[PATCH 3.16.y-ckt 47/71] btrfs: cleanup orphans while looking up default subvolume

[Luis Henriques]

3.16.7-ckt14 -stable review patch.  If anyone has any objections, please let me know.

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

From: Jeff Mahoney <jeffm at suse.com>

commit 727b9784b6085c99c2f836bf4fcc2848dc9cf904 upstream.

Orphans in the fs tree are cleaned up via open_ctree and subvolume
orphans are cleaned via btrfs_lookup_dentry -- except when a default
subvolume is in use.  The name for the default subvolume uses a manual
lookup that doesn't trigger orphan cleanup and needs to trigger it
manually as well. This doesn't apply to the remount case since the
subvolumes are cleaned up by walking the root radix tree.

Signed-off-by: Jeff Mahoney <jeffm at suse.com>
Reviewed-by: David Sterba <dsterba at suse.cz>
Signed-off-by: Chris Mason <clm at fb.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 fs/btrfs/super.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 8e16bca69c56..600035120ca3 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -902,6 +902,15 @@ find_root:
 	if (IS_ERR(new_root))
 		return ERR_CAST(new_root);
 
+	if (!(sb->s_flags & MS_RDONLY)) {
+		int ret;
+		down_read(&fs_info->cleanup_work_sem);
+		ret = btrfs_orphan_cleanup(new_root);
+		up_read(&fs_info->cleanup_work_sem);
+		if (ret)
+			return ERR_PTR(ret);
+	}
+
 	dir_id = btrfs_root_dirid(&new_root->root_item);
 setup_root:
 	location.objectid = dir_id;