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1/*
2 * Copyright (c) 2015 Oracle. All rights reserved.
3 * Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
4 */
5
6/* Lightweight memory registration using Fast Registration Work
7 * Requests (FRWR). Also referred to sometimes as FRMR mode.
8 *
9 * FRWR features ordered asynchronous registration and deregistration
10 * of arbitrarily sized memory regions. This is the fastest and safest
11 * but most complex memory registration mode.
12 */
13
14/* Normal operation
15 *
16 * A Memory Region is prepared for RDMA READ or WRITE using a FAST_REG
17 * Work Request (frmr_op_map). When the RDMA operation is finished, this
18 * Memory Region is invalidated using a LOCAL_INV Work Request
19 * (frmr_op_unmap).
20 *
21 * Typically these Work Requests are not signaled, and neither are RDMA
22 * SEND Work Requests (with the exception of signaling occasionally to
23 * prevent provider work queue overflows). This greatly reduces HCA
24 * interrupt workload.
25 *
26 * As an optimization, frwr_op_unmap marks MRs INVALID before the
27 * LOCAL_INV WR is posted. If posting succeeds, the MR is placed on
28 * rb_mws immediately so that no work (like managing a linked list
29 * under a spinlock) is needed in the completion upcall.
30 *
31 * But this means that frwr_op_map() can occasionally encounter an MR
32 * that is INVALID but the LOCAL_INV WR has not completed. Work Queue
33 * ordering prevents a subsequent FAST_REG WR from executing against
34 * that MR while it is still being invalidated.
35 */
36
37/* Transport recovery
38 *
39 * ->op_map and the transport connect worker cannot run at the same
40 * time, but ->op_unmap can fire while the transport connect worker
41 * is running. Thus MR recovery is handled in ->op_map, to guarantee
42 * that recovered MRs are owned by a sending RPC, and not one where
43 * ->op_unmap could fire at the same time transport reconnect is
44 * being done.
45 *
46 * When the underlying transport disconnects, MRs are left in one of
47 * three states:
48 *
49 * INVALID: The MR was not in use before the QP entered ERROR state.
50 * (Or, the LOCAL_INV WR has not completed or flushed yet).
51 *
52 * STALE: The MR was being registered or unregistered when the QP
53 * entered ERROR state, and the pending WR was flushed.
54 *
55 * VALID: The MR was registered before the QP entered ERROR state.
56 *
57 * When frwr_op_map encounters STALE and VALID MRs, they are recovered
58 * with ib_dereg_mr and then are re-initialized. Beause MR recovery
59 * allocates fresh resources, it is deferred to a workqueue, and the
60 * recovered MRs are placed back on the rb_mws list when recovery is
61 * complete. frwr_op_map allocates another MR for the current RPC while
62 * the broken MR is reset.
63 *
64 * To ensure that frwr_op_map doesn't encounter an MR that is marked
65 * INVALID but that is about to be flushed due to a previous transport
66 * disconnect, the transport connect worker attempts to drain all
67 * pending send queue WRs before the transport is reconnected.
68 */
69
70#include "xprt_rdma.h"
71
72#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
73# define RPCDBG_FACILITY RPCDBG_TRANS
74#endif
75
76static struct workqueue_struct *frwr_recovery_wq;
77
78#define FRWR_RECOVERY_WQ_FLAGS (WQ_UNBOUND | WQ_MEM_RECLAIM)
79
80int
81frwr_alloc_recovery_wq(void)
82{
83 frwr_recovery_wq = alloc_workqueue("frwr_recovery",
84 FRWR_RECOVERY_WQ_FLAGS, 0);
85 return !frwr_recovery_wq ? -ENOMEM : 0;
86}
87
88void
89frwr_destroy_recovery_wq(void)
90{
91 struct workqueue_struct *wq;
92
93 if (!frwr_recovery_wq)
94 return;
95
96 wq = frwr_recovery_wq;
97 frwr_recovery_wq = NULL;
98 destroy_workqueue(wq);
99}
100
101/* Deferred reset of a single FRMR. Generate a fresh rkey by
102 * replacing the MR.
103 *
104 * There's no recovery if this fails. The FRMR is abandoned, but
105 * remains in rb_all. It will be cleaned up when the transport is
106 * destroyed.
107 */
108static void
109__frwr_recovery_worker(struct work_struct *work)
110{
111 struct rpcrdma_mw *r = container_of(work, struct rpcrdma_mw,
112 frmr.fr_work);
113 struct rpcrdma_xprt *r_xprt = r->frmr.fr_xprt;
114 unsigned int depth = r_xprt->rx_ia.ri_max_frmr_depth;
115 struct ib_pd *pd = r_xprt->rx_ia.ri_pd;
116
117 if (ib_dereg_mr(r->frmr.fr_mr))
118 goto out_fail;
119
120 r->frmr.fr_mr = ib_alloc_mr(pd, IB_MR_TYPE_MEM_REG, depth);
121 if (IS_ERR(r->frmr.fr_mr))
122 goto out_fail;
123
124 dprintk("RPC: %s: recovered FRMR %p\n", __func__, r);
125 r->frmr.fr_state = FRMR_IS_INVALID;
126 rpcrdma_put_mw(r_xprt, r);
127 return;
128
129out_fail:
130 pr_warn("RPC: %s: FRMR %p unrecovered\n",
131 __func__, r);
132}
133
134/* A broken MR was discovered in a context that can't sleep.
135 * Defer recovery to the recovery worker.
136 */
137static void
138__frwr_queue_recovery(struct rpcrdma_mw *r)
139{
140 INIT_WORK(&r->frmr.fr_work, __frwr_recovery_worker);
141 queue_work(frwr_recovery_wq, &r->frmr.fr_work);
142}
143
144static int
145__frwr_init(struct rpcrdma_mw *r, struct ib_pd *pd, struct ib_device *device,
146 unsigned int depth)
147{
148 struct rpcrdma_frmr *f = &r->frmr;
149 int rc;
150
151 f->fr_mr = ib_alloc_mr(pd, IB_MR_TYPE_MEM_REG, depth);
152 if (IS_ERR(f->fr_mr))
153 goto out_mr_err;
154
155 f->sg = kcalloc(depth, sizeof(*f->sg), GFP_KERNEL);
156 if (!f->sg)
157 goto out_list_err;
158
159 sg_init_table(f->sg, depth);
160
161 init_completion(&f->fr_linv_done);
162
163 return 0;
164
165out_mr_err:
166 rc = PTR_ERR(f->fr_mr);
167 dprintk("RPC: %s: ib_alloc_mr status %i\n",
168 __func__, rc);
169 return rc;
170
171out_list_err:
172 rc = -ENOMEM;
173 dprintk("RPC: %s: sg allocation failure\n",
174 __func__);
175 ib_dereg_mr(f->fr_mr);
176 return rc;
177}
178
179static void
180__frwr_release(struct rpcrdma_mw *r)
181{
182 int rc;
183
184 rc = ib_dereg_mr(r->frmr.fr_mr);
185 if (rc)
186 dprintk("RPC: %s: ib_dereg_mr status %i\n",
187 __func__, rc);
188 kfree(r->frmr.sg);
189}
190
191static int
192frwr_op_open(struct rpcrdma_ia *ia, struct rpcrdma_ep *ep,
193 struct rpcrdma_create_data_internal *cdata)
194{
195 int depth, delta;
196
197 ia->ri_max_frmr_depth =
198 min_t(unsigned int, RPCRDMA_MAX_DATA_SEGS,
199 ia->ri_device->attrs.max_fast_reg_page_list_len);
200 dprintk("RPC: %s: device's max FR page list len = %u\n",
201 __func__, ia->ri_max_frmr_depth);
202
203 /* Add room for frmr register and invalidate WRs.
204 * 1. FRMR reg WR for head
205 * 2. FRMR invalidate WR for head
206 * 3. N FRMR reg WRs for pagelist
207 * 4. N FRMR invalidate WRs for pagelist
208 * 5. FRMR reg WR for tail
209 * 6. FRMR invalidate WR for tail
210 * 7. The RDMA_SEND WR
211 */
212 depth = 7;
213
214 /* Calculate N if the device max FRMR depth is smaller than
215 * RPCRDMA_MAX_DATA_SEGS.
216 */
217 if (ia->ri_max_frmr_depth < RPCRDMA_MAX_DATA_SEGS) {
218 delta = RPCRDMA_MAX_DATA_SEGS - ia->ri_max_frmr_depth;
219 do {
220 depth += 2; /* FRMR reg + invalidate */
221 delta -= ia->ri_max_frmr_depth;
222 } while (delta > 0);
223 }
224
225 ep->rep_attr.cap.max_send_wr *= depth;
226 if (ep->rep_attr.cap.max_send_wr > ia->ri_device->attrs.max_qp_wr) {
227 cdata->max_requests = ia->ri_device->attrs.max_qp_wr / depth;
228 if (!cdata->max_requests)
229 return -EINVAL;
230 ep->rep_attr.cap.max_send_wr = cdata->max_requests *
231 depth;
232 }
233
234 return 0;
235}
236
237/* FRWR mode conveys a list of pages per chunk segment. The
238 * maximum length of that list is the FRWR page list depth.
239 */
240static size_t
241frwr_op_maxpages(struct rpcrdma_xprt *r_xprt)
242{
243 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
244
245 return min_t(unsigned int, RPCRDMA_MAX_DATA_SEGS,
246 rpcrdma_max_segments(r_xprt) * ia->ri_max_frmr_depth);
247}
248
249static void
250__frwr_sendcompletion_flush(struct ib_wc *wc, struct rpcrdma_frmr *frmr,
251 const char *wr)
252{
253 frmr->fr_state = FRMR_IS_STALE;
254 if (wc->status != IB_WC_WR_FLUSH_ERR)
255 pr_err("rpcrdma: %s: %s (%u/0x%x)\n",
256 wr, ib_wc_status_msg(wc->status),
257 wc->status, wc->vendor_err);
258}
259
260/**
261 * frwr_wc_fastreg - Invoked by RDMA provider for each polled FastReg WC
262 * @cq: completion queue (ignored)
263 * @wc: completed WR
264 *
265 */
266static void
267frwr_wc_fastreg(struct ib_cq *cq, struct ib_wc *wc)
268{
269 struct rpcrdma_frmr *frmr;
270 struct ib_cqe *cqe;
271
272 /* WARNING: Only wr_cqe and status are reliable at this point */
273 if (wc->status != IB_WC_SUCCESS) {
274 cqe = wc->wr_cqe;
275 frmr = container_of(cqe, struct rpcrdma_frmr, fr_cqe);
276 __frwr_sendcompletion_flush(wc, frmr, "fastreg");
277 }
278}
279
280/**
281 * frwr_wc_localinv - Invoked by RDMA provider for each polled LocalInv WC
282 * @cq: completion queue (ignored)
283 * @wc: completed WR
284 *
285 */
286static void
287frwr_wc_localinv(struct ib_cq *cq, struct ib_wc *wc)
288{
289 struct rpcrdma_frmr *frmr;
290 struct ib_cqe *cqe;
291
292 /* WARNING: Only wr_cqe and status are reliable at this point */
293 if (wc->status != IB_WC_SUCCESS) {
294 cqe = wc->wr_cqe;
295 frmr = container_of(cqe, struct rpcrdma_frmr, fr_cqe);
296 __frwr_sendcompletion_flush(wc, frmr, "localinv");
297 }
298}
299
300/**
301 * frwr_wc_localinv - Invoked by RDMA provider for each polled LocalInv WC
302 * @cq: completion queue (ignored)
303 * @wc: completed WR
304 *
305 * Awaken anyone waiting for an MR to finish being fenced.
306 */
307static void
308frwr_wc_localinv_wake(struct ib_cq *cq, struct ib_wc *wc)
309{
310 struct rpcrdma_frmr *frmr;
311 struct ib_cqe *cqe;
312
313 /* WARNING: Only wr_cqe and status are reliable at this point */
314 cqe = wc->wr_cqe;
315 frmr = container_of(cqe, struct rpcrdma_frmr, fr_cqe);
316 if (wc->status != IB_WC_SUCCESS)
317 __frwr_sendcompletion_flush(wc, frmr, "localinv");
318 complete_all(&frmr->fr_linv_done);
319}
320
321static int
322frwr_op_init(struct rpcrdma_xprt *r_xprt)
323{
324 struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
325 struct ib_device *device = r_xprt->rx_ia.ri_device;
326 unsigned int depth = r_xprt->rx_ia.ri_max_frmr_depth;
327 struct ib_pd *pd = r_xprt->rx_ia.ri_pd;
328 int i;
329
330 spin_lock_init(&buf->rb_mwlock);
331 INIT_LIST_HEAD(&buf->rb_mws);
332 INIT_LIST_HEAD(&buf->rb_all);
333
334 i = max_t(int, RPCRDMA_MAX_DATA_SEGS / depth, 1);
335 i += 2; /* head + tail */
336 i *= buf->rb_max_requests; /* one set for each RPC slot */
337 dprintk("RPC: %s: initalizing %d FRMRs\n", __func__, i);
338
339 while (i--) {
340 struct rpcrdma_mw *r;
341 int rc;
342
343 r = kzalloc(sizeof(*r), GFP_KERNEL);
344 if (!r)
345 return -ENOMEM;
346
347 rc = __frwr_init(r, pd, device, depth);
348 if (rc) {
349 kfree(r);
350 return rc;
351 }
352
353 list_add(&r->mw_list, &buf->rb_mws);
354 list_add(&r->mw_all, &buf->rb_all);
355 r->frmr.fr_xprt = r_xprt;
356 }
357
358 return 0;
359}
360
361/* Post a FAST_REG Work Request to register a memory region
362 * for remote access via RDMA READ or RDMA WRITE.
363 */
364static int
365frwr_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg,
366 int nsegs, bool writing)
367{
368 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
369 struct ib_device *device = ia->ri_device;
370 enum dma_data_direction direction = rpcrdma_data_dir(writing);
371 struct rpcrdma_mr_seg *seg1 = seg;
372 struct rpcrdma_mw *mw;
373 struct rpcrdma_frmr *frmr;
374 struct ib_mr *mr;
375 struct ib_reg_wr *reg_wr;
376 struct ib_send_wr *bad_wr;
377 int rc, i, n, dma_nents;
378 u8 key;
379
380 mw = seg1->rl_mw;
381 seg1->rl_mw = NULL;
382 do {
383 if (mw)
384 __frwr_queue_recovery(mw);
385 mw = rpcrdma_get_mw(r_xprt);
386 if (!mw)
387 return -ENOMEM;
388 } while (mw->frmr.fr_state != FRMR_IS_INVALID);
389 frmr = &mw->frmr;
390 frmr->fr_state = FRMR_IS_VALID;
391 mr = frmr->fr_mr;
392 reg_wr = &frmr->fr_regwr;
393
394 if (nsegs > ia->ri_max_frmr_depth)
395 nsegs = ia->ri_max_frmr_depth;
396
397 for (i = 0; i < nsegs;) {
398 if (seg->mr_page)
399 sg_set_page(&frmr->sg[i],
400 seg->mr_page,
401 seg->mr_len,
402 offset_in_page(seg->mr_offset));
403 else
404 sg_set_buf(&frmr->sg[i], seg->mr_offset,
405 seg->mr_len);
406
407 ++seg;
408 ++i;
409
410 /* Check for holes */
411 if ((i < nsegs && offset_in_page(seg->mr_offset)) ||
412 offset_in_page((seg-1)->mr_offset + (seg-1)->mr_len))
413 break;
414 }
415 frmr->sg_nents = i;
416
417 dma_nents = ib_dma_map_sg(device, frmr->sg, frmr->sg_nents, direction);
418 if (!dma_nents) {
419 pr_err("RPC: %s: failed to dma map sg %p sg_nents %u\n",
420 __func__, frmr->sg, frmr->sg_nents);
421 return -ENOMEM;
422 }
423
424 n = ib_map_mr_sg(mr, frmr->sg, frmr->sg_nents, PAGE_SIZE);
425 if (unlikely(n != frmr->sg_nents)) {
426 pr_err("RPC: %s: failed to map mr %p (%u/%u)\n",
427 __func__, frmr->fr_mr, n, frmr->sg_nents);
428 rc = n < 0 ? n : -EINVAL;
429 goto out_senderr;
430 }
431
432 dprintk("RPC: %s: Using frmr %p to map %u segments (%u bytes)\n",
433 __func__, mw, frmr->sg_nents, mr->length);
434
435 key = (u8)(mr->rkey & 0x000000FF);
436 ib_update_fast_reg_key(mr, ++key);
437
438 reg_wr->wr.next = NULL;
439 reg_wr->wr.opcode = IB_WR_REG_MR;
440 frmr->fr_cqe.done = frwr_wc_fastreg;
441 reg_wr->wr.wr_cqe = &frmr->fr_cqe;
442 reg_wr->wr.num_sge = 0;
443 reg_wr->wr.send_flags = 0;
444 reg_wr->mr = mr;
445 reg_wr->key = mr->rkey;
446 reg_wr->access = writing ?
447 IB_ACCESS_REMOTE_WRITE | IB_ACCESS_LOCAL_WRITE :
448 IB_ACCESS_REMOTE_READ;
449
450 DECR_CQCOUNT(&r_xprt->rx_ep);
451 rc = ib_post_send(ia->ri_id->qp, ®_wr->wr, &bad_wr);
452 if (rc)
453 goto out_senderr;
454
455 seg1->mr_dir = direction;
456 seg1->rl_mw = mw;
457 seg1->mr_rkey = mr->rkey;
458 seg1->mr_base = mr->iova;
459 seg1->mr_nsegs = frmr->sg_nents;
460 seg1->mr_len = mr->length;
461
462 return frmr->sg_nents;
463
464out_senderr:
465 dprintk("RPC: %s: ib_post_send status %i\n", __func__, rc);
466 ib_dma_unmap_sg(device, frmr->sg, dma_nents, direction);
467 __frwr_queue_recovery(mw);
468 return rc;
469}
470
471static struct ib_send_wr *
472__frwr_prepare_linv_wr(struct rpcrdma_mr_seg *seg)
473{
474 struct rpcrdma_mw *mw = seg->rl_mw;
475 struct rpcrdma_frmr *f = &mw->frmr;
476 struct ib_send_wr *invalidate_wr;
477
478 f->fr_state = FRMR_IS_INVALID;
479 invalidate_wr = &f->fr_invwr;
480
481 memset(invalidate_wr, 0, sizeof(*invalidate_wr));
482 f->fr_cqe.done = frwr_wc_localinv;
483 invalidate_wr->wr_cqe = &f->fr_cqe;
484 invalidate_wr->opcode = IB_WR_LOCAL_INV;
485 invalidate_wr->ex.invalidate_rkey = f->fr_mr->rkey;
486
487 return invalidate_wr;
488}
489
490static void
491__frwr_dma_unmap(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg,
492 int rc)
493{
494 struct ib_device *device = r_xprt->rx_ia.ri_device;
495 struct rpcrdma_mw *mw = seg->rl_mw;
496 struct rpcrdma_frmr *f = &mw->frmr;
497
498 seg->rl_mw = NULL;
499
500 ib_dma_unmap_sg(device, f->sg, f->sg_nents, seg->mr_dir);
501
502 if (!rc)
503 rpcrdma_put_mw(r_xprt, mw);
504 else
505 __frwr_queue_recovery(mw);
506}
507
508/* Invalidate all memory regions that were registered for "req".
509 *
510 * Sleeps until it is safe for the host CPU to access the
511 * previously mapped memory regions.
512 */
513static void
514frwr_op_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req)
515{
516 struct ib_send_wr *invalidate_wrs, *pos, *prev, *bad_wr;
517 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
518 struct rpcrdma_mr_seg *seg;
519 unsigned int i, nchunks;
520 struct rpcrdma_frmr *f;
521 int rc;
522
523 dprintk("RPC: %s: req %p\n", __func__, req);
524
525 /* ORDER: Invalidate all of the req's MRs first
526 *
527 * Chain the LOCAL_INV Work Requests and post them with
528 * a single ib_post_send() call.
529 */
530 invalidate_wrs = pos = prev = NULL;
531 seg = NULL;
532 for (i = 0, nchunks = req->rl_nchunks; nchunks; nchunks--) {
533 seg = &req->rl_segments[i];
534
535 pos = __frwr_prepare_linv_wr(seg);
536
537 if (!invalidate_wrs)
538 invalidate_wrs = pos;
539 else
540 prev->next = pos;
541 prev = pos;
542
543 i += seg->mr_nsegs;
544 }
545 f = &seg->rl_mw->frmr;
546
547 /* Strong send queue ordering guarantees that when the
548 * last WR in the chain completes, all WRs in the chain
549 * are complete.
550 */
551 f->fr_invwr.send_flags = IB_SEND_SIGNALED;
552 f->fr_cqe.done = frwr_wc_localinv_wake;
553 reinit_completion(&f->fr_linv_done);
554 INIT_CQCOUNT(&r_xprt->rx_ep);
555
556 /* Transport disconnect drains the receive CQ before it
557 * replaces the QP. The RPC reply handler won't call us
558 * unless ri_id->qp is a valid pointer.
559 */
560 rc = ib_post_send(ia->ri_id->qp, invalidate_wrs, &bad_wr);
561 if (rc) {
562 pr_warn("%s: ib_post_send failed %i\n", __func__, rc);
563 rdma_disconnect(ia->ri_id);
564 goto unmap;
565 }
566
567 wait_for_completion(&f->fr_linv_done);
568
569 /* ORDER: Now DMA unmap all of the req's MRs, and return
570 * them to the free MW list.
571 */
572unmap:
573 for (i = 0, nchunks = req->rl_nchunks; nchunks; nchunks--) {
574 seg = &req->rl_segments[i];
575
576 __frwr_dma_unmap(r_xprt, seg, rc);
577
578 i += seg->mr_nsegs;
579 seg->mr_nsegs = 0;
580 }
581
582 req->rl_nchunks = 0;
583}
584
585/* Post a LOCAL_INV Work Request to prevent further remote access
586 * via RDMA READ or RDMA WRITE.
587 */
588static int
589frwr_op_unmap(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg)
590{
591 struct rpcrdma_mr_seg *seg1 = seg;
592 struct rpcrdma_ia *ia = &r_xprt->rx_ia;
593 struct rpcrdma_mw *mw = seg1->rl_mw;
594 struct rpcrdma_frmr *frmr = &mw->frmr;
595 struct ib_send_wr *invalidate_wr, *bad_wr;
596 int rc, nsegs = seg->mr_nsegs;
597
598 dprintk("RPC: %s: FRMR %p\n", __func__, mw);
599
600 seg1->rl_mw = NULL;
601 frmr->fr_state = FRMR_IS_INVALID;
602 invalidate_wr = &mw->frmr.fr_invwr;
603
604 memset(invalidate_wr, 0, sizeof(*invalidate_wr));
605 frmr->fr_cqe.done = frwr_wc_localinv;
606 invalidate_wr->wr_cqe = &frmr->fr_cqe;
607 invalidate_wr->opcode = IB_WR_LOCAL_INV;
608 invalidate_wr->ex.invalidate_rkey = frmr->fr_mr->rkey;
609 DECR_CQCOUNT(&r_xprt->rx_ep);
610
611 ib_dma_unmap_sg(ia->ri_device, frmr->sg, frmr->sg_nents, seg1->mr_dir);
612 read_lock(&ia->ri_qplock);
613 rc = ib_post_send(ia->ri_id->qp, invalidate_wr, &bad_wr);
614 read_unlock(&ia->ri_qplock);
615 if (rc)
616 goto out_err;
617
618 rpcrdma_put_mw(r_xprt, mw);
619 return nsegs;
620
621out_err:
622 dprintk("RPC: %s: ib_post_send status %i\n", __func__, rc);
623 __frwr_queue_recovery(mw);
624 return nsegs;
625}
626
627static void
628frwr_op_destroy(struct rpcrdma_buffer *buf)
629{
630 struct rpcrdma_mw *r;
631
632 /* Ensure stale MWs for "buf" are no longer in flight */
633 flush_workqueue(frwr_recovery_wq);
634
635 while (!list_empty(&buf->rb_all)) {
636 r = list_entry(buf->rb_all.next, struct rpcrdma_mw, mw_all);
637 list_del(&r->mw_all);
638 __frwr_release(r);
639 kfree(r);
640 }
641}
642
643const struct rpcrdma_memreg_ops rpcrdma_frwr_memreg_ops = {
644 .ro_map = frwr_op_map,
645 .ro_unmap_sync = frwr_op_unmap_sync,
646 .ro_unmap = frwr_op_unmap,
647 .ro_open = frwr_op_open,
648 .ro_maxpages = frwr_op_maxpages,
649 .ro_init = frwr_op_init,
650 .ro_destroy = frwr_op_destroy,
651 .ro_displayname = "frwr",
652};