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 <linux/pm_qos.h>
  30 #include <scsi/sg.h>
  31 #include <asm/unaligned.h>
  32
  33 #include "nvme.h"
  34 #include "fabrics.h"
  35
  36 #define NVME_MINORS             (1U << MINORBITS)
  37
  38 unsigned char admin_timeout = 60;
  39 module_param(admin_timeout, byte, 0644);
  40 MODULE_PARM_DESC(admin_timeout, "timeout in seconds for admin commands");
  41 EXPORT_SYMBOL_GPL(admin_timeout);
  42
  43 unsigned char nvme_io_timeout = 30;
  44 module_param_named(io_timeout, nvme_io_timeout, byte, 0644);
  45 MODULE_PARM_DESC(io_timeout, "timeout in seconds for I/O");
  46 EXPORT_SYMBOL_GPL(nvme_io_timeout);
  47
  48 unsigned char shutdown_timeout = 5;
  49 module_param(shutdown_timeout, byte, 0644);
  50 MODULE_PARM_DESC(shutdown_timeout, "timeout in seconds for controller shutdown");
  51
  52 unsigned int nvme_max_retries = 5;
  53 module_param_named(max_retries, nvme_max_retries, uint, 0644);
  54 MODULE_PARM_DESC(max_retries, "max number of retries a command may have");
  55 EXPORT_SYMBOL_GPL(nvme_max_retries);
  56
  57 static int nvme_char_major;
  58 module_param(nvme_char_major, int, 0);
  59
  60 static unsigned long default_ps_max_latency_us = 25000;
  61 module_param(default_ps_max_latency_us, ulong, 0644);
  62 MODULE_PARM_DESC(default_ps_max_latency_us,
  63                  "max power saving latency for new devices; use PM QOS to change per device");
  64
  65 static LIST_HEAD(nvme_ctrl_list);
  66 static DEFINE_SPINLOCK(dev_list_lock);
  67
  68 static struct class *nvme_class;
  69
  70 void nvme_cancel_request(struct request *req, void *data, bool reserved)
  71 {
  72         int status;
  73
  74         if (!blk_mq_request_started(req))
  75                 return;
  76
  77         dev_dbg_ratelimited(((struct nvme_ctrl *) data)->device,
  78                                 "Cancelling I/O %d", req->tag);
  79
  80         status = NVME_SC_ABORT_REQ;
  81         if (blk_queue_dying(req->q))
  82                 status |= NVME_SC_DNR;
  83         blk_mq_complete_request(req, status);
  84 }
  85 EXPORT_SYMBOL_GPL(nvme_cancel_request);
  86
  87 bool nvme_change_ctrl_state(struct nvme_ctrl *ctrl,
  88                 enum nvme_ctrl_state new_state)
  89 {
  90         enum nvme_ctrl_state old_state;
  91         bool changed = false;
  92
  93         spin_lock_irq(&ctrl->lock);
  94
  95         old_state = ctrl->state;
  96         switch (new_state) {
  97         case NVME_CTRL_LIVE:
  98                 switch (old_state) {
  99                 case NVME_CTRL_NEW:
 100                 case NVME_CTRL_RESETTING:
 101                 case NVME_CTRL_RECONNECTING:
 102                         changed = true;
 103                         /* FALLTHRU */
 104                 default:
 105                         break;
 106                 }
 107                 break;
 108         case NVME_CTRL_RESETTING:
 109                 switch (old_state) {
 110                 case NVME_CTRL_NEW:
 111                 case NVME_CTRL_LIVE:
 112                 case NVME_CTRL_RECONNECTING:
 113                         changed = true;
 114                         /* FALLTHRU */
 115                 default:
 116                         break;
 117                 }
 118                 break;
 119         case NVME_CTRL_RECONNECTING:
 120                 switch (old_state) {
 121                 case NVME_CTRL_LIVE:
 122                         changed = true;
 123                         /* FALLTHRU */
 124                 default:
 125                         break;
 126                 }
 127                 break;
 128         case NVME_CTRL_DELETING:
 129                 switch (old_state) {
 130                 case NVME_CTRL_LIVE:
 131                 case NVME_CTRL_RESETTING:
 132                 case NVME_CTRL_RECONNECTING:
 133                         changed = true;
 134                         /* FALLTHRU */
 135                 default:
 136                         break;
 137                 }
 138                 break;
 139         case NVME_CTRL_DEAD:
 140                 switch (old_state) {
 141                 case NVME_CTRL_DELETING:
 142                         changed = true;
 143                         /* FALLTHRU */
 144                 default:
 145                         break;
 146                 }
 147                 break;
 148         default:
 149                 break;
 150         }
 151
 152         if (changed)
 153                 ctrl->state = new_state;
 154
 155         spin_unlock_irq(&ctrl->lock);
 156
 157         return changed;
 158 }
 159 EXPORT_SYMBOL_GPL(nvme_change_ctrl_state);
 160
 161 static void nvme_free_ns(struct kref *kref)
 162 {
 163         struct nvme_ns *ns = container_of(kref, struct nvme_ns, kref);
 164
 165         if (ns->ndev)
 166                 nvme_nvm_unregister(ns);
 167
 168         if (ns->disk) {
 169                 spin_lock(&dev_list_lock);
 170                 ns->disk->private_data = NULL;
 171                 spin_unlock(&dev_list_lock);
 172         }
 173
 174         put_disk(ns->disk);
 175         ida_simple_remove(&ns->ctrl->ns_ida, ns->instance);
 176         nvme_put_ctrl(ns->ctrl);
 177         kfree(ns);
 178 }
 179
 180 static void nvme_put_ns(struct nvme_ns *ns)
 181 {
 182         kref_put(&ns->kref, nvme_free_ns);
 183 }
 184
 185 static struct nvme_ns *nvme_get_ns_from_disk(struct gendisk *disk)
 186 {
 187         struct nvme_ns *ns;
 188
 189         spin_lock(&dev_list_lock);
 190         ns = disk->private_data;
 191         if (ns) {
 192                 if (!kref_get_unless_zero(&ns->kref))
 193                         goto fail;
 194                 if (!try_module_get(ns->ctrl->ops->module))
 195                         goto fail_put_ns;
 196         }
 197         spin_unlock(&dev_list_lock);
 198
 199         return ns;
 200
 201 fail_put_ns:
 202         kref_put(&ns->kref, nvme_free_ns);
 203 fail:
 204         spin_unlock(&dev_list_lock);
 205         return NULL;
 206 }
 207
 208 void nvme_requeue_req(struct request *req)
 209 {
 210         blk_mq_requeue_request(req, !blk_mq_queue_stopped(req->q));
 211 }
 212 EXPORT_SYMBOL_GPL(nvme_requeue_req);
 213
 214 struct request *nvme_alloc_request(struct request_queue *q,
 215                 struct nvme_command *cmd, unsigned int flags, int qid)
 216 {
 217         unsigned op = nvme_is_write(cmd) ? REQ_OP_DRV_OUT : REQ_OP_DRV_IN;
 218         struct request *req;
 219
 220         if (qid == NVME_QID_ANY) {
 221                 req = blk_mq_alloc_request(q, op, flags);
 222         } else {
 223                 req = blk_mq_alloc_request_hctx(q, op, flags,
 224                                 qid ? qid - 1 : 0);
 225         }
 226         if (IS_ERR(req))
 227                 return req;
 228
 229         req->cmd_flags |= REQ_FAILFAST_DRIVER;
 230         nvme_req(req)->cmd = cmd;
 231
 232         return req;
 233 }
 234 EXPORT_SYMBOL_GPL(nvme_alloc_request);
 235
 236 static inline void nvme_setup_flush(struct nvme_ns *ns,
 237                 struct nvme_command *cmnd)
 238 {
 239         memset(cmnd, 0, sizeof(*cmnd));
 240         cmnd->common.opcode = nvme_cmd_flush;
 241         cmnd->common.nsid = cpu_to_le32(ns->ns_id);
 242 }
 243
 244 static inline int nvme_setup_discard(struct nvme_ns *ns, struct request *req,
 245                 struct nvme_command *cmnd)
 246 {
 247         unsigned short segments = blk_rq_nr_discard_segments(req), n = 0;
 248         struct nvme_dsm_range *range;
 249         struct bio *bio;
 250
 251         range = kmalloc_array(segments, sizeof(*range), GFP_ATOMIC);
 252         if (!range)
 253                 return BLK_MQ_RQ_QUEUE_BUSY;
 254
 255         __rq_for_each_bio(bio, req) {
 256                 u64 slba = nvme_block_nr(ns, bio->bi_iter.bi_sector);
 257                 u32 nlb = bio->bi_iter.bi_size >> ns->lba_shift;
 258
 259                 range[n].cattr = cpu_to_le32(0);
 260                 range[n].nlb = cpu_to_le32(nlb);
 261                 range[n].slba = cpu_to_le64(slba);
 262                 n++;
 263         }
 264
 265         if (WARN_ON_ONCE(n != segments)) {
 266                 kfree(range);
 267                 return BLK_MQ_RQ_QUEUE_ERROR;
 268         }
 269
 270         memset(cmnd, 0, sizeof(*cmnd));
 271         cmnd->dsm.opcode = nvme_cmd_dsm;
 272         cmnd->dsm.nsid = cpu_to_le32(ns->ns_id);
 273         cmnd->dsm.nr = cpu_to_le32(segments - 1);
 274         cmnd->dsm.attributes = cpu_to_le32(NVME_DSMGMT_AD);
 275
 276         req->special_vec.bv_page = virt_to_page(range);
 277         req->special_vec.bv_offset = offset_in_page(range);
 278         req->special_vec.bv_len = sizeof(*range) * segments;
 279         req->rq_flags |= RQF_SPECIAL_PAYLOAD;
 280
 281         return BLK_MQ_RQ_QUEUE_OK;
 282 }
 283
 284 static inline void nvme_setup_rw(struct nvme_ns *ns, struct request *req,
 285                 struct nvme_command *cmnd)
 286 {
 287         u16 control = 0;
 288         u32 dsmgmt = 0;
 289
 290         if (req->cmd_flags & REQ_FUA)
 291                 control |= NVME_RW_FUA;
 292         if (req->cmd_flags & (REQ_FAILFAST_DEV | REQ_RAHEAD))
 293                 control |= NVME_RW_LR;
 294
 295         if (req->cmd_flags & REQ_RAHEAD)
 296                 dsmgmt |= NVME_RW_DSM_FREQ_PREFETCH;
 297
 298         memset(cmnd, 0, sizeof(*cmnd));
 299         cmnd->rw.opcode = (rq_data_dir(req) ? nvme_cmd_write : nvme_cmd_read);
 300         cmnd->rw.nsid = cpu_to_le32(ns->ns_id);
 301         cmnd->rw.slba = cpu_to_le64(nvme_block_nr(ns, blk_rq_pos(req)));
 302         cmnd->rw.length = cpu_to_le16((blk_rq_bytes(req) >> ns->lba_shift) - 1);
 303
 304         if (ns->ms) {
 305                 switch (ns->pi_type) {
 306                 case NVME_NS_DPS_PI_TYPE3:
 307                         control |= NVME_RW_PRINFO_PRCHK_GUARD;
 308                         break;
 309                 case NVME_NS_DPS_PI_TYPE1:
 310                 case NVME_NS_DPS_PI_TYPE2:
 311                         control |= NVME_RW_PRINFO_PRCHK_GUARD |
 312                                         NVME_RW_PRINFO_PRCHK_REF;
 313                         cmnd->rw.reftag = cpu_to_le32(
 314                                         nvme_block_nr(ns, blk_rq_pos(req)));
 315                         break;
 316                 }
 317                 if (!blk_integrity_rq(req))
 318                         control |= NVME_RW_PRINFO_PRACT;
 319         }
 320
 321         cmnd->rw.control = cpu_to_le16(control);
 322         cmnd->rw.dsmgmt = cpu_to_le32(dsmgmt);
 323 }
 324
 325 int nvme_setup_cmd(struct nvme_ns *ns, struct request *req,
 326                 struct nvme_command *cmd)
 327 {
 328         int ret = BLK_MQ_RQ_QUEUE_OK;
 329
 330         switch (req_op(req)) {
 331         case REQ_OP_DRV_IN:
 332         case REQ_OP_DRV_OUT:
 333                 memcpy(cmd, nvme_req(req)->cmd, sizeof(*cmd));
 334                 break;
 335         case REQ_OP_FLUSH:
 336                 nvme_setup_flush(ns, cmd);
 337                 break;
 338         case REQ_OP_DISCARD:
 339                 ret = nvme_setup_discard(ns, req, cmd);
 340                 break;
 341         case REQ_OP_READ:
 342         case REQ_OP_WRITE:
 343                 nvme_setup_rw(ns, req, cmd);
 344                 break;
 345         default:
 346                 WARN_ON_ONCE(1);
 347                 return BLK_MQ_RQ_QUEUE_ERROR;
 348         }
 349
 350         cmd->common.command_id = req->tag;
 351         return ret;
 352 }
 353 EXPORT_SYMBOL_GPL(nvme_setup_cmd);
 354
 355 /*
 356  * Returns 0 on success.  If the result is negative, it's a Linux error code;
 357  * if the result is positive, it's an NVM Express status code
 358  */
 359 int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
 360                 union nvme_result *result, void *buffer, unsigned bufflen,
 361                 unsigned timeout, int qid, int at_head, int flags)
 362 {
 363         struct request *req;
 364         int ret;
 365
 366         req = nvme_alloc_request(q, cmd, flags, qid);
 367         if (IS_ERR(req))
 368                 return PTR_ERR(req);
 369
 370         req->timeout = timeout ? timeout : ADMIN_TIMEOUT;
 371
 372         if (buffer && bufflen) {
 373                 ret = blk_rq_map_kern(q, req, buffer, bufflen, GFP_KERNEL);
 374                 if (ret)
 375                         goto out;
 376         }
 377
 378         blk_execute_rq(req->q, NULL, req, at_head);
 379         if (result)
 380                 *result = nvme_req(req)->result;
 381         ret = req->errors;
 382  out:
 383         blk_mq_free_request(req);
 384         return ret;
 385 }
 386 EXPORT_SYMBOL_GPL(__nvme_submit_sync_cmd);
 387
 388 int nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
 389                 void *buffer, unsigned bufflen)
 390 {
 391         return __nvme_submit_sync_cmd(q, cmd, NULL, buffer, bufflen, 0,
 392                         NVME_QID_ANY, 0, 0);
 393 }
 394 EXPORT_SYMBOL_GPL(nvme_submit_sync_cmd);
 395
 396 int __nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
 397                 void __user *ubuffer, unsigned bufflen,
 398                 void __user *meta_buffer, unsigned meta_len, u32 meta_seed,
 399                 u32 *result, unsigned timeout)
 400 {
 401         bool write = nvme_is_write(cmd);
 402         struct nvme_ns *ns = q->queuedata;
 403         struct gendisk *disk = ns ? ns->disk : NULL;
 404         struct request *req;
 405         struct bio *bio = NULL;
 406         void *meta = NULL;
 407         int ret;
 408
 409         req = nvme_alloc_request(q, cmd, 0, NVME_QID_ANY);
 410         if (IS_ERR(req))
 411                 return PTR_ERR(req);
 412
 413         req->timeout = timeout ? timeout : ADMIN_TIMEOUT;
 414
 415         if (ubuffer && bufflen) {
 416                 ret = blk_rq_map_user(q, req, NULL, ubuffer, bufflen,
 417                                 GFP_KERNEL);
 418                 if (ret)
 419                         goto out;
 420                 bio = req->bio;
 421
 422                 if (!disk)
 423                         goto submit;
 424                 bio->bi_bdev = bdget_disk(disk, 0);
 425                 if (!bio->bi_bdev) {
 426                         ret = -ENODEV;
 427                         goto out_unmap;
 428                 }
 429
 430                 if (meta_buffer && meta_len) {
 431                         struct bio_integrity_payload *bip;
 432
 433                         meta = kmalloc(meta_len, GFP_KERNEL);
 434                         if (!meta) {
 435                                 ret = -ENOMEM;
 436                                 goto out_unmap;
 437                         }
 438
 439                         if (write) {
 440                                 if (copy_from_user(meta, meta_buffer,
 441                                                 meta_len)) {
 442                                         ret = -EFAULT;
 443                                         goto out_free_meta;
 444                                 }
 445                         }
 446
 447                         bip = bio_integrity_alloc(bio, GFP_KERNEL, 1);
 448                         if (IS_ERR(bip)) {
 449                                 ret = PTR_ERR(bip);
 450                                 goto out_free_meta;
 451                         }
 452
 453                         bip->bip_iter.bi_size = meta_len;
 454                         bip->bip_iter.bi_sector = meta_seed;
 455
 456                         ret = bio_integrity_add_page(bio, virt_to_page(meta),
 457                                         meta_len, offset_in_page(meta));
 458                         if (ret != meta_len) {
 459                                 ret = -ENOMEM;
 460                                 goto out_free_meta;
 461                         }
 462                 }
 463         }
 464  submit:
 465         blk_execute_rq(req->q, disk, req, 0);
 466         ret = req->errors;
 467         if (result)
 468                 *result = le32_to_cpu(nvme_req(req)->result.u32);
 469         if (meta && !ret && !write) {
 470                 if (copy_to_user(meta_buffer, meta, meta_len))
 471                         ret = -EFAULT;
 472         }
 473  out_free_meta:
 474         kfree(meta);
 475  out_unmap:
 476         if (bio) {
 477                 if (disk && bio->bi_bdev)
 478                         bdput(bio->bi_bdev);
 479                 blk_rq_unmap_user(bio);
 480         }
 481  out:
 482         blk_mq_free_request(req);
 483         return ret;
 484 }
 485
 486 int nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
 487                 void __user *ubuffer, unsigned bufflen, u32 *result,
 488                 unsigned timeout)
 489 {
 490         return __nvme_submit_user_cmd(q, cmd, ubuffer, bufflen, NULL, 0, 0,
 491                         result, timeout);
 492 }
 493
 494 static void nvme_keep_alive_end_io(struct request *rq, int error)
 495 {
 496         struct nvme_ctrl *ctrl = rq->end_io_data;
 497
 498         blk_mq_free_request(rq);
 499
 500         if (error) {
 501                 dev_err(ctrl->device,
 502                         "failed nvme_keep_alive_end_io error=%d\n", error);
 503                 return;
 504         }
 505
 506         schedule_delayed_work(&ctrl->ka_work, ctrl->kato * HZ);
 507 }
 508
 509 static int nvme_keep_alive(struct nvme_ctrl *ctrl)
 510 {
 511         struct nvme_command c;
 512         struct request *rq;
 513
 514         memset(&c, 0, sizeof(c));
 515         c.common.opcode = nvme_admin_keep_alive;
 516
 517         rq = nvme_alloc_request(ctrl->admin_q, &c, BLK_MQ_REQ_RESERVED,
 518                         NVME_QID_ANY);
 519         if (IS_ERR(rq))
 520                 return PTR_ERR(rq);
 521
 522         rq->timeout = ctrl->kato * HZ;
 523         rq->end_io_data = ctrl;
 524
 525         blk_execute_rq_nowait(rq->q, NULL, rq, 0, nvme_keep_alive_end_io);
 526
 527         return 0;
 528 }
 529
 530 static void nvme_keep_alive_work(struct work_struct *work)
 531 {
 532         struct nvme_ctrl *ctrl = container_of(to_delayed_work(work),
 533                         struct nvme_ctrl, ka_work);
 534
 535         if (nvme_keep_alive(ctrl)) {
 536                 /* allocation failure, reset the controller */
 537                 dev_err(ctrl->device, "keep-alive failed\n");
 538                 ctrl->ops->reset_ctrl(ctrl);
 539                 return;
 540         }
 541 }
 542
 543 void nvme_start_keep_alive(struct nvme_ctrl *ctrl)
 544 {
 545         if (unlikely(ctrl->kato == 0))
 546                 return;
 547
 548         INIT_DELAYED_WORK(&ctrl->ka_work, nvme_keep_alive_work);
 549         schedule_delayed_work(&ctrl->ka_work, ctrl->kato * HZ);
 550 }
 551 EXPORT_SYMBOL_GPL(nvme_start_keep_alive);
 552
 553 void nvme_stop_keep_alive(struct nvme_ctrl *ctrl)
 554 {
 555         if (unlikely(ctrl->kato == 0))
 556                 return;
 557
 558         cancel_delayed_work_sync(&ctrl->ka_work);
 559 }
 560 EXPORT_SYMBOL_GPL(nvme_stop_keep_alive);
 561
 562 int nvme_identify_ctrl(struct nvme_ctrl *dev, struct nvme_id_ctrl **id)
 563 {
 564         struct nvme_command c = { };
 565         int error;
 566
 567         /* gcc-4.4.4 (at least) has issues with initializers and anon unions */
 568         c.identify.opcode = nvme_admin_identify;
 569         c.identify.cns = NVME_ID_CNS_CTRL;
 570
 571         *id = kmalloc(sizeof(struct nvme_id_ctrl), GFP_KERNEL);
 572         if (!*id)
 573                 return -ENOMEM;
 574
 575         error = nvme_submit_sync_cmd(dev->admin_q, &c, *id,
 576                         sizeof(struct nvme_id_ctrl));
 577         if (error)
 578                 kfree(*id);
 579         return error;
 580 }
 581
 582 static int nvme_identify_ns_list(struct nvme_ctrl *dev, unsigned nsid, __le32 *ns_list)
 583 {
 584         struct nvme_command c = { };
 585
 586         c.identify.opcode = nvme_admin_identify;
 587         c.identify.cns = NVME_ID_CNS_NS_ACTIVE_LIST;
 588         c.identify.nsid = cpu_to_le32(nsid);
 589         return nvme_submit_sync_cmd(dev->admin_q, &c, ns_list, 0x1000);
 590 }
 591
 592 int nvme_identify_ns(struct nvme_ctrl *dev, unsigned nsid,
 593                 struct nvme_id_ns **id)
 594 {
 595         struct nvme_command c = { };
 596         int error;
 597
 598         /* gcc-4.4.4 (at least) has issues with initializers and anon unions */
 599         c.identify.opcode = nvme_admin_identify;
 600         c.identify.nsid = cpu_to_le32(nsid);
 601         c.identify.cns = NVME_ID_CNS_NS;
 602
 603         *id = kmalloc(sizeof(struct nvme_id_ns), GFP_KERNEL);
 604         if (!*id)
 605                 return -ENOMEM;
 606
 607         error = nvme_submit_sync_cmd(dev->admin_q, &c, *id,
 608                         sizeof(struct nvme_id_ns));
 609         if (error)
 610                 kfree(*id);
 611         return error;
 612 }
 613
 614 int nvme_get_features(struct nvme_ctrl *dev, unsigned fid, unsigned nsid,
 615                       void *buffer, size_t buflen, u32 *result)
 616 {
 617         struct nvme_command c;
 618         union nvme_result res;
 619         int ret;
 620
 621         memset(&c, 0, sizeof(c));
 622         c.features.opcode = nvme_admin_get_features;
 623         c.features.nsid = cpu_to_le32(nsid);
 624         c.features.fid = cpu_to_le32(fid);
 625
 626         ret = __nvme_submit_sync_cmd(dev->admin_q, &c, &res, buffer, buflen, 0,
 627                         NVME_QID_ANY, 0, 0);
 628         if (ret >= 0 && result)
 629                 *result = le32_to_cpu(res.u32);
 630         return ret;
 631 }
 632
 633 int nvme_set_features(struct nvme_ctrl *dev, unsigned fid, unsigned dword11,
 634                       void *buffer, size_t buflen, u32 *result)
 635 {
 636         struct nvme_command c;
 637         union nvme_result res;
 638         int ret;
 639
 640         memset(&c, 0, sizeof(c));
 641         c.features.opcode = nvme_admin_set_features;
 642         c.features.fid = cpu_to_le32(fid);
 643         c.features.dword11 = cpu_to_le32(dword11);
 644
 645         ret = __nvme_submit_sync_cmd(dev->admin_q, &c, &res,
 646                         buffer, buflen, 0, NVME_QID_ANY, 0, 0);
 647         if (ret >= 0 && result)
 648                 *result = le32_to_cpu(res.u32);
 649         return ret;
 650 }
 651
 652 int nvme_get_log_page(struct nvme_ctrl *dev, struct nvme_smart_log **log)
 653 {
 654         struct nvme_command c = { };
 655         int error;
 656
 657         c.common.opcode = nvme_admin_get_log_page,
 658         c.common.nsid = cpu_to_le32(0xFFFFFFFF),
 659         c.common.cdw10[0] = cpu_to_le32(
 660                         (((sizeof(struct nvme_smart_log) / 4) - 1) << 16) |
 661                          NVME_LOG_SMART),
 662
 663         *log = kmalloc(sizeof(struct nvme_smart_log), GFP_KERNEL);
 664         if (!*log)
 665                 return -ENOMEM;
 666
 667         error = nvme_submit_sync_cmd(dev->admin_q, &c, *log,
 668                         sizeof(struct nvme_smart_log));
 669         if (error)
 670                 kfree(*log);
 671         return error;
 672 }
 673
 674 int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count)
 675 {
 676         u32 q_count = (*count - 1) | ((*count - 1) << 16);
 677         u32 result;
 678         int status, nr_io_queues;
 679
 680         status = nvme_set_features(ctrl, NVME_FEAT_NUM_QUEUES, q_count, NULL, 0,
 681                         &result);
 682         if (status < 0)
 683                 return status;
 684
 685         /*
 686          * Degraded controllers might return an error when setting the queue
 687          * count.  We still want to be able to bring them online and offer
 688          * access to the admin queue, as that might be only way to fix them up.
 689          */
 690         if (status > 0) {
 691                 dev_err(ctrl->dev, "Could not set queue count (%d)\n", status);
 692                 *count = 0;
 693         } else {
 694                 nr_io_queues = min(result & 0xffff, result >> 16) + 1;
 695                 *count = min(*count, nr_io_queues);
 696         }
 697
 698         return 0;
 699 }
 700 EXPORT_SYMBOL_GPL(nvme_set_queue_count);
 701
 702 static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio)
 703 {
 704         struct nvme_user_io io;
 705         struct nvme_command c;
 706         unsigned length, meta_len;
 707         void __user *metadata;
 708
 709         if (copy_from_user(&io, uio, sizeof(io)))
 710                 return -EFAULT;
 711         if (io.flags)
 712                 return -EINVAL;
 713
 714         switch (io.opcode) {
 715         case nvme_cmd_write:
 716         case nvme_cmd_read:
 717         case nvme_cmd_compare:
 718                 break;
 719         default:
 720                 return -EINVAL;
 721         }
 722
 723         length = (io.nblocks + 1) << ns->lba_shift;
 724         meta_len = (io.nblocks + 1) * ns->ms;
 725         metadata = (void __user *)(uintptr_t)io.metadata;
 726
 727         if (ns->ext) {
 728                 length += meta_len;
 729                 meta_len = 0;
 730         } else if (meta_len) {
 731                 if ((io.metadata & 3) || !io.metadata)
 732                         return -EINVAL;
 733         }
 734
 735         memset(&c, 0, sizeof(c));
 736         c.rw.opcode = io.opcode;
 737         c.rw.flags = io.flags;
 738         c.rw.nsid = cpu_to_le32(ns->ns_id);
 739         c.rw.slba = cpu_to_le64(io.slba);
 740         c.rw.length = cpu_to_le16(io.nblocks);
 741         c.rw.control = cpu_to_le16(io.control);
 742         c.rw.dsmgmt = cpu_to_le32(io.dsmgmt);
 743         c.rw.reftag = cpu_to_le32(io.reftag);
 744         c.rw.apptag = cpu_to_le16(io.apptag);
 745         c.rw.appmask = cpu_to_le16(io.appmask);
 746
 747         return __nvme_submit_user_cmd(ns->queue, &c,
 748                         (void __user *)(uintptr_t)io.addr, length,
 749                         metadata, meta_len, io.slba, NULL, 0);
 750 }
 751
 752 static int nvme_user_cmd(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
 753                         struct nvme_passthru_cmd __user *ucmd)
 754 {
 755         struct nvme_passthru_cmd cmd;
 756         struct nvme_command c;
 757         unsigned timeout = 0;
 758         int status;
 759
 760         if (!capable(CAP_SYS_ADMIN))
 761                 return -EACCES;
 762         if (copy_from_user(&cmd, ucmd, sizeof(cmd)))
 763                 return -EFAULT;
 764         if (cmd.flags)
 765                 return -EINVAL;
 766
 767         memset(&c, 0, sizeof(c));
 768         c.common.opcode = cmd.opcode;
 769         c.common.flags = cmd.flags;
 770         c.common.nsid = cpu_to_le32(cmd.nsid);
 771         c.common.cdw2[0] = cpu_to_le32(cmd.cdw2);
 772         c.common.cdw2[1] = cpu_to_le32(cmd.cdw3);
 773         c.common.cdw10[0] = cpu_to_le32(cmd.cdw10);
 774         c.common.cdw10[1] = cpu_to_le32(cmd.cdw11);
 775         c.common.cdw10[2] = cpu_to_le32(cmd.cdw12);
 776         c.common.cdw10[3] = cpu_to_le32(cmd.cdw13);
 777         c.common.cdw10[4] = cpu_to_le32(cmd.cdw14);
 778         c.common.cdw10[5] = cpu_to_le32(cmd.cdw15);
 779
 780         if (cmd.timeout_ms)
 781                 timeout = msecs_to_jiffies(cmd.timeout_ms);
 782
 783         status = nvme_submit_user_cmd(ns ? ns->queue : ctrl->admin_q, &c,
 784                         (void __user *)(uintptr_t)cmd.addr, cmd.data_len,
 785                         &cmd.result, timeout);
 786         if (status >= 0) {
 787                 if (put_user(cmd.result, &ucmd->result))
 788                         return -EFAULT;
 789         }
 790
 791         return status;
 792 }
 793
 794 static int nvme_ioctl(struct block_device *bdev, fmode_t mode,
 795                 unsigned int cmd, unsigned long arg)
 796 {
 797         struct nvme_ns *ns = bdev->bd_disk->private_data;
 798
 799         switch (cmd) {
 800         case NVME_IOCTL_ID:
 801                 force_successful_syscall_return();
 802                 return ns->ns_id;
 803         case NVME_IOCTL_ADMIN_CMD:
 804                 return nvme_user_cmd(ns->ctrl, NULL, (void __user *)arg);
 805         case NVME_IOCTL_IO_CMD:
 806                 return nvme_user_cmd(ns->ctrl, ns, (void __user *)arg);
 807         case NVME_IOCTL_SUBMIT_IO:
 808                 return nvme_submit_io(ns, (void __user *)arg);
 809 #ifdef CONFIG_BLK_DEV_NVME_SCSI
 810         case SG_GET_VERSION_NUM:
 811                 return nvme_sg_get_version_num((void __user *)arg);
 812         case SG_IO:
 813                 return nvme_sg_io(ns, (void __user *)arg);
 814 #endif
 815         default:
 816 #ifdef CONFIG_NVM
 817                 if (ns->ndev)
 818                         return nvme_nvm_ioctl(ns, cmd, arg);
 819 #endif
 820                 if (is_sed_ioctl(cmd))
 821                         return sed_ioctl(ns->ctrl->opal_dev, cmd,
 822                                          (void __user *) arg);
 823                 return -ENOTTY;
 824         }
 825 }
 826
 827 #ifdef CONFIG_COMPAT
 828 static int nvme_compat_ioctl(struct block_device *bdev, fmode_t mode,
 829                         unsigned int cmd, unsigned long arg)
 830 {
 831         switch (cmd) {
 832         case SG_IO:
 833                 return -ENOIOCTLCMD;
 834         }
 835         return nvme_ioctl(bdev, mode, cmd, arg);
 836 }
 837 #else
 838 #define nvme_compat_ioctl       NULL
 839 #endif
 840
 841 static int nvme_open(struct block_device *bdev, fmode_t mode)
 842 {
 843         return nvme_get_ns_from_disk(bdev->bd_disk) ? 0 : -ENXIO;
 844 }
 845
 846 static void nvme_release(struct gendisk *disk, fmode_t mode)
 847 {
 848         struct nvme_ns *ns = disk->private_data;
 849
 850         module_put(ns->ctrl->ops->module);
 851         nvme_put_ns(ns);
 852 }
 853
 854 static int nvme_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 855 {
 856         /* some standard values */
 857         geo->heads = 1 << 6;
 858         geo->sectors = 1 << 5;
 859         geo->cylinders = get_capacity(bdev->bd_disk) >> 11;
 860         return 0;
 861 }
 862
 863 #ifdef CONFIG_BLK_DEV_INTEGRITY
 864 static void nvme_init_integrity(struct nvme_ns *ns)
 865 {
 866         struct blk_integrity integrity;
 867
 868         memset(&integrity, 0, sizeof(integrity));
 869         switch (ns->pi_type) {
 870         case NVME_NS_DPS_PI_TYPE3:
 871                 integrity.profile = &t10_pi_type3_crc;
 872                 integrity.tag_size = sizeof(u16) + sizeof(u32);
 873                 integrity.flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
 874                 break;
 875         case NVME_NS_DPS_PI_TYPE1:
 876         case NVME_NS_DPS_PI_TYPE2:
 877                 integrity.profile = &t10_pi_type1_crc;
 878                 integrity.tag_size = sizeof(u16);
 879                 integrity.flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
 880                 break;
 881         default:
 882                 integrity.profile = NULL;
 883                 break;
 884         }
 885         integrity.tuple_size = ns->ms;
 886         blk_integrity_register(ns->disk, &integrity);
 887         blk_queue_max_integrity_segments(ns->queue, 1);
 888 }
 889 #else
 890 static void nvme_init_integrity(struct nvme_ns *ns)
 891 {
 892 }
 893 #endif /* CONFIG_BLK_DEV_INTEGRITY */
 894
 895 static void nvme_config_discard(struct nvme_ns *ns)
 896 {
 897         struct nvme_ctrl *ctrl = ns->ctrl;
 898         u32 logical_block_size = queue_logical_block_size(ns->queue);
 899
 900         BUILD_BUG_ON(PAGE_SIZE / sizeof(struct nvme_dsm_range) <
 901                         NVME_DSM_MAX_RANGES);
 902
 903         if (ctrl->quirks & NVME_QUIRK_DISCARD_ZEROES)
 904                 ns->queue->limits.discard_zeroes_data = 1;
 905         else
 906                 ns->queue->limits.discard_zeroes_data = 0;
 907
 908         ns->queue->limits.discard_alignment = logical_block_size;
 909         ns->queue->limits.discard_granularity = logical_block_size;
 910         blk_queue_max_discard_sectors(ns->queue, UINT_MAX);
 911         blk_queue_max_discard_segments(ns->queue, NVME_DSM_MAX_RANGES);
 912         queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, ns->queue);
 913 }
 914
 915 static int nvme_revalidate_ns(struct nvme_ns *ns, struct nvme_id_ns **id)
 916 {
 917         if (nvme_identify_ns(ns->ctrl, ns->ns_id, id)) {
 918                 dev_warn(ns->ctrl->dev, "%s: Identify failure\n", __func__);
 919                 return -ENODEV;
 920         }
 921
 922         if ((*id)->ncap == 0) {
 923                 kfree(*id);
 924                 return -ENODEV;
 925         }
 926
 927         if (ns->ctrl->vs >= NVME_VS(1, 1, 0))
 928                 memcpy(ns->eui, (*id)->eui64, sizeof(ns->eui));
 929         if (ns->ctrl->vs >= NVME_VS(1, 2, 0))
 930                 memcpy(ns->uuid, (*id)->nguid, sizeof(ns->uuid));
 931
 932         return 0;
 933 }
 934
 935 static void __nvme_revalidate_disk(struct gendisk *disk, struct nvme_id_ns *id)
 936 {
 937         struct nvme_ns *ns = disk->private_data;
 938         u8 lbaf, pi_type;
 939         u16 old_ms;
 940         unsigned short bs;
 941
 942         old_ms = ns->ms;
 943         lbaf = id->flbas & NVME_NS_FLBAS_LBA_MASK;
 944         ns->lba_shift = id->lbaf[lbaf].ds;
 945         ns->ms = le16_to_cpu(id->lbaf[lbaf].ms);
 946         ns->ext = ns->ms && (id->flbas & NVME_NS_FLBAS_META_EXT);
 947
 948         /*
 949          * If identify namespace failed, use default 512 byte block size so
 950          * block layer can use before failing read/write for 0 capacity.
 951          */
 952         if (ns->lba_shift == 0)
 953                 ns->lba_shift = 9;
 954         bs = 1 << ns->lba_shift;
 955         /* XXX: PI implementation requires metadata equal t10 pi tuple size */
 956         pi_type = ns->ms == sizeof(struct t10_pi_tuple) ?
 957                                         id->dps & NVME_NS_DPS_PI_MASK : 0;
 958
 959         blk_mq_freeze_queue(disk->queue);
 960         if (blk_get_integrity(disk) && (ns->pi_type != pi_type ||
 961                                 ns->ms != old_ms ||
 962                                 bs != queue_logical_block_size(disk->queue) ||
 963                                 (ns->ms && ns->ext)))
 964                 blk_integrity_unregister(disk);
 965
 966         ns->pi_type = pi_type;
 967         blk_queue_logical_block_size(ns->queue, bs);
 968
 969         if (ns->ms && !blk_get_integrity(disk) && !ns->ext)
 970                 nvme_init_integrity(ns);
 971         if (ns->ms && !(ns->ms == 8 && ns->pi_type) && !blk_get_integrity(disk))
 972                 set_capacity(disk, 0);
 973         else
 974                 set_capacity(disk, le64_to_cpup(&id->nsze) << (ns->lba_shift - 9));
 975
 976         if (ns->ctrl->oncs & NVME_CTRL_ONCS_DSM)
 977                 nvme_config_discard(ns);
 978         blk_mq_unfreeze_queue(disk->queue);
 979 }
 980
 981 static int nvme_revalidate_disk(struct gendisk *disk)
 982 {
 983         struct nvme_ns *ns = disk->private_data;
 984         struct nvme_id_ns *id = NULL;
 985         int ret;
 986
 987         if (test_bit(NVME_NS_DEAD, &ns->flags)) {
 988                 set_capacity(disk, 0);
 989                 return -ENODEV;
 990         }
 991
 992         ret = nvme_revalidate_ns(ns, &id);
 993         if (ret)
 994                 return ret;
 995
 996         __nvme_revalidate_disk(disk, id);
 997         kfree(id);
 998
 999         return 0;
1000 }
1001
1002 static char nvme_pr_type(enum pr_type type)
1003 {
1004         switch (type) {
1005         case PR_WRITE_EXCLUSIVE:
1006                 return 1;
1007         case PR_EXCLUSIVE_ACCESS:
1008                 return 2;
1009         case PR_WRITE_EXCLUSIVE_REG_ONLY:
1010                 return 3;
1011         case PR_EXCLUSIVE_ACCESS_REG_ONLY:
1012                 return 4;
1013         case PR_WRITE_EXCLUSIVE_ALL_REGS:
1014                 return 5;
1015         case PR_EXCLUSIVE_ACCESS_ALL_REGS:
1016                 return 6;
1017         default:
1018                 return 0;
1019         }
1020 };
1021
1022 static int nvme_pr_command(struct block_device *bdev, u32 cdw10,
1023                                 u64 key, u64 sa_key, u8 op)
1024 {
1025         struct nvme_ns *ns = bdev->bd_disk->private_data;
1026         struct nvme_command c;
1027         u8 data[16] = { 0, };
1028
1029         put_unaligned_le64(key, &data[0]);
1030         put_unaligned_le64(sa_key, &data[8]);
1031
1032         memset(&c, 0, sizeof(c));
1033         c.common.opcode = op;
1034         c.common.nsid = cpu_to_le32(ns->ns_id);
1035         c.common.cdw10[0] = cpu_to_le32(cdw10);
1036
1037         return nvme_submit_sync_cmd(ns->queue, &c, data, 16);
1038 }
1039
1040 static int nvme_pr_register(struct block_device *bdev, u64 old,
1041                 u64 new, unsigned flags)
1042 {
1043         u32 cdw10;
1044
1045         if (flags & ~PR_FL_IGNORE_KEY)
1046                 return -EOPNOTSUPP;
1047
1048         cdw10 = old ? 2 : 0;
1049         cdw10 |= (flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0;
1050         cdw10 |= (1 << 30) | (1 << 31); /* PTPL=1 */
1051         return nvme_pr_command(bdev, cdw10, old, new, nvme_cmd_resv_register);
1052 }
1053
1054 static int nvme_pr_reserve(struct block_device *bdev, u64 key,
1055                 enum pr_type type, unsigned flags)
1056 {
1057         u32 cdw10;
1058
1059         if (flags & ~PR_FL_IGNORE_KEY)
1060                 return -EOPNOTSUPP;
1061
1062         cdw10 = nvme_pr_type(type) << 8;
1063         cdw10 |= ((flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0);
1064         return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_acquire);
1065 }
1066
1067 static int nvme_pr_preempt(struct block_device *bdev, u64 old, u64 new,
1068                 enum pr_type type, bool abort)
1069 {
1070         u32 cdw10 = nvme_pr_type(type) << 8 | abort ? 2 : 1;
1071         return nvme_pr_command(bdev, cdw10, old, new, nvme_cmd_resv_acquire);
1072 }
1073
1074 static int nvme_pr_clear(struct block_device *bdev, u64 key)
1075 {
1076         u32 cdw10 = 1 | (key ? 1 << 3 : 0);
1077         return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_register);
1078 }
1079
1080 static int nvme_pr_release(struct block_device *bdev, u64 key, enum pr_type type)
1081 {
1082         u32 cdw10 = nvme_pr_type(type) << 8 | key ? 1 << 3 : 0;
1083         return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_release);
1084 }
1085
1086 static const struct pr_ops nvme_pr_ops = {
1087         .pr_register    = nvme_pr_register,
1088         .pr_reserve     = nvme_pr_reserve,
1089         .pr_release     = nvme_pr_release,
1090         .pr_preempt     = nvme_pr_preempt,
1091         .pr_clear       = nvme_pr_clear,
1092 };
1093
1094 #ifdef CONFIG_BLK_SED_OPAL
1095 int nvme_sec_submit(void *data, u16 spsp, u8 secp, void *buffer, size_t len,
1096                 bool send)
1097 {
1098         struct nvme_ctrl *ctrl = data;
1099         struct nvme_command cmd;
1100
1101         memset(&cmd, 0, sizeof(cmd));
1102         if (send)
1103                 cmd.common.opcode = nvme_admin_security_send;
1104         else
1105                 cmd.common.opcode = nvme_admin_security_recv;
1106         cmd.common.nsid = 0;
1107         cmd.common.cdw10[0] = cpu_to_le32(((u32)secp) << 24 | ((u32)spsp) << 8);
1108         cmd.common.cdw10[1] = cpu_to_le32(len);
1109
1110         return __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, NULL, buffer, len,
1111                                       ADMIN_TIMEOUT, NVME_QID_ANY, 1, 0);
1112 }
1113 EXPORT_SYMBOL_GPL(nvme_sec_submit);
1114 #endif /* CONFIG_BLK_SED_OPAL */
1115
1116 static const struct block_device_operations nvme_fops = {
1117         .owner          = THIS_MODULE,
1118         .ioctl          = nvme_ioctl,
1119         .compat_ioctl   = nvme_compat_ioctl,
1120         .open           = nvme_open,
1121         .release        = nvme_release,
1122         .getgeo         = nvme_getgeo,
1123         .revalidate_disk= nvme_revalidate_disk,
1124         .pr_ops         = &nvme_pr_ops,
1125 };
1126
1127 static int nvme_wait_ready(struct nvme_ctrl *ctrl, u64 cap, bool enabled)
1128 {
1129         unsigned long timeout =
1130                 ((NVME_CAP_TIMEOUT(cap) + 1) * HZ / 2) + jiffies;
1131         u32 csts, bit = enabled ? NVME_CSTS_RDY : 0;
1132         int ret;
1133
1134         while ((ret = ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &csts)) == 0) {
1135                 if (csts == ~0)
1136                         return -ENODEV;
1137                 if ((csts & NVME_CSTS_RDY) == bit)
1138                         break;
1139
1140                 msleep(100);
1141                 if (fatal_signal_pending(current))
1142                         return -EINTR;
1143                 if (time_after(jiffies, timeout)) {
1144                         dev_err(ctrl->device,
1145                                 "Device not ready; aborting %s\n", enabled ?
1146                                                 "initialisation" : "reset");
1147                         return -ENODEV;
1148                 }
1149         }
1150
1151         return ret;
1152 }
1153
1154 /*
1155  * If the device has been passed off to us in an enabled state, just clear
1156  * the enabled bit.  The spec says we should set the 'shutdown notification
1157  * bits', but doing so may cause the device to complete commands to the
1158  * admin queue ... and we don't know what memory that might be pointing at!
1159  */
1160 int nvme_disable_ctrl(struct nvme_ctrl *ctrl, u64 cap)
1161 {
1162         int ret;
1163
1164         ctrl->ctrl_config &= ~NVME_CC_SHN_MASK;
1165         ctrl->ctrl_config &= ~NVME_CC_ENABLE;
1166
1167         ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
1168         if (ret)
1169                 return ret;
1170
1171         if (ctrl->quirks & NVME_QUIRK_DELAY_BEFORE_CHK_RDY)
1172                 msleep(NVME_QUIRK_DELAY_AMOUNT);
1173
1174         return nvme_wait_ready(ctrl, cap, false);
1175 }
1176 EXPORT_SYMBOL_GPL(nvme_disable_ctrl);
1177
1178 int nvme_enable_ctrl(struct nvme_ctrl *ctrl, u64 cap)
1179 {
1180         /*
1181          * Default to a 4K page size, with the intention to update this
1182          * path in the future to accomodate architectures with differing
1183          * kernel and IO page sizes.
1184          */
1185         unsigned dev_page_min = NVME_CAP_MPSMIN(cap) + 12, page_shift = 12;
1186         int ret;
1187
1188         if (page_shift < dev_page_min) {
1189                 dev_err(ctrl->device,
1190                         "Minimum device page size %u too large for host (%u)\n",
1191                         1 << dev_page_min, 1 << page_shift);
1192                 return -ENODEV;
1193         }
1194
1195         ctrl->page_size = 1 << page_shift;
1196
1197         ctrl->ctrl_config = NVME_CC_CSS_NVM;
1198         ctrl->ctrl_config |= (page_shift - 12) << NVME_CC_MPS_SHIFT;
1199         ctrl->ctrl_config |= NVME_CC_ARB_RR | NVME_CC_SHN_NONE;
1200         ctrl->ctrl_config |= NVME_CC_IOSQES | NVME_CC_IOCQES;
1201         ctrl->ctrl_config |= NVME_CC_ENABLE;
1202
1203         ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
1204         if (ret)
1205                 return ret;
1206         return nvme_wait_ready(ctrl, cap, true);
1207 }
1208 EXPORT_SYMBOL_GPL(nvme_enable_ctrl);
1209
1210 int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl)
1211 {
1212         unsigned long timeout = SHUTDOWN_TIMEOUT + jiffies;
1213         u32 csts;
1214         int ret;
1215
1216         ctrl->ctrl_config &= ~NVME_CC_SHN_MASK;
1217         ctrl->ctrl_config |= NVME_CC_SHN_NORMAL;
1218
1219         ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
1220         if (ret)
1221                 return ret;
1222
1223         while ((ret = ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &csts)) == 0) {
1224                 if ((csts & NVME_CSTS_SHST_MASK) == NVME_CSTS_SHST_CMPLT)
1225                         break;
1226
1227                 msleep(100);
1228                 if (fatal_signal_pending(current))
1229                         return -EINTR;
1230                 if (time_after(jiffies, timeout)) {
1231                         dev_err(ctrl->device,
1232                                 "Device shutdown incomplete; abort shutdown\n");
1233                         return -ENODEV;
1234                 }
1235         }
1236
1237         return ret;
1238 }
1239 EXPORT_SYMBOL_GPL(nvme_shutdown_ctrl);
1240
1241 static void nvme_set_queue_limits(struct nvme_ctrl *ctrl,
1242                 struct request_queue *q)
1243 {
1244         bool vwc = false;
1245
1246         if (ctrl->max_hw_sectors) {
1247                 u32 max_segments =
1248                         (ctrl->max_hw_sectors / (ctrl->page_size >> 9)) + 1;
1249
1250                 blk_queue_max_hw_sectors(q, ctrl->max_hw_sectors);
1251                 blk_queue_max_segments(q, min_t(u32, max_segments, USHRT_MAX));
1252         }
1253         if (ctrl->quirks & NVME_QUIRK_STRIPE_SIZE)
1254                 blk_queue_chunk_sectors(q, ctrl->max_hw_sectors);
1255         blk_queue_virt_boundary(q, ctrl->page_size - 1);
1256         if (ctrl->vwc & NVME_CTRL_VWC_PRESENT)
1257                 vwc = true;
1258         blk_queue_write_cache(q, vwc, vwc);
1259 }
1260
1261 static void nvme_configure_apst(struct nvme_ctrl *ctrl)
1262 {
1263         /*
1264          * APST (Autonomous Power State Transition) lets us program a
1265          * table of power state transitions that the controller will
1266          * perform automatically.  We configure it with a simple
1267          * heuristic: we are willing to spend at most 2% of the time
1268          * transitioning between power states.  Therefore, when running
1269          * in any given state, we will enter the next lower-power
1270          * non-operational state after waiting 100 * (enlat + exlat)
1271          * microseconds, as long as that state's total latency is under
1272          * the requested maximum latency.
1273          *
1274          * We will not autonomously enter any non-operational state for
1275          * which the total latency exceeds ps_max_latency_us.  Users
1276          * can set ps_max_latency_us to zero to turn off APST.
1277          */
1278
1279         unsigned apste;
1280         struct nvme_feat_auto_pst *table;
1281         int ret;
1282
1283         /*
1284          * If APST isn't supported or if we haven't been initialized yet,
1285          * then don't do anything.
1286          */
1287         if (!ctrl->apsta)
1288                 return;
1289
1290         if (ctrl->npss > 31) {
1291                 dev_warn(ctrl->device, "NPSS is invalid; not using APST\n");
1292                 return;
1293         }
1294
1295         table = kzalloc(sizeof(*table), GFP_KERNEL);
1296         if (!table)
1297                 return;
1298
1299         if (ctrl->ps_max_latency_us == 0) {
1300                 /* Turn off APST. */
1301                 apste = 0;
1302         } else {
1303                 __le64 target = cpu_to_le64(0);
1304                 int state;
1305
1306                 /*
1307                  * Walk through all states from lowest- to highest-power.
1308                  * According to the spec, lower-numbered states use more
1309                  * power.  NPSS, despite the name, is the index of the
1310                  * lowest-power state, not the number of states.
1311                  */
1312                 for (state = (int)ctrl->npss; state >= 0; state--) {
1313                         u64 total_latency_us, transition_ms;
1314
1315                         if (target)
1316                                 table->entries[state] = target;
1317
1318                         /*
1319                          * Is this state a useful non-operational state for
1320                          * higher-power states to autonomously transition to?
1321                          */
1322                         if (!(ctrl->psd[state].flags &
1323                               NVME_PS_FLAGS_NON_OP_STATE))
1324                                 continue;
1325
1326                         total_latency_us =
1327                                 (u64)le32_to_cpu(ctrl->psd[state].entry_lat) +
1328                                 + le32_to_cpu(ctrl->psd[state].exit_lat);
1329                         if (total_latency_us > ctrl->ps_max_latency_us)
1330                                 continue;
1331
1332                         /*
1333                          * This state is good.  Use it as the APST idle
1334                          * target for higher power states.
1335                          */
1336                         transition_ms = total_latency_us + 19;
1337                         do_div(transition_ms, 20);
1338                         if (transition_ms > (1 << 24) - 1)
1339                                 transition_ms = (1 << 24) - 1;
1340
1341                         target = cpu_to_le64((state << 3) |
1342                                              (transition_ms << 8));
1343                 }
1344
1345                 apste = 1;
1346         }
1347
1348         ret = nvme_set_features(ctrl, NVME_FEAT_AUTO_PST, apste,
1349                                 table, sizeof(*table), NULL);
1350         if (ret)
1351                 dev_err(ctrl->device, "failed to set APST feature (%d)\n", ret);
1352
1353         kfree(table);
1354 }
1355
1356 static void nvme_set_latency_tolerance(struct device *dev, s32 val)
1357 {
1358         struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
1359         u64 latency;
1360
1361         switch (val) {
1362         case PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT:
1363         case PM_QOS_LATENCY_ANY:
1364                 latency = U64_MAX;
1365                 break;
1366
1367         default:
1368                 latency = val;
1369         }
1370
1371         if (ctrl->ps_max_latency_us != latency) {
1372                 ctrl->ps_max_latency_us = latency;
1373                 nvme_configure_apst(ctrl);
1374         }
1375 }
1376
1377 struct nvme_core_quirk_entry {
1378         /*
1379          * NVMe model and firmware strings are padded with spaces.  For
1380          * simplicity, strings in the quirk table are padded with NULLs
1381          * instead.
1382          */
1383         u16 vid;
1384         const char *mn;
1385         const char *fr;
1386         unsigned long quirks;
1387 };
1388
1389 static const struct nvme_core_quirk_entry core_quirks[] = {
1390         /*
1391          * Seen on a Samsung "SM951 NVMe SAMSUNG 256GB": using APST causes
1392          * the controller to go out to lunch.  It dies when the watchdog
1393          * timer reads CSTS and gets 0xffffffff.
1394          */
1395         {
1396                 .vid = 0x144d,
1397                 .fr = "BXW75D0Q",
1398                 .quirks = NVME_QUIRK_NO_APST,
1399         },
1400 };
1401
1402 /* match is null-terminated but idstr is space-padded. */
1403 static bool string_matches(const char *idstr, const char *match, size_t len)
1404 {
1405         size_t matchlen;
1406
1407         if (!match)
1408                 return true;
1409
1410         matchlen = strlen(match);
1411         WARN_ON_ONCE(matchlen > len);
1412
1413         if (memcmp(idstr, match, matchlen))
1414                 return false;
1415
1416         for (; matchlen < len; matchlen++)
1417                 if (idstr[matchlen] != ' ')
1418                         return false;
1419
1420         return true;
1421 }
1422
1423 static bool quirk_matches(const struct nvme_id_ctrl *id,
1424                           const struct nvme_core_quirk_entry *q)
1425 {
1426         return q->vid == le16_to_cpu(id->vid) &&
1427                 string_matches(id->mn, q->mn, sizeof(id->mn)) &&
1428                 string_matches(id->fr, q->fr, sizeof(id->fr));
1429 }
1430
1431 /*
1432  * Initialize the cached copies of the Identify data and various controller
1433  * register in our nvme_ctrl structure.  This should be called as soon as
1434  * the admin queue is fully up and running.
1435  */
1436 int nvme_init_identify(struct nvme_ctrl *ctrl)
1437 {
1438         struct nvme_id_ctrl *id;
1439         u64 cap;
1440         int ret, page_shift;
1441         u32 max_hw_sectors;
1442         u8 prev_apsta;
1443
1444         ret = ctrl->ops->reg_read32(ctrl, NVME_REG_VS, &ctrl->vs);
1445         if (ret) {
1446                 dev_err(ctrl->device, "Reading VS failed (%d)\n", ret);
1447                 return ret;
1448         }
1449
1450         ret = ctrl->ops->reg_read64(ctrl, NVME_REG_CAP, &cap);
1451         if (ret) {
1452                 dev_err(ctrl->device, "Reading CAP failed (%d)\n", ret);
1453                 return ret;
1454         }
1455         page_shift = NVME_CAP_MPSMIN(cap) + 12;
1456
1457         if (ctrl->vs >= NVME_VS(1, 1, 0))
1458                 ctrl->subsystem = NVME_CAP_NSSRC(cap);
1459
1460         ret = nvme_identify_ctrl(ctrl, &id);
1461         if (ret) {
1462                 dev_err(ctrl->device, "Identify Controller failed (%d)\n", ret);
1463                 return -EIO;
1464         }
1465
1466         if (!ctrl->identified) {
1467                 /*
1468                  * Check for quirks.  Quirk can depend on firmware version,
1469                  * so, in principle, the set of quirks present can change
1470                  * across a reset.  As a possible future enhancement, we
1471                  * could re-scan for quirks every time we reinitialize
1472                  * the device, but we'd have to make sure that the driver
1473                  * behaves intelligently if the quirks change.
1474                  */
1475
1476                 int i;
1477
1478                 for (i = 0; i < ARRAY_SIZE(core_quirks); i++) {
1479                         if (quirk_matches(id, &core_quirks[i]))
1480                                 ctrl->quirks |= core_quirks[i].quirks;
1481                 }
1482         }
1483
1484         ctrl->oacs = le16_to_cpu(id->oacs);
1485         ctrl->vid = le16_to_cpu(id->vid);
1486         ctrl->oncs = le16_to_cpup(&id->oncs);
1487         atomic_set(&ctrl->abort_limit, id->acl + 1);
1488         ctrl->vwc = id->vwc;
1489         ctrl->cntlid = le16_to_cpup(&id->cntlid);
1490         memcpy(ctrl->serial, id->sn, sizeof(id->sn));
1491         memcpy(ctrl->model, id->mn, sizeof(id->mn));
1492         memcpy(ctrl->firmware_rev, id->fr, sizeof(id->fr));
1493         if (id->mdts)
1494                 max_hw_sectors = 1 << (id->mdts + page_shift - 9);
1495         else
1496                 max_hw_sectors = UINT_MAX;
1497         ctrl->max_hw_sectors =
1498                 min_not_zero(ctrl->max_hw_sectors, max_hw_sectors);
1499
1500         nvme_set_queue_limits(ctrl, ctrl->admin_q);
1501         ctrl->sgls = le32_to_cpu(id->sgls);
1502         ctrl->kas = le16_to_cpu(id->kas);
1503
1504         ctrl->npss = id->npss;
1505         prev_apsta = ctrl->apsta;
1506         ctrl->apsta = (ctrl->quirks & NVME_QUIRK_NO_APST) ? 0 : id->apsta;
1507         memcpy(ctrl->psd, id->psd, sizeof(ctrl->psd));
1508
1509         if (ctrl->ops->is_fabrics) {
1510                 ctrl->icdoff = le16_to_cpu(id->icdoff);
1511                 ctrl->ioccsz = le32_to_cpu(id->ioccsz);
1512                 ctrl->iorcsz = le32_to_cpu(id->iorcsz);
1513                 ctrl->maxcmd = le16_to_cpu(id->maxcmd);
1514
1515                 /*
1516                  * In fabrics we need to verify the cntlid matches the
1517                  * admin connect
1518                  */
1519                 if (ctrl->cntlid != le16_to_cpu(id->cntlid))
1520                         ret = -EINVAL;
1521
1522                 if (!ctrl->opts->discovery_nqn && !ctrl->kas) {
1523                         dev_err(ctrl->dev,
1524                                 "keep-alive support is mandatory for fabrics\n");
1525                         ret = -EINVAL;
1526                 }
1527         } else {
1528                 ctrl->cntlid = le16_to_cpu(id->cntlid);
1529         }
1530
1531         kfree(id);
1532
1533         if (ctrl->apsta && !prev_apsta)
1534                 dev_pm_qos_expose_latency_tolerance(ctrl->device);
1535         else if (!ctrl->apsta && prev_apsta)
1536                 dev_pm_qos_hide_latency_tolerance(ctrl->device);
1537
1538         nvme_configure_apst(ctrl);
1539
1540         ctrl->identified = true;
1541
1542         return ret;
1543 }
1544 EXPORT_SYMBOL_GPL(nvme_init_identify);
1545
1546 static int nvme_dev_open(struct inode *inode, struct file *file)
1547 {
1548         struct nvme_ctrl *ctrl;
1549         int instance = iminor(inode);
1550         int ret = -ENODEV;
1551
1552         spin_lock(&dev_list_lock);
1553         list_for_each_entry(ctrl, &nvme_ctrl_list, node) {
1554                 if (ctrl->instance != instance)
1555                         continue;
1556
1557                 if (!ctrl->admin_q) {
1558                         ret = -EWOULDBLOCK;
1559                         break;
1560                 }
1561                 if (!kref_get_unless_zero(&ctrl->kref))
1562                         break;
1563                 file->private_data = ctrl;
1564                 ret = 0;
1565                 break;
1566         }
1567         spin_unlock(&dev_list_lock);
1568
1569         return ret;
1570 }
1571
1572 static int nvme_dev_release(struct inode *inode, struct file *file)
1573 {
1574         nvme_put_ctrl(file->private_data);
1575         return 0;
1576 }
1577
1578 static int nvme_dev_user_cmd(struct nvme_ctrl *ctrl, void __user *argp)
1579 {
1580         struct nvme_ns *ns;
1581         int ret;
1582
1583         mutex_lock(&ctrl->namespaces_mutex);
1584         if (list_empty(&ctrl->namespaces)) {
1585                 ret = -ENOTTY;
1586                 goto out_unlock;
1587         }
1588
1589         ns = list_first_entry(&ctrl->namespaces, struct nvme_ns, list);
1590         if (ns != list_last_entry(&ctrl->namespaces, struct nvme_ns, list)) {
1591                 dev_warn(ctrl->device,
1592                         "NVME_IOCTL_IO_CMD not supported when multiple namespaces present!\n");
1593                 ret = -EINVAL;
1594                 goto out_unlock;
1595         }
1596
1597         dev_warn(ctrl->device,
1598                 "using deprecated NVME_IOCTL_IO_CMD ioctl on the char device!\n");
1599         kref_get(&ns->kref);
1600         mutex_unlock(&ctrl->namespaces_mutex);
1601
1602         ret = nvme_user_cmd(ctrl, ns, argp);
1603         nvme_put_ns(ns);
1604         return ret;
1605
1606 out_unlock:
1607         mutex_unlock(&ctrl->namespaces_mutex);
1608         return ret;
1609 }
1610
1611 static long nvme_dev_ioctl(struct file *file, unsigned int cmd,
1612                 unsigned long arg)
1613 {
1614         struct nvme_ctrl *ctrl = file->private_data;
1615         void __user *argp = (void __user *)arg;
1616
1617         switch (cmd) {
1618         case NVME_IOCTL_ADMIN_CMD:
1619                 return nvme_user_cmd(ctrl, NULL, argp);
1620         case NVME_IOCTL_IO_CMD:
1621                 return nvme_dev_user_cmd(ctrl, argp);
1622         case NVME_IOCTL_RESET:
1623                 dev_warn(ctrl->device, "resetting controller\n");
1624                 return ctrl->ops->reset_ctrl(ctrl);
1625         case NVME_IOCTL_SUBSYS_RESET:
1626                 return nvme_reset_subsystem(ctrl);
1627         case NVME_IOCTL_RESCAN:
1628                 nvme_queue_scan(ctrl);
1629                 return 0;
1630         default:
1631                 return -ENOTTY;
1632         }
1633 }
1634
1635 static const struct file_operations nvme_dev_fops = {
1636         .owner          = THIS_MODULE,
1637         .open           = nvme_dev_open,
1638         .release        = nvme_dev_release,
1639         .unlocked_ioctl = nvme_dev_ioctl,
1640         .compat_ioctl   = nvme_dev_ioctl,
1641 };
1642
1643 static ssize_t nvme_sysfs_reset(struct device *dev,
1644                                 struct device_attribute *attr, const char *buf,
1645                                 size_t count)
1646 {
1647         struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
1648         int ret;
1649
1650         ret = ctrl->ops->reset_ctrl(ctrl);
1651         if (ret < 0)
1652                 return ret;
1653         return count;
1654 }
1655 static DEVICE_ATTR(reset_controller, S_IWUSR, NULL, nvme_sysfs_reset);
1656
1657 static ssize_t nvme_sysfs_rescan(struct device *dev,
1658                                 struct device_attribute *attr, const char *buf,
1659                                 size_t count)
1660 {
1661         struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
1662
1663         nvme_queue_scan(ctrl);
1664         return count;
1665 }
1666 static DEVICE_ATTR(rescan_controller, S_IWUSR, NULL, nvme_sysfs_rescan);
1667
1668 static ssize_t wwid_show(struct device *dev, struct device_attribute *attr,
1669                                                                 char *buf)
1670 {
1671         struct nvme_ns *ns = nvme_get_ns_from_dev(dev);
1672         struct nvme_ctrl *ctrl = ns->ctrl;
1673         int serial_len = sizeof(ctrl->serial);
1674         int model_len = sizeof(ctrl->model);
1675
1676         if (memchr_inv(ns->uuid, 0, sizeof(ns->uuid)))
1677                 return sprintf(buf, "eui.%16phN\n", ns->uuid);
1678
1679         if (memchr_inv(ns->eui, 0, sizeof(ns->eui)))
1680                 return sprintf(buf, "eui.%8phN\n", ns->eui);
1681
1682         while (ctrl->serial[serial_len - 1] == ' ')
1683                 serial_len--;
1684         while (ctrl->model[model_len - 1] == ' ')
1685                 model_len--;
1686
1687         return sprintf(buf, "nvme.%04x-%*phN-%*phN-%08x\n", ctrl->vid,
1688                 serial_len, ctrl->serial, model_len, ctrl->model, ns->ns_id);
1689 }
1690 static DEVICE_ATTR(wwid, S_IRUGO, wwid_show, NULL);
1691
1692 static ssize_t uuid_show(struct device *dev, struct device_attribute *attr,
1693                                                                 char *buf)
1694 {
1695         struct nvme_ns *ns = nvme_get_ns_from_dev(dev);
1696         return sprintf(buf, "%pU\n", ns->uuid);
1697 }
1698 static DEVICE_ATTR(uuid, S_IRUGO, uuid_show, NULL);
1699
1700 static ssize_t eui_show(struct device *dev, struct device_attribute *attr,
1701                                                                 char *buf)
1702 {
1703         struct nvme_ns *ns = nvme_get_ns_from_dev(dev);
1704         return sprintf(buf, "%8phd\n", ns->eui);
1705 }
1706 static DEVICE_ATTR(eui, S_IRUGO, eui_show, NULL);
1707
1708 static ssize_t nsid_show(struct device *dev, struct device_attribute *attr,
1709                                                                 char *buf)
1710 {
1711         struct nvme_ns *ns = nvme_get_ns_from_dev(dev);
1712         return sprintf(buf, "%d\n", ns->ns_id);
1713 }
1714 static DEVICE_ATTR(nsid, S_IRUGO, nsid_show, NULL);
1715
1716 static struct attribute *nvme_ns_attrs[] = {
1717         &dev_attr_wwid.attr,
1718         &dev_attr_uuid.attr,
1719         &dev_attr_eui.attr,
1720         &dev_attr_nsid.attr,
1721         NULL,
1722 };
1723
1724 static umode_t nvme_ns_attrs_are_visible(struct kobject *kobj,
1725                 struct attribute *a, int n)
1726 {
1727         struct device *dev = container_of(kobj, struct device, kobj);
1728         struct nvme_ns *ns = nvme_get_ns_from_dev(dev);
1729
1730         if (a == &dev_attr_uuid.attr) {
1731                 if (!memchr_inv(ns->uuid, 0, sizeof(ns->uuid)))
1732                         return 0;
1733         }
1734         if (a == &dev_attr_eui.attr) {
1735                 if (!memchr_inv(ns->eui, 0, sizeof(ns->eui)))
1736                         return 0;
1737         }
1738         return a->mode;
1739 }
1740
1741 static const struct attribute_group nvme_ns_attr_group = {
1742         .attrs          = nvme_ns_attrs,
1743         .is_visible     = nvme_ns_attrs_are_visible,
1744 };
1745
1746 #define nvme_show_str_function(field)                                           \
1747 static ssize_t  field##_show(struct device *dev,                                \
1748                             struct device_attribute *attr, char *buf)           \
1749 {                                                                               \
1750         struct nvme_ctrl *ctrl = dev_get_drvdata(dev);                          \
1751         return sprintf(buf, "%.*s\n", (int)sizeof(ctrl->field), ctrl->field);   \
1752 }                                                                               \
1753 static DEVICE_ATTR(field, S_IRUGO, field##_show, NULL);
1754
1755 #define nvme_show_int_function(field)                                           \
1756 static ssize_t  field##_show(struct device *dev,                                \
1757                             struct device_attribute *attr, char *buf)           \
1758 {                                                                               \
1759         struct nvme_ctrl *ctrl = dev_get_drvdata(dev);                          \
1760         return sprintf(buf, "%d\n", ctrl->field);       \
1761 }                                                                               \
1762 static DEVICE_ATTR(field, S_IRUGO, field##_show, NULL);
1763
1764 nvme_show_str_function(model);
1765 nvme_show_str_function(serial);
1766 nvme_show_str_function(firmware_rev);
1767 nvme_show_int_function(cntlid);
1768
1769 static ssize_t nvme_sysfs_delete(struct device *dev,
1770                                 struct device_attribute *attr, const char *buf,
1771                                 size_t count)
1772 {
1773         struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
1774
1775         if (device_remove_file_self(dev, attr))
1776                 ctrl->ops->delete_ctrl(ctrl);
1777         return count;
1778 }
1779 static DEVICE_ATTR(delete_controller, S_IWUSR, NULL, nvme_sysfs_delete);
1780
1781 static ssize_t nvme_sysfs_show_transport(struct device *dev,
1782                                          struct device_attribute *attr,
1783                                          char *buf)
1784 {
1785         struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
1786
1787         return snprintf(buf, PAGE_SIZE, "%s\n", ctrl->ops->name);
1788 }
1789 static DEVICE_ATTR(transport, S_IRUGO, nvme_sysfs_show_transport, NULL);
1790
1791 static ssize_t nvme_sysfs_show_state(struct device *dev,
1792                                      struct device_attribute *attr,
1793                                      char *buf)
1794 {
1795         struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
1796         static const char *const state_name[] = {
1797                 [NVME_CTRL_NEW]         = "new",
1798                 [NVME_CTRL_LIVE]        = "live",
1799                 [NVME_CTRL_RESETTING]   = "resetting",
1800                 [NVME_CTRL_RECONNECTING]= "reconnecting",
1801                 [NVME_CTRL_DELETING]    = "deleting",
1802                 [NVME_CTRL_DEAD]        = "dead",
1803         };
1804
1805         if ((unsigned)ctrl->state < ARRAY_SIZE(state_name) &&
1806             state_name[ctrl->state])
1807                 return sprintf(buf, "%s\n", state_name[ctrl->state]);
1808
1809         return sprintf(buf, "unknown state\n");
1810 }
1811
1812 static DEVICE_ATTR(state, S_IRUGO, nvme_sysfs_show_state, NULL);
1813
1814 static ssize_t nvme_sysfs_show_subsysnqn(struct device *dev,
1815                                          struct device_attribute *attr,
1816                                          char *buf)
1817 {
1818         struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
1819
1820         return snprintf(buf, PAGE_SIZE, "%s\n",
1821                         ctrl->ops->get_subsysnqn(ctrl));
1822 }
1823 static DEVICE_ATTR(subsysnqn, S_IRUGO, nvme_sysfs_show_subsysnqn, NULL);
1824
1825 static ssize_t nvme_sysfs_show_address(struct device *dev,
1826                                          struct device_attribute *attr,
1827                                          char *buf)
1828 {
1829         struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
1830
1831         return ctrl->ops->get_address(ctrl, buf, PAGE_SIZE);
1832 }
1833 static DEVICE_ATTR(address, S_IRUGO, nvme_sysfs_show_address, NULL);
1834
1835 static struct attribute *nvme_dev_attrs[] = {
1836         &dev_attr_reset_controller.attr,
1837         &dev_attr_rescan_controller.attr,
1838         &dev_attr_model.attr,
1839         &dev_attr_serial.attr,
1840         &dev_attr_firmware_rev.attr,
1841         &dev_attr_cntlid.attr,
1842         &dev_attr_delete_controller.attr,
1843         &dev_attr_transport.attr,
1844         &dev_attr_subsysnqn.attr,
1845         &dev_attr_address.attr,
1846         &dev_attr_state.attr,
1847         NULL
1848 };
1849
1850 #define CHECK_ATTR(ctrl, a, name)               \
1851         if ((a) == &dev_attr_##name.attr &&     \
1852             !(ctrl)->ops->get_##name)           \
1853                 return 0
1854
1855 static umode_t nvme_dev_attrs_are_visible(struct kobject *kobj,
1856                 struct attribute *a, int n)
1857 {
1858         struct device *dev = container_of(kobj, struct device, kobj);
1859         struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
1860
1861         if (a == &dev_attr_delete_controller.attr) {
1862                 if (!ctrl->ops->delete_ctrl)
1863                         return 0;
1864         }
1865
1866         CHECK_ATTR(ctrl, a, subsysnqn);
1867         CHECK_ATTR(ctrl, a, address);
1868
1869         return a->mode;
1870 }
1871
1872 static struct attribute_group nvme_dev_attrs_group = {
1873         .attrs          = nvme_dev_attrs,
1874         .is_visible     = nvme_dev_attrs_are_visible,
1875 };
1876
1877 static const struct attribute_group *nvme_dev_attr_groups[] = {
1878         &nvme_dev_attrs_group,
1879         NULL,
1880 };
1881
1882 static int ns_cmp(void *priv, struct list_head *a, struct list_head *b)
1883 {
1884         struct nvme_ns *nsa = container_of(a, struct nvme_ns, list);
1885         struct nvme_ns *nsb = container_of(b, struct nvme_ns, list);
1886
1887         return nsa->ns_id - nsb->ns_id;
1888 }
1889
1890 static struct nvme_ns *nvme_find_get_ns(struct nvme_ctrl *ctrl, unsigned nsid)
1891 {
1892         struct nvme_ns *ns, *ret = NULL;
1893
1894         mutex_lock(&ctrl->namespaces_mutex);
1895         list_for_each_entry(ns, &ctrl->namespaces, list) {
1896                 if (ns->ns_id == nsid) {
1897                         kref_get(&ns->kref);
1898                         ret = ns;
1899                         break;
1900                 }
1901                 if (ns->ns_id > nsid)
1902                         break;
1903         }
1904         mutex_unlock(&ctrl->namespaces_mutex);
1905         return ret;
1906 }
1907
1908 static void nvme_alloc_ns(struct nvme_ctrl *ctrl, unsigned nsid)
1909 {
1910         struct nvme_ns *ns;
1911         struct gendisk *disk;
1912         struct nvme_id_ns *id;
1913         char disk_name[DISK_NAME_LEN];
1914         int node = dev_to_node(ctrl->dev);
1915
1916         ns = kzalloc_node(sizeof(*ns), GFP_KERNEL, node);
1917         if (!ns)
1918                 return;
1919
1920         ns->instance = ida_simple_get(&ctrl->ns_ida, 1, 0, GFP_KERNEL);
1921         if (ns->instance < 0)
1922                 goto out_free_ns;
1923
1924         ns->queue = blk_mq_init_queue(ctrl->tagset);
1925         if (IS_ERR(ns->queue))
1926                 goto out_release_instance;
1927         queue_flag_set_unlocked(QUEUE_FLAG_NONROT, ns->queue);
1928         ns->queue->queuedata = ns;
1929         ns->ctrl = ctrl;
1930
1931         kref_init(&ns->kref);
1932         ns->ns_id = nsid;
1933         ns->lba_shift = 9; /* set to a default value for 512 until disk is validated */
1934
1935         blk_queue_logical_block_size(ns->queue, 1 << ns->lba_shift);
1936         nvme_set_queue_limits(ctrl, ns->queue);
1937
1938         sprintf(disk_name, "nvme%dn%d", ctrl->instance, ns->instance);
1939
1940         if (nvme_revalidate_ns(ns, &id))
1941                 goto out_free_queue;
1942
1943         if (nvme_nvm_ns_supported(ns, id) &&
1944                                 nvme_nvm_register(ns, disk_name, node)) {
1945                 dev_warn(ctrl->dev, "%s: LightNVM init failure\n", __func__);
1946                 goto out_free_id;
1947         }
1948
1949         disk = alloc_disk_node(0, node);
1950         if (!disk)
1951                 goto out_free_id;
1952
1953         disk->fops = &nvme_fops;
1954         disk->private_data = ns;
1955         disk->queue = ns->queue;
1956         disk->flags = GENHD_FL_EXT_DEVT;
1957         memcpy(disk->disk_name, disk_name, DISK_NAME_LEN);
1958         ns->disk = disk;
1959
1960         __nvme_revalidate_disk(disk, id);
1961
1962         mutex_lock(&ctrl->namespaces_mutex);
1963         list_add_tail(&ns->list, &ctrl->namespaces);
1964         mutex_unlock(&ctrl->namespaces_mutex);
1965
1966         kref_get(&ctrl->kref);
1967
1968         kfree(id);
1969
1970         device_add_disk(ctrl->device, ns->disk);
1971         if (sysfs_create_group(&disk_to_dev(ns->disk)->kobj,
1972                                         &nvme_ns_attr_group))
1973                 pr_warn("%s: failed to create sysfs group for identification\n",
1974                         ns->disk->disk_name);
1975         if (ns->ndev && nvme_nvm_register_sysfs(ns))
1976                 pr_warn("%s: failed to register lightnvm sysfs group for identification\n",
1977                         ns->disk->disk_name);
1978         return;
1979  out_free_id:
1980         kfree(id);
1981  out_free_queue:
1982         blk_cleanup_queue(ns->queue);
1983  out_release_instance:
1984         ida_simple_remove(&ctrl->ns_ida, ns->instance);
1985  out_free_ns:
1986         kfree(ns);
1987 }
1988
1989 static void nvme_ns_remove(struct nvme_ns *ns)
1990 {
1991         if (test_and_set_bit(NVME_NS_REMOVING, &ns->flags))
1992                 return;
1993
1994         if (ns->disk && ns->disk->flags & GENHD_FL_UP) {
1995                 if (blk_get_integrity(ns->disk))
1996                         blk_integrity_unregister(ns->disk);
1997                 sysfs_remove_group(&disk_to_dev(ns->disk)->kobj,
1998                                         &nvme_ns_attr_group);
1999                 if (ns->ndev)
2000                         nvme_nvm_unregister_sysfs(ns);
2001                 del_gendisk(ns->disk);
2002                 blk_mq_abort_requeue_list(ns->queue);
2003                 blk_cleanup_queue(ns->queue);
2004         }
2005
2006         mutex_lock(&ns->ctrl->namespaces_mutex);
2007         list_del_init(&ns->list);
2008         mutex_unlock(&ns->ctrl->namespaces_mutex);
2009
2010         nvme_put_ns(ns);
2011 }
2012
2013 static void nvme_validate_ns(struct nvme_ctrl *ctrl, unsigned nsid)
2014 {
2015         struct nvme_ns *ns;
2016
2017         ns = nvme_find_get_ns(ctrl, nsid);
2018         if (ns) {
2019                 if (ns->disk && revalidate_disk(ns->disk))
2020                         nvme_ns_remove(ns);
2021                 nvme_put_ns(ns);
2022         } else
2023                 nvme_alloc_ns(ctrl, nsid);
2024 }
2025
2026 static void nvme_remove_invalid_namespaces(struct nvme_ctrl *ctrl,
2027                                         unsigned nsid)
2028 {
2029         struct nvme_ns *ns, *next;
2030
2031         list_for_each_entry_safe(ns, next, &ctrl->namespaces, list) {
2032                 if (ns->ns_id > nsid)
2033                         nvme_ns_remove(ns);
2034         }
2035 }
2036
2037 static int nvme_scan_ns_list(struct nvme_ctrl *ctrl, unsigned nn)
2038 {
2039         struct nvme_ns *ns;
2040         __le32 *ns_list;
2041         unsigned i, j, nsid, prev = 0, num_lists = DIV_ROUND_UP(nn, 1024);
2042         int ret = 0;
2043
2044         ns_list = kzalloc(0x1000, GFP_KERNEL);
2045         if (!ns_list)
2046                 return -ENOMEM;
2047
2048         for (i = 0; i < num_lists; i++) {
2049                 ret = nvme_identify_ns_list(ctrl, prev, ns_list);
2050                 if (ret)
2051                         goto free;
2052
2053                 for (j = 0; j < min(nn, 1024U); j++) {
2054                         nsid = le32_to_cpu(ns_list[j]);
2055                         if (!nsid)
2056                                 goto out;
2057
2058                         nvme_validate_ns(ctrl, nsid);
2059
2060                         while (++prev < nsid) {
2061                                 ns = nvme_find_get_ns(ctrl, prev);
2062                                 if (ns) {
2063                                         nvme_ns_remove(ns);
2064                                         nvme_put_ns(ns);
2065                                 }
2066                         }
2067                 }
2068                 nn -= j;
2069         }
2070  out:
2071         nvme_remove_invalid_namespaces(ctrl, prev);
2072  free:
2073         kfree(ns_list);
2074         return ret;
2075 }
2076
2077 static void nvme_scan_ns_sequential(struct nvme_ctrl *ctrl, unsigned nn)
2078 {
2079         unsigned i;
2080
2081         for (i = 1; i <= nn; i++)
2082                 nvme_validate_ns(ctrl, i);
2083
2084         nvme_remove_invalid_namespaces(ctrl, nn);
2085 }
2086
2087 static void nvme_scan_work(struct work_struct *work)
2088 {
2089         struct nvme_ctrl *ctrl =
2090                 container_of(work, struct nvme_ctrl, scan_work);
2091         struct nvme_id_ctrl *id;
2092         unsigned nn;
2093
2094         if (ctrl->state != NVME_CTRL_LIVE)
2095                 return;
2096
2097         if (nvme_identify_ctrl(ctrl, &id))
2098                 return;
2099
2100         nn = le32_to_cpu(id->nn);
2101         if (ctrl->vs >= NVME_VS(1, 1, 0) &&
2102             !(ctrl->quirks & NVME_QUIRK_IDENTIFY_CNS)) {
2103                 if (!nvme_scan_ns_list(ctrl, nn))
2104                         goto done;
2105         }
2106         nvme_scan_ns_sequential(ctrl, nn);
2107  done:
2108         mutex_lock(&ctrl->namespaces_mutex);
2109         list_sort(NULL, &ctrl->namespaces, ns_cmp);
2110         mutex_unlock(&ctrl->namespaces_mutex);
2111         kfree(id);
2112 }
2113
2114 void nvme_queue_scan(struct nvme_ctrl *ctrl)
2115 {
2116         /*
2117          * Do not queue new scan work when a controller is reset during
2118          * removal.
2119          */
2120         if (ctrl->state == NVME_CTRL_LIVE)
2121                 schedule_work(&ctrl->scan_work);
2122 }
2123 EXPORT_SYMBOL_GPL(nvme_queue_scan);
2124
2125 /*
2126  * This function iterates the namespace list unlocked to allow recovery from
2127  * controller failure. It is up to the caller to ensure the namespace list is
2128  * not modified by scan work while this function is executing.
2129  */
2130 void nvme_remove_namespaces(struct nvme_ctrl *ctrl)
2131 {
2132         struct nvme_ns *ns, *next;
2133
2134         /*
2135          * The dead states indicates the controller was not gracefully
2136          * disconnected. In that case, we won't be able to flush any data while
2137          * removing the namespaces' disks; fail all the queues now to avoid
2138          * potentially having to clean up the failed sync later.
2139          */
2140         if (ctrl->state == NVME_CTRL_DEAD)
2141                 nvme_kill_queues(ctrl);
2142
2143         list_for_each_entry_safe(ns, next, &ctrl->namespaces, list)
2144                 nvme_ns_remove(ns);
2145 }
2146 EXPORT_SYMBOL_GPL(nvme_remove_namespaces);
2147
2148 static void nvme_async_event_work(struct work_struct *work)
2149 {
2150         struct nvme_ctrl *ctrl =
2151                 container_of(work, struct nvme_ctrl, async_event_work);
2152
2153         spin_lock_irq(&ctrl->lock);
2154         while (ctrl->event_limit > 0) {
2155                 int aer_idx = --ctrl->event_limit;
2156
2157                 spin_unlock_irq(&ctrl->lock);
2158                 ctrl->ops->submit_async_event(ctrl, aer_idx);
2159                 spin_lock_irq(&ctrl->lock);
2160         }
2161         spin_unlock_irq(&ctrl->lock);
2162 }
2163
2164 void nvme_complete_async_event(struct nvme_ctrl *ctrl, __le16 status,
2165                 union nvme_result *res)
2166 {
2167         u32 result = le32_to_cpu(res->u32);
2168         bool done = true;
2169
2170         switch (le16_to_cpu(status) >> 1) {
2171         case NVME_SC_SUCCESS:
2172                 done = false;
2173                 /*FALLTHRU*/
2174         case NVME_SC_ABORT_REQ:
2175                 ++ctrl->event_limit;
2176                 schedule_work(&ctrl->async_event_work);
2177                 break;
2178         default:
2179                 break;
2180         }
2181
2182         if (done)
2183                 return;
2184
2185         switch (result & 0xff07) {
2186         case NVME_AER_NOTICE_NS_CHANGED:
2187                 dev_info(ctrl->device, "rescanning\n");
2188                 nvme_queue_scan(ctrl);
2189                 break;
2190         default:
2191                 dev_warn(ctrl->device, "async event result %08x\n", result);
2192         }
2193 }
2194 EXPORT_SYMBOL_GPL(nvme_complete_async_event);
2195
2196 void nvme_queue_async_events(struct nvme_ctrl *ctrl)
2197 {
2198         ctrl->event_limit = NVME_NR_AERS;
2199         schedule_work(&ctrl->async_event_work);
2200 }
2201 EXPORT_SYMBOL_GPL(nvme_queue_async_events);
2202
2203 static DEFINE_IDA(nvme_instance_ida);
2204
2205 static int nvme_set_instance(struct nvme_ctrl *ctrl)
2206 {
2207         int instance, error;
2208
2209         do {
2210                 if (!ida_pre_get(&nvme_instance_ida, GFP_KERNEL))
2211                         return -ENODEV;
2212
2213                 spin_lock(&dev_list_lock);
2214                 error = ida_get_new(&nvme_instance_ida, &instance);
2215                 spin_unlock(&dev_list_lock);
2216         } while (error == -EAGAIN);
2217
2218         if (error)
2219                 return -ENODEV;
2220
2221         ctrl->instance = instance;
2222         return 0;
2223 }
2224
2225 static void nvme_release_instance(struct nvme_ctrl *ctrl)
2226 {
2227         spin_lock(&dev_list_lock);
2228         ida_remove(&nvme_instance_ida, ctrl->instance);
2229         spin_unlock(&dev_list_lock);
2230 }
2231
2232 void nvme_uninit_ctrl(struct nvme_ctrl *ctrl)
2233 {
2234         flush_work(&ctrl->async_event_work);
2235         flush_work(&ctrl->scan_work);
2236         nvme_remove_namespaces(ctrl);
2237
2238         device_destroy(nvme_class, MKDEV(nvme_char_major, ctrl->instance));
2239
2240         spin_lock(&dev_list_lock);
2241         list_del(&ctrl->node);
2242         spin_unlock(&dev_list_lock);
2243 }
2244 EXPORT_SYMBOL_GPL(nvme_uninit_ctrl);
2245
2246 static void nvme_free_ctrl(struct kref *kref)
2247 {
2248         struct nvme_ctrl *ctrl = container_of(kref, struct nvme_ctrl, kref);
2249
2250         put_device(ctrl->device);
2251         nvme_release_instance(ctrl);
2252         ida_destroy(&ctrl->ns_ida);
2253
2254         ctrl->ops->free_ctrl(ctrl);
2255 }
2256
2257 void nvme_put_ctrl(struct nvme_ctrl *ctrl)
2258 {
2259         kref_put(&ctrl->kref, nvme_free_ctrl);
2260 }
2261 EXPORT_SYMBOL_GPL(nvme_put_ctrl);
2262
2263 /*
2264  * Initialize a NVMe controller structures.  This needs to be called during
2265  * earliest initialization so that we have the initialized structured around
2266  * during probing.
2267  */
2268 int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
2269                 const struct nvme_ctrl_ops *ops, unsigned long quirks)
2270 {
2271         int ret;
2272
2273         ctrl->state = NVME_CTRL_NEW;
2274         spin_lock_init(&ctrl->lock);
2275         INIT_LIST_HEAD(&ctrl->namespaces);
2276         mutex_init(&ctrl->namespaces_mutex);
2277         kref_init(&ctrl->kref);
2278         ctrl->dev = dev;
2279         ctrl->ops = ops;
2280         ctrl->quirks = quirks;
2281         INIT_WORK(&ctrl->scan_work, nvme_scan_work);
2282         INIT_WORK(&ctrl->async_event_work, nvme_async_event_work);
2283
2284         ret = nvme_set_instance(ctrl);
2285         if (ret)
2286                 goto out;
2287
2288         ctrl->device = device_create_with_groups(nvme_class, ctrl->dev,
2289                                 MKDEV(nvme_char_major, ctrl->instance),
2290                                 ctrl, nvme_dev_attr_groups,
2291                                 "nvme%d", ctrl->instance);
2292         if (IS_ERR(ctrl->device)) {
2293                 ret = PTR_ERR(ctrl->device);
2294                 goto out_release_instance;
2295         }
2296         get_device(ctrl->device);
2297         ida_init(&ctrl->ns_ida);
2298
2299         spin_lock(&dev_list_lock);
2300         list_add_tail(&ctrl->node, &nvme_ctrl_list);
2301         spin_unlock(&dev_list_lock);
2302
2303         /*
2304          * Initialize latency tolerance controls.  The sysfs files won't
2305          * be visible to userspace unless the device actually supports APST.
2306          */
2307         ctrl->device->power.set_latency_tolerance = nvme_set_latency_tolerance;
2308         dev_pm_qos_update_user_latency_tolerance(ctrl->device,
2309                 min(default_ps_max_latency_us, (unsigned long)S32_MAX));
2310
2311         return 0;
2312 out_release_instance:
2313         nvme_release_instance(ctrl);
2314 out:
2315         return ret;
2316 }
2317 EXPORT_SYMBOL_GPL(nvme_init_ctrl);
2318
2319 /**
2320  * nvme_kill_queues(): Ends all namespace queues
2321  * @ctrl: the dead controller that needs to end
2322  *
2323  * Call this function when the driver determines it is unable to get the
2324  * controller in a state capable of servicing IO.
2325  */
2326 void nvme_kill_queues(struct nvme_ctrl *ctrl)
2327 {
2328         struct nvme_ns *ns;
2329
2330         mutex_lock(&ctrl->namespaces_mutex);
2331         list_for_each_entry(ns, &ctrl->namespaces, list) {
2332                 /*
2333                  * Revalidating a dead namespace sets capacity to 0. This will
2334                  * end buffered writers dirtying pages that can't be synced.
2335                  */
2336                 if (!ns->disk || test_and_set_bit(NVME_NS_DEAD, &ns->flags))
2337                         continue;
2338                 revalidate_disk(ns->disk);
2339                 blk_set_queue_dying(ns->queue);
2340                 blk_mq_abort_requeue_list(ns->queue);
2341                 blk_mq_start_stopped_hw_queues(ns->queue, true);
2342         }
2343         mutex_unlock(&ctrl->namespaces_mutex);
2344 }
2345 EXPORT_SYMBOL_GPL(nvme_kill_queues);
2346
2347 void nvme_unfreeze(struct nvme_ctrl *ctrl)
2348 {
2349         struct nvme_ns *ns;
2350
2351         mutex_lock(&ctrl->namespaces_mutex);
2352         list_for_each_entry(ns, &ctrl->namespaces, list)
2353                 blk_mq_unfreeze_queue(ns->queue);
2354         mutex_unlock(&ctrl->namespaces_mutex);
2355 }
2356 EXPORT_SYMBOL_GPL(nvme_unfreeze);
2357
2358 void nvme_wait_freeze_timeout(struct nvme_ctrl *ctrl, long timeout)
2359 {
2360         struct nvme_ns *ns;
2361
2362         mutex_lock(&ctrl->namespaces_mutex);
2363         list_for_each_entry(ns, &ctrl->namespaces, list) {
2364                 timeout = blk_mq_freeze_queue_wait_timeout(ns->queue, timeout);
2365                 if (timeout <= 0)
2366                         break;
2367         }
2368         mutex_unlock(&ctrl->namespaces_mutex);
2369 }
2370 EXPORT_SYMBOL_GPL(nvme_wait_freeze_timeout);
2371
2372 void nvme_wait_freeze(struct nvme_ctrl *ctrl)
2373 {
2374         struct nvme_ns *ns;
2375
2376         mutex_lock(&ctrl->namespaces_mutex);
2377         list_for_each_entry(ns, &ctrl->namespaces, list)
2378                 blk_mq_freeze_queue_wait(ns->queue);
2379         mutex_unlock(&ctrl->namespaces_mutex);
2380 }
2381 EXPORT_SYMBOL_GPL(nvme_wait_freeze);
2382
2383 void nvme_start_freeze(struct nvme_ctrl *ctrl)
2384 {
2385         struct nvme_ns *ns;
2386
2387         mutex_lock(&ctrl->namespaces_mutex);
2388         list_for_each_entry(ns, &ctrl->namespaces, list)
2389                 blk_mq_freeze_queue_start(ns->queue);
2390         mutex_unlock(&ctrl->namespaces_mutex);
2391 }
2392 EXPORT_SYMBOL_GPL(nvme_start_freeze);
2393
2394 void nvme_stop_queues(struct nvme_ctrl *ctrl)
2395 {
2396         struct nvme_ns *ns;
2397
2398         mutex_lock(&ctrl->namespaces_mutex);
2399         list_for_each_entry(ns, &ctrl->namespaces, list)
2400                 blk_mq_quiesce_queue(ns->queue);
2401         mutex_unlock(&ctrl->namespaces_mutex);
2402 }
2403 EXPORT_SYMBOL_GPL(nvme_stop_queues);
2404
2405 void nvme_start_queues(struct nvme_ctrl *ctrl)
2406 {
2407         struct nvme_ns *ns;
2408
2409         mutex_lock(&ctrl->namespaces_mutex);
2410         list_for_each_entry(ns, &ctrl->namespaces, list) {
2411                 blk_mq_start_stopped_hw_queues(ns->queue, true);
2412                 blk_mq_kick_requeue_list(ns->queue);
2413         }
2414         mutex_unlock(&ctrl->namespaces_mutex);
2415 }
2416 EXPORT_SYMBOL_GPL(nvme_start_queues);
2417
2418 int __init nvme_core_init(void)
2419 {
2420         int result;
2421
2422         result = __register_chrdev(nvme_char_major, 0, NVME_MINORS, "nvme",
2423                                                         &nvme_dev_fops);
2424         if (result < 0)
2425                 return result;
2426         else if (result > 0)
2427                 nvme_char_major = result;
2428
2429         nvme_class = class_create(THIS_MODULE, "nvme");
2430         if (IS_ERR(nvme_class)) {
2431                 result = PTR_ERR(nvme_class);
2432                 goto unregister_chrdev;
2433         }
2434
2435         return 0;
2436
2437  unregister_chrdev:
2438         __unregister_chrdev(nvme_char_major, 0, NVME_MINORS, "nvme");
2439         return result;
2440 }
2441
2442 void nvme_core_exit(void)
2443 {
2444         class_destroy(nvme_class);
2445         __unregister_chrdev(nvme_char_major, 0, NVME_MINORS, "nvme");
2446 }
2447
2448 MODULE_LICENSE("GPL");
2449 MODULE_VERSION("1.0");
2450 module_init(nvme_core_init);
2451 module_exit(nvme_core_exit);