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Commit | Line | Data |
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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. */ | |
88be163a | 25 | #define DM_IO_PAGES 64 |
1f965b19 | 26 | #define DM_KCOPYD_PAGES 64 |
72d94861 | 27 | |
a8e6afa2 | 28 | #define DM_RAID1_HANDLE_ERRORS 0x01 |
f44db678 | 29 | #define errors_handled(p) ((p)->features & DM_RAID1_HANDLE_ERRORS) |
a8e6afa2 | 30 | |
33184048 | 31 | static DECLARE_WAIT_QUEUE_HEAD(_kmirrord_recovery_stopped); |
1da177e4 | 32 | |
e4c8b3ba NB |
33 | /*----------------------------------------------------------------- |
34 | * Mirror set structures. | |
35 | *---------------------------------------------------------------*/ | |
72f4b314 JB |
36 | enum dm_raid1_error { |
37 | DM_RAID1_WRITE_ERROR, | |
38 | DM_RAID1_SYNC_ERROR, | |
39 | DM_RAID1_READ_ERROR | |
40 | }; | |
41 | ||
e4c8b3ba | 42 | struct mirror { |
aa5617c5 | 43 | struct mirror_set *ms; |
e4c8b3ba | 44 | atomic_t error_count; |
39ed7adb | 45 | unsigned long error_type; |
e4c8b3ba NB |
46 | struct dm_dev *dev; |
47 | sector_t offset; | |
48 | }; | |
49 | ||
50 | struct mirror_set { | |
51 | struct dm_target *ti; | |
52 | struct list_head list; | |
1f965b19 | 53 | |
a8e6afa2 | 54 | uint64_t features; |
e4c8b3ba | 55 | |
72f4b314 | 56 | spinlock_t lock; /* protects the lists */ |
e4c8b3ba NB |
57 | struct bio_list reads; |
58 | struct bio_list writes; | |
72f4b314 | 59 | struct bio_list failures; |
e4c8b3ba | 60 | |
1f965b19 HM |
61 | struct dm_region_hash *rh; |
62 | struct dm_kcopyd_client *kcopyd_client; | |
88be163a | 63 | struct dm_io_client *io_client; |
06386bbf | 64 | mempool_t *read_record_pool; |
88be163a | 65 | |
e4c8b3ba NB |
66 | /* recovery */ |
67 | region_t nr_regions; | |
68 | int in_sync; | |
fc1ff958 | 69 | int log_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 | ||
06386bbf JB |
141 | #define MIN_READ_RECORDS 20 |
142 | struct dm_raid1_read_record { | |
143 | struct mirror *m; | |
144 | struct dm_bio_details details; | |
145 | }; | |
146 | ||
95f8fac8 MP |
147 | static struct kmem_cache *_dm_raid1_read_record_cache; |
148 | ||
1da177e4 LT |
149 | /* |
150 | * Every mirror should look like this one. | |
151 | */ | |
152 | #define DEFAULT_MIRROR 0 | |
153 | ||
154 | /* | |
06386bbf JB |
155 | * This is yucky. We squirrel the mirror struct away inside |
156 | * bi_next for read/write buffers. This is safe since the bh | |
1da177e4 LT |
157 | * doesn't get submitted to the lower levels of block layer. |
158 | */ | |
06386bbf | 159 | static struct mirror *bio_get_m(struct bio *bio) |
1da177e4 | 160 | { |
06386bbf | 161 | return (struct mirror *) bio->bi_next; |
1da177e4 LT |
162 | } |
163 | ||
06386bbf | 164 | static void bio_set_m(struct bio *bio, struct mirror *m) |
1da177e4 | 165 | { |
06386bbf | 166 | bio->bi_next = (struct bio *) m; |
1da177e4 LT |
167 | } |
168 | ||
72f4b314 JB |
169 | static struct mirror *get_default_mirror(struct mirror_set *ms) |
170 | { | |
171 | return &ms->mirror[atomic_read(&ms->default_mirror)]; | |
172 | } | |
173 | ||
174 | static void set_default_mirror(struct mirror *m) | |
175 | { | |
176 | struct mirror_set *ms = m->ms; | |
177 | struct mirror *m0 = &(ms->mirror[0]); | |
178 | ||
179 | atomic_set(&ms->default_mirror, m - m0); | |
180 | } | |
181 | ||
182 | /* fail_mirror | |
183 | * @m: mirror device to fail | |
184 | * @error_type: one of the enum's, DM_RAID1_*_ERROR | |
185 | * | |
186 | * If errors are being handled, record the type of | |
187 | * error encountered for this device. If this type | |
188 | * of error has already been recorded, we can return; | |
189 | * otherwise, we must signal userspace by triggering | |
190 | * an event. Additionally, if the device is the | |
191 | * primary device, we must choose a new primary, but | |
192 | * only if the mirror is in-sync. | |
193 | * | |
194 | * This function must not block. | |
195 | */ | |
196 | static void fail_mirror(struct mirror *m, enum dm_raid1_error error_type) | |
197 | { | |
198 | struct mirror_set *ms = m->ms; | |
199 | struct mirror *new; | |
200 | ||
72f4b314 JB |
201 | /* |
202 | * error_count is used for nothing more than a | |
203 | * simple way to tell if a device has encountered | |
204 | * errors. | |
205 | */ | |
206 | atomic_inc(&m->error_count); | |
207 | ||
208 | if (test_and_set_bit(error_type, &m->error_type)) | |
209 | return; | |
210 | ||
d460c65a JB |
211 | if (!errors_handled(ms)) |
212 | return; | |
213 | ||
72f4b314 JB |
214 | if (m != get_default_mirror(ms)) |
215 | goto out; | |
216 | ||
217 | if (!ms->in_sync) { | |
218 | /* | |
219 | * Better to issue requests to same failing device | |
220 | * than to risk returning corrupt data. | |
221 | */ | |
222 | DMERR("Primary mirror (%s) failed while out-of-sync: " | |
223 | "Reads may fail.", m->dev->name); | |
224 | goto out; | |
225 | } | |
226 | ||
227 | for (new = ms->mirror; new < ms->mirror + ms->nr_mirrors; new++) | |
228 | if (!atomic_read(&new->error_count)) { | |
229 | set_default_mirror(new); | |
230 | break; | |
231 | } | |
232 | ||
233 | if (unlikely(new == ms->mirror + ms->nr_mirrors)) | |
234 | DMWARN("All sides of mirror have failed."); | |
235 | ||
236 | out: | |
237 | schedule_work(&ms->trigger_event); | |
238 | } | |
239 | ||
1da177e4 LT |
240 | /*----------------------------------------------------------------- |
241 | * Recovery. | |
242 | * | |
243 | * When a mirror is first activated we may find that some regions | |
244 | * are in the no-sync state. We have to recover these by | |
245 | * recopying from the default mirror to all the others. | |
246 | *---------------------------------------------------------------*/ | |
4cdc1d1f | 247 | static void recovery_complete(int read_err, unsigned long write_err, |
1da177e4 LT |
248 | void *context) |
249 | { | |
1f965b19 HM |
250 | struct dm_region *reg = context; |
251 | struct mirror_set *ms = dm_rh_region_context(reg); | |
8f0205b7 | 252 | int m, bit = 0; |
1da177e4 | 253 | |
8f0205b7 | 254 | if (read_err) { |
f44db678 JB |
255 | /* Read error means the failure of default mirror. */ |
256 | DMERR_LIMIT("Unable to read primary mirror during recovery"); | |
8f0205b7 JB |
257 | fail_mirror(get_default_mirror(ms), DM_RAID1_SYNC_ERROR); |
258 | } | |
f44db678 | 259 | |
8f0205b7 | 260 | if (write_err) { |
4cdc1d1f | 261 | DMERR_LIMIT("Write error during recovery (error = 0x%lx)", |
f44db678 | 262 | write_err); |
8f0205b7 JB |
263 | /* |
264 | * Bits correspond to devices (excluding default mirror). | |
265 | * The default mirror cannot change during recovery. | |
266 | */ | |
267 | for (m = 0; m < ms->nr_mirrors; m++) { | |
268 | if (&ms->mirror[m] == get_default_mirror(ms)) | |
269 | continue; | |
270 | if (test_bit(bit, &write_err)) | |
271 | fail_mirror(ms->mirror + m, | |
272 | DM_RAID1_SYNC_ERROR); | |
273 | bit++; | |
274 | } | |
275 | } | |
f44db678 | 276 | |
1f965b19 | 277 | dm_rh_recovery_end(reg, !(read_err || write_err)); |
1da177e4 LT |
278 | } |
279 | ||
1f965b19 | 280 | static int recover(struct mirror_set *ms, struct dm_region *reg) |
1da177e4 LT |
281 | { |
282 | int r; | |
1f965b19 | 283 | unsigned i; |
eb69aca5 | 284 | struct dm_io_region from, to[DM_KCOPYD_MAX_REGIONS], *dest; |
1da177e4 LT |
285 | struct mirror *m; |
286 | unsigned long flags = 0; | |
1f965b19 HM |
287 | region_t key = dm_rh_get_region_key(reg); |
288 | sector_t region_size = dm_rh_get_region_size(ms->rh); | |
1da177e4 LT |
289 | |
290 | /* fill in the source */ | |
72f4b314 | 291 | m = get_default_mirror(ms); |
1da177e4 | 292 | from.bdev = m->dev->bdev; |
1f965b19 HM |
293 | from.sector = m->offset + dm_rh_region_to_sector(ms->rh, key); |
294 | if (key == (ms->nr_regions - 1)) { | |
1da177e4 LT |
295 | /* |
296 | * The final region may be smaller than | |
297 | * region_size. | |
298 | */ | |
1f965b19 | 299 | from.count = ms->ti->len & (region_size - 1); |
1da177e4 | 300 | if (!from.count) |
1f965b19 | 301 | from.count = region_size; |
1da177e4 | 302 | } else |
1f965b19 | 303 | from.count = region_size; |
1da177e4 LT |
304 | |
305 | /* fill in the destinations */ | |
306 | for (i = 0, dest = to; i < ms->nr_mirrors; i++) { | |
72f4b314 | 307 | if (&ms->mirror[i] == get_default_mirror(ms)) |
1da177e4 LT |
308 | continue; |
309 | ||
310 | m = ms->mirror + i; | |
311 | dest->bdev = m->dev->bdev; | |
1f965b19 | 312 | dest->sector = m->offset + dm_rh_region_to_sector(ms->rh, key); |
1da177e4 LT |
313 | dest->count = from.count; |
314 | dest++; | |
315 | } | |
316 | ||
317 | /* hand to kcopyd */ | |
f7c83e2e JB |
318 | if (!errors_handled(ms)) |
319 | set_bit(DM_KCOPYD_IGNORE_ERROR, &flags); | |
320 | ||
eb69aca5 HM |
321 | r = dm_kcopyd_copy(ms->kcopyd_client, &from, ms->nr_mirrors - 1, to, |
322 | flags, recovery_complete, reg); | |
1da177e4 LT |
323 | |
324 | return r; | |
325 | } | |
326 | ||
327 | static void do_recovery(struct mirror_set *ms) | |
328 | { | |
1f965b19 HM |
329 | struct dm_region *reg; |
330 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); | |
1da177e4 | 331 | int r; |
1da177e4 LT |
332 | |
333 | /* | |
334 | * Start quiescing some regions. | |
335 | */ | |
1f965b19 | 336 | dm_rh_recovery_prepare(ms->rh); |
1da177e4 LT |
337 | |
338 | /* | |
339 | * Copy any already quiesced regions. | |
340 | */ | |
1f965b19 | 341 | while ((reg = dm_rh_recovery_start(ms->rh))) { |
1da177e4 LT |
342 | r = recover(ms, reg); |
343 | if (r) | |
1f965b19 | 344 | dm_rh_recovery_end(reg, 0); |
1da177e4 LT |
345 | } |
346 | ||
347 | /* | |
348 | * Update the in sync flag. | |
349 | */ | |
350 | if (!ms->in_sync && | |
351 | (log->type->get_sync_count(log) == ms->nr_regions)) { | |
352 | /* the sync is complete */ | |
353 | dm_table_event(ms->ti->table); | |
354 | ms->in_sync = 1; | |
355 | } | |
356 | } | |
357 | ||
358 | /*----------------------------------------------------------------- | |
359 | * Reads | |
360 | *---------------------------------------------------------------*/ | |
361 | static struct mirror *choose_mirror(struct mirror_set *ms, sector_t sector) | |
362 | { | |
06386bbf JB |
363 | struct mirror *m = get_default_mirror(ms); |
364 | ||
365 | do { | |
366 | if (likely(!atomic_read(&m->error_count))) | |
367 | return m; | |
368 | ||
369 | if (m-- == ms->mirror) | |
370 | m += ms->nr_mirrors; | |
371 | } while (m != get_default_mirror(ms)); | |
372 | ||
373 | return NULL; | |
374 | } | |
375 | ||
376 | static int default_ok(struct mirror *m) | |
377 | { | |
378 | struct mirror *default_mirror = get_default_mirror(m->ms); | |
379 | ||
380 | return !atomic_read(&default_mirror->error_count); | |
381 | } | |
382 | ||
383 | static int mirror_available(struct mirror_set *ms, struct bio *bio) | |
384 | { | |
1f965b19 HM |
385 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
386 | region_t region = dm_rh_bio_to_region(ms->rh, bio); | |
06386bbf | 387 | |
1f965b19 | 388 | if (log->type->in_sync(log, region, 0)) |
06386bbf JB |
389 | return choose_mirror(ms, bio->bi_sector) ? 1 : 0; |
390 | ||
391 | return 0; | |
1da177e4 LT |
392 | } |
393 | ||
394 | /* | |
395 | * remap a buffer to a particular mirror. | |
396 | */ | |
06386bbf JB |
397 | static sector_t map_sector(struct mirror *m, struct bio *bio) |
398 | { | |
4184153f MP |
399 | if (unlikely(!bio->bi_size)) |
400 | return 0; | |
06386bbf JB |
401 | return m->offset + (bio->bi_sector - m->ms->ti->begin); |
402 | } | |
403 | ||
404 | static void map_bio(struct mirror *m, struct bio *bio) | |
1da177e4 LT |
405 | { |
406 | bio->bi_bdev = m->dev->bdev; | |
06386bbf JB |
407 | bio->bi_sector = map_sector(m, bio); |
408 | } | |
409 | ||
22a1ceb1 | 410 | static void map_region(struct dm_io_region *io, struct mirror *m, |
06386bbf JB |
411 | struct bio *bio) |
412 | { | |
413 | io->bdev = m->dev->bdev; | |
414 | io->sector = map_sector(m, bio); | |
415 | io->count = bio->bi_size >> 9; | |
416 | } | |
417 | ||
418 | /*----------------------------------------------------------------- | |
419 | * Reads | |
420 | *---------------------------------------------------------------*/ | |
421 | static void read_callback(unsigned long error, void *context) | |
422 | { | |
423 | struct bio *bio = context; | |
424 | struct mirror *m; | |
425 | ||
426 | m = bio_get_m(bio); | |
427 | bio_set_m(bio, NULL); | |
428 | ||
429 | if (likely(!error)) { | |
430 | bio_endio(bio, 0); | |
431 | return; | |
432 | } | |
433 | ||
434 | fail_mirror(m, DM_RAID1_READ_ERROR); | |
435 | ||
436 | if (likely(default_ok(m)) || mirror_available(m->ms, bio)) { | |
437 | DMWARN_LIMIT("Read failure on mirror device %s. " | |
438 | "Trying alternative device.", | |
439 | m->dev->name); | |
440 | queue_bio(m->ms, bio, bio_rw(bio)); | |
441 | return; | |
442 | } | |
443 | ||
444 | DMERR_LIMIT("Read failure on mirror device %s. Failing I/O.", | |
445 | m->dev->name); | |
446 | bio_endio(bio, -EIO); | |
447 | } | |
448 | ||
449 | /* Asynchronous read. */ | |
450 | static void read_async_bio(struct mirror *m, struct bio *bio) | |
451 | { | |
22a1ceb1 | 452 | struct dm_io_region io; |
06386bbf JB |
453 | struct dm_io_request io_req = { |
454 | .bi_rw = READ, | |
455 | .mem.type = DM_IO_BVEC, | |
456 | .mem.ptr.bvec = bio->bi_io_vec + bio->bi_idx, | |
457 | .notify.fn = read_callback, | |
458 | .notify.context = bio, | |
459 | .client = m->ms->io_client, | |
460 | }; | |
461 | ||
462 | map_region(&io, m, bio); | |
463 | bio_set_m(bio, m); | |
1f965b19 HM |
464 | BUG_ON(dm_io(&io_req, 1, &io, NULL)); |
465 | } | |
466 | ||
467 | static inline int region_in_sync(struct mirror_set *ms, region_t region, | |
468 | int may_block) | |
469 | { | |
470 | int state = dm_rh_get_state(ms->rh, region, may_block); | |
471 | return state == DM_RH_CLEAN || state == DM_RH_DIRTY; | |
1da177e4 LT |
472 | } |
473 | ||
474 | static void do_reads(struct mirror_set *ms, struct bio_list *reads) | |
475 | { | |
476 | region_t region; | |
477 | struct bio *bio; | |
478 | struct mirror *m; | |
479 | ||
480 | while ((bio = bio_list_pop(reads))) { | |
1f965b19 | 481 | region = dm_rh_bio_to_region(ms->rh, bio); |
06386bbf | 482 | m = get_default_mirror(ms); |
1da177e4 LT |
483 | |
484 | /* | |
485 | * We can only read balance if the region is in sync. | |
486 | */ | |
1f965b19 | 487 | if (likely(region_in_sync(ms, region, 1))) |
1da177e4 | 488 | m = choose_mirror(ms, bio->bi_sector); |
06386bbf JB |
489 | else if (m && atomic_read(&m->error_count)) |
490 | m = NULL; | |
1da177e4 | 491 | |
06386bbf JB |
492 | if (likely(m)) |
493 | read_async_bio(m, bio); | |
494 | else | |
495 | bio_endio(bio, -EIO); | |
1da177e4 LT |
496 | } |
497 | } | |
498 | ||
499 | /*----------------------------------------------------------------- | |
500 | * Writes. | |
501 | * | |
502 | * We do different things with the write io depending on the | |
503 | * state of the region that it's in: | |
504 | * | |
505 | * SYNC: increment pending, use kcopyd to write to *all* mirrors | |
506 | * RECOVERING: delay the io until recovery completes | |
507 | * NOSYNC: increment pending, just write to the default mirror | |
508 | *---------------------------------------------------------------*/ | |
72f4b314 | 509 | |
72f4b314 | 510 | |
1da177e4 LT |
511 | static void write_callback(unsigned long error, void *context) |
512 | { | |
72f4b314 | 513 | unsigned i, ret = 0; |
1da177e4 LT |
514 | struct bio *bio = (struct bio *) context; |
515 | struct mirror_set *ms; | |
72f4b314 JB |
516 | int uptodate = 0; |
517 | int should_wake = 0; | |
518 | unsigned long flags; | |
1da177e4 | 519 | |
06386bbf JB |
520 | ms = bio_get_m(bio)->ms; |
521 | bio_set_m(bio, NULL); | |
1da177e4 LT |
522 | |
523 | /* | |
524 | * NOTE: We don't decrement the pending count here, | |
525 | * instead it is done by the targets endio function. | |
526 | * This way we handle both writes to SYNC and NOSYNC | |
527 | * regions with the same code. | |
528 | */ | |
72f4b314 JB |
529 | if (likely(!error)) |
530 | goto out; | |
1da177e4 | 531 | |
72f4b314 JB |
532 | for (i = 0; i < ms->nr_mirrors; i++) |
533 | if (test_bit(i, &error)) | |
534 | fail_mirror(ms->mirror + i, DM_RAID1_WRITE_ERROR); | |
535 | else | |
536 | uptodate = 1; | |
537 | ||
538 | if (unlikely(!uptodate)) { | |
539 | DMERR("All replicated volumes dead, failing I/O"); | |
540 | /* None of the writes succeeded, fail the I/O. */ | |
541 | ret = -EIO; | |
542 | } else if (errors_handled(ms)) { | |
1da177e4 | 543 | /* |
72f4b314 JB |
544 | * Need to raise event. Since raising |
545 | * events can block, we need to do it in | |
546 | * the main thread. | |
1da177e4 | 547 | */ |
72f4b314 JB |
548 | spin_lock_irqsave(&ms->lock, flags); |
549 | if (!ms->failures.head) | |
550 | should_wake = 1; | |
551 | bio_list_add(&ms->failures, bio); | |
552 | spin_unlock_irqrestore(&ms->lock, flags); | |
553 | if (should_wake) | |
1f965b19 | 554 | wakeup_mirrord(ms); |
72f4b314 | 555 | return; |
1da177e4 | 556 | } |
72f4b314 JB |
557 | out: |
558 | bio_endio(bio, ret); | |
1da177e4 LT |
559 | } |
560 | ||
561 | static void do_write(struct mirror_set *ms, struct bio *bio) | |
562 | { | |
563 | unsigned int i; | |
22a1ceb1 | 564 | struct dm_io_region io[ms->nr_mirrors], *dest = io; |
1da177e4 | 565 | struct mirror *m; |
88be163a | 566 | struct dm_io_request io_req = { |
4184153f | 567 | .bi_rw = WRITE | (bio->bi_rw & WRITE_BARRIER), |
88be163a MB |
568 | .mem.type = DM_IO_BVEC, |
569 | .mem.ptr.bvec = bio->bi_io_vec + bio->bi_idx, | |
570 | .notify.fn = write_callback, | |
571 | .notify.context = bio, | |
572 | .client = ms->io_client, | |
573 | }; | |
1da177e4 | 574 | |
06386bbf JB |
575 | for (i = 0, m = ms->mirror; i < ms->nr_mirrors; i++, m++) |
576 | map_region(dest++, m, bio); | |
1da177e4 | 577 | |
06386bbf JB |
578 | /* |
579 | * Use default mirror because we only need it to retrieve the reference | |
580 | * to the mirror set in write_callback(). | |
581 | */ | |
582 | bio_set_m(bio, get_default_mirror(ms)); | |
88be163a | 583 | |
1f965b19 | 584 | BUG_ON(dm_io(&io_req, ms->nr_mirrors, io, NULL)); |
1da177e4 LT |
585 | } |
586 | ||
587 | static void do_writes(struct mirror_set *ms, struct bio_list *writes) | |
588 | { | |
589 | int state; | |
590 | struct bio *bio; | |
591 | struct bio_list sync, nosync, recover, *this_list = NULL; | |
7513c2a7 JB |
592 | struct bio_list requeue; |
593 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); | |
594 | region_t region; | |
1da177e4 LT |
595 | |
596 | if (!writes->head) | |
597 | return; | |
598 | ||
599 | /* | |
600 | * Classify each write. | |
601 | */ | |
602 | bio_list_init(&sync); | |
603 | bio_list_init(&nosync); | |
604 | bio_list_init(&recover); | |
7513c2a7 | 605 | bio_list_init(&requeue); |
1da177e4 LT |
606 | |
607 | while ((bio = bio_list_pop(writes))) { | |
4184153f MP |
608 | if (unlikely(bio_empty_barrier(bio))) { |
609 | bio_list_add(&sync, bio); | |
610 | continue; | |
611 | } | |
612 | ||
7513c2a7 JB |
613 | region = dm_rh_bio_to_region(ms->rh, bio); |
614 | ||
615 | if (log->type->is_remote_recovering && | |
616 | log->type->is_remote_recovering(log, region)) { | |
617 | bio_list_add(&requeue, bio); | |
618 | continue; | |
619 | } | |
620 | ||
621 | state = dm_rh_get_state(ms->rh, region, 1); | |
1da177e4 | 622 | switch (state) { |
1f965b19 HM |
623 | case DM_RH_CLEAN: |
624 | case DM_RH_DIRTY: | |
1da177e4 LT |
625 | this_list = &sync; |
626 | break; | |
627 | ||
1f965b19 | 628 | case DM_RH_NOSYNC: |
1da177e4 LT |
629 | this_list = &nosync; |
630 | break; | |
631 | ||
1f965b19 | 632 | case DM_RH_RECOVERING: |
1da177e4 LT |
633 | this_list = &recover; |
634 | break; | |
635 | } | |
636 | ||
637 | bio_list_add(this_list, bio); | |
638 | } | |
639 | ||
7513c2a7 JB |
640 | /* |
641 | * Add bios that are delayed due to remote recovery | |
642 | * back on to the write queue | |
643 | */ | |
644 | if (unlikely(requeue.head)) { | |
645 | spin_lock_irq(&ms->lock); | |
646 | bio_list_merge(&ms->writes, &requeue); | |
647 | spin_unlock_irq(&ms->lock); | |
69885683 | 648 | delayed_wake(ms); |
7513c2a7 JB |
649 | } |
650 | ||
1da177e4 LT |
651 | /* |
652 | * Increment the pending counts for any regions that will | |
653 | * be written to (writes to recover regions are going to | |
654 | * be delayed). | |
655 | */ | |
1f965b19 HM |
656 | dm_rh_inc_pending(ms->rh, &sync); |
657 | dm_rh_inc_pending(ms->rh, &nosync); | |
d2b69864 JB |
658 | |
659 | /* | |
660 | * If the flush fails on a previous call and succeeds here, | |
661 | * we must not reset the log_failure variable. We need | |
662 | * userspace interaction to do that. | |
663 | */ | |
664 | ms->log_failure = dm_rh_flush(ms->rh) ? 1 : ms->log_failure; | |
1da177e4 LT |
665 | |
666 | /* | |
667 | * Dispatch io. | |
668 | */ | |
b80aa7a0 JB |
669 | if (unlikely(ms->log_failure)) { |
670 | spin_lock_irq(&ms->lock); | |
671 | bio_list_merge(&ms->failures, &sync); | |
672 | spin_unlock_irq(&ms->lock); | |
1f965b19 | 673 | wakeup_mirrord(ms); |
b80aa7a0 | 674 | } else |
fc1ff958 | 675 | while ((bio = bio_list_pop(&sync))) |
b80aa7a0 | 676 | do_write(ms, bio); |
1da177e4 LT |
677 | |
678 | while ((bio = bio_list_pop(&recover))) | |
1f965b19 | 679 | dm_rh_delay(ms->rh, bio); |
1da177e4 LT |
680 | |
681 | while ((bio = bio_list_pop(&nosync))) { | |
06386bbf | 682 | map_bio(get_default_mirror(ms), bio); |
1da177e4 LT |
683 | generic_make_request(bio); |
684 | } | |
685 | } | |
686 | ||
72f4b314 JB |
687 | static void do_failures(struct mirror_set *ms, struct bio_list *failures) |
688 | { | |
689 | struct bio *bio; | |
690 | ||
691 | if (!failures->head) | |
692 | return; | |
693 | ||
b80aa7a0 | 694 | if (!ms->log_failure) { |
b34578a4 | 695 | while ((bio = bio_list_pop(failures))) { |
1f965b19 HM |
696 | ms->in_sync = 0; |
697 | dm_rh_mark_nosync(ms->rh, bio, bio->bi_size, 0); | |
b34578a4 | 698 | } |
b80aa7a0 JB |
699 | return; |
700 | } | |
701 | ||
702 | /* | |
703 | * If the log has failed, unattempted writes are being | |
704 | * put on the failures list. We can't issue those writes | |
705 | * until a log has been marked, so we must store them. | |
706 | * | |
707 | * If a 'noflush' suspend is in progress, we can requeue | |
708 | * the I/O's to the core. This give userspace a chance | |
709 | * to reconfigure the mirror, at which point the core | |
710 | * will reissue the writes. If the 'noflush' flag is | |
711 | * not set, we have no choice but to return errors. | |
712 | * | |
713 | * Some writes on the failures list may have been | |
714 | * submitted before the log failure and represent a | |
715 | * failure to write to one of the devices. It is ok | |
716 | * for us to treat them the same and requeue them | |
717 | * as well. | |
718 | */ | |
719 | if (dm_noflush_suspending(ms->ti)) { | |
720 | while ((bio = bio_list_pop(failures))) | |
721 | bio_endio(bio, DM_ENDIO_REQUEUE); | |
722 | return; | |
723 | } | |
724 | ||
725 | if (atomic_read(&ms->suspend)) { | |
726 | while ((bio = bio_list_pop(failures))) | |
727 | bio_endio(bio, -EIO); | |
728 | return; | |
729 | } | |
730 | ||
731 | spin_lock_irq(&ms->lock); | |
732 | bio_list_merge(&ms->failures, failures); | |
733 | spin_unlock_irq(&ms->lock); | |
734 | ||
a2aebe03 | 735 | delayed_wake(ms); |
72f4b314 JB |
736 | } |
737 | ||
738 | static void trigger_event(struct work_struct *work) | |
739 | { | |
740 | struct mirror_set *ms = | |
741 | container_of(work, struct mirror_set, trigger_event); | |
742 | ||
743 | dm_table_event(ms->ti->table); | |
744 | } | |
745 | ||
1da177e4 LT |
746 | /*----------------------------------------------------------------- |
747 | * kmirrord | |
748 | *---------------------------------------------------------------*/ | |
a2aebe03 | 749 | static void do_mirror(struct work_struct *work) |
1da177e4 | 750 | { |
1f965b19 HM |
751 | struct mirror_set *ms = container_of(work, struct mirror_set, |
752 | kmirrord_work); | |
72f4b314 JB |
753 | struct bio_list reads, writes, failures; |
754 | unsigned long flags; | |
1da177e4 | 755 | |
72f4b314 | 756 | spin_lock_irqsave(&ms->lock, flags); |
1da177e4 LT |
757 | reads = ms->reads; |
758 | writes = ms->writes; | |
72f4b314 | 759 | failures = ms->failures; |
1da177e4 LT |
760 | bio_list_init(&ms->reads); |
761 | bio_list_init(&ms->writes); | |
72f4b314 JB |
762 | bio_list_init(&ms->failures); |
763 | spin_unlock_irqrestore(&ms->lock, flags); | |
1da177e4 | 764 | |
1f965b19 | 765 | dm_rh_update_states(ms->rh, errors_handled(ms)); |
1da177e4 LT |
766 | do_recovery(ms); |
767 | do_reads(ms, &reads); | |
768 | do_writes(ms, &writes); | |
72f4b314 | 769 | do_failures(ms, &failures); |
7ff14a36 MP |
770 | |
771 | dm_table_unplug_all(ms->ti->table); | |
1da177e4 LT |
772 | } |
773 | ||
1da177e4 LT |
774 | /*----------------------------------------------------------------- |
775 | * Target functions | |
776 | *---------------------------------------------------------------*/ | |
777 | static struct mirror_set *alloc_context(unsigned int nr_mirrors, | |
778 | uint32_t region_size, | |
779 | struct dm_target *ti, | |
416cd17b | 780 | struct dm_dirty_log *dl) |
1da177e4 LT |
781 | { |
782 | size_t len; | |
783 | struct mirror_set *ms = NULL; | |
784 | ||
1da177e4 LT |
785 | len = sizeof(*ms) + (sizeof(ms->mirror[0]) * nr_mirrors); |
786 | ||
dd00cc48 | 787 | ms = kzalloc(len, GFP_KERNEL); |
1da177e4 | 788 | if (!ms) { |
72d94861 | 789 | ti->error = "Cannot allocate mirror context"; |
1da177e4 LT |
790 | return NULL; |
791 | } | |
792 | ||
1da177e4 LT |
793 | spin_lock_init(&ms->lock); |
794 | ||
795 | ms->ti = ti; | |
796 | ms->nr_mirrors = nr_mirrors; | |
797 | ms->nr_regions = dm_sector_div_up(ti->len, region_size); | |
798 | ms->in_sync = 0; | |
b80aa7a0 JB |
799 | ms->log_failure = 0; |
800 | atomic_set(&ms->suspend, 0); | |
72f4b314 | 801 | atomic_set(&ms->default_mirror, DEFAULT_MIRROR); |
1da177e4 | 802 | |
95f8fac8 MP |
803 | ms->read_record_pool = mempool_create_slab_pool(MIN_READ_RECORDS, |
804 | _dm_raid1_read_record_cache); | |
805 | ||
06386bbf JB |
806 | if (!ms->read_record_pool) { |
807 | ti->error = "Error creating mirror read_record_pool"; | |
808 | kfree(ms); | |
809 | return NULL; | |
810 | } | |
811 | ||
88be163a MB |
812 | ms->io_client = dm_io_client_create(DM_IO_PAGES); |
813 | if (IS_ERR(ms->io_client)) { | |
814 | ti->error = "Error creating dm_io client"; | |
06386bbf | 815 | mempool_destroy(ms->read_record_pool); |
88be163a MB |
816 | kfree(ms); |
817 | return NULL; | |
818 | } | |
819 | ||
1f965b19 HM |
820 | ms->rh = dm_region_hash_create(ms, dispatch_bios, wakeup_mirrord, |
821 | wakeup_all_recovery_waiters, | |
822 | ms->ti->begin, MAX_RECOVERY, | |
823 | dl, region_size, ms->nr_regions); | |
824 | if (IS_ERR(ms->rh)) { | |
72d94861 | 825 | ti->error = "Error creating dirty region hash"; |
a72cf737 | 826 | dm_io_client_destroy(ms->io_client); |
06386bbf | 827 | mempool_destroy(ms->read_record_pool); |
1da177e4 LT |
828 | kfree(ms); |
829 | return NULL; | |
830 | } | |
831 | ||
832 | return ms; | |
833 | } | |
834 | ||
835 | static void free_context(struct mirror_set *ms, struct dm_target *ti, | |
836 | unsigned int m) | |
837 | { | |
838 | while (m--) | |
839 | dm_put_device(ti, ms->mirror[m].dev); | |
840 | ||
88be163a | 841 | dm_io_client_destroy(ms->io_client); |
1f965b19 | 842 | dm_region_hash_destroy(ms->rh); |
06386bbf | 843 | mempool_destroy(ms->read_record_pool); |
1da177e4 LT |
844 | kfree(ms); |
845 | } | |
846 | ||
1da177e4 LT |
847 | static int get_mirror(struct mirror_set *ms, struct dm_target *ti, |
848 | unsigned int mirror, char **argv) | |
849 | { | |
4ee218cd | 850 | unsigned long long offset; |
1da177e4 | 851 | |
4ee218cd | 852 | if (sscanf(argv[1], "%llu", &offset) != 1) { |
72d94861 | 853 | ti->error = "Invalid offset"; |
1da177e4 LT |
854 | return -EINVAL; |
855 | } | |
856 | ||
857 | if (dm_get_device(ti, argv[0], offset, ti->len, | |
858 | dm_table_get_mode(ti->table), | |
859 | &ms->mirror[mirror].dev)) { | |
72d94861 | 860 | ti->error = "Device lookup failure"; |
1da177e4 LT |
861 | return -ENXIO; |
862 | } | |
863 | ||
aa5617c5 | 864 | ms->mirror[mirror].ms = ms; |
72f4b314 JB |
865 | atomic_set(&(ms->mirror[mirror].error_count), 0); |
866 | ms->mirror[mirror].error_type = 0; | |
1da177e4 LT |
867 | ms->mirror[mirror].offset = offset; |
868 | ||
869 | return 0; | |
870 | } | |
871 | ||
1da177e4 LT |
872 | /* |
873 | * Create dirty log: log_type #log_params <log_params> | |
874 | */ | |
416cd17b | 875 | static struct dm_dirty_log *create_dirty_log(struct dm_target *ti, |
1f965b19 HM |
876 | unsigned argc, char **argv, |
877 | unsigned *args_used) | |
1da177e4 | 878 | { |
1f965b19 | 879 | unsigned param_count; |
416cd17b | 880 | struct dm_dirty_log *dl; |
1da177e4 LT |
881 | |
882 | if (argc < 2) { | |
72d94861 | 883 | ti->error = "Insufficient mirror log arguments"; |
1da177e4 LT |
884 | return NULL; |
885 | } | |
886 | ||
887 | if (sscanf(argv[1], "%u", ¶m_count) != 1) { | |
72d94861 | 888 | ti->error = "Invalid mirror log argument count"; |
1da177e4 LT |
889 | return NULL; |
890 | } | |
891 | ||
892 | *args_used = 2 + param_count; | |
893 | ||
894 | if (argc < *args_used) { | |
72d94861 | 895 | ti->error = "Insufficient mirror log arguments"; |
1da177e4 LT |
896 | return NULL; |
897 | } | |
898 | ||
87a8f240 | 899 | dl = dm_dirty_log_create(argv[0], ti, NULL, param_count, argv + 2); |
1da177e4 | 900 | if (!dl) { |
72d94861 | 901 | ti->error = "Error creating mirror dirty log"; |
1da177e4 LT |
902 | return NULL; |
903 | } | |
904 | ||
1da177e4 LT |
905 | return dl; |
906 | } | |
907 | ||
a8e6afa2 JB |
908 | static int parse_features(struct mirror_set *ms, unsigned argc, char **argv, |
909 | unsigned *args_used) | |
910 | { | |
911 | unsigned num_features; | |
912 | struct dm_target *ti = ms->ti; | |
913 | ||
914 | *args_used = 0; | |
915 | ||
916 | if (!argc) | |
917 | return 0; | |
918 | ||
919 | if (sscanf(argv[0], "%u", &num_features) != 1) { | |
920 | ti->error = "Invalid number of features"; | |
921 | return -EINVAL; | |
922 | } | |
923 | ||
924 | argc--; | |
925 | argv++; | |
926 | (*args_used)++; | |
927 | ||
928 | if (num_features > argc) { | |
929 | ti->error = "Not enough arguments to support feature count"; | |
930 | return -EINVAL; | |
931 | } | |
932 | ||
933 | if (!strcmp("handle_errors", argv[0])) | |
934 | ms->features |= DM_RAID1_HANDLE_ERRORS; | |
935 | else { | |
936 | ti->error = "Unrecognised feature requested"; | |
937 | return -EINVAL; | |
938 | } | |
939 | ||
940 | (*args_used)++; | |
941 | ||
942 | return 0; | |
943 | } | |
944 | ||
1da177e4 LT |
945 | /* |
946 | * Construct a mirror mapping: | |
947 | * | |
948 | * log_type #log_params <log_params> | |
949 | * #mirrors [mirror_path offset]{2,} | |
a8e6afa2 | 950 | * [#features <features>] |
1da177e4 LT |
951 | * |
952 | * log_type is "core" or "disk" | |
953 | * #log_params is between 1 and 3 | |
a8e6afa2 JB |
954 | * |
955 | * If present, features must be "handle_errors". | |
1da177e4 | 956 | */ |
1da177e4 LT |
957 | static int mirror_ctr(struct dm_target *ti, unsigned int argc, char **argv) |
958 | { | |
959 | int r; | |
960 | unsigned int nr_mirrors, m, args_used; | |
961 | struct mirror_set *ms; | |
416cd17b | 962 | struct dm_dirty_log *dl; |
1da177e4 LT |
963 | |
964 | dl = create_dirty_log(ti, argc, argv, &args_used); | |
965 | if (!dl) | |
966 | return -EINVAL; | |
967 | ||
968 | argv += args_used; | |
969 | argc -= args_used; | |
970 | ||
971 | if (!argc || sscanf(argv[0], "%u", &nr_mirrors) != 1 || | |
eb69aca5 | 972 | nr_mirrors < 2 || nr_mirrors > DM_KCOPYD_MAX_REGIONS + 1) { |
72d94861 | 973 | ti->error = "Invalid number of mirrors"; |
416cd17b | 974 | dm_dirty_log_destroy(dl); |
1da177e4 LT |
975 | return -EINVAL; |
976 | } | |
977 | ||
978 | argv++, argc--; | |
979 | ||
a8e6afa2 JB |
980 | if (argc < nr_mirrors * 2) { |
981 | ti->error = "Too few mirror arguments"; | |
416cd17b | 982 | dm_dirty_log_destroy(dl); |
1da177e4 LT |
983 | return -EINVAL; |
984 | } | |
985 | ||
986 | ms = alloc_context(nr_mirrors, dl->type->get_region_size(dl), ti, dl); | |
987 | if (!ms) { | |
416cd17b | 988 | dm_dirty_log_destroy(dl); |
1da177e4 LT |
989 | return -ENOMEM; |
990 | } | |
991 | ||
992 | /* Get the mirror parameter sets */ | |
993 | for (m = 0; m < nr_mirrors; m++) { | |
994 | r = get_mirror(ms, ti, m, argv); | |
995 | if (r) { | |
996 | free_context(ms, ti, m); | |
997 | return r; | |
998 | } | |
999 | argv += 2; | |
1000 | argc -= 2; | |
1001 | } | |
1002 | ||
1003 | ti->private = ms; | |
1f965b19 | 1004 | ti->split_io = dm_rh_get_region_size(ms->rh); |
4184153f | 1005 | ti->num_flush_requests = 1; |
1da177e4 | 1006 | |
6ad36fe2 HS |
1007 | ms->kmirrord_wq = create_singlethread_workqueue("kmirrord"); |
1008 | if (!ms->kmirrord_wq) { | |
1009 | DMERR("couldn't start kmirrord"); | |
a72cf737 DM |
1010 | r = -ENOMEM; |
1011 | goto err_free_context; | |
6ad36fe2 HS |
1012 | } |
1013 | INIT_WORK(&ms->kmirrord_work, do_mirror); | |
a2aebe03 MP |
1014 | init_timer(&ms->timer); |
1015 | ms->timer_pending = 0; | |
72f4b314 | 1016 | INIT_WORK(&ms->trigger_event, trigger_event); |
6ad36fe2 | 1017 | |
a8e6afa2 | 1018 | r = parse_features(ms, argc, argv, &args_used); |
a72cf737 DM |
1019 | if (r) |
1020 | goto err_destroy_wq; | |
a8e6afa2 JB |
1021 | |
1022 | argv += args_used; | |
1023 | argc -= args_used; | |
1024 | ||
f44db678 JB |
1025 | /* |
1026 | * Any read-balancing addition depends on the | |
1027 | * DM_RAID1_HANDLE_ERRORS flag being present. | |
1028 | * This is because the decision to balance depends | |
1029 | * on the sync state of a region. If the above | |
1030 | * flag is not present, we ignore errors; and | |
1031 | * the sync state may be inaccurate. | |
1032 | */ | |
1033 | ||
a8e6afa2 JB |
1034 | if (argc) { |
1035 | ti->error = "Too many mirror arguments"; | |
a72cf737 DM |
1036 | r = -EINVAL; |
1037 | goto err_destroy_wq; | |
a8e6afa2 JB |
1038 | } |
1039 | ||
1f965b19 | 1040 | r = dm_kcopyd_client_create(DM_KCOPYD_PAGES, &ms->kcopyd_client); |
a72cf737 DM |
1041 | if (r) |
1042 | goto err_destroy_wq; | |
1da177e4 | 1043 | |
1f965b19 | 1044 | wakeup_mirrord(ms); |
1da177e4 | 1045 | return 0; |
a72cf737 DM |
1046 | |
1047 | err_destroy_wq: | |
1048 | destroy_workqueue(ms->kmirrord_wq); | |
1049 | err_free_context: | |
1050 | free_context(ms, ti, ms->nr_mirrors); | |
1051 | return r; | |
1da177e4 LT |
1052 | } |
1053 | ||
1054 | static void mirror_dtr(struct dm_target *ti) | |
1055 | { | |
1056 | struct mirror_set *ms = (struct mirror_set *) ti->private; | |
1057 | ||
a2aebe03 | 1058 | del_timer_sync(&ms->timer); |
6ad36fe2 | 1059 | flush_workqueue(ms->kmirrord_wq); |
18776c73 | 1060 | flush_scheduled_work(); |
eb69aca5 | 1061 | dm_kcopyd_client_destroy(ms->kcopyd_client); |
6ad36fe2 | 1062 | destroy_workqueue(ms->kmirrord_wq); |
1da177e4 LT |
1063 | free_context(ms, ti, ms->nr_mirrors); |
1064 | } | |
1065 | ||
1da177e4 LT |
1066 | /* |
1067 | * Mirror mapping function | |
1068 | */ | |
1069 | static int mirror_map(struct dm_target *ti, struct bio *bio, | |
1070 | union map_info *map_context) | |
1071 | { | |
1072 | int r, rw = bio_rw(bio); | |
1073 | struct mirror *m; | |
1074 | struct mirror_set *ms = ti->private; | |
06386bbf | 1075 | struct dm_raid1_read_record *read_record = NULL; |
1f965b19 | 1076 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
1da177e4 LT |
1077 | |
1078 | if (rw == WRITE) { | |
06386bbf | 1079 | /* Save region for mirror_end_io() handler */ |
1f965b19 | 1080 | map_context->ll = dm_rh_bio_to_region(ms->rh, bio); |
1da177e4 | 1081 | queue_bio(ms, bio, rw); |
d2a7ad29 | 1082 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
1083 | } |
1084 | ||
1f965b19 | 1085 | r = log->type->in_sync(log, dm_rh_bio_to_region(ms->rh, bio), 0); |
1da177e4 LT |
1086 | if (r < 0 && r != -EWOULDBLOCK) |
1087 | return r; | |
1088 | ||
1da177e4 | 1089 | /* |
06386bbf | 1090 | * If region is not in-sync queue the bio. |
1da177e4 | 1091 | */ |
06386bbf JB |
1092 | if (!r || (r == -EWOULDBLOCK)) { |
1093 | if (rw == READA) | |
1094 | return -EWOULDBLOCK; | |
1da177e4 | 1095 | |
1da177e4 | 1096 | queue_bio(ms, bio, rw); |
d2a7ad29 | 1097 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
1098 | } |
1099 | ||
06386bbf JB |
1100 | /* |
1101 | * The region is in-sync and we can perform reads directly. | |
1102 | * Store enough information so we can retry if it fails. | |
1103 | */ | |
1da177e4 | 1104 | m = choose_mirror(ms, bio->bi_sector); |
06386bbf | 1105 | if (unlikely(!m)) |
1da177e4 LT |
1106 | return -EIO; |
1107 | ||
06386bbf JB |
1108 | read_record = mempool_alloc(ms->read_record_pool, GFP_NOIO); |
1109 | if (likely(read_record)) { | |
1110 | dm_bio_record(&read_record->details, bio); | |
1111 | map_context->ptr = read_record; | |
1112 | read_record->m = m; | |
1113 | } | |
1114 | ||
1115 | map_bio(m, bio); | |
1116 | ||
d2a7ad29 | 1117 | return DM_MAPIO_REMAPPED; |
1da177e4 LT |
1118 | } |
1119 | ||
1120 | static int mirror_end_io(struct dm_target *ti, struct bio *bio, | |
1121 | int error, union map_info *map_context) | |
1122 | { | |
1123 | int rw = bio_rw(bio); | |
1124 | struct mirror_set *ms = (struct mirror_set *) ti->private; | |
06386bbf JB |
1125 | struct mirror *m = NULL; |
1126 | struct dm_bio_details *bd = NULL; | |
1127 | struct dm_raid1_read_record *read_record = map_context->ptr; | |
1da177e4 LT |
1128 | |
1129 | /* | |
1130 | * We need to dec pending if this was a write. | |
1131 | */ | |
06386bbf | 1132 | if (rw == WRITE) { |
4184153f MP |
1133 | if (likely(!bio_empty_barrier(bio))) |
1134 | dm_rh_dec(ms->rh, map_context->ll); | |
06386bbf JB |
1135 | return error; |
1136 | } | |
1da177e4 | 1137 | |
06386bbf JB |
1138 | if (error == -EOPNOTSUPP) |
1139 | goto out; | |
1140 | ||
1f98a13f | 1141 | if ((error == -EWOULDBLOCK) && bio_rw_flagged(bio, BIO_RW_AHEAD)) |
06386bbf JB |
1142 | goto out; |
1143 | ||
1144 | if (unlikely(error)) { | |
1145 | if (!read_record) { | |
1146 | /* | |
1147 | * There wasn't enough memory to record necessary | |
1148 | * information for a retry or there was no other | |
1149 | * mirror in-sync. | |
1150 | */ | |
e03f1a84 | 1151 | DMERR_LIMIT("Mirror read failed."); |
06386bbf JB |
1152 | return -EIO; |
1153 | } | |
e03f1a84 AB |
1154 | |
1155 | m = read_record->m; | |
1156 | ||
06386bbf JB |
1157 | DMERR("Mirror read failed from %s. Trying alternative device.", |
1158 | m->dev->name); | |
1159 | ||
06386bbf JB |
1160 | fail_mirror(m, DM_RAID1_READ_ERROR); |
1161 | ||
1162 | /* | |
1163 | * A failed read is requeued for another attempt using an intact | |
1164 | * mirror. | |
1165 | */ | |
1166 | if (default_ok(m) || mirror_available(ms, bio)) { | |
1167 | bd = &read_record->details; | |
1168 | ||
1169 | dm_bio_restore(bd, bio); | |
1170 | mempool_free(read_record, ms->read_record_pool); | |
1171 | map_context->ptr = NULL; | |
1172 | queue_bio(ms, bio, rw); | |
1173 | return 1; | |
1174 | } | |
1175 | DMERR("All replicated volumes dead, failing I/O"); | |
1176 | } | |
1177 | ||
1178 | out: | |
1179 | if (read_record) { | |
1180 | mempool_free(read_record, ms->read_record_pool); | |
1181 | map_context->ptr = NULL; | |
1182 | } | |
1183 | ||
1184 | return error; | |
1da177e4 LT |
1185 | } |
1186 | ||
b80aa7a0 | 1187 | static void mirror_presuspend(struct dm_target *ti) |
1da177e4 LT |
1188 | { |
1189 | struct mirror_set *ms = (struct mirror_set *) ti->private; | |
1f965b19 | 1190 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
1da177e4 | 1191 | |
b80aa7a0 JB |
1192 | atomic_set(&ms->suspend, 1); |
1193 | ||
1194 | /* | |
1195 | * We must finish up all the work that we've | |
1196 | * generated (i.e. recovery work). | |
1197 | */ | |
1f965b19 | 1198 | dm_rh_stop_recovery(ms->rh); |
33184048 | 1199 | |
33184048 | 1200 | wait_event(_kmirrord_recovery_stopped, |
1f965b19 | 1201 | !dm_rh_recovery_in_flight(ms->rh)); |
33184048 | 1202 | |
b80aa7a0 JB |
1203 | if (log->type->presuspend && log->type->presuspend(log)) |
1204 | /* FIXME: need better error handling */ | |
1205 | DMWARN("log presuspend failed"); | |
1206 | ||
1207 | /* | |
1208 | * Now that recovery is complete/stopped and the | |
1209 | * delayed bios are queued, we need to wait for | |
1210 | * the worker thread to complete. This way, | |
1211 | * we know that all of our I/O has been pushed. | |
1212 | */ | |
1213 | flush_workqueue(ms->kmirrord_wq); | |
1214 | } | |
1215 | ||
1216 | static void mirror_postsuspend(struct dm_target *ti) | |
1217 | { | |
1218 | struct mirror_set *ms = ti->private; | |
1f965b19 | 1219 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
b80aa7a0 | 1220 | |
6b3df0d7 | 1221 | if (log->type->postsuspend && log->type->postsuspend(log)) |
1da177e4 | 1222 | /* FIXME: need better error handling */ |
b80aa7a0 | 1223 | DMWARN("log postsuspend failed"); |
1da177e4 LT |
1224 | } |
1225 | ||
1226 | static void mirror_resume(struct dm_target *ti) | |
1227 | { | |
b80aa7a0 | 1228 | struct mirror_set *ms = ti->private; |
1f965b19 | 1229 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
b80aa7a0 JB |
1230 | |
1231 | atomic_set(&ms->suspend, 0); | |
1da177e4 LT |
1232 | if (log->type->resume && log->type->resume(log)) |
1233 | /* FIXME: need better error handling */ | |
1234 | DMWARN("log resume failed"); | |
1f965b19 | 1235 | dm_rh_start_recovery(ms->rh); |
1da177e4 LT |
1236 | } |
1237 | ||
af195ac8 JB |
1238 | /* |
1239 | * device_status_char | |
1240 | * @m: mirror device/leg we want the status of | |
1241 | * | |
1242 | * We return one character representing the most severe error | |
1243 | * we have encountered. | |
1244 | * A => Alive - No failures | |
1245 | * D => Dead - A write failure occurred leaving mirror out-of-sync | |
1246 | * S => Sync - A sychronization failure occurred, mirror out-of-sync | |
1247 | * R => Read - A read failure occurred, mirror data unaffected | |
1248 | * | |
1249 | * Returns: <char> | |
1250 | */ | |
1251 | static char device_status_char(struct mirror *m) | |
1252 | { | |
1253 | if (!atomic_read(&(m->error_count))) | |
1254 | return 'A'; | |
1255 | ||
1256 | return (test_bit(DM_RAID1_WRITE_ERROR, &(m->error_type))) ? 'D' : | |
1257 | (test_bit(DM_RAID1_SYNC_ERROR, &(m->error_type))) ? 'S' : | |
1258 | (test_bit(DM_RAID1_READ_ERROR, &(m->error_type))) ? 'R' : 'U'; | |
1259 | } | |
1260 | ||
1261 | ||
1da177e4 LT |
1262 | static int mirror_status(struct dm_target *ti, status_type_t type, |
1263 | char *result, unsigned int maxlen) | |
1264 | { | |
315dcc22 | 1265 | unsigned int m, sz = 0; |
1da177e4 | 1266 | struct mirror_set *ms = (struct mirror_set *) ti->private; |
1f965b19 | 1267 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
af195ac8 | 1268 | char buffer[ms->nr_mirrors + 1]; |
1da177e4 | 1269 | |
1da177e4 LT |
1270 | switch (type) { |
1271 | case STATUSTYPE_INFO: | |
1272 | DMEMIT("%d ", ms->nr_mirrors); | |
af195ac8 | 1273 | for (m = 0; m < ms->nr_mirrors; m++) { |
1da177e4 | 1274 | DMEMIT("%s ", ms->mirror[m].dev->name); |
af195ac8 JB |
1275 | buffer[m] = device_status_char(&(ms->mirror[m])); |
1276 | } | |
1277 | buffer[m] = '\0'; | |
1da177e4 | 1278 | |
af195ac8 | 1279 | DMEMIT("%llu/%llu 1 %s ", |
1f965b19 | 1280 | (unsigned long long)log->type->get_sync_count(log), |
af195ac8 | 1281 | (unsigned long long)ms->nr_regions, buffer); |
315dcc22 | 1282 | |
1f965b19 | 1283 | sz += log->type->status(log, type, result+sz, maxlen-sz); |
315dcc22 | 1284 | |
1da177e4 LT |
1285 | break; |
1286 | ||
1287 | case STATUSTYPE_TABLE: | |
1f965b19 | 1288 | sz = log->type->status(log, type, result, maxlen); |
315dcc22 | 1289 | |
e52b8f6d | 1290 | DMEMIT("%d", ms->nr_mirrors); |
1da177e4 | 1291 | for (m = 0; m < ms->nr_mirrors; m++) |
e52b8f6d | 1292 | DMEMIT(" %s %llu", ms->mirror[m].dev->name, |
b80aa7a0 | 1293 | (unsigned long long)ms->mirror[m].offset); |
a8e6afa2 JB |
1294 | |
1295 | if (ms->features & DM_RAID1_HANDLE_ERRORS) | |
1296 | DMEMIT(" 1 handle_errors"); | |
1da177e4 LT |
1297 | } |
1298 | ||
1299 | return 0; | |
1300 | } | |
1301 | ||
af4874e0 MS |
1302 | static int mirror_iterate_devices(struct dm_target *ti, |
1303 | iterate_devices_callout_fn fn, void *data) | |
1304 | { | |
1305 | struct mirror_set *ms = ti->private; | |
1306 | int ret = 0; | |
1307 | unsigned i; | |
1308 | ||
1309 | for (i = 0; !ret && i < ms->nr_mirrors; i++) | |
1310 | ret = fn(ti, ms->mirror[i].dev, | |
5dea271b | 1311 | ms->mirror[i].offset, ti->len, data); |
af4874e0 MS |
1312 | |
1313 | return ret; | |
1314 | } | |
1315 | ||
1da177e4 LT |
1316 | static struct target_type mirror_target = { |
1317 | .name = "mirror", | |
af4874e0 | 1318 | .version = {1, 12, 0}, |
1da177e4 LT |
1319 | .module = THIS_MODULE, |
1320 | .ctr = mirror_ctr, | |
1321 | .dtr = mirror_dtr, | |
1322 | .map = mirror_map, | |
1323 | .end_io = mirror_end_io, | |
b80aa7a0 | 1324 | .presuspend = mirror_presuspend, |
1da177e4 LT |
1325 | .postsuspend = mirror_postsuspend, |
1326 | .resume = mirror_resume, | |
1327 | .status = mirror_status, | |
af4874e0 | 1328 | .iterate_devices = mirror_iterate_devices, |
1da177e4 LT |
1329 | }; |
1330 | ||
1331 | static int __init dm_mirror_init(void) | |
1332 | { | |
1333 | int r; | |
1334 | ||
95f8fac8 MP |
1335 | _dm_raid1_read_record_cache = KMEM_CACHE(dm_raid1_read_record, 0); |
1336 | if (!_dm_raid1_read_record_cache) { | |
1337 | DMERR("Can't allocate dm_raid1_read_record cache"); | |
1338 | r = -ENOMEM; | |
1339 | goto bad_cache; | |
1340 | } | |
1341 | ||
1da177e4 | 1342 | r = dm_register_target(&mirror_target); |
95f8fac8 | 1343 | if (r < 0) { |
0cd33124 | 1344 | DMERR("Failed to register mirror target"); |
95f8fac8 MP |
1345 | goto bad_target; |
1346 | } | |
1347 | ||
1348 | return 0; | |
1da177e4 | 1349 | |
95f8fac8 MP |
1350 | bad_target: |
1351 | kmem_cache_destroy(_dm_raid1_read_record_cache); | |
1352 | bad_cache: | |
1da177e4 LT |
1353 | return r; |
1354 | } | |
1355 | ||
1356 | static void __exit dm_mirror_exit(void) | |
1357 | { | |
10d3bd09 | 1358 | dm_unregister_target(&mirror_target); |
95f8fac8 | 1359 | kmem_cache_destroy(_dm_raid1_read_record_cache); |
1da177e4 LT |
1360 | } |
1361 | ||
1362 | /* Module hooks */ | |
1363 | module_init(dm_mirror_init); | |
1364 | module_exit(dm_mirror_exit); | |
1365 | ||
1366 | MODULE_DESCRIPTION(DM_NAME " mirror target"); | |
1367 | MODULE_AUTHOR("Joe Thornber"); | |
1368 | MODULE_LICENSE("GPL"); |