Re: [PATCH v2 3/7] nfsd: use ATTR_CTIME_SET for delegated ctime updates

Chuck Lever
2025-07-26T18:49:15Z

Hi Jeff -

Thanks again for your focus on getting this straightened out!

On 7/26/25 10:31 AM, Jeff Layton wrote:
> Ensure that notify_change() doesn't clobber a delegated ctime update
> with current_time() by setting ATTR_CTIME_SET for those updates.
>
> Also, set the tv_nsec field the nfsd4_decode_fattr4 to the correct
> value.

I don't yet see the connection of the above tv_nsec fix to the other
changes in this patch. Wouldn't this be an independent fix?

> Don't bother setting the timestamps in cb_getattr_update_times() in the
> non-delegated case. notify_change() will do that itself.
>
> Signed-off-by: Jeff Layton <jlayton@kernel.org>

General comments:

I don't feel that any of the patches in this series need to be tagged
for stable, since there is already a Kconfig setting that defaults to
leaving timestamp delegation disabled. But I would like to see Fixes:
tags, where that makes sense?

Is this set on top of the set you posted a day or two ago with the new
trace point? Or does this set replace that one?

> ---
> fs/nfsd/nfs4state.c | 6 +++---
> fs/nfsd/nfs4xdr.c | 5 +++--
> 2 files changed, 6 insertions(+), 5 deletions(-)
>
> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> index 88c347957da5b8f352be63f84f207d2225f81cb9..77eea2ad93cc07939f045fc4b983b1ac00d068b8 100644
> --- a/fs/nfsd/nfs4state.c
> +++ b/fs/nfsd/nfs4state.c
> @@ -9167,7 +9167,6 @@ static bool set_cb_time(struct timespec64 *cb, const struct timespec64 *orig,
> static int cb_getattr_update_times(struct dentry *dentry, struct nfs4_delegation *dp)
> {
> struct inode *inode = d_inode(dentry);
> - struct timespec64 now = current_time(inode);
> struct nfs4_cb_fattr *ncf = &dp->dl_cb_fattr;
> struct iattr attrs = { };
> int ret;
> @@ -9175,6 +9174,7 @@ static int cb_getattr_update_times(struct dentry *dentry, struct nfs4_delegation
> if (deleg_attrs_deleg(dp->dl_type)) {
> struct timespec64 atime = inode_get_atime(inode);
> struct timespec64 mtime = inode_get_mtime(inode);
> + struct timespec64 now = current_time(inode);
>
> attrs.ia_atime = ncf->ncf_cb_atime;
> attrs.ia_mtime = ncf->ncf_cb_mtime;
> @@ -9183,12 +9183,12 @@ static int cb_getattr_update_times(struct dentry *dentry, struct nfs4_delegation
> attrs.ia_valid |= ATTR_ATIME | ATTR_ATIME_SET;
>
> if (set_cb_time(&attrs.ia_mtime, &mtime, &now)) {
> - attrs.ia_valid |= ATTR_CTIME | ATTR_MTIME | ATTR_MTIME_SET;
> + attrs.ia_valid |= ATTR_CTIME | ATTR_CTIME_SET |
> + ATTR_MTIME | ATTR_MTIME_SET;
> attrs.ia_ctime = attrs.ia_mtime;
> }
> } else {
> attrs.ia_valid |= ATTR_MTIME | ATTR_CTIME;
> - attrs.ia_mtime = attrs.ia_ctime = now;
> }
>
> if (!attrs.ia_valid)
> diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
> index 8b68f74a8cf08c6aa1305a2a3093467656085e4a..c0a3c6a7c8bb70d62940115c3101e9f897401456 100644
> --- a/fs/nfsd/nfs4xdr.c
> +++ b/fs/nfsd/nfs4xdr.c
> @@ -538,8 +538,9 @@ nfsd4_decode_fattr4(struct nfsd4_compoundargs *argp, u32 *bmval, u32 bmlen,
> iattr->ia_mtime.tv_sec = modify.seconds;
> iattr->ia_mtime.tv_nsec = modify.nseconds;
> iattr->ia_ctime.tv_sec = modify.seconds;
> - iattr->ia_ctime.tv_nsec = modify.seconds;
> - iattr->ia_valid |= ATTR_CTIME | ATTR_MTIME | ATTR_MTIME_SET | ATTR_DELEG;
> + iattr->ia_ctime.tv_nsec = modify.nseconds;
> + iattr->ia_valid |= ATTR_CTIME | ATTR_CTIME_SET |
> + ATTR_MTIME | ATTR_MTIME_SET | ATTR_DELEG;
> }
>
> /* request sanity: did attrlist4 contain the expected number of words? */
>

--
Chuck Lever