From: Jan Schmidt <list.btrfs@jan-o-sch.net>
Date: Fri, 27 Apr 2012 16:41:45 +0000 (-0400)
Subject: Btrfs: fix repair code for RAID10
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=3e74317ad773ba9df36db1fa32848cba41ac4d1a;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git

Btrfs: fix repair code for RAID10

btrfs_map_block sets mirror_num, so that the repair code knows eventually
which device gave us the read error. For RAID10, mirror_num must be 1 or 2.
Before this fix mirror_num was incorrectly related to our stripe index.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
---

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 3b984173d25b..1411b99555a4 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -3807,10 +3807,11 @@ static int __btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
 		else if (mirror_num)
 			stripe_index += mirror_num - 1;
 		else {
+			int old_stripe_index = stripe_index;
 			stripe_index = find_live_mirror(map, stripe_index,
 					      map->sub_stripes, stripe_index +
 					      current->pid % map->sub_stripes);
-			mirror_num = stripe_index + 1;
+			mirror_num = stripe_index - old_stripe_index + 1;
 		}
 	} else {
 		/*