whiterose

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core.c (100515B)


      1 // SPDX-License-Identifier: GPL-2.0
      2 /*
      3  * NVM Express device driver
      4  * Copyright (c) 2011-2014, Intel Corporation.
      5  */
      6 
      7 #include <linux/blkdev.h>
      8 #include <linux/blk-mq.h>
      9 #include <linux/delay.h>
     10 #include <linux/errno.h>
     11 #include <linux/hdreg.h>
     12 #include <linux/kernel.h>
     13 #include <linux/module.h>
     14 #include <linux/list_sort.h>
     15 #include <linux/slab.h>
     16 #include <linux/types.h>
     17 #include <linux/pr.h>
     18 #include <linux/ptrace.h>
     19 #include <linux/nvme_ioctl.h>
     20 #include <linux/t10-pi.h>
     21 #include <linux/pm_qos.h>
     22 #include <asm/unaligned.h>
     23 
     24 #define CREATE_TRACE_POINTS
     25 #include "trace.h"
     26 
     27 #include "nvme.h"
     28 #include "fabrics.h"
     29 
     30 #define NVME_MINORS		(1U << MINORBITS)
     31 
     32 unsigned int admin_timeout = 60;
     33 module_param(admin_timeout, uint, 0644);
     34 MODULE_PARM_DESC(admin_timeout, "timeout in seconds for admin commands");
     35 EXPORT_SYMBOL_GPL(admin_timeout);
     36 
     37 unsigned int nvme_io_timeout = 30;
     38 module_param_named(io_timeout, nvme_io_timeout, uint, 0644);
     39 MODULE_PARM_DESC(io_timeout, "timeout in seconds for I/O");
     40 EXPORT_SYMBOL_GPL(nvme_io_timeout);
     41 
     42 static unsigned char shutdown_timeout = 5;
     43 module_param(shutdown_timeout, byte, 0644);
     44 MODULE_PARM_DESC(shutdown_timeout, "timeout in seconds for controller shutdown");
     45 
     46 static u8 nvme_max_retries = 5;
     47 module_param_named(max_retries, nvme_max_retries, byte, 0644);
     48 MODULE_PARM_DESC(max_retries, "max number of retries a command may have");
     49 
     50 static unsigned long default_ps_max_latency_us = 100000;
     51 module_param(default_ps_max_latency_us, ulong, 0644);
     52 MODULE_PARM_DESC(default_ps_max_latency_us,
     53 		 "max power saving latency for new devices; use PM QOS to change per device");
     54 
     55 static bool force_apst;
     56 module_param(force_apst, bool, 0644);
     57 MODULE_PARM_DESC(force_apst, "allow APST for newly enumerated devices even if quirked off");
     58 
     59 static bool streams;
     60 module_param(streams, bool, 0644);
     61 MODULE_PARM_DESC(streams, "turn on support for Streams write directives");
     62 
     63 /*
     64  * nvme_wq - hosts nvme related works that are not reset or delete
     65  * nvme_reset_wq - hosts nvme reset works
     66  * nvme_delete_wq - hosts nvme delete works
     67  *
     68  * nvme_wq will host works such are scan, aen handling, fw activation,
     69  * keep-alive error recovery, periodic reconnects etc. nvme_reset_wq
     70  * runs reset works which also flush works hosted on nvme_wq for
     71  * serialization purposes. nvme_delete_wq host controller deletion
     72  * works which flush reset works for serialization.
     73  */
     74 struct workqueue_struct *nvme_wq;
     75 EXPORT_SYMBOL_GPL(nvme_wq);
     76 
     77 struct workqueue_struct *nvme_reset_wq;
     78 EXPORT_SYMBOL_GPL(nvme_reset_wq);
     79 
     80 struct workqueue_struct *nvme_delete_wq;
     81 EXPORT_SYMBOL_GPL(nvme_delete_wq);
     82 
     83 static DEFINE_IDA(nvme_subsystems_ida);
     84 static LIST_HEAD(nvme_subsystems);
     85 static DEFINE_MUTEX(nvme_subsystems_lock);
     86 
     87 static DEFINE_IDA(nvme_instance_ida);
     88 static dev_t nvme_chr_devt;
     89 static struct class *nvme_class;
     90 static struct class *nvme_subsys_class;
     91 
     92 static int nvme_revalidate_disk(struct gendisk *disk);
     93 static void nvme_put_subsystem(struct nvme_subsystem *subsys);
     94 static void nvme_remove_invalid_namespaces(struct nvme_ctrl *ctrl,
     95 					   unsigned nsid);
     96 
     97 static void nvme_set_queue_dying(struct nvme_ns *ns)
     98 {
     99 	/*
    100 	 * Revalidating a dead namespace sets capacity to 0. This will end
    101 	 * buffered writers dirtying pages that can't be synced.
    102 	 */
    103 	if (!ns->disk || test_and_set_bit(NVME_NS_DEAD, &ns->flags))
    104 		return;
    105 	revalidate_disk(ns->disk);
    106 	blk_set_queue_dying(ns->queue);
    107 	/* Forcibly unquiesce queues to avoid blocking dispatch */
    108 	blk_mq_unquiesce_queue(ns->queue);
    109 }
    110 
    111 static void nvme_queue_scan(struct nvme_ctrl *ctrl)
    112 {
    113 	/*
    114 	 * Only new queue scan work when admin and IO queues are both alive
    115 	 */
    116 	if (ctrl->state == NVME_CTRL_LIVE)
    117 		queue_work(nvme_wq, &ctrl->scan_work);
    118 }
    119 
    120 int nvme_reset_ctrl(struct nvme_ctrl *ctrl)
    121 {
    122 	if (!nvme_change_ctrl_state(ctrl, NVME_CTRL_RESETTING))
    123 		return -EBUSY;
    124 	if (!queue_work(nvme_reset_wq, &ctrl->reset_work))
    125 		return -EBUSY;
    126 	return 0;
    127 }
    128 EXPORT_SYMBOL_GPL(nvme_reset_ctrl);
    129 
    130 int nvme_reset_ctrl_sync(struct nvme_ctrl *ctrl)
    131 {
    132 	int ret;
    133 
    134 	ret = nvme_reset_ctrl(ctrl);
    135 	if (!ret) {
    136 		flush_work(&ctrl->reset_work);
    137 		if (ctrl->state != NVME_CTRL_LIVE &&
    138 		    ctrl->state != NVME_CTRL_ADMIN_ONLY)
    139 			ret = -ENETRESET;
    140 	}
    141 
    142 	return ret;
    143 }
    144 EXPORT_SYMBOL_GPL(nvme_reset_ctrl_sync);
    145 
    146 static void nvme_do_delete_ctrl(struct nvme_ctrl *ctrl)
    147 {
    148 	dev_info(ctrl->device,
    149 		 "Removing ctrl: NQN \"%s\"\n", ctrl->opts->subsysnqn);
    150 
    151 	flush_work(&ctrl->reset_work);
    152 	nvme_stop_ctrl(ctrl);
    153 	nvme_remove_namespaces(ctrl);
    154 	ctrl->ops->delete_ctrl(ctrl);
    155 	nvme_uninit_ctrl(ctrl);
    156 	nvme_put_ctrl(ctrl);
    157 }
    158 
    159 static void nvme_delete_ctrl_work(struct work_struct *work)
    160 {
    161 	struct nvme_ctrl *ctrl =
    162 		container_of(work, struct nvme_ctrl, delete_work);
    163 
    164 	nvme_do_delete_ctrl(ctrl);
    165 }
    166 
    167 int nvme_delete_ctrl(struct nvme_ctrl *ctrl)
    168 {
    169 	if (!nvme_change_ctrl_state(ctrl, NVME_CTRL_DELETING))
    170 		return -EBUSY;
    171 	if (!queue_work(nvme_delete_wq, &ctrl->delete_work))
    172 		return -EBUSY;
    173 	return 0;
    174 }
    175 EXPORT_SYMBOL_GPL(nvme_delete_ctrl);
    176 
    177 static int nvme_delete_ctrl_sync(struct nvme_ctrl *ctrl)
    178 {
    179 	int ret = 0;
    180 
    181 	/*
    182 	 * Keep a reference until nvme_do_delete_ctrl() complete,
    183 	 * since ->delete_ctrl can free the controller.
    184 	 */
    185 	nvme_get_ctrl(ctrl);
    186 	if (!nvme_change_ctrl_state(ctrl, NVME_CTRL_DELETING))
    187 		ret = -EBUSY;
    188 	if (!ret)
    189 		nvme_do_delete_ctrl(ctrl);
    190 	nvme_put_ctrl(ctrl);
    191 	return ret;
    192 }
    193 
    194 static inline bool nvme_ns_has_pi(struct nvme_ns *ns)
    195 {
    196 	return ns->pi_type && ns->ms == sizeof(struct t10_pi_tuple);
    197 }
    198 
    199 static blk_status_t nvme_error_status(struct request *req)
    200 {
    201 	switch (nvme_req(req)->status & 0x7ff) {
    202 	case NVME_SC_SUCCESS:
    203 		return BLK_STS_OK;
    204 	case NVME_SC_CAP_EXCEEDED:
    205 		return BLK_STS_NOSPC;
    206 	case NVME_SC_LBA_RANGE:
    207 		return BLK_STS_TARGET;
    208 	case NVME_SC_BAD_ATTRIBUTES:
    209 	case NVME_SC_ONCS_NOT_SUPPORTED:
    210 	case NVME_SC_INVALID_OPCODE:
    211 	case NVME_SC_INVALID_FIELD:
    212 	case NVME_SC_INVALID_NS:
    213 		return BLK_STS_NOTSUPP;
    214 	case NVME_SC_WRITE_FAULT:
    215 	case NVME_SC_READ_ERROR:
    216 	case NVME_SC_UNWRITTEN_BLOCK:
    217 	case NVME_SC_ACCESS_DENIED:
    218 	case NVME_SC_READ_ONLY:
    219 	case NVME_SC_COMPARE_FAILED:
    220 		return BLK_STS_MEDIUM;
    221 	case NVME_SC_GUARD_CHECK:
    222 	case NVME_SC_APPTAG_CHECK:
    223 	case NVME_SC_REFTAG_CHECK:
    224 	case NVME_SC_INVALID_PI:
    225 		return BLK_STS_PROTECTION;
    226 	case NVME_SC_RESERVATION_CONFLICT:
    227 		return BLK_STS_NEXUS;
    228 	default:
    229 		return BLK_STS_IOERR;
    230 	}
    231 }
    232 
    233 static inline bool nvme_req_needs_retry(struct request *req)
    234 {
    235 	if (blk_noretry_request(req))
    236 		return false;
    237 	if (nvme_req(req)->status & NVME_SC_DNR)
    238 		return false;
    239 	if (nvme_req(req)->retries >= nvme_max_retries)
    240 		return false;
    241 	return true;
    242 }
    243 
    244 static void nvme_retry_req(struct request *req)
    245 {
    246 	struct nvme_ns *ns = req->q->queuedata;
    247 	unsigned long delay = 0;
    248 	u16 crd;
    249 
    250 	/* The mask and shift result must be <= 3 */
    251 	crd = (nvme_req(req)->status & NVME_SC_CRD) >> 11;
    252 	if (ns && crd)
    253 		delay = ns->ctrl->crdt[crd - 1] * 100;
    254 
    255 	nvme_req(req)->retries++;
    256 	blk_mq_requeue_request(req, false);
    257 	blk_mq_delay_kick_requeue_list(req->q, delay);
    258 }
    259 
    260 void nvme_complete_rq(struct request *req)
    261 {
    262 	blk_status_t status = nvme_error_status(req);
    263 
    264 	trace_nvme_complete_rq(req);
    265 
    266 	if (nvme_req(req)->ctrl->kas)
    267 		nvme_req(req)->ctrl->comp_seen = true;
    268 
    269 	if (unlikely(status != BLK_STS_OK && nvme_req_needs_retry(req))) {
    270 		if ((req->cmd_flags & REQ_NVME_MPATH) &&
    271 		    blk_path_error(status)) {
    272 			nvme_failover_req(req);
    273 			return;
    274 		}
    275 
    276 		if (!blk_queue_dying(req->q)) {
    277 			nvme_retry_req(req);
    278 			return;
    279 		}
    280 	}
    281 	blk_mq_end_request(req, status);
    282 }
    283 EXPORT_SYMBOL_GPL(nvme_complete_rq);
    284 
    285 bool nvme_cancel_request(struct request *req, void *data, bool reserved)
    286 {
    287 	dev_dbg_ratelimited(((struct nvme_ctrl *) data)->device,
    288 				"Cancelling I/O %d", req->tag);
    289 
    290 	nvme_req(req)->status = NVME_SC_ABORT_REQ;
    291 	blk_mq_complete_request_sync(req);
    292 	return true;
    293 }
    294 EXPORT_SYMBOL_GPL(nvme_cancel_request);
    295 
    296 bool nvme_change_ctrl_state(struct nvme_ctrl *ctrl,
    297 		enum nvme_ctrl_state new_state)
    298 {
    299 	enum nvme_ctrl_state old_state;
    300 	unsigned long flags;
    301 	bool changed = false;
    302 
    303 	spin_lock_irqsave(&ctrl->lock, flags);
    304 
    305 	old_state = ctrl->state;
    306 	switch (new_state) {
    307 	case NVME_CTRL_ADMIN_ONLY:
    308 		switch (old_state) {
    309 		case NVME_CTRL_CONNECTING:
    310 			changed = true;
    311 			/* FALLTHRU */
    312 		default:
    313 			break;
    314 		}
    315 		break;
    316 	case NVME_CTRL_LIVE:
    317 		switch (old_state) {
    318 		case NVME_CTRL_NEW:
    319 		case NVME_CTRL_RESETTING:
    320 		case NVME_CTRL_CONNECTING:
    321 			changed = true;
    322 			/* FALLTHRU */
    323 		default:
    324 			break;
    325 		}
    326 		break;
    327 	case NVME_CTRL_RESETTING:
    328 		switch (old_state) {
    329 		case NVME_CTRL_NEW:
    330 		case NVME_CTRL_LIVE:
    331 		case NVME_CTRL_ADMIN_ONLY:
    332 			changed = true;
    333 			/* FALLTHRU */
    334 		default:
    335 			break;
    336 		}
    337 		break;
    338 	case NVME_CTRL_CONNECTING:
    339 		switch (old_state) {
    340 		case NVME_CTRL_NEW:
    341 		case NVME_CTRL_RESETTING:
    342 			changed = true;
    343 			/* FALLTHRU */
    344 		default:
    345 			break;
    346 		}
    347 		break;
    348 	case NVME_CTRL_DELETING:
    349 		switch (old_state) {
    350 		case NVME_CTRL_LIVE:
    351 		case NVME_CTRL_ADMIN_ONLY:
    352 		case NVME_CTRL_RESETTING:
    353 		case NVME_CTRL_CONNECTING:
    354 			changed = true;
    355 			/* FALLTHRU */
    356 		default:
    357 			break;
    358 		}
    359 		break;
    360 	case NVME_CTRL_DEAD:
    361 		switch (old_state) {
    362 		case NVME_CTRL_DELETING:
    363 			changed = true;
    364 			/* FALLTHRU */
    365 		default:
    366 			break;
    367 		}
    368 		break;
    369 	default:
    370 		break;
    371 	}
    372 
    373 	if (changed)
    374 		ctrl->state = new_state;
    375 
    376 	spin_unlock_irqrestore(&ctrl->lock, flags);
    377 	if (changed && ctrl->state == NVME_CTRL_LIVE)
    378 		nvme_kick_requeue_lists(ctrl);
    379 	return changed;
    380 }
    381 EXPORT_SYMBOL_GPL(nvme_change_ctrl_state);
    382 
    383 static void nvme_free_ns_head(struct kref *ref)
    384 {
    385 	struct nvme_ns_head *head =
    386 		container_of(ref, struct nvme_ns_head, ref);
    387 
    388 	nvme_mpath_remove_disk(head);
    389 	ida_simple_remove(&head->subsys->ns_ida, head->instance);
    390 	list_del_init(&head->entry);
    391 	cleanup_srcu_struct_quiesced(&head->srcu);
    392 	nvme_put_subsystem(head->subsys);
    393 	kfree(head);
    394 }
    395 
    396 static void nvme_put_ns_head(struct nvme_ns_head *head)
    397 {
    398 	kref_put(&head->ref, nvme_free_ns_head);
    399 }
    400 
    401 static void nvme_free_ns(struct kref *kref)
    402 {
    403 	struct nvme_ns *ns = container_of(kref, struct nvme_ns, kref);
    404 
    405 	if (ns->ndev)
    406 		nvme_nvm_unregister(ns);
    407 
    408 	put_disk(ns->disk);
    409 	nvme_put_ns_head(ns->head);
    410 	nvme_put_ctrl(ns->ctrl);
    411 	kfree(ns);
    412 }
    413 
    414 static void nvme_put_ns(struct nvme_ns *ns)
    415 {
    416 	kref_put(&ns->kref, nvme_free_ns);
    417 }
    418 
    419 static inline void nvme_clear_nvme_request(struct request *req)
    420 {
    421 	if (!(req->rq_flags & RQF_DONTPREP)) {
    422 		nvme_req(req)->retries = 0;
    423 		nvme_req(req)->flags = 0;
    424 		req->rq_flags |= RQF_DONTPREP;
    425 	}
    426 }
    427 
    428 struct request *nvme_alloc_request(struct request_queue *q,
    429 		struct nvme_command *cmd, blk_mq_req_flags_t flags, int qid)
    430 {
    431 	unsigned op = nvme_is_write(cmd) ? REQ_OP_DRV_OUT : REQ_OP_DRV_IN;
    432 	struct request *req;
    433 
    434 	if (qid == NVME_QID_ANY) {
    435 		req = blk_mq_alloc_request(q, op, flags);
    436 	} else {
    437 		req = blk_mq_alloc_request_hctx(q, op, flags,
    438 				qid ? qid - 1 : 0);
    439 	}
    440 	if (IS_ERR(req))
    441 		return req;
    442 
    443 	req->cmd_flags |= REQ_FAILFAST_DRIVER;
    444 	nvme_clear_nvme_request(req);
    445 	nvme_req(req)->cmd = cmd;
    446 
    447 	return req;
    448 }
    449 EXPORT_SYMBOL_GPL(nvme_alloc_request);
    450 
    451 static int nvme_toggle_streams(struct nvme_ctrl *ctrl, bool enable)
    452 {
    453 	struct nvme_command c;
    454 
    455 	memset(&c, 0, sizeof(c));
    456 
    457 	c.directive.opcode = nvme_admin_directive_send;
    458 	c.directive.nsid = cpu_to_le32(NVME_NSID_ALL);
    459 	c.directive.doper = NVME_DIR_SND_ID_OP_ENABLE;
    460 	c.directive.dtype = NVME_DIR_IDENTIFY;
    461 	c.directive.tdtype = NVME_DIR_STREAMS;
    462 	c.directive.endir = enable ? NVME_DIR_ENDIR : 0;
    463 
    464 	return nvme_submit_sync_cmd(ctrl->admin_q, &c, NULL, 0);
    465 }
    466 
    467 static int nvme_disable_streams(struct nvme_ctrl *ctrl)
    468 {
    469 	return nvme_toggle_streams(ctrl, false);
    470 }
    471 
    472 static int nvme_enable_streams(struct nvme_ctrl *ctrl)
    473 {
    474 	return nvme_toggle_streams(ctrl, true);
    475 }
    476 
    477 static int nvme_get_stream_params(struct nvme_ctrl *ctrl,
    478 				  struct streams_directive_params *s, u32 nsid)
    479 {
    480 	struct nvme_command c;
    481 
    482 	memset(&c, 0, sizeof(c));
    483 	memset(s, 0, sizeof(*s));
    484 
    485 	c.directive.opcode = nvme_admin_directive_recv;
    486 	c.directive.nsid = cpu_to_le32(nsid);
    487 	c.directive.numd = cpu_to_le32((sizeof(*s) >> 2) - 1);
    488 	c.directive.doper = NVME_DIR_RCV_ST_OP_PARAM;
    489 	c.directive.dtype = NVME_DIR_STREAMS;
    490 
    491 	return nvme_submit_sync_cmd(ctrl->admin_q, &c, s, sizeof(*s));
    492 }
    493 
    494 static int nvme_configure_directives(struct nvme_ctrl *ctrl)
    495 {
    496 	struct streams_directive_params s;
    497 	int ret;
    498 
    499 	if (!(ctrl->oacs & NVME_CTRL_OACS_DIRECTIVES))
    500 		return 0;
    501 	if (!streams)
    502 		return 0;
    503 
    504 	ret = nvme_enable_streams(ctrl);
    505 	if (ret)
    506 		return ret;
    507 
    508 	ret = nvme_get_stream_params(ctrl, &s, NVME_NSID_ALL);
    509 	if (ret)
    510 		return ret;
    511 
    512 	ctrl->nssa = le16_to_cpu(s.nssa);
    513 	if (ctrl->nssa < BLK_MAX_WRITE_HINTS - 1) {
    514 		dev_info(ctrl->device, "too few streams (%u) available\n",
    515 					ctrl->nssa);
    516 		nvme_disable_streams(ctrl);
    517 		return 0;
    518 	}
    519 
    520 	ctrl->nr_streams = min_t(unsigned, ctrl->nssa, BLK_MAX_WRITE_HINTS - 1);
    521 	dev_info(ctrl->device, "Using %u streams\n", ctrl->nr_streams);
    522 	return 0;
    523 }
    524 
    525 /*
    526  * Check if 'req' has a write hint associated with it. If it does, assign
    527  * a valid namespace stream to the write.
    528  */
    529 static void nvme_assign_write_stream(struct nvme_ctrl *ctrl,
    530 				     struct request *req, u16 *control,
    531 				     u32 *dsmgmt)
    532 {
    533 	enum rw_hint streamid = req->write_hint;
    534 
    535 	if (streamid == WRITE_LIFE_NOT_SET || streamid == WRITE_LIFE_NONE)
    536 		streamid = 0;
    537 	else {
    538 		streamid--;
    539 		if (WARN_ON_ONCE(streamid > ctrl->nr_streams))
    540 			return;
    541 
    542 		*control |= NVME_RW_DTYPE_STREAMS;
    543 		*dsmgmt |= streamid << 16;
    544 	}
    545 
    546 	if (streamid < ARRAY_SIZE(req->q->write_hints))
    547 		req->q->write_hints[streamid] += blk_rq_bytes(req) >> 9;
    548 }
    549 
    550 static inline void nvme_setup_flush(struct nvme_ns *ns,
    551 		struct nvme_command *cmnd)
    552 {
    553 	cmnd->common.opcode = nvme_cmd_flush;
    554 	cmnd->common.nsid = cpu_to_le32(ns->head->ns_id);
    555 }
    556 
    557 static blk_status_t nvme_setup_discard(struct nvme_ns *ns, struct request *req,
    558 		struct nvme_command *cmnd)
    559 {
    560 	unsigned short segments = blk_rq_nr_discard_segments(req), n = 0;
    561 	struct nvme_dsm_range *range;
    562 	struct bio *bio;
    563 
    564 	range = kmalloc_array(segments, sizeof(*range),
    565 				GFP_ATOMIC | __GFP_NOWARN);
    566 	if (!range) {
    567 		/*
    568 		 * If we fail allocation our range, fallback to the controller
    569 		 * discard page. If that's also busy, it's safe to return
    570 		 * busy, as we know we can make progress once that's freed.
    571 		 */
    572 		if (test_and_set_bit_lock(0, &ns->ctrl->discard_page_busy))
    573 			return BLK_STS_RESOURCE;
    574 
    575 		range = page_address(ns->ctrl->discard_page);
    576 	}
    577 
    578 	__rq_for_each_bio(bio, req) {
    579 		u64 slba = nvme_block_nr(ns, bio->bi_iter.bi_sector);
    580 		u32 nlb = bio->bi_iter.bi_size >> ns->lba_shift;
    581 
    582 		if (n < segments) {
    583 			range[n].cattr = cpu_to_le32(0);
    584 			range[n].nlb = cpu_to_le32(nlb);
    585 			range[n].slba = cpu_to_le64(slba);
    586 		}
    587 		n++;
    588 	}
    589 
    590 	if (WARN_ON_ONCE(n != segments)) {
    591 		if (virt_to_page(range) == ns->ctrl->discard_page)
    592 			clear_bit_unlock(0, &ns->ctrl->discard_page_busy);
    593 		else
    594 			kfree(range);
    595 		return BLK_STS_IOERR;
    596 	}
    597 
    598 	cmnd->dsm.opcode = nvme_cmd_dsm;
    599 	cmnd->dsm.nsid = cpu_to_le32(ns->head->ns_id);
    600 	cmnd->dsm.nr = cpu_to_le32(segments - 1);
    601 	cmnd->dsm.attributes = cpu_to_le32(NVME_DSMGMT_AD);
    602 
    603 	req->special_vec.bv_page = virt_to_page(range);
    604 	req->special_vec.bv_offset = offset_in_page(range);
    605 	req->special_vec.bv_len = sizeof(*range) * segments;
    606 	req->rq_flags |= RQF_SPECIAL_PAYLOAD;
    607 
    608 	return BLK_STS_OK;
    609 }
    610 
    611 static inline blk_status_t nvme_setup_write_zeroes(struct nvme_ns *ns,
    612 		struct request *req, struct nvme_command *cmnd)
    613 {
    614 	if (ns->ctrl->quirks & NVME_QUIRK_DEALLOCATE_ZEROES)
    615 		return nvme_setup_discard(ns, req, cmnd);
    616 
    617 	cmnd->write_zeroes.opcode = nvme_cmd_write_zeroes;
    618 	cmnd->write_zeroes.nsid = cpu_to_le32(ns->head->ns_id);
    619 	cmnd->write_zeroes.slba =
    620 		cpu_to_le64(nvme_block_nr(ns, blk_rq_pos(req)));
    621 	cmnd->write_zeroes.length =
    622 		cpu_to_le16((blk_rq_bytes(req) >> ns->lba_shift) - 1);
    623 	cmnd->write_zeroes.control = 0;
    624 	return BLK_STS_OK;
    625 }
    626 
    627 static inline blk_status_t nvme_setup_rw(struct nvme_ns *ns,
    628 		struct request *req, struct nvme_command *cmnd)
    629 {
    630 	struct nvme_ctrl *ctrl = ns->ctrl;
    631 	u16 control = 0;
    632 	u32 dsmgmt = 0;
    633 
    634 	if (req->cmd_flags & REQ_FUA)
    635 		control |= NVME_RW_FUA;
    636 	if (req->cmd_flags & (REQ_FAILFAST_DEV | REQ_RAHEAD))
    637 		control |= NVME_RW_LR;
    638 
    639 	if (req->cmd_flags & REQ_RAHEAD)
    640 		dsmgmt |= NVME_RW_DSM_FREQ_PREFETCH;
    641 
    642 	cmnd->rw.opcode = (rq_data_dir(req) ? nvme_cmd_write : nvme_cmd_read);
    643 	cmnd->rw.nsid = cpu_to_le32(ns->head->ns_id);
    644 	cmnd->rw.slba = cpu_to_le64(nvme_block_nr(ns, blk_rq_pos(req)));
    645 	cmnd->rw.length = cpu_to_le16((blk_rq_bytes(req) >> ns->lba_shift) - 1);
    646 
    647 	if (req_op(req) == REQ_OP_WRITE && ctrl->nr_streams)
    648 		nvme_assign_write_stream(ctrl, req, &control, &dsmgmt);
    649 
    650 	if (ns->ms) {
    651 		/*
    652 		 * If formated with metadata, the block layer always provides a
    653 		 * metadata buffer if CONFIG_BLK_DEV_INTEGRITY is enabled.  Else
    654 		 * we enable the PRACT bit for protection information or set the
    655 		 * namespace capacity to zero to prevent any I/O.
    656 		 */
    657 		if (!blk_integrity_rq(req)) {
    658 			if (WARN_ON_ONCE(!nvme_ns_has_pi(ns)))
    659 				return BLK_STS_NOTSUPP;
    660 			control |= NVME_RW_PRINFO_PRACT;
    661 		} else if (req_op(req) == REQ_OP_WRITE) {
    662 			t10_pi_prepare(req, ns->pi_type);
    663 		}
    664 
    665 		switch (ns->pi_type) {
    666 		case NVME_NS_DPS_PI_TYPE3:
    667 			control |= NVME_RW_PRINFO_PRCHK_GUARD;
    668 			break;
    669 		case NVME_NS_DPS_PI_TYPE1:
    670 		case NVME_NS_DPS_PI_TYPE2:
    671 			control |= NVME_RW_PRINFO_PRCHK_GUARD |
    672 					NVME_RW_PRINFO_PRCHK_REF;
    673 			cmnd->rw.reftag = cpu_to_le32(t10_pi_ref_tag(req));
    674 			break;
    675 		}
    676 	}
    677 
    678 	cmnd->rw.control = cpu_to_le16(control);
    679 	cmnd->rw.dsmgmt = cpu_to_le32(dsmgmt);
    680 	return 0;
    681 }
    682 
    683 void nvme_cleanup_cmd(struct request *req)
    684 {
    685 	if (blk_integrity_rq(req) && req_op(req) == REQ_OP_READ &&
    686 	    nvme_req(req)->status == 0) {
    687 		struct nvme_ns *ns = req->rq_disk->private_data;
    688 
    689 		t10_pi_complete(req, ns->pi_type,
    690 				blk_rq_bytes(req) >> ns->lba_shift);
    691 	}
    692 	if (req->rq_flags & RQF_SPECIAL_PAYLOAD) {
    693 		struct nvme_ns *ns = req->rq_disk->private_data;
    694 		struct page *page = req->special_vec.bv_page;
    695 
    696 		if (page == ns->ctrl->discard_page)
    697 			clear_bit_unlock(0, &ns->ctrl->discard_page_busy);
    698 		else
    699 			kfree(page_address(page) + req->special_vec.bv_offset);
    700 	}
    701 }
    702 EXPORT_SYMBOL_GPL(nvme_cleanup_cmd);
    703 
    704 blk_status_t nvme_setup_cmd(struct nvme_ns *ns, struct request *req,
    705 		struct nvme_command *cmd)
    706 {
    707 	blk_status_t ret = BLK_STS_OK;
    708 
    709 	nvme_clear_nvme_request(req);
    710 
    711 	memset(cmd, 0, sizeof(*cmd));
    712 	switch (req_op(req)) {
    713 	case REQ_OP_DRV_IN:
    714 	case REQ_OP_DRV_OUT:
    715 		memcpy(cmd, nvme_req(req)->cmd, sizeof(*cmd));
    716 		break;
    717 	case REQ_OP_FLUSH:
    718 		nvme_setup_flush(ns, cmd);
    719 		break;
    720 	case REQ_OP_WRITE_ZEROES:
    721 		ret = nvme_setup_write_zeroes(ns, req, cmd);
    722 		break;
    723 	case REQ_OP_DISCARD:
    724 		ret = nvme_setup_discard(ns, req, cmd);
    725 		break;
    726 	case REQ_OP_READ:
    727 	case REQ_OP_WRITE:
    728 		ret = nvme_setup_rw(ns, req, cmd);
    729 		break;
    730 	default:
    731 		WARN_ON_ONCE(1);
    732 		return BLK_STS_IOERR;
    733 	}
    734 
    735 	cmd->common.command_id = req->tag;
    736 	trace_nvme_setup_cmd(req, cmd);
    737 	return ret;
    738 }
    739 EXPORT_SYMBOL_GPL(nvme_setup_cmd);
    740 
    741 static void nvme_end_sync_rq(struct request *rq, blk_status_t error)
    742 {
    743 	struct completion *waiting = rq->end_io_data;
    744 
    745 	rq->end_io_data = NULL;
    746 	complete(waiting);
    747 }
    748 
    749 static void nvme_execute_rq_polled(struct request_queue *q,
    750 		struct gendisk *bd_disk, struct request *rq, int at_head)
    751 {
    752 	DECLARE_COMPLETION_ONSTACK(wait);
    753 
    754 	WARN_ON_ONCE(!test_bit(QUEUE_FLAG_POLL, &q->queue_flags));
    755 
    756 	rq->cmd_flags |= REQ_HIPRI;
    757 	rq->end_io_data = &wait;
    758 	blk_execute_rq_nowait(q, bd_disk, rq, at_head, nvme_end_sync_rq);
    759 
    760 	while (!completion_done(&wait)) {
    761 		blk_poll(q, request_to_qc_t(rq->mq_hctx, rq), true);
    762 		cond_resched();
    763 	}
    764 }
    765 
    766 /*
    767  * Returns 0 on success.  If the result is negative, it's a Linux error code;
    768  * if the result is positive, it's an NVM Express status code
    769  */
    770 int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
    771 		union nvme_result *result, void *buffer, unsigned bufflen,
    772 		unsigned timeout, int qid, int at_head,
    773 		blk_mq_req_flags_t flags, bool poll)
    774 {
    775 	struct request *req;
    776 	int ret;
    777 
    778 	req = nvme_alloc_request(q, cmd, flags, qid);
    779 	if (IS_ERR(req))
    780 		return PTR_ERR(req);
    781 
    782 	req->timeout = timeout ? timeout : ADMIN_TIMEOUT;
    783 
    784 	if (buffer && bufflen) {
    785 		ret = blk_rq_map_kern(q, req, buffer, bufflen, GFP_KERNEL);
    786 		if (ret)
    787 			goto out;
    788 	}
    789 
    790 	if (poll)
    791 		nvme_execute_rq_polled(req->q, NULL, req, at_head);
    792 	else
    793 		blk_execute_rq(req->q, NULL, req, at_head);
    794 	if (result)
    795 		*result = nvme_req(req)->result;
    796 	if (nvme_req(req)->flags & NVME_REQ_CANCELLED)
    797 		ret = -EINTR;
    798 	else
    799 		ret = nvme_req(req)->status;
    800  out:
    801 	blk_mq_free_request(req);
    802 	return ret;
    803 }
    804 EXPORT_SYMBOL_GPL(__nvme_submit_sync_cmd);
    805 
    806 int nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
    807 		void *buffer, unsigned bufflen)
    808 {
    809 	return __nvme_submit_sync_cmd(q, cmd, NULL, buffer, bufflen, 0,
    810 			NVME_QID_ANY, 0, 0, false);
    811 }
    812 EXPORT_SYMBOL_GPL(nvme_submit_sync_cmd);
    813 
    814 static void *nvme_add_user_metadata(struct bio *bio, void __user *ubuf,
    815 		unsigned len, u32 seed, bool write)
    816 {
    817 	struct bio_integrity_payload *bip;
    818 	int ret = -ENOMEM;
    819 	void *buf;
    820 
    821 	buf = kmalloc(len, GFP_KERNEL);
    822 	if (!buf)
    823 		goto out;
    824 
    825 	ret = -EFAULT;
    826 	if (write && copy_from_user(buf, ubuf, len))
    827 		goto out_free_meta;
    828 
    829 	bip = bio_integrity_alloc(bio, GFP_KERNEL, 1);
    830 	if (IS_ERR(bip)) {
    831 		ret = PTR_ERR(bip);
    832 		goto out_free_meta;
    833 	}
    834 
    835 	bip->bip_iter.bi_size = len;
    836 	bip->bip_iter.bi_sector = seed;
    837 	ret = bio_integrity_add_page(bio, virt_to_page(buf), len,
    838 			offset_in_page(buf));
    839 	if (ret == len)
    840 		return buf;
    841 	ret = -ENOMEM;
    842 out_free_meta:
    843 	kfree(buf);
    844 out:
    845 	return ERR_PTR(ret);
    846 }
    847 
    848 static int nvme_submit_user_cmd(struct request_queue *q,
    849 		struct nvme_command *cmd, void __user *ubuffer,
    850 		unsigned bufflen, void __user *meta_buffer, unsigned meta_len,
    851 		u32 meta_seed, u32 *result, unsigned timeout)
    852 {
    853 	bool write = nvme_is_write(cmd);
    854 	struct nvme_ns *ns = q->queuedata;
    855 	struct gendisk *disk = ns ? ns->disk : NULL;
    856 	struct request *req;
    857 	struct bio *bio = NULL;
    858 	void *meta = NULL;
    859 	int ret;
    860 
    861 	req = nvme_alloc_request(q, cmd, 0, NVME_QID_ANY);
    862 	if (IS_ERR(req))
    863 		return PTR_ERR(req);
    864 
    865 	req->timeout = timeout ? timeout : ADMIN_TIMEOUT;
    866 	nvme_req(req)->flags |= NVME_REQ_USERCMD;
    867 
    868 	if (ubuffer && bufflen) {
    869 		ret = blk_rq_map_user(q, req, NULL, ubuffer, bufflen,
    870 				GFP_KERNEL);
    871 		if (ret)
    872 			goto out;
    873 		bio = req->bio;
    874 		bio->bi_disk = disk;
    875 		if (disk && meta_buffer && meta_len) {
    876 			meta = nvme_add_user_metadata(bio, meta_buffer, meta_len,
    877 					meta_seed, write);
    878 			if (IS_ERR(meta)) {
    879 				ret = PTR_ERR(meta);
    880 				goto out_unmap;
    881 			}
    882 			req->cmd_flags |= REQ_INTEGRITY;
    883 		}
    884 	}
    885 
    886 	blk_execute_rq(req->q, disk, req, 0);
    887 	if (nvme_req(req)->flags & NVME_REQ_CANCELLED)
    888 		ret = -EINTR;
    889 	else
    890 		ret = nvme_req(req)->status;
    891 	if (result)
    892 		*result = le32_to_cpu(nvme_req(req)->result.u32);
    893 	if (meta && !ret && !write) {
    894 		if (copy_to_user(meta_buffer, meta, meta_len))
    895 			ret = -EFAULT;
    896 	}
    897 	kfree(meta);
    898  out_unmap:
    899 	if (bio)
    900 		blk_rq_unmap_user(bio);
    901  out:
    902 	blk_mq_free_request(req);
    903 	return ret;
    904 }
    905 
    906 static void nvme_keep_alive_end_io(struct request *rq, blk_status_t status)
    907 {
    908 	struct nvme_ctrl *ctrl = rq->end_io_data;
    909 	unsigned long flags;
    910 	bool startka = false;
    911 
    912 	blk_mq_free_request(rq);
    913 
    914 	if (status) {
    915 		dev_err(ctrl->device,
    916 			"failed nvme_keep_alive_end_io error=%d\n",
    917 				status);
    918 		return;
    919 	}
    920 
    921 	ctrl->comp_seen = false;
    922 	spin_lock_irqsave(&ctrl->lock, flags);
    923 	if (ctrl->state == NVME_CTRL_LIVE ||
    924 	    ctrl->state == NVME_CTRL_CONNECTING)
    925 		startka = true;
    926 	spin_unlock_irqrestore(&ctrl->lock, flags);
    927 	if (startka)
    928 		schedule_delayed_work(&ctrl->ka_work, ctrl->kato * HZ);
    929 }
    930 
    931 static int nvme_keep_alive(struct nvme_ctrl *ctrl)
    932 {
    933 	struct request *rq;
    934 
    935 	rq = nvme_alloc_request(ctrl->admin_q, &ctrl->ka_cmd, BLK_MQ_REQ_RESERVED,
    936 			NVME_QID_ANY);
    937 	if (IS_ERR(rq))
    938 		return PTR_ERR(rq);
    939 
    940 	rq->timeout = ctrl->kato * HZ;
    941 	rq->end_io_data = ctrl;
    942 
    943 	blk_execute_rq_nowait(rq->q, NULL, rq, 0, nvme_keep_alive_end_io);
    944 
    945 	return 0;
    946 }
    947 
    948 static void nvme_keep_alive_work(struct work_struct *work)
    949 {
    950 	struct nvme_ctrl *ctrl = container_of(to_delayed_work(work),
    951 			struct nvme_ctrl, ka_work);
    952 	bool comp_seen = ctrl->comp_seen;
    953 
    954 	if ((ctrl->ctratt & NVME_CTRL_ATTR_TBKAS) && comp_seen) {
    955 		dev_dbg(ctrl->device,
    956 			"reschedule traffic based keep-alive timer\n");
    957 		ctrl->comp_seen = false;
    958 		schedule_delayed_work(&ctrl->ka_work, ctrl->kato * HZ);
    959 		return;
    960 	}
    961 
    962 	if (nvme_keep_alive(ctrl)) {
    963 		/* allocation failure, reset the controller */
    964 		dev_err(ctrl->device, "keep-alive failed\n");
    965 		nvme_reset_ctrl(ctrl);
    966 		return;
    967 	}
    968 }
    969 
    970 static void nvme_start_keep_alive(struct nvme_ctrl *ctrl)
    971 {
    972 	if (unlikely(ctrl->kato == 0))
    973 		return;
    974 
    975 	schedule_delayed_work(&ctrl->ka_work, ctrl->kato * HZ);
    976 }
    977 
    978 void nvme_stop_keep_alive(struct nvme_ctrl *ctrl)
    979 {
    980 	if (unlikely(ctrl->kato == 0))
    981 		return;
    982 
    983 	cancel_delayed_work_sync(&ctrl->ka_work);
    984 }
    985 EXPORT_SYMBOL_GPL(nvme_stop_keep_alive);
    986 
    987 static int nvme_identify_ctrl(struct nvme_ctrl *dev, struct nvme_id_ctrl **id)
    988 {
    989 	struct nvme_command c = { };
    990 	int error;
    991 
    992 	/* gcc-4.4.4 (at least) has issues with initializers and anon unions */
    993 	c.identify.opcode = nvme_admin_identify;
    994 	c.identify.cns = NVME_ID_CNS_CTRL;
    995 
    996 	*id = kmalloc(sizeof(struct nvme_id_ctrl), GFP_KERNEL);
    997 	if (!*id)
    998 		return -ENOMEM;
    999 
   1000 	error = nvme_submit_sync_cmd(dev->admin_q, &c, *id,
   1001 			sizeof(struct nvme_id_ctrl));
   1002 	if (error)
   1003 		kfree(*id);
   1004 	return error;
   1005 }
   1006 
   1007 static int nvme_identify_ns_descs(struct nvme_ctrl *ctrl, unsigned nsid,
   1008 		struct nvme_ns_ids *ids)
   1009 {
   1010 	struct nvme_command c = { };
   1011 	int status;
   1012 	void *data;
   1013 	int pos;
   1014 	int len;
   1015 
   1016 	c.identify.opcode = nvme_admin_identify;
   1017 	c.identify.nsid = cpu_to_le32(nsid);
   1018 	c.identify.cns = NVME_ID_CNS_NS_DESC_LIST;
   1019 
   1020 	data = kzalloc(NVME_IDENTIFY_DATA_SIZE, GFP_KERNEL);
   1021 	if (!data)
   1022 		return -ENOMEM;
   1023 
   1024 	status = nvme_submit_sync_cmd(ctrl->admin_q, &c, data,
   1025 				      NVME_IDENTIFY_DATA_SIZE);
   1026 	if (status)
   1027 		goto free_data;
   1028 
   1029 	for (pos = 0; pos < NVME_IDENTIFY_DATA_SIZE; pos += len) {
   1030 		struct nvme_ns_id_desc *cur = data + pos;
   1031 
   1032 		if (cur->nidl == 0)
   1033 			break;
   1034 
   1035 		switch (cur->nidt) {
   1036 		case NVME_NIDT_EUI64:
   1037 			if (cur->nidl != NVME_NIDT_EUI64_LEN) {
   1038 				dev_warn(ctrl->device,
   1039 					 "ctrl returned bogus length: %d for NVME_NIDT_EUI64\n",
   1040 					 cur->nidl);
   1041 				goto free_data;
   1042 			}
   1043 			len = NVME_NIDT_EUI64_LEN;
   1044 			memcpy(ids->eui64, data + pos + sizeof(*cur), len);
   1045 			break;
   1046 		case NVME_NIDT_NGUID:
   1047 			if (cur->nidl != NVME_NIDT_NGUID_LEN) {
   1048 				dev_warn(ctrl->device,
   1049 					 "ctrl returned bogus length: %d for NVME_NIDT_NGUID\n",
   1050 					 cur->nidl);
   1051 				goto free_data;
   1052 			}
   1053 			len = NVME_NIDT_NGUID_LEN;
   1054 			memcpy(ids->nguid, data + pos + sizeof(*cur), len);
   1055 			break;
   1056 		case NVME_NIDT_UUID:
   1057 			if (cur->nidl != NVME_NIDT_UUID_LEN) {
   1058 				dev_warn(ctrl->device,
   1059 					 "ctrl returned bogus length: %d for NVME_NIDT_UUID\n",
   1060 					 cur->nidl);
   1061 				goto free_data;
   1062 			}
   1063 			len = NVME_NIDT_UUID_LEN;
   1064 			uuid_copy(&ids->uuid, data + pos + sizeof(*cur));
   1065 			break;
   1066 		default:
   1067 			/* Skip unknown types */
   1068 			len = cur->nidl;
   1069 			break;
   1070 		}
   1071 
   1072 		len += sizeof(*cur);
   1073 	}
   1074 free_data:
   1075 	kfree(data);
   1076 	return status;
   1077 }
   1078 
   1079 static int nvme_identify_ns_list(struct nvme_ctrl *dev, unsigned nsid, __le32 *ns_list)
   1080 {
   1081 	struct nvme_command c = { };
   1082 
   1083 	c.identify.opcode = nvme_admin_identify;
   1084 	c.identify.cns = NVME_ID_CNS_NS_ACTIVE_LIST;
   1085 	c.identify.nsid = cpu_to_le32(nsid);
   1086 	return nvme_submit_sync_cmd(dev->admin_q, &c, ns_list,
   1087 				    NVME_IDENTIFY_DATA_SIZE);
   1088 }
   1089 
   1090 static struct nvme_id_ns *nvme_identify_ns(struct nvme_ctrl *ctrl,
   1091 		unsigned nsid)
   1092 {
   1093 	struct nvme_id_ns *id;
   1094 	struct nvme_command c = { };
   1095 	int error;
   1096 
   1097 	/* gcc-4.4.4 (at least) has issues with initializers and anon unions */
   1098 	c.identify.opcode = nvme_admin_identify;
   1099 	c.identify.nsid = cpu_to_le32(nsid);
   1100 	c.identify.cns = NVME_ID_CNS_NS;
   1101 
   1102 	id = kmalloc(sizeof(*id), GFP_KERNEL);
   1103 	if (!id)
   1104 		return NULL;
   1105 
   1106 	error = nvme_submit_sync_cmd(ctrl->admin_q, &c, id, sizeof(*id));
   1107 	if (error) {
   1108 		dev_warn(ctrl->device, "Identify namespace failed\n");
   1109 		kfree(id);
   1110 		return NULL;
   1111 	}
   1112 
   1113 	return id;
   1114 }
   1115 
   1116 static int nvme_set_features(struct nvme_ctrl *dev, unsigned fid, unsigned dword11,
   1117 		      void *buffer, size_t buflen, u32 *result)
   1118 {
   1119 	struct nvme_command c;
   1120 	union nvme_result res;
   1121 	int ret;
   1122 
   1123 	memset(&c, 0, sizeof(c));
   1124 	c.features.opcode = nvme_admin_set_features;
   1125 	c.features.fid = cpu_to_le32(fid);
   1126 	c.features.dword11 = cpu_to_le32(dword11);
   1127 
   1128 	ret = __nvme_submit_sync_cmd(dev->admin_q, &c, &res,
   1129 			buffer, buflen, 0, NVME_QID_ANY, 0, 0, false);
   1130 	if (ret >= 0 && result)
   1131 		*result = le32_to_cpu(res.u32);
   1132 	return ret;
   1133 }
   1134 
   1135 int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count)
   1136 {
   1137 	u32 q_count = (*count - 1) | ((*count - 1) << 16);
   1138 	u32 result;
   1139 	int status, nr_io_queues;
   1140 
   1141 	status = nvme_set_features(ctrl, NVME_FEAT_NUM_QUEUES, q_count, NULL, 0,
   1142 			&result);
   1143 	if (status < 0)
   1144 		return status;
   1145 
   1146 	/*
   1147 	 * Degraded controllers might return an error when setting the queue
   1148 	 * count.  We still want to be able to bring them online and offer
   1149 	 * access to the admin queue, as that might be only way to fix them up.
   1150 	 */
   1151 	if (status > 0) {
   1152 		dev_err(ctrl->device, "Could not set queue count (%d)\n", status);
   1153 		*count = 0;
   1154 	} else {
   1155 		nr_io_queues = min(result & 0xffff, result >> 16) + 1;
   1156 		*count = min(*count, nr_io_queues);
   1157 	}
   1158 
   1159 	return 0;
   1160 }
   1161 EXPORT_SYMBOL_GPL(nvme_set_queue_count);
   1162 
   1163 #define NVME_AEN_SUPPORTED \
   1164 	(NVME_AEN_CFG_NS_ATTR | NVME_AEN_CFG_FW_ACT | NVME_AEN_CFG_ANA_CHANGE)
   1165 
   1166 static void nvme_enable_aen(struct nvme_ctrl *ctrl)
   1167 {
   1168 	u32 result, supported_aens = ctrl->oaes & NVME_AEN_SUPPORTED;
   1169 	int status;
   1170 
   1171 	if (!supported_aens)
   1172 		return;
   1173 
   1174 	status = nvme_set_features(ctrl, NVME_FEAT_ASYNC_EVENT, supported_aens,
   1175 			NULL, 0, &result);
   1176 	if (status)
   1177 		dev_warn(ctrl->device, "Failed to configure AEN (cfg %x)\n",
   1178 			 supported_aens);
   1179 }
   1180 
   1181 static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio)
   1182 {
   1183 	struct nvme_user_io io;
   1184 	struct nvme_command c;
   1185 	unsigned length, meta_len;
   1186 	void __user *metadata;
   1187 
   1188 	if (copy_from_user(&io, uio, sizeof(io)))
   1189 		return -EFAULT;
   1190 	if (io.flags)
   1191 		return -EINVAL;
   1192 
   1193 	switch (io.opcode) {
   1194 	case nvme_cmd_write:
   1195 	case nvme_cmd_read:
   1196 	case nvme_cmd_compare:
   1197 		break;
   1198 	default:
   1199 		return -EINVAL;
   1200 	}
   1201 
   1202 	length = (io.nblocks + 1) << ns->lba_shift;
   1203 	meta_len = (io.nblocks + 1) * ns->ms;
   1204 	metadata = (void __user *)(uintptr_t)io.metadata;
   1205 
   1206 	if (ns->ext) {
   1207 		length += meta_len;
   1208 		meta_len = 0;
   1209 	} else if (meta_len) {
   1210 		if ((io.metadata & 3) || !io.metadata)
   1211 			return -EINVAL;
   1212 	}
   1213 
   1214 	memset(&c, 0, sizeof(c));
   1215 	c.rw.opcode = io.opcode;
   1216 	c.rw.flags = io.flags;
   1217 	c.rw.nsid = cpu_to_le32(ns->head->ns_id);
   1218 	c.rw.slba = cpu_to_le64(io.slba);
   1219 	c.rw.length = cpu_to_le16(io.nblocks);
   1220 	c.rw.control = cpu_to_le16(io.control);
   1221 	c.rw.dsmgmt = cpu_to_le32(io.dsmgmt);
   1222 	c.rw.reftag = cpu_to_le32(io.reftag);
   1223 	c.rw.apptag = cpu_to_le16(io.apptag);
   1224 	c.rw.appmask = cpu_to_le16(io.appmask);
   1225 
   1226 	return nvme_submit_user_cmd(ns->queue, &c,
   1227 			(void __user *)(uintptr_t)io.addr, length,
   1228 			metadata, meta_len, lower_32_bits(io.slba), NULL, 0);
   1229 }
   1230 
   1231 static u32 nvme_known_admin_effects(u8 opcode)
   1232 {
   1233 	switch (opcode) {
   1234 	case nvme_admin_format_nvm:
   1235 		return NVME_CMD_EFFECTS_CSUPP | NVME_CMD_EFFECTS_LBCC |
   1236 					NVME_CMD_EFFECTS_CSE_MASK;
   1237 	case nvme_admin_sanitize_nvm:
   1238 		return NVME_CMD_EFFECTS_CSE_MASK;
   1239 	default:
   1240 		break;
   1241 	}
   1242 	return 0;
   1243 }
   1244 
   1245 static u32 nvme_passthru_start(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
   1246 								u8 opcode)
   1247 {
   1248 	u32 effects = 0;
   1249 
   1250 	if (ns) {
   1251 		if (ctrl->effects)
   1252 			effects = le32_to_cpu(ctrl->effects->iocs[opcode]);
   1253 		if (effects & ~(NVME_CMD_EFFECTS_CSUPP | NVME_CMD_EFFECTS_LBCC))
   1254 			dev_warn(ctrl->device,
   1255 				 "IO command:%02x has unhandled effects:%08x\n",
   1256 				 opcode, effects);
   1257 		return 0;
   1258 	}
   1259 
   1260 	if (ctrl->effects)
   1261 		effects = le32_to_cpu(ctrl->effects->acs[opcode]);
   1262 	else
   1263 		effects = nvme_known_admin_effects(opcode);
   1264 
   1265 	/*
   1266 	 * For simplicity, IO to all namespaces is quiesced even if the command
   1267 	 * effects say only one namespace is affected.
   1268 	 */
   1269 	if (effects & (NVME_CMD_EFFECTS_LBCC | NVME_CMD_EFFECTS_CSE_MASK)) {
   1270 		mutex_lock(&ctrl->scan_lock);
   1271 		nvme_start_freeze(ctrl);
   1272 		nvme_wait_freeze(ctrl);
   1273 	}
   1274 	return effects;
   1275 }
   1276 
   1277 static void nvme_update_formats(struct nvme_ctrl *ctrl)
   1278 {
   1279 	struct nvme_ns *ns;
   1280 
   1281 	down_read(&ctrl->namespaces_rwsem);
   1282 	list_for_each_entry(ns, &ctrl->namespaces, list)
   1283 		if (ns->disk && nvme_revalidate_disk(ns->disk))
   1284 			nvme_set_queue_dying(ns);
   1285 	up_read(&ctrl->namespaces_rwsem);
   1286 
   1287 	nvme_remove_invalid_namespaces(ctrl, NVME_NSID_ALL);
   1288 }
   1289 
   1290 static void nvme_passthru_end(struct nvme_ctrl *ctrl, u32 effects)
   1291 {
   1292 	/*
   1293 	 * Revalidate LBA changes prior to unfreezing. This is necessary to
   1294 	 * prevent memory corruption if a logical block size was changed by
   1295 	 * this command.
   1296 	 */
   1297 	if (effects & NVME_CMD_EFFECTS_LBCC)
   1298 		nvme_update_formats(ctrl);
   1299 	if (effects & (NVME_CMD_EFFECTS_LBCC | NVME_CMD_EFFECTS_CSE_MASK)) {
   1300 		nvme_unfreeze(ctrl);
   1301 		mutex_unlock(&ctrl->scan_lock);
   1302 	}
   1303 	if (effects & NVME_CMD_EFFECTS_CCC)
   1304 		nvme_init_identify(ctrl);
   1305 	if (effects & (NVME_CMD_EFFECTS_NIC | NVME_CMD_EFFECTS_NCC))
   1306 		nvme_queue_scan(ctrl);
   1307 }
   1308 
   1309 static int nvme_user_cmd(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
   1310 			struct nvme_passthru_cmd __user *ucmd)
   1311 {
   1312 	struct nvme_passthru_cmd cmd;
   1313 	struct nvme_command c;
   1314 	unsigned timeout = 0;
   1315 	u32 effects;
   1316 	int status;
   1317 
   1318 	if (!capable(CAP_SYS_ADMIN))
   1319 		return -EACCES;
   1320 	if (copy_from_user(&cmd, ucmd, sizeof(cmd)))
   1321 		return -EFAULT;
   1322 	if (cmd.flags)
   1323 		return -EINVAL;
   1324 
   1325 	memset(&c, 0, sizeof(c));
   1326 	c.common.opcode = cmd.opcode;
   1327 	c.common.flags = cmd.flags;
   1328 	c.common.nsid = cpu_to_le32(cmd.nsid);
   1329 	c.common.cdw2[0] = cpu_to_le32(cmd.cdw2);
   1330 	c.common.cdw2[1] = cpu_to_le32(cmd.cdw3);
   1331 	c.common.cdw10 = cpu_to_le32(cmd.cdw10);
   1332 	c.common.cdw11 = cpu_to_le32(cmd.cdw11);
   1333 	c.common.cdw12 = cpu_to_le32(cmd.cdw12);
   1334 	c.common.cdw13 = cpu_to_le32(cmd.cdw13);
   1335 	c.common.cdw14 = cpu_to_le32(cmd.cdw14);
   1336 	c.common.cdw15 = cpu_to_le32(cmd.cdw15);
   1337 
   1338 	if (cmd.timeout_ms)
   1339 		timeout = msecs_to_jiffies(cmd.timeout_ms);
   1340 
   1341 	effects = nvme_passthru_start(ctrl, ns, cmd.opcode);
   1342 	status = nvme_submit_user_cmd(ns ? ns->queue : ctrl->admin_q, &c,
   1343 			(void __user *)(uintptr_t)cmd.addr, cmd.data_len,
   1344 			(void __user *)(uintptr_t)cmd.metadata, cmd.metadata_len,
   1345 			0, &cmd.result, timeout);
   1346 	nvme_passthru_end(ctrl, effects);
   1347 
   1348 	if (status >= 0) {
   1349 		if (put_user(cmd.result, &ucmd->result))
   1350 			return -EFAULT;
   1351 	}
   1352 
   1353 	return status;
   1354 }
   1355 
   1356 /*
   1357  * Issue ioctl requests on the first available path.  Note that unlike normal
   1358  * block layer requests we will not retry failed request on another controller.
   1359  */
   1360 static struct nvme_ns *nvme_get_ns_from_disk(struct gendisk *disk,
   1361 		struct nvme_ns_head **head, int *srcu_idx)
   1362 {
   1363 #ifdef CONFIG_NVME_MULTIPATH
   1364 	if (disk->fops == &nvme_ns_head_ops) {
   1365 		*head = disk->private_data;
   1366 		*srcu_idx = srcu_read_lock(&(*head)->srcu);
   1367 		return nvme_find_path(*head);
   1368 	}
   1369 #endif
   1370 	*head = NULL;
   1371 	*srcu_idx = -1;
   1372 	return disk->private_data;
   1373 }
   1374 
   1375 static void nvme_put_ns_from_disk(struct nvme_ns_head *head, int idx)
   1376 {
   1377 	if (head)
   1378 		srcu_read_unlock(&head->srcu, idx);
   1379 }
   1380 
   1381 static int nvme_ns_ioctl(struct nvme_ns *ns, unsigned cmd, unsigned long arg)
   1382 {
   1383 	switch (cmd) {
   1384 	case NVME_IOCTL_ID:
   1385 		force_successful_syscall_return();
   1386 		return ns->head->ns_id;
   1387 	case NVME_IOCTL_ADMIN_CMD:
   1388 		return nvme_user_cmd(ns->ctrl, NULL, (void __user *)arg);
   1389 	case NVME_IOCTL_IO_CMD:
   1390 		return nvme_user_cmd(ns->ctrl, ns, (void __user *)arg);
   1391 	case NVME_IOCTL_SUBMIT_IO:
   1392 		return nvme_submit_io(ns, (void __user *)arg);
   1393 	default:
   1394 #ifdef CONFIG_NVM
   1395 		if (ns->ndev)
   1396 			return nvme_nvm_ioctl(ns, cmd, arg);
   1397 #endif
   1398 		if (is_sed_ioctl(cmd))
   1399 			return sed_ioctl(ns->ctrl->opal_dev, cmd,
   1400 					 (void __user *) arg);
   1401 		return -ENOTTY;
   1402 	}
   1403 }
   1404 
   1405 static int nvme_ioctl(struct block_device *bdev, fmode_t mode,
   1406 		unsigned int cmd, unsigned long arg)
   1407 {
   1408 	struct nvme_ns_head *head = NULL;
   1409 	struct nvme_ns *ns;
   1410 	int srcu_idx, ret;
   1411 
   1412 	ns = nvme_get_ns_from_disk(bdev->bd_disk, &head, &srcu_idx);
   1413 	if (unlikely(!ns))
   1414 		ret = -EWOULDBLOCK;
   1415 	else
   1416 		ret = nvme_ns_ioctl(ns, cmd, arg);
   1417 	nvme_put_ns_from_disk(head, srcu_idx);
   1418 	return ret;
   1419 }
   1420 
   1421 static int nvme_open(struct block_device *bdev, fmode_t mode)
   1422 {
   1423 	struct nvme_ns *ns = bdev->bd_disk->private_data;
   1424 
   1425 #ifdef CONFIG_NVME_MULTIPATH
   1426 	/* should never be called due to GENHD_FL_HIDDEN */
   1427 	if (WARN_ON_ONCE(ns->head->disk))
   1428 		goto fail;
   1429 #endif
   1430 	if (!kref_get_unless_zero(&ns->kref))
   1431 		goto fail;
   1432 	if (!try_module_get(ns->ctrl->ops->module))
   1433 		goto fail_put_ns;
   1434 
   1435 	return 0;
   1436 
   1437 fail_put_ns:
   1438 	nvme_put_ns(ns);
   1439 fail:
   1440 	return -ENXIO;
   1441 }
   1442 
   1443 static void nvme_release(struct gendisk *disk, fmode_t mode)
   1444 {
   1445 	struct nvme_ns *ns = disk->private_data;
   1446 
   1447 	module_put(ns->ctrl->ops->module);
   1448 	nvme_put_ns(ns);
   1449 }
   1450 
   1451 static int nvme_getgeo(struct block_device *bdev, struct hd_geometry *geo)
   1452 {
   1453 	/* some standard values */
   1454 	geo->heads = 1 << 6;
   1455 	geo->sectors = 1 << 5;
   1456 	geo->cylinders = get_capacity(bdev->bd_disk) >> 11;
   1457 	return 0;
   1458 }
   1459 
   1460 #ifdef CONFIG_BLK_DEV_INTEGRITY
   1461 static void nvme_init_integrity(struct gendisk *disk, u16 ms, u8 pi_type)
   1462 {
   1463 	struct blk_integrity integrity;
   1464 
   1465 	memset(&integrity, 0, sizeof(integrity));
   1466 	switch (pi_type) {
   1467 	case NVME_NS_DPS_PI_TYPE3:
   1468 		integrity.profile = &t10_pi_type3_crc;
   1469 		integrity.tag_size = sizeof(u16) + sizeof(u32);
   1470 		integrity.flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
   1471 		break;
   1472 	case NVME_NS_DPS_PI_TYPE1:
   1473 	case NVME_NS_DPS_PI_TYPE2:
   1474 		integrity.profile = &t10_pi_type1_crc;
   1475 		integrity.tag_size = sizeof(u16);
   1476 		integrity.flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
   1477 		break;
   1478 	default:
   1479 		integrity.profile = NULL;
   1480 		break;
   1481 	}
   1482 	integrity.tuple_size = ms;
   1483 	blk_integrity_register(disk, &integrity);
   1484 	blk_queue_max_integrity_segments(disk->queue, 1);
   1485 }
   1486 #else
   1487 static void nvme_init_integrity(struct gendisk *disk, u16 ms, u8 pi_type)
   1488 {
   1489 }
   1490 #endif /* CONFIG_BLK_DEV_INTEGRITY */
   1491 
   1492 static void nvme_set_chunk_size(struct nvme_ns *ns)
   1493 {
   1494 	u32 chunk_size = (((u32)ns->noiob) << (ns->lba_shift - 9));
   1495 	blk_queue_chunk_sectors(ns->queue, rounddown_pow_of_two(chunk_size));
   1496 }
   1497 
   1498 static void nvme_config_discard(struct gendisk *disk, struct nvme_ns *ns)
   1499 {
   1500 	struct nvme_ctrl *ctrl = ns->ctrl;
   1501 	struct request_queue *queue = disk->queue;
   1502 	u32 size = queue_logical_block_size(queue);
   1503 
   1504 	if (!(ctrl->oncs & NVME_CTRL_ONCS_DSM)) {
   1505 		blk_queue_flag_clear(QUEUE_FLAG_DISCARD, queue);
   1506 		return;
   1507 	}
   1508 
   1509 	if (ctrl->nr_streams && ns->sws && ns->sgs)
   1510 		size *= ns->sws * ns->sgs;
   1511 
   1512 	BUILD_BUG_ON(PAGE_SIZE / sizeof(struct nvme_dsm_range) <
   1513 			NVME_DSM_MAX_RANGES);
   1514 
   1515 	queue->limits.discard_alignment = 0;
   1516 	queue->limits.discard_granularity = size;
   1517 
   1518 	/* If discard is already enabled, don't reset queue limits */
   1519 	if (blk_queue_flag_test_and_set(QUEUE_FLAG_DISCARD, queue))
   1520 		return;
   1521 
   1522 	blk_queue_max_discard_sectors(queue, UINT_MAX);
   1523 	blk_queue_max_discard_segments(queue, NVME_DSM_MAX_RANGES);
   1524 
   1525 	if (ctrl->quirks & NVME_QUIRK_DEALLOCATE_ZEROES)
   1526 		blk_queue_max_write_zeroes_sectors(queue, UINT_MAX);
   1527 }
   1528 
   1529 static void nvme_config_write_zeroes(struct gendisk *disk, struct nvme_ns *ns)
   1530 {
   1531 	u32 max_sectors;
   1532 	unsigned short bs = 1 << ns->lba_shift;
   1533 
   1534 	if (!(ns->ctrl->oncs & NVME_CTRL_ONCS_WRITE_ZEROES) ||
   1535 	    (ns->ctrl->quirks & NVME_QUIRK_DISABLE_WRITE_ZEROES))
   1536 		return;
   1537 	/*
   1538 	 * Even though NVMe spec explicitly states that MDTS is not
   1539 	 * applicable to the write-zeroes:- "The restriction does not apply to
   1540 	 * commands that do not transfer data between the host and the
   1541 	 * controller (e.g., Write Uncorrectable ro Write Zeroes command).".
   1542 	 * In order to be more cautious use controller's max_hw_sectors value
   1543 	 * to configure the maximum sectors for the write-zeroes which is
   1544 	 * configured based on the controller's MDTS field in the
   1545 	 * nvme_init_identify() if available.
   1546 	 */
   1547 	if (ns->ctrl->max_hw_sectors == UINT_MAX)
   1548 		max_sectors = ((u32)(USHRT_MAX + 1) * bs) >> 9;
   1549 	else
   1550 		max_sectors = ((u32)(ns->ctrl->max_hw_sectors + 1) * bs) >> 9;
   1551 
   1552 	blk_queue_max_write_zeroes_sectors(disk->queue, max_sectors);
   1553 }
   1554 
   1555 static void nvme_report_ns_ids(struct nvme_ctrl *ctrl, unsigned int nsid,
   1556 		struct nvme_id_ns *id, struct nvme_ns_ids *ids)
   1557 {
   1558 	memset(ids, 0, sizeof(*ids));
   1559 
   1560 	if (ctrl->vs >= NVME_VS(1, 1, 0))
   1561 		memcpy(ids->eui64, id->eui64, sizeof(id->eui64));
   1562 	if (ctrl->vs >= NVME_VS(1, 2, 0))
   1563 		memcpy(ids->nguid, id->nguid, sizeof(id->nguid));
   1564 	if (ctrl->vs >= NVME_VS(1, 3, 0)) {
   1565 		 /* Don't treat error as fatal we potentially
   1566 		  * already have a NGUID or EUI-64
   1567 		  */
   1568 		if (nvme_identify_ns_descs(ctrl, nsid, ids))
   1569 			dev_warn(ctrl->device,
   1570 				 "%s: Identify Descriptors failed\n", __func__);
   1571 	}
   1572 }
   1573 
   1574 static bool nvme_ns_ids_valid(struct nvme_ns_ids *ids)
   1575 {
   1576 	return !uuid_is_null(&ids->uuid) ||
   1577 		memchr_inv(ids->nguid, 0, sizeof(ids->nguid)) ||
   1578 		memchr_inv(ids->eui64, 0, sizeof(ids->eui64));
   1579 }
   1580 
   1581 static bool nvme_ns_ids_equal(struct nvme_ns_ids *a, struct nvme_ns_ids *b)
   1582 {
   1583 	return uuid_equal(&a->uuid, &b->uuid) &&
   1584 		memcmp(&a->nguid, &b->nguid, sizeof(a->nguid)) == 0 &&
   1585 		memcmp(&a->eui64, &b->eui64, sizeof(a->eui64)) == 0;
   1586 }
   1587 
   1588 static void nvme_update_disk_info(struct gendisk *disk,
   1589 		struct nvme_ns *ns, struct nvme_id_ns *id)
   1590 {
   1591 	sector_t capacity = le64_to_cpup(&id->nsze) << (ns->lba_shift - 9);
   1592 	unsigned short bs = 1 << ns->lba_shift;
   1593 
   1594 	blk_mq_freeze_queue(disk->queue);
   1595 	blk_integrity_unregister(disk);
   1596 
   1597 	blk_queue_logical_block_size(disk->queue, bs);
   1598 	blk_queue_physical_block_size(disk->queue, bs);
   1599 	blk_queue_io_min(disk->queue, bs);
   1600 
   1601 	if (ns->ms && !ns->ext &&
   1602 	    (ns->ctrl->ops->flags & NVME_F_METADATA_SUPPORTED))
   1603 		nvme_init_integrity(disk, ns->ms, ns->pi_type);
   1604 	if (ns->ms && !nvme_ns_has_pi(ns) && !blk_get_integrity(disk))
   1605 		capacity = 0;
   1606 
   1607 	set_capacity(disk, capacity);
   1608 
   1609 	nvme_config_discard(disk, ns);
   1610 	nvme_config_write_zeroes(disk, ns);
   1611 
   1612 	if (id->nsattr & (1 << 0))
   1613 		set_disk_ro(disk, true);
   1614 	else
   1615 		set_disk_ro(disk, false);
   1616 
   1617 	blk_mq_unfreeze_queue(disk->queue);
   1618 }
   1619 
   1620 static void __nvme_revalidate_disk(struct gendisk *disk, struct nvme_id_ns *id)
   1621 {
   1622 	struct nvme_ns *ns = disk->private_data;
   1623 
   1624 	/*
   1625 	 * If identify namespace failed, use default 512 byte block size so
   1626 	 * block layer can use before failing read/write for 0 capacity.
   1627 	 */
   1628 	ns->lba_shift = id->lbaf[id->flbas & NVME_NS_FLBAS_LBA_MASK].ds;
   1629 	if (ns->lba_shift == 0)
   1630 		ns->lba_shift = 9;
   1631 	ns->noiob = le16_to_cpu(id->noiob);
   1632 	ns->ms = le16_to_cpu(id->lbaf[id->flbas & NVME_NS_FLBAS_LBA_MASK].ms);
   1633 	ns->ext = ns->ms && (id->flbas & NVME_NS_FLBAS_META_EXT);
   1634 	/* the PI implementation requires metadata equal t10 pi tuple size */
   1635 	if (ns->ms == sizeof(struct t10_pi_tuple))
   1636 		ns->pi_type = id->dps & NVME_NS_DPS_PI_MASK;
   1637 	else
   1638 		ns->pi_type = 0;
   1639 
   1640 	if (ns->noiob)
   1641 		nvme_set_chunk_size(ns);
   1642 	nvme_update_disk_info(disk, ns, id);
   1643 #ifdef CONFIG_NVME_MULTIPATH
   1644 	if (ns->head->disk) {
   1645 		nvme_update_disk_info(ns->head->disk, ns, id);
   1646 		blk_queue_stack_limits(ns->head->disk->queue, ns->queue);
   1647 	}
   1648 #endif
   1649 }
   1650 
   1651 static int nvme_revalidate_disk(struct gendisk *disk)
   1652 {
   1653 	struct nvme_ns *ns = disk->private_data;
   1654 	struct nvme_ctrl *ctrl = ns->ctrl;
   1655 	struct nvme_id_ns *id;
   1656 	struct nvme_ns_ids ids;
   1657 	int ret = 0;
   1658 
   1659 	if (test_bit(NVME_NS_DEAD, &ns->flags)) {
   1660 		set_capacity(disk, 0);
   1661 		return -ENODEV;
   1662 	}
   1663 
   1664 	id = nvme_identify_ns(ctrl, ns->head->ns_id);
   1665 	if (!id)
   1666 		return -ENODEV;
   1667 
   1668 	if (id->ncap == 0) {
   1669 		ret = -ENODEV;
   1670 		goto out;
   1671 	}
   1672 
   1673 	__nvme_revalidate_disk(disk, id);
   1674 	nvme_report_ns_ids(ctrl, ns->head->ns_id, id, &ids);
   1675 	if (!nvme_ns_ids_equal(&ns->head->ids, &ids)) {
   1676 		dev_err(ctrl->device,
   1677 			"identifiers changed for nsid %d\n", ns->head->ns_id);
   1678 		ret = -ENODEV;
   1679 	}
   1680 
   1681 out:
   1682 	kfree(id);
   1683 	return ret;
   1684 }
   1685 
   1686 static char nvme_pr_type(enum pr_type type)
   1687 {
   1688 	switch (type) {
   1689 	case PR_WRITE_EXCLUSIVE:
   1690 		return 1;
   1691 	case PR_EXCLUSIVE_ACCESS:
   1692 		return 2;
   1693 	case PR_WRITE_EXCLUSIVE_REG_ONLY:
   1694 		return 3;
   1695 	case PR_EXCLUSIVE_ACCESS_REG_ONLY:
   1696 		return 4;
   1697 	case PR_WRITE_EXCLUSIVE_ALL_REGS:
   1698 		return 5;
   1699 	case PR_EXCLUSIVE_ACCESS_ALL_REGS:
   1700 		return 6;
   1701 	default:
   1702 		return 0;
   1703 	}
   1704 };
   1705 
   1706 static int nvme_pr_command(struct block_device *bdev, u32 cdw10,
   1707 				u64 key, u64 sa_key, u8 op)
   1708 {
   1709 	struct nvme_ns_head *head = NULL;
   1710 	struct nvme_ns *ns;
   1711 	struct nvme_command c;
   1712 	int srcu_idx, ret;
   1713 	u8 data[16] = { 0, };
   1714 
   1715 	ns = nvme_get_ns_from_disk(bdev->bd_disk, &head, &srcu_idx);
   1716 	if (unlikely(!ns))
   1717 		return -EWOULDBLOCK;
   1718 
   1719 	put_unaligned_le64(key, &data[0]);
   1720 	put_unaligned_le64(sa_key, &data[8]);
   1721 
   1722 	memset(&c, 0, sizeof(c));
   1723 	c.common.opcode = op;
   1724 	c.common.nsid = cpu_to_le32(ns->head->ns_id);
   1725 	c.common.cdw10 = cpu_to_le32(cdw10);
   1726 
   1727 	ret = nvme_submit_sync_cmd(ns->queue, &c, data, 16);
   1728 	nvme_put_ns_from_disk(head, srcu_idx);
   1729 	return ret;
   1730 }
   1731 
   1732 static int nvme_pr_register(struct block_device *bdev, u64 old,
   1733 		u64 new, unsigned flags)
   1734 {
   1735 	u32 cdw10;
   1736 
   1737 	if (flags & ~PR_FL_IGNORE_KEY)
   1738 		return -EOPNOTSUPP;
   1739 
   1740 	cdw10 = old ? 2 : 0;
   1741 	cdw10 |= (flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0;
   1742 	cdw10 |= (1 << 30) | (1 << 31); /* PTPL=1 */
   1743 	return nvme_pr_command(bdev, cdw10, old, new, nvme_cmd_resv_register);
   1744 }
   1745 
   1746 static int nvme_pr_reserve(struct block_device *bdev, u64 key,
   1747 		enum pr_type type, unsigned flags)
   1748 {
   1749 	u32 cdw10;
   1750 
   1751 	if (flags & ~PR_FL_IGNORE_KEY)
   1752 		return -EOPNOTSUPP;
   1753 
   1754 	cdw10 = nvme_pr_type(type) << 8;
   1755 	cdw10 |= ((flags & PR_FL_IGNORE_KEY) ? 1 << 3 : 0);
   1756 	return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_acquire);
   1757 }
   1758 
   1759 static int nvme_pr_preempt(struct block_device *bdev, u64 old, u64 new,
   1760 		enum pr_type type, bool abort)
   1761 {
   1762 	u32 cdw10 = nvme_pr_type(type) << 8 | (abort ? 2 : 1);
   1763 	return nvme_pr_command(bdev, cdw10, old, new, nvme_cmd_resv_acquire);
   1764 }
   1765 
   1766 static int nvme_pr_clear(struct block_device *bdev, u64 key)
   1767 {
   1768 	u32 cdw10 = 1 | (key ? 1 << 3 : 0);
   1769 	return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_register);
   1770 }
   1771 
   1772 static int nvme_pr_release(struct block_device *bdev, u64 key, enum pr_type type)
   1773 {
   1774 	u32 cdw10 = nvme_pr_type(type) << 8 | (key ? 1 << 3 : 0);
   1775 	return nvme_pr_command(bdev, cdw10, key, 0, nvme_cmd_resv_release);
   1776 }
   1777 
   1778 static const struct pr_ops nvme_pr_ops = {
   1779 	.pr_register	= nvme_pr_register,
   1780 	.pr_reserve	= nvme_pr_reserve,
   1781 	.pr_release	= nvme_pr_release,
   1782 	.pr_preempt	= nvme_pr_preempt,
   1783 	.pr_clear	= nvme_pr_clear,
   1784 };
   1785 
   1786 #ifdef CONFIG_BLK_SED_OPAL
   1787 int nvme_sec_submit(void *data, u16 spsp, u8 secp, void *buffer, size_t len,
   1788 		bool send)
   1789 {
   1790 	struct nvme_ctrl *ctrl = data;
   1791 	struct nvme_command cmd;
   1792 
   1793 	memset(&cmd, 0, sizeof(cmd));
   1794 	if (send)
   1795 		cmd.common.opcode = nvme_admin_security_send;
   1796 	else
   1797 		cmd.common.opcode = nvme_admin_security_recv;
   1798 	cmd.common.nsid = 0;
   1799 	cmd.common.cdw10 = cpu_to_le32(((u32)secp) << 24 | ((u32)spsp) << 8);
   1800 	cmd.common.cdw11 = cpu_to_le32(len);
   1801 
   1802 	return __nvme_submit_sync_cmd(ctrl->admin_q, &cmd, NULL, buffer, len,
   1803 				      ADMIN_TIMEOUT, NVME_QID_ANY, 1, 0, false);
   1804 }
   1805 EXPORT_SYMBOL_GPL(nvme_sec_submit);
   1806 #endif /* CONFIG_BLK_SED_OPAL */
   1807 
   1808 static const struct block_device_operations nvme_fops = {
   1809 	.owner		= THIS_MODULE,
   1810 	.ioctl		= nvme_ioctl,
   1811 	.compat_ioctl	= nvme_ioctl,
   1812 	.open		= nvme_open,
   1813 	.release	= nvme_release,
   1814 	.getgeo		= nvme_getgeo,
   1815 	.revalidate_disk= nvme_revalidate_disk,
   1816 	.pr_ops		= &nvme_pr_ops,
   1817 };
   1818 
   1819 #ifdef CONFIG_NVME_MULTIPATH
   1820 static int nvme_ns_head_open(struct block_device *bdev, fmode_t mode)
   1821 {
   1822 	struct nvme_ns_head *head = bdev->bd_disk->private_data;
   1823 
   1824 	if (!kref_get_unless_zero(&head->ref))
   1825 		return -ENXIO;
   1826 	return 0;
   1827 }
   1828 
   1829 static void nvme_ns_head_release(struct gendisk *disk, fmode_t mode)
   1830 {
   1831 	nvme_put_ns_head(disk->private_data);
   1832 }
   1833 
   1834 const struct block_device_operations nvme_ns_head_ops = {
   1835 	.owner		= THIS_MODULE,
   1836 	.open		= nvme_ns_head_open,
   1837 	.release	= nvme_ns_head_release,
   1838 	.ioctl		= nvme_ioctl,
   1839 	.compat_ioctl	= nvme_ioctl,
   1840 	.getgeo		= nvme_getgeo,
   1841 	.pr_ops		= &nvme_pr_ops,
   1842 };
   1843 #endif /* CONFIG_NVME_MULTIPATH */
   1844 
   1845 static int nvme_wait_ready(struct nvme_ctrl *ctrl, u64 cap, bool enabled)
   1846 {
   1847 	unsigned long timeout =
   1848 		((NVME_CAP_TIMEOUT(cap) + 1) * HZ / 2) + jiffies;
   1849 	u32 csts, bit = enabled ? NVME_CSTS_RDY : 0;
   1850 	int ret;
   1851 
   1852 	while ((ret = ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &csts)) == 0) {
   1853 		if (csts == ~0)
   1854 			return -ENODEV;
   1855 		if ((csts & NVME_CSTS_RDY) == bit)
   1856 			break;
   1857 
   1858 		msleep(100);
   1859 		if (fatal_signal_pending(current))
   1860 			return -EINTR;
   1861 		if (time_after(jiffies, timeout)) {
   1862 			dev_err(ctrl->device,
   1863 				"Device not ready; aborting %s\n", enabled ?
   1864 						"initialisation" : "reset");
   1865 			return -ENODEV;
   1866 		}
   1867 	}
   1868 
   1869 	return ret;
   1870 }
   1871 
   1872 /*
   1873  * If the device has been passed off to us in an enabled state, just clear
   1874  * the enabled bit.  The spec says we should set the 'shutdown notification
   1875  * bits', but doing so may cause the device to complete commands to the
   1876  * admin queue ... and we don't know what memory that might be pointing at!
   1877  */
   1878 int nvme_disable_ctrl(struct nvme_ctrl *ctrl, u64 cap)
   1879 {
   1880 	int ret;
   1881 
   1882 	ctrl->ctrl_config &= ~NVME_CC_SHN_MASK;
   1883 	ctrl->ctrl_config &= ~NVME_CC_ENABLE;
   1884 
   1885 	ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
   1886 	if (ret)
   1887 		return ret;
   1888 
   1889 	if (ctrl->quirks & NVME_QUIRK_DELAY_BEFORE_CHK_RDY)
   1890 		msleep(NVME_QUIRK_DELAY_AMOUNT);
   1891 
   1892 	return nvme_wait_ready(ctrl, cap, false);
   1893 }
   1894 EXPORT_SYMBOL_GPL(nvme_disable_ctrl);
   1895 
   1896 int nvme_enable_ctrl(struct nvme_ctrl *ctrl, u64 cap)
   1897 {
   1898 	/*
   1899 	 * Default to a 4K page size, with the intention to update this
   1900 	 * path in the future to accomodate architectures with differing
   1901 	 * kernel and IO page sizes.
   1902 	 */
   1903 	unsigned dev_page_min = NVME_CAP_MPSMIN(cap) + 12, page_shift = 12;
   1904 	int ret;
   1905 
   1906 	if (page_shift < dev_page_min) {
   1907 		dev_err(ctrl->device,
   1908 			"Minimum device page size %u too large for host (%u)\n",
   1909 			1 << dev_page_min, 1 << page_shift);
   1910 		return -ENODEV;
   1911 	}
   1912 
   1913 	ctrl->page_size = 1 << page_shift;
   1914 
   1915 	ctrl->ctrl_config = NVME_CC_CSS_NVM;
   1916 	ctrl->ctrl_config |= (page_shift - 12) << NVME_CC_MPS_SHIFT;
   1917 	ctrl->ctrl_config |= NVME_CC_AMS_RR | NVME_CC_SHN_NONE;
   1918 	ctrl->ctrl_config |= NVME_CC_IOSQES | NVME_CC_IOCQES;
   1919 	ctrl->ctrl_config |= NVME_CC_ENABLE;
   1920 
   1921 	ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
   1922 	if (ret)
   1923 		return ret;
   1924 	return nvme_wait_ready(ctrl, cap, true);
   1925 }
   1926 EXPORT_SYMBOL_GPL(nvme_enable_ctrl);
   1927 
   1928 int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl)
   1929 {
   1930 	unsigned long timeout = jiffies + (ctrl->shutdown_timeout * HZ);
   1931 	u32 csts;
   1932 	int ret;
   1933 
   1934 	ctrl->ctrl_config &= ~NVME_CC_SHN_MASK;
   1935 	ctrl->ctrl_config |= NVME_CC_SHN_NORMAL;
   1936 
   1937 	ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
   1938 	if (ret)
   1939 		return ret;
   1940 
   1941 	while ((ret = ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &csts)) == 0) {
   1942 		if ((csts & NVME_CSTS_SHST_MASK) == NVME_CSTS_SHST_CMPLT)
   1943 			break;
   1944 
   1945 		msleep(100);
   1946 		if (fatal_signal_pending(current))
   1947 			return -EINTR;
   1948 		if (time_after(jiffies, timeout)) {
   1949 			dev_err(ctrl->device,
   1950 				"Device shutdown incomplete; abort shutdown\n");
   1951 			return -ENODEV;
   1952 		}
   1953 	}
   1954 
   1955 	return ret;
   1956 }
   1957 EXPORT_SYMBOL_GPL(nvme_shutdown_ctrl);
   1958 
   1959 static void nvme_set_queue_limits(struct nvme_ctrl *ctrl,
   1960 		struct request_queue *q)
   1961 {
   1962 	bool vwc = false;
   1963 
   1964 	if (ctrl->max_hw_sectors) {
   1965 		u32 max_segments =
   1966 			(ctrl->max_hw_sectors / (ctrl->page_size >> 9)) + 1;
   1967 
   1968 		max_segments = min_not_zero(max_segments, ctrl->max_segments);
   1969 		blk_queue_max_hw_sectors(q, ctrl->max_hw_sectors);
   1970 		blk_queue_max_segments(q, min_t(u32, max_segments, USHRT_MAX));
   1971 	}
   1972 	if ((ctrl->quirks & NVME_QUIRK_STRIPE_SIZE) &&
   1973 	    is_power_of_2(ctrl->max_hw_sectors))
   1974 		blk_queue_chunk_sectors(q, ctrl->max_hw_sectors);
   1975 	blk_queue_virt_boundary(q, ctrl->page_size - 1);
   1976 	if (ctrl->vwc & NVME_CTRL_VWC_PRESENT)
   1977 		vwc = true;
   1978 	blk_queue_write_cache(q, vwc, vwc);
   1979 }
   1980 
   1981 static int nvme_configure_timestamp(struct nvme_ctrl *ctrl)
   1982 {
   1983 	__le64 ts;
   1984 	int ret;
   1985 
   1986 	if (!(ctrl->oncs & NVME_CTRL_ONCS_TIMESTAMP))
   1987 		return 0;
   1988 
   1989 	ts = cpu_to_le64(ktime_to_ms(ktime_get_real()));
   1990 	ret = nvme_set_features(ctrl, NVME_FEAT_TIMESTAMP, 0, &ts, sizeof(ts),
   1991 			NULL);
   1992 	if (ret)
   1993 		dev_warn_once(ctrl->device,
   1994 			"could not set timestamp (%d)\n", ret);
   1995 	return ret;
   1996 }
   1997 
   1998 static int nvme_configure_acre(struct nvme_ctrl *ctrl)
   1999 {
   2000 	struct nvme_feat_host_behavior *host;
   2001 	int ret;
   2002 
   2003 	/* Don't bother enabling the feature if retry delay is not reported */
   2004 	if (!ctrl->crdt[0])
   2005 		return 0;
   2006 
   2007 	host = kzalloc(sizeof(*host), GFP_KERNEL);
   2008 	if (!host)
   2009 		return 0;
   2010 
   2011 	host->acre = NVME_ENABLE_ACRE;
   2012 	ret = nvme_set_features(ctrl, NVME_FEAT_HOST_BEHAVIOR, 0,
   2013 				host, sizeof(*host), NULL);
   2014 	kfree(host);
   2015 	return ret;
   2016 }
   2017 
   2018 static int nvme_configure_apst(struct nvme_ctrl *ctrl)
   2019 {
   2020 	/*
   2021 	 * APST (Autonomous Power State Transition) lets us program a
   2022 	 * table of power state transitions that the controller will
   2023 	 * perform automatically.  We configure it with a simple
   2024 	 * heuristic: we are willing to spend at most 2% of the time
   2025 	 * transitioning between power states.  Therefore, when running
   2026 	 * in any given state, we will enter the next lower-power
   2027 	 * non-operational state after waiting 50 * (enlat + exlat)
   2028 	 * microseconds, as long as that state's exit latency is under
   2029 	 * the requested maximum latency.
   2030 	 *
   2031 	 * We will not autonomously enter any non-operational state for
   2032 	 * which the total latency exceeds ps_max_latency_us.  Users
   2033 	 * can set ps_max_latency_us to zero to turn off APST.
   2034 	 */
   2035 
   2036 	unsigned apste;
   2037 	struct nvme_feat_auto_pst *table;
   2038 	u64 max_lat_us = 0;
   2039 	int max_ps = -1;
   2040 	int ret;
   2041 
   2042 	/*
   2043 	 * If APST isn't supported or if we haven't been initialized yet,
   2044 	 * then don't do anything.
   2045 	 */
   2046 	if (!ctrl->apsta)
   2047 		return 0;
   2048 
   2049 	if (ctrl->npss > 31) {
   2050 		dev_warn(ctrl->device, "NPSS is invalid; not using APST\n");
   2051 		return 0;
   2052 	}
   2053 
   2054 	table = kzalloc(sizeof(*table), GFP_KERNEL);
   2055 	if (!table)
   2056 		return 0;
   2057 
   2058 	if (!ctrl->apst_enabled || ctrl->ps_max_latency_us == 0) {
   2059 		/* Turn off APST. */
   2060 		apste = 0;
   2061 		dev_dbg(ctrl->device, "APST disabled\n");
   2062 	} else {
   2063 		__le64 target = cpu_to_le64(0);
   2064 		int state;
   2065 
   2066 		/*
   2067 		 * Walk through all states from lowest- to highest-power.
   2068 		 * According to the spec, lower-numbered states use more
   2069 		 * power.  NPSS, despite the name, is the index of the
   2070 		 * lowest-power state, not the number of states.
   2071 		 */
   2072 		for (state = (int)ctrl->npss; state >= 0; state--) {
   2073 			u64 total_latency_us, exit_latency_us, transition_ms;
   2074 
   2075 			if (target)
   2076 				table->entries[state] = target;
   2077 
   2078 			/*
   2079 			 * Don't allow transitions to the deepest state
   2080 			 * if it's quirked off.
   2081 			 */
   2082 			if (state == ctrl->npss &&
   2083 			    (ctrl->quirks & NVME_QUIRK_NO_DEEPEST_PS))
   2084 				continue;
   2085 
   2086 			/*
   2087 			 * Is this state a useful non-operational state for
   2088 			 * higher-power states to autonomously transition to?
   2089 			 */
   2090 			if (!(ctrl->psd[state].flags &
   2091 			      NVME_PS_FLAGS_NON_OP_STATE))
   2092 				continue;
   2093 
   2094 			exit_latency_us =
   2095 				(u64)le32_to_cpu(ctrl->psd[state].exit_lat);
   2096 			if (exit_latency_us > ctrl->ps_max_latency_us)
   2097 				continue;
   2098 
   2099 			total_latency_us =
   2100 				exit_latency_us +
   2101 				le32_to_cpu(ctrl->psd[state].entry_lat);
   2102 
   2103 			/*
   2104 			 * This state is good.  Use it as the APST idle
   2105 			 * target for higher power states.
   2106 			 */
   2107 			transition_ms = total_latency_us + 19;
   2108 			do_div(transition_ms, 20);
   2109 			if (transition_ms > (1 << 24) - 1)
   2110 				transition_ms = (1 << 24) - 1;
   2111 
   2112 			target = cpu_to_le64((state << 3) |
   2113 					     (transition_ms << 8));
   2114 
   2115 			if (max_ps == -1)
   2116 				max_ps = state;
   2117 
   2118 			if (total_latency_us > max_lat_us)
   2119 				max_lat_us = total_latency_us;
   2120 		}
   2121 
   2122 		apste = 1;
   2123 
   2124 		if (max_ps == -1) {
   2125 			dev_dbg(ctrl->device, "APST enabled but no non-operational states are available\n");
   2126 		} else {
   2127 			dev_dbg(ctrl->device, "APST enabled: max PS = %d, max round-trip latency = %lluus, table = %*phN\n",
   2128 				max_ps, max_lat_us, (int)sizeof(*table), table);
   2129 		}
   2130 	}
   2131 
   2132 	ret = nvme_set_features(ctrl, NVME_FEAT_AUTO_PST, apste,
   2133 				table, sizeof(*table), NULL);
   2134 	if (ret)
   2135 		dev_err(ctrl->device, "failed to set APST feature (%d)\n", ret);
   2136 
   2137 	kfree(table);
   2138 	return ret;
   2139 }
   2140 
   2141 static void nvme_set_latency_tolerance(struct device *dev, s32 val)
   2142 {
   2143 	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
   2144 	u64 latency;
   2145 
   2146 	switch (val) {
   2147 	case PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT:
   2148 	case PM_QOS_LATENCY_ANY:
   2149 		latency = U64_MAX;
   2150 		break;
   2151 
   2152 	default:
   2153 		latency = val;
   2154 	}
   2155 
   2156 	if (ctrl->ps_max_latency_us != latency) {
   2157 		ctrl->ps_max_latency_us = latency;
   2158 		nvme_configure_apst(ctrl);
   2159 	}
   2160 }
   2161 
   2162 struct nvme_core_quirk_entry {
   2163 	/*
   2164 	 * NVMe model and firmware strings are padded with spaces.  For
   2165 	 * simplicity, strings in the quirk table are padded with NULLs
   2166 	 * instead.
   2167 	 */
   2168 	u16 vid;
   2169 	const char *mn;
   2170 	const char *fr;
   2171 	unsigned long quirks;
   2172 };
   2173 
   2174 static const struct nvme_core_quirk_entry core_quirks[] = {
   2175 	{
   2176 		/*
   2177 		 * This Toshiba device seems to die using any APST states.  See:
   2178 		 * https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1678184/comments/11
   2179 		 */
   2180 		.vid = 0x1179,
   2181 		.mn = "THNSF5256GPUK TOSHIBA",
   2182 		.quirks = NVME_QUIRK_NO_APST,
   2183 	}
   2184 };
   2185 
   2186 /* match is null-terminated but idstr is space-padded. */
   2187 static bool string_matches(const char *idstr, const char *match, size_t len)
   2188 {
   2189 	size_t matchlen;
   2190 
   2191 	if (!match)
   2192 		return true;
   2193 
   2194 	matchlen = strlen(match);
   2195 	WARN_ON_ONCE(matchlen > len);
   2196 
   2197 	if (memcmp(idstr, match, matchlen))
   2198 		return false;
   2199 
   2200 	for (; matchlen < len; matchlen++)
   2201 		if (idstr[matchlen] != ' ')
   2202 			return false;
   2203 
   2204 	return true;
   2205 }
   2206 
   2207 static bool quirk_matches(const struct nvme_id_ctrl *id,
   2208 			  const struct nvme_core_quirk_entry *q)
   2209 {
   2210 	return q->vid == le16_to_cpu(id->vid) &&
   2211 		string_matches(id->mn, q->mn, sizeof(id->mn)) &&
   2212 		string_matches(id->fr, q->fr, sizeof(id->fr));
   2213 }
   2214 
   2215 static void nvme_init_subnqn(struct nvme_subsystem *subsys, struct nvme_ctrl *ctrl,
   2216 		struct nvme_id_ctrl *id)
   2217 {
   2218 	size_t nqnlen;
   2219 	int off;
   2220 
   2221 	if(!(ctrl->quirks & NVME_QUIRK_IGNORE_DEV_SUBNQN)) {
   2222 		nqnlen = strnlen(id->subnqn, NVMF_NQN_SIZE);
   2223 		if (nqnlen > 0 && nqnlen < NVMF_NQN_SIZE) {
   2224 			strlcpy(subsys->subnqn, id->subnqn, NVMF_NQN_SIZE);
   2225 			return;
   2226 		}
   2227 
   2228 		if (ctrl->vs >= NVME_VS(1, 2, 1))
   2229 			dev_warn(ctrl->device, "missing or invalid SUBNQN field.\n");
   2230 	}
   2231 
   2232 	/* Generate a "fake" NQN per Figure 254 in NVMe 1.3 + ECN 001 */
   2233 	off = snprintf(subsys->subnqn, NVMF_NQN_SIZE,
   2234 			"nqn.2014.08.org.nvmexpress:%04x%04x",
   2235 			le16_to_cpu(id->vid), le16_to_cpu(id->ssvid));
   2236 	memcpy(subsys->subnqn + off, id->sn, sizeof(id->sn));
   2237 	off += sizeof(id->sn);
   2238 	memcpy(subsys->subnqn + off, id->mn, sizeof(id->mn));
   2239 	off += sizeof(id->mn);
   2240 	memset(subsys->subnqn + off, 0, sizeof(subsys->subnqn) - off);
   2241 }
   2242 
   2243 static void __nvme_release_subsystem(struct nvme_subsystem *subsys)
   2244 {
   2245 	ida_simple_remove(&nvme_subsystems_ida, subsys->instance);
   2246 	kfree(subsys);
   2247 }
   2248 
   2249 static void nvme_release_subsystem(struct device *dev)
   2250 {
   2251 	__nvme_release_subsystem(container_of(dev, struct nvme_subsystem, dev));
   2252 }
   2253 
   2254 static void nvme_destroy_subsystem(struct kref *ref)
   2255 {
   2256 	struct nvme_subsystem *subsys =
   2257 			container_of(ref, struct nvme_subsystem, ref);
   2258 
   2259 	mutex_lock(&nvme_subsystems_lock);
   2260 	list_del(&subsys->entry);
   2261 	mutex_unlock(&nvme_subsystems_lock);
   2262 
   2263 	ida_destroy(&subsys->ns_ida);
   2264 	device_del(&subsys->dev);
   2265 	put_device(&subsys->dev);
   2266 }
   2267 
   2268 static void nvme_put_subsystem(struct nvme_subsystem *subsys)
   2269 {
   2270 	kref_put(&subsys->ref, nvme_destroy_subsystem);
   2271 }
   2272 
   2273 static struct nvme_subsystem *__nvme_find_get_subsystem(const char *subsysnqn)
   2274 {
   2275 	struct nvme_subsystem *subsys;
   2276 
   2277 	lockdep_assert_held(&nvme_subsystems_lock);
   2278 
   2279 	list_for_each_entry(subsys, &nvme_subsystems, entry) {
   2280 		if (strcmp(subsys->subnqn, subsysnqn))
   2281 			continue;
   2282 		if (!kref_get_unless_zero(&subsys->ref))
   2283 			continue;
   2284 		return subsys;
   2285 	}
   2286 
   2287 	return NULL;
   2288 }
   2289 
   2290 #define SUBSYS_ATTR_RO(_name, _mode, _show)			\
   2291 	struct device_attribute subsys_attr_##_name = \
   2292 		__ATTR(_name, _mode, _show, NULL)
   2293 
   2294 static ssize_t nvme_subsys_show_nqn(struct device *dev,
   2295 				    struct device_attribute *attr,
   2296 				    char *buf)
   2297 {
   2298 	struct nvme_subsystem *subsys =
   2299 		container_of(dev, struct nvme_subsystem, dev);
   2300 
   2301 	return snprintf(buf, PAGE_SIZE, "%s\n", subsys->subnqn);
   2302 }
   2303 static SUBSYS_ATTR_RO(subsysnqn, S_IRUGO, nvme_subsys_show_nqn);
   2304 
   2305 #define nvme_subsys_show_str_function(field)				\
   2306 static ssize_t subsys_##field##_show(struct device *dev,		\
   2307 			    struct device_attribute *attr, char *buf)	\
   2308 {									\
   2309 	struct nvme_subsystem *subsys =					\
   2310 		container_of(dev, struct nvme_subsystem, dev);		\
   2311 	return sprintf(buf, "%.*s\n",					\
   2312 		       (int)sizeof(subsys->field), subsys->field);	\
   2313 }									\
   2314 static SUBSYS_ATTR_RO(field, S_IRUGO, subsys_##field##_show);
   2315 
   2316 nvme_subsys_show_str_function(model);
   2317 nvme_subsys_show_str_function(serial);
   2318 nvme_subsys_show_str_function(firmware_rev);
   2319 
   2320 static struct attribute *nvme_subsys_attrs[] = {
   2321 	&subsys_attr_model.attr,
   2322 	&subsys_attr_serial.attr,
   2323 	&subsys_attr_firmware_rev.attr,
   2324 	&subsys_attr_subsysnqn.attr,
   2325 #ifdef CONFIG_NVME_MULTIPATH
   2326 	&subsys_attr_iopolicy.attr,
   2327 #endif
   2328 	NULL,
   2329 };
   2330 
   2331 static struct attribute_group nvme_subsys_attrs_group = {
   2332 	.attrs = nvme_subsys_attrs,
   2333 };
   2334 
   2335 static const struct attribute_group *nvme_subsys_attrs_groups[] = {
   2336 	&nvme_subsys_attrs_group,
   2337 	NULL,
   2338 };
   2339 
   2340 static int nvme_active_ctrls(struct nvme_subsystem *subsys)
   2341 {
   2342 	int count = 0;
   2343 	struct nvme_ctrl *ctrl;
   2344 
   2345 	mutex_lock(&subsys->lock);
   2346 	list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
   2347 		if (ctrl->state != NVME_CTRL_DELETING &&
   2348 		    ctrl->state != NVME_CTRL_DEAD)
   2349 			count++;
   2350 	}
   2351 	mutex_unlock(&subsys->lock);
   2352 
   2353 	return count;
   2354 }
   2355 
   2356 static int nvme_init_subsystem(struct nvme_ctrl *ctrl, struct nvme_id_ctrl *id)
   2357 {
   2358 	struct nvme_subsystem *subsys, *found;
   2359 	int ret;
   2360 
   2361 	subsys = kzalloc(sizeof(*subsys), GFP_KERNEL);
   2362 	if (!subsys)
   2363 		return -ENOMEM;
   2364 	ret = ida_simple_get(&nvme_subsystems_ida, 0, 0, GFP_KERNEL);
   2365 	if (ret < 0) {
   2366 		kfree(subsys);
   2367 		return ret;
   2368 	}
   2369 	subsys->instance = ret;
   2370 	mutex_init(&subsys->lock);
   2371 	kref_init(&subsys->ref);
   2372 	INIT_LIST_HEAD(&subsys->ctrls);
   2373 	INIT_LIST_HEAD(&subsys->nsheads);
   2374 	nvme_init_subnqn(subsys, ctrl, id);
   2375 	memcpy(subsys->serial, id->sn, sizeof(subsys->serial));
   2376 	memcpy(subsys->model, id->mn, sizeof(subsys->model));
   2377 	memcpy(subsys->firmware_rev, id->fr, sizeof(subsys->firmware_rev));
   2378 	subsys->vendor_id = le16_to_cpu(id->vid);
   2379 	subsys->cmic = id->cmic;
   2380 #ifdef CONFIG_NVME_MULTIPATH
   2381 	subsys->iopolicy = NVME_IOPOLICY_NUMA;
   2382 #endif
   2383 
   2384 	subsys->dev.class = nvme_subsys_class;
   2385 	subsys->dev.release = nvme_release_subsystem;
   2386 	subsys->dev.groups = nvme_subsys_attrs_groups;
   2387 	dev_set_name(&subsys->dev, "nvme-subsys%d", subsys->instance);
   2388 	device_initialize(&subsys->dev);
   2389 
   2390 	mutex_lock(&nvme_subsystems_lock);
   2391 	found = __nvme_find_get_subsystem(subsys->subnqn);
   2392 	if (found) {
   2393 		/*
   2394 		 * Verify that the subsystem actually supports multiple
   2395 		 * controllers, else bail out.
   2396 		 */
   2397 		if (!(ctrl->opts && ctrl->opts->discovery_nqn) &&
   2398 		    nvme_active_ctrls(found) && !(id->cmic & (1 << 1))) {
   2399 			dev_err(ctrl->device,
   2400 				"ignoring ctrl due to duplicate subnqn (%s).\n",
   2401 				found->subnqn);
   2402 			nvme_put_subsystem(found);
   2403 			ret = -EINVAL;
   2404 			goto out_unlock;
   2405 		}
   2406 
   2407 		__nvme_release_subsystem(subsys);
   2408 		subsys = found;
   2409 	} else {
   2410 		ret = device_add(&subsys->dev);
   2411 		if (ret) {
   2412 			dev_err(ctrl->device,
   2413 				"failed to register subsystem device.\n");
   2414 			goto out_unlock;
   2415 		}
   2416 		ida_init(&subsys->ns_ida);
   2417 		list_add_tail(&subsys->entry, &nvme_subsystems);
   2418 	}
   2419 
   2420 	ctrl->subsys = subsys;
   2421 	mutex_unlock(&nvme_subsystems_lock);
   2422 
   2423 	if (sysfs_create_link(&subsys->dev.kobj, &ctrl->device->kobj,
   2424 			dev_name(ctrl->device))) {
   2425 		dev_err(ctrl->device,
   2426 			"failed to create sysfs link from subsystem.\n");
   2427 		/* the transport driver will eventually put the subsystem */
   2428 		return -EINVAL;
   2429 	}
   2430 
   2431 	mutex_lock(&subsys->lock);
   2432 	list_add_tail(&ctrl->subsys_entry, &subsys->ctrls);
   2433 	mutex_unlock(&subsys->lock);
   2434 
   2435 	return 0;
   2436 
   2437 out_unlock:
   2438 	mutex_unlock(&nvme_subsystems_lock);
   2439 	put_device(&subsys->dev);
   2440 	return ret;
   2441 }
   2442 
   2443 int nvme_get_log(struct nvme_ctrl *ctrl, u32 nsid, u8 log_page, u8 lsp,
   2444 		void *log, size_t size, u64 offset)
   2445 {
   2446 	struct nvme_command c = { };
   2447 	unsigned long dwlen = size / 4 - 1;
   2448 
   2449 	c.get_log_page.opcode = nvme_admin_get_log_page;
   2450 	c.get_log_page.nsid = cpu_to_le32(nsid);
   2451 	c.get_log_page.lid = log_page;
   2452 	c.get_log_page.lsp = lsp;
   2453 	c.get_log_page.numdl = cpu_to_le16(dwlen & ((1 << 16) - 1));
   2454 	c.get_log_page.numdu = cpu_to_le16(dwlen >> 16);
   2455 	c.get_log_page.lpol = cpu_to_le32(lower_32_bits(offset));
   2456 	c.get_log_page.lpou = cpu_to_le32(upper_32_bits(offset));
   2457 
   2458 	return nvme_submit_sync_cmd(ctrl->admin_q, &c, log, size);
   2459 }
   2460 
   2461 static int nvme_get_effects_log(struct nvme_ctrl *ctrl)
   2462 {
   2463 	int ret;
   2464 
   2465 	if (!ctrl->effects)
   2466 		ctrl->effects = kzalloc(sizeof(*ctrl->effects), GFP_KERNEL);
   2467 
   2468 	if (!ctrl->effects)
   2469 		return 0;
   2470 
   2471 	ret = nvme_get_log(ctrl, NVME_NSID_ALL, NVME_LOG_CMD_EFFECTS, 0,
   2472 			ctrl->effects, sizeof(*ctrl->effects), 0);
   2473 	if (ret) {
   2474 		kfree(ctrl->effects);
   2475 		ctrl->effects = NULL;
   2476 	}
   2477 	return ret;
   2478 }
   2479 
   2480 /*
   2481  * Initialize the cached copies of the Identify data and various controller
   2482  * register in our nvme_ctrl structure.  This should be called as soon as
   2483  * the admin queue is fully up and running.
   2484  */
   2485 int nvme_init_identify(struct nvme_ctrl *ctrl)
   2486 {
   2487 	struct nvme_id_ctrl *id;
   2488 	u64 cap;
   2489 	int ret, page_shift;
   2490 	u32 max_hw_sectors;
   2491 	bool prev_apst_enabled;
   2492 
   2493 	ret = ctrl->ops->reg_read32(ctrl, NVME_REG_VS, &ctrl->vs);
   2494 	if (ret) {
   2495 		dev_err(ctrl->device, "Reading VS failed (%d)\n", ret);
   2496 		return ret;
   2497 	}
   2498 
   2499 	ret = ctrl->ops->reg_read64(ctrl, NVME_REG_CAP, &cap);
   2500 	if (ret) {
   2501 		dev_err(ctrl->device, "Reading CAP failed (%d)\n", ret);
   2502 		return ret;
   2503 	}
   2504 	page_shift = NVME_CAP_MPSMIN(cap) + 12;
   2505 
   2506 	if (ctrl->vs >= NVME_VS(1, 1, 0))
   2507 		ctrl->subsystem = NVME_CAP_NSSRC(cap);
   2508 
   2509 	ret = nvme_identify_ctrl(ctrl, &id);
   2510 	if (ret) {
   2511 		dev_err(ctrl->device, "Identify Controller failed (%d)\n", ret);
   2512 		return -EIO;
   2513 	}
   2514 
   2515 	if (id->lpa & NVME_CTRL_LPA_CMD_EFFECTS_LOG) {
   2516 		ret = nvme_get_effects_log(ctrl);
   2517 		if (ret < 0)
   2518 			goto out_free;
   2519 	}
   2520 
   2521 	if (!ctrl->identified) {
   2522 		int i;
   2523 
   2524 		ret = nvme_init_subsystem(ctrl, id);
   2525 		if (ret)
   2526 			goto out_free;
   2527 
   2528 		/*
   2529 		 * Check for quirks.  Quirk can depend on firmware version,
   2530 		 * so, in principle, the set of quirks present can change
   2531 		 * across a reset.  As a possible future enhancement, we
   2532 		 * could re-scan for quirks every time we reinitialize
   2533 		 * the device, but we'd have to make sure that the driver
   2534 		 * behaves intelligently if the quirks change.
   2535 		 */
   2536 		for (i = 0; i < ARRAY_SIZE(core_quirks); i++) {
   2537 			if (quirk_matches(id, &core_quirks[i]))
   2538 				ctrl->quirks |= core_quirks[i].quirks;
   2539 		}
   2540 	}
   2541 
   2542 	if (force_apst && (ctrl->quirks & NVME_QUIRK_NO_DEEPEST_PS)) {
   2543 		dev_warn(ctrl->device, "forcibly allowing all power states due to nvme_core.force_apst -- use at your own risk\n");
   2544 		ctrl->quirks &= ~NVME_QUIRK_NO_DEEPEST_PS;
   2545 	}
   2546 
   2547 	ctrl->crdt[0] = le16_to_cpu(id->crdt1);
   2548 	ctrl->crdt[1] = le16_to_cpu(id->crdt2);
   2549 	ctrl->crdt[2] = le16_to_cpu(id->crdt3);
   2550 
   2551 	ctrl->oacs = le16_to_cpu(id->oacs);
   2552 	ctrl->oncs = le16_to_cpup(&id->oncs);
   2553 	ctrl->oaes = le32_to_cpu(id->oaes);
   2554 	atomic_set(&ctrl->abort_limit, id->acl + 1);
   2555 	ctrl->vwc = id->vwc;
   2556 	if (id->mdts)
   2557 		max_hw_sectors = 1 << (id->mdts + page_shift - 9);
   2558 	else
   2559 		max_hw_sectors = UINT_MAX;
   2560 	ctrl->max_hw_sectors =
   2561 		min_not_zero(ctrl->max_hw_sectors, max_hw_sectors);
   2562 
   2563 	nvme_set_queue_limits(ctrl, ctrl->admin_q);
   2564 	ctrl->sgls = le32_to_cpu(id->sgls);
   2565 	ctrl->kas = le16_to_cpu(id->kas);
   2566 	ctrl->max_namespaces = le32_to_cpu(id->mnan);
   2567 	ctrl->ctratt = le32_to_cpu(id->ctratt);
   2568 
   2569 	if (id->rtd3e) {
   2570 		/* us -> s */
   2571 		u32 transition_time = le32_to_cpu(id->rtd3e) / 1000000;
   2572 
   2573 		ctrl->shutdown_timeout = clamp_t(unsigned int, transition_time,
   2574 						 shutdown_timeout, 60);
   2575 
   2576 		if (ctrl->shutdown_timeout != shutdown_timeout)
   2577 			dev_info(ctrl->device,
   2578 				 "Shutdown timeout set to %u seconds\n",
   2579 				 ctrl->shutdown_timeout);
   2580 	} else
   2581 		ctrl->shutdown_timeout = shutdown_timeout;
   2582 
   2583 	ctrl->npss = id->npss;
   2584 	ctrl->apsta = id->apsta;
   2585 	prev_apst_enabled = ctrl->apst_enabled;
   2586 	if (ctrl->quirks & NVME_QUIRK_NO_APST) {
   2587 		if (force_apst && id->apsta) {
   2588 			dev_warn(ctrl->device, "forcibly allowing APST due to nvme_core.force_apst -- use at your own risk\n");
   2589 			ctrl->apst_enabled = true;
   2590 		} else {
   2591 			ctrl->apst_enabled = false;
   2592 		}
   2593 	} else {
   2594 		ctrl->apst_enabled = id->apsta;
   2595 	}
   2596 	memcpy(ctrl->psd, id->psd, sizeof(ctrl->psd));
   2597 
   2598 	if (ctrl->ops->flags & NVME_F_FABRICS) {
   2599 		ctrl->icdoff = le16_to_cpu(id->icdoff);
   2600 		ctrl->ioccsz = le32_to_cpu(id->ioccsz);
   2601 		ctrl->iorcsz = le32_to_cpu(id->iorcsz);
   2602 		ctrl->maxcmd = le16_to_cpu(id->maxcmd);
   2603 
   2604 		/*
   2605 		 * In fabrics we need to verify the cntlid matches the
   2606 		 * admin connect
   2607 		 */
   2608 		if (ctrl->cntlid != le16_to_cpu(id->cntlid)) {
   2609 			ret = -EINVAL;
   2610 			goto out_free;
   2611 		}
   2612 
   2613 		if (!ctrl->opts->discovery_nqn && !ctrl->kas) {
   2614 			dev_err(ctrl->device,
   2615 				"keep-alive support is mandatory for fabrics\n");
   2616 			ret = -EINVAL;
   2617 			goto out_free;
   2618 		}
   2619 	} else {
   2620 		ctrl->cntlid = le16_to_cpu(id->cntlid);
   2621 		ctrl->hmpre = le32_to_cpu(id->hmpre);
   2622 		ctrl->hmmin = le32_to_cpu(id->hmmin);
   2623 		ctrl->hmminds = le32_to_cpu(id->hmminds);
   2624 		ctrl->hmmaxd = le16_to_cpu(id->hmmaxd);
   2625 	}
   2626 
   2627 	ret = nvme_mpath_init(ctrl, id);
   2628 	kfree(id);
   2629 
   2630 	if (ret < 0)
   2631 		return ret;
   2632 
   2633 	if (ctrl->apst_enabled && !prev_apst_enabled)
   2634 		dev_pm_qos_expose_latency_tolerance(ctrl->device);
   2635 	else if (!ctrl->apst_enabled && prev_apst_enabled)
   2636 		dev_pm_qos_hide_latency_tolerance(ctrl->device);
   2637 
   2638 	ret = nvme_configure_apst(ctrl);
   2639 	if (ret < 0)
   2640 		return ret;
   2641 	
   2642 	ret = nvme_configure_timestamp(ctrl);
   2643 	if (ret < 0)
   2644 		return ret;
   2645 
   2646 	ret = nvme_configure_directives(ctrl);
   2647 	if (ret < 0)
   2648 		return ret;
   2649 
   2650 	ret = nvme_configure_acre(ctrl);
   2651 	if (ret < 0)
   2652 		return ret;
   2653 
   2654 	ctrl->identified = true;
   2655 
   2656 	return 0;
   2657 
   2658 out_free:
   2659 	kfree(id);
   2660 	return ret;
   2661 }
   2662 EXPORT_SYMBOL_GPL(nvme_init_identify);
   2663 
   2664 static int nvme_dev_open(struct inode *inode, struct file *file)
   2665 {
   2666 	struct nvme_ctrl *ctrl =
   2667 		container_of(inode->i_cdev, struct nvme_ctrl, cdev);
   2668 
   2669 	switch (ctrl->state) {
   2670 	case NVME_CTRL_LIVE:
   2671 	case NVME_CTRL_ADMIN_ONLY:
   2672 		break;
   2673 	default:
   2674 		return -EWOULDBLOCK;
   2675 	}
   2676 
   2677 	file->private_data = ctrl;
   2678 	return 0;
   2679 }
   2680 
   2681 static int nvme_dev_user_cmd(struct nvme_ctrl *ctrl, void __user *argp)
   2682 {
   2683 	struct nvme_ns *ns;
   2684 	int ret;
   2685 
   2686 	down_read(&ctrl->namespaces_rwsem);
   2687 	if (list_empty(&ctrl->namespaces)) {
   2688 		ret = -ENOTTY;
   2689 		goto out_unlock;
   2690 	}
   2691 
   2692 	ns = list_first_entry(&ctrl->namespaces, struct nvme_ns, list);
   2693 	if (ns != list_last_entry(&ctrl->namespaces, struct nvme_ns, list)) {
   2694 		dev_warn(ctrl->device,
   2695 			"NVME_IOCTL_IO_CMD not supported when multiple namespaces present!\n");
   2696 		ret = -EINVAL;
   2697 		goto out_unlock;
   2698 	}
   2699 
   2700 	dev_warn(ctrl->device,
   2701 		"using deprecated NVME_IOCTL_IO_CMD ioctl on the char device!\n");
   2702 	kref_get(&ns->kref);
   2703 	up_read(&ctrl->namespaces_rwsem);
   2704 
   2705 	ret = nvme_user_cmd(ctrl, ns, argp);
   2706 	nvme_put_ns(ns);
   2707 	return ret;
   2708 
   2709 out_unlock:
   2710 	up_read(&ctrl->namespaces_rwsem);
   2711 	return ret;
   2712 }
   2713 
   2714 static long nvme_dev_ioctl(struct file *file, unsigned int cmd,
   2715 		unsigned long arg)
   2716 {
   2717 	struct nvme_ctrl *ctrl = file->private_data;
   2718 	void __user *argp = (void __user *)arg;
   2719 
   2720 	switch (cmd) {
   2721 	case NVME_IOCTL_ADMIN_CMD:
   2722 		return nvme_user_cmd(ctrl, NULL, argp);
   2723 	case NVME_IOCTL_IO_CMD:
   2724 		return nvme_dev_user_cmd(ctrl, argp);
   2725 	case NVME_IOCTL_RESET:
   2726 		dev_warn(ctrl->device, "resetting controller\n");
   2727 		return nvme_reset_ctrl_sync(ctrl);
   2728 	case NVME_IOCTL_SUBSYS_RESET:
   2729 		return nvme_reset_subsystem(ctrl);
   2730 	case NVME_IOCTL_RESCAN:
   2731 		nvme_queue_scan(ctrl);
   2732 		return 0;
   2733 	default:
   2734 		return -ENOTTY;
   2735 	}
   2736 }
   2737 
   2738 static const struct file_operations nvme_dev_fops = {
   2739 	.owner		= THIS_MODULE,
   2740 	.open		= nvme_dev_open,
   2741 	.unlocked_ioctl	= nvme_dev_ioctl,
   2742 	.compat_ioctl	= nvme_dev_ioctl,
   2743 };
   2744 
   2745 static ssize_t nvme_sysfs_reset(struct device *dev,
   2746 				struct device_attribute *attr, const char *buf,
   2747 				size_t count)
   2748 {
   2749 	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
   2750 	int ret;
   2751 
   2752 	ret = nvme_reset_ctrl_sync(ctrl);
   2753 	if (ret < 0)
   2754 		return ret;
   2755 	return count;
   2756 }
   2757 static DEVICE_ATTR(reset_controller, S_IWUSR, NULL, nvme_sysfs_reset);
   2758 
   2759 static ssize_t nvme_sysfs_rescan(struct device *dev,
   2760 				struct device_attribute *attr, const char *buf,
   2761 				size_t count)
   2762 {
   2763 	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
   2764 
   2765 	nvme_queue_scan(ctrl);
   2766 	return count;
   2767 }
   2768 static DEVICE_ATTR(rescan_controller, S_IWUSR, NULL, nvme_sysfs_rescan);
   2769 
   2770 static inline struct nvme_ns_head *dev_to_ns_head(struct device *dev)
   2771 {
   2772 	struct gendisk *disk = dev_to_disk(dev);
   2773 
   2774 	if (disk->fops == &nvme_fops)
   2775 		return nvme_get_ns_from_dev(dev)->head;
   2776 	else
   2777 		return disk->private_data;
   2778 }
   2779 
   2780 static ssize_t wwid_show(struct device *dev, struct device_attribute *attr,
   2781 		char *buf)
   2782 {
   2783 	struct nvme_ns_head *head = dev_to_ns_head(dev);
   2784 	struct nvme_ns_ids *ids = &head->ids;
   2785 	struct nvme_subsystem *subsys = head->subsys;
   2786 	int serial_len = sizeof(subsys->serial);
   2787 	int model_len = sizeof(subsys->model);
   2788 
   2789 	if (!uuid_is_null(&ids->uuid))
   2790 		return sprintf(buf, "uuid.%pU\n", &ids->uuid);
   2791 
   2792 	if (memchr_inv(ids->nguid, 0, sizeof(ids->nguid)))
   2793 		return sprintf(buf, "eui.%16phN\n", ids->nguid);
   2794 
   2795 	if (memchr_inv(ids->eui64, 0, sizeof(ids->eui64)))
   2796 		return sprintf(buf, "eui.%8phN\n", ids->eui64);
   2797 
   2798 	while (serial_len > 0 && (subsys->serial[serial_len - 1] == ' ' ||
   2799 				  subsys->serial[serial_len - 1] == '\0'))
   2800 		serial_len--;
   2801 	while (model_len > 0 && (subsys->model[model_len - 1] == ' ' ||
   2802 				 subsys->model[model_len - 1] == '\0'))
   2803 		model_len--;
   2804 
   2805 	return sprintf(buf, "nvme.%04x-%*phN-%*phN-%08x\n", subsys->vendor_id,
   2806 		serial_len, subsys->serial, model_len, subsys->model,
   2807 		head->ns_id);
   2808 }
   2809 static DEVICE_ATTR_RO(wwid);
   2810 
   2811 static ssize_t nguid_show(struct device *dev, struct device_attribute *attr,
   2812 		char *buf)
   2813 {
   2814 	return sprintf(buf, "%pU\n", dev_to_ns_head(dev)->ids.nguid);
   2815 }
   2816 static DEVICE_ATTR_RO(nguid);
   2817 
   2818 static ssize_t uuid_show(struct device *dev, struct device_attribute *attr,
   2819 		char *buf)
   2820 {
   2821 	struct nvme_ns_ids *ids = &dev_to_ns_head(dev)->ids;
   2822 
   2823 	/* For backward compatibility expose the NGUID to userspace if
   2824 	 * we have no UUID set
   2825 	 */
   2826 	if (uuid_is_null(&ids->uuid)) {
   2827 		printk_ratelimited(KERN_WARNING
   2828 				   "No UUID available providing old NGUID\n");
   2829 		return sprintf(buf, "%pU\n", ids->nguid);
   2830 	}
   2831 	return sprintf(buf, "%pU\n", &ids->uuid);
   2832 }
   2833 static DEVICE_ATTR_RO(uuid);
   2834 
   2835 static ssize_t eui_show(struct device *dev, struct device_attribute *attr,
   2836 		char *buf)
   2837 {
   2838 	return sprintf(buf, "%8ph\n", dev_to_ns_head(dev)->ids.eui64);
   2839 }
   2840 static DEVICE_ATTR_RO(eui);
   2841 
   2842 static ssize_t nsid_show(struct device *dev, struct device_attribute *attr,
   2843 		char *buf)
   2844 {
   2845 	return sprintf(buf, "%d\n", dev_to_ns_head(dev)->ns_id);
   2846 }
   2847 static DEVICE_ATTR_RO(nsid);
   2848 
   2849 static struct attribute *nvme_ns_id_attrs[] = {
   2850 	&dev_attr_wwid.attr,
   2851 	&dev_attr_uuid.attr,
   2852 	&dev_attr_nguid.attr,
   2853 	&dev_attr_eui.attr,
   2854 	&dev_attr_nsid.attr,
   2855 #ifdef CONFIG_NVME_MULTIPATH
   2856 	&dev_attr_ana_grpid.attr,
   2857 	&dev_attr_ana_state.attr,
   2858 #endif
   2859 	NULL,
   2860 };
   2861 
   2862 static umode_t nvme_ns_id_attrs_are_visible(struct kobject *kobj,
   2863 		struct attribute *a, int n)
   2864 {
   2865 	struct device *dev = container_of(kobj, struct device, kobj);
   2866 	struct nvme_ns_ids *ids = &dev_to_ns_head(dev)->ids;
   2867 
   2868 	if (a == &dev_attr_uuid.attr) {
   2869 		if (uuid_is_null(&ids->uuid) &&
   2870 		    !memchr_inv(ids->nguid, 0, sizeof(ids->nguid)))
   2871 			return 0;
   2872 	}
   2873 	if (a == &dev_attr_nguid.attr) {
   2874 		if (!memchr_inv(ids->nguid, 0, sizeof(ids->nguid)))
   2875 			return 0;
   2876 	}
   2877 	if (a == &dev_attr_eui.attr) {
   2878 		if (!memchr_inv(ids->eui64, 0, sizeof(ids->eui64)))
   2879 			return 0;
   2880 	}
   2881 #ifdef CONFIG_NVME_MULTIPATH
   2882 	if (a == &dev_attr_ana_grpid.attr || a == &dev_attr_ana_state.attr) {
   2883 		if (dev_to_disk(dev)->fops != &nvme_fops) /* per-path attr */
   2884 			return 0;
   2885 		if (!nvme_ctrl_use_ana(nvme_get_ns_from_dev(dev)->ctrl))
   2886 			return 0;
   2887 	}
   2888 #endif
   2889 	return a->mode;
   2890 }
   2891 
   2892 static const struct attribute_group nvme_ns_id_attr_group = {
   2893 	.attrs		= nvme_ns_id_attrs,
   2894 	.is_visible	= nvme_ns_id_attrs_are_visible,
   2895 };
   2896 
   2897 const struct attribute_group *nvme_ns_id_attr_groups[] = {
   2898 	&nvme_ns_id_attr_group,
   2899 #ifdef CONFIG_NVM
   2900 	&nvme_nvm_attr_group,
   2901 #endif
   2902 	NULL,
   2903 };
   2904 
   2905 #define nvme_show_str_function(field)						\
   2906 static ssize_t  field##_show(struct device *dev,				\
   2907 			    struct device_attribute *attr, char *buf)		\
   2908 {										\
   2909         struct nvme_ctrl *ctrl = dev_get_drvdata(dev);				\
   2910         return sprintf(buf, "%.*s\n",						\
   2911 		(int)sizeof(ctrl->subsys->field), ctrl->subsys->field);		\
   2912 }										\
   2913 static DEVICE_ATTR(field, S_IRUGO, field##_show, NULL);
   2914 
   2915 nvme_show_str_function(model);
   2916 nvme_show_str_function(serial);
   2917 nvme_show_str_function(firmware_rev);
   2918 
   2919 #define nvme_show_int_function(field)						\
   2920 static ssize_t  field##_show(struct device *dev,				\
   2921 			    struct device_attribute *attr, char *buf)		\
   2922 {										\
   2923         struct nvme_ctrl *ctrl = dev_get_drvdata(dev);				\
   2924         return sprintf(buf, "%d\n", ctrl->field);	\
   2925 }										\
   2926 static DEVICE_ATTR(field, S_IRUGO, field##_show, NULL);
   2927 
   2928 nvme_show_int_function(cntlid);
   2929 nvme_show_int_function(numa_node);
   2930 
   2931 static ssize_t nvme_sysfs_delete(struct device *dev,
   2932 				struct device_attribute *attr, const char *buf,
   2933 				size_t count)
   2934 {
   2935 	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
   2936 
   2937 	if (device_remove_file_self(dev, attr))
   2938 		nvme_delete_ctrl_sync(ctrl);
   2939 	return count;
   2940 }
   2941 static DEVICE_ATTR(delete_controller, S_IWUSR, NULL, nvme_sysfs_delete);
   2942 
   2943 static ssize_t nvme_sysfs_show_transport(struct device *dev,
   2944 					 struct device_attribute *attr,
   2945 					 char *buf)
   2946 {
   2947 	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
   2948 
   2949 	return snprintf(buf, PAGE_SIZE, "%s\n", ctrl->ops->name);
   2950 }
   2951 static DEVICE_ATTR(transport, S_IRUGO, nvme_sysfs_show_transport, NULL);
   2952 
   2953 static ssize_t nvme_sysfs_show_state(struct device *dev,
   2954 				     struct device_attribute *attr,
   2955 				     char *buf)
   2956 {
   2957 	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
   2958 	static const char *const state_name[] = {
   2959 		[NVME_CTRL_NEW]		= "new",
   2960 		[NVME_CTRL_LIVE]	= "live",
   2961 		[NVME_CTRL_ADMIN_ONLY]	= "only-admin",
   2962 		[NVME_CTRL_RESETTING]	= "resetting",
   2963 		[NVME_CTRL_CONNECTING]	= "connecting",
   2964 		[NVME_CTRL_DELETING]	= "deleting",
   2965 		[NVME_CTRL_DEAD]	= "dead",
   2966 	};
   2967 
   2968 	if ((unsigned)ctrl->state < ARRAY_SIZE(state_name) &&
   2969 	    state_name[ctrl->state])
   2970 		return sprintf(buf, "%s\n", state_name[ctrl->state]);
   2971 
   2972 	return sprintf(buf, "unknown state\n");
   2973 }
   2974 
   2975 static DEVICE_ATTR(state, S_IRUGO, nvme_sysfs_show_state, NULL);
   2976 
   2977 static ssize_t nvme_sysfs_show_subsysnqn(struct device *dev,
   2978 					 struct device_attribute *attr,
   2979 					 char *buf)
   2980 {
   2981 	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
   2982 
   2983 	return snprintf(buf, PAGE_SIZE, "%s\n", ctrl->subsys->subnqn);
   2984 }
   2985 static DEVICE_ATTR(subsysnqn, S_IRUGO, nvme_sysfs_show_subsysnqn, NULL);
   2986 
   2987 static ssize_t nvme_sysfs_show_address(struct device *dev,
   2988 					 struct device_attribute *attr,
   2989 					 char *buf)
   2990 {
   2991 	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
   2992 
   2993 	return ctrl->ops->get_address(ctrl, buf, PAGE_SIZE);
   2994 }
   2995 static DEVICE_ATTR(address, S_IRUGO, nvme_sysfs_show_address, NULL);
   2996 
   2997 static struct attribute *nvme_dev_attrs[] = {
   2998 	&dev_attr_reset_controller.attr,
   2999 	&dev_attr_rescan_controller.attr,
   3000 	&dev_attr_model.attr,
   3001 	&dev_attr_serial.attr,
   3002 	&dev_attr_firmware_rev.attr,
   3003 	&dev_attr_cntlid.attr,
   3004 	&dev_attr_delete_controller.attr,
   3005 	&dev_attr_transport.attr,
   3006 	&dev_attr_subsysnqn.attr,
   3007 	&dev_attr_address.attr,
   3008 	&dev_attr_state.attr,
   3009 	&dev_attr_numa_node.attr,
   3010 	NULL
   3011 };
   3012 
   3013 static umode_t nvme_dev_attrs_are_visible(struct kobject *kobj,
   3014 		struct attribute *a, int n)
   3015 {
   3016 	struct device *dev = container_of(kobj, struct device, kobj);
   3017 	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
   3018 
   3019 	if (a == &dev_attr_delete_controller.attr && !ctrl->ops->delete_ctrl)
   3020 		return 0;
   3021 	if (a == &dev_attr_address.attr && !ctrl->ops->get_address)
   3022 		return 0;
   3023 
   3024 	return a->mode;
   3025 }
   3026 
   3027 static struct attribute_group nvme_dev_attrs_group = {
   3028 	.attrs		= nvme_dev_attrs,
   3029 	.is_visible	= nvme_dev_attrs_are_visible,
   3030 };
   3031 
   3032 static const struct attribute_group *nvme_dev_attr_groups[] = {
   3033 	&nvme_dev_attrs_group,
   3034 	NULL,
   3035 };
   3036 
   3037 static struct nvme_ns_head *__nvme_find_ns_head(struct nvme_subsystem *subsys,
   3038 		unsigned nsid)
   3039 {
   3040 	struct nvme_ns_head *h;
   3041 
   3042 	lockdep_assert_held(&subsys->lock);
   3043 
   3044 	list_for_each_entry(h, &subsys->nsheads, entry) {
   3045 		if (h->ns_id == nsid && kref_get_unless_zero(&h->ref))
   3046 			return h;
   3047 	}
   3048 
   3049 	return NULL;
   3050 }
   3051 
   3052 static int __nvme_check_ids(struct nvme_subsystem *subsys,
   3053 		struct nvme_ns_head *new)
   3054 {
   3055 	struct nvme_ns_head *h;
   3056 
   3057 	lockdep_assert_held(&subsys->lock);
   3058 
   3059 	list_for_each_entry(h, &subsys->nsheads, entry) {
   3060 		if (nvme_ns_ids_valid(&new->ids) &&
   3061 		    !list_empty(&h->list) &&
   3062 		    nvme_ns_ids_equal(&new->ids, &h->ids))
   3063 			return -EINVAL;
   3064 	}
   3065 
   3066 	return 0;
   3067 }
   3068 
   3069 static struct nvme_ns_head *nvme_alloc_ns_head(struct nvme_ctrl *ctrl,
   3070 		unsigned nsid, struct nvme_id_ns *id)
   3071 {
   3072 	struct nvme_ns_head *head;
   3073 	size_t size = sizeof(*head);
   3074 	int ret = -ENOMEM;
   3075 
   3076 #ifdef CONFIG_NVME_MULTIPATH
   3077 	size += num_possible_nodes() * sizeof(struct nvme_ns *);
   3078 #endif
   3079 
   3080 	head = kzalloc(size, GFP_KERNEL);
   3081 	if (!head)
   3082 		goto out;
   3083 	ret = ida_simple_get(&ctrl->subsys->ns_ida, 1, 0, GFP_KERNEL);
   3084 	if (ret < 0)
   3085 		goto out_free_head;
   3086 	head->instance = ret;
   3087 	INIT_LIST_HEAD(&head->list);
   3088 	ret = init_srcu_struct(&head->srcu);
   3089 	if (ret)
   3090 		goto out_ida_remove;
   3091 	head->subsys = ctrl->subsys;
   3092 	head->ns_id = nsid;
   3093 	kref_init(&head->ref);
   3094 
   3095 	nvme_report_ns_ids(ctrl, nsid, id, &head->ids);
   3096 
   3097 	ret = __nvme_check_ids(ctrl->subsys, head);
   3098 	if (ret) {
   3099 		dev_err(ctrl->device,
   3100 			"duplicate IDs for nsid %d\n", nsid);
   3101 		goto out_cleanup_srcu;
   3102 	}
   3103 
   3104 	ret = nvme_mpath_alloc_disk(ctrl, head);
   3105 	if (ret)
   3106 		goto out_cleanup_srcu;
   3107 
   3108 	list_add_tail(&head->entry, &ctrl->subsys->nsheads);
   3109 
   3110 	kref_get(&ctrl->subsys->ref);
   3111 
   3112 	return head;
   3113 out_cleanup_srcu:
   3114 	cleanup_srcu_struct(&head->srcu);
   3115 out_ida_remove:
   3116 	ida_simple_remove(&ctrl->subsys->ns_ida, head->instance);
   3117 out_free_head:
   3118 	kfree(head);
   3119 out:
   3120 	return ERR_PTR(ret);
   3121 }
   3122 
   3123 static int nvme_init_ns_head(struct nvme_ns *ns, unsigned nsid,
   3124 		struct nvme_id_ns *id)
   3125 {
   3126 	struct nvme_ctrl *ctrl = ns->ctrl;
   3127 	bool is_shared = id->nmic & (1 << 0);
   3128 	struct nvme_ns_head *head = NULL;
   3129 	int ret = 0;
   3130 
   3131 	mutex_lock(&ctrl->subsys->lock);
   3132 	if (is_shared)
   3133 		head = __nvme_find_ns_head(ctrl->subsys, nsid);
   3134 	if (!head) {
   3135 		head = nvme_alloc_ns_head(ctrl, nsid, id);
   3136 		if (IS_ERR(head)) {
   3137 			ret = PTR_ERR(head);
   3138 			goto out_unlock;
   3139 		}
   3140 	} else {
   3141 		struct nvme_ns_ids ids;
   3142 
   3143 		nvme_report_ns_ids(ctrl, nsid, id, &ids);
   3144 		if (!nvme_ns_ids_equal(&head->ids, &ids)) {
   3145 			dev_err(ctrl->device,
   3146 				"IDs don't match for shared namespace %d\n",
   3147 					nsid);
   3148 			ret = -EINVAL;
   3149 			goto out_unlock;
   3150 		}
   3151 	}
   3152 
   3153 	list_add_tail(&ns->siblings, &head->list);
   3154 	ns->head = head;
   3155 
   3156 out_unlock:
   3157 	mutex_unlock(&ctrl->subsys->lock);
   3158 	return ret;
   3159 }
   3160 
   3161 static int ns_cmp(void *priv, struct list_head *a, struct list_head *b)
   3162 {
   3163 	struct nvme_ns *nsa = container_of(a, struct nvme_ns, list);
   3164 	struct nvme_ns *nsb = container_of(b, struct nvme_ns, list);
   3165 
   3166 	return nsa->head->ns_id - nsb->head->ns_id;
   3167 }
   3168 
   3169 static struct nvme_ns *nvme_find_get_ns(struct nvme_ctrl *ctrl, unsigned nsid)
   3170 {
   3171 	struct nvme_ns *ns, *ret = NULL;
   3172 
   3173 	down_read(&ctrl->namespaces_rwsem);
   3174 	list_for_each_entry(ns, &ctrl->namespaces, list) {
   3175 		if (ns->head->ns_id == nsid) {
   3176 			if (!kref_get_unless_zero(&ns->kref))
   3177 				continue;
   3178 			ret = ns;
   3179 			break;
   3180 		}
   3181 		if (ns->head->ns_id > nsid)
   3182 			break;
   3183 	}
   3184 	up_read(&ctrl->namespaces_rwsem);
   3185 	return ret;
   3186 }
   3187 
   3188 static int nvme_setup_streams_ns(struct nvme_ctrl *ctrl, struct nvme_ns *ns)
   3189 {
   3190 	struct streams_directive_params s;
   3191 	int ret;
   3192 
   3193 	if (!ctrl->nr_streams)
   3194 		return 0;
   3195 
   3196 	ret = nvme_get_stream_params(ctrl, &s, ns->head->ns_id);
   3197 	if (ret)
   3198 		return ret;
   3199 
   3200 	ns->sws = le32_to_cpu(s.sws);
   3201 	ns->sgs = le16_to_cpu(s.sgs);
   3202 
   3203 	if (ns->sws) {
   3204 		unsigned int bs = 1 << ns->lba_shift;
   3205 
   3206 		blk_queue_io_min(ns->queue, bs * ns->sws);
   3207 		if (ns->sgs)
   3208 			blk_queue_io_opt(ns->queue, bs * ns->sws * ns->sgs);
   3209 	}
   3210 
   3211 	return 0;
   3212 }
   3213 
   3214 static int nvme_alloc_ns(struct nvme_ctrl *ctrl, unsigned nsid)
   3215 {
   3216 	struct nvme_ns *ns;
   3217 	struct gendisk *disk;
   3218 	struct nvme_id_ns *id;
   3219 	char disk_name[DISK_NAME_LEN];
   3220 	int node = ctrl->numa_node, flags = GENHD_FL_EXT_DEVT, ret;
   3221 
   3222 	ns = kzalloc_node(sizeof(*ns), GFP_KERNEL, node);
   3223 	if (!ns)
   3224 		return -ENOMEM;
   3225 
   3226 	ns->queue = blk_mq_init_queue(ctrl->tagset);
   3227 	if (IS_ERR(ns->queue)) {
   3228 		ret = PTR_ERR(ns->queue);
   3229 		goto out_free_ns;
   3230 	}
   3231 
   3232 	blk_queue_flag_set(QUEUE_FLAG_NONROT, ns->queue);
   3233 	if (ctrl->ops->flags & NVME_F_PCI_P2PDMA)
   3234 		blk_queue_flag_set(QUEUE_FLAG_PCI_P2PDMA, ns->queue);
   3235 
   3236 	ns->queue->queuedata = ns;
   3237 	ns->ctrl = ctrl;
   3238 
   3239 	kref_init(&ns->kref);
   3240 	ns->lba_shift = 9; /* set to a default value for 512 until disk is validated */
   3241 
   3242 	blk_queue_logical_block_size(ns->queue, 1 << ns->lba_shift);
   3243 	nvme_set_queue_limits(ctrl, ns->queue);
   3244 
   3245 	id = nvme_identify_ns(ctrl, nsid);
   3246 	if (!id) {
   3247 		ret = -EIO;
   3248 		goto out_free_queue;
   3249 	}
   3250 
   3251 	if (id->ncap == 0) {
   3252 		ret = -EINVAL;
   3253 		goto out_free_id;
   3254 	}
   3255 
   3256 	ret = nvme_init_ns_head(ns, nsid, id);
   3257 	if (ret)
   3258 		goto out_free_id;
   3259 	nvme_setup_streams_ns(ctrl, ns);
   3260 	nvme_set_disk_name(disk_name, ns, ctrl, &flags);
   3261 
   3262 	disk = alloc_disk_node(0, node);
   3263 	if (!disk) {
   3264 		ret = -ENOMEM;
   3265 		goto out_unlink_ns;
   3266 	}
   3267 
   3268 	disk->fops = &nvme_fops;
   3269 	disk->private_data = ns;
   3270 	disk->queue = ns->queue;
   3271 	disk->flags = flags;
   3272 	memcpy(disk->disk_name, disk_name, DISK_NAME_LEN);
   3273 	ns->disk = disk;
   3274 
   3275 	__nvme_revalidate_disk(disk, id);
   3276 
   3277 	if ((ctrl->quirks & NVME_QUIRK_LIGHTNVM) && id->vs[0] == 0x1) {
   3278 		ret = nvme_nvm_register(ns, disk_name, node);
   3279 		if (ret) {
   3280 			dev_warn(ctrl->device, "LightNVM init failure\n");
   3281 			goto out_put_disk;
   3282 		}
   3283 	}
   3284 
   3285 	down_write(&ctrl->namespaces_rwsem);
   3286 	list_add_tail(&ns->list, &ctrl->namespaces);
   3287 	up_write(&ctrl->namespaces_rwsem);
   3288 
   3289 	nvme_get_ctrl(ctrl);
   3290 
   3291 	device_add_disk(ctrl->device, ns->disk, nvme_ns_id_attr_groups);
   3292 
   3293 	nvme_mpath_add_disk(ns, id);
   3294 	nvme_fault_inject_init(ns);
   3295 	kfree(id);
   3296 
   3297 	return 0;
   3298  out_put_disk:
   3299 	put_disk(ns->disk);
   3300  out_unlink_ns:
   3301 	mutex_lock(&ctrl->subsys->lock);
   3302 	list_del_rcu(&ns->siblings);
   3303 	mutex_unlock(&ctrl->subsys->lock);
   3304 	nvme_put_ns_head(ns->head);
   3305  out_free_id:
   3306 	kfree(id);
   3307  out_free_queue:
   3308 	blk_cleanup_queue(ns->queue);
   3309  out_free_ns:
   3310 	kfree(ns);
   3311 	return ret;
   3312 }
   3313 
   3314 static void nvme_ns_remove(struct nvme_ns *ns)
   3315 {
   3316 	if (test_and_set_bit(NVME_NS_REMOVING, &ns->flags))
   3317 		return;
   3318 
   3319 	nvme_fault_inject_fini(ns);
   3320 	if (ns->disk && ns->disk->flags & GENHD_FL_UP) {
   3321 		del_gendisk(ns->disk);
   3322 		blk_cleanup_queue(ns->queue);
   3323 		if (blk_get_integrity(ns->disk))
   3324 			blk_integrity_unregister(ns->disk);
   3325 	}
   3326 
   3327 	mutex_lock(&ns->ctrl->subsys->lock);
   3328 	list_del_rcu(&ns->siblings);
   3329 	nvme_mpath_clear_current_path(ns);
   3330 	mutex_unlock(&ns->ctrl->subsys->lock);
   3331 
   3332 	down_write(&ns->ctrl->namespaces_rwsem);
   3333 	list_del_init(&ns->list);
   3334 	up_write(&ns->ctrl->namespaces_rwsem);
   3335 
   3336 	synchronize_srcu(&ns->head->srcu);
   3337 	nvme_mpath_check_last_path(ns);
   3338 	nvme_put_ns(ns);
   3339 }
   3340 
   3341 static void nvme_validate_ns(struct nvme_ctrl *ctrl, unsigned nsid)
   3342 {
   3343 	struct nvme_ns *ns;
   3344 
   3345 	ns = nvme_find_get_ns(ctrl, nsid);
   3346 	if (ns) {
   3347 		if (ns->disk && revalidate_disk(ns->disk))
   3348 			nvme_ns_remove(ns);
   3349 		nvme_put_ns(ns);
   3350 	} else
   3351 		nvme_alloc_ns(ctrl, nsid);
   3352 }
   3353 
   3354 static void nvme_remove_invalid_namespaces(struct nvme_ctrl *ctrl,
   3355 					unsigned nsid)
   3356 {
   3357 	struct nvme_ns *ns, *next;
   3358 	LIST_HEAD(rm_list);
   3359 
   3360 	down_write(&ctrl->namespaces_rwsem);
   3361 	list_for_each_entry_safe(ns, next, &ctrl->namespaces, list) {
   3362 		if (ns->head->ns_id > nsid || test_bit(NVME_NS_DEAD, &ns->flags))
   3363 			list_move_tail(&ns->list, &rm_list);
   3364 	}
   3365 	up_write(&ctrl->namespaces_rwsem);
   3366 
   3367 	list_for_each_entry_safe(ns, next, &rm_list, list)
   3368 		nvme_ns_remove(ns);
   3369 
   3370 }
   3371 
   3372 static int nvme_scan_ns_list(struct nvme_ctrl *ctrl, unsigned nn)
   3373 {
   3374 	struct nvme_ns *ns;
   3375 	__le32 *ns_list;
   3376 	unsigned i, j, nsid, prev = 0, num_lists = DIV_ROUND_UP(nn, 1024);
   3377 	int ret = 0;
   3378 
   3379 	ns_list = kzalloc(NVME_IDENTIFY_DATA_SIZE, GFP_KERNEL);
   3380 	if (!ns_list)
   3381 		return -ENOMEM;
   3382 
   3383 	for (i = 0; i < num_lists; i++) {
   3384 		ret = nvme_identify_ns_list(ctrl, prev, ns_list);
   3385 		if (ret)
   3386 			goto free;
   3387 
   3388 		for (j = 0; j < min(nn, 1024U); j++) {
   3389 			nsid = le32_to_cpu(ns_list[j]);
   3390 			if (!nsid)
   3391 				goto out;
   3392 
   3393 			nvme_validate_ns(ctrl, nsid);
   3394 
   3395 			while (++prev < nsid) {
   3396 				ns = nvme_find_get_ns(ctrl, prev);
   3397 				if (ns) {
   3398 					nvme_ns_remove(ns);
   3399 					nvme_put_ns(ns);
   3400 				}
   3401 			}
   3402 		}
   3403 		nn -= j;
   3404 	}
   3405  out:
   3406 	nvme_remove_invalid_namespaces(ctrl, prev);
   3407  free:
   3408 	kfree(ns_list);
   3409 	return ret;
   3410 }
   3411 
   3412 static void nvme_scan_ns_sequential(struct nvme_ctrl *ctrl, unsigned nn)
   3413 {
   3414 	unsigned i;
   3415 
   3416 	for (i = 1; i <= nn; i++)
   3417 		nvme_validate_ns(ctrl, i);
   3418 
   3419 	nvme_remove_invalid_namespaces(ctrl, nn);
   3420 }
   3421 
   3422 static void nvme_clear_changed_ns_log(struct nvme_ctrl *ctrl)
   3423 {
   3424 	size_t log_size = NVME_MAX_CHANGED_NAMESPACES * sizeof(__le32);
   3425 	__le32 *log;
   3426 	int error;
   3427 
   3428 	log = kzalloc(log_size, GFP_KERNEL);
   3429 	if (!log)
   3430 		return;
   3431 
   3432 	/*
   3433 	 * We need to read the log to clear the AEN, but we don't want to rely
   3434 	 * on it for the changed namespace information as userspace could have
   3435 	 * raced with us in reading the log page, which could cause us to miss
   3436 	 * updates.
   3437 	 */
   3438 	error = nvme_get_log(ctrl, NVME_NSID_ALL, NVME_LOG_CHANGED_NS, 0, log,
   3439 			log_size, 0);
   3440 	if (error)
   3441 		dev_warn(ctrl->device,
   3442 			"reading changed ns log failed: %d\n", error);
   3443 
   3444 	kfree(log);
   3445 }
   3446 
   3447 static void nvme_scan_work(struct work_struct *work)
   3448 {
   3449 	struct nvme_ctrl *ctrl =
   3450 		container_of(work, struct nvme_ctrl, scan_work);
   3451 	struct nvme_id_ctrl *id;
   3452 	unsigned nn;
   3453 
   3454 	if (ctrl->state != NVME_CTRL_LIVE)
   3455 		return;
   3456 
   3457 	WARN_ON_ONCE(!ctrl->tagset);
   3458 
   3459 	if (test_and_clear_bit(NVME_AER_NOTICE_NS_CHANGED, &ctrl->events)) {
   3460 		dev_info(ctrl->device, "rescanning namespaces.\n");
   3461 		nvme_clear_changed_ns_log(ctrl);
   3462 	}
   3463 
   3464 	if (nvme_identify_ctrl(ctrl, &id))
   3465 		return;
   3466 
   3467 	mutex_lock(&ctrl->scan_lock);
   3468 	nn = le32_to_cpu(id->nn);
   3469 	if (ctrl->vs >= NVME_VS(1, 1, 0) &&
   3470 	    !(ctrl->quirks & NVME_QUIRK_IDENTIFY_CNS)) {
   3471 		if (!nvme_scan_ns_list(ctrl, nn))
   3472 			goto out_free_id;
   3473 	}
   3474 	nvme_scan_ns_sequential(ctrl, nn);
   3475 out_free_id:
   3476 	mutex_unlock(&ctrl->scan_lock);
   3477 	kfree(id);
   3478 	down_write(&ctrl->namespaces_rwsem);
   3479 	list_sort(NULL, &ctrl->namespaces, ns_cmp);
   3480 	up_write(&ctrl->namespaces_rwsem);
   3481 }
   3482 
   3483 /*
   3484  * This function iterates the namespace list unlocked to allow recovery from
   3485  * controller failure. It is up to the caller to ensure the namespace list is
   3486  * not modified by scan work while this function is executing.
   3487  */
   3488 void nvme_remove_namespaces(struct nvme_ctrl *ctrl)
   3489 {
   3490 	struct nvme_ns *ns, *next;
   3491 	LIST_HEAD(ns_list);
   3492 
   3493 	/* prevent racing with ns scanning */
   3494 	flush_work(&ctrl->scan_work);
   3495 
   3496 	/*
   3497 	 * The dead states indicates the controller was not gracefully
   3498 	 * disconnected. In that case, we won't be able to flush any data while
   3499 	 * removing the namespaces' disks; fail all the queues now to avoid
   3500 	 * potentially having to clean up the failed sync later.
   3501 	 */
   3502 	if (ctrl->state == NVME_CTRL_DEAD)
   3503 		nvme_kill_queues(ctrl);
   3504 
   3505 	down_write(&ctrl->namespaces_rwsem);
   3506 	list_splice_init(&ctrl->namespaces, &ns_list);
   3507 	up_write(&ctrl->namespaces_rwsem);
   3508 
   3509 	list_for_each_entry_safe(ns, next, &ns_list, list)
   3510 		nvme_ns_remove(ns);
   3511 }
   3512 EXPORT_SYMBOL_GPL(nvme_remove_namespaces);
   3513 
   3514 static void nvme_aen_uevent(struct nvme_ctrl *ctrl)
   3515 {
   3516 	char *envp[2] = { NULL, NULL };
   3517 	u32 aen_result = ctrl->aen_result;
   3518 
   3519 	ctrl->aen_result = 0;
   3520 	if (!aen_result)
   3521 		return;
   3522 
   3523 	envp[0] = kasprintf(GFP_KERNEL, "NVME_AEN=%#08x", aen_result);
   3524 	if (!envp[0])
   3525 		return;
   3526 	kobject_uevent_env(&ctrl->device->kobj, KOBJ_CHANGE, envp);
   3527 	kfree(envp[0]);
   3528 }
   3529 
   3530 static void nvme_async_event_work(struct work_struct *work)
   3531 {
   3532 	struct nvme_ctrl *ctrl =
   3533 		container_of(work, struct nvme_ctrl, async_event_work);
   3534 
   3535 	nvme_aen_uevent(ctrl);
   3536 	ctrl->ops->submit_async_event(ctrl);
   3537 }
   3538 
   3539 static bool nvme_ctrl_pp_status(struct nvme_ctrl *ctrl)
   3540 {
   3541 
   3542 	u32 csts;
   3543 
   3544 	if (ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &csts))
   3545 		return false;
   3546 
   3547 	if (csts == ~0)
   3548 		return false;
   3549 
   3550 	return ((ctrl->ctrl_config & NVME_CC_ENABLE) && (csts & NVME_CSTS_PP));
   3551 }
   3552 
   3553 static void nvme_get_fw_slot_info(struct nvme_ctrl *ctrl)
   3554 {
   3555 	struct nvme_fw_slot_info_log *log;
   3556 
   3557 	log = kmalloc(sizeof(*log), GFP_KERNEL);
   3558 	if (!log)
   3559 		return;
   3560 
   3561 	if (nvme_get_log(ctrl, NVME_NSID_ALL, 0, NVME_LOG_FW_SLOT, log,
   3562 			sizeof(*log), 0))
   3563 		dev_warn(ctrl->device, "Get FW SLOT INFO log error\n");
   3564 	kfree(log);
   3565 }
   3566 
   3567 static void nvme_fw_act_work(struct work_struct *work)
   3568 {
   3569 	struct nvme_ctrl *ctrl = container_of(work,
   3570 				struct nvme_ctrl, fw_act_work);
   3571 	unsigned long fw_act_timeout;
   3572 
   3573 	if (ctrl->mtfa)
   3574 		fw_act_timeout = jiffies +
   3575 				msecs_to_jiffies(ctrl->mtfa * 100);
   3576 	else
   3577 		fw_act_timeout = jiffies +
   3578 				msecs_to_jiffies(admin_timeout * 1000);
   3579 
   3580 	nvme_stop_queues(ctrl);
   3581 	while (nvme_ctrl_pp_status(ctrl)) {
   3582 		if (time_after(jiffies, fw_act_timeout)) {
   3583 			dev_warn(ctrl->device,
   3584 				"Fw activation timeout, reset controller\n");
   3585 			nvme_reset_ctrl(ctrl);
   3586 			break;
   3587 		}
   3588 		msleep(100);
   3589 	}
   3590 
   3591 	if (ctrl->state != NVME_CTRL_LIVE)
   3592 		return;
   3593 
   3594 	nvme_start_queues(ctrl);
   3595 	/* read FW slot information to clear the AER */
   3596 	nvme_get_fw_slot_info(ctrl);
   3597 }
   3598 
   3599 static void nvme_handle_aen_notice(struct nvme_ctrl *ctrl, u32 result)
   3600 {
   3601 	u32 aer_notice_type = (result & 0xff00) >> 8;
   3602 
   3603 	switch (aer_notice_type) {
   3604 	case NVME_AER_NOTICE_NS_CHANGED:
   3605 		trace_nvme_async_event(ctrl, aer_notice_type);
   3606 		set_bit(NVME_AER_NOTICE_NS_CHANGED, &ctrl->events);
   3607 		nvme_queue_scan(ctrl);
   3608 		break;
   3609 	case NVME_AER_NOTICE_FW_ACT_STARTING:
   3610 		trace_nvme_async_event(ctrl, aer_notice_type);
   3611 		queue_work(nvme_wq, &ctrl->fw_act_work);
   3612 		break;
   3613 #ifdef CONFIG_NVME_MULTIPATH
   3614 	case NVME_AER_NOTICE_ANA:
   3615 		trace_nvme_async_event(ctrl, aer_notice_type);
   3616 		if (!ctrl->ana_log_buf)
   3617 			break;
   3618 		queue_work(nvme_wq, &ctrl->ana_work);
   3619 		break;
   3620 #endif
   3621 	default:
   3622 		dev_warn(ctrl->device, "async event result %08x\n", result);
   3623 	}
   3624 }
   3625 
   3626 void nvme_complete_async_event(struct nvme_ctrl *ctrl, __le16 status,
   3627 		volatile union nvme_result *res)
   3628 {
   3629 	u32 result = le32_to_cpu(res->u32);
   3630 	u32 aer_type = result & 0x07;
   3631 
   3632 	if (le16_to_cpu(status) >> 1 != NVME_SC_SUCCESS)
   3633 		return;
   3634 
   3635 	switch (aer_type) {
   3636 	case NVME_AER_NOTICE:
   3637 		nvme_handle_aen_notice(ctrl, result);
   3638 		break;
   3639 	case NVME_AER_ERROR:
   3640 	case NVME_AER_SMART:
   3641 	case NVME_AER_CSS:
   3642 	case NVME_AER_VS:
   3643 		trace_nvme_async_event(ctrl, aer_type);
   3644 		ctrl->aen_result = result;
   3645 		break;
   3646 	default:
   3647 		break;
   3648 	}
   3649 	queue_work(nvme_wq, &ctrl->async_event_work);
   3650 }
   3651 EXPORT_SYMBOL_GPL(nvme_complete_async_event);
   3652 
   3653 void nvme_stop_ctrl(struct nvme_ctrl *ctrl)
   3654 {
   3655 	nvme_mpath_stop(ctrl);
   3656 	nvme_stop_keep_alive(ctrl);
   3657 	flush_work(&ctrl->async_event_work);
   3658 	cancel_work_sync(&ctrl->fw_act_work);
   3659 }
   3660 EXPORT_SYMBOL_GPL(nvme_stop_ctrl);
   3661 
   3662 void nvme_start_ctrl(struct nvme_ctrl *ctrl)
   3663 {
   3664 	if (ctrl->kato)
   3665 		nvme_start_keep_alive(ctrl);
   3666 
   3667 	if (ctrl->queue_count > 1) {
   3668 		nvme_queue_scan(ctrl);
   3669 		nvme_enable_aen(ctrl);
   3670 		queue_work(nvme_wq, &ctrl->async_event_work);
   3671 		nvme_start_queues(ctrl);
   3672 	}
   3673 }
   3674 EXPORT_SYMBOL_GPL(nvme_start_ctrl);
   3675 
   3676 void nvme_uninit_ctrl(struct nvme_ctrl *ctrl)
   3677 {
   3678 	cdev_device_del(&ctrl->cdev, ctrl->device);
   3679 }
   3680 EXPORT_SYMBOL_GPL(nvme_uninit_ctrl);
   3681 
   3682 static void nvme_free_ctrl(struct device *dev)
   3683 {
   3684 	struct nvme_ctrl *ctrl =
   3685 		container_of(dev, struct nvme_ctrl, ctrl_device);
   3686 	struct nvme_subsystem *subsys = ctrl->subsys;
   3687 
   3688 	ida_simple_remove(&nvme_instance_ida, ctrl->instance);
   3689 	kfree(ctrl->effects);
   3690 	nvme_mpath_uninit(ctrl);
   3691 	__free_page(ctrl->discard_page);
   3692 
   3693 	if (subsys) {
   3694 		mutex_lock(&subsys->lock);
   3695 		list_del(&ctrl->subsys_entry);
   3696 		mutex_unlock(&subsys->lock);
   3697 		sysfs_remove_link(&subsys->dev.kobj, dev_name(ctrl->device));
   3698 	}
   3699 
   3700 	ctrl->ops->free_ctrl(ctrl);
   3701 
   3702 	if (subsys)
   3703 		nvme_put_subsystem(subsys);
   3704 }
   3705 
   3706 /*
   3707  * Initialize a NVMe controller structures.  This needs to be called during
   3708  * earliest initialization so that we have the initialized structured around
   3709  * during probing.
   3710  */
   3711 int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
   3712 		const struct nvme_ctrl_ops *ops, unsigned long quirks)
   3713 {
   3714 	int ret;
   3715 
   3716 	ctrl->state = NVME_CTRL_NEW;
   3717 	spin_lock_init(&ctrl->lock);
   3718 	mutex_init(&ctrl->scan_lock);
   3719 	INIT_LIST_HEAD(&ctrl->namespaces);
   3720 	init_rwsem(&ctrl->namespaces_rwsem);
   3721 	ctrl->dev = dev;
   3722 	ctrl->ops = ops;
   3723 	ctrl->quirks = quirks;
   3724 	INIT_WORK(&ctrl->scan_work, nvme_scan_work);
   3725 	INIT_WORK(&ctrl->async_event_work, nvme_async_event_work);
   3726 	INIT_WORK(&ctrl->fw_act_work, nvme_fw_act_work);
   3727 	INIT_WORK(&ctrl->delete_work, nvme_delete_ctrl_work);
   3728 
   3729 	INIT_DELAYED_WORK(&ctrl->ka_work, nvme_keep_alive_work);
   3730 	memset(&ctrl->ka_cmd, 0, sizeof(ctrl->ka_cmd));
   3731 	ctrl->ka_cmd.common.opcode = nvme_admin_keep_alive;
   3732 
   3733 	BUILD_BUG_ON(NVME_DSM_MAX_RANGES * sizeof(struct nvme_dsm_range) >
   3734 			PAGE_SIZE);
   3735 	ctrl->discard_page = alloc_page(GFP_KERNEL);
   3736 	if (!ctrl->discard_page) {
   3737 		ret = -ENOMEM;
   3738 		goto out;
   3739 	}
   3740 
   3741 	ret = ida_simple_get(&nvme_instance_ida, 0, 0, GFP_KERNEL);
   3742 	if (ret < 0)
   3743 		goto out;
   3744 	ctrl->instance = ret;
   3745 
   3746 	device_initialize(&ctrl->ctrl_device);
   3747 	ctrl->device = &ctrl->ctrl_device;
   3748 	ctrl->device->devt = MKDEV(MAJOR(nvme_chr_devt), ctrl->instance);
   3749 	ctrl->device->class = nvme_class;
   3750 	ctrl->device->parent = ctrl->dev;
   3751 	ctrl->device->groups = nvme_dev_attr_groups;
   3752 	ctrl->device->release = nvme_free_ctrl;
   3753 	dev_set_drvdata(ctrl->device, ctrl);
   3754 	ret = dev_set_name(ctrl->device, "nvme%d", ctrl->instance);
   3755 	if (ret)
   3756 		goto out_release_instance;
   3757 
   3758 	cdev_init(&ctrl->cdev, &nvme_dev_fops);
   3759 	ctrl->cdev.owner = ops->module;
   3760 	ret = cdev_device_add(&ctrl->cdev, ctrl->device);
   3761 	if (ret)
   3762 		goto out_free_name;
   3763 
   3764 	/*
   3765 	 * Initialize latency tolerance controls.  The sysfs files won't
   3766 	 * be visible to userspace unless the device actually supports APST.
   3767 	 */
   3768 	ctrl->device->power.set_latency_tolerance = nvme_set_latency_tolerance;
   3769 	dev_pm_qos_update_user_latency_tolerance(ctrl->device,
   3770 		min(default_ps_max_latency_us, (unsigned long)S32_MAX));
   3771 
   3772 	return 0;
   3773 out_free_name:
   3774 	kfree_const(ctrl->device->kobj.name);
   3775 out_release_instance:
   3776 	ida_simple_remove(&nvme_instance_ida, ctrl->instance);
   3777 out:
   3778 	if (ctrl->discard_page)
   3779 		__free_page(ctrl->discard_page);
   3780 	return ret;
   3781 }
   3782 EXPORT_SYMBOL_GPL(nvme_init_ctrl);
   3783 
   3784 /**
   3785  * nvme_kill_queues(): Ends all namespace queues
   3786  * @ctrl: the dead controller that needs to end
   3787  *
   3788  * Call this function when the driver determines it is unable to get the
   3789  * controller in a state capable of servicing IO.
   3790  */
   3791 void nvme_kill_queues(struct nvme_ctrl *ctrl)
   3792 {
   3793 	struct nvme_ns *ns;
   3794 
   3795 	down_read(&ctrl->namespaces_rwsem);
   3796 
   3797 	/* Forcibly unquiesce queues to avoid blocking dispatch */
   3798 	if (ctrl->admin_q && !blk_queue_dying(ctrl->admin_q))
   3799 		blk_mq_unquiesce_queue(ctrl->admin_q);
   3800 
   3801 	list_for_each_entry(ns, &ctrl->namespaces, list)
   3802 		nvme_set_queue_dying(ns);
   3803 
   3804 	up_read(&ctrl->namespaces_rwsem);
   3805 }
   3806 EXPORT_SYMBOL_GPL(nvme_kill_queues);
   3807 
   3808 void nvme_unfreeze(struct nvme_ctrl *ctrl)
   3809 {
   3810 	struct nvme_ns *ns;
   3811 
   3812 	down_read(&ctrl->namespaces_rwsem);
   3813 	list_for_each_entry(ns, &ctrl->namespaces, list)
   3814 		blk_mq_unfreeze_queue(ns->queue);
   3815 	up_read(&ctrl->namespaces_rwsem);
   3816 }
   3817 EXPORT_SYMBOL_GPL(nvme_unfreeze);
   3818 
   3819 void nvme_wait_freeze_timeout(struct nvme_ctrl *ctrl, long timeout)
   3820 {
   3821 	struct nvme_ns *ns;
   3822 
   3823 	down_read(&ctrl->namespaces_rwsem);
   3824 	list_for_each_entry(ns, &ctrl->namespaces, list) {
   3825 		timeout = blk_mq_freeze_queue_wait_timeout(ns->queue, timeout);
   3826 		if (timeout <= 0)
   3827 			break;
   3828 	}
   3829 	up_read(&ctrl->namespaces_rwsem);
   3830 }
   3831 EXPORT_SYMBOL_GPL(nvme_wait_freeze_timeout);
   3832 
   3833 void nvme_wait_freeze(struct nvme_ctrl *ctrl)
   3834 {
   3835 	struct nvme_ns *ns;
   3836 
   3837 	down_read(&ctrl->namespaces_rwsem);
   3838 	list_for_each_entry(ns, &ctrl->namespaces, list)
   3839 		blk_mq_freeze_queue_wait(ns->queue);
   3840 	up_read(&ctrl->namespaces_rwsem);
   3841 }
   3842 EXPORT_SYMBOL_GPL(nvme_wait_freeze);
   3843 
   3844 void nvme_start_freeze(struct nvme_ctrl *ctrl)
   3845 {
   3846 	struct nvme_ns *ns;
   3847 
   3848 	down_read(&ctrl->namespaces_rwsem);
   3849 	list_for_each_entry(ns, &ctrl->namespaces, list)
   3850 		blk_freeze_queue_start(ns->queue);
   3851 	up_read(&ctrl->namespaces_rwsem);
   3852 }
   3853 EXPORT_SYMBOL_GPL(nvme_start_freeze);
   3854 
   3855 void nvme_stop_queues(struct nvme_ctrl *ctrl)
   3856 {
   3857 	struct nvme_ns *ns;
   3858 
   3859 	down_read(&ctrl->namespaces_rwsem);
   3860 	list_for_each_entry(ns, &ctrl->namespaces, list)
   3861 		blk_mq_quiesce_queue(ns->queue);
   3862 	up_read(&ctrl->namespaces_rwsem);
   3863 }
   3864 EXPORT_SYMBOL_GPL(nvme_stop_queues);
   3865 
   3866 void nvme_start_queues(struct nvme_ctrl *ctrl)
   3867 {
   3868 	struct nvme_ns *ns;
   3869 
   3870 	down_read(&ctrl->namespaces_rwsem);
   3871 	list_for_each_entry(ns, &ctrl->namespaces, list)
   3872 		blk_mq_unquiesce_queue(ns->queue);
   3873 	up_read(&ctrl->namespaces_rwsem);
   3874 }
   3875 EXPORT_SYMBOL_GPL(nvme_start_queues);
   3876 
   3877 int __init nvme_core_init(void)
   3878 {
   3879 	int result = -ENOMEM;
   3880 
   3881 	nvme_wq = alloc_workqueue("nvme-wq",
   3882 			WQ_UNBOUND | WQ_MEM_RECLAIM | WQ_SYSFS, 0);
   3883 	if (!nvme_wq)
   3884 		goto out;
   3885 
   3886 	nvme_reset_wq = alloc_workqueue("nvme-reset-wq",
   3887 			WQ_UNBOUND | WQ_MEM_RECLAIM | WQ_SYSFS, 0);
   3888 	if (!nvme_reset_wq)
   3889 		goto destroy_wq;
   3890 
   3891 	nvme_delete_wq = alloc_workqueue("nvme-delete-wq",
   3892 			WQ_UNBOUND | WQ_MEM_RECLAIM | WQ_SYSFS, 0);
   3893 	if (!nvme_delete_wq)
   3894 		goto destroy_reset_wq;
   3895 
   3896 	result = alloc_chrdev_region(&nvme_chr_devt, 0, NVME_MINORS, "nvme");
   3897 	if (result < 0)
   3898 		goto destroy_delete_wq;
   3899 
   3900 	nvme_class = class_create(THIS_MODULE, "nvme");
   3901 	if (IS_ERR(nvme_class)) {
   3902 		result = PTR_ERR(nvme_class);
   3903 		goto unregister_chrdev;
   3904 	}
   3905 
   3906 	nvme_subsys_class = class_create(THIS_MODULE, "nvme-subsystem");
   3907 	if (IS_ERR(nvme_subsys_class)) {
   3908 		result = PTR_ERR(nvme_subsys_class);
   3909 		goto destroy_class;
   3910 	}
   3911 	return 0;
   3912 
   3913 destroy_class:
   3914 	class_destroy(nvme_class);
   3915 unregister_chrdev:
   3916 	unregister_chrdev_region(nvme_chr_devt, NVME_MINORS);
   3917 destroy_delete_wq:
   3918 	destroy_workqueue(nvme_delete_wq);
   3919 destroy_reset_wq:
   3920 	destroy_workqueue(nvme_reset_wq);
   3921 destroy_wq:
   3922 	destroy_workqueue(nvme_wq);
   3923 out:
   3924 	return result;
   3925 }
   3926 
   3927 void __exit nvme_core_exit(void)
   3928 {
   3929 	ida_destroy(&nvme_subsystems_ida);
   3930 	class_destroy(nvme_subsys_class);
   3931 	class_destroy(nvme_class);
   3932 	unregister_chrdev_region(nvme_chr_devt, NVME_MINORS);
   3933 	destroy_workqueue(nvme_delete_wq);
   3934 	destroy_workqueue(nvme_reset_wq);
   3935 	destroy_workqueue(nvme_wq);
   3936 }
   3937 
   3938 MODULE_LICENSE("GPL");
   3939 MODULE_VERSION("1.0");
   3940 module_init(nvme_core_init);
   3941 module_exit(nvme_core_exit);