Return-Path: Received: from mail-it0-f66.google.com ([209.85.214.66]:34870 "EHLO mail-it0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752154AbcHWSF4 (ORCPT ); Tue, 23 Aug 2016 14:05:56 -0400 Subject: [PATCH v2 06/22] SUNRPC: Add a transport-specific private field in rpc_rqst From: Chuck Lever To: linux-rdma@vger.kernel.org, linux-nfs@vger.kernel.org Date: Tue, 23 Aug 2016 13:52:53 -0400 Message-ID: <20160823175253.13038.61533.stgit@manet.1015granger.net> In-Reply-To: <20160823174402.13038.84561.stgit@manet.1015granger.net> References: <20160823174402.13038.84561.stgit@manet.1015granger.net> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: Currently there's a hidden and indirect mechanism for finding the rpcrdma_req that goes with an rpc_rqst. It depends on getting from the rq_buffer pointer in struct rpc_rqst to the struct rpcrdma_regbuf that controls that buffer, and then to the struct rpcrdma_req it goes with. This was done back in the day to avoid the need to add a per-rqst pointer or to alter the buf_free API when support for RPC-over-RDMA was introduced. I'm about to change the way regbuf's work to support larger inline thresholds. Now is a good time to replace this indirect mechanism with something that is more straightforward. I guess this should be considered a clean up. Signed-off-by: Chuck Lever --- include/linux/sunrpc/xprt.h | 1 + net/sunrpc/xprtrdma/backchannel.c | 6 ++---- net/sunrpc/xprtrdma/transport.c | 2 +- net/sunrpc/xprtrdma/verbs.c | 1 - net/sunrpc/xprtrdma/xprt_rdma.h | 13 +++++++------ 5 files changed, 11 insertions(+), 12 deletions(-) diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h index 46f069e..a5da60b 100644 --- a/include/linux/sunrpc/xprt.h +++ b/include/linux/sunrpc/xprt.h @@ -83,6 +83,7 @@ struct rpc_rqst { void (*rq_release_snd_buf)(struct rpc_rqst *); /* release rq_enc_pages */ struct list_head rq_list; + void *rq_xprtdata; /* Per-xprt private data */ void *rq_buffer; /* Call XDR encode buffer */ size_t rq_callsize; void *rq_rbuffer; /* Reply XDR decode buffer */ diff --git a/net/sunrpc/xprtrdma/backchannel.c b/net/sunrpc/xprtrdma/backchannel.c index d3cfaf2..c4904f8 100644 --- a/net/sunrpc/xprtrdma/backchannel.c +++ b/net/sunrpc/xprtrdma/backchannel.c @@ -55,11 +55,9 @@ static int rpcrdma_bc_setup_rqst(struct rpcrdma_xprt *r_xprt, rb = rpcrdma_alloc_regbuf(ia, size, GFP_KERNEL); if (IS_ERR(rb)) goto out_fail; - rb->rg_owner = req; req->rl_sendbuf = rb; - /* so that rpcr_to_rdmar works when receiving a request */ - rqst->rq_buffer = (void *)req->rl_sendbuf->rg_base; - xdr_buf_init(&rqst->rq_snd_buf, rqst->rq_buffer, size); + xdr_buf_init(&rqst->rq_snd_buf, rb->rg_base, size); + rpcrdma_set_xprtdata(rqst, req); return 0; out_fail: diff --git a/net/sunrpc/xprtrdma/transport.c b/net/sunrpc/xprtrdma/transport.c index 136caf3..d83bffa 100644 --- a/net/sunrpc/xprtrdma/transport.c +++ b/net/sunrpc/xprtrdma/transport.c @@ -523,6 +523,7 @@ xprt_rdma_allocate(struct rpc_task *task) out: dprintk("RPC: %s: size %zd, request 0x%p\n", __func__, size, req); req->rl_connect_cookie = 0; /* our reserved value */ + rpcrdma_set_xprtdata(rqst, req); rqst->rq_buffer = req->rl_sendbuf->rg_base; rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_rcvsize; return 0; @@ -559,7 +560,6 @@ out_sendbuf: rb = rpcrdma_alloc_regbuf(&r_xprt->rx_ia, size, flags); if (IS_ERR(rb)) goto out_fail; - rb->rg_owner = req; r_xprt->rx_stats.hardway_register_count += size; rpcrdma_free_regbuf(&r_xprt->rx_ia, req->rl_sendbuf); diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c index 536d0be..baf7f43 100644 --- a/net/sunrpc/xprtrdma/verbs.c +++ b/net/sunrpc/xprtrdma/verbs.c @@ -1191,7 +1191,6 @@ rpcrdma_alloc_regbuf(struct rpcrdma_ia *ia, size_t size, gfp_t flags) iov->length = size; iov->lkey = ia->ri_pd->local_dma_lkey; rb->rg_size = size; - rb->rg_owner = NULL; return rb; out_free: diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h index 296d9ab..99b6839 100644 --- a/net/sunrpc/xprtrdma/xprt_rdma.h +++ b/net/sunrpc/xprtrdma/xprt_rdma.h @@ -113,7 +113,6 @@ struct rpcrdma_ep { struct rpcrdma_regbuf { size_t rg_size; - struct rpcrdma_req *rg_owner; struct ib_sge rg_iov; __be32 rg_base[0] __attribute__ ((aligned(256))); }; @@ -297,14 +296,16 @@ struct rpcrdma_req { struct rpcrdma_mr_seg rl_segments[RPCRDMA_MAX_SEGS]; }; +static inline void +rpcrdma_set_xprtdata(struct rpc_rqst *rqst, struct rpcrdma_req *req) +{ + rqst->rq_xprtdata = req; +} + static inline struct rpcrdma_req * rpcr_to_rdmar(struct rpc_rqst *rqst) { - void *buffer = rqst->rq_buffer; - struct rpcrdma_regbuf *rb; - - rb = container_of(buffer, struct rpcrdma_regbuf, rg_base); - return rb->rg_owner; + return rqst->rq_xprtdata; } /*