Re: [PATCH 03/10] nfs41: fix cb_recall bug

[Trond Myklebust <trond.myklebust@fys.uio.no>]

On Mon, 2009-11-23 at 13:54 -0800, Alexandros Batsakis wrote: 
> in NFSv4.1 the seqid part of a stateid in CB_RECALL must be 0
> 
> Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
> ---
>  fs/nfs/delegation.c |   21 +++++++++++++++++----
>  1 files changed, 17 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c
> index 6dd48a4..4096dcf 100644
> --- a/fs/nfs/delegation.c
> +++ b/fs/nfs/delegation.c
> @@ -432,18 +432,31 @@ int nfs_async_inode_return_delegation(struct inode *inode, const nfs4_stateid *s
>  {
>  	struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
>  	struct nfs_delegation *delegation;
> +	u32 seqid_len = 0;
>  
>  	rcu_read_lock();
>  	delegation = rcu_dereference(NFS_I(inode)->delegation);
> -	if (delegation == NULL || memcmp(delegation->stateid.data, stateid->data,
> -				sizeof(delegation->stateid.data)) != 0) {
> -		rcu_read_unlock();
> -		return -ENOENT;
> +	if (delegation == NULL)
> +		goto enoent;
> +
> +	if (clp->cl_minorversion > 0) {
> +		if (((u32 *) &stateid->data)[0] != 0)
> +			goto enoent;
> +		seqid_len = 4;
>  	}
> +
> +	if (memcmp(&delegation->stateid.data[seqid_len],
> +		   &stateid->data[seqid_len],
> +		   sizeof(stateid->data)-seqid_len))
> +		goto enoent;

cl_minorversion has nothing to do with generic delegation code. Please
just let the comparison be a pointer-to-function argument to
nfs_async_inode_return_delegation.

> +
>  	nfs_mark_return_delegation(clp, delegation);
>  	rcu_read_unlock();
>  	nfs_delegation_run_state_manager(clp);
>  	return 0;
> +enoent:
> +	rcu_read_unlock();
> +	return -ENOENT;
>  }
>  
>  /*