NFSD: Add a helper to decode nfs_impl_id4

}

static __be32

nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,

nfsd4_decode_nfs_impl_id4(struct nfsd4_compoundargs *argp,

			  struct nfsd4_exchange_id *exid)

{

	DECODE_HEAD;

	int dummy;

	__be32 status;

	u32 count;

	status = nfsd4_decode_verifier4(argp, &exid->verifier);

	if (xdr_stream_decode_u32(argp->xdr, &count) < 0)

		return nfserr_bad_xdr;

	switch (count) {

	case 0:

		break;

	case 1:

		/* Note that RFC 8881 places no length limit on

		 * nii_domain, but this implementation permits no

		 * more than NFS4_OPAQUE_LIMIT bytes */

		status = nfsd4_decode_opaque(argp, &exid->nii_domain);

		if (status)

			return status;

	status = nfsd4_decode_opaque(argp, &exid->clname);

		/* Note that RFC 8881 places no length limit on

		 * nii_name, but this implementation permits no

		 * more than NFS4_OPAQUE_LIMIT bytes */

		status = nfsd4_decode_opaque(argp, &exid->nii_name);

		if (status)

			return status;

	if (xdr_stream_decode_u32(argp->xdr, &exid->flags) < 0)

		return nfserr_bad_xdr;

	status = nfsd4_decode_state_protect4_a(argp, exid);

		status = nfsd4_decode_nfstime4(argp, &exid->nii_time);

		if (status)

			return status;

		break;

	default:

		return nfserr_bad_xdr;

	}

	READ_BUF(4);    /* nfs_impl_id4 array length */

	dummy = be32_to_cpup(p++);

	return nfs_ok;

}

	if (dummy > 1)

		goto xdr_error;

static __be32

nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,

			 struct nfsd4_exchange_id *exid)

{

	__be32 status;

	if (dummy == 1) {

		status = nfsd4_decode_opaque(argp, &exid->nii_domain);

	status = nfsd4_decode_verifier4(argp, &exid->verifier);

	if (status)

			goto xdr_error;

		/* nii_name */

		status = nfsd4_decode_opaque(argp, &exid->nii_name);

		return status;

	status = nfsd4_decode_opaque(argp, &exid->clname);

	if (status)

			goto xdr_error;

		/* nii_date */

		status = nfsd4_decode_time(argp, &exid->nii_time);

		return status;

	if (xdr_stream_decode_u32(argp->xdr, &exid->flags) < 0)

		return nfserr_bad_xdr;

	status = nfsd4_decode_state_protect4_a(argp, exid);

	if (status)

			goto xdr_error;

	}

	DECODE_TAIL;

		return status;

	return nfsd4_decode_nfs_impl_id4(argp, exid);

}

static __be32