xref: /linux/drivers/nvme/host/pci.c (revision 6a61b70b43c9c4cbc7314bf6c8b5ba8b0d6e1e7b)
1 /*
2  * NVM Express device driver
3  * Copyright (c) 2011-2014, Intel Corporation.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms and conditions of the GNU General Public License,
7  * version 2, as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  */
14 
15 #include <linux/aer.h>
16 #include <linux/async.h>
17 #include <linux/blkdev.h>
18 #include <linux/blk-mq.h>
19 #include <linux/blk-mq-pci.h>
20 #include <linux/dmi.h>
21 #include <linux/init.h>
22 #include <linux/interrupt.h>
23 #include <linux/io.h>
24 #include <linux/mm.h>
25 #include <linux/module.h>
26 #include <linux/mutex.h>
27 #include <linux/once.h>
28 #include <linux/pci.h>
29 #include <linux/t10-pi.h>
30 #include <linux/types.h>
31 #include <linux/io-64-nonatomic-lo-hi.h>
32 #include <linux/sed-opal.h>
33 
34 #include "nvme.h"
35 
36 #define SQ_SIZE(depth)		(depth * sizeof(struct nvme_command))
37 #define CQ_SIZE(depth)		(depth * sizeof(struct nvme_completion))
38 
39 #define SGES_PER_PAGE	(PAGE_SIZE / sizeof(struct nvme_sgl_desc))
40 
41 static int use_threaded_interrupts;
42 module_param(use_threaded_interrupts, int, 0);
43 
44 static bool use_cmb_sqes = true;
45 module_param(use_cmb_sqes, bool, 0644);
46 MODULE_PARM_DESC(use_cmb_sqes, "use controller's memory buffer for I/O SQes");
47 
48 static unsigned int max_host_mem_size_mb = 128;
49 module_param(max_host_mem_size_mb, uint, 0444);
50 MODULE_PARM_DESC(max_host_mem_size_mb,
51 	"Maximum Host Memory Buffer (HMB) size per controller (in MiB)");
52 
53 static unsigned int sgl_threshold = SZ_32K;
54 module_param(sgl_threshold, uint, 0644);
55 MODULE_PARM_DESC(sgl_threshold,
56 		"Use SGLs when average request segment size is larger or equal to "
57 		"this size. Use 0 to disable SGLs.");
58 
59 static int io_queue_depth_set(const char *val, const struct kernel_param *kp);
60 static const struct kernel_param_ops io_queue_depth_ops = {
61 	.set = io_queue_depth_set,
62 	.get = param_get_int,
63 };
64 
65 static int io_queue_depth = 1024;
66 module_param_cb(io_queue_depth, &io_queue_depth_ops, &io_queue_depth, 0644);
67 MODULE_PARM_DESC(io_queue_depth, "set io queue depth, should >= 2");
68 
69 struct nvme_dev;
70 struct nvme_queue;
71 
72 static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown);
73 
74 /*
75  * Represents an NVM Express device.  Each nvme_dev is a PCI function.
76  */
77 struct nvme_dev {
78 	struct nvme_queue *queues;
79 	struct blk_mq_tag_set tagset;
80 	struct blk_mq_tag_set admin_tagset;
81 	u32 __iomem *dbs;
82 	struct device *dev;
83 	struct dma_pool *prp_page_pool;
84 	struct dma_pool *prp_small_pool;
85 	unsigned online_queues;
86 	unsigned max_qid;
87 	unsigned int num_vecs;
88 	int q_depth;
89 	u32 db_stride;
90 	void __iomem *bar;
91 	unsigned long bar_mapped_size;
92 	struct work_struct remove_work;
93 	struct mutex shutdown_lock;
94 	bool subsystem;
95 	void __iomem *cmb;
96 	pci_bus_addr_t cmb_bus_addr;
97 	u64 cmb_size;
98 	u32 cmbsz;
99 	u32 cmbloc;
100 	struct nvme_ctrl ctrl;
101 	struct completion ioq_wait;
102 
103 	/* shadow doorbell buffer support: */
104 	u32 *dbbuf_dbs;
105 	dma_addr_t dbbuf_dbs_dma_addr;
106 	u32 *dbbuf_eis;
107 	dma_addr_t dbbuf_eis_dma_addr;
108 
109 	/* host memory buffer support: */
110 	u64 host_mem_size;
111 	u32 nr_host_mem_descs;
112 	dma_addr_t host_mem_descs_dma;
113 	struct nvme_host_mem_buf_desc *host_mem_descs;
114 	void **host_mem_desc_bufs;
115 };
116 
117 static int io_queue_depth_set(const char *val, const struct kernel_param *kp)
118 {
119 	int n = 0, ret;
120 
121 	ret = kstrtoint(val, 10, &n);
122 	if (ret != 0 || n < 2)
123 		return -EINVAL;
124 
125 	return param_set_int(val, kp);
126 }
127 
128 static inline unsigned int sq_idx(unsigned int qid, u32 stride)
129 {
130 	return qid * 2 * stride;
131 }
132 
133 static inline unsigned int cq_idx(unsigned int qid, u32 stride)
134 {
135 	return (qid * 2 + 1) * stride;
136 }
137 
138 static inline struct nvme_dev *to_nvme_dev(struct nvme_ctrl *ctrl)
139 {
140 	return container_of(ctrl, struct nvme_dev, ctrl);
141 }
142 
143 /*
144  * An NVM Express queue.  Each device has at least two (one for admin
145  * commands and one for I/O commands).
146  */
147 struct nvme_queue {
148 	struct device *q_dmadev;
149 	struct nvme_dev *dev;
150 	spinlock_t sq_lock;
151 	struct nvme_command *sq_cmds;
152 	struct nvme_command __iomem *sq_cmds_io;
153 	spinlock_t cq_lock ____cacheline_aligned_in_smp;
154 	volatile struct nvme_completion *cqes;
155 	struct blk_mq_tags **tags;
156 	dma_addr_t sq_dma_addr;
157 	dma_addr_t cq_dma_addr;
158 	u32 __iomem *q_db;
159 	u16 q_depth;
160 	s16 cq_vector;
161 	u16 sq_tail;
162 	u16 cq_head;
163 	u16 last_cq_head;
164 	u16 qid;
165 	u8 cq_phase;
166 	u32 *dbbuf_sq_db;
167 	u32 *dbbuf_cq_db;
168 	u32 *dbbuf_sq_ei;
169 	u32 *dbbuf_cq_ei;
170 };
171 
172 /*
173  * The nvme_iod describes the data in an I/O, including the list of PRP
174  * entries.  You can't see it in this data structure because C doesn't let
175  * me express that.  Use nvme_init_iod to ensure there's enough space
176  * allocated to store the PRP list.
177  */
178 struct nvme_iod {
179 	struct nvme_request req;
180 	struct nvme_queue *nvmeq;
181 	bool use_sgl;
182 	int aborted;
183 	int npages;		/* In the PRP list. 0 means small pool in use */
184 	int nents;		/* Used in scatterlist */
185 	int length;		/* Of data, in bytes */
186 	dma_addr_t first_dma;
187 	struct scatterlist meta_sg; /* metadata requires single contiguous buffer */
188 	struct scatterlist *sg;
189 	struct scatterlist inline_sg[0];
190 };
191 
192 /*
193  * Check we didin't inadvertently grow the command struct
194  */
195 static inline void _nvme_check_size(void)
196 {
197 	BUILD_BUG_ON(sizeof(struct nvme_rw_command) != 64);
198 	BUILD_BUG_ON(sizeof(struct nvme_create_cq) != 64);
199 	BUILD_BUG_ON(sizeof(struct nvme_create_sq) != 64);
200 	BUILD_BUG_ON(sizeof(struct nvme_delete_queue) != 64);
201 	BUILD_BUG_ON(sizeof(struct nvme_features) != 64);
202 	BUILD_BUG_ON(sizeof(struct nvme_format_cmd) != 64);
203 	BUILD_BUG_ON(sizeof(struct nvme_abort_cmd) != 64);
204 	BUILD_BUG_ON(sizeof(struct nvme_command) != 64);
205 	BUILD_BUG_ON(sizeof(struct nvme_id_ctrl) != NVME_IDENTIFY_DATA_SIZE);
206 	BUILD_BUG_ON(sizeof(struct nvme_id_ns) != NVME_IDENTIFY_DATA_SIZE);
207 	BUILD_BUG_ON(sizeof(struct nvme_lba_range_type) != 64);
208 	BUILD_BUG_ON(sizeof(struct nvme_smart_log) != 512);
209 	BUILD_BUG_ON(sizeof(struct nvme_dbbuf) != 64);
210 }
211 
212 static inline unsigned int nvme_dbbuf_size(u32 stride)
213 {
214 	return ((num_possible_cpus() + 1) * 8 * stride);
215 }
216 
217 static int nvme_dbbuf_dma_alloc(struct nvme_dev *dev)
218 {
219 	unsigned int mem_size = nvme_dbbuf_size(dev->db_stride);
220 
221 	if (dev->dbbuf_dbs)
222 		return 0;
223 
224 	dev->dbbuf_dbs = dma_alloc_coherent(dev->dev, mem_size,
225 					    &dev->dbbuf_dbs_dma_addr,
226 					    GFP_KERNEL);
227 	if (!dev->dbbuf_dbs)
228 		return -ENOMEM;
229 	dev->dbbuf_eis = dma_alloc_coherent(dev->dev, mem_size,
230 					    &dev->dbbuf_eis_dma_addr,
231 					    GFP_KERNEL);
232 	if (!dev->dbbuf_eis) {
233 		dma_free_coherent(dev->dev, mem_size,
234 				  dev->dbbuf_dbs, dev->dbbuf_dbs_dma_addr);
235 		dev->dbbuf_dbs = NULL;
236 		return -ENOMEM;
237 	}
238 
239 	return 0;
240 }
241 
242 static void nvme_dbbuf_dma_free(struct nvme_dev *dev)
243 {
244 	unsigned int mem_size = nvme_dbbuf_size(dev->db_stride);
245 
246 	if (dev->dbbuf_dbs) {
247 		dma_free_coherent(dev->dev, mem_size,
248 				  dev->dbbuf_dbs, dev->dbbuf_dbs_dma_addr);
249 		dev->dbbuf_dbs = NULL;
250 	}
251 	if (dev->dbbuf_eis) {
252 		dma_free_coherent(dev->dev, mem_size,
253 				  dev->dbbuf_eis, dev->dbbuf_eis_dma_addr);
254 		dev->dbbuf_eis = NULL;
255 	}
256 }
257 
258 static void nvme_dbbuf_init(struct nvme_dev *dev,
259 			    struct nvme_queue *nvmeq, int qid)
260 {
261 	if (!dev->dbbuf_dbs || !qid)
262 		return;
263 
264 	nvmeq->dbbuf_sq_db = &dev->dbbuf_dbs[sq_idx(qid, dev->db_stride)];
265 	nvmeq->dbbuf_cq_db = &dev->dbbuf_dbs[cq_idx(qid, dev->db_stride)];
266 	nvmeq->dbbuf_sq_ei = &dev->dbbuf_eis[sq_idx(qid, dev->db_stride)];
267 	nvmeq->dbbuf_cq_ei = &dev->dbbuf_eis[cq_idx(qid, dev->db_stride)];
268 }
269 
270 static void nvme_dbbuf_set(struct nvme_dev *dev)
271 {
272 	struct nvme_command c;
273 
274 	if (!dev->dbbuf_dbs)
275 		return;
276 
277 	memset(&c, 0, sizeof(c));
278 	c.dbbuf.opcode = nvme_admin_dbbuf;
279 	c.dbbuf.prp1 = cpu_to_le64(dev->dbbuf_dbs_dma_addr);
280 	c.dbbuf.prp2 = cpu_to_le64(dev->dbbuf_eis_dma_addr);
281 
282 	if (nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0)) {
283 		dev_warn(dev->ctrl.device, "unable to set dbbuf\n");
284 		/* Free memory and continue on */
285 		nvme_dbbuf_dma_free(dev);
286 	}
287 }
288 
289 static inline int nvme_dbbuf_need_event(u16 event_idx, u16 new_idx, u16 old)
290 {
291 	return (u16)(new_idx - event_idx - 1) < (u16)(new_idx - old);
292 }
293 
294 /* Update dbbuf and return true if an MMIO is required */
295 static bool nvme_dbbuf_update_and_check_event(u16 value, u32 *dbbuf_db,
296 					      volatile u32 *dbbuf_ei)
297 {
298 	if (dbbuf_db) {
299 		u16 old_value;
300 
301 		/*
302 		 * Ensure that the queue is written before updating
303 		 * the doorbell in memory
304 		 */
305 		wmb();
306 
307 		old_value = *dbbuf_db;
308 		*dbbuf_db = value;
309 
310 		if (!nvme_dbbuf_need_event(*dbbuf_ei, value, old_value))
311 			return false;
312 	}
313 
314 	return true;
315 }
316 
317 /*
318  * Max size of iod being embedded in the request payload
319  */
320 #define NVME_INT_PAGES		2
321 #define NVME_INT_BYTES(dev)	(NVME_INT_PAGES * (dev)->ctrl.page_size)
322 
323 /*
324  * Will slightly overestimate the number of pages needed.  This is OK
325  * as it only leads to a small amount of wasted memory for the lifetime of
326  * the I/O.
327  */
328 static int nvme_npages(unsigned size, struct nvme_dev *dev)
329 {
330 	unsigned nprps = DIV_ROUND_UP(size + dev->ctrl.page_size,
331 				      dev->ctrl.page_size);
332 	return DIV_ROUND_UP(8 * nprps, PAGE_SIZE - 8);
333 }
334 
335 /*
336  * Calculates the number of pages needed for the SGL segments. For example a 4k
337  * page can accommodate 256 SGL descriptors.
338  */
339 static int nvme_pci_npages_sgl(unsigned int num_seg)
340 {
341 	return DIV_ROUND_UP(num_seg * sizeof(struct nvme_sgl_desc), PAGE_SIZE);
342 }
343 
344 static unsigned int nvme_pci_iod_alloc_size(struct nvme_dev *dev,
345 		unsigned int size, unsigned int nseg, bool use_sgl)
346 {
347 	size_t alloc_size;
348 
349 	if (use_sgl)
350 		alloc_size = sizeof(__le64 *) * nvme_pci_npages_sgl(nseg);
351 	else
352 		alloc_size = sizeof(__le64 *) * nvme_npages(size, dev);
353 
354 	return alloc_size + sizeof(struct scatterlist) * nseg;
355 }
356 
357 static unsigned int nvme_pci_cmd_size(struct nvme_dev *dev, bool use_sgl)
358 {
359 	unsigned int alloc_size = nvme_pci_iod_alloc_size(dev,
360 				    NVME_INT_BYTES(dev), NVME_INT_PAGES,
361 				    use_sgl);
362 
363 	return sizeof(struct nvme_iod) + alloc_size;
364 }
365 
366 static int nvme_admin_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
367 				unsigned int hctx_idx)
368 {
369 	struct nvme_dev *dev = data;
370 	struct nvme_queue *nvmeq = &dev->queues[0];
371 
372 	WARN_ON(hctx_idx != 0);
373 	WARN_ON(dev->admin_tagset.tags[0] != hctx->tags);
374 	WARN_ON(nvmeq->tags);
375 
376 	hctx->driver_data = nvmeq;
377 	nvmeq->tags = &dev->admin_tagset.tags[0];
378 	return 0;
379 }
380 
381 static void nvme_admin_exit_hctx(struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx)
382 {
383 	struct nvme_queue *nvmeq = hctx->driver_data;
384 
385 	nvmeq->tags = NULL;
386 }
387 
388 static int nvme_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
389 			  unsigned int hctx_idx)
390 {
391 	struct nvme_dev *dev = data;
392 	struct nvme_queue *nvmeq = &dev->queues[hctx_idx + 1];
393 
394 	if (!nvmeq->tags)
395 		nvmeq->tags = &dev->tagset.tags[hctx_idx];
396 
397 	WARN_ON(dev->tagset.tags[hctx_idx] != hctx->tags);
398 	hctx->driver_data = nvmeq;
399 	return 0;
400 }
401 
402 static int nvme_init_request(struct blk_mq_tag_set *set, struct request *req,
403 		unsigned int hctx_idx, unsigned int numa_node)
404 {
405 	struct nvme_dev *dev = set->driver_data;
406 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
407 	int queue_idx = (set == &dev->tagset) ? hctx_idx + 1 : 0;
408 	struct nvme_queue *nvmeq = &dev->queues[queue_idx];
409 
410 	BUG_ON(!nvmeq);
411 	iod->nvmeq = nvmeq;
412 	return 0;
413 }
414 
415 static int nvme_pci_map_queues(struct blk_mq_tag_set *set)
416 {
417 	struct nvme_dev *dev = set->driver_data;
418 
419 	return blk_mq_pci_map_queues(set, to_pci_dev(dev->dev),
420 			dev->num_vecs > 1 ? 1 /* admin queue */ : 0);
421 }
422 
423 /**
424  * nvme_submit_cmd() - Copy a command into a queue and ring the doorbell
425  * @nvmeq: The queue to use
426  * @cmd: The command to send
427  */
428 static void nvme_submit_cmd(struct nvme_queue *nvmeq, struct nvme_command *cmd)
429 {
430 	spin_lock(&nvmeq->sq_lock);
431 	if (nvmeq->sq_cmds_io)
432 		memcpy_toio(&nvmeq->sq_cmds_io[nvmeq->sq_tail], cmd,
433 				sizeof(*cmd));
434 	else
435 		memcpy(&nvmeq->sq_cmds[nvmeq->sq_tail], cmd, sizeof(*cmd));
436 
437 	if (++nvmeq->sq_tail == nvmeq->q_depth)
438 		nvmeq->sq_tail = 0;
439 	if (nvme_dbbuf_update_and_check_event(nvmeq->sq_tail,
440 			nvmeq->dbbuf_sq_db, nvmeq->dbbuf_sq_ei))
441 		writel(nvmeq->sq_tail, nvmeq->q_db);
442 	spin_unlock(&nvmeq->sq_lock);
443 }
444 
445 static void **nvme_pci_iod_list(struct request *req)
446 {
447 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
448 	return (void **)(iod->sg + blk_rq_nr_phys_segments(req));
449 }
450 
451 static inline bool nvme_pci_use_sgls(struct nvme_dev *dev, struct request *req)
452 {
453 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
454 	int nseg = blk_rq_nr_phys_segments(req);
455 	unsigned int avg_seg_size;
456 
457 	if (nseg == 0)
458 		return false;
459 
460 	avg_seg_size = DIV_ROUND_UP(blk_rq_payload_bytes(req), nseg);
461 
462 	if (!(dev->ctrl.sgls & ((1 << 0) | (1 << 1))))
463 		return false;
464 	if (!iod->nvmeq->qid)
465 		return false;
466 	if (!sgl_threshold || avg_seg_size < sgl_threshold)
467 		return false;
468 	return true;
469 }
470 
471 static blk_status_t nvme_init_iod(struct request *rq, struct nvme_dev *dev)
472 {
473 	struct nvme_iod *iod = blk_mq_rq_to_pdu(rq);
474 	int nseg = blk_rq_nr_phys_segments(rq);
475 	unsigned int size = blk_rq_payload_bytes(rq);
476 
477 	iod->use_sgl = nvme_pci_use_sgls(dev, rq);
478 
479 	if (nseg > NVME_INT_PAGES || size > NVME_INT_BYTES(dev)) {
480 		size_t alloc_size = nvme_pci_iod_alloc_size(dev, size, nseg,
481 				iod->use_sgl);
482 
483 		iod->sg = kmalloc(alloc_size, GFP_ATOMIC);
484 		if (!iod->sg)
485 			return BLK_STS_RESOURCE;
486 	} else {
487 		iod->sg = iod->inline_sg;
488 	}
489 
490 	iod->aborted = 0;
491 	iod->npages = -1;
492 	iod->nents = 0;
493 	iod->length = size;
494 
495 	return BLK_STS_OK;
496 }
497 
498 static void nvme_free_iod(struct nvme_dev *dev, struct request *req)
499 {
500 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
501 	const int last_prp = dev->ctrl.page_size / sizeof(__le64) - 1;
502 	dma_addr_t dma_addr = iod->first_dma, next_dma_addr;
503 
504 	int i;
505 
506 	if (iod->npages == 0)
507 		dma_pool_free(dev->prp_small_pool, nvme_pci_iod_list(req)[0],
508 			dma_addr);
509 
510 	for (i = 0; i < iod->npages; i++) {
511 		void *addr = nvme_pci_iod_list(req)[i];
512 
513 		if (iod->use_sgl) {
514 			struct nvme_sgl_desc *sg_list = addr;
515 
516 			next_dma_addr =
517 			    le64_to_cpu((sg_list[SGES_PER_PAGE - 1]).addr);
518 		} else {
519 			__le64 *prp_list = addr;
520 
521 			next_dma_addr = le64_to_cpu(prp_list[last_prp]);
522 		}
523 
524 		dma_pool_free(dev->prp_page_pool, addr, dma_addr);
525 		dma_addr = next_dma_addr;
526 	}
527 
528 	if (iod->sg != iod->inline_sg)
529 		kfree(iod->sg);
530 }
531 
532 #ifdef CONFIG_BLK_DEV_INTEGRITY
533 static void nvme_dif_prep(u32 p, u32 v, struct t10_pi_tuple *pi)
534 {
535 	if (be32_to_cpu(pi->ref_tag) == v)
536 		pi->ref_tag = cpu_to_be32(p);
537 }
538 
539 static void nvme_dif_complete(u32 p, u32 v, struct t10_pi_tuple *pi)
540 {
541 	if (be32_to_cpu(pi->ref_tag) == p)
542 		pi->ref_tag = cpu_to_be32(v);
543 }
544 
545 /**
546  * nvme_dif_remap - remaps ref tags to bip seed and physical lba
547  *
548  * The virtual start sector is the one that was originally submitted by the
549  * block layer.	Due to partitioning, MD/DM cloning, etc. the actual physical
550  * start sector may be different. Remap protection information to match the
551  * physical LBA on writes, and back to the original seed on reads.
552  *
553  * Type 0 and 3 do not have a ref tag, so no remapping required.
554  */
555 static void nvme_dif_remap(struct request *req,
556 			void (*dif_swap)(u32 p, u32 v, struct t10_pi_tuple *pi))
557 {
558 	struct nvme_ns *ns = req->rq_disk->private_data;
559 	struct bio_integrity_payload *bip;
560 	struct t10_pi_tuple *pi;
561 	void *p, *pmap;
562 	u32 i, nlb, ts, phys, virt;
563 
564 	if (!ns->pi_type || ns->pi_type == NVME_NS_DPS_PI_TYPE3)
565 		return;
566 
567 	bip = bio_integrity(req->bio);
568 	if (!bip)
569 		return;
570 
571 	pmap = kmap_atomic(bip->bip_vec->bv_page) + bip->bip_vec->bv_offset;
572 
573 	p = pmap;
574 	virt = bip_get_seed(bip);
575 	phys = nvme_block_nr(ns, blk_rq_pos(req));
576 	nlb = (blk_rq_bytes(req) >> ns->lba_shift);
577 	ts = ns->disk->queue->integrity.tuple_size;
578 
579 	for (i = 0; i < nlb; i++, virt++, phys++) {
580 		pi = (struct t10_pi_tuple *)p;
581 		dif_swap(phys, virt, pi);
582 		p += ts;
583 	}
584 	kunmap_atomic(pmap);
585 }
586 #else /* CONFIG_BLK_DEV_INTEGRITY */
587 static void nvme_dif_remap(struct request *req,
588 			void (*dif_swap)(u32 p, u32 v, struct t10_pi_tuple *pi))
589 {
590 }
591 static void nvme_dif_prep(u32 p, u32 v, struct t10_pi_tuple *pi)
592 {
593 }
594 static void nvme_dif_complete(u32 p, u32 v, struct t10_pi_tuple *pi)
595 {
596 }
597 #endif
598 
599 static void nvme_print_sgl(struct scatterlist *sgl, int nents)
600 {
601 	int i;
602 	struct scatterlist *sg;
603 
604 	for_each_sg(sgl, sg, nents, i) {
605 		dma_addr_t phys = sg_phys(sg);
606 		pr_warn("sg[%d] phys_addr:%pad offset:%d length:%d "
607 			"dma_address:%pad dma_length:%d\n",
608 			i, &phys, sg->offset, sg->length, &sg_dma_address(sg),
609 			sg_dma_len(sg));
610 	}
611 }
612 
613 static blk_status_t nvme_pci_setup_prps(struct nvme_dev *dev,
614 		struct request *req, struct nvme_rw_command *cmnd)
615 {
616 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
617 	struct dma_pool *pool;
618 	int length = blk_rq_payload_bytes(req);
619 	struct scatterlist *sg = iod->sg;
620 	int dma_len = sg_dma_len(sg);
621 	u64 dma_addr = sg_dma_address(sg);
622 	u32 page_size = dev->ctrl.page_size;
623 	int offset = dma_addr & (page_size - 1);
624 	__le64 *prp_list;
625 	void **list = nvme_pci_iod_list(req);
626 	dma_addr_t prp_dma;
627 	int nprps, i;
628 
629 	length -= (page_size - offset);
630 	if (length <= 0) {
631 		iod->first_dma = 0;
632 		goto done;
633 	}
634 
635 	dma_len -= (page_size - offset);
636 	if (dma_len) {
637 		dma_addr += (page_size - offset);
638 	} else {
639 		sg = sg_next(sg);
640 		dma_addr = sg_dma_address(sg);
641 		dma_len = sg_dma_len(sg);
642 	}
643 
644 	if (length <= page_size) {
645 		iod->first_dma = dma_addr;
646 		goto done;
647 	}
648 
649 	nprps = DIV_ROUND_UP(length, page_size);
650 	if (nprps <= (256 / 8)) {
651 		pool = dev->prp_small_pool;
652 		iod->npages = 0;
653 	} else {
654 		pool = dev->prp_page_pool;
655 		iod->npages = 1;
656 	}
657 
658 	prp_list = dma_pool_alloc(pool, GFP_ATOMIC, &prp_dma);
659 	if (!prp_list) {
660 		iod->first_dma = dma_addr;
661 		iod->npages = -1;
662 		return BLK_STS_RESOURCE;
663 	}
664 	list[0] = prp_list;
665 	iod->first_dma = prp_dma;
666 	i = 0;
667 	for (;;) {
668 		if (i == page_size >> 3) {
669 			__le64 *old_prp_list = prp_list;
670 			prp_list = dma_pool_alloc(pool, GFP_ATOMIC, &prp_dma);
671 			if (!prp_list)
672 				return BLK_STS_RESOURCE;
673 			list[iod->npages++] = prp_list;
674 			prp_list[0] = old_prp_list[i - 1];
675 			old_prp_list[i - 1] = cpu_to_le64(prp_dma);
676 			i = 1;
677 		}
678 		prp_list[i++] = cpu_to_le64(dma_addr);
679 		dma_len -= page_size;
680 		dma_addr += page_size;
681 		length -= page_size;
682 		if (length <= 0)
683 			break;
684 		if (dma_len > 0)
685 			continue;
686 		if (unlikely(dma_len < 0))
687 			goto bad_sgl;
688 		sg = sg_next(sg);
689 		dma_addr = sg_dma_address(sg);
690 		dma_len = sg_dma_len(sg);
691 	}
692 
693 done:
694 	cmnd->dptr.prp1 = cpu_to_le64(sg_dma_address(iod->sg));
695 	cmnd->dptr.prp2 = cpu_to_le64(iod->first_dma);
696 
697 	return BLK_STS_OK;
698 
699  bad_sgl:
700 	WARN(DO_ONCE(nvme_print_sgl, iod->sg, iod->nents),
701 			"Invalid SGL for payload:%d nents:%d\n",
702 			blk_rq_payload_bytes(req), iod->nents);
703 	return BLK_STS_IOERR;
704 }
705 
706 static void nvme_pci_sgl_set_data(struct nvme_sgl_desc *sge,
707 		struct scatterlist *sg)
708 {
709 	sge->addr = cpu_to_le64(sg_dma_address(sg));
710 	sge->length = cpu_to_le32(sg_dma_len(sg));
711 	sge->type = NVME_SGL_FMT_DATA_DESC << 4;
712 }
713 
714 static void nvme_pci_sgl_set_seg(struct nvme_sgl_desc *sge,
715 		dma_addr_t dma_addr, int entries)
716 {
717 	sge->addr = cpu_to_le64(dma_addr);
718 	if (entries < SGES_PER_PAGE) {
719 		sge->length = cpu_to_le32(entries * sizeof(*sge));
720 		sge->type = NVME_SGL_FMT_LAST_SEG_DESC << 4;
721 	} else {
722 		sge->length = cpu_to_le32(PAGE_SIZE);
723 		sge->type = NVME_SGL_FMT_SEG_DESC << 4;
724 	}
725 }
726 
727 static blk_status_t nvme_pci_setup_sgls(struct nvme_dev *dev,
728 		struct request *req, struct nvme_rw_command *cmd, int entries)
729 {
730 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
731 	struct dma_pool *pool;
732 	struct nvme_sgl_desc *sg_list;
733 	struct scatterlist *sg = iod->sg;
734 	dma_addr_t sgl_dma;
735 	int i = 0;
736 
737 	/* setting the transfer type as SGL */
738 	cmd->flags = NVME_CMD_SGL_METABUF;
739 
740 	if (entries == 1) {
741 		nvme_pci_sgl_set_data(&cmd->dptr.sgl, sg);
742 		return BLK_STS_OK;
743 	}
744 
745 	if (entries <= (256 / sizeof(struct nvme_sgl_desc))) {
746 		pool = dev->prp_small_pool;
747 		iod->npages = 0;
748 	} else {
749 		pool = dev->prp_page_pool;
750 		iod->npages = 1;
751 	}
752 
753 	sg_list = dma_pool_alloc(pool, GFP_ATOMIC, &sgl_dma);
754 	if (!sg_list) {
755 		iod->npages = -1;
756 		return BLK_STS_RESOURCE;
757 	}
758 
759 	nvme_pci_iod_list(req)[0] = sg_list;
760 	iod->first_dma = sgl_dma;
761 
762 	nvme_pci_sgl_set_seg(&cmd->dptr.sgl, sgl_dma, entries);
763 
764 	do {
765 		if (i == SGES_PER_PAGE) {
766 			struct nvme_sgl_desc *old_sg_desc = sg_list;
767 			struct nvme_sgl_desc *link = &old_sg_desc[i - 1];
768 
769 			sg_list = dma_pool_alloc(pool, GFP_ATOMIC, &sgl_dma);
770 			if (!sg_list)
771 				return BLK_STS_RESOURCE;
772 
773 			i = 0;
774 			nvme_pci_iod_list(req)[iod->npages++] = sg_list;
775 			sg_list[i++] = *link;
776 			nvme_pci_sgl_set_seg(link, sgl_dma, entries);
777 		}
778 
779 		nvme_pci_sgl_set_data(&sg_list[i++], sg);
780 		sg = sg_next(sg);
781 	} while (--entries > 0);
782 
783 	return BLK_STS_OK;
784 }
785 
786 static blk_status_t nvme_map_data(struct nvme_dev *dev, struct request *req,
787 		struct nvme_command *cmnd)
788 {
789 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
790 	struct request_queue *q = req->q;
791 	enum dma_data_direction dma_dir = rq_data_dir(req) ?
792 			DMA_TO_DEVICE : DMA_FROM_DEVICE;
793 	blk_status_t ret = BLK_STS_IOERR;
794 	int nr_mapped;
795 
796 	sg_init_table(iod->sg, blk_rq_nr_phys_segments(req));
797 	iod->nents = blk_rq_map_sg(q, req, iod->sg);
798 	if (!iod->nents)
799 		goto out;
800 
801 	ret = BLK_STS_RESOURCE;
802 	nr_mapped = dma_map_sg_attrs(dev->dev, iod->sg, iod->nents, dma_dir,
803 			DMA_ATTR_NO_WARN);
804 	if (!nr_mapped)
805 		goto out;
806 
807 	if (iod->use_sgl)
808 		ret = nvme_pci_setup_sgls(dev, req, &cmnd->rw, nr_mapped);
809 	else
810 		ret = nvme_pci_setup_prps(dev, req, &cmnd->rw);
811 
812 	if (ret != BLK_STS_OK)
813 		goto out_unmap;
814 
815 	ret = BLK_STS_IOERR;
816 	if (blk_integrity_rq(req)) {
817 		if (blk_rq_count_integrity_sg(q, req->bio) != 1)
818 			goto out_unmap;
819 
820 		sg_init_table(&iod->meta_sg, 1);
821 		if (blk_rq_map_integrity_sg(q, req->bio, &iod->meta_sg) != 1)
822 			goto out_unmap;
823 
824 		if (req_op(req) == REQ_OP_WRITE)
825 			nvme_dif_remap(req, nvme_dif_prep);
826 
827 		if (!dma_map_sg(dev->dev, &iod->meta_sg, 1, dma_dir))
828 			goto out_unmap;
829 	}
830 
831 	if (blk_integrity_rq(req))
832 		cmnd->rw.metadata = cpu_to_le64(sg_dma_address(&iod->meta_sg));
833 	return BLK_STS_OK;
834 
835 out_unmap:
836 	dma_unmap_sg(dev->dev, iod->sg, iod->nents, dma_dir);
837 out:
838 	return ret;
839 }
840 
841 static void nvme_unmap_data(struct nvme_dev *dev, struct request *req)
842 {
843 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
844 	enum dma_data_direction dma_dir = rq_data_dir(req) ?
845 			DMA_TO_DEVICE : DMA_FROM_DEVICE;
846 
847 	if (iod->nents) {
848 		dma_unmap_sg(dev->dev, iod->sg, iod->nents, dma_dir);
849 		if (blk_integrity_rq(req)) {
850 			if (req_op(req) == REQ_OP_READ)
851 				nvme_dif_remap(req, nvme_dif_complete);
852 			dma_unmap_sg(dev->dev, &iod->meta_sg, 1, dma_dir);
853 		}
854 	}
855 
856 	nvme_cleanup_cmd(req);
857 	nvme_free_iod(dev, req);
858 }
859 
860 /*
861  * NOTE: ns is NULL when called on the admin queue.
862  */
863 static blk_status_t nvme_queue_rq(struct blk_mq_hw_ctx *hctx,
864 			 const struct blk_mq_queue_data *bd)
865 {
866 	struct nvme_ns *ns = hctx->queue->queuedata;
867 	struct nvme_queue *nvmeq = hctx->driver_data;
868 	struct nvme_dev *dev = nvmeq->dev;
869 	struct request *req = bd->rq;
870 	struct nvme_command cmnd;
871 	blk_status_t ret;
872 
873 	/*
874 	 * We should not need to do this, but we're still using this to
875 	 * ensure we can drain requests on a dying queue.
876 	 */
877 	if (unlikely(nvmeq->cq_vector < 0))
878 		return BLK_STS_IOERR;
879 
880 	ret = nvme_setup_cmd(ns, req, &cmnd);
881 	if (ret)
882 		return ret;
883 
884 	ret = nvme_init_iod(req, dev);
885 	if (ret)
886 		goto out_free_cmd;
887 
888 	if (blk_rq_nr_phys_segments(req)) {
889 		ret = nvme_map_data(dev, req, &cmnd);
890 		if (ret)
891 			goto out_cleanup_iod;
892 	}
893 
894 	blk_mq_start_request(req);
895 	nvme_submit_cmd(nvmeq, &cmnd);
896 	return BLK_STS_OK;
897 out_cleanup_iod:
898 	nvme_free_iod(dev, req);
899 out_free_cmd:
900 	nvme_cleanup_cmd(req);
901 	return ret;
902 }
903 
904 static void nvme_pci_complete_rq(struct request *req)
905 {
906 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
907 
908 	nvme_unmap_data(iod->nvmeq->dev, req);
909 	nvme_complete_rq(req);
910 }
911 
912 /* We read the CQE phase first to check if the rest of the entry is valid */
913 static inline bool nvme_cqe_pending(struct nvme_queue *nvmeq)
914 {
915 	return (le16_to_cpu(nvmeq->cqes[nvmeq->cq_head].status) & 1) ==
916 			nvmeq->cq_phase;
917 }
918 
919 static inline void nvme_ring_cq_doorbell(struct nvme_queue *nvmeq)
920 {
921 	u16 head = nvmeq->cq_head;
922 
923 	if (likely(nvmeq->cq_vector >= 0)) {
924 		if (nvme_dbbuf_update_and_check_event(head, nvmeq->dbbuf_cq_db,
925 						      nvmeq->dbbuf_cq_ei))
926 			writel(head, nvmeq->q_db + nvmeq->dev->db_stride);
927 	}
928 }
929 
930 static inline void nvme_handle_cqe(struct nvme_queue *nvmeq, u16 idx)
931 {
932 	volatile struct nvme_completion *cqe = &nvmeq->cqes[idx];
933 	struct request *req;
934 
935 	if (unlikely(cqe->command_id >= nvmeq->q_depth)) {
936 		dev_warn(nvmeq->dev->ctrl.device,
937 			"invalid id %d completed on queue %d\n",
938 			cqe->command_id, le16_to_cpu(cqe->sq_id));
939 		return;
940 	}
941 
942 	/*
943 	 * AEN requests are special as they don't time out and can
944 	 * survive any kind of queue freeze and often don't respond to
945 	 * aborts.  We don't even bother to allocate a struct request
946 	 * for them but rather special case them here.
947 	 */
948 	if (unlikely(nvmeq->qid == 0 &&
949 			cqe->command_id >= NVME_AQ_BLK_MQ_DEPTH)) {
950 		nvme_complete_async_event(&nvmeq->dev->ctrl,
951 				cqe->status, &cqe->result);
952 		return;
953 	}
954 
955 	req = blk_mq_tag_to_rq(*nvmeq->tags, cqe->command_id);
956 	nvme_end_request(req, cqe->status, cqe->result);
957 }
958 
959 static void nvme_complete_cqes(struct nvme_queue *nvmeq, u16 start, u16 end)
960 {
961 	while (start != end) {
962 		nvme_handle_cqe(nvmeq, start);
963 		if (++start == nvmeq->q_depth)
964 			start = 0;
965 	}
966 }
967 
968 static inline void nvme_update_cq_head(struct nvme_queue *nvmeq)
969 {
970 	if (++nvmeq->cq_head == nvmeq->q_depth) {
971 		nvmeq->cq_head = 0;
972 		nvmeq->cq_phase = !nvmeq->cq_phase;
973 	}
974 }
975 
976 static inline bool nvme_process_cq(struct nvme_queue *nvmeq, u16 *start,
977 		u16 *end, int tag)
978 {
979 	bool found = false;
980 
981 	*start = nvmeq->cq_head;
982 	while (!found && nvme_cqe_pending(nvmeq)) {
983 		if (nvmeq->cqes[nvmeq->cq_head].command_id == tag)
984 			found = true;
985 		nvme_update_cq_head(nvmeq);
986 	}
987 	*end = nvmeq->cq_head;
988 
989 	if (*start != *end)
990 		nvme_ring_cq_doorbell(nvmeq);
991 	return found;
992 }
993 
994 static irqreturn_t nvme_irq(int irq, void *data)
995 {
996 	struct nvme_queue *nvmeq = data;
997 	irqreturn_t ret = IRQ_NONE;
998 	u16 start, end;
999 
1000 	spin_lock(&nvmeq->cq_lock);
1001 	if (nvmeq->cq_head != nvmeq->last_cq_head)
1002 		ret = IRQ_HANDLED;
1003 	nvme_process_cq(nvmeq, &start, &end, -1);
1004 	nvmeq->last_cq_head = nvmeq->cq_head;
1005 	spin_unlock(&nvmeq->cq_lock);
1006 
1007 	if (start != end) {
1008 		nvme_complete_cqes(nvmeq, start, end);
1009 		return IRQ_HANDLED;
1010 	}
1011 
1012 	return ret;
1013 }
1014 
1015 static irqreturn_t nvme_irq_check(int irq, void *data)
1016 {
1017 	struct nvme_queue *nvmeq = data;
1018 	if (nvme_cqe_pending(nvmeq))
1019 		return IRQ_WAKE_THREAD;
1020 	return IRQ_NONE;
1021 }
1022 
1023 static int __nvme_poll(struct nvme_queue *nvmeq, unsigned int tag)
1024 {
1025 	u16 start, end;
1026 	bool found;
1027 
1028 	if (!nvme_cqe_pending(nvmeq))
1029 		return 0;
1030 
1031 	spin_lock_irq(&nvmeq->cq_lock);
1032 	found = nvme_process_cq(nvmeq, &start, &end, tag);
1033 	spin_unlock_irq(&nvmeq->cq_lock);
1034 
1035 	nvme_complete_cqes(nvmeq, start, end);
1036 	return found;
1037 }
1038 
1039 static int nvme_poll(struct blk_mq_hw_ctx *hctx, unsigned int tag)
1040 {
1041 	struct nvme_queue *nvmeq = hctx->driver_data;
1042 
1043 	return __nvme_poll(nvmeq, tag);
1044 }
1045 
1046 static void nvme_pci_submit_async_event(struct nvme_ctrl *ctrl)
1047 {
1048 	struct nvme_dev *dev = to_nvme_dev(ctrl);
1049 	struct nvme_queue *nvmeq = &dev->queues[0];
1050 	struct nvme_command c;
1051 
1052 	memset(&c, 0, sizeof(c));
1053 	c.common.opcode = nvme_admin_async_event;
1054 	c.common.command_id = NVME_AQ_BLK_MQ_DEPTH;
1055 	nvme_submit_cmd(nvmeq, &c);
1056 }
1057 
1058 static int adapter_delete_queue(struct nvme_dev *dev, u8 opcode, u16 id)
1059 {
1060 	struct nvme_command c;
1061 
1062 	memset(&c, 0, sizeof(c));
1063 	c.delete_queue.opcode = opcode;
1064 	c.delete_queue.qid = cpu_to_le16(id);
1065 
1066 	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1067 }
1068 
1069 static int adapter_alloc_cq(struct nvme_dev *dev, u16 qid,
1070 		struct nvme_queue *nvmeq, s16 vector)
1071 {
1072 	struct nvme_command c;
1073 	int flags = NVME_QUEUE_PHYS_CONTIG | NVME_CQ_IRQ_ENABLED;
1074 
1075 	/*
1076 	 * Note: we (ab)use the fact that the prp fields survive if no data
1077 	 * is attached to the request.
1078 	 */
1079 	memset(&c, 0, sizeof(c));
1080 	c.create_cq.opcode = nvme_admin_create_cq;
1081 	c.create_cq.prp1 = cpu_to_le64(nvmeq->cq_dma_addr);
1082 	c.create_cq.cqid = cpu_to_le16(qid);
1083 	c.create_cq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
1084 	c.create_cq.cq_flags = cpu_to_le16(flags);
1085 	c.create_cq.irq_vector = cpu_to_le16(vector);
1086 
1087 	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1088 }
1089 
1090 static int adapter_alloc_sq(struct nvme_dev *dev, u16 qid,
1091 						struct nvme_queue *nvmeq)
1092 {
1093 	struct nvme_ctrl *ctrl = &dev->ctrl;
1094 	struct nvme_command c;
1095 	int flags = NVME_QUEUE_PHYS_CONTIG;
1096 
1097 	/*
1098 	 * Some drives have a bug that auto-enables WRRU if MEDIUM isn't
1099 	 * set. Since URGENT priority is zeroes, it makes all queues
1100 	 * URGENT.
1101 	 */
1102 	if (ctrl->quirks & NVME_QUIRK_MEDIUM_PRIO_SQ)
1103 		flags |= NVME_SQ_PRIO_MEDIUM;
1104 
1105 	/*
1106 	 * Note: we (ab)use the fact that the prp fields survive if no data
1107 	 * is attached to the request.
1108 	 */
1109 	memset(&c, 0, sizeof(c));
1110 	c.create_sq.opcode = nvme_admin_create_sq;
1111 	c.create_sq.prp1 = cpu_to_le64(nvmeq->sq_dma_addr);
1112 	c.create_sq.sqid = cpu_to_le16(qid);
1113 	c.create_sq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
1114 	c.create_sq.sq_flags = cpu_to_le16(flags);
1115 	c.create_sq.cqid = cpu_to_le16(qid);
1116 
1117 	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1118 }
1119 
1120 static int adapter_delete_cq(struct nvme_dev *dev, u16 cqid)
1121 {
1122 	return adapter_delete_queue(dev, nvme_admin_delete_cq, cqid);
1123 }
1124 
1125 static int adapter_delete_sq(struct nvme_dev *dev, u16 sqid)
1126 {
1127 	return adapter_delete_queue(dev, nvme_admin_delete_sq, sqid);
1128 }
1129 
1130 static void abort_endio(struct request *req, blk_status_t error)
1131 {
1132 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
1133 	struct nvme_queue *nvmeq = iod->nvmeq;
1134 
1135 	dev_warn(nvmeq->dev->ctrl.device,
1136 		 "Abort status: 0x%x", nvme_req(req)->status);
1137 	atomic_inc(&nvmeq->dev->ctrl.abort_limit);
1138 	blk_mq_free_request(req);
1139 }
1140 
1141 static bool nvme_should_reset(struct nvme_dev *dev, u32 csts)
1142 {
1143 
1144 	/* If true, indicates loss of adapter communication, possibly by a
1145 	 * NVMe Subsystem reset.
1146 	 */
1147 	bool nssro = dev->subsystem && (csts & NVME_CSTS_NSSRO);
1148 
1149 	/* If there is a reset/reinit ongoing, we shouldn't reset again. */
1150 	switch (dev->ctrl.state) {
1151 	case NVME_CTRL_RESETTING:
1152 	case NVME_CTRL_CONNECTING:
1153 		return false;
1154 	default:
1155 		break;
1156 	}
1157 
1158 	/* We shouldn't reset unless the controller is on fatal error state
1159 	 * _or_ if we lost the communication with it.
1160 	 */
1161 	if (!(csts & NVME_CSTS_CFS) && !nssro)
1162 		return false;
1163 
1164 	return true;
1165 }
1166 
1167 static void nvme_warn_reset(struct nvme_dev *dev, u32 csts)
1168 {
1169 	/* Read a config register to help see what died. */
1170 	u16 pci_status;
1171 	int result;
1172 
1173 	result = pci_read_config_word(to_pci_dev(dev->dev), PCI_STATUS,
1174 				      &pci_status);
1175 	if (result == PCIBIOS_SUCCESSFUL)
1176 		dev_warn(dev->ctrl.device,
1177 			 "controller is down; will reset: CSTS=0x%x, PCI_STATUS=0x%hx\n",
1178 			 csts, pci_status);
1179 	else
1180 		dev_warn(dev->ctrl.device,
1181 			 "controller is down; will reset: CSTS=0x%x, PCI_STATUS read failed (%d)\n",
1182 			 csts, result);
1183 }
1184 
1185 static enum blk_eh_timer_return nvme_timeout(struct request *req, bool reserved)
1186 {
1187 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
1188 	struct nvme_queue *nvmeq = iod->nvmeq;
1189 	struct nvme_dev *dev = nvmeq->dev;
1190 	struct request *abort_req;
1191 	struct nvme_command cmd;
1192 	u32 csts = readl(dev->bar + NVME_REG_CSTS);
1193 
1194 	/* If PCI error recovery process is happening, we cannot reset or
1195 	 * the recovery mechanism will surely fail.
1196 	 */
1197 	mb();
1198 	if (pci_channel_offline(to_pci_dev(dev->dev)))
1199 		return BLK_EH_RESET_TIMER;
1200 
1201 	/*
1202 	 * Reset immediately if the controller is failed
1203 	 */
1204 	if (nvme_should_reset(dev, csts)) {
1205 		nvme_warn_reset(dev, csts);
1206 		nvme_dev_disable(dev, false);
1207 		nvme_reset_ctrl(&dev->ctrl);
1208 		return BLK_EH_DONE;
1209 	}
1210 
1211 	/*
1212 	 * Did we miss an interrupt?
1213 	 */
1214 	if (__nvme_poll(nvmeq, req->tag)) {
1215 		dev_warn(dev->ctrl.device,
1216 			 "I/O %d QID %d timeout, completion polled\n",
1217 			 req->tag, nvmeq->qid);
1218 		return BLK_EH_DONE;
1219 	}
1220 
1221 	/*
1222 	 * Shutdown immediately if controller times out while starting. The
1223 	 * reset work will see the pci device disabled when it gets the forced
1224 	 * cancellation error. All outstanding requests are completed on
1225 	 * shutdown, so we return BLK_EH_DONE.
1226 	 */
1227 	switch (dev->ctrl.state) {
1228 	case NVME_CTRL_CONNECTING:
1229 	case NVME_CTRL_RESETTING:
1230 		dev_warn_ratelimited(dev->ctrl.device,
1231 			 "I/O %d QID %d timeout, disable controller\n",
1232 			 req->tag, nvmeq->qid);
1233 		nvme_dev_disable(dev, false);
1234 		nvme_req(req)->flags |= NVME_REQ_CANCELLED;
1235 		return BLK_EH_DONE;
1236 	default:
1237 		break;
1238 	}
1239 
1240 	/*
1241  	 * Shutdown the controller immediately and schedule a reset if the
1242  	 * command was already aborted once before and still hasn't been
1243  	 * returned to the driver, or if this is the admin queue.
1244 	 */
1245 	if (!nvmeq->qid || iod->aborted) {
1246 		dev_warn(dev->ctrl.device,
1247 			 "I/O %d QID %d timeout, reset controller\n",
1248 			 req->tag, nvmeq->qid);
1249 		nvme_dev_disable(dev, false);
1250 		nvme_reset_ctrl(&dev->ctrl);
1251 
1252 		nvme_req(req)->flags |= NVME_REQ_CANCELLED;
1253 		return BLK_EH_DONE;
1254 	}
1255 
1256 	if (atomic_dec_return(&dev->ctrl.abort_limit) < 0) {
1257 		atomic_inc(&dev->ctrl.abort_limit);
1258 		return BLK_EH_RESET_TIMER;
1259 	}
1260 	iod->aborted = 1;
1261 
1262 	memset(&cmd, 0, sizeof(cmd));
1263 	cmd.abort.opcode = nvme_admin_abort_cmd;
1264 	cmd.abort.cid = req->tag;
1265 	cmd.abort.sqid = cpu_to_le16(nvmeq->qid);
1266 
1267 	dev_warn(nvmeq->dev->ctrl.device,
1268 		"I/O %d QID %d timeout, aborting\n",
1269 		 req->tag, nvmeq->qid);
1270 
1271 	abort_req = nvme_alloc_request(dev->ctrl.admin_q, &cmd,
1272 			BLK_MQ_REQ_NOWAIT, NVME_QID_ANY);
1273 	if (IS_ERR(abort_req)) {
1274 		atomic_inc(&dev->ctrl.abort_limit);
1275 		return BLK_EH_RESET_TIMER;
1276 	}
1277 
1278 	abort_req->timeout = ADMIN_TIMEOUT;
1279 	abort_req->end_io_data = NULL;
1280 	blk_execute_rq_nowait(abort_req->q, NULL, abort_req, 0, abort_endio);
1281 
1282 	/*
1283 	 * The aborted req will be completed on receiving the abort req.
1284 	 * We enable the timer again. If hit twice, it'll cause a device reset,
1285 	 * as the device then is in a faulty state.
1286 	 */
1287 	return BLK_EH_RESET_TIMER;
1288 }
1289 
1290 static void nvme_free_queue(struct nvme_queue *nvmeq)
1291 {
1292 	dma_free_coherent(nvmeq->q_dmadev, CQ_SIZE(nvmeq->q_depth),
1293 				(void *)nvmeq->cqes, nvmeq->cq_dma_addr);
1294 	if (nvmeq->sq_cmds)
1295 		dma_free_coherent(nvmeq->q_dmadev, SQ_SIZE(nvmeq->q_depth),
1296 					nvmeq->sq_cmds, nvmeq->sq_dma_addr);
1297 }
1298 
1299 static void nvme_free_queues(struct nvme_dev *dev, int lowest)
1300 {
1301 	int i;
1302 
1303 	for (i = dev->ctrl.queue_count - 1; i >= lowest; i--) {
1304 		dev->ctrl.queue_count--;
1305 		nvme_free_queue(&dev->queues[i]);
1306 	}
1307 }
1308 
1309 /**
1310  * nvme_suspend_queue - put queue into suspended state
1311  * @nvmeq - queue to suspend
1312  */
1313 static int nvme_suspend_queue(struct nvme_queue *nvmeq)
1314 {
1315 	int vector;
1316 
1317 	spin_lock_irq(&nvmeq->cq_lock);
1318 	if (nvmeq->cq_vector == -1) {
1319 		spin_unlock_irq(&nvmeq->cq_lock);
1320 		return 1;
1321 	}
1322 	vector = nvmeq->cq_vector;
1323 	nvmeq->dev->online_queues--;
1324 	nvmeq->cq_vector = -1;
1325 	spin_unlock_irq(&nvmeq->cq_lock);
1326 
1327 	/*
1328 	 * Ensure that nvme_queue_rq() sees it ->cq_vector == -1 without
1329 	 * having to grab the lock.
1330 	 */
1331 	mb();
1332 
1333 	if (!nvmeq->qid && nvmeq->dev->ctrl.admin_q)
1334 		blk_mq_quiesce_queue(nvmeq->dev->ctrl.admin_q);
1335 
1336 	pci_free_irq(to_pci_dev(nvmeq->dev->dev), vector, nvmeq);
1337 
1338 	return 0;
1339 }
1340 
1341 static void nvme_disable_admin_queue(struct nvme_dev *dev, bool shutdown)
1342 {
1343 	struct nvme_queue *nvmeq = &dev->queues[0];
1344 	u16 start, end;
1345 
1346 	if (shutdown)
1347 		nvme_shutdown_ctrl(&dev->ctrl);
1348 	else
1349 		nvme_disable_ctrl(&dev->ctrl, dev->ctrl.cap);
1350 
1351 	spin_lock_irq(&nvmeq->cq_lock);
1352 	nvme_process_cq(nvmeq, &start, &end, -1);
1353 	spin_unlock_irq(&nvmeq->cq_lock);
1354 
1355 	nvme_complete_cqes(nvmeq, start, end);
1356 }
1357 
1358 static int nvme_cmb_qdepth(struct nvme_dev *dev, int nr_io_queues,
1359 				int entry_size)
1360 {
1361 	int q_depth = dev->q_depth;
1362 	unsigned q_size_aligned = roundup(q_depth * entry_size,
1363 					  dev->ctrl.page_size);
1364 
1365 	if (q_size_aligned * nr_io_queues > dev->cmb_size) {
1366 		u64 mem_per_q = div_u64(dev->cmb_size, nr_io_queues);
1367 		mem_per_q = round_down(mem_per_q, dev->ctrl.page_size);
1368 		q_depth = div_u64(mem_per_q, entry_size);
1369 
1370 		/*
1371 		 * Ensure the reduced q_depth is above some threshold where it
1372 		 * would be better to map queues in system memory with the
1373 		 * original depth
1374 		 */
1375 		if (q_depth < 64)
1376 			return -ENOMEM;
1377 	}
1378 
1379 	return q_depth;
1380 }
1381 
1382 static int nvme_alloc_sq_cmds(struct nvme_dev *dev, struct nvme_queue *nvmeq,
1383 				int qid, int depth)
1384 {
1385 	/* CMB SQEs will be mapped before creation */
1386 	if (qid && dev->cmb && use_cmb_sqes && (dev->cmbsz & NVME_CMBSZ_SQS))
1387 		return 0;
1388 
1389 	nvmeq->sq_cmds = dma_alloc_coherent(dev->dev, SQ_SIZE(depth),
1390 					    &nvmeq->sq_dma_addr, GFP_KERNEL);
1391 	if (!nvmeq->sq_cmds)
1392 		return -ENOMEM;
1393 	return 0;
1394 }
1395 
1396 static int nvme_alloc_queue(struct nvme_dev *dev, int qid, int depth)
1397 {
1398 	struct nvme_queue *nvmeq = &dev->queues[qid];
1399 
1400 	if (dev->ctrl.queue_count > qid)
1401 		return 0;
1402 
1403 	nvmeq->cqes = dma_zalloc_coherent(dev->dev, CQ_SIZE(depth),
1404 					  &nvmeq->cq_dma_addr, GFP_KERNEL);
1405 	if (!nvmeq->cqes)
1406 		goto free_nvmeq;
1407 
1408 	if (nvme_alloc_sq_cmds(dev, nvmeq, qid, depth))
1409 		goto free_cqdma;
1410 
1411 	nvmeq->q_dmadev = dev->dev;
1412 	nvmeq->dev = dev;
1413 	spin_lock_init(&nvmeq->sq_lock);
1414 	spin_lock_init(&nvmeq->cq_lock);
1415 	nvmeq->cq_head = 0;
1416 	nvmeq->cq_phase = 1;
1417 	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
1418 	nvmeq->q_depth = depth;
1419 	nvmeq->qid = qid;
1420 	nvmeq->cq_vector = -1;
1421 	dev->ctrl.queue_count++;
1422 
1423 	return 0;
1424 
1425  free_cqdma:
1426 	dma_free_coherent(dev->dev, CQ_SIZE(depth), (void *)nvmeq->cqes,
1427 							nvmeq->cq_dma_addr);
1428  free_nvmeq:
1429 	return -ENOMEM;
1430 }
1431 
1432 static int queue_request_irq(struct nvme_queue *nvmeq)
1433 {
1434 	struct pci_dev *pdev = to_pci_dev(nvmeq->dev->dev);
1435 	int nr = nvmeq->dev->ctrl.instance;
1436 
1437 	if (use_threaded_interrupts) {
1438 		return pci_request_irq(pdev, nvmeq->cq_vector, nvme_irq_check,
1439 				nvme_irq, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
1440 	} else {
1441 		return pci_request_irq(pdev, nvmeq->cq_vector, nvme_irq,
1442 				NULL, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
1443 	}
1444 }
1445 
1446 static void nvme_init_queue(struct nvme_queue *nvmeq, u16 qid)
1447 {
1448 	struct nvme_dev *dev = nvmeq->dev;
1449 
1450 	spin_lock_irq(&nvmeq->cq_lock);
1451 	nvmeq->sq_tail = 0;
1452 	nvmeq->cq_head = 0;
1453 	nvmeq->cq_phase = 1;
1454 	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
1455 	memset((void *)nvmeq->cqes, 0, CQ_SIZE(nvmeq->q_depth));
1456 	nvme_dbbuf_init(dev, nvmeq, qid);
1457 	dev->online_queues++;
1458 	spin_unlock_irq(&nvmeq->cq_lock);
1459 }
1460 
1461 static int nvme_create_queue(struct nvme_queue *nvmeq, int qid)
1462 {
1463 	struct nvme_dev *dev = nvmeq->dev;
1464 	int result;
1465 	s16 vector;
1466 
1467 	if (dev->cmb && use_cmb_sqes && (dev->cmbsz & NVME_CMBSZ_SQS)) {
1468 		unsigned offset = (qid - 1) * roundup(SQ_SIZE(nvmeq->q_depth),
1469 						      dev->ctrl.page_size);
1470 		nvmeq->sq_dma_addr = dev->cmb_bus_addr + offset;
1471 		nvmeq->sq_cmds_io = dev->cmb + offset;
1472 	}
1473 
1474 	/*
1475 	 * A queue's vector matches the queue identifier unless the controller
1476 	 * has only one vector available.
1477 	 */
1478 	vector = dev->num_vecs == 1 ? 0 : qid;
1479 	result = adapter_alloc_cq(dev, qid, nvmeq, vector);
1480 	if (result < 0)
1481 		goto out;
1482 
1483 	result = adapter_alloc_sq(dev, qid, nvmeq);
1484 	if (result < 0)
1485 		goto release_cq;
1486 
1487 	/*
1488 	 * Set cq_vector after alloc cq/sq, otherwise nvme_suspend_queue will
1489 	 * invoke free_irq for it and cause a 'Trying to free already-free IRQ
1490 	 * xxx' warning if the create CQ/SQ command times out.
1491 	 */
1492 	nvmeq->cq_vector = vector;
1493 	nvme_init_queue(nvmeq, qid);
1494 	result = queue_request_irq(nvmeq);
1495 	if (result < 0)
1496 		goto release_sq;
1497 
1498 	return result;
1499 
1500 release_sq:
1501 	nvmeq->cq_vector = -1;
1502 	dev->online_queues--;
1503 	adapter_delete_sq(dev, qid);
1504 release_cq:
1505 	adapter_delete_cq(dev, qid);
1506 out:
1507 	return result;
1508 }
1509 
1510 static const struct blk_mq_ops nvme_mq_admin_ops = {
1511 	.queue_rq	= nvme_queue_rq,
1512 	.complete	= nvme_pci_complete_rq,
1513 	.init_hctx	= nvme_admin_init_hctx,
1514 	.exit_hctx      = nvme_admin_exit_hctx,
1515 	.init_request	= nvme_init_request,
1516 	.timeout	= nvme_timeout,
1517 };
1518 
1519 static const struct blk_mq_ops nvme_mq_ops = {
1520 	.queue_rq	= nvme_queue_rq,
1521 	.complete	= nvme_pci_complete_rq,
1522 	.init_hctx	= nvme_init_hctx,
1523 	.init_request	= nvme_init_request,
1524 	.map_queues	= nvme_pci_map_queues,
1525 	.timeout	= nvme_timeout,
1526 	.poll		= nvme_poll,
1527 };
1528 
1529 static void nvme_dev_remove_admin(struct nvme_dev *dev)
1530 {
1531 	if (dev->ctrl.admin_q && !blk_queue_dying(dev->ctrl.admin_q)) {
1532 		/*
1533 		 * If the controller was reset during removal, it's possible
1534 		 * user requests may be waiting on a stopped queue. Start the
1535 		 * queue to flush these to completion.
1536 		 */
1537 		blk_mq_unquiesce_queue(dev->ctrl.admin_q);
1538 		blk_cleanup_queue(dev->ctrl.admin_q);
1539 		blk_mq_free_tag_set(&dev->admin_tagset);
1540 	}
1541 }
1542 
1543 static int nvme_alloc_admin_tags(struct nvme_dev *dev)
1544 {
1545 	if (!dev->ctrl.admin_q) {
1546 		dev->admin_tagset.ops = &nvme_mq_admin_ops;
1547 		dev->admin_tagset.nr_hw_queues = 1;
1548 
1549 		dev->admin_tagset.queue_depth = NVME_AQ_MQ_TAG_DEPTH;
1550 		dev->admin_tagset.timeout = ADMIN_TIMEOUT;
1551 		dev->admin_tagset.numa_node = dev_to_node(dev->dev);
1552 		dev->admin_tagset.cmd_size = nvme_pci_cmd_size(dev, false);
1553 		dev->admin_tagset.flags = BLK_MQ_F_NO_SCHED;
1554 		dev->admin_tagset.driver_data = dev;
1555 
1556 		if (blk_mq_alloc_tag_set(&dev->admin_tagset))
1557 			return -ENOMEM;
1558 		dev->ctrl.admin_tagset = &dev->admin_tagset;
1559 
1560 		dev->ctrl.admin_q = blk_mq_init_queue(&dev->admin_tagset);
1561 		if (IS_ERR(dev->ctrl.admin_q)) {
1562 			blk_mq_free_tag_set(&dev->admin_tagset);
1563 			return -ENOMEM;
1564 		}
1565 		if (!blk_get_queue(dev->ctrl.admin_q)) {
1566 			nvme_dev_remove_admin(dev);
1567 			dev->ctrl.admin_q = NULL;
1568 			return -ENODEV;
1569 		}
1570 	} else
1571 		blk_mq_unquiesce_queue(dev->ctrl.admin_q);
1572 
1573 	return 0;
1574 }
1575 
1576 static unsigned long db_bar_size(struct nvme_dev *dev, unsigned nr_io_queues)
1577 {
1578 	return NVME_REG_DBS + ((nr_io_queues + 1) * 8 * dev->db_stride);
1579 }
1580 
1581 static int nvme_remap_bar(struct nvme_dev *dev, unsigned long size)
1582 {
1583 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1584 
1585 	if (size <= dev->bar_mapped_size)
1586 		return 0;
1587 	if (size > pci_resource_len(pdev, 0))
1588 		return -ENOMEM;
1589 	if (dev->bar)
1590 		iounmap(dev->bar);
1591 	dev->bar = ioremap(pci_resource_start(pdev, 0), size);
1592 	if (!dev->bar) {
1593 		dev->bar_mapped_size = 0;
1594 		return -ENOMEM;
1595 	}
1596 	dev->bar_mapped_size = size;
1597 	dev->dbs = dev->bar + NVME_REG_DBS;
1598 
1599 	return 0;
1600 }
1601 
1602 static int nvme_pci_configure_admin_queue(struct nvme_dev *dev)
1603 {
1604 	int result;
1605 	u32 aqa;
1606 	struct nvme_queue *nvmeq;
1607 
1608 	result = nvme_remap_bar(dev, db_bar_size(dev, 0));
1609 	if (result < 0)
1610 		return result;
1611 
1612 	dev->subsystem = readl(dev->bar + NVME_REG_VS) >= NVME_VS(1, 1, 0) ?
1613 				NVME_CAP_NSSRC(dev->ctrl.cap) : 0;
1614 
1615 	if (dev->subsystem &&
1616 	    (readl(dev->bar + NVME_REG_CSTS) & NVME_CSTS_NSSRO))
1617 		writel(NVME_CSTS_NSSRO, dev->bar + NVME_REG_CSTS);
1618 
1619 	result = nvme_disable_ctrl(&dev->ctrl, dev->ctrl.cap);
1620 	if (result < 0)
1621 		return result;
1622 
1623 	result = nvme_alloc_queue(dev, 0, NVME_AQ_DEPTH);
1624 	if (result)
1625 		return result;
1626 
1627 	nvmeq = &dev->queues[0];
1628 	aqa = nvmeq->q_depth - 1;
1629 	aqa |= aqa << 16;
1630 
1631 	writel(aqa, dev->bar + NVME_REG_AQA);
1632 	lo_hi_writeq(nvmeq->sq_dma_addr, dev->bar + NVME_REG_ASQ);
1633 	lo_hi_writeq(nvmeq->cq_dma_addr, dev->bar + NVME_REG_ACQ);
1634 
1635 	result = nvme_enable_ctrl(&dev->ctrl, dev->ctrl.cap);
1636 	if (result)
1637 		return result;
1638 
1639 	nvmeq->cq_vector = 0;
1640 	nvme_init_queue(nvmeq, 0);
1641 	result = queue_request_irq(nvmeq);
1642 	if (result) {
1643 		nvmeq->cq_vector = -1;
1644 		return result;
1645 	}
1646 
1647 	return result;
1648 }
1649 
1650 static int nvme_create_io_queues(struct nvme_dev *dev)
1651 {
1652 	unsigned i, max;
1653 	int ret = 0;
1654 
1655 	for (i = dev->ctrl.queue_count; i <= dev->max_qid; i++) {
1656 		if (nvme_alloc_queue(dev, i, dev->q_depth)) {
1657 			ret = -ENOMEM;
1658 			break;
1659 		}
1660 	}
1661 
1662 	max = min(dev->max_qid, dev->ctrl.queue_count - 1);
1663 	for (i = dev->online_queues; i <= max; i++) {
1664 		ret = nvme_create_queue(&dev->queues[i], i);
1665 		if (ret)
1666 			break;
1667 	}
1668 
1669 	/*
1670 	 * Ignore failing Create SQ/CQ commands, we can continue with less
1671 	 * than the desired amount of queues, and even a controller without
1672 	 * I/O queues can still be used to issue admin commands.  This might
1673 	 * be useful to upgrade a buggy firmware for example.
1674 	 */
1675 	return ret >= 0 ? 0 : ret;
1676 }
1677 
1678 static ssize_t nvme_cmb_show(struct device *dev,
1679 			     struct device_attribute *attr,
1680 			     char *buf)
1681 {
1682 	struct nvme_dev *ndev = to_nvme_dev(dev_get_drvdata(dev));
1683 
1684 	return scnprintf(buf, PAGE_SIZE, "cmbloc : x%08x\ncmbsz  : x%08x\n",
1685 		       ndev->cmbloc, ndev->cmbsz);
1686 }
1687 static DEVICE_ATTR(cmb, S_IRUGO, nvme_cmb_show, NULL);
1688 
1689 static u64 nvme_cmb_size_unit(struct nvme_dev *dev)
1690 {
1691 	u8 szu = (dev->cmbsz >> NVME_CMBSZ_SZU_SHIFT) & NVME_CMBSZ_SZU_MASK;
1692 
1693 	return 1ULL << (12 + 4 * szu);
1694 }
1695 
1696 static u32 nvme_cmb_size(struct nvme_dev *dev)
1697 {
1698 	return (dev->cmbsz >> NVME_CMBSZ_SZ_SHIFT) & NVME_CMBSZ_SZ_MASK;
1699 }
1700 
1701 static void nvme_map_cmb(struct nvme_dev *dev)
1702 {
1703 	u64 size, offset;
1704 	resource_size_t bar_size;
1705 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1706 	int bar;
1707 
1708 	dev->cmbsz = readl(dev->bar + NVME_REG_CMBSZ);
1709 	if (!dev->cmbsz)
1710 		return;
1711 	dev->cmbloc = readl(dev->bar + NVME_REG_CMBLOC);
1712 
1713 	if (!use_cmb_sqes)
1714 		return;
1715 
1716 	size = nvme_cmb_size_unit(dev) * nvme_cmb_size(dev);
1717 	offset = nvme_cmb_size_unit(dev) * NVME_CMB_OFST(dev->cmbloc);
1718 	bar = NVME_CMB_BIR(dev->cmbloc);
1719 	bar_size = pci_resource_len(pdev, bar);
1720 
1721 	if (offset > bar_size)
1722 		return;
1723 
1724 	/*
1725 	 * Controllers may support a CMB size larger than their BAR,
1726 	 * for example, due to being behind a bridge. Reduce the CMB to
1727 	 * the reported size of the BAR
1728 	 */
1729 	if (size > bar_size - offset)
1730 		size = bar_size - offset;
1731 
1732 	dev->cmb = ioremap_wc(pci_resource_start(pdev, bar) + offset, size);
1733 	if (!dev->cmb)
1734 		return;
1735 	dev->cmb_bus_addr = pci_bus_address(pdev, bar) + offset;
1736 	dev->cmb_size = size;
1737 
1738 	if (sysfs_add_file_to_group(&dev->ctrl.device->kobj,
1739 				    &dev_attr_cmb.attr, NULL))
1740 		dev_warn(dev->ctrl.device,
1741 			 "failed to add sysfs attribute for CMB\n");
1742 }
1743 
1744 static inline void nvme_release_cmb(struct nvme_dev *dev)
1745 {
1746 	if (dev->cmb) {
1747 		iounmap(dev->cmb);
1748 		dev->cmb = NULL;
1749 		sysfs_remove_file_from_group(&dev->ctrl.device->kobj,
1750 					     &dev_attr_cmb.attr, NULL);
1751 		dev->cmbsz = 0;
1752 	}
1753 }
1754 
1755 static int nvme_set_host_mem(struct nvme_dev *dev, u32 bits)
1756 {
1757 	u64 dma_addr = dev->host_mem_descs_dma;
1758 	struct nvme_command c;
1759 	int ret;
1760 
1761 	memset(&c, 0, sizeof(c));
1762 	c.features.opcode	= nvme_admin_set_features;
1763 	c.features.fid		= cpu_to_le32(NVME_FEAT_HOST_MEM_BUF);
1764 	c.features.dword11	= cpu_to_le32(bits);
1765 	c.features.dword12	= cpu_to_le32(dev->host_mem_size >>
1766 					      ilog2(dev->ctrl.page_size));
1767 	c.features.dword13	= cpu_to_le32(lower_32_bits(dma_addr));
1768 	c.features.dword14	= cpu_to_le32(upper_32_bits(dma_addr));
1769 	c.features.dword15	= cpu_to_le32(dev->nr_host_mem_descs);
1770 
1771 	ret = nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1772 	if (ret) {
1773 		dev_warn(dev->ctrl.device,
1774 			 "failed to set host mem (err %d, flags %#x).\n",
1775 			 ret, bits);
1776 	}
1777 	return ret;
1778 }
1779 
1780 static void nvme_free_host_mem(struct nvme_dev *dev)
1781 {
1782 	int i;
1783 
1784 	for (i = 0; i < dev->nr_host_mem_descs; i++) {
1785 		struct nvme_host_mem_buf_desc *desc = &dev->host_mem_descs[i];
1786 		size_t size = le32_to_cpu(desc->size) * dev->ctrl.page_size;
1787 
1788 		dma_free_coherent(dev->dev, size, dev->host_mem_desc_bufs[i],
1789 				le64_to_cpu(desc->addr));
1790 	}
1791 
1792 	kfree(dev->host_mem_desc_bufs);
1793 	dev->host_mem_desc_bufs = NULL;
1794 	dma_free_coherent(dev->dev,
1795 			dev->nr_host_mem_descs * sizeof(*dev->host_mem_descs),
1796 			dev->host_mem_descs, dev->host_mem_descs_dma);
1797 	dev->host_mem_descs = NULL;
1798 	dev->nr_host_mem_descs = 0;
1799 }
1800 
1801 static int __nvme_alloc_host_mem(struct nvme_dev *dev, u64 preferred,
1802 		u32 chunk_size)
1803 {
1804 	struct nvme_host_mem_buf_desc *descs;
1805 	u32 max_entries, len;
1806 	dma_addr_t descs_dma;
1807 	int i = 0;
1808 	void **bufs;
1809 	u64 size, tmp;
1810 
1811 	tmp = (preferred + chunk_size - 1);
1812 	do_div(tmp, chunk_size);
1813 	max_entries = tmp;
1814 
1815 	if (dev->ctrl.hmmaxd && dev->ctrl.hmmaxd < max_entries)
1816 		max_entries = dev->ctrl.hmmaxd;
1817 
1818 	descs = dma_zalloc_coherent(dev->dev, max_entries * sizeof(*descs),
1819 			&descs_dma, GFP_KERNEL);
1820 	if (!descs)
1821 		goto out;
1822 
1823 	bufs = kcalloc(max_entries, sizeof(*bufs), GFP_KERNEL);
1824 	if (!bufs)
1825 		goto out_free_descs;
1826 
1827 	for (size = 0; size < preferred && i < max_entries; size += len) {
1828 		dma_addr_t dma_addr;
1829 
1830 		len = min_t(u64, chunk_size, preferred - size);
1831 		bufs[i] = dma_alloc_attrs(dev->dev, len, &dma_addr, GFP_KERNEL,
1832 				DMA_ATTR_NO_KERNEL_MAPPING | DMA_ATTR_NO_WARN);
1833 		if (!bufs[i])
1834 			break;
1835 
1836 		descs[i].addr = cpu_to_le64(dma_addr);
1837 		descs[i].size = cpu_to_le32(len / dev->ctrl.page_size);
1838 		i++;
1839 	}
1840 
1841 	if (!size)
1842 		goto out_free_bufs;
1843 
1844 	dev->nr_host_mem_descs = i;
1845 	dev->host_mem_size = size;
1846 	dev->host_mem_descs = descs;
1847 	dev->host_mem_descs_dma = descs_dma;
1848 	dev->host_mem_desc_bufs = bufs;
1849 	return 0;
1850 
1851 out_free_bufs:
1852 	while (--i >= 0) {
1853 		size_t size = le32_to_cpu(descs[i].size) * dev->ctrl.page_size;
1854 
1855 		dma_free_coherent(dev->dev, size, bufs[i],
1856 				le64_to_cpu(descs[i].addr));
1857 	}
1858 
1859 	kfree(bufs);
1860 out_free_descs:
1861 	dma_free_coherent(dev->dev, max_entries * sizeof(*descs), descs,
1862 			descs_dma);
1863 out:
1864 	dev->host_mem_descs = NULL;
1865 	return -ENOMEM;
1866 }
1867 
1868 static int nvme_alloc_host_mem(struct nvme_dev *dev, u64 min, u64 preferred)
1869 {
1870 	u32 chunk_size;
1871 
1872 	/* start big and work our way down */
1873 	for (chunk_size = min_t(u64, preferred, PAGE_SIZE * MAX_ORDER_NR_PAGES);
1874 	     chunk_size >= max_t(u32, dev->ctrl.hmminds * 4096, PAGE_SIZE * 2);
1875 	     chunk_size /= 2) {
1876 		if (!__nvme_alloc_host_mem(dev, preferred, chunk_size)) {
1877 			if (!min || dev->host_mem_size >= min)
1878 				return 0;
1879 			nvme_free_host_mem(dev);
1880 		}
1881 	}
1882 
1883 	return -ENOMEM;
1884 }
1885 
1886 static int nvme_setup_host_mem(struct nvme_dev *dev)
1887 {
1888 	u64 max = (u64)max_host_mem_size_mb * SZ_1M;
1889 	u64 preferred = (u64)dev->ctrl.hmpre * 4096;
1890 	u64 min = (u64)dev->ctrl.hmmin * 4096;
1891 	u32 enable_bits = NVME_HOST_MEM_ENABLE;
1892 	int ret;
1893 
1894 	preferred = min(preferred, max);
1895 	if (min > max) {
1896 		dev_warn(dev->ctrl.device,
1897 			"min host memory (%lld MiB) above limit (%d MiB).\n",
1898 			min >> ilog2(SZ_1M), max_host_mem_size_mb);
1899 		nvme_free_host_mem(dev);
1900 		return 0;
1901 	}
1902 
1903 	/*
1904 	 * If we already have a buffer allocated check if we can reuse it.
1905 	 */
1906 	if (dev->host_mem_descs) {
1907 		if (dev->host_mem_size >= min)
1908 			enable_bits |= NVME_HOST_MEM_RETURN;
1909 		else
1910 			nvme_free_host_mem(dev);
1911 	}
1912 
1913 	if (!dev->host_mem_descs) {
1914 		if (nvme_alloc_host_mem(dev, min, preferred)) {
1915 			dev_warn(dev->ctrl.device,
1916 				"failed to allocate host memory buffer.\n");
1917 			return 0; /* controller must work without HMB */
1918 		}
1919 
1920 		dev_info(dev->ctrl.device,
1921 			"allocated %lld MiB host memory buffer.\n",
1922 			dev->host_mem_size >> ilog2(SZ_1M));
1923 	}
1924 
1925 	ret = nvme_set_host_mem(dev, enable_bits);
1926 	if (ret)
1927 		nvme_free_host_mem(dev);
1928 	return ret;
1929 }
1930 
1931 static int nvme_setup_io_queues(struct nvme_dev *dev)
1932 {
1933 	struct nvme_queue *adminq = &dev->queues[0];
1934 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1935 	int result, nr_io_queues;
1936 	unsigned long size;
1937 
1938 	struct irq_affinity affd = {
1939 		.pre_vectors = 1
1940 	};
1941 
1942 	nr_io_queues = num_possible_cpus();
1943 	result = nvme_set_queue_count(&dev->ctrl, &nr_io_queues);
1944 	if (result < 0)
1945 		return result;
1946 
1947 	if (nr_io_queues == 0)
1948 		return 0;
1949 
1950 	if (dev->cmb && (dev->cmbsz & NVME_CMBSZ_SQS)) {
1951 		result = nvme_cmb_qdepth(dev, nr_io_queues,
1952 				sizeof(struct nvme_command));
1953 		if (result > 0)
1954 			dev->q_depth = result;
1955 		else
1956 			nvme_release_cmb(dev);
1957 	}
1958 
1959 	do {
1960 		size = db_bar_size(dev, nr_io_queues);
1961 		result = nvme_remap_bar(dev, size);
1962 		if (!result)
1963 			break;
1964 		if (!--nr_io_queues)
1965 			return -ENOMEM;
1966 	} while (1);
1967 	adminq->q_db = dev->dbs;
1968 
1969 	/* Deregister the admin queue's interrupt */
1970 	pci_free_irq(pdev, 0, adminq);
1971 
1972 	/*
1973 	 * If we enable msix early due to not intx, disable it again before
1974 	 * setting up the full range we need.
1975 	 */
1976 	pci_free_irq_vectors(pdev);
1977 	result = pci_alloc_irq_vectors_affinity(pdev, 1, nr_io_queues + 1,
1978 			PCI_IRQ_ALL_TYPES | PCI_IRQ_AFFINITY, &affd);
1979 	if (result <= 0)
1980 		return -EIO;
1981 	dev->num_vecs = result;
1982 	dev->max_qid = max(result - 1, 1);
1983 
1984 	/*
1985 	 * Should investigate if there's a performance win from allocating
1986 	 * more queues than interrupt vectors; it might allow the submission
1987 	 * path to scale better, even if the receive path is limited by the
1988 	 * number of interrupts.
1989 	 */
1990 
1991 	result = queue_request_irq(adminq);
1992 	if (result) {
1993 		adminq->cq_vector = -1;
1994 		return result;
1995 	}
1996 	return nvme_create_io_queues(dev);
1997 }
1998 
1999 static void nvme_del_queue_end(struct request *req, blk_status_t error)
2000 {
2001 	struct nvme_queue *nvmeq = req->end_io_data;
2002 
2003 	blk_mq_free_request(req);
2004 	complete(&nvmeq->dev->ioq_wait);
2005 }
2006 
2007 static void nvme_del_cq_end(struct request *req, blk_status_t error)
2008 {
2009 	struct nvme_queue *nvmeq = req->end_io_data;
2010 	u16 start, end;
2011 
2012 	if (!error) {
2013 		unsigned long flags;
2014 
2015 		/*
2016 		 * We might be called with the AQ cq_lock held
2017 		 * and the I/O queue cq_lock should always
2018 		 * nest inside the AQ one.
2019 		 */
2020 		spin_lock_irqsave_nested(&nvmeq->cq_lock, flags,
2021 					SINGLE_DEPTH_NESTING);
2022 		nvme_process_cq(nvmeq, &start, &end, -1);
2023 		spin_unlock_irqrestore(&nvmeq->cq_lock, flags);
2024 
2025 		nvme_complete_cqes(nvmeq, start, end);
2026 	}
2027 
2028 	nvme_del_queue_end(req, error);
2029 }
2030 
2031 static int nvme_delete_queue(struct nvme_queue *nvmeq, u8 opcode)
2032 {
2033 	struct request_queue *q = nvmeq->dev->ctrl.admin_q;
2034 	struct request *req;
2035 	struct nvme_command cmd;
2036 
2037 	memset(&cmd, 0, sizeof(cmd));
2038 	cmd.delete_queue.opcode = opcode;
2039 	cmd.delete_queue.qid = cpu_to_le16(nvmeq->qid);
2040 
2041 	req = nvme_alloc_request(q, &cmd, BLK_MQ_REQ_NOWAIT, NVME_QID_ANY);
2042 	if (IS_ERR(req))
2043 		return PTR_ERR(req);
2044 
2045 	req->timeout = ADMIN_TIMEOUT;
2046 	req->end_io_data = nvmeq;
2047 
2048 	blk_execute_rq_nowait(q, NULL, req, false,
2049 			opcode == nvme_admin_delete_cq ?
2050 				nvme_del_cq_end : nvme_del_queue_end);
2051 	return 0;
2052 }
2053 
2054 static void nvme_disable_io_queues(struct nvme_dev *dev)
2055 {
2056 	int pass, queues = dev->online_queues - 1;
2057 	unsigned long timeout;
2058 	u8 opcode = nvme_admin_delete_sq;
2059 
2060 	for (pass = 0; pass < 2; pass++) {
2061 		int sent = 0, i = queues;
2062 
2063 		reinit_completion(&dev->ioq_wait);
2064  retry:
2065 		timeout = ADMIN_TIMEOUT;
2066 		for (; i > 0; i--, sent++)
2067 			if (nvme_delete_queue(&dev->queues[i], opcode))
2068 				break;
2069 
2070 		while (sent--) {
2071 			timeout = wait_for_completion_io_timeout(&dev->ioq_wait, timeout);
2072 			if (timeout == 0)
2073 				return;
2074 			if (i)
2075 				goto retry;
2076 		}
2077 		opcode = nvme_admin_delete_cq;
2078 	}
2079 }
2080 
2081 /*
2082  * return error value only when tagset allocation failed
2083  */
2084 static int nvme_dev_add(struct nvme_dev *dev)
2085 {
2086 	int ret;
2087 
2088 	if (!dev->ctrl.tagset) {
2089 		dev->tagset.ops = &nvme_mq_ops;
2090 		dev->tagset.nr_hw_queues = dev->online_queues - 1;
2091 		dev->tagset.timeout = NVME_IO_TIMEOUT;
2092 		dev->tagset.numa_node = dev_to_node(dev->dev);
2093 		dev->tagset.queue_depth =
2094 				min_t(int, dev->q_depth, BLK_MQ_MAX_DEPTH) - 1;
2095 		dev->tagset.cmd_size = nvme_pci_cmd_size(dev, false);
2096 		if ((dev->ctrl.sgls & ((1 << 0) | (1 << 1))) && sgl_threshold) {
2097 			dev->tagset.cmd_size = max(dev->tagset.cmd_size,
2098 					nvme_pci_cmd_size(dev, true));
2099 		}
2100 		dev->tagset.flags = BLK_MQ_F_SHOULD_MERGE;
2101 		dev->tagset.driver_data = dev;
2102 
2103 		ret = blk_mq_alloc_tag_set(&dev->tagset);
2104 		if (ret) {
2105 			dev_warn(dev->ctrl.device,
2106 				"IO queues tagset allocation failed %d\n", ret);
2107 			return ret;
2108 		}
2109 		dev->ctrl.tagset = &dev->tagset;
2110 
2111 		nvme_dbbuf_set(dev);
2112 	} else {
2113 		blk_mq_update_nr_hw_queues(&dev->tagset, dev->online_queues - 1);
2114 
2115 		/* Free previously allocated queues that are no longer usable */
2116 		nvme_free_queues(dev, dev->online_queues);
2117 	}
2118 
2119 	return 0;
2120 }
2121 
2122 static int nvme_pci_enable(struct nvme_dev *dev)
2123 {
2124 	int result = -ENOMEM;
2125 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2126 
2127 	if (pci_enable_device_mem(pdev))
2128 		return result;
2129 
2130 	pci_set_master(pdev);
2131 
2132 	if (dma_set_mask_and_coherent(dev->dev, DMA_BIT_MASK(64)) &&
2133 	    dma_set_mask_and_coherent(dev->dev, DMA_BIT_MASK(32)))
2134 		goto disable;
2135 
2136 	if (readl(dev->bar + NVME_REG_CSTS) == -1) {
2137 		result = -ENODEV;
2138 		goto disable;
2139 	}
2140 
2141 	/*
2142 	 * Some devices and/or platforms don't advertise or work with INTx
2143 	 * interrupts. Pre-enable a single MSIX or MSI vec for setup. We'll
2144 	 * adjust this later.
2145 	 */
2146 	result = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
2147 	if (result < 0)
2148 		return result;
2149 
2150 	dev->ctrl.cap = lo_hi_readq(dev->bar + NVME_REG_CAP);
2151 
2152 	dev->q_depth = min_t(int, NVME_CAP_MQES(dev->ctrl.cap) + 1,
2153 				io_queue_depth);
2154 	dev->db_stride = 1 << NVME_CAP_STRIDE(dev->ctrl.cap);
2155 	dev->dbs = dev->bar + 4096;
2156 
2157 	/*
2158 	 * Temporary fix for the Apple controller found in the MacBook8,1 and
2159 	 * some MacBook7,1 to avoid controller resets and data loss.
2160 	 */
2161 	if (pdev->vendor == PCI_VENDOR_ID_APPLE && pdev->device == 0x2001) {
2162 		dev->q_depth = 2;
2163 		dev_warn(dev->ctrl.device, "detected Apple NVMe controller, "
2164 			"set queue depth=%u to work around controller resets\n",
2165 			dev->q_depth);
2166 	} else if (pdev->vendor == PCI_VENDOR_ID_SAMSUNG &&
2167 		   (pdev->device == 0xa821 || pdev->device == 0xa822) &&
2168 		   NVME_CAP_MQES(dev->ctrl.cap) == 0) {
2169 		dev->q_depth = 64;
2170 		dev_err(dev->ctrl.device, "detected PM1725 NVMe controller, "
2171                         "set queue depth=%u\n", dev->q_depth);
2172 	}
2173 
2174 	nvme_map_cmb(dev);
2175 
2176 	pci_enable_pcie_error_reporting(pdev);
2177 	pci_save_state(pdev);
2178 	return 0;
2179 
2180  disable:
2181 	pci_disable_device(pdev);
2182 	return result;
2183 }
2184 
2185 static void nvme_dev_unmap(struct nvme_dev *dev)
2186 {
2187 	if (dev->bar)
2188 		iounmap(dev->bar);
2189 	pci_release_mem_regions(to_pci_dev(dev->dev));
2190 }
2191 
2192 static void nvme_pci_disable(struct nvme_dev *dev)
2193 {
2194 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2195 
2196 	nvme_release_cmb(dev);
2197 	pci_free_irq_vectors(pdev);
2198 
2199 	if (pci_is_enabled(pdev)) {
2200 		pci_disable_pcie_error_reporting(pdev);
2201 		pci_disable_device(pdev);
2202 	}
2203 }
2204 
2205 static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown)
2206 {
2207 	int i;
2208 	bool dead = true;
2209 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2210 
2211 	mutex_lock(&dev->shutdown_lock);
2212 	if (pci_is_enabled(pdev)) {
2213 		u32 csts = readl(dev->bar + NVME_REG_CSTS);
2214 
2215 		if (dev->ctrl.state == NVME_CTRL_LIVE ||
2216 		    dev->ctrl.state == NVME_CTRL_RESETTING)
2217 			nvme_start_freeze(&dev->ctrl);
2218 		dead = !!((csts & NVME_CSTS_CFS) || !(csts & NVME_CSTS_RDY) ||
2219 			pdev->error_state  != pci_channel_io_normal);
2220 	}
2221 
2222 	/*
2223 	 * Give the controller a chance to complete all entered requests if
2224 	 * doing a safe shutdown.
2225 	 */
2226 	if (!dead) {
2227 		if (shutdown)
2228 			nvme_wait_freeze_timeout(&dev->ctrl, NVME_IO_TIMEOUT);
2229 	}
2230 
2231 	nvme_stop_queues(&dev->ctrl);
2232 
2233 	if (!dead && dev->ctrl.queue_count > 0) {
2234 		/*
2235 		 * If the controller is still alive tell it to stop using the
2236 		 * host memory buffer.  In theory the shutdown / reset should
2237 		 * make sure that it doesn't access the host memoery anymore,
2238 		 * but I'd rather be safe than sorry..
2239 		 */
2240 		if (dev->host_mem_descs)
2241 			nvme_set_host_mem(dev, 0);
2242 		nvme_disable_io_queues(dev);
2243 		nvme_disable_admin_queue(dev, shutdown);
2244 	}
2245 	for (i = dev->ctrl.queue_count - 1; i >= 0; i--)
2246 		nvme_suspend_queue(&dev->queues[i]);
2247 
2248 	nvme_pci_disable(dev);
2249 
2250 	blk_mq_tagset_busy_iter(&dev->tagset, nvme_cancel_request, &dev->ctrl);
2251 	blk_mq_tagset_busy_iter(&dev->admin_tagset, nvme_cancel_request, &dev->ctrl);
2252 
2253 	/*
2254 	 * The driver will not be starting up queues again if shutting down so
2255 	 * must flush all entered requests to their failed completion to avoid
2256 	 * deadlocking blk-mq hot-cpu notifier.
2257 	 */
2258 	if (shutdown)
2259 		nvme_start_queues(&dev->ctrl);
2260 	mutex_unlock(&dev->shutdown_lock);
2261 }
2262 
2263 static int nvme_setup_prp_pools(struct nvme_dev *dev)
2264 {
2265 	dev->prp_page_pool = dma_pool_create("prp list page", dev->dev,
2266 						PAGE_SIZE, PAGE_SIZE, 0);
2267 	if (!dev->prp_page_pool)
2268 		return -ENOMEM;
2269 
2270 	/* Optimisation for I/Os between 4k and 128k */
2271 	dev->prp_small_pool = dma_pool_create("prp list 256", dev->dev,
2272 						256, 256, 0);
2273 	if (!dev->prp_small_pool) {
2274 		dma_pool_destroy(dev->prp_page_pool);
2275 		return -ENOMEM;
2276 	}
2277 	return 0;
2278 }
2279 
2280 static void nvme_release_prp_pools(struct nvme_dev *dev)
2281 {
2282 	dma_pool_destroy(dev->prp_page_pool);
2283 	dma_pool_destroy(dev->prp_small_pool);
2284 }
2285 
2286 static void nvme_pci_free_ctrl(struct nvme_ctrl *ctrl)
2287 {
2288 	struct nvme_dev *dev = to_nvme_dev(ctrl);
2289 
2290 	nvme_dbbuf_dma_free(dev);
2291 	put_device(dev->dev);
2292 	if (dev->tagset.tags)
2293 		blk_mq_free_tag_set(&dev->tagset);
2294 	if (dev->ctrl.admin_q)
2295 		blk_put_queue(dev->ctrl.admin_q);
2296 	kfree(dev->queues);
2297 	free_opal_dev(dev->ctrl.opal_dev);
2298 	kfree(dev);
2299 }
2300 
2301 static void nvme_remove_dead_ctrl(struct nvme_dev *dev, int status)
2302 {
2303 	dev_warn(dev->ctrl.device, "Removing after probe failure status: %d\n", status);
2304 
2305 	nvme_get_ctrl(&dev->ctrl);
2306 	nvme_dev_disable(dev, false);
2307 	if (!queue_work(nvme_wq, &dev->remove_work))
2308 		nvme_put_ctrl(&dev->ctrl);
2309 }
2310 
2311 static void nvme_reset_work(struct work_struct *work)
2312 {
2313 	struct nvme_dev *dev =
2314 		container_of(work, struct nvme_dev, ctrl.reset_work);
2315 	bool was_suspend = !!(dev->ctrl.ctrl_config & NVME_CC_SHN_NORMAL);
2316 	int result = -ENODEV;
2317 	enum nvme_ctrl_state new_state = NVME_CTRL_LIVE;
2318 
2319 	if (WARN_ON(dev->ctrl.state != NVME_CTRL_RESETTING))
2320 		goto out;
2321 
2322 	/*
2323 	 * If we're called to reset a live controller first shut it down before
2324 	 * moving on.
2325 	 */
2326 	if (dev->ctrl.ctrl_config & NVME_CC_ENABLE)
2327 		nvme_dev_disable(dev, false);
2328 
2329 	/*
2330 	 * Introduce CONNECTING state from nvme-fc/rdma transports to mark the
2331 	 * initializing procedure here.
2332 	 */
2333 	if (!nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_CONNECTING)) {
2334 		dev_warn(dev->ctrl.device,
2335 			"failed to mark controller CONNECTING\n");
2336 		goto out;
2337 	}
2338 
2339 	result = nvme_pci_enable(dev);
2340 	if (result)
2341 		goto out;
2342 
2343 	result = nvme_pci_configure_admin_queue(dev);
2344 	if (result)
2345 		goto out;
2346 
2347 	result = nvme_alloc_admin_tags(dev);
2348 	if (result)
2349 		goto out;
2350 
2351 	result = nvme_init_identify(&dev->ctrl);
2352 	if (result)
2353 		goto out;
2354 
2355 	if (dev->ctrl.oacs & NVME_CTRL_OACS_SEC_SUPP) {
2356 		if (!dev->ctrl.opal_dev)
2357 			dev->ctrl.opal_dev =
2358 				init_opal_dev(&dev->ctrl, &nvme_sec_submit);
2359 		else if (was_suspend)
2360 			opal_unlock_from_suspend(dev->ctrl.opal_dev);
2361 	} else {
2362 		free_opal_dev(dev->ctrl.opal_dev);
2363 		dev->ctrl.opal_dev = NULL;
2364 	}
2365 
2366 	if (dev->ctrl.oacs & NVME_CTRL_OACS_DBBUF_SUPP) {
2367 		result = nvme_dbbuf_dma_alloc(dev);
2368 		if (result)
2369 			dev_warn(dev->dev,
2370 				 "unable to allocate dma for dbbuf\n");
2371 	}
2372 
2373 	if (dev->ctrl.hmpre) {
2374 		result = nvme_setup_host_mem(dev);
2375 		if (result < 0)
2376 			goto out;
2377 	}
2378 
2379 	result = nvme_setup_io_queues(dev);
2380 	if (result)
2381 		goto out;
2382 
2383 	/*
2384 	 * Keep the controller around but remove all namespaces if we don't have
2385 	 * any working I/O queue.
2386 	 */
2387 	if (dev->online_queues < 2) {
2388 		dev_warn(dev->ctrl.device, "IO queues not created\n");
2389 		nvme_kill_queues(&dev->ctrl);
2390 		nvme_remove_namespaces(&dev->ctrl);
2391 		new_state = NVME_CTRL_ADMIN_ONLY;
2392 	} else {
2393 		nvme_start_queues(&dev->ctrl);
2394 		nvme_wait_freeze(&dev->ctrl);
2395 		/* hit this only when allocate tagset fails */
2396 		if (nvme_dev_add(dev))
2397 			new_state = NVME_CTRL_ADMIN_ONLY;
2398 		nvme_unfreeze(&dev->ctrl);
2399 	}
2400 
2401 	/*
2402 	 * If only admin queue live, keep it to do further investigation or
2403 	 * recovery.
2404 	 */
2405 	if (!nvme_change_ctrl_state(&dev->ctrl, new_state)) {
2406 		dev_warn(dev->ctrl.device,
2407 			"failed to mark controller state %d\n", new_state);
2408 		goto out;
2409 	}
2410 
2411 	nvme_start_ctrl(&dev->ctrl);
2412 	return;
2413 
2414  out:
2415 	nvme_remove_dead_ctrl(dev, result);
2416 }
2417 
2418 static void nvme_remove_dead_ctrl_work(struct work_struct *work)
2419 {
2420 	struct nvme_dev *dev = container_of(work, struct nvme_dev, remove_work);
2421 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2422 
2423 	nvme_kill_queues(&dev->ctrl);
2424 	if (pci_get_drvdata(pdev))
2425 		device_release_driver(&pdev->dev);
2426 	nvme_put_ctrl(&dev->ctrl);
2427 }
2428 
2429 static int nvme_pci_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val)
2430 {
2431 	*val = readl(to_nvme_dev(ctrl)->bar + off);
2432 	return 0;
2433 }
2434 
2435 static int nvme_pci_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val)
2436 {
2437 	writel(val, to_nvme_dev(ctrl)->bar + off);
2438 	return 0;
2439 }
2440 
2441 static int nvme_pci_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val)
2442 {
2443 	*val = readq(to_nvme_dev(ctrl)->bar + off);
2444 	return 0;
2445 }
2446 
2447 static int nvme_pci_get_address(struct nvme_ctrl *ctrl, char *buf, int size)
2448 {
2449 	struct pci_dev *pdev = to_pci_dev(to_nvme_dev(ctrl)->dev);
2450 
2451 	return snprintf(buf, size, "%s", dev_name(&pdev->dev));
2452 }
2453 
2454 static const struct nvme_ctrl_ops nvme_pci_ctrl_ops = {
2455 	.name			= "pcie",
2456 	.module			= THIS_MODULE,
2457 	.flags			= NVME_F_METADATA_SUPPORTED,
2458 	.reg_read32		= nvme_pci_reg_read32,
2459 	.reg_write32		= nvme_pci_reg_write32,
2460 	.reg_read64		= nvme_pci_reg_read64,
2461 	.free_ctrl		= nvme_pci_free_ctrl,
2462 	.submit_async_event	= nvme_pci_submit_async_event,
2463 	.get_address		= nvme_pci_get_address,
2464 };
2465 
2466 static int nvme_dev_map(struct nvme_dev *dev)
2467 {
2468 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2469 
2470 	if (pci_request_mem_regions(pdev, "nvme"))
2471 		return -ENODEV;
2472 
2473 	if (nvme_remap_bar(dev, NVME_REG_DBS + 4096))
2474 		goto release;
2475 
2476 	return 0;
2477   release:
2478 	pci_release_mem_regions(pdev);
2479 	return -ENODEV;
2480 }
2481 
2482 static unsigned long check_vendor_combination_bug(struct pci_dev *pdev)
2483 {
2484 	if (pdev->vendor == 0x144d && pdev->device == 0xa802) {
2485 		/*
2486 		 * Several Samsung devices seem to drop off the PCIe bus
2487 		 * randomly when APST is on and uses the deepest sleep state.
2488 		 * This has been observed on a Samsung "SM951 NVMe SAMSUNG
2489 		 * 256GB", a "PM951 NVMe SAMSUNG 512GB", and a "Samsung SSD
2490 		 * 950 PRO 256GB", but it seems to be restricted to two Dell
2491 		 * laptops.
2492 		 */
2493 		if (dmi_match(DMI_SYS_VENDOR, "Dell Inc.") &&
2494 		    (dmi_match(DMI_PRODUCT_NAME, "XPS 15 9550") ||
2495 		     dmi_match(DMI_PRODUCT_NAME, "Precision 5510")))
2496 			return NVME_QUIRK_NO_DEEPEST_PS;
2497 	} else if (pdev->vendor == 0x144d && pdev->device == 0xa804) {
2498 		/*
2499 		 * Samsung SSD 960 EVO drops off the PCIe bus after system
2500 		 * suspend on a Ryzen board, ASUS PRIME B350M-A, as well as
2501 		 * within few minutes after bootup on a Coffee Lake board -
2502 		 * ASUS PRIME Z370-A
2503 		 */
2504 		if (dmi_match(DMI_BOARD_VENDOR, "ASUSTeK COMPUTER INC.") &&
2505 		    (dmi_match(DMI_BOARD_NAME, "PRIME B350M-A") ||
2506 		     dmi_match(DMI_BOARD_NAME, "PRIME Z370-A")))
2507 			return NVME_QUIRK_NO_APST;
2508 	}
2509 
2510 	return 0;
2511 }
2512 
2513 static void nvme_async_probe(void *data, async_cookie_t cookie)
2514 {
2515 	struct nvme_dev *dev = data;
2516 
2517 	nvme_reset_ctrl_sync(&dev->ctrl);
2518 	flush_work(&dev->ctrl.scan_work);
2519 	nvme_put_ctrl(&dev->ctrl);
2520 }
2521 
2522 static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
2523 {
2524 	int node, result = -ENOMEM;
2525 	struct nvme_dev *dev;
2526 	unsigned long quirks = id->driver_data;
2527 
2528 	node = dev_to_node(&pdev->dev);
2529 	if (node == NUMA_NO_NODE)
2530 		set_dev_node(&pdev->dev, first_memory_node);
2531 
2532 	dev = kzalloc_node(sizeof(*dev), GFP_KERNEL, node);
2533 	if (!dev)
2534 		return -ENOMEM;
2535 
2536 	dev->queues = kcalloc_node(num_possible_cpus() + 1,
2537 			sizeof(struct nvme_queue), GFP_KERNEL, node);
2538 	if (!dev->queues)
2539 		goto free;
2540 
2541 	dev->dev = get_device(&pdev->dev);
2542 	pci_set_drvdata(pdev, dev);
2543 
2544 	result = nvme_dev_map(dev);
2545 	if (result)
2546 		goto put_pci;
2547 
2548 	INIT_WORK(&dev->ctrl.reset_work, nvme_reset_work);
2549 	INIT_WORK(&dev->remove_work, nvme_remove_dead_ctrl_work);
2550 	mutex_init(&dev->shutdown_lock);
2551 	init_completion(&dev->ioq_wait);
2552 
2553 	result = nvme_setup_prp_pools(dev);
2554 	if (result)
2555 		goto unmap;
2556 
2557 	quirks |= check_vendor_combination_bug(pdev);
2558 
2559 	result = nvme_init_ctrl(&dev->ctrl, &pdev->dev, &nvme_pci_ctrl_ops,
2560 			quirks);
2561 	if (result)
2562 		goto release_pools;
2563 
2564 	dev_info(dev->ctrl.device, "pci function %s\n", dev_name(&pdev->dev));
2565 
2566 	nvme_get_ctrl(&dev->ctrl);
2567 	async_schedule(nvme_async_probe, dev);
2568 
2569 	return 0;
2570 
2571  release_pools:
2572 	nvme_release_prp_pools(dev);
2573  unmap:
2574 	nvme_dev_unmap(dev);
2575  put_pci:
2576 	put_device(dev->dev);
2577  free:
2578 	kfree(dev->queues);
2579 	kfree(dev);
2580 	return result;
2581 }
2582 
2583 static void nvme_reset_prepare(struct pci_dev *pdev)
2584 {
2585 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2586 	nvme_dev_disable(dev, false);
2587 }
2588 
2589 static void nvme_reset_done(struct pci_dev *pdev)
2590 {
2591 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2592 	nvme_reset_ctrl_sync(&dev->ctrl);
2593 }
2594 
2595 static void nvme_shutdown(struct pci_dev *pdev)
2596 {
2597 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2598 	nvme_dev_disable(dev, true);
2599 }
2600 
2601 /*
2602  * The driver's remove may be called on a device in a partially initialized
2603  * state. This function must not have any dependencies on the device state in
2604  * order to proceed.
2605  */
2606 static void nvme_remove(struct pci_dev *pdev)
2607 {
2608 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2609 
2610 	nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DELETING);
2611 
2612 	cancel_work_sync(&dev->ctrl.reset_work);
2613 	pci_set_drvdata(pdev, NULL);
2614 
2615 	if (!pci_device_is_present(pdev)) {
2616 		nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DEAD);
2617 		nvme_dev_disable(dev, false);
2618 	}
2619 
2620 	flush_work(&dev->ctrl.reset_work);
2621 	nvme_stop_ctrl(&dev->ctrl);
2622 	nvme_remove_namespaces(&dev->ctrl);
2623 	nvme_dev_disable(dev, true);
2624 	nvme_free_host_mem(dev);
2625 	nvme_dev_remove_admin(dev);
2626 	nvme_free_queues(dev, 0);
2627 	nvme_uninit_ctrl(&dev->ctrl);
2628 	nvme_release_prp_pools(dev);
2629 	nvme_dev_unmap(dev);
2630 	nvme_put_ctrl(&dev->ctrl);
2631 }
2632 
2633 static int nvme_pci_sriov_configure(struct pci_dev *pdev, int numvfs)
2634 {
2635 	int ret = 0;
2636 
2637 	if (numvfs == 0) {
2638 		if (pci_vfs_assigned(pdev)) {
2639 			dev_warn(&pdev->dev,
2640 				"Cannot disable SR-IOV VFs while assigned\n");
2641 			return -EPERM;
2642 		}
2643 		pci_disable_sriov(pdev);
2644 		return 0;
2645 	}
2646 
2647 	ret = pci_enable_sriov(pdev, numvfs);
2648 	return ret ? ret : numvfs;
2649 }
2650 
2651 #ifdef CONFIG_PM_SLEEP
2652 static int nvme_suspend(struct device *dev)
2653 {
2654 	struct pci_dev *pdev = to_pci_dev(dev);
2655 	struct nvme_dev *ndev = pci_get_drvdata(pdev);
2656 
2657 	nvme_dev_disable(ndev, true);
2658 	return 0;
2659 }
2660 
2661 static int nvme_resume(struct device *dev)
2662 {
2663 	struct pci_dev *pdev = to_pci_dev(dev);
2664 	struct nvme_dev *ndev = pci_get_drvdata(pdev);
2665 
2666 	nvme_reset_ctrl(&ndev->ctrl);
2667 	return 0;
2668 }
2669 #endif
2670 
2671 static SIMPLE_DEV_PM_OPS(nvme_dev_pm_ops, nvme_suspend, nvme_resume);
2672 
2673 static pci_ers_result_t nvme_error_detected(struct pci_dev *pdev,
2674 						pci_channel_state_t state)
2675 {
2676 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2677 
2678 	/*
2679 	 * A frozen channel requires a reset. When detected, this method will
2680 	 * shutdown the controller to quiesce. The controller will be restarted
2681 	 * after the slot reset through driver's slot_reset callback.
2682 	 */
2683 	switch (state) {
2684 	case pci_channel_io_normal:
2685 		return PCI_ERS_RESULT_CAN_RECOVER;
2686 	case pci_channel_io_frozen:
2687 		dev_warn(dev->ctrl.device,
2688 			"frozen state error detected, reset controller\n");
2689 		nvme_dev_disable(dev, false);
2690 		return PCI_ERS_RESULT_NEED_RESET;
2691 	case pci_channel_io_perm_failure:
2692 		dev_warn(dev->ctrl.device,
2693 			"failure state error detected, request disconnect\n");
2694 		return PCI_ERS_RESULT_DISCONNECT;
2695 	}
2696 	return PCI_ERS_RESULT_NEED_RESET;
2697 }
2698 
2699 static pci_ers_result_t nvme_slot_reset(struct pci_dev *pdev)
2700 {
2701 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2702 
2703 	dev_info(dev->ctrl.device, "restart after slot reset\n");
2704 	pci_restore_state(pdev);
2705 	nvme_reset_ctrl(&dev->ctrl);
2706 	return PCI_ERS_RESULT_RECOVERED;
2707 }
2708 
2709 static void nvme_error_resume(struct pci_dev *pdev)
2710 {
2711 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2712 
2713 	flush_work(&dev->ctrl.reset_work);
2714 	pci_cleanup_aer_uncorrect_error_status(pdev);
2715 }
2716 
2717 static const struct pci_error_handlers nvme_err_handler = {
2718 	.error_detected	= nvme_error_detected,
2719 	.slot_reset	= nvme_slot_reset,
2720 	.resume		= nvme_error_resume,
2721 	.reset_prepare	= nvme_reset_prepare,
2722 	.reset_done	= nvme_reset_done,
2723 };
2724 
2725 static const struct pci_device_id nvme_id_table[] = {
2726 	{ PCI_VDEVICE(INTEL, 0x0953),
2727 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
2728 				NVME_QUIRK_DEALLOCATE_ZEROES, },
2729 	{ PCI_VDEVICE(INTEL, 0x0a53),
2730 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
2731 				NVME_QUIRK_DEALLOCATE_ZEROES, },
2732 	{ PCI_VDEVICE(INTEL, 0x0a54),
2733 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
2734 				NVME_QUIRK_DEALLOCATE_ZEROES, },
2735 	{ PCI_VDEVICE(INTEL, 0x0a55),
2736 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
2737 				NVME_QUIRK_DEALLOCATE_ZEROES, },
2738 	{ PCI_VDEVICE(INTEL, 0xf1a5),	/* Intel 600P/P3100 */
2739 		.driver_data = NVME_QUIRK_NO_DEEPEST_PS |
2740 				NVME_QUIRK_MEDIUM_PRIO_SQ },
2741 	{ PCI_VDEVICE(INTEL, 0x5845),	/* Qemu emulated controller */
2742 		.driver_data = NVME_QUIRK_IDENTIFY_CNS, },
2743 	{ PCI_DEVICE(0x1bb1, 0x0100),   /* Seagate Nytro Flash Storage */
2744 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2745 	{ PCI_DEVICE(0x1c58, 0x0003),	/* HGST adapter */
2746 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2747 	{ PCI_DEVICE(0x1c58, 0x0023),	/* WDC SN200 adapter */
2748 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2749 	{ PCI_DEVICE(0x1c5f, 0x0540),	/* Memblaze Pblaze4 adapter */
2750 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2751 	{ PCI_DEVICE(0x144d, 0xa821),   /* Samsung PM1725 */
2752 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2753 	{ PCI_DEVICE(0x144d, 0xa822),   /* Samsung PM1725a */
2754 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2755 	{ PCI_DEVICE(0x1d1d, 0x1f1f),	/* LighNVM qemu device */
2756 		.driver_data = NVME_QUIRK_LIGHTNVM, },
2757 	{ PCI_DEVICE(0x1d1d, 0x2807),	/* CNEX WL */
2758 		.driver_data = NVME_QUIRK_LIGHTNVM, },
2759 	{ PCI_DEVICE(0x1d1d, 0x2601),	/* CNEX Granby */
2760 		.driver_data = NVME_QUIRK_LIGHTNVM, },
2761 	{ PCI_DEVICE_CLASS(PCI_CLASS_STORAGE_EXPRESS, 0xffffff) },
2762 	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2001) },
2763 	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2003) },
2764 	{ 0, }
2765 };
2766 MODULE_DEVICE_TABLE(pci, nvme_id_table);
2767 
2768 static struct pci_driver nvme_driver = {
2769 	.name		= "nvme",
2770 	.id_table	= nvme_id_table,
2771 	.probe		= nvme_probe,
2772 	.remove		= nvme_remove,
2773 	.shutdown	= nvme_shutdown,
2774 	.driver		= {
2775 		.pm	= &nvme_dev_pm_ops,
2776 	},
2777 	.sriov_configure = nvme_pci_sriov_configure,
2778 	.err_handler	= &nvme_err_handler,
2779 };
2780 
2781 static int __init nvme_init(void)
2782 {
2783 	return pci_register_driver(&nvme_driver);
2784 }
2785 
2786 static void __exit nvme_exit(void)
2787 {
2788 	pci_unregister_driver(&nvme_driver);
2789 	flush_workqueue(nvme_wq);
2790 	_nvme_check_size();
2791 }
2792 
2793 MODULE_AUTHOR("Matthew Wilcox <willy@linux.intel.com>");
2794 MODULE_LICENSE("GPL");
2795 MODULE_VERSION("1.0");
2796 module_init(nvme_init);
2797 module_exit(nvme_exit);
2798