[PATCH 4.18 114/168] dm raid: fix rebuild of specific devices by updating superblock

[Greg Kroah-Hartman]

4.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Heinz Mauelshagen <heinzm@xxxxxxxxxx>

[ Upstream commit c44a5ee803d2b7ed8c2e6ce24a5c4dd60778886e ]

Update superblock when particular devices are requested via rebuild
(e.g. lvconvert --replace ...) to avoid spurious failure with the "New
device injected into existing raid set without 'delta_disks' or
'rebuild' parameter specified" error message.

Signed-off-by: Heinz Mauelshagen <heinzm@xxxxxxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/md/dm-raid.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -3126,6 +3126,11 @@ static int raid_ctr(struct dm_target *ti
 		set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
 		rs_set_new(rs);
 	} else if (rs_is_recovering(rs)) {
+		/* Rebuild particular devices */
+		if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags)) {
+			set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
+			rs_setup_recovery(rs, MaxSector);
+		}
 		/* A recovering raid set may be resized */
 		; /* skip setup rs */
 	} else if (rs_is_reshaping(rs)) {