x86, mce: Fix sparse errors
[cascardo/linux.git] / drivers / block / nvme-core.c
1 /*
2  * NVM Express device driver
3  * Copyright (c) 2011-2014, Intel Corporation.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms and conditions of the GNU General Public License,
7  * version 2, as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  */
14
15 #include <linux/nvme.h>
16 #include <linux/bitops.h>
17 #include <linux/blkdev.h>
18 #include <linux/blk-mq.h>
19 #include <linux/cpu.h>
20 #include <linux/delay.h>
21 #include <linux/errno.h>
22 #include <linux/fs.h>
23 #include <linux/genhd.h>
24 #include <linux/hdreg.h>
25 #include <linux/idr.h>
26 #include <linux/init.h>
27 #include <linux/interrupt.h>
28 #include <linux/io.h>
29 #include <linux/kdev_t.h>
30 #include <linux/kthread.h>
31 #include <linux/kernel.h>
32 #include <linux/mm.h>
33 #include <linux/module.h>
34 #include <linux/moduleparam.h>
35 #include <linux/pci.h>
36 #include <linux/poison.h>
37 #include <linux/ptrace.h>
38 #include <linux/sched.h>
39 #include <linux/slab.h>
40 #include <linux/types.h>
41 #include <scsi/sg.h>
42 #include <asm-generic/io-64-nonatomic-lo-hi.h>
43
44 #define NVME_Q_DEPTH            1024
45 #define NVME_AQ_DEPTH           64
46 #define SQ_SIZE(depth)          (depth * sizeof(struct nvme_command))
47 #define CQ_SIZE(depth)          (depth * sizeof(struct nvme_completion))
48 #define ADMIN_TIMEOUT           (admin_timeout * HZ)
49 #define SHUTDOWN_TIMEOUT        (shutdown_timeout * HZ)
50 #define IOD_TIMEOUT             (retry_time * HZ)
51
52 static unsigned char admin_timeout = 60;
53 module_param(admin_timeout, byte, 0644);
54 MODULE_PARM_DESC(admin_timeout, "timeout in seconds for admin commands");
55
56 unsigned char nvme_io_timeout = 30;
57 module_param_named(io_timeout, nvme_io_timeout, byte, 0644);
58 MODULE_PARM_DESC(io_timeout, "timeout in seconds for I/O");
59
60 static unsigned char retry_time = 30;
61 module_param(retry_time, byte, 0644);
62 MODULE_PARM_DESC(retry_time, "time in seconds to retry failed I/O");
63
64 static unsigned char shutdown_timeout = 5;
65 module_param(shutdown_timeout, byte, 0644);
66 MODULE_PARM_DESC(shutdown_timeout, "timeout in seconds for controller shutdown");
67
68 static int nvme_major;
69 module_param(nvme_major, int, 0);
70
71 static int use_threaded_interrupts;
72 module_param(use_threaded_interrupts, int, 0);
73
74 static DEFINE_SPINLOCK(dev_list_lock);
75 static LIST_HEAD(dev_list);
76 static struct task_struct *nvme_thread;
77 static struct workqueue_struct *nvme_workq;
78 static wait_queue_head_t nvme_kthread_wait;
79 static struct notifier_block nvme_nb;
80
81 static void nvme_reset_failed_dev(struct work_struct *ws);
82 static int nvme_process_cq(struct nvme_queue *nvmeq);
83
84 struct async_cmd_info {
85         struct kthread_work work;
86         struct kthread_worker *worker;
87         struct request *req;
88         u32 result;
89         int status;
90         void *ctx;
91 };
92
93 /*
94  * An NVM Express queue.  Each device has at least two (one for admin
95  * commands and one for I/O commands).
96  */
97 struct nvme_queue {
98         struct llist_node node;
99         struct device *q_dmadev;
100         struct nvme_dev *dev;
101         char irqname[24];       /* nvme4294967295-65535\0 */
102         spinlock_t q_lock;
103         struct nvme_command *sq_cmds;
104         volatile struct nvme_completion *cqes;
105         dma_addr_t sq_dma_addr;
106         dma_addr_t cq_dma_addr;
107         u32 __iomem *q_db;
108         u16 q_depth;
109         u16 cq_vector;
110         u16 sq_head;
111         u16 sq_tail;
112         u16 cq_head;
113         u16 qid;
114         u8 cq_phase;
115         u8 cqe_seen;
116         struct async_cmd_info cmdinfo;
117         struct blk_mq_hw_ctx *hctx;
118 };
119
120 /*
121  * Check we didin't inadvertently grow the command struct
122  */
123 static inline void _nvme_check_size(void)
124 {
125         BUILD_BUG_ON(sizeof(struct nvme_rw_command) != 64);
126         BUILD_BUG_ON(sizeof(struct nvme_create_cq) != 64);
127         BUILD_BUG_ON(sizeof(struct nvme_create_sq) != 64);
128         BUILD_BUG_ON(sizeof(struct nvme_delete_queue) != 64);
129         BUILD_BUG_ON(sizeof(struct nvme_features) != 64);
130         BUILD_BUG_ON(sizeof(struct nvme_format_cmd) != 64);
131         BUILD_BUG_ON(sizeof(struct nvme_abort_cmd) != 64);
132         BUILD_BUG_ON(sizeof(struct nvme_command) != 64);
133         BUILD_BUG_ON(sizeof(struct nvme_id_ctrl) != 4096);
134         BUILD_BUG_ON(sizeof(struct nvme_id_ns) != 4096);
135         BUILD_BUG_ON(sizeof(struct nvme_lba_range_type) != 64);
136         BUILD_BUG_ON(sizeof(struct nvme_smart_log) != 512);
137 }
138
139 typedef void (*nvme_completion_fn)(struct nvme_queue *, void *,
140                                                 struct nvme_completion *);
141
142 struct nvme_cmd_info {
143         nvme_completion_fn fn;
144         void *ctx;
145         int aborted;
146         struct nvme_queue *nvmeq;
147 };
148
149 static int nvme_admin_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
150                                 unsigned int hctx_idx)
151 {
152         struct nvme_dev *dev = data;
153         struct nvme_queue *nvmeq = dev->queues[0];
154
155         WARN_ON(nvmeq->hctx);
156         nvmeq->hctx = hctx;
157         hctx->driver_data = nvmeq;
158         return 0;
159 }
160
161 static int nvme_admin_init_request(void *data, struct request *req,
162                                 unsigned int hctx_idx, unsigned int rq_idx,
163                                 unsigned int numa_node)
164 {
165         struct nvme_dev *dev = data;
166         struct nvme_cmd_info *cmd = blk_mq_rq_to_pdu(req);
167         struct nvme_queue *nvmeq = dev->queues[0];
168
169         BUG_ON(!nvmeq);
170         cmd->nvmeq = nvmeq;
171         return 0;
172 }
173
174 static void nvme_exit_hctx(struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx)
175 {
176         struct nvme_queue *nvmeq = hctx->driver_data;
177
178         nvmeq->hctx = NULL;
179 }
180
181 static int nvme_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
182                           unsigned int hctx_idx)
183 {
184         struct nvme_dev *dev = data;
185         struct nvme_queue *nvmeq = dev->queues[
186                                         (hctx_idx % dev->queue_count) + 1];
187
188         if (!nvmeq->hctx)
189                 nvmeq->hctx = hctx;
190
191         /* nvmeq queues are shared between namespaces. We assume here that
192          * blk-mq map the tags so they match up with the nvme queue tags. */
193         WARN_ON(nvmeq->hctx->tags != hctx->tags);
194
195         hctx->driver_data = nvmeq;
196         return 0;
197 }
198
199 static int nvme_init_request(void *data, struct request *req,
200                                 unsigned int hctx_idx, unsigned int rq_idx,
201                                 unsigned int numa_node)
202 {
203         struct nvme_dev *dev = data;
204         struct nvme_cmd_info *cmd = blk_mq_rq_to_pdu(req);
205         struct nvme_queue *nvmeq = dev->queues[hctx_idx + 1];
206
207         BUG_ON(!nvmeq);
208         cmd->nvmeq = nvmeq;
209         return 0;
210 }
211
212 static void nvme_set_info(struct nvme_cmd_info *cmd, void *ctx,
213                                 nvme_completion_fn handler)
214 {
215         cmd->fn = handler;
216         cmd->ctx = ctx;
217         cmd->aborted = 0;
218 }
219
220 /* Special values must be less than 0x1000 */
221 #define CMD_CTX_BASE            ((void *)POISON_POINTER_DELTA)
222 #define CMD_CTX_CANCELLED       (0x30C + CMD_CTX_BASE)
223 #define CMD_CTX_COMPLETED       (0x310 + CMD_CTX_BASE)
224 #define CMD_CTX_INVALID         (0x314 + CMD_CTX_BASE)
225
226 static void special_completion(struct nvme_queue *nvmeq, void *ctx,
227                                                 struct nvme_completion *cqe)
228 {
229         if (ctx == CMD_CTX_CANCELLED)
230                 return;
231         if (ctx == CMD_CTX_COMPLETED) {
232                 dev_warn(nvmeq->q_dmadev,
233                                 "completed id %d twice on queue %d\n",
234                                 cqe->command_id, le16_to_cpup(&cqe->sq_id));
235                 return;
236         }
237         if (ctx == CMD_CTX_INVALID) {
238                 dev_warn(nvmeq->q_dmadev,
239                                 "invalid id %d completed on queue %d\n",
240                                 cqe->command_id, le16_to_cpup(&cqe->sq_id));
241                 return;
242         }
243         dev_warn(nvmeq->q_dmadev, "Unknown special completion %p\n", ctx);
244 }
245
246 static void *cancel_cmd_info(struct nvme_cmd_info *cmd, nvme_completion_fn *fn)
247 {
248         void *ctx;
249
250         if (fn)
251                 *fn = cmd->fn;
252         ctx = cmd->ctx;
253         cmd->fn = special_completion;
254         cmd->ctx = CMD_CTX_CANCELLED;
255         return ctx;
256 }
257
258 static void async_req_completion(struct nvme_queue *nvmeq, void *ctx,
259                                                 struct nvme_completion *cqe)
260 {
261         struct request *req = ctx;
262
263         u32 result = le32_to_cpup(&cqe->result);
264         u16 status = le16_to_cpup(&cqe->status) >> 1;
265
266         if (status == NVME_SC_SUCCESS || status == NVME_SC_ABORT_REQ)
267                 ++nvmeq->dev->event_limit;
268         if (status == NVME_SC_SUCCESS)
269                 dev_warn(nvmeq->q_dmadev,
270                         "async event result %08x\n", result);
271
272         blk_mq_free_hctx_request(nvmeq->hctx, req);
273 }
274
275 static void abort_completion(struct nvme_queue *nvmeq, void *ctx,
276                                                 struct nvme_completion *cqe)
277 {
278         struct request *req = ctx;
279
280         u16 status = le16_to_cpup(&cqe->status) >> 1;
281         u32 result = le32_to_cpup(&cqe->result);
282
283         blk_mq_free_hctx_request(nvmeq->hctx, req);
284
285         dev_warn(nvmeq->q_dmadev, "Abort status:%x result:%x", status, result);
286         ++nvmeq->dev->abort_limit;
287 }
288
289 static void async_completion(struct nvme_queue *nvmeq, void *ctx,
290                                                 struct nvme_completion *cqe)
291 {
292         struct async_cmd_info *cmdinfo = ctx;
293         cmdinfo->result = le32_to_cpup(&cqe->result);
294         cmdinfo->status = le16_to_cpup(&cqe->status) >> 1;
295         queue_kthread_work(cmdinfo->worker, &cmdinfo->work);
296         blk_mq_free_hctx_request(nvmeq->hctx, cmdinfo->req);
297 }
298
299 static inline struct nvme_cmd_info *get_cmd_from_tag(struct nvme_queue *nvmeq,
300                                   unsigned int tag)
301 {
302         struct blk_mq_hw_ctx *hctx = nvmeq->hctx;
303         struct request *req = blk_mq_tag_to_rq(hctx->tags, tag);
304
305         return blk_mq_rq_to_pdu(req);
306 }
307
308 /*
309  * Called with local interrupts disabled and the q_lock held.  May not sleep.
310  */
311 static void *nvme_finish_cmd(struct nvme_queue *nvmeq, int tag,
312                                                 nvme_completion_fn *fn)
313 {
314         struct nvme_cmd_info *cmd = get_cmd_from_tag(nvmeq, tag);
315         void *ctx;
316         if (tag >= nvmeq->q_depth) {
317                 *fn = special_completion;
318                 return CMD_CTX_INVALID;
319         }
320         if (fn)
321                 *fn = cmd->fn;
322         ctx = cmd->ctx;
323         cmd->fn = special_completion;
324         cmd->ctx = CMD_CTX_COMPLETED;
325         return ctx;
326 }
327
328 /**
329  * nvme_submit_cmd() - Copy a command into a queue and ring the doorbell
330  * @nvmeq: The queue to use
331  * @cmd: The command to send
332  *
333  * Safe to use from interrupt context
334  */
335 static int __nvme_submit_cmd(struct nvme_queue *nvmeq, struct nvme_command *cmd)
336 {
337         u16 tail = nvmeq->sq_tail;
338
339         memcpy(&nvmeq->sq_cmds[tail], cmd, sizeof(*cmd));
340         if (++tail == nvmeq->q_depth)
341                 tail = 0;
342         writel(tail, nvmeq->q_db);
343         nvmeq->sq_tail = tail;
344
345         return 0;
346 }
347
348 static int nvme_submit_cmd(struct nvme_queue *nvmeq, struct nvme_command *cmd)
349 {
350         unsigned long flags;
351         int ret;
352         spin_lock_irqsave(&nvmeq->q_lock, flags);
353         ret = __nvme_submit_cmd(nvmeq, cmd);
354         spin_unlock_irqrestore(&nvmeq->q_lock, flags);
355         return ret;
356 }
357
358 static __le64 **iod_list(struct nvme_iod *iod)
359 {
360         return ((void *)iod) + iod->offset;
361 }
362
363 /*
364  * Will slightly overestimate the number of pages needed.  This is OK
365  * as it only leads to a small amount of wasted memory for the lifetime of
366  * the I/O.
367  */
368 static int nvme_npages(unsigned size, struct nvme_dev *dev)
369 {
370         unsigned nprps = DIV_ROUND_UP(size + dev->page_size, dev->page_size);
371         return DIV_ROUND_UP(8 * nprps, dev->page_size - 8);
372 }
373
374 static struct nvme_iod *
375 nvme_alloc_iod(unsigned nseg, unsigned nbytes, struct nvme_dev *dev, gfp_t gfp)
376 {
377         struct nvme_iod *iod = kmalloc(sizeof(struct nvme_iod) +
378                                 sizeof(__le64 *) * nvme_npages(nbytes, dev) +
379                                 sizeof(struct scatterlist) * nseg, gfp);
380
381         if (iod) {
382                 iod->offset = offsetof(struct nvme_iod, sg[nseg]);
383                 iod->npages = -1;
384                 iod->length = nbytes;
385                 iod->nents = 0;
386                 iod->first_dma = 0ULL;
387         }
388
389         return iod;
390 }
391
392 void nvme_free_iod(struct nvme_dev *dev, struct nvme_iod *iod)
393 {
394         const int last_prp = dev->page_size / 8 - 1;
395         int i;
396         __le64 **list = iod_list(iod);
397         dma_addr_t prp_dma = iod->first_dma;
398
399         if (iod->npages == 0)
400                 dma_pool_free(dev->prp_small_pool, list[0], prp_dma);
401         for (i = 0; i < iod->npages; i++) {
402                 __le64 *prp_list = list[i];
403                 dma_addr_t next_prp_dma = le64_to_cpu(prp_list[last_prp]);
404                 dma_pool_free(dev->prp_page_pool, prp_list, prp_dma);
405                 prp_dma = next_prp_dma;
406         }
407         kfree(iod);
408 }
409
410 static int nvme_error_status(u16 status)
411 {
412         switch (status & 0x7ff) {
413         case NVME_SC_SUCCESS:
414                 return 0;
415         case NVME_SC_CAP_EXCEEDED:
416                 return -ENOSPC;
417         default:
418                 return -EIO;
419         }
420 }
421
422 static void req_completion(struct nvme_queue *nvmeq, void *ctx,
423                                                 struct nvme_completion *cqe)
424 {
425         struct nvme_iod *iod = ctx;
426         struct request *req = iod->private;
427         struct nvme_cmd_info *cmd_rq = blk_mq_rq_to_pdu(req);
428
429         u16 status = le16_to_cpup(&cqe->status) >> 1;
430
431         if (unlikely(status)) {
432                 if (!(status & NVME_SC_DNR || blk_noretry_request(req))
433                     && (jiffies - req->start_time) < req->timeout) {
434                         blk_mq_requeue_request(req);
435                         blk_mq_kick_requeue_list(req->q);
436                         return;
437                 }
438                 req->errors = nvme_error_status(status);
439         } else
440                 req->errors = 0;
441
442         if (cmd_rq->aborted)
443                 dev_warn(&nvmeq->dev->pci_dev->dev,
444                         "completing aborted command with status:%04x\n",
445                         status);
446
447         if (iod->nents)
448                 dma_unmap_sg(&nvmeq->dev->pci_dev->dev, iod->sg, iod->nents,
449                         rq_data_dir(req) ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
450         nvme_free_iod(nvmeq->dev, iod);
451
452         blk_mq_complete_request(req);
453 }
454
455 /* length is in bytes.  gfp flags indicates whether we may sleep. */
456 int nvme_setup_prps(struct nvme_dev *dev, struct nvme_iod *iod, int total_len,
457                                                                 gfp_t gfp)
458 {
459         struct dma_pool *pool;
460         int length = total_len;
461         struct scatterlist *sg = iod->sg;
462         int dma_len = sg_dma_len(sg);
463         u64 dma_addr = sg_dma_address(sg);
464         int offset = offset_in_page(dma_addr);
465         __le64 *prp_list;
466         __le64 **list = iod_list(iod);
467         dma_addr_t prp_dma;
468         int nprps, i;
469         u32 page_size = dev->page_size;
470
471         length -= (page_size - offset);
472         if (length <= 0)
473                 return total_len;
474
475         dma_len -= (page_size - offset);
476         if (dma_len) {
477                 dma_addr += (page_size - offset);
478         } else {
479                 sg = sg_next(sg);
480                 dma_addr = sg_dma_address(sg);
481                 dma_len = sg_dma_len(sg);
482         }
483
484         if (length <= page_size) {
485                 iod->first_dma = dma_addr;
486                 return total_len;
487         }
488
489         nprps = DIV_ROUND_UP(length, page_size);
490         if (nprps <= (256 / 8)) {
491                 pool = dev->prp_small_pool;
492                 iod->npages = 0;
493         } else {
494                 pool = dev->prp_page_pool;
495                 iod->npages = 1;
496         }
497
498         prp_list = dma_pool_alloc(pool, gfp, &prp_dma);
499         if (!prp_list) {
500                 iod->first_dma = dma_addr;
501                 iod->npages = -1;
502                 return (total_len - length) + page_size;
503         }
504         list[0] = prp_list;
505         iod->first_dma = prp_dma;
506         i = 0;
507         for (;;) {
508                 if (i == page_size >> 3) {
509                         __le64 *old_prp_list = prp_list;
510                         prp_list = dma_pool_alloc(pool, gfp, &prp_dma);
511                         if (!prp_list)
512                                 return total_len - length;
513                         list[iod->npages++] = prp_list;
514                         prp_list[0] = old_prp_list[i - 1];
515                         old_prp_list[i - 1] = cpu_to_le64(prp_dma);
516                         i = 1;
517                 }
518                 prp_list[i++] = cpu_to_le64(dma_addr);
519                 dma_len -= page_size;
520                 dma_addr += page_size;
521                 length -= page_size;
522                 if (length <= 0)
523                         break;
524                 if (dma_len > 0)
525                         continue;
526                 BUG_ON(dma_len < 0);
527                 sg = sg_next(sg);
528                 dma_addr = sg_dma_address(sg);
529                 dma_len = sg_dma_len(sg);
530         }
531
532         return total_len;
533 }
534
535 /*
536  * We reuse the small pool to allocate the 16-byte range here as it is not
537  * worth having a special pool for these or additional cases to handle freeing
538  * the iod.
539  */
540 static void nvme_submit_discard(struct nvme_queue *nvmeq, struct nvme_ns *ns,
541                 struct request *req, struct nvme_iod *iod)
542 {
543         struct nvme_dsm_range *range =
544                                 (struct nvme_dsm_range *)iod_list(iod)[0];
545         struct nvme_command *cmnd = &nvmeq->sq_cmds[nvmeq->sq_tail];
546
547         range->cattr = cpu_to_le32(0);
548         range->nlb = cpu_to_le32(blk_rq_bytes(req) >> ns->lba_shift);
549         range->slba = cpu_to_le64(nvme_block_nr(ns, blk_rq_pos(req)));
550
551         memset(cmnd, 0, sizeof(*cmnd));
552         cmnd->dsm.opcode = nvme_cmd_dsm;
553         cmnd->dsm.command_id = req->tag;
554         cmnd->dsm.nsid = cpu_to_le32(ns->ns_id);
555         cmnd->dsm.prp1 = cpu_to_le64(iod->first_dma);
556         cmnd->dsm.nr = 0;
557         cmnd->dsm.attributes = cpu_to_le32(NVME_DSMGMT_AD);
558
559         if (++nvmeq->sq_tail == nvmeq->q_depth)
560                 nvmeq->sq_tail = 0;
561         writel(nvmeq->sq_tail, nvmeq->q_db);
562 }
563
564 static void nvme_submit_flush(struct nvme_queue *nvmeq, struct nvme_ns *ns,
565                                                                 int cmdid)
566 {
567         struct nvme_command *cmnd = &nvmeq->sq_cmds[nvmeq->sq_tail];
568
569         memset(cmnd, 0, sizeof(*cmnd));
570         cmnd->common.opcode = nvme_cmd_flush;
571         cmnd->common.command_id = cmdid;
572         cmnd->common.nsid = cpu_to_le32(ns->ns_id);
573
574         if (++nvmeq->sq_tail == nvmeq->q_depth)
575                 nvmeq->sq_tail = 0;
576         writel(nvmeq->sq_tail, nvmeq->q_db);
577 }
578
579 static int nvme_submit_iod(struct nvme_queue *nvmeq, struct nvme_iod *iod,
580                                                         struct nvme_ns *ns)
581 {
582         struct request *req = iod->private;
583         struct nvme_command *cmnd;
584         u16 control = 0;
585         u32 dsmgmt = 0;
586
587         if (req->cmd_flags & REQ_FUA)
588                 control |= NVME_RW_FUA;
589         if (req->cmd_flags & (REQ_FAILFAST_DEV | REQ_RAHEAD))
590                 control |= NVME_RW_LR;
591
592         if (req->cmd_flags & REQ_RAHEAD)
593                 dsmgmt |= NVME_RW_DSM_FREQ_PREFETCH;
594
595         cmnd = &nvmeq->sq_cmds[nvmeq->sq_tail];
596         memset(cmnd, 0, sizeof(*cmnd));
597
598         cmnd->rw.opcode = (rq_data_dir(req) ? nvme_cmd_write : nvme_cmd_read);
599         cmnd->rw.command_id = req->tag;
600         cmnd->rw.nsid = cpu_to_le32(ns->ns_id);
601         cmnd->rw.prp1 = cpu_to_le64(sg_dma_address(iod->sg));
602         cmnd->rw.prp2 = cpu_to_le64(iod->first_dma);
603         cmnd->rw.slba = cpu_to_le64(nvme_block_nr(ns, blk_rq_pos(req)));
604         cmnd->rw.length = cpu_to_le16((blk_rq_bytes(req) >> ns->lba_shift) - 1);
605         cmnd->rw.control = cpu_to_le16(control);
606         cmnd->rw.dsmgmt = cpu_to_le32(dsmgmt);
607
608         if (++nvmeq->sq_tail == nvmeq->q_depth)
609                 nvmeq->sq_tail = 0;
610         writel(nvmeq->sq_tail, nvmeq->q_db);
611
612         return 0;
613 }
614
615 static int nvme_queue_rq(struct blk_mq_hw_ctx *hctx,
616                          const struct blk_mq_queue_data *bd)
617 {
618         struct nvme_ns *ns = hctx->queue->queuedata;
619         struct nvme_queue *nvmeq = hctx->driver_data;
620         struct request *req = bd->rq;
621         struct nvme_cmd_info *cmd = blk_mq_rq_to_pdu(req);
622         struct nvme_iod *iod;
623         int psegs = req->nr_phys_segments;
624         enum dma_data_direction dma_dir;
625         unsigned size = !(req->cmd_flags & REQ_DISCARD) ? blk_rq_bytes(req) :
626                                                 sizeof(struct nvme_dsm_range);
627
628         iod = nvme_alloc_iod(psegs, size, ns->dev, GFP_ATOMIC);
629         if (!iod)
630                 return BLK_MQ_RQ_QUEUE_BUSY;
631
632         iod->private = req;
633
634         if (req->cmd_flags & REQ_DISCARD) {
635                 void *range;
636                 /*
637                  * We reuse the small pool to allocate the 16-byte range here
638                  * as it is not worth having a special pool for these or
639                  * additional cases to handle freeing the iod.
640                  */
641                 range = dma_pool_alloc(nvmeq->dev->prp_small_pool,
642                                                 GFP_ATOMIC,
643                                                 &iod->first_dma);
644                 if (!range)
645                         goto retry_cmd;
646                 iod_list(iod)[0] = (__le64 *)range;
647                 iod->npages = 0;
648         } else if (psegs) {
649                 dma_dir = rq_data_dir(req) ? DMA_TO_DEVICE : DMA_FROM_DEVICE;
650
651                 sg_init_table(iod->sg, psegs);
652                 iod->nents = blk_rq_map_sg(req->q, req, iod->sg);
653                 if (!iod->nents)
654                         goto error_cmd;
655
656                 if (!dma_map_sg(nvmeq->q_dmadev, iod->sg, iod->nents, dma_dir))
657                         goto retry_cmd;
658
659                 if (blk_rq_bytes(req) !=
660                     nvme_setup_prps(nvmeq->dev, iod, blk_rq_bytes(req), GFP_ATOMIC)) {
661                         dma_unmap_sg(&nvmeq->dev->pci_dev->dev, iod->sg,
662                                         iod->nents, dma_dir);
663                         goto retry_cmd;
664                 }
665         }
666
667         blk_mq_start_request(req);
668
669         nvme_set_info(cmd, iod, req_completion);
670         spin_lock_irq(&nvmeq->q_lock);
671         if (req->cmd_flags & REQ_DISCARD)
672                 nvme_submit_discard(nvmeq, ns, req, iod);
673         else if (req->cmd_flags & REQ_FLUSH)
674                 nvme_submit_flush(nvmeq, ns, req->tag);
675         else
676                 nvme_submit_iod(nvmeq, iod, ns);
677
678         nvme_process_cq(nvmeq);
679         spin_unlock_irq(&nvmeq->q_lock);
680         return BLK_MQ_RQ_QUEUE_OK;
681
682  error_cmd:
683         nvme_free_iod(nvmeq->dev, iod);
684         return BLK_MQ_RQ_QUEUE_ERROR;
685  retry_cmd:
686         nvme_free_iod(nvmeq->dev, iod);
687         return BLK_MQ_RQ_QUEUE_BUSY;
688 }
689
690 static int nvme_process_cq(struct nvme_queue *nvmeq)
691 {
692         u16 head, phase;
693
694         head = nvmeq->cq_head;
695         phase = nvmeq->cq_phase;
696
697         for (;;) {
698                 void *ctx;
699                 nvme_completion_fn fn;
700                 struct nvme_completion cqe = nvmeq->cqes[head];
701                 if ((le16_to_cpu(cqe.status) & 1) != phase)
702                         break;
703                 nvmeq->sq_head = le16_to_cpu(cqe.sq_head);
704                 if (++head == nvmeq->q_depth) {
705                         head = 0;
706                         phase = !phase;
707                 }
708                 ctx = nvme_finish_cmd(nvmeq, cqe.command_id, &fn);
709                 fn(nvmeq, ctx, &cqe);
710         }
711
712         /* If the controller ignores the cq head doorbell and continuously
713          * writes to the queue, it is theoretically possible to wrap around
714          * the queue twice and mistakenly return IRQ_NONE.  Linux only
715          * requires that 0.1% of your interrupts are handled, so this isn't
716          * a big problem.
717          */
718         if (head == nvmeq->cq_head && phase == nvmeq->cq_phase)
719                 return 0;
720
721         writel(head, nvmeq->q_db + nvmeq->dev->db_stride);
722         nvmeq->cq_head = head;
723         nvmeq->cq_phase = phase;
724
725         nvmeq->cqe_seen = 1;
726         return 1;
727 }
728
729 /* Admin queue isn't initialized as a request queue. If at some point this
730  * happens anyway, make sure to notify the user */
731 static int nvme_admin_queue_rq(struct blk_mq_hw_ctx *hctx,
732                                const struct blk_mq_queue_data *bd)
733 {
734         WARN_ON_ONCE(1);
735         return BLK_MQ_RQ_QUEUE_ERROR;
736 }
737
738 static irqreturn_t nvme_irq(int irq, void *data)
739 {
740         irqreturn_t result;
741         struct nvme_queue *nvmeq = data;
742         spin_lock(&nvmeq->q_lock);
743         nvme_process_cq(nvmeq);
744         result = nvmeq->cqe_seen ? IRQ_HANDLED : IRQ_NONE;
745         nvmeq->cqe_seen = 0;
746         spin_unlock(&nvmeq->q_lock);
747         return result;
748 }
749
750 static irqreturn_t nvme_irq_check(int irq, void *data)
751 {
752         struct nvme_queue *nvmeq = data;
753         struct nvme_completion cqe = nvmeq->cqes[nvmeq->cq_head];
754         if ((le16_to_cpu(cqe.status) & 1) != nvmeq->cq_phase)
755                 return IRQ_NONE;
756         return IRQ_WAKE_THREAD;
757 }
758
759 static void nvme_abort_cmd_info(struct nvme_queue *nvmeq, struct nvme_cmd_info *
760                                                                 cmd_info)
761 {
762         spin_lock_irq(&nvmeq->q_lock);
763         cancel_cmd_info(cmd_info, NULL);
764         spin_unlock_irq(&nvmeq->q_lock);
765 }
766
767 struct sync_cmd_info {
768         struct task_struct *task;
769         u32 result;
770         int status;
771 };
772
773 static void sync_completion(struct nvme_queue *nvmeq, void *ctx,
774                                                 struct nvme_completion *cqe)
775 {
776         struct sync_cmd_info *cmdinfo = ctx;
777         cmdinfo->result = le32_to_cpup(&cqe->result);
778         cmdinfo->status = le16_to_cpup(&cqe->status) >> 1;
779         wake_up_process(cmdinfo->task);
780 }
781
782 /*
783  * Returns 0 on success.  If the result is negative, it's a Linux error code;
784  * if the result is positive, it's an NVM Express status code
785  */
786 static int nvme_submit_sync_cmd(struct request *req, struct nvme_command *cmd,
787                                                 u32 *result, unsigned timeout)
788 {
789         int ret;
790         struct sync_cmd_info cmdinfo;
791         struct nvme_cmd_info *cmd_rq = blk_mq_rq_to_pdu(req);
792         struct nvme_queue *nvmeq = cmd_rq->nvmeq;
793
794         cmdinfo.task = current;
795         cmdinfo.status = -EINTR;
796
797         cmd->common.command_id = req->tag;
798
799         nvme_set_info(cmd_rq, &cmdinfo, sync_completion);
800
801         set_current_state(TASK_KILLABLE);
802         ret = nvme_submit_cmd(nvmeq, cmd);
803         if (ret) {
804                 nvme_finish_cmd(nvmeq, req->tag, NULL);
805                 set_current_state(TASK_RUNNING);
806         }
807         ret = schedule_timeout(timeout);
808
809         /*
810          * Ensure that sync_completion has either run, or that it will
811          * never run.
812          */
813         nvme_abort_cmd_info(nvmeq, blk_mq_rq_to_pdu(req));
814
815         /*
816          * We never got the completion
817          */
818         if (cmdinfo.status == -EINTR)
819                 return -EINTR;
820
821         if (result)
822                 *result = cmdinfo.result;
823
824         return cmdinfo.status;
825 }
826
827 static int nvme_submit_async_admin_req(struct nvme_dev *dev)
828 {
829         struct nvme_queue *nvmeq = dev->queues[0];
830         struct nvme_command c;
831         struct nvme_cmd_info *cmd_info;
832         struct request *req;
833
834         req = blk_mq_alloc_request(dev->admin_q, WRITE, GFP_ATOMIC, false);
835         if (IS_ERR(req))
836                 return PTR_ERR(req);
837
838         cmd_info = blk_mq_rq_to_pdu(req);
839         nvme_set_info(cmd_info, req, async_req_completion);
840
841         memset(&c, 0, sizeof(c));
842         c.common.opcode = nvme_admin_async_event;
843         c.common.command_id = req->tag;
844
845         return __nvme_submit_cmd(nvmeq, &c);
846 }
847
848 static int nvme_submit_admin_async_cmd(struct nvme_dev *dev,
849                         struct nvme_command *cmd,
850                         struct async_cmd_info *cmdinfo, unsigned timeout)
851 {
852         struct nvme_queue *nvmeq = dev->queues[0];
853         struct request *req;
854         struct nvme_cmd_info *cmd_rq;
855
856         req = blk_mq_alloc_request(dev->admin_q, WRITE, GFP_KERNEL, false);
857         if (IS_ERR(req))
858                 return PTR_ERR(req);
859
860         req->timeout = timeout;
861         cmd_rq = blk_mq_rq_to_pdu(req);
862         cmdinfo->req = req;
863         nvme_set_info(cmd_rq, cmdinfo, async_completion);
864         cmdinfo->status = -EINTR;
865
866         cmd->common.command_id = req->tag;
867
868         return nvme_submit_cmd(nvmeq, cmd);
869 }
870
871 static int __nvme_submit_admin_cmd(struct nvme_dev *dev, struct nvme_command *cmd,
872                                                 u32 *result, unsigned timeout)
873 {
874         int res;
875         struct request *req;
876
877         req = blk_mq_alloc_request(dev->admin_q, WRITE, GFP_KERNEL, false);
878         if (IS_ERR(req))
879                 return PTR_ERR(req);
880         res = nvme_submit_sync_cmd(req, cmd, result, timeout);
881         blk_mq_free_request(req);
882         return res;
883 }
884
885 int nvme_submit_admin_cmd(struct nvme_dev *dev, struct nvme_command *cmd,
886                                                                 u32 *result)
887 {
888         return __nvme_submit_admin_cmd(dev, cmd, result, ADMIN_TIMEOUT);
889 }
890
891 int nvme_submit_io_cmd(struct nvme_dev *dev, struct nvme_ns *ns,
892                                         struct nvme_command *cmd, u32 *result)
893 {
894         int res;
895         struct request *req;
896
897         req = blk_mq_alloc_request(ns->queue, WRITE, (GFP_KERNEL|__GFP_WAIT),
898                                                                         false);
899         if (IS_ERR(req))
900                 return PTR_ERR(req);
901         res = nvme_submit_sync_cmd(req, cmd, result, NVME_IO_TIMEOUT);
902         blk_mq_free_request(req);
903         return res;
904 }
905
906 static int adapter_delete_queue(struct nvme_dev *dev, u8 opcode, u16 id)
907 {
908         struct nvme_command c;
909
910         memset(&c, 0, sizeof(c));
911         c.delete_queue.opcode = opcode;
912         c.delete_queue.qid = cpu_to_le16(id);
913
914         return nvme_submit_admin_cmd(dev, &c, NULL);
915 }
916
917 static int adapter_alloc_cq(struct nvme_dev *dev, u16 qid,
918                                                 struct nvme_queue *nvmeq)
919 {
920         struct nvme_command c;
921         int flags = NVME_QUEUE_PHYS_CONTIG | NVME_CQ_IRQ_ENABLED;
922
923         memset(&c, 0, sizeof(c));
924         c.create_cq.opcode = nvme_admin_create_cq;
925         c.create_cq.prp1 = cpu_to_le64(nvmeq->cq_dma_addr);
926         c.create_cq.cqid = cpu_to_le16(qid);
927         c.create_cq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
928         c.create_cq.cq_flags = cpu_to_le16(flags);
929         c.create_cq.irq_vector = cpu_to_le16(nvmeq->cq_vector);
930
931         return nvme_submit_admin_cmd(dev, &c, NULL);
932 }
933
934 static int adapter_alloc_sq(struct nvme_dev *dev, u16 qid,
935                                                 struct nvme_queue *nvmeq)
936 {
937         struct nvme_command c;
938         int flags = NVME_QUEUE_PHYS_CONTIG | NVME_SQ_PRIO_MEDIUM;
939
940         memset(&c, 0, sizeof(c));
941         c.create_sq.opcode = nvme_admin_create_sq;
942         c.create_sq.prp1 = cpu_to_le64(nvmeq->sq_dma_addr);
943         c.create_sq.sqid = cpu_to_le16(qid);
944         c.create_sq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
945         c.create_sq.sq_flags = cpu_to_le16(flags);
946         c.create_sq.cqid = cpu_to_le16(qid);
947
948         return nvme_submit_admin_cmd(dev, &c, NULL);
949 }
950
951 static int adapter_delete_cq(struct nvme_dev *dev, u16 cqid)
952 {
953         return adapter_delete_queue(dev, nvme_admin_delete_cq, cqid);
954 }
955
956 static int adapter_delete_sq(struct nvme_dev *dev, u16 sqid)
957 {
958         return adapter_delete_queue(dev, nvme_admin_delete_sq, sqid);
959 }
960
961 int nvme_identify(struct nvme_dev *dev, unsigned nsid, unsigned cns,
962                                                         dma_addr_t dma_addr)
963 {
964         struct nvme_command c;
965
966         memset(&c, 0, sizeof(c));
967         c.identify.opcode = nvme_admin_identify;
968         c.identify.nsid = cpu_to_le32(nsid);
969         c.identify.prp1 = cpu_to_le64(dma_addr);
970         c.identify.cns = cpu_to_le32(cns);
971
972         return nvme_submit_admin_cmd(dev, &c, NULL);
973 }
974
975 int nvme_get_features(struct nvme_dev *dev, unsigned fid, unsigned nsid,
976                                         dma_addr_t dma_addr, u32 *result)
977 {
978         struct nvme_command c;
979
980         memset(&c, 0, sizeof(c));
981         c.features.opcode = nvme_admin_get_features;
982         c.features.nsid = cpu_to_le32(nsid);
983         c.features.prp1 = cpu_to_le64(dma_addr);
984         c.features.fid = cpu_to_le32(fid);
985
986         return nvme_submit_admin_cmd(dev, &c, result);
987 }
988
989 int nvme_set_features(struct nvme_dev *dev, unsigned fid, unsigned dword11,
990                                         dma_addr_t dma_addr, u32 *result)
991 {
992         struct nvme_command c;
993
994         memset(&c, 0, sizeof(c));
995         c.features.opcode = nvme_admin_set_features;
996         c.features.prp1 = cpu_to_le64(dma_addr);
997         c.features.fid = cpu_to_le32(fid);
998         c.features.dword11 = cpu_to_le32(dword11);
999
1000         return nvme_submit_admin_cmd(dev, &c, result);
1001 }
1002
1003 /**
1004  * nvme_abort_req - Attempt aborting a request
1005  *
1006  * Schedule controller reset if the command was already aborted once before and
1007  * still hasn't been returned to the driver, or if this is the admin queue.
1008  */
1009 static void nvme_abort_req(struct request *req)
1010 {
1011         struct nvme_cmd_info *cmd_rq = blk_mq_rq_to_pdu(req);
1012         struct nvme_queue *nvmeq = cmd_rq->nvmeq;
1013         struct nvme_dev *dev = nvmeq->dev;
1014         struct request *abort_req;
1015         struct nvme_cmd_info *abort_cmd;
1016         struct nvme_command cmd;
1017
1018         if (!nvmeq->qid || cmd_rq->aborted) {
1019                 if (work_busy(&dev->reset_work))
1020                         return;
1021                 list_del_init(&dev->node);
1022                 dev_warn(&dev->pci_dev->dev,
1023                         "I/O %d QID %d timeout, reset controller\n",
1024                                                         req->tag, nvmeq->qid);
1025                 dev->reset_workfn = nvme_reset_failed_dev;
1026                 queue_work(nvme_workq, &dev->reset_work);
1027                 return;
1028         }
1029
1030         if (!dev->abort_limit)
1031                 return;
1032
1033         abort_req = blk_mq_alloc_request(dev->admin_q, WRITE, GFP_ATOMIC,
1034                                                                         false);
1035         if (IS_ERR(abort_req))
1036                 return;
1037
1038         abort_cmd = blk_mq_rq_to_pdu(abort_req);
1039         nvme_set_info(abort_cmd, abort_req, abort_completion);
1040
1041         memset(&cmd, 0, sizeof(cmd));
1042         cmd.abort.opcode = nvme_admin_abort_cmd;
1043         cmd.abort.cid = req->tag;
1044         cmd.abort.sqid = cpu_to_le16(nvmeq->qid);
1045         cmd.abort.command_id = abort_req->tag;
1046
1047         --dev->abort_limit;
1048         cmd_rq->aborted = 1;
1049
1050         dev_warn(nvmeq->q_dmadev, "Aborting I/O %d QID %d\n", req->tag,
1051                                                         nvmeq->qid);
1052         if (nvme_submit_cmd(dev->queues[0], &cmd) < 0) {
1053                 dev_warn(nvmeq->q_dmadev,
1054                                 "Could not abort I/O %d QID %d",
1055                                 req->tag, nvmeq->qid);
1056                 blk_mq_free_request(abort_req);
1057         }
1058 }
1059
1060 static void nvme_cancel_queue_ios(struct blk_mq_hw_ctx *hctx,
1061                                 struct request *req, void *data, bool reserved)
1062 {
1063         struct nvme_queue *nvmeq = data;
1064         void *ctx;
1065         nvme_completion_fn fn;
1066         struct nvme_cmd_info *cmd;
1067         static struct nvme_completion cqe = {
1068                 .status = cpu_to_le16(NVME_SC_ABORT_REQ << 1),
1069         };
1070
1071         cmd = blk_mq_rq_to_pdu(req);
1072
1073         if (cmd->ctx == CMD_CTX_CANCELLED)
1074                 return;
1075
1076         dev_warn(nvmeq->q_dmadev, "Cancelling I/O %d QID %d\n",
1077                                                 req->tag, nvmeq->qid);
1078         ctx = cancel_cmd_info(cmd, &fn);
1079         fn(nvmeq, ctx, &cqe);
1080 }
1081
1082 static enum blk_eh_timer_return nvme_timeout(struct request *req, bool reserved)
1083 {
1084         struct nvme_cmd_info *cmd = blk_mq_rq_to_pdu(req);
1085         struct nvme_queue *nvmeq = cmd->nvmeq;
1086
1087         dev_warn(nvmeq->q_dmadev, "Timeout I/O %d QID %d\n", req->tag,
1088                                                         nvmeq->qid);
1089         if (nvmeq->dev->initialized)
1090                 nvme_abort_req(req);
1091
1092         /*
1093          * The aborted req will be completed on receiving the abort req.
1094          * We enable the timer again. If hit twice, it'll cause a device reset,
1095          * as the device then is in a faulty state.
1096          */
1097         return BLK_EH_RESET_TIMER;
1098 }
1099
1100 static void nvme_free_queue(struct nvme_queue *nvmeq)
1101 {
1102         dma_free_coherent(nvmeq->q_dmadev, CQ_SIZE(nvmeq->q_depth),
1103                                 (void *)nvmeq->cqes, nvmeq->cq_dma_addr);
1104         dma_free_coherent(nvmeq->q_dmadev, SQ_SIZE(nvmeq->q_depth),
1105                                         nvmeq->sq_cmds, nvmeq->sq_dma_addr);
1106         kfree(nvmeq);
1107 }
1108
1109 static void nvme_free_queues(struct nvme_dev *dev, int lowest)
1110 {
1111         LLIST_HEAD(q_list);
1112         struct nvme_queue *nvmeq, *next;
1113         struct llist_node *entry;
1114         int i;
1115
1116         for (i = dev->queue_count - 1; i >= lowest; i--) {
1117                 struct nvme_queue *nvmeq = dev->queues[i];
1118                 llist_add(&nvmeq->node, &q_list);
1119                 dev->queue_count--;
1120                 dev->queues[i] = NULL;
1121         }
1122         synchronize_rcu();
1123         entry = llist_del_all(&q_list);
1124         llist_for_each_entry_safe(nvmeq, next, entry, node)
1125                 nvme_free_queue(nvmeq);
1126 }
1127
1128 /**
1129  * nvme_suspend_queue - put queue into suspended state
1130  * @nvmeq - queue to suspend
1131  */
1132 static int nvme_suspend_queue(struct nvme_queue *nvmeq)
1133 {
1134         int vector = nvmeq->dev->entry[nvmeq->cq_vector].vector;
1135
1136         spin_lock_irq(&nvmeq->q_lock);
1137         nvmeq->dev->online_queues--;
1138         spin_unlock_irq(&nvmeq->q_lock);
1139
1140         irq_set_affinity_hint(vector, NULL);
1141         free_irq(vector, nvmeq);
1142
1143         return 0;
1144 }
1145
1146 static void nvme_clear_queue(struct nvme_queue *nvmeq)
1147 {
1148         struct blk_mq_hw_ctx *hctx = nvmeq->hctx;
1149
1150         spin_lock_irq(&nvmeq->q_lock);
1151         nvme_process_cq(nvmeq);
1152         if (hctx && hctx->tags)
1153                 blk_mq_tag_busy_iter(hctx, nvme_cancel_queue_ios, nvmeq);
1154         spin_unlock_irq(&nvmeq->q_lock);
1155 }
1156
1157 static void nvme_disable_queue(struct nvme_dev *dev, int qid)
1158 {
1159         struct nvme_queue *nvmeq = dev->queues[qid];
1160
1161         if (!nvmeq)
1162                 return;
1163         if (nvme_suspend_queue(nvmeq))
1164                 return;
1165
1166         /* Don't tell the adapter to delete the admin queue.
1167          * Don't tell a removed adapter to delete IO queues. */
1168         if (qid && readl(&dev->bar->csts) != -1) {
1169                 adapter_delete_sq(dev, qid);
1170                 adapter_delete_cq(dev, qid);
1171         }
1172         nvme_clear_queue(nvmeq);
1173 }
1174
1175 static struct nvme_queue *nvme_alloc_queue(struct nvme_dev *dev, int qid,
1176                                                         int depth, int vector)
1177 {
1178         struct device *dmadev = &dev->pci_dev->dev;
1179         struct nvme_queue *nvmeq = kzalloc(sizeof(*nvmeq), GFP_KERNEL);
1180         if (!nvmeq)
1181                 return NULL;
1182
1183         nvmeq->cqes = dma_zalloc_coherent(dmadev, CQ_SIZE(depth),
1184                                           &nvmeq->cq_dma_addr, GFP_KERNEL);
1185         if (!nvmeq->cqes)
1186                 goto free_nvmeq;
1187
1188         nvmeq->sq_cmds = dma_alloc_coherent(dmadev, SQ_SIZE(depth),
1189                                         &nvmeq->sq_dma_addr, GFP_KERNEL);
1190         if (!nvmeq->sq_cmds)
1191                 goto free_cqdma;
1192
1193         nvmeq->q_dmadev = dmadev;
1194         nvmeq->dev = dev;
1195         snprintf(nvmeq->irqname, sizeof(nvmeq->irqname), "nvme%dq%d",
1196                         dev->instance, qid);
1197         spin_lock_init(&nvmeq->q_lock);
1198         nvmeq->cq_head = 0;
1199         nvmeq->cq_phase = 1;
1200         nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
1201         nvmeq->q_depth = depth;
1202         nvmeq->cq_vector = vector;
1203         nvmeq->qid = qid;
1204         dev->queue_count++;
1205         dev->queues[qid] = nvmeq;
1206
1207         return nvmeq;
1208
1209  free_cqdma:
1210         dma_free_coherent(dmadev, CQ_SIZE(depth), (void *)nvmeq->cqes,
1211                                                         nvmeq->cq_dma_addr);
1212  free_nvmeq:
1213         kfree(nvmeq);
1214         return NULL;
1215 }
1216
1217 static int queue_request_irq(struct nvme_dev *dev, struct nvme_queue *nvmeq,
1218                                                         const char *name)
1219 {
1220         if (use_threaded_interrupts)
1221                 return request_threaded_irq(dev->entry[nvmeq->cq_vector].vector,
1222                                         nvme_irq_check, nvme_irq, IRQF_SHARED,
1223                                         name, nvmeq);
1224         return request_irq(dev->entry[nvmeq->cq_vector].vector, nvme_irq,
1225                                 IRQF_SHARED, name, nvmeq);
1226 }
1227
1228 static void nvme_init_queue(struct nvme_queue *nvmeq, u16 qid)
1229 {
1230         struct nvme_dev *dev = nvmeq->dev;
1231
1232         spin_lock_irq(&nvmeq->q_lock);
1233         nvmeq->sq_tail = 0;
1234         nvmeq->cq_head = 0;
1235         nvmeq->cq_phase = 1;
1236         nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
1237         memset((void *)nvmeq->cqes, 0, CQ_SIZE(nvmeq->q_depth));
1238         dev->online_queues++;
1239         spin_unlock_irq(&nvmeq->q_lock);
1240 }
1241
1242 static int nvme_create_queue(struct nvme_queue *nvmeq, int qid)
1243 {
1244         struct nvme_dev *dev = nvmeq->dev;
1245         int result;
1246
1247         result = adapter_alloc_cq(dev, qid, nvmeq);
1248         if (result < 0)
1249                 return result;
1250
1251         result = adapter_alloc_sq(dev, qid, nvmeq);
1252         if (result < 0)
1253                 goto release_cq;
1254
1255         result = queue_request_irq(dev, nvmeq, nvmeq->irqname);
1256         if (result < 0)
1257                 goto release_sq;
1258
1259         nvme_init_queue(nvmeq, qid);
1260         return result;
1261
1262  release_sq:
1263         adapter_delete_sq(dev, qid);
1264  release_cq:
1265         adapter_delete_cq(dev, qid);
1266         return result;
1267 }
1268
1269 static int nvme_wait_ready(struct nvme_dev *dev, u64 cap, bool enabled)
1270 {
1271         unsigned long timeout;
1272         u32 bit = enabled ? NVME_CSTS_RDY : 0;
1273
1274         timeout = ((NVME_CAP_TIMEOUT(cap) + 1) * HZ / 2) + jiffies;
1275
1276         while ((readl(&dev->bar->csts) & NVME_CSTS_RDY) != bit) {
1277                 msleep(100);
1278                 if (fatal_signal_pending(current))
1279                         return -EINTR;
1280                 if (time_after(jiffies, timeout)) {
1281                         dev_err(&dev->pci_dev->dev,
1282                                 "Device not ready; aborting %s\n", enabled ?
1283                                                 "initialisation" : "reset");
1284                         return -ENODEV;
1285                 }
1286         }
1287
1288         return 0;
1289 }
1290
1291 /*
1292  * If the device has been passed off to us in an enabled state, just clear
1293  * the enabled bit.  The spec says we should set the 'shutdown notification
1294  * bits', but doing so may cause the device to complete commands to the
1295  * admin queue ... and we don't know what memory that might be pointing at!
1296  */
1297 static int nvme_disable_ctrl(struct nvme_dev *dev, u64 cap)
1298 {
1299         dev->ctrl_config &= ~NVME_CC_SHN_MASK;
1300         dev->ctrl_config &= ~NVME_CC_ENABLE;
1301         writel(dev->ctrl_config, &dev->bar->cc);
1302
1303         return nvme_wait_ready(dev, cap, false);
1304 }
1305
1306 static int nvme_enable_ctrl(struct nvme_dev *dev, u64 cap)
1307 {
1308         dev->ctrl_config &= ~NVME_CC_SHN_MASK;
1309         dev->ctrl_config |= NVME_CC_ENABLE;
1310         writel(dev->ctrl_config, &dev->bar->cc);
1311
1312         return nvme_wait_ready(dev, cap, true);
1313 }
1314
1315 static int nvme_shutdown_ctrl(struct nvme_dev *dev)
1316 {
1317         unsigned long timeout;
1318
1319         dev->ctrl_config &= ~NVME_CC_SHN_MASK;
1320         dev->ctrl_config |= NVME_CC_SHN_NORMAL;
1321
1322         writel(dev->ctrl_config, &dev->bar->cc);
1323
1324         timeout = SHUTDOWN_TIMEOUT + jiffies;
1325         while ((readl(&dev->bar->csts) & NVME_CSTS_SHST_MASK) !=
1326                                                         NVME_CSTS_SHST_CMPLT) {
1327                 msleep(100);
1328                 if (fatal_signal_pending(current))
1329                         return -EINTR;
1330                 if (time_after(jiffies, timeout)) {
1331                         dev_err(&dev->pci_dev->dev,
1332                                 "Device shutdown incomplete; abort shutdown\n");
1333                         return -ENODEV;
1334                 }
1335         }
1336
1337         return 0;
1338 }
1339
1340 static struct blk_mq_ops nvme_mq_admin_ops = {
1341         .queue_rq       = nvme_admin_queue_rq,
1342         .map_queue      = blk_mq_map_queue,
1343         .init_hctx      = nvme_admin_init_hctx,
1344         .exit_hctx      = nvme_exit_hctx,
1345         .init_request   = nvme_admin_init_request,
1346         .timeout        = nvme_timeout,
1347 };
1348
1349 static struct blk_mq_ops nvme_mq_ops = {
1350         .queue_rq       = nvme_queue_rq,
1351         .map_queue      = blk_mq_map_queue,
1352         .init_hctx      = nvme_init_hctx,
1353         .exit_hctx      = nvme_exit_hctx,
1354         .init_request   = nvme_init_request,
1355         .timeout        = nvme_timeout,
1356 };
1357
1358 static int nvme_alloc_admin_tags(struct nvme_dev *dev)
1359 {
1360         if (!dev->admin_q) {
1361                 dev->admin_tagset.ops = &nvme_mq_admin_ops;
1362                 dev->admin_tagset.nr_hw_queues = 1;
1363                 dev->admin_tagset.queue_depth = NVME_AQ_DEPTH - 1;
1364                 dev->admin_tagset.timeout = ADMIN_TIMEOUT;
1365                 dev->admin_tagset.numa_node = dev_to_node(&dev->pci_dev->dev);
1366                 dev->admin_tagset.cmd_size = sizeof(struct nvme_cmd_info);
1367                 dev->admin_tagset.driver_data = dev;
1368
1369                 if (blk_mq_alloc_tag_set(&dev->admin_tagset))
1370                         return -ENOMEM;
1371
1372                 dev->admin_q = blk_mq_init_queue(&dev->admin_tagset);
1373                 if (!dev->admin_q) {
1374                         blk_mq_free_tag_set(&dev->admin_tagset);
1375                         return -ENOMEM;
1376                 }
1377         }
1378
1379         return 0;
1380 }
1381
1382 static void nvme_free_admin_tags(struct nvme_dev *dev)
1383 {
1384         if (dev->admin_q)
1385                 blk_mq_free_tag_set(&dev->admin_tagset);
1386 }
1387
1388 static int nvme_configure_admin_queue(struct nvme_dev *dev)
1389 {
1390         int result;
1391         u32 aqa;
1392         u64 cap = readq(&dev->bar->cap);
1393         struct nvme_queue *nvmeq;
1394         unsigned page_shift = PAGE_SHIFT;
1395         unsigned dev_page_min = NVME_CAP_MPSMIN(cap) + 12;
1396         unsigned dev_page_max = NVME_CAP_MPSMAX(cap) + 12;
1397
1398         if (page_shift < dev_page_min) {
1399                 dev_err(&dev->pci_dev->dev,
1400                                 "Minimum device page size (%u) too large for "
1401                                 "host (%u)\n", 1 << dev_page_min,
1402                                 1 << page_shift);
1403                 return -ENODEV;
1404         }
1405         if (page_shift > dev_page_max) {
1406                 dev_info(&dev->pci_dev->dev,
1407                                 "Device maximum page size (%u) smaller than "
1408                                 "host (%u); enabling work-around\n",
1409                                 1 << dev_page_max, 1 << page_shift);
1410                 page_shift = dev_page_max;
1411         }
1412
1413         result = nvme_disable_ctrl(dev, cap);
1414         if (result < 0)
1415                 return result;
1416
1417         nvmeq = dev->queues[0];
1418         if (!nvmeq) {
1419                 nvmeq = nvme_alloc_queue(dev, 0, NVME_AQ_DEPTH, 0);
1420                 if (!nvmeq)
1421                         return -ENOMEM;
1422         }
1423
1424         aqa = nvmeq->q_depth - 1;
1425         aqa |= aqa << 16;
1426
1427         dev->page_size = 1 << page_shift;
1428
1429         dev->ctrl_config = NVME_CC_CSS_NVM;
1430         dev->ctrl_config |= (page_shift - 12) << NVME_CC_MPS_SHIFT;
1431         dev->ctrl_config |= NVME_CC_ARB_RR | NVME_CC_SHN_NONE;
1432         dev->ctrl_config |= NVME_CC_IOSQES | NVME_CC_IOCQES;
1433
1434         writel(aqa, &dev->bar->aqa);
1435         writeq(nvmeq->sq_dma_addr, &dev->bar->asq);
1436         writeq(nvmeq->cq_dma_addr, &dev->bar->acq);
1437
1438         result = nvme_enable_ctrl(dev, cap);
1439         if (result)
1440                 goto free_nvmeq;
1441
1442         result = nvme_alloc_admin_tags(dev);
1443         if (result)
1444                 goto free_nvmeq;
1445
1446         result = queue_request_irq(dev, nvmeq, nvmeq->irqname);
1447         if (result)
1448                 goto free_tags;
1449
1450         return result;
1451
1452  free_tags:
1453         nvme_free_admin_tags(dev);
1454  free_nvmeq:
1455         nvme_free_queues(dev, 0);
1456         return result;
1457 }
1458
1459 struct nvme_iod *nvme_map_user_pages(struct nvme_dev *dev, int write,
1460                                 unsigned long addr, unsigned length)
1461 {
1462         int i, err, count, nents, offset;
1463         struct scatterlist *sg;
1464         struct page **pages;
1465         struct nvme_iod *iod;
1466
1467         if (addr & 3)
1468                 return ERR_PTR(-EINVAL);
1469         if (!length || length > INT_MAX - PAGE_SIZE)
1470                 return ERR_PTR(-EINVAL);
1471
1472         offset = offset_in_page(addr);
1473         count = DIV_ROUND_UP(offset + length, PAGE_SIZE);
1474         pages = kcalloc(count, sizeof(*pages), GFP_KERNEL);
1475         if (!pages)
1476                 return ERR_PTR(-ENOMEM);
1477
1478         err = get_user_pages_fast(addr, count, 1, pages);
1479         if (err < count) {
1480                 count = err;
1481                 err = -EFAULT;
1482                 goto put_pages;
1483         }
1484
1485         err = -ENOMEM;
1486         iod = nvme_alloc_iod(count, length, dev, GFP_KERNEL);
1487         if (!iod)
1488                 goto put_pages;
1489
1490         sg = iod->sg;
1491         sg_init_table(sg, count);
1492         for (i = 0; i < count; i++) {
1493                 sg_set_page(&sg[i], pages[i],
1494                             min_t(unsigned, length, PAGE_SIZE - offset),
1495                             offset);
1496                 length -= (PAGE_SIZE - offset);
1497                 offset = 0;
1498         }
1499         sg_mark_end(&sg[i - 1]);
1500         iod->nents = count;
1501
1502         nents = dma_map_sg(&dev->pci_dev->dev, sg, count,
1503                                 write ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
1504         if (!nents)
1505                 goto free_iod;
1506
1507         kfree(pages);
1508         return iod;
1509
1510  free_iod:
1511         kfree(iod);
1512  put_pages:
1513         for (i = 0; i < count; i++)
1514                 put_page(pages[i]);
1515         kfree(pages);
1516         return ERR_PTR(err);
1517 }
1518
1519 void nvme_unmap_user_pages(struct nvme_dev *dev, int write,
1520                         struct nvme_iod *iod)
1521 {
1522         int i;
1523
1524         dma_unmap_sg(&dev->pci_dev->dev, iod->sg, iod->nents,
1525                                 write ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
1526
1527         for (i = 0; i < iod->nents; i++)
1528                 put_page(sg_page(&iod->sg[i]));
1529 }
1530
1531 static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio)
1532 {
1533         struct nvme_dev *dev = ns->dev;
1534         struct nvme_user_io io;
1535         struct nvme_command c;
1536         unsigned length, meta_len;
1537         int status, i;
1538         struct nvme_iod *iod, *meta_iod = NULL;
1539         dma_addr_t meta_dma_addr;
1540         void *meta, *uninitialized_var(meta_mem);
1541
1542         if (copy_from_user(&io, uio, sizeof(io)))
1543                 return -EFAULT;
1544         length = (io.nblocks + 1) << ns->lba_shift;
1545         meta_len = (io.nblocks + 1) * ns->ms;
1546
1547         if (meta_len && ((io.metadata & 3) || !io.metadata))
1548                 return -EINVAL;
1549
1550         switch (io.opcode) {
1551         case nvme_cmd_write:
1552         case nvme_cmd_read:
1553         case nvme_cmd_compare:
1554                 iod = nvme_map_user_pages(dev, io.opcode & 1, io.addr, length);
1555                 break;
1556         default:
1557                 return -EINVAL;
1558         }
1559
1560         if (IS_ERR(iod))
1561                 return PTR_ERR(iod);
1562
1563         memset(&c, 0, sizeof(c));
1564         c.rw.opcode = io.opcode;
1565         c.rw.flags = io.flags;
1566         c.rw.nsid = cpu_to_le32(ns->ns_id);
1567         c.rw.slba = cpu_to_le64(io.slba);
1568         c.rw.length = cpu_to_le16(io.nblocks);
1569         c.rw.control = cpu_to_le16(io.control);
1570         c.rw.dsmgmt = cpu_to_le32(io.dsmgmt);
1571         c.rw.reftag = cpu_to_le32(io.reftag);
1572         c.rw.apptag = cpu_to_le16(io.apptag);
1573         c.rw.appmask = cpu_to_le16(io.appmask);
1574
1575         if (meta_len) {
1576                 meta_iod = nvme_map_user_pages(dev, io.opcode & 1, io.metadata,
1577                                                                 meta_len);
1578                 if (IS_ERR(meta_iod)) {
1579                         status = PTR_ERR(meta_iod);
1580                         meta_iod = NULL;
1581                         goto unmap;
1582                 }
1583
1584                 meta_mem = dma_alloc_coherent(&dev->pci_dev->dev, meta_len,
1585                                                 &meta_dma_addr, GFP_KERNEL);
1586                 if (!meta_mem) {
1587                         status = -ENOMEM;
1588                         goto unmap;
1589                 }
1590
1591                 if (io.opcode & 1) {
1592                         int meta_offset = 0;
1593
1594                         for (i = 0; i < meta_iod->nents; i++) {
1595                                 meta = kmap_atomic(sg_page(&meta_iod->sg[i])) +
1596                                                 meta_iod->sg[i].offset;
1597                                 memcpy(meta_mem + meta_offset, meta,
1598                                                 meta_iod->sg[i].length);
1599                                 kunmap_atomic(meta);
1600                                 meta_offset += meta_iod->sg[i].length;
1601                         }
1602                 }
1603
1604                 c.rw.metadata = cpu_to_le64(meta_dma_addr);
1605         }
1606
1607         length = nvme_setup_prps(dev, iod, length, GFP_KERNEL);
1608         c.rw.prp1 = cpu_to_le64(sg_dma_address(iod->sg));
1609         c.rw.prp2 = cpu_to_le64(iod->first_dma);
1610
1611         if (length != (io.nblocks + 1) << ns->lba_shift)
1612                 status = -ENOMEM;
1613         else
1614                 status = nvme_submit_io_cmd(dev, ns, &c, NULL);
1615
1616         if (meta_len) {
1617                 if (status == NVME_SC_SUCCESS && !(io.opcode & 1)) {
1618                         int meta_offset = 0;
1619
1620                         for (i = 0; i < meta_iod->nents; i++) {
1621                                 meta = kmap_atomic(sg_page(&meta_iod->sg[i])) +
1622                                                 meta_iod->sg[i].offset;
1623                                 memcpy(meta, meta_mem + meta_offset,
1624                                                 meta_iod->sg[i].length);
1625                                 kunmap_atomic(meta);
1626                                 meta_offset += meta_iod->sg[i].length;
1627                         }
1628                 }
1629
1630                 dma_free_coherent(&dev->pci_dev->dev, meta_len, meta_mem,
1631                                                                 meta_dma_addr);
1632         }
1633
1634  unmap:
1635         nvme_unmap_user_pages(dev, io.opcode & 1, iod);
1636         nvme_free_iod(dev, iod);
1637
1638         if (meta_iod) {
1639                 nvme_unmap_user_pages(dev, io.opcode & 1, meta_iod);
1640                 nvme_free_iod(dev, meta_iod);
1641         }
1642
1643         return status;
1644 }
1645
1646 static int nvme_user_cmd(struct nvme_dev *dev, struct nvme_ns *ns,
1647                         struct nvme_passthru_cmd __user *ucmd)
1648 {
1649         struct nvme_passthru_cmd cmd;
1650         struct nvme_command c;
1651         int status, length;
1652         struct nvme_iod *uninitialized_var(iod);
1653         unsigned timeout;
1654
1655         if (!capable(CAP_SYS_ADMIN))
1656                 return -EACCES;
1657         if (copy_from_user(&cmd, ucmd, sizeof(cmd)))
1658                 return -EFAULT;
1659
1660         memset(&c, 0, sizeof(c));
1661         c.common.opcode = cmd.opcode;
1662         c.common.flags = cmd.flags;
1663         c.common.nsid = cpu_to_le32(cmd.nsid);
1664         c.common.cdw2[0] = cpu_to_le32(cmd.cdw2);
1665         c.common.cdw2[1] = cpu_to_le32(cmd.cdw3);
1666         c.common.cdw10[0] = cpu_to_le32(cmd.cdw10);
1667         c.common.cdw10[1] = cpu_to_le32(cmd.cdw11);
1668         c.common.cdw10[2] = cpu_to_le32(cmd.cdw12);
1669         c.common.cdw10[3] = cpu_to_le32(cmd.cdw13);
1670         c.common.cdw10[4] = cpu_to_le32(cmd.cdw14);
1671         c.common.cdw10[5] = cpu_to_le32(cmd.cdw15);
1672
1673         length = cmd.data_len;
1674         if (cmd.data_len) {
1675                 iod = nvme_map_user_pages(dev, cmd.opcode & 1, cmd.addr,
1676                                                                 length);
1677                 if (IS_ERR(iod))
1678                         return PTR_ERR(iod);
1679                 length = nvme_setup_prps(dev, iod, length, GFP_KERNEL);
1680                 c.common.prp1 = cpu_to_le64(sg_dma_address(iod->sg));
1681                 c.common.prp2 = cpu_to_le64(iod->first_dma);
1682         }
1683
1684         timeout = cmd.timeout_ms ? msecs_to_jiffies(cmd.timeout_ms) :
1685                                                                 ADMIN_TIMEOUT;
1686
1687         if (length != cmd.data_len)
1688                 status = -ENOMEM;
1689         else if (ns) {
1690                 struct request *req;
1691
1692                 req = blk_mq_alloc_request(ns->queue, WRITE,
1693                                                 (GFP_KERNEL|__GFP_WAIT), false);
1694                 if (IS_ERR(req))
1695                         status = PTR_ERR(req);
1696                 else {
1697                         status = nvme_submit_sync_cmd(req, &c, &cmd.result,
1698                                                                 timeout);
1699                         blk_mq_free_request(req);
1700                 }
1701         } else
1702                 status = __nvme_submit_admin_cmd(dev, &c, &cmd.result, timeout);
1703
1704         if (cmd.data_len) {
1705                 nvme_unmap_user_pages(dev, cmd.opcode & 1, iod);
1706                 nvme_free_iod(dev, iod);
1707         }
1708
1709         if ((status >= 0) && copy_to_user(&ucmd->result, &cmd.result,
1710                                                         sizeof(cmd.result)))
1711                 status = -EFAULT;
1712
1713         return status;
1714 }
1715
1716 static int nvme_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd,
1717                                                         unsigned long arg)
1718 {
1719         struct nvme_ns *ns = bdev->bd_disk->private_data;
1720
1721         switch (cmd) {
1722         case NVME_IOCTL_ID:
1723                 force_successful_syscall_return();
1724                 return ns->ns_id;
1725         case NVME_IOCTL_ADMIN_CMD:
1726                 return nvme_user_cmd(ns->dev, NULL, (void __user *)arg);
1727         case NVME_IOCTL_IO_CMD:
1728                 return nvme_user_cmd(ns->dev, ns, (void __user *)arg);
1729         case NVME_IOCTL_SUBMIT_IO:
1730                 return nvme_submit_io(ns, (void __user *)arg);
1731         case SG_GET_VERSION_NUM:
1732                 return nvme_sg_get_version_num((void __user *)arg);
1733         case SG_IO:
1734                 return nvme_sg_io(ns, (void __user *)arg);
1735         default:
1736                 return -ENOTTY;
1737         }
1738 }
1739
1740 #ifdef CONFIG_COMPAT
1741 static int nvme_compat_ioctl(struct block_device *bdev, fmode_t mode,
1742                                         unsigned int cmd, unsigned long arg)
1743 {
1744         switch (cmd) {
1745         case SG_IO:
1746                 return -ENOIOCTLCMD;
1747         }
1748         return nvme_ioctl(bdev, mode, cmd, arg);
1749 }
1750 #else
1751 #define nvme_compat_ioctl       NULL
1752 #endif
1753
1754 static int nvme_open(struct block_device *bdev, fmode_t mode)
1755 {
1756         int ret = 0;
1757         struct nvme_ns *ns;
1758
1759         spin_lock(&dev_list_lock);
1760         ns = bdev->bd_disk->private_data;
1761         if (!ns)
1762                 ret = -ENXIO;
1763         else if (!kref_get_unless_zero(&ns->dev->kref))
1764                 ret = -ENXIO;
1765         spin_unlock(&dev_list_lock);
1766
1767         return ret;
1768 }
1769
1770 static void nvme_free_dev(struct kref *kref);
1771
1772 static void nvme_release(struct gendisk *disk, fmode_t mode)
1773 {
1774         struct nvme_ns *ns = disk->private_data;
1775         struct nvme_dev *dev = ns->dev;
1776
1777         kref_put(&dev->kref, nvme_free_dev);
1778 }
1779
1780 static int nvme_getgeo(struct block_device *bd, struct hd_geometry *geo)
1781 {
1782         /* some standard values */
1783         geo->heads = 1 << 6;
1784         geo->sectors = 1 << 5;
1785         geo->cylinders = get_capacity(bd->bd_disk) >> 11;
1786         return 0;
1787 }
1788
1789 static int nvme_revalidate_disk(struct gendisk *disk)
1790 {
1791         struct nvme_ns *ns = disk->private_data;
1792         struct nvme_dev *dev = ns->dev;
1793         struct nvme_id_ns *id;
1794         dma_addr_t dma_addr;
1795         int lbaf;
1796
1797         id = dma_alloc_coherent(&dev->pci_dev->dev, 4096, &dma_addr,
1798                                                                 GFP_KERNEL);
1799         if (!id) {
1800                 dev_warn(&dev->pci_dev->dev, "%s: Memory alocation failure\n",
1801                                                                 __func__);
1802                 return 0;
1803         }
1804
1805         if (nvme_identify(dev, ns->ns_id, 0, dma_addr))
1806                 goto free;
1807
1808         lbaf = id->flbas & 0xf;
1809         ns->lba_shift = id->lbaf[lbaf].ds;
1810
1811         blk_queue_logical_block_size(ns->queue, 1 << ns->lba_shift);
1812         set_capacity(disk, le64_to_cpup(&id->nsze) << (ns->lba_shift - 9));
1813  free:
1814         dma_free_coherent(&dev->pci_dev->dev, 4096, id, dma_addr);
1815         return 0;
1816 }
1817
1818 static const struct block_device_operations nvme_fops = {
1819         .owner          = THIS_MODULE,
1820         .ioctl          = nvme_ioctl,
1821         .compat_ioctl   = nvme_compat_ioctl,
1822         .open           = nvme_open,
1823         .release        = nvme_release,
1824         .getgeo         = nvme_getgeo,
1825         .revalidate_disk= nvme_revalidate_disk,
1826 };
1827
1828 static int nvme_kthread(void *data)
1829 {
1830         struct nvme_dev *dev, *next;
1831
1832         while (!kthread_should_stop()) {
1833                 set_current_state(TASK_INTERRUPTIBLE);
1834                 spin_lock(&dev_list_lock);
1835                 list_for_each_entry_safe(dev, next, &dev_list, node) {
1836                         int i;
1837                         if (readl(&dev->bar->csts) & NVME_CSTS_CFS &&
1838                                                         dev->initialized) {
1839                                 if (work_busy(&dev->reset_work))
1840                                         continue;
1841                                 list_del_init(&dev->node);
1842                                 dev_warn(&dev->pci_dev->dev,
1843                                         "Failed status: %x, reset controller\n",
1844                                         readl(&dev->bar->csts));
1845                                 dev->reset_workfn = nvme_reset_failed_dev;
1846                                 queue_work(nvme_workq, &dev->reset_work);
1847                                 continue;
1848                         }
1849                         for (i = 0; i < dev->queue_count; i++) {
1850                                 struct nvme_queue *nvmeq = dev->queues[i];
1851                                 if (!nvmeq)
1852                                         continue;
1853                                 spin_lock_irq(&nvmeq->q_lock);
1854                                 nvme_process_cq(nvmeq);
1855
1856                                 while ((i == 0) && (dev->event_limit > 0)) {
1857                                         if (nvme_submit_async_admin_req(dev))
1858                                                 break;
1859                                         dev->event_limit--;
1860                                 }
1861                                 spin_unlock_irq(&nvmeq->q_lock);
1862                         }
1863                 }
1864                 spin_unlock(&dev_list_lock);
1865                 schedule_timeout(round_jiffies_relative(HZ));
1866         }
1867         return 0;
1868 }
1869
1870 static void nvme_config_discard(struct nvme_ns *ns)
1871 {
1872         u32 logical_block_size = queue_logical_block_size(ns->queue);
1873         ns->queue->limits.discard_zeroes_data = 0;
1874         ns->queue->limits.discard_alignment = logical_block_size;
1875         ns->queue->limits.discard_granularity = logical_block_size;
1876         ns->queue->limits.max_discard_sectors = 0xffffffff;
1877         queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, ns->queue);
1878 }
1879
1880 static struct nvme_ns *nvme_alloc_ns(struct nvme_dev *dev, unsigned nsid,
1881                         struct nvme_id_ns *id, struct nvme_lba_range_type *rt)
1882 {
1883         struct nvme_ns *ns;
1884         struct gendisk *disk;
1885         int node = dev_to_node(&dev->pci_dev->dev);
1886         int lbaf;
1887
1888         if (rt->attributes & NVME_LBART_ATTRIB_HIDE)
1889                 return NULL;
1890
1891         ns = kzalloc_node(sizeof(*ns), GFP_KERNEL, node);
1892         if (!ns)
1893                 return NULL;
1894         ns->queue = blk_mq_init_queue(&dev->tagset);
1895         if (IS_ERR(ns->queue))
1896                 goto out_free_ns;
1897         queue_flag_set_unlocked(QUEUE_FLAG_NOMERGES, ns->queue);
1898         queue_flag_set_unlocked(QUEUE_FLAG_NONROT, ns->queue);
1899         queue_flag_set_unlocked(QUEUE_FLAG_SG_GAPS, ns->queue);
1900         ns->dev = dev;
1901         ns->queue->queuedata = ns;
1902
1903         disk = alloc_disk_node(0, node);
1904         if (!disk)
1905                 goto out_free_queue;
1906
1907         ns->ns_id = nsid;
1908         ns->disk = disk;
1909         lbaf = id->flbas & 0xf;
1910         ns->lba_shift = id->lbaf[lbaf].ds;
1911         ns->ms = le16_to_cpu(id->lbaf[lbaf].ms);
1912         blk_queue_logical_block_size(ns->queue, 1 << ns->lba_shift);
1913         if (dev->max_hw_sectors)
1914                 blk_queue_max_hw_sectors(ns->queue, dev->max_hw_sectors);
1915         if (dev->stripe_size)
1916                 blk_queue_chunk_sectors(ns->queue, dev->stripe_size >> 9);
1917         if (dev->vwc & NVME_CTRL_VWC_PRESENT)
1918                 blk_queue_flush(ns->queue, REQ_FLUSH | REQ_FUA);
1919
1920         disk->major = nvme_major;
1921         disk->first_minor = 0;
1922         disk->fops = &nvme_fops;
1923         disk->private_data = ns;
1924         disk->queue = ns->queue;
1925         disk->driverfs_dev = &dev->pci_dev->dev;
1926         disk->flags = GENHD_FL_EXT_DEVT;
1927         sprintf(disk->disk_name, "nvme%dn%d", dev->instance, nsid);
1928         set_capacity(disk, le64_to_cpup(&id->nsze) << (ns->lba_shift - 9));
1929
1930         if (dev->oncs & NVME_CTRL_ONCS_DSM)
1931                 nvme_config_discard(ns);
1932
1933         return ns;
1934
1935  out_free_queue:
1936         blk_cleanup_queue(ns->queue);
1937  out_free_ns:
1938         kfree(ns);
1939         return NULL;
1940 }
1941
1942 static void nvme_create_io_queues(struct nvme_dev *dev)
1943 {
1944         unsigned i;
1945
1946         for (i = dev->queue_count; i <= dev->max_qid; i++)
1947                 if (!nvme_alloc_queue(dev, i, dev->q_depth, i - 1))
1948                         break;
1949
1950         for (i = dev->online_queues; i <= dev->queue_count - 1; i++)
1951                 if (nvme_create_queue(dev->queues[i], i))
1952                         break;
1953 }
1954
1955 static int set_queue_count(struct nvme_dev *dev, int count)
1956 {
1957         int status;
1958         u32 result;
1959         u32 q_count = (count - 1) | ((count - 1) << 16);
1960
1961         status = nvme_set_features(dev, NVME_FEAT_NUM_QUEUES, q_count, 0,
1962                                                                 &result);
1963         if (status < 0)
1964                 return status;
1965         if (status > 0) {
1966                 dev_err(&dev->pci_dev->dev, "Could not set queue count (%d)\n",
1967                                                                         status);
1968                 return 0;
1969         }
1970         return min(result & 0xffff, result >> 16) + 1;
1971 }
1972
1973 static size_t db_bar_size(struct nvme_dev *dev, unsigned nr_io_queues)
1974 {
1975         return 4096 + ((nr_io_queues + 1) * 8 * dev->db_stride);
1976 }
1977
1978 static int nvme_setup_io_queues(struct nvme_dev *dev)
1979 {
1980         struct nvme_queue *adminq = dev->queues[0];
1981         struct pci_dev *pdev = dev->pci_dev;
1982         int result, i, vecs, nr_io_queues, size;
1983
1984         nr_io_queues = num_possible_cpus();
1985         result = set_queue_count(dev, nr_io_queues);
1986         if (result <= 0)
1987                 return result;
1988         if (result < nr_io_queues)
1989                 nr_io_queues = result;
1990
1991         size = db_bar_size(dev, nr_io_queues);
1992         if (size > 8192) {
1993                 iounmap(dev->bar);
1994                 do {
1995                         dev->bar = ioremap(pci_resource_start(pdev, 0), size);
1996                         if (dev->bar)
1997                                 break;
1998                         if (!--nr_io_queues)
1999                                 return -ENOMEM;
2000                         size = db_bar_size(dev, nr_io_queues);
2001                 } while (1);
2002                 dev->dbs = ((void __iomem *)dev->bar) + 4096;
2003                 adminq->q_db = dev->dbs;
2004         }
2005
2006         /* Deregister the admin queue's interrupt */
2007         free_irq(dev->entry[0].vector, adminq);
2008
2009         /*
2010          * If we enable msix early due to not intx, disable it again before
2011          * setting up the full range we need.
2012          */
2013         if (!pdev->irq)
2014                 pci_disable_msix(pdev);
2015
2016         for (i = 0; i < nr_io_queues; i++)
2017                 dev->entry[i].entry = i;
2018         vecs = pci_enable_msix_range(pdev, dev->entry, 1, nr_io_queues);
2019         if (vecs < 0) {
2020                 vecs = pci_enable_msi_range(pdev, 1, min(nr_io_queues, 32));
2021                 if (vecs < 0) {
2022                         vecs = 1;
2023                 } else {
2024                         for (i = 0; i < vecs; i++)
2025                                 dev->entry[i].vector = i + pdev->irq;
2026                 }
2027         }
2028
2029         /*
2030          * Should investigate if there's a performance win from allocating
2031          * more queues than interrupt vectors; it might allow the submission
2032          * path to scale better, even if the receive path is limited by the
2033          * number of interrupts.
2034          */
2035         nr_io_queues = vecs;
2036         dev->max_qid = nr_io_queues;
2037
2038         result = queue_request_irq(dev, adminq, adminq->irqname);
2039         if (result)
2040                 goto free_queues;
2041
2042         /* Free previously allocated queues that are no longer usable */
2043         nvme_free_queues(dev, nr_io_queues + 1);
2044         nvme_create_io_queues(dev);
2045
2046         return 0;
2047
2048  free_queues:
2049         nvme_free_queues(dev, 1);
2050         return result;
2051 }
2052
2053 /*
2054  * Return: error value if an error occurred setting up the queues or calling
2055  * Identify Device.  0 if these succeeded, even if adding some of the
2056  * namespaces failed.  At the moment, these failures are silent.  TBD which
2057  * failures should be reported.
2058  */
2059 static int nvme_dev_add(struct nvme_dev *dev)
2060 {
2061         struct pci_dev *pdev = dev->pci_dev;
2062         int res;
2063         unsigned nn, i;
2064         struct nvme_ns *ns;
2065         struct nvme_id_ctrl *ctrl;
2066         struct nvme_id_ns *id_ns;
2067         void *mem;
2068         dma_addr_t dma_addr;
2069         int shift = NVME_CAP_MPSMIN(readq(&dev->bar->cap)) + 12;
2070
2071         mem = dma_alloc_coherent(&pdev->dev, 8192, &dma_addr, GFP_KERNEL);
2072         if (!mem)
2073                 return -ENOMEM;
2074
2075         res = nvme_identify(dev, 0, 1, dma_addr);
2076         if (res) {
2077                 dev_err(&pdev->dev, "Identify Controller failed (%d)\n", res);
2078                 res = -EIO;
2079                 goto out;
2080         }
2081
2082         ctrl = mem;
2083         nn = le32_to_cpup(&ctrl->nn);
2084         dev->oncs = le16_to_cpup(&ctrl->oncs);
2085         dev->abort_limit = ctrl->acl + 1;
2086         dev->vwc = ctrl->vwc;
2087         dev->event_limit = min(ctrl->aerl + 1, 8);
2088         memcpy(dev->serial, ctrl->sn, sizeof(ctrl->sn));
2089         memcpy(dev->model, ctrl->mn, sizeof(ctrl->mn));
2090         memcpy(dev->firmware_rev, ctrl->fr, sizeof(ctrl->fr));
2091         if (ctrl->mdts)
2092                 dev->max_hw_sectors = 1 << (ctrl->mdts + shift - 9);
2093         if ((pdev->vendor == PCI_VENDOR_ID_INTEL) &&
2094                         (pdev->device == 0x0953) && ctrl->vs[3]) {
2095                 unsigned int max_hw_sectors;
2096
2097                 dev->stripe_size = 1 << (ctrl->vs[3] + shift);
2098                 max_hw_sectors = dev->stripe_size >> (shift - 9);
2099                 if (dev->max_hw_sectors) {
2100                         dev->max_hw_sectors = min(max_hw_sectors,
2101                                                         dev->max_hw_sectors);
2102                 } else
2103                         dev->max_hw_sectors = max_hw_sectors;
2104         }
2105
2106         dev->tagset.ops = &nvme_mq_ops;
2107         dev->tagset.nr_hw_queues = dev->online_queues - 1;
2108         dev->tagset.timeout = NVME_IO_TIMEOUT;
2109         dev->tagset.numa_node = dev_to_node(&dev->pci_dev->dev);
2110         dev->tagset.queue_depth =
2111                                 min_t(int, dev->q_depth, BLK_MQ_MAX_DEPTH) - 1;
2112         dev->tagset.cmd_size = sizeof(struct nvme_cmd_info);
2113         dev->tagset.flags = BLK_MQ_F_SHOULD_MERGE;
2114         dev->tagset.driver_data = dev;
2115
2116         if (blk_mq_alloc_tag_set(&dev->tagset))
2117                 goto out;
2118
2119         id_ns = mem;
2120         for (i = 1; i <= nn; i++) {
2121                 res = nvme_identify(dev, i, 0, dma_addr);
2122                 if (res)
2123                         continue;
2124
2125                 if (id_ns->ncap == 0)
2126                         continue;
2127
2128                 res = nvme_get_features(dev, NVME_FEAT_LBA_RANGE, i,
2129                                                         dma_addr + 4096, NULL);
2130                 if (res)
2131                         memset(mem + 4096, 0, 4096);
2132
2133                 ns = nvme_alloc_ns(dev, i, mem, mem + 4096);
2134                 if (ns)
2135                         list_add_tail(&ns->list, &dev->namespaces);
2136         }
2137         list_for_each_entry(ns, &dev->namespaces, list)
2138                 add_disk(ns->disk);
2139         res = 0;
2140
2141  out:
2142         dma_free_coherent(&dev->pci_dev->dev, 8192, mem, dma_addr);
2143         return res;
2144 }
2145
2146 static int nvme_dev_map(struct nvme_dev *dev)
2147 {
2148         u64 cap;
2149         int bars, result = -ENOMEM;
2150         struct pci_dev *pdev = dev->pci_dev;
2151
2152         if (pci_enable_device_mem(pdev))
2153                 return result;
2154
2155         dev->entry[0].vector = pdev->irq;
2156         pci_set_master(pdev);
2157         bars = pci_select_bars(pdev, IORESOURCE_MEM);
2158         if (!bars)
2159                 goto disable_pci;
2160
2161         if (pci_request_selected_regions(pdev, bars, "nvme"))
2162                 goto disable_pci;
2163
2164         if (dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)) &&
2165             dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)))
2166                 goto disable;
2167
2168         dev->bar = ioremap(pci_resource_start(pdev, 0), 8192);
2169         if (!dev->bar)
2170                 goto disable;
2171
2172         if (readl(&dev->bar->csts) == -1) {
2173                 result = -ENODEV;
2174                 goto unmap;
2175         }
2176
2177         /*
2178          * Some devices don't advertse INTx interrupts, pre-enable a single
2179          * MSIX vec for setup. We'll adjust this later.
2180          */
2181         if (!pdev->irq) {
2182                 result = pci_enable_msix(pdev, dev->entry, 1);
2183                 if (result < 0)
2184                         goto unmap;
2185         }
2186
2187         cap = readq(&dev->bar->cap);
2188         dev->q_depth = min_t(int, NVME_CAP_MQES(cap) + 1, NVME_Q_DEPTH);
2189         dev->db_stride = 1 << NVME_CAP_STRIDE(cap);
2190         dev->dbs = ((void __iomem *)dev->bar) + 4096;
2191
2192         return 0;
2193
2194  unmap:
2195         iounmap(dev->bar);
2196         dev->bar = NULL;
2197  disable:
2198         pci_release_regions(pdev);
2199  disable_pci:
2200         pci_disable_device(pdev);
2201         return result;
2202 }
2203
2204 static void nvme_dev_unmap(struct nvme_dev *dev)
2205 {
2206         if (dev->pci_dev->msi_enabled)
2207                 pci_disable_msi(dev->pci_dev);
2208         else if (dev->pci_dev->msix_enabled)
2209                 pci_disable_msix(dev->pci_dev);
2210
2211         if (dev->bar) {
2212                 iounmap(dev->bar);
2213                 dev->bar = NULL;
2214                 pci_release_regions(dev->pci_dev);
2215         }
2216
2217         if (pci_is_enabled(dev->pci_dev))
2218                 pci_disable_device(dev->pci_dev);
2219 }
2220
2221 struct nvme_delq_ctx {
2222         struct task_struct *waiter;
2223         struct kthread_worker *worker;
2224         atomic_t refcount;
2225 };
2226
2227 static void nvme_wait_dq(struct nvme_delq_ctx *dq, struct nvme_dev *dev)
2228 {
2229         dq->waiter = current;
2230         mb();
2231
2232         for (;;) {
2233                 set_current_state(TASK_KILLABLE);
2234                 if (!atomic_read(&dq->refcount))
2235                         break;
2236                 if (!schedule_timeout(ADMIN_TIMEOUT) ||
2237                                         fatal_signal_pending(current)) {
2238                         set_current_state(TASK_RUNNING);
2239
2240                         nvme_disable_ctrl(dev, readq(&dev->bar->cap));
2241                         nvme_disable_queue(dev, 0);
2242
2243                         send_sig(SIGKILL, dq->worker->task, 1);
2244                         flush_kthread_worker(dq->worker);
2245                         return;
2246                 }
2247         }
2248         set_current_state(TASK_RUNNING);
2249 }
2250
2251 static void nvme_put_dq(struct nvme_delq_ctx *dq)
2252 {
2253         atomic_dec(&dq->refcount);
2254         if (dq->waiter)
2255                 wake_up_process(dq->waiter);
2256 }
2257
2258 static struct nvme_delq_ctx *nvme_get_dq(struct nvme_delq_ctx *dq)
2259 {
2260         atomic_inc(&dq->refcount);
2261         return dq;
2262 }
2263
2264 static void nvme_del_queue_end(struct nvme_queue *nvmeq)
2265 {
2266         struct nvme_delq_ctx *dq = nvmeq->cmdinfo.ctx;
2267
2268         nvme_clear_queue(nvmeq);
2269         nvme_put_dq(dq);
2270 }
2271
2272 static int adapter_async_del_queue(struct nvme_queue *nvmeq, u8 opcode,
2273                                                 kthread_work_func_t fn)
2274 {
2275         struct nvme_command c;
2276
2277         memset(&c, 0, sizeof(c));
2278         c.delete_queue.opcode = opcode;
2279         c.delete_queue.qid = cpu_to_le16(nvmeq->qid);
2280
2281         init_kthread_work(&nvmeq->cmdinfo.work, fn);
2282         return nvme_submit_admin_async_cmd(nvmeq->dev, &c, &nvmeq->cmdinfo,
2283                                                                 ADMIN_TIMEOUT);
2284 }
2285
2286 static void nvme_del_cq_work_handler(struct kthread_work *work)
2287 {
2288         struct nvme_queue *nvmeq = container_of(work, struct nvme_queue,
2289                                                         cmdinfo.work);
2290         nvme_del_queue_end(nvmeq);
2291 }
2292
2293 static int nvme_delete_cq(struct nvme_queue *nvmeq)
2294 {
2295         return adapter_async_del_queue(nvmeq, nvme_admin_delete_cq,
2296                                                 nvme_del_cq_work_handler);
2297 }
2298
2299 static void nvme_del_sq_work_handler(struct kthread_work *work)
2300 {
2301         struct nvme_queue *nvmeq = container_of(work, struct nvme_queue,
2302                                                         cmdinfo.work);
2303         int status = nvmeq->cmdinfo.status;
2304
2305         if (!status)
2306                 status = nvme_delete_cq(nvmeq);
2307         if (status)
2308                 nvme_del_queue_end(nvmeq);
2309 }
2310
2311 static int nvme_delete_sq(struct nvme_queue *nvmeq)
2312 {
2313         return adapter_async_del_queue(nvmeq, nvme_admin_delete_sq,
2314                                                 nvme_del_sq_work_handler);
2315 }
2316
2317 static void nvme_del_queue_start(struct kthread_work *work)
2318 {
2319         struct nvme_queue *nvmeq = container_of(work, struct nvme_queue,
2320                                                         cmdinfo.work);
2321         allow_signal(SIGKILL);
2322         if (nvme_delete_sq(nvmeq))
2323                 nvme_del_queue_end(nvmeq);
2324 }
2325
2326 static void nvme_disable_io_queues(struct nvme_dev *dev)
2327 {
2328         int i;
2329         DEFINE_KTHREAD_WORKER_ONSTACK(worker);
2330         struct nvme_delq_ctx dq;
2331         struct task_struct *kworker_task = kthread_run(kthread_worker_fn,
2332                                         &worker, "nvme%d", dev->instance);
2333
2334         if (IS_ERR(kworker_task)) {
2335                 dev_err(&dev->pci_dev->dev,
2336                         "Failed to create queue del task\n");
2337                 for (i = dev->queue_count - 1; i > 0; i--)
2338                         nvme_disable_queue(dev, i);
2339                 return;
2340         }
2341
2342         dq.waiter = NULL;
2343         atomic_set(&dq.refcount, 0);
2344         dq.worker = &worker;
2345         for (i = dev->queue_count - 1; i > 0; i--) {
2346                 struct nvme_queue *nvmeq = dev->queues[i];
2347
2348                 if (nvme_suspend_queue(nvmeq))
2349                         continue;
2350                 nvmeq->cmdinfo.ctx = nvme_get_dq(&dq);
2351                 nvmeq->cmdinfo.worker = dq.worker;
2352                 init_kthread_work(&nvmeq->cmdinfo.work, nvme_del_queue_start);
2353                 queue_kthread_work(dq.worker, &nvmeq->cmdinfo.work);
2354         }
2355         nvme_wait_dq(&dq, dev);
2356         kthread_stop(kworker_task);
2357 }
2358
2359 /*
2360 * Remove the node from the device list and check
2361 * for whether or not we need to stop the nvme_thread.
2362 */
2363 static void nvme_dev_list_remove(struct nvme_dev *dev)
2364 {
2365         struct task_struct *tmp = NULL;
2366
2367         spin_lock(&dev_list_lock);
2368         list_del_init(&dev->node);
2369         if (list_empty(&dev_list) && !IS_ERR_OR_NULL(nvme_thread)) {
2370                 tmp = nvme_thread;
2371                 nvme_thread = NULL;
2372         }
2373         spin_unlock(&dev_list_lock);
2374
2375         if (tmp)
2376                 kthread_stop(tmp);
2377 }
2378
2379 static void nvme_dev_shutdown(struct nvme_dev *dev)
2380 {
2381         int i;
2382         u32 csts = -1;
2383
2384         dev->initialized = 0;
2385         nvme_dev_list_remove(dev);
2386
2387         if (dev->bar)
2388                 csts = readl(&dev->bar->csts);
2389         if (csts & NVME_CSTS_CFS || !(csts & NVME_CSTS_RDY)) {
2390                 for (i = dev->queue_count - 1; i >= 0; i--) {
2391                         struct nvme_queue *nvmeq = dev->queues[i];
2392                         nvme_suspend_queue(nvmeq);
2393                         nvme_clear_queue(nvmeq);
2394                 }
2395         } else {
2396                 nvme_disable_io_queues(dev);
2397                 nvme_shutdown_ctrl(dev);
2398                 nvme_disable_queue(dev, 0);
2399         }
2400         nvme_dev_unmap(dev);
2401 }
2402
2403 static void nvme_dev_remove_admin(struct nvme_dev *dev)
2404 {
2405         if (dev->admin_q && !blk_queue_dying(dev->admin_q))
2406                 blk_cleanup_queue(dev->admin_q);
2407 }
2408
2409 static void nvme_dev_remove(struct nvme_dev *dev)
2410 {
2411         struct nvme_ns *ns;
2412
2413         list_for_each_entry(ns, &dev->namespaces, list) {
2414                 if (ns->disk->flags & GENHD_FL_UP)
2415                         del_gendisk(ns->disk);
2416                 if (!blk_queue_dying(ns->queue))
2417                         blk_cleanup_queue(ns->queue);
2418         }
2419 }
2420
2421 static int nvme_setup_prp_pools(struct nvme_dev *dev)
2422 {
2423         struct device *dmadev = &dev->pci_dev->dev;
2424         dev->prp_page_pool = dma_pool_create("prp list page", dmadev,
2425                                                 PAGE_SIZE, PAGE_SIZE, 0);
2426         if (!dev->prp_page_pool)
2427                 return -ENOMEM;
2428
2429         /* Optimisation for I/Os between 4k and 128k */
2430         dev->prp_small_pool = dma_pool_create("prp list 256", dmadev,
2431                                                 256, 256, 0);
2432         if (!dev->prp_small_pool) {
2433                 dma_pool_destroy(dev->prp_page_pool);
2434                 return -ENOMEM;
2435         }
2436         return 0;
2437 }
2438
2439 static void nvme_release_prp_pools(struct nvme_dev *dev)
2440 {
2441         dma_pool_destroy(dev->prp_page_pool);
2442         dma_pool_destroy(dev->prp_small_pool);
2443 }
2444
2445 static DEFINE_IDA(nvme_instance_ida);
2446
2447 static int nvme_set_instance(struct nvme_dev *dev)
2448 {
2449         int instance, error;
2450
2451         do {
2452                 if (!ida_pre_get(&nvme_instance_ida, GFP_KERNEL))
2453                         return -ENODEV;
2454
2455                 spin_lock(&dev_list_lock);
2456                 error = ida_get_new(&nvme_instance_ida, &instance);
2457                 spin_unlock(&dev_list_lock);
2458         } while (error == -EAGAIN);
2459
2460         if (error)
2461                 return -ENODEV;
2462
2463         dev->instance = instance;
2464         return 0;
2465 }
2466
2467 static void nvme_release_instance(struct nvme_dev *dev)
2468 {
2469         spin_lock(&dev_list_lock);
2470         ida_remove(&nvme_instance_ida, dev->instance);
2471         spin_unlock(&dev_list_lock);
2472 }
2473
2474 static void nvme_free_namespaces(struct nvme_dev *dev)
2475 {
2476         struct nvme_ns *ns, *next;
2477
2478         list_for_each_entry_safe(ns, next, &dev->namespaces, list) {
2479                 list_del(&ns->list);
2480
2481                 spin_lock(&dev_list_lock);
2482                 ns->disk->private_data = NULL;
2483                 spin_unlock(&dev_list_lock);
2484
2485                 put_disk(ns->disk);
2486                 kfree(ns);
2487         }
2488 }
2489
2490 static void nvme_free_dev(struct kref *kref)
2491 {
2492         struct nvme_dev *dev = container_of(kref, struct nvme_dev, kref);
2493
2494         pci_dev_put(dev->pci_dev);
2495         nvme_free_namespaces(dev);
2496         nvme_release_instance(dev);
2497         blk_mq_free_tag_set(&dev->tagset);
2498         kfree(dev->queues);
2499         kfree(dev->entry);
2500         kfree(dev);
2501 }
2502
2503 static int nvme_dev_open(struct inode *inode, struct file *f)
2504 {
2505         struct nvme_dev *dev = container_of(f->private_data, struct nvme_dev,
2506                                                                 miscdev);
2507         kref_get(&dev->kref);
2508         f->private_data = dev;
2509         return 0;
2510 }
2511
2512 static int nvme_dev_release(struct inode *inode, struct file *f)
2513 {
2514         struct nvme_dev *dev = f->private_data;
2515         kref_put(&dev->kref, nvme_free_dev);
2516         return 0;
2517 }
2518
2519 static long nvme_dev_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
2520 {
2521         struct nvme_dev *dev = f->private_data;
2522         struct nvme_ns *ns;
2523
2524         switch (cmd) {
2525         case NVME_IOCTL_ADMIN_CMD:
2526                 return nvme_user_cmd(dev, NULL, (void __user *)arg);
2527         case NVME_IOCTL_IO_CMD:
2528                 if (list_empty(&dev->namespaces))
2529                         return -ENOTTY;
2530                 ns = list_first_entry(&dev->namespaces, struct nvme_ns, list);
2531                 return nvme_user_cmd(dev, ns, (void __user *)arg);
2532         default:
2533                 return -ENOTTY;
2534         }
2535 }
2536
2537 static const struct file_operations nvme_dev_fops = {
2538         .owner          = THIS_MODULE,
2539         .open           = nvme_dev_open,
2540         .release        = nvme_dev_release,
2541         .unlocked_ioctl = nvme_dev_ioctl,
2542         .compat_ioctl   = nvme_dev_ioctl,
2543 };
2544
2545 static void nvme_set_irq_hints(struct nvme_dev *dev)
2546 {
2547         struct nvme_queue *nvmeq;
2548         int i;
2549
2550         for (i = 0; i < dev->online_queues; i++) {
2551                 nvmeq = dev->queues[i];
2552
2553                 if (!nvmeq->hctx)
2554                         continue;
2555
2556                 irq_set_affinity_hint(dev->entry[nvmeq->cq_vector].vector,
2557                                                         nvmeq->hctx->cpumask);
2558         }
2559 }
2560
2561 static int nvme_dev_start(struct nvme_dev *dev)
2562 {
2563         int result;
2564         bool start_thread = false;
2565
2566         result = nvme_dev_map(dev);
2567         if (result)
2568                 return result;
2569
2570         result = nvme_configure_admin_queue(dev);
2571         if (result)
2572                 goto unmap;
2573
2574         spin_lock(&dev_list_lock);
2575         if (list_empty(&dev_list) && IS_ERR_OR_NULL(nvme_thread)) {
2576                 start_thread = true;
2577                 nvme_thread = NULL;
2578         }
2579         list_add(&dev->node, &dev_list);
2580         spin_unlock(&dev_list_lock);
2581
2582         if (start_thread) {
2583                 nvme_thread = kthread_run(nvme_kthread, NULL, "nvme");
2584                 wake_up_all(&nvme_kthread_wait);
2585         } else
2586                 wait_event_killable(nvme_kthread_wait, nvme_thread);
2587
2588         if (IS_ERR_OR_NULL(nvme_thread)) {
2589                 result = nvme_thread ? PTR_ERR(nvme_thread) : -EINTR;
2590                 goto disable;
2591         }
2592
2593         nvme_init_queue(dev->queues[0], 0);
2594
2595         result = nvme_setup_io_queues(dev);
2596         if (result)
2597                 goto disable;
2598
2599         nvme_set_irq_hints(dev);
2600
2601         return result;
2602
2603  disable:
2604         nvme_disable_queue(dev, 0);
2605         nvme_dev_list_remove(dev);
2606  unmap:
2607         nvme_dev_unmap(dev);
2608         return result;
2609 }
2610
2611 static int nvme_remove_dead_ctrl(void *arg)
2612 {
2613         struct nvme_dev *dev = (struct nvme_dev *)arg;
2614         struct pci_dev *pdev = dev->pci_dev;
2615
2616         if (pci_get_drvdata(pdev))
2617                 pci_stop_and_remove_bus_device_locked(pdev);
2618         kref_put(&dev->kref, nvme_free_dev);
2619         return 0;
2620 }
2621
2622 static void nvme_remove_disks(struct work_struct *ws)
2623 {
2624         struct nvme_dev *dev = container_of(ws, struct nvme_dev, reset_work);
2625
2626         nvme_free_queues(dev, 1);
2627         nvme_dev_remove(dev);
2628 }
2629
2630 static int nvme_dev_resume(struct nvme_dev *dev)
2631 {
2632         int ret;
2633
2634         ret = nvme_dev_start(dev);
2635         if (ret)
2636                 return ret;
2637         if (dev->online_queues < 2) {
2638                 spin_lock(&dev_list_lock);
2639                 dev->reset_workfn = nvme_remove_disks;
2640                 queue_work(nvme_workq, &dev->reset_work);
2641                 spin_unlock(&dev_list_lock);
2642         }
2643         dev->initialized = 1;
2644         return 0;
2645 }
2646
2647 static void nvme_dev_reset(struct nvme_dev *dev)
2648 {
2649         nvme_dev_shutdown(dev);
2650         if (nvme_dev_resume(dev)) {
2651                 dev_warn(&dev->pci_dev->dev, "Device failed to resume\n");
2652                 kref_get(&dev->kref);
2653                 if (IS_ERR(kthread_run(nvme_remove_dead_ctrl, dev, "nvme%d",
2654                                                         dev->instance))) {
2655                         dev_err(&dev->pci_dev->dev,
2656                                 "Failed to start controller remove task\n");
2657                         kref_put(&dev->kref, nvme_free_dev);
2658                 }
2659         }
2660 }
2661
2662 static void nvme_reset_failed_dev(struct work_struct *ws)
2663 {
2664         struct nvme_dev *dev = container_of(ws, struct nvme_dev, reset_work);
2665         nvme_dev_reset(dev);
2666 }
2667
2668 static void nvme_reset_workfn(struct work_struct *work)
2669 {
2670         struct nvme_dev *dev = container_of(work, struct nvme_dev, reset_work);
2671         dev->reset_workfn(work);
2672 }
2673
2674 static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
2675 {
2676         int node, result = -ENOMEM;
2677         struct nvme_dev *dev;
2678
2679         node = dev_to_node(&pdev->dev);
2680         if (node == NUMA_NO_NODE)
2681                 set_dev_node(&pdev->dev, 0);
2682
2683         dev = kzalloc_node(sizeof(*dev), GFP_KERNEL, node);
2684         if (!dev)
2685                 return -ENOMEM;
2686         dev->entry = kzalloc_node(num_possible_cpus() * sizeof(*dev->entry),
2687                                                         GFP_KERNEL, node);
2688         if (!dev->entry)
2689                 goto free;
2690         dev->queues = kzalloc_node((num_possible_cpus() + 1) * sizeof(void *),
2691                                                         GFP_KERNEL, node);
2692         if (!dev->queues)
2693                 goto free;
2694
2695         INIT_LIST_HEAD(&dev->namespaces);
2696         dev->reset_workfn = nvme_reset_failed_dev;
2697         INIT_WORK(&dev->reset_work, nvme_reset_workfn);
2698         dev->pci_dev = pci_dev_get(pdev);
2699         pci_set_drvdata(pdev, dev);
2700         result = nvme_set_instance(dev);
2701         if (result)
2702                 goto put_pci;
2703
2704         result = nvme_setup_prp_pools(dev);
2705         if (result)
2706                 goto release;
2707
2708         kref_init(&dev->kref);
2709         result = nvme_dev_start(dev);
2710         if (result)
2711                 goto release_pools;
2712
2713         if (dev->online_queues > 1)
2714                 result = nvme_dev_add(dev);
2715         if (result)
2716                 goto shutdown;
2717
2718         scnprintf(dev->name, sizeof(dev->name), "nvme%d", dev->instance);
2719         dev->miscdev.minor = MISC_DYNAMIC_MINOR;
2720         dev->miscdev.parent = &pdev->dev;
2721         dev->miscdev.name = dev->name;
2722         dev->miscdev.fops = &nvme_dev_fops;
2723         result = misc_register(&dev->miscdev);
2724         if (result)
2725                 goto remove;
2726
2727         nvme_set_irq_hints(dev);
2728
2729         dev->initialized = 1;
2730         return 0;
2731
2732  remove:
2733         nvme_dev_remove(dev);
2734         nvme_dev_remove_admin(dev);
2735         nvme_free_namespaces(dev);
2736  shutdown:
2737         nvme_dev_shutdown(dev);
2738  release_pools:
2739         nvme_free_queues(dev, 0);
2740         nvme_release_prp_pools(dev);
2741  release:
2742         nvme_release_instance(dev);
2743  put_pci:
2744         pci_dev_put(dev->pci_dev);
2745  free:
2746         kfree(dev->queues);
2747         kfree(dev->entry);
2748         kfree(dev);
2749         return result;
2750 }
2751
2752 static void nvme_reset_notify(struct pci_dev *pdev, bool prepare)
2753 {
2754         struct nvme_dev *dev = pci_get_drvdata(pdev);
2755
2756         if (prepare)
2757                 nvme_dev_shutdown(dev);
2758         else
2759                 nvme_dev_resume(dev);
2760 }
2761
2762 static void nvme_shutdown(struct pci_dev *pdev)
2763 {
2764         struct nvme_dev *dev = pci_get_drvdata(pdev);
2765         nvme_dev_shutdown(dev);
2766 }
2767
2768 static void nvme_remove(struct pci_dev *pdev)
2769 {
2770         struct nvme_dev *dev = pci_get_drvdata(pdev);
2771
2772         spin_lock(&dev_list_lock);
2773         list_del_init(&dev->node);
2774         spin_unlock(&dev_list_lock);
2775
2776         pci_set_drvdata(pdev, NULL);
2777         flush_work(&dev->reset_work);
2778         misc_deregister(&dev->miscdev);
2779         nvme_dev_remove(dev);
2780         nvme_dev_shutdown(dev);
2781         nvme_dev_remove_admin(dev);
2782         nvme_free_queues(dev, 0);
2783         nvme_free_admin_tags(dev);
2784         nvme_release_prp_pools(dev);
2785         kref_put(&dev->kref, nvme_free_dev);
2786 }
2787
2788 /* These functions are yet to be implemented */
2789 #define nvme_error_detected NULL
2790 #define nvme_dump_registers NULL
2791 #define nvme_link_reset NULL
2792 #define nvme_slot_reset NULL
2793 #define nvme_error_resume NULL
2794
2795 #ifdef CONFIG_PM_SLEEP
2796 static int nvme_suspend(struct device *dev)
2797 {
2798         struct pci_dev *pdev = to_pci_dev(dev);
2799         struct nvme_dev *ndev = pci_get_drvdata(pdev);
2800
2801         nvme_dev_shutdown(ndev);
2802         return 0;
2803 }
2804
2805 static int nvme_resume(struct device *dev)
2806 {
2807         struct pci_dev *pdev = to_pci_dev(dev);
2808         struct nvme_dev *ndev = pci_get_drvdata(pdev);
2809
2810         if (nvme_dev_resume(ndev) && !work_busy(&ndev->reset_work)) {
2811                 ndev->reset_workfn = nvme_reset_failed_dev;
2812                 queue_work(nvme_workq, &ndev->reset_work);
2813         }
2814         return 0;
2815 }
2816 #endif
2817
2818 static SIMPLE_DEV_PM_OPS(nvme_dev_pm_ops, nvme_suspend, nvme_resume);
2819
2820 static const struct pci_error_handlers nvme_err_handler = {
2821         .error_detected = nvme_error_detected,
2822         .mmio_enabled   = nvme_dump_registers,
2823         .link_reset     = nvme_link_reset,
2824         .slot_reset     = nvme_slot_reset,
2825         .resume         = nvme_error_resume,
2826         .reset_notify   = nvme_reset_notify,
2827 };
2828
2829 /* Move to pci_ids.h later */
2830 #define PCI_CLASS_STORAGE_EXPRESS       0x010802
2831
2832 static const struct pci_device_id nvme_id_table[] = {
2833         { PCI_DEVICE_CLASS(PCI_CLASS_STORAGE_EXPRESS, 0xffffff) },
2834         { 0, }
2835 };
2836 MODULE_DEVICE_TABLE(pci, nvme_id_table);
2837
2838 static struct pci_driver nvme_driver = {
2839         .name           = "nvme",
2840         .id_table       = nvme_id_table,
2841         .probe          = nvme_probe,
2842         .remove         = nvme_remove,
2843         .shutdown       = nvme_shutdown,
2844         .driver         = {
2845                 .pm     = &nvme_dev_pm_ops,
2846         },
2847         .err_handler    = &nvme_err_handler,
2848 };
2849
2850 static int __init nvme_init(void)
2851 {
2852         int result;
2853
2854         init_waitqueue_head(&nvme_kthread_wait);
2855
2856         nvme_workq = create_singlethread_workqueue("nvme");
2857         if (!nvme_workq)
2858                 return -ENOMEM;
2859
2860         result = register_blkdev(nvme_major, "nvme");
2861         if (result < 0)
2862                 goto kill_workq;
2863         else if (result > 0)
2864                 nvme_major = result;
2865
2866         result = pci_register_driver(&nvme_driver);
2867         if (result)
2868                 goto unregister_blkdev;
2869         return 0;
2870
2871  unregister_blkdev:
2872         unregister_blkdev(nvme_major, "nvme");
2873  kill_workq:
2874         destroy_workqueue(nvme_workq);
2875         return result;
2876 }
2877
2878 static void __exit nvme_exit(void)
2879 {
2880         pci_unregister_driver(&nvme_driver);
2881         unregister_hotcpu_notifier(&nvme_nb);
2882         unregister_blkdev(nvme_major, "nvme");
2883         destroy_workqueue(nvme_workq);
2884         BUG_ON(nvme_thread && !IS_ERR(nvme_thread));
2885         _nvme_check_size();
2886 }
2887
2888 MODULE_AUTHOR("Matthew Wilcox <willy@linux.intel.com>");
2889 MODULE_LICENSE("GPL");
2890 MODULE_VERSION("1.0");
2891 module_init(nvme_init);
2892 module_exit(nvme_exit);