Commit Graph

1297 Commits

Author SHA1 Message Date
Dominique Martinet
25090e9bb0 btrfs: add missing mutex_unlock in btrfs_relocate_sys_chunks()
commit 9af503d912 upstream.

The previous patch that replaced BUG_ON by error handling forgot to
unlock the mutex in the error path.

Link: https://lore.kernel.org/all/Zh%2fHpAGFqa7YAFuM@duo.ucw.cz
Reported-by: Pavel Machek <pavel@denx.de>
Fixes: 7411055db5 ("btrfs: handle chunk tree lookup error in btrfs_relocate_sys_chunks()")
CC: stable@vger.kernel.org
Reviewed-by: Pavel Machek <pavel@denx.de>
Signed-off-by: Dominique Martinet <dominique.martinet@atmark-techno.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>
2024-05-17 11:56:19 +02:00
Anand Jain
681fb3c25d btrfs: return accurate error code on open failure in open_fs_devices()
[ Upstream commit 2f1aeab9fc ]

When attempting to exclusive open a device which has no exclusive open
permission, such as a physical device associated with the flakey dm
device, the open operation will fail, resulting in a mount failure.

In this particular scenario, we erroneously return -EINVAL instead of the
correct error code provided by the bdev_open_by_path() function, which is
-EBUSY.

Fix this, by returning error code from the bdev_open_by_path() function.
With this correction, the mount error message will align with that of
ext4 and xfs.

Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-05-17 11:56:04 +02:00
David Sterba
36c2a2863b btrfs: handle chunk tree lookup error in btrfs_relocate_sys_chunks()
[ Upstream commit 7411055db5 ]

The unhandled case in btrfs_relocate_sys_chunks() loop is a corruption,
as it could be caused only by two impossible conditions:

- at first the search key is set up to look for a chunk tree item, with
  offset -1, this is an inexact search and the key->offset will contain
  the correct offset upon a successful search, a valid chunk tree item
  cannot have an offset -1

- after first successful search, the found_key corresponds to a chunk
  item, the offset is decremented by 1 before the next loop, it's
  impossible to find a chunk item there due to alignment and size
  constraints

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-13 13:05:00 +02:00
Filipe Manana
50361c2af7 btrfs: fix off-by-one chunk length calculation at contains_pending_extent()
[ Upstream commit ae6bd7f9b4 ]

At contains_pending_extent() the value of the end offset of a chunk we
found in the device's allocation state io tree is inclusive, so when
we calculate the length we pass to the in_range() macro, we must sum
1 to the expression "physical_end - physical_offset".

In practice the wrong calculation should be harmless as chunks sizes
are never 1 byte and we should never have 1 byte ranges of unallocated
space. Nevertheless fix the wrong calculation.

Reported-by: Alex Lyakas <alex.lyakas@zadara.com>
Link: https://lore.kernel.org/linux-btrfs/CAOcd+r30e-f4R-5x-S7sV22RJPe7+pgwherA6xqN2_qe7o4XTg@mail.gmail.com/
Fixes: 1c11b63eff ("btrfs: replace pending/pinned chunks lists with io tree")
CC: stable@vger.kernel.org # 6.1+
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: Sasha Levin <sashal@kernel.org>
2024-04-03 15:19:31 +02:00
Filipe Manana
32912ee869 btrfs: make error messages more clear when getting a chunk map
commit 7d410d5efe upstream.

When getting a chunk map, at btrfs_get_chunk_map(), we do some sanity
checks to verify we found a chunk map and that map found covers the
logical address the caller passed in. However the messages aren't very
clear in the sense that don't mention the issue is with a chunk map and
one of them prints the 'length' argument as if it were the end offset of
the requested range (while the in the string format we use %llu-%llu
which suggests a range, and the second %llu-%llu is actually a range for
the chunk map). So improve these two details in the error messages.

CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.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>
2023-12-08 08:51:16 +01:00
Filipe Manana
86742a963f btrfs: fix off-by-one when checking chunk map includes logical address
commit 5fba5a5718 upstream.

At btrfs_get_chunk_map() we get the extent map for the chunk that contains
the given logical address stored in the 'logical' argument. Then we do
sanity checks to verify the extent map contains the logical address. One
of these checks verifies if the extent map covers a range with an end
offset behind the target logical address - however this check has an
off-by-one error since it will consider an extent map whose start offset
plus its length matches the target logical address as inclusive, while
the fact is that the last byte it covers is behind the target logical
address (by 1).

So fix this condition by using '<=' rather than '<' when comparing the
extent map's "start + length" against the target logical address.

CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Josef Bacik <josef@toxicpanda.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>
2023-12-08 08:51:16 +01:00
Zygo Blaxell
fb8e1608b0 btrfs: fix stripe length calculation for non-zoned data chunk allocation
commit 8a540e990d upstream.

Commit f6fca3917b "btrfs: store chunk size in space-info struct"
broke data chunk allocations on non-zoned multi-device filesystems when
using default chunk_size.  Commit 5da431b71d "btrfs: fix the max chunk
size and stripe length calculation" partially fixed that, and this patch
completes the fix for that case.

After commit f6fca3917b and 5da431b71d, the sequence of events for
a data chunk allocation on a non-zoned filesystem is:

        1.  btrfs_create_chunk calls init_alloc_chunk_ctl, which copies
        space_info->chunk_size (default 10 GiB) to ctl->max_stripe_len
        unmodified.  Before f6fca3917b, ctl->max_stripe_len value was
        1 GiB for non-zoned data chunks and not configurable.

        2.  btrfs_create_chunk calls gather_device_info which consumes
        and produces more fields of chunk_ctl.

        3.  gather_device_info multiplies ctl->max_stripe_len by
        ctl->dev_stripes (which is 1 in all cases except dup)
        and calls find_free_dev_extent with that number as num_bytes.

        4.  find_free_dev_extent locates the first dev_extent hole on
        a device which is at least as large as num_bytes.  With default
        max_chunk_size from f6fca3917b, it finds the first hole which is
        longer than 10 GiB, or the largest hole if that hole is shorter
        than 10 GiB.  This is different from the pre-f6fca3917b4d
        behavior, where num_bytes is 1 GiB, and find_free_dev_extent
        may choose a different hole.

        5.  gather_device_info repeats step 4 with all devices to find
        the first or largest dev_extent hole that can be allocated on
        each device.

        6.  gather_device_info sorts the device list by the hole size
        on each device, using total unallocated space on each device to
        break ties, then returns to btrfs_create_chunk with the list.

        7.  btrfs_create_chunk calls decide_stripe_size_regular.

        8.  decide_stripe_size_regular finds the largest stripe_len that
        fits across the first nr_devs device dev_extent holes that were
        found by gather_device_info (and satisfies other constraints
        on stripe_len that are not relevant here).

        9.  decide_stripe_size_regular caps the length of the stripe it
        computed at 1 GiB.  This cap appeared in 5da431b71d to correct
        one of the other regressions introduced in f6fca3917b.

        10.  btrfs_create_chunk creates a new chunk with the above
        computed size and number of devices.

At step 4, gather_device_info() has found a location where stripe up to
10 GiB in length could be allocated on several devices, and selected
which devices should have a dev_extent allocated on them, but at step
9, only 1 GiB of the space that was found on each device can be used.
This mismatch causes new suboptimal chunk allocation cases that did not
occur in pre-f6fca3917b4d kernels.

Consider a filesystem using raid1 profile with 3 devices.  After some
balances, device 1 has 10x 1 GiB unallocated space, while devices 2
and 3 have 1x 10 GiB unallocated space, i.e. the same total amount of
space, but distributed across different numbers of dev_extent holes.
For visualization, let's ignore all the chunks that were allocated before
this point, and focus on the remaining holes:

        Device 1:  [_] [_] [_] [_] [_] [_] [_] [_] [_] [_] (10x 1 GiB unallocated)
        Device 2:  [__________] (10 GiB contig unallocated)
        Device 3:  [__________] (10 GiB contig unallocated)

Before f6fca3917b, the allocator would fill these optimally by
allocating chunks with dev_extents on devices 1 and 2 ([12]), 1 and 3
([13]), or 2 and 3 ([23]):

        [after 0 chunk allocations]
        Device 1:  [_] [_] [_] [_] [_] [_] [_] [_] [_] [_] (10 GiB)
        Device 2:  [__________] (10 GiB)
        Device 3:  [__________] (10 GiB)

        [after 1 chunk allocation]
        Device 1:  [12] [_] [_] [_] [_] [_] [_] [_] [_] [_]
        Device 2:  [12] [_________] (9 GiB)
        Device 3:  [__________] (10 GiB)

        [after 2 chunk allocations]
        Device 1:  [12] [13] [_] [_] [_] [_] [_] [_] [_] [_] (8 GiB)
        Device 2:  [12] [_________] (9 GiB)
        Device 3:  [13] [_________] (9 GiB)

        [after 3 chunk allocations]
        Device 1:  [12] [13] [12] [_] [_] [_] [_] [_] [_] [_] (7 GiB)
        Device 2:  [12] [12] [________] (8 GiB)
        Device 3:  [13] [_________] (9 GiB)

        [...]

        [after 12 chunk allocations]
        Device 1:  [12] [13] [12] [13] [12] [13] [12] [13] [_] [_] (2 GiB)
        Device 2:  [12] [12] [23] [23] [12] [12] [23] [23] [__] (2 GiB)
        Device 3:  [13] [13] [23] [23] [13] [23] [13] [23] [__] (2 GiB)

        [after 13 chunk allocations]
        Device 1:  [12] [13] [12] [13] [12] [13] [12] [13] [12] [_] (1 GiB)
        Device 2:  [12] [12] [23] [23] [12] [12] [23] [23] [12] [_] (1 GiB)
        Device 3:  [13] [13] [23] [23] [13] [23] [13] [23] [__] (2 GiB)

        [after 14 chunk allocations]
        Device 1:  [12] [13] [12] [13] [12] [13] [12] [13] [12] [13] (full)
        Device 2:  [12] [12] [23] [23] [12] [12] [23] [23] [12] [_] (1 GiB)
        Device 3:  [13] [13] [23] [23] [13] [23] [13] [23] [13] [_] (1 GiB)

        [after 15 chunk allocations]
        Device 1:  [12] [13] [12] [13] [12] [13] [12] [13] [12] [13] (full)
        Device 2:  [12] [12] [23] [23] [12] [12] [23] [23] [12] [23] (full)
        Device 3:  [13] [13] [23] [23] [13] [23] [13] [23] [13] [23] (full)

This allocates all of the space with no waste.  The sorting function used
by gather_device_info considers free space holes above 1 GiB in length
to be equal to 1 GiB, so once find_free_dev_extent locates a sufficiently
long hole on each device, all the holes appear equal in the sort, and the
comparison falls back to sorting devices by total free space.  This keeps
usable space on each device equal so they can all be filled completely.

After f6fca3917b, the allocator prefers the devices with larger holes
over the devices with more free space, so it makes bad allocation choices:

        [after 1 chunk allocation]
        Device 1:  [_] [_] [_] [_] [_] [_] [_] [_] [_] [_] (10 GiB)
        Device 2:  [23] [_________] (9 GiB)
        Device 3:  [23] [_________] (9 GiB)

        [after 2 chunk allocations]
        Device 1:  [_] [_] [_] [_] [_] [_] [_] [_] [_] [_] (10 GiB)
        Device 2:  [23] [23] [________] (8 GiB)
        Device 3:  [23] [23] [________] (8 GiB)

        [after 3 chunk allocations]
        Device 1:  [_] [_] [_] [_] [_] [_] [_] [_] [_] [_] (10 GiB)
        Device 2:  [23] [23] [23] [_______] (7 GiB)
        Device 3:  [23] [23] [23] [_______] (7 GiB)

        [...]

        [after 9 chunk allocations]
        Device 1:  [_] [_] [_] [_] [_] [_] [_] [_] [_] [_] (10 GiB)
        Device 2:  [23] [23] [23] [23] [23] [23] [23] [23] [23] [_] (1 GiB)
        Device 3:  [23] [23] [23] [23] [23] [23] [23] [23] [23] [_] (1 GiB)

        [after 10 chunk allocations]
        Device 1:  [12] [_] [_] [_] [_] [_] [_] [_] [_] [_] (9 GiB)
        Device 2:  [23] [23] [23] [23] [23] [23] [23] [23] [12] (full)
        Device 3:  [23] [23] [23] [23] [23] [23] [23] [23] [_] (1 GiB)

        [after 11 chunk allocations]
        Device 1:  [12] [13] [_] [_] [_] [_] [_] [_] [_] [_] (8 GiB)
        Device 2:  [23] [23] [23] [23] [23] [23] [23] [23] [12] (full)
        Device 3:  [23] [23] [23] [23] [23] [23] [23] [23] [13] (full)

No further allocations are possible, with 8 GiB wasted (4 GiB of data
space).  The sort in gather_device_info now considers free space in
holes longer than 1 GiB to be distinct, so it will prefer devices 2 and
3 over device 1 until all but 1 GiB is allocated on devices 2 and 3.
At that point, with only 1 GiB unallocated on every device, the largest
hole length on each device is equal at 1 GiB, so the sort finally moves
to ordering the devices with the most free space, but by this time it
is too late to make use of the free space on device 1.

Note that it's possible to contrive a case where the pre-f6fca3917b4d
allocator fails the same way, but these cases generally have extensive
dev_extent fragmentation as a precondition (e.g. many holes of 768M
in length on one device, and few holes 1 GiB in length on the others).
With the regression in f6fca3917b, bad chunk allocation can occur even
under optimal conditions, when all dev_extent holes are exact multiples
of stripe_len in length, as in the example above.

Also note that post-f6fca3917b4d kernels do treat dev_extent holes
larger than 10 GiB as equal, so the bad behavior won't show up on a
freshly formatted filesystem; however, as the filesystem ages and fills
up, and holes ranging from 1 GiB to 10 GiB in size appear, the problem
can show up as a failure to balance after adding or removing devices,
or an unexpected shortfall in available space due to unequal allocation.

To fix the regression and make data chunk allocation work
again, set ctl->max_stripe_len back to the original SZ_1G, or
space_info->chunk_size if that's smaller (the latter can happen if the
user set space_info->chunk_size to less than 1 GiB via sysfs, or it's
a 32 MiB system chunk with a hardcoded chunk_size and stripe_len).

While researching the background of the earlier commits, I found that an
identical fix was already proposed at:

  https://lore.kernel.org/linux-btrfs/de83ac46-a4a3-88d3-85ce-255b7abc5249@gmx.com/

The previous review missed one detail:  ctl->max_stripe_len is used
before decide_stripe_size_regular() is called, when it is too late for
the changes in that function to have any effect.  ctl->max_stripe_len is
not used directly by decide_stripe_size_regular(), but the parameter
does heavily influence the per-device free space data presented to
the function.

Fixes: f6fca3917b ("btrfs: store chunk size in space-info struct")
CC: stable@vger.kernel.org # 6.1+
Link: https://lore.kernel.org/linux-btrfs/20231007051421.19657-1-ce3g8jdj@umail.furryterror.org/
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-25 12:03:04 +02:00
Anand Jain
31242daa10 btrfs: add a helper to read the superblock metadata_uuid
[ Upstream commit 4844c3664a ]

In some cases, we need to read the FSID from the superblock when the
metadata_uuid is not set, and otherwise, read the metadata_uuid. So,
add a helper.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Stable-dep-of: 6bfe3959b0 ("btrfs: compare the correct fsid/metadata_uuid in btrfs_validate_super")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-23 11:11:08 +02:00
xiaoshoukui
ceb9ba8e30 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 17:52:31 +02:00
Christoph Hellwig
9c85f71d3f 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 08:50:39 +02:00
Josef Bacik
ddf7e8984c 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 08:50:26 +02:00
Genjian Zhang
17e5ce4d89 btrfs: fix uninitialized variable warnings
commit 8ba7d5f5ba upstream.

There are some warnings on older compilers (gcc 10, 7) or non-x86_64
architectures (aarch64).  As btrfs wants to enable -Wmaybe-uninitialized
by default, fix the warnings even though it's not necessary on recent
compilers (gcc 12+).

../fs/btrfs/volumes.c: In function ‘btrfs_init_new_device’:
../fs/btrfs/volumes.c:2703:3: error: ‘seed_devices’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
 2703 |   btrfs_setup_sprout(fs_info, seed_devices);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

../fs/btrfs/send.c: In function ‘get_cur_inode_state’:
../include/linux/compiler.h:70:32: error: ‘right_gen’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
   70 |   (__if_trace.miss_hit[1]++,1) :  \
      |                                ^
../fs/btrfs/send.c:1878:6: note: ‘right_gen’ was declared here
 1878 |  u64 right_gen;
      |      ^~~~~~~~~

Reported-by: k2ci <kernel-bot@kylinos.cn>
Signed-off-by: Genjian Zhang <zhanggenjian@kylinos.cn>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
Cc: Ammar Faizi <ammarfaizi2@gnuweeb.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-01 08:26:27 +09:00
Anand Jain
8a6539ea36 btrfs: scan device in non-exclusive mode
commit 50d281fc43 upstream.

This fixes mkfs/mount/check failures due to race with systemd-udevd
scan.

During the device scan initiated by systemd-udevd, other user space
EXCL operations such as mkfs, mount, or check may get blocked and result
in a "Device or resource busy" error. This is because the device
scan process opens the device with the EXCL flag in the kernel.

Two reports were received:

 - btrfs/179 test case, where the fsck command failed with the -EBUSY
   error

 - LTP pwritev03 test case, where mkfs.vfs failed with
   the -EBUSY error, when mkfs.vfs tried to overwrite old btrfs filesystem
   on the device.

In both cases, fsck and mkfs (respectively) were racing with a
systemd-udevd device scan, and systemd-udevd won, resulting in the
-EBUSY error for fsck and mkfs.

Reproducing the problem has been difficult because there is a very
small window during which these userspace threads can race to
acquire the exclusive device open. Even on the system where the problem
was observed, the problem occurrences were anywhere between 10 to 400
iterations and chances of reproducing decreases with debug printk()s.

However, an exclusive device open is unnecessary for the scan process,
as there are no write operations on the device during scan. Furthermore,
during the mount process, the superblock is re-read in the below
function call chain:

  btrfs_mount_root
   btrfs_open_devices
    open_fs_devices
     btrfs_open_one_device
       btrfs_get_bdev_and_sb

So, to fix this issue, removes the FMODE_EXCL flag from the scan
operation, and add a comment.

The case where mkfs may still write to the device and a scan is running,
the btrfs signature is not written at that time so scan will not
recognize such device.

Reported-by: Sherry Yang <sherry.yang@oracle.com>
Reported-by: kernel test robot <oliver.sang@intel.com>
Link: https://lore.kernel.org/oe-lkp/202303170839.fdf23068-oliver.sang@intel.com
CC: stable@vger.kernel.org # 5.4+
Signed-off-by: Anand Jain <anand.jain@oracle.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>
2023-04-06 12:10:51 +02:00
Filipe Manana
6134a4bb6b btrfs: fix deadlock when aborting transaction during relocation with scrub
commit 2d82a40aa7 upstream.

Before relocating a block group we pause scrub, then do the relocation and
then unpause scrub. The relocation process requires starting and committing
a transaction, and if we have a failure in the critical section of the
transaction commit path (transaction state >= TRANS_STATE_COMMIT_START),
we will deadlock if there is a paused scrub.

That results in stack traces like the following:

  [42.479] BTRFS info (device sdc): relocating block group 53876686848 flags metadata|raid6
  [42.936] BTRFS warning (device sdc): Skipping commit of aborted transaction.
  [42.936] ------------[ cut here ]------------
  [42.936] BTRFS: Transaction aborted (error -28)
  [42.936] WARNING: CPU: 11 PID: 346822 at fs/btrfs/transaction.c:1977 btrfs_commit_transaction+0xcc8/0xeb0 [btrfs]
  [42.936] Modules linked in: dm_flakey dm_mod loop btrfs (...)
  [42.936] CPU: 11 PID: 346822 Comm: btrfs Tainted: G        W          6.3.0-rc2-btrfs-next-127+ #1
  [42.936] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
  [42.936] RIP: 0010:btrfs_commit_transaction+0xcc8/0xeb0 [btrfs]
  [42.936] Code: ff ff 45 8b (...)
  [42.936] RSP: 0018:ffffb58649633b48 EFLAGS: 00010282
  [42.936] RAX: 0000000000000000 RBX: ffff8be6ef4d5bd8 RCX: 0000000000000000
  [42.936] RDX: 0000000000000002 RSI: ffffffffb35e7782 RDI: 00000000ffffffff
  [42.936] RBP: ffff8be6ef4d5c98 R08: 0000000000000000 R09: ffffb586496339e8
  [42.936] R10: 0000000000000001 R11: 0000000000000001 R12: ffff8be6d38c7c00
  [42.936] R13: 00000000ffffffe4 R14: ffff8be6c268c000 R15: ffff8be6ef4d5cf0
  [42.936] FS:  00007f381a82b340(0000) GS:ffff8beddfcc0000(0000) knlGS:0000000000000000
  [42.936] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [42.936] CR2: 00007f1e35fb7638 CR3: 0000000117680006 CR4: 0000000000370ee0
  [42.936] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [42.936] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [42.936] Call Trace:
  [42.936]  <TASK>
  [42.936]  ? start_transaction+0xcb/0x610 [btrfs]
  [42.936]  prepare_to_relocate+0x111/0x1a0 [btrfs]
  [42.936]  relocate_block_group+0x57/0x5d0 [btrfs]
  [42.936]  ? btrfs_wait_nocow_writers+0x25/0xb0 [btrfs]
  [42.936]  btrfs_relocate_block_group+0x248/0x3c0 [btrfs]
  [42.936]  ? __pfx_autoremove_wake_function+0x10/0x10
  [42.936]  btrfs_relocate_chunk+0x3b/0x150 [btrfs]
  [42.936]  btrfs_balance+0x8ff/0x11d0 [btrfs]
  [42.936]  ? __kmem_cache_alloc_node+0x14a/0x410
  [42.936]  btrfs_ioctl+0x2334/0x32c0 [btrfs]
  [42.937]  ? mod_objcg_state+0xd2/0x360
  [42.937]  ? refill_obj_stock+0xb0/0x160
  [42.937]  ? seq_release+0x25/0x30
  [42.937]  ? __rseq_handle_notify_resume+0x3b5/0x4b0
  [42.937]  ? percpu_counter_add_batch+0x2e/0xa0
  [42.937]  ? __x64_sys_ioctl+0x88/0xc0
  [42.937]  __x64_sys_ioctl+0x88/0xc0
  [42.937]  do_syscall_64+0x38/0x90
  [42.937]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
  [42.937] RIP: 0033:0x7f381a6ffe9b
  [42.937] Code: 00 48 89 44 24 (...)
  [42.937] RSP: 002b:00007ffd45ecf060 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  [42.937] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f381a6ffe9b
  [42.937] RDX: 00007ffd45ecf150 RSI: 00000000c4009420 RDI: 0000000000000003
  [42.937] RBP: 0000000000000003 R08: 0000000000000013 R09: 0000000000000000
  [42.937] R10: 00007f381a60c878 R11: 0000000000000246 R12: 00007ffd45ed0423
  [42.937] R13: 00007ffd45ecf150 R14: 0000000000000000 R15: 00007ffd45ecf148
  [42.937]  </TASK>
  [42.937] ---[ end trace 0000000000000000 ]---
  [42.937] BTRFS: error (device sdc: state A) in cleanup_transaction:1977: errno=-28 No space left
  [59.196] INFO: task btrfs:346772 blocked for more than 120 seconds.
  [59.196]       Tainted: G        W          6.3.0-rc2-btrfs-next-127+ #1
  [59.196] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [59.196] task:btrfs           state:D stack:0     pid:346772 ppid:1      flags:0x00004002
  [59.196] Call Trace:
  [59.196]  <TASK>
  [59.196]  __schedule+0x392/0xa70
  [59.196]  ? __pv_queued_spin_lock_slowpath+0x165/0x370
  [59.196]  schedule+0x5d/0xd0
  [59.196]  __scrub_blocked_if_needed+0x74/0xc0 [btrfs]
  [59.197]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.197]  scrub_pause_off+0x21/0x50 [btrfs]
  [59.197]  scrub_simple_mirror+0x1c7/0x950 [btrfs]
  [59.197]  ? scrub_parity_put+0x1a5/0x1d0 [btrfs]
  [59.198]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.198]  scrub_stripe+0x20d/0x740 [btrfs]
  [59.198]  scrub_chunk+0xc4/0x130 [btrfs]
  [59.198]  scrub_enumerate_chunks+0x3e4/0x7a0 [btrfs]
  [59.198]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.198]  btrfs_scrub_dev+0x236/0x6a0 [btrfs]
  [59.199]  ? btrfs_ioctl+0xd97/0x32c0 [btrfs]
  [59.199]  ? _copy_from_user+0x7b/0x80
  [59.199]  btrfs_ioctl+0xde1/0x32c0 [btrfs]
  [59.199]  ? refill_stock+0x33/0x50
  [59.199]  ? should_failslab+0xa/0x20
  [59.199]  ? kmem_cache_alloc_node+0x151/0x460
  [59.199]  ? alloc_io_context+0x1b/0x80
  [59.199]  ? preempt_count_add+0x70/0xa0
  [59.199]  ? __x64_sys_ioctl+0x88/0xc0
  [59.199]  __x64_sys_ioctl+0x88/0xc0
  [59.199]  do_syscall_64+0x38/0x90
  [59.199]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
  [59.199] RIP: 0033:0x7f82ffaffe9b
  [59.199] RSP: 002b:00007f82ff9fcc50 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  [59.199] RAX: ffffffffffffffda RBX: 000055b191e36310 RCX: 00007f82ffaffe9b
  [59.199] RDX: 000055b191e36310 RSI: 00000000c400941b RDI: 0000000000000003
  [59.199] RBP: 0000000000000000 R08: 00007fff1575016f R09: 0000000000000000
  [59.199] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f82ff9fd640
  [59.199] R13: 000000000000006b R14: 00007f82ffa87580 R15: 0000000000000000
  [59.199]  </TASK>
  [59.199] INFO: task btrfs:346773 blocked for more than 120 seconds.
  [59.200]       Tainted: G        W          6.3.0-rc2-btrfs-next-127+ #1
  [59.200] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [59.201] task:btrfs           state:D stack:0     pid:346773 ppid:1      flags:0x00004002
  [59.201] Call Trace:
  [59.201]  <TASK>
  [59.201]  __schedule+0x392/0xa70
  [59.201]  ? __pv_queued_spin_lock_slowpath+0x165/0x370
  [59.201]  schedule+0x5d/0xd0
  [59.201]  __scrub_blocked_if_needed+0x74/0xc0 [btrfs]
  [59.201]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.201]  scrub_pause_off+0x21/0x50 [btrfs]
  [59.202]  scrub_simple_mirror+0x1c7/0x950 [btrfs]
  [59.202]  ? scrub_parity_put+0x1a5/0x1d0 [btrfs]
  [59.202]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.202]  scrub_stripe+0x20d/0x740 [btrfs]
  [59.202]  scrub_chunk+0xc4/0x130 [btrfs]
  [59.203]  scrub_enumerate_chunks+0x3e4/0x7a0 [btrfs]
  [59.203]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.203]  btrfs_scrub_dev+0x236/0x6a0 [btrfs]
  [59.203]  ? btrfs_ioctl+0xd97/0x32c0 [btrfs]
  [59.203]  ? _copy_from_user+0x7b/0x80
  [59.203]  btrfs_ioctl+0xde1/0x32c0 [btrfs]
  [59.204]  ? should_failslab+0xa/0x20
  [59.204]  ? kmem_cache_alloc_node+0x151/0x460
  [59.204]  ? alloc_io_context+0x1b/0x80
  [59.204]  ? preempt_count_add+0x70/0xa0
  [59.204]  ? __x64_sys_ioctl+0x88/0xc0
  [59.204]  __x64_sys_ioctl+0x88/0xc0
  [59.204]  do_syscall_64+0x38/0x90
  [59.204]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
  [59.204] RIP: 0033:0x7f82ffaffe9b
  [59.204] RSP: 002b:00007f82ff1fbc50 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  [59.204] RAX: ffffffffffffffda RBX: 000055b191e36790 RCX: 00007f82ffaffe9b
  [59.204] RDX: 000055b191e36790 RSI: 00000000c400941b RDI: 0000000000000003
  [59.204] RBP: 0000000000000000 R08: 00007fff1575016f R09: 0000000000000000
  [59.204] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f82ff1fc640
  [59.204] R13: 000000000000006b R14: 00007f82ffa87580 R15: 0000000000000000
  [59.204]  </TASK>
  [59.204] INFO: task btrfs:346774 blocked for more than 120 seconds.
  [59.205]       Tainted: G        W          6.3.0-rc2-btrfs-next-127+ #1
  [59.205] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [59.206] task:btrfs           state:D stack:0     pid:346774 ppid:1      flags:0x00004002
  [59.206] Call Trace:
  [59.206]  <TASK>
  [59.206]  __schedule+0x392/0xa70
  [59.206]  schedule+0x5d/0xd0
  [59.206]  __scrub_blocked_if_needed+0x74/0xc0 [btrfs]
  [59.206]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.206]  scrub_pause_off+0x21/0x50 [btrfs]
  [59.207]  scrub_simple_mirror+0x1c7/0x950 [btrfs]
  [59.207]  ? scrub_parity_put+0x1a5/0x1d0 [btrfs]
  [59.207]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.207]  scrub_stripe+0x20d/0x740 [btrfs]
  [59.208]  scrub_chunk+0xc4/0x130 [btrfs]
  [59.208]  scrub_enumerate_chunks+0x3e4/0x7a0 [btrfs]
  [59.208]  ? __mutex_unlock_slowpath.isra.0+0x9a/0x120
  [59.208]  btrfs_scrub_dev+0x236/0x6a0 [btrfs]
  [59.208]  ? btrfs_ioctl+0xd97/0x32c0 [btrfs]
  [59.209]  ? _copy_from_user+0x7b/0x80
  [59.209]  btrfs_ioctl+0xde1/0x32c0 [btrfs]
  [59.209]  ? should_failslab+0xa/0x20
  [59.209]  ? kmem_cache_alloc_node+0x151/0x460
  [59.209]  ? alloc_io_context+0x1b/0x80
  [59.209]  ? preempt_count_add+0x70/0xa0
  [59.209]  ? __x64_sys_ioctl+0x88/0xc0
  [59.209]  __x64_sys_ioctl+0x88/0xc0
  [59.209]  do_syscall_64+0x38/0x90
  [59.209]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
  [59.209] RIP: 0033:0x7f82ffaffe9b
  [59.209] RSP: 002b:00007f82fe9fac50 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  [59.209] RAX: ffffffffffffffda RBX: 000055b191e36c10 RCX: 00007f82ffaffe9b
  [59.209] RDX: 000055b191e36c10 RSI: 00000000c400941b RDI: 0000000000000003
  [59.209] RBP: 0000000000000000 R08: 00007fff1575016f R09: 0000000000000000
  [59.209] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f82fe9fb640
  [59.209] R13: 000000000000006b R14: 00007f82ffa87580 R15: 0000000000000000
  [59.209]  </TASK>
  [59.209] INFO: task btrfs:346775 blocked for more than 120 seconds.
  [59.210]       Tainted: G        W          6.3.0-rc2-btrfs-next-127+ #1
  [59.210] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [59.211] task:btrfs           state:D stack:0     pid:346775 ppid:1      flags:0x00004002
  [59.211] Call Trace:
  [59.211]  <TASK>
  [59.211]  __schedule+0x392/0xa70
  [59.211]  schedule+0x5d/0xd0
  [59.211]  __scrub_blocked_if_needed+0x74/0xc0 [btrfs]
  [59.211]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.211]  scrub_pause_off+0x21/0x50 [btrfs]
  [59.212]  scrub_simple_mirror+0x1c7/0x950 [btrfs]
  [59.212]  ? scrub_parity_put+0x1a5/0x1d0 [btrfs]
  [59.212]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.212]  scrub_stripe+0x20d/0x740 [btrfs]
  [59.213]  scrub_chunk+0xc4/0x130 [btrfs]
  [59.213]  scrub_enumerate_chunks+0x3e4/0x7a0 [btrfs]
  [59.213]  ? __mutex_unlock_slowpath.isra.0+0x9a/0x120
  [59.213]  btrfs_scrub_dev+0x236/0x6a0 [btrfs]
  [59.213]  ? btrfs_ioctl+0xd97/0x32c0 [btrfs]
  [59.214]  ? _copy_from_user+0x7b/0x80
  [59.214]  btrfs_ioctl+0xde1/0x32c0 [btrfs]
  [59.214]  ? should_failslab+0xa/0x20
  [59.214]  ? kmem_cache_alloc_node+0x151/0x460
  [59.214]  ? alloc_io_context+0x1b/0x80
  [59.214]  ? preempt_count_add+0x70/0xa0
  [59.214]  ? __x64_sys_ioctl+0x88/0xc0
  [59.214]  __x64_sys_ioctl+0x88/0xc0
  [59.214]  do_syscall_64+0x38/0x90
  [59.214]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
  [59.214] RIP: 0033:0x7f82ffaffe9b
  [59.214] RSP: 002b:00007f82fe1f9c50 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  [59.214] RAX: ffffffffffffffda RBX: 000055b191e37090 RCX: 00007f82ffaffe9b
  [59.214] RDX: 000055b191e37090 RSI: 00000000c400941b RDI: 0000000000000003
  [59.214] RBP: 0000000000000000 R08: 00007fff1575016f R09: 0000000000000000
  [59.214] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f82fe1fa640
  [59.214] R13: 000000000000006b R14: 00007f82ffa87580 R15: 0000000000000000
  [59.214]  </TASK>
  [59.214] INFO: task btrfs:346776 blocked for more than 120 seconds.
  [59.215]       Tainted: G        W          6.3.0-rc2-btrfs-next-127+ #1
  [59.216] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [59.217] task:btrfs           state:D stack:0     pid:346776 ppid:1      flags:0x00004002
  [59.217] Call Trace:
  [59.217]  <TASK>
  [59.217]  __schedule+0x392/0xa70
  [59.217]  ? __pv_queued_spin_lock_slowpath+0x165/0x370
  [59.217]  schedule+0x5d/0xd0
  [59.217]  __scrub_blocked_if_needed+0x74/0xc0 [btrfs]
  [59.217]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.217]  scrub_pause_off+0x21/0x50 [btrfs]
  [59.217]  scrub_simple_mirror+0x1c7/0x950 [btrfs]
  [59.217]  ? scrub_parity_put+0x1a5/0x1d0 [btrfs]
  [59.218]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.218]  scrub_stripe+0x20d/0x740 [btrfs]
  [59.218]  scrub_chunk+0xc4/0x130 [btrfs]
  [59.218]  scrub_enumerate_chunks+0x3e4/0x7a0 [btrfs]
  [59.219]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.219]  btrfs_scrub_dev+0x236/0x6a0 [btrfs]
  [59.219]  ? btrfs_ioctl+0xd97/0x32c0 [btrfs]
  [59.219]  ? _copy_from_user+0x7b/0x80
  [59.219]  btrfs_ioctl+0xde1/0x32c0 [btrfs]
  [59.219]  ? should_failslab+0xa/0x20
  [59.219]  ? kmem_cache_alloc_node+0x151/0x460
  [59.219]  ? alloc_io_context+0x1b/0x80
  [59.219]  ? preempt_count_add+0x70/0xa0
  [59.219]  ? __x64_sys_ioctl+0x88/0xc0
  [59.219]  __x64_sys_ioctl+0x88/0xc0
  [59.219]  do_syscall_64+0x38/0x90
  [59.219]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
  [59.219] RIP: 0033:0x7f82ffaffe9b
  [59.219] RSP: 002b:00007f82fd9f8c50 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  [59.219] RAX: ffffffffffffffda RBX: 000055b191e37510 RCX: 00007f82ffaffe9b
  [59.219] RDX: 000055b191e37510 RSI: 00000000c400941b RDI: 0000000000000003
  [59.219] RBP: 0000000000000000 R08: 00007fff1575016f R09: 0000000000000000
  [59.219] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f82fd9f9640
  [59.219] R13: 000000000000006b R14: 00007f82ffa87580 R15: 0000000000000000
  [59.219]  </TASK>
  [59.219] INFO: task btrfs:346822 blocked for more than 120 seconds.
  [59.220]       Tainted: G        W          6.3.0-rc2-btrfs-next-127+ #1
  [59.221] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [59.222] task:btrfs           state:D stack:0     pid:346822 ppid:1      flags:0x00004002
  [59.222] Call Trace:
  [59.222]  <TASK>
  [59.222]  __schedule+0x392/0xa70
  [59.222]  schedule+0x5d/0xd0
  [59.222]  btrfs_scrub_cancel+0x91/0x100 [btrfs]
  [59.222]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.222]  btrfs_commit_transaction+0x572/0xeb0 [btrfs]
  [59.223]  ? start_transaction+0xcb/0x610 [btrfs]
  [59.223]  prepare_to_relocate+0x111/0x1a0 [btrfs]
  [59.223]  relocate_block_group+0x57/0x5d0 [btrfs]
  [59.223]  ? btrfs_wait_nocow_writers+0x25/0xb0 [btrfs]
  [59.223]  btrfs_relocate_block_group+0x248/0x3c0 [btrfs]
  [59.224]  ? __pfx_autoremove_wake_function+0x10/0x10
  [59.224]  btrfs_relocate_chunk+0x3b/0x150 [btrfs]
  [59.224]  btrfs_balance+0x8ff/0x11d0 [btrfs]
  [59.224]  ? __kmem_cache_alloc_node+0x14a/0x410
  [59.224]  btrfs_ioctl+0x2334/0x32c0 [btrfs]
  [59.225]  ? mod_objcg_state+0xd2/0x360
  [59.225]  ? refill_obj_stock+0xb0/0x160
  [59.225]  ? seq_release+0x25/0x30
  [59.225]  ? __rseq_handle_notify_resume+0x3b5/0x4b0
  [59.225]  ? percpu_counter_add_batch+0x2e/0xa0
  [59.225]  ? __x64_sys_ioctl+0x88/0xc0
  [59.225]  __x64_sys_ioctl+0x88/0xc0
  [59.225]  do_syscall_64+0x38/0x90
  [59.225]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
  [59.225] RIP: 0033:0x7f381a6ffe9b
  [59.225] RSP: 002b:00007ffd45ecf060 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  [59.225] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f381a6ffe9b
  [59.225] RDX: 00007ffd45ecf150 RSI: 00000000c4009420 RDI: 0000000000000003
  [59.225] RBP: 0000000000000003 R08: 0000000000000013 R09: 0000000000000000
  [59.225] R10: 00007f381a60c878 R11: 0000000000000246 R12: 00007ffd45ed0423
  [59.225] R13: 00007ffd45ecf150 R14: 0000000000000000 R15: 00007ffd45ecf148
  [59.225]  </TASK>

What happens is the following:

1) A scrub is running, so fs_info->scrubs_running is 1;

2) Task A starts block group relocation, and at btrfs_relocate_chunk() it
   pauses scrub by calling btrfs_scrub_pause(). That increments
   fs_info->scrub_pause_req from 0 to 1 and waits for the scrub task to
   pause (for fs_info->scrubs_paused to be == to fs_info->scrubs_running);

3) The scrub task pauses at scrub_pause_off(), waiting for
   fs_info->scrub_pause_req to decrease to 0;

4) Task A then enters btrfs_relocate_block_group(), and down that call
   chain we start a transaction and then attempt to commit it;

5) When task A calls btrfs_commit_transaction(), it either will do the
   commit itself or wait for some other task that already started the
   commit of the transaction - it doesn't matter which case;

6) The transaction commit enters state TRANS_STATE_COMMIT_START;

7) An error happens during the transaction commit, like -ENOSPC when
   running delayed refs or delayed items for example;

8) This results in calling transaction.c:cleanup_transaction(), where
   we call btrfs_scrub_cancel(), incrementing fs_info->scrub_cancel_req
   from 0 to 1, and blocking this task waiting for fs_info->scrubs_running
   to decrease to 0;

9) From this point on, both the transaction commit and the scrub task
   hang forever:

   1) The transaction commit is waiting for fs_info->scrubs_running to
      be decreased to 0;

   2) The scrub task is at scrub_pause_off() waiting for
      fs_info->scrub_pause_req to decrease to 0 - so it can not proceed
      to stop the scrub and decrement fs_info->scrubs_running from 0 to 1.

   Therefore resulting in a deadlock.

Fix this by having cleanup_transaction(), called if a transaction commit
fails, not call btrfs_scrub_cancel() if relocation is in progress, and
having btrfs_relocate_block_group() call btrfs_scrub_cancel() instead if
the relocation failed and a transaction abort happened.

This was triggered with btrfs/061 from fstests.

Fixes: 55e3a601c8 ("btrfs: Fix data checksum error cause by replace with io-load.")
CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Josef Bacik <josef@toxicpanda.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>
2023-04-06 12:10:51 +02:00
Naohiro Aota
99d232798c btrfs: fix unnecessary increment of read error stat on write error
commit 98e8d36a26 upstream.

Current btrfs_log_dev_io_error() increases the read error count even if the
erroneous IO is a WRITE request. This is because it forget to use "else
if", and all the error WRITE requests counts as READ error as there is (of
course) no REQ_RAHEAD bit set.

Fixes: c3a62baf21 ("btrfs: use chained bios when cloning")
CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-17 08:50:14 +01:00
Anand Jain
51aa10112b btrfs: free device in btrfs_close_devices for a single device filesystem
commit 5f58d783fd upstream.

We have this check to make sure we don't accidentally add older devices
that may have disappeared and re-appeared with an older generation from
being added to an fs_devices (such as a replace source device). This
makes sense, we don't want stale disks in our file system. However for
single disks this doesn't really make sense.

I've seen this in testing, but I was provided a reproducer from a
project that builds btrfs images on loopback devices. The loopback
device gets cached with the new generation, and then if it is re-used to
generate a new file system we'll fail to mount it because the new fs is
"older" than what we have in cache.

Fix this by freeing the cache when closing the device for a single device
filesystem. This will ensure that the mount command passed device path is
scanned successfully during the next mount.

CC: stable@vger.kernel.org # 5.10+
Reported-by: Daan De Meyer <daandemeyer@fb.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Anand Jain <anand.jain@oracle.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>
2023-02-14 19:11:52 +01:00
Josef Bacik
66cf3a8273 btrfs: limit device extents to the device size
commit 3c538de0f2 upstream.

There was a recent regression in btrfs/177 that started happening with
the size class patches ("btrfs: introduce size class to block group
allocator").  This however isn't a regression introduced by those
patches, but rather the bug was uncovered by a change in behavior in
these patches.  The patches triggered more chunk allocations in the
^free-space-tree case, which uncovered a race with device shrink.

The problem is we will set the device total size to the new size, and
use this to find a hole for a device extent.  However during shrink we
may have device extents allocated past this range, so we could
potentially find a hole in a range past our new shrink size.  We don't
actually limit our found extent to the device size anywhere, we assume
that we will not find a hole past our device size.  This isn't true with
shrink as we're relocating block groups and thus creating holes past the
device size.

Fix this by making sure we do not search past the new device size, and
if we wander into any device extents that start after our device size
simply break from the loop and use whatever hole we've already found.

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>
2023-02-14 19:11:40 +01:00
Qu Wenruo
6ec8411329 btrfs: add extra error messages to cover non-ENOMEM errors from device_add_list()
commit ed02363fbb upstream.

[BUG]
When test case btrfs/219 (aka, mount a registered device but with a lower
generation) failed, there is not any useful information for the end user
to find out what's going wrong.

The mount failure just looks like this:

  #  mount -o loop /tmp/219.img2 /mnt/btrfs/
  mount: /mnt/btrfs: mount(2) system call failed: File exists.
         dmesg(1) may have more information after failed mount system call.

While the dmesg contains nothing but the loop device change:

  loop1: detected capacity change from 0 to 524288

[CAUSE]
In device_list_add() we have a lot of extra checks to reject invalid
cases.

That function also contains the regular device scan result like the
following prompt:

  BTRFS: device fsid 6222333e-f9f1-47e6-b306-55ddd4dcaef4 devid 1 transid 8 /dev/loop0 scanned by systemd-udevd (3027)

But unfortunately not all errors have their own error messages, thus if
we hit something wrong in device_add_list(), there may be no error
messages at all.

[FIX]
Add errors message for all non-ENOMEM errors.

For ENOMEM, I'd say we're in a much worse situation, and there should be
some OOM messages way before our call sites.

CC: stable@vger.kernel.org # 6.0+
Signed-off-by: Qu Wenruo <wqu@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>
2023-01-24 07:24:36 +01:00
void0red
169a4cf468 btrfs: fix extent map use-after-free when handling missing device in read_one_chunk
commit 1742e1c90c upstream.

Store the error code before freeing the extent_map. Though it's
reference counted structure, in that function it's the first and last
allocation so this would lead to a potential use-after-free.

The error can happen eg. when chunk is stored on a missing device and
the degraded mount option is missing.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=216721
Reported-by: eriri <1527030098@qq.com>
Fixes: adfb69af7d ("btrfs: add_missing_dev() should return the actual error")
CC: stable@vger.kernel.org # 4.9+
Signed-off-by: void0red <void0red@gmail.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>
2023-01-07 11:11:38 +01:00
Johannes Thumshirn
a8d1b1647b btrfs: zoned: initialize device's zone info for seeding
When performing seeding on a zoned filesystem it is necessary to
initialize each zoned device's btrfs_zoned_device_info structure,
otherwise mounting the filesystem will cause a NULL pointer dereference.

This was uncovered by fstests' testcase btrfs/163.

CC: stable@vger.kernel.org # 5.15+
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-11-07 14:35:24 +01:00
Johannes Thumshirn
21e61ec6d0 btrfs: zoned: clone zoned device info when cloning a device
When cloning a btrfs_device, we're not cloning the associated
btrfs_zoned_device_info structure of the device in case of a zoned
filesystem.

Later on this leads to a NULL pointer dereference when accessing the
device's zone_info for instance when setting a zone as active.

This was uncovered by fstests' testcase btrfs/161.

CC: stable@vger.kernel.org # 5.15+
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-11-07 14:35:21 +01:00
Liu Shixin
0fca385d6e btrfs: fix match incorrectly in dev_args_match_device
syzkaller found a failed assertion:

  assertion failed: (args->devid != (u64)-1) || args->missing, in fs/btrfs/volumes.c:6921

This can be triggered when we set devid to (u64)-1 by ioctl. In this
case, the match of devid will be skipped and the match of device may
succeed incorrectly.

Patch 562d7b1512 introduced this function which is used to match device.
This function contains two matching scenarios, we can distinguish them by
checking the value of args->missing rather than check whether args->devid
and args->uuid is default value.

Reported-by: syzbot+031687116258450f9853@syzkaller.appspotmail.com
Fixes: 562d7b1512 ("btrfs: handle device lookup with btrfs_dev_lookup_args")
CC: stable@vger.kernel.org # 5.16+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-11-07 14:30:45 +01:00
Qu Wenruo
76a66ba101 btrfs: don't use btrfs_chunk::sub_stripes from disk
[BUG]
There are two reports (the earliest one from LKP, a more recent one from
kernel bugzilla) that we can have some chunks with 0 as sub_stripes.

This will cause divide-by-zero errors at btrfs_rmap_block, which is
introduced by a recent kernel patch ac0677348f ("btrfs: merge
calculations for simple striped profiles in btrfs_rmap_block"):

		if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
				 BTRFS_BLOCK_GROUP_RAID10)) {
			stripe_nr = stripe_nr * map->num_stripes + i;
			stripe_nr = div_u64(stripe_nr, map->sub_stripes); <<<
		}

[CAUSE]
From the more recent report, it has been proven that we have some chunks
with 0 as sub_stripes, mostly caused by older mkfs.

It turns out that the mkfs.btrfs fix is only introduced in 6718ab4d33aa
("btrfs-progs: Initialize sub_stripes to 1 in btrfs_alloc_data_chunk")
which is included in v5.4 btrfs-progs release.

So there would be quite some old filesystems with such 0 sub_stripes.

[FIX]
Just don't trust the sub_stripes values from disk.

We have a trusted btrfs_raid_array[] to fetch the correct sub_stripes
numbers for each profile and that are fixed.

By this, we can keep the compatibility with older filesystems while
still avoid divide-by-zero bugs.

Reported-by: kernel test robot <oliver.sang@intel.com>
Reported-by: Viktor Kuzmin <kvaster@gmail.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=216559
Fixes: ac0677348f ("btrfs: merge calculations for simple striped profiles in btrfs_rmap_block")
CC: stable@vger.kernel.org # 6.0
Reviewed-by: Su Yue <glass@fydeos.io>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-10-25 10:17:33 +02:00
Qu Wenruo
a05d3c9153 btrfs: check superblock to ensure the fs was not modified at thaw time
[BACKGROUND]
There is an incident report that, one user hibernated the system, with
one btrfs on removable device still mounted.

Then by some incident, the btrfs got mounted and modified by another
system/OS, then back to the hibernated system.

After resuming from the hibernation, new write happened into the victim btrfs.

Now the fs is completely broken, since the underlying btrfs is no longer
the same one before the hibernation, and the user lost their data due to
various transid mismatch.

[REPRODUCER]
We can emulate the situation using the following small script:

  truncate -s 1G $dev
  mkfs.btrfs -f $dev
  mount $dev $mnt
  fsstress -w -d $mnt -n 500
  sync
  xfs_freeze -f $mnt
  cp $dev $dev.backup

  # There is no way to mount the same cloned fs on the same system,
  # as the conflicting fsid will be rejected by btrfs.
  # Thus here we have to wipe the fs using a different btrfs.
  mkfs.btrfs -f $dev.backup

  dd if=$dev.backup of=$dev bs=1M
  xfs_freeze -u $mnt
  fsstress -w -d $mnt -n 20
  umount $mnt
  btrfs check $dev

The final fsck will fail due to some tree blocks has incorrect fsid.

This is enough to emulate the problem hit by the unfortunate user.

[ENHANCEMENT]
Although such case should not be that common, it can still happen from
time to time.

From the view of btrfs, we can detect any unexpected super block change,
and if there is any unexpected change, we just mark the fs read-only,
and thaw the fs.

By this we can limit the damage to minimal, and I hope no one would lose
their data by this anymore.

Suggested-by: Goffredo Baroncelli <kreijack@libero.it>
Link: https://lore.kernel.org/linux-btrfs/83bf3b4b-7f4c-387a-b286-9251e3991e34@bluemole.com/
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:27:59 +02:00
Christoph Hellwig
928ff3beb8 btrfs: stop allocation a btrfs_io_context for simple I/O
The I/O context structure is only used to pass the btrfs_device to
the end I/O handler for I/Os that go to a single device.

Stop allocating the I/O context for these cases by passing the optional
btrfs_io_stripe argument to __btrfs_map_block to query the mapping
information and then using a fast path submission and I/O completion
handler.  As the old btrfs_io_context based I/O submission path is
only used for mirrored writes, rename the functions to make that
clear and stop setting the btrfs_bio device and mirror_num field
that is only used for reads.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:27:59 +02:00
Christoph Hellwig
03793cbbc8 btrfs: add fast path for single device io in __btrfs_map_block
There is no need for most of the btrfs_io_context when doing I/O to a
single device.  To support such I/O without the extra btrfs_io_context
allocation, turn the mirror_num argument into a pointer so that it can
be used to output the selected mirror number, and add an optional
argument that points to a btrfs_io_stripe structure, which will be
filled with a single extent if provided by the caller.

In that case the btrfs_io_context allocation can be skipped as all
information for the single device I/O is provided in the mirror_num
argument and the on-stack btrfs_io_stripe.  A caller that makes use of
this new argument will be added in the next commit.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:27:59 +02:00
Christoph Hellwig
28793b194e btrfs: decide bio cloning inside submit_stripe_bio
Remove the orig_bio argument as it can be derived from the bioc, and
the clone argument as it can be calculated from bioc and dev_nr.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:27:59 +02:00
Christoph Hellwig
32747c4455 btrfs: factor out low-level bio setup from submit_stripe_bio
Split out a low-level btrfs_submit_dev_bio helper that just submits
the bio without any cloning decisions or setting up the end I/O handler
for future reuse by a different caller.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:27:59 +02:00
Christoph Hellwig
917f32a235 btrfs: give struct btrfs_bio a real end_io handler
Currently btrfs_bio end I/O handling is a bit of a mess.  The bi_end_io
handler and bi_private pointer of the embedded struct bio are both used
to handle the completion of the high-level btrfs_bio and for the I/O
completion for the low-level device that the embedded bio ends up being
sent to.

To support this bi_end_io and bi_private are saved into the
btrfs_io_context structure and then restored after the bio sent to the
underlying device has completed the actual I/O.

Untangle this by adding an end I/O handler and private data to struct
btrfs_bio for the high-level btrfs_bio based completions, and leave the
actual bio bi_end_io handler and bi_private pointer entirely to the
low-level device I/O.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:27:59 +02:00
Christoph Hellwig
f1c2937976 btrfs: properly abstract the parity raid bio handling
The parity raid write/recover functionality is currently not very well
abstracted from the bio submission and completion handling in volumes.c:

 - the raid56 code directly completes the original btrfs_bio fed into
   btrfs_submit_bio instead of dispatching back to volumes.c
 - the raid56 code consumes the bioc and bio_counter references taken
   by volumes.c, which also leads to special casing of the calls from
   the scrub code into the raid56 code

To fix this up supply a bi_end_io handler that calls back into the
volumes.c machinery, which then puts the bioc, decrements the bio_counter
and completes the original bio, and updates the scrub code to also
take ownership of the bioc and bio_counter in all cases.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:27:59 +02:00
Christoph Hellwig
c3a62baf21 btrfs: use chained bios when cloning
The stripes_pending in the btrfs_io_context counts number of inflight
low-level bios for an upper btrfs_bio.  For reads this is generally
one as reads are never cloned, while for writes we can trivially use
the bio remaining mechanisms that is used for chained bios.

To be able to make use of that mechanism, split out a separate trivial
end_io handler for the cloned bios that does a minimal amount of error
tracking and which then calls bio_endio on the original bio to transfer
control to that, with the remaining counter making sure it is completed
last.  This then allows to merge btrfs_end_bioc into the original bio
bi_end_io handler.

To make this all work all error handling needs to happen through the
bi_end_io handler, which requires a small amount of reshuffling in
submit_stripe_bio so that the bio is cloned already by the time the
suitability of the device is checked.

This reduces the size of the btrfs_io_context and prepares splitting
the btrfs_bio at the stripe boundary.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:27:59 +02:00
Christoph Hellwig
2bbc72f14f btrfs: don't take a bio_counter reference for cloned bios
Stop grabbing an extra bio_counter reference for each clone bio in a
mirrored write and instead just release the one original reference in
btrfs_end_bioc once all the bios for a single btrfs_bio have completed
instead of at the end of btrfs_submit_bio once all bios have been
submitted.

This means the reference is now carried by the "upper" btrfs_bio only
instead of each lower bio.

Also remove the now unused btrfs_bio_counter_inc_noblocked helper.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:27:58 +02:00
Christoph Hellwig
6b42f5e343 btrfs: pass the operation to btrfs_bio_alloc
Pass the operation to btrfs_bio_alloc, matching what bio_alloc_bioset
set does.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Tested-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>
2022-09-26 12:27:58 +02:00
Christoph Hellwig
d45cfb883b btrfs: move btrfs_bio allocation to volumes.c
volumes.c is the place that implements the storage layer using the
btrfs_bio structure, so move the bio_set and allocation helpers there
as well.

To make up for the new initialization boilerplate, merge the two
init/exit helpers in extent_io.c into a single one.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Tested-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>
2022-09-26 12:27:58 +02:00
Josef Bacik
588a486835 btrfs: remove lock protection for BLOCK_GROUP_FLAG_RELOCATING_REPAIR
Before when this was modifying the bit field we had to protect it with
the bg->lock, however now we're using bit helpers so we can stop
using the bg->lock.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:27:54 +02:00
Josef Bacik
9283b9e09a btrfs: remove lock protection for BLOCK_GROUP_FLAG_TO_COPY
We use this during device replace for zoned devices, we were simply
taking the lock because it was in a bit field and we needed the lock to
be safe with other modifications in the bitfield.  With the bit helpers
we no longer require that locking.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:27:54 +02:00
Josef Bacik
3349b57fd4 btrfs: convert block group bit field to use bit helpers
We use a bit field in the btrfs_block_group for different flags, however
this is awkward because we have to hold the block_group->lock for any
modification of any of these fields, and makes the code clunky for a few
of these flags.  Convert these to a properly flags setup so we can
utilize the bit helpers.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:27:54 +02:00
Qu Wenruo
5da431b71d btrfs: fix the max chunk size and stripe length calculation
[BEHAVIOR CHANGE]
Since commit f6fca3917b ("btrfs: store chunk size in space-info
struct"), btrfs no longer can create larger data chunks than 1G:

  mkfs.btrfs -f -m raid1 -d raid0 $dev1 $dev2 $dev3 $dev4
  mount $dev1 $mnt

  btrfs balance start --full $mnt
  btrfs balance start --full $mnt
  umount $mnt

  btrfs ins dump-tree -t chunk $dev1 | grep "DATA|RAID0" -C 2

Before that offending commit, what we got is a 4G data chunk:

	item 6 key (FIRST_CHUNK_TREE CHUNK_ITEM 9492758528) itemoff 15491 itemsize 176
		length 4294967296 owner 2 stripe_len 65536 type DATA|RAID0
		io_align 65536 io_width 65536 sector_size 4096
		num_stripes 4 sub_stripes 1

Now what we got is only 1G data chunk:

	item 6 key (FIRST_CHUNK_TREE CHUNK_ITEM 6271533056) itemoff 15491 itemsize 176
		length 1073741824 owner 2 stripe_len 65536 type DATA|RAID0
		io_align 65536 io_width 65536 sector_size 4096
		num_stripes 4 sub_stripes 1

This will increase the number of data chunks by the number of devices,
not only increase system chunk usage, but also greatly increase mount
time.

Without a proper reason, we should not change the max chunk size.

[CAUSE]
Previously, we set max data chunk size to 10G, while max data stripe
length to 1G.

Commit f6fca3917b ("btrfs: store chunk size in space-info struct")
completely ignored the 10G limit, but use 1G max stripe limit instead,
causing above shrink in max data chunk size.

[FIX]
Fix the max data chunk size to 10G, and in decide_stripe_size_regular()
we limit stripe_size to 1G manually.

This should only affect data chunks, as for metadata chunks we always
set the max stripe size the same as max chunk size (256M or 1G
depending on fs size).

Now the same script result the same old result:

	item 6 key (FIRST_CHUNK_TREE CHUNK_ITEM 9492758528) itemoff 15491 itemsize 176
		length 4294967296 owner 2 stripe_len 65536 type DATA|RAID0
		io_align 65536 io_width 65536 sector_size 4096
		num_stripes 4 sub_stripes 1

Reported-by: Wang Yugui <wangyugui@e16-tech.com>
Fixes: f6fca3917b ("btrfs: store chunk size in space-info struct")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-06 17:49:58 +02:00
Zixuan Fu
9ea0106a7a btrfs: fix possible memory leak in btrfs_get_dev_args_from_path()
In btrfs_get_dev_args_from_path(), btrfs_get_bdev_and_sb() can fail if
the path is invalid. In this case, btrfs_get_dev_args_from_path()
returns directly without freeing args->uuid and args->fsid allocated
before, which causes memory leak.

To fix these possible leaks, when btrfs_get_bdev_and_sb() fails,
btrfs_put_dev_args_from_path() is called to clean up the memory.

Reported-by: TOTE Robot <oslab@tsinghua.edu.cn>
Fixes: faa775c41d ("btrfs: add a btrfs_get_dev_args_from_path helper")
CC: stable@vger.kernel.org # 5.16
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Zixuan Fu <r33s3n6@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-08-22 18:06:33 +02:00
Christoph Hellwig
d28beb3e81 btrfs: merge btrfs_dev_stat_print_on_error with its only caller
Fold it into the only caller.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:42 +02:00
Christoph Hellwig
b9af128d1e btrfs: raid56: transfer the bio counter reference to the raid submission helpers
Transfer the bio counter reference acquired by btrfs_submit_bio to
raid56_parity_write and raid56_parity_recovery together with the bio
that the reference was acquired for instead of acquiring another
reference in those helpers and dropping the original one in
btrfs_submit_bio.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:40 +02:00
Christoph Hellwig
6065fd95da btrfs: do not return errors from raid56_parity_recover
Always consume the bio and call the end_io handler on error instead of
returning an error and letting the caller handle it.  This matches what
the block layer submission does and avoids any confusion on who
needs to handle errors.

Also use the proper bool type for the generic_io argument.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:39 +02:00
Christoph Hellwig
31683f4aae btrfs: do not return errors from raid56_parity_write
Always consume the bio and call the end_io handler on error instead of
returning an error and letting the caller handle it.  This matches what
the block layer submission does and avoids any confusion on who
needs to handle errors.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:39 +02:00
Christoph Hellwig
1a722d8f5b btrfs: do not return errors from btrfs_map_bio
Always consume the bio and call the end_io handler on error instead of
returning an error and letting the caller handle it.  This matches
what the block layer submission does and avoids any confusion on who
needs to handle errors.

As this requires touching all the callers, rename the function to
btrfs_submit_bio, which describes the functionality much better.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:39 +02:00
Qu Wenruo
462b0b2a86 btrfs: return proper mapped length for RAID56 profiles in __btrfs_map_block()
For profiles other than RAID56, __btrfs_map_block() returns @map_length
as min(stripe_end, logical + *length), which is also the same result
from btrfs_get_io_geometry().

But for RAID56, __btrfs_map_block() returns @map_length as stripe_len.

This strange behavior is going to hurt incoming bio split at
btrfs_map_bio() time, as we will use @map_length as bio split size.

Fix this behavior by returning @map_length by the same calculation as
for other profiles.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:39 +02:00
Christoph Hellwig
ff18a4afeb btrfs: raid56: use fixed stripe length everywhere
The raid56 code assumes a fixed stripe length BTRFS_STRIPE_LEN but there
are functions passing it as arguments, this is not necessary. The fixed
value has been used for a long time and though the stripe length should
be configurable by super block member stripesize, this hasn't been
implemented and would require more changes so we don't need to keep this
code around until then.

Partially based on a patch from Qu Wenruo.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
[ update changelog ]
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:39 +02:00
David Sterba
c1867eb33e btrfs: clean up chained assignments
The chained assignments may be convenient to write, but make readability
a bit worse as it's too easy to overlook that there are several values
set on the same line while this is rather an exception.  Making it
consistent everywhere avoids surprises.

The pattern where inode times are initialized reuses the first value and
the order is mtime, ctime. In other blocks the assignments are expanded
so the order of variables is similar to the neighboring code.

Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:39 +02:00
Qu Wenruo
3613249a1b btrfs: warn about dev extents that are inside the reserved range
Btrfs on-disk format has reserved the first 1MiB for the primary super
block (at 64KiB offset) and bootloaders may also use this space.

This behavior is only introduced since v4.1 btrfs-progs release,
although kernel can ensure we never touch the reserved range of super
blocks, it's better to inform the end users, and a balance will resolve
the problem.

Signed-off-by: Qu Wenruo <wqu@suse.com>
[ update changelog and message ]
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:36 +02:00
Qu Wenruo
37f85ec320 btrfs: use named constant for reserved device space
There's a reserved space on each device of size 1MiB that can be used by
bootloaders or to avoid accidental overwrite. Use a symbolic constant
with the explaining comment instead of hard coding the value and
multiple comments.

Note: since btrfs-progs v4.1, mkfs.btrfs will reserve the first 1MiB for
the primary super block (at offset 64KiB), until then the range could
have been used by mistake. Kernel has been always respecting the 1MiB
range for writes.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:36 +02:00
Qu Wenruo
6d322b4839 btrfs: use ncopies from btrfs_raid_array in btrfs_num_copies()
For all non-RAID56 profiles, we can use btrfs_raid_array[].ncopies
directly, only for RAID5 and RAID6 we need some extra handling as
there's no table value for that.

For RAID10 there's a change from sub_stripes to ncopies. The values are
the same but semantically we want to use number of copies, as this is
what btrfs_num_copies does.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:36 +02:00