
- fix a longstanding bug in relocation (and quite hard to hit by
chance), drop back reference cache that can get out of sync after
transaction commit
- wait for fixup worker kthread before finishing umount
- add missing raid-stripe-tree extent for NOCOW files, zoned mode
cannot have NOCOW files but RST is meant to be a standalone feature
- handle transaction start error during relocation, avoid potential
NULL pointer dereference of relocation control structure (reported by
syzbot)
- disable module-wide rate limiting of debug level messages
- minor fix to tracepoint definition (reported by checkpatch.pl)
* tag 'for-6.12-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: disable rate limiting when debug enabled
btrfs: wait for fixup workers before stopping cleaner kthread during umount
btrfs: fix a NULL pointer dereference when failed to start a new trasacntion
btrfs: send: fix invalid clone operation for file that got its size decreased
btrfs: tracepoints: end assignment with semicolon at btrfs_qgroup_extent event class
btrfs: drop the backref cache during relocation if we commit
btrfs: also add stripe entries for NOCOW writes
btrfs: send: fix buffer overflow detection when copying path to cache entry
We are close to removing the private_2 flag, so switch btrfs to using
owner_2 for its ordered flag. This is mostly used by buffer head
filesystems, so btrfs can use it because it doesn't use buffer heads.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Link: https://lore.kernel.org/r/20241002040111.1023018-5-willy@infradead.org
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
asm/unaligned.h is always an include of asm-generic/unaligned.h;
might as well move that thing to linux/unaligned.h and include
that - there's nothing arch-specific in that header.
auto-generated by the following:
for i in `git grep -l -w asm/unaligned.h`; do
sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i
done
for i in `git grep -l -w asm-generic/unaligned.h`; do
sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i
done
git mv include/asm-generic/unaligned.h include/linux/unaligned.h
git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h
sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild
sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
Disable ratelimiting for btrfs_printk when CONFIG_BTRFS_DEBUG is
enabled. This allows for more verbose output which is often needed by
functions like btrfs_dump_space_info().
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Leo Martins <loemra.dev@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
Syzbot reported a NULL pointer dereference with the following crash:
FAULT_INJECTION: forcing a failure.
start_transaction+0x830/0x1670 fs/btrfs/transaction.c:676
prepare_to_relocate+0x31f/0x4c0 fs/btrfs/relocation.c:3642
relocate_block_group+0x169/0xd20 fs/btrfs/relocation.c:3678
...
BTRFS info (device loop0): balance: ended with status: -12
Oops: general protection fault, probably for non-canonical address 0xdffffc00000000cc: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000660-0x0000000000000667]
RIP: 0010:btrfs_update_reloc_root+0x362/0xa80 fs/btrfs/relocation.c:926
Call Trace:
<TASK>
commit_fs_roots+0x2ee/0x720 fs/btrfs/transaction.c:1496
btrfs_commit_transaction+0xfaf/0x3740 fs/btrfs/transaction.c:2430
del_balance_item fs/btrfs/volumes.c:3678 [inline]
reset_balance_state+0x25e/0x3c0 fs/btrfs/volumes.c:3742
btrfs_balance+0xead/0x10c0 fs/btrfs/volumes.c:4574
btrfs_ioctl_balance+0x493/0x7c0 fs/btrfs/ioctl.c:3673
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:907 [inline]
__se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
[CAUSE]
The allocation failure happens at the start_transaction() inside
prepare_to_relocate(), and during the error handling we call
unset_reloc_control(), which makes fs_info->balance_ctl to be NULL.
Then we continue the error path cleanup in btrfs_balance() by calling
reset_balance_state() which will call del_balance_item() to fully delete
the balance item in the root tree.
However during the small window between set_reloc_contrl() and
unset_reloc_control(), we can have a subvolume tree update and created a
reloc_root for that subvolume.
Then we go into the final btrfs_commit_transaction() of
del_balance_item(), and into btrfs_update_reloc_root() inside
commit_fs_roots().
That function checks if fs_info->reloc_ctl is in the merge_reloc_tree
stage, but since fs_info->reloc_ctl is NULL, it results a NULL pointer
dereference.
[FIX]
Just add extra check on fs_info->reloc_ctl inside
btrfs_update_reloc_root(), before checking
fs_info->reloc_ctl->merge_reloc_tree.
That DEAD_RELOC_TREE handling is to prevent further modification to the
reloc tree during merge stage, but since there is no reloc_ctl at all,
we do not need to bother that.
Reported-by: syzbot+283673dbc38527ef9f3d@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/66f6bfa7.050a0220.38ace9.0019.GAE@google.com/
CC: stable@vger.kernel.org # 4.19+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
During an incremental send we may end up sending an invalid clone
operation, for the last extent of a file which ends at an unaligned offset
that matches the final i_size of the file in the send snapshot, in case
the file had its initial size (the size in the parent snapshot) decreased
in the send snapshot. In this case the destination will fail to apply the
clone operation because its end offset is not sector size aligned and it
ends before the current size of the file.
Sending the truncate operation always happens when we finish processing an
inode, after we process all its extents (and xattrs, names, etc). So fix
this by ensuring the file has a valid size before we send a clone
operation for an unaligned extent that ends at the final i_size of the
file. The size we truncate to matches the start offset of the clone range
but it could be any value between that start offset and the final size of
the file since the clone operation will expand the i_size if the current
size is smaller than the end offset. The start offset of the range was
chosen because it's always sector size aligned and avoids a truncation
into the middle of a page, which results in dirtying the page due to
filling part of it with zeroes and then making the clone operation at the
receiver trigger IO.
The following test reproduces the issue:
$ cat test.sh
#!/bin/bash
DEV=/dev/sdi
MNT=/mnt/sdi
mkfs.btrfs -f $DEV
mount $DEV $MNT
# Create a file with a size of 256K + 5 bytes, having two extents, one
# with a size of 128K and another one with a size of 128K + 5 bytes.
last_ext_size=$((128 * 1024 + 5))
xfs_io -f -d -c "pwrite -S 0xab -b 128K 0 128K" \
-c "pwrite -S 0xcd -b $last_ext_size 128K $last_ext_size" \
$MNT/foo
# Another file which we will later clone foo into, but initially with
# a larger size than foo.
xfs_io -f -c "pwrite -S 0xef 0 1M" $MNT/bar
btrfs subvolume snapshot -r $MNT/ $MNT/snap1
# Now resize bar and clone foo into it.
xfs_io -c "truncate 0" \
-c "reflink $MNT/foo" $MNT/bar
btrfs subvolume snapshot -r $MNT/ $MNT/snap2
rm -f /tmp/send-full /tmp/send-inc
btrfs send -f /tmp/send-full $MNT/snap1
btrfs send -p $MNT/snap1 -f /tmp/send-inc $MNT/snap2
umount $MNT
mkfs.btrfs -f $DEV
mount $DEV $MNT
btrfs receive -f /tmp/send-full $MNT
btrfs receive -f /tmp/send-inc $MNT
umount $MNT
Running it before this patch:
$ ./test.sh
(...)
At subvol snap1
At snapshot snap2
ERROR: failed to clone extents to bar: Invalid argument
A test case for fstests will be sent soon.
Reported-by: Ben Millwood <thebenmachine@gmail.com>
Link: https://lore.kernel.org/linux-btrfs/CAJhrHS2z+WViO2h=ojYvBPDLsATwLbg+7JaNCyYomv0fUxEpQQ@mail.gmail.com/
Fixes: 46a6e10a1a ("btrfs: send: allow cloning non-aligned extent if it ends at i_size")
CC: stable@vger.kernel.org # 6.11
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since the inception of relocation we have maintained the backref cache
across transaction commits, updating the backref cache with the new
bytenr whenever we COWed blocks that were in the cache, and then
updating their bytenr once we detected a transaction id change.
This works as long as we're only ever modifying blocks, not changing the
structure of the tree.
However relocation does in fact change the structure of the tree. For
example, if we are relocating a data extent, we will look up all the
leaves that point to this data extent. We will then call
do_relocation() on each of these leaves, which will COW down to the leaf
and then update the file extent location.
But, a key feature of do_relocation() is the pending list. This is all
the pending nodes that we modified when we updated the file extent item.
We will then process all of these blocks via finish_pending_nodes, which
calls do_relocation() on all of the nodes that led up to that leaf.
The purpose of this is to make sure we don't break sharing unless we
absolutely have to. Consider the case that we have 3 snapshots that all
point to this leaf through the same nodes, the initial COW would have
created a whole new path. If we did this for all 3 snapshots we would
end up with 3x the number of nodes we had originally. To avoid this we
will cycle through each of the snapshots that point to each of these
nodes and update their pointers to point at the new nodes.
Once we update the pointer to the new node we will drop the node we
removed the link for and all of its children via btrfs_drop_subtree().
This is essentially just btrfs_drop_snapshot(), but for an arbitrary
point in the snapshot.
The problem with this is that we will never reflect this in the backref
cache. If we do this btrfs_drop_snapshot() for a node that is in the
backref tree, we will leave the node in the backref tree. This becomes
a problem when we change the transid, as now the backref cache has
entire subtrees that no longer exist, but exist as if they still are
pointed to by the same roots.
In the best case scenario you end up with "adding refs to an existing
tree ref" errors from insert_inline_extent_backref(), where we attempt
to link in nodes on roots that are no longer valid.
Worst case you will double free some random block and re-use it when
there's still references to the block.
This is extremely subtle, and the consequences are quite bad. There
isn't a way to make sure our backref cache is consistent between
transid's.
In order to fix this we need to simply evict the entire backref cache
anytime we cross transid's. This reduces performance in that we have to
rebuild this backref cache every time we change transid's, but fixes the
bug.
This has existed since relocation was added, and is a pretty critical
bug. There's a lot more cleanup that can be done now that this
functionality is going away, but this patch is as small as possible in
order to fix the problem and make it easy for us to backport it to all
the kernels it needs to be backported to.
Followup series will dismantle more of this code and simplify relocation
drastically to remove this functionality.
We have a reproducer that reproduced the corruption within a few minutes
of running. With this patch it survives several iterations/hours of
running the reproducer.
Fixes: 3fd0a5585e ("Btrfs: Metadata ENOSPC handling for balance")
CC: stable@vger.kernel.org
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
NOCOW writes do not generate stripe_extent entries in the RAID stripe
tree, as the RAID stripe-tree feature initially was designed with a
zoned filesystem in mind and on a zoned filesystem, we do not allow NOCOW
writes. But the RAID stripe-tree feature is independent from the zoned
feature, so we must also do NOCOW writes for RAID stripe-tree filesystems.
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Merge tag 'for-6.12-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
- fix dangling pointer to rb-tree of defragmented inodes after cleanup
- a followup fix to handle concurrent lseek on the same fd that could
leak memory under some conditions
- fix wrong root id reported in tree checker when verifying dref
* tag 'for-6.12-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: fix use-after-free on rbtree that tracks inodes for auto defrag
btrfs: tree-checker: fix the wrong output of data backref objectid
btrfs: fix race setting file private on concurrent lseek using same fd
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Merge tag 'pull-stable-struct_fd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull 'struct fd' updates from Al Viro:
"Just the 'struct fd' layout change, with conversion to accessor
helpers"
* tag 'pull-stable-struct_fd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
add struct fd constructors, get rid of __to_fd()
struct fd: representation change
introduce fd_file(), convert all accessors to it.
When cleaning up defrag inodes at btrfs_cleanup_defrag_inodes(), called
during remount and unmount, we are freeing every node from the rbtree
that tracks inodes for auto defrag using
rbtree_postorder_for_each_entry_safe(), which doesn't modify the tree
itself. So once we unlock the lock that protects the rbtree, we have a
tree pointing to a root that was freed (and a root pointing to freed
nodes, and their children pointing to other freed nodes, and so on).
This makes further access to the tree result in a use-after-free with
unpredictable results.
Fix this by initializing the rbtree to an empty root after the call to
rbtree_postorder_for_each_entry_safe() and before unlocking.
Fixes: 276940915f ("btrfs: clear defragmented inodes using postorder in btrfs_cleanup_defrag_inodes()")
Reported-by: syzbot+ad7966ca1f5dd8b001b3@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/000000000000f9aad406223eabff@google.com/
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
There are some reports about invalid data backref objectids, the report
looks like this:
BTRFS critical (device sda): corrupt leaf: block=333654787489792 slot=110 extent bytenr=333413935558656 len=65536 invalid data ref objectid value 2543
The data ref objectid is the inode number inside the subvolume.
But in above case, the value is completely sane, not really showing the
problem.
[CAUSE]
The root cause of the problem is the deprecated feature, inode cache.
This feature results a special inode number, -12ULL, and it's no longer
recognized by tree-checker, triggering the error.
The direct problem here is the output of data ref objectid. The value
shown is in fact the dref_root (subvolume id), not the dref_objectid
(inode number).
[FIX]
Fix the output to use dref_objectid instead.
Reported-by: Neil Parton <njparton@gmail.com>
Reported-by: Archange <archange@archlinux.org>
Link: https://lore.kernel.org/linux-btrfs/CAAYHqBbrrgmh6UmW3ANbysJX9qG9Pbg3ZwnKsV=5mOpv_qix_Q@mail.gmail.com/
Link: https://lore.kernel.org/linux-btrfs/9541deea-9056-406e-be16-a996b549614d@archlinux.org/
Fixes: f333a3c7e8 ("btrfs: tree-checker: validate dref root and objectid")
CC: stable@vger.kernel.org # 6.11
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>
When doing concurrent lseek(2) system calls against the same file
descriptor, using multiple threads belonging to the same process, we have
a short time window where a race happens and can result in a memory leak.
The race happens like this:
1) A program opens a file descriptor for a file and then spawns two
threads (with the pthreads library for example), lets call them
task A and task B;
2) Task A calls lseek with SEEK_DATA or SEEK_HOLE and ends up at
file.c:find_desired_extent() while holding a read lock on the inode;
3) At the start of find_desired_extent(), it extracts the file's
private_data pointer into a local variable named 'private', which has
a value of NULL;
4) Task B also calls lseek with SEEK_DATA or SEEK_HOLE, locks the inode
in shared mode and enters file.c:find_desired_extent(), where it also
extracts file->private_data into its local variable 'private', which
has a NULL value;
5) Because it saw a NULL file private, task A allocates a private
structure and assigns to the file structure;
6) Task B also saw a NULL file private so it also allocates its own file
private and then assigns it to the same file structure, since both
tasks are using the same file descriptor.
At this point we leak the private structure allocated by task A.
Besides the memory leak, there's also the detail that both tasks end up
using the same cached state record in the private structure (struct
btrfs_file_private::llseek_cached_state), which can result in a
use-after-free problem since one task can free it while the other is
still using it (only one task took a reference count on it). Also, sharing
the cached state is not a good idea since it could result in incorrect
results in the future - right now it should not be a problem because it
end ups being used only in extent-io-tree.c:count_range_bits() where we do
range validation before using the cached state.
Fix this by protecting the private assignment and check of a file while
holding the inode's spinlock and keep track of the task that allocated
the private, so that it's used only by that task in order to prevent
user-after-free issues with the cached state record as well as potentially
using it incorrectly in the future.
Fixes: 3c32c7212f ("btrfs: use cached state when looking for delalloc ranges with lseek")
CC: stable@vger.kernel.org # 6.6+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Merge tag 'for-6.12/block-20240913' of git://git.kernel.dk/linux
Pull block updates from Jens Axboe:
- MD changes via Song:
- md-bitmap refactoring (Yu Kuai)
- raid5 performance optimization (Artur Paszkiewicz)
- Other small fixes (Yu Kuai, Chen Ni)
- Add a sysfs entry 'new_level' (Xiao Ni)
- Improve information reported in /proc/mdstat (Mateusz Kusiak)
- NVMe changes via Keith:
- Asynchronous namespace scanning (Stuart)
- TCP TLS updates (Hannes)
- RDMA queue controller validation (Niklas)
- Align field names to the spec (Anuj)
- Metadata support validation (Puranjay)
- A syntax cleanup (Shen)
- Fix a Kconfig linking error (Arnd)
- New queue-depth quirk (Keith)
- Add missing unplug trace event (Keith)
- blk-iocost fixes (Colin, Konstantin)
- t10-pi modular removal and fixes (Alexey)
- Fix for potential BLKSECDISCARD overflow (Alexey)
- bio splitting cleanups and fixes (Christoph)
- Deal with folios rather than rather than pages, speeding up how the
block layer handles bigger IOs (Kundan)
- Use spinlocks rather than bit spinlocks in zram (Sebastian, Mike)
- Reduce zoned device overhead in ublk (Ming)
- Add and use sendpages_ok() for drbd and nvme-tcp (Ofir)
- Fix regression in partition error pointer checking (Riyan)
- Add support for write zeroes and rotational status in nbd (Wouter)
- Add Yu Kuai as new BFQ maintainer. The scheduler has been
unmaintained for quite a while.
- Various sets of fixes for BFQ (Yu Kuai)
- Misc fixes and cleanups (Alvaro, Christophe, Li, Md Haris, Mikhail,
Yang)
* tag 'for-6.12/block-20240913' of git://git.kernel.dk/linux: (120 commits)
nvme-pci: qdepth 1 quirk
block: fix potential invalid pointer dereference in blk_add_partition
blk_iocost: make read-only static array vrate_adj_pct const
block: unpin user pages belonging to a folio at once
mm: release number of pages of a folio
block: introduce folio awareness and add a bigger size from folio
block: Added folio-ized version of bio_add_hw_page()
block, bfq: factor out a helper to split bfqq in bfq_init_rq()
block, bfq: remove local variable 'bfqq_already_existing' in bfq_init_rq()
block, bfq: remove local variable 'split' in bfq_init_rq()
block, bfq: remove bfq_log_bfqg()
block, bfq: merge bfq_release_process_ref() into bfq_put_cooperator()
block, bfq: fix procress reference leakage for bfqq in merge chain
block, bfq: fix uaf for accessing waker_bfqq after splitting
blk-throttle: support prioritized processing of metadata
blk-throttle: remove last_low_overflow_time
drbd: Add NULL check for net_conf to prevent dereference in state validation
nvme-tcp: fix link failure for TCP auth
blk-mq: add missing unplug trace event
mtip32xx: Remove redundant null pointer checks in mtip_hw_debugfs_init()
...
[SUBPAGE COMPRESSION LIMITS]
Currently inside writepage_delalloc(), if a delalloc range is going to
be submitted asynchronously (inline or compression, the page
dirty/writeback/unlock are all handled in at different time, not at the
submission time), then we return 1 and extent_writepage() will skip the
submission.
This is fine if every sector matches page size, but if a sector is
smaller than page size (aka, subpage case), then it can be very
problematic, for example for the following 64K page:
0 16K 32K 48K 64K
|/| |///////| |/|
| |
4K 52K
Where |/| is the dirty range we need to submit.
In the above case, we need the following different handling for the 3
ranges:
- [0, 4K) needs to be submitted for regular write
A single sector cannot be compressed.
- [16K, 32K) needs to be submitted for compressed write
- [48K, 52K) needs to be submitted for regular write.
Above, if we try to submit [16K, 32K) for compressed write, we will
return 1 and immediately, and without submitting the remaining
[48K, 52K) range.
Furthermore, since extent_writepage() will exit without unlocking any
sectors, the submitted range [0, 4K) will not have sector unlocked.
That's the reason why for now subpage is only allowed for full page
range.
[ENHANCEMENT]
- Introduce a submission bitmap at btrfs_bio_ctrl::submit_bitmap
This records which sectors will be submitted by extent_writepage_io().
This allows us to track which sectors needs to be submitted thus later
to be properly unlocked.
For asynchronously submitted range (inline/compression), the
corresponding bits will be cleared from that bitmap.
- Only return 1 if no sector needs to be submitted in
writepage_delalloc()
- Only submit sectors marked by submission bitmap inside
extent_writepage_io()
So we won't touch the asynchronously submitted part.
- Introduce btrfs_folio_end_writer_lock_bitmap() helper
This will only unlock the involved sectors specified by @bitmap
parameter, to avoid touching the range asynchronously submitted.
Please note that, since subpage compression is still limited to page
aligned range, this change is only a preparation for future sector
perfect compression support for subpage.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The function btrfs_folio_unlock_writer() is already calling
btrfs_folio_end_writer_lock() to do the heavy lifting work, the only
missing 0 writer check.
Thus there is no need to keep two different functions, move the 0 writer
check into btrfs_folio_end_writer_lock(), and remove
btrfs_folio_unlock_writer().
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
All cleanup paths lead to btrfs_path_free so path can be defined with
the automatic freeing callback in the following functions:
- btrfs_insert_orphan_item()
- btrfs_del_orphan_item()
Signed-off-by: Leo Martins <loemra.dev@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
All cleanup paths lead to btrfs_path_free so path can be defined with
the automatic freeing callback in the following functions:
- calculate_emulated_zone_size()
- calculate_alloc_pointer()
Signed-off-by: Leo Martins <loemra.dev@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add a DEFINE_FREE for struct btrfs_path. This defines a function that
can be called using the __free attribute. Define a macro
BTRFS_PATH_AUTO_FREE to make the declaration of an auto freeing path
very clear.
The intended use is to define the auto free of path in cases where the
path is allocated somewhere at the beginning and freed either on all
error paths or at the end of the function.
int func() {
BTRFS_PATH_AUTO_FREE(path);
if (...)
return -ERROR;
path = alloc_path();
...
if (...)
return -ERROR;
...
return 0;
}
Signed-off-by: Leo Martins <loemra.dev@gmail.com>
[ update changelog ]
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The function btrfs_folio_end_all_writers() is only utilized in
extent_writepage() as a way to unlock all subpage range (for both
successful submission and error handling).
Meanwhile we have a similar function, btrfs_folio_end_writer_lock().
The difference is, btrfs_folio_end_writer_lock() expects a range that is
a subset of the already locked range.
This limit on btrfs_folio_end_writer_lock() is a little overkilled,
preventing it from being utilized for error paths.
So here we enhance btrfs_folio_end_writer_lock() to accept a superset of
the locked range, and only end the locked subset.
This means we can replace btrfs_folio_end_all_writers() with
btrfs_folio_end_writer_lock() instead.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Continue adding const to parameters. This is for clarity and minor
addition to safety. There are some minor effects, in the assembly code
and .ko measured on release config.
Signed-off-by: David Sterba <dsterba@suse.com>
Currently BTRFS_I is a static inline function that takes a const inode
and returns btrfs inode, dropping the 'const' qualifier. This can break
assumptions of compiler though it seems there's no real case.
To make the parameter and return type consistent regardint const we can
use the container_of_const() that preserves it. However this would not
check the parameter type. To fix that use the same _Generic construct
but implement only the two expected types.
Signed-off-by: David Sterba <dsterba@suse.com>
We have a few places that check if we have the inode locked by doing:
ASSERT(inode_is_locked(vfs_inode));
This actually proved to be useful several times as if assertions are
enabled (and by default they are in many distros) it immediately triggers
a crash which is impossible for users to miss.
However that doesn't check if the lock is held by the calling task, so
the check passes if some other task locked the inode.
Using one of the lockdep functions to check the lock is held, like
lockdep_assert_held() for example, does check that the calling task
holds the lock, and if that's not the case it produces a warning and
stack trace in dmesg. However, despite the misleading "assert" in the
name of the lockdep helpers, it does not trigger a crash/BUG_ON(), just
a warning and splat in dmesg, which is easy to get unnoticed by users
who may have lockdep enabled.
So add a helper that does the ASSERT() and calls lockdep_assert_held()
immediately after and use it every where we check the inode is locked.
Like this if the lock is held by some other task we get the warning
in dmesg which is caught by fstests, very helpful during development,
and may also be occassionaly noticed by users with lockdep enabled.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Even in case of failure we could've discarded some data and userspace
should be made aware of it, so copy fstrim_range to userspace
regardless.
Also make sure to update the trimmed bytes amount even if
btrfs_trim_free_extents fails.
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Luca Stefani <luca.stefani.ge1@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The old page API is being gradually replaced and converted to use folio
to improve code readability and avoid repeated conversion between page
and folio. Moreover find_or_create_page() is compatible API, and it can
replaced with __filemap_get_folio(). Some interfaces have been converted
to use folio before, so the conversion operation from page can be
eliminated here.
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The old page API is being gradually replaced and converted to use folio
to improve code readability and avoid repeated conversion between page
and folio. Based on the previous patch, the compression path can be
directly used in folio without converting to page.
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The old page API is being gradually replaced and converted to use folio
to improve code readability and avoid repeated conversion between page
and folio. And memcpy_to_page() can be replaced with memcpy_to_folio().
But there is no memzero_folio(), but it can be replaced equivalently by
folio_zero_range().
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The old page API is being gradually replaced and converted to use folio
to improve code readability and avoid repeated conversion between page
and folio. And memcpy_to_page() can be replaced with memcpy_to_folio().
But there is no memzero_folio(), but it can be replaced equivalently by
folio_zero_range().
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
