Commit | Line | Data |
---|---|---|
f2298c04 | 1 | #include <linux/module.h> |
fc1bc354 | 2 | |
f2298c04 JA |
3 | #include <linux/moduleparam.h> |
4 | #include <linux/sched.h> | |
5 | #include <linux/fs.h> | |
6 | #include <linux/blkdev.h> | |
7 | #include <linux/init.h> | |
8 | #include <linux/slab.h> | |
9 | #include <linux/blk-mq.h> | |
10 | #include <linux/hrtimer.h> | |
11 | ||
12 | struct nullb_cmd { | |
13 | struct list_head list; | |
14 | struct llist_node ll_list; | |
15 | struct call_single_data csd; | |
16 | struct request *rq; | |
17 | struct bio *bio; | |
18 | unsigned int tag; | |
19 | struct nullb_queue *nq; | |
20 | }; | |
21 | ||
22 | struct nullb_queue { | |
23 | unsigned long *tag_map; | |
24 | wait_queue_head_t wait; | |
25 | unsigned int queue_depth; | |
26 | ||
27 | struct nullb_cmd *cmds; | |
28 | }; | |
29 | ||
30 | struct nullb { | |
31 | struct list_head list; | |
32 | unsigned int index; | |
33 | struct request_queue *q; | |
34 | struct gendisk *disk; | |
24d2f903 | 35 | struct blk_mq_tag_set tag_set; |
f2298c04 JA |
36 | struct hrtimer timer; |
37 | unsigned int queue_depth; | |
38 | spinlock_t lock; | |
39 | ||
40 | struct nullb_queue *queues; | |
41 | unsigned int nr_queues; | |
42 | }; | |
43 | ||
44 | static LIST_HEAD(nullb_list); | |
45 | static struct mutex lock; | |
46 | static int null_major; | |
47 | static int nullb_indexes; | |
48 | ||
49 | struct completion_queue { | |
50 | struct llist_head list; | |
51 | struct hrtimer timer; | |
52 | }; | |
53 | ||
54 | /* | |
55 | * These are per-cpu for now, they will need to be configured by the | |
56 | * complete_queues parameter and appropriately mapped. | |
57 | */ | |
58 | static DEFINE_PER_CPU(struct completion_queue, completion_queues); | |
59 | ||
60 | enum { | |
61 | NULL_IRQ_NONE = 0, | |
62 | NULL_IRQ_SOFTIRQ = 1, | |
63 | NULL_IRQ_TIMER = 2, | |
ce2c350b | 64 | }; |
f2298c04 | 65 | |
ce2c350b | 66 | enum { |
f2298c04 JA |
67 | NULL_Q_BIO = 0, |
68 | NULL_Q_RQ = 1, | |
69 | NULL_Q_MQ = 2, | |
70 | }; | |
71 | ||
2d263a78 | 72 | static int submit_queues; |
f2298c04 JA |
73 | module_param(submit_queues, int, S_IRUGO); |
74 | MODULE_PARM_DESC(submit_queues, "Number of submission queues"); | |
75 | ||
76 | static int home_node = NUMA_NO_NODE; | |
77 | module_param(home_node, int, S_IRUGO); | |
78 | MODULE_PARM_DESC(home_node, "Home node for the device"); | |
79 | ||
80 | static int queue_mode = NULL_Q_MQ; | |
709c8667 MB |
81 | |
82 | static int null_param_store_val(const char *str, int *val, int min, int max) | |
83 | { | |
84 | int ret, new_val; | |
85 | ||
86 | ret = kstrtoint(str, 10, &new_val); | |
87 | if (ret) | |
88 | return -EINVAL; | |
89 | ||
90 | if (new_val < min || new_val > max) | |
91 | return -EINVAL; | |
92 | ||
93 | *val = new_val; | |
94 | return 0; | |
95 | } | |
96 | ||
97 | static int null_set_queue_mode(const char *str, const struct kernel_param *kp) | |
98 | { | |
99 | return null_param_store_val(str, &queue_mode, NULL_Q_BIO, NULL_Q_MQ); | |
100 | } | |
101 | ||
102 | static struct kernel_param_ops null_queue_mode_param_ops = { | |
103 | .set = null_set_queue_mode, | |
104 | .get = param_get_int, | |
105 | }; | |
106 | ||
107 | device_param_cb(queue_mode, &null_queue_mode_param_ops, &queue_mode, S_IRUGO); | |
54ae81cd | 108 | MODULE_PARM_DESC(queue_mode, "Block interface to use (0=bio,1=rq,2=multiqueue)"); |
f2298c04 JA |
109 | |
110 | static int gb = 250; | |
111 | module_param(gb, int, S_IRUGO); | |
112 | MODULE_PARM_DESC(gb, "Size in GB"); | |
113 | ||
114 | static int bs = 512; | |
115 | module_param(bs, int, S_IRUGO); | |
116 | MODULE_PARM_DESC(bs, "Block size (in bytes)"); | |
117 | ||
118 | static int nr_devices = 2; | |
119 | module_param(nr_devices, int, S_IRUGO); | |
120 | MODULE_PARM_DESC(nr_devices, "Number of devices to register"); | |
121 | ||
122 | static int irqmode = NULL_IRQ_SOFTIRQ; | |
709c8667 MB |
123 | |
124 | static int null_set_irqmode(const char *str, const struct kernel_param *kp) | |
125 | { | |
126 | return null_param_store_val(str, &irqmode, NULL_IRQ_NONE, | |
127 | NULL_IRQ_TIMER); | |
128 | } | |
129 | ||
130 | static struct kernel_param_ops null_irqmode_param_ops = { | |
131 | .set = null_set_irqmode, | |
132 | .get = param_get_int, | |
133 | }; | |
134 | ||
135 | device_param_cb(irqmode, &null_irqmode_param_ops, &irqmode, S_IRUGO); | |
f2298c04 JA |
136 | MODULE_PARM_DESC(irqmode, "IRQ completion handler. 0-none, 1-softirq, 2-timer"); |
137 | ||
138 | static int completion_nsec = 10000; | |
139 | module_param(completion_nsec, int, S_IRUGO); | |
140 | MODULE_PARM_DESC(completion_nsec, "Time in ns to complete a request in hardware. Default: 10,000ns"); | |
141 | ||
142 | static int hw_queue_depth = 64; | |
143 | module_param(hw_queue_depth, int, S_IRUGO); | |
144 | MODULE_PARM_DESC(hw_queue_depth, "Queue depth for each hardware queue. Default: 64"); | |
145 | ||
20005244 | 146 | static bool use_per_node_hctx = false; |
f2298c04 | 147 | module_param(use_per_node_hctx, bool, S_IRUGO); |
20005244 | 148 | MODULE_PARM_DESC(use_per_node_hctx, "Use per-node allocation for hardware context queues. Default: false"); |
f2298c04 JA |
149 | |
150 | static void put_tag(struct nullb_queue *nq, unsigned int tag) | |
151 | { | |
152 | clear_bit_unlock(tag, nq->tag_map); | |
153 | ||
154 | if (waitqueue_active(&nq->wait)) | |
155 | wake_up(&nq->wait); | |
156 | } | |
157 | ||
158 | static unsigned int get_tag(struct nullb_queue *nq) | |
159 | { | |
160 | unsigned int tag; | |
161 | ||
162 | do { | |
163 | tag = find_first_zero_bit(nq->tag_map, nq->queue_depth); | |
164 | if (tag >= nq->queue_depth) | |
165 | return -1U; | |
166 | } while (test_and_set_bit_lock(tag, nq->tag_map)); | |
167 | ||
168 | return tag; | |
169 | } | |
170 | ||
171 | static void free_cmd(struct nullb_cmd *cmd) | |
172 | { | |
173 | put_tag(cmd->nq, cmd->tag); | |
174 | } | |
175 | ||
176 | static struct nullb_cmd *__alloc_cmd(struct nullb_queue *nq) | |
177 | { | |
178 | struct nullb_cmd *cmd; | |
179 | unsigned int tag; | |
180 | ||
181 | tag = get_tag(nq); | |
182 | if (tag != -1U) { | |
183 | cmd = &nq->cmds[tag]; | |
184 | cmd->tag = tag; | |
185 | cmd->nq = nq; | |
186 | return cmd; | |
187 | } | |
188 | ||
189 | return NULL; | |
190 | } | |
191 | ||
192 | static struct nullb_cmd *alloc_cmd(struct nullb_queue *nq, int can_wait) | |
193 | { | |
194 | struct nullb_cmd *cmd; | |
195 | DEFINE_WAIT(wait); | |
196 | ||
197 | cmd = __alloc_cmd(nq); | |
198 | if (cmd || !can_wait) | |
199 | return cmd; | |
200 | ||
201 | do { | |
202 | prepare_to_wait(&nq->wait, &wait, TASK_UNINTERRUPTIBLE); | |
203 | cmd = __alloc_cmd(nq); | |
204 | if (cmd) | |
205 | break; | |
206 | ||
207 | io_schedule(); | |
208 | } while (1); | |
209 | ||
210 | finish_wait(&nq->wait, &wait); | |
211 | return cmd; | |
212 | } | |
213 | ||
214 | static void end_cmd(struct nullb_cmd *cmd) | |
215 | { | |
ce2c350b CH |
216 | switch (queue_mode) { |
217 | case NULL_Q_MQ: | |
c8a446ad | 218 | blk_mq_end_request(cmd->rq, 0); |
ce2c350b CH |
219 | return; |
220 | case NULL_Q_RQ: | |
221 | INIT_LIST_HEAD(&cmd->rq->queuelist); | |
222 | blk_end_request_all(cmd->rq, 0); | |
223 | break; | |
224 | case NULL_Q_BIO: | |
f2298c04 | 225 | bio_endio(cmd->bio, 0); |
ce2c350b CH |
226 | break; |
227 | } | |
f2298c04 | 228 | |
ce2c350b | 229 | free_cmd(cmd); |
f2298c04 JA |
230 | } |
231 | ||
232 | static enum hrtimer_restart null_cmd_timer_expired(struct hrtimer *timer) | |
233 | { | |
234 | struct completion_queue *cq; | |
235 | struct llist_node *entry; | |
236 | struct nullb_cmd *cmd; | |
237 | ||
238 | cq = &per_cpu(completion_queues, smp_processor_id()); | |
239 | ||
240 | while ((entry = llist_del_all(&cq->list)) != NULL) { | |
d7790b92 | 241 | entry = llist_reverse_order(entry); |
f2298c04 JA |
242 | do { |
243 | cmd = container_of(entry, struct nullb_cmd, ll_list); | |
f2298c04 | 244 | entry = entry->next; |
fc27691f | 245 | end_cmd(cmd); |
f2298c04 JA |
246 | } while (entry); |
247 | } | |
248 | ||
249 | return HRTIMER_NORESTART; | |
250 | } | |
251 | ||
252 | static void null_cmd_end_timer(struct nullb_cmd *cmd) | |
253 | { | |
254 | struct completion_queue *cq = &per_cpu(completion_queues, get_cpu()); | |
255 | ||
256 | cmd->ll_list.next = NULL; | |
257 | if (llist_add(&cmd->ll_list, &cq->list)) { | |
258 | ktime_t kt = ktime_set(0, completion_nsec); | |
259 | ||
260 | hrtimer_start(&cq->timer, kt, HRTIMER_MODE_REL); | |
261 | } | |
262 | ||
263 | put_cpu(); | |
264 | } | |
265 | ||
266 | static void null_softirq_done_fn(struct request *rq) | |
267 | { | |
d891fa70 JA |
268 | if (queue_mode == NULL_Q_MQ) |
269 | end_cmd(blk_mq_rq_to_pdu(rq)); | |
270 | else | |
271 | end_cmd(rq->special); | |
f2298c04 JA |
272 | } |
273 | ||
f2298c04 JA |
274 | static inline void null_handle_cmd(struct nullb_cmd *cmd) |
275 | { | |
276 | /* Complete IO by inline, softirq or timer */ | |
277 | switch (irqmode) { | |
f2298c04 | 278 | case NULL_IRQ_SOFTIRQ: |
ce2c350b CH |
279 | switch (queue_mode) { |
280 | case NULL_Q_MQ: | |
281 | blk_mq_complete_request(cmd->rq); | |
282 | break; | |
283 | case NULL_Q_RQ: | |
284 | blk_complete_request(cmd->rq); | |
285 | break; | |
286 | case NULL_Q_BIO: | |
287 | /* | |
288 | * XXX: no proper submitting cpu information available. | |
289 | */ | |
290 | end_cmd(cmd); | |
291 | break; | |
292 | } | |
293 | break; | |
294 | case NULL_IRQ_NONE: | |
f2298c04 | 295 | end_cmd(cmd); |
f2298c04 JA |
296 | break; |
297 | case NULL_IRQ_TIMER: | |
298 | null_cmd_end_timer(cmd); | |
299 | break; | |
300 | } | |
301 | } | |
302 | ||
303 | static struct nullb_queue *nullb_to_queue(struct nullb *nullb) | |
304 | { | |
305 | int index = 0; | |
306 | ||
307 | if (nullb->nr_queues != 1) | |
308 | index = raw_smp_processor_id() / ((nr_cpu_ids + nullb->nr_queues - 1) / nullb->nr_queues); | |
309 | ||
310 | return &nullb->queues[index]; | |
311 | } | |
312 | ||
313 | static void null_queue_bio(struct request_queue *q, struct bio *bio) | |
314 | { | |
315 | struct nullb *nullb = q->queuedata; | |
316 | struct nullb_queue *nq = nullb_to_queue(nullb); | |
317 | struct nullb_cmd *cmd; | |
318 | ||
319 | cmd = alloc_cmd(nq, 1); | |
320 | cmd->bio = bio; | |
321 | ||
322 | null_handle_cmd(cmd); | |
323 | } | |
324 | ||
325 | static int null_rq_prep_fn(struct request_queue *q, struct request *req) | |
326 | { | |
327 | struct nullb *nullb = q->queuedata; | |
328 | struct nullb_queue *nq = nullb_to_queue(nullb); | |
329 | struct nullb_cmd *cmd; | |
330 | ||
331 | cmd = alloc_cmd(nq, 0); | |
332 | if (cmd) { | |
333 | cmd->rq = req; | |
334 | req->special = cmd; | |
335 | return BLKPREP_OK; | |
336 | } | |
337 | ||
338 | return BLKPREP_DEFER; | |
339 | } | |
340 | ||
341 | static void null_request_fn(struct request_queue *q) | |
342 | { | |
343 | struct request *rq; | |
344 | ||
345 | while ((rq = blk_fetch_request(q)) != NULL) { | |
346 | struct nullb_cmd *cmd = rq->special; | |
347 | ||
348 | spin_unlock_irq(q->queue_lock); | |
349 | null_handle_cmd(cmd); | |
350 | spin_lock_irq(q->queue_lock); | |
351 | } | |
352 | } | |
353 | ||
74c45052 JA |
354 | static int null_queue_rq(struct blk_mq_hw_ctx *hctx, |
355 | const struct blk_mq_queue_data *bd) | |
f2298c04 | 356 | { |
74c45052 | 357 | struct nullb_cmd *cmd = blk_mq_rq_to_pdu(bd->rq); |
f2298c04 | 358 | |
74c45052 | 359 | cmd->rq = bd->rq; |
f2298c04 JA |
360 | cmd->nq = hctx->driver_data; |
361 | ||
74c45052 | 362 | blk_mq_start_request(bd->rq); |
e2490073 | 363 | |
f2298c04 JA |
364 | null_handle_cmd(cmd); |
365 | return BLK_MQ_RQ_QUEUE_OK; | |
366 | } | |
367 | ||
2d263a78 MB |
368 | static void null_init_queue(struct nullb *nullb, struct nullb_queue *nq) |
369 | { | |
370 | BUG_ON(!nullb); | |
371 | BUG_ON(!nq); | |
372 | ||
373 | init_waitqueue_head(&nq->wait); | |
374 | nq->queue_depth = nullb->queue_depth; | |
375 | } | |
376 | ||
f2298c04 JA |
377 | static int null_init_hctx(struct blk_mq_hw_ctx *hctx, void *data, |
378 | unsigned int index) | |
379 | { | |
380 | struct nullb *nullb = data; | |
381 | struct nullb_queue *nq = &nullb->queues[index]; | |
382 | ||
f2298c04 | 383 | hctx->driver_data = nq; |
2d263a78 MB |
384 | null_init_queue(nullb, nq); |
385 | nullb->nr_queues++; | |
f2298c04 JA |
386 | |
387 | return 0; | |
388 | } | |
389 | ||
390 | static struct blk_mq_ops null_mq_ops = { | |
391 | .queue_rq = null_queue_rq, | |
392 | .map_queue = blk_mq_map_queue, | |
393 | .init_hctx = null_init_hctx, | |
ce2c350b | 394 | .complete = null_softirq_done_fn, |
f2298c04 JA |
395 | }; |
396 | ||
397 | static void null_del_dev(struct nullb *nullb) | |
398 | { | |
399 | list_del_init(&nullb->list); | |
400 | ||
401 | del_gendisk(nullb->disk); | |
518d00b7 | 402 | blk_cleanup_queue(nullb->q); |
24d2f903 CH |
403 | if (queue_mode == NULL_Q_MQ) |
404 | blk_mq_free_tag_set(&nullb->tag_set); | |
f2298c04 JA |
405 | put_disk(nullb->disk); |
406 | kfree(nullb); | |
407 | } | |
408 | ||
409 | static int null_open(struct block_device *bdev, fmode_t mode) | |
410 | { | |
411 | return 0; | |
412 | } | |
413 | ||
414 | static void null_release(struct gendisk *disk, fmode_t mode) | |
415 | { | |
416 | } | |
417 | ||
418 | static const struct block_device_operations null_fops = { | |
419 | .owner = THIS_MODULE, | |
420 | .open = null_open, | |
421 | .release = null_release, | |
422 | }; | |
423 | ||
424 | static int setup_commands(struct nullb_queue *nq) | |
425 | { | |
426 | struct nullb_cmd *cmd; | |
427 | int i, tag_size; | |
428 | ||
429 | nq->cmds = kzalloc(nq->queue_depth * sizeof(*cmd), GFP_KERNEL); | |
430 | if (!nq->cmds) | |
2d263a78 | 431 | return -ENOMEM; |
f2298c04 JA |
432 | |
433 | tag_size = ALIGN(nq->queue_depth, BITS_PER_LONG) / BITS_PER_LONG; | |
434 | nq->tag_map = kzalloc(tag_size * sizeof(unsigned long), GFP_KERNEL); | |
435 | if (!nq->tag_map) { | |
436 | kfree(nq->cmds); | |
2d263a78 | 437 | return -ENOMEM; |
f2298c04 JA |
438 | } |
439 | ||
440 | for (i = 0; i < nq->queue_depth; i++) { | |
441 | cmd = &nq->cmds[i]; | |
442 | INIT_LIST_HEAD(&cmd->list); | |
443 | cmd->ll_list.next = NULL; | |
444 | cmd->tag = -1U; | |
445 | } | |
446 | ||
447 | return 0; | |
448 | } | |
449 | ||
450 | static void cleanup_queue(struct nullb_queue *nq) | |
451 | { | |
452 | kfree(nq->tag_map); | |
453 | kfree(nq->cmds); | |
454 | } | |
455 | ||
456 | static void cleanup_queues(struct nullb *nullb) | |
457 | { | |
458 | int i; | |
459 | ||
460 | for (i = 0; i < nullb->nr_queues; i++) | |
461 | cleanup_queue(&nullb->queues[i]); | |
462 | ||
463 | kfree(nullb->queues); | |
464 | } | |
465 | ||
466 | static int setup_queues(struct nullb *nullb) | |
467 | { | |
2d263a78 MB |
468 | nullb->queues = kzalloc(submit_queues * sizeof(struct nullb_queue), |
469 | GFP_KERNEL); | |
f2298c04 | 470 | if (!nullb->queues) |
2d263a78 | 471 | return -ENOMEM; |
f2298c04 JA |
472 | |
473 | nullb->nr_queues = 0; | |
474 | nullb->queue_depth = hw_queue_depth; | |
475 | ||
2d263a78 MB |
476 | return 0; |
477 | } | |
478 | ||
479 | static int init_driver_queues(struct nullb *nullb) | |
480 | { | |
481 | struct nullb_queue *nq; | |
482 | int i, ret = 0; | |
f2298c04 JA |
483 | |
484 | for (i = 0; i < submit_queues; i++) { | |
485 | nq = &nullb->queues[i]; | |
2d263a78 MB |
486 | |
487 | null_init_queue(nullb, nq); | |
488 | ||
489 | ret = setup_commands(nq); | |
490 | if (ret) | |
31f9690e | 491 | return ret; |
f2298c04 JA |
492 | nullb->nr_queues++; |
493 | } | |
2d263a78 | 494 | return 0; |
f2298c04 JA |
495 | } |
496 | ||
497 | static int null_add_dev(void) | |
498 | { | |
499 | struct gendisk *disk; | |
500 | struct nullb *nullb; | |
501 | sector_t size; | |
dc501dc0 | 502 | int rv; |
f2298c04 JA |
503 | |
504 | nullb = kzalloc_node(sizeof(*nullb), GFP_KERNEL, home_node); | |
dc501dc0 RE |
505 | if (!nullb) { |
506 | rv = -ENOMEM; | |
24d2f903 | 507 | goto out; |
dc501dc0 | 508 | } |
f2298c04 JA |
509 | |
510 | spin_lock_init(&nullb->lock); | |
511 | ||
57053d8c MB |
512 | if (queue_mode == NULL_Q_MQ && use_per_node_hctx) |
513 | submit_queues = nr_online_nodes; | |
514 | ||
dc501dc0 RE |
515 | rv = setup_queues(nullb); |
516 | if (rv) | |
24d2f903 | 517 | goto out_free_nullb; |
f2298c04 JA |
518 | |
519 | if (queue_mode == NULL_Q_MQ) { | |
cdef54dd | 520 | nullb->tag_set.ops = &null_mq_ops; |
24d2f903 CH |
521 | nullb->tag_set.nr_hw_queues = submit_queues; |
522 | nullb->tag_set.queue_depth = hw_queue_depth; | |
523 | nullb->tag_set.numa_node = home_node; | |
524 | nullb->tag_set.cmd_size = sizeof(struct nullb_cmd); | |
525 | nullb->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; | |
526 | nullb->tag_set.driver_data = nullb; | |
527 | ||
dc501dc0 RE |
528 | rv = blk_mq_alloc_tag_set(&nullb->tag_set); |
529 | if (rv) | |
24d2f903 CH |
530 | goto out_cleanup_queues; |
531 | ||
532 | nullb->q = blk_mq_init_queue(&nullb->tag_set); | |
dc501dc0 RE |
533 | if (!nullb->q) { |
534 | rv = -ENOMEM; | |
24d2f903 | 535 | goto out_cleanup_tags; |
dc501dc0 | 536 | } |
f2298c04 JA |
537 | } else if (queue_mode == NULL_Q_BIO) { |
538 | nullb->q = blk_alloc_queue_node(GFP_KERNEL, home_node); | |
dc501dc0 RE |
539 | if (!nullb->q) { |
540 | rv = -ENOMEM; | |
24d2f903 | 541 | goto out_cleanup_queues; |
dc501dc0 | 542 | } |
f2298c04 | 543 | blk_queue_make_request(nullb->q, null_queue_bio); |
31f9690e JK |
544 | rv = init_driver_queues(nullb); |
545 | if (rv) | |
546 | goto out_cleanup_blk_queue; | |
f2298c04 JA |
547 | } else { |
548 | nullb->q = blk_init_queue_node(null_request_fn, &nullb->lock, home_node); | |
dc501dc0 RE |
549 | if (!nullb->q) { |
550 | rv = -ENOMEM; | |
24d2f903 | 551 | goto out_cleanup_queues; |
dc501dc0 | 552 | } |
f2298c04 | 553 | blk_queue_prep_rq(nullb->q, null_rq_prep_fn); |
24d2f903 | 554 | blk_queue_softirq_done(nullb->q, null_softirq_done_fn); |
31f9690e JK |
555 | rv = init_driver_queues(nullb); |
556 | if (rv) | |
557 | goto out_cleanup_blk_queue; | |
f2298c04 JA |
558 | } |
559 | ||
f2298c04 JA |
560 | nullb->q->queuedata = nullb; |
561 | queue_flag_set_unlocked(QUEUE_FLAG_NONROT, nullb->q); | |
b277da0a | 562 | queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, nullb->q); |
f2298c04 JA |
563 | |
564 | disk = nullb->disk = alloc_disk_node(1, home_node); | |
dc501dc0 RE |
565 | if (!disk) { |
566 | rv = -ENOMEM; | |
24d2f903 | 567 | goto out_cleanup_blk_queue; |
dc501dc0 | 568 | } |
f2298c04 JA |
569 | |
570 | mutex_lock(&lock); | |
571 | list_add_tail(&nullb->list, &nullb_list); | |
572 | nullb->index = nullb_indexes++; | |
573 | mutex_unlock(&lock); | |
574 | ||
575 | blk_queue_logical_block_size(nullb->q, bs); | |
576 | blk_queue_physical_block_size(nullb->q, bs); | |
577 | ||
578 | size = gb * 1024 * 1024 * 1024ULL; | |
579 | sector_div(size, bs); | |
580 | set_capacity(disk, size); | |
581 | ||
582 | disk->flags |= GENHD_FL_EXT_DEVT; | |
583 | disk->major = null_major; | |
584 | disk->first_minor = nullb->index; | |
585 | disk->fops = &null_fops; | |
586 | disk->private_data = nullb; | |
587 | disk->queue = nullb->q; | |
588 | sprintf(disk->disk_name, "nullb%d", nullb->index); | |
589 | add_disk(disk); | |
590 | return 0; | |
24d2f903 CH |
591 | |
592 | out_cleanup_blk_queue: | |
593 | blk_cleanup_queue(nullb->q); | |
594 | out_cleanup_tags: | |
595 | if (queue_mode == NULL_Q_MQ) | |
596 | blk_mq_free_tag_set(&nullb->tag_set); | |
597 | out_cleanup_queues: | |
598 | cleanup_queues(nullb); | |
599 | out_free_nullb: | |
600 | kfree(nullb); | |
601 | out: | |
dc501dc0 | 602 | return rv; |
f2298c04 JA |
603 | } |
604 | ||
605 | static int __init null_init(void) | |
606 | { | |
607 | unsigned int i; | |
608 | ||
9967d8ac R |
609 | if (bs > PAGE_SIZE) { |
610 | pr_warn("null_blk: invalid block size\n"); | |
611 | pr_warn("null_blk: defaults block size to %lu\n", PAGE_SIZE); | |
612 | bs = PAGE_SIZE; | |
613 | } | |
f2298c04 | 614 | |
d15ee6b1 | 615 | if (queue_mode == NULL_Q_MQ && use_per_node_hctx) { |
fc1bc354 | 616 | if (submit_queues < nr_online_nodes) { |
d15ee6b1 MB |
617 | pr_warn("null_blk: submit_queues param is set to %u.", |
618 | nr_online_nodes); | |
fc1bc354 MB |
619 | submit_queues = nr_online_nodes; |
620 | } | |
d15ee6b1 | 621 | } else if (submit_queues > nr_cpu_ids) |
f2298c04 JA |
622 | submit_queues = nr_cpu_ids; |
623 | else if (!submit_queues) | |
624 | submit_queues = 1; | |
625 | ||
626 | mutex_init(&lock); | |
627 | ||
628 | /* Initialize a separate list for each CPU for issuing softirqs */ | |
629 | for_each_possible_cpu(i) { | |
630 | struct completion_queue *cq = &per_cpu(completion_queues, i); | |
631 | ||
632 | init_llist_head(&cq->list); | |
633 | ||
634 | if (irqmode != NULL_IRQ_TIMER) | |
635 | continue; | |
636 | ||
637 | hrtimer_init(&cq->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); | |
638 | cq->timer.function = null_cmd_timer_expired; | |
639 | } | |
640 | ||
641 | null_major = register_blkdev(0, "nullb"); | |
642 | if (null_major < 0) | |
643 | return null_major; | |
644 | ||
645 | for (i = 0; i < nr_devices; i++) { | |
646 | if (null_add_dev()) { | |
647 | unregister_blkdev(null_major, "nullb"); | |
648 | return -EINVAL; | |
649 | } | |
650 | } | |
651 | ||
652 | pr_info("null: module loaded\n"); | |
653 | return 0; | |
654 | } | |
655 | ||
656 | static void __exit null_exit(void) | |
657 | { | |
658 | struct nullb *nullb; | |
659 | ||
660 | unregister_blkdev(null_major, "nullb"); | |
661 | ||
662 | mutex_lock(&lock); | |
663 | while (!list_empty(&nullb_list)) { | |
664 | nullb = list_entry(nullb_list.next, struct nullb, list); | |
665 | null_del_dev(nullb); | |
666 | } | |
667 | mutex_unlock(&lock); | |
668 | } | |
669 | ||
670 | module_init(null_init); | |
671 | module_exit(null_exit); | |
672 | ||
673 | MODULE_AUTHOR("Jens Axboe <jaxboe@fusionio.com>"); | |
674 | MODULE_LICENSE("GPL"); |