1 // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
3 * Copyright (c) 2014-2017 Oracle. All rights reserved.
4 * Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
6 * This software is available to you under a choice of one of two
7 * licenses. You may choose to be licensed under the terms of the GNU
8 * General Public License (GPL) Version 2, available from the file
9 * COPYING in the main directory of this source tree, or the BSD-type
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
16 * Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
19 * Redistributions in binary form must reproduce the above
20 * copyright notice, this list of conditions and the following
21 * disclaimer in the documentation and/or other materials provided
22 * with the distribution.
24 * Neither the name of the Network Appliance, Inc. nor the names of
25 * its contributors may be used to endorse or promote products
26 * derived from this software without specific prior written
29 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
30 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
31 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
32 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
33 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
34 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
35 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
39 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
45 * Encapsulates the major functions managing:
52 #include <linux/interrupt.h>
53 #include <linux/slab.h>
54 #include <linux/sunrpc/addr.h>
55 #include <linux/sunrpc/svc_rdma.h>
56 #include <linux/log2.h>
58 #include <asm-generic/barrier.h>
59 #include <asm/bitops.h>
61 #include <rdma/ib_cm.h>
63 #include "xprt_rdma.h"
64 #include <trace/events/rpcrdma.h>
70 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
71 # define RPCDBG_FACILITY RPCDBG_TRANS
77 static int rpcrdma_sendctxs_create(struct rpcrdma_xprt *r_xprt);
78 static void rpcrdma_sendctxs_destroy(struct rpcrdma_xprt *r_xprt);
79 static void rpcrdma_sendctx_put_locked(struct rpcrdma_xprt *r_xprt,
80 struct rpcrdma_sendctx *sc);
81 static int rpcrdma_reqs_setup(struct rpcrdma_xprt *r_xprt);
82 static void rpcrdma_reqs_reset(struct rpcrdma_xprt *r_xprt);
83 static void rpcrdma_rep_destroy(struct rpcrdma_rep *rep);
84 static void rpcrdma_reps_unmap(struct rpcrdma_xprt *r_xprt);
85 static void rpcrdma_mrs_create(struct rpcrdma_xprt *r_xprt);
86 static void rpcrdma_mrs_destroy(struct rpcrdma_xprt *r_xprt);
87 static struct rpcrdma_regbuf *
88 rpcrdma_regbuf_alloc(size_t size, enum dma_data_direction direction,
90 static void rpcrdma_regbuf_dma_unmap(struct rpcrdma_regbuf *rb);
91 static void rpcrdma_regbuf_free(struct rpcrdma_regbuf *rb);
93 /* Wait for outstanding transport work to finish. ib_drain_qp
94 * handles the drains in the wrong order for us, so open code
97 static void rpcrdma_xprt_drain(struct rpcrdma_xprt *r_xprt)
99 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
101 /* Flush Receives, then wait for deferred Reply work
104 ib_drain_rq(ia->ri_id->qp);
106 /* Deferred Reply processing might have scheduled
107 * local invalidations.
109 ib_drain_sq(ia->ri_id->qp);
113 * rpcrdma_qp_event_handler - Handle one QP event (error notification)
114 * @event: details of the event
115 * @context: ep that owns QP where event occurred
117 * Called from the RDMA provider (device driver) possibly in an interrupt
121 rpcrdma_qp_event_handler(struct ib_event *event, void *context)
123 struct rpcrdma_ep *ep = context;
124 struct rpcrdma_xprt *r_xprt = container_of(ep, struct rpcrdma_xprt,
127 trace_xprtrdma_qp_event(r_xprt, event);
131 * rpcrdma_wc_send - Invoked by RDMA provider for each polled Send WC
132 * @cq: completion queue
137 rpcrdma_wc_send(struct ib_cq *cq, struct ib_wc *wc)
139 struct ib_cqe *cqe = wc->wr_cqe;
140 struct rpcrdma_sendctx *sc =
141 container_of(cqe, struct rpcrdma_sendctx, sc_cqe);
143 /* WARNING: Only wr_cqe and status are reliable at this point */
144 trace_xprtrdma_wc_send(sc, wc);
145 rpcrdma_sendctx_put_locked((struct rpcrdma_xprt *)cq->cq_context, sc);
149 * rpcrdma_wc_receive - Invoked by RDMA provider for each polled Receive WC
150 * @cq: completion queue (ignored)
155 rpcrdma_wc_receive(struct ib_cq *cq, struct ib_wc *wc)
157 struct ib_cqe *cqe = wc->wr_cqe;
158 struct rpcrdma_rep *rep = container_of(cqe, struct rpcrdma_rep,
160 struct rpcrdma_xprt *r_xprt = rep->rr_rxprt;
162 /* WARNING: Only wr_cqe and status are reliable at this point */
163 trace_xprtrdma_wc_receive(wc);
164 --r_xprt->rx_ep.rep_receive_count;
165 if (wc->status != IB_WC_SUCCESS)
168 /* status == SUCCESS means all fields in wc are trustworthy */
169 rpcrdma_set_xdrlen(&rep->rr_hdrbuf, wc->byte_len);
170 rep->rr_wc_flags = wc->wc_flags;
171 rep->rr_inv_rkey = wc->ex.invalidate_rkey;
173 ib_dma_sync_single_for_cpu(rdmab_device(rep->rr_rdmabuf),
174 rdmab_addr(rep->rr_rdmabuf),
175 wc->byte_len, DMA_FROM_DEVICE);
177 rpcrdma_reply_handler(rep);
181 rpcrdma_rep_destroy(rep);
184 static void rpcrdma_update_cm_private(struct rpcrdma_xprt *r_xprt,
185 struct rdma_conn_param *param)
187 const struct rpcrdma_connect_private *pmsg = param->private_data;
188 struct rpcrdma_ep *ep = &r_xprt->rx_ep;
189 unsigned int rsize, wsize;
191 /* Default settings for RPC-over-RDMA Version One */
192 r_xprt->rx_ia.ri_implicit_roundup = xprt_rdma_pad_optimize;
193 rsize = RPCRDMA_V1_DEF_INLINE_SIZE;
194 wsize = RPCRDMA_V1_DEF_INLINE_SIZE;
197 pmsg->cp_magic == rpcrdma_cmp_magic &&
198 pmsg->cp_version == RPCRDMA_CMP_VERSION) {
199 r_xprt->rx_ia.ri_implicit_roundup = true;
200 rsize = rpcrdma_decode_buffer_size(pmsg->cp_send_size);
201 wsize = rpcrdma_decode_buffer_size(pmsg->cp_recv_size);
204 if (rsize < ep->rep_inline_recv)
205 ep->rep_inline_recv = rsize;
206 if (wsize < ep->rep_inline_send)
207 ep->rep_inline_send = wsize;
209 rpcrdma_set_max_header_sizes(r_xprt);
213 * rpcrdma_cm_event_handler - Handle RDMA CM events
214 * @id: rdma_cm_id on which an event has occurred
215 * @event: details of the event
217 * Called with @id's mutex held. Returns 1 if caller should
218 * destroy @id, otherwise 0.
221 rpcrdma_cm_event_handler(struct rdma_cm_id *id, struct rdma_cm_event *event)
223 struct rpcrdma_xprt *r_xprt = id->context;
224 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
225 struct rpcrdma_ep *ep = &r_xprt->rx_ep;
226 struct rpc_xprt *xprt = &r_xprt->rx_xprt;
230 trace_xprtrdma_cm_event(r_xprt, event);
231 switch (event->event) {
232 case RDMA_CM_EVENT_ADDR_RESOLVED:
233 case RDMA_CM_EVENT_ROUTE_RESOLVED:
235 complete(&ia->ri_done);
237 case RDMA_CM_EVENT_ADDR_ERROR:
238 ia->ri_async_rc = -EPROTO;
239 complete(&ia->ri_done);
241 case RDMA_CM_EVENT_ROUTE_ERROR:
242 ia->ri_async_rc = -ENETUNREACH;
243 complete(&ia->ri_done);
245 case RDMA_CM_EVENT_DEVICE_REMOVAL:
246 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
247 pr_info("rpcrdma: removing device %s for %s:%s\n",
248 ia->ri_id->device->name,
249 rpcrdma_addrstr(r_xprt), rpcrdma_portstr(r_xprt));
251 init_completion(&ia->ri_remove_done);
252 set_bit(RPCRDMA_IAF_REMOVING, &ia->ri_flags);
253 ep->rep_connected = -ENODEV;
254 xprt_force_disconnect(xprt);
255 wait_for_completion(&ia->ri_remove_done);
258 /* Return 1 to ensure the core destroys the id. */
260 case RDMA_CM_EVENT_ESTABLISHED:
261 ++xprt->connect_cookie;
262 ep->rep_connected = 1;
263 rpcrdma_update_cm_private(r_xprt, &event->param.conn);
264 trace_xprtrdma_inline_thresh(r_xprt);
265 wake_up_all(&ep->rep_connect_wait);
267 case RDMA_CM_EVENT_CONNECT_ERROR:
268 ep->rep_connected = -ENOTCONN;
270 case RDMA_CM_EVENT_UNREACHABLE:
271 ep->rep_connected = -ENETUNREACH;
273 case RDMA_CM_EVENT_REJECTED:
274 dprintk("rpcrdma: connection to %s:%s rejected: %s\n",
275 rpcrdma_addrstr(r_xprt), rpcrdma_portstr(r_xprt),
276 rdma_reject_msg(id, event->status));
277 ep->rep_connected = -ECONNREFUSED;
278 if (event->status == IB_CM_REJ_STALE_CONN)
279 ep->rep_connected = -EAGAIN;
281 case RDMA_CM_EVENT_DISCONNECTED:
282 ep->rep_connected = -ECONNABORTED;
284 xprt_force_disconnect(xprt);
285 wake_up_all(&ep->rep_connect_wait);
291 dprintk("RPC: %s: %s:%s on %s/frwr: %s\n", __func__,
292 rpcrdma_addrstr(r_xprt), rpcrdma_portstr(r_xprt),
293 ia->ri_id->device->name, rdma_event_msg(event->event));
297 static struct rdma_cm_id *
298 rpcrdma_create_id(struct rpcrdma_xprt *xprt, struct rpcrdma_ia *ia)
300 unsigned long wtimeout = msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT) + 1;
301 struct rdma_cm_id *id;
304 init_completion(&ia->ri_done);
306 id = rdma_create_id(xprt->rx_xprt.xprt_net, rpcrdma_cm_event_handler,
307 xprt, RDMA_PS_TCP, IB_QPT_RC);
311 ia->ri_async_rc = -ETIMEDOUT;
312 rc = rdma_resolve_addr(id, NULL,
313 (struct sockaddr *)&xprt->rx_xprt.addr,
314 RDMA_RESOLVE_TIMEOUT);
317 rc = wait_for_completion_interruptible_timeout(&ia->ri_done, wtimeout);
321 rc = ia->ri_async_rc;
325 ia->ri_async_rc = -ETIMEDOUT;
326 rc = rdma_resolve_route(id, RDMA_RESOLVE_TIMEOUT);
329 rc = wait_for_completion_interruptible_timeout(&ia->ri_done, wtimeout);
332 rc = ia->ri_async_rc;
344 * Exported functions.
348 * rpcrdma_ia_open - Open and initialize an Interface Adapter.
349 * @xprt: transport with IA to (re)initialize
351 * Returns 0 on success, negative errno if an appropriate
352 * Interface Adapter could not be found and opened.
355 rpcrdma_ia_open(struct rpcrdma_xprt *xprt)
357 struct rpcrdma_ia *ia = &xprt->rx_ia;
360 ia->ri_id = rpcrdma_create_id(xprt, ia);
361 if (IS_ERR(ia->ri_id)) {
362 rc = PTR_ERR(ia->ri_id);
366 ia->ri_pd = ib_alloc_pd(ia->ri_id->device, 0);
367 if (IS_ERR(ia->ri_pd)) {
368 rc = PTR_ERR(ia->ri_pd);
369 pr_err("rpcrdma: ib_alloc_pd() returned %d\n", rc);
376 rpcrdma_ia_close(ia);
381 * rpcrdma_ia_remove - Handle device driver unload
382 * @ia: interface adapter being removed
384 * Divest transport H/W resources associated with this adapter,
385 * but allow it to be restored later.
387 * Caller must hold the transport send lock.
390 rpcrdma_ia_remove(struct rpcrdma_ia *ia)
392 struct rpcrdma_xprt *r_xprt = container_of(ia, struct rpcrdma_xprt,
394 struct rpcrdma_ep *ep = &r_xprt->rx_ep;
396 /* This is similar to rpcrdma_ep_destroy, but:
397 * - Don't cancel the connect worker.
398 * - Don't call rpcrdma_ep_disconnect, which waits
399 * for another conn upcall, which will deadlock.
400 * - rdma_disconnect is unneeded, the underlying
401 * connection is already gone.
404 rpcrdma_xprt_drain(r_xprt);
405 rdma_destroy_qp(ia->ri_id);
406 ia->ri_id->qp = NULL;
408 ib_free_cq(ep->rep_attr.recv_cq);
409 ep->rep_attr.recv_cq = NULL;
410 ib_free_cq(ep->rep_attr.send_cq);
411 ep->rep_attr.send_cq = NULL;
413 /* The ULP is responsible for ensuring all DMA
414 * mappings and MRs are gone.
416 rpcrdma_reps_unmap(r_xprt);
417 rpcrdma_reqs_reset(r_xprt);
418 rpcrdma_mrs_destroy(r_xprt);
419 rpcrdma_sendctxs_destroy(r_xprt);
420 ib_dealloc_pd(ia->ri_pd);
423 /* Allow waiters to continue */
424 complete(&ia->ri_remove_done);
426 trace_xprtrdma_remove(r_xprt);
430 * rpcrdma_ia_close - Clean up/close an IA.
431 * @ia: interface adapter to close
435 rpcrdma_ia_close(struct rpcrdma_ia *ia)
437 if (ia->ri_id != NULL && !IS_ERR(ia->ri_id)) {
439 rdma_destroy_qp(ia->ri_id);
440 rdma_destroy_id(ia->ri_id);
444 /* If the pd is still busy, xprtrdma missed freeing a resource */
445 if (ia->ri_pd && !IS_ERR(ia->ri_pd))
446 ib_dealloc_pd(ia->ri_pd);
451 * rpcrdma_ep_create - Create unconnected endpoint
452 * @r_xprt: transport to instantiate
454 * Returns zero on success, or a negative errno.
456 int rpcrdma_ep_create(struct rpcrdma_xprt *r_xprt)
458 struct rpcrdma_ep *ep = &r_xprt->rx_ep;
459 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
460 struct rpcrdma_connect_private *pmsg = &ep->rep_cm_private;
461 struct ib_cq *sendcq, *recvcq;
464 ep->rep_max_requests = r_xprt->rx_xprt.max_reqs;
465 ep->rep_inline_send = xprt_rdma_max_inline_write;
466 ep->rep_inline_recv = xprt_rdma_max_inline_read;
468 rc = frwr_query_device(r_xprt, ia->ri_id->device);
471 r_xprt->rx_buf.rb_max_requests = cpu_to_be32(ep->rep_max_requests);
473 ep->rep_attr.event_handler = rpcrdma_qp_event_handler;
474 ep->rep_attr.qp_context = ep;
475 ep->rep_attr.srq = NULL;
476 ep->rep_attr.cap.max_inline_data = 0;
477 ep->rep_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
478 ep->rep_attr.qp_type = IB_QPT_RC;
479 ep->rep_attr.port_num = ~0;
481 dprintk("RPC: %s: requested max: dtos: send %d recv %d; "
482 "iovs: send %d recv %d\n",
484 ep->rep_attr.cap.max_send_wr,
485 ep->rep_attr.cap.max_recv_wr,
486 ep->rep_attr.cap.max_send_sge,
487 ep->rep_attr.cap.max_recv_sge);
489 ep->rep_send_batch = ep->rep_max_requests >> 3;
490 ep->rep_send_count = ep->rep_send_batch;
491 init_waitqueue_head(&ep->rep_connect_wait);
492 ep->rep_receive_count = 0;
494 sendcq = ib_alloc_cq_any(ia->ri_id->device, r_xprt,
495 ep->rep_attr.cap.max_send_wr + 1,
497 if (IS_ERR(sendcq)) {
498 rc = PTR_ERR(sendcq);
502 recvcq = ib_alloc_cq_any(ia->ri_id->device, NULL,
503 ep->rep_attr.cap.max_recv_wr + 1,
505 if (IS_ERR(recvcq)) {
506 rc = PTR_ERR(recvcq);
510 ep->rep_attr.send_cq = sendcq;
511 ep->rep_attr.recv_cq = recvcq;
513 /* Initialize cma parameters */
514 memset(&ep->rep_remote_cma, 0, sizeof(ep->rep_remote_cma));
516 /* Prepare RDMA-CM private message */
517 pmsg->cp_magic = rpcrdma_cmp_magic;
518 pmsg->cp_version = RPCRDMA_CMP_VERSION;
519 pmsg->cp_flags |= RPCRDMA_CMP_F_SND_W_INV_OK;
520 pmsg->cp_send_size = rpcrdma_encode_buffer_size(ep->rep_inline_send);
521 pmsg->cp_recv_size = rpcrdma_encode_buffer_size(ep->rep_inline_recv);
522 ep->rep_remote_cma.private_data = pmsg;
523 ep->rep_remote_cma.private_data_len = sizeof(*pmsg);
525 /* Client offers RDMA Read but does not initiate */
526 ep->rep_remote_cma.initiator_depth = 0;
527 ep->rep_remote_cma.responder_resources =
528 min_t(int, U8_MAX, ia->ri_id->device->attrs.max_qp_rd_atom);
530 /* Limit transport retries so client can detect server
531 * GID changes quickly. RPC layer handles re-establishing
532 * transport connection and retransmission.
534 ep->rep_remote_cma.retry_count = 6;
536 /* RPC-over-RDMA handles its own flow control. In addition,
537 * make all RNR NAKs visible so we know that RPC-over-RDMA
538 * flow control is working correctly (no NAKs should be seen).
540 ep->rep_remote_cma.flow_control = 0;
541 ep->rep_remote_cma.rnr_retry_count = 0;
552 * rpcrdma_ep_destroy - Disconnect and destroy endpoint.
553 * @r_xprt: transport instance to shut down
556 void rpcrdma_ep_destroy(struct rpcrdma_xprt *r_xprt)
558 struct rpcrdma_ep *ep = &r_xprt->rx_ep;
559 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
561 if (ia->ri_id && ia->ri_id->qp) {
562 rpcrdma_ep_disconnect(ep, ia);
563 rdma_destroy_qp(ia->ri_id);
564 ia->ri_id->qp = NULL;
567 if (ep->rep_attr.recv_cq)
568 ib_free_cq(ep->rep_attr.recv_cq);
569 if (ep->rep_attr.send_cq)
570 ib_free_cq(ep->rep_attr.send_cq);
573 /* Re-establish a connection after a device removal event.
574 * Unlike a normal reconnection, a fresh PD and a new set
575 * of MRs and buffers is needed.
577 static int rpcrdma_ep_recreate_xprt(struct rpcrdma_xprt *r_xprt,
578 struct ib_qp_init_attr *qp_init_attr)
580 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
581 struct rpcrdma_ep *ep = &r_xprt->rx_ep;
584 trace_xprtrdma_reinsert(r_xprt);
587 if (rpcrdma_ia_open(r_xprt))
591 err = rpcrdma_ep_create(r_xprt);
593 pr_err("rpcrdma: rpcrdma_ep_create returned %d\n", err);
596 memcpy(qp_init_attr, &ep->rep_attr, sizeof(*qp_init_attr));
599 err = rdma_create_qp(ia->ri_id, ia->ri_pd, qp_init_attr);
601 pr_err("rpcrdma: rdma_create_qp returned %d\n", err);
607 rpcrdma_ep_destroy(r_xprt);
609 rpcrdma_ia_close(ia);
614 static int rpcrdma_ep_reconnect(struct rpcrdma_xprt *r_xprt,
615 struct ib_qp_init_attr *qp_init_attr)
617 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
618 struct rdma_cm_id *id, *old;
621 rpcrdma_ep_disconnect(&r_xprt->rx_ep, ia);
624 id = rpcrdma_create_id(r_xprt, ia);
628 /* As long as the new ID points to the same device as the
629 * old ID, we can reuse the transport's existing PD and all
630 * previously allocated MRs. Also, the same device means
631 * the transport's previous DMA mappings are still valid.
633 * This is a sanity check only. There should be no way these
634 * point to two different devices here.
638 if (ia->ri_id->device != id->device) {
639 pr_err("rpcrdma: can't reconnect on different device!\n");
643 err = rdma_create_qp(id, ia->ri_pd, qp_init_attr);
647 /* Atomically replace the transport's ID and QP. */
651 rdma_destroy_qp(old);
654 rdma_destroy_id(old);
660 * Connect unconnected endpoint.
663 rpcrdma_ep_connect(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
665 struct rpcrdma_xprt *r_xprt = container_of(ia, struct rpcrdma_xprt,
667 struct rpc_xprt *xprt = &r_xprt->rx_xprt;
668 struct ib_qp_init_attr qp_init_attr;
672 memcpy(&qp_init_attr, &ep->rep_attr, sizeof(qp_init_attr));
673 switch (ep->rep_connected) {
675 rc = rdma_create_qp(ia->ri_id, ia->ri_pd, &qp_init_attr);
682 rc = rpcrdma_ep_recreate_xprt(r_xprt, &qp_init_attr);
687 rc = rpcrdma_ep_reconnect(r_xprt, &qp_init_attr);
692 ep->rep_connected = 0;
693 xprt_clear_connected(xprt);
695 rpcrdma_reset_cwnd(r_xprt);
696 rpcrdma_post_recvs(r_xprt, true);
698 rc = rpcrdma_sendctxs_create(r_xprt);
702 rc = rdma_connect(ia->ri_id, &ep->rep_remote_cma);
706 if (xprt->reestablish_timeout < RPCRDMA_INIT_REEST_TO)
707 xprt->reestablish_timeout = RPCRDMA_INIT_REEST_TO;
708 wait_event_interruptible(ep->rep_connect_wait, ep->rep_connected != 0);
709 if (ep->rep_connected <= 0) {
710 if (ep->rep_connected == -EAGAIN)
712 rc = ep->rep_connected;
716 rc = rpcrdma_reqs_setup(r_xprt);
718 rpcrdma_ep_disconnect(ep, ia);
721 rpcrdma_mrs_create(r_xprt);
725 ep->rep_connected = rc;
728 trace_xprtrdma_connect(r_xprt, rc);
733 * rpcrdma_ep_disconnect - Disconnect underlying transport
734 * @ep: endpoint to disconnect
735 * @ia: associated interface adapter
737 * Caller serializes. Either the transport send lock is held,
738 * or we're being called to destroy the transport.
741 rpcrdma_ep_disconnect(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
743 struct rpcrdma_xprt *r_xprt = container_of(ep, struct rpcrdma_xprt,
747 /* returns without wait if ID is not connected */
748 rc = rdma_disconnect(ia->ri_id);
750 wait_event_interruptible(ep->rep_connect_wait,
751 ep->rep_connected != 1);
753 ep->rep_connected = rc;
754 trace_xprtrdma_disconnect(r_xprt, rc);
756 rpcrdma_xprt_drain(r_xprt);
757 rpcrdma_reqs_reset(r_xprt);
758 rpcrdma_mrs_destroy(r_xprt);
759 rpcrdma_sendctxs_destroy(r_xprt);
762 /* Fixed-size circular FIFO queue. This implementation is wait-free and
765 * Consumer is the code path that posts Sends. This path dequeues a
766 * sendctx for use by a Send operation. Multiple consumer threads
767 * are serialized by the RPC transport lock, which allows only one
768 * ->send_request call at a time.
770 * Producer is the code path that handles Send completions. This path
771 * enqueues a sendctx that has been completed. Multiple producer
772 * threads are serialized by the ib_poll_cq() function.
775 /* rpcrdma_sendctxs_destroy() assumes caller has already quiesced
776 * queue activity, and rpcrdma_xprt_drain has flushed all remaining
779 static void rpcrdma_sendctxs_destroy(struct rpcrdma_xprt *r_xprt)
781 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
784 if (!buf->rb_sc_ctxs)
786 for (i = 0; i <= buf->rb_sc_last; i++)
787 kfree(buf->rb_sc_ctxs[i]);
788 kfree(buf->rb_sc_ctxs);
789 buf->rb_sc_ctxs = NULL;
792 static struct rpcrdma_sendctx *rpcrdma_sendctx_create(struct rpcrdma_ep *ep)
794 struct rpcrdma_sendctx *sc;
796 sc = kzalloc(struct_size(sc, sc_sges, ep->rep_attr.cap.max_send_sge),
801 sc->sc_cqe.done = rpcrdma_wc_send;
805 static int rpcrdma_sendctxs_create(struct rpcrdma_xprt *r_xprt)
807 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
808 struct rpcrdma_sendctx *sc;
811 /* Maximum number of concurrent outstanding Send WRs. Capping
812 * the circular queue size stops Send Queue overflow by causing
813 * the ->send_request call to fail temporarily before too many
816 i = r_xprt->rx_ep.rep_max_requests + RPCRDMA_MAX_BC_REQUESTS;
817 buf->rb_sc_ctxs = kcalloc(i, sizeof(sc), GFP_KERNEL);
818 if (!buf->rb_sc_ctxs)
821 buf->rb_sc_last = i - 1;
822 for (i = 0; i <= buf->rb_sc_last; i++) {
823 sc = rpcrdma_sendctx_create(&r_xprt->rx_ep);
827 buf->rb_sc_ctxs[i] = sc;
835 /* The sendctx queue is not guaranteed to have a size that is a
836 * power of two, thus the helpers in circ_buf.h cannot be used.
837 * The other option is to use modulus (%), which can be expensive.
839 static unsigned long rpcrdma_sendctx_next(struct rpcrdma_buffer *buf,
842 return likely(item < buf->rb_sc_last) ? item + 1 : 0;
846 * rpcrdma_sendctx_get_locked - Acquire a send context
847 * @r_xprt: controlling transport instance
849 * Returns pointer to a free send completion context; or NULL if
850 * the queue is empty.
852 * Usage: Called to acquire an SGE array before preparing a Send WR.
854 * The caller serializes calls to this function (per transport), and
855 * provides an effective memory barrier that flushes the new value
858 struct rpcrdma_sendctx *rpcrdma_sendctx_get_locked(struct rpcrdma_xprt *r_xprt)
860 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
861 struct rpcrdma_sendctx *sc;
862 unsigned long next_head;
864 next_head = rpcrdma_sendctx_next(buf, buf->rb_sc_head);
866 if (next_head == READ_ONCE(buf->rb_sc_tail))
869 /* ORDER: item must be accessed _before_ head is updated */
870 sc = buf->rb_sc_ctxs[next_head];
872 /* Releasing the lock in the caller acts as a memory
873 * barrier that flushes rb_sc_head.
875 buf->rb_sc_head = next_head;
880 /* The queue is "empty" if there have not been enough Send
881 * completions recently. This is a sign the Send Queue is
882 * backing up. Cause the caller to pause and try again.
884 xprt_wait_for_buffer_space(&r_xprt->rx_xprt);
885 r_xprt->rx_stats.empty_sendctx_q++;
890 * rpcrdma_sendctx_put_locked - Release a send context
891 * @r_xprt: controlling transport instance
892 * @sc: send context to release
894 * Usage: Called from Send completion to return a sendctxt
897 * The caller serializes calls to this function (per transport).
899 static void rpcrdma_sendctx_put_locked(struct rpcrdma_xprt *r_xprt,
900 struct rpcrdma_sendctx *sc)
902 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
903 unsigned long next_tail;
905 /* Unmap SGEs of previously completed but unsignaled
906 * Sends by walking up the queue until @sc is found.
908 next_tail = buf->rb_sc_tail;
910 next_tail = rpcrdma_sendctx_next(buf, next_tail);
912 /* ORDER: item must be accessed _before_ tail is updated */
913 rpcrdma_sendctx_unmap(buf->rb_sc_ctxs[next_tail]);
915 } while (buf->rb_sc_ctxs[next_tail] != sc);
917 /* Paired with READ_ONCE */
918 smp_store_release(&buf->rb_sc_tail, next_tail);
920 xprt_write_space(&r_xprt->rx_xprt);
924 rpcrdma_mrs_create(struct rpcrdma_xprt *r_xprt)
926 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
927 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
930 for (count = 0; count < ia->ri_max_rdma_segs; count++) {
931 struct rpcrdma_mr *mr;
934 mr = kzalloc(sizeof(*mr), GFP_NOFS);
938 rc = frwr_init_mr(ia, mr);
944 mr->mr_xprt = r_xprt;
946 spin_lock(&buf->rb_lock);
947 rpcrdma_mr_push(mr, &buf->rb_mrs);
948 list_add(&mr->mr_all, &buf->rb_all_mrs);
949 spin_unlock(&buf->rb_lock);
952 r_xprt->rx_stats.mrs_allocated += count;
953 trace_xprtrdma_createmrs(r_xprt, count);
957 rpcrdma_mr_refresh_worker(struct work_struct *work)
959 struct rpcrdma_buffer *buf = container_of(work, struct rpcrdma_buffer,
961 struct rpcrdma_xprt *r_xprt = container_of(buf, struct rpcrdma_xprt,
964 rpcrdma_mrs_create(r_xprt);
965 xprt_write_space(&r_xprt->rx_xprt);
969 * rpcrdma_mrs_refresh - Wake the MR refresh worker
970 * @r_xprt: controlling transport instance
973 void rpcrdma_mrs_refresh(struct rpcrdma_xprt *r_xprt)
975 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
976 struct rpcrdma_ep *ep = &r_xprt->rx_ep;
978 /* If there is no underlying device, it's no use to
979 * wake the refresh worker.
981 if (ep->rep_connected != -ENODEV) {
982 /* The work is scheduled on a WQ_MEM_RECLAIM
983 * workqueue in order to prevent MR allocation
984 * from recursing into NFS during direct reclaim.
986 queue_work(xprtiod_workqueue, &buf->rb_refresh_worker);
991 * rpcrdma_req_create - Allocate an rpcrdma_req object
992 * @r_xprt: controlling r_xprt
993 * @size: initial size, in bytes, of send and receive buffers
994 * @flags: GFP flags passed to memory allocators
996 * Returns an allocated and fully initialized rpcrdma_req or NULL.
998 struct rpcrdma_req *rpcrdma_req_create(struct rpcrdma_xprt *r_xprt, size_t size,
1001 struct rpcrdma_buffer *buffer = &r_xprt->rx_buf;
1002 struct rpcrdma_req *req;
1004 req = kzalloc(sizeof(*req), flags);
1008 req->rl_sendbuf = rpcrdma_regbuf_alloc(size, DMA_TO_DEVICE, flags);
1009 if (!req->rl_sendbuf)
1012 req->rl_recvbuf = rpcrdma_regbuf_alloc(size, DMA_NONE, flags);
1013 if (!req->rl_recvbuf)
1016 INIT_LIST_HEAD(&req->rl_free_mrs);
1017 INIT_LIST_HEAD(&req->rl_registered);
1018 spin_lock(&buffer->rb_lock);
1019 list_add(&req->rl_all, &buffer->rb_allreqs);
1020 spin_unlock(&buffer->rb_lock);
1024 kfree(req->rl_sendbuf);
1032 * rpcrdma_req_setup - Per-connection instance setup of an rpcrdma_req object
1033 * @r_xprt: controlling transport instance
1034 * @req: rpcrdma_req object to set up
1036 * Returns zero on success, and a negative errno on failure.
1038 int rpcrdma_req_setup(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req)
1040 struct rpcrdma_regbuf *rb;
1043 /* Compute maximum header buffer size in bytes */
1044 maxhdrsize = rpcrdma_fixed_maxsz + 3 +
1045 r_xprt->rx_ia.ri_max_rdma_segs * rpcrdma_readchunk_maxsz;
1046 maxhdrsize *= sizeof(__be32);
1047 rb = rpcrdma_regbuf_alloc(__roundup_pow_of_two(maxhdrsize),
1048 DMA_TO_DEVICE, GFP_KERNEL);
1052 if (!__rpcrdma_regbuf_dma_map(r_xprt, rb))
1055 req->rl_rdmabuf = rb;
1056 xdr_buf_init(&req->rl_hdrbuf, rdmab_data(rb), rdmab_length(rb));
1060 rpcrdma_regbuf_free(rb);
1065 /* ASSUMPTION: the rb_allreqs list is stable for the duration,
1066 * and thus can be walked without holding rb_lock. Eg. the
1067 * caller is holding the transport send lock to exclude
1068 * device removal or disconnection.
1070 static int rpcrdma_reqs_setup(struct rpcrdma_xprt *r_xprt)
1072 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1073 struct rpcrdma_req *req;
1076 list_for_each_entry(req, &buf->rb_allreqs, rl_all) {
1077 rc = rpcrdma_req_setup(r_xprt, req);
1084 static void rpcrdma_req_reset(struct rpcrdma_req *req)
1086 /* Credits are valid for only one connection */
1087 req->rl_slot.rq_cong = 0;
1089 rpcrdma_regbuf_free(req->rl_rdmabuf);
1090 req->rl_rdmabuf = NULL;
1092 rpcrdma_regbuf_dma_unmap(req->rl_sendbuf);
1093 rpcrdma_regbuf_dma_unmap(req->rl_recvbuf);
1096 /* ASSUMPTION: the rb_allreqs list is stable for the duration,
1097 * and thus can be walked without holding rb_lock. Eg. the
1098 * caller is holding the transport send lock to exclude
1099 * device removal or disconnection.
1101 static void rpcrdma_reqs_reset(struct rpcrdma_xprt *r_xprt)
1103 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1104 struct rpcrdma_req *req;
1106 list_for_each_entry(req, &buf->rb_allreqs, rl_all)
1107 rpcrdma_req_reset(req);
1110 /* No locking needed here. This function is called only by the
1111 * Receive completion handler.
1114 struct rpcrdma_rep *rpcrdma_rep_create(struct rpcrdma_xprt *r_xprt,
1117 struct rpcrdma_rep *rep;
1119 rep = kzalloc(sizeof(*rep), GFP_KERNEL);
1123 rep->rr_rdmabuf = rpcrdma_regbuf_alloc(r_xprt->rx_ep.rep_inline_recv,
1124 DMA_FROM_DEVICE, GFP_KERNEL);
1125 if (!rep->rr_rdmabuf)
1128 if (!rpcrdma_regbuf_dma_map(r_xprt, rep->rr_rdmabuf))
1129 goto out_free_regbuf;
1131 xdr_buf_init(&rep->rr_hdrbuf, rdmab_data(rep->rr_rdmabuf),
1132 rdmab_length(rep->rr_rdmabuf));
1133 rep->rr_cqe.done = rpcrdma_wc_receive;
1134 rep->rr_rxprt = r_xprt;
1135 rep->rr_recv_wr.next = NULL;
1136 rep->rr_recv_wr.wr_cqe = &rep->rr_cqe;
1137 rep->rr_recv_wr.sg_list = &rep->rr_rdmabuf->rg_iov;
1138 rep->rr_recv_wr.num_sge = 1;
1139 rep->rr_temp = temp;
1140 list_add(&rep->rr_all, &r_xprt->rx_buf.rb_all_reps);
1144 rpcrdma_regbuf_free(rep->rr_rdmabuf);
1151 /* No locking needed here. This function is invoked only by the
1152 * Receive completion handler, or during transport shutdown.
1154 static void rpcrdma_rep_destroy(struct rpcrdma_rep *rep)
1156 list_del(&rep->rr_all);
1157 rpcrdma_regbuf_free(rep->rr_rdmabuf);
1161 static struct rpcrdma_rep *rpcrdma_rep_get_locked(struct rpcrdma_buffer *buf)
1163 struct llist_node *node;
1165 /* Calls to llist_del_first are required to be serialized */
1166 node = llist_del_first(&buf->rb_free_reps);
1169 return llist_entry(node, struct rpcrdma_rep, rr_node);
1172 static void rpcrdma_rep_put(struct rpcrdma_buffer *buf,
1173 struct rpcrdma_rep *rep)
1175 llist_add(&rep->rr_node, &buf->rb_free_reps);
1178 static void rpcrdma_reps_unmap(struct rpcrdma_xprt *r_xprt)
1180 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1181 struct rpcrdma_rep *rep;
1183 list_for_each_entry(rep, &buf->rb_all_reps, rr_all) {
1184 rpcrdma_regbuf_dma_unmap(rep->rr_rdmabuf);
1185 rep->rr_temp = true;
1189 static void rpcrdma_reps_destroy(struct rpcrdma_buffer *buf)
1191 struct rpcrdma_rep *rep;
1193 while ((rep = rpcrdma_rep_get_locked(buf)) != NULL)
1194 rpcrdma_rep_destroy(rep);
1198 * rpcrdma_buffer_create - Create initial set of req/rep objects
1199 * @r_xprt: transport instance to (re)initialize
1201 * Returns zero on success, otherwise a negative errno.
1203 int rpcrdma_buffer_create(struct rpcrdma_xprt *r_xprt)
1205 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1208 buf->rb_bc_srv_max_requests = 0;
1209 spin_lock_init(&buf->rb_lock);
1210 INIT_LIST_HEAD(&buf->rb_mrs);
1211 INIT_LIST_HEAD(&buf->rb_all_mrs);
1212 INIT_WORK(&buf->rb_refresh_worker, rpcrdma_mr_refresh_worker);
1214 INIT_LIST_HEAD(&buf->rb_send_bufs);
1215 INIT_LIST_HEAD(&buf->rb_allreqs);
1216 INIT_LIST_HEAD(&buf->rb_all_reps);
1219 for (i = 0; i < r_xprt->rx_xprt.max_reqs; i++) {
1220 struct rpcrdma_req *req;
1222 req = rpcrdma_req_create(r_xprt, RPCRDMA_V1_DEF_INLINE_SIZE * 2,
1226 list_add(&req->rl_list, &buf->rb_send_bufs);
1229 init_llist_head(&buf->rb_free_reps);
1233 rpcrdma_buffer_destroy(buf);
1238 * rpcrdma_req_destroy - Destroy an rpcrdma_req object
1239 * @req: unused object to be destroyed
1241 * Relies on caller holding the transport send lock to protect
1242 * removing req->rl_all from buf->rb_all_reqs safely.
1244 void rpcrdma_req_destroy(struct rpcrdma_req *req)
1246 struct rpcrdma_mr *mr;
1248 list_del(&req->rl_all);
1250 while ((mr = rpcrdma_mr_pop(&req->rl_free_mrs))) {
1251 struct rpcrdma_buffer *buf = &mr->mr_xprt->rx_buf;
1253 spin_lock(&buf->rb_lock);
1254 list_del(&mr->mr_all);
1255 spin_unlock(&buf->rb_lock);
1257 frwr_release_mr(mr);
1260 rpcrdma_regbuf_free(req->rl_recvbuf);
1261 rpcrdma_regbuf_free(req->rl_sendbuf);
1262 rpcrdma_regbuf_free(req->rl_rdmabuf);
1267 * rpcrdma_mrs_destroy - Release all of a transport's MRs
1268 * @r_xprt: controlling transport instance
1270 * Relies on caller holding the transport send lock to protect
1271 * removing mr->mr_list from req->rl_free_mrs safely.
1273 static void rpcrdma_mrs_destroy(struct rpcrdma_xprt *r_xprt)
1275 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1276 struct rpcrdma_mr *mr;
1278 cancel_work_sync(&buf->rb_refresh_worker);
1280 spin_lock(&buf->rb_lock);
1281 while ((mr = list_first_entry_or_null(&buf->rb_all_mrs,
1284 list_del(&mr->mr_list);
1285 list_del(&mr->mr_all);
1286 spin_unlock(&buf->rb_lock);
1288 frwr_release_mr(mr);
1290 spin_lock(&buf->rb_lock);
1292 spin_unlock(&buf->rb_lock);
1296 * rpcrdma_buffer_destroy - Release all hw resources
1297 * @buf: root control block for resources
1299 * ORDERING: relies on a prior rpcrdma_xprt_drain :
1300 * - No more Send or Receive completions can occur
1301 * - All MRs, reps, and reqs are returned to their free lists
1304 rpcrdma_buffer_destroy(struct rpcrdma_buffer *buf)
1306 rpcrdma_reps_destroy(buf);
1308 while (!list_empty(&buf->rb_send_bufs)) {
1309 struct rpcrdma_req *req;
1311 req = list_first_entry(&buf->rb_send_bufs,
1312 struct rpcrdma_req, rl_list);
1313 list_del(&req->rl_list);
1314 rpcrdma_req_destroy(req);
1319 * rpcrdma_mr_get - Allocate an rpcrdma_mr object
1320 * @r_xprt: controlling transport
1322 * Returns an initialized rpcrdma_mr or NULL if no free
1323 * rpcrdma_mr objects are available.
1326 rpcrdma_mr_get(struct rpcrdma_xprt *r_xprt)
1328 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1329 struct rpcrdma_mr *mr;
1331 spin_lock(&buf->rb_lock);
1332 mr = rpcrdma_mr_pop(&buf->rb_mrs);
1333 spin_unlock(&buf->rb_lock);
1338 * rpcrdma_mr_put - DMA unmap an MR and release it
1339 * @mr: MR to release
1342 void rpcrdma_mr_put(struct rpcrdma_mr *mr)
1344 struct rpcrdma_xprt *r_xprt = mr->mr_xprt;
1346 if (mr->mr_dir != DMA_NONE) {
1347 trace_xprtrdma_mr_unmap(mr);
1348 ib_dma_unmap_sg(r_xprt->rx_ia.ri_id->device,
1349 mr->mr_sg, mr->mr_nents, mr->mr_dir);
1350 mr->mr_dir = DMA_NONE;
1353 rpcrdma_mr_push(mr, &mr->mr_req->rl_free_mrs);
1357 * rpcrdma_buffer_get - Get a request buffer
1358 * @buffers: Buffer pool from which to obtain a buffer
1360 * Returns a fresh rpcrdma_req, or NULL if none are available.
1362 struct rpcrdma_req *
1363 rpcrdma_buffer_get(struct rpcrdma_buffer *buffers)
1365 struct rpcrdma_req *req;
1367 spin_lock(&buffers->rb_lock);
1368 req = list_first_entry_or_null(&buffers->rb_send_bufs,
1369 struct rpcrdma_req, rl_list);
1371 list_del_init(&req->rl_list);
1372 spin_unlock(&buffers->rb_lock);
1377 * rpcrdma_buffer_put - Put request/reply buffers back into pool
1378 * @buffers: buffer pool
1379 * @req: object to return
1382 void rpcrdma_buffer_put(struct rpcrdma_buffer *buffers, struct rpcrdma_req *req)
1385 rpcrdma_rep_put(buffers, req->rl_reply);
1386 req->rl_reply = NULL;
1388 spin_lock(&buffers->rb_lock);
1389 list_add(&req->rl_list, &buffers->rb_send_bufs);
1390 spin_unlock(&buffers->rb_lock);
1394 * rpcrdma_recv_buffer_put - Release rpcrdma_rep back to free list
1395 * @rep: rep to release
1397 * Used after error conditions.
1399 void rpcrdma_recv_buffer_put(struct rpcrdma_rep *rep)
1401 rpcrdma_rep_put(&rep->rr_rxprt->rx_buf, rep);
1404 /* Returns a pointer to a rpcrdma_regbuf object, or NULL.
1406 * xprtrdma uses a regbuf for posting an outgoing RDMA SEND, or for
1407 * receiving the payload of RDMA RECV operations. During Long Calls
1408 * or Replies they may be registered externally via frwr_map.
1410 static struct rpcrdma_regbuf *
1411 rpcrdma_regbuf_alloc(size_t size, enum dma_data_direction direction,
1414 struct rpcrdma_regbuf *rb;
1416 rb = kmalloc(sizeof(*rb), flags);
1419 rb->rg_data = kmalloc(size, flags);
1425 rb->rg_device = NULL;
1426 rb->rg_direction = direction;
1427 rb->rg_iov.length = size;
1432 * rpcrdma_regbuf_realloc - re-allocate a SEND/RECV buffer
1433 * @rb: regbuf to reallocate
1434 * @size: size of buffer to be allocated, in bytes
1437 * Returns true if reallocation was successful. If false is
1438 * returned, @rb is left untouched.
1440 bool rpcrdma_regbuf_realloc(struct rpcrdma_regbuf *rb, size_t size, gfp_t flags)
1444 buf = kmalloc(size, flags);
1448 rpcrdma_regbuf_dma_unmap(rb);
1452 rb->rg_iov.length = size;
1457 * __rpcrdma_regbuf_dma_map - DMA-map a regbuf
1458 * @r_xprt: controlling transport instance
1459 * @rb: regbuf to be mapped
1461 * Returns true if the buffer is now DMA mapped to @r_xprt's device
1463 bool __rpcrdma_regbuf_dma_map(struct rpcrdma_xprt *r_xprt,
1464 struct rpcrdma_regbuf *rb)
1466 struct ib_device *device = r_xprt->rx_ia.ri_id->device;
1468 if (rb->rg_direction == DMA_NONE)
1471 rb->rg_iov.addr = ib_dma_map_single(device, rdmab_data(rb),
1472 rdmab_length(rb), rb->rg_direction);
1473 if (ib_dma_mapping_error(device, rdmab_addr(rb))) {
1474 trace_xprtrdma_dma_maperr(rdmab_addr(rb));
1478 rb->rg_device = device;
1479 rb->rg_iov.lkey = r_xprt->rx_ia.ri_pd->local_dma_lkey;
1483 static void rpcrdma_regbuf_dma_unmap(struct rpcrdma_regbuf *rb)
1488 if (!rpcrdma_regbuf_is_mapped(rb))
1491 ib_dma_unmap_single(rb->rg_device, rdmab_addr(rb), rdmab_length(rb),
1493 rb->rg_device = NULL;
1496 static void rpcrdma_regbuf_free(struct rpcrdma_regbuf *rb)
1498 rpcrdma_regbuf_dma_unmap(rb);
1505 * rpcrdma_ep_post - Post WRs to a transport's Send Queue
1506 * @ia: transport's device information
1507 * @ep: transport's RDMA endpoint information
1508 * @req: rpcrdma_req containing the Send WR to post
1510 * Returns 0 if the post was successful, otherwise -ENOTCONN
1514 rpcrdma_ep_post(struct rpcrdma_ia *ia,
1515 struct rpcrdma_ep *ep,
1516 struct rpcrdma_req *req)
1518 struct ib_send_wr *send_wr = &req->rl_wr;
1521 if (!ep->rep_send_count || kref_read(&req->rl_kref) > 1) {
1522 send_wr->send_flags |= IB_SEND_SIGNALED;
1523 ep->rep_send_count = ep->rep_send_batch;
1525 send_wr->send_flags &= ~IB_SEND_SIGNALED;
1526 --ep->rep_send_count;
1529 rc = frwr_send(ia, req);
1530 trace_xprtrdma_post_send(req, rc);
1537 * rpcrdma_post_recvs - Refill the Receive Queue
1538 * @r_xprt: controlling transport instance
1539 * @temp: mark Receive buffers to be deleted after use
1542 void rpcrdma_post_recvs(struct rpcrdma_xprt *r_xprt, bool temp)
1544 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1545 struct rpcrdma_ep *ep = &r_xprt->rx_ep;
1546 struct ib_recv_wr *wr, *bad_wr;
1547 struct rpcrdma_rep *rep;
1548 int needed, count, rc;
1553 needed = buf->rb_credits + (buf->rb_bc_srv_max_requests << 1);
1554 if (likely(ep->rep_receive_count > needed))
1556 needed -= ep->rep_receive_count;
1558 needed += RPCRDMA_MAX_RECV_BATCH;
1560 /* fast path: all needed reps can be found on the free list */
1563 rep = rpcrdma_rep_get_locked(buf);
1564 if (rep && rep->rr_temp) {
1565 rpcrdma_rep_destroy(rep);
1569 rep = rpcrdma_rep_create(r_xprt, temp);
1573 trace_xprtrdma_post_recv(rep);
1574 rep->rr_recv_wr.next = wr;
1575 wr = &rep->rr_recv_wr;
1582 rc = ib_post_recv(r_xprt->rx_ia.ri_id->qp, wr,
1583 (const struct ib_recv_wr **)&bad_wr);
1585 trace_xprtrdma_post_recvs(r_xprt, count, rc);
1587 for (wr = bad_wr; wr;) {
1588 struct rpcrdma_rep *rep;
1590 rep = container_of(wr, struct rpcrdma_rep, rr_recv_wr);
1592 rpcrdma_recv_buffer_put(rep);
1596 ep->rep_receive_count += count;