linux-stable.git/drivers/md/raid1.c, branch v6.6.2

md/raid1: fix error: ISO C90 forbids mixed declarations

2023-09-11T21:41:58+00:00

There is a compile error when this commit is added:
md: raid1: fix potential OOB in raid1_remove_disk()

drivers/md/raid1.c: In function 'raid1_remove_disk':
drivers/md/raid1.c:1844:9: error: ISO C90 forbids mixed declarations
and code [-Werror=declaration-after-statement]
1844 |         struct raid1_info *p = conf->mirrors + number;
     |         ^~~~~~

That's because the new code was inserted before the struct.
The change is move the struct command above this commit.

Fixes: 8b0472b50bcf ("md: raid1: fix potential OOB in raid1_remove_disk()")
Signed-off-by: Nigel Croxon 
Signed-off-by: Song Liu 
Link: https://lore.kernel.org/r/46d929d0-2aab-4cf2-b2bf-338963e8ba5a@redhat.com

md raid1: allow writebehind to work on any leg device set WriteMostly

2023-08-18T04:11:31+00:00

As the WriteMostly flag can be set on any component device of a RAID1
array, remove the constraint that it only works if set on the first one.

Signed-off-by: Heinz Mauelshagen 
Tested-by: Xiao Ni 
Link: https://lore.kernel.org/r/2a9592bf3340f34bf588eec984b23ee219f3985e.1692013451.git.heinzm@redhat.com
Signed-off-by: Song Liu

md/raid1: hold the barrier until handle_read_error() finishes

2023-08-18T04:11:30+00:00

handle_read_error() will call allow_barrier() to match the former barrier
raising. However, it should put the allow_barrier() at the end to avoid a
concurrent raid reshape.

Fixes: 689389a06ce7 ("md/raid1: simplify handle_read_error().")
Reviewed-by: Yu Kuai 
Signed-off-by: Xueshi Hu 
Link: https://lore.kernel.org/r/20230814135356.1113639-4-xueshi.hu@smartx.com
Signed-off-by: Song Liu

md/raid1: free the r1bio before waiting for blocked rdev

2023-08-18T04:11:30+00:00

Raid1 reshape will change mempool and r1conf::raid_disks which are
needed to free r1bio. allow_barrier() make a concurrent raid1_reshape()
possible. So, free the in-flight r1bio before waiting blocked rdev.

Fixes: 6bfe0b499082 ("md: support blocking writes to an array on device failure")
Reviewed-by: Yu Kuai 
Signed-off-by: Xueshi Hu 
Link: https://lore.kernel.org/r/20230814135356.1113639-3-xueshi.hu@smartx.com
Signed-off-by: Song Liu

md/raid1: call free_r1bio() before allow_barrier() in raid_end_bio_io()

2023-08-18T04:11:30+00:00

After allow_barrier, a concurrent raid1_reshape() will replace old mempool
and r1conf::raid_disks. Move allow_barrier() to the end of raid_end_bio_io(),
so that r1bio can be freed safely.

Reviewed-by: Yu Kuai 
Signed-off-by: Xueshi Hu 
Link: https://lore.kernel.org/r/20230814135356.1113639-2-xueshi.hu@smartx.com
Signed-off-by: Song Liu

md: Hold mddev->reconfig_mutex when trying to get mddev->sync_thread

2023-08-15T16:40:26+00:00

Commit ba9d9f1a707f ("Revert "md: unlock mddev before reap sync_thread in
action_store"") removed the scenario of calling md_unregister_thread()
without holding mddev->reconfig_mutex, so add a lock holding check before
acquiring mddev->sync_thread by passing mdev to md_unregister_thread().

Signed-off-by: Li Lingfeng 
Reviewed-by: Yu Kuai 
Link: https://lore.kernel.org/r/20230803071711.2546560-1-lilingfeng@huaweicloud.com
Signed-off-by: Song Liu

md: raid1: fix potential OOB in raid1_remove_disk()

2023-08-15T16:37:27+00:00

If rddev->raid_disk is greater than mddev->raid_disks, there will be
an out-of-bounds in raid1_remove_disk(). We have already found
similar reports as follows:

1) commit d17f744e883b ("md-raid10: fix KASAN warning")
2) commit 1ebc2cec0b7d ("dm raid: fix KASAN warning in raid5_remove_disk")

Fix this bug by checking whether the "number" variable is
valid.

Signed-off-by: Zhang Shurong 
Reviewed-by: Yu Kuai 
Link: https://lore.kernel.org/r/tencent_0D24426FAC6A21B69AC0C03CE4143A508F09@qq.com
Signed-off-by: Song Liu

md/raid1: Avoid lock contention from wake_up()

2023-07-27T07:13:30+00:00

wake_up is called unconditionally in a few paths such as make_request(),
which cause lock contention under high concurrency workload like below
    raid1_end_write_request
     wake_up
      __wake_up_common_lock
       spin_lock_irqsave

Improve performance by only call wake_up() if waitqueue is not empty

Fio test script:

[global]
name=random reads and writes
ioengine=libaio
direct=1
readwrite=randrw
rwmixread=70
iodepth=64
buffered=0
filename=/dev/md0
size=1G
runtime=30
time_based
randrepeat=0
norandommap
refill_buffers
ramp_time=10
bs=4k
numjobs=400
group_reporting=1
[job1]

Test result with 2 ramdisk in raid1 on a Intel Broadwell 56 cores server.

	Before this patch       With this patch
	READ	BW=4621MB/s	BW=7337MB/s
	WRITE	BW=1980MB/s	BW=3144MB/s

The patch is inspired by Yu Kuai's change for raid10:
https://lore.kernel.org/r/20230621105728.1268542-1-yukuai1@huaweicloud.com

Cc: Yu Kuai 
Signed-off-by: Jack Wang 
Reviewed-by: Yu Kuai 
Link: https://lore.kernel.org/r/20230705113227.148494-1-jinpu.wang@ionos.com
Signed-off-by: Song Liu

md: remove redundant check in fix_read_error()

2023-07-27T07:13:30+00:00

In fix_read_error(), 'success' will be checked immediately after assigning
it, if it is set to 1 then the loop will break. Checking it again in
condition of loop is redundant. Clean it up.

Signed-off-by: Li Nan 
Reviewed-by: Yu Kuai 
Link: https://lore.kernel.org/r/20230623173236.2513554-3-linan666@huaweicloud.com
Signed-off-by: Song Liu

md/raid1: prioritize adding disk to 'removed' mirror

2023-07-27T07:13:30+00:00

New disk should be added to "removed" position first instead of to be a
replacement. Commit 6090368abcb4 ("md/raid10: prioritize adding disk to
'removed' mirror") has fixed this issue for raid10. Fix it for raid1 now.

Signed-off-by: Li Nan 
Reviewed-by: Yu Kuai 
Link: https://lore.kernel.org/r/20230627014332.3810102-1-linan666@huaweicloud.com
Signed-off-by: Song Liu