Btrfs: remove BUG_ON() due to mounting bad filesystem

Mounting a bad filesystem caused a BUG_ON(). The following is steps to
reproduce it.
 # mkfs.btrfs /dev/sda2
 # mount /dev/sda2 /mnt
 # mkfs.btrfs /dev/sda1 /dev/sda2
 (the program says that /dev/sda2 was mounted, and then exits. )
 # umount /mnt
 # mount /dev/sda1 /mnt

At the third step, mkfs.btrfs exited in the way of make filesystem. So the
initialization of the filesystem didn't finish. So the filesystem was bad, and
it caused BUG_ON() when mounting it. But BUG_ON() should be called by the wrong
code, not user's operation, so I think it is a bug of btrfs.

This patch fixes it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 87b2554..2b59201 100644 (file)
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1982,7 +1982,12 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 
        if (!(sb->s_flags & MS_RDONLY)) {
                ret = btrfs_recover_relocation(tree_root);
-               BUG_ON(ret);
+               if (ret < 0) {
+                       printk(KERN_WARNING
+                              "btrfs: failed to recover relocation\n");
+                       err = -EINVAL;
+                       goto fail_trans_kthread;
+               }
        }
 
        location.objectid = BTRFS_FS_TREE_OBJECTID;

diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index ed3e4a2..ab7ab53 100644 (file)
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -3764,7 +3764,8 @@ out:
                                       BTRFS_DATA_RELOC_TREE_OBJECTID);
                if (IS_ERR(fs_root))
                        err = PTR_ERR(fs_root);
-               btrfs_orphan_cleanup(fs_root);
+               else
+                       btrfs_orphan_cleanup(fs_root);
        }
        return err;
 }