xref: /openbmc/linux/drivers/nvme/host/core.c (revision 7587eb18)
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 	case NVME_CTRL_DEAD:
99 		switch (old_state) {
100 		case NVME_CTRL_DELETING:
101 			changed = true;
102 			/* FALLTHRU */
103 		default:
104 			break;
105 		}
106 		break;
107 	default:
108 		break;
109 	}
110 	spin_unlock_irq(&ctrl->lock);
111 
112 	if (changed)
113 		ctrl->state = new_state;
114 
115 	return changed;
116 }
117 EXPORT_SYMBOL_GPL(nvme_change_ctrl_state);
118 
119 static void nvme_free_ns(struct kref *kref)
120 {
121 	struct nvme_ns *ns = container_of(kref, struct nvme_ns, kref);
122 
123 	if (ns->type == NVME_NS_LIGHTNVM)
124 		nvme_nvm_unregister(ns->queue, ns->disk->disk_name);
125 
126 	spin_lock(&dev_list_lock);
127 	ns->disk->private_data = NULL;
128 	spin_unlock(&dev_list_lock);
129 
130 	put_disk(ns->disk);
131 	ida_simple_remove(&ns->ctrl->ns_ida, ns->instance);
132 	nvme_put_ctrl(ns->ctrl);
133 	kfree(ns);
134 }
135 
136 static void nvme_put_ns(struct nvme_ns *ns)
137 {
138 	kref_put(&ns->kref, nvme_free_ns);
139 }
140 
141 static struct nvme_ns *nvme_get_ns_from_disk(struct gendisk *disk)
142 {
143 	struct nvme_ns *ns;
144 
145 	spin_lock(&dev_list_lock);
146 	ns = disk->private_data;
147 	if (ns) {
148 		if (!kref_get_unless_zero(&ns->kref))
149 			goto fail;
150 		if (!try_module_get(ns->ctrl->ops->module))
151 			goto fail_put_ns;
152 	}
153 	spin_unlock(&dev_list_lock);
154 
155 	return ns;
156 
157 fail_put_ns:
158 	kref_put(&ns->kref, nvme_free_ns);
159 fail:
160 	spin_unlock(&dev_list_lock);
161 	return NULL;
162 }
163 
164 void nvme_requeue_req(struct request *req)
165 {
166 	unsigned long flags;
167 
168 	blk_mq_requeue_request(req);
169 	spin_lock_irqsave(req->q->queue_lock, flags);
170 	if (!blk_queue_stopped(req->q))
171 		blk_mq_kick_requeue_list(req->q);
172 	spin_unlock_irqrestore(req->q->queue_lock, flags);
173 }
174 EXPORT_SYMBOL_GPL(nvme_requeue_req);
175 
176 struct request *nvme_alloc_request(struct request_queue *q,
177 		struct nvme_command *cmd, unsigned int flags)
178 {
179 	bool write = cmd->common.opcode & 1;
180 	struct request *req;
181 
182 	req = blk_mq_alloc_request(q, write, flags);
183 	if (IS_ERR(req))
184 		return req;
185 
186 	req->cmd_type = REQ_TYPE_DRV_PRIV;
187 	req->cmd_flags |= REQ_FAILFAST_DRIVER;
188 	req->__data_len = 0;
189 	req->__sector = (sector_t) -1;
190 	req->bio = req->biotail = NULL;
191 
192 	req->cmd = (unsigned char *)cmd;
193 	req->cmd_len = sizeof(struct nvme_command);
194 
195 	return req;
196 }
197 EXPORT_SYMBOL_GPL(nvme_alloc_request);
198 
199 static inline void nvme_setup_flush(struct nvme_ns *ns,
200 		struct nvme_command *cmnd)
201 {
202 	memset(cmnd, 0, sizeof(*cmnd));
203 	cmnd->common.opcode = nvme_cmd_flush;
204 	cmnd->common.nsid = cpu_to_le32(ns->ns_id);
205 }
206 
207 static inline int nvme_setup_discard(struct nvme_ns *ns, struct request *req,
208 		struct nvme_command *cmnd)
209 {
210 	struct nvme_dsm_range *range;
211 	struct page *page;
212 	int offset;
213 	unsigned int nr_bytes = blk_rq_bytes(req);
214 
215 	range = kmalloc(sizeof(*range), GFP_ATOMIC);
216 	if (!range)
217 		return BLK_MQ_RQ_QUEUE_BUSY;
218 
219 	range->cattr = cpu_to_le32(0);
220 	range->nlb = cpu_to_le32(nr_bytes >> ns->lba_shift);
221 	range->slba = cpu_to_le64(nvme_block_nr(ns, blk_rq_pos(req)));
222 
223 	memset(cmnd, 0, sizeof(*cmnd));
224 	cmnd->dsm.opcode = nvme_cmd_dsm;
225 	cmnd->dsm.nsid = cpu_to_le32(ns->ns_id);
226 	cmnd->dsm.nr = 0;
227 	cmnd->dsm.attributes = cpu_to_le32(NVME_DSMGMT_AD);
228 
229 	req->completion_data = range;
230 	page = virt_to_page(range);
231 	offset = offset_in_page(range);
232 	blk_add_request_payload(req, page, offset, sizeof(*range));
233 
234 	/*
235 	 * we set __data_len back to the size of the area to be discarded
236 	 * on disk. This allows us to report completion on the full amount
237 	 * of blocks described by the request.
238 	 */
239 	req->__data_len = nr_bytes;
240 
241 	return 0;
242 }
243 
244 static inline void nvme_setup_rw(struct nvme_ns *ns, struct request *req,
245 		struct nvme_command *cmnd)
246 {
247 	u16 control = 0;
248 	u32 dsmgmt = 0;
249 
250 	if (req->cmd_flags & REQ_FUA)
251 		control |= NVME_RW_FUA;
252 	if (req->cmd_flags & (REQ_FAILFAST_DEV | REQ_RAHEAD))
253 		control |= NVME_RW_LR;
254 
255 	if (req->cmd_flags & REQ_RAHEAD)
256 		dsmgmt |= NVME_RW_DSM_FREQ_PREFETCH;
257 
258 	memset(cmnd, 0, sizeof(*cmnd));
259 	cmnd->rw.opcode = (rq_data_dir(req) ? nvme_cmd_write : nvme_cmd_read);
260 	cmnd->rw.command_id = req->tag;
261 	cmnd->rw.nsid = cpu_to_le32(ns->ns_id);
262 	cmnd->rw.slba = cpu_to_le64(nvme_block_nr(ns, blk_rq_pos(req)));
263 	cmnd->rw.length = cpu_to_le16((blk_rq_bytes(req) >> ns->lba_shift) - 1);
264 
265 	if (ns->ms) {
266 		switch (ns->pi_type) {
267 		case NVME_NS_DPS_PI_TYPE3:
268 			control |= NVME_RW_PRINFO_PRCHK_GUARD;
269 			break;
270 		case NVME_NS_DPS_PI_TYPE1:
271 		case NVME_NS_DPS_PI_TYPE2:
272 			control |= NVME_RW_PRINFO_PRCHK_GUARD |
273 					NVME_RW_PRINFO_PRCHK_REF;
274 			cmnd->rw.reftag = cpu_to_le32(
275 					nvme_block_nr(ns, blk_rq_pos(req)));
276 			break;
277 		}
278 		if (!blk_integrity_rq(req))
279 			control |= NVME_RW_PRINFO_PRACT;
280 	}
281 
282 	cmnd->rw.control = cpu_to_le16(control);
283 	cmnd->rw.dsmgmt = cpu_to_le32(dsmgmt);
284 }
285 
286 int nvme_setup_cmd(struct nvme_ns *ns, struct request *req,
287 		struct nvme_command *cmd)
288 {
289 	int ret = 0;
290 
291 	if (req->cmd_type == REQ_TYPE_DRV_PRIV)
292 		memcpy(cmd, req->cmd, sizeof(*cmd));
293 	else if (req->cmd_flags & REQ_FLUSH)
294 		nvme_setup_flush(ns, cmd);
295 	else if (req->cmd_flags & REQ_DISCARD)
296 		ret = nvme_setup_discard(ns, req, cmd);
297 	else
298 		nvme_setup_rw(ns, req, cmd);
299 
300 	return ret;
301 }
302 EXPORT_SYMBOL_GPL(nvme_setup_cmd);
303 
304 /*
305  * Returns 0 on success.  If the result is negative, it's a Linux error code;
306  * if the result is positive, it's an NVM Express status code
307  */
308 int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
309 		struct nvme_completion *cqe, void *buffer, unsigned bufflen,
310 		unsigned timeout)
311 {
312 	struct request *req;
313 	int ret;
314 
315 	req = nvme_alloc_request(q, cmd, 0);
316 	if (IS_ERR(req))
317 		return PTR_ERR(req);
318 
319 	req->timeout = timeout ? timeout : ADMIN_TIMEOUT;
320 	req->special = cqe;
321 
322 	if (buffer && bufflen) {
323 		ret = blk_rq_map_kern(q, req, buffer, bufflen, GFP_KERNEL);
324 		if (ret)
325 			goto out;
326 	}
327 
328 	blk_execute_rq(req->q, NULL, req, 0);
329 	ret = req->errors;
330  out:
331 	blk_mq_free_request(req);
332 	return ret;
333 }
334 
335 int nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
336 		void *buffer, unsigned bufflen)
337 {
338 	return __nvme_submit_sync_cmd(q, cmd, NULL, buffer, bufflen, 0);
339 }
340 EXPORT_SYMBOL_GPL(nvme_submit_sync_cmd);
341 
342 int __nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
343 		void __user *ubuffer, unsigned bufflen,
344 		void __user *meta_buffer, unsigned meta_len, u32 meta_seed,
345 		u32 *result, unsigned timeout)
346 {
347 	bool write = cmd->common.opcode & 1;
348 	struct nvme_completion cqe;
349 	struct nvme_ns *ns = q->queuedata;
350 	struct gendisk *disk = ns ? ns->disk : NULL;
351 	struct request *req;
352 	struct bio *bio = NULL;
353 	void *meta = NULL;
354 	int ret;
355 
356 	req = nvme_alloc_request(q, cmd, 0);
357 	if (IS_ERR(req))
358 		return PTR_ERR(req);
359 
360 	req->timeout = timeout ? timeout : ADMIN_TIMEOUT;
361 	req->special = &cqe;
362 
363 	if (ubuffer && bufflen) {
364 		ret = blk_rq_map_user(q, req, NULL, ubuffer, bufflen,
365 				GFP_KERNEL);
366 		if (ret)
367 			goto out;
368 		bio = req->bio;
369 
370 		if (!disk)
371 			goto submit;
372 		bio->bi_bdev = bdget_disk(disk, 0);
373 		if (!bio->bi_bdev) {
374 			ret = -ENODEV;
375 			goto out_unmap;
376 		}
377 
378 		if (meta_buffer && meta_len) {
379 			struct bio_integrity_payload *bip;
380 
381 			meta = kmalloc(meta_len, GFP_KERNEL);
382 			if (!meta) {
383 				ret = -ENOMEM;
384 				goto out_unmap;
385 			}
386 
387 			if (write) {
388 				if (copy_from_user(meta, meta_buffer,
389 						meta_len)) {
390 					ret = -EFAULT;
391 					goto out_free_meta;
392 				}
393 			}
394 
395 			bip = bio_integrity_alloc(bio, GFP_KERNEL, 1);
396 			if (IS_ERR(bip)) {
397 				ret = PTR_ERR(bip);
398 				goto out_free_meta;
399 			}
400 
401 			bip->bip_iter.bi_size = meta_len;
402 			bip->bip_iter.bi_sector = meta_seed;
403 
404 			ret = bio_integrity_add_page(bio, virt_to_page(meta),
405 					meta_len, offset_in_page(meta));
406 			if (ret != meta_len) {
407 				ret = -ENOMEM;
408 				goto out_free_meta;
409 			}
410 		}
411 	}
412  submit:
413 	blk_execute_rq(req->q, disk, req, 0);
414 	ret = req->errors;
415 	if (result)
416 		*result = le32_to_cpu(cqe.result);
417 	if (meta && !ret && !write) {
418 		if (copy_to_user(meta_buffer, meta, meta_len))
419 			ret = -EFAULT;
420 	}
421  out_free_meta:
422 	kfree(meta);
423  out_unmap:
424 	if (bio) {
425 		if (disk && bio->bi_bdev)
426 			bdput(bio->bi_bdev);
427 		blk_rq_unmap_user(bio);
428 	}
429  out:
430 	blk_mq_free_request(req);
431 	return ret;
432 }
433 
434 int nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
435 		void __user *ubuffer, unsigned bufflen, u32 *result,
436 		unsigned timeout)
437 {
438 	return __nvme_submit_user_cmd(q, cmd, ubuffer, bufflen, NULL, 0, 0,
439 			result, timeout);
440 }
441 
442 int nvme_identify_ctrl(struct nvme_ctrl *dev, struct nvme_id_ctrl **id)
443 {
444 	struct nvme_command c = { };
445 	int error;
446 
447 	/* gcc-4.4.4 (at least) has issues with initializers and anon unions */
448 	c.identify.opcode = nvme_admin_identify;
449 	c.identify.cns = cpu_to_le32(1);
450 
451 	*id = kmalloc(sizeof(struct nvme_id_ctrl), GFP_KERNEL);
452 	if (!*id)
453 		return -ENOMEM;
454 
455 	error = nvme_submit_sync_cmd(dev->admin_q, &c, *id,
456 			sizeof(struct nvme_id_ctrl));
457 	if (error)
458 		kfree(*id);
459 	return error;
460 }
461 
462 static int nvme_identify_ns_list(struct nvme_ctrl *dev, unsigned nsid, __le32 *ns_list)
463 {
464 	struct nvme_command c = { };
465 
466 	c.identify.opcode = nvme_admin_identify;
467 	c.identify.cns = cpu_to_le32(2);
468 	c.identify.nsid = cpu_to_le32(nsid);
469 	return nvme_submit_sync_cmd(dev->admin_q, &c, ns_list, 0x1000);
470 }
471 
472 int nvme_identify_ns(struct nvme_ctrl *dev, unsigned nsid,
473 		struct nvme_id_ns **id)
474 {
475 	struct nvme_command c = { };
476 	int error;
477 
478 	/* gcc-4.4.4 (at least) has issues with initializers and anon unions */
479 	c.identify.opcode = nvme_admin_identify,
480 	c.identify.nsid = cpu_to_le32(nsid),
481 
482 	*id = kmalloc(sizeof(struct nvme_id_ns), GFP_KERNEL);
483 	if (!*id)
484 		return -ENOMEM;
485 
486 	error = nvme_submit_sync_cmd(dev->admin_q, &c, *id,
487 			sizeof(struct nvme_id_ns));
488 	if (error)
489 		kfree(*id);
490 	return error;
491 }
492 
493 int nvme_get_features(struct nvme_ctrl *dev, unsigned fid, unsigned nsid,
494 					dma_addr_t dma_addr, u32 *result)
495 {
496 	struct nvme_command c;
497 	struct nvme_completion cqe;
498 	int ret;
499 
500 	memset(&c, 0, sizeof(c));
501 	c.features.opcode = nvme_admin_get_features;
502 	c.features.nsid = cpu_to_le32(nsid);
503 	c.features.prp1 = cpu_to_le64(dma_addr);
504 	c.features.fid = cpu_to_le32(fid);
505 
506 	ret = __nvme_submit_sync_cmd(dev->admin_q, &c, &cqe, NULL, 0, 0);
507 	if (ret >= 0)
508 		*result = le32_to_cpu(cqe.result);
509 	return ret;
510 }
511 
512 int nvme_set_features(struct nvme_ctrl *dev, unsigned fid, unsigned dword11,
513 					dma_addr_t dma_addr, u32 *result)
514 {
515 	struct nvme_command c;
516 	struct nvme_completion cqe;
517 	int ret;
518 
519 	memset(&c, 0, sizeof(c));
520 	c.features.opcode = nvme_admin_set_features;
521 	c.features.prp1 = cpu_to_le64(dma_addr);
522 	c.features.fid = cpu_to_le32(fid);
523 	c.features.dword11 = cpu_to_le32(dword11);
524 
525 	ret = __nvme_submit_sync_cmd(dev->admin_q, &c, &cqe, NULL, 0, 0);
526 	if (ret >= 0)
527 		*result = le32_to_cpu(cqe.result);
528 	return ret;
529 }
530 
531 int nvme_get_log_page(struct nvme_ctrl *dev, struct nvme_smart_log **log)
532 {
533 	struct nvme_command c = { };
534 	int error;
535 
536 	c.common.opcode = nvme_admin_get_log_page,
537 	c.common.nsid = cpu_to_le32(0xFFFFFFFF),
538 	c.common.cdw10[0] = cpu_to_le32(
539 			(((sizeof(struct nvme_smart_log) / 4) - 1) << 16) |
540 			 NVME_LOG_SMART),
541 
542 	*log = kmalloc(sizeof(struct nvme_smart_log), GFP_KERNEL);
543 	if (!*log)
544 		return -ENOMEM;
545 
546 	error = nvme_submit_sync_cmd(dev->admin_q, &c, *log,
547 			sizeof(struct nvme_smart_log));
548 	if (error)
549 		kfree(*log);
550 	return error;
551 }
552 
553 int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count)
554 {
555 	u32 q_count = (*count - 1) | ((*count - 1) << 16);
556 	u32 result;
557 	int status, nr_io_queues;
558 
559 	status = nvme_set_features(ctrl, NVME_FEAT_NUM_QUEUES, q_count, 0,
560 			&result);
561 	if (status)
562 		return status;
563 
564 	nr_io_queues = min(result & 0xffff, result >> 16) + 1;
565 	*count = min(*count, nr_io_queues);
566 	return 0;
567 }
568 EXPORT_SYMBOL_GPL(nvme_set_queue_count);
569 
570 static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio)
571 {
572 	struct nvme_user_io io;
573 	struct nvme_command c;
574 	unsigned length, meta_len;
575 	void __user *metadata;
576 
577 	if (copy_from_user(&io, uio, sizeof(io)))
578 		return -EFAULT;
579 	if (io.flags)
580 		return -EINVAL;
581 
582 	switch (io.opcode) {
583 	case nvme_cmd_write:
584 	case nvme_cmd_read:
585 	case nvme_cmd_compare:
586 		break;
587 	default:
588 		return -EINVAL;
589 	}
590 
591 	length = (io.nblocks + 1) << ns->lba_shift;
592 	meta_len = (io.nblocks + 1) * ns->ms;
593 	metadata = (void __user *)(uintptr_t)io.metadata;
594 
595 	if (ns->ext) {
596 		length += meta_len;
597 		meta_len = 0;
598 	} else if (meta_len) {
599 		if ((io.metadata & 3) || !io.metadata)
600 			return -EINVAL;
601 	}
602 
603 	memset(&c, 0, sizeof(c));
604 	c.rw.opcode = io.opcode;
605 	c.rw.flags = io.flags;
606 	c.rw.nsid = cpu_to_le32(ns->ns_id);
607 	c.rw.slba = cpu_to_le64(io.slba);
608 	c.rw.length = cpu_to_le16(io.nblocks);
609 	c.rw.control = cpu_to_le16(io.control);
610 	c.rw.dsmgmt = cpu_to_le32(io.dsmgmt);
611 	c.rw.reftag = cpu_to_le32(io.reftag);
612 	c.rw.apptag = cpu_to_le16(io.apptag);
613 	c.rw.appmask = cpu_to_le16(io.appmask);
614 
615 	return __nvme_submit_user_cmd(ns->queue, &c,
616 			(void __user *)(uintptr_t)io.addr, length,
617 			metadata, meta_len, io.slba, NULL, 0);
618 }
619 
620 static int nvme_user_cmd(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
621 			struct nvme_passthru_cmd __user *ucmd)
622 {
623 	struct nvme_passthru_cmd cmd;
624 	struct nvme_command c;
625 	unsigned timeout = 0;
626 	int status;
627 
628 	if (!capable(CAP_SYS_ADMIN))
629 		return -EACCES;
630 	if (copy_from_user(&cmd, ucmd, sizeof(cmd)))
631 		return -EFAULT;
632 	if (cmd.flags)
633 		return -EINVAL;
634 
635 	memset(&c, 0, sizeof(c));
636 	c.common.opcode = cmd.opcode;
637 	c.common.flags = cmd.flags;
638 	c.common.nsid = cpu_to_le32(cmd.nsid);
639 	c.common.cdw2[0] = cpu_to_le32(cmd.cdw2);
640 	c.common.cdw2[1] = cpu_to_le32(cmd.cdw3);
641 	c.common.cdw10[0] = cpu_to_le32(cmd.cdw10);
642 	c.common.cdw10[1] = cpu_to_le32(cmd.cdw11);
643 	c.common.cdw10[2] = cpu_to_le32(cmd.cdw12);
644 	c.common.cdw10[3] = cpu_to_le32(cmd.cdw13);
645 	c.common.cdw10[4] = cpu_to_le32(cmd.cdw14);
646 	c.common.cdw10[5] = cpu_to_le32(cmd.cdw15);
647 
648 	if (cmd.timeout_ms)
649 		timeout = msecs_to_jiffies(cmd.timeout_ms);
650 
651 	status = nvme_submit_user_cmd(ns ? ns->queue : ctrl->admin_q, &c,
652 			(void __user *)(uintptr_t)cmd.addr, cmd.data_len,
653 			&cmd.result, timeout);
654 	if (status >= 0) {
655 		if (put_user(cmd.result, &ucmd->result))
656 			return -EFAULT;
657 	}
658 
659 	return status;
660 }
661 
662 static int nvme_ioctl(struct block_device *bdev, fmode_t mode,
663 		unsigned int cmd, unsigned long arg)
664 {
665 	struct nvme_ns *ns = bdev->bd_disk->private_data;
666 
667 	switch (cmd) {
668 	case NVME_IOCTL_ID:
669 		force_successful_syscall_return();
670 		return ns->ns_id;
671 	case NVME_IOCTL_ADMIN_CMD:
672 		return nvme_user_cmd(ns->ctrl, NULL, (void __user *)arg);
673 	case NVME_IOCTL_IO_CMD:
674 		return nvme_user_cmd(ns->ctrl, ns, (void __user *)arg);
675 	case NVME_IOCTL_SUBMIT_IO:
676 		return nvme_submit_io(ns, (void __user *)arg);
677 #ifdef CONFIG_BLK_DEV_NVME_SCSI
678 	case SG_GET_VERSION_NUM:
679 		return nvme_sg_get_version_num((void __user *)arg);
680 	case SG_IO:
681 		return nvme_sg_io(ns, (void __user *)arg);
682 #endif
683 	default:
684 		return -ENOTTY;
685 	}
686 }
687 
688 #ifdef CONFIG_COMPAT
689 static int nvme_compat_ioctl(struct block_device *bdev, fmode_t mode,
690 			unsigned int cmd, unsigned long arg)
691 {
692 	switch (cmd) {
693 	case SG_IO:
694 		return -ENOIOCTLCMD;
695 	}
696 	return nvme_ioctl(bdev, mode, cmd, arg);
697 }
698 #else
699 #define nvme_compat_ioctl	NULL
700 #endif
701 
702 static int nvme_open(struct block_device *bdev, fmode_t mode)
703 {
704 	return nvme_get_ns_from_disk(bdev->bd_disk) ? 0 : -ENXIO;
705 }
706 
707 static void nvme_release(struct gendisk *disk, fmode_t mode)
708 {
709 	struct nvme_ns *ns = disk->private_data;
710 
711 	module_put(ns->ctrl->ops->module);
712 	nvme_put_ns(ns);
713 }
714 
715 static int nvme_getgeo(struct block_device *bdev, struct hd_geometry *geo)
716 {
717 	/* some standard values */
718 	geo->heads = 1 << 6;
719 	geo->sectors = 1 << 5;
720 	geo->cylinders = get_capacity(bdev->bd_disk) >> 11;
721 	return 0;
722 }
723 
724 #ifdef CONFIG_BLK_DEV_INTEGRITY
725 static void nvme_init_integrity(struct nvme_ns *ns)
726 {
727 	struct blk_integrity integrity;
728 
729 	switch (ns->pi_type) {
730 	case NVME_NS_DPS_PI_TYPE3:
731 		integrity.profile = &t10_pi_type3_crc;
732 		integrity.tag_size = sizeof(u16) + sizeof(u32);
733 		integrity.flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
734 		break;
735 	case NVME_NS_DPS_PI_TYPE1:
736 	case NVME_NS_DPS_PI_TYPE2:
737 		integrity.profile = &t10_pi_type1_crc;
738 		integrity.tag_size = sizeof(u16);
739 		integrity.flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
740 		break;
741 	default:
742 		integrity.profile = NULL;
743 		break;
744 	}
745 	integrity.tuple_size = ns->ms;
746 	blk_integrity_register(ns->disk, &integrity);
747 	blk_queue_max_integrity_segments(ns->queue, 1);
748 }
749 #else
750 static void nvme_init_integrity(struct nvme_ns *ns)
751 {
752 }
753 #endif /* CONFIG_BLK_DEV_INTEGRITY */
754 
755 static void nvme_config_discard(struct nvme_ns *ns)
756 {
757 	struct nvme_ctrl *ctrl = ns->ctrl;
758 	u32 logical_block_size = queue_logical_block_size(ns->queue);
759 
760 	if (ctrl->quirks & NVME_QUIRK_DISCARD_ZEROES)
761 		ns->queue->limits.discard_zeroes_data = 1;
762 	else
763 		ns->queue->limits.discard_zeroes_data = 0;
764 
765 	ns->queue->limits.discard_alignment = logical_block_size;
766 	ns->queue->limits.discard_granularity = logical_block_size;
767 	blk_queue_max_discard_sectors(ns->queue, 0xffffffff);
768 	queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, ns->queue);
769 }
770 
771 static int nvme_revalidate_disk(struct gendisk *disk)
772 {
773 	struct nvme_ns *ns = disk->private_data;
774 	struct nvme_id_ns *id;
775 	u8 lbaf, pi_type;
776 	u16 old_ms;
777 	unsigned short bs;
778 
779 	if (test_bit(NVME_NS_DEAD, &ns->flags)) {
780 		set_capacity(disk, 0);
781 		return -ENODEV;
782 	}
783 	if (nvme_identify_ns(ns->ctrl, ns->ns_id, &id)) {
784 		dev_warn(disk_to_dev(ns->disk), "%s: Identify failure\n",
785 				__func__);
786 		return -ENODEV;
787 	}
788 	if (id->ncap == 0) {
789 		kfree(id);
790 		return -ENODEV;
791 	}
792 
793 	if (nvme_nvm_ns_supported(ns, id) && ns->type != NVME_NS_LIGHTNVM) {
794 		if (nvme_nvm_register(ns->queue, disk->disk_name)) {
795 			dev_warn(disk_to_dev(ns->disk),
796 				"%s: LightNVM init failure\n", __func__);
797 			kfree(id);
798 			return -ENODEV;
799 		}
800 		ns->type = NVME_NS_LIGHTNVM;
801 	}
802 
803 	if (ns->ctrl->vs >= NVME_VS(1, 1))
804 		memcpy(ns->eui, id->eui64, sizeof(ns->eui));
805 	if (ns->ctrl->vs >= NVME_VS(1, 2))
806 		memcpy(ns->uuid, id->nguid, sizeof(ns->uuid));
807 
808 	old_ms = ns->ms;
809 	lbaf = id->flbas & NVME_NS_FLBAS_LBA_MASK;
810 	ns->lba_shift = id->lbaf[lbaf].ds;
811 	ns->ms = le16_to_cpu(id->lbaf[lbaf].ms);
812 	ns->ext = ns->ms && (id->flbas & NVME_NS_FLBAS_META_EXT);
813 
814 	/*
815 	 * If identify namespace failed, use default 512 byte block size so
816 	 * block layer can use before failing read/write for 0 capacity.
817 	 */
818 	if (ns->lba_shift == 0)
819 		ns->lba_shift = 9;
820 	bs = 1 << ns->lba_shift;
821 	/* XXX: PI implementation requires metadata equal t10 pi tuple size */
822 	pi_type = ns->ms == sizeof(struct t10_pi_tuple) ?
823 					id->dps & NVME_NS_DPS_PI_MASK : 0;
824 
825 	blk_mq_freeze_queue(disk->queue);
826 	if (blk_get_integrity(disk) && (ns->pi_type != pi_type ||
827 				ns->ms != old_ms ||
828 				bs != queue_logical_block_size(disk->queue) ||
829 				(ns->ms && ns->ext)))
830 		blk_integrity_unregister(disk);
831 
832 	ns->pi_type = pi_type;
833 	blk_queue_logical_block_size(ns->queue, bs);
834 
835 	if (ns->ms && !blk_get_integrity(disk) && !ns->ext)
836 		nvme_init_integrity(ns);
837 	if (ns->ms && !(ns->ms == 8 && ns->pi_type) && !blk_get_integrity(disk))
838 		set_capacity(disk, 0);
839 	else
840 		set_capacity(disk, le64_to_cpup(&id->nsze) << (ns->lba_shift - 9));
841 
842 	if (ns->ctrl->oncs & NVME_CTRL_ONCS_DSM)
843 		nvme_config_discard(ns);
844 	blk_mq_unfreeze_queue(disk->queue);
845 
846 	kfree(id);
847 	return 0;
848 }
849 
850 static char nvme_pr_type(enum pr_type type)
851 {
852 	switch (type) {
853 	case PR_WRITE_EXCLUSIVE:
854 		return 1;
855 	case PR_EXCLUSIVE_ACCESS:
856 		return 2;
857 	case PR_WRITE_EXCLUSIVE_REG_ONLY:
858 		return 3;
859 	case PR_EXCLUSIVE_ACCESS_REG_ONLY:
860 		return 4;
861 	case PR_WRITE_EXCLUSIVE_ALL_REGS:
862 		return 5;
863 	case PR_EXCLUSIVE_ACCESS_ALL_REGS:
864 		return 6;
865 	default:
866 		return 0;
867 	}
868 };
869 
870 static int nvme_pr_command(struct block_device *bdev, u32 cdw10,
871 				u64 key, u64 sa_key, u8 op)
872 {
873 	struct nvme_ns *ns = bdev->bd_disk->private_data;
874 	struct nvme_command c;
875 	u8 data[16] = { 0, };
876 
877 	put_unaligned_le64(key, &data[0]);
878 	put_unaligned_le64(sa_key, &data[8]);
879 
880 	memset(&c, 0, sizeof(c));
881 	c.common.opcode = op;
882 	c.common.nsid = cpu_to_le32(ns->ns_id);
883 	c.common.cdw10[0] = cpu_to_le32(cdw10);
884 
885 	return nvme_submit_sync_cmd(ns->queue, &c, data, 16);
886 }
887 
888 static int nvme_pr_register(struct block_device *bdev, u64 old,
889 		u64 new, unsigned flags)
890 {
891 	u32 cdw10;
892 
893 	if (flags & ~PR_FL_IGNORE_KEY)
894 		return -EOPNOTSUPP;
895 
896 	cdw10 = old ? 2 : 0;
897 	cdw10 |= (flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0;
898 	cdw10 |= (1 << 30) | (1 << 31); /* PTPL=1 */
899 	return nvme_pr_command(bdev, cdw10, old, new, nvme_cmd_resv_register);
900 }
901 
902 static int nvme_pr_reserve(struct block_device *bdev, u64 key,
903 		enum pr_type type, unsigned flags)
904 {
905 	u32 cdw10;
906 
907 	if (flags & ~PR_FL_IGNORE_KEY)
908 		return -EOPNOTSUPP;
909 
910 	cdw10 = nvme_pr_type(type) << 8;
911 	cdw10 |= ((flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0);
912 	return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_acquire);
913 }
914 
915 static int nvme_pr_preempt(struct block_device *bdev, u64 old, u64 new,
916 		enum pr_type type, bool abort)
917 {
918 	u32 cdw10 = nvme_pr_type(type) << 8 | abort ? 2 : 1;
919 	return nvme_pr_command(bdev, cdw10, old, new, nvme_cmd_resv_acquire);
920 }
921 
922 static int nvme_pr_clear(struct block_device *bdev, u64 key)
923 {
924 	u32 cdw10 = 1 | (key ? 1 << 3 : 0);
925 	return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_register);
926 }
927 
928 static int nvme_pr_release(struct block_device *bdev, u64 key, enum pr_type type)
929 {
930 	u32 cdw10 = nvme_pr_type(type) << 8 | key ? 1 << 3 : 0;
931 	return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_release);
932 }
933 
934 static const struct pr_ops nvme_pr_ops = {
935 	.pr_register	= nvme_pr_register,
936 	.pr_reserve	= nvme_pr_reserve,
937 	.pr_release	= nvme_pr_release,
938 	.pr_preempt	= nvme_pr_preempt,
939 	.pr_clear	= nvme_pr_clear,
940 };
941 
942 static const struct block_device_operations nvme_fops = {
943 	.owner		= THIS_MODULE,
944 	.ioctl		= nvme_ioctl,
945 	.compat_ioctl	= nvme_compat_ioctl,
946 	.open		= nvme_open,
947 	.release	= nvme_release,
948 	.getgeo		= nvme_getgeo,
949 	.revalidate_disk= nvme_revalidate_disk,
950 	.pr_ops		= &nvme_pr_ops,
951 };
952 
953 static int nvme_wait_ready(struct nvme_ctrl *ctrl, u64 cap, bool enabled)
954 {
955 	unsigned long timeout =
956 		((NVME_CAP_TIMEOUT(cap) + 1) * HZ / 2) + jiffies;
957 	u32 csts, bit = enabled ? NVME_CSTS_RDY : 0;
958 	int ret;
959 
960 	while ((ret = ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &csts)) == 0) {
961 		if ((csts & NVME_CSTS_RDY) == bit)
962 			break;
963 
964 		msleep(100);
965 		if (fatal_signal_pending(current))
966 			return -EINTR;
967 		if (time_after(jiffies, timeout)) {
968 			dev_err(ctrl->device,
969 				"Device not ready; aborting %s\n", enabled ?
970 						"initialisation" : "reset");
971 			return -ENODEV;
972 		}
973 	}
974 
975 	return ret;
976 }
977 
978 /*
979  * If the device has been passed off to us in an enabled state, just clear
980  * the enabled bit.  The spec says we should set the 'shutdown notification
981  * bits', but doing so may cause the device to complete commands to the
982  * admin queue ... and we don't know what memory that might be pointing at!
983  */
984 int nvme_disable_ctrl(struct nvme_ctrl *ctrl, u64 cap)
985 {
986 	int ret;
987 
988 	ctrl->ctrl_config &= ~NVME_CC_SHN_MASK;
989 	ctrl->ctrl_config &= ~NVME_CC_ENABLE;
990 
991 	ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
992 	if (ret)
993 		return ret;
994 	return nvme_wait_ready(ctrl, cap, false);
995 }
996 EXPORT_SYMBOL_GPL(nvme_disable_ctrl);
997 
998 int nvme_enable_ctrl(struct nvme_ctrl *ctrl, u64 cap)
999 {
1000 	/*
1001 	 * Default to a 4K page size, with the intention to update this
1002 	 * path in the future to accomodate architectures with differing
1003 	 * kernel and IO page sizes.
1004 	 */
1005 	unsigned dev_page_min = NVME_CAP_MPSMIN(cap) + 12, page_shift = 12;
1006 	int ret;
1007 
1008 	if (page_shift < dev_page_min) {
1009 		dev_err(ctrl->device,
1010 			"Minimum device page size %u too large for host (%u)\n",
1011 			1 << dev_page_min, 1 << page_shift);
1012 		return -ENODEV;
1013 	}
1014 
1015 	ctrl->page_size = 1 << page_shift;
1016 
1017 	ctrl->ctrl_config = NVME_CC_CSS_NVM;
1018 	ctrl->ctrl_config |= (page_shift - 12) << NVME_CC_MPS_SHIFT;
1019 	ctrl->ctrl_config |= NVME_CC_ARB_RR | NVME_CC_SHN_NONE;
1020 	ctrl->ctrl_config |= NVME_CC_IOSQES | NVME_CC_IOCQES;
1021 	ctrl->ctrl_config |= NVME_CC_ENABLE;
1022 
1023 	ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
1024 	if (ret)
1025 		return ret;
1026 	return nvme_wait_ready(ctrl, cap, true);
1027 }
1028 EXPORT_SYMBOL_GPL(nvme_enable_ctrl);
1029 
1030 int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl)
1031 {
1032 	unsigned long timeout = SHUTDOWN_TIMEOUT + jiffies;
1033 	u32 csts;
1034 	int ret;
1035 
1036 	ctrl->ctrl_config &= ~NVME_CC_SHN_MASK;
1037 	ctrl->ctrl_config |= NVME_CC_SHN_NORMAL;
1038 
1039 	ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
1040 	if (ret)
1041 		return ret;
1042 
1043 	while ((ret = ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &csts)) == 0) {
1044 		if ((csts & NVME_CSTS_SHST_MASK) == NVME_CSTS_SHST_CMPLT)
1045 			break;
1046 
1047 		msleep(100);
1048 		if (fatal_signal_pending(current))
1049 			return -EINTR;
1050 		if (time_after(jiffies, timeout)) {
1051 			dev_err(ctrl->device,
1052 				"Device shutdown incomplete; abort shutdown\n");
1053 			return -ENODEV;
1054 		}
1055 	}
1056 
1057 	return ret;
1058 }
1059 EXPORT_SYMBOL_GPL(nvme_shutdown_ctrl);
1060 
1061 static void nvme_set_queue_limits(struct nvme_ctrl *ctrl,
1062 		struct request_queue *q)
1063 {
1064 	bool vwc = false;
1065 
1066 	if (ctrl->max_hw_sectors) {
1067 		u32 max_segments =
1068 			(ctrl->max_hw_sectors / (ctrl->page_size >> 9)) + 1;
1069 
1070 		blk_queue_max_hw_sectors(q, ctrl->max_hw_sectors);
1071 		blk_queue_max_segments(q, min_t(u32, max_segments, USHRT_MAX));
1072 	}
1073 	if (ctrl->stripe_size)
1074 		blk_queue_chunk_sectors(q, ctrl->stripe_size >> 9);
1075 	blk_queue_virt_boundary(q, ctrl->page_size - 1);
1076 	if (ctrl->vwc & NVME_CTRL_VWC_PRESENT)
1077 		vwc = true;
1078 	blk_queue_write_cache(q, vwc, vwc);
1079 }
1080 
1081 /*
1082  * Initialize the cached copies of the Identify data and various controller
1083  * register in our nvme_ctrl structure.  This should be called as soon as
1084  * the admin queue is fully up and running.
1085  */
1086 int nvme_init_identify(struct nvme_ctrl *ctrl)
1087 {
1088 	struct nvme_id_ctrl *id;
1089 	u64 cap;
1090 	int ret, page_shift;
1091 
1092 	ret = ctrl->ops->reg_read32(ctrl, NVME_REG_VS, &ctrl->vs);
1093 	if (ret) {
1094 		dev_err(ctrl->device, "Reading VS failed (%d)\n", ret);
1095 		return ret;
1096 	}
1097 
1098 	ret = ctrl->ops->reg_read64(ctrl, NVME_REG_CAP, &cap);
1099 	if (ret) {
1100 		dev_err(ctrl->device, "Reading CAP failed (%d)\n", ret);
1101 		return ret;
1102 	}
1103 	page_shift = NVME_CAP_MPSMIN(cap) + 12;
1104 
1105 	if (ctrl->vs >= NVME_VS(1, 1))
1106 		ctrl->subsystem = NVME_CAP_NSSRC(cap);
1107 
1108 	ret = nvme_identify_ctrl(ctrl, &id);
1109 	if (ret) {
1110 		dev_err(ctrl->device, "Identify Controller failed (%d)\n", ret);
1111 		return -EIO;
1112 	}
1113 
1114 	ctrl->vid = le16_to_cpu(id->vid);
1115 	ctrl->oncs = le16_to_cpup(&id->oncs);
1116 	atomic_set(&ctrl->abort_limit, id->acl + 1);
1117 	ctrl->vwc = id->vwc;
1118 	ctrl->cntlid = le16_to_cpup(&id->cntlid);
1119 	memcpy(ctrl->serial, id->sn, sizeof(id->sn));
1120 	memcpy(ctrl->model, id->mn, sizeof(id->mn));
1121 	memcpy(ctrl->firmware_rev, id->fr, sizeof(id->fr));
1122 	if (id->mdts)
1123 		ctrl->max_hw_sectors = 1 << (id->mdts + page_shift - 9);
1124 	else
1125 		ctrl->max_hw_sectors = UINT_MAX;
1126 
1127 	if ((ctrl->quirks & NVME_QUIRK_STRIPE_SIZE) && id->vs[3]) {
1128 		unsigned int max_hw_sectors;
1129 
1130 		ctrl->stripe_size = 1 << (id->vs[3] + page_shift);
1131 		max_hw_sectors = ctrl->stripe_size >> (page_shift - 9);
1132 		if (ctrl->max_hw_sectors) {
1133 			ctrl->max_hw_sectors = min(max_hw_sectors,
1134 							ctrl->max_hw_sectors);
1135 		} else {
1136 			ctrl->max_hw_sectors = max_hw_sectors;
1137 		}
1138 	}
1139 
1140 	nvme_set_queue_limits(ctrl, ctrl->admin_q);
1141 
1142 	kfree(id);
1143 	return 0;
1144 }
1145 EXPORT_SYMBOL_GPL(nvme_init_identify);
1146 
1147 static int nvme_dev_open(struct inode *inode, struct file *file)
1148 {
1149 	struct nvme_ctrl *ctrl;
1150 	int instance = iminor(inode);
1151 	int ret = -ENODEV;
1152 
1153 	spin_lock(&dev_list_lock);
1154 	list_for_each_entry(ctrl, &nvme_ctrl_list, node) {
1155 		if (ctrl->instance != instance)
1156 			continue;
1157 
1158 		if (!ctrl->admin_q) {
1159 			ret = -EWOULDBLOCK;
1160 			break;
1161 		}
1162 		if (!kref_get_unless_zero(&ctrl->kref))
1163 			break;
1164 		file->private_data = ctrl;
1165 		ret = 0;
1166 		break;
1167 	}
1168 	spin_unlock(&dev_list_lock);
1169 
1170 	return ret;
1171 }
1172 
1173 static int nvme_dev_release(struct inode *inode, struct file *file)
1174 {
1175 	nvme_put_ctrl(file->private_data);
1176 	return 0;
1177 }
1178 
1179 static int nvme_dev_user_cmd(struct nvme_ctrl *ctrl, void __user *argp)
1180 {
1181 	struct nvme_ns *ns;
1182 	int ret;
1183 
1184 	mutex_lock(&ctrl->namespaces_mutex);
1185 	if (list_empty(&ctrl->namespaces)) {
1186 		ret = -ENOTTY;
1187 		goto out_unlock;
1188 	}
1189 
1190 	ns = list_first_entry(&ctrl->namespaces, struct nvme_ns, list);
1191 	if (ns != list_last_entry(&ctrl->namespaces, struct nvme_ns, list)) {
1192 		dev_warn(ctrl->device,
1193 			"NVME_IOCTL_IO_CMD not supported when multiple namespaces present!\n");
1194 		ret = -EINVAL;
1195 		goto out_unlock;
1196 	}
1197 
1198 	dev_warn(ctrl->device,
1199 		"using deprecated NVME_IOCTL_IO_CMD ioctl on the char device!\n");
1200 	kref_get(&ns->kref);
1201 	mutex_unlock(&ctrl->namespaces_mutex);
1202 
1203 	ret = nvme_user_cmd(ctrl, ns, argp);
1204 	nvme_put_ns(ns);
1205 	return ret;
1206 
1207 out_unlock:
1208 	mutex_unlock(&ctrl->namespaces_mutex);
1209 	return ret;
1210 }
1211 
1212 static long nvme_dev_ioctl(struct file *file, unsigned int cmd,
1213 		unsigned long arg)
1214 {
1215 	struct nvme_ctrl *ctrl = file->private_data;
1216 	void __user *argp = (void __user *)arg;
1217 
1218 	switch (cmd) {
1219 	case NVME_IOCTL_ADMIN_CMD:
1220 		return nvme_user_cmd(ctrl, NULL, argp);
1221 	case NVME_IOCTL_IO_CMD:
1222 		return nvme_dev_user_cmd(ctrl, argp);
1223 	case NVME_IOCTL_RESET:
1224 		dev_warn(ctrl->device, "resetting controller\n");
1225 		return ctrl->ops->reset_ctrl(ctrl);
1226 	case NVME_IOCTL_SUBSYS_RESET:
1227 		return nvme_reset_subsystem(ctrl);
1228 	case NVME_IOCTL_RESCAN:
1229 		nvme_queue_scan(ctrl);
1230 		return 0;
1231 	default:
1232 		return -ENOTTY;
1233 	}
1234 }
1235 
1236 static const struct file_operations nvme_dev_fops = {
1237 	.owner		= THIS_MODULE,
1238 	.open		= nvme_dev_open,
1239 	.release	= nvme_dev_release,
1240 	.unlocked_ioctl	= nvme_dev_ioctl,
1241 	.compat_ioctl	= nvme_dev_ioctl,
1242 };
1243 
1244 static ssize_t nvme_sysfs_reset(struct device *dev,
1245 				struct device_attribute *attr, const char *buf,
1246 				size_t count)
1247 {
1248 	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
1249 	int ret;
1250 
1251 	ret = ctrl->ops->reset_ctrl(ctrl);
1252 	if (ret < 0)
1253 		return ret;
1254 	return count;
1255 }
1256 static DEVICE_ATTR(reset_controller, S_IWUSR, NULL, nvme_sysfs_reset);
1257 
1258 static ssize_t nvme_sysfs_rescan(struct device *dev,
1259 				struct device_attribute *attr, const char *buf,
1260 				size_t count)
1261 {
1262 	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
1263 
1264 	nvme_queue_scan(ctrl);
1265 	return count;
1266 }
1267 static DEVICE_ATTR(rescan_controller, S_IWUSR, NULL, nvme_sysfs_rescan);
1268 
1269 static ssize_t wwid_show(struct device *dev, struct device_attribute *attr,
1270 								char *buf)
1271 {
1272 	struct nvme_ns *ns = dev_to_disk(dev)->private_data;
1273 	struct nvme_ctrl *ctrl = ns->ctrl;
1274 	int serial_len = sizeof(ctrl->serial);
1275 	int model_len = sizeof(ctrl->model);
1276 
1277 	if (memchr_inv(ns->uuid, 0, sizeof(ns->uuid)))
1278 		return sprintf(buf, "eui.%16phN\n", ns->uuid);
1279 
1280 	if (memchr_inv(ns->eui, 0, sizeof(ns->eui)))
1281 		return sprintf(buf, "eui.%8phN\n", ns->eui);
1282 
1283 	while (ctrl->serial[serial_len - 1] == ' ')
1284 		serial_len--;
1285 	while (ctrl->model[model_len - 1] == ' ')
1286 		model_len--;
1287 
1288 	return sprintf(buf, "nvme.%04x-%*phN-%*phN-%08x\n", ctrl->vid,
1289 		serial_len, ctrl->serial, model_len, ctrl->model, ns->ns_id);
1290 }
1291 static DEVICE_ATTR(wwid, S_IRUGO, wwid_show, NULL);
1292 
1293 static ssize_t uuid_show(struct device *dev, struct device_attribute *attr,
1294 								char *buf)
1295 {
1296 	struct nvme_ns *ns = dev_to_disk(dev)->private_data;
1297 	return sprintf(buf, "%pU\n", ns->uuid);
1298 }
1299 static DEVICE_ATTR(uuid, S_IRUGO, uuid_show, NULL);
1300 
1301 static ssize_t eui_show(struct device *dev, struct device_attribute *attr,
1302 								char *buf)
1303 {
1304 	struct nvme_ns *ns = dev_to_disk(dev)->private_data;
1305 	return sprintf(buf, "%8phd\n", ns->eui);
1306 }
1307 static DEVICE_ATTR(eui, S_IRUGO, eui_show, NULL);
1308 
1309 static ssize_t nsid_show(struct device *dev, struct device_attribute *attr,
1310 								char *buf)
1311 {
1312 	struct nvme_ns *ns = dev_to_disk(dev)->private_data;
1313 	return sprintf(buf, "%d\n", ns->ns_id);
1314 }
1315 static DEVICE_ATTR(nsid, S_IRUGO, nsid_show, NULL);
1316 
1317 static struct attribute *nvme_ns_attrs[] = {
1318 	&dev_attr_wwid.attr,
1319 	&dev_attr_uuid.attr,
1320 	&dev_attr_eui.attr,
1321 	&dev_attr_nsid.attr,
1322 	NULL,
1323 };
1324 
1325 static umode_t nvme_attrs_are_visible(struct kobject *kobj,
1326 		struct attribute *a, int n)
1327 {
1328 	struct device *dev = container_of(kobj, struct device, kobj);
1329 	struct nvme_ns *ns = dev_to_disk(dev)->private_data;
1330 
1331 	if (a == &dev_attr_uuid.attr) {
1332 		if (!memchr_inv(ns->uuid, 0, sizeof(ns->uuid)))
1333 			return 0;
1334 	}
1335 	if (a == &dev_attr_eui.attr) {
1336 		if (!memchr_inv(ns->eui, 0, sizeof(ns->eui)))
1337 			return 0;
1338 	}
1339 	return a->mode;
1340 }
1341 
1342 static const struct attribute_group nvme_ns_attr_group = {
1343 	.attrs		= nvme_ns_attrs,
1344 	.is_visible	= nvme_attrs_are_visible,
1345 };
1346 
1347 #define nvme_show_str_function(field)						\
1348 static ssize_t  field##_show(struct device *dev,				\
1349 			    struct device_attribute *attr, char *buf)		\
1350 {										\
1351         struct nvme_ctrl *ctrl = dev_get_drvdata(dev);				\
1352         return sprintf(buf, "%.*s\n", (int)sizeof(ctrl->field), ctrl->field);	\
1353 }										\
1354 static DEVICE_ATTR(field, S_IRUGO, field##_show, NULL);
1355 
1356 #define nvme_show_int_function(field)						\
1357 static ssize_t  field##_show(struct device *dev,				\
1358 			    struct device_attribute *attr, char *buf)		\
1359 {										\
1360         struct nvme_ctrl *ctrl = dev_get_drvdata(dev);				\
1361         return sprintf(buf, "%d\n", ctrl->field);	\
1362 }										\
1363 static DEVICE_ATTR(field, S_IRUGO, field##_show, NULL);
1364 
1365 nvme_show_str_function(model);
1366 nvme_show_str_function(serial);
1367 nvme_show_str_function(firmware_rev);
1368 nvme_show_int_function(cntlid);
1369 
1370 static struct attribute *nvme_dev_attrs[] = {
1371 	&dev_attr_reset_controller.attr,
1372 	&dev_attr_rescan_controller.attr,
1373 	&dev_attr_model.attr,
1374 	&dev_attr_serial.attr,
1375 	&dev_attr_firmware_rev.attr,
1376 	&dev_attr_cntlid.attr,
1377 	NULL
1378 };
1379 
1380 static struct attribute_group nvme_dev_attrs_group = {
1381 	.attrs = nvme_dev_attrs,
1382 };
1383 
1384 static const struct attribute_group *nvme_dev_attr_groups[] = {
1385 	&nvme_dev_attrs_group,
1386 	NULL,
1387 };
1388 
1389 static int ns_cmp(void *priv, struct list_head *a, struct list_head *b)
1390 {
1391 	struct nvme_ns *nsa = container_of(a, struct nvme_ns, list);
1392 	struct nvme_ns *nsb = container_of(b, struct nvme_ns, list);
1393 
1394 	return nsa->ns_id - nsb->ns_id;
1395 }
1396 
1397 static struct nvme_ns *nvme_find_ns(struct nvme_ctrl *ctrl, unsigned nsid)
1398 {
1399 	struct nvme_ns *ns;
1400 
1401 	lockdep_assert_held(&ctrl->namespaces_mutex);
1402 
1403 	list_for_each_entry(ns, &ctrl->namespaces, list) {
1404 		if (ns->ns_id == nsid)
1405 			return ns;
1406 		if (ns->ns_id > nsid)
1407 			break;
1408 	}
1409 	return NULL;
1410 }
1411 
1412 static void nvme_alloc_ns(struct nvme_ctrl *ctrl, unsigned nsid)
1413 {
1414 	struct nvme_ns *ns;
1415 	struct gendisk *disk;
1416 	int node = dev_to_node(ctrl->dev);
1417 
1418 	lockdep_assert_held(&ctrl->namespaces_mutex);
1419 
1420 	ns = kzalloc_node(sizeof(*ns), GFP_KERNEL, node);
1421 	if (!ns)
1422 		return;
1423 
1424 	ns->instance = ida_simple_get(&ctrl->ns_ida, 1, 0, GFP_KERNEL);
1425 	if (ns->instance < 0)
1426 		goto out_free_ns;
1427 
1428 	ns->queue = blk_mq_init_queue(ctrl->tagset);
1429 	if (IS_ERR(ns->queue))
1430 		goto out_release_instance;
1431 	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, ns->queue);
1432 	ns->queue->queuedata = ns;
1433 	ns->ctrl = ctrl;
1434 
1435 	disk = alloc_disk_node(0, node);
1436 	if (!disk)
1437 		goto out_free_queue;
1438 
1439 	kref_init(&ns->kref);
1440 	ns->ns_id = nsid;
1441 	ns->disk = disk;
1442 	ns->lba_shift = 9; /* set to a default value for 512 until disk is validated */
1443 
1444 
1445 	blk_queue_logical_block_size(ns->queue, 1 << ns->lba_shift);
1446 	nvme_set_queue_limits(ctrl, ns->queue);
1447 
1448 	disk->major = nvme_major;
1449 	disk->first_minor = 0;
1450 	disk->fops = &nvme_fops;
1451 	disk->private_data = ns;
1452 	disk->queue = ns->queue;
1453 	disk->driverfs_dev = ctrl->device;
1454 	disk->flags = GENHD_FL_EXT_DEVT;
1455 	sprintf(disk->disk_name, "nvme%dn%d", ctrl->instance, ns->instance);
1456 
1457 	if (nvme_revalidate_disk(ns->disk))
1458 		goto out_free_disk;
1459 
1460 	list_add_tail_rcu(&ns->list, &ctrl->namespaces);
1461 	kref_get(&ctrl->kref);
1462 	if (ns->type == NVME_NS_LIGHTNVM)
1463 		return;
1464 
1465 	add_disk(ns->disk);
1466 	if (sysfs_create_group(&disk_to_dev(ns->disk)->kobj,
1467 					&nvme_ns_attr_group))
1468 		pr_warn("%s: failed to create sysfs group for identification\n",
1469 			ns->disk->disk_name);
1470 	return;
1471  out_free_disk:
1472 	kfree(disk);
1473  out_free_queue:
1474 	blk_cleanup_queue(ns->queue);
1475  out_release_instance:
1476 	ida_simple_remove(&ctrl->ns_ida, ns->instance);
1477  out_free_ns:
1478 	kfree(ns);
1479 }
1480 
1481 static void nvme_ns_remove(struct nvme_ns *ns)
1482 {
1483 	lockdep_assert_held(&ns->ctrl->namespaces_mutex);
1484 
1485 	if (test_and_set_bit(NVME_NS_REMOVING, &ns->flags))
1486 		return;
1487 
1488 	if (ns->disk->flags & GENHD_FL_UP) {
1489 		if (blk_get_integrity(ns->disk))
1490 			blk_integrity_unregister(ns->disk);
1491 		sysfs_remove_group(&disk_to_dev(ns->disk)->kobj,
1492 					&nvme_ns_attr_group);
1493 		del_gendisk(ns->disk);
1494 		blk_mq_abort_requeue_list(ns->queue);
1495 		blk_cleanup_queue(ns->queue);
1496 	}
1497 	list_del_init(&ns->list);
1498 	synchronize_rcu();
1499 	nvme_put_ns(ns);
1500 }
1501 
1502 static void nvme_validate_ns(struct nvme_ctrl *ctrl, unsigned nsid)
1503 {
1504 	struct nvme_ns *ns;
1505 
1506 	ns = nvme_find_ns(ctrl, nsid);
1507 	if (ns) {
1508 		if (revalidate_disk(ns->disk))
1509 			nvme_ns_remove(ns);
1510 	} else
1511 		nvme_alloc_ns(ctrl, nsid);
1512 }
1513 
1514 static int nvme_scan_ns_list(struct nvme_ctrl *ctrl, unsigned nn)
1515 {
1516 	struct nvme_ns *ns;
1517 	__le32 *ns_list;
1518 	unsigned i, j, nsid, prev = 0, num_lists = DIV_ROUND_UP(nn, 1024);
1519 	int ret = 0;
1520 
1521 	ns_list = kzalloc(0x1000, GFP_KERNEL);
1522 	if (!ns_list)
1523 		return -ENOMEM;
1524 
1525 	for (i = 0; i < num_lists; i++) {
1526 		ret = nvme_identify_ns_list(ctrl, prev, ns_list);
1527 		if (ret)
1528 			goto out;
1529 
1530 		for (j = 0; j < min(nn, 1024U); j++) {
1531 			nsid = le32_to_cpu(ns_list[j]);
1532 			if (!nsid)
1533 				goto out;
1534 
1535 			nvme_validate_ns(ctrl, nsid);
1536 
1537 			while (++prev < nsid) {
1538 				ns = nvme_find_ns(ctrl, prev);
1539 				if (ns)
1540 					nvme_ns_remove(ns);
1541 			}
1542 		}
1543 		nn -= j;
1544 	}
1545  out:
1546 	kfree(ns_list);
1547 	return ret;
1548 }
1549 
1550 static void nvme_scan_ns_sequential(struct nvme_ctrl *ctrl, unsigned nn)
1551 {
1552 	struct nvme_ns *ns, *next;
1553 	unsigned i;
1554 
1555 	lockdep_assert_held(&ctrl->namespaces_mutex);
1556 
1557 	for (i = 1; i <= nn; i++)
1558 		nvme_validate_ns(ctrl, i);
1559 
1560 	list_for_each_entry_safe(ns, next, &ctrl->namespaces, list) {
1561 		if (ns->ns_id > nn)
1562 			nvme_ns_remove(ns);
1563 	}
1564 }
1565 
1566 static void nvme_scan_work(struct work_struct *work)
1567 {
1568 	struct nvme_ctrl *ctrl =
1569 		container_of(work, struct nvme_ctrl, scan_work);
1570 	struct nvme_id_ctrl *id;
1571 	unsigned nn;
1572 
1573 	if (ctrl->state != NVME_CTRL_LIVE)
1574 		return;
1575 
1576 	if (nvme_identify_ctrl(ctrl, &id))
1577 		return;
1578 
1579 	mutex_lock(&ctrl->namespaces_mutex);
1580 	nn = le32_to_cpu(id->nn);
1581 	if (ctrl->vs >= NVME_VS(1, 1) &&
1582 	    !(ctrl->quirks & NVME_QUIRK_IDENTIFY_CNS)) {
1583 		if (!nvme_scan_ns_list(ctrl, nn))
1584 			goto done;
1585 	}
1586 	nvme_scan_ns_sequential(ctrl, nn);
1587  done:
1588 	list_sort(NULL, &ctrl->namespaces, ns_cmp);
1589 	mutex_unlock(&ctrl->namespaces_mutex);
1590 	kfree(id);
1591 
1592 	if (ctrl->ops->post_scan)
1593 		ctrl->ops->post_scan(ctrl);
1594 }
1595 
1596 void nvme_queue_scan(struct nvme_ctrl *ctrl)
1597 {
1598 	/*
1599 	 * Do not queue new scan work when a controller is reset during
1600 	 * removal.
1601 	 */
1602 	if (ctrl->state == NVME_CTRL_LIVE)
1603 		schedule_work(&ctrl->scan_work);
1604 }
1605 EXPORT_SYMBOL_GPL(nvme_queue_scan);
1606 
1607 void nvme_remove_namespaces(struct nvme_ctrl *ctrl)
1608 {
1609 	struct nvme_ns *ns, *next;
1610 
1611 	/*
1612 	 * The dead states indicates the controller was not gracefully
1613 	 * disconnected. In that case, we won't be able to flush any data while
1614 	 * removing the namespaces' disks; fail all the queues now to avoid
1615 	 * potentially having to clean up the failed sync later.
1616 	 */
1617 	if (ctrl->state == NVME_CTRL_DEAD)
1618 		nvme_kill_queues(ctrl);
1619 
1620 	mutex_lock(&ctrl->namespaces_mutex);
1621 	list_for_each_entry_safe(ns, next, &ctrl->namespaces, list)
1622 		nvme_ns_remove(ns);
1623 	mutex_unlock(&ctrl->namespaces_mutex);
1624 }
1625 EXPORT_SYMBOL_GPL(nvme_remove_namespaces);
1626 
1627 static void nvme_async_event_work(struct work_struct *work)
1628 {
1629 	struct nvme_ctrl *ctrl =
1630 		container_of(work, struct nvme_ctrl, async_event_work);
1631 
1632 	spin_lock_irq(&ctrl->lock);
1633 	while (ctrl->event_limit > 0) {
1634 		int aer_idx = --ctrl->event_limit;
1635 
1636 		spin_unlock_irq(&ctrl->lock);
1637 		ctrl->ops->submit_async_event(ctrl, aer_idx);
1638 		spin_lock_irq(&ctrl->lock);
1639 	}
1640 	spin_unlock_irq(&ctrl->lock);
1641 }
1642 
1643 void nvme_complete_async_event(struct nvme_ctrl *ctrl,
1644 		struct nvme_completion *cqe)
1645 {
1646 	u16 status = le16_to_cpu(cqe->status) >> 1;
1647 	u32 result = le32_to_cpu(cqe->result);
1648 
1649 	if (status == NVME_SC_SUCCESS || status == NVME_SC_ABORT_REQ) {
1650 		++ctrl->event_limit;
1651 		schedule_work(&ctrl->async_event_work);
1652 	}
1653 
1654 	if (status != NVME_SC_SUCCESS)
1655 		return;
1656 
1657 	switch (result & 0xff07) {
1658 	case NVME_AER_NOTICE_NS_CHANGED:
1659 		dev_info(ctrl->device, "rescanning\n");
1660 		nvme_queue_scan(ctrl);
1661 		break;
1662 	default:
1663 		dev_warn(ctrl->device, "async event result %08x\n", result);
1664 	}
1665 }
1666 EXPORT_SYMBOL_GPL(nvme_complete_async_event);
1667 
1668 void nvme_queue_async_events(struct nvme_ctrl *ctrl)
1669 {
1670 	ctrl->event_limit = NVME_NR_AERS;
1671 	schedule_work(&ctrl->async_event_work);
1672 }
1673 EXPORT_SYMBOL_GPL(nvme_queue_async_events);
1674 
1675 static DEFINE_IDA(nvme_instance_ida);
1676 
1677 static int nvme_set_instance(struct nvme_ctrl *ctrl)
1678 {
1679 	int instance, error;
1680 
1681 	do {
1682 		if (!ida_pre_get(&nvme_instance_ida, GFP_KERNEL))
1683 			return -ENODEV;
1684 
1685 		spin_lock(&dev_list_lock);
1686 		error = ida_get_new(&nvme_instance_ida, &instance);
1687 		spin_unlock(&dev_list_lock);
1688 	} while (error == -EAGAIN);
1689 
1690 	if (error)
1691 		return -ENODEV;
1692 
1693 	ctrl->instance = instance;
1694 	return 0;
1695 }
1696 
1697 static void nvme_release_instance(struct nvme_ctrl *ctrl)
1698 {
1699 	spin_lock(&dev_list_lock);
1700 	ida_remove(&nvme_instance_ida, ctrl->instance);
1701 	spin_unlock(&dev_list_lock);
1702 }
1703 
1704 void nvme_uninit_ctrl(struct nvme_ctrl *ctrl)
1705 {
1706 	flush_work(&ctrl->async_event_work);
1707 	flush_work(&ctrl->scan_work);
1708 	nvme_remove_namespaces(ctrl);
1709 
1710 	device_destroy(nvme_class, MKDEV(nvme_char_major, ctrl->instance));
1711 
1712 	spin_lock(&dev_list_lock);
1713 	list_del(&ctrl->node);
1714 	spin_unlock(&dev_list_lock);
1715 }
1716 EXPORT_SYMBOL_GPL(nvme_uninit_ctrl);
1717 
1718 static void nvme_free_ctrl(struct kref *kref)
1719 {
1720 	struct nvme_ctrl *ctrl = container_of(kref, struct nvme_ctrl, kref);
1721 
1722 	put_device(ctrl->device);
1723 	nvme_release_instance(ctrl);
1724 	ida_destroy(&ctrl->ns_ida);
1725 
1726 	ctrl->ops->free_ctrl(ctrl);
1727 }
1728 
1729 void nvme_put_ctrl(struct nvme_ctrl *ctrl)
1730 {
1731 	kref_put(&ctrl->kref, nvme_free_ctrl);
1732 }
1733 EXPORT_SYMBOL_GPL(nvme_put_ctrl);
1734 
1735 /*
1736  * Initialize a NVMe controller structures.  This needs to be called during
1737  * earliest initialization so that we have the initialized structured around
1738  * during probing.
1739  */
1740 int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
1741 		const struct nvme_ctrl_ops *ops, unsigned long quirks)
1742 {
1743 	int ret;
1744 
1745 	ctrl->state = NVME_CTRL_NEW;
1746 	spin_lock_init(&ctrl->lock);
1747 	INIT_LIST_HEAD(&ctrl->namespaces);
1748 	mutex_init(&ctrl->namespaces_mutex);
1749 	kref_init(&ctrl->kref);
1750 	ctrl->dev = dev;
1751 	ctrl->ops = ops;
1752 	ctrl->quirks = quirks;
1753 	INIT_WORK(&ctrl->scan_work, nvme_scan_work);
1754 	INIT_WORK(&ctrl->async_event_work, nvme_async_event_work);
1755 
1756 	ret = nvme_set_instance(ctrl);
1757 	if (ret)
1758 		goto out;
1759 
1760 	ctrl->device = device_create_with_groups(nvme_class, ctrl->dev,
1761 				MKDEV(nvme_char_major, ctrl->instance),
1762 				ctrl, nvme_dev_attr_groups,
1763 				"nvme%d", ctrl->instance);
1764 	if (IS_ERR(ctrl->device)) {
1765 		ret = PTR_ERR(ctrl->device);
1766 		goto out_release_instance;
1767 	}
1768 	get_device(ctrl->device);
1769 	ida_init(&ctrl->ns_ida);
1770 
1771 	spin_lock(&dev_list_lock);
1772 	list_add_tail(&ctrl->node, &nvme_ctrl_list);
1773 	spin_unlock(&dev_list_lock);
1774 
1775 	return 0;
1776 out_release_instance:
1777 	nvme_release_instance(ctrl);
1778 out:
1779 	return ret;
1780 }
1781 EXPORT_SYMBOL_GPL(nvme_init_ctrl);
1782 
1783 /**
1784  * nvme_kill_queues(): Ends all namespace queues
1785  * @ctrl: the dead controller that needs to end
1786  *
1787  * Call this function when the driver determines it is unable to get the
1788  * controller in a state capable of servicing IO.
1789  */
1790 void nvme_kill_queues(struct nvme_ctrl *ctrl)
1791 {
1792 	struct nvme_ns *ns;
1793 
1794 	rcu_read_lock();
1795 	list_for_each_entry_rcu(ns, &ctrl->namespaces, list) {
1796 		if (!kref_get_unless_zero(&ns->kref))
1797 			continue;
1798 
1799 		/*
1800 		 * Revalidating a dead namespace sets capacity to 0. This will
1801 		 * end buffered writers dirtying pages that can't be synced.
1802 		 */
1803 		if (!test_and_set_bit(NVME_NS_DEAD, &ns->flags))
1804 			revalidate_disk(ns->disk);
1805 
1806 		blk_set_queue_dying(ns->queue);
1807 		blk_mq_abort_requeue_list(ns->queue);
1808 		blk_mq_start_stopped_hw_queues(ns->queue, true);
1809 
1810 		nvme_put_ns(ns);
1811 	}
1812 	rcu_read_unlock();
1813 }
1814 EXPORT_SYMBOL_GPL(nvme_kill_queues);
1815 
1816 void nvme_stop_queues(struct nvme_ctrl *ctrl)
1817 {
1818 	struct nvme_ns *ns;
1819 
1820 	rcu_read_lock();
1821 	list_for_each_entry_rcu(ns, &ctrl->namespaces, list) {
1822 		spin_lock_irq(ns->queue->queue_lock);
1823 		queue_flag_set(QUEUE_FLAG_STOPPED, ns->queue);
1824 		spin_unlock_irq(ns->queue->queue_lock);
1825 
1826 		blk_mq_cancel_requeue_work(ns->queue);
1827 		blk_mq_stop_hw_queues(ns->queue);
1828 	}
1829 	rcu_read_unlock();
1830 }
1831 EXPORT_SYMBOL_GPL(nvme_stop_queues);
1832 
1833 void nvme_start_queues(struct nvme_ctrl *ctrl)
1834 {
1835 	struct nvme_ns *ns;
1836 
1837 	rcu_read_lock();
1838 	list_for_each_entry_rcu(ns, &ctrl->namespaces, list) {
1839 		queue_flag_clear_unlocked(QUEUE_FLAG_STOPPED, ns->queue);
1840 		blk_mq_start_stopped_hw_queues(ns->queue, true);
1841 		blk_mq_kick_requeue_list(ns->queue);
1842 	}
1843 	rcu_read_unlock();
1844 }
1845 EXPORT_SYMBOL_GPL(nvme_start_queues);
1846 
1847 int __init nvme_core_init(void)
1848 {
1849 	int result;
1850 
1851 	result = register_blkdev(nvme_major, "nvme");
1852 	if (result < 0)
1853 		return result;
1854 	else if (result > 0)
1855 		nvme_major = result;
1856 
1857 	result = __register_chrdev(nvme_char_major, 0, NVME_MINORS, "nvme",
1858 							&nvme_dev_fops);
1859 	if (result < 0)
1860 		goto unregister_blkdev;
1861 	else if (result > 0)
1862 		nvme_char_major = result;
1863 
1864 	nvme_class = class_create(THIS_MODULE, "nvme");
1865 	if (IS_ERR(nvme_class)) {
1866 		result = PTR_ERR(nvme_class);
1867 		goto unregister_chrdev;
1868 	}
1869 
1870 	return 0;
1871 
1872  unregister_chrdev:
1873 	__unregister_chrdev(nvme_char_major, 0, NVME_MINORS, "nvme");
1874  unregister_blkdev:
1875 	unregister_blkdev(nvme_major, "nvme");
1876 	return result;
1877 }
1878 
1879 void nvme_core_exit(void)
1880 {
1881 	class_destroy(nvme_class);
1882 	__unregister_chrdev(nvme_char_major, 0, NVME_MINORS, "nvme");
1883 	unregister_blkdev(nvme_major, "nvme");
1884 }
1885 
1886 MODULE_LICENSE("GPL");
1887 MODULE_VERSION("1.0");
1888 module_init(nvme_core_init);
1889 module_exit(nvme_core_exit);
1890