[RFC PATCH 3/3][RESEND] xfs: mark the inode for high-res timestamp update in getattr

Jeff Layton
2023-04-11T14:37:31Z

When the mtime or ctime is being queried via getattr, ensure that we
mark the inode for a high-res timestamp update on the next pass. Also,
switch to current_cmtime for other c/mtime updates.

With this change, we're better off having the NFS server just ignore
the i_version field and have it use the ctime instead, so clear the
STATX_CHANGE_COOKIE flag in the result mask in ->getattr.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
fs/xfs/libxfs/xfs_trans_inode.c | 2 +-
fs/xfs/xfs_acl.c | 2 +-
fs/xfs/xfs_inode.c | 2 +-
fs/xfs/xfs_iops.c | 15 ++++++++++++---
4 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_trans_inode.c b/fs/xfs/libxfs/xfs_trans_inode.c
index 8b5547073379..9ad7c229c617 100644
--- a/fs/xfs/libxfs/xfs_trans_inode.c
+++ b/fs/xfs/libxfs/xfs_trans_inode.c
@@ -63,7 +63,7 @@ xfs_trans_ichgtime(
ASSERT(tp);
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));

- tv = current_time(inode);
+ tv = current_cmtime(inode);

if (flags & XFS_ICHGTIME_MOD)
inode->i_mtime = tv;
diff --git a/fs/xfs/xfs_acl.c b/fs/xfs/xfs_acl.c
index 791db7d9c849..461adc58cf8c 100644
--- a/fs/xfs/xfs_acl.c
+++ b/fs/xfs/xfs_acl.c
@@ -233,7 +233,7 @@ xfs_acl_set_mode(
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
inode->i_mode = mode;
- inode->i_ctime = current_time(inode);
+ inode->i_ctime = current_cmtime(inode);
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);

if (xfs_has_wsync(mp))
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 5808abab786c..80f9d731e261 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -843,7 +843,7 @@ xfs_init_new_inode(
ip->i_df.if_nextents = 0;
ASSERT(ip->i_nblocks == 0);

- tv = current_time(inode);
+ tv = current_cmtime(inode);
inode->i_mtime = tv;
inode->i_atime = tv;
inode->i_ctime = tv;
diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index 24718adb3c16..a0b07f90e16c 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -565,6 +565,15 @@ xfs_vn_getattr(
if (xfs_is_shutdown(mp))
return -EIO;

+ /*
+ * XFS uses the i_version infrastructure to track any change to
+ * the inode, including atime updates. This means that the i_version
+ * returned by getattr doesn't conform to what the callers expect.
+ * Clear it here so that nfsd will fake up a change cookie from the
+ * ctime instead.
+ */
+ stat->result_mask &= ~STATX_CHANGE_COOKIE;
+
stat->size = XFS_ISIZE(ip);
stat->dev = inode->i_sb->s_dev;
stat->mode = inode->i_mode;
@@ -573,8 +582,8 @@ xfs_vn_getattr(
stat->gid = vfsgid_into_kgid(vfsgid);
stat->ino = ip->i_ino;
stat->atime = inode->i_atime;
- stat->mtime = inode->i_mtime;
- stat->ctime = inode->i_ctime;
+ if (request_mask & (STATX_CTIME|STATX_MTIME))
+ fill_cmtime_and_mark(inode, stat);
stat->blocks = XFS_FSB_TO_BB(mp, ip->i_nblocks + ip->i_delayed_blks);

if (xfs_has_v3inodes(mp)) {
@@ -917,7 +926,7 @@ xfs_setattr_size(
if (newsize != oldsize &&
!(iattr->ia_valid & (ATTR_CTIME | ATTR_MTIME))) {
iattr->ia_ctime = iattr->ia_mtime =
- current_time(inode);
+ current_cmtime(inode);
iattr->ia_valid |= ATTR_CTIME | ATTR_MTIME;
}

--
2.39.2