diff options
Diffstat (limited to 'net/sunrpc/xprtrdma/backchannel.c')
| -rw-r--r-- | net/sunrpc/xprtrdma/backchannel.c | 71 |
1 files changed, 27 insertions, 44 deletions
diff --git a/net/sunrpc/xprtrdma/backchannel.c b/net/sunrpc/xprtrdma/backchannel.c index 03f6b5840764..d31d0ac5ada9 100644 --- a/net/sunrpc/xprtrdma/backchannel.c +++ b/net/sunrpc/xprtrdma/backchannel.c @@ -49,6 +49,7 @@ static int rpcrdma_bc_setup_rqst(struct rpcrdma_xprt *r_xprt, if (IS_ERR(rb)) goto out_fail; req->rl_rdmabuf = rb; + xdr_buf_init(&req->rl_hdrbuf, rb->rg_base, rdmab_length(rb)); size = r_xprt->rx_data.inline_rsize; rb = rpcrdma_alloc_regbuf(size, DMA_TO_DEVICE, GFP_KERNEL); @@ -202,20 +203,24 @@ size_t xprt_rdma_bc_maxpayload(struct rpc_xprt *xprt) */ int rpcrdma_bc_marshal_reply(struct rpc_rqst *rqst) { - struct rpc_xprt *xprt = rqst->rq_xprt; - struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt); + struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(rqst->rq_xprt); struct rpcrdma_req *req = rpcr_to_rdmar(rqst); - struct rpcrdma_msg *headerp; - - headerp = rdmab_to_msg(req->rl_rdmabuf); - headerp->rm_xid = rqst->rq_xid; - headerp->rm_vers = rpcrdma_version; - headerp->rm_credit = - cpu_to_be32(r_xprt->rx_buf.rb_bc_srv_max_requests); - headerp->rm_type = rdma_msg; - headerp->rm_body.rm_chunks[0] = xdr_zero; - headerp->rm_body.rm_chunks[1] = xdr_zero; - headerp->rm_body.rm_chunks[2] = xdr_zero; + __be32 *p; + + rpcrdma_set_xdrlen(&req->rl_hdrbuf, 0); + xdr_init_encode(&req->rl_stream, &req->rl_hdrbuf, + req->rl_rdmabuf->rg_base); + + p = xdr_reserve_space(&req->rl_stream, 28); + if (unlikely(!p)) + return -EIO; + *p++ = rqst->rq_xid; + *p++ = rpcrdma_version; + *p++ = cpu_to_be32(r_xprt->rx_buf.rb_bc_srv_max_requests); + *p++ = rdma_msg; + *p++ = xdr_zero; + *p++ = xdr_zero; + *p = xdr_zero; if (!rpcrdma_prepare_send_sges(&r_xprt->rx_ia, req, RPCRDMA_HDRLEN_MIN, &rqst->rq_snd_buf, rpcrdma_noch)) @@ -271,9 +276,6 @@ void xprt_rdma_bc_free_rqst(struct rpc_rqst *rqst) * @xprt: transport receiving the call * @rep: receive buffer containing the call * - * Called in the RPC reply handler, which runs in a tasklet. - * Be quick about it. - * * Operational assumptions: * o Backchannel credits are ignored, just as the NFS server * forechannel currently does @@ -284,7 +286,6 @@ void rpcrdma_bc_receive_call(struct rpcrdma_xprt *r_xprt, struct rpcrdma_rep *rep) { struct rpc_xprt *xprt = &r_xprt->rx_xprt; - struct rpcrdma_msg *headerp; struct svc_serv *bc_serv; struct rpcrdma_req *req; struct rpc_rqst *rqst; @@ -292,24 +293,15 @@ void rpcrdma_bc_receive_call(struct rpcrdma_xprt *r_xprt, size_t size; __be32 *p; - headerp = rdmab_to_msg(rep->rr_rdmabuf); + p = xdr_inline_decode(&rep->rr_stream, 0); + size = xdr_stream_remaining(&rep->rr_stream); + #ifdef RPCRDMA_BACKCHANNEL_DEBUG pr_info("RPC: %s: callback XID %08x, length=%u\n", - __func__, be32_to_cpu(headerp->rm_xid), rep->rr_len); - pr_info("RPC: %s: %*ph\n", __func__, rep->rr_len, headerp); + __func__, be32_to_cpup(p), size); + pr_info("RPC: %s: %*ph\n", __func__, size, p); #endif - /* Sanity check: - * Need at least enough bytes for RPC/RDMA header, as code - * here references the header fields by array offset. Also, - * backward calls are always inline, so ensure there - * are some bytes beyond the RPC/RDMA header. - */ - if (rep->rr_len < RPCRDMA_HDRLEN_MIN + 24) - goto out_short; - p = (__be32 *)((unsigned char *)headerp + RPCRDMA_HDRLEN_MIN); - size = rep->rr_len - RPCRDMA_HDRLEN_MIN; - /* Grab a free bc rqst */ spin_lock(&xprt->bc_pa_lock); if (list_empty(&xprt->bc_pa_list)) { @@ -325,7 +317,7 @@ void rpcrdma_bc_receive_call(struct rpcrdma_xprt *r_xprt, /* Prepare rqst */ rqst->rq_reply_bytes_recvd = 0; rqst->rq_bytes_sent = 0; - rqst->rq_xid = headerp->rm_xid; + rqst->rq_xid = *p; rqst->rq_private_buf.len = size; set_bit(RPC_BC_PA_IN_USE, &rqst->rq_bc_pa_state); @@ -337,9 +329,9 @@ void rpcrdma_bc_receive_call(struct rpcrdma_xprt *r_xprt, buf->len = size; /* The receive buffer has to be hooked to the rpcrdma_req - * so that it can be reposted after the server is done - * parsing it but just before sending the backward - * direction reply. + * so that it is not released while the req is pointing + * to its buffer, and so that it can be reposted after + * the Upper Layer is done decoding it. */ req = rpcr_to_rdmar(rqst); dprintk("RPC: %s: attaching rep %p to req %p\n", @@ -367,13 +359,4 @@ out_overflow: * when the connection is re-established. */ return; - -out_short: - pr_warn("RPC/RDMA short backward direction call\n"); - - if (rpcrdma_ep_post_recv(&r_xprt->rx_ia, rep)) - xprt_disconnect_done(xprt); - else - pr_warn("RPC: %s: reposting rep %p\n", - __func__, rep); } |