/* * 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 */ #include #include #include #include #include #include #include #define RPCDBG_FACILITY RPCDBG_SVCXPRT static u32 xdr_padsize(u32 len) { return (len & 3) ? (4 - (len & 3)) : 0; } int svc_rdma_map_xdr(struct svcxprt_rdma *xprt, struct xdr_buf *xdr, struct svc_rdma_req_map *vec, bool write_chunk_present) { 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: %s: XDR buffer length error\n", __func__); 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) { unsigned char *base = xdr->tail[0].iov_base; size_t len = xdr->tail[0].iov_len; u32 xdr_pad = xdr_padsize(xdr->page_len); if (write_chunk_present && xdr_pad) { base += xdr_pad; len -= xdr_pad; } if (len) { vec->sge[sge_no].iov_base = base; vec->sge[sge_no].iov_len = len; sge_no++; } } dprintk("svcrdma: %s: sge_no %d page_no %d " "page_base %u page_len %u head_len %zu tail_len %zu\n", __func__, 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; } /* Parse the RPC Call's transport header. */ static void svc_rdma_get_write_arrays(struct rpcrdma_msg *rmsgp, struct rpcrdma_write_array **write, struct rpcrdma_write_array **reply) { __be32 *p; p = (__be32 *)&rmsgp->rm_body.rm_chunks[0]; /* Read list */ while (*p++ != xdr_zero) p += 5; /* Write list */ if (*p != xdr_zero) { *write = (struct rpcrdma_write_array *)p; while (*p++ != xdr_zero) p += 1 + be32_to_cpu(*p) * 4; } else { *write = NULL; p++; } /* Reply chunk */ if (*p != xdr_zero) *reply = (struct rpcrdma_write_array *)p; else *reply = NULL; } /* RPC-over-RDMA Version One private extension: Remote Invalidation. * Responder's choice: requester signals it can handle Send With * Invalidate, and responder chooses one rkey to invalidate. * * Find a candidate rkey to invalidate when sending a reply. Picks the * first rkey it finds in the chunks lists. * * Returns zero if RPC's chunk lists are empty. */ static u32 svc_rdma_get_inv_rkey(struct rpcrdma_msg *rdma_argp, struct rpcrdma_write_array *wr_ary, struct rpcrdma_write_array *rp_ary) { struct rpcrdma_read_chunk *rd_ary; struct rpcrdma_segment *arg_ch; rd_ary = (struct rpcrdma_read_chunk *)&rdma_argp->rm_body.rm_chunks[0]; if (rd_ary->rc_discrim != xdr_zero) return be32_to_cpu(rd_ary->rc_target.rs_handle); if (wr_ary && be32_to_cpu(wr_ary->wc_nchunks)) { arg_ch = &wr_ary->wc_array[0].wc_target; return be32_to_cpu(arg_ch->rs_handle); } if (rp_ary && be32_to_cpu(rp_ary->wc_nchunks)) { arg_ch = &rp_ary->wc_array[0].wc_target; return be32_to_cpu(arg_ch->rs_handle); } return 0; } /* 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_rdma_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; svc_rdma_count_mappings(xprt, ctxt); sge[sge_no].lkey = xprt->sc_pd->local_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->cqe.done = svc_rdma_wc_write; write_wr.wr.wr_cqe = &ctxt->cqe; write_wr.wr.sg_list = &sge[0]; write_wr.wr.num_sge = sge_no; write_wr.wr.opcode = IB_WR_RDMA_WRITE; write_wr.wr.send_flags = IB_SEND_SIGNALED; write_wr.rkey = rmr; write_wr.remote_addr = to; /* Post It */ atomic_inc(&rdma_stat_write); if (svc_rdma_send(xprt, &write_wr.wr)) goto err; return write_len - bc; err: svc_rdma_unmap_dma(ctxt); svc_rdma_put_context(ctxt, 0); return -EIO; } noinline static int send_write_chunks(struct svcxprt_rdma *xprt, struct rpcrdma_write_array *wr_ary, struct rpcrdma_msg *rdma_resp, struct svc_rqst *rqstp, struct svc_rdma_req_map *vec) { u32 xfer_len = rqstp->rq_res.page_len; int write_len; u32 xdr_off; int chunk_off; int chunk_no; int nchunks; struct rpcrdma_write_array *res_ary; int ret; res_ary = (struct rpcrdma_write_array *) &rdma_resp->rm_body.rm_chunks[1]; /* Write chunks start at the pagelist */ nchunks = be32_to_cpu(wr_ary->wc_nchunks); for (xdr_off = rqstp->rq_res.head[0].iov_len, chunk_no = 0; xfer_len && chunk_no < nchunks; chunk_no++) { struct rpcrdma_segment *arg_ch; u64 rs_offset; arg_ch = &wr_ary->wc_array[chunk_no].wc_target; write_len = min(xfer_len, be32_to_cpu(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, be32_to_cpu(arg_ch->rs_handle), rs_offset + chunk_off, xdr_off, write_len, vec); if (ret <= 0) goto out_err; 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; out_err: pr_err("svcrdma: failed to send write chunks, rc=%d\n", ret); return -EIO; } noinline static int send_reply_chunks(struct svcxprt_rdma *xprt, struct rpcrdma_write_array *rp_ary, 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 *res_ary; int ret; /* 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 = be32_to_cpu(rp_ary->wc_nchunks); for (xdr_off = 0, chunk_no = 0; xfer_len && chunk_no < nchunks; chunk_no++) { u64 rs_offset; ch = &rp_ary->wc_array[chunk_no].wc_target; write_len = min(xfer_len, be32_to_cpu(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, be32_to_cpu(ch->rs_handle), rs_offset + chunk_off, xdr_off, write_len, vec); if (ret <= 0) goto out_err; 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; out_err: pr_err("svcrdma: failed to send reply chunks, rc=%d\n", ret); return -EIO; } /* 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_req_map *vec, int byte_count, u32 inv_rkey) { struct svc_rdma_op_ctxt *ctxt; struct ib_send_wr send_wr; u32 xdr_off; int sge_no; int sge_bytes; int page_no; int pages; int ret = -EIO; /* Prepare the context */ ctxt = svc_rdma_get_context(rdma); ctxt->direction = DMA_TO_DEVICE; ctxt->pages[0] = page; ctxt->count = 1; /* Prepare the SGE for the RPCRDMA Header */ ctxt->sge[0].lkey = rdma->sc_pd->local_dma_lkey; ctxt->sge[0].length = svc_rdma_xdr_get_reply_hdr_len((__be32 *)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; svc_rdma_count_mappings(rdma, ctxt); ctxt->direction = DMA_TO_DEVICE; /* Map the payload indicated by 'byte_count' */ xdr_off = 0; for (sge_no = 1; byte_count && sge_no < vec->count; sge_no++) { 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; svc_rdma_count_mappings(rdma, ctxt); ctxt->sge[sge_no].lkey = rdma->sc_pd->local_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; } 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->cqe.done = svc_rdma_wc_send; send_wr.wr_cqe = &ctxt->cqe; send_wr.sg_list = ctxt->sge; send_wr.num_sge = sge_no; if (inv_rkey) { send_wr.opcode = IB_WR_SEND_WITH_INV; send_wr.ex.invalidate_rkey = inv_rkey; } else 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 ret; } 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 *wr_ary, *rp_ary; enum rpcrdma_proc reply_type; int ret; int inline_bytes; struct page *res_page; struct svc_rdma_req_map *vec; u32 inv_rkey; 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]); svc_rdma_get_write_arrays(rdma_argp, &wr_ary, &rp_ary); inv_rkey = 0; if (rdma->sc_snd_w_inv) inv_rkey = svc_rdma_get_inv_rkey(rdma_argp, wr_ary, rp_ary); /* Build an req vec for the XDR */ vec = svc_rdma_get_req_map(rdma); ret = svc_rdma_map_xdr(rdma, &rqstp->rq_res, vec, wr_ary != NULL); if (ret) goto err0; inline_bytes = rqstp->rq_res.len; /* Create the RDMA response header. xprt->xpt_mutex, * acquired in svc_send(), serializes RPC replies. The * code path below that inserts the credit grant value * into each transport header runs only inside this * critical section. */ ret = -ENOMEM; res_page = alloc_page(GFP_KERNEL); if (!res_page) goto err0; rdma_resp = page_address(res_page); if (rp_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 */ if (wr_ary) { ret = send_write_chunks(rdma, wr_ary, rdma_resp, rqstp, vec); if (ret < 0) goto err1; inline_bytes -= ret + xdr_padsize(ret); } /* Send any reply-list data and update resp reply-list */ if (rp_ary) { ret = send_reply_chunks(rdma, rp_ary, rdma_resp, rqstp, vec); if (ret < 0) goto err1; inline_bytes -= ret; } /* Post a fresh Receive buffer _before_ sending the reply */ ret = svc_rdma_post_recv(rdma, GFP_KERNEL); if (ret) goto err1; ret = send_reply(rdma, rqstp, res_page, rdma_resp, vec, inline_bytes, inv_rkey); if (ret < 0) goto err0; svc_rdma_put_req_map(rdma, vec); dprintk("svcrdma: send_reply returns %d\n", ret); return ret; err1: put_page(res_page); err0: svc_rdma_put_req_map(rdma, vec); pr_err("svcrdma: Could not send reply, err=%d. Closing transport.\n", ret); set_bit(XPT_CLOSE, &rdma->sc_xprt.xpt_flags); return -ENOTCONN; } void svc_rdma_send_error(struct svcxprt_rdma *xprt, struct rpcrdma_msg *rmsgp, int status) { struct ib_send_wr err_wr; struct page *p; struct svc_rdma_op_ctxt *ctxt; enum rpcrdma_errcode err; __be32 *va; int length; int ret; ret = svc_rdma_repost_recv(xprt, GFP_KERNEL); if (ret) return; p = alloc_page(GFP_KERNEL); if (!p) return; va = page_address(p); /* XDR encode an error reply */ err = ERR_CHUNK; if (status == -EPROTONOSUPPORT) err = ERR_VERS; length = svc_rdma_xdr_encode_error(xprt, rmsgp, err, va); ctxt = svc_rdma_get_context(xprt); ctxt->direction = DMA_TO_DEVICE; ctxt->count = 1; ctxt->pages[0] = p; /* Prepare SGE for local address */ ctxt->sge[0].lkey = xprt->sc_pd->local_dma_lkey; ctxt->sge[0].length = length; ctxt->sge[0].addr = ib_dma_map_page(xprt->sc_cm_id->device, p, 0, length, DMA_TO_DEVICE); if (ib_dma_mapping_error(xprt->sc_cm_id->device, ctxt->sge[0].addr)) { dprintk("svcrdma: Error mapping buffer for protocol error\n"); svc_rdma_put_context(ctxt, 1); return; } svc_rdma_count_mappings(xprt, ctxt); /* Prepare SEND WR */ memset(&err_wr, 0, sizeof(err_wr)); ctxt->cqe.done = svc_rdma_wc_send; err_wr.wr_cqe = &ctxt->cqe; err_wr.sg_list = ctxt->sge; err_wr.num_sge = 1; err_wr.opcode = IB_WR_SEND; err_wr.send_flags = IB_SEND_SIGNALED; /* Post It */ ret = svc_rdma_send(xprt, &err_wr); if (ret) { dprintk("svcrdma: Error %d posting send for protocol error\n", ret); svc_rdma_unmap_dma(ctxt); svc_rdma_put_context(ctxt, 1); } }