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.
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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
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34 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
35 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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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 void rpcrdma_sendctx_put_locked(struct rpcrdma_xprt *r_xprt,
78 struct rpcrdma_sendctx *sc);
79 static void rpcrdma_reqs_reset(struct rpcrdma_xprt *r_xprt);
80 static void rpcrdma_reps_destroy(struct rpcrdma_buffer *buf);
81 static void rpcrdma_mrs_create(struct rpcrdma_xprt *r_xprt);
82 static void rpcrdma_mrs_destroy(struct rpcrdma_xprt *r_xprt);
83 static struct rpcrdma_regbuf *
84 rpcrdma_regbuf_alloc(size_t size, enum dma_data_direction direction,
86 static void rpcrdma_regbuf_dma_unmap(struct rpcrdma_regbuf *rb);
87 static void rpcrdma_regbuf_free(struct rpcrdma_regbuf *rb);
89 /* Wait for outstanding transport work to finish. ib_drain_qp
90 * handles the drains in the wrong order for us, so open code
93 static void rpcrdma_xprt_drain(struct rpcrdma_xprt *r_xprt)
95 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
97 /* Flush Receives, then wait for deferred Reply work
100 ib_drain_rq(ia->ri_id->qp);
102 /* Deferred Reply processing might have scheduled
103 * local invalidations.
105 ib_drain_sq(ia->ri_id->qp);
109 * rpcrdma_qp_event_handler - Handle one QP event (error notification)
110 * @event: details of the event
111 * @context: ep that owns QP where event occurred
113 * Called from the RDMA provider (device driver) possibly in an interrupt
117 rpcrdma_qp_event_handler(struct ib_event *event, void *context)
119 struct rpcrdma_ep *ep = context;
120 struct rpcrdma_xprt *r_xprt = container_of(ep, struct rpcrdma_xprt,
123 trace_xprtrdma_qp_event(r_xprt, event);
127 * rpcrdma_wc_send - Invoked by RDMA provider for each polled Send WC
128 * @cq: completion queue
133 rpcrdma_wc_send(struct ib_cq *cq, struct ib_wc *wc)
135 struct ib_cqe *cqe = wc->wr_cqe;
136 struct rpcrdma_sendctx *sc =
137 container_of(cqe, struct rpcrdma_sendctx, sc_cqe);
139 /* WARNING: Only wr_cqe and status are reliable at this point */
140 trace_xprtrdma_wc_send(sc, wc);
141 rpcrdma_sendctx_put_locked((struct rpcrdma_xprt *)cq->cq_context, sc);
145 * rpcrdma_wc_receive - Invoked by RDMA provider for each polled Receive WC
146 * @cq: completion queue (ignored)
151 rpcrdma_wc_receive(struct ib_cq *cq, struct ib_wc *wc)
153 struct ib_cqe *cqe = wc->wr_cqe;
154 struct rpcrdma_rep *rep = container_of(cqe, struct rpcrdma_rep,
156 struct rpcrdma_xprt *r_xprt = rep->rr_rxprt;
158 /* WARNING: Only wr_cqe and status are reliable at this point */
159 trace_xprtrdma_wc_receive(wc);
160 --r_xprt->rx_ep.rep_receive_count;
161 if (wc->status != IB_WC_SUCCESS)
164 /* status == SUCCESS means all fields in wc are trustworthy */
165 rpcrdma_set_xdrlen(&rep->rr_hdrbuf, wc->byte_len);
166 rep->rr_wc_flags = wc->wc_flags;
167 rep->rr_inv_rkey = wc->ex.invalidate_rkey;
169 ib_dma_sync_single_for_cpu(rdmab_device(rep->rr_rdmabuf),
170 rdmab_addr(rep->rr_rdmabuf),
171 wc->byte_len, DMA_FROM_DEVICE);
173 rpcrdma_reply_handler(rep);
177 rpcrdma_recv_buffer_put(rep);
180 static void rpcrdma_update_cm_private(struct rpcrdma_xprt *r_xprt,
181 struct rdma_conn_param *param)
183 const struct rpcrdma_connect_private *pmsg = param->private_data;
184 struct rpcrdma_ep *ep = &r_xprt->rx_ep;
185 unsigned int rsize, wsize;
187 /* Default settings for RPC-over-RDMA Version One */
188 r_xprt->rx_ia.ri_implicit_roundup = xprt_rdma_pad_optimize;
189 rsize = RPCRDMA_V1_DEF_INLINE_SIZE;
190 wsize = RPCRDMA_V1_DEF_INLINE_SIZE;
193 pmsg->cp_magic == rpcrdma_cmp_magic &&
194 pmsg->cp_version == RPCRDMA_CMP_VERSION) {
195 r_xprt->rx_ia.ri_implicit_roundup = true;
196 rsize = rpcrdma_decode_buffer_size(pmsg->cp_send_size);
197 wsize = rpcrdma_decode_buffer_size(pmsg->cp_recv_size);
200 if (rsize < ep->rep_inline_recv)
201 ep->rep_inline_recv = rsize;
202 if (wsize < ep->rep_inline_send)
203 ep->rep_inline_send = wsize;
205 rpcrdma_set_max_header_sizes(r_xprt);
209 * rpcrdma_cm_event_handler - Handle RDMA CM events
210 * @id: rdma_cm_id on which an event has occurred
211 * @event: details of the event
213 * Called with @id's mutex held. Returns 1 if caller should
214 * destroy @id, otherwise 0.
217 rpcrdma_cm_event_handler(struct rdma_cm_id *id, struct rdma_cm_event *event)
219 struct rpcrdma_xprt *r_xprt = id->context;
220 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
221 struct rpcrdma_ep *ep = &r_xprt->rx_ep;
222 struct rpc_xprt *xprt = &r_xprt->rx_xprt;
226 trace_xprtrdma_cm_event(r_xprt, event);
227 switch (event->event) {
228 case RDMA_CM_EVENT_ADDR_RESOLVED:
229 case RDMA_CM_EVENT_ROUTE_RESOLVED:
231 complete(&ia->ri_done);
233 case RDMA_CM_EVENT_ADDR_ERROR:
234 ia->ri_async_rc = -EPROTO;
235 complete(&ia->ri_done);
237 case RDMA_CM_EVENT_ROUTE_ERROR:
238 ia->ri_async_rc = -ENETUNREACH;
239 complete(&ia->ri_done);
241 case RDMA_CM_EVENT_DEVICE_REMOVAL:
242 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
243 pr_info("rpcrdma: removing device %s for %s:%s\n",
244 ia->ri_id->device->name,
245 rpcrdma_addrstr(r_xprt), rpcrdma_portstr(r_xprt));
247 set_bit(RPCRDMA_IAF_REMOVING, &ia->ri_flags);
248 ep->rep_connected = -ENODEV;
249 xprt_force_disconnect(xprt);
250 wait_for_completion(&ia->ri_remove_done);
253 /* Return 1 to ensure the core destroys the id. */
255 case RDMA_CM_EVENT_ESTABLISHED:
256 ++xprt->connect_cookie;
257 ep->rep_connected = 1;
258 rpcrdma_update_cm_private(r_xprt, &event->param.conn);
259 trace_xprtrdma_inline_thresh(r_xprt);
260 wake_up_all(&ep->rep_connect_wait);
262 case RDMA_CM_EVENT_CONNECT_ERROR:
263 ep->rep_connected = -ENOTCONN;
265 case RDMA_CM_EVENT_UNREACHABLE:
266 ep->rep_connected = -ENETUNREACH;
268 case RDMA_CM_EVENT_REJECTED:
269 dprintk("rpcrdma: connection to %s:%s rejected: %s\n",
270 rpcrdma_addrstr(r_xprt), rpcrdma_portstr(r_xprt),
271 rdma_reject_msg(id, event->status));
272 ep->rep_connected = -ECONNREFUSED;
273 if (event->status == IB_CM_REJ_STALE_CONN)
274 ep->rep_connected = -EAGAIN;
276 case RDMA_CM_EVENT_DISCONNECTED:
277 ep->rep_connected = -ECONNABORTED;
279 xprt_force_disconnect(xprt);
280 wake_up_all(&ep->rep_connect_wait);
286 dprintk("RPC: %s: %s:%s on %s/frwr: %s\n", __func__,
287 rpcrdma_addrstr(r_xprt), rpcrdma_portstr(r_xprt),
288 ia->ri_id->device->name, rdma_event_msg(event->event));
292 static struct rdma_cm_id *
293 rpcrdma_create_id(struct rpcrdma_xprt *xprt, struct rpcrdma_ia *ia)
295 unsigned long wtimeout = msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT) + 1;
296 struct rdma_cm_id *id;
299 init_completion(&ia->ri_done);
300 init_completion(&ia->ri_remove_done);
302 id = rdma_create_id(xprt->rx_xprt.xprt_net, rpcrdma_cm_event_handler,
303 xprt, RDMA_PS_TCP, IB_QPT_RC);
307 ia->ri_async_rc = -ETIMEDOUT;
308 rc = rdma_resolve_addr(id, NULL,
309 (struct sockaddr *)&xprt->rx_xprt.addr,
310 RDMA_RESOLVE_TIMEOUT);
313 rc = wait_for_completion_interruptible_timeout(&ia->ri_done, wtimeout);
317 rc = ia->ri_async_rc;
321 ia->ri_async_rc = -ETIMEDOUT;
322 rc = rdma_resolve_route(id, RDMA_RESOLVE_TIMEOUT);
325 rc = wait_for_completion_interruptible_timeout(&ia->ri_done, wtimeout);
328 rc = ia->ri_async_rc;
340 * Exported functions.
344 * rpcrdma_ia_open - Open and initialize an Interface Adapter.
345 * @xprt: transport with IA to (re)initialize
347 * Returns 0 on success, negative errno if an appropriate
348 * Interface Adapter could not be found and opened.
351 rpcrdma_ia_open(struct rpcrdma_xprt *xprt)
353 struct rpcrdma_ia *ia = &xprt->rx_ia;
356 ia->ri_id = rpcrdma_create_id(xprt, ia);
357 if (IS_ERR(ia->ri_id)) {
358 rc = PTR_ERR(ia->ri_id);
362 ia->ri_pd = ib_alloc_pd(ia->ri_id->device, 0);
363 if (IS_ERR(ia->ri_pd)) {
364 rc = PTR_ERR(ia->ri_pd);
365 pr_err("rpcrdma: ib_alloc_pd() returned %d\n", rc);
369 switch (xprt_rdma_memreg_strategy) {
371 if (frwr_is_supported(ia->ri_id->device))
375 pr_err("rpcrdma: Device %s does not support memreg mode %d\n",
376 ia->ri_id->device->name, xprt_rdma_memreg_strategy);
384 rpcrdma_ia_close(ia);
389 * rpcrdma_ia_remove - Handle device driver unload
390 * @ia: interface adapter being removed
392 * Divest transport H/W resources associated with this adapter,
393 * but allow it to be restored later.
396 rpcrdma_ia_remove(struct rpcrdma_ia *ia)
398 struct rpcrdma_xprt *r_xprt = container_of(ia, struct rpcrdma_xprt,
400 struct rpcrdma_ep *ep = &r_xprt->rx_ep;
401 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
402 struct rpcrdma_req *req;
404 /* This is similar to rpcrdma_ep_destroy, but:
405 * - Don't cancel the connect worker.
406 * - Don't call rpcrdma_ep_disconnect, which waits
407 * for another conn upcall, which will deadlock.
408 * - rdma_disconnect is unneeded, the underlying
409 * connection is already gone.
412 rpcrdma_xprt_drain(r_xprt);
413 rdma_destroy_qp(ia->ri_id);
414 ia->ri_id->qp = NULL;
416 ib_free_cq(ep->rep_attr.recv_cq);
417 ep->rep_attr.recv_cq = NULL;
418 ib_free_cq(ep->rep_attr.send_cq);
419 ep->rep_attr.send_cq = NULL;
421 /* The ULP is responsible for ensuring all DMA
422 * mappings and MRs are gone.
424 rpcrdma_reps_destroy(buf);
425 list_for_each_entry(req, &buf->rb_allreqs, rl_all) {
426 rpcrdma_regbuf_dma_unmap(req->rl_rdmabuf);
427 rpcrdma_regbuf_dma_unmap(req->rl_sendbuf);
428 rpcrdma_regbuf_dma_unmap(req->rl_recvbuf);
430 rpcrdma_mrs_destroy(r_xprt);
431 ib_dealloc_pd(ia->ri_pd);
434 /* Allow waiters to continue */
435 complete(&ia->ri_remove_done);
437 trace_xprtrdma_remove(r_xprt);
441 * rpcrdma_ia_close - Clean up/close an IA.
442 * @ia: interface adapter to close
446 rpcrdma_ia_close(struct rpcrdma_ia *ia)
448 if (ia->ri_id != NULL && !IS_ERR(ia->ri_id)) {
450 rdma_destroy_qp(ia->ri_id);
451 rdma_destroy_id(ia->ri_id);
455 /* If the pd is still busy, xprtrdma missed freeing a resource */
456 if (ia->ri_pd && !IS_ERR(ia->ri_pd))
457 ib_dealloc_pd(ia->ri_pd);
462 * rpcrdma_ep_create - Create unconnected endpoint
463 * @r_xprt: transport to instantiate
465 * Returns zero on success, or a negative errno.
467 int rpcrdma_ep_create(struct rpcrdma_xprt *r_xprt)
469 struct rpcrdma_ep *ep = &r_xprt->rx_ep;
470 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
471 struct rpcrdma_connect_private *pmsg = &ep->rep_cm_private;
472 struct ib_cq *sendcq, *recvcq;
473 unsigned int max_sge;
476 ep->rep_max_requests = xprt_rdma_slot_table_entries;
477 ep->rep_inline_send = xprt_rdma_max_inline_write;
478 ep->rep_inline_recv = xprt_rdma_max_inline_read;
480 max_sge = min_t(unsigned int, ia->ri_id->device->attrs.max_send_sge,
481 RPCRDMA_MAX_SEND_SGES);
482 if (max_sge < RPCRDMA_MIN_SEND_SGES) {
483 pr_warn("rpcrdma: HCA provides only %d send SGEs\n", max_sge);
486 ia->ri_max_send_sges = max_sge;
488 rc = frwr_open(ia, ep);
492 ep->rep_attr.event_handler = rpcrdma_qp_event_handler;
493 ep->rep_attr.qp_context = ep;
494 ep->rep_attr.srq = NULL;
495 ep->rep_attr.cap.max_send_sge = max_sge;
496 ep->rep_attr.cap.max_recv_sge = 1;
497 ep->rep_attr.cap.max_inline_data = 0;
498 ep->rep_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
499 ep->rep_attr.qp_type = IB_QPT_RC;
500 ep->rep_attr.port_num = ~0;
502 dprintk("RPC: %s: requested max: dtos: send %d recv %d; "
503 "iovs: send %d recv %d\n",
505 ep->rep_attr.cap.max_send_wr,
506 ep->rep_attr.cap.max_recv_wr,
507 ep->rep_attr.cap.max_send_sge,
508 ep->rep_attr.cap.max_recv_sge);
510 ep->rep_send_batch = ep->rep_max_requests >> 3;
511 ep->rep_send_count = ep->rep_send_batch;
512 init_waitqueue_head(&ep->rep_connect_wait);
513 ep->rep_receive_count = 0;
515 sendcq = ib_alloc_cq_any(ia->ri_id->device, r_xprt,
516 ep->rep_attr.cap.max_send_wr + 1,
518 if (IS_ERR(sendcq)) {
519 rc = PTR_ERR(sendcq);
523 recvcq = ib_alloc_cq_any(ia->ri_id->device, NULL,
524 ep->rep_attr.cap.max_recv_wr + 1,
526 if (IS_ERR(recvcq)) {
527 rc = PTR_ERR(recvcq);
531 ep->rep_attr.send_cq = sendcq;
532 ep->rep_attr.recv_cq = recvcq;
534 /* Initialize cma parameters */
535 memset(&ep->rep_remote_cma, 0, sizeof(ep->rep_remote_cma));
537 /* Prepare RDMA-CM private message */
538 pmsg->cp_magic = rpcrdma_cmp_magic;
539 pmsg->cp_version = RPCRDMA_CMP_VERSION;
540 pmsg->cp_flags |= RPCRDMA_CMP_F_SND_W_INV_OK;
541 pmsg->cp_send_size = rpcrdma_encode_buffer_size(ep->rep_inline_send);
542 pmsg->cp_recv_size = rpcrdma_encode_buffer_size(ep->rep_inline_recv);
543 ep->rep_remote_cma.private_data = pmsg;
544 ep->rep_remote_cma.private_data_len = sizeof(*pmsg);
546 /* Client offers RDMA Read but does not initiate */
547 ep->rep_remote_cma.initiator_depth = 0;
548 ep->rep_remote_cma.responder_resources =
549 min_t(int, U8_MAX, ia->ri_id->device->attrs.max_qp_rd_atom);
551 /* Limit transport retries so client can detect server
552 * GID changes quickly. RPC layer handles re-establishing
553 * transport connection and retransmission.
555 ep->rep_remote_cma.retry_count = 6;
557 /* RPC-over-RDMA handles its own flow control. In addition,
558 * make all RNR NAKs visible so we know that RPC-over-RDMA
559 * flow control is working correctly (no NAKs should be seen).
561 ep->rep_remote_cma.flow_control = 0;
562 ep->rep_remote_cma.rnr_retry_count = 0;
573 * rpcrdma_ep_destroy - Disconnect and destroy endpoint.
574 * @r_xprt: transport instance to shut down
577 void rpcrdma_ep_destroy(struct rpcrdma_xprt *r_xprt)
579 struct rpcrdma_ep *ep = &r_xprt->rx_ep;
580 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
582 if (ia->ri_id && ia->ri_id->qp) {
583 rpcrdma_ep_disconnect(ep, ia);
584 rdma_destroy_qp(ia->ri_id);
585 ia->ri_id->qp = NULL;
588 if (ep->rep_attr.recv_cq)
589 ib_free_cq(ep->rep_attr.recv_cq);
590 if (ep->rep_attr.send_cq)
591 ib_free_cq(ep->rep_attr.send_cq);
594 /* Re-establish a connection after a device removal event.
595 * Unlike a normal reconnection, a fresh PD and a new set
596 * of MRs and buffers is needed.
598 static int rpcrdma_ep_recreate_xprt(struct rpcrdma_xprt *r_xprt,
599 struct ib_qp_init_attr *qp_init_attr)
601 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
604 trace_xprtrdma_reinsert(r_xprt);
607 if (rpcrdma_ia_open(r_xprt))
611 err = rpcrdma_ep_create(r_xprt);
613 pr_err("rpcrdma: rpcrdma_ep_create returned %d\n", err);
618 err = rdma_create_qp(ia->ri_id, ia->ri_pd, qp_init_attr);
620 pr_err("rpcrdma: rdma_create_qp returned %d\n", err);
626 rpcrdma_ep_destroy(r_xprt);
628 rpcrdma_ia_close(ia);
633 static int rpcrdma_ep_reconnect(struct rpcrdma_xprt *r_xprt,
634 struct ib_qp_init_attr *qp_init_attr)
636 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
637 struct rdma_cm_id *id, *old;
640 rpcrdma_ep_disconnect(&r_xprt->rx_ep, ia);
643 id = rpcrdma_create_id(r_xprt, ia);
647 /* As long as the new ID points to the same device as the
648 * old ID, we can reuse the transport's existing PD and all
649 * previously allocated MRs. Also, the same device means
650 * the transport's previous DMA mappings are still valid.
652 * This is a sanity check only. There should be no way these
653 * point to two different devices here.
657 if (ia->ri_id->device != id->device) {
658 pr_err("rpcrdma: can't reconnect on different device!\n");
662 err = rdma_create_qp(id, ia->ri_pd, qp_init_attr);
666 /* Atomically replace the transport's ID and QP. */
670 rdma_destroy_qp(old);
673 rdma_destroy_id(old);
679 * Connect unconnected endpoint.
682 rpcrdma_ep_connect(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
684 struct rpcrdma_xprt *r_xprt = container_of(ia, struct rpcrdma_xprt,
686 struct rpc_xprt *xprt = &r_xprt->rx_xprt;
687 struct ib_qp_init_attr qp_init_attr;
691 memcpy(&qp_init_attr, &ep->rep_attr, sizeof(qp_init_attr));
692 switch (ep->rep_connected) {
694 rc = rdma_create_qp(ia->ri_id, ia->ri_pd, &qp_init_attr);
701 rc = rpcrdma_ep_recreate_xprt(r_xprt, &qp_init_attr);
706 rc = rpcrdma_ep_reconnect(r_xprt, &qp_init_attr);
711 ep->rep_connected = 0;
712 xprt_clear_connected(xprt);
714 rpcrdma_reset_cwnd(r_xprt);
715 rpcrdma_post_recvs(r_xprt, true);
717 rc = rdma_connect(ia->ri_id, &ep->rep_remote_cma);
721 if (xprt->reestablish_timeout < RPCRDMA_INIT_REEST_TO)
722 xprt->reestablish_timeout = RPCRDMA_INIT_REEST_TO;
723 wait_event_interruptible(ep->rep_connect_wait, ep->rep_connected != 0);
724 if (ep->rep_connected <= 0) {
725 if (ep->rep_connected == -EAGAIN)
727 rc = ep->rep_connected;
731 rpcrdma_mrs_create(r_xprt);
735 ep->rep_connected = rc;
738 trace_xprtrdma_connect(r_xprt, rc);
743 * rpcrdma_ep_disconnect - Disconnect underlying transport
744 * @ep: endpoint to disconnect
745 * @ia: associated interface adapter
747 * Caller serializes. Either the transport send lock is held,
748 * or we're being called to destroy the transport.
751 rpcrdma_ep_disconnect(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
753 struct rpcrdma_xprt *r_xprt = container_of(ep, struct rpcrdma_xprt,
757 /* returns without wait if ID is not connected */
758 rc = rdma_disconnect(ia->ri_id);
760 wait_event_interruptible(ep->rep_connect_wait,
761 ep->rep_connected != 1);
763 ep->rep_connected = rc;
764 trace_xprtrdma_disconnect(r_xprt, rc);
766 rpcrdma_xprt_drain(r_xprt);
767 rpcrdma_reqs_reset(r_xprt);
768 rpcrdma_mrs_destroy(r_xprt);
771 /* Fixed-size circular FIFO queue. This implementation is wait-free and
774 * Consumer is the code path that posts Sends. This path dequeues a
775 * sendctx for use by a Send operation. Multiple consumer threads
776 * are serialized by the RPC transport lock, which allows only one
777 * ->send_request call at a time.
779 * Producer is the code path that handles Send completions. This path
780 * enqueues a sendctx that has been completed. Multiple producer
781 * threads are serialized by the ib_poll_cq() function.
784 /* rpcrdma_sendctxs_destroy() assumes caller has already quiesced
785 * queue activity, and rpcrdma_xprt_drain has flushed all remaining
788 static void rpcrdma_sendctxs_destroy(struct rpcrdma_buffer *buf)
792 for (i = 0; i <= buf->rb_sc_last; i++)
793 kfree(buf->rb_sc_ctxs[i]);
794 kfree(buf->rb_sc_ctxs);
797 static struct rpcrdma_sendctx *rpcrdma_sendctx_create(struct rpcrdma_ia *ia)
799 struct rpcrdma_sendctx *sc;
801 sc = kzalloc(struct_size(sc, sc_sges, ia->ri_max_send_sges),
806 sc->sc_cqe.done = rpcrdma_wc_send;
810 static int rpcrdma_sendctxs_create(struct rpcrdma_xprt *r_xprt)
812 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
813 struct rpcrdma_sendctx *sc;
816 /* Maximum number of concurrent outstanding Send WRs. Capping
817 * the circular queue size stops Send Queue overflow by causing
818 * the ->send_request call to fail temporarily before too many
821 i = buf->rb_max_requests + RPCRDMA_MAX_BC_REQUESTS;
822 dprintk("RPC: %s: allocating %lu send_ctxs\n", __func__, i);
823 buf->rb_sc_ctxs = kcalloc(i, sizeof(sc), GFP_KERNEL);
824 if (!buf->rb_sc_ctxs)
827 buf->rb_sc_last = i - 1;
828 for (i = 0; i <= buf->rb_sc_last; i++) {
829 sc = rpcrdma_sendctx_create(&r_xprt->rx_ia);
833 buf->rb_sc_ctxs[i] = sc;
839 /* The sendctx queue is not guaranteed to have a size that is a
840 * power of two, thus the helpers in circ_buf.h cannot be used.
841 * The other option is to use modulus (%), which can be expensive.
843 static unsigned long rpcrdma_sendctx_next(struct rpcrdma_buffer *buf,
846 return likely(item < buf->rb_sc_last) ? item + 1 : 0;
850 * rpcrdma_sendctx_get_locked - Acquire a send context
851 * @r_xprt: controlling transport instance
853 * Returns pointer to a free send completion context; or NULL if
854 * the queue is empty.
856 * Usage: Called to acquire an SGE array before preparing a Send WR.
858 * The caller serializes calls to this function (per transport), and
859 * provides an effective memory barrier that flushes the new value
862 struct rpcrdma_sendctx *rpcrdma_sendctx_get_locked(struct rpcrdma_xprt *r_xprt)
864 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
865 struct rpcrdma_sendctx *sc;
866 unsigned long next_head;
868 next_head = rpcrdma_sendctx_next(buf, buf->rb_sc_head);
870 if (next_head == READ_ONCE(buf->rb_sc_tail))
873 /* ORDER: item must be accessed _before_ head is updated */
874 sc = buf->rb_sc_ctxs[next_head];
876 /* Releasing the lock in the caller acts as a memory
877 * barrier that flushes rb_sc_head.
879 buf->rb_sc_head = next_head;
884 /* The queue is "empty" if there have not been enough Send
885 * completions recently. This is a sign the Send Queue is
886 * backing up. Cause the caller to pause and try again.
888 xprt_wait_for_buffer_space(&r_xprt->rx_xprt);
889 r_xprt->rx_stats.empty_sendctx_q++;
894 * rpcrdma_sendctx_put_locked - Release a send context
895 * @r_xprt: controlling transport instance
896 * @sc: send context to release
898 * Usage: Called from Send completion to return a sendctxt
901 * The caller serializes calls to this function (per transport).
903 static void rpcrdma_sendctx_put_locked(struct rpcrdma_xprt *r_xprt,
904 struct rpcrdma_sendctx *sc)
906 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
907 unsigned long next_tail;
909 /* Unmap SGEs of previously completed but unsignaled
910 * Sends by walking up the queue until @sc is found.
912 next_tail = buf->rb_sc_tail;
914 next_tail = rpcrdma_sendctx_next(buf, next_tail);
916 /* ORDER: item must be accessed _before_ tail is updated */
917 rpcrdma_sendctx_unmap(buf->rb_sc_ctxs[next_tail]);
919 } while (buf->rb_sc_ctxs[next_tail] != sc);
921 /* Paired with READ_ONCE */
922 smp_store_release(&buf->rb_sc_tail, next_tail);
924 xprt_write_space(&r_xprt->rx_xprt);
928 rpcrdma_mrs_create(struct rpcrdma_xprt *r_xprt)
930 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
931 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
934 for (count = 0; count < ia->ri_max_segs; count++) {
935 struct rpcrdma_mr *mr;
938 mr = kzalloc(sizeof(*mr), GFP_NOFS);
942 rc = frwr_init_mr(ia, mr);
948 mr->mr_xprt = r_xprt;
950 spin_lock(&buf->rb_lock);
951 rpcrdma_mr_push(mr, &buf->rb_mrs);
952 list_add(&mr->mr_all, &buf->rb_all_mrs);
953 spin_unlock(&buf->rb_lock);
956 r_xprt->rx_stats.mrs_allocated += count;
957 trace_xprtrdma_createmrs(r_xprt, count);
961 rpcrdma_mr_refresh_worker(struct work_struct *work)
963 struct rpcrdma_buffer *buf = container_of(work, struct rpcrdma_buffer,
965 struct rpcrdma_xprt *r_xprt = container_of(buf, struct rpcrdma_xprt,
968 rpcrdma_mrs_create(r_xprt);
969 xprt_write_space(&r_xprt->rx_xprt);
973 * rpcrdma_mrs_refresh - Wake the MR refresh worker
974 * @r_xprt: controlling transport instance
977 void rpcrdma_mrs_refresh(struct rpcrdma_xprt *r_xprt)
979 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
980 struct rpcrdma_ep *ep = &r_xprt->rx_ep;
982 /* If there is no underlying device, it's no use to
983 * wake the refresh worker.
985 if (ep->rep_connected != -ENODEV) {
986 /* The work is scheduled on a WQ_MEM_RECLAIM
987 * workqueue in order to prevent MR allocation
988 * from recursing into NFS during direct reclaim.
990 queue_work(xprtiod_workqueue, &buf->rb_refresh_worker);
995 * rpcrdma_req_create - Allocate an rpcrdma_req object
996 * @r_xprt: controlling r_xprt
997 * @size: initial size, in bytes, of send and receive buffers
998 * @flags: GFP flags passed to memory allocators
1000 * Returns an allocated and fully initialized rpcrdma_req or NULL.
1002 struct rpcrdma_req *rpcrdma_req_create(struct rpcrdma_xprt *r_xprt, size_t size,
1005 struct rpcrdma_buffer *buffer = &r_xprt->rx_buf;
1006 struct rpcrdma_regbuf *rb;
1007 struct rpcrdma_req *req;
1010 req = kzalloc(sizeof(*req), flags);
1014 /* Compute maximum header buffer size in bytes */
1015 maxhdrsize = rpcrdma_fixed_maxsz + 3 +
1016 r_xprt->rx_ia.ri_max_segs * rpcrdma_readchunk_maxsz;
1017 maxhdrsize *= sizeof(__be32);
1018 rb = rpcrdma_regbuf_alloc(__roundup_pow_of_two(maxhdrsize),
1019 DMA_TO_DEVICE, flags);
1022 req->rl_rdmabuf = rb;
1023 xdr_buf_init(&req->rl_hdrbuf, rdmab_data(rb), rdmab_length(rb));
1025 req->rl_sendbuf = rpcrdma_regbuf_alloc(size, DMA_TO_DEVICE, flags);
1026 if (!req->rl_sendbuf)
1029 req->rl_recvbuf = rpcrdma_regbuf_alloc(size, DMA_NONE, flags);
1030 if (!req->rl_recvbuf)
1033 INIT_LIST_HEAD(&req->rl_free_mrs);
1034 INIT_LIST_HEAD(&req->rl_registered);
1035 spin_lock(&buffer->rb_lock);
1036 list_add(&req->rl_all, &buffer->rb_allreqs);
1037 spin_unlock(&buffer->rb_lock);
1041 kfree(req->rl_sendbuf);
1043 kfree(req->rl_rdmabuf);
1051 * rpcrdma_reqs_reset - Reset all reqs owned by a transport
1052 * @r_xprt: controlling transport instance
1054 * ASSUMPTION: the rb_allreqs list is stable for the duration,
1055 * and thus can be walked without holding rb_lock. Eg. the
1056 * caller is holding the transport send lock to exclude
1057 * device removal or disconnection.
1059 static void rpcrdma_reqs_reset(struct rpcrdma_xprt *r_xprt)
1061 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1062 struct rpcrdma_req *req;
1064 list_for_each_entry(req, &buf->rb_allreqs, rl_all) {
1065 /* Credits are valid only for one connection */
1066 req->rl_slot.rq_cong = 0;
1070 static struct rpcrdma_rep *rpcrdma_rep_create(struct rpcrdma_xprt *r_xprt,
1073 struct rpcrdma_rep *rep;
1075 rep = kzalloc(sizeof(*rep), GFP_KERNEL);
1079 rep->rr_rdmabuf = rpcrdma_regbuf_alloc(r_xprt->rx_ep.rep_inline_recv,
1080 DMA_FROM_DEVICE, GFP_KERNEL);
1081 if (!rep->rr_rdmabuf)
1084 xdr_buf_init(&rep->rr_hdrbuf, rdmab_data(rep->rr_rdmabuf),
1085 rdmab_length(rep->rr_rdmabuf));
1086 rep->rr_cqe.done = rpcrdma_wc_receive;
1087 rep->rr_rxprt = r_xprt;
1088 rep->rr_recv_wr.next = NULL;
1089 rep->rr_recv_wr.wr_cqe = &rep->rr_cqe;
1090 rep->rr_recv_wr.sg_list = &rep->rr_rdmabuf->rg_iov;
1091 rep->rr_recv_wr.num_sge = 1;
1092 rep->rr_temp = temp;
1101 static void rpcrdma_rep_destroy(struct rpcrdma_rep *rep)
1103 rpcrdma_regbuf_free(rep->rr_rdmabuf);
1107 static struct rpcrdma_rep *rpcrdma_rep_get_locked(struct rpcrdma_buffer *buf)
1109 struct llist_node *node;
1111 /* Calls to llist_del_first are required to be serialized */
1112 node = llist_del_first(&buf->rb_free_reps);
1115 return llist_entry(node, struct rpcrdma_rep, rr_node);
1118 static void rpcrdma_rep_put(struct rpcrdma_buffer *buf,
1119 struct rpcrdma_rep *rep)
1122 llist_add(&rep->rr_node, &buf->rb_free_reps);
1124 rpcrdma_rep_destroy(rep);
1127 static void rpcrdma_reps_destroy(struct rpcrdma_buffer *buf)
1129 struct rpcrdma_rep *rep;
1131 while ((rep = rpcrdma_rep_get_locked(buf)) != NULL)
1132 rpcrdma_rep_destroy(rep);
1136 * rpcrdma_buffer_create - Create initial set of req/rep objects
1137 * @r_xprt: transport instance to (re)initialize
1139 * Returns zero on success, otherwise a negative errno.
1141 int rpcrdma_buffer_create(struct rpcrdma_xprt *r_xprt)
1143 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1146 buf->rb_max_requests = r_xprt->rx_ep.rep_max_requests;
1147 buf->rb_bc_srv_max_requests = 0;
1148 spin_lock_init(&buf->rb_lock);
1149 INIT_LIST_HEAD(&buf->rb_mrs);
1150 INIT_LIST_HEAD(&buf->rb_all_mrs);
1151 INIT_WORK(&buf->rb_refresh_worker, rpcrdma_mr_refresh_worker);
1153 INIT_LIST_HEAD(&buf->rb_send_bufs);
1154 INIT_LIST_HEAD(&buf->rb_allreqs);
1157 for (i = 0; i < buf->rb_max_requests; i++) {
1158 struct rpcrdma_req *req;
1160 req = rpcrdma_req_create(r_xprt, RPCRDMA_V1_DEF_INLINE_SIZE * 2,
1164 list_add(&req->rl_list, &buf->rb_send_bufs);
1167 init_llist_head(&buf->rb_free_reps);
1169 rc = rpcrdma_sendctxs_create(r_xprt);
1175 rpcrdma_buffer_destroy(buf);
1180 * rpcrdma_req_destroy - Destroy an rpcrdma_req object
1181 * @req: unused object to be destroyed
1183 * Relies on caller holding the transport send lock to protect
1184 * removing req->rl_all from buf->rb_all_reqs safely.
1186 void rpcrdma_req_destroy(struct rpcrdma_req *req)
1188 struct rpcrdma_mr *mr;
1190 list_del(&req->rl_all);
1192 while ((mr = rpcrdma_mr_pop(&req->rl_free_mrs))) {
1193 struct rpcrdma_buffer *buf = &mr->mr_xprt->rx_buf;
1195 spin_lock(&buf->rb_lock);
1196 list_del(&mr->mr_all);
1197 spin_unlock(&buf->rb_lock);
1199 frwr_release_mr(mr);
1202 rpcrdma_regbuf_free(req->rl_recvbuf);
1203 rpcrdma_regbuf_free(req->rl_sendbuf);
1204 rpcrdma_regbuf_free(req->rl_rdmabuf);
1209 * rpcrdma_mrs_destroy - Release all of a transport's MRs
1210 * @r_xprt: controlling transport instance
1212 * Relies on caller holding the transport send lock to protect
1213 * removing mr->mr_list from req->rl_free_mrs safely.
1215 static void rpcrdma_mrs_destroy(struct rpcrdma_xprt *r_xprt)
1217 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1218 struct rpcrdma_mr *mr;
1220 cancel_work_sync(&buf->rb_refresh_worker);
1222 spin_lock(&buf->rb_lock);
1223 while ((mr = list_first_entry_or_null(&buf->rb_all_mrs,
1226 list_del(&mr->mr_list);
1227 list_del(&mr->mr_all);
1228 spin_unlock(&buf->rb_lock);
1230 frwr_release_mr(mr);
1232 spin_lock(&buf->rb_lock);
1234 spin_unlock(&buf->rb_lock);
1238 * rpcrdma_buffer_destroy - Release all hw resources
1239 * @buf: root control block for resources
1241 * ORDERING: relies on a prior rpcrdma_xprt_drain :
1242 * - No more Send or Receive completions can occur
1243 * - All MRs, reps, and reqs are returned to their free lists
1246 rpcrdma_buffer_destroy(struct rpcrdma_buffer *buf)
1248 rpcrdma_sendctxs_destroy(buf);
1249 rpcrdma_reps_destroy(buf);
1251 while (!list_empty(&buf->rb_send_bufs)) {
1252 struct rpcrdma_req *req;
1254 req = list_first_entry(&buf->rb_send_bufs,
1255 struct rpcrdma_req, rl_list);
1256 list_del(&req->rl_list);
1257 rpcrdma_req_destroy(req);
1262 * rpcrdma_mr_get - Allocate an rpcrdma_mr object
1263 * @r_xprt: controlling transport
1265 * Returns an initialized rpcrdma_mr or NULL if no free
1266 * rpcrdma_mr objects are available.
1269 rpcrdma_mr_get(struct rpcrdma_xprt *r_xprt)
1271 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1272 struct rpcrdma_mr *mr;
1274 spin_lock(&buf->rb_lock);
1275 mr = rpcrdma_mr_pop(&buf->rb_mrs);
1276 spin_unlock(&buf->rb_lock);
1281 * rpcrdma_mr_put - DMA unmap an MR and release it
1282 * @mr: MR to release
1285 void rpcrdma_mr_put(struct rpcrdma_mr *mr)
1287 struct rpcrdma_xprt *r_xprt = mr->mr_xprt;
1289 if (mr->mr_dir != DMA_NONE) {
1290 trace_xprtrdma_mr_unmap(mr);
1291 ib_dma_unmap_sg(r_xprt->rx_ia.ri_id->device,
1292 mr->mr_sg, mr->mr_nents, mr->mr_dir);
1293 mr->mr_dir = DMA_NONE;
1296 rpcrdma_mr_push(mr, &mr->mr_req->rl_free_mrs);
1300 * rpcrdma_buffer_get - Get a request buffer
1301 * @buffers: Buffer pool from which to obtain a buffer
1303 * Returns a fresh rpcrdma_req, or NULL if none are available.
1305 struct rpcrdma_req *
1306 rpcrdma_buffer_get(struct rpcrdma_buffer *buffers)
1308 struct rpcrdma_req *req;
1310 spin_lock(&buffers->rb_lock);
1311 req = list_first_entry_or_null(&buffers->rb_send_bufs,
1312 struct rpcrdma_req, rl_list);
1314 list_del_init(&req->rl_list);
1315 spin_unlock(&buffers->rb_lock);
1320 * rpcrdma_buffer_put - Put request/reply buffers back into pool
1321 * @buffers: buffer pool
1322 * @req: object to return
1325 void rpcrdma_buffer_put(struct rpcrdma_buffer *buffers, struct rpcrdma_req *req)
1328 rpcrdma_rep_put(buffers, req->rl_reply);
1329 req->rl_reply = NULL;
1331 spin_lock(&buffers->rb_lock);
1332 list_add(&req->rl_list, &buffers->rb_send_bufs);
1333 spin_unlock(&buffers->rb_lock);
1337 * rpcrdma_recv_buffer_put - Release rpcrdma_rep back to free list
1338 * @rep: rep to release
1340 * Used after error conditions.
1342 void rpcrdma_recv_buffer_put(struct rpcrdma_rep *rep)
1344 rpcrdma_rep_put(&rep->rr_rxprt->rx_buf, rep);
1347 /* Returns a pointer to a rpcrdma_regbuf object, or NULL.
1349 * xprtrdma uses a regbuf for posting an outgoing RDMA SEND, or for
1350 * receiving the payload of RDMA RECV operations. During Long Calls
1351 * or Replies they may be registered externally via frwr_map.
1353 static struct rpcrdma_regbuf *
1354 rpcrdma_regbuf_alloc(size_t size, enum dma_data_direction direction,
1357 struct rpcrdma_regbuf *rb;
1359 rb = kmalloc(sizeof(*rb), flags);
1362 rb->rg_data = kmalloc(size, flags);
1368 rb->rg_device = NULL;
1369 rb->rg_direction = direction;
1370 rb->rg_iov.length = size;
1375 * rpcrdma_regbuf_realloc - re-allocate a SEND/RECV buffer
1376 * @rb: regbuf to reallocate
1377 * @size: size of buffer to be allocated, in bytes
1380 * Returns true if reallocation was successful. If false is
1381 * returned, @rb is left untouched.
1383 bool rpcrdma_regbuf_realloc(struct rpcrdma_regbuf *rb, size_t size, gfp_t flags)
1387 buf = kmalloc(size, flags);
1391 rpcrdma_regbuf_dma_unmap(rb);
1395 rb->rg_iov.length = size;
1400 * __rpcrdma_regbuf_dma_map - DMA-map a regbuf
1401 * @r_xprt: controlling transport instance
1402 * @rb: regbuf to be mapped
1404 * Returns true if the buffer is now DMA mapped to @r_xprt's device
1406 bool __rpcrdma_regbuf_dma_map(struct rpcrdma_xprt *r_xprt,
1407 struct rpcrdma_regbuf *rb)
1409 struct ib_device *device = r_xprt->rx_ia.ri_id->device;
1411 if (rb->rg_direction == DMA_NONE)
1414 rb->rg_iov.addr = ib_dma_map_single(device, rdmab_data(rb),
1415 rdmab_length(rb), rb->rg_direction);
1416 if (ib_dma_mapping_error(device, rdmab_addr(rb))) {
1417 trace_xprtrdma_dma_maperr(rdmab_addr(rb));
1421 rb->rg_device = device;
1422 rb->rg_iov.lkey = r_xprt->rx_ia.ri_pd->local_dma_lkey;
1426 static void rpcrdma_regbuf_dma_unmap(struct rpcrdma_regbuf *rb)
1431 if (!rpcrdma_regbuf_is_mapped(rb))
1434 ib_dma_unmap_single(rb->rg_device, rdmab_addr(rb), rdmab_length(rb),
1436 rb->rg_device = NULL;
1439 static void rpcrdma_regbuf_free(struct rpcrdma_regbuf *rb)
1441 rpcrdma_regbuf_dma_unmap(rb);
1448 * rpcrdma_ep_post - Post WRs to a transport's Send Queue
1449 * @ia: transport's device information
1450 * @ep: transport's RDMA endpoint information
1451 * @req: rpcrdma_req containing the Send WR to post
1453 * Returns 0 if the post was successful, otherwise -ENOTCONN
1457 rpcrdma_ep_post(struct rpcrdma_ia *ia,
1458 struct rpcrdma_ep *ep,
1459 struct rpcrdma_req *req)
1461 struct ib_send_wr *send_wr = &req->rl_wr;
1464 if (!ep->rep_send_count || kref_read(&req->rl_kref) > 1) {
1465 send_wr->send_flags |= IB_SEND_SIGNALED;
1466 ep->rep_send_count = ep->rep_send_batch;
1468 send_wr->send_flags &= ~IB_SEND_SIGNALED;
1469 --ep->rep_send_count;
1472 rc = frwr_send(ia, req);
1473 trace_xprtrdma_post_send(req, rc);
1480 * rpcrdma_post_recvs - Refill the Receive Queue
1481 * @r_xprt: controlling transport instance
1482 * @temp: mark Receive buffers to be deleted after use
1485 void rpcrdma_post_recvs(struct rpcrdma_xprt *r_xprt, bool temp)
1487 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1488 struct rpcrdma_ep *ep = &r_xprt->rx_ep;
1489 struct ib_recv_wr *i, *wr, *bad_wr;
1490 struct rpcrdma_rep *rep;
1491 int needed, count, rc;
1496 needed = buf->rb_credits + (buf->rb_bc_srv_max_requests << 1);
1497 if (likely(ep->rep_receive_count > needed))
1499 needed -= ep->rep_receive_count;
1501 needed += RPCRDMA_MAX_RECV_BATCH;
1503 /* fast path: all needed reps can be found on the free list */
1506 rep = rpcrdma_rep_get_locked(buf);
1508 rep = rpcrdma_rep_create(r_xprt, temp);
1512 rep->rr_recv_wr.next = wr;
1513 wr = &rep->rr_recv_wr;
1519 for (i = wr; i; i = i->next) {
1520 rep = container_of(i, struct rpcrdma_rep, rr_recv_wr);
1522 if (!rpcrdma_regbuf_dma_map(r_xprt, rep->rr_rdmabuf))
1525 trace_xprtrdma_post_recv(rep);
1529 rc = ib_post_recv(r_xprt->rx_ia.ri_id->qp, wr,
1530 (const struct ib_recv_wr **)&bad_wr);
1532 trace_xprtrdma_post_recvs(r_xprt, count, rc);
1534 for (wr = bad_wr; wr;) {
1535 struct rpcrdma_rep *rep;
1537 rep = container_of(wr, struct rpcrdma_rep, rr_recv_wr);
1539 rpcrdma_recv_buffer_put(rep);
1543 ep->rep_receive_count += count;
1548 rep = container_of(i, struct rpcrdma_rep, rr_recv_wr);
1550 rpcrdma_recv_buffer_put(rep);