xref: /openbmc/linux/drivers/nvme/host/pci.c (revision c81545f991a6612d3bdab18a71b3487023ec6b69)
1 /*
2  * NVM Express device driver
3  * Copyright (c) 2011-2014, Intel Corporation.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms and conditions of the GNU General Public License,
7  * version 2, as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  */
14 
15 #include <linux/aer.h>
16 #include <linux/bitops.h>
17 #include <linux/blkdev.h>
18 #include <linux/blk-mq.h>
19 #include <linux/blk-mq-pci.h>
20 #include <linux/dmi.h>
21 #include <linux/init.h>
22 #include <linux/interrupt.h>
23 #include <linux/io.h>
24 #include <linux/mm.h>
25 #include <linux/module.h>
26 #include <linux/mutex.h>
27 #include <linux/pci.h>
28 #include <linux/poison.h>
29 #include <linux/t10-pi.h>
30 #include <linux/timer.h>
31 #include <linux/types.h>
32 #include <linux/io-64-nonatomic-lo-hi.h>
33 #include <asm/unaligned.h>
34 #include <linux/sed-opal.h>
35 
36 #include "nvme.h"
37 
38 #define NVME_Q_DEPTH		1024
39 #define SQ_SIZE(depth)		(depth * sizeof(struct nvme_command))
40 #define CQ_SIZE(depth)		(depth * sizeof(struct nvme_completion))
41 
42 /*
43  * We handle AEN commands ourselves and don't even let the
44  * block layer know about them.
45  */
46 #define NVME_AQ_BLKMQ_DEPTH	(NVME_AQ_DEPTH - NVME_NR_AERS)
47 
48 static int use_threaded_interrupts;
49 module_param(use_threaded_interrupts, int, 0);
50 
51 static bool use_cmb_sqes = true;
52 module_param(use_cmb_sqes, bool, 0644);
53 MODULE_PARM_DESC(use_cmb_sqes, "use controller's memory buffer for I/O SQes");
54 
55 static unsigned int max_host_mem_size_mb = 128;
56 module_param(max_host_mem_size_mb, uint, 0444);
57 MODULE_PARM_DESC(max_host_mem_size_mb,
58 	"Maximum Host Memory Buffer (HMB) size per controller (in MiB)");
59 
60 struct nvme_dev;
61 struct nvme_queue;
62 
63 static void nvme_process_cq(struct nvme_queue *nvmeq);
64 static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown);
65 
66 /*
67  * Represents an NVM Express device.  Each nvme_dev is a PCI function.
68  */
69 struct nvme_dev {
70 	struct nvme_queue **queues;
71 	struct blk_mq_tag_set tagset;
72 	struct blk_mq_tag_set admin_tagset;
73 	u32 __iomem *dbs;
74 	struct device *dev;
75 	struct dma_pool *prp_page_pool;
76 	struct dma_pool *prp_small_pool;
77 	unsigned online_queues;
78 	unsigned max_qid;
79 	int q_depth;
80 	u32 db_stride;
81 	void __iomem *bar;
82 	unsigned long bar_mapped_size;
83 	struct work_struct remove_work;
84 	struct mutex shutdown_lock;
85 	bool subsystem;
86 	void __iomem *cmb;
87 	dma_addr_t cmb_dma_addr;
88 	u64 cmb_size;
89 	u32 cmbsz;
90 	u32 cmbloc;
91 	struct nvme_ctrl ctrl;
92 	struct completion ioq_wait;
93 
94 	/* shadow doorbell buffer support: */
95 	u32 *dbbuf_dbs;
96 	dma_addr_t dbbuf_dbs_dma_addr;
97 	u32 *dbbuf_eis;
98 	dma_addr_t dbbuf_eis_dma_addr;
99 
100 	/* host memory buffer support: */
101 	u64 host_mem_size;
102 	u32 nr_host_mem_descs;
103 	struct nvme_host_mem_buf_desc *host_mem_descs;
104 	void **host_mem_desc_bufs;
105 };
106 
107 static inline unsigned int sq_idx(unsigned int qid, u32 stride)
108 {
109 	return qid * 2 * stride;
110 }
111 
112 static inline unsigned int cq_idx(unsigned int qid, u32 stride)
113 {
114 	return (qid * 2 + 1) * stride;
115 }
116 
117 static inline struct nvme_dev *to_nvme_dev(struct nvme_ctrl *ctrl)
118 {
119 	return container_of(ctrl, struct nvme_dev, ctrl);
120 }
121 
122 /*
123  * An NVM Express queue.  Each device has at least two (one for admin
124  * commands and one for I/O commands).
125  */
126 struct nvme_queue {
127 	struct device *q_dmadev;
128 	struct nvme_dev *dev;
129 	spinlock_t q_lock;
130 	struct nvme_command *sq_cmds;
131 	struct nvme_command __iomem *sq_cmds_io;
132 	volatile struct nvme_completion *cqes;
133 	struct blk_mq_tags **tags;
134 	dma_addr_t sq_dma_addr;
135 	dma_addr_t cq_dma_addr;
136 	u32 __iomem *q_db;
137 	u16 q_depth;
138 	s16 cq_vector;
139 	u16 sq_tail;
140 	u16 cq_head;
141 	u16 qid;
142 	u8 cq_phase;
143 	u8 cqe_seen;
144 	u32 *dbbuf_sq_db;
145 	u32 *dbbuf_cq_db;
146 	u32 *dbbuf_sq_ei;
147 	u32 *dbbuf_cq_ei;
148 };
149 
150 /*
151  * The nvme_iod describes the data in an I/O, including the list of PRP
152  * entries.  You can't see it in this data structure because C doesn't let
153  * me express that.  Use nvme_init_iod to ensure there's enough space
154  * allocated to store the PRP list.
155  */
156 struct nvme_iod {
157 	struct nvme_request req;
158 	struct nvme_queue *nvmeq;
159 	int aborted;
160 	int npages;		/* In the PRP list. 0 means small pool in use */
161 	int nents;		/* Used in scatterlist */
162 	int length;		/* Of data, in bytes */
163 	dma_addr_t first_dma;
164 	struct scatterlist meta_sg; /* metadata requires single contiguous buffer */
165 	struct scatterlist *sg;
166 	struct scatterlist inline_sg[0];
167 };
168 
169 /*
170  * Check we didin't inadvertently grow the command struct
171  */
172 static inline void _nvme_check_size(void)
173 {
174 	BUILD_BUG_ON(sizeof(struct nvme_rw_command) != 64);
175 	BUILD_BUG_ON(sizeof(struct nvme_create_cq) != 64);
176 	BUILD_BUG_ON(sizeof(struct nvme_create_sq) != 64);
177 	BUILD_BUG_ON(sizeof(struct nvme_delete_queue) != 64);
178 	BUILD_BUG_ON(sizeof(struct nvme_features) != 64);
179 	BUILD_BUG_ON(sizeof(struct nvme_format_cmd) != 64);
180 	BUILD_BUG_ON(sizeof(struct nvme_abort_cmd) != 64);
181 	BUILD_BUG_ON(sizeof(struct nvme_command) != 64);
182 	BUILD_BUG_ON(sizeof(struct nvme_id_ctrl) != NVME_IDENTIFY_DATA_SIZE);
183 	BUILD_BUG_ON(sizeof(struct nvme_id_ns) != NVME_IDENTIFY_DATA_SIZE);
184 	BUILD_BUG_ON(sizeof(struct nvme_lba_range_type) != 64);
185 	BUILD_BUG_ON(sizeof(struct nvme_smart_log) != 512);
186 	BUILD_BUG_ON(sizeof(struct nvme_dbbuf) != 64);
187 }
188 
189 static inline unsigned int nvme_dbbuf_size(u32 stride)
190 {
191 	return ((num_possible_cpus() + 1) * 8 * stride);
192 }
193 
194 static int nvme_dbbuf_dma_alloc(struct nvme_dev *dev)
195 {
196 	unsigned int mem_size = nvme_dbbuf_size(dev->db_stride);
197 
198 	if (dev->dbbuf_dbs)
199 		return 0;
200 
201 	dev->dbbuf_dbs = dma_alloc_coherent(dev->dev, mem_size,
202 					    &dev->dbbuf_dbs_dma_addr,
203 					    GFP_KERNEL);
204 	if (!dev->dbbuf_dbs)
205 		return -ENOMEM;
206 	dev->dbbuf_eis = dma_alloc_coherent(dev->dev, mem_size,
207 					    &dev->dbbuf_eis_dma_addr,
208 					    GFP_KERNEL);
209 	if (!dev->dbbuf_eis) {
210 		dma_free_coherent(dev->dev, mem_size,
211 				  dev->dbbuf_dbs, dev->dbbuf_dbs_dma_addr);
212 		dev->dbbuf_dbs = NULL;
213 		return -ENOMEM;
214 	}
215 
216 	return 0;
217 }
218 
219 static void nvme_dbbuf_dma_free(struct nvme_dev *dev)
220 {
221 	unsigned int mem_size = nvme_dbbuf_size(dev->db_stride);
222 
223 	if (dev->dbbuf_dbs) {
224 		dma_free_coherent(dev->dev, mem_size,
225 				  dev->dbbuf_dbs, dev->dbbuf_dbs_dma_addr);
226 		dev->dbbuf_dbs = NULL;
227 	}
228 	if (dev->dbbuf_eis) {
229 		dma_free_coherent(dev->dev, mem_size,
230 				  dev->dbbuf_eis, dev->dbbuf_eis_dma_addr);
231 		dev->dbbuf_eis = NULL;
232 	}
233 }
234 
235 static void nvme_dbbuf_init(struct nvme_dev *dev,
236 			    struct nvme_queue *nvmeq, int qid)
237 {
238 	if (!dev->dbbuf_dbs || !qid)
239 		return;
240 
241 	nvmeq->dbbuf_sq_db = &dev->dbbuf_dbs[sq_idx(qid, dev->db_stride)];
242 	nvmeq->dbbuf_cq_db = &dev->dbbuf_dbs[cq_idx(qid, dev->db_stride)];
243 	nvmeq->dbbuf_sq_ei = &dev->dbbuf_eis[sq_idx(qid, dev->db_stride)];
244 	nvmeq->dbbuf_cq_ei = &dev->dbbuf_eis[cq_idx(qid, dev->db_stride)];
245 }
246 
247 static void nvme_dbbuf_set(struct nvme_dev *dev)
248 {
249 	struct nvme_command c;
250 
251 	if (!dev->dbbuf_dbs)
252 		return;
253 
254 	memset(&c, 0, sizeof(c));
255 	c.dbbuf.opcode = nvme_admin_dbbuf;
256 	c.dbbuf.prp1 = cpu_to_le64(dev->dbbuf_dbs_dma_addr);
257 	c.dbbuf.prp2 = cpu_to_le64(dev->dbbuf_eis_dma_addr);
258 
259 	if (nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0)) {
260 		dev_warn(dev->ctrl.device, "unable to set dbbuf\n");
261 		/* Free memory and continue on */
262 		nvme_dbbuf_dma_free(dev);
263 	}
264 }
265 
266 static inline int nvme_dbbuf_need_event(u16 event_idx, u16 new_idx, u16 old)
267 {
268 	return (u16)(new_idx - event_idx - 1) < (u16)(new_idx - old);
269 }
270 
271 /* Update dbbuf and return true if an MMIO is required */
272 static bool nvme_dbbuf_update_and_check_event(u16 value, u32 *dbbuf_db,
273 					      volatile u32 *dbbuf_ei)
274 {
275 	if (dbbuf_db) {
276 		u16 old_value;
277 
278 		/*
279 		 * Ensure that the queue is written before updating
280 		 * the doorbell in memory
281 		 */
282 		wmb();
283 
284 		old_value = *dbbuf_db;
285 		*dbbuf_db = value;
286 
287 		if (!nvme_dbbuf_need_event(*dbbuf_ei, value, old_value))
288 			return false;
289 	}
290 
291 	return true;
292 }
293 
294 /*
295  * Max size of iod being embedded in the request payload
296  */
297 #define NVME_INT_PAGES		2
298 #define NVME_INT_BYTES(dev)	(NVME_INT_PAGES * (dev)->ctrl.page_size)
299 
300 /*
301  * Will slightly overestimate the number of pages needed.  This is OK
302  * as it only leads to a small amount of wasted memory for the lifetime of
303  * the I/O.
304  */
305 static int nvme_npages(unsigned size, struct nvme_dev *dev)
306 {
307 	unsigned nprps = DIV_ROUND_UP(size + dev->ctrl.page_size,
308 				      dev->ctrl.page_size);
309 	return DIV_ROUND_UP(8 * nprps, PAGE_SIZE - 8);
310 }
311 
312 static unsigned int nvme_iod_alloc_size(struct nvme_dev *dev,
313 		unsigned int size, unsigned int nseg)
314 {
315 	return sizeof(__le64 *) * nvme_npages(size, dev) +
316 			sizeof(struct scatterlist) * nseg;
317 }
318 
319 static unsigned int nvme_cmd_size(struct nvme_dev *dev)
320 {
321 	return sizeof(struct nvme_iod) +
322 		nvme_iod_alloc_size(dev, NVME_INT_BYTES(dev), NVME_INT_PAGES);
323 }
324 
325 static int nvme_admin_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
326 				unsigned int hctx_idx)
327 {
328 	struct nvme_dev *dev = data;
329 	struct nvme_queue *nvmeq = dev->queues[0];
330 
331 	WARN_ON(hctx_idx != 0);
332 	WARN_ON(dev->admin_tagset.tags[0] != hctx->tags);
333 	WARN_ON(nvmeq->tags);
334 
335 	hctx->driver_data = nvmeq;
336 	nvmeq->tags = &dev->admin_tagset.tags[0];
337 	return 0;
338 }
339 
340 static void nvme_admin_exit_hctx(struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx)
341 {
342 	struct nvme_queue *nvmeq = hctx->driver_data;
343 
344 	nvmeq->tags = NULL;
345 }
346 
347 static int nvme_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
348 			  unsigned int hctx_idx)
349 {
350 	struct nvme_dev *dev = data;
351 	struct nvme_queue *nvmeq = dev->queues[hctx_idx + 1];
352 
353 	if (!nvmeq->tags)
354 		nvmeq->tags = &dev->tagset.tags[hctx_idx];
355 
356 	WARN_ON(dev->tagset.tags[hctx_idx] != hctx->tags);
357 	hctx->driver_data = nvmeq;
358 	return 0;
359 }
360 
361 static int nvme_init_request(struct blk_mq_tag_set *set, struct request *req,
362 		unsigned int hctx_idx, unsigned int numa_node)
363 {
364 	struct nvme_dev *dev = set->driver_data;
365 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
366 	int queue_idx = (set == &dev->tagset) ? hctx_idx + 1 : 0;
367 	struct nvme_queue *nvmeq = dev->queues[queue_idx];
368 
369 	BUG_ON(!nvmeq);
370 	iod->nvmeq = nvmeq;
371 	return 0;
372 }
373 
374 static int nvme_pci_map_queues(struct blk_mq_tag_set *set)
375 {
376 	struct nvme_dev *dev = set->driver_data;
377 
378 	return blk_mq_pci_map_queues(set, to_pci_dev(dev->dev));
379 }
380 
381 /**
382  * __nvme_submit_cmd() - Copy a command into a queue and ring the doorbell
383  * @nvmeq: The queue to use
384  * @cmd: The command to send
385  *
386  * Safe to use from interrupt context
387  */
388 static void __nvme_submit_cmd(struct nvme_queue *nvmeq,
389 						struct nvme_command *cmd)
390 {
391 	u16 tail = nvmeq->sq_tail;
392 
393 	if (nvmeq->sq_cmds_io)
394 		memcpy_toio(&nvmeq->sq_cmds_io[tail], cmd, sizeof(*cmd));
395 	else
396 		memcpy(&nvmeq->sq_cmds[tail], cmd, sizeof(*cmd));
397 
398 	if (++tail == nvmeq->q_depth)
399 		tail = 0;
400 	if (nvme_dbbuf_update_and_check_event(tail, nvmeq->dbbuf_sq_db,
401 					      nvmeq->dbbuf_sq_ei))
402 		writel(tail, nvmeq->q_db);
403 	nvmeq->sq_tail = tail;
404 }
405 
406 static __le64 **iod_list(struct request *req)
407 {
408 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
409 	return (__le64 **)(iod->sg + blk_rq_nr_phys_segments(req));
410 }
411 
412 static blk_status_t nvme_init_iod(struct request *rq, struct nvme_dev *dev)
413 {
414 	struct nvme_iod *iod = blk_mq_rq_to_pdu(rq);
415 	int nseg = blk_rq_nr_phys_segments(rq);
416 	unsigned int size = blk_rq_payload_bytes(rq);
417 
418 	if (nseg > NVME_INT_PAGES || size > NVME_INT_BYTES(dev)) {
419 		iod->sg = kmalloc(nvme_iod_alloc_size(dev, size, nseg), GFP_ATOMIC);
420 		if (!iod->sg)
421 			return BLK_STS_RESOURCE;
422 	} else {
423 		iod->sg = iod->inline_sg;
424 	}
425 
426 	iod->aborted = 0;
427 	iod->npages = -1;
428 	iod->nents = 0;
429 	iod->length = size;
430 
431 	return BLK_STS_OK;
432 }
433 
434 static void nvme_free_iod(struct nvme_dev *dev, struct request *req)
435 {
436 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
437 	const int last_prp = dev->ctrl.page_size / 8 - 1;
438 	int i;
439 	__le64 **list = iod_list(req);
440 	dma_addr_t prp_dma = iod->first_dma;
441 
442 	if (iod->npages == 0)
443 		dma_pool_free(dev->prp_small_pool, list[0], prp_dma);
444 	for (i = 0; i < iod->npages; i++) {
445 		__le64 *prp_list = list[i];
446 		dma_addr_t next_prp_dma = le64_to_cpu(prp_list[last_prp]);
447 		dma_pool_free(dev->prp_page_pool, prp_list, prp_dma);
448 		prp_dma = next_prp_dma;
449 	}
450 
451 	if (iod->sg != iod->inline_sg)
452 		kfree(iod->sg);
453 }
454 
455 #ifdef CONFIG_BLK_DEV_INTEGRITY
456 static void nvme_dif_prep(u32 p, u32 v, struct t10_pi_tuple *pi)
457 {
458 	if (be32_to_cpu(pi->ref_tag) == v)
459 		pi->ref_tag = cpu_to_be32(p);
460 }
461 
462 static void nvme_dif_complete(u32 p, u32 v, struct t10_pi_tuple *pi)
463 {
464 	if (be32_to_cpu(pi->ref_tag) == p)
465 		pi->ref_tag = cpu_to_be32(v);
466 }
467 
468 /**
469  * nvme_dif_remap - remaps ref tags to bip seed and physical lba
470  *
471  * The virtual start sector is the one that was originally submitted by the
472  * block layer.	Due to partitioning, MD/DM cloning, etc. the actual physical
473  * start sector may be different. Remap protection information to match the
474  * physical LBA on writes, and back to the original seed on reads.
475  *
476  * Type 0 and 3 do not have a ref tag, so no remapping required.
477  */
478 static void nvme_dif_remap(struct request *req,
479 			void (*dif_swap)(u32 p, u32 v, struct t10_pi_tuple *pi))
480 {
481 	struct nvme_ns *ns = req->rq_disk->private_data;
482 	struct bio_integrity_payload *bip;
483 	struct t10_pi_tuple *pi;
484 	void *p, *pmap;
485 	u32 i, nlb, ts, phys, virt;
486 
487 	if (!ns->pi_type || ns->pi_type == NVME_NS_DPS_PI_TYPE3)
488 		return;
489 
490 	bip = bio_integrity(req->bio);
491 	if (!bip)
492 		return;
493 
494 	pmap = kmap_atomic(bip->bip_vec->bv_page) + bip->bip_vec->bv_offset;
495 
496 	p = pmap;
497 	virt = bip_get_seed(bip);
498 	phys = nvme_block_nr(ns, blk_rq_pos(req));
499 	nlb = (blk_rq_bytes(req) >> ns->lba_shift);
500 	ts = ns->disk->queue->integrity.tuple_size;
501 
502 	for (i = 0; i < nlb; i++, virt++, phys++) {
503 		pi = (struct t10_pi_tuple *)p;
504 		dif_swap(phys, virt, pi);
505 		p += ts;
506 	}
507 	kunmap_atomic(pmap);
508 }
509 #else /* CONFIG_BLK_DEV_INTEGRITY */
510 static void nvme_dif_remap(struct request *req,
511 			void (*dif_swap)(u32 p, u32 v, struct t10_pi_tuple *pi))
512 {
513 }
514 static void nvme_dif_prep(u32 p, u32 v, struct t10_pi_tuple *pi)
515 {
516 }
517 static void nvme_dif_complete(u32 p, u32 v, struct t10_pi_tuple *pi)
518 {
519 }
520 #endif
521 
522 static bool nvme_setup_prps(struct nvme_dev *dev, struct request *req)
523 {
524 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
525 	struct dma_pool *pool;
526 	int length = blk_rq_payload_bytes(req);
527 	struct scatterlist *sg = iod->sg;
528 	int dma_len = sg_dma_len(sg);
529 	u64 dma_addr = sg_dma_address(sg);
530 	u32 page_size = dev->ctrl.page_size;
531 	int offset = dma_addr & (page_size - 1);
532 	__le64 *prp_list;
533 	__le64 **list = iod_list(req);
534 	dma_addr_t prp_dma;
535 	int nprps, i;
536 
537 	length -= (page_size - offset);
538 	if (length <= 0)
539 		return true;
540 
541 	dma_len -= (page_size - offset);
542 	if (dma_len) {
543 		dma_addr += (page_size - offset);
544 	} else {
545 		sg = sg_next(sg);
546 		dma_addr = sg_dma_address(sg);
547 		dma_len = sg_dma_len(sg);
548 	}
549 
550 	if (length <= page_size) {
551 		iod->first_dma = dma_addr;
552 		return true;
553 	}
554 
555 	nprps = DIV_ROUND_UP(length, page_size);
556 	if (nprps <= (256 / 8)) {
557 		pool = dev->prp_small_pool;
558 		iod->npages = 0;
559 	} else {
560 		pool = dev->prp_page_pool;
561 		iod->npages = 1;
562 	}
563 
564 	prp_list = dma_pool_alloc(pool, GFP_ATOMIC, &prp_dma);
565 	if (!prp_list) {
566 		iod->first_dma = dma_addr;
567 		iod->npages = -1;
568 		return false;
569 	}
570 	list[0] = prp_list;
571 	iod->first_dma = prp_dma;
572 	i = 0;
573 	for (;;) {
574 		if (i == page_size >> 3) {
575 			__le64 *old_prp_list = prp_list;
576 			prp_list = dma_pool_alloc(pool, GFP_ATOMIC, &prp_dma);
577 			if (!prp_list)
578 				return false;
579 			list[iod->npages++] = prp_list;
580 			prp_list[0] = old_prp_list[i - 1];
581 			old_prp_list[i - 1] = cpu_to_le64(prp_dma);
582 			i = 1;
583 		}
584 		prp_list[i++] = cpu_to_le64(dma_addr);
585 		dma_len -= page_size;
586 		dma_addr += page_size;
587 		length -= page_size;
588 		if (length <= 0)
589 			break;
590 		if (dma_len > 0)
591 			continue;
592 		BUG_ON(dma_len < 0);
593 		sg = sg_next(sg);
594 		dma_addr = sg_dma_address(sg);
595 		dma_len = sg_dma_len(sg);
596 	}
597 
598 	return true;
599 }
600 
601 static blk_status_t nvme_map_data(struct nvme_dev *dev, struct request *req,
602 		struct nvme_command *cmnd)
603 {
604 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
605 	struct request_queue *q = req->q;
606 	enum dma_data_direction dma_dir = rq_data_dir(req) ?
607 			DMA_TO_DEVICE : DMA_FROM_DEVICE;
608 	blk_status_t ret = BLK_STS_IOERR;
609 
610 	sg_init_table(iod->sg, blk_rq_nr_phys_segments(req));
611 	iod->nents = blk_rq_map_sg(q, req, iod->sg);
612 	if (!iod->nents)
613 		goto out;
614 
615 	ret = BLK_STS_RESOURCE;
616 	if (!dma_map_sg_attrs(dev->dev, iod->sg, iod->nents, dma_dir,
617 				DMA_ATTR_NO_WARN))
618 		goto out;
619 
620 	if (!nvme_setup_prps(dev, req))
621 		goto out_unmap;
622 
623 	ret = BLK_STS_IOERR;
624 	if (blk_integrity_rq(req)) {
625 		if (blk_rq_count_integrity_sg(q, req->bio) != 1)
626 			goto out_unmap;
627 
628 		sg_init_table(&iod->meta_sg, 1);
629 		if (blk_rq_map_integrity_sg(q, req->bio, &iod->meta_sg) != 1)
630 			goto out_unmap;
631 
632 		if (rq_data_dir(req))
633 			nvme_dif_remap(req, nvme_dif_prep);
634 
635 		if (!dma_map_sg(dev->dev, &iod->meta_sg, 1, dma_dir))
636 			goto out_unmap;
637 	}
638 
639 	cmnd->rw.dptr.prp1 = cpu_to_le64(sg_dma_address(iod->sg));
640 	cmnd->rw.dptr.prp2 = cpu_to_le64(iod->first_dma);
641 	if (blk_integrity_rq(req))
642 		cmnd->rw.metadata = cpu_to_le64(sg_dma_address(&iod->meta_sg));
643 	return BLK_STS_OK;
644 
645 out_unmap:
646 	dma_unmap_sg(dev->dev, iod->sg, iod->nents, dma_dir);
647 out:
648 	return ret;
649 }
650 
651 static void nvme_unmap_data(struct nvme_dev *dev, struct request *req)
652 {
653 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
654 	enum dma_data_direction dma_dir = rq_data_dir(req) ?
655 			DMA_TO_DEVICE : DMA_FROM_DEVICE;
656 
657 	if (iod->nents) {
658 		dma_unmap_sg(dev->dev, iod->sg, iod->nents, dma_dir);
659 		if (blk_integrity_rq(req)) {
660 			if (!rq_data_dir(req))
661 				nvme_dif_remap(req, nvme_dif_complete);
662 			dma_unmap_sg(dev->dev, &iod->meta_sg, 1, dma_dir);
663 		}
664 	}
665 
666 	nvme_cleanup_cmd(req);
667 	nvme_free_iod(dev, req);
668 }
669 
670 /*
671  * NOTE: ns is NULL when called on the admin queue.
672  */
673 static blk_status_t nvme_queue_rq(struct blk_mq_hw_ctx *hctx,
674 			 const struct blk_mq_queue_data *bd)
675 {
676 	struct nvme_ns *ns = hctx->queue->queuedata;
677 	struct nvme_queue *nvmeq = hctx->driver_data;
678 	struct nvme_dev *dev = nvmeq->dev;
679 	struct request *req = bd->rq;
680 	struct nvme_command cmnd;
681 	blk_status_t ret;
682 
683 	ret = nvme_setup_cmd(ns, req, &cmnd);
684 	if (ret)
685 		return ret;
686 
687 	ret = nvme_init_iod(req, dev);
688 	if (ret)
689 		goto out_free_cmd;
690 
691 	if (blk_rq_nr_phys_segments(req)) {
692 		ret = nvme_map_data(dev, req, &cmnd);
693 		if (ret)
694 			goto out_cleanup_iod;
695 	}
696 
697 	blk_mq_start_request(req);
698 
699 	spin_lock_irq(&nvmeq->q_lock);
700 	if (unlikely(nvmeq->cq_vector < 0)) {
701 		ret = BLK_STS_IOERR;
702 		spin_unlock_irq(&nvmeq->q_lock);
703 		goto out_cleanup_iod;
704 	}
705 	__nvme_submit_cmd(nvmeq, &cmnd);
706 	nvme_process_cq(nvmeq);
707 	spin_unlock_irq(&nvmeq->q_lock);
708 	return BLK_STS_OK;
709 out_cleanup_iod:
710 	nvme_free_iod(dev, req);
711 out_free_cmd:
712 	nvme_cleanup_cmd(req);
713 	return ret;
714 }
715 
716 static void nvme_pci_complete_rq(struct request *req)
717 {
718 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
719 
720 	nvme_unmap_data(iod->nvmeq->dev, req);
721 	nvme_complete_rq(req);
722 }
723 
724 /* We read the CQE phase first to check if the rest of the entry is valid */
725 static inline bool nvme_cqe_valid(struct nvme_queue *nvmeq, u16 head,
726 		u16 phase)
727 {
728 	return (le16_to_cpu(nvmeq->cqes[head].status) & 1) == phase;
729 }
730 
731 static inline void nvme_ring_cq_doorbell(struct nvme_queue *nvmeq)
732 {
733 	u16 head = nvmeq->cq_head;
734 
735 	if (likely(nvmeq->cq_vector >= 0)) {
736 		if (nvme_dbbuf_update_and_check_event(head, nvmeq->dbbuf_cq_db,
737 						      nvmeq->dbbuf_cq_ei))
738 			writel(head, nvmeq->q_db + nvmeq->dev->db_stride);
739 	}
740 }
741 
742 static inline void nvme_handle_cqe(struct nvme_queue *nvmeq,
743 		struct nvme_completion *cqe)
744 {
745 	struct request *req;
746 
747 	if (unlikely(cqe->command_id >= nvmeq->q_depth)) {
748 		dev_warn(nvmeq->dev->ctrl.device,
749 			"invalid id %d completed on queue %d\n",
750 			cqe->command_id, le16_to_cpu(cqe->sq_id));
751 		return;
752 	}
753 
754 	/*
755 	 * AEN requests are special as they don't time out and can
756 	 * survive any kind of queue freeze and often don't respond to
757 	 * aborts.  We don't even bother to allocate a struct request
758 	 * for them but rather special case them here.
759 	 */
760 	if (unlikely(nvmeq->qid == 0 &&
761 			cqe->command_id >= NVME_AQ_BLKMQ_DEPTH)) {
762 		nvme_complete_async_event(&nvmeq->dev->ctrl,
763 				cqe->status, &cqe->result);
764 		return;
765 	}
766 
767 	req = blk_mq_tag_to_rq(*nvmeq->tags, cqe->command_id);
768 	nvme_end_request(req, cqe->status, cqe->result);
769 }
770 
771 static inline bool nvme_read_cqe(struct nvme_queue *nvmeq,
772 		struct nvme_completion *cqe)
773 {
774 	if (nvme_cqe_valid(nvmeq, nvmeq->cq_head, nvmeq->cq_phase)) {
775 		*cqe = nvmeq->cqes[nvmeq->cq_head];
776 
777 		if (++nvmeq->cq_head == nvmeq->q_depth) {
778 			nvmeq->cq_head = 0;
779 			nvmeq->cq_phase = !nvmeq->cq_phase;
780 		}
781 		return true;
782 	}
783 	return false;
784 }
785 
786 static void nvme_process_cq(struct nvme_queue *nvmeq)
787 {
788 	struct nvme_completion cqe;
789 	int consumed = 0;
790 
791 	while (nvme_read_cqe(nvmeq, &cqe)) {
792 		nvme_handle_cqe(nvmeq, &cqe);
793 		consumed++;
794 	}
795 
796 	if (consumed) {
797 		nvme_ring_cq_doorbell(nvmeq);
798 		nvmeq->cqe_seen = 1;
799 	}
800 }
801 
802 static irqreturn_t nvme_irq(int irq, void *data)
803 {
804 	irqreturn_t result;
805 	struct nvme_queue *nvmeq = data;
806 	spin_lock(&nvmeq->q_lock);
807 	nvme_process_cq(nvmeq);
808 	result = nvmeq->cqe_seen ? IRQ_HANDLED : IRQ_NONE;
809 	nvmeq->cqe_seen = 0;
810 	spin_unlock(&nvmeq->q_lock);
811 	return result;
812 }
813 
814 static irqreturn_t nvme_irq_check(int irq, void *data)
815 {
816 	struct nvme_queue *nvmeq = data;
817 	if (nvme_cqe_valid(nvmeq, nvmeq->cq_head, nvmeq->cq_phase))
818 		return IRQ_WAKE_THREAD;
819 	return IRQ_NONE;
820 }
821 
822 static int __nvme_poll(struct nvme_queue *nvmeq, unsigned int tag)
823 {
824 	struct nvme_completion cqe;
825 	int found = 0, consumed = 0;
826 
827 	if (!nvme_cqe_valid(nvmeq, nvmeq->cq_head, nvmeq->cq_phase))
828 		return 0;
829 
830 	spin_lock_irq(&nvmeq->q_lock);
831 	while (nvme_read_cqe(nvmeq, &cqe)) {
832 		nvme_handle_cqe(nvmeq, &cqe);
833 		consumed++;
834 
835 		if (tag == cqe.command_id) {
836 			found = 1;
837 			break;
838 		}
839        }
840 
841 	if (consumed)
842 		nvme_ring_cq_doorbell(nvmeq);
843 	spin_unlock_irq(&nvmeq->q_lock);
844 
845 	return found;
846 }
847 
848 static int nvme_poll(struct blk_mq_hw_ctx *hctx, unsigned int tag)
849 {
850 	struct nvme_queue *nvmeq = hctx->driver_data;
851 
852 	return __nvme_poll(nvmeq, tag);
853 }
854 
855 static void nvme_pci_submit_async_event(struct nvme_ctrl *ctrl, int aer_idx)
856 {
857 	struct nvme_dev *dev = to_nvme_dev(ctrl);
858 	struct nvme_queue *nvmeq = dev->queues[0];
859 	struct nvme_command c;
860 
861 	memset(&c, 0, sizeof(c));
862 	c.common.opcode = nvme_admin_async_event;
863 	c.common.command_id = NVME_AQ_BLKMQ_DEPTH + aer_idx;
864 
865 	spin_lock_irq(&nvmeq->q_lock);
866 	__nvme_submit_cmd(nvmeq, &c);
867 	spin_unlock_irq(&nvmeq->q_lock);
868 }
869 
870 static int adapter_delete_queue(struct nvme_dev *dev, u8 opcode, u16 id)
871 {
872 	struct nvme_command c;
873 
874 	memset(&c, 0, sizeof(c));
875 	c.delete_queue.opcode = opcode;
876 	c.delete_queue.qid = cpu_to_le16(id);
877 
878 	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
879 }
880 
881 static int adapter_alloc_cq(struct nvme_dev *dev, u16 qid,
882 						struct nvme_queue *nvmeq)
883 {
884 	struct nvme_command c;
885 	int flags = NVME_QUEUE_PHYS_CONTIG | NVME_CQ_IRQ_ENABLED;
886 
887 	/*
888 	 * Note: we (ab)use the fact the the prp fields survive if no data
889 	 * is attached to the request.
890 	 */
891 	memset(&c, 0, sizeof(c));
892 	c.create_cq.opcode = nvme_admin_create_cq;
893 	c.create_cq.prp1 = cpu_to_le64(nvmeq->cq_dma_addr);
894 	c.create_cq.cqid = cpu_to_le16(qid);
895 	c.create_cq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
896 	c.create_cq.cq_flags = cpu_to_le16(flags);
897 	c.create_cq.irq_vector = cpu_to_le16(nvmeq->cq_vector);
898 
899 	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
900 }
901 
902 static int adapter_alloc_sq(struct nvme_dev *dev, u16 qid,
903 						struct nvme_queue *nvmeq)
904 {
905 	struct nvme_command c;
906 	int flags = NVME_QUEUE_PHYS_CONTIG;
907 
908 	/*
909 	 * Note: we (ab)use the fact the the prp fields survive if no data
910 	 * is attached to the request.
911 	 */
912 	memset(&c, 0, sizeof(c));
913 	c.create_sq.opcode = nvme_admin_create_sq;
914 	c.create_sq.prp1 = cpu_to_le64(nvmeq->sq_dma_addr);
915 	c.create_sq.sqid = cpu_to_le16(qid);
916 	c.create_sq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
917 	c.create_sq.sq_flags = cpu_to_le16(flags);
918 	c.create_sq.cqid = cpu_to_le16(qid);
919 
920 	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
921 }
922 
923 static int adapter_delete_cq(struct nvme_dev *dev, u16 cqid)
924 {
925 	return adapter_delete_queue(dev, nvme_admin_delete_cq, cqid);
926 }
927 
928 static int adapter_delete_sq(struct nvme_dev *dev, u16 sqid)
929 {
930 	return adapter_delete_queue(dev, nvme_admin_delete_sq, sqid);
931 }
932 
933 static void abort_endio(struct request *req, blk_status_t error)
934 {
935 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
936 	struct nvme_queue *nvmeq = iod->nvmeq;
937 
938 	dev_warn(nvmeq->dev->ctrl.device,
939 		 "Abort status: 0x%x", nvme_req(req)->status);
940 	atomic_inc(&nvmeq->dev->ctrl.abort_limit);
941 	blk_mq_free_request(req);
942 }
943 
944 static bool nvme_should_reset(struct nvme_dev *dev, u32 csts)
945 {
946 
947 	/* If true, indicates loss of adapter communication, possibly by a
948 	 * NVMe Subsystem reset.
949 	 */
950 	bool nssro = dev->subsystem && (csts & NVME_CSTS_NSSRO);
951 
952 	/* If there is a reset ongoing, we shouldn't reset again. */
953 	if (dev->ctrl.state == NVME_CTRL_RESETTING)
954 		return false;
955 
956 	/* We shouldn't reset unless the controller is on fatal error state
957 	 * _or_ if we lost the communication with it.
958 	 */
959 	if (!(csts & NVME_CSTS_CFS) && !nssro)
960 		return false;
961 
962 	/* If PCI error recovery process is happening, we cannot reset or
963 	 * the recovery mechanism will surely fail.
964 	 */
965 	if (pci_channel_offline(to_pci_dev(dev->dev)))
966 		return false;
967 
968 	return true;
969 }
970 
971 static void nvme_warn_reset(struct nvme_dev *dev, u32 csts)
972 {
973 	/* Read a config register to help see what died. */
974 	u16 pci_status;
975 	int result;
976 
977 	result = pci_read_config_word(to_pci_dev(dev->dev), PCI_STATUS,
978 				      &pci_status);
979 	if (result == PCIBIOS_SUCCESSFUL)
980 		dev_warn(dev->ctrl.device,
981 			 "controller is down; will reset: CSTS=0x%x, PCI_STATUS=0x%hx\n",
982 			 csts, pci_status);
983 	else
984 		dev_warn(dev->ctrl.device,
985 			 "controller is down; will reset: CSTS=0x%x, PCI_STATUS read failed (%d)\n",
986 			 csts, result);
987 }
988 
989 static enum blk_eh_timer_return nvme_timeout(struct request *req, bool reserved)
990 {
991 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
992 	struct nvme_queue *nvmeq = iod->nvmeq;
993 	struct nvme_dev *dev = nvmeq->dev;
994 	struct request *abort_req;
995 	struct nvme_command cmd;
996 	u32 csts = readl(dev->bar + NVME_REG_CSTS);
997 
998 	/*
999 	 * Reset immediately if the controller is failed
1000 	 */
1001 	if (nvme_should_reset(dev, csts)) {
1002 		nvme_warn_reset(dev, csts);
1003 		nvme_dev_disable(dev, false);
1004 		nvme_reset_ctrl(&dev->ctrl);
1005 		return BLK_EH_HANDLED;
1006 	}
1007 
1008 	/*
1009 	 * Did we miss an interrupt?
1010 	 */
1011 	if (__nvme_poll(nvmeq, req->tag)) {
1012 		dev_warn(dev->ctrl.device,
1013 			 "I/O %d QID %d timeout, completion polled\n",
1014 			 req->tag, nvmeq->qid);
1015 		return BLK_EH_HANDLED;
1016 	}
1017 
1018 	/*
1019 	 * Shutdown immediately if controller times out while starting. The
1020 	 * reset work will see the pci device disabled when it gets the forced
1021 	 * cancellation error. All outstanding requests are completed on
1022 	 * shutdown, so we return BLK_EH_HANDLED.
1023 	 */
1024 	if (dev->ctrl.state == NVME_CTRL_RESETTING) {
1025 		dev_warn(dev->ctrl.device,
1026 			 "I/O %d QID %d timeout, disable controller\n",
1027 			 req->tag, nvmeq->qid);
1028 		nvme_dev_disable(dev, false);
1029 		nvme_req(req)->flags |= NVME_REQ_CANCELLED;
1030 		return BLK_EH_HANDLED;
1031 	}
1032 
1033 	/*
1034  	 * Shutdown the controller immediately and schedule a reset if the
1035  	 * command was already aborted once before and still hasn't been
1036  	 * returned to the driver, or if this is the admin queue.
1037 	 */
1038 	if (!nvmeq->qid || iod->aborted) {
1039 		dev_warn(dev->ctrl.device,
1040 			 "I/O %d QID %d timeout, reset controller\n",
1041 			 req->tag, nvmeq->qid);
1042 		nvme_dev_disable(dev, false);
1043 		nvme_reset_ctrl(&dev->ctrl);
1044 
1045 		/*
1046 		 * Mark the request as handled, since the inline shutdown
1047 		 * forces all outstanding requests to complete.
1048 		 */
1049 		nvme_req(req)->flags |= NVME_REQ_CANCELLED;
1050 		return BLK_EH_HANDLED;
1051 	}
1052 
1053 	if (atomic_dec_return(&dev->ctrl.abort_limit) < 0) {
1054 		atomic_inc(&dev->ctrl.abort_limit);
1055 		return BLK_EH_RESET_TIMER;
1056 	}
1057 	iod->aborted = 1;
1058 
1059 	memset(&cmd, 0, sizeof(cmd));
1060 	cmd.abort.opcode = nvme_admin_abort_cmd;
1061 	cmd.abort.cid = req->tag;
1062 	cmd.abort.sqid = cpu_to_le16(nvmeq->qid);
1063 
1064 	dev_warn(nvmeq->dev->ctrl.device,
1065 		"I/O %d QID %d timeout, aborting\n",
1066 		 req->tag, nvmeq->qid);
1067 
1068 	abort_req = nvme_alloc_request(dev->ctrl.admin_q, &cmd,
1069 			BLK_MQ_REQ_NOWAIT, NVME_QID_ANY);
1070 	if (IS_ERR(abort_req)) {
1071 		atomic_inc(&dev->ctrl.abort_limit);
1072 		return BLK_EH_RESET_TIMER;
1073 	}
1074 
1075 	abort_req->timeout = ADMIN_TIMEOUT;
1076 	abort_req->end_io_data = NULL;
1077 	blk_execute_rq_nowait(abort_req->q, NULL, abort_req, 0, abort_endio);
1078 
1079 	/*
1080 	 * The aborted req will be completed on receiving the abort req.
1081 	 * We enable the timer again. If hit twice, it'll cause a device reset,
1082 	 * as the device then is in a faulty state.
1083 	 */
1084 	return BLK_EH_RESET_TIMER;
1085 }
1086 
1087 static void nvme_free_queue(struct nvme_queue *nvmeq)
1088 {
1089 	dma_free_coherent(nvmeq->q_dmadev, CQ_SIZE(nvmeq->q_depth),
1090 				(void *)nvmeq->cqes, nvmeq->cq_dma_addr);
1091 	if (nvmeq->sq_cmds)
1092 		dma_free_coherent(nvmeq->q_dmadev, SQ_SIZE(nvmeq->q_depth),
1093 					nvmeq->sq_cmds, nvmeq->sq_dma_addr);
1094 	kfree(nvmeq);
1095 }
1096 
1097 static void nvme_free_queues(struct nvme_dev *dev, int lowest)
1098 {
1099 	int i;
1100 
1101 	for (i = dev->ctrl.queue_count - 1; i >= lowest; i--) {
1102 		struct nvme_queue *nvmeq = dev->queues[i];
1103 		dev->ctrl.queue_count--;
1104 		dev->queues[i] = NULL;
1105 		nvme_free_queue(nvmeq);
1106 	}
1107 }
1108 
1109 /**
1110  * nvme_suspend_queue - put queue into suspended state
1111  * @nvmeq - queue to suspend
1112  */
1113 static int nvme_suspend_queue(struct nvme_queue *nvmeq)
1114 {
1115 	int vector;
1116 
1117 	spin_lock_irq(&nvmeq->q_lock);
1118 	if (nvmeq->cq_vector == -1) {
1119 		spin_unlock_irq(&nvmeq->q_lock);
1120 		return 1;
1121 	}
1122 	vector = nvmeq->cq_vector;
1123 	nvmeq->dev->online_queues--;
1124 	nvmeq->cq_vector = -1;
1125 	spin_unlock_irq(&nvmeq->q_lock);
1126 
1127 	if (!nvmeq->qid && nvmeq->dev->ctrl.admin_q)
1128 		blk_mq_quiesce_queue(nvmeq->dev->ctrl.admin_q);
1129 
1130 	pci_free_irq(to_pci_dev(nvmeq->dev->dev), vector, nvmeq);
1131 
1132 	return 0;
1133 }
1134 
1135 static void nvme_disable_admin_queue(struct nvme_dev *dev, bool shutdown)
1136 {
1137 	struct nvme_queue *nvmeq = dev->queues[0];
1138 
1139 	if (!nvmeq)
1140 		return;
1141 	if (nvme_suspend_queue(nvmeq))
1142 		return;
1143 
1144 	if (shutdown)
1145 		nvme_shutdown_ctrl(&dev->ctrl);
1146 	else
1147 		nvme_disable_ctrl(&dev->ctrl, dev->ctrl.cap);
1148 
1149 	spin_lock_irq(&nvmeq->q_lock);
1150 	nvme_process_cq(nvmeq);
1151 	spin_unlock_irq(&nvmeq->q_lock);
1152 }
1153 
1154 static int nvme_cmb_qdepth(struct nvme_dev *dev, int nr_io_queues,
1155 				int entry_size)
1156 {
1157 	int q_depth = dev->q_depth;
1158 	unsigned q_size_aligned = roundup(q_depth * entry_size,
1159 					  dev->ctrl.page_size);
1160 
1161 	if (q_size_aligned * nr_io_queues > dev->cmb_size) {
1162 		u64 mem_per_q = div_u64(dev->cmb_size, nr_io_queues);
1163 		mem_per_q = round_down(mem_per_q, dev->ctrl.page_size);
1164 		q_depth = div_u64(mem_per_q, entry_size);
1165 
1166 		/*
1167 		 * Ensure the reduced q_depth is above some threshold where it
1168 		 * would be better to map queues in system memory with the
1169 		 * original depth
1170 		 */
1171 		if (q_depth < 64)
1172 			return -ENOMEM;
1173 	}
1174 
1175 	return q_depth;
1176 }
1177 
1178 static int nvme_alloc_sq_cmds(struct nvme_dev *dev, struct nvme_queue *nvmeq,
1179 				int qid, int depth)
1180 {
1181 	if (qid && dev->cmb && use_cmb_sqes && NVME_CMB_SQS(dev->cmbsz)) {
1182 		unsigned offset = (qid - 1) * roundup(SQ_SIZE(depth),
1183 						      dev->ctrl.page_size);
1184 		nvmeq->sq_dma_addr = dev->cmb_dma_addr + offset;
1185 		nvmeq->sq_cmds_io = dev->cmb + offset;
1186 	} else {
1187 		nvmeq->sq_cmds = dma_alloc_coherent(dev->dev, SQ_SIZE(depth),
1188 					&nvmeq->sq_dma_addr, GFP_KERNEL);
1189 		if (!nvmeq->sq_cmds)
1190 			return -ENOMEM;
1191 	}
1192 
1193 	return 0;
1194 }
1195 
1196 static struct nvme_queue *nvme_alloc_queue(struct nvme_dev *dev, int qid,
1197 							int depth, int node)
1198 {
1199 	struct nvme_queue *nvmeq = kzalloc_node(sizeof(*nvmeq), GFP_KERNEL,
1200 							node);
1201 	if (!nvmeq)
1202 		return NULL;
1203 
1204 	nvmeq->cqes = dma_zalloc_coherent(dev->dev, CQ_SIZE(depth),
1205 					  &nvmeq->cq_dma_addr, GFP_KERNEL);
1206 	if (!nvmeq->cqes)
1207 		goto free_nvmeq;
1208 
1209 	if (nvme_alloc_sq_cmds(dev, nvmeq, qid, depth))
1210 		goto free_cqdma;
1211 
1212 	nvmeq->q_dmadev = dev->dev;
1213 	nvmeq->dev = dev;
1214 	spin_lock_init(&nvmeq->q_lock);
1215 	nvmeq->cq_head = 0;
1216 	nvmeq->cq_phase = 1;
1217 	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
1218 	nvmeq->q_depth = depth;
1219 	nvmeq->qid = qid;
1220 	nvmeq->cq_vector = -1;
1221 	dev->queues[qid] = nvmeq;
1222 	dev->ctrl.queue_count++;
1223 
1224 	return nvmeq;
1225 
1226  free_cqdma:
1227 	dma_free_coherent(dev->dev, CQ_SIZE(depth), (void *)nvmeq->cqes,
1228 							nvmeq->cq_dma_addr);
1229  free_nvmeq:
1230 	kfree(nvmeq);
1231 	return NULL;
1232 }
1233 
1234 static int queue_request_irq(struct nvme_queue *nvmeq)
1235 {
1236 	struct pci_dev *pdev = to_pci_dev(nvmeq->dev->dev);
1237 	int nr = nvmeq->dev->ctrl.instance;
1238 
1239 	if (use_threaded_interrupts) {
1240 		return pci_request_irq(pdev, nvmeq->cq_vector, nvme_irq_check,
1241 				nvme_irq, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
1242 	} else {
1243 		return pci_request_irq(pdev, nvmeq->cq_vector, nvme_irq,
1244 				NULL, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
1245 	}
1246 }
1247 
1248 static void nvme_init_queue(struct nvme_queue *nvmeq, u16 qid)
1249 {
1250 	struct nvme_dev *dev = nvmeq->dev;
1251 
1252 	spin_lock_irq(&nvmeq->q_lock);
1253 	nvmeq->sq_tail = 0;
1254 	nvmeq->cq_head = 0;
1255 	nvmeq->cq_phase = 1;
1256 	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
1257 	memset((void *)nvmeq->cqes, 0, CQ_SIZE(nvmeq->q_depth));
1258 	nvme_dbbuf_init(dev, nvmeq, qid);
1259 	dev->online_queues++;
1260 	spin_unlock_irq(&nvmeq->q_lock);
1261 }
1262 
1263 static int nvme_create_queue(struct nvme_queue *nvmeq, int qid)
1264 {
1265 	struct nvme_dev *dev = nvmeq->dev;
1266 	int result;
1267 
1268 	nvmeq->cq_vector = qid - 1;
1269 	result = adapter_alloc_cq(dev, qid, nvmeq);
1270 	if (result < 0)
1271 		return result;
1272 
1273 	result = adapter_alloc_sq(dev, qid, nvmeq);
1274 	if (result < 0)
1275 		goto release_cq;
1276 
1277 	result = queue_request_irq(nvmeq);
1278 	if (result < 0)
1279 		goto release_sq;
1280 
1281 	nvme_init_queue(nvmeq, qid);
1282 	return result;
1283 
1284  release_sq:
1285 	adapter_delete_sq(dev, qid);
1286  release_cq:
1287 	adapter_delete_cq(dev, qid);
1288 	return result;
1289 }
1290 
1291 static const struct blk_mq_ops nvme_mq_admin_ops = {
1292 	.queue_rq	= nvme_queue_rq,
1293 	.complete	= nvme_pci_complete_rq,
1294 	.init_hctx	= nvme_admin_init_hctx,
1295 	.exit_hctx      = nvme_admin_exit_hctx,
1296 	.init_request	= nvme_init_request,
1297 	.timeout	= nvme_timeout,
1298 };
1299 
1300 static const struct blk_mq_ops nvme_mq_ops = {
1301 	.queue_rq	= nvme_queue_rq,
1302 	.complete	= nvme_pci_complete_rq,
1303 	.init_hctx	= nvme_init_hctx,
1304 	.init_request	= nvme_init_request,
1305 	.map_queues	= nvme_pci_map_queues,
1306 	.timeout	= nvme_timeout,
1307 	.poll		= nvme_poll,
1308 };
1309 
1310 static void nvme_dev_remove_admin(struct nvme_dev *dev)
1311 {
1312 	if (dev->ctrl.admin_q && !blk_queue_dying(dev->ctrl.admin_q)) {
1313 		/*
1314 		 * If the controller was reset during removal, it's possible
1315 		 * user requests may be waiting on a stopped queue. Start the
1316 		 * queue to flush these to completion.
1317 		 */
1318 		blk_mq_unquiesce_queue(dev->ctrl.admin_q);
1319 		blk_cleanup_queue(dev->ctrl.admin_q);
1320 		blk_mq_free_tag_set(&dev->admin_tagset);
1321 	}
1322 }
1323 
1324 static int nvme_alloc_admin_tags(struct nvme_dev *dev)
1325 {
1326 	if (!dev->ctrl.admin_q) {
1327 		dev->admin_tagset.ops = &nvme_mq_admin_ops;
1328 		dev->admin_tagset.nr_hw_queues = 1;
1329 
1330 		/*
1331 		 * Subtract one to leave an empty queue entry for 'Full Queue'
1332 		 * condition. See NVM-Express 1.2 specification, section 4.1.2.
1333 		 */
1334 		dev->admin_tagset.queue_depth = NVME_AQ_BLKMQ_DEPTH - 1;
1335 		dev->admin_tagset.timeout = ADMIN_TIMEOUT;
1336 		dev->admin_tagset.numa_node = dev_to_node(dev->dev);
1337 		dev->admin_tagset.cmd_size = nvme_cmd_size(dev);
1338 		dev->admin_tagset.flags = BLK_MQ_F_NO_SCHED;
1339 		dev->admin_tagset.driver_data = dev;
1340 
1341 		if (blk_mq_alloc_tag_set(&dev->admin_tagset))
1342 			return -ENOMEM;
1343 
1344 		dev->ctrl.admin_q = blk_mq_init_queue(&dev->admin_tagset);
1345 		if (IS_ERR(dev->ctrl.admin_q)) {
1346 			blk_mq_free_tag_set(&dev->admin_tagset);
1347 			return -ENOMEM;
1348 		}
1349 		if (!blk_get_queue(dev->ctrl.admin_q)) {
1350 			nvme_dev_remove_admin(dev);
1351 			dev->ctrl.admin_q = NULL;
1352 			return -ENODEV;
1353 		}
1354 	} else
1355 		blk_mq_unquiesce_queue(dev->ctrl.admin_q);
1356 
1357 	return 0;
1358 }
1359 
1360 static unsigned long db_bar_size(struct nvme_dev *dev, unsigned nr_io_queues)
1361 {
1362 	return NVME_REG_DBS + ((nr_io_queues + 1) * 8 * dev->db_stride);
1363 }
1364 
1365 static int nvme_remap_bar(struct nvme_dev *dev, unsigned long size)
1366 {
1367 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1368 
1369 	if (size <= dev->bar_mapped_size)
1370 		return 0;
1371 	if (size > pci_resource_len(pdev, 0))
1372 		return -ENOMEM;
1373 	if (dev->bar)
1374 		iounmap(dev->bar);
1375 	dev->bar = ioremap(pci_resource_start(pdev, 0), size);
1376 	if (!dev->bar) {
1377 		dev->bar_mapped_size = 0;
1378 		return -ENOMEM;
1379 	}
1380 	dev->bar_mapped_size = size;
1381 	dev->dbs = dev->bar + NVME_REG_DBS;
1382 
1383 	return 0;
1384 }
1385 
1386 static int nvme_pci_configure_admin_queue(struct nvme_dev *dev)
1387 {
1388 	int result;
1389 	u32 aqa;
1390 	struct nvme_queue *nvmeq;
1391 
1392 	result = nvme_remap_bar(dev, db_bar_size(dev, 0));
1393 	if (result < 0)
1394 		return result;
1395 
1396 	dev->subsystem = readl(dev->bar + NVME_REG_VS) >= NVME_VS(1, 1, 0) ?
1397 				NVME_CAP_NSSRC(dev->ctrl.cap) : 0;
1398 
1399 	if (dev->subsystem &&
1400 	    (readl(dev->bar + NVME_REG_CSTS) & NVME_CSTS_NSSRO))
1401 		writel(NVME_CSTS_NSSRO, dev->bar + NVME_REG_CSTS);
1402 
1403 	result = nvme_disable_ctrl(&dev->ctrl, dev->ctrl.cap);
1404 	if (result < 0)
1405 		return result;
1406 
1407 	nvmeq = dev->queues[0];
1408 	if (!nvmeq) {
1409 		nvmeq = nvme_alloc_queue(dev, 0, NVME_AQ_DEPTH,
1410 					dev_to_node(dev->dev));
1411 		if (!nvmeq)
1412 			return -ENOMEM;
1413 	}
1414 
1415 	aqa = nvmeq->q_depth - 1;
1416 	aqa |= aqa << 16;
1417 
1418 	writel(aqa, dev->bar + NVME_REG_AQA);
1419 	lo_hi_writeq(nvmeq->sq_dma_addr, dev->bar + NVME_REG_ASQ);
1420 	lo_hi_writeq(nvmeq->cq_dma_addr, dev->bar + NVME_REG_ACQ);
1421 
1422 	result = nvme_enable_ctrl(&dev->ctrl, dev->ctrl.cap);
1423 	if (result)
1424 		return result;
1425 
1426 	nvmeq->cq_vector = 0;
1427 	result = queue_request_irq(nvmeq);
1428 	if (result) {
1429 		nvmeq->cq_vector = -1;
1430 		return result;
1431 	}
1432 
1433 	return result;
1434 }
1435 
1436 static int nvme_create_io_queues(struct nvme_dev *dev)
1437 {
1438 	unsigned i, max;
1439 	int ret = 0;
1440 
1441 	for (i = dev->ctrl.queue_count; i <= dev->max_qid; i++) {
1442 		/* vector == qid - 1, match nvme_create_queue */
1443 		if (!nvme_alloc_queue(dev, i, dev->q_depth,
1444 		     pci_irq_get_node(to_pci_dev(dev->dev), i - 1))) {
1445 			ret = -ENOMEM;
1446 			break;
1447 		}
1448 	}
1449 
1450 	max = min(dev->max_qid, dev->ctrl.queue_count - 1);
1451 	for (i = dev->online_queues; i <= max; i++) {
1452 		ret = nvme_create_queue(dev->queues[i], i);
1453 		if (ret)
1454 			break;
1455 	}
1456 
1457 	/*
1458 	 * Ignore failing Create SQ/CQ commands, we can continue with less
1459 	 * than the desired aount of queues, and even a controller without
1460 	 * I/O queues an still be used to issue admin commands.  This might
1461 	 * be useful to upgrade a buggy firmware for example.
1462 	 */
1463 	return ret >= 0 ? 0 : ret;
1464 }
1465 
1466 static ssize_t nvme_cmb_show(struct device *dev,
1467 			     struct device_attribute *attr,
1468 			     char *buf)
1469 {
1470 	struct nvme_dev *ndev = to_nvme_dev(dev_get_drvdata(dev));
1471 
1472 	return scnprintf(buf, PAGE_SIZE, "cmbloc : x%08x\ncmbsz  : x%08x\n",
1473 		       ndev->cmbloc, ndev->cmbsz);
1474 }
1475 static DEVICE_ATTR(cmb, S_IRUGO, nvme_cmb_show, NULL);
1476 
1477 static void __iomem *nvme_map_cmb(struct nvme_dev *dev)
1478 {
1479 	u64 szu, size, offset;
1480 	resource_size_t bar_size;
1481 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1482 	void __iomem *cmb;
1483 	dma_addr_t dma_addr;
1484 
1485 	dev->cmbsz = readl(dev->bar + NVME_REG_CMBSZ);
1486 	if (!(NVME_CMB_SZ(dev->cmbsz)))
1487 		return NULL;
1488 	dev->cmbloc = readl(dev->bar + NVME_REG_CMBLOC);
1489 
1490 	if (!use_cmb_sqes)
1491 		return NULL;
1492 
1493 	szu = (u64)1 << (12 + 4 * NVME_CMB_SZU(dev->cmbsz));
1494 	size = szu * NVME_CMB_SZ(dev->cmbsz);
1495 	offset = szu * NVME_CMB_OFST(dev->cmbloc);
1496 	bar_size = pci_resource_len(pdev, NVME_CMB_BIR(dev->cmbloc));
1497 
1498 	if (offset > bar_size)
1499 		return NULL;
1500 
1501 	/*
1502 	 * Controllers may support a CMB size larger than their BAR,
1503 	 * for example, due to being behind a bridge. Reduce the CMB to
1504 	 * the reported size of the BAR
1505 	 */
1506 	if (size > bar_size - offset)
1507 		size = bar_size - offset;
1508 
1509 	dma_addr = pci_resource_start(pdev, NVME_CMB_BIR(dev->cmbloc)) + offset;
1510 	cmb = ioremap_wc(dma_addr, size);
1511 	if (!cmb)
1512 		return NULL;
1513 
1514 	dev->cmb_dma_addr = dma_addr;
1515 	dev->cmb_size = size;
1516 	return cmb;
1517 }
1518 
1519 static inline void nvme_release_cmb(struct nvme_dev *dev)
1520 {
1521 	if (dev->cmb) {
1522 		iounmap(dev->cmb);
1523 		dev->cmb = NULL;
1524 		if (dev->cmbsz) {
1525 			sysfs_remove_file_from_group(&dev->ctrl.device->kobj,
1526 						     &dev_attr_cmb.attr, NULL);
1527 			dev->cmbsz = 0;
1528 		}
1529 	}
1530 }
1531 
1532 static int nvme_set_host_mem(struct nvme_dev *dev, u32 bits)
1533 {
1534 	size_t len = dev->nr_host_mem_descs * sizeof(*dev->host_mem_descs);
1535 	struct nvme_command c;
1536 	u64 dma_addr;
1537 	int ret;
1538 
1539 	dma_addr = dma_map_single(dev->dev, dev->host_mem_descs, len,
1540 			DMA_TO_DEVICE);
1541 	if (dma_mapping_error(dev->dev, dma_addr))
1542 		return -ENOMEM;
1543 
1544 	memset(&c, 0, sizeof(c));
1545 	c.features.opcode	= nvme_admin_set_features;
1546 	c.features.fid		= cpu_to_le32(NVME_FEAT_HOST_MEM_BUF);
1547 	c.features.dword11	= cpu_to_le32(bits);
1548 	c.features.dword12	= cpu_to_le32(dev->host_mem_size >>
1549 					      ilog2(dev->ctrl.page_size));
1550 	c.features.dword13	= cpu_to_le32(lower_32_bits(dma_addr));
1551 	c.features.dword14	= cpu_to_le32(upper_32_bits(dma_addr));
1552 	c.features.dword15	= cpu_to_le32(dev->nr_host_mem_descs);
1553 
1554 	ret = nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1555 	if (ret) {
1556 		dev_warn(dev->ctrl.device,
1557 			 "failed to set host mem (err %d, flags %#x).\n",
1558 			 ret, bits);
1559 	}
1560 	dma_unmap_single(dev->dev, dma_addr, len, DMA_TO_DEVICE);
1561 	return ret;
1562 }
1563 
1564 static void nvme_free_host_mem(struct nvme_dev *dev)
1565 {
1566 	int i;
1567 
1568 	for (i = 0; i < dev->nr_host_mem_descs; i++) {
1569 		struct nvme_host_mem_buf_desc *desc = &dev->host_mem_descs[i];
1570 		size_t size = le32_to_cpu(desc->size) * dev->ctrl.page_size;
1571 
1572 		dma_free_coherent(dev->dev, size, dev->host_mem_desc_bufs[i],
1573 				le64_to_cpu(desc->addr));
1574 	}
1575 
1576 	kfree(dev->host_mem_desc_bufs);
1577 	dev->host_mem_desc_bufs = NULL;
1578 	kfree(dev->host_mem_descs);
1579 	dev->host_mem_descs = NULL;
1580 }
1581 
1582 static int nvme_alloc_host_mem(struct nvme_dev *dev, u64 min, u64 preferred)
1583 {
1584 	struct nvme_host_mem_buf_desc *descs;
1585 	u32 chunk_size, max_entries, i = 0;
1586 	void **bufs;
1587 	u64 size, tmp;
1588 
1589 	/* start big and work our way down */
1590 	chunk_size = min(preferred, (u64)PAGE_SIZE << MAX_ORDER);
1591 retry:
1592 	tmp = (preferred + chunk_size - 1);
1593 	do_div(tmp, chunk_size);
1594 	max_entries = tmp;
1595 	descs = kcalloc(max_entries, sizeof(*descs), GFP_KERNEL);
1596 	if (!descs)
1597 		goto out;
1598 
1599 	bufs = kcalloc(max_entries, sizeof(*bufs), GFP_KERNEL);
1600 	if (!bufs)
1601 		goto out_free_descs;
1602 
1603 	for (size = 0; size < preferred; size += chunk_size) {
1604 		u32 len = min_t(u64, chunk_size, preferred - size);
1605 		dma_addr_t dma_addr;
1606 
1607 		bufs[i] = dma_alloc_attrs(dev->dev, len, &dma_addr, GFP_KERNEL,
1608 				DMA_ATTR_NO_KERNEL_MAPPING | DMA_ATTR_NO_WARN);
1609 		if (!bufs[i])
1610 			break;
1611 
1612 		descs[i].addr = cpu_to_le64(dma_addr);
1613 		descs[i].size = cpu_to_le32(len / dev->ctrl.page_size);
1614 		i++;
1615 	}
1616 
1617 	if (!size || (min && size < min)) {
1618 		dev_warn(dev->ctrl.device,
1619 			"failed to allocate host memory buffer.\n");
1620 		goto out_free_bufs;
1621 	}
1622 
1623 	dev_info(dev->ctrl.device,
1624 		"allocated %lld MiB host memory buffer.\n",
1625 		size >> ilog2(SZ_1M));
1626 	dev->nr_host_mem_descs = i;
1627 	dev->host_mem_size = size;
1628 	dev->host_mem_descs = descs;
1629 	dev->host_mem_desc_bufs = bufs;
1630 	return 0;
1631 
1632 out_free_bufs:
1633 	while (--i >= 0) {
1634 		size_t size = le32_to_cpu(descs[i].size) * dev->ctrl.page_size;
1635 
1636 		dma_free_coherent(dev->dev, size, bufs[i],
1637 				le64_to_cpu(descs[i].addr));
1638 	}
1639 
1640 	kfree(bufs);
1641 out_free_descs:
1642 	kfree(descs);
1643 out:
1644 	/* try a smaller chunk size if we failed early */
1645 	if (chunk_size >= PAGE_SIZE * 2 && (i == 0 || size < min)) {
1646 		chunk_size /= 2;
1647 		goto retry;
1648 	}
1649 	dev->host_mem_descs = NULL;
1650 	return -ENOMEM;
1651 }
1652 
1653 static void nvme_setup_host_mem(struct nvme_dev *dev)
1654 {
1655 	u64 max = (u64)max_host_mem_size_mb * SZ_1M;
1656 	u64 preferred = (u64)dev->ctrl.hmpre * 4096;
1657 	u64 min = (u64)dev->ctrl.hmmin * 4096;
1658 	u32 enable_bits = NVME_HOST_MEM_ENABLE;
1659 
1660 	preferred = min(preferred, max);
1661 	if (min > max) {
1662 		dev_warn(dev->ctrl.device,
1663 			"min host memory (%lld MiB) above limit (%d MiB).\n",
1664 			min >> ilog2(SZ_1M), max_host_mem_size_mb);
1665 		nvme_free_host_mem(dev);
1666 		return;
1667 	}
1668 
1669 	/*
1670 	 * If we already have a buffer allocated check if we can reuse it.
1671 	 */
1672 	if (dev->host_mem_descs) {
1673 		if (dev->host_mem_size >= min)
1674 			enable_bits |= NVME_HOST_MEM_RETURN;
1675 		else
1676 			nvme_free_host_mem(dev);
1677 	}
1678 
1679 	if (!dev->host_mem_descs) {
1680 		if (nvme_alloc_host_mem(dev, min, preferred))
1681 			return;
1682 	}
1683 
1684 	if (nvme_set_host_mem(dev, enable_bits))
1685 		nvme_free_host_mem(dev);
1686 }
1687 
1688 static int nvme_setup_io_queues(struct nvme_dev *dev)
1689 {
1690 	struct nvme_queue *adminq = dev->queues[0];
1691 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1692 	int result, nr_io_queues;
1693 	unsigned long size;
1694 
1695 	nr_io_queues = num_online_cpus();
1696 	result = nvme_set_queue_count(&dev->ctrl, &nr_io_queues);
1697 	if (result < 0)
1698 		return result;
1699 
1700 	if (nr_io_queues == 0)
1701 		return 0;
1702 
1703 	if (dev->cmb && NVME_CMB_SQS(dev->cmbsz)) {
1704 		result = nvme_cmb_qdepth(dev, nr_io_queues,
1705 				sizeof(struct nvme_command));
1706 		if (result > 0)
1707 			dev->q_depth = result;
1708 		else
1709 			nvme_release_cmb(dev);
1710 	}
1711 
1712 	do {
1713 		size = db_bar_size(dev, nr_io_queues);
1714 		result = nvme_remap_bar(dev, size);
1715 		if (!result)
1716 			break;
1717 		if (!--nr_io_queues)
1718 			return -ENOMEM;
1719 	} while (1);
1720 	adminq->q_db = dev->dbs;
1721 
1722 	/* Deregister the admin queue's interrupt */
1723 	pci_free_irq(pdev, 0, adminq);
1724 
1725 	/*
1726 	 * If we enable msix early due to not intx, disable it again before
1727 	 * setting up the full range we need.
1728 	 */
1729 	pci_free_irq_vectors(pdev);
1730 	nr_io_queues = pci_alloc_irq_vectors(pdev, 1, nr_io_queues,
1731 			PCI_IRQ_ALL_TYPES | PCI_IRQ_AFFINITY);
1732 	if (nr_io_queues <= 0)
1733 		return -EIO;
1734 	dev->max_qid = nr_io_queues;
1735 
1736 	/*
1737 	 * Should investigate if there's a performance win from allocating
1738 	 * more queues than interrupt vectors; it might allow the submission
1739 	 * path to scale better, even if the receive path is limited by the
1740 	 * number of interrupts.
1741 	 */
1742 
1743 	result = queue_request_irq(adminq);
1744 	if (result) {
1745 		adminq->cq_vector = -1;
1746 		return result;
1747 	}
1748 	return nvme_create_io_queues(dev);
1749 }
1750 
1751 static void nvme_del_queue_end(struct request *req, blk_status_t error)
1752 {
1753 	struct nvme_queue *nvmeq = req->end_io_data;
1754 
1755 	blk_mq_free_request(req);
1756 	complete(&nvmeq->dev->ioq_wait);
1757 }
1758 
1759 static void nvme_del_cq_end(struct request *req, blk_status_t error)
1760 {
1761 	struct nvme_queue *nvmeq = req->end_io_data;
1762 
1763 	if (!error) {
1764 		unsigned long flags;
1765 
1766 		/*
1767 		 * We might be called with the AQ q_lock held
1768 		 * and the I/O queue q_lock should always
1769 		 * nest inside the AQ one.
1770 		 */
1771 		spin_lock_irqsave_nested(&nvmeq->q_lock, flags,
1772 					SINGLE_DEPTH_NESTING);
1773 		nvme_process_cq(nvmeq);
1774 		spin_unlock_irqrestore(&nvmeq->q_lock, flags);
1775 	}
1776 
1777 	nvme_del_queue_end(req, error);
1778 }
1779 
1780 static int nvme_delete_queue(struct nvme_queue *nvmeq, u8 opcode)
1781 {
1782 	struct request_queue *q = nvmeq->dev->ctrl.admin_q;
1783 	struct request *req;
1784 	struct nvme_command cmd;
1785 
1786 	memset(&cmd, 0, sizeof(cmd));
1787 	cmd.delete_queue.opcode = opcode;
1788 	cmd.delete_queue.qid = cpu_to_le16(nvmeq->qid);
1789 
1790 	req = nvme_alloc_request(q, &cmd, BLK_MQ_REQ_NOWAIT, NVME_QID_ANY);
1791 	if (IS_ERR(req))
1792 		return PTR_ERR(req);
1793 
1794 	req->timeout = ADMIN_TIMEOUT;
1795 	req->end_io_data = nvmeq;
1796 
1797 	blk_execute_rq_nowait(q, NULL, req, false,
1798 			opcode == nvme_admin_delete_cq ?
1799 				nvme_del_cq_end : nvme_del_queue_end);
1800 	return 0;
1801 }
1802 
1803 static void nvme_disable_io_queues(struct nvme_dev *dev, int queues)
1804 {
1805 	int pass;
1806 	unsigned long timeout;
1807 	u8 opcode = nvme_admin_delete_sq;
1808 
1809 	for (pass = 0; pass < 2; pass++) {
1810 		int sent = 0, i = queues;
1811 
1812 		reinit_completion(&dev->ioq_wait);
1813  retry:
1814 		timeout = ADMIN_TIMEOUT;
1815 		for (; i > 0; i--, sent++)
1816 			if (nvme_delete_queue(dev->queues[i], opcode))
1817 				break;
1818 
1819 		while (sent--) {
1820 			timeout = wait_for_completion_io_timeout(&dev->ioq_wait, timeout);
1821 			if (timeout == 0)
1822 				return;
1823 			if (i)
1824 				goto retry;
1825 		}
1826 		opcode = nvme_admin_delete_cq;
1827 	}
1828 }
1829 
1830 /*
1831  * Return: error value if an error occurred setting up the queues or calling
1832  * Identify Device.  0 if these succeeded, even if adding some of the
1833  * namespaces failed.  At the moment, these failures are silent.  TBD which
1834  * failures should be reported.
1835  */
1836 static int nvme_dev_add(struct nvme_dev *dev)
1837 {
1838 	if (!dev->ctrl.tagset) {
1839 		dev->tagset.ops = &nvme_mq_ops;
1840 		dev->tagset.nr_hw_queues = dev->online_queues - 1;
1841 		dev->tagset.timeout = NVME_IO_TIMEOUT;
1842 		dev->tagset.numa_node = dev_to_node(dev->dev);
1843 		dev->tagset.queue_depth =
1844 				min_t(int, dev->q_depth, BLK_MQ_MAX_DEPTH) - 1;
1845 		dev->tagset.cmd_size = nvme_cmd_size(dev);
1846 		dev->tagset.flags = BLK_MQ_F_SHOULD_MERGE;
1847 		dev->tagset.driver_data = dev;
1848 
1849 		if (blk_mq_alloc_tag_set(&dev->tagset))
1850 			return 0;
1851 		dev->ctrl.tagset = &dev->tagset;
1852 
1853 		nvme_dbbuf_set(dev);
1854 	} else {
1855 		blk_mq_update_nr_hw_queues(&dev->tagset, dev->online_queues - 1);
1856 
1857 		/* Free previously allocated queues that are no longer usable */
1858 		nvme_free_queues(dev, dev->online_queues);
1859 	}
1860 
1861 	return 0;
1862 }
1863 
1864 static int nvme_pci_enable(struct nvme_dev *dev)
1865 {
1866 	int result = -ENOMEM;
1867 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1868 
1869 	if (pci_enable_device_mem(pdev))
1870 		return result;
1871 
1872 	pci_set_master(pdev);
1873 
1874 	if (dma_set_mask_and_coherent(dev->dev, DMA_BIT_MASK(64)) &&
1875 	    dma_set_mask_and_coherent(dev->dev, DMA_BIT_MASK(32)))
1876 		goto disable;
1877 
1878 	if (readl(dev->bar + NVME_REG_CSTS) == -1) {
1879 		result = -ENODEV;
1880 		goto disable;
1881 	}
1882 
1883 	/*
1884 	 * Some devices and/or platforms don't advertise or work with INTx
1885 	 * interrupts. Pre-enable a single MSIX or MSI vec for setup. We'll
1886 	 * adjust this later.
1887 	 */
1888 	result = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
1889 	if (result < 0)
1890 		return result;
1891 
1892 	dev->ctrl.cap = lo_hi_readq(dev->bar + NVME_REG_CAP);
1893 
1894 	dev->q_depth = min_t(int, NVME_CAP_MQES(dev->ctrl.cap) + 1,
1895 				NVME_Q_DEPTH);
1896 	dev->db_stride = 1 << NVME_CAP_STRIDE(dev->ctrl.cap);
1897 	dev->dbs = dev->bar + 4096;
1898 
1899 	/*
1900 	 * Temporary fix for the Apple controller found in the MacBook8,1 and
1901 	 * some MacBook7,1 to avoid controller resets and data loss.
1902 	 */
1903 	if (pdev->vendor == PCI_VENDOR_ID_APPLE && pdev->device == 0x2001) {
1904 		dev->q_depth = 2;
1905 		dev_warn(dev->ctrl.device, "detected Apple NVMe controller, "
1906 			"set queue depth=%u to work around controller resets\n",
1907 			dev->q_depth);
1908 	} else if (pdev->vendor == PCI_VENDOR_ID_SAMSUNG &&
1909 		   (pdev->device == 0xa821 || pdev->device == 0xa822) &&
1910 		   NVME_CAP_MQES(dev->ctrl.cap) == 0) {
1911 		dev->q_depth = 64;
1912 		dev_err(dev->ctrl.device, "detected PM1725 NVMe controller, "
1913                         "set queue depth=%u\n", dev->q_depth);
1914 	}
1915 
1916 	/*
1917 	 * CMBs can currently only exist on >=1.2 PCIe devices. We only
1918 	 * populate sysfs if a CMB is implemented. Note that we add the
1919 	 * CMB attribute to the nvme_ctrl kobj which removes the need to remove
1920 	 * it on exit. Since nvme_dev_attrs_group has no name we can pass
1921 	 * NULL as final argument to sysfs_add_file_to_group.
1922 	 */
1923 
1924 	if (readl(dev->bar + NVME_REG_VS) >= NVME_VS(1, 2, 0)) {
1925 		dev->cmb = nvme_map_cmb(dev);
1926 
1927 		if (dev->cmbsz) {
1928 			if (sysfs_add_file_to_group(&dev->ctrl.device->kobj,
1929 						    &dev_attr_cmb.attr, NULL))
1930 				dev_warn(dev->ctrl.device,
1931 					 "failed to add sysfs attribute for CMB\n");
1932 		}
1933 	}
1934 
1935 	pci_enable_pcie_error_reporting(pdev);
1936 	pci_save_state(pdev);
1937 	return 0;
1938 
1939  disable:
1940 	pci_disable_device(pdev);
1941 	return result;
1942 }
1943 
1944 static void nvme_dev_unmap(struct nvme_dev *dev)
1945 {
1946 	if (dev->bar)
1947 		iounmap(dev->bar);
1948 	pci_release_mem_regions(to_pci_dev(dev->dev));
1949 }
1950 
1951 static void nvme_pci_disable(struct nvme_dev *dev)
1952 {
1953 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1954 
1955 	nvme_release_cmb(dev);
1956 	pci_free_irq_vectors(pdev);
1957 
1958 	if (pci_is_enabled(pdev)) {
1959 		pci_disable_pcie_error_reporting(pdev);
1960 		pci_disable_device(pdev);
1961 	}
1962 }
1963 
1964 static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown)
1965 {
1966 	int i, queues;
1967 	bool dead = true;
1968 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1969 
1970 	mutex_lock(&dev->shutdown_lock);
1971 	if (pci_is_enabled(pdev)) {
1972 		u32 csts = readl(dev->bar + NVME_REG_CSTS);
1973 
1974 		if (dev->ctrl.state == NVME_CTRL_LIVE)
1975 			nvme_start_freeze(&dev->ctrl);
1976 		dead = !!((csts & NVME_CSTS_CFS) || !(csts & NVME_CSTS_RDY) ||
1977 			pdev->error_state  != pci_channel_io_normal);
1978 	}
1979 
1980 	/*
1981 	 * Give the controller a chance to complete all entered requests if
1982 	 * doing a safe shutdown.
1983 	 */
1984 	if (!dead) {
1985 		if (shutdown)
1986 			nvme_wait_freeze_timeout(&dev->ctrl, NVME_IO_TIMEOUT);
1987 
1988 		/*
1989 		 * If the controller is still alive tell it to stop using the
1990 		 * host memory buffer.  In theory the shutdown / reset should
1991 		 * make sure that it doesn't access the host memoery anymore,
1992 		 * but I'd rather be safe than sorry..
1993 		 */
1994 		if (dev->host_mem_descs)
1995 			nvme_set_host_mem(dev, 0);
1996 
1997 	}
1998 	nvme_stop_queues(&dev->ctrl);
1999 
2000 	queues = dev->online_queues - 1;
2001 	for (i = dev->ctrl.queue_count - 1; i > 0; i--)
2002 		nvme_suspend_queue(dev->queues[i]);
2003 
2004 	if (dead) {
2005 		/* A device might become IO incapable very soon during
2006 		 * probe, before the admin queue is configured. Thus,
2007 		 * queue_count can be 0 here.
2008 		 */
2009 		if (dev->ctrl.queue_count)
2010 			nvme_suspend_queue(dev->queues[0]);
2011 	} else {
2012 		nvme_disable_io_queues(dev, queues);
2013 		nvme_disable_admin_queue(dev, shutdown);
2014 	}
2015 	nvme_pci_disable(dev);
2016 
2017 	blk_mq_tagset_busy_iter(&dev->tagset, nvme_cancel_request, &dev->ctrl);
2018 	blk_mq_tagset_busy_iter(&dev->admin_tagset, nvme_cancel_request, &dev->ctrl);
2019 
2020 	/*
2021 	 * The driver will not be starting up queues again if shutting down so
2022 	 * must flush all entered requests to their failed completion to avoid
2023 	 * deadlocking blk-mq hot-cpu notifier.
2024 	 */
2025 	if (shutdown)
2026 		nvme_start_queues(&dev->ctrl);
2027 	mutex_unlock(&dev->shutdown_lock);
2028 }
2029 
2030 static int nvme_setup_prp_pools(struct nvme_dev *dev)
2031 {
2032 	dev->prp_page_pool = dma_pool_create("prp list page", dev->dev,
2033 						PAGE_SIZE, PAGE_SIZE, 0);
2034 	if (!dev->prp_page_pool)
2035 		return -ENOMEM;
2036 
2037 	/* Optimisation for I/Os between 4k and 128k */
2038 	dev->prp_small_pool = dma_pool_create("prp list 256", dev->dev,
2039 						256, 256, 0);
2040 	if (!dev->prp_small_pool) {
2041 		dma_pool_destroy(dev->prp_page_pool);
2042 		return -ENOMEM;
2043 	}
2044 	return 0;
2045 }
2046 
2047 static void nvme_release_prp_pools(struct nvme_dev *dev)
2048 {
2049 	dma_pool_destroy(dev->prp_page_pool);
2050 	dma_pool_destroy(dev->prp_small_pool);
2051 }
2052 
2053 static void nvme_pci_free_ctrl(struct nvme_ctrl *ctrl)
2054 {
2055 	struct nvme_dev *dev = to_nvme_dev(ctrl);
2056 
2057 	nvme_dbbuf_dma_free(dev);
2058 	put_device(dev->dev);
2059 	if (dev->tagset.tags)
2060 		blk_mq_free_tag_set(&dev->tagset);
2061 	if (dev->ctrl.admin_q)
2062 		blk_put_queue(dev->ctrl.admin_q);
2063 	kfree(dev->queues);
2064 	free_opal_dev(dev->ctrl.opal_dev);
2065 	kfree(dev);
2066 }
2067 
2068 static void nvme_remove_dead_ctrl(struct nvme_dev *dev, int status)
2069 {
2070 	dev_warn(dev->ctrl.device, "Removing after probe failure status: %d\n", status);
2071 
2072 	kref_get(&dev->ctrl.kref);
2073 	nvme_dev_disable(dev, false);
2074 	if (!schedule_work(&dev->remove_work))
2075 		nvme_put_ctrl(&dev->ctrl);
2076 }
2077 
2078 static void nvme_reset_work(struct work_struct *work)
2079 {
2080 	struct nvme_dev *dev =
2081 		container_of(work, struct nvme_dev, ctrl.reset_work);
2082 	bool was_suspend = !!(dev->ctrl.ctrl_config & NVME_CC_SHN_NORMAL);
2083 	int result = -ENODEV;
2084 
2085 	if (WARN_ON(dev->ctrl.state != NVME_CTRL_RESETTING))
2086 		goto out;
2087 
2088 	/*
2089 	 * If we're called to reset a live controller first shut it down before
2090 	 * moving on.
2091 	 */
2092 	if (dev->ctrl.ctrl_config & NVME_CC_ENABLE)
2093 		nvme_dev_disable(dev, false);
2094 
2095 	result = nvme_pci_enable(dev);
2096 	if (result)
2097 		goto out;
2098 
2099 	result = nvme_pci_configure_admin_queue(dev);
2100 	if (result)
2101 		goto out;
2102 
2103 	nvme_init_queue(dev->queues[0], 0);
2104 	result = nvme_alloc_admin_tags(dev);
2105 	if (result)
2106 		goto out;
2107 
2108 	result = nvme_init_identify(&dev->ctrl);
2109 	if (result)
2110 		goto out;
2111 
2112 	if (dev->ctrl.oacs & NVME_CTRL_OACS_SEC_SUPP) {
2113 		if (!dev->ctrl.opal_dev)
2114 			dev->ctrl.opal_dev =
2115 				init_opal_dev(&dev->ctrl, &nvme_sec_submit);
2116 		else if (was_suspend)
2117 			opal_unlock_from_suspend(dev->ctrl.opal_dev);
2118 	} else {
2119 		free_opal_dev(dev->ctrl.opal_dev);
2120 		dev->ctrl.opal_dev = NULL;
2121 	}
2122 
2123 	if (dev->ctrl.oacs & NVME_CTRL_OACS_DBBUF_SUPP) {
2124 		result = nvme_dbbuf_dma_alloc(dev);
2125 		if (result)
2126 			dev_warn(dev->dev,
2127 				 "unable to allocate dma for dbbuf\n");
2128 	}
2129 
2130 	if (dev->ctrl.hmpre)
2131 		nvme_setup_host_mem(dev);
2132 
2133 	result = nvme_setup_io_queues(dev);
2134 	if (result)
2135 		goto out;
2136 
2137 	/*
2138 	 * A controller that can not execute IO typically requires user
2139 	 * intervention to correct. For such degraded controllers, the driver
2140 	 * should not submit commands the user did not request, so skip
2141 	 * registering for asynchronous event notification on this condition.
2142 	 */
2143 	if (dev->online_queues > 1)
2144 		nvme_queue_async_events(&dev->ctrl);
2145 
2146 	/*
2147 	 * Keep the controller around but remove all namespaces if we don't have
2148 	 * any working I/O queue.
2149 	 */
2150 	if (dev->online_queues < 2) {
2151 		dev_warn(dev->ctrl.device, "IO queues not created\n");
2152 		nvme_kill_queues(&dev->ctrl);
2153 		nvme_remove_namespaces(&dev->ctrl);
2154 	} else {
2155 		nvme_start_queues(&dev->ctrl);
2156 		nvme_wait_freeze(&dev->ctrl);
2157 		nvme_dev_add(dev);
2158 		nvme_unfreeze(&dev->ctrl);
2159 	}
2160 
2161 	if (!nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_LIVE)) {
2162 		dev_warn(dev->ctrl.device, "failed to mark controller live\n");
2163 		goto out;
2164 	}
2165 
2166 	if (dev->online_queues > 1)
2167 		nvme_queue_scan(&dev->ctrl);
2168 	return;
2169 
2170  out:
2171 	nvme_remove_dead_ctrl(dev, result);
2172 }
2173 
2174 static void nvme_remove_dead_ctrl_work(struct work_struct *work)
2175 {
2176 	struct nvme_dev *dev = container_of(work, struct nvme_dev, remove_work);
2177 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2178 
2179 	nvme_kill_queues(&dev->ctrl);
2180 	if (pci_get_drvdata(pdev))
2181 		device_release_driver(&pdev->dev);
2182 	nvme_put_ctrl(&dev->ctrl);
2183 }
2184 
2185 static int nvme_pci_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val)
2186 {
2187 	*val = readl(to_nvme_dev(ctrl)->bar + off);
2188 	return 0;
2189 }
2190 
2191 static int nvme_pci_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val)
2192 {
2193 	writel(val, to_nvme_dev(ctrl)->bar + off);
2194 	return 0;
2195 }
2196 
2197 static int nvme_pci_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val)
2198 {
2199 	*val = readq(to_nvme_dev(ctrl)->bar + off);
2200 	return 0;
2201 }
2202 
2203 static const struct nvme_ctrl_ops nvme_pci_ctrl_ops = {
2204 	.name			= "pcie",
2205 	.module			= THIS_MODULE,
2206 	.flags			= NVME_F_METADATA_SUPPORTED,
2207 	.reg_read32		= nvme_pci_reg_read32,
2208 	.reg_write32		= nvme_pci_reg_write32,
2209 	.reg_read64		= nvme_pci_reg_read64,
2210 	.free_ctrl		= nvme_pci_free_ctrl,
2211 	.submit_async_event	= nvme_pci_submit_async_event,
2212 };
2213 
2214 static int nvme_dev_map(struct nvme_dev *dev)
2215 {
2216 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2217 
2218 	if (pci_request_mem_regions(pdev, "nvme"))
2219 		return -ENODEV;
2220 
2221 	if (nvme_remap_bar(dev, NVME_REG_DBS + 4096))
2222 		goto release;
2223 
2224 	return 0;
2225   release:
2226 	pci_release_mem_regions(pdev);
2227 	return -ENODEV;
2228 }
2229 
2230 static unsigned long check_dell_samsung_bug(struct pci_dev *pdev)
2231 {
2232 	if (pdev->vendor == 0x144d && pdev->device == 0xa802) {
2233 		/*
2234 		 * Several Samsung devices seem to drop off the PCIe bus
2235 		 * randomly when APST is on and uses the deepest sleep state.
2236 		 * This has been observed on a Samsung "SM951 NVMe SAMSUNG
2237 		 * 256GB", a "PM951 NVMe SAMSUNG 512GB", and a "Samsung SSD
2238 		 * 950 PRO 256GB", but it seems to be restricted to two Dell
2239 		 * laptops.
2240 		 */
2241 		if (dmi_match(DMI_SYS_VENDOR, "Dell Inc.") &&
2242 		    (dmi_match(DMI_PRODUCT_NAME, "XPS 15 9550") ||
2243 		     dmi_match(DMI_PRODUCT_NAME, "Precision 5510")))
2244 			return NVME_QUIRK_NO_DEEPEST_PS;
2245 	}
2246 
2247 	return 0;
2248 }
2249 
2250 static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
2251 {
2252 	int node, result = -ENOMEM;
2253 	struct nvme_dev *dev;
2254 	unsigned long quirks = id->driver_data;
2255 
2256 	node = dev_to_node(&pdev->dev);
2257 	if (node == NUMA_NO_NODE)
2258 		set_dev_node(&pdev->dev, first_memory_node);
2259 
2260 	dev = kzalloc_node(sizeof(*dev), GFP_KERNEL, node);
2261 	if (!dev)
2262 		return -ENOMEM;
2263 	dev->queues = kzalloc_node((num_possible_cpus() + 1) * sizeof(void *),
2264 							GFP_KERNEL, node);
2265 	if (!dev->queues)
2266 		goto free;
2267 
2268 	dev->dev = get_device(&pdev->dev);
2269 	pci_set_drvdata(pdev, dev);
2270 
2271 	result = nvme_dev_map(dev);
2272 	if (result)
2273 		goto free;
2274 
2275 	INIT_WORK(&dev->ctrl.reset_work, nvme_reset_work);
2276 	INIT_WORK(&dev->remove_work, nvme_remove_dead_ctrl_work);
2277 	mutex_init(&dev->shutdown_lock);
2278 	init_completion(&dev->ioq_wait);
2279 
2280 	result = nvme_setup_prp_pools(dev);
2281 	if (result)
2282 		goto put_pci;
2283 
2284 	quirks |= check_dell_samsung_bug(pdev);
2285 
2286 	result = nvme_init_ctrl(&dev->ctrl, &pdev->dev, &nvme_pci_ctrl_ops,
2287 			quirks);
2288 	if (result)
2289 		goto release_pools;
2290 
2291 	nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_RESETTING);
2292 	dev_info(dev->ctrl.device, "pci function %s\n", dev_name(&pdev->dev));
2293 
2294 	queue_work(nvme_wq, &dev->ctrl.reset_work);
2295 	return 0;
2296 
2297  release_pools:
2298 	nvme_release_prp_pools(dev);
2299  put_pci:
2300 	put_device(dev->dev);
2301 	nvme_dev_unmap(dev);
2302  free:
2303 	kfree(dev->queues);
2304 	kfree(dev);
2305 	return result;
2306 }
2307 
2308 static void nvme_reset_notify(struct pci_dev *pdev, bool prepare)
2309 {
2310 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2311 
2312 	if (prepare)
2313 		nvme_dev_disable(dev, false);
2314 	else
2315 		nvme_reset_ctrl(&dev->ctrl);
2316 }
2317 
2318 static void nvme_shutdown(struct pci_dev *pdev)
2319 {
2320 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2321 	nvme_dev_disable(dev, true);
2322 }
2323 
2324 /*
2325  * The driver's remove may be called on a device in a partially initialized
2326  * state. This function must not have any dependencies on the device state in
2327  * order to proceed.
2328  */
2329 static void nvme_remove(struct pci_dev *pdev)
2330 {
2331 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2332 
2333 	nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DELETING);
2334 
2335 	cancel_work_sync(&dev->ctrl.reset_work);
2336 	pci_set_drvdata(pdev, NULL);
2337 
2338 	if (!pci_device_is_present(pdev)) {
2339 		nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DEAD);
2340 		nvme_dev_disable(dev, false);
2341 	}
2342 
2343 	flush_work(&dev->ctrl.reset_work);
2344 	nvme_uninit_ctrl(&dev->ctrl);
2345 	nvme_dev_disable(dev, true);
2346 	nvme_free_host_mem(dev);
2347 	nvme_dev_remove_admin(dev);
2348 	nvme_free_queues(dev, 0);
2349 	nvme_release_prp_pools(dev);
2350 	nvme_dev_unmap(dev);
2351 	nvme_put_ctrl(&dev->ctrl);
2352 }
2353 
2354 static int nvme_pci_sriov_configure(struct pci_dev *pdev, int numvfs)
2355 {
2356 	int ret = 0;
2357 
2358 	if (numvfs == 0) {
2359 		if (pci_vfs_assigned(pdev)) {
2360 			dev_warn(&pdev->dev,
2361 				"Cannot disable SR-IOV VFs while assigned\n");
2362 			return -EPERM;
2363 		}
2364 		pci_disable_sriov(pdev);
2365 		return 0;
2366 	}
2367 
2368 	ret = pci_enable_sriov(pdev, numvfs);
2369 	return ret ? ret : numvfs;
2370 }
2371 
2372 #ifdef CONFIG_PM_SLEEP
2373 static int nvme_suspend(struct device *dev)
2374 {
2375 	struct pci_dev *pdev = to_pci_dev(dev);
2376 	struct nvme_dev *ndev = pci_get_drvdata(pdev);
2377 
2378 	nvme_dev_disable(ndev, true);
2379 	return 0;
2380 }
2381 
2382 static int nvme_resume(struct device *dev)
2383 {
2384 	struct pci_dev *pdev = to_pci_dev(dev);
2385 	struct nvme_dev *ndev = pci_get_drvdata(pdev);
2386 
2387 	nvme_reset_ctrl(&ndev->ctrl);
2388 	return 0;
2389 }
2390 #endif
2391 
2392 static SIMPLE_DEV_PM_OPS(nvme_dev_pm_ops, nvme_suspend, nvme_resume);
2393 
2394 static pci_ers_result_t nvme_error_detected(struct pci_dev *pdev,
2395 						pci_channel_state_t state)
2396 {
2397 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2398 
2399 	/*
2400 	 * A frozen channel requires a reset. When detected, this method will
2401 	 * shutdown the controller to quiesce. The controller will be restarted
2402 	 * after the slot reset through driver's slot_reset callback.
2403 	 */
2404 	switch (state) {
2405 	case pci_channel_io_normal:
2406 		return PCI_ERS_RESULT_CAN_RECOVER;
2407 	case pci_channel_io_frozen:
2408 		dev_warn(dev->ctrl.device,
2409 			"frozen state error detected, reset controller\n");
2410 		nvme_dev_disable(dev, false);
2411 		return PCI_ERS_RESULT_NEED_RESET;
2412 	case pci_channel_io_perm_failure:
2413 		dev_warn(dev->ctrl.device,
2414 			"failure state error detected, request disconnect\n");
2415 		return PCI_ERS_RESULT_DISCONNECT;
2416 	}
2417 	return PCI_ERS_RESULT_NEED_RESET;
2418 }
2419 
2420 static pci_ers_result_t nvme_slot_reset(struct pci_dev *pdev)
2421 {
2422 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2423 
2424 	dev_info(dev->ctrl.device, "restart after slot reset\n");
2425 	pci_restore_state(pdev);
2426 	nvme_reset_ctrl(&dev->ctrl);
2427 	return PCI_ERS_RESULT_RECOVERED;
2428 }
2429 
2430 static void nvme_error_resume(struct pci_dev *pdev)
2431 {
2432 	pci_cleanup_aer_uncorrect_error_status(pdev);
2433 }
2434 
2435 static const struct pci_error_handlers nvme_err_handler = {
2436 	.error_detected	= nvme_error_detected,
2437 	.slot_reset	= nvme_slot_reset,
2438 	.resume		= nvme_error_resume,
2439 	.reset_notify	= nvme_reset_notify,
2440 };
2441 
2442 static const struct pci_device_id nvme_id_table[] = {
2443 	{ PCI_VDEVICE(INTEL, 0x0953),
2444 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
2445 				NVME_QUIRK_DEALLOCATE_ZEROES, },
2446 	{ PCI_VDEVICE(INTEL, 0x0a53),
2447 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
2448 				NVME_QUIRK_DEALLOCATE_ZEROES, },
2449 	{ PCI_VDEVICE(INTEL, 0x0a54),
2450 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
2451 				NVME_QUIRK_DEALLOCATE_ZEROES, },
2452 	{ PCI_VDEVICE(INTEL, 0xf1a5),	/* Intel 600P/P3100 */
2453 		.driver_data = NVME_QUIRK_NO_DEEPEST_PS },
2454 	{ PCI_VDEVICE(INTEL, 0x5845),	/* Qemu emulated controller */
2455 		.driver_data = NVME_QUIRK_IDENTIFY_CNS, },
2456 	{ PCI_DEVICE(0x1c58, 0x0003),	/* HGST adapter */
2457 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2458 	{ PCI_DEVICE(0x1c5f, 0x0540),	/* Memblaze Pblaze4 adapter */
2459 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2460 	{ PCI_DEVICE(0x144d, 0xa821),   /* Samsung PM1725 */
2461 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2462 	{ PCI_DEVICE(0x144d, 0xa822),   /* Samsung PM1725a */
2463 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2464 	{ PCI_DEVICE_CLASS(PCI_CLASS_STORAGE_EXPRESS, 0xffffff) },
2465 	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2001) },
2466 	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2003) },
2467 	{ 0, }
2468 };
2469 MODULE_DEVICE_TABLE(pci, nvme_id_table);
2470 
2471 static struct pci_driver nvme_driver = {
2472 	.name		= "nvme",
2473 	.id_table	= nvme_id_table,
2474 	.probe		= nvme_probe,
2475 	.remove		= nvme_remove,
2476 	.shutdown	= nvme_shutdown,
2477 	.driver		= {
2478 		.pm	= &nvme_dev_pm_ops,
2479 	},
2480 	.sriov_configure = nvme_pci_sriov_configure,
2481 	.err_handler	= &nvme_err_handler,
2482 };
2483 
2484 static int __init nvme_init(void)
2485 {
2486 	return pci_register_driver(&nvme_driver);
2487 }
2488 
2489 static void __exit nvme_exit(void)
2490 {
2491 	pci_unregister_driver(&nvme_driver);
2492 	_nvme_check_size();
2493 }
2494 
2495 MODULE_AUTHOR("Matthew Wilcox <willy@linux.intel.com>");
2496 MODULE_LICENSE("GPL");
2497 MODULE_VERSION("1.0");
2498 module_init(nvme_init);
2499 module_exit(nvme_exit);
2500