[pnfs] [PATCH 4/5] Shut down the v4 style callback server for v4.1

[Benny Halevy]

iyer at netapp.com wrote:
> From: Rahul Iyer <iyer at netapp.com>
> 
> This patch shuts down the v4.1 server in case the mount is a v4.1 mount. If
> it's a v4 mount, nothing changes.
> 
> Signed-off-by: Rahul Iyer <iyer at netapp.com>
> ---
>  fs/nfs/super.c |   11 ++++++++++-
>  1 files changed, 10 insertions(+), 1 deletions(-)
> 
> diff --git a/fs/nfs/super.c b/fs/nfs/super.c
> index 89eb564..3411ea1 100644
> --- a/fs/nfs/super.c
> +++ b/fs/nfs/super.c
> @@ -1270,8 +1270,17 @@ static int nfs4_fill_super(struct super_block *sb, struct nfs4_mount_data *data,
>                                  printk(KERN_EMERG "Couldn't mount using minorversion %d\n", i);
>                                  rpc_shutdown_client(server->client);
>                          }
> -			else
> +			else {
> +				/* We successfully managed to set up a session.
> +				 * Since the v4.1 callbacks are different from
> +				 * that of v4, shutdown the v4 callback server
> +				 * started up in nfs4_alloc_client
> +				 */
> +				if (i > 0)
> +					nfs_callback_down();

I really don't like this, and the comment that's needed to explain it.
Rather than tearing down the nfs callback path, it shouldn't have been established
for i > 0 in the first place.
A flag asking to create a callback path should be passed down to
nfs4_{create,get,alloc}_client.

> +				
>  				break;
> +			}
>                  }
>          }
>