summaryrefslogtreecommitdiffstats
path: root/drivers/vdpa/mlx5/core/mr.c
blob: a639b9208d4148b045210bcb687556cd7ba602ff (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
/* Copyright (c) 2020 Mellanox Technologies Ltd. */

#include <linux/vhost_types.h>
#include <linux/vdpa.h>
#include <linux/gcd.h>
#include <linux/string.h>
#include <linux/mlx5/qp.h>
#include "mlx5_vdpa.h"

/* DIV_ROUND_UP where the divider is a power of 2 give by its log base 2 value */
#define MLX5_DIV_ROUND_UP_POW2(_n, _s) \
({ \
	u64 __s = _s; \
	u64 _res; \
	_res = (((_n) + (1 << (__s)) - 1) >> (__s)); \
	_res; \
})

static int get_octo_len(u64 len, int page_shift)
{
	u64 page_size = 1ULL << page_shift;
	int npages;

	npages = ALIGN(len, page_size) >> page_shift;
	return (npages + 1) / 2;
}

static void mlx5_set_access_mode(void *mkc, int mode)
{
	MLX5_SET(mkc, mkc, access_mode_1_0, mode & 0x3);
	MLX5_SET(mkc, mkc, access_mode_4_2, mode >> 2);
}

static void populate_mtts(struct mlx5_vdpa_direct_mr *mr, __be64 *mtt)
{
	struct scatterlist *sg;
	int nsg = mr->nsg;
	u64 dma_addr;
	u64 dma_len;
	int j = 0;
	int i;

	for_each_sg(mr->sg_head.sgl, sg, mr->nent, i) {
		for (dma_addr = sg_dma_address(sg), dma_len = sg_dma_len(sg);
		     nsg && dma_len;
		     nsg--, dma_addr += BIT(mr->log_size), dma_len -= BIT(mr->log_size))
			mtt[j++] = cpu_to_be64(dma_addr);
	}
}

static int create_direct_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_direct_mr *mr)
{
	int inlen;
	void *mkc;
	void *in;
	int err;

	inlen = MLX5_ST_SZ_BYTES(create_mkey_in) + roundup(MLX5_ST_SZ_BYTES(mtt) * mr->nsg, 16);
	in = kvzalloc(inlen, GFP_KERNEL);
	if (!in)
		return -ENOMEM;

	MLX5_SET(create_mkey_in, in, uid, mvdev->res.uid);
	mkc = MLX5_ADDR_OF(create_mkey_in, in, memory_key_mkey_entry);
	MLX5_SET(mkc, mkc, lw, !!(mr->perm & VHOST_MAP_WO));
	MLX5_SET(mkc, mkc, lr, !!(mr->perm & VHOST_MAP_RO));
	mlx5_set_access_mode(mkc, MLX5_MKC_ACCESS_MODE_MTT);
	MLX5_SET(mkc, mkc, qpn, 0xffffff);
	MLX5_SET(mkc, mkc, pd, mvdev->res.pdn);
	MLX5_SET64(mkc, mkc, start_addr, mr->offset);
	MLX5_SET64(mkc, mkc, len, mr->end - mr->start);
	MLX5_SET(mkc, mkc, log_page_size, mr->log_size);
	MLX5_SET(mkc, mkc, translations_octword_size,
		 get_octo_len(mr->end - mr->start, mr->log_size));
	MLX5_SET(create_mkey_in, in, translations_octword_actual_size,
		 get_octo_len(mr->end - mr->start, mr->log_size));
	populate_mtts(mr, MLX5_ADDR_OF(create_mkey_in, in, klm_pas_mtt));
	err = mlx5_vdpa_create_mkey(mvdev, &mr->mr, in, inlen);
	kvfree(in);
	if (err) {
		mlx5_vdpa_warn(mvdev, "Failed to create direct MR\n");
		return err;
	}

	return 0;
}

static void destroy_direct_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_direct_mr *mr)
{
	mlx5_vdpa_destroy_mkey(mvdev, mr->mr);
}

static u64 map_start(struct vhost_iotlb_map *map, struct mlx5_vdpa_direct_mr *mr)
{
	return max_t(u64, map->start, mr->start);
}

static u64 map_end(struct vhost_iotlb_map *map, struct mlx5_vdpa_direct_mr *mr)
{
	return min_t(u64, map->last + 1, mr->end);
}

static u64 maplen(struct vhost_iotlb_map *map, struct mlx5_vdpa_direct_mr *mr)
{
	return map_end(map, mr) - map_start(map, mr);
}

#define MLX5_VDPA_INVALID_START_ADDR ((u64)-1)
#define MLX5_VDPA_INVALID_LEN ((u64)-1)

static u64 indir_start_addr(struct mlx5_vdpa_mr *mkey)
{
	struct mlx5_vdpa_direct_mr *s;

	s = list_first_entry_or_null(&mkey->head, struct mlx5_vdpa_direct_mr, list);
	if (!s)
		return MLX5_VDPA_INVALID_START_ADDR;

	return s->start;
}

static u64 indir_len(struct mlx5_vdpa_mr *mkey)
{
	struct mlx5_vdpa_direct_mr *s;
	struct mlx5_vdpa_direct_mr *e;

	s = list_first_entry_or_null(&mkey->head, struct mlx5_vdpa_direct_mr, list);
	if (!s)
		return MLX5_VDPA_INVALID_LEN;

	e = list_last_entry(&mkey->head, struct mlx5_vdpa_direct_mr, list);

	return e->end - s->start;
}

#define LOG_MAX_KLM_SIZE 30
#define MAX_KLM_SIZE BIT(LOG_MAX_KLM_SIZE)

static u32 klm_bcount(u64 size)
{
	return (u32)size;
}

static void fill_indir(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_mr *mkey, void *in)
{
	struct mlx5_vdpa_direct_mr *dmr;
	struct mlx5_klm *klmarr;
	struct mlx5_klm *klm;
	bool first = true;
	u64 preve;
	int i;

	klmarr = MLX5_ADDR_OF(create_mkey_in, in, klm_pas_mtt);
	i = 0;
	list_for_each_entry(dmr, &mkey->head, list) {
again:
		klm = &klmarr[i++];
		if (first) {
			preve = dmr->start;
			first = false;
		}

		if (preve == dmr->start) {
			klm->key = cpu_to_be32(dmr->mr);
			klm->bcount = cpu_to_be32(klm_bcount(dmr->end - dmr->start));
			preve = dmr->end;
		} else {
			klm->key = cpu_to_be32(mvdev->res.null_mkey);
			klm->bcount = cpu_to_be32(klm_bcount(dmr->start - preve));
			preve = dmr->start;
			goto again;
		}
	}
}

static int klm_byte_size(int nklms)
{
	return 16 * ALIGN(nklms, 4);
}

static int create_indirect_key(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_mr *mr)
{
	int inlen;
	void *mkc;
	void *in;
	int err;
	u64 start;
	u64 len;

	start = indir_start_addr(mr);
	len = indir_len(mr);
	if (start == MLX5_VDPA_INVALID_START_ADDR || len == MLX5_VDPA_INVALID_LEN)
		return -EINVAL;

	inlen = MLX5_ST_SZ_BYTES(create_mkey_in) + klm_byte_size(mr->num_klms);
	in = kzalloc(inlen, GFP_KERNEL);
	if (!in)
		return -ENOMEM;

	MLX5_SET(create_mkey_in, in, uid, mvdev->res.uid);
	mkc = MLX5_ADDR_OF(create_mkey_in, in, memory_key_mkey_entry);
	MLX5_SET(mkc, mkc, lw, 1);
	MLX5_SET(mkc, mkc, lr, 1);
	mlx5_set_access_mode(mkc, MLX5_MKC_ACCESS_MODE_KLMS);
	MLX5_SET(mkc, mkc, qpn, 0xffffff);
	MLX5_SET(mkc, mkc, pd, mvdev->res.pdn);
	MLX5_SET64(mkc, mkc, start_addr, start);
	MLX5_SET64(mkc, mkc, len, len);
	MLX5_SET(mkc, mkc, translations_octword_size, klm_byte_size(mr->num_klms) / 16);
	MLX5_SET(create_mkey_in, in, translations_octword_actual_size, mr->num_klms);
	fill_indir(mvdev, mr, in);
	err = mlx5_vdpa_create_mkey(mvdev, &mr->mkey, in, inlen);
	kfree(in);
	return err;
}

static void destroy_indirect_key(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_mr *mkey)
{
	mlx5_vdpa_destroy_mkey(mvdev, mkey->mkey);
}

static int map_direct_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_direct_mr *mr,
			 struct vhost_iotlb *iotlb)
{
	struct vhost_iotlb_map *map;
	unsigned long lgcd = 0;
	int log_entity_size;
	unsigned long size;
	u64 start = 0;
	int err;
	struct page *pg;
	unsigned int nsg;
	int sglen;
	u64 pa;
	u64 paend;
	struct scatterlist *sg;
	struct device *dma = mvdev->vdev.dma_dev;

	for (map = vhost_iotlb_itree_first(iotlb, mr->start, mr->end - 1);
	     map; map = vhost_iotlb_itree_next(map, start, mr->end - 1)) {
		size = maplen(map, mr);
		lgcd = gcd(lgcd, size);
		start += size;
	}
	log_entity_size = ilog2(lgcd);

	sglen = 1 << log_entity_size;
	nsg = MLX5_DIV_ROUND_UP_POW2(mr->end - mr->start, log_entity_size);

	err = sg_alloc_table(&mr->sg_head, nsg, GFP_KERNEL);
	if (err)
		return err;

	sg = mr->sg_head.sgl;
	for (map = vhost_iotlb_itree_first(iotlb, mr->start, mr->end - 1);
	     map; map = vhost_iotlb_itree_next(map, mr->start, mr->end - 1)) {
		paend = map->addr + maplen(map, mr);
		for (pa = map->addr; pa < paend; pa += sglen) {
			pg = pfn_to_page(__phys_to_pfn(pa));
			if (!sg) {
				mlx5_vdpa_warn(mvdev, "sg null. start 0x%llx, end 0x%llx\n",
					       map->start, map->last + 1);
				err = -ENOMEM;
				goto err_map;
			}
			sg_set_page(sg, pg, sglen, 0);
			sg = sg_next(sg);
			if (!sg)
				goto done;
		}
	}
done:
	mr->log_size = log_entity_size;
	mr->nsg = nsg;
	mr->nent = dma_map_sg_attrs(dma, mr->sg_head.sgl, mr->nsg, DMA_BIDIRECTIONAL, 0);
	if (!mr->nent) {
		err = -ENOMEM;
		goto err_map;
	}

	err = create_direct_mr(mvdev, mr);
	if (err)
		goto err_direct;

	return 0;

err_direct:
	dma_unmap_sg_attrs(dma, mr->sg_head.sgl, mr->nsg, DMA_BIDIRECTIONAL, 0);
err_map:
	sg_free_table(&mr->sg_head);
	return err;
}

static void unmap_direct_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_direct_mr *mr)
{
	struct device *dma = mvdev->vdev.dma_dev;

	destroy_direct_mr(mvdev, mr);
	dma_unmap_sg_attrs(dma, mr->sg_head.sgl, mr->nsg, DMA_BIDIRECTIONAL, 0);
	sg_free_table(&mr->sg_head);
}

static int add_direct_chain(struct mlx5_vdpa_dev *mvdev, u64 start, u64 size, u8 perm,
			    struct vhost_iotlb *iotlb)
{
	struct mlx5_vdpa_mr *mr = &mvdev->mr;
	struct mlx5_vdpa_direct_mr *dmr;
	struct mlx5_vdpa_direct_mr *n;
	LIST_HEAD(tmp);
	u64 st;
	u64 sz;
	int err;
	int i = 0;

	st = start;
	while (size) {
		sz = (u32)min_t(u64, MAX_KLM_SIZE, size);
		dmr = kzalloc(sizeof(*dmr), GFP_KERNEL);
		if (!dmr) {
			err = -ENOMEM;
			goto err_alloc;
		}

		dmr->start = st;
		dmr->end = st + sz;
		dmr->perm = perm;
		err = map_direct_mr(mvdev, dmr, iotlb);
		if (err) {
			kfree(dmr);
			goto err_alloc;
		}

		list_add_tail(&dmr->list, &tmp);
		size -= sz;
		mr->num_directs++;
		mr->num_klms++;
		st += sz;
		i++;
	}
	list_splice_tail(&tmp, &mr->head);
	return 0;

err_alloc:
	list_for_each_entry_safe(dmr, n, &mr->head, list) {
		list_del_init(&dmr->list);
		unmap_direct_mr(mvdev, dmr);
		kfree(dmr);
	}
	return err;
}

/* The iotlb pointer contains a list of maps. Go over the maps, possibly
 * merging mergeable maps, and create direct memory keys that provide the
 * device access to memory. The direct mkeys are then referred to by the
 * indirect memory key that provides access to the enitre address space given
 * by iotlb.
 */
static int create_user_mr(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb)
{
	struct mlx5_vdpa_mr *mr = &mvdev->mr;
	struct mlx5_vdpa_direct_mr *dmr;
	struct mlx5_vdpa_direct_mr *n;
	struct vhost_iotlb_map *map;
	u32 pperm = U16_MAX;
	u64 last = U64_MAX;
	u64 ps = U64_MAX;
	u64 pe = U64_MAX;
	u64 start = 0;
	int err = 0;
	int nnuls;

	INIT_LIST_HEAD(&mr->head);
	for (map = vhost_iotlb_itree_first(iotlb, start, last); map;
	     map = vhost_iotlb_itree_next(map, start, last)) {
		start = map->start;
		if (pe == map->start && pperm == map->perm) {
			pe = map->last + 1;
		} else {
			if (ps != U64_MAX) {
				if (pe < map->start) {
					/* We have a hole in the map. Check how
					 * many null keys are required to fill it.
					 */
					nnuls = MLX5_DIV_ROUND_UP_POW2(map->start - pe,
								       LOG_MAX_KLM_SIZE);
					mr->num_klms += nnuls;
				}
				err = add_direct_chain(mvdev, ps, pe - ps, pperm, iotlb);
				if (err)
					goto err_chain;
			}
			ps = map->start;
			pe = map->last + 1;
			pperm = map->perm;
		}
	}
	err = add_direct_chain(mvdev, ps, pe - ps, pperm, iotlb);
	if (err)
		goto err_chain;

	/* Create the memory key that defines the guests's address space. This
	 * memory key refers to the direct keys that contain the MTT
	 * translations
	 */
	err = create_indirect_key(mvdev, mr);
	if (err)
		goto err_chain;

	mr->user_mr = true;
	return 0;

err_chain:
	list_for_each_entry_safe_reverse(dmr, n, &mr->head, list) {
		list_del_init(&dmr->list);
		unmap_direct_mr(mvdev, dmr);
		kfree(dmr);
	}
	return err;
}

static int create_dma_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_mr *mr)
{
	int inlen = MLX5_ST_SZ_BYTES(create_mkey_in);
	void *mkc;
	u32 *in;
	int err;

	in = kzalloc(inlen, GFP_KERNEL);
	if (!in)
		return -ENOMEM;

	mkc = MLX5_ADDR_OF(create_mkey_in, in, memory_key_mkey_entry);

	MLX5_SET(mkc, mkc, access_mode_1_0, MLX5_MKC_ACCESS_MODE_PA);
	MLX5_SET(mkc, mkc, length64, 1);
	MLX5_SET(mkc, mkc, lw, 1);
	MLX5_SET(mkc, mkc, lr, 1);
	MLX5_SET(mkc, mkc, pd, mvdev->res.pdn);
	MLX5_SET(mkc, mkc, qpn, 0xffffff);

	err = mlx5_vdpa_create_mkey(mvdev, &mr->mkey, in, inlen);
	if (!err)
		mr->user_mr = false;

	kfree(in);
	return err;
}

static void destroy_dma_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_mr *mr)
{
	mlx5_vdpa_destroy_mkey(mvdev, mr->mkey);
}

static int dup_iotlb(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *src)
{
	struct vhost_iotlb_map *map;
	u64 start = 0, last = ULLONG_MAX;
	int err;

	if (!src) {
		err = vhost_iotlb_add_range(mvdev->cvq.iotlb, start, last, start, VHOST_ACCESS_RW);
		return err;
	}

	for (map = vhost_iotlb_itree_first(src, start, last); map;
		map = vhost_iotlb_itree_next(map, start, last)) {
		err = vhost_iotlb_add_range(mvdev->cvq.iotlb, map->start, map->last,
					    map->addr, map->perm);
		if (err)
			return err;
	}
	return 0;
}

static void prune_iotlb(struct mlx5_vdpa_dev *mvdev)
{
	vhost_iotlb_del_range(mvdev->cvq.iotlb, 0, ULLONG_MAX);
}

static void destroy_user_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_mr *mr)
{
	struct mlx5_vdpa_direct_mr *dmr;
	struct mlx5_vdpa_direct_mr *n;

	destroy_indirect_key(mvdev, mr);
	list_for_each_entry_safe_reverse(dmr, n, &mr->head, list) {
		list_del_init(&dmr->list);
		unmap_direct_mr(mvdev, dmr);
		kfree(dmr);
	}
}

void mlx5_vdpa_destroy_mr(struct mlx5_vdpa_dev *mvdev)
{
	struct mlx5_vdpa_mr *mr = &mvdev->mr;

	mutex_lock(&mr->mkey_mtx);
	if (!mr->initialized)
		goto out;

	prune_iotlb(mvdev);
	if (mr->user_mr)
		destroy_user_mr(mvdev, mr);
	else
		destroy_dma_mr(mvdev, mr);

	memset(mr, 0, sizeof(*mr));
	mr->initialized = false;
out:
	mutex_unlock(&mr->mkey_mtx);
}

static int _mlx5_vdpa_create_mr(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb)
{
	struct mlx5_vdpa_mr *mr = &mvdev->mr;
	int err;

	if (mr->initialized)
		return 0;

	if (iotlb)
		err = create_user_mr(mvdev, iotlb);
	else
		err = create_dma_mr(mvdev, mr);

	if (err)
		return err;

	err = dup_iotlb(mvdev, iotlb);
	if (err)
		goto out_err;

	mr->initialized = true;
	return 0;

out_err:
	if (iotlb)
		destroy_user_mr(mvdev, mr);
	else
		destroy_dma_mr(mvdev, mr);

	return err;
}

int mlx5_vdpa_create_mr(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb)
{
	int err;

	mutex_lock(&mvdev->mr.mkey_mtx);
	err = _mlx5_vdpa_create_mr(mvdev, iotlb);
	mutex_unlock(&mvdev->mr.mkey_mtx);
	return err;
}

int mlx5_vdpa_handle_set_map(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb,
			     bool *change_map)
{
	struct mlx5_vdpa_mr *mr = &mvdev->mr;
	int err = 0;

	*change_map = false;
	mutex_lock(&mr->mkey_mtx);
	if (mr->initialized) {
		mlx5_vdpa_info(mvdev, "memory map update\n");
		*change_map = true;
	}
	if (!*change_map)
		err = _mlx5_vdpa_create_mr(mvdev, iotlb);
	mutex_unlock(&mr->mkey_mtx);

	return err;
}