xref: /linux/drivers/nvme/host/pci.c (revision 26b433d0da062d6e19d75350c0171d3cf8ff560d)
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 SQ_SIZE(depth)		(depth * sizeof(struct nvme_command))
39 #define CQ_SIZE(depth)		(depth * sizeof(struct nvme_completion))
40 
41 /*
42  * We handle AEN commands ourselves and don't even let the
43  * block layer know about them.
44  */
45 #define NVME_AQ_BLKMQ_DEPTH	(NVME_AQ_DEPTH - NVME_NR_AERS)
46 
47 static int use_threaded_interrupts;
48 module_param(use_threaded_interrupts, int, 0);
49 
50 static bool use_cmb_sqes = true;
51 module_param(use_cmb_sqes, bool, 0644);
52 MODULE_PARM_DESC(use_cmb_sqes, "use controller's memory buffer for I/O SQes");
53 
54 static unsigned int max_host_mem_size_mb = 128;
55 module_param(max_host_mem_size_mb, uint, 0444);
56 MODULE_PARM_DESC(max_host_mem_size_mb,
57 	"Maximum Host Memory Buffer (HMB) size per controller (in MiB)");
58 
59 static int io_queue_depth_set(const char *val, const struct kernel_param *kp);
60 static const struct kernel_param_ops io_queue_depth_ops = {
61 	.set = io_queue_depth_set,
62 	.get = param_get_int,
63 };
64 
65 static int io_queue_depth = 1024;
66 module_param_cb(io_queue_depth, &io_queue_depth_ops, &io_queue_depth, 0644);
67 MODULE_PARM_DESC(io_queue_depth, "set io queue depth, should >= 2");
68 
69 struct nvme_dev;
70 struct nvme_queue;
71 
72 static void nvme_process_cq(struct nvme_queue *nvmeq);
73 static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown);
74 
75 /*
76  * Represents an NVM Express device.  Each nvme_dev is a PCI function.
77  */
78 struct nvme_dev {
79 	struct nvme_queue **queues;
80 	struct blk_mq_tag_set tagset;
81 	struct blk_mq_tag_set admin_tagset;
82 	u32 __iomem *dbs;
83 	struct device *dev;
84 	struct dma_pool *prp_page_pool;
85 	struct dma_pool *prp_small_pool;
86 	unsigned online_queues;
87 	unsigned max_qid;
88 	int q_depth;
89 	u32 db_stride;
90 	void __iomem *bar;
91 	unsigned long bar_mapped_size;
92 	struct work_struct remove_work;
93 	struct mutex shutdown_lock;
94 	bool subsystem;
95 	void __iomem *cmb;
96 	dma_addr_t cmb_dma_addr;
97 	u64 cmb_size;
98 	u32 cmbsz;
99 	u32 cmbloc;
100 	struct nvme_ctrl ctrl;
101 	struct completion ioq_wait;
102 
103 	/* shadow doorbell buffer support: */
104 	u32 *dbbuf_dbs;
105 	dma_addr_t dbbuf_dbs_dma_addr;
106 	u32 *dbbuf_eis;
107 	dma_addr_t dbbuf_eis_dma_addr;
108 
109 	/* host memory buffer support: */
110 	u64 host_mem_size;
111 	u32 nr_host_mem_descs;
112 	dma_addr_t host_mem_descs_dma;
113 	struct nvme_host_mem_buf_desc *host_mem_descs;
114 	void **host_mem_desc_bufs;
115 };
116 
117 static int io_queue_depth_set(const char *val, const struct kernel_param *kp)
118 {
119 	int n = 0, ret;
120 
121 	ret = kstrtoint(val, 10, &n);
122 	if (ret != 0 || n < 2)
123 		return -EINVAL;
124 
125 	return param_set_int(val, kp);
126 }
127 
128 static inline unsigned int sq_idx(unsigned int qid, u32 stride)
129 {
130 	return qid * 2 * stride;
131 }
132 
133 static inline unsigned int cq_idx(unsigned int qid, u32 stride)
134 {
135 	return (qid * 2 + 1) * stride;
136 }
137 
138 static inline struct nvme_dev *to_nvme_dev(struct nvme_ctrl *ctrl)
139 {
140 	return container_of(ctrl, struct nvme_dev, ctrl);
141 }
142 
143 /*
144  * An NVM Express queue.  Each device has at least two (one for admin
145  * commands and one for I/O commands).
146  */
147 struct nvme_queue {
148 	struct device *q_dmadev;
149 	struct nvme_dev *dev;
150 	spinlock_t q_lock;
151 	struct nvme_command *sq_cmds;
152 	struct nvme_command __iomem *sq_cmds_io;
153 	volatile struct nvme_completion *cqes;
154 	struct blk_mq_tags **tags;
155 	dma_addr_t sq_dma_addr;
156 	dma_addr_t cq_dma_addr;
157 	u32 __iomem *q_db;
158 	u16 q_depth;
159 	s16 cq_vector;
160 	u16 sq_tail;
161 	u16 cq_head;
162 	u16 qid;
163 	u8 cq_phase;
164 	u8 cqe_seen;
165 	u32 *dbbuf_sq_db;
166 	u32 *dbbuf_cq_db;
167 	u32 *dbbuf_sq_ei;
168 	u32 *dbbuf_cq_ei;
169 };
170 
171 /*
172  * The nvme_iod describes the data in an I/O, including the list of PRP
173  * entries.  You can't see it in this data structure because C doesn't let
174  * me express that.  Use nvme_init_iod to ensure there's enough space
175  * allocated to store the PRP list.
176  */
177 struct nvme_iod {
178 	struct nvme_request req;
179 	struct nvme_queue *nvmeq;
180 	int aborted;
181 	int npages;		/* In the PRP list. 0 means small pool in use */
182 	int nents;		/* Used in scatterlist */
183 	int length;		/* Of data, in bytes */
184 	dma_addr_t first_dma;
185 	struct scatterlist meta_sg; /* metadata requires single contiguous buffer */
186 	struct scatterlist *sg;
187 	struct scatterlist inline_sg[0];
188 };
189 
190 /*
191  * Check we didin't inadvertently grow the command struct
192  */
193 static inline void _nvme_check_size(void)
194 {
195 	BUILD_BUG_ON(sizeof(struct nvme_rw_command) != 64);
196 	BUILD_BUG_ON(sizeof(struct nvme_create_cq) != 64);
197 	BUILD_BUG_ON(sizeof(struct nvme_create_sq) != 64);
198 	BUILD_BUG_ON(sizeof(struct nvme_delete_queue) != 64);
199 	BUILD_BUG_ON(sizeof(struct nvme_features) != 64);
200 	BUILD_BUG_ON(sizeof(struct nvme_format_cmd) != 64);
201 	BUILD_BUG_ON(sizeof(struct nvme_abort_cmd) != 64);
202 	BUILD_BUG_ON(sizeof(struct nvme_command) != 64);
203 	BUILD_BUG_ON(sizeof(struct nvme_id_ctrl) != NVME_IDENTIFY_DATA_SIZE);
204 	BUILD_BUG_ON(sizeof(struct nvme_id_ns) != NVME_IDENTIFY_DATA_SIZE);
205 	BUILD_BUG_ON(sizeof(struct nvme_lba_range_type) != 64);
206 	BUILD_BUG_ON(sizeof(struct nvme_smart_log) != 512);
207 	BUILD_BUG_ON(sizeof(struct nvme_dbbuf) != 64);
208 }
209 
210 static inline unsigned int nvme_dbbuf_size(u32 stride)
211 {
212 	return ((num_possible_cpus() + 1) * 8 * stride);
213 }
214 
215 static int nvme_dbbuf_dma_alloc(struct nvme_dev *dev)
216 {
217 	unsigned int mem_size = nvme_dbbuf_size(dev->db_stride);
218 
219 	if (dev->dbbuf_dbs)
220 		return 0;
221 
222 	dev->dbbuf_dbs = dma_alloc_coherent(dev->dev, mem_size,
223 					    &dev->dbbuf_dbs_dma_addr,
224 					    GFP_KERNEL);
225 	if (!dev->dbbuf_dbs)
226 		return -ENOMEM;
227 	dev->dbbuf_eis = dma_alloc_coherent(dev->dev, mem_size,
228 					    &dev->dbbuf_eis_dma_addr,
229 					    GFP_KERNEL);
230 	if (!dev->dbbuf_eis) {
231 		dma_free_coherent(dev->dev, mem_size,
232 				  dev->dbbuf_dbs, dev->dbbuf_dbs_dma_addr);
233 		dev->dbbuf_dbs = NULL;
234 		return -ENOMEM;
235 	}
236 
237 	return 0;
238 }
239 
240 static void nvme_dbbuf_dma_free(struct nvme_dev *dev)
241 {
242 	unsigned int mem_size = nvme_dbbuf_size(dev->db_stride);
243 
244 	if (dev->dbbuf_dbs) {
245 		dma_free_coherent(dev->dev, mem_size,
246 				  dev->dbbuf_dbs, dev->dbbuf_dbs_dma_addr);
247 		dev->dbbuf_dbs = NULL;
248 	}
249 	if (dev->dbbuf_eis) {
250 		dma_free_coherent(dev->dev, mem_size,
251 				  dev->dbbuf_eis, dev->dbbuf_eis_dma_addr);
252 		dev->dbbuf_eis = NULL;
253 	}
254 }
255 
256 static void nvme_dbbuf_init(struct nvme_dev *dev,
257 			    struct nvme_queue *nvmeq, int qid)
258 {
259 	if (!dev->dbbuf_dbs || !qid)
260 		return;
261 
262 	nvmeq->dbbuf_sq_db = &dev->dbbuf_dbs[sq_idx(qid, dev->db_stride)];
263 	nvmeq->dbbuf_cq_db = &dev->dbbuf_dbs[cq_idx(qid, dev->db_stride)];
264 	nvmeq->dbbuf_sq_ei = &dev->dbbuf_eis[sq_idx(qid, dev->db_stride)];
265 	nvmeq->dbbuf_cq_ei = &dev->dbbuf_eis[cq_idx(qid, dev->db_stride)];
266 }
267 
268 static void nvme_dbbuf_set(struct nvme_dev *dev)
269 {
270 	struct nvme_command c;
271 
272 	if (!dev->dbbuf_dbs)
273 		return;
274 
275 	memset(&c, 0, sizeof(c));
276 	c.dbbuf.opcode = nvme_admin_dbbuf;
277 	c.dbbuf.prp1 = cpu_to_le64(dev->dbbuf_dbs_dma_addr);
278 	c.dbbuf.prp2 = cpu_to_le64(dev->dbbuf_eis_dma_addr);
279 
280 	if (nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0)) {
281 		dev_warn(dev->ctrl.device, "unable to set dbbuf\n");
282 		/* Free memory and continue on */
283 		nvme_dbbuf_dma_free(dev);
284 	}
285 }
286 
287 static inline int nvme_dbbuf_need_event(u16 event_idx, u16 new_idx, u16 old)
288 {
289 	return (u16)(new_idx - event_idx - 1) < (u16)(new_idx - old);
290 }
291 
292 /* Update dbbuf and return true if an MMIO is required */
293 static bool nvme_dbbuf_update_and_check_event(u16 value, u32 *dbbuf_db,
294 					      volatile u32 *dbbuf_ei)
295 {
296 	if (dbbuf_db) {
297 		u16 old_value;
298 
299 		/*
300 		 * Ensure that the queue is written before updating
301 		 * the doorbell in memory
302 		 */
303 		wmb();
304 
305 		old_value = *dbbuf_db;
306 		*dbbuf_db = value;
307 
308 		if (!nvme_dbbuf_need_event(*dbbuf_ei, value, old_value))
309 			return false;
310 	}
311 
312 	return true;
313 }
314 
315 /*
316  * Max size of iod being embedded in the request payload
317  */
318 #define NVME_INT_PAGES		2
319 #define NVME_INT_BYTES(dev)	(NVME_INT_PAGES * (dev)->ctrl.page_size)
320 
321 /*
322  * Will slightly overestimate the number of pages needed.  This is OK
323  * as it only leads to a small amount of wasted memory for the lifetime of
324  * the I/O.
325  */
326 static int nvme_npages(unsigned size, struct nvme_dev *dev)
327 {
328 	unsigned nprps = DIV_ROUND_UP(size + dev->ctrl.page_size,
329 				      dev->ctrl.page_size);
330 	return DIV_ROUND_UP(8 * nprps, PAGE_SIZE - 8);
331 }
332 
333 static unsigned int nvme_iod_alloc_size(struct nvme_dev *dev,
334 		unsigned int size, unsigned int nseg)
335 {
336 	return sizeof(__le64 *) * nvme_npages(size, dev) +
337 			sizeof(struct scatterlist) * nseg;
338 }
339 
340 static unsigned int nvme_cmd_size(struct nvme_dev *dev)
341 {
342 	return sizeof(struct nvme_iod) +
343 		nvme_iod_alloc_size(dev, NVME_INT_BYTES(dev), NVME_INT_PAGES);
344 }
345 
346 static int nvme_admin_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
347 				unsigned int hctx_idx)
348 {
349 	struct nvme_dev *dev = data;
350 	struct nvme_queue *nvmeq = dev->queues[0];
351 
352 	WARN_ON(hctx_idx != 0);
353 	WARN_ON(dev->admin_tagset.tags[0] != hctx->tags);
354 	WARN_ON(nvmeq->tags);
355 
356 	hctx->driver_data = nvmeq;
357 	nvmeq->tags = &dev->admin_tagset.tags[0];
358 	return 0;
359 }
360 
361 static void nvme_admin_exit_hctx(struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx)
362 {
363 	struct nvme_queue *nvmeq = hctx->driver_data;
364 
365 	nvmeq->tags = NULL;
366 }
367 
368 static int nvme_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
369 			  unsigned int hctx_idx)
370 {
371 	struct nvme_dev *dev = data;
372 	struct nvme_queue *nvmeq = dev->queues[hctx_idx + 1];
373 
374 	if (!nvmeq->tags)
375 		nvmeq->tags = &dev->tagset.tags[hctx_idx];
376 
377 	WARN_ON(dev->tagset.tags[hctx_idx] != hctx->tags);
378 	hctx->driver_data = nvmeq;
379 	return 0;
380 }
381 
382 static int nvme_init_request(struct blk_mq_tag_set *set, struct request *req,
383 		unsigned int hctx_idx, unsigned int numa_node)
384 {
385 	struct nvme_dev *dev = set->driver_data;
386 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
387 	int queue_idx = (set == &dev->tagset) ? hctx_idx + 1 : 0;
388 	struct nvme_queue *nvmeq = dev->queues[queue_idx];
389 
390 	BUG_ON(!nvmeq);
391 	iod->nvmeq = nvmeq;
392 	return 0;
393 }
394 
395 static int nvme_pci_map_queues(struct blk_mq_tag_set *set)
396 {
397 	struct nvme_dev *dev = set->driver_data;
398 
399 	return blk_mq_pci_map_queues(set, to_pci_dev(dev->dev));
400 }
401 
402 /**
403  * __nvme_submit_cmd() - Copy a command into a queue and ring the doorbell
404  * @nvmeq: The queue to use
405  * @cmd: The command to send
406  *
407  * Safe to use from interrupt context
408  */
409 static void __nvme_submit_cmd(struct nvme_queue *nvmeq,
410 						struct nvme_command *cmd)
411 {
412 	u16 tail = nvmeq->sq_tail;
413 
414 	if (nvmeq->sq_cmds_io)
415 		memcpy_toio(&nvmeq->sq_cmds_io[tail], cmd, sizeof(*cmd));
416 	else
417 		memcpy(&nvmeq->sq_cmds[tail], cmd, sizeof(*cmd));
418 
419 	if (++tail == nvmeq->q_depth)
420 		tail = 0;
421 	if (nvme_dbbuf_update_and_check_event(tail, nvmeq->dbbuf_sq_db,
422 					      nvmeq->dbbuf_sq_ei))
423 		writel(tail, nvmeq->q_db);
424 	nvmeq->sq_tail = tail;
425 }
426 
427 static __le64 **iod_list(struct request *req)
428 {
429 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
430 	return (__le64 **)(iod->sg + blk_rq_nr_phys_segments(req));
431 }
432 
433 static blk_status_t nvme_init_iod(struct request *rq, struct nvme_dev *dev)
434 {
435 	struct nvme_iod *iod = blk_mq_rq_to_pdu(rq);
436 	int nseg = blk_rq_nr_phys_segments(rq);
437 	unsigned int size = blk_rq_payload_bytes(rq);
438 
439 	if (nseg > NVME_INT_PAGES || size > NVME_INT_BYTES(dev)) {
440 		iod->sg = kmalloc(nvme_iod_alloc_size(dev, size, nseg), GFP_ATOMIC);
441 		if (!iod->sg)
442 			return BLK_STS_RESOURCE;
443 	} else {
444 		iod->sg = iod->inline_sg;
445 	}
446 
447 	iod->aborted = 0;
448 	iod->npages = -1;
449 	iod->nents = 0;
450 	iod->length = size;
451 
452 	return BLK_STS_OK;
453 }
454 
455 static void nvme_free_iod(struct nvme_dev *dev, struct request *req)
456 {
457 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
458 	const int last_prp = dev->ctrl.page_size / 8 - 1;
459 	int i;
460 	__le64 **list = iod_list(req);
461 	dma_addr_t prp_dma = iod->first_dma;
462 
463 	if (iod->npages == 0)
464 		dma_pool_free(dev->prp_small_pool, list[0], prp_dma);
465 	for (i = 0; i < iod->npages; i++) {
466 		__le64 *prp_list = list[i];
467 		dma_addr_t next_prp_dma = le64_to_cpu(prp_list[last_prp]);
468 		dma_pool_free(dev->prp_page_pool, prp_list, prp_dma);
469 		prp_dma = next_prp_dma;
470 	}
471 
472 	if (iod->sg != iod->inline_sg)
473 		kfree(iod->sg);
474 }
475 
476 #ifdef CONFIG_BLK_DEV_INTEGRITY
477 static void nvme_dif_prep(u32 p, u32 v, struct t10_pi_tuple *pi)
478 {
479 	if (be32_to_cpu(pi->ref_tag) == v)
480 		pi->ref_tag = cpu_to_be32(p);
481 }
482 
483 static void nvme_dif_complete(u32 p, u32 v, struct t10_pi_tuple *pi)
484 {
485 	if (be32_to_cpu(pi->ref_tag) == p)
486 		pi->ref_tag = cpu_to_be32(v);
487 }
488 
489 /**
490  * nvme_dif_remap - remaps ref tags to bip seed and physical lba
491  *
492  * The virtual start sector is the one that was originally submitted by the
493  * block layer.	Due to partitioning, MD/DM cloning, etc. the actual physical
494  * start sector may be different. Remap protection information to match the
495  * physical LBA on writes, and back to the original seed on reads.
496  *
497  * Type 0 and 3 do not have a ref tag, so no remapping required.
498  */
499 static void nvme_dif_remap(struct request *req,
500 			void (*dif_swap)(u32 p, u32 v, struct t10_pi_tuple *pi))
501 {
502 	struct nvme_ns *ns = req->rq_disk->private_data;
503 	struct bio_integrity_payload *bip;
504 	struct t10_pi_tuple *pi;
505 	void *p, *pmap;
506 	u32 i, nlb, ts, phys, virt;
507 
508 	if (!ns->pi_type || ns->pi_type == NVME_NS_DPS_PI_TYPE3)
509 		return;
510 
511 	bip = bio_integrity(req->bio);
512 	if (!bip)
513 		return;
514 
515 	pmap = kmap_atomic(bip->bip_vec->bv_page) + bip->bip_vec->bv_offset;
516 
517 	p = pmap;
518 	virt = bip_get_seed(bip);
519 	phys = nvme_block_nr(ns, blk_rq_pos(req));
520 	nlb = (blk_rq_bytes(req) >> ns->lba_shift);
521 	ts = ns->disk->queue->integrity.tuple_size;
522 
523 	for (i = 0; i < nlb; i++, virt++, phys++) {
524 		pi = (struct t10_pi_tuple *)p;
525 		dif_swap(phys, virt, pi);
526 		p += ts;
527 	}
528 	kunmap_atomic(pmap);
529 }
530 #else /* CONFIG_BLK_DEV_INTEGRITY */
531 static void nvme_dif_remap(struct request *req,
532 			void (*dif_swap)(u32 p, u32 v, struct t10_pi_tuple *pi))
533 {
534 }
535 static void nvme_dif_prep(u32 p, u32 v, struct t10_pi_tuple *pi)
536 {
537 }
538 static void nvme_dif_complete(u32 p, u32 v, struct t10_pi_tuple *pi)
539 {
540 }
541 #endif
542 
543 static blk_status_t nvme_setup_prps(struct nvme_dev *dev, struct request *req)
544 {
545 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
546 	struct dma_pool *pool;
547 	int length = blk_rq_payload_bytes(req);
548 	struct scatterlist *sg = iod->sg;
549 	int dma_len = sg_dma_len(sg);
550 	u64 dma_addr = sg_dma_address(sg);
551 	u32 page_size = dev->ctrl.page_size;
552 	int offset = dma_addr & (page_size - 1);
553 	__le64 *prp_list;
554 	__le64 **list = iod_list(req);
555 	dma_addr_t prp_dma;
556 	int nprps, i;
557 
558 	length -= (page_size - offset);
559 	if (length <= 0)
560 		return BLK_STS_OK;
561 
562 	dma_len -= (page_size - offset);
563 	if (dma_len) {
564 		dma_addr += (page_size - offset);
565 	} else {
566 		sg = sg_next(sg);
567 		dma_addr = sg_dma_address(sg);
568 		dma_len = sg_dma_len(sg);
569 	}
570 
571 	if (length <= page_size) {
572 		iod->first_dma = dma_addr;
573 		return BLK_STS_OK;
574 	}
575 
576 	nprps = DIV_ROUND_UP(length, page_size);
577 	if (nprps <= (256 / 8)) {
578 		pool = dev->prp_small_pool;
579 		iod->npages = 0;
580 	} else {
581 		pool = dev->prp_page_pool;
582 		iod->npages = 1;
583 	}
584 
585 	prp_list = dma_pool_alloc(pool, GFP_ATOMIC, &prp_dma);
586 	if (!prp_list) {
587 		iod->first_dma = dma_addr;
588 		iod->npages = -1;
589 		return BLK_STS_RESOURCE;
590 	}
591 	list[0] = prp_list;
592 	iod->first_dma = prp_dma;
593 	i = 0;
594 	for (;;) {
595 		if (i == page_size >> 3) {
596 			__le64 *old_prp_list = prp_list;
597 			prp_list = dma_pool_alloc(pool, GFP_ATOMIC, &prp_dma);
598 			if (!prp_list)
599 				return BLK_STS_RESOURCE;
600 			list[iod->npages++] = prp_list;
601 			prp_list[0] = old_prp_list[i - 1];
602 			old_prp_list[i - 1] = cpu_to_le64(prp_dma);
603 			i = 1;
604 		}
605 		prp_list[i++] = cpu_to_le64(dma_addr);
606 		dma_len -= page_size;
607 		dma_addr += page_size;
608 		length -= page_size;
609 		if (length <= 0)
610 			break;
611 		if (dma_len > 0)
612 			continue;
613 		if (unlikely(dma_len < 0))
614 			goto bad_sgl;
615 		sg = sg_next(sg);
616 		dma_addr = sg_dma_address(sg);
617 		dma_len = sg_dma_len(sg);
618 	}
619 
620 	return BLK_STS_OK;
621 
622  bad_sgl:
623 	if (WARN_ONCE(1, "Invalid SGL for payload:%d nents:%d\n",
624 				blk_rq_payload_bytes(req), iod->nents)) {
625 		for_each_sg(iod->sg, sg, iod->nents, i) {
626 			dma_addr_t phys = sg_phys(sg);
627 			pr_warn("sg[%d] phys_addr:%pad offset:%d length:%d "
628 			       "dma_address:%pad dma_length:%d\n", i, &phys,
629 					sg->offset, sg->length,
630 					&sg_dma_address(sg),
631 					sg_dma_len(sg));
632 		}
633 	}
634 	return BLK_STS_IOERR;
635 
636 }
637 
638 static blk_status_t nvme_map_data(struct nvme_dev *dev, struct request *req,
639 		struct nvme_command *cmnd)
640 {
641 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
642 	struct request_queue *q = req->q;
643 	enum dma_data_direction dma_dir = rq_data_dir(req) ?
644 			DMA_TO_DEVICE : DMA_FROM_DEVICE;
645 	blk_status_t ret = BLK_STS_IOERR;
646 
647 	sg_init_table(iod->sg, blk_rq_nr_phys_segments(req));
648 	iod->nents = blk_rq_map_sg(q, req, iod->sg);
649 	if (!iod->nents)
650 		goto out;
651 
652 	ret = BLK_STS_RESOURCE;
653 	if (!dma_map_sg_attrs(dev->dev, iod->sg, iod->nents, dma_dir,
654 				DMA_ATTR_NO_WARN))
655 		goto out;
656 
657 	ret = nvme_setup_prps(dev, req);
658 	if (ret != BLK_STS_OK)
659 		goto out_unmap;
660 
661 	ret = BLK_STS_IOERR;
662 	if (blk_integrity_rq(req)) {
663 		if (blk_rq_count_integrity_sg(q, req->bio) != 1)
664 			goto out_unmap;
665 
666 		sg_init_table(&iod->meta_sg, 1);
667 		if (blk_rq_map_integrity_sg(q, req->bio, &iod->meta_sg) != 1)
668 			goto out_unmap;
669 
670 		if (rq_data_dir(req))
671 			nvme_dif_remap(req, nvme_dif_prep);
672 
673 		if (!dma_map_sg(dev->dev, &iod->meta_sg, 1, dma_dir))
674 			goto out_unmap;
675 	}
676 
677 	cmnd->rw.dptr.prp1 = cpu_to_le64(sg_dma_address(iod->sg));
678 	cmnd->rw.dptr.prp2 = cpu_to_le64(iod->first_dma);
679 	if (blk_integrity_rq(req))
680 		cmnd->rw.metadata = cpu_to_le64(sg_dma_address(&iod->meta_sg));
681 	return BLK_STS_OK;
682 
683 out_unmap:
684 	dma_unmap_sg(dev->dev, iod->sg, iod->nents, dma_dir);
685 out:
686 	return ret;
687 }
688 
689 static void nvme_unmap_data(struct nvme_dev *dev, struct request *req)
690 {
691 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
692 	enum dma_data_direction dma_dir = rq_data_dir(req) ?
693 			DMA_TO_DEVICE : DMA_FROM_DEVICE;
694 
695 	if (iod->nents) {
696 		dma_unmap_sg(dev->dev, iod->sg, iod->nents, dma_dir);
697 		if (blk_integrity_rq(req)) {
698 			if (!rq_data_dir(req))
699 				nvme_dif_remap(req, nvme_dif_complete);
700 			dma_unmap_sg(dev->dev, &iod->meta_sg, 1, dma_dir);
701 		}
702 	}
703 
704 	nvme_cleanup_cmd(req);
705 	nvme_free_iod(dev, req);
706 }
707 
708 /*
709  * NOTE: ns is NULL when called on the admin queue.
710  */
711 static blk_status_t nvme_queue_rq(struct blk_mq_hw_ctx *hctx,
712 			 const struct blk_mq_queue_data *bd)
713 {
714 	struct nvme_ns *ns = hctx->queue->queuedata;
715 	struct nvme_queue *nvmeq = hctx->driver_data;
716 	struct nvme_dev *dev = nvmeq->dev;
717 	struct request *req = bd->rq;
718 	struct nvme_command cmnd;
719 	blk_status_t ret;
720 
721 	ret = nvme_setup_cmd(ns, req, &cmnd);
722 	if (ret)
723 		return ret;
724 
725 	ret = nvme_init_iod(req, dev);
726 	if (ret)
727 		goto out_free_cmd;
728 
729 	if (blk_rq_nr_phys_segments(req)) {
730 		ret = nvme_map_data(dev, req, &cmnd);
731 		if (ret)
732 			goto out_cleanup_iod;
733 	}
734 
735 	blk_mq_start_request(req);
736 
737 	spin_lock_irq(&nvmeq->q_lock);
738 	if (unlikely(nvmeq->cq_vector < 0)) {
739 		ret = BLK_STS_IOERR;
740 		spin_unlock_irq(&nvmeq->q_lock);
741 		goto out_cleanup_iod;
742 	}
743 	__nvme_submit_cmd(nvmeq, &cmnd);
744 	nvme_process_cq(nvmeq);
745 	spin_unlock_irq(&nvmeq->q_lock);
746 	return BLK_STS_OK;
747 out_cleanup_iod:
748 	nvme_free_iod(dev, req);
749 out_free_cmd:
750 	nvme_cleanup_cmd(req);
751 	return ret;
752 }
753 
754 static void nvme_pci_complete_rq(struct request *req)
755 {
756 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
757 
758 	nvme_unmap_data(iod->nvmeq->dev, req);
759 	nvme_complete_rq(req);
760 }
761 
762 /* We read the CQE phase first to check if the rest of the entry is valid */
763 static inline bool nvme_cqe_valid(struct nvme_queue *nvmeq, u16 head,
764 		u16 phase)
765 {
766 	return (le16_to_cpu(nvmeq->cqes[head].status) & 1) == phase;
767 }
768 
769 static inline void nvme_ring_cq_doorbell(struct nvme_queue *nvmeq)
770 {
771 	u16 head = nvmeq->cq_head;
772 
773 	if (likely(nvmeq->cq_vector >= 0)) {
774 		if (nvme_dbbuf_update_and_check_event(head, nvmeq->dbbuf_cq_db,
775 						      nvmeq->dbbuf_cq_ei))
776 			writel(head, nvmeq->q_db + nvmeq->dev->db_stride);
777 	}
778 }
779 
780 static inline void nvme_handle_cqe(struct nvme_queue *nvmeq,
781 		struct nvme_completion *cqe)
782 {
783 	struct request *req;
784 
785 	if (unlikely(cqe->command_id >= nvmeq->q_depth)) {
786 		dev_warn(nvmeq->dev->ctrl.device,
787 			"invalid id %d completed on queue %d\n",
788 			cqe->command_id, le16_to_cpu(cqe->sq_id));
789 		return;
790 	}
791 
792 	/*
793 	 * AEN requests are special as they don't time out and can
794 	 * survive any kind of queue freeze and often don't respond to
795 	 * aborts.  We don't even bother to allocate a struct request
796 	 * for them but rather special case them here.
797 	 */
798 	if (unlikely(nvmeq->qid == 0 &&
799 			cqe->command_id >= NVME_AQ_BLKMQ_DEPTH)) {
800 		nvme_complete_async_event(&nvmeq->dev->ctrl,
801 				cqe->status, &cqe->result);
802 		return;
803 	}
804 
805 	nvmeq->cqe_seen = 1;
806 	req = blk_mq_tag_to_rq(*nvmeq->tags, cqe->command_id);
807 	nvme_end_request(req, cqe->status, cqe->result);
808 }
809 
810 static inline bool nvme_read_cqe(struct nvme_queue *nvmeq,
811 		struct nvme_completion *cqe)
812 {
813 	if (nvme_cqe_valid(nvmeq, nvmeq->cq_head, nvmeq->cq_phase)) {
814 		*cqe = nvmeq->cqes[nvmeq->cq_head];
815 
816 		if (++nvmeq->cq_head == nvmeq->q_depth) {
817 			nvmeq->cq_head = 0;
818 			nvmeq->cq_phase = !nvmeq->cq_phase;
819 		}
820 		return true;
821 	}
822 	return false;
823 }
824 
825 static void nvme_process_cq(struct nvme_queue *nvmeq)
826 {
827 	struct nvme_completion cqe;
828 	int consumed = 0;
829 
830 	while (nvme_read_cqe(nvmeq, &cqe)) {
831 		nvme_handle_cqe(nvmeq, &cqe);
832 		consumed++;
833 	}
834 
835 	if (consumed)
836 		nvme_ring_cq_doorbell(nvmeq);
837 }
838 
839 static irqreturn_t nvme_irq(int irq, void *data)
840 {
841 	irqreturn_t result;
842 	struct nvme_queue *nvmeq = data;
843 	spin_lock(&nvmeq->q_lock);
844 	nvme_process_cq(nvmeq);
845 	result = nvmeq->cqe_seen ? IRQ_HANDLED : IRQ_NONE;
846 	nvmeq->cqe_seen = 0;
847 	spin_unlock(&nvmeq->q_lock);
848 	return result;
849 }
850 
851 static irqreturn_t nvme_irq_check(int irq, void *data)
852 {
853 	struct nvme_queue *nvmeq = data;
854 	if (nvme_cqe_valid(nvmeq, nvmeq->cq_head, nvmeq->cq_phase))
855 		return IRQ_WAKE_THREAD;
856 	return IRQ_NONE;
857 }
858 
859 static int __nvme_poll(struct nvme_queue *nvmeq, unsigned int tag)
860 {
861 	struct nvme_completion cqe;
862 	int found = 0, consumed = 0;
863 
864 	if (!nvme_cqe_valid(nvmeq, nvmeq->cq_head, nvmeq->cq_phase))
865 		return 0;
866 
867 	spin_lock_irq(&nvmeq->q_lock);
868 	while (nvme_read_cqe(nvmeq, &cqe)) {
869 		nvme_handle_cqe(nvmeq, &cqe);
870 		consumed++;
871 
872 		if (tag == cqe.command_id) {
873 			found = 1;
874 			break;
875 		}
876        }
877 
878 	if (consumed)
879 		nvme_ring_cq_doorbell(nvmeq);
880 	spin_unlock_irq(&nvmeq->q_lock);
881 
882 	return found;
883 }
884 
885 static int nvme_poll(struct blk_mq_hw_ctx *hctx, unsigned int tag)
886 {
887 	struct nvme_queue *nvmeq = hctx->driver_data;
888 
889 	return __nvme_poll(nvmeq, tag);
890 }
891 
892 static void nvme_pci_submit_async_event(struct nvme_ctrl *ctrl, int aer_idx)
893 {
894 	struct nvme_dev *dev = to_nvme_dev(ctrl);
895 	struct nvme_queue *nvmeq = dev->queues[0];
896 	struct nvme_command c;
897 
898 	memset(&c, 0, sizeof(c));
899 	c.common.opcode = nvme_admin_async_event;
900 	c.common.command_id = NVME_AQ_BLKMQ_DEPTH + aer_idx;
901 
902 	spin_lock_irq(&nvmeq->q_lock);
903 	__nvme_submit_cmd(nvmeq, &c);
904 	spin_unlock_irq(&nvmeq->q_lock);
905 }
906 
907 static int adapter_delete_queue(struct nvme_dev *dev, u8 opcode, u16 id)
908 {
909 	struct nvme_command c;
910 
911 	memset(&c, 0, sizeof(c));
912 	c.delete_queue.opcode = opcode;
913 	c.delete_queue.qid = cpu_to_le16(id);
914 
915 	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
916 }
917 
918 static int adapter_alloc_cq(struct nvme_dev *dev, u16 qid,
919 						struct nvme_queue *nvmeq)
920 {
921 	struct nvme_command c;
922 	int flags = NVME_QUEUE_PHYS_CONTIG | NVME_CQ_IRQ_ENABLED;
923 
924 	/*
925 	 * Note: we (ab)use the fact the the prp fields survive if no data
926 	 * is attached to the request.
927 	 */
928 	memset(&c, 0, sizeof(c));
929 	c.create_cq.opcode = nvme_admin_create_cq;
930 	c.create_cq.prp1 = cpu_to_le64(nvmeq->cq_dma_addr);
931 	c.create_cq.cqid = cpu_to_le16(qid);
932 	c.create_cq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
933 	c.create_cq.cq_flags = cpu_to_le16(flags);
934 	c.create_cq.irq_vector = cpu_to_le16(nvmeq->cq_vector);
935 
936 	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
937 }
938 
939 static int adapter_alloc_sq(struct nvme_dev *dev, u16 qid,
940 						struct nvme_queue *nvmeq)
941 {
942 	struct nvme_command c;
943 	int flags = NVME_QUEUE_PHYS_CONTIG;
944 
945 	/*
946 	 * Note: we (ab)use the fact the the prp fields survive if no data
947 	 * is attached to the request.
948 	 */
949 	memset(&c, 0, sizeof(c));
950 	c.create_sq.opcode = nvme_admin_create_sq;
951 	c.create_sq.prp1 = cpu_to_le64(nvmeq->sq_dma_addr);
952 	c.create_sq.sqid = cpu_to_le16(qid);
953 	c.create_sq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
954 	c.create_sq.sq_flags = cpu_to_le16(flags);
955 	c.create_sq.cqid = cpu_to_le16(qid);
956 
957 	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
958 }
959 
960 static int adapter_delete_cq(struct nvme_dev *dev, u16 cqid)
961 {
962 	return adapter_delete_queue(dev, nvme_admin_delete_cq, cqid);
963 }
964 
965 static int adapter_delete_sq(struct nvme_dev *dev, u16 sqid)
966 {
967 	return adapter_delete_queue(dev, nvme_admin_delete_sq, sqid);
968 }
969 
970 static void abort_endio(struct request *req, blk_status_t error)
971 {
972 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
973 	struct nvme_queue *nvmeq = iod->nvmeq;
974 
975 	dev_warn(nvmeq->dev->ctrl.device,
976 		 "Abort status: 0x%x", nvme_req(req)->status);
977 	atomic_inc(&nvmeq->dev->ctrl.abort_limit);
978 	blk_mq_free_request(req);
979 }
980 
981 static bool nvme_should_reset(struct nvme_dev *dev, u32 csts)
982 {
983 
984 	/* If true, indicates loss of adapter communication, possibly by a
985 	 * NVMe Subsystem reset.
986 	 */
987 	bool nssro = dev->subsystem && (csts & NVME_CSTS_NSSRO);
988 
989 	/* If there is a reset ongoing, we shouldn't reset again. */
990 	if (dev->ctrl.state == NVME_CTRL_RESETTING)
991 		return false;
992 
993 	/* We shouldn't reset unless the controller is on fatal error state
994 	 * _or_ if we lost the communication with it.
995 	 */
996 	if (!(csts & NVME_CSTS_CFS) && !nssro)
997 		return false;
998 
999 	/* If PCI error recovery process is happening, we cannot reset or
1000 	 * the recovery mechanism will surely fail.
1001 	 */
1002 	if (pci_channel_offline(to_pci_dev(dev->dev)))
1003 		return false;
1004 
1005 	return true;
1006 }
1007 
1008 static void nvme_warn_reset(struct nvme_dev *dev, u32 csts)
1009 {
1010 	/* Read a config register to help see what died. */
1011 	u16 pci_status;
1012 	int result;
1013 
1014 	result = pci_read_config_word(to_pci_dev(dev->dev), PCI_STATUS,
1015 				      &pci_status);
1016 	if (result == PCIBIOS_SUCCESSFUL)
1017 		dev_warn(dev->ctrl.device,
1018 			 "controller is down; will reset: CSTS=0x%x, PCI_STATUS=0x%hx\n",
1019 			 csts, pci_status);
1020 	else
1021 		dev_warn(dev->ctrl.device,
1022 			 "controller is down; will reset: CSTS=0x%x, PCI_STATUS read failed (%d)\n",
1023 			 csts, result);
1024 }
1025 
1026 static enum blk_eh_timer_return nvme_timeout(struct request *req, bool reserved)
1027 {
1028 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
1029 	struct nvme_queue *nvmeq = iod->nvmeq;
1030 	struct nvme_dev *dev = nvmeq->dev;
1031 	struct request *abort_req;
1032 	struct nvme_command cmd;
1033 	u32 csts = readl(dev->bar + NVME_REG_CSTS);
1034 
1035 	/*
1036 	 * Reset immediately if the controller is failed
1037 	 */
1038 	if (nvme_should_reset(dev, csts)) {
1039 		nvme_warn_reset(dev, csts);
1040 		nvme_dev_disable(dev, false);
1041 		nvme_reset_ctrl(&dev->ctrl);
1042 		return BLK_EH_HANDLED;
1043 	}
1044 
1045 	/*
1046 	 * Did we miss an interrupt?
1047 	 */
1048 	if (__nvme_poll(nvmeq, req->tag)) {
1049 		dev_warn(dev->ctrl.device,
1050 			 "I/O %d QID %d timeout, completion polled\n",
1051 			 req->tag, nvmeq->qid);
1052 		return BLK_EH_HANDLED;
1053 	}
1054 
1055 	/*
1056 	 * Shutdown immediately if controller times out while starting. The
1057 	 * reset work will see the pci device disabled when it gets the forced
1058 	 * cancellation error. All outstanding requests are completed on
1059 	 * shutdown, so we return BLK_EH_HANDLED.
1060 	 */
1061 	if (dev->ctrl.state == NVME_CTRL_RESETTING) {
1062 		dev_warn(dev->ctrl.device,
1063 			 "I/O %d QID %d timeout, disable controller\n",
1064 			 req->tag, nvmeq->qid);
1065 		nvme_dev_disable(dev, false);
1066 		nvme_req(req)->flags |= NVME_REQ_CANCELLED;
1067 		return BLK_EH_HANDLED;
1068 	}
1069 
1070 	/*
1071  	 * Shutdown the controller immediately and schedule a reset if the
1072  	 * command was already aborted once before and still hasn't been
1073  	 * returned to the driver, or if this is the admin queue.
1074 	 */
1075 	if (!nvmeq->qid || iod->aborted) {
1076 		dev_warn(dev->ctrl.device,
1077 			 "I/O %d QID %d timeout, reset controller\n",
1078 			 req->tag, nvmeq->qid);
1079 		nvme_dev_disable(dev, false);
1080 		nvme_reset_ctrl(&dev->ctrl);
1081 
1082 		/*
1083 		 * Mark the request as handled, since the inline shutdown
1084 		 * forces all outstanding requests to complete.
1085 		 */
1086 		nvme_req(req)->flags |= NVME_REQ_CANCELLED;
1087 		return BLK_EH_HANDLED;
1088 	}
1089 
1090 	if (atomic_dec_return(&dev->ctrl.abort_limit) < 0) {
1091 		atomic_inc(&dev->ctrl.abort_limit);
1092 		return BLK_EH_RESET_TIMER;
1093 	}
1094 	iod->aborted = 1;
1095 
1096 	memset(&cmd, 0, sizeof(cmd));
1097 	cmd.abort.opcode = nvme_admin_abort_cmd;
1098 	cmd.abort.cid = req->tag;
1099 	cmd.abort.sqid = cpu_to_le16(nvmeq->qid);
1100 
1101 	dev_warn(nvmeq->dev->ctrl.device,
1102 		"I/O %d QID %d timeout, aborting\n",
1103 		 req->tag, nvmeq->qid);
1104 
1105 	abort_req = nvme_alloc_request(dev->ctrl.admin_q, &cmd,
1106 			BLK_MQ_REQ_NOWAIT, NVME_QID_ANY);
1107 	if (IS_ERR(abort_req)) {
1108 		atomic_inc(&dev->ctrl.abort_limit);
1109 		return BLK_EH_RESET_TIMER;
1110 	}
1111 
1112 	abort_req->timeout = ADMIN_TIMEOUT;
1113 	abort_req->end_io_data = NULL;
1114 	blk_execute_rq_nowait(abort_req->q, NULL, abort_req, 0, abort_endio);
1115 
1116 	/*
1117 	 * The aborted req will be completed on receiving the abort req.
1118 	 * We enable the timer again. If hit twice, it'll cause a device reset,
1119 	 * as the device then is in a faulty state.
1120 	 */
1121 	return BLK_EH_RESET_TIMER;
1122 }
1123 
1124 static void nvme_free_queue(struct nvme_queue *nvmeq)
1125 {
1126 	dma_free_coherent(nvmeq->q_dmadev, CQ_SIZE(nvmeq->q_depth),
1127 				(void *)nvmeq->cqes, nvmeq->cq_dma_addr);
1128 	if (nvmeq->sq_cmds)
1129 		dma_free_coherent(nvmeq->q_dmadev, SQ_SIZE(nvmeq->q_depth),
1130 					nvmeq->sq_cmds, nvmeq->sq_dma_addr);
1131 	kfree(nvmeq);
1132 }
1133 
1134 static void nvme_free_queues(struct nvme_dev *dev, int lowest)
1135 {
1136 	int i;
1137 
1138 	for (i = dev->ctrl.queue_count - 1; i >= lowest; i--) {
1139 		struct nvme_queue *nvmeq = dev->queues[i];
1140 		dev->ctrl.queue_count--;
1141 		dev->queues[i] = NULL;
1142 		nvme_free_queue(nvmeq);
1143 	}
1144 }
1145 
1146 /**
1147  * nvme_suspend_queue - put queue into suspended state
1148  * @nvmeq - queue to suspend
1149  */
1150 static int nvme_suspend_queue(struct nvme_queue *nvmeq)
1151 {
1152 	int vector;
1153 
1154 	spin_lock_irq(&nvmeq->q_lock);
1155 	if (nvmeq->cq_vector == -1) {
1156 		spin_unlock_irq(&nvmeq->q_lock);
1157 		return 1;
1158 	}
1159 	vector = nvmeq->cq_vector;
1160 	nvmeq->dev->online_queues--;
1161 	nvmeq->cq_vector = -1;
1162 	spin_unlock_irq(&nvmeq->q_lock);
1163 
1164 	if (!nvmeq->qid && nvmeq->dev->ctrl.admin_q)
1165 		blk_mq_quiesce_queue(nvmeq->dev->ctrl.admin_q);
1166 
1167 	pci_free_irq(to_pci_dev(nvmeq->dev->dev), vector, nvmeq);
1168 
1169 	return 0;
1170 }
1171 
1172 static void nvme_disable_admin_queue(struct nvme_dev *dev, bool shutdown)
1173 {
1174 	struct nvme_queue *nvmeq = dev->queues[0];
1175 
1176 	if (!nvmeq)
1177 		return;
1178 	if (nvme_suspend_queue(nvmeq))
1179 		return;
1180 
1181 	if (shutdown)
1182 		nvme_shutdown_ctrl(&dev->ctrl);
1183 	else
1184 		nvme_disable_ctrl(&dev->ctrl, dev->ctrl.cap);
1185 
1186 	spin_lock_irq(&nvmeq->q_lock);
1187 	nvme_process_cq(nvmeq);
1188 	spin_unlock_irq(&nvmeq->q_lock);
1189 }
1190 
1191 static int nvme_cmb_qdepth(struct nvme_dev *dev, int nr_io_queues,
1192 				int entry_size)
1193 {
1194 	int q_depth = dev->q_depth;
1195 	unsigned q_size_aligned = roundup(q_depth * entry_size,
1196 					  dev->ctrl.page_size);
1197 
1198 	if (q_size_aligned * nr_io_queues > dev->cmb_size) {
1199 		u64 mem_per_q = div_u64(dev->cmb_size, nr_io_queues);
1200 		mem_per_q = round_down(mem_per_q, dev->ctrl.page_size);
1201 		q_depth = div_u64(mem_per_q, entry_size);
1202 
1203 		/*
1204 		 * Ensure the reduced q_depth is above some threshold where it
1205 		 * would be better to map queues in system memory with the
1206 		 * original depth
1207 		 */
1208 		if (q_depth < 64)
1209 			return -ENOMEM;
1210 	}
1211 
1212 	return q_depth;
1213 }
1214 
1215 static int nvme_alloc_sq_cmds(struct nvme_dev *dev, struct nvme_queue *nvmeq,
1216 				int qid, int depth)
1217 {
1218 	if (qid && dev->cmb && use_cmb_sqes && NVME_CMB_SQS(dev->cmbsz)) {
1219 		unsigned offset = (qid - 1) * roundup(SQ_SIZE(depth),
1220 						      dev->ctrl.page_size);
1221 		nvmeq->sq_dma_addr = dev->cmb_dma_addr + offset;
1222 		nvmeq->sq_cmds_io = dev->cmb + offset;
1223 	} else {
1224 		nvmeq->sq_cmds = dma_alloc_coherent(dev->dev, SQ_SIZE(depth),
1225 					&nvmeq->sq_dma_addr, GFP_KERNEL);
1226 		if (!nvmeq->sq_cmds)
1227 			return -ENOMEM;
1228 	}
1229 
1230 	return 0;
1231 }
1232 
1233 static struct nvme_queue *nvme_alloc_queue(struct nvme_dev *dev, int qid,
1234 							int depth, int node)
1235 {
1236 	struct nvme_queue *nvmeq = kzalloc_node(sizeof(*nvmeq), GFP_KERNEL,
1237 							node);
1238 	if (!nvmeq)
1239 		return NULL;
1240 
1241 	nvmeq->cqes = dma_zalloc_coherent(dev->dev, CQ_SIZE(depth),
1242 					  &nvmeq->cq_dma_addr, GFP_KERNEL);
1243 	if (!nvmeq->cqes)
1244 		goto free_nvmeq;
1245 
1246 	if (nvme_alloc_sq_cmds(dev, nvmeq, qid, depth))
1247 		goto free_cqdma;
1248 
1249 	nvmeq->q_dmadev = dev->dev;
1250 	nvmeq->dev = dev;
1251 	spin_lock_init(&nvmeq->q_lock);
1252 	nvmeq->cq_head = 0;
1253 	nvmeq->cq_phase = 1;
1254 	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
1255 	nvmeq->q_depth = depth;
1256 	nvmeq->qid = qid;
1257 	nvmeq->cq_vector = -1;
1258 	dev->queues[qid] = nvmeq;
1259 	dev->ctrl.queue_count++;
1260 
1261 	return nvmeq;
1262 
1263  free_cqdma:
1264 	dma_free_coherent(dev->dev, CQ_SIZE(depth), (void *)nvmeq->cqes,
1265 							nvmeq->cq_dma_addr);
1266  free_nvmeq:
1267 	kfree(nvmeq);
1268 	return NULL;
1269 }
1270 
1271 static int queue_request_irq(struct nvme_queue *nvmeq)
1272 {
1273 	struct pci_dev *pdev = to_pci_dev(nvmeq->dev->dev);
1274 	int nr = nvmeq->dev->ctrl.instance;
1275 
1276 	if (use_threaded_interrupts) {
1277 		return pci_request_irq(pdev, nvmeq->cq_vector, nvme_irq_check,
1278 				nvme_irq, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
1279 	} else {
1280 		return pci_request_irq(pdev, nvmeq->cq_vector, nvme_irq,
1281 				NULL, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
1282 	}
1283 }
1284 
1285 static void nvme_init_queue(struct nvme_queue *nvmeq, u16 qid)
1286 {
1287 	struct nvme_dev *dev = nvmeq->dev;
1288 
1289 	spin_lock_irq(&nvmeq->q_lock);
1290 	nvmeq->sq_tail = 0;
1291 	nvmeq->cq_head = 0;
1292 	nvmeq->cq_phase = 1;
1293 	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
1294 	memset((void *)nvmeq->cqes, 0, CQ_SIZE(nvmeq->q_depth));
1295 	nvme_dbbuf_init(dev, nvmeq, qid);
1296 	dev->online_queues++;
1297 	spin_unlock_irq(&nvmeq->q_lock);
1298 }
1299 
1300 static int nvme_create_queue(struct nvme_queue *nvmeq, int qid)
1301 {
1302 	struct nvme_dev *dev = nvmeq->dev;
1303 	int result;
1304 
1305 	nvmeq->cq_vector = qid - 1;
1306 	result = adapter_alloc_cq(dev, qid, nvmeq);
1307 	if (result < 0)
1308 		return result;
1309 
1310 	result = adapter_alloc_sq(dev, qid, nvmeq);
1311 	if (result < 0)
1312 		goto release_cq;
1313 
1314 	result = queue_request_irq(nvmeq);
1315 	if (result < 0)
1316 		goto release_sq;
1317 
1318 	nvme_init_queue(nvmeq, qid);
1319 	return result;
1320 
1321  release_sq:
1322 	adapter_delete_sq(dev, qid);
1323  release_cq:
1324 	adapter_delete_cq(dev, qid);
1325 	return result;
1326 }
1327 
1328 static const struct blk_mq_ops nvme_mq_admin_ops = {
1329 	.queue_rq	= nvme_queue_rq,
1330 	.complete	= nvme_pci_complete_rq,
1331 	.init_hctx	= nvme_admin_init_hctx,
1332 	.exit_hctx      = nvme_admin_exit_hctx,
1333 	.init_request	= nvme_init_request,
1334 	.timeout	= nvme_timeout,
1335 };
1336 
1337 static const struct blk_mq_ops nvme_mq_ops = {
1338 	.queue_rq	= nvme_queue_rq,
1339 	.complete	= nvme_pci_complete_rq,
1340 	.init_hctx	= nvme_init_hctx,
1341 	.init_request	= nvme_init_request,
1342 	.map_queues	= nvme_pci_map_queues,
1343 	.timeout	= nvme_timeout,
1344 	.poll		= nvme_poll,
1345 };
1346 
1347 static void nvme_dev_remove_admin(struct nvme_dev *dev)
1348 {
1349 	if (dev->ctrl.admin_q && !blk_queue_dying(dev->ctrl.admin_q)) {
1350 		/*
1351 		 * If the controller was reset during removal, it's possible
1352 		 * user requests may be waiting on a stopped queue. Start the
1353 		 * queue to flush these to completion.
1354 		 */
1355 		blk_mq_unquiesce_queue(dev->ctrl.admin_q);
1356 		blk_cleanup_queue(dev->ctrl.admin_q);
1357 		blk_mq_free_tag_set(&dev->admin_tagset);
1358 	}
1359 }
1360 
1361 static int nvme_alloc_admin_tags(struct nvme_dev *dev)
1362 {
1363 	if (!dev->ctrl.admin_q) {
1364 		dev->admin_tagset.ops = &nvme_mq_admin_ops;
1365 		dev->admin_tagset.nr_hw_queues = 1;
1366 
1367 		/*
1368 		 * Subtract one to leave an empty queue entry for 'Full Queue'
1369 		 * condition. See NVM-Express 1.2 specification, section 4.1.2.
1370 		 */
1371 		dev->admin_tagset.queue_depth = NVME_AQ_BLKMQ_DEPTH - 1;
1372 		dev->admin_tagset.timeout = ADMIN_TIMEOUT;
1373 		dev->admin_tagset.numa_node = dev_to_node(dev->dev);
1374 		dev->admin_tagset.cmd_size = nvme_cmd_size(dev);
1375 		dev->admin_tagset.flags = BLK_MQ_F_NO_SCHED;
1376 		dev->admin_tagset.driver_data = dev;
1377 
1378 		if (blk_mq_alloc_tag_set(&dev->admin_tagset))
1379 			return -ENOMEM;
1380 
1381 		dev->ctrl.admin_q = blk_mq_init_queue(&dev->admin_tagset);
1382 		if (IS_ERR(dev->ctrl.admin_q)) {
1383 			blk_mq_free_tag_set(&dev->admin_tagset);
1384 			return -ENOMEM;
1385 		}
1386 		if (!blk_get_queue(dev->ctrl.admin_q)) {
1387 			nvme_dev_remove_admin(dev);
1388 			dev->ctrl.admin_q = NULL;
1389 			return -ENODEV;
1390 		}
1391 	} else
1392 		blk_mq_unquiesce_queue(dev->ctrl.admin_q);
1393 
1394 	return 0;
1395 }
1396 
1397 static unsigned long db_bar_size(struct nvme_dev *dev, unsigned nr_io_queues)
1398 {
1399 	return NVME_REG_DBS + ((nr_io_queues + 1) * 8 * dev->db_stride);
1400 }
1401 
1402 static int nvme_remap_bar(struct nvme_dev *dev, unsigned long size)
1403 {
1404 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1405 
1406 	if (size <= dev->bar_mapped_size)
1407 		return 0;
1408 	if (size > pci_resource_len(pdev, 0))
1409 		return -ENOMEM;
1410 	if (dev->bar)
1411 		iounmap(dev->bar);
1412 	dev->bar = ioremap(pci_resource_start(pdev, 0), size);
1413 	if (!dev->bar) {
1414 		dev->bar_mapped_size = 0;
1415 		return -ENOMEM;
1416 	}
1417 	dev->bar_mapped_size = size;
1418 	dev->dbs = dev->bar + NVME_REG_DBS;
1419 
1420 	return 0;
1421 }
1422 
1423 static int nvme_pci_configure_admin_queue(struct nvme_dev *dev)
1424 {
1425 	int result;
1426 	u32 aqa;
1427 	struct nvme_queue *nvmeq;
1428 
1429 	result = nvme_remap_bar(dev, db_bar_size(dev, 0));
1430 	if (result < 0)
1431 		return result;
1432 
1433 	dev->subsystem = readl(dev->bar + NVME_REG_VS) >= NVME_VS(1, 1, 0) ?
1434 				NVME_CAP_NSSRC(dev->ctrl.cap) : 0;
1435 
1436 	if (dev->subsystem &&
1437 	    (readl(dev->bar + NVME_REG_CSTS) & NVME_CSTS_NSSRO))
1438 		writel(NVME_CSTS_NSSRO, dev->bar + NVME_REG_CSTS);
1439 
1440 	result = nvme_disable_ctrl(&dev->ctrl, dev->ctrl.cap);
1441 	if (result < 0)
1442 		return result;
1443 
1444 	nvmeq = dev->queues[0];
1445 	if (!nvmeq) {
1446 		nvmeq = nvme_alloc_queue(dev, 0, NVME_AQ_DEPTH,
1447 					dev_to_node(dev->dev));
1448 		if (!nvmeq)
1449 			return -ENOMEM;
1450 	}
1451 
1452 	aqa = nvmeq->q_depth - 1;
1453 	aqa |= aqa << 16;
1454 
1455 	writel(aqa, dev->bar + NVME_REG_AQA);
1456 	lo_hi_writeq(nvmeq->sq_dma_addr, dev->bar + NVME_REG_ASQ);
1457 	lo_hi_writeq(nvmeq->cq_dma_addr, dev->bar + NVME_REG_ACQ);
1458 
1459 	result = nvme_enable_ctrl(&dev->ctrl, dev->ctrl.cap);
1460 	if (result)
1461 		return result;
1462 
1463 	nvmeq->cq_vector = 0;
1464 	result = queue_request_irq(nvmeq);
1465 	if (result) {
1466 		nvmeq->cq_vector = -1;
1467 		return result;
1468 	}
1469 
1470 	return result;
1471 }
1472 
1473 static int nvme_create_io_queues(struct nvme_dev *dev)
1474 {
1475 	unsigned i, max;
1476 	int ret = 0;
1477 
1478 	for (i = dev->ctrl.queue_count; i <= dev->max_qid; i++) {
1479 		/* vector == qid - 1, match nvme_create_queue */
1480 		if (!nvme_alloc_queue(dev, i, dev->q_depth,
1481 		     pci_irq_get_node(to_pci_dev(dev->dev), i - 1))) {
1482 			ret = -ENOMEM;
1483 			break;
1484 		}
1485 	}
1486 
1487 	max = min(dev->max_qid, dev->ctrl.queue_count - 1);
1488 	for (i = dev->online_queues; i <= max; i++) {
1489 		ret = nvme_create_queue(dev->queues[i], i);
1490 		if (ret)
1491 			break;
1492 	}
1493 
1494 	/*
1495 	 * Ignore failing Create SQ/CQ commands, we can continue with less
1496 	 * than the desired aount of queues, and even a controller without
1497 	 * I/O queues an still be used to issue admin commands.  This might
1498 	 * be useful to upgrade a buggy firmware for example.
1499 	 */
1500 	return ret >= 0 ? 0 : ret;
1501 }
1502 
1503 static ssize_t nvme_cmb_show(struct device *dev,
1504 			     struct device_attribute *attr,
1505 			     char *buf)
1506 {
1507 	struct nvme_dev *ndev = to_nvme_dev(dev_get_drvdata(dev));
1508 
1509 	return scnprintf(buf, PAGE_SIZE, "cmbloc : x%08x\ncmbsz  : x%08x\n",
1510 		       ndev->cmbloc, ndev->cmbsz);
1511 }
1512 static DEVICE_ATTR(cmb, S_IRUGO, nvme_cmb_show, NULL);
1513 
1514 static void __iomem *nvme_map_cmb(struct nvme_dev *dev)
1515 {
1516 	u64 szu, size, offset;
1517 	resource_size_t bar_size;
1518 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1519 	void __iomem *cmb;
1520 	dma_addr_t dma_addr;
1521 
1522 	dev->cmbsz = readl(dev->bar + NVME_REG_CMBSZ);
1523 	if (!(NVME_CMB_SZ(dev->cmbsz)))
1524 		return NULL;
1525 	dev->cmbloc = readl(dev->bar + NVME_REG_CMBLOC);
1526 
1527 	if (!use_cmb_sqes)
1528 		return NULL;
1529 
1530 	szu = (u64)1 << (12 + 4 * NVME_CMB_SZU(dev->cmbsz));
1531 	size = szu * NVME_CMB_SZ(dev->cmbsz);
1532 	offset = szu * NVME_CMB_OFST(dev->cmbloc);
1533 	bar_size = pci_resource_len(pdev, NVME_CMB_BIR(dev->cmbloc));
1534 
1535 	if (offset > bar_size)
1536 		return NULL;
1537 
1538 	/*
1539 	 * Controllers may support a CMB size larger than their BAR,
1540 	 * for example, due to being behind a bridge. Reduce the CMB to
1541 	 * the reported size of the BAR
1542 	 */
1543 	if (size > bar_size - offset)
1544 		size = bar_size - offset;
1545 
1546 	dma_addr = pci_resource_start(pdev, NVME_CMB_BIR(dev->cmbloc)) + offset;
1547 	cmb = ioremap_wc(dma_addr, size);
1548 	if (!cmb)
1549 		return NULL;
1550 
1551 	dev->cmb_dma_addr = dma_addr;
1552 	dev->cmb_size = size;
1553 	return cmb;
1554 }
1555 
1556 static inline void nvme_release_cmb(struct nvme_dev *dev)
1557 {
1558 	if (dev->cmb) {
1559 		iounmap(dev->cmb);
1560 		dev->cmb = NULL;
1561 		sysfs_remove_file_from_group(&dev->ctrl.device->kobj,
1562 					     &dev_attr_cmb.attr, NULL);
1563 		dev->cmbsz = 0;
1564 	}
1565 }
1566 
1567 static int nvme_set_host_mem(struct nvme_dev *dev, u32 bits)
1568 {
1569 	u64 dma_addr = dev->host_mem_descs_dma;
1570 	struct nvme_command c;
1571 	int ret;
1572 
1573 	memset(&c, 0, sizeof(c));
1574 	c.features.opcode	= nvme_admin_set_features;
1575 	c.features.fid		= cpu_to_le32(NVME_FEAT_HOST_MEM_BUF);
1576 	c.features.dword11	= cpu_to_le32(bits);
1577 	c.features.dword12	= cpu_to_le32(dev->host_mem_size >>
1578 					      ilog2(dev->ctrl.page_size));
1579 	c.features.dword13	= cpu_to_le32(lower_32_bits(dma_addr));
1580 	c.features.dword14	= cpu_to_le32(upper_32_bits(dma_addr));
1581 	c.features.dword15	= cpu_to_le32(dev->nr_host_mem_descs);
1582 
1583 	ret = nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1584 	if (ret) {
1585 		dev_warn(dev->ctrl.device,
1586 			 "failed to set host mem (err %d, flags %#x).\n",
1587 			 ret, bits);
1588 	}
1589 	return ret;
1590 }
1591 
1592 static void nvme_free_host_mem(struct nvme_dev *dev)
1593 {
1594 	int i;
1595 
1596 	for (i = 0; i < dev->nr_host_mem_descs; i++) {
1597 		struct nvme_host_mem_buf_desc *desc = &dev->host_mem_descs[i];
1598 		size_t size = le32_to_cpu(desc->size) * dev->ctrl.page_size;
1599 
1600 		dma_free_coherent(dev->dev, size, dev->host_mem_desc_bufs[i],
1601 				le64_to_cpu(desc->addr));
1602 	}
1603 
1604 	kfree(dev->host_mem_desc_bufs);
1605 	dev->host_mem_desc_bufs = NULL;
1606 	dma_free_coherent(dev->dev,
1607 			dev->nr_host_mem_descs * sizeof(*dev->host_mem_descs),
1608 			dev->host_mem_descs, dev->host_mem_descs_dma);
1609 	dev->host_mem_descs = NULL;
1610 }
1611 
1612 static int nvme_alloc_host_mem(struct nvme_dev *dev, u64 min, u64 preferred)
1613 {
1614 	struct nvme_host_mem_buf_desc *descs;
1615 	u32 chunk_size, max_entries, len;
1616 	dma_addr_t descs_dma;
1617 	int i = 0;
1618 	void **bufs;
1619 	u64 size = 0, tmp;
1620 
1621 	/* start big and work our way down */
1622 	chunk_size = min(preferred, (u64)PAGE_SIZE << MAX_ORDER);
1623 retry:
1624 	tmp = (preferred + chunk_size - 1);
1625 	do_div(tmp, chunk_size);
1626 	max_entries = tmp;
1627 	descs = dma_zalloc_coherent(dev->dev, max_entries * sizeof(*descs),
1628 			&descs_dma, GFP_KERNEL);
1629 	if (!descs)
1630 		goto out;
1631 
1632 	bufs = kcalloc(max_entries, sizeof(*bufs), GFP_KERNEL);
1633 	if (!bufs)
1634 		goto out_free_descs;
1635 
1636 	for (size = 0; size < preferred; size += len) {
1637 		dma_addr_t dma_addr;
1638 
1639 		len = min_t(u64, chunk_size, preferred - size);
1640 		bufs[i] = dma_alloc_attrs(dev->dev, len, &dma_addr, GFP_KERNEL,
1641 				DMA_ATTR_NO_KERNEL_MAPPING | DMA_ATTR_NO_WARN);
1642 		if (!bufs[i])
1643 			break;
1644 
1645 		descs[i].addr = cpu_to_le64(dma_addr);
1646 		descs[i].size = cpu_to_le32(len / dev->ctrl.page_size);
1647 		i++;
1648 	}
1649 
1650 	if (!size || (min && size < min)) {
1651 		dev_warn(dev->ctrl.device,
1652 			"failed to allocate host memory buffer.\n");
1653 		goto out_free_bufs;
1654 	}
1655 
1656 	dev_info(dev->ctrl.device,
1657 		"allocated %lld MiB host memory buffer.\n",
1658 		size >> ilog2(SZ_1M));
1659 	dev->nr_host_mem_descs = i;
1660 	dev->host_mem_size = size;
1661 	dev->host_mem_descs = descs;
1662 	dev->host_mem_descs_dma = descs_dma;
1663 	dev->host_mem_desc_bufs = bufs;
1664 	return 0;
1665 
1666 out_free_bufs:
1667 	while (--i >= 0) {
1668 		size_t size = le32_to_cpu(descs[i].size) * dev->ctrl.page_size;
1669 
1670 		dma_free_coherent(dev->dev, size, bufs[i],
1671 				le64_to_cpu(descs[i].addr));
1672 	}
1673 
1674 	kfree(bufs);
1675 out_free_descs:
1676 	dma_free_coherent(dev->dev, max_entries * sizeof(*descs), descs,
1677 			descs_dma);
1678 out:
1679 	/* try a smaller chunk size if we failed early */
1680 	if (chunk_size >= PAGE_SIZE * 2 && (i == 0 || size < min)) {
1681 		chunk_size /= 2;
1682 		goto retry;
1683 	}
1684 	dev->host_mem_descs = NULL;
1685 	return -ENOMEM;
1686 }
1687 
1688 static void nvme_setup_host_mem(struct nvme_dev *dev)
1689 {
1690 	u64 max = (u64)max_host_mem_size_mb * SZ_1M;
1691 	u64 preferred = (u64)dev->ctrl.hmpre * 4096;
1692 	u64 min = (u64)dev->ctrl.hmmin * 4096;
1693 	u32 enable_bits = NVME_HOST_MEM_ENABLE;
1694 
1695 	preferred = min(preferred, max);
1696 	if (min > max) {
1697 		dev_warn(dev->ctrl.device,
1698 			"min host memory (%lld MiB) above limit (%d MiB).\n",
1699 			min >> ilog2(SZ_1M), max_host_mem_size_mb);
1700 		nvme_free_host_mem(dev);
1701 		return;
1702 	}
1703 
1704 	/*
1705 	 * If we already have a buffer allocated check if we can reuse it.
1706 	 */
1707 	if (dev->host_mem_descs) {
1708 		if (dev->host_mem_size >= min)
1709 			enable_bits |= NVME_HOST_MEM_RETURN;
1710 		else
1711 			nvme_free_host_mem(dev);
1712 	}
1713 
1714 	if (!dev->host_mem_descs) {
1715 		if (nvme_alloc_host_mem(dev, min, preferred))
1716 			return;
1717 	}
1718 
1719 	if (nvme_set_host_mem(dev, enable_bits))
1720 		nvme_free_host_mem(dev);
1721 }
1722 
1723 static int nvme_setup_io_queues(struct nvme_dev *dev)
1724 {
1725 	struct nvme_queue *adminq = dev->queues[0];
1726 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1727 	int result, nr_io_queues;
1728 	unsigned long size;
1729 
1730 	nr_io_queues = num_present_cpus();
1731 	result = nvme_set_queue_count(&dev->ctrl, &nr_io_queues);
1732 	if (result < 0)
1733 		return result;
1734 
1735 	if (nr_io_queues == 0)
1736 		return 0;
1737 
1738 	if (dev->cmb && NVME_CMB_SQS(dev->cmbsz)) {
1739 		result = nvme_cmb_qdepth(dev, nr_io_queues,
1740 				sizeof(struct nvme_command));
1741 		if (result > 0)
1742 			dev->q_depth = result;
1743 		else
1744 			nvme_release_cmb(dev);
1745 	}
1746 
1747 	do {
1748 		size = db_bar_size(dev, nr_io_queues);
1749 		result = nvme_remap_bar(dev, size);
1750 		if (!result)
1751 			break;
1752 		if (!--nr_io_queues)
1753 			return -ENOMEM;
1754 	} while (1);
1755 	adminq->q_db = dev->dbs;
1756 
1757 	/* Deregister the admin queue's interrupt */
1758 	pci_free_irq(pdev, 0, adminq);
1759 
1760 	/*
1761 	 * If we enable msix early due to not intx, disable it again before
1762 	 * setting up the full range we need.
1763 	 */
1764 	pci_free_irq_vectors(pdev);
1765 	nr_io_queues = pci_alloc_irq_vectors(pdev, 1, nr_io_queues,
1766 			PCI_IRQ_ALL_TYPES | PCI_IRQ_AFFINITY);
1767 	if (nr_io_queues <= 0)
1768 		return -EIO;
1769 	dev->max_qid = nr_io_queues;
1770 
1771 	/*
1772 	 * Should investigate if there's a performance win from allocating
1773 	 * more queues than interrupt vectors; it might allow the submission
1774 	 * path to scale better, even if the receive path is limited by the
1775 	 * number of interrupts.
1776 	 */
1777 
1778 	result = queue_request_irq(adminq);
1779 	if (result) {
1780 		adminq->cq_vector = -1;
1781 		return result;
1782 	}
1783 	return nvme_create_io_queues(dev);
1784 }
1785 
1786 static void nvme_del_queue_end(struct request *req, blk_status_t error)
1787 {
1788 	struct nvme_queue *nvmeq = req->end_io_data;
1789 
1790 	blk_mq_free_request(req);
1791 	complete(&nvmeq->dev->ioq_wait);
1792 }
1793 
1794 static void nvme_del_cq_end(struct request *req, blk_status_t error)
1795 {
1796 	struct nvme_queue *nvmeq = req->end_io_data;
1797 
1798 	if (!error) {
1799 		unsigned long flags;
1800 
1801 		/*
1802 		 * We might be called with the AQ q_lock held
1803 		 * and the I/O queue q_lock should always
1804 		 * nest inside the AQ one.
1805 		 */
1806 		spin_lock_irqsave_nested(&nvmeq->q_lock, flags,
1807 					SINGLE_DEPTH_NESTING);
1808 		nvme_process_cq(nvmeq);
1809 		spin_unlock_irqrestore(&nvmeq->q_lock, flags);
1810 	}
1811 
1812 	nvme_del_queue_end(req, error);
1813 }
1814 
1815 static int nvme_delete_queue(struct nvme_queue *nvmeq, u8 opcode)
1816 {
1817 	struct request_queue *q = nvmeq->dev->ctrl.admin_q;
1818 	struct request *req;
1819 	struct nvme_command cmd;
1820 
1821 	memset(&cmd, 0, sizeof(cmd));
1822 	cmd.delete_queue.opcode = opcode;
1823 	cmd.delete_queue.qid = cpu_to_le16(nvmeq->qid);
1824 
1825 	req = nvme_alloc_request(q, &cmd, BLK_MQ_REQ_NOWAIT, NVME_QID_ANY);
1826 	if (IS_ERR(req))
1827 		return PTR_ERR(req);
1828 
1829 	req->timeout = ADMIN_TIMEOUT;
1830 	req->end_io_data = nvmeq;
1831 
1832 	blk_execute_rq_nowait(q, NULL, req, false,
1833 			opcode == nvme_admin_delete_cq ?
1834 				nvme_del_cq_end : nvme_del_queue_end);
1835 	return 0;
1836 }
1837 
1838 static void nvme_disable_io_queues(struct nvme_dev *dev, int queues)
1839 {
1840 	int pass;
1841 	unsigned long timeout;
1842 	u8 opcode = nvme_admin_delete_sq;
1843 
1844 	for (pass = 0; pass < 2; pass++) {
1845 		int sent = 0, i = queues;
1846 
1847 		reinit_completion(&dev->ioq_wait);
1848  retry:
1849 		timeout = ADMIN_TIMEOUT;
1850 		for (; i > 0; i--, sent++)
1851 			if (nvme_delete_queue(dev->queues[i], opcode))
1852 				break;
1853 
1854 		while (sent--) {
1855 			timeout = wait_for_completion_io_timeout(&dev->ioq_wait, timeout);
1856 			if (timeout == 0)
1857 				return;
1858 			if (i)
1859 				goto retry;
1860 		}
1861 		opcode = nvme_admin_delete_cq;
1862 	}
1863 }
1864 
1865 /*
1866  * Return: error value if an error occurred setting up the queues or calling
1867  * Identify Device.  0 if these succeeded, even if adding some of the
1868  * namespaces failed.  At the moment, these failures are silent.  TBD which
1869  * failures should be reported.
1870  */
1871 static int nvme_dev_add(struct nvme_dev *dev)
1872 {
1873 	if (!dev->ctrl.tagset) {
1874 		dev->tagset.ops = &nvme_mq_ops;
1875 		dev->tagset.nr_hw_queues = dev->online_queues - 1;
1876 		dev->tagset.timeout = NVME_IO_TIMEOUT;
1877 		dev->tagset.numa_node = dev_to_node(dev->dev);
1878 		dev->tagset.queue_depth =
1879 				min_t(int, dev->q_depth, BLK_MQ_MAX_DEPTH) - 1;
1880 		dev->tagset.cmd_size = nvme_cmd_size(dev);
1881 		dev->tagset.flags = BLK_MQ_F_SHOULD_MERGE;
1882 		dev->tagset.driver_data = dev;
1883 
1884 		if (blk_mq_alloc_tag_set(&dev->tagset))
1885 			return 0;
1886 		dev->ctrl.tagset = &dev->tagset;
1887 
1888 		nvme_dbbuf_set(dev);
1889 	} else {
1890 		blk_mq_update_nr_hw_queues(&dev->tagset, dev->online_queues - 1);
1891 
1892 		/* Free previously allocated queues that are no longer usable */
1893 		nvme_free_queues(dev, dev->online_queues);
1894 	}
1895 
1896 	return 0;
1897 }
1898 
1899 static int nvme_pci_enable(struct nvme_dev *dev)
1900 {
1901 	int result = -ENOMEM;
1902 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1903 
1904 	if (pci_enable_device_mem(pdev))
1905 		return result;
1906 
1907 	pci_set_master(pdev);
1908 
1909 	if (dma_set_mask_and_coherent(dev->dev, DMA_BIT_MASK(64)) &&
1910 	    dma_set_mask_and_coherent(dev->dev, DMA_BIT_MASK(32)))
1911 		goto disable;
1912 
1913 	if (readl(dev->bar + NVME_REG_CSTS) == -1) {
1914 		result = -ENODEV;
1915 		goto disable;
1916 	}
1917 
1918 	/*
1919 	 * Some devices and/or platforms don't advertise or work with INTx
1920 	 * interrupts. Pre-enable a single MSIX or MSI vec for setup. We'll
1921 	 * adjust this later.
1922 	 */
1923 	result = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
1924 	if (result < 0)
1925 		return result;
1926 
1927 	dev->ctrl.cap = lo_hi_readq(dev->bar + NVME_REG_CAP);
1928 
1929 	dev->q_depth = min_t(int, NVME_CAP_MQES(dev->ctrl.cap) + 1,
1930 				io_queue_depth);
1931 	dev->db_stride = 1 << NVME_CAP_STRIDE(dev->ctrl.cap);
1932 	dev->dbs = dev->bar + 4096;
1933 
1934 	/*
1935 	 * Temporary fix for the Apple controller found in the MacBook8,1 and
1936 	 * some MacBook7,1 to avoid controller resets and data loss.
1937 	 */
1938 	if (pdev->vendor == PCI_VENDOR_ID_APPLE && pdev->device == 0x2001) {
1939 		dev->q_depth = 2;
1940 		dev_warn(dev->ctrl.device, "detected Apple NVMe controller, "
1941 			"set queue depth=%u to work around controller resets\n",
1942 			dev->q_depth);
1943 	} else if (pdev->vendor == PCI_VENDOR_ID_SAMSUNG &&
1944 		   (pdev->device == 0xa821 || pdev->device == 0xa822) &&
1945 		   NVME_CAP_MQES(dev->ctrl.cap) == 0) {
1946 		dev->q_depth = 64;
1947 		dev_err(dev->ctrl.device, "detected PM1725 NVMe controller, "
1948                         "set queue depth=%u\n", dev->q_depth);
1949 	}
1950 
1951 	/*
1952 	 * CMBs can currently only exist on >=1.2 PCIe devices. We only
1953 	 * populate sysfs if a CMB is implemented. Since nvme_dev_attrs_group
1954 	 * has no name we can pass NULL as final argument to
1955 	 * sysfs_add_file_to_group.
1956 	 */
1957 
1958 	if (readl(dev->bar + NVME_REG_VS) >= NVME_VS(1, 2, 0)) {
1959 		dev->cmb = nvme_map_cmb(dev);
1960 		if (dev->cmb) {
1961 			if (sysfs_add_file_to_group(&dev->ctrl.device->kobj,
1962 						    &dev_attr_cmb.attr, NULL))
1963 				dev_warn(dev->ctrl.device,
1964 					 "failed to add sysfs attribute for CMB\n");
1965 		}
1966 	}
1967 
1968 	pci_enable_pcie_error_reporting(pdev);
1969 	pci_save_state(pdev);
1970 	return 0;
1971 
1972  disable:
1973 	pci_disable_device(pdev);
1974 	return result;
1975 }
1976 
1977 static void nvme_dev_unmap(struct nvme_dev *dev)
1978 {
1979 	if (dev->bar)
1980 		iounmap(dev->bar);
1981 	pci_release_mem_regions(to_pci_dev(dev->dev));
1982 }
1983 
1984 static void nvme_pci_disable(struct nvme_dev *dev)
1985 {
1986 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1987 
1988 	nvme_release_cmb(dev);
1989 	pci_free_irq_vectors(pdev);
1990 
1991 	if (pci_is_enabled(pdev)) {
1992 		pci_disable_pcie_error_reporting(pdev);
1993 		pci_disable_device(pdev);
1994 	}
1995 }
1996 
1997 static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown)
1998 {
1999 	int i, queues;
2000 	bool dead = true;
2001 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2002 
2003 	mutex_lock(&dev->shutdown_lock);
2004 	if (pci_is_enabled(pdev)) {
2005 		u32 csts = readl(dev->bar + NVME_REG_CSTS);
2006 
2007 		if (dev->ctrl.state == NVME_CTRL_LIVE ||
2008 		    dev->ctrl.state == NVME_CTRL_RESETTING)
2009 			nvme_start_freeze(&dev->ctrl);
2010 		dead = !!((csts & NVME_CSTS_CFS) || !(csts & NVME_CSTS_RDY) ||
2011 			pdev->error_state  != pci_channel_io_normal);
2012 	}
2013 
2014 	/*
2015 	 * Give the controller a chance to complete all entered requests if
2016 	 * doing a safe shutdown.
2017 	 */
2018 	if (!dead) {
2019 		if (shutdown)
2020 			nvme_wait_freeze_timeout(&dev->ctrl, NVME_IO_TIMEOUT);
2021 
2022 		/*
2023 		 * If the controller is still alive tell it to stop using the
2024 		 * host memory buffer.  In theory the shutdown / reset should
2025 		 * make sure that it doesn't access the host memoery anymore,
2026 		 * but I'd rather be safe than sorry..
2027 		 */
2028 		if (dev->host_mem_descs)
2029 			nvme_set_host_mem(dev, 0);
2030 
2031 	}
2032 	nvme_stop_queues(&dev->ctrl);
2033 
2034 	queues = dev->online_queues - 1;
2035 	for (i = dev->ctrl.queue_count - 1; i > 0; i--)
2036 		nvme_suspend_queue(dev->queues[i]);
2037 
2038 	if (dead) {
2039 		/* A device might become IO incapable very soon during
2040 		 * probe, before the admin queue is configured. Thus,
2041 		 * queue_count can be 0 here.
2042 		 */
2043 		if (dev->ctrl.queue_count)
2044 			nvme_suspend_queue(dev->queues[0]);
2045 	} else {
2046 		nvme_disable_io_queues(dev, queues);
2047 		nvme_disable_admin_queue(dev, shutdown);
2048 	}
2049 	nvme_pci_disable(dev);
2050 
2051 	blk_mq_tagset_busy_iter(&dev->tagset, nvme_cancel_request, &dev->ctrl);
2052 	blk_mq_tagset_busy_iter(&dev->admin_tagset, nvme_cancel_request, &dev->ctrl);
2053 
2054 	/*
2055 	 * The driver will not be starting up queues again if shutting down so
2056 	 * must flush all entered requests to their failed completion to avoid
2057 	 * deadlocking blk-mq hot-cpu notifier.
2058 	 */
2059 	if (shutdown)
2060 		nvme_start_queues(&dev->ctrl);
2061 	mutex_unlock(&dev->shutdown_lock);
2062 }
2063 
2064 static int nvme_setup_prp_pools(struct nvme_dev *dev)
2065 {
2066 	dev->prp_page_pool = dma_pool_create("prp list page", dev->dev,
2067 						PAGE_SIZE, PAGE_SIZE, 0);
2068 	if (!dev->prp_page_pool)
2069 		return -ENOMEM;
2070 
2071 	/* Optimisation for I/Os between 4k and 128k */
2072 	dev->prp_small_pool = dma_pool_create("prp list 256", dev->dev,
2073 						256, 256, 0);
2074 	if (!dev->prp_small_pool) {
2075 		dma_pool_destroy(dev->prp_page_pool);
2076 		return -ENOMEM;
2077 	}
2078 	return 0;
2079 }
2080 
2081 static void nvme_release_prp_pools(struct nvme_dev *dev)
2082 {
2083 	dma_pool_destroy(dev->prp_page_pool);
2084 	dma_pool_destroy(dev->prp_small_pool);
2085 }
2086 
2087 static void nvme_pci_free_ctrl(struct nvme_ctrl *ctrl)
2088 {
2089 	struct nvme_dev *dev = to_nvme_dev(ctrl);
2090 
2091 	nvme_dbbuf_dma_free(dev);
2092 	put_device(dev->dev);
2093 	if (dev->tagset.tags)
2094 		blk_mq_free_tag_set(&dev->tagset);
2095 	if (dev->ctrl.admin_q)
2096 		blk_put_queue(dev->ctrl.admin_q);
2097 	kfree(dev->queues);
2098 	free_opal_dev(dev->ctrl.opal_dev);
2099 	kfree(dev);
2100 }
2101 
2102 static void nvme_remove_dead_ctrl(struct nvme_dev *dev, int status)
2103 {
2104 	dev_warn(dev->ctrl.device, "Removing after probe failure status: %d\n", status);
2105 
2106 	kref_get(&dev->ctrl.kref);
2107 	nvme_dev_disable(dev, false);
2108 	if (!schedule_work(&dev->remove_work))
2109 		nvme_put_ctrl(&dev->ctrl);
2110 }
2111 
2112 static void nvme_reset_work(struct work_struct *work)
2113 {
2114 	struct nvme_dev *dev =
2115 		container_of(work, struct nvme_dev, ctrl.reset_work);
2116 	bool was_suspend = !!(dev->ctrl.ctrl_config & NVME_CC_SHN_NORMAL);
2117 	int result = -ENODEV;
2118 
2119 	if (WARN_ON(dev->ctrl.state != NVME_CTRL_RESETTING))
2120 		goto out;
2121 
2122 	/*
2123 	 * If we're called to reset a live controller first shut it down before
2124 	 * moving on.
2125 	 */
2126 	if (dev->ctrl.ctrl_config & NVME_CC_ENABLE)
2127 		nvme_dev_disable(dev, false);
2128 
2129 	result = nvme_pci_enable(dev);
2130 	if (result)
2131 		goto out;
2132 
2133 	result = nvme_pci_configure_admin_queue(dev);
2134 	if (result)
2135 		goto out;
2136 
2137 	nvme_init_queue(dev->queues[0], 0);
2138 	result = nvme_alloc_admin_tags(dev);
2139 	if (result)
2140 		goto out;
2141 
2142 	result = nvme_init_identify(&dev->ctrl);
2143 	if (result)
2144 		goto out;
2145 
2146 	if (dev->ctrl.oacs & NVME_CTRL_OACS_SEC_SUPP) {
2147 		if (!dev->ctrl.opal_dev)
2148 			dev->ctrl.opal_dev =
2149 				init_opal_dev(&dev->ctrl, &nvme_sec_submit);
2150 		else if (was_suspend)
2151 			opal_unlock_from_suspend(dev->ctrl.opal_dev);
2152 	} else {
2153 		free_opal_dev(dev->ctrl.opal_dev);
2154 		dev->ctrl.opal_dev = NULL;
2155 	}
2156 
2157 	if (dev->ctrl.oacs & NVME_CTRL_OACS_DBBUF_SUPP) {
2158 		result = nvme_dbbuf_dma_alloc(dev);
2159 		if (result)
2160 			dev_warn(dev->dev,
2161 				 "unable to allocate dma for dbbuf\n");
2162 	}
2163 
2164 	if (dev->ctrl.hmpre)
2165 		nvme_setup_host_mem(dev);
2166 
2167 	result = nvme_setup_io_queues(dev);
2168 	if (result)
2169 		goto out;
2170 
2171 	/*
2172 	 * Keep the controller around but remove all namespaces if we don't have
2173 	 * any working I/O queue.
2174 	 */
2175 	if (dev->online_queues < 2) {
2176 		dev_warn(dev->ctrl.device, "IO queues not created\n");
2177 		nvme_kill_queues(&dev->ctrl);
2178 		nvme_remove_namespaces(&dev->ctrl);
2179 	} else {
2180 		nvme_start_queues(&dev->ctrl);
2181 		nvme_wait_freeze(&dev->ctrl);
2182 		nvme_dev_add(dev);
2183 		nvme_unfreeze(&dev->ctrl);
2184 	}
2185 
2186 	if (!nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_LIVE)) {
2187 		dev_warn(dev->ctrl.device, "failed to mark controller live\n");
2188 		goto out;
2189 	}
2190 
2191 	nvme_start_ctrl(&dev->ctrl);
2192 	return;
2193 
2194  out:
2195 	nvme_remove_dead_ctrl(dev, result);
2196 }
2197 
2198 static void nvme_remove_dead_ctrl_work(struct work_struct *work)
2199 {
2200 	struct nvme_dev *dev = container_of(work, struct nvme_dev, remove_work);
2201 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2202 
2203 	nvme_kill_queues(&dev->ctrl);
2204 	if (pci_get_drvdata(pdev))
2205 		device_release_driver(&pdev->dev);
2206 	nvme_put_ctrl(&dev->ctrl);
2207 }
2208 
2209 static int nvme_pci_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val)
2210 {
2211 	*val = readl(to_nvme_dev(ctrl)->bar + off);
2212 	return 0;
2213 }
2214 
2215 static int nvme_pci_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val)
2216 {
2217 	writel(val, to_nvme_dev(ctrl)->bar + off);
2218 	return 0;
2219 }
2220 
2221 static int nvme_pci_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val)
2222 {
2223 	*val = readq(to_nvme_dev(ctrl)->bar + off);
2224 	return 0;
2225 }
2226 
2227 static const struct nvme_ctrl_ops nvme_pci_ctrl_ops = {
2228 	.name			= "pcie",
2229 	.module			= THIS_MODULE,
2230 	.flags			= NVME_F_METADATA_SUPPORTED,
2231 	.reg_read32		= nvme_pci_reg_read32,
2232 	.reg_write32		= nvme_pci_reg_write32,
2233 	.reg_read64		= nvme_pci_reg_read64,
2234 	.free_ctrl		= nvme_pci_free_ctrl,
2235 	.submit_async_event	= nvme_pci_submit_async_event,
2236 };
2237 
2238 static int nvme_dev_map(struct nvme_dev *dev)
2239 {
2240 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2241 
2242 	if (pci_request_mem_regions(pdev, "nvme"))
2243 		return -ENODEV;
2244 
2245 	if (nvme_remap_bar(dev, NVME_REG_DBS + 4096))
2246 		goto release;
2247 
2248 	return 0;
2249   release:
2250 	pci_release_mem_regions(pdev);
2251 	return -ENODEV;
2252 }
2253 
2254 static unsigned long check_dell_samsung_bug(struct pci_dev *pdev)
2255 {
2256 	if (pdev->vendor == 0x144d && pdev->device == 0xa802) {
2257 		/*
2258 		 * Several Samsung devices seem to drop off the PCIe bus
2259 		 * randomly when APST is on and uses the deepest sleep state.
2260 		 * This has been observed on a Samsung "SM951 NVMe SAMSUNG
2261 		 * 256GB", a "PM951 NVMe SAMSUNG 512GB", and a "Samsung SSD
2262 		 * 950 PRO 256GB", but it seems to be restricted to two Dell
2263 		 * laptops.
2264 		 */
2265 		if (dmi_match(DMI_SYS_VENDOR, "Dell Inc.") &&
2266 		    (dmi_match(DMI_PRODUCT_NAME, "XPS 15 9550") ||
2267 		     dmi_match(DMI_PRODUCT_NAME, "Precision 5510")))
2268 			return NVME_QUIRK_NO_DEEPEST_PS;
2269 	}
2270 
2271 	return 0;
2272 }
2273 
2274 static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
2275 {
2276 	int node, result = -ENOMEM;
2277 	struct nvme_dev *dev;
2278 	unsigned long quirks = id->driver_data;
2279 
2280 	node = dev_to_node(&pdev->dev);
2281 	if (node == NUMA_NO_NODE)
2282 		set_dev_node(&pdev->dev, first_memory_node);
2283 
2284 	dev = kzalloc_node(sizeof(*dev), GFP_KERNEL, node);
2285 	if (!dev)
2286 		return -ENOMEM;
2287 	dev->queues = kzalloc_node((num_possible_cpus() + 1) * sizeof(void *),
2288 							GFP_KERNEL, node);
2289 	if (!dev->queues)
2290 		goto free;
2291 
2292 	dev->dev = get_device(&pdev->dev);
2293 	pci_set_drvdata(pdev, dev);
2294 
2295 	result = nvme_dev_map(dev);
2296 	if (result)
2297 		goto put_pci;
2298 
2299 	INIT_WORK(&dev->ctrl.reset_work, nvme_reset_work);
2300 	INIT_WORK(&dev->remove_work, nvme_remove_dead_ctrl_work);
2301 	mutex_init(&dev->shutdown_lock);
2302 	init_completion(&dev->ioq_wait);
2303 
2304 	result = nvme_setup_prp_pools(dev);
2305 	if (result)
2306 		goto unmap;
2307 
2308 	quirks |= check_dell_samsung_bug(pdev);
2309 
2310 	result = nvme_init_ctrl(&dev->ctrl, &pdev->dev, &nvme_pci_ctrl_ops,
2311 			quirks);
2312 	if (result)
2313 		goto release_pools;
2314 
2315 	nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_RESETTING);
2316 	dev_info(dev->ctrl.device, "pci function %s\n", dev_name(&pdev->dev));
2317 
2318 	queue_work(nvme_wq, &dev->ctrl.reset_work);
2319 	return 0;
2320 
2321  release_pools:
2322 	nvme_release_prp_pools(dev);
2323  unmap:
2324 	nvme_dev_unmap(dev);
2325  put_pci:
2326 	put_device(dev->dev);
2327  free:
2328 	kfree(dev->queues);
2329 	kfree(dev);
2330 	return result;
2331 }
2332 
2333 static void nvme_reset_prepare(struct pci_dev *pdev)
2334 {
2335 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2336 	nvme_dev_disable(dev, false);
2337 }
2338 
2339 static void nvme_reset_done(struct pci_dev *pdev)
2340 {
2341 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2342 	nvme_reset_ctrl(&dev->ctrl);
2343 }
2344 
2345 static void nvme_shutdown(struct pci_dev *pdev)
2346 {
2347 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2348 	nvme_dev_disable(dev, true);
2349 }
2350 
2351 /*
2352  * The driver's remove may be called on a device in a partially initialized
2353  * state. This function must not have any dependencies on the device state in
2354  * order to proceed.
2355  */
2356 static void nvme_remove(struct pci_dev *pdev)
2357 {
2358 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2359 
2360 	nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DELETING);
2361 
2362 	cancel_work_sync(&dev->ctrl.reset_work);
2363 	pci_set_drvdata(pdev, NULL);
2364 
2365 	if (!pci_device_is_present(pdev)) {
2366 		nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DEAD);
2367 		nvme_dev_disable(dev, false);
2368 	}
2369 
2370 	flush_work(&dev->ctrl.reset_work);
2371 	nvme_stop_ctrl(&dev->ctrl);
2372 	nvme_remove_namespaces(&dev->ctrl);
2373 	nvme_dev_disable(dev, true);
2374 	nvme_free_host_mem(dev);
2375 	nvme_dev_remove_admin(dev);
2376 	nvme_free_queues(dev, 0);
2377 	nvme_uninit_ctrl(&dev->ctrl);
2378 	nvme_release_prp_pools(dev);
2379 	nvme_dev_unmap(dev);
2380 	nvme_put_ctrl(&dev->ctrl);
2381 }
2382 
2383 static int nvme_pci_sriov_configure(struct pci_dev *pdev, int numvfs)
2384 {
2385 	int ret = 0;
2386 
2387 	if (numvfs == 0) {
2388 		if (pci_vfs_assigned(pdev)) {
2389 			dev_warn(&pdev->dev,
2390 				"Cannot disable SR-IOV VFs while assigned\n");
2391 			return -EPERM;
2392 		}
2393 		pci_disable_sriov(pdev);
2394 		return 0;
2395 	}
2396 
2397 	ret = pci_enable_sriov(pdev, numvfs);
2398 	return ret ? ret : numvfs;
2399 }
2400 
2401 #ifdef CONFIG_PM_SLEEP
2402 static int nvme_suspend(struct device *dev)
2403 {
2404 	struct pci_dev *pdev = to_pci_dev(dev);
2405 	struct nvme_dev *ndev = pci_get_drvdata(pdev);
2406 
2407 	nvme_dev_disable(ndev, true);
2408 	return 0;
2409 }
2410 
2411 static int nvme_resume(struct device *dev)
2412 {
2413 	struct pci_dev *pdev = to_pci_dev(dev);
2414 	struct nvme_dev *ndev = pci_get_drvdata(pdev);
2415 
2416 	nvme_reset_ctrl(&ndev->ctrl);
2417 	return 0;
2418 }
2419 #endif
2420 
2421 static SIMPLE_DEV_PM_OPS(nvme_dev_pm_ops, nvme_suspend, nvme_resume);
2422 
2423 static pci_ers_result_t nvme_error_detected(struct pci_dev *pdev,
2424 						pci_channel_state_t state)
2425 {
2426 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2427 
2428 	/*
2429 	 * A frozen channel requires a reset. When detected, this method will
2430 	 * shutdown the controller to quiesce. The controller will be restarted
2431 	 * after the slot reset through driver's slot_reset callback.
2432 	 */
2433 	switch (state) {
2434 	case pci_channel_io_normal:
2435 		return PCI_ERS_RESULT_CAN_RECOVER;
2436 	case pci_channel_io_frozen:
2437 		dev_warn(dev->ctrl.device,
2438 			"frozen state error detected, reset controller\n");
2439 		nvme_dev_disable(dev, false);
2440 		return PCI_ERS_RESULT_NEED_RESET;
2441 	case pci_channel_io_perm_failure:
2442 		dev_warn(dev->ctrl.device,
2443 			"failure state error detected, request disconnect\n");
2444 		return PCI_ERS_RESULT_DISCONNECT;
2445 	}
2446 	return PCI_ERS_RESULT_NEED_RESET;
2447 }
2448 
2449 static pci_ers_result_t nvme_slot_reset(struct pci_dev *pdev)
2450 {
2451 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2452 
2453 	dev_info(dev->ctrl.device, "restart after slot reset\n");
2454 	pci_restore_state(pdev);
2455 	nvme_reset_ctrl(&dev->ctrl);
2456 	return PCI_ERS_RESULT_RECOVERED;
2457 }
2458 
2459 static void nvme_error_resume(struct pci_dev *pdev)
2460 {
2461 	pci_cleanup_aer_uncorrect_error_status(pdev);
2462 }
2463 
2464 static const struct pci_error_handlers nvme_err_handler = {
2465 	.error_detected	= nvme_error_detected,
2466 	.slot_reset	= nvme_slot_reset,
2467 	.resume		= nvme_error_resume,
2468 	.reset_prepare	= nvme_reset_prepare,
2469 	.reset_done	= nvme_reset_done,
2470 };
2471 
2472 static const struct pci_device_id nvme_id_table[] = {
2473 	{ PCI_VDEVICE(INTEL, 0x0953),
2474 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
2475 				NVME_QUIRK_DEALLOCATE_ZEROES, },
2476 	{ PCI_VDEVICE(INTEL, 0x0a53),
2477 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
2478 				NVME_QUIRK_DEALLOCATE_ZEROES, },
2479 	{ PCI_VDEVICE(INTEL, 0x0a54),
2480 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
2481 				NVME_QUIRK_DEALLOCATE_ZEROES, },
2482 	{ PCI_VDEVICE(INTEL, 0x0a55),
2483 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
2484 				NVME_QUIRK_DEALLOCATE_ZEROES, },
2485 	{ PCI_VDEVICE(INTEL, 0xf1a5),	/* Intel 600P/P3100 */
2486 		.driver_data = NVME_QUIRK_NO_DEEPEST_PS },
2487 	{ PCI_VDEVICE(INTEL, 0x5845),	/* Qemu emulated controller */
2488 		.driver_data = NVME_QUIRK_IDENTIFY_CNS, },
2489 	{ PCI_DEVICE(0x1c58, 0x0003),	/* HGST adapter */
2490 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2491 	{ PCI_DEVICE(0x1c5f, 0x0540),	/* Memblaze Pblaze4 adapter */
2492 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2493 	{ PCI_DEVICE(0x144d, 0xa821),   /* Samsung PM1725 */
2494 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2495 	{ PCI_DEVICE(0x144d, 0xa822),   /* Samsung PM1725a */
2496 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2497 	{ PCI_DEVICE_CLASS(PCI_CLASS_STORAGE_EXPRESS, 0xffffff) },
2498 	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2001) },
2499 	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2003) },
2500 	{ 0, }
2501 };
2502 MODULE_DEVICE_TABLE(pci, nvme_id_table);
2503 
2504 static struct pci_driver nvme_driver = {
2505 	.name		= "nvme",
2506 	.id_table	= nvme_id_table,
2507 	.probe		= nvme_probe,
2508 	.remove		= nvme_remove,
2509 	.shutdown	= nvme_shutdown,
2510 	.driver		= {
2511 		.pm	= &nvme_dev_pm_ops,
2512 	},
2513 	.sriov_configure = nvme_pci_sriov_configure,
2514 	.err_handler	= &nvme_err_handler,
2515 };
2516 
2517 static int __init nvme_init(void)
2518 {
2519 	return pci_register_driver(&nvme_driver);
2520 }
2521 
2522 static void __exit nvme_exit(void)
2523 {
2524 	pci_unregister_driver(&nvme_driver);
2525 	_nvme_check_size();
2526 }
2527 
2528 MODULE_AUTHOR("Matthew Wilcox <willy@linux.intel.com>");
2529 MODULE_LICENSE("GPL");
2530 MODULE_VERSION("1.0");
2531 module_init(nvme_init);
2532 module_exit(nvme_exit);
2533