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 static 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_xprt_connect(r_xprt);
244 xprt_clear_connecting(xprt);
245 if (!rc) {
246 xprt->connect_cookie++;
247 xprt->stat.connect_count++;
248 xprt->stat.connect_time += (long)jiffies -
249 xprt->stat.connect_start;
250 xprt_set_connected(xprt);
251 rc = -EAGAIN;
252 } else {
253 /* Force a call to xprt_rdma_close to clean up */
254 spin_lock(&xprt->transport_lock);
255 set_bit(XPRT_CLOSE_WAIT, &xprt->state);
256 spin_unlock(&xprt->transport_lock);
257 }
258 xprt_wake_pending_tasks(xprt, rc);
259 }
260
261 /**
262 * xprt_rdma_inject_disconnect - inject a connection fault
263 * @xprt: transport context
264 *
265 * If @xprt is connected, disconnect it to simulate spurious connection
266 * loss.
267 */
268 static void
xprt_rdma_inject_disconnect(struct rpc_xprt * xprt)269 xprt_rdma_inject_disconnect(struct rpc_xprt *xprt)
270 {
271 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
272
273 trace_xprtrdma_op_inject_dsc(r_xprt);
274 rdma_disconnect(r_xprt->rx_ep->re_id);
275 }
276
277 /**
278 * xprt_rdma_destroy - Full tear down of transport
279 * @xprt: doomed transport context
280 *
281 * Caller guarantees there will be no more calls to us with
282 * this @xprt.
283 */
284 static void
xprt_rdma_destroy(struct rpc_xprt * xprt)285 xprt_rdma_destroy(struct rpc_xprt *xprt)
286 {
287 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
288
289 cancel_delayed_work_sync(&r_xprt->rx_connect_worker);
290
291 rpcrdma_xprt_disconnect(r_xprt);
292 rpcrdma_buffer_destroy(&r_xprt->rx_buf);
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 if (!try_module_get(THIS_MODULE))
323 return ERR_PTR(-EIO);
324
325 xprt = xprt_alloc(args->net, sizeof(struct rpcrdma_xprt), 0,
326 xprt_rdma_slot_table_entries);
327 if (!xprt) {
328 module_put(THIS_MODULE);
329 return ERR_PTR(-ENOMEM);
330 }
331
332 xprt->timeout = &xprt_rdma_default_timeout;
333 xprt->connect_timeout = xprt->timeout->to_initval;
334 xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
335 xprt->bind_timeout = RPCRDMA_BIND_TO;
336 xprt->reestablish_timeout = RPCRDMA_INIT_REEST_TO;
337 xprt->idle_timeout = RPCRDMA_IDLE_DISC_TO;
338
339 xprt->resvport = 0; /* privileged port not needed */
340 xprt->ops = &xprt_rdma_procs;
341
342 /*
343 * Set up RDMA-specific connect data.
344 */
345 sap = args->dstaddr;
346
347 /* Ensure xprt->addr holds valid server TCP (not RDMA)
348 * address, for any side protocols which peek at it */
349 xprt->prot = IPPROTO_TCP;
350 xprt->addrlen = args->addrlen;
351 memcpy(&xprt->addr, sap, xprt->addrlen);
352
353 if (rpc_get_port(sap))
354 xprt_set_bound(xprt);
355 xprt_rdma_format_addresses(xprt, sap);
356
357 new_xprt = rpcx_to_rdmax(xprt);
358 rc = rpcrdma_buffer_create(new_xprt);
359 if (rc) {
360 xprt_rdma_free_addresses(xprt);
361 xprt_free(xprt);
362 module_put(THIS_MODULE);
363 return ERR_PTR(rc);
364 }
365
366 INIT_DELAYED_WORK(&new_xprt->rx_connect_worker,
367 xprt_rdma_connect_worker);
368
369 xprt->max_payload = RPCRDMA_MAX_DATA_SEGS << PAGE_SHIFT;
370
371 return xprt;
372 }
373
374 /**
375 * xprt_rdma_close - close a transport connection
376 * @xprt: transport context
377 *
378 * Called during autoclose or device removal.
379 *
380 * Caller holds @xprt's send lock to prevent activity on this
381 * transport while the connection is torn down.
382 */
xprt_rdma_close(struct rpc_xprt * xprt)383 void xprt_rdma_close(struct rpc_xprt *xprt)
384 {
385 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
386
387 rpcrdma_xprt_disconnect(r_xprt);
388
389 xprt->reestablish_timeout = 0;
390 ++xprt->connect_cookie;
391 xprt_disconnect_done(xprt);
392 }
393
394 /**
395 * xprt_rdma_set_port - update server port with rpcbind result
396 * @xprt: controlling RPC transport
397 * @port: new port value
398 *
399 * Transport connect status is unchanged.
400 */
401 static void
xprt_rdma_set_port(struct rpc_xprt * xprt,u16 port)402 xprt_rdma_set_port(struct rpc_xprt *xprt, u16 port)
403 {
404 struct sockaddr *sap = (struct sockaddr *)&xprt->addr;
405 char buf[8];
406
407 rpc_set_port(sap, port);
408
409 kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
410 snprintf(buf, sizeof(buf), "%u", port);
411 xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
412
413 kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
414 snprintf(buf, sizeof(buf), "%4hx", port);
415 xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
416 }
417
418 /**
419 * xprt_rdma_timer - invoked when an RPC times out
420 * @xprt: controlling RPC transport
421 * @task: RPC task that timed out
422 *
423 * Invoked when the transport is still connected, but an RPC
424 * retransmit timeout occurs.
425 *
426 * Since RDMA connections don't have a keep-alive, forcibly
427 * disconnect and retry to connect. This drives full
428 * detection of the network path, and retransmissions of
429 * all pending RPCs.
430 */
431 static void
xprt_rdma_timer(struct rpc_xprt * xprt,struct rpc_task * task)432 xprt_rdma_timer(struct rpc_xprt *xprt, struct rpc_task *task)
433 {
434 xprt_force_disconnect(xprt);
435 }
436
437 /**
438 * xprt_rdma_set_connect_timeout - set timeouts for establishing a connection
439 * @xprt: controlling transport instance
440 * @connect_timeout: reconnect timeout after client disconnects
441 * @reconnect_timeout: reconnect timeout after server disconnects
442 *
443 */
xprt_rdma_set_connect_timeout(struct rpc_xprt * xprt,unsigned long connect_timeout,unsigned long reconnect_timeout)444 static void xprt_rdma_set_connect_timeout(struct rpc_xprt *xprt,
445 unsigned long connect_timeout,
446 unsigned long reconnect_timeout)
447 {
448 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
449
450 trace_xprtrdma_op_set_cto(r_xprt, connect_timeout, reconnect_timeout);
451
452 spin_lock(&xprt->transport_lock);
453
454 if (connect_timeout < xprt->connect_timeout) {
455 struct rpc_timeout to;
456 unsigned long initval;
457
458 to = *xprt->timeout;
459 initval = connect_timeout;
460 if (initval < RPCRDMA_INIT_REEST_TO << 1)
461 initval = RPCRDMA_INIT_REEST_TO << 1;
462 to.to_initval = initval;
463 to.to_maxval = initval;
464 r_xprt->rx_timeout = to;
465 xprt->timeout = &r_xprt->rx_timeout;
466 xprt->connect_timeout = connect_timeout;
467 }
468
469 if (reconnect_timeout < xprt->max_reconnect_timeout)
470 xprt->max_reconnect_timeout = reconnect_timeout;
471
472 spin_unlock(&xprt->transport_lock);
473 }
474
475 /**
476 * xprt_rdma_connect - schedule an attempt to reconnect
477 * @xprt: transport state
478 * @task: RPC scheduler context (unused)
479 *
480 */
481 static void
xprt_rdma_connect(struct rpc_xprt * xprt,struct rpc_task * task)482 xprt_rdma_connect(struct rpc_xprt *xprt, struct rpc_task *task)
483 {
484 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
485 struct rpcrdma_ep *ep = r_xprt->rx_ep;
486 unsigned long delay;
487
488 delay = 0;
489 if (ep && ep->re_connect_status != 0) {
490 delay = xprt_reconnect_delay(xprt);
491 xprt_reconnect_backoff(xprt, RPCRDMA_INIT_REEST_TO);
492 }
493 trace_xprtrdma_op_connect(r_xprt, delay);
494 queue_delayed_work(xprtiod_workqueue, &r_xprt->rx_connect_worker,
495 delay);
496 }
497
498 /**
499 * xprt_rdma_alloc_slot - allocate an rpc_rqst
500 * @xprt: controlling RPC transport
501 * @task: RPC task requesting a fresh rpc_rqst
502 *
503 * tk_status values:
504 * %0 if task->tk_rqstp points to a fresh rpc_rqst
505 * %-EAGAIN if no rpc_rqst is available; queued on backlog
506 */
507 static void
xprt_rdma_alloc_slot(struct rpc_xprt * xprt,struct rpc_task * task)508 xprt_rdma_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task)
509 {
510 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
511 struct rpcrdma_req *req;
512
513 req = rpcrdma_buffer_get(&r_xprt->rx_buf);
514 if (!req)
515 goto out_sleep;
516 task->tk_rqstp = &req->rl_slot;
517 task->tk_status = 0;
518 return;
519
520 out_sleep:
521 set_bit(XPRT_CONGESTED, &xprt->state);
522 rpc_sleep_on(&xprt->backlog, task, NULL);
523 task->tk_status = -EAGAIN;
524 }
525
526 /**
527 * xprt_rdma_free_slot - release an rpc_rqst
528 * @xprt: controlling RPC transport
529 * @rqst: rpc_rqst to release
530 *
531 */
532 static void
xprt_rdma_free_slot(struct rpc_xprt * xprt,struct rpc_rqst * rqst)533 xprt_rdma_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *rqst)
534 {
535 struct rpcrdma_xprt *r_xprt =
536 container_of(xprt, struct rpcrdma_xprt, rx_xprt);
537
538 memset(rqst, 0, sizeof(*rqst));
539 rpcrdma_buffer_put(&r_xprt->rx_buf, rpcr_to_rdmar(rqst));
540 if (unlikely(!rpc_wake_up_next(&xprt->backlog)))
541 clear_bit(XPRT_CONGESTED, &xprt->state);
542 }
543
rpcrdma_check_regbuf(struct rpcrdma_xprt * r_xprt,struct rpcrdma_regbuf * rb,size_t size,gfp_t flags)544 static bool rpcrdma_check_regbuf(struct rpcrdma_xprt *r_xprt,
545 struct rpcrdma_regbuf *rb, size_t size,
546 gfp_t flags)
547 {
548 if (unlikely(rdmab_length(rb) < size)) {
549 if (!rpcrdma_regbuf_realloc(rb, size, flags))
550 return false;
551 r_xprt->rx_stats.hardway_register_count += size;
552 }
553 return true;
554 }
555
556 /**
557 * xprt_rdma_allocate - allocate transport resources for an RPC
558 * @task: RPC task
559 *
560 * Return values:
561 * 0: Success; rq_buffer points to RPC buffer to use
562 * ENOMEM: Out of memory, call again later
563 * EIO: A permanent error occurred, do not retry
564 */
565 static int
xprt_rdma_allocate(struct rpc_task * task)566 xprt_rdma_allocate(struct rpc_task *task)
567 {
568 struct rpc_rqst *rqst = task->tk_rqstp;
569 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(rqst->rq_xprt);
570 struct rpcrdma_req *req = rpcr_to_rdmar(rqst);
571 gfp_t flags;
572
573 flags = RPCRDMA_DEF_GFP;
574 if (RPC_IS_SWAPPER(task))
575 flags = __GFP_MEMALLOC | GFP_NOWAIT | __GFP_NOWARN;
576
577 if (!rpcrdma_check_regbuf(r_xprt, req->rl_sendbuf, rqst->rq_callsize,
578 flags))
579 goto out_fail;
580 if (!rpcrdma_check_regbuf(r_xprt, req->rl_recvbuf, rqst->rq_rcvsize,
581 flags))
582 goto out_fail;
583
584 rqst->rq_buffer = rdmab_data(req->rl_sendbuf);
585 rqst->rq_rbuffer = rdmab_data(req->rl_recvbuf);
586 return 0;
587
588 out_fail:
589 return -ENOMEM;
590 }
591
592 /**
593 * xprt_rdma_free - release resources allocated by xprt_rdma_allocate
594 * @task: RPC task
595 *
596 * Caller guarantees rqst->rq_buffer is non-NULL.
597 */
598 static void
xprt_rdma_free(struct rpc_task * task)599 xprt_rdma_free(struct rpc_task *task)
600 {
601 struct rpc_rqst *rqst = task->tk_rqstp;
602 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(rqst->rq_xprt);
603 struct rpcrdma_req *req = rpcr_to_rdmar(rqst);
604
605 if (!list_empty(&req->rl_registered))
606 frwr_unmap_sync(r_xprt, req);
607
608 /* XXX: If the RPC is completing because of a signal and
609 * not because a reply was received, we ought to ensure
610 * that the Send completion has fired, so that memory
611 * involved with the Send is not still visible to the NIC.
612 */
613 }
614
615 /**
616 * xprt_rdma_send_request - marshal and send an RPC request
617 * @rqst: RPC message in rq_snd_buf
618 *
619 * Caller holds the transport's write lock.
620 *
621 * Returns:
622 * %0 if the RPC message has been sent
623 * %-ENOTCONN if the caller should reconnect and call again
624 * %-EAGAIN if the caller should call again
625 * %-ENOBUFS if the caller should call again after a delay
626 * %-EMSGSIZE if encoding ran out of buffer space. The request
627 * was not sent. Do not try to send this message again.
628 * %-EIO if an I/O error occurred. The request was not sent.
629 * Do not try to send this message again.
630 */
631 static int
xprt_rdma_send_request(struct rpc_rqst * rqst)632 xprt_rdma_send_request(struct rpc_rqst *rqst)
633 {
634 struct rpc_xprt *xprt = rqst->rq_xprt;
635 struct rpcrdma_req *req = rpcr_to_rdmar(rqst);
636 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
637 int rc = 0;
638
639 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
640 if (unlikely(!rqst->rq_buffer))
641 return xprt_rdma_bc_send_reply(rqst);
642 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
643
644 if (!xprt_connected(xprt))
645 return -ENOTCONN;
646
647 if (!xprt_request_get_cong(xprt, rqst))
648 return -EBADSLT;
649
650 rc = rpcrdma_marshal_req(r_xprt, rqst);
651 if (rc < 0)
652 goto failed_marshal;
653
654 /* Must suppress retransmit to maintain credits */
655 if (rqst->rq_connect_cookie == xprt->connect_cookie)
656 goto drop_connection;
657 rqst->rq_xtime = ktime_get();
658
659 if (rpcrdma_post_sends(r_xprt, req))
660 goto drop_connection;
661
662 rqst->rq_xmit_bytes_sent += rqst->rq_snd_buf.len;
663
664 /* An RPC with no reply will throw off credit accounting,
665 * so drop the connection to reset the credit grant.
666 */
667 if (!rpc_reply_expected(rqst->rq_task))
668 goto drop_connection;
669 return 0;
670
671 failed_marshal:
672 if (rc != -ENOTCONN)
673 return rc;
674 drop_connection:
675 xprt_rdma_close(xprt);
676 return -ENOTCONN;
677 }
678
xprt_rdma_print_stats(struct rpc_xprt * xprt,struct seq_file * seq)679 void xprt_rdma_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
680 {
681 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
682 long idle_time = 0;
683
684 if (xprt_connected(xprt))
685 idle_time = (long)(jiffies - xprt->last_used) / HZ;
686
687 seq_puts(seq, "\txprt:\trdma ");
688 seq_printf(seq, "%u %lu %lu %lu %ld %lu %lu %lu %llu %llu ",
689 0, /* need a local port? */
690 xprt->stat.bind_count,
691 xprt->stat.connect_count,
692 xprt->stat.connect_time / HZ,
693 idle_time,
694 xprt->stat.sends,
695 xprt->stat.recvs,
696 xprt->stat.bad_xids,
697 xprt->stat.req_u,
698 xprt->stat.bklog_u);
699 seq_printf(seq, "%lu %lu %lu %llu %llu %llu %llu %lu %lu %lu %lu ",
700 r_xprt->rx_stats.read_chunk_count,
701 r_xprt->rx_stats.write_chunk_count,
702 r_xprt->rx_stats.reply_chunk_count,
703 r_xprt->rx_stats.total_rdma_request,
704 r_xprt->rx_stats.total_rdma_reply,
705 r_xprt->rx_stats.pullup_copy_count,
706 r_xprt->rx_stats.fixup_copy_count,
707 r_xprt->rx_stats.hardway_register_count,
708 r_xprt->rx_stats.failed_marshal_count,
709 r_xprt->rx_stats.bad_reply_count,
710 r_xprt->rx_stats.nomsg_call_count);
711 seq_printf(seq, "%lu %lu %lu %lu %lu %lu\n",
712 r_xprt->rx_stats.mrs_recycled,
713 r_xprt->rx_stats.mrs_orphaned,
714 r_xprt->rx_stats.mrs_allocated,
715 r_xprt->rx_stats.local_inv_needed,
716 r_xprt->rx_stats.empty_sendctx_q,
717 r_xprt->rx_stats.reply_waits_for_send);
718 }
719
720 static int
xprt_rdma_enable_swap(struct rpc_xprt * xprt)721 xprt_rdma_enable_swap(struct rpc_xprt *xprt)
722 {
723 return 0;
724 }
725
726 static void
xprt_rdma_disable_swap(struct rpc_xprt * xprt)727 xprt_rdma_disable_swap(struct rpc_xprt *xprt)
728 {
729 }
730
731 /*
732 * Plumbing for rpc transport switch and kernel module
733 */
734
735 static const struct rpc_xprt_ops xprt_rdma_procs = {
736 .reserve_xprt = xprt_reserve_xprt_cong,
737 .release_xprt = xprt_release_xprt_cong, /* sunrpc/xprt.c */
738 .alloc_slot = xprt_rdma_alloc_slot,
739 .free_slot = xprt_rdma_free_slot,
740 .release_request = xprt_release_rqst_cong, /* ditto */
741 .wait_for_reply_request = xprt_wait_for_reply_request_def, /* ditto */
742 .timer = xprt_rdma_timer,
743 .rpcbind = rpcb_getport_async, /* sunrpc/rpcb_clnt.c */
744 .set_port = xprt_rdma_set_port,
745 .connect = xprt_rdma_connect,
746 .buf_alloc = xprt_rdma_allocate,
747 .buf_free = xprt_rdma_free,
748 .send_request = xprt_rdma_send_request,
749 .close = xprt_rdma_close,
750 .destroy = xprt_rdma_destroy,
751 .set_connect_timeout = xprt_rdma_set_connect_timeout,
752 .print_stats = xprt_rdma_print_stats,
753 .enable_swap = xprt_rdma_enable_swap,
754 .disable_swap = xprt_rdma_disable_swap,
755 .inject_disconnect = xprt_rdma_inject_disconnect,
756 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
757 .bc_setup = xprt_rdma_bc_setup,
758 .bc_maxpayload = xprt_rdma_bc_maxpayload,
759 .bc_num_slots = xprt_rdma_bc_max_slots,
760 .bc_free_rqst = xprt_rdma_bc_free_rqst,
761 .bc_destroy = xprt_rdma_bc_destroy,
762 #endif
763 };
764
765 static struct xprt_class xprt_rdma = {
766 .list = LIST_HEAD_INIT(xprt_rdma.list),
767 .name = "rdma",
768 .owner = THIS_MODULE,
769 .ident = XPRT_TRANSPORT_RDMA,
770 .setup = xprt_setup_rdma,
771 };
772
xprt_rdma_cleanup(void)773 void xprt_rdma_cleanup(void)
774 {
775 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
776 if (sunrpc_table_header) {
777 unregister_sysctl_table(sunrpc_table_header);
778 sunrpc_table_header = NULL;
779 }
780 #endif
781
782 xprt_unregister_transport(&xprt_rdma);
783 xprt_unregister_transport(&xprt_rdma_bc);
784 }
785
xprt_rdma_init(void)786 int xprt_rdma_init(void)
787 {
788 int rc;
789
790 rc = xprt_register_transport(&xprt_rdma);
791 if (rc)
792 return rc;
793
794 rc = xprt_register_transport(&xprt_rdma_bc);
795 if (rc) {
796 xprt_unregister_transport(&xprt_rdma);
797 return rc;
798 }
799
800 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
801 if (!sunrpc_table_header)
802 sunrpc_table_header = register_sysctl_table(sunrpc_table);
803 #endif
804 return 0;
805 }
806
