xref: /linux/drivers/nvme/host/core.c (revision 3b812ecce736432e6b55e77028ea387eb1517d24)
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 static int nvme_major;
37 module_param(nvme_major, int, 0);
38 
39 static int nvme_char_major;
40 module_param(nvme_char_major, int, 0);
41 
42 static LIST_HEAD(nvme_ctrl_list);
43 DEFINE_SPINLOCK(dev_list_lock);
44 
45 static struct class *nvme_class;
46 
47 static void nvme_free_ns(struct kref *kref)
48 {
49 	struct nvme_ns *ns = container_of(kref, struct nvme_ns, kref);
50 
51 	if (ns->type == NVME_NS_LIGHTNVM)
52 		nvme_nvm_unregister(ns->queue, ns->disk->disk_name);
53 
54 	spin_lock(&dev_list_lock);
55 	ns->disk->private_data = NULL;
56 	spin_unlock(&dev_list_lock);
57 
58 	put_disk(ns->disk);
59 	ida_simple_remove(&ns->ctrl->ns_ida, ns->instance);
60 	nvme_put_ctrl(ns->ctrl);
61 	kfree(ns);
62 }
63 
64 static void nvme_put_ns(struct nvme_ns *ns)
65 {
66 	kref_put(&ns->kref, nvme_free_ns);
67 }
68 
69 static struct nvme_ns *nvme_get_ns_from_disk(struct gendisk *disk)
70 {
71 	struct nvme_ns *ns;
72 
73 	spin_lock(&dev_list_lock);
74 	ns = disk->private_data;
75 	if (ns && !kref_get_unless_zero(&ns->kref))
76 		ns = NULL;
77 	spin_unlock(&dev_list_lock);
78 
79 	return ns;
80 }
81 
82 void nvme_requeue_req(struct request *req)
83 {
84 	unsigned long flags;
85 
86 	blk_mq_requeue_request(req);
87 	spin_lock_irqsave(req->q->queue_lock, flags);
88 	if (!blk_queue_stopped(req->q))
89 		blk_mq_kick_requeue_list(req->q);
90 	spin_unlock_irqrestore(req->q->queue_lock, flags);
91 }
92 
93 struct request *nvme_alloc_request(struct request_queue *q,
94 		struct nvme_command *cmd, unsigned int flags)
95 {
96 	bool write = cmd->common.opcode & 1;
97 	struct request *req;
98 
99 	req = blk_mq_alloc_request(q, write, flags);
100 	if (IS_ERR(req))
101 		return req;
102 
103 	req->cmd_type = REQ_TYPE_DRV_PRIV;
104 	req->cmd_flags |= REQ_FAILFAST_DRIVER;
105 	req->__data_len = 0;
106 	req->__sector = (sector_t) -1;
107 	req->bio = req->biotail = NULL;
108 
109 	req->cmd = (unsigned char *)cmd;
110 	req->cmd_len = sizeof(struct nvme_command);
111 	req->special = (void *)0;
112 
113 	return req;
114 }
115 
116 /*
117  * Returns 0 on success.  If the result is negative, it's a Linux error code;
118  * if the result is positive, it's an NVM Express status code
119  */
120 int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
121 		void *buffer, unsigned bufflen, u32 *result, unsigned timeout)
122 {
123 	struct request *req;
124 	int ret;
125 
126 	req = nvme_alloc_request(q, cmd, 0);
127 	if (IS_ERR(req))
128 		return PTR_ERR(req);
129 
130 	req->timeout = timeout ? timeout : ADMIN_TIMEOUT;
131 
132 	if (buffer && bufflen) {
133 		ret = blk_rq_map_kern(q, req, buffer, bufflen, GFP_KERNEL);
134 		if (ret)
135 			goto out;
136 	}
137 
138 	blk_execute_rq(req->q, NULL, req, 0);
139 	if (result)
140 		*result = (u32)(uintptr_t)req->special;
141 	ret = req->errors;
142  out:
143 	blk_mq_free_request(req);
144 	return ret;
145 }
146 
147 int nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
148 		void *buffer, unsigned bufflen)
149 {
150 	return __nvme_submit_sync_cmd(q, cmd, buffer, bufflen, NULL, 0);
151 }
152 
153 int __nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
154 		void __user *ubuffer, unsigned bufflen,
155 		void __user *meta_buffer, unsigned meta_len, u32 meta_seed,
156 		u32 *result, unsigned timeout)
157 {
158 	bool write = cmd->common.opcode & 1;
159 	struct nvme_ns *ns = q->queuedata;
160 	struct gendisk *disk = ns ? ns->disk : NULL;
161 	struct request *req;
162 	struct bio *bio = NULL;
163 	void *meta = NULL;
164 	int ret;
165 
166 	req = nvme_alloc_request(q, cmd, 0);
167 	if (IS_ERR(req))
168 		return PTR_ERR(req);
169 
170 	req->timeout = timeout ? timeout : ADMIN_TIMEOUT;
171 
172 	if (ubuffer && bufflen) {
173 		ret = blk_rq_map_user(q, req, NULL, ubuffer, bufflen,
174 				GFP_KERNEL);
175 		if (ret)
176 			goto out;
177 		bio = req->bio;
178 
179 		if (!disk)
180 			goto submit;
181 		bio->bi_bdev = bdget_disk(disk, 0);
182 		if (!bio->bi_bdev) {
183 			ret = -ENODEV;
184 			goto out_unmap;
185 		}
186 
187 		if (meta_buffer && meta_len) {
188 			struct bio_integrity_payload *bip;
189 
190 			meta = kmalloc(meta_len, GFP_KERNEL);
191 			if (!meta) {
192 				ret = -ENOMEM;
193 				goto out_unmap;
194 			}
195 
196 			if (write) {
197 				if (copy_from_user(meta, meta_buffer,
198 						meta_len)) {
199 					ret = -EFAULT;
200 					goto out_free_meta;
201 				}
202 			}
203 
204 			bip = bio_integrity_alloc(bio, GFP_KERNEL, 1);
205 			if (IS_ERR(bip)) {
206 				ret = PTR_ERR(bip);
207 				goto out_free_meta;
208 			}
209 
210 			bip->bip_iter.bi_size = meta_len;
211 			bip->bip_iter.bi_sector = meta_seed;
212 
213 			ret = bio_integrity_add_page(bio, virt_to_page(meta),
214 					meta_len, offset_in_page(meta));
215 			if (ret != meta_len) {
216 				ret = -ENOMEM;
217 				goto out_free_meta;
218 			}
219 		}
220 	}
221  submit:
222 	blk_execute_rq(req->q, disk, req, 0);
223 	ret = req->errors;
224 	if (result)
225 		*result = (u32)(uintptr_t)req->special;
226 	if (meta && !ret && !write) {
227 		if (copy_to_user(meta_buffer, meta, meta_len))
228 			ret = -EFAULT;
229 	}
230  out_free_meta:
231 	kfree(meta);
232  out_unmap:
233 	if (bio) {
234 		if (disk && bio->bi_bdev)
235 			bdput(bio->bi_bdev);
236 		blk_rq_unmap_user(bio);
237 	}
238  out:
239 	blk_mq_free_request(req);
240 	return ret;
241 }
242 
243 int nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
244 		void __user *ubuffer, unsigned bufflen, u32 *result,
245 		unsigned timeout)
246 {
247 	return __nvme_submit_user_cmd(q, cmd, ubuffer, bufflen, NULL, 0, 0,
248 			result, timeout);
249 }
250 
251 int nvme_identify_ctrl(struct nvme_ctrl *dev, struct nvme_id_ctrl **id)
252 {
253 	struct nvme_command c = { };
254 	int error;
255 
256 	/* gcc-4.4.4 (at least) has issues with initializers and anon unions */
257 	c.identify.opcode = nvme_admin_identify;
258 	c.identify.cns = cpu_to_le32(1);
259 
260 	*id = kmalloc(sizeof(struct nvme_id_ctrl), GFP_KERNEL);
261 	if (!*id)
262 		return -ENOMEM;
263 
264 	error = nvme_submit_sync_cmd(dev->admin_q, &c, *id,
265 			sizeof(struct nvme_id_ctrl));
266 	if (error)
267 		kfree(*id);
268 	return error;
269 }
270 
271 static int nvme_identify_ns_list(struct nvme_ctrl *dev, unsigned nsid, __le32 *ns_list)
272 {
273 	struct nvme_command c = { };
274 
275 	c.identify.opcode = nvme_admin_identify;
276 	c.identify.cns = cpu_to_le32(2);
277 	c.identify.nsid = cpu_to_le32(nsid);
278 	return nvme_submit_sync_cmd(dev->admin_q, &c, ns_list, 0x1000);
279 }
280 
281 int nvme_identify_ns(struct nvme_ctrl *dev, unsigned nsid,
282 		struct nvme_id_ns **id)
283 {
284 	struct nvme_command c = { };
285 	int error;
286 
287 	/* gcc-4.4.4 (at least) has issues with initializers and anon unions */
288 	c.identify.opcode = nvme_admin_identify,
289 	c.identify.nsid = cpu_to_le32(nsid),
290 
291 	*id = kmalloc(sizeof(struct nvme_id_ns), GFP_KERNEL);
292 	if (!*id)
293 		return -ENOMEM;
294 
295 	error = nvme_submit_sync_cmd(dev->admin_q, &c, *id,
296 			sizeof(struct nvme_id_ns));
297 	if (error)
298 		kfree(*id);
299 	return error;
300 }
301 
302 int nvme_get_features(struct nvme_ctrl *dev, unsigned fid, unsigned nsid,
303 					dma_addr_t dma_addr, u32 *result)
304 {
305 	struct nvme_command c;
306 
307 	memset(&c, 0, sizeof(c));
308 	c.features.opcode = nvme_admin_get_features;
309 	c.features.nsid = cpu_to_le32(nsid);
310 	c.features.prp1 = cpu_to_le64(dma_addr);
311 	c.features.fid = cpu_to_le32(fid);
312 
313 	return __nvme_submit_sync_cmd(dev->admin_q, &c, NULL, 0, result, 0);
314 }
315 
316 int nvme_set_features(struct nvme_ctrl *dev, unsigned fid, unsigned dword11,
317 					dma_addr_t dma_addr, u32 *result)
318 {
319 	struct nvme_command c;
320 
321 	memset(&c, 0, sizeof(c));
322 	c.features.opcode = nvme_admin_set_features;
323 	c.features.prp1 = cpu_to_le64(dma_addr);
324 	c.features.fid = cpu_to_le32(fid);
325 	c.features.dword11 = cpu_to_le32(dword11);
326 
327 	return __nvme_submit_sync_cmd(dev->admin_q, &c, NULL, 0, result, 0);
328 }
329 
330 int nvme_get_log_page(struct nvme_ctrl *dev, struct nvme_smart_log **log)
331 {
332 	struct nvme_command c = { };
333 	int error;
334 
335 	c.common.opcode = nvme_admin_get_log_page,
336 	c.common.nsid = cpu_to_le32(0xFFFFFFFF),
337 	c.common.cdw10[0] = cpu_to_le32(
338 			(((sizeof(struct nvme_smart_log) / 4) - 1) << 16) |
339 			 NVME_LOG_SMART),
340 
341 	*log = kmalloc(sizeof(struct nvme_smart_log), GFP_KERNEL);
342 	if (!*log)
343 		return -ENOMEM;
344 
345 	error = nvme_submit_sync_cmd(dev->admin_q, &c, *log,
346 			sizeof(struct nvme_smart_log));
347 	if (error)
348 		kfree(*log);
349 	return error;
350 }
351 
352 int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count)
353 {
354 	u32 q_count = (*count - 1) | ((*count - 1) << 16);
355 	u32 result;
356 	int status, nr_io_queues;
357 
358 	status = nvme_set_features(ctrl, NVME_FEAT_NUM_QUEUES, q_count, 0,
359 			&result);
360 	if (status)
361 		return status;
362 
363 	nr_io_queues = min(result & 0xffff, result >> 16) + 1;
364 	*count = min(*count, nr_io_queues);
365 	return 0;
366 }
367 
368 static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio)
369 {
370 	struct nvme_user_io io;
371 	struct nvme_command c;
372 	unsigned length, meta_len;
373 	void __user *metadata;
374 
375 	if (copy_from_user(&io, uio, sizeof(io)))
376 		return -EFAULT;
377 	if (io.flags)
378 		return -EINVAL;
379 
380 	switch (io.opcode) {
381 	case nvme_cmd_write:
382 	case nvme_cmd_read:
383 	case nvme_cmd_compare:
384 		break;
385 	default:
386 		return -EINVAL;
387 	}
388 
389 	length = (io.nblocks + 1) << ns->lba_shift;
390 	meta_len = (io.nblocks + 1) * ns->ms;
391 	metadata = (void __user *)(uintptr_t)io.metadata;
392 
393 	if (ns->ext) {
394 		length += meta_len;
395 		meta_len = 0;
396 	} else if (meta_len) {
397 		if ((io.metadata & 3) || !io.metadata)
398 			return -EINVAL;
399 	}
400 
401 	memset(&c, 0, sizeof(c));
402 	c.rw.opcode = io.opcode;
403 	c.rw.flags = io.flags;
404 	c.rw.nsid = cpu_to_le32(ns->ns_id);
405 	c.rw.slba = cpu_to_le64(io.slba);
406 	c.rw.length = cpu_to_le16(io.nblocks);
407 	c.rw.control = cpu_to_le16(io.control);
408 	c.rw.dsmgmt = cpu_to_le32(io.dsmgmt);
409 	c.rw.reftag = cpu_to_le32(io.reftag);
410 	c.rw.apptag = cpu_to_le16(io.apptag);
411 	c.rw.appmask = cpu_to_le16(io.appmask);
412 
413 	return __nvme_submit_user_cmd(ns->queue, &c,
414 			(void __user *)(uintptr_t)io.addr, length,
415 			metadata, meta_len, io.slba, NULL, 0);
416 }
417 
418 static int nvme_user_cmd(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
419 			struct nvme_passthru_cmd __user *ucmd)
420 {
421 	struct nvme_passthru_cmd cmd;
422 	struct nvme_command c;
423 	unsigned timeout = 0;
424 	int status;
425 
426 	if (!capable(CAP_SYS_ADMIN))
427 		return -EACCES;
428 	if (copy_from_user(&cmd, ucmd, sizeof(cmd)))
429 		return -EFAULT;
430 	if (cmd.flags)
431 		return -EINVAL;
432 
433 	memset(&c, 0, sizeof(c));
434 	c.common.opcode = cmd.opcode;
435 	c.common.flags = cmd.flags;
436 	c.common.nsid = cpu_to_le32(cmd.nsid);
437 	c.common.cdw2[0] = cpu_to_le32(cmd.cdw2);
438 	c.common.cdw2[1] = cpu_to_le32(cmd.cdw3);
439 	c.common.cdw10[0] = cpu_to_le32(cmd.cdw10);
440 	c.common.cdw10[1] = cpu_to_le32(cmd.cdw11);
441 	c.common.cdw10[2] = cpu_to_le32(cmd.cdw12);
442 	c.common.cdw10[3] = cpu_to_le32(cmd.cdw13);
443 	c.common.cdw10[4] = cpu_to_le32(cmd.cdw14);
444 	c.common.cdw10[5] = cpu_to_le32(cmd.cdw15);
445 
446 	if (cmd.timeout_ms)
447 		timeout = msecs_to_jiffies(cmd.timeout_ms);
448 
449 	status = nvme_submit_user_cmd(ns ? ns->queue : ctrl->admin_q, &c,
450 			(void __user *)(uintptr_t)cmd.addr, cmd.data_len,
451 			&cmd.result, timeout);
452 	if (status >= 0) {
453 		if (put_user(cmd.result, &ucmd->result))
454 			return -EFAULT;
455 	}
456 
457 	return status;
458 }
459 
460 static int nvme_ioctl(struct block_device *bdev, fmode_t mode,
461 		unsigned int cmd, unsigned long arg)
462 {
463 	struct nvme_ns *ns = bdev->bd_disk->private_data;
464 
465 	switch (cmd) {
466 	case NVME_IOCTL_ID:
467 		force_successful_syscall_return();
468 		return ns->ns_id;
469 	case NVME_IOCTL_ADMIN_CMD:
470 		return nvme_user_cmd(ns->ctrl, NULL, (void __user *)arg);
471 	case NVME_IOCTL_IO_CMD:
472 		return nvme_user_cmd(ns->ctrl, ns, (void __user *)arg);
473 	case NVME_IOCTL_SUBMIT_IO:
474 		return nvme_submit_io(ns, (void __user *)arg);
475 #ifdef CONFIG_BLK_DEV_NVME_SCSI
476 	case SG_GET_VERSION_NUM:
477 		return nvme_sg_get_version_num((void __user *)arg);
478 	case SG_IO:
479 		return nvme_sg_io(ns, (void __user *)arg);
480 #endif
481 	default:
482 		return -ENOTTY;
483 	}
484 }
485 
486 #ifdef CONFIG_COMPAT
487 static int nvme_compat_ioctl(struct block_device *bdev, fmode_t mode,
488 			unsigned int cmd, unsigned long arg)
489 {
490 	switch (cmd) {
491 	case SG_IO:
492 		return -ENOIOCTLCMD;
493 	}
494 	return nvme_ioctl(bdev, mode, cmd, arg);
495 }
496 #else
497 #define nvme_compat_ioctl	NULL
498 #endif
499 
500 static int nvme_open(struct block_device *bdev, fmode_t mode)
501 {
502 	return nvme_get_ns_from_disk(bdev->bd_disk) ? 0 : -ENXIO;
503 }
504 
505 static void nvme_release(struct gendisk *disk, fmode_t mode)
506 {
507 	nvme_put_ns(disk->private_data);
508 }
509 
510 static int nvme_getgeo(struct block_device *bdev, struct hd_geometry *geo)
511 {
512 	/* some standard values */
513 	geo->heads = 1 << 6;
514 	geo->sectors = 1 << 5;
515 	geo->cylinders = get_capacity(bdev->bd_disk) >> 11;
516 	return 0;
517 }
518 
519 #ifdef CONFIG_BLK_DEV_INTEGRITY
520 static void nvme_init_integrity(struct nvme_ns *ns)
521 {
522 	struct blk_integrity integrity;
523 
524 	switch (ns->pi_type) {
525 	case NVME_NS_DPS_PI_TYPE3:
526 		integrity.profile = &t10_pi_type3_crc;
527 		break;
528 	case NVME_NS_DPS_PI_TYPE1:
529 	case NVME_NS_DPS_PI_TYPE2:
530 		integrity.profile = &t10_pi_type1_crc;
531 		break;
532 	default:
533 		integrity.profile = NULL;
534 		break;
535 	}
536 	integrity.tuple_size = ns->ms;
537 	blk_integrity_register(ns->disk, &integrity);
538 	blk_queue_max_integrity_segments(ns->queue, 1);
539 }
540 #else
541 static void nvme_init_integrity(struct nvme_ns *ns)
542 {
543 }
544 #endif /* CONFIG_BLK_DEV_INTEGRITY */
545 
546 static void nvme_config_discard(struct nvme_ns *ns)
547 {
548 	u32 logical_block_size = queue_logical_block_size(ns->queue);
549 	ns->queue->limits.discard_zeroes_data = 0;
550 	ns->queue->limits.discard_alignment = logical_block_size;
551 	ns->queue->limits.discard_granularity = logical_block_size;
552 	blk_queue_max_discard_sectors(ns->queue, 0xffffffff);
553 	queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, ns->queue);
554 }
555 
556 static int nvme_revalidate_disk(struct gendisk *disk)
557 {
558 	struct nvme_ns *ns = disk->private_data;
559 	struct nvme_id_ns *id;
560 	u8 lbaf, pi_type;
561 	u16 old_ms;
562 	unsigned short bs;
563 
564 	if (test_bit(NVME_NS_DEAD, &ns->flags)) {
565 		set_capacity(disk, 0);
566 		return -ENODEV;
567 	}
568 	if (nvme_identify_ns(ns->ctrl, ns->ns_id, &id)) {
569 		dev_warn(ns->ctrl->dev, "%s: Identify failure nvme%dn%d\n",
570 				__func__, ns->ctrl->instance, ns->ns_id);
571 		return -ENODEV;
572 	}
573 	if (id->ncap == 0) {
574 		kfree(id);
575 		return -ENODEV;
576 	}
577 
578 	if (nvme_nvm_ns_supported(ns, id) && ns->type != NVME_NS_LIGHTNVM) {
579 		if (nvme_nvm_register(ns->queue, disk->disk_name)) {
580 			dev_warn(ns->ctrl->dev,
581 				"%s: LightNVM init failure\n", __func__);
582 			kfree(id);
583 			return -ENODEV;
584 		}
585 		ns->type = NVME_NS_LIGHTNVM;
586 	}
587 
588 	if (ns->ctrl->vs >= NVME_VS(1, 1))
589 		memcpy(ns->eui, id->eui64, sizeof(ns->eui));
590 	if (ns->ctrl->vs >= NVME_VS(1, 2))
591 		memcpy(ns->uuid, id->nguid, sizeof(ns->uuid));
592 
593 	old_ms = ns->ms;
594 	lbaf = id->flbas & NVME_NS_FLBAS_LBA_MASK;
595 	ns->lba_shift = id->lbaf[lbaf].ds;
596 	ns->ms = le16_to_cpu(id->lbaf[lbaf].ms);
597 	ns->ext = ns->ms && (id->flbas & NVME_NS_FLBAS_META_EXT);
598 
599 	/*
600 	 * If identify namespace failed, use default 512 byte block size so
601 	 * block layer can use before failing read/write for 0 capacity.
602 	 */
603 	if (ns->lba_shift == 0)
604 		ns->lba_shift = 9;
605 	bs = 1 << ns->lba_shift;
606 	/* XXX: PI implementation requires metadata equal t10 pi tuple size */
607 	pi_type = ns->ms == sizeof(struct t10_pi_tuple) ?
608 					id->dps & NVME_NS_DPS_PI_MASK : 0;
609 
610 	blk_mq_freeze_queue(disk->queue);
611 	if (blk_get_integrity(disk) && (ns->pi_type != pi_type ||
612 				ns->ms != old_ms ||
613 				bs != queue_logical_block_size(disk->queue) ||
614 				(ns->ms && ns->ext)))
615 		blk_integrity_unregister(disk);
616 
617 	ns->pi_type = pi_type;
618 	blk_queue_logical_block_size(ns->queue, bs);
619 
620 	if (ns->ms && !blk_get_integrity(disk) && !ns->ext)
621 		nvme_init_integrity(ns);
622 	if (ns->ms && !(ns->ms == 8 && ns->pi_type) && !blk_get_integrity(disk))
623 		set_capacity(disk, 0);
624 	else
625 		set_capacity(disk, le64_to_cpup(&id->nsze) << (ns->lba_shift - 9));
626 
627 	if (ns->ctrl->oncs & NVME_CTRL_ONCS_DSM)
628 		nvme_config_discard(ns);
629 	blk_mq_unfreeze_queue(disk->queue);
630 
631 	kfree(id);
632 	return 0;
633 }
634 
635 static char nvme_pr_type(enum pr_type type)
636 {
637 	switch (type) {
638 	case PR_WRITE_EXCLUSIVE:
639 		return 1;
640 	case PR_EXCLUSIVE_ACCESS:
641 		return 2;
642 	case PR_WRITE_EXCLUSIVE_REG_ONLY:
643 		return 3;
644 	case PR_EXCLUSIVE_ACCESS_REG_ONLY:
645 		return 4;
646 	case PR_WRITE_EXCLUSIVE_ALL_REGS:
647 		return 5;
648 	case PR_EXCLUSIVE_ACCESS_ALL_REGS:
649 		return 6;
650 	default:
651 		return 0;
652 	}
653 };
654 
655 static int nvme_pr_command(struct block_device *bdev, u32 cdw10,
656 				u64 key, u64 sa_key, u8 op)
657 {
658 	struct nvme_ns *ns = bdev->bd_disk->private_data;
659 	struct nvme_command c;
660 	u8 data[16] = { 0, };
661 
662 	put_unaligned_le64(key, &data[0]);
663 	put_unaligned_le64(sa_key, &data[8]);
664 
665 	memset(&c, 0, sizeof(c));
666 	c.common.opcode = op;
667 	c.common.nsid = cpu_to_le32(ns->ns_id);
668 	c.common.cdw10[0] = cpu_to_le32(cdw10);
669 
670 	return nvme_submit_sync_cmd(ns->queue, &c, data, 16);
671 }
672 
673 static int nvme_pr_register(struct block_device *bdev, u64 old,
674 		u64 new, unsigned flags)
675 {
676 	u32 cdw10;
677 
678 	if (flags & ~PR_FL_IGNORE_KEY)
679 		return -EOPNOTSUPP;
680 
681 	cdw10 = old ? 2 : 0;
682 	cdw10 |= (flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0;
683 	cdw10 |= (1 << 30) | (1 << 31); /* PTPL=1 */
684 	return nvme_pr_command(bdev, cdw10, old, new, nvme_cmd_resv_register);
685 }
686 
687 static int nvme_pr_reserve(struct block_device *bdev, u64 key,
688 		enum pr_type type, unsigned flags)
689 {
690 	u32 cdw10;
691 
692 	if (flags & ~PR_FL_IGNORE_KEY)
693 		return -EOPNOTSUPP;
694 
695 	cdw10 = nvme_pr_type(type) << 8;
696 	cdw10 |= ((flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0);
697 	return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_acquire);
698 }
699 
700 static int nvme_pr_preempt(struct block_device *bdev, u64 old, u64 new,
701 		enum pr_type type, bool abort)
702 {
703 	u32 cdw10 = nvme_pr_type(type) << 8 | abort ? 2 : 1;
704 	return nvme_pr_command(bdev, cdw10, old, new, nvme_cmd_resv_acquire);
705 }
706 
707 static int nvme_pr_clear(struct block_device *bdev, u64 key)
708 {
709 	u32 cdw10 = 1 | (key ? 1 << 3 : 0);
710 	return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_register);
711 }
712 
713 static int nvme_pr_release(struct block_device *bdev, u64 key, enum pr_type type)
714 {
715 	u32 cdw10 = nvme_pr_type(type) << 8 | key ? 1 << 3 : 0;
716 	return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_release);
717 }
718 
719 static const struct pr_ops nvme_pr_ops = {
720 	.pr_register	= nvme_pr_register,
721 	.pr_reserve	= nvme_pr_reserve,
722 	.pr_release	= nvme_pr_release,
723 	.pr_preempt	= nvme_pr_preempt,
724 	.pr_clear	= nvme_pr_clear,
725 };
726 
727 static const struct block_device_operations nvme_fops = {
728 	.owner		= THIS_MODULE,
729 	.ioctl		= nvme_ioctl,
730 	.compat_ioctl	= nvme_compat_ioctl,
731 	.open		= nvme_open,
732 	.release	= nvme_release,
733 	.getgeo		= nvme_getgeo,
734 	.revalidate_disk= nvme_revalidate_disk,
735 	.pr_ops		= &nvme_pr_ops,
736 };
737 
738 static int nvme_wait_ready(struct nvme_ctrl *ctrl, u64 cap, bool enabled)
739 {
740 	unsigned long timeout =
741 		((NVME_CAP_TIMEOUT(cap) + 1) * HZ / 2) + jiffies;
742 	u32 csts, bit = enabled ? NVME_CSTS_RDY : 0;
743 	int ret;
744 
745 	while ((ret = ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &csts)) == 0) {
746 		if ((csts & NVME_CSTS_RDY) == bit)
747 			break;
748 
749 		msleep(100);
750 		if (fatal_signal_pending(current))
751 			return -EINTR;
752 		if (time_after(jiffies, timeout)) {
753 			dev_err(ctrl->dev,
754 				"Device not ready; aborting %s\n", enabled ?
755 						"initialisation" : "reset");
756 			return -ENODEV;
757 		}
758 	}
759 
760 	return ret;
761 }
762 
763 /*
764  * If the device has been passed off to us in an enabled state, just clear
765  * the enabled bit.  The spec says we should set the 'shutdown notification
766  * bits', but doing so may cause the device to complete commands to the
767  * admin queue ... and we don't know what memory that might be pointing at!
768  */
769 int nvme_disable_ctrl(struct nvme_ctrl *ctrl, u64 cap)
770 {
771 	int ret;
772 
773 	ctrl->ctrl_config &= ~NVME_CC_SHN_MASK;
774 	ctrl->ctrl_config &= ~NVME_CC_ENABLE;
775 
776 	ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
777 	if (ret)
778 		return ret;
779 	return nvme_wait_ready(ctrl, cap, false);
780 }
781 
782 int nvme_enable_ctrl(struct nvme_ctrl *ctrl, u64 cap)
783 {
784 	/*
785 	 * Default to a 4K page size, with the intention to update this
786 	 * path in the future to accomodate architectures with differing
787 	 * kernel and IO page sizes.
788 	 */
789 	unsigned dev_page_min = NVME_CAP_MPSMIN(cap) + 12, page_shift = 12;
790 	int ret;
791 
792 	if (page_shift < dev_page_min) {
793 		dev_err(ctrl->dev,
794 			"Minimum device page size %u too large for host (%u)\n",
795 			1 << dev_page_min, 1 << page_shift);
796 		return -ENODEV;
797 	}
798 
799 	ctrl->page_size = 1 << page_shift;
800 
801 	ctrl->ctrl_config = NVME_CC_CSS_NVM;
802 	ctrl->ctrl_config |= (page_shift - 12) << NVME_CC_MPS_SHIFT;
803 	ctrl->ctrl_config |= NVME_CC_ARB_RR | NVME_CC_SHN_NONE;
804 	ctrl->ctrl_config |= NVME_CC_IOSQES | NVME_CC_IOCQES;
805 	ctrl->ctrl_config |= NVME_CC_ENABLE;
806 
807 	ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
808 	if (ret)
809 		return ret;
810 	return nvme_wait_ready(ctrl, cap, true);
811 }
812 
813 int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl)
814 {
815 	unsigned long timeout = SHUTDOWN_TIMEOUT + jiffies;
816 	u32 csts;
817 	int ret;
818 
819 	ctrl->ctrl_config &= ~NVME_CC_SHN_MASK;
820 	ctrl->ctrl_config |= NVME_CC_SHN_NORMAL;
821 
822 	ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
823 	if (ret)
824 		return ret;
825 
826 	while ((ret = ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &csts)) == 0) {
827 		if ((csts & NVME_CSTS_SHST_MASK) == NVME_CSTS_SHST_CMPLT)
828 			break;
829 
830 		msleep(100);
831 		if (fatal_signal_pending(current))
832 			return -EINTR;
833 		if (time_after(jiffies, timeout)) {
834 			dev_err(ctrl->dev,
835 				"Device shutdown incomplete; abort shutdown\n");
836 			return -ENODEV;
837 		}
838 	}
839 
840 	return ret;
841 }
842 
843 static void nvme_set_queue_limits(struct nvme_ctrl *ctrl,
844 		struct request_queue *q)
845 {
846 	if (ctrl->max_hw_sectors) {
847 		u32 max_segments =
848 			(ctrl->max_hw_sectors / (ctrl->page_size >> 9)) + 1;
849 
850 		blk_queue_max_hw_sectors(q, ctrl->max_hw_sectors);
851 		blk_queue_max_segments(q, min_t(u32, max_segments, USHRT_MAX));
852 	}
853 	if (ctrl->stripe_size)
854 		blk_queue_chunk_sectors(q, ctrl->stripe_size >> 9);
855 	if (ctrl->vwc & NVME_CTRL_VWC_PRESENT)
856 		blk_queue_flush(q, REQ_FLUSH | REQ_FUA);
857 	blk_queue_virt_boundary(q, ctrl->page_size - 1);
858 }
859 
860 /*
861  * Initialize the cached copies of the Identify data and various controller
862  * register in our nvme_ctrl structure.  This should be called as soon as
863  * the admin queue is fully up and running.
864  */
865 int nvme_init_identify(struct nvme_ctrl *ctrl)
866 {
867 	struct nvme_id_ctrl *id;
868 	u64 cap;
869 	int ret, page_shift;
870 
871 	ret = ctrl->ops->reg_read32(ctrl, NVME_REG_VS, &ctrl->vs);
872 	if (ret) {
873 		dev_err(ctrl->dev, "Reading VS failed (%d)\n", ret);
874 		return ret;
875 	}
876 
877 	ret = ctrl->ops->reg_read64(ctrl, NVME_REG_CAP, &cap);
878 	if (ret) {
879 		dev_err(ctrl->dev, "Reading CAP failed (%d)\n", ret);
880 		return ret;
881 	}
882 	page_shift = NVME_CAP_MPSMIN(cap) + 12;
883 
884 	if (ctrl->vs >= NVME_VS(1, 1))
885 		ctrl->subsystem = NVME_CAP_NSSRC(cap);
886 
887 	ret = nvme_identify_ctrl(ctrl, &id);
888 	if (ret) {
889 		dev_err(ctrl->dev, "Identify Controller failed (%d)\n", ret);
890 		return -EIO;
891 	}
892 
893 	ctrl->oncs = le16_to_cpup(&id->oncs);
894 	atomic_set(&ctrl->abort_limit, id->acl + 1);
895 	ctrl->vwc = id->vwc;
896 	memcpy(ctrl->serial, id->sn, sizeof(id->sn));
897 	memcpy(ctrl->model, id->mn, sizeof(id->mn));
898 	memcpy(ctrl->firmware_rev, id->fr, sizeof(id->fr));
899 	if (id->mdts)
900 		ctrl->max_hw_sectors = 1 << (id->mdts + page_shift - 9);
901 	else
902 		ctrl->max_hw_sectors = UINT_MAX;
903 
904 	if ((ctrl->quirks & NVME_QUIRK_STRIPE_SIZE) && id->vs[3]) {
905 		unsigned int max_hw_sectors;
906 
907 		ctrl->stripe_size = 1 << (id->vs[3] + page_shift);
908 		max_hw_sectors = ctrl->stripe_size >> (page_shift - 9);
909 		if (ctrl->max_hw_sectors) {
910 			ctrl->max_hw_sectors = min(max_hw_sectors,
911 							ctrl->max_hw_sectors);
912 		} else {
913 			ctrl->max_hw_sectors = max_hw_sectors;
914 		}
915 	}
916 
917 	nvme_set_queue_limits(ctrl, ctrl->admin_q);
918 
919 	kfree(id);
920 	return 0;
921 }
922 
923 static int nvme_dev_open(struct inode *inode, struct file *file)
924 {
925 	struct nvme_ctrl *ctrl;
926 	int instance = iminor(inode);
927 	int ret = -ENODEV;
928 
929 	spin_lock(&dev_list_lock);
930 	list_for_each_entry(ctrl, &nvme_ctrl_list, node) {
931 		if (ctrl->instance != instance)
932 			continue;
933 
934 		if (!ctrl->admin_q) {
935 			ret = -EWOULDBLOCK;
936 			break;
937 		}
938 		if (!kref_get_unless_zero(&ctrl->kref))
939 			break;
940 		file->private_data = ctrl;
941 		ret = 0;
942 		break;
943 	}
944 	spin_unlock(&dev_list_lock);
945 
946 	return ret;
947 }
948 
949 static int nvme_dev_release(struct inode *inode, struct file *file)
950 {
951 	nvme_put_ctrl(file->private_data);
952 	return 0;
953 }
954 
955 static int nvme_dev_user_cmd(struct nvme_ctrl *ctrl, void __user *argp)
956 {
957 	struct nvme_ns *ns;
958 	int ret;
959 
960 	mutex_lock(&ctrl->namespaces_mutex);
961 	if (list_empty(&ctrl->namespaces)) {
962 		ret = -ENOTTY;
963 		goto out_unlock;
964 	}
965 
966 	ns = list_first_entry(&ctrl->namespaces, struct nvme_ns, list);
967 	if (ns != list_last_entry(&ctrl->namespaces, struct nvme_ns, list)) {
968 		dev_warn(ctrl->dev,
969 			"NVME_IOCTL_IO_CMD not supported when multiple namespaces present!\n");
970 		ret = -EINVAL;
971 		goto out_unlock;
972 	}
973 
974 	dev_warn(ctrl->dev,
975 		"using deprecated NVME_IOCTL_IO_CMD ioctl on the char device!\n");
976 	kref_get(&ns->kref);
977 	mutex_unlock(&ctrl->namespaces_mutex);
978 
979 	ret = nvme_user_cmd(ctrl, ns, argp);
980 	nvme_put_ns(ns);
981 	return ret;
982 
983 out_unlock:
984 	mutex_unlock(&ctrl->namespaces_mutex);
985 	return ret;
986 }
987 
988 static long nvme_dev_ioctl(struct file *file, unsigned int cmd,
989 		unsigned long arg)
990 {
991 	struct nvme_ctrl *ctrl = file->private_data;
992 	void __user *argp = (void __user *)arg;
993 
994 	switch (cmd) {
995 	case NVME_IOCTL_ADMIN_CMD:
996 		return nvme_user_cmd(ctrl, NULL, argp);
997 	case NVME_IOCTL_IO_CMD:
998 		return nvme_dev_user_cmd(ctrl, argp);
999 	case NVME_IOCTL_RESET:
1000 		dev_warn(ctrl->dev, "resetting controller\n");
1001 		return ctrl->ops->reset_ctrl(ctrl);
1002 	case NVME_IOCTL_SUBSYS_RESET:
1003 		return nvme_reset_subsystem(ctrl);
1004 	default:
1005 		return -ENOTTY;
1006 	}
1007 }
1008 
1009 static const struct file_operations nvme_dev_fops = {
1010 	.owner		= THIS_MODULE,
1011 	.open		= nvme_dev_open,
1012 	.release	= nvme_dev_release,
1013 	.unlocked_ioctl	= nvme_dev_ioctl,
1014 	.compat_ioctl	= nvme_dev_ioctl,
1015 };
1016 
1017 static ssize_t nvme_sysfs_reset(struct device *dev,
1018 				struct device_attribute *attr, const char *buf,
1019 				size_t count)
1020 {
1021 	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
1022 	int ret;
1023 
1024 	ret = ctrl->ops->reset_ctrl(ctrl);
1025 	if (ret < 0)
1026 		return ret;
1027 	return count;
1028 }
1029 static DEVICE_ATTR(reset_controller, S_IWUSR, NULL, nvme_sysfs_reset);
1030 
1031 static ssize_t uuid_show(struct device *dev, struct device_attribute *attr,
1032 								char *buf)
1033 {
1034 	struct nvme_ns *ns = dev_to_disk(dev)->private_data;
1035 	return sprintf(buf, "%pU\n", ns->uuid);
1036 }
1037 static DEVICE_ATTR(uuid, S_IRUGO, uuid_show, NULL);
1038 
1039 static ssize_t eui_show(struct device *dev, struct device_attribute *attr,
1040 								char *buf)
1041 {
1042 	struct nvme_ns *ns = dev_to_disk(dev)->private_data;
1043 	return sprintf(buf, "%8phd\n", ns->eui);
1044 }
1045 static DEVICE_ATTR(eui, S_IRUGO, eui_show, NULL);
1046 
1047 static ssize_t nsid_show(struct device *dev, struct device_attribute *attr,
1048 								char *buf)
1049 {
1050 	struct nvme_ns *ns = dev_to_disk(dev)->private_data;
1051 	return sprintf(buf, "%d\n", ns->ns_id);
1052 }
1053 static DEVICE_ATTR(nsid, S_IRUGO, nsid_show, NULL);
1054 
1055 static struct attribute *nvme_ns_attrs[] = {
1056 	&dev_attr_uuid.attr,
1057 	&dev_attr_eui.attr,
1058 	&dev_attr_nsid.attr,
1059 	NULL,
1060 };
1061 
1062 static umode_t nvme_attrs_are_visible(struct kobject *kobj,
1063 		struct attribute *a, int n)
1064 {
1065 	struct device *dev = container_of(kobj, struct device, kobj);
1066 	struct nvme_ns *ns = dev_to_disk(dev)->private_data;
1067 
1068 	if (a == &dev_attr_uuid.attr) {
1069 		if (!memchr_inv(ns->uuid, 0, sizeof(ns->uuid)))
1070 			return 0;
1071 	}
1072 	if (a == &dev_attr_eui.attr) {
1073 		if (!memchr_inv(ns->eui, 0, sizeof(ns->eui)))
1074 			return 0;
1075 	}
1076 	return a->mode;
1077 }
1078 
1079 static const struct attribute_group nvme_ns_attr_group = {
1080 	.attrs		= nvme_ns_attrs,
1081 	.is_visible	= nvme_attrs_are_visible,
1082 };
1083 
1084 #define nvme_show_function(field)						\
1085 static ssize_t  field##_show(struct device *dev,				\
1086 			    struct device_attribute *attr, char *buf)		\
1087 {										\
1088         struct nvme_ctrl *ctrl = dev_get_drvdata(dev);				\
1089         return sprintf(buf, "%.*s\n", (int)sizeof(ctrl->field), ctrl->field);	\
1090 }										\
1091 static DEVICE_ATTR(field, S_IRUGO, field##_show, NULL);
1092 
1093 nvme_show_function(model);
1094 nvme_show_function(serial);
1095 nvme_show_function(firmware_rev);
1096 
1097 static struct attribute *nvme_dev_attrs[] = {
1098 	&dev_attr_reset_controller.attr,
1099 	&dev_attr_model.attr,
1100 	&dev_attr_serial.attr,
1101 	&dev_attr_firmware_rev.attr,
1102 	NULL
1103 };
1104 
1105 static struct attribute_group nvme_dev_attrs_group = {
1106 	.attrs = nvme_dev_attrs,
1107 };
1108 
1109 static const struct attribute_group *nvme_dev_attr_groups[] = {
1110 	&nvme_dev_attrs_group,
1111 	NULL,
1112 };
1113 
1114 static int ns_cmp(void *priv, struct list_head *a, struct list_head *b)
1115 {
1116 	struct nvme_ns *nsa = container_of(a, struct nvme_ns, list);
1117 	struct nvme_ns *nsb = container_of(b, struct nvme_ns, list);
1118 
1119 	return nsa->ns_id - nsb->ns_id;
1120 }
1121 
1122 static struct nvme_ns *nvme_find_ns(struct nvme_ctrl *ctrl, unsigned nsid)
1123 {
1124 	struct nvme_ns *ns;
1125 
1126 	lockdep_assert_held(&ctrl->namespaces_mutex);
1127 
1128 	list_for_each_entry(ns, &ctrl->namespaces, list) {
1129 		if (ns->ns_id == nsid)
1130 			return ns;
1131 		if (ns->ns_id > nsid)
1132 			break;
1133 	}
1134 	return NULL;
1135 }
1136 
1137 static void nvme_alloc_ns(struct nvme_ctrl *ctrl, unsigned nsid)
1138 {
1139 	struct nvme_ns *ns;
1140 	struct gendisk *disk;
1141 	int node = dev_to_node(ctrl->dev);
1142 
1143 	lockdep_assert_held(&ctrl->namespaces_mutex);
1144 
1145 	ns = kzalloc_node(sizeof(*ns), GFP_KERNEL, node);
1146 	if (!ns)
1147 		return;
1148 
1149 	ns->instance = ida_simple_get(&ctrl->ns_ida, 1, 0, GFP_KERNEL);
1150 	if (ns->instance < 0)
1151 		goto out_free_ns;
1152 
1153 	ns->queue = blk_mq_init_queue(ctrl->tagset);
1154 	if (IS_ERR(ns->queue))
1155 		goto out_release_instance;
1156 	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, ns->queue);
1157 	ns->queue->queuedata = ns;
1158 	ns->ctrl = ctrl;
1159 
1160 	disk = alloc_disk_node(0, node);
1161 	if (!disk)
1162 		goto out_free_queue;
1163 
1164 	kref_init(&ns->kref);
1165 	ns->ns_id = nsid;
1166 	ns->disk = disk;
1167 	ns->lba_shift = 9; /* set to a default value for 512 until disk is validated */
1168 
1169 
1170 	blk_queue_logical_block_size(ns->queue, 1 << ns->lba_shift);
1171 	nvme_set_queue_limits(ctrl, ns->queue);
1172 
1173 	disk->major = nvme_major;
1174 	disk->first_minor = 0;
1175 	disk->fops = &nvme_fops;
1176 	disk->private_data = ns;
1177 	disk->queue = ns->queue;
1178 	disk->driverfs_dev = ctrl->device;
1179 	disk->flags = GENHD_FL_EXT_DEVT;
1180 	sprintf(disk->disk_name, "nvme%dn%d", ctrl->instance, ns->instance);
1181 
1182 	if (nvme_revalidate_disk(ns->disk))
1183 		goto out_free_disk;
1184 
1185 	list_add_tail(&ns->list, &ctrl->namespaces);
1186 	kref_get(&ctrl->kref);
1187 	if (ns->type == NVME_NS_LIGHTNVM)
1188 		return;
1189 
1190 	add_disk(ns->disk);
1191 	if (sysfs_create_group(&disk_to_dev(ns->disk)->kobj,
1192 					&nvme_ns_attr_group))
1193 		pr_warn("%s: failed to create sysfs group for identification\n",
1194 			ns->disk->disk_name);
1195 	return;
1196  out_free_disk:
1197 	kfree(disk);
1198  out_free_queue:
1199 	blk_cleanup_queue(ns->queue);
1200  out_release_instance:
1201 	ida_simple_remove(&ctrl->ns_ida, ns->instance);
1202  out_free_ns:
1203 	kfree(ns);
1204 }
1205 
1206 static void nvme_ns_remove(struct nvme_ns *ns)
1207 {
1208 	if (test_and_set_bit(NVME_NS_REMOVING, &ns->flags))
1209 		return;
1210 
1211 	if (ns->disk->flags & GENHD_FL_UP) {
1212 		if (blk_get_integrity(ns->disk))
1213 			blk_integrity_unregister(ns->disk);
1214 		sysfs_remove_group(&disk_to_dev(ns->disk)->kobj,
1215 					&nvme_ns_attr_group);
1216 		del_gendisk(ns->disk);
1217 		blk_mq_abort_requeue_list(ns->queue);
1218 		blk_cleanup_queue(ns->queue);
1219 	}
1220 	mutex_lock(&ns->ctrl->namespaces_mutex);
1221 	list_del_init(&ns->list);
1222 	mutex_unlock(&ns->ctrl->namespaces_mutex);
1223 	nvme_put_ns(ns);
1224 }
1225 
1226 static void nvme_validate_ns(struct nvme_ctrl *ctrl, unsigned nsid)
1227 {
1228 	struct nvme_ns *ns;
1229 
1230 	ns = nvme_find_ns(ctrl, nsid);
1231 	if (ns) {
1232 		if (revalidate_disk(ns->disk))
1233 			nvme_ns_remove(ns);
1234 	} else
1235 		nvme_alloc_ns(ctrl, nsid);
1236 }
1237 
1238 static int nvme_scan_ns_list(struct nvme_ctrl *ctrl, unsigned nn)
1239 {
1240 	struct nvme_ns *ns;
1241 	__le32 *ns_list;
1242 	unsigned i, j, nsid, prev = 0, num_lists = DIV_ROUND_UP(nn, 1024);
1243 	int ret = 0;
1244 
1245 	ns_list = kzalloc(0x1000, GFP_KERNEL);
1246 	if (!ns_list)
1247 		return -ENOMEM;
1248 
1249 	for (i = 0; i < num_lists; i++) {
1250 		ret = nvme_identify_ns_list(ctrl, prev, ns_list);
1251 		if (ret)
1252 			goto out;
1253 
1254 		for (j = 0; j < min(nn, 1024U); j++) {
1255 			nsid = le32_to_cpu(ns_list[j]);
1256 			if (!nsid)
1257 				goto out;
1258 
1259 			nvme_validate_ns(ctrl, nsid);
1260 
1261 			while (++prev < nsid) {
1262 				ns = nvme_find_ns(ctrl, prev);
1263 				if (ns)
1264 					nvme_ns_remove(ns);
1265 			}
1266 		}
1267 		nn -= j;
1268 	}
1269  out:
1270 	kfree(ns_list);
1271 	return ret;
1272 }
1273 
1274 static void __nvme_scan_namespaces(struct nvme_ctrl *ctrl, unsigned nn)
1275 {
1276 	struct nvme_ns *ns, *next;
1277 	unsigned i;
1278 
1279 	lockdep_assert_held(&ctrl->namespaces_mutex);
1280 
1281 	for (i = 1; i <= nn; i++)
1282 		nvme_validate_ns(ctrl, i);
1283 
1284 	list_for_each_entry_safe(ns, next, &ctrl->namespaces, list) {
1285 		if (ns->ns_id > nn)
1286 			nvme_ns_remove(ns);
1287 	}
1288 }
1289 
1290 void nvme_scan_namespaces(struct nvme_ctrl *ctrl)
1291 {
1292 	struct nvme_id_ctrl *id;
1293 	unsigned nn;
1294 
1295 	if (nvme_identify_ctrl(ctrl, &id))
1296 		return;
1297 
1298 	mutex_lock(&ctrl->namespaces_mutex);
1299 	nn = le32_to_cpu(id->nn);
1300 	if (ctrl->vs >= NVME_VS(1, 1) &&
1301 	    !(ctrl->quirks & NVME_QUIRK_IDENTIFY_CNS)) {
1302 		if (!nvme_scan_ns_list(ctrl, nn))
1303 			goto done;
1304 	}
1305 	__nvme_scan_namespaces(ctrl, le32_to_cpup(&id->nn));
1306  done:
1307 	list_sort(NULL, &ctrl->namespaces, ns_cmp);
1308 	mutex_unlock(&ctrl->namespaces_mutex);
1309 	kfree(id);
1310 }
1311 
1312 void nvme_remove_namespaces(struct nvme_ctrl *ctrl)
1313 {
1314 	struct nvme_ns *ns, *next;
1315 
1316 	list_for_each_entry_safe(ns, next, &ctrl->namespaces, list)
1317 		nvme_ns_remove(ns);
1318 }
1319 
1320 static DEFINE_IDA(nvme_instance_ida);
1321 
1322 static int nvme_set_instance(struct nvme_ctrl *ctrl)
1323 {
1324 	int instance, error;
1325 
1326 	do {
1327 		if (!ida_pre_get(&nvme_instance_ida, GFP_KERNEL))
1328 			return -ENODEV;
1329 
1330 		spin_lock(&dev_list_lock);
1331 		error = ida_get_new(&nvme_instance_ida, &instance);
1332 		spin_unlock(&dev_list_lock);
1333 	} while (error == -EAGAIN);
1334 
1335 	if (error)
1336 		return -ENODEV;
1337 
1338 	ctrl->instance = instance;
1339 	return 0;
1340 }
1341 
1342 static void nvme_release_instance(struct nvme_ctrl *ctrl)
1343 {
1344 	spin_lock(&dev_list_lock);
1345 	ida_remove(&nvme_instance_ida, ctrl->instance);
1346 	spin_unlock(&dev_list_lock);
1347 }
1348 
1349 void nvme_uninit_ctrl(struct nvme_ctrl *ctrl)
1350  {
1351 	device_destroy(nvme_class, MKDEV(nvme_char_major, ctrl->instance));
1352 
1353 	spin_lock(&dev_list_lock);
1354 	list_del(&ctrl->node);
1355 	spin_unlock(&dev_list_lock);
1356 }
1357 
1358 static void nvme_free_ctrl(struct kref *kref)
1359 {
1360 	struct nvme_ctrl *ctrl = container_of(kref, struct nvme_ctrl, kref);
1361 
1362 	put_device(ctrl->device);
1363 	nvme_release_instance(ctrl);
1364 	ida_destroy(&ctrl->ns_ida);
1365 
1366 	ctrl->ops->free_ctrl(ctrl);
1367 }
1368 
1369 void nvme_put_ctrl(struct nvme_ctrl *ctrl)
1370 {
1371 	kref_put(&ctrl->kref, nvme_free_ctrl);
1372 }
1373 
1374 /*
1375  * Initialize a NVMe controller structures.  This needs to be called during
1376  * earliest initialization so that we have the initialized structured around
1377  * during probing.
1378  */
1379 int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
1380 		const struct nvme_ctrl_ops *ops, unsigned long quirks)
1381 {
1382 	int ret;
1383 
1384 	INIT_LIST_HEAD(&ctrl->namespaces);
1385 	mutex_init(&ctrl->namespaces_mutex);
1386 	kref_init(&ctrl->kref);
1387 	ctrl->dev = dev;
1388 	ctrl->ops = ops;
1389 	ctrl->quirks = quirks;
1390 
1391 	ret = nvme_set_instance(ctrl);
1392 	if (ret)
1393 		goto out;
1394 
1395 	ctrl->device = device_create_with_groups(nvme_class, ctrl->dev,
1396 				MKDEV(nvme_char_major, ctrl->instance),
1397 				dev, nvme_dev_attr_groups,
1398 				"nvme%d", ctrl->instance);
1399 	if (IS_ERR(ctrl->device)) {
1400 		ret = PTR_ERR(ctrl->device);
1401 		goto out_release_instance;
1402 	}
1403 	get_device(ctrl->device);
1404 	dev_set_drvdata(ctrl->device, ctrl);
1405 	ida_init(&ctrl->ns_ida);
1406 
1407 	spin_lock(&dev_list_lock);
1408 	list_add_tail(&ctrl->node, &nvme_ctrl_list);
1409 	spin_unlock(&dev_list_lock);
1410 
1411 	return 0;
1412 out_release_instance:
1413 	nvme_release_instance(ctrl);
1414 out:
1415 	return ret;
1416 }
1417 
1418 /**
1419  * nvme_kill_queues(): Ends all namespace queues
1420  * @ctrl: the dead controller that needs to end
1421  *
1422  * Call this function when the driver determines it is unable to get the
1423  * controller in a state capable of servicing IO.
1424  */
1425 void nvme_kill_queues(struct nvme_ctrl *ctrl)
1426 {
1427 	struct nvme_ns *ns;
1428 
1429 	mutex_lock(&ctrl->namespaces_mutex);
1430 	list_for_each_entry(ns, &ctrl->namespaces, list) {
1431 		if (!kref_get_unless_zero(&ns->kref))
1432 			continue;
1433 
1434 		/*
1435 		 * Revalidating a dead namespace sets capacity to 0. This will
1436 		 * end buffered writers dirtying pages that can't be synced.
1437 		 */
1438 		if (!test_and_set_bit(NVME_NS_DEAD, &ns->flags))
1439 			revalidate_disk(ns->disk);
1440 
1441 		blk_set_queue_dying(ns->queue);
1442 		blk_mq_abort_requeue_list(ns->queue);
1443 		blk_mq_start_stopped_hw_queues(ns->queue, true);
1444 
1445 		nvme_put_ns(ns);
1446 	}
1447 	mutex_unlock(&ctrl->namespaces_mutex);
1448 }
1449 
1450 void nvme_stop_queues(struct nvme_ctrl *ctrl)
1451 {
1452 	struct nvme_ns *ns;
1453 
1454 	mutex_lock(&ctrl->namespaces_mutex);
1455 	list_for_each_entry(ns, &ctrl->namespaces, list) {
1456 		spin_lock_irq(ns->queue->queue_lock);
1457 		queue_flag_set(QUEUE_FLAG_STOPPED, ns->queue);
1458 		spin_unlock_irq(ns->queue->queue_lock);
1459 
1460 		blk_mq_cancel_requeue_work(ns->queue);
1461 		blk_mq_stop_hw_queues(ns->queue);
1462 	}
1463 	mutex_unlock(&ctrl->namespaces_mutex);
1464 }
1465 
1466 void nvme_start_queues(struct nvme_ctrl *ctrl)
1467 {
1468 	struct nvme_ns *ns;
1469 
1470 	mutex_lock(&ctrl->namespaces_mutex);
1471 	list_for_each_entry(ns, &ctrl->namespaces, list) {
1472 		queue_flag_clear_unlocked(QUEUE_FLAG_STOPPED, ns->queue);
1473 		blk_mq_start_stopped_hw_queues(ns->queue, true);
1474 		blk_mq_kick_requeue_list(ns->queue);
1475 	}
1476 	mutex_unlock(&ctrl->namespaces_mutex);
1477 }
1478 
1479 int __init nvme_core_init(void)
1480 {
1481 	int result;
1482 
1483 	result = register_blkdev(nvme_major, "nvme");
1484 	if (result < 0)
1485 		return result;
1486 	else if (result > 0)
1487 		nvme_major = result;
1488 
1489 	result = __register_chrdev(nvme_char_major, 0, NVME_MINORS, "nvme",
1490 							&nvme_dev_fops);
1491 	if (result < 0)
1492 		goto unregister_blkdev;
1493 	else if (result > 0)
1494 		nvme_char_major = result;
1495 
1496 	nvme_class = class_create(THIS_MODULE, "nvme");
1497 	if (IS_ERR(nvme_class)) {
1498 		result = PTR_ERR(nvme_class);
1499 		goto unregister_chrdev;
1500 	}
1501 
1502 	return 0;
1503 
1504  unregister_chrdev:
1505 	__unregister_chrdev(nvme_char_major, 0, NVME_MINORS, "nvme");
1506  unregister_blkdev:
1507 	unregister_blkdev(nvme_major, "nvme");
1508 	return result;
1509 }
1510 
1511 void nvme_core_exit(void)
1512 {
1513 	unregister_blkdev(nvme_major, "nvme");
1514 	class_destroy(nvme_class);
1515 	__unregister_chrdev(nvme_char_major, 0, NVME_MINORS, "nvme");
1516 }
1517