Return-Path: Received: from smtp.opengridcomputing.com ([209.198.142.2]:35134 "EHLO smtp.opengridcomputing.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932283Ab0HCQpH (ORCPT ); Tue, 3 Aug 2010 12:45:07 -0400 From: Tom Tucker Subject: [PATCH 2/4] svcrdma: Change DMA mapping logic to avoid the page_address kernel API To: trond.myklebust@netapp.com, bfields@fieldses.org Cc: linux-nfs@vger.kernel.org, swise@ogc.us, tom@ogc.us Date: Tue, 03 Aug 2010 11:45:06 -0500 Message-ID: <20100803164506.2567.56713.stgit@build.ogc.int> In-Reply-To: <20100803164411.2567.31416.stgit@build.ogc.int> References: <20100803164411.2567.31416.stgit@build.ogc.int> Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: MIME-Version: 1.0 There was logic in the send path that assumed that a page containing data to send to the client has a KVA. This is not always the case and can result in data corruption when page_address returns zero and we end up DMA mapping zero. This patch changes the bus mapping logic to avoid page_address() where necessary and converts all calls from ib_dma_map_single to ib_dma_map_page in order to keep the map/unmap calls symmetric. Signed-off-by: Tom Tucker --- net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 18 ++++--- net/sunrpc/xprtrdma/svc_rdma_sendto.c | 80 ++++++++++++++++++++++-------- net/sunrpc/xprtrdma/svc_rdma_transport.c | 18 +++---- 3 files changed, 78 insertions(+), 38 deletions(-) diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c index 0194de8..926bdb4 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c +++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c @@ -263,9 +263,9 @@ static int fast_reg_read_chunks(struct svcxprt_rdma *xprt, frmr->page_list_len = PAGE_ALIGN(byte_count) >> PAGE_SHIFT; for (page_no = 0; page_no < frmr->page_list_len; page_no++) { frmr->page_list->page_list[page_no] = - ib_dma_map_single(xprt->sc_cm_id->device, - page_address(rqstp->rq_arg.pages[page_no]), - PAGE_SIZE, DMA_FROM_DEVICE); + ib_dma_map_page(xprt->sc_cm_id->device, + rqstp->rq_arg.pages[page_no], 0, + PAGE_SIZE, DMA_FROM_DEVICE); if (ib_dma_mapping_error(xprt->sc_cm_id->device, frmr->page_list->page_list[page_no])) goto fatal_err; @@ -309,17 +309,21 @@ static int rdma_set_ctxt_sge(struct svcxprt_rdma *xprt, int count) { int i; + unsigned long off; ctxt->count = count; ctxt->direction = DMA_FROM_DEVICE; for (i = 0; i < count; i++) { ctxt->sge[i].length = 0; /* in case map fails */ if (!frmr) { + BUG_ON(0 == virt_to_page(vec[i].iov_base)); + off = (unsigned long)vec[i].iov_base & ~PAGE_MASK; ctxt->sge[i].addr = - ib_dma_map_single(xprt->sc_cm_id->device, - vec[i].iov_base, - vec[i].iov_len, - DMA_FROM_DEVICE); + ib_dma_map_page(xprt->sc_cm_id->device, + virt_to_page(vec[i].iov_base), + off, + vec[i].iov_len, + DMA_FROM_DEVICE); if (ib_dma_mapping_error(xprt->sc_cm_id->device, ctxt->sge[i].addr)) return -EINVAL; diff --git a/net/sunrpc/xprtrdma/svc_rdma_sendto.c b/net/sunrpc/xprtrdma/svc_rdma_sendto.c index b15e1eb..d4f5e0e 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_sendto.c +++ b/net/sunrpc/xprtrdma/svc_rdma_sendto.c @@ -70,8 +70,8 @@ * on extra page for the RPCRMDA header. */ static int fast_reg_xdr(struct svcxprt_rdma *xprt, - struct xdr_buf *xdr, - struct svc_rdma_req_map *vec) + struct xdr_buf *xdr, + struct svc_rdma_req_map *vec) { int sge_no; u32 sge_bytes; @@ -96,21 +96,25 @@ static int fast_reg_xdr(struct svcxprt_rdma *xprt, vec->count = 2; sge_no++; - /* Build the FRMR */ + /* Map the XDR head */ frmr->kva = frva; frmr->direction = DMA_TO_DEVICE; frmr->access_flags = 0; frmr->map_len = PAGE_SIZE; frmr->page_list_len = 1; + page_off = (unsigned long)xdr->head[0].iov_base & ~PAGE_MASK; frmr->page_list->page_list[page_no] = - ib_dma_map_single(xprt->sc_cm_id->device, - (void *)xdr->head[0].iov_base, - PAGE_SIZE, DMA_TO_DEVICE); + ib_dma_map_page(xprt->sc_cm_id->device, + virt_to_page(xdr->head[0].iov_base), + page_off, + PAGE_SIZE - page_off, + DMA_TO_DEVICE); if (ib_dma_mapping_error(xprt->sc_cm_id->device, frmr->page_list->page_list[page_no])) goto fatal_err; atomic_inc(&xprt->sc_dma_used); + /* Map the XDR page list */ page_off = xdr->page_base; page_bytes = xdr->page_len + page_off; if (!page_bytes) @@ -128,9 +132,9 @@ static int fast_reg_xdr(struct svcxprt_rdma *xprt, page_bytes -= sge_bytes; frmr->page_list->page_list[page_no] = - ib_dma_map_single(xprt->sc_cm_id->device, - page_address(page), - PAGE_SIZE, DMA_TO_DEVICE); + ib_dma_map_page(xprt->sc_cm_id->device, + page, page_off, + sge_bytes, DMA_TO_DEVICE); if (ib_dma_mapping_error(xprt->sc_cm_id->device, frmr->page_list->page_list[page_no])) goto fatal_err; @@ -166,8 +170,10 @@ static int fast_reg_xdr(struct svcxprt_rdma *xprt, vec->sge[sge_no].iov_base = frva + frmr->map_len + page_off; frmr->page_list->page_list[page_no] = - ib_dma_map_single(xprt->sc_cm_id->device, va, PAGE_SIZE, - DMA_TO_DEVICE); + ib_dma_map_page(xprt->sc_cm_id->device, virt_to_page(va), + page_off, + PAGE_SIZE, + DMA_TO_DEVICE); if (ib_dma_mapping_error(xprt->sc_cm_id->device, frmr->page_list->page_list[page_no])) goto fatal_err; @@ -245,6 +251,35 @@ static int map_xdr(struct svcxprt_rdma *xprt, 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 */ + 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: * - We are using FRMR * - or - @@ -293,10 +328,9 @@ static int send_write(struct svcxprt_rdma *xprt, struct svc_rqst *rqstp, sge[sge_no].length = sge_bytes; if (!vec->frmr) { sge[sge_no].addr = - ib_dma_map_single(xprt->sc_cm_id->device, - (void *) - vec->sge[xdr_sge_no].iov_base + sge_off, - sge_bytes, DMA_TO_DEVICE); + 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; @@ -494,7 +528,8 @@ static int send_reply_chunks(struct svcxprt_rdma *xprt, * 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. + * 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, @@ -536,23 +571,24 @@ static int send_reply(struct svcxprt_rdma *rdma, 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_single(rdma->sc_cm_id->device, page_address(page), - ctxt->sge[0].length, DMA_TO_DEVICE); + 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; - /* Determine how many of our SGE are to be transmitted */ + /* 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; if (!vec->frmr) { ctxt->sge[sge_no].addr = - ib_dma_map_single(rdma->sc_cm_id->device, - vec->sge[sge_no].iov_base, - sge_bytes, DMA_TO_DEVICE); + 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; diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c index edea15a..23f90c3 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_transport.c +++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c @@ -120,7 +120,7 @@ void svc_rdma_unmap_dma(struct svc_rdma_op_ctxt *ctxt) */ if (ctxt->sge[i].lkey == xprt->sc_dma_lkey) { atomic_dec(&xprt->sc_dma_used); - ib_dma_unmap_single(xprt->sc_cm_id->device, + ib_dma_unmap_page(xprt->sc_cm_id->device, ctxt->sge[i].addr, ctxt->sge[i].length, ctxt->direction); @@ -502,8 +502,8 @@ int svc_rdma_post_recv(struct svcxprt_rdma *xprt) BUG_ON(sge_no >= xprt->sc_max_sge); page = svc_rdma_get_page(); ctxt->pages[sge_no] = page; - pa = ib_dma_map_single(xprt->sc_cm_id->device, - page_address(page), PAGE_SIZE, + pa = ib_dma_map_page(xprt->sc_cm_id->device, + page, 0, PAGE_SIZE, DMA_FROM_DEVICE); if (ib_dma_mapping_error(xprt->sc_cm_id->device, pa)) goto err_put_ctxt; @@ -798,8 +798,8 @@ static void frmr_unmap_dma(struct svcxprt_rdma *xprt, if (ib_dma_mapping_error(frmr->mr->device, addr)) continue; atomic_dec(&xprt->sc_dma_used); - ib_dma_unmap_single(frmr->mr->device, addr, PAGE_SIZE, - frmr->direction); + ib_dma_unmap_page(frmr->mr->device, addr, PAGE_SIZE, + frmr->direction); } } @@ -1274,7 +1274,7 @@ int svc_rdma_send(struct svcxprt_rdma *xprt, struct ib_send_wr *wr) atomic_read(&xprt->sc_sq_count) < xprt->sc_sq_depth); if (test_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags)) - return 0; + return -ENOTCONN; continue; } /* Take a transport ref for each WR posted */ @@ -1320,8 +1320,8 @@ void svc_rdma_send_error(struct svcxprt_rdma *xprt, struct rpcrdma_msg *rmsgp, length = svc_rdma_xdr_encode_error(xprt, rmsgp, err, va); /* Prepare SGE for local address */ - sge.addr = ib_dma_map_single(xprt->sc_cm_id->device, - page_address(p), PAGE_SIZE, DMA_FROM_DEVICE); + sge.addr = ib_dma_map_page(xprt->sc_cm_id->device, + p, 0, PAGE_SIZE, DMA_FROM_DEVICE); if (ib_dma_mapping_error(xprt->sc_cm_id->device, sge.addr)) { put_page(p); return; @@ -1348,7 +1348,7 @@ void svc_rdma_send_error(struct svcxprt_rdma *xprt, struct rpcrdma_msg *rmsgp, if (ret) { dprintk("svcrdma: Error %d posting send for protocol error\n", ret); - ib_dma_unmap_single(xprt->sc_cm_id->device, + ib_dma_unmap_page(xprt->sc_cm_id->device, sge.addr, PAGE_SIZE, DMA_FROM_DEVICE); svc_rdma_put_context(ctxt, 1);