xref: /linux/drivers/nvme/host/pci.c (revision 39f75da7bcc829ddc4d40bb60d0e95520de7898b)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * NVM Express device driver
4  * Copyright (c) 2011-2014, Intel Corporation.
5  */
6 
7 #include <linux/acpi.h>
8 #include <linux/aer.h>
9 #include <linux/async.h>
10 #include <linux/blkdev.h>
11 #include <linux/blk-mq.h>
12 #include <linux/blk-mq-pci.h>
13 #include <linux/dmi.h>
14 #include <linux/init.h>
15 #include <linux/interrupt.h>
16 #include <linux/io.h>
17 #include <linux/mm.h>
18 #include <linux/module.h>
19 #include <linux/mutex.h>
20 #include <linux/once.h>
21 #include <linux/pci.h>
22 #include <linux/suspend.h>
23 #include <linux/t10-pi.h>
24 #include <linux/types.h>
25 #include <linux/io-64-nonatomic-lo-hi.h>
26 #include <linux/io-64-nonatomic-hi-lo.h>
27 #include <linux/sed-opal.h>
28 #include <linux/pci-p2pdma.h>
29 
30 #include "trace.h"
31 #include "nvme.h"
32 
33 #define SQ_SIZE(q)	((q)->q_depth << (q)->sqes)
34 #define CQ_SIZE(q)	((q)->q_depth * sizeof(struct nvme_completion))
35 
36 #define SGES_PER_PAGE	(PAGE_SIZE / sizeof(struct nvme_sgl_desc))
37 
38 /*
39  * These can be higher, but we need to ensure that any command doesn't
40  * require an sg allocation that needs more than a page of data.
41  */
42 #define NVME_MAX_KB_SZ	4096
43 #define NVME_MAX_SEGS	127
44 
45 static int use_threaded_interrupts;
46 module_param(use_threaded_interrupts, int, 0);
47 
48 static bool use_cmb_sqes = true;
49 module_param(use_cmb_sqes, bool, 0444);
50 MODULE_PARM_DESC(use_cmb_sqes, "use controller's memory buffer for I/O SQes");
51 
52 static unsigned int max_host_mem_size_mb = 128;
53 module_param(max_host_mem_size_mb, uint, 0444);
54 MODULE_PARM_DESC(max_host_mem_size_mb,
55 	"Maximum Host Memory Buffer (HMB) size per controller (in MiB)");
56 
57 static unsigned int sgl_threshold = SZ_32K;
58 module_param(sgl_threshold, uint, 0644);
59 MODULE_PARM_DESC(sgl_threshold,
60 		"Use SGLs when average request segment size is larger or equal to "
61 		"this size. Use 0 to disable SGLs.");
62 
63 static int io_queue_depth_set(const char *val, const struct kernel_param *kp);
64 static const struct kernel_param_ops io_queue_depth_ops = {
65 	.set = io_queue_depth_set,
66 	.get = param_get_uint,
67 };
68 
69 static unsigned int io_queue_depth = 1024;
70 module_param_cb(io_queue_depth, &io_queue_depth_ops, &io_queue_depth, 0644);
71 MODULE_PARM_DESC(io_queue_depth, "set io queue depth, should >= 2");
72 
73 static int io_queue_count_set(const char *val, const struct kernel_param *kp)
74 {
75 	unsigned int n;
76 	int ret;
77 
78 	ret = kstrtouint(val, 10, &n);
79 	if (ret != 0 || n > num_possible_cpus())
80 		return -EINVAL;
81 	return param_set_uint(val, kp);
82 }
83 
84 static const struct kernel_param_ops io_queue_count_ops = {
85 	.set = io_queue_count_set,
86 	.get = param_get_uint,
87 };
88 
89 static unsigned int write_queues;
90 module_param_cb(write_queues, &io_queue_count_ops, &write_queues, 0644);
91 MODULE_PARM_DESC(write_queues,
92 	"Number of queues to use for writes. If not set, reads and writes "
93 	"will share a queue set.");
94 
95 static unsigned int poll_queues;
96 module_param_cb(poll_queues, &io_queue_count_ops, &poll_queues, 0644);
97 MODULE_PARM_DESC(poll_queues, "Number of queues to use for polled IO.");
98 
99 static bool noacpi;
100 module_param(noacpi, bool, 0444);
101 MODULE_PARM_DESC(noacpi, "disable acpi bios quirks");
102 
103 struct nvme_dev;
104 struct nvme_queue;
105 
106 static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown);
107 static bool __nvme_disable_io_queues(struct nvme_dev *dev, u8 opcode);
108 
109 /*
110  * Represents an NVM Express device.  Each nvme_dev is a PCI function.
111  */
112 struct nvme_dev {
113 	struct nvme_queue *queues;
114 	struct blk_mq_tag_set tagset;
115 	struct blk_mq_tag_set admin_tagset;
116 	u32 __iomem *dbs;
117 	struct device *dev;
118 	struct dma_pool *prp_page_pool;
119 	struct dma_pool *prp_small_pool;
120 	unsigned online_queues;
121 	unsigned max_qid;
122 	unsigned io_queues[HCTX_MAX_TYPES];
123 	unsigned int num_vecs;
124 	u32 q_depth;
125 	int io_sqes;
126 	u32 db_stride;
127 	void __iomem *bar;
128 	unsigned long bar_mapped_size;
129 	struct work_struct remove_work;
130 	struct mutex shutdown_lock;
131 	bool subsystem;
132 	u64 cmb_size;
133 	bool cmb_use_sqes;
134 	u32 cmbsz;
135 	u32 cmbloc;
136 	struct nvme_ctrl ctrl;
137 	u32 last_ps;
138 
139 	mempool_t *iod_mempool;
140 
141 	/* shadow doorbell buffer support: */
142 	u32 *dbbuf_dbs;
143 	dma_addr_t dbbuf_dbs_dma_addr;
144 	u32 *dbbuf_eis;
145 	dma_addr_t dbbuf_eis_dma_addr;
146 
147 	/* host memory buffer support: */
148 	u64 host_mem_size;
149 	u32 nr_host_mem_descs;
150 	dma_addr_t host_mem_descs_dma;
151 	struct nvme_host_mem_buf_desc *host_mem_descs;
152 	void **host_mem_desc_bufs;
153 	unsigned int nr_allocated_queues;
154 	unsigned int nr_write_queues;
155 	unsigned int nr_poll_queues;
156 };
157 
158 static int io_queue_depth_set(const char *val, const struct kernel_param *kp)
159 {
160 	int ret;
161 	u32 n;
162 
163 	ret = kstrtou32(val, 10, &n);
164 	if (ret != 0 || n < 2)
165 		return -EINVAL;
166 
167 	return param_set_uint(val, kp);
168 }
169 
170 static inline unsigned int sq_idx(unsigned int qid, u32 stride)
171 {
172 	return qid * 2 * stride;
173 }
174 
175 static inline unsigned int cq_idx(unsigned int qid, u32 stride)
176 {
177 	return (qid * 2 + 1) * stride;
178 }
179 
180 static inline struct nvme_dev *to_nvme_dev(struct nvme_ctrl *ctrl)
181 {
182 	return container_of(ctrl, struct nvme_dev, ctrl);
183 }
184 
185 /*
186  * An NVM Express queue.  Each device has at least two (one for admin
187  * commands and one for I/O commands).
188  */
189 struct nvme_queue {
190 	struct nvme_dev *dev;
191 	spinlock_t sq_lock;
192 	void *sq_cmds;
193 	 /* only used for poll queues: */
194 	spinlock_t cq_poll_lock ____cacheline_aligned_in_smp;
195 	struct nvme_completion *cqes;
196 	dma_addr_t sq_dma_addr;
197 	dma_addr_t cq_dma_addr;
198 	u32 __iomem *q_db;
199 	u32 q_depth;
200 	u16 cq_vector;
201 	u16 sq_tail;
202 	u16 last_sq_tail;
203 	u16 cq_head;
204 	u16 qid;
205 	u8 cq_phase;
206 	u8 sqes;
207 	unsigned long flags;
208 #define NVMEQ_ENABLED		0
209 #define NVMEQ_SQ_CMB		1
210 #define NVMEQ_DELETE_ERROR	2
211 #define NVMEQ_POLLED		3
212 	u32 *dbbuf_sq_db;
213 	u32 *dbbuf_cq_db;
214 	u32 *dbbuf_sq_ei;
215 	u32 *dbbuf_cq_ei;
216 	struct completion delete_done;
217 };
218 
219 /*
220  * The nvme_iod describes the data in an I/O.
221  *
222  * The sg pointer contains the list of PRP/SGL chunk allocations in addition
223  * to the actual struct scatterlist.
224  */
225 struct nvme_iod {
226 	struct nvme_request req;
227 	struct nvme_command cmd;
228 	struct nvme_queue *nvmeq;
229 	bool use_sgl;
230 	int aborted;
231 	int npages;		/* In the PRP list. 0 means small pool in use */
232 	int nents;		/* Used in scatterlist */
233 	dma_addr_t first_dma;
234 	unsigned int dma_len;	/* length of single DMA segment mapping */
235 	dma_addr_t meta_dma;
236 	struct scatterlist *sg;
237 };
238 
239 static inline unsigned int nvme_dbbuf_size(struct nvme_dev *dev)
240 {
241 	return dev->nr_allocated_queues * 8 * dev->db_stride;
242 }
243 
244 static int nvme_dbbuf_dma_alloc(struct nvme_dev *dev)
245 {
246 	unsigned int mem_size = nvme_dbbuf_size(dev);
247 
248 	if (dev->dbbuf_dbs)
249 		return 0;
250 
251 	dev->dbbuf_dbs = dma_alloc_coherent(dev->dev, mem_size,
252 					    &dev->dbbuf_dbs_dma_addr,
253 					    GFP_KERNEL);
254 	if (!dev->dbbuf_dbs)
255 		return -ENOMEM;
256 	dev->dbbuf_eis = dma_alloc_coherent(dev->dev, mem_size,
257 					    &dev->dbbuf_eis_dma_addr,
258 					    GFP_KERNEL);
259 	if (!dev->dbbuf_eis) {
260 		dma_free_coherent(dev->dev, mem_size,
261 				  dev->dbbuf_dbs, dev->dbbuf_dbs_dma_addr);
262 		dev->dbbuf_dbs = NULL;
263 		return -ENOMEM;
264 	}
265 
266 	return 0;
267 }
268 
269 static void nvme_dbbuf_dma_free(struct nvme_dev *dev)
270 {
271 	unsigned int mem_size = nvme_dbbuf_size(dev);
272 
273 	if (dev->dbbuf_dbs) {
274 		dma_free_coherent(dev->dev, mem_size,
275 				  dev->dbbuf_dbs, dev->dbbuf_dbs_dma_addr);
276 		dev->dbbuf_dbs = NULL;
277 	}
278 	if (dev->dbbuf_eis) {
279 		dma_free_coherent(dev->dev, mem_size,
280 				  dev->dbbuf_eis, dev->dbbuf_eis_dma_addr);
281 		dev->dbbuf_eis = NULL;
282 	}
283 }
284 
285 static void nvme_dbbuf_init(struct nvme_dev *dev,
286 			    struct nvme_queue *nvmeq, int qid)
287 {
288 	if (!dev->dbbuf_dbs || !qid)
289 		return;
290 
291 	nvmeq->dbbuf_sq_db = &dev->dbbuf_dbs[sq_idx(qid, dev->db_stride)];
292 	nvmeq->dbbuf_cq_db = &dev->dbbuf_dbs[cq_idx(qid, dev->db_stride)];
293 	nvmeq->dbbuf_sq_ei = &dev->dbbuf_eis[sq_idx(qid, dev->db_stride)];
294 	nvmeq->dbbuf_cq_ei = &dev->dbbuf_eis[cq_idx(qid, dev->db_stride)];
295 }
296 
297 static void nvme_dbbuf_free(struct nvme_queue *nvmeq)
298 {
299 	if (!nvmeq->qid)
300 		return;
301 
302 	nvmeq->dbbuf_sq_db = NULL;
303 	nvmeq->dbbuf_cq_db = NULL;
304 	nvmeq->dbbuf_sq_ei = NULL;
305 	nvmeq->dbbuf_cq_ei = NULL;
306 }
307 
308 static void nvme_dbbuf_set(struct nvme_dev *dev)
309 {
310 	struct nvme_command c = { };
311 	unsigned int i;
312 
313 	if (!dev->dbbuf_dbs)
314 		return;
315 
316 	c.dbbuf.opcode = nvme_admin_dbbuf;
317 	c.dbbuf.prp1 = cpu_to_le64(dev->dbbuf_dbs_dma_addr);
318 	c.dbbuf.prp2 = cpu_to_le64(dev->dbbuf_eis_dma_addr);
319 
320 	if (nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0)) {
321 		dev_warn(dev->ctrl.device, "unable to set dbbuf\n");
322 		/* Free memory and continue on */
323 		nvme_dbbuf_dma_free(dev);
324 
325 		for (i = 1; i <= dev->online_queues; i++)
326 			nvme_dbbuf_free(&dev->queues[i]);
327 	}
328 }
329 
330 static inline int nvme_dbbuf_need_event(u16 event_idx, u16 new_idx, u16 old)
331 {
332 	return (u16)(new_idx - event_idx - 1) < (u16)(new_idx - old);
333 }
334 
335 /* Update dbbuf and return true if an MMIO is required */
336 static bool nvme_dbbuf_update_and_check_event(u16 value, u32 *dbbuf_db,
337 					      volatile u32 *dbbuf_ei)
338 {
339 	if (dbbuf_db) {
340 		u16 old_value;
341 
342 		/*
343 		 * Ensure that the queue is written before updating
344 		 * the doorbell in memory
345 		 */
346 		wmb();
347 
348 		old_value = *dbbuf_db;
349 		*dbbuf_db = value;
350 
351 		/*
352 		 * Ensure that the doorbell is updated before reading the event
353 		 * index from memory.  The controller needs to provide similar
354 		 * ordering to ensure the envent index is updated before reading
355 		 * the doorbell.
356 		 */
357 		mb();
358 
359 		if (!nvme_dbbuf_need_event(*dbbuf_ei, value, old_value))
360 			return false;
361 	}
362 
363 	return true;
364 }
365 
366 /*
367  * Will slightly overestimate the number of pages needed.  This is OK
368  * as it only leads to a small amount of wasted memory for the lifetime of
369  * the I/O.
370  */
371 static int nvme_pci_npages_prp(void)
372 {
373 	unsigned nprps = DIV_ROUND_UP(NVME_MAX_KB_SZ + NVME_CTRL_PAGE_SIZE,
374 				      NVME_CTRL_PAGE_SIZE);
375 	return DIV_ROUND_UP(8 * nprps, PAGE_SIZE - 8);
376 }
377 
378 /*
379  * Calculates the number of pages needed for the SGL segments. For example a 4k
380  * page can accommodate 256 SGL descriptors.
381  */
382 static int nvme_pci_npages_sgl(void)
383 {
384 	return DIV_ROUND_UP(NVME_MAX_SEGS * sizeof(struct nvme_sgl_desc),
385 			PAGE_SIZE);
386 }
387 
388 static size_t nvme_pci_iod_alloc_size(void)
389 {
390 	size_t npages = max(nvme_pci_npages_prp(), nvme_pci_npages_sgl());
391 
392 	return sizeof(__le64 *) * npages +
393 		sizeof(struct scatterlist) * NVME_MAX_SEGS;
394 }
395 
396 static int nvme_admin_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
397 				unsigned int hctx_idx)
398 {
399 	struct nvme_dev *dev = data;
400 	struct nvme_queue *nvmeq = &dev->queues[0];
401 
402 	WARN_ON(hctx_idx != 0);
403 	WARN_ON(dev->admin_tagset.tags[0] != hctx->tags);
404 
405 	hctx->driver_data = nvmeq;
406 	return 0;
407 }
408 
409 static int nvme_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
410 			  unsigned int hctx_idx)
411 {
412 	struct nvme_dev *dev = data;
413 	struct nvme_queue *nvmeq = &dev->queues[hctx_idx + 1];
414 
415 	WARN_ON(dev->tagset.tags[hctx_idx] != hctx->tags);
416 	hctx->driver_data = nvmeq;
417 	return 0;
418 }
419 
420 static int nvme_init_request(struct blk_mq_tag_set *set, struct request *req,
421 		unsigned int hctx_idx, unsigned int numa_node)
422 {
423 	struct nvme_dev *dev = set->driver_data;
424 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
425 	int queue_idx = (set == &dev->tagset) ? hctx_idx + 1 : 0;
426 	struct nvme_queue *nvmeq = &dev->queues[queue_idx];
427 
428 	BUG_ON(!nvmeq);
429 	iod->nvmeq = nvmeq;
430 
431 	nvme_req(req)->ctrl = &dev->ctrl;
432 	nvme_req(req)->cmd = &iod->cmd;
433 	return 0;
434 }
435 
436 static int queue_irq_offset(struct nvme_dev *dev)
437 {
438 	/* if we have more than 1 vec, admin queue offsets us by 1 */
439 	if (dev->num_vecs > 1)
440 		return 1;
441 
442 	return 0;
443 }
444 
445 static int nvme_pci_map_queues(struct blk_mq_tag_set *set)
446 {
447 	struct nvme_dev *dev = set->driver_data;
448 	int i, qoff, offset;
449 
450 	offset = queue_irq_offset(dev);
451 	for (i = 0, qoff = 0; i < set->nr_maps; i++) {
452 		struct blk_mq_queue_map *map = &set->map[i];
453 
454 		map->nr_queues = dev->io_queues[i];
455 		if (!map->nr_queues) {
456 			BUG_ON(i == HCTX_TYPE_DEFAULT);
457 			continue;
458 		}
459 
460 		/*
461 		 * The poll queue(s) doesn't have an IRQ (and hence IRQ
462 		 * affinity), so use the regular blk-mq cpu mapping
463 		 */
464 		map->queue_offset = qoff;
465 		if (i != HCTX_TYPE_POLL && offset)
466 			blk_mq_pci_map_queues(map, to_pci_dev(dev->dev), offset);
467 		else
468 			blk_mq_map_queues(map);
469 		qoff += map->nr_queues;
470 		offset += map->nr_queues;
471 	}
472 
473 	return 0;
474 }
475 
476 /*
477  * Write sq tail if we are asked to, or if the next command would wrap.
478  */
479 static inline void nvme_write_sq_db(struct nvme_queue *nvmeq, bool write_sq)
480 {
481 	if (!write_sq) {
482 		u16 next_tail = nvmeq->sq_tail + 1;
483 
484 		if (next_tail == nvmeq->q_depth)
485 			next_tail = 0;
486 		if (next_tail != nvmeq->last_sq_tail)
487 			return;
488 	}
489 
490 	if (nvme_dbbuf_update_and_check_event(nvmeq->sq_tail,
491 			nvmeq->dbbuf_sq_db, nvmeq->dbbuf_sq_ei))
492 		writel(nvmeq->sq_tail, nvmeq->q_db);
493 	nvmeq->last_sq_tail = nvmeq->sq_tail;
494 }
495 
496 /**
497  * nvme_submit_cmd() - Copy a command into a queue and ring the doorbell
498  * @nvmeq: The queue to use
499  * @cmd: The command to send
500  * @write_sq: whether to write to the SQ doorbell
501  */
502 static void nvme_submit_cmd(struct nvme_queue *nvmeq, struct nvme_command *cmd,
503 			    bool write_sq)
504 {
505 	spin_lock(&nvmeq->sq_lock);
506 	memcpy(nvmeq->sq_cmds + (nvmeq->sq_tail << nvmeq->sqes),
507 	       cmd, sizeof(*cmd));
508 	if (++nvmeq->sq_tail == nvmeq->q_depth)
509 		nvmeq->sq_tail = 0;
510 	nvme_write_sq_db(nvmeq, write_sq);
511 	spin_unlock(&nvmeq->sq_lock);
512 }
513 
514 static void nvme_commit_rqs(struct blk_mq_hw_ctx *hctx)
515 {
516 	struct nvme_queue *nvmeq = hctx->driver_data;
517 
518 	spin_lock(&nvmeq->sq_lock);
519 	if (nvmeq->sq_tail != nvmeq->last_sq_tail)
520 		nvme_write_sq_db(nvmeq, true);
521 	spin_unlock(&nvmeq->sq_lock);
522 }
523 
524 static void **nvme_pci_iod_list(struct request *req)
525 {
526 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
527 	return (void **)(iod->sg + blk_rq_nr_phys_segments(req));
528 }
529 
530 static inline bool nvme_pci_use_sgls(struct nvme_dev *dev, struct request *req)
531 {
532 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
533 	int nseg = blk_rq_nr_phys_segments(req);
534 	unsigned int avg_seg_size;
535 
536 	avg_seg_size = DIV_ROUND_UP(blk_rq_payload_bytes(req), nseg);
537 
538 	if (!nvme_ctrl_sgl_supported(&dev->ctrl))
539 		return false;
540 	if (!iod->nvmeq->qid)
541 		return false;
542 	if (!sgl_threshold || avg_seg_size < sgl_threshold)
543 		return false;
544 	return true;
545 }
546 
547 static void nvme_free_prps(struct nvme_dev *dev, struct request *req)
548 {
549 	const int last_prp = NVME_CTRL_PAGE_SIZE / sizeof(__le64) - 1;
550 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
551 	dma_addr_t dma_addr = iod->first_dma;
552 	int i;
553 
554 	for (i = 0; i < iod->npages; i++) {
555 		__le64 *prp_list = nvme_pci_iod_list(req)[i];
556 		dma_addr_t next_dma_addr = le64_to_cpu(prp_list[last_prp]);
557 
558 		dma_pool_free(dev->prp_page_pool, prp_list, dma_addr);
559 		dma_addr = next_dma_addr;
560 	}
561 }
562 
563 static void nvme_free_sgls(struct nvme_dev *dev, struct request *req)
564 {
565 	const int last_sg = SGES_PER_PAGE - 1;
566 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
567 	dma_addr_t dma_addr = iod->first_dma;
568 	int i;
569 
570 	for (i = 0; i < iod->npages; i++) {
571 		struct nvme_sgl_desc *sg_list = nvme_pci_iod_list(req)[i];
572 		dma_addr_t next_dma_addr = le64_to_cpu((sg_list[last_sg]).addr);
573 
574 		dma_pool_free(dev->prp_page_pool, sg_list, dma_addr);
575 		dma_addr = next_dma_addr;
576 	}
577 }
578 
579 static void nvme_unmap_sg(struct nvme_dev *dev, struct request *req)
580 {
581 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
582 
583 	if (is_pci_p2pdma_page(sg_page(iod->sg)))
584 		pci_p2pdma_unmap_sg(dev->dev, iod->sg, iod->nents,
585 				    rq_dma_dir(req));
586 	else
587 		dma_unmap_sg(dev->dev, iod->sg, iod->nents, rq_dma_dir(req));
588 }
589 
590 static void nvme_unmap_data(struct nvme_dev *dev, struct request *req)
591 {
592 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
593 
594 	if (iod->dma_len) {
595 		dma_unmap_page(dev->dev, iod->first_dma, iod->dma_len,
596 			       rq_dma_dir(req));
597 		return;
598 	}
599 
600 	WARN_ON_ONCE(!iod->nents);
601 
602 	nvme_unmap_sg(dev, req);
603 	if (iod->npages == 0)
604 		dma_pool_free(dev->prp_small_pool, nvme_pci_iod_list(req)[0],
605 			      iod->first_dma);
606 	else if (iod->use_sgl)
607 		nvme_free_sgls(dev, req);
608 	else
609 		nvme_free_prps(dev, req);
610 	mempool_free(iod->sg, dev->iod_mempool);
611 }
612 
613 static void nvme_print_sgl(struct scatterlist *sgl, int nents)
614 {
615 	int i;
616 	struct scatterlist *sg;
617 
618 	for_each_sg(sgl, sg, nents, i) {
619 		dma_addr_t phys = sg_phys(sg);
620 		pr_warn("sg[%d] phys_addr:%pad offset:%d length:%d "
621 			"dma_address:%pad dma_length:%d\n",
622 			i, &phys, sg->offset, sg->length, &sg_dma_address(sg),
623 			sg_dma_len(sg));
624 	}
625 }
626 
627 static blk_status_t nvme_pci_setup_prps(struct nvme_dev *dev,
628 		struct request *req, struct nvme_rw_command *cmnd)
629 {
630 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
631 	struct dma_pool *pool;
632 	int length = blk_rq_payload_bytes(req);
633 	struct scatterlist *sg = iod->sg;
634 	int dma_len = sg_dma_len(sg);
635 	u64 dma_addr = sg_dma_address(sg);
636 	int offset = dma_addr & (NVME_CTRL_PAGE_SIZE - 1);
637 	__le64 *prp_list;
638 	void **list = nvme_pci_iod_list(req);
639 	dma_addr_t prp_dma;
640 	int nprps, i;
641 
642 	length -= (NVME_CTRL_PAGE_SIZE - offset);
643 	if (length <= 0) {
644 		iod->first_dma = 0;
645 		goto done;
646 	}
647 
648 	dma_len -= (NVME_CTRL_PAGE_SIZE - offset);
649 	if (dma_len) {
650 		dma_addr += (NVME_CTRL_PAGE_SIZE - offset);
651 	} else {
652 		sg = sg_next(sg);
653 		dma_addr = sg_dma_address(sg);
654 		dma_len = sg_dma_len(sg);
655 	}
656 
657 	if (length <= NVME_CTRL_PAGE_SIZE) {
658 		iod->first_dma = dma_addr;
659 		goto done;
660 	}
661 
662 	nprps = DIV_ROUND_UP(length, NVME_CTRL_PAGE_SIZE);
663 	if (nprps <= (256 / 8)) {
664 		pool = dev->prp_small_pool;
665 		iod->npages = 0;
666 	} else {
667 		pool = dev->prp_page_pool;
668 		iod->npages = 1;
669 	}
670 
671 	prp_list = dma_pool_alloc(pool, GFP_ATOMIC, &prp_dma);
672 	if (!prp_list) {
673 		iod->first_dma = dma_addr;
674 		iod->npages = -1;
675 		return BLK_STS_RESOURCE;
676 	}
677 	list[0] = prp_list;
678 	iod->first_dma = prp_dma;
679 	i = 0;
680 	for (;;) {
681 		if (i == NVME_CTRL_PAGE_SIZE >> 3) {
682 			__le64 *old_prp_list = prp_list;
683 			prp_list = dma_pool_alloc(pool, GFP_ATOMIC, &prp_dma);
684 			if (!prp_list)
685 				goto free_prps;
686 			list[iod->npages++] = prp_list;
687 			prp_list[0] = old_prp_list[i - 1];
688 			old_prp_list[i - 1] = cpu_to_le64(prp_dma);
689 			i = 1;
690 		}
691 		prp_list[i++] = cpu_to_le64(dma_addr);
692 		dma_len -= NVME_CTRL_PAGE_SIZE;
693 		dma_addr += NVME_CTRL_PAGE_SIZE;
694 		length -= NVME_CTRL_PAGE_SIZE;
695 		if (length <= 0)
696 			break;
697 		if (dma_len > 0)
698 			continue;
699 		if (unlikely(dma_len < 0))
700 			goto bad_sgl;
701 		sg = sg_next(sg);
702 		dma_addr = sg_dma_address(sg);
703 		dma_len = sg_dma_len(sg);
704 	}
705 done:
706 	cmnd->dptr.prp1 = cpu_to_le64(sg_dma_address(iod->sg));
707 	cmnd->dptr.prp2 = cpu_to_le64(iod->first_dma);
708 	return BLK_STS_OK;
709 free_prps:
710 	nvme_free_prps(dev, req);
711 	return BLK_STS_RESOURCE;
712 bad_sgl:
713 	WARN(DO_ONCE(nvme_print_sgl, iod->sg, iod->nents),
714 			"Invalid SGL for payload:%d nents:%d\n",
715 			blk_rq_payload_bytes(req), iod->nents);
716 	return BLK_STS_IOERR;
717 }
718 
719 static void nvme_pci_sgl_set_data(struct nvme_sgl_desc *sge,
720 		struct scatterlist *sg)
721 {
722 	sge->addr = cpu_to_le64(sg_dma_address(sg));
723 	sge->length = cpu_to_le32(sg_dma_len(sg));
724 	sge->type = NVME_SGL_FMT_DATA_DESC << 4;
725 }
726 
727 static void nvme_pci_sgl_set_seg(struct nvme_sgl_desc *sge,
728 		dma_addr_t dma_addr, int entries)
729 {
730 	sge->addr = cpu_to_le64(dma_addr);
731 	if (entries < SGES_PER_PAGE) {
732 		sge->length = cpu_to_le32(entries * sizeof(*sge));
733 		sge->type = NVME_SGL_FMT_LAST_SEG_DESC << 4;
734 	} else {
735 		sge->length = cpu_to_le32(PAGE_SIZE);
736 		sge->type = NVME_SGL_FMT_SEG_DESC << 4;
737 	}
738 }
739 
740 static blk_status_t nvme_pci_setup_sgls(struct nvme_dev *dev,
741 		struct request *req, struct nvme_rw_command *cmd, int entries)
742 {
743 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
744 	struct dma_pool *pool;
745 	struct nvme_sgl_desc *sg_list;
746 	struct scatterlist *sg = iod->sg;
747 	dma_addr_t sgl_dma;
748 	int i = 0;
749 
750 	/* setting the transfer type as SGL */
751 	cmd->flags = NVME_CMD_SGL_METABUF;
752 
753 	if (entries == 1) {
754 		nvme_pci_sgl_set_data(&cmd->dptr.sgl, sg);
755 		return BLK_STS_OK;
756 	}
757 
758 	if (entries <= (256 / sizeof(struct nvme_sgl_desc))) {
759 		pool = dev->prp_small_pool;
760 		iod->npages = 0;
761 	} else {
762 		pool = dev->prp_page_pool;
763 		iod->npages = 1;
764 	}
765 
766 	sg_list = dma_pool_alloc(pool, GFP_ATOMIC, &sgl_dma);
767 	if (!sg_list) {
768 		iod->npages = -1;
769 		return BLK_STS_RESOURCE;
770 	}
771 
772 	nvme_pci_iod_list(req)[0] = sg_list;
773 	iod->first_dma = sgl_dma;
774 
775 	nvme_pci_sgl_set_seg(&cmd->dptr.sgl, sgl_dma, entries);
776 
777 	do {
778 		if (i == SGES_PER_PAGE) {
779 			struct nvme_sgl_desc *old_sg_desc = sg_list;
780 			struct nvme_sgl_desc *link = &old_sg_desc[i - 1];
781 
782 			sg_list = dma_pool_alloc(pool, GFP_ATOMIC, &sgl_dma);
783 			if (!sg_list)
784 				goto free_sgls;
785 
786 			i = 0;
787 			nvme_pci_iod_list(req)[iod->npages++] = sg_list;
788 			sg_list[i++] = *link;
789 			nvme_pci_sgl_set_seg(link, sgl_dma, entries);
790 		}
791 
792 		nvme_pci_sgl_set_data(&sg_list[i++], sg);
793 		sg = sg_next(sg);
794 	} while (--entries > 0);
795 
796 	return BLK_STS_OK;
797 free_sgls:
798 	nvme_free_sgls(dev, req);
799 	return BLK_STS_RESOURCE;
800 }
801 
802 static blk_status_t nvme_setup_prp_simple(struct nvme_dev *dev,
803 		struct request *req, struct nvme_rw_command *cmnd,
804 		struct bio_vec *bv)
805 {
806 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
807 	unsigned int offset = bv->bv_offset & (NVME_CTRL_PAGE_SIZE - 1);
808 	unsigned int first_prp_len = NVME_CTRL_PAGE_SIZE - offset;
809 
810 	iod->first_dma = dma_map_bvec(dev->dev, bv, rq_dma_dir(req), 0);
811 	if (dma_mapping_error(dev->dev, iod->first_dma))
812 		return BLK_STS_RESOURCE;
813 	iod->dma_len = bv->bv_len;
814 
815 	cmnd->dptr.prp1 = cpu_to_le64(iod->first_dma);
816 	if (bv->bv_len > first_prp_len)
817 		cmnd->dptr.prp2 = cpu_to_le64(iod->first_dma + first_prp_len);
818 	return BLK_STS_OK;
819 }
820 
821 static blk_status_t nvme_setup_sgl_simple(struct nvme_dev *dev,
822 		struct request *req, struct nvme_rw_command *cmnd,
823 		struct bio_vec *bv)
824 {
825 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
826 
827 	iod->first_dma = dma_map_bvec(dev->dev, bv, rq_dma_dir(req), 0);
828 	if (dma_mapping_error(dev->dev, iod->first_dma))
829 		return BLK_STS_RESOURCE;
830 	iod->dma_len = bv->bv_len;
831 
832 	cmnd->flags = NVME_CMD_SGL_METABUF;
833 	cmnd->dptr.sgl.addr = cpu_to_le64(iod->first_dma);
834 	cmnd->dptr.sgl.length = cpu_to_le32(iod->dma_len);
835 	cmnd->dptr.sgl.type = NVME_SGL_FMT_DATA_DESC << 4;
836 	return BLK_STS_OK;
837 }
838 
839 static blk_status_t nvme_map_data(struct nvme_dev *dev, struct request *req,
840 		struct nvme_command *cmnd)
841 {
842 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
843 	blk_status_t ret = BLK_STS_RESOURCE;
844 	int nr_mapped;
845 
846 	if (blk_rq_nr_phys_segments(req) == 1) {
847 		struct bio_vec bv = req_bvec(req);
848 
849 		if (!is_pci_p2pdma_page(bv.bv_page)) {
850 			if (bv.bv_offset + bv.bv_len <= NVME_CTRL_PAGE_SIZE * 2)
851 				return nvme_setup_prp_simple(dev, req,
852 							     &cmnd->rw, &bv);
853 
854 			if (iod->nvmeq->qid && sgl_threshold &&
855 			    nvme_ctrl_sgl_supported(&dev->ctrl))
856 				return nvme_setup_sgl_simple(dev, req,
857 							     &cmnd->rw, &bv);
858 		}
859 	}
860 
861 	iod->dma_len = 0;
862 	iod->sg = mempool_alloc(dev->iod_mempool, GFP_ATOMIC);
863 	if (!iod->sg)
864 		return BLK_STS_RESOURCE;
865 	sg_init_table(iod->sg, blk_rq_nr_phys_segments(req));
866 	iod->nents = blk_rq_map_sg(req->q, req, iod->sg);
867 	if (!iod->nents)
868 		goto out_free_sg;
869 
870 	if (is_pci_p2pdma_page(sg_page(iod->sg)))
871 		nr_mapped = pci_p2pdma_map_sg_attrs(dev->dev, iod->sg,
872 				iod->nents, rq_dma_dir(req), DMA_ATTR_NO_WARN);
873 	else
874 		nr_mapped = dma_map_sg_attrs(dev->dev, iod->sg, iod->nents,
875 					     rq_dma_dir(req), DMA_ATTR_NO_WARN);
876 	if (!nr_mapped)
877 		goto out_free_sg;
878 
879 	iod->use_sgl = nvme_pci_use_sgls(dev, req);
880 	if (iod->use_sgl)
881 		ret = nvme_pci_setup_sgls(dev, req, &cmnd->rw, nr_mapped);
882 	else
883 		ret = nvme_pci_setup_prps(dev, req, &cmnd->rw);
884 	if (ret != BLK_STS_OK)
885 		goto out_unmap_sg;
886 	return BLK_STS_OK;
887 
888 out_unmap_sg:
889 	nvme_unmap_sg(dev, req);
890 out_free_sg:
891 	mempool_free(iod->sg, dev->iod_mempool);
892 	return ret;
893 }
894 
895 static blk_status_t nvme_map_metadata(struct nvme_dev *dev, struct request *req,
896 		struct nvme_command *cmnd)
897 {
898 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
899 
900 	iod->meta_dma = dma_map_bvec(dev->dev, rq_integrity_vec(req),
901 			rq_dma_dir(req), 0);
902 	if (dma_mapping_error(dev->dev, iod->meta_dma))
903 		return BLK_STS_IOERR;
904 	cmnd->rw.metadata = cpu_to_le64(iod->meta_dma);
905 	return BLK_STS_OK;
906 }
907 
908 /*
909  * NOTE: ns is NULL when called on the admin queue.
910  */
911 static blk_status_t nvme_queue_rq(struct blk_mq_hw_ctx *hctx,
912 			 const struct blk_mq_queue_data *bd)
913 {
914 	struct nvme_ns *ns = hctx->queue->queuedata;
915 	struct nvme_queue *nvmeq = hctx->driver_data;
916 	struct nvme_dev *dev = nvmeq->dev;
917 	struct request *req = bd->rq;
918 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
919 	struct nvme_command *cmnd = &iod->cmd;
920 	blk_status_t ret;
921 
922 	iod->aborted = 0;
923 	iod->npages = -1;
924 	iod->nents = 0;
925 
926 	/*
927 	 * We should not need to do this, but we're still using this to
928 	 * ensure we can drain requests on a dying queue.
929 	 */
930 	if (unlikely(!test_bit(NVMEQ_ENABLED, &nvmeq->flags)))
931 		return BLK_STS_IOERR;
932 
933 	if (!nvme_check_ready(&dev->ctrl, req, true))
934 		return nvme_fail_nonready_command(&dev->ctrl, req);
935 
936 	ret = nvme_setup_cmd(ns, req);
937 	if (ret)
938 		return ret;
939 
940 	if (blk_rq_nr_phys_segments(req)) {
941 		ret = nvme_map_data(dev, req, cmnd);
942 		if (ret)
943 			goto out_free_cmd;
944 	}
945 
946 	if (blk_integrity_rq(req)) {
947 		ret = nvme_map_metadata(dev, req, cmnd);
948 		if (ret)
949 			goto out_unmap_data;
950 	}
951 
952 	blk_mq_start_request(req);
953 	nvme_submit_cmd(nvmeq, cmnd, bd->last);
954 	return BLK_STS_OK;
955 out_unmap_data:
956 	nvme_unmap_data(dev, req);
957 out_free_cmd:
958 	nvme_cleanup_cmd(req);
959 	return ret;
960 }
961 
962 static void nvme_pci_complete_rq(struct request *req)
963 {
964 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
965 	struct nvme_dev *dev = iod->nvmeq->dev;
966 
967 	if (blk_integrity_rq(req))
968 		dma_unmap_page(dev->dev, iod->meta_dma,
969 			       rq_integrity_vec(req)->bv_len, rq_data_dir(req));
970 	if (blk_rq_nr_phys_segments(req))
971 		nvme_unmap_data(dev, req);
972 	nvme_complete_rq(req);
973 }
974 
975 /* We read the CQE phase first to check if the rest of the entry is valid */
976 static inline bool nvme_cqe_pending(struct nvme_queue *nvmeq)
977 {
978 	struct nvme_completion *hcqe = &nvmeq->cqes[nvmeq->cq_head];
979 
980 	return (le16_to_cpu(READ_ONCE(hcqe->status)) & 1) == nvmeq->cq_phase;
981 }
982 
983 static inline void nvme_ring_cq_doorbell(struct nvme_queue *nvmeq)
984 {
985 	u16 head = nvmeq->cq_head;
986 
987 	if (nvme_dbbuf_update_and_check_event(head, nvmeq->dbbuf_cq_db,
988 					      nvmeq->dbbuf_cq_ei))
989 		writel(head, nvmeq->q_db + nvmeq->dev->db_stride);
990 }
991 
992 static inline struct blk_mq_tags *nvme_queue_tagset(struct nvme_queue *nvmeq)
993 {
994 	if (!nvmeq->qid)
995 		return nvmeq->dev->admin_tagset.tags[0];
996 	return nvmeq->dev->tagset.tags[nvmeq->qid - 1];
997 }
998 
999 static inline void nvme_handle_cqe(struct nvme_queue *nvmeq, u16 idx)
1000 {
1001 	struct nvme_completion *cqe = &nvmeq->cqes[idx];
1002 	__u16 command_id = READ_ONCE(cqe->command_id);
1003 	struct request *req;
1004 
1005 	/*
1006 	 * AEN requests are special as they don't time out and can
1007 	 * survive any kind of queue freeze and often don't respond to
1008 	 * aborts.  We don't even bother to allocate a struct request
1009 	 * for them but rather special case them here.
1010 	 */
1011 	if (unlikely(nvme_is_aen_req(nvmeq->qid, command_id))) {
1012 		nvme_complete_async_event(&nvmeq->dev->ctrl,
1013 				cqe->status, &cqe->result);
1014 		return;
1015 	}
1016 
1017 	req = blk_mq_tag_to_rq(nvme_queue_tagset(nvmeq), command_id);
1018 	if (unlikely(!req)) {
1019 		dev_warn(nvmeq->dev->ctrl.device,
1020 			"invalid id %d completed on queue %d\n",
1021 			command_id, le16_to_cpu(cqe->sq_id));
1022 		return;
1023 	}
1024 
1025 	trace_nvme_sq(req, cqe->sq_head, nvmeq->sq_tail);
1026 	if (!nvme_try_complete_req(req, cqe->status, cqe->result))
1027 		nvme_pci_complete_rq(req);
1028 }
1029 
1030 static inline void nvme_update_cq_head(struct nvme_queue *nvmeq)
1031 {
1032 	u32 tmp = nvmeq->cq_head + 1;
1033 
1034 	if (tmp == nvmeq->q_depth) {
1035 		nvmeq->cq_head = 0;
1036 		nvmeq->cq_phase ^= 1;
1037 	} else {
1038 		nvmeq->cq_head = tmp;
1039 	}
1040 }
1041 
1042 static inline int nvme_process_cq(struct nvme_queue *nvmeq)
1043 {
1044 	int found = 0;
1045 
1046 	while (nvme_cqe_pending(nvmeq)) {
1047 		found++;
1048 		/*
1049 		 * load-load control dependency between phase and the rest of
1050 		 * the cqe requires a full read memory barrier
1051 		 */
1052 		dma_rmb();
1053 		nvme_handle_cqe(nvmeq, nvmeq->cq_head);
1054 		nvme_update_cq_head(nvmeq);
1055 	}
1056 
1057 	if (found)
1058 		nvme_ring_cq_doorbell(nvmeq);
1059 	return found;
1060 }
1061 
1062 static irqreturn_t nvme_irq(int irq, void *data)
1063 {
1064 	struct nvme_queue *nvmeq = data;
1065 
1066 	if (nvme_process_cq(nvmeq))
1067 		return IRQ_HANDLED;
1068 	return IRQ_NONE;
1069 }
1070 
1071 static irqreturn_t nvme_irq_check(int irq, void *data)
1072 {
1073 	struct nvme_queue *nvmeq = data;
1074 
1075 	if (nvme_cqe_pending(nvmeq))
1076 		return IRQ_WAKE_THREAD;
1077 	return IRQ_NONE;
1078 }
1079 
1080 /*
1081  * Poll for completions for any interrupt driven queue
1082  * Can be called from any context.
1083  */
1084 static void nvme_poll_irqdisable(struct nvme_queue *nvmeq)
1085 {
1086 	struct pci_dev *pdev = to_pci_dev(nvmeq->dev->dev);
1087 
1088 	WARN_ON_ONCE(test_bit(NVMEQ_POLLED, &nvmeq->flags));
1089 
1090 	disable_irq(pci_irq_vector(pdev, nvmeq->cq_vector));
1091 	nvme_process_cq(nvmeq);
1092 	enable_irq(pci_irq_vector(pdev, nvmeq->cq_vector));
1093 }
1094 
1095 static int nvme_poll(struct blk_mq_hw_ctx *hctx)
1096 {
1097 	struct nvme_queue *nvmeq = hctx->driver_data;
1098 	bool found;
1099 
1100 	if (!nvme_cqe_pending(nvmeq))
1101 		return 0;
1102 
1103 	spin_lock(&nvmeq->cq_poll_lock);
1104 	found = nvme_process_cq(nvmeq);
1105 	spin_unlock(&nvmeq->cq_poll_lock);
1106 
1107 	return found;
1108 }
1109 
1110 static void nvme_pci_submit_async_event(struct nvme_ctrl *ctrl)
1111 {
1112 	struct nvme_dev *dev = to_nvme_dev(ctrl);
1113 	struct nvme_queue *nvmeq = &dev->queues[0];
1114 	struct nvme_command c = { };
1115 
1116 	c.common.opcode = nvme_admin_async_event;
1117 	c.common.command_id = NVME_AQ_BLK_MQ_DEPTH;
1118 	nvme_submit_cmd(nvmeq, &c, true);
1119 }
1120 
1121 static int adapter_delete_queue(struct nvme_dev *dev, u8 opcode, u16 id)
1122 {
1123 	struct nvme_command c = { };
1124 
1125 	c.delete_queue.opcode = opcode;
1126 	c.delete_queue.qid = cpu_to_le16(id);
1127 
1128 	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1129 }
1130 
1131 static int adapter_alloc_cq(struct nvme_dev *dev, u16 qid,
1132 		struct nvme_queue *nvmeq, s16 vector)
1133 {
1134 	struct nvme_command c = { };
1135 	int flags = NVME_QUEUE_PHYS_CONTIG;
1136 
1137 	if (!test_bit(NVMEQ_POLLED, &nvmeq->flags))
1138 		flags |= NVME_CQ_IRQ_ENABLED;
1139 
1140 	/*
1141 	 * Note: we (ab)use the fact that the prp fields survive if no data
1142 	 * is attached to the request.
1143 	 */
1144 	c.create_cq.opcode = nvme_admin_create_cq;
1145 	c.create_cq.prp1 = cpu_to_le64(nvmeq->cq_dma_addr);
1146 	c.create_cq.cqid = cpu_to_le16(qid);
1147 	c.create_cq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
1148 	c.create_cq.cq_flags = cpu_to_le16(flags);
1149 	c.create_cq.irq_vector = cpu_to_le16(vector);
1150 
1151 	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1152 }
1153 
1154 static int adapter_alloc_sq(struct nvme_dev *dev, u16 qid,
1155 						struct nvme_queue *nvmeq)
1156 {
1157 	struct nvme_ctrl *ctrl = &dev->ctrl;
1158 	struct nvme_command c = { };
1159 	int flags = NVME_QUEUE_PHYS_CONTIG;
1160 
1161 	/*
1162 	 * Some drives have a bug that auto-enables WRRU if MEDIUM isn't
1163 	 * set. Since URGENT priority is zeroes, it makes all queues
1164 	 * URGENT.
1165 	 */
1166 	if (ctrl->quirks & NVME_QUIRK_MEDIUM_PRIO_SQ)
1167 		flags |= NVME_SQ_PRIO_MEDIUM;
1168 
1169 	/*
1170 	 * Note: we (ab)use the fact that the prp fields survive if no data
1171 	 * is attached to the request.
1172 	 */
1173 	c.create_sq.opcode = nvme_admin_create_sq;
1174 	c.create_sq.prp1 = cpu_to_le64(nvmeq->sq_dma_addr);
1175 	c.create_sq.sqid = cpu_to_le16(qid);
1176 	c.create_sq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
1177 	c.create_sq.sq_flags = cpu_to_le16(flags);
1178 	c.create_sq.cqid = cpu_to_le16(qid);
1179 
1180 	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1181 }
1182 
1183 static int adapter_delete_cq(struct nvme_dev *dev, u16 cqid)
1184 {
1185 	return adapter_delete_queue(dev, nvme_admin_delete_cq, cqid);
1186 }
1187 
1188 static int adapter_delete_sq(struct nvme_dev *dev, u16 sqid)
1189 {
1190 	return adapter_delete_queue(dev, nvme_admin_delete_sq, sqid);
1191 }
1192 
1193 static void abort_endio(struct request *req, blk_status_t error)
1194 {
1195 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
1196 	struct nvme_queue *nvmeq = iod->nvmeq;
1197 
1198 	dev_warn(nvmeq->dev->ctrl.device,
1199 		 "Abort status: 0x%x", nvme_req(req)->status);
1200 	atomic_inc(&nvmeq->dev->ctrl.abort_limit);
1201 	blk_mq_free_request(req);
1202 }
1203 
1204 static bool nvme_should_reset(struct nvme_dev *dev, u32 csts)
1205 {
1206 	/* If true, indicates loss of adapter communication, possibly by a
1207 	 * NVMe Subsystem reset.
1208 	 */
1209 	bool nssro = dev->subsystem && (csts & NVME_CSTS_NSSRO);
1210 
1211 	/* If there is a reset/reinit ongoing, we shouldn't reset again. */
1212 	switch (dev->ctrl.state) {
1213 	case NVME_CTRL_RESETTING:
1214 	case NVME_CTRL_CONNECTING:
1215 		return false;
1216 	default:
1217 		break;
1218 	}
1219 
1220 	/* We shouldn't reset unless the controller is on fatal error state
1221 	 * _or_ if we lost the communication with it.
1222 	 */
1223 	if (!(csts & NVME_CSTS_CFS) && !nssro)
1224 		return false;
1225 
1226 	return true;
1227 }
1228 
1229 static void nvme_warn_reset(struct nvme_dev *dev, u32 csts)
1230 {
1231 	/* Read a config register to help see what died. */
1232 	u16 pci_status;
1233 	int result;
1234 
1235 	result = pci_read_config_word(to_pci_dev(dev->dev), PCI_STATUS,
1236 				      &pci_status);
1237 	if (result == PCIBIOS_SUCCESSFUL)
1238 		dev_warn(dev->ctrl.device,
1239 			 "controller is down; will reset: CSTS=0x%x, PCI_STATUS=0x%hx\n",
1240 			 csts, pci_status);
1241 	else
1242 		dev_warn(dev->ctrl.device,
1243 			 "controller is down; will reset: CSTS=0x%x, PCI_STATUS read failed (%d)\n",
1244 			 csts, result);
1245 }
1246 
1247 static enum blk_eh_timer_return nvme_timeout(struct request *req, bool reserved)
1248 {
1249 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
1250 	struct nvme_queue *nvmeq = iod->nvmeq;
1251 	struct nvme_dev *dev = nvmeq->dev;
1252 	struct request *abort_req;
1253 	struct nvme_command cmd = { };
1254 	u32 csts = readl(dev->bar + NVME_REG_CSTS);
1255 
1256 	/* If PCI error recovery process is happening, we cannot reset or
1257 	 * the recovery mechanism will surely fail.
1258 	 */
1259 	mb();
1260 	if (pci_channel_offline(to_pci_dev(dev->dev)))
1261 		return BLK_EH_RESET_TIMER;
1262 
1263 	/*
1264 	 * Reset immediately if the controller is failed
1265 	 */
1266 	if (nvme_should_reset(dev, csts)) {
1267 		nvme_warn_reset(dev, csts);
1268 		nvme_dev_disable(dev, false);
1269 		nvme_reset_ctrl(&dev->ctrl);
1270 		return BLK_EH_DONE;
1271 	}
1272 
1273 	/*
1274 	 * Did we miss an interrupt?
1275 	 */
1276 	if (test_bit(NVMEQ_POLLED, &nvmeq->flags))
1277 		nvme_poll(req->mq_hctx);
1278 	else
1279 		nvme_poll_irqdisable(nvmeq);
1280 
1281 	if (blk_mq_request_completed(req)) {
1282 		dev_warn(dev->ctrl.device,
1283 			 "I/O %d QID %d timeout, completion polled\n",
1284 			 req->tag, nvmeq->qid);
1285 		return BLK_EH_DONE;
1286 	}
1287 
1288 	/*
1289 	 * Shutdown immediately if controller times out while starting. The
1290 	 * reset work will see the pci device disabled when it gets the forced
1291 	 * cancellation error. All outstanding requests are completed on
1292 	 * shutdown, so we return BLK_EH_DONE.
1293 	 */
1294 	switch (dev->ctrl.state) {
1295 	case NVME_CTRL_CONNECTING:
1296 		nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DELETING);
1297 		fallthrough;
1298 	case NVME_CTRL_DELETING:
1299 		dev_warn_ratelimited(dev->ctrl.device,
1300 			 "I/O %d QID %d timeout, disable controller\n",
1301 			 req->tag, nvmeq->qid);
1302 		nvme_req(req)->flags |= NVME_REQ_CANCELLED;
1303 		nvme_dev_disable(dev, true);
1304 		return BLK_EH_DONE;
1305 	case NVME_CTRL_RESETTING:
1306 		return BLK_EH_RESET_TIMER;
1307 	default:
1308 		break;
1309 	}
1310 
1311 	/*
1312 	 * Shutdown the controller immediately and schedule a reset if the
1313 	 * command was already aborted once before and still hasn't been
1314 	 * returned to the driver, or if this is the admin queue.
1315 	 */
1316 	if (!nvmeq->qid || iod->aborted) {
1317 		dev_warn(dev->ctrl.device,
1318 			 "I/O %d QID %d timeout, reset controller\n",
1319 			 req->tag, nvmeq->qid);
1320 		nvme_req(req)->flags |= NVME_REQ_CANCELLED;
1321 		nvme_dev_disable(dev, false);
1322 		nvme_reset_ctrl(&dev->ctrl);
1323 
1324 		return BLK_EH_DONE;
1325 	}
1326 
1327 	if (atomic_dec_return(&dev->ctrl.abort_limit) < 0) {
1328 		atomic_inc(&dev->ctrl.abort_limit);
1329 		return BLK_EH_RESET_TIMER;
1330 	}
1331 	iod->aborted = 1;
1332 
1333 	cmd.abort.opcode = nvme_admin_abort_cmd;
1334 	cmd.abort.cid = req->tag;
1335 	cmd.abort.sqid = cpu_to_le16(nvmeq->qid);
1336 
1337 	dev_warn(nvmeq->dev->ctrl.device,
1338 		"I/O %d QID %d timeout, aborting\n",
1339 		 req->tag, nvmeq->qid);
1340 
1341 	abort_req = nvme_alloc_request(dev->ctrl.admin_q, &cmd,
1342 			BLK_MQ_REQ_NOWAIT);
1343 	if (IS_ERR(abort_req)) {
1344 		atomic_inc(&dev->ctrl.abort_limit);
1345 		return BLK_EH_RESET_TIMER;
1346 	}
1347 
1348 	abort_req->end_io_data = NULL;
1349 	blk_execute_rq_nowait(NULL, abort_req, 0, abort_endio);
1350 
1351 	/*
1352 	 * The aborted req will be completed on receiving the abort req.
1353 	 * We enable the timer again. If hit twice, it'll cause a device reset,
1354 	 * as the device then is in a faulty state.
1355 	 */
1356 	return BLK_EH_RESET_TIMER;
1357 }
1358 
1359 static void nvme_free_queue(struct nvme_queue *nvmeq)
1360 {
1361 	dma_free_coherent(nvmeq->dev->dev, CQ_SIZE(nvmeq),
1362 				(void *)nvmeq->cqes, nvmeq->cq_dma_addr);
1363 	if (!nvmeq->sq_cmds)
1364 		return;
1365 
1366 	if (test_and_clear_bit(NVMEQ_SQ_CMB, &nvmeq->flags)) {
1367 		pci_free_p2pmem(to_pci_dev(nvmeq->dev->dev),
1368 				nvmeq->sq_cmds, SQ_SIZE(nvmeq));
1369 	} else {
1370 		dma_free_coherent(nvmeq->dev->dev, SQ_SIZE(nvmeq),
1371 				nvmeq->sq_cmds, nvmeq->sq_dma_addr);
1372 	}
1373 }
1374 
1375 static void nvme_free_queues(struct nvme_dev *dev, int lowest)
1376 {
1377 	int i;
1378 
1379 	for (i = dev->ctrl.queue_count - 1; i >= lowest; i--) {
1380 		dev->ctrl.queue_count--;
1381 		nvme_free_queue(&dev->queues[i]);
1382 	}
1383 }
1384 
1385 /**
1386  * nvme_suspend_queue - put queue into suspended state
1387  * @nvmeq: queue to suspend
1388  */
1389 static int nvme_suspend_queue(struct nvme_queue *nvmeq)
1390 {
1391 	if (!test_and_clear_bit(NVMEQ_ENABLED, &nvmeq->flags))
1392 		return 1;
1393 
1394 	/* ensure that nvme_queue_rq() sees NVMEQ_ENABLED cleared */
1395 	mb();
1396 
1397 	nvmeq->dev->online_queues--;
1398 	if (!nvmeq->qid && nvmeq->dev->ctrl.admin_q)
1399 		blk_mq_quiesce_queue(nvmeq->dev->ctrl.admin_q);
1400 	if (!test_and_clear_bit(NVMEQ_POLLED, &nvmeq->flags))
1401 		pci_free_irq(to_pci_dev(nvmeq->dev->dev), nvmeq->cq_vector, nvmeq);
1402 	return 0;
1403 }
1404 
1405 static void nvme_suspend_io_queues(struct nvme_dev *dev)
1406 {
1407 	int i;
1408 
1409 	for (i = dev->ctrl.queue_count - 1; i > 0; i--)
1410 		nvme_suspend_queue(&dev->queues[i]);
1411 }
1412 
1413 static void nvme_disable_admin_queue(struct nvme_dev *dev, bool shutdown)
1414 {
1415 	struct nvme_queue *nvmeq = &dev->queues[0];
1416 
1417 	if (shutdown)
1418 		nvme_shutdown_ctrl(&dev->ctrl);
1419 	else
1420 		nvme_disable_ctrl(&dev->ctrl);
1421 
1422 	nvme_poll_irqdisable(nvmeq);
1423 }
1424 
1425 /*
1426  * Called only on a device that has been disabled and after all other threads
1427  * that can check this device's completion queues have synced, except
1428  * nvme_poll(). This is the last chance for the driver to see a natural
1429  * completion before nvme_cancel_request() terminates all incomplete requests.
1430  */
1431 static void nvme_reap_pending_cqes(struct nvme_dev *dev)
1432 {
1433 	int i;
1434 
1435 	for (i = dev->ctrl.queue_count - 1; i > 0; i--) {
1436 		spin_lock(&dev->queues[i].cq_poll_lock);
1437 		nvme_process_cq(&dev->queues[i]);
1438 		spin_unlock(&dev->queues[i].cq_poll_lock);
1439 	}
1440 }
1441 
1442 static int nvme_cmb_qdepth(struct nvme_dev *dev, int nr_io_queues,
1443 				int entry_size)
1444 {
1445 	int q_depth = dev->q_depth;
1446 	unsigned q_size_aligned = roundup(q_depth * entry_size,
1447 					  NVME_CTRL_PAGE_SIZE);
1448 
1449 	if (q_size_aligned * nr_io_queues > dev->cmb_size) {
1450 		u64 mem_per_q = div_u64(dev->cmb_size, nr_io_queues);
1451 
1452 		mem_per_q = round_down(mem_per_q, NVME_CTRL_PAGE_SIZE);
1453 		q_depth = div_u64(mem_per_q, entry_size);
1454 
1455 		/*
1456 		 * Ensure the reduced q_depth is above some threshold where it
1457 		 * would be better to map queues in system memory with the
1458 		 * original depth
1459 		 */
1460 		if (q_depth < 64)
1461 			return -ENOMEM;
1462 	}
1463 
1464 	return q_depth;
1465 }
1466 
1467 static int nvme_alloc_sq_cmds(struct nvme_dev *dev, struct nvme_queue *nvmeq,
1468 				int qid)
1469 {
1470 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1471 
1472 	if (qid && dev->cmb_use_sqes && (dev->cmbsz & NVME_CMBSZ_SQS)) {
1473 		nvmeq->sq_cmds = pci_alloc_p2pmem(pdev, SQ_SIZE(nvmeq));
1474 		if (nvmeq->sq_cmds) {
1475 			nvmeq->sq_dma_addr = pci_p2pmem_virt_to_bus(pdev,
1476 							nvmeq->sq_cmds);
1477 			if (nvmeq->sq_dma_addr) {
1478 				set_bit(NVMEQ_SQ_CMB, &nvmeq->flags);
1479 				return 0;
1480 			}
1481 
1482 			pci_free_p2pmem(pdev, nvmeq->sq_cmds, SQ_SIZE(nvmeq));
1483 		}
1484 	}
1485 
1486 	nvmeq->sq_cmds = dma_alloc_coherent(dev->dev, SQ_SIZE(nvmeq),
1487 				&nvmeq->sq_dma_addr, GFP_KERNEL);
1488 	if (!nvmeq->sq_cmds)
1489 		return -ENOMEM;
1490 	return 0;
1491 }
1492 
1493 static int nvme_alloc_queue(struct nvme_dev *dev, int qid, int depth)
1494 {
1495 	struct nvme_queue *nvmeq = &dev->queues[qid];
1496 
1497 	if (dev->ctrl.queue_count > qid)
1498 		return 0;
1499 
1500 	nvmeq->sqes = qid ? dev->io_sqes : NVME_ADM_SQES;
1501 	nvmeq->q_depth = depth;
1502 	nvmeq->cqes = dma_alloc_coherent(dev->dev, CQ_SIZE(nvmeq),
1503 					 &nvmeq->cq_dma_addr, GFP_KERNEL);
1504 	if (!nvmeq->cqes)
1505 		goto free_nvmeq;
1506 
1507 	if (nvme_alloc_sq_cmds(dev, nvmeq, qid))
1508 		goto free_cqdma;
1509 
1510 	nvmeq->dev = dev;
1511 	spin_lock_init(&nvmeq->sq_lock);
1512 	spin_lock_init(&nvmeq->cq_poll_lock);
1513 	nvmeq->cq_head = 0;
1514 	nvmeq->cq_phase = 1;
1515 	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
1516 	nvmeq->qid = qid;
1517 	dev->ctrl.queue_count++;
1518 
1519 	return 0;
1520 
1521  free_cqdma:
1522 	dma_free_coherent(dev->dev, CQ_SIZE(nvmeq), (void *)nvmeq->cqes,
1523 			  nvmeq->cq_dma_addr);
1524  free_nvmeq:
1525 	return -ENOMEM;
1526 }
1527 
1528 static int queue_request_irq(struct nvme_queue *nvmeq)
1529 {
1530 	struct pci_dev *pdev = to_pci_dev(nvmeq->dev->dev);
1531 	int nr = nvmeq->dev->ctrl.instance;
1532 
1533 	if (use_threaded_interrupts) {
1534 		return pci_request_irq(pdev, nvmeq->cq_vector, nvme_irq_check,
1535 				nvme_irq, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
1536 	} else {
1537 		return pci_request_irq(pdev, nvmeq->cq_vector, nvme_irq,
1538 				NULL, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
1539 	}
1540 }
1541 
1542 static void nvme_init_queue(struct nvme_queue *nvmeq, u16 qid)
1543 {
1544 	struct nvme_dev *dev = nvmeq->dev;
1545 
1546 	nvmeq->sq_tail = 0;
1547 	nvmeq->last_sq_tail = 0;
1548 	nvmeq->cq_head = 0;
1549 	nvmeq->cq_phase = 1;
1550 	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
1551 	memset((void *)nvmeq->cqes, 0, CQ_SIZE(nvmeq));
1552 	nvme_dbbuf_init(dev, nvmeq, qid);
1553 	dev->online_queues++;
1554 	wmb(); /* ensure the first interrupt sees the initialization */
1555 }
1556 
1557 /*
1558  * Try getting shutdown_lock while setting up IO queues.
1559  */
1560 static int nvme_setup_io_queues_trylock(struct nvme_dev *dev)
1561 {
1562 	/*
1563 	 * Give up if the lock is being held by nvme_dev_disable.
1564 	 */
1565 	if (!mutex_trylock(&dev->shutdown_lock))
1566 		return -ENODEV;
1567 
1568 	/*
1569 	 * Controller is in wrong state, fail early.
1570 	 */
1571 	if (dev->ctrl.state != NVME_CTRL_CONNECTING) {
1572 		mutex_unlock(&dev->shutdown_lock);
1573 		return -ENODEV;
1574 	}
1575 
1576 	return 0;
1577 }
1578 
1579 static int nvme_create_queue(struct nvme_queue *nvmeq, int qid, bool polled)
1580 {
1581 	struct nvme_dev *dev = nvmeq->dev;
1582 	int result;
1583 	u16 vector = 0;
1584 
1585 	clear_bit(NVMEQ_DELETE_ERROR, &nvmeq->flags);
1586 
1587 	/*
1588 	 * A queue's vector matches the queue identifier unless the controller
1589 	 * has only one vector available.
1590 	 */
1591 	if (!polled)
1592 		vector = dev->num_vecs == 1 ? 0 : qid;
1593 	else
1594 		set_bit(NVMEQ_POLLED, &nvmeq->flags);
1595 
1596 	result = adapter_alloc_cq(dev, qid, nvmeq, vector);
1597 	if (result)
1598 		return result;
1599 
1600 	result = adapter_alloc_sq(dev, qid, nvmeq);
1601 	if (result < 0)
1602 		return result;
1603 	if (result)
1604 		goto release_cq;
1605 
1606 	nvmeq->cq_vector = vector;
1607 
1608 	result = nvme_setup_io_queues_trylock(dev);
1609 	if (result)
1610 		return result;
1611 	nvme_init_queue(nvmeq, qid);
1612 	if (!polled) {
1613 		result = queue_request_irq(nvmeq);
1614 		if (result < 0)
1615 			goto release_sq;
1616 	}
1617 
1618 	set_bit(NVMEQ_ENABLED, &nvmeq->flags);
1619 	mutex_unlock(&dev->shutdown_lock);
1620 	return result;
1621 
1622 release_sq:
1623 	dev->online_queues--;
1624 	mutex_unlock(&dev->shutdown_lock);
1625 	adapter_delete_sq(dev, qid);
1626 release_cq:
1627 	adapter_delete_cq(dev, qid);
1628 	return result;
1629 }
1630 
1631 static const struct blk_mq_ops nvme_mq_admin_ops = {
1632 	.queue_rq	= nvme_queue_rq,
1633 	.complete	= nvme_pci_complete_rq,
1634 	.init_hctx	= nvme_admin_init_hctx,
1635 	.init_request	= nvme_init_request,
1636 	.timeout	= nvme_timeout,
1637 };
1638 
1639 static const struct blk_mq_ops nvme_mq_ops = {
1640 	.queue_rq	= nvme_queue_rq,
1641 	.complete	= nvme_pci_complete_rq,
1642 	.commit_rqs	= nvme_commit_rqs,
1643 	.init_hctx	= nvme_init_hctx,
1644 	.init_request	= nvme_init_request,
1645 	.map_queues	= nvme_pci_map_queues,
1646 	.timeout	= nvme_timeout,
1647 	.poll		= nvme_poll,
1648 };
1649 
1650 static void nvme_dev_remove_admin(struct nvme_dev *dev)
1651 {
1652 	if (dev->ctrl.admin_q && !blk_queue_dying(dev->ctrl.admin_q)) {
1653 		/*
1654 		 * If the controller was reset during removal, it's possible
1655 		 * user requests may be waiting on a stopped queue. Start the
1656 		 * queue to flush these to completion.
1657 		 */
1658 		blk_mq_unquiesce_queue(dev->ctrl.admin_q);
1659 		blk_cleanup_queue(dev->ctrl.admin_q);
1660 		blk_mq_free_tag_set(&dev->admin_tagset);
1661 	}
1662 }
1663 
1664 static int nvme_alloc_admin_tags(struct nvme_dev *dev)
1665 {
1666 	if (!dev->ctrl.admin_q) {
1667 		dev->admin_tagset.ops = &nvme_mq_admin_ops;
1668 		dev->admin_tagset.nr_hw_queues = 1;
1669 
1670 		dev->admin_tagset.queue_depth = NVME_AQ_MQ_TAG_DEPTH;
1671 		dev->admin_tagset.timeout = NVME_ADMIN_TIMEOUT;
1672 		dev->admin_tagset.numa_node = dev->ctrl.numa_node;
1673 		dev->admin_tagset.cmd_size = sizeof(struct nvme_iod);
1674 		dev->admin_tagset.flags = BLK_MQ_F_NO_SCHED;
1675 		dev->admin_tagset.driver_data = dev;
1676 
1677 		if (blk_mq_alloc_tag_set(&dev->admin_tagset))
1678 			return -ENOMEM;
1679 		dev->ctrl.admin_tagset = &dev->admin_tagset;
1680 
1681 		dev->ctrl.admin_q = blk_mq_init_queue(&dev->admin_tagset);
1682 		if (IS_ERR(dev->ctrl.admin_q)) {
1683 			blk_mq_free_tag_set(&dev->admin_tagset);
1684 			return -ENOMEM;
1685 		}
1686 		if (!blk_get_queue(dev->ctrl.admin_q)) {
1687 			nvme_dev_remove_admin(dev);
1688 			dev->ctrl.admin_q = NULL;
1689 			return -ENODEV;
1690 		}
1691 	} else
1692 		blk_mq_unquiesce_queue(dev->ctrl.admin_q);
1693 
1694 	return 0;
1695 }
1696 
1697 static unsigned long db_bar_size(struct nvme_dev *dev, unsigned nr_io_queues)
1698 {
1699 	return NVME_REG_DBS + ((nr_io_queues + 1) * 8 * dev->db_stride);
1700 }
1701 
1702 static int nvme_remap_bar(struct nvme_dev *dev, unsigned long size)
1703 {
1704 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1705 
1706 	if (size <= dev->bar_mapped_size)
1707 		return 0;
1708 	if (size > pci_resource_len(pdev, 0))
1709 		return -ENOMEM;
1710 	if (dev->bar)
1711 		iounmap(dev->bar);
1712 	dev->bar = ioremap(pci_resource_start(pdev, 0), size);
1713 	if (!dev->bar) {
1714 		dev->bar_mapped_size = 0;
1715 		return -ENOMEM;
1716 	}
1717 	dev->bar_mapped_size = size;
1718 	dev->dbs = dev->bar + NVME_REG_DBS;
1719 
1720 	return 0;
1721 }
1722 
1723 static int nvme_pci_configure_admin_queue(struct nvme_dev *dev)
1724 {
1725 	int result;
1726 	u32 aqa;
1727 	struct nvme_queue *nvmeq;
1728 
1729 	result = nvme_remap_bar(dev, db_bar_size(dev, 0));
1730 	if (result < 0)
1731 		return result;
1732 
1733 	dev->subsystem = readl(dev->bar + NVME_REG_VS) >= NVME_VS(1, 1, 0) ?
1734 				NVME_CAP_NSSRC(dev->ctrl.cap) : 0;
1735 
1736 	if (dev->subsystem &&
1737 	    (readl(dev->bar + NVME_REG_CSTS) & NVME_CSTS_NSSRO))
1738 		writel(NVME_CSTS_NSSRO, dev->bar + NVME_REG_CSTS);
1739 
1740 	result = nvme_disable_ctrl(&dev->ctrl);
1741 	if (result < 0)
1742 		return result;
1743 
1744 	result = nvme_alloc_queue(dev, 0, NVME_AQ_DEPTH);
1745 	if (result)
1746 		return result;
1747 
1748 	dev->ctrl.numa_node = dev_to_node(dev->dev);
1749 
1750 	nvmeq = &dev->queues[0];
1751 	aqa = nvmeq->q_depth - 1;
1752 	aqa |= aqa << 16;
1753 
1754 	writel(aqa, dev->bar + NVME_REG_AQA);
1755 	lo_hi_writeq(nvmeq->sq_dma_addr, dev->bar + NVME_REG_ASQ);
1756 	lo_hi_writeq(nvmeq->cq_dma_addr, dev->bar + NVME_REG_ACQ);
1757 
1758 	result = nvme_enable_ctrl(&dev->ctrl);
1759 	if (result)
1760 		return result;
1761 
1762 	nvmeq->cq_vector = 0;
1763 	nvme_init_queue(nvmeq, 0);
1764 	result = queue_request_irq(nvmeq);
1765 	if (result) {
1766 		dev->online_queues--;
1767 		return result;
1768 	}
1769 
1770 	set_bit(NVMEQ_ENABLED, &nvmeq->flags);
1771 	return result;
1772 }
1773 
1774 static int nvme_create_io_queues(struct nvme_dev *dev)
1775 {
1776 	unsigned i, max, rw_queues;
1777 	int ret = 0;
1778 
1779 	for (i = dev->ctrl.queue_count; i <= dev->max_qid; i++) {
1780 		if (nvme_alloc_queue(dev, i, dev->q_depth)) {
1781 			ret = -ENOMEM;
1782 			break;
1783 		}
1784 	}
1785 
1786 	max = min(dev->max_qid, dev->ctrl.queue_count - 1);
1787 	if (max != 1 && dev->io_queues[HCTX_TYPE_POLL]) {
1788 		rw_queues = dev->io_queues[HCTX_TYPE_DEFAULT] +
1789 				dev->io_queues[HCTX_TYPE_READ];
1790 	} else {
1791 		rw_queues = max;
1792 	}
1793 
1794 	for (i = dev->online_queues; i <= max; i++) {
1795 		bool polled = i > rw_queues;
1796 
1797 		ret = nvme_create_queue(&dev->queues[i], i, polled);
1798 		if (ret)
1799 			break;
1800 	}
1801 
1802 	/*
1803 	 * Ignore failing Create SQ/CQ commands, we can continue with less
1804 	 * than the desired amount of queues, and even a controller without
1805 	 * I/O queues can still be used to issue admin commands.  This might
1806 	 * be useful to upgrade a buggy firmware for example.
1807 	 */
1808 	return ret >= 0 ? 0 : ret;
1809 }
1810 
1811 static ssize_t nvme_cmb_show(struct device *dev,
1812 			     struct device_attribute *attr,
1813 			     char *buf)
1814 {
1815 	struct nvme_dev *ndev = to_nvme_dev(dev_get_drvdata(dev));
1816 
1817 	return scnprintf(buf, PAGE_SIZE, "cmbloc : x%08x\ncmbsz  : x%08x\n",
1818 		       ndev->cmbloc, ndev->cmbsz);
1819 }
1820 static DEVICE_ATTR(cmb, S_IRUGO, nvme_cmb_show, NULL);
1821 
1822 static u64 nvme_cmb_size_unit(struct nvme_dev *dev)
1823 {
1824 	u8 szu = (dev->cmbsz >> NVME_CMBSZ_SZU_SHIFT) & NVME_CMBSZ_SZU_MASK;
1825 
1826 	return 1ULL << (12 + 4 * szu);
1827 }
1828 
1829 static u32 nvme_cmb_size(struct nvme_dev *dev)
1830 {
1831 	return (dev->cmbsz >> NVME_CMBSZ_SZ_SHIFT) & NVME_CMBSZ_SZ_MASK;
1832 }
1833 
1834 static void nvme_map_cmb(struct nvme_dev *dev)
1835 {
1836 	u64 size, offset;
1837 	resource_size_t bar_size;
1838 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1839 	int bar;
1840 
1841 	if (dev->cmb_size)
1842 		return;
1843 
1844 	if (NVME_CAP_CMBS(dev->ctrl.cap))
1845 		writel(NVME_CMBMSC_CRE, dev->bar + NVME_REG_CMBMSC);
1846 
1847 	dev->cmbsz = readl(dev->bar + NVME_REG_CMBSZ);
1848 	if (!dev->cmbsz)
1849 		return;
1850 	dev->cmbloc = readl(dev->bar + NVME_REG_CMBLOC);
1851 
1852 	size = nvme_cmb_size_unit(dev) * nvme_cmb_size(dev);
1853 	offset = nvme_cmb_size_unit(dev) * NVME_CMB_OFST(dev->cmbloc);
1854 	bar = NVME_CMB_BIR(dev->cmbloc);
1855 	bar_size = pci_resource_len(pdev, bar);
1856 
1857 	if (offset > bar_size)
1858 		return;
1859 
1860 	/*
1861 	 * Tell the controller about the host side address mapping the CMB,
1862 	 * and enable CMB decoding for the NVMe 1.4+ scheme:
1863 	 */
1864 	if (NVME_CAP_CMBS(dev->ctrl.cap)) {
1865 		hi_lo_writeq(NVME_CMBMSC_CRE | NVME_CMBMSC_CMSE |
1866 			     (pci_bus_address(pdev, bar) + offset),
1867 			     dev->bar + NVME_REG_CMBMSC);
1868 	}
1869 
1870 	/*
1871 	 * Controllers may support a CMB size larger than their BAR,
1872 	 * for example, due to being behind a bridge. Reduce the CMB to
1873 	 * the reported size of the BAR
1874 	 */
1875 	if (size > bar_size - offset)
1876 		size = bar_size - offset;
1877 
1878 	if (pci_p2pdma_add_resource(pdev, bar, size, offset)) {
1879 		dev_warn(dev->ctrl.device,
1880 			 "failed to register the CMB\n");
1881 		return;
1882 	}
1883 
1884 	dev->cmb_size = size;
1885 	dev->cmb_use_sqes = use_cmb_sqes && (dev->cmbsz & NVME_CMBSZ_SQS);
1886 
1887 	if ((dev->cmbsz & (NVME_CMBSZ_WDS | NVME_CMBSZ_RDS)) ==
1888 			(NVME_CMBSZ_WDS | NVME_CMBSZ_RDS))
1889 		pci_p2pmem_publish(pdev, true);
1890 
1891 	if (sysfs_add_file_to_group(&dev->ctrl.device->kobj,
1892 				    &dev_attr_cmb.attr, NULL))
1893 		dev_warn(dev->ctrl.device,
1894 			 "failed to add sysfs attribute for CMB\n");
1895 }
1896 
1897 static inline void nvme_release_cmb(struct nvme_dev *dev)
1898 {
1899 	if (dev->cmb_size) {
1900 		sysfs_remove_file_from_group(&dev->ctrl.device->kobj,
1901 					     &dev_attr_cmb.attr, NULL);
1902 		dev->cmb_size = 0;
1903 	}
1904 }
1905 
1906 static int nvme_set_host_mem(struct nvme_dev *dev, u32 bits)
1907 {
1908 	u32 host_mem_size = dev->host_mem_size >> NVME_CTRL_PAGE_SHIFT;
1909 	u64 dma_addr = dev->host_mem_descs_dma;
1910 	struct nvme_command c = { };
1911 	int ret;
1912 
1913 	c.features.opcode	= nvme_admin_set_features;
1914 	c.features.fid		= cpu_to_le32(NVME_FEAT_HOST_MEM_BUF);
1915 	c.features.dword11	= cpu_to_le32(bits);
1916 	c.features.dword12	= cpu_to_le32(host_mem_size);
1917 	c.features.dword13	= cpu_to_le32(lower_32_bits(dma_addr));
1918 	c.features.dword14	= cpu_to_le32(upper_32_bits(dma_addr));
1919 	c.features.dword15	= cpu_to_le32(dev->nr_host_mem_descs);
1920 
1921 	ret = nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1922 	if (ret) {
1923 		dev_warn(dev->ctrl.device,
1924 			 "failed to set host mem (err %d, flags %#x).\n",
1925 			 ret, bits);
1926 	}
1927 	return ret;
1928 }
1929 
1930 static void nvme_free_host_mem(struct nvme_dev *dev)
1931 {
1932 	int i;
1933 
1934 	for (i = 0; i < dev->nr_host_mem_descs; i++) {
1935 		struct nvme_host_mem_buf_desc *desc = &dev->host_mem_descs[i];
1936 		size_t size = le32_to_cpu(desc->size) * NVME_CTRL_PAGE_SIZE;
1937 
1938 		dma_free_attrs(dev->dev, size, dev->host_mem_desc_bufs[i],
1939 			       le64_to_cpu(desc->addr),
1940 			       DMA_ATTR_NO_KERNEL_MAPPING | DMA_ATTR_NO_WARN);
1941 	}
1942 
1943 	kfree(dev->host_mem_desc_bufs);
1944 	dev->host_mem_desc_bufs = NULL;
1945 	dma_free_coherent(dev->dev,
1946 			dev->nr_host_mem_descs * sizeof(*dev->host_mem_descs),
1947 			dev->host_mem_descs, dev->host_mem_descs_dma);
1948 	dev->host_mem_descs = NULL;
1949 	dev->nr_host_mem_descs = 0;
1950 }
1951 
1952 static int __nvme_alloc_host_mem(struct nvme_dev *dev, u64 preferred,
1953 		u32 chunk_size)
1954 {
1955 	struct nvme_host_mem_buf_desc *descs;
1956 	u32 max_entries, len;
1957 	dma_addr_t descs_dma;
1958 	int i = 0;
1959 	void **bufs;
1960 	u64 size, tmp;
1961 
1962 	tmp = (preferred + chunk_size - 1);
1963 	do_div(tmp, chunk_size);
1964 	max_entries = tmp;
1965 
1966 	if (dev->ctrl.hmmaxd && dev->ctrl.hmmaxd < max_entries)
1967 		max_entries = dev->ctrl.hmmaxd;
1968 
1969 	descs = dma_alloc_coherent(dev->dev, max_entries * sizeof(*descs),
1970 				   &descs_dma, GFP_KERNEL);
1971 	if (!descs)
1972 		goto out;
1973 
1974 	bufs = kcalloc(max_entries, sizeof(*bufs), GFP_KERNEL);
1975 	if (!bufs)
1976 		goto out_free_descs;
1977 
1978 	for (size = 0; size < preferred && i < max_entries; size += len) {
1979 		dma_addr_t dma_addr;
1980 
1981 		len = min_t(u64, chunk_size, preferred - size);
1982 		bufs[i] = dma_alloc_attrs(dev->dev, len, &dma_addr, GFP_KERNEL,
1983 				DMA_ATTR_NO_KERNEL_MAPPING | DMA_ATTR_NO_WARN);
1984 		if (!bufs[i])
1985 			break;
1986 
1987 		descs[i].addr = cpu_to_le64(dma_addr);
1988 		descs[i].size = cpu_to_le32(len / NVME_CTRL_PAGE_SIZE);
1989 		i++;
1990 	}
1991 
1992 	if (!size)
1993 		goto out_free_bufs;
1994 
1995 	dev->nr_host_mem_descs = i;
1996 	dev->host_mem_size = size;
1997 	dev->host_mem_descs = descs;
1998 	dev->host_mem_descs_dma = descs_dma;
1999 	dev->host_mem_desc_bufs = bufs;
2000 	return 0;
2001 
2002 out_free_bufs:
2003 	while (--i >= 0) {
2004 		size_t size = le32_to_cpu(descs[i].size) * NVME_CTRL_PAGE_SIZE;
2005 
2006 		dma_free_attrs(dev->dev, size, bufs[i],
2007 			       le64_to_cpu(descs[i].addr),
2008 			       DMA_ATTR_NO_KERNEL_MAPPING | DMA_ATTR_NO_WARN);
2009 	}
2010 
2011 	kfree(bufs);
2012 out_free_descs:
2013 	dma_free_coherent(dev->dev, max_entries * sizeof(*descs), descs,
2014 			descs_dma);
2015 out:
2016 	dev->host_mem_descs = NULL;
2017 	return -ENOMEM;
2018 }
2019 
2020 static int nvme_alloc_host_mem(struct nvme_dev *dev, u64 min, u64 preferred)
2021 {
2022 	u64 min_chunk = min_t(u64, preferred, PAGE_SIZE * MAX_ORDER_NR_PAGES);
2023 	u64 hmminds = max_t(u32, dev->ctrl.hmminds * 4096, PAGE_SIZE * 2);
2024 	u64 chunk_size;
2025 
2026 	/* start big and work our way down */
2027 	for (chunk_size = min_chunk; chunk_size >= hmminds; chunk_size /= 2) {
2028 		if (!__nvme_alloc_host_mem(dev, preferred, chunk_size)) {
2029 			if (!min || dev->host_mem_size >= min)
2030 				return 0;
2031 			nvme_free_host_mem(dev);
2032 		}
2033 	}
2034 
2035 	return -ENOMEM;
2036 }
2037 
2038 static int nvme_setup_host_mem(struct nvme_dev *dev)
2039 {
2040 	u64 max = (u64)max_host_mem_size_mb * SZ_1M;
2041 	u64 preferred = (u64)dev->ctrl.hmpre * 4096;
2042 	u64 min = (u64)dev->ctrl.hmmin * 4096;
2043 	u32 enable_bits = NVME_HOST_MEM_ENABLE;
2044 	int ret;
2045 
2046 	preferred = min(preferred, max);
2047 	if (min > max) {
2048 		dev_warn(dev->ctrl.device,
2049 			"min host memory (%lld MiB) above limit (%d MiB).\n",
2050 			min >> ilog2(SZ_1M), max_host_mem_size_mb);
2051 		nvme_free_host_mem(dev);
2052 		return 0;
2053 	}
2054 
2055 	/*
2056 	 * If we already have a buffer allocated check if we can reuse it.
2057 	 */
2058 	if (dev->host_mem_descs) {
2059 		if (dev->host_mem_size >= min)
2060 			enable_bits |= NVME_HOST_MEM_RETURN;
2061 		else
2062 			nvme_free_host_mem(dev);
2063 	}
2064 
2065 	if (!dev->host_mem_descs) {
2066 		if (nvme_alloc_host_mem(dev, min, preferred)) {
2067 			dev_warn(dev->ctrl.device,
2068 				"failed to allocate host memory buffer.\n");
2069 			return 0; /* controller must work without HMB */
2070 		}
2071 
2072 		dev_info(dev->ctrl.device,
2073 			"allocated %lld MiB host memory buffer.\n",
2074 			dev->host_mem_size >> ilog2(SZ_1M));
2075 	}
2076 
2077 	ret = nvme_set_host_mem(dev, enable_bits);
2078 	if (ret)
2079 		nvme_free_host_mem(dev);
2080 	return ret;
2081 }
2082 
2083 /*
2084  * nirqs is the number of interrupts available for write and read
2085  * queues. The core already reserved an interrupt for the admin queue.
2086  */
2087 static void nvme_calc_irq_sets(struct irq_affinity *affd, unsigned int nrirqs)
2088 {
2089 	struct nvme_dev *dev = affd->priv;
2090 	unsigned int nr_read_queues, nr_write_queues = dev->nr_write_queues;
2091 
2092 	/*
2093 	 * If there is no interrupt available for queues, ensure that
2094 	 * the default queue is set to 1. The affinity set size is
2095 	 * also set to one, but the irq core ignores it for this case.
2096 	 *
2097 	 * If only one interrupt is available or 'write_queue' == 0, combine
2098 	 * write and read queues.
2099 	 *
2100 	 * If 'write_queues' > 0, ensure it leaves room for at least one read
2101 	 * queue.
2102 	 */
2103 	if (!nrirqs) {
2104 		nrirqs = 1;
2105 		nr_read_queues = 0;
2106 	} else if (nrirqs == 1 || !nr_write_queues) {
2107 		nr_read_queues = 0;
2108 	} else if (nr_write_queues >= nrirqs) {
2109 		nr_read_queues = 1;
2110 	} else {
2111 		nr_read_queues = nrirqs - nr_write_queues;
2112 	}
2113 
2114 	dev->io_queues[HCTX_TYPE_DEFAULT] = nrirqs - nr_read_queues;
2115 	affd->set_size[HCTX_TYPE_DEFAULT] = nrirqs - nr_read_queues;
2116 	dev->io_queues[HCTX_TYPE_READ] = nr_read_queues;
2117 	affd->set_size[HCTX_TYPE_READ] = nr_read_queues;
2118 	affd->nr_sets = nr_read_queues ? 2 : 1;
2119 }
2120 
2121 static int nvme_setup_irqs(struct nvme_dev *dev, unsigned int nr_io_queues)
2122 {
2123 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2124 	struct irq_affinity affd = {
2125 		.pre_vectors	= 1,
2126 		.calc_sets	= nvme_calc_irq_sets,
2127 		.priv		= dev,
2128 	};
2129 	unsigned int irq_queues, poll_queues;
2130 
2131 	/*
2132 	 * Poll queues don't need interrupts, but we need at least one I/O queue
2133 	 * left over for non-polled I/O.
2134 	 */
2135 	poll_queues = min(dev->nr_poll_queues, nr_io_queues - 1);
2136 	dev->io_queues[HCTX_TYPE_POLL] = poll_queues;
2137 
2138 	/*
2139 	 * Initialize for the single interrupt case, will be updated in
2140 	 * nvme_calc_irq_sets().
2141 	 */
2142 	dev->io_queues[HCTX_TYPE_DEFAULT] = 1;
2143 	dev->io_queues[HCTX_TYPE_READ] = 0;
2144 
2145 	/*
2146 	 * We need interrupts for the admin queue and each non-polled I/O queue,
2147 	 * but some Apple controllers require all queues to use the first
2148 	 * vector.
2149 	 */
2150 	irq_queues = 1;
2151 	if (!(dev->ctrl.quirks & NVME_QUIRK_SINGLE_VECTOR))
2152 		irq_queues += (nr_io_queues - poll_queues);
2153 	return pci_alloc_irq_vectors_affinity(pdev, 1, irq_queues,
2154 			      PCI_IRQ_ALL_TYPES | PCI_IRQ_AFFINITY, &affd);
2155 }
2156 
2157 static void nvme_disable_io_queues(struct nvme_dev *dev)
2158 {
2159 	if (__nvme_disable_io_queues(dev, nvme_admin_delete_sq))
2160 		__nvme_disable_io_queues(dev, nvme_admin_delete_cq);
2161 }
2162 
2163 static unsigned int nvme_max_io_queues(struct nvme_dev *dev)
2164 {
2165 	/*
2166 	 * If tags are shared with admin queue (Apple bug), then
2167 	 * make sure we only use one IO queue.
2168 	 */
2169 	if (dev->ctrl.quirks & NVME_QUIRK_SHARED_TAGS)
2170 		return 1;
2171 	return num_possible_cpus() + dev->nr_write_queues + dev->nr_poll_queues;
2172 }
2173 
2174 static int nvme_setup_io_queues(struct nvme_dev *dev)
2175 {
2176 	struct nvme_queue *adminq = &dev->queues[0];
2177 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2178 	unsigned int nr_io_queues;
2179 	unsigned long size;
2180 	int result;
2181 
2182 	/*
2183 	 * Sample the module parameters once at reset time so that we have
2184 	 * stable values to work with.
2185 	 */
2186 	dev->nr_write_queues = write_queues;
2187 	dev->nr_poll_queues = poll_queues;
2188 
2189 	nr_io_queues = dev->nr_allocated_queues - 1;
2190 	result = nvme_set_queue_count(&dev->ctrl, &nr_io_queues);
2191 	if (result < 0)
2192 		return result;
2193 
2194 	if (nr_io_queues == 0)
2195 		return 0;
2196 
2197 	/*
2198 	 * Free IRQ resources as soon as NVMEQ_ENABLED bit transitions
2199 	 * from set to unset. If there is a window to it is truely freed,
2200 	 * pci_free_irq_vectors() jumping into this window will crash.
2201 	 * And take lock to avoid racing with pci_free_irq_vectors() in
2202 	 * nvme_dev_disable() path.
2203 	 */
2204 	result = nvme_setup_io_queues_trylock(dev);
2205 	if (result)
2206 		return result;
2207 	if (test_and_clear_bit(NVMEQ_ENABLED, &adminq->flags))
2208 		pci_free_irq(pdev, 0, adminq);
2209 
2210 	if (dev->cmb_use_sqes) {
2211 		result = nvme_cmb_qdepth(dev, nr_io_queues,
2212 				sizeof(struct nvme_command));
2213 		if (result > 0)
2214 			dev->q_depth = result;
2215 		else
2216 			dev->cmb_use_sqes = false;
2217 	}
2218 
2219 	do {
2220 		size = db_bar_size(dev, nr_io_queues);
2221 		result = nvme_remap_bar(dev, size);
2222 		if (!result)
2223 			break;
2224 		if (!--nr_io_queues) {
2225 			result = -ENOMEM;
2226 			goto out_unlock;
2227 		}
2228 	} while (1);
2229 	adminq->q_db = dev->dbs;
2230 
2231  retry:
2232 	/* Deregister the admin queue's interrupt */
2233 	if (test_and_clear_bit(NVMEQ_ENABLED, &adminq->flags))
2234 		pci_free_irq(pdev, 0, adminq);
2235 
2236 	/*
2237 	 * If we enable msix early due to not intx, disable it again before
2238 	 * setting up the full range we need.
2239 	 */
2240 	pci_free_irq_vectors(pdev);
2241 
2242 	result = nvme_setup_irqs(dev, nr_io_queues);
2243 	if (result <= 0) {
2244 		result = -EIO;
2245 		goto out_unlock;
2246 	}
2247 
2248 	dev->num_vecs = result;
2249 	result = max(result - 1, 1);
2250 	dev->max_qid = result + dev->io_queues[HCTX_TYPE_POLL];
2251 
2252 	/*
2253 	 * Should investigate if there's a performance win from allocating
2254 	 * more queues than interrupt vectors; it might allow the submission
2255 	 * path to scale better, even if the receive path is limited by the
2256 	 * number of interrupts.
2257 	 */
2258 	result = queue_request_irq(adminq);
2259 	if (result)
2260 		goto out_unlock;
2261 	set_bit(NVMEQ_ENABLED, &adminq->flags);
2262 	mutex_unlock(&dev->shutdown_lock);
2263 
2264 	result = nvme_create_io_queues(dev);
2265 	if (result || dev->online_queues < 2)
2266 		return result;
2267 
2268 	if (dev->online_queues - 1 < dev->max_qid) {
2269 		nr_io_queues = dev->online_queues - 1;
2270 		nvme_disable_io_queues(dev);
2271 		result = nvme_setup_io_queues_trylock(dev);
2272 		if (result)
2273 			return result;
2274 		nvme_suspend_io_queues(dev);
2275 		goto retry;
2276 	}
2277 	dev_info(dev->ctrl.device, "%d/%d/%d default/read/poll queues\n",
2278 					dev->io_queues[HCTX_TYPE_DEFAULT],
2279 					dev->io_queues[HCTX_TYPE_READ],
2280 					dev->io_queues[HCTX_TYPE_POLL]);
2281 	return 0;
2282 out_unlock:
2283 	mutex_unlock(&dev->shutdown_lock);
2284 	return result;
2285 }
2286 
2287 static void nvme_del_queue_end(struct request *req, blk_status_t error)
2288 {
2289 	struct nvme_queue *nvmeq = req->end_io_data;
2290 
2291 	blk_mq_free_request(req);
2292 	complete(&nvmeq->delete_done);
2293 }
2294 
2295 static void nvme_del_cq_end(struct request *req, blk_status_t error)
2296 {
2297 	struct nvme_queue *nvmeq = req->end_io_data;
2298 
2299 	if (error)
2300 		set_bit(NVMEQ_DELETE_ERROR, &nvmeq->flags);
2301 
2302 	nvme_del_queue_end(req, error);
2303 }
2304 
2305 static int nvme_delete_queue(struct nvme_queue *nvmeq, u8 opcode)
2306 {
2307 	struct request_queue *q = nvmeq->dev->ctrl.admin_q;
2308 	struct request *req;
2309 	struct nvme_command cmd = { };
2310 
2311 	cmd.delete_queue.opcode = opcode;
2312 	cmd.delete_queue.qid = cpu_to_le16(nvmeq->qid);
2313 
2314 	req = nvme_alloc_request(q, &cmd, BLK_MQ_REQ_NOWAIT);
2315 	if (IS_ERR(req))
2316 		return PTR_ERR(req);
2317 
2318 	req->end_io_data = nvmeq;
2319 
2320 	init_completion(&nvmeq->delete_done);
2321 	blk_execute_rq_nowait(NULL, req, false,
2322 			opcode == nvme_admin_delete_cq ?
2323 				nvme_del_cq_end : nvme_del_queue_end);
2324 	return 0;
2325 }
2326 
2327 static bool __nvme_disable_io_queues(struct nvme_dev *dev, u8 opcode)
2328 {
2329 	int nr_queues = dev->online_queues - 1, sent = 0;
2330 	unsigned long timeout;
2331 
2332  retry:
2333 	timeout = NVME_ADMIN_TIMEOUT;
2334 	while (nr_queues > 0) {
2335 		if (nvme_delete_queue(&dev->queues[nr_queues], opcode))
2336 			break;
2337 		nr_queues--;
2338 		sent++;
2339 	}
2340 	while (sent) {
2341 		struct nvme_queue *nvmeq = &dev->queues[nr_queues + sent];
2342 
2343 		timeout = wait_for_completion_io_timeout(&nvmeq->delete_done,
2344 				timeout);
2345 		if (timeout == 0)
2346 			return false;
2347 
2348 		sent--;
2349 		if (nr_queues)
2350 			goto retry;
2351 	}
2352 	return true;
2353 }
2354 
2355 static void nvme_dev_add(struct nvme_dev *dev)
2356 {
2357 	int ret;
2358 
2359 	if (!dev->ctrl.tagset) {
2360 		dev->tagset.ops = &nvme_mq_ops;
2361 		dev->tagset.nr_hw_queues = dev->online_queues - 1;
2362 		dev->tagset.nr_maps = 2; /* default + read */
2363 		if (dev->io_queues[HCTX_TYPE_POLL])
2364 			dev->tagset.nr_maps++;
2365 		dev->tagset.timeout = NVME_IO_TIMEOUT;
2366 		dev->tagset.numa_node = dev->ctrl.numa_node;
2367 		dev->tagset.queue_depth = min_t(unsigned int, dev->q_depth,
2368 						BLK_MQ_MAX_DEPTH) - 1;
2369 		dev->tagset.cmd_size = sizeof(struct nvme_iod);
2370 		dev->tagset.flags = BLK_MQ_F_SHOULD_MERGE;
2371 		dev->tagset.driver_data = dev;
2372 
2373 		/*
2374 		 * Some Apple controllers requires tags to be unique
2375 		 * across admin and IO queue, so reserve the first 32
2376 		 * tags of the IO queue.
2377 		 */
2378 		if (dev->ctrl.quirks & NVME_QUIRK_SHARED_TAGS)
2379 			dev->tagset.reserved_tags = NVME_AQ_DEPTH;
2380 
2381 		ret = blk_mq_alloc_tag_set(&dev->tagset);
2382 		if (ret) {
2383 			dev_warn(dev->ctrl.device,
2384 				"IO queues tagset allocation failed %d\n", ret);
2385 			return;
2386 		}
2387 		dev->ctrl.tagset = &dev->tagset;
2388 	} else {
2389 		blk_mq_update_nr_hw_queues(&dev->tagset, dev->online_queues - 1);
2390 
2391 		/* Free previously allocated queues that are no longer usable */
2392 		nvme_free_queues(dev, dev->online_queues);
2393 	}
2394 
2395 	nvme_dbbuf_set(dev);
2396 }
2397 
2398 static int nvme_pci_enable(struct nvme_dev *dev)
2399 {
2400 	int result = -ENOMEM;
2401 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2402 	int dma_address_bits = 64;
2403 
2404 	if (pci_enable_device_mem(pdev))
2405 		return result;
2406 
2407 	pci_set_master(pdev);
2408 
2409 	if (dev->ctrl.quirks & NVME_QUIRK_DMA_ADDRESS_BITS_48)
2410 		dma_address_bits = 48;
2411 	if (dma_set_mask_and_coherent(dev->dev, DMA_BIT_MASK(dma_address_bits)))
2412 		goto disable;
2413 
2414 	if (readl(dev->bar + NVME_REG_CSTS) == -1) {
2415 		result = -ENODEV;
2416 		goto disable;
2417 	}
2418 
2419 	/*
2420 	 * Some devices and/or platforms don't advertise or work with INTx
2421 	 * interrupts. Pre-enable a single MSIX or MSI vec for setup. We'll
2422 	 * adjust this later.
2423 	 */
2424 	result = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
2425 	if (result < 0)
2426 		return result;
2427 
2428 	dev->ctrl.cap = lo_hi_readq(dev->bar + NVME_REG_CAP);
2429 
2430 	dev->q_depth = min_t(u32, NVME_CAP_MQES(dev->ctrl.cap) + 1,
2431 				io_queue_depth);
2432 	dev->ctrl.sqsize = dev->q_depth - 1; /* 0's based queue depth */
2433 	dev->db_stride = 1 << NVME_CAP_STRIDE(dev->ctrl.cap);
2434 	dev->dbs = dev->bar + 4096;
2435 
2436 	/*
2437 	 * Some Apple controllers require a non-standard SQE size.
2438 	 * Interestingly they also seem to ignore the CC:IOSQES register
2439 	 * so we don't bother updating it here.
2440 	 */
2441 	if (dev->ctrl.quirks & NVME_QUIRK_128_BYTES_SQES)
2442 		dev->io_sqes = 7;
2443 	else
2444 		dev->io_sqes = NVME_NVM_IOSQES;
2445 
2446 	/*
2447 	 * Temporary fix for the Apple controller found in the MacBook8,1 and
2448 	 * some MacBook7,1 to avoid controller resets and data loss.
2449 	 */
2450 	if (pdev->vendor == PCI_VENDOR_ID_APPLE && pdev->device == 0x2001) {
2451 		dev->q_depth = 2;
2452 		dev_warn(dev->ctrl.device, "detected Apple NVMe controller, "
2453 			"set queue depth=%u to work around controller resets\n",
2454 			dev->q_depth);
2455 	} else if (pdev->vendor == PCI_VENDOR_ID_SAMSUNG &&
2456 		   (pdev->device == 0xa821 || pdev->device == 0xa822) &&
2457 		   NVME_CAP_MQES(dev->ctrl.cap) == 0) {
2458 		dev->q_depth = 64;
2459 		dev_err(dev->ctrl.device, "detected PM1725 NVMe controller, "
2460                         "set queue depth=%u\n", dev->q_depth);
2461 	}
2462 
2463 	/*
2464 	 * Controllers with the shared tags quirk need the IO queue to be
2465 	 * big enough so that we get 32 tags for the admin queue
2466 	 */
2467 	if ((dev->ctrl.quirks & NVME_QUIRK_SHARED_TAGS) &&
2468 	    (dev->q_depth < (NVME_AQ_DEPTH + 2))) {
2469 		dev->q_depth = NVME_AQ_DEPTH + 2;
2470 		dev_warn(dev->ctrl.device, "IO queue depth clamped to %d\n",
2471 			 dev->q_depth);
2472 	}
2473 
2474 
2475 	nvme_map_cmb(dev);
2476 
2477 	pci_enable_pcie_error_reporting(pdev);
2478 	pci_save_state(pdev);
2479 	return 0;
2480 
2481  disable:
2482 	pci_disable_device(pdev);
2483 	return result;
2484 }
2485 
2486 static void nvme_dev_unmap(struct nvme_dev *dev)
2487 {
2488 	if (dev->bar)
2489 		iounmap(dev->bar);
2490 	pci_release_mem_regions(to_pci_dev(dev->dev));
2491 }
2492 
2493 static void nvme_pci_disable(struct nvme_dev *dev)
2494 {
2495 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2496 
2497 	pci_free_irq_vectors(pdev);
2498 
2499 	if (pci_is_enabled(pdev)) {
2500 		pci_disable_pcie_error_reporting(pdev);
2501 		pci_disable_device(pdev);
2502 	}
2503 }
2504 
2505 static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown)
2506 {
2507 	bool dead = true, freeze = false;
2508 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2509 
2510 	mutex_lock(&dev->shutdown_lock);
2511 	if (pci_is_enabled(pdev)) {
2512 		u32 csts = readl(dev->bar + NVME_REG_CSTS);
2513 
2514 		if (dev->ctrl.state == NVME_CTRL_LIVE ||
2515 		    dev->ctrl.state == NVME_CTRL_RESETTING) {
2516 			freeze = true;
2517 			nvme_start_freeze(&dev->ctrl);
2518 		}
2519 		dead = !!((csts & NVME_CSTS_CFS) || !(csts & NVME_CSTS_RDY) ||
2520 			pdev->error_state  != pci_channel_io_normal);
2521 	}
2522 
2523 	/*
2524 	 * Give the controller a chance to complete all entered requests if
2525 	 * doing a safe shutdown.
2526 	 */
2527 	if (!dead && shutdown && freeze)
2528 		nvme_wait_freeze_timeout(&dev->ctrl, NVME_IO_TIMEOUT);
2529 
2530 	nvme_stop_queues(&dev->ctrl);
2531 
2532 	if (!dead && dev->ctrl.queue_count > 0) {
2533 		nvme_disable_io_queues(dev);
2534 		nvme_disable_admin_queue(dev, shutdown);
2535 	}
2536 	nvme_suspend_io_queues(dev);
2537 	nvme_suspend_queue(&dev->queues[0]);
2538 	nvme_pci_disable(dev);
2539 	nvme_reap_pending_cqes(dev);
2540 
2541 	blk_mq_tagset_busy_iter(&dev->tagset, nvme_cancel_request, &dev->ctrl);
2542 	blk_mq_tagset_busy_iter(&dev->admin_tagset, nvme_cancel_request, &dev->ctrl);
2543 	blk_mq_tagset_wait_completed_request(&dev->tagset);
2544 	blk_mq_tagset_wait_completed_request(&dev->admin_tagset);
2545 
2546 	/*
2547 	 * The driver will not be starting up queues again if shutting down so
2548 	 * must flush all entered requests to their failed completion to avoid
2549 	 * deadlocking blk-mq hot-cpu notifier.
2550 	 */
2551 	if (shutdown) {
2552 		nvme_start_queues(&dev->ctrl);
2553 		if (dev->ctrl.admin_q && !blk_queue_dying(dev->ctrl.admin_q))
2554 			blk_mq_unquiesce_queue(dev->ctrl.admin_q);
2555 	}
2556 	mutex_unlock(&dev->shutdown_lock);
2557 }
2558 
2559 static int nvme_disable_prepare_reset(struct nvme_dev *dev, bool shutdown)
2560 {
2561 	if (!nvme_wait_reset(&dev->ctrl))
2562 		return -EBUSY;
2563 	nvme_dev_disable(dev, shutdown);
2564 	return 0;
2565 }
2566 
2567 static int nvme_setup_prp_pools(struct nvme_dev *dev)
2568 {
2569 	dev->prp_page_pool = dma_pool_create("prp list page", dev->dev,
2570 						NVME_CTRL_PAGE_SIZE,
2571 						NVME_CTRL_PAGE_SIZE, 0);
2572 	if (!dev->prp_page_pool)
2573 		return -ENOMEM;
2574 
2575 	/* Optimisation for I/Os between 4k and 128k */
2576 	dev->prp_small_pool = dma_pool_create("prp list 256", dev->dev,
2577 						256, 256, 0);
2578 	if (!dev->prp_small_pool) {
2579 		dma_pool_destroy(dev->prp_page_pool);
2580 		return -ENOMEM;
2581 	}
2582 	return 0;
2583 }
2584 
2585 static void nvme_release_prp_pools(struct nvme_dev *dev)
2586 {
2587 	dma_pool_destroy(dev->prp_page_pool);
2588 	dma_pool_destroy(dev->prp_small_pool);
2589 }
2590 
2591 static void nvme_free_tagset(struct nvme_dev *dev)
2592 {
2593 	if (dev->tagset.tags)
2594 		blk_mq_free_tag_set(&dev->tagset);
2595 	dev->ctrl.tagset = NULL;
2596 }
2597 
2598 static void nvme_pci_free_ctrl(struct nvme_ctrl *ctrl)
2599 {
2600 	struct nvme_dev *dev = to_nvme_dev(ctrl);
2601 
2602 	nvme_dbbuf_dma_free(dev);
2603 	nvme_free_tagset(dev);
2604 	if (dev->ctrl.admin_q)
2605 		blk_put_queue(dev->ctrl.admin_q);
2606 	free_opal_dev(dev->ctrl.opal_dev);
2607 	mempool_destroy(dev->iod_mempool);
2608 	put_device(dev->dev);
2609 	kfree(dev->queues);
2610 	kfree(dev);
2611 }
2612 
2613 static void nvme_remove_dead_ctrl(struct nvme_dev *dev)
2614 {
2615 	/*
2616 	 * Set state to deleting now to avoid blocking nvme_wait_reset(), which
2617 	 * may be holding this pci_dev's device lock.
2618 	 */
2619 	nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DELETING);
2620 	nvme_get_ctrl(&dev->ctrl);
2621 	nvme_dev_disable(dev, false);
2622 	nvme_kill_queues(&dev->ctrl);
2623 	if (!queue_work(nvme_wq, &dev->remove_work))
2624 		nvme_put_ctrl(&dev->ctrl);
2625 }
2626 
2627 static void nvme_reset_work(struct work_struct *work)
2628 {
2629 	struct nvme_dev *dev =
2630 		container_of(work, struct nvme_dev, ctrl.reset_work);
2631 	bool was_suspend = !!(dev->ctrl.ctrl_config & NVME_CC_SHN_NORMAL);
2632 	int result;
2633 
2634 	if (dev->ctrl.state != NVME_CTRL_RESETTING) {
2635 		dev_warn(dev->ctrl.device, "ctrl state %d is not RESETTING\n",
2636 			 dev->ctrl.state);
2637 		result = -ENODEV;
2638 		goto out;
2639 	}
2640 
2641 	/*
2642 	 * If we're called to reset a live controller first shut it down before
2643 	 * moving on.
2644 	 */
2645 	if (dev->ctrl.ctrl_config & NVME_CC_ENABLE)
2646 		nvme_dev_disable(dev, false);
2647 	nvme_sync_queues(&dev->ctrl);
2648 
2649 	mutex_lock(&dev->shutdown_lock);
2650 	result = nvme_pci_enable(dev);
2651 	if (result)
2652 		goto out_unlock;
2653 
2654 	result = nvme_pci_configure_admin_queue(dev);
2655 	if (result)
2656 		goto out_unlock;
2657 
2658 	result = nvme_alloc_admin_tags(dev);
2659 	if (result)
2660 		goto out_unlock;
2661 
2662 	/*
2663 	 * Limit the max command size to prevent iod->sg allocations going
2664 	 * over a single page.
2665 	 */
2666 	dev->ctrl.max_hw_sectors = min_t(u32,
2667 		NVME_MAX_KB_SZ << 1, dma_max_mapping_size(dev->dev) >> 9);
2668 	dev->ctrl.max_segments = NVME_MAX_SEGS;
2669 
2670 	/*
2671 	 * Don't limit the IOMMU merged segment size.
2672 	 */
2673 	dma_set_max_seg_size(dev->dev, 0xffffffff);
2674 	dma_set_min_align_mask(dev->dev, NVME_CTRL_PAGE_SIZE - 1);
2675 
2676 	mutex_unlock(&dev->shutdown_lock);
2677 
2678 	/*
2679 	 * Introduce CONNECTING state from nvme-fc/rdma transports to mark the
2680 	 * initializing procedure here.
2681 	 */
2682 	if (!nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_CONNECTING)) {
2683 		dev_warn(dev->ctrl.device,
2684 			"failed to mark controller CONNECTING\n");
2685 		result = -EBUSY;
2686 		goto out;
2687 	}
2688 
2689 	/*
2690 	 * We do not support an SGL for metadata (yet), so we are limited to a
2691 	 * single integrity segment for the separate metadata pointer.
2692 	 */
2693 	dev->ctrl.max_integrity_segments = 1;
2694 
2695 	result = nvme_init_ctrl_finish(&dev->ctrl);
2696 	if (result)
2697 		goto out;
2698 
2699 	if (dev->ctrl.oacs & NVME_CTRL_OACS_SEC_SUPP) {
2700 		if (!dev->ctrl.opal_dev)
2701 			dev->ctrl.opal_dev =
2702 				init_opal_dev(&dev->ctrl, &nvme_sec_submit);
2703 		else if (was_suspend)
2704 			opal_unlock_from_suspend(dev->ctrl.opal_dev);
2705 	} else {
2706 		free_opal_dev(dev->ctrl.opal_dev);
2707 		dev->ctrl.opal_dev = NULL;
2708 	}
2709 
2710 	if (dev->ctrl.oacs & NVME_CTRL_OACS_DBBUF_SUPP) {
2711 		result = nvme_dbbuf_dma_alloc(dev);
2712 		if (result)
2713 			dev_warn(dev->dev,
2714 				 "unable to allocate dma for dbbuf\n");
2715 	}
2716 
2717 	if (dev->ctrl.hmpre) {
2718 		result = nvme_setup_host_mem(dev);
2719 		if (result < 0)
2720 			goto out;
2721 	}
2722 
2723 	result = nvme_setup_io_queues(dev);
2724 	if (result)
2725 		goto out;
2726 
2727 	/*
2728 	 * Keep the controller around but remove all namespaces if we don't have
2729 	 * any working I/O queue.
2730 	 */
2731 	if (dev->online_queues < 2) {
2732 		dev_warn(dev->ctrl.device, "IO queues not created\n");
2733 		nvme_kill_queues(&dev->ctrl);
2734 		nvme_remove_namespaces(&dev->ctrl);
2735 		nvme_free_tagset(dev);
2736 	} else {
2737 		nvme_start_queues(&dev->ctrl);
2738 		nvme_wait_freeze(&dev->ctrl);
2739 		nvme_dev_add(dev);
2740 		nvme_unfreeze(&dev->ctrl);
2741 	}
2742 
2743 	/*
2744 	 * If only admin queue live, keep it to do further investigation or
2745 	 * recovery.
2746 	 */
2747 	if (!nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_LIVE)) {
2748 		dev_warn(dev->ctrl.device,
2749 			"failed to mark controller live state\n");
2750 		result = -ENODEV;
2751 		goto out;
2752 	}
2753 
2754 	nvme_start_ctrl(&dev->ctrl);
2755 	return;
2756 
2757  out_unlock:
2758 	mutex_unlock(&dev->shutdown_lock);
2759  out:
2760 	if (result)
2761 		dev_warn(dev->ctrl.device,
2762 			 "Removing after probe failure status: %d\n", result);
2763 	nvme_remove_dead_ctrl(dev);
2764 }
2765 
2766 static void nvme_remove_dead_ctrl_work(struct work_struct *work)
2767 {
2768 	struct nvme_dev *dev = container_of(work, struct nvme_dev, remove_work);
2769 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2770 
2771 	if (pci_get_drvdata(pdev))
2772 		device_release_driver(&pdev->dev);
2773 	nvme_put_ctrl(&dev->ctrl);
2774 }
2775 
2776 static int nvme_pci_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val)
2777 {
2778 	*val = readl(to_nvme_dev(ctrl)->bar + off);
2779 	return 0;
2780 }
2781 
2782 static int nvme_pci_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val)
2783 {
2784 	writel(val, to_nvme_dev(ctrl)->bar + off);
2785 	return 0;
2786 }
2787 
2788 static int nvme_pci_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val)
2789 {
2790 	*val = lo_hi_readq(to_nvme_dev(ctrl)->bar + off);
2791 	return 0;
2792 }
2793 
2794 static int nvme_pci_get_address(struct nvme_ctrl *ctrl, char *buf, int size)
2795 {
2796 	struct pci_dev *pdev = to_pci_dev(to_nvme_dev(ctrl)->dev);
2797 
2798 	return snprintf(buf, size, "%s\n", dev_name(&pdev->dev));
2799 }
2800 
2801 static const struct nvme_ctrl_ops nvme_pci_ctrl_ops = {
2802 	.name			= "pcie",
2803 	.module			= THIS_MODULE,
2804 	.flags			= NVME_F_METADATA_SUPPORTED |
2805 				  NVME_F_PCI_P2PDMA,
2806 	.reg_read32		= nvme_pci_reg_read32,
2807 	.reg_write32		= nvme_pci_reg_write32,
2808 	.reg_read64		= nvme_pci_reg_read64,
2809 	.free_ctrl		= nvme_pci_free_ctrl,
2810 	.submit_async_event	= nvme_pci_submit_async_event,
2811 	.get_address		= nvme_pci_get_address,
2812 };
2813 
2814 static int nvme_dev_map(struct nvme_dev *dev)
2815 {
2816 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2817 
2818 	if (pci_request_mem_regions(pdev, "nvme"))
2819 		return -ENODEV;
2820 
2821 	if (nvme_remap_bar(dev, NVME_REG_DBS + 4096))
2822 		goto release;
2823 
2824 	return 0;
2825   release:
2826 	pci_release_mem_regions(pdev);
2827 	return -ENODEV;
2828 }
2829 
2830 static unsigned long check_vendor_combination_bug(struct pci_dev *pdev)
2831 {
2832 	if (pdev->vendor == 0x144d && pdev->device == 0xa802) {
2833 		/*
2834 		 * Several Samsung devices seem to drop off the PCIe bus
2835 		 * randomly when APST is on and uses the deepest sleep state.
2836 		 * This has been observed on a Samsung "SM951 NVMe SAMSUNG
2837 		 * 256GB", a "PM951 NVMe SAMSUNG 512GB", and a "Samsung SSD
2838 		 * 950 PRO 256GB", but it seems to be restricted to two Dell
2839 		 * laptops.
2840 		 */
2841 		if (dmi_match(DMI_SYS_VENDOR, "Dell Inc.") &&
2842 		    (dmi_match(DMI_PRODUCT_NAME, "XPS 15 9550") ||
2843 		     dmi_match(DMI_PRODUCT_NAME, "Precision 5510")))
2844 			return NVME_QUIRK_NO_DEEPEST_PS;
2845 	} else if (pdev->vendor == 0x144d && pdev->device == 0xa804) {
2846 		/*
2847 		 * Samsung SSD 960 EVO drops off the PCIe bus after system
2848 		 * suspend on a Ryzen board, ASUS PRIME B350M-A, as well as
2849 		 * within few minutes after bootup on a Coffee Lake board -
2850 		 * ASUS PRIME Z370-A
2851 		 */
2852 		if (dmi_match(DMI_BOARD_VENDOR, "ASUSTeK COMPUTER INC.") &&
2853 		    (dmi_match(DMI_BOARD_NAME, "PRIME B350M-A") ||
2854 		     dmi_match(DMI_BOARD_NAME, "PRIME Z370-A")))
2855 			return NVME_QUIRK_NO_APST;
2856 	} else if ((pdev->vendor == 0x144d && (pdev->device == 0xa801 ||
2857 		    pdev->device == 0xa808 || pdev->device == 0xa809)) ||
2858 		   (pdev->vendor == 0x1e0f && pdev->device == 0x0001)) {
2859 		/*
2860 		 * Forcing to use host managed nvme power settings for
2861 		 * lowest idle power with quick resume latency on
2862 		 * Samsung and Toshiba SSDs based on suspend behavior
2863 		 * on Coffee Lake board for LENOVO C640
2864 		 */
2865 		if ((dmi_match(DMI_BOARD_VENDOR, "LENOVO")) &&
2866 		     dmi_match(DMI_BOARD_NAME, "LNVNB161216"))
2867 			return NVME_QUIRK_SIMPLE_SUSPEND;
2868 	}
2869 
2870 	return 0;
2871 }
2872 
2873 static void nvme_async_probe(void *data, async_cookie_t cookie)
2874 {
2875 	struct nvme_dev *dev = data;
2876 
2877 	flush_work(&dev->ctrl.reset_work);
2878 	flush_work(&dev->ctrl.scan_work);
2879 	nvme_put_ctrl(&dev->ctrl);
2880 }
2881 
2882 static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
2883 {
2884 	int node, result = -ENOMEM;
2885 	struct nvme_dev *dev;
2886 	unsigned long quirks = id->driver_data;
2887 	size_t alloc_size;
2888 
2889 	node = dev_to_node(&pdev->dev);
2890 	if (node == NUMA_NO_NODE)
2891 		set_dev_node(&pdev->dev, first_memory_node);
2892 
2893 	dev = kzalloc_node(sizeof(*dev), GFP_KERNEL, node);
2894 	if (!dev)
2895 		return -ENOMEM;
2896 
2897 	dev->nr_write_queues = write_queues;
2898 	dev->nr_poll_queues = poll_queues;
2899 	dev->nr_allocated_queues = nvme_max_io_queues(dev) + 1;
2900 	dev->queues = kcalloc_node(dev->nr_allocated_queues,
2901 			sizeof(struct nvme_queue), GFP_KERNEL, node);
2902 	if (!dev->queues)
2903 		goto free;
2904 
2905 	dev->dev = get_device(&pdev->dev);
2906 	pci_set_drvdata(pdev, dev);
2907 
2908 	result = nvme_dev_map(dev);
2909 	if (result)
2910 		goto put_pci;
2911 
2912 	INIT_WORK(&dev->ctrl.reset_work, nvme_reset_work);
2913 	INIT_WORK(&dev->remove_work, nvme_remove_dead_ctrl_work);
2914 	mutex_init(&dev->shutdown_lock);
2915 
2916 	result = nvme_setup_prp_pools(dev);
2917 	if (result)
2918 		goto unmap;
2919 
2920 	quirks |= check_vendor_combination_bug(pdev);
2921 
2922 	if (!noacpi && acpi_storage_d3(&pdev->dev)) {
2923 		/*
2924 		 * Some systems use a bios work around to ask for D3 on
2925 		 * platforms that support kernel managed suspend.
2926 		 */
2927 		dev_info(&pdev->dev,
2928 			 "platform quirk: setting simple suspend\n");
2929 		quirks |= NVME_QUIRK_SIMPLE_SUSPEND;
2930 	}
2931 
2932 	/*
2933 	 * Double check that our mempool alloc size will cover the biggest
2934 	 * command we support.
2935 	 */
2936 	alloc_size = nvme_pci_iod_alloc_size();
2937 	WARN_ON_ONCE(alloc_size > PAGE_SIZE);
2938 
2939 	dev->iod_mempool = mempool_create_node(1, mempool_kmalloc,
2940 						mempool_kfree,
2941 						(void *) alloc_size,
2942 						GFP_KERNEL, node);
2943 	if (!dev->iod_mempool) {
2944 		result = -ENOMEM;
2945 		goto release_pools;
2946 	}
2947 
2948 	result = nvme_init_ctrl(&dev->ctrl, &pdev->dev, &nvme_pci_ctrl_ops,
2949 			quirks);
2950 	if (result)
2951 		goto release_mempool;
2952 
2953 	dev_info(dev->ctrl.device, "pci function %s\n", dev_name(&pdev->dev));
2954 
2955 	nvme_reset_ctrl(&dev->ctrl);
2956 	async_schedule(nvme_async_probe, dev);
2957 
2958 	return 0;
2959 
2960  release_mempool:
2961 	mempool_destroy(dev->iod_mempool);
2962  release_pools:
2963 	nvme_release_prp_pools(dev);
2964  unmap:
2965 	nvme_dev_unmap(dev);
2966  put_pci:
2967 	put_device(dev->dev);
2968  free:
2969 	kfree(dev->queues);
2970 	kfree(dev);
2971 	return result;
2972 }
2973 
2974 static void nvme_reset_prepare(struct pci_dev *pdev)
2975 {
2976 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2977 
2978 	/*
2979 	 * We don't need to check the return value from waiting for the reset
2980 	 * state as pci_dev device lock is held, making it impossible to race
2981 	 * with ->remove().
2982 	 */
2983 	nvme_disable_prepare_reset(dev, false);
2984 	nvme_sync_queues(&dev->ctrl);
2985 }
2986 
2987 static void nvme_reset_done(struct pci_dev *pdev)
2988 {
2989 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2990 
2991 	if (!nvme_try_sched_reset(&dev->ctrl))
2992 		flush_work(&dev->ctrl.reset_work);
2993 }
2994 
2995 static void nvme_shutdown(struct pci_dev *pdev)
2996 {
2997 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2998 
2999 	nvme_disable_prepare_reset(dev, true);
3000 }
3001 
3002 /*
3003  * The driver's remove may be called on a device in a partially initialized
3004  * state. This function must not have any dependencies on the device state in
3005  * order to proceed.
3006  */
3007 static void nvme_remove(struct pci_dev *pdev)
3008 {
3009 	struct nvme_dev *dev = pci_get_drvdata(pdev);
3010 
3011 	nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DELETING);
3012 	pci_set_drvdata(pdev, NULL);
3013 
3014 	if (!pci_device_is_present(pdev)) {
3015 		nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DEAD);
3016 		nvme_dev_disable(dev, true);
3017 	}
3018 
3019 	flush_work(&dev->ctrl.reset_work);
3020 	nvme_stop_ctrl(&dev->ctrl);
3021 	nvme_remove_namespaces(&dev->ctrl);
3022 	nvme_dev_disable(dev, true);
3023 	nvme_release_cmb(dev);
3024 	nvme_free_host_mem(dev);
3025 	nvme_dev_remove_admin(dev);
3026 	nvme_free_queues(dev, 0);
3027 	nvme_release_prp_pools(dev);
3028 	nvme_dev_unmap(dev);
3029 	nvme_uninit_ctrl(&dev->ctrl);
3030 }
3031 
3032 #ifdef CONFIG_PM_SLEEP
3033 static int nvme_get_power_state(struct nvme_ctrl *ctrl, u32 *ps)
3034 {
3035 	return nvme_get_features(ctrl, NVME_FEAT_POWER_MGMT, 0, NULL, 0, ps);
3036 }
3037 
3038 static int nvme_set_power_state(struct nvme_ctrl *ctrl, u32 ps)
3039 {
3040 	return nvme_set_features(ctrl, NVME_FEAT_POWER_MGMT, ps, NULL, 0, NULL);
3041 }
3042 
3043 static int nvme_resume(struct device *dev)
3044 {
3045 	struct nvme_dev *ndev = pci_get_drvdata(to_pci_dev(dev));
3046 	struct nvme_ctrl *ctrl = &ndev->ctrl;
3047 
3048 	if (ndev->last_ps == U32_MAX ||
3049 	    nvme_set_power_state(ctrl, ndev->last_ps) != 0)
3050 		return nvme_try_sched_reset(&ndev->ctrl);
3051 	return 0;
3052 }
3053 
3054 static int nvme_suspend(struct device *dev)
3055 {
3056 	struct pci_dev *pdev = to_pci_dev(dev);
3057 	struct nvme_dev *ndev = pci_get_drvdata(pdev);
3058 	struct nvme_ctrl *ctrl = &ndev->ctrl;
3059 	int ret = -EBUSY;
3060 
3061 	ndev->last_ps = U32_MAX;
3062 
3063 	/*
3064 	 * The platform does not remove power for a kernel managed suspend so
3065 	 * use host managed nvme power settings for lowest idle power if
3066 	 * possible. This should have quicker resume latency than a full device
3067 	 * shutdown.  But if the firmware is involved after the suspend or the
3068 	 * device does not support any non-default power states, shut down the
3069 	 * device fully.
3070 	 *
3071 	 * If ASPM is not enabled for the device, shut down the device and allow
3072 	 * the PCI bus layer to put it into D3 in order to take the PCIe link
3073 	 * down, so as to allow the platform to achieve its minimum low-power
3074 	 * state (which may not be possible if the link is up).
3075 	 *
3076 	 * If a host memory buffer is enabled, shut down the device as the NVMe
3077 	 * specification allows the device to access the host memory buffer in
3078 	 * host DRAM from all power states, but hosts will fail access to DRAM
3079 	 * during S3.
3080 	 */
3081 	if (pm_suspend_via_firmware() || !ctrl->npss ||
3082 	    !pcie_aspm_enabled(pdev) ||
3083 	    ndev->nr_host_mem_descs ||
3084 	    (ndev->ctrl.quirks & NVME_QUIRK_SIMPLE_SUSPEND))
3085 		return nvme_disable_prepare_reset(ndev, true);
3086 
3087 	nvme_start_freeze(ctrl);
3088 	nvme_wait_freeze(ctrl);
3089 	nvme_sync_queues(ctrl);
3090 
3091 	if (ctrl->state != NVME_CTRL_LIVE)
3092 		goto unfreeze;
3093 
3094 	ret = nvme_get_power_state(ctrl, &ndev->last_ps);
3095 	if (ret < 0)
3096 		goto unfreeze;
3097 
3098 	/*
3099 	 * A saved state prevents pci pm from generically controlling the
3100 	 * device's power. If we're using protocol specific settings, we don't
3101 	 * want pci interfering.
3102 	 */
3103 	pci_save_state(pdev);
3104 
3105 	ret = nvme_set_power_state(ctrl, ctrl->npss);
3106 	if (ret < 0)
3107 		goto unfreeze;
3108 
3109 	if (ret) {
3110 		/* discard the saved state */
3111 		pci_load_saved_state(pdev, NULL);
3112 
3113 		/*
3114 		 * Clearing npss forces a controller reset on resume. The
3115 		 * correct value will be rediscovered then.
3116 		 */
3117 		ret = nvme_disable_prepare_reset(ndev, true);
3118 		ctrl->npss = 0;
3119 	}
3120 unfreeze:
3121 	nvme_unfreeze(ctrl);
3122 	return ret;
3123 }
3124 
3125 static int nvme_simple_suspend(struct device *dev)
3126 {
3127 	struct nvme_dev *ndev = pci_get_drvdata(to_pci_dev(dev));
3128 
3129 	return nvme_disable_prepare_reset(ndev, true);
3130 }
3131 
3132 static int nvme_simple_resume(struct device *dev)
3133 {
3134 	struct pci_dev *pdev = to_pci_dev(dev);
3135 	struct nvme_dev *ndev = pci_get_drvdata(pdev);
3136 
3137 	return nvme_try_sched_reset(&ndev->ctrl);
3138 }
3139 
3140 static const struct dev_pm_ops nvme_dev_pm_ops = {
3141 	.suspend	= nvme_suspend,
3142 	.resume		= nvme_resume,
3143 	.freeze		= nvme_simple_suspend,
3144 	.thaw		= nvme_simple_resume,
3145 	.poweroff	= nvme_simple_suspend,
3146 	.restore	= nvme_simple_resume,
3147 };
3148 #endif /* CONFIG_PM_SLEEP */
3149 
3150 static pci_ers_result_t nvme_error_detected(struct pci_dev *pdev,
3151 						pci_channel_state_t state)
3152 {
3153 	struct nvme_dev *dev = pci_get_drvdata(pdev);
3154 
3155 	/*
3156 	 * A frozen channel requires a reset. When detected, this method will
3157 	 * shutdown the controller to quiesce. The controller will be restarted
3158 	 * after the slot reset through driver's slot_reset callback.
3159 	 */
3160 	switch (state) {
3161 	case pci_channel_io_normal:
3162 		return PCI_ERS_RESULT_CAN_RECOVER;
3163 	case pci_channel_io_frozen:
3164 		dev_warn(dev->ctrl.device,
3165 			"frozen state error detected, reset controller\n");
3166 		nvme_dev_disable(dev, false);
3167 		return PCI_ERS_RESULT_NEED_RESET;
3168 	case pci_channel_io_perm_failure:
3169 		dev_warn(dev->ctrl.device,
3170 			"failure state error detected, request disconnect\n");
3171 		return PCI_ERS_RESULT_DISCONNECT;
3172 	}
3173 	return PCI_ERS_RESULT_NEED_RESET;
3174 }
3175 
3176 static pci_ers_result_t nvme_slot_reset(struct pci_dev *pdev)
3177 {
3178 	struct nvme_dev *dev = pci_get_drvdata(pdev);
3179 
3180 	dev_info(dev->ctrl.device, "restart after slot reset\n");
3181 	pci_restore_state(pdev);
3182 	nvme_reset_ctrl(&dev->ctrl);
3183 	return PCI_ERS_RESULT_RECOVERED;
3184 }
3185 
3186 static void nvme_error_resume(struct pci_dev *pdev)
3187 {
3188 	struct nvme_dev *dev = pci_get_drvdata(pdev);
3189 
3190 	flush_work(&dev->ctrl.reset_work);
3191 }
3192 
3193 static const struct pci_error_handlers nvme_err_handler = {
3194 	.error_detected	= nvme_error_detected,
3195 	.slot_reset	= nvme_slot_reset,
3196 	.resume		= nvme_error_resume,
3197 	.reset_prepare	= nvme_reset_prepare,
3198 	.reset_done	= nvme_reset_done,
3199 };
3200 
3201 static const struct pci_device_id nvme_id_table[] = {
3202 	{ PCI_VDEVICE(INTEL, 0x0953),	/* Intel 750/P3500/P3600/P3700 */
3203 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
3204 				NVME_QUIRK_DEALLOCATE_ZEROES, },
3205 	{ PCI_VDEVICE(INTEL, 0x0a53),	/* Intel P3520 */
3206 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
3207 				NVME_QUIRK_DEALLOCATE_ZEROES, },
3208 	{ PCI_VDEVICE(INTEL, 0x0a54),	/* Intel P4500/P4600 */
3209 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
3210 				NVME_QUIRK_DEALLOCATE_ZEROES, },
3211 	{ PCI_VDEVICE(INTEL, 0x0a55),	/* Dell Express Flash P4600 */
3212 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
3213 				NVME_QUIRK_DEALLOCATE_ZEROES, },
3214 	{ PCI_VDEVICE(INTEL, 0xf1a5),	/* Intel 600P/P3100 */
3215 		.driver_data = NVME_QUIRK_NO_DEEPEST_PS |
3216 				NVME_QUIRK_MEDIUM_PRIO_SQ |
3217 				NVME_QUIRK_NO_TEMP_THRESH_CHANGE |
3218 				NVME_QUIRK_DISABLE_WRITE_ZEROES, },
3219 	{ PCI_VDEVICE(INTEL, 0xf1a6),	/* Intel 760p/Pro 7600p */
3220 		.driver_data = NVME_QUIRK_IGNORE_DEV_SUBNQN, },
3221 	{ PCI_VDEVICE(INTEL, 0x5845),	/* Qemu emulated controller */
3222 		.driver_data = NVME_QUIRK_IDENTIFY_CNS |
3223 				NVME_QUIRK_DISABLE_WRITE_ZEROES, },
3224 	{ PCI_DEVICE(0x126f, 0x2263),	/* Silicon Motion unidentified */
3225 		.driver_data = NVME_QUIRK_NO_NS_DESC_LIST, },
3226 	{ PCI_DEVICE(0x1bb1, 0x0100),   /* Seagate Nytro Flash Storage */
3227 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY |
3228 				NVME_QUIRK_NO_NS_DESC_LIST, },
3229 	{ PCI_DEVICE(0x1c58, 0x0003),	/* HGST adapter */
3230 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
3231 	{ PCI_DEVICE(0x1c58, 0x0023),	/* WDC SN200 adapter */
3232 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
3233 	{ PCI_DEVICE(0x1c5f, 0x0540),	/* Memblaze Pblaze4 adapter */
3234 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
3235 	{ PCI_DEVICE(0x144d, 0xa821),   /* Samsung PM1725 */
3236 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
3237 	{ PCI_DEVICE(0x144d, 0xa822),   /* Samsung PM1725a */
3238 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY |
3239 				NVME_QUIRK_DISABLE_WRITE_ZEROES|
3240 				NVME_QUIRK_IGNORE_DEV_SUBNQN, },
3241 	{ PCI_DEVICE(0x1987, 0x5016),	/* Phison E16 */
3242 		.driver_data = NVME_QUIRK_IGNORE_DEV_SUBNQN, },
3243 	{ PCI_DEVICE(0x1b4b, 0x1092),	/* Lexar 256 GB SSD */
3244 		.driver_data = NVME_QUIRK_NO_NS_DESC_LIST |
3245 				NVME_QUIRK_IGNORE_DEV_SUBNQN, },
3246 	{ PCI_DEVICE(0x1d1d, 0x1f1f),	/* LighNVM qemu device */
3247 		.driver_data = NVME_QUIRK_LIGHTNVM, },
3248 	{ PCI_DEVICE(0x1d1d, 0x2807),	/* CNEX WL */
3249 		.driver_data = NVME_QUIRK_LIGHTNVM, },
3250 	{ PCI_DEVICE(0x1d1d, 0x2601),	/* CNEX Granby */
3251 		.driver_data = NVME_QUIRK_LIGHTNVM, },
3252 	{ PCI_DEVICE(0x10ec, 0x5762),   /* ADATA SX6000LNP */
3253 		.driver_data = NVME_QUIRK_IGNORE_DEV_SUBNQN, },
3254 	{ PCI_DEVICE(0x1cc1, 0x8201),   /* ADATA SX8200PNP 512GB */
3255 		.driver_data = NVME_QUIRK_NO_DEEPEST_PS |
3256 				NVME_QUIRK_IGNORE_DEV_SUBNQN, },
3257 	{ PCI_DEVICE(0x1c5c, 0x1504),   /* SK Hynix PC400 */
3258 		.driver_data = NVME_QUIRK_DISABLE_WRITE_ZEROES, },
3259 	{ PCI_DEVICE(0x15b7, 0x2001),   /*  Sandisk Skyhawk */
3260 		.driver_data = NVME_QUIRK_DISABLE_WRITE_ZEROES, },
3261 	{ PCI_DEVICE(0x1d97, 0x2263),   /* SPCC */
3262 		.driver_data = NVME_QUIRK_DISABLE_WRITE_ZEROES, },
3263 	{ PCI_DEVICE(0x2646, 0x2262),   /* KINGSTON SKC2000 NVMe SSD */
3264 		.driver_data = NVME_QUIRK_NO_DEEPEST_PS, },
3265 	{ PCI_DEVICE(0x2646, 0x2263),   /* KINGSTON A2000 NVMe SSD  */
3266 		.driver_data = NVME_QUIRK_NO_DEEPEST_PS, },
3267 	{ PCI_DEVICE(PCI_VENDOR_ID_AMAZON, 0x0061),
3268 		.driver_data = NVME_QUIRK_DMA_ADDRESS_BITS_48, },
3269 	{ PCI_DEVICE(PCI_VENDOR_ID_AMAZON, 0x0065),
3270 		.driver_data = NVME_QUIRK_DMA_ADDRESS_BITS_48, },
3271 	{ PCI_DEVICE(PCI_VENDOR_ID_AMAZON, 0x8061),
3272 		.driver_data = NVME_QUIRK_DMA_ADDRESS_BITS_48, },
3273 	{ PCI_DEVICE(PCI_VENDOR_ID_AMAZON, 0xcd00),
3274 		.driver_data = NVME_QUIRK_DMA_ADDRESS_BITS_48, },
3275 	{ PCI_DEVICE(PCI_VENDOR_ID_AMAZON, 0xcd01),
3276 		.driver_data = NVME_QUIRK_DMA_ADDRESS_BITS_48, },
3277 	{ PCI_DEVICE(PCI_VENDOR_ID_AMAZON, 0xcd02),
3278 		.driver_data = NVME_QUIRK_DMA_ADDRESS_BITS_48, },
3279 	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2001),
3280 		.driver_data = NVME_QUIRK_SINGLE_VECTOR },
3281 	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2003) },
3282 	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2005),
3283 		.driver_data = NVME_QUIRK_SINGLE_VECTOR |
3284 				NVME_QUIRK_128_BYTES_SQES |
3285 				NVME_QUIRK_SHARED_TAGS },
3286 
3287 	{ PCI_DEVICE_CLASS(PCI_CLASS_STORAGE_EXPRESS, 0xffffff) },
3288 	{ 0, }
3289 };
3290 MODULE_DEVICE_TABLE(pci, nvme_id_table);
3291 
3292 static struct pci_driver nvme_driver = {
3293 	.name		= "nvme",
3294 	.id_table	= nvme_id_table,
3295 	.probe		= nvme_probe,
3296 	.remove		= nvme_remove,
3297 	.shutdown	= nvme_shutdown,
3298 #ifdef CONFIG_PM_SLEEP
3299 	.driver		= {
3300 		.pm	= &nvme_dev_pm_ops,
3301 	},
3302 #endif
3303 	.sriov_configure = pci_sriov_configure_simple,
3304 	.err_handler	= &nvme_err_handler,
3305 };
3306 
3307 static int __init nvme_init(void)
3308 {
3309 	BUILD_BUG_ON(sizeof(struct nvme_create_cq) != 64);
3310 	BUILD_BUG_ON(sizeof(struct nvme_create_sq) != 64);
3311 	BUILD_BUG_ON(sizeof(struct nvme_delete_queue) != 64);
3312 	BUILD_BUG_ON(IRQ_AFFINITY_MAX_SETS < 2);
3313 
3314 	return pci_register_driver(&nvme_driver);
3315 }
3316 
3317 static void __exit nvme_exit(void)
3318 {
3319 	pci_unregister_driver(&nvme_driver);
3320 	flush_workqueue(nvme_wq);
3321 }
3322 
3323 MODULE_AUTHOR("Matthew Wilcox <willy@linux.intel.com>");
3324 MODULE_LICENSE("GPL");
3325 MODULE_VERSION("1.0");
3326 module_init(nvme_init);
3327 module_exit(nvme_exit);
3328