[PATCH] f2fs: fix to unlock node page when it was truncated

[Jaegeuk Kim <jaegeuk.kim@samsung.com>]

If the node page was truncated, its block address became zero.
This means that we don't need to write the node page, but have to unlock
NODE_WRITE, decrease the number of dirty node pages, and then unlock_page
before returning the f2fs_write_node_page with zero.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
---
 fs/f2fs/node.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index e275218..3dc63f4 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1106,15 +1106,15 @@ static int f2fs_write_node_page(struct page *page,
 
 	/* This page is already truncated */
 	if (ni.blk_addr == NULL_ADDR)
-		return 0;
+		goto out;
 
 	set_page_writeback(page);
 
 	/* insert node offset */
 	write_node_page(sbi, page, nid, ni.blk_addr, &new_addr);
 	set_node_addr(sbi, &ni, new_addr);
+out:
 	dec_page_count(sbi, F2FS_DIRTY_NODES);
-
 	mutex_unlock_op(sbi, NODE_WRITE);
 	unlock_page(page);
 	return 0;
-- 
1.8.1.3.566.gaa39828