f2fs: sync dir->i_size with its block allocation

If new dentry block is allocated and its i_size is updated, we should update
its inode block together in order to sync i_size and its block allocation.
Otherwise, we can loose additional dentry block due to the unconsistent i_size.

Errorneous Scenario
-------------------

In the recovery routine,
 - recovery_dentry
 | - __f2fs_add_link
 | | - get_new_data_page
 | | | - i_size_write(new_i_size)
 | | | - mark_inode_dirty_sync(dir)
 | | - update_parent_metadata
 | | | - mark_inode_dirty(dir)
 |
 - write_checkpoint
   - sync_dirty_dir_inodes
     - filemap_flush(dentry_blocks)
       - f2fs_write_data_page
         - skip to write the last dentry block due to index < i_size

In the above flow, new_i_size is not updated to its inode block so that the
last dentry block will be lost accordingly.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

1 files changed, 4 insertions, 5 deletions

diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
index eaea5b50d9c1..69ca049b5168 100644
--- a/fs/f2fs/dir.c
+++ b/fs/f2fs/dir.c
@@ -370,22 +370,20 @@ error:
 static void update_parent_metadata(struct inode *dir, struct inode *inode,
 						unsigned int current_depth)
 {
-	bool need_dir_update = false;
-
 	if (is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE)) {
 		if (S_ISDIR(inode->i_mode)) {
 			inc_nlink(dir);
-			need_dir_update = true;
+			set_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
 		}
 		clear_inode_flag(F2FS_I(inode), FI_NEW_INODE);
 	}
 	dir->i_mtime = dir->i_ctime = CURRENT_TIME;
 	if (F2FS_I(dir)->i_current_depth != current_depth) {
 		F2FS_I(dir)->i_current_depth = current_depth;
-		need_dir_update = true;
+		set_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
 	}
 
-	if (need_dir_update)
+	if (is_inode_flag_set(F2FS_I(dir), FI_UPDATE_DIR))
 		update_inode_page(dir);
 	else
 		mark_inode_dirty(dir);
@@ -502,6 +500,7 @@ add_dentry:
 
 	update_parent_metadata(dir, inode, current_depth);
 fail:
+	clear_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
 	kunmap(dentry_page);
 	f2fs_put_page(dentry_page, 1);
 	return err;