On Fri, 2018-10-19 at 14:20 +0200, Miklos Szeredi wrote:
> As per statx(2) man page only clear out flags that are unsupported by
> the
> fs or have an unrepresentable value. Atime is supported by NFS as
> long as
> it's supported on the server.
>
> So the STATX_ATIME flag should not be cleared in the result_mask if
> the
> operation was requested on a MNT_NOATIME or MNT_NODIRATIME mount.
>
> This patch doesn't change the revalidation algorithm in any way, just
> the
> clearing of flags in stat->result_mask.
>
> Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
> Fixes: 9ccee940bd5b ("Support statx() mask and query flags
> parameters")
> Cc: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
> ---
> fs/nfs/inode.c | 5 +----
> 1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
> index b65aee481d13..34bb3e591709 100644
> --- a/fs/nfs/inode.c
> +++ b/fs/nfs/inode.c
> @@ -811,7 +811,7 @@ int nfs_getattr(const struct path *path, struct
> kstat *stat,
> if (!(request_mask &
> (STATX_MODE|STATX_NLINK|STATX_ATIME|STATX_CTIME|
> STATX_MTIME|STATX_UID|STATX_GID
> |
> STATX_SIZE|STATX_BLOCKS)))
> - goto out_no_revalidate;
> + goto out_no_update;
>
> /* Check whether the cached attributes are stale */
> do_update |= force_sync || nfs_attribute_cache_expired(inode);
> @@ -833,9 +833,6 @@ int nfs_getattr(const struct path *path, struct
> kstat *stat,
> goto out;
> } else
> nfs_readdirplus_parent_cache_hit(path->dentry);
> -out_no_revalidate:
> - /* Only return attributes that were revalidated. */
> - stat->result_mask &= request_mask;
> out_no_update:
> generic_fillattr(inode, stat);
> stat->ino = nfs_compat_user_ino64(NFS_FILEID(inode));
NACK.
When we don't revalidate the attribute, then the content of the field
contains junk values. The above code is very intentional.
--
Trond Myklebust
Linux NFS client maintainer, Hammerspace
trond.myklebust@xxxxxxxxxxxxxxx
