[PATCH v2] btrfs: handle failures of set_extent_bits in add_excluded_extent

[Gu Jinxiang <gujx@cn.fujitsu.com>]

set_extent_bits may fail, return the result in add_excluded_extent.

Signed-off-by: Gu Jinxiang <gujx@cn.fujitsu.com>
Changelog:
v2-v1:
 1.remove goto to make the function run linearly.
 2.change commit description not pointing out the failure detail,
   since set_extent_bits's failure type may be added.
---
 fs/btrfs/extent-tree.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 75cfb80d2551..65ef3456fa62 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -215,11 +215,15 @@ static int add_excluded_extent(struct btrfs_fs_info *fs_info,
 			       u64 start, u64 num_bytes)
 {
 	u64 end = start + num_bytes - 1;
-	set_extent_bits(&fs_info->freed_extents[0],
+	int ret = 0;
+
+	ret = set_extent_bits(&fs_info->freed_extents[0],
 			start, end, EXTENT_UPTODATE);
-	set_extent_bits(&fs_info->freed_extents[1],
+	if (ret)
+		return ret;
+	ret = set_extent_bits(&fs_info->freed_extents[1],
 			start, end, EXTENT_UPTODATE);
-	return 0;
+	return ret;
 }
 
 static void free_excluded_extents(struct btrfs_fs_info *fs_info,
-- 
1.9.1