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 | ||
9c27847d | 102 | static const struct kernel_param_ops null_queue_mode_param_ops = { |
709c8667 MB |
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 | ||
9c27847d | 130 | static const struct kernel_param_ops null_irqmode_param_ops = { |
709c8667 MB |
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: | |
4246a0b6 | 225 | bio_endio(cmd->bio); |
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 | 242 | do { |
21974061 MK |
243 | struct request_queue *q = NULL; |
244 | ||
f2298c04 | 245 | cmd = container_of(entry, struct nullb_cmd, ll_list); |
f2298c04 | 246 | entry = entry->next; |
21974061 MK |
247 | if (cmd->rq) |
248 | q = cmd->rq->q; | |
fc27691f | 249 | end_cmd(cmd); |
8b70f45e | 250 | |
21974061 MK |
251 | if (q && !q->mq_ops && blk_queue_stopped(q)) { |
252 | spin_lock(q->queue_lock); | |
253 | if (blk_queue_stopped(q)) | |
254 | blk_start_queue(q); | |
255 | spin_unlock(q->queue_lock); | |
8b70f45e | 256 | } |
f2298c04 JA |
257 | } while (entry); |
258 | } | |
259 | ||
260 | return HRTIMER_NORESTART; | |
261 | } | |
262 | ||
263 | static void null_cmd_end_timer(struct nullb_cmd *cmd) | |
264 | { | |
265 | struct completion_queue *cq = &per_cpu(completion_queues, get_cpu()); | |
266 | ||
267 | cmd->ll_list.next = NULL; | |
268 | if (llist_add(&cmd->ll_list, &cq->list)) { | |
269 | ktime_t kt = ktime_set(0, completion_nsec); | |
270 | ||
419c21a3 | 271 | hrtimer_start(&cq->timer, kt, HRTIMER_MODE_REL_PINNED); |
f2298c04 JA |
272 | } |
273 | ||
274 | put_cpu(); | |
275 | } | |
276 | ||
277 | static void null_softirq_done_fn(struct request *rq) | |
278 | { | |
d891fa70 JA |
279 | if (queue_mode == NULL_Q_MQ) |
280 | end_cmd(blk_mq_rq_to_pdu(rq)); | |
281 | else | |
282 | end_cmd(rq->special); | |
f2298c04 JA |
283 | } |
284 | ||
f2298c04 JA |
285 | static inline void null_handle_cmd(struct nullb_cmd *cmd) |
286 | { | |
287 | /* Complete IO by inline, softirq or timer */ | |
288 | switch (irqmode) { | |
f2298c04 | 289 | case NULL_IRQ_SOFTIRQ: |
ce2c350b CH |
290 | switch (queue_mode) { |
291 | case NULL_Q_MQ: | |
f4829a9b | 292 | blk_mq_complete_request(cmd->rq, cmd->rq->errors); |
ce2c350b CH |
293 | break; |
294 | case NULL_Q_RQ: | |
295 | blk_complete_request(cmd->rq); | |
296 | break; | |
297 | case NULL_Q_BIO: | |
298 | /* | |
299 | * XXX: no proper submitting cpu information available. | |
300 | */ | |
301 | end_cmd(cmd); | |
302 | break; | |
303 | } | |
304 | break; | |
305 | case NULL_IRQ_NONE: | |
f2298c04 | 306 | end_cmd(cmd); |
f2298c04 JA |
307 | break; |
308 | case NULL_IRQ_TIMER: | |
309 | null_cmd_end_timer(cmd); | |
310 | break; | |
311 | } | |
312 | } | |
313 | ||
314 | static struct nullb_queue *nullb_to_queue(struct nullb *nullb) | |
315 | { | |
316 | int index = 0; | |
317 | ||
318 | if (nullb->nr_queues != 1) | |
319 | index = raw_smp_processor_id() / ((nr_cpu_ids + nullb->nr_queues - 1) / nullb->nr_queues); | |
320 | ||
321 | return &nullb->queues[index]; | |
322 | } | |
323 | ||
dece1635 | 324 | static blk_qc_t null_queue_bio(struct request_queue *q, struct bio *bio) |
f2298c04 JA |
325 | { |
326 | struct nullb *nullb = q->queuedata; | |
327 | struct nullb_queue *nq = nullb_to_queue(nullb); | |
328 | struct nullb_cmd *cmd; | |
329 | ||
330 | cmd = alloc_cmd(nq, 1); | |
331 | cmd->bio = bio; | |
332 | ||
333 | null_handle_cmd(cmd); | |
dece1635 | 334 | return BLK_QC_T_NONE; |
f2298c04 JA |
335 | } |
336 | ||
337 | static int null_rq_prep_fn(struct request_queue *q, struct request *req) | |
338 | { | |
339 | struct nullb *nullb = q->queuedata; | |
340 | struct nullb_queue *nq = nullb_to_queue(nullb); | |
341 | struct nullb_cmd *cmd; | |
342 | ||
343 | cmd = alloc_cmd(nq, 0); | |
344 | if (cmd) { | |
345 | cmd->rq = req; | |
346 | req->special = cmd; | |
347 | return BLKPREP_OK; | |
348 | } | |
8b70f45e | 349 | blk_stop_queue(q); |
f2298c04 JA |
350 | |
351 | return BLKPREP_DEFER; | |
352 | } | |
353 | ||
354 | static void null_request_fn(struct request_queue *q) | |
355 | { | |
356 | struct request *rq; | |
357 | ||
358 | while ((rq = blk_fetch_request(q)) != NULL) { | |
359 | struct nullb_cmd *cmd = rq->special; | |
360 | ||
361 | spin_unlock_irq(q->queue_lock); | |
362 | null_handle_cmd(cmd); | |
363 | spin_lock_irq(q->queue_lock); | |
364 | } | |
365 | } | |
366 | ||
74c45052 JA |
367 | static int null_queue_rq(struct blk_mq_hw_ctx *hctx, |
368 | const struct blk_mq_queue_data *bd) | |
f2298c04 | 369 | { |
74c45052 | 370 | struct nullb_cmd *cmd = blk_mq_rq_to_pdu(bd->rq); |
f2298c04 | 371 | |
74c45052 | 372 | cmd->rq = bd->rq; |
f2298c04 JA |
373 | cmd->nq = hctx->driver_data; |
374 | ||
74c45052 | 375 | blk_mq_start_request(bd->rq); |
e2490073 | 376 | |
f2298c04 JA |
377 | null_handle_cmd(cmd); |
378 | return BLK_MQ_RQ_QUEUE_OK; | |
379 | } | |
380 | ||
2d263a78 MB |
381 | static void null_init_queue(struct nullb *nullb, struct nullb_queue *nq) |
382 | { | |
383 | BUG_ON(!nullb); | |
384 | BUG_ON(!nq); | |
385 | ||
386 | init_waitqueue_head(&nq->wait); | |
387 | nq->queue_depth = nullb->queue_depth; | |
388 | } | |
389 | ||
f2298c04 JA |
390 | static int null_init_hctx(struct blk_mq_hw_ctx *hctx, void *data, |
391 | unsigned int index) | |
392 | { | |
393 | struct nullb *nullb = data; | |
394 | struct nullb_queue *nq = &nullb->queues[index]; | |
395 | ||
f2298c04 | 396 | hctx->driver_data = nq; |
2d263a78 MB |
397 | null_init_queue(nullb, nq); |
398 | nullb->nr_queues++; | |
f2298c04 JA |
399 | |
400 | return 0; | |
401 | } | |
402 | ||
403 | static struct blk_mq_ops null_mq_ops = { | |
404 | .queue_rq = null_queue_rq, | |
405 | .map_queue = blk_mq_map_queue, | |
406 | .init_hctx = null_init_hctx, | |
ce2c350b | 407 | .complete = null_softirq_done_fn, |
f2298c04 JA |
408 | }; |
409 | ||
de65d2d2 MB |
410 | static void cleanup_queue(struct nullb_queue *nq) |
411 | { | |
412 | kfree(nq->tag_map); | |
413 | kfree(nq->cmds); | |
414 | } | |
415 | ||
416 | static void cleanup_queues(struct nullb *nullb) | |
417 | { | |
418 | int i; | |
419 | ||
420 | for (i = 0; i < nullb->nr_queues; i++) | |
421 | cleanup_queue(&nullb->queues[i]); | |
422 | ||
423 | kfree(nullb->queues); | |
424 | } | |
425 | ||
f2298c04 JA |
426 | static void null_del_dev(struct nullb *nullb) |
427 | { | |
428 | list_del_init(&nullb->list); | |
429 | ||
430 | del_gendisk(nullb->disk); | |
518d00b7 | 431 | blk_cleanup_queue(nullb->q); |
24d2f903 CH |
432 | if (queue_mode == NULL_Q_MQ) |
433 | blk_mq_free_tag_set(&nullb->tag_set); | |
f2298c04 | 434 | put_disk(nullb->disk); |
de65d2d2 | 435 | cleanup_queues(nullb); |
f2298c04 JA |
436 | kfree(nullb); |
437 | } | |
438 | ||
439 | static int null_open(struct block_device *bdev, fmode_t mode) | |
440 | { | |
441 | return 0; | |
442 | } | |
443 | ||
444 | static void null_release(struct gendisk *disk, fmode_t mode) | |
445 | { | |
446 | } | |
447 | ||
448 | static const struct block_device_operations null_fops = { | |
449 | .owner = THIS_MODULE, | |
450 | .open = null_open, | |
451 | .release = null_release, | |
452 | }; | |
453 | ||
454 | static int setup_commands(struct nullb_queue *nq) | |
455 | { | |
456 | struct nullb_cmd *cmd; | |
457 | int i, tag_size; | |
458 | ||
459 | nq->cmds = kzalloc(nq->queue_depth * sizeof(*cmd), GFP_KERNEL); | |
460 | if (!nq->cmds) | |
2d263a78 | 461 | return -ENOMEM; |
f2298c04 JA |
462 | |
463 | tag_size = ALIGN(nq->queue_depth, BITS_PER_LONG) / BITS_PER_LONG; | |
464 | nq->tag_map = kzalloc(tag_size * sizeof(unsigned long), GFP_KERNEL); | |
465 | if (!nq->tag_map) { | |
466 | kfree(nq->cmds); | |
2d263a78 | 467 | return -ENOMEM; |
f2298c04 JA |
468 | } |
469 | ||
470 | for (i = 0; i < nq->queue_depth; i++) { | |
471 | cmd = &nq->cmds[i]; | |
472 | INIT_LIST_HEAD(&cmd->list); | |
473 | cmd->ll_list.next = NULL; | |
474 | cmd->tag = -1U; | |
475 | } | |
476 | ||
477 | return 0; | |
478 | } | |
479 | ||
f2298c04 JA |
480 | static int setup_queues(struct nullb *nullb) |
481 | { | |
2d263a78 MB |
482 | nullb->queues = kzalloc(submit_queues * sizeof(struct nullb_queue), |
483 | GFP_KERNEL); | |
f2298c04 | 484 | if (!nullb->queues) |
2d263a78 | 485 | return -ENOMEM; |
f2298c04 JA |
486 | |
487 | nullb->nr_queues = 0; | |
488 | nullb->queue_depth = hw_queue_depth; | |
489 | ||
2d263a78 MB |
490 | return 0; |
491 | } | |
492 | ||
493 | static int init_driver_queues(struct nullb *nullb) | |
494 | { | |
495 | struct nullb_queue *nq; | |
496 | int i, ret = 0; | |
f2298c04 JA |
497 | |
498 | for (i = 0; i < submit_queues; i++) { | |
499 | nq = &nullb->queues[i]; | |
2d263a78 MB |
500 | |
501 | null_init_queue(nullb, nq); | |
502 | ||
503 | ret = setup_commands(nq); | |
504 | if (ret) | |
31f9690e | 505 | return ret; |
f2298c04 JA |
506 | nullb->nr_queues++; |
507 | } | |
2d263a78 | 508 | return 0; |
f2298c04 JA |
509 | } |
510 | ||
511 | static int null_add_dev(void) | |
512 | { | |
513 | struct gendisk *disk; | |
514 | struct nullb *nullb; | |
515 | sector_t size; | |
dc501dc0 | 516 | int rv; |
f2298c04 JA |
517 | |
518 | nullb = kzalloc_node(sizeof(*nullb), GFP_KERNEL, home_node); | |
dc501dc0 RE |
519 | if (!nullb) { |
520 | rv = -ENOMEM; | |
24d2f903 | 521 | goto out; |
dc501dc0 | 522 | } |
f2298c04 JA |
523 | |
524 | spin_lock_init(&nullb->lock); | |
525 | ||
57053d8c MB |
526 | if (queue_mode == NULL_Q_MQ && use_per_node_hctx) |
527 | submit_queues = nr_online_nodes; | |
528 | ||
dc501dc0 RE |
529 | rv = setup_queues(nullb); |
530 | if (rv) | |
24d2f903 | 531 | goto out_free_nullb; |
f2298c04 JA |
532 | |
533 | if (queue_mode == NULL_Q_MQ) { | |
cdef54dd | 534 | nullb->tag_set.ops = &null_mq_ops; |
24d2f903 CH |
535 | nullb->tag_set.nr_hw_queues = submit_queues; |
536 | nullb->tag_set.queue_depth = hw_queue_depth; | |
537 | nullb->tag_set.numa_node = home_node; | |
538 | nullb->tag_set.cmd_size = sizeof(struct nullb_cmd); | |
539 | nullb->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; | |
540 | nullb->tag_set.driver_data = nullb; | |
541 | ||
dc501dc0 RE |
542 | rv = blk_mq_alloc_tag_set(&nullb->tag_set); |
543 | if (rv) | |
24d2f903 CH |
544 | goto out_cleanup_queues; |
545 | ||
546 | nullb->q = blk_mq_init_queue(&nullb->tag_set); | |
35b489d3 | 547 | if (IS_ERR(nullb->q)) { |
dc501dc0 | 548 | rv = -ENOMEM; |
24d2f903 | 549 | goto out_cleanup_tags; |
dc501dc0 | 550 | } |
f2298c04 JA |
551 | } else if (queue_mode == NULL_Q_BIO) { |
552 | nullb->q = blk_alloc_queue_node(GFP_KERNEL, home_node); | |
dc501dc0 RE |
553 | if (!nullb->q) { |
554 | rv = -ENOMEM; | |
24d2f903 | 555 | goto out_cleanup_queues; |
dc501dc0 | 556 | } |
f2298c04 | 557 | blk_queue_make_request(nullb->q, null_queue_bio); |
31f9690e JK |
558 | rv = init_driver_queues(nullb); |
559 | if (rv) | |
560 | goto out_cleanup_blk_queue; | |
f2298c04 JA |
561 | } else { |
562 | nullb->q = blk_init_queue_node(null_request_fn, &nullb->lock, home_node); | |
dc501dc0 RE |
563 | if (!nullb->q) { |
564 | rv = -ENOMEM; | |
24d2f903 | 565 | goto out_cleanup_queues; |
dc501dc0 | 566 | } |
f2298c04 | 567 | blk_queue_prep_rq(nullb->q, null_rq_prep_fn); |
24d2f903 | 568 | blk_queue_softirq_done(nullb->q, null_softirq_done_fn); |
31f9690e JK |
569 | rv = init_driver_queues(nullb); |
570 | if (rv) | |
571 | goto out_cleanup_blk_queue; | |
f2298c04 JA |
572 | } |
573 | ||
f2298c04 JA |
574 | nullb->q->queuedata = nullb; |
575 | queue_flag_set_unlocked(QUEUE_FLAG_NONROT, nullb->q); | |
b277da0a | 576 | queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, nullb->q); |
f2298c04 JA |
577 | |
578 | disk = nullb->disk = alloc_disk_node(1, home_node); | |
dc501dc0 RE |
579 | if (!disk) { |
580 | rv = -ENOMEM; | |
24d2f903 | 581 | goto out_cleanup_blk_queue; |
dc501dc0 | 582 | } |
f2298c04 JA |
583 | |
584 | mutex_lock(&lock); | |
585 | list_add_tail(&nullb->list, &nullb_list); | |
586 | nullb->index = nullb_indexes++; | |
587 | mutex_unlock(&lock); | |
588 | ||
589 | blk_queue_logical_block_size(nullb->q, bs); | |
590 | blk_queue_physical_block_size(nullb->q, bs); | |
591 | ||
592 | size = gb * 1024 * 1024 * 1024ULL; | |
5fdb7e1b | 593 | set_capacity(disk, size >> 9); |
f2298c04 | 594 | |
227290b4 | 595 | disk->flags |= GENHD_FL_EXT_DEVT | GENHD_FL_SUPPRESS_PARTITION_INFO; |
f2298c04 JA |
596 | disk->major = null_major; |
597 | disk->first_minor = nullb->index; | |
598 | disk->fops = &null_fops; | |
599 | disk->private_data = nullb; | |
600 | disk->queue = nullb->q; | |
601 | sprintf(disk->disk_name, "nullb%d", nullb->index); | |
602 | add_disk(disk); | |
603 | return 0; | |
24d2f903 CH |
604 | |
605 | out_cleanup_blk_queue: | |
606 | blk_cleanup_queue(nullb->q); | |
607 | out_cleanup_tags: | |
608 | if (queue_mode == NULL_Q_MQ) | |
609 | blk_mq_free_tag_set(&nullb->tag_set); | |
610 | out_cleanup_queues: | |
611 | cleanup_queues(nullb); | |
612 | out_free_nullb: | |
613 | kfree(nullb); | |
614 | out: | |
dc501dc0 | 615 | return rv; |
f2298c04 JA |
616 | } |
617 | ||
618 | static int __init null_init(void) | |
619 | { | |
620 | unsigned int i; | |
621 | ||
9967d8ac R |
622 | if (bs > PAGE_SIZE) { |
623 | pr_warn("null_blk: invalid block size\n"); | |
624 | pr_warn("null_blk: defaults block size to %lu\n", PAGE_SIZE); | |
625 | bs = PAGE_SIZE; | |
626 | } | |
f2298c04 | 627 | |
d15ee6b1 | 628 | if (queue_mode == NULL_Q_MQ && use_per_node_hctx) { |
fc1bc354 | 629 | if (submit_queues < nr_online_nodes) { |
d15ee6b1 MB |
630 | pr_warn("null_blk: submit_queues param is set to %u.", |
631 | nr_online_nodes); | |
fc1bc354 MB |
632 | submit_queues = nr_online_nodes; |
633 | } | |
d15ee6b1 | 634 | } else if (submit_queues > nr_cpu_ids) |
f2298c04 JA |
635 | submit_queues = nr_cpu_ids; |
636 | else if (!submit_queues) | |
637 | submit_queues = 1; | |
638 | ||
639 | mutex_init(&lock); | |
640 | ||
641 | /* Initialize a separate list for each CPU for issuing softirqs */ | |
642 | for_each_possible_cpu(i) { | |
643 | struct completion_queue *cq = &per_cpu(completion_queues, i); | |
644 | ||
645 | init_llist_head(&cq->list); | |
646 | ||
647 | if (irqmode != NULL_IRQ_TIMER) | |
648 | continue; | |
649 | ||
650 | hrtimer_init(&cq->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); | |
651 | cq->timer.function = null_cmd_timer_expired; | |
652 | } | |
653 | ||
654 | null_major = register_blkdev(0, "nullb"); | |
655 | if (null_major < 0) | |
656 | return null_major; | |
657 | ||
658 | for (i = 0; i < nr_devices; i++) { | |
659 | if (null_add_dev()) { | |
660 | unregister_blkdev(null_major, "nullb"); | |
661 | return -EINVAL; | |
662 | } | |
663 | } | |
664 | ||
665 | pr_info("null: module loaded\n"); | |
666 | return 0; | |
667 | } | |
668 | ||
669 | static void __exit null_exit(void) | |
670 | { | |
671 | struct nullb *nullb; | |
672 | ||
673 | unregister_blkdev(null_major, "nullb"); | |
674 | ||
675 | mutex_lock(&lock); | |
676 | while (!list_empty(&nullb_list)) { | |
677 | nullb = list_entry(nullb_list.next, struct nullb, list); | |
678 | null_del_dev(nullb); | |
679 | } | |
680 | mutex_unlock(&lock); | |
681 | } | |
682 | ||
683 | module_init(null_init); | |
684 | module_exit(null_exit); | |
685 | ||
686 | MODULE_AUTHOR("Jens Axboe <jaxboe@fusionio.com>"); | |
687 | MODULE_LICENSE("GPL"); |