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-rw-r--r--net/rds/iw_rdma.c888
1 files changed, 888 insertions, 0 deletions
diff --git a/net/rds/iw_rdma.c b/net/rds/iw_rdma.c
new file mode 100644
index 000000000000..1c02a8f952d0
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+++ b/net/rds/iw_rdma.c
@@ -0,0 +1,888 @@
1/*
2 * Copyright (c) 2006 Oracle. 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
8 * OpenIB.org BSD license below:
9 *
10 * Redistribution and use in source and binary forms, with or
11 * without modification, are permitted provided that the following
12 * conditions are met:
13 *
14 * - Redistributions of source code must retain the above
15 * copyright notice, this list of conditions and the following
16 * 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
21 * provided with the distribution.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 * SOFTWARE.
31 *
32 */
33#include <linux/kernel.h>
34
35#include "rds.h"
36#include "rdma.h"
37#include "iw.h"
38
39
40/*
41 * This is stored as mr->r_trans_private.
42 */
43struct rds_iw_mr {
44 struct rds_iw_device *device;
45 struct rds_iw_mr_pool *pool;
46 struct rdma_cm_id *cm_id;
47
48 struct ib_mr *mr;
49 struct ib_fast_reg_page_list *page_list;
50
51 struct rds_iw_mapping mapping;
52 unsigned char remap_count;
53};
54
55/*
56 * Our own little MR pool
57 */
58struct rds_iw_mr_pool {
59 struct rds_iw_device *device; /* back ptr to the device that owns us */
60
61 struct mutex flush_lock; /* serialize fmr invalidate */
62 struct work_struct flush_worker; /* flush worker */
63
64 spinlock_t list_lock; /* protect variables below */
65 atomic_t item_count; /* total # of MRs */
66 atomic_t dirty_count; /* # dirty of MRs */
67 struct list_head dirty_list; /* dirty mappings */
68 struct list_head clean_list; /* unused & unamapped MRs */
69 atomic_t free_pinned; /* memory pinned by free MRs */
70 unsigned long max_message_size; /* in pages */
71 unsigned long max_items;
72 unsigned long max_items_soft;
73 unsigned long max_free_pinned;
74 int max_pages;
75};
76
77static int rds_iw_flush_mr_pool(struct rds_iw_mr_pool *pool, int free_all);
78static void rds_iw_mr_pool_flush_worker(struct work_struct *work);
79static int rds_iw_init_fastreg(struct rds_iw_mr_pool *pool, struct rds_iw_mr *ibmr);
80static int rds_iw_map_fastreg(struct rds_iw_mr_pool *pool,
81 struct rds_iw_mr *ibmr,
82 struct scatterlist *sg, unsigned int nents);
83static void rds_iw_free_fastreg(struct rds_iw_mr_pool *pool, struct rds_iw_mr *ibmr);
84static unsigned int rds_iw_unmap_fastreg_list(struct rds_iw_mr_pool *pool,
85 struct list_head *unmap_list,
86 struct list_head *kill_list);
87static void rds_iw_destroy_fastreg(struct rds_iw_mr_pool *pool, struct rds_iw_mr *ibmr);
88
89static int rds_iw_get_device(struct rds_sock *rs, struct rds_iw_device **rds_iwdev, struct rdma_cm_id **cm_id)
90{
91 struct rds_iw_device *iwdev;
92 struct rds_iw_cm_id *i_cm_id;
93
94 *rds_iwdev = NULL;
95 *cm_id = NULL;
96
97 list_for_each_entry(iwdev, &rds_iw_devices, list) {
98 spin_lock_irq(&iwdev->spinlock);
99 list_for_each_entry(i_cm_id, &iwdev->cm_id_list, list) {
100 struct sockaddr_in *src_addr, *dst_addr;
101
102 src_addr = (struct sockaddr_in *)&i_cm_id->cm_id->route.addr.src_addr;
103 dst_addr = (struct sockaddr_in *)&i_cm_id->cm_id->route.addr.dst_addr;
104
105 rdsdebug("local ipaddr = %x port %d, "
106 "remote ipaddr = %x port %d"
107 "..looking for %x port %d, "
108 "remote ipaddr = %x port %d\n",
109 src_addr->sin_addr.s_addr,
110 src_addr->sin_port,
111 dst_addr->sin_addr.s_addr,
112 dst_addr->sin_port,
113 rs->rs_bound_addr,
114 rs->rs_bound_port,
115 rs->rs_conn_addr,
116 rs->rs_conn_port);
117#ifdef WORKING_TUPLE_DETECTION
118 if (src_addr->sin_addr.s_addr == rs->rs_bound_addr &&
119 src_addr->sin_port == rs->rs_bound_port &&
120 dst_addr->sin_addr.s_addr == rs->rs_conn_addr &&
121 dst_addr->sin_port == rs->rs_conn_port) {
122#else
123 /* FIXME - needs to compare the local and remote
124 * ipaddr/port tuple, but the ipaddr is the only
125 * available infomation in the rds_sock (as the rest are
126 * zero'ed. It doesn't appear to be properly populated
127 * during connection setup...
128 */
129 if (src_addr->sin_addr.s_addr == rs->rs_bound_addr) {
130#endif
131 spin_unlock_irq(&iwdev->spinlock);
132 *rds_iwdev = iwdev;
133 *cm_id = i_cm_id->cm_id;
134 return 0;
135 }
136 }
137 spin_unlock_irq(&iwdev->spinlock);
138 }
139
140 return 1;
141}
142
143static int rds_iw_add_cm_id(struct rds_iw_device *rds_iwdev, struct rdma_cm_id *cm_id)
144{
145 struct rds_iw_cm_id *i_cm_id;
146
147 i_cm_id = kmalloc(sizeof *i_cm_id, GFP_KERNEL);
148 if (!i_cm_id)
149 return -ENOMEM;
150
151 i_cm_id->cm_id = cm_id;
152
153 spin_lock_irq(&rds_iwdev->spinlock);
154 list_add_tail(&i_cm_id->list, &rds_iwdev->cm_id_list);
155 spin_unlock_irq(&rds_iwdev->spinlock);
156
157 return 0;
158}
159
160void rds_iw_remove_cm_id(struct rds_iw_device *rds_iwdev, struct rdma_cm_id *cm_id)
161{
162 struct rds_iw_cm_id *i_cm_id;
163
164 spin_lock_irq(&rds_iwdev->spinlock);
165 list_for_each_entry(i_cm_id, &rds_iwdev->cm_id_list, list) {
166 if (i_cm_id->cm_id == cm_id) {
167 list_del(&i_cm_id->list);
168 kfree(i_cm_id);
169 break;
170 }
171 }
172 spin_unlock_irq(&rds_iwdev->spinlock);
173}
174
175
176int rds_iw_update_cm_id(struct rds_iw_device *rds_iwdev, struct rdma_cm_id *cm_id)
177{
178 struct sockaddr_in *src_addr, *dst_addr;
179 struct rds_iw_device *rds_iwdev_old;
180 struct rds_sock rs;
181 struct rdma_cm_id *pcm_id;
182 int rc;
183
184 src_addr = (struct sockaddr_in *)&cm_id->route.addr.src_addr;
185 dst_addr = (struct sockaddr_in *)&cm_id->route.addr.dst_addr;
186
187 rs.rs_bound_addr = src_addr->sin_addr.s_addr;
188 rs.rs_bound_port = src_addr->sin_port;
189 rs.rs_conn_addr = dst_addr->sin_addr.s_addr;
190 rs.rs_conn_port = dst_addr->sin_port;
191
192 rc = rds_iw_get_device(&rs, &rds_iwdev_old, &pcm_id);
193 if (rc)
194 rds_iw_remove_cm_id(rds_iwdev, cm_id);
195
196 return rds_iw_add_cm_id(rds_iwdev, cm_id);
197}
198
199int rds_iw_add_conn(struct rds_iw_device *rds_iwdev, struct rds_connection *conn)
200{
201 struct rds_iw_connection *ic = conn->c_transport_data;
202
203 /* conn was previously on the nodev_conns_list */
204 spin_lock_irq(&iw_nodev_conns_lock);
205 BUG_ON(list_empty(&iw_nodev_conns));
206 BUG_ON(list_empty(&ic->iw_node));
207 list_del(&ic->iw_node);
208 spin_unlock_irq(&iw_nodev_conns_lock);
209
210 spin_lock_irq(&rds_iwdev->spinlock);
211 list_add_tail(&ic->iw_node, &rds_iwdev->conn_list);
212 spin_unlock_irq(&rds_iwdev->spinlock);
213
214 ic->rds_iwdev = rds_iwdev;
215
216 return 0;
217}
218
219void rds_iw_remove_nodev_conns(void)
220{
221 struct rds_iw_connection *ic, *_ic;
222 LIST_HEAD(tmp_list);
223
224 /* avoid calling conn_destroy with irqs off */
225 spin_lock_irq(&iw_nodev_conns_lock);
226 list_splice(&iw_nodev_conns, &tmp_list);
227 INIT_LIST_HEAD(&iw_nodev_conns);
228 spin_unlock_irq(&iw_nodev_conns_lock);
229
230 list_for_each_entry_safe(ic, _ic, &tmp_list, iw_node) {
231 if (ic->conn->c_passive)
232 rds_conn_destroy(ic->conn->c_passive);
233 rds_conn_destroy(ic->conn);
234 }
235}
236
237void rds_iw_remove_conns(struct rds_iw_device *rds_iwdev)
238{
239 struct rds_iw_connection *ic, *_ic;
240 LIST_HEAD(tmp_list);
241
242 /* avoid calling conn_destroy with irqs off */
243 spin_lock_irq(&rds_iwdev->spinlock);
244 list_splice(&rds_iwdev->conn_list, &tmp_list);
245 INIT_LIST_HEAD(&rds_iwdev->conn_list);
246 spin_unlock_irq(&rds_iwdev->spinlock);
247
248 list_for_each_entry_safe(ic, _ic, &tmp_list, iw_node) {
249 if (ic->conn->c_passive)
250 rds_conn_destroy(ic->conn->c_passive);
251 rds_conn_destroy(ic->conn);
252 }
253}
254
255static void rds_iw_set_scatterlist(struct rds_iw_scatterlist *sg,
256 struct scatterlist *list, unsigned int sg_len)
257{
258 sg->list = list;
259 sg->len = sg_len;
260 sg->dma_len = 0;
261 sg->dma_npages = 0;
262 sg->bytes = 0;
263}
264
265static u64 *rds_iw_map_scatterlist(struct rds_iw_device *rds_iwdev,
266 struct rds_iw_scatterlist *sg,
267 unsigned int dma_page_shift)
268{
269 struct ib_device *dev = rds_iwdev->dev;
270 u64 *dma_pages = NULL;
271 u64 dma_mask;
272 unsigned int dma_page_size;
273 int i, j, ret;
274
275 dma_page_size = 1 << dma_page_shift;
276 dma_mask = dma_page_size - 1;
277
278 WARN_ON(sg->dma_len);
279
280 sg->dma_len = ib_dma_map_sg(dev, sg->list, sg->len, DMA_BIDIRECTIONAL);
281 if (unlikely(!sg->dma_len)) {
282 printk(KERN_WARNING "RDS/IW: dma_map_sg failed!\n");
283 return ERR_PTR(-EBUSY);
284 }
285
286 sg->bytes = 0;
287 sg->dma_npages = 0;
288
289 ret = -EINVAL;
290 for (i = 0; i < sg->dma_len; ++i) {
291 unsigned int dma_len = ib_sg_dma_len(dev, &sg->list[i]);
292 u64 dma_addr = ib_sg_dma_address(dev, &sg->list[i]);
293 u64 end_addr;
294
295 sg->bytes += dma_len;
296
297 end_addr = dma_addr + dma_len;
298 if (dma_addr & dma_mask) {
299 if (i > 0)
300 goto out_unmap;
301 dma_addr &= ~dma_mask;
302 }
303 if (end_addr & dma_mask) {
304 if (i < sg->dma_len - 1)
305 goto out_unmap;
306 end_addr = (end_addr + dma_mask) & ~dma_mask;
307 }
308
309 sg->dma_npages += (end_addr - dma_addr) >> dma_page_shift;
310 }
311
312 /* Now gather the dma addrs into one list */
313 if (sg->dma_npages > fastreg_message_size)
314 goto out_unmap;
315
316 dma_pages = kmalloc(sizeof(u64) * sg->dma_npages, GFP_ATOMIC);
317 if (!dma_pages) {
318 ret = -ENOMEM;
319 goto out_unmap;
320 }
321
322 for (i = j = 0; i < sg->dma_len; ++i) {
323 unsigned int dma_len = ib_sg_dma_len(dev, &sg->list[i]);
324 u64 dma_addr = ib_sg_dma_address(dev, &sg->list[i]);
325 u64 end_addr;
326
327 end_addr = dma_addr + dma_len;
328 dma_addr &= ~dma_mask;
329 for (; dma_addr < end_addr; dma_addr += dma_page_size)
330 dma_pages[j++] = dma_addr;
331 BUG_ON(j > sg->dma_npages);
332 }
333
334 return dma_pages;
335
336out_unmap:
337 ib_dma_unmap_sg(rds_iwdev->dev, sg->list, sg->len, DMA_BIDIRECTIONAL);
338 sg->dma_len = 0;
339 kfree(dma_pages);
340 return ERR_PTR(ret);
341}
342
343
344struct rds_iw_mr_pool *rds_iw_create_mr_pool(struct rds_iw_device *rds_iwdev)
345{
346 struct rds_iw_mr_pool *pool;
347
348 pool = kzalloc(sizeof(*pool), GFP_KERNEL);
349 if (!pool) {
350 printk(KERN_WARNING "RDS/IW: rds_iw_create_mr_pool alloc error\n");
351 return ERR_PTR(-ENOMEM);
352 }
353
354 pool->device = rds_iwdev;
355 INIT_LIST_HEAD(&pool->dirty_list);
356 INIT_LIST_HEAD(&pool->clean_list);
357 mutex_init(&pool->flush_lock);
358 spin_lock_init(&pool->list_lock);
359 INIT_WORK(&pool->flush_worker, rds_iw_mr_pool_flush_worker);
360
361 pool->max_message_size = fastreg_message_size;
362 pool->max_items = fastreg_pool_size;
363 pool->max_free_pinned = pool->max_items * pool->max_message_size / 4;
364 pool->max_pages = fastreg_message_size;
365
366 /* We never allow more than max_items MRs to be allocated.
367 * When we exceed more than max_items_soft, we start freeing
368 * items more aggressively.
369 * Make sure that max_items > max_items_soft > max_items / 2
370 */
371 pool->max_items_soft = pool->max_items * 3 / 4;
372
373 return pool;
374}
375
376void rds_iw_get_mr_info(struct rds_iw_device *rds_iwdev, struct rds_info_rdma_connection *iinfo)
377{
378 struct rds_iw_mr_pool *pool = rds_iwdev->mr_pool;
379
380 iinfo->rdma_mr_max = pool->max_items;
381 iinfo->rdma_mr_size = pool->max_pages;
382}
383
384void rds_iw_destroy_mr_pool(struct rds_iw_mr_pool *pool)
385{
386 flush_workqueue(rds_wq);
387 rds_iw_flush_mr_pool(pool, 1);
388 BUG_ON(atomic_read(&pool->item_count));
389 BUG_ON(atomic_read(&pool->free_pinned));
390 kfree(pool);
391}
392
393static inline struct rds_iw_mr *rds_iw_reuse_fmr(struct rds_iw_mr_pool *pool)
394{
395 struct rds_iw_mr *ibmr = NULL;
396 unsigned long flags;
397
398 spin_lock_irqsave(&pool->list_lock, flags);
399 if (!list_empty(&pool->clean_list)) {
400 ibmr = list_entry(pool->clean_list.next, struct rds_iw_mr, mapping.m_list);
401 list_del_init(&ibmr->mapping.m_list);
402 }
403 spin_unlock_irqrestore(&pool->list_lock, flags);
404
405 return ibmr;
406}
407
408static struct rds_iw_mr *rds_iw_alloc_mr(struct rds_iw_device *rds_iwdev)
409{
410 struct rds_iw_mr_pool *pool = rds_iwdev->mr_pool;
411 struct rds_iw_mr *ibmr = NULL;
412 int err = 0, iter = 0;
413
414 while (1) {
415 ibmr = rds_iw_reuse_fmr(pool);
416 if (ibmr)
417 return ibmr;
418
419 /* No clean MRs - now we have the choice of either
420 * allocating a fresh MR up to the limit imposed by the
421 * driver, or flush any dirty unused MRs.
422 * We try to avoid stalling in the send path if possible,
423 * so we allocate as long as we're allowed to.
424 *
425 * We're fussy with enforcing the FMR limit, though. If the driver
426 * tells us we can't use more than N fmrs, we shouldn't start
427 * arguing with it */
428 if (atomic_inc_return(&pool->item_count) <= pool->max_items)
429 break;
430
431 atomic_dec(&pool->item_count);
432
433 if (++iter > 2) {
434 rds_iw_stats_inc(s_iw_rdma_mr_pool_depleted);
435 return ERR_PTR(-EAGAIN);
436 }
437
438 /* We do have some empty MRs. Flush them out. */
439 rds_iw_stats_inc(s_iw_rdma_mr_pool_wait);
440 rds_iw_flush_mr_pool(pool, 0);
441 }
442
443 ibmr = kzalloc(sizeof(*ibmr), GFP_KERNEL);
444 if (!ibmr) {
445 err = -ENOMEM;
446 goto out_no_cigar;
447 }
448
449 spin_lock_init(&ibmr->mapping.m_lock);
450 INIT_LIST_HEAD(&ibmr->mapping.m_list);
451 ibmr->mapping.m_mr = ibmr;
452
453 err = rds_iw_init_fastreg(pool, ibmr);
454 if (err)
455 goto out_no_cigar;
456
457 rds_iw_stats_inc(s_iw_rdma_mr_alloc);
458 return ibmr;
459
460out_no_cigar:
461 if (ibmr) {
462 rds_iw_destroy_fastreg(pool, ibmr);
463 kfree(ibmr);
464 }
465 atomic_dec(&pool->item_count);
466 return ERR_PTR(err);
467}
468
469void rds_iw_sync_mr(void *trans_private, int direction)
470{
471 struct rds_iw_mr *ibmr = trans_private;
472 struct rds_iw_device *rds_iwdev = ibmr->device;
473
474 switch (direction) {
475 case DMA_FROM_DEVICE:
476 ib_dma_sync_sg_for_cpu(rds_iwdev->dev, ibmr->mapping.m_sg.list,
477 ibmr->mapping.m_sg.dma_len, DMA_BIDIRECTIONAL);
478 break;
479 case DMA_TO_DEVICE:
480 ib_dma_sync_sg_for_device(rds_iwdev->dev, ibmr->mapping.m_sg.list,
481 ibmr->mapping.m_sg.dma_len, DMA_BIDIRECTIONAL);
482 break;
483 }
484}
485
486static inline unsigned int rds_iw_flush_goal(struct rds_iw_mr_pool *pool, int free_all)
487{
488 unsigned int item_count;
489
490 item_count = atomic_read(&pool->item_count);
491 if (free_all)
492 return item_count;
493
494 return 0;
495}
496
497/*
498 * Flush our pool of MRs.
499 * At a minimum, all currently unused MRs are unmapped.
500 * If the number of MRs allocated exceeds the limit, we also try
501 * to free as many MRs as needed to get back to this limit.
502 */
503static int rds_iw_flush_mr_pool(struct rds_iw_mr_pool *pool, int free_all)
504{
505 struct rds_iw_mr *ibmr, *next;
506 LIST_HEAD(unmap_list);
507 LIST_HEAD(kill_list);
508 unsigned long flags;
509 unsigned int nfreed = 0, ncleaned = 0, free_goal;
510 int ret = 0;
511
512 rds_iw_stats_inc(s_iw_rdma_mr_pool_flush);
513
514 mutex_lock(&pool->flush_lock);
515
516 spin_lock_irqsave(&pool->list_lock, flags);
517 /* Get the list of all mappings to be destroyed */
518 list_splice_init(&pool->dirty_list, &unmap_list);
519 if (free_all)
520 list_splice_init(&pool->clean_list, &kill_list);
521 spin_unlock_irqrestore(&pool->list_lock, flags);
522
523 free_goal = rds_iw_flush_goal(pool, free_all);
524
525 /* Batched invalidate of dirty MRs.
526 * For FMR based MRs, the mappings on the unmap list are
527 * actually members of an ibmr (ibmr->mapping). They either
528 * migrate to the kill_list, or have been cleaned and should be
529 * moved to the clean_list.
530 * For fastregs, they will be dynamically allocated, and
531 * will be destroyed by the unmap function.
532 */
533 if (!list_empty(&unmap_list)) {
534 ncleaned = rds_iw_unmap_fastreg_list(pool, &unmap_list, &kill_list);
535 /* If we've been asked to destroy all MRs, move those
536 * that were simply cleaned to the kill list */
537 if (free_all)
538 list_splice_init(&unmap_list, &kill_list);
539 }
540
541 /* Destroy any MRs that are past their best before date */
542 list_for_each_entry_safe(ibmr, next, &kill_list, mapping.m_list) {
543 rds_iw_stats_inc(s_iw_rdma_mr_free);
544 list_del(&ibmr->mapping.m_list);
545 rds_iw_destroy_fastreg(pool, ibmr);
546 kfree(ibmr);
547 nfreed++;
548 }
549
550 /* Anything that remains are laundered ibmrs, which we can add
551 * back to the clean list. */
552 if (!list_empty(&unmap_list)) {
553 spin_lock_irqsave(&pool->list_lock, flags);
554 list_splice(&unmap_list, &pool->clean_list);
555 spin_unlock_irqrestore(&pool->list_lock, flags);
556 }
557
558 atomic_sub(ncleaned, &pool->dirty_count);
559 atomic_sub(nfreed, &pool->item_count);
560
561 mutex_unlock(&pool->flush_lock);
562 return ret;
563}
564
565static void rds_iw_mr_pool_flush_worker(struct work_struct *work)
566{
567 struct rds_iw_mr_pool *pool = container_of(work, struct rds_iw_mr_pool, flush_worker);
568
569 rds_iw_flush_mr_pool(pool, 0);
570}
571
572void rds_iw_free_mr(void *trans_private, int invalidate)
573{
574 struct rds_iw_mr *ibmr = trans_private;
575 struct rds_iw_mr_pool *pool = ibmr->device->mr_pool;
576
577 rdsdebug("RDS/IW: free_mr nents %u\n", ibmr->mapping.m_sg.len);
578 if (!pool)
579 return;
580
581 /* Return it to the pool's free list */
582 rds_iw_free_fastreg(pool, ibmr);
583
584 /* If we've pinned too many pages, request a flush */
585 if (atomic_read(&pool->free_pinned) >= pool->max_free_pinned
586 || atomic_read(&pool->dirty_count) >= pool->max_items / 10)
587 queue_work(rds_wq, &pool->flush_worker);
588
589 if (invalidate) {
590 if (likely(!in_interrupt())) {
591 rds_iw_flush_mr_pool(pool, 0);
592 } else {
593 /* We get here if the user created a MR marked
594 * as use_once and invalidate at the same time. */
595 queue_work(rds_wq, &pool->flush_worker);
596 }
597 }
598}
599
600void rds_iw_flush_mrs(void)
601{
602 struct rds_iw_device *rds_iwdev;
603
604 list_for_each_entry(rds_iwdev, &rds_iw_devices, list) {
605 struct rds_iw_mr_pool *pool = rds_iwdev->mr_pool;
606
607 if (pool)
608 rds_iw_flush_mr_pool(pool, 0);
609 }
610}
611
612void *rds_iw_get_mr(struct scatterlist *sg, unsigned long nents,
613 struct rds_sock *rs, u32 *key_ret)
614{
615 struct rds_iw_device *rds_iwdev;
616 struct rds_iw_mr *ibmr = NULL;
617 struct rdma_cm_id *cm_id;
618 int ret;
619
620 ret = rds_iw_get_device(rs, &rds_iwdev, &cm_id);
621 if (ret || !cm_id) {
622 ret = -ENODEV;
623 goto out;
624 }
625
626 if (!rds_iwdev->mr_pool) {
627 ret = -ENODEV;
628 goto out;
629 }
630
631 ibmr = rds_iw_alloc_mr(rds_iwdev);
632 if (IS_ERR(ibmr))
633 return ibmr;
634
635 ibmr->cm_id = cm_id;
636 ibmr->device = rds_iwdev;
637
638 ret = rds_iw_map_fastreg(rds_iwdev->mr_pool, ibmr, sg, nents);
639 if (ret == 0)
640 *key_ret = ibmr->mr->rkey;
641 else
642 printk(KERN_WARNING "RDS/IW: failed to map mr (errno=%d)\n", ret);
643
644out:
645 if (ret) {
646 if (ibmr)
647 rds_iw_free_mr(ibmr, 0);
648 ibmr = ERR_PTR(ret);
649 }
650 return ibmr;
651}
652
653/*
654 * iWARP fastreg handling
655 *
656 * The life cycle of a fastreg registration is a bit different from
657 * FMRs.
658 * The idea behind fastreg is to have one MR, to which we bind different
659 * mappings over time. To avoid stalling on the expensive map and invalidate
660 * operations, these operations are pipelined on the same send queue on
661 * which we want to send the message containing the r_key.
662 *
663 * This creates a bit of a problem for us, as we do not have the destination
664 * IP in GET_MR, so the connection must be setup prior to the GET_MR call for
665 * RDMA to be correctly setup. If a fastreg request is present, rds_iw_xmit
666 * will try to queue a LOCAL_INV (if needed) and a FAST_REG_MR work request
667 * before queuing the SEND. When completions for these arrive, they are
668 * dispatched to the MR has a bit set showing that RDMa can be performed.
669 *
670 * There is another interesting aspect that's related to invalidation.
671 * The application can request that a mapping is invalidated in FREE_MR.
672 * The expectation there is that this invalidation step includes ALL
673 * PREVIOUSLY FREED MRs.
674 */
675static int rds_iw_init_fastreg(struct rds_iw_mr_pool *pool,
676 struct rds_iw_mr *ibmr)
677{
678 struct rds_iw_device *rds_iwdev = pool->device;
679 struct ib_fast_reg_page_list *page_list = NULL;
680 struct ib_mr *mr;
681 int err;
682
683 mr = ib_alloc_fast_reg_mr(rds_iwdev->pd, pool->max_message_size);
684 if (IS_ERR(mr)) {
685 err = PTR_ERR(mr);
686
687 printk(KERN_WARNING "RDS/IW: ib_alloc_fast_reg_mr failed (err=%d)\n", err);
688 return err;
689 }
690
691 /* FIXME - this is overkill, but mapping->m_sg.dma_len/mapping->m_sg.dma_npages
692 * is not filled in.
693 */
694 page_list = ib_alloc_fast_reg_page_list(rds_iwdev->dev, pool->max_message_size);
695 if (IS_ERR(page_list)) {
696 err = PTR_ERR(page_list);
697
698 printk(KERN_WARNING "RDS/IW: ib_alloc_fast_reg_page_list failed (err=%d)\n", err);
699 ib_dereg_mr(mr);
700 return err;
701 }
702
703 ibmr->page_list = page_list;
704 ibmr->mr = mr;
705 return 0;
706}
707
708static int rds_iw_rdma_build_fastreg(struct rds_iw_mapping *mapping)
709{
710 struct rds_iw_mr *ibmr = mapping->m_mr;
711 struct ib_send_wr f_wr, *failed_wr;
712 int ret;
713
714 /*
715 * Perform a WR for the fast_reg_mr. Each individual page
716 * in the sg list is added to the fast reg page list and placed
717 * inside the fast_reg_mr WR. The key used is a rolling 8bit
718 * counter, which should guarantee uniqueness.
719 */
720 ib_update_fast_reg_key(ibmr->mr, ibmr->remap_count++);
721 mapping->m_rkey = ibmr->mr->rkey;
722
723 memset(&f_wr, 0, sizeof(f_wr));
724 f_wr.wr_id = RDS_IW_FAST_REG_WR_ID;
725 f_wr.opcode = IB_WR_FAST_REG_MR;
726 f_wr.wr.fast_reg.length = mapping->m_sg.bytes;
727 f_wr.wr.fast_reg.rkey = mapping->m_rkey;
728 f_wr.wr.fast_reg.page_list = ibmr->page_list;
729 f_wr.wr.fast_reg.page_list_len = mapping->m_sg.dma_len;
730 f_wr.wr.fast_reg.page_shift = ibmr->device->page_shift;
731 f_wr.wr.fast_reg.access_flags = IB_ACCESS_LOCAL_WRITE |
732 IB_ACCESS_REMOTE_READ |
733 IB_ACCESS_REMOTE_WRITE;
734 f_wr.wr.fast_reg.iova_start = 0;
735 f_wr.send_flags = IB_SEND_SIGNALED;
736
737 failed_wr = &f_wr;
738 ret = ib_post_send(ibmr->cm_id->qp, &f_wr, &failed_wr);
739 BUG_ON(failed_wr != &f_wr);
740 if (ret && printk_ratelimit())
741 printk(KERN_WARNING "RDS/IW: %s:%d ib_post_send returned %d\n",
742 __func__, __LINE__, ret);
743 return ret;
744}
745
746static int rds_iw_rdma_fastreg_inv(struct rds_iw_mr *ibmr)
747{
748 struct ib_send_wr s_wr, *failed_wr;
749 int ret = 0;
750
751 if (!ibmr->cm_id->qp || !ibmr->mr)
752 goto out;
753
754 memset(&s_wr, 0, sizeof(s_wr));
755 s_wr.wr_id = RDS_IW_LOCAL_INV_WR_ID;
756 s_wr.opcode = IB_WR_LOCAL_INV;
757 s_wr.ex.invalidate_rkey = ibmr->mr->rkey;
758 s_wr.send_flags = IB_SEND_SIGNALED;
759
760 failed_wr = &s_wr;
761 ret = ib_post_send(ibmr->cm_id->qp, &s_wr, &failed_wr);
762 if (ret && printk_ratelimit()) {
763 printk(KERN_WARNING "RDS/IW: %s:%d ib_post_send returned %d\n",
764 __func__, __LINE__, ret);
765 goto out;
766 }
767out:
768 return ret;
769}
770
771static int rds_iw_map_fastreg(struct rds_iw_mr_pool *pool,
772 struct rds_iw_mr *ibmr,
773 struct scatterlist *sg,
774 unsigned int sg_len)
775{
776 struct rds_iw_device *rds_iwdev = pool->device;
777 struct rds_iw_mapping *mapping = &ibmr->mapping;
778 u64 *dma_pages;
779 int i, ret = 0;
780
781 rds_iw_set_scatterlist(&mapping->m_sg, sg, sg_len);
782
783 dma_pages = rds_iw_map_scatterlist(rds_iwdev,
784 &mapping->m_sg,
785 rds_iwdev->page_shift);
786 if (IS_ERR(dma_pages)) {
787 ret = PTR_ERR(dma_pages);
788 dma_pages = NULL;
789 goto out;
790 }
791
792 if (mapping->m_sg.dma_len > pool->max_message_size) {
793 ret = -EMSGSIZE;
794 goto out;
795 }
796
797 for (i = 0; i < mapping->m_sg.dma_npages; ++i)
798 ibmr->page_list->page_list[i] = dma_pages[i];
799
800 ret = rds_iw_rdma_build_fastreg(mapping);
801 if (ret)
802 goto out;
803
804 rds_iw_stats_inc(s_iw_rdma_mr_used);
805
806out:
807 kfree(dma_pages);
808
809 return ret;
810}
811
812/*
813 * "Free" a fastreg MR.
814 */
815static void rds_iw_free_fastreg(struct rds_iw_mr_pool *pool,
816 struct rds_iw_mr *ibmr)
817{
818 unsigned long flags;
819 int ret;
820
821 if (!ibmr->mapping.m_sg.dma_len)
822 return;
823
824 ret = rds_iw_rdma_fastreg_inv(ibmr);
825 if (ret)
826 return;
827
828 /* Try to post the LOCAL_INV WR to the queue. */
829 spin_lock_irqsave(&pool->list_lock, flags);
830
831 list_add_tail(&ibmr->mapping.m_list, &pool->dirty_list);
832 atomic_add(ibmr->mapping.m_sg.len, &pool->free_pinned);
833 atomic_inc(&pool->dirty_count);
834
835 spin_unlock_irqrestore(&pool->list_lock, flags);
836}
837
838static unsigned int rds_iw_unmap_fastreg_list(struct rds_iw_mr_pool *pool,
839 struct list_head *unmap_list,
840 struct list_head *kill_list)
841{
842 struct rds_iw_mapping *mapping, *next;
843 unsigned int ncleaned = 0;
844 LIST_HEAD(laundered);
845
846 /* Batched invalidation of fastreg MRs.
847 * Why do we do it this way, even though we could pipeline unmap
848 * and remap? The reason is the application semantics - when the
849 * application requests an invalidation of MRs, it expects all
850 * previously released R_Keys to become invalid.
851 *
852 * If we implement MR reuse naively, we risk memory corruption
853 * (this has actually been observed). So the default behavior
854 * requires that a MR goes through an explicit unmap operation before
855 * we can reuse it again.
856 *
857 * We could probably improve on this a little, by allowing immediate
858 * reuse of a MR on the same socket (eg you could add small
859 * cache of unused MRs to strct rds_socket - GET_MR could grab one
860 * of these without requiring an explicit invalidate).
861 */
862 while (!list_empty(unmap_list)) {
863 unsigned long flags;
864
865 spin_lock_irqsave(&pool->list_lock, flags);
866 list_for_each_entry_safe(mapping, next, unmap_list, m_list) {
867 list_move(&mapping->m_list, &laundered);
868 ncleaned++;
869 }
870 spin_unlock_irqrestore(&pool->list_lock, flags);
871 }
872
873 /* Move all laundered mappings back to the unmap list.
874 * We do not kill any WRs right now - it doesn't seem the
875 * fastreg API has a max_remap limit. */
876 list_splice_init(&laundered, unmap_list);
877
878 return ncleaned;
879}
880
881static void rds_iw_destroy_fastreg(struct rds_iw_mr_pool *pool,
882 struct rds_iw_mr *ibmr)
883{
884 if (ibmr->page_list)
885 ib_free_fast_reg_page_list(ibmr->page_list);
886 if (ibmr->mr)
887 ib_dereg_mr(ibmr->mr);
888}
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-27 10:27:08 -0500