xref: /openbmc/linux/drivers/nvme/host/pci.c (revision 6396bb221514d2876fd6dc0aa2a1f240d99b37bb)
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, 0444);
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 (nvme_dbbuf_update_and_check_event(head, nvmeq->dbbuf_cq_db,
924 					      nvmeq->dbbuf_cq_ei))
925 		writel(head, nvmeq->q_db + nvmeq->dev->db_stride);
926 }
927 
928 static inline void nvme_handle_cqe(struct nvme_queue *nvmeq, u16 idx)
929 {
930 	volatile struct nvme_completion *cqe = &nvmeq->cqes[idx];
931 	struct request *req;
932 
933 	if (unlikely(cqe->command_id >= nvmeq->q_depth)) {
934 		dev_warn(nvmeq->dev->ctrl.device,
935 			"invalid id %d completed on queue %d\n",
936 			cqe->command_id, le16_to_cpu(cqe->sq_id));
937 		return;
938 	}
939 
940 	/*
941 	 * AEN requests are special as they don't time out and can
942 	 * survive any kind of queue freeze and often don't respond to
943 	 * aborts.  We don't even bother to allocate a struct request
944 	 * for them but rather special case them here.
945 	 */
946 	if (unlikely(nvmeq->qid == 0 &&
947 			cqe->command_id >= NVME_AQ_BLK_MQ_DEPTH)) {
948 		nvme_complete_async_event(&nvmeq->dev->ctrl,
949 				cqe->status, &cqe->result);
950 		return;
951 	}
952 
953 	req = blk_mq_tag_to_rq(*nvmeq->tags, cqe->command_id);
954 	nvme_end_request(req, cqe->status, cqe->result);
955 }
956 
957 static void nvme_complete_cqes(struct nvme_queue *nvmeq, u16 start, u16 end)
958 {
959 	while (start != end) {
960 		nvme_handle_cqe(nvmeq, start);
961 		if (++start == nvmeq->q_depth)
962 			start = 0;
963 	}
964 }
965 
966 static inline void nvme_update_cq_head(struct nvme_queue *nvmeq)
967 {
968 	if (++nvmeq->cq_head == nvmeq->q_depth) {
969 		nvmeq->cq_head = 0;
970 		nvmeq->cq_phase = !nvmeq->cq_phase;
971 	}
972 }
973 
974 static inline bool nvme_process_cq(struct nvme_queue *nvmeq, u16 *start,
975 		u16 *end, int tag)
976 {
977 	bool found = false;
978 
979 	*start = nvmeq->cq_head;
980 	while (!found && nvme_cqe_pending(nvmeq)) {
981 		if (nvmeq->cqes[nvmeq->cq_head].command_id == tag)
982 			found = true;
983 		nvme_update_cq_head(nvmeq);
984 	}
985 	*end = nvmeq->cq_head;
986 
987 	if (*start != *end)
988 		nvme_ring_cq_doorbell(nvmeq);
989 	return found;
990 }
991 
992 static irqreturn_t nvme_irq(int irq, void *data)
993 {
994 	struct nvme_queue *nvmeq = data;
995 	irqreturn_t ret = IRQ_NONE;
996 	u16 start, end;
997 
998 	spin_lock(&nvmeq->cq_lock);
999 	if (nvmeq->cq_head != nvmeq->last_cq_head)
1000 		ret = IRQ_HANDLED;
1001 	nvme_process_cq(nvmeq, &start, &end, -1);
1002 	nvmeq->last_cq_head = nvmeq->cq_head;
1003 	spin_unlock(&nvmeq->cq_lock);
1004 
1005 	if (start != end) {
1006 		nvme_complete_cqes(nvmeq, start, end);
1007 		return IRQ_HANDLED;
1008 	}
1009 
1010 	return ret;
1011 }
1012 
1013 static irqreturn_t nvme_irq_check(int irq, void *data)
1014 {
1015 	struct nvme_queue *nvmeq = data;
1016 	if (nvme_cqe_pending(nvmeq))
1017 		return IRQ_WAKE_THREAD;
1018 	return IRQ_NONE;
1019 }
1020 
1021 static int __nvme_poll(struct nvme_queue *nvmeq, unsigned int tag)
1022 {
1023 	u16 start, end;
1024 	bool found;
1025 
1026 	if (!nvme_cqe_pending(nvmeq))
1027 		return 0;
1028 
1029 	spin_lock_irq(&nvmeq->cq_lock);
1030 	found = nvme_process_cq(nvmeq, &start, &end, tag);
1031 	spin_unlock_irq(&nvmeq->cq_lock);
1032 
1033 	nvme_complete_cqes(nvmeq, start, end);
1034 	return found;
1035 }
1036 
1037 static int nvme_poll(struct blk_mq_hw_ctx *hctx, unsigned int tag)
1038 {
1039 	struct nvme_queue *nvmeq = hctx->driver_data;
1040 
1041 	return __nvme_poll(nvmeq, tag);
1042 }
1043 
1044 static void nvme_pci_submit_async_event(struct nvme_ctrl *ctrl)
1045 {
1046 	struct nvme_dev *dev = to_nvme_dev(ctrl);
1047 	struct nvme_queue *nvmeq = &dev->queues[0];
1048 	struct nvme_command c;
1049 
1050 	memset(&c, 0, sizeof(c));
1051 	c.common.opcode = nvme_admin_async_event;
1052 	c.common.command_id = NVME_AQ_BLK_MQ_DEPTH;
1053 	nvme_submit_cmd(nvmeq, &c);
1054 }
1055 
1056 static int adapter_delete_queue(struct nvme_dev *dev, u8 opcode, u16 id)
1057 {
1058 	struct nvme_command c;
1059 
1060 	memset(&c, 0, sizeof(c));
1061 	c.delete_queue.opcode = opcode;
1062 	c.delete_queue.qid = cpu_to_le16(id);
1063 
1064 	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1065 }
1066 
1067 static int adapter_alloc_cq(struct nvme_dev *dev, u16 qid,
1068 		struct nvme_queue *nvmeq, s16 vector)
1069 {
1070 	struct nvme_command c;
1071 	int flags = NVME_QUEUE_PHYS_CONTIG | NVME_CQ_IRQ_ENABLED;
1072 
1073 	/*
1074 	 * Note: we (ab)use the fact that the prp fields survive if no data
1075 	 * is attached to the request.
1076 	 */
1077 	memset(&c, 0, sizeof(c));
1078 	c.create_cq.opcode = nvme_admin_create_cq;
1079 	c.create_cq.prp1 = cpu_to_le64(nvmeq->cq_dma_addr);
1080 	c.create_cq.cqid = cpu_to_le16(qid);
1081 	c.create_cq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
1082 	c.create_cq.cq_flags = cpu_to_le16(flags);
1083 	c.create_cq.irq_vector = cpu_to_le16(vector);
1084 
1085 	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1086 }
1087 
1088 static int adapter_alloc_sq(struct nvme_dev *dev, u16 qid,
1089 						struct nvme_queue *nvmeq)
1090 {
1091 	struct nvme_ctrl *ctrl = &dev->ctrl;
1092 	struct nvme_command c;
1093 	int flags = NVME_QUEUE_PHYS_CONTIG;
1094 
1095 	/*
1096 	 * Some drives have a bug that auto-enables WRRU if MEDIUM isn't
1097 	 * set. Since URGENT priority is zeroes, it makes all queues
1098 	 * URGENT.
1099 	 */
1100 	if (ctrl->quirks & NVME_QUIRK_MEDIUM_PRIO_SQ)
1101 		flags |= NVME_SQ_PRIO_MEDIUM;
1102 
1103 	/*
1104 	 * Note: we (ab)use the fact that the prp fields survive if no data
1105 	 * is attached to the request.
1106 	 */
1107 	memset(&c, 0, sizeof(c));
1108 	c.create_sq.opcode = nvme_admin_create_sq;
1109 	c.create_sq.prp1 = cpu_to_le64(nvmeq->sq_dma_addr);
1110 	c.create_sq.sqid = cpu_to_le16(qid);
1111 	c.create_sq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
1112 	c.create_sq.sq_flags = cpu_to_le16(flags);
1113 	c.create_sq.cqid = cpu_to_le16(qid);
1114 
1115 	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1116 }
1117 
1118 static int adapter_delete_cq(struct nvme_dev *dev, u16 cqid)
1119 {
1120 	return adapter_delete_queue(dev, nvme_admin_delete_cq, cqid);
1121 }
1122 
1123 static int adapter_delete_sq(struct nvme_dev *dev, u16 sqid)
1124 {
1125 	return adapter_delete_queue(dev, nvme_admin_delete_sq, sqid);
1126 }
1127 
1128 static void abort_endio(struct request *req, blk_status_t error)
1129 {
1130 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
1131 	struct nvme_queue *nvmeq = iod->nvmeq;
1132 
1133 	dev_warn(nvmeq->dev->ctrl.device,
1134 		 "Abort status: 0x%x", nvme_req(req)->status);
1135 	atomic_inc(&nvmeq->dev->ctrl.abort_limit);
1136 	blk_mq_free_request(req);
1137 }
1138 
1139 static bool nvme_should_reset(struct nvme_dev *dev, u32 csts)
1140 {
1141 
1142 	/* If true, indicates loss of adapter communication, possibly by a
1143 	 * NVMe Subsystem reset.
1144 	 */
1145 	bool nssro = dev->subsystem && (csts & NVME_CSTS_NSSRO);
1146 
1147 	/* If there is a reset/reinit ongoing, we shouldn't reset again. */
1148 	switch (dev->ctrl.state) {
1149 	case NVME_CTRL_RESETTING:
1150 	case NVME_CTRL_CONNECTING:
1151 		return false;
1152 	default:
1153 		break;
1154 	}
1155 
1156 	/* We shouldn't reset unless the controller is on fatal error state
1157 	 * _or_ if we lost the communication with it.
1158 	 */
1159 	if (!(csts & NVME_CSTS_CFS) && !nssro)
1160 		return false;
1161 
1162 	return true;
1163 }
1164 
1165 static void nvme_warn_reset(struct nvme_dev *dev, u32 csts)
1166 {
1167 	/* Read a config register to help see what died. */
1168 	u16 pci_status;
1169 	int result;
1170 
1171 	result = pci_read_config_word(to_pci_dev(dev->dev), PCI_STATUS,
1172 				      &pci_status);
1173 	if (result == PCIBIOS_SUCCESSFUL)
1174 		dev_warn(dev->ctrl.device,
1175 			 "controller is down; will reset: CSTS=0x%x, PCI_STATUS=0x%hx\n",
1176 			 csts, pci_status);
1177 	else
1178 		dev_warn(dev->ctrl.device,
1179 			 "controller is down; will reset: CSTS=0x%x, PCI_STATUS read failed (%d)\n",
1180 			 csts, result);
1181 }
1182 
1183 static enum blk_eh_timer_return nvme_timeout(struct request *req, bool reserved)
1184 {
1185 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
1186 	struct nvme_queue *nvmeq = iod->nvmeq;
1187 	struct nvme_dev *dev = nvmeq->dev;
1188 	struct request *abort_req;
1189 	struct nvme_command cmd;
1190 	u32 csts = readl(dev->bar + NVME_REG_CSTS);
1191 
1192 	/* If PCI error recovery process is happening, we cannot reset or
1193 	 * the recovery mechanism will surely fail.
1194 	 */
1195 	mb();
1196 	if (pci_channel_offline(to_pci_dev(dev->dev)))
1197 		return BLK_EH_RESET_TIMER;
1198 
1199 	/*
1200 	 * Reset immediately if the controller is failed
1201 	 */
1202 	if (nvme_should_reset(dev, csts)) {
1203 		nvme_warn_reset(dev, csts);
1204 		nvme_dev_disable(dev, false);
1205 		nvme_reset_ctrl(&dev->ctrl);
1206 		return BLK_EH_DONE;
1207 	}
1208 
1209 	/*
1210 	 * Did we miss an interrupt?
1211 	 */
1212 	if (__nvme_poll(nvmeq, req->tag)) {
1213 		dev_warn(dev->ctrl.device,
1214 			 "I/O %d QID %d timeout, completion polled\n",
1215 			 req->tag, nvmeq->qid);
1216 		return BLK_EH_DONE;
1217 	}
1218 
1219 	/*
1220 	 * Shutdown immediately if controller times out while starting. The
1221 	 * reset work will see the pci device disabled when it gets the forced
1222 	 * cancellation error. All outstanding requests are completed on
1223 	 * shutdown, so we return BLK_EH_DONE.
1224 	 */
1225 	switch (dev->ctrl.state) {
1226 	case NVME_CTRL_CONNECTING:
1227 	case NVME_CTRL_RESETTING:
1228 		dev_warn_ratelimited(dev->ctrl.device,
1229 			 "I/O %d QID %d timeout, disable controller\n",
1230 			 req->tag, nvmeq->qid);
1231 		nvme_dev_disable(dev, false);
1232 		nvme_req(req)->flags |= NVME_REQ_CANCELLED;
1233 		return BLK_EH_DONE;
1234 	default:
1235 		break;
1236 	}
1237 
1238 	/*
1239  	 * Shutdown the controller immediately and schedule a reset if the
1240  	 * command was already aborted once before and still hasn't been
1241  	 * returned to the driver, or if this is the admin queue.
1242 	 */
1243 	if (!nvmeq->qid || iod->aborted) {
1244 		dev_warn(dev->ctrl.device,
1245 			 "I/O %d QID %d timeout, reset controller\n",
1246 			 req->tag, nvmeq->qid);
1247 		nvme_dev_disable(dev, false);
1248 		nvme_reset_ctrl(&dev->ctrl);
1249 
1250 		nvme_req(req)->flags |= NVME_REQ_CANCELLED;
1251 		return BLK_EH_DONE;
1252 	}
1253 
1254 	if (atomic_dec_return(&dev->ctrl.abort_limit) < 0) {
1255 		atomic_inc(&dev->ctrl.abort_limit);
1256 		return BLK_EH_RESET_TIMER;
1257 	}
1258 	iod->aborted = 1;
1259 
1260 	memset(&cmd, 0, sizeof(cmd));
1261 	cmd.abort.opcode = nvme_admin_abort_cmd;
1262 	cmd.abort.cid = req->tag;
1263 	cmd.abort.sqid = cpu_to_le16(nvmeq->qid);
1264 
1265 	dev_warn(nvmeq->dev->ctrl.device,
1266 		"I/O %d QID %d timeout, aborting\n",
1267 		 req->tag, nvmeq->qid);
1268 
1269 	abort_req = nvme_alloc_request(dev->ctrl.admin_q, &cmd,
1270 			BLK_MQ_REQ_NOWAIT, NVME_QID_ANY);
1271 	if (IS_ERR(abort_req)) {
1272 		atomic_inc(&dev->ctrl.abort_limit);
1273 		return BLK_EH_RESET_TIMER;
1274 	}
1275 
1276 	abort_req->timeout = ADMIN_TIMEOUT;
1277 	abort_req->end_io_data = NULL;
1278 	blk_execute_rq_nowait(abort_req->q, NULL, abort_req, 0, abort_endio);
1279 
1280 	/*
1281 	 * The aborted req will be completed on receiving the abort req.
1282 	 * We enable the timer again. If hit twice, it'll cause a device reset,
1283 	 * as the device then is in a faulty state.
1284 	 */
1285 	return BLK_EH_RESET_TIMER;
1286 }
1287 
1288 static void nvme_free_queue(struct nvme_queue *nvmeq)
1289 {
1290 	dma_free_coherent(nvmeq->q_dmadev, CQ_SIZE(nvmeq->q_depth),
1291 				(void *)nvmeq->cqes, nvmeq->cq_dma_addr);
1292 	if (nvmeq->sq_cmds)
1293 		dma_free_coherent(nvmeq->q_dmadev, SQ_SIZE(nvmeq->q_depth),
1294 					nvmeq->sq_cmds, nvmeq->sq_dma_addr);
1295 }
1296 
1297 static void nvme_free_queues(struct nvme_dev *dev, int lowest)
1298 {
1299 	int i;
1300 
1301 	for (i = dev->ctrl.queue_count - 1; i >= lowest; i--) {
1302 		dev->ctrl.queue_count--;
1303 		nvme_free_queue(&dev->queues[i]);
1304 	}
1305 }
1306 
1307 /**
1308  * nvme_suspend_queue - put queue into suspended state
1309  * @nvmeq - queue to suspend
1310  */
1311 static int nvme_suspend_queue(struct nvme_queue *nvmeq)
1312 {
1313 	int vector;
1314 
1315 	spin_lock_irq(&nvmeq->cq_lock);
1316 	if (nvmeq->cq_vector == -1) {
1317 		spin_unlock_irq(&nvmeq->cq_lock);
1318 		return 1;
1319 	}
1320 	vector = nvmeq->cq_vector;
1321 	nvmeq->dev->online_queues--;
1322 	nvmeq->cq_vector = -1;
1323 	spin_unlock_irq(&nvmeq->cq_lock);
1324 
1325 	/*
1326 	 * Ensure that nvme_queue_rq() sees it ->cq_vector == -1 without
1327 	 * having to grab the lock.
1328 	 */
1329 	mb();
1330 
1331 	if (!nvmeq->qid && nvmeq->dev->ctrl.admin_q)
1332 		blk_mq_quiesce_queue(nvmeq->dev->ctrl.admin_q);
1333 
1334 	pci_free_irq(to_pci_dev(nvmeq->dev->dev), vector, nvmeq);
1335 
1336 	return 0;
1337 }
1338 
1339 static void nvme_disable_admin_queue(struct nvme_dev *dev, bool shutdown)
1340 {
1341 	struct nvme_queue *nvmeq = &dev->queues[0];
1342 	u16 start, end;
1343 
1344 	if (shutdown)
1345 		nvme_shutdown_ctrl(&dev->ctrl);
1346 	else
1347 		nvme_disable_ctrl(&dev->ctrl, dev->ctrl.cap);
1348 
1349 	spin_lock_irq(&nvmeq->cq_lock);
1350 	nvme_process_cq(nvmeq, &start, &end, -1);
1351 	spin_unlock_irq(&nvmeq->cq_lock);
1352 
1353 	nvme_complete_cqes(nvmeq, start, end);
1354 }
1355 
1356 static int nvme_cmb_qdepth(struct nvme_dev *dev, int nr_io_queues,
1357 				int entry_size)
1358 {
1359 	int q_depth = dev->q_depth;
1360 	unsigned q_size_aligned = roundup(q_depth * entry_size,
1361 					  dev->ctrl.page_size);
1362 
1363 	if (q_size_aligned * nr_io_queues > dev->cmb_size) {
1364 		u64 mem_per_q = div_u64(dev->cmb_size, nr_io_queues);
1365 		mem_per_q = round_down(mem_per_q, dev->ctrl.page_size);
1366 		q_depth = div_u64(mem_per_q, entry_size);
1367 
1368 		/*
1369 		 * Ensure the reduced q_depth is above some threshold where it
1370 		 * would be better to map queues in system memory with the
1371 		 * original depth
1372 		 */
1373 		if (q_depth < 64)
1374 			return -ENOMEM;
1375 	}
1376 
1377 	return q_depth;
1378 }
1379 
1380 static int nvme_alloc_sq_cmds(struct nvme_dev *dev, struct nvme_queue *nvmeq,
1381 				int qid, int depth)
1382 {
1383 	/* CMB SQEs will be mapped before creation */
1384 	if (qid && dev->cmb && use_cmb_sqes && (dev->cmbsz & NVME_CMBSZ_SQS))
1385 		return 0;
1386 
1387 	nvmeq->sq_cmds = dma_alloc_coherent(dev->dev, SQ_SIZE(depth),
1388 					    &nvmeq->sq_dma_addr, GFP_KERNEL);
1389 	if (!nvmeq->sq_cmds)
1390 		return -ENOMEM;
1391 	return 0;
1392 }
1393 
1394 static int nvme_alloc_queue(struct nvme_dev *dev, int qid, int depth)
1395 {
1396 	struct nvme_queue *nvmeq = &dev->queues[qid];
1397 
1398 	if (dev->ctrl.queue_count > qid)
1399 		return 0;
1400 
1401 	nvmeq->cqes = dma_zalloc_coherent(dev->dev, CQ_SIZE(depth),
1402 					  &nvmeq->cq_dma_addr, GFP_KERNEL);
1403 	if (!nvmeq->cqes)
1404 		goto free_nvmeq;
1405 
1406 	if (nvme_alloc_sq_cmds(dev, nvmeq, qid, depth))
1407 		goto free_cqdma;
1408 
1409 	nvmeq->q_dmadev = dev->dev;
1410 	nvmeq->dev = dev;
1411 	spin_lock_init(&nvmeq->sq_lock);
1412 	spin_lock_init(&nvmeq->cq_lock);
1413 	nvmeq->cq_head = 0;
1414 	nvmeq->cq_phase = 1;
1415 	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
1416 	nvmeq->q_depth = depth;
1417 	nvmeq->qid = qid;
1418 	nvmeq->cq_vector = -1;
1419 	dev->ctrl.queue_count++;
1420 
1421 	return 0;
1422 
1423  free_cqdma:
1424 	dma_free_coherent(dev->dev, CQ_SIZE(depth), (void *)nvmeq->cqes,
1425 							nvmeq->cq_dma_addr);
1426  free_nvmeq:
1427 	return -ENOMEM;
1428 }
1429 
1430 static int queue_request_irq(struct nvme_queue *nvmeq)
1431 {
1432 	struct pci_dev *pdev = to_pci_dev(nvmeq->dev->dev);
1433 	int nr = nvmeq->dev->ctrl.instance;
1434 
1435 	if (use_threaded_interrupts) {
1436 		return pci_request_irq(pdev, nvmeq->cq_vector, nvme_irq_check,
1437 				nvme_irq, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
1438 	} else {
1439 		return pci_request_irq(pdev, nvmeq->cq_vector, nvme_irq,
1440 				NULL, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
1441 	}
1442 }
1443 
1444 static void nvme_init_queue(struct nvme_queue *nvmeq, u16 qid)
1445 {
1446 	struct nvme_dev *dev = nvmeq->dev;
1447 
1448 	spin_lock_irq(&nvmeq->cq_lock);
1449 	nvmeq->sq_tail = 0;
1450 	nvmeq->cq_head = 0;
1451 	nvmeq->cq_phase = 1;
1452 	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
1453 	memset((void *)nvmeq->cqes, 0, CQ_SIZE(nvmeq->q_depth));
1454 	nvme_dbbuf_init(dev, nvmeq, qid);
1455 	dev->online_queues++;
1456 	spin_unlock_irq(&nvmeq->cq_lock);
1457 }
1458 
1459 static int nvme_create_queue(struct nvme_queue *nvmeq, int qid)
1460 {
1461 	struct nvme_dev *dev = nvmeq->dev;
1462 	int result;
1463 	s16 vector;
1464 
1465 	if (dev->cmb && use_cmb_sqes && (dev->cmbsz & NVME_CMBSZ_SQS)) {
1466 		unsigned offset = (qid - 1) * roundup(SQ_SIZE(nvmeq->q_depth),
1467 						      dev->ctrl.page_size);
1468 		nvmeq->sq_dma_addr = dev->cmb_bus_addr + offset;
1469 		nvmeq->sq_cmds_io = dev->cmb + offset;
1470 	}
1471 
1472 	/*
1473 	 * A queue's vector matches the queue identifier unless the controller
1474 	 * has only one vector available.
1475 	 */
1476 	vector = dev->num_vecs == 1 ? 0 : qid;
1477 	result = adapter_alloc_cq(dev, qid, nvmeq, vector);
1478 	if (result)
1479 		return result;
1480 
1481 	result = adapter_alloc_sq(dev, qid, nvmeq);
1482 	if (result < 0)
1483 		return result;
1484 	else if (result)
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 	return result;
1507 }
1508 
1509 static const struct blk_mq_ops nvme_mq_admin_ops = {
1510 	.queue_rq	= nvme_queue_rq,
1511 	.complete	= nvme_pci_complete_rq,
1512 	.init_hctx	= nvme_admin_init_hctx,
1513 	.exit_hctx      = nvme_admin_exit_hctx,
1514 	.init_request	= nvme_init_request,
1515 	.timeout	= nvme_timeout,
1516 };
1517 
1518 static const struct blk_mq_ops nvme_mq_ops = {
1519 	.queue_rq	= nvme_queue_rq,
1520 	.complete	= nvme_pci_complete_rq,
1521 	.init_hctx	= nvme_init_hctx,
1522 	.init_request	= nvme_init_request,
1523 	.map_queues	= nvme_pci_map_queues,
1524 	.timeout	= nvme_timeout,
1525 	.poll		= nvme_poll,
1526 };
1527 
1528 static void nvme_dev_remove_admin(struct nvme_dev *dev)
1529 {
1530 	if (dev->ctrl.admin_q && !blk_queue_dying(dev->ctrl.admin_q)) {
1531 		/*
1532 		 * If the controller was reset during removal, it's possible
1533 		 * user requests may be waiting on a stopped queue. Start the
1534 		 * queue to flush these to completion.
1535 		 */
1536 		blk_mq_unquiesce_queue(dev->ctrl.admin_q);
1537 		blk_cleanup_queue(dev->ctrl.admin_q);
1538 		blk_mq_free_tag_set(&dev->admin_tagset);
1539 	}
1540 }
1541 
1542 static int nvme_alloc_admin_tags(struct nvme_dev *dev)
1543 {
1544 	if (!dev->ctrl.admin_q) {
1545 		dev->admin_tagset.ops = &nvme_mq_admin_ops;
1546 		dev->admin_tagset.nr_hw_queues = 1;
1547 
1548 		dev->admin_tagset.queue_depth = NVME_AQ_MQ_TAG_DEPTH;
1549 		dev->admin_tagset.timeout = ADMIN_TIMEOUT;
1550 		dev->admin_tagset.numa_node = dev_to_node(dev->dev);
1551 		dev->admin_tagset.cmd_size = nvme_pci_cmd_size(dev, false);
1552 		dev->admin_tagset.flags = BLK_MQ_F_NO_SCHED;
1553 		dev->admin_tagset.driver_data = dev;
1554 
1555 		if (blk_mq_alloc_tag_set(&dev->admin_tagset))
1556 			return -ENOMEM;
1557 		dev->ctrl.admin_tagset = &dev->admin_tagset;
1558 
1559 		dev->ctrl.admin_q = blk_mq_init_queue(&dev->admin_tagset);
1560 		if (IS_ERR(dev->ctrl.admin_q)) {
1561 			blk_mq_free_tag_set(&dev->admin_tagset);
1562 			return -ENOMEM;
1563 		}
1564 		if (!blk_get_queue(dev->ctrl.admin_q)) {
1565 			nvme_dev_remove_admin(dev);
1566 			dev->ctrl.admin_q = NULL;
1567 			return -ENODEV;
1568 		}
1569 	} else
1570 		blk_mq_unquiesce_queue(dev->ctrl.admin_q);
1571 
1572 	return 0;
1573 }
1574 
1575 static unsigned long db_bar_size(struct nvme_dev *dev, unsigned nr_io_queues)
1576 {
1577 	return NVME_REG_DBS + ((nr_io_queues + 1) * 8 * dev->db_stride);
1578 }
1579 
1580 static int nvme_remap_bar(struct nvme_dev *dev, unsigned long size)
1581 {
1582 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1583 
1584 	if (size <= dev->bar_mapped_size)
1585 		return 0;
1586 	if (size > pci_resource_len(pdev, 0))
1587 		return -ENOMEM;
1588 	if (dev->bar)
1589 		iounmap(dev->bar);
1590 	dev->bar = ioremap(pci_resource_start(pdev, 0), size);
1591 	if (!dev->bar) {
1592 		dev->bar_mapped_size = 0;
1593 		return -ENOMEM;
1594 	}
1595 	dev->bar_mapped_size = size;
1596 	dev->dbs = dev->bar + NVME_REG_DBS;
1597 
1598 	return 0;
1599 }
1600 
1601 static int nvme_pci_configure_admin_queue(struct nvme_dev *dev)
1602 {
1603 	int result;
1604 	u32 aqa;
1605 	struct nvme_queue *nvmeq;
1606 
1607 	result = nvme_remap_bar(dev, db_bar_size(dev, 0));
1608 	if (result < 0)
1609 		return result;
1610 
1611 	dev->subsystem = readl(dev->bar + NVME_REG_VS) >= NVME_VS(1, 1, 0) ?
1612 				NVME_CAP_NSSRC(dev->ctrl.cap) : 0;
1613 
1614 	if (dev->subsystem &&
1615 	    (readl(dev->bar + NVME_REG_CSTS) & NVME_CSTS_NSSRO))
1616 		writel(NVME_CSTS_NSSRO, dev->bar + NVME_REG_CSTS);
1617 
1618 	result = nvme_disable_ctrl(&dev->ctrl, dev->ctrl.cap);
1619 	if (result < 0)
1620 		return result;
1621 
1622 	result = nvme_alloc_queue(dev, 0, NVME_AQ_DEPTH);
1623 	if (result)
1624 		return result;
1625 
1626 	nvmeq = &dev->queues[0];
1627 	aqa = nvmeq->q_depth - 1;
1628 	aqa |= aqa << 16;
1629 
1630 	writel(aqa, dev->bar + NVME_REG_AQA);
1631 	lo_hi_writeq(nvmeq->sq_dma_addr, dev->bar + NVME_REG_ASQ);
1632 	lo_hi_writeq(nvmeq->cq_dma_addr, dev->bar + NVME_REG_ACQ);
1633 
1634 	result = nvme_enable_ctrl(&dev->ctrl, dev->ctrl.cap);
1635 	if (result)
1636 		return result;
1637 
1638 	nvmeq->cq_vector = 0;
1639 	nvme_init_queue(nvmeq, 0);
1640 	result = queue_request_irq(nvmeq);
1641 	if (result) {
1642 		nvmeq->cq_vector = -1;
1643 		return result;
1644 	}
1645 
1646 	return result;
1647 }
1648 
1649 static int nvme_create_io_queues(struct nvme_dev *dev)
1650 {
1651 	unsigned i, max;
1652 	int ret = 0;
1653 
1654 	for (i = dev->ctrl.queue_count; i <= dev->max_qid; i++) {
1655 		if (nvme_alloc_queue(dev, i, dev->q_depth)) {
1656 			ret = -ENOMEM;
1657 			break;
1658 		}
1659 	}
1660 
1661 	max = min(dev->max_qid, dev->ctrl.queue_count - 1);
1662 	for (i = dev->online_queues; i <= max; i++) {
1663 		ret = nvme_create_queue(&dev->queues[i], i);
1664 		if (ret)
1665 			break;
1666 	}
1667 
1668 	/*
1669 	 * Ignore failing Create SQ/CQ commands, we can continue with less
1670 	 * than the desired amount of queues, and even a controller without
1671 	 * I/O queues can still be used to issue admin commands.  This might
1672 	 * be useful to upgrade a buggy firmware for example.
1673 	 */
1674 	return ret >= 0 ? 0 : ret;
1675 }
1676 
1677 static ssize_t nvme_cmb_show(struct device *dev,
1678 			     struct device_attribute *attr,
1679 			     char *buf)
1680 {
1681 	struct nvme_dev *ndev = to_nvme_dev(dev_get_drvdata(dev));
1682 
1683 	return scnprintf(buf, PAGE_SIZE, "cmbloc : x%08x\ncmbsz  : x%08x\n",
1684 		       ndev->cmbloc, ndev->cmbsz);
1685 }
1686 static DEVICE_ATTR(cmb, S_IRUGO, nvme_cmb_show, NULL);
1687 
1688 static u64 nvme_cmb_size_unit(struct nvme_dev *dev)
1689 {
1690 	u8 szu = (dev->cmbsz >> NVME_CMBSZ_SZU_SHIFT) & NVME_CMBSZ_SZU_MASK;
1691 
1692 	return 1ULL << (12 + 4 * szu);
1693 }
1694 
1695 static u32 nvme_cmb_size(struct nvme_dev *dev)
1696 {
1697 	return (dev->cmbsz >> NVME_CMBSZ_SZ_SHIFT) & NVME_CMBSZ_SZ_MASK;
1698 }
1699 
1700 static void nvme_map_cmb(struct nvme_dev *dev)
1701 {
1702 	u64 size, offset;
1703 	resource_size_t bar_size;
1704 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1705 	int bar;
1706 
1707 	dev->cmbsz = readl(dev->bar + NVME_REG_CMBSZ);
1708 	if (!dev->cmbsz)
1709 		return;
1710 	dev->cmbloc = readl(dev->bar + NVME_REG_CMBLOC);
1711 
1712 	if (!use_cmb_sqes)
1713 		return;
1714 
1715 	size = nvme_cmb_size_unit(dev) * nvme_cmb_size(dev);
1716 	offset = nvme_cmb_size_unit(dev) * NVME_CMB_OFST(dev->cmbloc);
1717 	bar = NVME_CMB_BIR(dev->cmbloc);
1718 	bar_size = pci_resource_len(pdev, bar);
1719 
1720 	if (offset > bar_size)
1721 		return;
1722 
1723 	/*
1724 	 * Controllers may support a CMB size larger than their BAR,
1725 	 * for example, due to being behind a bridge. Reduce the CMB to
1726 	 * the reported size of the BAR
1727 	 */
1728 	if (size > bar_size - offset)
1729 		size = bar_size - offset;
1730 
1731 	dev->cmb = ioremap_wc(pci_resource_start(pdev, bar) + offset, size);
1732 	if (!dev->cmb)
1733 		return;
1734 	dev->cmb_bus_addr = pci_bus_address(pdev, bar) + offset;
1735 	dev->cmb_size = size;
1736 
1737 	if (sysfs_add_file_to_group(&dev->ctrl.device->kobj,
1738 				    &dev_attr_cmb.attr, NULL))
1739 		dev_warn(dev->ctrl.device,
1740 			 "failed to add sysfs attribute for CMB\n");
1741 }
1742 
1743 static inline void nvme_release_cmb(struct nvme_dev *dev)
1744 {
1745 	if (dev->cmb) {
1746 		iounmap(dev->cmb);
1747 		dev->cmb = NULL;
1748 		sysfs_remove_file_from_group(&dev->ctrl.device->kobj,
1749 					     &dev_attr_cmb.attr, NULL);
1750 		dev->cmbsz = 0;
1751 	}
1752 }
1753 
1754 static int nvme_set_host_mem(struct nvme_dev *dev, u32 bits)
1755 {
1756 	u64 dma_addr = dev->host_mem_descs_dma;
1757 	struct nvme_command c;
1758 	int ret;
1759 
1760 	memset(&c, 0, sizeof(c));
1761 	c.features.opcode	= nvme_admin_set_features;
1762 	c.features.fid		= cpu_to_le32(NVME_FEAT_HOST_MEM_BUF);
1763 	c.features.dword11	= cpu_to_le32(bits);
1764 	c.features.dword12	= cpu_to_le32(dev->host_mem_size >>
1765 					      ilog2(dev->ctrl.page_size));
1766 	c.features.dword13	= cpu_to_le32(lower_32_bits(dma_addr));
1767 	c.features.dword14	= cpu_to_le32(upper_32_bits(dma_addr));
1768 	c.features.dword15	= cpu_to_le32(dev->nr_host_mem_descs);
1769 
1770 	ret = nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1771 	if (ret) {
1772 		dev_warn(dev->ctrl.device,
1773 			 "failed to set host mem (err %d, flags %#x).\n",
1774 			 ret, bits);
1775 	}
1776 	return ret;
1777 }
1778 
1779 static void nvme_free_host_mem(struct nvme_dev *dev)
1780 {
1781 	int i;
1782 
1783 	for (i = 0; i < dev->nr_host_mem_descs; i++) {
1784 		struct nvme_host_mem_buf_desc *desc = &dev->host_mem_descs[i];
1785 		size_t size = le32_to_cpu(desc->size) * dev->ctrl.page_size;
1786 
1787 		dma_free_coherent(dev->dev, size, dev->host_mem_desc_bufs[i],
1788 				le64_to_cpu(desc->addr));
1789 	}
1790 
1791 	kfree(dev->host_mem_desc_bufs);
1792 	dev->host_mem_desc_bufs = NULL;
1793 	dma_free_coherent(dev->dev,
1794 			dev->nr_host_mem_descs * sizeof(*dev->host_mem_descs),
1795 			dev->host_mem_descs, dev->host_mem_descs_dma);
1796 	dev->host_mem_descs = NULL;
1797 	dev->nr_host_mem_descs = 0;
1798 }
1799 
1800 static int __nvme_alloc_host_mem(struct nvme_dev *dev, u64 preferred,
1801 		u32 chunk_size)
1802 {
1803 	struct nvme_host_mem_buf_desc *descs;
1804 	u32 max_entries, len;
1805 	dma_addr_t descs_dma;
1806 	int i = 0;
1807 	void **bufs;
1808 	u64 size, tmp;
1809 
1810 	tmp = (preferred + chunk_size - 1);
1811 	do_div(tmp, chunk_size);
1812 	max_entries = tmp;
1813 
1814 	if (dev->ctrl.hmmaxd && dev->ctrl.hmmaxd < max_entries)
1815 		max_entries = dev->ctrl.hmmaxd;
1816 
1817 	descs = dma_zalloc_coherent(dev->dev, max_entries * sizeof(*descs),
1818 			&descs_dma, GFP_KERNEL);
1819 	if (!descs)
1820 		goto out;
1821 
1822 	bufs = kcalloc(max_entries, sizeof(*bufs), GFP_KERNEL);
1823 	if (!bufs)
1824 		goto out_free_descs;
1825 
1826 	for (size = 0; size < preferred && i < max_entries; size += len) {
1827 		dma_addr_t dma_addr;
1828 
1829 		len = min_t(u64, chunk_size, preferred - size);
1830 		bufs[i] = dma_alloc_attrs(dev->dev, len, &dma_addr, GFP_KERNEL,
1831 				DMA_ATTR_NO_KERNEL_MAPPING | DMA_ATTR_NO_WARN);
1832 		if (!bufs[i])
1833 			break;
1834 
1835 		descs[i].addr = cpu_to_le64(dma_addr);
1836 		descs[i].size = cpu_to_le32(len / dev->ctrl.page_size);
1837 		i++;
1838 	}
1839 
1840 	if (!size)
1841 		goto out_free_bufs;
1842 
1843 	dev->nr_host_mem_descs = i;
1844 	dev->host_mem_size = size;
1845 	dev->host_mem_descs = descs;
1846 	dev->host_mem_descs_dma = descs_dma;
1847 	dev->host_mem_desc_bufs = bufs;
1848 	return 0;
1849 
1850 out_free_bufs:
1851 	while (--i >= 0) {
1852 		size_t size = le32_to_cpu(descs[i].size) * dev->ctrl.page_size;
1853 
1854 		dma_free_coherent(dev->dev, size, bufs[i],
1855 				le64_to_cpu(descs[i].addr));
1856 	}
1857 
1858 	kfree(bufs);
1859 out_free_descs:
1860 	dma_free_coherent(dev->dev, max_entries * sizeof(*descs), descs,
1861 			descs_dma);
1862 out:
1863 	dev->host_mem_descs = NULL;
1864 	return -ENOMEM;
1865 }
1866 
1867 static int nvme_alloc_host_mem(struct nvme_dev *dev, u64 min, u64 preferred)
1868 {
1869 	u32 chunk_size;
1870 
1871 	/* start big and work our way down */
1872 	for (chunk_size = min_t(u64, preferred, PAGE_SIZE * MAX_ORDER_NR_PAGES);
1873 	     chunk_size >= max_t(u32, dev->ctrl.hmminds * 4096, PAGE_SIZE * 2);
1874 	     chunk_size /= 2) {
1875 		if (!__nvme_alloc_host_mem(dev, preferred, chunk_size)) {
1876 			if (!min || dev->host_mem_size >= min)
1877 				return 0;
1878 			nvme_free_host_mem(dev);
1879 		}
1880 	}
1881 
1882 	return -ENOMEM;
1883 }
1884 
1885 static int nvme_setup_host_mem(struct nvme_dev *dev)
1886 {
1887 	u64 max = (u64)max_host_mem_size_mb * SZ_1M;
1888 	u64 preferred = (u64)dev->ctrl.hmpre * 4096;
1889 	u64 min = (u64)dev->ctrl.hmmin * 4096;
1890 	u32 enable_bits = NVME_HOST_MEM_ENABLE;
1891 	int ret;
1892 
1893 	preferred = min(preferred, max);
1894 	if (min > max) {
1895 		dev_warn(dev->ctrl.device,
1896 			"min host memory (%lld MiB) above limit (%d MiB).\n",
1897 			min >> ilog2(SZ_1M), max_host_mem_size_mb);
1898 		nvme_free_host_mem(dev);
1899 		return 0;
1900 	}
1901 
1902 	/*
1903 	 * If we already have a buffer allocated check if we can reuse it.
1904 	 */
1905 	if (dev->host_mem_descs) {
1906 		if (dev->host_mem_size >= min)
1907 			enable_bits |= NVME_HOST_MEM_RETURN;
1908 		else
1909 			nvme_free_host_mem(dev);
1910 	}
1911 
1912 	if (!dev->host_mem_descs) {
1913 		if (nvme_alloc_host_mem(dev, min, preferred)) {
1914 			dev_warn(dev->ctrl.device,
1915 				"failed to allocate host memory buffer.\n");
1916 			return 0; /* controller must work without HMB */
1917 		}
1918 
1919 		dev_info(dev->ctrl.device,
1920 			"allocated %lld MiB host memory buffer.\n",
1921 			dev->host_mem_size >> ilog2(SZ_1M));
1922 	}
1923 
1924 	ret = nvme_set_host_mem(dev, enable_bits);
1925 	if (ret)
1926 		nvme_free_host_mem(dev);
1927 	return ret;
1928 }
1929 
1930 static int nvme_setup_io_queues(struct nvme_dev *dev)
1931 {
1932 	struct nvme_queue *adminq = &dev->queues[0];
1933 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1934 	int result, nr_io_queues;
1935 	unsigned long size;
1936 
1937 	struct irq_affinity affd = {
1938 		.pre_vectors = 1
1939 	};
1940 
1941 	nr_io_queues = num_possible_cpus();
1942 	result = nvme_set_queue_count(&dev->ctrl, &nr_io_queues);
1943 	if (result < 0)
1944 		return result;
1945 
1946 	if (nr_io_queues == 0)
1947 		return 0;
1948 
1949 	if (dev->cmb && (dev->cmbsz & NVME_CMBSZ_SQS)) {
1950 		result = nvme_cmb_qdepth(dev, nr_io_queues,
1951 				sizeof(struct nvme_command));
1952 		if (result > 0)
1953 			dev->q_depth = result;
1954 		else
1955 			nvme_release_cmb(dev);
1956 	}
1957 
1958 	do {
1959 		size = db_bar_size(dev, nr_io_queues);
1960 		result = nvme_remap_bar(dev, size);
1961 		if (!result)
1962 			break;
1963 		if (!--nr_io_queues)
1964 			return -ENOMEM;
1965 	} while (1);
1966 	adminq->q_db = dev->dbs;
1967 
1968 	/* Deregister the admin queue's interrupt */
1969 	pci_free_irq(pdev, 0, adminq);
1970 
1971 	/*
1972 	 * If we enable msix early due to not intx, disable it again before
1973 	 * setting up the full range we need.
1974 	 */
1975 	pci_free_irq_vectors(pdev);
1976 	result = pci_alloc_irq_vectors_affinity(pdev, 1, nr_io_queues + 1,
1977 			PCI_IRQ_ALL_TYPES | PCI_IRQ_AFFINITY, &affd);
1978 	if (result <= 0)
1979 		return -EIO;
1980 	dev->num_vecs = result;
1981 	dev->max_qid = max(result - 1, 1);
1982 
1983 	/*
1984 	 * Should investigate if there's a performance win from allocating
1985 	 * more queues than interrupt vectors; it might allow the submission
1986 	 * path to scale better, even if the receive path is limited by the
1987 	 * number of interrupts.
1988 	 */
1989 
1990 	result = queue_request_irq(adminq);
1991 	if (result) {
1992 		adminq->cq_vector = -1;
1993 		return result;
1994 	}
1995 	return nvme_create_io_queues(dev);
1996 }
1997 
1998 static void nvme_del_queue_end(struct request *req, blk_status_t error)
1999 {
2000 	struct nvme_queue *nvmeq = req->end_io_data;
2001 
2002 	blk_mq_free_request(req);
2003 	complete(&nvmeq->dev->ioq_wait);
2004 }
2005 
2006 static void nvme_del_cq_end(struct request *req, blk_status_t error)
2007 {
2008 	struct nvme_queue *nvmeq = req->end_io_data;
2009 	u16 start, end;
2010 
2011 	if (!error) {
2012 		unsigned long flags;
2013 
2014 		spin_lock_irqsave(&nvmeq->cq_lock, flags);
2015 		nvme_process_cq(nvmeq, &start, &end, -1);
2016 		spin_unlock_irqrestore(&nvmeq->cq_lock, flags);
2017 
2018 		nvme_complete_cqes(nvmeq, start, end);
2019 	}
2020 
2021 	nvme_del_queue_end(req, error);
2022 }
2023 
2024 static int nvme_delete_queue(struct nvme_queue *nvmeq, u8 opcode)
2025 {
2026 	struct request_queue *q = nvmeq->dev->ctrl.admin_q;
2027 	struct request *req;
2028 	struct nvme_command cmd;
2029 
2030 	memset(&cmd, 0, sizeof(cmd));
2031 	cmd.delete_queue.opcode = opcode;
2032 	cmd.delete_queue.qid = cpu_to_le16(nvmeq->qid);
2033 
2034 	req = nvme_alloc_request(q, &cmd, BLK_MQ_REQ_NOWAIT, NVME_QID_ANY);
2035 	if (IS_ERR(req))
2036 		return PTR_ERR(req);
2037 
2038 	req->timeout = ADMIN_TIMEOUT;
2039 	req->end_io_data = nvmeq;
2040 
2041 	blk_execute_rq_nowait(q, NULL, req, false,
2042 			opcode == nvme_admin_delete_cq ?
2043 				nvme_del_cq_end : nvme_del_queue_end);
2044 	return 0;
2045 }
2046 
2047 static void nvme_disable_io_queues(struct nvme_dev *dev)
2048 {
2049 	int pass, queues = dev->online_queues - 1;
2050 	unsigned long timeout;
2051 	u8 opcode = nvme_admin_delete_sq;
2052 
2053 	for (pass = 0; pass < 2; pass++) {
2054 		int sent = 0, i = queues;
2055 
2056 		reinit_completion(&dev->ioq_wait);
2057  retry:
2058 		timeout = ADMIN_TIMEOUT;
2059 		for (; i > 0; i--, sent++)
2060 			if (nvme_delete_queue(&dev->queues[i], opcode))
2061 				break;
2062 
2063 		while (sent--) {
2064 			timeout = wait_for_completion_io_timeout(&dev->ioq_wait, timeout);
2065 			if (timeout == 0)
2066 				return;
2067 			if (i)
2068 				goto retry;
2069 		}
2070 		opcode = nvme_admin_delete_cq;
2071 	}
2072 }
2073 
2074 /*
2075  * return error value only when tagset allocation failed
2076  */
2077 static int nvme_dev_add(struct nvme_dev *dev)
2078 {
2079 	int ret;
2080 
2081 	if (!dev->ctrl.tagset) {
2082 		dev->tagset.ops = &nvme_mq_ops;
2083 		dev->tagset.nr_hw_queues = dev->online_queues - 1;
2084 		dev->tagset.timeout = NVME_IO_TIMEOUT;
2085 		dev->tagset.numa_node = dev_to_node(dev->dev);
2086 		dev->tagset.queue_depth =
2087 				min_t(int, dev->q_depth, BLK_MQ_MAX_DEPTH) - 1;
2088 		dev->tagset.cmd_size = nvme_pci_cmd_size(dev, false);
2089 		if ((dev->ctrl.sgls & ((1 << 0) | (1 << 1))) && sgl_threshold) {
2090 			dev->tagset.cmd_size = max(dev->tagset.cmd_size,
2091 					nvme_pci_cmd_size(dev, true));
2092 		}
2093 		dev->tagset.flags = BLK_MQ_F_SHOULD_MERGE;
2094 		dev->tagset.driver_data = dev;
2095 
2096 		ret = blk_mq_alloc_tag_set(&dev->tagset);
2097 		if (ret) {
2098 			dev_warn(dev->ctrl.device,
2099 				"IO queues tagset allocation failed %d\n", ret);
2100 			return ret;
2101 		}
2102 		dev->ctrl.tagset = &dev->tagset;
2103 
2104 		nvme_dbbuf_set(dev);
2105 	} else {
2106 		blk_mq_update_nr_hw_queues(&dev->tagset, dev->online_queues - 1);
2107 
2108 		/* Free previously allocated queues that are no longer usable */
2109 		nvme_free_queues(dev, dev->online_queues);
2110 	}
2111 
2112 	return 0;
2113 }
2114 
2115 static int nvme_pci_enable(struct nvme_dev *dev)
2116 {
2117 	int result = -ENOMEM;
2118 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2119 
2120 	if (pci_enable_device_mem(pdev))
2121 		return result;
2122 
2123 	pci_set_master(pdev);
2124 
2125 	if (dma_set_mask_and_coherent(dev->dev, DMA_BIT_MASK(64)) &&
2126 	    dma_set_mask_and_coherent(dev->dev, DMA_BIT_MASK(32)))
2127 		goto disable;
2128 
2129 	if (readl(dev->bar + NVME_REG_CSTS) == -1) {
2130 		result = -ENODEV;
2131 		goto disable;
2132 	}
2133 
2134 	/*
2135 	 * Some devices and/or platforms don't advertise or work with INTx
2136 	 * interrupts. Pre-enable a single MSIX or MSI vec for setup. We'll
2137 	 * adjust this later.
2138 	 */
2139 	result = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
2140 	if (result < 0)
2141 		return result;
2142 
2143 	dev->ctrl.cap = lo_hi_readq(dev->bar + NVME_REG_CAP);
2144 
2145 	dev->q_depth = min_t(int, NVME_CAP_MQES(dev->ctrl.cap) + 1,
2146 				io_queue_depth);
2147 	dev->db_stride = 1 << NVME_CAP_STRIDE(dev->ctrl.cap);
2148 	dev->dbs = dev->bar + 4096;
2149 
2150 	/*
2151 	 * Temporary fix for the Apple controller found in the MacBook8,1 and
2152 	 * some MacBook7,1 to avoid controller resets and data loss.
2153 	 */
2154 	if (pdev->vendor == PCI_VENDOR_ID_APPLE && pdev->device == 0x2001) {
2155 		dev->q_depth = 2;
2156 		dev_warn(dev->ctrl.device, "detected Apple NVMe controller, "
2157 			"set queue depth=%u to work around controller resets\n",
2158 			dev->q_depth);
2159 	} else if (pdev->vendor == PCI_VENDOR_ID_SAMSUNG &&
2160 		   (pdev->device == 0xa821 || pdev->device == 0xa822) &&
2161 		   NVME_CAP_MQES(dev->ctrl.cap) == 0) {
2162 		dev->q_depth = 64;
2163 		dev_err(dev->ctrl.device, "detected PM1725 NVMe controller, "
2164                         "set queue depth=%u\n", dev->q_depth);
2165 	}
2166 
2167 	nvme_map_cmb(dev);
2168 
2169 	pci_enable_pcie_error_reporting(pdev);
2170 	pci_save_state(pdev);
2171 	return 0;
2172 
2173  disable:
2174 	pci_disable_device(pdev);
2175 	return result;
2176 }
2177 
2178 static void nvme_dev_unmap(struct nvme_dev *dev)
2179 {
2180 	if (dev->bar)
2181 		iounmap(dev->bar);
2182 	pci_release_mem_regions(to_pci_dev(dev->dev));
2183 }
2184 
2185 static void nvme_pci_disable(struct nvme_dev *dev)
2186 {
2187 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2188 
2189 	nvme_release_cmb(dev);
2190 	pci_free_irq_vectors(pdev);
2191 
2192 	if (pci_is_enabled(pdev)) {
2193 		pci_disable_pcie_error_reporting(pdev);
2194 		pci_disable_device(pdev);
2195 	}
2196 }
2197 
2198 static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown)
2199 {
2200 	int i;
2201 	bool dead = true;
2202 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2203 
2204 	mutex_lock(&dev->shutdown_lock);
2205 	if (pci_is_enabled(pdev)) {
2206 		u32 csts = readl(dev->bar + NVME_REG_CSTS);
2207 
2208 		if (dev->ctrl.state == NVME_CTRL_LIVE ||
2209 		    dev->ctrl.state == NVME_CTRL_RESETTING)
2210 			nvme_start_freeze(&dev->ctrl);
2211 		dead = !!((csts & NVME_CSTS_CFS) || !(csts & NVME_CSTS_RDY) ||
2212 			pdev->error_state  != pci_channel_io_normal);
2213 	}
2214 
2215 	/*
2216 	 * Give the controller a chance to complete all entered requests if
2217 	 * doing a safe shutdown.
2218 	 */
2219 	if (!dead) {
2220 		if (shutdown)
2221 			nvme_wait_freeze_timeout(&dev->ctrl, NVME_IO_TIMEOUT);
2222 	}
2223 
2224 	nvme_stop_queues(&dev->ctrl);
2225 
2226 	if (!dead && dev->ctrl.queue_count > 0) {
2227 		nvme_disable_io_queues(dev);
2228 		nvme_disable_admin_queue(dev, shutdown);
2229 	}
2230 	for (i = dev->ctrl.queue_count - 1; i >= 0; i--)
2231 		nvme_suspend_queue(&dev->queues[i]);
2232 
2233 	nvme_pci_disable(dev);
2234 
2235 	blk_mq_tagset_busy_iter(&dev->tagset, nvme_cancel_request, &dev->ctrl);
2236 	blk_mq_tagset_busy_iter(&dev->admin_tagset, nvme_cancel_request, &dev->ctrl);
2237 
2238 	/*
2239 	 * The driver will not be starting up queues again if shutting down so
2240 	 * must flush all entered requests to their failed completion to avoid
2241 	 * deadlocking blk-mq hot-cpu notifier.
2242 	 */
2243 	if (shutdown)
2244 		nvme_start_queues(&dev->ctrl);
2245 	mutex_unlock(&dev->shutdown_lock);
2246 }
2247 
2248 static int nvme_setup_prp_pools(struct nvme_dev *dev)
2249 {
2250 	dev->prp_page_pool = dma_pool_create("prp list page", dev->dev,
2251 						PAGE_SIZE, PAGE_SIZE, 0);
2252 	if (!dev->prp_page_pool)
2253 		return -ENOMEM;
2254 
2255 	/* Optimisation for I/Os between 4k and 128k */
2256 	dev->prp_small_pool = dma_pool_create("prp list 256", dev->dev,
2257 						256, 256, 0);
2258 	if (!dev->prp_small_pool) {
2259 		dma_pool_destroy(dev->prp_page_pool);
2260 		return -ENOMEM;
2261 	}
2262 	return 0;
2263 }
2264 
2265 static void nvme_release_prp_pools(struct nvme_dev *dev)
2266 {
2267 	dma_pool_destroy(dev->prp_page_pool);
2268 	dma_pool_destroy(dev->prp_small_pool);
2269 }
2270 
2271 static void nvme_pci_free_ctrl(struct nvme_ctrl *ctrl)
2272 {
2273 	struct nvme_dev *dev = to_nvme_dev(ctrl);
2274 
2275 	nvme_dbbuf_dma_free(dev);
2276 	put_device(dev->dev);
2277 	if (dev->tagset.tags)
2278 		blk_mq_free_tag_set(&dev->tagset);
2279 	if (dev->ctrl.admin_q)
2280 		blk_put_queue(dev->ctrl.admin_q);
2281 	kfree(dev->queues);
2282 	free_opal_dev(dev->ctrl.opal_dev);
2283 	kfree(dev);
2284 }
2285 
2286 static void nvme_remove_dead_ctrl(struct nvme_dev *dev, int status)
2287 {
2288 	dev_warn(dev->ctrl.device, "Removing after probe failure status: %d\n", status);
2289 
2290 	nvme_get_ctrl(&dev->ctrl);
2291 	nvme_dev_disable(dev, false);
2292 	if (!queue_work(nvme_wq, &dev->remove_work))
2293 		nvme_put_ctrl(&dev->ctrl);
2294 }
2295 
2296 static void nvme_reset_work(struct work_struct *work)
2297 {
2298 	struct nvme_dev *dev =
2299 		container_of(work, struct nvme_dev, ctrl.reset_work);
2300 	bool was_suspend = !!(dev->ctrl.ctrl_config & NVME_CC_SHN_NORMAL);
2301 	int result = -ENODEV;
2302 	enum nvme_ctrl_state new_state = NVME_CTRL_LIVE;
2303 
2304 	if (WARN_ON(dev->ctrl.state != NVME_CTRL_RESETTING))
2305 		goto out;
2306 
2307 	/*
2308 	 * If we're called to reset a live controller first shut it down before
2309 	 * moving on.
2310 	 */
2311 	if (dev->ctrl.ctrl_config & NVME_CC_ENABLE)
2312 		nvme_dev_disable(dev, false);
2313 
2314 	/*
2315 	 * Introduce CONNECTING state from nvme-fc/rdma transports to mark the
2316 	 * initializing procedure here.
2317 	 */
2318 	if (!nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_CONNECTING)) {
2319 		dev_warn(dev->ctrl.device,
2320 			"failed to mark controller CONNECTING\n");
2321 		goto out;
2322 	}
2323 
2324 	result = nvme_pci_enable(dev);
2325 	if (result)
2326 		goto out;
2327 
2328 	result = nvme_pci_configure_admin_queue(dev);
2329 	if (result)
2330 		goto out;
2331 
2332 	result = nvme_alloc_admin_tags(dev);
2333 	if (result)
2334 		goto out;
2335 
2336 	result = nvme_init_identify(&dev->ctrl);
2337 	if (result)
2338 		goto out;
2339 
2340 	if (dev->ctrl.oacs & NVME_CTRL_OACS_SEC_SUPP) {
2341 		if (!dev->ctrl.opal_dev)
2342 			dev->ctrl.opal_dev =
2343 				init_opal_dev(&dev->ctrl, &nvme_sec_submit);
2344 		else if (was_suspend)
2345 			opal_unlock_from_suspend(dev->ctrl.opal_dev);
2346 	} else {
2347 		free_opal_dev(dev->ctrl.opal_dev);
2348 		dev->ctrl.opal_dev = NULL;
2349 	}
2350 
2351 	if (dev->ctrl.oacs & NVME_CTRL_OACS_DBBUF_SUPP) {
2352 		result = nvme_dbbuf_dma_alloc(dev);
2353 		if (result)
2354 			dev_warn(dev->dev,
2355 				 "unable to allocate dma for dbbuf\n");
2356 	}
2357 
2358 	if (dev->ctrl.hmpre) {
2359 		result = nvme_setup_host_mem(dev);
2360 		if (result < 0)
2361 			goto out;
2362 	}
2363 
2364 	result = nvme_setup_io_queues(dev);
2365 	if (result)
2366 		goto out;
2367 
2368 	/*
2369 	 * Keep the controller around but remove all namespaces if we don't have
2370 	 * any working I/O queue.
2371 	 */
2372 	if (dev->online_queues < 2) {
2373 		dev_warn(dev->ctrl.device, "IO queues not created\n");
2374 		nvme_kill_queues(&dev->ctrl);
2375 		nvme_remove_namespaces(&dev->ctrl);
2376 		new_state = NVME_CTRL_ADMIN_ONLY;
2377 	} else {
2378 		nvme_start_queues(&dev->ctrl);
2379 		nvme_wait_freeze(&dev->ctrl);
2380 		/* hit this only when allocate tagset fails */
2381 		if (nvme_dev_add(dev))
2382 			new_state = NVME_CTRL_ADMIN_ONLY;
2383 		nvme_unfreeze(&dev->ctrl);
2384 	}
2385 
2386 	/*
2387 	 * If only admin queue live, keep it to do further investigation or
2388 	 * recovery.
2389 	 */
2390 	if (!nvme_change_ctrl_state(&dev->ctrl, new_state)) {
2391 		dev_warn(dev->ctrl.device,
2392 			"failed to mark controller state %d\n", new_state);
2393 		goto out;
2394 	}
2395 
2396 	nvme_start_ctrl(&dev->ctrl);
2397 	return;
2398 
2399  out:
2400 	nvme_remove_dead_ctrl(dev, result);
2401 }
2402 
2403 static void nvme_remove_dead_ctrl_work(struct work_struct *work)
2404 {
2405 	struct nvme_dev *dev = container_of(work, struct nvme_dev, remove_work);
2406 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2407 
2408 	nvme_kill_queues(&dev->ctrl);
2409 	if (pci_get_drvdata(pdev))
2410 		device_release_driver(&pdev->dev);
2411 	nvme_put_ctrl(&dev->ctrl);
2412 }
2413 
2414 static int nvme_pci_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val)
2415 {
2416 	*val = readl(to_nvme_dev(ctrl)->bar + off);
2417 	return 0;
2418 }
2419 
2420 static int nvme_pci_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val)
2421 {
2422 	writel(val, to_nvme_dev(ctrl)->bar + off);
2423 	return 0;
2424 }
2425 
2426 static int nvme_pci_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val)
2427 {
2428 	*val = readq(to_nvme_dev(ctrl)->bar + off);
2429 	return 0;
2430 }
2431 
2432 static int nvme_pci_get_address(struct nvme_ctrl *ctrl, char *buf, int size)
2433 {
2434 	struct pci_dev *pdev = to_pci_dev(to_nvme_dev(ctrl)->dev);
2435 
2436 	return snprintf(buf, size, "%s", dev_name(&pdev->dev));
2437 }
2438 
2439 static const struct nvme_ctrl_ops nvme_pci_ctrl_ops = {
2440 	.name			= "pcie",
2441 	.module			= THIS_MODULE,
2442 	.flags			= NVME_F_METADATA_SUPPORTED,
2443 	.reg_read32		= nvme_pci_reg_read32,
2444 	.reg_write32		= nvme_pci_reg_write32,
2445 	.reg_read64		= nvme_pci_reg_read64,
2446 	.free_ctrl		= nvme_pci_free_ctrl,
2447 	.submit_async_event	= nvme_pci_submit_async_event,
2448 	.get_address		= nvme_pci_get_address,
2449 };
2450 
2451 static int nvme_dev_map(struct nvme_dev *dev)
2452 {
2453 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2454 
2455 	if (pci_request_mem_regions(pdev, "nvme"))
2456 		return -ENODEV;
2457 
2458 	if (nvme_remap_bar(dev, NVME_REG_DBS + 4096))
2459 		goto release;
2460 
2461 	return 0;
2462   release:
2463 	pci_release_mem_regions(pdev);
2464 	return -ENODEV;
2465 }
2466 
2467 static unsigned long check_vendor_combination_bug(struct pci_dev *pdev)
2468 {
2469 	if (pdev->vendor == 0x144d && pdev->device == 0xa802) {
2470 		/*
2471 		 * Several Samsung devices seem to drop off the PCIe bus
2472 		 * randomly when APST is on and uses the deepest sleep state.
2473 		 * This has been observed on a Samsung "SM951 NVMe SAMSUNG
2474 		 * 256GB", a "PM951 NVMe SAMSUNG 512GB", and a "Samsung SSD
2475 		 * 950 PRO 256GB", but it seems to be restricted to two Dell
2476 		 * laptops.
2477 		 */
2478 		if (dmi_match(DMI_SYS_VENDOR, "Dell Inc.") &&
2479 		    (dmi_match(DMI_PRODUCT_NAME, "XPS 15 9550") ||
2480 		     dmi_match(DMI_PRODUCT_NAME, "Precision 5510")))
2481 			return NVME_QUIRK_NO_DEEPEST_PS;
2482 	} else if (pdev->vendor == 0x144d && pdev->device == 0xa804) {
2483 		/*
2484 		 * Samsung SSD 960 EVO drops off the PCIe bus after system
2485 		 * suspend on a Ryzen board, ASUS PRIME B350M-A, as well as
2486 		 * within few minutes after bootup on a Coffee Lake board -
2487 		 * ASUS PRIME Z370-A
2488 		 */
2489 		if (dmi_match(DMI_BOARD_VENDOR, "ASUSTeK COMPUTER INC.") &&
2490 		    (dmi_match(DMI_BOARD_NAME, "PRIME B350M-A") ||
2491 		     dmi_match(DMI_BOARD_NAME, "PRIME Z370-A")))
2492 			return NVME_QUIRK_NO_APST;
2493 	}
2494 
2495 	return 0;
2496 }
2497 
2498 static void nvme_async_probe(void *data, async_cookie_t cookie)
2499 {
2500 	struct nvme_dev *dev = data;
2501 
2502 	nvme_reset_ctrl_sync(&dev->ctrl);
2503 	flush_work(&dev->ctrl.scan_work);
2504 	nvme_put_ctrl(&dev->ctrl);
2505 }
2506 
2507 static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
2508 {
2509 	int node, result = -ENOMEM;
2510 	struct nvme_dev *dev;
2511 	unsigned long quirks = id->driver_data;
2512 
2513 	node = dev_to_node(&pdev->dev);
2514 	if (node == NUMA_NO_NODE)
2515 		set_dev_node(&pdev->dev, first_memory_node);
2516 
2517 	dev = kzalloc_node(sizeof(*dev), GFP_KERNEL, node);
2518 	if (!dev)
2519 		return -ENOMEM;
2520 
2521 	dev->queues = kcalloc_node(num_possible_cpus() + 1,
2522 			sizeof(struct nvme_queue), GFP_KERNEL, node);
2523 	if (!dev->queues)
2524 		goto free;
2525 
2526 	dev->dev = get_device(&pdev->dev);
2527 	pci_set_drvdata(pdev, dev);
2528 
2529 	result = nvme_dev_map(dev);
2530 	if (result)
2531 		goto put_pci;
2532 
2533 	INIT_WORK(&dev->ctrl.reset_work, nvme_reset_work);
2534 	INIT_WORK(&dev->remove_work, nvme_remove_dead_ctrl_work);
2535 	mutex_init(&dev->shutdown_lock);
2536 	init_completion(&dev->ioq_wait);
2537 
2538 	result = nvme_setup_prp_pools(dev);
2539 	if (result)
2540 		goto unmap;
2541 
2542 	quirks |= check_vendor_combination_bug(pdev);
2543 
2544 	result = nvme_init_ctrl(&dev->ctrl, &pdev->dev, &nvme_pci_ctrl_ops,
2545 			quirks);
2546 	if (result)
2547 		goto release_pools;
2548 
2549 	dev_info(dev->ctrl.device, "pci function %s\n", dev_name(&pdev->dev));
2550 
2551 	nvme_get_ctrl(&dev->ctrl);
2552 	async_schedule(nvme_async_probe, dev);
2553 
2554 	return 0;
2555 
2556  release_pools:
2557 	nvme_release_prp_pools(dev);
2558  unmap:
2559 	nvme_dev_unmap(dev);
2560  put_pci:
2561 	put_device(dev->dev);
2562  free:
2563 	kfree(dev->queues);
2564 	kfree(dev);
2565 	return result;
2566 }
2567 
2568 static void nvme_reset_prepare(struct pci_dev *pdev)
2569 {
2570 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2571 	nvme_dev_disable(dev, false);
2572 }
2573 
2574 static void nvme_reset_done(struct pci_dev *pdev)
2575 {
2576 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2577 	nvme_reset_ctrl_sync(&dev->ctrl);
2578 }
2579 
2580 static void nvme_shutdown(struct pci_dev *pdev)
2581 {
2582 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2583 	nvme_dev_disable(dev, true);
2584 }
2585 
2586 /*
2587  * The driver's remove may be called on a device in a partially initialized
2588  * state. This function must not have any dependencies on the device state in
2589  * order to proceed.
2590  */
2591 static void nvme_remove(struct pci_dev *pdev)
2592 {
2593 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2594 
2595 	nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DELETING);
2596 
2597 	cancel_work_sync(&dev->ctrl.reset_work);
2598 	pci_set_drvdata(pdev, NULL);
2599 
2600 	if (!pci_device_is_present(pdev)) {
2601 		nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DEAD);
2602 		nvme_dev_disable(dev, true);
2603 	}
2604 
2605 	flush_work(&dev->ctrl.reset_work);
2606 	nvme_stop_ctrl(&dev->ctrl);
2607 	nvme_remove_namespaces(&dev->ctrl);
2608 	nvme_dev_disable(dev, true);
2609 	nvme_free_host_mem(dev);
2610 	nvme_dev_remove_admin(dev);
2611 	nvme_free_queues(dev, 0);
2612 	nvme_uninit_ctrl(&dev->ctrl);
2613 	nvme_release_prp_pools(dev);
2614 	nvme_dev_unmap(dev);
2615 	nvme_put_ctrl(&dev->ctrl);
2616 }
2617 
2618 #ifdef CONFIG_PM_SLEEP
2619 static int nvme_suspend(struct device *dev)
2620 {
2621 	struct pci_dev *pdev = to_pci_dev(dev);
2622 	struct nvme_dev *ndev = pci_get_drvdata(pdev);
2623 
2624 	nvme_dev_disable(ndev, true);
2625 	return 0;
2626 }
2627 
2628 static int nvme_resume(struct device *dev)
2629 {
2630 	struct pci_dev *pdev = to_pci_dev(dev);
2631 	struct nvme_dev *ndev = pci_get_drvdata(pdev);
2632 
2633 	nvme_reset_ctrl(&ndev->ctrl);
2634 	return 0;
2635 }
2636 #endif
2637 
2638 static SIMPLE_DEV_PM_OPS(nvme_dev_pm_ops, nvme_suspend, nvme_resume);
2639 
2640 static pci_ers_result_t nvme_error_detected(struct pci_dev *pdev,
2641 						pci_channel_state_t state)
2642 {
2643 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2644 
2645 	/*
2646 	 * A frozen channel requires a reset. When detected, this method will
2647 	 * shutdown the controller to quiesce. The controller will be restarted
2648 	 * after the slot reset through driver's slot_reset callback.
2649 	 */
2650 	switch (state) {
2651 	case pci_channel_io_normal:
2652 		return PCI_ERS_RESULT_CAN_RECOVER;
2653 	case pci_channel_io_frozen:
2654 		dev_warn(dev->ctrl.device,
2655 			"frozen state error detected, reset controller\n");
2656 		nvme_dev_disable(dev, false);
2657 		return PCI_ERS_RESULT_NEED_RESET;
2658 	case pci_channel_io_perm_failure:
2659 		dev_warn(dev->ctrl.device,
2660 			"failure state error detected, request disconnect\n");
2661 		return PCI_ERS_RESULT_DISCONNECT;
2662 	}
2663 	return PCI_ERS_RESULT_NEED_RESET;
2664 }
2665 
2666 static pci_ers_result_t nvme_slot_reset(struct pci_dev *pdev)
2667 {
2668 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2669 
2670 	dev_info(dev->ctrl.device, "restart after slot reset\n");
2671 	pci_restore_state(pdev);
2672 	nvme_reset_ctrl(&dev->ctrl);
2673 	return PCI_ERS_RESULT_RECOVERED;
2674 }
2675 
2676 static void nvme_error_resume(struct pci_dev *pdev)
2677 {
2678 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2679 
2680 	flush_work(&dev->ctrl.reset_work);
2681 	pci_cleanup_aer_uncorrect_error_status(pdev);
2682 }
2683 
2684 static const struct pci_error_handlers nvme_err_handler = {
2685 	.error_detected	= nvme_error_detected,
2686 	.slot_reset	= nvme_slot_reset,
2687 	.resume		= nvme_error_resume,
2688 	.reset_prepare	= nvme_reset_prepare,
2689 	.reset_done	= nvme_reset_done,
2690 };
2691 
2692 static const struct pci_device_id nvme_id_table[] = {
2693 	{ PCI_VDEVICE(INTEL, 0x0953),
2694 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
2695 				NVME_QUIRK_DEALLOCATE_ZEROES, },
2696 	{ PCI_VDEVICE(INTEL, 0x0a53),
2697 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
2698 				NVME_QUIRK_DEALLOCATE_ZEROES, },
2699 	{ PCI_VDEVICE(INTEL, 0x0a54),
2700 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
2701 				NVME_QUIRK_DEALLOCATE_ZEROES, },
2702 	{ PCI_VDEVICE(INTEL, 0x0a55),
2703 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
2704 				NVME_QUIRK_DEALLOCATE_ZEROES, },
2705 	{ PCI_VDEVICE(INTEL, 0xf1a5),	/* Intel 600P/P3100 */
2706 		.driver_data = NVME_QUIRK_NO_DEEPEST_PS |
2707 				NVME_QUIRK_MEDIUM_PRIO_SQ },
2708 	{ PCI_VDEVICE(INTEL, 0x5845),	/* Qemu emulated controller */
2709 		.driver_data = NVME_QUIRK_IDENTIFY_CNS, },
2710 	{ PCI_DEVICE(0x1bb1, 0x0100),   /* Seagate Nytro Flash Storage */
2711 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2712 	{ PCI_DEVICE(0x1c58, 0x0003),	/* HGST adapter */
2713 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2714 	{ PCI_DEVICE(0x1c58, 0x0023),	/* WDC SN200 adapter */
2715 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2716 	{ PCI_DEVICE(0x1c5f, 0x0540),	/* Memblaze Pblaze4 adapter */
2717 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2718 	{ PCI_DEVICE(0x144d, 0xa821),   /* Samsung PM1725 */
2719 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2720 	{ PCI_DEVICE(0x144d, 0xa822),   /* Samsung PM1725a */
2721 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2722 	{ PCI_DEVICE(0x1d1d, 0x1f1f),	/* LighNVM qemu device */
2723 		.driver_data = NVME_QUIRK_LIGHTNVM, },
2724 	{ PCI_DEVICE(0x1d1d, 0x2807),	/* CNEX WL */
2725 		.driver_data = NVME_QUIRK_LIGHTNVM, },
2726 	{ PCI_DEVICE(0x1d1d, 0x2601),	/* CNEX Granby */
2727 		.driver_data = NVME_QUIRK_LIGHTNVM, },
2728 	{ PCI_DEVICE_CLASS(PCI_CLASS_STORAGE_EXPRESS, 0xffffff) },
2729 	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2001) },
2730 	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2003) },
2731 	{ 0, }
2732 };
2733 MODULE_DEVICE_TABLE(pci, nvme_id_table);
2734 
2735 static struct pci_driver nvme_driver = {
2736 	.name		= "nvme",
2737 	.id_table	= nvme_id_table,
2738 	.probe		= nvme_probe,
2739 	.remove		= nvme_remove,
2740 	.shutdown	= nvme_shutdown,
2741 	.driver		= {
2742 		.pm	= &nvme_dev_pm_ops,
2743 	},
2744 	.sriov_configure = pci_sriov_configure_simple,
2745 	.err_handler	= &nvme_err_handler,
2746 };
2747 
2748 static int __init nvme_init(void)
2749 {
2750 	return pci_register_driver(&nvme_driver);
2751 }
2752 
2753 static void __exit nvme_exit(void)
2754 {
2755 	pci_unregister_driver(&nvme_driver);
2756 	flush_workqueue(nvme_wq);
2757 	_nvme_check_size();
2758 }
2759 
2760 MODULE_AUTHOR("Matthew Wilcox <willy@linux.intel.com>");
2761 MODULE_LICENSE("GPL");
2762 MODULE_VERSION("1.0");
2763 module_init(nvme_init);
2764 module_exit(nvme_exit);
2765