summaryrefslogtreecommitdiffstats
path: root/drivers/lightnvm/gennvm.c
blob: ae1fb2bdc5f44b25aecdf010afdf9894de0dfede (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
/*
 * Copyright (C) 2015 Matias Bjorling <m@bjorling.me>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License version
 * 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; see the file COPYING.  If not, write to
 * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
 * USA.
 *
 * Implementation of a generic nvm manager for Open-Channel SSDs.
 */

#include "gennvm.h"

static void gennvm_blocks_free(struct nvm_dev *dev)
{
	struct gen_nvm *gn = dev->mp;
	struct gen_lun *lun;
	int i;

	gennvm_for_each_lun(gn, lun, i) {
		if (!lun->vlun.blocks)
			break;
		vfree(lun->vlun.blocks);
	}
}

static void gennvm_luns_free(struct nvm_dev *dev)
{
	struct gen_nvm *gn = dev->mp;

	kfree(gn->luns);
}

static int gennvm_luns_init(struct nvm_dev *dev, struct gen_nvm *gn)
{
	struct gen_lun *lun;
	int i;

	gn->luns = kcalloc(dev->nr_luns, sizeof(struct gen_lun), GFP_KERNEL);
	if (!gn->luns)
		return -ENOMEM;

	gennvm_for_each_lun(gn, lun, i) {
		spin_lock_init(&lun->vlun.lock);
		INIT_LIST_HEAD(&lun->free_list);
		INIT_LIST_HEAD(&lun->used_list);
		INIT_LIST_HEAD(&lun->bb_list);

		lun->reserved_blocks = 2; /* for GC only */
		lun->vlun.id = i;
		lun->vlun.lun_id = i % dev->luns_per_chnl;
		lun->vlun.chnl_id = i / dev->luns_per_chnl;
		lun->vlun.nr_free_blocks = dev->blks_per_lun;
	}
	return 0;
}

static int gennvm_block_bb(u32 lun_id, void *bb_bitmap, unsigned int nr_blocks,
								void *private)
{
	struct gen_nvm *gn = private;
	struct gen_lun *lun = &gn->luns[lun_id];
	struct nvm_block *blk;
	int i;

	if (unlikely(bitmap_empty(bb_bitmap, nr_blocks)))
		return 0;

	i = -1;
	while ((i = find_next_bit(bb_bitmap, nr_blocks, i + 1)) < nr_blocks) {
		blk = &lun->vlun.blocks[i];
		if (!blk) {
			pr_err("gennvm: BB data is out of bounds.\n");
			return -EINVAL;
		}

		list_move_tail(&blk->list, &lun->bb_list);
	}

	return 0;
}

static int gennvm_block_map(u64 slba, u32 nlb, __le64 *entries, void *private)
{
	struct nvm_dev *dev = private;
	struct gen_nvm *gn = dev->mp;
	sector_t max_pages = dev->total_pages * (dev->sec_size >> 9);
	u64 elba = slba + nlb;
	struct gen_lun *lun;
	struct nvm_block *blk;
	u64 i;
	int lun_id;

	if (unlikely(elba > dev->total_pages)) {
		pr_err("gennvm: L2P data from device is out of bounds!\n");
		return -EINVAL;
	}

	for (i = 0; i < nlb; i++) {
		u64 pba = le64_to_cpu(entries[i]);

		if (unlikely(pba >= max_pages && pba != U64_MAX)) {
			pr_err("gennvm: L2P data entry is out of bounds!\n");
			return -EINVAL;
		}

		/* Address zero is a special one. The first page on a disk is
		 * protected. It often holds internal device boot
		 * information.
		 */
		if (!pba)
			continue;

		/* resolve block from physical address */
		lun_id = div_u64(pba, dev->sec_per_lun);
		lun = &gn->luns[lun_id];

		/* Calculate block offset into lun */
		pba = pba - (dev->sec_per_lun * lun_id);
		blk = &lun->vlun.blocks[div_u64(pba, dev->sec_per_blk)];

		if (!blk->type) {
			/* at this point, we don't know anything about the
			 * block. It's up to the FTL on top to re-etablish the
			 * block state
			 */
			list_move_tail(&blk->list, &lun->used_list);
			blk->type = 1;
			lun->vlun.nr_free_blocks--;
		}
	}

	return 0;
}

static int gennvm_blocks_init(struct nvm_dev *dev, struct gen_nvm *gn)
{
	struct gen_lun *lun;
	struct nvm_block *block;
	sector_t lun_iter, blk_iter, cur_block_id = 0;
	int ret;

	gennvm_for_each_lun(gn, lun, lun_iter) {
		lun->vlun.blocks = vzalloc(sizeof(struct nvm_block) *
							dev->blks_per_lun);
		if (!lun->vlun.blocks)
			return -ENOMEM;

		for (blk_iter = 0; blk_iter < dev->blks_per_lun; blk_iter++) {
			block = &lun->vlun.blocks[blk_iter];

			INIT_LIST_HEAD(&block->list);

			block->lun = &lun->vlun;
			block->id = cur_block_id++;

			/* First block is reserved for device */
			if (unlikely(lun_iter == 0 && blk_iter == 0))
				continue;

			list_add_tail(&block->list, &lun->free_list);
		}

		if (dev->ops->get_bb_tbl) {
			ret = dev->ops->get_bb_tbl(dev->q, lun->vlun.id,
					dev->blks_per_lun, gennvm_block_bb, gn);
			if (ret)
				pr_err("gennvm: could not read BB table\n");
		}
	}

	if (dev->ops->get_l2p_tbl) {
		ret = dev->ops->get_l2p_tbl(dev->q, 0, dev->total_pages,
							gennvm_block_map, dev);
		if (ret) {
			pr_err("gennvm: could not read L2P table.\n");
			pr_warn("gennvm: default block initialization");
		}
	}

	return 0;
}

static int gennvm_register(struct nvm_dev *dev)
{
	struct gen_nvm *gn;
	int ret;

	gn = kzalloc(sizeof(struct gen_nvm), GFP_KERNEL);
	if (!gn)
		return -ENOMEM;

	gn->nr_luns = dev->nr_luns;
	dev->mp = gn;

	ret = gennvm_luns_init(dev, gn);
	if (ret) {
		pr_err("gennvm: could not initialize luns\n");
		goto err;
	}

	ret = gennvm_blocks_init(dev, gn);
	if (ret) {
		pr_err("gennvm: could not initialize blocks\n");
		goto err;
	}

	return 1;
err:
	kfree(gn);
	return ret;
}

static void gennvm_unregister(struct nvm_dev *dev)
{
	gennvm_blocks_free(dev);
	gennvm_luns_free(dev);
	kfree(dev->mp);
	dev->mp = NULL;
}

static struct nvm_block *gennvm_get_blk(struct nvm_dev *dev,
				struct nvm_lun *vlun, unsigned long flags)
{
	struct gen_lun *lun = container_of(vlun, struct gen_lun, vlun);
	struct nvm_block *blk = NULL;
	int is_gc = flags & NVM_IOTYPE_GC;

	spin_lock(&vlun->lock);

	if (list_empty(&lun->free_list)) {
		pr_err_ratelimited("gennvm: lun %u have no free pages available",
								lun->vlun.id);
		spin_unlock(&vlun->lock);
		goto out;
	}

	while (!is_gc && lun->vlun.nr_free_blocks < lun->reserved_blocks) {
		spin_unlock(&vlun->lock);
		goto out;
	}

	blk = list_first_entry(&lun->free_list, struct nvm_block, list);
	list_move_tail(&blk->list, &lun->used_list);
	blk->type = 1;

	lun->vlun.nr_free_blocks--;

	spin_unlock(&vlun->lock);
out:
	return blk;
}

static void gennvm_put_blk(struct nvm_dev *dev, struct nvm_block *blk)
{
	struct nvm_lun *vlun = blk->lun;
	struct gen_lun *lun = container_of(vlun, struct gen_lun, vlun);

	spin_lock(&vlun->lock);

	switch (blk->type) {
	case 1:
		list_move_tail(&blk->list, &lun->free_list);
		lun->vlun.nr_free_blocks++;
		blk->type = 0;
		break;
	case 2:
		list_move_tail(&blk->list, &lun->bb_list);
		break;
	default:
		WARN_ON_ONCE(1);
		pr_err("gennvm: erroneous block type (%lu -> %u)\n",
							blk->id, blk->type);
		list_move_tail(&blk->list, &lun->bb_list);
	}

	spin_unlock(&vlun->lock);
}

static void gennvm_addr_to_generic_mode(struct nvm_dev *dev, struct nvm_rq *rqd)
{
	int i;

	if (rqd->nr_pages > 1) {
		for (i = 0; i < rqd->nr_pages; i++)
			rqd->ppa_list[i] = addr_to_generic_mode(dev,
							rqd->ppa_list[i]);
	} else {
		rqd->ppa_addr = addr_to_generic_mode(dev, rqd->ppa_addr);
	}
}

static void gennvm_generic_to_addr_mode(struct nvm_dev *dev, struct nvm_rq *rqd)
{
	int i;

	if (rqd->nr_pages > 1) {
		for (i = 0; i < rqd->nr_pages; i++)
			rqd->ppa_list[i] = generic_to_addr_mode(dev,
							rqd->ppa_list[i]);
	} else {
		rqd->ppa_addr = generic_to_addr_mode(dev, rqd->ppa_addr);
	}
}

static int gennvm_submit_io(struct nvm_dev *dev, struct nvm_rq *rqd)
{
	if (!dev->ops->submit_io)
		return 0;

	/* Convert address space */
	gennvm_generic_to_addr_mode(dev, rqd);

	rqd->dev = dev;
	return dev->ops->submit_io(dev->q, rqd);
}

static void gennvm_blk_set_type(struct nvm_dev *dev, struct ppa_addr *ppa,
								int type)
{
	struct gen_nvm *gn = dev->mp;
	struct gen_lun *lun;
	struct nvm_block *blk;

	if (unlikely(ppa->g.ch > dev->nr_chnls ||
					ppa->g.lun > dev->luns_per_chnl ||
					ppa->g.blk > dev->blks_per_lun)) {
		WARN_ON_ONCE(1);
		pr_err("gennvm: ppa broken (ch: %u > %u lun: %u > %u blk: %u > %u",
				ppa->g.ch, dev->nr_chnls,
				ppa->g.lun, dev->luns_per_chnl,
				ppa->g.blk, dev->blks_per_lun);
		return;
	}

	lun = &gn->luns[ppa->g.lun * ppa->g.ch];
	blk = &lun->vlun.blocks[ppa->g.blk];

	/* will be moved to bb list on put_blk from target */
	blk->type = type;
}

/* mark block bad. It is expected the target recover from the error. */
static void gennvm_mark_blk_bad(struct nvm_dev *dev, struct nvm_rq *rqd)
{
	int i;

	if (!dev->ops->set_bb)
		return;

	if (dev->ops->set_bb(dev->q, rqd, 1))
		return;

	gennvm_addr_to_generic_mode(dev, rqd);

	/* look up blocks and mark them as bad */
	if (rqd->nr_pages > 1)
		for (i = 0; i < rqd->nr_pages; i++)
			gennvm_blk_set_type(dev, &rqd->ppa_list[i], 2);
	else
		gennvm_blk_set_type(dev, &rqd->ppa_addr, 2);
}

static int gennvm_end_io(struct nvm_rq *rqd, int error)
{
	struct nvm_tgt_instance *ins = rqd->ins;
	int ret = 0;

	switch (error) {
	case NVM_RSP_SUCCESS:
		break;
	case NVM_RSP_ERR_EMPTYPAGE:
		break;
	case NVM_RSP_ERR_FAILWRITE:
		gennvm_mark_blk_bad(rqd->dev, rqd);
	default:
		ret++;
	}

	ret += ins->tt->end_io(rqd, error);

	return ret;
}

static int gennvm_erase_blk(struct nvm_dev *dev, struct nvm_block *blk,
							unsigned long flags)
{
	int plane_cnt = 0, pl_idx, ret;
	struct ppa_addr addr;
	struct nvm_rq rqd;

	if (!dev->ops->erase_block)
		return 0;

	addr = block_to_ppa(dev, blk);

	if (dev->plane_mode == NVM_PLANE_SINGLE) {
		rqd.nr_pages = 1;
		rqd.ppa_addr = addr;
	} else {
		plane_cnt = (1 << dev->plane_mode);
		rqd.nr_pages = plane_cnt;

		rqd.ppa_list = nvm_dev_dma_alloc(dev, GFP_KERNEL,
							&rqd.dma_ppa_list);
		if (!rqd.ppa_list) {
			pr_err("gennvm: failed to allocate dma memory\n");
			return -ENOMEM;
		}

		for (pl_idx = 0; pl_idx < plane_cnt; pl_idx++) {
			addr.g.pl = pl_idx;
			rqd.ppa_list[pl_idx] = addr;
		}
	}

	gennvm_generic_to_addr_mode(dev, &rqd);

	ret = dev->ops->erase_block(dev->q, &rqd);

	if (plane_cnt)
		nvm_dev_dma_free(dev, rqd.ppa_list, rqd.dma_ppa_list);

	return ret;
}

static struct nvm_lun *gennvm_get_lun(struct nvm_dev *dev, int lunid)
{
	struct gen_nvm *gn = dev->mp;

	return &gn->luns[lunid].vlun;
}

static void gennvm_free_blocks_print(struct nvm_dev *dev)
{
	struct gen_nvm *gn = dev->mp;
	struct gen_lun *lun;
	unsigned int i;

	gennvm_for_each_lun(gn, lun, i)
		pr_info("%s: lun%8u\t%u\n",
					dev->name, i, lun->vlun.nr_free_blocks);
}

static struct nvmm_type gennvm = {
	.name		= "gennvm",
	.version	= {0, 1, 0},

	.register_mgr	= gennvm_register,
	.unregister_mgr	= gennvm_unregister,

	.get_blk	= gennvm_get_blk,
	.put_blk	= gennvm_put_blk,

	.submit_io	= gennvm_submit_io,
	.end_io		= gennvm_end_io,
	.erase_blk	= gennvm_erase_blk,

	.get_lun	= gennvm_get_lun,
	.free_blocks_print = gennvm_free_blocks_print,
};

static int __init gennvm_module_init(void)
{
	return nvm_register_mgr(&gennvm);
}

static void gennvm_module_exit(void)
{
	nvm_unregister_mgr(&gennvm);
}

module_init(gennvm_module_init);
module_exit(gennvm_module_exit);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Generic media manager for Open-Channel SSDs");