xref: /kernel/linux/linux-5.10/drivers/nvme/host/pci.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * NVM Express device driver
4 * Copyright (c) 2011-2014, Intel Corporation.
5 */
6
7#include <linux/acpi.h>
8#include <linux/aer.h>
9#include <linux/async.h>
10#include <linux/blkdev.h>
11#include <linux/blk-mq.h>
12#include <linux/blk-mq-pci.h>
13#include <linux/dmi.h>
14#include <linux/init.h>
15#include <linux/interrupt.h>
16#include <linux/io.h>
17#include <linux/mm.h>
18#include <linux/module.h>
19#include <linux/mutex.h>
20#include <linux/once.h>
21#include <linux/pci.h>
22#include <linux/suspend.h>
23#include <linux/t10-pi.h>
24#include <linux/types.h>
25#include <linux/io-64-nonatomic-lo-hi.h>
26#include <linux/io-64-nonatomic-hi-lo.h>
27#include <linux/sed-opal.h>
28#include <linux/pci-p2pdma.h>
29
30#include "trace.h"
31#include "nvme.h"
32
33#define SQ_SIZE(q)	((q)->q_depth << (q)->sqes)
34#define CQ_SIZE(q)	((q)->q_depth * sizeof(struct nvme_completion))
35
36#define SGES_PER_PAGE	(NVME_CTRL_PAGE_SIZE / sizeof(struct nvme_sgl_desc))
37
38/*
39 * These can be higher, but we need to ensure that any command doesn't
40 * require an sg allocation that needs more than a page of data.
41 */
42#define NVME_MAX_KB_SZ	4096
43#define NVME_MAX_SEGS	127
44
45static int use_threaded_interrupts;
46module_param(use_threaded_interrupts, int, 0);
47
48static bool use_cmb_sqes = true;
49module_param(use_cmb_sqes, bool, 0444);
50MODULE_PARM_DESC(use_cmb_sqes, "use controller's memory buffer for I/O SQes");
51
52static unsigned int max_host_mem_size_mb = 128;
53module_param(max_host_mem_size_mb, uint, 0444);
54MODULE_PARM_DESC(max_host_mem_size_mb,
55	"Maximum Host Memory Buffer (HMB) size per controller (in MiB)");
56
57static unsigned int sgl_threshold = SZ_32K;
58module_param(sgl_threshold, uint, 0644);
59MODULE_PARM_DESC(sgl_threshold,
60		"Use SGLs when average request segment size is larger or equal to "
61		"this size. Use 0 to disable SGLs.");
62
63static int io_queue_depth_set(const char *val, const struct kernel_param *kp);
64static const struct kernel_param_ops io_queue_depth_ops = {
65	.set = io_queue_depth_set,
66	.get = param_get_uint,
67};
68
69static unsigned int io_queue_depth = 1024;
70module_param_cb(io_queue_depth, &io_queue_depth_ops, &io_queue_depth, 0644);
71MODULE_PARM_DESC(io_queue_depth, "set io queue depth, should >= 2");
72
73static int io_queue_count_set(const char *val, const struct kernel_param *kp)
74{
75	unsigned int n;
76	int ret;
77
78	ret = kstrtouint(val, 10, &n);
79	if (ret != 0 || n > num_possible_cpus())
80		return -EINVAL;
81	return param_set_uint(val, kp);
82}
83
84static const struct kernel_param_ops io_queue_count_ops = {
85	.set = io_queue_count_set,
86	.get = param_get_uint,
87};
88
89static unsigned int write_queues;
90module_param_cb(write_queues, &io_queue_count_ops, &write_queues, 0644);
91MODULE_PARM_DESC(write_queues,
92	"Number of queues to use for writes. If not set, reads and writes "
93	"will share a queue set.");
94
95static unsigned int poll_queues;
96module_param_cb(poll_queues, &io_queue_count_ops, &poll_queues, 0644);
97MODULE_PARM_DESC(poll_queues, "Number of queues to use for polled IO.");
98
99static bool noacpi;
100module_param(noacpi, bool, 0444);
101MODULE_PARM_DESC(noacpi, "disable acpi bios quirks");
102
103struct nvme_dev;
104struct nvme_queue;
105
106static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown);
107static bool __nvme_disable_io_queues(struct nvme_dev *dev, u8 opcode);
108
109/*
110 * Represents an NVM Express device.  Each nvme_dev is a PCI function.
111 */
112struct nvme_dev {
113	struct nvme_queue *queues;
114	struct blk_mq_tag_set tagset;
115	struct blk_mq_tag_set admin_tagset;
116	u32 __iomem *dbs;
117	struct device *dev;
118	struct dma_pool *prp_page_pool;
119	struct dma_pool *prp_small_pool;
120	unsigned online_queues;
121	unsigned max_qid;
122	unsigned io_queues[HCTX_MAX_TYPES];
123	unsigned int num_vecs;
124	u32 q_depth;
125	int io_sqes;
126	u32 db_stride;
127	void __iomem *bar;
128	unsigned long bar_mapped_size;
129	struct work_struct remove_work;
130	struct mutex shutdown_lock;
131	bool subsystem;
132	u64 cmb_size;
133	bool cmb_use_sqes;
134	u32 cmbsz;
135	u32 cmbloc;
136	struct nvme_ctrl ctrl;
137	u32 last_ps;
138
139	mempool_t *iod_mempool;
140
141	/* shadow doorbell buffer support: */
142	__le32 *dbbuf_dbs;
143	dma_addr_t dbbuf_dbs_dma_addr;
144	__le32 *dbbuf_eis;
145	dma_addr_t dbbuf_eis_dma_addr;
146
147	/* host memory buffer support: */
148	u64 host_mem_size;
149	u32 nr_host_mem_descs;
150	dma_addr_t host_mem_descs_dma;
151	struct nvme_host_mem_buf_desc *host_mem_descs;
152	void **host_mem_desc_bufs;
153	unsigned int nr_allocated_queues;
154	unsigned int nr_write_queues;
155	unsigned int nr_poll_queues;
156};
157
158static int io_queue_depth_set(const char *val, const struct kernel_param *kp)
159{
160	int ret;
161	u32 n;
162
163	ret = kstrtou32(val, 10, &n);
164	if (ret != 0 || n < 2)
165		return -EINVAL;
166
167	return param_set_uint(val, kp);
168}
169
170static inline unsigned int sq_idx(unsigned int qid, u32 stride)
171{
172	return qid * 2 * stride;
173}
174
175static inline unsigned int cq_idx(unsigned int qid, u32 stride)
176{
177	return (qid * 2 + 1) * stride;
178}
179
180static inline struct nvme_dev *to_nvme_dev(struct nvme_ctrl *ctrl)
181{
182	return container_of(ctrl, struct nvme_dev, ctrl);
183}
184
185/*
186 * An NVM Express queue.  Each device has at least two (one for admin
187 * commands and one for I/O commands).
188 */
189struct nvme_queue {
190	struct nvme_dev *dev;
191	spinlock_t sq_lock;
192	void *sq_cmds;
193	 /* only used for poll queues: */
194	spinlock_t cq_poll_lock ____cacheline_aligned_in_smp;
195	struct nvme_completion *cqes;
196	dma_addr_t sq_dma_addr;
197	dma_addr_t cq_dma_addr;
198	u32 __iomem *q_db;
199	u32 q_depth;
200	u16 cq_vector;
201	u16 sq_tail;
202	u16 last_sq_tail;
203	u16 cq_head;
204	u16 qid;
205	u8 cq_phase;
206	u8 sqes;
207	unsigned long flags;
208#define NVMEQ_ENABLED		0
209#define NVMEQ_SQ_CMB		1
210#define NVMEQ_DELETE_ERROR	2
211#define NVMEQ_POLLED		3
212	__le32 *dbbuf_sq_db;
213	__le32 *dbbuf_cq_db;
214	__le32 *dbbuf_sq_ei;
215	__le32 *dbbuf_cq_ei;
216	struct completion delete_done;
217};
218
219/*
220 * The nvme_iod describes the data in an I/O.
221 *
222 * The sg pointer contains the list of PRP/SGL chunk allocations in addition
223 * to the actual struct scatterlist.
224 */
225struct nvme_iod {
226	struct nvme_request req;
227	struct nvme_command cmd;
228	struct nvme_queue *nvmeq;
229	bool use_sgl;
230	int aborted;
231	int npages;		/* In the PRP list. 0 means small pool in use */
232	int nents;		/* Used in scatterlist */
233	dma_addr_t first_dma;
234	unsigned int dma_len;	/* length of single DMA segment mapping */
235	dma_addr_t meta_dma;
236	struct scatterlist *sg;
237};
238
239static inline unsigned int nvme_dbbuf_size(struct nvme_dev *dev)
240{
241	return dev->nr_allocated_queues * 8 * dev->db_stride;
242}
243
244static int nvme_dbbuf_dma_alloc(struct nvme_dev *dev)
245{
246	unsigned int mem_size = nvme_dbbuf_size(dev);
247
248	if (dev->dbbuf_dbs)
249		return 0;
250
251	dev->dbbuf_dbs = dma_alloc_coherent(dev->dev, mem_size,
252					    &dev->dbbuf_dbs_dma_addr,
253					    GFP_KERNEL);
254	if (!dev->dbbuf_dbs)
255		return -ENOMEM;
256	dev->dbbuf_eis = dma_alloc_coherent(dev->dev, mem_size,
257					    &dev->dbbuf_eis_dma_addr,
258					    GFP_KERNEL);
259	if (!dev->dbbuf_eis) {
260		dma_free_coherent(dev->dev, mem_size,
261				  dev->dbbuf_dbs, dev->dbbuf_dbs_dma_addr);
262		dev->dbbuf_dbs = NULL;
263		return -ENOMEM;
264	}
265
266	return 0;
267}
268
269static void nvme_dbbuf_dma_free(struct nvme_dev *dev)
270{
271	unsigned int mem_size = nvme_dbbuf_size(dev);
272
273	if (dev->dbbuf_dbs) {
274		dma_free_coherent(dev->dev, mem_size,
275				  dev->dbbuf_dbs, dev->dbbuf_dbs_dma_addr);
276		dev->dbbuf_dbs = NULL;
277	}
278	if (dev->dbbuf_eis) {
279		dma_free_coherent(dev->dev, mem_size,
280				  dev->dbbuf_eis, dev->dbbuf_eis_dma_addr);
281		dev->dbbuf_eis = NULL;
282	}
283}
284
285static void nvme_dbbuf_init(struct nvme_dev *dev,
286			    struct nvme_queue *nvmeq, int qid)
287{
288	if (!dev->dbbuf_dbs || !qid)
289		return;
290
291	nvmeq->dbbuf_sq_db = &dev->dbbuf_dbs[sq_idx(qid, dev->db_stride)];
292	nvmeq->dbbuf_cq_db = &dev->dbbuf_dbs[cq_idx(qid, dev->db_stride)];
293	nvmeq->dbbuf_sq_ei = &dev->dbbuf_eis[sq_idx(qid, dev->db_stride)];
294	nvmeq->dbbuf_cq_ei = &dev->dbbuf_eis[cq_idx(qid, dev->db_stride)];
295}
296
297static void nvme_dbbuf_free(struct nvme_queue *nvmeq)
298{
299	if (!nvmeq->qid)
300		return;
301
302	nvmeq->dbbuf_sq_db = NULL;
303	nvmeq->dbbuf_cq_db = NULL;
304	nvmeq->dbbuf_sq_ei = NULL;
305	nvmeq->dbbuf_cq_ei = NULL;
306}
307
308static void nvme_dbbuf_set(struct nvme_dev *dev)
309{
310	struct nvme_command c;
311	unsigned int i;
312
313	if (!dev->dbbuf_dbs)
314		return;
315
316	memset(&c, 0, sizeof(c));
317	c.dbbuf.opcode = nvme_admin_dbbuf;
318	c.dbbuf.prp1 = cpu_to_le64(dev->dbbuf_dbs_dma_addr);
319	c.dbbuf.prp2 = cpu_to_le64(dev->dbbuf_eis_dma_addr);
320
321	if (nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0)) {
322		dev_warn(dev->ctrl.device, "unable to set dbbuf\n");
323		/* Free memory and continue on */
324		nvme_dbbuf_dma_free(dev);
325
326		for (i = 1; i <= dev->online_queues; i++)
327			nvme_dbbuf_free(&dev->queues[i]);
328	}
329}
330
331static inline int nvme_dbbuf_need_event(u16 event_idx, u16 new_idx, u16 old)
332{
333	return (u16)(new_idx - event_idx - 1) < (u16)(new_idx - old);
334}
335
336/* Update dbbuf and return true if an MMIO is required */
337static bool nvme_dbbuf_update_and_check_event(u16 value, __le32 *dbbuf_db,
338					      volatile __le32 *dbbuf_ei)
339{
340	if (dbbuf_db) {
341		u16 old_value, event_idx;
342
343		/*
344		 * Ensure that the queue is written before updating
345		 * the doorbell in memory
346		 */
347		wmb();
348
349		old_value = le32_to_cpu(*dbbuf_db);
350		*dbbuf_db = cpu_to_le32(value);
351
352		/*
353		 * Ensure that the doorbell is updated before reading the event
354		 * index from memory.  The controller needs to provide similar
355		 * ordering to ensure the envent index is updated before reading
356		 * the doorbell.
357		 */
358		mb();
359
360		event_idx = le32_to_cpu(*dbbuf_ei);
361		if (!nvme_dbbuf_need_event(event_idx, value, old_value))
362			return false;
363	}
364
365	return true;
366}
367
368/*
369 * Will slightly overestimate the number of pages needed.  This is OK
370 * as it only leads to a small amount of wasted memory for the lifetime of
371 * the I/O.
372 */
373static int nvme_pci_npages_prp(void)
374{
375	unsigned max_bytes = (NVME_MAX_KB_SZ * 1024) + NVME_CTRL_PAGE_SIZE;
376	unsigned nprps = DIV_ROUND_UP(max_bytes, NVME_CTRL_PAGE_SIZE);
377	return DIV_ROUND_UP(8 * nprps, NVME_CTRL_PAGE_SIZE - 8);
378}
379
380/*
381 * Calculates the number of pages needed for the SGL segments. For example a 4k
382 * page can accommodate 256 SGL descriptors.
383 */
384static int nvme_pci_npages_sgl(void)
385{
386	return DIV_ROUND_UP(NVME_MAX_SEGS * sizeof(struct nvme_sgl_desc),
387			NVME_CTRL_PAGE_SIZE);
388}
389
390static int nvme_admin_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
391				unsigned int hctx_idx)
392{
393	struct nvme_dev *dev = data;
394	struct nvme_queue *nvmeq = &dev->queues[0];
395
396	WARN_ON(hctx_idx != 0);
397	WARN_ON(dev->admin_tagset.tags[0] != hctx->tags);
398
399	hctx->driver_data = nvmeq;
400	return 0;
401}
402
403static int nvme_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
404			  unsigned int hctx_idx)
405{
406	struct nvme_dev *dev = data;
407	struct nvme_queue *nvmeq = &dev->queues[hctx_idx + 1];
408
409	WARN_ON(dev->tagset.tags[hctx_idx] != hctx->tags);
410	hctx->driver_data = nvmeq;
411	return 0;
412}
413
414static int nvme_init_request(struct blk_mq_tag_set *set, struct request *req,
415		unsigned int hctx_idx, unsigned int numa_node)
416{
417	struct nvme_dev *dev = set->driver_data;
418	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
419	int queue_idx = (set == &dev->tagset) ? hctx_idx + 1 : 0;
420	struct nvme_queue *nvmeq = &dev->queues[queue_idx];
421
422	BUG_ON(!nvmeq);
423	iod->nvmeq = nvmeq;
424
425	nvme_req(req)->ctrl = &dev->ctrl;
426	return 0;
427}
428
429static int queue_irq_offset(struct nvme_dev *dev)
430{
431	/* if we have more than 1 vec, admin queue offsets us by 1 */
432	if (dev->num_vecs > 1)
433		return 1;
434
435	return 0;
436}
437
438static int nvme_pci_map_queues(struct blk_mq_tag_set *set)
439{
440	struct nvme_dev *dev = set->driver_data;
441	int i, qoff, offset;
442
443	offset = queue_irq_offset(dev);
444	for (i = 0, qoff = 0; i < set->nr_maps; i++) {
445		struct blk_mq_queue_map *map = &set->map[i];
446
447		map->nr_queues = dev->io_queues[i];
448		if (!map->nr_queues) {
449			BUG_ON(i == HCTX_TYPE_DEFAULT);
450			continue;
451		}
452
453		/*
454		 * The poll queue(s) doesn't have an IRQ (and hence IRQ
455		 * affinity), so use the regular blk-mq cpu mapping
456		 */
457		map->queue_offset = qoff;
458		if (i != HCTX_TYPE_POLL && offset)
459			blk_mq_pci_map_queues(map, to_pci_dev(dev->dev), offset);
460		else
461			blk_mq_map_queues(map);
462		qoff += map->nr_queues;
463		offset += map->nr_queues;
464	}
465
466	return 0;
467}
468
469/*
470 * Write sq tail if we are asked to, or if the next command would wrap.
471 */
472static inline void nvme_write_sq_db(struct nvme_queue *nvmeq, bool write_sq)
473{
474	if (!write_sq) {
475		u16 next_tail = nvmeq->sq_tail + 1;
476
477		if (next_tail == nvmeq->q_depth)
478			next_tail = 0;
479		if (next_tail != nvmeq->last_sq_tail)
480			return;
481	}
482
483	if (nvme_dbbuf_update_and_check_event(nvmeq->sq_tail,
484			nvmeq->dbbuf_sq_db, nvmeq->dbbuf_sq_ei))
485		writel(nvmeq->sq_tail, nvmeq->q_db);
486	nvmeq->last_sq_tail = nvmeq->sq_tail;
487}
488
489/**
490 * nvme_submit_cmd() - Copy a command into a queue and ring the doorbell
491 * @nvmeq: The queue to use
492 * @cmd: The command to send
493 * @write_sq: whether to write to the SQ doorbell
494 */
495static void nvme_submit_cmd(struct nvme_queue *nvmeq, struct nvme_command *cmd,
496			    bool write_sq)
497{
498	spin_lock(&nvmeq->sq_lock);
499	memcpy(nvmeq->sq_cmds + (nvmeq->sq_tail << nvmeq->sqes),
500	       cmd, sizeof(*cmd));
501	if (++nvmeq->sq_tail == nvmeq->q_depth)
502		nvmeq->sq_tail = 0;
503	nvme_write_sq_db(nvmeq, write_sq);
504	spin_unlock(&nvmeq->sq_lock);
505}
506
507static void nvme_commit_rqs(struct blk_mq_hw_ctx *hctx)
508{
509	struct nvme_queue *nvmeq = hctx->driver_data;
510
511	spin_lock(&nvmeq->sq_lock);
512	if (nvmeq->sq_tail != nvmeq->last_sq_tail)
513		nvme_write_sq_db(nvmeq, true);
514	spin_unlock(&nvmeq->sq_lock);
515}
516
517static void **nvme_pci_iod_list(struct request *req)
518{
519	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
520	return (void **)(iod->sg + blk_rq_nr_phys_segments(req));
521}
522
523static inline bool nvme_pci_use_sgls(struct nvme_dev *dev, struct request *req)
524{
525	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
526	int nseg = blk_rq_nr_phys_segments(req);
527	unsigned int avg_seg_size;
528
529	avg_seg_size = DIV_ROUND_UP(blk_rq_payload_bytes(req), nseg);
530
531	if (!(dev->ctrl.sgls & ((1 << 0) | (1 << 1))))
532		return false;
533	if (!iod->nvmeq->qid)
534		return false;
535	if (!sgl_threshold || avg_seg_size < sgl_threshold)
536		return false;
537	return true;
538}
539
540static void nvme_free_prps(struct nvme_dev *dev, struct request *req)
541{
542	const int last_prp = NVME_CTRL_PAGE_SIZE / sizeof(__le64) - 1;
543	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
544	dma_addr_t dma_addr = iod->first_dma;
545	int i;
546
547	for (i = 0; i < iod->npages; i++) {
548		__le64 *prp_list = nvme_pci_iod_list(req)[i];
549		dma_addr_t next_dma_addr = le64_to_cpu(prp_list[last_prp]);
550
551		dma_pool_free(dev->prp_page_pool, prp_list, dma_addr);
552		dma_addr = next_dma_addr;
553	}
554
555}
556
557static void nvme_free_sgls(struct nvme_dev *dev, struct request *req)
558{
559	const int last_sg = SGES_PER_PAGE - 1;
560	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
561	dma_addr_t dma_addr = iod->first_dma;
562	int i;
563
564	for (i = 0; i < iod->npages; i++) {
565		struct nvme_sgl_desc *sg_list = nvme_pci_iod_list(req)[i];
566		dma_addr_t next_dma_addr = le64_to_cpu((sg_list[last_sg]).addr);
567
568		dma_pool_free(dev->prp_page_pool, sg_list, dma_addr);
569		dma_addr = next_dma_addr;
570	}
571
572}
573
574static void nvme_unmap_sg(struct nvme_dev *dev, struct request *req)
575{
576	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
577
578	if (is_pci_p2pdma_page(sg_page(iod->sg)))
579		pci_p2pdma_unmap_sg(dev->dev, iod->sg, iod->nents,
580				    rq_dma_dir(req));
581	else
582		dma_unmap_sg(dev->dev, iod->sg, iod->nents, rq_dma_dir(req));
583}
584
585static void nvme_unmap_data(struct nvme_dev *dev, struct request *req)
586{
587	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
588
589	if (iod->dma_len) {
590		dma_unmap_page(dev->dev, iod->first_dma, iod->dma_len,
591			       rq_dma_dir(req));
592		return;
593	}
594
595	WARN_ON_ONCE(!iod->nents);
596
597	nvme_unmap_sg(dev, req);
598	if (iod->npages == 0)
599		dma_pool_free(dev->prp_small_pool, nvme_pci_iod_list(req)[0],
600			      iod->first_dma);
601	else if (iod->use_sgl)
602		nvme_free_sgls(dev, req);
603	else
604		nvme_free_prps(dev, req);
605	mempool_free(iod->sg, dev->iod_mempool);
606}
607
608static void nvme_print_sgl(struct scatterlist *sgl, int nents)
609{
610	int i;
611	struct scatterlist *sg;
612
613	for_each_sg(sgl, sg, nents, i) {
614		dma_addr_t phys = sg_phys(sg);
615		pr_warn("sg[%d] phys_addr:%pad offset:%d length:%d "
616			"dma_address:%pad dma_length:%d\n",
617			i, &phys, sg->offset, sg->length, &sg_dma_address(sg),
618			sg_dma_len(sg));
619	}
620}
621
622static blk_status_t nvme_pci_setup_prps(struct nvme_dev *dev,
623		struct request *req, struct nvme_rw_command *cmnd)
624{
625	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
626	struct dma_pool *pool;
627	int length = blk_rq_payload_bytes(req);
628	struct scatterlist *sg = iod->sg;
629	int dma_len = sg_dma_len(sg);
630	u64 dma_addr = sg_dma_address(sg);
631	int offset = dma_addr & (NVME_CTRL_PAGE_SIZE - 1);
632	__le64 *prp_list;
633	void **list = nvme_pci_iod_list(req);
634	dma_addr_t prp_dma;
635	int nprps, i;
636
637	length -= (NVME_CTRL_PAGE_SIZE - offset);
638	if (length <= 0) {
639		iod->first_dma = 0;
640		goto done;
641	}
642
643	dma_len -= (NVME_CTRL_PAGE_SIZE - offset);
644	if (dma_len) {
645		dma_addr += (NVME_CTRL_PAGE_SIZE - offset);
646	} else {
647		sg = sg_next(sg);
648		dma_addr = sg_dma_address(sg);
649		dma_len = sg_dma_len(sg);
650	}
651
652	if (length <= NVME_CTRL_PAGE_SIZE) {
653		iod->first_dma = dma_addr;
654		goto done;
655	}
656
657	nprps = DIV_ROUND_UP(length, NVME_CTRL_PAGE_SIZE);
658	if (nprps <= (256 / 8)) {
659		pool = dev->prp_small_pool;
660		iod->npages = 0;
661	} else {
662		pool = dev->prp_page_pool;
663		iod->npages = 1;
664	}
665
666	prp_list = dma_pool_alloc(pool, GFP_ATOMIC, &prp_dma);
667	if (!prp_list) {
668		iod->first_dma = dma_addr;
669		iod->npages = -1;
670		return BLK_STS_RESOURCE;
671	}
672	list[0] = prp_list;
673	iod->first_dma = prp_dma;
674	i = 0;
675	for (;;) {
676		if (i == NVME_CTRL_PAGE_SIZE >> 3) {
677			__le64 *old_prp_list = prp_list;
678			prp_list = dma_pool_alloc(pool, GFP_ATOMIC, &prp_dma);
679			if (!prp_list)
680				goto free_prps;
681			list[iod->npages++] = prp_list;
682			prp_list[0] = old_prp_list[i - 1];
683			old_prp_list[i - 1] = cpu_to_le64(prp_dma);
684			i = 1;
685		}
686		prp_list[i++] = cpu_to_le64(dma_addr);
687		dma_len -= NVME_CTRL_PAGE_SIZE;
688		dma_addr += NVME_CTRL_PAGE_SIZE;
689		length -= NVME_CTRL_PAGE_SIZE;
690		if (length <= 0)
691			break;
692		if (dma_len > 0)
693			continue;
694		if (unlikely(dma_len < 0))
695			goto bad_sgl;
696		sg = sg_next(sg);
697		dma_addr = sg_dma_address(sg);
698		dma_len = sg_dma_len(sg);
699	}
700done:
701	cmnd->dptr.prp1 = cpu_to_le64(sg_dma_address(iod->sg));
702	cmnd->dptr.prp2 = cpu_to_le64(iod->first_dma);
703	return BLK_STS_OK;
704free_prps:
705	nvme_free_prps(dev, req);
706	return BLK_STS_RESOURCE;
707bad_sgl:
708	WARN(DO_ONCE(nvme_print_sgl, iod->sg, iod->nents),
709			"Invalid SGL for payload:%d nents:%d\n",
710			blk_rq_payload_bytes(req), iod->nents);
711	return BLK_STS_IOERR;
712}
713
714static void nvme_pci_sgl_set_data(struct nvme_sgl_desc *sge,
715		struct scatterlist *sg)
716{
717	sge->addr = cpu_to_le64(sg_dma_address(sg));
718	sge->length = cpu_to_le32(sg_dma_len(sg));
719	sge->type = NVME_SGL_FMT_DATA_DESC << 4;
720}
721
722static void nvme_pci_sgl_set_seg(struct nvme_sgl_desc *sge,
723		dma_addr_t dma_addr, int entries)
724{
725	sge->addr = cpu_to_le64(dma_addr);
726	if (entries < SGES_PER_PAGE) {
727		sge->length = cpu_to_le32(entries * sizeof(*sge));
728		sge->type = NVME_SGL_FMT_LAST_SEG_DESC << 4;
729	} else {
730		sge->length = cpu_to_le32(NVME_CTRL_PAGE_SIZE);
731		sge->type = NVME_SGL_FMT_SEG_DESC << 4;
732	}
733}
734
735static blk_status_t nvme_pci_setup_sgls(struct nvme_dev *dev,
736		struct request *req, struct nvme_rw_command *cmd, int entries)
737{
738	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
739	struct dma_pool *pool;
740	struct nvme_sgl_desc *sg_list;
741	struct scatterlist *sg = iod->sg;
742	dma_addr_t sgl_dma;
743	int i = 0;
744
745	/* setting the transfer type as SGL */
746	cmd->flags = NVME_CMD_SGL_METABUF;
747
748	if (entries == 1) {
749		nvme_pci_sgl_set_data(&cmd->dptr.sgl, sg);
750		return BLK_STS_OK;
751	}
752
753	if (entries <= (256 / sizeof(struct nvme_sgl_desc))) {
754		pool = dev->prp_small_pool;
755		iod->npages = 0;
756	} else {
757		pool = dev->prp_page_pool;
758		iod->npages = 1;
759	}
760
761	sg_list = dma_pool_alloc(pool, GFP_ATOMIC, &sgl_dma);
762	if (!sg_list) {
763		iod->npages = -1;
764		return BLK_STS_RESOURCE;
765	}
766
767	nvme_pci_iod_list(req)[0] = sg_list;
768	iod->first_dma = sgl_dma;
769
770	nvme_pci_sgl_set_seg(&cmd->dptr.sgl, sgl_dma, entries);
771
772	do {
773		if (i == SGES_PER_PAGE) {
774			struct nvme_sgl_desc *old_sg_desc = sg_list;
775			struct nvme_sgl_desc *link = &old_sg_desc[i - 1];
776
777			sg_list = dma_pool_alloc(pool, GFP_ATOMIC, &sgl_dma);
778			if (!sg_list)
779				goto free_sgls;
780
781			i = 0;
782			nvme_pci_iod_list(req)[iod->npages++] = sg_list;
783			sg_list[i++] = *link;
784			nvme_pci_sgl_set_seg(link, sgl_dma, entries);
785		}
786
787		nvme_pci_sgl_set_data(&sg_list[i++], sg);
788		sg = sg_next(sg);
789	} while (--entries > 0);
790
791	return BLK_STS_OK;
792free_sgls:
793	nvme_free_sgls(dev, req);
794	return BLK_STS_RESOURCE;
795}
796
797static blk_status_t nvme_setup_prp_simple(struct nvme_dev *dev,
798		struct request *req, struct nvme_rw_command *cmnd,
799		struct bio_vec *bv)
800{
801	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
802	unsigned int offset = bv->bv_offset & (NVME_CTRL_PAGE_SIZE - 1);
803	unsigned int first_prp_len = NVME_CTRL_PAGE_SIZE - offset;
804
805	iod->first_dma = dma_map_bvec(dev->dev, bv, rq_dma_dir(req), 0);
806	if (dma_mapping_error(dev->dev, iod->first_dma))
807		return BLK_STS_RESOURCE;
808	iod->dma_len = bv->bv_len;
809
810	cmnd->dptr.prp1 = cpu_to_le64(iod->first_dma);
811	if (bv->bv_len > first_prp_len)
812		cmnd->dptr.prp2 = cpu_to_le64(iod->first_dma + first_prp_len);
813	else
814		cmnd->dptr.prp2 = 0;
815	return BLK_STS_OK;
816}
817
818static blk_status_t nvme_setup_sgl_simple(struct nvme_dev *dev,
819		struct request *req, struct nvme_rw_command *cmnd,
820		struct bio_vec *bv)
821{
822	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
823
824	iod->first_dma = dma_map_bvec(dev->dev, bv, rq_dma_dir(req), 0);
825	if (dma_mapping_error(dev->dev, iod->first_dma))
826		return BLK_STS_RESOURCE;
827	iod->dma_len = bv->bv_len;
828
829	cmnd->flags = NVME_CMD_SGL_METABUF;
830	cmnd->dptr.sgl.addr = cpu_to_le64(iod->first_dma);
831	cmnd->dptr.sgl.length = cpu_to_le32(iod->dma_len);
832	cmnd->dptr.sgl.type = NVME_SGL_FMT_DATA_DESC << 4;
833	return BLK_STS_OK;
834}
835
836static blk_status_t nvme_map_data(struct nvme_dev *dev, struct request *req,
837		struct nvme_command *cmnd)
838{
839	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
840	blk_status_t ret = BLK_STS_RESOURCE;
841	int nr_mapped;
842
843	if (blk_rq_nr_phys_segments(req) == 1) {
844		struct bio_vec bv = req_bvec(req);
845
846		if (!is_pci_p2pdma_page(bv.bv_page)) {
847			if (bv.bv_offset + bv.bv_len <= NVME_CTRL_PAGE_SIZE * 2)
848				return nvme_setup_prp_simple(dev, req,
849							     &cmnd->rw, &bv);
850
851			if (iod->nvmeq->qid && sgl_threshold &&
852			    dev->ctrl.sgls & ((1 << 0) | (1 << 1)))
853				return nvme_setup_sgl_simple(dev, req,
854							     &cmnd->rw, &bv);
855		}
856	}
857
858	iod->dma_len = 0;
859	iod->sg = mempool_alloc(dev->iod_mempool, GFP_ATOMIC);
860	if (!iod->sg)
861		return BLK_STS_RESOURCE;
862	sg_init_table(iod->sg, blk_rq_nr_phys_segments(req));
863	iod->nents = blk_rq_map_sg(req->q, req, iod->sg);
864	if (!iod->nents)
865		goto out_free_sg;
866
867	if (is_pci_p2pdma_page(sg_page(iod->sg)))
868		nr_mapped = pci_p2pdma_map_sg_attrs(dev->dev, iod->sg,
869				iod->nents, rq_dma_dir(req), DMA_ATTR_NO_WARN);
870	else
871		nr_mapped = dma_map_sg_attrs(dev->dev, iod->sg, iod->nents,
872					     rq_dma_dir(req), DMA_ATTR_NO_WARN);
873	if (!nr_mapped)
874		goto out_free_sg;
875
876	iod->use_sgl = nvme_pci_use_sgls(dev, req);
877	if (iod->use_sgl)
878		ret = nvme_pci_setup_sgls(dev, req, &cmnd->rw, nr_mapped);
879	else
880		ret = nvme_pci_setup_prps(dev, req, &cmnd->rw);
881	if (ret != BLK_STS_OK)
882		goto out_unmap_sg;
883	return BLK_STS_OK;
884
885out_unmap_sg:
886	nvme_unmap_sg(dev, req);
887out_free_sg:
888	mempool_free(iod->sg, dev->iod_mempool);
889	return ret;
890}
891
892static blk_status_t nvme_map_metadata(struct nvme_dev *dev, struct request *req,
893		struct nvme_command *cmnd)
894{
895	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
896
897	iod->meta_dma = dma_map_bvec(dev->dev, rq_integrity_vec(req),
898			rq_dma_dir(req), 0);
899	if (dma_mapping_error(dev->dev, iod->meta_dma))
900		return BLK_STS_IOERR;
901	cmnd->rw.metadata = cpu_to_le64(iod->meta_dma);
902	return BLK_STS_OK;
903}
904
905/*
906 * NOTE: ns is NULL when called on the admin queue.
907 */
908static blk_status_t nvme_queue_rq(struct blk_mq_hw_ctx *hctx,
909			 const struct blk_mq_queue_data *bd)
910{
911	struct nvme_ns *ns = hctx->queue->queuedata;
912	struct nvme_queue *nvmeq = hctx->driver_data;
913	struct nvme_dev *dev = nvmeq->dev;
914	struct request *req = bd->rq;
915	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
916	struct nvme_command *cmnd = &iod->cmd;
917	blk_status_t ret;
918
919	iod->aborted = 0;
920	iod->npages = -1;
921	iod->nents = 0;
922
923	/*
924	 * We should not need to do this, but we're still using this to
925	 * ensure we can drain requests on a dying queue.
926	 */
927	if (unlikely(!test_bit(NVMEQ_ENABLED, &nvmeq->flags)))
928		return BLK_STS_IOERR;
929
930	ret = nvme_setup_cmd(ns, req, cmnd);
931	if (ret)
932		return ret;
933
934	if (blk_rq_nr_phys_segments(req)) {
935		ret = nvme_map_data(dev, req, cmnd);
936		if (ret)
937			goto out_free_cmd;
938	}
939
940	if (blk_integrity_rq(req)) {
941		ret = nvme_map_metadata(dev, req, cmnd);
942		if (ret)
943			goto out_unmap_data;
944	}
945
946	blk_mq_start_request(req);
947	nvme_submit_cmd(nvmeq, cmnd, bd->last);
948	return BLK_STS_OK;
949out_unmap_data:
950	if (blk_rq_nr_phys_segments(req))
951		nvme_unmap_data(dev, req);
952out_free_cmd:
953	nvme_cleanup_cmd(req);
954	return ret;
955}
956
957static void nvme_pci_complete_rq(struct request *req)
958{
959	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
960	struct nvme_dev *dev = iod->nvmeq->dev;
961
962	if (blk_integrity_rq(req))
963		dma_unmap_page(dev->dev, iod->meta_dma,
964			       rq_integrity_vec(req)->bv_len, rq_dma_dir(req));
965
966	if (blk_rq_nr_phys_segments(req))
967		nvme_unmap_data(dev, req);
968	nvme_complete_rq(req);
969}
970
971/* We read the CQE phase first to check if the rest of the entry is valid */
972static inline bool nvme_cqe_pending(struct nvme_queue *nvmeq)
973{
974	struct nvme_completion *hcqe = &nvmeq->cqes[nvmeq->cq_head];
975
976	return (le16_to_cpu(READ_ONCE(hcqe->status)) & 1) == nvmeq->cq_phase;
977}
978
979static inline void nvme_ring_cq_doorbell(struct nvme_queue *nvmeq)
980{
981	u16 head = nvmeq->cq_head;
982
983	if (nvme_dbbuf_update_and_check_event(head, nvmeq->dbbuf_cq_db,
984					      nvmeq->dbbuf_cq_ei))
985		writel(head, nvmeq->q_db + nvmeq->dev->db_stride);
986}
987
988static inline struct blk_mq_tags *nvme_queue_tagset(struct nvme_queue *nvmeq)
989{
990	if (!nvmeq->qid)
991		return nvmeq->dev->admin_tagset.tags[0];
992	return nvmeq->dev->tagset.tags[nvmeq->qid - 1];
993}
994
995static inline void nvme_handle_cqe(struct nvme_queue *nvmeq, u16 idx)
996{
997	struct nvme_completion *cqe = &nvmeq->cqes[idx];
998	__u16 command_id = READ_ONCE(cqe->command_id);
999	struct request *req;
1000
1001	/*
1002	 * AEN requests are special as they don't time out and can
1003	 * survive any kind of queue freeze and often don't respond to
1004	 * aborts.  We don't even bother to allocate a struct request
1005	 * for them but rather special case them here.
1006	 */
1007	if (unlikely(nvme_is_aen_req(nvmeq->qid, command_id))) {
1008		nvme_complete_async_event(&nvmeq->dev->ctrl,
1009				cqe->status, &cqe->result);
1010		return;
1011	}
1012
1013	req = nvme_find_rq(nvme_queue_tagset(nvmeq), command_id);
1014	if (unlikely(!req)) {
1015		dev_warn(nvmeq->dev->ctrl.device,
1016			"invalid id %d completed on queue %d\n",
1017			command_id, le16_to_cpu(cqe->sq_id));
1018		return;
1019	}
1020
1021	trace_nvme_sq(req, cqe->sq_head, nvmeq->sq_tail);
1022	if (!nvme_try_complete_req(req, cqe->status, cqe->result))
1023		nvme_pci_complete_rq(req);
1024}
1025
1026static inline void nvme_update_cq_head(struct nvme_queue *nvmeq)
1027{
1028	u32 tmp = nvmeq->cq_head + 1;
1029
1030	if (tmp == nvmeq->q_depth) {
1031		nvmeq->cq_head = 0;
1032		nvmeq->cq_phase ^= 1;
1033	} else {
1034		nvmeq->cq_head = tmp;
1035	}
1036}
1037
1038static inline int nvme_process_cq(struct nvme_queue *nvmeq)
1039{
1040	int found = 0;
1041
1042	while (nvme_cqe_pending(nvmeq)) {
1043		found++;
1044		/*
1045		 * load-load control dependency between phase and the rest of
1046		 * the cqe requires a full read memory barrier
1047		 */
1048		dma_rmb();
1049		nvme_handle_cqe(nvmeq, nvmeq->cq_head);
1050		nvme_update_cq_head(nvmeq);
1051	}
1052
1053	if (found)
1054		nvme_ring_cq_doorbell(nvmeq);
1055	return found;
1056}
1057
1058static irqreturn_t nvme_irq(int irq, void *data)
1059{
1060	struct nvme_queue *nvmeq = data;
1061	irqreturn_t ret = IRQ_NONE;
1062
1063	/*
1064	 * The rmb/wmb pair ensures we see all updates from a previous run of
1065	 * the irq handler, even if that was on another CPU.
1066	 */
1067	rmb();
1068	if (nvme_process_cq(nvmeq))
1069		ret = IRQ_HANDLED;
1070	wmb();
1071
1072	return ret;
1073}
1074
1075static irqreturn_t nvme_irq_check(int irq, void *data)
1076{
1077	struct nvme_queue *nvmeq = data;
1078
1079	if (nvme_cqe_pending(nvmeq))
1080		return IRQ_WAKE_THREAD;
1081	return IRQ_NONE;
1082}
1083
1084/*
1085 * Poll for completions for any interrupt driven queue
1086 * Can be called from any context.
1087 */
1088static void nvme_poll_irqdisable(struct nvme_queue *nvmeq)
1089{
1090	struct pci_dev *pdev = to_pci_dev(nvmeq->dev->dev);
1091
1092	WARN_ON_ONCE(test_bit(NVMEQ_POLLED, &nvmeq->flags));
1093
1094	disable_irq(pci_irq_vector(pdev, nvmeq->cq_vector));
1095	nvme_process_cq(nvmeq);
1096	enable_irq(pci_irq_vector(pdev, nvmeq->cq_vector));
1097}
1098
1099static int nvme_poll(struct blk_mq_hw_ctx *hctx)
1100{
1101	struct nvme_queue *nvmeq = hctx->driver_data;
1102	bool found;
1103
1104	if (!nvme_cqe_pending(nvmeq))
1105		return 0;
1106
1107	spin_lock(&nvmeq->cq_poll_lock);
1108	found = nvme_process_cq(nvmeq);
1109	spin_unlock(&nvmeq->cq_poll_lock);
1110
1111	return found;
1112}
1113
1114static void nvme_pci_submit_async_event(struct nvme_ctrl *ctrl)
1115{
1116	struct nvme_dev *dev = to_nvme_dev(ctrl);
1117	struct nvme_queue *nvmeq = &dev->queues[0];
1118	struct nvme_command c;
1119
1120	memset(&c, 0, sizeof(c));
1121	c.common.opcode = nvme_admin_async_event;
1122	c.common.command_id = NVME_AQ_BLK_MQ_DEPTH;
1123	nvme_submit_cmd(nvmeq, &c, true);
1124}
1125
1126static int adapter_delete_queue(struct nvme_dev *dev, u8 opcode, u16 id)
1127{
1128	struct nvme_command c;
1129
1130	memset(&c, 0, sizeof(c));
1131	c.delete_queue.opcode = opcode;
1132	c.delete_queue.qid = cpu_to_le16(id);
1133
1134	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1135}
1136
1137static int adapter_alloc_cq(struct nvme_dev *dev, u16 qid,
1138		struct nvme_queue *nvmeq, s16 vector)
1139{
1140	struct nvme_command c;
1141	int flags = NVME_QUEUE_PHYS_CONTIG;
1142
1143	if (!test_bit(NVMEQ_POLLED, &nvmeq->flags))
1144		flags |= NVME_CQ_IRQ_ENABLED;
1145
1146	/*
1147	 * Note: we (ab)use the fact that the prp fields survive if no data
1148	 * is attached to the request.
1149	 */
1150	memset(&c, 0, sizeof(c));
1151	c.create_cq.opcode = nvme_admin_create_cq;
1152	c.create_cq.prp1 = cpu_to_le64(nvmeq->cq_dma_addr);
1153	c.create_cq.cqid = cpu_to_le16(qid);
1154	c.create_cq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
1155	c.create_cq.cq_flags = cpu_to_le16(flags);
1156	c.create_cq.irq_vector = cpu_to_le16(vector);
1157
1158	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1159}
1160
1161static int adapter_alloc_sq(struct nvme_dev *dev, u16 qid,
1162						struct nvme_queue *nvmeq)
1163{
1164	struct nvme_ctrl *ctrl = &dev->ctrl;
1165	struct nvme_command c;
1166	int flags = NVME_QUEUE_PHYS_CONTIG;
1167
1168	/*
1169	 * Some drives have a bug that auto-enables WRRU if MEDIUM isn't
1170	 * set. Since URGENT priority is zeroes, it makes all queues
1171	 * URGENT.
1172	 */
1173	if (ctrl->quirks & NVME_QUIRK_MEDIUM_PRIO_SQ)
1174		flags |= NVME_SQ_PRIO_MEDIUM;
1175
1176	/*
1177	 * Note: we (ab)use the fact that the prp fields survive if no data
1178	 * is attached to the request.
1179	 */
1180	memset(&c, 0, sizeof(c));
1181	c.create_sq.opcode = nvme_admin_create_sq;
1182	c.create_sq.prp1 = cpu_to_le64(nvmeq->sq_dma_addr);
1183	c.create_sq.sqid = cpu_to_le16(qid);
1184	c.create_sq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
1185	c.create_sq.sq_flags = cpu_to_le16(flags);
1186	c.create_sq.cqid = cpu_to_le16(qid);
1187
1188	return nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1189}
1190
1191static int adapter_delete_cq(struct nvme_dev *dev, u16 cqid)
1192{
1193	return adapter_delete_queue(dev, nvme_admin_delete_cq, cqid);
1194}
1195
1196static int adapter_delete_sq(struct nvme_dev *dev, u16 sqid)
1197{
1198	return adapter_delete_queue(dev, nvme_admin_delete_sq, sqid);
1199}
1200
1201static void abort_endio(struct request *req, blk_status_t error)
1202{
1203	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
1204	struct nvme_queue *nvmeq = iod->nvmeq;
1205
1206	dev_warn(nvmeq->dev->ctrl.device,
1207		 "Abort status: 0x%x", nvme_req(req)->status);
1208	atomic_inc(&nvmeq->dev->ctrl.abort_limit);
1209	blk_mq_free_request(req);
1210}
1211
1212static bool nvme_should_reset(struct nvme_dev *dev, u32 csts)
1213{
1214	/* If true, indicates loss of adapter communication, possibly by a
1215	 * NVMe Subsystem reset.
1216	 */
1217	bool nssro = dev->subsystem && (csts & NVME_CSTS_NSSRO);
1218
1219	/* If there is a reset/reinit ongoing, we shouldn't reset again. */
1220	switch (dev->ctrl.state) {
1221	case NVME_CTRL_RESETTING:
1222	case NVME_CTRL_CONNECTING:
1223		return false;
1224	default:
1225		break;
1226	}
1227
1228	/* We shouldn't reset unless the controller is on fatal error state
1229	 * _or_ if we lost the communication with it.
1230	 */
1231	if (!(csts & NVME_CSTS_CFS) && !nssro)
1232		return false;
1233
1234	return true;
1235}
1236
1237static void nvme_warn_reset(struct nvme_dev *dev, u32 csts)
1238{
1239	/* Read a config register to help see what died. */
1240	u16 pci_status;
1241	int result;
1242
1243	result = pci_read_config_word(to_pci_dev(dev->dev), PCI_STATUS,
1244				      &pci_status);
1245	if (result == PCIBIOS_SUCCESSFUL)
1246		dev_warn(dev->ctrl.device,
1247			 "controller is down; will reset: CSTS=0x%x, PCI_STATUS=0x%hx\n",
1248			 csts, pci_status);
1249	else
1250		dev_warn(dev->ctrl.device,
1251			 "controller is down; will reset: CSTS=0x%x, PCI_STATUS read failed (%d)\n",
1252			 csts, result);
1253}
1254
1255static enum blk_eh_timer_return nvme_timeout(struct request *req, bool reserved)
1256{
1257	struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
1258	struct nvme_queue *nvmeq = iod->nvmeq;
1259	struct nvme_dev *dev = nvmeq->dev;
1260	struct request *abort_req;
1261	struct nvme_command cmd;
1262	u32 csts = readl(dev->bar + NVME_REG_CSTS);
1263
1264	/* If PCI error recovery process is happening, we cannot reset or
1265	 * the recovery mechanism will surely fail.
1266	 */
1267	mb();
1268	if (pci_channel_offline(to_pci_dev(dev->dev)))
1269		return BLK_EH_RESET_TIMER;
1270
1271	/*
1272	 * Reset immediately if the controller is failed
1273	 */
1274	if (nvme_should_reset(dev, csts)) {
1275		nvme_warn_reset(dev, csts);
1276		nvme_dev_disable(dev, false);
1277		nvme_reset_ctrl(&dev->ctrl);
1278		return BLK_EH_DONE;
1279	}
1280
1281	/*
1282	 * Did we miss an interrupt?
1283	 */
1284	if (test_bit(NVMEQ_POLLED, &nvmeq->flags))
1285		nvme_poll(req->mq_hctx);
1286	else
1287		nvme_poll_irqdisable(nvmeq);
1288
1289	if (blk_mq_rq_state(req) != MQ_RQ_IN_FLIGHT) {
1290		dev_warn(dev->ctrl.device,
1291			 "I/O %d QID %d timeout, completion polled\n",
1292			 req->tag, nvmeq->qid);
1293		return BLK_EH_DONE;
1294	}
1295
1296	/*
1297	 * Shutdown immediately if controller times out while starting. The
1298	 * reset work will see the pci device disabled when it gets the forced
1299	 * cancellation error. All outstanding requests are completed on
1300	 * shutdown, so we return BLK_EH_DONE.
1301	 */
1302	switch (dev->ctrl.state) {
1303	case NVME_CTRL_CONNECTING:
1304		nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DELETING);
1305		fallthrough;
1306	case NVME_CTRL_DELETING:
1307		dev_warn_ratelimited(dev->ctrl.device,
1308			 "I/O %d QID %d timeout, disable controller\n",
1309			 req->tag, nvmeq->qid);
1310		nvme_req(req)->flags |= NVME_REQ_CANCELLED;
1311		nvme_dev_disable(dev, true);
1312		return BLK_EH_DONE;
1313	case NVME_CTRL_RESETTING:
1314		return BLK_EH_RESET_TIMER;
1315	default:
1316		break;
1317	}
1318
1319	/*
1320	 * Shutdown the controller immediately and schedule a reset if the
1321	 * command was already aborted once before and still hasn't been
1322	 * returned to the driver, or if this is the admin queue.
1323	 */
1324	if (!nvmeq->qid || iod->aborted) {
1325		dev_warn(dev->ctrl.device,
1326			 "I/O %d QID %d timeout, reset controller\n",
1327			 req->tag, nvmeq->qid);
1328		nvme_req(req)->flags |= NVME_REQ_CANCELLED;
1329		nvme_dev_disable(dev, false);
1330		nvme_reset_ctrl(&dev->ctrl);
1331
1332		return BLK_EH_DONE;
1333	}
1334
1335	if (atomic_dec_return(&dev->ctrl.abort_limit) < 0) {
1336		atomic_inc(&dev->ctrl.abort_limit);
1337		return BLK_EH_RESET_TIMER;
1338	}
1339	iod->aborted = 1;
1340
1341	memset(&cmd, 0, sizeof(cmd));
1342	cmd.abort.opcode = nvme_admin_abort_cmd;
1343	cmd.abort.cid = nvme_cid(req);
1344	cmd.abort.sqid = cpu_to_le16(nvmeq->qid);
1345
1346	dev_warn(nvmeq->dev->ctrl.device,
1347		"I/O %d QID %d timeout, aborting\n",
1348		 req->tag, nvmeq->qid);
1349
1350	abort_req = nvme_alloc_request(dev->ctrl.admin_q, &cmd,
1351			BLK_MQ_REQ_NOWAIT);
1352	if (IS_ERR(abort_req)) {
1353		atomic_inc(&dev->ctrl.abort_limit);
1354		return BLK_EH_RESET_TIMER;
1355	}
1356
1357	abort_req->end_io_data = NULL;
1358	blk_execute_rq_nowait(abort_req->q, NULL, abort_req, 0, abort_endio);
1359
1360	/*
1361	 * The aborted req will be completed on receiving the abort req.
1362	 * We enable the timer again. If hit twice, it'll cause a device reset,
1363	 * as the device then is in a faulty state.
1364	 */
1365	return BLK_EH_RESET_TIMER;
1366}
1367
1368static void nvme_free_queue(struct nvme_queue *nvmeq)
1369{
1370	dma_free_coherent(nvmeq->dev->dev, CQ_SIZE(nvmeq),
1371				(void *)nvmeq->cqes, nvmeq->cq_dma_addr);
1372	if (!nvmeq->sq_cmds)
1373		return;
1374
1375	if (test_and_clear_bit(NVMEQ_SQ_CMB, &nvmeq->flags)) {
1376		pci_free_p2pmem(to_pci_dev(nvmeq->dev->dev),
1377				nvmeq->sq_cmds, SQ_SIZE(nvmeq));
1378	} else {
1379		dma_free_coherent(nvmeq->dev->dev, SQ_SIZE(nvmeq),
1380				nvmeq->sq_cmds, nvmeq->sq_dma_addr);
1381	}
1382}
1383
1384static void nvme_free_queues(struct nvme_dev *dev, int lowest)
1385{
1386	int i;
1387
1388	for (i = dev->ctrl.queue_count - 1; i >= lowest; i--) {
1389		dev->ctrl.queue_count--;
1390		nvme_free_queue(&dev->queues[i]);
1391	}
1392}
1393
1394/**
1395 * nvme_suspend_queue - put queue into suspended state
1396 * @nvmeq: queue to suspend
1397 */
1398static int nvme_suspend_queue(struct nvme_queue *nvmeq)
1399{
1400	if (!test_and_clear_bit(NVMEQ_ENABLED, &nvmeq->flags))
1401		return 1;
1402
1403	/* ensure that nvme_queue_rq() sees NVMEQ_ENABLED cleared */
1404	mb();
1405
1406	nvmeq->dev->online_queues--;
1407	if (!nvmeq->qid && nvmeq->dev->ctrl.admin_q)
1408		nvme_stop_admin_queue(&nvmeq->dev->ctrl);
1409	if (!test_and_clear_bit(NVMEQ_POLLED, &nvmeq->flags))
1410		pci_free_irq(to_pci_dev(nvmeq->dev->dev), nvmeq->cq_vector, nvmeq);
1411	return 0;
1412}
1413
1414static void nvme_suspend_io_queues(struct nvme_dev *dev)
1415{
1416	int i;
1417
1418	for (i = dev->ctrl.queue_count - 1; i > 0; i--)
1419		nvme_suspend_queue(&dev->queues[i]);
1420}
1421
1422static void nvme_disable_admin_queue(struct nvme_dev *dev, bool shutdown)
1423{
1424	struct nvme_queue *nvmeq = &dev->queues[0];
1425
1426	if (shutdown)
1427		nvme_shutdown_ctrl(&dev->ctrl);
1428	else
1429		nvme_disable_ctrl(&dev->ctrl);
1430
1431	nvme_poll_irqdisable(nvmeq);
1432}
1433
1434/*
1435 * Called only on a device that has been disabled and after all other threads
1436 * that can check this device's completion queues have synced, except
1437 * nvme_poll(). This is the last chance for the driver to see a natural
1438 * completion before nvme_cancel_request() terminates all incomplete requests.
1439 */
1440static void nvme_reap_pending_cqes(struct nvme_dev *dev)
1441{
1442	int i;
1443
1444	for (i = dev->ctrl.queue_count - 1; i > 0; i--) {
1445		spin_lock(&dev->queues[i].cq_poll_lock);
1446		nvme_process_cq(&dev->queues[i]);
1447		spin_unlock(&dev->queues[i].cq_poll_lock);
1448	}
1449}
1450
1451static int nvme_cmb_qdepth(struct nvme_dev *dev, int nr_io_queues,
1452				int entry_size)
1453{
1454	int q_depth = dev->q_depth;
1455	unsigned q_size_aligned = roundup(q_depth * entry_size,
1456					  NVME_CTRL_PAGE_SIZE);
1457
1458	if (q_size_aligned * nr_io_queues > dev->cmb_size) {
1459		u64 mem_per_q = div_u64(dev->cmb_size, nr_io_queues);
1460
1461		mem_per_q = round_down(mem_per_q, NVME_CTRL_PAGE_SIZE);
1462		q_depth = div_u64(mem_per_q, entry_size);
1463
1464		/*
1465		 * Ensure the reduced q_depth is above some threshold where it
1466		 * would be better to map queues in system memory with the
1467		 * original depth
1468		 */
1469		if (q_depth < 64)
1470			return -ENOMEM;
1471	}
1472
1473	return q_depth;
1474}
1475
1476static int nvme_alloc_sq_cmds(struct nvme_dev *dev, struct nvme_queue *nvmeq,
1477				int qid)
1478{
1479	struct pci_dev *pdev = to_pci_dev(dev->dev);
1480
1481	if (qid && dev->cmb_use_sqes && (dev->cmbsz & NVME_CMBSZ_SQS)) {
1482		nvmeq->sq_cmds = pci_alloc_p2pmem(pdev, SQ_SIZE(nvmeq));
1483		if (nvmeq->sq_cmds) {
1484			nvmeq->sq_dma_addr = pci_p2pmem_virt_to_bus(pdev,
1485							nvmeq->sq_cmds);
1486			if (nvmeq->sq_dma_addr) {
1487				set_bit(NVMEQ_SQ_CMB, &nvmeq->flags);
1488				return 0;
1489			}
1490
1491			pci_free_p2pmem(pdev, nvmeq->sq_cmds, SQ_SIZE(nvmeq));
1492		}
1493	}
1494
1495	nvmeq->sq_cmds = dma_alloc_coherent(dev->dev, SQ_SIZE(nvmeq),
1496				&nvmeq->sq_dma_addr, GFP_KERNEL);
1497	if (!nvmeq->sq_cmds)
1498		return -ENOMEM;
1499	return 0;
1500}
1501
1502static int nvme_alloc_queue(struct nvme_dev *dev, int qid, int depth)
1503{
1504	struct nvme_queue *nvmeq = &dev->queues[qid];
1505
1506	if (dev->ctrl.queue_count > qid)
1507		return 0;
1508
1509	nvmeq->sqes = qid ? dev->io_sqes : NVME_ADM_SQES;
1510	nvmeq->q_depth = depth;
1511	nvmeq->cqes = dma_alloc_coherent(dev->dev, CQ_SIZE(nvmeq),
1512					 &nvmeq->cq_dma_addr, GFP_KERNEL);
1513	if (!nvmeq->cqes)
1514		goto free_nvmeq;
1515
1516	if (nvme_alloc_sq_cmds(dev, nvmeq, qid))
1517		goto free_cqdma;
1518
1519	nvmeq->dev = dev;
1520	spin_lock_init(&nvmeq->sq_lock);
1521	spin_lock_init(&nvmeq->cq_poll_lock);
1522	nvmeq->cq_head = 0;
1523	nvmeq->cq_phase = 1;
1524	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
1525	nvmeq->qid = qid;
1526	dev->ctrl.queue_count++;
1527
1528	return 0;
1529
1530 free_cqdma:
1531	dma_free_coherent(dev->dev, CQ_SIZE(nvmeq), (void *)nvmeq->cqes,
1532			  nvmeq->cq_dma_addr);
1533 free_nvmeq:
1534	return -ENOMEM;
1535}
1536
1537static int queue_request_irq(struct nvme_queue *nvmeq)
1538{
1539	struct pci_dev *pdev = to_pci_dev(nvmeq->dev->dev);
1540	int nr = nvmeq->dev->ctrl.instance;
1541
1542	if (use_threaded_interrupts) {
1543		return pci_request_irq(pdev, nvmeq->cq_vector, nvme_irq_check,
1544				nvme_irq, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
1545	} else {
1546		return pci_request_irq(pdev, nvmeq->cq_vector, nvme_irq,
1547				NULL, nvmeq, "nvme%dq%d", nr, nvmeq->qid);
1548	}
1549}
1550
1551static void nvme_init_queue(struct nvme_queue *nvmeq, u16 qid)
1552{
1553	struct nvme_dev *dev = nvmeq->dev;
1554
1555	nvmeq->sq_tail = 0;
1556	nvmeq->last_sq_tail = 0;
1557	nvmeq->cq_head = 0;
1558	nvmeq->cq_phase = 1;
1559	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
1560	memset((void *)nvmeq->cqes, 0, CQ_SIZE(nvmeq));
1561	nvme_dbbuf_init(dev, nvmeq, qid);
1562	dev->online_queues++;
1563	wmb(); /* ensure the first interrupt sees the initialization */
1564}
1565
1566static int nvme_create_queue(struct nvme_queue *nvmeq, int qid, bool polled)
1567{
1568	struct nvme_dev *dev = nvmeq->dev;
1569	int result;
1570	u16 vector = 0;
1571
1572	clear_bit(NVMEQ_DELETE_ERROR, &nvmeq->flags);
1573
1574	/*
1575	 * A queue's vector matches the queue identifier unless the controller
1576	 * has only one vector available.
1577	 */
1578	if (!polled)
1579		vector = dev->num_vecs == 1 ? 0 : qid;
1580	else
1581		set_bit(NVMEQ_POLLED, &nvmeq->flags);
1582
1583	result = adapter_alloc_cq(dev, qid, nvmeq, vector);
1584	if (result)
1585		return result;
1586
1587	result = adapter_alloc_sq(dev, qid, nvmeq);
1588	if (result < 0)
1589		return result;
1590	if (result)
1591		goto release_cq;
1592
1593	nvmeq->cq_vector = vector;
1594	nvme_init_queue(nvmeq, qid);
1595
1596	if (!polled) {
1597		result = queue_request_irq(nvmeq);
1598		if (result < 0)
1599			goto release_sq;
1600	}
1601
1602	set_bit(NVMEQ_ENABLED, &nvmeq->flags);
1603	return result;
1604
1605release_sq:
1606	dev->online_queues--;
1607	adapter_delete_sq(dev, qid);
1608release_cq:
1609	adapter_delete_cq(dev, qid);
1610	return result;
1611}
1612
1613static const struct blk_mq_ops nvme_mq_admin_ops = {
1614	.queue_rq	= nvme_queue_rq,
1615	.complete	= nvme_pci_complete_rq,
1616	.init_hctx	= nvme_admin_init_hctx,
1617	.init_request	= nvme_init_request,
1618	.timeout	= nvme_timeout,
1619};
1620
1621static const struct blk_mq_ops nvme_mq_ops = {
1622	.queue_rq	= nvme_queue_rq,
1623	.complete	= nvme_pci_complete_rq,
1624	.commit_rqs	= nvme_commit_rqs,
1625	.init_hctx	= nvme_init_hctx,
1626	.init_request	= nvme_init_request,
1627	.map_queues	= nvme_pci_map_queues,
1628	.timeout	= nvme_timeout,
1629	.poll		= nvme_poll,
1630};
1631
1632static void nvme_dev_remove_admin(struct nvme_dev *dev)
1633{
1634	if (dev->ctrl.admin_q && !blk_queue_dying(dev->ctrl.admin_q)) {
1635		/*
1636		 * If the controller was reset during removal, it's possible
1637		 * user requests may be waiting on a stopped queue. Start the
1638		 * queue to flush these to completion.
1639		 */
1640		nvme_start_admin_queue(&dev->ctrl);
1641		blk_cleanup_queue(dev->ctrl.admin_q);
1642		blk_mq_free_tag_set(&dev->admin_tagset);
1643	}
1644}
1645
1646static int nvme_alloc_admin_tags(struct nvme_dev *dev)
1647{
1648	if (!dev->ctrl.admin_q) {
1649		dev->admin_tagset.ops = &nvme_mq_admin_ops;
1650		dev->admin_tagset.nr_hw_queues = 1;
1651
1652		dev->admin_tagset.queue_depth = NVME_AQ_MQ_TAG_DEPTH;
1653		dev->admin_tagset.timeout = ADMIN_TIMEOUT;
1654		dev->admin_tagset.numa_node = dev->ctrl.numa_node;
1655		dev->admin_tagset.cmd_size = sizeof(struct nvme_iod);
1656		dev->admin_tagset.flags = BLK_MQ_F_NO_SCHED;
1657		dev->admin_tagset.driver_data = dev;
1658
1659		if (blk_mq_alloc_tag_set(&dev->admin_tagset))
1660			return -ENOMEM;
1661		dev->ctrl.admin_tagset = &dev->admin_tagset;
1662
1663		dev->ctrl.admin_q = blk_mq_init_queue(&dev->admin_tagset);
1664		if (IS_ERR(dev->ctrl.admin_q)) {
1665			blk_mq_free_tag_set(&dev->admin_tagset);
1666			dev->ctrl.admin_q = NULL;
1667			return -ENOMEM;
1668		}
1669		if (!blk_get_queue(dev->ctrl.admin_q)) {
1670			nvme_dev_remove_admin(dev);
1671			dev->ctrl.admin_q = NULL;
1672			return -ENODEV;
1673		}
1674	} else
1675		nvme_start_admin_queue(&dev->ctrl);
1676
1677	return 0;
1678}
1679
1680static unsigned long db_bar_size(struct nvme_dev *dev, unsigned nr_io_queues)
1681{
1682	return NVME_REG_DBS + ((nr_io_queues + 1) * 8 * dev->db_stride);
1683}
1684
1685static int nvme_remap_bar(struct nvme_dev *dev, unsigned long size)
1686{
1687	struct pci_dev *pdev = to_pci_dev(dev->dev);
1688
1689	if (size <= dev->bar_mapped_size)
1690		return 0;
1691	if (size > pci_resource_len(pdev, 0))
1692		return -ENOMEM;
1693	if (dev->bar)
1694		iounmap(dev->bar);
1695	dev->bar = ioremap(pci_resource_start(pdev, 0), size);
1696	if (!dev->bar) {
1697		dev->bar_mapped_size = 0;
1698		return -ENOMEM;
1699	}
1700	dev->bar_mapped_size = size;
1701	dev->dbs = dev->bar + NVME_REG_DBS;
1702
1703	return 0;
1704}
1705
1706static int nvme_pci_configure_admin_queue(struct nvme_dev *dev)
1707{
1708	int result;
1709	u32 aqa;
1710	struct nvme_queue *nvmeq;
1711
1712	result = nvme_remap_bar(dev, db_bar_size(dev, 0));
1713	if (result < 0)
1714		return result;
1715
1716	dev->subsystem = readl(dev->bar + NVME_REG_VS) >= NVME_VS(1, 1, 0) ?
1717				NVME_CAP_NSSRC(dev->ctrl.cap) : 0;
1718
1719	if (dev->subsystem &&
1720	    (readl(dev->bar + NVME_REG_CSTS) & NVME_CSTS_NSSRO))
1721		writel(NVME_CSTS_NSSRO, dev->bar + NVME_REG_CSTS);
1722
1723	result = nvme_disable_ctrl(&dev->ctrl);
1724	if (result < 0)
1725		return result;
1726
1727	result = nvme_alloc_queue(dev, 0, NVME_AQ_DEPTH);
1728	if (result)
1729		return result;
1730
1731	dev->ctrl.numa_node = dev_to_node(dev->dev);
1732
1733	nvmeq = &dev->queues[0];
1734	aqa = nvmeq->q_depth - 1;
1735	aqa |= aqa << 16;
1736
1737	writel(aqa, dev->bar + NVME_REG_AQA);
1738	lo_hi_writeq(nvmeq->sq_dma_addr, dev->bar + NVME_REG_ASQ);
1739	lo_hi_writeq(nvmeq->cq_dma_addr, dev->bar + NVME_REG_ACQ);
1740
1741	result = nvme_enable_ctrl(&dev->ctrl);
1742	if (result)
1743		return result;
1744
1745	nvmeq->cq_vector = 0;
1746	nvme_init_queue(nvmeq, 0);
1747	result = queue_request_irq(nvmeq);
1748	if (result) {
1749		dev->online_queues--;
1750		return result;
1751	}
1752
1753	set_bit(NVMEQ_ENABLED, &nvmeq->flags);
1754	return result;
1755}
1756
1757static int nvme_create_io_queues(struct nvme_dev *dev)
1758{
1759	unsigned i, max, rw_queues;
1760	int ret = 0;
1761
1762	for (i = dev->ctrl.queue_count; i <= dev->max_qid; i++) {
1763		if (nvme_alloc_queue(dev, i, dev->q_depth)) {
1764			ret = -ENOMEM;
1765			break;
1766		}
1767	}
1768
1769	max = min(dev->max_qid, dev->ctrl.queue_count - 1);
1770	if (max != 1 && dev->io_queues[HCTX_TYPE_POLL]) {
1771		rw_queues = dev->io_queues[HCTX_TYPE_DEFAULT] +
1772				dev->io_queues[HCTX_TYPE_READ];
1773	} else {
1774		rw_queues = max;
1775	}
1776
1777	for (i = dev->online_queues; i <= max; i++) {
1778		bool polled = i > rw_queues;
1779
1780		ret = nvme_create_queue(&dev->queues[i], i, polled);
1781		if (ret)
1782			break;
1783	}
1784
1785	/*
1786	 * Ignore failing Create SQ/CQ commands, we can continue with less
1787	 * than the desired amount of queues, and even a controller without
1788	 * I/O queues can still be used to issue admin commands.  This might
1789	 * be useful to upgrade a buggy firmware for example.
1790	 */
1791	return ret >= 0 ? 0 : ret;
1792}
1793
1794static ssize_t nvme_cmb_show(struct device *dev,
1795			     struct device_attribute *attr,
1796			     char *buf)
1797{
1798	struct nvme_dev *ndev = to_nvme_dev(dev_get_drvdata(dev));
1799
1800	return scnprintf(buf, PAGE_SIZE, "cmbloc : x%08x\ncmbsz  : x%08x\n",
1801		       ndev->cmbloc, ndev->cmbsz);
1802}
1803static DEVICE_ATTR(cmb, S_IRUGO, nvme_cmb_show, NULL);
1804
1805static u64 nvme_cmb_size_unit(struct nvme_dev *dev)
1806{
1807	u8 szu = (dev->cmbsz >> NVME_CMBSZ_SZU_SHIFT) & NVME_CMBSZ_SZU_MASK;
1808
1809	return 1ULL << (12 + 4 * szu);
1810}
1811
1812static u32 nvme_cmb_size(struct nvme_dev *dev)
1813{
1814	return (dev->cmbsz >> NVME_CMBSZ_SZ_SHIFT) & NVME_CMBSZ_SZ_MASK;
1815}
1816
1817static void nvme_map_cmb(struct nvme_dev *dev)
1818{
1819	u64 size, offset;
1820	resource_size_t bar_size;
1821	struct pci_dev *pdev = to_pci_dev(dev->dev);
1822	int bar;
1823
1824	if (dev->cmb_size)
1825		return;
1826
1827	if (NVME_CAP_CMBS(dev->ctrl.cap))
1828		writel(NVME_CMBMSC_CRE, dev->bar + NVME_REG_CMBMSC);
1829
1830	dev->cmbsz = readl(dev->bar + NVME_REG_CMBSZ);
1831	if (!dev->cmbsz)
1832		return;
1833	dev->cmbloc = readl(dev->bar + NVME_REG_CMBLOC);
1834
1835	size = nvme_cmb_size_unit(dev) * nvme_cmb_size(dev);
1836	offset = nvme_cmb_size_unit(dev) * NVME_CMB_OFST(dev->cmbloc);
1837	bar = NVME_CMB_BIR(dev->cmbloc);
1838	bar_size = pci_resource_len(pdev, bar);
1839
1840	if (offset > bar_size)
1841		return;
1842
1843	/*
1844	 * Tell the controller about the host side address mapping the CMB,
1845	 * and enable CMB decoding for the NVMe 1.4+ scheme:
1846	 */
1847	if (NVME_CAP_CMBS(dev->ctrl.cap)) {
1848		hi_lo_writeq(NVME_CMBMSC_CRE | NVME_CMBMSC_CMSE |
1849			     (pci_bus_address(pdev, bar) + offset),
1850			     dev->bar + NVME_REG_CMBMSC);
1851	}
1852
1853	/*
1854	 * Controllers may support a CMB size larger than their BAR,
1855	 * for example, due to being behind a bridge. Reduce the CMB to
1856	 * the reported size of the BAR
1857	 */
1858	if (size > bar_size - offset)
1859		size = bar_size - offset;
1860
1861	if (pci_p2pdma_add_resource(pdev, bar, size, offset)) {
1862		dev_warn(dev->ctrl.device,
1863			 "failed to register the CMB\n");
1864		return;
1865	}
1866
1867	dev->cmb_size = size;
1868	dev->cmb_use_sqes = use_cmb_sqes && (dev->cmbsz & NVME_CMBSZ_SQS);
1869
1870	if ((dev->cmbsz & (NVME_CMBSZ_WDS | NVME_CMBSZ_RDS)) ==
1871			(NVME_CMBSZ_WDS | NVME_CMBSZ_RDS))
1872		pci_p2pmem_publish(pdev, true);
1873
1874	if (sysfs_add_file_to_group(&dev->ctrl.device->kobj,
1875				    &dev_attr_cmb.attr, NULL))
1876		dev_warn(dev->ctrl.device,
1877			 "failed to add sysfs attribute for CMB\n");
1878}
1879
1880static inline void nvme_release_cmb(struct nvme_dev *dev)
1881{
1882	if (dev->cmb_size) {
1883		sysfs_remove_file_from_group(&dev->ctrl.device->kobj,
1884					     &dev_attr_cmb.attr, NULL);
1885		dev->cmb_size = 0;
1886	}
1887}
1888
1889static int nvme_set_host_mem(struct nvme_dev *dev, u32 bits)
1890{
1891	u32 host_mem_size = dev->host_mem_size >> NVME_CTRL_PAGE_SHIFT;
1892	u64 dma_addr = dev->host_mem_descs_dma;
1893	struct nvme_command c;
1894	int ret;
1895
1896	memset(&c, 0, sizeof(c));
1897	c.features.opcode	= nvme_admin_set_features;
1898	c.features.fid		= cpu_to_le32(NVME_FEAT_HOST_MEM_BUF);
1899	c.features.dword11	= cpu_to_le32(bits);
1900	c.features.dword12	= cpu_to_le32(host_mem_size);
1901	c.features.dword13	= cpu_to_le32(lower_32_bits(dma_addr));
1902	c.features.dword14	= cpu_to_le32(upper_32_bits(dma_addr));
1903	c.features.dword15	= cpu_to_le32(dev->nr_host_mem_descs);
1904
1905	ret = nvme_submit_sync_cmd(dev->ctrl.admin_q, &c, NULL, 0);
1906	if (ret) {
1907		dev_warn(dev->ctrl.device,
1908			 "failed to set host mem (err %d, flags %#x).\n",
1909			 ret, bits);
1910	}
1911	return ret;
1912}
1913
1914static void nvme_free_host_mem(struct nvme_dev *dev)
1915{
1916	int i;
1917
1918	for (i = 0; i < dev->nr_host_mem_descs; i++) {
1919		struct nvme_host_mem_buf_desc *desc = &dev->host_mem_descs[i];
1920		size_t size = le32_to_cpu(desc->size) * NVME_CTRL_PAGE_SIZE;
1921
1922		dma_free_attrs(dev->dev, size, dev->host_mem_desc_bufs[i],
1923			       le64_to_cpu(desc->addr),
1924			       DMA_ATTR_NO_KERNEL_MAPPING | DMA_ATTR_NO_WARN);
1925	}
1926
1927	kfree(dev->host_mem_desc_bufs);
1928	dev->host_mem_desc_bufs = NULL;
1929	dma_free_coherent(dev->dev,
1930			dev->nr_host_mem_descs * sizeof(*dev->host_mem_descs),
1931			dev->host_mem_descs, dev->host_mem_descs_dma);
1932	dev->host_mem_descs = NULL;
1933	dev->nr_host_mem_descs = 0;
1934}
1935
1936static int __nvme_alloc_host_mem(struct nvme_dev *dev, u64 preferred,
1937		u32 chunk_size)
1938{
1939	struct nvme_host_mem_buf_desc *descs;
1940	u32 max_entries, len;
1941	dma_addr_t descs_dma;
1942	int i = 0;
1943	void **bufs;
1944	u64 size, tmp;
1945
1946	tmp = (preferred + chunk_size - 1);
1947	do_div(tmp, chunk_size);
1948	max_entries = tmp;
1949
1950	if (dev->ctrl.hmmaxd && dev->ctrl.hmmaxd < max_entries)
1951		max_entries = dev->ctrl.hmmaxd;
1952
1953	descs = dma_alloc_coherent(dev->dev, max_entries * sizeof(*descs),
1954				   &descs_dma, GFP_KERNEL);
1955	if (!descs)
1956		goto out;
1957
1958	bufs = kcalloc(max_entries, sizeof(*bufs), GFP_KERNEL);
1959	if (!bufs)
1960		goto out_free_descs;
1961
1962	for (size = 0; size < preferred && i < max_entries; size += len) {
1963		dma_addr_t dma_addr;
1964
1965		len = min_t(u64, chunk_size, preferred - size);
1966		bufs[i] = dma_alloc_attrs(dev->dev, len, &dma_addr, GFP_KERNEL,
1967				DMA_ATTR_NO_KERNEL_MAPPING | DMA_ATTR_NO_WARN);
1968		if (!bufs[i])
1969			break;
1970
1971		descs[i].addr = cpu_to_le64(dma_addr);
1972		descs[i].size = cpu_to_le32(len / NVME_CTRL_PAGE_SIZE);
1973		i++;
1974	}
1975
1976	if (!size)
1977		goto out_free_bufs;
1978
1979	dev->nr_host_mem_descs = i;
1980	dev->host_mem_size = size;
1981	dev->host_mem_descs = descs;
1982	dev->host_mem_descs_dma = descs_dma;
1983	dev->host_mem_desc_bufs = bufs;
1984	return 0;
1985
1986out_free_bufs:
1987	while (--i >= 0) {
1988		size_t size = le32_to_cpu(descs[i].size) * NVME_CTRL_PAGE_SIZE;
1989
1990		dma_free_attrs(dev->dev, size, bufs[i],
1991			       le64_to_cpu(descs[i].addr),
1992			       DMA_ATTR_NO_KERNEL_MAPPING | DMA_ATTR_NO_WARN);
1993	}
1994
1995	kfree(bufs);
1996out_free_descs:
1997	dma_free_coherent(dev->dev, max_entries * sizeof(*descs), descs,
1998			descs_dma);
1999out:
2000	dev->host_mem_descs = NULL;
2001	return -ENOMEM;
2002}
2003
2004static int nvme_alloc_host_mem(struct nvme_dev *dev, u64 min, u64 preferred)
2005{
2006	u64 min_chunk = min_t(u64, preferred, PAGE_SIZE * MAX_ORDER_NR_PAGES);
2007	u64 hmminds = max_t(u32, dev->ctrl.hmminds * 4096, PAGE_SIZE * 2);
2008	u64 chunk_size;
2009
2010	/* start big and work our way down */
2011	for (chunk_size = min_chunk; chunk_size >= hmminds; chunk_size /= 2) {
2012		if (!__nvme_alloc_host_mem(dev, preferred, chunk_size)) {
2013			if (!min || dev->host_mem_size >= min)
2014				return 0;
2015			nvme_free_host_mem(dev);
2016		}
2017	}
2018
2019	return -ENOMEM;
2020}
2021
2022static int nvme_setup_host_mem(struct nvme_dev *dev)
2023{
2024	u64 max = (u64)max_host_mem_size_mb * SZ_1M;
2025	u64 preferred = (u64)dev->ctrl.hmpre * 4096;
2026	u64 min = (u64)dev->ctrl.hmmin * 4096;
2027	u32 enable_bits = NVME_HOST_MEM_ENABLE;
2028	int ret;
2029
2030	preferred = min(preferred, max);
2031	if (min > max) {
2032		dev_warn(dev->ctrl.device,
2033			"min host memory (%lld MiB) above limit (%d MiB).\n",
2034			min >> ilog2(SZ_1M), max_host_mem_size_mb);
2035		nvme_free_host_mem(dev);
2036		return 0;
2037	}
2038
2039	/*
2040	 * If we already have a buffer allocated check if we can reuse it.
2041	 */
2042	if (dev->host_mem_descs) {
2043		if (dev->host_mem_size >= min)
2044			enable_bits |= NVME_HOST_MEM_RETURN;
2045		else
2046			nvme_free_host_mem(dev);
2047	}
2048
2049	if (!dev->host_mem_descs) {
2050		if (nvme_alloc_host_mem(dev, min, preferred)) {
2051			dev_warn(dev->ctrl.device,
2052				"failed to allocate host memory buffer.\n");
2053			return 0; /* controller must work without HMB */
2054		}
2055
2056		dev_info(dev->ctrl.device,
2057			"allocated %lld MiB host memory buffer.\n",
2058			dev->host_mem_size >> ilog2(SZ_1M));
2059	}
2060
2061	ret = nvme_set_host_mem(dev, enable_bits);
2062	if (ret)
2063		nvme_free_host_mem(dev);
2064	return ret;
2065}
2066
2067/*
2068 * nirqs is the number of interrupts available for write and read
2069 * queues. The core already reserved an interrupt for the admin queue.
2070 */
2071static void nvme_calc_irq_sets(struct irq_affinity *affd, unsigned int nrirqs)
2072{
2073	struct nvme_dev *dev = affd->priv;
2074	unsigned int nr_read_queues, nr_write_queues = dev->nr_write_queues;
2075
2076	/*
2077	 * If there is no interrupt available for queues, ensure that
2078	 * the default queue is set to 1. The affinity set size is
2079	 * also set to one, but the irq core ignores it for this case.
2080	 *
2081	 * If only one interrupt is available or 'write_queue' == 0, combine
2082	 * write and read queues.
2083	 *
2084	 * If 'write_queues' > 0, ensure it leaves room for at least one read
2085	 * queue.
2086	 */
2087	if (!nrirqs) {
2088		nrirqs = 1;
2089		nr_read_queues = 0;
2090	} else if (nrirqs == 1 || !nr_write_queues) {
2091		nr_read_queues = 0;
2092	} else if (nr_write_queues >= nrirqs) {
2093		nr_read_queues = 1;
2094	} else {
2095		nr_read_queues = nrirqs - nr_write_queues;
2096	}
2097
2098	dev->io_queues[HCTX_TYPE_DEFAULT] = nrirqs - nr_read_queues;
2099	affd->set_size[HCTX_TYPE_DEFAULT] = nrirqs - nr_read_queues;
2100	dev->io_queues[HCTX_TYPE_READ] = nr_read_queues;
2101	affd->set_size[HCTX_TYPE_READ] = nr_read_queues;
2102	affd->nr_sets = nr_read_queues ? 2 : 1;
2103}
2104
2105static int nvme_setup_irqs(struct nvme_dev *dev, unsigned int nr_io_queues)
2106{
2107	struct pci_dev *pdev = to_pci_dev(dev->dev);
2108	struct irq_affinity affd = {
2109		.pre_vectors	= 1,
2110		.calc_sets	= nvme_calc_irq_sets,
2111		.priv		= dev,
2112	};
2113	unsigned int irq_queues, poll_queues;
2114
2115	/*
2116	 * Poll queues don't need interrupts, but we need at least one I/O queue
2117	 * left over for non-polled I/O.
2118	 */
2119	poll_queues = min(dev->nr_poll_queues, nr_io_queues - 1);
2120	dev->io_queues[HCTX_TYPE_POLL] = poll_queues;
2121
2122	/*
2123	 * Initialize for the single interrupt case, will be updated in
2124	 * nvme_calc_irq_sets().
2125	 */
2126	dev->io_queues[HCTX_TYPE_DEFAULT] = 1;
2127	dev->io_queues[HCTX_TYPE_READ] = 0;
2128
2129	/*
2130	 * We need interrupts for the admin queue and each non-polled I/O queue,
2131	 * but some Apple controllers require all queues to use the first
2132	 * vector.
2133	 */
2134	irq_queues = 1;
2135	if (!(dev->ctrl.quirks & NVME_QUIRK_SINGLE_VECTOR))
2136		irq_queues += (nr_io_queues - poll_queues);
2137	return pci_alloc_irq_vectors_affinity(pdev, 1, irq_queues,
2138			      PCI_IRQ_ALL_TYPES | PCI_IRQ_AFFINITY, &affd);
2139}
2140
2141static void nvme_disable_io_queues(struct nvme_dev *dev)
2142{
2143	if (__nvme_disable_io_queues(dev, nvme_admin_delete_sq))
2144		__nvme_disable_io_queues(dev, nvme_admin_delete_cq);
2145}
2146
2147static unsigned int nvme_max_io_queues(struct nvme_dev *dev)
2148{
2149	return num_possible_cpus() + dev->nr_write_queues + dev->nr_poll_queues;
2150}
2151
2152static int nvme_setup_io_queues(struct nvme_dev *dev)
2153{
2154	struct nvme_queue *adminq = &dev->queues[0];
2155	struct pci_dev *pdev = to_pci_dev(dev->dev);
2156	unsigned int nr_io_queues;
2157	unsigned long size;
2158	int result;
2159
2160	/*
2161	 * Sample the module parameters once at reset time so that we have
2162	 * stable values to work with.
2163	 */
2164	dev->nr_write_queues = write_queues;
2165	dev->nr_poll_queues = poll_queues;
2166
2167	/*
2168	 * If tags are shared with admin queue (Apple bug), then
2169	 * make sure we only use one IO queue.
2170	 */
2171	if (dev->ctrl.quirks & NVME_QUIRK_SHARED_TAGS)
2172		nr_io_queues = 1;
2173	else
2174		nr_io_queues = min(nvme_max_io_queues(dev),
2175				   dev->nr_allocated_queues - 1);
2176
2177	result = nvme_set_queue_count(&dev->ctrl, &nr_io_queues);
2178	if (result < 0)
2179		return result;
2180
2181	if (nr_io_queues == 0)
2182		return 0;
2183
2184	clear_bit(NVMEQ_ENABLED, &adminq->flags);
2185
2186	if (dev->cmb_use_sqes) {
2187		result = nvme_cmb_qdepth(dev, nr_io_queues,
2188				sizeof(struct nvme_command));
2189		if (result > 0)
2190			dev->q_depth = result;
2191		else
2192			dev->cmb_use_sqes = false;
2193	}
2194
2195	do {
2196		size = db_bar_size(dev, nr_io_queues);
2197		result = nvme_remap_bar(dev, size);
2198		if (!result)
2199			break;
2200		if (!--nr_io_queues)
2201			return -ENOMEM;
2202	} while (1);
2203	adminq->q_db = dev->dbs;
2204
2205 retry:
2206	/* Deregister the admin queue's interrupt */
2207	pci_free_irq(pdev, 0, adminq);
2208
2209	/*
2210	 * If we enable msix early due to not intx, disable it again before
2211	 * setting up the full range we need.
2212	 */
2213	pci_free_irq_vectors(pdev);
2214
2215	result = nvme_setup_irqs(dev, nr_io_queues);
2216	if (result <= 0)
2217		return -EIO;
2218
2219	dev->num_vecs = result;
2220	result = max(result - 1, 1);
2221	dev->max_qid = result + dev->io_queues[HCTX_TYPE_POLL];
2222
2223	/*
2224	 * Should investigate if there's a performance win from allocating
2225	 * more queues than interrupt vectors; it might allow the submission
2226	 * path to scale better, even if the receive path is limited by the
2227	 * number of interrupts.
2228	 */
2229	result = queue_request_irq(adminq);
2230	if (result)
2231		return result;
2232	set_bit(NVMEQ_ENABLED, &adminq->flags);
2233
2234	result = nvme_create_io_queues(dev);
2235	if (result || dev->online_queues < 2)
2236		return result;
2237
2238	if (dev->online_queues - 1 < dev->max_qid) {
2239		nr_io_queues = dev->online_queues - 1;
2240		nvme_disable_io_queues(dev);
2241		nvme_suspend_io_queues(dev);
2242		goto retry;
2243	}
2244	dev_info(dev->ctrl.device, "%d/%d/%d default/read/poll queues\n",
2245					dev->io_queues[HCTX_TYPE_DEFAULT],
2246					dev->io_queues[HCTX_TYPE_READ],
2247					dev->io_queues[HCTX_TYPE_POLL]);
2248	return 0;
2249}
2250
2251static void nvme_del_queue_end(struct request *req, blk_status_t error)
2252{
2253	struct nvme_queue *nvmeq = req->end_io_data;
2254
2255	blk_mq_free_request(req);
2256	complete(&nvmeq->delete_done);
2257}
2258
2259static void nvme_del_cq_end(struct request *req, blk_status_t error)
2260{
2261	struct nvme_queue *nvmeq = req->end_io_data;
2262
2263	if (error)
2264		set_bit(NVMEQ_DELETE_ERROR, &nvmeq->flags);
2265
2266	nvme_del_queue_end(req, error);
2267}
2268
2269static int nvme_delete_queue(struct nvme_queue *nvmeq, u8 opcode)
2270{
2271	struct request_queue *q = nvmeq->dev->ctrl.admin_q;
2272	struct request *req;
2273	struct nvme_command cmd;
2274
2275	memset(&cmd, 0, sizeof(cmd));
2276	cmd.delete_queue.opcode = opcode;
2277	cmd.delete_queue.qid = cpu_to_le16(nvmeq->qid);
2278
2279	req = nvme_alloc_request(q, &cmd, BLK_MQ_REQ_NOWAIT);
2280	if (IS_ERR(req))
2281		return PTR_ERR(req);
2282
2283	req->end_io_data = nvmeq;
2284
2285	init_completion(&nvmeq->delete_done);
2286	blk_execute_rq_nowait(q, NULL, req, false,
2287			opcode == nvme_admin_delete_cq ?
2288				nvme_del_cq_end : nvme_del_queue_end);
2289	return 0;
2290}
2291
2292static bool __nvme_disable_io_queues(struct nvme_dev *dev, u8 opcode)
2293{
2294	int nr_queues = dev->online_queues - 1, sent = 0;
2295	unsigned long timeout;
2296
2297 retry:
2298	timeout = ADMIN_TIMEOUT;
2299	while (nr_queues > 0) {
2300		if (nvme_delete_queue(&dev->queues[nr_queues], opcode))
2301			break;
2302		nr_queues--;
2303		sent++;
2304	}
2305	while (sent) {
2306		struct nvme_queue *nvmeq = &dev->queues[nr_queues + sent];
2307
2308		timeout = wait_for_completion_io_timeout(&nvmeq->delete_done,
2309				timeout);
2310		if (timeout == 0)
2311			return false;
2312
2313		sent--;
2314		if (nr_queues)
2315			goto retry;
2316	}
2317	return true;
2318}
2319
2320static void nvme_dev_add(struct nvme_dev *dev)
2321{
2322	int ret;
2323
2324	if (!dev->ctrl.tagset) {
2325		dev->tagset.ops = &nvme_mq_ops;
2326		dev->tagset.nr_hw_queues = dev->online_queues - 1;
2327		dev->tagset.nr_maps = 2; /* default + read */
2328		if (dev->io_queues[HCTX_TYPE_POLL])
2329			dev->tagset.nr_maps++;
2330		dev->tagset.timeout = NVME_IO_TIMEOUT;
2331		dev->tagset.numa_node = dev->ctrl.numa_node;
2332		dev->tagset.queue_depth = min_t(unsigned int, dev->q_depth,
2333						BLK_MQ_MAX_DEPTH) - 1;
2334		dev->tagset.cmd_size = sizeof(struct nvme_iod);
2335		dev->tagset.flags = BLK_MQ_F_SHOULD_MERGE;
2336		dev->tagset.driver_data = dev;
2337
2338		/*
2339		 * Some Apple controllers requires tags to be unique
2340		 * across admin and IO queue, so reserve the first 32
2341		 * tags of the IO queue.
2342		 */
2343		if (dev->ctrl.quirks & NVME_QUIRK_SHARED_TAGS)
2344			dev->tagset.reserved_tags = NVME_AQ_DEPTH;
2345
2346		ret = blk_mq_alloc_tag_set(&dev->tagset);
2347		if (ret) {
2348			dev_warn(dev->ctrl.device,
2349				"IO queues tagset allocation failed %d\n", ret);
2350			return;
2351		}
2352		dev->ctrl.tagset = &dev->tagset;
2353	} else {
2354		blk_mq_update_nr_hw_queues(&dev->tagset, dev->online_queues - 1);
2355
2356		/* Free previously allocated queues that are no longer usable */
2357		nvme_free_queues(dev, dev->online_queues);
2358	}
2359
2360	nvme_dbbuf_set(dev);
2361}
2362
2363static int nvme_pci_enable(struct nvme_dev *dev)
2364{
2365	int result = -ENOMEM;
2366	struct pci_dev *pdev = to_pci_dev(dev->dev);
2367
2368	if (pci_enable_device_mem(pdev))
2369		return result;
2370
2371	pci_set_master(pdev);
2372
2373	if (dma_set_mask_and_coherent(dev->dev, DMA_BIT_MASK(64)))
2374		goto disable;
2375
2376	if (readl(dev->bar + NVME_REG_CSTS) == -1) {
2377		result = -ENODEV;
2378		goto disable;
2379	}
2380
2381	/*
2382	 * Some devices and/or platforms don't advertise or work with INTx
2383	 * interrupts. Pre-enable a single MSIX or MSI vec for setup. We'll
2384	 * adjust this later.
2385	 */
2386	result = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
2387	if (result < 0)
2388		return result;
2389
2390	dev->ctrl.cap = lo_hi_readq(dev->bar + NVME_REG_CAP);
2391
2392	dev->q_depth = min_t(u32, NVME_CAP_MQES(dev->ctrl.cap) + 1,
2393				io_queue_depth);
2394	dev->ctrl.sqsize = dev->q_depth - 1; /* 0's based queue depth */
2395	dev->db_stride = 1 << NVME_CAP_STRIDE(dev->ctrl.cap);
2396	dev->dbs = dev->bar + 4096;
2397
2398	/*
2399	 * Some Apple controllers require a non-standard SQE size.
2400	 * Interestingly they also seem to ignore the CC:IOSQES register
2401	 * so we don't bother updating it here.
2402	 */
2403	if (dev->ctrl.quirks & NVME_QUIRK_128_BYTES_SQES)
2404		dev->io_sqes = 7;
2405	else
2406		dev->io_sqes = NVME_NVM_IOSQES;
2407
2408	/*
2409	 * Temporary fix for the Apple controller found in the MacBook8,1 and
2410	 * some MacBook7,1 to avoid controller resets and data loss.
2411	 */
2412	if (pdev->vendor == PCI_VENDOR_ID_APPLE && pdev->device == 0x2001) {
2413		dev->q_depth = 2;
2414		dev_warn(dev->ctrl.device, "detected Apple NVMe controller, "
2415			"set queue depth=%u to work around controller resets\n",
2416			dev->q_depth);
2417	} else if (pdev->vendor == PCI_VENDOR_ID_SAMSUNG &&
2418		   (pdev->device == 0xa821 || pdev->device == 0xa822) &&
2419		   NVME_CAP_MQES(dev->ctrl.cap) == 0) {
2420		dev->q_depth = 64;
2421		dev_err(dev->ctrl.device, "detected PM1725 NVMe controller, "
2422                        "set queue depth=%u\n", dev->q_depth);
2423	}
2424
2425	/*
2426	 * Controllers with the shared tags quirk need the IO queue to be
2427	 * big enough so that we get 32 tags for the admin queue
2428	 */
2429	if ((dev->ctrl.quirks & NVME_QUIRK_SHARED_TAGS) &&
2430	    (dev->q_depth < (NVME_AQ_DEPTH + 2))) {
2431		dev->q_depth = NVME_AQ_DEPTH + 2;
2432		dev_warn(dev->ctrl.device, "IO queue depth clamped to %d\n",
2433			 dev->q_depth);
2434	}
2435
2436
2437	nvme_map_cmb(dev);
2438
2439	pci_enable_pcie_error_reporting(pdev);
2440	pci_save_state(pdev);
2441	return 0;
2442
2443 disable:
2444	pci_disable_device(pdev);
2445	return result;
2446}
2447
2448static void nvme_dev_unmap(struct nvme_dev *dev)
2449{
2450	if (dev->bar)
2451		iounmap(dev->bar);
2452	pci_release_mem_regions(to_pci_dev(dev->dev));
2453}
2454
2455static void nvme_pci_disable(struct nvme_dev *dev)
2456{
2457	struct pci_dev *pdev = to_pci_dev(dev->dev);
2458
2459	pci_free_irq_vectors(pdev);
2460
2461	if (pci_is_enabled(pdev)) {
2462		pci_disable_pcie_error_reporting(pdev);
2463		pci_disable_device(pdev);
2464	}
2465}
2466
2467static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown)
2468{
2469	bool dead = true, freeze = false;
2470	struct pci_dev *pdev = to_pci_dev(dev->dev);
2471
2472	mutex_lock(&dev->shutdown_lock);
2473	if (pci_is_enabled(pdev)) {
2474		u32 csts = readl(dev->bar + NVME_REG_CSTS);
2475
2476		if (dev->ctrl.state == NVME_CTRL_LIVE ||
2477		    dev->ctrl.state == NVME_CTRL_RESETTING) {
2478			freeze = true;
2479			nvme_start_freeze(&dev->ctrl);
2480		}
2481		dead = !!((csts & NVME_CSTS_CFS) || !(csts & NVME_CSTS_RDY) ||
2482			pdev->error_state  != pci_channel_io_normal);
2483	}
2484
2485	/*
2486	 * Give the controller a chance to complete all entered requests if
2487	 * doing a safe shutdown.
2488	 */
2489	if (!dead && shutdown && freeze)
2490		nvme_wait_freeze_timeout(&dev->ctrl, NVME_IO_TIMEOUT);
2491
2492	nvme_stop_queues(&dev->ctrl);
2493
2494	if (!dead && dev->ctrl.queue_count > 0) {
2495		nvme_disable_io_queues(dev);
2496		nvme_disable_admin_queue(dev, shutdown);
2497	}
2498	nvme_suspend_io_queues(dev);
2499	nvme_suspend_queue(&dev->queues[0]);
2500	nvme_pci_disable(dev);
2501	nvme_reap_pending_cqes(dev);
2502
2503	blk_mq_tagset_busy_iter(&dev->tagset, nvme_cancel_request, &dev->ctrl);
2504	blk_mq_tagset_busy_iter(&dev->admin_tagset, nvme_cancel_request, &dev->ctrl);
2505	blk_mq_tagset_wait_completed_request(&dev->tagset);
2506	blk_mq_tagset_wait_completed_request(&dev->admin_tagset);
2507
2508	/*
2509	 * The driver will not be starting up queues again if shutting down so
2510	 * must flush all entered requests to their failed completion to avoid
2511	 * deadlocking blk-mq hot-cpu notifier.
2512	 */
2513	if (shutdown) {
2514		nvme_start_queues(&dev->ctrl);
2515		if (dev->ctrl.admin_q && !blk_queue_dying(dev->ctrl.admin_q))
2516			nvme_start_admin_queue(&dev->ctrl);
2517	}
2518	mutex_unlock(&dev->shutdown_lock);
2519}
2520
2521static int nvme_disable_prepare_reset(struct nvme_dev *dev, bool shutdown)
2522{
2523	if (!nvme_wait_reset(&dev->ctrl))
2524		return -EBUSY;
2525	nvme_dev_disable(dev, shutdown);
2526	return 0;
2527}
2528
2529static int nvme_setup_prp_pools(struct nvme_dev *dev)
2530{
2531	dev->prp_page_pool = dma_pool_create("prp list page", dev->dev,
2532						NVME_CTRL_PAGE_SIZE,
2533						NVME_CTRL_PAGE_SIZE, 0);
2534	if (!dev->prp_page_pool)
2535		return -ENOMEM;
2536
2537	/* Optimisation for I/Os between 4k and 128k */
2538	dev->prp_small_pool = dma_pool_create("prp list 256", dev->dev,
2539						256, 256, 0);
2540	if (!dev->prp_small_pool) {
2541		dma_pool_destroy(dev->prp_page_pool);
2542		return -ENOMEM;
2543	}
2544	return 0;
2545}
2546
2547static void nvme_release_prp_pools(struct nvme_dev *dev)
2548{
2549	dma_pool_destroy(dev->prp_page_pool);
2550	dma_pool_destroy(dev->prp_small_pool);
2551}
2552
2553static int nvme_pci_alloc_iod_mempool(struct nvme_dev *dev)
2554{
2555	size_t npages = max(nvme_pci_npages_prp(), nvme_pci_npages_sgl());
2556	size_t alloc_size = sizeof(__le64 *) * npages +
2557			    sizeof(struct scatterlist) * NVME_MAX_SEGS;
2558
2559	WARN_ON_ONCE(alloc_size > PAGE_SIZE);
2560	dev->iod_mempool = mempool_create_node(1,
2561			mempool_kmalloc, mempool_kfree,
2562			(void *)alloc_size, GFP_KERNEL,
2563			dev_to_node(dev->dev));
2564	if (!dev->iod_mempool)
2565		return -ENOMEM;
2566	return 0;
2567}
2568
2569static void nvme_free_tagset(struct nvme_dev *dev)
2570{
2571	if (dev->tagset.tags)
2572		blk_mq_free_tag_set(&dev->tagset);
2573	dev->ctrl.tagset = NULL;
2574}
2575
2576/* pairs with nvme_pci_alloc_dev */
2577static void nvme_pci_free_ctrl(struct nvme_ctrl *ctrl)
2578{
2579	struct nvme_dev *dev = to_nvme_dev(ctrl);
2580
2581	nvme_dbbuf_dma_free(dev);
2582	nvme_free_tagset(dev);
2583	if (dev->ctrl.admin_q)
2584		blk_put_queue(dev->ctrl.admin_q);
2585	free_opal_dev(dev->ctrl.opal_dev);
2586	mempool_destroy(dev->iod_mempool);
2587	put_device(dev->dev);
2588	kfree(dev->queues);
2589	kfree(dev);
2590}
2591
2592static void nvme_remove_dead_ctrl(struct nvme_dev *dev)
2593{
2594	/*
2595	 * Set state to deleting now to avoid blocking nvme_wait_reset(), which
2596	 * may be holding this pci_dev's device lock.
2597	 */
2598	nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DELETING);
2599	nvme_get_ctrl(&dev->ctrl);
2600	nvme_dev_disable(dev, false);
2601	nvme_kill_queues(&dev->ctrl);
2602	if (!queue_work(nvme_wq, &dev->remove_work))
2603		nvme_put_ctrl(&dev->ctrl);
2604}
2605
2606static void nvme_reset_work(struct work_struct *work)
2607{
2608	struct nvme_dev *dev =
2609		container_of(work, struct nvme_dev, ctrl.reset_work);
2610	bool was_suspend = !!(dev->ctrl.ctrl_config & NVME_CC_SHN_NORMAL);
2611	int result;
2612
2613	if (dev->ctrl.state != NVME_CTRL_RESETTING) {
2614		dev_warn(dev->ctrl.device, "ctrl state %d is not RESETTING\n",
2615			 dev->ctrl.state);
2616		result = -ENODEV;
2617		goto out;
2618	}
2619
2620	/*
2621	 * If we're called to reset a live controller first shut it down before
2622	 * moving on.
2623	 */
2624	if (dev->ctrl.ctrl_config & NVME_CC_ENABLE)
2625		nvme_dev_disable(dev, false);
2626	nvme_sync_queues(&dev->ctrl);
2627
2628	mutex_lock(&dev->shutdown_lock);
2629	result = nvme_pci_enable(dev);
2630	if (result)
2631		goto out_unlock;
2632
2633	result = nvme_pci_configure_admin_queue(dev);
2634	if (result)
2635		goto out_unlock;
2636
2637	result = nvme_alloc_admin_tags(dev);
2638	if (result)
2639		goto out_unlock;
2640
2641	dma_set_min_align_mask(dev->dev, NVME_CTRL_PAGE_SIZE - 1);
2642
2643	/*
2644	 * Limit the max command size to prevent iod->sg allocations going
2645	 * over a single page.
2646	 */
2647	dev->ctrl.max_hw_sectors = min_t(u32,
2648		NVME_MAX_KB_SZ << 1, dma_max_mapping_size(dev->dev) >> 9);
2649	dev->ctrl.max_segments = NVME_MAX_SEGS;
2650
2651	/*
2652	 * Don't limit the IOMMU merged segment size.
2653	 */
2654	dma_set_max_seg_size(dev->dev, 0xffffffff);
2655
2656	mutex_unlock(&dev->shutdown_lock);
2657
2658	/*
2659	 * Introduce CONNECTING state from nvme-fc/rdma transports to mark the
2660	 * initializing procedure here.
2661	 */
2662	if (!nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_CONNECTING)) {
2663		dev_warn(dev->ctrl.device,
2664			"failed to mark controller CONNECTING\n");
2665		result = -EBUSY;
2666		goto out;
2667	}
2668
2669	/*
2670	 * We do not support an SGL for metadata (yet), so we are limited to a
2671	 * single integrity segment for the separate metadata pointer.
2672	 */
2673	dev->ctrl.max_integrity_segments = 1;
2674
2675	result = nvme_init_identify(&dev->ctrl);
2676	if (result)
2677		goto out;
2678
2679	if (dev->ctrl.oacs & NVME_CTRL_OACS_SEC_SUPP) {
2680		if (!dev->ctrl.opal_dev)
2681			dev->ctrl.opal_dev =
2682				init_opal_dev(&dev->ctrl, &nvme_sec_submit);
2683		else if (was_suspend)
2684			opal_unlock_from_suspend(dev->ctrl.opal_dev);
2685	} else {
2686		free_opal_dev(dev->ctrl.opal_dev);
2687		dev->ctrl.opal_dev = NULL;
2688	}
2689
2690	if (dev->ctrl.oacs & NVME_CTRL_OACS_DBBUF_SUPP) {
2691		result = nvme_dbbuf_dma_alloc(dev);
2692		if (result)
2693			dev_warn(dev->dev,
2694				 "unable to allocate dma for dbbuf\n");
2695	}
2696
2697	if (dev->ctrl.hmpre) {
2698		result = nvme_setup_host_mem(dev);
2699		if (result < 0)
2700			goto out;
2701	}
2702
2703	result = nvme_setup_io_queues(dev);
2704	if (result)
2705		goto out;
2706
2707	/*
2708	 * Keep the controller around but remove all namespaces if we don't have
2709	 * any working I/O queue.
2710	 */
2711	if (dev->online_queues < 2) {
2712		dev_warn(dev->ctrl.device, "IO queues not created\n");
2713		nvme_kill_queues(&dev->ctrl);
2714		nvme_remove_namespaces(&dev->ctrl);
2715		nvme_free_tagset(dev);
2716	} else {
2717		nvme_start_queues(&dev->ctrl);
2718		nvme_wait_freeze(&dev->ctrl);
2719		nvme_dev_add(dev);
2720		nvme_unfreeze(&dev->ctrl);
2721	}
2722
2723	/*
2724	 * If only admin queue live, keep it to do further investigation or
2725	 * recovery.
2726	 */
2727	if (!nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_LIVE)) {
2728		dev_warn(dev->ctrl.device,
2729			"failed to mark controller live state\n");
2730		result = -ENODEV;
2731		goto out;
2732	}
2733
2734	nvme_start_ctrl(&dev->ctrl);
2735	return;
2736
2737 out_unlock:
2738	mutex_unlock(&dev->shutdown_lock);
2739 out:
2740	if (result)
2741		dev_warn(dev->ctrl.device,
2742			 "Removing after probe failure status: %d\n", result);
2743	nvme_remove_dead_ctrl(dev);
2744}
2745
2746static void nvme_remove_dead_ctrl_work(struct work_struct *work)
2747{
2748	struct nvme_dev *dev = container_of(work, struct nvme_dev, remove_work);
2749	struct pci_dev *pdev = to_pci_dev(dev->dev);
2750
2751	if (pci_get_drvdata(pdev))
2752		device_release_driver(&pdev->dev);
2753	nvme_put_ctrl(&dev->ctrl);
2754}
2755
2756static int nvme_pci_reg_read32(struct nvme_ctrl *ctrl, u32 off, u32 *val)
2757{
2758	*val = readl(to_nvme_dev(ctrl)->bar + off);
2759	return 0;
2760}
2761
2762static int nvme_pci_reg_write32(struct nvme_ctrl *ctrl, u32 off, u32 val)
2763{
2764	writel(val, to_nvme_dev(ctrl)->bar + off);
2765	return 0;
2766}
2767
2768static int nvme_pci_reg_read64(struct nvme_ctrl *ctrl, u32 off, u64 *val)
2769{
2770	*val = lo_hi_readq(to_nvme_dev(ctrl)->bar + off);
2771	return 0;
2772}
2773
2774static int nvme_pci_get_address(struct nvme_ctrl *ctrl, char *buf, int size)
2775{
2776	struct pci_dev *pdev = to_pci_dev(to_nvme_dev(ctrl)->dev);
2777
2778	return snprintf(buf, size, "%s\n", dev_name(&pdev->dev));
2779}
2780
2781static const struct nvme_ctrl_ops nvme_pci_ctrl_ops = {
2782	.name			= "pcie",
2783	.module			= THIS_MODULE,
2784	.flags			= NVME_F_METADATA_SUPPORTED |
2785				  NVME_F_PCI_P2PDMA,
2786	.reg_read32		= nvme_pci_reg_read32,
2787	.reg_write32		= nvme_pci_reg_write32,
2788	.reg_read64		= nvme_pci_reg_read64,
2789	.free_ctrl		= nvme_pci_free_ctrl,
2790	.submit_async_event	= nvme_pci_submit_async_event,
2791	.get_address		= nvme_pci_get_address,
2792};
2793
2794static int nvme_dev_map(struct nvme_dev *dev)
2795{
2796	struct pci_dev *pdev = to_pci_dev(dev->dev);
2797
2798	if (pci_request_mem_regions(pdev, "nvme"))
2799		return -ENODEV;
2800
2801	if (nvme_remap_bar(dev, NVME_REG_DBS + 4096))
2802		goto release;
2803
2804	return 0;
2805  release:
2806	pci_release_mem_regions(pdev);
2807	return -ENODEV;
2808}
2809
2810static unsigned long check_vendor_combination_bug(struct pci_dev *pdev)
2811{
2812	if (pdev->vendor == 0x144d && pdev->device == 0xa802) {
2813		/*
2814		 * Several Samsung devices seem to drop off the PCIe bus
2815		 * randomly when APST is on and uses the deepest sleep state.
2816		 * This has been observed on a Samsung "SM951 NVMe SAMSUNG
2817		 * 256GB", a "PM951 NVMe SAMSUNG 512GB", and a "Samsung SSD
2818		 * 950 PRO 256GB", but it seems to be restricted to two Dell
2819		 * laptops.
2820		 */
2821		if (dmi_match(DMI_SYS_VENDOR, "Dell Inc.") &&
2822		    (dmi_match(DMI_PRODUCT_NAME, "XPS 15 9550") ||
2823		     dmi_match(DMI_PRODUCT_NAME, "Precision 5510")))
2824			return NVME_QUIRK_NO_DEEPEST_PS;
2825	} else if (pdev->vendor == 0x144d && pdev->device == 0xa804) {
2826		/*
2827		 * Samsung SSD 960 EVO drops off the PCIe bus after system
2828		 * suspend on a Ryzen board, ASUS PRIME B350M-A, as well as
2829		 * within few minutes after bootup on a Coffee Lake board -
2830		 * ASUS PRIME Z370-A
2831		 */
2832		if (dmi_match(DMI_BOARD_VENDOR, "ASUSTeK COMPUTER INC.") &&
2833		    (dmi_match(DMI_BOARD_NAME, "PRIME B350M-A") ||
2834		     dmi_match(DMI_BOARD_NAME, "PRIME Z370-A")))
2835			return NVME_QUIRK_NO_APST;
2836	} else if ((pdev->vendor == 0x144d && (pdev->device == 0xa801 ||
2837		    pdev->device == 0xa808 || pdev->device == 0xa809)) ||
2838		   (pdev->vendor == 0x1e0f && pdev->device == 0x0001)) {
2839		/*
2840		 * Forcing to use host managed nvme power settings for
2841		 * lowest idle power with quick resume latency on
2842		 * Samsung and Toshiba SSDs based on suspend behavior
2843		 * on Coffee Lake board for LENOVO C640
2844		 */
2845		if ((dmi_match(DMI_BOARD_VENDOR, "LENOVO")) &&
2846		     dmi_match(DMI_BOARD_NAME, "LNVNB161216"))
2847			return NVME_QUIRK_SIMPLE_SUSPEND;
2848	}
2849
2850	return 0;
2851}
2852
2853static void nvme_async_probe(void *data, async_cookie_t cookie)
2854{
2855	struct nvme_dev *dev = data;
2856
2857	flush_work(&dev->ctrl.reset_work);
2858	flush_work(&dev->ctrl.scan_work);
2859	nvme_put_ctrl(&dev->ctrl);
2860}
2861
2862static struct nvme_dev *nvme_pci_alloc_dev(struct pci_dev *pdev,
2863		const struct pci_device_id *id)
2864{
2865	unsigned long quirks = id->driver_data;
2866	int node = dev_to_node(&pdev->dev);
2867	struct nvme_dev *dev;
2868	int ret = -ENOMEM;
2869
2870	dev = kzalloc_node(sizeof(*dev), GFP_KERNEL, node);
2871	if (!dev)
2872		return ERR_PTR(-ENOMEM);
2873	INIT_WORK(&dev->ctrl.reset_work, nvme_reset_work);
2874	INIT_WORK(&dev->remove_work, nvme_remove_dead_ctrl_work);
2875	mutex_init(&dev->shutdown_lock);
2876
2877	dev->nr_write_queues = write_queues;
2878	dev->nr_poll_queues = poll_queues;
2879	dev->nr_allocated_queues = nvme_max_io_queues(dev) + 1;
2880	dev->queues = kcalloc_node(dev->nr_allocated_queues,
2881			sizeof(struct nvme_queue), GFP_KERNEL, node);
2882	if (!dev->queues)
2883		goto out_free_dev;
2884
2885	dev->dev = get_device(&pdev->dev);
2886
2887	quirks |= check_vendor_combination_bug(pdev);
2888	if (!noacpi && acpi_storage_d3(&pdev->dev)) {
2889		/*
2890		 * Some systems use a bios work around to ask for D3 on
2891		 * platforms that support kernel managed suspend.
2892		 */
2893		dev_info(&pdev->dev,
2894			 "platform quirk: setting simple suspend\n");
2895		quirks |= NVME_QUIRK_SIMPLE_SUSPEND;
2896	}
2897	ret = nvme_init_ctrl(&dev->ctrl, &pdev->dev, &nvme_pci_ctrl_ops,
2898			     quirks);
2899	if (ret)
2900		goto out_put_device;
2901	return dev;
2902
2903out_put_device:
2904	put_device(dev->dev);
2905	kfree(dev->queues);
2906out_free_dev:
2907	kfree(dev);
2908	return ERR_PTR(ret);
2909}
2910
2911static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
2912{
2913	struct nvme_dev *dev;
2914	int result = -ENOMEM;
2915
2916	dev = nvme_pci_alloc_dev(pdev, id);
2917	if (IS_ERR(dev))
2918		return PTR_ERR(dev);
2919
2920	result = nvme_dev_map(dev);
2921	if (result)
2922		goto out_uninit_ctrl;
2923
2924	result = nvme_setup_prp_pools(dev);
2925	if (result)
2926		goto out_dev_unmap;
2927
2928	result = nvme_pci_alloc_iod_mempool(dev);
2929	if (result)
2930		goto out_release_prp_pools;
2931
2932	dev_info(dev->ctrl.device, "pci function %s\n", dev_name(&pdev->dev));
2933	pci_set_drvdata(pdev, dev);
2934
2935	nvme_reset_ctrl(&dev->ctrl);
2936	async_schedule(nvme_async_probe, dev);
2937	return 0;
2938
2939out_release_prp_pools:
2940	nvme_release_prp_pools(dev);
2941out_dev_unmap:
2942	nvme_dev_unmap(dev);
2943out_uninit_ctrl:
2944	nvme_uninit_ctrl(&dev->ctrl);
2945	return result;
2946}
2947
2948static void nvme_reset_prepare(struct pci_dev *pdev)
2949{
2950	struct nvme_dev *dev = pci_get_drvdata(pdev);
2951
2952	/*
2953	 * We don't need to check the return value from waiting for the reset
2954	 * state as pci_dev device lock is held, making it impossible to race
2955	 * with ->remove().
2956	 */
2957	nvme_disable_prepare_reset(dev, false);
2958	nvme_sync_queues(&dev->ctrl);
2959}
2960
2961static void nvme_reset_done(struct pci_dev *pdev)
2962{
2963	struct nvme_dev *dev = pci_get_drvdata(pdev);
2964
2965	if (!nvme_try_sched_reset(&dev->ctrl))
2966		flush_work(&dev->ctrl.reset_work);
2967}
2968
2969static void nvme_shutdown(struct pci_dev *pdev)
2970{
2971	struct nvme_dev *dev = pci_get_drvdata(pdev);
2972
2973	nvme_disable_prepare_reset(dev, true);
2974}
2975
2976/*
2977 * The driver's remove may be called on a device in a partially initialized
2978 * state. This function must not have any dependencies on the device state in
2979 * order to proceed.
2980 */
2981static void nvme_remove(struct pci_dev *pdev)
2982{
2983	struct nvme_dev *dev = pci_get_drvdata(pdev);
2984
2985	nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DELETING);
2986	pci_set_drvdata(pdev, NULL);
2987
2988	if (!pci_device_is_present(pdev)) {
2989		nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DEAD);
2990		nvme_dev_disable(dev, true);
2991	}
2992
2993	flush_work(&dev->ctrl.reset_work);
2994	nvme_stop_ctrl(&dev->ctrl);
2995	nvme_remove_namespaces(&dev->ctrl);
2996	nvme_dev_disable(dev, true);
2997	nvme_release_cmb(dev);
2998	nvme_free_host_mem(dev);
2999	nvme_dev_remove_admin(dev);
3000	nvme_free_queues(dev, 0);
3001	nvme_release_prp_pools(dev);
3002	nvme_dev_unmap(dev);
3003	nvme_uninit_ctrl(&dev->ctrl);
3004}
3005
3006#ifdef CONFIG_PM_SLEEP
3007static int nvme_get_power_state(struct nvme_ctrl *ctrl, u32 *ps)
3008{
3009	return nvme_get_features(ctrl, NVME_FEAT_POWER_MGMT, 0, NULL, 0, ps);
3010}
3011
3012static int nvme_set_power_state(struct nvme_ctrl *ctrl, u32 ps)
3013{
3014	return nvme_set_features(ctrl, NVME_FEAT_POWER_MGMT, ps, NULL, 0, NULL);
3015}
3016
3017static int nvme_resume(struct device *dev)
3018{
3019	struct nvme_dev *ndev = pci_get_drvdata(to_pci_dev(dev));
3020	struct nvme_ctrl *ctrl = &ndev->ctrl;
3021
3022	if (ndev->last_ps == U32_MAX ||
3023	    nvme_set_power_state(ctrl, ndev->last_ps) != 0)
3024		return nvme_try_sched_reset(&ndev->ctrl);
3025	return 0;
3026}
3027
3028static int nvme_suspend(struct device *dev)
3029{
3030	struct pci_dev *pdev = to_pci_dev(dev);
3031	struct nvme_dev *ndev = pci_get_drvdata(pdev);
3032	struct nvme_ctrl *ctrl = &ndev->ctrl;
3033	int ret = -EBUSY;
3034
3035	ndev->last_ps = U32_MAX;
3036
3037	/*
3038	 * The platform does not remove power for a kernel managed suspend so
3039	 * use host managed nvme power settings for lowest idle power if
3040	 * possible. This should have quicker resume latency than a full device
3041	 * shutdown.  But if the firmware is involved after the suspend or the
3042	 * device does not support any non-default power states, shut down the
3043	 * device fully.
3044	 *
3045	 * If ASPM is not enabled for the device, shut down the device and allow
3046	 * the PCI bus layer to put it into D3 in order to take the PCIe link
3047	 * down, so as to allow the platform to achieve its minimum low-power
3048	 * state (which may not be possible if the link is up).
3049	 *
3050	 * If a host memory buffer is enabled, shut down the device as the NVMe
3051	 * specification allows the device to access the host memory buffer in
3052	 * host DRAM from all power states, but hosts will fail access to DRAM
3053	 * during S3.
3054	 */
3055	if (pm_suspend_via_firmware() || !ctrl->npss ||
3056	    !pcie_aspm_enabled(pdev) ||
3057	    ndev->nr_host_mem_descs ||
3058	    (ndev->ctrl.quirks & NVME_QUIRK_SIMPLE_SUSPEND))
3059		return nvme_disable_prepare_reset(ndev, true);
3060
3061	nvme_start_freeze(ctrl);
3062	nvme_wait_freeze(ctrl);
3063	nvme_sync_queues(ctrl);
3064
3065	if (ctrl->state != NVME_CTRL_LIVE)
3066		goto unfreeze;
3067
3068	ret = nvme_get_power_state(ctrl, &ndev->last_ps);
3069	if (ret < 0)
3070		goto unfreeze;
3071
3072	/*
3073	 * A saved state prevents pci pm from generically controlling the
3074	 * device's power. If we're using protocol specific settings, we don't
3075	 * want pci interfering.
3076	 */
3077	pci_save_state(pdev);
3078
3079	ret = nvme_set_power_state(ctrl, ctrl->npss);
3080	if (ret < 0)
3081		goto unfreeze;
3082
3083	if (ret) {
3084		/* discard the saved state */
3085		pci_load_saved_state(pdev, NULL);
3086
3087		/*
3088		 * Clearing npss forces a controller reset on resume. The
3089		 * correct value will be rediscovered then.
3090		 */
3091		ret = nvme_disable_prepare_reset(ndev, true);
3092		ctrl->npss = 0;
3093	}
3094unfreeze:
3095	nvme_unfreeze(ctrl);
3096	return ret;
3097}
3098
3099static int nvme_simple_suspend(struct device *dev)
3100{
3101	struct nvme_dev *ndev = pci_get_drvdata(to_pci_dev(dev));
3102
3103	return nvme_disable_prepare_reset(ndev, true);
3104}
3105
3106static int nvme_simple_resume(struct device *dev)
3107{
3108	struct pci_dev *pdev = to_pci_dev(dev);
3109	struct nvme_dev *ndev = pci_get_drvdata(pdev);
3110
3111	return nvme_try_sched_reset(&ndev->ctrl);
3112}
3113
3114static const struct dev_pm_ops nvme_dev_pm_ops = {
3115	.suspend	= nvme_suspend,
3116	.resume		= nvme_resume,
3117	.freeze		= nvme_simple_suspend,
3118	.thaw		= nvme_simple_resume,
3119	.poweroff	= nvme_simple_suspend,
3120	.restore	= nvme_simple_resume,
3121};
3122#endif /* CONFIG_PM_SLEEP */
3123
3124static pci_ers_result_t nvme_error_detected(struct pci_dev *pdev,
3125						pci_channel_state_t state)
3126{
3127	struct nvme_dev *dev = pci_get_drvdata(pdev);
3128
3129	/*
3130	 * A frozen channel requires a reset. When detected, this method will
3131	 * shutdown the controller to quiesce. The controller will be restarted
3132	 * after the slot reset through driver's slot_reset callback.
3133	 */
3134	switch (state) {
3135	case pci_channel_io_normal:
3136		return PCI_ERS_RESULT_CAN_RECOVER;
3137	case pci_channel_io_frozen:
3138		dev_warn(dev->ctrl.device,
3139			"frozen state error detected, reset controller\n");
3140		nvme_dev_disable(dev, false);
3141		return PCI_ERS_RESULT_NEED_RESET;
3142	case pci_channel_io_perm_failure:
3143		dev_warn(dev->ctrl.device,
3144			"failure state error detected, request disconnect\n");
3145		return PCI_ERS_RESULT_DISCONNECT;
3146	}
3147	return PCI_ERS_RESULT_NEED_RESET;
3148}
3149
3150static pci_ers_result_t nvme_slot_reset(struct pci_dev *pdev)
3151{
3152	struct nvme_dev *dev = pci_get_drvdata(pdev);
3153
3154	dev_info(dev->ctrl.device, "restart after slot reset\n");
3155	pci_restore_state(pdev);
3156	nvme_reset_ctrl(&dev->ctrl);
3157	return PCI_ERS_RESULT_RECOVERED;
3158}
3159
3160static void nvme_error_resume(struct pci_dev *pdev)
3161{
3162	struct nvme_dev *dev = pci_get_drvdata(pdev);
3163
3164	flush_work(&dev->ctrl.reset_work);
3165}
3166
3167static const struct pci_error_handlers nvme_err_handler = {
3168	.error_detected	= nvme_error_detected,
3169	.slot_reset	= nvme_slot_reset,
3170	.resume		= nvme_error_resume,
3171	.reset_prepare	= nvme_reset_prepare,
3172	.reset_done	= nvme_reset_done,
3173};
3174
3175static const struct pci_device_id nvme_id_table[] = {
3176	{ PCI_VDEVICE(INTEL, 0x0953),	/* Intel 750/P3500/P3600/P3700 */
3177		.driver_data = NVME_QUIRK_STRIPE_SIZE |
3178				NVME_QUIRK_DEALLOCATE_ZEROES, },
3179	{ PCI_VDEVICE(INTEL, 0x0a53),	/* Intel P3520 */
3180		.driver_data = NVME_QUIRK_STRIPE_SIZE |
3181				NVME_QUIRK_DEALLOCATE_ZEROES, },
3182	{ PCI_VDEVICE(INTEL, 0x0a54),	/* Intel P4500/P4600 */
3183		.driver_data = NVME_QUIRK_STRIPE_SIZE |
3184				NVME_QUIRK_DEALLOCATE_ZEROES |
3185				NVME_QUIRK_IGNORE_DEV_SUBNQN |
3186				NVME_QUIRK_BOGUS_NID, },
3187	{ PCI_VDEVICE(INTEL, 0x0a55),	/* Dell Express Flash P4600 */
3188		.driver_data = NVME_QUIRK_STRIPE_SIZE |
3189				NVME_QUIRK_DEALLOCATE_ZEROES, },
3190	{ PCI_VDEVICE(INTEL, 0xf1a5),	/* Intel 600P/P3100 */
3191		.driver_data = NVME_QUIRK_NO_DEEPEST_PS |
3192				NVME_QUIRK_MEDIUM_PRIO_SQ |
3193				NVME_QUIRK_NO_TEMP_THRESH_CHANGE |
3194				NVME_QUIRK_DISABLE_WRITE_ZEROES, },
3195	{ PCI_VDEVICE(INTEL, 0xf1a6),	/* Intel 760p/Pro 7600p */
3196		.driver_data = NVME_QUIRK_IGNORE_DEV_SUBNQN, },
3197	{ PCI_VDEVICE(INTEL, 0x5845),	/* Qemu emulated controller */
3198		.driver_data = NVME_QUIRK_IDENTIFY_CNS |
3199				NVME_QUIRK_DISABLE_WRITE_ZEROES |
3200				NVME_QUIRK_BOGUS_NID, },
3201	{ PCI_VDEVICE(REDHAT, 0x0010),	/* Qemu emulated controller */
3202		.driver_data = NVME_QUIRK_BOGUS_NID, },
3203	{ PCI_DEVICE(0x126f, 0x2263),	/* Silicon Motion unidentified */
3204		.driver_data = NVME_QUIRK_NO_NS_DESC_LIST, },
3205	{ PCI_DEVICE(0x1bb1, 0x0100),   /* Seagate Nytro Flash Storage */
3206		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY |
3207				NVME_QUIRK_NO_NS_DESC_LIST, },
3208	{ PCI_DEVICE(0x1c58, 0x0003),	/* HGST adapter */
3209		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
3210	{ PCI_DEVICE(0x1c58, 0x0023),	/* WDC SN200 adapter */
3211		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
3212	{ PCI_DEVICE(0x1c5f, 0x0540),	/* Memblaze Pblaze4 adapter */
3213		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
3214	{ PCI_DEVICE(0x144d, 0xa821),   /* Samsung PM1725 */
3215		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
3216	{ PCI_DEVICE(0x144d, 0xa822),   /* Samsung PM1725a */
3217		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY |
3218				NVME_QUIRK_DISABLE_WRITE_ZEROES|
3219				NVME_QUIRK_IGNORE_DEV_SUBNQN, },
3220	{ PCI_DEVICE(0x1987, 0x5016),	/* Phison E16 */
3221		.driver_data = NVME_QUIRK_IGNORE_DEV_SUBNQN |
3222				NVME_QUIRK_BOGUS_NID, },
3223	{ PCI_DEVICE(0x1b4b, 0x1092),	/* Lexar 256 GB SSD */
3224		.driver_data = NVME_QUIRK_NO_NS_DESC_LIST |
3225				NVME_QUIRK_IGNORE_DEV_SUBNQN, },
3226	{ PCI_DEVICE(0x1d1d, 0x1f1f),	/* LighNVM qemu device */
3227		.driver_data = NVME_QUIRK_LIGHTNVM, },
3228	{ PCI_DEVICE(0x1d1d, 0x2807),	/* CNEX WL */
3229		.driver_data = NVME_QUIRK_LIGHTNVM, },
3230	{ PCI_DEVICE(0x1d1d, 0x2601),	/* CNEX Granby */
3231		.driver_data = NVME_QUIRK_LIGHTNVM, },
3232	{ PCI_DEVICE(0x10ec, 0x5762),   /* ADATA SX6000LNP */
3233		.driver_data = NVME_QUIRK_IGNORE_DEV_SUBNQN |
3234				NVME_QUIRK_BOGUS_NID, },
3235	{ PCI_DEVICE(0x1cc1, 0x8201),   /* ADATA SX8200PNP 512GB */
3236		.driver_data = NVME_QUIRK_NO_DEEPEST_PS |
3237				NVME_QUIRK_IGNORE_DEV_SUBNQN, },
3238	 { PCI_DEVICE(0x1344, 0x5407), /* Micron Technology Inc NVMe SSD */
3239		.driver_data = NVME_QUIRK_IGNORE_DEV_SUBNQN },
3240	 { PCI_DEVICE(0x1344, 0x6001),   /* Micron Nitro NVMe */
3241		 .driver_data = NVME_QUIRK_BOGUS_NID, },
3242	{ PCI_DEVICE(0x1c5c, 0x1504),   /* SK Hynix PC400 */
3243		.driver_data = NVME_QUIRK_DISABLE_WRITE_ZEROES, },
3244	{ PCI_DEVICE(0x15b7, 0x2001),   /*  Sandisk Skyhawk */
3245		.driver_data = NVME_QUIRK_DISABLE_WRITE_ZEROES, },
3246	{ PCI_DEVICE(0x2646, 0x2262),   /* KINGSTON SKC2000 NVMe SSD */
3247		.driver_data = NVME_QUIRK_NO_DEEPEST_PS, },
3248	{ PCI_DEVICE(0x2646, 0x2263),   /* KINGSTON A2000 NVMe SSD  */
3249		.driver_data = NVME_QUIRK_NO_DEEPEST_PS, },
3250	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2001),
3251		.driver_data = NVME_QUIRK_SINGLE_VECTOR },
3252	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2003) },
3253	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2005),
3254		.driver_data = NVME_QUIRK_SINGLE_VECTOR |
3255				NVME_QUIRK_128_BYTES_SQES |
3256				NVME_QUIRK_SHARED_TAGS |
3257				NVME_QUIRK_SKIP_CID_GEN },
3258	{ PCI_DEVICE_CLASS(PCI_CLASS_STORAGE_EXPRESS, 0xffffff) },
3259	{ 0, }
3260};
3261MODULE_DEVICE_TABLE(pci, nvme_id_table);
3262
3263static struct pci_driver nvme_driver = {
3264	.name		= "nvme",
3265	.id_table	= nvme_id_table,
3266	.probe		= nvme_probe,
3267	.remove		= nvme_remove,
3268	.shutdown	= nvme_shutdown,
3269#ifdef CONFIG_PM_SLEEP
3270	.driver		= {
3271		.pm	= &nvme_dev_pm_ops,
3272	},
3273#endif
3274	.sriov_configure = pci_sriov_configure_simple,
3275	.err_handler	= &nvme_err_handler,
3276};
3277
3278static int __init nvme_init(void)
3279{
3280	BUILD_BUG_ON(sizeof(struct nvme_create_cq) != 64);
3281	BUILD_BUG_ON(sizeof(struct nvme_create_sq) != 64);
3282	BUILD_BUG_ON(sizeof(struct nvme_delete_queue) != 64);
3283	BUILD_BUG_ON(IRQ_AFFINITY_MAX_SETS < 2);
3284
3285	return pci_register_driver(&nvme_driver);
3286}
3287
3288static void __exit nvme_exit(void)
3289{
3290	pci_unregister_driver(&nvme_driver);
3291	flush_workqueue(nvme_wq);
3292}
3293
3294MODULE_AUTHOR("Matthew Wilcox <willy@linux.intel.com>");
3295MODULE_LICENSE("GPL");
3296MODULE_VERSION("1.0");
3297module_init(nvme_init);
3298module_exit(nvme_exit);
3299