Merge tag 'md/3.13-fixes' of git://neil.brown.name/md

Pull late md fixes from Neil Brown:
 "Half a dozen md bug fixes.

  All of these fix real bugs the people have hit, and are tagged for
  -stable.  Sorry they are late ....  Christmas holidays and all that.
  Hopefully they can still squeak into 3.13"

* tag 'md/3.13-fixes' of git://neil.brown.name/md:
  md: fix problem when adding device to read-only array with bitmap.
  md/raid10: fix bug when raid10 recovery fails to recover a block.
  md/raid5: fix a recently broken BUG_ON().
  md/raid1: fix request counting bug in new 'barrier' code.
  md/raid10: fix two bugs in handling of known-bad-blocks.
  md/raid5: Fix possible confusion when multiple write errors occur.

1 files changed, 15 insertions, 3 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 21f4d7ff0da2..369d919bdafe 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -1077,6 +1077,7 @@ static int super_90_validate(struct mddev *mddev, struct md_rdev *rdev)
 	rdev->raid_disk = -1;
 	clear_bit(Faulty, &rdev->flags);
 	clear_bit(In_sync, &rdev->flags);
+	clear_bit(Bitmap_sync, &rdev->flags);
 	clear_bit(WriteMostly, &rdev->flags);
 
 	if (mddev->raid_disks == 0) {
@@ -1155,6 +1156,8 @@ static int super_90_validate(struct mddev *mddev, struct md_rdev *rdev)
 		 */
 		if (ev1 < mddev->bitmap->events_cleared)
 			return 0;
+		if (ev1 < mddev->events)
+			set_bit(Bitmap_sync, &rdev->flags);
 	} else {
 		if (ev1 < mddev->events)
 			/* just a hot-add of a new device, leave raid_disk at -1 */
@@ -1563,6 +1566,7 @@ static int super_1_validate(struct mddev *mddev, struct md_rdev *rdev)
 	rdev->raid_disk = -1;
 	clear_bit(Faulty, &rdev->flags);
 	clear_bit(In_sync, &rdev->flags);
+	clear_bit(Bitmap_sync, &rdev->flags);
 	clear_bit(WriteMostly, &rdev->flags);
 
 	if (mddev->raid_disks == 0) {
@@ -1645,6 +1649,8 @@ static int super_1_validate(struct mddev *mddev, struct md_rdev *rdev)
 		 */
 		if (ev1 < mddev->bitmap->events_cleared)
 			return 0;
+		if (ev1 < mddev->events)
+			set_bit(Bitmap_sync, &rdev->flags);
 	} else {
 		if (ev1 < mddev->events)
 			/* just a hot-add of a new device, leave raid_disk at -1 */
@@ -2788,6 +2794,7 @@ slot_store(struct md_rdev *rdev, const char *buf, size_t len)
 		else
 			rdev->saved_raid_disk = -1;
 		clear_bit(In_sync, &rdev->flags);
+		clear_bit(Bitmap_sync, &rdev->flags);
 		err = rdev->mddev->pers->
 			hot_add_disk(rdev->mddev, rdev);
 		if (err) {
@@ -5760,6 +5767,7 @@ static int add_new_disk(struct mddev * mddev, mdu_disk_info_t *info)
 			    info->raid_disk < mddev->raid_disks) {
 				rdev->raid_disk = info->raid_disk;
 				set_bit(In_sync, &rdev->flags);
+				clear_bit(Bitmap_sync, &rdev->flags);
 			} else
 				rdev->raid_disk = -1;
 		} else
@@ -7706,7 +7714,8 @@ static int remove_and_add_spares(struct mddev *mddev,
 		if (test_bit(Faulty, &rdev->flags))
 			continue;
 		if (mddev->ro &&
-		    rdev->saved_raid_disk < 0)
+		    ! (rdev->saved_raid_disk >= 0 &&
+		       !test_bit(Bitmap_sync, &rdev->flags)))
 			continue;
 
 		rdev->recovery_offset = 0;
@@ -7787,9 +7796,12 @@ void md_check_recovery(struct mddev *mddev)
 			 * As we only add devices that are already in-sync,
 			 * we can activate the spares immediately.
 			 */
-			clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
 			remove_and_add_spares(mddev, NULL);
-			mddev->pers->spare_active(mddev);
+			/* There is no thread, but we need to call
+			 * ->spare_active and clear saved_raid_disk
+			 */
+			md_reap_sync_thread(mddev);
+			clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
 			goto unlock;
 		}