On 3 Aug 2025, at 21:29, Trond Myklebust wrote:
> From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
>
> When crossing into a new filesystem, the NFSv4 client will look up the
> new directory, and then call nfs4_server_capabilities() as well as
> nfs4_do_fsinfo() at least twice.
>
> This patch removes the duplicate calls, and reduces the initial lookup
> to retrieve just a minimal set of attributes.
>
> Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
> ---
> fs/nfs/nfs4_fs.h | 5 ++-
> fs/nfs/nfs4getroot.c | 14 +++----
> fs/nfs/nfs4proc.c | 87 ++++++++++++++++++++------------------------
> 3 files changed, 48 insertions(+), 58 deletions(-)
>
> diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
> index d3ca91f60fc1..c34c89af9c7d 100644
> --- a/fs/nfs/nfs4_fs.h
> +++ b/fs/nfs/nfs4_fs.h
> @@ -63,7 +63,7 @@ struct nfs4_minor_version_ops {
> bool (*match_stateid)(const nfs4_stateid *,
> const nfs4_stateid *);
> int (*find_root_sec)(struct nfs_server *, struct nfs_fh *,
> - struct nfs_fsinfo *);
> + struct nfs_fattr *);
> void (*free_lock_state)(struct nfs_server *,
> struct nfs4_lock_state *);
> int (*test_and_free_expired)(struct nfs_server *,
> @@ -296,7 +296,8 @@ extern int nfs4_call_sync(struct rpc_clnt *, struct nfs_server *,
> extern void nfs4_init_sequence(struct nfs4_sequence_args *, struct nfs4_sequence_res *, int, int);
> extern int nfs4_proc_setclientid(struct nfs_client *, u32, unsigned short, const struct cred *, struct nfs4_setclientid_res *);
> extern int nfs4_proc_setclientid_confirm(struct nfs_client *, struct nfs4_setclientid_res *arg, const struct cred *);
> -extern int nfs4_proc_get_rootfh(struct nfs_server *, struct nfs_fh *, struct nfs_fsinfo *, bool);
> +extern int nfs4_proc_get_rootfh(struct nfs_server *, struct nfs_fh *,
> + struct nfs_fattr *, bool);
> extern int nfs4_proc_bind_conn_to_session(struct nfs_client *, const struct cred *cred);
> extern int nfs4_proc_exchange_id(struct nfs_client *clp, const struct cred *cred);
> extern int nfs4_destroy_clientid(struct nfs_client *clp);
> diff --git a/fs/nfs/nfs4getroot.c b/fs/nfs/nfs4getroot.c
> index 1a69479a3a59..e67ea345de69 100644
> --- a/fs/nfs/nfs4getroot.c
> +++ b/fs/nfs/nfs4getroot.c
> @@ -12,30 +12,28 @@
>
> int nfs4_get_rootfh(struct nfs_server *server, struct nfs_fh *mntfh, bool auth_probe)
> {
> - struct nfs_fsinfo fsinfo;
> + struct nfs_fattr *fattr = nfs_alloc_fattr();
> int ret = -ENOMEM;
>
> - fsinfo.fattr = nfs_alloc_fattr();
> - if (fsinfo.fattr == NULL)
> + if (fattr == NULL)
> goto out;
>
> /* Start by getting the root filehandle from the server */
> - ret = nfs4_proc_get_rootfh(server, mntfh, &fsinfo, auth_probe);
> + ret = nfs4_proc_get_rootfh(server, mntfh, fattr, auth_probe);
> if (ret < 0) {
> dprintk("nfs4_get_rootfh: getroot error = %d\n", -ret);
> goto out;
> }
>
> - if (!(fsinfo.fattr->valid & NFS_ATTR_FATTR_TYPE)
> - || !S_ISDIR(fsinfo.fattr->mode)) {
> + if (!(fattr->valid & NFS_ATTR_FATTR_TYPE) || !S_ISDIR(fattr->mode)) {
> printk(KERN_ERR "nfs4_get_rootfh:"
> " getroot encountered non-directory\n");
> ret = -ENOTDIR;
> goto out;
> }
>
> - memcpy(&server->fsid, &fsinfo.fattr->fsid, sizeof(server->fsid));
> + memcpy(&server->fsid, &fattr->fsid, sizeof(server->fsid));
> out:
> - nfs_free_fattr(fsinfo.fattr);
> + nfs_free_fattr(fattr);
> return ret;
> }
> diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
> index c7c7ec22f21d..7d2b67e06cc3 100644
> --- a/fs/nfs/nfs4proc.c
> +++ b/fs/nfs/nfs4proc.c
> @@ -4240,15 +4240,18 @@ static int nfs4_discover_trunking(struct nfs_server *server,
> }
>
> static int _nfs4_lookup_root(struct nfs_server *server, struct nfs_fh *fhandle,
> - struct nfs_fsinfo *info)
> + struct nfs_fattr *fattr)
> {
> - u32 bitmask[3];
> + u32 bitmask[3] = {
> + [0] = FATTR4_WORD0_TYPE | FATTR4_WORD0_CHANGE |
> + FATTR4_WORD0_SIZE | FATTR4_WORD0_FSID,
Just a thought when noticing this change --
Don't we want at least FATTR4_WORD0_FILEID and
FATTR4_WORD1_MOUNTED_ON_FILEID as well here?
Reviewed-by: Benjamin Coddington <bcodding@xxxxxxxxxx>
Ben
