linux-stable.git/drivers/md/md.h, branch linux-6.2.y

md: mark md_kick_rdev_from_array static

2022-12-02T19:21:01+00:00

md_kick_rdev_from_array is only used in md.c, so unexport it and mark
the symbol static.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Song Liu

md: return the allocated devices from md_alloc

2022-08-02T23:22:46+00:00

Two callers of md_alloc want to use the newly allocated devices, so
return it instead of letting them find it cumbersomely after the
allocation.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Hannes Reinecke 
Reviewed-and-tested-by: Logan Gunthorpe 
Signed-off-by: Song Liu 
Signed-off-by: Jens Axboe

md: only delete entries from all_mddevs when the disk is freed

2022-08-02T23:22:44+00:00

This ensures device names don't get prematurely reused.  Instead add a
deleted flag to skip already deleted devices in mddev_get and other
places that only want to see live mddevs.

Reported-by: Logan Gunthorpe 
Signed-off-by: Christoph Hellwig 
Reviewed-by: Hannes Reinecke 
Reviewed-by: Logan Gunthorpe 
Signed-off-by: Song Liu 
Signed-off-by: Jens Axboe

md: Explicitly create command-line configured devices

2022-08-02T23:14:40+00:00

Boot-time assembly of arrays with md= command-line arguments breaks when
CONFIG_BLOCK_LEGACY_AUTOLOAD is unset. md_setup_drive() in md-autodetect.c
calls blkdev_get_by_dev(), assuming this implicitly creates the block
device.

Fix this by attempting to md_alloc() the array first. As in the probe path,
ignore any error as failure is caught by blkdev_get_by_dev() anyway.

Signed-off-by: Chris Webb 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Song Liu 
Signed-off-by: Jens Axboe

md: Use enum for overloaded magic numbers used by mddev->curr_resync

2022-08-02T23:14:40+00:00

Comments in the code document special values used for
mddev->curr_resync. Make this clearer by using an enum to label these
values.

The only functional change is a couple places use the wrong comparison
operator that implied 3 is another special value. They are all
fixed to imply that 3 or greater is an active resync.

Signed-off-by: Logan Gunthorpe 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Song Liu 
Signed-off-by: Jens Axboe

md/core: Combine two sync_page_io() arguments

2022-07-14T18:14:31+00:00

Improve uniformity in the kernel of handling of request operation and
flags by passing these as a single argument.

Cc: Song Liu 
Signed-off-by: Bart Van Assche 
Link: https://lore.kernel.org/r/20220714180729.1065367-32-bvanassche@acm.org
Signed-off-by: Jens Axboe

Revert "md: don't unregister sync_thread with reconfig_mutex held"

2022-06-15T17:30:14+00:00

The 07reshape5intr test is broke because of below path.

    md_reap_sync_thread
            -> mddev_unlock
            -> md_unregister_thread(&mddev->sync_thread)

And md_check_recovery is triggered by,

mddev_unlock -> md_wakeup_thread(mddev->thread)

then mddev->reshape_position is set to MaxSector in raid5_finish_reshape
since MD_RECOVERY_INTR is cleared in md_check_recovery, which means
feature_map is not set with MD_FEATURE_RESHAPE_ACTIVE and superblock's
reshape_position can't be updated accordingly.

Fixes: 8b48ec23cc51a ("md: don't unregister sync_thread with reconfig_mutex held")
Reported-by: Logan Gunthorpe 
Signed-off-by: Guoqing Jiang 
Signed-off-by: Song Liu

md: don't unregister sync_thread with reconfig_mutex held

2022-05-23T06:07:21+00:00

Unregister sync_thread doesn't need to hold reconfig_mutex since it
doesn't reconfigure array.

And it could cause deadlock problem for raid5 as follows:

1. process A tried to reap sync thread with reconfig_mutex held after echo
   idle to sync_action.
2. raid5 sync thread was blocked if there were too many active stripes.
3. SB_CHANGE_PENDING was set (because of write IO comes from upper layer)
   which causes the number of active stripes can't be decreased.
4. SB_CHANGE_PENDING can't be cleared since md_check_recovery was not able
   to hold reconfig_mutex.

More details in the link:
https://lore.kernel.org/linux-raid/5ed54ffc-ce82-bf66-4eff-390cb23bc1ac@molgen.mpg.de/T/#t

And add one parameter to md_reap_sync_thread since it could be called by
dm-raid which doesn't hold reconfig_mutex.

Reported-and-tested-by: Donald Buczek 
Signed-off-by: Guoqing Jiang 
Signed-off-by: Song Liu

md: Set MD_BROKEN for RAID1 and RAID10

2022-04-25T21:00:34+00:00

There is no direct mechanism to determine raid failure outside
personality. It is done by checking rdev->flags after executing
md_error(). If "faulty" flag is not set then -EBUSY is returned to
userspace. -EBUSY means that array will be failed after drive removal.

Mdadm has special routine to handle the array failure and it is executed
if -EBUSY is returned by md.

There are at least two known reasons to not consider this mechanism
as correct:
1. drive can be removed even if array will be failed[1].
2. -EBUSY seems to be wrong status. Array is not busy, but removal
   process cannot proceed safe.

-EBUSY expectation cannot be removed without breaking compatibility
with userspace. In this patch first issue is resolved by adding support
for MD_BROKEN flag for RAID1 and RAID10. Support for RAID456 is added in
next commit.

The idea is to set the MD_BROKEN if we are sure that raid is in failed
state now. This is done in each error_handler(). In md_error() MD_BROKEN
flag is checked. If is set, then -EBUSY is returned to userspace.

As in previous commit, it causes that #mdadm --set-faulty is able to
fail array. Previously proposed workaround is valid if optional
functionality[1] is disabled.

[1] commit 9a567843f7ce("md: allow last device to be forcibly removed from
    RAID1/RAID10.")

Reviewd-by: Xiao Ni 
Signed-off-by: Mariusz Tkaczyk 
Signed-off-by: Song Liu

scsi: md: Remove WRITE_SAME support

2022-02-23T02:11:08+00:00

There are no more end-users of REQ_OP_WRITE_SAME left, so we can start
deleting it.

Link: https://lore.kernel.org/r/20220209082828.2629273-6-hch@lst.de
Signed-off-by: Christoph Hellwig 
Signed-off-by: Martin K. Petersen