nfs: kernel should return EPROTONOSUPPORT when not support NFSv4
When nfs client(kernel) don't support NFSv4, maybe user build
kernel without NFSv4, there is a problem.
Using command "mount SERVER-IP:/nfsv3 /mnt/" to mount NFSv3
filesystem, mount should should success, but fail and get error:
"mount.nfs: an incorrect mount option was specified"
System call mount "nfs"(not "nfs4") with "vers=4",
if CONFIG_NFS_V4 is not defined, the "vers=4" will be parsed
as invalid argument and kernel return EINVAL to nfs-utils.
About that, we really want get EPROTONOSUPPORT rather than
EINVAL. This path make sure kernel parses argument success,
and return EPROTONOSUPPORT at nfs_validate_mount_data().
Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 3c04504..4100630 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -1069,12 +1069,10 @@
mnt->flags |= NFS_MOUNT_VER3;
mnt->version = 3;
break;
-#ifdef CONFIG_NFS_V4
case Opt_v4:
mnt->flags &= ~NFS_MOUNT_VER3;
mnt->version = 4;
break;
-#endif
case Opt_udp:
mnt->flags &= ~NFS_MOUNT_TCP;
mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
@@ -1286,12 +1284,10 @@
mnt->flags |= NFS_MOUNT_VER3;
mnt->version = 3;
break;
-#ifdef CONFIG_NFS_V4
case NFS4_VERSION:
mnt->flags &= ~NFS_MOUNT_VER3;
mnt->version = 4;
break;
-#endif
default:
goto out_invalid_value;
}