Commit 76e5492b authored by Chuck Lever's avatar Chuck Lever
Browse files

NFSD: Invoke svc_encode_result_payload() in "read" NFSD encoders 



Have the NFSD encoders annotate the boundaries of every
direct-data-placement eligible result data payload. Then change
svcrdma to use that annotation instead of the xdr->page_len
when handling Write chunks.

For NFSv4 on RDMA, that enables the ability to recognize multiple
result payloads per compound. This is a pre-requisite for supporting
multiple Write chunks per RPC transaction.

Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
parent 03493bca

fs/nfsd/nfs3xdr.c

+7 −0
Original line number Diff line number Diff line
@@ -707,6 +707,7 @@ int 
nfs3svc_encode_readlinkres(struct svc_rqst *rqstp, __be32 *p)

{

	struct nfsd3_readlinkres *resp = rqstp->rq_resp;

	struct kvec *head = rqstp->rq_res.head;



	*p++ = resp->status;

	p = encode_post_op_attr(rqstp, p, &resp->fh);
@@ -720,6 +721,8 @@ nfs3svc_encode_readlinkres(struct svc_rqst *rqstp, __be32 *p) 
			*p = 0;

			rqstp->rq_res.tail[0].iov_len = 4 - (resp->len&3);

		}

		if (svc_encode_result_payload(rqstp, head->iov_len, resp->len))

			return 0;

		return 1;

	} else

		return xdr_ressize_check(rqstp, p);
@@ -730,6 +733,7 @@ int 
nfs3svc_encode_readres(struct svc_rqst *rqstp, __be32 *p)

{

	struct nfsd3_readres *resp = rqstp->rq_resp;

	struct kvec *head = rqstp->rq_res.head;



	*p++ = resp->status;

	p = encode_post_op_attr(rqstp, p, &resp->fh);
@@ -746,6 +750,9 @@ nfs3svc_encode_readres(struct svc_rqst *rqstp, __be32 *p) 
			*p = 0;

			rqstp->rq_res.tail[0].iov_len = 4 - (resp->count & 3);

		}

		if (svc_encode_result_payload(rqstp, head->iov_len,

					      resp->count))

			return 0;

		return 1;

	} else

		return xdr_ressize_check(rqstp, p);

fs/nfsd/nfs4xdr.c

+29 −12
Original line number Diff line number Diff line
@@ -3756,8 +3756,8 @@ static __be32 nfsd4_encode_splice_read( 
{

	struct xdr_stream *xdr = &resp->xdr;

	struct xdr_buf *buf = xdr->buf;

	int status, space_left;

	u32 eof;

	int space_left;

	__be32 nfserr;

	__be32 *p = xdr->p - 2;
@@ -3768,14 +3768,13 @@ static __be32 nfsd4_encode_splice_read( 
	nfserr = nfsd_splice_read(read->rd_rqstp, read->rd_fhp,

				  file, read->rd_offset, &maxcount, &eof);

	read->rd_length = maxcount;

	if (nfserr) {

		/*

		 * nfsd_splice_actor may have already messed with the

		 * page length; reset it so as not to confuse

		 * xdr_truncate_encode:

		 */

		buf->page_len = 0;

		return nfserr;

	if (nfserr)

		goto out_err;

	status = svc_encode_result_payload(read->rd_rqstp,

					   buf->head[0].iov_len, maxcount);

	if (status) {

		nfserr = nfserrno(status);

		goto out_err;

	}



	*(p++) = htonl(eof);
@@ -3806,6 +3805,15 @@ static __be32 nfsd4_encode_splice_read( 
	xdr->end = (__be32 *)((void *)xdr->end + space_left);



	return 0;



out_err:

	/*

	 * nfsd_splice_actor may have already messed with the

	 * page length; reset it so as not to confuse

	 * xdr_truncate_encode in our caller.

	 */

	buf->page_len = 0;

	return nfserr;

}



static __be32 nfsd4_encode_readv(struct nfsd4_compoundres *resp,
@@ -3897,6 +3905,7 @@ nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd 
	int zero = 0;

	struct xdr_stream *xdr = &resp->xdr;

	int length_offset = xdr->buf->len;

	int status;

	__be32 *p;



	p = xdr_reserve_space(xdr, 4);
@@ -3917,9 +3926,13 @@ nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd 
						(char *)p, &maxcount);

	if (nfserr == nfserr_isdir)

		nfserr = nfserr_inval;

	if (nfserr) {

		xdr_truncate_encode(xdr, length_offset);

		return nfserr;

	if (nfserr)

		goto out_err;

	status = svc_encode_result_payload(readlink->rl_rqstp, length_offset,

					   maxcount);

	if (status) {

		nfserr = nfserrno(status);

		goto out_err;

	}



	wire_count = htonl(maxcount);
@@ -3929,6 +3942,10 @@ nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd 
		write_bytes_to_xdr_buf(xdr->buf, length_offset + 4 + maxcount,

						&zero, 4 - (maxcount&3));

	return 0;



out_err:

	xdr_truncate_encode(xdr, length_offset);

	return nfserr;

}



static __be32

fs/nfsd/nfsxdr.c

+6 −0
Original line number Diff line number Diff line
@@ -469,6 +469,7 @@ int 
nfssvc_encode_readlinkres(struct svc_rqst *rqstp, __be32 *p)

{

	struct nfsd_readlinkres *resp = rqstp->rq_resp;

	struct kvec *head = rqstp->rq_res.head;



	*p++ = resp->status;

	if (resp->status != nfs_ok)
@@ -483,6 +484,8 @@ nfssvc_encode_readlinkres(struct svc_rqst *rqstp, __be32 *p) 
		*p = 0;

		rqstp->rq_res.tail[0].iov_len = 4 - (resp->len&3);

	}

	if (svc_encode_result_payload(rqstp, head->iov_len, resp->len))

		return 0;

	return 1;

}
@@ -490,6 +493,7 @@ int 
nfssvc_encode_readres(struct svc_rqst *rqstp, __be32 *p)

{

	struct nfsd_readres *resp = rqstp->rq_resp;

	struct kvec *head = rqstp->rq_res.head;



	*p++ = resp->status;

	if (resp->status != nfs_ok)
@@ -507,6 +511,8 @@ nfssvc_encode_readres(struct svc_rqst *rqstp, __be32 *p) 
		*p = 0;

		rqstp->rq_res.tail[0].iov_len = 4 - (resp->count&3);

	}

	if (svc_encode_result_payload(rqstp, head->iov_len, resp->count))

		return 0;

	return 1;

}

net/sunrpc/xprtrdma/svc_rdma_sendto.c

+7 −17
Original line number Diff line number Diff line
@@ -448,7 +448,6 @@ static ssize_t svc_rdma_encode_write_chunk(__be32 *src, 
 * svc_rdma_encode_write_list - Encode RPC Reply's Write chunk list

 * @rctxt: Reply context with information about the RPC Call

 * @sctxt: Send context for the RPC Reply

 * @length: size in bytes of the payload in the first Write chunk

 *

 * The client provides a Write chunk list in the Call message. Fill

 * in the segments in the first Write chunk in the Reply's transport
@@ -465,12 +464,12 @@ static ssize_t svc_rdma_encode_write_chunk(__be32 *src, 
 */

static ssize_t

svc_rdma_encode_write_list(const struct svc_rdma_recv_ctxt *rctxt,

			   struct svc_rdma_send_ctxt *sctxt,

			   unsigned int length)

			   struct svc_rdma_send_ctxt *sctxt)

{

	ssize_t len, ret;



	ret = svc_rdma_encode_write_chunk(rctxt->rc_write_list, sctxt, length);

	ret = svc_rdma_encode_write_chunk(rctxt->rc_write_list, sctxt,

					  rctxt->rc_read_payload_length);

	if (ret < 0)

		return ret;

	len = ret;
@@ -923,21 +922,12 @@ int svc_rdma_sendto(struct svc_rqst *rqstp) 
		goto err0;

	if (wr_lst) {

		/* XXX: Presume the client sent only one Write chunk */

		unsigned long offset;

		unsigned int length;



		if (rctxt->rc_read_payload_length) {

			offset = rctxt->rc_read_payload_offset;

			length = rctxt->rc_read_payload_length;

		} else {

			offset = xdr->head[0].iov_len;

			length = xdr->page_len;

		}

		ret = svc_rdma_send_write_chunk(rdma, wr_lst, xdr, offset,

						length);

		ret = svc_rdma_send_write_chunk(rdma, wr_lst, xdr,

						rctxt->rc_read_payload_offset,

						rctxt->rc_read_payload_length);

		if (ret < 0)

			goto err2;

		if (svc_rdma_encode_write_list(rctxt, sctxt, length) < 0)

		if (svc_rdma_encode_write_list(rctxt, sctxt) < 0)

			goto err0;

	} else {

		if (xdr_stream_encode_item_absent(&sctxt->sc_stream) < 0)