Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2002 Sistina Software (UK) Limited. | |
373a392b | 3 | * Copyright (C) 2006 Red Hat GmbH |
1da177e4 LT |
4 | * |
5 | * This file is released under the GPL. | |
6 | * | |
7 | * Kcopyd provides a simple interface for copying an area of one | |
8 | * block-device to one or more other block-devices, with an asynchronous | |
9 | * completion notification. | |
10 | */ | |
11 | ||
eb69aca5 | 12 | #include <linux/types.h> |
1da177e4 | 13 | #include <asm/atomic.h> |
1da177e4 | 14 | #include <linux/blkdev.h> |
1da177e4 LT |
15 | #include <linux/fs.h> |
16 | #include <linux/init.h> | |
17 | #include <linux/list.h> | |
18 | #include <linux/mempool.h> | |
19 | #include <linux/module.h> | |
20 | #include <linux/pagemap.h> | |
21 | #include <linux/slab.h> | |
22 | #include <linux/vmalloc.h> | |
23 | #include <linux/workqueue.h> | |
48c9c27b | 24 | #include <linux/mutex.h> |
a765e20e | 25 | #include <linux/dm-kcopyd.h> |
1da177e4 | 26 | |
22a1ceb1 | 27 | #include "dm.h" |
1da177e4 | 28 | |
1da177e4 LT |
29 | /*----------------------------------------------------------------- |
30 | * Each kcopyd client has its own little pool of preallocated | |
31 | * pages for kcopyd io. | |
32 | *---------------------------------------------------------------*/ | |
eb69aca5 | 33 | struct dm_kcopyd_client { |
1da177e4 LT |
34 | spinlock_t lock; |
35 | struct page_list *pages; | |
36 | unsigned int nr_pages; | |
37 | unsigned int nr_free_pages; | |
138728dc | 38 | |
373a392b MB |
39 | struct dm_io_client *io_client; |
40 | ||
138728dc AK |
41 | wait_queue_head_t destroyq; |
42 | atomic_t nr_jobs; | |
8c0cbc2f | 43 | |
08d8757a MP |
44 | mempool_t *job_pool; |
45 | ||
8c0cbc2f MP |
46 | struct workqueue_struct *kcopyd_wq; |
47 | struct work_struct kcopyd_work; | |
48 | ||
49 | /* | |
50 | * We maintain three lists of jobs: | |
51 | * | |
52 | * i) jobs waiting for pages | |
53 | * ii) jobs that have pages, and are waiting for the io to be issued. | |
54 | * iii) jobs that have completed. | |
55 | * | |
56 | * All three of these are protected by job_lock. | |
57 | */ | |
58 | spinlock_t job_lock; | |
59 | struct list_head complete_jobs; | |
60 | struct list_head io_jobs; | |
61 | struct list_head pages_jobs; | |
1da177e4 LT |
62 | }; |
63 | ||
8c0cbc2f MP |
64 | static void wake(struct dm_kcopyd_client *kc) |
65 | { | |
66 | queue_work(kc->kcopyd_wq, &kc->kcopyd_work); | |
67 | } | |
68 | ||
1da177e4 LT |
69 | static struct page_list *alloc_pl(void) |
70 | { | |
71 | struct page_list *pl; | |
72 | ||
73 | pl = kmalloc(sizeof(*pl), GFP_KERNEL); | |
74 | if (!pl) | |
75 | return NULL; | |
76 | ||
77 | pl->page = alloc_page(GFP_KERNEL); | |
78 | if (!pl->page) { | |
79 | kfree(pl); | |
80 | return NULL; | |
81 | } | |
82 | ||
83 | return pl; | |
84 | } | |
85 | ||
86 | static void free_pl(struct page_list *pl) | |
87 | { | |
88 | __free_page(pl->page); | |
89 | kfree(pl); | |
90 | } | |
91 | ||
eb69aca5 | 92 | static int kcopyd_get_pages(struct dm_kcopyd_client *kc, |
1da177e4 LT |
93 | unsigned int nr, struct page_list **pages) |
94 | { | |
95 | struct page_list *pl; | |
96 | ||
97 | spin_lock(&kc->lock); | |
98 | if (kc->nr_free_pages < nr) { | |
99 | spin_unlock(&kc->lock); | |
100 | return -ENOMEM; | |
101 | } | |
102 | ||
103 | kc->nr_free_pages -= nr; | |
104 | for (*pages = pl = kc->pages; --nr; pl = pl->next) | |
105 | ; | |
106 | ||
107 | kc->pages = pl->next; | |
108 | pl->next = NULL; | |
109 | ||
110 | spin_unlock(&kc->lock); | |
111 | ||
112 | return 0; | |
113 | } | |
114 | ||
eb69aca5 | 115 | static void kcopyd_put_pages(struct dm_kcopyd_client *kc, struct page_list *pl) |
1da177e4 LT |
116 | { |
117 | struct page_list *cursor; | |
118 | ||
119 | spin_lock(&kc->lock); | |
120 | for (cursor = pl; cursor->next; cursor = cursor->next) | |
121 | kc->nr_free_pages++; | |
122 | ||
123 | kc->nr_free_pages++; | |
124 | cursor->next = kc->pages; | |
125 | kc->pages = pl; | |
126 | spin_unlock(&kc->lock); | |
127 | } | |
128 | ||
129 | /* | |
130 | * These three functions resize the page pool. | |
131 | */ | |
132 | static void drop_pages(struct page_list *pl) | |
133 | { | |
134 | struct page_list *next; | |
135 | ||
136 | while (pl) { | |
137 | next = pl->next; | |
138 | free_pl(pl); | |
139 | pl = next; | |
140 | } | |
141 | } | |
142 | ||
eb69aca5 | 143 | static int client_alloc_pages(struct dm_kcopyd_client *kc, unsigned int nr) |
1da177e4 LT |
144 | { |
145 | unsigned int i; | |
146 | struct page_list *pl = NULL, *next; | |
147 | ||
148 | for (i = 0; i < nr; i++) { | |
149 | next = alloc_pl(); | |
150 | if (!next) { | |
151 | if (pl) | |
152 | drop_pages(pl); | |
153 | return -ENOMEM; | |
154 | } | |
155 | next->next = pl; | |
156 | pl = next; | |
157 | } | |
158 | ||
159 | kcopyd_put_pages(kc, pl); | |
160 | kc->nr_pages += nr; | |
161 | return 0; | |
162 | } | |
163 | ||
eb69aca5 | 164 | static void client_free_pages(struct dm_kcopyd_client *kc) |
1da177e4 LT |
165 | { |
166 | BUG_ON(kc->nr_free_pages != kc->nr_pages); | |
167 | drop_pages(kc->pages); | |
168 | kc->pages = NULL; | |
169 | kc->nr_free_pages = kc->nr_pages = 0; | |
170 | } | |
171 | ||
172 | /*----------------------------------------------------------------- | |
173 | * kcopyd_jobs need to be allocated by the *clients* of kcopyd, | |
174 | * for this reason we use a mempool to prevent the client from | |
175 | * ever having to do io (which could cause a deadlock). | |
176 | *---------------------------------------------------------------*/ | |
177 | struct kcopyd_job { | |
eb69aca5 | 178 | struct dm_kcopyd_client *kc; |
1da177e4 LT |
179 | struct list_head list; |
180 | unsigned long flags; | |
181 | ||
182 | /* | |
183 | * Error state of the job. | |
184 | */ | |
185 | int read_err; | |
4cdc1d1f | 186 | unsigned long write_err; |
1da177e4 LT |
187 | |
188 | /* | |
189 | * Either READ or WRITE | |
190 | */ | |
191 | int rw; | |
22a1ceb1 | 192 | struct dm_io_region source; |
1da177e4 LT |
193 | |
194 | /* | |
195 | * The destinations for the transfer. | |
196 | */ | |
197 | unsigned int num_dests; | |
eb69aca5 | 198 | struct dm_io_region dests[DM_KCOPYD_MAX_REGIONS]; |
1da177e4 LT |
199 | |
200 | sector_t offset; | |
201 | unsigned int nr_pages; | |
202 | struct page_list *pages; | |
203 | ||
204 | /* | |
205 | * Set this to ensure you are notified when the job has | |
206 | * completed. 'context' is for callback to use. | |
207 | */ | |
eb69aca5 | 208 | dm_kcopyd_notify_fn fn; |
1da177e4 LT |
209 | void *context; |
210 | ||
211 | /* | |
212 | * These fields are only used if the job has been split | |
213 | * into more manageable parts. | |
214 | */ | |
def5b5b2 | 215 | struct mutex lock; |
1da177e4 LT |
216 | atomic_t sub_jobs; |
217 | sector_t progress; | |
218 | }; | |
219 | ||
220 | /* FIXME: this should scale with the number of pages */ | |
221 | #define MIN_JOBS 512 | |
222 | ||
e18b890b | 223 | static struct kmem_cache *_job_cache; |
1da177e4 | 224 | |
945fa4d2 | 225 | int __init dm_kcopyd_init(void) |
1da177e4 | 226 | { |
028867ac | 227 | _job_cache = KMEM_CACHE(kcopyd_job, 0); |
1da177e4 LT |
228 | if (!_job_cache) |
229 | return -ENOMEM; | |
230 | ||
1da177e4 LT |
231 | return 0; |
232 | } | |
233 | ||
945fa4d2 | 234 | void dm_kcopyd_exit(void) |
1da177e4 | 235 | { |
1da177e4 | 236 | kmem_cache_destroy(_job_cache); |
1da177e4 LT |
237 | _job_cache = NULL; |
238 | } | |
239 | ||
240 | /* | |
241 | * Functions to push and pop a job onto the head of a given job | |
242 | * list. | |
243 | */ | |
8c0cbc2f MP |
244 | static struct kcopyd_job *pop(struct list_head *jobs, |
245 | struct dm_kcopyd_client *kc) | |
1da177e4 LT |
246 | { |
247 | struct kcopyd_job *job = NULL; | |
248 | unsigned long flags; | |
249 | ||
8c0cbc2f | 250 | spin_lock_irqsave(&kc->job_lock, flags); |
1da177e4 LT |
251 | |
252 | if (!list_empty(jobs)) { | |
253 | job = list_entry(jobs->next, struct kcopyd_job, list); | |
254 | list_del(&job->list); | |
255 | } | |
8c0cbc2f | 256 | spin_unlock_irqrestore(&kc->job_lock, flags); |
1da177e4 LT |
257 | |
258 | return job; | |
259 | } | |
260 | ||
028867ac | 261 | static void push(struct list_head *jobs, struct kcopyd_job *job) |
1da177e4 LT |
262 | { |
263 | unsigned long flags; | |
8c0cbc2f | 264 | struct dm_kcopyd_client *kc = job->kc; |
1da177e4 | 265 | |
8c0cbc2f | 266 | spin_lock_irqsave(&kc->job_lock, flags); |
1da177e4 | 267 | list_add_tail(&job->list, jobs); |
8c0cbc2f | 268 | spin_unlock_irqrestore(&kc->job_lock, flags); |
1da177e4 LT |
269 | } |
270 | ||
b673c3a8 KI |
271 | |
272 | static void push_head(struct list_head *jobs, struct kcopyd_job *job) | |
273 | { | |
274 | unsigned long flags; | |
275 | struct dm_kcopyd_client *kc = job->kc; | |
276 | ||
277 | spin_lock_irqsave(&kc->job_lock, flags); | |
278 | list_add(&job->list, jobs); | |
279 | spin_unlock_irqrestore(&kc->job_lock, flags); | |
280 | } | |
281 | ||
1da177e4 LT |
282 | /* |
283 | * These three functions process 1 item from the corresponding | |
284 | * job list. | |
285 | * | |
286 | * They return: | |
287 | * < 0: error | |
288 | * 0: success | |
289 | * > 0: can't process yet. | |
290 | */ | |
291 | static int run_complete_job(struct kcopyd_job *job) | |
292 | { | |
293 | void *context = job->context; | |
294 | int read_err = job->read_err; | |
4cdc1d1f | 295 | unsigned long write_err = job->write_err; |
eb69aca5 HM |
296 | dm_kcopyd_notify_fn fn = job->fn; |
297 | struct dm_kcopyd_client *kc = job->kc; | |
1da177e4 | 298 | |
138728dc | 299 | kcopyd_put_pages(kc, job->pages); |
08d8757a | 300 | mempool_free(job, kc->job_pool); |
1da177e4 | 301 | fn(read_err, write_err, context); |
138728dc AK |
302 | |
303 | if (atomic_dec_and_test(&kc->nr_jobs)) | |
304 | wake_up(&kc->destroyq); | |
305 | ||
1da177e4 LT |
306 | return 0; |
307 | } | |
308 | ||
309 | static void complete_io(unsigned long error, void *context) | |
310 | { | |
311 | struct kcopyd_job *job = (struct kcopyd_job *) context; | |
8c0cbc2f | 312 | struct dm_kcopyd_client *kc = job->kc; |
1da177e4 LT |
313 | |
314 | if (error) { | |
315 | if (job->rw == WRITE) | |
ce503f59 | 316 | job->write_err |= error; |
1da177e4 LT |
317 | else |
318 | job->read_err = 1; | |
319 | ||
eb69aca5 | 320 | if (!test_bit(DM_KCOPYD_IGNORE_ERROR, &job->flags)) { |
8c0cbc2f MP |
321 | push(&kc->complete_jobs, job); |
322 | wake(kc); | |
1da177e4 LT |
323 | return; |
324 | } | |
325 | } | |
326 | ||
327 | if (job->rw == WRITE) | |
8c0cbc2f | 328 | push(&kc->complete_jobs, job); |
1da177e4 LT |
329 | |
330 | else { | |
331 | job->rw = WRITE; | |
8c0cbc2f | 332 | push(&kc->io_jobs, job); |
1da177e4 LT |
333 | } |
334 | ||
8c0cbc2f | 335 | wake(kc); |
1da177e4 LT |
336 | } |
337 | ||
338 | /* | |
339 | * Request io on as many buffer heads as we can currently get for | |
340 | * a particular job. | |
341 | */ | |
342 | static int run_io_job(struct kcopyd_job *job) | |
343 | { | |
344 | int r; | |
373a392b | 345 | struct dm_io_request io_req = { |
7ff14a36 | 346 | .bi_rw = job->rw | (1 << BIO_RW_SYNC), |
373a392b MB |
347 | .mem.type = DM_IO_PAGE_LIST, |
348 | .mem.ptr.pl = job->pages, | |
349 | .mem.offset = job->offset, | |
350 | .notify.fn = complete_io, | |
351 | .notify.context = job, | |
352 | .client = job->kc->io_client, | |
353 | }; | |
1da177e4 LT |
354 | |
355 | if (job->rw == READ) | |
373a392b | 356 | r = dm_io(&io_req, 1, &job->source, NULL); |
1da177e4 | 357 | else |
373a392b | 358 | r = dm_io(&io_req, job->num_dests, job->dests, NULL); |
1da177e4 LT |
359 | |
360 | return r; | |
361 | } | |
362 | ||
363 | static int run_pages_job(struct kcopyd_job *job) | |
364 | { | |
365 | int r; | |
366 | ||
367 | job->nr_pages = dm_div_up(job->dests[0].count + job->offset, | |
368 | PAGE_SIZE >> 9); | |
369 | r = kcopyd_get_pages(job->kc, job->nr_pages, &job->pages); | |
370 | if (!r) { | |
371 | /* this job is ready for io */ | |
8c0cbc2f | 372 | push(&job->kc->io_jobs, job); |
1da177e4 LT |
373 | return 0; |
374 | } | |
375 | ||
376 | if (r == -ENOMEM) | |
377 | /* can't complete now */ | |
378 | return 1; | |
379 | ||
380 | return r; | |
381 | } | |
382 | ||
383 | /* | |
384 | * Run through a list for as long as possible. Returns the count | |
385 | * of successful jobs. | |
386 | */ | |
8c0cbc2f MP |
387 | static int process_jobs(struct list_head *jobs, struct dm_kcopyd_client *kc, |
388 | int (*fn) (struct kcopyd_job *)) | |
1da177e4 LT |
389 | { |
390 | struct kcopyd_job *job; | |
391 | int r, count = 0; | |
392 | ||
8c0cbc2f | 393 | while ((job = pop(jobs, kc))) { |
1da177e4 LT |
394 | |
395 | r = fn(job); | |
396 | ||
397 | if (r < 0) { | |
398 | /* error this rogue job */ | |
399 | if (job->rw == WRITE) | |
4cdc1d1f | 400 | job->write_err = (unsigned long) -1L; |
1da177e4 LT |
401 | else |
402 | job->read_err = 1; | |
8c0cbc2f | 403 | push(&kc->complete_jobs, job); |
1da177e4 LT |
404 | break; |
405 | } | |
406 | ||
407 | if (r > 0) { | |
408 | /* | |
409 | * We couldn't service this job ATM, so | |
410 | * push this job back onto the list. | |
411 | */ | |
b673c3a8 | 412 | push_head(jobs, job); |
1da177e4 LT |
413 | break; |
414 | } | |
415 | ||
416 | count++; | |
417 | } | |
418 | ||
419 | return count; | |
420 | } | |
421 | ||
422 | /* | |
423 | * kcopyd does this every time it's woken up. | |
424 | */ | |
8c0cbc2f | 425 | static void do_work(struct work_struct *work) |
1da177e4 | 426 | { |
8c0cbc2f MP |
427 | struct dm_kcopyd_client *kc = container_of(work, |
428 | struct dm_kcopyd_client, kcopyd_work); | |
429 | ||
1da177e4 LT |
430 | /* |
431 | * The order that these are called is *very* important. | |
432 | * complete jobs can free some pages for pages jobs. | |
433 | * Pages jobs when successful will jump onto the io jobs | |
434 | * list. io jobs call wake when they complete and it all | |
435 | * starts again. | |
436 | */ | |
8c0cbc2f MP |
437 | process_jobs(&kc->complete_jobs, kc, run_complete_job); |
438 | process_jobs(&kc->pages_jobs, kc, run_pages_job); | |
439 | process_jobs(&kc->io_jobs, kc, run_io_job); | |
1da177e4 LT |
440 | } |
441 | ||
442 | /* | |
443 | * If we are copying a small region we just dispatch a single job | |
444 | * to do the copy, otherwise the io has to be split up into many | |
445 | * jobs. | |
446 | */ | |
447 | static void dispatch_job(struct kcopyd_job *job) | |
448 | { | |
8c0cbc2f MP |
449 | struct dm_kcopyd_client *kc = job->kc; |
450 | atomic_inc(&kc->nr_jobs); | |
451 | push(&kc->pages_jobs, job); | |
452 | wake(kc); | |
1da177e4 LT |
453 | } |
454 | ||
455 | #define SUB_JOB_SIZE 128 | |
4cdc1d1f AK |
456 | static void segment_complete(int read_err, unsigned long write_err, |
457 | void *context) | |
1da177e4 LT |
458 | { |
459 | /* FIXME: tidy this function */ | |
460 | sector_t progress = 0; | |
461 | sector_t count = 0; | |
462 | struct kcopyd_job *job = (struct kcopyd_job *) context; | |
463 | ||
def5b5b2 | 464 | mutex_lock(&job->lock); |
1da177e4 LT |
465 | |
466 | /* update the error */ | |
467 | if (read_err) | |
468 | job->read_err = 1; | |
469 | ||
470 | if (write_err) | |
ce503f59 | 471 | job->write_err |= write_err; |
1da177e4 LT |
472 | |
473 | /* | |
474 | * Only dispatch more work if there hasn't been an error. | |
475 | */ | |
476 | if ((!job->read_err && !job->write_err) || | |
eb69aca5 | 477 | test_bit(DM_KCOPYD_IGNORE_ERROR, &job->flags)) { |
1da177e4 LT |
478 | /* get the next chunk of work */ |
479 | progress = job->progress; | |
480 | count = job->source.count - progress; | |
481 | if (count) { | |
482 | if (count > SUB_JOB_SIZE) | |
483 | count = SUB_JOB_SIZE; | |
484 | ||
485 | job->progress += count; | |
486 | } | |
487 | } | |
def5b5b2 | 488 | mutex_unlock(&job->lock); |
1da177e4 LT |
489 | |
490 | if (count) { | |
491 | int i; | |
08d8757a MP |
492 | struct kcopyd_job *sub_job = mempool_alloc(job->kc->job_pool, |
493 | GFP_NOIO); | |
1da177e4 LT |
494 | |
495 | *sub_job = *job; | |
496 | sub_job->source.sector += progress; | |
497 | sub_job->source.count = count; | |
498 | ||
499 | for (i = 0; i < job->num_dests; i++) { | |
500 | sub_job->dests[i].sector += progress; | |
501 | sub_job->dests[i].count = count; | |
502 | } | |
503 | ||
504 | sub_job->fn = segment_complete; | |
505 | sub_job->context = job; | |
506 | dispatch_job(sub_job); | |
507 | ||
508 | } else if (atomic_dec_and_test(&job->sub_jobs)) { | |
509 | ||
510 | /* | |
511 | * To avoid a race we must keep the job around | |
512 | * until after the notify function has completed. | |
513 | * Otherwise the client may try and stop the job | |
514 | * after we've completed. | |
515 | */ | |
516 | job->fn(read_err, write_err, job->context); | |
08d8757a | 517 | mempool_free(job, job->kc->job_pool); |
1da177e4 LT |
518 | } |
519 | } | |
520 | ||
521 | /* | |
522 | * Create some little jobs that will do the move between | |
523 | * them. | |
524 | */ | |
525 | #define SPLIT_COUNT 8 | |
526 | static void split_job(struct kcopyd_job *job) | |
527 | { | |
528 | int i; | |
529 | ||
530 | atomic_set(&job->sub_jobs, SPLIT_COUNT); | |
531 | for (i = 0; i < SPLIT_COUNT; i++) | |
532 | segment_complete(0, 0u, job); | |
533 | } | |
534 | ||
eb69aca5 HM |
535 | int dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from, |
536 | unsigned int num_dests, struct dm_io_region *dests, | |
537 | unsigned int flags, dm_kcopyd_notify_fn fn, void *context) | |
1da177e4 LT |
538 | { |
539 | struct kcopyd_job *job; | |
540 | ||
541 | /* | |
542 | * Allocate a new job. | |
543 | */ | |
08d8757a | 544 | job = mempool_alloc(kc->job_pool, GFP_NOIO); |
1da177e4 LT |
545 | |
546 | /* | |
547 | * set up for the read. | |
548 | */ | |
549 | job->kc = kc; | |
550 | job->flags = flags; | |
551 | job->read_err = 0; | |
552 | job->write_err = 0; | |
553 | job->rw = READ; | |
554 | ||
555 | job->source = *from; | |
556 | ||
557 | job->num_dests = num_dests; | |
558 | memcpy(&job->dests, dests, sizeof(*dests) * num_dests); | |
559 | ||
560 | job->offset = 0; | |
561 | job->nr_pages = 0; | |
562 | job->pages = NULL; | |
563 | ||
564 | job->fn = fn; | |
565 | job->context = context; | |
566 | ||
567 | if (job->source.count < SUB_JOB_SIZE) | |
568 | dispatch_job(job); | |
569 | ||
570 | else { | |
def5b5b2 | 571 | mutex_init(&job->lock); |
1da177e4 LT |
572 | job->progress = 0; |
573 | split_job(job); | |
574 | } | |
575 | ||
576 | return 0; | |
577 | } | |
eb69aca5 | 578 | EXPORT_SYMBOL(dm_kcopyd_copy); |
1da177e4 LT |
579 | |
580 | /* | |
581 | * Cancels a kcopyd job, eg. someone might be deactivating a | |
582 | * mirror. | |
583 | */ | |
0b56306e | 584 | #if 0 |
1da177e4 LT |
585 | int kcopyd_cancel(struct kcopyd_job *job, int block) |
586 | { | |
587 | /* FIXME: finish */ | |
588 | return -1; | |
589 | } | |
0b56306e | 590 | #endif /* 0 */ |
1da177e4 LT |
591 | |
592 | /*----------------------------------------------------------------- | |
945fa4d2 | 593 | * Client setup |
1da177e4 | 594 | *---------------------------------------------------------------*/ |
eb69aca5 HM |
595 | int dm_kcopyd_client_create(unsigned int nr_pages, |
596 | struct dm_kcopyd_client **result) | |
1da177e4 | 597 | { |
945fa4d2 | 598 | int r = -ENOMEM; |
eb69aca5 | 599 | struct dm_kcopyd_client *kc; |
1da177e4 | 600 | |
1da177e4 | 601 | kc = kmalloc(sizeof(*kc), GFP_KERNEL); |
945fa4d2 MP |
602 | if (!kc) |
603 | return -ENOMEM; | |
1da177e4 LT |
604 | |
605 | spin_lock_init(&kc->lock); | |
8c0cbc2f MP |
606 | spin_lock_init(&kc->job_lock); |
607 | INIT_LIST_HEAD(&kc->complete_jobs); | |
608 | INIT_LIST_HEAD(&kc->io_jobs); | |
609 | INIT_LIST_HEAD(&kc->pages_jobs); | |
610 | ||
08d8757a | 611 | kc->job_pool = mempool_create_slab_pool(MIN_JOBS, _job_cache); |
945fa4d2 MP |
612 | if (!kc->job_pool) |
613 | goto bad_slab; | |
08d8757a | 614 | |
8c0cbc2f MP |
615 | INIT_WORK(&kc->kcopyd_work, do_work); |
616 | kc->kcopyd_wq = create_singlethread_workqueue("kcopyd"); | |
945fa4d2 MP |
617 | if (!kc->kcopyd_wq) |
618 | goto bad_workqueue; | |
8c0cbc2f | 619 | |
1da177e4 LT |
620 | kc->pages = NULL; |
621 | kc->nr_pages = kc->nr_free_pages = 0; | |
622 | r = client_alloc_pages(kc, nr_pages); | |
945fa4d2 MP |
623 | if (r) |
624 | goto bad_client_pages; | |
1da177e4 | 625 | |
373a392b MB |
626 | kc->io_client = dm_io_client_create(nr_pages); |
627 | if (IS_ERR(kc->io_client)) { | |
628 | r = PTR_ERR(kc->io_client); | |
945fa4d2 | 629 | goto bad_io_client; |
1da177e4 LT |
630 | } |
631 | ||
138728dc AK |
632 | init_waitqueue_head(&kc->destroyq); |
633 | atomic_set(&kc->nr_jobs, 0); | |
634 | ||
1da177e4 LT |
635 | *result = kc; |
636 | return 0; | |
945fa4d2 MP |
637 | |
638 | bad_io_client: | |
639 | client_free_pages(kc); | |
640 | bad_client_pages: | |
641 | destroy_workqueue(kc->kcopyd_wq); | |
642 | bad_workqueue: | |
643 | mempool_destroy(kc->job_pool); | |
644 | bad_slab: | |
645 | kfree(kc); | |
646 | ||
647 | return r; | |
1da177e4 | 648 | } |
eb69aca5 | 649 | EXPORT_SYMBOL(dm_kcopyd_client_create); |
1da177e4 | 650 | |
eb69aca5 | 651 | void dm_kcopyd_client_destroy(struct dm_kcopyd_client *kc) |
1da177e4 | 652 | { |
138728dc AK |
653 | /* Wait for completion of all jobs submitted by this client. */ |
654 | wait_event(kc->destroyq, !atomic_read(&kc->nr_jobs)); | |
655 | ||
8c0cbc2f MP |
656 | BUG_ON(!list_empty(&kc->complete_jobs)); |
657 | BUG_ON(!list_empty(&kc->io_jobs)); | |
658 | BUG_ON(!list_empty(&kc->pages_jobs)); | |
659 | destroy_workqueue(kc->kcopyd_wq); | |
373a392b | 660 | dm_io_client_destroy(kc->io_client); |
1da177e4 | 661 | client_free_pages(kc); |
08d8757a | 662 | mempool_destroy(kc->job_pool); |
1da177e4 | 663 | kfree(kc); |
1da177e4 | 664 | } |
eb69aca5 | 665 | EXPORT_SYMBOL(dm_kcopyd_client_destroy); |