2 * Copyright (c) 2014-2017 Oracle. All rights reserved.
3 * Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
5 * This software is available to you under a choice of one of two
6 * licenses. You may choose to be licensed under the terms of the GNU
7 * General Public License (GPL) Version 2, available from the file
8 * COPYING in the main directory of this source tree, or the BSD-type
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
15 * Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
18 * Redistributions in binary form must reproduce the above
19 * copyright notice, this list of conditions and the following
20 * disclaimer in the documentation and/or other materials provided
21 * with the distribution.
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24 * its contributors may be used to endorse or promote products
25 * derived from this software without specific prior written
28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
44 * Encapsulates the major functions managing:
51 #include <linux/interrupt.h>
52 #include <linux/slab.h>
53 #include <linux/sunrpc/addr.h>
54 #include <linux/sunrpc/svc_rdma.h>
56 #include <asm-generic/barrier.h>
57 #include <asm/bitops.h>
59 #include <rdma/ib_cm.h>
61 #include "xprt_rdma.h"
67 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
68 # define RPCDBG_FACILITY RPCDBG_TRANS
74 static void rpcrdma_create_mrs(struct rpcrdma_xprt *r_xprt);
75 static void rpcrdma_destroy_mrs(struct rpcrdma_buffer *buf);
76 static void rpcrdma_dma_unmap_regbuf(struct rpcrdma_regbuf *rb);
78 struct workqueue_struct *rpcrdma_receive_wq __read_mostly;
81 rpcrdma_alloc_wq(void)
83 struct workqueue_struct *recv_wq;
85 recv_wq = alloc_workqueue("xprtrdma_receive",
86 WQ_MEM_RECLAIM | WQ_HIGHPRI,
91 rpcrdma_receive_wq = recv_wq;
96 rpcrdma_destroy_wq(void)
98 struct workqueue_struct *wq;
100 if (rpcrdma_receive_wq) {
101 wq = rpcrdma_receive_wq;
102 rpcrdma_receive_wq = NULL;
103 destroy_workqueue(wq);
108 rpcrdma_qp_async_error_upcall(struct ib_event *event, void *context)
110 struct rpcrdma_ep *ep = context;
112 pr_err("rpcrdma: %s on device %s ep %p\n",
113 ib_event_msg(event->event), event->device->name, context);
115 if (ep->rep_connected == 1) {
116 ep->rep_connected = -EIO;
117 rpcrdma_conn_func(ep);
118 wake_up_all(&ep->rep_connect_wait);
123 * rpcrdma_wc_send - Invoked by RDMA provider for each polled Send WC
124 * @cq: completion queue (ignored)
129 rpcrdma_wc_send(struct ib_cq *cq, struct ib_wc *wc)
131 struct ib_cqe *cqe = wc->wr_cqe;
132 struct rpcrdma_sendctx *sc =
133 container_of(cqe, struct rpcrdma_sendctx, sc_cqe);
135 /* WARNING: Only wr_cqe and status are reliable at this point */
136 if (wc->status != IB_WC_SUCCESS && wc->status != IB_WC_WR_FLUSH_ERR)
137 pr_err("rpcrdma: Send: %s (%u/0x%x)\n",
138 ib_wc_status_msg(wc->status),
139 wc->status, wc->vendor_err);
141 rpcrdma_sendctx_put_locked(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,
157 /* WARNING: Only wr_id and status are reliable at this point */
158 if (wc->status != IB_WC_SUCCESS)
161 /* status == SUCCESS means all fields in wc are trustworthy */
162 dprintk("RPC: %s: rep %p opcode 'recv', length %u: success\n",
163 __func__, rep, wc->byte_len);
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);
174 rpcrdma_reply_handler(rep);
178 if (wc->status != IB_WC_WR_FLUSH_ERR)
179 pr_err("rpcrdma: Recv: %s (%u/0x%x)\n",
180 ib_wc_status_msg(wc->status),
181 wc->status, wc->vendor_err);
182 rpcrdma_set_xdrlen(&rep->rr_hdrbuf, 0);
187 rpcrdma_update_connect_private(struct rpcrdma_xprt *r_xprt,
188 struct rdma_conn_param *param)
190 struct rpcrdma_create_data_internal *cdata = &r_xprt->rx_data;
191 const struct rpcrdma_connect_private *pmsg = param->private_data;
192 unsigned int rsize, wsize;
194 /* Default settings for RPC-over-RDMA Version One */
195 r_xprt->rx_ia.ri_reminv_expected = false;
196 r_xprt->rx_ia.ri_implicit_roundup = xprt_rdma_pad_optimize;
197 rsize = RPCRDMA_V1_DEF_INLINE_SIZE;
198 wsize = RPCRDMA_V1_DEF_INLINE_SIZE;
201 pmsg->cp_magic == rpcrdma_cmp_magic &&
202 pmsg->cp_version == RPCRDMA_CMP_VERSION) {
203 r_xprt->rx_ia.ri_reminv_expected = true;
204 r_xprt->rx_ia.ri_implicit_roundup = true;
205 rsize = rpcrdma_decode_buffer_size(pmsg->cp_send_size);
206 wsize = rpcrdma_decode_buffer_size(pmsg->cp_recv_size);
209 if (rsize < cdata->inline_rsize)
210 cdata->inline_rsize = rsize;
211 if (wsize < cdata->inline_wsize)
212 cdata->inline_wsize = wsize;
213 dprintk("RPC: %s: max send %u, max recv %u\n",
214 __func__, cdata->inline_wsize, cdata->inline_rsize);
215 rpcrdma_set_max_header_sizes(r_xprt);
219 rpcrdma_conn_upcall(struct rdma_cm_id *id, struct rdma_cm_event *event)
221 struct rpcrdma_xprt *xprt = id->context;
222 struct rpcrdma_ia *ia = &xprt->rx_ia;
223 struct rpcrdma_ep *ep = &xprt->rx_ep;
224 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
225 struct sockaddr *sap = (struct sockaddr *)&ep->rep_remote_addr;
229 switch (event->event) {
230 case RDMA_CM_EVENT_ADDR_RESOLVED:
231 case RDMA_CM_EVENT_ROUTE_RESOLVED:
233 complete(&ia->ri_done);
235 case RDMA_CM_EVENT_ADDR_ERROR:
236 ia->ri_async_rc = -EHOSTUNREACH;
237 dprintk("RPC: %s: CM address resolution error, ep 0x%p\n",
239 complete(&ia->ri_done);
241 case RDMA_CM_EVENT_ROUTE_ERROR:
242 ia->ri_async_rc = -ENETUNREACH;
243 dprintk("RPC: %s: CM route resolution error, ep 0x%p\n",
245 complete(&ia->ri_done);
247 case RDMA_CM_EVENT_DEVICE_REMOVAL:
248 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
249 pr_info("rpcrdma: removing device %s for %pIS:%u\n",
251 sap, rpc_get_port(sap));
253 set_bit(RPCRDMA_IAF_REMOVING, &ia->ri_flags);
254 ep->rep_connected = -ENODEV;
255 xprt_force_disconnect(&xprt->rx_xprt);
256 wait_for_completion(&ia->ri_remove_done);
260 ia->ri_device = NULL;
261 /* Return 1 to ensure the core destroys the id. */
263 case RDMA_CM_EVENT_ESTABLISHED:
265 rpcrdma_update_connect_private(xprt, &event->param.conn);
267 case RDMA_CM_EVENT_CONNECT_ERROR:
268 connstate = -ENOTCONN;
270 case RDMA_CM_EVENT_UNREACHABLE:
271 connstate = -ENETDOWN;
273 case RDMA_CM_EVENT_REJECTED:
274 dprintk("rpcrdma: connection to %pIS:%u rejected: %s\n",
275 sap, rpc_get_port(sap),
276 rdma_reject_msg(id, event->status));
277 connstate = -ECONNREFUSED;
278 if (event->status == IB_CM_REJ_STALE_CONN)
281 case RDMA_CM_EVENT_DISCONNECTED:
282 connstate = -ECONNABORTED;
284 xprt->rx_buf.rb_credits = 1;
285 ep->rep_connected = connstate;
286 rpcrdma_conn_func(ep);
287 wake_up_all(&ep->rep_connect_wait);
290 dprintk("RPC: %s: %pIS:%u on %s/%s (ep 0x%p): %s\n",
291 __func__, sap, rpc_get_port(sap),
292 ia->ri_device->name, ia->ri_ops->ro_displayname,
293 ep, rdma_event_msg(event->event));
300 static struct rdma_cm_id *
301 rpcrdma_create_id(struct rpcrdma_xprt *xprt,
302 struct rpcrdma_ia *ia, struct sockaddr *addr)
304 unsigned long wtimeout = msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT) + 1;
305 struct rdma_cm_id *id;
308 init_completion(&ia->ri_done);
309 init_completion(&ia->ri_remove_done);
311 id = rdma_create_id(&init_net, rpcrdma_conn_upcall, xprt, RDMA_PS_TCP,
315 dprintk("RPC: %s: rdma_create_id() failed %i\n",
320 ia->ri_async_rc = -ETIMEDOUT;
321 rc = rdma_resolve_addr(id, NULL, addr, RDMA_RESOLVE_TIMEOUT);
323 dprintk("RPC: %s: rdma_resolve_addr() failed %i\n",
327 rc = wait_for_completion_interruptible_timeout(&ia->ri_done, wtimeout);
329 dprintk("RPC: %s: wait() exited: %i\n",
334 rc = ia->ri_async_rc;
338 ia->ri_async_rc = -ETIMEDOUT;
339 rc = rdma_resolve_route(id, RDMA_RESOLVE_TIMEOUT);
341 dprintk("RPC: %s: rdma_resolve_route() failed %i\n",
345 rc = wait_for_completion_interruptible_timeout(&ia->ri_done, wtimeout);
347 dprintk("RPC: %s: wait() exited: %i\n",
351 rc = ia->ri_async_rc;
363 * Exported functions.
367 * rpcrdma_ia_open - Open and initialize an Interface Adapter.
368 * @xprt: controlling transport
369 * @addr: IP address of remote peer
371 * Returns 0 on success, negative errno if an appropriate
372 * Interface Adapter could not be found and opened.
375 rpcrdma_ia_open(struct rpcrdma_xprt *xprt, struct sockaddr *addr)
377 struct rpcrdma_ia *ia = &xprt->rx_ia;
380 ia->ri_id = rpcrdma_create_id(xprt, ia, addr);
381 if (IS_ERR(ia->ri_id)) {
382 rc = PTR_ERR(ia->ri_id);
385 ia->ri_device = ia->ri_id->device;
387 ia->ri_pd = ib_alloc_pd(ia->ri_device, 0);
388 if (IS_ERR(ia->ri_pd)) {
389 rc = PTR_ERR(ia->ri_pd);
390 pr_err("rpcrdma: ib_alloc_pd() returned %d\n", rc);
394 switch (xprt_rdma_memreg_strategy) {
396 if (frwr_is_supported(ia)) {
397 ia->ri_ops = &rpcrdma_frwr_memreg_ops;
401 case RPCRDMA_MTHCAFMR:
402 if (fmr_is_supported(ia)) {
403 ia->ri_ops = &rpcrdma_fmr_memreg_ops;
408 pr_err("rpcrdma: Device %s does not support memreg mode %d\n",
409 ia->ri_device->name, xprt_rdma_memreg_strategy);
417 rpcrdma_ia_close(ia);
422 * rpcrdma_ia_remove - Handle device driver unload
423 * @ia: interface adapter being removed
425 * Divest transport H/W resources associated with this adapter,
426 * but allow it to be restored later.
429 rpcrdma_ia_remove(struct rpcrdma_ia *ia)
431 struct rpcrdma_xprt *r_xprt = container_of(ia, struct rpcrdma_xprt,
433 struct rpcrdma_ep *ep = &r_xprt->rx_ep;
434 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
435 struct rpcrdma_req *req;
436 struct rpcrdma_rep *rep;
438 cancel_delayed_work_sync(&buf->rb_refresh_worker);
440 /* This is similar to rpcrdma_ep_destroy, but:
441 * - Don't cancel the connect worker.
442 * - Don't call rpcrdma_ep_disconnect, which waits
443 * for another conn upcall, which will deadlock.
444 * - rdma_disconnect is unneeded, the underlying
445 * connection is already gone.
448 ib_drain_qp(ia->ri_id->qp);
449 rdma_destroy_qp(ia->ri_id);
450 ia->ri_id->qp = NULL;
452 ib_free_cq(ep->rep_attr.recv_cq);
453 ib_free_cq(ep->rep_attr.send_cq);
455 /* The ULP is responsible for ensuring all DMA
456 * mappings and MRs are gone.
458 list_for_each_entry(rep, &buf->rb_recv_bufs, rr_list)
459 rpcrdma_dma_unmap_regbuf(rep->rr_rdmabuf);
460 list_for_each_entry(req, &buf->rb_allreqs, rl_all) {
461 rpcrdma_dma_unmap_regbuf(req->rl_rdmabuf);
462 rpcrdma_dma_unmap_regbuf(req->rl_sendbuf);
463 rpcrdma_dma_unmap_regbuf(req->rl_recvbuf);
465 rpcrdma_destroy_mrs(buf);
467 /* Allow waiters to continue */
468 complete(&ia->ri_remove_done);
472 * rpcrdma_ia_close - Clean up/close an IA.
473 * @ia: interface adapter to close
477 rpcrdma_ia_close(struct rpcrdma_ia *ia)
479 dprintk("RPC: %s: entering\n", __func__);
480 if (ia->ri_id != NULL && !IS_ERR(ia->ri_id)) {
482 rdma_destroy_qp(ia->ri_id);
483 rdma_destroy_id(ia->ri_id);
486 ia->ri_device = NULL;
488 /* If the pd is still busy, xprtrdma missed freeing a resource */
489 if (ia->ri_pd && !IS_ERR(ia->ri_pd))
490 ib_dealloc_pd(ia->ri_pd);
495 * Create unconnected endpoint.
498 rpcrdma_ep_create(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia,
499 struct rpcrdma_create_data_internal *cdata)
501 struct rpcrdma_connect_private *pmsg = &ep->rep_cm_private;
502 unsigned int max_qp_wr, max_sge;
503 struct ib_cq *sendcq, *recvcq;
506 max_sge = min_t(unsigned int, ia->ri_device->attrs.max_sge,
507 RPCRDMA_MAX_SEND_SGES);
508 if (max_sge < RPCRDMA_MIN_SEND_SGES) {
509 pr_warn("rpcrdma: HCA provides only %d send SGEs\n", max_sge);
512 ia->ri_max_send_sges = max_sge - RPCRDMA_MIN_SEND_SGES;
514 if (ia->ri_device->attrs.max_qp_wr <= RPCRDMA_BACKWARD_WRS) {
515 dprintk("RPC: %s: insufficient wqe's available\n",
519 max_qp_wr = ia->ri_device->attrs.max_qp_wr - RPCRDMA_BACKWARD_WRS - 1;
521 /* check provider's send/recv wr limits */
522 if (cdata->max_requests > max_qp_wr)
523 cdata->max_requests = max_qp_wr;
525 ep->rep_attr.event_handler = rpcrdma_qp_async_error_upcall;
526 ep->rep_attr.qp_context = ep;
527 ep->rep_attr.srq = NULL;
528 ep->rep_attr.cap.max_send_wr = cdata->max_requests;
529 ep->rep_attr.cap.max_send_wr += RPCRDMA_BACKWARD_WRS;
530 ep->rep_attr.cap.max_send_wr += 1; /* drain cqe */
531 rc = ia->ri_ops->ro_open(ia, ep, cdata);
534 ep->rep_attr.cap.max_recv_wr = cdata->max_requests;
535 ep->rep_attr.cap.max_recv_wr += RPCRDMA_BACKWARD_WRS;
536 ep->rep_attr.cap.max_recv_wr += 1; /* drain cqe */
537 ep->rep_attr.cap.max_send_sge = max_sge;
538 ep->rep_attr.cap.max_recv_sge = 1;
539 ep->rep_attr.cap.max_inline_data = 0;
540 ep->rep_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
541 ep->rep_attr.qp_type = IB_QPT_RC;
542 ep->rep_attr.port_num = ~0;
544 dprintk("RPC: %s: requested max: dtos: send %d recv %d; "
545 "iovs: send %d recv %d\n",
547 ep->rep_attr.cap.max_send_wr,
548 ep->rep_attr.cap.max_recv_wr,
549 ep->rep_attr.cap.max_send_sge,
550 ep->rep_attr.cap.max_recv_sge);
552 /* set trigger for requesting send completion */
553 ep->rep_send_batch = min_t(unsigned int, RPCRDMA_MAX_SEND_BATCH,
554 cdata->max_requests >> 2);
555 ep->rep_send_count = ep->rep_send_batch;
556 init_waitqueue_head(&ep->rep_connect_wait);
557 INIT_DELAYED_WORK(&ep->rep_connect_worker, rpcrdma_connect_worker);
559 sendcq = ib_alloc_cq(ia->ri_device, NULL,
560 ep->rep_attr.cap.max_send_wr + 1,
561 1, IB_POLL_WORKQUEUE);
562 if (IS_ERR(sendcq)) {
563 rc = PTR_ERR(sendcq);
564 dprintk("RPC: %s: failed to create send CQ: %i\n",
569 recvcq = ib_alloc_cq(ia->ri_device, NULL,
570 ep->rep_attr.cap.max_recv_wr + 1,
571 0, IB_POLL_WORKQUEUE);
572 if (IS_ERR(recvcq)) {
573 rc = PTR_ERR(recvcq);
574 dprintk("RPC: %s: failed to create recv CQ: %i\n",
579 ep->rep_attr.send_cq = sendcq;
580 ep->rep_attr.recv_cq = recvcq;
582 /* Initialize cma parameters */
583 memset(&ep->rep_remote_cma, 0, sizeof(ep->rep_remote_cma));
585 /* Prepare RDMA-CM private message */
586 pmsg->cp_magic = rpcrdma_cmp_magic;
587 pmsg->cp_version = RPCRDMA_CMP_VERSION;
588 pmsg->cp_flags |= ia->ri_ops->ro_send_w_inv_ok;
589 pmsg->cp_send_size = rpcrdma_encode_buffer_size(cdata->inline_wsize);
590 pmsg->cp_recv_size = rpcrdma_encode_buffer_size(cdata->inline_rsize);
591 ep->rep_remote_cma.private_data = pmsg;
592 ep->rep_remote_cma.private_data_len = sizeof(*pmsg);
594 /* Client offers RDMA Read but does not initiate */
595 ep->rep_remote_cma.initiator_depth = 0;
596 if (ia->ri_device->attrs.max_qp_rd_atom > 32) /* arbitrary but <= 255 */
597 ep->rep_remote_cma.responder_resources = 32;
599 ep->rep_remote_cma.responder_resources =
600 ia->ri_device->attrs.max_qp_rd_atom;
602 /* Limit transport retries so client can detect server
603 * GID changes quickly. RPC layer handles re-establishing
604 * transport connection and retransmission.
606 ep->rep_remote_cma.retry_count = 6;
608 /* RPC-over-RDMA handles its own flow control. In addition,
609 * make all RNR NAKs visible so we know that RPC-over-RDMA
610 * flow control is working correctly (no NAKs should be seen).
612 ep->rep_remote_cma.flow_control = 0;
613 ep->rep_remote_cma.rnr_retry_count = 0;
626 * Disconnect and destroy endpoint. After this, the only
627 * valid operations on the ep are to free it (if dynamically
628 * allocated) or re-create it.
631 rpcrdma_ep_destroy(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
633 dprintk("RPC: %s: entering, connected is %d\n",
634 __func__, ep->rep_connected);
636 cancel_delayed_work_sync(&ep->rep_connect_worker);
639 rpcrdma_ep_disconnect(ep, ia);
640 rdma_destroy_qp(ia->ri_id);
641 ia->ri_id->qp = NULL;
644 ib_free_cq(ep->rep_attr.recv_cq);
645 ib_free_cq(ep->rep_attr.send_cq);
648 /* Re-establish a connection after a device removal event.
649 * Unlike a normal reconnection, a fresh PD and a new set
650 * of MRs and buffers is needed.
653 rpcrdma_ep_recreate_xprt(struct rpcrdma_xprt *r_xprt,
654 struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
656 struct sockaddr *sap = (struct sockaddr *)&r_xprt->rx_data.addr;
659 pr_info("%s: r_xprt = %p\n", __func__, r_xprt);
662 if (rpcrdma_ia_open(r_xprt, sap))
666 err = rpcrdma_ep_create(ep, ia, &r_xprt->rx_data);
668 pr_err("rpcrdma: rpcrdma_ep_create returned %d\n", err);
673 err = rdma_create_qp(ia->ri_id, ia->ri_pd, &ep->rep_attr);
675 pr_err("rpcrdma: rdma_create_qp returned %d\n", err);
679 rpcrdma_create_mrs(r_xprt);
683 rpcrdma_ep_destroy(ep, ia);
685 rpcrdma_ia_close(ia);
691 rpcrdma_ep_reconnect(struct rpcrdma_xprt *r_xprt, struct rpcrdma_ep *ep,
692 struct rpcrdma_ia *ia)
694 struct sockaddr *sap = (struct sockaddr *)&r_xprt->rx_data.addr;
695 struct rdma_cm_id *id, *old;
698 dprintk("RPC: %s: reconnecting...\n", __func__);
700 rpcrdma_ep_disconnect(ep, ia);
703 id = rpcrdma_create_id(r_xprt, ia, sap);
707 /* As long as the new ID points to the same device as the
708 * old ID, we can reuse the transport's existing PD and all
709 * previously allocated MRs. Also, the same device means
710 * the transport's previous DMA mappings are still valid.
712 * This is a sanity check only. There should be no way these
713 * point to two different devices here.
717 if (ia->ri_device != id->device) {
718 pr_err("rpcrdma: can't reconnect on different device!\n");
722 err = rdma_create_qp(id, ia->ri_pd, &ep->rep_attr);
724 dprintk("RPC: %s: rdma_create_qp returned %d\n",
729 /* Atomically replace the transport's ID and QP. */
733 rdma_destroy_qp(old);
736 rdma_destroy_id(old);
742 * Connect unconnected endpoint.
745 rpcrdma_ep_connect(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
747 struct rpcrdma_xprt *r_xprt = container_of(ia, struct rpcrdma_xprt,
753 switch (ep->rep_connected) {
755 dprintk("RPC: %s: connecting...\n", __func__);
756 rc = rdma_create_qp(ia->ri_id, ia->ri_pd, &ep->rep_attr);
758 dprintk("RPC: %s: rdma_create_qp failed %i\n",
765 rc = rpcrdma_ep_recreate_xprt(r_xprt, ep, ia);
770 rc = rpcrdma_ep_reconnect(r_xprt, ep, ia);
775 ep->rep_connected = 0;
777 rc = rdma_connect(ia->ri_id, &ep->rep_remote_cma);
779 dprintk("RPC: %s: rdma_connect() failed with %i\n",
784 wait_event_interruptible(ep->rep_connect_wait, ep->rep_connected != 0);
785 if (ep->rep_connected <= 0) {
786 if (ep->rep_connected == -EAGAIN)
788 rc = ep->rep_connected;
792 dprintk("RPC: %s: connected\n", __func__);
793 extras = r_xprt->rx_buf.rb_bc_srv_max_requests;
795 rpcrdma_ep_post_extra_recv(r_xprt, extras);
799 ep->rep_connected = rc;
806 * rpcrdma_ep_disconnect
808 * This is separate from destroy to facilitate the ability
809 * to reconnect without recreating the endpoint.
811 * This call is not reentrant, and must not be made in parallel
812 * on the same endpoint.
815 rpcrdma_ep_disconnect(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
819 rc = rdma_disconnect(ia->ri_id);
821 /* returns without wait if not connected */
822 wait_event_interruptible(ep->rep_connect_wait,
823 ep->rep_connected != 1);
824 dprintk("RPC: %s: after wait, %sconnected\n", __func__,
825 (ep->rep_connected == 1) ? "still " : "dis");
827 dprintk("RPC: %s: rdma_disconnect %i\n", __func__, rc);
828 ep->rep_connected = rc;
831 ib_drain_qp(ia->ri_id->qp);
834 /* Fixed-size circular FIFO queue. This implementation is wait-free and
837 * Consumer is the code path that posts Sends. This path dequeues a
838 * sendctx for use by a Send operation. Multiple consumer threads
839 * are serialized by the RPC transport lock, which allows only one
840 * ->send_request call at a time.
842 * Producer is the code path that handles Send completions. This path
843 * enqueues a sendctx that has been completed. Multiple producer
844 * threads are serialized by the ib_poll_cq() function.
847 /* rpcrdma_sendctxs_destroy() assumes caller has already quiesced
848 * queue activity, and ib_drain_qp has flushed all remaining Send
851 static void rpcrdma_sendctxs_destroy(struct rpcrdma_buffer *buf)
855 for (i = 0; i <= buf->rb_sc_last; i++)
856 kfree(buf->rb_sc_ctxs[i]);
857 kfree(buf->rb_sc_ctxs);
860 static struct rpcrdma_sendctx *rpcrdma_sendctx_create(struct rpcrdma_ia *ia)
862 struct rpcrdma_sendctx *sc;
864 sc = kzalloc(sizeof(*sc) +
865 ia->ri_max_send_sges * sizeof(struct ib_sge),
870 sc->sc_wr.wr_cqe = &sc->sc_cqe;
871 sc->sc_wr.sg_list = sc->sc_sges;
872 sc->sc_wr.opcode = IB_WR_SEND;
873 sc->sc_cqe.done = rpcrdma_wc_send;
877 static int rpcrdma_sendctxs_create(struct rpcrdma_xprt *r_xprt)
879 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
880 struct rpcrdma_sendctx *sc;
883 /* Maximum number of concurrent outstanding Send WRs. Capping
884 * the circular queue size stops Send Queue overflow by causing
885 * the ->send_request call to fail temporarily before too many
888 i = buf->rb_max_requests + RPCRDMA_MAX_BC_REQUESTS;
889 dprintk("RPC: %s: allocating %lu send_ctxs\n", __func__, i);
890 buf->rb_sc_ctxs = kcalloc(i, sizeof(sc), GFP_KERNEL);
891 if (!buf->rb_sc_ctxs)
894 buf->rb_sc_last = i - 1;
895 for (i = 0; i <= buf->rb_sc_last; i++) {
896 sc = rpcrdma_sendctx_create(&r_xprt->rx_ia);
900 sc->sc_xprt = r_xprt;
901 buf->rb_sc_ctxs[i] = sc;
907 rpcrdma_sendctxs_destroy(buf);
911 /* The sendctx queue is not guaranteed to have a size that is a
912 * power of two, thus the helpers in circ_buf.h cannot be used.
913 * The other option is to use modulus (%), which can be expensive.
915 static unsigned long rpcrdma_sendctx_next(struct rpcrdma_buffer *buf,
918 return likely(item < buf->rb_sc_last) ? item + 1 : 0;
922 * rpcrdma_sendctx_get_locked - Acquire a send context
923 * @buf: transport buffers from which to acquire an unused context
925 * Returns pointer to a free send completion context; or NULL if
926 * the queue is empty.
928 * Usage: Called to acquire an SGE array before preparing a Send WR.
930 * The caller serializes calls to this function (per rpcrdma_buffer),
931 * and provides an effective memory barrier that flushes the new value
934 struct rpcrdma_sendctx *rpcrdma_sendctx_get_locked(struct rpcrdma_buffer *buf)
936 struct rpcrdma_xprt *r_xprt;
937 struct rpcrdma_sendctx *sc;
938 unsigned long next_head;
940 next_head = rpcrdma_sendctx_next(buf, buf->rb_sc_head);
942 if (next_head == READ_ONCE(buf->rb_sc_tail))
945 /* ORDER: item must be accessed _before_ head is updated */
946 sc = buf->rb_sc_ctxs[next_head];
948 /* Releasing the lock in the caller acts as a memory
949 * barrier that flushes rb_sc_head.
951 buf->rb_sc_head = next_head;
956 /* The queue is "empty" if there have not been enough Send
957 * completions recently. This is a sign the Send Queue is
958 * backing up. Cause the caller to pause and try again.
960 dprintk("RPC: %s: empty sendctx queue\n", __func__);
961 r_xprt = container_of(buf, struct rpcrdma_xprt, rx_buf);
962 r_xprt->rx_stats.empty_sendctx_q++;
967 * rpcrdma_sendctx_put_locked - Release a send context
968 * @sc: send context to release
970 * Usage: Called from Send completion to return a sendctxt
973 * The caller serializes calls to this function (per rpcrdma_buffer).
975 void rpcrdma_sendctx_put_locked(struct rpcrdma_sendctx *sc)
977 struct rpcrdma_buffer *buf = &sc->sc_xprt->rx_buf;
978 unsigned long next_tail;
980 /* Unmap SGEs of previously completed by unsignaled
981 * Sends by walking up the queue until @sc is found.
983 next_tail = buf->rb_sc_tail;
985 next_tail = rpcrdma_sendctx_next(buf, next_tail);
987 /* ORDER: item must be accessed _before_ tail is updated */
988 rpcrdma_unmap_sendctx(buf->rb_sc_ctxs[next_tail]);
990 } while (buf->rb_sc_ctxs[next_tail] != sc);
992 /* Paired with READ_ONCE */
993 smp_store_release(&buf->rb_sc_tail, next_tail);
997 rpcrdma_mr_recovery_worker(struct work_struct *work)
999 struct rpcrdma_buffer *buf = container_of(work, struct rpcrdma_buffer,
1000 rb_recovery_worker.work);
1001 struct rpcrdma_mw *mw;
1003 spin_lock(&buf->rb_recovery_lock);
1004 while (!list_empty(&buf->rb_stale_mrs)) {
1005 mw = rpcrdma_pop_mw(&buf->rb_stale_mrs);
1006 spin_unlock(&buf->rb_recovery_lock);
1008 dprintk("RPC: %s: recovering MR %p\n", __func__, mw);
1009 mw->mw_xprt->rx_ia.ri_ops->ro_recover_mr(mw);
1011 spin_lock(&buf->rb_recovery_lock);
1013 spin_unlock(&buf->rb_recovery_lock);
1017 rpcrdma_defer_mr_recovery(struct rpcrdma_mw *mw)
1019 struct rpcrdma_xprt *r_xprt = mw->mw_xprt;
1020 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1022 spin_lock(&buf->rb_recovery_lock);
1023 rpcrdma_push_mw(mw, &buf->rb_stale_mrs);
1024 spin_unlock(&buf->rb_recovery_lock);
1026 schedule_delayed_work(&buf->rb_recovery_worker, 0);
1030 rpcrdma_create_mrs(struct rpcrdma_xprt *r_xprt)
1032 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1033 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
1038 for (count = 0; count < 32; count++) {
1039 struct rpcrdma_mw *mw;
1042 mw = kzalloc(sizeof(*mw), GFP_KERNEL);
1046 rc = ia->ri_ops->ro_init_mr(ia, mw);
1052 mw->mw_xprt = r_xprt;
1054 list_add(&mw->mw_list, &free);
1055 list_add(&mw->mw_all, &all);
1058 spin_lock(&buf->rb_mwlock);
1059 list_splice(&free, &buf->rb_mws);
1060 list_splice(&all, &buf->rb_all);
1061 r_xprt->rx_stats.mrs_allocated += count;
1062 spin_unlock(&buf->rb_mwlock);
1064 dprintk("RPC: %s: created %u MRs\n", __func__, count);
1068 rpcrdma_mr_refresh_worker(struct work_struct *work)
1070 struct rpcrdma_buffer *buf = container_of(work, struct rpcrdma_buffer,
1071 rb_refresh_worker.work);
1072 struct rpcrdma_xprt *r_xprt = container_of(buf, struct rpcrdma_xprt,
1075 rpcrdma_create_mrs(r_xprt);
1078 struct rpcrdma_req *
1079 rpcrdma_create_req(struct rpcrdma_xprt *r_xprt)
1081 struct rpcrdma_buffer *buffer = &r_xprt->rx_buf;
1082 struct rpcrdma_req *req;
1084 req = kzalloc(sizeof(*req), GFP_KERNEL);
1086 return ERR_PTR(-ENOMEM);
1088 spin_lock(&buffer->rb_reqslock);
1089 list_add(&req->rl_all, &buffer->rb_allreqs);
1090 spin_unlock(&buffer->rb_reqslock);
1091 req->rl_buffer = &r_xprt->rx_buf;
1092 INIT_LIST_HEAD(&req->rl_registered);
1096 struct rpcrdma_rep *
1097 rpcrdma_create_rep(struct rpcrdma_xprt *r_xprt)
1099 struct rpcrdma_create_data_internal *cdata = &r_xprt->rx_data;
1100 struct rpcrdma_rep *rep;
1104 rep = kzalloc(sizeof(*rep), GFP_KERNEL);
1108 rep->rr_rdmabuf = rpcrdma_alloc_regbuf(cdata->inline_rsize,
1109 DMA_FROM_DEVICE, GFP_KERNEL);
1110 if (IS_ERR(rep->rr_rdmabuf)) {
1111 rc = PTR_ERR(rep->rr_rdmabuf);
1114 xdr_buf_init(&rep->rr_hdrbuf, rep->rr_rdmabuf->rg_base,
1115 rdmab_length(rep->rr_rdmabuf));
1117 rep->rr_cqe.done = rpcrdma_wc_receive;
1118 rep->rr_rxprt = r_xprt;
1119 INIT_WORK(&rep->rr_work, rpcrdma_deferred_completion);
1120 rep->rr_recv_wr.next = NULL;
1121 rep->rr_recv_wr.wr_cqe = &rep->rr_cqe;
1122 rep->rr_recv_wr.sg_list = &rep->rr_rdmabuf->rg_iov;
1123 rep->rr_recv_wr.num_sge = 1;
1133 rpcrdma_buffer_create(struct rpcrdma_xprt *r_xprt)
1135 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1138 buf->rb_max_requests = r_xprt->rx_data.max_requests;
1139 buf->rb_bc_srv_max_requests = 0;
1140 spin_lock_init(&buf->rb_mwlock);
1141 spin_lock_init(&buf->rb_lock);
1142 spin_lock_init(&buf->rb_recovery_lock);
1143 INIT_LIST_HEAD(&buf->rb_mws);
1144 INIT_LIST_HEAD(&buf->rb_all);
1145 INIT_LIST_HEAD(&buf->rb_stale_mrs);
1146 INIT_DELAYED_WORK(&buf->rb_refresh_worker,
1147 rpcrdma_mr_refresh_worker);
1148 INIT_DELAYED_WORK(&buf->rb_recovery_worker,
1149 rpcrdma_mr_recovery_worker);
1151 rpcrdma_create_mrs(r_xprt);
1153 INIT_LIST_HEAD(&buf->rb_send_bufs);
1154 INIT_LIST_HEAD(&buf->rb_allreqs);
1155 spin_lock_init(&buf->rb_reqslock);
1156 for (i = 0; i < buf->rb_max_requests; i++) {
1157 struct rpcrdma_req *req;
1159 req = rpcrdma_create_req(r_xprt);
1161 dprintk("RPC: %s: request buffer %d alloc"
1162 " failed\n", __func__, i);
1166 list_add(&req->rl_list, &buf->rb_send_bufs);
1169 INIT_LIST_HEAD(&buf->rb_recv_bufs);
1170 for (i = 0; i < buf->rb_max_requests + RPCRDMA_MAX_BC_REQUESTS; i++) {
1171 struct rpcrdma_rep *rep;
1173 rep = rpcrdma_create_rep(r_xprt);
1175 dprintk("RPC: %s: reply buffer %d alloc failed\n",
1180 list_add(&rep->rr_list, &buf->rb_recv_bufs);
1183 rc = rpcrdma_sendctxs_create(r_xprt);
1189 rpcrdma_buffer_destroy(buf);
1193 static struct rpcrdma_req *
1194 rpcrdma_buffer_get_req_locked(struct rpcrdma_buffer *buf)
1196 struct rpcrdma_req *req;
1198 req = list_first_entry(&buf->rb_send_bufs,
1199 struct rpcrdma_req, rl_list);
1200 list_del_init(&req->rl_list);
1204 static struct rpcrdma_rep *
1205 rpcrdma_buffer_get_rep_locked(struct rpcrdma_buffer *buf)
1207 struct rpcrdma_rep *rep;
1209 rep = list_first_entry(&buf->rb_recv_bufs,
1210 struct rpcrdma_rep, rr_list);
1211 list_del(&rep->rr_list);
1216 rpcrdma_destroy_rep(struct rpcrdma_rep *rep)
1218 rpcrdma_free_regbuf(rep->rr_rdmabuf);
1223 rpcrdma_destroy_req(struct rpcrdma_req *req)
1225 rpcrdma_free_regbuf(req->rl_recvbuf);
1226 rpcrdma_free_regbuf(req->rl_sendbuf);
1227 rpcrdma_free_regbuf(req->rl_rdmabuf);
1232 rpcrdma_destroy_mrs(struct rpcrdma_buffer *buf)
1234 struct rpcrdma_xprt *r_xprt = container_of(buf, struct rpcrdma_xprt,
1236 struct rpcrdma_ia *ia = rdmab_to_ia(buf);
1237 struct rpcrdma_mw *mw;
1241 spin_lock(&buf->rb_mwlock);
1242 while (!list_empty(&buf->rb_all)) {
1243 mw = list_entry(buf->rb_all.next, struct rpcrdma_mw, mw_all);
1244 list_del(&mw->mw_all);
1246 spin_unlock(&buf->rb_mwlock);
1247 ia->ri_ops->ro_release_mr(mw);
1249 spin_lock(&buf->rb_mwlock);
1251 spin_unlock(&buf->rb_mwlock);
1252 r_xprt->rx_stats.mrs_allocated = 0;
1254 dprintk("RPC: %s: released %u MRs\n", __func__, count);
1258 rpcrdma_buffer_destroy(struct rpcrdma_buffer *buf)
1260 cancel_delayed_work_sync(&buf->rb_recovery_worker);
1261 cancel_delayed_work_sync(&buf->rb_refresh_worker);
1263 rpcrdma_sendctxs_destroy(buf);
1265 while (!list_empty(&buf->rb_recv_bufs)) {
1266 struct rpcrdma_rep *rep;
1268 rep = rpcrdma_buffer_get_rep_locked(buf);
1269 rpcrdma_destroy_rep(rep);
1271 buf->rb_send_count = 0;
1273 spin_lock(&buf->rb_reqslock);
1274 while (!list_empty(&buf->rb_allreqs)) {
1275 struct rpcrdma_req *req;
1277 req = list_first_entry(&buf->rb_allreqs,
1278 struct rpcrdma_req, rl_all);
1279 list_del(&req->rl_all);
1281 spin_unlock(&buf->rb_reqslock);
1282 rpcrdma_destroy_req(req);
1283 spin_lock(&buf->rb_reqslock);
1285 spin_unlock(&buf->rb_reqslock);
1286 buf->rb_recv_count = 0;
1288 rpcrdma_destroy_mrs(buf);
1292 rpcrdma_get_mw(struct rpcrdma_xprt *r_xprt)
1294 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1295 struct rpcrdma_mw *mw = NULL;
1297 spin_lock(&buf->rb_mwlock);
1298 if (!list_empty(&buf->rb_mws))
1299 mw = rpcrdma_pop_mw(&buf->rb_mws);
1300 spin_unlock(&buf->rb_mwlock);
1308 dprintk("RPC: %s: no MWs available\n", __func__);
1309 if (r_xprt->rx_ep.rep_connected != -ENODEV)
1310 schedule_delayed_work(&buf->rb_refresh_worker, 0);
1312 /* Allow the reply handler and refresh worker to run */
1319 rpcrdma_put_mw(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mw *mw)
1321 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1323 spin_lock(&buf->rb_mwlock);
1324 rpcrdma_push_mw(mw, &buf->rb_mws);
1325 spin_unlock(&buf->rb_mwlock);
1328 static struct rpcrdma_rep *
1329 rpcrdma_buffer_get_rep(struct rpcrdma_buffer *buffers)
1331 /* If an RPC previously completed without a reply (say, a
1332 * credential problem or a soft timeout occurs) then hold off
1333 * on supplying more Receive buffers until the number of new
1334 * pending RPCs catches up to the number of posted Receives.
1336 if (unlikely(buffers->rb_send_count < buffers->rb_recv_count))
1339 if (unlikely(list_empty(&buffers->rb_recv_bufs)))
1341 buffers->rb_recv_count++;
1342 return rpcrdma_buffer_get_rep_locked(buffers);
1346 * Get a set of request/reply buffers.
1348 * Reply buffer (if available) is attached to send buffer upon return.
1350 struct rpcrdma_req *
1351 rpcrdma_buffer_get(struct rpcrdma_buffer *buffers)
1353 struct rpcrdma_req *req;
1355 spin_lock(&buffers->rb_lock);
1356 if (list_empty(&buffers->rb_send_bufs))
1358 buffers->rb_send_count++;
1359 req = rpcrdma_buffer_get_req_locked(buffers);
1360 req->rl_reply = rpcrdma_buffer_get_rep(buffers);
1361 spin_unlock(&buffers->rb_lock);
1365 spin_unlock(&buffers->rb_lock);
1366 pr_warn("RPC: %s: out of request buffers\n", __func__);
1371 * Put request/reply buffers back into pool.
1372 * Pre-decrement counter/array index.
1375 rpcrdma_buffer_put(struct rpcrdma_req *req)
1377 struct rpcrdma_buffer *buffers = req->rl_buffer;
1378 struct rpcrdma_rep *rep = req->rl_reply;
1380 req->rl_reply = NULL;
1382 spin_lock(&buffers->rb_lock);
1383 buffers->rb_send_count--;
1384 list_add_tail(&req->rl_list, &buffers->rb_send_bufs);
1386 buffers->rb_recv_count--;
1387 list_add_tail(&rep->rr_list, &buffers->rb_recv_bufs);
1389 spin_unlock(&buffers->rb_lock);
1393 * Recover reply buffers from pool.
1394 * This happens when recovering from disconnect.
1397 rpcrdma_recv_buffer_get(struct rpcrdma_req *req)
1399 struct rpcrdma_buffer *buffers = req->rl_buffer;
1401 spin_lock(&buffers->rb_lock);
1402 req->rl_reply = rpcrdma_buffer_get_rep(buffers);
1403 spin_unlock(&buffers->rb_lock);
1407 * Put reply buffers back into pool when not attached to
1408 * request. This happens in error conditions.
1411 rpcrdma_recv_buffer_put(struct rpcrdma_rep *rep)
1413 struct rpcrdma_buffer *buffers = &rep->rr_rxprt->rx_buf;
1415 spin_lock(&buffers->rb_lock);
1416 buffers->rb_recv_count--;
1417 list_add_tail(&rep->rr_list, &buffers->rb_recv_bufs);
1418 spin_unlock(&buffers->rb_lock);
1422 * rpcrdma_alloc_regbuf - allocate and DMA-map memory for SEND/RECV buffers
1423 * @size: size of buffer to be allocated, in bytes
1424 * @direction: direction of data movement
1427 * Returns an ERR_PTR, or a pointer to a regbuf, a buffer that
1428 * can be persistently DMA-mapped for I/O.
1430 * xprtrdma uses a regbuf for posting an outgoing RDMA SEND, or for
1431 * receiving the payload of RDMA RECV operations. During Long Calls
1432 * or Replies they may be registered externally via ro_map.
1434 struct rpcrdma_regbuf *
1435 rpcrdma_alloc_regbuf(size_t size, enum dma_data_direction direction,
1438 struct rpcrdma_regbuf *rb;
1440 rb = kmalloc(sizeof(*rb) + size, flags);
1442 return ERR_PTR(-ENOMEM);
1444 rb->rg_device = NULL;
1445 rb->rg_direction = direction;
1446 rb->rg_iov.length = size;
1452 * __rpcrdma_map_regbuf - DMA-map a regbuf
1453 * @ia: controlling rpcrdma_ia
1454 * @rb: regbuf to be mapped
1457 __rpcrdma_dma_map_regbuf(struct rpcrdma_ia *ia, struct rpcrdma_regbuf *rb)
1459 struct ib_device *device = ia->ri_device;
1461 if (rb->rg_direction == DMA_NONE)
1464 rb->rg_iov.addr = ib_dma_map_single(device,
1465 (void *)rb->rg_base,
1468 if (ib_dma_mapping_error(device, rdmab_addr(rb)))
1471 rb->rg_device = device;
1472 rb->rg_iov.lkey = ia->ri_pd->local_dma_lkey;
1477 rpcrdma_dma_unmap_regbuf(struct rpcrdma_regbuf *rb)
1479 if (!rpcrdma_regbuf_is_mapped(rb))
1482 ib_dma_unmap_single(rb->rg_device, rdmab_addr(rb),
1483 rdmab_length(rb), rb->rg_direction);
1484 rb->rg_device = NULL;
1488 * rpcrdma_free_regbuf - deregister and free registered buffer
1489 * @rb: regbuf to be deregistered and freed
1492 rpcrdma_free_regbuf(struct rpcrdma_regbuf *rb)
1497 rpcrdma_dma_unmap_regbuf(rb);
1502 * Prepost any receive buffer, then post send.
1504 * Receive buffer is donated to hardware, reclaimed upon recv completion.
1507 rpcrdma_ep_post(struct rpcrdma_ia *ia,
1508 struct rpcrdma_ep *ep,
1509 struct rpcrdma_req *req)
1511 struct ib_send_wr *send_wr = &req->rl_sendctx->sc_wr;
1512 struct ib_send_wr *send_wr_fail;
1515 if (req->rl_reply) {
1516 rc = rpcrdma_ep_post_recv(ia, req->rl_reply);
1519 req->rl_reply = NULL;
1522 dprintk("RPC: %s: posting %d s/g entries\n",
1523 __func__, send_wr->num_sge);
1525 if (!ep->rep_send_count ||
1526 test_bit(RPCRDMA_REQ_F_TX_RESOURCES, &req->rl_flags)) {
1527 send_wr->send_flags |= IB_SEND_SIGNALED;
1528 ep->rep_send_count = ep->rep_send_batch;
1530 send_wr->send_flags &= ~IB_SEND_SIGNALED;
1531 --ep->rep_send_count;
1533 rc = ib_post_send(ia->ri_id->qp, send_wr, &send_wr_fail);
1535 goto out_postsend_err;
1539 pr_err("rpcrdma: RDMA Send ib_post_send returned %i\n", rc);
1544 rpcrdma_ep_post_recv(struct rpcrdma_ia *ia,
1545 struct rpcrdma_rep *rep)
1547 struct ib_recv_wr *recv_wr_fail;
1550 if (!rpcrdma_dma_map_regbuf(ia, rep->rr_rdmabuf))
1552 rc = ib_post_recv(ia->ri_id->qp, &rep->rr_recv_wr, &recv_wr_fail);
1558 pr_err("rpcrdma: failed to DMA map the Receive buffer\n");
1562 pr_err("rpcrdma: ib_post_recv returned %i\n", rc);
1567 * rpcrdma_ep_post_extra_recv - Post buffers for incoming backchannel requests
1568 * @r_xprt: transport associated with these backchannel resources
1569 * @min_reqs: minimum number of incoming requests expected
1571 * Returns zero if all requested buffers were posted, or a negative errno.
1574 rpcrdma_ep_post_extra_recv(struct rpcrdma_xprt *r_xprt, unsigned int count)
1576 struct rpcrdma_buffer *buffers = &r_xprt->rx_buf;
1577 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
1578 struct rpcrdma_rep *rep;
1582 spin_lock(&buffers->rb_lock);
1583 if (list_empty(&buffers->rb_recv_bufs))
1585 rep = rpcrdma_buffer_get_rep_locked(buffers);
1586 spin_unlock(&buffers->rb_lock);
1588 rc = rpcrdma_ep_post_recv(ia, rep);
1596 spin_unlock(&buffers->rb_lock);
1597 pr_warn("%s: no extra receive buffers\n", __func__);
1601 rpcrdma_recv_buffer_put(rep);