tree 2f292659ac8e6a5c3d8ec55e7bdb9339cc37df0e
parent 21ac19d484a8ffb66f64487846c8d53afef04d2b
author Mi Jinlong <mijinlong@cn.fujitsu.com> 1288405173 +0800
committer Trond Myklebust <Trond.Myklebust@netapp.com> 1291768244 -0500

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>