We typically use __ to indicate a helper routine that shouldn't be
called directly without understanding the proper context required
to do so. We use static functions to indicate that a function is
private to a particular C file. The backref code uses static
function and __ prefixes on nearly everything, which makes the code
difficult to read and establishes a pattern for future code that
shouldn't be followed. This patch drops all the unnecessary prefixes.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Replacing the double cast and ternary conditional with a helper makes
the code easier on the eyes.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Tracepoint arguments are all read-only. If we mark the arguments
as const, we're able to keep or convert those arguments to const
where appropriate.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We have reader helpers for most of the on-disk structures that use
an extent_buffer and pointer as offset into the buffer that are
read-only. We should mark them as const and, in turn, allow consumers
of these interfaces to mark the buffers const as well.
No impact on code, but serves as documentation that a buffer is intended
not to be modified.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The sectorsize member of btrfs_block_group_cache is unused. So remove it, this
reduces the number of holes in the struct.
With patch:
/* size: 856, cachelines: 14, members: 40 */
/* sum members: 837, holes: 4, sum holes: 19 */
/* bit holes: 1, sum bit holes: 29 bits */
/* last cacheline: 24 bytes */
Without patch:
/* size: 864, cachelines: 14, members: 41 */
/* sum members: 841, holes: 5, sum holes: 23 */
/* bit holes: 1, sum bit holes: 29 bits */
/* last cacheline: 32 bytes */
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
__btrfs_alloc_chunk contains code which boils down to:
ndevs = min(ndevs, devs_max)
It's conditional upon devs_max not being 0. However, it cannot really be 0
since it's always set to either BTRFS_MAX_DEVS_SYS_CHUNK or
BTRFS_MAX_DEVS(fs_info->chunk_root). So eliminate the condition check and use
min explicitly. This has no functional changes.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
No functional changes.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
No functional changes, just make the loop a bit more readable
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull btrfs fixes from David Sterba:
"Fixes addressing problems reported by users, and there's one more
regression fix"
* 'for-4.13-part3' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: round down size diff when shrinking/growing device
Btrfs: fix early ENOSPC due to delalloc
btrfs: fix lockup in find_free_extent with read-only block groups
Btrfs: fix dir item validation when replaying xattr deletes
Further testing showed that the fix introduced in 7dfb8be11b ("btrfs:
Round down values which are written for total_bytes_size") was
insufficient and it could still lead to discrepancies between the
total_bytes in the super block and the device total bytes. So this patch
also ensures that the difference between old/new sizes when
shrinking/growing is also rounded down. This ensure that we won't be
subtracting/adding a non-sectorsize multiples to the superblock/device
total sizees.
Fixes: 7dfb8be11b ("btrfs: Round down values which are written for total_bytes_size")
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
If a lot of metadata is reserved for outstanding delayed allocations, we
rely on shrink_delalloc() to reclaim metadata space in order to fulfill
reservation tickets. However, shrink_delalloc() has a shortcut where if
it determines that space can be overcommitted, it will stop early. This
made sense before the ticketed enospc system, but now it means that
shrink_delalloc() will often not reclaim enough space to fulfill any
tickets, leading to an early ENOSPC. (Reservation tickets don't care
about being able to overcommit, they need every byte accounted for.)
Fix it by getting rid of the shortcut so that shrink_delalloc() reclaims
all of the metadata it is supposed to. This fixes early ENOSPCs we were
seeing when doing a btrfs receive to populate a new filesystem, as well
as early ENOSPCs Christoph saw when doing a big cp -r onto Btrfs.
Fixes: 957780eb27 ("Btrfs: introduce ticketed enospc infrastructure")
Tested-by: Christoph Anton Mitterer <mail@christoph.anton.mitterer.name>
Cc: stable@vger.kernel.org
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
If we have a block group that is all of the following:
1) uncached in memory
2) is read-only
3) has a disk cache state that indicates we need to recreate the cache
AND the file system has enough free space fragmentation such that the
request for an extent of a given size can't be honored;
AND have a single CPU core;
AND it's the block group with the highest starting offset such that
there are no opportunities (like reading from disk) for the loop to
yield the CPU;
We can end up with a lockup.
The root cause is simple. Once we're in the position that we've read in
all of the other block groups directly and none of those block groups
can honor the request, there are no more opportunities to sleep. We end
up trying to start a caching thread which never gets run if we only have
one core. This *should* present as a hung task waiting on the caching
thread to make some progress, but it doesn't. Instead, it degrades into
a busy loop because of the placement of the read-only check.
During the first pass through the loop, block_group->cached will be set
to BTRFS_CACHE_STARTED and have_caching_bg will be set. Then we hit the
read-only check and short circuit the loop. We're not yet in
LOOP_CACHING_WAIT, so we skip that loop back before going through the
loop again for other raid groups.
Then we move to LOOP_CACHING_WAIT state.
During the this pass through the loop, ->cached will still be
BTRFS_CACHE_STARTED, which means it's not cached, so we'll enter
cache_block_group, do a lot of nothing, and return, and also set
have_caching_bg again. Then we hit the read-only check and short circuit
the loop. The same thing happens as before except now we DO trigger
the LOOP_CACHING_WAIT && have_caching_bg check and loop back up to the
top. We do this forever.
There are two fixes in this patch since they address the same underlying
bug.
The first is to add a cond_resched to the end of the loop to ensure
that the caching thread always has an opportunity to run. This will
fix the soft lockup issue, but find_free_extent will still loop doing
nothing until the thread has completed.
The second is to move the read-only check to the top of the loop. We're
never going to return an allocation within a read-only block group so
we may as well skip it early. The check for ->cached == BTRFS_CACHE_ERROR
would cause the same problem except that BTRFS_CACHE_ERROR is considered
a "done" state and we won't re-set have_caching_bg again.
Many thanks to Stephan Kulow <coolo@suse.de> for his excellent help in
the testing process.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We were passing an incorrect slot number to the function that validates
directory items when we are replaying xattr deletes from a log tree. The
correct slot is stored at variable 'i' and not at 'path->slots[0]', so
the call to the validation function was only correct for the first
iteration of the loop, when 'i == path->slots[0]'.
After this fix, the fstest generic/066 passes again.
Fixes: 8ee8c2d62d ("btrfs: Verify dir_item in replay_xattr_deletes")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull ->s_options removal from Al Viro:
"Preparations for fsmount/fsopen stuff (coming next cycle). Everything
gets moved to explicit ->show_options(), killing ->s_options off +
some cosmetic bits around fs/namespace.c and friends. Basically, the
stuff needed to work with fsmount series with minimum of conflicts
with other work.
It's not strictly required for this merge window, but it would reduce
the PITA during the coming cycle, so it would be nice to have those
bits and pieces out of the way"
* 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
isofs: Fix isofs_show_options()
VFS: Kill off s_options and helpers
orangefs: Implement show_options
9p: Implement show_options
isofs: Implement show_options
afs: Implement show_options
affs: Implement show_options
befs: Implement show_options
spufs: Implement show_options
bpf: Implement show_options
ramfs: Implement show_options
pstore: Implement show_options
omfs: Implement show_options
hugetlbfs: Implement show_options
VFS: Don't use save/replace_mount_options if not using generic_show_options
VFS: Provide empty name qstr
VFS: Make get_filesystem() return the affected filesystem
VFS: Clean up whitespace in fs/namespace.c and fs/super.c
Provide a function to create a NUL-terminated string from unterminated data
Pull btrfs fixes from David Sterba:
"We've identified and fixed a silent corruption (introduced by code in
the first pull), a fixup after the blk_status_t merge and two fixes to
incremental send that Filipe has been hunting for some time"
* 'for-4.13-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
Btrfs: fix unexpected return value of bio_readpage_error
btrfs: btrfs_create_repair_bio never fails, skip error handling
btrfs: cloned bios must not be iterated by bio_for_each_segment_all
Btrfs: fix write corruption due to bio cloning on raid5/6
Btrfs: incremental send, fix invalid memory access
Btrfs: incremental send, fix invalid path for link commands
With blk_status_t conversion (that are now present in master),
bio_readpage_error() may return 1 as now ->submit_bio_hook() may not set
%ret if it runs without problems.
This fixes that unexpected return value by changing
btrfs_check_repairable() to return a bool instead of updating %ret, and
patch is applicable to both codebases with and without blk_status_t.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
As the function uses the non-failing bio allocation, we can remove error
handling from the callers as well.
Signed-off-by: David Sterba <dsterba@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We've started using cloned bios more in 4.13, there are some specifics
regarding the iteration. Filipe found [1] that the raid56 iterated a
cloned bio using bio_for_each_segment_all, which is incorrect. The
cloned bios have wrong bi_vcnt and this could lead to silent
corruptions. This patch adds assertions to all remaining
bio_for_each_segment_all cases.
[1] https://patchwork.kernel.org/patch/9838535/
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull btrfs fix from David Sterba:
"This fixes a user-visible bug introduced by the nowait-aio patches
merged in this cycle"
* 'nowait-aio-btrfs-fixup' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: nowait aio: Correct assignment of pos
Assigning pos for usage early messes up in append mode, where the pos is
re-assigned in generic_write_checks(). Assign pos later to get the
correct position to write from iocb->ki_pos.
Since check_can_nocow also uses the value of pos, we shift
generic_write_checks() before check_can_nocow(). Checks with IOCB_DIRECT
are present in generic_write_checks(), so checking for IOCB_NOWAIT is
enough.
Also, put locking sequence in the fast path.
This fixes a user visible bug, as reported:
"apparently breaks several shell related features on my system.
In zsh history stopped working, because no new entries are added
anymore.
I fist noticed the issue when I tried to build mplayer. It uses a shell
script to generate a help_mp.h file:
[...]
Here is a simple testcase:
% echo "foo" >> test
% echo "foo" >> test
% cat test
foo
%
"
Fixes: edf064e7c6 ("btrfs: nowait aio support")
CC: Jens Axboe <axboe@kernel.dk>
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Link: https://lkml.kernel.org/r/20170704042306.GA274@x4
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Merge tag 'for-linus-v4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux
Pull Writeback error handling updates from Jeff Layton:
"This pile represents the bulk of the writeback error handling fixes
that I have for this cycle. Some of the earlier patches in this pile
may look trivial but they are prerequisites for later patches in the
series.
The aim of this set is to improve how we track and report writeback
errors to userland. Most applications that care about data integrity
will periodically call fsync/fdatasync/msync to ensure that their
writes have made it to the backing store.
For a very long time, we have tracked writeback errors using two flags
in the address_space: AS_EIO and AS_ENOSPC. Those flags are set when a
writeback error occurs (via mapping_set_error) and are cleared as a
side-effect of filemap_check_errors (as you noted yesterday). This
model really sucks for userland.
Only the first task to call fsync (or msync or fdatasync) will see the
error. Any subsequent task calling fsync on a file will get back 0
(unless another writeback error occurs in the interim). If I have
several tasks writing to a file and calling fsync to ensure that their
writes got stored, then I need to have them coordinate with one
another. That's difficult enough, but in a world of containerized
setups that coordination may even not be possible.
But wait...it gets worse!
The calls to filemap_check_errors can be buried pretty far down in the
call stack, and there are internal callers of filemap_write_and_wait
and the like that also end up clearing those errors. Many of those
callers ignore the error return from that function or return it to
userland at nonsensical times (e.g. truncate() or stat()). If I get
back -EIO on a truncate, there is no reason to think that it was
because some previous writeback failed, and a subsequent fsync() will
(incorrectly) return 0.
This pile aims to do three things:
1) ensure that when a writeback error occurs that that error will be
reported to userland on a subsequent fsync/fdatasync/msync call,
regardless of what internal callers are doing
2) report writeback errors on all file descriptions that were open at
the time that the error occurred. This is a user-visible change,
but I think most applications are written to assume this behavior
anyway. Those that aren't are unlikely to be hurt by it.
3) document what filesystems should do when there is a writeback
error. Today, there is very little consistency between them, and a
lot of cargo-cult copying. We need to make it very clear what
filesystems should do in this situation.
To achieve this, the set adds a new data type (errseq_t) and then
builds new writeback error tracking infrastructure around that. Once
all of that is in place, we change the filesystems to use the new
infrastructure for reporting wb errors to userland.
Note that this is just the initial foray into cleaning up this mess.
There is a lot of work remaining here:
1) convert the rest of the filesystems in a similar fashion. Once the
initial set is in, then I think most other fs' will be fairly
simple to convert. Hopefully most of those can in via individual
filesystem trees.
2) convert internal waiters on writeback to use errseq_t for
detecting errors instead of relying on the AS_* flags. I have some
draft patches for this for ext4, but they are not quite ready for
prime time yet.
This was a discussion topic this year at LSF/MM too. If you're
interested in the gory details, LWN has some good articles about this:
https://lwn.net/Articles/718734/https://lwn.net/Articles/724307/"
* tag 'for-linus-v4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux:
btrfs: minimal conversion to errseq_t writeback error reporting on fsync
xfs: minimal conversion to errseq_t writeback error reporting
ext4: use errseq_t based error handling for reporting data writeback errors
fs: convert __generic_file_fsync to use errseq_t based reporting
block: convert to errseq_t based writeback error tracking
dax: set errors in mapping when writeback fails
Documentation: flesh out the section in vfs.txt on storing and reporting writeback errors
mm: set both AS_EIO/AS_ENOSPC and errseq_t in mapping_set_error
fs: new infrastructure for writeback error handling and reporting
lib: add errseq_t type and infrastructure for handling it
mm: don't TestClearPageError in __filemap_fdatawait_range
mm: clear AS_EIO/AS_ENOSPC when writeback initiation fails
jbd2: don't clear and reset errors after waiting on writeback
buffer: set errors in mapping at the time that the error occurs
fs: check for writeback errors after syncing out buffers in generic_file_fsync
buffer: use mapping_set_error instead of setting the flag
mm: fix mapping_set_error call in me_pagecache_dirty
When doing an incremental send, while processing an extent that changed
between the parent and send snapshots and that extent was an inline extent
in the parent snapshot, it's possible to access a memory region beyond
the end of leaf if the inline extent is very small and it is the first
item in a leaf.
An example scenario is described below.
The send snapshot has the following leaf:
leaf 33865728 items 33 free space 773 generation 46 owner 5
fs uuid ab7090d8-dafd-4fb9-9246-723b6d2e2fb7
chunk uuid 2d16478c-c704-4ab9-b574-68bff2281b1f
(...)
item 14 key (335 EXTENT_DATA 0) itemoff 3052 itemsize 53
generation 36 type 1 (regular)
extent data disk byte 12791808 nr 4096
extent data offset 0 nr 4096 ram 4096
extent compression 0 (none)
item 15 key (335 EXTENT_DATA 8192) itemoff 2999 itemsize 53
generation 36 type 1 (regular)
extent data disk byte 138170368 nr 225280
extent data offset 0 nr 225280 ram 225280
extent compression 0 (none)
(...)
And the parent snapshot has the following leaf:
leaf 31272960 items 17 free space 17 generation 31 owner 5
fs uuid ab7090d8-dafd-4fb9-9246-723b6d2e2fb7
chunk uuid 2d16478c-c704-4ab9-b574-68bff2281b1f
item 0 key (335 EXTENT_DATA 0) itemoff 3951 itemsize 44
generation 31 type 0 (inline)
inline extent data size 23 ram_bytes 613 compression 1 (zlib)
(...)
When computing the send stream, it is detected that the extent of inode
335, at file offset 0, and at fs/btrfs/send.c:is_extent_unchanged() we
grab the leaf from the parent snapshot and access the inline extent item.
However, before jumping to the 'out' label, we access the 'offset' and
'disk_bytenr' fields of the extent item, which should not be done for
inline extents since the inlined data starts at the offset of the
'disk_bytenr' field and can be very small. For example accessing the
'offset' field of the file extent item results in the following trace:
[ 599.705368] general protection fault: 0000 [#1] PREEMPT SMP
[ 599.706296] Modules linked in: btrfs psmouse i2c_piix4 ppdev acpi_cpufreq serio_raw parport_pc i2c_core evdev tpm_tis tpm_tis_core sg pcspkr parport tpm button su$
[ 599.709340] CPU: 7 PID: 5283 Comm: btrfs Not tainted 4.10.0-rc8-btrfs-next-46+ #1
[ 599.709340] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.1-0-gb3ef39f-prebuilt.qemu-project.org 04/01/2014
[ 599.709340] task: ffff88023eedd040 task.stack: ffffc90006658000
[ 599.709340] RIP: 0010:read_extent_buffer+0xdb/0xf4 [btrfs]
[ 599.709340] RSP: 0018:ffffc9000665ba00 EFLAGS: 00010286
[ 599.709340] RAX: db73880000000000 RBX: 0000000000000000 RCX: 0000000000000001
[ 599.709340] RDX: ffffc9000665ba60 RSI: db73880000000000 RDI: ffffc9000665ba5f
[ 599.709340] RBP: ffffc9000665ba30 R08: 0000000000000001 R09: ffff88020dc5e098
[ 599.709340] R10: 0000000000001000 R11: 0000160000000000 R12: 6db6db6db6db6db7
[ 599.709340] R13: ffff880000000000 R14: 0000000000000000 R15: ffff88020dc5e088
[ 599.709340] FS: 00007f519555a8c0(0000) GS:ffff88023f3c0000(0000) knlGS:0000000000000000
[ 599.709340] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 599.709340] CR2: 00007f1411afd000 CR3: 0000000235f8e000 CR4: 00000000000006e0
[ 599.709340] Call Trace:
[ 599.709340] btrfs_get_token_64+0x93/0xce [btrfs]
[ 599.709340] ? printk+0x48/0x50
[ 599.709340] btrfs_get_64+0xb/0xd [btrfs]
[ 599.709340] process_extent+0x3a1/0x1106 [btrfs]
[ 599.709340] ? btree_read_extent_buffer_pages+0x5/0xef [btrfs]
[ 599.709340] changed_cb+0xb03/0xb3d [btrfs]
[ 599.709340] ? btrfs_get_token_32+0x7a/0xcc [btrfs]
[ 599.709340] btrfs_compare_trees+0x432/0x53d [btrfs]
[ 599.709340] ? process_extent+0x1106/0x1106 [btrfs]
[ 599.709340] btrfs_ioctl_send+0x960/0xe26 [btrfs]
[ 599.709340] btrfs_ioctl+0x181b/0x1fed [btrfs]
[ 599.709340] ? trace_hardirqs_on_caller+0x150/0x1ac
[ 599.709340] vfs_ioctl+0x21/0x38
[ 599.709340] ? vfs_ioctl+0x21/0x38
[ 599.709340] do_vfs_ioctl+0x611/0x645
[ 599.709340] ? rcu_read_unlock+0x5b/0x5d
[ 599.709340] ? __fget+0x6d/0x79
[ 599.709340] SyS_ioctl+0x57/0x7b
[ 599.709340] entry_SYSCALL_64_fastpath+0x18/0xad
[ 599.709340] RIP: 0033:0x7f51945eec47
[ 599.709340] RSP: 002b:00007ffc21c13e98 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
[ 599.709340] RAX: ffffffffffffffda RBX: ffffffff81096459 RCX: 00007f51945eec47
[ 599.709340] RDX: 00007ffc21c13f20 RSI: 0000000040489426 RDI: 0000000000000004
[ 599.709340] RBP: ffffc9000665bf98 R08: 00007f519450d700 R09: 00007f519450d700
[ 599.709340] R10: 00007f519450d9d0 R11: 0000000000000202 R12: 0000000000000046
[ 599.709340] R13: ffffc9000665bf78 R14: 0000000000000000 R15: 00007f5195574040
[ 599.709340] ? trace_hardirqs_off_caller+0x43/0xb1
[ 599.709340] Code: 29 f0 49 39 d8 4c 0f 47 c3 49 03 81 58 01 00 00 44 89 c1 4c 01 c2 4c 29 c3 48 c1 f8 03 49 0f af c4 48 c1 e0 0c 4c 01 e8 48 01 c6 <f3> a4 31 f6 4$
[ 599.709340] RIP: read_extent_buffer+0xdb/0xf4 [btrfs] RSP: ffffc9000665ba00
[ 599.762057] ---[ end trace fe00d7af61b9f49e ]---
This is because the 'offset' field starts at an offset of 37 bytes
(offsetof(struct btrfs_file_extent_item, offset)), has a length of 8
bytes and therefore attemping to read it causes a 1 byte access beyond
the end of the leaf, as the first item's content in a leaf is located
at the tail of the leaf, the item size is 44 bytes and the offset of
that field plus its length (37 + 8 = 45) goes beyond the item's size
by 1 byte.
So fix this by accessing the 'offset' and 'disk_bytenr' fields after
jumping to the 'out' label if we are processing an inline extent. We
move the reading operation of the 'disk_bytenr' field too because we
have the same problem as for the 'offset' field explained above when
the inline data is less then 8 bytes. The access to the 'generation'
field is also moved but just for the sake of grouping access to all
the fields.
Fixes: e1cbfd7bf6 ("Btrfs: send, fix file hole not being preserved due to inline extent")
Cc: <stable@vger.kernel.org> # v4.12+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
In some scenarios an incremental send stream can contain link commands
with an invalid target path. Such scenarios happen after moving some
directory inode A, renaming a regular file inode B into the old name of
inode A and finally creating a new hard link for inode B at directory
inode A.
Consider the following example scenario where this issue happens.
Parent snapshot:
. (ino 256)
|
|--- dir1/ (ino 257)
| |--- dir2/ (ino 258)
| |--- dir3/ (ino 259)
| |--- file1 (ino 261)
| |--- dir4/ (ino 262)
|
|--- dir5/ (ino 260)
Send snapshot:
. (ino 256)
|
|--- dir1/ (ino 257)
|--- dir2/ (ino 258)
| |--- dir3/ (ino 259)
| |--- dir4 (ino 261)
|
|--- dir6/ (ino 263)
|--- dir44/ (ino 262)
|--- file11 (ino 261)
|--- dir55/ (ino 260)
When attempting to apply the corresponding incremental send stream, a
link command contains an invalid target path which makes the receiver
fail. The following is the verbose output of the btrfs receive command:
receiving snapshot mysnap2 uuid=90076fe6-5ba6-e64a-9321-9279670ed16b (...)
utimes
utimes dir1
utimes dir1/dir2/dir3
utimes
rename dir1/dir2/dir3/dir4 -> o262-7-0
link dir1/dir2/dir3/dir4 -> dir1/dir2/dir3/file1
link dir1/dir2/dir3/dir4/file11 -> dir1/dir2/dir3/file1
ERROR: link dir1/dir2/dir3/dir4/file11 -> dir1/dir2/dir3/file1 failed: Not a directory
The following steps happen during the computation of the incremental send
stream the lead to this issue:
1) When processing inode 261, we orphanize inode 262 due to a name/location
collision with one of the new hard links for inode 261 (created in the
second step below).
2) We create one of the 2 new hard links for inode 261, the one whose
location is at "dir1/dir2/dir3/dir4".
3) We then attempt to create the other new hard link for inode 261, which
has inode 262 as its parent directory. Because the path for this new
hard link was computed before we started processing the new references
(hard links), it reflects the old name/location of inode 262, that is,
it does not account for the orphanization step that happened when
we started processing the new references for inode 261, whence it is
no longer valid, causing the receiver to fail.
So fix this issue by recomputing the full path of new references if we
ended up orphanizing other inodes which are directories.
A test case for fstests follows soon.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Pull percpu updates from Tejun Heo:
"These are the percpu changes for the v4.13-rc1 merge window. There are
a couple visibility related changes - tracepoints and allocator stats
through debugfs, along with __ro_after_init markings and a cosmetic
rename in percpu_counter.
Please note that the simple O(#elements_in_the_chunk) area allocator
used by percpu allocator is again showing scalability issues,
primarily with bpf allocating and freeing large number of counters.
Dennis is working on the replacement allocator and the percpu
allocator will be seeing increased churns in the coming cycles"
* 'for-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
percpu: fix static checker warnings in pcpu_destroy_chunk
percpu: fix early calls for spinlock in pcpu_stats
percpu: resolve err may not be initialized in pcpu_alloc
percpu_counter: Rename __percpu_counter_add to percpu_counter_add_batch
percpu: add tracepoint support for percpu memory
percpu: expose statistics about percpu memory via debugfs
percpu: migrate percpu data structures to internal header
percpu: add missing lockdep_assert_held to func pcpu_free_area
mark most percpu globals as __ro_after_init
Just check and advance the errseq_t in the file before returning, and
use an errseq_t based check for writeback errors.
Other internal callers of filemap_* functions are left as-is.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
btrfs, debugfs, reiserfs and tracefs call save_mount_options() and reiserfs
calls replace_mount_options(), but they then implement their own
->show_options() methods and don't touch s_options, rendering the saved
options unnecessary. I'm trying to eliminate s_options to make it easier
to implement a context-based mount where the mount options can be passed
individually over a file descriptor.
Remove the calls to save/replace_mount_options() call in these cases.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Chris Mason <clm@fb.com>
cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cc: Steven Rostedt <rostedt@goodmis.org>
cc: linux-btrfs@vger.kernel.org
cc: reiserfs-devel@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull btrfs updates from David Sterba:
"The core updates improve error handling (mostly related to bios), with
the usual incremental work on the GFP_NOFS (mis)use removal,
refactoring or cleanups. Except the two top patches, all have been in
for-next for an extensive amount of time.
User visible changes:
- statx support
- quota override tunable
- improved compression thresholds
- obsoleted mount option alloc_start
Core updates:
- bio-related updates:
- faster bio cloning
- no allocation failures
- preallocated flush bios
- more kvzalloc use, memalloc_nofs protections, GFP_NOFS updates
- prep work for btree_inode removal
- dir-item validation
- qgoup fixes and updates
- cleanups:
- removed unused struct members, unused code, refactoring
- argument refactoring (fs_info/root, caller -> callee sink)
- SEARCH_TREE ioctl docs"
* 'for-4.13-part1' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (115 commits)
btrfs: Remove false alert when fiemap range is smaller than on-disk extent
btrfs: Don't clear SGID when inheriting ACLs
btrfs: fix integer overflow in calc_reclaim_items_nr
btrfs: scrub: fix target device intialization while setting up scrub context
btrfs: qgroup: Fix qgroup reserved space underflow by only freeing reserved ranges
btrfs: qgroup: Introduce extent changeset for qgroup reserve functions
btrfs: qgroup: Fix qgroup reserved space underflow caused by buffered write and quotas being enabled
btrfs: qgroup: Return actually freed bytes for qgroup release or free data
btrfs: qgroup: Cleanup btrfs_qgroup_prepare_account_extents function
btrfs: qgroup: Add quick exit for non-fs extents
Btrfs: rework delayed ref total_bytes_pinned accounting
Btrfs: return old and new total ref mods when adding delayed refs
Btrfs: always account pinned bytes when dropping a tree block ref
Btrfs: update total_bytes_pinned when pinning down extents
Btrfs: make BUG_ON() in add_pinned_bytes() an ASSERT()
Btrfs: make add_pinned_bytes() take an s64 num_bytes instead of u64
btrfs: fix validation of XATTR_ITEM dir items
btrfs: Verify dir_item in iterate_object_props
btrfs: Check name_len before in btrfs_del_root_ref
btrfs: Check name_len before reading btrfs_get_name
...
Pull core block/IO updates from Jens Axboe:
"This is the main pull request for the block layer for 4.13. Not a huge
round in terms of features, but there's a lot of churn related to some
core cleanups.
Note this depends on the UUID tree pull request, that Christoph
already sent out.
This pull request contains:
- A series from Christoph, unifying the error/stats codes in the
block layer. We now use blk_status_t everywhere, instead of using
different schemes for different places.
- Also from Christoph, some cleanups around request allocation and IO
scheduler interactions in blk-mq.
- And yet another series from Christoph, cleaning up how we handle
and do bounce buffering in the block layer.
- A blk-mq debugfs series from Bart, further improving on the support
we have for exporting internal information to aid debugging IO
hangs or stalls.
- Also from Bart, a series that cleans up the request initialization
differences across types of devices.
- A series from Goldwyn Rodrigues, allowing the block layer to return
failure if we will block and the user asked for non-blocking.
- Patch from Hannes for supporting setting loop devices block size to
that of the underlying device.
- Two series of patches from Javier, fixing various issues with
lightnvm, particular around pblk.
- A series from me, adding support for write hints. This comes with
NVMe support as well, so applications can help guide data placement
on flash to improve performance, latencies, and write
amplification.
- A series from Ming, improving and hardening blk-mq support for
stopping/starting and quiescing hardware queues.
- Two pull requests for NVMe updates. Nothing major on the feature
side, but lots of cleanups and bug fixes. From the usual crew.
- A series from Neil Brown, greatly improving the bio rescue set
support. Most notably, this kills the bio rescue work queues, if we
don't really need them.
- Lots of other little bug fixes that are all over the place"
* 'for-4.13/block' of git://git.kernel.dk/linux-block: (217 commits)
lightnvm: pblk: set line bitmap check under debug
lightnvm: pblk: verify that cache read is still valid
lightnvm: pblk: add initialization check
lightnvm: pblk: remove target using async. I/Os
lightnvm: pblk: use vmalloc for GC data buffer
lightnvm: pblk: use right metadata buffer for recovery
lightnvm: pblk: schedule if data is not ready
lightnvm: pblk: remove unused return variable
lightnvm: pblk: fix double-free on pblk init
lightnvm: pblk: fix bad le64 assignations
nvme: Makefile: remove dead build rule
blk-mq: map all HWQ also in hyperthreaded system
nvmet-rdma: register ib_client to not deadlock in device removal
nvme_fc: fix error recovery on link down.
nvmet_fc: fix crashes on bad opcodes
nvme_fc: Fix crash when nvme controller connection fails.
nvme_fc: replace ioabort msleep loop with completion
nvme_fc: fix double calls to nvme_cleanup_cmd()
nvme-fabrics: verify that a controller returns the correct NQN
nvme: simplify nvme_dev_attrs_are_visible
...
Commit 4751832da9 ("btrfs: fiemap: Cache and merge fiemap extent before
submit it to user") introduced a warning to catch unemitted cached
fiemap extent.
However such warning doesn't take the following case into consideration:
0 4K 8K
|<---- fiemap range --->|
|<----------- On-disk extent ------------------>|
In this case, the whole 0~8K is cached, and since it's larger than
fiemap range, it break the fiemap extent emit loop.
This leaves the fiemap extent cached but not emitted, and caught by the
final fiemap extent sanity check, causing kernel warning.
This patch removes the kernel warning and renames the sanity check to
emit_last_fiemap_cache() since it's possible and valid to have cached
fiemap extent.
Reported-by: David Sterba <dsterba@suse.cz>
Reported-by: Adam Borowski <kilobyte@angband.pl>
Fixes: 4751832da9 ("btrfs: fiemap: Cache and merge fiemap extent ...")
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When new directory 'DIR1' is created in a directory 'DIR0' with SGID bit
set, DIR1 is expected to have SGID bit set (and owning group equal to
the owning group of 'DIR0'). However when 'DIR0' also has some default
ACLs that 'DIR1' inherits, setting these ACLs will result in SGID bit on
'DIR1' to get cleared if user is not member of the owning group.
Fix the problem by moving posix_acl_update_mode() out of
__btrfs_set_acl() into btrfs_set_acl(). That way the function will not be
called when inheriting ACLs which is what we want as it prevents SGID
bit clearing and the mode has been properly set by posix_acl_create()
anyway.
Fixes: 073931017b
CC: stable@vger.kernel.org
CC: linux-btrfs@vger.kernel.org
CC: David Sterba <dsterba@suse.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: David Sterba <dsterba@suse.com>
Dave Jones hit a WARN_ON(nr < 0) in btrfs_wait_ordered_roots() with
v4.12-rc6. This was because commit 70e7af244 made it possible for
calc_reclaim_items_nr() to return a negative number. It's not really a
bug in that commit, it just didn't go far enough down the stack to find
all the possible 64->32 bit overflows.
This switches calc_reclaim_items_nr() to return a u64 and changes everyone
that uses the results of that math to u64 as well.
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Fixes: 70e7af2 ("Btrfs: fix delalloc accounting leak caused by u32 overflow")
Signed-off-by: Chris Mason <clm@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The commit "btrfs: scrub: inline helper scrub_setup_wr_ctx" inlined a
helper but wrongly sets up the target device. Incidentally there's a
local variable with the same name as a parameter in the previous
function, so this got caught during runtime as crash in test btrfs/027.
Reported-by: Chris Mason <clm@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
For the following case, btrfs can underflow qgroup reserved space
at an error path:
(Page size 4K, function name without "btrfs_" prefix)
Task A | Task B
----------------------------------------------------------------------
Buffered_write [0, 2K) |
|- check_data_free_space() |
| |- qgroup_reserve_data() |
| Range aligned to page |
| range [0, 4K) <<< |
| 4K bytes reserved <<< |
|- copy pages to page cache |
| Buffered_write [2K, 4K)
| |- check_data_free_space()
| | |- qgroup_reserved_data()
| | Range alinged to page
| | range [0, 4K)
| | Already reserved by A <<<
| | 0 bytes reserved <<<
| |- delalloc_reserve_metadata()
| | And it *FAILED* (Maybe EQUOTA)
| |- free_reserved_data_space()
|- qgroup_free_data()
Range aligned to page range
[0, 4K)
Freeing 4K
(Special thanks to Chandan for the detailed report and analyse)
[CAUSE]
Above Task B is freeing reserved data range [0, 4K) which is actually
reserved by Task A.
And at writeback time, page dirty by Task A will go through writeback
routine, which will free 4K reserved data space at file extent insert
time, causing the qgroup underflow.
[FIX]
For btrfs_qgroup_free_data(), add @reserved parameter to only free
data ranges reserved by previous btrfs_qgroup_reserve_data().
So in above case, Task B will try to free 0 byte, so no underflow.
Reported-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Tested-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Introduce a new parameter, struct extent_changeset for
btrfs_qgroup_reserved_data() and its callers.
Such extent_changeset was used in btrfs_qgroup_reserve_data() to record
which range it reserved in current reserve, so it can free it in error
paths.
The reason we need to export it to callers is, at buffered write error
path, without knowing what exactly which range we reserved in current
allocation, we can free space which is not reserved by us.
This will lead to qgroup reserved space underflow.
Reviewed-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
Under the following case, we can underflow qgroup reserved space.
Task A | Task B
---------------------------------------------------------------
Quota disabled |
Buffered write |
|- btrfs_check_data_free_space() |
| *NO* qgroup space is reserved |
| since quota is *DISABLED* |
|- All pages are copied to page |
cache |
| Enable quota
| Quota scan finished
|
| Sync_fs
| |- run_delalloc_range
| |- Write pages
| |- btrfs_finish_ordered_io
| |- insert_reserved_file_extent
| |- btrfs_qgroup_release_data()
| Since no qgroup space is
reserved in Task A, we
underflow qgroup reserved
space
This can be detected by fstest btrfs/104.
[CAUSE]
In insert_reserved_file_extent() we tell qgroup to release the @ram_bytes
size of qgroup reserved_space in all cases.
And btrfs_qgroup_release_data() will check if quotas are enabled.
However in the above case, the buffered write happens before quota is
enabled, so we don't have the reserved space for that range.
[FIX]
In insert_reserved_file_extent(), we tell qgroup to release the acctual
byte number it released.
In the above case, since we don't have the reserved space, we tell
qgroups to release 0 byte, so the problem can be fixed.
And thanks to the @reserved parameter introduced by the qgroup rework,
and previous patch to return released bytes, the fix can be as small as
10 lines.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
[ changelog updates ]
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_qgroup_release/free_data() only returns 0 or a negative error
number (ENOMEM is the only possible error).
This is normally good enough, but sometimes we need the exact byte
count it freed/released.
Change it to return actually released/freed bytenr number instead of 0
for success.
And slightly modify related extent_changeset structure, since in btrfs
one no-hole data extent won't be larger than 128M, so "unsigned int"
is large enough for the use case.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Quite a lot of qgroup corruption happens due to wrong time of calling
btrfs_qgroup_prepare_account_extents().
Since the safest time is to call it just before
btrfs_qgroup_account_extents(), there is no need to separate these 2
functions.
Merging them will make code cleaner and less bug prone.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
[ changelog and comment adjustments ]
Signed-off-by: David Sterba <dsterba@suse.com>
Modify btrfs_qgroup_account_extent() to exit quicker for non-fs extents.
The quick exit condition is:
1) The extent belongs to a non-fs tree
Only fs-tree extents can affect qgroup numbers and is the only case
where extent can be shared between different trees.
Although strictly speaking extent in data-reloc or tree-reloc tree
can be shared, data/tree-reloc root won't appear in the result of
btrfs_find_all_roots(), so we can ignore such case.
So we can check the first root in old_roots/new_roots ulist.
- if we find the 1st root is a not a fs/subvol root, then we can skip
the extent
- if we find the 1st root is a fs/subvol root, then we must continue
calculation
OR
2) both 'nr_old_roots' and 'nr_new_roots' are 0
This means either such extent got allocated then freed in current
transaction or it's a new reloc tree extent, whose nr_new_roots is 0.
Either way it won't affect qgroup accounting and can be skipped
safely.
Such quick exit can make trace output more quite and less confusing:
(example with fs uuid and time stamp removed)
Before:
------
add_delayed_tree_ref: bytenr=29556736 num_bytes=16384 action=ADD_DELAYED_REF parent=0(-) ref_root=2(EXTENT_TREE) level=0 type=TREE_BLOCK_REF seq=0
btrfs_qgroup_account_extent: bytenr=29556736 num_bytes=16384 nr_old_roots=0 nr_new_roots=1
------
Extent tree block will trigger btrfs_qgroup_account_extent() trace point
while no qgroup number is changed, as extent tree won't affect qgroup
accounting.
After:
------
add_delayed_tree_ref: bytenr=29556736 num_bytes=16384 action=ADD_DELAYED_REF parent=0(-) ref_root=2(EXTENT_TREE) level=0 type=TREE_BLOCK_REF seq=0
------
Now such unrelated extent won't trigger btrfs_qgroup_account_extent()
trace point, making the trace less noisy.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
[ changelog and comment adjustments ]
Signed-off-by: David Sterba <dsterba@suse.com>
The total_bytes_pinned counter is completely broken when accounting
delayed refs:
- If two drops for the same extent are merged, we will decrement
total_bytes_pinned twice but only increment it once.
- If an add is merged into a drop or vice versa, we will decrement the
total_bytes_pinned counter but never increment it.
- If multiple references to an extent are dropped, we will account it
multiple times, potentially vastly over-estimating the number of bytes
that will be freed by a commit and doing unnecessary work when we're
close to ENOSPC.
The last issue is relatively minor, but the first two make the
total_bytes_pinned counter leak or underflow very often. These
accounting issues were introduced in b150a4f10d ("Btrfs: use a percpu
to keep track of possibly pinned bytes"), but they were papered over by
zeroing out the counter on every commit until d288db5dc0 ("Btrfs: fix
race of using total_bytes_pinned").
We need to make sure that an extent is accounted as pinned exactly once
if and only if we will drop references to it when when the transaction
is committed. Ideally we would only add to total_bytes_pinned when the
*last* reference is dropped, but this information isn't readily
available for data extents. Again, this over-estimation can lead to
extra commits when we're close to ENOSPC, but it's not as bad as before.
The fix implemented here is to increment total_bytes_pinned when the
total refmod count for an extent goes negative and decrement it if the
refmod count goes back to non-negative or after we've run all of the
delayed refs for that extent.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We need this to decide when to account pinned bytes.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently, we only increment total_bytes_pinned in
btrfs_free_tree_block() when dropping the last reference on the block.
However, when the delayed ref is run later, we will decrement
total_bytes_pinned regardless of whether it was the last reference or
not. This causes the counter to underflow when the reference we dropped
was not the last reference. Fix it by incrementing the counter
unconditionally, which is what btrfs_free_extent() does. This makes
total_bytes_pinned an overestimate when references to shared extents are
dropped, but in the worst case this will just make us try to commit the
transaction to try to free up space and find we didn't free enough.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The extents marked in pin_down_extent() will be unpinned later in
unpin_extent_range(), which decrements total_bytes_pinned.
pin_down_extent() must increment the counter to avoid underflowing it.
Also adjust btrfs_free_tree_block() to avoid accounting for the same
extent twice.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The value of flags is one of DATA/METADATA/SYSTEM, they must exist at
when add_pinned_bytes is called.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ added changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
There are a few places where we pass in a negative num_bytes, so make it
signed for clarity. Also move it up in the file since later patches will
need it there.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The XATTR_ITEM is a type of a directory item so we use the common
validator helper. Unlike other dir items, it can have data. The way the
name len validation is currently implemented does not reflect that. We'd
have to adjust by the data_len when comparing the read and item limits.
However, this will not work for multi-item xattr dir items.
Example from tree dump of generic/337:
item 7 key (257 XATTR_ITEM 751495445) itemoff 15667 itemsize 147
location key (0 UNKNOWN.0 0) type XATTR
transid 8 data_len 3 name_len 11
name: user.foobar
data 123
location key (0 UNKNOWN.0 0) type XATTR
transid 8 data_len 6 name_len 13
name: user.WvG1c1Td
data qwerty
location key (0 UNKNOWN.0 0) type XATTR
transid 8 data_len 5 name_len 19
name: user.J3__T_Km3dVsW_
data hello
At the point of btrfs_is_name_len_valid call we don't have access to the
data_len value of the 2nd and 3rd sub-item. So simple btrfs_dir_data_len(leaf,
di) would always return 3, although we'd need to get 6 and 5 respectively to
get the claculations right. (read_end + name_len + data_len vs item_end)
We'd have to also pass data_len externally, which is not point of the
name validation. The last check is supposed to test if there's at least
one dir item space after the one we're processing. I don't think this is
particularly useful, validation of the next item would catch that too.
So the check is removed and we don't weaken the validation. Now tests
btrfs/048, btrfs/053, generic/273 and generic/337 pass.
Signed-off-by: David Sterba <dsterba@suse.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Chris Mason <clm@fb.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Call verify_dir_item before memcmp_extent_buffer reading name from
dir_item.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_del_root_ref calls btrfs_search_slot and reads name from root_ref.
Call btrfs_is_name_len_valid before memcmp.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
