Btrfs: fix joining the same transaction handler more than 2 times
If we flush inodes with pending delalloc in a transaction, we may join
the same transaction handler more than 2 times.
The reason is:
Task use_count of trans handle
commit_transaction 1
|-> btrfs_start_delalloc_inodes 1
|-> run_delalloc_nocow 1
|-> join_transaction 2
|-> cow_file_range 2
|-> join_transaction 3
In fact, cow_file_range needn't join the transaction again because the caller
have joined the transaction, so we fix this problem by this way.
Reported-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 259f74e..44a5d73 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -312,6 +312,7 @@
WARN_ON(type != TRANS_JOIN && type != TRANS_JOIN_NOLOCK);
h = current->journal_info;
h->use_count++;
+ WARN_ON(h->use_count > 2);
h->orig_rsv = h->block_rsv;
h->block_rsv = NULL;
goto got_it;