Commit | Line | Data |
---|---|---|
4f28f523 JA |
1 | /* |
2 | * TODO | |
3 | * | |
4 | * - Proper ioctls | |
5 | * - Get rid of device list? | |
6 | */ | |
7 | #include <linux/kernel.h> | |
8 | #include <linux/module.h> | |
9 | #include <linux/init.h> | |
10 | #include <linux/poll.h> | |
11 | #include <linux/slab.h> | |
12 | #include <linux/idr.h> | |
13 | #include <linux/file.h> | |
14 | #include <linux/miscdevice.h> | |
15 | #include <linux/cdev.h> | |
16 | #include <linux/bio.h> | |
17 | #include <linux/blkdev.h> | |
18 | ||
19 | #include "kcompat.h" | |
20 | #include "binject.h" | |
21 | ||
22 | static LIST_HEAD(b_dev_list); | |
23 | static DEFINE_SPINLOCK(b_dev_lock); | |
24 | static DEFINE_IDR(b_minor_idr); | |
25 | static struct kmem_cache *b_slab; | |
26 | static struct class *b_class; | |
27 | static int b_major; | |
28 | ||
29 | #define B_MAX_DEVS 64 | |
30 | ||
31 | struct b_dev { | |
32 | struct list_head device_list; | |
33 | struct list_head done_list; | |
34 | atomic_t in_flight; | |
35 | unsigned int done_cmds; | |
36 | wait_queue_head_t wq_done; | |
37 | struct block_device *bdev; | |
38 | spinlock_t lock; | |
39 | atomic_t ref; | |
40 | struct file *file; | |
41 | struct device *dev; | |
42 | int minor; | |
43 | struct rcu_head rcu_free; | |
44 | }; | |
45 | ||
46 | struct b_cmd { | |
47 | struct list_head list; | |
48 | struct b_dev *bd; | |
49 | struct bio *bio; | |
50 | struct b_user_cmd cmd; | |
51 | u64 issue_time; | |
52 | }; | |
53 | ||
54 | static const unsigned long uc_flag_map[__B_FLAG_NR] = { | |
55 | B_REQ_SYNC, | |
56 | B_REQ_UNPLUG, | |
57 | B_REQ_NOIDLE, | |
58 | B_REQ_HARDBARRIER, | |
59 | B_REQ_META, | |
60 | B_REQ_RAHEAD, | |
61 | B_REQ_FAILFAST_DEV, | |
62 | B_REQ_FAILFAST_TRANSPORT, | |
63 | B_REQ_FAILFAST_DRIVER | |
64 | }; | |
65 | ||
66 | struct uc_map { | |
67 | int type; | |
68 | unsigned int data_transfer : 1; | |
69 | unsigned int todevice : 1; | |
70 | unsigned int map_zero : 1; | |
71 | }; | |
72 | ||
73 | static const struct uc_map uc_map[B_TYPE_NR] = { | |
74 | { | |
75 | .type = B_TYPE_READ, | |
76 | .data_transfer = 1, | |
77 | .todevice = 0, | |
78 | .map_zero = 0, | |
79 | }, | |
80 | { | |
81 | .type = B_TYPE_WRITE, | |
82 | .data_transfer = 1, | |
83 | .todevice = 1, | |
84 | .map_zero = 0, | |
85 | }, | |
86 | { | |
87 | .type = B_TYPE_DISCARD, | |
88 | .data_transfer = 0, | |
89 | .todevice = 0, | |
90 | .map_zero = 0, | |
91 | }, | |
92 | { | |
93 | .type = B_TYPE_READVOID, | |
94 | .data_transfer = 1, | |
95 | .todevice = 0, | |
96 | .map_zero = 1, | |
97 | }, | |
98 | { | |
99 | .type = B_TYPE_WRITEZERO, | |
100 | .data_transfer = 1, | |
101 | .todevice = 1, | |
102 | .map_zero = 1, | |
103 | } | |
104 | }; | |
105 | ||
106 | static void b_dev_complete_commands(struct b_dev *bd); | |
107 | ||
108 | static void b_dev_remove_lookup(struct b_dev *bd) | |
109 | { | |
110 | if (!list_empty(&bd->device_list)) { | |
111 | list_del_init(&bd->device_list); | |
112 | idr_remove(&b_minor_idr, bd->minor); | |
113 | } | |
114 | } | |
115 | ||
116 | static void bd_rcu_free(struct rcu_head *head) | |
117 | { | |
118 | kfree(container_of(head, struct b_dev, rcu_free)); | |
119 | } | |
120 | ||
121 | static void b_dev_put(struct b_dev *bd) | |
122 | { | |
123 | if (!atomic_dec_and_test(&bd->ref)) | |
124 | return; | |
125 | ||
126 | spin_lock(&b_dev_lock); | |
127 | b_dev_remove_lookup(bd); | |
128 | spin_unlock(&b_dev_lock); | |
129 | ||
130 | b_dev_complete_commands(bd); | |
131 | ||
132 | device_destroy(b_class, MKDEV(b_major, bd->minor)); | |
133 | fput(bd->file); | |
134 | module_put(THIS_MODULE); | |
135 | ||
136 | call_rcu(&bd->rcu_free, bd_rcu_free); | |
137 | } | |
138 | ||
139 | static struct b_cmd *get_free_command(struct b_dev *bd) | |
140 | { | |
141 | struct b_cmd *bc; | |
142 | ||
143 | bc = kmem_cache_alloc(b_slab, GFP_KERNEL); | |
144 | if (bc) { | |
145 | memset(bc, 0, sizeof(*bc)); | |
146 | INIT_LIST_HEAD(&bc->list); | |
147 | bc->bd = bd; | |
148 | return bc; | |
149 | } | |
150 | ||
151 | return ERR_PTR(-ENOMEM); | |
152 | } | |
153 | ||
154 | static struct b_cmd *get_completed_command(struct b_dev *bd) | |
155 | { | |
156 | struct b_cmd *bc = NULL; | |
157 | ||
158 | spin_lock_irq(&bd->lock); | |
159 | if (!list_empty(&bd->done_list)) { | |
160 | bc = list_entry(bd->done_list.next, struct b_cmd, list); | |
161 | bd->done_cmds--; | |
162 | list_del(&bc->list); | |
163 | } | |
164 | spin_unlock_irq(&bd->lock); | |
165 | return bc; | |
166 | } | |
167 | ||
168 | static struct b_cmd *get_done_command(struct b_dev *bd, int block) | |
169 | { | |
170 | struct b_cmd *bc; | |
171 | int ret; | |
172 | ||
173 | do { | |
174 | bc = get_completed_command(bd); | |
175 | if (bc) | |
176 | break; | |
177 | ||
178 | if (!block) | |
179 | break; | |
180 | ||
181 | ret = wait_event_interruptible(bd->wq_done, bd->done_cmds); | |
182 | if (ret) { | |
183 | bc = ERR_PTR(-ERESTARTSYS); | |
184 | break; | |
185 | } | |
186 | } while (1); | |
187 | ||
188 | return bc; | |
189 | } | |
190 | ||
191 | static void bc_put_bio_pages(struct bio *bio) | |
192 | { | |
193 | struct bio_vec *bv; | |
194 | unsigned int i; | |
195 | ||
196 | __bio_for_each_segment(bv, bio, i, 0) { | |
197 | if (bv->bv_page != ZERO_PAGE(0)) | |
198 | __free_page(bv->bv_page); | |
199 | } | |
200 | } | |
201 | ||
202 | static void complete_and_free_bio(struct b_cmd *bc) | |
203 | { | |
204 | if (bc->bio) { | |
205 | const struct uc_map *ucm = &uc_map[bc->cmd.type]; | |
206 | ||
207 | if (ucm->data_transfer) { | |
208 | if (!ucm->map_zero) | |
209 | bio_unmap_user(bc->bio); | |
210 | else | |
211 | bc_put_bio_pages(bc->bio); | |
212 | } | |
213 | bio_put(bc->bio); | |
214 | bc->bio = NULL; | |
215 | } | |
216 | } | |
217 | ||
218 | static void b_dev_complete_commands(struct b_dev *bd) | |
219 | { | |
220 | struct b_cmd *bc; | |
221 | ||
222 | wait_event(bd->wq_done, !atomic_read(&bd->in_flight)); | |
223 | ||
224 | while ((bc = get_completed_command(bd)) != NULL) | |
225 | complete_and_free_bio(bc); | |
226 | } | |
227 | ||
228 | static int b_dev_validate_command(struct b_user_cmd *buc) | |
229 | { | |
230 | if (!binject_buc_check_magic(buc)) | |
231 | return -EINVAL; | |
232 | ||
233 | switch (buc->type) { | |
234 | case B_TYPE_WRITE: | |
235 | case B_TYPE_READ: | |
236 | case B_TYPE_DISCARD: | |
237 | case B_TYPE_READVOID: | |
238 | case B_TYPE_WRITEZERO: | |
239 | if (buc->len) | |
240 | return 0; | |
241 | return -EINVAL; | |
242 | default: | |
243 | return -EINVAL; | |
244 | } | |
245 | } | |
246 | ||
247 | static void b_cmd_endio(struct bio *bio, int error) | |
248 | { | |
249 | struct b_cmd *bc = bio->bi_private; | |
250 | struct b_dev *bd = bc->bd; | |
251 | unsigned long flags; | |
252 | unsigned long now; | |
253 | ||
254 | now = ktime_to_ns(ktime_get()); | |
255 | bc->cmd.nsec = now - bc->issue_time; | |
256 | bc->cmd.error = error; | |
257 | ||
258 | spin_lock_irqsave(&bd->lock, flags); | |
259 | list_add_tail(&bc->list, &bd->done_list); | |
260 | bd->done_cmds++; | |
261 | spin_unlock_irqrestore(&bd->lock, flags); | |
262 | ||
263 | atomic_dec(&bd->in_flight); | |
264 | ||
265 | wake_up(&bd->wq_done); | |
266 | } | |
267 | ||
268 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 18) | |
269 | static int bio_cmd_endio(struct bio *bio, unsigned int bytes, int err) | |
270 | { | |
271 | if (bio->bi_size) | |
272 | return 1; | |
273 | ||
274 | b_cmd_endio(bio, err); | |
275 | return 0; | |
276 | } | |
277 | #else | |
278 | static void bio_cmd_endio(struct bio *bio, int err) | |
279 | { | |
280 | b_cmd_endio(bio, err); | |
281 | } | |
282 | #endif | |
283 | ||
284 | static int zero_map_bio(struct request_queue *q, struct bio *bio, | |
285 | const struct uc_map *ucm, unsigned int len) | |
286 | { | |
287 | unsigned int i, nr_pages, this_len, ret, err; | |
288 | struct page *page; | |
289 | ||
290 | nr_pages = len / PAGE_SIZE; | |
291 | for (i = 0; i < nr_pages; i++) { | |
292 | if (ucm->todevice) | |
293 | page = ZERO_PAGE(0); | |
294 | else { | |
295 | page = alloc_page(GFP_KERNEL); | |
296 | if (!page) { | |
297 | err = -ENOMEM; | |
298 | goto oom; | |
299 | } | |
300 | } | |
301 | ||
302 | this_len = PAGE_SIZE; | |
303 | if (this_len > len) | |
304 | this_len = len; | |
305 | ||
306 | ret = bio_add_pc_page(q, bio, page, len, 0); | |
307 | if (ret < len) { | |
308 | err = -E2BIG; | |
309 | goto oom; | |
310 | } | |
311 | } | |
312 | return 0; | |
313 | oom: | |
314 | bc_put_bio_pages(bio); | |
315 | return err; | |
316 | } | |
317 | ||
318 | static void map_uc_to_bio_flags(struct bio *bio, struct b_user_cmd *uc) | |
319 | { | |
320 | unsigned int i; | |
321 | ||
322 | for (i = 0; i < 8 * sizeof(uc->flags); i++) { | |
323 | unsigned long mask; | |
324 | ||
325 | if (uc->flags & (1UL << i)) | |
326 | bio->bi_rw |= uc_flag_map[i]; | |
327 | ||
328 | mask = ~((1UL << i) - 1); | |
329 | if (!(mask & uc->flags)) | |
330 | break; | |
331 | } | |
332 | } | |
333 | ||
334 | static struct bio *map_uc_to_bio(struct b_dev *bd, struct b_user_cmd *uc) | |
335 | { | |
336 | struct request_queue *q = bdev_get_queue(bd->bdev); | |
337 | const struct uc_map *ucm = &uc_map[uc->type]; | |
338 | struct bio *bio; | |
339 | ||
340 | if (ucm->data_transfer && !ucm->map_zero) { | |
341 | bio = binject_map_bio(q, bd->bdev, uc->buf, uc->len, | |
342 | !ucm->todevice, GFP_KERNEL); | |
343 | } else { | |
344 | bio = bio_alloc(GFP_KERNEL, uc->len / PAGE_SIZE); | |
345 | if (bio) { | |
346 | bio->bi_bdev = bd->bdev; | |
347 | if (ucm->todevice) | |
348 | binject_mark_bio_write(bio); | |
349 | if (ucm->map_zero && uc->len) { | |
350 | int err; | |
351 | ||
352 | err = zero_map_bio(q, bio, ucm, uc->len); | |
353 | if (err) { | |
354 | bio_put(bio); | |
355 | bio = ERR_PTR(err); | |
356 | } | |
357 | } else | |
358 | bio->bi_size = uc->len; | |
359 | } | |
360 | } | |
361 | ||
362 | if (!bio) | |
363 | bio = ERR_PTR(-ENOMEM); | |
364 | else if (!IS_ERR(bio)) { | |
365 | map_uc_to_bio_flags(bio, uc); | |
366 | bio->bi_sector = uc->offset / binject_get_bs(q); | |
367 | } | |
368 | ||
369 | return bio; | |
370 | } | |
371 | ||
372 | static int b_dev_add_command(struct b_dev *bd, struct b_cmd *bc) | |
373 | { | |
374 | struct b_user_cmd *uc = &bc->cmd; | |
375 | struct bio *bio; | |
376 | ||
377 | bio = map_uc_to_bio(bd, uc); | |
378 | if (IS_ERR(bio)) | |
379 | return PTR_ERR(bio); | |
380 | ||
381 | bio_get(bio); | |
382 | bc->bio = bio; | |
383 | ||
384 | bio->bi_end_io = bio_cmd_endio; | |
385 | bio->bi_private = bc; | |
386 | ||
387 | bc->issue_time = ktime_to_ns(ktime_get()); | |
388 | ||
389 | atomic_inc(&bd->in_flight); | |
390 | submit_bio(bio->bi_rw, bio); | |
391 | return 0; | |
392 | } | |
393 | ||
394 | static void b_dev_free_command(struct b_dev *bd, struct b_cmd *bc) | |
395 | { | |
396 | kmem_cache_free(b_slab, bc); | |
397 | } | |
398 | ||
399 | /* | |
400 | * We are always writable, as we have an infinite queue depth | |
401 | */ | |
402 | static unsigned int b_dev_poll(struct file *file, poll_table *wait) | |
403 | { | |
404 | struct b_dev *bd = file->private_data; | |
405 | unsigned int mask = POLLOUT; | |
406 | ||
407 | poll_wait(file, &bd->wq_done, wait); | |
408 | ||
409 | spin_lock_irq(&bd->lock); | |
410 | if (!list_empty(&bd->done_list)) | |
411 | mask |= POLLIN | POLLRDNORM; | |
412 | spin_unlock_irq(&bd->lock); | |
413 | ||
414 | return mask; | |
415 | } | |
416 | ||
417 | static int b_dev_release(struct inode *inode, struct file *file) | |
418 | { | |
419 | struct b_dev *bd = file->private_data; | |
420 | ||
421 | b_dev_put(bd); | |
422 | return 0; | |
423 | } | |
424 | ||
425 | static struct b_dev *b_dev_lookup(int minor) | |
426 | { | |
427 | struct b_dev *bd; | |
428 | ||
429 | rcu_read_lock(); | |
430 | bd = idr_find(&b_minor_idr, minor); | |
431 | if (bd) { | |
432 | if (!atomic_inc_not_zero(&bd->ref)) | |
433 | bd = NULL; | |
434 | } | |
435 | rcu_read_unlock(); | |
436 | ||
437 | return bd; | |
438 | } | |
439 | ||
440 | static int b_dev_open(struct inode *inode, struct file *file) | |
441 | { | |
442 | struct b_dev *bd; | |
443 | ||
444 | bd = b_dev_lookup(iminor(inode)); | |
445 | if (!bd) | |
446 | return -ENODEV; | |
447 | ||
448 | file->private_data = bd; | |
449 | return 0; | |
450 | } | |
451 | ||
452 | static ssize_t b_dev_write(struct file *file, const char __user *buf, | |
453 | size_t count, loff_t *ppos) | |
454 | { | |
455 | struct b_dev *bd = file->private_data; | |
456 | unsigned int total; | |
457 | ssize_t done = 0; | |
458 | int err = 0; | |
459 | ||
460 | if (count % sizeof(struct b_user_cmd)) | |
461 | return -EINVAL; | |
462 | ||
463 | total = count / sizeof(struct b_user_cmd); | |
464 | while (total) { | |
465 | struct b_cmd *bc; | |
466 | ||
467 | bc = get_free_command(bd); | |
468 | if (IS_ERR(bc)) { | |
469 | err = PTR_ERR(bc); | |
470 | break; | |
471 | } | |
472 | ||
473 | if (copy_from_user(&bc->cmd, buf, sizeof(struct b_user_cmd))) { | |
474 | err = -EFAULT; | |
475 | break; | |
476 | } | |
477 | ||
478 | err = b_dev_validate_command(&bc->cmd); | |
479 | if (err) { | |
480 | b_dev_free_command(bd, bc); | |
481 | break; | |
482 | } | |
483 | ||
484 | err = b_dev_add_command(bd, bc); | |
485 | if (err) { | |
486 | b_dev_free_command(bd, bc); | |
487 | break; | |
488 | } | |
489 | ||
490 | done += sizeof(struct b_user_cmd); | |
491 | buf += sizeof(struct b_user_cmd); | |
492 | total--; | |
493 | } | |
494 | ||
495 | *ppos = done; | |
496 | if (!done) | |
497 | done = err; | |
498 | ||
499 | return done; | |
500 | } | |
501 | ||
502 | static ssize_t b_dev_read(struct file *file, char __user *buf, size_t count, | |
503 | loff_t *ppos) | |
504 | { | |
505 | struct b_dev *bd = file->private_data; | |
506 | unsigned int total; | |
507 | ssize_t done = 0; | |
508 | int err = 0; | |
509 | ||
510 | if (count % sizeof(struct b_user_cmd)) | |
511 | return -EINVAL; | |
512 | ||
513 | total = count / sizeof(struct b_user_cmd); | |
514 | while (total) { | |
515 | struct b_cmd *bc; | |
516 | ||
517 | bc = get_done_command(bd, !(file->f_flags & O_NONBLOCK)); | |
518 | if (IS_ERR(bc)) { | |
519 | err = PTR_ERR(bc); | |
520 | break; | |
521 | } | |
522 | ||
523 | complete_and_free_bio(bc); | |
524 | ||
525 | if (copy_to_user(buf, &bc->cmd, sizeof(bc->cmd))) | |
526 | err = -EFAULT; | |
527 | ||
528 | b_dev_free_command(bd, bc); | |
529 | ||
530 | if (err) | |
531 | break; | |
532 | ||
533 | done += sizeof(struct b_user_cmd); | |
534 | buf += sizeof(struct b_user_cmd); | |
535 | total--; | |
536 | } | |
537 | ||
538 | *ppos = done; | |
539 | if (!done) | |
540 | done = err; | |
541 | ||
542 | return done; | |
543 | } | |
544 | ||
545 | static const struct file_operations b_dev_fops = { | |
546 | .open = b_dev_open, | |
547 | .release = b_dev_release, | |
548 | .read = b_dev_read, | |
549 | .write = b_dev_write, | |
550 | .poll = b_dev_poll, | |
551 | .owner = THIS_MODULE, | |
552 | }; | |
553 | ||
554 | static int b_del_dev(struct b_ioctl_cmd *bic) | |
555 | { | |
556 | struct b_dev *bd; | |
557 | ||
558 | bd = b_dev_lookup(bic->minor); | |
559 | if (bd) { | |
560 | spin_lock(&b_dev_lock); | |
561 | b_dev_remove_lookup(bd); | |
562 | spin_unlock(&b_dev_lock); | |
563 | ||
564 | /* | |
565 | * Our lookup grabbed a reference, drop two | |
566 | */ | |
567 | b_dev_put(bd); | |
568 | b_dev_put(bd); | |
569 | return 0; | |
570 | } | |
571 | ||
572 | return -ENODEV; | |
573 | } | |
574 | ||
575 | static int b_add_dev(struct b_ioctl_cmd *bic) | |
576 | { | |
577 | struct inode *inode; | |
578 | struct file *file; | |
579 | struct b_dev *bd; | |
580 | int ret; | |
581 | ||
582 | file = fget(bic->fd); | |
583 | if (!file) | |
584 | return -EBADF; | |
585 | ||
586 | __module_get(THIS_MODULE); | |
587 | ||
588 | inode = file->f_mapping->host; | |
589 | if (!S_ISBLK(inode->i_mode)) { | |
590 | ret = -EINVAL; | |
591 | goto out_put; | |
592 | } | |
593 | ||
594 | ret = idr_pre_get(&b_minor_idr, GFP_KERNEL); | |
595 | if (!ret) { | |
596 | ret = -ENOMEM; | |
597 | goto out_put; | |
598 | } | |
599 | ||
600 | bd = kzalloc(sizeof(*bd), GFP_KERNEL); | |
601 | if (!bd) { | |
602 | ret = -ENOMEM; | |
603 | goto out_put; | |
604 | } | |
605 | ||
606 | atomic_set(&bd->ref, 1); | |
607 | spin_lock_init(&bd->lock); | |
608 | INIT_LIST_HEAD(&bd->done_list); | |
609 | init_waitqueue_head(&bd->wq_done); | |
610 | bd->file = file; | |
611 | bd->bdev = inode->i_bdev;; | |
612 | ||
613 | spin_lock(&b_dev_lock); | |
614 | ||
615 | ret = idr_get_new(&b_minor_idr, bd, &bd->minor); | |
616 | if (ret < 0) | |
617 | goto out_unlock; | |
618 | ||
619 | if (bd->minor >= B_MAX_DEVS) | |
620 | goto out_idr; | |
621 | ||
622 | spin_unlock(&b_dev_lock); | |
623 | ||
624 | INIT_LIST_HEAD(&bd->device_list); | |
625 | bd->dev = binject_device_create(b_class, NULL, | |
626 | MKDEV(b_major, bd->minor), bd, "binject%d", bd->minor); | |
627 | ||
628 | spin_lock(&b_dev_lock); | |
629 | ||
630 | if (IS_ERR(bd->dev)) | |
631 | goto out_idr; | |
632 | ||
633 | list_add_tail(&bd->device_list, &b_dev_list); | |
634 | spin_unlock(&b_dev_lock); | |
635 | return 0; | |
636 | out_idr: | |
637 | idr_remove(&b_minor_idr, bd->minor); | |
638 | out_unlock: | |
639 | spin_unlock(&b_dev_lock); | |
640 | kfree(bd); | |
641 | out_put: | |
642 | fput(file); | |
643 | module_put(THIS_MODULE); | |
644 | return ret; | |
645 | } | |
646 | ||
647 | static long b_misc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) | |
648 | { | |
649 | int __user *uarg = (int __user *) arg; | |
650 | struct b_ioctl_cmd bic; | |
651 | ||
652 | if (copy_from_user(&bic, uarg, sizeof(bic))) | |
653 | return -EFAULT; | |
654 | ||
655 | switch (cmd) { | |
656 | case 0: | |
657 | return b_add_dev(&bic); | |
658 | case 1: | |
659 | return b_del_dev(&bic); | |
660 | default: | |
661 | break; | |
662 | } | |
663 | ||
664 | return -ENOTTY; | |
665 | } | |
666 | ||
667 | static const struct file_operations b_misc_fops = { | |
668 | .unlocked_ioctl = b_misc_ioctl, | |
669 | .owner = THIS_MODULE, | |
670 | }; | |
671 | ||
672 | static struct miscdevice b_misc_dev = { | |
673 | .minor = MISC_DYNAMIC_MINOR, | |
674 | .name = "binject-ctl", | |
675 | .fops = &b_misc_fops, | |
676 | }; | |
677 | ||
678 | static void __exit b_exit(void) | |
679 | { | |
680 | synchronize_rcu(); | |
681 | kmem_cache_destroy(b_slab); | |
682 | class_destroy(b_class); | |
683 | misc_deregister(&b_misc_dev); | |
684 | } | |
685 | ||
686 | static int __init b_init(void) | |
687 | { | |
688 | int ret; | |
689 | ||
690 | b_slab = binject_create_slab("binject", sizeof(struct b_cmd)); | |
691 | if (!b_slab) { | |
692 | printk(KERN_ERR "binject: failed to create cmd slab\n"); | |
693 | return -ENOMEM; | |
694 | } | |
695 | ||
696 | ret = misc_register(&b_misc_dev); | |
697 | if (ret < 0) | |
698 | goto fail_misc; | |
699 | ||
700 | b_major = register_chrdev(0, "binject", &b_dev_fops); | |
701 | if (b_major < 0) | |
702 | goto fail_chr; | |
703 | ||
704 | b_class = class_create(THIS_MODULE, "binject"); | |
705 | if (IS_ERR(b_class)) | |
706 | goto fail_class; | |
707 | ||
708 | return 0; | |
709 | fail_class: | |
710 | unregister_chrdev(b_major, "binject"); | |
711 | fail_chr: | |
712 | misc_deregister(&b_misc_dev); | |
713 | fail_misc: | |
714 | kmem_cache_destroy(b_slab); | |
715 | return ret; | |
716 | } | |
717 | ||
718 | module_init(b_init); | |
719 | module_exit(b_exit); | |
720 | ||
721 | MODULE_LICENSE("GPL"); | |
722 | MODULE_AUTHOR("Jens Axboe <jaxboe@fusionio.com>"); |