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Diffstat (limited to 'kernel/net/sunrpc/xprtrdma/svc_rdma_sendto.c')
-rw-r--r--kernel/net/sunrpc/xprtrdma/svc_rdma_sendto.c560
1 files changed, 560 insertions, 0 deletions
diff --git a/kernel/net/sunrpc/xprtrdma/svc_rdma_sendto.c b/kernel/net/sunrpc/xprtrdma/svc_rdma_sendto.c
new file mode 100644
index 000000000..7de33d1af
--- /dev/null
+++ b/kernel/net/sunrpc/xprtrdma/svc_rdma_sendto.c
@@ -0,0 +1,560 @@
+/*
+ * Copyright (c) 2014 Open Grid Computing, Inc. All rights reserved.
+ * 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/debug.h>
+#include <linux/sunrpc/rpc_rdma.h>
+#include <linux/spinlock.h>
+#include <asm/unaligned.h>
+#include <rdma/ib_verbs.h>
+#include <rdma/rdma_cm.h>
+#include <linux/sunrpc/svc_rdma.h>
+
+#define RPCDBG_FACILITY RPCDBG_SVCXPRT
+
+static int map_xdr(struct svcxprt_rdma *xprt,
+ struct xdr_buf *xdr,
+ struct svc_rdma_req_map *vec)
+{
+ int sge_no;
+ u32 sge_bytes;
+ u32 page_bytes;
+ u32 page_off;
+ int page_no;
+
+ if (xdr->len !=
+ (xdr->head[0].iov_len + xdr->page_len + xdr->tail[0].iov_len)) {
+ pr_err("svcrdma: map_xdr: XDR buffer length error\n");
+ return -EIO;
+ }
+
+ /* Skip the first sge, this is for the RPCRDMA header */
+ sge_no = 1;
+
+ /* Head SGE */
+ vec->sge[sge_no].iov_base = xdr->head[0].iov_base;
+ vec->sge[sge_no].iov_len = xdr->head[0].iov_len;
+ sge_no++;
+
+ /* pages SGE */
+ page_no = 0;
+ page_bytes = xdr->page_len;
+ page_off = xdr->page_base;
+ while (page_bytes) {
+ vec->sge[sge_no].iov_base =
+ page_address(xdr->pages[page_no]) + page_off;
+ sge_bytes = min_t(u32, page_bytes, (PAGE_SIZE - page_off));
+ page_bytes -= sge_bytes;
+ vec->sge[sge_no].iov_len = sge_bytes;
+
+ sge_no++;
+ page_no++;
+ page_off = 0; /* reset for next time through loop */
+ }
+
+ /* Tail SGE */
+ if (xdr->tail[0].iov_len) {
+ vec->sge[sge_no].iov_base = xdr->tail[0].iov_base;
+ vec->sge[sge_no].iov_len = xdr->tail[0].iov_len;
+ sge_no++;
+ }
+
+ dprintk("svcrdma: map_xdr: sge_no %d page_no %d "
+ "page_base %u page_len %u head_len %zu tail_len %zu\n",
+ sge_no, page_no, xdr->page_base, xdr->page_len,
+ xdr->head[0].iov_len, xdr->tail[0].iov_len);
+
+ vec->count = sge_no;
+ return 0;
+}
+
+static dma_addr_t dma_map_xdr(struct svcxprt_rdma *xprt,
+ struct xdr_buf *xdr,
+ u32 xdr_off, size_t len, int dir)
+{
+ struct page *page;
+ dma_addr_t dma_addr;
+ if (xdr_off < xdr->head[0].iov_len) {
+ /* This offset is in the head */
+ xdr_off += (unsigned long)xdr->head[0].iov_base & ~PAGE_MASK;
+ page = virt_to_page(xdr->head[0].iov_base);
+ } else {
+ xdr_off -= xdr->head[0].iov_len;
+ if (xdr_off < xdr->page_len) {
+ /* This offset is in the page list */
+ xdr_off += xdr->page_base;
+ page = xdr->pages[xdr_off >> PAGE_SHIFT];
+ xdr_off &= ~PAGE_MASK;
+ } else {
+ /* This offset is in the tail */
+ xdr_off -= xdr->page_len;
+ xdr_off += (unsigned long)
+ xdr->tail[0].iov_base & ~PAGE_MASK;
+ page = virt_to_page(xdr->tail[0].iov_base);
+ }
+ }
+ dma_addr = ib_dma_map_page(xprt->sc_cm_id->device, page, xdr_off,
+ min_t(size_t, PAGE_SIZE, len), dir);
+ return dma_addr;
+}
+
+/* Assumptions:
+ * - The specified write_len can be represented in sc_max_sge * PAGE_SIZE
+ */
+static int send_write(struct svcxprt_rdma *xprt, struct svc_rqst *rqstp,
+ u32 rmr, u64 to,
+ u32 xdr_off, int write_len,
+ struct svc_rdma_req_map *vec)
+{
+ struct ib_send_wr write_wr;
+ struct ib_sge *sge;
+ int xdr_sge_no;
+ int sge_no;
+ int sge_bytes;
+ int sge_off;
+ int bc;
+ struct svc_rdma_op_ctxt *ctxt;
+
+ if (vec->count > RPCSVC_MAXPAGES) {
+ pr_err("svcrdma: Too many pages (%lu)\n", vec->count);
+ return -EIO;
+ }
+
+ dprintk("svcrdma: RDMA_WRITE rmr=%x, to=%llx, xdr_off=%d, "
+ "write_len=%d, vec->sge=%p, vec->count=%lu\n",
+ rmr, (unsigned long long)to, xdr_off,
+ write_len, vec->sge, vec->count);
+
+ ctxt = svc_rdma_get_context(xprt);
+ ctxt->direction = DMA_TO_DEVICE;
+ sge = ctxt->sge;
+
+ /* Find the SGE associated with xdr_off */
+ for (bc = xdr_off, xdr_sge_no = 1; bc && xdr_sge_no < vec->count;
+ xdr_sge_no++) {
+ if (vec->sge[xdr_sge_no].iov_len > bc)
+ break;
+ bc -= vec->sge[xdr_sge_no].iov_len;
+ }
+
+ sge_off = bc;
+ bc = write_len;
+ sge_no = 0;
+
+ /* Copy the remaining SGE */
+ while (bc != 0) {
+ sge_bytes = min_t(size_t,
+ bc, vec->sge[xdr_sge_no].iov_len-sge_off);
+ sge[sge_no].length = sge_bytes;
+ sge[sge_no].addr =
+ dma_map_xdr(xprt, &rqstp->rq_res, xdr_off,
+ sge_bytes, DMA_TO_DEVICE);
+ xdr_off += sge_bytes;
+ if (ib_dma_mapping_error(xprt->sc_cm_id->device,
+ sge[sge_no].addr))
+ goto err;
+ atomic_inc(&xprt->sc_dma_used);
+ sge[sge_no].lkey = xprt->sc_dma_lkey;
+ ctxt->count++;
+ sge_off = 0;
+ sge_no++;
+ xdr_sge_no++;
+ if (xdr_sge_no > vec->count) {
+ pr_err("svcrdma: Too many sges (%d)\n", xdr_sge_no);
+ goto err;
+ }
+ bc -= sge_bytes;
+ if (sge_no == xprt->sc_max_sge)
+ break;
+ }
+
+ /* Prepare WRITE WR */
+ memset(&write_wr, 0, sizeof write_wr);
+ ctxt->wr_op = IB_WR_RDMA_WRITE;
+ write_wr.wr_id = (unsigned long)ctxt;
+ write_wr.sg_list = &sge[0];
+ write_wr.num_sge = sge_no;
+ write_wr.opcode = IB_WR_RDMA_WRITE;
+ write_wr.send_flags = IB_SEND_SIGNALED;
+ write_wr.wr.rdma.rkey = rmr;
+ write_wr.wr.rdma.remote_addr = to;
+
+ /* Post It */
+ atomic_inc(&rdma_stat_write);
+ if (svc_rdma_send(xprt, &write_wr))
+ goto err;
+ return write_len - bc;
+ err:
+ svc_rdma_unmap_dma(ctxt);
+ svc_rdma_put_context(ctxt, 0);
+ /* Fatal error, close transport */
+ return -EIO;
+}
+
+static int send_write_chunks(struct svcxprt_rdma *xprt,
+ struct rpcrdma_msg *rdma_argp,
+ struct rpcrdma_msg *rdma_resp,
+ struct svc_rqst *rqstp,
+ struct svc_rdma_req_map *vec)
+{
+ u32 xfer_len = rqstp->rq_res.page_len + rqstp->rq_res.tail[0].iov_len;
+ int write_len;
+ u32 xdr_off;
+ int chunk_off;
+ int chunk_no;
+ struct rpcrdma_write_array *arg_ary;
+ struct rpcrdma_write_array *res_ary;
+ int ret;
+
+ arg_ary = svc_rdma_get_write_array(rdma_argp);
+ if (!arg_ary)
+ return 0;
+ res_ary = (struct rpcrdma_write_array *)
+ &rdma_resp->rm_body.rm_chunks[1];
+
+ /* Write chunks start at the pagelist */
+ for (xdr_off = rqstp->rq_res.head[0].iov_len, chunk_no = 0;
+ xfer_len && chunk_no < arg_ary->wc_nchunks;
+ chunk_no++) {
+ struct rpcrdma_segment *arg_ch;
+ u64 rs_offset;
+
+ arg_ch = &arg_ary->wc_array[chunk_no].wc_target;
+ write_len = min(xfer_len, ntohl(arg_ch->rs_length));
+
+ /* Prepare the response chunk given the length actually
+ * written */
+ xdr_decode_hyper((__be32 *)&arg_ch->rs_offset, &rs_offset);
+ svc_rdma_xdr_encode_array_chunk(res_ary, chunk_no,
+ arg_ch->rs_handle,
+ arg_ch->rs_offset,
+ write_len);
+ chunk_off = 0;
+ while (write_len) {
+ ret = send_write(xprt, rqstp,
+ ntohl(arg_ch->rs_handle),
+ rs_offset + chunk_off,
+ xdr_off,
+ write_len,
+ vec);
+ if (ret <= 0) {
+ dprintk("svcrdma: RDMA_WRITE failed, ret=%d\n",
+ ret);
+ return -EIO;
+ }
+ chunk_off += ret;
+ xdr_off += ret;
+ xfer_len -= ret;
+ write_len -= ret;
+ }
+ }
+ /* Update the req with the number of chunks actually used */
+ svc_rdma_xdr_encode_write_list(rdma_resp, chunk_no);
+
+ return rqstp->rq_res.page_len + rqstp->rq_res.tail[0].iov_len;
+}
+
+static int send_reply_chunks(struct svcxprt_rdma *xprt,
+ struct rpcrdma_msg *rdma_argp,
+ struct rpcrdma_msg *rdma_resp,
+ struct svc_rqst *rqstp,
+ struct svc_rdma_req_map *vec)
+{
+ u32 xfer_len = rqstp->rq_res.len;
+ int write_len;
+ u32 xdr_off;
+ int chunk_no;
+ int chunk_off;
+ int nchunks;
+ struct rpcrdma_segment *ch;
+ struct rpcrdma_write_array *arg_ary;
+ struct rpcrdma_write_array *res_ary;
+ int ret;
+
+ arg_ary = svc_rdma_get_reply_array(rdma_argp);
+ if (!arg_ary)
+ return 0;
+ /* XXX: need to fix when reply lists occur with read-list and or
+ * write-list */
+ res_ary = (struct rpcrdma_write_array *)
+ &rdma_resp->rm_body.rm_chunks[2];
+
+ /* xdr offset starts at RPC message */
+ nchunks = ntohl(arg_ary->wc_nchunks);
+ for (xdr_off = 0, chunk_no = 0;
+ xfer_len && chunk_no < nchunks;
+ chunk_no++) {
+ u64 rs_offset;
+ ch = &arg_ary->wc_array[chunk_no].wc_target;
+ write_len = min(xfer_len, htonl(ch->rs_length));
+
+ /* Prepare the reply chunk given the length actually
+ * written */
+ xdr_decode_hyper((__be32 *)&ch->rs_offset, &rs_offset);
+ svc_rdma_xdr_encode_array_chunk(res_ary, chunk_no,
+ ch->rs_handle, ch->rs_offset,
+ write_len);
+ chunk_off = 0;
+ while (write_len) {
+ ret = send_write(xprt, rqstp,
+ ntohl(ch->rs_handle),
+ rs_offset + chunk_off,
+ xdr_off,
+ write_len,
+ vec);
+ if (ret <= 0) {
+ dprintk("svcrdma: RDMA_WRITE failed, ret=%d\n",
+ ret);
+ return -EIO;
+ }
+ chunk_off += ret;
+ xdr_off += ret;
+ xfer_len -= ret;
+ write_len -= ret;
+ }
+ }
+ /* Update the req with the number of chunks actually used */
+ svc_rdma_xdr_encode_reply_array(res_ary, chunk_no);
+
+ return rqstp->rq_res.len;
+}
+
+/* This function prepares the portion of the RPCRDMA message to be
+ * sent in the RDMA_SEND. This function is called after data sent via
+ * RDMA has already been transmitted. There are three cases:
+ * - The RPCRDMA header, RPC header, and payload are all sent in a
+ * single RDMA_SEND. This is the "inline" case.
+ * - The RPCRDMA header and some portion of the RPC header and data
+ * are sent via this RDMA_SEND and another portion of the data is
+ * sent via RDMA.
+ * - The RPCRDMA header [NOMSG] is sent in this RDMA_SEND and the RPC
+ * header and data are all transmitted via RDMA.
+ * In all three cases, this function prepares the RPCRDMA header in
+ * sge[0], the 'type' parameter indicates the type to place in the
+ * RPCRDMA header, and the 'byte_count' field indicates how much of
+ * the XDR to include in this RDMA_SEND. NB: The offset of the payload
+ * to send is zero in the XDR.
+ */
+static int send_reply(struct svcxprt_rdma *rdma,
+ struct svc_rqst *rqstp,
+ struct page *page,
+ struct rpcrdma_msg *rdma_resp,
+ struct svc_rdma_op_ctxt *ctxt,
+ struct svc_rdma_req_map *vec,
+ int byte_count)
+{
+ struct ib_send_wr send_wr;
+ int sge_no;
+ int sge_bytes;
+ int page_no;
+ int pages;
+ int ret;
+
+ /* Post a recv buffer to handle another request. */
+ ret = svc_rdma_post_recv(rdma);
+ if (ret) {
+ printk(KERN_INFO
+ "svcrdma: could not post a receive buffer, err=%d."
+ "Closing transport %p.\n", ret, rdma);
+ set_bit(XPT_CLOSE, &rdma->sc_xprt.xpt_flags);
+ svc_rdma_put_context(ctxt, 0);
+ return -ENOTCONN;
+ }
+
+ /* Prepare the context */
+ ctxt->pages[0] = page;
+ ctxt->count = 1;
+
+ /* Prepare the SGE for the RPCRDMA Header */
+ ctxt->sge[0].lkey = rdma->sc_dma_lkey;
+ ctxt->sge[0].length = svc_rdma_xdr_get_reply_hdr_len(rdma_resp);
+ ctxt->sge[0].addr =
+ ib_dma_map_page(rdma->sc_cm_id->device, page, 0,
+ ctxt->sge[0].length, DMA_TO_DEVICE);
+ if (ib_dma_mapping_error(rdma->sc_cm_id->device, ctxt->sge[0].addr))
+ goto err;
+ atomic_inc(&rdma->sc_dma_used);
+
+ ctxt->direction = DMA_TO_DEVICE;
+
+ /* Map the payload indicated by 'byte_count' */
+ for (sge_no = 1; byte_count && sge_no < vec->count; sge_no++) {
+ int xdr_off = 0;
+ sge_bytes = min_t(size_t, vec->sge[sge_no].iov_len, byte_count);
+ byte_count -= sge_bytes;
+ ctxt->sge[sge_no].addr =
+ dma_map_xdr(rdma, &rqstp->rq_res, xdr_off,
+ sge_bytes, DMA_TO_DEVICE);
+ xdr_off += sge_bytes;
+ if (ib_dma_mapping_error(rdma->sc_cm_id->device,
+ ctxt->sge[sge_no].addr))
+ goto err;
+ atomic_inc(&rdma->sc_dma_used);
+ ctxt->sge[sge_no].lkey = rdma->sc_dma_lkey;
+ ctxt->sge[sge_no].length = sge_bytes;
+ }
+ if (byte_count != 0) {
+ pr_err("svcrdma: Could not map %d bytes\n", byte_count);
+ goto err;
+ }
+
+ /* Save all respages in the ctxt and remove them from the
+ * respages array. They are our pages until the I/O
+ * completes.
+ */
+ pages = rqstp->rq_next_page - rqstp->rq_respages;
+ for (page_no = 0; page_no < pages; page_no++) {
+ ctxt->pages[page_no+1] = rqstp->rq_respages[page_no];
+ ctxt->count++;
+ rqstp->rq_respages[page_no] = NULL;
+ /*
+ * If there are more pages than SGE, terminate SGE
+ * list so that svc_rdma_unmap_dma doesn't attempt to
+ * unmap garbage.
+ */
+ if (page_no+1 >= sge_no)
+ ctxt->sge[page_no+1].length = 0;
+ }
+ rqstp->rq_next_page = rqstp->rq_respages + 1;
+
+ if (sge_no > rdma->sc_max_sge) {
+ pr_err("svcrdma: Too many sges (%d)\n", sge_no);
+ goto err;
+ }
+ memset(&send_wr, 0, sizeof send_wr);
+ ctxt->wr_op = IB_WR_SEND;
+ send_wr.wr_id = (unsigned long)ctxt;
+ send_wr.sg_list = ctxt->sge;
+ send_wr.num_sge = sge_no;
+ send_wr.opcode = IB_WR_SEND;
+ send_wr.send_flags = IB_SEND_SIGNALED;
+
+ ret = svc_rdma_send(rdma, &send_wr);
+ if (ret)
+ goto err;
+
+ return 0;
+
+ err:
+ svc_rdma_unmap_dma(ctxt);
+ svc_rdma_put_context(ctxt, 1);
+ return -EIO;
+}
+
+void svc_rdma_prep_reply_hdr(struct svc_rqst *rqstp)
+{
+}
+
+int svc_rdma_sendto(struct svc_rqst *rqstp)
+{
+ struct svc_xprt *xprt = rqstp->rq_xprt;
+ struct svcxprt_rdma *rdma =
+ container_of(xprt, struct svcxprt_rdma, sc_xprt);
+ struct rpcrdma_msg *rdma_argp;
+ struct rpcrdma_msg *rdma_resp;
+ struct rpcrdma_write_array *reply_ary;
+ enum rpcrdma_proc reply_type;
+ int ret;
+ int inline_bytes;
+ struct page *res_page;
+ struct svc_rdma_op_ctxt *ctxt;
+ struct svc_rdma_req_map *vec;
+
+ dprintk("svcrdma: sending response for rqstp=%p\n", rqstp);
+
+ /* Get the RDMA request header. The receive logic always
+ * places this at the start of page 0.
+ */
+ rdma_argp = page_address(rqstp->rq_pages[0]);
+
+ /* Build an req vec for the XDR */
+ ctxt = svc_rdma_get_context(rdma);
+ ctxt->direction = DMA_TO_DEVICE;
+ vec = svc_rdma_get_req_map();
+ ret = map_xdr(rdma, &rqstp->rq_res, vec);
+ if (ret)
+ goto err0;
+ inline_bytes = rqstp->rq_res.len;
+
+ /* Create the RDMA response header */
+ res_page = svc_rdma_get_page();
+ rdma_resp = page_address(res_page);
+ reply_ary = svc_rdma_get_reply_array(rdma_argp);
+ if (reply_ary)
+ reply_type = RDMA_NOMSG;
+ else
+ reply_type = RDMA_MSG;
+ svc_rdma_xdr_encode_reply_header(rdma, rdma_argp,
+ rdma_resp, reply_type);
+
+ /* Send any write-chunk data and build resp write-list */
+ ret = send_write_chunks(rdma, rdma_argp, rdma_resp,
+ rqstp, vec);
+ if (ret < 0) {
+ printk(KERN_ERR "svcrdma: failed to send write chunks, rc=%d\n",
+ ret);
+ goto err1;
+ }
+ inline_bytes -= ret;
+
+ /* Send any reply-list data and update resp reply-list */
+ ret = send_reply_chunks(rdma, rdma_argp, rdma_resp,
+ rqstp, vec);
+ if (ret < 0) {
+ printk(KERN_ERR "svcrdma: failed to send reply chunks, rc=%d\n",
+ ret);
+ goto err1;
+ }
+ inline_bytes -= ret;
+
+ ret = send_reply(rdma, rqstp, res_page, rdma_resp, ctxt, vec,
+ inline_bytes);
+ svc_rdma_put_req_map(vec);
+ dprintk("svcrdma: send_reply returns %d\n", ret);
+ return ret;
+
+ err1:
+ put_page(res_page);
+ err0:
+ svc_rdma_put_req_map(vec);
+ svc_rdma_put_context(ctxt, 0);
+ return ret;
+}