Merge branch 'for-4.8/core' of git://git.kernel.dk/linux-block
[karo-tx-linux.git] / drivers / nvme / host / core.c
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_op(req) == REQ_OP_FLUSH)
294                 nvme_setup_flush(ns, cmd);
295         else if (req_op(req) == REQ_OP_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_get_ns(struct nvme_ctrl *ctrl, unsigned nsid)
1398 {
1399         struct nvme_ns *ns, *ret = NULL;
1400
1401         mutex_lock(&ctrl->namespaces_mutex);
1402         list_for_each_entry(ns, &ctrl->namespaces, list) {
1403                 if (ns->ns_id == nsid) {
1404                         kref_get(&ns->kref);
1405                         ret = ns;
1406                         break;
1407                 }
1408                 if (ns->ns_id > nsid)
1409                         break;
1410         }
1411         mutex_unlock(&ctrl->namespaces_mutex);
1412         return ret;
1413 }
1414
1415 static void nvme_alloc_ns(struct nvme_ctrl *ctrl, unsigned nsid)
1416 {
1417         struct nvme_ns *ns;
1418         struct gendisk *disk;
1419         int node = dev_to_node(ctrl->dev);
1420
1421         ns = kzalloc_node(sizeof(*ns), GFP_KERNEL, node);
1422         if (!ns)
1423                 return;
1424
1425         ns->instance = ida_simple_get(&ctrl->ns_ida, 1, 0, GFP_KERNEL);
1426         if (ns->instance < 0)
1427                 goto out_free_ns;
1428
1429         ns->queue = blk_mq_init_queue(ctrl->tagset);
1430         if (IS_ERR(ns->queue))
1431                 goto out_release_instance;
1432         queue_flag_set_unlocked(QUEUE_FLAG_NONROT, ns->queue);
1433         ns->queue->queuedata = ns;
1434         ns->ctrl = ctrl;
1435
1436         disk = alloc_disk_node(0, node);
1437         if (!disk)
1438                 goto out_free_queue;
1439
1440         kref_init(&ns->kref);
1441         ns->ns_id = nsid;
1442         ns->disk = disk;
1443         ns->lba_shift = 9; /* set to a default value for 512 until disk is validated */
1444
1445
1446         blk_queue_logical_block_size(ns->queue, 1 << ns->lba_shift);
1447         nvme_set_queue_limits(ctrl, ns->queue);
1448
1449         disk->major = nvme_major;
1450         disk->first_minor = 0;
1451         disk->fops = &nvme_fops;
1452         disk->private_data = ns;
1453         disk->queue = ns->queue;
1454         disk->driverfs_dev = ctrl->device;
1455         disk->flags = GENHD_FL_EXT_DEVT;
1456         sprintf(disk->disk_name, "nvme%dn%d", ctrl->instance, ns->instance);
1457
1458         if (nvme_revalidate_disk(ns->disk))
1459                 goto out_free_disk;
1460
1461         mutex_lock(&ctrl->namespaces_mutex);
1462         list_add_tail(&ns->list, &ctrl->namespaces);
1463         mutex_unlock(&ctrl->namespaces_mutex);
1464
1465         kref_get(&ctrl->kref);
1466         if (ns->type == NVME_NS_LIGHTNVM)
1467                 return;
1468
1469         add_disk(ns->disk);
1470         if (sysfs_create_group(&disk_to_dev(ns->disk)->kobj,
1471                                         &nvme_ns_attr_group))
1472                 pr_warn("%s: failed to create sysfs group for identification\n",
1473                         ns->disk->disk_name);
1474         return;
1475  out_free_disk:
1476         kfree(disk);
1477  out_free_queue:
1478         blk_cleanup_queue(ns->queue);
1479  out_release_instance:
1480         ida_simple_remove(&ctrl->ns_ida, ns->instance);
1481  out_free_ns:
1482         kfree(ns);
1483 }
1484
1485 static void nvme_ns_remove(struct nvme_ns *ns)
1486 {
1487         if (test_and_set_bit(NVME_NS_REMOVING, &ns->flags))
1488                 return;
1489
1490         if (ns->disk->flags & GENHD_FL_UP) {
1491                 if (blk_get_integrity(ns->disk))
1492                         blk_integrity_unregister(ns->disk);
1493                 sysfs_remove_group(&disk_to_dev(ns->disk)->kobj,
1494                                         &nvme_ns_attr_group);
1495                 del_gendisk(ns->disk);
1496                 blk_mq_abort_requeue_list(ns->queue);
1497                 blk_cleanup_queue(ns->queue);
1498         }
1499
1500         mutex_lock(&ns->ctrl->namespaces_mutex);
1501         list_del_init(&ns->list);
1502         mutex_unlock(&ns->ctrl->namespaces_mutex);
1503
1504         nvme_put_ns(ns);
1505 }
1506
1507 static void nvme_validate_ns(struct nvme_ctrl *ctrl, unsigned nsid)
1508 {
1509         struct nvme_ns *ns;
1510
1511         ns = nvme_find_get_ns(ctrl, nsid);
1512         if (ns) {
1513                 if (revalidate_disk(ns->disk))
1514                         nvme_ns_remove(ns);
1515                 nvme_put_ns(ns);
1516         } else
1517                 nvme_alloc_ns(ctrl, nsid);
1518 }
1519
1520 static int nvme_scan_ns_list(struct nvme_ctrl *ctrl, unsigned nn)
1521 {
1522         struct nvme_ns *ns;
1523         __le32 *ns_list;
1524         unsigned i, j, nsid, prev = 0, num_lists = DIV_ROUND_UP(nn, 1024);
1525         int ret = 0;
1526
1527         ns_list = kzalloc(0x1000, GFP_KERNEL);
1528         if (!ns_list)
1529                 return -ENOMEM;
1530
1531         for (i = 0; i < num_lists; i++) {
1532                 ret = nvme_identify_ns_list(ctrl, prev, ns_list);
1533                 if (ret)
1534                         goto out;
1535
1536                 for (j = 0; j < min(nn, 1024U); j++) {
1537                         nsid = le32_to_cpu(ns_list[j]);
1538                         if (!nsid)
1539                                 goto out;
1540
1541                         nvme_validate_ns(ctrl, nsid);
1542
1543                         while (++prev < nsid) {
1544                                 ns = nvme_find_get_ns(ctrl, prev);
1545                                 if (ns) {
1546                                         nvme_ns_remove(ns);
1547                                         nvme_put_ns(ns);
1548                                 }
1549                         }
1550                 }
1551                 nn -= j;
1552         }
1553  out:
1554         kfree(ns_list);
1555         return ret;
1556 }
1557
1558 static void nvme_scan_ns_sequential(struct nvme_ctrl *ctrl, unsigned nn)
1559 {
1560         struct nvme_ns *ns, *next;
1561         unsigned i;
1562
1563         for (i = 1; i <= nn; i++)
1564                 nvme_validate_ns(ctrl, i);
1565
1566         list_for_each_entry_safe(ns, next, &ctrl->namespaces, list) {
1567                 if (ns->ns_id > nn)
1568                         nvme_ns_remove(ns);
1569         }
1570 }
1571
1572 static void nvme_scan_work(struct work_struct *work)
1573 {
1574         struct nvme_ctrl *ctrl =
1575                 container_of(work, struct nvme_ctrl, scan_work);
1576         struct nvme_id_ctrl *id;
1577         unsigned nn;
1578
1579         if (ctrl->state != NVME_CTRL_LIVE)
1580                 return;
1581
1582         if (nvme_identify_ctrl(ctrl, &id))
1583                 return;
1584
1585         nn = le32_to_cpu(id->nn);
1586         if (ctrl->vs >= NVME_VS(1, 1) &&
1587             !(ctrl->quirks & NVME_QUIRK_IDENTIFY_CNS)) {
1588                 if (!nvme_scan_ns_list(ctrl, nn))
1589                         goto done;
1590         }
1591         nvme_scan_ns_sequential(ctrl, nn);
1592  done:
1593         mutex_lock(&ctrl->namespaces_mutex);
1594         list_sort(NULL, &ctrl->namespaces, ns_cmp);
1595         mutex_unlock(&ctrl->namespaces_mutex);
1596         kfree(id);
1597
1598         if (ctrl->ops->post_scan)
1599                 ctrl->ops->post_scan(ctrl);
1600 }
1601
1602 void nvme_queue_scan(struct nvme_ctrl *ctrl)
1603 {
1604         /*
1605          * Do not queue new scan work when a controller is reset during
1606          * removal.
1607          */
1608         if (ctrl->state == NVME_CTRL_LIVE)
1609                 schedule_work(&ctrl->scan_work);
1610 }
1611 EXPORT_SYMBOL_GPL(nvme_queue_scan);
1612
1613 /*
1614  * This function iterates the namespace list unlocked to allow recovery from
1615  * controller failure. It is up to the caller to ensure the namespace list is
1616  * not modified by scan work while this function is executing.
1617  */
1618 void nvme_remove_namespaces(struct nvme_ctrl *ctrl)
1619 {
1620         struct nvme_ns *ns, *next;
1621
1622         /*
1623          * The dead states indicates the controller was not gracefully
1624          * disconnected. In that case, we won't be able to flush any data while
1625          * removing the namespaces' disks; fail all the queues now to avoid
1626          * potentially having to clean up the failed sync later.
1627          */
1628         if (ctrl->state == NVME_CTRL_DEAD)
1629                 nvme_kill_queues(ctrl);
1630
1631         list_for_each_entry_safe(ns, next, &ctrl->namespaces, list)
1632                 nvme_ns_remove(ns);
1633 }
1634 EXPORT_SYMBOL_GPL(nvme_remove_namespaces);
1635
1636 static void nvme_async_event_work(struct work_struct *work)
1637 {
1638         struct nvme_ctrl *ctrl =
1639                 container_of(work, struct nvme_ctrl, async_event_work);
1640
1641         spin_lock_irq(&ctrl->lock);
1642         while (ctrl->event_limit > 0) {
1643                 int aer_idx = --ctrl->event_limit;
1644
1645                 spin_unlock_irq(&ctrl->lock);
1646                 ctrl->ops->submit_async_event(ctrl, aer_idx);
1647                 spin_lock_irq(&ctrl->lock);
1648         }
1649         spin_unlock_irq(&ctrl->lock);
1650 }
1651
1652 void nvme_complete_async_event(struct nvme_ctrl *ctrl,
1653                 struct nvme_completion *cqe)
1654 {
1655         u16 status = le16_to_cpu(cqe->status) >> 1;
1656         u32 result = le32_to_cpu(cqe->result);
1657
1658         if (status == NVME_SC_SUCCESS || status == NVME_SC_ABORT_REQ) {
1659                 ++ctrl->event_limit;
1660                 schedule_work(&ctrl->async_event_work);
1661         }
1662
1663         if (status != NVME_SC_SUCCESS)
1664                 return;
1665
1666         switch (result & 0xff07) {
1667         case NVME_AER_NOTICE_NS_CHANGED:
1668                 dev_info(ctrl->device, "rescanning\n");
1669                 nvme_queue_scan(ctrl);
1670                 break;
1671         default:
1672                 dev_warn(ctrl->device, "async event result %08x\n", result);
1673         }
1674 }
1675 EXPORT_SYMBOL_GPL(nvme_complete_async_event);
1676
1677 void nvme_queue_async_events(struct nvme_ctrl *ctrl)
1678 {
1679         ctrl->event_limit = NVME_NR_AERS;
1680         schedule_work(&ctrl->async_event_work);
1681 }
1682 EXPORT_SYMBOL_GPL(nvme_queue_async_events);
1683
1684 static DEFINE_IDA(nvme_instance_ida);
1685
1686 static int nvme_set_instance(struct nvme_ctrl *ctrl)
1687 {
1688         int instance, error;
1689
1690         do {
1691                 if (!ida_pre_get(&nvme_instance_ida, GFP_KERNEL))
1692                         return -ENODEV;
1693
1694                 spin_lock(&dev_list_lock);
1695                 error = ida_get_new(&nvme_instance_ida, &instance);
1696                 spin_unlock(&dev_list_lock);
1697         } while (error == -EAGAIN);
1698
1699         if (error)
1700                 return -ENODEV;
1701
1702         ctrl->instance = instance;
1703         return 0;
1704 }
1705
1706 static void nvme_release_instance(struct nvme_ctrl *ctrl)
1707 {
1708         spin_lock(&dev_list_lock);
1709         ida_remove(&nvme_instance_ida, ctrl->instance);
1710         spin_unlock(&dev_list_lock);
1711 }
1712
1713 void nvme_uninit_ctrl(struct nvme_ctrl *ctrl)
1714 {
1715         flush_work(&ctrl->async_event_work);
1716         flush_work(&ctrl->scan_work);
1717         nvme_remove_namespaces(ctrl);
1718
1719         device_destroy(nvme_class, MKDEV(nvme_char_major, ctrl->instance));
1720
1721         spin_lock(&dev_list_lock);
1722         list_del(&ctrl->node);
1723         spin_unlock(&dev_list_lock);
1724 }
1725 EXPORT_SYMBOL_GPL(nvme_uninit_ctrl);
1726
1727 static void nvme_free_ctrl(struct kref *kref)
1728 {
1729         struct nvme_ctrl *ctrl = container_of(kref, struct nvme_ctrl, kref);
1730
1731         put_device(ctrl->device);
1732         nvme_release_instance(ctrl);
1733         ida_destroy(&ctrl->ns_ida);
1734
1735         ctrl->ops->free_ctrl(ctrl);
1736 }
1737
1738 void nvme_put_ctrl(struct nvme_ctrl *ctrl)
1739 {
1740         kref_put(&ctrl->kref, nvme_free_ctrl);
1741 }
1742 EXPORT_SYMBOL_GPL(nvme_put_ctrl);
1743
1744 /*
1745  * Initialize a NVMe controller structures.  This needs to be called during
1746  * earliest initialization so that we have the initialized structured around
1747  * during probing.
1748  */
1749 int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
1750                 const struct nvme_ctrl_ops *ops, unsigned long quirks)
1751 {
1752         int ret;
1753
1754         ctrl->state = NVME_CTRL_NEW;
1755         spin_lock_init(&ctrl->lock);
1756         INIT_LIST_HEAD(&ctrl->namespaces);
1757         mutex_init(&ctrl->namespaces_mutex);
1758         kref_init(&ctrl->kref);
1759         ctrl->dev = dev;
1760         ctrl->ops = ops;
1761         ctrl->quirks = quirks;
1762         INIT_WORK(&ctrl->scan_work, nvme_scan_work);
1763         INIT_WORK(&ctrl->async_event_work, nvme_async_event_work);
1764
1765         ret = nvme_set_instance(ctrl);
1766         if (ret)
1767                 goto out;
1768
1769         ctrl->device = device_create_with_groups(nvme_class, ctrl->dev,
1770                                 MKDEV(nvme_char_major, ctrl->instance),
1771                                 ctrl, nvme_dev_attr_groups,
1772                                 "nvme%d", ctrl->instance);
1773         if (IS_ERR(ctrl->device)) {
1774                 ret = PTR_ERR(ctrl->device);
1775                 goto out_release_instance;
1776         }
1777         get_device(ctrl->device);
1778         ida_init(&ctrl->ns_ida);
1779
1780         spin_lock(&dev_list_lock);
1781         list_add_tail(&ctrl->node, &nvme_ctrl_list);
1782         spin_unlock(&dev_list_lock);
1783
1784         return 0;
1785 out_release_instance:
1786         nvme_release_instance(ctrl);
1787 out:
1788         return ret;
1789 }
1790 EXPORT_SYMBOL_GPL(nvme_init_ctrl);
1791
1792 /**
1793  * nvme_kill_queues(): Ends all namespace queues
1794  * @ctrl: the dead controller that needs to end
1795  *
1796  * Call this function when the driver determines it is unable to get the
1797  * controller in a state capable of servicing IO.
1798  */
1799 void nvme_kill_queues(struct nvme_ctrl *ctrl)
1800 {
1801         struct nvme_ns *ns;
1802
1803         mutex_lock(&ctrl->namespaces_mutex);
1804         list_for_each_entry(ns, &ctrl->namespaces, list) {
1805                 /*
1806                  * Revalidating a dead namespace sets capacity to 0. This will
1807                  * end buffered writers dirtying pages that can't be synced.
1808                  */
1809                 if (!test_and_set_bit(NVME_NS_DEAD, &ns->flags))
1810                         revalidate_disk(ns->disk);
1811
1812                 blk_set_queue_dying(ns->queue);
1813                 blk_mq_abort_requeue_list(ns->queue);
1814                 blk_mq_start_stopped_hw_queues(ns->queue, true);
1815         }
1816         mutex_unlock(&ctrl->namespaces_mutex);
1817 }
1818 EXPORT_SYMBOL_GPL(nvme_kill_queues);
1819
1820 void nvme_stop_queues(struct nvme_ctrl *ctrl)
1821 {
1822         struct nvme_ns *ns;
1823
1824         mutex_lock(&ctrl->namespaces_mutex);
1825         list_for_each_entry(ns, &ctrl->namespaces, list) {
1826                 spin_lock_irq(ns->queue->queue_lock);
1827                 queue_flag_set(QUEUE_FLAG_STOPPED, ns->queue);
1828                 spin_unlock_irq(ns->queue->queue_lock);
1829
1830                 blk_mq_cancel_requeue_work(ns->queue);
1831                 blk_mq_stop_hw_queues(ns->queue);
1832         }
1833         mutex_unlock(&ctrl->namespaces_mutex);
1834 }
1835 EXPORT_SYMBOL_GPL(nvme_stop_queues);
1836
1837 void nvme_start_queues(struct nvme_ctrl *ctrl)
1838 {
1839         struct nvme_ns *ns;
1840
1841         mutex_lock(&ctrl->namespaces_mutex);
1842         list_for_each_entry(ns, &ctrl->namespaces, list) {
1843                 queue_flag_clear_unlocked(QUEUE_FLAG_STOPPED, ns->queue);
1844                 blk_mq_start_stopped_hw_queues(ns->queue, true);
1845                 blk_mq_kick_requeue_list(ns->queue);
1846         }
1847         mutex_unlock(&ctrl->namespaces_mutex);
1848 }
1849 EXPORT_SYMBOL_GPL(nvme_start_queues);
1850
1851 int __init nvme_core_init(void)
1852 {
1853         int result;
1854
1855         result = register_blkdev(nvme_major, "nvme");
1856         if (result < 0)
1857                 return result;
1858         else if (result > 0)
1859                 nvme_major = result;
1860
1861         result = __register_chrdev(nvme_char_major, 0, NVME_MINORS, "nvme",
1862                                                         &nvme_dev_fops);
1863         if (result < 0)
1864                 goto unregister_blkdev;
1865         else if (result > 0)
1866                 nvme_char_major = result;
1867
1868         nvme_class = class_create(THIS_MODULE, "nvme");
1869         if (IS_ERR(nvme_class)) {
1870                 result = PTR_ERR(nvme_class);
1871                 goto unregister_chrdev;
1872         }
1873
1874         return 0;
1875
1876  unregister_chrdev:
1877         __unregister_chrdev(nvme_char_major, 0, NVME_MINORS, "nvme");
1878  unregister_blkdev:
1879         unregister_blkdev(nvme_major, "nvme");
1880         return result;
1881 }
1882
1883 void nvme_core_exit(void)
1884 {
1885         class_destroy(nvme_class);
1886         __unregister_chrdev(nvme_char_major, 0, NVME_MINORS, "nvme");
1887         unregister_blkdev(nvme_major, "nvme");
1888 }
1889
1890 MODULE_LICENSE("GPL");
1891 MODULE_VERSION("1.0");
1892 module_init(nvme_core_init);
1893 module_exit(nvme_core_exit);