Commit | Line | Data |
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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> | |
5a0e3ad6 | 8 | #include <linux/slab.h> |
f5db4af4 JB |
9 | #include <linux/dm-dirty-log.h> |
10 | #include <linux/device-mapper.h> | |
11 | #include <linux/dm-log-userspace.h> | |
12 | ||
13 | #include "dm-log-userspace-transfer.h" | |
14 | ||
15 | struct flush_entry { | |
16 | int type; | |
17 | region_t region; | |
18 | struct list_head list; | |
19 | }; | |
20 | ||
21 | struct log_c { | |
22 | struct dm_target *ti; | |
23 | uint32_t region_size; | |
24 | region_t region_count; | |
7ec23d50 | 25 | uint64_t luid; |
f5db4af4 JB |
26 | char uuid[DM_UUID_LEN]; |
27 | ||
28 | char *usr_argv_str; | |
29 | uint32_t usr_argc; | |
30 | ||
31 | /* | |
32 | * in_sync_hint gets set when doing is_remote_recovering. It | |
33 | * represents the first region that needs recovery. IOW, the | |
34 | * first zero bit of sync_bits. This can be useful for to limit | |
35 | * traffic for calls like is_remote_recovering and get_resync_work, | |
36 | * but be take care in its use for anything else. | |
37 | */ | |
38 | uint64_t in_sync_hint; | |
39 | ||
909cc4fb JB |
40 | /* |
41 | * Mark and clear requests are held until a flush is issued | |
42 | * so that we can group, and thereby limit, the amount of | |
43 | * network traffic between kernel and userspace. The 'flush_lock' | |
44 | * is used to protect these lists. | |
45 | */ | |
f5db4af4 | 46 | spinlock_t flush_lock; |
909cc4fb JB |
47 | struct list_head mark_list; |
48 | struct list_head clear_list; | |
f5db4af4 JB |
49 | }; |
50 | ||
51 | static mempool_t *flush_entry_pool; | |
52 | ||
53 | static void *flush_entry_alloc(gfp_t gfp_mask, void *pool_data) | |
54 | { | |
55 | return kmalloc(sizeof(struct flush_entry), gfp_mask); | |
56 | } | |
57 | ||
58 | static void flush_entry_free(void *element, void *pool_data) | |
59 | { | |
60 | kfree(element); | |
61 | } | |
62 | ||
63 | static int userspace_do_request(struct log_c *lc, const char *uuid, | |
64 | int request_type, char *data, size_t data_size, | |
65 | char *rdata, size_t *rdata_size) | |
66 | { | |
67 | int r; | |
68 | ||
69 | /* | |
70 | * If the server isn't there, -ESRCH is returned, | |
71 | * and we must keep trying until the server is | |
72 | * restored. | |
73 | */ | |
74 | retry: | |
7ec23d50 | 75 | r = dm_consult_userspace(uuid, lc->luid, request_type, data, |
f5db4af4 JB |
76 | data_size, rdata, rdata_size); |
77 | ||
78 | if (r != -ESRCH) | |
79 | return r; | |
80 | ||
81 | DMERR(" Userspace log server not found."); | |
82 | while (1) { | |
83 | set_current_state(TASK_INTERRUPTIBLE); | |
84 | schedule_timeout(2*HZ); | |
85 | DMWARN("Attempting to contact userspace log server..."); | |
7ec23d50 JB |
86 | r = dm_consult_userspace(uuid, lc->luid, DM_ULOG_CTR, |
87 | lc->usr_argv_str, | |
f5db4af4 JB |
88 | strlen(lc->usr_argv_str) + 1, |
89 | NULL, NULL); | |
90 | if (!r) | |
91 | break; | |
92 | } | |
93 | DMINFO("Reconnected to userspace log server... DM_ULOG_CTR complete"); | |
7ec23d50 | 94 | r = dm_consult_userspace(uuid, lc->luid, DM_ULOG_RESUME, NULL, |
f5db4af4 JB |
95 | 0, NULL, NULL); |
96 | if (!r) | |
97 | goto retry; | |
98 | ||
99 | DMERR("Error trying to resume userspace log: %d", r); | |
100 | ||
101 | return -ESRCH; | |
102 | } | |
103 | ||
104 | static int build_constructor_string(struct dm_target *ti, | |
105 | unsigned argc, char **argv, | |
106 | char **ctr_str) | |
107 | { | |
108 | int i, str_size; | |
109 | char *str = NULL; | |
110 | ||
111 | *ctr_str = NULL; | |
112 | ||
113 | for (i = 0, str_size = 0; i < argc; i++) | |
114 | str_size += strlen(argv[i]) + 1; /* +1 for space between args */ | |
115 | ||
116 | str_size += 20; /* Max number of chars in a printed u64 number */ | |
117 | ||
118 | str = kzalloc(str_size, GFP_KERNEL); | |
119 | if (!str) { | |
120 | DMWARN("Unable to allocate memory for constructor string"); | |
121 | return -ENOMEM; | |
122 | } | |
123 | ||
b8313b6d JB |
124 | str_size = sprintf(str, "%llu", (unsigned long long)ti->len); |
125 | for (i = 0; i < argc; i++) | |
126 | str_size += sprintf(str + str_size, " %s", argv[i]); | |
f5db4af4 JB |
127 | |
128 | *ctr_str = str; | |
129 | return str_size; | |
130 | } | |
131 | ||
132 | /* | |
133 | * userspace_ctr | |
134 | * | |
135 | * argv contains: | |
136 | * <UUID> <other args> | |
137 | * Where 'other args' is the userspace implementation specific log | |
138 | * arguments. An example might be: | |
139 | * <UUID> clustered_disk <arg count> <log dev> <region_size> [[no]sync] | |
140 | * | |
141 | * So, this module will strip off the <UUID> for identification purposes | |
142 | * when communicating with userspace about a log; but will pass on everything | |
143 | * else. | |
144 | */ | |
145 | static int userspace_ctr(struct dm_dirty_log *log, struct dm_target *ti, | |
146 | unsigned argc, char **argv) | |
147 | { | |
148 | int r = 0; | |
149 | int str_size; | |
150 | char *ctr_str = NULL; | |
151 | struct log_c *lc = NULL; | |
152 | uint64_t rdata; | |
153 | size_t rdata_size = sizeof(rdata); | |
154 | ||
155 | if (argc < 3) { | |
156 | DMWARN("Too few arguments to userspace dirty log"); | |
157 | return -EINVAL; | |
158 | } | |
159 | ||
160 | lc = kmalloc(sizeof(*lc), GFP_KERNEL); | |
161 | if (!lc) { | |
162 | DMWARN("Unable to allocate userspace log context."); | |
163 | return -ENOMEM; | |
164 | } | |
165 | ||
7ec23d50 | 166 | /* The ptr value is sufficient for local unique id */ |
bca915aa | 167 | lc->luid = (unsigned long)lc; |
7ec23d50 | 168 | |
f5db4af4 JB |
169 | lc->ti = ti; |
170 | ||
171 | if (strlen(argv[0]) > (DM_UUID_LEN - 1)) { | |
172 | DMWARN("UUID argument too long."); | |
173 | kfree(lc); | |
174 | return -EINVAL; | |
175 | } | |
176 | ||
177 | strncpy(lc->uuid, argv[0], DM_UUID_LEN); | |
178 | spin_lock_init(&lc->flush_lock); | |
909cc4fb JB |
179 | INIT_LIST_HEAD(&lc->mark_list); |
180 | INIT_LIST_HEAD(&lc->clear_list); | |
f5db4af4 JB |
181 | |
182 | str_size = build_constructor_string(ti, argc - 1, argv + 1, &ctr_str); | |
183 | if (str_size < 0) { | |
184 | kfree(lc); | |
185 | return str_size; | |
186 | } | |
187 | ||
188 | /* Send table string */ | |
7ec23d50 | 189 | r = dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_CTR, |
f5db4af4 JB |
190 | ctr_str, str_size, NULL, NULL); |
191 | ||
4a038677 JB |
192 | if (r < 0) { |
193 | if (r == -ESRCH) | |
194 | DMERR("Userspace log server not found"); | |
195 | else | |
196 | DMERR("Userspace log server failed to create log"); | |
f5db4af4 JB |
197 | goto out; |
198 | } | |
199 | ||
200 | /* Since the region size does not change, get it now */ | |
201 | rdata_size = sizeof(rdata); | |
7ec23d50 | 202 | r = dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_GET_REGION_SIZE, |
f5db4af4 JB |
203 | NULL, 0, (char *)&rdata, &rdata_size); |
204 | ||
205 | if (r) { | |
206 | DMERR("Failed to get region size of dirty log"); | |
207 | goto out; | |
208 | } | |
209 | ||
210 | lc->region_size = (uint32_t)rdata; | |
211 | lc->region_count = dm_sector_div_up(ti->len, lc->region_size); | |
212 | ||
213 | out: | |
214 | if (r) { | |
215 | kfree(lc); | |
216 | kfree(ctr_str); | |
217 | } else { | |
218 | lc->usr_argv_str = ctr_str; | |
219 | lc->usr_argc = argc; | |
220 | log->context = lc; | |
221 | } | |
222 | ||
223 | return r; | |
224 | } | |
225 | ||
226 | static void userspace_dtr(struct dm_dirty_log *log) | |
227 | { | |
f5db4af4 JB |
228 | struct log_c *lc = log->context; |
229 | ||
4a038677 | 230 | (void) dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_DTR, |
f5db4af4 JB |
231 | NULL, 0, |
232 | NULL, NULL); | |
233 | ||
234 | kfree(lc->usr_argv_str); | |
235 | kfree(lc); | |
236 | ||
237 | return; | |
238 | } | |
239 | ||
240 | static int userspace_presuspend(struct dm_dirty_log *log) | |
241 | { | |
242 | int r; | |
243 | struct log_c *lc = log->context; | |
244 | ||
7ec23d50 | 245 | r = dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_PRESUSPEND, |
f5db4af4 JB |
246 | NULL, 0, |
247 | NULL, NULL); | |
248 | ||
249 | return r; | |
250 | } | |
251 | ||
252 | static int userspace_postsuspend(struct dm_dirty_log *log) | |
253 | { | |
254 | int r; | |
255 | struct log_c *lc = log->context; | |
256 | ||
7ec23d50 | 257 | r = dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_POSTSUSPEND, |
f5db4af4 JB |
258 | NULL, 0, |
259 | NULL, NULL); | |
260 | ||
261 | return r; | |
262 | } | |
263 | ||
264 | static int userspace_resume(struct dm_dirty_log *log) | |
265 | { | |
266 | int r; | |
267 | struct log_c *lc = log->context; | |
268 | ||
269 | lc->in_sync_hint = 0; | |
7ec23d50 | 270 | r = dm_consult_userspace(lc->uuid, lc->luid, DM_ULOG_RESUME, |
f5db4af4 JB |
271 | NULL, 0, |
272 | NULL, NULL); | |
273 | ||
274 | return r; | |
275 | } | |
276 | ||
277 | static uint32_t userspace_get_region_size(struct dm_dirty_log *log) | |
278 | { | |
279 | struct log_c *lc = log->context; | |
280 | ||
281 | return lc->region_size; | |
282 | } | |
283 | ||
284 | /* | |
285 | * userspace_is_clean | |
286 | * | |
287 | * Check whether a region is clean. If there is any sort of | |
288 | * failure when consulting the server, we return not clean. | |
289 | * | |
290 | * Returns: 1 if clean, 0 otherwise | |
291 | */ | |
292 | static int userspace_is_clean(struct dm_dirty_log *log, region_t region) | |
293 | { | |
294 | int r; | |
295 | uint64_t region64 = (uint64_t)region; | |
296 | int64_t is_clean; | |
297 | size_t rdata_size; | |
298 | struct log_c *lc = log->context; | |
299 | ||
300 | rdata_size = sizeof(is_clean); | |
301 | r = userspace_do_request(lc, lc->uuid, DM_ULOG_IS_CLEAN, | |
302 | (char *)®ion64, sizeof(region64), | |
303 | (char *)&is_clean, &rdata_size); | |
304 | ||
305 | return (r) ? 0 : (int)is_clean; | |
306 | } | |
307 | ||
308 | /* | |
309 | * userspace_in_sync | |
310 | * | |
311 | * Check if the region is in-sync. If there is any sort | |
312 | * of failure when consulting the server, we assume that | |
313 | * the region is not in sync. | |
314 | * | |
315 | * If 'can_block' is set, return immediately | |
316 | * | |
317 | * Returns: 1 if in-sync, 0 if not-in-sync, -EWOULDBLOCK | |
318 | */ | |
319 | static int userspace_in_sync(struct dm_dirty_log *log, region_t region, | |
320 | int can_block) | |
321 | { | |
322 | int r; | |
323 | uint64_t region64 = region; | |
324 | int64_t in_sync; | |
325 | size_t rdata_size; | |
326 | struct log_c *lc = log->context; | |
327 | ||
328 | /* | |
329 | * We can never respond directly - even if in_sync_hint is | |
330 | * set. This is because another machine could see a device | |
331 | * failure and mark the region out-of-sync. If we don't go | |
332 | * to userspace to ask, we might think the region is in-sync | |
333 | * and allow a read to pick up data that is stale. (This is | |
334 | * very unlikely if a device actually fails; but it is very | |
335 | * likely if a connection to one device from one machine fails.) | |
336 | * | |
337 | * There still might be a problem if the mirror caches the region | |
338 | * state as in-sync... but then this call would not be made. So, | |
339 | * that is a mirror problem. | |
340 | */ | |
341 | if (!can_block) | |
342 | return -EWOULDBLOCK; | |
343 | ||
344 | rdata_size = sizeof(in_sync); | |
345 | r = userspace_do_request(lc, lc->uuid, DM_ULOG_IN_SYNC, | |
346 | (char *)®ion64, sizeof(region64), | |
347 | (char *)&in_sync, &rdata_size); | |
348 | return (r) ? 0 : (int)in_sync; | |
349 | } | |
350 | ||
351 | /* | |
352 | * userspace_flush | |
353 | * | |
354 | * This function is ok to block. | |
355 | * The flush happens in two stages. First, it sends all | |
356 | * clear/mark requests that are on the list. Then it | |
357 | * tells the server to commit them. This gives the | |
358 | * server a chance to optimise the commit, instead of | |
359 | * doing it for every request. | |
360 | * | |
361 | * Additionally, we could implement another thread that | |
362 | * sends the requests up to the server - reducing the | |
363 | * load on flush. Then the flush would have less in | |
364 | * the list and be responsible for the finishing commit. | |
365 | * | |
366 | * Returns: 0 on success, < 0 on failure | |
367 | */ | |
368 | static int userspace_flush(struct dm_dirty_log *log) | |
369 | { | |
370 | int r = 0; | |
371 | unsigned long flags; | |
372 | struct log_c *lc = log->context; | |
909cc4fb JB |
373 | LIST_HEAD(mark_list); |
374 | LIST_HEAD(clear_list); | |
f5db4af4 JB |
375 | struct flush_entry *fe, *tmp_fe; |
376 | ||
377 | spin_lock_irqsave(&lc->flush_lock, flags); | |
909cc4fb JB |
378 | list_splice_init(&lc->mark_list, &mark_list); |
379 | list_splice_init(&lc->clear_list, &clear_list); | |
f5db4af4 JB |
380 | spin_unlock_irqrestore(&lc->flush_lock, flags); |
381 | ||
909cc4fb | 382 | if (list_empty(&mark_list) && list_empty(&clear_list)) |
f5db4af4 JB |
383 | return 0; |
384 | ||
385 | /* | |
386 | * FIXME: Count up requests, group request types, | |
387 | * allocate memory to stick all requests in and | |
388 | * send to server in one go. Failing the allocation, | |
389 | * do it one by one. | |
390 | */ | |
391 | ||
909cc4fb JB |
392 | list_for_each_entry(fe, &mark_list, list) { |
393 | r = userspace_do_request(lc, lc->uuid, fe->type, | |
394 | (char *)&fe->region, | |
395 | sizeof(fe->region), | |
396 | NULL, NULL); | |
397 | if (r) | |
398 | goto fail; | |
399 | } | |
400 | ||
401 | list_for_each_entry(fe, &clear_list, list) { | |
f5db4af4 JB |
402 | r = userspace_do_request(lc, lc->uuid, fe->type, |
403 | (char *)&fe->region, | |
404 | sizeof(fe->region), | |
405 | NULL, NULL); | |
406 | if (r) | |
407 | goto fail; | |
408 | } | |
409 | ||
410 | r = userspace_do_request(lc, lc->uuid, DM_ULOG_FLUSH, | |
411 | NULL, 0, NULL, NULL); | |
412 | ||
413 | fail: | |
414 | /* | |
415 | * We can safely remove these entries, even if failure. | |
416 | * Calling code will receive an error and will know that | |
417 | * the log facility has failed. | |
418 | */ | |
909cc4fb JB |
419 | list_for_each_entry_safe(fe, tmp_fe, &mark_list, list) { |
420 | list_del(&fe->list); | |
421 | mempool_free(fe, flush_entry_pool); | |
422 | } | |
423 | list_for_each_entry_safe(fe, tmp_fe, &clear_list, list) { | |
f5db4af4 JB |
424 | list_del(&fe->list); |
425 | mempool_free(fe, flush_entry_pool); | |
426 | } | |
427 | ||
428 | if (r) | |
429 | dm_table_event(lc->ti->table); | |
430 | ||
431 | return r; | |
432 | } | |
433 | ||
434 | /* | |
435 | * userspace_mark_region | |
436 | * | |
437 | * This function should avoid blocking unless absolutely required. | |
438 | * (Memory allocation is valid for blocking.) | |
439 | */ | |
440 | static void userspace_mark_region(struct dm_dirty_log *log, region_t region) | |
441 | { | |
442 | unsigned long flags; | |
443 | struct log_c *lc = log->context; | |
444 | struct flush_entry *fe; | |
445 | ||
446 | /* Wait for an allocation, but _never_ fail */ | |
447 | fe = mempool_alloc(flush_entry_pool, GFP_NOIO); | |
448 | BUG_ON(!fe); | |
449 | ||
450 | spin_lock_irqsave(&lc->flush_lock, flags); | |
451 | fe->type = DM_ULOG_MARK_REGION; | |
452 | fe->region = region; | |
909cc4fb | 453 | list_add(&fe->list, &lc->mark_list); |
f5db4af4 JB |
454 | spin_unlock_irqrestore(&lc->flush_lock, flags); |
455 | ||
456 | return; | |
457 | } | |
458 | ||
459 | /* | |
460 | * userspace_clear_region | |
461 | * | |
462 | * This function must not block. | |
463 | * So, the alloc can't block. In the worst case, it is ok to | |
464 | * fail. It would simply mean we can't clear the region. | |
465 | * Does nothing to current sync context, but does mean | |
466 | * the region will be re-sync'ed on a reload of the mirror | |
467 | * even though it is in-sync. | |
468 | */ | |
469 | static void userspace_clear_region(struct dm_dirty_log *log, region_t region) | |
470 | { | |
471 | unsigned long flags; | |
472 | struct log_c *lc = log->context; | |
473 | struct flush_entry *fe; | |
474 | ||
475 | /* | |
476 | * If we fail to allocate, we skip the clearing of | |
477 | * the region. This doesn't hurt us in any way, except | |
478 | * to cause the region to be resync'ed when the | |
479 | * device is activated next time. | |
480 | */ | |
481 | fe = mempool_alloc(flush_entry_pool, GFP_ATOMIC); | |
482 | if (!fe) { | |
483 | DMERR("Failed to allocate memory to clear region."); | |
484 | return; | |
485 | } | |
486 | ||
487 | spin_lock_irqsave(&lc->flush_lock, flags); | |
488 | fe->type = DM_ULOG_CLEAR_REGION; | |
489 | fe->region = region; | |
909cc4fb | 490 | list_add(&fe->list, &lc->clear_list); |
f5db4af4 JB |
491 | spin_unlock_irqrestore(&lc->flush_lock, flags); |
492 | ||
493 | return; | |
494 | } | |
495 | ||
496 | /* | |
497 | * userspace_get_resync_work | |
498 | * | |
499 | * Get a region that needs recovery. It is valid to return | |
500 | * an error for this function. | |
501 | * | |
502 | * Returns: 1 if region filled, 0 if no work, <0 on error | |
503 | */ | |
504 | static int userspace_get_resync_work(struct dm_dirty_log *log, region_t *region) | |
505 | { | |
506 | int r; | |
507 | size_t rdata_size; | |
508 | struct log_c *lc = log->context; | |
509 | struct { | |
510 | int64_t i; /* 64-bit for mix arch compatibility */ | |
511 | region_t r; | |
512 | } pkg; | |
513 | ||
514 | if (lc->in_sync_hint >= lc->region_count) | |
515 | return 0; | |
516 | ||
517 | rdata_size = sizeof(pkg); | |
518 | r = userspace_do_request(lc, lc->uuid, DM_ULOG_GET_RESYNC_WORK, | |
519 | NULL, 0, | |
520 | (char *)&pkg, &rdata_size); | |
521 | ||
522 | *region = pkg.r; | |
523 | return (r) ? r : (int)pkg.i; | |
524 | } | |
525 | ||
526 | /* | |
527 | * userspace_set_region_sync | |
528 | * | |
529 | * Set the sync status of a given region. This function | |
530 | * must not fail. | |
531 | */ | |
532 | static void userspace_set_region_sync(struct dm_dirty_log *log, | |
533 | region_t region, int in_sync) | |
534 | { | |
535 | int r; | |
536 | struct log_c *lc = log->context; | |
537 | struct { | |
538 | region_t r; | |
539 | int64_t i; | |
540 | } pkg; | |
541 | ||
542 | pkg.r = region; | |
543 | pkg.i = (int64_t)in_sync; | |
544 | ||
545 | r = userspace_do_request(lc, lc->uuid, DM_ULOG_SET_REGION_SYNC, | |
546 | (char *)&pkg, sizeof(pkg), | |
547 | NULL, NULL); | |
548 | ||
549 | /* | |
550 | * It would be nice to be able to report failures. | |
551 | * However, it is easy emough to detect and resolve. | |
552 | */ | |
553 | return; | |
554 | } | |
555 | ||
556 | /* | |
557 | * userspace_get_sync_count | |
558 | * | |
559 | * If there is any sort of failure when consulting the server, | |
560 | * we assume that the sync count is zero. | |
561 | * | |
562 | * Returns: sync count on success, 0 on failure | |
563 | */ | |
564 | static region_t userspace_get_sync_count(struct dm_dirty_log *log) | |
565 | { | |
566 | int r; | |
567 | size_t rdata_size; | |
568 | uint64_t sync_count; | |
569 | struct log_c *lc = log->context; | |
570 | ||
571 | rdata_size = sizeof(sync_count); | |
572 | r = userspace_do_request(lc, lc->uuid, DM_ULOG_GET_SYNC_COUNT, | |
573 | NULL, 0, | |
574 | (char *)&sync_count, &rdata_size); | |
575 | ||
576 | if (r) | |
577 | return 0; | |
578 | ||
579 | if (sync_count >= lc->region_count) | |
580 | lc->in_sync_hint = lc->region_count; | |
581 | ||
582 | return (region_t)sync_count; | |
583 | } | |
584 | ||
585 | /* | |
586 | * userspace_status | |
587 | * | |
588 | * Returns: amount of space consumed | |
589 | */ | |
590 | static int userspace_status(struct dm_dirty_log *log, status_type_t status_type, | |
591 | char *result, unsigned maxlen) | |
592 | { | |
593 | int r = 0; | |
b8313b6d | 594 | char *table_args; |
f5db4af4 JB |
595 | size_t sz = (size_t)maxlen; |
596 | struct log_c *lc = log->context; | |
597 | ||
598 | switch (status_type) { | |
599 | case STATUSTYPE_INFO: | |
600 | r = userspace_do_request(lc, lc->uuid, DM_ULOG_STATUS_INFO, | |
601 | NULL, 0, | |
602 | result, &sz); | |
603 | ||
604 | if (r) { | |
605 | sz = 0; | |
606 | DMEMIT("%s 1 COM_FAILURE", log->type->name); | |
607 | } | |
608 | break; | |
609 | case STATUSTYPE_TABLE: | |
610 | sz = 0; | |
0d03d59d | 611 | table_args = strchr(lc->usr_argv_str, ' '); |
b8313b6d JB |
612 | BUG_ON(!table_args); /* There will always be a ' ' */ |
613 | table_args++; | |
614 | ||
615 | DMEMIT("%s %u %s %s ", log->type->name, lc->usr_argc, | |
616 | lc->uuid, table_args); | |
f5db4af4 JB |
617 | break; |
618 | } | |
619 | return (r) ? 0 : (int)sz; | |
620 | } | |
621 | ||
622 | /* | |
623 | * userspace_is_remote_recovering | |
624 | * | |
625 | * Returns: 1 if region recovering, 0 otherwise | |
626 | */ | |
627 | static int userspace_is_remote_recovering(struct dm_dirty_log *log, | |
628 | region_t region) | |
629 | { | |
630 | int r; | |
631 | uint64_t region64 = region; | |
632 | struct log_c *lc = log->context; | |
633 | static unsigned long long limit; | |
634 | struct { | |
635 | int64_t is_recovering; | |
636 | uint64_t in_sync_hint; | |
637 | } pkg; | |
638 | size_t rdata_size = sizeof(pkg); | |
639 | ||
640 | /* | |
641 | * Once the mirror has been reported to be in-sync, | |
642 | * it will never again ask for recovery work. So, | |
643 | * we can safely say there is not a remote machine | |
644 | * recovering if the device is in-sync. (in_sync_hint | |
645 | * must be reset at resume time.) | |
646 | */ | |
647 | if (region < lc->in_sync_hint) | |
648 | return 0; | |
649 | else if (jiffies < limit) | |
650 | return 1; | |
651 | ||
652 | limit = jiffies + (HZ / 4); | |
653 | r = userspace_do_request(lc, lc->uuid, DM_ULOG_IS_REMOTE_RECOVERING, | |
654 | (char *)®ion64, sizeof(region64), | |
655 | (char *)&pkg, &rdata_size); | |
656 | if (r) | |
657 | return 1; | |
658 | ||
659 | lc->in_sync_hint = pkg.in_sync_hint; | |
660 | ||
661 | return (int)pkg.is_recovering; | |
662 | } | |
663 | ||
664 | static struct dm_dirty_log_type _userspace_type = { | |
665 | .name = "userspace", | |
666 | .module = THIS_MODULE, | |
667 | .ctr = userspace_ctr, | |
668 | .dtr = userspace_dtr, | |
669 | .presuspend = userspace_presuspend, | |
670 | .postsuspend = userspace_postsuspend, | |
671 | .resume = userspace_resume, | |
672 | .get_region_size = userspace_get_region_size, | |
673 | .is_clean = userspace_is_clean, | |
674 | .in_sync = userspace_in_sync, | |
675 | .flush = userspace_flush, | |
676 | .mark_region = userspace_mark_region, | |
677 | .clear_region = userspace_clear_region, | |
678 | .get_resync_work = userspace_get_resync_work, | |
679 | .set_region_sync = userspace_set_region_sync, | |
680 | .get_sync_count = userspace_get_sync_count, | |
681 | .status = userspace_status, | |
682 | .is_remote_recovering = userspace_is_remote_recovering, | |
683 | }; | |
684 | ||
685 | static int __init userspace_dirty_log_init(void) | |
686 | { | |
687 | int r = 0; | |
688 | ||
689 | flush_entry_pool = mempool_create(100, flush_entry_alloc, | |
690 | flush_entry_free, NULL); | |
691 | ||
692 | if (!flush_entry_pool) { | |
693 | DMWARN("Unable to create flush_entry_pool: No memory."); | |
694 | return -ENOMEM; | |
695 | } | |
696 | ||
697 | r = dm_ulog_tfr_init(); | |
698 | if (r) { | |
699 | DMWARN("Unable to initialize userspace log communications"); | |
700 | mempool_destroy(flush_entry_pool); | |
701 | return r; | |
702 | } | |
703 | ||
704 | r = dm_dirty_log_type_register(&_userspace_type); | |
705 | if (r) { | |
706 | DMWARN("Couldn't register userspace dirty log type"); | |
707 | dm_ulog_tfr_exit(); | |
708 | mempool_destroy(flush_entry_pool); | |
709 | return r; | |
710 | } | |
711 | ||
712 | DMINFO("version 1.0.0 loaded"); | |
713 | return 0; | |
714 | } | |
715 | ||
716 | static void __exit userspace_dirty_log_exit(void) | |
717 | { | |
718 | dm_dirty_log_type_unregister(&_userspace_type); | |
719 | dm_ulog_tfr_exit(); | |
720 | mempool_destroy(flush_entry_pool); | |
721 | ||
722 | DMINFO("version 1.0.0 unloaded"); | |
723 | return; | |
724 | } | |
725 | ||
726 | module_init(userspace_dirty_log_init); | |
727 | module_exit(userspace_dirty_log_exit); | |
728 | ||
729 | MODULE_DESCRIPTION(DM_NAME " userspace dirty log link"); | |
730 | MODULE_AUTHOR("Jonathan Brassow <dm-devel@redhat.com>"); | |
731 | MODULE_LICENSE("GPL"); |