dm raid: fix deadlock caused by premature md_stop_writes()

md_stop_writes() is called in raid_presuspend() causing deadlocks on
bios submitted afterwards -- which happens on loaded raid sets with
conversion requests.

Fix by moving md_stop_writes() to raid_postsuspend().  NOTE: when the
recovery's frozen (MD_RECOVERY_FROZEN), writes haven't been started (or
are already stopped) so don't stop them again.

Also remove superfluous readonly setting.

Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This commit is contained in:
Heinz Mauelshagen 2017-12-02 01:03:48 +01:00 committed by Mike Snitzer
parent fbc7c07ec2
commit 1af2048a3e

View File

@ -3613,24 +3613,19 @@ static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits)
blk_limits_io_opt(limits, chunk_size * mddev_data_stripes(rs));
}
static void raid_presuspend(struct dm_target *ti)
{
struct raid_set *rs = ti->private;
md_stop_writes(&rs->md);
}
static void raid_postsuspend(struct dm_target *ti)
{
struct raid_set *rs = ti->private;
if (!test_and_set_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags)) {
/* Writes have to be stopped before suspending to avoid deadlocks. */
if (!test_bit(MD_RECOVERY_FROZEN, &rs->md.recovery))
md_stop_writes(&rs->md);
mddev_lock_nointr(&rs->md);
mddev_suspend(&rs->md);
mddev_unlock(&rs->md);
}
rs->md.ro = 1;
}
static void attempt_restore_of_faulty_devices(struct raid_set *rs)
@ -3903,7 +3898,6 @@ static struct target_type raid_target = {
.message = raid_message,
.iterate_devices = raid_iterate_devices,
.io_hints = raid_io_hints,
.presuspend = raid_presuspend,
.postsuspend = raid_postsuspend,
.preresume = raid_preresume,
.resume = raid_resume,