Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754798AbbKMNyZ (ORCPT ); Fri, 13 Nov 2015 08:54:25 -0500 Received: from bombadil.infradead.org ([198.137.202.9]:51863 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754589AbbKMNvZ (ORCPT ); Fri, 13 Nov 2015 08:51:25 -0500 From: Christoph Hellwig To: linux-rdma@vger.kernel.org Cc: sagig@dev.mellanox.co.il, bart.vanassche@sandisk.com, axboe@fb.com, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 3/9] IB: add a helper to safely drain a QP Date: Fri, 13 Nov 2015 14:46:44 +0100 Message-Id: <1447422410-20891-4-git-send-email-hch@lst.de> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1447422410-20891-1-git-send-email-hch@lst.de> References: <1447422410-20891-1-git-send-email-hch@lst.de> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2170 Lines: 79 Signed-off-by: Christoph Hellwig --- drivers/infiniband/core/cq.c | 46 ++++++++++++++++++++++++++++++++++++++++++++ include/rdma/ib_verbs.h | 2 ++ 2 files changed, 48 insertions(+) diff --git a/drivers/infiniband/core/cq.c b/drivers/infiniband/core/cq.c index d9eb796..bf2a079 100644 --- a/drivers/infiniband/core/cq.c +++ b/drivers/infiniband/core/cq.c @@ -206,3 +206,49 @@ void ib_free_cq(struct ib_cq *cq) WARN_ON_ONCE(ret); } EXPORT_SYMBOL(ib_free_cq); + +struct ib_stop_cqe { + struct ib_cqe cqe; + struct completion done; +}; + +static void ib_stop_done(struct ib_cq *cq, struct ib_wc *wc) +{ + struct ib_stop_cqe *stop = + container_of(wc->wr_cqe, struct ib_stop_cqe, cqe); + + complete(&stop->done); +} + +/* + * Change a queue pair into the error state and wait until all receive + * completions have been processed before destroying it. This avoids that + * the receive completion handler can access the queue pair while it is + * being destroyed. + */ +void ib_drain_qp(struct ib_qp *qp) +{ + struct ib_qp_attr attr = { .qp_state = IB_QPS_ERR }; + struct ib_stop_cqe stop = { }; + struct ib_recv_wr wr, *bad_wr; + int ret; + + wr.wr_cqe = &stop.cqe; + stop.cqe.done = ib_stop_done; + init_completion(&stop.done); + + ret = ib_modify_qp(qp, &attr, IB_QP_STATE); + if (ret) { + WARN_ONCE(ret, "failed to drain QP: %d\n", ret); + return; + } + + ret = ib_post_recv(qp, &wr, &bad_wr); + if (ret) { + WARN_ONCE(ret, "failed to drain QP: %d\n", ret); + return; + } + + wait_for_completion(&stop.done); +} +EXPORT_SYMBOL(ib_drain_qp); diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h index e11e038..f59a8d3 100644 --- a/include/rdma/ib_verbs.h +++ b/include/rdma/ib_verbs.h @@ -3075,4 +3075,6 @@ int ib_sg_to_pages(struct ib_mr *mr, int sg_nents, int (*set_page)(struct ib_mr *, u64)); +void ib_drain_qp(struct ib_qp *qp); + #endif /* IB_VERBS_H */ -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/