/*
* Copyright (c) 2005-2006 Network Appliance, Inc. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the BSD-type
* license below:
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* Neither the name of the Network Appliance, Inc. nor the names of
* its contributors may be used to endorse or promote products
* derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Author: Tom Tucker <tom@opengridcomputing.com>
*/
#include <linux/sunrpc/xdr.h>
#include <linux/sunrpc/debug.h>
#include <asm/unaligned.h>
#include <linux/sunrpc/rpc_rdma.h>
#include <linux/sunrpc/svc_rdma.h>
#define RPCDBG_FACILITY RPCDBG_SVCXPRT
/*
* Decodes a read chunk list. The expected format is as follows:
* descrim : xdr_one
* position : u32 offset into XDR stream
* handle : u32 RKEY
* . . .
* end-of-list: xdr_zero
*/
static u32 *decode_read_list(u32 *va, u32 *vaend)
{
struct rpcrdma_read_chunk *ch = (struct rpcrdma_read_chunk *)va;
while (ch->rc_discrim != xdr_zero) {
if (((unsigned long)ch + sizeof(struct rpcrdma_read_chunk)) >
(unsigned long)vaend) {
dprintk("svcrdma: vaend=%p, ch=%p\n", vaend, ch);
return NULL;
}
ch++;
}
return (u32 *)&ch->rc_position;
}
/*
* Determine number of chunks and total bytes in chunk list. The chunk
* list has already been verified to fit within the RPCRDMA header.
*/
void svc_rdma_rcl_chunk_counts(struct rpcrdma_read_chunk *ch,
int *ch_count, int *byte_count)
{
/* compute the number of bytes represented by read chunks */
*byte_count = 0;
*ch_count = 0;
for (; ch->rc_discrim != 0; ch++) {
*byte_count = *byte_count + ntohl(ch->rc_target.rs_length);
*ch_count = *ch_count + 1;
}
}
/*
* Decodes a write chunk list. The expected format is as follows:
* descrim : xdr_one
* nchunks : <count>
* handle : u32 RKEY ---+
* length : u32 <len of segment> |
* offset : remove va + <count>
* . . . |
* ---+
*/
static u32 *decode_write_list(u32 *va, u32 *vaend)
{
int nchunks;
struct rpcrdma_write_array *ary =
(struct rpcrdma_write_array *)va;
/* Check for not write-array */
if (ary->wc_discrim == xdr_zero)
return (u32 *)&ary->wc_nchunks;
if ((unsigned long)ary + sizeof(struct rpcrdma_write_array) >
(unsigned long)vaend) {
dprintk("svcrdma: ary=%p, vaend=%p\n", ary, vaend);
return NULL;
}
nchunks = ntohl(ary->wc_nchunks);
if (((unsigned long)&ary->wc_array[0] +
(sizeof(struct rpcrdma_write_chunk) * nchunks)) >
(unsigned long)vaend) {
dprintk("svcrdma: ary=%p, wc_nchunks=%d, vaend=%p\n",
ary, nchunks, vaend);
return NULL;
}
/*
* rs_length is the 2nd 4B field in wc_target and taking its
* address skips the list terminator
*/
return (u32 *)&ary->wc_array[nchunks].wc_target.rs_length;
}
static u32 *decode_reply_array(u32 *va, u32 *vaend)
{
int nchunks;
struct rpcrdma_write_array *ary =
(struct rpcrdma_write_array *)va;
/* Check for no reply-array */
if (ary->wc_discrim == xdr_zero)
return (u32 *)&ary->wc_nchunks;
if ((unsigned long)ary + sizeof(struct rpcrdma_write_array) >
(unsigned long)vaend) {
dprintk("svcrdma: ary=%p, vaend=%p\n", ary, vaend);
return NULL;
}
nchunks = ntohl(ary->wc_nchunks);
if (((unsigned long)&ary->wc_array[0] +
(sizeof(struct rpcrdma_write_chunk) * nchunks)) >
(unsigned long)vaend) {
dprintk("svcrdma: ary=%p, wc_nchunks=%d, vaend=%p\n",
ary, nchunks, vaend);
return NULL;
}
return (u32 *)&ary->wc_array[nchunks];
}
int svc_rdma_xdr_decode_req(struct rpcrdma_msg **rdma_req,
struct svc_rqst *rqstp)
{
struct rpcrdma_msg *rmsgp = NULL;
u32 *va;
u32 *vaend;
u32 hdr_len;
rmsgp = (struct rpcrdma_msg *)rqstp->rq_arg.head[0].iov_base;
/* Verify that there's enough bytes for header + something */
if (rqstp->rq_arg.len <= RPCRDMA_HDRLEN_MIN) {
dprintk("svcrdma: header too short = %d\n",
rqstp->rq_arg.len);
return -EINVAL;
}
/* Decode the header */
rmsgp->rm_xid = ntohl(rmsgp->rm_xid);
rmsgp->rm_vers = ntohl(rmsgp->rm_vers);
rmsgp->rm_credit = ntohl(rmsgp->rm_credit);
rmsgp->rm_type = ntohl(rmsgp->rm_type);
if (rmsgp->rm_vers != RPCRDMA_VERSION)
return -ENOSYS;
/* Pull in the extra for the padded case and bump our pointer */
if (rmsgp->rm_type == RDMA_MSGP) {
int hdrlen;
rmsgp->rm_body.rm_padded.rm_align =
ntohl(rmsgp->rm_body.rm_padded.rm_align);
rmsgp->rm_body.rm_padded.rm_thresh =
ntohl(rmsgp->rm_body.rm_padded.rm_thresh);
va = &rmsgp->rm_body.rm_padded.rm_pempty[4];
rqstp->rq_arg.head[0].iov_base = va;
hdrlen = (u32)((unsigned long)va - (unsigned long)rmsgp);
rqstp->rq_arg.head[0].iov_len -= hdrlen;
if (hdrlen > rqstp->rq_arg.len)
return -EINVAL;
return hdrlen;
}
/* The chunk list may contain either a read chunk list or a write
* chunk list and a reply chunk list.
*/
va = &rmsgp->rm_body.rm_chunks[0];
vaend = (u32 *)((unsigned long)rmsgp + rqstp->rq_arg.len);
va = decode_read_list(va, vaend);
if (!va)
return -EINVAL;
va = decode_write_list(va, vaend);
if (!va)
return -EINVAL;
va = decode_reply_array(va, vaend);
if (!va)
return -EINVAL;
rqstp->rq_arg.head[0].iov_base = va;
hdr_len = (unsigned long)va - (unsigned long)rmsgp;
rqstp->rq_arg.head[0].iov_len -= hdr_len;
*rdma_req = rmsgp;
return hdr_len;
}
int svc_rdma_xdr_decode_deferred_req(struct svc_rqst *rqstp)
{
struct rpcrdma_msg *rmsgp = NULL;
struct rpcrdma_read_chunk *ch;
struct rpcrdma_write_array *ary;
u32 *va;
u32 hdrlen;
dprintk("svcrdma: processing deferred RDMA header on rqstp=%p\n",
rqstp);
rmsgp = (struct rpcrdma_msg *)rqstp->rq_arg.head[0].iov_base;
/* Pull in the extra for the padded case and bump our pointer */
if (rmsgp->rm_type == RDMA_MSGP) {
va = &rmsgp->rm_body.rm_padded.rm_pempty[4];
rqstp->rq_arg.head[0].iov_base = va;
hdrlen = (u32)((unsigned long)va - (unsigned long)rmsgp);
rqstp->rq_arg.head[0].iov_len -= hdrlen;
return hdrlen;
}
/*
* Skip all chunks to find RPC msg. These were previously processed
*/
va = &rmsgp->rm_body.rm_chunks[0];
/* Skip read-list */
for (ch = (struct rpcrdma_read_chunk *)va;
ch->rc_discrim != xdr_zero; ch++);
va = (u32 *)&ch->rc_position;
/* Skip write-list */
ary = (struct rpcrdma_write_array *)va;
if (ary->wc_discrim == xdr_zero)
va = (u32 *)&ary->wc_nchunks;
else
/*
* rs_length is the 2nd 4B field in wc_target and taking its
* address skips the list terminator
*/
va = (u32 *)&ary->wc_array[ary->wc_nchunks].wc_target.rs_length;
/* Skip reply-array */
ary = (struct rpcrdma_write_array *)va;
if (ary->wc_discrim == xdr_zero)
va = (u32 *)&ary->wc_nchunks;
else
va = (u32 *)&ary->wc_array[ary->wc_nchunks];
rqstp->rq_arg.head[0].iov_base = va;
hdrlen = (unsigned long)va - (unsigned long)rmsgp;
rqstp->rq_arg.head[0].iov_len -= hdrlen;
return hdrlen;
}
int svc_rdma_xdr_encode_error(struct svcxprt_rdma *xprt,
struct rpcrdma_msg *rmsgp,
enum rpcrdma_errcode err, u32 *va)
{
u32 *startp = va;
*va++ = htonl(rmsgp->rm_xid);
*va++ = htonl(rmsgp->rm_vers);
*va++ = htonl(xprt->sc_max_requests);
*va++ = htonl(RDMA_ERROR);
*va++ = htonl(err);
if (err == ERR_VERS) {
*va++ = htonl(RPCRDMA_VERSION);
*va++ = htonl(RPCRDMA_VERSION);
}
return (int)((unsigned long)va - (unsigned long)startp);
}
int svc_rdma_xdr_get_reply_hdr_len(struct rpcrdma_msg *rmsgp)
{
struct rpcrdma_write_array *wr_ary;
/* There is no read-list in a reply */
/* skip write list */
wr_ary = (struct rpcrdma_write_array *)
&rmsgp->rm_body.rm_chunks[1];
if (wr_ary->wc_discrim)
wr_ary = (struct rpcrdma_write_array *)
&wr_ary->wc_array[ntohl(wr_ary->wc_nchunks)].
wc_target.rs_length;
else
wr_ary = (struct rpcrdma_write_array *)
&wr_ary->wc_nchunks;
/* skip reply array */
if (wr_ary->wc_discrim)
wr_ary = (struct rpcrdma_write_array *)
&wr_ary->wc_array[ntohl(wr_ary->wc_nchunks)];
else
wr_ary = (struct rpcrdma_write_array *)
&wr_ary->wc_nchunks;
return (unsigned long) wr_ary - (unsigned long) rmsgp;
}
void svc_rdma_xdr_encode_write_list(struct rpcrdma_msg *rmsgp, int chunks)
{
struct rpcrdma_write_array *ary;
/* no read-list */
rmsgp->rm_body.rm_chunks[0] = xdr_zero;
/* write-array discrim */
ary = (struct rpcrdma_write_array *)
&rmsgp->rm_body.rm_chunks[1];
ary->wc_discrim = xdr_one;
ary->wc_nchunks = htonl(chunks);
/* write-list terminator */
ary->wc_array[chunks].wc_target.rs_handle = xdr_zero;
/* reply-array discriminator */
ary->wc_array[chunks].wc_target.rs_length = xdr_zero;
}
void svc_rdma_xdr_encode_reply_array(struct rpcrdma_write_array *ary,
int chunks)
{
ary->wc_discrim = xdr_one;
ary->wc_nchunks = htonl(chunks);
}
void svc_rdma_xdr_encode_array_chunk(struct rpcrdma_write_array *ary,
int chunk_no,
__be32 rs_handle,
__be64 rs_offset,
u32 write_len)
{
struct rpcrdma_segment *seg = &ary->wc_array[chunk_no].wc_target;
seg->rs_handle = rs_handle;
seg->rs_offset = rs_offset;
seg->rs_length = htonl(write_len);
}
void svc_rdma_xdr_encode_reply_header(struct svcxprt_rdma *xprt,
struct rpcrdma_msg *rdma_argp,
struct rpcrdma_msg *rdma_resp,
enum rpcrdma_proc rdma_type)
{
rdma_resp->rm_xid = htonl(rdma_argp->rm_xid);
rdma_resp->rm_vers = htonl(rdma_argp->rm_vers);
rdma_resp->rm_credit = htonl(xprt->sc_max_requests);
rdma_resp->rm_type = htonl(rdma_type);
/* Encode <nul> chunks lists */
rdma_resp->rm_body.rm_chunks[0] = xdr_zero;
rdma_resp->rm_body.rm_chunks[1] = xdr_zero;
rdma_resp->rm_body.rm_chunks[2] = xdr_zero;
}