summaryrefslogtreecommitdiff
path: root/drivers/nvme/host/lightnvm.c
blob: f23e6fefd2627912a75ffbffd7cb5b4896390bf1 (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
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
/*
 * nvme-lightnvm.c - LightNVM NVMe device
 *
 * Copyright (C) 2014-2015 IT University of Copenhagen
 * Initial release: Matias Bjorling <mb@lightnvm.io>
 *
 * 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.
 *
 */

#include "nvme.h"

#include <linux/nvme.h>
#include <linux/bitops.h>
#include <linux/lightnvm.h>
#include <linux/vmalloc.h>

enum nvme_nvm_admin_opcode {
	nvme_nvm_admin_identity		= 0xe2,
	nvme_nvm_admin_get_l2p_tbl	= 0xea,
	nvme_nvm_admin_get_bb_tbl	= 0xf2,
	nvme_nvm_admin_set_bb_tbl	= 0xf1,
};

struct nvme_nvm_hb_rw {
	__u8			opcode;
	__u8			flags;
	__u16			command_id;
	__le32			nsid;
	__u64			rsvd2;
	__le64			metadata;
	__le64			prp1;
	__le64			prp2;
	__le64			spba;
	__le16			length;
	__le16			control;
	__le32			dsmgmt;
	__le64			slba;
};

struct nvme_nvm_ph_rw {
	__u8			opcode;
	__u8			flags;
	__u16			command_id;
	__le32			nsid;
	__u64			rsvd2;
	__le64			metadata;
	__le64			prp1;
	__le64			prp2;
	__le64			spba;
	__le16			length;
	__le16			control;
	__le32			dsmgmt;
	__le64			resv;
};

struct nvme_nvm_identity {
	__u8			opcode;
	__u8			flags;
	__u16			command_id;
	__le32			nsid;
	__u64			rsvd[2];
	__le64			prp1;
	__le64			prp2;
	__le32			chnl_off;
	__u32			rsvd11[5];
};

struct nvme_nvm_l2ptbl {
	__u8			opcode;
	__u8			flags;
	__u16			command_id;
	__le32			nsid;
	__le32			cdw2[4];
	__le64			prp1;
	__le64			prp2;
	__le64			slba;
	__le32			nlb;
	__le16			cdw14[6];
};

struct nvme_nvm_getbbtbl {
	__u8			opcode;
	__u8			flags;
	__u16			command_id;
	__le32			nsid;
	__u64			rsvd[2];
	__le64			prp1;
	__le64			prp2;
	__le64			spba;
	__u32			rsvd4[4];
};

struct nvme_nvm_setbbtbl {
	__u8			opcode;
	__u8			flags;
	__u16			command_id;
	__le32			nsid;
	__le64			rsvd[2];
	__le64			prp1;
	__le64			prp2;
	__le64			spba;
	__le16			nlb;
	__u8			value;
	__u8			rsvd3;
	__u32			rsvd4[3];
};

struct nvme_nvm_erase_blk {
	__u8			opcode;
	__u8			flags;
	__u16			command_id;
	__le32			nsid;
	__u64			rsvd[2];
	__le64			prp1;
	__le64			prp2;
	__le64			spba;
	__le16			length;
	__le16			control;
	__le32			dsmgmt;
	__le64			resv;
};

struct nvme_nvm_command {
	union {
		struct nvme_common_command common;
		struct nvme_nvm_identity identity;
		struct nvme_nvm_hb_rw hb_rw;
		struct nvme_nvm_ph_rw ph_rw;
		struct nvme_nvm_l2ptbl l2p;
		struct nvme_nvm_getbbtbl get_bb;
		struct nvme_nvm_setbbtbl set_bb;
		struct nvme_nvm_erase_blk erase;
	};
};

#define NVME_NVM_LP_MLC_PAIRS 886
struct nvme_nvm_lp_mlc {
	__le16			num_pairs;
	__u8			pairs[NVME_NVM_LP_MLC_PAIRS];
};

struct nvme_nvm_lp_tbl {
	__u8			id[8];
	struct nvme_nvm_lp_mlc	mlc;
};

struct nvme_nvm_id_group {
	__u8			mtype;
	__u8			fmtype;
	__le16			res16;
	__u8			num_ch;
	__u8			num_lun;
	__u8			num_pln;
	__u8			rsvd1;
	__le16			num_blk;
	__le16			num_pg;
	__le16			fpg_sz;
	__le16			csecs;
	__le16			sos;
	__le16			rsvd2;
	__le32			trdt;
	__le32			trdm;
	__le32			tprt;
	__le32			tprm;
	__le32			tbet;
	__le32			tbem;
	__le32			mpos;
	__le32			mccap;
	__le16			cpar;
	__u8			reserved[10];
	struct nvme_nvm_lp_tbl lptbl;
} __packed;

struct nvme_nvm_addr_format {
	__u8			ch_offset;
	__u8			ch_len;
	__u8			lun_offset;
	__u8			lun_len;
	__u8			pln_offset;
	__u8			pln_len;
	__u8			blk_offset;
	__u8			blk_len;
	__u8			pg_offset;
	__u8			pg_len;
	__u8			sect_offset;
	__u8			sect_len;
	__u8			res[4];
} __packed;

struct nvme_nvm_id {
	__u8			ver_id;
	__u8			vmnt;
	__u8			cgrps;
	__u8			res;
	__le32			cap;
	__le32			dom;
	struct nvme_nvm_addr_format ppaf;
	__u8			resv[228];
	struct nvme_nvm_id_group groups[4];
} __packed;

struct nvme_nvm_bb_tbl {
	__u8	tblid[4];
	__le16	verid;
	__le16	revid;
	__le32	rvsd1;
	__le32	tblks;
	__le32	tfact;
	__le32	tgrown;
	__le32	tdresv;
	__le32	thresv;
	__le32	rsvd2[8];
	__u8	blk[0];
};

/*
 * Check we didn't inadvertently grow the command struct
 */
static inline void _nvme_nvm_check_size(void)
{
	BUILD_BUG_ON(sizeof(struct nvme_nvm_identity) != 64);
	BUILD_BUG_ON(sizeof(struct nvme_nvm_hb_rw) != 64);
	BUILD_BUG_ON(sizeof(struct nvme_nvm_ph_rw) != 64);
	BUILD_BUG_ON(sizeof(struct nvme_nvm_getbbtbl) != 64);
	BUILD_BUG_ON(sizeof(struct nvme_nvm_setbbtbl) != 64);
	BUILD_BUG_ON(sizeof(struct nvme_nvm_l2ptbl) != 64);
	BUILD_BUG_ON(sizeof(struct nvme_nvm_erase_blk) != 64);
	BUILD_BUG_ON(sizeof(struct nvme_nvm_id_group) != 960);
	BUILD_BUG_ON(sizeof(struct nvme_nvm_addr_format) != 128);
	BUILD_BUG_ON(sizeof(struct nvme_nvm_id) != 4096);
	BUILD_BUG_ON(sizeof(struct nvme_nvm_bb_tbl) != 512);
}

static int init_grps(struct nvm_id *nvm_id, struct nvme_nvm_id *nvme_nvm_id)
{
	struct nvme_nvm_id_group *src;
	struct nvm_id_group *dst;
	int i, end;

	end = min_t(u32, 4, nvm_id->cgrps);

	for (i = 0; i < end; i++) {
		src = &nvme_nvm_id->groups[i];
		dst = &nvm_id->groups[i];

		dst->mtype = src->mtype;
		dst->fmtype = src->fmtype;
		dst->num_ch = src->num_ch;
		dst->num_lun = src->num_lun;
		dst->num_pln = src->num_pln;

		dst->num_pg = le16_to_cpu(src->num_pg);
		dst->num_blk = le16_to_cpu(src->num_blk);
		dst->fpg_sz = le16_to_cpu(src->fpg_sz);
		dst->csecs = le16_to_cpu(src->csecs);
		dst->sos = le16_to_cpu(src->sos);

		dst->trdt = le32_to_cpu(src->trdt);
		dst->trdm = le32_to_cpu(src->trdm);
		dst->tprt = le32_to_cpu(src->tprt);
		dst->tprm = le32_to_cpu(src->tprm);
		dst->tbet = le32_to_cpu(src->tbet);
		dst->tbem = le32_to_cpu(src->tbem);
		dst->mpos = le32_to_cpu(src->mpos);
		dst->mccap = le32_to_cpu(src->mccap);

		dst->cpar = le16_to_cpu(src->cpar);

		if (dst->fmtype == NVM_ID_FMTYPE_MLC) {
			memcpy(dst->lptbl.id, src->lptbl.id, 8);
			dst->lptbl.mlc.num_pairs =
					le16_to_cpu(src->lptbl.mlc.num_pairs);

			if (dst->lptbl.mlc.num_pairs > NVME_NVM_LP_MLC_PAIRS) {
				pr_err("nvm: number of MLC pairs not supported\n");
				return -EINVAL;
			}

			memcpy(dst->lptbl.mlc.pairs, src->lptbl.mlc.pairs,
						dst->lptbl.mlc.num_pairs);
		}
	}

	return 0;
}

static int nvme_nvm_identity(struct nvm_dev *nvmdev, struct nvm_id *nvm_id)
{
	struct nvme_ns *ns = nvmdev->q->queuedata;
	struct nvme_nvm_id *nvme_nvm_id;
	struct nvme_nvm_command c = {};
	int ret;

	c.identity.opcode = nvme_nvm_admin_identity;
	c.identity.nsid = cpu_to_le32(ns->ns_id);
	c.identity.chnl_off = 0;

	nvme_nvm_id = kmalloc(sizeof(struct nvme_nvm_id), GFP_KERNEL);
	if (!nvme_nvm_id)
		return -ENOMEM;

	ret = nvme_submit_sync_cmd(ns->ctrl->admin_q, (struct nvme_command *)&c,
				nvme_nvm_id, sizeof(struct nvme_nvm_id));
	if (ret) {
		ret = -EIO;
		goto out;
	}

	nvm_id->ver_id = nvme_nvm_id->ver_id;
	nvm_id->vmnt = nvme_nvm_id->vmnt;
	nvm_id->cgrps = nvme_nvm_id->cgrps;
	nvm_id->cap = le32_to_cpu(nvme_nvm_id->cap);
	nvm_id->dom = le32_to_cpu(nvme_nvm_id->dom);
	memcpy(&nvm_id->ppaf, &nvme_nvm_id->ppaf,
					sizeof(struct nvme_nvm_addr_format));

	ret = init_grps(nvm_id, nvme_nvm_id);
out:
	kfree(nvme_nvm_id);
	return ret;
}

static int nvme_nvm_get_l2p_tbl(struct nvm_dev *nvmdev, u64 slba, u32 nlb,
				nvm_l2p_update_fn *update_l2p, void *priv)
{
	struct nvme_ns *ns = nvmdev->q->queuedata;
	struct nvme_nvm_command c = {};
	u32 len = queue_max_hw_sectors(ns->ctrl->admin_q) << 9;
	u32 nlb_pr_rq = len / sizeof(u64);
	u64 cmd_slba = slba;
	void *entries;
	int ret = 0;

	c.l2p.opcode = nvme_nvm_admin_get_l2p_tbl;
	c.l2p.nsid = cpu_to_le32(ns->ns_id);
	entries = kmalloc(len, GFP_KERNEL);
	if (!entries)
		return -ENOMEM;

	while (nlb) {
		u32 cmd_nlb = min(nlb_pr_rq, nlb);

		c.l2p.slba = cpu_to_le64(cmd_slba);
		c.l2p.nlb = cpu_to_le32(cmd_nlb);

		ret = nvme_submit_sync_cmd(ns->ctrl->admin_q,
				(struct nvme_command *)&c, entries, len);
		if (ret) {
			dev_err(ns->ctrl->device,
				"L2P table transfer failed (%d)\n", ret);
			ret = -EIO;
			goto out;
		}

		if (update_l2p(cmd_slba, cmd_nlb, entries, priv)) {
			ret = -EINTR;
			goto out;
		}

		cmd_slba += cmd_nlb;
		nlb -= cmd_nlb;
	}

out:
	kfree(entries);
	return ret;
}

static int nvme_nvm_get_bb_tbl(struct nvm_dev *nvmdev, struct ppa_addr ppa,
								u8 *blks)
{
	struct request_queue *q = nvmdev->q;
	struct nvme_ns *ns = q->queuedata;
	struct nvme_ctrl *ctrl = ns->ctrl;
	struct nvme_nvm_command c = {};
	struct nvme_nvm_bb_tbl *bb_tbl;
	int nr_blks = nvmdev->blks_per_lun * nvmdev->plane_mode;
	int tblsz = sizeof(struct nvme_nvm_bb_tbl) + nr_blks;
	int ret = 0;

	c.get_bb.opcode = nvme_nvm_admin_get_bb_tbl;
	c.get_bb.nsid = cpu_to_le32(ns->ns_id);
	c.get_bb.spba = cpu_to_le64(ppa.ppa);

	bb_tbl = kzalloc(tblsz, GFP_KERNEL);
	if (!bb_tbl)
		return -ENOMEM;

	ret = nvme_submit_sync_cmd(ctrl->admin_q, (struct nvme_command *)&c,
								bb_tbl, tblsz);
	if (ret) {
		dev_err(ctrl->device, "get bad block table failed (%d)\n", ret);
		ret = -EIO;
		goto out;
	}

	if (bb_tbl->tblid[0] != 'B' || bb_tbl->tblid[1] != 'B' ||
		bb_tbl->tblid[2] != 'L' || bb_tbl->tblid[3] != 'T') {
		dev_err(ctrl->device, "bbt format mismatch\n");
		ret = -EINVAL;
		goto out;
	}

	if (le16_to_cpu(bb_tbl->verid) != 1) {
		ret = -EINVAL;
		dev_err(ctrl->device, "bbt version not supported\n");
		goto out;
	}

	if (le32_to_cpu(bb_tbl->tblks) != nr_blks) {
		ret = -EINVAL;
		dev_err(ctrl->device,
				"bbt unsuspected blocks returned (%u!=%u)",
				le32_to_cpu(bb_tbl->tblks), nr_blks);
		goto out;
	}

	memcpy(blks, bb_tbl->blk, nvmdev->blks_per_lun * nvmdev->plane_mode);
out:
	kfree(bb_tbl);
	return ret;
}

static int nvme_nvm_set_bb_tbl(struct nvm_dev *nvmdev, struct ppa_addr *ppas,
							int nr_ppas, int type)
{
	struct nvme_ns *ns = nvmdev->q->queuedata;
	struct nvme_nvm_command c = {};
	int ret = 0;

	c.set_bb.opcode = nvme_nvm_admin_set_bb_tbl;
	c.set_bb.nsid = cpu_to_le32(ns->ns_id);
	c.set_bb.spba = cpu_to_le64(ppas->ppa);
	c.set_bb.nlb = cpu_to_le16(nr_ppas - 1);
	c.set_bb.value = type;

	ret = nvme_submit_sync_cmd(ns->ctrl->admin_q, (struct nvme_command *)&c,
								NULL, 0);
	if (ret)
		dev_err(ns->ctrl->device, "set bad block table failed (%d)\n",
									ret);
	return ret;
}

static inline void nvme_nvm_rqtocmd(struct request *rq, struct nvm_rq *rqd,
				struct nvme_ns *ns, struct nvme_nvm_command *c)
{
	c->ph_rw.opcode = rqd->opcode;
	c->ph_rw.nsid = cpu_to_le32(ns->ns_id);
	c->ph_rw.spba = cpu_to_le64(rqd->ppa_addr.ppa);
	c->ph_rw.metadata = cpu_to_le64(rqd->dma_meta_list);
	c->ph_rw.control = cpu_to_le16(rqd->flags);
	c->ph_rw.length = cpu_to_le16(rqd->nr_ppas - 1);

	if (rqd->opcode == NVM_OP_HBWRITE || rqd->opcode == NVM_OP_HBREAD)
		c->hb_rw.slba = cpu_to_le64(nvme_block_nr(ns,
					rqd->bio->bi_iter.bi_sector));
}

static void nvme_nvm_end_io(struct request *rq, int error)
{
	struct nvm_rq *rqd = rq->end_io_data;

	rqd->ppa_status = nvme_req(rq)->result.u64;
	nvm_end_io(rqd, error);

	kfree(nvme_req(rq)->cmd);
	blk_mq_free_request(rq);
}

static int nvme_nvm_submit_io(struct nvm_dev *dev, struct nvm_rq *rqd)
{
	struct request_queue *q = dev->q;
	struct nvme_ns *ns = q->queuedata;
	struct request *rq;
	struct bio *bio = rqd->bio;
	struct nvme_nvm_command *cmd;

	cmd = kzalloc(sizeof(struct nvme_nvm_command), GFP_KERNEL);
	if (!cmd)
		return -ENOMEM;

	rq = nvme_alloc_request(q, (struct nvme_command *)cmd, 0, NVME_QID_ANY);
	if (IS_ERR(rq)) {
		kfree(cmd);
		return -ENOMEM;
	}
	rq->cmd_flags &= ~REQ_FAILFAST_DRIVER;

	rq->ioprio = bio_prio(bio);
	if (bio_has_data(bio))
		rq->nr_phys_segments = bio_phys_segments(q, bio);

	rq->__data_len = bio->bi_iter.bi_size;
	rq->bio = rq->biotail = bio;

	nvme_nvm_rqtocmd(rq, rqd, ns, cmd);

	rq->end_io_data = rqd;

	blk_execute_rq_nowait(q, NULL, rq, 0, nvme_nvm_end_io);

	return 0;
}

static int nvme_nvm_erase_block(struct nvm_dev *dev, struct nvm_rq *rqd)
{
	struct request_queue *q = dev->q;
	struct nvme_ns *ns = q->queuedata;
	struct nvme_nvm_command c = {};

	c.erase.opcode = NVM_OP_ERASE;
	c.erase.nsid = cpu_to_le32(ns->ns_id);
	c.erase.spba = cpu_to_le64(rqd->ppa_addr.ppa);
	c.erase.length = cpu_to_le16(rqd->nr_ppas - 1);

	return nvme_submit_sync_cmd(q, (struct nvme_command *)&c, NULL, 0);
}

static void *nvme_nvm_create_dma_pool(struct nvm_dev *nvmdev, char *name)
{
	struct nvme_ns *ns = nvmdev->q->queuedata;

	return dma_pool_create(name, ns->ctrl->dev, PAGE_SIZE, PAGE_SIZE, 0);
}

static void nvme_nvm_destroy_dma_pool(void *pool)
{
	struct dma_pool *dma_pool = pool;

	dma_pool_destroy(dma_pool);
}

static void *nvme_nvm_dev_dma_alloc(struct nvm_dev *dev, void *pool,
				    gfp_t mem_flags, dma_addr_t *dma_handler)
{
	return dma_pool_alloc(pool, mem_flags, dma_handler);
}

static void nvme_nvm_dev_dma_free(void *pool, void *addr,
							dma_addr_t dma_handler)
{
	dma_pool_free(pool, addr, dma_handler);
}

static struct nvm_dev_ops nvme_nvm_dev_ops = {
	.identity		= nvme_nvm_identity,

	.get_l2p_tbl		= nvme_nvm_get_l2p_tbl,

	.get_bb_tbl		= nvme_nvm_get_bb_tbl,
	.set_bb_tbl		= nvme_nvm_set_bb_tbl,

	.submit_io		= nvme_nvm_submit_io,
	.erase_block		= nvme_nvm_erase_block,

	.create_dma_pool	= nvme_nvm_create_dma_pool,
	.destroy_dma_pool	= nvme_nvm_destroy_dma_pool,
	.dev_dma_alloc		= nvme_nvm_dev_dma_alloc,
	.dev_dma_free		= nvme_nvm_dev_dma_free,

	.max_phys_sect		= 64,
};

int nvme_nvm_register(struct nvme_ns *ns, char *disk_name, int node)
{
	struct request_queue *q = ns->queue;
	struct nvm_dev *dev;

	dev = nvm_alloc_dev(node);
	if (!dev)
		return -ENOMEM;

	dev->q = q;
	memcpy(dev->name, disk_name, DISK_NAME_LEN);
	dev->ops = &nvme_nvm_dev_ops;
	dev->private_data = ns;
	ns->ndev = dev;

	return nvm_register(dev);
}

void nvme_nvm_unregister(struct nvme_ns *ns)
{
	nvm_unregister(ns->ndev);
}

static ssize_t nvm_dev_attr_show(struct device *dev,
				 struct device_attribute *dattr, char *page)
{
	struct nvme_ns *ns = nvme_get_ns_from_dev(dev);
	struct nvm_dev *ndev = ns->ndev;
	struct nvm_id *id;
	struct nvm_id_group *grp;
	struct attribute *attr;

	if (!ndev)
		return 0;

	id = &ndev->identity;
	grp = &id->groups[0];
	attr = &dattr->attr;

	if (strcmp(attr->name, "version") == 0) {
		return scnprintf(page, PAGE_SIZE, "%u\n", id->ver_id);
	} else if (strcmp(attr->name, "vendor_opcode") == 0) {
		return scnprintf(page, PAGE_SIZE, "%u\n", id->vmnt);
	} else if (strcmp(attr->name, "capabilities") == 0) {
		return scnprintf(page, PAGE_SIZE, "%u\n", id->cap);
	} else if (strcmp(attr->name, "device_mode") == 0) {
		return scnprintf(page, PAGE_SIZE, "%u\n", id->dom);
	} else if (strcmp(attr->name, "media_manager") == 0) {
		if (!ndev->mt)
			return scnprintf(page, PAGE_SIZE, "%s\n", "none");
		return scnprintf(page, PAGE_SIZE, "%s\n", ndev->mt->name);
	} else if (strcmp(attr->name, "ppa_format") == 0) {
		return scnprintf(page, PAGE_SIZE,
			"0x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x\n",
			id->ppaf.ch_offset, id->ppaf.ch_len,
			id->ppaf.lun_offset, id->ppaf.lun_len,
			id->ppaf.pln_offset, id->ppaf.pln_len,
			id->ppaf.blk_offset, id->ppaf.blk_len,
			id->ppaf.pg_offset, id->ppaf.pg_len,
			id->ppaf.sect_offset, id->ppaf.sect_len);
	} else if (strcmp(attr->name, "media_type") == 0) {	/* u8 */
		return scnprintf(page, PAGE_SIZE, "%u\n", grp->mtype);
	} else if (strcmp(attr->name, "flash_media_type") == 0) {
		return scnprintf(page, PAGE_SIZE, "%u\n", grp->fmtype);
	} else if (strcmp(attr->name, "num_channels") == 0) {
		return scnprintf(page, PAGE_SIZE, "%u\n", grp->num_ch);
	} else if (strcmp(attr->name, "num_luns") == 0) {
		return scnprintf(page, PAGE_SIZE, "%u\n", grp->num_lun);
	} else if (strcmp(attr->name, "num_planes") == 0) {
		return scnprintf(page, PAGE_SIZE, "%u\n", grp->num_pln);
	} else if (strcmp(attr->name, "num_blocks") == 0) {	/* u16 */
		return scnprintf(page, PAGE_SIZE, "%u\n", grp->num_blk);
	} else if (strcmp(attr->name, "num_pages") == 0) {
		return scnprintf(page, PAGE_SIZE, "%u\n", grp->num_pg);
	} else if (strcmp(attr->name, "page_size") == 0) {
		return scnprintf(page, PAGE_SIZE, "%u\n", grp->fpg_sz);
	} else if (strcmp(attr->name, "hw_sector_size") == 0) {
		return scnprintf(page, PAGE_SIZE, "%u\n", grp->csecs);
	} else if (strcmp(attr->name, "oob_sector_size") == 0) {/* u32 */
		return scnprintf(page, PAGE_SIZE, "%u\n", grp->sos);
	} else if (strcmp(attr->name, "read_typ") == 0) {
		return scnprintf(page, PAGE_SIZE, "%u\n", grp->trdt);
	} else if (strcmp(attr->name, "read_max") == 0) {
		return scnprintf(page, PAGE_SIZE, "%u\n", grp->trdm);
	} else if (strcmp(attr->name, "prog_typ") == 0) {
		return scnprintf(page, PAGE_SIZE, "%u\n", grp->tprt);
	} else if (strcmp(attr->name, "prog_max") == 0) {
		return scnprintf(page, PAGE_SIZE, "%u\n", grp->tprm);
	} else if (strcmp(attr->name, "erase_typ") == 0) {
		return scnprintf(page, PAGE_SIZE, "%u\n", grp->tbet);
	} else if (strcmp(attr->name, "erase_max") == 0) {
		return scnprintf(page, PAGE_SIZE, "%u\n", grp->tbem);
	} else if (strcmp(attr->name, "multiplane_modes") == 0) {
		return scnprintf(page, PAGE_SIZE, "0x%08x\n", grp->mpos);
	} else if (strcmp(attr->name, "media_capabilities") == 0) {
		return scnprintf(page, PAGE_SIZE, "0x%08x\n", grp->mccap);
	} else if (strcmp(attr->name, "max_phys_secs") == 0) {
		return scnprintf(page, PAGE_SIZE, "%u\n",
				ndev->ops->max_phys_sect);
	} else {
		return scnprintf(page,
				 PAGE_SIZE,
				 "Unhandled attr(%s) in `nvm_dev_attr_show`\n",
				 attr->name);
	}
}

#define NVM_DEV_ATTR_RO(_name)						\
	DEVICE_ATTR(_name, S_IRUGO, nvm_dev_attr_show, NULL)

static NVM_DEV_ATTR_RO(version);
static NVM_DEV_ATTR_RO(vendor_opcode);
static NVM_DEV_ATTR_RO(capabilities);
static NVM_DEV_ATTR_RO(device_mode);
static NVM_DEV_ATTR_RO(ppa_format);
static NVM_DEV_ATTR_RO(media_manager);

static NVM_DEV_ATTR_RO(media_type);
static NVM_DEV_ATTR_RO(flash_media_type);
static NVM_DEV_ATTR_RO(num_channels);
static NVM_DEV_ATTR_RO(num_luns);
static NVM_DEV_ATTR_RO(num_planes);
static NVM_DEV_ATTR_RO(num_blocks);
static NVM_DEV_ATTR_RO(num_pages);
static NVM_DEV_ATTR_RO(page_size);
static NVM_DEV_ATTR_RO(hw_sector_size);
static NVM_DEV_ATTR_RO(oob_sector_size);
static NVM_DEV_ATTR_RO(read_typ);
static NVM_DEV_ATTR_RO(read_max);
static NVM_DEV_ATTR_RO(prog_typ);
static NVM_DEV_ATTR_RO(prog_max);
static NVM_DEV_ATTR_RO(erase_typ);
static NVM_DEV_ATTR_RO(erase_max);
static NVM_DEV_ATTR_RO(multiplane_modes);
static NVM_DEV_ATTR_RO(media_capabilities);
static NVM_DEV_ATTR_RO(max_phys_secs);

static struct attribute *nvm_dev_attrs[] = {
	&dev_attr_version.attr,
	&dev_attr_vendor_opcode.attr,
	&dev_attr_capabilities.attr,
	&dev_attr_device_mode.attr,
	&dev_attr_media_manager.attr,

	&dev_attr_ppa_format.attr,
	&dev_attr_media_type.attr,
	&dev_attr_flash_media_type.attr,
	&dev_attr_num_channels.attr,
	&dev_attr_num_luns.attr,
	&dev_attr_num_planes.attr,
	&dev_attr_num_blocks.attr,
	&dev_attr_num_pages.attr,
	&dev_attr_page_size.attr,
	&dev_attr_hw_sector_size.attr,
	&dev_attr_oob_sector_size.attr,
	&dev_attr_read_typ.attr,
	&dev_attr_read_max.attr,
	&dev_attr_prog_typ.attr,
	&dev_attr_prog_max.attr,
	&dev_attr_erase_typ.attr,
	&dev_attr_erase_max.attr,
	&dev_attr_multiplane_modes.attr,
	&dev_attr_media_capabilities.attr,
	&dev_attr_max_phys_secs.attr,
	NULL,
};

static const struct attribute_group nvm_dev_attr_group = {
	.name		= "lightnvm",
	.attrs		= nvm_dev_attrs,
};

int nvme_nvm_register_sysfs(struct nvme_ns *ns)
{
	return sysfs_create_group(&disk_to_dev(ns->disk)->kobj,
					&nvm_dev_attr_group);
}

void nvme_nvm_unregister_sysfs(struct nvme_ns *ns)
{
	sysfs_remove_group(&disk_to_dev(ns->disk)->kobj,
					&nvm_dev_attr_group);
}

/* move to shared place when used in multiple places. */
#define PCI_VENDOR_ID_CNEX 0x1d1d
#define PCI_DEVICE_ID_CNEX_WL 0x2807
#define PCI_DEVICE_ID_CNEX_QEMU 0x1f1f

int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id)
{
	struct nvme_ctrl *ctrl = ns->ctrl;
	/* XXX: this is poking into PCI structures from generic code! */
	struct pci_dev *pdev = to_pci_dev(ctrl->dev);

	/* QEMU NVMe simulator - PCI ID + Vendor specific bit */
	if (pdev->vendor == PCI_VENDOR_ID_CNEX &&
				pdev->device == PCI_DEVICE_ID_CNEX_QEMU &&
							id->vs[0] == 0x1)
		return 1;

	/* CNEX Labs - PCI ID + Vendor specific bit */
	if (pdev->vendor == PCI_VENDOR_ID_CNEX &&
				pdev->device == PCI_DEVICE_ID_CNEX_WL &&
							id->vs[0] == 0x1)
		return 1;

	return 0;
}