[PATCH 5/5] btrfs: Replace BUG_ON with ASSERT in find_lock_delalloc_range

[Nikolay Borisov <nborisov@suse.com>]

lock_delalloc_pages should only return 2 values - 0 in case of success
and -EAGAIN if the range of pages to be locked should be shrunk due to
some of gone. Manual inspections confirms that this is
indeed the case since __process_pages_contig is where lock_delalloc_pages
gets its return value. The latter always returns 0  or -EAGAIN so the
invariant holds. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
---
 fs/btrfs/extent_io.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 1a9a521aefe5..94bc53472031 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -1606,6 +1606,7 @@ static noinline_for_stack u64 find_lock_delalloc_range(struct inode *inode,
 	/* step two, lock all the pages after the page that has start */
 	ret = lock_delalloc_pages(inode, locked_page,
 				  delalloc_start, delalloc_end);
+	ASSERT(!ret || ret == -EAGAIN);
 	if (ret == -EAGAIN) {
 		/* some of the pages are gone, lets avoid looping by
 		 * shortening the size of the delalloc range we're searching
@@ -1621,7 +1622,6 @@ static noinline_for_stack u64 find_lock_delalloc_range(struct inode *inode,
 			goto out_failed;
 		}
 	}
-	BUG_ON(ret); /* Only valid values are 0 and -EAGAIN */
 
 	/* step three, lock the state bits for the whole range */
 	lock_extent_bits(tree, delalloc_start, delalloc_end, &cached_state);
-- 
2.7.4