From 64cdb724ea2f65fb9327d430cab82cd51e751cc9 Mon Sep 17 00:00:00 2001
From: NeilBrown <neilb@suse.de>
Date: Fri, 23 Dec 2011 10:17:57 +1100
Subject: [PATCH] --- yaml --- r: 280525 b: refs/heads/master c:
 7ef449d1ec3668acbba6af6a500d0c84636b436f h: refs/heads/master i:   280523:
 ce2760ff31f607d73072c5d6496dd49348c6b552 v: v3

---
 [refs]                   |  2 +-
 trunk/drivers/md/raid1.c | 17 +++++++++++++++--
 2 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/[refs] b/[refs]
index 0eaf46bd8630..1c4d6e5cfca0 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: c19d57980b38a5bb613a898937a1cf85f422fb9b
+refs/heads/master: 7ef449d1ec3668acbba6af6a500d0c84636b436f
diff --git a/trunk/drivers/md/raid1.c b/trunk/drivers/md/raid1.c
index 6df0c41578af..e3cfca7cde16 100644
--- a/trunk/drivers/md/raid1.c
+++ b/trunk/drivers/md/raid1.c
@@ -1315,8 +1315,9 @@ static int raid1_add_disk(struct mddev *mddev, struct md_rdev *rdev)
 	if (rdev->raid_disk >= 0)
 		first = last = rdev->raid_disk;
 
-	for (mirror = first; mirror <= last; mirror++)
-		if ( !(p=conf->mirrors+mirror)->rdev) {
+	for (mirror = first; mirror <= last; mirror++) {
+		p = conf->mirrors+mirror;
+		if (!p->rdev) {
 
 			disk_stack_limits(mddev->gendisk, rdev->bdev,
 					  rdev->data_offset << 9);
@@ -1343,6 +1344,18 @@ static int raid1_add_disk(struct mddev *mddev, struct md_rdev *rdev)
 			rcu_assign_pointer(p->rdev, rdev);
 			break;
 		}
+		if (test_bit(WantReplacement, &p->rdev->flags) &&
+		    p[conf->raid_disks].rdev == NULL) {
+			/* Add this device as a replacement */
+			clear_bit(In_sync, &rdev->flags);
+			set_bit(Replacement, &rdev->flags);
+			rdev->raid_disk = mirror;
+			err = 0;
+			conf->fullsync = 1;
+			rcu_assign_pointer(p[conf->raid_disks].rdev, rdev);
+			break;
+		}
+	}
 	md_integrity_add_rdev(rdev, mddev);
 	print_conf(conf);
 	return err;