If bio is split by internal handling like chunksize or badblocks, the
corresponding trace_block_split() is missing, resulting in blktrace
inability to catch BIO split events and making it harder to analyze the
BIO sequence.
Cc: stable@vger.kernel.org
Fixes: 4b1faf9316 ("block: Kill bio_pair_split()")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, raid456 must perform a whole array initial recovery to build
initail xor data, then IO to the array won't have to read all the blocks
in underlying disks.
This behavior will affect IO performance a lot, and nowadays there are
huge disks and the initial recovery can take a long time. Hence llbitmap
will support lazy initial recovery in following patches. This method is
used to check if data blocks is synced or not, if not then IO will still
have to read all blocks for raid456.
Link: https://lore.kernel.org/linux-raid/20250829080426.1441678-9-yukuai1@huaweicloud.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
'recovery_cp' was used to represent the progress of sync, but its name
contains recovery, which can cause confusion. Replaces 'recovery_cp'
with 'resync_offset' for clarity.
Signed-off-by: Li Nan <linan122@huawei.com>
Link: https://lore.kernel.org/linux-raid/20250722033340.1933388-1-linan666@huaweicloud.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
When specified with WQ_CPU_INTENSIVE, the workqueue doesn't
participate in concurrency management. This behaviour is already
accounted for WQ_UNBOUND workqueues given that they are assigned
to their own worker threads.
Unset WQ_CPU_INTENSIVE as the use of flag has no effect when
used with WQ_UNBOUND.
Signed-off-by: Ryo Takakura <ryotkkr98@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/linux-raid/20250601013702.64640-1-ryotkkr98@gmail.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
During code review, it's found that other than raid5_bitmap_sector(),
reshape_progress is always checked before get_reshape_loc(), while
raid5_bitmap_sector() should check as well to prevent holding the
lock 'conf->device_lock'. Hence merge that checking inside
get_reshape_loc().
Link: https://lore.kernel.org/linux-raid/20250227120452.808503-1-yukuai1@huaweicloud.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
There are two BUG reports that raid5 will hang at
bitmap_startwrite([1],[2]), root cause is that bitmap start write and end
write is unbalanced, it's not quite clear where, and while reviewing raid5
code, it's found that bitmap operations can be optimized. For example,
for a 4 disks raid5, with chunksize=8k, if user issue a IO (0 + 48k) to
the array:
┌────────────────────────────────────────────────────────────┐
│chunk 0 │
│ ┌────────────┬─────────────┬─────────────┬────────────┼
│ sh0 │A0: 0 + 4k │A1: 8k + 4k │A2: 16k + 4k │A3: P │
│ ┼────────────┼─────────────┼─────────────┼────────────┼
│ sh1 │B0: 4k + 4k │B1: 12k + 4k │B2: 20k + 4k │B3: P │
┼──────┴────────────┴─────────────┴─────────────┴────────────┼
│chunk 1 │
│ ┌────────────┬─────────────┬─────────────┬────────────┤
│ sh2 │C0: 24k + 4k│C1: 32k + 4k │C2: P │C3: 40k + 4k│
│ ┼────────────┼─────────────┼─────────────┼────────────┼
│ sh3 │D0: 28k + 4k│D1: 36k + 4k │D2: P │D3: 44k + 4k│
└──────┴────────────┴─────────────┴─────────────┴────────────┘
Before this patch, 4 stripe head will be used, and each sh will attach
bio for 3 disks, and each attached bio will trigger
bitmap_startwrite() once, which means total 12 times.
- 3 times (0 + 4k), for (A0, A1 and A2)
- 3 times (4 + 4k), for (B0, B1 and B2)
- 3 times (8 + 4k), for (C0, C1 and C3)
- 3 times (12 + 4k), for (D0, D1 and D3)
After this patch, md upper layer will calculate that IO range (0 + 48k)
is corresponding to the bitmap (0 + 16k), and call bitmap_startwrite()
just once.
Noted that this patch will align bitmap ranges to the chunks, for example,
if user issue a IO (0 + 4k) to array:
- Before this patch, 1 time (0 + 4k), for A0;
- After this patch, 1 time (0 + 8k) for chunk 0;
Usually, one bitmap bit will represent more than one disk chunk, and this
doesn't have any difference. And even if user really created a array
that one chunk contain multiple bits, the overhead is that more data
will be recovered after power failure.
Also remove STRIPE_BITMAP_PENDING since it's not used anymore.
[1] https://lore.kernel.org/all/CAJpMwyjmHQLvm6zg1cmQErttNNQPDAAXPKM3xgTjMhbfts986Q@mail.gmail.com/
[2] https://lore.kernel.org/all/ADF7D720-5764-4AF3-B68E-1845988737AA@flyingcircus.io/
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20250109015145.158868-6-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
Bitmap is used for the whole array for raid1/raid10, hence IO for the
array can be used directly for bitmap. However, bitmap is used for
underlying disks for raid5, hence IO for the array can't be used
directly for bitmap.
Implement pers->bitmap_sector() for raid5 to convert IO ranges from the
array to the underlying disks.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20250109015145.158868-5-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
For the case that IO failed for one rdev, the bit will be mark as NEEDED
in following cases:
1) If badblocks is set and rdev is not faulty;
2) If rdev is faulty;
Case 1) is useless because synchronize data to badblocks make no sense.
Case 2) can be replaced with mddev->degraded.
Also remove R1BIO_Degraded, R10BIO_Degraded and STRIPE_DEGRADED since
case 2) no longer use them.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20250109015145.158868-3-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
behind_write is only used in raid1, prepare to refactor
bitmap_{start/end}write(), there are no functional changes.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Link: https://lore.kernel.org/r/20250109015145.158868-2-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
One customer reports a bug: raid5 is hung when changing thread cnt
while resync is running. The stripes are all in conf->handle_list
and new threads can't handle them.
Commit b39f35ebe8 ("md: don't quiesce in mddev_suspend()") removes
pers->quiesce from mddev_suspend/resume. Before this patch, mddev_suspend
needs to wait for all ios including sync io to finish. Now it's used
to only wait normal io.
Fix this by calling raid5_quiesce from raid5_store_group_thread_cnt
directly to wait all sync requests to finish before changing the group
cnt.
Fixes: b39f35ebe8 ("md: don't quiesce in mddev_suspend()")
Cc: stable@vger.kernel.org
Signed-off-by: Xiao Ni <xni@redhat.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20241106095124.74577-1-xni@redhat.com
Signed-off-by: Song Liu <song@kernel.org>
Faulty rdev should never be accessed anymore, hence there is no point to
wait for bad block to be acknowledged in this case while handling write
request.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Tested-by: Mariusz Tkaczyk <mariusz.tkaczyk@linux.intel.com>
Link: https://lore.kernel.org/r/20241031033114.3845582-8-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
Now that actual overlaps are not handled on the wait_for_overlap wq
anymore, the remaining cases when we wait on this wq are limited to
reshape. If reshape is not in progress, don't add to the wq in
raid5_make_request() because add_wait_queue() / remove_wait_queue()
operations take a spinlock and cause noticeable contention when multiple
threads are submitting requests to the mddev.
Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Link: https://lore.kernel.org/r/20240827153536.6743-3-artur.paszkiewicz@intel.com
Signed-off-by: Song Liu <song@kernel.org>
And move the condition "if (mddev->bitmap)" into md_bitmap_resize() as
well, on the one hand make code cleaner, on the other hand try not to
access bitmap directly.
Since we are here, also change the parameter 'init' from int to bool.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240826074452.1490072-35-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
Add a parameter 'bool sync' to distinguish them, and
md_bitmap_unplug_async() won't be exported anymore, hence
bitmap_operations only need one op to cover them.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240826074452.1490072-32-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
So that the implementation won't be exposed, and it'll be possible
to invent a new bitmap by replacing bitmap_operations.
Also change the parameter from bitmap to mddev, to avoid access
bitmap outside md-bitmap.c as much as possible.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240826074452.1490072-30-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
So that the implementation won't be exposed, and it'll be possible
to invent a new bitmap by replacing bitmap_operations.
Also change the parameter from bitmap to mddev, to avoid access
bitmap outside md-bitmap.c as much as possible.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240826074452.1490072-29-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
So that the implementation won't be exposed, and it'll be possible
to invent a new bitmap by replacing bitmap_operations.
Also change the parameter from bitmap to mddev, to avoid access
bitmap outside md-bitmap.c as much as possible.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240826074452.1490072-28-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
For internal callers, aborted are always set to false, while for
external callers, aborted are always set to true.
Hence there is no need to always pass in true for exported api.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240826074452.1490072-27-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
So that the implementation won't be exposed, and it'll be possible
to invent a new bitmap by replacing bitmap_operations.
Also change the parameter from bitmap to mddev, to avoid access
bitmap outside md-bitmap.c as much as possible.
Also fix lots of code style.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240826074452.1490072-26-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
So that the implementation won't be exposed, and it'll be possible
to invent a new bitmap by replacing bitmap_operations.
Also change the parameter from bitmap to mddev, to avoid access
bitmap outside md-bitmap.c as much as possible. And change the type
of 'success' and 'behind' from int to bool.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240826074452.1490072-25-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
So that the implementation won't be exposed, and it'll be possible
to invent a new bitmap by replacing bitmap_operations.
Also change the parameter from bitmap to mddev, to avoid access
bitmap outside md-bitmap.c as much as possible. And change the type
of 'behind' from int to bool.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240826074452.1490072-24-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
When handling an IO request, MD checks if a reshape is currently
happening, and if so, where the IO sector is in relation to the reshape
progress. MD uses conf->reshape_progress for both of these tasks. When
the reshape finishes, conf->reshape_progress is set to MaxSector. If
this occurs after MD checks if the reshape is currently happening but
before it calls ahead_of_reshape(), then ahead_of_reshape() will end up
comparing the IO sector against MaxSector. During a backwards reshape,
this will make MD think the IO sector is in the area not yet reshaped,
causing it to use the previous configuration, and map the IO to the
sector where that data was before the reshape.
This bug can be triggered by running the lvm2
lvconvert-raid-reshape-linear_to_raid6-single-type.sh test in a loop,
although it's very hard to reproduce.
Fix this by factoring the code that checks where the IO sector is in
relation to the reshape out to a helper called get_reshape_loc(),
which reads reshape_progress and reshape_safe while holding the
device_lock, and then rechecks if the reshape has finished before
calling ahead_of_reshape with the saved values.
Also use the helper during the REQ_NOWAIT check to see if the location
is inside of the reshape region.
Fixes: fef9c61fdf ("md/raid5: change reshape-progress measurement to cope with reshaping backwards.")
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240702151802.1632010-1-bmarzins@redhat.com
The md driver wants to enforce a number of flags for all devices, even
when not inheriting them from the underlying devices. To make sure these
flags survive the queue_limits_set calls that md uses to update the
queue limits without deriving them form the previous limits add a new
md_init_stacking_limits helper that calls blk_set_stacking_limits and sets
these flags.
Fixes: 1122c0c1cc ("block: move cache control settings out of queue->flags")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240626142637.300624-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Merge in queue limits cleanups.
* for-6.11/block-limits:
block: move the raid_partial_stripes_expensive flag into the features field
block: remove the discard_alignment flag
block: move the misaligned flag into the features field
block: renumber and rename the cache disabled flag
block: fix spelling and grammar for in writeback_cache_control.rst
block: remove the unused blk_bounce enum
Move the raid_partial_stripes_expensive flags into the features field to
reclaim a little bit of space.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20240619154623.450048-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Merge in last round of queue limits changes from Christoph.
* for-6.11/block-limits: (26 commits)
block: move the bounce flag into the features field
block: move the skip_tagset_quiesce flag to queue_limits
block: move the pci_p2pdma flag to queue_limits
block: move the zone_resetall flag to queue_limits
block: move the zoned flag into the features field
block: move the poll flag to queue_limits
block: move the dax flag to queue_limits
block: move the nowait flag to queue_limits
block: move the synchronous flag to queue_limits
block: move the stable_writes flag to queue_limits
block: move the io_stat flag setting to queue_limits
block: move the add_random flag to queue_limits
block: move the nonrot flag to queue_limits
block: move cache control settings out of queue->flags
block: remove blk_flush_policy
block: freeze the queue in queue_attr_store
nbd: move setting the cache control flags to __nbd_set_size
virtio_blk: remove virtblk_update_cache_mode
loop: fold loop_update_rotational into loop_reconfigure_limits
loop: also use the default block size from an underlying block device
...
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move the stable_writes flag into the queue_limits feature field so that
it can be set atomically with the queue frozen.
The flag is now inherited by blk_stack_limits, which greatly simplifies
the code in dm, and fixed md which previously did not pass on the flag
set on lower devices.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240617060532.127975-18-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull in block limits branch, which exists as a shared branch for both
the block and SCSI tree.
* for-6.11/block-limits: (26 commits)
block: move integrity information into queue_limits
block: invert the BLK_INTEGRITY_{GENERATE,VERIFY} flags
block: bypass the STABLE_WRITES flag for protection information
block: don't require stable pages for non-PI metadata
block: use kstrtoul in flag_store
block: factor out flag_{store,show} helper for integrity
block: remove the blk_flush_integrity call in blk_integrity_unregister
block: remove the blk_integrity_profile structure
dm-integrity: use the nop integrity profile
md/raid1: don't free conf on raid0_run failure
md/raid0: don't free conf on raid0_run failure
block: initialize integrity buffer to zero before writing it to media
block: add special APIs for run-time disabling of discard and friends
block: remove unused queue limits API
sr: convert to the atomic queue limits API
sd: convert to the atomic queue limits API
sd: cleanup zoned queue limits initialization
sd: factor out a sd_discard_mode helper
sd: simplify the disable case in sd_config_discard
sd: add a sd_disable_write_same helper
...
Move the integrity information into the queue limits so that it can be
set atomically with other queue limits, and that the sysfs changes to
the read_verify and write_generate flags are properly synchronized.
This also allows to provide a more useful helper to stack the integrity
fields, although it still is separate from the main stacking function
as not all stackable devices want to inherit the integrity settings.
Even with that it greatly simplifies the code in md and dm.
Note that the integrity field is moved as-is into the queue limits.
While there are good arguments for removing the separate blk_integrity
structure, this would cause a lot of churn and might better be done at a
later time if desired. However the integrity field in the queue_limits
structure is now unconditional so that various ifdefs can be avoided or
replaced with IS_ENABLED(). Given that tiny size of it that seems like
a worthwhile trade off.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240613084839.1044015-13-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, mdadm support --revert-reshape to abort the reshape while
reassembling, as the test 07revert-grow. However, following BUG_ON()
can be triggerred by the test:
kernel BUG at drivers/md/raid5.c:6278!
invalid opcode: 0000 [#1] PREEMPT SMP PTI
irq event stamp: 158985
CPU: 6 PID: 891 Comm: md0_reshape Not tainted 6.9.0-03335-g7592a0b0049a #94
RIP: 0010:reshape_request+0x3f1/0xe60
Call Trace:
<TASK>
raid5_sync_request+0x43d/0x550
md_do_sync+0xb7a/0x2110
md_thread+0x294/0x2b0
kthread+0x147/0x1c0
ret_from_fork+0x59/0x70
ret_from_fork_asm+0x1a/0x30
</TASK>
Root cause is that --revert-reshape update the raid_disks from 5 to 4,
while reshape position is still set, and after reassembling the array,
reshape position will be read from super block, then during reshape the
checking of 'writepos' that is caculated by old reshape position will
fail.
Fix this panic the easy way first, by converting the BUG_ON() to
WARN_ON(), and stop the reshape if checkings fail.
Noted that mdadm must fix --revert-shape as well, and probably md/raid
should enhance metadata validation as well, however this means
reassemble will fail and there must be user tools to fix the wrong
metadata.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240611132251.1967786-13-yukuai1@huaweicloud.com
For different sync_action, sync_thread will use different max_sectors,
see details in md_sync_max_sectors(), currently both md_do_sync() and
pers->sync_request() in eatch iteration have to get the same
max_sectors. Hence pass in max_sectors for pers->sync_request() to
prevent redundant code.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240611132251.1967786-12-yukuai1@huaweicloud.com
Commit cc27b0c78c ("md: fix deadlock between mddev_suspend() and
md_write_start()") aborted md_write_start() with false when mddev is
suspended, which fixed a deadlock if calling mddev_suspend() with
holding reconfig_mutex(). Since mddev_suspend() now includes
lockdep_assert_not_held(), it no longer holds the reconfig_mutex. This
makes previous abort unnecessary. Now, remove unnecessary abort and
change function return value to void.
Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240525185257.3896201-2-linan666@huaweicloud.com
Xiao reported that lvm2 test lvconvert-raid-takeover.sh can hang with
small possibility, the root cause is exactly the same as commit
bed9e27baf ("Revert "md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d"")
However, Dan reported another hang after that, and junxiao investigated
the problem and found out that this is caused by plugged bio can't issue
from raid5d().
Current implementation in raid5d() has a weird dependence:
1) md_check_recovery() from raid5d() must hold 'reconfig_mutex' to clear
MD_SB_CHANGE_PENDING;
2) raid5d() handles IO in a deadloop, until all IO are issued;
3) IO from raid5d() must wait for MD_SB_CHANGE_PENDING to be cleared;
This behaviour is introduce before v2.6, and for consequence, if other
context hold 'reconfig_mutex', and md_check_recovery() can't update
super_block, then raid5d() will waste one cpu 100% by the deadloop, until
'reconfig_mutex' is released.
Refer to the implementation from raid1 and raid10, fix this problem by
skipping issue IO if MD_SB_CHANGE_PENDING is still set after
md_check_recovery(), daemon thread will be woken up when 'reconfig_mutex'
is released. Meanwhile, the hang problem will be fixed as well.
Fixes: 5e2cf333b7 ("md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d")
Cc: stable@vger.kernel.org # v5.19+
Reported-and-tested-by: Dan Moulding <dan@danm.net>
Closes: https://lore.kernel.org/all/20240123005700.9302-1-dan@danm.net/
Investigated-by: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240322081005.1112401-1-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
Just use the request_queue from the gendisk pointer in the relatively
few places that sill need it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed--by: Song Liu <song@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240303140150.5435-11-hch@lst.de
Build the queue limits outside the queue and apply them using
queue_limits_set. To make the code more obvious also split the queue
limits handling into separate helpers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed--by: Song Liu <song@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240303140150.5435-8-hch@lst.de
Add a helper to check for a DM-mapped MD device instead of using
the obfuscated ->gendisk or ->queue NULL checks.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed--by: Song Liu <song@kernel.org>
Tested-by: Song Liu <song@kernel.org>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240303140150.5435-4-hch@lst.de
Yu Kuai
Li Nan
Ryo Takakura
Xiao Ni
Artur Paszkiewicz
Benjamin Marzinski
Christoph Hellwig
Jens Axboe
Linus Torvalds