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 | ||
df5d2e90 MP |
85 | DECLARE_DM_KCOPYD_THROTTLE_WITH_MODULE_PARM(raid1_resync_throttle, |
86 | "A percentage of time allocated for raid resynchronization"); | |
87 | ||
1f965b19 | 88 | static void wakeup_mirrord(void *context) |
1da177e4 | 89 | { |
1f965b19 | 90 | struct mirror_set *ms = context; |
1da177e4 | 91 | |
6ad36fe2 HS |
92 | queue_work(ms->kmirrord_wq, &ms->kmirrord_work); |
93 | } | |
94 | ||
a2aebe03 MP |
95 | static void delayed_wake_fn(unsigned long data) |
96 | { | |
97 | struct mirror_set *ms = (struct mirror_set *) data; | |
98 | ||
99 | clear_bit(0, &ms->timer_pending); | |
1f965b19 | 100 | wakeup_mirrord(ms); |
a2aebe03 MP |
101 | } |
102 | ||
103 | static void delayed_wake(struct mirror_set *ms) | |
104 | { | |
105 | if (test_and_set_bit(0, &ms->timer_pending)) | |
106 | return; | |
107 | ||
108 | ms->timer.expires = jiffies + HZ / 5; | |
109 | ms->timer.data = (unsigned long) ms; | |
110 | ms->timer.function = delayed_wake_fn; | |
111 | add_timer(&ms->timer); | |
112 | } | |
113 | ||
1f965b19 | 114 | static void wakeup_all_recovery_waiters(void *context) |
1da177e4 | 115 | { |
1f965b19 | 116 | wake_up_all(&_kmirrord_recovery_stopped); |
1da177e4 LT |
117 | } |
118 | ||
1f965b19 | 119 | static void queue_bio(struct mirror_set *ms, struct bio *bio, int rw) |
1da177e4 LT |
120 | { |
121 | unsigned long flags; | |
1da177e4 | 122 | int should_wake = 0; |
1f965b19 | 123 | struct bio_list *bl; |
1da177e4 | 124 | |
1f965b19 HM |
125 | bl = (rw == WRITE) ? &ms->writes : &ms->reads; |
126 | spin_lock_irqsave(&ms->lock, flags); | |
127 | should_wake = !(bl->head); | |
128 | bio_list_add(bl, bio); | |
129 | spin_unlock_irqrestore(&ms->lock, flags); | |
1da177e4 LT |
130 | |
131 | if (should_wake) | |
1f965b19 | 132 | wakeup_mirrord(ms); |
1da177e4 LT |
133 | } |
134 | ||
1f965b19 | 135 | static void dispatch_bios(void *context, struct bio_list *bio_list) |
1da177e4 | 136 | { |
1f965b19 HM |
137 | struct mirror_set *ms = context; |
138 | struct bio *bio; | |
1da177e4 | 139 | |
1f965b19 HM |
140 | while ((bio = bio_list_pop(bio_list))) |
141 | queue_bio(ms, bio, WRITE); | |
1da177e4 LT |
142 | } |
143 | ||
89c7cd89 | 144 | struct dm_raid1_bio_record { |
06386bbf | 145 | struct mirror *m; |
0045d61b | 146 | /* if details->bi_bdev == NULL, details were not saved */ |
06386bbf | 147 | struct dm_bio_details details; |
0045d61b | 148 | region_t write_region; |
06386bbf JB |
149 | }; |
150 | ||
1da177e4 LT |
151 | /* |
152 | * Every mirror should look like this one. | |
153 | */ | |
154 | #define DEFAULT_MIRROR 0 | |
155 | ||
156 | /* | |
06386bbf JB |
157 | * This is yucky. We squirrel the mirror struct away inside |
158 | * bi_next for read/write buffers. This is safe since the bh | |
1da177e4 LT |
159 | * doesn't get submitted to the lower levels of block layer. |
160 | */ | |
06386bbf | 161 | static struct mirror *bio_get_m(struct bio *bio) |
1da177e4 | 162 | { |
06386bbf | 163 | return (struct mirror *) bio->bi_next; |
1da177e4 LT |
164 | } |
165 | ||
06386bbf | 166 | static void bio_set_m(struct bio *bio, struct mirror *m) |
1da177e4 | 167 | { |
06386bbf | 168 | bio->bi_next = (struct bio *) m; |
1da177e4 LT |
169 | } |
170 | ||
72f4b314 JB |
171 | static struct mirror *get_default_mirror(struct mirror_set *ms) |
172 | { | |
173 | return &ms->mirror[atomic_read(&ms->default_mirror)]; | |
174 | } | |
175 | ||
176 | static void set_default_mirror(struct mirror *m) | |
177 | { | |
178 | struct mirror_set *ms = m->ms; | |
179 | struct mirror *m0 = &(ms->mirror[0]); | |
180 | ||
181 | atomic_set(&ms->default_mirror, m - m0); | |
182 | } | |
183 | ||
87968ddd MP |
184 | static struct mirror *get_valid_mirror(struct mirror_set *ms) |
185 | { | |
186 | struct mirror *m; | |
187 | ||
188 | for (m = ms->mirror; m < ms->mirror + ms->nr_mirrors; m++) | |
189 | if (!atomic_read(&m->error_count)) | |
190 | return m; | |
191 | ||
192 | return NULL; | |
193 | } | |
194 | ||
72f4b314 JB |
195 | /* fail_mirror |
196 | * @m: mirror device to fail | |
197 | * @error_type: one of the enum's, DM_RAID1_*_ERROR | |
198 | * | |
199 | * If errors are being handled, record the type of | |
200 | * error encountered for this device. If this type | |
201 | * of error has already been recorded, we can return; | |
202 | * otherwise, we must signal userspace by triggering | |
203 | * an event. Additionally, if the device is the | |
204 | * primary device, we must choose a new primary, but | |
205 | * only if the mirror is in-sync. | |
206 | * | |
207 | * This function must not block. | |
208 | */ | |
209 | static void fail_mirror(struct mirror *m, enum dm_raid1_error error_type) | |
210 | { | |
211 | struct mirror_set *ms = m->ms; | |
212 | struct mirror *new; | |
213 | ||
929be8fc MP |
214 | ms->leg_failure = 1; |
215 | ||
72f4b314 JB |
216 | /* |
217 | * error_count is used for nothing more than a | |
218 | * simple way to tell if a device has encountered | |
219 | * errors. | |
220 | */ | |
221 | atomic_inc(&m->error_count); | |
222 | ||
223 | if (test_and_set_bit(error_type, &m->error_type)) | |
224 | return; | |
225 | ||
d460c65a JB |
226 | if (!errors_handled(ms)) |
227 | return; | |
228 | ||
72f4b314 JB |
229 | if (m != get_default_mirror(ms)) |
230 | goto out; | |
231 | ||
232 | if (!ms->in_sync) { | |
233 | /* | |
234 | * Better to issue requests to same failing device | |
235 | * than to risk returning corrupt data. | |
236 | */ | |
237 | DMERR("Primary mirror (%s) failed while out-of-sync: " | |
238 | "Reads may fail.", m->dev->name); | |
239 | goto out; | |
240 | } | |
241 | ||
87968ddd MP |
242 | new = get_valid_mirror(ms); |
243 | if (new) | |
244 | set_default_mirror(new); | |
245 | else | |
72f4b314 JB |
246 | DMWARN("All sides of mirror have failed."); |
247 | ||
248 | out: | |
249 | schedule_work(&ms->trigger_event); | |
250 | } | |
251 | ||
c0da3748 MP |
252 | static int mirror_flush(struct dm_target *ti) |
253 | { | |
254 | struct mirror_set *ms = ti->private; | |
255 | unsigned long error_bits; | |
256 | ||
257 | unsigned int i; | |
258 | struct dm_io_region io[ms->nr_mirrors]; | |
259 | struct mirror *m; | |
260 | struct dm_io_request io_req = { | |
d87f4c14 | 261 | .bi_rw = WRITE_FLUSH, |
c0da3748 | 262 | .mem.type = DM_IO_KMEM, |
5fc2ffea | 263 | .mem.ptr.addr = NULL, |
c0da3748 MP |
264 | .client = ms->io_client, |
265 | }; | |
266 | ||
267 | for (i = 0, m = ms->mirror; i < ms->nr_mirrors; i++, m++) { | |
268 | io[i].bdev = m->dev->bdev; | |
269 | io[i].sector = 0; | |
270 | io[i].count = 0; | |
271 | } | |
272 | ||
273 | error_bits = -1; | |
274 | dm_io(&io_req, ms->nr_mirrors, io, &error_bits); | |
275 | if (unlikely(error_bits != 0)) { | |
276 | for (i = 0; i < ms->nr_mirrors; i++) | |
277 | if (test_bit(i, &error_bits)) | |
278 | fail_mirror(ms->mirror + i, | |
64b30c46 | 279 | DM_RAID1_FLUSH_ERROR); |
c0da3748 MP |
280 | return -EIO; |
281 | } | |
282 | ||
283 | return 0; | |
284 | } | |
285 | ||
1da177e4 LT |
286 | /*----------------------------------------------------------------- |
287 | * Recovery. | |
288 | * | |
289 | * When a mirror is first activated we may find that some regions | |
290 | * are in the no-sync state. We have to recover these by | |
291 | * recopying from the default mirror to all the others. | |
292 | *---------------------------------------------------------------*/ | |
4cdc1d1f | 293 | static void recovery_complete(int read_err, unsigned long write_err, |
1da177e4 LT |
294 | void *context) |
295 | { | |
1f965b19 HM |
296 | struct dm_region *reg = context; |
297 | struct mirror_set *ms = dm_rh_region_context(reg); | |
8f0205b7 | 298 | int m, bit = 0; |
1da177e4 | 299 | |
8f0205b7 | 300 | if (read_err) { |
f44db678 JB |
301 | /* Read error means the failure of default mirror. */ |
302 | DMERR_LIMIT("Unable to read primary mirror during recovery"); | |
8f0205b7 JB |
303 | fail_mirror(get_default_mirror(ms), DM_RAID1_SYNC_ERROR); |
304 | } | |
f44db678 | 305 | |
8f0205b7 | 306 | if (write_err) { |
4cdc1d1f | 307 | DMERR_LIMIT("Write error during recovery (error = 0x%lx)", |
f44db678 | 308 | write_err); |
8f0205b7 JB |
309 | /* |
310 | * Bits correspond to devices (excluding default mirror). | |
311 | * The default mirror cannot change during recovery. | |
312 | */ | |
313 | for (m = 0; m < ms->nr_mirrors; m++) { | |
314 | if (&ms->mirror[m] == get_default_mirror(ms)) | |
315 | continue; | |
316 | if (test_bit(bit, &write_err)) | |
317 | fail_mirror(ms->mirror + m, | |
318 | DM_RAID1_SYNC_ERROR); | |
319 | bit++; | |
320 | } | |
321 | } | |
f44db678 | 322 | |
1f965b19 | 323 | dm_rh_recovery_end(reg, !(read_err || write_err)); |
1da177e4 LT |
324 | } |
325 | ||
1f965b19 | 326 | static int recover(struct mirror_set *ms, struct dm_region *reg) |
1da177e4 LT |
327 | { |
328 | int r; | |
1f965b19 | 329 | unsigned i; |
eb69aca5 | 330 | struct dm_io_region from, to[DM_KCOPYD_MAX_REGIONS], *dest; |
1da177e4 LT |
331 | struct mirror *m; |
332 | unsigned long flags = 0; | |
1f965b19 HM |
333 | region_t key = dm_rh_get_region_key(reg); |
334 | sector_t region_size = dm_rh_get_region_size(ms->rh); | |
1da177e4 LT |
335 | |
336 | /* fill in the source */ | |
72f4b314 | 337 | m = get_default_mirror(ms); |
1da177e4 | 338 | from.bdev = m->dev->bdev; |
1f965b19 HM |
339 | from.sector = m->offset + dm_rh_region_to_sector(ms->rh, key); |
340 | if (key == (ms->nr_regions - 1)) { | |
1da177e4 LT |
341 | /* |
342 | * The final region may be smaller than | |
343 | * region_size. | |
344 | */ | |
1f965b19 | 345 | from.count = ms->ti->len & (region_size - 1); |
1da177e4 | 346 | if (!from.count) |
1f965b19 | 347 | from.count = region_size; |
1da177e4 | 348 | } else |
1f965b19 | 349 | from.count = region_size; |
1da177e4 LT |
350 | |
351 | /* fill in the destinations */ | |
352 | for (i = 0, dest = to; i < ms->nr_mirrors; i++) { | |
72f4b314 | 353 | if (&ms->mirror[i] == get_default_mirror(ms)) |
1da177e4 LT |
354 | continue; |
355 | ||
356 | m = ms->mirror + i; | |
357 | dest->bdev = m->dev->bdev; | |
1f965b19 | 358 | dest->sector = m->offset + dm_rh_region_to_sector(ms->rh, key); |
1da177e4 LT |
359 | dest->count = from.count; |
360 | dest++; | |
361 | } | |
362 | ||
363 | /* hand to kcopyd */ | |
f7c83e2e JB |
364 | if (!errors_handled(ms)) |
365 | set_bit(DM_KCOPYD_IGNORE_ERROR, &flags); | |
366 | ||
eb69aca5 HM |
367 | r = dm_kcopyd_copy(ms->kcopyd_client, &from, ms->nr_mirrors - 1, to, |
368 | flags, recovery_complete, reg); | |
1da177e4 LT |
369 | |
370 | return r; | |
371 | } | |
372 | ||
373 | static void do_recovery(struct mirror_set *ms) | |
374 | { | |
1f965b19 HM |
375 | struct dm_region *reg; |
376 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); | |
1da177e4 | 377 | int r; |
1da177e4 LT |
378 | |
379 | /* | |
380 | * Start quiescing some regions. | |
381 | */ | |
1f965b19 | 382 | dm_rh_recovery_prepare(ms->rh); |
1da177e4 LT |
383 | |
384 | /* | |
385 | * Copy any already quiesced regions. | |
386 | */ | |
1f965b19 | 387 | while ((reg = dm_rh_recovery_start(ms->rh))) { |
1da177e4 LT |
388 | r = recover(ms, reg); |
389 | if (r) | |
1f965b19 | 390 | dm_rh_recovery_end(reg, 0); |
1da177e4 LT |
391 | } |
392 | ||
393 | /* | |
394 | * Update the in sync flag. | |
395 | */ | |
396 | if (!ms->in_sync && | |
397 | (log->type->get_sync_count(log) == ms->nr_regions)) { | |
398 | /* the sync is complete */ | |
399 | dm_table_event(ms->ti->table); | |
400 | ms->in_sync = 1; | |
401 | } | |
402 | } | |
403 | ||
404 | /*----------------------------------------------------------------- | |
405 | * Reads | |
406 | *---------------------------------------------------------------*/ | |
407 | static struct mirror *choose_mirror(struct mirror_set *ms, sector_t sector) | |
408 | { | |
06386bbf JB |
409 | struct mirror *m = get_default_mirror(ms); |
410 | ||
411 | do { | |
412 | if (likely(!atomic_read(&m->error_count))) | |
413 | return m; | |
414 | ||
415 | if (m-- == ms->mirror) | |
416 | m += ms->nr_mirrors; | |
417 | } while (m != get_default_mirror(ms)); | |
418 | ||
419 | return NULL; | |
420 | } | |
421 | ||
422 | static int default_ok(struct mirror *m) | |
423 | { | |
424 | struct mirror *default_mirror = get_default_mirror(m->ms); | |
425 | ||
426 | return !atomic_read(&default_mirror->error_count); | |
427 | } | |
428 | ||
429 | static int mirror_available(struct mirror_set *ms, struct bio *bio) | |
430 | { | |
1f965b19 HM |
431 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
432 | region_t region = dm_rh_bio_to_region(ms->rh, bio); | |
06386bbf | 433 | |
1f965b19 | 434 | if (log->type->in_sync(log, region, 0)) |
4f024f37 | 435 | return choose_mirror(ms, bio->bi_iter.bi_sector) ? 1 : 0; |
06386bbf JB |
436 | |
437 | return 0; | |
1da177e4 LT |
438 | } |
439 | ||
440 | /* | |
441 | * remap a buffer to a particular mirror. | |
442 | */ | |
06386bbf JB |
443 | static sector_t map_sector(struct mirror *m, struct bio *bio) |
444 | { | |
4f024f37 | 445 | if (unlikely(!bio->bi_iter.bi_size)) |
4184153f | 446 | return 0; |
4f024f37 | 447 | return m->offset + dm_target_offset(m->ms->ti, bio->bi_iter.bi_sector); |
06386bbf JB |
448 | } |
449 | ||
450 | static void map_bio(struct mirror *m, struct bio *bio) | |
1da177e4 LT |
451 | { |
452 | bio->bi_bdev = m->dev->bdev; | |
4f024f37 | 453 | bio->bi_iter.bi_sector = map_sector(m, bio); |
06386bbf JB |
454 | } |
455 | ||
22a1ceb1 | 456 | static void map_region(struct dm_io_region *io, struct mirror *m, |
06386bbf JB |
457 | struct bio *bio) |
458 | { | |
459 | io->bdev = m->dev->bdev; | |
460 | io->sector = map_sector(m, bio); | |
aa8b57aa | 461 | io->count = bio_sectors(bio); |
06386bbf JB |
462 | } |
463 | ||
04788507 MP |
464 | static void hold_bio(struct mirror_set *ms, struct bio *bio) |
465 | { | |
466 | /* | |
f0703040 TY |
467 | * Lock is required to avoid race condition during suspend |
468 | * process. | |
04788507 | 469 | */ |
f0703040 TY |
470 | spin_lock_irq(&ms->lock); |
471 | ||
04788507 | 472 | if (atomic_read(&ms->suspend)) { |
f0703040 TY |
473 | spin_unlock_irq(&ms->lock); |
474 | ||
475 | /* | |
476 | * If device is suspended, complete the bio. | |
477 | */ | |
04788507 MP |
478 | if (dm_noflush_suspending(ms->ti)) |
479 | bio_endio(bio, DM_ENDIO_REQUEUE); | |
480 | else | |
481 | bio_endio(bio, -EIO); | |
482 | return; | |
483 | } | |
484 | ||
485 | /* | |
486 | * Hold bio until the suspend is complete. | |
487 | */ | |
04788507 MP |
488 | bio_list_add(&ms->holds, bio); |
489 | spin_unlock_irq(&ms->lock); | |
490 | } | |
491 | ||
06386bbf JB |
492 | /*----------------------------------------------------------------- |
493 | * Reads | |
494 | *---------------------------------------------------------------*/ | |
495 | static void read_callback(unsigned long error, void *context) | |
496 | { | |
497 | struct bio *bio = context; | |
498 | struct mirror *m; | |
499 | ||
500 | m = bio_get_m(bio); | |
501 | bio_set_m(bio, NULL); | |
502 | ||
503 | if (likely(!error)) { | |
504 | bio_endio(bio, 0); | |
505 | return; | |
506 | } | |
507 | ||
508 | fail_mirror(m, DM_RAID1_READ_ERROR); | |
509 | ||
510 | if (likely(default_ok(m)) || mirror_available(m->ms, bio)) { | |
511 | DMWARN_LIMIT("Read failure on mirror device %s. " | |
512 | "Trying alternative device.", | |
513 | m->dev->name); | |
514 | queue_bio(m->ms, bio, bio_rw(bio)); | |
515 | return; | |
516 | } | |
517 | ||
518 | DMERR_LIMIT("Read failure on mirror device %s. Failing I/O.", | |
519 | m->dev->name); | |
520 | bio_endio(bio, -EIO); | |
521 | } | |
522 | ||
523 | /* Asynchronous read. */ | |
524 | static void read_async_bio(struct mirror *m, struct bio *bio) | |
525 | { | |
22a1ceb1 | 526 | struct dm_io_region io; |
06386bbf JB |
527 | struct dm_io_request io_req = { |
528 | .bi_rw = READ, | |
003b5c57 KO |
529 | .mem.type = DM_IO_BIO, |
530 | .mem.ptr.bio = bio, | |
06386bbf JB |
531 | .notify.fn = read_callback, |
532 | .notify.context = bio, | |
533 | .client = m->ms->io_client, | |
534 | }; | |
535 | ||
536 | map_region(&io, m, bio); | |
537 | bio_set_m(bio, m); | |
1f965b19 HM |
538 | BUG_ON(dm_io(&io_req, 1, &io, NULL)); |
539 | } | |
540 | ||
541 | static inline int region_in_sync(struct mirror_set *ms, region_t region, | |
542 | int may_block) | |
543 | { | |
544 | int state = dm_rh_get_state(ms->rh, region, may_block); | |
545 | return state == DM_RH_CLEAN || state == DM_RH_DIRTY; | |
1da177e4 LT |
546 | } |
547 | ||
548 | static void do_reads(struct mirror_set *ms, struct bio_list *reads) | |
549 | { | |
550 | region_t region; | |
551 | struct bio *bio; | |
552 | struct mirror *m; | |
553 | ||
554 | while ((bio = bio_list_pop(reads))) { | |
1f965b19 | 555 | region = dm_rh_bio_to_region(ms->rh, bio); |
06386bbf | 556 | m = get_default_mirror(ms); |
1da177e4 LT |
557 | |
558 | /* | |
559 | * We can only read balance if the region is in sync. | |
560 | */ | |
1f965b19 | 561 | if (likely(region_in_sync(ms, region, 1))) |
4f024f37 | 562 | m = choose_mirror(ms, bio->bi_iter.bi_sector); |
06386bbf JB |
563 | else if (m && atomic_read(&m->error_count)) |
564 | m = NULL; | |
1da177e4 | 565 | |
06386bbf JB |
566 | if (likely(m)) |
567 | read_async_bio(m, bio); | |
568 | else | |
569 | bio_endio(bio, -EIO); | |
1da177e4 LT |
570 | } |
571 | } | |
572 | ||
573 | /*----------------------------------------------------------------- | |
574 | * Writes. | |
575 | * | |
576 | * We do different things with the write io depending on the | |
577 | * state of the region that it's in: | |
578 | * | |
579 | * SYNC: increment pending, use kcopyd to write to *all* mirrors | |
580 | * RECOVERING: delay the io until recovery completes | |
581 | * NOSYNC: increment pending, just write to the default mirror | |
582 | *---------------------------------------------------------------*/ | |
72f4b314 | 583 | |
72f4b314 | 584 | |
1da177e4 LT |
585 | static void write_callback(unsigned long error, void *context) |
586 | { | |
72f4b314 | 587 | unsigned i, ret = 0; |
1da177e4 LT |
588 | struct bio *bio = (struct bio *) context; |
589 | struct mirror_set *ms; | |
72f4b314 JB |
590 | int should_wake = 0; |
591 | unsigned long flags; | |
1da177e4 | 592 | |
06386bbf JB |
593 | ms = bio_get_m(bio)->ms; |
594 | bio_set_m(bio, NULL); | |
1da177e4 LT |
595 | |
596 | /* | |
597 | * NOTE: We don't decrement the pending count here, | |
598 | * instead it is done by the targets endio function. | |
599 | * This way we handle both writes to SYNC and NOSYNC | |
600 | * regions with the same code. | |
601 | */ | |
60f355ea MP |
602 | if (likely(!error)) { |
603 | bio_endio(bio, ret); | |
604 | return; | |
605 | } | |
1da177e4 | 606 | |
f2ed51ac MP |
607 | /* |
608 | * If the bio is discard, return an error, but do not | |
609 | * degrade the array. | |
610 | */ | |
611 | if (bio->bi_rw & REQ_DISCARD) { | |
612 | bio_endio(bio, -EOPNOTSUPP); | |
613 | return; | |
614 | } | |
615 | ||
72f4b314 JB |
616 | for (i = 0; i < ms->nr_mirrors; i++) |
617 | if (test_bit(i, &error)) | |
618 | fail_mirror(ms->mirror + i, DM_RAID1_WRITE_ERROR); | |
72f4b314 | 619 | |
60f355ea MP |
620 | /* |
621 | * Need to raise event. Since raising | |
622 | * events can block, we need to do it in | |
623 | * the main thread. | |
624 | */ | |
625 | spin_lock_irqsave(&ms->lock, flags); | |
626 | if (!ms->failures.head) | |
627 | should_wake = 1; | |
628 | bio_list_add(&ms->failures, bio); | |
629 | spin_unlock_irqrestore(&ms->lock, flags); | |
630 | if (should_wake) | |
631 | wakeup_mirrord(ms); | |
1da177e4 LT |
632 | } |
633 | ||
634 | static void do_write(struct mirror_set *ms, struct bio *bio) | |
635 | { | |
636 | unsigned int i; | |
22a1ceb1 | 637 | struct dm_io_region io[ms->nr_mirrors], *dest = io; |
1da177e4 | 638 | struct mirror *m; |
88be163a | 639 | struct dm_io_request io_req = { |
d87f4c14 | 640 | .bi_rw = WRITE | (bio->bi_rw & WRITE_FLUSH_FUA), |
003b5c57 KO |
641 | .mem.type = DM_IO_BIO, |
642 | .mem.ptr.bio = bio, | |
88be163a MB |
643 | .notify.fn = write_callback, |
644 | .notify.context = bio, | |
645 | .client = ms->io_client, | |
646 | }; | |
1da177e4 | 647 | |
5fc2ffea MS |
648 | if (bio->bi_rw & REQ_DISCARD) { |
649 | io_req.bi_rw |= REQ_DISCARD; | |
650 | io_req.mem.type = DM_IO_KMEM; | |
651 | io_req.mem.ptr.addr = NULL; | |
652 | } | |
653 | ||
06386bbf JB |
654 | for (i = 0, m = ms->mirror; i < ms->nr_mirrors; i++, m++) |
655 | map_region(dest++, m, bio); | |
1da177e4 | 656 | |
06386bbf JB |
657 | /* |
658 | * Use default mirror because we only need it to retrieve the reference | |
659 | * to the mirror set in write_callback(). | |
660 | */ | |
661 | bio_set_m(bio, get_default_mirror(ms)); | |
88be163a | 662 | |
1f965b19 | 663 | BUG_ON(dm_io(&io_req, ms->nr_mirrors, io, NULL)); |
1da177e4 LT |
664 | } |
665 | ||
666 | static void do_writes(struct mirror_set *ms, struct bio_list *writes) | |
667 | { | |
668 | int state; | |
669 | struct bio *bio; | |
670 | struct bio_list sync, nosync, recover, *this_list = NULL; | |
7513c2a7 JB |
671 | struct bio_list requeue; |
672 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); | |
673 | region_t region; | |
1da177e4 LT |
674 | |
675 | if (!writes->head) | |
676 | return; | |
677 | ||
678 | /* | |
679 | * Classify each write. | |
680 | */ | |
681 | bio_list_init(&sync); | |
682 | bio_list_init(&nosync); | |
683 | bio_list_init(&recover); | |
7513c2a7 | 684 | bio_list_init(&requeue); |
1da177e4 LT |
685 | |
686 | while ((bio = bio_list_pop(writes))) { | |
5fc2ffea MS |
687 | if ((bio->bi_rw & REQ_FLUSH) || |
688 | (bio->bi_rw & REQ_DISCARD)) { | |
4184153f MP |
689 | bio_list_add(&sync, bio); |
690 | continue; | |
691 | } | |
692 | ||
7513c2a7 JB |
693 | region = dm_rh_bio_to_region(ms->rh, bio); |
694 | ||
695 | if (log->type->is_remote_recovering && | |
696 | log->type->is_remote_recovering(log, region)) { | |
697 | bio_list_add(&requeue, bio); | |
698 | continue; | |
699 | } | |
700 | ||
701 | state = dm_rh_get_state(ms->rh, region, 1); | |
1da177e4 | 702 | switch (state) { |
1f965b19 HM |
703 | case DM_RH_CLEAN: |
704 | case DM_RH_DIRTY: | |
1da177e4 LT |
705 | this_list = &sync; |
706 | break; | |
707 | ||
1f965b19 | 708 | case DM_RH_NOSYNC: |
1da177e4 LT |
709 | this_list = &nosync; |
710 | break; | |
711 | ||
1f965b19 | 712 | case DM_RH_RECOVERING: |
1da177e4 LT |
713 | this_list = &recover; |
714 | break; | |
715 | } | |
716 | ||
717 | bio_list_add(this_list, bio); | |
718 | } | |
719 | ||
7513c2a7 JB |
720 | /* |
721 | * Add bios that are delayed due to remote recovery | |
722 | * back on to the write queue | |
723 | */ | |
724 | if (unlikely(requeue.head)) { | |
725 | spin_lock_irq(&ms->lock); | |
726 | bio_list_merge(&ms->writes, &requeue); | |
727 | spin_unlock_irq(&ms->lock); | |
69885683 | 728 | delayed_wake(ms); |
7513c2a7 JB |
729 | } |
730 | ||
1da177e4 LT |
731 | /* |
732 | * Increment the pending counts for any regions that will | |
733 | * be written to (writes to recover regions are going to | |
734 | * be delayed). | |
735 | */ | |
1f965b19 HM |
736 | dm_rh_inc_pending(ms->rh, &sync); |
737 | dm_rh_inc_pending(ms->rh, &nosync); | |
d2b69864 JB |
738 | |
739 | /* | |
740 | * If the flush fails on a previous call and succeeds here, | |
741 | * we must not reset the log_failure variable. We need | |
742 | * userspace interaction to do that. | |
743 | */ | |
744 | ms->log_failure = dm_rh_flush(ms->rh) ? 1 : ms->log_failure; | |
1da177e4 LT |
745 | |
746 | /* | |
747 | * Dispatch io. | |
748 | */ | |
5528d17d | 749 | if (unlikely(ms->log_failure) && errors_handled(ms)) { |
b80aa7a0 JB |
750 | spin_lock_irq(&ms->lock); |
751 | bio_list_merge(&ms->failures, &sync); | |
752 | spin_unlock_irq(&ms->lock); | |
1f965b19 | 753 | wakeup_mirrord(ms); |
b80aa7a0 | 754 | } else |
fc1ff958 | 755 | while ((bio = bio_list_pop(&sync))) |
b80aa7a0 | 756 | do_write(ms, bio); |
1da177e4 LT |
757 | |
758 | while ((bio = bio_list_pop(&recover))) | |
1f965b19 | 759 | dm_rh_delay(ms->rh, bio); |
1da177e4 LT |
760 | |
761 | while ((bio = bio_list_pop(&nosync))) { | |
ede5ea0b MP |
762 | if (unlikely(ms->leg_failure) && errors_handled(ms)) { |
763 | spin_lock_irq(&ms->lock); | |
764 | bio_list_add(&ms->failures, bio); | |
765 | spin_unlock_irq(&ms->lock); | |
766 | wakeup_mirrord(ms); | |
767 | } else { | |
929be8fc MP |
768 | map_bio(get_default_mirror(ms), bio); |
769 | generic_make_request(bio); | |
770 | } | |
1da177e4 LT |
771 | } |
772 | } | |
773 | ||
72f4b314 JB |
774 | static void do_failures(struct mirror_set *ms, struct bio_list *failures) |
775 | { | |
776 | struct bio *bio; | |
777 | ||
0f398a84 | 778 | if (likely(!failures->head)) |
72f4b314 JB |
779 | return; |
780 | ||
b80aa7a0 JB |
781 | /* |
782 | * If the log has failed, unattempted writes are being | |
0f398a84 | 783 | * put on the holds list. We can't issue those writes |
b80aa7a0 JB |
784 | * until a log has been marked, so we must store them. |
785 | * | |
786 | * If a 'noflush' suspend is in progress, we can requeue | |
787 | * the I/O's to the core. This give userspace a chance | |
788 | * to reconfigure the mirror, at which point the core | |
789 | * will reissue the writes. If the 'noflush' flag is | |
790 | * not set, we have no choice but to return errors. | |
791 | * | |
792 | * Some writes on the failures list may have been | |
793 | * submitted before the log failure and represent a | |
794 | * failure to write to one of the devices. It is ok | |
795 | * for us to treat them the same and requeue them | |
796 | * as well. | |
797 | */ | |
0f398a84 | 798 | while ((bio = bio_list_pop(failures))) { |
60f355ea | 799 | if (!ms->log_failure) { |
0f398a84 | 800 | ms->in_sync = 0; |
c58098be | 801 | dm_rh_mark_nosync(ms->rh, bio); |
0f398a84 | 802 | } |
60f355ea MP |
803 | |
804 | /* | |
805 | * If all the legs are dead, fail the I/O. | |
806 | * If we have been told to handle errors, hold the bio | |
807 | * and wait for userspace to deal with the problem. | |
808 | * Otherwise pretend that the I/O succeeded. (This would | |
809 | * be wrong if the failed leg returned after reboot and | |
810 | * got replicated back to the good legs.) | |
811 | */ | |
812 | if (!get_valid_mirror(ms)) | |
813 | bio_endio(bio, -EIO); | |
814 | else if (errors_handled(ms)) | |
815 | hold_bio(ms, bio); | |
816 | else | |
817 | bio_endio(bio, 0); | |
b80aa7a0 | 818 | } |
72f4b314 JB |
819 | } |
820 | ||
821 | static void trigger_event(struct work_struct *work) | |
822 | { | |
823 | struct mirror_set *ms = | |
824 | container_of(work, struct mirror_set, trigger_event); | |
825 | ||
826 | dm_table_event(ms->ti->table); | |
827 | } | |
828 | ||
1da177e4 LT |
829 | /*----------------------------------------------------------------- |
830 | * kmirrord | |
831 | *---------------------------------------------------------------*/ | |
a2aebe03 | 832 | static void do_mirror(struct work_struct *work) |
1da177e4 | 833 | { |
1f965b19 HM |
834 | struct mirror_set *ms = container_of(work, struct mirror_set, |
835 | kmirrord_work); | |
72f4b314 JB |
836 | struct bio_list reads, writes, failures; |
837 | unsigned long flags; | |
1da177e4 | 838 | |
72f4b314 | 839 | spin_lock_irqsave(&ms->lock, flags); |
1da177e4 LT |
840 | reads = ms->reads; |
841 | writes = ms->writes; | |
72f4b314 | 842 | failures = ms->failures; |
1da177e4 LT |
843 | bio_list_init(&ms->reads); |
844 | bio_list_init(&ms->writes); | |
72f4b314 JB |
845 | bio_list_init(&ms->failures); |
846 | spin_unlock_irqrestore(&ms->lock, flags); | |
1da177e4 | 847 | |
1f965b19 | 848 | dm_rh_update_states(ms->rh, errors_handled(ms)); |
1da177e4 LT |
849 | do_recovery(ms); |
850 | do_reads(ms, &reads); | |
851 | do_writes(ms, &writes); | |
72f4b314 | 852 | do_failures(ms, &failures); |
1da177e4 LT |
853 | } |
854 | ||
1da177e4 LT |
855 | /*----------------------------------------------------------------- |
856 | * Target functions | |
857 | *---------------------------------------------------------------*/ | |
858 | static struct mirror_set *alloc_context(unsigned int nr_mirrors, | |
859 | uint32_t region_size, | |
860 | struct dm_target *ti, | |
416cd17b | 861 | struct dm_dirty_log *dl) |
1da177e4 LT |
862 | { |
863 | size_t len; | |
864 | struct mirror_set *ms = NULL; | |
865 | ||
1da177e4 LT |
866 | len = sizeof(*ms) + (sizeof(ms->mirror[0]) * nr_mirrors); |
867 | ||
dd00cc48 | 868 | ms = kzalloc(len, GFP_KERNEL); |
1da177e4 | 869 | if (!ms) { |
72d94861 | 870 | ti->error = "Cannot allocate mirror context"; |
1da177e4 LT |
871 | return NULL; |
872 | } | |
873 | ||
1da177e4 | 874 | spin_lock_init(&ms->lock); |
5339fc2d MP |
875 | bio_list_init(&ms->reads); |
876 | bio_list_init(&ms->writes); | |
877 | bio_list_init(&ms->failures); | |
878 | bio_list_init(&ms->holds); | |
1da177e4 LT |
879 | |
880 | ms->ti = ti; | |
881 | ms->nr_mirrors = nr_mirrors; | |
882 | ms->nr_regions = dm_sector_div_up(ti->len, region_size); | |
883 | ms->in_sync = 0; | |
b80aa7a0 | 884 | ms->log_failure = 0; |
929be8fc | 885 | ms->leg_failure = 0; |
b80aa7a0 | 886 | atomic_set(&ms->suspend, 0); |
72f4b314 | 887 | atomic_set(&ms->default_mirror, DEFAULT_MIRROR); |
1da177e4 | 888 | |
bda8efec | 889 | ms->io_client = dm_io_client_create(); |
88be163a MB |
890 | if (IS_ERR(ms->io_client)) { |
891 | ti->error = "Error creating dm_io client"; | |
892 | kfree(ms); | |
893 | return NULL; | |
894 | } | |
895 | ||
1f965b19 HM |
896 | ms->rh = dm_region_hash_create(ms, dispatch_bios, wakeup_mirrord, |
897 | wakeup_all_recovery_waiters, | |
898 | ms->ti->begin, MAX_RECOVERY, | |
899 | dl, region_size, ms->nr_regions); | |
900 | if (IS_ERR(ms->rh)) { | |
72d94861 | 901 | ti->error = "Error creating dirty region hash"; |
a72cf737 | 902 | dm_io_client_destroy(ms->io_client); |
1da177e4 LT |
903 | kfree(ms); |
904 | return NULL; | |
905 | } | |
906 | ||
907 | return ms; | |
908 | } | |
909 | ||
910 | static void free_context(struct mirror_set *ms, struct dm_target *ti, | |
911 | unsigned int m) | |
912 | { | |
913 | while (m--) | |
914 | dm_put_device(ti, ms->mirror[m].dev); | |
915 | ||
88be163a | 916 | dm_io_client_destroy(ms->io_client); |
1f965b19 | 917 | dm_region_hash_destroy(ms->rh); |
1da177e4 LT |
918 | kfree(ms); |
919 | } | |
920 | ||
1da177e4 LT |
921 | static int get_mirror(struct mirror_set *ms, struct dm_target *ti, |
922 | unsigned int mirror, char **argv) | |
923 | { | |
4ee218cd | 924 | unsigned long long offset; |
31998ef1 | 925 | char dummy; |
1da177e4 | 926 | |
31998ef1 | 927 | if (sscanf(argv[1], "%llu%c", &offset, &dummy) != 1) { |
72d94861 | 928 | ti->error = "Invalid offset"; |
1da177e4 LT |
929 | return -EINVAL; |
930 | } | |
931 | ||
8215d6ec | 932 | if (dm_get_device(ti, argv[0], dm_table_get_mode(ti->table), |
1da177e4 | 933 | &ms->mirror[mirror].dev)) { |
72d94861 | 934 | ti->error = "Device lookup failure"; |
1da177e4 LT |
935 | return -ENXIO; |
936 | } | |
937 | ||
aa5617c5 | 938 | ms->mirror[mirror].ms = ms; |
72f4b314 JB |
939 | atomic_set(&(ms->mirror[mirror].error_count), 0); |
940 | ms->mirror[mirror].error_type = 0; | |
1da177e4 LT |
941 | ms->mirror[mirror].offset = offset; |
942 | ||
943 | return 0; | |
944 | } | |
945 | ||
1da177e4 LT |
946 | /* |
947 | * Create dirty log: log_type #log_params <log_params> | |
948 | */ | |
416cd17b | 949 | static struct dm_dirty_log *create_dirty_log(struct dm_target *ti, |
1f965b19 HM |
950 | unsigned argc, char **argv, |
951 | unsigned *args_used) | |
1da177e4 | 952 | { |
1f965b19 | 953 | unsigned param_count; |
416cd17b | 954 | struct dm_dirty_log *dl; |
31998ef1 | 955 | char dummy; |
1da177e4 LT |
956 | |
957 | if (argc < 2) { | |
72d94861 | 958 | ti->error = "Insufficient mirror log arguments"; |
1da177e4 LT |
959 | return NULL; |
960 | } | |
961 | ||
31998ef1 | 962 | if (sscanf(argv[1], "%u%c", ¶m_count, &dummy) != 1) { |
72d94861 | 963 | ti->error = "Invalid mirror log argument count"; |
1da177e4 LT |
964 | return NULL; |
965 | } | |
966 | ||
967 | *args_used = 2 + param_count; | |
968 | ||
969 | if (argc < *args_used) { | |
72d94861 | 970 | ti->error = "Insufficient mirror log arguments"; |
1da177e4 LT |
971 | return NULL; |
972 | } | |
973 | ||
c0da3748 MP |
974 | dl = dm_dirty_log_create(argv[0], ti, mirror_flush, param_count, |
975 | argv + 2); | |
1da177e4 | 976 | if (!dl) { |
72d94861 | 977 | ti->error = "Error creating mirror dirty log"; |
1da177e4 LT |
978 | return NULL; |
979 | } | |
980 | ||
1da177e4 LT |
981 | return dl; |
982 | } | |
983 | ||
a8e6afa2 JB |
984 | static int parse_features(struct mirror_set *ms, unsigned argc, char **argv, |
985 | unsigned *args_used) | |
986 | { | |
987 | unsigned num_features; | |
988 | struct dm_target *ti = ms->ti; | |
31998ef1 | 989 | char dummy; |
a8e6afa2 JB |
990 | |
991 | *args_used = 0; | |
992 | ||
993 | if (!argc) | |
994 | return 0; | |
995 | ||
31998ef1 | 996 | if (sscanf(argv[0], "%u%c", &num_features, &dummy) != 1) { |
a8e6afa2 JB |
997 | ti->error = "Invalid number of features"; |
998 | return -EINVAL; | |
999 | } | |
1000 | ||
1001 | argc--; | |
1002 | argv++; | |
1003 | (*args_used)++; | |
1004 | ||
1005 | if (num_features > argc) { | |
1006 | ti->error = "Not enough arguments to support feature count"; | |
1007 | return -EINVAL; | |
1008 | } | |
1009 | ||
1010 | if (!strcmp("handle_errors", argv[0])) | |
1011 | ms->features |= DM_RAID1_HANDLE_ERRORS; | |
1012 | else { | |
1013 | ti->error = "Unrecognised feature requested"; | |
1014 | return -EINVAL; | |
1015 | } | |
1016 | ||
1017 | (*args_used)++; | |
1018 | ||
1019 | return 0; | |
1020 | } | |
1021 | ||
1da177e4 LT |
1022 | /* |
1023 | * Construct a mirror mapping: | |
1024 | * | |
1025 | * log_type #log_params <log_params> | |
1026 | * #mirrors [mirror_path offset]{2,} | |
a8e6afa2 | 1027 | * [#features <features>] |
1da177e4 LT |
1028 | * |
1029 | * log_type is "core" or "disk" | |
1030 | * #log_params is between 1 and 3 | |
a8e6afa2 JB |
1031 | * |
1032 | * If present, features must be "handle_errors". | |
1da177e4 | 1033 | */ |
1da177e4 LT |
1034 | static int mirror_ctr(struct dm_target *ti, unsigned int argc, char **argv) |
1035 | { | |
1036 | int r; | |
1037 | unsigned int nr_mirrors, m, args_used; | |
1038 | struct mirror_set *ms; | |
416cd17b | 1039 | struct dm_dirty_log *dl; |
31998ef1 | 1040 | char dummy; |
1da177e4 LT |
1041 | |
1042 | dl = create_dirty_log(ti, argc, argv, &args_used); | |
1043 | if (!dl) | |
1044 | return -EINVAL; | |
1045 | ||
1046 | argv += args_used; | |
1047 | argc -= args_used; | |
1048 | ||
31998ef1 | 1049 | if (!argc || sscanf(argv[0], "%u%c", &nr_mirrors, &dummy) != 1 || |
eb69aca5 | 1050 | nr_mirrors < 2 || nr_mirrors > DM_KCOPYD_MAX_REGIONS + 1) { |
72d94861 | 1051 | ti->error = "Invalid number of mirrors"; |
416cd17b | 1052 | dm_dirty_log_destroy(dl); |
1da177e4 LT |
1053 | return -EINVAL; |
1054 | } | |
1055 | ||
1056 | argv++, argc--; | |
1057 | ||
a8e6afa2 JB |
1058 | if (argc < nr_mirrors * 2) { |
1059 | ti->error = "Too few mirror arguments"; | |
416cd17b | 1060 | dm_dirty_log_destroy(dl); |
1da177e4 LT |
1061 | return -EINVAL; |
1062 | } | |
1063 | ||
1064 | ms = alloc_context(nr_mirrors, dl->type->get_region_size(dl), ti, dl); | |
1065 | if (!ms) { | |
416cd17b | 1066 | dm_dirty_log_destroy(dl); |
1da177e4 LT |
1067 | return -ENOMEM; |
1068 | } | |
1069 | ||
1070 | /* Get the mirror parameter sets */ | |
1071 | for (m = 0; m < nr_mirrors; m++) { | |
1072 | r = get_mirror(ms, ti, m, argv); | |
1073 | if (r) { | |
1074 | free_context(ms, ti, m); | |
1075 | return r; | |
1076 | } | |
1077 | argv += 2; | |
1078 | argc -= 2; | |
1079 | } | |
1080 | ||
1081 | ti->private = ms; | |
542f9038 MS |
1082 | |
1083 | r = dm_set_target_max_io_len(ti, dm_rh_get_region_size(ms->rh)); | |
1084 | if (r) | |
1085 | goto err_free_context; | |
1086 | ||
55a62eef AK |
1087 | ti->num_flush_bios = 1; |
1088 | ti->num_discard_bios = 1; | |
89c7cd89 | 1089 | ti->per_bio_data_size = sizeof(struct dm_raid1_bio_record); |
0ac55489 | 1090 | ti->discard_zeroes_data_unsupported = true; |
1da177e4 | 1091 | |
670368a8 | 1092 | ms->kmirrord_wq = alloc_workqueue("kmirrord", WQ_MEM_RECLAIM, 0); |
6ad36fe2 HS |
1093 | if (!ms->kmirrord_wq) { |
1094 | DMERR("couldn't start kmirrord"); | |
a72cf737 DM |
1095 | r = -ENOMEM; |
1096 | goto err_free_context; | |
6ad36fe2 HS |
1097 | } |
1098 | INIT_WORK(&ms->kmirrord_work, do_mirror); | |
a2aebe03 MP |
1099 | init_timer(&ms->timer); |
1100 | ms->timer_pending = 0; | |
72f4b314 | 1101 | INIT_WORK(&ms->trigger_event, trigger_event); |
6ad36fe2 | 1102 | |
a8e6afa2 | 1103 | r = parse_features(ms, argc, argv, &args_used); |
a72cf737 DM |
1104 | if (r) |
1105 | goto err_destroy_wq; | |
a8e6afa2 JB |
1106 | |
1107 | argv += args_used; | |
1108 | argc -= args_used; | |
1109 | ||
f44db678 JB |
1110 | /* |
1111 | * Any read-balancing addition depends on the | |
1112 | * DM_RAID1_HANDLE_ERRORS flag being present. | |
1113 | * This is because the decision to balance depends | |
1114 | * on the sync state of a region. If the above | |
1115 | * flag is not present, we ignore errors; and | |
1116 | * the sync state may be inaccurate. | |
1117 | */ | |
1118 | ||
a8e6afa2 JB |
1119 | if (argc) { |
1120 | ti->error = "Too many mirror arguments"; | |
a72cf737 DM |
1121 | r = -EINVAL; |
1122 | goto err_destroy_wq; | |
a8e6afa2 JB |
1123 | } |
1124 | ||
df5d2e90 | 1125 | ms->kcopyd_client = dm_kcopyd_client_create(&dm_kcopyd_throttle); |
fa34ce73 MP |
1126 | if (IS_ERR(ms->kcopyd_client)) { |
1127 | r = PTR_ERR(ms->kcopyd_client); | |
a72cf737 | 1128 | goto err_destroy_wq; |
fa34ce73 | 1129 | } |
1da177e4 | 1130 | |
1f965b19 | 1131 | wakeup_mirrord(ms); |
1da177e4 | 1132 | return 0; |
a72cf737 DM |
1133 | |
1134 | err_destroy_wq: | |
1135 | destroy_workqueue(ms->kmirrord_wq); | |
1136 | err_free_context: | |
1137 | free_context(ms, ti, ms->nr_mirrors); | |
1138 | return r; | |
1da177e4 LT |
1139 | } |
1140 | ||
1141 | static void mirror_dtr(struct dm_target *ti) | |
1142 | { | |
1143 | struct mirror_set *ms = (struct mirror_set *) ti->private; | |
1144 | ||
a2aebe03 | 1145 | del_timer_sync(&ms->timer); |
6ad36fe2 | 1146 | flush_workqueue(ms->kmirrord_wq); |
43829731 | 1147 | flush_work(&ms->trigger_event); |
eb69aca5 | 1148 | dm_kcopyd_client_destroy(ms->kcopyd_client); |
6ad36fe2 | 1149 | destroy_workqueue(ms->kmirrord_wq); |
1da177e4 LT |
1150 | free_context(ms, ti, ms->nr_mirrors); |
1151 | } | |
1152 | ||
1da177e4 LT |
1153 | /* |
1154 | * Mirror mapping function | |
1155 | */ | |
7de3ee57 | 1156 | static int mirror_map(struct dm_target *ti, struct bio *bio) |
1da177e4 LT |
1157 | { |
1158 | int r, rw = bio_rw(bio); | |
1159 | struct mirror *m; | |
1160 | struct mirror_set *ms = ti->private; | |
1f965b19 | 1161 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
0045d61b MP |
1162 | struct dm_raid1_bio_record *bio_record = |
1163 | dm_per_bio_data(bio, sizeof(struct dm_raid1_bio_record)); | |
1164 | ||
1165 | bio_record->details.bi_bdev = NULL; | |
1da177e4 LT |
1166 | |
1167 | if (rw == WRITE) { | |
06386bbf | 1168 | /* Save region for mirror_end_io() handler */ |
0045d61b | 1169 | bio_record->write_region = dm_rh_bio_to_region(ms->rh, bio); |
1da177e4 | 1170 | queue_bio(ms, bio, rw); |
d2a7ad29 | 1171 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
1172 | } |
1173 | ||
1f965b19 | 1174 | r = log->type->in_sync(log, dm_rh_bio_to_region(ms->rh, bio), 0); |
1da177e4 LT |
1175 | if (r < 0 && r != -EWOULDBLOCK) |
1176 | return r; | |
1177 | ||
1da177e4 | 1178 | /* |
06386bbf | 1179 | * If region is not in-sync queue the bio. |
1da177e4 | 1180 | */ |
06386bbf JB |
1181 | if (!r || (r == -EWOULDBLOCK)) { |
1182 | if (rw == READA) | |
1183 | return -EWOULDBLOCK; | |
1da177e4 | 1184 | |
1da177e4 | 1185 | queue_bio(ms, bio, rw); |
d2a7ad29 | 1186 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
1187 | } |
1188 | ||
06386bbf JB |
1189 | /* |
1190 | * The region is in-sync and we can perform reads directly. | |
1191 | * Store enough information so we can retry if it fails. | |
1192 | */ | |
4f024f37 | 1193 | m = choose_mirror(ms, bio->bi_iter.bi_sector); |
06386bbf | 1194 | if (unlikely(!m)) |
1da177e4 LT |
1195 | return -EIO; |
1196 | ||
89c7cd89 | 1197 | dm_bio_record(&bio_record->details, bio); |
89c7cd89 | 1198 | bio_record->m = m; |
06386bbf JB |
1199 | |
1200 | map_bio(m, bio); | |
1201 | ||
d2a7ad29 | 1202 | return DM_MAPIO_REMAPPED; |
1da177e4 LT |
1203 | } |
1204 | ||
7de3ee57 | 1205 | static int mirror_end_io(struct dm_target *ti, struct bio *bio, int error) |
1da177e4 LT |
1206 | { |
1207 | int rw = bio_rw(bio); | |
1208 | struct mirror_set *ms = (struct mirror_set *) ti->private; | |
06386bbf JB |
1209 | struct mirror *m = NULL; |
1210 | struct dm_bio_details *bd = NULL; | |
0045d61b MP |
1211 | struct dm_raid1_bio_record *bio_record = |
1212 | dm_per_bio_data(bio, sizeof(struct dm_raid1_bio_record)); | |
1da177e4 LT |
1213 | |
1214 | /* | |
1215 | * We need to dec pending if this was a write. | |
1216 | */ | |
06386bbf | 1217 | if (rw == WRITE) { |
751f188d | 1218 | if (!(bio->bi_rw & (REQ_FLUSH | REQ_DISCARD))) |
0045d61b | 1219 | dm_rh_dec(ms->rh, bio_record->write_region); |
06386bbf JB |
1220 | return error; |
1221 | } | |
1da177e4 | 1222 | |
06386bbf JB |
1223 | if (error == -EOPNOTSUPP) |
1224 | goto out; | |
1225 | ||
7b6d91da | 1226 | if ((error == -EWOULDBLOCK) && (bio->bi_rw & REQ_RAHEAD)) |
06386bbf JB |
1227 | goto out; |
1228 | ||
1229 | if (unlikely(error)) { | |
0045d61b | 1230 | if (!bio_record->details.bi_bdev) { |
06386bbf JB |
1231 | /* |
1232 | * There wasn't enough memory to record necessary | |
1233 | * information for a retry or there was no other | |
1234 | * mirror in-sync. | |
1235 | */ | |
e03f1a84 | 1236 | DMERR_LIMIT("Mirror read failed."); |
06386bbf JB |
1237 | return -EIO; |
1238 | } | |
e03f1a84 | 1239 | |
89c7cd89 | 1240 | m = bio_record->m; |
e03f1a84 | 1241 | |
06386bbf JB |
1242 | DMERR("Mirror read failed from %s. Trying alternative device.", |
1243 | m->dev->name); | |
1244 | ||
06386bbf JB |
1245 | fail_mirror(m, DM_RAID1_READ_ERROR); |
1246 | ||
1247 | /* | |
1248 | * A failed read is requeued for another attempt using an intact | |
1249 | * mirror. | |
1250 | */ | |
1251 | if (default_ok(m) || mirror_available(ms, bio)) { | |
89c7cd89 | 1252 | bd = &bio_record->details; |
06386bbf JB |
1253 | |
1254 | dm_bio_restore(bd, bio); | |
0045d61b | 1255 | bio_record->details.bi_bdev = NULL; |
f3a44fe0 MP |
1256 | |
1257 | atomic_inc(&bio->bi_remaining); | |
1258 | ||
06386bbf | 1259 | queue_bio(ms, bio, rw); |
19cbbc60 | 1260 | return DM_ENDIO_INCOMPLETE; |
06386bbf JB |
1261 | } |
1262 | DMERR("All replicated volumes dead, failing I/O"); | |
1263 | } | |
1264 | ||
1265 | out: | |
0045d61b | 1266 | bio_record->details.bi_bdev = NULL; |
06386bbf JB |
1267 | |
1268 | return error; | |
1da177e4 LT |
1269 | } |
1270 | ||
b80aa7a0 | 1271 | static void mirror_presuspend(struct dm_target *ti) |
1da177e4 LT |
1272 | { |
1273 | struct mirror_set *ms = (struct mirror_set *) ti->private; | |
1f965b19 | 1274 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
1da177e4 | 1275 | |
04788507 MP |
1276 | struct bio_list holds; |
1277 | struct bio *bio; | |
1278 | ||
b80aa7a0 JB |
1279 | atomic_set(&ms->suspend, 1); |
1280 | ||
f0703040 TY |
1281 | /* |
1282 | * Process bios in the hold list to start recovery waiting | |
1283 | * for bios in the hold list. After the process, no bio has | |
1284 | * a chance to be added in the hold list because ms->suspend | |
1285 | * is set. | |
1286 | */ | |
1287 | spin_lock_irq(&ms->lock); | |
1288 | holds = ms->holds; | |
1289 | bio_list_init(&ms->holds); | |
1290 | spin_unlock_irq(&ms->lock); | |
1291 | ||
1292 | while ((bio = bio_list_pop(&holds))) | |
1293 | hold_bio(ms, bio); | |
1294 | ||
b80aa7a0 JB |
1295 | /* |
1296 | * We must finish up all the work that we've | |
1297 | * generated (i.e. recovery work). | |
1298 | */ | |
1f965b19 | 1299 | dm_rh_stop_recovery(ms->rh); |
33184048 | 1300 | |
33184048 | 1301 | wait_event(_kmirrord_recovery_stopped, |
1f965b19 | 1302 | !dm_rh_recovery_in_flight(ms->rh)); |
33184048 | 1303 | |
b80aa7a0 JB |
1304 | if (log->type->presuspend && log->type->presuspend(log)) |
1305 | /* FIXME: need better error handling */ | |
1306 | DMWARN("log presuspend failed"); | |
1307 | ||
1308 | /* | |
1309 | * Now that recovery is complete/stopped and the | |
1310 | * delayed bios are queued, we need to wait for | |
1311 | * the worker thread to complete. This way, | |
1312 | * we know that all of our I/O has been pushed. | |
1313 | */ | |
1314 | flush_workqueue(ms->kmirrord_wq); | |
1315 | } | |
1316 | ||
1317 | static void mirror_postsuspend(struct dm_target *ti) | |
1318 | { | |
1319 | struct mirror_set *ms = ti->private; | |
1f965b19 | 1320 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
b80aa7a0 | 1321 | |
6b3df0d7 | 1322 | if (log->type->postsuspend && log->type->postsuspend(log)) |
1da177e4 | 1323 | /* FIXME: need better error handling */ |
b80aa7a0 | 1324 | DMWARN("log postsuspend failed"); |
1da177e4 LT |
1325 | } |
1326 | ||
1327 | static void mirror_resume(struct dm_target *ti) | |
1328 | { | |
b80aa7a0 | 1329 | struct mirror_set *ms = ti->private; |
1f965b19 | 1330 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
b80aa7a0 JB |
1331 | |
1332 | atomic_set(&ms->suspend, 0); | |
1da177e4 LT |
1333 | if (log->type->resume && log->type->resume(log)) |
1334 | /* FIXME: need better error handling */ | |
1335 | DMWARN("log resume failed"); | |
1f965b19 | 1336 | dm_rh_start_recovery(ms->rh); |
1da177e4 LT |
1337 | } |
1338 | ||
af195ac8 JB |
1339 | /* |
1340 | * device_status_char | |
1341 | * @m: mirror device/leg we want the status of | |
1342 | * | |
1343 | * We return one character representing the most severe error | |
1344 | * we have encountered. | |
1345 | * A => Alive - No failures | |
1346 | * D => Dead - A write failure occurred leaving mirror out-of-sync | |
1347 | * S => Sync - A sychronization failure occurred, mirror out-of-sync | |
1348 | * R => Read - A read failure occurred, mirror data unaffected | |
1349 | * | |
1350 | * Returns: <char> | |
1351 | */ | |
1352 | static char device_status_char(struct mirror *m) | |
1353 | { | |
1354 | if (!atomic_read(&(m->error_count))) | |
1355 | return 'A'; | |
1356 | ||
64b30c46 MP |
1357 | return (test_bit(DM_RAID1_FLUSH_ERROR, &(m->error_type))) ? 'F' : |
1358 | (test_bit(DM_RAID1_WRITE_ERROR, &(m->error_type))) ? 'D' : | |
af195ac8 JB |
1359 | (test_bit(DM_RAID1_SYNC_ERROR, &(m->error_type))) ? 'S' : |
1360 | (test_bit(DM_RAID1_READ_ERROR, &(m->error_type))) ? 'R' : 'U'; | |
1361 | } | |
1362 | ||
1363 | ||
fd7c092e MP |
1364 | static void mirror_status(struct dm_target *ti, status_type_t type, |
1365 | unsigned status_flags, char *result, unsigned maxlen) | |
1da177e4 | 1366 | { |
315dcc22 | 1367 | unsigned int m, sz = 0; |
1da177e4 | 1368 | struct mirror_set *ms = (struct mirror_set *) ti->private; |
1f965b19 | 1369 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
af195ac8 | 1370 | char buffer[ms->nr_mirrors + 1]; |
1da177e4 | 1371 | |
1da177e4 LT |
1372 | switch (type) { |
1373 | case STATUSTYPE_INFO: | |
1374 | DMEMIT("%d ", ms->nr_mirrors); | |
af195ac8 | 1375 | for (m = 0; m < ms->nr_mirrors; m++) { |
1da177e4 | 1376 | DMEMIT("%s ", ms->mirror[m].dev->name); |
af195ac8 JB |
1377 | buffer[m] = device_status_char(&(ms->mirror[m])); |
1378 | } | |
1379 | buffer[m] = '\0'; | |
1da177e4 | 1380 | |
af195ac8 | 1381 | DMEMIT("%llu/%llu 1 %s ", |
1f965b19 | 1382 | (unsigned long long)log->type->get_sync_count(log), |
af195ac8 | 1383 | (unsigned long long)ms->nr_regions, buffer); |
315dcc22 | 1384 | |
1f965b19 | 1385 | sz += log->type->status(log, type, result+sz, maxlen-sz); |
315dcc22 | 1386 | |
1da177e4 LT |
1387 | break; |
1388 | ||
1389 | case STATUSTYPE_TABLE: | |
1f965b19 | 1390 | sz = log->type->status(log, type, result, maxlen); |
315dcc22 | 1391 | |
e52b8f6d | 1392 | DMEMIT("%d", ms->nr_mirrors); |
1da177e4 | 1393 | for (m = 0; m < ms->nr_mirrors; m++) |
e52b8f6d | 1394 | DMEMIT(" %s %llu", ms->mirror[m].dev->name, |
b80aa7a0 | 1395 | (unsigned long long)ms->mirror[m].offset); |
a8e6afa2 JB |
1396 | |
1397 | if (ms->features & DM_RAID1_HANDLE_ERRORS) | |
1398 | DMEMIT(" 1 handle_errors"); | |
1da177e4 | 1399 | } |
1da177e4 LT |
1400 | } |
1401 | ||
af4874e0 MS |
1402 | static int mirror_iterate_devices(struct dm_target *ti, |
1403 | iterate_devices_callout_fn fn, void *data) | |
1404 | { | |
1405 | struct mirror_set *ms = ti->private; | |
1406 | int ret = 0; | |
1407 | unsigned i; | |
1408 | ||
1409 | for (i = 0; !ret && i < ms->nr_mirrors; i++) | |
1410 | ret = fn(ti, ms->mirror[i].dev, | |
5dea271b | 1411 | ms->mirror[i].offset, ti->len, data); |
af4874e0 MS |
1412 | |
1413 | return ret; | |
1414 | } | |
1415 | ||
1da177e4 LT |
1416 | static struct target_type mirror_target = { |
1417 | .name = "mirror", | |
fd7c092e | 1418 | .version = {1, 13, 2}, |
1da177e4 LT |
1419 | .module = THIS_MODULE, |
1420 | .ctr = mirror_ctr, | |
1421 | .dtr = mirror_dtr, | |
1422 | .map = mirror_map, | |
1423 | .end_io = mirror_end_io, | |
b80aa7a0 | 1424 | .presuspend = mirror_presuspend, |
1da177e4 LT |
1425 | .postsuspend = mirror_postsuspend, |
1426 | .resume = mirror_resume, | |
1427 | .status = mirror_status, | |
af4874e0 | 1428 | .iterate_devices = mirror_iterate_devices, |
1da177e4 LT |
1429 | }; |
1430 | ||
1431 | static int __init dm_mirror_init(void) | |
1432 | { | |
1433 | int r; | |
1434 | ||
1da177e4 | 1435 | r = dm_register_target(&mirror_target); |
95f8fac8 | 1436 | if (r < 0) { |
0cd33124 | 1437 | DMERR("Failed to register mirror target"); |
95f8fac8 MP |
1438 | goto bad_target; |
1439 | } | |
1440 | ||
1441 | return 0; | |
1da177e4 | 1442 | |
95f8fac8 | 1443 | bad_target: |
1da177e4 LT |
1444 | return r; |
1445 | } | |
1446 | ||
1447 | static void __exit dm_mirror_exit(void) | |
1448 | { | |
10d3bd09 | 1449 | dm_unregister_target(&mirror_target); |
1da177e4 LT |
1450 | } |
1451 | ||
1452 | /* Module hooks */ | |
1453 | module_init(dm_mirror_init); | |
1454 | module_exit(dm_mirror_exit); | |
1455 | ||
1456 | MODULE_DESCRIPTION(DM_NAME " mirror target"); | |
1457 | MODULE_AUTHOR("Joe Thornber"); | |
1458 | MODULE_LICENSE("GPL"); |