Re: [PATCH v2] f2fs: remain written times to update inode during fsync

[Jaegeuk Kim <jaegeuk@kernel.org>]

Change log from v1:
 - add more description

This fixes xfstests/generic/392.

The failure was caused by different times between 1) one marked in the last
fsync(2) call and 2) the other given by roll-forward recovery after power-cut.
The reason was that we skipped updating inode block at 1), since its i_size
was recoverable along with 4KB-aligned data writes, which was fixed by:
  "f2fs: fix a wrong condition in f2fs_skip_inode_update"

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
---
 fs/f2fs/f2fs.h  | 15 +++++++++++++++
 fs/f2fs/inode.c |  4 ++++
 2 files changed, 19 insertions(+)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 000f93f6767e..675c39d85111 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -664,6 +664,7 @@ struct f2fs_inode_info {
 	kprojid_t i_projid;		/* id for project quota */
 	int i_inline_xattr_size;	/* inline xattr size */
 	struct timespec i_crtime;	/* inode creation time */
+	struct timespec i_disk_time[4];	/* inode disk times */
 };
 
 static inline void get_extent_info(struct extent_info *ext,
@@ -2457,6 +2458,11 @@ static inline void clear_file(struct inode *inode, int type)
 	f2fs_mark_inode_dirty_sync(inode, true);
 }
 
+static inline bool time_equal(struct timespec a, struct timespec b)
+{
+	return (a.tv_sec == b.tv_sec) && (a.tv_nsec == b.tv_nsec);
+}
+
 static inline bool f2fs_skip_inode_update(struct inode *inode, int dsync)
 {
 	bool ret;
@@ -2474,6 +2480,15 @@ static inline bool f2fs_skip_inode_update(struct inode *inode, int dsync)
 			i_size_read(inode) & ~PAGE_MASK)
 		return false;
 
+	if (!time_equal(F2FS_I(inode)->i_disk_time[0], inode->i_atime))
+		return false;
+	if (!time_equal(F2FS_I(inode)->i_disk_time[1], inode->i_ctime))
+		return false;
+	if (!time_equal(F2FS_I(inode)->i_disk_time[2], inode->i_mtime))
+		return false;
+	if (!time_equal(F2FS_I(inode)->i_disk_time[3], F2FS_I(inode)->i_crtime))
+		return false;
+
 	down_read(&F2FS_I(inode)->i_sem);
 	ret = F2FS_I(inode)->last_disk_size == i_size_read(inode);
 	up_read(&F2FS_I(inode)->i_sem);
diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
index 401f09ccce7e..70aba580f4b0 100644
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -444,6 +444,10 @@ void update_inode(struct inode *inode, struct page *node_page)
 	if (inode->i_nlink == 0)
 		clear_inline_node(node_page);
 
+	F2FS_I(inode)->i_disk_time[0] = inode->i_atime;
+	F2FS_I(inode)->i_disk_time[1] = inode->i_ctime;
+	F2FS_I(inode)->i_disk_time[2] = inode->i_mtime;
+	F2FS_I(inode)->i_disk_time[3] = F2FS_I(inode)->i_crtime;
 }
 
 void update_inode_page(struct inode *inode)
-- 
2.15.0.531.g2ccb3012c9-goog