From patchwork Mon Nov 20 11:30:59 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sagi Grimberg X-Patchwork-Id: 10066333 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 9A7F4602B7 for ; Mon, 20 Nov 2017 11:31:15 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8915429053 for ; Mon, 20 Nov 2017 11:31:15 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7BAC329057; Mon, 20 Nov 2017 11:31:15 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1BE2C29277 for ; Mon, 20 Nov 2017 11:31:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751071AbdKTLbN (ORCPT ); Mon, 20 Nov 2017 06:31:13 -0500 Received: from merlin.infradead.org ([205.233.59.134]:46088 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751070AbdKTLbN (ORCPT ); Mon, 20 Nov 2017 06:31:13 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=References:In-Reply-To:Message-Id:Date: Subject:Cc:To:From:Sender:Reply-To:MIME-Version:Content-Type: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=BitePckFCKp378kApk3Pkfscv+QbmhczDgrdttvWy3Q=; b=sUPRuaRF2jeo24LNz3goNWUar fhdwsA8lIihFt2CBujaMcd8S2mQ1cqufGvcAHdNZ1STGBncsT2hJxamXHAYIBjL1Vt2ppnfqOJwy1 2t2prNpz2yfvQ555W8b3WQUo9hnH7QeH9FYHszrObfAQXMUM1BXwF6eklMk3tn3njXkSsdav8prrc w7n+JrZQewamVWmMlrQhvDME3wiOTfO6NsbmHQglkbNYQ6ByS9aumUAr4qU+GxGc2KsQKKllfaYtf UJHdXfD1SRKUEkrfOSN1OlEw/zWnfXbFJCImOwu8/ApyYuBGBPY2gsNlA8S4CtO5gQ6gehxYv8RvC bqKEpI4jA==; Received: from bzq-82-81-101-184.red.bezeqint.net ([82.81.101.184] helo=bombadil.infradead.org) by merlin.infradead.org with esmtpsa (Exim 4.87 #1 (Red Hat Linux)) id 1eGkIC-0004cm-EJ; Mon, 20 Nov 2017 11:31:12 +0000 From: Sagi Grimberg To: linux-nvme@lists.infradead.org, linux-rdma@vger.kernel.org Cc: Christoph Hellwig Subject: [PATCH v4 2/4] nvme-rdma: don't complete requests before a send work request has completed Date: Mon, 20 Nov 2017 13:30:59 +0200 Message-Id: <20171120113101.8292-3-sagi@grimberg.me> X-Mailer: git-send-email 2.14.1 In-Reply-To: <20171120113101.8292-1-sagi@grimberg.me> References: <20171120113101.8292-1-sagi@grimberg.me> Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP In order to guarantee that the HCA will never get an access violation (either from invalidated rkey or from iommu) when retrying a send operation we must complete a request only when both send completion and the nvme cqe has arrived. We need to set the send/recv completions flags atomically because we might have more than a single context accessing the request concurrently (one is cq irq-poll context and the other is user-polling used in IOCB_HIPRI). Only then we are safe to invalidate the rkey (if needed), unmap the host buffers, and complete the IO. Signed-off-by: Sagi Grimberg --- drivers/nvme/host/rdma.c | 28 ++++++++++++++++++++++++---- 1 file changed, 24 insertions(+), 4 deletions(-) diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c index 85c98589a5e0..9202cfa9300b 100644 --- a/drivers/nvme/host/rdma.c +++ b/drivers/nvme/host/rdma.c @@ -59,6 +59,9 @@ struct nvme_rdma_request { struct nvme_request req; struct ib_mr *mr; struct nvme_rdma_qe sqe; + union nvme_result result; + __le16 status; + refcount_t ref; struct ib_sge sge[1 + NVME_RDMA_MAX_INLINE_SEGMENTS]; u32 num_sge; int nents; @@ -1162,6 +1165,7 @@ static int nvme_rdma_map_data(struct nvme_rdma_queue *queue, req->num_sge = 1; req->inline_data = false; req->mr->need_inval = false; + refcount_set(&req->ref, 2); /* send and recv completions */ c->common.flags |= NVME_CMD_SGL_METABUF; @@ -1198,8 +1202,19 @@ static int nvme_rdma_map_data(struct nvme_rdma_queue *queue, static void nvme_rdma_send_done(struct ib_cq *cq, struct ib_wc *wc) { - if (unlikely(wc->status != IB_WC_SUCCESS)) + struct nvme_rdma_qe *qe = + container_of(wc->wr_cqe, struct nvme_rdma_qe, cqe); + struct nvme_rdma_request *req = + container_of(qe, struct nvme_rdma_request, sqe); + struct request *rq = blk_mq_rq_from_pdu(req); + + if (unlikely(wc->status != IB_WC_SUCCESS)) { nvme_rdma_wr_error(cq, wc, "SEND"); + return; + } + + if (refcount_dec_and_test(&req->ref)) + nvme_end_request(rq, req->status, req->result); } static int nvme_rdma_post_send(struct nvme_rdma_queue *queue, @@ -1318,14 +1333,19 @@ static int nvme_rdma_process_nvme_rsp(struct nvme_rdma_queue *queue, } req = blk_mq_rq_to_pdu(rq); - if (rq->tag == tag) - ret = 1; + req->status = cqe->status; + req->result = cqe->result; if ((wc->wc_flags & IB_WC_WITH_INVALIDATE) && wc->ex.invalidate_rkey == req->mr->rkey) req->mr->need_inval = false; - nvme_end_request(rq, cqe->status, cqe->result); + if (refcount_dec_and_test(&req->ref)) { + if (rq->tag == tag) + ret = 1; + nvme_end_request(rq, req->status, req->result); + } + return ret; }