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12,099 commits

Author SHA1 Message Date
Chris Mason
c4b460b5fa btrfs: only subtract from len_to_oe_boundary when it is tracking an extent
commit 09c3717c3a upstream.

bio_ctrl->len_to_oe_boundary is used to make sure we stay inside a zone
as we submit bios for writes.  Every time we add a page to the bio, we
decrement those bytes from len_to_oe_boundary, and then we submit the
bio if we happen to hit zero.

Most of the time, len_to_oe_boundary gets set to U32_MAX.
submit_extent_page() adds pages into our bio, and the size of the bio
ends up limited by:

- Are we contiguous on disk?
- Does bio_add_page() allow us to stuff more in?
- is len_to_oe_boundary > 0?

The len_to_oe_boundary math starts with U32_MAX, which isn't page or
sector aligned, and subtracts from it until it hits zero.  In the
non-zoned case, the last IO we submit before we hit zero is going to be
unaligned, triggering BUGs.

This is hard to trigger because bio_add_page() isn't going to make a bio
of U32_MAX size unless you give it a perfect set of pages and fully
contiguous extents on disk.  We can hit it pretty reliably while making
large swapfiles during provisioning because the machine is freshly
booted, mostly idle, and the disk is freshly formatted.  It's also
possible to trigger with reads when read_ahead_kb is set to 4GB.

The code has been clean up and shifted around a few times, but this flaw
has been lurking since the counter was added.  I think the commit
24e6c80822 ("btrfs: simplify main loop in submit_extent_page") ended
up exposing the bug.

The fix used here is to skip doing math on len_to_oe_boundary unless
we've changed it from the default U32_MAX value.  bio_add_page() is the
real limit we want, and there's no reason to do extra math when block
layer is doing it for us.

Sample reproducer, note you'll need to change the path to the bdi and
device:

  SUBVOL=/btrfs/swapvol
  SWAPFILE=$SUBVOL/swapfile
  SZMB=8192

  mkfs.btrfs -f /dev/vdb
  mount /dev/vdb /btrfs

  btrfs subvol create $SUBVOL
  chattr +C $SUBVOL
  dd if=/dev/zero of=$SWAPFILE bs=1M count=$SZMB
  sync

  echo 4 > /proc/sys/vm/drop_caches

  echo 4194304 > /sys/class/bdi/btrfs-2/read_ahead_kb

  while true; do
	  echo 1 > /proc/sys/vm/drop_caches
	  echo 1 > /proc/sys/vm/drop_caches
	  dd of=/dev/zero if=$SWAPFILE bs=4096M count=2 iflag=fullblock
  done

Fixes: 24e6c80822 ("btrfs: simplify main loop in submit_extent_page")
CC: stable@vger.kernel.org # 6.4+
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-23 17:32:39 +02:00
Anand Jain
8add2a9644 btrfs: fix replace/scrub failure with metadata_uuid
commit b471965fdb upstream.

Fstests with POST_MKFS_CMD="btrfstune -m" (as in the mailing list)
reported a few of the test cases failing.

The failure scenario can be summarized and simplified as follows:

  $ mkfs.btrfs -fq -draid1 -mraid1 /dev/sdb1 /dev/sdb2 :0
  $ btrfstune -m /dev/sdb1 :0
  $ wipefs -a /dev/sdb1 :0
  $ mount -o degraded /dev/sdb2 /btrfs :0
  $ btrfs replace start -B -f -r 1 /dev/sdb1 /btrfs :1
    STDERR:
    ERROR: ioctl(DEV_REPLACE_START) failed on "/btrfs": Input/output error

  [11290.583502] BTRFS warning (device sdb2): tree block 22036480 mirror 2 has bad fsid, has 99835c32-49f0-4668-9e66-dc277a96b4a6 want da40350c-33ac-4872-92a8-4948ed8c04d0
  [11290.586580] BTRFS error (device sdb2): unable to fix up (regular) error at logical 22020096 on dev /dev/sdb8 physical 1048576

As above, the replace is failing because we are verifying the header with
fs_devices::fsid instead of fs_devices::metadata_uuid, despite the
metadata_uuid actually being present.

To fix this, use fs_devices::metadata_uuid. We copy fsid into
fs_devices::metadata_uuid if there is no metadata_uuid, so its fine.

Fixes: a3ddbaebc7 ("btrfs: scrub: introduce a helper to verify one metadata block")
CC: stable@vger.kernel.org # 6.4+
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-23 17:32:39 +02:00
xiaoshoukui
ae81329f7d btrfs: fix BUG_ON condition in btrfs_cancel_balance
commit 29eefa6d0d upstream.

Pausing and canceling balance can race to interrupt balance lead to BUG_ON
panic in btrfs_cancel_balance. The BUG_ON condition in btrfs_cancel_balance
does not take this race scenario into account.

However, the race condition has no other side effects. We can fix that.

Reproducing it with panic trace like this:

  kernel BUG at fs/btrfs/volumes.c:4618!
  RIP: 0010:btrfs_cancel_balance+0x5cf/0x6a0
  Call Trace:
   <TASK>
   ? do_nanosleep+0x60/0x120
   ? hrtimer_nanosleep+0xb7/0x1a0
   ? sched_core_clone_cookie+0x70/0x70
   btrfs_ioctl_balance_ctl+0x55/0x70
   btrfs_ioctl+0xa46/0xd20
   __x64_sys_ioctl+0x7d/0xa0
   do_syscall_64+0x38/0x80
   entry_SYSCALL_64_after_hwframe+0x63/0xcd

  Race scenario as follows:
  > mutex_unlock(&fs_info->balance_mutex);
  > --------------------
  > .......issue pause and cancel req in another thread
  > --------------------
  > ret = __btrfs_balance(fs_info);
  >
  > mutex_lock(&fs_info->balance_mutex);
  > if (ret == -ECANCELED && atomic_read(&fs_info->balance_pause_req)) {
  >         btrfs_info(fs_info, "balance: paused");
  >         btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED);
  > }

CC: stable@vger.kernel.org # 4.19+
Signed-off-by: xiaoshoukui <xiaoshoukui@ruijie.com.cn>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-23 17:32:38 +02:00
Josef Bacik
b43a4c99d8 btrfs: fix incorrect splitting in btrfs_drop_extent_map_range
commit c962098ca4 upstream.

In production we were seeing a variety of WARN_ON()'s in the extent_map
code, specifically in btrfs_drop_extent_map_range() when we have to call
add_extent_mapping() for our second split.

Consider the following extent map layout

	PINNED
	[0 16K)  [32K, 48K)

and then we call btrfs_drop_extent_map_range for [0, 36K), with
skip_pinned == true.  The initial loop will have

	start = 0
	end = 36K
	len = 36K

we will find the [0, 16k) extent, but since we are pinned we will skip
it, which has this code

	start = em_end;
	if (end != (u64)-1)
		len = start + len - em_end;

em_end here is 16K, so now the values are

	start = 16K
	len = 16K + 36K - 16K = 36K

len should instead be 20K.  This is a problem when we find the next
extent at [32K, 48K), we need to split this extent to leave [36K, 48k),
however the code for the split looks like this

	split->start = start + len;
	split->len = em_end - (start + len);

In this case we have

	em_end = 48K
	split->start = 16K + 36K       // this should be 16K + 20K
	split->len = 48K - (16K + 36K) // this overflows as 16K + 36K is 52K

and now we have an invalid extent_map in the tree that potentially
overlaps other entries in the extent map.  Even in the non-overlapping
case we will have split->start set improperly, which will cause problems
with any block related calculations.

We don't actually need len in this loop, we can simply use end as our
end point, and only adjust start up when we find a pinned extent we need
to skip.

Adjust the logic to do this, which keeps us from inserting an invalid
extent map.

We only skip_pinned in the relocation case, so this is relatively rare,
except in the case where you are running relocation a lot, which can
happen with auto relocation on.

Fixes: 55ef689900 ("Btrfs: Fix btrfs_drop_extent_cache for skip pinned case")
CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-23 17:32:38 +02:00
Filipe Manana
5441532ffc btrfs: fix infinite directory reads
commit 9b378f6ad4 upstream.

The readdir implementation currently processes always up to the last index
it finds. This however can result in an infinite loop if the directory has
a large number of entries such that they won't all fit in the given buffer
passed to the readdir callback, that is, dir_emit() returns a non-zero
value. Because in that case readdir() will be called again and if in the
meanwhile new directory entries were added and we still can't put all the
remaining entries in the buffer, we keep repeating this over and over.

The following C program and test script reproduce the problem:

  $ cat /mnt/readdir_prog.c
  #include <sys/types.h>
  #include <dirent.h>
  #include <stdio.h>

  int main(int argc, char *argv[])
  {
    DIR *dir = opendir(".");
    struct dirent *dd;

    while ((dd = readdir(dir))) {
      printf("%s\n", dd->d_name);
      rename(dd->d_name, "TEMPFILE");
      rename("TEMPFILE", dd->d_name);
    }
    closedir(dir);
  }

  $ gcc -o /mnt/readdir_prog /mnt/readdir_prog.c

  $ cat test.sh
  #!/bin/bash

  DEV=/dev/sdi
  MNT=/mnt/sdi

  mkfs.btrfs -f $DEV &> /dev/null
  #mkfs.xfs -f $DEV &> /dev/null
  #mkfs.ext4 -F $DEV &> /dev/null

  mount $DEV $MNT

  mkdir $MNT/testdir
  for ((i = 1; i <= 2000; i++)); do
      echo -n > $MNT/testdir/file_$i
  done

  cd $MNT/testdir
  /mnt/readdir_prog

  cd /mnt

  umount $MNT

This behaviour is surprising to applications and it's unlike ext4, xfs,
tmpfs, vfat and other filesystems, which always finish. In this case where
new entries were added due to renames, some file names may be reported
more than once, but this varies according to each filesystem - for example
ext4 never reported the same file more than once while xfs reports the
first 13 file names twice.

So change our readdir implementation to track the last index number when
opendir() is called and then make readdir() never process beyond that
index number. This gives the same behaviour as ext4.

Reported-by: Rob Landley <rob@landley.net>
Link: https://lore.kernel.org/linux-btrfs/2c8c55ec-04c6-e0dc-9c5c-8c7924778c35@landley.net/
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217681
CC: stable@vger.kernel.org # 6.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-23 17:32:38 +02:00
Filipe Manana
7569c4294b btrfs: fix use-after-free of new block group that became unused
[ Upstream commit 0657b20c5a ]

If a task creates a new block group and that block group becomes unused
before we finish its creation, at btrfs_create_pending_block_groups(),
then when btrfs_mark_bg_unused() is called against the block group, we
assume that the block group is currently in the list of block groups to
reclaim, and we move it out of the list of new block groups and into the
list of unused block groups. This has two consequences:

1) We move it out of the list of new block groups associated to the
   current transaction. So the block group creation is not finished and
   if we attempt to delete the bg because it's unused, we will not find
   the block group item in the extent tree (or the new block group tree),
   its device extent items in the device tree etc, resulting in the
   deletion to fail due to the missing items;

2) We don't increment the reference count on the block group when we
   move it to the list of unused block groups, because we assumed the
   block group was on the list of block groups to reclaim, and in that
   case it already has the correct reference count. However the block
   group was on the list of new block groups, in which case no extra
   reference was taken because it's local to the current task. This
   later results in doing an extra reference count decrement when
   removing the block group from the unused list, eventually leading the
   reference count to 0.

This second case was caught when running generic/297 from fstests, which
produced the following assertion failure and stack trace:

  [589.559] assertion failed: refcount_read(&block_group->refs) == 1, in fs/btrfs/block-group.c:4299
  [589.559] ------------[ cut here ]------------
  [589.559] kernel BUG at fs/btrfs/block-group.c:4299!
  [589.560] invalid opcode: 0000 [#1] PREEMPT SMP PTI
  [589.560] CPU: 8 PID: 2819134 Comm: umount Tainted: G        W          6.4.0-rc6-btrfs-next-134+ #1
  [589.560] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014
  [589.560] RIP: 0010:btrfs_free_block_groups+0x449/0x4a0 [btrfs]
  [589.561] Code: 68 62 da c0 (...)
  [589.561] RSP: 0018:ffffa55a8c3b3d98 EFLAGS: 00010246
  [589.561] RAX: 0000000000000058 RBX: ffff8f030d7f2000 RCX: 0000000000000000
  [589.562] RDX: 0000000000000000 RSI: ffffffff953f0878 RDI: 00000000ffffffff
  [589.562] RBP: ffff8f030d7f2088 R08: 0000000000000000 R09: ffffa55a8c3b3c50
  [589.562] R10: 0000000000000001 R11: 0000000000000001 R12: ffff8f05850b4c00
  [589.562] R13: ffff8f030d7f2090 R14: ffff8f05850b4cd8 R15: dead000000000100
  [589.563] FS:  00007f497fd2e840(0000) GS:ffff8f09dfc00000(0000) knlGS:0000000000000000
  [589.563] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [589.563] CR2: 00007f497ff8ec10 CR3: 0000000271472006 CR4: 0000000000370ee0
  [589.563] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [589.564] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [589.564] Call Trace:
  [589.564]  <TASK>
  [589.565]  ? __die_body+0x1b/0x60
  [589.565]  ? die+0x39/0x60
  [589.565]  ? do_trap+0xeb/0x110
  [589.565]  ? btrfs_free_block_groups+0x449/0x4a0 [btrfs]
  [589.566]  ? do_error_trap+0x6a/0x90
  [589.566]  ? btrfs_free_block_groups+0x449/0x4a0 [btrfs]
  [589.566]  ? exc_invalid_op+0x4e/0x70
  [589.566]  ? btrfs_free_block_groups+0x449/0x4a0 [btrfs]
  [589.567]  ? asm_exc_invalid_op+0x16/0x20
  [589.567]  ? btrfs_free_block_groups+0x449/0x4a0 [btrfs]
  [589.567]  ? btrfs_free_block_groups+0x449/0x4a0 [btrfs]
  [589.567]  close_ctree+0x35d/0x560 [btrfs]
  [589.568]  ? fsnotify_sb_delete+0x13e/0x1d0
  [589.568]  ? dispose_list+0x3a/0x50
  [589.568]  ? evict_inodes+0x151/0x1a0
  [589.568]  generic_shutdown_super+0x73/0x1a0
  [589.569]  kill_anon_super+0x14/0x30
  [589.569]  btrfs_kill_super+0x12/0x20 [btrfs]
  [589.569]  deactivate_locked_super+0x2e/0x70
  [589.569]  cleanup_mnt+0x104/0x160
  [589.570]  task_work_run+0x56/0x90
  [589.570]  exit_to_user_mode_prepare+0x160/0x170
  [589.570]  syscall_exit_to_user_mode+0x22/0x50
  [589.570]  ? __x64_sys_umount+0x12/0x20
  [589.571]  do_syscall_64+0x48/0x90
  [589.571]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
  [589.571] RIP: 0033:0x7f497ff0a567
  [589.571] Code: af 98 0e (...)
  [589.572] RSP: 002b:00007ffc98347358 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
  [589.572] RAX: 0000000000000000 RBX: 00007f49800b8264 RCX: 00007f497ff0a567
  [589.572] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000557f558abfa0
  [589.573] RBP: 0000557f558a6ba0 R08: 0000000000000000 R09: 00007ffc98346100
  [589.573] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
  [589.573] R13: 0000557f558abfa0 R14: 0000557f558a6cb0 R15: 0000557f558a6dd0
  [589.573]  </TASK>
  [589.574] Modules linked in: dm_snapshot dm_thin_pool (...)
  [589.576] ---[ end trace 0000000000000000 ]---

Fix this by adding a runtime flag to the block group to tell that the
block group is still in the list of new block groups, and therefore it
should not be moved to the list of unused block groups, at
btrfs_mark_bg_unused(), until the flag is cleared, when we finish the
creation of the block group at btrfs_create_pending_block_groups().

Fixes: a9f189716c ("btrfs: move out now unused BG from the reclaim list")
CC: stable@vger.kernel.org # 5.15+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-23 17:32:35 +02:00
Naohiro Aota
5d19abcffd btrfs: move out now unused BG from the reclaim list
[ Upstream commit a9f189716c ]

An unused block group is easy to remove to free up space and should be
reclaimed fast. Such block group can often already be a target of the
reclaim process. As we check list_empty(&bg->bg_list), we keep it in the
reclaim list. That block group is never reclaimed until the file system
is filled e.g. up to 75%.

Instead, we can move unused block group to the unused list and delete it
fast.

Fixes: 18bb8bbf13 ("btrfs: zoned: automatically reclaim zones")
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Filipe Manana <fdmanana@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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-23 17:32:35 +02:00
Josef Bacik
e044b1b286 btrfs: set cache_block_group_error if we find an error
commit 92fb94b69c upstream.

We set cache_block_group_error if btrfs_cache_block_group() returns an
error, this is because we could end up not finding space to allocate and
mistakenly return -ENOSPC, and which could then abort the transaction
with the incorrect errno, and in the case of ENOSPC result in a
WARN_ON() that will trip up tests like generic/475.

However there's the case where multiple threads can be racing, one
thread gets the proper error, and the other thread doesn't actually call
btrfs_cache_block_group(), it instead sees ->cached ==
BTRFS_CACHE_ERROR.  Again the result is the same, we fail to allocate
our space and return -ENOSPC.  Instead we need to set
cache_block_group_error to -EIO in this case to make sure that if we do
not make our allocation we get the appropriate error returned back to
the caller.

CC: stable@vger.kernel.org # 4.14+
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-16 18:32:30 +02:00
Qu Wenruo
84256e00ee btrfs: reject invalid reloc tree root keys with stack dump
commit 6ebcd021c9 upstream.

[BUG]
Syzbot reported a crash that an ASSERT() got triggered inside
prepare_to_merge().

That ASSERT() makes sure the reloc tree is properly pointed back by its
subvolume tree.

[CAUSE]
After more debugging output, it turns out we had an invalid reloc tree:

  BTRFS error (device loop1): reloc tree mismatch, root 8 has no reloc root, expect reloc root key (-8, 132, 8) gen 17

Note the above root key is (TREE_RELOC_OBJECTID, ROOT_ITEM,
QUOTA_TREE_OBJECTID), meaning it's a reloc tree for quota tree.

But reloc trees can only exist for subvolumes, as for non-subvolume
trees, we just COW the involved tree block, no need to create a reloc
tree since those tree blocks won't be shared with other trees.

Only subvolumes tree can share tree blocks with other trees (thus they
have BTRFS_ROOT_SHAREABLE flag).

Thus this new debug output proves my previous assumption that corrupted
on-disk data can trigger that ASSERT().

[FIX]
Besides the dedicated fix and the graceful exit, also let tree-checker to
check such root keys, to make sure reloc trees can only exist for subvolumes.

CC: stable@vger.kernel.org # 5.15+
Reported-by: syzbot+ae97a827ae1c3336bbb4@syzkaller.appspotmail.com
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-16 18:32:30 +02:00
Qu Wenruo
a96b6519ac btrfs: exit gracefully if reloc roots don't match
commit 05d7ce5045 upstream.

[BUG]
Syzbot reported a crash that an ASSERT() got triggered inside
prepare_to_merge().

[CAUSE]
The root cause of the triggered ASSERT() is we can have a race between
quota tree creation and relocation.

This leads us to create a duplicated quota tree in the
btrfs_read_fs_root() path, and since it's treated as fs tree, it would
have ROOT_SHAREABLE flag, causing us to create a reloc tree for it.

The bug itself is fixed by a dedicated patch for it, but this already
taught us the ASSERT() is not something straightforward for
developers.

[ENHANCEMENT]
Instead of using an ASSERT(), let's handle it gracefully and output
extra info about the mismatch reloc roots to help debug.

Also with the above ASSERT() removed, we can trigger ASSERT(0)s inside
merge_reloc_roots() later.
Also replace those ASSERT(0)s with WARN_ON()s.

CC: stable@vger.kernel.org # 5.15+
Reported-by: syzbot+ae97a827ae1c3336bbb4@syzkaller.appspotmail.com
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-16 18:32:30 +02:00
Christoph Hellwig
663c9949ba btrfs: properly clear end of the unreserved range in cow_file_range
commit 12b2d64e59 upstream.

When the call to btrfs_reloc_clone_csums in cow_file_range returns an
error, we jump to the out_unlock label with the extent_reserved variable
set to false.   The cleanup at the label will then call
extent_clear_unlock_delalloc on the range from start to end.  But we've
already added cur_alloc_size to start before the jump, so there might no
range be left from the newly incremented start to end.  Move the check for
'start < end' so that it is reached by also for the !extent_reserved case.

CC: stable@vger.kernel.org # 6.1+
Fixes: a315e68f6e ("Btrfs: fix invalid attempt to free reserved space on failure to cow range")
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-16 18:32:30 +02:00
Christoph Hellwig
15da6eaecc btrfs: don't wait for writeback on clean pages in extent_write_cache_pages
commit 5c25699871 upstream.

__extent_writepage could have started on more pages than the one it was
called for.  This happens regularly for zoned file systems, and in theory
could happen for compressed I/O if the worker thread was executed very
quickly. For such pages extent_write_cache_pages waits for writeback
to complete before moving on to the next page, which is highly inefficient
as it blocks the flusher thread.

Port over the PageDirty check that was added to write_cache_pages in
commit 515f4a037f ("mm: write_cache_pages optimise page cleaning") to
fix this.

CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-16 18:32:29 +02:00
Christoph Hellwig
f1f2e3a418 btrfs: don't stop integrity writeback too early
commit effa24f689 upstream.

extent_write_cache_pages stops writing pages as soon as nr_to_write hits
zero.  That is the right thing for opportunistic writeback, but incorrect
for data integrity writeback, which needs to ensure that no dirty pages
are left in the range.  Thus only stop the writeback for WB_SYNC_NONE
if nr_to_write hits 0.

This is a port of write_cache_pages changes in commit 05fe478dd0
("mm: write_cache_pages integrity fix").

Note that I've only trigger the problem with other changes to the btrfs
writeback code, but this condition seems worthwhile fixing anyway.

CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
[ updated comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-16 18:32:29 +02:00
Josef Bacik
793525c287 btrfs: wait for actual caching progress during allocation
commit fc1f91b923 upstream.

Recently we've been having mysterious hangs while running generic/475 on
the CI system.  This turned out to be something like this:

  Task 1
  dmsetup suspend --nolockfs
  -> __dm_suspend
   -> dm_wait_for_completion
    -> dm_wait_for_bios_completion
     -> Unable to complete because of IO's on a plug in Task 2

  Task 2
  wb_workfn
  -> wb_writeback
   -> blk_start_plug
    -> writeback_sb_inodes
     -> Infinite loop unable to make an allocation

  Task 3
  cache_block_group
  ->read_extent_buffer_pages
   ->Waiting for IO to complete that can't be submitted because Task 1
     suspended the DM device

The problem here is that we need Task 2 to be scheduled completely for
the blk plug to flush.  Normally this would happen, we normally wait for
the block group caching to finish (Task 3), and this schedule would
result in the block plug flushing.

However if there's enough free space available from the current caching
to satisfy the allocation we won't actually wait for the caching to
complete.  This check however just checks that we have enough space, not
that we can make the allocation.  In this particular case we were trying
to allocate 9MiB, and we had 10MiB of free space, but we didn't have
9MiB of contiguous space to allocate, and thus the allocation failed and
we looped.

We specifically don't cycle through the FFE loop until we stop finding
cached block groups because we don't want to allocate new block groups
just because we're caching, so we short circuit the normal loop once we
hit LOOP_CACHING_WAIT and we found a caching block group.

This is normally fine, except in this particular case where the caching
thread can't make progress because the DM device has been suspended.

Fix this by not only waiting for free space to >= the amount of space we
want to allocate, but also that we make some progress in caching from
the time we start waiting.  This will keep us from busy looping when the
caching is taking a while but still theoretically has enough space for
us to allocate from, and fixes this particular case by forcing us to
actually sleep and wait for forward progress, which will flush the plug.

With this fix we're no longer hanging with generic/475.

CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-16 18:32:29 +02:00
Filipe Manana
f775ceb0cb btrfs: remove BUG_ON()'s in add_new_free_space()
commit d8ccbd2191 upstream.

At add_new_free_space() we have these BUG_ON()'s that are there to deal
with any failure to add free space to the in memory free space cache.
Such failures are mostly -ENOMEM that should be very rare. However there's
no need to have these BUG_ON()'s, we can just return any error to the
caller and all callers and their upper call chain are already dealing with
errors.

So just make add_new_free_space() return any errors, while removing the
BUG_ON()'s, and returning the total amount of added free space to an
optional u64 pointer argument.

Reported-by: syzbot+3ba856e07b7127889d8c@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/000000000000e9cb8305ff4e8327@google.com/
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-11 12:14:25 +02:00
Filipe Manana
db73d812bb btrfs: check for commit error at btrfs_attach_transaction_barrier()
commit b28ff3a7d7 upstream.

btrfs_attach_transaction_barrier() is used to get a handle pointing to the
current running transaction if the transaction has not started its commit
yet (its state is < TRANS_STATE_COMMIT_START). If the transaction commit
has started, then we wait for the transaction to commit and finish before
returning - however we completely ignore if the transaction was aborted
due to some error during its commit, we simply return ERR_PT(-ENOENT),
which makes the caller assume everything is fine and no errors happened.

This could make an fsync return success (0) to user space when in fact we
had a transaction abort and the target inode changes were therefore not
persisted.

Fix this by checking for the return value from btrfs_wait_for_commit(),
and if it returned an error, return it back to the caller.

Fixes: d4edf39bd5 ("Btrfs: fix uncompleted transaction")
CC: stable@vger.kernel.org # 4.19+
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-03 10:26:07 +02:00
Filipe Manana
ec0a56ae95 btrfs: check if the transaction was aborted at btrfs_wait_for_commit()
commit bf7ecbe987 upstream.

At btrfs_wait_for_commit() we wait for a transaction to finish and then
always return 0 (success) without checking if it was aborted, in which
case the transaction didn't happen due to some critical error. Fix this
by checking if the transaction was aborted.

Fixes: 462045928b ("Btrfs: add START_SYNC, WAIT_SYNC ioctls")
CC: stable@vger.kernel.org # 4.19+
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-03 10:26:07 +02:00
Filipe Manana
1e8087589b btrfs: account block group tree when calculating global reserve size
commit 8dbfc14fc7 upstream.

When using the block group tree feature, this tree is a critical tree just
like the extent, csum and free space trees, and just like them it uses the
delayed refs block reserve.

So take into account the block group tree, and its current size, when
calculating the size for the global reserve.

CC: stable@vger.kernel.org # 6.1+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-03 10:26:07 +02:00
Naohiro Aota
2c28c5c52e btrfs: zoned: do not enable async discard
commit 95ca6599a5 upstream.

The zoned mode need to reset a zone before using it. We rely on btrfs's
original discard functionality (discarding unused block group range) to do
the resetting.

While the commit 63a7cb1307 ("btrfs: auto enable discard=async when
possible") made the discard done in an async manner, a zoned reset do not
need to be async, as it is fast enough.

Even worth, delaying zone rests prevents using those zones again. So, let's
disable async discard on the zoned mode.

Fixes: 63a7cb1307 ("btrfs: auto enable discard=async when possible")
CC: stable@vger.kernel.org # 6.3+
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update message text ]
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-03 10:26:07 +02:00
Filipe Manana
50cafe0581 btrfs: fix race between quota disable and relocation
[ Upstream commit 8a4a0b2a3e ]

If we disable quotas while we have a relocation of a metadata block group
that has extents belonging to the quota root, we can cause the relocation
to fail with -ENOENT. This is because relocation builds backref nodes for
extents of the quota root and later needs to walk the backrefs and access
the quota root - however if in between a task disables quotas, it results
in deleting the quota root from the root tree (with btrfs_del_root(),
called from btrfs_quota_disable().

This can be sporadically triggered by test case btrfs/255 from fstests:

  $ ./check btrfs/255
  FSTYP         -- btrfs
  PLATFORM      -- Linux/x86_64 debian0 6.4.0-rc6-btrfs-next-134+ #1 SMP PREEMPT_DYNAMIC Thu Jun 15 11:59:28 WEST 2023
  MKFS_OPTIONS  -- /dev/sdc
  MOUNT_OPTIONS -- /dev/sdc /home/fdmanana/btrfs-tests/scratch_1

  btrfs/255 6s ... _check_dmesg: something found in dmesg (see /home/fdmanana/git/hub/xfstests/results//btrfs/255.dmesg)
  - output mismatch (see /home/fdmanana/git/hub/xfstests/results//btrfs/255.out.bad)
#      --- tests/btrfs/255.out	2023-03-02 21:47:53.876609426 +0000
#      +++ /home/fdmanana/git/hub/xfstests/results//btrfs/255.out.bad	2023-06-16 10:20:39.267563212 +0100
#      @@ -1,2 +1,4 @@
#       QA output created by 255
#      +ERROR: error during balancing '/home/fdmanana/btrfs-tests/scratch_1': No such file or directory
#      +There may be more info in syslog - try dmesg | tail
#       Silence is golden
#      ...
      (Run 'diff -u /home/fdmanana/git/hub/xfstests/tests/btrfs/255.out /home/fdmanana/git/hub/xfstests/results//btrfs/255.out.bad'  to see the entire diff)
  Ran: btrfs/255
  Failures: btrfs/255
  Failed 1 of 1 tests

To fix this make the quota disable operation take the cleaner mutex, as
relocation of a block group also takes this mutex. This is also what we
do when deleting a subvolume/snapshot, we take the cleaner mutex in the
cleaner kthread (at cleaner_kthread()) and then we call btrfs_del_root()
at btrfs_drop_snapshot() while under the protection of the cleaner mutex.

Fixes: bed92eae26 ("Btrfs: qgroup implementation and prototypes")
CC: stable@vger.kernel.org # 5.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-03 10:25:43 +02:00
Christoph Hellwig
693a761758 btrfs: fix fsverify read error handling in end_page_read
[ Upstream commit 2c14f0ffdd ]

Also clear the uptodate bit to make sure the page isn't seen as uptodate
in the page cache if fsverity verification fails.

Fixes: 146054090b ("btrfs: initial fsverity support")
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-03 10:25:43 +02:00
Christoph Hellwig
c42d836e2e btrfs: factor out a btrfs_verify_page helper
[ Upstream commit ed9ee98ecb ]

Split all the conditionals for the fsverity calls in end_page_read into
a btrfs_verify_page helper to keep the code readable and make additional
refactoring easier.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Stable-dep-of: 2c14f0ffdd ("btrfs: fix fsverify read error handling in end_page_read")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-03 10:25:42 +02:00
Christoph Hellwig
0d7c5934f0 btrfs: be a bit more careful when setting mirror_num_ret in btrfs_map_block
[ Upstream commit 4e7de35eb7 ]

The mirror_num_ret is allowed to be NULL, although it has to be set when
smap is set.  Unfortunately that is not a well enough specifiable
invariant for static type checkers, so add a NULL check to make sure they
are fine.

Fixes: 03793cbbc8 ("btrfs: add fast path for single device io in __btrfs_map_block")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-27 08:56:54 +02:00
Filipe Manana
951b87d8ba btrfs: abort transaction at update_ref_for_cow() when ref count is zero
[ Upstream commit eced687e22 ]

At update_ref_for_cow() we are calling btrfs_handle_fs_error() if we find
that the extent buffer has an unexpected ref count of zero, however we can
simply use btrfs_abort_transaction(), which achieves the same purposes: to
turn the fs to error state, abort the current transaction and turn the fs
to RO mode as well. Besides that, btrfs_abort_transaction() also prints a
stack trace which makes it more useful.

Also, as this is a very unexpected situation, indicating a serious
corruption/inconsistency, tag the if branch as 'unlikely', set the error
code to -EUCLEAN instead of -EROFS, and log an explicit message.

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-27 08:56:46 +02:00
Christoph Hellwig
d40be032ec btrfs: don't check PageError in __extent_writepage
[ Upstream commit 3e92499e3b ]

__extent_writepage currenly sets PageError whenever any error happens,
and the also checks for PageError to decide if to call error handling.
This leads to very unclear responsibility for cleaning up on errors.
In the VM and generic writeback helpers the basic idea is that once
I/O is fired off all error handling responsibility is delegated to the
end I/O handler.  But if that end I/O handler sets the PageError bit,
and the submitter checks it, the bit could in some cases leak into the
submission context for fast enough I/O.

Fix this by simply not checking PageError and just using the local
ret variable to check for submission errors.  This also fundamentally
solves the long problem documented in a comment in __extent_writepage
by never leaking the error bit into the submission context.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-27 08:56:46 +02:00
David Sterba
689f5fbd89 btrfs: add xxhash to fast checksum implementations
[ Upstream commit efcfcbc6a3 ]

The implementation of XXHASH is now CPU only but still fast enough to be
considered for the synchronous checksumming, like non-generic crc32c.

A userspace benchmark comparing it to various implementations (patched
hash-speedtest from btrfs-progs):

  Block size:     4096
  Iterations:     1000000
  Implementation: builtin
  Units:          CPU cycles

	NULL-NOP: cycles:     73384294, cycles/i       73
     NULL-MEMCPY: cycles:    228033868, cycles/i      228,    61664.320 MiB/s
      CRC32C-ref: cycles:  24758559416, cycles/i    24758,      567.950 MiB/s
       CRC32C-NI: cycles:   1194350470, cycles/i     1194,    11773.433 MiB/s
  CRC32C-ADLERSW: cycles:   6150186216, cycles/i     6150,     2286.372 MiB/s
  CRC32C-ADLERHW: cycles:    626979180, cycles/i      626,    22427.453 MiB/s
      CRC32C-PCL: cycles:    466746732, cycles/i      466,    30126.699 MiB/s
	  XXHASH: cycles:    860656400, cycles/i      860,    16338.188 MiB/s

Comparing purely software implementation (ref), current outdated
accelerated using crc32q instruction (NI), optimized implementations by
M. Adler (https://stackoverflow.com/questions/17645167/implementing-sse-4-2s-crc32c-in-software/17646775#17646775)
and the best one that was taken from kernel using the PCLMULQDQ
instruction (PCL).

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-27 08:56:46 +02:00
Josef Bacik
72efe5d448 btrfs: fix race between balance and cancel/pause
commit b19c98f237 upstream.

Syzbot reported a panic that looks like this:

  assertion failed: fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED, in fs/btrfs/ioctl.c:465
  ------------[ cut here ]------------
  kernel BUG at fs/btrfs/messages.c:259!
  RIP: 0010:btrfs_assertfail+0x2c/0x30 fs/btrfs/messages.c:259
  Call Trace:
   <TASK>
   btrfs_exclop_balance fs/btrfs/ioctl.c:465 [inline]
   btrfs_ioctl_balance fs/btrfs/ioctl.c:3564 [inline]
   btrfs_ioctl+0x531e/0x5b30 fs/btrfs/ioctl.c:4632
   vfs_ioctl fs/ioctl.c:51 [inline]
   __do_sys_ioctl fs/ioctl.c:870 [inline]
   __se_sys_ioctl fs/ioctl.c:856 [inline]
   __x64_sys_ioctl+0x197/0x210 fs/ioctl.c:856
   do_syscall_x64 arch/x86/entry/common.c:50 [inline]
   do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
   entry_SYSCALL_64_after_hwframe+0x63/0xcd

The reproducer is running a balance and a cancel or pause in parallel.
The way balance finishes is a bit wonky, if we were paused we need to
save the balance_ctl in the fs_info, but clear it otherwise and cleanup.
However we rely on the return values being specific errors, or having a
cancel request or no pause request.  If balance completes and returns 0,
but we have a pause or cancel request we won't do the appropriate
cleanup, and then the next time we try to start a balance we'll trip
this ASSERT.

The error handling is just wrong here, we always want to clean up,
unless we got -ECANCELLED and we set the appropriate pause flag in the
exclusive op.  With this patch the reproducer ran for an hour without
tripping, previously it would trip in less than a few minutes.

Reported-by: syzbot+c0f3acf145cb465426d5@syzkaller.appspotmail.com
CC: stable@vger.kernel.org # 6.1+
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-27 08:56:35 +02:00
Filipe Manana
cca627afb4 btrfs: zoned: fix memory leak after finding block group with super blocks
commit f1a07c2b4e upstream.

At exclude_super_stripes(), if we happen to find a block group that has
super blocks mapped to it and we are on a zoned filesystem, we error out
as this is not supposed to happen, indicating either a bug or maybe some
memory corruption for example. However we are exiting the function without
freeing the memory allocated for the logical address of the super blocks.
Fix this by freeing the logical address.

Fixes: 12659251ca ("btrfs: implement log-structured superblock for ZONED mode")
CC: stable@vger.kernel.org # 5.10+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-27 08:56:34 +02:00
Filipe Manana
40150056dc btrfs: fix double iput() on inode after an error during orphan cleanup
commit b777d279ff upstream.

At btrfs_orphan_cleanup(), if we were able to find the inode, we do an
iput() on the inode, then if btrfs_drop_verity_items() succeeds and then
either btrfs_start_transaction() or btrfs_del_orphan_item() fail, we do
another iput() in the respective error paths, resulting in an extra iput()
on the inode.

Fix this by setting inode to NULL after the first iput(), as iput()
ignores a NULL inode pointer argument.

Fixes: a13bb2c038 ("btrfs: add missing iputs on orphan cleanup failure")
CC: stable@vger.kernel.org # 6.4
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-27 08:56:34 +02:00
Josef Bacik
a5880e69cf btrfs: set_page_extent_mapped after read_folio in btrfs_cont_expand
commit 17b17fcd6d upstream.

While trying to get the subpage blocksize tests running, I hit the
following panic on generic/476

  assertion failed: PagePrivate(page) && page->private, in fs/btrfs/subpage.c:229
  kernel BUG at fs/btrfs/subpage.c:229!
  Internal error: Oops - BUG: 00000000f2000800 [#1] SMP
  CPU: 1 PID: 1453 Comm: fsstress Not tainted 6.4.0-rc7+ #12
  Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20230301gitf80f052277c8-26.fc38 03/01/2023
  pstate: 61400005 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
  pc : btrfs_subpage_assert+0xbc/0xf0
  lr : btrfs_subpage_assert+0xbc/0xf0
  Call trace:
   btrfs_subpage_assert+0xbc/0xf0
   btrfs_subpage_clear_checked+0x38/0xc0
   btrfs_page_clear_checked+0x48/0x98
   btrfs_truncate_block+0x5d0/0x6a8
   btrfs_cont_expand+0x5c/0x528
   btrfs_write_check.isra.0+0xf8/0x150
   btrfs_buffered_write+0xb4/0x760
   btrfs_do_write_iter+0x2f8/0x4b0
   btrfs_file_write_iter+0x1c/0x30
   do_iter_readv_writev+0xc8/0x158
   do_iter_write+0x9c/0x210
   vfs_iter_write+0x24/0x40
   iter_file_splice_write+0x224/0x390
   direct_splice_actor+0x38/0x68
   splice_direct_to_actor+0x12c/0x260
   do_splice_direct+0x90/0xe8
   generic_copy_file_range+0x50/0x90
   vfs_copy_file_range+0x29c/0x470
   __arm64_sys_copy_file_range+0xcc/0x498
   invoke_syscall.constprop.0+0x80/0xd8
   do_el0_svc+0x6c/0x168
   el0_svc+0x50/0x1b0
   el0t_64_sync_handler+0x114/0x120
   el0t_64_sync+0x194/0x198

This happens because during btrfs_cont_expand we'll get a page, set it
as mapped, and if it's not Uptodate we'll read it.  However between the
read and re-locking the page we could have called release_folio() on the
page, but left the page in the file mapping.  release_folio() can clear
the page private, and thus further down we blow up when we go to modify
the subpage bits.

Fix this by putting the set_page_extent_mapped() after the read.  This
is safe because read_folio() will call set_page_extent_mapped() before
it does the read, and then if we clear page private but leave it on the
mapping we're completely safe re-setting set_page_extent_mapped().  With
this patch I can now run generic/476 without panicing.

CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-27 08:56:34 +02:00
Qu Wenruo
a981a8b5d3 btrfs: raid56: always verify the P/Q contents for scrub
commit 486c737f7f upstream.

[REGRESSION]
Commit 75b4703329 ("btrfs: raid56: migrate recovery and scrub recovery
path to use error_bitmap") changed the behavior of scrub_rbio().

Initially if we have no error reading the raid bio, we will assign
@need_check to true, then finish_parity_scrub() would later verify the
content of P/Q stripes before writeback.

But after that commit we never verify the content of P/Q stripes and
just writeback them.

This can lead to unrepaired P/Q stripes during scrub, or already
corrupted P/Q copied to the dev-replace target.

[FIX]
The situation is more complex than the regression, in fact the initial
behavior is not 100% correct either.

If we have the following rare case, it can still lead to the same
problem using the old behavior:

		0	16K	32K	48K	64K
	Data 1:	|IIIIIII|                       |
	Data 2:	|				|
	Parity:	|	|CCCCCCC|		|

Where "I" means IO error, "C" means corruption.

In the above case, we're scrubbing the parity stripe, then read out all
the contents of Data 1, Data 2, Parity stripes.

But found IO error in Data 1, which leads to rebuild using Data 2 and
Parity and got the correct data.

In that case, we would not verify if the Parity is correct for range
[16K, 32K).

So here we have to always verify the content of Parity no matter if we
did recovery or not.

This patch would remove the @need_check parameter of
finish_parity_scrub() completely, and would always do the P/Q
verification before writeback.

Fixes: 75b4703329 ("btrfs: raid56: migrate recovery and scrub recovery path to use error_bitmap")
CC: stable@vger.kernel.org # 6.2+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-27 08:56:34 +02:00
Filipe Manana
62dd82bc7a btrfs: fix warning when putting transaction with qgroups enabled after abort
commit aa84ce8a78 upstream.

If we have a transaction abort with qgroups enabled we get a warning
triggered when doing the final put on the transaction, like this:

  [552.6789] ------------[ cut here ]------------
  [552.6815] WARNING: CPU: 4 PID: 81745 at fs/btrfs/transaction.c:144 btrfs_put_transaction+0x123/0x130 [btrfs]
  [552.6817] Modules linked in: btrfs blake2b_generic xor (...)
  [552.6819] CPU: 4 PID: 81745 Comm: btrfs-transacti Tainted: G        W          6.4.0-rc6-btrfs-next-134+ #1
  [552.6819] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014
  [552.6819] RIP: 0010:btrfs_put_transaction+0x123/0x130 [btrfs]
  [552.6821] Code: bd a0 01 00 (...)
  [552.6821] RSP: 0018:ffffa168c0527e28 EFLAGS: 00010286
  [552.6821] RAX: ffff936042caed00 RBX: ffff93604a3eb448 RCX: 0000000000000000
  [552.6821] RDX: ffff93606421b028 RSI: ffffffff92ff0878 RDI: ffff93606421b010
  [552.6821] RBP: ffff93606421b000 R08: 0000000000000000 R09: ffffa168c0d07c20
  [552.6821] R10: 0000000000000000 R11: ffff93608dc52950 R12: ffffa168c0527e70
  [552.6821] R13: ffff93606421b000 R14: ffff93604a3eb420 R15: ffff93606421b028
  [552.6821] FS:  0000000000000000(0000) GS:ffff93675fb00000(0000) knlGS:0000000000000000
  [552.6821] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [552.6821] CR2: 0000558ad262b000 CR3: 000000014feda005 CR4: 0000000000370ee0
  [552.6822] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [552.6822] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [552.6822] Call Trace:
  [552.6822]  <TASK>
  [552.6822]  ? __warn+0x80/0x130
  [552.6822]  ? btrfs_put_transaction+0x123/0x130 [btrfs]
  [552.6824]  ? report_bug+0x1f4/0x200
  [552.6824]  ? handle_bug+0x42/0x70
  [552.6824]  ? exc_invalid_op+0x14/0x70
  [552.6824]  ? asm_exc_invalid_op+0x16/0x20
  [552.6824]  ? btrfs_put_transaction+0x123/0x130 [btrfs]
  [552.6826]  btrfs_cleanup_transaction+0xe7/0x5e0 [btrfs]
  [552.6828]  ? _raw_spin_unlock_irqrestore+0x23/0x40
  [552.6828]  ? try_to_wake_up+0x94/0x5e0
  [552.6828]  ? __pfx_process_timeout+0x10/0x10
  [552.6828]  transaction_kthread+0x103/0x1d0 [btrfs]
  [552.6830]  ? __pfx_transaction_kthread+0x10/0x10 [btrfs]
  [552.6832]  kthread+0xee/0x120
  [552.6832]  ? __pfx_kthread+0x10/0x10
  [552.6832]  ret_from_fork+0x29/0x50
  [552.6832]  </TASK>
  [552.6832] ---[ end trace 0000000000000000 ]---

This corresponds to this line of code:

  void btrfs_put_transaction(struct btrfs_transaction *transaction)
  {
      (...)
          WARN_ON(!RB_EMPTY_ROOT(
                          &transaction->delayed_refs.dirty_extent_root));
      (...)
  }

The warning happens because btrfs_qgroup_destroy_extent_records(), called
in the transaction abort path, we free all entries from the rbtree
"dirty_extent_root" with rbtree_postorder_for_each_entry_safe(), but we
don't actually empty the rbtree - it's still pointing to nodes that were
freed.

So set the rbtree's root node to NULL to avoid this warning (assign
RB_ROOT).

Fixes: 81f7eb00ff ("btrfs: destroy qgroup extent records on transaction abort")
CC: stable@vger.kernel.org # 5.10+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-27 08:56:33 +02:00
Filipe Manana
a21a43e433 btrfs: fix iput() on error pointer after error during orphan cleanup
commit cbaee87f2e upstream.

At btrfs_orphan_cleanup(), if we can't find an inode (btrfs_iget() returns
an -ENOENT error pointer), we proceed with 'ret' set to -ENOENT and the
inode pointer set to ERR_PTR(-ENOENT). Later when we proceed to the body
of the following if statement:

    if (ret == -ENOENT || inode->i_nlink) {
        (...)
        trans = btrfs_start_transaction(root, 1);
        if (IS_ERR(trans)) {
            ret = PTR_ERR(trans);
            iput(inode);
            goto out;
        }
        (...)
        ret = btrfs_del_orphan_item(trans, root,
                                    found_key.objectid);
        btrfs_end_transaction(trans);
        if (ret) {
            iput(inode);
            goto out;
        }
        continue;
    }

If we get an error from btrfs_start_transaction() or from the call to
btrfs_del_orphan_item() we end calling iput() against an inode pointer
that has a value of ERR_PTR(-ENOENT), resulting in a crash with the
following trace:

  [876.667] BUG: kernel NULL pointer dereference, address: 0000000000000096
  [876.667] #PF: supervisor read access in kernel mode
  [876.667] #PF: error_code(0x0000) - not-present page
  [876.667] PGD 0 P4D 0
  [876.668] Oops: 0000 [#1] PREEMPT SMP PTI
  [876.668] CPU: 0 PID: 2356187 Comm: mount Tainted: G        W          6.4.0-rc6-btrfs-next-134+ #1
  [876.668] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014
  [876.668] RIP: 0010:iput+0xa/0x20
  [876.668] Code: ff ff ff 66 (...)
  [876.669] RSP: 0018:ffffafa9c0c9f9d0 EFLAGS: 00010282
  [876.669] RAX: ffffffffffffffe4 RBX: 000000000009453b RCX: 0000000000000000
  [876.669] RDX: 0000000000000001 RSI: ffffafa9c0c9f930 RDI: fffffffffffffffe
  [876.669] RBP: ffff95c612f3b800 R08: 0000000000000001 R09: ffffffffffffffe4
  [876.670] R10: 00018f2a71010000 R11: 000000000ead96e3 R12: ffff95cb7d6909a0
  [876.670] R13: fffffffffffffffe R14: ffff95c60f477000 R15: 00000000ffffffe4
  [876.670] FS:  00007f5fbe30a840(0000) GS:ffff95ccdfa00000(0000) knlGS:0000000000000000
  [876.670] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [876.671] CR2: 0000000000000096 CR3: 000000055e9f6004 CR4: 0000000000370ef0
  [876.671] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [876.671] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [876.672] Call Trace:
  [876.744]  <TASK>
  [876.744]  ? __die_body+0x1b/0x60
  [876.744]  ? page_fault_oops+0x15d/0x450
  [876.745]  ? __kmem_cache_alloc_node+0x47/0x410
  [876.745]  ? do_user_addr_fault+0x65/0x8a0
  [876.745]  ? exc_page_fault+0x74/0x170
  [876.746]  ? asm_exc_page_fault+0x22/0x30
  [876.746]  ? iput+0xa/0x20
  [876.746]  btrfs_orphan_cleanup+0x221/0x330 [btrfs]
  [876.746]  btrfs_lookup_dentry+0x58f/0x5f0 [btrfs]
  [876.747]  btrfs_lookup+0xe/0x30 [btrfs]
  [876.747]  __lookup_slow+0x82/0x130
  [876.785]  walk_component+0xe5/0x160
  [876.786]  path_lookupat.isra.0+0x6e/0x150
  [876.786]  filename_lookup+0xcf/0x1a0
  [876.786]  ? mod_objcg_state+0xd2/0x360
  [876.786]  ? obj_cgroup_charge+0xf5/0x110
  [876.787]  ? should_failslab+0xa/0x20
  [876.787]  ? kmem_cache_alloc+0x47/0x450
  [876.787]  vfs_path_lookup+0x51/0x90
  [876.788]  mount_subtree+0x8d/0x130
  [876.788]  btrfs_mount+0x149/0x410 [btrfs]
  [876.788]  ? __kmem_cache_alloc_node+0x47/0x410
  [876.788]  ? vfs_parse_fs_param+0xc0/0x110
  [876.789]  legacy_get_tree+0x24/0x50
  [876.834]  vfs_get_tree+0x22/0xd0
  [876.852]  path_mount+0x2d8/0x9c0
  [876.852]  do_mount+0x79/0x90
  [876.852]  __x64_sys_mount+0x8e/0xd0
  [876.853]  do_syscall_64+0x38/0x90
  [876.899]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
  [876.958] RIP: 0033:0x7f5fbe50b76a
  [876.959] Code: 48 8b 0d a9 (...)
  [876.959] RSP: 002b:00007fff01925798 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
  [876.959] RAX: ffffffffffffffda RBX: 00007f5fbe694264 RCX: 00007f5fbe50b76a
  [876.960] RDX: 0000561bde6c8720 RSI: 0000561bde6bdec0 RDI: 0000561bde6c31a0
  [876.960] RBP: 0000561bde6bdc70 R08: 0000000000000000 R09: 0000000000000001
  [876.960] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
  [876.960] R13: 0000561bde6c31a0 R14: 0000561bde6c8720 R15: 0000561bde6bdc70
  [876.960]  </TASK>

So fix this by setting 'inode' to NULL whenever we get an error from
btrfs_iget(), and to make the code simpler, stop testing for 'ret' being
-ENOENT to check if we have an inode - instead test for 'inode' being NULL
or not. Having a NULL 'inode' prevents any iput() call from crashing, as
iput() ignores NULL inode pointers. Also, stop testing for a NULL return
value from btrfs_iget() with PTR_ERR_OR_ZERO(), because btrfs_iget() never
returns NULL - in case an inode is not found, it returns ERR_PTR(-ENOENT),
and in case of memory allocation failure, it returns ERR_PTR(-ENOMEM).
We also don't need the extra iput() calls on the error branches for the
btrfs_start_transaction() and btrfs_del_orphan_item() calls, as we have
already called iput() before, so remove them.

Fixes: a13bb2c038 ("btrfs: add missing iputs on orphan cleanup failure")
CC: stable@vger.kernel.org # 6.4
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-27 08:56:33 +02:00
Filipe Manana
82270e7f28 btrfs: do not BUG_ON() on tree mod log failure at __btrfs_cow_block()
commit 40b0a74938 upstream.

At __btrfs_cow_block(), instead of doing a BUG_ON() in case we fail to
record a tree mod log root insertion operation, do a transaction abort
instead. There's really no need for the BUG_ON(), we can properly
release all resources in this context and turn the filesystem to RO mode
and in an error state instead.

CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-19 16:36:57 +02:00
Filipe Manana
796eb12aa5 btrfs: fix extent buffer leak after tree mod log failure at split_node()
commit ede600e497 upstream.

At split_node(), if we fail to log the tree mod log copy operation, we
return without unlocking the split extent buffer we just allocated and
without decrementing the reference we own on it. Fix this by unlocking
it and decrementing the ref count before returning.

Fixes: 5de865eebb ("Btrfs: fix tree mod logging")
CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-19 16:36:57 +02:00
Filipe Manana
6df630a1e3 btrfs: add missing error handling when logging operation while COWing extent buffer
commit d09c51521f upstream.

When COWing an extent buffer that is not the root node, we need to log in
the tree mod log that we replaced a pointer in the parent node, otherwise
a tree mod log user doing a search on the b+tree can return incorrect
results (that miss something). We are doing the call to
btrfs_tree_mod_log_insert_key() but we totally ignore its return value.

So fix this by adding the missing error handling, resulting in a
transaction abort and freeing the COWed extent buffer.

Fixes: f230475e62 ("Btrfs: put all block modifications into the tree mod log")
CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-19 16:36:57 +02:00
Filipe Manana
a5cdc4012e btrfs: fix race when deleting quota root from the dirty cow roots list
commit b31cb5a6eb upstream.

When disabling quotas we are deleting the quota root from the list
fs_info->dirty_cowonly_roots without taking the lock that protects it,
which is struct btrfs_fs_info::trans_lock. This unsynchronized list
manipulation may cause chaos if there's another concurrent manipulation
of this list, such as when adding a root to it with
ctree.c:add_root_to_dirty_list().

This can result in all sorts of weird failures caused by a race, such as
the following crash:

  [337571.278245] general protection fault, probably for non-canonical address 0xdead000000000108: 0000 [#1] PREEMPT SMP PTI
  [337571.278933] CPU: 1 PID: 115447 Comm: btrfs Tainted: G        W          6.4.0-rc6-btrfs-next-134+ #1
  [337571.279153] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
  [337571.279572] RIP: 0010:commit_cowonly_roots+0x11f/0x250 [btrfs]
  [337571.279928] Code: 85 38 06 00 (...)
  [337571.280363] RSP: 0018:ffff9f63446efba0 EFLAGS: 00010206
  [337571.280582] RAX: ffff942d98ec2638 RBX: ffff9430b82b4c30 RCX: 0000000449e1c000
  [337571.280798] RDX: dead000000000100 RSI: ffff9430021e4900 RDI: 0000000000036070
  [337571.281015] RBP: ffff942d98ec2000 R08: ffff942d98ec2000 R09: 000000000000015b
  [337571.281254] R10: 0000000000000009 R11: 0000000000000001 R12: ffff942fe8fbf600
  [337571.281476] R13: ffff942dabe23040 R14: ffff942dabe20800 R15: ffff942d92cf3b48
  [337571.281723] FS:  00007f478adb7340(0000) GS:ffff94349fa40000(0000) knlGS:0000000000000000
  [337571.281950] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [337571.282184] CR2: 00007f478ab9a3d5 CR3: 000000001e02c001 CR4: 0000000000370ee0
  [337571.282416] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [337571.282647] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [337571.282874] Call Trace:
  [337571.283101]  <TASK>
  [337571.283327]  ? __die_body+0x1b/0x60
  [337571.283570]  ? die_addr+0x39/0x60
  [337571.283796]  ? exc_general_protection+0x22e/0x430
  [337571.284022]  ? asm_exc_general_protection+0x22/0x30
  [337571.284251]  ? commit_cowonly_roots+0x11f/0x250 [btrfs]
  [337571.284531]  btrfs_commit_transaction+0x42e/0xf90 [btrfs]
  [337571.284803]  ? _raw_spin_unlock+0x15/0x30
  [337571.285031]  ? release_extent_buffer+0x103/0x130 [btrfs]
  [337571.285305]  reset_balance_state+0x152/0x1b0 [btrfs]
  [337571.285578]  btrfs_balance+0xa50/0x11e0 [btrfs]
  [337571.285864]  ? __kmem_cache_alloc_node+0x14a/0x410
  [337571.286086]  btrfs_ioctl+0x249a/0x3320 [btrfs]
  [337571.286358]  ? mod_objcg_state+0xd2/0x360
  [337571.286577]  ? refill_obj_stock+0xb0/0x160
  [337571.286798]  ? seq_release+0x25/0x30
  [337571.287016]  ? __rseq_handle_notify_resume+0x3ba/0x4b0
  [337571.287235]  ? percpu_counter_add_batch+0x2e/0xa0
  [337571.287455]  ? __x64_sys_ioctl+0x88/0xc0
  [337571.287675]  __x64_sys_ioctl+0x88/0xc0
  [337571.287901]  do_syscall_64+0x38/0x90
  [337571.288126]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
  [337571.288352] RIP: 0033:0x7f478aaffe9b

So fix this by locking struct btrfs_fs_info::trans_lock before deleting
the quota root from that list.

Fixes: bed92eae26 ("Btrfs: qgroup implementation and prototypes")
CC: stable@vger.kernel.org # 4.14+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-19 16:36:57 +02:00
Naohiro Aota
6c65062f66 btrfs: reinsert BGs failed to reclaim
commit 7e27180994 upstream.

The reclaim process can temporarily fail. For example, if the space is
getting tight, it fails to make the block group read-only. If there are no
further writes on that block group, the block group will never get back to
the reclaim list, and the BG never gets reclaimed. In a certain workload,
we can leave many such block groups never reclaimed.

So, let's get it back to the list and give it a chance to be reclaimed.

Fixes: 18bb8bbf13 ("btrfs: zoned: automatically reclaim zones")
CC: stable@vger.kernel.org # 5.15+
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-19 16:36:57 +02:00
David Sterba
7b063701b5 btrfs: add block-group tree to lockdep classes
commit 1a1b0e729d upstream.

The block group tree was not present among the lockdep classes. We could
get potentially lockdep warnings but so far none has been seen, also
because block-group-tree is a relatively new feature.

CC: stable@vger.kernel.org # 6.1+
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-19 16:36:57 +02:00
Naohiro Aota
f61029274c btrfs: bail out reclaim process if filesystem is read-only
commit 93463ff7b5 upstream.

When a filesystem is read-only, we cannot reclaim a block group as it
cannot rewrite the data. Just bail out in that case.

Note that it can drop block groups in this case. As we did
sb_start_write(), read-only filesystem means we got a fatal error and
forced read-only. There is no chance to reclaim them again.

Fixes: 18bb8bbf13 ("btrfs: zoned: automatically reclaim zones")
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Filipe Manana <fdmanana@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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-19 16:36:56 +02:00
Naohiro Aota
9d9586ef1a btrfs: delete unused BGs while reclaiming BGs
commit 3ed01616ba upstream.

The reclaiming process only starts after the filesystem volumes are
allocated to a certain level (75% by default). Thus, the list of
reclaiming target block groups can build up so huge at the time the
reclaim process kicks in. On a test run, there were over 1000 BGs in the
reclaim list.

As the reclaim involves rewriting the data, it takes really long time to
reclaim the BGs. While the reclaim is running, btrfs_delete_unused_bgs()
won't proceed because the reclaim side is holding
fs_info->reclaim_bgs_lock. As a result, we will have a large number of
unused BGs kept in the unused list. On my test run, I got 1057 unused BGs.

Since deleting a block group is relatively easy and fast work, we can call
btrfs_delete_unused_bgs() while it reclaims BGs, to avoid building up
unused BGs.

Fixes: 18bb8bbf13 ("btrfs: zoned: automatically reclaim zones")
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Filipe Manana <fdmanana@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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-19 16:36:56 +02:00
Boris Burkov
987cf64973 btrfs: warn on invalid slot in tree mod log rewind
commit 95c8e349d8 upstream.

The way that tree mod log tracks the ultimate length of the eb, the
variable 'n', eventually turns up the correct value, but at intermediate
steps during the rewind, n can be inaccurate as a representation of the
end of the eb. For example, it doesn't get updated on move rewinds, and
it does get updated for add/remove in the middle of the eb.

To detect cases with invalid moves, introduce a separate variable called
max_slot which tries to track the maximum valid slot in the rewind eb.
We can then warn if we do a move whose src range goes beyond the max
valid slot.

There is a commented caveat that it is possible to have this value be an
overestimate due to the challenge of properly handling 'add' operations
in the middle of the eb, but in practice it doesn't cause enough of a
problem to throw out the max idea in favor of tracking every valid slot.

CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-19 16:36:56 +02:00
Boris Burkov
11f14402fe btrfs: insert tree mod log move in push_node_left
commit 5cead5422a upstream.

There is a fairly unlikely race condition in tree mod log rewind that
can result in a kernel panic which has the following trace:

  [530.569] BTRFS critical (device sda3): unable to find logical 0 length 4096
  [530.585] BTRFS critical (device sda3): unable to find logical 0 length 4096
  [530.602] BUG: kernel NULL pointer dereference, address: 0000000000000002
  [530.618] #PF: supervisor read access in kernel mode
  [530.629] #PF: error_code(0x0000) - not-present page
  [530.641] PGD 0 P4D 0
  [530.647] Oops: 0000 [#1] SMP
  [530.654] CPU: 30 PID: 398973 Comm: below Kdump: loaded Tainted: G S         O  K   5.12.0-0_fbk13_clang_7455_gb24de3bdb045 #1
  [530.680] Hardware name: Quanta Mono Lake-M.2 SATA 1HY9U9Z001G/Mono Lake-M.2 SATA, BIOS F20_3A15 08/16/2017
  [530.703] RIP: 0010:__btrfs_map_block+0xaa/0xd00
  [530.755] RSP: 0018:ffffc9002c2f7600 EFLAGS: 00010246
  [530.767] RAX: ffffffffffffffea RBX: ffff888292e41000 RCX: f2702d8b8be15100
  [530.784] RDX: ffff88885fda6fb8 RSI: ffff88885fd973c8 RDI: ffff88885fd973c8
  [530.800] RBP: ffff888292e410d0 R08: ffffffff82fd7fd0 R09: 00000000fffeffff
  [530.816] R10: ffffffff82e57fd0 R11: ffffffff82e57d70 R12: 0000000000000000
  [530.832] R13: 0000000000001000 R14: 0000000000001000 R15: ffffc9002c2f76f0
  [530.848] FS:  00007f38d64af000(0000) GS:ffff88885fd80000(0000) knlGS:0000000000000000
  [530.866] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [530.880] CR2: 0000000000000002 CR3: 00000002b6770004 CR4: 00000000003706e0
  [530.896] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [530.912] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [530.928] Call Trace:
  [530.934]  ? btrfs_printk+0x13b/0x18c
  [530.943]  ? btrfs_bio_counter_inc_blocked+0x3d/0x130
  [530.955]  btrfs_map_bio+0x75/0x330
  [530.963]  ? kmem_cache_alloc+0x12a/0x2d0
  [530.973]  ? btrfs_submit_metadata_bio+0x63/0x100
  [530.984]  btrfs_submit_metadata_bio+0xa4/0x100
  [530.995]  submit_extent_page+0x30f/0x360
  [531.004]  read_extent_buffer_pages+0x49e/0x6d0
  [531.015]  ? submit_extent_page+0x360/0x360
  [531.025]  btree_read_extent_buffer_pages+0x5f/0x150
  [531.037]  read_tree_block+0x37/0x60
  [531.046]  read_block_for_search+0x18b/0x410
  [531.056]  btrfs_search_old_slot+0x198/0x2f0
  [531.066]  resolve_indirect_ref+0xfe/0x6f0
  [531.076]  ? ulist_alloc+0x31/0x60
  [531.084]  ? kmem_cache_alloc_trace+0x12e/0x2b0
  [531.095]  find_parent_nodes+0x720/0x1830
  [531.105]  ? ulist_alloc+0x10/0x60
  [531.113]  iterate_extent_inodes+0xea/0x370
  [531.123]  ? btrfs_previous_extent_item+0x8f/0x110
  [531.134]  ? btrfs_search_path_in_tree+0x240/0x240
  [531.146]  iterate_inodes_from_logical+0x98/0xd0
  [531.157]  ? btrfs_search_path_in_tree+0x240/0x240
  [531.168]  btrfs_ioctl_logical_to_ino+0xd9/0x180
  [531.179]  btrfs_ioctl+0xe2/0x2eb0

This occurs when logical inode resolution takes a tree mod log sequence
number, and then while backref walking hits a rewind on a busy node
which has the following sequence of tree mod log operations (numbers
filled in from a specific example, but they are somewhat arbitrary)

  REMOVE_WHILE_FREEING slot 532
  REMOVE_WHILE_FREEING slot 531
  REMOVE_WHILE_FREEING slot 530
  ...
  REMOVE_WHILE_FREEING slot 0
  REMOVE slot 455
  REMOVE slot 454
  REMOVE slot 453
  ...
  REMOVE slot 0
  ADD slot 455
  ADD slot 454
  ADD slot 453
  ...
  ADD slot 0
  MOVE src slot 0 -> dst slot 456 nritems 533
  REMOVE slot 455
  REMOVE slot 454
  REMOVE slot 453
  ...
  REMOVE slot 0

When this sequence gets applied via btrfs_tree_mod_log_rewind, it
allocates a fresh rewind eb, and first inserts the correct key info for
the 533 elements, then overwrites the first 456 of them, then decrements
the count by 456 via the add ops, then rewinds the move by doing a
memmove from 456:988->0:532. We have never written anything past 532, so
that memmove writes garbage into the 0:532 range. In practice, this
results in a lot of fully 0 keys. The rewind then puts valid keys into
slots 0:455 with the last removes, but 456:532 are still invalid.

When search_old_slot uses this eb, if it uses one of those invalid
slots, it can then read the extent buffer and issue a bio for offset 0
which ultimately panics looking up extent mappings.

This bad tree mod log sequence gets generated when the node balancing
code happens to do a balance_node_right followed by a push_node_left
while logging in the tree mod log. Illustrated for ebs L and R (left and
right):

	L                 R
  start:
  [XXX|YYY|...]      [ZZZ|...|...]
  balance_node_right:
  [XXX|YYY|...]      [...|ZZZ|...] move Z to make room for Y
  [XXX|...|...]      [YYY|ZZZ|...] copy Y from L to R
  push_node_left:
  [XXX|YYY|...]      [...|ZZZ|...] copy Y from R to L
  [XXX|YYY|...]      [ZZZ|...|...] move Z into emptied space (NOT LOGGED!)

This is because balance_node_right logs a move, but push_node_left
explicitly doesn't. That is because logging the move would remove the
overwritten src < dst range in the right eb, which was already logged
when we called btrfs_tree_mod_log_eb_copy. The correct sequence would
include a move from 456:988 to 0:532 after remove 0:455 and before
removing 0:532. Reversing that sequence would entail creating keys for
0:532, then moving those keys out to 456:988, then creating more keys
for 0:455.

i.e.,

  REMOVE_WHILE_FREEING slot 532
  REMOVE_WHILE_FREEING slot 531
  REMOVE_WHILE_FREEING slot 530
  ...
  REMOVE_WHILE_FREEING slot 0
  MOVE src slot 456 -> dst slot 0 nritems 533
  REMOVE slot 455
  REMOVE slot 454
  REMOVE slot 453
  ...
  REMOVE slot 0
  ADD slot 455
  ADD slot 454
  ADD slot 453
  ...
  ADD slot 0
  MOVE src slot 0 -> dst slot 456 nritems 533
  REMOVE slot 455
  REMOVE slot 454
  REMOVE slot 453
  ...
  REMOVE slot 0

Fix this to log the move but avoid the double remove by putting all the
logging logic in btrfs_tree_mod_log_eb_copy which has enough information
to detect these cases and properly log moves, removes, and adds. Leave
btrfs_tree_mod_log_insert_move to handle insert_ptr and delete_ptr's
tree mod logging.

(Un)fortunately, this is quite difficult to reproduce, and I was only
able to reproduce it by adding sleeps in btrfs_search_old_slot that
would encourage more log rewinding during ino_to_logical ioctls. I was
able to hit the warning in the previous patch in the series without the
fix quite quickly, but not after this patch.

CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-19 16:36:56 +02:00
Christoph Hellwig
1ea89213cd btrfs: fix dirty_metadata_bytes for redirtied buffers
commit f18cc97845 upstream.

dirty_metadata_bytes is decremented in both places that clear the dirty
bit in a buffer, but only incremented in btrfs_mark_buffer_dirty, which
means that a buffer that is redirtied using btrfs_redirty_list_add won't
be added to dirty_metadata_bytes, but it will be subtracted when written
out, leading an inconsistency in the counter.

Move the dirty_metadata_bytes from btrfs_mark_buffer_dirty into
set_extent_buffer_dirty to also account for the redirty case, and remove
the now unused set_extent_buffer_dirty return value.

Fixes: d3575156f6 ("btrfs: zoned: redirty released extent buffers")
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-19 16:36:56 +02:00
Matt Corallo
1b532748ba btrfs: add handling for RAID1C23/DUP to btrfs_reduce_alloc_profile
commit 160fe8f6fd upstream.

Callers of `btrfs_reduce_alloc_profile` expect it to return exactly
one allocation profile flag, and failing to do so may ultimately
result in a WARN_ON and remount-ro when allocating new blocks, like
the below transaction abort on 6.1.

`btrfs_reduce_alloc_profile` has two ways of determining the profile,
first it checks if a conversion balance is currently running and
uses the profile we're converting to. If no balance is currently
running, it returns the max-redundancy profile which at least one
block in the selected block group has.

This works by simply checking each known allocation profile bit in
redundancy order. However, `btrfs_reduce_alloc_profile` has not been
updated as new flags have been added - first with the `DUP` profile
and later with the RAID1C34 profiles.

Because of the way it checks, if we have blocks with different
profiles and at least one is known, that profile will be selected.
However, if none are known we may return a flag set with multiple
allocation profiles set.

This is currently only possible when a balance from one of the three
unhandled profiles to another of the unhandled profiles is canceled
after allocating at least one block using the new profile.

In that case, a transaction abort like the below will occur and the
filesystem will need to be mounted with -o skip_balance to get it
mounted rw again (but the balance cannot be resumed without a
similar abort).

  [770.648] ------------[ cut here ]------------
  [770.648] BTRFS: Transaction aborted (error -22)
  [770.648] WARNING: CPU: 43 PID: 1159593 at fs/btrfs/extent-tree.c:4122 find_free_extent+0x1d94/0x1e00 [btrfs]
  [770.648] CPU: 43 PID: 1159593 Comm: btrfs Tainted: G        W 6.1.0-0.deb11.7-powerpc64le #1  Debian 6.1.20-2~bpo11+1a~test
  [770.648] Hardware name: T2P9D01 REV 1.00 POWER9 0x4e1202 opal:skiboot-bc106a0 PowerNV
  [770.648] NIP:  c00800000f6784fc LR: c00800000f6784f8 CTR: c000000000d746c0
  [770.648] REGS: c000200089afe9a0 TRAP: 0700   Tainted: G        W (6.1.0-0.deb11.7-powerpc64le Debian 6.1.20-2~bpo11+1a~test)
  [770.648] MSR:  9000000002029033 <SF,HV,VEC,EE,ME,IR,DR,RI,LE>  CR: 28848282  XER: 20040000
  [770.648] CFAR: c000000000135110 IRQMASK: 0
	    GPR00: c00800000f6784f8 c000200089afec40 c00800000f7ea800 0000000000000026
	    GPR04: 00000001004820c2 c000200089afea00 c000200089afe9f8 0000000000000027
	    GPR08: c000200ffbfe7f98 c000000002127f90 ffffffffffffffd8 0000000026d6a6e8
	    GPR12: 0000000028848282 c000200fff7f3800 5deadbeef0000122 c00000002269d000
	    GPR16: c0002008c7797c40 c000200089afef17 0000000000000000 0000000000000000
	    GPR20: 0000000000000000 0000000000000001 c000200008bc5a98 0000000000000001
	    GPR24: 0000000000000000 c0000003c73088d0 c000200089afef17 c000000016d3a800
	    GPR28: c0000003c7308800 c00000002269d000 ffffffffffffffea 0000000000000001
  [770.648] NIP [c00800000f6784fc] find_free_extent+0x1d94/0x1e00 [btrfs]
  [770.648] LR [c00800000f6784f8] find_free_extent+0x1d90/0x1e00 [btrfs]
  [770.648] Call Trace:
  [770.648] [c000200089afec40] [c00800000f6784f8] find_free_extent+0x1d90/0x1e00 [btrfs] (unreliable)
  [770.648] [c000200089afed30] [c00800000f681398] btrfs_reserve_extent+0x1a0/0x2f0 [btrfs]
  [770.648] [c000200089afeea0] [c00800000f681bf0] btrfs_alloc_tree_block+0x108/0x670 [btrfs]
  [770.648] [c000200089afeff0] [c00800000f66bd68] __btrfs_cow_block+0x170/0x850 [btrfs]
  [770.648] [c000200089aff100] [c00800000f66c58c] btrfs_cow_block+0x144/0x288 [btrfs]
  [770.648] [c000200089aff1b0] [c00800000f67113c] btrfs_search_slot+0x6b4/0xcb0 [btrfs]
  [770.648] [c000200089aff2a0] [c00800000f679f60] lookup_inline_extent_backref+0x128/0x7c0 [btrfs]
  [770.648] [c000200089aff3b0] [c00800000f67b338] lookup_extent_backref+0x70/0x190 [btrfs]
  [770.648] [c000200089aff470] [c00800000f67b54c] __btrfs_free_extent+0xf4/0x1490 [btrfs]
  [770.648] [c000200089aff5a0] [c00800000f67d770] __btrfs_run_delayed_refs+0x328/0x1530 [btrfs]
  [770.648] [c000200089aff740] [c00800000f67ea2c] btrfs_run_delayed_refs+0xb4/0x3e0 [btrfs]
  [770.648] [c000200089aff800] [c00800000f699aa4] btrfs_commit_transaction+0x8c/0x12b0 [btrfs]
  [770.648] [c000200089aff8f0] [c00800000f6dc628] reset_balance_state+0x1c0/0x290 [btrfs]
  [770.648] [c000200089aff9a0] [c00800000f6e2f7c] btrfs_balance+0x1164/0x1500 [btrfs]
  [770.648] [c000200089affb40] [c00800000f6f8e4c] btrfs_ioctl+0x2b54/0x3100 [btrfs]
  [770.648] [c000200089affc80] [c00000000053be14] sys_ioctl+0x794/0x1310
  [770.648] [c000200089affd70] [c00000000002af98] system_call_exception+0x138/0x250
  [770.648] [c000200089affe10] [c00000000000c654] system_call_common+0xf4/0x258
  [770.648] --- interrupt: c00 at 0x7fff94126800
  [770.648] NIP:  00007fff94126800 LR: 0000000107e0b594 CTR: 0000000000000000
  [770.648] REGS: c000200089affe80 TRAP: 0c00   Tainted: G        W (6.1.0-0.deb11.7-powerpc64le Debian 6.1.20-2~bpo11+1a~test)
  [770.648] MSR:  900000000000d033 <SF,HV,EE,PR,ME,IR,DR,RI,LE>  CR: 24002848  XER: 00000000
  [770.648] IRQMASK: 0
	    GPR00: 0000000000000036 00007fffc9439da0 00007fff94217100 0000000000000003
	    GPR04: 00000000c4009420 00007fffc9439ee8 0000000000000000 0000000000000000
	    GPR08: 00000000803c7416 0000000000000000 0000000000000000 0000000000000000
	    GPR12: 0000000000000000 00007fff9467d120 0000000107e64c9c 0000000107e64d0a
	    GPR16: 0000000107e64d06 0000000107e64cf1 0000000107e64cc4 0000000107e64c73
	    GPR20: 0000000107e64c31 0000000107e64bf1 0000000107e64be7 0000000000000000
	    GPR24: 0000000000000000 00007fffc9439ee0 0000000000000003 0000000000000001
	    GPR28: 00007fffc943f713 0000000000000000 00007fffc9439ee8 0000000000000000
  [770.648] NIP [00007fff94126800] 0x7fff94126800
  [770.648] LR [0000000107e0b594] 0x107e0b594
  [770.648] --- interrupt: c00
  [770.648] Instruction dump:
  [770.648] 3b00ffe4 e8898828 481175f5 60000000 4bfff4fc 3be00000 4bfff570 3d220000
  [770.648] 7fc4f378 e8698830 4811cd95 e8410018 <0fe00000> f9c10060 f9e10068 fa010070
  [770.648] ---[ end trace 0000000000000000 ]---
  [770.648] BTRFS: error (device dm-2: state A) in find_free_extent_update_loop:4122: errno=-22 unknown
  [770.648] BTRFS info (device dm-2: state EA): forced readonly
  [770.648] BTRFS: error (device dm-2: state EA) in __btrfs_free_extent:3070: errno=-22 unknown
  [770.648] BTRFS error (device dm-2: state EA): failed to run delayed ref for logical 17838685708288 num_bytes 24576 type 184 action 2 ref_mod 1: -22
  [770.648] BTRFS: error (device dm-2: state EA) in btrfs_run_delayed_refs:2144: errno=-22 unknown
  [770.648] BTRFS: error (device dm-2: state EA) in reset_balance_state:3599: errno=-22 unknown

Fixes: 47e6f7423b ("btrfs: add support for 3-copy replication (raid1c3)")
Fixes: 8d6fac0087 ("btrfs: add support for 4-copy replication (raid1c4)")
CC: stable@vger.kernel.org # 5.10+
Signed-off-by: Matt Corallo <blnxfsl@bluematt.me>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-19 16:36:56 +02:00
Filipe Manana
532da3822a btrfs: do not BUG_ON() on tree mod log failure at balance_level()
commit 39020d8abc upstream.

At balance_level(), instead of doing a BUG_ON() in case we fail to record
tree mod log operations, do a transaction abort and return the error to
the callers. There's really no need for the BUG_ON() as we can release
all resources in this context, and we have to abort because other future
tree searches that use the tree mod log (btrfs_search_old_slot()) may get
inconsistent results if other operations modify the tree after that
failure and before the tree mod log based search.

CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-19 16:36:22 +02:00
Filipe Manana
8ce9139aea btrfs: fix race when deleting free space root from the dirty cow roots list
commit babebf023e upstream.

When deleting the free space tree we are deleting the free space root
from the list fs_info->dirty_cowonly_roots without taking the lock that
protects it, which is struct btrfs_fs_info::trans_lock.
This unsynchronized list manipulation may cause chaos if there's another
concurrent manipulation of this list, such as when adding a root to it
with ctree.c:add_root_to_dirty_list().

This can result in all sorts of weird failures caused by a race, such as
the following crash:

  [337571.278245] general protection fault, probably for non-canonical address 0xdead000000000108: 0000 [#1] PREEMPT SMP PTI
  [337571.278933] CPU: 1 PID: 115447 Comm: btrfs Tainted: G        W          6.4.0-rc6-btrfs-next-134+ #1
  [337571.279153] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
  [337571.279572] RIP: 0010:commit_cowonly_roots+0x11f/0x250 [btrfs]
  [337571.279928] Code: 85 38 06 00 (...)
  [337571.280363] RSP: 0018:ffff9f63446efba0 EFLAGS: 00010206
  [337571.280582] RAX: ffff942d98ec2638 RBX: ffff9430b82b4c30 RCX: 0000000449e1c000
  [337571.280798] RDX: dead000000000100 RSI: ffff9430021e4900 RDI: 0000000000036070
  [337571.281015] RBP: ffff942d98ec2000 R08: ffff942d98ec2000 R09: 000000000000015b
  [337571.281254] R10: 0000000000000009 R11: 0000000000000001 R12: ffff942fe8fbf600
  [337571.281476] R13: ffff942dabe23040 R14: ffff942dabe20800 R15: ffff942d92cf3b48
  [337571.281723] FS:  00007f478adb7340(0000) GS:ffff94349fa40000(0000) knlGS:0000000000000000
  [337571.281950] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [337571.282184] CR2: 00007f478ab9a3d5 CR3: 000000001e02c001 CR4: 0000000000370ee0
  [337571.282416] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [337571.282647] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [337571.282874] Call Trace:
  [337571.283101]  <TASK>
  [337571.283327]  ? __die_body+0x1b/0x60
  [337571.283570]  ? die_addr+0x39/0x60
  [337571.283796]  ? exc_general_protection+0x22e/0x430
  [337571.284022]  ? asm_exc_general_protection+0x22/0x30
  [337571.284251]  ? commit_cowonly_roots+0x11f/0x250 [btrfs]
  [337571.284531]  btrfs_commit_transaction+0x42e/0xf90 [btrfs]
  [337571.284803]  ? _raw_spin_unlock+0x15/0x30
  [337571.285031]  ? release_extent_buffer+0x103/0x130 [btrfs]
  [337571.285305]  reset_balance_state+0x152/0x1b0 [btrfs]
  [337571.285578]  btrfs_balance+0xa50/0x11e0 [btrfs]
  [337571.285864]  ? __kmem_cache_alloc_node+0x14a/0x410
  [337571.286086]  btrfs_ioctl+0x249a/0x3320 [btrfs]
  [337571.286358]  ? mod_objcg_state+0xd2/0x360
  [337571.286577]  ? refill_obj_stock+0xb0/0x160
  [337571.286798]  ? seq_release+0x25/0x30
  [337571.287016]  ? __rseq_handle_notify_resume+0x3ba/0x4b0
  [337571.287235]  ? percpu_counter_add_batch+0x2e/0xa0
  [337571.287455]  ? __x64_sys_ioctl+0x88/0xc0
  [337571.287675]  __x64_sys_ioctl+0x88/0xc0
  [337571.287901]  do_syscall_64+0x38/0x90
  [337571.288126]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
  [337571.288352] RIP: 0033:0x7f478aaffe9b

So fix this by locking struct btrfs_fs_info::trans_lock before deleting
the free space root from that list.

Fixes: a5ed918285 ("Btrfs: implement the free space B-tree")
CC: stable@vger.kernel.org # 4.14+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-19 16:36:22 +02:00
Christoph Hellwig
ad87179a20 btrfs: fix file_offset for REQ_BTRFS_ONE_ORDERED bios that get split
[ Upstream commit c731cd0b6d ]

If a bio gets split, it needs to have a proper file_offset for checksum
validation and repair to work properly.

Based on feedback from Josef, commit 852eee62d3 ("btrfs: allow
btrfs_submit_bio to split bios") skipped this adjustment for ONE_ORDERED
bios.  But if we actually ever need to split a ONE_ORDERED read bio, this
will lead to a wrong file offset in the repair code.  Right now the only
user of the file_offset is logging of an error message so this is mostly
harmless, but the wrong offset might be more problematic for additional
users in the future.

Fixes: 852eee62d3 ("btrfs: allow btrfs_submit_bio to split bios")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-19 16:35:13 +02:00
Christoph Hellwig
82e3a2913b btrfs: don't treat zoned writeback as being from an async helper thread
[ Upstream commit 7027f87108 ]

When extent_write_locked_range was originally added, it was only used
writing back compressed pages from an async helper thread.  But it is
now also used for writing back pages on zoned devices, where it is
called directly from the ->writepage context.  In this case we want to
be able to pass on the writeback_control instead of creating a new one,
and more importantly want to use all the normal cgroup interaction
instead of potentially deferring writeback to another helper.

Fixes: 898793d992 ("btrfs: zoned: write out partially allocated region")
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-19 16:35:13 +02:00
Christoph Hellwig
558c1b78d7 btrfs: only call __extent_writepage_io from extent_write_locked_range
[ Upstream commit eb34dceace ]

__extent_writepage does a lot of things that make no sense for
extent_write_locked_range, given that extent_write_locked_range itself is
called from __extent_writepage either directly or through a workqueue,
and all this work has already been done in the first invocation and the
pages haven't been unlocked since.  Call __extent_writepage_io directly
instead and open code the logic tracked in
btrfs_bio_ctrl::extent_locked.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Stable-dep-of: 7027f87108 ("btrfs: don't treat zoned writeback as being from an async helper thread")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-19 16:35:13 +02:00