nvme-core.c revision b3b06812e199f248561ce7824a4a8a9cd573c05a
1/*
2 * NVM Express device driver
3 * Copyright (c) 2011, Intel Corporation.
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms and conditions of the GNU General Public License,
7 * version 2, as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
17 */
18
19#include <linux/nvme.h>
20#include <linux/bio.h>
21#include <linux/blkdev.h>
22#include <linux/errno.h>
23#include <linux/fs.h>
24#include <linux/genhd.h>
25#include <linux/init.h>
26#include <linux/interrupt.h>
27#include <linux/io.h>
28#include <linux/kdev_t.h>
29#include <linux/kernel.h>
30#include <linux/mm.h>
31#include <linux/module.h>
32#include <linux/moduleparam.h>
33#include <linux/pci.h>
34#include <linux/sched.h>
35#include <linux/slab.h>
36#include <linux/types.h>
37#include <linux/version.h>
38
39#define NVME_Q_DEPTH 1024
40#define SQ_SIZE(depth)		(depth * sizeof(struct nvme_command))
41#define CQ_SIZE(depth)		(depth * sizeof(struct nvme_completion))
42#define NVME_MINORS 64
43
44static int nvme_major;
45module_param(nvme_major, int, 0);
46
47/*
48 * Represents an NVM Express device.  Each nvme_dev is a PCI function.
49 */
50struct nvme_dev {
51	struct list_head node;
52	struct nvme_queue **queues;
53	u32 __iomem *dbs;
54	struct pci_dev *pci_dev;
55	int instance;
56	int queue_count;
57	u32 ctrl_config;
58	struct msix_entry *entry;
59	struct nvme_bar __iomem *bar;
60	struct list_head namespaces;
61};
62
63/*
64 * An NVM Express namespace is equivalent to a SCSI LUN
65 */
66struct nvme_ns {
67	struct list_head list;
68
69	struct nvme_dev *dev;
70	struct request_queue *queue;
71	struct gendisk *disk;
72
73	int ns_id;
74	int lba_shift;
75};
76
77/*
78 * An NVM Express queue.  Each device has at least two (one for admin
79 * commands and one for I/O commands).
80 */
81struct nvme_queue {
82	struct device *q_dmadev;
83	spinlock_t q_lock;
84	struct nvme_command *sq_cmds;
85	volatile struct nvme_completion *cqes;
86	dma_addr_t sq_dma_addr;
87	dma_addr_t cq_dma_addr;
88	wait_queue_head_t sq_full;
89	struct bio_list sq_cong;
90	u32 __iomem *q_db;
91	u16 q_depth;
92	u16 cq_vector;
93	u16 sq_head;
94	u16 sq_tail;
95	u16 cq_head;
96	u16 cq_cycle;
97	unsigned long cmdid_data[];
98};
99
100/*
101 * Check we didin't inadvertently grow the command struct
102 */
103static inline void _nvme_check_size(void)
104{
105	BUILD_BUG_ON(sizeof(struct nvme_rw_command) != 64);
106	BUILD_BUG_ON(sizeof(struct nvme_create_cq) != 64);
107	BUILD_BUG_ON(sizeof(struct nvme_create_sq) != 64);
108	BUILD_BUG_ON(sizeof(struct nvme_delete_queue) != 64);
109	BUILD_BUG_ON(sizeof(struct nvme_features) != 64);
110	BUILD_BUG_ON(sizeof(struct nvme_command) != 64);
111	BUILD_BUG_ON(sizeof(struct nvme_id_ctrl) != 4096);
112	BUILD_BUG_ON(sizeof(struct nvme_id_ns) != 4096);
113	BUILD_BUG_ON(sizeof(struct nvme_lba_range_type) != 64);
114}
115
116/**
117 * alloc_cmdid - Allocate a Command ID
118 * @param nvmeq The queue that will be used for this command
119 * @param ctx A pointer that will be passed to the handler
120 * @param handler The ID of the handler to call
121 *
122 * Allocate a Command ID for a queue.  The data passed in will
123 * be passed to the completion handler.  This is implemented by using
124 * the bottom two bits of the ctx pointer to store the handler ID.
125 * Passing in a pointer that's not 4-byte aligned will cause a BUG.
126 * We can change this if it becomes a problem.
127 */
128static int alloc_cmdid(struct nvme_queue *nvmeq, void *ctx, int handler)
129{
130	int depth = nvmeq->q_depth;
131	unsigned long data = (unsigned long)ctx | handler;
132	int cmdid;
133
134	BUG_ON((unsigned long)ctx & 3);
135
136	do {
137		cmdid = find_first_zero_bit(nvmeq->cmdid_data, depth);
138		if (cmdid >= depth)
139			return -EBUSY;
140	} while (test_and_set_bit(cmdid, nvmeq->cmdid_data));
141
142	nvmeq->cmdid_data[cmdid + BITS_TO_LONGS(depth)] = data;
143	return cmdid;
144}
145
146static int alloc_cmdid_killable(struct nvme_queue *nvmeq, void *ctx,
147								int handler)
148{
149	int cmdid;
150	wait_event_killable(nvmeq->sq_full,
151			(cmdid = alloc_cmdid(nvmeq, ctx, handler)) >= 0);
152	return (cmdid < 0) ? -EINTR : cmdid;
153}
154
155/* If you need more than four handlers, you'll need to change how
156 * alloc_cmdid and nvme_process_cq work
157 */
158enum {
159	sync_completion_id = 0,
160	bio_completion_id,
161};
162
163static unsigned long free_cmdid(struct nvme_queue *nvmeq, int cmdid)
164{
165	unsigned long data;
166
167	data = nvmeq->cmdid_data[cmdid + BITS_TO_LONGS(nvmeq->q_depth)];
168	clear_bit(cmdid, nvmeq->cmdid_data);
169	wake_up(&nvmeq->sq_full);
170	return data;
171}
172
173static struct nvme_queue *get_nvmeq(struct nvme_ns *ns)
174{
175	return ns->dev->queues[1];
176}
177
178static void put_nvmeq(struct nvme_queue *nvmeq)
179{
180}
181
182/**
183 * nvme_submit_cmd: Copy a command into a queue and ring the doorbell
184 * @nvmeq: The queue to use
185 * @cmd: The command to send
186 *
187 * Safe to use from interrupt context
188 */
189static int nvme_submit_cmd(struct nvme_queue *nvmeq, struct nvme_command *cmd)
190{
191	unsigned long flags;
192	u16 tail;
193	/* XXX: Need to check tail isn't going to overrun head */
194	spin_lock_irqsave(&nvmeq->q_lock, flags);
195	tail = nvmeq->sq_tail;
196	memcpy(&nvmeq->sq_cmds[tail], cmd, sizeof(*cmd));
197	writel(tail, nvmeq->q_db);
198	if (++tail == nvmeq->q_depth)
199		tail = 0;
200	nvmeq->sq_tail = tail;
201	spin_unlock_irqrestore(&nvmeq->q_lock, flags);
202
203	return 0;
204}
205
206struct nvme_req_info {
207	struct bio *bio;
208	int nents;
209	struct scatterlist sg[0];
210};
211
212/* XXX: use a mempool */
213static struct nvme_req_info *alloc_info(unsigned nseg, gfp_t gfp)
214{
215	return kmalloc(sizeof(struct nvme_req_info) +
216			sizeof(struct scatterlist) * nseg, gfp);
217}
218
219static void free_info(struct nvme_req_info *info)
220{
221	kfree(info);
222}
223
224static void bio_completion(struct nvme_queue *nvmeq, void *ctx,
225						struct nvme_completion *cqe)
226{
227	struct nvme_req_info *info = ctx;
228	struct bio *bio = info->bio;
229	u16 status = le16_to_cpup(&cqe->status) >> 1;
230
231	dma_unmap_sg(nvmeq->q_dmadev, info->sg, info->nents,
232			bio_data_dir(bio) ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
233	free_info(info);
234	bio_endio(bio, status ? -EIO : 0);
235}
236
237static int nvme_map_bio(struct device *dev, struct nvme_req_info *info,
238		struct bio *bio, enum dma_data_direction dma_dir, int psegs)
239{
240	struct bio_vec *bvec;
241	struct scatterlist *sg = info->sg;
242	int i, nsegs;
243
244	sg_init_table(sg, psegs);
245	bio_for_each_segment(bvec, bio, i) {
246		sg_set_page(sg, bvec->bv_page, bvec->bv_len, bvec->bv_offset);
247		/* XXX: handle non-mergable here */
248		nsegs++;
249	}
250	info->nents = nsegs;
251
252	return dma_map_sg(dev, info->sg, info->nents, dma_dir);
253}
254
255static int nvme_submit_bio_queue(struct nvme_queue *nvmeq, struct nvme_ns *ns,
256								struct bio *bio)
257{
258	struct nvme_rw_command *cmnd;
259	struct nvme_req_info *info;
260	enum dma_data_direction dma_dir;
261	int cmdid;
262	u16 control;
263	u32 dsmgmt;
264	unsigned long flags;
265	int psegs = bio_phys_segments(ns->queue, bio);
266
267	info = alloc_info(psegs, GFP_NOIO);
268	if (!info)
269		goto congestion;
270	info->bio = bio;
271
272	cmdid = alloc_cmdid(nvmeq, info, bio_completion_id);
273	if (unlikely(cmdid < 0))
274		goto free_info;
275
276	control = 0;
277	if (bio->bi_rw & REQ_FUA)
278		control |= NVME_RW_FUA;
279	if (bio->bi_rw & (REQ_FAILFAST_DEV | REQ_RAHEAD))
280		control |= NVME_RW_LR;
281
282	dsmgmt = 0;
283	if (bio->bi_rw & REQ_RAHEAD)
284		dsmgmt |= NVME_RW_DSM_FREQ_PREFETCH;
285
286	spin_lock_irqsave(&nvmeq->q_lock, flags);
287	cmnd = &nvmeq->sq_cmds[nvmeq->sq_tail].rw;
288
289	if (bio_data_dir(bio)) {
290		cmnd->opcode = nvme_cmd_write;
291		dma_dir = DMA_TO_DEVICE;
292	} else {
293		cmnd->opcode = nvme_cmd_read;
294		dma_dir = DMA_FROM_DEVICE;
295	}
296
297	nvme_map_bio(nvmeq->q_dmadev, info, bio, dma_dir, psegs);
298
299	cmnd->flags = 1;
300	cmnd->command_id = cmdid;
301	cmnd->nsid = cpu_to_le32(ns->ns_id);
302	cmnd->prp1 = cpu_to_le64(sg_phys(info->sg));
303	/* XXX: Support more than one PRP */
304	cmnd->slba = cpu_to_le64(bio->bi_sector >> (ns->lba_shift - 9));
305	cmnd->length = cpu_to_le16((bio->bi_size >> ns->lba_shift) - 1);
306	cmnd->control = cpu_to_le16(control);
307	cmnd->dsmgmt = cpu_to_le32(dsmgmt);
308
309	writel(nvmeq->sq_tail, nvmeq->q_db);
310	if (++nvmeq->sq_tail == nvmeq->q_depth)
311		nvmeq->sq_tail = 0;
312
313	spin_unlock_irqrestore(&nvmeq->q_lock, flags);
314
315	return 0;
316
317 free_info:
318	free_info(info);
319 congestion:
320	return -EBUSY;
321}
322
323/*
324 * NB: return value of non-zero would mean that we were a stacking driver.
325 * make_request must always succeed.
326 */
327static int nvme_make_request(struct request_queue *q, struct bio *bio)
328{
329	struct nvme_ns *ns = q->queuedata;
330	struct nvme_queue *nvmeq = get_nvmeq(ns);
331
332	if (nvme_submit_bio_queue(nvmeq, ns, bio)) {
333		blk_set_queue_congested(q, rw_is_sync(bio->bi_rw));
334		bio_list_add(&nvmeq->sq_cong, bio);
335	}
336	put_nvmeq(nvmeq);
337
338	return 0;
339}
340
341struct sync_cmd_info {
342	struct task_struct *task;
343	u32 result;
344	int status;
345};
346
347static void sync_completion(struct nvme_queue *nvmeq, void *ctx,
348						struct nvme_completion *cqe)
349{
350	struct sync_cmd_info *cmdinfo = ctx;
351	cmdinfo->result = le32_to_cpup(&cqe->result);
352	cmdinfo->status = le16_to_cpup(&cqe->status) >> 1;
353	wake_up_process(cmdinfo->task);
354}
355
356typedef void (*completion_fn)(struct nvme_queue *, void *,
357						struct nvme_completion *);
358
359static irqreturn_t nvme_process_cq(struct nvme_queue *nvmeq)
360{
361	u16 head, cycle;
362
363	static const completion_fn completions[4] = {
364		[sync_completion_id] = sync_completion,
365		[bio_completion_id]  = bio_completion,
366	};
367
368	head = nvmeq->cq_head;
369	cycle = nvmeq->cq_cycle;
370
371	for (;;) {
372		unsigned long data;
373		void *ptr;
374		unsigned char handler;
375		struct nvme_completion cqe = nvmeq->cqes[head];
376		if ((le16_to_cpu(cqe.status) & 1) != cycle)
377			break;
378		nvmeq->sq_head = le16_to_cpu(cqe.sq_head);
379		if (++head == nvmeq->q_depth) {
380			head = 0;
381			cycle = !cycle;
382		}
383
384		data = free_cmdid(nvmeq, cqe.command_id);
385		handler = data & 3;
386		ptr = (void *)(data & ~3UL);
387		completions[handler](nvmeq, ptr, &cqe);
388	}
389
390	/* If the controller ignores the cq head doorbell and continuously
391	 * writes to the queue, it is theoretically possible to wrap around
392	 * the queue twice and mistakenly return IRQ_NONE.  Linux only
393	 * requires that 0.1% of your interrupts are handled, so this isn't
394	 * a big problem.
395	 */
396	if (head == nvmeq->cq_head && cycle == nvmeq->cq_cycle)
397		return IRQ_NONE;
398
399	writel(head, nvmeq->q_db + 1);
400	nvmeq->cq_head = head;
401	nvmeq->cq_cycle = cycle;
402
403	return IRQ_HANDLED;
404}
405
406static irqreturn_t nvme_irq(int irq, void *data)
407{
408	return nvme_process_cq(data);
409}
410
411/*
412 * Returns 0 on success.  If the result is negative, it's a Linux error code;
413 * if the result is positive, it's an NVM Express status code
414 */
415static int nvme_submit_sync_cmd(struct nvme_queue *q, struct nvme_command *cmd,
416								u32 *result)
417{
418	int cmdid;
419	struct sync_cmd_info cmdinfo;
420
421	cmdinfo.task = current;
422	cmdinfo.status = -EINTR;
423
424	cmdid = alloc_cmdid_killable(q, &cmdinfo, sync_completion_id);
425	if (cmdid < 0)
426		return cmdid;
427	cmd->common.command_id = cmdid;
428
429	set_current_state(TASK_UNINTERRUPTIBLE);
430	nvme_submit_cmd(q, cmd);
431	schedule();
432
433	if (result)
434		*result = cmdinfo.result;
435
436	return cmdinfo.status;
437}
438
439static int nvme_submit_admin_cmd(struct nvme_dev *dev, struct nvme_command *cmd,
440								u32 *result)
441{
442	return nvme_submit_sync_cmd(dev->queues[0], cmd, result);
443}
444
445static int adapter_delete_queue(struct nvme_dev *dev, u8 opcode, u16 id)
446{
447	int status;
448	struct nvme_command c;
449
450	memset(&c, 0, sizeof(c));
451	c.delete_queue.opcode = opcode;
452	c.delete_queue.qid = cpu_to_le16(id);
453
454	status = nvme_submit_admin_cmd(dev, &c, NULL);
455	if (status)
456		return -EIO;
457	return 0;
458}
459
460static int adapter_alloc_cq(struct nvme_dev *dev, u16 qid,
461						struct nvme_queue *nvmeq)
462{
463	int status;
464	struct nvme_command c;
465	int flags = NVME_QUEUE_PHYS_CONTIG | NVME_CQ_IRQ_ENABLED;
466
467	memset(&c, 0, sizeof(c));
468	c.create_cq.opcode = nvme_admin_create_cq;
469	c.create_cq.prp1 = cpu_to_le64(nvmeq->cq_dma_addr);
470	c.create_cq.cqid = cpu_to_le16(qid);
471	c.create_cq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
472	c.create_cq.cq_flags = cpu_to_le16(flags);
473	c.create_cq.irq_vector = cpu_to_le16(nvmeq->cq_vector);
474
475	status = nvme_submit_admin_cmd(dev, &c, NULL);
476	if (status)
477		return -EIO;
478	return 0;
479}
480
481static int adapter_alloc_sq(struct nvme_dev *dev, u16 qid,
482						struct nvme_queue *nvmeq)
483{
484	int status;
485	struct nvme_command c;
486	int flags = NVME_QUEUE_PHYS_CONTIG | NVME_SQ_PRIO_MEDIUM;
487
488	memset(&c, 0, sizeof(c));
489	c.create_sq.opcode = nvme_admin_create_sq;
490	c.create_sq.prp1 = cpu_to_le64(nvmeq->sq_dma_addr);
491	c.create_sq.sqid = cpu_to_le16(qid);
492	c.create_sq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
493	c.create_sq.sq_flags = cpu_to_le16(flags);
494	c.create_sq.cqid = cpu_to_le16(qid);
495
496	status = nvme_submit_admin_cmd(dev, &c, NULL);
497	if (status)
498		return -EIO;
499	return 0;
500}
501
502static int adapter_delete_cq(struct nvme_dev *dev, u16 cqid)
503{
504	return adapter_delete_queue(dev, nvme_admin_delete_cq, cqid);
505}
506
507static int adapter_delete_sq(struct nvme_dev *dev, u16 sqid)
508{
509	return adapter_delete_queue(dev, nvme_admin_delete_sq, sqid);
510}
511
512static void nvme_free_queue(struct nvme_dev *dev, int qid)
513{
514	struct nvme_queue *nvmeq = dev->queues[qid];
515
516	free_irq(dev->entry[nvmeq->cq_vector].vector, nvmeq);
517
518	/* Don't tell the adapter to delete the admin queue */
519	if (qid) {
520		adapter_delete_sq(dev, qid);
521		adapter_delete_cq(dev, qid);
522	}
523
524	dma_free_coherent(nvmeq->q_dmadev, CQ_SIZE(nvmeq->q_depth),
525				(void *)nvmeq->cqes, nvmeq->cq_dma_addr);
526	dma_free_coherent(nvmeq->q_dmadev, SQ_SIZE(nvmeq->q_depth),
527					nvmeq->sq_cmds, nvmeq->sq_dma_addr);
528	kfree(nvmeq);
529}
530
531static struct nvme_queue *nvme_alloc_queue(struct nvme_dev *dev, int qid,
532							int depth, int vector)
533{
534	struct device *dmadev = &dev->pci_dev->dev;
535	unsigned extra = (depth + BITS_TO_LONGS(depth)) * sizeof(long);
536	struct nvme_queue *nvmeq = kzalloc(sizeof(*nvmeq) + extra, GFP_KERNEL);
537	if (!nvmeq)
538		return NULL;
539
540	nvmeq->cqes = dma_alloc_coherent(dmadev, CQ_SIZE(depth),
541					&nvmeq->cq_dma_addr, GFP_KERNEL);
542	if (!nvmeq->cqes)
543		goto free_nvmeq;
544	memset((void *)nvmeq->cqes, 0, CQ_SIZE(depth));
545
546	nvmeq->sq_cmds = dma_alloc_coherent(dmadev, SQ_SIZE(depth),
547					&nvmeq->sq_dma_addr, GFP_KERNEL);
548	if (!nvmeq->sq_cmds)
549		goto free_cqdma;
550
551	nvmeq->q_dmadev = dmadev;
552	spin_lock_init(&nvmeq->q_lock);
553	nvmeq->cq_head = 0;
554	nvmeq->cq_cycle = 1;
555	init_waitqueue_head(&nvmeq->sq_full);
556	bio_list_init(&nvmeq->sq_cong);
557	nvmeq->q_db = &dev->dbs[qid * 2];
558	nvmeq->q_depth = depth;
559	nvmeq->cq_vector = vector;
560
561	return nvmeq;
562
563 free_cqdma:
564	dma_free_coherent(dmadev, CQ_SIZE(nvmeq->q_depth), (void *)nvmeq->cqes,
565							nvmeq->cq_dma_addr);
566 free_nvmeq:
567	kfree(nvmeq);
568	return NULL;
569}
570
571static int queue_request_irq(struct nvme_dev *dev, struct nvme_queue *nvmeq,
572							const char *name)
573{
574	return request_irq(dev->entry[nvmeq->cq_vector].vector, nvme_irq,
575				IRQF_DISABLED | IRQF_SHARED, name, nvmeq);
576}
577
578static __devinit struct nvme_queue *nvme_create_queue(struct nvme_dev *dev,
579					int qid, int cq_size, int vector)
580{
581	int result;
582	struct nvme_queue *nvmeq = nvme_alloc_queue(dev, qid, cq_size, vector);
583
584	result = adapter_alloc_cq(dev, qid, nvmeq);
585	if (result < 0)
586		goto free_nvmeq;
587
588	result = adapter_alloc_sq(dev, qid, nvmeq);
589	if (result < 0)
590		goto release_cq;
591
592	result = queue_request_irq(dev, nvmeq, "nvme");
593	if (result < 0)
594		goto release_sq;
595
596	return nvmeq;
597
598 release_sq:
599	adapter_delete_sq(dev, qid);
600 release_cq:
601	adapter_delete_cq(dev, qid);
602 free_nvmeq:
603	dma_free_coherent(nvmeq->q_dmadev, CQ_SIZE(nvmeq->q_depth),
604				(void *)nvmeq->cqes, nvmeq->cq_dma_addr);
605	dma_free_coherent(nvmeq->q_dmadev, SQ_SIZE(nvmeq->q_depth),
606					nvmeq->sq_cmds, nvmeq->sq_dma_addr);
607	kfree(nvmeq);
608	return NULL;
609}
610
611static int __devinit nvme_configure_admin_queue(struct nvme_dev *dev)
612{
613	int result;
614	u32 aqa;
615	struct nvme_queue *nvmeq;
616
617	dev->dbs = ((void __iomem *)dev->bar) + 4096;
618
619	nvmeq = nvme_alloc_queue(dev, 0, 64, 0);
620
621	aqa = nvmeq->q_depth - 1;
622	aqa |= aqa << 16;
623
624	dev->ctrl_config = NVME_CC_ENABLE | NVME_CC_CSS_NVM;
625	dev->ctrl_config |= (PAGE_SHIFT - 12) << NVME_CC_MPS_SHIFT;
626	dev->ctrl_config |= NVME_CC_ARB_RR | NVME_CC_SHN_NONE;
627
628	writel(aqa, &dev->bar->aqa);
629	writeq(nvmeq->sq_dma_addr, &dev->bar->asq);
630	writeq(nvmeq->cq_dma_addr, &dev->bar->acq);
631	writel(dev->ctrl_config, &dev->bar->cc);
632
633	while (!(readl(&dev->bar->csts) & NVME_CSTS_RDY)) {
634		msleep(100);
635		if (fatal_signal_pending(current))
636			return -EINTR;
637	}
638
639	result = queue_request_irq(dev, nvmeq, "nvme admin");
640	dev->queues[0] = nvmeq;
641	return result;
642}
643
644static int nvme_identify(struct nvme_ns *ns, void __user *addr, int cns)
645{
646	struct nvme_dev *dev = ns->dev;
647	int status;
648	struct nvme_command c;
649	void *page;
650	dma_addr_t dma_addr;
651
652	page = dma_alloc_coherent(&dev->pci_dev->dev, 4096, &dma_addr,
653								GFP_KERNEL);
654
655	memset(&c, 0, sizeof(c));
656	c.identify.opcode = nvme_admin_identify;
657	c.identify.nsid = cns ? 0 : cpu_to_le32(ns->ns_id);
658	c.identify.prp1 = cpu_to_le64(dma_addr);
659	c.identify.cns = cpu_to_le32(cns);
660
661	status = nvme_submit_admin_cmd(dev, &c, NULL);
662
663	if (status)
664		status = -EIO;
665	else if (copy_to_user(addr, page, 4096))
666		status = -EFAULT;
667
668	dma_free_coherent(&dev->pci_dev->dev, 4096, page, dma_addr);
669
670	return status;
671}
672
673static int nvme_get_range_type(struct nvme_ns *ns, void __user *addr)
674{
675	struct nvme_dev *dev = ns->dev;
676	int status;
677	struct nvme_command c;
678	void *page;
679	dma_addr_t dma_addr;
680
681	page = dma_alloc_coherent(&dev->pci_dev->dev, 4096, &dma_addr,
682								GFP_KERNEL);
683
684	memset(&c, 0, sizeof(c));
685	c.features.opcode = nvme_admin_get_features;
686	c.features.nsid = cpu_to_le32(ns->ns_id);
687	c.features.prp1 = cpu_to_le64(dma_addr);
688	c.features.fid = cpu_to_le32(NVME_FEAT_LBA_RANGE);
689
690	status = nvme_submit_admin_cmd(dev, &c, NULL);
691
692	/* XXX: Assuming first range for now */
693	if (status)
694		status = -EIO;
695	else if (copy_to_user(addr, page, 64))
696		status = -EFAULT;
697
698	dma_free_coherent(&dev->pci_dev->dev, 4096, page, dma_addr);
699
700	return status;
701}
702
703static int nvme_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd,
704							unsigned long arg)
705{
706	struct nvme_ns *ns = bdev->bd_disk->private_data;
707
708	switch (cmd) {
709	case NVME_IOCTL_IDENTIFY_NS:
710		return nvme_identify(ns, (void __user *)arg, 0);
711	case NVME_IOCTL_IDENTIFY_CTRL:
712		return nvme_identify(ns, (void __user *)arg, 1);
713	case NVME_IOCTL_GET_RANGE_TYPE:
714		return nvme_get_range_type(ns, (void __user *)arg);
715	default:
716		return -ENOTTY;
717	}
718}
719
720static const struct block_device_operations nvme_fops = {
721	.owner		= THIS_MODULE,
722	.ioctl		= nvme_ioctl,
723};
724
725static struct nvme_ns *nvme_alloc_ns(struct nvme_dev *dev, int index,
726			struct nvme_id_ns *id, struct nvme_lba_range_type *rt)
727{
728	struct nvme_ns *ns;
729	struct gendisk *disk;
730	int lbaf;
731
732	if (rt->attributes & NVME_LBART_ATTRIB_HIDE)
733		return NULL;
734
735	ns = kzalloc(sizeof(*ns), GFP_KERNEL);
736	if (!ns)
737		return NULL;
738	ns->queue = blk_alloc_queue(GFP_KERNEL);
739	if (!ns->queue)
740		goto out_free_ns;
741	ns->queue->queue_flags = QUEUE_FLAG_DEFAULT | QUEUE_FLAG_NOMERGES |
742				QUEUE_FLAG_NONROT | QUEUE_FLAG_DISCARD;
743	blk_queue_make_request(ns->queue, nvme_make_request);
744	ns->dev = dev;
745	ns->queue->queuedata = ns;
746
747	disk = alloc_disk(NVME_MINORS);
748	if (!disk)
749		goto out_free_queue;
750	ns->ns_id = index;
751	ns->disk = disk;
752	lbaf = id->flbas & 0xf;
753	ns->lba_shift = id->lbaf[lbaf].ds;
754
755	disk->major = nvme_major;
756	disk->minors = NVME_MINORS;
757	disk->first_minor = NVME_MINORS * index;
758	disk->fops = &nvme_fops;
759	disk->private_data = ns;
760	disk->queue = ns->queue;
761	sprintf(disk->disk_name, "nvme%dn%d", dev->instance, index);
762	set_capacity(disk, le64_to_cpup(&id->nsze) << (ns->lba_shift - 9));
763
764	return ns;
765
766 out_free_queue:
767	blk_cleanup_queue(ns->queue);
768 out_free_ns:
769	kfree(ns);
770	return NULL;
771}
772
773static void nvme_ns_free(struct nvme_ns *ns)
774{
775	put_disk(ns->disk);
776	blk_cleanup_queue(ns->queue);
777	kfree(ns);
778}
779
780static int set_queue_count(struct nvme_dev *dev, int count)
781{
782	int status;
783	u32 result;
784	struct nvme_command c;
785	u32 q_count = (count - 1) | ((count - 1) << 16);
786
787	memset(&c, 0, sizeof(c));
788	c.features.opcode = nvme_admin_get_features;
789	c.features.fid = cpu_to_le32(NVME_FEAT_NUM_QUEUES);
790	c.features.dword11 = cpu_to_le32(q_count);
791
792	status = nvme_submit_admin_cmd(dev, &c, &result);
793	if (status)
794		return -EIO;
795	return min(result & 0xffff, result >> 16) + 1;
796}
797
798/* XXX: Create per-CPU queues */
799static int __devinit nvme_setup_io_queues(struct nvme_dev *dev)
800{
801	int this_cpu;
802
803	set_queue_count(dev, 1);
804
805	this_cpu = get_cpu();
806	dev->queues[1] = nvme_create_queue(dev, 1, NVME_Q_DEPTH, this_cpu);
807	put_cpu();
808	if (!dev->queues[1])
809		return -ENOMEM;
810	dev->queue_count++;
811
812	return 0;
813}
814
815static void nvme_free_queues(struct nvme_dev *dev)
816{
817	int i;
818
819	for (i = dev->queue_count - 1; i >= 0; i--)
820		nvme_free_queue(dev, i);
821}
822
823static int __devinit nvme_dev_add(struct nvme_dev *dev)
824{
825	int res, nn, i;
826	struct nvme_ns *ns, *next;
827	void *id;
828	dma_addr_t dma_addr;
829	struct nvme_command cid, crt;
830
831	res = nvme_setup_io_queues(dev);
832	if (res)
833		return res;
834
835	/* XXX: Switch to a SG list once prp2 works */
836	id = dma_alloc_coherent(&dev->pci_dev->dev, 8192, &dma_addr,
837								GFP_KERNEL);
838
839	memset(&cid, 0, sizeof(cid));
840	cid.identify.opcode = nvme_admin_identify;
841	cid.identify.nsid = 0;
842	cid.identify.prp1 = cpu_to_le64(dma_addr);
843	cid.identify.cns = cpu_to_le32(1);
844
845	res = nvme_submit_admin_cmd(dev, &cid, NULL);
846	if (res) {
847		res = -EIO;
848		goto out_free;
849	}
850
851	nn = le32_to_cpup(&((struct nvme_id_ctrl *)id)->nn);
852
853	cid.identify.cns = 0;
854	memset(&crt, 0, sizeof(crt));
855	crt.features.opcode = nvme_admin_get_features;
856	crt.features.prp1 = cpu_to_le64(dma_addr + 4096);
857	crt.features.fid = cpu_to_le32(NVME_FEAT_LBA_RANGE);
858
859	for (i = 0; i < nn; i++) {
860		cid.identify.nsid = cpu_to_le32(i);
861		res = nvme_submit_admin_cmd(dev, &cid, NULL);
862		if (res)
863			continue;
864
865		if (((struct nvme_id_ns *)id)->ncap == 0)
866			continue;
867
868		crt.features.nsid = cpu_to_le32(i);
869		res = nvme_submit_admin_cmd(dev, &crt, NULL);
870		if (res)
871			continue;
872
873		ns = nvme_alloc_ns(dev, i, id, id + 4096);
874		if (ns)
875			list_add_tail(&ns->list, &dev->namespaces);
876	}
877	list_for_each_entry(ns, &dev->namespaces, list)
878		add_disk(ns->disk);
879
880	dma_free_coherent(&dev->pci_dev->dev, 4096, id, dma_addr);
881	return 0;
882
883 out_free:
884	list_for_each_entry_safe(ns, next, &dev->namespaces, list) {
885		list_del(&ns->list);
886		nvme_ns_free(ns);
887	}
888
889	dma_free_coherent(&dev->pci_dev->dev, 4096, id, dma_addr);
890	return res;
891}
892
893static int nvme_dev_remove(struct nvme_dev *dev)
894{
895	struct nvme_ns *ns, *next;
896
897	/* TODO: wait all I/O finished or cancel them */
898
899	list_for_each_entry_safe(ns, next, &dev->namespaces, list) {
900		list_del(&ns->list);
901		del_gendisk(ns->disk);
902		nvme_ns_free(ns);
903	}
904
905	nvme_free_queues(dev);
906
907	return 0;
908}
909
910/* XXX: Use an ida or something to let remove / add work correctly */
911static void nvme_set_instance(struct nvme_dev *dev)
912{
913	static int instance;
914	dev->instance = instance++;
915}
916
917static void nvme_release_instance(struct nvme_dev *dev)
918{
919}
920
921static int __devinit nvme_probe(struct pci_dev *pdev,
922						const struct pci_device_id *id)
923{
924	int result = -ENOMEM;
925	struct nvme_dev *dev;
926
927	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
928	if (!dev)
929		return -ENOMEM;
930	dev->entry = kcalloc(num_possible_cpus(), sizeof(*dev->entry),
931								GFP_KERNEL);
932	if (!dev->entry)
933		goto free;
934	dev->queues = kcalloc(2, sizeof(void *), GFP_KERNEL);
935	if (!dev->queues)
936		goto free;
937
938	INIT_LIST_HEAD(&dev->namespaces);
939	dev->pci_dev = pdev;
940	pci_set_drvdata(pdev, dev);
941	dma_set_mask(&dev->pci_dev->dev, DMA_BIT_MASK(64));
942	nvme_set_instance(dev);
943
944	dev->bar = ioremap(pci_resource_start(pdev, 0), 8192);
945	if (!dev->bar) {
946		result = -ENOMEM;
947		goto disable;
948	}
949
950	result = nvme_configure_admin_queue(dev);
951	if (result)
952		goto unmap;
953	dev->queue_count++;
954
955	result = nvme_dev_add(dev);
956	if (result)
957		goto delete;
958	return 0;
959
960 delete:
961	nvme_free_queues(dev);
962 unmap:
963	iounmap(dev->bar);
964 disable:
965	pci_disable_msix(pdev);
966	nvme_release_instance(dev);
967 free:
968	kfree(dev->queues);
969	kfree(dev->entry);
970	kfree(dev);
971	return result;
972}
973
974static void __devexit nvme_remove(struct pci_dev *pdev)
975{
976	struct nvme_dev *dev = pci_get_drvdata(pdev);
977	nvme_dev_remove(dev);
978	pci_disable_msix(pdev);
979	iounmap(dev->bar);
980	nvme_release_instance(dev);
981	kfree(dev->queues);
982	kfree(dev->entry);
983	kfree(dev);
984}
985
986/* These functions are yet to be implemented */
987#define nvme_error_detected NULL
988#define nvme_dump_registers NULL
989#define nvme_link_reset NULL
990#define nvme_slot_reset NULL
991#define nvme_error_resume NULL
992#define nvme_suspend NULL
993#define nvme_resume NULL
994
995static struct pci_error_handlers nvme_err_handler = {
996	.error_detected	= nvme_error_detected,
997	.mmio_enabled	= nvme_dump_registers,
998	.link_reset	= nvme_link_reset,
999	.slot_reset	= nvme_slot_reset,
1000	.resume		= nvme_error_resume,
1001};
1002
1003/* Move to pci_ids.h later */
1004#define PCI_CLASS_STORAGE_EXPRESS	0x010802
1005
1006static DEFINE_PCI_DEVICE_TABLE(nvme_id_table) = {
1007	{ PCI_DEVICE_CLASS(PCI_CLASS_STORAGE_EXPRESS, 0xffffff) },
1008	{ 0, }
1009};
1010MODULE_DEVICE_TABLE(pci, nvme_id_table);
1011
1012static struct pci_driver nvme_driver = {
1013	.name		= "nvme",
1014	.id_table	= nvme_id_table,
1015	.probe		= nvme_probe,
1016	.remove		= __devexit_p(nvme_remove),
1017	.suspend	= nvme_suspend,
1018	.resume		= nvme_resume,
1019	.err_handler	= &nvme_err_handler,
1020};
1021
1022static int __init nvme_init(void)
1023{
1024	int result;
1025
1026	nvme_major = register_blkdev(nvme_major, "nvme");
1027	if (nvme_major <= 0)
1028		return -EBUSY;
1029
1030	result = pci_register_driver(&nvme_driver);
1031	if (!result)
1032		return 0;
1033
1034	unregister_blkdev(nvme_major, "nvme");
1035	return result;
1036}
1037
1038static void __exit nvme_exit(void)
1039{
1040	pci_unregister_driver(&nvme_driver);
1041	unregister_blkdev(nvme_major, "nvme");
1042}
1043
1044MODULE_AUTHOR("Matthew Wilcox <willy@linux.intel.com>");
1045MODULE_LICENSE("GPL");
1046MODULE_VERSION("0.1");
1047module_init(nvme_init);
1048module_exit(nvme_exit);
1049