[PATCH] device-mapper: let freeze_bdev return error

Allow freeze_bdev() to return an error.

Signed-Off-By: Alasdair G Kergon <agk@redhat.com>
From: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 17 insertions, 1 deletions

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 0e4c8d3ca9fb..9687a084b5ff 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -991,22 +991,38 @@ int dm_swap_table(struct mapped_device *md, struct dm_table *table)
  */
 static int __lock_fs(struct mapped_device *md)
 {
+        int error = -ENOMEM;
+
         if (test_and_set_bit(DMF_FS_LOCKED, &md->flags))
                 return 0;
 
         md->frozen_bdev = bdget_disk(md->disk, 0);
         if (!md->frozen_bdev) {
                 DMWARN("bdget failed in __lock_fs");
-                return -ENOMEM;
+                goto out;
         }
 
         WARN_ON(md->frozen_sb);
+
         md->frozen_sb = freeze_bdev(md->frozen_bdev);
+        if (IS_ERR(md->frozen_sb)) {
+                error = PTR_ERR(md->frozen_sb);
+                goto out_bdput;
+        }
+
         /* don't bdput right now, we don't want the bdev
          * to go away while it is locked.  We'll bdput
          * in __unlock_fs
          */
         return 0;
+
+out_bdput:
+        bdput(md->frozen_bdev);
+        md->frozen_sb = NULL;
+        md->frozen_bdev = NULL;
+out:
+        clear_bit(DMF_FS_LOCKED, &md->flags);
+        return error;
 }
 
 static void __unlock_fs(struct mapped_device *md)