Commit 985d022d authored by Chuck Lever's avatar Chuck Lever
Browse files

lockd: Use xdrgen XDR functions for the NLMv4 UNSHARE procedure 



Now that the share helpers have been decoupled from the
NLMv3-specific struct nlm_args and file_lock initialization
has been hoisted into the procedure handler, the NLMv4 UNSHARE
procedure can be converted to use xdrgen-generated XDR
functions.

Replace the NLMPROC4_UNSHARE entry in the nlm_procedures4
array with an entry that uses xdrgen-built XDR decoders and
encoders. The procedure handler is updated to use the new
wrapper structures (nlm4_shareargs_wrapper and
nlm4_shareres_wrapper) and access arguments through the
argp->xdrgen hierarchy.

The .pc_argzero field is set to zero because xdrgen decoders
fully initialize all fields in argp->xdrgen, making the early
defensive memset unnecessary. The remaining argp fields that
fall outside the xdrgen structures are cleared explicitly as
needed.

Reviewed-by: default avatarJeff Layton <jlayton@kernel.org>
Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
parent 57c7bb3b

fs/lockd/svc4proc.c

+62 −36
Original line number Diff line number Diff line
@@ -1124,44 +1124,70 @@ static __be32 nlm4svc_proc_share(struct svc_rqst *rqstp) 
		rpc_drop_reply : rpc_success;

}



/*

 * UNSHARE: Release a DOS share.

/**

 * nlm4svc_proc_unshare - UNSHARE: Release a share reservation

 * @rqstp: RPC transaction context

 *

 * Returns:

 *   %rpc_success:		RPC executed successfully.

 *   %rpc_drop_reply:		Do not send an RPC reply.

 *

 * RPC synopsis:

 *   nlm4_shareres NLMPROC4_UNSHARE(nlm4_shareargs) = 21;

 *

 * Permissible procedure status codes:

 *   %NLM4_GRANTED:		The share reservation was released.

 *   %NLM4_DENIED_GRACE_PERIOD:	The server has recently restarted and is

 *				re-establishing existing locks, and is not

 *				yet ready to accept normal service requests.

 *

 * The Linux NLM server implementation also returns:

 *   %NLM4_DENIED_NOLOCKS:	A needed resource could not be allocated.

 *   %NLM4_STALE_FH:		The request specified an invalid file handle.

 *   %NLM4_FBIG:		The request specified a length or offset

 *				that exceeds the range supported by the

 *				server.

 *   %NLM4_FAILED:		The request failed for an unspecified reason.

 */

static __be32

nlm4svc_proc_unshare(struct svc_rqst *rqstp)

static __be32 nlm4svc_proc_unshare(struct svc_rqst *rqstp)

{

	struct nlm_args *argp = rqstp->rq_argp;

	struct nlm_res *resp = rqstp->rq_resp;

	struct nlm4_shareargs_wrapper *argp = rqstp->rq_argp;

	struct nlm4_shareres_wrapper *resp = rqstp->rq_resp;

	struct nlm_lock	*lock = &argp->lock;

	struct nlm_host	*host;

	struct nlm_file	*file;

	struct nlm4_lock xdr_lock = {

		.fh		= argp->xdrgen.share.fh,

		.oh		= argp->xdrgen.share.oh,

		.svid		= ~(u32)0,

	};

	struct nlm_host	*host = NULL;

	struct nlm_file	*file = NULL;



	dprintk("lockd: UNSHARE       called\n");

	resp->xdrgen.cookie = argp->xdrgen.cookie;



	resp->cookie = argp->cookie;

	resp->xdrgen.stat = nlm_lck_denied_grace_period;

	if (locks_in_grace(SVC_NET(rqstp)))

		goto out;



	/* Don't accept requests during grace period */

	if (locks_in_grace(SVC_NET(rqstp))) {

		resp->status = nlm_lck_denied_grace_period;

		return rpc_success;

	}

	resp->xdrgen.stat = nlm_lck_denied_nolocks;

	host = nlm4svc_lookup_host(rqstp, argp->xdrgen.share.caller_name, true);

	if (!host)

		goto out;



	/* Obtain client and file */

	locks_init_lock(&lock->fl);

	lock->svid = ~(u32)0;

	resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file);

	if (resp->status)

		return resp->status == nlm__int__drop_reply ?

			rpc_drop_reply : rpc_success;

	resp->xdrgen.stat = nlm4svc_lookup_file(rqstp, host, lock, &file,

						&xdr_lock, F_RDLCK);

	if (resp->xdrgen.stat)

		goto out;



	/* Now try to unshare the file */

	resp->status = nlmsvc_unshare_file(host, file, &lock->oh);

	resp->xdrgen.stat = nlmsvc_unshare_file(host, file, &lock->oh);



	dprintk("lockd: UNSHARE       status %d\n", ntohl(resp->status));

	nlmsvc_release_lockowner(lock);

	nlmsvc_release_host(host);



out:

	if (file)

		nlm_release_file(file);

	return rpc_success;

	nlmsvc_release_host(host);

	return resp->xdrgen.stat == nlm__int__drop_reply ?

		rpc_drop_reply : rpc_success;

}



/*
@@ -1419,14 +1445,14 @@ static const struct svc_procedure nlm4svc_procedures[24] = { 
		.pc_xdrressize	= NLM4_nlm4_shareres_sz,

		.pc_name	= "SHARE",

	},

	[NLMPROC_UNSHARE] = {

	[NLMPROC4_UNSHARE] = {

		.pc_func	= nlm4svc_proc_unshare,

		.pc_decode = nlm4svc_decode_shareargs,

		.pc_encode = nlm4svc_encode_shareres,

		.pc_argsize = sizeof(struct nlm_args),

		.pc_argzero = sizeof(struct nlm_args),

		.pc_ressize = sizeof(struct nlm_res),

		.pc_xdrressize = Ck+St+1,

		.pc_decode	= nlm4_svc_decode_nlm4_shareargs,

		.pc_encode	= nlm4_svc_encode_nlm4_shareres,

		.pc_argsize	= sizeof(struct nlm4_shareargs_wrapper),

		.pc_argzero	= 0,

		.pc_ressize	= sizeof(struct nlm4_shareres_wrapper),

		.pc_xdrressize	= NLM4_nlm4_shareres_sz,

		.pc_name	= "UNSHARE",

	},

	[NLMPROC_NM_LOCK] = {