Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2003 Sistina Software | |
b7fd54a7 | 3 | * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. |
1da177e4 LT |
4 | * |
5 | * This file is released under the LGPL. | |
6 | */ | |
7 | ||
8 | #include <linux/init.h> | |
9 | #include <linux/slab.h> | |
10 | #include <linux/module.h> | |
11 | #include <linux/vmalloc.h> | |
a765e20e AK |
12 | #include <linux/dm-io.h> |
13 | #include <linux/dm-dirty-log.h> | |
1da177e4 | 14 | |
586e80e6 | 15 | #include <linux/device-mapper.h> |
1da177e4 | 16 | |
b7fd54a7 | 17 | #define DM_MSG_PREFIX "dirty region log" |
72d94861 | 18 | |
1da177e4 LT |
19 | static LIST_HEAD(_log_types); |
20 | static DEFINE_SPINLOCK(_lock); | |
21 | ||
ec44ab9d | 22 | static struct dm_dirty_log_type *__find_dirty_log_type(const char *name) |
1da177e4 | 23 | { |
ec44ab9d | 24 | struct dm_dirty_log_type *log_type; |
2a23aa1d JB |
25 | |
26 | list_for_each_entry(log_type, &_log_types, list) | |
ec44ab9d | 27 | if (!strcmp(name, log_type->name)) |
2a23aa1d JB |
28 | return log_type; |
29 | ||
30 | return NULL; | |
31 | } | |
32 | ||
ec44ab9d | 33 | static struct dm_dirty_log_type *_get_dirty_log_type(const char *name) |
2a23aa1d | 34 | { |
ec44ab9d | 35 | struct dm_dirty_log_type *log_type; |
1da177e4 LT |
36 | |
37 | spin_lock(&_lock); | |
2a23aa1d JB |
38 | |
39 | log_type = __find_dirty_log_type(name); | |
ec44ab9d | 40 | if (log_type && !try_module_get(log_type->module)) |
84e67c93 | 41 | log_type = NULL; |
1da177e4 LT |
42 | |
43 | spin_unlock(&_lock); | |
2a23aa1d JB |
44 | |
45 | return log_type; | |
1da177e4 LT |
46 | } |
47 | ||
fb8b2848 JB |
48 | /* |
49 | * get_type | |
50 | * @type_name | |
51 | * | |
2a23aa1d | 52 | * Attempt to retrieve the dm_dirty_log_type by name. If not already |
fb8b2848 JB |
53 | * available, attempt to load the appropriate module. |
54 | * | |
55 | * Log modules are named "dm-log-" followed by the 'type_name'. | |
56 | * Modules may contain multiple types. | |
57 | * This function will first try the module "dm-log-<type_name>", | |
58 | * then truncate 'type_name' on the last '-' and try again. | |
59 | * | |
60 | * For example, if type_name was "clustered-disk", it would search | |
61 | * 'dm-log-clustered-disk' then 'dm-log-clustered'. | |
62 | * | |
63 | * Returns: dirty_log_type* on success, NULL on failure | |
64 | */ | |
416cd17b | 65 | static struct dm_dirty_log_type *get_type(const char *type_name) |
fb8b2848 JB |
66 | { |
67 | char *p, *type_name_dup; | |
ec44ab9d | 68 | struct dm_dirty_log_type *log_type; |
fb8b2848 | 69 | |
2a23aa1d JB |
70 | if (!type_name) |
71 | return NULL; | |
72 | ||
73 | log_type = _get_dirty_log_type(type_name); | |
74 | if (log_type) | |
ec44ab9d | 75 | return log_type; |
fb8b2848 JB |
76 | |
77 | type_name_dup = kstrdup(type_name, GFP_KERNEL); | |
78 | if (!type_name_dup) { | |
79 | DMWARN("No memory left to attempt log module load for \"%s\"", | |
80 | type_name); | |
81 | return NULL; | |
82 | } | |
83 | ||
84 | while (request_module("dm-log-%s", type_name_dup) || | |
2a23aa1d | 85 | !(log_type = _get_dirty_log_type(type_name))) { |
fb8b2848 JB |
86 | p = strrchr(type_name_dup, '-'); |
87 | if (!p) | |
88 | break; | |
89 | p[0] = '\0'; | |
90 | } | |
91 | ||
2a23aa1d | 92 | if (!log_type) |
fb8b2848 JB |
93 | DMWARN("Module for logging type \"%s\" not found.", type_name); |
94 | ||
95 | kfree(type_name_dup); | |
96 | ||
ec44ab9d | 97 | return log_type; |
fb8b2848 JB |
98 | } |
99 | ||
416cd17b | 100 | static void put_type(struct dm_dirty_log_type *type) |
1da177e4 | 101 | { |
2a23aa1d JB |
102 | if (!type) |
103 | return; | |
104 | ||
1da177e4 | 105 | spin_lock(&_lock); |
ec44ab9d | 106 | if (!__find_dirty_log_type(type->name)) |
2a23aa1d JB |
107 | goto out; |
108 | ||
84e67c93 | 109 | module_put(type->module); |
2a23aa1d JB |
110 | |
111 | out: | |
1da177e4 LT |
112 | spin_unlock(&_lock); |
113 | } | |
114 | ||
b8206bc3 AK |
115 | int dm_dirty_log_type_register(struct dm_dirty_log_type *type) |
116 | { | |
2a23aa1d JB |
117 | int r = 0; |
118 | ||
b8206bc3 | 119 | spin_lock(&_lock); |
2a23aa1d | 120 | if (!__find_dirty_log_type(type->name)) |
ec44ab9d MS |
121 | list_add(&type->list, &_log_types); |
122 | else | |
2a23aa1d | 123 | r = -EEXIST; |
b8206bc3 AK |
124 | spin_unlock(&_lock); |
125 | ||
2a23aa1d | 126 | return r; |
b8206bc3 AK |
127 | } |
128 | EXPORT_SYMBOL(dm_dirty_log_type_register); | |
129 | ||
130 | int dm_dirty_log_type_unregister(struct dm_dirty_log_type *type) | |
131 | { | |
132 | spin_lock(&_lock); | |
133 | ||
ec44ab9d | 134 | if (!__find_dirty_log_type(type->name)) { |
2a23aa1d JB |
135 | spin_unlock(&_lock); |
136 | return -EINVAL; | |
137 | } | |
138 | ||
ec44ab9d | 139 | list_del(&type->list); |
b8206bc3 AK |
140 | |
141 | spin_unlock(&_lock); | |
142 | ||
143 | return 0; | |
144 | } | |
145 | EXPORT_SYMBOL(dm_dirty_log_type_unregister); | |
146 | ||
416cd17b HM |
147 | struct dm_dirty_log *dm_dirty_log_create(const char *type_name, |
148 | struct dm_target *ti, | |
149 | unsigned int argc, char **argv) | |
1da177e4 | 150 | { |
416cd17b HM |
151 | struct dm_dirty_log_type *type; |
152 | struct dm_dirty_log *log; | |
1da177e4 LT |
153 | |
154 | log = kmalloc(sizeof(*log), GFP_KERNEL); | |
155 | if (!log) | |
156 | return NULL; | |
157 | ||
158 | type = get_type(type_name); | |
159 | if (!type) { | |
160 | kfree(log); | |
161 | return NULL; | |
162 | } | |
163 | ||
164 | log->type = type; | |
165 | if (type->ctr(log, ti, argc, argv)) { | |
166 | kfree(log); | |
167 | put_type(type); | |
168 | return NULL; | |
169 | } | |
170 | ||
171 | return log; | |
172 | } | |
416cd17b | 173 | EXPORT_SYMBOL(dm_dirty_log_create); |
1da177e4 | 174 | |
416cd17b | 175 | void dm_dirty_log_destroy(struct dm_dirty_log *log) |
1da177e4 LT |
176 | { |
177 | log->type->dtr(log); | |
178 | put_type(log->type); | |
179 | kfree(log); | |
180 | } | |
416cd17b | 181 | EXPORT_SYMBOL(dm_dirty_log_destroy); |
1da177e4 LT |
182 | |
183 | /*----------------------------------------------------------------- | |
184 | * Persistent and core logs share a lot of their implementation. | |
185 | * FIXME: need a reload method to be called from a resume | |
186 | *---------------------------------------------------------------*/ | |
187 | /* | |
188 | * Magic for persistent mirrors: "MiRr" | |
189 | */ | |
190 | #define MIRROR_MAGIC 0x4D695272 | |
191 | ||
192 | /* | |
193 | * The on-disk version of the metadata. | |
194 | */ | |
a4fc4717 | 195 | #define MIRROR_DISK_VERSION 2 |
1da177e4 LT |
196 | #define LOG_OFFSET 2 |
197 | ||
198 | struct log_header { | |
199 | uint32_t magic; | |
200 | ||
201 | /* | |
202 | * Simple, incrementing version. no backward | |
203 | * compatibility. | |
204 | */ | |
205 | uint32_t version; | |
206 | sector_t nr_regions; | |
207 | }; | |
208 | ||
209 | struct log_c { | |
210 | struct dm_target *ti; | |
b09acf1a MP |
211 | int touched_dirtied; |
212 | int touched_cleaned; | |
1da177e4 LT |
213 | uint32_t region_size; |
214 | unsigned int region_count; | |
215 | region_t sync_count; | |
216 | ||
217 | unsigned bitset_uint32_count; | |
218 | uint32_t *clean_bits; | |
219 | uint32_t *sync_bits; | |
220 | uint32_t *recovering_bits; /* FIXME: this seems excessive */ | |
221 | ||
222 | int sync_search; | |
223 | ||
224 | /* Resync flag */ | |
225 | enum sync { | |
226 | DEFAULTSYNC, /* Synchronize if necessary */ | |
227 | NOSYNC, /* Devices known to be already in sync */ | |
228 | FORCESYNC, /* Force a sync to happen */ | |
229 | } sync; | |
230 | ||
5d234d1e HM |
231 | struct dm_io_request io_req; |
232 | ||
1da177e4 LT |
233 | /* |
234 | * Disk log fields | |
235 | */ | |
01d03a66 | 236 | int log_dev_failed; |
1da177e4 LT |
237 | struct dm_dev *log_dev; |
238 | struct log_header header; | |
239 | ||
22a1ceb1 | 240 | struct dm_io_region header_location; |
1da177e4 | 241 | struct log_header *disk_header; |
1da177e4 LT |
242 | }; |
243 | ||
244 | /* | |
245 | * The touched member needs to be updated every time we access | |
246 | * one of the bitsets. | |
247 | */ | |
416cd17b | 248 | static inline int log_test_bit(uint32_t *bs, unsigned bit) |
1da177e4 | 249 | { |
a4fc4717 | 250 | return ext2_test_bit(bit, (unsigned long *) bs) ? 1 : 0; |
1da177e4 LT |
251 | } |
252 | ||
253 | static inline void log_set_bit(struct log_c *l, | |
254 | uint32_t *bs, unsigned bit) | |
255 | { | |
a4fc4717 | 256 | ext2_set_bit(bit, (unsigned long *) bs); |
b09acf1a | 257 | l->touched_cleaned = 1; |
1da177e4 LT |
258 | } |
259 | ||
260 | static inline void log_clear_bit(struct log_c *l, | |
261 | uint32_t *bs, unsigned bit) | |
262 | { | |
a4fc4717 | 263 | ext2_clear_bit(bit, (unsigned long *) bs); |
b09acf1a | 264 | l->touched_dirtied = 1; |
1da177e4 LT |
265 | } |
266 | ||
267 | /*---------------------------------------------------------------- | |
268 | * Header IO | |
269 | *--------------------------------------------------------------*/ | |
270 | static void header_to_disk(struct log_header *core, struct log_header *disk) | |
271 | { | |
272 | disk->magic = cpu_to_le32(core->magic); | |
273 | disk->version = cpu_to_le32(core->version); | |
274 | disk->nr_regions = cpu_to_le64(core->nr_regions); | |
275 | } | |
276 | ||
277 | static void header_from_disk(struct log_header *core, struct log_header *disk) | |
278 | { | |
279 | core->magic = le32_to_cpu(disk->magic); | |
280 | core->version = le32_to_cpu(disk->version); | |
281 | core->nr_regions = le64_to_cpu(disk->nr_regions); | |
282 | } | |
283 | ||
5d234d1e HM |
284 | static int rw_header(struct log_c *lc, int rw) |
285 | { | |
286 | lc->io_req.bi_rw = rw; | |
5d234d1e HM |
287 | |
288 | return dm_io(&lc->io_req, 1, &lc->header_location, NULL); | |
289 | } | |
290 | ||
1da177e4 LT |
291 | static int read_header(struct log_c *log) |
292 | { | |
293 | int r; | |
1da177e4 | 294 | |
5d234d1e | 295 | r = rw_header(log, READ); |
1da177e4 LT |
296 | if (r) |
297 | return r; | |
298 | ||
299 | header_from_disk(&log->header, log->disk_header); | |
300 | ||
301 | /* New log required? */ | |
302 | if (log->sync != DEFAULTSYNC || log->header.magic != MIRROR_MAGIC) { | |
303 | log->header.magic = MIRROR_MAGIC; | |
304 | log->header.version = MIRROR_DISK_VERSION; | |
305 | log->header.nr_regions = 0; | |
306 | } | |
307 | ||
a4fc4717 PC |
308 | #ifdef __LITTLE_ENDIAN |
309 | if (log->header.version == 1) | |
310 | log->header.version = 2; | |
311 | #endif | |
312 | ||
1da177e4 LT |
313 | if (log->header.version != MIRROR_DISK_VERSION) { |
314 | DMWARN("incompatible disk log version"); | |
315 | return -EINVAL; | |
316 | } | |
317 | ||
318 | return 0; | |
319 | } | |
320 | ||
2045e88e MB |
321 | static int _check_region_size(struct dm_target *ti, uint32_t region_size) |
322 | { | |
323 | if (region_size < 2 || region_size > ti->len) | |
324 | return 0; | |
325 | ||
326 | if (!is_power_of_2(region_size)) | |
327 | return 0; | |
328 | ||
329 | return 1; | |
330 | } | |
331 | ||
1da177e4 LT |
332 | /*---------------------------------------------------------------- |
333 | * core log constructor/destructor | |
334 | * | |
335 | * argv contains region_size followed optionally by [no]sync | |
336 | *--------------------------------------------------------------*/ | |
337 | #define BYTE_SHIFT 3 | |
416cd17b | 338 | static int create_log_context(struct dm_dirty_log *log, struct dm_target *ti, |
b7cca195 AK |
339 | unsigned int argc, char **argv, |
340 | struct dm_dev *dev) | |
1da177e4 LT |
341 | { |
342 | enum sync sync = DEFAULTSYNC; | |
343 | ||
344 | struct log_c *lc; | |
345 | uint32_t region_size; | |
346 | unsigned int region_count; | |
b7cca195 | 347 | size_t bitset_size, buf_size; |
5d234d1e | 348 | int r; |
1da177e4 LT |
349 | |
350 | if (argc < 1 || argc > 2) { | |
b7fd54a7 | 351 | DMWARN("wrong number of arguments to dirty region log"); |
1da177e4 LT |
352 | return -EINVAL; |
353 | } | |
354 | ||
355 | if (argc > 1) { | |
356 | if (!strcmp(argv[1], "sync")) | |
357 | sync = FORCESYNC; | |
358 | else if (!strcmp(argv[1], "nosync")) | |
359 | sync = NOSYNC; | |
360 | else { | |
b7fd54a7 HM |
361 | DMWARN("unrecognised sync argument to " |
362 | "dirty region log: %s", argv[1]); | |
1da177e4 LT |
363 | return -EINVAL; |
364 | } | |
365 | } | |
366 | ||
2045e88e MB |
367 | if (sscanf(argv[0], "%u", ®ion_size) != 1 || |
368 | !_check_region_size(ti, region_size)) { | |
369 | DMWARN("invalid region size %s", argv[0]); | |
1da177e4 LT |
370 | return -EINVAL; |
371 | } | |
372 | ||
373 | region_count = dm_sector_div_up(ti->len, region_size); | |
374 | ||
375 | lc = kmalloc(sizeof(*lc), GFP_KERNEL); | |
376 | if (!lc) { | |
377 | DMWARN("couldn't allocate core log"); | |
378 | return -ENOMEM; | |
379 | } | |
380 | ||
381 | lc->ti = ti; | |
b09acf1a MP |
382 | lc->touched_dirtied = 0; |
383 | lc->touched_cleaned = 0; | |
1da177e4 LT |
384 | lc->region_size = region_size; |
385 | lc->region_count = region_count; | |
386 | lc->sync = sync; | |
387 | ||
388 | /* | |
0e56822d | 389 | * Work out how many "unsigned long"s we need to hold the bitset. |
1da177e4 LT |
390 | */ |
391 | bitset_size = dm_round_up(region_count, | |
29121bd0 | 392 | sizeof(*lc->clean_bits) << BYTE_SHIFT); |
1da177e4 LT |
393 | bitset_size >>= BYTE_SHIFT; |
394 | ||
29121bd0 | 395 | lc->bitset_uint32_count = bitset_size / sizeof(*lc->clean_bits); |
b7cca195 AK |
396 | |
397 | /* | |
398 | * Disk log? | |
399 | */ | |
400 | if (!dev) { | |
401 | lc->clean_bits = vmalloc(bitset_size); | |
402 | if (!lc->clean_bits) { | |
403 | DMWARN("couldn't allocate clean bitset"); | |
404 | kfree(lc); | |
405 | return -ENOMEM; | |
406 | } | |
407 | lc->disk_header = NULL; | |
408 | } else { | |
409 | lc->log_dev = dev; | |
01d03a66 | 410 | lc->log_dev_failed = 0; |
b7cca195 AK |
411 | lc->header_location.bdev = lc->log_dev->bdev; |
412 | lc->header_location.sector = 0; | |
413 | ||
414 | /* | |
415 | * Buffer holds both header and bitset. | |
416 | */ | |
18d8594d MS |
417 | buf_size = |
418 | dm_round_up((LOG_OFFSET << SECTOR_SHIFT) + bitset_size, | |
419 | bdev_logical_block_size(lc->header_location. | |
420 | bdev)); | |
ac1f0ac2 | 421 | |
5657e8fa | 422 | if (buf_size > i_size_read(dev->bdev->bd_inode)) { |
ac1f0ac2 MB |
423 | DMWARN("log device %s too small: need %llu bytes", |
424 | dev->name, (unsigned long long)buf_size); | |
425 | kfree(lc); | |
426 | return -EINVAL; | |
427 | } | |
428 | ||
b7cca195 | 429 | lc->header_location.count = buf_size >> SECTOR_SHIFT; |
6f3af01c | 430 | |
5d234d1e | 431 | lc->io_req.mem.type = DM_IO_VMA; |
6f3af01c | 432 | lc->io_req.notify.fn = NULL; |
5d234d1e HM |
433 | lc->io_req.client = dm_io_client_create(dm_div_up(buf_size, |
434 | PAGE_SIZE)); | |
435 | if (IS_ERR(lc->io_req.client)) { | |
436 | r = PTR_ERR(lc->io_req.client); | |
437 | DMWARN("couldn't allocate disk io client"); | |
438 | kfree(lc); | |
439 | return -ENOMEM; | |
440 | } | |
b7cca195 AK |
441 | |
442 | lc->disk_header = vmalloc(buf_size); | |
443 | if (!lc->disk_header) { | |
444 | DMWARN("couldn't allocate disk log buffer"); | |
c7a2bd19 | 445 | dm_io_client_destroy(lc->io_req.client); |
b7cca195 AK |
446 | kfree(lc); |
447 | return -ENOMEM; | |
448 | } | |
449 | ||
6f3af01c | 450 | lc->io_req.mem.ptr.vma = lc->disk_header; |
b7cca195 AK |
451 | lc->clean_bits = (void *)lc->disk_header + |
452 | (LOG_OFFSET << SECTOR_SHIFT); | |
1da177e4 | 453 | } |
b7cca195 | 454 | |
1da177e4 LT |
455 | memset(lc->clean_bits, -1, bitset_size); |
456 | ||
457 | lc->sync_bits = vmalloc(bitset_size); | |
458 | if (!lc->sync_bits) { | |
459 | DMWARN("couldn't allocate sync bitset"); | |
b7cca195 AK |
460 | if (!dev) |
461 | vfree(lc->clean_bits); | |
c7a2bd19 TY |
462 | else |
463 | dm_io_client_destroy(lc->io_req.client); | |
b7cca195 | 464 | vfree(lc->disk_header); |
1da177e4 LT |
465 | kfree(lc); |
466 | return -ENOMEM; | |
467 | } | |
468 | memset(lc->sync_bits, (sync == NOSYNC) ? -1 : 0, bitset_size); | |
469 | lc->sync_count = (sync == NOSYNC) ? region_count : 0; | |
470 | ||
471 | lc->recovering_bits = vmalloc(bitset_size); | |
472 | if (!lc->recovering_bits) { | |
473 | DMWARN("couldn't allocate sync bitset"); | |
474 | vfree(lc->sync_bits); | |
b7cca195 AK |
475 | if (!dev) |
476 | vfree(lc->clean_bits); | |
c7a2bd19 TY |
477 | else |
478 | dm_io_client_destroy(lc->io_req.client); | |
b7cca195 | 479 | vfree(lc->disk_header); |
1da177e4 LT |
480 | kfree(lc); |
481 | return -ENOMEM; | |
482 | } | |
483 | memset(lc->recovering_bits, 0, bitset_size); | |
484 | lc->sync_search = 0; | |
485 | log->context = lc; | |
b7cca195 | 486 | |
1da177e4 LT |
487 | return 0; |
488 | } | |
489 | ||
416cd17b | 490 | static int core_ctr(struct dm_dirty_log *log, struct dm_target *ti, |
b7cca195 AK |
491 | unsigned int argc, char **argv) |
492 | { | |
493 | return create_log_context(log, ti, argc, argv, NULL); | |
494 | } | |
495 | ||
496 | static void destroy_log_context(struct log_c *lc) | |
1da177e4 | 497 | { |
1da177e4 LT |
498 | vfree(lc->sync_bits); |
499 | vfree(lc->recovering_bits); | |
500 | kfree(lc); | |
501 | } | |
502 | ||
416cd17b | 503 | static void core_dtr(struct dm_dirty_log *log) |
b7cca195 AK |
504 | { |
505 | struct log_c *lc = (struct log_c *) log->context; | |
506 | ||
507 | vfree(lc->clean_bits); | |
508 | destroy_log_context(lc); | |
509 | } | |
510 | ||
1da177e4 LT |
511 | /*---------------------------------------------------------------- |
512 | * disk log constructor/destructor | |
513 | * | |
514 | * argv contains log_device region_size followed optionally by [no]sync | |
515 | *--------------------------------------------------------------*/ | |
416cd17b | 516 | static int disk_ctr(struct dm_dirty_log *log, struct dm_target *ti, |
1da177e4 LT |
517 | unsigned int argc, char **argv) |
518 | { | |
519 | int r; | |
1da177e4 LT |
520 | struct dm_dev *dev; |
521 | ||
522 | if (argc < 2 || argc > 3) { | |
b7fd54a7 | 523 | DMWARN("wrong number of arguments to disk dirty region log"); |
1da177e4 LT |
524 | return -EINVAL; |
525 | } | |
526 | ||
527 | r = dm_get_device(ti, argv[0], 0, 0 /* FIXME */, | |
528 | FMODE_READ | FMODE_WRITE, &dev); | |
529 | if (r) | |
530 | return r; | |
531 | ||
b7cca195 | 532 | r = create_log_context(log, ti, argc - 1, argv + 1, dev); |
1da177e4 LT |
533 | if (r) { |
534 | dm_put_device(ti, dev); | |
535 | return r; | |
536 | } | |
537 | ||
1da177e4 | 538 | return 0; |
1da177e4 LT |
539 | } |
540 | ||
416cd17b | 541 | static void disk_dtr(struct dm_dirty_log *log) |
1da177e4 LT |
542 | { |
543 | struct log_c *lc = (struct log_c *) log->context; | |
b7cca195 | 544 | |
1da177e4 LT |
545 | dm_put_device(lc->ti, lc->log_dev); |
546 | vfree(lc->disk_header); | |
5d234d1e | 547 | dm_io_client_destroy(lc->io_req.client); |
b7cca195 | 548 | destroy_log_context(lc); |
1da177e4 LT |
549 | } |
550 | ||
551 | static int count_bits32(uint32_t *addr, unsigned size) | |
552 | { | |
553 | int count = 0, i; | |
554 | ||
555 | for (i = 0; i < size; i++) { | |
556 | count += hweight32(*(addr+i)); | |
557 | } | |
558 | return count; | |
559 | } | |
560 | ||
01d03a66 JB |
561 | static void fail_log_device(struct log_c *lc) |
562 | { | |
563 | if (lc->log_dev_failed) | |
564 | return; | |
565 | ||
566 | lc->log_dev_failed = 1; | |
567 | dm_table_event(lc->ti->table); | |
568 | } | |
569 | ||
416cd17b | 570 | static int disk_resume(struct dm_dirty_log *log) |
1da177e4 LT |
571 | { |
572 | int r; | |
573 | unsigned i; | |
574 | struct log_c *lc = (struct log_c *) log->context; | |
575 | size_t size = lc->bitset_uint32_count * sizeof(uint32_t); | |
576 | ||
577 | /* read the disk header */ | |
578 | r = read_header(lc); | |
01d03a66 | 579 | if (r) { |
b7fd54a7 | 580 | DMWARN("%s: Failed to read header on dirty region log device", |
01d03a66 JB |
581 | lc->log_dev->name); |
582 | fail_log_device(lc); | |
ba8b45ce JB |
583 | /* |
584 | * If the log device cannot be read, we must assume | |
585 | * all regions are out-of-sync. If we simply return | |
586 | * here, the state will be uninitialized and could | |
587 | * lead us to return 'in-sync' status for regions | |
588 | * that are actually 'out-of-sync'. | |
589 | */ | |
590 | lc->header.nr_regions = 0; | |
01d03a66 | 591 | } |
1da177e4 | 592 | |
8a835f11 | 593 | /* set or clear any new bits -- device has grown */ |
1da177e4 LT |
594 | if (lc->sync == NOSYNC) |
595 | for (i = lc->header.nr_regions; i < lc->region_count; i++) | |
596 | /* FIXME: amazingly inefficient */ | |
597 | log_set_bit(lc, lc->clean_bits, i); | |
598 | else | |
599 | for (i = lc->header.nr_regions; i < lc->region_count; i++) | |
600 | /* FIXME: amazingly inefficient */ | |
601 | log_clear_bit(lc, lc->clean_bits, i); | |
602 | ||
8a835f11 AK |
603 | /* clear any old bits -- device has shrunk */ |
604 | for (i = lc->region_count; i % (sizeof(*lc->clean_bits) << BYTE_SHIFT); i++) | |
605 | log_clear_bit(lc, lc->clean_bits, i); | |
606 | ||
1da177e4 LT |
607 | /* copy clean across to sync */ |
608 | memcpy(lc->sync_bits, lc->clean_bits, size); | |
609 | lc->sync_count = count_bits32(lc->clean_bits, lc->bitset_uint32_count); | |
88b20a1a | 610 | lc->sync_search = 0; |
1da177e4 | 611 | |
1da177e4 LT |
612 | /* set the correct number of regions in the header */ |
613 | lc->header.nr_regions = lc->region_count; | |
614 | ||
6f3af01c TY |
615 | header_to_disk(&lc->header, lc->disk_header); |
616 | ||
1da177e4 | 617 | /* write the new header */ |
6f3af01c | 618 | r = rw_header(lc, WRITE); |
01d03a66 | 619 | if (r) { |
b7fd54a7 | 620 | DMWARN("%s: Failed to write header on dirty region log device", |
01d03a66 JB |
621 | lc->log_dev->name); |
622 | fail_log_device(lc); | |
623 | } | |
624 | ||
625 | return r; | |
1da177e4 LT |
626 | } |
627 | ||
416cd17b | 628 | static uint32_t core_get_region_size(struct dm_dirty_log *log) |
1da177e4 LT |
629 | { |
630 | struct log_c *lc = (struct log_c *) log->context; | |
631 | return lc->region_size; | |
632 | } | |
633 | ||
416cd17b | 634 | static int core_resume(struct dm_dirty_log *log) |
88b20a1a JB |
635 | { |
636 | struct log_c *lc = (struct log_c *) log->context; | |
637 | lc->sync_search = 0; | |
638 | return 0; | |
639 | } | |
640 | ||
416cd17b | 641 | static int core_is_clean(struct dm_dirty_log *log, region_t region) |
1da177e4 LT |
642 | { |
643 | struct log_c *lc = (struct log_c *) log->context; | |
644 | return log_test_bit(lc->clean_bits, region); | |
645 | } | |
646 | ||
416cd17b | 647 | static int core_in_sync(struct dm_dirty_log *log, region_t region, int block) |
1da177e4 LT |
648 | { |
649 | struct log_c *lc = (struct log_c *) log->context; | |
650 | return log_test_bit(lc->sync_bits, region); | |
651 | } | |
652 | ||
416cd17b | 653 | static int core_flush(struct dm_dirty_log *log) |
1da177e4 LT |
654 | { |
655 | /* no op */ | |
656 | return 0; | |
657 | } | |
658 | ||
416cd17b | 659 | static int disk_flush(struct dm_dirty_log *log) |
1da177e4 LT |
660 | { |
661 | int r; | |
662 | struct log_c *lc = (struct log_c *) log->context; | |
663 | ||
664 | /* only write if the log has changed */ | |
b09acf1a | 665 | if (!lc->touched_cleaned && !lc->touched_dirtied) |
1da177e4 LT |
666 | return 0; |
667 | ||
6f3af01c | 668 | r = rw_header(lc, WRITE); |
01d03a66 JB |
669 | if (r) |
670 | fail_log_device(lc); | |
b09acf1a MP |
671 | else { |
672 | lc->touched_dirtied = 0; | |
673 | lc->touched_cleaned = 0; | |
674 | } | |
1da177e4 LT |
675 | |
676 | return r; | |
677 | } | |
678 | ||
416cd17b | 679 | static void core_mark_region(struct dm_dirty_log *log, region_t region) |
1da177e4 LT |
680 | { |
681 | struct log_c *lc = (struct log_c *) log->context; | |
682 | log_clear_bit(lc, lc->clean_bits, region); | |
683 | } | |
684 | ||
416cd17b | 685 | static void core_clear_region(struct dm_dirty_log *log, region_t region) |
1da177e4 LT |
686 | { |
687 | struct log_c *lc = (struct log_c *) log->context; | |
688 | log_set_bit(lc, lc->clean_bits, region); | |
689 | } | |
690 | ||
416cd17b | 691 | static int core_get_resync_work(struct dm_dirty_log *log, region_t *region) |
1da177e4 LT |
692 | { |
693 | struct log_c *lc = (struct log_c *) log->context; | |
694 | ||
695 | if (lc->sync_search >= lc->region_count) | |
696 | return 0; | |
697 | ||
698 | do { | |
1113a7e9 SB |
699 | *region = ext2_find_next_zero_bit( |
700 | (unsigned long *) lc->sync_bits, | |
1da177e4 LT |
701 | lc->region_count, |
702 | lc->sync_search); | |
703 | lc->sync_search = *region + 1; | |
704 | ||
ac81b2ee | 705 | if (*region >= lc->region_count) |
1da177e4 LT |
706 | return 0; |
707 | ||
708 | } while (log_test_bit(lc->recovering_bits, *region)); | |
709 | ||
710 | log_set_bit(lc, lc->recovering_bits, *region); | |
711 | return 1; | |
712 | } | |
713 | ||
416cd17b | 714 | static void core_set_region_sync(struct dm_dirty_log *log, region_t region, |
f3ee6b2f | 715 | int in_sync) |
1da177e4 LT |
716 | { |
717 | struct log_c *lc = (struct log_c *) log->context; | |
718 | ||
719 | log_clear_bit(lc, lc->recovering_bits, region); | |
f3ee6b2f | 720 | if (in_sync) { |
1da177e4 LT |
721 | log_set_bit(lc, lc->sync_bits, region); |
722 | lc->sync_count++; | |
f3ee6b2f JB |
723 | } else if (log_test_bit(lc->sync_bits, region)) { |
724 | lc->sync_count--; | |
725 | log_clear_bit(lc, lc->sync_bits, region); | |
726 | } | |
1da177e4 LT |
727 | } |
728 | ||
416cd17b | 729 | static region_t core_get_sync_count(struct dm_dirty_log *log) |
1da177e4 LT |
730 | { |
731 | struct log_c *lc = (struct log_c *) log->context; | |
732 | ||
733 | return lc->sync_count; | |
734 | } | |
735 | ||
736 | #define DMEMIT_SYNC \ | |
737 | if (lc->sync != DEFAULTSYNC) \ | |
738 | DMEMIT("%ssync ", lc->sync == NOSYNC ? "no" : "") | |
739 | ||
416cd17b | 740 | static int core_status(struct dm_dirty_log *log, status_type_t status, |
1da177e4 LT |
741 | char *result, unsigned int maxlen) |
742 | { | |
743 | int sz = 0; | |
744 | struct log_c *lc = log->context; | |
745 | ||
746 | switch(status) { | |
747 | case STATUSTYPE_INFO: | |
315dcc22 | 748 | DMEMIT("1 %s", log->type->name); |
1da177e4 LT |
749 | break; |
750 | ||
751 | case STATUSTYPE_TABLE: | |
752 | DMEMIT("%s %u %u ", log->type->name, | |
753 | lc->sync == DEFAULTSYNC ? 1 : 2, lc->region_size); | |
754 | DMEMIT_SYNC; | |
755 | } | |
756 | ||
757 | return sz; | |
758 | } | |
759 | ||
416cd17b | 760 | static int disk_status(struct dm_dirty_log *log, status_type_t status, |
1da177e4 LT |
761 | char *result, unsigned int maxlen) |
762 | { | |
763 | int sz = 0; | |
1da177e4 LT |
764 | struct log_c *lc = log->context; |
765 | ||
766 | switch(status) { | |
767 | case STATUSTYPE_INFO: | |
315dcc22 JB |
768 | DMEMIT("3 %s %s %c", log->type->name, lc->log_dev->name, |
769 | lc->log_dev_failed ? 'D' : 'A'); | |
1da177e4 LT |
770 | break; |
771 | ||
772 | case STATUSTYPE_TABLE: | |
1da177e4 | 773 | DMEMIT("%s %u %s %u ", log->type->name, |
315dcc22 | 774 | lc->sync == DEFAULTSYNC ? 2 : 3, lc->log_dev->name, |
1da177e4 LT |
775 | lc->region_size); |
776 | DMEMIT_SYNC; | |
777 | } | |
778 | ||
779 | return sz; | |
780 | } | |
781 | ||
416cd17b | 782 | static struct dm_dirty_log_type _core_type = { |
1da177e4 LT |
783 | .name = "core", |
784 | .module = THIS_MODULE, | |
785 | .ctr = core_ctr, | |
786 | .dtr = core_dtr, | |
88b20a1a | 787 | .resume = core_resume, |
1da177e4 LT |
788 | .get_region_size = core_get_region_size, |
789 | .is_clean = core_is_clean, | |
790 | .in_sync = core_in_sync, | |
791 | .flush = core_flush, | |
792 | .mark_region = core_mark_region, | |
793 | .clear_region = core_clear_region, | |
794 | .get_resync_work = core_get_resync_work, | |
f3ee6b2f | 795 | .set_region_sync = core_set_region_sync, |
1da177e4 LT |
796 | .get_sync_count = core_get_sync_count, |
797 | .status = core_status, | |
798 | }; | |
799 | ||
416cd17b | 800 | static struct dm_dirty_log_type _disk_type = { |
1da177e4 LT |
801 | .name = "disk", |
802 | .module = THIS_MODULE, | |
803 | .ctr = disk_ctr, | |
804 | .dtr = disk_dtr, | |
6b3df0d7 | 805 | .postsuspend = disk_flush, |
1da177e4 LT |
806 | .resume = disk_resume, |
807 | .get_region_size = core_get_region_size, | |
808 | .is_clean = core_is_clean, | |
809 | .in_sync = core_in_sync, | |
810 | .flush = disk_flush, | |
811 | .mark_region = core_mark_region, | |
812 | .clear_region = core_clear_region, | |
813 | .get_resync_work = core_get_resync_work, | |
f3ee6b2f | 814 | .set_region_sync = core_set_region_sync, |
1da177e4 LT |
815 | .get_sync_count = core_get_sync_count, |
816 | .status = disk_status, | |
817 | }; | |
818 | ||
c8da2f8d | 819 | static int __init dm_dirty_log_init(void) |
1da177e4 LT |
820 | { |
821 | int r; | |
822 | ||
416cd17b | 823 | r = dm_dirty_log_type_register(&_core_type); |
1da177e4 LT |
824 | if (r) |
825 | DMWARN("couldn't register core log"); | |
826 | ||
416cd17b | 827 | r = dm_dirty_log_type_register(&_disk_type); |
1da177e4 LT |
828 | if (r) { |
829 | DMWARN("couldn't register disk type"); | |
416cd17b | 830 | dm_dirty_log_type_unregister(&_core_type); |
1da177e4 LT |
831 | } |
832 | ||
833 | return r; | |
834 | } | |
835 | ||
c8da2f8d | 836 | static void __exit dm_dirty_log_exit(void) |
1da177e4 | 837 | { |
416cd17b HM |
838 | dm_dirty_log_type_unregister(&_disk_type); |
839 | dm_dirty_log_type_unregister(&_core_type); | |
1da177e4 LT |
840 | } |
841 | ||
769aef30 HM |
842 | module_init(dm_dirty_log_init); |
843 | module_exit(dm_dirty_log_exit); | |
844 | ||
845 | MODULE_DESCRIPTION(DM_NAME " dirty region log"); | |
846 | MODULE_AUTHOR("Joe Thornber, Heinz Mauelshagen <dm-devel@redhat.com>"); | |
847 | MODULE_LICENSE("GPL"); |