Btrfs: check the root passed to btrfs_end_transaction

This patch only add a consistancy check to validate that the
same root is passed to start_transaction and end_transaction.
Subvolume quota depends on this.

Signed-off-by: Arne Jansen <sensille@gmx.net>

1 files changed, 6 insertions, 0 deletions

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 621c8dc48fb6..23cbda0685b8 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -345,6 +345,7 @@ again:
         h->transaction = cur_trans;
         h->blocks_used = 0;
         h->bytes_reserved = 0;
+        h->root = root;
         h->delayed_ref_updates = 0;
         h->use_count = 1;
         h->block_rsv = NULL;
@@ -511,6 +512,11 @@ 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);
         while (count < 2) {
                 unsigned long cur = trans->delayed_ref_updates;
                 trans->delayed_ref_updates = 0;