xref: /openbmc/linux/drivers/nvme/host/pci.c (revision b9b77222)
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 /*
42  * These can be higher, but we need to ensure that any command doesn't
43  * require an sg allocation that needs more than a page of data.
44  */
45 #define NVME_MAX_KB_SZ	4096
46 #define NVME_MAX_SEGS	127
47 
48 static int use_threaded_interrupts;
49 module_param(use_threaded_interrupts, int, 0);
50 
51 static bool use_cmb_sqes = true;
52 module_param(use_cmb_sqes, bool, 0444);
53 MODULE_PARM_DESC(use_cmb_sqes, "use controller's memory buffer for I/O SQes");
54 
55 static unsigned int max_host_mem_size_mb = 128;
56 module_param(max_host_mem_size_mb, uint, 0444);
57 MODULE_PARM_DESC(max_host_mem_size_mb,
58 	"Maximum Host Memory Buffer (HMB) size per controller (in MiB)");
59 
60 static unsigned int sgl_threshold = SZ_32K;
61 module_param(sgl_threshold, uint, 0644);
62 MODULE_PARM_DESC(sgl_threshold,
63 		"Use SGLs when average request segment size is larger or equal to "
64 		"this size. Use 0 to disable SGLs.");
65 
66 static int io_queue_depth_set(const char *val, const struct kernel_param *kp);
67 static const struct kernel_param_ops io_queue_depth_ops = {
68 	.set = io_queue_depth_set,
69 	.get = param_get_int,
70 };
71 
72 static int io_queue_depth = 1024;
73 module_param_cb(io_queue_depth, &io_queue_depth_ops, &io_queue_depth, 0644);
74 MODULE_PARM_DESC(io_queue_depth, "set io queue depth, should >= 2");
75 
76 struct nvme_dev;
77 struct nvme_queue;
78 
79 static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown);
80 
81 /*
82  * Represents an NVM Express device.  Each nvme_dev is a PCI function.
83  */
84 struct nvme_dev {
85 	struct nvme_queue *queues;
86 	struct blk_mq_tag_set tagset;
87 	struct blk_mq_tag_set admin_tagset;
88 	u32 __iomem *dbs;
89 	struct device *dev;
90 	struct dma_pool *prp_page_pool;
91 	struct dma_pool *prp_small_pool;
92 	unsigned online_queues;
93 	unsigned max_qid;
94 	unsigned int num_vecs;
95 	int q_depth;
96 	u32 db_stride;
97 	void __iomem *bar;
98 	unsigned long bar_mapped_size;
99 	struct work_struct remove_work;
100 	struct mutex shutdown_lock;
101 	bool subsystem;
102 	void __iomem *cmb;
103 	pci_bus_addr_t cmb_bus_addr;
104 	u64 cmb_size;
105 	u32 cmbsz;
106 	u32 cmbloc;
107 	struct nvme_ctrl ctrl;
108 	struct completion ioq_wait;
109 
110 	mempool_t *iod_mempool;
111 
112 	/* shadow doorbell buffer support: */
113 	u32 *dbbuf_dbs;
114 	dma_addr_t dbbuf_dbs_dma_addr;
115 	u32 *dbbuf_eis;
116 	dma_addr_t dbbuf_eis_dma_addr;
117 
118 	/* host memory buffer support: */
119 	u64 host_mem_size;
120 	u32 nr_host_mem_descs;
121 	dma_addr_t host_mem_descs_dma;
122 	struct nvme_host_mem_buf_desc *host_mem_descs;
123 	void **host_mem_desc_bufs;
124 };
125 
126 static int io_queue_depth_set(const char *val, const struct kernel_param *kp)
127 {
128 	int n = 0, ret;
129 
130 	ret = kstrtoint(val, 10, &n);
131 	if (ret != 0 || n < 2)
132 		return -EINVAL;
133 
134 	return param_set_int(val, kp);
135 }
136 
137 static inline unsigned int sq_idx(unsigned int qid, u32 stride)
138 {
139 	return qid * 2 * stride;
140 }
141 
142 static inline unsigned int cq_idx(unsigned int qid, u32 stride)
143 {
144 	return (qid * 2 + 1) * stride;
145 }
146 
147 static inline struct nvme_dev *to_nvme_dev(struct nvme_ctrl *ctrl)
148 {
149 	return container_of(ctrl, struct nvme_dev, ctrl);
150 }
151 
152 /*
153  * An NVM Express queue.  Each device has at least two (one for admin
154  * commands and one for I/O commands).
155  */
156 struct nvme_queue {
157 	struct device *q_dmadev;
158 	struct nvme_dev *dev;
159 	spinlock_t sq_lock;
160 	struct nvme_command *sq_cmds;
161 	struct nvme_command __iomem *sq_cmds_io;
162 	spinlock_t cq_lock ____cacheline_aligned_in_smp;
163 	volatile struct nvme_completion *cqes;
164 	struct blk_mq_tags **tags;
165 	dma_addr_t sq_dma_addr;
166 	dma_addr_t cq_dma_addr;
167 	u32 __iomem *q_db;
168 	u16 q_depth;
169 	s16 cq_vector;
170 	u16 sq_tail;
171 	u16 cq_head;
172 	u16 last_cq_head;
173 	u16 qid;
174 	u8 cq_phase;
175 	u32 *dbbuf_sq_db;
176 	u32 *dbbuf_cq_db;
177 	u32 *dbbuf_sq_ei;
178 	u32 *dbbuf_cq_ei;
179 };
180 
181 /*
182  * The nvme_iod describes the data in an I/O, including the list of PRP
183  * entries.  You can't see it in this data structure because C doesn't let
184  * me express that.  Use nvme_init_iod to ensure there's enough space
185  * allocated to store the PRP list.
186  */
187 struct nvme_iod {
188 	struct nvme_request req;
189 	struct nvme_queue *nvmeq;
190 	bool use_sgl;
191 	int aborted;
192 	int npages;		/* In the PRP list. 0 means small pool in use */
193 	int nents;		/* Used in scatterlist */
194 	int length;		/* Of data, in bytes */
195 	dma_addr_t first_dma;
196 	struct scatterlist meta_sg; /* metadata requires single contiguous buffer */
197 	struct scatterlist *sg;
198 	struct scatterlist inline_sg[0];
199 };
200 
201 /*
202  * Check we didin't inadvertently grow the command struct
203  */
204 static inline void _nvme_check_size(void)
205 {
206 	BUILD_BUG_ON(sizeof(struct nvme_rw_command) != 64);
207 	BUILD_BUG_ON(sizeof(struct nvme_create_cq) != 64);
208 	BUILD_BUG_ON(sizeof(struct nvme_create_sq) != 64);
209 	BUILD_BUG_ON(sizeof(struct nvme_delete_queue) != 64);
210 	BUILD_BUG_ON(sizeof(struct nvme_features) != 64);
211 	BUILD_BUG_ON(sizeof(struct nvme_format_cmd) != 64);
212 	BUILD_BUG_ON(sizeof(struct nvme_abort_cmd) != 64);
213 	BUILD_BUG_ON(sizeof(struct nvme_command) != 64);
214 	BUILD_BUG_ON(sizeof(struct nvme_id_ctrl) != NVME_IDENTIFY_DATA_SIZE);
215 	BUILD_BUG_ON(sizeof(struct nvme_id_ns) != NVME_IDENTIFY_DATA_SIZE);
216 	BUILD_BUG_ON(sizeof(struct nvme_lba_range_type) != 64);
217 	BUILD_BUG_ON(sizeof(struct nvme_smart_log) != 512);
218 	BUILD_BUG_ON(sizeof(struct nvme_dbbuf) != 64);
219 }
220 
221 static inline unsigned int nvme_dbbuf_size(u32 stride)
222 {
223 	return ((num_possible_cpus() + 1) * 8 * stride);
224 }
225 
226 static int nvme_dbbuf_dma_alloc(struct nvme_dev *dev)
227 {
228 	unsigned int mem_size = nvme_dbbuf_size(dev->db_stride);
229 
230 	if (dev->dbbuf_dbs)
231 		return 0;
232 
233 	dev->dbbuf_dbs = dma_alloc_coherent(dev->dev, mem_size,
234 					    &dev->dbbuf_dbs_dma_addr,
235 					    GFP_KERNEL);
236 	if (!dev->dbbuf_dbs)
237 		return -ENOMEM;
238 	dev->dbbuf_eis = dma_alloc_coherent(dev->dev, mem_size,
239 					    &dev->dbbuf_eis_dma_addr,
240 					    GFP_KERNEL);
241 	if (!dev->dbbuf_eis) {
242 		dma_free_coherent(dev->dev, mem_size,
243 				  dev->dbbuf_dbs, dev->dbbuf_dbs_dma_addr);
244 		dev->dbbuf_dbs = NULL;
245 		return -ENOMEM;
246 	}
247 
248 	return 0;
249 }
250 
251 static void nvme_dbbuf_dma_free(struct nvme_dev *dev)
252 {
253 	unsigned int mem_size = nvme_dbbuf_size(dev->db_stride);
254 
255 	if (dev->dbbuf_dbs) {
256 		dma_free_coherent(dev->dev, mem_size,
257 				  dev->dbbuf_dbs, dev->dbbuf_dbs_dma_addr);
258 		dev->dbbuf_dbs = NULL;
259 	}
260 	if (dev->dbbuf_eis) {
261 		dma_free_coherent(dev->dev, mem_size,
262 				  dev->dbbuf_eis, dev->dbbuf_eis_dma_addr);
263 		dev->dbbuf_eis = NULL;
264 	}
265 }
266 
267 static void nvme_dbbuf_init(struct nvme_dev *dev,
268 			    struct nvme_queue *nvmeq, int qid)
269 {
270 	if (!dev->dbbuf_dbs || !qid)
271 		return;
272 
273 	nvmeq->dbbuf_sq_db = &dev->dbbuf_dbs[sq_idx(qid, dev->db_stride)];
274 	nvmeq->dbbuf_cq_db = &dev->dbbuf_dbs[cq_idx(qid, dev->db_stride)];
275 	nvmeq->dbbuf_sq_ei = &dev->dbbuf_eis[sq_idx(qid, dev->db_stride)];
276 	nvmeq->dbbuf_cq_ei = &dev->dbbuf_eis[cq_idx(qid, dev->db_stride)];
277 }
278 
279 static void nvme_dbbuf_set(struct nvme_dev *dev)
280 {
281 	struct nvme_command c;
282 
283 	if (!dev->dbbuf_dbs)
284 		return;
285 
286 	memset(&c, 0, sizeof(c));
287 	c.dbbuf.opcode = nvme_admin_dbbuf;
288 	c.dbbuf.prp1 = cpu_to_le64(dev->dbbuf_dbs_dma_addr);
289 	c.dbbuf.prp2 = cpu_to_le64(dev->dbbuf_eis_dma_addr);
290 
291 	if (nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0)) {
292 		dev_warn(dev->ctrl.device, "unable to set dbbuf\n");
293 		/* Free memory and continue on */
294 		nvme_dbbuf_dma_free(dev);
295 	}
296 }
297 
298 static inline int nvme_dbbuf_need_event(u16 event_idx, u16 new_idx, u16 old)
299 {
300 	return (u16)(new_idx - event_idx - 1) < (u16)(new_idx - old);
301 }
302 
303 /* Update dbbuf and return true if an MMIO is required */
304 static bool nvme_dbbuf_update_and_check_event(u16 value, u32 *dbbuf_db,
305 					      volatile u32 *dbbuf_ei)
306 {
307 	if (dbbuf_db) {
308 		u16 old_value;
309 
310 		/*
311 		 * Ensure that the queue is written before updating
312 		 * the doorbell in memory
313 		 */
314 		wmb();
315 
316 		old_value = *dbbuf_db;
317 		*dbbuf_db = value;
318 
319 		if (!nvme_dbbuf_need_event(*dbbuf_ei, value, old_value))
320 			return false;
321 	}
322 
323 	return true;
324 }
325 
326 /*
327  * Max size of iod being embedded in the request payload
328  */
329 #define NVME_INT_PAGES		2
330 #define NVME_INT_BYTES(dev)	(NVME_INT_PAGES * (dev)->ctrl.page_size)
331 
332 /*
333  * Will slightly overestimate the number of pages needed.  This is OK
334  * as it only leads to a small amount of wasted memory for the lifetime of
335  * the I/O.
336  */
337 static int nvme_npages(unsigned size, struct nvme_dev *dev)
338 {
339 	unsigned nprps = DIV_ROUND_UP(size + dev->ctrl.page_size,
340 				      dev->ctrl.page_size);
341 	return DIV_ROUND_UP(8 * nprps, PAGE_SIZE - 8);
342 }
343 
344 /*
345  * Calculates the number of pages needed for the SGL segments. For example a 4k
346  * page can accommodate 256 SGL descriptors.
347  */
348 static int nvme_pci_npages_sgl(unsigned int num_seg)
349 {
350 	return DIV_ROUND_UP(num_seg * sizeof(struct nvme_sgl_desc), PAGE_SIZE);
351 }
352 
353 static unsigned int nvme_pci_iod_alloc_size(struct nvme_dev *dev,
354 		unsigned int size, unsigned int nseg, bool use_sgl)
355 {
356 	size_t alloc_size;
357 
358 	if (use_sgl)
359 		alloc_size = sizeof(__le64 *) * nvme_pci_npages_sgl(nseg);
360 	else
361 		alloc_size = sizeof(__le64 *) * nvme_npages(size, dev);
362 
363 	return alloc_size + sizeof(struct scatterlist) * nseg;
364 }
365 
366 static unsigned int nvme_pci_cmd_size(struct nvme_dev *dev, bool use_sgl)
367 {
368 	unsigned int alloc_size = nvme_pci_iod_alloc_size(dev,
369 				    NVME_INT_BYTES(dev), NVME_INT_PAGES,
370 				    use_sgl);
371 
372 	return sizeof(struct nvme_iod) + alloc_size;
373 }
374 
375 static int nvme_admin_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
376 				unsigned int hctx_idx)
377 {
378 	struct nvme_dev *dev = data;
379 	struct nvme_queue *nvmeq = &dev->queues[0];
380 
381 	WARN_ON(hctx_idx != 0);
382 	WARN_ON(dev->admin_tagset.tags[0] != hctx->tags);
383 	WARN_ON(nvmeq->tags);
384 
385 	hctx->driver_data = nvmeq;
386 	nvmeq->tags = &dev->admin_tagset.tags[0];
387 	return 0;
388 }
389 
390 static void nvme_admin_exit_hctx(struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx)
391 {
392 	struct nvme_queue *nvmeq = hctx->driver_data;
393 
394 	nvmeq->tags = NULL;
395 }
396 
397 static int nvme_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
398 			  unsigned int hctx_idx)
399 {
400 	struct nvme_dev *dev = data;
401 	struct nvme_queue *nvmeq = &dev->queues[hctx_idx + 1];
402 
403 	if (!nvmeq->tags)
404 		nvmeq->tags = &dev->tagset.tags[hctx_idx];
405 
406 	WARN_ON(dev->tagset.tags[hctx_idx] != hctx->tags);
407 	hctx->driver_data = nvmeq;
408 	return 0;
409 }
410 
411 static int nvme_init_request(struct blk_mq_tag_set *set, struct request *req,
412 		unsigned int hctx_idx, unsigned int numa_node)
413 {
414 	struct nvme_dev *dev = set->driver_data;
415 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
416 	int queue_idx = (set == &dev->tagset) ? hctx_idx + 1 : 0;
417 	struct nvme_queue *nvmeq = &dev->queues[queue_idx];
418 
419 	BUG_ON(!nvmeq);
420 	iod->nvmeq = nvmeq;
421 	return 0;
422 }
423 
424 static int nvme_pci_map_queues(struct blk_mq_tag_set *set)
425 {
426 	struct nvme_dev *dev = set->driver_data;
427 
428 	return blk_mq_pci_map_queues(set, to_pci_dev(dev->dev),
429 			dev->num_vecs > 1 ? 1 /* admin queue */ : 0);
430 }
431 
432 /**
433  * nvme_submit_cmd() - Copy a command into a queue and ring the doorbell
434  * @nvmeq: The queue to use
435  * @cmd: The command to send
436  */
437 static void nvme_submit_cmd(struct nvme_queue *nvmeq, struct nvme_command *cmd)
438 {
439 	spin_lock(&nvmeq->sq_lock);
440 	if (nvmeq->sq_cmds_io)
441 		memcpy_toio(&nvmeq->sq_cmds_io[nvmeq->sq_tail], cmd,
442 				sizeof(*cmd));
443 	else
444 		memcpy(&nvmeq->sq_cmds[nvmeq->sq_tail], cmd, sizeof(*cmd));
445 
446 	if (++nvmeq->sq_tail == nvmeq->q_depth)
447 		nvmeq->sq_tail = 0;
448 	if (nvme_dbbuf_update_and_check_event(nvmeq->sq_tail,
449 			nvmeq->dbbuf_sq_db, nvmeq->dbbuf_sq_ei))
450 		writel(nvmeq->sq_tail, nvmeq->q_db);
451 	spin_unlock(&nvmeq->sq_lock);
452 }
453 
454 static void **nvme_pci_iod_list(struct request *req)
455 {
456 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
457 	return (void **)(iod->sg + blk_rq_nr_phys_segments(req));
458 }
459 
460 static inline bool nvme_pci_use_sgls(struct nvme_dev *dev, struct request *req)
461 {
462 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
463 	int nseg = blk_rq_nr_phys_segments(req);
464 	unsigned int avg_seg_size;
465 
466 	if (nseg == 0)
467 		return false;
468 
469 	avg_seg_size = DIV_ROUND_UP(blk_rq_payload_bytes(req), nseg);
470 
471 	if (!(dev->ctrl.sgls & ((1 << 0) | (1 << 1))))
472 		return false;
473 	if (!iod->nvmeq->qid)
474 		return false;
475 	if (!sgl_threshold || avg_seg_size < sgl_threshold)
476 		return false;
477 	return true;
478 }
479 
480 static blk_status_t nvme_init_iod(struct request *rq, struct nvme_dev *dev)
481 {
482 	struct nvme_iod *iod = blk_mq_rq_to_pdu(rq);
483 	int nseg = blk_rq_nr_phys_segments(rq);
484 	unsigned int size = blk_rq_payload_bytes(rq);
485 
486 	iod->use_sgl = nvme_pci_use_sgls(dev, rq);
487 
488 	if (nseg > NVME_INT_PAGES || size > NVME_INT_BYTES(dev)) {
489 		iod->sg = mempool_alloc(dev->iod_mempool, GFP_ATOMIC);
490 		if (!iod->sg)
491 			return BLK_STS_RESOURCE;
492 	} else {
493 		iod->sg = iod->inline_sg;
494 	}
495 
496 	iod->aborted = 0;
497 	iod->npages = -1;
498 	iod->nents = 0;
499 	iod->length = size;
500 
501 	return BLK_STS_OK;
502 }
503 
504 static void nvme_free_iod(struct nvme_dev *dev, struct request *req)
505 {
506 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
507 	const int last_prp = dev->ctrl.page_size / sizeof(__le64) - 1;
508 	dma_addr_t dma_addr = iod->first_dma, next_dma_addr;
509 
510 	int i;
511 
512 	if (iod->npages == 0)
513 		dma_pool_free(dev->prp_small_pool, nvme_pci_iod_list(req)[0],
514 			dma_addr);
515 
516 	for (i = 0; i < iod->npages; i++) {
517 		void *addr = nvme_pci_iod_list(req)[i];
518 
519 		if (iod->use_sgl) {
520 			struct nvme_sgl_desc *sg_list = addr;
521 
522 			next_dma_addr =
523 			    le64_to_cpu((sg_list[SGES_PER_PAGE - 1]).addr);
524 		} else {
525 			__le64 *prp_list = addr;
526 
527 			next_dma_addr = le64_to_cpu(prp_list[last_prp]);
528 		}
529 
530 		dma_pool_free(dev->prp_page_pool, addr, dma_addr);
531 		dma_addr = next_dma_addr;
532 	}
533 
534 	if (iod->sg != iod->inline_sg)
535 		mempool_free(iod->sg, dev->iod_mempool);
536 }
537 
538 #ifdef CONFIG_BLK_DEV_INTEGRITY
539 static void nvme_dif_prep(u32 p, u32 v, struct t10_pi_tuple *pi)
540 {
541 	if (be32_to_cpu(pi->ref_tag) == v)
542 		pi->ref_tag = cpu_to_be32(p);
543 }
544 
545 static void nvme_dif_complete(u32 p, u32 v, struct t10_pi_tuple *pi)
546 {
547 	if (be32_to_cpu(pi->ref_tag) == p)
548 		pi->ref_tag = cpu_to_be32(v);
549 }
550 
551 /**
552  * nvme_dif_remap - remaps ref tags to bip seed and physical lba
553  *
554  * The virtual start sector is the one that was originally submitted by the
555  * block layer.	Due to partitioning, MD/DM cloning, etc. the actual physical
556  * start sector may be different. Remap protection information to match the
557  * physical LBA on writes, and back to the original seed on reads.
558  *
559  * Type 0 and 3 do not have a ref tag, so no remapping required.
560  */
561 static void nvme_dif_remap(struct request *req,
562 			void (*dif_swap)(u32 p, u32 v, struct t10_pi_tuple *pi))
563 {
564 	struct nvme_ns *ns = req->rq_disk->private_data;
565 	struct bio_integrity_payload *bip;
566 	struct t10_pi_tuple *pi;
567 	void *p, *pmap;
568 	u32 i, nlb, ts, phys, virt;
569 
570 	if (!ns->pi_type || ns->pi_type == NVME_NS_DPS_PI_TYPE3)
571 		return;
572 
573 	bip = bio_integrity(req->bio);
574 	if (!bip)
575 		return;
576 
577 	pmap = kmap_atomic(bip->bip_vec->bv_page) + bip->bip_vec->bv_offset;
578 
579 	p = pmap;
580 	virt = bip_get_seed(bip);
581 	phys = nvme_block_nr(ns, blk_rq_pos(req));
582 	nlb = (blk_rq_bytes(req) >> ns->lba_shift);
583 	ts = ns->disk->queue->integrity.tuple_size;
584 
585 	for (i = 0; i < nlb; i++, virt++, phys++) {
586 		pi = (struct t10_pi_tuple *)p;
587 		dif_swap(phys, virt, pi);
588 		p += ts;
589 	}
590 	kunmap_atomic(pmap);
591 }
592 #else /* CONFIG_BLK_DEV_INTEGRITY */
593 static void nvme_dif_remap(struct request *req,
594 			void (*dif_swap)(u32 p, u32 v, struct t10_pi_tuple *pi))
595 {
596 }
597 static void nvme_dif_prep(u32 p, u32 v, struct t10_pi_tuple *pi)
598 {
599 }
600 static void nvme_dif_complete(u32 p, u32 v, struct t10_pi_tuple *pi)
601 {
602 }
603 #endif
604 
605 static void nvme_print_sgl(struct scatterlist *sgl, int nents)
606 {
607 	int i;
608 	struct scatterlist *sg;
609 
610 	for_each_sg(sgl, sg, nents, i) {
611 		dma_addr_t phys = sg_phys(sg);
612 		pr_warn("sg[%d] phys_addr:%pad offset:%d length:%d "
613 			"dma_address:%pad dma_length:%d\n",
614 			i, &phys, sg->offset, sg->length, &sg_dma_address(sg),
615 			sg_dma_len(sg));
616 	}
617 }
618 
619 static blk_status_t nvme_pci_setup_prps(struct nvme_dev *dev,
620 		struct request *req, struct nvme_rw_command *cmnd)
621 {
622 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
623 	struct dma_pool *pool;
624 	int length = blk_rq_payload_bytes(req);
625 	struct scatterlist *sg = iod->sg;
626 	int dma_len = sg_dma_len(sg);
627 	u64 dma_addr = sg_dma_address(sg);
628 	u32 page_size = dev->ctrl.page_size;
629 	int offset = dma_addr & (page_size - 1);
630 	__le64 *prp_list;
631 	void **list = nvme_pci_iod_list(req);
632 	dma_addr_t prp_dma;
633 	int nprps, i;
634 
635 	length -= (page_size - offset);
636 	if (length <= 0) {
637 		iod->first_dma = 0;
638 		goto done;
639 	}
640 
641 	dma_len -= (page_size - offset);
642 	if (dma_len) {
643 		dma_addr += (page_size - offset);
644 	} else {
645 		sg = sg_next(sg);
646 		dma_addr = sg_dma_address(sg);
647 		dma_len = sg_dma_len(sg);
648 	}
649 
650 	if (length <= page_size) {
651 		iod->first_dma = dma_addr;
652 		goto done;
653 	}
654 
655 	nprps = DIV_ROUND_UP(length, page_size);
656 	if (nprps <= (256 / 8)) {
657 		pool = dev->prp_small_pool;
658 		iod->npages = 0;
659 	} else {
660 		pool = dev->prp_page_pool;
661 		iod->npages = 1;
662 	}
663 
664 	prp_list = dma_pool_alloc(pool, GFP_ATOMIC, &prp_dma);
665 	if (!prp_list) {
666 		iod->first_dma = dma_addr;
667 		iod->npages = -1;
668 		return BLK_STS_RESOURCE;
669 	}
670 	list[0] = prp_list;
671 	iod->first_dma = prp_dma;
672 	i = 0;
673 	for (;;) {
674 		if (i == page_size >> 3) {
675 			__le64 *old_prp_list = prp_list;
676 			prp_list = dma_pool_alloc(pool, GFP_ATOMIC, &prp_dma);
677 			if (!prp_list)
678 				return BLK_STS_RESOURCE;
679 			list[iod->npages++] = prp_list;
680 			prp_list[0] = old_prp_list[i - 1];
681 			old_prp_list[i - 1] = cpu_to_le64(prp_dma);
682 			i = 1;
683 		}
684 		prp_list[i++] = cpu_to_le64(dma_addr);
685 		dma_len -= page_size;
686 		dma_addr += page_size;
687 		length -= page_size;
688 		if (length <= 0)
689 			break;
690 		if (dma_len > 0)
691 			continue;
692 		if (unlikely(dma_len < 0))
693 			goto bad_sgl;
694 		sg = sg_next(sg);
695 		dma_addr = sg_dma_address(sg);
696 		dma_len = sg_dma_len(sg);
697 	}
698 
699 done:
700 	cmnd->dptr.prp1 = cpu_to_le64(sg_dma_address(iod->sg));
701 	cmnd->dptr.prp2 = cpu_to_le64(iod->first_dma);
702 
703 	return BLK_STS_OK;
704 
705  bad_sgl:
706 	WARN(DO_ONCE(nvme_print_sgl, iod->sg, iod->nents),
707 			"Invalid SGL for payload:%d nents:%d\n",
708 			blk_rq_payload_bytes(req), iod->nents);
709 	return BLK_STS_IOERR;
710 }
711 
712 static void nvme_pci_sgl_set_data(struct nvme_sgl_desc *sge,
713 		struct scatterlist *sg)
714 {
715 	sge->addr = cpu_to_le64(sg_dma_address(sg));
716 	sge->length = cpu_to_le32(sg_dma_len(sg));
717 	sge->type = NVME_SGL_FMT_DATA_DESC << 4;
718 }
719 
720 static void nvme_pci_sgl_set_seg(struct nvme_sgl_desc *sge,
721 		dma_addr_t dma_addr, int entries)
722 {
723 	sge->addr = cpu_to_le64(dma_addr);
724 	if (entries < SGES_PER_PAGE) {
725 		sge->length = cpu_to_le32(entries * sizeof(*sge));
726 		sge->type = NVME_SGL_FMT_LAST_SEG_DESC << 4;
727 	} else {
728 		sge->length = cpu_to_le32(PAGE_SIZE);
729 		sge->type = NVME_SGL_FMT_SEG_DESC << 4;
730 	}
731 }
732 
733 static blk_status_t nvme_pci_setup_sgls(struct nvme_dev *dev,
734 		struct request *req, struct nvme_rw_command *cmd, int entries)
735 {
736 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
737 	struct dma_pool *pool;
738 	struct nvme_sgl_desc *sg_list;
739 	struct scatterlist *sg = iod->sg;
740 	dma_addr_t sgl_dma;
741 	int i = 0;
742 
743 	/* setting the transfer type as SGL */
744 	cmd->flags = NVME_CMD_SGL_METABUF;
745 
746 	if (entries == 1) {
747 		nvme_pci_sgl_set_data(&cmd->dptr.sgl, sg);
748 		return BLK_STS_OK;
749 	}
750 
751 	if (entries <= (256 / sizeof(struct nvme_sgl_desc))) {
752 		pool = dev->prp_small_pool;
753 		iod->npages = 0;
754 	} else {
755 		pool = dev->prp_page_pool;
756 		iod->npages = 1;
757 	}
758 
759 	sg_list = dma_pool_alloc(pool, GFP_ATOMIC, &sgl_dma);
760 	if (!sg_list) {
761 		iod->npages = -1;
762 		return BLK_STS_RESOURCE;
763 	}
764 
765 	nvme_pci_iod_list(req)[0] = sg_list;
766 	iod->first_dma = sgl_dma;
767 
768 	nvme_pci_sgl_set_seg(&cmd->dptr.sgl, sgl_dma, entries);
769 
770 	do {
771 		if (i == SGES_PER_PAGE) {
772 			struct nvme_sgl_desc *old_sg_desc = sg_list;
773 			struct nvme_sgl_desc *link = &old_sg_desc[i - 1];
774 
775 			sg_list = dma_pool_alloc(pool, GFP_ATOMIC, &sgl_dma);
776 			if (!sg_list)
777 				return BLK_STS_RESOURCE;
778 
779 			i = 0;
780 			nvme_pci_iod_list(req)[iod->npages++] = sg_list;
781 			sg_list[i++] = *link;
782 			nvme_pci_sgl_set_seg(link, sgl_dma, entries);
783 		}
784 
785 		nvme_pci_sgl_set_data(&sg_list[i++], sg);
786 		sg = sg_next(sg);
787 	} while (--entries > 0);
788 
789 	return BLK_STS_OK;
790 }
791 
792 static blk_status_t nvme_map_data(struct nvme_dev *dev, struct request *req,
793 		struct nvme_command *cmnd)
794 {
795 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
796 	struct request_queue *q = req->q;
797 	enum dma_data_direction dma_dir = rq_data_dir(req) ?
798 			DMA_TO_DEVICE : DMA_FROM_DEVICE;
799 	blk_status_t ret = BLK_STS_IOERR;
800 	int nr_mapped;
801 
802 	sg_init_table(iod->sg, blk_rq_nr_phys_segments(req));
803 	iod->nents = blk_rq_map_sg(q, req, iod->sg);
804 	if (!iod->nents)
805 		goto out;
806 
807 	ret = BLK_STS_RESOURCE;
808 	nr_mapped = dma_map_sg_attrs(dev->dev, iod->sg, iod->nents, dma_dir,
809 			DMA_ATTR_NO_WARN);
810 	if (!nr_mapped)
811 		goto out;
812 
813 	if (iod->use_sgl)
814 		ret = nvme_pci_setup_sgls(dev, req, &cmnd->rw, nr_mapped);
815 	else
816 		ret = nvme_pci_setup_prps(dev, req, &cmnd->rw);
817 
818 	if (ret != BLK_STS_OK)
819 		goto out_unmap;
820 
821 	ret = BLK_STS_IOERR;
822 	if (blk_integrity_rq(req)) {
823 		if (blk_rq_count_integrity_sg(q, req->bio) != 1)
824 			goto out_unmap;
825 
826 		sg_init_table(&iod->meta_sg, 1);
827 		if (blk_rq_map_integrity_sg(q, req->bio, &iod->meta_sg) != 1)
828 			goto out_unmap;
829 
830 		if (req_op(req) == REQ_OP_WRITE)
831 			nvme_dif_remap(req, nvme_dif_prep);
832 
833 		if (!dma_map_sg(dev->dev, &iod->meta_sg, 1, dma_dir))
834 			goto out_unmap;
835 	}
836 
837 	if (blk_integrity_rq(req))
838 		cmnd->rw.metadata = cpu_to_le64(sg_dma_address(&iod->meta_sg));
839 	return BLK_STS_OK;
840 
841 out_unmap:
842 	dma_unmap_sg(dev->dev, iod->sg, iod->nents, dma_dir);
843 out:
844 	return ret;
845 }
846 
847 static void nvme_unmap_data(struct nvme_dev *dev, struct request *req)
848 {
849 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
850 	enum dma_data_direction dma_dir = rq_data_dir(req) ?
851 			DMA_TO_DEVICE : DMA_FROM_DEVICE;
852 
853 	if (iod->nents) {
854 		dma_unmap_sg(dev->dev, iod->sg, iod->nents, dma_dir);
855 		if (blk_integrity_rq(req)) {
856 			if (req_op(req) == REQ_OP_READ)
857 				nvme_dif_remap(req, nvme_dif_complete);
858 			dma_unmap_sg(dev->dev, &iod->meta_sg, 1, dma_dir);
859 		}
860 	}
861 
862 	nvme_cleanup_cmd(req);
863 	nvme_free_iod(dev, req);
864 }
865 
866 /*
867  * NOTE: ns is NULL when called on the admin queue.
868  */
869 static blk_status_t nvme_queue_rq(struct blk_mq_hw_ctx *hctx,
870 			 const struct blk_mq_queue_data *bd)
871 {
872 	struct nvme_ns *ns = hctx->queue->queuedata;
873 	struct nvme_queue *nvmeq = hctx->driver_data;
874 	struct nvme_dev *dev = nvmeq->dev;
875 	struct request *req = bd->rq;
876 	struct nvme_command cmnd;
877 	blk_status_t ret;
878 
879 	/*
880 	 * We should not need to do this, but we're still using this to
881 	 * ensure we can drain requests on a dying queue.
882 	 */
883 	if (unlikely(nvmeq->cq_vector < 0))
884 		return BLK_STS_IOERR;
885 
886 	ret = nvme_setup_cmd(ns, req, &cmnd);
887 	if (ret)
888 		return ret;
889 
890 	ret = nvme_init_iod(req, dev);
891 	if (ret)
892 		goto out_free_cmd;
893 
894 	if (blk_rq_nr_phys_segments(req)) {
895 		ret = nvme_map_data(dev, req, &cmnd);
896 		if (ret)
897 			goto out_cleanup_iod;
898 	}
899 
900 	blk_mq_start_request(req);
901 	nvme_submit_cmd(nvmeq, &cmnd);
902 	return BLK_STS_OK;
903 out_cleanup_iod:
904 	nvme_free_iod(dev, req);
905 out_free_cmd:
906 	nvme_cleanup_cmd(req);
907 	return ret;
908 }
909 
910 static void nvme_pci_complete_rq(struct request *req)
911 {
912 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
913 
914 	nvme_unmap_data(iod->nvmeq->dev, req);
915 	nvme_complete_rq(req);
916 }
917 
918 /* We read the CQE phase first to check if the rest of the entry is valid */
919 static inline bool nvme_cqe_pending(struct nvme_queue *nvmeq)
920 {
921 	return (le16_to_cpu(nvmeq->cqes[nvmeq->cq_head].status) & 1) ==
922 			nvmeq->cq_phase;
923 }
924 
925 static inline void nvme_ring_cq_doorbell(struct nvme_queue *nvmeq)
926 {
927 	u16 head = nvmeq->cq_head;
928 
929 	if (nvme_dbbuf_update_and_check_event(head, nvmeq->dbbuf_cq_db,
930 					      nvmeq->dbbuf_cq_ei))
931 		writel(head, nvmeq->q_db + nvmeq->dev->db_stride);
932 }
933 
934 static inline void nvme_handle_cqe(struct nvme_queue *nvmeq, u16 idx)
935 {
936 	volatile struct nvme_completion *cqe = &nvmeq->cqes[idx];
937 	struct request *req;
938 
939 	if (unlikely(cqe->command_id >= nvmeq->q_depth)) {
940 		dev_warn(nvmeq->dev->ctrl.device,
941 			"invalid id %d completed on queue %d\n",
942 			cqe->command_id, le16_to_cpu(cqe->sq_id));
943 		return;
944 	}
945 
946 	/*
947 	 * AEN requests are special as they don't time out and can
948 	 * survive any kind of queue freeze and often don't respond to
949 	 * aborts.  We don't even bother to allocate a struct request
950 	 * for them but rather special case them here.
951 	 */
952 	if (unlikely(nvmeq->qid == 0 &&
953 			cqe->command_id >= NVME_AQ_BLK_MQ_DEPTH)) {
954 		nvme_complete_async_event(&nvmeq->dev->ctrl,
955 				cqe->status, &cqe->result);
956 		return;
957 	}
958 
959 	req = blk_mq_tag_to_rq(*nvmeq->tags, cqe->command_id);
960 	nvme_end_request(req, cqe->status, cqe->result);
961 }
962 
963 static void nvme_complete_cqes(struct nvme_queue *nvmeq, u16 start, u16 end)
964 {
965 	while (start != end) {
966 		nvme_handle_cqe(nvmeq, start);
967 		if (++start == nvmeq->q_depth)
968 			start = 0;
969 	}
970 }
971 
972 static inline void nvme_update_cq_head(struct nvme_queue *nvmeq)
973 {
974 	if (++nvmeq->cq_head == nvmeq->q_depth) {
975 		nvmeq->cq_head = 0;
976 		nvmeq->cq_phase = !nvmeq->cq_phase;
977 	}
978 }
979 
980 static inline bool nvme_process_cq(struct nvme_queue *nvmeq, u16 *start,
981 		u16 *end, int tag)
982 {
983 	bool found = false;
984 
985 	*start = nvmeq->cq_head;
986 	while (!found && nvme_cqe_pending(nvmeq)) {
987 		if (nvmeq->cqes[nvmeq->cq_head].command_id == tag)
988 			found = true;
989 		nvme_update_cq_head(nvmeq);
990 	}
991 	*end = nvmeq->cq_head;
992 
993 	if (*start != *end)
994 		nvme_ring_cq_doorbell(nvmeq);
995 	return found;
996 }
997 
998 static irqreturn_t nvme_irq(int irq, void *data)
999 {
1000 	struct nvme_queue *nvmeq = data;
1001 	irqreturn_t ret = IRQ_NONE;
1002 	u16 start, end;
1003 
1004 	spin_lock(&nvmeq->cq_lock);
1005 	if (nvmeq->cq_head != nvmeq->last_cq_head)
1006 		ret = IRQ_HANDLED;
1007 	nvme_process_cq(nvmeq, &start, &end, -1);
1008 	nvmeq->last_cq_head = nvmeq->cq_head;
1009 	spin_unlock(&nvmeq->cq_lock);
1010 
1011 	if (start != end) {
1012 		nvme_complete_cqes(nvmeq, start, end);
1013 		return IRQ_HANDLED;
1014 	}
1015 
1016 	return ret;
1017 }
1018 
1019 static irqreturn_t nvme_irq_check(int irq, void *data)
1020 {
1021 	struct nvme_queue *nvmeq = data;
1022 	if (nvme_cqe_pending(nvmeq))
1023 		return IRQ_WAKE_THREAD;
1024 	return IRQ_NONE;
1025 }
1026 
1027 static int __nvme_poll(struct nvme_queue *nvmeq, unsigned int tag)
1028 {
1029 	u16 start, end;
1030 	bool found;
1031 
1032 	if (!nvme_cqe_pending(nvmeq))
1033 		return 0;
1034 
1035 	spin_lock_irq(&nvmeq->cq_lock);
1036 	found = nvme_process_cq(nvmeq, &start, &end, tag);
1037 	spin_unlock_irq(&nvmeq->cq_lock);
1038 
1039 	nvme_complete_cqes(nvmeq, start, end);
1040 	return found;
1041 }
1042 
1043 static int nvme_poll(struct blk_mq_hw_ctx *hctx, unsigned int tag)
1044 {
1045 	struct nvme_queue *nvmeq = hctx->driver_data;
1046 
1047 	return __nvme_poll(nvmeq, tag);
1048 }
1049 
1050 static void nvme_pci_submit_async_event(struct nvme_ctrl *ctrl)
1051 {
1052 	struct nvme_dev *dev = to_nvme_dev(ctrl);
1053 	struct nvme_queue *nvmeq = &dev->queues[0];
1054 	struct nvme_command c;
1055 
1056 	memset(&c, 0, sizeof(c));
1057 	c.common.opcode = nvme_admin_async_event;
1058 	c.common.command_id = NVME_AQ_BLK_MQ_DEPTH;
1059 	nvme_submit_cmd(nvmeq, &c);
1060 }
1061 
1062 static int adapter_delete_queue(struct nvme_dev *dev, u8 opcode, u16 id)
1063 {
1064 	struct nvme_command c;
1065 
1066 	memset(&c, 0, sizeof(c));
1067 	c.delete_queue.opcode = opcode;
1068 	c.delete_queue.qid = cpu_to_le16(id);
1069 
1070 	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1071 }
1072 
1073 static int adapter_alloc_cq(struct nvme_dev *dev, u16 qid,
1074 		struct nvme_queue *nvmeq, s16 vector)
1075 {
1076 	struct nvme_command c;
1077 	int flags = NVME_QUEUE_PHYS_CONTIG | NVME_CQ_IRQ_ENABLED;
1078 
1079 	/*
1080 	 * Note: we (ab)use the fact that the prp fields survive if no data
1081 	 * is attached to the request.
1082 	 */
1083 	memset(&c, 0, sizeof(c));
1084 	c.create_cq.opcode = nvme_admin_create_cq;
1085 	c.create_cq.prp1 = cpu_to_le64(nvmeq->cq_dma_addr);
1086 	c.create_cq.cqid = cpu_to_le16(qid);
1087 	c.create_cq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
1088 	c.create_cq.cq_flags = cpu_to_le16(flags);
1089 	c.create_cq.irq_vector = cpu_to_le16(vector);
1090 
1091 	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1092 }
1093 
1094 static int adapter_alloc_sq(struct nvme_dev *dev, u16 qid,
1095 						struct nvme_queue *nvmeq)
1096 {
1097 	struct nvme_ctrl *ctrl = &dev->ctrl;
1098 	struct nvme_command c;
1099 	int flags = NVME_QUEUE_PHYS_CONTIG;
1100 
1101 	/*
1102 	 * Some drives have a bug that auto-enables WRRU if MEDIUM isn't
1103 	 * set. Since URGENT priority is zeroes, it makes all queues
1104 	 * URGENT.
1105 	 */
1106 	if (ctrl->quirks & NVME_QUIRK_MEDIUM_PRIO_SQ)
1107 		flags |= NVME_SQ_PRIO_MEDIUM;
1108 
1109 	/*
1110 	 * Note: we (ab)use the fact that the prp fields survive if no data
1111 	 * is attached to the request.
1112 	 */
1113 	memset(&c, 0, sizeof(c));
1114 	c.create_sq.opcode = nvme_admin_create_sq;
1115 	c.create_sq.prp1 = cpu_to_le64(nvmeq->sq_dma_addr);
1116 	c.create_sq.sqid = cpu_to_le16(qid);
1117 	c.create_sq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
1118 	c.create_sq.sq_flags = cpu_to_le16(flags);
1119 	c.create_sq.cqid = cpu_to_le16(qid);
1120 
1121 	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1122 }
1123 
1124 static int adapter_delete_cq(struct nvme_dev *dev, u16 cqid)
1125 {
1126 	return adapter_delete_queue(dev, nvme_admin_delete_cq, cqid);
1127 }
1128 
1129 static int adapter_delete_sq(struct nvme_dev *dev, u16 sqid)
1130 {
1131 	return adapter_delete_queue(dev, nvme_admin_delete_sq, sqid);
1132 }
1133 
1134 static void abort_endio(struct request *req, blk_status_t error)
1135 {
1136 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
1137 	struct nvme_queue *nvmeq = iod->nvmeq;
1138 
1139 	dev_warn(nvmeq->dev->ctrl.device,
1140 		 "Abort status: 0x%x", nvme_req(req)->status);
1141 	atomic_inc(&nvmeq->dev->ctrl.abort_limit);
1142 	blk_mq_free_request(req);
1143 }
1144 
1145 static bool nvme_should_reset(struct nvme_dev *dev, u32 csts)
1146 {
1147 
1148 	/* If true, indicates loss of adapter communication, possibly by a
1149 	 * NVMe Subsystem reset.
1150 	 */
1151 	bool nssro = dev->subsystem && (csts & NVME_CSTS_NSSRO);
1152 
1153 	/* If there is a reset/reinit ongoing, we shouldn't reset again. */
1154 	switch (dev->ctrl.state) {
1155 	case NVME_CTRL_RESETTING:
1156 	case NVME_CTRL_CONNECTING:
1157 		return false;
1158 	default:
1159 		break;
1160 	}
1161 
1162 	/* We shouldn't reset unless the controller is on fatal error state
1163 	 * _or_ if we lost the communication with it.
1164 	 */
1165 	if (!(csts & NVME_CSTS_CFS) && !nssro)
1166 		return false;
1167 
1168 	return true;
1169 }
1170 
1171 static void nvme_warn_reset(struct nvme_dev *dev, u32 csts)
1172 {
1173 	/* Read a config register to help see what died. */
1174 	u16 pci_status;
1175 	int result;
1176 
1177 	result = pci_read_config_word(to_pci_dev(dev->dev), PCI_STATUS,
1178 				      &pci_status);
1179 	if (result == PCIBIOS_SUCCESSFUL)
1180 		dev_warn(dev->ctrl.device,
1181 			 "controller is down; will reset: CSTS=0x%x, PCI_STATUS=0x%hx\n",
1182 			 csts, pci_status);
1183 	else
1184 		dev_warn(dev->ctrl.device,
1185 			 "controller is down; will reset: CSTS=0x%x, PCI_STATUS read failed (%d)\n",
1186 			 csts, result);
1187 }
1188 
1189 static enum blk_eh_timer_return nvme_timeout(struct request *req, bool reserved)
1190 {
1191 	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
1192 	struct nvme_queue *nvmeq = iod->nvmeq;
1193 	struct nvme_dev *dev = nvmeq->dev;
1194 	struct request *abort_req;
1195 	struct nvme_command cmd;
1196 	u32 csts = readl(dev->bar + NVME_REG_CSTS);
1197 
1198 	/* If PCI error recovery process is happening, we cannot reset or
1199 	 * the recovery mechanism will surely fail.
1200 	 */
1201 	mb();
1202 	if (pci_channel_offline(to_pci_dev(dev->dev)))
1203 		return BLK_EH_RESET_TIMER;
1204 
1205 	/*
1206 	 * Reset immediately if the controller is failed
1207 	 */
1208 	if (nvme_should_reset(dev, csts)) {
1209 		nvme_warn_reset(dev, csts);
1210 		nvme_dev_disable(dev, false);
1211 		nvme_reset_ctrl(&dev->ctrl);
1212 		return BLK_EH_DONE;
1213 	}
1214 
1215 	/*
1216 	 * Did we miss an interrupt?
1217 	 */
1218 	if (__nvme_poll(nvmeq, req->tag)) {
1219 		dev_warn(dev->ctrl.device,
1220 			 "I/O %d QID %d timeout, completion polled\n",
1221 			 req->tag, nvmeq->qid);
1222 		return BLK_EH_DONE;
1223 	}
1224 
1225 	/*
1226 	 * Shutdown immediately if controller times out while starting. The
1227 	 * reset work will see the pci device disabled when it gets the forced
1228 	 * cancellation error. All outstanding requests are completed on
1229 	 * shutdown, so we return BLK_EH_DONE.
1230 	 */
1231 	switch (dev->ctrl.state) {
1232 	case NVME_CTRL_CONNECTING:
1233 	case NVME_CTRL_RESETTING:
1234 		dev_warn_ratelimited(dev->ctrl.device,
1235 			 "I/O %d QID %d timeout, disable controller\n",
1236 			 req->tag, nvmeq->qid);
1237 		nvme_dev_disable(dev, false);
1238 		nvme_req(req)->flags |= NVME_REQ_CANCELLED;
1239 		return BLK_EH_DONE;
1240 	default:
1241 		break;
1242 	}
1243 
1244 	/*
1245  	 * Shutdown the controller immediately and schedule a reset if the
1246  	 * command was already aborted once before and still hasn't been
1247  	 * returned to the driver, or if this is the admin queue.
1248 	 */
1249 	if (!nvmeq->qid || iod->aborted) {
1250 		dev_warn(dev->ctrl.device,
1251 			 "I/O %d QID %d timeout, reset controller\n",
1252 			 req->tag, nvmeq->qid);
1253 		nvme_dev_disable(dev, false);
1254 		nvme_reset_ctrl(&dev->ctrl);
1255 
1256 		nvme_req(req)->flags |= NVME_REQ_CANCELLED;
1257 		return BLK_EH_DONE;
1258 	}
1259 
1260 	if (atomic_dec_return(&dev->ctrl.abort_limit) < 0) {
1261 		atomic_inc(&dev->ctrl.abort_limit);
1262 		return BLK_EH_RESET_TIMER;
1263 	}
1264 	iod->aborted = 1;
1265 
1266 	memset(&cmd, 0, sizeof(cmd));
1267 	cmd.abort.opcode = nvme_admin_abort_cmd;
1268 	cmd.abort.cid = req->tag;
1269 	cmd.abort.sqid = cpu_to_le16(nvmeq->qid);
1270 
1271 	dev_warn(nvmeq->dev->ctrl.device,
1272 		"I/O %d QID %d timeout, aborting\n",
1273 		 req->tag, nvmeq->qid);
1274 
1275 	abort_req = nvme_alloc_request(dev->ctrl.admin_q, &cmd,
1276 			BLK_MQ_REQ_NOWAIT, NVME_QID_ANY);
1277 	if (IS_ERR(abort_req)) {
1278 		atomic_inc(&dev->ctrl.abort_limit);
1279 		return BLK_EH_RESET_TIMER;
1280 	}
1281 
1282 	abort_req->timeout = ADMIN_TIMEOUT;
1283 	abort_req->end_io_data = NULL;
1284 	blk_execute_rq_nowait(abort_req->q, NULL, abort_req, 0, abort_endio);
1285 
1286 	/*
1287 	 * The aborted req will be completed on receiving the abort req.
1288 	 * We enable the timer again. If hit twice, it'll cause a device reset,
1289 	 * as the device then is in a faulty state.
1290 	 */
1291 	return BLK_EH_RESET_TIMER;
1292 }
1293 
1294 static void nvme_free_queue(struct nvme_queue *nvmeq)
1295 {
1296 	dma_free_coherent(nvmeq->q_dmadev, CQ_SIZE(nvmeq->q_depth),
1297 				(void *)nvmeq->cqes, nvmeq->cq_dma_addr);
1298 	if (nvmeq->sq_cmds)
1299 		dma_free_coherent(nvmeq->q_dmadev, SQ_SIZE(nvmeq->q_depth),
1300 					nvmeq->sq_cmds, nvmeq->sq_dma_addr);
1301 }
1302 
1303 static void nvme_free_queues(struct nvme_dev *dev, int lowest)
1304 {
1305 	int i;
1306 
1307 	for (i = dev->ctrl.queue_count - 1; i >= lowest; i--) {
1308 		dev->ctrl.queue_count--;
1309 		nvme_free_queue(&dev->queues[i]);
1310 	}
1311 }
1312 
1313 /**
1314  * nvme_suspend_queue - put queue into suspended state
1315  * @nvmeq - queue to suspend
1316  */
1317 static int nvme_suspend_queue(struct nvme_queue *nvmeq)
1318 {
1319 	int vector;
1320 
1321 	spin_lock_irq(&nvmeq->cq_lock);
1322 	if (nvmeq->cq_vector == -1) {
1323 		spin_unlock_irq(&nvmeq->cq_lock);
1324 		return 1;
1325 	}
1326 	vector = nvmeq->cq_vector;
1327 	nvmeq->dev->online_queues--;
1328 	nvmeq->cq_vector = -1;
1329 	spin_unlock_irq(&nvmeq->cq_lock);
1330 
1331 	/*
1332 	 * Ensure that nvme_queue_rq() sees it ->cq_vector == -1 without
1333 	 * having to grab the lock.
1334 	 */
1335 	mb();
1336 
1337 	if (!nvmeq->qid && nvmeq->dev->ctrl.admin_q)
1338 		blk_mq_quiesce_queue(nvmeq->dev->ctrl.admin_q);
1339 
1340 	pci_free_irq(to_pci_dev(nvmeq->dev->dev), vector, nvmeq);
1341 
1342 	return 0;
1343 }
1344 
1345 static void nvme_disable_admin_queue(struct nvme_dev *dev, bool shutdown)
1346 {
1347 	struct nvme_queue *nvmeq = &dev->queues[0];
1348 	u16 start, end;
1349 
1350 	if (shutdown)
1351 		nvme_shutdown_ctrl(&dev->ctrl);
1352 	else
1353 		nvme_disable_ctrl(&dev->ctrl, dev->ctrl.cap);
1354 
1355 	spin_lock_irq(&nvmeq->cq_lock);
1356 	nvme_process_cq(nvmeq, &start, &end, -1);
1357 	spin_unlock_irq(&nvmeq->cq_lock);
1358 
1359 	nvme_complete_cqes(nvmeq, start, end);
1360 }
1361 
1362 static int nvme_cmb_qdepth(struct nvme_dev *dev, int nr_io_queues,
1363 				int entry_size)
1364 {
1365 	int q_depth = dev->q_depth;
1366 	unsigned q_size_aligned = roundup(q_depth * entry_size,
1367 					  dev->ctrl.page_size);
1368 
1369 	if (q_size_aligned * nr_io_queues > dev->cmb_size) {
1370 		u64 mem_per_q = div_u64(dev->cmb_size, nr_io_queues);
1371 		mem_per_q = round_down(mem_per_q, dev->ctrl.page_size);
1372 		q_depth = div_u64(mem_per_q, entry_size);
1373 
1374 		/*
1375 		 * Ensure the reduced q_depth is above some threshold where it
1376 		 * would be better to map queues in system memory with the
1377 		 * original depth
1378 		 */
1379 		if (q_depth < 64)
1380 			return -ENOMEM;
1381 	}
1382 
1383 	return q_depth;
1384 }
1385 
1386 static int nvme_alloc_sq_cmds(struct nvme_dev *dev, struct nvme_queue *nvmeq,
1387 				int qid, int depth)
1388 {
1389 	/* CMB SQEs will be mapped before creation */
1390 	if (qid && dev->cmb && use_cmb_sqes && (dev->cmbsz & NVME_CMBSZ_SQS))
1391 		return 0;
1392 
1393 	nvmeq->sq_cmds = dma_alloc_coherent(dev->dev, SQ_SIZE(depth),
1394 					    &nvmeq->sq_dma_addr, GFP_KERNEL);
1395 	if (!nvmeq->sq_cmds)
1396 		return -ENOMEM;
1397 	return 0;
1398 }
1399 
1400 static int nvme_alloc_queue(struct nvme_dev *dev, int qid, int depth)
1401 {
1402 	struct nvme_queue *nvmeq = &dev->queues[qid];
1403 
1404 	if (dev->ctrl.queue_count > qid)
1405 		return 0;
1406 
1407 	nvmeq->cqes = dma_zalloc_coherent(dev->dev, CQ_SIZE(depth),
1408 					  &nvmeq->cq_dma_addr, GFP_KERNEL);
1409 	if (!nvmeq->cqes)
1410 		goto free_nvmeq;
1411 
1412 	if (nvme_alloc_sq_cmds(dev, nvmeq, qid, depth))
1413 		goto free_cqdma;
1414 
1415 	nvmeq->q_dmadev = dev->dev;
1416 	nvmeq->dev = dev;
1417 	spin_lock_init(&nvmeq->sq_lock);
1418 	spin_lock_init(&nvmeq->cq_lock);
1419 	nvmeq->cq_head = 0;
1420 	nvmeq->cq_phase = 1;
1421 	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
1422 	nvmeq->q_depth = depth;
1423 	nvmeq->qid = qid;
1424 	nvmeq->cq_vector = -1;
1425 	dev->ctrl.queue_count++;
1426 
1427 	return 0;
1428 
1429  free_cqdma:
1430 	dma_free_coherent(dev->dev, CQ_SIZE(depth), (void *)nvmeq->cqes,
1431 							nvmeq->cq_dma_addr);
1432  free_nvmeq:
1433 	return -ENOMEM;
1434 }
1435 
1436 static int queue_request_irq(struct nvme_queue *nvmeq)
1437 {
1438 	struct pci_dev *pdev = to_pci_dev(nvmeq->dev->dev);
1439 	int nr = nvmeq->dev->ctrl.instance;
1440 
1441 	if (use_threaded_interrupts) {
1442 		return pci_request_irq(pdev, nvmeq->cq_vector, nvme_irq_check,
1443 				nvme_irq, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
1444 	} else {
1445 		return pci_request_irq(pdev, nvmeq->cq_vector, nvme_irq,
1446 				NULL, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
1447 	}
1448 }
1449 
1450 static void nvme_init_queue(struct nvme_queue *nvmeq, u16 qid)
1451 {
1452 	struct nvme_dev *dev = nvmeq->dev;
1453 
1454 	spin_lock_irq(&nvmeq->cq_lock);
1455 	nvmeq->sq_tail = 0;
1456 	nvmeq->cq_head = 0;
1457 	nvmeq->cq_phase = 1;
1458 	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
1459 	memset((void *)nvmeq->cqes, 0, CQ_SIZE(nvmeq->q_depth));
1460 	nvme_dbbuf_init(dev, nvmeq, qid);
1461 	dev->online_queues++;
1462 	spin_unlock_irq(&nvmeq->cq_lock);
1463 }
1464 
1465 static int nvme_create_queue(struct nvme_queue *nvmeq, int qid)
1466 {
1467 	struct nvme_dev *dev = nvmeq->dev;
1468 	int result;
1469 	s16 vector;
1470 
1471 	if (dev->cmb && use_cmb_sqes && (dev->cmbsz & NVME_CMBSZ_SQS)) {
1472 		unsigned offset = (qid - 1) * roundup(SQ_SIZE(nvmeq->q_depth),
1473 						      dev->ctrl.page_size);
1474 		nvmeq->sq_dma_addr = dev->cmb_bus_addr + offset;
1475 		nvmeq->sq_cmds_io = dev->cmb + offset;
1476 	}
1477 
1478 	/*
1479 	 * A queue's vector matches the queue identifier unless the controller
1480 	 * has only one vector available.
1481 	 */
1482 	vector = dev->num_vecs == 1 ? 0 : qid;
1483 	result = adapter_alloc_cq(dev, qid, nvmeq, vector);
1484 	if (result)
1485 		return result;
1486 
1487 	result = adapter_alloc_sq(dev, qid, nvmeq);
1488 	if (result < 0)
1489 		return result;
1490 	else if (result)
1491 		goto release_cq;
1492 
1493 	/*
1494 	 * Set cq_vector after alloc cq/sq, otherwise nvme_suspend_queue will
1495 	 * invoke free_irq for it and cause a 'Trying to free already-free IRQ
1496 	 * xxx' warning if the create CQ/SQ command times out.
1497 	 */
1498 	nvmeq->cq_vector = vector;
1499 	nvme_init_queue(nvmeq, qid);
1500 	result = queue_request_irq(nvmeq);
1501 	if (result < 0)
1502 		goto release_sq;
1503 
1504 	return result;
1505 
1506 release_sq:
1507 	nvmeq->cq_vector = -1;
1508 	dev->online_queues--;
1509 	adapter_delete_sq(dev, qid);
1510 release_cq:
1511 	adapter_delete_cq(dev, qid);
1512 	return result;
1513 }
1514 
1515 static const struct blk_mq_ops nvme_mq_admin_ops = {
1516 	.queue_rq	= nvme_queue_rq,
1517 	.complete	= nvme_pci_complete_rq,
1518 	.init_hctx	= nvme_admin_init_hctx,
1519 	.exit_hctx      = nvme_admin_exit_hctx,
1520 	.init_request	= nvme_init_request,
1521 	.timeout	= nvme_timeout,
1522 };
1523 
1524 static const struct blk_mq_ops nvme_mq_ops = {
1525 	.queue_rq	= nvme_queue_rq,
1526 	.complete	= nvme_pci_complete_rq,
1527 	.init_hctx	= nvme_init_hctx,
1528 	.init_request	= nvme_init_request,
1529 	.map_queues	= nvme_pci_map_queues,
1530 	.timeout	= nvme_timeout,
1531 	.poll		= nvme_poll,
1532 };
1533 
1534 static void nvme_dev_remove_admin(struct nvme_dev *dev)
1535 {
1536 	if (dev->ctrl.admin_q && !blk_queue_dying(dev->ctrl.admin_q)) {
1537 		/*
1538 		 * If the controller was reset during removal, it's possible
1539 		 * user requests may be waiting on a stopped queue. Start the
1540 		 * queue to flush these to completion.
1541 		 */
1542 		blk_mq_unquiesce_queue(dev->ctrl.admin_q);
1543 		blk_cleanup_queue(dev->ctrl.admin_q);
1544 		blk_mq_free_tag_set(&dev->admin_tagset);
1545 	}
1546 }
1547 
1548 static int nvme_alloc_admin_tags(struct nvme_dev *dev)
1549 {
1550 	if (!dev->ctrl.admin_q) {
1551 		dev->admin_tagset.ops = &nvme_mq_admin_ops;
1552 		dev->admin_tagset.nr_hw_queues = 1;
1553 
1554 		dev->admin_tagset.queue_depth = NVME_AQ_MQ_TAG_DEPTH;
1555 		dev->admin_tagset.timeout = ADMIN_TIMEOUT;
1556 		dev->admin_tagset.numa_node = dev_to_node(dev->dev);
1557 		dev->admin_tagset.cmd_size = nvme_pci_cmd_size(dev, false);
1558 		dev->admin_tagset.flags = BLK_MQ_F_NO_SCHED;
1559 		dev->admin_tagset.driver_data = dev;
1560 
1561 		if (blk_mq_alloc_tag_set(&dev->admin_tagset))
1562 			return -ENOMEM;
1563 		dev->ctrl.admin_tagset = &dev->admin_tagset;
1564 
1565 		dev->ctrl.admin_q = blk_mq_init_queue(&dev->admin_tagset);
1566 		if (IS_ERR(dev->ctrl.admin_q)) {
1567 			blk_mq_free_tag_set(&dev->admin_tagset);
1568 			return -ENOMEM;
1569 		}
1570 		if (!blk_get_queue(dev->ctrl.admin_q)) {
1571 			nvme_dev_remove_admin(dev);
1572 			dev->ctrl.admin_q = NULL;
1573 			return -ENODEV;
1574 		}
1575 	} else
1576 		blk_mq_unquiesce_queue(dev->ctrl.admin_q);
1577 
1578 	return 0;
1579 }
1580 
1581 static unsigned long db_bar_size(struct nvme_dev *dev, unsigned nr_io_queues)
1582 {
1583 	return NVME_REG_DBS + ((nr_io_queues + 1) * 8 * dev->db_stride);
1584 }
1585 
1586 static int nvme_remap_bar(struct nvme_dev *dev, unsigned long size)
1587 {
1588 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1589 
1590 	if (size <= dev->bar_mapped_size)
1591 		return 0;
1592 	if (size > pci_resource_len(pdev, 0))
1593 		return -ENOMEM;
1594 	if (dev->bar)
1595 		iounmap(dev->bar);
1596 	dev->bar = ioremap(pci_resource_start(pdev, 0), size);
1597 	if (!dev->bar) {
1598 		dev->bar_mapped_size = 0;
1599 		return -ENOMEM;
1600 	}
1601 	dev->bar_mapped_size = size;
1602 	dev->dbs = dev->bar + NVME_REG_DBS;
1603 
1604 	return 0;
1605 }
1606 
1607 static int nvme_pci_configure_admin_queue(struct nvme_dev *dev)
1608 {
1609 	int result;
1610 	u32 aqa;
1611 	struct nvme_queue *nvmeq;
1612 
1613 	result = nvme_remap_bar(dev, db_bar_size(dev, 0));
1614 	if (result < 0)
1615 		return result;
1616 
1617 	dev->subsystem = readl(dev->bar + NVME_REG_VS) >= NVME_VS(1, 1, 0) ?
1618 				NVME_CAP_NSSRC(dev->ctrl.cap) : 0;
1619 
1620 	if (dev->subsystem &&
1621 	    (readl(dev->bar + NVME_REG_CSTS) & NVME_CSTS_NSSRO))
1622 		writel(NVME_CSTS_NSSRO, dev->bar + NVME_REG_CSTS);
1623 
1624 	result = nvme_disable_ctrl(&dev->ctrl, dev->ctrl.cap);
1625 	if (result < 0)
1626 		return result;
1627 
1628 	result = nvme_alloc_queue(dev, 0, NVME_AQ_DEPTH);
1629 	if (result)
1630 		return result;
1631 
1632 	nvmeq = &dev->queues[0];
1633 	aqa = nvmeq->q_depth - 1;
1634 	aqa |= aqa << 16;
1635 
1636 	writel(aqa, dev->bar + NVME_REG_AQA);
1637 	lo_hi_writeq(nvmeq->sq_dma_addr, dev->bar + NVME_REG_ASQ);
1638 	lo_hi_writeq(nvmeq->cq_dma_addr, dev->bar + NVME_REG_ACQ);
1639 
1640 	result = nvme_enable_ctrl(&dev->ctrl, dev->ctrl.cap);
1641 	if (result)
1642 		return result;
1643 
1644 	nvmeq->cq_vector = 0;
1645 	nvme_init_queue(nvmeq, 0);
1646 	result = queue_request_irq(nvmeq);
1647 	if (result) {
1648 		nvmeq->cq_vector = -1;
1649 		return result;
1650 	}
1651 
1652 	return result;
1653 }
1654 
1655 static int nvme_create_io_queues(struct nvme_dev *dev)
1656 {
1657 	unsigned i, max;
1658 	int ret = 0;
1659 
1660 	for (i = dev->ctrl.queue_count; i <= dev->max_qid; i++) {
1661 		if (nvme_alloc_queue(dev, i, dev->q_depth)) {
1662 			ret = -ENOMEM;
1663 			break;
1664 		}
1665 	}
1666 
1667 	max = min(dev->max_qid, dev->ctrl.queue_count - 1);
1668 	for (i = dev->online_queues; i <= max; i++) {
1669 		ret = nvme_create_queue(&dev->queues[i], i);
1670 		if (ret)
1671 			break;
1672 	}
1673 
1674 	/*
1675 	 * Ignore failing Create SQ/CQ commands, we can continue with less
1676 	 * than the desired amount of queues, and even a controller without
1677 	 * I/O queues can still be used to issue admin commands.  This might
1678 	 * be useful to upgrade a buggy firmware for example.
1679 	 */
1680 	return ret >= 0 ? 0 : ret;
1681 }
1682 
1683 static ssize_t nvme_cmb_show(struct device *dev,
1684 			     struct device_attribute *attr,
1685 			     char *buf)
1686 {
1687 	struct nvme_dev *ndev = to_nvme_dev(dev_get_drvdata(dev));
1688 
1689 	return scnprintf(buf, PAGE_SIZE, "cmbloc : x%08x\ncmbsz  : x%08x\n",
1690 		       ndev->cmbloc, ndev->cmbsz);
1691 }
1692 static DEVICE_ATTR(cmb, S_IRUGO, nvme_cmb_show, NULL);
1693 
1694 static u64 nvme_cmb_size_unit(struct nvme_dev *dev)
1695 {
1696 	u8 szu = (dev->cmbsz >> NVME_CMBSZ_SZU_SHIFT) & NVME_CMBSZ_SZU_MASK;
1697 
1698 	return 1ULL << (12 + 4 * szu);
1699 }
1700 
1701 static u32 nvme_cmb_size(struct nvme_dev *dev)
1702 {
1703 	return (dev->cmbsz >> NVME_CMBSZ_SZ_SHIFT) & NVME_CMBSZ_SZ_MASK;
1704 }
1705 
1706 static void nvme_map_cmb(struct nvme_dev *dev)
1707 {
1708 	u64 size, offset;
1709 	resource_size_t bar_size;
1710 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1711 	int bar;
1712 
1713 	dev->cmbsz = readl(dev->bar + NVME_REG_CMBSZ);
1714 	if (!dev->cmbsz)
1715 		return;
1716 	dev->cmbloc = readl(dev->bar + NVME_REG_CMBLOC);
1717 
1718 	if (!use_cmb_sqes)
1719 		return;
1720 
1721 	size = nvme_cmb_size_unit(dev) * nvme_cmb_size(dev);
1722 	offset = nvme_cmb_size_unit(dev) * NVME_CMB_OFST(dev->cmbloc);
1723 	bar = NVME_CMB_BIR(dev->cmbloc);
1724 	bar_size = pci_resource_len(pdev, bar);
1725 
1726 	if (offset > bar_size)
1727 		return;
1728 
1729 	/*
1730 	 * Controllers may support a CMB size larger than their BAR,
1731 	 * for example, due to being behind a bridge. Reduce the CMB to
1732 	 * the reported size of the BAR
1733 	 */
1734 	if (size > bar_size - offset)
1735 		size = bar_size - offset;
1736 
1737 	dev->cmb = ioremap_wc(pci_resource_start(pdev, bar) + offset, size);
1738 	if (!dev->cmb)
1739 		return;
1740 	dev->cmb_bus_addr = pci_bus_address(pdev, bar) + offset;
1741 	dev->cmb_size = size;
1742 
1743 	if (sysfs_add_file_to_group(&dev->ctrl.device->kobj,
1744 				    &dev_attr_cmb.attr, NULL))
1745 		dev_warn(dev->ctrl.device,
1746 			 "failed to add sysfs attribute for CMB\n");
1747 }
1748 
1749 static inline void nvme_release_cmb(struct nvme_dev *dev)
1750 {
1751 	if (dev->cmb) {
1752 		iounmap(dev->cmb);
1753 		dev->cmb = NULL;
1754 		sysfs_remove_file_from_group(&dev->ctrl.device->kobj,
1755 					     &dev_attr_cmb.attr, NULL);
1756 		dev->cmbsz = 0;
1757 	}
1758 }
1759 
1760 static int nvme_set_host_mem(struct nvme_dev *dev, u32 bits)
1761 {
1762 	u64 dma_addr = dev->host_mem_descs_dma;
1763 	struct nvme_command c;
1764 	int ret;
1765 
1766 	memset(&c, 0, sizeof(c));
1767 	c.features.opcode	= nvme_admin_set_features;
1768 	c.features.fid		= cpu_to_le32(NVME_FEAT_HOST_MEM_BUF);
1769 	c.features.dword11	= cpu_to_le32(bits);
1770 	c.features.dword12	= cpu_to_le32(dev->host_mem_size >>
1771 					      ilog2(dev->ctrl.page_size));
1772 	c.features.dword13	= cpu_to_le32(lower_32_bits(dma_addr));
1773 	c.features.dword14	= cpu_to_le32(upper_32_bits(dma_addr));
1774 	c.features.dword15	= cpu_to_le32(dev->nr_host_mem_descs);
1775 
1776 	ret = nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1777 	if (ret) {
1778 		dev_warn(dev->ctrl.device,
1779 			 "failed to set host mem (err %d, flags %#x).\n",
1780 			 ret, bits);
1781 	}
1782 	return ret;
1783 }
1784 
1785 static void nvme_free_host_mem(struct nvme_dev *dev)
1786 {
1787 	int i;
1788 
1789 	for (i = 0; i < dev->nr_host_mem_descs; i++) {
1790 		struct nvme_host_mem_buf_desc *desc = &dev->host_mem_descs[i];
1791 		size_t size = le32_to_cpu(desc->size) * dev->ctrl.page_size;
1792 
1793 		dma_free_coherent(dev->dev, size, dev->host_mem_desc_bufs[i],
1794 				le64_to_cpu(desc->addr));
1795 	}
1796 
1797 	kfree(dev->host_mem_desc_bufs);
1798 	dev->host_mem_desc_bufs = NULL;
1799 	dma_free_coherent(dev->dev,
1800 			dev->nr_host_mem_descs * sizeof(*dev->host_mem_descs),
1801 			dev->host_mem_descs, dev->host_mem_descs_dma);
1802 	dev->host_mem_descs = NULL;
1803 	dev->nr_host_mem_descs = 0;
1804 }
1805 
1806 static int __nvme_alloc_host_mem(struct nvme_dev *dev, u64 preferred,
1807 		u32 chunk_size)
1808 {
1809 	struct nvme_host_mem_buf_desc *descs;
1810 	u32 max_entries, len;
1811 	dma_addr_t descs_dma;
1812 	int i = 0;
1813 	void **bufs;
1814 	u64 size, tmp;
1815 
1816 	tmp = (preferred + chunk_size - 1);
1817 	do_div(tmp, chunk_size);
1818 	max_entries = tmp;
1819 
1820 	if (dev->ctrl.hmmaxd && dev->ctrl.hmmaxd < max_entries)
1821 		max_entries = dev->ctrl.hmmaxd;
1822 
1823 	descs = dma_zalloc_coherent(dev->dev, max_entries * sizeof(*descs),
1824 			&descs_dma, GFP_KERNEL);
1825 	if (!descs)
1826 		goto out;
1827 
1828 	bufs = kcalloc(max_entries, sizeof(*bufs), GFP_KERNEL);
1829 	if (!bufs)
1830 		goto out_free_descs;
1831 
1832 	for (size = 0; size < preferred && i < max_entries; size += len) {
1833 		dma_addr_t dma_addr;
1834 
1835 		len = min_t(u64, chunk_size, preferred - size);
1836 		bufs[i] = dma_alloc_attrs(dev->dev, len, &dma_addr, GFP_KERNEL,
1837 				DMA_ATTR_NO_KERNEL_MAPPING | DMA_ATTR_NO_WARN);
1838 		if (!bufs[i])
1839 			break;
1840 
1841 		descs[i].addr = cpu_to_le64(dma_addr);
1842 		descs[i].size = cpu_to_le32(len / dev->ctrl.page_size);
1843 		i++;
1844 	}
1845 
1846 	if (!size)
1847 		goto out_free_bufs;
1848 
1849 	dev->nr_host_mem_descs = i;
1850 	dev->host_mem_size = size;
1851 	dev->host_mem_descs = descs;
1852 	dev->host_mem_descs_dma = descs_dma;
1853 	dev->host_mem_desc_bufs = bufs;
1854 	return 0;
1855 
1856 out_free_bufs:
1857 	while (--i >= 0) {
1858 		size_t size = le32_to_cpu(descs[i].size) * dev->ctrl.page_size;
1859 
1860 		dma_free_coherent(dev->dev, size, bufs[i],
1861 				le64_to_cpu(descs[i].addr));
1862 	}
1863 
1864 	kfree(bufs);
1865 out_free_descs:
1866 	dma_free_coherent(dev->dev, max_entries * sizeof(*descs), descs,
1867 			descs_dma);
1868 out:
1869 	dev->host_mem_descs = NULL;
1870 	return -ENOMEM;
1871 }
1872 
1873 static int nvme_alloc_host_mem(struct nvme_dev *dev, u64 min, u64 preferred)
1874 {
1875 	u32 chunk_size;
1876 
1877 	/* start big and work our way down */
1878 	for (chunk_size = min_t(u64, preferred, PAGE_SIZE * MAX_ORDER_NR_PAGES);
1879 	     chunk_size >= max_t(u32, dev->ctrl.hmminds * 4096, PAGE_SIZE * 2);
1880 	     chunk_size /= 2) {
1881 		if (!__nvme_alloc_host_mem(dev, preferred, chunk_size)) {
1882 			if (!min || dev->host_mem_size >= min)
1883 				return 0;
1884 			nvme_free_host_mem(dev);
1885 		}
1886 	}
1887 
1888 	return -ENOMEM;
1889 }
1890 
1891 static int nvme_setup_host_mem(struct nvme_dev *dev)
1892 {
1893 	u64 max = (u64)max_host_mem_size_mb * SZ_1M;
1894 	u64 preferred = (u64)dev->ctrl.hmpre * 4096;
1895 	u64 min = (u64)dev->ctrl.hmmin * 4096;
1896 	u32 enable_bits = NVME_HOST_MEM_ENABLE;
1897 	int ret;
1898 
1899 	preferred = min(preferred, max);
1900 	if (min > max) {
1901 		dev_warn(dev->ctrl.device,
1902 			"min host memory (%lld MiB) above limit (%d MiB).\n",
1903 			min >> ilog2(SZ_1M), max_host_mem_size_mb);
1904 		nvme_free_host_mem(dev);
1905 		return 0;
1906 	}
1907 
1908 	/*
1909 	 * If we already have a buffer allocated check if we can reuse it.
1910 	 */
1911 	if (dev->host_mem_descs) {
1912 		if (dev->host_mem_size >= min)
1913 			enable_bits |= NVME_HOST_MEM_RETURN;
1914 		else
1915 			nvme_free_host_mem(dev);
1916 	}
1917 
1918 	if (!dev->host_mem_descs) {
1919 		if (nvme_alloc_host_mem(dev, min, preferred)) {
1920 			dev_warn(dev->ctrl.device,
1921 				"failed to allocate host memory buffer.\n");
1922 			return 0; /* controller must work without HMB */
1923 		}
1924 
1925 		dev_info(dev->ctrl.device,
1926 			"allocated %lld MiB host memory buffer.\n",
1927 			dev->host_mem_size >> ilog2(SZ_1M));
1928 	}
1929 
1930 	ret = nvme_set_host_mem(dev, enable_bits);
1931 	if (ret)
1932 		nvme_free_host_mem(dev);
1933 	return ret;
1934 }
1935 
1936 static int nvme_setup_io_queues(struct nvme_dev *dev)
1937 {
1938 	struct nvme_queue *adminq = &dev->queues[0];
1939 	struct pci_dev *pdev = to_pci_dev(dev->dev);
1940 	int result, nr_io_queues;
1941 	unsigned long size;
1942 
1943 	struct irq_affinity affd = {
1944 		.pre_vectors = 1
1945 	};
1946 
1947 	nr_io_queues = num_possible_cpus();
1948 	result = nvme_set_queue_count(&dev->ctrl, &nr_io_queues);
1949 	if (result < 0)
1950 		return result;
1951 
1952 	if (nr_io_queues == 0)
1953 		return 0;
1954 
1955 	if (dev->cmb && (dev->cmbsz & NVME_CMBSZ_SQS)) {
1956 		result = nvme_cmb_qdepth(dev, nr_io_queues,
1957 				sizeof(struct nvme_command));
1958 		if (result > 0)
1959 			dev->q_depth = result;
1960 		else
1961 			nvme_release_cmb(dev);
1962 	}
1963 
1964 	do {
1965 		size = db_bar_size(dev, nr_io_queues);
1966 		result = nvme_remap_bar(dev, size);
1967 		if (!result)
1968 			break;
1969 		if (!--nr_io_queues)
1970 			return -ENOMEM;
1971 	} while (1);
1972 	adminq->q_db = dev->dbs;
1973 
1974 	/* Deregister the admin queue's interrupt */
1975 	pci_free_irq(pdev, 0, adminq);
1976 
1977 	/*
1978 	 * If we enable msix early due to not intx, disable it again before
1979 	 * setting up the full range we need.
1980 	 */
1981 	pci_free_irq_vectors(pdev);
1982 	result = pci_alloc_irq_vectors_affinity(pdev, 1, nr_io_queues + 1,
1983 			PCI_IRQ_ALL_TYPES | PCI_IRQ_AFFINITY, &affd);
1984 	if (result <= 0)
1985 		return -EIO;
1986 	dev->num_vecs = result;
1987 	dev->max_qid = max(result - 1, 1);
1988 
1989 	/*
1990 	 * Should investigate if there's a performance win from allocating
1991 	 * more queues than interrupt vectors; it might allow the submission
1992 	 * path to scale better, even if the receive path is limited by the
1993 	 * number of interrupts.
1994 	 */
1995 
1996 	result = queue_request_irq(adminq);
1997 	if (result) {
1998 		adminq->cq_vector = -1;
1999 		return result;
2000 	}
2001 	return nvme_create_io_queues(dev);
2002 }
2003 
2004 static void nvme_del_queue_end(struct request *req, blk_status_t error)
2005 {
2006 	struct nvme_queue *nvmeq = req->end_io_data;
2007 
2008 	blk_mq_free_request(req);
2009 	complete(&nvmeq->dev->ioq_wait);
2010 }
2011 
2012 static void nvme_del_cq_end(struct request *req, blk_status_t error)
2013 {
2014 	struct nvme_queue *nvmeq = req->end_io_data;
2015 	u16 start, end;
2016 
2017 	if (!error) {
2018 		unsigned long flags;
2019 
2020 		spin_lock_irqsave(&nvmeq->cq_lock, flags);
2021 		nvme_process_cq(nvmeq, &start, &end, -1);
2022 		spin_unlock_irqrestore(&nvmeq->cq_lock, flags);
2023 
2024 		nvme_complete_cqes(nvmeq, start, end);
2025 	}
2026 
2027 	nvme_del_queue_end(req, error);
2028 }
2029 
2030 static int nvme_delete_queue(struct nvme_queue *nvmeq, u8 opcode)
2031 {
2032 	struct request_queue *q = nvmeq->dev->ctrl.admin_q;
2033 	struct request *req;
2034 	struct nvme_command cmd;
2035 
2036 	memset(&cmd, 0, sizeof(cmd));
2037 	cmd.delete_queue.opcode = opcode;
2038 	cmd.delete_queue.qid = cpu_to_le16(nvmeq->qid);
2039 
2040 	req = nvme_alloc_request(q, &cmd, BLK_MQ_REQ_NOWAIT, NVME_QID_ANY);
2041 	if (IS_ERR(req))
2042 		return PTR_ERR(req);
2043 
2044 	req->timeout = ADMIN_TIMEOUT;
2045 	req->end_io_data = nvmeq;
2046 
2047 	blk_execute_rq_nowait(q, NULL, req, false,
2048 			opcode == nvme_admin_delete_cq ?
2049 				nvme_del_cq_end : nvme_del_queue_end);
2050 	return 0;
2051 }
2052 
2053 static void nvme_disable_io_queues(struct nvme_dev *dev)
2054 {
2055 	int pass, queues = dev->online_queues - 1;
2056 	unsigned long timeout;
2057 	u8 opcode = nvme_admin_delete_sq;
2058 
2059 	for (pass = 0; pass < 2; pass++) {
2060 		int sent = 0, i = queues;
2061 
2062 		reinit_completion(&dev->ioq_wait);
2063  retry:
2064 		timeout = ADMIN_TIMEOUT;
2065 		for (; i > 0; i--, sent++)
2066 			if (nvme_delete_queue(&dev->queues[i], opcode))
2067 				break;
2068 
2069 		while (sent--) {
2070 			timeout = wait_for_completion_io_timeout(&dev->ioq_wait, timeout);
2071 			if (timeout == 0)
2072 				return;
2073 			if (i)
2074 				goto retry;
2075 		}
2076 		opcode = nvme_admin_delete_cq;
2077 	}
2078 }
2079 
2080 /*
2081  * return error value only when tagset allocation failed
2082  */
2083 static int nvme_dev_add(struct nvme_dev *dev)
2084 {
2085 	int ret;
2086 
2087 	if (!dev->ctrl.tagset) {
2088 		dev->tagset.ops = &nvme_mq_ops;
2089 		dev->tagset.nr_hw_queues = dev->online_queues - 1;
2090 		dev->tagset.timeout = NVME_IO_TIMEOUT;
2091 		dev->tagset.numa_node = dev_to_node(dev->dev);
2092 		dev->tagset.queue_depth =
2093 				min_t(int, dev->q_depth, BLK_MQ_MAX_DEPTH) - 1;
2094 		dev->tagset.cmd_size = nvme_pci_cmd_size(dev, false);
2095 		if ((dev->ctrl.sgls & ((1 << 0) | (1 << 1))) && sgl_threshold) {
2096 			dev->tagset.cmd_size = max(dev->tagset.cmd_size,
2097 					nvme_pci_cmd_size(dev, true));
2098 		}
2099 		dev->tagset.flags = BLK_MQ_F_SHOULD_MERGE;
2100 		dev->tagset.driver_data = dev;
2101 
2102 		ret = blk_mq_alloc_tag_set(&dev->tagset);
2103 		if (ret) {
2104 			dev_warn(dev->ctrl.device,
2105 				"IO queues tagset allocation failed %d\n", ret);
2106 			return ret;
2107 		}
2108 		dev->ctrl.tagset = &dev->tagset;
2109 
2110 		nvme_dbbuf_set(dev);
2111 	} else {
2112 		blk_mq_update_nr_hw_queues(&dev->tagset, dev->online_queues - 1);
2113 
2114 		/* Free previously allocated queues that are no longer usable */
2115 		nvme_free_queues(dev, dev->online_queues);
2116 	}
2117 
2118 	return 0;
2119 }
2120 
2121 static int nvme_pci_enable(struct nvme_dev *dev)
2122 {
2123 	int result = -ENOMEM;
2124 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2125 
2126 	if (pci_enable_device_mem(pdev))
2127 		return result;
2128 
2129 	pci_set_master(pdev);
2130 
2131 	if (dma_set_mask_and_coherent(dev->dev, DMA_BIT_MASK(64)) &&
2132 	    dma_set_mask_and_coherent(dev->dev, DMA_BIT_MASK(32)))
2133 		goto disable;
2134 
2135 	if (readl(dev->bar + NVME_REG_CSTS) == -1) {
2136 		result = -ENODEV;
2137 		goto disable;
2138 	}
2139 
2140 	/*
2141 	 * Some devices and/or platforms don't advertise or work with INTx
2142 	 * interrupts. Pre-enable a single MSIX or MSI vec for setup. We'll
2143 	 * adjust this later.
2144 	 */
2145 	result = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
2146 	if (result < 0)
2147 		return result;
2148 
2149 	dev->ctrl.cap = lo_hi_readq(dev->bar + NVME_REG_CAP);
2150 
2151 	dev->q_depth = min_t(int, NVME_CAP_MQES(dev->ctrl.cap) + 1,
2152 				io_queue_depth);
2153 	dev->db_stride = 1 << NVME_CAP_STRIDE(dev->ctrl.cap);
2154 	dev->dbs = dev->bar + 4096;
2155 
2156 	/*
2157 	 * Temporary fix for the Apple controller found in the MacBook8,1 and
2158 	 * some MacBook7,1 to avoid controller resets and data loss.
2159 	 */
2160 	if (pdev->vendor == PCI_VENDOR_ID_APPLE && pdev->device == 0x2001) {
2161 		dev->q_depth = 2;
2162 		dev_warn(dev->ctrl.device, "detected Apple NVMe controller, "
2163 			"set queue depth=%u to work around controller resets\n",
2164 			dev->q_depth);
2165 	} else if (pdev->vendor == PCI_VENDOR_ID_SAMSUNG &&
2166 		   (pdev->device == 0xa821 || pdev->device == 0xa822) &&
2167 		   NVME_CAP_MQES(dev->ctrl.cap) == 0) {
2168 		dev->q_depth = 64;
2169 		dev_err(dev->ctrl.device, "detected PM1725 NVMe controller, "
2170                         "set queue depth=%u\n", dev->q_depth);
2171 	}
2172 
2173 	nvme_map_cmb(dev);
2174 
2175 	pci_enable_pcie_error_reporting(pdev);
2176 	pci_save_state(pdev);
2177 	return 0;
2178 
2179  disable:
2180 	pci_disable_device(pdev);
2181 	return result;
2182 }
2183 
2184 static void nvme_dev_unmap(struct nvme_dev *dev)
2185 {
2186 	if (dev->bar)
2187 		iounmap(dev->bar);
2188 	pci_release_mem_regions(to_pci_dev(dev->dev));
2189 }
2190 
2191 static void nvme_pci_disable(struct nvme_dev *dev)
2192 {
2193 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2194 
2195 	nvme_release_cmb(dev);
2196 	pci_free_irq_vectors(pdev);
2197 
2198 	if (pci_is_enabled(pdev)) {
2199 		pci_disable_pcie_error_reporting(pdev);
2200 		pci_disable_device(pdev);
2201 	}
2202 }
2203 
2204 static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown)
2205 {
2206 	int i;
2207 	bool dead = true;
2208 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2209 
2210 	mutex_lock(&dev->shutdown_lock);
2211 	if (pci_is_enabled(pdev)) {
2212 		u32 csts = readl(dev->bar + NVME_REG_CSTS);
2213 
2214 		if (dev->ctrl.state == NVME_CTRL_LIVE ||
2215 		    dev->ctrl.state == NVME_CTRL_RESETTING)
2216 			nvme_start_freeze(&dev->ctrl);
2217 		dead = !!((csts & NVME_CSTS_CFS) || !(csts & NVME_CSTS_RDY) ||
2218 			pdev->error_state  != pci_channel_io_normal);
2219 	}
2220 
2221 	/*
2222 	 * Give the controller a chance to complete all entered requests if
2223 	 * doing a safe shutdown.
2224 	 */
2225 	if (!dead) {
2226 		if (shutdown)
2227 			nvme_wait_freeze_timeout(&dev->ctrl, NVME_IO_TIMEOUT);
2228 	}
2229 
2230 	nvme_stop_queues(&dev->ctrl);
2231 
2232 	if (!dead && dev->ctrl.queue_count > 0) {
2233 		nvme_disable_io_queues(dev);
2234 		nvme_disable_admin_queue(dev, shutdown);
2235 	}
2236 	for (i = dev->ctrl.queue_count - 1; i >= 0; i--)
2237 		nvme_suspend_queue(&dev->queues[i]);
2238 
2239 	nvme_pci_disable(dev);
2240 
2241 	blk_mq_tagset_busy_iter(&dev->tagset, nvme_cancel_request, &dev->ctrl);
2242 	blk_mq_tagset_busy_iter(&dev->admin_tagset, nvme_cancel_request, &dev->ctrl);
2243 
2244 	/*
2245 	 * The driver will not be starting up queues again if shutting down so
2246 	 * must flush all entered requests to their failed completion to avoid
2247 	 * deadlocking blk-mq hot-cpu notifier.
2248 	 */
2249 	if (shutdown)
2250 		nvme_start_queues(&dev->ctrl);
2251 	mutex_unlock(&dev->shutdown_lock);
2252 }
2253 
2254 static int nvme_setup_prp_pools(struct nvme_dev *dev)
2255 {
2256 	dev->prp_page_pool = dma_pool_create("prp list page", dev->dev,
2257 						PAGE_SIZE, PAGE_SIZE, 0);
2258 	if (!dev->prp_page_pool)
2259 		return -ENOMEM;
2260 
2261 	/* Optimisation for I/Os between 4k and 128k */
2262 	dev->prp_small_pool = dma_pool_create("prp list 256", dev->dev,
2263 						256, 256, 0);
2264 	if (!dev->prp_small_pool) {
2265 		dma_pool_destroy(dev->prp_page_pool);
2266 		return -ENOMEM;
2267 	}
2268 	return 0;
2269 }
2270 
2271 static void nvme_release_prp_pools(struct nvme_dev *dev)
2272 {
2273 	dma_pool_destroy(dev->prp_page_pool);
2274 	dma_pool_destroy(dev->prp_small_pool);
2275 }
2276 
2277 static void nvme_pci_free_ctrl(struct nvme_ctrl *ctrl)
2278 {
2279 	struct nvme_dev *dev = to_nvme_dev(ctrl);
2280 
2281 	nvme_dbbuf_dma_free(dev);
2282 	put_device(dev->dev);
2283 	if (dev->tagset.tags)
2284 		blk_mq_free_tag_set(&dev->tagset);
2285 	if (dev->ctrl.admin_q)
2286 		blk_put_queue(dev->ctrl.admin_q);
2287 	kfree(dev->queues);
2288 	free_opal_dev(dev->ctrl.opal_dev);
2289 	mempool_destroy(dev->iod_mempool);
2290 	kfree(dev);
2291 }
2292 
2293 static void nvme_remove_dead_ctrl(struct nvme_dev *dev, int status)
2294 {
2295 	dev_warn(dev->ctrl.device, "Removing after probe failure status: %d\n", status);
2296 
2297 	nvme_get_ctrl(&dev->ctrl);
2298 	nvme_dev_disable(dev, false);
2299 	nvme_kill_queues(&dev->ctrl);
2300 	if (!queue_work(nvme_wq, &dev->remove_work))
2301 		nvme_put_ctrl(&dev->ctrl);
2302 }
2303 
2304 static void nvme_reset_work(struct work_struct *work)
2305 {
2306 	struct nvme_dev *dev =
2307 		container_of(work, struct nvme_dev, ctrl.reset_work);
2308 	bool was_suspend = !!(dev->ctrl.ctrl_config & NVME_CC_SHN_NORMAL);
2309 	int result = -ENODEV;
2310 	enum nvme_ctrl_state new_state = NVME_CTRL_LIVE;
2311 
2312 	if (WARN_ON(dev->ctrl.state != NVME_CTRL_RESETTING))
2313 		goto out;
2314 
2315 	/*
2316 	 * If we're called to reset a live controller first shut it down before
2317 	 * moving on.
2318 	 */
2319 	if (dev->ctrl.ctrl_config & NVME_CC_ENABLE)
2320 		nvme_dev_disable(dev, false);
2321 
2322 	/*
2323 	 * Introduce CONNECTING state from nvme-fc/rdma transports to mark the
2324 	 * initializing procedure here.
2325 	 */
2326 	if (!nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_CONNECTING)) {
2327 		dev_warn(dev->ctrl.device,
2328 			"failed to mark controller CONNECTING\n");
2329 		goto out;
2330 	}
2331 
2332 	result = nvme_pci_enable(dev);
2333 	if (result)
2334 		goto out;
2335 
2336 	result = nvme_pci_configure_admin_queue(dev);
2337 	if (result)
2338 		goto out;
2339 
2340 	result = nvme_alloc_admin_tags(dev);
2341 	if (result)
2342 		goto out;
2343 
2344 	/*
2345 	 * Limit the max command size to prevent iod->sg allocations going
2346 	 * over a single page.
2347 	 */
2348 	dev->ctrl.max_hw_sectors = NVME_MAX_KB_SZ << 1;
2349 	dev->ctrl.max_segments = NVME_MAX_SEGS;
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 	if (pci_get_drvdata(pdev))
2424 		device_release_driver(&pdev->dev);
2425 	nvme_put_ctrl(&dev->ctrl);
2426 }
2427 
2428 static int nvme_pci_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val)
2429 {
2430 	*val = readl(to_nvme_dev(ctrl)->bar + off);
2431 	return 0;
2432 }
2433 
2434 static int nvme_pci_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val)
2435 {
2436 	writel(val, to_nvme_dev(ctrl)->bar + off);
2437 	return 0;
2438 }
2439 
2440 static int nvme_pci_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val)
2441 {
2442 	*val = readq(to_nvme_dev(ctrl)->bar + off);
2443 	return 0;
2444 }
2445 
2446 static int nvme_pci_get_address(struct nvme_ctrl *ctrl, char *buf, int size)
2447 {
2448 	struct pci_dev *pdev = to_pci_dev(to_nvme_dev(ctrl)->dev);
2449 
2450 	return snprintf(buf, size, "%s", dev_name(&pdev->dev));
2451 }
2452 
2453 static const struct nvme_ctrl_ops nvme_pci_ctrl_ops = {
2454 	.name			= "pcie",
2455 	.module			= THIS_MODULE,
2456 	.flags			= NVME_F_METADATA_SUPPORTED,
2457 	.reg_read32		= nvme_pci_reg_read32,
2458 	.reg_write32		= nvme_pci_reg_write32,
2459 	.reg_read64		= nvme_pci_reg_read64,
2460 	.free_ctrl		= nvme_pci_free_ctrl,
2461 	.submit_async_event	= nvme_pci_submit_async_event,
2462 	.get_address		= nvme_pci_get_address,
2463 };
2464 
2465 static int nvme_dev_map(struct nvme_dev *dev)
2466 {
2467 	struct pci_dev *pdev = to_pci_dev(dev->dev);
2468 
2469 	if (pci_request_mem_regions(pdev, "nvme"))
2470 		return -ENODEV;
2471 
2472 	if (nvme_remap_bar(dev, NVME_REG_DBS + 4096))
2473 		goto release;
2474 
2475 	return 0;
2476   release:
2477 	pci_release_mem_regions(pdev);
2478 	return -ENODEV;
2479 }
2480 
2481 static unsigned long check_vendor_combination_bug(struct pci_dev *pdev)
2482 {
2483 	if (pdev->vendor == 0x144d && pdev->device == 0xa802) {
2484 		/*
2485 		 * Several Samsung devices seem to drop off the PCIe bus
2486 		 * randomly when APST is on and uses the deepest sleep state.
2487 		 * This has been observed on a Samsung "SM951 NVMe SAMSUNG
2488 		 * 256GB", a "PM951 NVMe SAMSUNG 512GB", and a "Samsung SSD
2489 		 * 950 PRO 256GB", but it seems to be restricted to two Dell
2490 		 * laptops.
2491 		 */
2492 		if (dmi_match(DMI_SYS_VENDOR, "Dell Inc.") &&
2493 		    (dmi_match(DMI_PRODUCT_NAME, "XPS 15 9550") ||
2494 		     dmi_match(DMI_PRODUCT_NAME, "Precision 5510")))
2495 			return NVME_QUIRK_NO_DEEPEST_PS;
2496 	} else if (pdev->vendor == 0x144d && pdev->device == 0xa804) {
2497 		/*
2498 		 * Samsung SSD 960 EVO drops off the PCIe bus after system
2499 		 * suspend on a Ryzen board, ASUS PRIME B350M-A, as well as
2500 		 * within few minutes after bootup on a Coffee Lake board -
2501 		 * ASUS PRIME Z370-A
2502 		 */
2503 		if (dmi_match(DMI_BOARD_VENDOR, "ASUSTeK COMPUTER INC.") &&
2504 		    (dmi_match(DMI_BOARD_NAME, "PRIME B350M-A") ||
2505 		     dmi_match(DMI_BOARD_NAME, "PRIME Z370-A")))
2506 			return NVME_QUIRK_NO_APST;
2507 	}
2508 
2509 	return 0;
2510 }
2511 
2512 static void nvme_async_probe(void *data, async_cookie_t cookie)
2513 {
2514 	struct nvme_dev *dev = data;
2515 
2516 	nvme_reset_ctrl_sync(&dev->ctrl);
2517 	flush_work(&dev->ctrl.scan_work);
2518 	nvme_put_ctrl(&dev->ctrl);
2519 }
2520 
2521 static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
2522 {
2523 	int node, result = -ENOMEM;
2524 	struct nvme_dev *dev;
2525 	unsigned long quirks = id->driver_data;
2526 	size_t alloc_size;
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 	/*
2560 	 * Double check that our mempool alloc size will cover the biggest
2561 	 * command we support.
2562 	 */
2563 	alloc_size = nvme_pci_iod_alloc_size(dev, NVME_MAX_KB_SZ,
2564 						NVME_MAX_SEGS, true);
2565 	WARN_ON_ONCE(alloc_size > PAGE_SIZE);
2566 
2567 	dev->iod_mempool = mempool_create_node(1, mempool_kmalloc,
2568 						mempool_kfree,
2569 						(void *) alloc_size,
2570 						GFP_KERNEL, node);
2571 	if (!dev->iod_mempool) {
2572 		result = -ENOMEM;
2573 		goto release_pools;
2574 	}
2575 
2576 	result = nvme_init_ctrl(&dev->ctrl, &pdev->dev, &nvme_pci_ctrl_ops,
2577 			quirks);
2578 	if (result)
2579 		goto release_mempool;
2580 
2581 	dev_info(dev->ctrl.device, "pci function %s\n", dev_name(&pdev->dev));
2582 
2583 	nvme_get_ctrl(&dev->ctrl);
2584 	async_schedule(nvme_async_probe, dev);
2585 
2586 	return 0;
2587 
2588  release_mempool:
2589 	mempool_destroy(dev->iod_mempool);
2590  release_pools:
2591 	nvme_release_prp_pools(dev);
2592  unmap:
2593 	nvme_dev_unmap(dev);
2594  put_pci:
2595 	put_device(dev->dev);
2596  free:
2597 	kfree(dev->queues);
2598 	kfree(dev);
2599 	return result;
2600 }
2601 
2602 static void nvme_reset_prepare(struct pci_dev *pdev)
2603 {
2604 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2605 	nvme_dev_disable(dev, false);
2606 }
2607 
2608 static void nvme_reset_done(struct pci_dev *pdev)
2609 {
2610 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2611 	nvme_reset_ctrl_sync(&dev->ctrl);
2612 }
2613 
2614 static void nvme_shutdown(struct pci_dev *pdev)
2615 {
2616 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2617 	nvme_dev_disable(dev, true);
2618 }
2619 
2620 /*
2621  * The driver's remove may be called on a device in a partially initialized
2622  * state. This function must not have any dependencies on the device state in
2623  * order to proceed.
2624  */
2625 static void nvme_remove(struct pci_dev *pdev)
2626 {
2627 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2628 
2629 	nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DELETING);
2630 
2631 	cancel_work_sync(&dev->ctrl.reset_work);
2632 	pci_set_drvdata(pdev, NULL);
2633 
2634 	if (!pci_device_is_present(pdev)) {
2635 		nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DEAD);
2636 		nvme_dev_disable(dev, true);
2637 	}
2638 
2639 	flush_work(&dev->ctrl.reset_work);
2640 	nvme_stop_ctrl(&dev->ctrl);
2641 	nvme_remove_namespaces(&dev->ctrl);
2642 	nvme_dev_disable(dev, true);
2643 	nvme_free_host_mem(dev);
2644 	nvme_dev_remove_admin(dev);
2645 	nvme_free_queues(dev, 0);
2646 	nvme_uninit_ctrl(&dev->ctrl);
2647 	nvme_release_prp_pools(dev);
2648 	nvme_dev_unmap(dev);
2649 	nvme_put_ctrl(&dev->ctrl);
2650 }
2651 
2652 #ifdef CONFIG_PM_SLEEP
2653 static int nvme_suspend(struct device *dev)
2654 {
2655 	struct pci_dev *pdev = to_pci_dev(dev);
2656 	struct nvme_dev *ndev = pci_get_drvdata(pdev);
2657 
2658 	nvme_dev_disable(ndev, true);
2659 	return 0;
2660 }
2661 
2662 static int nvme_resume(struct device *dev)
2663 {
2664 	struct pci_dev *pdev = to_pci_dev(dev);
2665 	struct nvme_dev *ndev = pci_get_drvdata(pdev);
2666 
2667 	nvme_reset_ctrl(&ndev->ctrl);
2668 	return 0;
2669 }
2670 #endif
2671 
2672 static SIMPLE_DEV_PM_OPS(nvme_dev_pm_ops, nvme_suspend, nvme_resume);
2673 
2674 static pci_ers_result_t nvme_error_detected(struct pci_dev *pdev,
2675 						pci_channel_state_t state)
2676 {
2677 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2678 
2679 	/*
2680 	 * A frozen channel requires a reset. When detected, this method will
2681 	 * shutdown the controller to quiesce. The controller will be restarted
2682 	 * after the slot reset through driver's slot_reset callback.
2683 	 */
2684 	switch (state) {
2685 	case pci_channel_io_normal:
2686 		return PCI_ERS_RESULT_CAN_RECOVER;
2687 	case pci_channel_io_frozen:
2688 		dev_warn(dev->ctrl.device,
2689 			"frozen state error detected, reset controller\n");
2690 		nvme_dev_disable(dev, false);
2691 		return PCI_ERS_RESULT_NEED_RESET;
2692 	case pci_channel_io_perm_failure:
2693 		dev_warn(dev->ctrl.device,
2694 			"failure state error detected, request disconnect\n");
2695 		return PCI_ERS_RESULT_DISCONNECT;
2696 	}
2697 	return PCI_ERS_RESULT_NEED_RESET;
2698 }
2699 
2700 static pci_ers_result_t nvme_slot_reset(struct pci_dev *pdev)
2701 {
2702 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2703 
2704 	dev_info(dev->ctrl.device, "restart after slot reset\n");
2705 	pci_restore_state(pdev);
2706 	nvme_reset_ctrl(&dev->ctrl);
2707 	return PCI_ERS_RESULT_RECOVERED;
2708 }
2709 
2710 static void nvme_error_resume(struct pci_dev *pdev)
2711 {
2712 	struct nvme_dev *dev = pci_get_drvdata(pdev);
2713 
2714 	flush_work(&dev->ctrl.reset_work);
2715 	pci_cleanup_aer_uncorrect_error_status(pdev);
2716 }
2717 
2718 static const struct pci_error_handlers nvme_err_handler = {
2719 	.error_detected	= nvme_error_detected,
2720 	.slot_reset	= nvme_slot_reset,
2721 	.resume		= nvme_error_resume,
2722 	.reset_prepare	= nvme_reset_prepare,
2723 	.reset_done	= nvme_reset_done,
2724 };
2725 
2726 static const struct pci_device_id nvme_id_table[] = {
2727 	{ PCI_VDEVICE(INTEL, 0x0953),
2728 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
2729 				NVME_QUIRK_DEALLOCATE_ZEROES, },
2730 	{ PCI_VDEVICE(INTEL, 0x0a53),
2731 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
2732 				NVME_QUIRK_DEALLOCATE_ZEROES, },
2733 	{ PCI_VDEVICE(INTEL, 0x0a54),
2734 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
2735 				NVME_QUIRK_DEALLOCATE_ZEROES, },
2736 	{ PCI_VDEVICE(INTEL, 0x0a55),
2737 		.driver_data = NVME_QUIRK_STRIPE_SIZE |
2738 				NVME_QUIRK_DEALLOCATE_ZEROES, },
2739 	{ PCI_VDEVICE(INTEL, 0xf1a5),	/* Intel 600P/P3100 */
2740 		.driver_data = NVME_QUIRK_NO_DEEPEST_PS |
2741 				NVME_QUIRK_MEDIUM_PRIO_SQ },
2742 	{ PCI_VDEVICE(INTEL, 0x5845),	/* Qemu emulated controller */
2743 		.driver_data = NVME_QUIRK_IDENTIFY_CNS, },
2744 	{ PCI_DEVICE(0x1bb1, 0x0100),   /* Seagate Nytro Flash Storage */
2745 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2746 	{ PCI_DEVICE(0x1c58, 0x0003),	/* HGST adapter */
2747 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2748 	{ PCI_DEVICE(0x1c58, 0x0023),	/* WDC SN200 adapter */
2749 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2750 	{ PCI_DEVICE(0x1c5f, 0x0540),	/* Memblaze Pblaze4 adapter */
2751 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2752 	{ PCI_DEVICE(0x144d, 0xa821),   /* Samsung PM1725 */
2753 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2754 	{ PCI_DEVICE(0x144d, 0xa822),   /* Samsung PM1725a */
2755 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
2756 	{ PCI_DEVICE(0x1d1d, 0x1f1f),	/* LighNVM qemu device */
2757 		.driver_data = NVME_QUIRK_LIGHTNVM, },
2758 	{ PCI_DEVICE(0x1d1d, 0x2807),	/* CNEX WL */
2759 		.driver_data = NVME_QUIRK_LIGHTNVM, },
2760 	{ PCI_DEVICE(0x1d1d, 0x2601),	/* CNEX Granby */
2761 		.driver_data = NVME_QUIRK_LIGHTNVM, },
2762 	{ PCI_DEVICE_CLASS(PCI_CLASS_STORAGE_EXPRESS, 0xffffff) },
2763 	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2001) },
2764 	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2003) },
2765 	{ 0, }
2766 };
2767 MODULE_DEVICE_TABLE(pci, nvme_id_table);
2768 
2769 static struct pci_driver nvme_driver = {
2770 	.name		= "nvme",
2771 	.id_table	= nvme_id_table,
2772 	.probe		= nvme_probe,
2773 	.remove		= nvme_remove,
2774 	.shutdown	= nvme_shutdown,
2775 	.driver		= {
2776 		.pm	= &nvme_dev_pm_ops,
2777 	},
2778 	.sriov_configure = pci_sriov_configure_simple,
2779 	.err_handler	= &nvme_err_handler,
2780 };
2781 
2782 static int __init nvme_init(void)
2783 {
2784 	return pci_register_driver(&nvme_driver);
2785 }
2786 
2787 static void __exit nvme_exit(void)
2788 {
2789 	pci_unregister_driver(&nvme_driver);
2790 	flush_workqueue(nvme_wq);
2791 	_nvme_check_size();
2792 }
2793 
2794 MODULE_AUTHOR("Matthew Wilcox <willy@linux.intel.com>");
2795 MODULE_LICENSE("GPL");
2796 MODULE_VERSION("1.0");
2797 module_init(nvme_init);
2798 module_exit(nvme_exit);
2799