From 8a053433de00380a9c5758d94c7c2ec2e25321fe Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Mon, 19 Apr 2021 14:03:19 -0400 Subject: [PATCH] xprtrdma: Do not wake RPC consumer on a failed LocalInv Throw away any reply where the LocalInv flushes or could not be posted. The registered memory region is in an unknown state until the disconnect completes. rpcrdma_xprt_disconnect() will find and release the MR. No need to put it back on the MR free list in this case. The client retransmits pending RPC requests once it reestablishes a fresh connection, so a replacement reply should be forthcoming on the next connection instance. Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust --- net/sunrpc/xprtrdma/frwr_ops.c | 17 +++++++++++------ net/sunrpc/xprtrdma/rpc_rdma.c | 32 +++++++++++++++++++++++++++++--- net/sunrpc/xprtrdma/xprt_rdma.h | 1 + 3 files changed, 41 insertions(+), 9 deletions(-) diff --git a/net/sunrpc/xprtrdma/frwr_ops.c b/net/sunrpc/xprtrdma/frwr_ops.c index 27087dc8ba3c..951ae20485f3 100644 --- a/net/sunrpc/xprtrdma/frwr_ops.c +++ b/net/sunrpc/xprtrdma/frwr_ops.c @@ -576,10 +576,14 @@ static void frwr_wc_localinv_done(struct ib_cq *cq, struct ib_wc *wc) rep = mr->mr_req->rl_reply; smp_rmb(); - frwr_mr_done(wc, mr); + if (wc->status != IB_WC_SUCCESS) { + if (rep) + rpcrdma_unpin_rqst(rep); + rpcrdma_flush_disconnect(cq->cq_context, wc); + return; + } + frwr_mr_put(mr); rpcrdma_complete_rqst(rep); - - rpcrdma_flush_disconnect(cq->cq_context, wc); } /** @@ -645,8 +649,9 @@ void frwr_unmap_async(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req) trace_xprtrdma_post_linv_err(req, rc); /* The final LOCAL_INV WR in the chain is supposed to - * do the wake. If it was never posted, the wake will - * not happen, so wake here in that case. + * do the wake. If it was never posted, the wake does + * not happen. Unpin the rqst in preparation for its + * retransmission. */ - rpcrdma_complete_rqst(req->rl_reply); + rpcrdma_unpin_rqst(req->rl_reply); } diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c index be4e888e78a3..649f7d8b9733 100644 --- a/net/sunrpc/xprtrdma/rpc_rdma.c +++ b/net/sunrpc/xprtrdma/rpc_rdma.c @@ -1326,9 +1326,35 @@ rpcrdma_decode_error(struct rpcrdma_xprt *r_xprt, struct rpcrdma_rep *rep, return -EIO; } -/* Perform XID lookup, reconstruction of the RPC reply, and - * RPC completion while holding the transport lock to ensure - * the rep, rqst, and rq_task pointers remain stable. +/** + * rpcrdma_unpin_rqst - Release rqst without completing it + * @rep: RPC/RDMA Receive context + * + * This is done when a connection is lost so that a Reply + * can be dropped and its matching Call can be subsequently + * retransmitted on a new connection. + */ +void rpcrdma_unpin_rqst(struct rpcrdma_rep *rep) +{ + struct rpc_xprt *xprt = &rep->rr_rxprt->rx_xprt; + struct rpc_rqst *rqst = rep->rr_rqst; + struct rpcrdma_req *req = rpcr_to_rdmar(rqst); + + req->rl_reply = NULL; + rep->rr_rqst = NULL; + + spin_lock(&xprt->queue_lock); + xprt_unpin_rqst(rqst); + spin_unlock(&xprt->queue_lock); +} + +/** + * rpcrdma_complete_rqst - Pass completed rqst back to RPC + * @rep: RPC/RDMA Receive context + * + * Reconstruct the RPC reply and complete the transaction + * while @rqst is still pinned to ensure the rep, rqst, and + * rq_task pointers remain stable. */ void rpcrdma_complete_rqst(struct rpcrdma_rep *rep) { diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h index 1b187d1dee8a..bb8aba390b88 100644 --- a/net/sunrpc/xprtrdma/xprt_rdma.h +++ b/net/sunrpc/xprtrdma/xprt_rdma.h @@ -561,6 +561,7 @@ int rpcrdma_marshal_req(struct rpcrdma_xprt *r_xprt, struct rpc_rqst *rqst); void rpcrdma_set_max_header_sizes(struct rpcrdma_ep *ep); void rpcrdma_reset_cwnd(struct rpcrdma_xprt *r_xprt); void rpcrdma_complete_rqst(struct rpcrdma_rep *rep); +void rpcrdma_unpin_rqst(struct rpcrdma_rep *rep); void rpcrdma_reply_handler(struct rpcrdma_rep *rep); static inline void rpcrdma_set_xdrlen(struct xdr_buf *xdr, size_t len) -- 2.20.1