Re: [pnfs] [RFC 13/51] FIXME: nfsd41: introduce current_session

[Benny Halevy <bhalevy@panasas.com>]

On Nov. 10, 2008, 22:45 +0200, Benny Halevy <bhalevy@panasas.com> wrote:
> From: Marc Eshel <eshel@almaden.ibm.com>
> 
> FIXME: use a mem pool for current session allocation.
> 

review 11-12: this code is replaced by the DRC patches.
move the latter forward in the patchset.

> The current session is allocated and freed for every compound rpc.
> It holds the session id and slot used by this compound.
> 
> Signed-off-by: Benny Halevy <bhalevy@panasas.com>
> ---
>  fs/nfsd/nfs4proc.c         |   26 ++++++++++++++++++++++++--
>  include/linux/nfsd/state.h |   12 ++++++++++++
>  include/linux/nfsd/xdr4.h  |    3 +++
>  3 files changed, 39 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
> index 9fa60a3..bfebeaa 100644
> --- a/fs/nfsd/nfs4proc.c
> +++ b/fs/nfsd/nfs4proc.c
> @@ -861,11 +861,14 @@ nfsd4_proc_compound(struct svc_rqst *rqstp,
>  		    struct nfsd4_compoundargs *args,
>  		    struct nfsd4_compoundres *resp)
>  {
> -	struct nfsd4_op	*op;
> +	struct nfsd4_op	*op = NULL;
>  	struct nfsd4_operation *opdesc;
>  	struct nfsd4_compound_state *cstate = NULL;
>  	int		slack_bytes;
>  	__be32		status;
> +#if defined(CONFIG_NFSD_V4_1)
> +	struct current_session *current_ses = NULL;
> +#endif /* CONFIG_NFSD_V4_1 */
>  
>  	resp->xbuf = &rqstp->rq_res;
>  	resp->p = rqstp->rq_res.head[0].iov_base + rqstp->rq_res.head[0].iov_len;
> @@ -890,6 +893,17 @@ nfsd4_proc_compound(struct svc_rqst *rqstp,
>  	if (cstate == NULL)
>  		goto out;
>  
> +#if defined(CONFIG_NFSD_V4_1)
> +	if (args->minorversion == 1) {
> +		/* FIXME: use kmem_cache */
> +		current_ses = kzalloc(sizeof(*current_ses), GFP_KERNEL);
> +		if (current_ses == NULL)
> +			goto out_free;
> +	}
> +	/* DM: current_ses must be NULL for minorversion 0 */
> +	cstate->current_ses = current_ses;
> +#endif /* CONFIG_NFSD_V4_1 */
> +
>  	status = nfs_ok;
>  	while (!status && resp->opcnt < args->opcnt) {
>  		op = &args->ops[resp->opcnt++];
> @@ -961,7 +975,15 @@ encode_op:
>  
>  		nfsd4_increment_op_stats(op->opnum);
>  	}
> -
> +out_free:
> +#if defined(CONFIG_NFSD_V4_1)
> +	if (current_ses) {
> +		struct nfs41_slot *cs_slot = current_ses->cs_slot;
> +		if (cs_slot)
> +			nfs41_put_session(cs_slot->sl_session);
> +		kfree(current_ses);
> +	}
> +#endif /* CONFIG_NFSD_V4_1 */
>  	cstate_free(cstate);
>  out:
>  	nfsd4_release_compoundargs(args);
> diff --git a/include/linux/nfsd/state.h b/include/linux/nfsd/state.h
> index 28c42ea..7684188 100644
> --- a/include/linux/nfsd/state.h
> +++ b/include/linux/nfsd/state.h
> @@ -168,6 +168,18 @@ nfs41_get_session(struct nfs41_session *ses)
>  {
>  	kref_get(&ses->se_ref);
>  }
> +
> +/* formatted contents of nfs41_sessionid */
> +struct nfsd_sessionid {
> +	clientid_t	clientid;
> +	u32		boot_time;
> +	u32		sequence;
> +};
> +
> +struct current_session {
> +	struct nfsd_sessionid	cs_sid;
> +	struct nfs41_slot	*cs_slot;
> +};
>  #endif /* CONFIG_NFSD_V4_1 */
>  
>  #define HEXDIR_LEN     33 /* hex version of 16 byte md5 of cl_name plus '\0' */
> diff --git a/include/linux/nfsd/xdr4.h b/include/linux/nfsd/xdr4.h
> index 27bd3e3..88f7cd6 100644
> --- a/include/linux/nfsd/xdr4.h
> +++ b/include/linux/nfsd/xdr4.h
> @@ -48,6 +48,9 @@ struct nfsd4_compound_state {
>  	struct svc_fh current_fh;
>  	struct svc_fh save_fh;
>  	struct nfs4_stateowner *replay_owner;
> +#if defined(CONFIG_NFSD_V4_1)
> +	struct current_session *current_ses;
> +#endif /* CONFIG_NFSD_V4_1 */
>  };
>  
>  struct nfsd4_change_info {