Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2003 Sistina Software Limited. | |
1f965b19 | 3 | * Copyright (C) 2005-2008 Red Hat, Inc. All rights reserved. |
1da177e4 LT |
4 | * |
5 | * This file is released under the GPL. | |
6 | */ | |
7 | ||
06386bbf | 8 | #include "dm-bio-record.h" |
1da177e4 | 9 | |
1da177e4 LT |
10 | #include <linux/init.h> |
11 | #include <linux/mempool.h> | |
12 | #include <linux/module.h> | |
13 | #include <linux/pagemap.h> | |
14 | #include <linux/slab.h> | |
1da177e4 | 15 | #include <linux/workqueue.h> |
1f965b19 | 16 | #include <linux/device-mapper.h> |
a765e20e AK |
17 | #include <linux/dm-io.h> |
18 | #include <linux/dm-dirty-log.h> | |
19 | #include <linux/dm-kcopyd.h> | |
1f965b19 | 20 | #include <linux/dm-region-hash.h> |
1da177e4 | 21 | |
72d94861 | 22 | #define DM_MSG_PREFIX "raid1" |
1f965b19 HM |
23 | |
24 | #define MAX_RECOVERY 1 /* Maximum number of regions recovered in parallel. */ | |
72d94861 | 25 | |
a8e6afa2 | 26 | #define DM_RAID1_HANDLE_ERRORS 0x01 |
f44db678 | 27 | #define errors_handled(p) ((p)->features & DM_RAID1_HANDLE_ERRORS) |
a8e6afa2 | 28 | |
33184048 | 29 | static DECLARE_WAIT_QUEUE_HEAD(_kmirrord_recovery_stopped); |
1da177e4 | 30 | |
e4c8b3ba NB |
31 | /*----------------------------------------------------------------- |
32 | * Mirror set structures. | |
33 | *---------------------------------------------------------------*/ | |
72f4b314 JB |
34 | enum dm_raid1_error { |
35 | DM_RAID1_WRITE_ERROR, | |
64b30c46 | 36 | DM_RAID1_FLUSH_ERROR, |
72f4b314 JB |
37 | DM_RAID1_SYNC_ERROR, |
38 | DM_RAID1_READ_ERROR | |
39 | }; | |
40 | ||
e4c8b3ba | 41 | struct mirror { |
aa5617c5 | 42 | struct mirror_set *ms; |
e4c8b3ba | 43 | atomic_t error_count; |
39ed7adb | 44 | unsigned long error_type; |
e4c8b3ba NB |
45 | struct dm_dev *dev; |
46 | sector_t offset; | |
47 | }; | |
48 | ||
49 | struct mirror_set { | |
50 | struct dm_target *ti; | |
51 | struct list_head list; | |
1f965b19 | 52 | |
a8e6afa2 | 53 | uint64_t features; |
e4c8b3ba | 54 | |
72f4b314 | 55 | spinlock_t lock; /* protects the lists */ |
e4c8b3ba NB |
56 | struct bio_list reads; |
57 | struct bio_list writes; | |
72f4b314 | 58 | struct bio_list failures; |
04788507 | 59 | struct bio_list holds; /* bios are waiting until suspend */ |
e4c8b3ba | 60 | |
1f965b19 HM |
61 | struct dm_region_hash *rh; |
62 | struct dm_kcopyd_client *kcopyd_client; | |
88be163a MB |
63 | struct dm_io_client *io_client; |
64 | ||
e4c8b3ba NB |
65 | /* recovery */ |
66 | region_t nr_regions; | |
67 | int in_sync; | |
fc1ff958 | 68 | int log_failure; |
929be8fc | 69 | int leg_failure; |
b80aa7a0 | 70 | atomic_t suspend; |
e4c8b3ba | 71 | |
72f4b314 | 72 | atomic_t default_mirror; /* Default mirror */ |
e4c8b3ba | 73 | |
6ad36fe2 HS |
74 | struct workqueue_struct *kmirrord_wq; |
75 | struct work_struct kmirrord_work; | |
a2aebe03 MP |
76 | struct timer_list timer; |
77 | unsigned long timer_pending; | |
78 | ||
72f4b314 | 79 | struct work_struct trigger_event; |
6ad36fe2 | 80 | |
1f965b19 | 81 | unsigned nr_mirrors; |
e4c8b3ba NB |
82 | struct mirror mirror[0]; |
83 | }; | |
84 | ||
1f965b19 | 85 | static void wakeup_mirrord(void *context) |
1da177e4 | 86 | { |
1f965b19 | 87 | struct mirror_set *ms = context; |
1da177e4 | 88 | |
6ad36fe2 HS |
89 | queue_work(ms->kmirrord_wq, &ms->kmirrord_work); |
90 | } | |
91 | ||
a2aebe03 MP |
92 | static void delayed_wake_fn(unsigned long data) |
93 | { | |
94 | struct mirror_set *ms = (struct mirror_set *) data; | |
95 | ||
96 | clear_bit(0, &ms->timer_pending); | |
1f965b19 | 97 | wakeup_mirrord(ms); |
a2aebe03 MP |
98 | } |
99 | ||
100 | static void delayed_wake(struct mirror_set *ms) | |
101 | { | |
102 | if (test_and_set_bit(0, &ms->timer_pending)) | |
103 | return; | |
104 | ||
105 | ms->timer.expires = jiffies + HZ / 5; | |
106 | ms->timer.data = (unsigned long) ms; | |
107 | ms->timer.function = delayed_wake_fn; | |
108 | add_timer(&ms->timer); | |
109 | } | |
110 | ||
1f965b19 | 111 | static void wakeup_all_recovery_waiters(void *context) |
1da177e4 | 112 | { |
1f965b19 | 113 | wake_up_all(&_kmirrord_recovery_stopped); |
1da177e4 LT |
114 | } |
115 | ||
1f965b19 | 116 | static void queue_bio(struct mirror_set *ms, struct bio *bio, int rw) |
1da177e4 LT |
117 | { |
118 | unsigned long flags; | |
1da177e4 | 119 | int should_wake = 0; |
1f965b19 | 120 | struct bio_list *bl; |
1da177e4 | 121 | |
1f965b19 HM |
122 | bl = (rw == WRITE) ? &ms->writes : &ms->reads; |
123 | spin_lock_irqsave(&ms->lock, flags); | |
124 | should_wake = !(bl->head); | |
125 | bio_list_add(bl, bio); | |
126 | spin_unlock_irqrestore(&ms->lock, flags); | |
1da177e4 LT |
127 | |
128 | if (should_wake) | |
1f965b19 | 129 | wakeup_mirrord(ms); |
1da177e4 LT |
130 | } |
131 | ||
1f965b19 | 132 | static void dispatch_bios(void *context, struct bio_list *bio_list) |
1da177e4 | 133 | { |
1f965b19 HM |
134 | struct mirror_set *ms = context; |
135 | struct bio *bio; | |
1da177e4 | 136 | |
1f965b19 HM |
137 | while ((bio = bio_list_pop(bio_list))) |
138 | queue_bio(ms, bio, WRITE); | |
1da177e4 LT |
139 | } |
140 | ||
89c7cd89 | 141 | struct dm_raid1_bio_record { |
06386bbf | 142 | struct mirror *m; |
0045d61b | 143 | /* if details->bi_bdev == NULL, details were not saved */ |
06386bbf | 144 | struct dm_bio_details details; |
0045d61b | 145 | region_t write_region; |
06386bbf JB |
146 | }; |
147 | ||
1da177e4 LT |
148 | /* |
149 | * Every mirror should look like this one. | |
150 | */ | |
151 | #define DEFAULT_MIRROR 0 | |
152 | ||
153 | /* | |
06386bbf JB |
154 | * This is yucky. We squirrel the mirror struct away inside |
155 | * bi_next for read/write buffers. This is safe since the bh | |
1da177e4 LT |
156 | * doesn't get submitted to the lower levels of block layer. |
157 | */ | |
06386bbf | 158 | static struct mirror *bio_get_m(struct bio *bio) |
1da177e4 | 159 | { |
06386bbf | 160 | return (struct mirror *) bio->bi_next; |
1da177e4 LT |
161 | } |
162 | ||
06386bbf | 163 | static void bio_set_m(struct bio *bio, struct mirror *m) |
1da177e4 | 164 | { |
06386bbf | 165 | bio->bi_next = (struct bio *) m; |
1da177e4 LT |
166 | } |
167 | ||
72f4b314 JB |
168 | static struct mirror *get_default_mirror(struct mirror_set *ms) |
169 | { | |
170 | return &ms->mirror[atomic_read(&ms->default_mirror)]; | |
171 | } | |
172 | ||
173 | static void set_default_mirror(struct mirror *m) | |
174 | { | |
175 | struct mirror_set *ms = m->ms; | |
176 | struct mirror *m0 = &(ms->mirror[0]); | |
177 | ||
178 | atomic_set(&ms->default_mirror, m - m0); | |
179 | } | |
180 | ||
87968ddd MP |
181 | static struct mirror *get_valid_mirror(struct mirror_set *ms) |
182 | { | |
183 | struct mirror *m; | |
184 | ||
185 | for (m = ms->mirror; m < ms->mirror + ms->nr_mirrors; m++) | |
186 | if (!atomic_read(&m->error_count)) | |
187 | return m; | |
188 | ||
189 | return NULL; | |
190 | } | |
191 | ||
72f4b314 JB |
192 | /* fail_mirror |
193 | * @m: mirror device to fail | |
194 | * @error_type: one of the enum's, DM_RAID1_*_ERROR | |
195 | * | |
196 | * If errors are being handled, record the type of | |
197 | * error encountered for this device. If this type | |
198 | * of error has already been recorded, we can return; | |
199 | * otherwise, we must signal userspace by triggering | |
200 | * an event. Additionally, if the device is the | |
201 | * primary device, we must choose a new primary, but | |
202 | * only if the mirror is in-sync. | |
203 | * | |
204 | * This function must not block. | |
205 | */ | |
206 | static void fail_mirror(struct mirror *m, enum dm_raid1_error error_type) | |
207 | { | |
208 | struct mirror_set *ms = m->ms; | |
209 | struct mirror *new; | |
210 | ||
929be8fc MP |
211 | ms->leg_failure = 1; |
212 | ||
72f4b314 JB |
213 | /* |
214 | * error_count is used for nothing more than a | |
215 | * simple way to tell if a device has encountered | |
216 | * errors. | |
217 | */ | |
218 | atomic_inc(&m->error_count); | |
219 | ||
220 | if (test_and_set_bit(error_type, &m->error_type)) | |
221 | return; | |
222 | ||
d460c65a JB |
223 | if (!errors_handled(ms)) |
224 | return; | |
225 | ||
72f4b314 JB |
226 | if (m != get_default_mirror(ms)) |
227 | goto out; | |
228 | ||
229 | if (!ms->in_sync) { | |
230 | /* | |
231 | * Better to issue requests to same failing device | |
232 | * than to risk returning corrupt data. | |
233 | */ | |
234 | DMERR("Primary mirror (%s) failed while out-of-sync: " | |
235 | "Reads may fail.", m->dev->name); | |
236 | goto out; | |
237 | } | |
238 | ||
87968ddd MP |
239 | new = get_valid_mirror(ms); |
240 | if (new) | |
241 | set_default_mirror(new); | |
242 | else | |
72f4b314 JB |
243 | DMWARN("All sides of mirror have failed."); |
244 | ||
245 | out: | |
246 | schedule_work(&ms->trigger_event); | |
247 | } | |
248 | ||
c0da3748 MP |
249 | static int mirror_flush(struct dm_target *ti) |
250 | { | |
251 | struct mirror_set *ms = ti->private; | |
252 | unsigned long error_bits; | |
253 | ||
254 | unsigned int i; | |
255 | struct dm_io_region io[ms->nr_mirrors]; | |
256 | struct mirror *m; | |
257 | struct dm_io_request io_req = { | |
d87f4c14 | 258 | .bi_rw = WRITE_FLUSH, |
c0da3748 | 259 | .mem.type = DM_IO_KMEM, |
5fc2ffea | 260 | .mem.ptr.addr = NULL, |
c0da3748 MP |
261 | .client = ms->io_client, |
262 | }; | |
263 | ||
264 | for (i = 0, m = ms->mirror; i < ms->nr_mirrors; i++, m++) { | |
265 | io[i].bdev = m->dev->bdev; | |
266 | io[i].sector = 0; | |
267 | io[i].count = 0; | |
268 | } | |
269 | ||
270 | error_bits = -1; | |
271 | dm_io(&io_req, ms->nr_mirrors, io, &error_bits); | |
272 | if (unlikely(error_bits != 0)) { | |
273 | for (i = 0; i < ms->nr_mirrors; i++) | |
274 | if (test_bit(i, &error_bits)) | |
275 | fail_mirror(ms->mirror + i, | |
64b30c46 | 276 | DM_RAID1_FLUSH_ERROR); |
c0da3748 MP |
277 | return -EIO; |
278 | } | |
279 | ||
280 | return 0; | |
281 | } | |
282 | ||
1da177e4 LT |
283 | /*----------------------------------------------------------------- |
284 | * Recovery. | |
285 | * | |
286 | * When a mirror is first activated we may find that some regions | |
287 | * are in the no-sync state. We have to recover these by | |
288 | * recopying from the default mirror to all the others. | |
289 | *---------------------------------------------------------------*/ | |
4cdc1d1f | 290 | static void recovery_complete(int read_err, unsigned long write_err, |
1da177e4 LT |
291 | void *context) |
292 | { | |
1f965b19 HM |
293 | struct dm_region *reg = context; |
294 | struct mirror_set *ms = dm_rh_region_context(reg); | |
8f0205b7 | 295 | int m, bit = 0; |
1da177e4 | 296 | |
8f0205b7 | 297 | if (read_err) { |
f44db678 JB |
298 | /* Read error means the failure of default mirror. */ |
299 | DMERR_LIMIT("Unable to read primary mirror during recovery"); | |
8f0205b7 JB |
300 | fail_mirror(get_default_mirror(ms), DM_RAID1_SYNC_ERROR); |
301 | } | |
f44db678 | 302 | |
8f0205b7 | 303 | if (write_err) { |
4cdc1d1f | 304 | DMERR_LIMIT("Write error during recovery (error = 0x%lx)", |
f44db678 | 305 | write_err); |
8f0205b7 JB |
306 | /* |
307 | * Bits correspond to devices (excluding default mirror). | |
308 | * The default mirror cannot change during recovery. | |
309 | */ | |
310 | for (m = 0; m < ms->nr_mirrors; m++) { | |
311 | if (&ms->mirror[m] == get_default_mirror(ms)) | |
312 | continue; | |
313 | if (test_bit(bit, &write_err)) | |
314 | fail_mirror(ms->mirror + m, | |
315 | DM_RAID1_SYNC_ERROR); | |
316 | bit++; | |
317 | } | |
318 | } | |
f44db678 | 319 | |
1f965b19 | 320 | dm_rh_recovery_end(reg, !(read_err || write_err)); |
1da177e4 LT |
321 | } |
322 | ||
1f965b19 | 323 | static int recover(struct mirror_set *ms, struct dm_region *reg) |
1da177e4 LT |
324 | { |
325 | int r; | |
1f965b19 | 326 | unsigned i; |
eb69aca5 | 327 | struct dm_io_region from, to[DM_KCOPYD_MAX_REGIONS], *dest; |
1da177e4 LT |
328 | struct mirror *m; |
329 | unsigned long flags = 0; | |
1f965b19 HM |
330 | region_t key = dm_rh_get_region_key(reg); |
331 | sector_t region_size = dm_rh_get_region_size(ms->rh); | |
1da177e4 LT |
332 | |
333 | /* fill in the source */ | |
72f4b314 | 334 | m = get_default_mirror(ms); |
1da177e4 | 335 | from.bdev = m->dev->bdev; |
1f965b19 HM |
336 | from.sector = m->offset + dm_rh_region_to_sector(ms->rh, key); |
337 | if (key == (ms->nr_regions - 1)) { | |
1da177e4 LT |
338 | /* |
339 | * The final region may be smaller than | |
340 | * region_size. | |
341 | */ | |
1f965b19 | 342 | from.count = ms->ti->len & (region_size - 1); |
1da177e4 | 343 | if (!from.count) |
1f965b19 | 344 | from.count = region_size; |
1da177e4 | 345 | } else |
1f965b19 | 346 | from.count = region_size; |
1da177e4 LT |
347 | |
348 | /* fill in the destinations */ | |
349 | for (i = 0, dest = to; i < ms->nr_mirrors; i++) { | |
72f4b314 | 350 | if (&ms->mirror[i] == get_default_mirror(ms)) |
1da177e4 LT |
351 | continue; |
352 | ||
353 | m = ms->mirror + i; | |
354 | dest->bdev = m->dev->bdev; | |
1f965b19 | 355 | dest->sector = m->offset + dm_rh_region_to_sector(ms->rh, key); |
1da177e4 LT |
356 | dest->count = from.count; |
357 | dest++; | |
358 | } | |
359 | ||
360 | /* hand to kcopyd */ | |
f7c83e2e JB |
361 | if (!errors_handled(ms)) |
362 | set_bit(DM_KCOPYD_IGNORE_ERROR, &flags); | |
363 | ||
eb69aca5 HM |
364 | r = dm_kcopyd_copy(ms->kcopyd_client, &from, ms->nr_mirrors - 1, to, |
365 | flags, recovery_complete, reg); | |
1da177e4 LT |
366 | |
367 | return r; | |
368 | } | |
369 | ||
370 | static void do_recovery(struct mirror_set *ms) | |
371 | { | |
1f965b19 HM |
372 | struct dm_region *reg; |
373 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); | |
1da177e4 | 374 | int r; |
1da177e4 LT |
375 | |
376 | /* | |
377 | * Start quiescing some regions. | |
378 | */ | |
1f965b19 | 379 | dm_rh_recovery_prepare(ms->rh); |
1da177e4 LT |
380 | |
381 | /* | |
382 | * Copy any already quiesced regions. | |
383 | */ | |
1f965b19 | 384 | while ((reg = dm_rh_recovery_start(ms->rh))) { |
1da177e4 LT |
385 | r = recover(ms, reg); |
386 | if (r) | |
1f965b19 | 387 | dm_rh_recovery_end(reg, 0); |
1da177e4 LT |
388 | } |
389 | ||
390 | /* | |
391 | * Update the in sync flag. | |
392 | */ | |
393 | if (!ms->in_sync && | |
394 | (log->type->get_sync_count(log) == ms->nr_regions)) { | |
395 | /* the sync is complete */ | |
396 | dm_table_event(ms->ti->table); | |
397 | ms->in_sync = 1; | |
398 | } | |
399 | } | |
400 | ||
401 | /*----------------------------------------------------------------- | |
402 | * Reads | |
403 | *---------------------------------------------------------------*/ | |
404 | static struct mirror *choose_mirror(struct mirror_set *ms, sector_t sector) | |
405 | { | |
06386bbf JB |
406 | struct mirror *m = get_default_mirror(ms); |
407 | ||
408 | do { | |
409 | if (likely(!atomic_read(&m->error_count))) | |
410 | return m; | |
411 | ||
412 | if (m-- == ms->mirror) | |
413 | m += ms->nr_mirrors; | |
414 | } while (m != get_default_mirror(ms)); | |
415 | ||
416 | return NULL; | |
417 | } | |
418 | ||
419 | static int default_ok(struct mirror *m) | |
420 | { | |
421 | struct mirror *default_mirror = get_default_mirror(m->ms); | |
422 | ||
423 | return !atomic_read(&default_mirror->error_count); | |
424 | } | |
425 | ||
426 | static int mirror_available(struct mirror_set *ms, struct bio *bio) | |
427 | { | |
1f965b19 HM |
428 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
429 | region_t region = dm_rh_bio_to_region(ms->rh, bio); | |
06386bbf | 430 | |
1f965b19 | 431 | if (log->type->in_sync(log, region, 0)) |
06386bbf JB |
432 | return choose_mirror(ms, bio->bi_sector) ? 1 : 0; |
433 | ||
434 | return 0; | |
1da177e4 LT |
435 | } |
436 | ||
437 | /* | |
438 | * remap a buffer to a particular mirror. | |
439 | */ | |
06386bbf JB |
440 | static sector_t map_sector(struct mirror *m, struct bio *bio) |
441 | { | |
4184153f MP |
442 | if (unlikely(!bio->bi_size)) |
443 | return 0; | |
b441a262 | 444 | return m->offset + dm_target_offset(m->ms->ti, bio->bi_sector); |
06386bbf JB |
445 | } |
446 | ||
447 | static void map_bio(struct mirror *m, struct bio *bio) | |
1da177e4 LT |
448 | { |
449 | bio->bi_bdev = m->dev->bdev; | |
06386bbf JB |
450 | bio->bi_sector = map_sector(m, bio); |
451 | } | |
452 | ||
22a1ceb1 | 453 | static void map_region(struct dm_io_region *io, struct mirror *m, |
06386bbf JB |
454 | struct bio *bio) |
455 | { | |
456 | io->bdev = m->dev->bdev; | |
457 | io->sector = map_sector(m, bio); | |
458 | io->count = bio->bi_size >> 9; | |
459 | } | |
460 | ||
04788507 MP |
461 | static void hold_bio(struct mirror_set *ms, struct bio *bio) |
462 | { | |
463 | /* | |
f0703040 TY |
464 | * Lock is required to avoid race condition during suspend |
465 | * process. | |
04788507 | 466 | */ |
f0703040 TY |
467 | spin_lock_irq(&ms->lock); |
468 | ||
04788507 | 469 | if (atomic_read(&ms->suspend)) { |
f0703040 TY |
470 | spin_unlock_irq(&ms->lock); |
471 | ||
472 | /* | |
473 | * If device is suspended, complete the bio. | |
474 | */ | |
04788507 MP |
475 | if (dm_noflush_suspending(ms->ti)) |
476 | bio_endio(bio, DM_ENDIO_REQUEUE); | |
477 | else | |
478 | bio_endio(bio, -EIO); | |
479 | return; | |
480 | } | |
481 | ||
482 | /* | |
483 | * Hold bio until the suspend is complete. | |
484 | */ | |
04788507 MP |
485 | bio_list_add(&ms->holds, bio); |
486 | spin_unlock_irq(&ms->lock); | |
487 | } | |
488 | ||
06386bbf JB |
489 | /*----------------------------------------------------------------- |
490 | * Reads | |
491 | *---------------------------------------------------------------*/ | |
492 | static void read_callback(unsigned long error, void *context) | |
493 | { | |
494 | struct bio *bio = context; | |
495 | struct mirror *m; | |
496 | ||
497 | m = bio_get_m(bio); | |
498 | bio_set_m(bio, NULL); | |
499 | ||
500 | if (likely(!error)) { | |
501 | bio_endio(bio, 0); | |
502 | return; | |
503 | } | |
504 | ||
505 | fail_mirror(m, DM_RAID1_READ_ERROR); | |
506 | ||
507 | if (likely(default_ok(m)) || mirror_available(m->ms, bio)) { | |
508 | DMWARN_LIMIT("Read failure on mirror device %s. " | |
509 | "Trying alternative device.", | |
510 | m->dev->name); | |
511 | queue_bio(m->ms, bio, bio_rw(bio)); | |
512 | return; | |
513 | } | |
514 | ||
515 | DMERR_LIMIT("Read failure on mirror device %s. Failing I/O.", | |
516 | m->dev->name); | |
517 | bio_endio(bio, -EIO); | |
518 | } | |
519 | ||
520 | /* Asynchronous read. */ | |
521 | static void read_async_bio(struct mirror *m, struct bio *bio) | |
522 | { | |
22a1ceb1 | 523 | struct dm_io_region io; |
06386bbf JB |
524 | struct dm_io_request io_req = { |
525 | .bi_rw = READ, | |
526 | .mem.type = DM_IO_BVEC, | |
527 | .mem.ptr.bvec = bio->bi_io_vec + bio->bi_idx, | |
528 | .notify.fn = read_callback, | |
529 | .notify.context = bio, | |
530 | .client = m->ms->io_client, | |
531 | }; | |
532 | ||
533 | map_region(&io, m, bio); | |
534 | bio_set_m(bio, m); | |
1f965b19 HM |
535 | BUG_ON(dm_io(&io_req, 1, &io, NULL)); |
536 | } | |
537 | ||
538 | static inline int region_in_sync(struct mirror_set *ms, region_t region, | |
539 | int may_block) | |
540 | { | |
541 | int state = dm_rh_get_state(ms->rh, region, may_block); | |
542 | return state == DM_RH_CLEAN || state == DM_RH_DIRTY; | |
1da177e4 LT |
543 | } |
544 | ||
545 | static void do_reads(struct mirror_set *ms, struct bio_list *reads) | |
546 | { | |
547 | region_t region; | |
548 | struct bio *bio; | |
549 | struct mirror *m; | |
550 | ||
551 | while ((bio = bio_list_pop(reads))) { | |
1f965b19 | 552 | region = dm_rh_bio_to_region(ms->rh, bio); |
06386bbf | 553 | m = get_default_mirror(ms); |
1da177e4 LT |
554 | |
555 | /* | |
556 | * We can only read balance if the region is in sync. | |
557 | */ | |
1f965b19 | 558 | if (likely(region_in_sync(ms, region, 1))) |
1da177e4 | 559 | m = choose_mirror(ms, bio->bi_sector); |
06386bbf JB |
560 | else if (m && atomic_read(&m->error_count)) |
561 | m = NULL; | |
1da177e4 | 562 | |
06386bbf JB |
563 | if (likely(m)) |
564 | read_async_bio(m, bio); | |
565 | else | |
566 | bio_endio(bio, -EIO); | |
1da177e4 LT |
567 | } |
568 | } | |
569 | ||
570 | /*----------------------------------------------------------------- | |
571 | * Writes. | |
572 | * | |
573 | * We do different things with the write io depending on the | |
574 | * state of the region that it's in: | |
575 | * | |
576 | * SYNC: increment pending, use kcopyd to write to *all* mirrors | |
577 | * RECOVERING: delay the io until recovery completes | |
578 | * NOSYNC: increment pending, just write to the default mirror | |
579 | *---------------------------------------------------------------*/ | |
72f4b314 | 580 | |
72f4b314 | 581 | |
1da177e4 LT |
582 | static void write_callback(unsigned long error, void *context) |
583 | { | |
72f4b314 | 584 | unsigned i, ret = 0; |
1da177e4 LT |
585 | struct bio *bio = (struct bio *) context; |
586 | struct mirror_set *ms; | |
72f4b314 JB |
587 | int should_wake = 0; |
588 | unsigned long flags; | |
1da177e4 | 589 | |
06386bbf JB |
590 | ms = bio_get_m(bio)->ms; |
591 | bio_set_m(bio, NULL); | |
1da177e4 LT |
592 | |
593 | /* | |
594 | * NOTE: We don't decrement the pending count here, | |
595 | * instead it is done by the targets endio function. | |
596 | * This way we handle both writes to SYNC and NOSYNC | |
597 | * regions with the same code. | |
598 | */ | |
60f355ea MP |
599 | if (likely(!error)) { |
600 | bio_endio(bio, ret); | |
601 | return; | |
602 | } | |
1da177e4 | 603 | |
72f4b314 JB |
604 | for (i = 0; i < ms->nr_mirrors; i++) |
605 | if (test_bit(i, &error)) | |
606 | fail_mirror(ms->mirror + i, DM_RAID1_WRITE_ERROR); | |
72f4b314 | 607 | |
60f355ea MP |
608 | /* |
609 | * Need to raise event. Since raising | |
610 | * events can block, we need to do it in | |
611 | * the main thread. | |
612 | */ | |
613 | spin_lock_irqsave(&ms->lock, flags); | |
614 | if (!ms->failures.head) | |
615 | should_wake = 1; | |
616 | bio_list_add(&ms->failures, bio); | |
617 | spin_unlock_irqrestore(&ms->lock, flags); | |
618 | if (should_wake) | |
619 | wakeup_mirrord(ms); | |
1da177e4 LT |
620 | } |
621 | ||
622 | static void do_write(struct mirror_set *ms, struct bio *bio) | |
623 | { | |
624 | unsigned int i; | |
22a1ceb1 | 625 | struct dm_io_region io[ms->nr_mirrors], *dest = io; |
1da177e4 | 626 | struct mirror *m; |
88be163a | 627 | struct dm_io_request io_req = { |
d87f4c14 | 628 | .bi_rw = WRITE | (bio->bi_rw & WRITE_FLUSH_FUA), |
88be163a MB |
629 | .mem.type = DM_IO_BVEC, |
630 | .mem.ptr.bvec = bio->bi_io_vec + bio->bi_idx, | |
631 | .notify.fn = write_callback, | |
632 | .notify.context = bio, | |
633 | .client = ms->io_client, | |
634 | }; | |
1da177e4 | 635 | |
5fc2ffea MS |
636 | if (bio->bi_rw & REQ_DISCARD) { |
637 | io_req.bi_rw |= REQ_DISCARD; | |
638 | io_req.mem.type = DM_IO_KMEM; | |
639 | io_req.mem.ptr.addr = NULL; | |
640 | } | |
641 | ||
06386bbf JB |
642 | for (i = 0, m = ms->mirror; i < ms->nr_mirrors; i++, m++) |
643 | map_region(dest++, m, bio); | |
1da177e4 | 644 | |
06386bbf JB |
645 | /* |
646 | * Use default mirror because we only need it to retrieve the reference | |
647 | * to the mirror set in write_callback(). | |
648 | */ | |
649 | bio_set_m(bio, get_default_mirror(ms)); | |
88be163a | 650 | |
1f965b19 | 651 | BUG_ON(dm_io(&io_req, ms->nr_mirrors, io, NULL)); |
1da177e4 LT |
652 | } |
653 | ||
654 | static void do_writes(struct mirror_set *ms, struct bio_list *writes) | |
655 | { | |
656 | int state; | |
657 | struct bio *bio; | |
658 | struct bio_list sync, nosync, recover, *this_list = NULL; | |
7513c2a7 JB |
659 | struct bio_list requeue; |
660 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); | |
661 | region_t region; | |
1da177e4 LT |
662 | |
663 | if (!writes->head) | |
664 | return; | |
665 | ||
666 | /* | |
667 | * Classify each write. | |
668 | */ | |
669 | bio_list_init(&sync); | |
670 | bio_list_init(&nosync); | |
671 | bio_list_init(&recover); | |
7513c2a7 | 672 | bio_list_init(&requeue); |
1da177e4 LT |
673 | |
674 | while ((bio = bio_list_pop(writes))) { | |
5fc2ffea MS |
675 | if ((bio->bi_rw & REQ_FLUSH) || |
676 | (bio->bi_rw & REQ_DISCARD)) { | |
4184153f MP |
677 | bio_list_add(&sync, bio); |
678 | continue; | |
679 | } | |
680 | ||
7513c2a7 JB |
681 | region = dm_rh_bio_to_region(ms->rh, bio); |
682 | ||
683 | if (log->type->is_remote_recovering && | |
684 | log->type->is_remote_recovering(log, region)) { | |
685 | bio_list_add(&requeue, bio); | |
686 | continue; | |
687 | } | |
688 | ||
689 | state = dm_rh_get_state(ms->rh, region, 1); | |
1da177e4 | 690 | switch (state) { |
1f965b19 HM |
691 | case DM_RH_CLEAN: |
692 | case DM_RH_DIRTY: | |
1da177e4 LT |
693 | this_list = &sync; |
694 | break; | |
695 | ||
1f965b19 | 696 | case DM_RH_NOSYNC: |
1da177e4 LT |
697 | this_list = &nosync; |
698 | break; | |
699 | ||
1f965b19 | 700 | case DM_RH_RECOVERING: |
1da177e4 LT |
701 | this_list = &recover; |
702 | break; | |
703 | } | |
704 | ||
705 | bio_list_add(this_list, bio); | |
706 | } | |
707 | ||
7513c2a7 JB |
708 | /* |
709 | * Add bios that are delayed due to remote recovery | |
710 | * back on to the write queue | |
711 | */ | |
712 | if (unlikely(requeue.head)) { | |
713 | spin_lock_irq(&ms->lock); | |
714 | bio_list_merge(&ms->writes, &requeue); | |
715 | spin_unlock_irq(&ms->lock); | |
69885683 | 716 | delayed_wake(ms); |
7513c2a7 JB |
717 | } |
718 | ||
1da177e4 LT |
719 | /* |
720 | * Increment the pending counts for any regions that will | |
721 | * be written to (writes to recover regions are going to | |
722 | * be delayed). | |
723 | */ | |
1f965b19 HM |
724 | dm_rh_inc_pending(ms->rh, &sync); |
725 | dm_rh_inc_pending(ms->rh, &nosync); | |
d2b69864 JB |
726 | |
727 | /* | |
728 | * If the flush fails on a previous call and succeeds here, | |
729 | * we must not reset the log_failure variable. We need | |
730 | * userspace interaction to do that. | |
731 | */ | |
732 | ms->log_failure = dm_rh_flush(ms->rh) ? 1 : ms->log_failure; | |
1da177e4 LT |
733 | |
734 | /* | |
735 | * Dispatch io. | |
736 | */ | |
5528d17d | 737 | if (unlikely(ms->log_failure) && errors_handled(ms)) { |
b80aa7a0 JB |
738 | spin_lock_irq(&ms->lock); |
739 | bio_list_merge(&ms->failures, &sync); | |
740 | spin_unlock_irq(&ms->lock); | |
1f965b19 | 741 | wakeup_mirrord(ms); |
b80aa7a0 | 742 | } else |
fc1ff958 | 743 | while ((bio = bio_list_pop(&sync))) |
b80aa7a0 | 744 | do_write(ms, bio); |
1da177e4 LT |
745 | |
746 | while ((bio = bio_list_pop(&recover))) | |
1f965b19 | 747 | dm_rh_delay(ms->rh, bio); |
1da177e4 LT |
748 | |
749 | while ((bio = bio_list_pop(&nosync))) { | |
ede5ea0b MP |
750 | if (unlikely(ms->leg_failure) && errors_handled(ms)) { |
751 | spin_lock_irq(&ms->lock); | |
752 | bio_list_add(&ms->failures, bio); | |
753 | spin_unlock_irq(&ms->lock); | |
754 | wakeup_mirrord(ms); | |
755 | } else { | |
929be8fc MP |
756 | map_bio(get_default_mirror(ms), bio); |
757 | generic_make_request(bio); | |
758 | } | |
1da177e4 LT |
759 | } |
760 | } | |
761 | ||
72f4b314 JB |
762 | static void do_failures(struct mirror_set *ms, struct bio_list *failures) |
763 | { | |
764 | struct bio *bio; | |
765 | ||
0f398a84 | 766 | if (likely(!failures->head)) |
72f4b314 JB |
767 | return; |
768 | ||
b80aa7a0 JB |
769 | /* |
770 | * If the log has failed, unattempted writes are being | |
0f398a84 | 771 | * put on the holds list. We can't issue those writes |
b80aa7a0 JB |
772 | * until a log has been marked, so we must store them. |
773 | * | |
774 | * If a 'noflush' suspend is in progress, we can requeue | |
775 | * the I/O's to the core. This give userspace a chance | |
776 | * to reconfigure the mirror, at which point the core | |
777 | * will reissue the writes. If the 'noflush' flag is | |
778 | * not set, we have no choice but to return errors. | |
779 | * | |
780 | * Some writes on the failures list may have been | |
781 | * submitted before the log failure and represent a | |
782 | * failure to write to one of the devices. It is ok | |
783 | * for us to treat them the same and requeue them | |
784 | * as well. | |
785 | */ | |
0f398a84 | 786 | while ((bio = bio_list_pop(failures))) { |
60f355ea | 787 | if (!ms->log_failure) { |
0f398a84 | 788 | ms->in_sync = 0; |
c58098be | 789 | dm_rh_mark_nosync(ms->rh, bio); |
0f398a84 | 790 | } |
60f355ea MP |
791 | |
792 | /* | |
793 | * If all the legs are dead, fail the I/O. | |
794 | * If we have been told to handle errors, hold the bio | |
795 | * and wait for userspace to deal with the problem. | |
796 | * Otherwise pretend that the I/O succeeded. (This would | |
797 | * be wrong if the failed leg returned after reboot and | |
798 | * got replicated back to the good legs.) | |
799 | */ | |
800 | if (!get_valid_mirror(ms)) | |
801 | bio_endio(bio, -EIO); | |
802 | else if (errors_handled(ms)) | |
803 | hold_bio(ms, bio); | |
804 | else | |
805 | bio_endio(bio, 0); | |
b80aa7a0 | 806 | } |
72f4b314 JB |
807 | } |
808 | ||
809 | static void trigger_event(struct work_struct *work) | |
810 | { | |
811 | struct mirror_set *ms = | |
812 | container_of(work, struct mirror_set, trigger_event); | |
813 | ||
814 | dm_table_event(ms->ti->table); | |
815 | } | |
816 | ||
1da177e4 LT |
817 | /*----------------------------------------------------------------- |
818 | * kmirrord | |
819 | *---------------------------------------------------------------*/ | |
a2aebe03 | 820 | static void do_mirror(struct work_struct *work) |
1da177e4 | 821 | { |
1f965b19 HM |
822 | struct mirror_set *ms = container_of(work, struct mirror_set, |
823 | kmirrord_work); | |
72f4b314 JB |
824 | struct bio_list reads, writes, failures; |
825 | unsigned long flags; | |
1da177e4 | 826 | |
72f4b314 | 827 | spin_lock_irqsave(&ms->lock, flags); |
1da177e4 LT |
828 | reads = ms->reads; |
829 | writes = ms->writes; | |
72f4b314 | 830 | failures = ms->failures; |
1da177e4 LT |
831 | bio_list_init(&ms->reads); |
832 | bio_list_init(&ms->writes); | |
72f4b314 JB |
833 | bio_list_init(&ms->failures); |
834 | spin_unlock_irqrestore(&ms->lock, flags); | |
1da177e4 | 835 | |
1f965b19 | 836 | dm_rh_update_states(ms->rh, errors_handled(ms)); |
1da177e4 LT |
837 | do_recovery(ms); |
838 | do_reads(ms, &reads); | |
839 | do_writes(ms, &writes); | |
72f4b314 | 840 | do_failures(ms, &failures); |
1da177e4 LT |
841 | } |
842 | ||
1da177e4 LT |
843 | /*----------------------------------------------------------------- |
844 | * Target functions | |
845 | *---------------------------------------------------------------*/ | |
846 | static struct mirror_set *alloc_context(unsigned int nr_mirrors, | |
847 | uint32_t region_size, | |
848 | struct dm_target *ti, | |
416cd17b | 849 | struct dm_dirty_log *dl) |
1da177e4 LT |
850 | { |
851 | size_t len; | |
852 | struct mirror_set *ms = NULL; | |
853 | ||
1da177e4 LT |
854 | len = sizeof(*ms) + (sizeof(ms->mirror[0]) * nr_mirrors); |
855 | ||
dd00cc48 | 856 | ms = kzalloc(len, GFP_KERNEL); |
1da177e4 | 857 | if (!ms) { |
72d94861 | 858 | ti->error = "Cannot allocate mirror context"; |
1da177e4 LT |
859 | return NULL; |
860 | } | |
861 | ||
1da177e4 | 862 | spin_lock_init(&ms->lock); |
5339fc2d MP |
863 | bio_list_init(&ms->reads); |
864 | bio_list_init(&ms->writes); | |
865 | bio_list_init(&ms->failures); | |
866 | bio_list_init(&ms->holds); | |
1da177e4 LT |
867 | |
868 | ms->ti = ti; | |
869 | ms->nr_mirrors = nr_mirrors; | |
870 | ms->nr_regions = dm_sector_div_up(ti->len, region_size); | |
871 | ms->in_sync = 0; | |
b80aa7a0 | 872 | ms->log_failure = 0; |
929be8fc | 873 | ms->leg_failure = 0; |
b80aa7a0 | 874 | atomic_set(&ms->suspend, 0); |
72f4b314 | 875 | atomic_set(&ms->default_mirror, DEFAULT_MIRROR); |
1da177e4 | 876 | |
bda8efec | 877 | ms->io_client = dm_io_client_create(); |
88be163a MB |
878 | if (IS_ERR(ms->io_client)) { |
879 | ti->error = "Error creating dm_io client"; | |
880 | kfree(ms); | |
881 | return NULL; | |
882 | } | |
883 | ||
1f965b19 HM |
884 | ms->rh = dm_region_hash_create(ms, dispatch_bios, wakeup_mirrord, |
885 | wakeup_all_recovery_waiters, | |
886 | ms->ti->begin, MAX_RECOVERY, | |
887 | dl, region_size, ms->nr_regions); | |
888 | if (IS_ERR(ms->rh)) { | |
72d94861 | 889 | ti->error = "Error creating dirty region hash"; |
a72cf737 | 890 | dm_io_client_destroy(ms->io_client); |
1da177e4 LT |
891 | kfree(ms); |
892 | return NULL; | |
893 | } | |
894 | ||
895 | return ms; | |
896 | } | |
897 | ||
898 | static void free_context(struct mirror_set *ms, struct dm_target *ti, | |
899 | unsigned int m) | |
900 | { | |
901 | while (m--) | |
902 | dm_put_device(ti, ms->mirror[m].dev); | |
903 | ||
88be163a | 904 | dm_io_client_destroy(ms->io_client); |
1f965b19 | 905 | dm_region_hash_destroy(ms->rh); |
1da177e4 LT |
906 | kfree(ms); |
907 | } | |
908 | ||
1da177e4 LT |
909 | static int get_mirror(struct mirror_set *ms, struct dm_target *ti, |
910 | unsigned int mirror, char **argv) | |
911 | { | |
4ee218cd | 912 | unsigned long long offset; |
31998ef1 | 913 | char dummy; |
1da177e4 | 914 | |
31998ef1 | 915 | if (sscanf(argv[1], "%llu%c", &offset, &dummy) != 1) { |
72d94861 | 916 | ti->error = "Invalid offset"; |
1da177e4 LT |
917 | return -EINVAL; |
918 | } | |
919 | ||
8215d6ec | 920 | if (dm_get_device(ti, argv[0], dm_table_get_mode(ti->table), |
1da177e4 | 921 | &ms->mirror[mirror].dev)) { |
72d94861 | 922 | ti->error = "Device lookup failure"; |
1da177e4 LT |
923 | return -ENXIO; |
924 | } | |
925 | ||
aa5617c5 | 926 | ms->mirror[mirror].ms = ms; |
72f4b314 JB |
927 | atomic_set(&(ms->mirror[mirror].error_count), 0); |
928 | ms->mirror[mirror].error_type = 0; | |
1da177e4 LT |
929 | ms->mirror[mirror].offset = offset; |
930 | ||
931 | return 0; | |
932 | } | |
933 | ||
1da177e4 LT |
934 | /* |
935 | * Create dirty log: log_type #log_params <log_params> | |
936 | */ | |
416cd17b | 937 | static struct dm_dirty_log *create_dirty_log(struct dm_target *ti, |
1f965b19 HM |
938 | unsigned argc, char **argv, |
939 | unsigned *args_used) | |
1da177e4 | 940 | { |
1f965b19 | 941 | unsigned param_count; |
416cd17b | 942 | struct dm_dirty_log *dl; |
31998ef1 | 943 | char dummy; |
1da177e4 LT |
944 | |
945 | if (argc < 2) { | |
72d94861 | 946 | ti->error = "Insufficient mirror log arguments"; |
1da177e4 LT |
947 | return NULL; |
948 | } | |
949 | ||
31998ef1 | 950 | if (sscanf(argv[1], "%u%c", ¶m_count, &dummy) != 1) { |
72d94861 | 951 | ti->error = "Invalid mirror log argument count"; |
1da177e4 LT |
952 | return NULL; |
953 | } | |
954 | ||
955 | *args_used = 2 + param_count; | |
956 | ||
957 | if (argc < *args_used) { | |
72d94861 | 958 | ti->error = "Insufficient mirror log arguments"; |
1da177e4 LT |
959 | return NULL; |
960 | } | |
961 | ||
c0da3748 MP |
962 | dl = dm_dirty_log_create(argv[0], ti, mirror_flush, param_count, |
963 | argv + 2); | |
1da177e4 | 964 | if (!dl) { |
72d94861 | 965 | ti->error = "Error creating mirror dirty log"; |
1da177e4 LT |
966 | return NULL; |
967 | } | |
968 | ||
1da177e4 LT |
969 | return dl; |
970 | } | |
971 | ||
a8e6afa2 JB |
972 | static int parse_features(struct mirror_set *ms, unsigned argc, char **argv, |
973 | unsigned *args_used) | |
974 | { | |
975 | unsigned num_features; | |
976 | struct dm_target *ti = ms->ti; | |
31998ef1 | 977 | char dummy; |
a8e6afa2 JB |
978 | |
979 | *args_used = 0; | |
980 | ||
981 | if (!argc) | |
982 | return 0; | |
983 | ||
31998ef1 | 984 | if (sscanf(argv[0], "%u%c", &num_features, &dummy) != 1) { |
a8e6afa2 JB |
985 | ti->error = "Invalid number of features"; |
986 | return -EINVAL; | |
987 | } | |
988 | ||
989 | argc--; | |
990 | argv++; | |
991 | (*args_used)++; | |
992 | ||
993 | if (num_features > argc) { | |
994 | ti->error = "Not enough arguments to support feature count"; | |
995 | return -EINVAL; | |
996 | } | |
997 | ||
998 | if (!strcmp("handle_errors", argv[0])) | |
999 | ms->features |= DM_RAID1_HANDLE_ERRORS; | |
1000 | else { | |
1001 | ti->error = "Unrecognised feature requested"; | |
1002 | return -EINVAL; | |
1003 | } | |
1004 | ||
1005 | (*args_used)++; | |
1006 | ||
1007 | return 0; | |
1008 | } | |
1009 | ||
1da177e4 LT |
1010 | /* |
1011 | * Construct a mirror mapping: | |
1012 | * | |
1013 | * log_type #log_params <log_params> | |
1014 | * #mirrors [mirror_path offset]{2,} | |
a8e6afa2 | 1015 | * [#features <features>] |
1da177e4 LT |
1016 | * |
1017 | * log_type is "core" or "disk" | |
1018 | * #log_params is between 1 and 3 | |
a8e6afa2 JB |
1019 | * |
1020 | * If present, features must be "handle_errors". | |
1da177e4 | 1021 | */ |
1da177e4 LT |
1022 | static int mirror_ctr(struct dm_target *ti, unsigned int argc, char **argv) |
1023 | { | |
1024 | int r; | |
1025 | unsigned int nr_mirrors, m, args_used; | |
1026 | struct mirror_set *ms; | |
416cd17b | 1027 | struct dm_dirty_log *dl; |
31998ef1 | 1028 | char dummy; |
1da177e4 LT |
1029 | |
1030 | dl = create_dirty_log(ti, argc, argv, &args_used); | |
1031 | if (!dl) | |
1032 | return -EINVAL; | |
1033 | ||
1034 | argv += args_used; | |
1035 | argc -= args_used; | |
1036 | ||
31998ef1 | 1037 | if (!argc || sscanf(argv[0], "%u%c", &nr_mirrors, &dummy) != 1 || |
eb69aca5 | 1038 | nr_mirrors < 2 || nr_mirrors > DM_KCOPYD_MAX_REGIONS + 1) { |
72d94861 | 1039 | ti->error = "Invalid number of mirrors"; |
416cd17b | 1040 | dm_dirty_log_destroy(dl); |
1da177e4 LT |
1041 | return -EINVAL; |
1042 | } | |
1043 | ||
1044 | argv++, argc--; | |
1045 | ||
a8e6afa2 JB |
1046 | if (argc < nr_mirrors * 2) { |
1047 | ti->error = "Too few mirror arguments"; | |
416cd17b | 1048 | dm_dirty_log_destroy(dl); |
1da177e4 LT |
1049 | return -EINVAL; |
1050 | } | |
1051 | ||
1052 | ms = alloc_context(nr_mirrors, dl->type->get_region_size(dl), ti, dl); | |
1053 | if (!ms) { | |
416cd17b | 1054 | dm_dirty_log_destroy(dl); |
1da177e4 LT |
1055 | return -ENOMEM; |
1056 | } | |
1057 | ||
1058 | /* Get the mirror parameter sets */ | |
1059 | for (m = 0; m < nr_mirrors; m++) { | |
1060 | r = get_mirror(ms, ti, m, argv); | |
1061 | if (r) { | |
1062 | free_context(ms, ti, m); | |
1063 | return r; | |
1064 | } | |
1065 | argv += 2; | |
1066 | argc -= 2; | |
1067 | } | |
1068 | ||
1069 | ti->private = ms; | |
542f9038 MS |
1070 | |
1071 | r = dm_set_target_max_io_len(ti, dm_rh_get_region_size(ms->rh)); | |
1072 | if (r) | |
1073 | goto err_free_context; | |
1074 | ||
55a62eef AK |
1075 | ti->num_flush_bios = 1; |
1076 | ti->num_discard_bios = 1; | |
89c7cd89 | 1077 | ti->per_bio_data_size = sizeof(struct dm_raid1_bio_record); |
0ac55489 | 1078 | ti->discard_zeroes_data_unsupported = true; |
1da177e4 | 1079 | |
9c4376de TH |
1080 | ms->kmirrord_wq = alloc_workqueue("kmirrord", |
1081 | WQ_NON_REENTRANT | WQ_MEM_RECLAIM, 0); | |
6ad36fe2 HS |
1082 | if (!ms->kmirrord_wq) { |
1083 | DMERR("couldn't start kmirrord"); | |
a72cf737 DM |
1084 | r = -ENOMEM; |
1085 | goto err_free_context; | |
6ad36fe2 HS |
1086 | } |
1087 | INIT_WORK(&ms->kmirrord_work, do_mirror); | |
a2aebe03 MP |
1088 | init_timer(&ms->timer); |
1089 | ms->timer_pending = 0; | |
72f4b314 | 1090 | INIT_WORK(&ms->trigger_event, trigger_event); |
6ad36fe2 | 1091 | |
a8e6afa2 | 1092 | r = parse_features(ms, argc, argv, &args_used); |
a72cf737 DM |
1093 | if (r) |
1094 | goto err_destroy_wq; | |
a8e6afa2 JB |
1095 | |
1096 | argv += args_used; | |
1097 | argc -= args_used; | |
1098 | ||
f44db678 JB |
1099 | /* |
1100 | * Any read-balancing addition depends on the | |
1101 | * DM_RAID1_HANDLE_ERRORS flag being present. | |
1102 | * This is because the decision to balance depends | |
1103 | * on the sync state of a region. If the above | |
1104 | * flag is not present, we ignore errors; and | |
1105 | * the sync state may be inaccurate. | |
1106 | */ | |
1107 | ||
a8e6afa2 JB |
1108 | if (argc) { |
1109 | ti->error = "Too many mirror arguments"; | |
a72cf737 DM |
1110 | r = -EINVAL; |
1111 | goto err_destroy_wq; | |
a8e6afa2 JB |
1112 | } |
1113 | ||
fa34ce73 MP |
1114 | ms->kcopyd_client = dm_kcopyd_client_create(); |
1115 | if (IS_ERR(ms->kcopyd_client)) { | |
1116 | r = PTR_ERR(ms->kcopyd_client); | |
a72cf737 | 1117 | goto err_destroy_wq; |
fa34ce73 | 1118 | } |
1da177e4 | 1119 | |
1f965b19 | 1120 | wakeup_mirrord(ms); |
1da177e4 | 1121 | return 0; |
a72cf737 DM |
1122 | |
1123 | err_destroy_wq: | |
1124 | destroy_workqueue(ms->kmirrord_wq); | |
1125 | err_free_context: | |
1126 | free_context(ms, ti, ms->nr_mirrors); | |
1127 | return r; | |
1da177e4 LT |
1128 | } |
1129 | ||
1130 | static void mirror_dtr(struct dm_target *ti) | |
1131 | { | |
1132 | struct mirror_set *ms = (struct mirror_set *) ti->private; | |
1133 | ||
a2aebe03 | 1134 | del_timer_sync(&ms->timer); |
6ad36fe2 | 1135 | flush_workqueue(ms->kmirrord_wq); |
43829731 | 1136 | flush_work(&ms->trigger_event); |
eb69aca5 | 1137 | dm_kcopyd_client_destroy(ms->kcopyd_client); |
6ad36fe2 | 1138 | destroy_workqueue(ms->kmirrord_wq); |
1da177e4 LT |
1139 | free_context(ms, ti, ms->nr_mirrors); |
1140 | } | |
1141 | ||
1da177e4 LT |
1142 | /* |
1143 | * Mirror mapping function | |
1144 | */ | |
7de3ee57 | 1145 | static int mirror_map(struct dm_target *ti, struct bio *bio) |
1da177e4 LT |
1146 | { |
1147 | int r, rw = bio_rw(bio); | |
1148 | struct mirror *m; | |
1149 | struct mirror_set *ms = ti->private; | |
1f965b19 | 1150 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
0045d61b MP |
1151 | struct dm_raid1_bio_record *bio_record = |
1152 | dm_per_bio_data(bio, sizeof(struct dm_raid1_bio_record)); | |
1153 | ||
1154 | bio_record->details.bi_bdev = NULL; | |
1da177e4 LT |
1155 | |
1156 | if (rw == WRITE) { | |
06386bbf | 1157 | /* Save region for mirror_end_io() handler */ |
0045d61b | 1158 | bio_record->write_region = dm_rh_bio_to_region(ms->rh, bio); |
1da177e4 | 1159 | queue_bio(ms, bio, rw); |
d2a7ad29 | 1160 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
1161 | } |
1162 | ||
1f965b19 | 1163 | r = log->type->in_sync(log, dm_rh_bio_to_region(ms->rh, bio), 0); |
1da177e4 LT |
1164 | if (r < 0 && r != -EWOULDBLOCK) |
1165 | return r; | |
1166 | ||
1da177e4 | 1167 | /* |
06386bbf | 1168 | * If region is not in-sync queue the bio. |
1da177e4 | 1169 | */ |
06386bbf JB |
1170 | if (!r || (r == -EWOULDBLOCK)) { |
1171 | if (rw == READA) | |
1172 | return -EWOULDBLOCK; | |
1da177e4 | 1173 | |
1da177e4 | 1174 | queue_bio(ms, bio, rw); |
d2a7ad29 | 1175 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
1176 | } |
1177 | ||
06386bbf JB |
1178 | /* |
1179 | * The region is in-sync and we can perform reads directly. | |
1180 | * Store enough information so we can retry if it fails. | |
1181 | */ | |
1da177e4 | 1182 | m = choose_mirror(ms, bio->bi_sector); |
06386bbf | 1183 | if (unlikely(!m)) |
1da177e4 LT |
1184 | return -EIO; |
1185 | ||
89c7cd89 | 1186 | dm_bio_record(&bio_record->details, bio); |
89c7cd89 | 1187 | bio_record->m = m; |
06386bbf JB |
1188 | |
1189 | map_bio(m, bio); | |
1190 | ||
d2a7ad29 | 1191 | return DM_MAPIO_REMAPPED; |
1da177e4 LT |
1192 | } |
1193 | ||
7de3ee57 | 1194 | static int mirror_end_io(struct dm_target *ti, struct bio *bio, int error) |
1da177e4 LT |
1195 | { |
1196 | int rw = bio_rw(bio); | |
1197 | struct mirror_set *ms = (struct mirror_set *) ti->private; | |
06386bbf JB |
1198 | struct mirror *m = NULL; |
1199 | struct dm_bio_details *bd = NULL; | |
0045d61b MP |
1200 | struct dm_raid1_bio_record *bio_record = |
1201 | dm_per_bio_data(bio, sizeof(struct dm_raid1_bio_record)); | |
1da177e4 LT |
1202 | |
1203 | /* | |
1204 | * We need to dec pending if this was a write. | |
1205 | */ | |
06386bbf | 1206 | if (rw == WRITE) { |
751f188d | 1207 | if (!(bio->bi_rw & (REQ_FLUSH | REQ_DISCARD))) |
0045d61b | 1208 | dm_rh_dec(ms->rh, bio_record->write_region); |
06386bbf JB |
1209 | return error; |
1210 | } | |
1da177e4 | 1211 | |
06386bbf JB |
1212 | if (error == -EOPNOTSUPP) |
1213 | goto out; | |
1214 | ||
7b6d91da | 1215 | if ((error == -EWOULDBLOCK) && (bio->bi_rw & REQ_RAHEAD)) |
06386bbf JB |
1216 | goto out; |
1217 | ||
1218 | if (unlikely(error)) { | |
0045d61b | 1219 | if (!bio_record->details.bi_bdev) { |
06386bbf JB |
1220 | /* |
1221 | * There wasn't enough memory to record necessary | |
1222 | * information for a retry or there was no other | |
1223 | * mirror in-sync. | |
1224 | */ | |
e03f1a84 | 1225 | DMERR_LIMIT("Mirror read failed."); |
06386bbf JB |
1226 | return -EIO; |
1227 | } | |
e03f1a84 | 1228 | |
89c7cd89 | 1229 | m = bio_record->m; |
e03f1a84 | 1230 | |
06386bbf JB |
1231 | DMERR("Mirror read failed from %s. Trying alternative device.", |
1232 | m->dev->name); | |
1233 | ||
06386bbf JB |
1234 | fail_mirror(m, DM_RAID1_READ_ERROR); |
1235 | ||
1236 | /* | |
1237 | * A failed read is requeued for another attempt using an intact | |
1238 | * mirror. | |
1239 | */ | |
1240 | if (default_ok(m) || mirror_available(ms, bio)) { | |
89c7cd89 | 1241 | bd = &bio_record->details; |
06386bbf JB |
1242 | |
1243 | dm_bio_restore(bd, bio); | |
0045d61b | 1244 | bio_record->details.bi_bdev = NULL; |
06386bbf | 1245 | queue_bio(ms, bio, rw); |
19cbbc60 | 1246 | return DM_ENDIO_INCOMPLETE; |
06386bbf JB |
1247 | } |
1248 | DMERR("All replicated volumes dead, failing I/O"); | |
1249 | } | |
1250 | ||
1251 | out: | |
0045d61b | 1252 | bio_record->details.bi_bdev = NULL; |
06386bbf JB |
1253 | |
1254 | return error; | |
1da177e4 LT |
1255 | } |
1256 | ||
b80aa7a0 | 1257 | static void mirror_presuspend(struct dm_target *ti) |
1da177e4 LT |
1258 | { |
1259 | struct mirror_set *ms = (struct mirror_set *) ti->private; | |
1f965b19 | 1260 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
1da177e4 | 1261 | |
04788507 MP |
1262 | struct bio_list holds; |
1263 | struct bio *bio; | |
1264 | ||
b80aa7a0 JB |
1265 | atomic_set(&ms->suspend, 1); |
1266 | ||
f0703040 TY |
1267 | /* |
1268 | * Process bios in the hold list to start recovery waiting | |
1269 | * for bios in the hold list. After the process, no bio has | |
1270 | * a chance to be added in the hold list because ms->suspend | |
1271 | * is set. | |
1272 | */ | |
1273 | spin_lock_irq(&ms->lock); | |
1274 | holds = ms->holds; | |
1275 | bio_list_init(&ms->holds); | |
1276 | spin_unlock_irq(&ms->lock); | |
1277 | ||
1278 | while ((bio = bio_list_pop(&holds))) | |
1279 | hold_bio(ms, bio); | |
1280 | ||
b80aa7a0 JB |
1281 | /* |
1282 | * We must finish up all the work that we've | |
1283 | * generated (i.e. recovery work). | |
1284 | */ | |
1f965b19 | 1285 | dm_rh_stop_recovery(ms->rh); |
33184048 | 1286 | |
33184048 | 1287 | wait_event(_kmirrord_recovery_stopped, |
1f965b19 | 1288 | !dm_rh_recovery_in_flight(ms->rh)); |
33184048 | 1289 | |
b80aa7a0 JB |
1290 | if (log->type->presuspend && log->type->presuspend(log)) |
1291 | /* FIXME: need better error handling */ | |
1292 | DMWARN("log presuspend failed"); | |
1293 | ||
1294 | /* | |
1295 | * Now that recovery is complete/stopped and the | |
1296 | * delayed bios are queued, we need to wait for | |
1297 | * the worker thread to complete. This way, | |
1298 | * we know that all of our I/O has been pushed. | |
1299 | */ | |
1300 | flush_workqueue(ms->kmirrord_wq); | |
1301 | } | |
1302 | ||
1303 | static void mirror_postsuspend(struct dm_target *ti) | |
1304 | { | |
1305 | struct mirror_set *ms = ti->private; | |
1f965b19 | 1306 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
b80aa7a0 | 1307 | |
6b3df0d7 | 1308 | if (log->type->postsuspend && log->type->postsuspend(log)) |
1da177e4 | 1309 | /* FIXME: need better error handling */ |
b80aa7a0 | 1310 | DMWARN("log postsuspend failed"); |
1da177e4 LT |
1311 | } |
1312 | ||
1313 | static void mirror_resume(struct dm_target *ti) | |
1314 | { | |
b80aa7a0 | 1315 | struct mirror_set *ms = ti->private; |
1f965b19 | 1316 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
b80aa7a0 JB |
1317 | |
1318 | atomic_set(&ms->suspend, 0); | |
1da177e4 LT |
1319 | if (log->type->resume && log->type->resume(log)) |
1320 | /* FIXME: need better error handling */ | |
1321 | DMWARN("log resume failed"); | |
1f965b19 | 1322 | dm_rh_start_recovery(ms->rh); |
1da177e4 LT |
1323 | } |
1324 | ||
af195ac8 JB |
1325 | /* |
1326 | * device_status_char | |
1327 | * @m: mirror device/leg we want the status of | |
1328 | * | |
1329 | * We return one character representing the most severe error | |
1330 | * we have encountered. | |
1331 | * A => Alive - No failures | |
1332 | * D => Dead - A write failure occurred leaving mirror out-of-sync | |
1333 | * S => Sync - A sychronization failure occurred, mirror out-of-sync | |
1334 | * R => Read - A read failure occurred, mirror data unaffected | |
1335 | * | |
1336 | * Returns: <char> | |
1337 | */ | |
1338 | static char device_status_char(struct mirror *m) | |
1339 | { | |
1340 | if (!atomic_read(&(m->error_count))) | |
1341 | return 'A'; | |
1342 | ||
64b30c46 MP |
1343 | return (test_bit(DM_RAID1_FLUSH_ERROR, &(m->error_type))) ? 'F' : |
1344 | (test_bit(DM_RAID1_WRITE_ERROR, &(m->error_type))) ? 'D' : | |
af195ac8 JB |
1345 | (test_bit(DM_RAID1_SYNC_ERROR, &(m->error_type))) ? 'S' : |
1346 | (test_bit(DM_RAID1_READ_ERROR, &(m->error_type))) ? 'R' : 'U'; | |
1347 | } | |
1348 | ||
1349 | ||
fd7c092e MP |
1350 | static void mirror_status(struct dm_target *ti, status_type_t type, |
1351 | unsigned status_flags, char *result, unsigned maxlen) | |
1da177e4 | 1352 | { |
315dcc22 | 1353 | unsigned int m, sz = 0; |
1da177e4 | 1354 | struct mirror_set *ms = (struct mirror_set *) ti->private; |
1f965b19 | 1355 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
af195ac8 | 1356 | char buffer[ms->nr_mirrors + 1]; |
1da177e4 | 1357 | |
1da177e4 LT |
1358 | switch (type) { |
1359 | case STATUSTYPE_INFO: | |
1360 | DMEMIT("%d ", ms->nr_mirrors); | |
af195ac8 | 1361 | for (m = 0; m < ms->nr_mirrors; m++) { |
1da177e4 | 1362 | DMEMIT("%s ", ms->mirror[m].dev->name); |
af195ac8 JB |
1363 | buffer[m] = device_status_char(&(ms->mirror[m])); |
1364 | } | |
1365 | buffer[m] = '\0'; | |
1da177e4 | 1366 | |
af195ac8 | 1367 | DMEMIT("%llu/%llu 1 %s ", |
1f965b19 | 1368 | (unsigned long long)log->type->get_sync_count(log), |
af195ac8 | 1369 | (unsigned long long)ms->nr_regions, buffer); |
315dcc22 | 1370 | |
1f965b19 | 1371 | sz += log->type->status(log, type, result+sz, maxlen-sz); |
315dcc22 | 1372 | |
1da177e4 LT |
1373 | break; |
1374 | ||
1375 | case STATUSTYPE_TABLE: | |
1f965b19 | 1376 | sz = log->type->status(log, type, result, maxlen); |
315dcc22 | 1377 | |
e52b8f6d | 1378 | DMEMIT("%d", ms->nr_mirrors); |
1da177e4 | 1379 | for (m = 0; m < ms->nr_mirrors; m++) |
e52b8f6d | 1380 | DMEMIT(" %s %llu", ms->mirror[m].dev->name, |
b80aa7a0 | 1381 | (unsigned long long)ms->mirror[m].offset); |
a8e6afa2 JB |
1382 | |
1383 | if (ms->features & DM_RAID1_HANDLE_ERRORS) | |
1384 | DMEMIT(" 1 handle_errors"); | |
1da177e4 | 1385 | } |
1da177e4 LT |
1386 | } |
1387 | ||
af4874e0 MS |
1388 | static int mirror_iterate_devices(struct dm_target *ti, |
1389 | iterate_devices_callout_fn fn, void *data) | |
1390 | { | |
1391 | struct mirror_set *ms = ti->private; | |
1392 | int ret = 0; | |
1393 | unsigned i; | |
1394 | ||
1395 | for (i = 0; !ret && i < ms->nr_mirrors; i++) | |
1396 | ret = fn(ti, ms->mirror[i].dev, | |
5dea271b | 1397 | ms->mirror[i].offset, ti->len, data); |
af4874e0 MS |
1398 | |
1399 | return ret; | |
1400 | } | |
1401 | ||
1da177e4 LT |
1402 | static struct target_type mirror_target = { |
1403 | .name = "mirror", | |
fd7c092e | 1404 | .version = {1, 13, 2}, |
1da177e4 LT |
1405 | .module = THIS_MODULE, |
1406 | .ctr = mirror_ctr, | |
1407 | .dtr = mirror_dtr, | |
1408 | .map = mirror_map, | |
1409 | .end_io = mirror_end_io, | |
b80aa7a0 | 1410 | .presuspend = mirror_presuspend, |
1da177e4 LT |
1411 | .postsuspend = mirror_postsuspend, |
1412 | .resume = mirror_resume, | |
1413 | .status = mirror_status, | |
af4874e0 | 1414 | .iterate_devices = mirror_iterate_devices, |
1da177e4 LT |
1415 | }; |
1416 | ||
1417 | static int __init dm_mirror_init(void) | |
1418 | { | |
1419 | int r; | |
1420 | ||
1da177e4 | 1421 | r = dm_register_target(&mirror_target); |
95f8fac8 | 1422 | if (r < 0) { |
0cd33124 | 1423 | DMERR("Failed to register mirror target"); |
95f8fac8 MP |
1424 | goto bad_target; |
1425 | } | |
1426 | ||
1427 | return 0; | |
1da177e4 | 1428 | |
95f8fac8 | 1429 | bad_target: |
1da177e4 LT |
1430 | return r; |
1431 | } | |
1432 | ||
1433 | static void __exit dm_mirror_exit(void) | |
1434 | { | |
10d3bd09 | 1435 | dm_unregister_target(&mirror_target); |
1da177e4 LT |
1436 | } |
1437 | ||
1438 | /* Module hooks */ | |
1439 | module_init(dm_mirror_init); | |
1440 | module_exit(dm_mirror_exit); | |
1441 | ||
1442 | MODULE_DESCRIPTION(DM_NAME " mirror target"); | |
1443 | MODULE_AUTHOR("Joe Thornber"); | |
1444 | MODULE_LICENSE("GPL"); |