1 // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
2 /*
3 * Copyright (c) 2014-2017 Oracle. All rights reserved.
4 * Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
5 *
6 * This software is available to you under a choice of one of two
7 * licenses. You may choose to be licensed under the terms of the GNU
8 * General Public License (GPL) Version 2, available from the file
9 * COPYING in the main directory of this source tree, or the BSD-type
10 * license below:
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 *
16 * Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 *
19 * Redistributions in binary form must reproduce the above
20 * copyright notice, this list of conditions and the following
21 * disclaimer in the documentation and/or other materials provided
22 * with the distribution.
23 *
24 * Neither the name of the Network Appliance, Inc. nor the names of
25 * its contributors may be used to endorse or promote products
26 * derived from this software without specific prior written
27 * permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
30 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
31 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
32 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
33 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
34 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
35 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
39 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
40 */
41
42 /*
43 * transport.c
44 *
45 * This file contains the top-level implementation of an RPC RDMA
46 * transport.
47 *
48 * Naming convention: functions beginning with xprt_ are part of the
49 * transport switch. All others are RPC RDMA internal.
50 */
51
52 #include <linux/module.h>
53 #include <linux/slab.h>
54 #include <linux/seq_file.h>
55 #include <linux/smp.h>
56
57 #include <linux/sunrpc/addr.h>
58 #include <linux/sunrpc/svc_rdma.h>
59
60 #include "xprt_rdma.h"
61 #include <trace/events/rpcrdma.h>
62
63 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
64 # define RPCDBG_FACILITY RPCDBG_TRANS
65 #endif
66
67 /*
68 * tunables
69 */
70
71 unsigned int xprt_rdma_slot_table_entries = RPCRDMA_DEF_SLOT_TABLE;
72 unsigned int xprt_rdma_max_inline_read = RPCRDMA_DEF_INLINE;
73 unsigned int xprt_rdma_max_inline_write = RPCRDMA_DEF_INLINE;
74 unsigned int xprt_rdma_memreg_strategy = RPCRDMA_FRWR;
75 int xprt_rdma_pad_optimize;
76
77 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
78
79 static unsigned int min_slot_table_size = RPCRDMA_MIN_SLOT_TABLE;
80 static unsigned int max_slot_table_size = RPCRDMA_MAX_SLOT_TABLE;
81 static unsigned int min_inline_size = RPCRDMA_MIN_INLINE;
82 static unsigned int max_inline_size = RPCRDMA_MAX_INLINE;
83 static unsigned int max_padding = PAGE_SIZE;
84 static unsigned int min_memreg = RPCRDMA_BOUNCEBUFFERS;
85 static unsigned int max_memreg = RPCRDMA_LAST - 1;
86 static unsigned int dummy;
87
88 static struct ctl_table_header *sunrpc_table_header;
89
90 static struct ctl_table xr_tunables_table[] = {
91 {
92 .procname = "rdma_slot_table_entries",
93 .data = &xprt_rdma_slot_table_entries,
94 .maxlen = sizeof(unsigned int),
95 .mode = 0644,
96 .proc_handler = proc_dointvec_minmax,
97 .extra1 = &min_slot_table_size,
98 .extra2 = &max_slot_table_size
99 },
100 {
101 .procname = "rdma_max_inline_read",
102 .data = &xprt_rdma_max_inline_read,
103 .maxlen = sizeof(unsigned int),
104 .mode = 0644,
105 .proc_handler = proc_dointvec_minmax,
106 .extra1 = &min_inline_size,
107 .extra2 = &max_inline_size,
108 },
109 {
110 .procname = "rdma_max_inline_write",
111 .data = &xprt_rdma_max_inline_write,
112 .maxlen = sizeof(unsigned int),
113 .mode = 0644,
114 .proc_handler = proc_dointvec_minmax,
115 .extra1 = &min_inline_size,
116 .extra2 = &max_inline_size,
117 },
118 {
119 .procname = "rdma_inline_write_padding",
120 .data = &dummy,
121 .maxlen = sizeof(unsigned int),
122 .mode = 0644,
123 .proc_handler = proc_dointvec_minmax,
124 .extra1 = SYSCTL_ZERO,
125 .extra2 = &max_padding,
126 },
127 {
128 .procname = "rdma_memreg_strategy",
129 .data = &xprt_rdma_memreg_strategy,
130 .maxlen = sizeof(unsigned int),
131 .mode = 0644,
132 .proc_handler = proc_dointvec_minmax,
133 .extra1 = &min_memreg,
134 .extra2 = &max_memreg,
135 },
136 {
137 .procname = "rdma_pad_optimize",
138 .data = &xprt_rdma_pad_optimize,
139 .maxlen = sizeof(unsigned int),
140 .mode = 0644,
141 .proc_handler = proc_dointvec,
142 },
143 { },
144 };
145
146 static struct ctl_table sunrpc_table[] = {
147 {
148 .procname = "sunrpc",
149 .mode = 0555,
150 .child = xr_tunables_table
151 },
152 { },
153 };
154
155 #endif
156
157 static const struct rpc_xprt_ops xprt_rdma_procs;
158
159 static void
xprt_rdma_format_addresses4(struct rpc_xprt * xprt,struct sockaddr * sap)160 xprt_rdma_format_addresses4(struct rpc_xprt *xprt, struct sockaddr *sap)
161 {
162 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
163 char buf[20];
164
165 snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
166 xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
167
168 xprt->address_strings[RPC_DISPLAY_NETID] = RPCBIND_NETID_RDMA;
169 }
170
171 static void
xprt_rdma_format_addresses6(struct rpc_xprt * xprt,struct sockaddr * sap)172 xprt_rdma_format_addresses6(struct rpc_xprt *xprt, struct sockaddr *sap)
173 {
174 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
175 char buf[40];
176
177 snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
178 xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
179
180 xprt->address_strings[RPC_DISPLAY_NETID] = RPCBIND_NETID_RDMA6;
181 }
182
183 void
xprt_rdma_format_addresses(struct rpc_xprt * xprt,struct sockaddr * sap)184 xprt_rdma_format_addresses(struct rpc_xprt *xprt, struct sockaddr *sap)
185 {
186 char buf[128];
187
188 switch (sap->sa_family) {
189 case AF_INET:
190 xprt_rdma_format_addresses4(xprt, sap);
191 break;
192 case AF_INET6:
193 xprt_rdma_format_addresses6(xprt, sap);
194 break;
195 default:
196 pr_err("rpcrdma: Unrecognized address family\n");
197 return;
198 }
199
200 (void)rpc_ntop(sap, buf, sizeof(buf));
201 xprt->address_strings[RPC_DISPLAY_ADDR] = kstrdup(buf, GFP_KERNEL);
202
203 snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
204 xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
205
206 snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
207 xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
208
209 xprt->address_strings[RPC_DISPLAY_PROTO] = "rdma";
210 }
211
212 void
xprt_rdma_free_addresses(struct rpc_xprt * xprt)213 xprt_rdma_free_addresses(struct rpc_xprt *xprt)
214 {
215 unsigned int i;
216
217 for (i = 0; i < RPC_DISPLAY_MAX; i++)
218 switch (i) {
219 case RPC_DISPLAY_PROTO:
220 case RPC_DISPLAY_NETID:
221 continue;
222 default:
223 kfree(xprt->address_strings[i]);
224 }
225 }
226
227 /**
228 * xprt_rdma_connect_worker - establish connection in the background
229 * @work: worker thread context
230 *
231 * Requester holds the xprt's send lock to prevent activity on this
232 * transport while a fresh connection is being established. RPC tasks
233 * sleep on the xprt's pending queue waiting for connect to complete.
234 */
235 static void
xprt_rdma_connect_worker(struct work_struct * work)236 xprt_rdma_connect_worker(struct work_struct *work)
237 {
238 struct rpcrdma_xprt *r_xprt = container_of(work, struct rpcrdma_xprt,
239 rx_connect_worker.work);
240 struct rpc_xprt *xprt = &r_xprt->rx_xprt;
241 int rc;
242
243 rc = rpcrdma_ep_connect(&r_xprt->rx_ep, &r_xprt->rx_ia);
244 xprt_clear_connecting(xprt);
245 if (r_xprt->rx_ep.rep_connected > 0) {
246 if (!xprt_test_and_set_connected(xprt)) {
247 xprt->stat.connect_count++;
248 xprt->stat.connect_time += (long)jiffies -
249 xprt->stat.connect_start;
250 xprt_wake_pending_tasks(xprt, -EAGAIN);
251 }
252 } else {
253 if (xprt_test_and_clear_connected(xprt))
254 xprt_wake_pending_tasks(xprt, rc);
255 }
256 }
257
258 /**
259 * xprt_rdma_inject_disconnect - inject a connection fault
260 * @xprt: transport context
261 *
262 * If @xprt is connected, disconnect it to simulate spurious connection
263 * loss.
264 */
265 static void
xprt_rdma_inject_disconnect(struct rpc_xprt * xprt)266 xprt_rdma_inject_disconnect(struct rpc_xprt *xprt)
267 {
268 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
269
270 trace_xprtrdma_op_inject_dsc(r_xprt);
271 rdma_disconnect(r_xprt->rx_ia.ri_id);
272 }
273
274 /**
275 * xprt_rdma_destroy - Full tear down of transport
276 * @xprt: doomed transport context
277 *
278 * Caller guarantees there will be no more calls to us with
279 * this @xprt.
280 */
281 static void
xprt_rdma_destroy(struct rpc_xprt * xprt)282 xprt_rdma_destroy(struct rpc_xprt *xprt)
283 {
284 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
285
286 trace_xprtrdma_op_destroy(r_xprt);
287
288 cancel_delayed_work_sync(&r_xprt->rx_connect_worker);
289
290 rpcrdma_ep_destroy(r_xprt);
291 rpcrdma_buffer_destroy(&r_xprt->rx_buf);
292 rpcrdma_ia_close(&r_xprt->rx_ia);
293
294 xprt_rdma_free_addresses(xprt);
295 xprt_free(xprt);
296
297 module_put(THIS_MODULE);
298 }
299
300 /* 60 second timeout, no retries */
301 static const struct rpc_timeout xprt_rdma_default_timeout = {
302 .to_initval = 60 * HZ,
303 .to_maxval = 60 * HZ,
304 };
305
306 /**
307 * xprt_setup_rdma - Set up transport to use RDMA
308 *
309 * @args: rpc transport arguments
310 */
311 static struct rpc_xprt *
xprt_setup_rdma(struct xprt_create * args)312 xprt_setup_rdma(struct xprt_create *args)
313 {
314 struct rpc_xprt *xprt;
315 struct rpcrdma_xprt *new_xprt;
316 struct sockaddr *sap;
317 int rc;
318
319 if (args->addrlen > sizeof(xprt->addr))
320 return ERR_PTR(-EBADF);
321
322 xprt = xprt_alloc(args->net, sizeof(struct rpcrdma_xprt), 0, 0);
323 if (!xprt)
324 return ERR_PTR(-ENOMEM);
325
326 xprt->timeout = &xprt_rdma_default_timeout;
327 xprt->connect_timeout = xprt->timeout->to_initval;
328 xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
329 xprt->bind_timeout = RPCRDMA_BIND_TO;
330 xprt->reestablish_timeout = RPCRDMA_INIT_REEST_TO;
331 xprt->idle_timeout = RPCRDMA_IDLE_DISC_TO;
332
333 xprt->resvport = 0; /* privileged port not needed */
334 xprt->ops = &xprt_rdma_procs;
335
336 /*
337 * Set up RDMA-specific connect data.
338 */
339 sap = args->dstaddr;
340
341 /* Ensure xprt->addr holds valid server TCP (not RDMA)
342 * address, for any side protocols which peek at it */
343 xprt->prot = IPPROTO_TCP;
344 xprt->addrlen = args->addrlen;
345 memcpy(&xprt->addr, sap, xprt->addrlen);
346
347 if (rpc_get_port(sap))
348 xprt_set_bound(xprt);
349 xprt_rdma_format_addresses(xprt, sap);
350
351 new_xprt = rpcx_to_rdmax(xprt);
352 rc = rpcrdma_ia_open(new_xprt);
353 if (rc)
354 goto out1;
355
356 rc = rpcrdma_ep_create(new_xprt);
357 if (rc)
358 goto out2;
359
360 rc = rpcrdma_buffer_create(new_xprt);
361 if (rc)
362 goto out3;
363
364 INIT_DELAYED_WORK(&new_xprt->rx_connect_worker,
365 xprt_rdma_connect_worker);
366
367 xprt->max_payload = frwr_maxpages(new_xprt);
368 if (xprt->max_payload == 0)
369 goto out4;
370 xprt->max_payload <<= PAGE_SHIFT;
371 dprintk("RPC: %s: transport data payload maximum: %zu bytes\n",
372 __func__, xprt->max_payload);
373
374 if (!try_module_get(THIS_MODULE))
375 goto out4;
376
377 dprintk("RPC: %s: %s:%s\n", __func__,
378 xprt->address_strings[RPC_DISPLAY_ADDR],
379 xprt->address_strings[RPC_DISPLAY_PORT]);
380 trace_xprtrdma_create(new_xprt);
381 return xprt;
382
383 out4:
384 rpcrdma_buffer_destroy(&new_xprt->rx_buf);
385 rc = -ENODEV;
386 out3:
387 rpcrdma_ep_destroy(new_xprt);
388 out2:
389 rpcrdma_ia_close(&new_xprt->rx_ia);
390 out1:
391 trace_xprtrdma_op_destroy(new_xprt);
392 xprt_rdma_free_addresses(xprt);
393 xprt_free(xprt);
394 return ERR_PTR(rc);
395 }
396
397 /**
398 * xprt_rdma_close - close a transport connection
399 * @xprt: transport context
400 *
401 * Called during autoclose or device removal.
402 *
403 * Caller holds @xprt's send lock to prevent activity on this
404 * transport while the connection is torn down.
405 */
xprt_rdma_close(struct rpc_xprt * xprt)406 void xprt_rdma_close(struct rpc_xprt *xprt)
407 {
408 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
409 struct rpcrdma_ep *ep = &r_xprt->rx_ep;
410 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
411
412 might_sleep();
413
414 trace_xprtrdma_op_close(r_xprt);
415
416 /* Prevent marshaling and sending of new requests */
417 xprt_clear_connected(xprt);
418
419 if (test_and_clear_bit(RPCRDMA_IAF_REMOVING, &ia->ri_flags)) {
420 rpcrdma_ia_remove(ia);
421 goto out;
422 }
423
424 if (ep->rep_connected == -ENODEV)
425 return;
426 rpcrdma_ep_disconnect(ep, ia);
427
428 /* Prepare @xprt for the next connection by reinitializing
429 * its credit grant to one (see RFC 8166, Section 3.3.3).
430 */
431 r_xprt->rx_buf.rb_credits = 1;
432 xprt->cwnd = RPC_CWNDSHIFT;
433
434 out:
435 xprt->reestablish_timeout = 0;
436 ++xprt->connect_cookie;
437 xprt_disconnect_done(xprt);
438 }
439
440 /**
441 * xprt_rdma_set_port - update server port with rpcbind result
442 * @xprt: controlling RPC transport
443 * @port: new port value
444 *
445 * Transport connect status is unchanged.
446 */
447 static void
xprt_rdma_set_port(struct rpc_xprt * xprt,u16 port)448 xprt_rdma_set_port(struct rpc_xprt *xprt, u16 port)
449 {
450 struct sockaddr *sap = (struct sockaddr *)&xprt->addr;
451 char buf[8];
452
453 dprintk("RPC: %s: setting port for xprt %p (%s:%s) to %u\n",
454 __func__, xprt,
455 xprt->address_strings[RPC_DISPLAY_ADDR],
456 xprt->address_strings[RPC_DISPLAY_PORT],
457 port);
458
459 rpc_set_port(sap, port);
460
461 kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
462 snprintf(buf, sizeof(buf), "%u", port);
463 xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
464
465 kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
466 snprintf(buf, sizeof(buf), "%4hx", port);
467 xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
468 }
469
470 /**
471 * xprt_rdma_timer - invoked when an RPC times out
472 * @xprt: controlling RPC transport
473 * @task: RPC task that timed out
474 *
475 * Invoked when the transport is still connected, but an RPC
476 * retransmit timeout occurs.
477 *
478 * Since RDMA connections don't have a keep-alive, forcibly
479 * disconnect and retry to connect. This drives full
480 * detection of the network path, and retransmissions of
481 * all pending RPCs.
482 */
483 static void
xprt_rdma_timer(struct rpc_xprt * xprt,struct rpc_task * task)484 xprt_rdma_timer(struct rpc_xprt *xprt, struct rpc_task *task)
485 {
486 xprt_force_disconnect(xprt);
487 }
488
489 /**
490 * xprt_rdma_set_connect_timeout - set timeouts for establishing a connection
491 * @xprt: controlling transport instance
492 * @connect_timeout: reconnect timeout after client disconnects
493 * @reconnect_timeout: reconnect timeout after server disconnects
494 *
495 */
xprt_rdma_set_connect_timeout(struct rpc_xprt * xprt,unsigned long connect_timeout,unsigned long reconnect_timeout)496 static void xprt_rdma_set_connect_timeout(struct rpc_xprt *xprt,
497 unsigned long connect_timeout,
498 unsigned long reconnect_timeout)
499 {
500 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
501
502 trace_xprtrdma_op_set_cto(r_xprt, connect_timeout, reconnect_timeout);
503
504 spin_lock(&xprt->transport_lock);
505
506 if (connect_timeout < xprt->connect_timeout) {
507 struct rpc_timeout to;
508 unsigned long initval;
509
510 to = *xprt->timeout;
511 initval = connect_timeout;
512 if (initval < RPCRDMA_INIT_REEST_TO << 1)
513 initval = RPCRDMA_INIT_REEST_TO << 1;
514 to.to_initval = initval;
515 to.to_maxval = initval;
516 r_xprt->rx_timeout = to;
517 xprt->timeout = &r_xprt->rx_timeout;
518 xprt->connect_timeout = connect_timeout;
519 }
520
521 if (reconnect_timeout < xprt->max_reconnect_timeout)
522 xprt->max_reconnect_timeout = reconnect_timeout;
523
524 spin_unlock(&xprt->transport_lock);
525 }
526
527 /**
528 * xprt_rdma_connect - schedule an attempt to reconnect
529 * @xprt: transport state
530 * @task: RPC scheduler context (unused)
531 *
532 */
533 static void
xprt_rdma_connect(struct rpc_xprt * xprt,struct rpc_task * task)534 xprt_rdma_connect(struct rpc_xprt *xprt, struct rpc_task *task)
535 {
536 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
537 unsigned long delay;
538
539 trace_xprtrdma_op_connect(r_xprt);
540
541 delay = 0;
542 if (r_xprt->rx_ep.rep_connected != 0) {
543 delay = xprt_reconnect_delay(xprt);
544 xprt_reconnect_backoff(xprt, RPCRDMA_INIT_REEST_TO);
545 }
546 queue_delayed_work(xprtiod_workqueue, &r_xprt->rx_connect_worker,
547 delay);
548 }
549
550 /**
551 * xprt_rdma_alloc_slot - allocate an rpc_rqst
552 * @xprt: controlling RPC transport
553 * @task: RPC task requesting a fresh rpc_rqst
554 *
555 * tk_status values:
556 * %0 if task->tk_rqstp points to a fresh rpc_rqst
557 * %-EAGAIN if no rpc_rqst is available; queued on backlog
558 */
559 static void
xprt_rdma_alloc_slot(struct rpc_xprt * xprt,struct rpc_task * task)560 xprt_rdma_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task)
561 {
562 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
563 struct rpcrdma_req *req;
564
565 req = rpcrdma_buffer_get(&r_xprt->rx_buf);
566 if (!req)
567 goto out_sleep;
568 task->tk_rqstp = &req->rl_slot;
569 task->tk_status = 0;
570 return;
571
572 out_sleep:
573 set_bit(XPRT_CONGESTED, &xprt->state);
574 rpc_sleep_on(&xprt->backlog, task, NULL);
575 task->tk_status = -EAGAIN;
576 }
577
578 /**
579 * xprt_rdma_free_slot - release an rpc_rqst
580 * @xprt: controlling RPC transport
581 * @rqst: rpc_rqst to release
582 *
583 */
584 static void
xprt_rdma_free_slot(struct rpc_xprt * xprt,struct rpc_rqst * rqst)585 xprt_rdma_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *rqst)
586 {
587 struct rpcrdma_xprt *r_xprt =
588 container_of(xprt, struct rpcrdma_xprt, rx_xprt);
589
590 memset(rqst, 0, sizeof(*rqst));
591 rpcrdma_buffer_put(&r_xprt->rx_buf, rpcr_to_rdmar(rqst));
592 if (unlikely(!rpc_wake_up_next(&xprt->backlog)))
593 clear_bit(XPRT_CONGESTED, &xprt->state);
594 }
595
rpcrdma_check_regbuf(struct rpcrdma_xprt * r_xprt,struct rpcrdma_regbuf * rb,size_t size,gfp_t flags)596 static bool rpcrdma_check_regbuf(struct rpcrdma_xprt *r_xprt,
597 struct rpcrdma_regbuf *rb, size_t size,
598 gfp_t flags)
599 {
600 if (unlikely(rdmab_length(rb) < size)) {
601 if (!rpcrdma_regbuf_realloc(rb, size, flags))
602 return false;
603 r_xprt->rx_stats.hardway_register_count += size;
604 }
605 return true;
606 }
607
608 /**
609 * xprt_rdma_allocate - allocate transport resources for an RPC
610 * @task: RPC task
611 *
612 * Return values:
613 * 0: Success; rq_buffer points to RPC buffer to use
614 * ENOMEM: Out of memory, call again later
615 * EIO: A permanent error occurred, do not retry
616 */
617 static int
xprt_rdma_allocate(struct rpc_task * task)618 xprt_rdma_allocate(struct rpc_task *task)
619 {
620 struct rpc_rqst *rqst = task->tk_rqstp;
621 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(rqst->rq_xprt);
622 struct rpcrdma_req *req = rpcr_to_rdmar(rqst);
623 gfp_t flags;
624
625 flags = RPCRDMA_DEF_GFP;
626 if (RPC_IS_SWAPPER(task))
627 flags = __GFP_MEMALLOC | GFP_NOWAIT | __GFP_NOWARN;
628
629 if (!rpcrdma_check_regbuf(r_xprt, req->rl_sendbuf, rqst->rq_callsize,
630 flags))
631 goto out_fail;
632 if (!rpcrdma_check_regbuf(r_xprt, req->rl_recvbuf, rqst->rq_rcvsize,
633 flags))
634 goto out_fail;
635
636 rqst->rq_buffer = rdmab_data(req->rl_sendbuf);
637 rqst->rq_rbuffer = rdmab_data(req->rl_recvbuf);
638 trace_xprtrdma_op_allocate(task, req);
639 return 0;
640
641 out_fail:
642 trace_xprtrdma_op_allocate(task, NULL);
643 return -ENOMEM;
644 }
645
646 /**
647 * xprt_rdma_free - release resources allocated by xprt_rdma_allocate
648 * @task: RPC task
649 *
650 * Caller guarantees rqst->rq_buffer is non-NULL.
651 */
652 static void
xprt_rdma_free(struct rpc_task * task)653 xprt_rdma_free(struct rpc_task *task)
654 {
655 struct rpc_rqst *rqst = task->tk_rqstp;
656 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(rqst->rq_xprt);
657 struct rpcrdma_req *req = rpcr_to_rdmar(rqst);
658
659 trace_xprtrdma_op_free(task, req);
660
661 if (!list_empty(&req->rl_registered))
662 frwr_unmap_sync(r_xprt, req);
663
664 /* XXX: If the RPC is completing because of a signal and
665 * not because a reply was received, we ought to ensure
666 * that the Send completion has fired, so that memory
667 * involved with the Send is not still visible to the NIC.
668 */
669 }
670
671 /**
672 * xprt_rdma_send_request - marshal and send an RPC request
673 * @rqst: RPC message in rq_snd_buf
674 *
675 * Caller holds the transport's write lock.
676 *
677 * Returns:
678 * %0 if the RPC message has been sent
679 * %-ENOTCONN if the caller should reconnect and call again
680 * %-EAGAIN if the caller should call again
681 * %-ENOBUFS if the caller should call again after a delay
682 * %-EMSGSIZE if encoding ran out of buffer space. The request
683 * was not sent. Do not try to send this message again.
684 * %-EIO if an I/O error occurred. The request was not sent.
685 * Do not try to send this message again.
686 */
687 static int
xprt_rdma_send_request(struct rpc_rqst * rqst)688 xprt_rdma_send_request(struct rpc_rqst *rqst)
689 {
690 struct rpc_xprt *xprt = rqst->rq_xprt;
691 struct rpcrdma_req *req = rpcr_to_rdmar(rqst);
692 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
693 int rc = 0;
694
695 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
696 if (unlikely(!rqst->rq_buffer))
697 return xprt_rdma_bc_send_reply(rqst);
698 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
699
700 if (!xprt_connected(xprt))
701 return -ENOTCONN;
702
703 if (!xprt_request_get_cong(xprt, rqst))
704 return -EBADSLT;
705
706 rc = rpcrdma_marshal_req(r_xprt, rqst);
707 if (rc < 0)
708 goto failed_marshal;
709
710 /* Must suppress retransmit to maintain credits */
711 if (rqst->rq_connect_cookie == xprt->connect_cookie)
712 goto drop_connection;
713 rqst->rq_xtime = ktime_get();
714
715 if (rpcrdma_ep_post(&r_xprt->rx_ia, &r_xprt->rx_ep, req))
716 goto drop_connection;
717
718 rqst->rq_xmit_bytes_sent += rqst->rq_snd_buf.len;
719
720 /* An RPC with no reply will throw off credit accounting,
721 * so drop the connection to reset the credit grant.
722 */
723 if (!rpc_reply_expected(rqst->rq_task))
724 goto drop_connection;
725 return 0;
726
727 failed_marshal:
728 if (rc != -ENOTCONN)
729 return rc;
730 drop_connection:
731 xprt_rdma_close(xprt);
732 return -ENOTCONN;
733 }
734
xprt_rdma_print_stats(struct rpc_xprt * xprt,struct seq_file * seq)735 void xprt_rdma_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
736 {
737 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
738 long idle_time = 0;
739
740 if (xprt_connected(xprt))
741 idle_time = (long)(jiffies - xprt->last_used) / HZ;
742
743 seq_puts(seq, "\txprt:\trdma ");
744 seq_printf(seq, "%u %lu %lu %lu %ld %lu %lu %lu %llu %llu ",
745 0, /* need a local port? */
746 xprt->stat.bind_count,
747 xprt->stat.connect_count,
748 xprt->stat.connect_time / HZ,
749 idle_time,
750 xprt->stat.sends,
751 xprt->stat.recvs,
752 xprt->stat.bad_xids,
753 xprt->stat.req_u,
754 xprt->stat.bklog_u);
755 seq_printf(seq, "%lu %lu %lu %llu %llu %llu %llu %lu %lu %lu %lu ",
756 r_xprt->rx_stats.read_chunk_count,
757 r_xprt->rx_stats.write_chunk_count,
758 r_xprt->rx_stats.reply_chunk_count,
759 r_xprt->rx_stats.total_rdma_request,
760 r_xprt->rx_stats.total_rdma_reply,
761 r_xprt->rx_stats.pullup_copy_count,
762 r_xprt->rx_stats.fixup_copy_count,
763 r_xprt->rx_stats.hardway_register_count,
764 r_xprt->rx_stats.failed_marshal_count,
765 r_xprt->rx_stats.bad_reply_count,
766 r_xprt->rx_stats.nomsg_call_count);
767 seq_printf(seq, "%lu %lu %lu %lu %lu %lu\n",
768 r_xprt->rx_stats.mrs_recycled,
769 r_xprt->rx_stats.mrs_orphaned,
770 r_xprt->rx_stats.mrs_allocated,
771 r_xprt->rx_stats.local_inv_needed,
772 r_xprt->rx_stats.empty_sendctx_q,
773 r_xprt->rx_stats.reply_waits_for_send);
774 }
775
776 static int
xprt_rdma_enable_swap(struct rpc_xprt * xprt)777 xprt_rdma_enable_swap(struct rpc_xprt *xprt)
778 {
779 return 0;
780 }
781
782 static void
xprt_rdma_disable_swap(struct rpc_xprt * xprt)783 xprt_rdma_disable_swap(struct rpc_xprt *xprt)
784 {
785 }
786
787 /*
788 * Plumbing for rpc transport switch and kernel module
789 */
790
791 static const struct rpc_xprt_ops xprt_rdma_procs = {
792 .reserve_xprt = xprt_reserve_xprt_cong,
793 .release_xprt = xprt_release_xprt_cong, /* sunrpc/xprt.c */
794 .alloc_slot = xprt_rdma_alloc_slot,
795 .free_slot = xprt_rdma_free_slot,
796 .release_request = xprt_release_rqst_cong, /* ditto */
797 .wait_for_reply_request = xprt_wait_for_reply_request_def, /* ditto */
798 .timer = xprt_rdma_timer,
799 .rpcbind = rpcb_getport_async, /* sunrpc/rpcb_clnt.c */
800 .set_port = xprt_rdma_set_port,
801 .connect = xprt_rdma_connect,
802 .buf_alloc = xprt_rdma_allocate,
803 .buf_free = xprt_rdma_free,
804 .send_request = xprt_rdma_send_request,
805 .close = xprt_rdma_close,
806 .destroy = xprt_rdma_destroy,
807 .set_connect_timeout = xprt_rdma_set_connect_timeout,
808 .print_stats = xprt_rdma_print_stats,
809 .enable_swap = xprt_rdma_enable_swap,
810 .disable_swap = xprt_rdma_disable_swap,
811 .inject_disconnect = xprt_rdma_inject_disconnect,
812 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
813 .bc_setup = xprt_rdma_bc_setup,
814 .bc_maxpayload = xprt_rdma_bc_maxpayload,
815 .bc_num_slots = xprt_rdma_bc_max_slots,
816 .bc_free_rqst = xprt_rdma_bc_free_rqst,
817 .bc_destroy = xprt_rdma_bc_destroy,
818 #endif
819 };
820
821 static struct xprt_class xprt_rdma = {
822 .list = LIST_HEAD_INIT(xprt_rdma.list),
823 .name = "rdma",
824 .owner = THIS_MODULE,
825 .ident = XPRT_TRANSPORT_RDMA,
826 .setup = xprt_setup_rdma,
827 };
828
xprt_rdma_cleanup(void)829 void xprt_rdma_cleanup(void)
830 {
831 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
832 if (sunrpc_table_header) {
833 unregister_sysctl_table(sunrpc_table_header);
834 sunrpc_table_header = NULL;
835 }
836 #endif
837
838 xprt_unregister_transport(&xprt_rdma);
839 xprt_unregister_transport(&xprt_rdma_bc);
840 }
841
xprt_rdma_init(void)842 int xprt_rdma_init(void)
843 {
844 int rc;
845
846 rc = xprt_register_transport(&xprt_rdma);
847 if (rc)
848 return rc;
849
850 rc = xprt_register_transport(&xprt_rdma_bc);
851 if (rc) {
852 xprt_unregister_transport(&xprt_rdma);
853 return rc;
854 }
855
856 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
857 if (!sunrpc_table_header)
858 sunrpc_table_header = register_sysctl_table(sunrpc_table);
859 #endif
860 return 0;
861 }
862
