[V2] Btrfs: fix warning when creating snapshots

Commit Message

Liu Bo March 13, 2013, 1:43 p.m. UTC

Creating snapshot passes extent_root to commit its transaction,
but it can lead to the warning of checking root for quota in
the __btrfs_end_transaction() when someone else is committing
the current transaction.  Since we've recorded the needed root
in trans_handle, just use it to get rid of the warning.

Signed-off-by: Liu Bo <[e-mail]>
---
v2: fix stupid finger error, I didn't remove the WARN_ON line.

Josef,

Could you please replace the one in btrfs-next with this one?  Thanks,

 fs/btrfs/transaction.c |   11 +++++------
 1 files changed, 5 insertions(+), 6 deletions(-)

Patch

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index fedede1..c4a1531 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -626,14 +626,13 @@  static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
 
 	btrfs_trans_release_metadata(trans, root);
 	trans->block_rsv = NULL;
-	/*
-	 * the same root has to be passed to start_transaction and
-	 * end_transaction. Subvolume quota depends on this.
-	 */
-	WARN_ON(trans->root != root);
 
 	if (trans->qgroup_reserved) {
-		btrfs_qgroup_free(root, trans->qgroup_reserved);
+		/*
+		 * the same root has to be passed here between start_transaction
+		 * and end_transaction. Subvolume quota depends on this.
+		 */
+		btrfs_qgroup_free(trans->root, trans->qgroup_reserved);
 		trans->qgroup_reserved = 0;
 	}