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1/*
2 * Copyright (c) 2014-2017 Oracle. All rights reserved.
3 * Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
4 *
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
9 * license below:
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 *
15 * Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 *
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.
22 *
23 * Neither the name of the Network Appliance, Inc. nor the names of
24 * its contributors may be used to endorse or promote products
25 * derived from this software without specific prior written
26 * permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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.
39 */
40
41/*
42 * verbs.c
43 *
44 * Encapsulates the major functions managing:
45 * o adapters
46 * o endpoints
47 * o connections
48 * o buffer memory
49 */
50
51#include <linux/interrupt.h>
52#include <linux/slab.h>
53#include <linux/sunrpc/addr.h>
54#include <linux/sunrpc/svc_rdma.h>
55
56#include <asm-generic/barrier.h>
57#include <asm/bitops.h>
58
59#include <rdma/ib_cm.h>
60
61#include "xprt_rdma.h"
62
63/*
64 * Globals/Macros
65 */
66
67#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
68# define RPCDBG_FACILITY RPCDBG_TRANS
69#endif
70
71/*
72 * internal functions
73 */
74static void rpcrdma_mrs_create(struct rpcrdma_xprt *r_xprt);
75static void rpcrdma_mrs_destroy(struct rpcrdma_buffer *buf);
76static void rpcrdma_dma_unmap_regbuf(struct rpcrdma_regbuf *rb);
77
78struct workqueue_struct *rpcrdma_receive_wq __read_mostly;
79
80int
81rpcrdma_alloc_wq(void)
82{
83 struct workqueue_struct *recv_wq;
84
85 recv_wq = alloc_workqueue("xprtrdma_receive",
86 WQ_MEM_RECLAIM | WQ_HIGHPRI,
87 0);
88 if (!recv_wq)
89 return -ENOMEM;
90
91 rpcrdma_receive_wq = recv_wq;
92 return 0;
93}
94
95void
96rpcrdma_destroy_wq(void)
97{
98 struct workqueue_struct *wq;
99
100 if (rpcrdma_receive_wq) {
101 wq = rpcrdma_receive_wq;
102 rpcrdma_receive_wq = NULL;
103 destroy_workqueue(wq);
104 }
105}
106
107static void
108rpcrdma_qp_async_error_upcall(struct ib_event *event, void *context)
109{
110 struct rpcrdma_ep *ep = context;
111 struct rpcrdma_xprt *r_xprt = container_of(ep, struct rpcrdma_xprt,
112 rx_ep);
113
114 trace_xprtrdma_qp_error(r_xprt, event);
115 pr_err("rpcrdma: %s on device %s ep %p\n",
116 ib_event_msg(event->event), event->device->name, context);
117
118 if (ep->rep_connected == 1) {
119 ep->rep_connected = -EIO;
120 rpcrdma_conn_func(ep);
121 wake_up_all(&ep->rep_connect_wait);
122 }
123}
124
125/**
126 * rpcrdma_wc_send - Invoked by RDMA provider for each polled Send WC
127 * @cq: completion queue (ignored)
128 * @wc: completed WR
129 *
130 */
131static void
132rpcrdma_wc_send(struct ib_cq *cq, struct ib_wc *wc)
133{
134 struct ib_cqe *cqe = wc->wr_cqe;
135 struct rpcrdma_sendctx *sc =
136 container_of(cqe, struct rpcrdma_sendctx, sc_cqe);
137
138 /* WARNING: Only wr_cqe and status are reliable at this point */
139 trace_xprtrdma_wc_send(sc, wc);
140 if (wc->status != IB_WC_SUCCESS && wc->status != IB_WC_WR_FLUSH_ERR)
141 pr_err("rpcrdma: Send: %s (%u/0x%x)\n",
142 ib_wc_status_msg(wc->status),
143 wc->status, wc->vendor_err);
144
145 rpcrdma_sendctx_put_locked(sc);
146}
147
148/**
149 * rpcrdma_wc_receive - Invoked by RDMA provider for each polled Receive WC
150 * @cq: completion queue (ignored)
151 * @wc: completed WR
152 *
153 */
154static void
155rpcrdma_wc_receive(struct ib_cq *cq, struct ib_wc *wc)
156{
157 struct ib_cqe *cqe = wc->wr_cqe;
158 struct rpcrdma_rep *rep = container_of(cqe, struct rpcrdma_rep,
159 rr_cqe);
160
161 /* WARNING: Only wr_id and status are reliable at this point */
162 trace_xprtrdma_wc_receive(rep, wc);
163 if (wc->status != IB_WC_SUCCESS)
164 goto out_fail;
165
166 /* status == SUCCESS means all fields in wc are trustworthy */
167 rpcrdma_set_xdrlen(&rep->rr_hdrbuf, wc->byte_len);
168 rep->rr_wc_flags = wc->wc_flags;
169 rep->rr_inv_rkey = wc->ex.invalidate_rkey;
170
171 ib_dma_sync_single_for_cpu(rdmab_device(rep->rr_rdmabuf),
172 rdmab_addr(rep->rr_rdmabuf),
173 wc->byte_len, DMA_FROM_DEVICE);
174
175out_schedule:
176 rpcrdma_reply_handler(rep);
177 return;
178
179out_fail:
180 if (wc->status != IB_WC_WR_FLUSH_ERR)
181 pr_err("rpcrdma: Recv: %s (%u/0x%x)\n",
182 ib_wc_status_msg(wc->status),
183 wc->status, wc->vendor_err);
184 rpcrdma_set_xdrlen(&rep->rr_hdrbuf, 0);
185 goto out_schedule;
186}
187
188static void
189rpcrdma_update_connect_private(struct rpcrdma_xprt *r_xprt,
190 struct rdma_conn_param *param)
191{
192 struct rpcrdma_create_data_internal *cdata = &r_xprt->rx_data;
193 const struct rpcrdma_connect_private *pmsg = param->private_data;
194 unsigned int rsize, wsize;
195
196 /* Default settings for RPC-over-RDMA Version One */
197 r_xprt->rx_ia.ri_implicit_roundup = xprt_rdma_pad_optimize;
198 rsize = RPCRDMA_V1_DEF_INLINE_SIZE;
199 wsize = RPCRDMA_V1_DEF_INLINE_SIZE;
200
201 if (pmsg &&
202 pmsg->cp_magic == rpcrdma_cmp_magic &&
203 pmsg->cp_version == RPCRDMA_CMP_VERSION) {
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);
207 }
208
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);
216}
217
218static int
219rpcrdma_conn_upcall(struct rdma_cm_id *id, struct rdma_cm_event *event)
220{
221 struct rpcrdma_xprt *xprt = id->context;
222 struct rpcrdma_ia *ia = &xprt->rx_ia;
223 struct rpcrdma_ep *ep = &xprt->rx_ep;
224 int connstate = 0;
225
226 trace_xprtrdma_conn_upcall(xprt, event);
227 switch (event->event) {
228 case RDMA_CM_EVENT_ADDR_RESOLVED:
229 case RDMA_CM_EVENT_ROUTE_RESOLVED:
230 ia->ri_async_rc = 0;
231 complete(&ia->ri_done);
232 break;
233 case RDMA_CM_EVENT_ADDR_ERROR:
234 ia->ri_async_rc = -EHOSTUNREACH;
235 complete(&ia->ri_done);
236 break;
237 case RDMA_CM_EVENT_ROUTE_ERROR:
238 ia->ri_async_rc = -ENETUNREACH;
239 complete(&ia->ri_done);
240 break;
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_device->name,
245 rpcrdma_addrstr(xprt), rpcrdma_portstr(xprt));
246#endif
247 set_bit(RPCRDMA_IAF_REMOVING, &ia->ri_flags);
248 ep->rep_connected = -ENODEV;
249 xprt_force_disconnect(&xprt->rx_xprt);
250 wait_for_completion(&ia->ri_remove_done);
251
252 ia->ri_id = NULL;
253 ia->ri_device = NULL;
254 /* Return 1 to ensure the core destroys the id. */
255 return 1;
256 case RDMA_CM_EVENT_ESTABLISHED:
257 ++xprt->rx_xprt.connect_cookie;
258 connstate = 1;
259 rpcrdma_update_connect_private(xprt, &event->param.conn);
260 goto connected;
261 case RDMA_CM_EVENT_CONNECT_ERROR:
262 connstate = -ENOTCONN;
263 goto connected;
264 case RDMA_CM_EVENT_UNREACHABLE:
265 connstate = -ENETDOWN;
266 goto connected;
267 case RDMA_CM_EVENT_REJECTED:
268 dprintk("rpcrdma: connection to %s:%s rejected: %s\n",
269 rpcrdma_addrstr(xprt), rpcrdma_portstr(xprt),
270 rdma_reject_msg(id, event->status));
271 connstate = -ECONNREFUSED;
272 if (event->status == IB_CM_REJ_STALE_CONN)
273 connstate = -EAGAIN;
274 goto connected;
275 case RDMA_CM_EVENT_DISCONNECTED:
276 ++xprt->rx_xprt.connect_cookie;
277 connstate = -ECONNABORTED;
278connected:
279 xprt->rx_buf.rb_credits = 1;
280 ep->rep_connected = connstate;
281 rpcrdma_conn_func(ep);
282 wake_up_all(&ep->rep_connect_wait);
283 /*FALLTHROUGH*/
284 default:
285 dprintk("RPC: %s: %s:%s on %s/%s (ep 0x%p): %s\n",
286 __func__,
287 rpcrdma_addrstr(xprt), rpcrdma_portstr(xprt),
288 ia->ri_device->name, ia->ri_ops->ro_displayname,
289 ep, rdma_event_msg(event->event));
290 break;
291 }
292
293 return 0;
294}
295
296static struct rdma_cm_id *
297rpcrdma_create_id(struct rpcrdma_xprt *xprt, struct rpcrdma_ia *ia)
298{
299 unsigned long wtimeout = msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT) + 1;
300 struct rdma_cm_id *id;
301 int rc;
302
303 trace_xprtrdma_conn_start(xprt);
304
305 init_completion(&ia->ri_done);
306 init_completion(&ia->ri_remove_done);
307
308 id = rdma_create_id(&init_net, rpcrdma_conn_upcall, xprt, RDMA_PS_TCP,
309 IB_QPT_RC);
310 if (IS_ERR(id)) {
311 rc = PTR_ERR(id);
312 dprintk("RPC: %s: rdma_create_id() failed %i\n",
313 __func__, rc);
314 return id;
315 }
316
317 ia->ri_async_rc = -ETIMEDOUT;
318 rc = rdma_resolve_addr(id, NULL,
319 (struct sockaddr *)&xprt->rx_xprt.addr,
320 RDMA_RESOLVE_TIMEOUT);
321 if (rc) {
322 dprintk("RPC: %s: rdma_resolve_addr() failed %i\n",
323 __func__, rc);
324 goto out;
325 }
326 rc = wait_for_completion_interruptible_timeout(&ia->ri_done, wtimeout);
327 if (rc < 0) {
328 trace_xprtrdma_conn_tout(xprt);
329 goto out;
330 }
331
332 rc = ia->ri_async_rc;
333 if (rc)
334 goto out;
335
336 ia->ri_async_rc = -ETIMEDOUT;
337 rc = rdma_resolve_route(id, RDMA_RESOLVE_TIMEOUT);
338 if (rc) {
339 dprintk("RPC: %s: rdma_resolve_route() failed %i\n",
340 __func__, rc);
341 goto out;
342 }
343 rc = wait_for_completion_interruptible_timeout(&ia->ri_done, wtimeout);
344 if (rc < 0) {
345 trace_xprtrdma_conn_tout(xprt);
346 goto out;
347 }
348 rc = ia->ri_async_rc;
349 if (rc)
350 goto out;
351
352 return id;
353
354out:
355 rdma_destroy_id(id);
356 return ERR_PTR(rc);
357}
358
359/*
360 * Exported functions.
361 */
362
363/**
364 * rpcrdma_ia_open - Open and initialize an Interface Adapter.
365 * @xprt: transport with IA to (re)initialize
366 *
367 * Returns 0 on success, negative errno if an appropriate
368 * Interface Adapter could not be found and opened.
369 */
370int
371rpcrdma_ia_open(struct rpcrdma_xprt *xprt)
372{
373 struct rpcrdma_ia *ia = &xprt->rx_ia;
374 int rc;
375
376 ia->ri_id = rpcrdma_create_id(xprt, ia);
377 if (IS_ERR(ia->ri_id)) {
378 rc = PTR_ERR(ia->ri_id);
379 goto out_err;
380 }
381 ia->ri_device = ia->ri_id->device;
382
383 ia->ri_pd = ib_alloc_pd(ia->ri_device, 0);
384 if (IS_ERR(ia->ri_pd)) {
385 rc = PTR_ERR(ia->ri_pd);
386 pr_err("rpcrdma: ib_alloc_pd() returned %d\n", rc);
387 goto out_err;
388 }
389
390 switch (xprt_rdma_memreg_strategy) {
391 case RPCRDMA_FRWR:
392 if (frwr_is_supported(ia)) {
393 ia->ri_ops = &rpcrdma_frwr_memreg_ops;
394 break;
395 }
396 /*FALLTHROUGH*/
397 case RPCRDMA_MTHCAFMR:
398 if (fmr_is_supported(ia)) {
399 ia->ri_ops = &rpcrdma_fmr_memreg_ops;
400 break;
401 }
402 /*FALLTHROUGH*/
403 default:
404 pr_err("rpcrdma: Device %s does not support memreg mode %d\n",
405 ia->ri_device->name, xprt_rdma_memreg_strategy);
406 rc = -EINVAL;
407 goto out_err;
408 }
409
410 return 0;
411
412out_err:
413 rpcrdma_ia_close(ia);
414 return rc;
415}
416
417/**
418 * rpcrdma_ia_remove - Handle device driver unload
419 * @ia: interface adapter being removed
420 *
421 * Divest transport H/W resources associated with this adapter,
422 * but allow it to be restored later.
423 */
424void
425rpcrdma_ia_remove(struct rpcrdma_ia *ia)
426{
427 struct rpcrdma_xprt *r_xprt = container_of(ia, struct rpcrdma_xprt,
428 rx_ia);
429 struct rpcrdma_ep *ep = &r_xprt->rx_ep;
430 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
431 struct rpcrdma_req *req;
432 struct rpcrdma_rep *rep;
433
434 cancel_delayed_work_sync(&buf->rb_refresh_worker);
435
436 /* This is similar to rpcrdma_ep_destroy, but:
437 * - Don't cancel the connect worker.
438 * - Don't call rpcrdma_ep_disconnect, which waits
439 * for another conn upcall, which will deadlock.
440 * - rdma_disconnect is unneeded, the underlying
441 * connection is already gone.
442 */
443 if (ia->ri_id->qp) {
444 ib_drain_qp(ia->ri_id->qp);
445 rdma_destroy_qp(ia->ri_id);
446 ia->ri_id->qp = NULL;
447 }
448 ib_free_cq(ep->rep_attr.recv_cq);
449 ep->rep_attr.recv_cq = NULL;
450 ib_free_cq(ep->rep_attr.send_cq);
451 ep->rep_attr.send_cq = NULL;
452
453 /* The ULP is responsible for ensuring all DMA
454 * mappings and MRs are gone.
455 */
456 list_for_each_entry(rep, &buf->rb_recv_bufs, rr_list)
457 rpcrdma_dma_unmap_regbuf(rep->rr_rdmabuf);
458 list_for_each_entry(req, &buf->rb_allreqs, rl_all) {
459 rpcrdma_dma_unmap_regbuf(req->rl_rdmabuf);
460 rpcrdma_dma_unmap_regbuf(req->rl_sendbuf);
461 rpcrdma_dma_unmap_regbuf(req->rl_recvbuf);
462 }
463 rpcrdma_mrs_destroy(buf);
464 ib_dealloc_pd(ia->ri_pd);
465 ia->ri_pd = NULL;
466
467 /* Allow waiters to continue */
468 complete(&ia->ri_remove_done);
469
470 trace_xprtrdma_remove(r_xprt);
471}
472
473/**
474 * rpcrdma_ia_close - Clean up/close an IA.
475 * @ia: interface adapter to close
476 *
477 */
478void
479rpcrdma_ia_close(struct rpcrdma_ia *ia)
480{
481 if (ia->ri_id != NULL && !IS_ERR(ia->ri_id)) {
482 if (ia->ri_id->qp)
483 rdma_destroy_qp(ia->ri_id);
484 rdma_destroy_id(ia->ri_id);
485 }
486 ia->ri_id = NULL;
487 ia->ri_device = NULL;
488
489 /* If the pd is still busy, xprtrdma missed freeing a resource */
490 if (ia->ri_pd && !IS_ERR(ia->ri_pd))
491 ib_dealloc_pd(ia->ri_pd);
492 ia->ri_pd = NULL;
493}
494
495/*
496 * Create unconnected endpoint.
497 */
498int
499rpcrdma_ep_create(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia,
500 struct rpcrdma_create_data_internal *cdata)
501{
502 struct rpcrdma_connect_private *pmsg = &ep->rep_cm_private;
503 unsigned int max_qp_wr, max_sge;
504 struct ib_cq *sendcq, *recvcq;
505 int rc;
506
507 max_sge = min_t(unsigned int, ia->ri_device->attrs.max_sge,
508 RPCRDMA_MAX_SEND_SGES);
509 if (max_sge < RPCRDMA_MIN_SEND_SGES) {
510 pr_warn("rpcrdma: HCA provides only %d send SGEs\n", max_sge);
511 return -ENOMEM;
512 }
513 ia->ri_max_send_sges = max_sge;
514
515 if (ia->ri_device->attrs.max_qp_wr <= RPCRDMA_BACKWARD_WRS) {
516 dprintk("RPC: %s: insufficient wqe's available\n",
517 __func__);
518 return -ENOMEM;
519 }
520 max_qp_wr = ia->ri_device->attrs.max_qp_wr - RPCRDMA_BACKWARD_WRS - 1;
521
522 /* check provider's send/recv wr limits */
523 if (cdata->max_requests > max_qp_wr)
524 cdata->max_requests = max_qp_wr;
525
526 ep->rep_attr.event_handler = rpcrdma_qp_async_error_upcall;
527 ep->rep_attr.qp_context = ep;
528 ep->rep_attr.srq = NULL;
529 ep->rep_attr.cap.max_send_wr = cdata->max_requests;
530 ep->rep_attr.cap.max_send_wr += RPCRDMA_BACKWARD_WRS;
531 ep->rep_attr.cap.max_send_wr += 1; /* drain cqe */
532 rc = ia->ri_ops->ro_open(ia, ep, cdata);
533 if (rc)
534 return rc;
535 ep->rep_attr.cap.max_recv_wr = cdata->max_requests;
536 ep->rep_attr.cap.max_recv_wr += RPCRDMA_BACKWARD_WRS;
537 ep->rep_attr.cap.max_recv_wr += 1; /* drain cqe */
538 ep->rep_attr.cap.max_send_sge = max_sge;
539 ep->rep_attr.cap.max_recv_sge = 1;
540 ep->rep_attr.cap.max_inline_data = 0;
541 ep->rep_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
542 ep->rep_attr.qp_type = IB_QPT_RC;
543 ep->rep_attr.port_num = ~0;
544
545 dprintk("RPC: %s: requested max: dtos: send %d recv %d; "
546 "iovs: send %d recv %d\n",
547 __func__,
548 ep->rep_attr.cap.max_send_wr,
549 ep->rep_attr.cap.max_recv_wr,
550 ep->rep_attr.cap.max_send_sge,
551 ep->rep_attr.cap.max_recv_sge);
552
553 /* set trigger for requesting send completion */
554 ep->rep_send_batch = min_t(unsigned int, RPCRDMA_MAX_SEND_BATCH,
555 cdata->max_requests >> 2);
556 ep->rep_send_count = ep->rep_send_batch;
557 init_waitqueue_head(&ep->rep_connect_wait);
558 INIT_DELAYED_WORK(&ep->rep_connect_worker, rpcrdma_connect_worker);
559
560 sendcq = ib_alloc_cq(ia->ri_device, NULL,
561 ep->rep_attr.cap.max_send_wr + 1,
562 1, IB_POLL_WORKQUEUE);
563 if (IS_ERR(sendcq)) {
564 rc = PTR_ERR(sendcq);
565 dprintk("RPC: %s: failed to create send CQ: %i\n",
566 __func__, rc);
567 goto out1;
568 }
569
570 recvcq = ib_alloc_cq(ia->ri_device, NULL,
571 ep->rep_attr.cap.max_recv_wr + 1,
572 0, IB_POLL_WORKQUEUE);
573 if (IS_ERR(recvcq)) {
574 rc = PTR_ERR(recvcq);
575 dprintk("RPC: %s: failed to create recv CQ: %i\n",
576 __func__, rc);
577 goto out2;
578 }
579
580 ep->rep_attr.send_cq = sendcq;
581 ep->rep_attr.recv_cq = recvcq;
582
583 /* Initialize cma parameters */
584 memset(&ep->rep_remote_cma, 0, sizeof(ep->rep_remote_cma));
585
586 /* Prepare RDMA-CM private message */
587 pmsg->cp_magic = rpcrdma_cmp_magic;
588 pmsg->cp_version = RPCRDMA_CMP_VERSION;
589 pmsg->cp_flags |= ia->ri_ops->ro_send_w_inv_ok;
590 pmsg->cp_send_size = rpcrdma_encode_buffer_size(cdata->inline_wsize);
591 pmsg->cp_recv_size = rpcrdma_encode_buffer_size(cdata->inline_rsize);
592 ep->rep_remote_cma.private_data = pmsg;
593 ep->rep_remote_cma.private_data_len = sizeof(*pmsg);
594
595 /* Client offers RDMA Read but does not initiate */
596 ep->rep_remote_cma.initiator_depth = 0;
597 ep->rep_remote_cma.responder_resources =
598 min_t(int, U8_MAX, ia->ri_device->attrs.max_qp_rd_atom);
599
600 /* Limit transport retries so client can detect server
601 * GID changes quickly. RPC layer handles re-establishing
602 * transport connection and retransmission.
603 */
604 ep->rep_remote_cma.retry_count = 6;
605
606 /* RPC-over-RDMA handles its own flow control. In addition,
607 * make all RNR NAKs visible so we know that RPC-over-RDMA
608 * flow control is working correctly (no NAKs should be seen).
609 */
610 ep->rep_remote_cma.flow_control = 0;
611 ep->rep_remote_cma.rnr_retry_count = 0;
612
613 return 0;
614
615out2:
616 ib_free_cq(sendcq);
617out1:
618 return rc;
619}
620
621/*
622 * rpcrdma_ep_destroy
623 *
624 * Disconnect and destroy endpoint. After this, the only
625 * valid operations on the ep are to free it (if dynamically
626 * allocated) or re-create it.
627 */
628void
629rpcrdma_ep_destroy(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
630{
631 cancel_delayed_work_sync(&ep->rep_connect_worker);
632
633 if (ia->ri_id && ia->ri_id->qp) {
634 rpcrdma_ep_disconnect(ep, ia);
635 rdma_destroy_qp(ia->ri_id);
636 ia->ri_id->qp = NULL;
637 }
638
639 if (ep->rep_attr.recv_cq)
640 ib_free_cq(ep->rep_attr.recv_cq);
641 if (ep->rep_attr.send_cq)
642 ib_free_cq(ep->rep_attr.send_cq);
643}
644
645/* Re-establish a connection after a device removal event.
646 * Unlike a normal reconnection, a fresh PD and a new set
647 * of MRs and buffers is needed.
648 */
649static int
650rpcrdma_ep_recreate_xprt(struct rpcrdma_xprt *r_xprt,
651 struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
652{
653 int rc, err;
654
655 trace_xprtrdma_reinsert(r_xprt);
656
657 rc = -EHOSTUNREACH;
658 if (rpcrdma_ia_open(r_xprt))
659 goto out1;
660
661 rc = -ENOMEM;
662 err = rpcrdma_ep_create(ep, ia, &r_xprt->rx_data);
663 if (err) {
664 pr_err("rpcrdma: rpcrdma_ep_create returned %d\n", err);
665 goto out2;
666 }
667
668 rc = -ENETUNREACH;
669 err = rdma_create_qp(ia->ri_id, ia->ri_pd, &ep->rep_attr);
670 if (err) {
671 pr_err("rpcrdma: rdma_create_qp returned %d\n", err);
672 goto out3;
673 }
674
675 rpcrdma_mrs_create(r_xprt);
676 return 0;
677
678out3:
679 rpcrdma_ep_destroy(ep, ia);
680out2:
681 rpcrdma_ia_close(ia);
682out1:
683 return rc;
684}
685
686static int
687rpcrdma_ep_reconnect(struct rpcrdma_xprt *r_xprt, struct rpcrdma_ep *ep,
688 struct rpcrdma_ia *ia)
689{
690 struct rdma_cm_id *id, *old;
691 int err, rc;
692
693 trace_xprtrdma_reconnect(r_xprt);
694
695 rpcrdma_ep_disconnect(ep, ia);
696
697 rc = -EHOSTUNREACH;
698 id = rpcrdma_create_id(r_xprt, ia);
699 if (IS_ERR(id))
700 goto out;
701
702 /* As long as the new ID points to the same device as the
703 * old ID, we can reuse the transport's existing PD and all
704 * previously allocated MRs. Also, the same device means
705 * the transport's previous DMA mappings are still valid.
706 *
707 * This is a sanity check only. There should be no way these
708 * point to two different devices here.
709 */
710 old = id;
711 rc = -ENETUNREACH;
712 if (ia->ri_device != id->device) {
713 pr_err("rpcrdma: can't reconnect on different device!\n");
714 goto out_destroy;
715 }
716
717 err = rdma_create_qp(id, ia->ri_pd, &ep->rep_attr);
718 if (err) {
719 dprintk("RPC: %s: rdma_create_qp returned %d\n",
720 __func__, err);
721 goto out_destroy;
722 }
723
724 /* Atomically replace the transport's ID and QP. */
725 rc = 0;
726 old = ia->ri_id;
727 ia->ri_id = id;
728 rdma_destroy_qp(old);
729
730out_destroy:
731 rdma_destroy_id(old);
732out:
733 return rc;
734}
735
736/*
737 * Connect unconnected endpoint.
738 */
739int
740rpcrdma_ep_connect(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
741{
742 struct rpcrdma_xprt *r_xprt = container_of(ia, struct rpcrdma_xprt,
743 rx_ia);
744 unsigned int extras;
745 int rc;
746
747retry:
748 switch (ep->rep_connected) {
749 case 0:
750 dprintk("RPC: %s: connecting...\n", __func__);
751 rc = rdma_create_qp(ia->ri_id, ia->ri_pd, &ep->rep_attr);
752 if (rc) {
753 dprintk("RPC: %s: rdma_create_qp failed %i\n",
754 __func__, rc);
755 rc = -ENETUNREACH;
756 goto out_noupdate;
757 }
758 break;
759 case -ENODEV:
760 rc = rpcrdma_ep_recreate_xprt(r_xprt, ep, ia);
761 if (rc)
762 goto out_noupdate;
763 break;
764 default:
765 rc = rpcrdma_ep_reconnect(r_xprt, ep, ia);
766 if (rc)
767 goto out;
768 }
769
770 ep->rep_connected = 0;
771
772 rc = rdma_connect(ia->ri_id, &ep->rep_remote_cma);
773 if (rc) {
774 dprintk("RPC: %s: rdma_connect() failed with %i\n",
775 __func__, rc);
776 goto out;
777 }
778
779 wait_event_interruptible(ep->rep_connect_wait, ep->rep_connected != 0);
780 if (ep->rep_connected <= 0) {
781 if (ep->rep_connected == -EAGAIN)
782 goto retry;
783 rc = ep->rep_connected;
784 goto out;
785 }
786
787 dprintk("RPC: %s: connected\n", __func__);
788 extras = r_xprt->rx_buf.rb_bc_srv_max_requests;
789 if (extras)
790 rpcrdma_ep_post_extra_recv(r_xprt, extras);
791
792out:
793 if (rc)
794 ep->rep_connected = rc;
795
796out_noupdate:
797 return rc;
798}
799
800/*
801 * rpcrdma_ep_disconnect
802 *
803 * This is separate from destroy to facilitate the ability
804 * to reconnect without recreating the endpoint.
805 *
806 * This call is not reentrant, and must not be made in parallel
807 * on the same endpoint.
808 */
809void
810rpcrdma_ep_disconnect(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
811{
812 int rc;
813
814 rc = rdma_disconnect(ia->ri_id);
815 if (!rc)
816 /* returns without wait if not connected */
817 wait_event_interruptible(ep->rep_connect_wait,
818 ep->rep_connected != 1);
819 else
820 ep->rep_connected = rc;
821 trace_xprtrdma_disconnect(container_of(ep, struct rpcrdma_xprt,
822 rx_ep), rc);
823
824 ib_drain_qp(ia->ri_id->qp);
825}
826
827/* Fixed-size circular FIFO queue. This implementation is wait-free and
828 * lock-free.
829 *
830 * Consumer is the code path that posts Sends. This path dequeues a
831 * sendctx for use by a Send operation. Multiple consumer threads
832 * are serialized by the RPC transport lock, which allows only one
833 * ->send_request call at a time.
834 *
835 * Producer is the code path that handles Send completions. This path
836 * enqueues a sendctx that has been completed. Multiple producer
837 * threads are serialized by the ib_poll_cq() function.
838 */
839
840/* rpcrdma_sendctxs_destroy() assumes caller has already quiesced
841 * queue activity, and ib_drain_qp has flushed all remaining Send
842 * requests.
843 */
844static void rpcrdma_sendctxs_destroy(struct rpcrdma_buffer *buf)
845{
846 unsigned long i;
847
848 for (i = 0; i <= buf->rb_sc_last; i++)
849 kfree(buf->rb_sc_ctxs[i]);
850 kfree(buf->rb_sc_ctxs);
851}
852
853static struct rpcrdma_sendctx *rpcrdma_sendctx_create(struct rpcrdma_ia *ia)
854{
855 struct rpcrdma_sendctx *sc;
856
857 sc = kzalloc(sizeof(*sc) +
858 ia->ri_max_send_sges * sizeof(struct ib_sge),
859 GFP_KERNEL);
860 if (!sc)
861 return NULL;
862
863 sc->sc_wr.wr_cqe = &sc->sc_cqe;
864 sc->sc_wr.sg_list = sc->sc_sges;
865 sc->sc_wr.opcode = IB_WR_SEND;
866 sc->sc_cqe.done = rpcrdma_wc_send;
867 return sc;
868}
869
870static int rpcrdma_sendctxs_create(struct rpcrdma_xprt *r_xprt)
871{
872 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
873 struct rpcrdma_sendctx *sc;
874 unsigned long i;
875
876 /* Maximum number of concurrent outstanding Send WRs. Capping
877 * the circular queue size stops Send Queue overflow by causing
878 * the ->send_request call to fail temporarily before too many
879 * Sends are posted.
880 */
881 i = buf->rb_max_requests + RPCRDMA_MAX_BC_REQUESTS;
882 dprintk("RPC: %s: allocating %lu send_ctxs\n", __func__, i);
883 buf->rb_sc_ctxs = kcalloc(i, sizeof(sc), GFP_KERNEL);
884 if (!buf->rb_sc_ctxs)
885 return -ENOMEM;
886
887 buf->rb_sc_last = i - 1;
888 for (i = 0; i <= buf->rb_sc_last; i++) {
889 sc = rpcrdma_sendctx_create(&r_xprt->rx_ia);
890 if (!sc)
891 goto out_destroy;
892
893 sc->sc_xprt = r_xprt;
894 buf->rb_sc_ctxs[i] = sc;
895 }
896
897 return 0;
898
899out_destroy:
900 rpcrdma_sendctxs_destroy(buf);
901 return -ENOMEM;
902}
903
904/* The sendctx queue is not guaranteed to have a size that is a
905 * power of two, thus the helpers in circ_buf.h cannot be used.
906 * The other option is to use modulus (%), which can be expensive.
907 */
908static unsigned long rpcrdma_sendctx_next(struct rpcrdma_buffer *buf,
909 unsigned long item)
910{
911 return likely(item < buf->rb_sc_last) ? item + 1 : 0;
912}
913
914/**
915 * rpcrdma_sendctx_get_locked - Acquire a send context
916 * @buf: transport buffers from which to acquire an unused context
917 *
918 * Returns pointer to a free send completion context; or NULL if
919 * the queue is empty.
920 *
921 * Usage: Called to acquire an SGE array before preparing a Send WR.
922 *
923 * The caller serializes calls to this function (per rpcrdma_buffer),
924 * and provides an effective memory barrier that flushes the new value
925 * of rb_sc_head.
926 */
927struct rpcrdma_sendctx *rpcrdma_sendctx_get_locked(struct rpcrdma_buffer *buf)
928{
929 struct rpcrdma_xprt *r_xprt;
930 struct rpcrdma_sendctx *sc;
931 unsigned long next_head;
932
933 next_head = rpcrdma_sendctx_next(buf, buf->rb_sc_head);
934
935 if (next_head == READ_ONCE(buf->rb_sc_tail))
936 goto out_emptyq;
937
938 /* ORDER: item must be accessed _before_ head is updated */
939 sc = buf->rb_sc_ctxs[next_head];
940
941 /* Releasing the lock in the caller acts as a memory
942 * barrier that flushes rb_sc_head.
943 */
944 buf->rb_sc_head = next_head;
945
946 return sc;
947
948out_emptyq:
949 /* The queue is "empty" if there have not been enough Send
950 * completions recently. This is a sign the Send Queue is
951 * backing up. Cause the caller to pause and try again.
952 */
953 dprintk("RPC: %s: empty sendctx queue\n", __func__);
954 r_xprt = container_of(buf, struct rpcrdma_xprt, rx_buf);
955 r_xprt->rx_stats.empty_sendctx_q++;
956 return NULL;
957}
958
959/**
960 * rpcrdma_sendctx_put_locked - Release a send context
961 * @sc: send context to release
962 *
963 * Usage: Called from Send completion to return a sendctxt
964 * to the queue.
965 *
966 * The caller serializes calls to this function (per rpcrdma_buffer).
967 */
968void rpcrdma_sendctx_put_locked(struct rpcrdma_sendctx *sc)
969{
970 struct rpcrdma_buffer *buf = &sc->sc_xprt->rx_buf;
971 unsigned long next_tail;
972
973 /* Unmap SGEs of previously completed by unsignaled
974 * Sends by walking up the queue until @sc is found.
975 */
976 next_tail = buf->rb_sc_tail;
977 do {
978 next_tail = rpcrdma_sendctx_next(buf, next_tail);
979
980 /* ORDER: item must be accessed _before_ tail is updated */
981 rpcrdma_unmap_sendctx(buf->rb_sc_ctxs[next_tail]);
982
983 } while (buf->rb_sc_ctxs[next_tail] != sc);
984
985 /* Paired with READ_ONCE */
986 smp_store_release(&buf->rb_sc_tail, next_tail);
987}
988
989static void
990rpcrdma_mr_recovery_worker(struct work_struct *work)
991{
992 struct rpcrdma_buffer *buf = container_of(work, struct rpcrdma_buffer,
993 rb_recovery_worker.work);
994 struct rpcrdma_mr *mr;
995
996 spin_lock(&buf->rb_recovery_lock);
997 while (!list_empty(&buf->rb_stale_mrs)) {
998 mr = rpcrdma_mr_pop(&buf->rb_stale_mrs);
999 spin_unlock(&buf->rb_recovery_lock);
1000
1001 trace_xprtrdma_recover_mr(mr);
1002 mr->mr_xprt->rx_ia.ri_ops->ro_recover_mr(mr);
1003
1004 spin_lock(&buf->rb_recovery_lock);
1005 }
1006 spin_unlock(&buf->rb_recovery_lock);
1007}
1008
1009void
1010rpcrdma_mr_defer_recovery(struct rpcrdma_mr *mr)
1011{
1012 struct rpcrdma_xprt *r_xprt = mr->mr_xprt;
1013 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1014
1015 spin_lock(&buf->rb_recovery_lock);
1016 rpcrdma_mr_push(mr, &buf->rb_stale_mrs);
1017 spin_unlock(&buf->rb_recovery_lock);
1018
1019 schedule_delayed_work(&buf->rb_recovery_worker, 0);
1020}
1021
1022static void
1023rpcrdma_mrs_create(struct rpcrdma_xprt *r_xprt)
1024{
1025 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1026 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
1027 unsigned int count;
1028 LIST_HEAD(free);
1029 LIST_HEAD(all);
1030
1031 for (count = 0; count < 3; count++) {
1032 struct rpcrdma_mr *mr;
1033 int rc;
1034
1035 mr = kzalloc(sizeof(*mr), GFP_KERNEL);
1036 if (!mr)
1037 break;
1038
1039 rc = ia->ri_ops->ro_init_mr(ia, mr);
1040 if (rc) {
1041 kfree(mr);
1042 break;
1043 }
1044
1045 mr->mr_xprt = r_xprt;
1046
1047 list_add(&mr->mr_list, &free);
1048 list_add(&mr->mr_all, &all);
1049 }
1050
1051 spin_lock(&buf->rb_mrlock);
1052 list_splice(&free, &buf->rb_mrs);
1053 list_splice(&all, &buf->rb_all);
1054 r_xprt->rx_stats.mrs_allocated += count;
1055 spin_unlock(&buf->rb_mrlock);
1056 trace_xprtrdma_createmrs(r_xprt, count);
1057
1058 xprt_write_space(&r_xprt->rx_xprt);
1059}
1060
1061static void
1062rpcrdma_mr_refresh_worker(struct work_struct *work)
1063{
1064 struct rpcrdma_buffer *buf = container_of(work, struct rpcrdma_buffer,
1065 rb_refresh_worker.work);
1066 struct rpcrdma_xprt *r_xprt = container_of(buf, struct rpcrdma_xprt,
1067 rx_buf);
1068
1069 rpcrdma_mrs_create(r_xprt);
1070}
1071
1072struct rpcrdma_req *
1073rpcrdma_create_req(struct rpcrdma_xprt *r_xprt)
1074{
1075 struct rpcrdma_buffer *buffer = &r_xprt->rx_buf;
1076 struct rpcrdma_regbuf *rb;
1077 struct rpcrdma_req *req;
1078
1079 req = kzalloc(sizeof(*req), GFP_KERNEL);
1080 if (req == NULL)
1081 return ERR_PTR(-ENOMEM);
1082
1083 rb = rpcrdma_alloc_regbuf(RPCRDMA_HDRBUF_SIZE,
1084 DMA_TO_DEVICE, GFP_KERNEL);
1085 if (IS_ERR(rb)) {
1086 kfree(req);
1087 return ERR_PTR(-ENOMEM);
1088 }
1089 req->rl_rdmabuf = rb;
1090 xdr_buf_init(&req->rl_hdrbuf, rb->rg_base, rdmab_length(rb));
1091 req->rl_buffer = buffer;
1092 INIT_LIST_HEAD(&req->rl_registered);
1093
1094 spin_lock(&buffer->rb_reqslock);
1095 list_add(&req->rl_all, &buffer->rb_allreqs);
1096 spin_unlock(&buffer->rb_reqslock);
1097 return req;
1098}
1099
1100/**
1101 * rpcrdma_create_rep - Allocate an rpcrdma_rep object
1102 * @r_xprt: controlling transport
1103 *
1104 * Returns 0 on success or a negative errno on failure.
1105 */
1106int
1107rpcrdma_create_rep(struct rpcrdma_xprt *r_xprt)
1108{
1109 struct rpcrdma_create_data_internal *cdata = &r_xprt->rx_data;
1110 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1111 struct rpcrdma_rep *rep;
1112 int rc;
1113
1114 rc = -ENOMEM;
1115 rep = kzalloc(sizeof(*rep), GFP_KERNEL);
1116 if (rep == NULL)
1117 goto out;
1118
1119 rep->rr_rdmabuf = rpcrdma_alloc_regbuf(cdata->inline_rsize,
1120 DMA_FROM_DEVICE, GFP_KERNEL);
1121 if (IS_ERR(rep->rr_rdmabuf)) {
1122 rc = PTR_ERR(rep->rr_rdmabuf);
1123 goto out_free;
1124 }
1125 xdr_buf_init(&rep->rr_hdrbuf, rep->rr_rdmabuf->rg_base,
1126 rdmab_length(rep->rr_rdmabuf));
1127
1128 rep->rr_cqe.done = rpcrdma_wc_receive;
1129 rep->rr_rxprt = r_xprt;
1130 INIT_WORK(&rep->rr_work, rpcrdma_deferred_completion);
1131 rep->rr_recv_wr.next = NULL;
1132 rep->rr_recv_wr.wr_cqe = &rep->rr_cqe;
1133 rep->rr_recv_wr.sg_list = &rep->rr_rdmabuf->rg_iov;
1134 rep->rr_recv_wr.num_sge = 1;
1135
1136 spin_lock(&buf->rb_lock);
1137 list_add(&rep->rr_list, &buf->rb_recv_bufs);
1138 spin_unlock(&buf->rb_lock);
1139 return 0;
1140
1141out_free:
1142 kfree(rep);
1143out:
1144 dprintk("RPC: %s: reply buffer %d alloc failed\n",
1145 __func__, rc);
1146 return rc;
1147}
1148
1149int
1150rpcrdma_buffer_create(struct rpcrdma_xprt *r_xprt)
1151{
1152 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1153 int i, rc;
1154
1155 buf->rb_max_requests = r_xprt->rx_data.max_requests;
1156 buf->rb_bc_srv_max_requests = 0;
1157 spin_lock_init(&buf->rb_mrlock);
1158 spin_lock_init(&buf->rb_lock);
1159 spin_lock_init(&buf->rb_recovery_lock);
1160 INIT_LIST_HEAD(&buf->rb_mrs);
1161 INIT_LIST_HEAD(&buf->rb_all);
1162 INIT_LIST_HEAD(&buf->rb_stale_mrs);
1163 INIT_DELAYED_WORK(&buf->rb_refresh_worker,
1164 rpcrdma_mr_refresh_worker);
1165 INIT_DELAYED_WORK(&buf->rb_recovery_worker,
1166 rpcrdma_mr_recovery_worker);
1167
1168 rpcrdma_mrs_create(r_xprt);
1169
1170 INIT_LIST_HEAD(&buf->rb_send_bufs);
1171 INIT_LIST_HEAD(&buf->rb_allreqs);
1172 spin_lock_init(&buf->rb_reqslock);
1173 for (i = 0; i < buf->rb_max_requests; i++) {
1174 struct rpcrdma_req *req;
1175
1176 req = rpcrdma_create_req(r_xprt);
1177 if (IS_ERR(req)) {
1178 dprintk("RPC: %s: request buffer %d alloc"
1179 " failed\n", __func__, i);
1180 rc = PTR_ERR(req);
1181 goto out;
1182 }
1183 list_add(&req->rl_list, &buf->rb_send_bufs);
1184 }
1185
1186 INIT_LIST_HEAD(&buf->rb_recv_bufs);
1187 for (i = 0; i <= buf->rb_max_requests; i++) {
1188 rc = rpcrdma_create_rep(r_xprt);
1189 if (rc)
1190 goto out;
1191 }
1192
1193 rc = rpcrdma_sendctxs_create(r_xprt);
1194 if (rc)
1195 goto out;
1196
1197 return 0;
1198out:
1199 rpcrdma_buffer_destroy(buf);
1200 return rc;
1201}
1202
1203static struct rpcrdma_req *
1204rpcrdma_buffer_get_req_locked(struct rpcrdma_buffer *buf)
1205{
1206 struct rpcrdma_req *req;
1207
1208 req = list_first_entry(&buf->rb_send_bufs,
1209 struct rpcrdma_req, rl_list);
1210 list_del_init(&req->rl_list);
1211 return req;
1212}
1213
1214static struct rpcrdma_rep *
1215rpcrdma_buffer_get_rep_locked(struct rpcrdma_buffer *buf)
1216{
1217 struct rpcrdma_rep *rep;
1218
1219 rep = list_first_entry(&buf->rb_recv_bufs,
1220 struct rpcrdma_rep, rr_list);
1221 list_del(&rep->rr_list);
1222 return rep;
1223}
1224
1225static void
1226rpcrdma_destroy_rep(struct rpcrdma_rep *rep)
1227{
1228 rpcrdma_free_regbuf(rep->rr_rdmabuf);
1229 kfree(rep);
1230}
1231
1232void
1233rpcrdma_destroy_req(struct rpcrdma_req *req)
1234{
1235 rpcrdma_free_regbuf(req->rl_recvbuf);
1236 rpcrdma_free_regbuf(req->rl_sendbuf);
1237 rpcrdma_free_regbuf(req->rl_rdmabuf);
1238 kfree(req);
1239}
1240
1241static void
1242rpcrdma_mrs_destroy(struct rpcrdma_buffer *buf)
1243{
1244 struct rpcrdma_xprt *r_xprt = container_of(buf, struct rpcrdma_xprt,
1245 rx_buf);
1246 struct rpcrdma_ia *ia = rdmab_to_ia(buf);
1247 struct rpcrdma_mr *mr;
1248 unsigned int count;
1249
1250 count = 0;
1251 spin_lock(&buf->rb_mrlock);
1252 while (!list_empty(&buf->rb_all)) {
1253 mr = list_entry(buf->rb_all.next, struct rpcrdma_mr, mr_all);
1254 list_del(&mr->mr_all);
1255
1256 spin_unlock(&buf->rb_mrlock);
1257
1258 /* Ensure MW is not on any rl_registered list */
1259 if (!list_empty(&mr->mr_list))
1260 list_del(&mr->mr_list);
1261
1262 ia->ri_ops->ro_release_mr(mr);
1263 count++;
1264 spin_lock(&buf->rb_mrlock);
1265 }
1266 spin_unlock(&buf->rb_mrlock);
1267 r_xprt->rx_stats.mrs_allocated = 0;
1268
1269 dprintk("RPC: %s: released %u MRs\n", __func__, count);
1270}
1271
1272void
1273rpcrdma_buffer_destroy(struct rpcrdma_buffer *buf)
1274{
1275 cancel_delayed_work_sync(&buf->rb_recovery_worker);
1276 cancel_delayed_work_sync(&buf->rb_refresh_worker);
1277
1278 rpcrdma_sendctxs_destroy(buf);
1279
1280 while (!list_empty(&buf->rb_recv_bufs)) {
1281 struct rpcrdma_rep *rep;
1282
1283 rep = rpcrdma_buffer_get_rep_locked(buf);
1284 rpcrdma_destroy_rep(rep);
1285 }
1286 buf->rb_send_count = 0;
1287
1288 spin_lock(&buf->rb_reqslock);
1289 while (!list_empty(&buf->rb_allreqs)) {
1290 struct rpcrdma_req *req;
1291
1292 req = list_first_entry(&buf->rb_allreqs,
1293 struct rpcrdma_req, rl_all);
1294 list_del(&req->rl_all);
1295
1296 spin_unlock(&buf->rb_reqslock);
1297 rpcrdma_destroy_req(req);
1298 spin_lock(&buf->rb_reqslock);
1299 }
1300 spin_unlock(&buf->rb_reqslock);
1301 buf->rb_recv_count = 0;
1302
1303 rpcrdma_mrs_destroy(buf);
1304}
1305
1306/**
1307 * rpcrdma_mr_get - Allocate an rpcrdma_mr object
1308 * @r_xprt: controlling transport
1309 *
1310 * Returns an initialized rpcrdma_mr or NULL if no free
1311 * rpcrdma_mr objects are available.
1312 */
1313struct rpcrdma_mr *
1314rpcrdma_mr_get(struct rpcrdma_xprt *r_xprt)
1315{
1316 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
1317 struct rpcrdma_mr *mr = NULL;
1318
1319 spin_lock(&buf->rb_mrlock);
1320 if (!list_empty(&buf->rb_mrs))
1321 mr = rpcrdma_mr_pop(&buf->rb_mrs);
1322 spin_unlock(&buf->rb_mrlock);
1323
1324 if (!mr)
1325 goto out_nomrs;
1326 return mr;
1327
1328out_nomrs:
1329 trace_xprtrdma_nomrs(r_xprt);
1330 if (r_xprt->rx_ep.rep_connected != -ENODEV)
1331 schedule_delayed_work(&buf->rb_refresh_worker, 0);
1332
1333 /* Allow the reply handler and refresh worker to run */
1334 cond_resched();
1335
1336 return NULL;
1337}
1338
1339static void
1340__rpcrdma_mr_put(struct rpcrdma_buffer *buf, struct rpcrdma_mr *mr)
1341{
1342 spin_lock(&buf->rb_mrlock);
1343 rpcrdma_mr_push(mr, &buf->rb_mrs);
1344 spin_unlock(&buf->rb_mrlock);
1345}
1346
1347/**
1348 * rpcrdma_mr_put - Release an rpcrdma_mr object
1349 * @mr: object to release
1350 *
1351 */
1352void
1353rpcrdma_mr_put(struct rpcrdma_mr *mr)
1354{
1355 __rpcrdma_mr_put(&mr->mr_xprt->rx_buf, mr);
1356}
1357
1358/**
1359 * rpcrdma_mr_unmap_and_put - DMA unmap an MR and release it
1360 * @mr: object to release
1361 *
1362 */
1363void
1364rpcrdma_mr_unmap_and_put(struct rpcrdma_mr *mr)
1365{
1366 struct rpcrdma_xprt *r_xprt = mr->mr_xprt;
1367
1368 trace_xprtrdma_dma_unmap(mr);
1369 ib_dma_unmap_sg(r_xprt->rx_ia.ri_device,
1370 mr->mr_sg, mr->mr_nents, mr->mr_dir);
1371 __rpcrdma_mr_put(&r_xprt->rx_buf, mr);
1372}
1373
1374static struct rpcrdma_rep *
1375rpcrdma_buffer_get_rep(struct rpcrdma_buffer *buffers)
1376{
1377 /* If an RPC previously completed without a reply (say, a
1378 * credential problem or a soft timeout occurs) then hold off
1379 * on supplying more Receive buffers until the number of new
1380 * pending RPCs catches up to the number of posted Receives.
1381 */
1382 if (unlikely(buffers->rb_send_count < buffers->rb_recv_count))
1383 return NULL;
1384
1385 if (unlikely(list_empty(&buffers->rb_recv_bufs)))
1386 return NULL;
1387 buffers->rb_recv_count++;
1388 return rpcrdma_buffer_get_rep_locked(buffers);
1389}
1390
1391/*
1392 * Get a set of request/reply buffers.
1393 *
1394 * Reply buffer (if available) is attached to send buffer upon return.
1395 */
1396struct rpcrdma_req *
1397rpcrdma_buffer_get(struct rpcrdma_buffer *buffers)
1398{
1399 struct rpcrdma_req *req;
1400
1401 spin_lock(&buffers->rb_lock);
1402 if (list_empty(&buffers->rb_send_bufs))
1403 goto out_reqbuf;
1404 buffers->rb_send_count++;
1405 req = rpcrdma_buffer_get_req_locked(buffers);
1406 req->rl_reply = rpcrdma_buffer_get_rep(buffers);
1407 spin_unlock(&buffers->rb_lock);
1408
1409 return req;
1410
1411out_reqbuf:
1412 spin_unlock(&buffers->rb_lock);
1413 return NULL;
1414}
1415
1416/*
1417 * Put request/reply buffers back into pool.
1418 * Pre-decrement counter/array index.
1419 */
1420void
1421rpcrdma_buffer_put(struct rpcrdma_req *req)
1422{
1423 struct rpcrdma_buffer *buffers = req->rl_buffer;
1424 struct rpcrdma_rep *rep = req->rl_reply;
1425
1426 req->rl_reply = NULL;
1427
1428 spin_lock(&buffers->rb_lock);
1429 buffers->rb_send_count--;
1430 list_add_tail(&req->rl_list, &buffers->rb_send_bufs);
1431 if (rep) {
1432 buffers->rb_recv_count--;
1433 list_add_tail(&rep->rr_list, &buffers->rb_recv_bufs);
1434 }
1435 spin_unlock(&buffers->rb_lock);
1436}
1437
1438/*
1439 * Recover reply buffers from pool.
1440 * This happens when recovering from disconnect.
1441 */
1442void
1443rpcrdma_recv_buffer_get(struct rpcrdma_req *req)
1444{
1445 struct rpcrdma_buffer *buffers = req->rl_buffer;
1446
1447 spin_lock(&buffers->rb_lock);
1448 req->rl_reply = rpcrdma_buffer_get_rep(buffers);
1449 spin_unlock(&buffers->rb_lock);
1450}
1451
1452/*
1453 * Put reply buffers back into pool when not attached to
1454 * request. This happens in error conditions.
1455 */
1456void
1457rpcrdma_recv_buffer_put(struct rpcrdma_rep *rep)
1458{
1459 struct rpcrdma_buffer *buffers = &rep->rr_rxprt->rx_buf;
1460
1461 spin_lock(&buffers->rb_lock);
1462 buffers->rb_recv_count--;
1463 list_add_tail(&rep->rr_list, &buffers->rb_recv_bufs);
1464 spin_unlock(&buffers->rb_lock);
1465}
1466
1467/**
1468 * rpcrdma_alloc_regbuf - allocate and DMA-map memory for SEND/RECV buffers
1469 * @size: size of buffer to be allocated, in bytes
1470 * @direction: direction of data movement
1471 * @flags: GFP flags
1472 *
1473 * Returns an ERR_PTR, or a pointer to a regbuf, a buffer that
1474 * can be persistently DMA-mapped for I/O.
1475 *
1476 * xprtrdma uses a regbuf for posting an outgoing RDMA SEND, or for
1477 * receiving the payload of RDMA RECV operations. During Long Calls
1478 * or Replies they may be registered externally via ro_map.
1479 */
1480struct rpcrdma_regbuf *
1481rpcrdma_alloc_regbuf(size_t size, enum dma_data_direction direction,
1482 gfp_t flags)
1483{
1484 struct rpcrdma_regbuf *rb;
1485
1486 rb = kmalloc(sizeof(*rb) + size, flags);
1487 if (rb == NULL)
1488 return ERR_PTR(-ENOMEM);
1489
1490 rb->rg_device = NULL;
1491 rb->rg_direction = direction;
1492 rb->rg_iov.length = size;
1493
1494 return rb;
1495}
1496
1497/**
1498 * __rpcrdma_map_regbuf - DMA-map a regbuf
1499 * @ia: controlling rpcrdma_ia
1500 * @rb: regbuf to be mapped
1501 */
1502bool
1503__rpcrdma_dma_map_regbuf(struct rpcrdma_ia *ia, struct rpcrdma_regbuf *rb)
1504{
1505 struct ib_device *device = ia->ri_device;
1506
1507 if (rb->rg_direction == DMA_NONE)
1508 return false;
1509
1510 rb->rg_iov.addr = ib_dma_map_single(device,
1511 (void *)rb->rg_base,
1512 rdmab_length(rb),
1513 rb->rg_direction);
1514 if (ib_dma_mapping_error(device, rdmab_addr(rb)))
1515 return false;
1516
1517 rb->rg_device = device;
1518 rb->rg_iov.lkey = ia->ri_pd->local_dma_lkey;
1519 return true;
1520}
1521
1522static void
1523rpcrdma_dma_unmap_regbuf(struct rpcrdma_regbuf *rb)
1524{
1525 if (!rb)
1526 return;
1527
1528 if (!rpcrdma_regbuf_is_mapped(rb))
1529 return;
1530
1531 ib_dma_unmap_single(rb->rg_device, rdmab_addr(rb),
1532 rdmab_length(rb), rb->rg_direction);
1533 rb->rg_device = NULL;
1534}
1535
1536/**
1537 * rpcrdma_free_regbuf - deregister and free registered buffer
1538 * @rb: regbuf to be deregistered and freed
1539 */
1540void
1541rpcrdma_free_regbuf(struct rpcrdma_regbuf *rb)
1542{
1543 rpcrdma_dma_unmap_regbuf(rb);
1544 kfree(rb);
1545}
1546
1547/*
1548 * Prepost any receive buffer, then post send.
1549 *
1550 * Receive buffer is donated to hardware, reclaimed upon recv completion.
1551 */
1552int
1553rpcrdma_ep_post(struct rpcrdma_ia *ia,
1554 struct rpcrdma_ep *ep,
1555 struct rpcrdma_req *req)
1556{
1557 struct ib_send_wr *send_wr = &req->rl_sendctx->sc_wr;
1558 int rc;
1559
1560 if (req->rl_reply) {
1561 rc = rpcrdma_ep_post_recv(ia, req->rl_reply);
1562 if (rc)
1563 return rc;
1564 req->rl_reply = NULL;
1565 }
1566
1567 if (!ep->rep_send_count ||
1568 test_bit(RPCRDMA_REQ_F_TX_RESOURCES, &req->rl_flags)) {
1569 send_wr->send_flags |= IB_SEND_SIGNALED;
1570 ep->rep_send_count = ep->rep_send_batch;
1571 } else {
1572 send_wr->send_flags &= ~IB_SEND_SIGNALED;
1573 --ep->rep_send_count;
1574 }
1575
1576 rc = ia->ri_ops->ro_send(ia, req);
1577 trace_xprtrdma_post_send(req, rc);
1578 if (rc)
1579 return -ENOTCONN;
1580 return 0;
1581}
1582
1583int
1584rpcrdma_ep_post_recv(struct rpcrdma_ia *ia,
1585 struct rpcrdma_rep *rep)
1586{
1587 struct ib_recv_wr *recv_wr_fail;
1588 int rc;
1589
1590 if (!rpcrdma_dma_map_regbuf(ia, rep->rr_rdmabuf))
1591 goto out_map;
1592 rc = ib_post_recv(ia->ri_id->qp, &rep->rr_recv_wr, &recv_wr_fail);
1593 trace_xprtrdma_post_recv(rep, rc);
1594 if (rc)
1595 return -ENOTCONN;
1596 return 0;
1597
1598out_map:
1599 pr_err("rpcrdma: failed to DMA map the Receive buffer\n");
1600 return -EIO;
1601}
1602
1603/**
1604 * rpcrdma_ep_post_extra_recv - Post buffers for incoming backchannel requests
1605 * @r_xprt: transport associated with these backchannel resources
1606 * @count: minimum number of incoming requests expected
1607 *
1608 * Returns zero if all requested buffers were posted, or a negative errno.
1609 */
1610int
1611rpcrdma_ep_post_extra_recv(struct rpcrdma_xprt *r_xprt, unsigned int count)
1612{
1613 struct rpcrdma_buffer *buffers = &r_xprt->rx_buf;
1614 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
1615 struct rpcrdma_rep *rep;
1616 int rc;
1617
1618 while (count--) {
1619 spin_lock(&buffers->rb_lock);
1620 if (list_empty(&buffers->rb_recv_bufs))
1621 goto out_reqbuf;
1622 rep = rpcrdma_buffer_get_rep_locked(buffers);
1623 spin_unlock(&buffers->rb_lock);
1624
1625 rc = rpcrdma_ep_post_recv(ia, rep);
1626 if (rc)
1627 goto out_rc;
1628 }
1629
1630 return 0;
1631
1632out_reqbuf:
1633 spin_unlock(&buffers->rb_lock);
1634 trace_xprtrdma_noreps(r_xprt);
1635 return -ENOMEM;
1636
1637out_rc:
1638 rpcrdma_recv_buffer_put(rep);
1639 return rc;
1640}
1/*
2 * Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
3 *
4 * This software is available to you under a choice of one of two
5 * licenses. You may choose to be licensed under the terms of the GNU
6 * General Public License (GPL) Version 2, available from the file
7 * COPYING in the main directory of this source tree, or the BSD-type
8 * license below:
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 *
14 * Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 *
17 * Redistributions in binary form must reproduce the above
18 * copyright notice, this list of conditions and the following
19 * disclaimer in the documentation and/or other materials provided
20 * with the distribution.
21 *
22 * Neither the name of the Network Appliance, Inc. nor the names of
23 * its contributors may be used to endorse or promote products
24 * derived from this software without specific prior written
25 * permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
30 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
31 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
32 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
33 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
37 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
38 */
39
40/*
41 * verbs.c
42 *
43 * Encapsulates the major functions managing:
44 * o adapters
45 * o endpoints
46 * o connections
47 * o buffer memory
48 */
49
50#include <linux/interrupt.h>
51#include <linux/slab.h>
52#include <linux/prefetch.h>
53#include <linux/sunrpc/addr.h>
54#include <asm/bitops.h>
55#include <linux/module.h> /* try_module_get()/module_put() */
56
57#include "xprt_rdma.h"
58
59/*
60 * Globals/Macros
61 */
62
63#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
64# define RPCDBG_FACILITY RPCDBG_TRANS
65#endif
66
67/*
68 * internal functions
69 */
70
71static struct workqueue_struct *rpcrdma_receive_wq;
72
73int
74rpcrdma_alloc_wq(void)
75{
76 struct workqueue_struct *recv_wq;
77
78 recv_wq = alloc_workqueue("xprtrdma_receive",
79 WQ_MEM_RECLAIM | WQ_UNBOUND | WQ_HIGHPRI,
80 0);
81 if (!recv_wq)
82 return -ENOMEM;
83
84 rpcrdma_receive_wq = recv_wq;
85 return 0;
86}
87
88void
89rpcrdma_destroy_wq(void)
90{
91 struct workqueue_struct *wq;
92
93 if (rpcrdma_receive_wq) {
94 wq = rpcrdma_receive_wq;
95 rpcrdma_receive_wq = NULL;
96 destroy_workqueue(wq);
97 }
98}
99
100static void
101rpcrdma_qp_async_error_upcall(struct ib_event *event, void *context)
102{
103 struct rpcrdma_ep *ep = context;
104
105 pr_err("RPC: %s: %s on device %s ep %p\n",
106 __func__, ib_event_msg(event->event),
107 event->device->name, context);
108 if (ep->rep_connected == 1) {
109 ep->rep_connected = -EIO;
110 rpcrdma_conn_func(ep);
111 wake_up_all(&ep->rep_connect_wait);
112 }
113}
114
115/**
116 * rpcrdma_wc_send - Invoked by RDMA provider for each polled Send WC
117 * @cq: completion queue (ignored)
118 * @wc: completed WR
119 *
120 */
121static void
122rpcrdma_wc_send(struct ib_cq *cq, struct ib_wc *wc)
123{
124 /* WARNING: Only wr_cqe and status are reliable at this point */
125 if (wc->status != IB_WC_SUCCESS && wc->status != IB_WC_WR_FLUSH_ERR)
126 pr_err("rpcrdma: Send: %s (%u/0x%x)\n",
127 ib_wc_status_msg(wc->status),
128 wc->status, wc->vendor_err);
129}
130
131static void
132rpcrdma_receive_worker(struct work_struct *work)
133{
134 struct rpcrdma_rep *rep =
135 container_of(work, struct rpcrdma_rep, rr_work);
136
137 rpcrdma_reply_handler(rep);
138}
139
140/* Perform basic sanity checking to avoid using garbage
141 * to update the credit grant value.
142 */
143static void
144rpcrdma_update_granted_credits(struct rpcrdma_rep *rep)
145{
146 struct rpcrdma_msg *rmsgp = rdmab_to_msg(rep->rr_rdmabuf);
147 struct rpcrdma_buffer *buffer = &rep->rr_rxprt->rx_buf;
148 u32 credits;
149
150 if (rep->rr_len < RPCRDMA_HDRLEN_ERR)
151 return;
152
153 credits = be32_to_cpu(rmsgp->rm_credit);
154 if (credits == 0)
155 credits = 1; /* don't deadlock */
156 else if (credits > buffer->rb_max_requests)
157 credits = buffer->rb_max_requests;
158
159 atomic_set(&buffer->rb_credits, credits);
160}
161
162/**
163 * rpcrdma_receive_wc - Invoked by RDMA provider for each polled Receive WC
164 * @cq: completion queue (ignored)
165 * @wc: completed WR
166 *
167 */
168static void
169rpcrdma_receive_wc(struct ib_cq *cq, struct ib_wc *wc)
170{
171 struct ib_cqe *cqe = wc->wr_cqe;
172 struct rpcrdma_rep *rep = container_of(cqe, struct rpcrdma_rep,
173 rr_cqe);
174
175 /* WARNING: Only wr_id and status are reliable at this point */
176 if (wc->status != IB_WC_SUCCESS)
177 goto out_fail;
178
179 /* status == SUCCESS means all fields in wc are trustworthy */
180 if (wc->opcode != IB_WC_RECV)
181 return;
182
183 dprintk("RPC: %s: rep %p opcode 'recv', length %u: success\n",
184 __func__, rep, wc->byte_len);
185
186 rep->rr_len = wc->byte_len;
187 ib_dma_sync_single_for_cpu(rep->rr_device,
188 rdmab_addr(rep->rr_rdmabuf),
189 rep->rr_len, DMA_FROM_DEVICE);
190
191 rpcrdma_update_granted_credits(rep);
192
193out_schedule:
194 queue_work(rpcrdma_receive_wq, &rep->rr_work);
195 return;
196
197out_fail:
198 if (wc->status != IB_WC_WR_FLUSH_ERR)
199 pr_err("rpcrdma: Recv: %s (%u/0x%x)\n",
200 ib_wc_status_msg(wc->status),
201 wc->status, wc->vendor_err);
202 rep->rr_len = RPCRDMA_BAD_LEN;
203 goto out_schedule;
204}
205
206static void
207rpcrdma_flush_cqs(struct rpcrdma_ep *ep)
208{
209 struct ib_wc wc;
210
211 while (ib_poll_cq(ep->rep_attr.recv_cq, 1, &wc) > 0)
212 rpcrdma_receive_wc(NULL, &wc);
213}
214
215static int
216rpcrdma_conn_upcall(struct rdma_cm_id *id, struct rdma_cm_event *event)
217{
218 struct rpcrdma_xprt *xprt = id->context;
219 struct rpcrdma_ia *ia = &xprt->rx_ia;
220 struct rpcrdma_ep *ep = &xprt->rx_ep;
221#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
222 struct sockaddr *sap = (struct sockaddr *)&ep->rep_remote_addr;
223#endif
224 struct ib_qp_attr *attr = &ia->ri_qp_attr;
225 struct ib_qp_init_attr *iattr = &ia->ri_qp_init_attr;
226 int connstate = 0;
227
228 switch (event->event) {
229 case RDMA_CM_EVENT_ADDR_RESOLVED:
230 case RDMA_CM_EVENT_ROUTE_RESOLVED:
231 ia->ri_async_rc = 0;
232 complete(&ia->ri_done);
233 break;
234 case RDMA_CM_EVENT_ADDR_ERROR:
235 ia->ri_async_rc = -EHOSTUNREACH;
236 dprintk("RPC: %s: CM address resolution error, ep 0x%p\n",
237 __func__, ep);
238 complete(&ia->ri_done);
239 break;
240 case RDMA_CM_EVENT_ROUTE_ERROR:
241 ia->ri_async_rc = -ENETUNREACH;
242 dprintk("RPC: %s: CM route resolution error, ep 0x%p\n",
243 __func__, ep);
244 complete(&ia->ri_done);
245 break;
246 case RDMA_CM_EVENT_ESTABLISHED:
247 connstate = 1;
248 ib_query_qp(ia->ri_id->qp, attr,
249 IB_QP_MAX_QP_RD_ATOMIC | IB_QP_MAX_DEST_RD_ATOMIC,
250 iattr);
251 dprintk("RPC: %s: %d responder resources"
252 " (%d initiator)\n",
253 __func__, attr->max_dest_rd_atomic,
254 attr->max_rd_atomic);
255 goto connected;
256 case RDMA_CM_EVENT_CONNECT_ERROR:
257 connstate = -ENOTCONN;
258 goto connected;
259 case RDMA_CM_EVENT_UNREACHABLE:
260 connstate = -ENETDOWN;
261 goto connected;
262 case RDMA_CM_EVENT_REJECTED:
263 connstate = -ECONNREFUSED;
264 goto connected;
265 case RDMA_CM_EVENT_DISCONNECTED:
266 connstate = -ECONNABORTED;
267 goto connected;
268 case RDMA_CM_EVENT_DEVICE_REMOVAL:
269 connstate = -ENODEV;
270connected:
271 dprintk("RPC: %s: %sconnected\n",
272 __func__, connstate > 0 ? "" : "dis");
273 atomic_set(&xprt->rx_buf.rb_credits, 1);
274 ep->rep_connected = connstate;
275 rpcrdma_conn_func(ep);
276 wake_up_all(&ep->rep_connect_wait);
277 /*FALLTHROUGH*/
278 default:
279 dprintk("RPC: %s: %pIS:%u (ep 0x%p): %s\n",
280 __func__, sap, rpc_get_port(sap), ep,
281 rdma_event_msg(event->event));
282 break;
283 }
284
285#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
286 if (connstate == 1) {
287 int ird = attr->max_dest_rd_atomic;
288 int tird = ep->rep_remote_cma.responder_resources;
289
290 pr_info("rpcrdma: connection to %pIS:%u on %s, memreg '%s', %d credits, %d responders%s\n",
291 sap, rpc_get_port(sap),
292 ia->ri_device->name,
293 ia->ri_ops->ro_displayname,
294 xprt->rx_buf.rb_max_requests,
295 ird, ird < 4 && ird < tird / 2 ? " (low!)" : "");
296 } else if (connstate < 0) {
297 pr_info("rpcrdma: connection to %pIS:%u closed (%d)\n",
298 sap, rpc_get_port(sap), connstate);
299 }
300#endif
301
302 return 0;
303}
304
305static void rpcrdma_destroy_id(struct rdma_cm_id *id)
306{
307 if (id) {
308 module_put(id->device->owner);
309 rdma_destroy_id(id);
310 }
311}
312
313static struct rdma_cm_id *
314rpcrdma_create_id(struct rpcrdma_xprt *xprt,
315 struct rpcrdma_ia *ia, struct sockaddr *addr)
316{
317 struct rdma_cm_id *id;
318 int rc;
319
320 init_completion(&ia->ri_done);
321
322 id = rdma_create_id(&init_net, rpcrdma_conn_upcall, xprt, RDMA_PS_TCP,
323 IB_QPT_RC);
324 if (IS_ERR(id)) {
325 rc = PTR_ERR(id);
326 dprintk("RPC: %s: rdma_create_id() failed %i\n",
327 __func__, rc);
328 return id;
329 }
330
331 ia->ri_async_rc = -ETIMEDOUT;
332 rc = rdma_resolve_addr(id, NULL, addr, RDMA_RESOLVE_TIMEOUT);
333 if (rc) {
334 dprintk("RPC: %s: rdma_resolve_addr() failed %i\n",
335 __func__, rc);
336 goto out;
337 }
338 wait_for_completion_interruptible_timeout(&ia->ri_done,
339 msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT) + 1);
340
341 /* FIXME:
342 * Until xprtrdma supports DEVICE_REMOVAL, the provider must
343 * be pinned while there are active NFS/RDMA mounts to prevent
344 * hangs and crashes at umount time.
345 */
346 if (!ia->ri_async_rc && !try_module_get(id->device->owner)) {
347 dprintk("RPC: %s: Failed to get device module\n",
348 __func__);
349 ia->ri_async_rc = -ENODEV;
350 }
351 rc = ia->ri_async_rc;
352 if (rc)
353 goto out;
354
355 ia->ri_async_rc = -ETIMEDOUT;
356 rc = rdma_resolve_route(id, RDMA_RESOLVE_TIMEOUT);
357 if (rc) {
358 dprintk("RPC: %s: rdma_resolve_route() failed %i\n",
359 __func__, rc);
360 goto put;
361 }
362 wait_for_completion_interruptible_timeout(&ia->ri_done,
363 msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT) + 1);
364 rc = ia->ri_async_rc;
365 if (rc)
366 goto put;
367
368 return id;
369put:
370 module_put(id->device->owner);
371out:
372 rdma_destroy_id(id);
373 return ERR_PTR(rc);
374}
375
376/*
377 * Drain any cq, prior to teardown.
378 */
379static void
380rpcrdma_clean_cq(struct ib_cq *cq)
381{
382 struct ib_wc wc;
383 int count = 0;
384
385 while (1 == ib_poll_cq(cq, 1, &wc))
386 ++count;
387
388 if (count)
389 dprintk("RPC: %s: flushed %d events (last 0x%x)\n",
390 __func__, count, wc.opcode);
391}
392
393/*
394 * Exported functions.
395 */
396
397/*
398 * Open and initialize an Interface Adapter.
399 * o initializes fields of struct rpcrdma_ia, including
400 * interface and provider attributes and protection zone.
401 */
402int
403rpcrdma_ia_open(struct rpcrdma_xprt *xprt, struct sockaddr *addr, int memreg)
404{
405 struct rpcrdma_ia *ia = &xprt->rx_ia;
406 int rc;
407
408 ia->ri_dma_mr = NULL;
409
410 ia->ri_id = rpcrdma_create_id(xprt, ia, addr);
411 if (IS_ERR(ia->ri_id)) {
412 rc = PTR_ERR(ia->ri_id);
413 goto out1;
414 }
415 ia->ri_device = ia->ri_id->device;
416
417 ia->ri_pd = ib_alloc_pd(ia->ri_device);
418 if (IS_ERR(ia->ri_pd)) {
419 rc = PTR_ERR(ia->ri_pd);
420 dprintk("RPC: %s: ib_alloc_pd() failed %i\n",
421 __func__, rc);
422 goto out2;
423 }
424
425 if (memreg == RPCRDMA_FRMR) {
426 if (!(ia->ri_device->attrs.device_cap_flags &
427 IB_DEVICE_MEM_MGT_EXTENSIONS) ||
428 (ia->ri_device->attrs.max_fast_reg_page_list_len == 0)) {
429 dprintk("RPC: %s: FRMR registration "
430 "not supported by HCA\n", __func__);
431 memreg = RPCRDMA_MTHCAFMR;
432 }
433 }
434 if (memreg == RPCRDMA_MTHCAFMR) {
435 if (!ia->ri_device->alloc_fmr) {
436 dprintk("RPC: %s: MTHCAFMR registration "
437 "not supported by HCA\n", __func__);
438 rc = -EINVAL;
439 goto out3;
440 }
441 }
442
443 switch (memreg) {
444 case RPCRDMA_FRMR:
445 ia->ri_ops = &rpcrdma_frwr_memreg_ops;
446 break;
447 case RPCRDMA_ALLPHYSICAL:
448 ia->ri_ops = &rpcrdma_physical_memreg_ops;
449 break;
450 case RPCRDMA_MTHCAFMR:
451 ia->ri_ops = &rpcrdma_fmr_memreg_ops;
452 break;
453 default:
454 printk(KERN_ERR "RPC: Unsupported memory "
455 "registration mode: %d\n", memreg);
456 rc = -ENOMEM;
457 goto out3;
458 }
459 dprintk("RPC: %s: memory registration strategy is '%s'\n",
460 __func__, ia->ri_ops->ro_displayname);
461
462 rwlock_init(&ia->ri_qplock);
463 return 0;
464
465out3:
466 ib_dealloc_pd(ia->ri_pd);
467 ia->ri_pd = NULL;
468out2:
469 rpcrdma_destroy_id(ia->ri_id);
470 ia->ri_id = NULL;
471out1:
472 return rc;
473}
474
475/*
476 * Clean up/close an IA.
477 * o if event handles and PD have been initialized, free them.
478 * o close the IA
479 */
480void
481rpcrdma_ia_close(struct rpcrdma_ia *ia)
482{
483 dprintk("RPC: %s: entering\n", __func__);
484 if (ia->ri_id != NULL && !IS_ERR(ia->ri_id)) {
485 if (ia->ri_id->qp)
486 rdma_destroy_qp(ia->ri_id);
487 rpcrdma_destroy_id(ia->ri_id);
488 ia->ri_id = NULL;
489 }
490
491 /* If the pd is still busy, xprtrdma missed freeing a resource */
492 if (ia->ri_pd && !IS_ERR(ia->ri_pd))
493 ib_dealloc_pd(ia->ri_pd);
494}
495
496/*
497 * Create unconnected endpoint.
498 */
499int
500rpcrdma_ep_create(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia,
501 struct rpcrdma_create_data_internal *cdata)
502{
503 struct ib_cq *sendcq, *recvcq;
504 unsigned int max_qp_wr;
505 int rc;
506
507 if (ia->ri_device->attrs.max_sge < RPCRDMA_MAX_IOVS) {
508 dprintk("RPC: %s: insufficient sge's available\n",
509 __func__);
510 return -ENOMEM;
511 }
512
513 if (ia->ri_device->attrs.max_qp_wr <= RPCRDMA_BACKWARD_WRS) {
514 dprintk("RPC: %s: insufficient wqe's available\n",
515 __func__);
516 return -ENOMEM;
517 }
518 max_qp_wr = ia->ri_device->attrs.max_qp_wr - RPCRDMA_BACKWARD_WRS;
519
520 /* check provider's send/recv wr limits */
521 if (cdata->max_requests > max_qp_wr)
522 cdata->max_requests = max_qp_wr;
523
524 ep->rep_attr.event_handler = rpcrdma_qp_async_error_upcall;
525 ep->rep_attr.qp_context = ep;
526 ep->rep_attr.srq = NULL;
527 ep->rep_attr.cap.max_send_wr = cdata->max_requests;
528 ep->rep_attr.cap.max_send_wr += RPCRDMA_BACKWARD_WRS;
529 rc = ia->ri_ops->ro_open(ia, ep, cdata);
530 if (rc)
531 return rc;
532 ep->rep_attr.cap.max_recv_wr = cdata->max_requests;
533 ep->rep_attr.cap.max_recv_wr += RPCRDMA_BACKWARD_WRS;
534 ep->rep_attr.cap.max_send_sge = RPCRDMA_MAX_IOVS;
535 ep->rep_attr.cap.max_recv_sge = 1;
536 ep->rep_attr.cap.max_inline_data = 0;
537 ep->rep_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
538 ep->rep_attr.qp_type = IB_QPT_RC;
539 ep->rep_attr.port_num = ~0;
540
541 dprintk("RPC: %s: requested max: dtos: send %d recv %d; "
542 "iovs: send %d recv %d\n",
543 __func__,
544 ep->rep_attr.cap.max_send_wr,
545 ep->rep_attr.cap.max_recv_wr,
546 ep->rep_attr.cap.max_send_sge,
547 ep->rep_attr.cap.max_recv_sge);
548
549 /* set trigger for requesting send completion */
550 ep->rep_cqinit = ep->rep_attr.cap.max_send_wr/2 - 1;
551 if (ep->rep_cqinit <= 2)
552 ep->rep_cqinit = 0; /* always signal? */
553 INIT_CQCOUNT(ep);
554 init_waitqueue_head(&ep->rep_connect_wait);
555 INIT_DELAYED_WORK(&ep->rep_connect_worker, rpcrdma_connect_worker);
556
557 sendcq = ib_alloc_cq(ia->ri_device, NULL,
558 ep->rep_attr.cap.max_send_wr + 1,
559 0, IB_POLL_SOFTIRQ);
560 if (IS_ERR(sendcq)) {
561 rc = PTR_ERR(sendcq);
562 dprintk("RPC: %s: failed to create send CQ: %i\n",
563 __func__, rc);
564 goto out1;
565 }
566
567 recvcq = ib_alloc_cq(ia->ri_device, NULL,
568 ep->rep_attr.cap.max_recv_wr + 1,
569 0, IB_POLL_SOFTIRQ);
570 if (IS_ERR(recvcq)) {
571 rc = PTR_ERR(recvcq);
572 dprintk("RPC: %s: failed to create recv CQ: %i\n",
573 __func__, rc);
574 goto out2;
575 }
576
577 ep->rep_attr.send_cq = sendcq;
578 ep->rep_attr.recv_cq = recvcq;
579
580 /* Initialize cma parameters */
581
582 /* RPC/RDMA does not use private data */
583 ep->rep_remote_cma.private_data = NULL;
584 ep->rep_remote_cma.private_data_len = 0;
585
586 /* Client offers RDMA Read but does not initiate */
587 ep->rep_remote_cma.initiator_depth = 0;
588 if (ia->ri_device->attrs.max_qp_rd_atom > 32) /* arbitrary but <= 255 */
589 ep->rep_remote_cma.responder_resources = 32;
590 else
591 ep->rep_remote_cma.responder_resources =
592 ia->ri_device->attrs.max_qp_rd_atom;
593
594 ep->rep_remote_cma.retry_count = 7;
595 ep->rep_remote_cma.flow_control = 0;
596 ep->rep_remote_cma.rnr_retry_count = 0;
597
598 return 0;
599
600out2:
601 ib_free_cq(sendcq);
602out1:
603 if (ia->ri_dma_mr)
604 ib_dereg_mr(ia->ri_dma_mr);
605 return rc;
606}
607
608/*
609 * rpcrdma_ep_destroy
610 *
611 * Disconnect and destroy endpoint. After this, the only
612 * valid operations on the ep are to free it (if dynamically
613 * allocated) or re-create it.
614 */
615void
616rpcrdma_ep_destroy(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
617{
618 int rc;
619
620 dprintk("RPC: %s: entering, connected is %d\n",
621 __func__, ep->rep_connected);
622
623 cancel_delayed_work_sync(&ep->rep_connect_worker);
624
625 if (ia->ri_id->qp)
626 rpcrdma_ep_disconnect(ep, ia);
627
628 rpcrdma_clean_cq(ep->rep_attr.recv_cq);
629 rpcrdma_clean_cq(ep->rep_attr.send_cq);
630
631 if (ia->ri_id->qp) {
632 rdma_destroy_qp(ia->ri_id);
633 ia->ri_id->qp = NULL;
634 }
635
636 ib_free_cq(ep->rep_attr.recv_cq);
637 ib_free_cq(ep->rep_attr.send_cq);
638
639 if (ia->ri_dma_mr) {
640 rc = ib_dereg_mr(ia->ri_dma_mr);
641 dprintk("RPC: %s: ib_dereg_mr returned %i\n",
642 __func__, rc);
643 }
644}
645
646/*
647 * Connect unconnected endpoint.
648 */
649int
650rpcrdma_ep_connect(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
651{
652 struct rdma_cm_id *id, *old;
653 int rc = 0;
654 int retry_count = 0;
655
656 if (ep->rep_connected != 0) {
657 struct rpcrdma_xprt *xprt;
658retry:
659 dprintk("RPC: %s: reconnecting...\n", __func__);
660
661 rpcrdma_ep_disconnect(ep, ia);
662 rpcrdma_flush_cqs(ep);
663
664 xprt = container_of(ia, struct rpcrdma_xprt, rx_ia);
665 id = rpcrdma_create_id(xprt, ia,
666 (struct sockaddr *)&xprt->rx_data.addr);
667 if (IS_ERR(id)) {
668 rc = -EHOSTUNREACH;
669 goto out;
670 }
671 /* TEMP TEMP TEMP - fail if new device:
672 * Deregister/remarshal *all* requests!
673 * Close and recreate adapter, pd, etc!
674 * Re-determine all attributes still sane!
675 * More stuff I haven't thought of!
676 * Rrrgh!
677 */
678 if (ia->ri_device != id->device) {
679 printk("RPC: %s: can't reconnect on "
680 "different device!\n", __func__);
681 rpcrdma_destroy_id(id);
682 rc = -ENETUNREACH;
683 goto out;
684 }
685 /* END TEMP */
686 rc = rdma_create_qp(id, ia->ri_pd, &ep->rep_attr);
687 if (rc) {
688 dprintk("RPC: %s: rdma_create_qp failed %i\n",
689 __func__, rc);
690 rpcrdma_destroy_id(id);
691 rc = -ENETUNREACH;
692 goto out;
693 }
694
695 write_lock(&ia->ri_qplock);
696 old = ia->ri_id;
697 ia->ri_id = id;
698 write_unlock(&ia->ri_qplock);
699
700 rdma_destroy_qp(old);
701 rpcrdma_destroy_id(old);
702 } else {
703 dprintk("RPC: %s: connecting...\n", __func__);
704 rc = rdma_create_qp(ia->ri_id, ia->ri_pd, &ep->rep_attr);
705 if (rc) {
706 dprintk("RPC: %s: rdma_create_qp failed %i\n",
707 __func__, rc);
708 /* do not update ep->rep_connected */
709 return -ENETUNREACH;
710 }
711 }
712
713 ep->rep_connected = 0;
714
715 rc = rdma_connect(ia->ri_id, &ep->rep_remote_cma);
716 if (rc) {
717 dprintk("RPC: %s: rdma_connect() failed with %i\n",
718 __func__, rc);
719 goto out;
720 }
721
722 wait_event_interruptible(ep->rep_connect_wait, ep->rep_connected != 0);
723
724 /*
725 * Check state. A non-peer reject indicates no listener
726 * (ECONNREFUSED), which may be a transient state. All
727 * others indicate a transport condition which has already
728 * undergone a best-effort.
729 */
730 if (ep->rep_connected == -ECONNREFUSED &&
731 ++retry_count <= RDMA_CONNECT_RETRY_MAX) {
732 dprintk("RPC: %s: non-peer_reject, retry\n", __func__);
733 goto retry;
734 }
735 if (ep->rep_connected <= 0) {
736 /* Sometimes, the only way to reliably connect to remote
737 * CMs is to use same nonzero values for ORD and IRD. */
738 if (retry_count++ <= RDMA_CONNECT_RETRY_MAX + 1 &&
739 (ep->rep_remote_cma.responder_resources == 0 ||
740 ep->rep_remote_cma.initiator_depth !=
741 ep->rep_remote_cma.responder_resources)) {
742 if (ep->rep_remote_cma.responder_resources == 0)
743 ep->rep_remote_cma.responder_resources = 1;
744 ep->rep_remote_cma.initiator_depth =
745 ep->rep_remote_cma.responder_resources;
746 goto retry;
747 }
748 rc = ep->rep_connected;
749 } else {
750 struct rpcrdma_xprt *r_xprt;
751 unsigned int extras;
752
753 dprintk("RPC: %s: connected\n", __func__);
754
755 r_xprt = container_of(ia, struct rpcrdma_xprt, rx_ia);
756 extras = r_xprt->rx_buf.rb_bc_srv_max_requests;
757
758 if (extras) {
759 rc = rpcrdma_ep_post_extra_recv(r_xprt, extras);
760 if (rc) {
761 pr_warn("%s: rpcrdma_ep_post_extra_recv: %i\n",
762 __func__, rc);
763 rc = 0;
764 }
765 }
766 }
767
768out:
769 if (rc)
770 ep->rep_connected = rc;
771 return rc;
772}
773
774/*
775 * rpcrdma_ep_disconnect
776 *
777 * This is separate from destroy to facilitate the ability
778 * to reconnect without recreating the endpoint.
779 *
780 * This call is not reentrant, and must not be made in parallel
781 * on the same endpoint.
782 */
783void
784rpcrdma_ep_disconnect(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
785{
786 int rc;
787
788 rpcrdma_flush_cqs(ep);
789 rc = rdma_disconnect(ia->ri_id);
790 if (!rc) {
791 /* returns without wait if not connected */
792 wait_event_interruptible(ep->rep_connect_wait,
793 ep->rep_connected != 1);
794 dprintk("RPC: %s: after wait, %sconnected\n", __func__,
795 (ep->rep_connected == 1) ? "still " : "dis");
796 } else {
797 dprintk("RPC: %s: rdma_disconnect %i\n", __func__, rc);
798 ep->rep_connected = rc;
799 }
800}
801
802struct rpcrdma_req *
803rpcrdma_create_req(struct rpcrdma_xprt *r_xprt)
804{
805 struct rpcrdma_buffer *buffer = &r_xprt->rx_buf;
806 struct rpcrdma_req *req;
807
808 req = kzalloc(sizeof(*req), GFP_KERNEL);
809 if (req == NULL)
810 return ERR_PTR(-ENOMEM);
811
812 INIT_LIST_HEAD(&req->rl_free);
813 spin_lock(&buffer->rb_reqslock);
814 list_add(&req->rl_all, &buffer->rb_allreqs);
815 spin_unlock(&buffer->rb_reqslock);
816 req->rl_cqe.done = rpcrdma_wc_send;
817 req->rl_buffer = &r_xprt->rx_buf;
818 return req;
819}
820
821struct rpcrdma_rep *
822rpcrdma_create_rep(struct rpcrdma_xprt *r_xprt)
823{
824 struct rpcrdma_create_data_internal *cdata = &r_xprt->rx_data;
825 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
826 struct rpcrdma_rep *rep;
827 int rc;
828
829 rc = -ENOMEM;
830 rep = kzalloc(sizeof(*rep), GFP_KERNEL);
831 if (rep == NULL)
832 goto out;
833
834 rep->rr_rdmabuf = rpcrdma_alloc_regbuf(ia, cdata->inline_rsize,
835 GFP_KERNEL);
836 if (IS_ERR(rep->rr_rdmabuf)) {
837 rc = PTR_ERR(rep->rr_rdmabuf);
838 goto out_free;
839 }
840
841 rep->rr_device = ia->ri_device;
842 rep->rr_cqe.done = rpcrdma_receive_wc;
843 rep->rr_rxprt = r_xprt;
844 INIT_WORK(&rep->rr_work, rpcrdma_receive_worker);
845 return rep;
846
847out_free:
848 kfree(rep);
849out:
850 return ERR_PTR(rc);
851}
852
853int
854rpcrdma_buffer_create(struct rpcrdma_xprt *r_xprt)
855{
856 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
857 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
858 int i, rc;
859
860 buf->rb_max_requests = r_xprt->rx_data.max_requests;
861 buf->rb_bc_srv_max_requests = 0;
862 spin_lock_init(&buf->rb_lock);
863 atomic_set(&buf->rb_credits, 1);
864
865 rc = ia->ri_ops->ro_init(r_xprt);
866 if (rc)
867 goto out;
868
869 INIT_LIST_HEAD(&buf->rb_send_bufs);
870 INIT_LIST_HEAD(&buf->rb_allreqs);
871 spin_lock_init(&buf->rb_reqslock);
872 for (i = 0; i < buf->rb_max_requests; i++) {
873 struct rpcrdma_req *req;
874
875 req = rpcrdma_create_req(r_xprt);
876 if (IS_ERR(req)) {
877 dprintk("RPC: %s: request buffer %d alloc"
878 " failed\n", __func__, i);
879 rc = PTR_ERR(req);
880 goto out;
881 }
882 req->rl_backchannel = false;
883 list_add(&req->rl_free, &buf->rb_send_bufs);
884 }
885
886 INIT_LIST_HEAD(&buf->rb_recv_bufs);
887 for (i = 0; i < buf->rb_max_requests + 2; i++) {
888 struct rpcrdma_rep *rep;
889
890 rep = rpcrdma_create_rep(r_xprt);
891 if (IS_ERR(rep)) {
892 dprintk("RPC: %s: reply buffer %d alloc failed\n",
893 __func__, i);
894 rc = PTR_ERR(rep);
895 goto out;
896 }
897 list_add(&rep->rr_list, &buf->rb_recv_bufs);
898 }
899
900 return 0;
901out:
902 rpcrdma_buffer_destroy(buf);
903 return rc;
904}
905
906static struct rpcrdma_req *
907rpcrdma_buffer_get_req_locked(struct rpcrdma_buffer *buf)
908{
909 struct rpcrdma_req *req;
910
911 req = list_first_entry(&buf->rb_send_bufs,
912 struct rpcrdma_req, rl_free);
913 list_del(&req->rl_free);
914 return req;
915}
916
917static struct rpcrdma_rep *
918rpcrdma_buffer_get_rep_locked(struct rpcrdma_buffer *buf)
919{
920 struct rpcrdma_rep *rep;
921
922 rep = list_first_entry(&buf->rb_recv_bufs,
923 struct rpcrdma_rep, rr_list);
924 list_del(&rep->rr_list);
925 return rep;
926}
927
928static void
929rpcrdma_destroy_rep(struct rpcrdma_ia *ia, struct rpcrdma_rep *rep)
930{
931 rpcrdma_free_regbuf(ia, rep->rr_rdmabuf);
932 kfree(rep);
933}
934
935void
936rpcrdma_destroy_req(struct rpcrdma_ia *ia, struct rpcrdma_req *req)
937{
938 rpcrdma_free_regbuf(ia, req->rl_sendbuf);
939 rpcrdma_free_regbuf(ia, req->rl_rdmabuf);
940 kfree(req);
941}
942
943void
944rpcrdma_buffer_destroy(struct rpcrdma_buffer *buf)
945{
946 struct rpcrdma_ia *ia = rdmab_to_ia(buf);
947
948 while (!list_empty(&buf->rb_recv_bufs)) {
949 struct rpcrdma_rep *rep;
950
951 rep = rpcrdma_buffer_get_rep_locked(buf);
952 rpcrdma_destroy_rep(ia, rep);
953 }
954
955 spin_lock(&buf->rb_reqslock);
956 while (!list_empty(&buf->rb_allreqs)) {
957 struct rpcrdma_req *req;
958
959 req = list_first_entry(&buf->rb_allreqs,
960 struct rpcrdma_req, rl_all);
961 list_del(&req->rl_all);
962
963 spin_unlock(&buf->rb_reqslock);
964 rpcrdma_destroy_req(ia, req);
965 spin_lock(&buf->rb_reqslock);
966 }
967 spin_unlock(&buf->rb_reqslock);
968
969 ia->ri_ops->ro_destroy(buf);
970}
971
972struct rpcrdma_mw *
973rpcrdma_get_mw(struct rpcrdma_xprt *r_xprt)
974{
975 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
976 struct rpcrdma_mw *mw = NULL;
977
978 spin_lock(&buf->rb_mwlock);
979 if (!list_empty(&buf->rb_mws)) {
980 mw = list_first_entry(&buf->rb_mws,
981 struct rpcrdma_mw, mw_list);
982 list_del_init(&mw->mw_list);
983 }
984 spin_unlock(&buf->rb_mwlock);
985
986 if (!mw)
987 pr_err("RPC: %s: no MWs available\n", __func__);
988 return mw;
989}
990
991void
992rpcrdma_put_mw(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mw *mw)
993{
994 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
995
996 spin_lock(&buf->rb_mwlock);
997 list_add_tail(&mw->mw_list, &buf->rb_mws);
998 spin_unlock(&buf->rb_mwlock);
999}
1000
1001/*
1002 * Get a set of request/reply buffers.
1003 *
1004 * Reply buffer (if available) is attached to send buffer upon return.
1005 */
1006struct rpcrdma_req *
1007rpcrdma_buffer_get(struct rpcrdma_buffer *buffers)
1008{
1009 struct rpcrdma_req *req;
1010
1011 spin_lock(&buffers->rb_lock);
1012 if (list_empty(&buffers->rb_send_bufs))
1013 goto out_reqbuf;
1014 req = rpcrdma_buffer_get_req_locked(buffers);
1015 if (list_empty(&buffers->rb_recv_bufs))
1016 goto out_repbuf;
1017 req->rl_reply = rpcrdma_buffer_get_rep_locked(buffers);
1018 spin_unlock(&buffers->rb_lock);
1019 return req;
1020
1021out_reqbuf:
1022 spin_unlock(&buffers->rb_lock);
1023 pr_warn("RPC: %s: out of request buffers\n", __func__);
1024 return NULL;
1025out_repbuf:
1026 spin_unlock(&buffers->rb_lock);
1027 pr_warn("RPC: %s: out of reply buffers\n", __func__);
1028 req->rl_reply = NULL;
1029 return req;
1030}
1031
1032/*
1033 * Put request/reply buffers back into pool.
1034 * Pre-decrement counter/array index.
1035 */
1036void
1037rpcrdma_buffer_put(struct rpcrdma_req *req)
1038{
1039 struct rpcrdma_buffer *buffers = req->rl_buffer;
1040 struct rpcrdma_rep *rep = req->rl_reply;
1041
1042 req->rl_niovs = 0;
1043 req->rl_reply = NULL;
1044
1045 spin_lock(&buffers->rb_lock);
1046 list_add_tail(&req->rl_free, &buffers->rb_send_bufs);
1047 if (rep)
1048 list_add_tail(&rep->rr_list, &buffers->rb_recv_bufs);
1049 spin_unlock(&buffers->rb_lock);
1050}
1051
1052/*
1053 * Recover reply buffers from pool.
1054 * This happens when recovering from disconnect.
1055 */
1056void
1057rpcrdma_recv_buffer_get(struct rpcrdma_req *req)
1058{
1059 struct rpcrdma_buffer *buffers = req->rl_buffer;
1060
1061 spin_lock(&buffers->rb_lock);
1062 if (!list_empty(&buffers->rb_recv_bufs))
1063 req->rl_reply = rpcrdma_buffer_get_rep_locked(buffers);
1064 spin_unlock(&buffers->rb_lock);
1065}
1066
1067/*
1068 * Put reply buffers back into pool when not attached to
1069 * request. This happens in error conditions.
1070 */
1071void
1072rpcrdma_recv_buffer_put(struct rpcrdma_rep *rep)
1073{
1074 struct rpcrdma_buffer *buffers = &rep->rr_rxprt->rx_buf;
1075
1076 spin_lock(&buffers->rb_lock);
1077 list_add_tail(&rep->rr_list, &buffers->rb_recv_bufs);
1078 spin_unlock(&buffers->rb_lock);
1079}
1080
1081/*
1082 * Wrappers for internal-use kmalloc memory registration, used by buffer code.
1083 */
1084
1085void
1086rpcrdma_mapping_error(struct rpcrdma_mr_seg *seg)
1087{
1088 dprintk("RPC: map_one: offset %p iova %llx len %zu\n",
1089 seg->mr_offset,
1090 (unsigned long long)seg->mr_dma, seg->mr_dmalen);
1091}
1092
1093/**
1094 * rpcrdma_alloc_regbuf - kmalloc and register memory for SEND/RECV buffers
1095 * @ia: controlling rpcrdma_ia
1096 * @size: size of buffer to be allocated, in bytes
1097 * @flags: GFP flags
1098 *
1099 * Returns pointer to private header of an area of internally
1100 * registered memory, or an ERR_PTR. The registered buffer follows
1101 * the end of the private header.
1102 *
1103 * xprtrdma uses a regbuf for posting an outgoing RDMA SEND, or for
1104 * receiving the payload of RDMA RECV operations. regbufs are not
1105 * used for RDMA READ/WRITE operations, thus are registered only for
1106 * LOCAL access.
1107 */
1108struct rpcrdma_regbuf *
1109rpcrdma_alloc_regbuf(struct rpcrdma_ia *ia, size_t size, gfp_t flags)
1110{
1111 struct rpcrdma_regbuf *rb;
1112 struct ib_sge *iov;
1113
1114 rb = kmalloc(sizeof(*rb) + size, flags);
1115 if (rb == NULL)
1116 goto out;
1117
1118 iov = &rb->rg_iov;
1119 iov->addr = ib_dma_map_single(ia->ri_device,
1120 (void *)rb->rg_base, size,
1121 DMA_BIDIRECTIONAL);
1122 if (ib_dma_mapping_error(ia->ri_device, iov->addr))
1123 goto out_free;
1124
1125 iov->length = size;
1126 iov->lkey = ia->ri_pd->local_dma_lkey;
1127 rb->rg_size = size;
1128 rb->rg_owner = NULL;
1129 return rb;
1130
1131out_free:
1132 kfree(rb);
1133out:
1134 return ERR_PTR(-ENOMEM);
1135}
1136
1137/**
1138 * rpcrdma_free_regbuf - deregister and free registered buffer
1139 * @ia: controlling rpcrdma_ia
1140 * @rb: regbuf to be deregistered and freed
1141 */
1142void
1143rpcrdma_free_regbuf(struct rpcrdma_ia *ia, struct rpcrdma_regbuf *rb)
1144{
1145 struct ib_sge *iov;
1146
1147 if (!rb)
1148 return;
1149
1150 iov = &rb->rg_iov;
1151 ib_dma_unmap_single(ia->ri_device,
1152 iov->addr, iov->length, DMA_BIDIRECTIONAL);
1153 kfree(rb);
1154}
1155
1156/*
1157 * Prepost any receive buffer, then post send.
1158 *
1159 * Receive buffer is donated to hardware, reclaimed upon recv completion.
1160 */
1161int
1162rpcrdma_ep_post(struct rpcrdma_ia *ia,
1163 struct rpcrdma_ep *ep,
1164 struct rpcrdma_req *req)
1165{
1166 struct ib_device *device = ia->ri_device;
1167 struct ib_send_wr send_wr, *send_wr_fail;
1168 struct rpcrdma_rep *rep = req->rl_reply;
1169 struct ib_sge *iov = req->rl_send_iov;
1170 int i, rc;
1171
1172 if (rep) {
1173 rc = rpcrdma_ep_post_recv(ia, ep, rep);
1174 if (rc)
1175 goto out;
1176 req->rl_reply = NULL;
1177 }
1178
1179 send_wr.next = NULL;
1180 send_wr.wr_cqe = &req->rl_cqe;
1181 send_wr.sg_list = iov;
1182 send_wr.num_sge = req->rl_niovs;
1183 send_wr.opcode = IB_WR_SEND;
1184
1185 for (i = 0; i < send_wr.num_sge; i++)
1186 ib_dma_sync_single_for_device(device, iov[i].addr,
1187 iov[i].length, DMA_TO_DEVICE);
1188 dprintk("RPC: %s: posting %d s/g entries\n",
1189 __func__, send_wr.num_sge);
1190
1191 if (DECR_CQCOUNT(ep) > 0)
1192 send_wr.send_flags = 0;
1193 else { /* Provider must take a send completion every now and then */
1194 INIT_CQCOUNT(ep);
1195 send_wr.send_flags = IB_SEND_SIGNALED;
1196 }
1197
1198 rc = ib_post_send(ia->ri_id->qp, &send_wr, &send_wr_fail);
1199 if (rc)
1200 dprintk("RPC: %s: ib_post_send returned %i\n", __func__,
1201 rc);
1202out:
1203 return rc;
1204}
1205
1206/*
1207 * (Re)post a receive buffer.
1208 */
1209int
1210rpcrdma_ep_post_recv(struct rpcrdma_ia *ia,
1211 struct rpcrdma_ep *ep,
1212 struct rpcrdma_rep *rep)
1213{
1214 struct ib_recv_wr recv_wr, *recv_wr_fail;
1215 int rc;
1216
1217 recv_wr.next = NULL;
1218 recv_wr.wr_cqe = &rep->rr_cqe;
1219 recv_wr.sg_list = &rep->rr_rdmabuf->rg_iov;
1220 recv_wr.num_sge = 1;
1221
1222 ib_dma_sync_single_for_cpu(ia->ri_device,
1223 rdmab_addr(rep->rr_rdmabuf),
1224 rdmab_length(rep->rr_rdmabuf),
1225 DMA_BIDIRECTIONAL);
1226
1227 rc = ib_post_recv(ia->ri_id->qp, &recv_wr, &recv_wr_fail);
1228
1229 if (rc)
1230 dprintk("RPC: %s: ib_post_recv returned %i\n", __func__,
1231 rc);
1232 return rc;
1233}
1234
1235/**
1236 * rpcrdma_ep_post_extra_recv - Post buffers for incoming backchannel requests
1237 * @r_xprt: transport associated with these backchannel resources
1238 * @min_reqs: minimum number of incoming requests expected
1239 *
1240 * Returns zero if all requested buffers were posted, or a negative errno.
1241 */
1242int
1243rpcrdma_ep_post_extra_recv(struct rpcrdma_xprt *r_xprt, unsigned int count)
1244{
1245 struct rpcrdma_buffer *buffers = &r_xprt->rx_buf;
1246 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
1247 struct rpcrdma_ep *ep = &r_xprt->rx_ep;
1248 struct rpcrdma_rep *rep;
1249 int rc;
1250
1251 while (count--) {
1252 spin_lock(&buffers->rb_lock);
1253 if (list_empty(&buffers->rb_recv_bufs))
1254 goto out_reqbuf;
1255 rep = rpcrdma_buffer_get_rep_locked(buffers);
1256 spin_unlock(&buffers->rb_lock);
1257
1258 rc = rpcrdma_ep_post_recv(ia, ep, rep);
1259 if (rc)
1260 goto out_rc;
1261 }
1262
1263 return 0;
1264
1265out_reqbuf:
1266 spin_unlock(&buffers->rb_lock);
1267 pr_warn("%s: no extra receive buffers\n", __func__);
1268 return -ENOMEM;
1269
1270out_rc:
1271 rpcrdma_recv_buffer_put(rep);
1272 return rc;
1273}
1274
1275/* How many chunk list items fit within our inline buffers?
1276 */
1277unsigned int
1278rpcrdma_max_segments(struct rpcrdma_xprt *r_xprt)
1279{
1280 struct rpcrdma_create_data_internal *cdata = &r_xprt->rx_data;
1281 int bytes, segments;
1282
1283 bytes = min_t(unsigned int, cdata->inline_wsize, cdata->inline_rsize);
1284 bytes -= RPCRDMA_HDRLEN_MIN;
1285 if (bytes < sizeof(struct rpcrdma_segment) * 2) {
1286 pr_warn("RPC: %s: inline threshold too small\n",
1287 __func__);
1288 return 0;
1289 }
1290
1291 segments = 1 << (fls(bytes / sizeof(struct rpcrdma_segment)) - 1);
1292 dprintk("RPC: %s: max chunk list size = %d segments\n",
1293 __func__, segments);
1294 return segments;
1295}