// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause /* * Copyright (c) 2014-2017 Oracle. All rights reserved. * Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved. * * This software is available to you under a choice of one of two * licenses. You may choose to be licensed under the terms of the GNU * General Public License (GPL) Version 2, available from the file * COPYING in the main directory of this source tree, or the BSD-type * license below: * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials provided * with the distribution. * * Neither the name of the Network Appliance, Inc. nor the names of * its contributors may be used to endorse or promote products * derived from this software without specific prior written * permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /* * verbs.c * * Encapsulates the major functions managing: * o adapters * o endpoints * o connections * o buffer memory */ #include #include #include #include #include #include #include #include "xprt_rdma.h" #include /* * Globals/Macros */ #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) # define RPCDBG_FACILITY RPCDBG_TRANS #endif /* * internal functions */ static void rpcrdma_sendctx_put_locked(struct rpcrdma_sendctx *sc); static void rpcrdma_mrs_create(struct rpcrdma_xprt *r_xprt); static void rpcrdma_mrs_destroy(struct rpcrdma_buffer *buf); static struct rpcrdma_regbuf * rpcrdma_regbuf_alloc(size_t size, enum dma_data_direction direction, gfp_t flags); static void rpcrdma_regbuf_dma_unmap(struct rpcrdma_regbuf *rb); static void rpcrdma_regbuf_free(struct rpcrdma_regbuf *rb); static void rpcrdma_post_recvs(struct rpcrdma_xprt *r_xprt, bool temp); /* Wait for outstanding transport work to finish. ib_drain_qp * handles the drains in the wrong order for us, so open code * them here. */ static void rpcrdma_xprt_drain(struct rpcrdma_xprt *r_xprt) { struct rpcrdma_ia *ia = &r_xprt->rx_ia; /* Flush Receives, then wait for deferred Reply work * to complete. */ ib_drain_rq(ia->ri_id->qp); /* Deferred Reply processing might have scheduled * local invalidations. */ ib_drain_sq(ia->ri_id->qp); } /** * rpcrdma_qp_event_handler - Handle one QP event (error notification) * @event: details of the event * @context: ep that owns QP where event occurred * * Called from the RDMA provider (device driver) possibly in an interrupt * context. */ static void rpcrdma_qp_event_handler(struct ib_event *event, void *context) { struct rpcrdma_ep *ep = context; struct rpcrdma_xprt *r_xprt = container_of(ep, struct rpcrdma_xprt, rx_ep); trace_xprtrdma_qp_event(r_xprt, event); } /** * rpcrdma_wc_send - Invoked by RDMA provider for each polled Send WC * @cq: completion queue (ignored) * @wc: completed WR * */ static void rpcrdma_wc_send(struct ib_cq *cq, struct ib_wc *wc) { struct ib_cqe *cqe = wc->wr_cqe; struct rpcrdma_sendctx *sc = container_of(cqe, struct rpcrdma_sendctx, sc_cqe); /* WARNING: Only wr_cqe and status are reliable at this point */ trace_xprtrdma_wc_send(sc, wc); rpcrdma_sendctx_put_locked(sc); } /** * rpcrdma_wc_receive - Invoked by RDMA provider for each polled Receive WC * @cq: completion queue (ignored) * @wc: completed WR * */ static void rpcrdma_wc_receive(struct ib_cq *cq, struct ib_wc *wc) { struct ib_cqe *cqe = wc->wr_cqe; struct rpcrdma_rep *rep = container_of(cqe, struct rpcrdma_rep, rr_cqe); struct rpcrdma_xprt *r_xprt = rep->rr_rxprt; /* WARNING: Only wr_cqe and status are reliable at this point */ trace_xprtrdma_wc_receive(wc); --r_xprt->rx_ep.rep_receive_count; if (wc->status != IB_WC_SUCCESS) goto out_flushed; /* status == SUCCESS means all fields in wc are trustworthy */ rpcrdma_set_xdrlen(&rep->rr_hdrbuf, wc->byte_len); rep->rr_wc_flags = wc->wc_flags; rep->rr_inv_rkey = wc->ex.invalidate_rkey; ib_dma_sync_single_for_cpu(rdmab_device(rep->rr_rdmabuf), rdmab_addr(rep->rr_rdmabuf), wc->byte_len, DMA_FROM_DEVICE); rpcrdma_post_recvs(r_xprt, false); rpcrdma_reply_handler(rep); return; out_flushed: rpcrdma_recv_buffer_put(rep); } static void rpcrdma_update_connect_private(struct rpcrdma_xprt *r_xprt, struct rdma_conn_param *param) { const struct rpcrdma_connect_private *pmsg = param->private_data; unsigned int rsize, wsize; /* Default settings for RPC-over-RDMA Version One */ r_xprt->rx_ia.ri_implicit_roundup = xprt_rdma_pad_optimize; rsize = RPCRDMA_V1_DEF_INLINE_SIZE; wsize = RPCRDMA_V1_DEF_INLINE_SIZE; if (pmsg && pmsg->cp_magic == rpcrdma_cmp_magic && pmsg->cp_version == RPCRDMA_CMP_VERSION) { r_xprt->rx_ia.ri_implicit_roundup = true; rsize = rpcrdma_decode_buffer_size(pmsg->cp_send_size); wsize = rpcrdma_decode_buffer_size(pmsg->cp_recv_size); } if (rsize < r_xprt->rx_ep.rep_inline_recv) r_xprt->rx_ep.rep_inline_recv = rsize; if (wsize < r_xprt->rx_ep.rep_inline_send) r_xprt->rx_ep.rep_inline_send = wsize; dprintk("RPC: %s: max send %u, max recv %u\n", __func__, r_xprt->rx_ep.rep_inline_send, r_xprt->rx_ep.rep_inline_recv); rpcrdma_set_max_header_sizes(r_xprt); } /** * rpcrdma_cm_event_handler - Handle RDMA CM events * @id: rdma_cm_id on which an event has occurred * @event: details of the event * * Called with @id's mutex held. Returns 1 if caller should * destroy @id, otherwise 0. */ static int rpcrdma_cm_event_handler(struct rdma_cm_id *id, struct rdma_cm_event *event) { struct rpcrdma_xprt *r_xprt = id->context; struct rpcrdma_ia *ia = &r_xprt->rx_ia; struct rpcrdma_ep *ep = &r_xprt->rx_ep; struct rpc_xprt *xprt = &r_xprt->rx_xprt; might_sleep(); trace_xprtrdma_cm_event(r_xprt, event); switch (event->event) { case RDMA_CM_EVENT_ADDR_RESOLVED: case RDMA_CM_EVENT_ROUTE_RESOLVED: ia->ri_async_rc = 0; complete(&ia->ri_done); return 0; case RDMA_CM_EVENT_ADDR_ERROR: ia->ri_async_rc = -EPROTO; complete(&ia->ri_done); return 0; case RDMA_CM_EVENT_ROUTE_ERROR: ia->ri_async_rc = -ENETUNREACH; complete(&ia->ri_done); return 0; case RDMA_CM_EVENT_DEVICE_REMOVAL: #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) pr_info("rpcrdma: removing device %s for %s:%s\n", ia->ri_id->device->name, rpcrdma_addrstr(r_xprt), rpcrdma_portstr(r_xprt)); #endif set_bit(RPCRDMA_IAF_REMOVING, &ia->ri_flags); ep->rep_connected = -ENODEV; xprt_force_disconnect(xprt); wait_for_completion(&ia->ri_remove_done); ia->ri_id = NULL; /* Return 1 to ensure the core destroys the id. */ return 1; case RDMA_CM_EVENT_ESTABLISHED: ++xprt->connect_cookie; ep->rep_connected = 1; rpcrdma_update_connect_private(r_xprt, &event->param.conn); wake_up_all(&ep->rep_connect_wait); break; case RDMA_CM_EVENT_CONNECT_ERROR: ep->rep_connected = -ENOTCONN; goto disconnected; case RDMA_CM_EVENT_UNREACHABLE: ep->rep_connected = -ENETUNREACH; goto disconnected; case RDMA_CM_EVENT_REJECTED: dprintk("rpcrdma: connection to %s:%s rejected: %s\n", rpcrdma_addrstr(r_xprt), rpcrdma_portstr(r_xprt), rdma_reject_msg(id, event->status)); ep->rep_connected = -ECONNREFUSED; if (event->status == IB_CM_REJ_STALE_CONN) ep->rep_connected = -EAGAIN; goto disconnected; case RDMA_CM_EVENT_DISCONNECTED: ep->rep_connected = -ECONNABORTED; disconnected: xprt_force_disconnect(xprt); wake_up_all(&ep->rep_connect_wait); break; default: break; } dprintk("RPC: %s: %s:%s on %s/frwr: %s\n", __func__, rpcrdma_addrstr(r_xprt), rpcrdma_portstr(r_xprt), ia->ri_id->device->name, rdma_event_msg(event->event)); return 0; } static struct rdma_cm_id * rpcrdma_create_id(struct rpcrdma_xprt *xprt, struct rpcrdma_ia *ia) { unsigned long wtimeout = msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT) + 1; struct rdma_cm_id *id; int rc; trace_xprtrdma_conn_start(xprt); init_completion(&ia->ri_done); init_completion(&ia->ri_remove_done); id = rdma_create_id(xprt->rx_xprt.xprt_net, rpcrdma_cm_event_handler, xprt, RDMA_PS_TCP, IB_QPT_RC); if (IS_ERR(id)) return id; ia->ri_async_rc = -ETIMEDOUT; rc = rdma_resolve_addr(id, NULL, (struct sockaddr *)&xprt->rx_xprt.addr, RDMA_RESOLVE_TIMEOUT); if (rc) goto out; rc = wait_for_completion_interruptible_timeout(&ia->ri_done, wtimeout); if (rc < 0) { trace_xprtrdma_conn_tout(xprt); goto out; } rc = ia->ri_async_rc; if (rc) goto out; ia->ri_async_rc = -ETIMEDOUT; rc = rdma_resolve_route(id, RDMA_RESOLVE_TIMEOUT); if (rc) goto out; rc = wait_for_completion_interruptible_timeout(&ia->ri_done, wtimeout); if (rc < 0) { trace_xprtrdma_conn_tout(xprt); goto out; } rc = ia->ri_async_rc; if (rc) goto out; return id; out: rdma_destroy_id(id); return ERR_PTR(rc); } /* * Exported functions. */ /** * rpcrdma_ia_open - Open and initialize an Interface Adapter. * @xprt: transport with IA to (re)initialize * * Returns 0 on success, negative errno if an appropriate * Interface Adapter could not be found and opened. */ int rpcrdma_ia_open(struct rpcrdma_xprt *xprt) { struct rpcrdma_ia *ia = &xprt->rx_ia; int rc; ia->ri_id = rpcrdma_create_id(xprt, ia); if (IS_ERR(ia->ri_id)) { rc = PTR_ERR(ia->ri_id); goto out_err; } ia->ri_pd = ib_alloc_pd(ia->ri_id->device, 0); if (IS_ERR(ia->ri_pd)) { rc = PTR_ERR(ia->ri_pd); pr_err("rpcrdma: ib_alloc_pd() returned %d\n", rc); goto out_err; } switch (xprt_rdma_memreg_strategy) { case RPCRDMA_FRWR: if (frwr_is_supported(ia->ri_id->device)) break; /*FALLTHROUGH*/ default: pr_err("rpcrdma: Device %s does not support memreg mode %d\n", ia->ri_id->device->name, xprt_rdma_memreg_strategy); rc = -EINVAL; goto out_err; } return 0; out_err: rpcrdma_ia_close(ia); return rc; } /** * rpcrdma_ia_remove - Handle device driver unload * @ia: interface adapter being removed * * Divest transport H/W resources associated with this adapter, * but allow it to be restored later. */ void rpcrdma_ia_remove(struct rpcrdma_ia *ia) { struct rpcrdma_xprt *r_xprt = container_of(ia, struct rpcrdma_xprt, rx_ia); struct rpcrdma_ep *ep = &r_xprt->rx_ep; struct rpcrdma_buffer *buf = &r_xprt->rx_buf; struct rpcrdma_req *req; struct rpcrdma_rep *rep; cancel_delayed_work_sync(&buf->rb_refresh_worker); /* This is similar to rpcrdma_ep_destroy, but: * - Don't cancel the connect worker. * - Don't call rpcrdma_ep_disconnect, which waits * for another conn upcall, which will deadlock. * - rdma_disconnect is unneeded, the underlying * connection is already gone. */ if (ia->ri_id->qp) { rpcrdma_xprt_drain(r_xprt); rdma_destroy_qp(ia->ri_id); ia->ri_id->qp = NULL; } ib_free_cq(ep->rep_attr.recv_cq); ep->rep_attr.recv_cq = NULL; ib_free_cq(ep->rep_attr.send_cq); ep->rep_attr.send_cq = NULL; /* The ULP is responsible for ensuring all DMA * mappings and MRs are gone. */ list_for_each_entry(rep, &buf->rb_recv_bufs, rr_list) rpcrdma_regbuf_dma_unmap(rep->rr_rdmabuf); list_for_each_entry(req, &buf->rb_allreqs, rl_all) { rpcrdma_regbuf_dma_unmap(req->rl_rdmabuf); rpcrdma_regbuf_dma_unmap(req->rl_sendbuf); rpcrdma_regbuf_dma_unmap(req->rl_recvbuf); } rpcrdma_mrs_destroy(buf); ib_dealloc_pd(ia->ri_pd); ia->ri_pd = NULL; /* Allow waiters to continue */ complete(&ia->ri_remove_done); trace_xprtrdma_remove(r_xprt); } /** * rpcrdma_ia_close - Clean up/close an IA. * @ia: interface adapter to close * */ void rpcrdma_ia_close(struct rpcrdma_ia *ia) { if (ia->ri_id != NULL && !IS_ERR(ia->ri_id)) { if (ia->ri_id->qp) rdma_destroy_qp(ia->ri_id); rdma_destroy_id(ia->ri_id); } ia->ri_id = NULL; /* If the pd is still busy, xprtrdma missed freeing a resource */ if (ia->ri_pd && !IS_ERR(ia->ri_pd)) ib_dealloc_pd(ia->ri_pd); ia->ri_pd = NULL; } /** * rpcrdma_ep_create - Create unconnected endpoint * @r_xprt: transport to instantiate * * Returns zero on success, or a negative errno. */ int rpcrdma_ep_create(struct rpcrdma_xprt *r_xprt) { struct rpcrdma_ep *ep = &r_xprt->rx_ep; struct rpcrdma_ia *ia = &r_xprt->rx_ia; struct rpcrdma_connect_private *pmsg = &ep->rep_cm_private; struct ib_cq *sendcq, *recvcq; unsigned int max_sge; int rc; ep->rep_max_requests = xprt_rdma_slot_table_entries; ep->rep_inline_send = xprt_rdma_max_inline_write; ep->rep_inline_recv = xprt_rdma_max_inline_read; max_sge = min_t(unsigned int, ia->ri_id->device->attrs.max_send_sge, RPCRDMA_MAX_SEND_SGES); if (max_sge < RPCRDMA_MIN_SEND_SGES) { pr_warn("rpcrdma: HCA provides only %d send SGEs\n", max_sge); return -ENOMEM; } ia->ri_max_send_sges = max_sge; rc = frwr_open(ia, ep); if (rc) return rc; ep->rep_attr.event_handler = rpcrdma_qp_event_handler; ep->rep_attr.qp_context = ep; ep->rep_attr.srq = NULL; ep->rep_attr.cap.max_send_sge = max_sge; ep->rep_attr.cap.max_recv_sge = 1; ep->rep_attr.cap.max_inline_data = 0; ep->rep_attr.sq_sig_type = IB_SIGNAL_REQ_WR; ep->rep_attr.qp_type = IB_QPT_RC; ep->rep_attr.port_num = ~0; dprintk("RPC: %s: requested max: dtos: send %d recv %d; " "iovs: send %d recv %d\n", __func__, ep->rep_attr.cap.max_send_wr, ep->rep_attr.cap.max_recv_wr, ep->rep_attr.cap.max_send_sge, ep->rep_attr.cap.max_recv_sge); ep->rep_send_batch = ep->rep_max_requests >> 3; ep->rep_send_count = ep->rep_send_batch; init_waitqueue_head(&ep->rep_connect_wait); ep->rep_receive_count = 0; sendcq = ib_alloc_cq(ia->ri_id->device, NULL, ep->rep_attr.cap.max_send_wr + 1, ia->ri_id->device->num_comp_vectors > 1 ? 1 : 0, IB_POLL_WORKQUEUE); if (IS_ERR(sendcq)) { rc = PTR_ERR(sendcq); goto out1; } recvcq = ib_alloc_cq(ia->ri_id->device, NULL, ep->rep_attr.cap.max_recv_wr + 1, 0, IB_POLL_WORKQUEUE); if (IS_ERR(recvcq)) { rc = PTR_ERR(recvcq); goto out2; } ep->rep_attr.send_cq = sendcq; ep->rep_attr.recv_cq = recvcq; /* Initialize cma parameters */ memset(&ep->rep_remote_cma, 0, sizeof(ep->rep_remote_cma)); /* Prepare RDMA-CM private message */ pmsg->cp_magic = rpcrdma_cmp_magic; pmsg->cp_version = RPCRDMA_CMP_VERSION; pmsg->cp_flags |= RPCRDMA_CMP_F_SND_W_INV_OK; pmsg->cp_send_size = rpcrdma_encode_buffer_size(ep->rep_inline_send); pmsg->cp_recv_size = rpcrdma_encode_buffer_size(ep->rep_inline_recv); ep->rep_remote_cma.private_data = pmsg; ep->rep_remote_cma.private_data_len = sizeof(*pmsg); /* Client offers RDMA Read but does not initiate */ ep->rep_remote_cma.initiator_depth = 0; ep->rep_remote_cma.responder_resources = min_t(int, U8_MAX, ia->ri_id->device->attrs.max_qp_rd_atom); /* Limit transport retries so client can detect server * GID changes quickly. RPC layer handles re-establishing * transport connection and retransmission. */ ep->rep_remote_cma.retry_count = 6; /* RPC-over-RDMA handles its own flow control. In addition, * make all RNR NAKs visible so we know that RPC-over-RDMA * flow control is working correctly (no NAKs should be seen). */ ep->rep_remote_cma.flow_control = 0; ep->rep_remote_cma.rnr_retry_count = 0; return 0; out2: ib_free_cq(sendcq); out1: return rc; } /** * rpcrdma_ep_destroy - Disconnect and destroy endpoint. * @r_xprt: transport instance to shut down * */ void rpcrdma_ep_destroy(struct rpcrdma_xprt *r_xprt) { struct rpcrdma_ep *ep = &r_xprt->rx_ep; struct rpcrdma_ia *ia = &r_xprt->rx_ia; if (ia->ri_id && ia->ri_id->qp) { rpcrdma_ep_disconnect(ep, ia); rdma_destroy_qp(ia->ri_id); ia->ri_id->qp = NULL; } if (ep->rep_attr.recv_cq) ib_free_cq(ep->rep_attr.recv_cq); if (ep->rep_attr.send_cq) ib_free_cq(ep->rep_attr.send_cq); } /* Re-establish a connection after a device removal event. * Unlike a normal reconnection, a fresh PD and a new set * of MRs and buffers is needed. */ static int rpcrdma_ep_recreate_xprt(struct rpcrdma_xprt *r_xprt, struct rpcrdma_ep *ep, struct rpcrdma_ia *ia) { int rc, err; trace_xprtrdma_reinsert(r_xprt); rc = -EHOSTUNREACH; if (rpcrdma_ia_open(r_xprt)) goto out1; rc = -ENOMEM; err = rpcrdma_ep_create(r_xprt); if (err) { pr_err("rpcrdma: rpcrdma_ep_create returned %d\n", err); goto out2; } rc = -ENETUNREACH; err = rdma_create_qp(ia->ri_id, ia->ri_pd, &ep->rep_attr); if (err) { pr_err("rpcrdma: rdma_create_qp returned %d\n", err); goto out3; } rpcrdma_mrs_create(r_xprt); return 0; out3: rpcrdma_ep_destroy(r_xprt); out2: rpcrdma_ia_close(ia); out1: return rc; } static int rpcrdma_ep_reconnect(struct rpcrdma_xprt *r_xprt, struct rpcrdma_ep *ep, struct rpcrdma_ia *ia) { struct rdma_cm_id *id, *old; int err, rc; trace_xprtrdma_reconnect(r_xprt); rpcrdma_ep_disconnect(ep, ia); rc = -EHOSTUNREACH; id = rpcrdma_create_id(r_xprt, ia); if (IS_ERR(id)) goto out; /* As long as the new ID points to the same device as the * old ID, we can reuse the transport's existing PD and all * previously allocated MRs. Also, the same device means * the transport's previous DMA mappings are still valid. * * This is a sanity check only. There should be no way these * point to two different devices here. */ old = id; rc = -ENETUNREACH; if (ia->ri_id->device != id->device) { pr_err("rpcrdma: can't reconnect on different device!\n"); goto out_destroy; } err = rdma_create_qp(id, ia->ri_pd, &ep->rep_attr); if (err) goto out_destroy; /* Atomically replace the transport's ID and QP. */ rc = 0; old = ia->ri_id; ia->ri_id = id; rdma_destroy_qp(old); out_destroy: rdma_destroy_id(old); out: return rc; } /* * Connect unconnected endpoint. */ int rpcrdma_ep_connect(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia) { struct rpcrdma_xprt *r_xprt = container_of(ia, struct rpcrdma_xprt, rx_ia); struct rpc_xprt *xprt = &r_xprt->rx_xprt; int rc; retry: switch (ep->rep_connected) { case 0: dprintk("RPC: %s: connecting...\n", __func__); rc = rdma_create_qp(ia->ri_id, ia->ri_pd, &ep->rep_attr); if (rc) { rc = -ENETUNREACH; goto out_noupdate; } break; case -ENODEV: rc = rpcrdma_ep_recreate_xprt(r_xprt, ep, ia); if (rc) goto out_noupdate; break; default: rc = rpcrdma_ep_reconnect(r_xprt, ep, ia); if (rc) goto out; } ep->rep_connected = 0; xprt_clear_connected(xprt); rpcrdma_post_recvs(r_xprt, true); rc = rdma_connect(ia->ri_id, &ep->rep_remote_cma); if (rc) goto out; wait_event_interruptible(ep->rep_connect_wait, ep->rep_connected != 0); if (ep->rep_connected <= 0) { if (ep->rep_connected == -EAGAIN) goto retry; rc = ep->rep_connected; goto out; } dprintk("RPC: %s: connected\n", __func__); out: if (rc) ep->rep_connected = rc; out_noupdate: return rc; } /** * rpcrdma_ep_disconnect - Disconnect underlying transport * @ep: endpoint to disconnect * @ia: associated interface adapter * * This is separate from destroy to facilitate the ability * to reconnect without recreating the endpoint. * * This call is not reentrant, and must not be made in parallel * on the same endpoint. */ void rpcrdma_ep_disconnect(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia) { struct rpcrdma_xprt *r_xprt = container_of(ep, struct rpcrdma_xprt, rx_ep); int rc; /* returns without wait if ID is not connected */ rc = rdma_disconnect(ia->ri_id); if (!rc) wait_event_interruptible(ep->rep_connect_wait, ep->rep_connected != 1); else ep->rep_connected = rc; trace_xprtrdma_disconnect(r_xprt, rc); rpcrdma_xprt_drain(r_xprt); } /* Fixed-size circular FIFO queue. This implementation is wait-free and * lock-free. * * Consumer is the code path that posts Sends. This path dequeues a * sendctx for use by a Send operation. Multiple consumer threads * are serialized by the RPC transport lock, which allows only one * ->send_request call at a time. * * Producer is the code path that handles Send completions. This path * enqueues a sendctx that has been completed. Multiple producer * threads are serialized by the ib_poll_cq() function. */ /* rpcrdma_sendctxs_destroy() assumes caller has already quiesced * queue activity, and rpcrdma_xprt_drain has flushed all remaining * Send requests. */ static void rpcrdma_sendctxs_destroy(struct rpcrdma_buffer *buf) { unsigned long i; for (i = 0; i <= buf->rb_sc_last; i++) kfree(buf->rb_sc_ctxs[i]); kfree(buf->rb_sc_ctxs); } static struct rpcrdma_sendctx *rpcrdma_sendctx_create(struct rpcrdma_ia *ia) { struct rpcrdma_sendctx *sc; sc = kzalloc(struct_size(sc, sc_sges, ia->ri_max_send_sges), GFP_KERNEL); if (!sc) return NULL; sc->sc_wr.wr_cqe = &sc->sc_cqe; sc->sc_wr.sg_list = sc->sc_sges; sc->sc_wr.opcode = IB_WR_SEND; sc->sc_cqe.done = rpcrdma_wc_send; return sc; } static int rpcrdma_sendctxs_create(struct rpcrdma_xprt *r_xprt) { struct rpcrdma_buffer *buf = &r_xprt->rx_buf; struct rpcrdma_sendctx *sc; unsigned long i; /* Maximum number of concurrent outstanding Send WRs. Capping * the circular queue size stops Send Queue overflow by causing * the ->send_request call to fail temporarily before too many * Sends are posted. */ i = buf->rb_max_requests + RPCRDMA_MAX_BC_REQUESTS; dprintk("RPC: %s: allocating %lu send_ctxs\n", __func__, i); buf->rb_sc_ctxs = kcalloc(i, sizeof(sc), GFP_KERNEL); if (!buf->rb_sc_ctxs) return -ENOMEM; buf->rb_sc_last = i - 1; for (i = 0; i <= buf->rb_sc_last; i++) { sc = rpcrdma_sendctx_create(&r_xprt->rx_ia); if (!sc) return -ENOMEM; sc->sc_xprt = r_xprt; buf->rb_sc_ctxs[i] = sc; } return 0; } /* The sendctx queue is not guaranteed to have a size that is a * power of two, thus the helpers in circ_buf.h cannot be used. * The other option is to use modulus (%), which can be expensive. */ static unsigned long rpcrdma_sendctx_next(struct rpcrdma_buffer *buf, unsigned long item) { return likely(item < buf->rb_sc_last) ? item + 1 : 0; } /** * rpcrdma_sendctx_get_locked - Acquire a send context * @r_xprt: controlling transport instance * * Returns pointer to a free send completion context; or NULL if * the queue is empty. * * Usage: Called to acquire an SGE array before preparing a Send WR. * * The caller serializes calls to this function (per transport), and * provides an effective memory barrier that flushes the new value * of rb_sc_head. */ struct rpcrdma_sendctx *rpcrdma_sendctx_get_locked(struct rpcrdma_xprt *r_xprt) { struct rpcrdma_buffer *buf = &r_xprt->rx_buf; struct rpcrdma_sendctx *sc; unsigned long next_head; next_head = rpcrdma_sendctx_next(buf, buf->rb_sc_head); if (next_head == READ_ONCE(buf->rb_sc_tail)) goto out_emptyq; /* ORDER: item must be accessed _before_ head is updated */ sc = buf->rb_sc_ctxs[next_head]; /* Releasing the lock in the caller acts as a memory * barrier that flushes rb_sc_head. */ buf->rb_sc_head = next_head; return sc; out_emptyq: /* The queue is "empty" if there have not been enough Send * completions recently. This is a sign the Send Queue is * backing up. Cause the caller to pause and try again. */ xprt_wait_for_buffer_space(&r_xprt->rx_xprt); r_xprt->rx_stats.empty_sendctx_q++; return NULL; } /** * rpcrdma_sendctx_put_locked - Release a send context * @sc: send context to release * * Usage: Called from Send completion to return a sendctxt * to the queue. * * The caller serializes calls to this function (per transport). */ static void rpcrdma_sendctx_put_locked(struct rpcrdma_sendctx *sc) { struct rpcrdma_buffer *buf = &sc->sc_xprt->rx_buf; unsigned long next_tail; /* Unmap SGEs of previously completed but unsignaled * Sends by walking up the queue until @sc is found. */ next_tail = buf->rb_sc_tail; do { next_tail = rpcrdma_sendctx_next(buf, next_tail); /* ORDER: item must be accessed _before_ tail is updated */ rpcrdma_sendctx_unmap(buf->rb_sc_ctxs[next_tail]); } while (buf->rb_sc_ctxs[next_tail] != sc); /* Paired with READ_ONCE */ smp_store_release(&buf->rb_sc_tail, next_tail); xprt_write_space(&sc->sc_xprt->rx_xprt); } static void rpcrdma_mrs_create(struct rpcrdma_xprt *r_xprt) { struct rpcrdma_buffer *buf = &r_xprt->rx_buf; struct rpcrdma_ia *ia = &r_xprt->rx_ia; unsigned int count; LIST_HEAD(free); LIST_HEAD(all); for (count = 0; count < ia->ri_max_segs; count++) { struct rpcrdma_mr *mr; int rc; mr = kzalloc(sizeof(*mr), GFP_KERNEL); if (!mr) break; rc = frwr_init_mr(ia, mr); if (rc) { kfree(mr); break; } mr->mr_xprt = r_xprt; list_add(&mr->mr_list, &free); list_add(&mr->mr_all, &all); } spin_lock(&buf->rb_mrlock); list_splice(&free, &buf->rb_mrs); list_splice(&all, &buf->rb_all); r_xprt->rx_stats.mrs_allocated += count; spin_unlock(&buf->rb_mrlock); trace_xprtrdma_createmrs(r_xprt, count); } static void rpcrdma_mr_refresh_worker(struct work_struct *work) { struct rpcrdma_buffer *buf = container_of(work, struct rpcrdma_buffer, rb_refresh_worker.work); struct rpcrdma_xprt *r_xprt = container_of(buf, struct rpcrdma_xprt, rx_buf); rpcrdma_mrs_create(r_xprt); xprt_write_space(&r_xprt->rx_xprt); } /** * rpcrdma_req_create - Allocate an rpcrdma_req object * @r_xprt: controlling r_xprt * @size: initial size, in bytes, of send and receive buffers * @flags: GFP flags passed to memory allocators * * Returns an allocated and fully initialized rpcrdma_req or NULL. */ struct rpcrdma_req *rpcrdma_req_create(struct rpcrdma_xprt *r_xprt, size_t size, gfp_t flags) { struct rpcrdma_buffer *buffer = &r_xprt->rx_buf; struct rpcrdma_regbuf *rb; struct rpcrdma_req *req; req = kzalloc(sizeof(*req), flags); if (req == NULL) goto out1; rb = rpcrdma_regbuf_alloc(RPCRDMA_HDRBUF_SIZE, DMA_TO_DEVICE, flags); if (!rb) goto out2; req->rl_rdmabuf = rb; xdr_buf_init(&req->rl_hdrbuf, rdmab_data(rb), rdmab_length(rb)); req->rl_sendbuf = rpcrdma_regbuf_alloc(size, DMA_TO_DEVICE, flags); if (!req->rl_sendbuf) goto out3; req->rl_recvbuf = rpcrdma_regbuf_alloc(size, DMA_NONE, flags); if (!req->rl_recvbuf) goto out4; INIT_LIST_HEAD(&req->rl_registered); spin_lock(&buffer->rb_lock); list_add(&req->rl_all, &buffer->rb_allreqs); spin_unlock(&buffer->rb_lock); return req; out4: kfree(req->rl_sendbuf); out3: kfree(req->rl_rdmabuf); out2: kfree(req); out1: return NULL; } static struct rpcrdma_rep *rpcrdma_rep_create(struct rpcrdma_xprt *r_xprt, bool temp) { struct rpcrdma_rep *rep; rep = kzalloc(sizeof(*rep), GFP_KERNEL); if (rep == NULL) goto out; rep->rr_rdmabuf = rpcrdma_regbuf_alloc(r_xprt->rx_ep.rep_inline_recv, DMA_FROM_DEVICE, GFP_KERNEL); if (!rep->rr_rdmabuf) goto out_free; xdr_buf_init(&rep->rr_hdrbuf, rdmab_data(rep->rr_rdmabuf), rdmab_length(rep->rr_rdmabuf)); rep->rr_cqe.done = rpcrdma_wc_receive; rep->rr_rxprt = r_xprt; rep->rr_recv_wr.next = NULL; rep->rr_recv_wr.wr_cqe = &rep->rr_cqe; rep->rr_recv_wr.sg_list = &rep->rr_rdmabuf->rg_iov; rep->rr_recv_wr.num_sge = 1; rep->rr_temp = temp; return rep; out_free: kfree(rep); out: return NULL; } /** * rpcrdma_buffer_create - Create initial set of req/rep objects * @r_xprt: transport instance to (re)initialize * * Returns zero on success, otherwise a negative errno. */ int rpcrdma_buffer_create(struct rpcrdma_xprt *r_xprt) { struct rpcrdma_buffer *buf = &r_xprt->rx_buf; int i, rc; buf->rb_max_requests = r_xprt->rx_ep.rep_max_requests; buf->rb_bc_srv_max_requests = 0; spin_lock_init(&buf->rb_mrlock); spin_lock_init(&buf->rb_lock); INIT_LIST_HEAD(&buf->rb_mrs); INIT_LIST_HEAD(&buf->rb_all); INIT_DELAYED_WORK(&buf->rb_refresh_worker, rpcrdma_mr_refresh_worker); rpcrdma_mrs_create(r_xprt); INIT_LIST_HEAD(&buf->rb_send_bufs); INIT_LIST_HEAD(&buf->rb_allreqs); rc = -ENOMEM; for (i = 0; i < buf->rb_max_requests; i++) { struct rpcrdma_req *req; req = rpcrdma_req_create(r_xprt, RPCRDMA_V1_DEF_INLINE_SIZE, GFP_KERNEL); if (!req) goto out; list_add(&req->rl_list, &buf->rb_send_bufs); } buf->rb_credits = 1; INIT_LIST_HEAD(&buf->rb_recv_bufs); rc = rpcrdma_sendctxs_create(r_xprt); if (rc) goto out; return 0; out: rpcrdma_buffer_destroy(buf); return rc; } static void rpcrdma_rep_destroy(struct rpcrdma_rep *rep) { rpcrdma_regbuf_free(rep->rr_rdmabuf); kfree(rep); } /** * rpcrdma_req_destroy - Destroy an rpcrdma_req object * @req: unused object to be destroyed * * This function assumes that the caller prevents concurrent device * unload and transport tear-down. */ void rpcrdma_req_destroy(struct rpcrdma_req *req) { list_del(&req->rl_all); rpcrdma_regbuf_free(req->rl_recvbuf); rpcrdma_regbuf_free(req->rl_sendbuf); rpcrdma_regbuf_free(req->rl_rdmabuf); kfree(req); } static void rpcrdma_mrs_destroy(struct rpcrdma_buffer *buf) { struct rpcrdma_xprt *r_xprt = container_of(buf, struct rpcrdma_xprt, rx_buf); struct rpcrdma_mr *mr; unsigned int count; count = 0; spin_lock(&buf->rb_mrlock); while (!list_empty(&buf->rb_all)) { mr = list_entry(buf->rb_all.next, struct rpcrdma_mr, mr_all); list_del(&mr->mr_all); spin_unlock(&buf->rb_mrlock); /* Ensure MW is not on any rl_registered list */ if (!list_empty(&mr->mr_list)) list_del(&mr->mr_list); frwr_release_mr(mr); count++; spin_lock(&buf->rb_mrlock); } spin_unlock(&buf->rb_mrlock); r_xprt->rx_stats.mrs_allocated = 0; dprintk("RPC: %s: released %u MRs\n", __func__, count); } /** * rpcrdma_buffer_destroy - Release all hw resources * @buf: root control block for resources * * ORDERING: relies on a prior rpcrdma_xprt_drain : * - No more Send or Receive completions can occur * - All MRs, reps, and reqs are returned to their free lists */ void rpcrdma_buffer_destroy(struct rpcrdma_buffer *buf) { cancel_delayed_work_sync(&buf->rb_refresh_worker); rpcrdma_sendctxs_destroy(buf); while (!list_empty(&buf->rb_recv_bufs)) { struct rpcrdma_rep *rep; rep = list_first_entry(&buf->rb_recv_bufs, struct rpcrdma_rep, rr_list); list_del(&rep->rr_list); rpcrdma_rep_destroy(rep); } while (!list_empty(&buf->rb_send_bufs)) { struct rpcrdma_req *req; req = list_first_entry(&buf->rb_send_bufs, struct rpcrdma_req, rl_list); list_del(&req->rl_list); rpcrdma_req_destroy(req); } rpcrdma_mrs_destroy(buf); } /** * rpcrdma_mr_get - Allocate an rpcrdma_mr object * @r_xprt: controlling transport * * Returns an initialized rpcrdma_mr or NULL if no free * rpcrdma_mr objects are available. */ struct rpcrdma_mr * rpcrdma_mr_get(struct rpcrdma_xprt *r_xprt) { struct rpcrdma_buffer *buf = &r_xprt->rx_buf; struct rpcrdma_mr *mr = NULL; spin_lock(&buf->rb_mrlock); if (!list_empty(&buf->rb_mrs)) mr = rpcrdma_mr_pop(&buf->rb_mrs); spin_unlock(&buf->rb_mrlock); if (!mr) goto out_nomrs; return mr; out_nomrs: trace_xprtrdma_nomrs(r_xprt); if (r_xprt->rx_ep.rep_connected != -ENODEV) schedule_delayed_work(&buf->rb_refresh_worker, 0); /* Allow the reply handler and refresh worker to run */ cond_resched(); return NULL; } static void __rpcrdma_mr_put(struct rpcrdma_buffer *buf, struct rpcrdma_mr *mr) { spin_lock(&buf->rb_mrlock); rpcrdma_mr_push(mr, &buf->rb_mrs); spin_unlock(&buf->rb_mrlock); } /** * rpcrdma_mr_put - Release an rpcrdma_mr object * @mr: object to release * */ void rpcrdma_mr_put(struct rpcrdma_mr *mr) { __rpcrdma_mr_put(&mr->mr_xprt->rx_buf, mr); } /** * rpcrdma_mr_unmap_and_put - DMA unmap an MR and release it * @mr: object to release * */ void rpcrdma_mr_unmap_and_put(struct rpcrdma_mr *mr) { struct rpcrdma_xprt *r_xprt = mr->mr_xprt; if (mr->mr_dir != DMA_NONE) { trace_xprtrdma_mr_unmap(mr); ib_dma_unmap_sg(r_xprt->rx_ia.ri_id->device, mr->mr_sg, mr->mr_nents, mr->mr_dir); mr->mr_dir = DMA_NONE; } __rpcrdma_mr_put(&r_xprt->rx_buf, mr); } /** * rpcrdma_buffer_get - Get a request buffer * @buffers: Buffer pool from which to obtain a buffer * * Returns a fresh rpcrdma_req, or NULL if none are available. */ struct rpcrdma_req * rpcrdma_buffer_get(struct rpcrdma_buffer *buffers) { struct rpcrdma_req *req; spin_lock(&buffers->rb_lock); req = list_first_entry_or_null(&buffers->rb_send_bufs, struct rpcrdma_req, rl_list); if (req) list_del_init(&req->rl_list); spin_unlock(&buffers->rb_lock); return req; } /** * rpcrdma_buffer_put - Put request/reply buffers back into pool * @buffers: buffer pool * @req: object to return * */ void rpcrdma_buffer_put(struct rpcrdma_buffer *buffers, struct rpcrdma_req *req) { struct rpcrdma_rep *rep = req->rl_reply; req->rl_reply = NULL; spin_lock(&buffers->rb_lock); list_add(&req->rl_list, &buffers->rb_send_bufs); if (rep) { if (!rep->rr_temp) { list_add(&rep->rr_list, &buffers->rb_recv_bufs); rep = NULL; } } spin_unlock(&buffers->rb_lock); if (rep) rpcrdma_rep_destroy(rep); } /* * Put reply buffers back into pool when not attached to * request. This happens in error conditions. */ void rpcrdma_recv_buffer_put(struct rpcrdma_rep *rep) { struct rpcrdma_buffer *buffers = &rep->rr_rxprt->rx_buf; if (!rep->rr_temp) { spin_lock(&buffers->rb_lock); list_add(&rep->rr_list, &buffers->rb_recv_bufs); spin_unlock(&buffers->rb_lock); } else { rpcrdma_rep_destroy(rep); } } /* Returns a pointer to a rpcrdma_regbuf object, or NULL. * * xprtrdma uses a regbuf for posting an outgoing RDMA SEND, or for * receiving the payload of RDMA RECV operations. During Long Calls * or Replies they may be registered externally via frwr_map. */ static struct rpcrdma_regbuf * rpcrdma_regbuf_alloc(size_t size, enum dma_data_direction direction, gfp_t flags) { struct rpcrdma_regbuf *rb; rb = kmalloc(sizeof(*rb), flags); if (!rb) return NULL; rb->rg_data = kmalloc(size, flags); if (!rb->rg_data) { kfree(rb); return NULL; } rb->rg_device = NULL; rb->rg_direction = direction; rb->rg_iov.length = size; return rb; } /** * rpcrdma_regbuf_realloc - re-allocate a SEND/RECV buffer * @rb: regbuf to reallocate * @size: size of buffer to be allocated, in bytes * @flags: GFP flags * * Returns true if reallocation was successful. If false is * returned, @rb is left untouched. */ bool rpcrdma_regbuf_realloc(struct rpcrdma_regbuf *rb, size_t size, gfp_t flags) { void *buf; buf = kmalloc(size, flags); if (!buf) return false; rpcrdma_regbuf_dma_unmap(rb); kfree(rb->rg_data); rb->rg_data = buf; rb->rg_iov.length = size; return true; } /** * __rpcrdma_regbuf_dma_map - DMA-map a regbuf * @r_xprt: controlling transport instance * @rb: regbuf to be mapped * * Returns true if the buffer is now DMA mapped to @r_xprt's device */ bool __rpcrdma_regbuf_dma_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_regbuf *rb) { struct ib_device *device = r_xprt->rx_ia.ri_id->device; if (rb->rg_direction == DMA_NONE) return false; rb->rg_iov.addr = ib_dma_map_single(device, rdmab_data(rb), rdmab_length(rb), rb->rg_direction); if (ib_dma_mapping_error(device, rdmab_addr(rb))) { trace_xprtrdma_dma_maperr(rdmab_addr(rb)); return false; } rb->rg_device = device; rb->rg_iov.lkey = r_xprt->rx_ia.ri_pd->local_dma_lkey; return true; } static void rpcrdma_regbuf_dma_unmap(struct rpcrdma_regbuf *rb) { if (!rb) return; if (!rpcrdma_regbuf_is_mapped(rb)) return; ib_dma_unmap_single(rb->rg_device, rdmab_addr(rb), rdmab_length(rb), rb->rg_direction); rb->rg_device = NULL; } static void rpcrdma_regbuf_free(struct rpcrdma_regbuf *rb) { rpcrdma_regbuf_dma_unmap(rb); if (rb) kfree(rb->rg_data); kfree(rb); } /** * rpcrdma_ep_post - Post WRs to a transport's Send Queue * @ia: transport's device information * @ep: transport's RDMA endpoint information * @req: rpcrdma_req containing the Send WR to post * * Returns 0 if the post was successful, otherwise -ENOTCONN * is returned. */ int rpcrdma_ep_post(struct rpcrdma_ia *ia, struct rpcrdma_ep *ep, struct rpcrdma_req *req) { struct ib_send_wr *send_wr = &req->rl_sendctx->sc_wr; int rc; if (!ep->rep_send_count || kref_read(&req->rl_kref) > 1) { send_wr->send_flags |= IB_SEND_SIGNALED; ep->rep_send_count = ep->rep_send_batch; } else { send_wr->send_flags &= ~IB_SEND_SIGNALED; --ep->rep_send_count; } rc = frwr_send(ia, req); trace_xprtrdma_post_send(req, rc); if (rc) return -ENOTCONN; return 0; } static void rpcrdma_post_recvs(struct rpcrdma_xprt *r_xprt, bool temp) { struct rpcrdma_buffer *buf = &r_xprt->rx_buf; struct rpcrdma_ep *ep = &r_xprt->rx_ep; struct ib_recv_wr *i, *wr, *bad_wr; struct rpcrdma_rep *rep; int needed, count, rc; rc = 0; count = 0; needed = buf->rb_credits + (buf->rb_bc_srv_max_requests << 1); if (ep->rep_receive_count > needed) goto out; needed -= ep->rep_receive_count; if (!temp) needed += RPCRDMA_MAX_RECV_BATCH; /* fast path: all needed reps can be found on the free list */ wr = NULL; spin_lock(&buf->rb_lock); while (needed) { rep = list_first_entry_or_null(&buf->rb_recv_bufs, struct rpcrdma_rep, rr_list); if (!rep) break; list_del(&rep->rr_list); rep->rr_recv_wr.next = wr; wr = &rep->rr_recv_wr; --needed; } spin_unlock(&buf->rb_lock); while (needed) { rep = rpcrdma_rep_create(r_xprt, temp); if (!rep) break; rep->rr_recv_wr.next = wr; wr = &rep->rr_recv_wr; --needed; } if (!wr) goto out; for (i = wr; i; i = i->next) { rep = container_of(i, struct rpcrdma_rep, rr_recv_wr); if (!rpcrdma_regbuf_dma_map(r_xprt, rep->rr_rdmabuf)) goto release_wrs; trace_xprtrdma_post_recv(rep->rr_recv_wr.wr_cqe); ++count; } rc = ib_post_recv(r_xprt->rx_ia.ri_id->qp, wr, (const struct ib_recv_wr **)&bad_wr); out: trace_xprtrdma_post_recvs(r_xprt, count, rc); if (rc) { for (wr = bad_wr; wr;) { struct rpcrdma_rep *rep; rep = container_of(wr, struct rpcrdma_rep, rr_recv_wr); wr = wr->next; rpcrdma_recv_buffer_put(rep); --count; } } ep->rep_receive_count += count; return; release_wrs: for (i = wr; i;) { rep = container_of(i, struct rpcrdma_rep, rr_recv_wr); i = i->next; rpcrdma_recv_buffer_put(rep); } }