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f5db4af4 JB |
1 | /* |
2 | * Copyright (C) 2006-2009 Red Hat, Inc. | |
3 | * | |
4 | * This file is released under the LGPL. | |
5 | */ | |
6 | ||
7 | #include <linux/bio.h> | |
8 | #include <linux/dm-dirty-log.h> | |
9 | #include <linux/device-mapper.h> | |
10 | #include <linux/dm-log-userspace.h> | |
11 | ||
12 | #include "dm-log-userspace-transfer.h" | |
13 | ||
14 | struct flush_entry { | |
15 | int type; | |
16 | region_t region; | |
17 | struct list_head list; | |
18 | }; | |
19 | ||
20 | struct log_c { | |
21 | struct dm_target *ti; | |
22 | uint32_t region_size; | |
23 | region_t region_count; | |
24 | char uuid[DM_UUID_LEN]; | |
25 | ||
26 | char *usr_argv_str; | |
27 | uint32_t usr_argc; | |
28 | ||
29 | /* | |
30 | * in_sync_hint gets set when doing is_remote_recovering. It | |
31 | * represents the first region that needs recovery. IOW, the | |
32 | * first zero bit of sync_bits. This can be useful for to limit | |
33 | * traffic for calls like is_remote_recovering and get_resync_work, | |
34 | * but be take care in its use for anything else. | |
35 | */ | |
36 | uint64_t in_sync_hint; | |
37 | ||
38 | spinlock_t flush_lock; | |
39 | struct list_head flush_list; /* only for clear and mark requests */ | |
40 | }; | |
41 | ||
42 | static mempool_t *flush_entry_pool; | |
43 | ||
44 | static void *flush_entry_alloc(gfp_t gfp_mask, void *pool_data) | |
45 | { | |
46 | return kmalloc(sizeof(struct flush_entry), gfp_mask); | |
47 | } | |
48 | ||
49 | static void flush_entry_free(void *element, void *pool_data) | |
50 | { | |
51 | kfree(element); | |
52 | } | |
53 | ||
54 | static int userspace_do_request(struct log_c *lc, const char *uuid, | |
55 | int request_type, char *data, size_t data_size, | |
56 | char *rdata, size_t *rdata_size) | |
57 | { | |
58 | int r; | |
59 | ||
60 | /* | |
61 | * If the server isn't there, -ESRCH is returned, | |
62 | * and we must keep trying until the server is | |
63 | * restored. | |
64 | */ | |
65 | retry: | |
66 | r = dm_consult_userspace(uuid, request_type, data, | |
67 | data_size, rdata, rdata_size); | |
68 | ||
69 | if (r != -ESRCH) | |
70 | return r; | |
71 | ||
72 | DMERR(" Userspace log server not found."); | |
73 | while (1) { | |
74 | set_current_state(TASK_INTERRUPTIBLE); | |
75 | schedule_timeout(2*HZ); | |
76 | DMWARN("Attempting to contact userspace log server..."); | |
77 | r = dm_consult_userspace(uuid, DM_ULOG_CTR, lc->usr_argv_str, | |
78 | strlen(lc->usr_argv_str) + 1, | |
79 | NULL, NULL); | |
80 | if (!r) | |
81 | break; | |
82 | } | |
83 | DMINFO("Reconnected to userspace log server... DM_ULOG_CTR complete"); | |
84 | r = dm_consult_userspace(uuid, DM_ULOG_RESUME, NULL, | |
85 | 0, NULL, NULL); | |
86 | if (!r) | |
87 | goto retry; | |
88 | ||
89 | DMERR("Error trying to resume userspace log: %d", r); | |
90 | ||
91 | return -ESRCH; | |
92 | } | |
93 | ||
94 | static int build_constructor_string(struct dm_target *ti, | |
95 | unsigned argc, char **argv, | |
96 | char **ctr_str) | |
97 | { | |
98 | int i, str_size; | |
99 | char *str = NULL; | |
100 | ||
101 | *ctr_str = NULL; | |
102 | ||
103 | for (i = 0, str_size = 0; i < argc; i++) | |
104 | str_size += strlen(argv[i]) + 1; /* +1 for space between args */ | |
105 | ||
106 | str_size += 20; /* Max number of chars in a printed u64 number */ | |
107 | ||
108 | str = kzalloc(str_size, GFP_KERNEL); | |
109 | if (!str) { | |
110 | DMWARN("Unable to allocate memory for constructor string"); | |
111 | return -ENOMEM; | |
112 | } | |
113 | ||
114 | for (i = 0, str_size = 0; i < argc; i++) | |
115 | str_size += sprintf(str + str_size, "%s ", argv[i]); | |
116 | str_size += sprintf(str + str_size, "%llu", | |
117 | (unsigned long long)ti->len); | |
118 | ||
119 | *ctr_str = str; | |
120 | return str_size; | |
121 | } | |
122 | ||
123 | /* | |
124 | * userspace_ctr | |
125 | * | |
126 | * argv contains: | |
127 | * <UUID> <other args> | |
128 | * Where 'other args' is the userspace implementation specific log | |
129 | * arguments. An example might be: | |
130 | * <UUID> clustered_disk <arg count> <log dev> <region_size> [[no]sync] | |
131 | * | |
132 | * So, this module will strip off the <UUID> for identification purposes | |
133 | * when communicating with userspace about a log; but will pass on everything | |
134 | * else. | |
135 | */ | |
136 | static int userspace_ctr(struct dm_dirty_log *log, struct dm_target *ti, | |
137 | unsigned argc, char **argv) | |
138 | { | |
139 | int r = 0; | |
140 | int str_size; | |
141 | char *ctr_str = NULL; | |
142 | struct log_c *lc = NULL; | |
143 | uint64_t rdata; | |
144 | size_t rdata_size = sizeof(rdata); | |
145 | ||
146 | if (argc < 3) { | |
147 | DMWARN("Too few arguments to userspace dirty log"); | |
148 | return -EINVAL; | |
149 | } | |
150 | ||
151 | lc = kmalloc(sizeof(*lc), GFP_KERNEL); | |
152 | if (!lc) { | |
153 | DMWARN("Unable to allocate userspace log context."); | |
154 | return -ENOMEM; | |
155 | } | |
156 | ||
157 | lc->ti = ti; | |
158 | ||
159 | if (strlen(argv[0]) > (DM_UUID_LEN - 1)) { | |
160 | DMWARN("UUID argument too long."); | |
161 | kfree(lc); | |
162 | return -EINVAL; | |
163 | } | |
164 | ||
165 | strncpy(lc->uuid, argv[0], DM_UUID_LEN); | |
166 | spin_lock_init(&lc->flush_lock); | |
167 | INIT_LIST_HEAD(&lc->flush_list); | |
168 | ||
169 | str_size = build_constructor_string(ti, argc - 1, argv + 1, &ctr_str); | |
170 | if (str_size < 0) { | |
171 | kfree(lc); | |
172 | return str_size; | |
173 | } | |
174 | ||
175 | /* Send table string */ | |
176 | r = dm_consult_userspace(lc->uuid, DM_ULOG_CTR, | |
177 | ctr_str, str_size, NULL, NULL); | |
178 | ||
179 | if (r == -ESRCH) { | |
180 | DMERR("Userspace log server not found"); | |
181 | goto out; | |
182 | } | |
183 | ||
184 | /* Since the region size does not change, get it now */ | |
185 | rdata_size = sizeof(rdata); | |
186 | r = dm_consult_userspace(lc->uuid, DM_ULOG_GET_REGION_SIZE, | |
187 | NULL, 0, (char *)&rdata, &rdata_size); | |
188 | ||
189 | if (r) { | |
190 | DMERR("Failed to get region size of dirty log"); | |
191 | goto out; | |
192 | } | |
193 | ||
194 | lc->region_size = (uint32_t)rdata; | |
195 | lc->region_count = dm_sector_div_up(ti->len, lc->region_size); | |
196 | ||
197 | out: | |
198 | if (r) { | |
199 | kfree(lc); | |
200 | kfree(ctr_str); | |
201 | } else { | |
202 | lc->usr_argv_str = ctr_str; | |
203 | lc->usr_argc = argc; | |
204 | log->context = lc; | |
205 | } | |
206 | ||
207 | return r; | |
208 | } | |
209 | ||
210 | static void userspace_dtr(struct dm_dirty_log *log) | |
211 | { | |
212 | int r; | |
213 | struct log_c *lc = log->context; | |
214 | ||
215 | r = dm_consult_userspace(lc->uuid, DM_ULOG_DTR, | |
216 | NULL, 0, | |
217 | NULL, NULL); | |
218 | ||
219 | kfree(lc->usr_argv_str); | |
220 | kfree(lc); | |
221 | ||
222 | return; | |
223 | } | |
224 | ||
225 | static int userspace_presuspend(struct dm_dirty_log *log) | |
226 | { | |
227 | int r; | |
228 | struct log_c *lc = log->context; | |
229 | ||
230 | r = dm_consult_userspace(lc->uuid, DM_ULOG_PRESUSPEND, | |
231 | NULL, 0, | |
232 | NULL, NULL); | |
233 | ||
234 | return r; | |
235 | } | |
236 | ||
237 | static int userspace_postsuspend(struct dm_dirty_log *log) | |
238 | { | |
239 | int r; | |
240 | struct log_c *lc = log->context; | |
241 | ||
242 | r = dm_consult_userspace(lc->uuid, DM_ULOG_POSTSUSPEND, | |
243 | NULL, 0, | |
244 | NULL, NULL); | |
245 | ||
246 | return r; | |
247 | } | |
248 | ||
249 | static int userspace_resume(struct dm_dirty_log *log) | |
250 | { | |
251 | int r; | |
252 | struct log_c *lc = log->context; | |
253 | ||
254 | lc->in_sync_hint = 0; | |
255 | r = dm_consult_userspace(lc->uuid, DM_ULOG_RESUME, | |
256 | NULL, 0, | |
257 | NULL, NULL); | |
258 | ||
259 | return r; | |
260 | } | |
261 | ||
262 | static uint32_t userspace_get_region_size(struct dm_dirty_log *log) | |
263 | { | |
264 | struct log_c *lc = log->context; | |
265 | ||
266 | return lc->region_size; | |
267 | } | |
268 | ||
269 | /* | |
270 | * userspace_is_clean | |
271 | * | |
272 | * Check whether a region is clean. If there is any sort of | |
273 | * failure when consulting the server, we return not clean. | |
274 | * | |
275 | * Returns: 1 if clean, 0 otherwise | |
276 | */ | |
277 | static int userspace_is_clean(struct dm_dirty_log *log, region_t region) | |
278 | { | |
279 | int r; | |
280 | uint64_t region64 = (uint64_t)region; | |
281 | int64_t is_clean; | |
282 | size_t rdata_size; | |
283 | struct log_c *lc = log->context; | |
284 | ||
285 | rdata_size = sizeof(is_clean); | |
286 | r = userspace_do_request(lc, lc->uuid, DM_ULOG_IS_CLEAN, | |
287 | (char *)®ion64, sizeof(region64), | |
288 | (char *)&is_clean, &rdata_size); | |
289 | ||
290 | return (r) ? 0 : (int)is_clean; | |
291 | } | |
292 | ||
293 | /* | |
294 | * userspace_in_sync | |
295 | * | |
296 | * Check if the region is in-sync. If there is any sort | |
297 | * of failure when consulting the server, we assume that | |
298 | * the region is not in sync. | |
299 | * | |
300 | * If 'can_block' is set, return immediately | |
301 | * | |
302 | * Returns: 1 if in-sync, 0 if not-in-sync, -EWOULDBLOCK | |
303 | */ | |
304 | static int userspace_in_sync(struct dm_dirty_log *log, region_t region, | |
305 | int can_block) | |
306 | { | |
307 | int r; | |
308 | uint64_t region64 = region; | |
309 | int64_t in_sync; | |
310 | size_t rdata_size; | |
311 | struct log_c *lc = log->context; | |
312 | ||
313 | /* | |
314 | * We can never respond directly - even if in_sync_hint is | |
315 | * set. This is because another machine could see a device | |
316 | * failure and mark the region out-of-sync. If we don't go | |
317 | * to userspace to ask, we might think the region is in-sync | |
318 | * and allow a read to pick up data that is stale. (This is | |
319 | * very unlikely if a device actually fails; but it is very | |
320 | * likely if a connection to one device from one machine fails.) | |
321 | * | |
322 | * There still might be a problem if the mirror caches the region | |
323 | * state as in-sync... but then this call would not be made. So, | |
324 | * that is a mirror problem. | |
325 | */ | |
326 | if (!can_block) | |
327 | return -EWOULDBLOCK; | |
328 | ||
329 | rdata_size = sizeof(in_sync); | |
330 | r = userspace_do_request(lc, lc->uuid, DM_ULOG_IN_SYNC, | |
331 | (char *)®ion64, sizeof(region64), | |
332 | (char *)&in_sync, &rdata_size); | |
333 | return (r) ? 0 : (int)in_sync; | |
334 | } | |
335 | ||
336 | /* | |
337 | * userspace_flush | |
338 | * | |
339 | * This function is ok to block. | |
340 | * The flush happens in two stages. First, it sends all | |
341 | * clear/mark requests that are on the list. Then it | |
342 | * tells the server to commit them. This gives the | |
343 | * server a chance to optimise the commit, instead of | |
344 | * doing it for every request. | |
345 | * | |
346 | * Additionally, we could implement another thread that | |
347 | * sends the requests up to the server - reducing the | |
348 | * load on flush. Then the flush would have less in | |
349 | * the list and be responsible for the finishing commit. | |
350 | * | |
351 | * Returns: 0 on success, < 0 on failure | |
352 | */ | |
353 | static int userspace_flush(struct dm_dirty_log *log) | |
354 | { | |
355 | int r = 0; | |
356 | unsigned long flags; | |
357 | struct log_c *lc = log->context; | |
358 | LIST_HEAD(flush_list); | |
359 | struct flush_entry *fe, *tmp_fe; | |
360 | ||
361 | spin_lock_irqsave(&lc->flush_lock, flags); | |
362 | list_splice_init(&lc->flush_list, &flush_list); | |
363 | spin_unlock_irqrestore(&lc->flush_lock, flags); | |
364 | ||
365 | if (list_empty(&flush_list)) | |
366 | return 0; | |
367 | ||
368 | /* | |
369 | * FIXME: Count up requests, group request types, | |
370 | * allocate memory to stick all requests in and | |
371 | * send to server in one go. Failing the allocation, | |
372 | * do it one by one. | |
373 | */ | |
374 | ||
375 | list_for_each_entry(fe, &flush_list, list) { | |
376 | r = userspace_do_request(lc, lc->uuid, fe->type, | |
377 | (char *)&fe->region, | |
378 | sizeof(fe->region), | |
379 | NULL, NULL); | |
380 | if (r) | |
381 | goto fail; | |
382 | } | |
383 | ||
384 | r = userspace_do_request(lc, lc->uuid, DM_ULOG_FLUSH, | |
385 | NULL, 0, NULL, NULL); | |
386 | ||
387 | fail: | |
388 | /* | |
389 | * We can safely remove these entries, even if failure. | |
390 | * Calling code will receive an error and will know that | |
391 | * the log facility has failed. | |
392 | */ | |
393 | list_for_each_entry_safe(fe, tmp_fe, &flush_list, list) { | |
394 | list_del(&fe->list); | |
395 | mempool_free(fe, flush_entry_pool); | |
396 | } | |
397 | ||
398 | if (r) | |
399 | dm_table_event(lc->ti->table); | |
400 | ||
401 | return r; | |
402 | } | |
403 | ||
404 | /* | |
405 | * userspace_mark_region | |
406 | * | |
407 | * This function should avoid blocking unless absolutely required. | |
408 | * (Memory allocation is valid for blocking.) | |
409 | */ | |
410 | static void userspace_mark_region(struct dm_dirty_log *log, region_t region) | |
411 | { | |
412 | unsigned long flags; | |
413 | struct log_c *lc = log->context; | |
414 | struct flush_entry *fe; | |
415 | ||
416 | /* Wait for an allocation, but _never_ fail */ | |
417 | fe = mempool_alloc(flush_entry_pool, GFP_NOIO); | |
418 | BUG_ON(!fe); | |
419 | ||
420 | spin_lock_irqsave(&lc->flush_lock, flags); | |
421 | fe->type = DM_ULOG_MARK_REGION; | |
422 | fe->region = region; | |
423 | list_add(&fe->list, &lc->flush_list); | |
424 | spin_unlock_irqrestore(&lc->flush_lock, flags); | |
425 | ||
426 | return; | |
427 | } | |
428 | ||
429 | /* | |
430 | * userspace_clear_region | |
431 | * | |
432 | * This function must not block. | |
433 | * So, the alloc can't block. In the worst case, it is ok to | |
434 | * fail. It would simply mean we can't clear the region. | |
435 | * Does nothing to current sync context, but does mean | |
436 | * the region will be re-sync'ed on a reload of the mirror | |
437 | * even though it is in-sync. | |
438 | */ | |
439 | static void userspace_clear_region(struct dm_dirty_log *log, region_t region) | |
440 | { | |
441 | unsigned long flags; | |
442 | struct log_c *lc = log->context; | |
443 | struct flush_entry *fe; | |
444 | ||
445 | /* | |
446 | * If we fail to allocate, we skip the clearing of | |
447 | * the region. This doesn't hurt us in any way, except | |
448 | * to cause the region to be resync'ed when the | |
449 | * device is activated next time. | |
450 | */ | |
451 | fe = mempool_alloc(flush_entry_pool, GFP_ATOMIC); | |
452 | if (!fe) { | |
453 | DMERR("Failed to allocate memory to clear region."); | |
454 | return; | |
455 | } | |
456 | ||
457 | spin_lock_irqsave(&lc->flush_lock, flags); | |
458 | fe->type = DM_ULOG_CLEAR_REGION; | |
459 | fe->region = region; | |
460 | list_add(&fe->list, &lc->flush_list); | |
461 | spin_unlock_irqrestore(&lc->flush_lock, flags); | |
462 | ||
463 | return; | |
464 | } | |
465 | ||
466 | /* | |
467 | * userspace_get_resync_work | |
468 | * | |
469 | * Get a region that needs recovery. It is valid to return | |
470 | * an error for this function. | |
471 | * | |
472 | * Returns: 1 if region filled, 0 if no work, <0 on error | |
473 | */ | |
474 | static int userspace_get_resync_work(struct dm_dirty_log *log, region_t *region) | |
475 | { | |
476 | int r; | |
477 | size_t rdata_size; | |
478 | struct log_c *lc = log->context; | |
479 | struct { | |
480 | int64_t i; /* 64-bit for mix arch compatibility */ | |
481 | region_t r; | |
482 | } pkg; | |
483 | ||
484 | if (lc->in_sync_hint >= lc->region_count) | |
485 | return 0; | |
486 | ||
487 | rdata_size = sizeof(pkg); | |
488 | r = userspace_do_request(lc, lc->uuid, DM_ULOG_GET_RESYNC_WORK, | |
489 | NULL, 0, | |
490 | (char *)&pkg, &rdata_size); | |
491 | ||
492 | *region = pkg.r; | |
493 | return (r) ? r : (int)pkg.i; | |
494 | } | |
495 | ||
496 | /* | |
497 | * userspace_set_region_sync | |
498 | * | |
499 | * Set the sync status of a given region. This function | |
500 | * must not fail. | |
501 | */ | |
502 | static void userspace_set_region_sync(struct dm_dirty_log *log, | |
503 | region_t region, int in_sync) | |
504 | { | |
505 | int r; | |
506 | struct log_c *lc = log->context; | |
507 | struct { | |
508 | region_t r; | |
509 | int64_t i; | |
510 | } pkg; | |
511 | ||
512 | pkg.r = region; | |
513 | pkg.i = (int64_t)in_sync; | |
514 | ||
515 | r = userspace_do_request(lc, lc->uuid, DM_ULOG_SET_REGION_SYNC, | |
516 | (char *)&pkg, sizeof(pkg), | |
517 | NULL, NULL); | |
518 | ||
519 | /* | |
520 | * It would be nice to be able to report failures. | |
521 | * However, it is easy emough to detect and resolve. | |
522 | */ | |
523 | return; | |
524 | } | |
525 | ||
526 | /* | |
527 | * userspace_get_sync_count | |
528 | * | |
529 | * If there is any sort of failure when consulting the server, | |
530 | * we assume that the sync count is zero. | |
531 | * | |
532 | * Returns: sync count on success, 0 on failure | |
533 | */ | |
534 | static region_t userspace_get_sync_count(struct dm_dirty_log *log) | |
535 | { | |
536 | int r; | |
537 | size_t rdata_size; | |
538 | uint64_t sync_count; | |
539 | struct log_c *lc = log->context; | |
540 | ||
541 | rdata_size = sizeof(sync_count); | |
542 | r = userspace_do_request(lc, lc->uuid, DM_ULOG_GET_SYNC_COUNT, | |
543 | NULL, 0, | |
544 | (char *)&sync_count, &rdata_size); | |
545 | ||
546 | if (r) | |
547 | return 0; | |
548 | ||
549 | if (sync_count >= lc->region_count) | |
550 | lc->in_sync_hint = lc->region_count; | |
551 | ||
552 | return (region_t)sync_count; | |
553 | } | |
554 | ||
555 | /* | |
556 | * userspace_status | |
557 | * | |
558 | * Returns: amount of space consumed | |
559 | */ | |
560 | static int userspace_status(struct dm_dirty_log *log, status_type_t status_type, | |
561 | char *result, unsigned maxlen) | |
562 | { | |
563 | int r = 0; | |
564 | size_t sz = (size_t)maxlen; | |
565 | struct log_c *lc = log->context; | |
566 | ||
567 | switch (status_type) { | |
568 | case STATUSTYPE_INFO: | |
569 | r = userspace_do_request(lc, lc->uuid, DM_ULOG_STATUS_INFO, | |
570 | NULL, 0, | |
571 | result, &sz); | |
572 | ||
573 | if (r) { | |
574 | sz = 0; | |
575 | DMEMIT("%s 1 COM_FAILURE", log->type->name); | |
576 | } | |
577 | break; | |
578 | case STATUSTYPE_TABLE: | |
579 | sz = 0; | |
4142a969 | 580 | DMEMIT("%s %u %s %s ", log->type->name, lc->usr_argc + 1, |
f5db4af4 JB |
581 | lc->uuid, lc->usr_argv_str); |
582 | break; | |
583 | } | |
584 | return (r) ? 0 : (int)sz; | |
585 | } | |
586 | ||
587 | /* | |
588 | * userspace_is_remote_recovering | |
589 | * | |
590 | * Returns: 1 if region recovering, 0 otherwise | |
591 | */ | |
592 | static int userspace_is_remote_recovering(struct dm_dirty_log *log, | |
593 | region_t region) | |
594 | { | |
595 | int r; | |
596 | uint64_t region64 = region; | |
597 | struct log_c *lc = log->context; | |
598 | static unsigned long long limit; | |
599 | struct { | |
600 | int64_t is_recovering; | |
601 | uint64_t in_sync_hint; | |
602 | } pkg; | |
603 | size_t rdata_size = sizeof(pkg); | |
604 | ||
605 | /* | |
606 | * Once the mirror has been reported to be in-sync, | |
607 | * it will never again ask for recovery work. So, | |
608 | * we can safely say there is not a remote machine | |
609 | * recovering if the device is in-sync. (in_sync_hint | |
610 | * must be reset at resume time.) | |
611 | */ | |
612 | if (region < lc->in_sync_hint) | |
613 | return 0; | |
614 | else if (jiffies < limit) | |
615 | return 1; | |
616 | ||
617 | limit = jiffies + (HZ / 4); | |
618 | r = userspace_do_request(lc, lc->uuid, DM_ULOG_IS_REMOTE_RECOVERING, | |
619 | (char *)®ion64, sizeof(region64), | |
620 | (char *)&pkg, &rdata_size); | |
621 | if (r) | |
622 | return 1; | |
623 | ||
624 | lc->in_sync_hint = pkg.in_sync_hint; | |
625 | ||
626 | return (int)pkg.is_recovering; | |
627 | } | |
628 | ||
629 | static struct dm_dirty_log_type _userspace_type = { | |
630 | .name = "userspace", | |
631 | .module = THIS_MODULE, | |
632 | .ctr = userspace_ctr, | |
633 | .dtr = userspace_dtr, | |
634 | .presuspend = userspace_presuspend, | |
635 | .postsuspend = userspace_postsuspend, | |
636 | .resume = userspace_resume, | |
637 | .get_region_size = userspace_get_region_size, | |
638 | .is_clean = userspace_is_clean, | |
639 | .in_sync = userspace_in_sync, | |
640 | .flush = userspace_flush, | |
641 | .mark_region = userspace_mark_region, | |
642 | .clear_region = userspace_clear_region, | |
643 | .get_resync_work = userspace_get_resync_work, | |
644 | .set_region_sync = userspace_set_region_sync, | |
645 | .get_sync_count = userspace_get_sync_count, | |
646 | .status = userspace_status, | |
647 | .is_remote_recovering = userspace_is_remote_recovering, | |
648 | }; | |
649 | ||
650 | static int __init userspace_dirty_log_init(void) | |
651 | { | |
652 | int r = 0; | |
653 | ||
654 | flush_entry_pool = mempool_create(100, flush_entry_alloc, | |
655 | flush_entry_free, NULL); | |
656 | ||
657 | if (!flush_entry_pool) { | |
658 | DMWARN("Unable to create flush_entry_pool: No memory."); | |
659 | return -ENOMEM; | |
660 | } | |
661 | ||
662 | r = dm_ulog_tfr_init(); | |
663 | if (r) { | |
664 | DMWARN("Unable to initialize userspace log communications"); | |
665 | mempool_destroy(flush_entry_pool); | |
666 | return r; | |
667 | } | |
668 | ||
669 | r = dm_dirty_log_type_register(&_userspace_type); | |
670 | if (r) { | |
671 | DMWARN("Couldn't register userspace dirty log type"); | |
672 | dm_ulog_tfr_exit(); | |
673 | mempool_destroy(flush_entry_pool); | |
674 | return r; | |
675 | } | |
676 | ||
677 | DMINFO("version 1.0.0 loaded"); | |
678 | return 0; | |
679 | } | |
680 | ||
681 | static void __exit userspace_dirty_log_exit(void) | |
682 | { | |
683 | dm_dirty_log_type_unregister(&_userspace_type); | |
684 | dm_ulog_tfr_exit(); | |
685 | mempool_destroy(flush_entry_pool); | |
686 | ||
687 | DMINFO("version 1.0.0 unloaded"); | |
688 | return; | |
689 | } | |
690 | ||
691 | module_init(userspace_dirty_log_init); | |
692 | module_exit(userspace_dirty_log_exit); | |
693 | ||
694 | MODULE_DESCRIPTION(DM_NAME " userspace dirty log link"); | |
695 | MODULE_AUTHOR("Jonathan Brassow <dm-devel@redhat.com>"); | |
696 | MODULE_LICENSE("GPL"); |