Blame SOURCES/0006-imsm-update-metadata-correctly-while-raid10-double-d.patch

c025cf
From d7a1fda2769ba272d89de6caeab35d52b73a9c3c Mon Sep 17 00:00:00 2001
c025cf
From: Mariusz Tkaczyk <mariusz.tkaczyk@intel.com>
c025cf
Date: Wed, 17 Oct 2018 12:11:41 +0200
c025cf
Subject: [RHEL7.7 PATCH 06/21] imsm: update metadata correctly while raid10
c025cf
 double degradation
c025cf
c025cf
Mdmon calls end_migration() when map state changes from normal to
c025cf
degraded. It is not valid because in raid 10 double degradation case
c025cf
mdmon breaks checkpointing but array is still rebuilding.
c025cf
In this case mdmon has to mark map as degraded and continues marking
c025cf
recovery checkpoint in metadata. Migration can be finished only if newly
c025cf
failed device is a rebuilding device.
c025cf
c025cf
Add catching double degraded to degraded transition. Migration is
c025cf
finished but map state doesn't change, array is still degraded.
c025cf
c025cf
Update failed_disk_num correctly. If double degradation
c025cf
happens rebuild will start on the lowest slot, but this variable points
c025cf
to the first failed slot. If second fail happens while rebuild this
c025cf
variable shouldn't be updated until rebuild is not finished.
c025cf
c025cf
Signed-off-by: Mariusz Tkaczyk <mariusz.tkaczyk@intel.com>
c025cf
Signed-off-by: Jes Sorensen <jsorensen@fb.com>
c025cf
---
c025cf
 super-intel.c | 25 +++++++++++++++++++------
c025cf
 1 file changed, 19 insertions(+), 6 deletions(-)
c025cf
c025cf
diff --git a/super-intel.c b/super-intel.c
c025cf
index 6438987..d2035cc 100644
c025cf
--- a/super-intel.c
c025cf
+++ b/super-intel.c
c025cf
@@ -8136,7 +8136,8 @@ static int mark_failure(struct intel_super *super,
c025cf
 			set_imsm_ord_tbl_ent(map2, slot2,
c025cf
 					     idx | IMSM_ORD_REBUILD);
c025cf
 	}
c025cf
-	if (map->failed_disk_num == 0xff)
c025cf
+	if (map->failed_disk_num == 0xff ||
c025cf
+		(!is_rebuilding(dev) && map->failed_disk_num > slot))
c025cf
 		map->failed_disk_num = slot;
c025cf
 
c025cf
 	clear_disk_badblocks(super->bbm_log, ord_to_idx(ord));
c025cf
@@ -8558,13 +8559,25 @@ static void imsm_set_disk(struct active_array *a, int n, int state)
c025cf
 			break;
c025cf
 		}
c025cf
 		if (is_rebuilding(dev)) {
c025cf
-			dprintf_cont("while rebuilding.");
c025cf
+			dprintf_cont("while rebuilding ");
c025cf
 			if (map->map_state != map_state)  {
c025cf
-				dprintf_cont(" Map state change");
c025cf
-				end_migration(dev, super, map_state);
c025cf
+				dprintf_cont("map state change ");
c025cf
+				if (n == map->failed_disk_num) {
c025cf
+					dprintf_cont("end migration");
c025cf
+					end_migration(dev, super, map_state);
c025cf
+				} else {
c025cf
+					dprintf_cont("raid10 double degradation, map state change");
c025cf
+					map->map_state = map_state;
c025cf
+				}
c025cf
 				super->updates_pending++;
c025cf
-			} else if (!rebuild_done) {
c025cf
+			} else if (!rebuild_done)
c025cf
 				break;
c025cf
+			else if (n == map->failed_disk_num) {
c025cf
+				/* r10 double degraded to degraded transition */
c025cf
+				dprintf_cont("raid10 double degradation end migration");
c025cf
+				end_migration(dev, super, map_state);
c025cf
+				a->last_checkpoint = 0;
c025cf
+				super->updates_pending++;
c025cf
 			}
c025cf
 
c025cf
 			/* check if recovery is really finished */
c025cf
@@ -8575,7 +8588,7 @@ static void imsm_set_disk(struct active_array *a, int n, int state)
c025cf
 				}
c025cf
 			if (recovery_not_finished) {
c025cf
 				dprintf_cont("\n");
c025cf
-				dprintf("Rebuild has not finished yet, state not changed");
c025cf
+				dprintf_cont("Rebuild has not finished yet, map state changes only if raid10 double degradation happens");
c025cf
 				if (a->last_checkpoint < mdi->recovery_start) {
c025cf
 					a->last_checkpoint =
c025cf
 						mdi->recovery_start;
c025cf
-- 
c025cf
2.7.5
c025cf