xref: /openbmc/linux/drivers/infiniband/hw/mlx5/mr.c (revision fcc8487d)
1 /*
2  * Copyright (c) 2013-2015, Mellanox Technologies. 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 
34 #include <linux/kref.h>
35 #include <linux/random.h>
36 #include <linux/debugfs.h>
37 #include <linux/export.h>
38 #include <linux/delay.h>
39 #include <rdma/ib_umem.h>
40 #include <rdma/ib_umem_odp.h>
41 #include <rdma/ib_verbs.h>
42 #include "mlx5_ib.h"
43 
44 enum {
45 	MAX_PENDING_REG_MR = 8,
46 };
47 
48 #define MLX5_UMR_ALIGN 2048
49 
50 static int clean_mr(struct mlx5_ib_mr *mr);
51 static int use_umr(struct mlx5_ib_dev *dev, int order);
52 static int unreg_umr(struct mlx5_ib_dev *dev, struct mlx5_ib_mr *mr);
53 
54 static int destroy_mkey(struct mlx5_ib_dev *dev, struct mlx5_ib_mr *mr)
55 {
56 	int err = mlx5_core_destroy_mkey(dev->mdev, &mr->mmkey);
57 
58 #ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
59 	/* Wait until all page fault handlers using the mr complete. */
60 	synchronize_srcu(&dev->mr_srcu);
61 #endif
62 
63 	return err;
64 }
65 
66 static int order2idx(struct mlx5_ib_dev *dev, int order)
67 {
68 	struct mlx5_mr_cache *cache = &dev->cache;
69 
70 	if (order < cache->ent[0].order)
71 		return 0;
72 	else
73 		return order - cache->ent[0].order;
74 }
75 
76 static bool use_umr_mtt_update(struct mlx5_ib_mr *mr, u64 start, u64 length)
77 {
78 	return ((u64)1 << mr->order) * MLX5_ADAPTER_PAGE_SIZE >=
79 		length + (start & (MLX5_ADAPTER_PAGE_SIZE - 1));
80 }
81 
82 #ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
83 static void update_odp_mr(struct mlx5_ib_mr *mr)
84 {
85 	if (mr->umem->odp_data) {
86 		/*
87 		 * This barrier prevents the compiler from moving the
88 		 * setting of umem->odp_data->private to point to our
89 		 * MR, before reg_umr finished, to ensure that the MR
90 		 * initialization have finished before starting to
91 		 * handle invalidations.
92 		 */
93 		smp_wmb();
94 		mr->umem->odp_data->private = mr;
95 		/*
96 		 * Make sure we will see the new
97 		 * umem->odp_data->private value in the invalidation
98 		 * routines, before we can get page faults on the
99 		 * MR. Page faults can happen once we put the MR in
100 		 * the tree, below this line. Without the barrier,
101 		 * there can be a fault handling and an invalidation
102 		 * before umem->odp_data->private == mr is visible to
103 		 * the invalidation handler.
104 		 */
105 		smp_wmb();
106 	}
107 }
108 #endif
109 
110 static void reg_mr_callback(int status, void *context)
111 {
112 	struct mlx5_ib_mr *mr = context;
113 	struct mlx5_ib_dev *dev = mr->dev;
114 	struct mlx5_mr_cache *cache = &dev->cache;
115 	int c = order2idx(dev, mr->order);
116 	struct mlx5_cache_ent *ent = &cache->ent[c];
117 	u8 key;
118 	unsigned long flags;
119 	struct mlx5_mkey_table *table = &dev->mdev->priv.mkey_table;
120 	int err;
121 
122 	spin_lock_irqsave(&ent->lock, flags);
123 	ent->pending--;
124 	spin_unlock_irqrestore(&ent->lock, flags);
125 	if (status) {
126 		mlx5_ib_warn(dev, "async reg mr failed. status %d\n", status);
127 		kfree(mr);
128 		dev->fill_delay = 1;
129 		mod_timer(&dev->delay_timer, jiffies + HZ);
130 		return;
131 	}
132 
133 	mr->mmkey.type = MLX5_MKEY_MR;
134 	spin_lock_irqsave(&dev->mdev->priv.mkey_lock, flags);
135 	key = dev->mdev->priv.mkey_key++;
136 	spin_unlock_irqrestore(&dev->mdev->priv.mkey_lock, flags);
137 	mr->mmkey.key = mlx5_idx_to_mkey(MLX5_GET(create_mkey_out, mr->out, mkey_index)) | key;
138 
139 	cache->last_add = jiffies;
140 
141 	spin_lock_irqsave(&ent->lock, flags);
142 	list_add_tail(&mr->list, &ent->head);
143 	ent->cur++;
144 	ent->size++;
145 	spin_unlock_irqrestore(&ent->lock, flags);
146 
147 	write_lock_irqsave(&table->lock, flags);
148 	err = radix_tree_insert(&table->tree, mlx5_base_mkey(mr->mmkey.key),
149 				&mr->mmkey);
150 	if (err)
151 		pr_err("Error inserting to mkey tree. 0x%x\n", -err);
152 	write_unlock_irqrestore(&table->lock, flags);
153 
154 	if (!completion_done(&ent->compl))
155 		complete(&ent->compl);
156 }
157 
158 static int add_keys(struct mlx5_ib_dev *dev, int c, int num)
159 {
160 	struct mlx5_mr_cache *cache = &dev->cache;
161 	struct mlx5_cache_ent *ent = &cache->ent[c];
162 	int inlen = MLX5_ST_SZ_BYTES(create_mkey_in);
163 	struct mlx5_ib_mr *mr;
164 	void *mkc;
165 	u32 *in;
166 	int err = 0;
167 	int i;
168 
169 	in = kzalloc(inlen, GFP_KERNEL);
170 	if (!in)
171 		return -ENOMEM;
172 
173 	mkc = MLX5_ADDR_OF(create_mkey_in, in, memory_key_mkey_entry);
174 	for (i = 0; i < num; i++) {
175 		if (ent->pending >= MAX_PENDING_REG_MR) {
176 			err = -EAGAIN;
177 			break;
178 		}
179 
180 		mr = kzalloc(sizeof(*mr), GFP_KERNEL);
181 		if (!mr) {
182 			err = -ENOMEM;
183 			break;
184 		}
185 		mr->order = ent->order;
186 		mr->umred = 1;
187 		mr->dev = dev;
188 
189 		MLX5_SET(mkc, mkc, free, 1);
190 		MLX5_SET(mkc, mkc, umr_en, 1);
191 		MLX5_SET(mkc, mkc, access_mode, ent->access_mode);
192 
193 		MLX5_SET(mkc, mkc, qpn, 0xffffff);
194 		MLX5_SET(mkc, mkc, translations_octword_size, ent->xlt);
195 		MLX5_SET(mkc, mkc, log_page_size, ent->page);
196 
197 		spin_lock_irq(&ent->lock);
198 		ent->pending++;
199 		spin_unlock_irq(&ent->lock);
200 		err = mlx5_core_create_mkey_cb(dev->mdev, &mr->mmkey,
201 					       in, inlen,
202 					       mr->out, sizeof(mr->out),
203 					       reg_mr_callback, mr);
204 		if (err) {
205 			spin_lock_irq(&ent->lock);
206 			ent->pending--;
207 			spin_unlock_irq(&ent->lock);
208 			mlx5_ib_warn(dev, "create mkey failed %d\n", err);
209 			kfree(mr);
210 			break;
211 		}
212 	}
213 
214 	kfree(in);
215 	return err;
216 }
217 
218 static void remove_keys(struct mlx5_ib_dev *dev, int c, int num)
219 {
220 	struct mlx5_mr_cache *cache = &dev->cache;
221 	struct mlx5_cache_ent *ent = &cache->ent[c];
222 	struct mlx5_ib_mr *mr;
223 	int err;
224 	int i;
225 
226 	for (i = 0; i < num; i++) {
227 		spin_lock_irq(&ent->lock);
228 		if (list_empty(&ent->head)) {
229 			spin_unlock_irq(&ent->lock);
230 			return;
231 		}
232 		mr = list_first_entry(&ent->head, struct mlx5_ib_mr, list);
233 		list_del(&mr->list);
234 		ent->cur--;
235 		ent->size--;
236 		spin_unlock_irq(&ent->lock);
237 		err = destroy_mkey(dev, mr);
238 		if (err)
239 			mlx5_ib_warn(dev, "failed destroy mkey\n");
240 		else
241 			kfree(mr);
242 	}
243 }
244 
245 static ssize_t size_write(struct file *filp, const char __user *buf,
246 			  size_t count, loff_t *pos)
247 {
248 	struct mlx5_cache_ent *ent = filp->private_data;
249 	struct mlx5_ib_dev *dev = ent->dev;
250 	char lbuf[20];
251 	u32 var;
252 	int err;
253 	int c;
254 
255 	if (copy_from_user(lbuf, buf, sizeof(lbuf)))
256 		return -EFAULT;
257 
258 	c = order2idx(dev, ent->order);
259 	lbuf[sizeof(lbuf) - 1] = 0;
260 
261 	if (sscanf(lbuf, "%u", &var) != 1)
262 		return -EINVAL;
263 
264 	if (var < ent->limit)
265 		return -EINVAL;
266 
267 	if (var > ent->size) {
268 		do {
269 			err = add_keys(dev, c, var - ent->size);
270 			if (err && err != -EAGAIN)
271 				return err;
272 
273 			usleep_range(3000, 5000);
274 		} while (err);
275 	} else if (var < ent->size) {
276 		remove_keys(dev, c, ent->size - var);
277 	}
278 
279 	return count;
280 }
281 
282 static ssize_t size_read(struct file *filp, char __user *buf, size_t count,
283 			 loff_t *pos)
284 {
285 	struct mlx5_cache_ent *ent = filp->private_data;
286 	char lbuf[20];
287 	int err;
288 
289 	if (*pos)
290 		return 0;
291 
292 	err = snprintf(lbuf, sizeof(lbuf), "%d\n", ent->size);
293 	if (err < 0)
294 		return err;
295 
296 	if (copy_to_user(buf, lbuf, err))
297 		return -EFAULT;
298 
299 	*pos += err;
300 
301 	return err;
302 }
303 
304 static const struct file_operations size_fops = {
305 	.owner	= THIS_MODULE,
306 	.open	= simple_open,
307 	.write	= size_write,
308 	.read	= size_read,
309 };
310 
311 static ssize_t limit_write(struct file *filp, const char __user *buf,
312 			   size_t count, loff_t *pos)
313 {
314 	struct mlx5_cache_ent *ent = filp->private_data;
315 	struct mlx5_ib_dev *dev = ent->dev;
316 	char lbuf[20];
317 	u32 var;
318 	int err;
319 	int c;
320 
321 	if (copy_from_user(lbuf, buf, sizeof(lbuf)))
322 		return -EFAULT;
323 
324 	c = order2idx(dev, ent->order);
325 	lbuf[sizeof(lbuf) - 1] = 0;
326 
327 	if (sscanf(lbuf, "%u", &var) != 1)
328 		return -EINVAL;
329 
330 	if (var > ent->size)
331 		return -EINVAL;
332 
333 	ent->limit = var;
334 
335 	if (ent->cur < ent->limit) {
336 		err = add_keys(dev, c, 2 * ent->limit - ent->cur);
337 		if (err)
338 			return err;
339 	}
340 
341 	return count;
342 }
343 
344 static ssize_t limit_read(struct file *filp, char __user *buf, size_t count,
345 			  loff_t *pos)
346 {
347 	struct mlx5_cache_ent *ent = filp->private_data;
348 	char lbuf[20];
349 	int err;
350 
351 	if (*pos)
352 		return 0;
353 
354 	err = snprintf(lbuf, sizeof(lbuf), "%d\n", ent->limit);
355 	if (err < 0)
356 		return err;
357 
358 	if (copy_to_user(buf, lbuf, err))
359 		return -EFAULT;
360 
361 	*pos += err;
362 
363 	return err;
364 }
365 
366 static const struct file_operations limit_fops = {
367 	.owner	= THIS_MODULE,
368 	.open	= simple_open,
369 	.write	= limit_write,
370 	.read	= limit_read,
371 };
372 
373 static int someone_adding(struct mlx5_mr_cache *cache)
374 {
375 	int i;
376 
377 	for (i = 0; i < MAX_MR_CACHE_ENTRIES; i++) {
378 		if (cache->ent[i].cur < cache->ent[i].limit)
379 			return 1;
380 	}
381 
382 	return 0;
383 }
384 
385 static void __cache_work_func(struct mlx5_cache_ent *ent)
386 {
387 	struct mlx5_ib_dev *dev = ent->dev;
388 	struct mlx5_mr_cache *cache = &dev->cache;
389 	int i = order2idx(dev, ent->order);
390 	int err;
391 
392 	if (cache->stopped)
393 		return;
394 
395 	ent = &dev->cache.ent[i];
396 	if (ent->cur < 2 * ent->limit && !dev->fill_delay) {
397 		err = add_keys(dev, i, 1);
398 		if (ent->cur < 2 * ent->limit) {
399 			if (err == -EAGAIN) {
400 				mlx5_ib_dbg(dev, "returned eagain, order %d\n",
401 					    i + 2);
402 				queue_delayed_work(cache->wq, &ent->dwork,
403 						   msecs_to_jiffies(3));
404 			} else if (err) {
405 				mlx5_ib_warn(dev, "command failed order %d, err %d\n",
406 					     i + 2, err);
407 				queue_delayed_work(cache->wq, &ent->dwork,
408 						   msecs_to_jiffies(1000));
409 			} else {
410 				queue_work(cache->wq, &ent->work);
411 			}
412 		}
413 	} else if (ent->cur > 2 * ent->limit) {
414 		/*
415 		 * The remove_keys() logic is performed as garbage collection
416 		 * task. Such task is intended to be run when no other active
417 		 * processes are running.
418 		 *
419 		 * The need_resched() will return TRUE if there are user tasks
420 		 * to be activated in near future.
421 		 *
422 		 * In such case, we don't execute remove_keys() and postpone
423 		 * the garbage collection work to try to run in next cycle,
424 		 * in order to free CPU resources to other tasks.
425 		 */
426 		if (!need_resched() && !someone_adding(cache) &&
427 		    time_after(jiffies, cache->last_add + 300 * HZ)) {
428 			remove_keys(dev, i, 1);
429 			if (ent->cur > ent->limit)
430 				queue_work(cache->wq, &ent->work);
431 		} else {
432 			queue_delayed_work(cache->wq, &ent->dwork, 300 * HZ);
433 		}
434 	}
435 }
436 
437 static void delayed_cache_work_func(struct work_struct *work)
438 {
439 	struct mlx5_cache_ent *ent;
440 
441 	ent = container_of(work, struct mlx5_cache_ent, dwork.work);
442 	__cache_work_func(ent);
443 }
444 
445 static void cache_work_func(struct work_struct *work)
446 {
447 	struct mlx5_cache_ent *ent;
448 
449 	ent = container_of(work, struct mlx5_cache_ent, work);
450 	__cache_work_func(ent);
451 }
452 
453 struct mlx5_ib_mr *mlx5_mr_cache_alloc(struct mlx5_ib_dev *dev, int entry)
454 {
455 	struct mlx5_mr_cache *cache = &dev->cache;
456 	struct mlx5_cache_ent *ent;
457 	struct mlx5_ib_mr *mr;
458 	int err;
459 
460 	if (entry < 0 || entry >= MAX_MR_CACHE_ENTRIES) {
461 		mlx5_ib_err(dev, "cache entry %d is out of range\n", entry);
462 		return NULL;
463 	}
464 
465 	ent = &cache->ent[entry];
466 	while (1) {
467 		spin_lock_irq(&ent->lock);
468 		if (list_empty(&ent->head)) {
469 			spin_unlock_irq(&ent->lock);
470 
471 			err = add_keys(dev, entry, 1);
472 			if (err && err != -EAGAIN)
473 				return ERR_PTR(err);
474 
475 			wait_for_completion(&ent->compl);
476 		} else {
477 			mr = list_first_entry(&ent->head, struct mlx5_ib_mr,
478 					      list);
479 			list_del(&mr->list);
480 			ent->cur--;
481 			spin_unlock_irq(&ent->lock);
482 			if (ent->cur < ent->limit)
483 				queue_work(cache->wq, &ent->work);
484 			return mr;
485 		}
486 	}
487 }
488 
489 static struct mlx5_ib_mr *alloc_cached_mr(struct mlx5_ib_dev *dev, int order)
490 {
491 	struct mlx5_mr_cache *cache = &dev->cache;
492 	struct mlx5_ib_mr *mr = NULL;
493 	struct mlx5_cache_ent *ent;
494 	int c;
495 	int i;
496 
497 	c = order2idx(dev, order);
498 	if (c < 0 || c > MAX_UMR_CACHE_ENTRY) {
499 		mlx5_ib_warn(dev, "order %d, cache index %d\n", order, c);
500 		return NULL;
501 	}
502 
503 	for (i = c; i < MAX_UMR_CACHE_ENTRY; i++) {
504 		ent = &cache->ent[i];
505 
506 		mlx5_ib_dbg(dev, "order %d, cache index %d\n", ent->order, i);
507 
508 		spin_lock_irq(&ent->lock);
509 		if (!list_empty(&ent->head)) {
510 			mr = list_first_entry(&ent->head, struct mlx5_ib_mr,
511 					      list);
512 			list_del(&mr->list);
513 			ent->cur--;
514 			spin_unlock_irq(&ent->lock);
515 			if (ent->cur < ent->limit)
516 				queue_work(cache->wq, &ent->work);
517 			break;
518 		}
519 		spin_unlock_irq(&ent->lock);
520 
521 		queue_work(cache->wq, &ent->work);
522 	}
523 
524 	if (!mr)
525 		cache->ent[c].miss++;
526 
527 	return mr;
528 }
529 
530 void mlx5_mr_cache_free(struct mlx5_ib_dev *dev, struct mlx5_ib_mr *mr)
531 {
532 	struct mlx5_mr_cache *cache = &dev->cache;
533 	struct mlx5_cache_ent *ent;
534 	int shrink = 0;
535 	int c;
536 
537 	c = order2idx(dev, mr->order);
538 	if (c < 0 || c >= MAX_MR_CACHE_ENTRIES) {
539 		mlx5_ib_warn(dev, "order %d, cache index %d\n", mr->order, c);
540 		return;
541 	}
542 
543 	if (unreg_umr(dev, mr))
544 		return;
545 
546 	ent = &cache->ent[c];
547 	spin_lock_irq(&ent->lock);
548 	list_add_tail(&mr->list, &ent->head);
549 	ent->cur++;
550 	if (ent->cur > 2 * ent->limit)
551 		shrink = 1;
552 	spin_unlock_irq(&ent->lock);
553 
554 	if (shrink)
555 		queue_work(cache->wq, &ent->work);
556 }
557 
558 static void clean_keys(struct mlx5_ib_dev *dev, int c)
559 {
560 	struct mlx5_mr_cache *cache = &dev->cache;
561 	struct mlx5_cache_ent *ent = &cache->ent[c];
562 	struct mlx5_ib_mr *mr;
563 	int err;
564 
565 	cancel_delayed_work(&ent->dwork);
566 	while (1) {
567 		spin_lock_irq(&ent->lock);
568 		if (list_empty(&ent->head)) {
569 			spin_unlock_irq(&ent->lock);
570 			return;
571 		}
572 		mr = list_first_entry(&ent->head, struct mlx5_ib_mr, list);
573 		list_del(&mr->list);
574 		ent->cur--;
575 		ent->size--;
576 		spin_unlock_irq(&ent->lock);
577 		err = destroy_mkey(dev, mr);
578 		if (err)
579 			mlx5_ib_warn(dev, "failed destroy mkey\n");
580 		else
581 			kfree(mr);
582 	}
583 }
584 
585 static int mlx5_mr_cache_debugfs_init(struct mlx5_ib_dev *dev)
586 {
587 	struct mlx5_mr_cache *cache = &dev->cache;
588 	struct mlx5_cache_ent *ent;
589 	int i;
590 
591 	if (!mlx5_debugfs_root)
592 		return 0;
593 
594 	cache->root = debugfs_create_dir("mr_cache", dev->mdev->priv.dbg_root);
595 	if (!cache->root)
596 		return -ENOMEM;
597 
598 	for (i = 0; i < MAX_MR_CACHE_ENTRIES; i++) {
599 		ent = &cache->ent[i];
600 		sprintf(ent->name, "%d", ent->order);
601 		ent->dir = debugfs_create_dir(ent->name,  cache->root);
602 		if (!ent->dir)
603 			return -ENOMEM;
604 
605 		ent->fsize = debugfs_create_file("size", 0600, ent->dir, ent,
606 						 &size_fops);
607 		if (!ent->fsize)
608 			return -ENOMEM;
609 
610 		ent->flimit = debugfs_create_file("limit", 0600, ent->dir, ent,
611 						  &limit_fops);
612 		if (!ent->flimit)
613 			return -ENOMEM;
614 
615 		ent->fcur = debugfs_create_u32("cur", 0400, ent->dir,
616 					       &ent->cur);
617 		if (!ent->fcur)
618 			return -ENOMEM;
619 
620 		ent->fmiss = debugfs_create_u32("miss", 0600, ent->dir,
621 						&ent->miss);
622 		if (!ent->fmiss)
623 			return -ENOMEM;
624 	}
625 
626 	return 0;
627 }
628 
629 static void mlx5_mr_cache_debugfs_cleanup(struct mlx5_ib_dev *dev)
630 {
631 	if (!mlx5_debugfs_root)
632 		return;
633 
634 	debugfs_remove_recursive(dev->cache.root);
635 }
636 
637 static void delay_time_func(unsigned long ctx)
638 {
639 	struct mlx5_ib_dev *dev = (struct mlx5_ib_dev *)ctx;
640 
641 	dev->fill_delay = 0;
642 }
643 
644 int mlx5_mr_cache_init(struct mlx5_ib_dev *dev)
645 {
646 	struct mlx5_mr_cache *cache = &dev->cache;
647 	struct mlx5_cache_ent *ent;
648 	int err;
649 	int i;
650 
651 	mutex_init(&dev->slow_path_mutex);
652 	cache->wq = alloc_ordered_workqueue("mkey_cache", WQ_MEM_RECLAIM);
653 	if (!cache->wq) {
654 		mlx5_ib_warn(dev, "failed to create work queue\n");
655 		return -ENOMEM;
656 	}
657 
658 	setup_timer(&dev->delay_timer, delay_time_func, (unsigned long)dev);
659 	for (i = 0; i < MAX_MR_CACHE_ENTRIES; i++) {
660 		ent = &cache->ent[i];
661 		INIT_LIST_HEAD(&ent->head);
662 		spin_lock_init(&ent->lock);
663 		ent->order = i + 2;
664 		ent->dev = dev;
665 		ent->limit = 0;
666 
667 		init_completion(&ent->compl);
668 		INIT_WORK(&ent->work, cache_work_func);
669 		INIT_DELAYED_WORK(&ent->dwork, delayed_cache_work_func);
670 		queue_work(cache->wq, &ent->work);
671 
672 		if (i > MAX_UMR_CACHE_ENTRY) {
673 			mlx5_odp_init_mr_cache_entry(ent);
674 			continue;
675 		}
676 
677 		if (!use_umr(dev, ent->order))
678 			continue;
679 
680 		ent->page = PAGE_SHIFT;
681 		ent->xlt = (1 << ent->order) * sizeof(struct mlx5_mtt) /
682 			   MLX5_IB_UMR_OCTOWORD;
683 		ent->access_mode = MLX5_MKC_ACCESS_MODE_MTT;
684 		if ((dev->mdev->profile->mask & MLX5_PROF_MASK_MR_CACHE) &&
685 		    mlx5_core_is_pf(dev->mdev))
686 			ent->limit = dev->mdev->profile->mr_cache[i].limit;
687 		else
688 			ent->limit = 0;
689 	}
690 
691 	err = mlx5_mr_cache_debugfs_init(dev);
692 	if (err)
693 		mlx5_ib_warn(dev, "cache debugfs failure\n");
694 
695 	return 0;
696 }
697 
698 static void wait_for_async_commands(struct mlx5_ib_dev *dev)
699 {
700 	struct mlx5_mr_cache *cache = &dev->cache;
701 	struct mlx5_cache_ent *ent;
702 	int total = 0;
703 	int i;
704 	int j;
705 
706 	for (i = 0; i < MAX_MR_CACHE_ENTRIES; i++) {
707 		ent = &cache->ent[i];
708 		for (j = 0 ; j < 1000; j++) {
709 			if (!ent->pending)
710 				break;
711 			msleep(50);
712 		}
713 	}
714 	for (i = 0; i < MAX_MR_CACHE_ENTRIES; i++) {
715 		ent = &cache->ent[i];
716 		total += ent->pending;
717 	}
718 
719 	if (total)
720 		mlx5_ib_warn(dev, "aborted while there are %d pending mr requests\n", total);
721 	else
722 		mlx5_ib_warn(dev, "done with all pending requests\n");
723 }
724 
725 int mlx5_mr_cache_cleanup(struct mlx5_ib_dev *dev)
726 {
727 	int i;
728 
729 	dev->cache.stopped = 1;
730 	flush_workqueue(dev->cache.wq);
731 
732 	mlx5_mr_cache_debugfs_cleanup(dev);
733 
734 	for (i = 0; i < MAX_MR_CACHE_ENTRIES; i++)
735 		clean_keys(dev, i);
736 
737 	destroy_workqueue(dev->cache.wq);
738 	wait_for_async_commands(dev);
739 	del_timer_sync(&dev->delay_timer);
740 
741 	return 0;
742 }
743 
744 struct ib_mr *mlx5_ib_get_dma_mr(struct ib_pd *pd, int acc)
745 {
746 	struct mlx5_ib_dev *dev = to_mdev(pd->device);
747 	int inlen = MLX5_ST_SZ_BYTES(create_mkey_in);
748 	struct mlx5_core_dev *mdev = dev->mdev;
749 	struct mlx5_ib_mr *mr;
750 	void *mkc;
751 	u32 *in;
752 	int err;
753 
754 	mr = kzalloc(sizeof(*mr), GFP_KERNEL);
755 	if (!mr)
756 		return ERR_PTR(-ENOMEM);
757 
758 	in = kzalloc(inlen, GFP_KERNEL);
759 	if (!in) {
760 		err = -ENOMEM;
761 		goto err_free;
762 	}
763 
764 	mkc = MLX5_ADDR_OF(create_mkey_in, in, memory_key_mkey_entry);
765 
766 	MLX5_SET(mkc, mkc, access_mode, MLX5_MKC_ACCESS_MODE_PA);
767 	MLX5_SET(mkc, mkc, a, !!(acc & IB_ACCESS_REMOTE_ATOMIC));
768 	MLX5_SET(mkc, mkc, rw, !!(acc & IB_ACCESS_REMOTE_WRITE));
769 	MLX5_SET(mkc, mkc, rr, !!(acc & IB_ACCESS_REMOTE_READ));
770 	MLX5_SET(mkc, mkc, lw, !!(acc & IB_ACCESS_LOCAL_WRITE));
771 	MLX5_SET(mkc, mkc, lr, 1);
772 
773 	MLX5_SET(mkc, mkc, length64, 1);
774 	MLX5_SET(mkc, mkc, pd, to_mpd(pd)->pdn);
775 	MLX5_SET(mkc, mkc, qpn, 0xffffff);
776 	MLX5_SET64(mkc, mkc, start_addr, 0);
777 
778 	err = mlx5_core_create_mkey(mdev, &mr->mmkey, in, inlen);
779 	if (err)
780 		goto err_in;
781 
782 	kfree(in);
783 	mr->mmkey.type = MLX5_MKEY_MR;
784 	mr->ibmr.lkey = mr->mmkey.key;
785 	mr->ibmr.rkey = mr->mmkey.key;
786 	mr->umem = NULL;
787 
788 	return &mr->ibmr;
789 
790 err_in:
791 	kfree(in);
792 
793 err_free:
794 	kfree(mr);
795 
796 	return ERR_PTR(err);
797 }
798 
799 static int get_octo_len(u64 addr, u64 len, int page_size)
800 {
801 	u64 offset;
802 	int npages;
803 
804 	offset = addr & (page_size - 1);
805 	npages = ALIGN(len + offset, page_size) >> ilog2(page_size);
806 	return (npages + 1) / 2;
807 }
808 
809 static int use_umr(struct mlx5_ib_dev *dev, int order)
810 {
811 	if (MLX5_CAP_GEN(dev->mdev, umr_extended_translation_offset))
812 		return order <= MAX_UMR_CACHE_ENTRY + 2;
813 	return order <= MLX5_MAX_UMR_SHIFT;
814 }
815 
816 static int mr_umem_get(struct ib_pd *pd, u64 start, u64 length,
817 		       int access_flags, struct ib_umem **umem,
818 		       int *npages, int *page_shift, int *ncont,
819 		       int *order)
820 {
821 	struct mlx5_ib_dev *dev = to_mdev(pd->device);
822 	int err;
823 
824 	*umem = ib_umem_get(pd->uobject->context, start, length,
825 			    access_flags, 0);
826 	err = PTR_ERR_OR_ZERO(*umem);
827 	if (err < 0) {
828 		mlx5_ib_err(dev, "umem get failed (%ld)\n", PTR_ERR(umem));
829 		return err;
830 	}
831 
832 	mlx5_ib_cont_pages(*umem, start, MLX5_MKEY_PAGE_SHIFT_MASK, npages,
833 			   page_shift, ncont, order);
834 	if (!*npages) {
835 		mlx5_ib_warn(dev, "avoid zero region\n");
836 		ib_umem_release(*umem);
837 		return -EINVAL;
838 	}
839 
840 	mlx5_ib_dbg(dev, "npages %d, ncont %d, order %d, page_shift %d\n",
841 		    *npages, *ncont, *order, *page_shift);
842 
843 	return 0;
844 }
845 
846 static void mlx5_ib_umr_done(struct ib_cq *cq, struct ib_wc *wc)
847 {
848 	struct mlx5_ib_umr_context *context =
849 		container_of(wc->wr_cqe, struct mlx5_ib_umr_context, cqe);
850 
851 	context->status = wc->status;
852 	complete(&context->done);
853 }
854 
855 static inline void mlx5_ib_init_umr_context(struct mlx5_ib_umr_context *context)
856 {
857 	context->cqe.done = mlx5_ib_umr_done;
858 	context->status = -1;
859 	init_completion(&context->done);
860 }
861 
862 static int mlx5_ib_post_send_wait(struct mlx5_ib_dev *dev,
863 				  struct mlx5_umr_wr *umrwr)
864 {
865 	struct umr_common *umrc = &dev->umrc;
866 	struct ib_send_wr *bad;
867 	int err;
868 	struct mlx5_ib_umr_context umr_context;
869 
870 	mlx5_ib_init_umr_context(&umr_context);
871 	umrwr->wr.wr_cqe = &umr_context.cqe;
872 
873 	down(&umrc->sem);
874 	err = ib_post_send(umrc->qp, &umrwr->wr, &bad);
875 	if (err) {
876 		mlx5_ib_warn(dev, "UMR post send failed, err %d\n", err);
877 	} else {
878 		wait_for_completion(&umr_context.done);
879 		if (umr_context.status != IB_WC_SUCCESS) {
880 			mlx5_ib_warn(dev, "reg umr failed (%u)\n",
881 				     umr_context.status);
882 			err = -EFAULT;
883 		}
884 	}
885 	up(&umrc->sem);
886 	return err;
887 }
888 
889 static struct mlx5_ib_mr *reg_umr(struct ib_pd *pd, struct ib_umem *umem,
890 				  u64 virt_addr, u64 len, int npages,
891 				  int page_shift, int order, int access_flags)
892 {
893 	struct mlx5_ib_dev *dev = to_mdev(pd->device);
894 	struct mlx5_ib_mr *mr;
895 	int err = 0;
896 	int i;
897 
898 	for (i = 0; i < 1; i++) {
899 		mr = alloc_cached_mr(dev, order);
900 		if (mr)
901 			break;
902 
903 		err = add_keys(dev, order2idx(dev, order), 1);
904 		if (err && err != -EAGAIN) {
905 			mlx5_ib_warn(dev, "add_keys failed, err %d\n", err);
906 			break;
907 		}
908 	}
909 
910 	if (!mr)
911 		return ERR_PTR(-EAGAIN);
912 
913 	mr->ibmr.pd = pd;
914 	mr->umem = umem;
915 	mr->access_flags = access_flags;
916 	mr->desc_size = sizeof(struct mlx5_mtt);
917 	mr->mmkey.iova = virt_addr;
918 	mr->mmkey.size = len;
919 	mr->mmkey.pd = to_mpd(pd)->pdn;
920 
921 	err = mlx5_ib_update_xlt(mr, 0, npages, page_shift,
922 				 MLX5_IB_UPD_XLT_ENABLE);
923 
924 	if (err) {
925 		mlx5_mr_cache_free(dev, mr);
926 		return ERR_PTR(err);
927 	}
928 
929 	mr->live = 1;
930 
931 	return mr;
932 }
933 
934 static inline int populate_xlt(struct mlx5_ib_mr *mr, int idx, int npages,
935 			       void *xlt, int page_shift, size_t size,
936 			       int flags)
937 {
938 	struct mlx5_ib_dev *dev = mr->dev;
939 	struct ib_umem *umem = mr->umem;
940 	if (flags & MLX5_IB_UPD_XLT_INDIRECT) {
941 		mlx5_odp_populate_klm(xlt, idx, npages, mr, flags);
942 		return npages;
943 	}
944 
945 	npages = min_t(size_t, npages, ib_umem_num_pages(umem) - idx);
946 
947 	if (!(flags & MLX5_IB_UPD_XLT_ZAP)) {
948 		__mlx5_ib_populate_pas(dev, umem, page_shift,
949 				       idx, npages, xlt,
950 				       MLX5_IB_MTT_PRESENT);
951 		/* Clear padding after the pages
952 		 * brought from the umem.
953 		 */
954 		memset(xlt + (npages * sizeof(struct mlx5_mtt)), 0,
955 		       size - npages * sizeof(struct mlx5_mtt));
956 	}
957 
958 	return npages;
959 }
960 
961 #define MLX5_MAX_UMR_CHUNK ((1 << (MLX5_MAX_UMR_SHIFT + 4)) - \
962 			    MLX5_UMR_MTT_ALIGNMENT)
963 #define MLX5_SPARE_UMR_CHUNK 0x10000
964 
965 int mlx5_ib_update_xlt(struct mlx5_ib_mr *mr, u64 idx, int npages,
966 		       int page_shift, int flags)
967 {
968 	struct mlx5_ib_dev *dev = mr->dev;
969 	struct device *ddev = dev->ib_dev.dev.parent;
970 	struct mlx5_ib_ucontext *uctx = NULL;
971 	int size;
972 	void *xlt;
973 	dma_addr_t dma;
974 	struct mlx5_umr_wr wr;
975 	struct ib_sge sg;
976 	int err = 0;
977 	int desc_size = (flags & MLX5_IB_UPD_XLT_INDIRECT)
978 			       ? sizeof(struct mlx5_klm)
979 			       : sizeof(struct mlx5_mtt);
980 	const int page_align = MLX5_UMR_MTT_ALIGNMENT / desc_size;
981 	const int page_mask = page_align - 1;
982 	size_t pages_mapped = 0;
983 	size_t pages_to_map = 0;
984 	size_t pages_iter = 0;
985 	gfp_t gfp;
986 
987 	/* UMR copies MTTs in units of MLX5_UMR_MTT_ALIGNMENT bytes,
988 	 * so we need to align the offset and length accordingly
989 	 */
990 	if (idx & page_mask) {
991 		npages += idx & page_mask;
992 		idx &= ~page_mask;
993 	}
994 
995 	gfp = flags & MLX5_IB_UPD_XLT_ATOMIC ? GFP_ATOMIC : GFP_KERNEL;
996 	gfp |= __GFP_ZERO | __GFP_NOWARN;
997 
998 	pages_to_map = ALIGN(npages, page_align);
999 	size = desc_size * pages_to_map;
1000 	size = min_t(int, size, MLX5_MAX_UMR_CHUNK);
1001 
1002 	xlt = (void *)__get_free_pages(gfp, get_order(size));
1003 	if (!xlt && size > MLX5_SPARE_UMR_CHUNK) {
1004 		mlx5_ib_dbg(dev, "Failed to allocate %d bytes of order %d. fallback to spare UMR allocation od %d bytes\n",
1005 			    size, get_order(size), MLX5_SPARE_UMR_CHUNK);
1006 
1007 		size = MLX5_SPARE_UMR_CHUNK;
1008 		xlt = (void *)__get_free_pages(gfp, get_order(size));
1009 	}
1010 
1011 	if (!xlt) {
1012 		uctx = to_mucontext(mr->ibmr.pd->uobject->context);
1013 		mlx5_ib_warn(dev, "Using XLT emergency buffer\n");
1014 		size = PAGE_SIZE;
1015 		xlt = (void *)uctx->upd_xlt_page;
1016 		mutex_lock(&uctx->upd_xlt_page_mutex);
1017 		memset(xlt, 0, size);
1018 	}
1019 	pages_iter = size / desc_size;
1020 	dma = dma_map_single(ddev, xlt, size, DMA_TO_DEVICE);
1021 	if (dma_mapping_error(ddev, dma)) {
1022 		mlx5_ib_err(dev, "unable to map DMA during XLT update.\n");
1023 		err = -ENOMEM;
1024 		goto free_xlt;
1025 	}
1026 
1027 	sg.addr = dma;
1028 	sg.lkey = dev->umrc.pd->local_dma_lkey;
1029 
1030 	memset(&wr, 0, sizeof(wr));
1031 	wr.wr.send_flags = MLX5_IB_SEND_UMR_UPDATE_XLT;
1032 	if (!(flags & MLX5_IB_UPD_XLT_ENABLE))
1033 		wr.wr.send_flags |= MLX5_IB_SEND_UMR_FAIL_IF_FREE;
1034 	wr.wr.sg_list = &sg;
1035 	wr.wr.num_sge = 1;
1036 	wr.wr.opcode = MLX5_IB_WR_UMR;
1037 
1038 	wr.pd = mr->ibmr.pd;
1039 	wr.mkey = mr->mmkey.key;
1040 	wr.length = mr->mmkey.size;
1041 	wr.virt_addr = mr->mmkey.iova;
1042 	wr.access_flags = mr->access_flags;
1043 	wr.page_shift = page_shift;
1044 
1045 	for (pages_mapped = 0;
1046 	     pages_mapped < pages_to_map && !err;
1047 	     pages_mapped += pages_iter, idx += pages_iter) {
1048 		npages = min_t(int, pages_iter, pages_to_map - pages_mapped);
1049 		dma_sync_single_for_cpu(ddev, dma, size, DMA_TO_DEVICE);
1050 		npages = populate_xlt(mr, idx, npages, xlt,
1051 				      page_shift, size, flags);
1052 
1053 		dma_sync_single_for_device(ddev, dma, size, DMA_TO_DEVICE);
1054 
1055 		sg.length = ALIGN(npages * desc_size,
1056 				  MLX5_UMR_MTT_ALIGNMENT);
1057 
1058 		if (pages_mapped + pages_iter >= pages_to_map) {
1059 			if (flags & MLX5_IB_UPD_XLT_ENABLE)
1060 				wr.wr.send_flags |=
1061 					MLX5_IB_SEND_UMR_ENABLE_MR |
1062 					MLX5_IB_SEND_UMR_UPDATE_PD_ACCESS |
1063 					MLX5_IB_SEND_UMR_UPDATE_TRANSLATION;
1064 			if (flags & MLX5_IB_UPD_XLT_PD ||
1065 			    flags & MLX5_IB_UPD_XLT_ACCESS)
1066 				wr.wr.send_flags |=
1067 					MLX5_IB_SEND_UMR_UPDATE_PD_ACCESS;
1068 			if (flags & MLX5_IB_UPD_XLT_ADDR)
1069 				wr.wr.send_flags |=
1070 					MLX5_IB_SEND_UMR_UPDATE_TRANSLATION;
1071 		}
1072 
1073 		wr.offset = idx * desc_size;
1074 		wr.xlt_size = sg.length;
1075 
1076 		err = mlx5_ib_post_send_wait(dev, &wr);
1077 	}
1078 	dma_unmap_single(ddev, dma, size, DMA_TO_DEVICE);
1079 
1080 free_xlt:
1081 	if (uctx)
1082 		mutex_unlock(&uctx->upd_xlt_page_mutex);
1083 	else
1084 		free_pages((unsigned long)xlt, get_order(size));
1085 
1086 	return err;
1087 }
1088 
1089 /*
1090  * If ibmr is NULL it will be allocated by reg_create.
1091  * Else, the given ibmr will be used.
1092  */
1093 static struct mlx5_ib_mr *reg_create(struct ib_mr *ibmr, struct ib_pd *pd,
1094 				     u64 virt_addr, u64 length,
1095 				     struct ib_umem *umem, int npages,
1096 				     int page_shift, int access_flags)
1097 {
1098 	struct mlx5_ib_dev *dev = to_mdev(pd->device);
1099 	struct mlx5_ib_mr *mr;
1100 	__be64 *pas;
1101 	void *mkc;
1102 	int inlen;
1103 	u32 *in;
1104 	int err;
1105 	bool pg_cap = !!(MLX5_CAP_GEN(dev->mdev, pg));
1106 
1107 	mr = ibmr ? to_mmr(ibmr) : kzalloc(sizeof(*mr), GFP_KERNEL);
1108 	if (!mr)
1109 		return ERR_PTR(-ENOMEM);
1110 
1111 	inlen = MLX5_ST_SZ_BYTES(create_mkey_in) +
1112 		sizeof(*pas) * ((npages + 1) / 2) * 2;
1113 	in = mlx5_vzalloc(inlen);
1114 	if (!in) {
1115 		err = -ENOMEM;
1116 		goto err_1;
1117 	}
1118 	pas = (__be64 *)MLX5_ADDR_OF(create_mkey_in, in, klm_pas_mtt);
1119 	if (!(access_flags & IB_ACCESS_ON_DEMAND))
1120 		mlx5_ib_populate_pas(dev, umem, page_shift, pas,
1121 				     pg_cap ? MLX5_IB_MTT_PRESENT : 0);
1122 
1123 	/* The pg_access bit allows setting the access flags
1124 	 * in the page list submitted with the command. */
1125 	MLX5_SET(create_mkey_in, in, pg_access, !!(pg_cap));
1126 
1127 	mkc = MLX5_ADDR_OF(create_mkey_in, in, memory_key_mkey_entry);
1128 	MLX5_SET(mkc, mkc, access_mode, MLX5_MKC_ACCESS_MODE_MTT);
1129 	MLX5_SET(mkc, mkc, a, !!(access_flags & IB_ACCESS_REMOTE_ATOMIC));
1130 	MLX5_SET(mkc, mkc, rw, !!(access_flags & IB_ACCESS_REMOTE_WRITE));
1131 	MLX5_SET(mkc, mkc, rr, !!(access_flags & IB_ACCESS_REMOTE_READ));
1132 	MLX5_SET(mkc, mkc, lw, !!(access_flags & IB_ACCESS_LOCAL_WRITE));
1133 	MLX5_SET(mkc, mkc, lr, 1);
1134 
1135 	MLX5_SET64(mkc, mkc, start_addr, virt_addr);
1136 	MLX5_SET64(mkc, mkc, len, length);
1137 	MLX5_SET(mkc, mkc, pd, to_mpd(pd)->pdn);
1138 	MLX5_SET(mkc, mkc, bsf_octword_size, 0);
1139 	MLX5_SET(mkc, mkc, translations_octword_size,
1140 		 get_octo_len(virt_addr, length, 1 << page_shift));
1141 	MLX5_SET(mkc, mkc, log_page_size, page_shift);
1142 	MLX5_SET(mkc, mkc, qpn, 0xffffff);
1143 	MLX5_SET(create_mkey_in, in, translations_octword_actual_size,
1144 		 get_octo_len(virt_addr, length, 1 << page_shift));
1145 
1146 	err = mlx5_core_create_mkey(dev->mdev, &mr->mmkey, in, inlen);
1147 	if (err) {
1148 		mlx5_ib_warn(dev, "create mkey failed\n");
1149 		goto err_2;
1150 	}
1151 	mr->mmkey.type = MLX5_MKEY_MR;
1152 	mr->desc_size = sizeof(struct mlx5_mtt);
1153 	mr->umem = umem;
1154 	mr->dev = dev;
1155 	mr->live = 1;
1156 	kvfree(in);
1157 
1158 	mlx5_ib_dbg(dev, "mkey = 0x%x\n", mr->mmkey.key);
1159 
1160 	return mr;
1161 
1162 err_2:
1163 	kvfree(in);
1164 
1165 err_1:
1166 	if (!ibmr)
1167 		kfree(mr);
1168 
1169 	return ERR_PTR(err);
1170 }
1171 
1172 static void set_mr_fileds(struct mlx5_ib_dev *dev, struct mlx5_ib_mr *mr,
1173 			  int npages, u64 length, int access_flags)
1174 {
1175 	mr->npages = npages;
1176 	atomic_add(npages, &dev->mdev->priv.reg_pages);
1177 	mr->ibmr.lkey = mr->mmkey.key;
1178 	mr->ibmr.rkey = mr->mmkey.key;
1179 	mr->ibmr.length = length;
1180 	mr->access_flags = access_flags;
1181 }
1182 
1183 struct ib_mr *mlx5_ib_reg_user_mr(struct ib_pd *pd, u64 start, u64 length,
1184 				  u64 virt_addr, int access_flags,
1185 				  struct ib_udata *udata)
1186 {
1187 	struct mlx5_ib_dev *dev = to_mdev(pd->device);
1188 	struct mlx5_ib_mr *mr = NULL;
1189 	struct ib_umem *umem;
1190 	int page_shift;
1191 	int npages;
1192 	int ncont;
1193 	int order;
1194 	int err;
1195 
1196 	mlx5_ib_dbg(dev, "start 0x%llx, virt_addr 0x%llx, length 0x%llx, access_flags 0x%x\n",
1197 		    start, virt_addr, length, access_flags);
1198 
1199 #ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
1200 	if (!start && length == U64_MAX) {
1201 		if (!(access_flags & IB_ACCESS_ON_DEMAND) ||
1202 		    !(dev->odp_caps.general_caps & IB_ODP_SUPPORT_IMPLICIT))
1203 			return ERR_PTR(-EINVAL);
1204 
1205 		mr = mlx5_ib_alloc_implicit_mr(to_mpd(pd), access_flags);
1206 		return &mr->ibmr;
1207 	}
1208 #endif
1209 
1210 	err = mr_umem_get(pd, start, length, access_flags, &umem, &npages,
1211 			   &page_shift, &ncont, &order);
1212 
1213         if (err < 0)
1214 		return ERR_PTR(err);
1215 
1216 	if (use_umr(dev, order)) {
1217 		mr = reg_umr(pd, umem, virt_addr, length, ncont, page_shift,
1218 			     order, access_flags);
1219 		if (PTR_ERR(mr) == -EAGAIN) {
1220 			mlx5_ib_dbg(dev, "cache empty for order %d", order);
1221 			mr = NULL;
1222 		}
1223 	} else if (access_flags & IB_ACCESS_ON_DEMAND &&
1224 		   !MLX5_CAP_GEN(dev->mdev, umr_extended_translation_offset)) {
1225 		err = -EINVAL;
1226 		pr_err("Got MR registration for ODP MR > 512MB, not supported for Connect-IB");
1227 		goto error;
1228 	}
1229 
1230 	if (!mr) {
1231 		mutex_lock(&dev->slow_path_mutex);
1232 		mr = reg_create(NULL, pd, virt_addr, length, umem, ncont,
1233 				page_shift, access_flags);
1234 		mutex_unlock(&dev->slow_path_mutex);
1235 	}
1236 
1237 	if (IS_ERR(mr)) {
1238 		err = PTR_ERR(mr);
1239 		goto error;
1240 	}
1241 
1242 	mlx5_ib_dbg(dev, "mkey 0x%x\n", mr->mmkey.key);
1243 
1244 	mr->umem = umem;
1245 	set_mr_fileds(dev, mr, npages, length, access_flags);
1246 
1247 #ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
1248 	update_odp_mr(mr);
1249 #endif
1250 
1251 	return &mr->ibmr;
1252 
1253 error:
1254 	ib_umem_release(umem);
1255 	return ERR_PTR(err);
1256 }
1257 
1258 static int unreg_umr(struct mlx5_ib_dev *dev, struct mlx5_ib_mr *mr)
1259 {
1260 	struct mlx5_core_dev *mdev = dev->mdev;
1261 	struct mlx5_umr_wr umrwr = {};
1262 
1263 	if (mdev->state == MLX5_DEVICE_STATE_INTERNAL_ERROR)
1264 		return 0;
1265 
1266 	umrwr.wr.send_flags = MLX5_IB_SEND_UMR_DISABLE_MR |
1267 			      MLX5_IB_SEND_UMR_FAIL_IF_FREE;
1268 	umrwr.wr.opcode = MLX5_IB_WR_UMR;
1269 	umrwr.mkey = mr->mmkey.key;
1270 
1271 	return mlx5_ib_post_send_wait(dev, &umrwr);
1272 }
1273 
1274 static int rereg_umr(struct ib_pd *pd, struct mlx5_ib_mr *mr,
1275 		     int access_flags, int flags)
1276 {
1277 	struct mlx5_ib_dev *dev = to_mdev(pd->device);
1278 	struct mlx5_umr_wr umrwr = {};
1279 	int err;
1280 
1281 	umrwr.wr.send_flags = MLX5_IB_SEND_UMR_FAIL_IF_FREE;
1282 
1283 	umrwr.wr.opcode = MLX5_IB_WR_UMR;
1284 	umrwr.mkey = mr->mmkey.key;
1285 
1286 	if (flags & IB_MR_REREG_PD || flags & IB_MR_REREG_ACCESS) {
1287 		umrwr.pd = pd;
1288 		umrwr.access_flags = access_flags;
1289 		umrwr.wr.send_flags |= MLX5_IB_SEND_UMR_UPDATE_PD_ACCESS;
1290 	}
1291 
1292 	err = mlx5_ib_post_send_wait(dev, &umrwr);
1293 
1294 	return err;
1295 }
1296 
1297 int mlx5_ib_rereg_user_mr(struct ib_mr *ib_mr, int flags, u64 start,
1298 			  u64 length, u64 virt_addr, int new_access_flags,
1299 			  struct ib_pd *new_pd, struct ib_udata *udata)
1300 {
1301 	struct mlx5_ib_dev *dev = to_mdev(ib_mr->device);
1302 	struct mlx5_ib_mr *mr = to_mmr(ib_mr);
1303 	struct ib_pd *pd = (flags & IB_MR_REREG_PD) ? new_pd : ib_mr->pd;
1304 	int access_flags = flags & IB_MR_REREG_ACCESS ?
1305 			    new_access_flags :
1306 			    mr->access_flags;
1307 	u64 addr = (flags & IB_MR_REREG_TRANS) ? virt_addr : mr->umem->address;
1308 	u64 len = (flags & IB_MR_REREG_TRANS) ? length : mr->umem->length;
1309 	int page_shift = 0;
1310 	int upd_flags = 0;
1311 	int npages = 0;
1312 	int ncont = 0;
1313 	int order = 0;
1314 	int err;
1315 
1316 	mlx5_ib_dbg(dev, "start 0x%llx, virt_addr 0x%llx, length 0x%llx, access_flags 0x%x\n",
1317 		    start, virt_addr, length, access_flags);
1318 
1319 	atomic_sub(mr->npages, &dev->mdev->priv.reg_pages);
1320 
1321 	if (flags != IB_MR_REREG_PD) {
1322 		/*
1323 		 * Replace umem. This needs to be done whether or not UMR is
1324 		 * used.
1325 		 */
1326 		flags |= IB_MR_REREG_TRANS;
1327 		ib_umem_release(mr->umem);
1328 		err = mr_umem_get(pd, addr, len, access_flags, &mr->umem,
1329 				  &npages, &page_shift, &ncont, &order);
1330 		if (err < 0) {
1331 			clean_mr(mr);
1332 			return err;
1333 		}
1334 	}
1335 
1336 	if (flags & IB_MR_REREG_TRANS && !use_umr_mtt_update(mr, addr, len)) {
1337 		/*
1338 		 * UMR can't be used - MKey needs to be replaced.
1339 		 */
1340 		if (mr->umred) {
1341 			err = unreg_umr(dev, mr);
1342 			if (err)
1343 				mlx5_ib_warn(dev, "Failed to unregister MR\n");
1344 		} else {
1345 			err = destroy_mkey(dev, mr);
1346 			if (err)
1347 				mlx5_ib_warn(dev, "Failed to destroy MKey\n");
1348 		}
1349 		if (err)
1350 			return err;
1351 
1352 		mr = reg_create(ib_mr, pd, addr, len, mr->umem, ncont,
1353 				page_shift, access_flags);
1354 
1355 		if (IS_ERR(mr))
1356 			return PTR_ERR(mr);
1357 
1358 		mr->umred = 0;
1359 	} else {
1360 		/*
1361 		 * Send a UMR WQE
1362 		 */
1363 		mr->ibmr.pd = pd;
1364 		mr->access_flags = access_flags;
1365 		mr->mmkey.iova = addr;
1366 		mr->mmkey.size = len;
1367 		mr->mmkey.pd = to_mpd(pd)->pdn;
1368 
1369 		if (flags & IB_MR_REREG_TRANS) {
1370 			upd_flags = MLX5_IB_UPD_XLT_ADDR;
1371 			if (flags & IB_MR_REREG_PD)
1372 				upd_flags |= MLX5_IB_UPD_XLT_PD;
1373 			if (flags & IB_MR_REREG_ACCESS)
1374 				upd_flags |= MLX5_IB_UPD_XLT_ACCESS;
1375 			err = mlx5_ib_update_xlt(mr, 0, npages, page_shift,
1376 						 upd_flags);
1377 		} else {
1378 			err = rereg_umr(pd, mr, access_flags, flags);
1379 		}
1380 
1381 		if (err) {
1382 			mlx5_ib_warn(dev, "Failed to rereg UMR\n");
1383 			ib_umem_release(mr->umem);
1384 			clean_mr(mr);
1385 			return err;
1386 		}
1387 	}
1388 
1389 	set_mr_fileds(dev, mr, npages, len, access_flags);
1390 
1391 #ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
1392 	update_odp_mr(mr);
1393 #endif
1394 	return 0;
1395 }
1396 
1397 static int
1398 mlx5_alloc_priv_descs(struct ib_device *device,
1399 		      struct mlx5_ib_mr *mr,
1400 		      int ndescs,
1401 		      int desc_size)
1402 {
1403 	int size = ndescs * desc_size;
1404 	int add_size;
1405 	int ret;
1406 
1407 	add_size = max_t(int, MLX5_UMR_ALIGN - ARCH_KMALLOC_MINALIGN, 0);
1408 
1409 	mr->descs_alloc = kzalloc(size + add_size, GFP_KERNEL);
1410 	if (!mr->descs_alloc)
1411 		return -ENOMEM;
1412 
1413 	mr->descs = PTR_ALIGN(mr->descs_alloc, MLX5_UMR_ALIGN);
1414 
1415 	mr->desc_map = dma_map_single(device->dev.parent, mr->descs,
1416 				      size, DMA_TO_DEVICE);
1417 	if (dma_mapping_error(device->dev.parent, mr->desc_map)) {
1418 		ret = -ENOMEM;
1419 		goto err;
1420 	}
1421 
1422 	return 0;
1423 err:
1424 	kfree(mr->descs_alloc);
1425 
1426 	return ret;
1427 }
1428 
1429 static void
1430 mlx5_free_priv_descs(struct mlx5_ib_mr *mr)
1431 {
1432 	if (mr->descs) {
1433 		struct ib_device *device = mr->ibmr.device;
1434 		int size = mr->max_descs * mr->desc_size;
1435 
1436 		dma_unmap_single(device->dev.parent, mr->desc_map,
1437 				 size, DMA_TO_DEVICE);
1438 		kfree(mr->descs_alloc);
1439 		mr->descs = NULL;
1440 	}
1441 }
1442 
1443 static int clean_mr(struct mlx5_ib_mr *mr)
1444 {
1445 	struct mlx5_ib_dev *dev = to_mdev(mr->ibmr.device);
1446 	int umred = mr->umred;
1447 	int err;
1448 
1449 	if (mr->sig) {
1450 		if (mlx5_core_destroy_psv(dev->mdev,
1451 					  mr->sig->psv_memory.psv_idx))
1452 			mlx5_ib_warn(dev, "failed to destroy mem psv %d\n",
1453 				     mr->sig->psv_memory.psv_idx);
1454 		if (mlx5_core_destroy_psv(dev->mdev,
1455 					  mr->sig->psv_wire.psv_idx))
1456 			mlx5_ib_warn(dev, "failed to destroy wire psv %d\n",
1457 				     mr->sig->psv_wire.psv_idx);
1458 		kfree(mr->sig);
1459 		mr->sig = NULL;
1460 	}
1461 
1462 	mlx5_free_priv_descs(mr);
1463 
1464 	if (!umred) {
1465 		err = destroy_mkey(dev, mr);
1466 		if (err) {
1467 			mlx5_ib_warn(dev, "failed to destroy mkey 0x%x (%d)\n",
1468 				     mr->mmkey.key, err);
1469 			return err;
1470 		}
1471 	} else {
1472 		mlx5_mr_cache_free(dev, mr);
1473 	}
1474 
1475 	if (!umred)
1476 		kfree(mr);
1477 
1478 	return 0;
1479 }
1480 
1481 int mlx5_ib_dereg_mr(struct ib_mr *ibmr)
1482 {
1483 	struct mlx5_ib_dev *dev = to_mdev(ibmr->device);
1484 	struct mlx5_ib_mr *mr = to_mmr(ibmr);
1485 	int npages = mr->npages;
1486 	struct ib_umem *umem = mr->umem;
1487 
1488 #ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
1489 	if (umem && umem->odp_data) {
1490 		/* Prevent new page faults from succeeding */
1491 		mr->live = 0;
1492 		/* Wait for all running page-fault handlers to finish. */
1493 		synchronize_srcu(&dev->mr_srcu);
1494 		/* Destroy all page mappings */
1495 		if (umem->odp_data->page_list)
1496 			mlx5_ib_invalidate_range(umem, ib_umem_start(umem),
1497 						 ib_umem_end(umem));
1498 		else
1499 			mlx5_ib_free_implicit_mr(mr);
1500 		/*
1501 		 * We kill the umem before the MR for ODP,
1502 		 * so that there will not be any invalidations in
1503 		 * flight, looking at the *mr struct.
1504 		 */
1505 		ib_umem_release(umem);
1506 		atomic_sub(npages, &dev->mdev->priv.reg_pages);
1507 
1508 		/* Avoid double-freeing the umem. */
1509 		umem = NULL;
1510 	}
1511 #endif
1512 
1513 	clean_mr(mr);
1514 
1515 	if (umem) {
1516 		ib_umem_release(umem);
1517 		atomic_sub(npages, &dev->mdev->priv.reg_pages);
1518 	}
1519 
1520 	return 0;
1521 }
1522 
1523 struct ib_mr *mlx5_ib_alloc_mr(struct ib_pd *pd,
1524 			       enum ib_mr_type mr_type,
1525 			       u32 max_num_sg)
1526 {
1527 	struct mlx5_ib_dev *dev = to_mdev(pd->device);
1528 	int inlen = MLX5_ST_SZ_BYTES(create_mkey_in);
1529 	int ndescs = ALIGN(max_num_sg, 4);
1530 	struct mlx5_ib_mr *mr;
1531 	void *mkc;
1532 	u32 *in;
1533 	int err;
1534 
1535 	mr = kzalloc(sizeof(*mr), GFP_KERNEL);
1536 	if (!mr)
1537 		return ERR_PTR(-ENOMEM);
1538 
1539 	in = kzalloc(inlen, GFP_KERNEL);
1540 	if (!in) {
1541 		err = -ENOMEM;
1542 		goto err_free;
1543 	}
1544 
1545 	mkc = MLX5_ADDR_OF(create_mkey_in, in, memory_key_mkey_entry);
1546 	MLX5_SET(mkc, mkc, free, 1);
1547 	MLX5_SET(mkc, mkc, translations_octword_size, ndescs);
1548 	MLX5_SET(mkc, mkc, qpn, 0xffffff);
1549 	MLX5_SET(mkc, mkc, pd, to_mpd(pd)->pdn);
1550 
1551 	if (mr_type == IB_MR_TYPE_MEM_REG) {
1552 		mr->access_mode = MLX5_MKC_ACCESS_MODE_MTT;
1553 		MLX5_SET(mkc, mkc, log_page_size, PAGE_SHIFT);
1554 		err = mlx5_alloc_priv_descs(pd->device, mr,
1555 					    ndescs, sizeof(struct mlx5_mtt));
1556 		if (err)
1557 			goto err_free_in;
1558 
1559 		mr->desc_size = sizeof(struct mlx5_mtt);
1560 		mr->max_descs = ndescs;
1561 	} else if (mr_type == IB_MR_TYPE_SG_GAPS) {
1562 		mr->access_mode = MLX5_MKC_ACCESS_MODE_KLMS;
1563 
1564 		err = mlx5_alloc_priv_descs(pd->device, mr,
1565 					    ndescs, sizeof(struct mlx5_klm));
1566 		if (err)
1567 			goto err_free_in;
1568 		mr->desc_size = sizeof(struct mlx5_klm);
1569 		mr->max_descs = ndescs;
1570 	} else if (mr_type == IB_MR_TYPE_SIGNATURE) {
1571 		u32 psv_index[2];
1572 
1573 		MLX5_SET(mkc, mkc, bsf_en, 1);
1574 		MLX5_SET(mkc, mkc, bsf_octword_size, MLX5_MKEY_BSF_OCTO_SIZE);
1575 		mr->sig = kzalloc(sizeof(*mr->sig), GFP_KERNEL);
1576 		if (!mr->sig) {
1577 			err = -ENOMEM;
1578 			goto err_free_in;
1579 		}
1580 
1581 		/* create mem & wire PSVs */
1582 		err = mlx5_core_create_psv(dev->mdev, to_mpd(pd)->pdn,
1583 					   2, psv_index);
1584 		if (err)
1585 			goto err_free_sig;
1586 
1587 		mr->access_mode = MLX5_MKC_ACCESS_MODE_KLMS;
1588 		mr->sig->psv_memory.psv_idx = psv_index[0];
1589 		mr->sig->psv_wire.psv_idx = psv_index[1];
1590 
1591 		mr->sig->sig_status_checked = true;
1592 		mr->sig->sig_err_exists = false;
1593 		/* Next UMR, Arm SIGERR */
1594 		++mr->sig->sigerr_count;
1595 	} else {
1596 		mlx5_ib_warn(dev, "Invalid mr type %d\n", mr_type);
1597 		err = -EINVAL;
1598 		goto err_free_in;
1599 	}
1600 
1601 	MLX5_SET(mkc, mkc, access_mode, mr->access_mode);
1602 	MLX5_SET(mkc, mkc, umr_en, 1);
1603 
1604 	err = mlx5_core_create_mkey(dev->mdev, &mr->mmkey, in, inlen);
1605 	if (err)
1606 		goto err_destroy_psv;
1607 
1608 	mr->mmkey.type = MLX5_MKEY_MR;
1609 	mr->ibmr.lkey = mr->mmkey.key;
1610 	mr->ibmr.rkey = mr->mmkey.key;
1611 	mr->umem = NULL;
1612 	kfree(in);
1613 
1614 	return &mr->ibmr;
1615 
1616 err_destroy_psv:
1617 	if (mr->sig) {
1618 		if (mlx5_core_destroy_psv(dev->mdev,
1619 					  mr->sig->psv_memory.psv_idx))
1620 			mlx5_ib_warn(dev, "failed to destroy mem psv %d\n",
1621 				     mr->sig->psv_memory.psv_idx);
1622 		if (mlx5_core_destroy_psv(dev->mdev,
1623 					  mr->sig->psv_wire.psv_idx))
1624 			mlx5_ib_warn(dev, "failed to destroy wire psv %d\n",
1625 				     mr->sig->psv_wire.psv_idx);
1626 	}
1627 	mlx5_free_priv_descs(mr);
1628 err_free_sig:
1629 	kfree(mr->sig);
1630 err_free_in:
1631 	kfree(in);
1632 err_free:
1633 	kfree(mr);
1634 	return ERR_PTR(err);
1635 }
1636 
1637 struct ib_mw *mlx5_ib_alloc_mw(struct ib_pd *pd, enum ib_mw_type type,
1638 			       struct ib_udata *udata)
1639 {
1640 	struct mlx5_ib_dev *dev = to_mdev(pd->device);
1641 	int inlen = MLX5_ST_SZ_BYTES(create_mkey_in);
1642 	struct mlx5_ib_mw *mw = NULL;
1643 	u32 *in = NULL;
1644 	void *mkc;
1645 	int ndescs;
1646 	int err;
1647 	struct mlx5_ib_alloc_mw req = {};
1648 	struct {
1649 		__u32	comp_mask;
1650 		__u32	response_length;
1651 	} resp = {};
1652 
1653 	err = ib_copy_from_udata(&req, udata, min(udata->inlen, sizeof(req)));
1654 	if (err)
1655 		return ERR_PTR(err);
1656 
1657 	if (req.comp_mask || req.reserved1 || req.reserved2)
1658 		return ERR_PTR(-EOPNOTSUPP);
1659 
1660 	if (udata->inlen > sizeof(req) &&
1661 	    !ib_is_udata_cleared(udata, sizeof(req),
1662 				 udata->inlen - sizeof(req)))
1663 		return ERR_PTR(-EOPNOTSUPP);
1664 
1665 	ndescs = req.num_klms ? roundup(req.num_klms, 4) : roundup(1, 4);
1666 
1667 	mw = kzalloc(sizeof(*mw), GFP_KERNEL);
1668 	in = kzalloc(inlen, GFP_KERNEL);
1669 	if (!mw || !in) {
1670 		err = -ENOMEM;
1671 		goto free;
1672 	}
1673 
1674 	mkc = MLX5_ADDR_OF(create_mkey_in, in, memory_key_mkey_entry);
1675 
1676 	MLX5_SET(mkc, mkc, free, 1);
1677 	MLX5_SET(mkc, mkc, translations_octword_size, ndescs);
1678 	MLX5_SET(mkc, mkc, pd, to_mpd(pd)->pdn);
1679 	MLX5_SET(mkc, mkc, umr_en, 1);
1680 	MLX5_SET(mkc, mkc, lr, 1);
1681 	MLX5_SET(mkc, mkc, access_mode, MLX5_MKC_ACCESS_MODE_KLMS);
1682 	MLX5_SET(mkc, mkc, en_rinval, !!((type == IB_MW_TYPE_2)));
1683 	MLX5_SET(mkc, mkc, qpn, 0xffffff);
1684 
1685 	err = mlx5_core_create_mkey(dev->mdev, &mw->mmkey, in, inlen);
1686 	if (err)
1687 		goto free;
1688 
1689 	mw->mmkey.type = MLX5_MKEY_MW;
1690 	mw->ibmw.rkey = mw->mmkey.key;
1691 	mw->ndescs = ndescs;
1692 
1693 	resp.response_length = min(offsetof(typeof(resp), response_length) +
1694 				   sizeof(resp.response_length), udata->outlen);
1695 	if (resp.response_length) {
1696 		err = ib_copy_to_udata(udata, &resp, resp.response_length);
1697 		if (err) {
1698 			mlx5_core_destroy_mkey(dev->mdev, &mw->mmkey);
1699 			goto free;
1700 		}
1701 	}
1702 
1703 	kfree(in);
1704 	return &mw->ibmw;
1705 
1706 free:
1707 	kfree(mw);
1708 	kfree(in);
1709 	return ERR_PTR(err);
1710 }
1711 
1712 int mlx5_ib_dealloc_mw(struct ib_mw *mw)
1713 {
1714 	struct mlx5_ib_mw *mmw = to_mmw(mw);
1715 	int err;
1716 
1717 	err =  mlx5_core_destroy_mkey((to_mdev(mw->device))->mdev,
1718 				      &mmw->mmkey);
1719 	if (!err)
1720 		kfree(mmw);
1721 	return err;
1722 }
1723 
1724 int mlx5_ib_check_mr_status(struct ib_mr *ibmr, u32 check_mask,
1725 			    struct ib_mr_status *mr_status)
1726 {
1727 	struct mlx5_ib_mr *mmr = to_mmr(ibmr);
1728 	int ret = 0;
1729 
1730 	if (check_mask & ~IB_MR_CHECK_SIG_STATUS) {
1731 		pr_err("Invalid status check mask\n");
1732 		ret = -EINVAL;
1733 		goto done;
1734 	}
1735 
1736 	mr_status->fail_status = 0;
1737 	if (check_mask & IB_MR_CHECK_SIG_STATUS) {
1738 		if (!mmr->sig) {
1739 			ret = -EINVAL;
1740 			pr_err("signature status check requested on a non-signature enabled MR\n");
1741 			goto done;
1742 		}
1743 
1744 		mmr->sig->sig_status_checked = true;
1745 		if (!mmr->sig->sig_err_exists)
1746 			goto done;
1747 
1748 		if (ibmr->lkey == mmr->sig->err_item.key)
1749 			memcpy(&mr_status->sig_err, &mmr->sig->err_item,
1750 			       sizeof(mr_status->sig_err));
1751 		else {
1752 			mr_status->sig_err.err_type = IB_SIG_BAD_GUARD;
1753 			mr_status->sig_err.sig_err_offset = 0;
1754 			mr_status->sig_err.key = mmr->sig->err_item.key;
1755 		}
1756 
1757 		mmr->sig->sig_err_exists = false;
1758 		mr_status->fail_status |= IB_MR_CHECK_SIG_STATUS;
1759 	}
1760 
1761 done:
1762 	return ret;
1763 }
1764 
1765 static int
1766 mlx5_ib_sg_to_klms(struct mlx5_ib_mr *mr,
1767 		   struct scatterlist *sgl,
1768 		   unsigned short sg_nents,
1769 		   unsigned int *sg_offset_p)
1770 {
1771 	struct scatterlist *sg = sgl;
1772 	struct mlx5_klm *klms = mr->descs;
1773 	unsigned int sg_offset = sg_offset_p ? *sg_offset_p : 0;
1774 	u32 lkey = mr->ibmr.pd->local_dma_lkey;
1775 	int i;
1776 
1777 	mr->ibmr.iova = sg_dma_address(sg) + sg_offset;
1778 	mr->ibmr.length = 0;
1779 	mr->ndescs = sg_nents;
1780 
1781 	for_each_sg(sgl, sg, sg_nents, i) {
1782 		if (unlikely(i > mr->max_descs))
1783 			break;
1784 		klms[i].va = cpu_to_be64(sg_dma_address(sg) + sg_offset);
1785 		klms[i].bcount = cpu_to_be32(sg_dma_len(sg) - sg_offset);
1786 		klms[i].key = cpu_to_be32(lkey);
1787 		mr->ibmr.length += sg_dma_len(sg) - sg_offset;
1788 
1789 		sg_offset = 0;
1790 	}
1791 
1792 	if (sg_offset_p)
1793 		*sg_offset_p = sg_offset;
1794 
1795 	return i;
1796 }
1797 
1798 static int mlx5_set_page(struct ib_mr *ibmr, u64 addr)
1799 {
1800 	struct mlx5_ib_mr *mr = to_mmr(ibmr);
1801 	__be64 *descs;
1802 
1803 	if (unlikely(mr->ndescs == mr->max_descs))
1804 		return -ENOMEM;
1805 
1806 	descs = mr->descs;
1807 	descs[mr->ndescs++] = cpu_to_be64(addr | MLX5_EN_RD | MLX5_EN_WR);
1808 
1809 	return 0;
1810 }
1811 
1812 int mlx5_ib_map_mr_sg(struct ib_mr *ibmr, struct scatterlist *sg, int sg_nents,
1813 		      unsigned int *sg_offset)
1814 {
1815 	struct mlx5_ib_mr *mr = to_mmr(ibmr);
1816 	int n;
1817 
1818 	mr->ndescs = 0;
1819 
1820 	ib_dma_sync_single_for_cpu(ibmr->device, mr->desc_map,
1821 				   mr->desc_size * mr->max_descs,
1822 				   DMA_TO_DEVICE);
1823 
1824 	if (mr->access_mode == MLX5_MKC_ACCESS_MODE_KLMS)
1825 		n = mlx5_ib_sg_to_klms(mr, sg, sg_nents, sg_offset);
1826 	else
1827 		n = ib_sg_to_pages(ibmr, sg, sg_nents, sg_offset,
1828 				mlx5_set_page);
1829 
1830 	ib_dma_sync_single_for_device(ibmr->device, mr->desc_map,
1831 				      mr->desc_size * mr->max_descs,
1832 				      DMA_TO_DEVICE);
1833 
1834 	return n;
1835 }
1836