Return-Path: Received: from mail-io0-f196.google.com ([209.85.223.196]:35596 "EHLO mail-io0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756793AbcBCPwE (ORCPT ); Wed, 3 Feb 2016 10:52:04 -0500 Subject: [PATCH v1 05/10] svcrdma: Make RDMA_ERROR messages work From: Chuck Lever To: linux-rdma@vger.kernel.org, linux-nfs@vger.kernel.org Date: Wed, 03 Feb 2016 10:52:03 -0500 Message-ID: <20160203155203.13868.93909.stgit@klimt.1015granger.net> In-Reply-To: <20160203154411.13868.48268.stgit@klimt.1015granger.net> References: <20160203154411.13868.48268.stgit@klimt.1015granger.net> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: Fix several issues with svc_rdma_send_error(): - Post a receive buffer to replace the one that was consumed by the incoming request - Posting a send should use DMA_TO_DEVICE, not DMA_FROM_DEVICE - No need to put_page _and_ free pages in svc_rdma_put_context - Make sure the sge is set up completely in case the error path goes through svc_rdma_unmap_dma() Related fixes in svc_rdma_recvfrom(): - Don't leak the ctxt associated with the incoming request - Don't close the connection after sending an error reply - Let svc_rdma_send_error() figure out the right header error code As a last clean up, move svc_rdma_send_error() to svc_rdma_sendto.c with other similar functions. There is some common logic in these functions that could someday be combined to reduce code duplication. Signed-off-by: Chuck Lever --- include/linux/sunrpc/svc_rdma.h | 4 +- net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 19 ++++----- net/sunrpc/xprtrdma/svc_rdma_sendto.c | 62 ++++++++++++++++++++++++++++++ net/sunrpc/xprtrdma/svc_rdma_transport.c | 54 -------------------------- 4 files changed, 73 insertions(+), 66 deletions(-) diff --git a/include/linux/sunrpc/svc_rdma.h b/include/linux/sunrpc/svc_rdma.h index d8fc58d..0589918 100644 --- a/include/linux/sunrpc/svc_rdma.h +++ b/include/linux/sunrpc/svc_rdma.h @@ -228,11 +228,11 @@ extern int svc_rdma_map_xdr(struct svcxprt_rdma *, struct xdr_buf *, extern int svc_rdma_sendto(struct svc_rqst *); extern struct rpcrdma_read_chunk * svc_rdma_get_read_chunk(struct rpcrdma_msg *); +extern void svc_rdma_send_error(struct svcxprt_rdma *, struct rpcrdma_msg *, + int); /* svc_rdma_transport.c */ extern int svc_rdma_send(struct svcxprt_rdma *, struct ib_send_wr *); -extern void svc_rdma_send_error(struct svcxprt_rdma *, struct rpcrdma_msg *, - enum rpcrdma_errcode); extern int svc_rdma_post_recv(struct svcxprt_rdma *, gfp_t); extern int svc_rdma_repost_recv(struct svcxprt_rdma *, gfp_t); extern int svc_rdma_create_listen(struct svc_serv *, int, struct sockaddr *); diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c index acf15b8..0f09052 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c +++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c @@ -612,7 +612,6 @@ int svc_rdma_recvfrom(struct svc_rqst *rqstp) struct svc_rdma_op_ctxt *ctxt = NULL; struct rpcrdma_msg *rmsgp; int ret = 0; - int len; dprintk("svcrdma: rqstp=%p\n", rqstp); @@ -654,15 +653,10 @@ int svc_rdma_recvfrom(struct svc_rqst *rqstp) rdma_build_arg_xdr(rqstp, ctxt, ctxt->byte_len); /* Decode the RDMA header. */ - len = svc_rdma_xdr_decode_req(&rmsgp, rqstp); - rqstp->rq_xprt_hlen = len; - - /* If the request is invalid, reply with an error */ - if (len < 0) { - if (len == -ENOSYS) - svc_rdma_send_error(rdma_xprt, rmsgp, ERR_VERS); - goto close_out; - } + ret = svc_rdma_xdr_decode_req(&rmsgp, rqstp); + if (ret < 0) + goto out_err; + rqstp->rq_xprt_hlen = ret; if (svc_rdma_is_backchannel_reply(xprt, rmsgp)) { ret = svc_rdma_handle_bc_reply(xprt->xpt_bc_xprt, rmsgp, @@ -698,6 +692,11 @@ int svc_rdma_recvfrom(struct svc_rqst *rqstp) svc_xprt_copy_addrs(rqstp, xprt); return ret; +out_err: + svc_rdma_send_error(rdma_xprt, rmsgp, ret); + svc_rdma_put_context(ctxt, 0); + return 0; + close_out: if (ctxt) svc_rdma_put_context(ctxt, 1); diff --git a/net/sunrpc/xprtrdma/svc_rdma_sendto.c b/net/sunrpc/xprtrdma/svc_rdma_sendto.c index 687a91afe..73793dd 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_sendto.c +++ b/net/sunrpc/xprtrdma/svc_rdma_sendto.c @@ -639,3 +639,65 @@ int svc_rdma_sendto(struct svc_rqst *rqstp) svc_rdma_put_context(ctxt, 0); return ret; } + +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 == -ENOSYS) + 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; + } + atomic_inc(&xprt->sc_dma_used); + + /* Prepare SEND WR */ + memset(&err_wr, 0, sizeof err_wr); + ctxt->wr_op = IB_WR_SEND; + err_wr.wr_id = (unsigned long)ctxt; + 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); + } +} diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c index da82e36..e7bda1e 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_transport.c +++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c @@ -1465,57 +1465,3 @@ int svc_rdma_send(struct svcxprt_rdma *xprt, struct ib_send_wr *wr) } return ret; } - -void svc_rdma_send_error(struct svcxprt_rdma *xprt, struct rpcrdma_msg *rmsgp, - enum rpcrdma_errcode err) -{ - struct ib_send_wr err_wr; - struct page *p; - struct svc_rdma_op_ctxt *ctxt; - __be32 *va; - int length; - int ret; - - p = alloc_page(GFP_KERNEL); - if (!p) - return; - va = page_address(p); - - /* XDR encode error */ - length = svc_rdma_xdr_encode_error(xprt, rmsgp, err, va); - - ctxt = svc_rdma_get_context(xprt); - ctxt->direction = DMA_FROM_DEVICE; - ctxt->count = 1; - ctxt->pages[0] = p; - - /* Prepare SGE for local address */ - ctxt->sge[0].addr = ib_dma_map_page(xprt->sc_cm_id->device, - p, 0, length, DMA_FROM_DEVICE); - if (ib_dma_mapping_error(xprt->sc_cm_id->device, ctxt->sge[0].addr)) { - put_page(p); - svc_rdma_put_context(ctxt, 1); - return; - } - atomic_inc(&xprt->sc_dma_used); - ctxt->sge[0].lkey = xprt->sc_pd->local_dma_lkey; - ctxt->sge[0].length = length; - - /* Prepare SEND WR */ - memset(&err_wr, 0, sizeof err_wr); - ctxt->wr_op = IB_WR_SEND; - err_wr.wr_id = (unsigned long)ctxt; - 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); - } -}