Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-ig0-f173.google.com ([209.85.213.173]:56090 "EHLO mail-ig0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755089AbaGVOvS (ORCPT ); Tue, 22 Jul 2014 10:51:18 -0400 Subject: [PATCH v4 02/21] xprtrdma: Protect ia->ri_id when unmapping/invalidating MRs From: Chuck Lever To: Anna.Schumaker@netapp.com Cc: linux-rdma@vger.kernel.org, linux-nfs@vger.kernel.org Date: Tue, 22 Jul 2014 10:51:16 -0400 Message-ID: <20140722145116.6010.56308.stgit@manet.1015granger.net> In-Reply-To: <20140722144459.6010.99389.stgit@manet.1015granger.net> References: <20140722144459.6010.99389.stgit@manet.1015granger.net> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: Ensure ia->ri_id remains valid while invoking dma_unmap_page() or posting LOCAL_INV during a transport reconnect. Otherwise, ia->ri_id->device or ia->ri_id->qp is NULL, which triggers a panic. BugLink: https://bugzilla.linux-nfs.org/show_bug.cgi?id=259 Fixes: ec62f40 'xprtrdma: Ensure ia->ri_id->qp is not NULL when reconnecting' Signed-off-by: Chuck Lever Tested-by: Steve Wise Tested-by: Shirley Ma Tested-by: Devesh Sharma --- net/sunrpc/xprtrdma/verbs.c | 23 +++++++++++++++++------ net/sunrpc/xprtrdma/xprt_rdma.h | 1 + 2 files changed, 18 insertions(+), 6 deletions(-) diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c index 78bd7c6..cab742d 100644 --- a/net/sunrpc/xprtrdma/verbs.c +++ b/net/sunrpc/xprtrdma/verbs.c @@ -613,6 +613,7 @@ rpcrdma_ia_open(struct rpcrdma_xprt *xprt, struct sockaddr *addr, int memreg) /* Else will do memory reg/dereg for each chunk */ ia->ri_memreg_strategy = memreg; + rwlock_init(&ia->ri_qplock); return 0; out2: rdma_destroy_id(ia->ri_id); @@ -859,7 +860,7 @@ rpcrdma_ep_destroy(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia) int rpcrdma_ep_connect(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia) { - struct rdma_cm_id *id; + struct rdma_cm_id *id, *old; int rc = 0; int retry_count = 0; @@ -905,9 +906,14 @@ retry: rc = -ENETUNREACH; goto out; } - rdma_destroy_qp(ia->ri_id); - rdma_destroy_id(ia->ri_id); + + write_lock(&ia->ri_qplock); + old = ia->ri_id; ia->ri_id = id; + write_unlock(&ia->ri_qplock); + + rdma_destroy_qp(old); + rdma_destroy_id(old); } else { dprintk("RPC: %s: connecting...\n", __func__); rc = rdma_create_qp(ia->ri_id, ia->ri_pd, &ep->rep_attr); @@ -1587,9 +1593,6 @@ rpcrdma_deregister_frmr_external(struct rpcrdma_mr_seg *seg, struct ib_send_wr invalidate_wr, *bad_wr; int rc; - while (seg1->mr_nsegs--) - rpcrdma_unmap_one(ia, seg++); - memset(&invalidate_wr, 0, sizeof invalidate_wr); invalidate_wr.wr_id = (unsigned long)(void *)seg1->mr_chunk.rl_mw; invalidate_wr.opcode = IB_WR_LOCAL_INV; @@ -1597,7 +1600,11 @@ rpcrdma_deregister_frmr_external(struct rpcrdma_mr_seg *seg, invalidate_wr.ex.invalidate_rkey = seg1->mr_chunk.rl_mw->r.frmr.fr_mr->rkey; DECR_CQCOUNT(&r_xprt->rx_ep); + read_lock(&ia->ri_qplock); + while (seg1->mr_nsegs--) + rpcrdma_unmap_one(ia, seg++); rc = ib_post_send(ia->ri_id->qp, &invalidate_wr, &bad_wr); + read_unlock(&ia->ri_qplock); if (rc) dprintk("RPC: %s: failed ib_post_send for invalidate," " status %i\n", __func__, rc); @@ -1658,8 +1665,10 @@ rpcrdma_deregister_fmr_external(struct rpcrdma_mr_seg *seg, list_add(&seg1->mr_chunk.rl_mw->r.fmr->list, &l); rc = ib_unmap_fmr(&l); + read_lock(&ia->ri_qplock); while (seg1->mr_nsegs--) rpcrdma_unmap_one(ia, seg++); + read_unlock(&ia->ri_qplock); if (rc) dprintk("RPC: %s: failed ib_unmap_fmr," " status %i\n", __func__, rc); @@ -1715,7 +1724,9 @@ rpcrdma_deregister_external(struct rpcrdma_mr_seg *seg, #if RPCRDMA_PERSISTENT_REGISTRATION case RPCRDMA_ALLPHYSICAL: + read_lock(&ia->ri_qplock); rpcrdma_unmap_one(ia, seg); + read_unlock(&ia->ri_qplock); break; #endif diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h index 89e7cd4..97ca516 100644 --- a/net/sunrpc/xprtrdma/xprt_rdma.h +++ b/net/sunrpc/xprtrdma/xprt_rdma.h @@ -59,6 +59,7 @@ * Interface Adapter -- one per transport instance */ struct rpcrdma_ia { + rwlock_t ri_qplock; struct rdma_cm_id *ri_id; struct ib_pd *ri_pd; struct ib_mr *ri_bind_mem;