xref: /linux/drivers/nvme/host/core.c (revision 0d08df6c493898e679d9c517e77ea95c063d40ec)
1 /*
2  * NVM Express device driver
3  * Copyright (c) 2011-2014, Intel Corporation.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms and conditions of the GNU General Public License,
7  * version 2, as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  */
14 
15 #include <linux/blkdev.h>
16 #include <linux/blk-mq.h>
17 #include <linux/delay.h>
18 #include <linux/errno.h>
19 #include <linux/hdreg.h>
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/list_sort.h>
23 #include <linux/slab.h>
24 #include <linux/types.h>
25 #include <linux/pr.h>
26 #include <linux/ptrace.h>
27 #include <linux/nvme_ioctl.h>
28 #include <linux/t10-pi.h>
29 #include <scsi/sg.h>
30 #include <asm/unaligned.h>
31 
32 #include "nvme.h"
33 
34 #define NVME_MINORS		(1U << MINORBITS)
35 
36 unsigned char admin_timeout = 60;
37 module_param(admin_timeout, byte, 0644);
38 MODULE_PARM_DESC(admin_timeout, "timeout in seconds for admin commands");
39 EXPORT_SYMBOL_GPL(admin_timeout);
40 
41 unsigned char nvme_io_timeout = 30;
42 module_param_named(io_timeout, nvme_io_timeout, byte, 0644);
43 MODULE_PARM_DESC(io_timeout, "timeout in seconds for I/O");
44 EXPORT_SYMBOL_GPL(nvme_io_timeout);
45 
46 unsigned char shutdown_timeout = 5;
47 module_param(shutdown_timeout, byte, 0644);
48 MODULE_PARM_DESC(shutdown_timeout, "timeout in seconds for controller shutdown");
49 
50 static int nvme_major;
51 module_param(nvme_major, int, 0);
52 
53 static int nvme_char_major;
54 module_param(nvme_char_major, int, 0);
55 
56 static LIST_HEAD(nvme_ctrl_list);
57 static DEFINE_SPINLOCK(dev_list_lock);
58 
59 static struct class *nvme_class;
60 
61 bool nvme_change_ctrl_state(struct nvme_ctrl *ctrl,
62 		enum nvme_ctrl_state new_state)
63 {
64 	enum nvme_ctrl_state old_state = ctrl->state;
65 	bool changed = false;
66 
67 	spin_lock_irq(&ctrl->lock);
68 	switch (new_state) {
69 	case NVME_CTRL_LIVE:
70 		switch (old_state) {
71 		case NVME_CTRL_RESETTING:
72 			changed = true;
73 			/* FALLTHRU */
74 		default:
75 			break;
76 		}
77 		break;
78 	case NVME_CTRL_RESETTING:
79 		switch (old_state) {
80 		case NVME_CTRL_NEW:
81 		case NVME_CTRL_LIVE:
82 			changed = true;
83 			/* FALLTHRU */
84 		default:
85 			break;
86 		}
87 		break;
88 	case NVME_CTRL_DELETING:
89 		switch (old_state) {
90 		case NVME_CTRL_LIVE:
91 		case NVME_CTRL_RESETTING:
92 			changed = true;
93 			/* FALLTHRU */
94 		default:
95 			break;
96 		}
97 		break;
98 	default:
99 		break;
100 	}
101 	spin_unlock_irq(&ctrl->lock);
102 
103 	if (changed)
104 		ctrl->state = new_state;
105 
106 	return changed;
107 }
108 EXPORT_SYMBOL_GPL(nvme_change_ctrl_state);
109 
110 static void nvme_free_ns(struct kref *kref)
111 {
112 	struct nvme_ns *ns = container_of(kref, struct nvme_ns, kref);
113 
114 	if (ns->type == NVME_NS_LIGHTNVM)
115 		nvme_nvm_unregister(ns->queue, ns->disk->disk_name);
116 
117 	spin_lock(&dev_list_lock);
118 	ns->disk->private_data = NULL;
119 	spin_unlock(&dev_list_lock);
120 
121 	put_disk(ns->disk);
122 	ida_simple_remove(&ns->ctrl->ns_ida, ns->instance);
123 	nvme_put_ctrl(ns->ctrl);
124 	kfree(ns);
125 }
126 
127 static void nvme_put_ns(struct nvme_ns *ns)
128 {
129 	kref_put(&ns->kref, nvme_free_ns);
130 }
131 
132 static struct nvme_ns *nvme_get_ns_from_disk(struct gendisk *disk)
133 {
134 	struct nvme_ns *ns;
135 
136 	spin_lock(&dev_list_lock);
137 	ns = disk->private_data;
138 	if (ns) {
139 		if (!kref_get_unless_zero(&ns->kref))
140 			goto fail;
141 		if (!try_module_get(ns->ctrl->ops->module))
142 			goto fail_put_ns;
143 	}
144 	spin_unlock(&dev_list_lock);
145 
146 	return ns;
147 
148 fail_put_ns:
149 	kref_put(&ns->kref, nvme_free_ns);
150 fail:
151 	spin_unlock(&dev_list_lock);
152 	return NULL;
153 }
154 
155 void nvme_requeue_req(struct request *req)
156 {
157 	unsigned long flags;
158 
159 	blk_mq_requeue_request(req);
160 	spin_lock_irqsave(req->q->queue_lock, flags);
161 	if (!blk_queue_stopped(req->q))
162 		blk_mq_kick_requeue_list(req->q);
163 	spin_unlock_irqrestore(req->q->queue_lock, flags);
164 }
165 EXPORT_SYMBOL_GPL(nvme_requeue_req);
166 
167 struct request *nvme_alloc_request(struct request_queue *q,
168 		struct nvme_command *cmd, unsigned int flags)
169 {
170 	bool write = cmd->common.opcode & 1;
171 	struct request *req;
172 
173 	req = blk_mq_alloc_request(q, write, flags);
174 	if (IS_ERR(req))
175 		return req;
176 
177 	req->cmd_type = REQ_TYPE_DRV_PRIV;
178 	req->cmd_flags |= REQ_FAILFAST_DRIVER;
179 	req->__data_len = 0;
180 	req->__sector = (sector_t) -1;
181 	req->bio = req->biotail = NULL;
182 
183 	req->cmd = (unsigned char *)cmd;
184 	req->cmd_len = sizeof(struct nvme_command);
185 
186 	return req;
187 }
188 EXPORT_SYMBOL_GPL(nvme_alloc_request);
189 
190 static inline void nvme_setup_flush(struct nvme_ns *ns,
191 		struct nvme_command *cmnd)
192 {
193 	memset(cmnd, 0, sizeof(*cmnd));
194 	cmnd->common.opcode = nvme_cmd_flush;
195 	cmnd->common.nsid = cpu_to_le32(ns->ns_id);
196 }
197 
198 static inline int nvme_setup_discard(struct nvme_ns *ns, struct request *req,
199 		struct nvme_command *cmnd)
200 {
201 	struct nvme_dsm_range *range;
202 	struct page *page;
203 	int offset;
204 	unsigned int nr_bytes = blk_rq_bytes(req);
205 
206 	range = kmalloc(sizeof(*range), GFP_ATOMIC);
207 	if (!range)
208 		return BLK_MQ_RQ_QUEUE_BUSY;
209 
210 	range->cattr = cpu_to_le32(0);
211 	range->nlb = cpu_to_le32(nr_bytes >> ns->lba_shift);
212 	range->slba = cpu_to_le64(nvme_block_nr(ns, blk_rq_pos(req)));
213 
214 	memset(cmnd, 0, sizeof(*cmnd));
215 	cmnd->dsm.opcode = nvme_cmd_dsm;
216 	cmnd->dsm.nsid = cpu_to_le32(ns->ns_id);
217 	cmnd->dsm.nr = 0;
218 	cmnd->dsm.attributes = cpu_to_le32(NVME_DSMGMT_AD);
219 
220 	req->completion_data = range;
221 	page = virt_to_page(range);
222 	offset = offset_in_page(range);
223 	blk_add_request_payload(req, page, offset, sizeof(*range));
224 
225 	/*
226 	 * we set __data_len back to the size of the area to be discarded
227 	 * on disk. This allows us to report completion on the full amount
228 	 * of blocks described by the request.
229 	 */
230 	req->__data_len = nr_bytes;
231 
232 	return 0;
233 }
234 
235 static inline void nvme_setup_rw(struct nvme_ns *ns, struct request *req,
236 		struct nvme_command *cmnd)
237 {
238 	u16 control = 0;
239 	u32 dsmgmt = 0;
240 
241 	if (req->cmd_flags & REQ_FUA)
242 		control |= NVME_RW_FUA;
243 	if (req->cmd_flags & (REQ_FAILFAST_DEV | REQ_RAHEAD))
244 		control |= NVME_RW_LR;
245 
246 	if (req->cmd_flags & REQ_RAHEAD)
247 		dsmgmt |= NVME_RW_DSM_FREQ_PREFETCH;
248 
249 	memset(cmnd, 0, sizeof(*cmnd));
250 	cmnd->rw.opcode = (rq_data_dir(req) ? nvme_cmd_write : nvme_cmd_read);
251 	cmnd->rw.command_id = req->tag;
252 	cmnd->rw.nsid = cpu_to_le32(ns->ns_id);
253 	cmnd->rw.slba = cpu_to_le64(nvme_block_nr(ns, blk_rq_pos(req)));
254 	cmnd->rw.length = cpu_to_le16((blk_rq_bytes(req) >> ns->lba_shift) - 1);
255 
256 	if (ns->ms) {
257 		switch (ns->pi_type) {
258 		case NVME_NS_DPS_PI_TYPE3:
259 			control |= NVME_RW_PRINFO_PRCHK_GUARD;
260 			break;
261 		case NVME_NS_DPS_PI_TYPE1:
262 		case NVME_NS_DPS_PI_TYPE2:
263 			control |= NVME_RW_PRINFO_PRCHK_GUARD |
264 					NVME_RW_PRINFO_PRCHK_REF;
265 			cmnd->rw.reftag = cpu_to_le32(
266 					nvme_block_nr(ns, blk_rq_pos(req)));
267 			break;
268 		}
269 		if (!blk_integrity_rq(req))
270 			control |= NVME_RW_PRINFO_PRACT;
271 	}
272 
273 	cmnd->rw.control = cpu_to_le16(control);
274 	cmnd->rw.dsmgmt = cpu_to_le32(dsmgmt);
275 }
276 
277 int nvme_setup_cmd(struct nvme_ns *ns, struct request *req,
278 		struct nvme_command *cmd)
279 {
280 	int ret = 0;
281 
282 	if (req->cmd_type == REQ_TYPE_DRV_PRIV)
283 		memcpy(cmd, req->cmd, sizeof(*cmd));
284 	else if (req->cmd_flags & REQ_FLUSH)
285 		nvme_setup_flush(ns, cmd);
286 	else if (req->cmd_flags & REQ_DISCARD)
287 		ret = nvme_setup_discard(ns, req, cmd);
288 	else
289 		nvme_setup_rw(ns, req, cmd);
290 
291 	return ret;
292 }
293 EXPORT_SYMBOL_GPL(nvme_setup_cmd);
294 
295 /*
296  * Returns 0 on success.  If the result is negative, it's a Linux error code;
297  * if the result is positive, it's an NVM Express status code
298  */
299 int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
300 		struct nvme_completion *cqe, void *buffer, unsigned bufflen,
301 		unsigned timeout)
302 {
303 	struct request *req;
304 	int ret;
305 
306 	req = nvme_alloc_request(q, cmd, 0);
307 	if (IS_ERR(req))
308 		return PTR_ERR(req);
309 
310 	req->timeout = timeout ? timeout : ADMIN_TIMEOUT;
311 	req->special = cqe;
312 
313 	if (buffer && bufflen) {
314 		ret = blk_rq_map_kern(q, req, buffer, bufflen, GFP_KERNEL);
315 		if (ret)
316 			goto out;
317 	}
318 
319 	blk_execute_rq(req->q, NULL, req, 0);
320 	ret = req->errors;
321  out:
322 	blk_mq_free_request(req);
323 	return ret;
324 }
325 
326 int nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
327 		void *buffer, unsigned bufflen)
328 {
329 	return __nvme_submit_sync_cmd(q, cmd, NULL, buffer, bufflen, 0);
330 }
331 EXPORT_SYMBOL_GPL(nvme_submit_sync_cmd);
332 
333 int __nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
334 		void __user *ubuffer, unsigned bufflen,
335 		void __user *meta_buffer, unsigned meta_len, u32 meta_seed,
336 		u32 *result, unsigned timeout)
337 {
338 	bool write = cmd->common.opcode & 1;
339 	struct nvme_completion cqe;
340 	struct nvme_ns *ns = q->queuedata;
341 	struct gendisk *disk = ns ? ns->disk : NULL;
342 	struct request *req;
343 	struct bio *bio = NULL;
344 	void *meta = NULL;
345 	int ret;
346 
347 	req = nvme_alloc_request(q, cmd, 0);
348 	if (IS_ERR(req))
349 		return PTR_ERR(req);
350 
351 	req->timeout = timeout ? timeout : ADMIN_TIMEOUT;
352 	req->special = &cqe;
353 
354 	if (ubuffer && bufflen) {
355 		ret = blk_rq_map_user(q, req, NULL, ubuffer, bufflen,
356 				GFP_KERNEL);
357 		if (ret)
358 			goto out;
359 		bio = req->bio;
360 
361 		if (!disk)
362 			goto submit;
363 		bio->bi_bdev = bdget_disk(disk, 0);
364 		if (!bio->bi_bdev) {
365 			ret = -ENODEV;
366 			goto out_unmap;
367 		}
368 
369 		if (meta_buffer && meta_len) {
370 			struct bio_integrity_payload *bip;
371 
372 			meta = kmalloc(meta_len, GFP_KERNEL);
373 			if (!meta) {
374 				ret = -ENOMEM;
375 				goto out_unmap;
376 			}
377 
378 			if (write) {
379 				if (copy_from_user(meta, meta_buffer,
380 						meta_len)) {
381 					ret = -EFAULT;
382 					goto out_free_meta;
383 				}
384 			}
385 
386 			bip = bio_integrity_alloc(bio, GFP_KERNEL, 1);
387 			if (IS_ERR(bip)) {
388 				ret = PTR_ERR(bip);
389 				goto out_free_meta;
390 			}
391 
392 			bip->bip_iter.bi_size = meta_len;
393 			bip->bip_iter.bi_sector = meta_seed;
394 
395 			ret = bio_integrity_add_page(bio, virt_to_page(meta),
396 					meta_len, offset_in_page(meta));
397 			if (ret != meta_len) {
398 				ret = -ENOMEM;
399 				goto out_free_meta;
400 			}
401 		}
402 	}
403  submit:
404 	blk_execute_rq(req->q, disk, req, 0);
405 	ret = req->errors;
406 	if (result)
407 		*result = le32_to_cpu(cqe.result);
408 	if (meta && !ret && !write) {
409 		if (copy_to_user(meta_buffer, meta, meta_len))
410 			ret = -EFAULT;
411 	}
412  out_free_meta:
413 	kfree(meta);
414  out_unmap:
415 	if (bio) {
416 		if (disk && bio->bi_bdev)
417 			bdput(bio->bi_bdev);
418 		blk_rq_unmap_user(bio);
419 	}
420  out:
421 	blk_mq_free_request(req);
422 	return ret;
423 }
424 
425 int nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
426 		void __user *ubuffer, unsigned bufflen, u32 *result,
427 		unsigned timeout)
428 {
429 	return __nvme_submit_user_cmd(q, cmd, ubuffer, bufflen, NULL, 0, 0,
430 			result, timeout);
431 }
432 
433 int nvme_identify_ctrl(struct nvme_ctrl *dev, struct nvme_id_ctrl **id)
434 {
435 	struct nvme_command c = { };
436 	int error;
437 
438 	/* gcc-4.4.4 (at least) has issues with initializers and anon unions */
439 	c.identify.opcode = nvme_admin_identify;
440 	c.identify.cns = cpu_to_le32(1);
441 
442 	*id = kmalloc(sizeof(struct nvme_id_ctrl), GFP_KERNEL);
443 	if (!*id)
444 		return -ENOMEM;
445 
446 	error = nvme_submit_sync_cmd(dev->admin_q, &c, *id,
447 			sizeof(struct nvme_id_ctrl));
448 	if (error)
449 		kfree(*id);
450 	return error;
451 }
452 
453 static int nvme_identify_ns_list(struct nvme_ctrl *dev, unsigned nsid, __le32 *ns_list)
454 {
455 	struct nvme_command c = { };
456 
457 	c.identify.opcode = nvme_admin_identify;
458 	c.identify.cns = cpu_to_le32(2);
459 	c.identify.nsid = cpu_to_le32(nsid);
460 	return nvme_submit_sync_cmd(dev->admin_q, &c, ns_list, 0x1000);
461 }
462 
463 int nvme_identify_ns(struct nvme_ctrl *dev, unsigned nsid,
464 		struct nvme_id_ns **id)
465 {
466 	struct nvme_command c = { };
467 	int error;
468 
469 	/* gcc-4.4.4 (at least) has issues with initializers and anon unions */
470 	c.identify.opcode = nvme_admin_identify,
471 	c.identify.nsid = cpu_to_le32(nsid),
472 
473 	*id = kmalloc(sizeof(struct nvme_id_ns), GFP_KERNEL);
474 	if (!*id)
475 		return -ENOMEM;
476 
477 	error = nvme_submit_sync_cmd(dev->admin_q, &c, *id,
478 			sizeof(struct nvme_id_ns));
479 	if (error)
480 		kfree(*id);
481 	return error;
482 }
483 
484 int nvme_get_features(struct nvme_ctrl *dev, unsigned fid, unsigned nsid,
485 					dma_addr_t dma_addr, u32 *result)
486 {
487 	struct nvme_command c;
488 	struct nvme_completion cqe;
489 	int ret;
490 
491 	memset(&c, 0, sizeof(c));
492 	c.features.opcode = nvme_admin_get_features;
493 	c.features.nsid = cpu_to_le32(nsid);
494 	c.features.prp1 = cpu_to_le64(dma_addr);
495 	c.features.fid = cpu_to_le32(fid);
496 
497 	ret = __nvme_submit_sync_cmd(dev->admin_q, &c, &cqe, NULL, 0, 0);
498 	if (ret >= 0)
499 		*result = le32_to_cpu(cqe.result);
500 	return ret;
501 }
502 
503 int nvme_set_features(struct nvme_ctrl *dev, unsigned fid, unsigned dword11,
504 					dma_addr_t dma_addr, u32 *result)
505 {
506 	struct nvme_command c;
507 	struct nvme_completion cqe;
508 	int ret;
509 
510 	memset(&c, 0, sizeof(c));
511 	c.features.opcode = nvme_admin_set_features;
512 	c.features.prp1 = cpu_to_le64(dma_addr);
513 	c.features.fid = cpu_to_le32(fid);
514 	c.features.dword11 = cpu_to_le32(dword11);
515 
516 	ret = __nvme_submit_sync_cmd(dev->admin_q, &c, &cqe, NULL, 0, 0);
517 	if (ret >= 0)
518 		*result = le32_to_cpu(cqe.result);
519 	return ret;
520 }
521 
522 int nvme_get_log_page(struct nvme_ctrl *dev, struct nvme_smart_log **log)
523 {
524 	struct nvme_command c = { };
525 	int error;
526 
527 	c.common.opcode = nvme_admin_get_log_page,
528 	c.common.nsid = cpu_to_le32(0xFFFFFFFF),
529 	c.common.cdw10[0] = cpu_to_le32(
530 			(((sizeof(struct nvme_smart_log) / 4) - 1) << 16) |
531 			 NVME_LOG_SMART),
532 
533 	*log = kmalloc(sizeof(struct nvme_smart_log), GFP_KERNEL);
534 	if (!*log)
535 		return -ENOMEM;
536 
537 	error = nvme_submit_sync_cmd(dev->admin_q, &c, *log,
538 			sizeof(struct nvme_smart_log));
539 	if (error)
540 		kfree(*log);
541 	return error;
542 }
543 
544 int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count)
545 {
546 	u32 q_count = (*count - 1) | ((*count - 1) << 16);
547 	u32 result;
548 	int status, nr_io_queues;
549 
550 	status = nvme_set_features(ctrl, NVME_FEAT_NUM_QUEUES, q_count, 0,
551 			&result);
552 	if (status)
553 		return status;
554 
555 	nr_io_queues = min(result & 0xffff, result >> 16) + 1;
556 	*count = min(*count, nr_io_queues);
557 	return 0;
558 }
559 EXPORT_SYMBOL_GPL(nvme_set_queue_count);
560 
561 static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio)
562 {
563 	struct nvme_user_io io;
564 	struct nvme_command c;
565 	unsigned length, meta_len;
566 	void __user *metadata;
567 
568 	if (copy_from_user(&io, uio, sizeof(io)))
569 		return -EFAULT;
570 	if (io.flags)
571 		return -EINVAL;
572 
573 	switch (io.opcode) {
574 	case nvme_cmd_write:
575 	case nvme_cmd_read:
576 	case nvme_cmd_compare:
577 		break;
578 	default:
579 		return -EINVAL;
580 	}
581 
582 	length = (io.nblocks + 1) << ns->lba_shift;
583 	meta_len = (io.nblocks + 1) * ns->ms;
584 	metadata = (void __user *)(uintptr_t)io.metadata;
585 
586 	if (ns->ext) {
587 		length += meta_len;
588 		meta_len = 0;
589 	} else if (meta_len) {
590 		if ((io.metadata & 3) || !io.metadata)
591 			return -EINVAL;
592 	}
593 
594 	memset(&c, 0, sizeof(c));
595 	c.rw.opcode = io.opcode;
596 	c.rw.flags = io.flags;
597 	c.rw.nsid = cpu_to_le32(ns->ns_id);
598 	c.rw.slba = cpu_to_le64(io.slba);
599 	c.rw.length = cpu_to_le16(io.nblocks);
600 	c.rw.control = cpu_to_le16(io.control);
601 	c.rw.dsmgmt = cpu_to_le32(io.dsmgmt);
602 	c.rw.reftag = cpu_to_le32(io.reftag);
603 	c.rw.apptag = cpu_to_le16(io.apptag);
604 	c.rw.appmask = cpu_to_le16(io.appmask);
605 
606 	return __nvme_submit_user_cmd(ns->queue, &c,
607 			(void __user *)(uintptr_t)io.addr, length,
608 			metadata, meta_len, io.slba, NULL, 0);
609 }
610 
611 static int nvme_user_cmd(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
612 			struct nvme_passthru_cmd __user *ucmd)
613 {
614 	struct nvme_passthru_cmd cmd;
615 	struct nvme_command c;
616 	unsigned timeout = 0;
617 	int status;
618 
619 	if (!capable(CAP_SYS_ADMIN))
620 		return -EACCES;
621 	if (copy_from_user(&cmd, ucmd, sizeof(cmd)))
622 		return -EFAULT;
623 	if (cmd.flags)
624 		return -EINVAL;
625 
626 	memset(&c, 0, sizeof(c));
627 	c.common.opcode = cmd.opcode;
628 	c.common.flags = cmd.flags;
629 	c.common.nsid = cpu_to_le32(cmd.nsid);
630 	c.common.cdw2[0] = cpu_to_le32(cmd.cdw2);
631 	c.common.cdw2[1] = cpu_to_le32(cmd.cdw3);
632 	c.common.cdw10[0] = cpu_to_le32(cmd.cdw10);
633 	c.common.cdw10[1] = cpu_to_le32(cmd.cdw11);
634 	c.common.cdw10[2] = cpu_to_le32(cmd.cdw12);
635 	c.common.cdw10[3] = cpu_to_le32(cmd.cdw13);
636 	c.common.cdw10[4] = cpu_to_le32(cmd.cdw14);
637 	c.common.cdw10[5] = cpu_to_le32(cmd.cdw15);
638 
639 	if (cmd.timeout_ms)
640 		timeout = msecs_to_jiffies(cmd.timeout_ms);
641 
642 	status = nvme_submit_user_cmd(ns ? ns->queue : ctrl->admin_q, &c,
643 			(void __user *)(uintptr_t)cmd.addr, cmd.data_len,
644 			&cmd.result, timeout);
645 	if (status >= 0) {
646 		if (put_user(cmd.result, &ucmd->result))
647 			return -EFAULT;
648 	}
649 
650 	return status;
651 }
652 
653 static int nvme_ioctl(struct block_device *bdev, fmode_t mode,
654 		unsigned int cmd, unsigned long arg)
655 {
656 	struct nvme_ns *ns = bdev->bd_disk->private_data;
657 
658 	switch (cmd) {
659 	case NVME_IOCTL_ID:
660 		force_successful_syscall_return();
661 		return ns->ns_id;
662 	case NVME_IOCTL_ADMIN_CMD:
663 		return nvme_user_cmd(ns->ctrl, NULL, (void __user *)arg);
664 	case NVME_IOCTL_IO_CMD:
665 		return nvme_user_cmd(ns->ctrl, ns, (void __user *)arg);
666 	case NVME_IOCTL_SUBMIT_IO:
667 		return nvme_submit_io(ns, (void __user *)arg);
668 #ifdef CONFIG_BLK_DEV_NVME_SCSI
669 	case SG_GET_VERSION_NUM:
670 		return nvme_sg_get_version_num((void __user *)arg);
671 	case SG_IO:
672 		return nvme_sg_io(ns, (void __user *)arg);
673 #endif
674 	default:
675 		return -ENOTTY;
676 	}
677 }
678 
679 #ifdef CONFIG_COMPAT
680 static int nvme_compat_ioctl(struct block_device *bdev, fmode_t mode,
681 			unsigned int cmd, unsigned long arg)
682 {
683 	switch (cmd) {
684 	case SG_IO:
685 		return -ENOIOCTLCMD;
686 	}
687 	return nvme_ioctl(bdev, mode, cmd, arg);
688 }
689 #else
690 #define nvme_compat_ioctl	NULL
691 #endif
692 
693 static int nvme_open(struct block_device *bdev, fmode_t mode)
694 {
695 	return nvme_get_ns_from_disk(bdev->bd_disk) ? 0 : -ENXIO;
696 }
697 
698 static void nvme_release(struct gendisk *disk, fmode_t mode)
699 {
700 	struct nvme_ns *ns = disk->private_data;
701 
702 	module_put(ns->ctrl->ops->module);
703 	nvme_put_ns(ns);
704 }
705 
706 static int nvme_getgeo(struct block_device *bdev, struct hd_geometry *geo)
707 {
708 	/* some standard values */
709 	geo->heads = 1 << 6;
710 	geo->sectors = 1 << 5;
711 	geo->cylinders = get_capacity(bdev->bd_disk) >> 11;
712 	return 0;
713 }
714 
715 #ifdef CONFIG_BLK_DEV_INTEGRITY
716 static void nvme_init_integrity(struct nvme_ns *ns)
717 {
718 	struct blk_integrity integrity;
719 
720 	switch (ns->pi_type) {
721 	case NVME_NS_DPS_PI_TYPE3:
722 		integrity.profile = &t10_pi_type3_crc;
723 		break;
724 	case NVME_NS_DPS_PI_TYPE1:
725 	case NVME_NS_DPS_PI_TYPE2:
726 		integrity.profile = &t10_pi_type1_crc;
727 		break;
728 	default:
729 		integrity.profile = NULL;
730 		break;
731 	}
732 	integrity.tuple_size = ns->ms;
733 	blk_integrity_register(ns->disk, &integrity);
734 	blk_queue_max_integrity_segments(ns->queue, 1);
735 }
736 #else
737 static void nvme_init_integrity(struct nvme_ns *ns)
738 {
739 }
740 #endif /* CONFIG_BLK_DEV_INTEGRITY */
741 
742 static void nvme_config_discard(struct nvme_ns *ns)
743 {
744 	struct nvme_ctrl *ctrl = ns->ctrl;
745 	u32 logical_block_size = queue_logical_block_size(ns->queue);
746 
747 	if (ctrl->quirks & NVME_QUIRK_DISCARD_ZEROES)
748 		ns->queue->limits.discard_zeroes_data = 1;
749 	else
750 		ns->queue->limits.discard_zeroes_data = 0;
751 
752 	ns->queue->limits.discard_alignment = logical_block_size;
753 	ns->queue->limits.discard_granularity = logical_block_size;
754 	blk_queue_max_discard_sectors(ns->queue, 0xffffffff);
755 	queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, ns->queue);
756 }
757 
758 static int nvme_revalidate_disk(struct gendisk *disk)
759 {
760 	struct nvme_ns *ns = disk->private_data;
761 	struct nvme_id_ns *id;
762 	u8 lbaf, pi_type;
763 	u16 old_ms;
764 	unsigned short bs;
765 
766 	if (test_bit(NVME_NS_DEAD, &ns->flags)) {
767 		set_capacity(disk, 0);
768 		return -ENODEV;
769 	}
770 	if (nvme_identify_ns(ns->ctrl, ns->ns_id, &id)) {
771 		dev_warn(disk_to_dev(ns->disk), "%s: Identify failure\n",
772 				__func__);
773 		return -ENODEV;
774 	}
775 	if (id->ncap == 0) {
776 		kfree(id);
777 		return -ENODEV;
778 	}
779 
780 	if (nvme_nvm_ns_supported(ns, id) && ns->type != NVME_NS_LIGHTNVM) {
781 		if (nvme_nvm_register(ns->queue, disk->disk_name)) {
782 			dev_warn(disk_to_dev(ns->disk),
783 				"%s: LightNVM init failure\n", __func__);
784 			kfree(id);
785 			return -ENODEV;
786 		}
787 		ns->type = NVME_NS_LIGHTNVM;
788 	}
789 
790 	if (ns->ctrl->vs >= NVME_VS(1, 1))
791 		memcpy(ns->eui, id->eui64, sizeof(ns->eui));
792 	if (ns->ctrl->vs >= NVME_VS(1, 2))
793 		memcpy(ns->uuid, id->nguid, sizeof(ns->uuid));
794 
795 	old_ms = ns->ms;
796 	lbaf = id->flbas & NVME_NS_FLBAS_LBA_MASK;
797 	ns->lba_shift = id->lbaf[lbaf].ds;
798 	ns->ms = le16_to_cpu(id->lbaf[lbaf].ms);
799 	ns->ext = ns->ms && (id->flbas & NVME_NS_FLBAS_META_EXT);
800 
801 	/*
802 	 * If identify namespace failed, use default 512 byte block size so
803 	 * block layer can use before failing read/write for 0 capacity.
804 	 */
805 	if (ns->lba_shift == 0)
806 		ns->lba_shift = 9;
807 	bs = 1 << ns->lba_shift;
808 	/* XXX: PI implementation requires metadata equal t10 pi tuple size */
809 	pi_type = ns->ms == sizeof(struct t10_pi_tuple) ?
810 					id->dps & NVME_NS_DPS_PI_MASK : 0;
811 
812 	blk_mq_freeze_queue(disk->queue);
813 	if (blk_get_integrity(disk) && (ns->pi_type != pi_type ||
814 				ns->ms != old_ms ||
815 				bs != queue_logical_block_size(disk->queue) ||
816 				(ns->ms && ns->ext)))
817 		blk_integrity_unregister(disk);
818 
819 	ns->pi_type = pi_type;
820 	blk_queue_logical_block_size(ns->queue, bs);
821 
822 	if (ns->ms && !blk_get_integrity(disk) && !ns->ext)
823 		nvme_init_integrity(ns);
824 	if (ns->ms && !(ns->ms == 8 && ns->pi_type) && !blk_get_integrity(disk))
825 		set_capacity(disk, 0);
826 	else
827 		set_capacity(disk, le64_to_cpup(&id->nsze) << (ns->lba_shift - 9));
828 
829 	if (ns->ctrl->oncs & NVME_CTRL_ONCS_DSM)
830 		nvme_config_discard(ns);
831 	blk_mq_unfreeze_queue(disk->queue);
832 
833 	kfree(id);
834 	return 0;
835 }
836 
837 static char nvme_pr_type(enum pr_type type)
838 {
839 	switch (type) {
840 	case PR_WRITE_EXCLUSIVE:
841 		return 1;
842 	case PR_EXCLUSIVE_ACCESS:
843 		return 2;
844 	case PR_WRITE_EXCLUSIVE_REG_ONLY:
845 		return 3;
846 	case PR_EXCLUSIVE_ACCESS_REG_ONLY:
847 		return 4;
848 	case PR_WRITE_EXCLUSIVE_ALL_REGS:
849 		return 5;
850 	case PR_EXCLUSIVE_ACCESS_ALL_REGS:
851 		return 6;
852 	default:
853 		return 0;
854 	}
855 };
856 
857 static int nvme_pr_command(struct block_device *bdev, u32 cdw10,
858 				u64 key, u64 sa_key, u8 op)
859 {
860 	struct nvme_ns *ns = bdev->bd_disk->private_data;
861 	struct nvme_command c;
862 	u8 data[16] = { 0, };
863 
864 	put_unaligned_le64(key, &data[0]);
865 	put_unaligned_le64(sa_key, &data[8]);
866 
867 	memset(&c, 0, sizeof(c));
868 	c.common.opcode = op;
869 	c.common.nsid = cpu_to_le32(ns->ns_id);
870 	c.common.cdw10[0] = cpu_to_le32(cdw10);
871 
872 	return nvme_submit_sync_cmd(ns->queue, &c, data, 16);
873 }
874 
875 static int nvme_pr_register(struct block_device *bdev, u64 old,
876 		u64 new, unsigned flags)
877 {
878 	u32 cdw10;
879 
880 	if (flags & ~PR_FL_IGNORE_KEY)
881 		return -EOPNOTSUPP;
882 
883 	cdw10 = old ? 2 : 0;
884 	cdw10 |= (flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0;
885 	cdw10 |= (1 << 30) | (1 << 31); /* PTPL=1 */
886 	return nvme_pr_command(bdev, cdw10, old, new, nvme_cmd_resv_register);
887 }
888 
889 static int nvme_pr_reserve(struct block_device *bdev, u64 key,
890 		enum pr_type type, unsigned flags)
891 {
892 	u32 cdw10;
893 
894 	if (flags & ~PR_FL_IGNORE_KEY)
895 		return -EOPNOTSUPP;
896 
897 	cdw10 = nvme_pr_type(type) << 8;
898 	cdw10 |= ((flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0);
899 	return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_acquire);
900 }
901 
902 static int nvme_pr_preempt(struct block_device *bdev, u64 old, u64 new,
903 		enum pr_type type, bool abort)
904 {
905 	u32 cdw10 = nvme_pr_type(type) << 8 | abort ? 2 : 1;
906 	return nvme_pr_command(bdev, cdw10, old, new, nvme_cmd_resv_acquire);
907 }
908 
909 static int nvme_pr_clear(struct block_device *bdev, u64 key)
910 {
911 	u32 cdw10 = 1 | (key ? 1 << 3 : 0);
912 	return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_register);
913 }
914 
915 static int nvme_pr_release(struct block_device *bdev, u64 key, enum pr_type type)
916 {
917 	u32 cdw10 = nvme_pr_type(type) << 8 | key ? 1 << 3 : 0;
918 	return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_release);
919 }
920 
921 static const struct pr_ops nvme_pr_ops = {
922 	.pr_register	= nvme_pr_register,
923 	.pr_reserve	= nvme_pr_reserve,
924 	.pr_release	= nvme_pr_release,
925 	.pr_preempt	= nvme_pr_preempt,
926 	.pr_clear	= nvme_pr_clear,
927 };
928 
929 static const struct block_device_operations nvme_fops = {
930 	.owner		= THIS_MODULE,
931 	.ioctl		= nvme_ioctl,
932 	.compat_ioctl	= nvme_compat_ioctl,
933 	.open		= nvme_open,
934 	.release	= nvme_release,
935 	.getgeo		= nvme_getgeo,
936 	.revalidate_disk= nvme_revalidate_disk,
937 	.pr_ops		= &nvme_pr_ops,
938 };
939 
940 static int nvme_wait_ready(struct nvme_ctrl *ctrl, u64 cap, bool enabled)
941 {
942 	unsigned long timeout =
943 		((NVME_CAP_TIMEOUT(cap) + 1) * HZ / 2) + jiffies;
944 	u32 csts, bit = enabled ? NVME_CSTS_RDY : 0;
945 	int ret;
946 
947 	while ((ret = ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &csts)) == 0) {
948 		if ((csts & NVME_CSTS_RDY) == bit)
949 			break;
950 
951 		msleep(100);
952 		if (fatal_signal_pending(current))
953 			return -EINTR;
954 		if (time_after(jiffies, timeout)) {
955 			dev_err(ctrl->device,
956 				"Device not ready; aborting %s\n", enabled ?
957 						"initialisation" : "reset");
958 			return -ENODEV;
959 		}
960 	}
961 
962 	return ret;
963 }
964 
965 /*
966  * If the device has been passed off to us in an enabled state, just clear
967  * the enabled bit.  The spec says we should set the 'shutdown notification
968  * bits', but doing so may cause the device to complete commands to the
969  * admin queue ... and we don't know what memory that might be pointing at!
970  */
971 int nvme_disable_ctrl(struct nvme_ctrl *ctrl, u64 cap)
972 {
973 	int ret;
974 
975 	ctrl->ctrl_config &= ~NVME_CC_SHN_MASK;
976 	ctrl->ctrl_config &= ~NVME_CC_ENABLE;
977 
978 	ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
979 	if (ret)
980 		return ret;
981 	return nvme_wait_ready(ctrl, cap, false);
982 }
983 EXPORT_SYMBOL_GPL(nvme_disable_ctrl);
984 
985 int nvme_enable_ctrl(struct nvme_ctrl *ctrl, u64 cap)
986 {
987 	/*
988 	 * Default to a 4K page size, with the intention to update this
989 	 * path in the future to accomodate architectures with differing
990 	 * kernel and IO page sizes.
991 	 */
992 	unsigned dev_page_min = NVME_CAP_MPSMIN(cap) + 12, page_shift = 12;
993 	int ret;
994 
995 	if (page_shift < dev_page_min) {
996 		dev_err(ctrl->device,
997 			"Minimum device page size %u too large for host (%u)\n",
998 			1 << dev_page_min, 1 << page_shift);
999 		return -ENODEV;
1000 	}
1001 
1002 	ctrl->page_size = 1 << page_shift;
1003 
1004 	ctrl->ctrl_config = NVME_CC_CSS_NVM;
1005 	ctrl->ctrl_config |= (page_shift - 12) << NVME_CC_MPS_SHIFT;
1006 	ctrl->ctrl_config |= NVME_CC_ARB_RR | NVME_CC_SHN_NONE;
1007 	ctrl->ctrl_config |= NVME_CC_IOSQES | NVME_CC_IOCQES;
1008 	ctrl->ctrl_config |= NVME_CC_ENABLE;
1009 
1010 	ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
1011 	if (ret)
1012 		return ret;
1013 	return nvme_wait_ready(ctrl, cap, true);
1014 }
1015 EXPORT_SYMBOL_GPL(nvme_enable_ctrl);
1016 
1017 int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl)
1018 {
1019 	unsigned long timeout = SHUTDOWN_TIMEOUT + jiffies;
1020 	u32 csts;
1021 	int ret;
1022 
1023 	ctrl->ctrl_config &= ~NVME_CC_SHN_MASK;
1024 	ctrl->ctrl_config |= NVME_CC_SHN_NORMAL;
1025 
1026 	ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
1027 	if (ret)
1028 		return ret;
1029 
1030 	while ((ret = ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &csts)) == 0) {
1031 		if ((csts & NVME_CSTS_SHST_MASK) == NVME_CSTS_SHST_CMPLT)
1032 			break;
1033 
1034 		msleep(100);
1035 		if (fatal_signal_pending(current))
1036 			return -EINTR;
1037 		if (time_after(jiffies, timeout)) {
1038 			dev_err(ctrl->device,
1039 				"Device shutdown incomplete; abort shutdown\n");
1040 			return -ENODEV;
1041 		}
1042 	}
1043 
1044 	return ret;
1045 }
1046 EXPORT_SYMBOL_GPL(nvme_shutdown_ctrl);
1047 
1048 static void nvme_set_queue_limits(struct nvme_ctrl *ctrl,
1049 		struct request_queue *q)
1050 {
1051 	bool vwc = false;
1052 
1053 	if (ctrl->max_hw_sectors) {
1054 		u32 max_segments =
1055 			(ctrl->max_hw_sectors / (ctrl->page_size >> 9)) + 1;
1056 
1057 		blk_queue_max_hw_sectors(q, ctrl->max_hw_sectors);
1058 		blk_queue_max_segments(q, min_t(u32, max_segments, USHRT_MAX));
1059 	}
1060 	if (ctrl->stripe_size)
1061 		blk_queue_chunk_sectors(q, ctrl->stripe_size >> 9);
1062 	blk_queue_virt_boundary(q, ctrl->page_size - 1);
1063 	if (ctrl->vwc & NVME_CTRL_VWC_PRESENT)
1064 		vwc = true;
1065 	blk_queue_write_cache(q, vwc, vwc);
1066 }
1067 
1068 /*
1069  * Initialize the cached copies of the Identify data and various controller
1070  * register in our nvme_ctrl structure.  This should be called as soon as
1071  * the admin queue is fully up and running.
1072  */
1073 int nvme_init_identify(struct nvme_ctrl *ctrl)
1074 {
1075 	struct nvme_id_ctrl *id;
1076 	u64 cap;
1077 	int ret, page_shift;
1078 
1079 	ret = ctrl->ops->reg_read32(ctrl, NVME_REG_VS, &ctrl->vs);
1080 	if (ret) {
1081 		dev_err(ctrl->device, "Reading VS failed (%d)\n", ret);
1082 		return ret;
1083 	}
1084 
1085 	ret = ctrl->ops->reg_read64(ctrl, NVME_REG_CAP, &cap);
1086 	if (ret) {
1087 		dev_err(ctrl->device, "Reading CAP failed (%d)\n", ret);
1088 		return ret;
1089 	}
1090 	page_shift = NVME_CAP_MPSMIN(cap) + 12;
1091 
1092 	if (ctrl->vs >= NVME_VS(1, 1))
1093 		ctrl->subsystem = NVME_CAP_NSSRC(cap);
1094 
1095 	ret = nvme_identify_ctrl(ctrl, &id);
1096 	if (ret) {
1097 		dev_err(ctrl->device, "Identify Controller failed (%d)\n", ret);
1098 		return -EIO;
1099 	}
1100 
1101 	ctrl->vid = le16_to_cpu(id->vid);
1102 	ctrl->oncs = le16_to_cpup(&id->oncs);
1103 	atomic_set(&ctrl->abort_limit, id->acl + 1);
1104 	ctrl->vwc = id->vwc;
1105 	ctrl->cntlid = le16_to_cpup(&id->cntlid);
1106 	memcpy(ctrl->serial, id->sn, sizeof(id->sn));
1107 	memcpy(ctrl->model, id->mn, sizeof(id->mn));
1108 	memcpy(ctrl->firmware_rev, id->fr, sizeof(id->fr));
1109 	if (id->mdts)
1110 		ctrl->max_hw_sectors = 1 << (id->mdts + page_shift - 9);
1111 	else
1112 		ctrl->max_hw_sectors = UINT_MAX;
1113 
1114 	if ((ctrl->quirks & NVME_QUIRK_STRIPE_SIZE) && id->vs[3]) {
1115 		unsigned int max_hw_sectors;
1116 
1117 		ctrl->stripe_size = 1 << (id->vs[3] + page_shift);
1118 		max_hw_sectors = ctrl->stripe_size >> (page_shift - 9);
1119 		if (ctrl->max_hw_sectors) {
1120 			ctrl->max_hw_sectors = min(max_hw_sectors,
1121 							ctrl->max_hw_sectors);
1122 		} else {
1123 			ctrl->max_hw_sectors = max_hw_sectors;
1124 		}
1125 	}
1126 
1127 	nvme_set_queue_limits(ctrl, ctrl->admin_q);
1128 
1129 	kfree(id);
1130 	return 0;
1131 }
1132 EXPORT_SYMBOL_GPL(nvme_init_identify);
1133 
1134 static int nvme_dev_open(struct inode *inode, struct file *file)
1135 {
1136 	struct nvme_ctrl *ctrl;
1137 	int instance = iminor(inode);
1138 	int ret = -ENODEV;
1139 
1140 	spin_lock(&dev_list_lock);
1141 	list_for_each_entry(ctrl, &nvme_ctrl_list, node) {
1142 		if (ctrl->instance != instance)
1143 			continue;
1144 
1145 		if (!ctrl->admin_q) {
1146 			ret = -EWOULDBLOCK;
1147 			break;
1148 		}
1149 		if (!kref_get_unless_zero(&ctrl->kref))
1150 			break;
1151 		file->private_data = ctrl;
1152 		ret = 0;
1153 		break;
1154 	}
1155 	spin_unlock(&dev_list_lock);
1156 
1157 	return ret;
1158 }
1159 
1160 static int nvme_dev_release(struct inode *inode, struct file *file)
1161 {
1162 	nvme_put_ctrl(file->private_data);
1163 	return 0;
1164 }
1165 
1166 static int nvme_dev_user_cmd(struct nvme_ctrl *ctrl, void __user *argp)
1167 {
1168 	struct nvme_ns *ns;
1169 	int ret;
1170 
1171 	mutex_lock(&ctrl->namespaces_mutex);
1172 	if (list_empty(&ctrl->namespaces)) {
1173 		ret = -ENOTTY;
1174 		goto out_unlock;
1175 	}
1176 
1177 	ns = list_first_entry(&ctrl->namespaces, struct nvme_ns, list);
1178 	if (ns != list_last_entry(&ctrl->namespaces, struct nvme_ns, list)) {
1179 		dev_warn(ctrl->device,
1180 			"NVME_IOCTL_IO_CMD not supported when multiple namespaces present!\n");
1181 		ret = -EINVAL;
1182 		goto out_unlock;
1183 	}
1184 
1185 	dev_warn(ctrl->device,
1186 		"using deprecated NVME_IOCTL_IO_CMD ioctl on the char device!\n");
1187 	kref_get(&ns->kref);
1188 	mutex_unlock(&ctrl->namespaces_mutex);
1189 
1190 	ret = nvme_user_cmd(ctrl, ns, argp);
1191 	nvme_put_ns(ns);
1192 	return ret;
1193 
1194 out_unlock:
1195 	mutex_unlock(&ctrl->namespaces_mutex);
1196 	return ret;
1197 }
1198 
1199 static long nvme_dev_ioctl(struct file *file, unsigned int cmd,
1200 		unsigned long arg)
1201 {
1202 	struct nvme_ctrl *ctrl = file->private_data;
1203 	void __user *argp = (void __user *)arg;
1204 
1205 	switch (cmd) {
1206 	case NVME_IOCTL_ADMIN_CMD:
1207 		return nvme_user_cmd(ctrl, NULL, argp);
1208 	case NVME_IOCTL_IO_CMD:
1209 		return nvme_dev_user_cmd(ctrl, argp);
1210 	case NVME_IOCTL_RESET:
1211 		dev_warn(ctrl->device, "resetting controller\n");
1212 		return ctrl->ops->reset_ctrl(ctrl);
1213 	case NVME_IOCTL_SUBSYS_RESET:
1214 		return nvme_reset_subsystem(ctrl);
1215 	default:
1216 		return -ENOTTY;
1217 	}
1218 }
1219 
1220 static const struct file_operations nvme_dev_fops = {
1221 	.owner		= THIS_MODULE,
1222 	.open		= nvme_dev_open,
1223 	.release	= nvme_dev_release,
1224 	.unlocked_ioctl	= nvme_dev_ioctl,
1225 	.compat_ioctl	= nvme_dev_ioctl,
1226 };
1227 
1228 static ssize_t nvme_sysfs_reset(struct device *dev,
1229 				struct device_attribute *attr, const char *buf,
1230 				size_t count)
1231 {
1232 	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
1233 	int ret;
1234 
1235 	ret = ctrl->ops->reset_ctrl(ctrl);
1236 	if (ret < 0)
1237 		return ret;
1238 	return count;
1239 }
1240 static DEVICE_ATTR(reset_controller, S_IWUSR, NULL, nvme_sysfs_reset);
1241 
1242 static ssize_t wwid_show(struct device *dev, struct device_attribute *attr,
1243 								char *buf)
1244 {
1245 	struct nvme_ns *ns = dev_to_disk(dev)->private_data;
1246 	struct nvme_ctrl *ctrl = ns->ctrl;
1247 	int serial_len = sizeof(ctrl->serial);
1248 	int model_len = sizeof(ctrl->model);
1249 
1250 	if (memchr_inv(ns->uuid, 0, sizeof(ns->uuid)))
1251 		return sprintf(buf, "eui.%16phN\n", ns->uuid);
1252 
1253 	if (memchr_inv(ns->eui, 0, sizeof(ns->eui)))
1254 		return sprintf(buf, "eui.%8phN\n", ns->eui);
1255 
1256 	while (ctrl->serial[serial_len - 1] == ' ')
1257 		serial_len--;
1258 	while (ctrl->model[model_len - 1] == ' ')
1259 		model_len--;
1260 
1261 	return sprintf(buf, "nvme.%04x-%*phN-%*phN-%08x\n", ctrl->vid,
1262 		serial_len, ctrl->serial, model_len, ctrl->model, ns->ns_id);
1263 }
1264 static DEVICE_ATTR(wwid, S_IRUGO, wwid_show, NULL);
1265 
1266 static ssize_t uuid_show(struct device *dev, struct device_attribute *attr,
1267 								char *buf)
1268 {
1269 	struct nvme_ns *ns = dev_to_disk(dev)->private_data;
1270 	return sprintf(buf, "%pU\n", ns->uuid);
1271 }
1272 static DEVICE_ATTR(uuid, S_IRUGO, uuid_show, NULL);
1273 
1274 static ssize_t eui_show(struct device *dev, struct device_attribute *attr,
1275 								char *buf)
1276 {
1277 	struct nvme_ns *ns = dev_to_disk(dev)->private_data;
1278 	return sprintf(buf, "%8phd\n", ns->eui);
1279 }
1280 static DEVICE_ATTR(eui, S_IRUGO, eui_show, NULL);
1281 
1282 static ssize_t nsid_show(struct device *dev, struct device_attribute *attr,
1283 								char *buf)
1284 {
1285 	struct nvme_ns *ns = dev_to_disk(dev)->private_data;
1286 	return sprintf(buf, "%d\n", ns->ns_id);
1287 }
1288 static DEVICE_ATTR(nsid, S_IRUGO, nsid_show, NULL);
1289 
1290 static struct attribute *nvme_ns_attrs[] = {
1291 	&dev_attr_wwid.attr,
1292 	&dev_attr_uuid.attr,
1293 	&dev_attr_eui.attr,
1294 	&dev_attr_nsid.attr,
1295 	NULL,
1296 };
1297 
1298 static umode_t nvme_attrs_are_visible(struct kobject *kobj,
1299 		struct attribute *a, int n)
1300 {
1301 	struct device *dev = container_of(kobj, struct device, kobj);
1302 	struct nvme_ns *ns = dev_to_disk(dev)->private_data;
1303 
1304 	if (a == &dev_attr_uuid.attr) {
1305 		if (!memchr_inv(ns->uuid, 0, sizeof(ns->uuid)))
1306 			return 0;
1307 	}
1308 	if (a == &dev_attr_eui.attr) {
1309 		if (!memchr_inv(ns->eui, 0, sizeof(ns->eui)))
1310 			return 0;
1311 	}
1312 	return a->mode;
1313 }
1314 
1315 static const struct attribute_group nvme_ns_attr_group = {
1316 	.attrs		= nvme_ns_attrs,
1317 	.is_visible	= nvme_attrs_are_visible,
1318 };
1319 
1320 #define nvme_show_str_function(field)						\
1321 static ssize_t  field##_show(struct device *dev,				\
1322 			    struct device_attribute *attr, char *buf)		\
1323 {										\
1324         struct nvme_ctrl *ctrl = dev_get_drvdata(dev);				\
1325         return sprintf(buf, "%.*s\n", (int)sizeof(ctrl->field), ctrl->field);	\
1326 }										\
1327 static DEVICE_ATTR(field, S_IRUGO, field##_show, NULL);
1328 
1329 #define nvme_show_int_function(field)						\
1330 static ssize_t  field##_show(struct device *dev,				\
1331 			    struct device_attribute *attr, char *buf)		\
1332 {										\
1333         struct nvme_ctrl *ctrl = dev_get_drvdata(dev);				\
1334         return sprintf(buf, "%d\n", ctrl->field);	\
1335 }										\
1336 static DEVICE_ATTR(field, S_IRUGO, field##_show, NULL);
1337 
1338 nvme_show_str_function(model);
1339 nvme_show_str_function(serial);
1340 nvme_show_str_function(firmware_rev);
1341 nvme_show_int_function(cntlid);
1342 
1343 static struct attribute *nvme_dev_attrs[] = {
1344 	&dev_attr_reset_controller.attr,
1345 	&dev_attr_model.attr,
1346 	&dev_attr_serial.attr,
1347 	&dev_attr_firmware_rev.attr,
1348 	&dev_attr_cntlid.attr,
1349 	NULL
1350 };
1351 
1352 static struct attribute_group nvme_dev_attrs_group = {
1353 	.attrs = nvme_dev_attrs,
1354 };
1355 
1356 static const struct attribute_group *nvme_dev_attr_groups[] = {
1357 	&nvme_dev_attrs_group,
1358 	NULL,
1359 };
1360 
1361 static int ns_cmp(void *priv, struct list_head *a, struct list_head *b)
1362 {
1363 	struct nvme_ns *nsa = container_of(a, struct nvme_ns, list);
1364 	struct nvme_ns *nsb = container_of(b, struct nvme_ns, list);
1365 
1366 	return nsa->ns_id - nsb->ns_id;
1367 }
1368 
1369 static struct nvme_ns *nvme_find_ns(struct nvme_ctrl *ctrl, unsigned nsid)
1370 {
1371 	struct nvme_ns *ns;
1372 
1373 	lockdep_assert_held(&ctrl->namespaces_mutex);
1374 
1375 	list_for_each_entry(ns, &ctrl->namespaces, list) {
1376 		if (ns->ns_id == nsid)
1377 			return ns;
1378 		if (ns->ns_id > nsid)
1379 			break;
1380 	}
1381 	return NULL;
1382 }
1383 
1384 static void nvme_alloc_ns(struct nvme_ctrl *ctrl, unsigned nsid)
1385 {
1386 	struct nvme_ns *ns;
1387 	struct gendisk *disk;
1388 	int node = dev_to_node(ctrl->dev);
1389 
1390 	lockdep_assert_held(&ctrl->namespaces_mutex);
1391 
1392 	ns = kzalloc_node(sizeof(*ns), GFP_KERNEL, node);
1393 	if (!ns)
1394 		return;
1395 
1396 	ns->instance = ida_simple_get(&ctrl->ns_ida, 1, 0, GFP_KERNEL);
1397 	if (ns->instance < 0)
1398 		goto out_free_ns;
1399 
1400 	ns->queue = blk_mq_init_queue(ctrl->tagset);
1401 	if (IS_ERR(ns->queue))
1402 		goto out_release_instance;
1403 	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, ns->queue);
1404 	ns->queue->queuedata = ns;
1405 	ns->ctrl = ctrl;
1406 
1407 	disk = alloc_disk_node(0, node);
1408 	if (!disk)
1409 		goto out_free_queue;
1410 
1411 	kref_init(&ns->kref);
1412 	ns->ns_id = nsid;
1413 	ns->disk = disk;
1414 	ns->lba_shift = 9; /* set to a default value for 512 until disk is validated */
1415 
1416 
1417 	blk_queue_logical_block_size(ns->queue, 1 << ns->lba_shift);
1418 	nvme_set_queue_limits(ctrl, ns->queue);
1419 
1420 	disk->major = nvme_major;
1421 	disk->first_minor = 0;
1422 	disk->fops = &nvme_fops;
1423 	disk->private_data = ns;
1424 	disk->queue = ns->queue;
1425 	disk->driverfs_dev = ctrl->device;
1426 	disk->flags = GENHD_FL_EXT_DEVT;
1427 	sprintf(disk->disk_name, "nvme%dn%d", ctrl->instance, ns->instance);
1428 
1429 	if (nvme_revalidate_disk(ns->disk))
1430 		goto out_free_disk;
1431 
1432 	list_add_tail_rcu(&ns->list, &ctrl->namespaces);
1433 	kref_get(&ctrl->kref);
1434 	if (ns->type == NVME_NS_LIGHTNVM)
1435 		return;
1436 
1437 	add_disk(ns->disk);
1438 	if (sysfs_create_group(&disk_to_dev(ns->disk)->kobj,
1439 					&nvme_ns_attr_group))
1440 		pr_warn("%s: failed to create sysfs group for identification\n",
1441 			ns->disk->disk_name);
1442 	return;
1443  out_free_disk:
1444 	kfree(disk);
1445  out_free_queue:
1446 	blk_cleanup_queue(ns->queue);
1447  out_release_instance:
1448 	ida_simple_remove(&ctrl->ns_ida, ns->instance);
1449  out_free_ns:
1450 	kfree(ns);
1451 }
1452 
1453 static void nvme_ns_remove(struct nvme_ns *ns)
1454 {
1455 	lockdep_assert_held(&ns->ctrl->namespaces_mutex);
1456 
1457 	if (test_and_set_bit(NVME_NS_REMOVING, &ns->flags))
1458 		return;
1459 
1460 	if (ns->disk->flags & GENHD_FL_UP) {
1461 		if (blk_get_integrity(ns->disk))
1462 			blk_integrity_unregister(ns->disk);
1463 		sysfs_remove_group(&disk_to_dev(ns->disk)->kobj,
1464 					&nvme_ns_attr_group);
1465 		del_gendisk(ns->disk);
1466 		blk_mq_abort_requeue_list(ns->queue);
1467 		blk_cleanup_queue(ns->queue);
1468 	}
1469 	list_del_init(&ns->list);
1470 	synchronize_rcu();
1471 	nvme_put_ns(ns);
1472 }
1473 
1474 static void nvme_validate_ns(struct nvme_ctrl *ctrl, unsigned nsid)
1475 {
1476 	struct nvme_ns *ns;
1477 
1478 	ns = nvme_find_ns(ctrl, nsid);
1479 	if (ns) {
1480 		if (revalidate_disk(ns->disk))
1481 			nvme_ns_remove(ns);
1482 	} else
1483 		nvme_alloc_ns(ctrl, nsid);
1484 }
1485 
1486 static int nvme_scan_ns_list(struct nvme_ctrl *ctrl, unsigned nn)
1487 {
1488 	struct nvme_ns *ns;
1489 	__le32 *ns_list;
1490 	unsigned i, j, nsid, prev = 0, num_lists = DIV_ROUND_UP(nn, 1024);
1491 	int ret = 0;
1492 
1493 	ns_list = kzalloc(0x1000, GFP_KERNEL);
1494 	if (!ns_list)
1495 		return -ENOMEM;
1496 
1497 	for (i = 0; i < num_lists; i++) {
1498 		ret = nvme_identify_ns_list(ctrl, prev, ns_list);
1499 		if (ret)
1500 			goto out;
1501 
1502 		for (j = 0; j < min(nn, 1024U); j++) {
1503 			nsid = le32_to_cpu(ns_list[j]);
1504 			if (!nsid)
1505 				goto out;
1506 
1507 			nvme_validate_ns(ctrl, nsid);
1508 
1509 			while (++prev < nsid) {
1510 				ns = nvme_find_ns(ctrl, prev);
1511 				if (ns)
1512 					nvme_ns_remove(ns);
1513 			}
1514 		}
1515 		nn -= j;
1516 	}
1517  out:
1518 	kfree(ns_list);
1519 	return ret;
1520 }
1521 
1522 static void nvme_scan_ns_sequential(struct nvme_ctrl *ctrl, unsigned nn)
1523 {
1524 	struct nvme_ns *ns, *next;
1525 	unsigned i;
1526 
1527 	lockdep_assert_held(&ctrl->namespaces_mutex);
1528 
1529 	for (i = 1; i <= nn; i++)
1530 		nvme_validate_ns(ctrl, i);
1531 
1532 	list_for_each_entry_safe(ns, next, &ctrl->namespaces, list) {
1533 		if (ns->ns_id > nn)
1534 			nvme_ns_remove(ns);
1535 	}
1536 }
1537 
1538 static void nvme_scan_work(struct work_struct *work)
1539 {
1540 	struct nvme_ctrl *ctrl =
1541 		container_of(work, struct nvme_ctrl, scan_work);
1542 	struct nvme_id_ctrl *id;
1543 	unsigned nn;
1544 
1545 	if (ctrl->state != NVME_CTRL_LIVE)
1546 		return;
1547 
1548 	if (nvme_identify_ctrl(ctrl, &id))
1549 		return;
1550 
1551 	mutex_lock(&ctrl->namespaces_mutex);
1552 	nn = le32_to_cpu(id->nn);
1553 	if (ctrl->vs >= NVME_VS(1, 1) &&
1554 	    !(ctrl->quirks & NVME_QUIRK_IDENTIFY_CNS)) {
1555 		if (!nvme_scan_ns_list(ctrl, nn))
1556 			goto done;
1557 	}
1558 	nvme_scan_ns_sequential(ctrl, nn);
1559  done:
1560 	list_sort(NULL, &ctrl->namespaces, ns_cmp);
1561 	mutex_unlock(&ctrl->namespaces_mutex);
1562 	kfree(id);
1563 
1564 	if (ctrl->ops->post_scan)
1565 		ctrl->ops->post_scan(ctrl);
1566 }
1567 
1568 void nvme_queue_scan(struct nvme_ctrl *ctrl)
1569 {
1570 	/*
1571 	 * Do not queue new scan work when a controller is reset during
1572 	 * removal.
1573 	 */
1574 	if (ctrl->state == NVME_CTRL_LIVE)
1575 		schedule_work(&ctrl->scan_work);
1576 }
1577 EXPORT_SYMBOL_GPL(nvme_queue_scan);
1578 
1579 void nvme_remove_namespaces(struct nvme_ctrl *ctrl)
1580 {
1581 	struct nvme_ns *ns, *next;
1582 
1583 	mutex_lock(&ctrl->namespaces_mutex);
1584 	list_for_each_entry_safe(ns, next, &ctrl->namespaces, list)
1585 		nvme_ns_remove(ns);
1586 	mutex_unlock(&ctrl->namespaces_mutex);
1587 }
1588 EXPORT_SYMBOL_GPL(nvme_remove_namespaces);
1589 
1590 static void nvme_async_event_work(struct work_struct *work)
1591 {
1592 	struct nvme_ctrl *ctrl =
1593 		container_of(work, struct nvme_ctrl, async_event_work);
1594 
1595 	spin_lock_irq(&ctrl->lock);
1596 	while (ctrl->event_limit > 0) {
1597 		int aer_idx = --ctrl->event_limit;
1598 
1599 		spin_unlock_irq(&ctrl->lock);
1600 		ctrl->ops->submit_async_event(ctrl, aer_idx);
1601 		spin_lock_irq(&ctrl->lock);
1602 	}
1603 	spin_unlock_irq(&ctrl->lock);
1604 }
1605 
1606 void nvme_complete_async_event(struct nvme_ctrl *ctrl,
1607 		struct nvme_completion *cqe)
1608 {
1609 	u16 status = le16_to_cpu(cqe->status) >> 1;
1610 	u32 result = le32_to_cpu(cqe->result);
1611 
1612 	if (status == NVME_SC_SUCCESS || status == NVME_SC_ABORT_REQ) {
1613 		++ctrl->event_limit;
1614 		schedule_work(&ctrl->async_event_work);
1615 	}
1616 
1617 	if (status != NVME_SC_SUCCESS)
1618 		return;
1619 
1620 	switch (result & 0xff07) {
1621 	case NVME_AER_NOTICE_NS_CHANGED:
1622 		dev_info(ctrl->device, "rescanning\n");
1623 		nvme_queue_scan(ctrl);
1624 		break;
1625 	default:
1626 		dev_warn(ctrl->device, "async event result %08x\n", result);
1627 	}
1628 }
1629 EXPORT_SYMBOL_GPL(nvme_complete_async_event);
1630 
1631 void nvme_queue_async_events(struct nvme_ctrl *ctrl)
1632 {
1633 	ctrl->event_limit = NVME_NR_AERS;
1634 	schedule_work(&ctrl->async_event_work);
1635 }
1636 EXPORT_SYMBOL_GPL(nvme_queue_async_events);
1637 
1638 static DEFINE_IDA(nvme_instance_ida);
1639 
1640 static int nvme_set_instance(struct nvme_ctrl *ctrl)
1641 {
1642 	int instance, error;
1643 
1644 	do {
1645 		if (!ida_pre_get(&nvme_instance_ida, GFP_KERNEL))
1646 			return -ENODEV;
1647 
1648 		spin_lock(&dev_list_lock);
1649 		error = ida_get_new(&nvme_instance_ida, &instance);
1650 		spin_unlock(&dev_list_lock);
1651 	} while (error == -EAGAIN);
1652 
1653 	if (error)
1654 		return -ENODEV;
1655 
1656 	ctrl->instance = instance;
1657 	return 0;
1658 }
1659 
1660 static void nvme_release_instance(struct nvme_ctrl *ctrl)
1661 {
1662 	spin_lock(&dev_list_lock);
1663 	ida_remove(&nvme_instance_ida, ctrl->instance);
1664 	spin_unlock(&dev_list_lock);
1665 }
1666 
1667 void nvme_uninit_ctrl(struct nvme_ctrl *ctrl)
1668 {
1669 	flush_work(&ctrl->async_event_work);
1670 	flush_work(&ctrl->scan_work);
1671 	nvme_remove_namespaces(ctrl);
1672 
1673 	device_destroy(nvme_class, MKDEV(nvme_char_major, ctrl->instance));
1674 
1675 	spin_lock(&dev_list_lock);
1676 	list_del(&ctrl->node);
1677 	spin_unlock(&dev_list_lock);
1678 }
1679 EXPORT_SYMBOL_GPL(nvme_uninit_ctrl);
1680 
1681 static void nvme_free_ctrl(struct kref *kref)
1682 {
1683 	struct nvme_ctrl *ctrl = container_of(kref, struct nvme_ctrl, kref);
1684 
1685 	put_device(ctrl->device);
1686 	nvme_release_instance(ctrl);
1687 	ida_destroy(&ctrl->ns_ida);
1688 
1689 	ctrl->ops->free_ctrl(ctrl);
1690 }
1691 
1692 void nvme_put_ctrl(struct nvme_ctrl *ctrl)
1693 {
1694 	kref_put(&ctrl->kref, nvme_free_ctrl);
1695 }
1696 EXPORT_SYMBOL_GPL(nvme_put_ctrl);
1697 
1698 /*
1699  * Initialize a NVMe controller structures.  This needs to be called during
1700  * earliest initialization so that we have the initialized structured around
1701  * during probing.
1702  */
1703 int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
1704 		const struct nvme_ctrl_ops *ops, unsigned long quirks)
1705 {
1706 	int ret;
1707 
1708 	ctrl->state = NVME_CTRL_NEW;
1709 	spin_lock_init(&ctrl->lock);
1710 	INIT_LIST_HEAD(&ctrl->namespaces);
1711 	mutex_init(&ctrl->namespaces_mutex);
1712 	kref_init(&ctrl->kref);
1713 	ctrl->dev = dev;
1714 	ctrl->ops = ops;
1715 	ctrl->quirks = quirks;
1716 	INIT_WORK(&ctrl->scan_work, nvme_scan_work);
1717 	INIT_WORK(&ctrl->async_event_work, nvme_async_event_work);
1718 
1719 	ret = nvme_set_instance(ctrl);
1720 	if (ret)
1721 		goto out;
1722 
1723 	ctrl->device = device_create_with_groups(nvme_class, ctrl->dev,
1724 				MKDEV(nvme_char_major, ctrl->instance),
1725 				ctrl, nvme_dev_attr_groups,
1726 				"nvme%d", ctrl->instance);
1727 	if (IS_ERR(ctrl->device)) {
1728 		ret = PTR_ERR(ctrl->device);
1729 		goto out_release_instance;
1730 	}
1731 	get_device(ctrl->device);
1732 	ida_init(&ctrl->ns_ida);
1733 
1734 	spin_lock(&dev_list_lock);
1735 	list_add_tail(&ctrl->node, &nvme_ctrl_list);
1736 	spin_unlock(&dev_list_lock);
1737 
1738 	return 0;
1739 out_release_instance:
1740 	nvme_release_instance(ctrl);
1741 out:
1742 	return ret;
1743 }
1744 EXPORT_SYMBOL_GPL(nvme_init_ctrl);
1745 
1746 /**
1747  * nvme_kill_queues(): Ends all namespace queues
1748  * @ctrl: the dead controller that needs to end
1749  *
1750  * Call this function when the driver determines it is unable to get the
1751  * controller in a state capable of servicing IO.
1752  */
1753 void nvme_kill_queues(struct nvme_ctrl *ctrl)
1754 {
1755 	struct nvme_ns *ns;
1756 
1757 	rcu_read_lock();
1758 	list_for_each_entry_rcu(ns, &ctrl->namespaces, list) {
1759 		if (!kref_get_unless_zero(&ns->kref))
1760 			continue;
1761 
1762 		/*
1763 		 * Revalidating a dead namespace sets capacity to 0. This will
1764 		 * end buffered writers dirtying pages that can't be synced.
1765 		 */
1766 		if (!test_and_set_bit(NVME_NS_DEAD, &ns->flags))
1767 			revalidate_disk(ns->disk);
1768 
1769 		blk_set_queue_dying(ns->queue);
1770 		blk_mq_abort_requeue_list(ns->queue);
1771 		blk_mq_start_stopped_hw_queues(ns->queue, true);
1772 
1773 		nvme_put_ns(ns);
1774 	}
1775 	rcu_read_unlock();
1776 }
1777 EXPORT_SYMBOL_GPL(nvme_kill_queues);
1778 
1779 void nvme_stop_queues(struct nvme_ctrl *ctrl)
1780 {
1781 	struct nvme_ns *ns;
1782 
1783 	rcu_read_lock();
1784 	list_for_each_entry_rcu(ns, &ctrl->namespaces, list) {
1785 		spin_lock_irq(ns->queue->queue_lock);
1786 		queue_flag_set(QUEUE_FLAG_STOPPED, ns->queue);
1787 		spin_unlock_irq(ns->queue->queue_lock);
1788 
1789 		blk_mq_cancel_requeue_work(ns->queue);
1790 		blk_mq_stop_hw_queues(ns->queue);
1791 	}
1792 	rcu_read_unlock();
1793 }
1794 EXPORT_SYMBOL_GPL(nvme_stop_queues);
1795 
1796 void nvme_start_queues(struct nvme_ctrl *ctrl)
1797 {
1798 	struct nvme_ns *ns;
1799 
1800 	rcu_read_lock();
1801 	list_for_each_entry_rcu(ns, &ctrl->namespaces, list) {
1802 		queue_flag_clear_unlocked(QUEUE_FLAG_STOPPED, ns->queue);
1803 		blk_mq_start_stopped_hw_queues(ns->queue, true);
1804 		blk_mq_kick_requeue_list(ns->queue);
1805 	}
1806 	rcu_read_unlock();
1807 }
1808 EXPORT_SYMBOL_GPL(nvme_start_queues);
1809 
1810 int __init nvme_core_init(void)
1811 {
1812 	int result;
1813 
1814 	result = register_blkdev(nvme_major, "nvme");
1815 	if (result < 0)
1816 		return result;
1817 	else if (result > 0)
1818 		nvme_major = result;
1819 
1820 	result = __register_chrdev(nvme_char_major, 0, NVME_MINORS, "nvme",
1821 							&nvme_dev_fops);
1822 	if (result < 0)
1823 		goto unregister_blkdev;
1824 	else if (result > 0)
1825 		nvme_char_major = result;
1826 
1827 	nvme_class = class_create(THIS_MODULE, "nvme");
1828 	if (IS_ERR(nvme_class)) {
1829 		result = PTR_ERR(nvme_class);
1830 		goto unregister_chrdev;
1831 	}
1832 
1833 	return 0;
1834 
1835  unregister_chrdev:
1836 	__unregister_chrdev(nvme_char_major, 0, NVME_MINORS, "nvme");
1837  unregister_blkdev:
1838 	unregister_blkdev(nvme_major, "nvme");
1839 	return result;
1840 }
1841 
1842 void nvme_core_exit(void)
1843 {
1844 	class_destroy(nvme_class);
1845 	__unregister_chrdev(nvme_char_major, 0, NVME_MINORS, "nvme");
1846 	unregister_blkdev(nvme_major, "nvme");
1847 }
1848 
1849 MODULE_LICENSE("GPL");
1850 MODULE_VERSION("1.0");
1851 module_init(nvme_core_init);
1852 module_exit(nvme_core_exit);
1853