dm: set DMF_SUSPENDED* _before_ clearing DMF_NOFLUSH_SUSPENDING
Otherwise, there is potential for both DMF_SUSPENDED* and
DMF_NOFLUSH_SUSPENDING to not be set during dm_suspend() -- which is
definitely _not_ a valid state.
This fix, in conjuction with "dm rq: fix the starting and stopping of
blk-mq queues", addresses the potential for request-based DM multipath's
__multipath_map() to see !dm_noflush_suspending() during suspend.
Reported-by: Bart Van Assche <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>
Cc: [email protected]
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 25d1d97..dfa09e1 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -2082,7 +2082,8 @@
* Caller must hold md->suspend_lock
*/
static int __dm_suspend(struct mapped_device *md, struct dm_table *map,
- unsigned suspend_flags, int interruptible)
+ unsigned suspend_flags, int interruptible,
+ int dmf_suspended_flag)
{
bool do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG;
bool noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG;
@@ -2149,6 +2150,8 @@
* to finish.
*/
r = dm_wait_for_completion(md, interruptible);
+ if (!r)
+ set_bit(dmf_suspended_flag, &md->flags);
if (noflush)
clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags);
@@ -2210,12 +2213,10 @@
map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock));
- r = __dm_suspend(md, map, suspend_flags, TASK_INTERRUPTIBLE);
+ r = __dm_suspend(md, map, suspend_flags, TASK_INTERRUPTIBLE, DMF_SUSPENDED);
if (r)
goto out_unlock;
- set_bit(DMF_SUSPENDED, &md->flags);
-
dm_table_postsuspend_targets(map);
out_unlock:
@@ -2309,9 +2310,8 @@
* would require changing .presuspend to return an error -- avoid this
* until there is a need for more elaborate variants of internal suspend.
*/
- (void) __dm_suspend(md, map, suspend_flags, TASK_UNINTERRUPTIBLE);
-
- set_bit(DMF_SUSPENDED_INTERNALLY, &md->flags);
+ (void) __dm_suspend(md, map, suspend_flags, TASK_UNINTERRUPTIBLE,
+ DMF_SUSPENDED_INTERNALLY);
dm_table_postsuspend_targets(map);
}
