From 8f172904b45a6b530eaa345b23956682629bddee Mon Sep 17 00:00:00 2001

From: Josef Bacik <josef@redhat.com>

Date: Fri, 22 Oct 2010 15:26:53 -0400

Subject: Btrfs: fix error handling in btrfs_get_sb

If we failed to find the root subvol id, or the subvol=<name>, we would

deactivate the locked super and close the devices.  The problem is at this point

we have gotten the SB all setup, which includes setting super_operations, so

when we'd deactiveate the super, we'd do a close_ctree() which closes the

devices, so we'd end up closing the devices twice.  So if you do something like

this

mount /dev/sda1 /mnt/test1

mount /dev/sda1 /mnt/test2 -o subvol=xxx

umount /mnt/test1

it would blow up (if subvol xxx doesn't exist).  This patch fixes that problem.

Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>

---

 fs/btrfs/super.c |    7 +++----

 1 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c

index f2393b3..c246f25 100644

--- a/fs/btrfs/super.c

+++ b/fs/btrfs/super.c

@@ -629,7 +629,7 @@ static int btrfs_get_sb(struct file_system_type *fs_type, int flags,

 	if (IS_ERR(root)) {

 		error = PTR_ERR(root);

 		deactivate_locked_super(s);

-		goto error;

+		goto error_free_subvol_name;

 	}

 	/* if they gave us a subvolume name bind mount into that */

 	if (strcmp(subvol_name, ".")) {

@@ -643,14 +643,14 @@ static int btrfs_get_sb(struct file_system_type *fs_type, int flags,

 			deactivate_locked_super(s);

 			error = PTR_ERR(new_root);

 			dput(root);

-			goto error_close_devices;

+			goto error_free_subvol_name;

 		}

 		if (!new_root->d_inode) {

 			dput(root);

 			dput(new_root);

 			deactivate_locked_super(s);

 			error = -ENXIO;

-			goto error_close_devices;

+			goto error_free_subvol_name;

 		}

 		dput(root);

 		root = new_root;

@@ -668,7 +668,6 @@ error_close_devices:

 	btrfs_close_devices(fs_devices);

 error_free_subvol_name:

 	kfree(subvol_name);

-error:

 	return error;

 }

-- 

1.7.3.3