dm raid: fix false -EBUSY when handling check/repair message

[ Upstream commit 74694bcb ]

Sending a check/repair message infrequently leads to -EBUSY instead of
properly identifying an active resync.  This occurs because
raid_message() is testing recovery bits in a racy way.

Fix by calling decipher_sync_action() from raid_message() to properly
identify the idle state of the RAID device.
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/md/dm-raid.c

@@ -3690,8 +3690,7 @@ static int raid_message(struct dm_target *ti, unsigned int argc, char **argv,
 			set_bit(MD_RECOVERY_INTR, &mddev->recovery);
 			md_reap_sync_thread(mddev);
 		}
-	} else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
-		   test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
+	} else if (decipher_sync_action(mddev, mddev->recovery) != st_idle)
 		return -EBUSY;
 	else if (!strcasecmp(argv[0], "resync"))
 		; /* MD_RECOVERY_NEEDED set below */