[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>

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 0e4c8d3ca9fb269347c80ba8bb6f75e891b528ba..9687a084b5ff653c52a61a879267c46c72cab689 100644 (file)
--- 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)