[PATCH] btrfs: User assert to document transaction requirement

[Nikolay Borisov]

Using an ASSERT in btrfs_pin_extent allows to more stringently observe
whether the function is called under a transaction or not.

Signed-off-by: Nikolay Borisov <nbori...@suse.com>
---
 fs/btrfs/extent-tree.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 5f4b0c4e22aa..59989ee64dbc 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -2589,15 +2589,14 @@ static int pin_down_extent(struct 
btrfs_block_group_cache *cache,
                         bytenr + num_bytes - 1, GFP_NOFS | __GFP_NOFAIL);
 }
 
-/*
- * this function must be called within transaction
- */
 int btrfs_pin_extent(struct btrfs_fs_info *fs_info,
                     u64 bytenr, u64 num_bytes, int reserved)
 {
        struct btrfs_block_group_cache *cache;
        int ret;
 
+       ASSERT(fs_info->running_transaction);
+
        cache = btrfs_lookup_block_group(fs_info, bytenr);
        BUG_ON(!cache); /* Logic error */
 
-- 
2.17.1