f2fs: fix handling errors got by f2fs_write_inode

Ruslan reported that f2fs hangs with an infinite loop in f2fs_sync_file():

	while (sync_node_pages(sbi, inode->i_ino, &wbc) == 0)
		f2fs_write_inode(inode, NULL);

The reason was revealed that the cold flag is not set even thought this inode is
a normal file. Therefore, sync_node_pages() skips to write node blocks since it
only writes cold node blocks.

The cold flag is stored to the node_footer in node block, and whenever a new
node page is allocated, it is set according to its file type, file or directory.

But, after sudden-power-off, when recovering the inode page, f2fs doesn't recover
its cold flag.

So, let's assign the cold flag in more right places.

One more thing:
If f2fs_write_inode() returns an error due to whatever situations, there would
be no dirty node pages so that sync_node_pages() returns zero.
(i.e., zero means nothing was written.)

Reported-by: Ruslan N. Marchenko <me@ruff.mobi>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
index df5fb381ebf..bf20b4d0321 100644
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -203,6 +203,7 @@ void update_inode(struct inode *inode, struct page *node_page)
 	ri->i_flags = cpu_to_le32(F2FS_I(inode)->i_flags);
 	ri->i_pino = cpu_to_le32(F2FS_I(inode)->i_pino);
 	ri->i_generation = cpu_to_le32(inode->i_generation);
+	set_cold_node(inode, node_page);
 	set_page_dirty(node_page);
 }