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. */ | |
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, | |
64b30c46 | 38 | DM_RAID1_FLUSH_ERROR, |
72f4b314 JB |
39 | DM_RAID1_SYNC_ERROR, |
40 | DM_RAID1_READ_ERROR | |
41 | }; | |
42 | ||
e4c8b3ba | 43 | struct mirror { |
aa5617c5 | 44 | struct mirror_set *ms; |
e4c8b3ba | 45 | atomic_t error_count; |
39ed7adb | 46 | unsigned long error_type; |
e4c8b3ba NB |
47 | struct dm_dev *dev; |
48 | sector_t offset; | |
49 | }; | |
50 | ||
51 | struct mirror_set { | |
52 | struct dm_target *ti; | |
53 | struct list_head list; | |
1f965b19 | 54 | |
a8e6afa2 | 55 | uint64_t features; |
e4c8b3ba | 56 | |
72f4b314 | 57 | spinlock_t lock; /* protects the lists */ |
e4c8b3ba NB |
58 | struct bio_list reads; |
59 | struct bio_list writes; | |
72f4b314 | 60 | struct bio_list failures; |
04788507 | 61 | struct bio_list holds; /* bios are waiting until suspend */ |
e4c8b3ba | 62 | |
1f965b19 HM |
63 | struct dm_region_hash *rh; |
64 | struct dm_kcopyd_client *kcopyd_client; | |
88be163a | 65 | struct dm_io_client *io_client; |
06386bbf | 66 | mempool_t *read_record_pool; |
88be163a | 67 | |
e4c8b3ba NB |
68 | /* recovery */ |
69 | region_t nr_regions; | |
70 | int in_sync; | |
fc1ff958 | 71 | int log_failure; |
b80aa7a0 | 72 | atomic_t suspend; |
e4c8b3ba | 73 | |
72f4b314 | 74 | atomic_t default_mirror; /* Default mirror */ |
e4c8b3ba | 75 | |
6ad36fe2 HS |
76 | struct workqueue_struct *kmirrord_wq; |
77 | struct work_struct kmirrord_work; | |
a2aebe03 MP |
78 | struct timer_list timer; |
79 | unsigned long timer_pending; | |
80 | ||
72f4b314 | 81 | struct work_struct trigger_event; |
6ad36fe2 | 82 | |
1f965b19 | 83 | unsigned nr_mirrors; |
e4c8b3ba NB |
84 | struct mirror mirror[0]; |
85 | }; | |
86 | ||
1f965b19 | 87 | static void wakeup_mirrord(void *context) |
1da177e4 | 88 | { |
1f965b19 | 89 | struct mirror_set *ms = context; |
1da177e4 | 90 | |
6ad36fe2 HS |
91 | queue_work(ms->kmirrord_wq, &ms->kmirrord_work); |
92 | } | |
93 | ||
a2aebe03 MP |
94 | static void delayed_wake_fn(unsigned long data) |
95 | { | |
96 | struct mirror_set *ms = (struct mirror_set *) data; | |
97 | ||
98 | clear_bit(0, &ms->timer_pending); | |
1f965b19 | 99 | wakeup_mirrord(ms); |
a2aebe03 MP |
100 | } |
101 | ||
102 | static void delayed_wake(struct mirror_set *ms) | |
103 | { | |
104 | if (test_and_set_bit(0, &ms->timer_pending)) | |
105 | return; | |
106 | ||
107 | ms->timer.expires = jiffies + HZ / 5; | |
108 | ms->timer.data = (unsigned long) ms; | |
109 | ms->timer.function = delayed_wake_fn; | |
110 | add_timer(&ms->timer); | |
111 | } | |
112 | ||
1f965b19 | 113 | static void wakeup_all_recovery_waiters(void *context) |
1da177e4 | 114 | { |
1f965b19 | 115 | wake_up_all(&_kmirrord_recovery_stopped); |
1da177e4 LT |
116 | } |
117 | ||
1f965b19 | 118 | static void queue_bio(struct mirror_set *ms, struct bio *bio, int rw) |
1da177e4 LT |
119 | { |
120 | unsigned long flags; | |
1da177e4 | 121 | int should_wake = 0; |
1f965b19 | 122 | struct bio_list *bl; |
1da177e4 | 123 | |
1f965b19 HM |
124 | bl = (rw == WRITE) ? &ms->writes : &ms->reads; |
125 | spin_lock_irqsave(&ms->lock, flags); | |
126 | should_wake = !(bl->head); | |
127 | bio_list_add(bl, bio); | |
128 | spin_unlock_irqrestore(&ms->lock, flags); | |
1da177e4 LT |
129 | |
130 | if (should_wake) | |
1f965b19 | 131 | wakeup_mirrord(ms); |
1da177e4 LT |
132 | } |
133 | ||
1f965b19 | 134 | static void dispatch_bios(void *context, struct bio_list *bio_list) |
1da177e4 | 135 | { |
1f965b19 HM |
136 | struct mirror_set *ms = context; |
137 | struct bio *bio; | |
1da177e4 | 138 | |
1f965b19 HM |
139 | while ((bio = bio_list_pop(bio_list))) |
140 | queue_bio(ms, bio, WRITE); | |
1da177e4 LT |
141 | } |
142 | ||
06386bbf JB |
143 | #define MIN_READ_RECORDS 20 |
144 | struct dm_raid1_read_record { | |
145 | struct mirror *m; | |
146 | struct dm_bio_details details; | |
147 | }; | |
148 | ||
95f8fac8 MP |
149 | static struct kmem_cache *_dm_raid1_read_record_cache; |
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 | ||
184 | /* fail_mirror | |
185 | * @m: mirror device to fail | |
186 | * @error_type: one of the enum's, DM_RAID1_*_ERROR | |
187 | * | |
188 | * If errors are being handled, record the type of | |
189 | * error encountered for this device. If this type | |
190 | * of error has already been recorded, we can return; | |
191 | * otherwise, we must signal userspace by triggering | |
192 | * an event. Additionally, if the device is the | |
193 | * primary device, we must choose a new primary, but | |
194 | * only if the mirror is in-sync. | |
195 | * | |
196 | * This function must not block. | |
197 | */ | |
198 | static void fail_mirror(struct mirror *m, enum dm_raid1_error error_type) | |
199 | { | |
200 | struct mirror_set *ms = m->ms; | |
201 | struct mirror *new; | |
202 | ||
72f4b314 JB |
203 | /* |
204 | * error_count is used for nothing more than a | |
205 | * simple way to tell if a device has encountered | |
206 | * errors. | |
207 | */ | |
208 | atomic_inc(&m->error_count); | |
209 | ||
210 | if (test_and_set_bit(error_type, &m->error_type)) | |
211 | return; | |
212 | ||
d460c65a JB |
213 | if (!errors_handled(ms)) |
214 | return; | |
215 | ||
72f4b314 JB |
216 | if (m != get_default_mirror(ms)) |
217 | goto out; | |
218 | ||
219 | if (!ms->in_sync) { | |
220 | /* | |
221 | * Better to issue requests to same failing device | |
222 | * than to risk returning corrupt data. | |
223 | */ | |
224 | DMERR("Primary mirror (%s) failed while out-of-sync: " | |
225 | "Reads may fail.", m->dev->name); | |
226 | goto out; | |
227 | } | |
228 | ||
229 | for (new = ms->mirror; new < ms->mirror + ms->nr_mirrors; new++) | |
230 | if (!atomic_read(&new->error_count)) { | |
231 | set_default_mirror(new); | |
232 | break; | |
233 | } | |
234 | ||
235 | if (unlikely(new == ms->mirror + ms->nr_mirrors)) | |
236 | DMWARN("All sides of mirror have failed."); | |
237 | ||
238 | out: | |
239 | schedule_work(&ms->trigger_event); | |
240 | } | |
241 | ||
c0da3748 MP |
242 | static int mirror_flush(struct dm_target *ti) |
243 | { | |
244 | struct mirror_set *ms = ti->private; | |
245 | unsigned long error_bits; | |
246 | ||
247 | unsigned int i; | |
248 | struct dm_io_region io[ms->nr_mirrors]; | |
249 | struct mirror *m; | |
250 | struct dm_io_request io_req = { | |
251 | .bi_rw = WRITE_BARRIER, | |
252 | .mem.type = DM_IO_KMEM, | |
253 | .mem.ptr.bvec = NULL, | |
254 | .client = ms->io_client, | |
255 | }; | |
256 | ||
257 | for (i = 0, m = ms->mirror; i < ms->nr_mirrors; i++, m++) { | |
258 | io[i].bdev = m->dev->bdev; | |
259 | io[i].sector = 0; | |
260 | io[i].count = 0; | |
261 | } | |
262 | ||
263 | error_bits = -1; | |
264 | dm_io(&io_req, ms->nr_mirrors, io, &error_bits); | |
265 | if (unlikely(error_bits != 0)) { | |
266 | for (i = 0; i < ms->nr_mirrors; i++) | |
267 | if (test_bit(i, &error_bits)) | |
268 | fail_mirror(ms->mirror + i, | |
64b30c46 | 269 | DM_RAID1_FLUSH_ERROR); |
c0da3748 MP |
270 | return -EIO; |
271 | } | |
272 | ||
273 | return 0; | |
274 | } | |
275 | ||
1da177e4 LT |
276 | /*----------------------------------------------------------------- |
277 | * Recovery. | |
278 | * | |
279 | * When a mirror is first activated we may find that some regions | |
280 | * are in the no-sync state. We have to recover these by | |
281 | * recopying from the default mirror to all the others. | |
282 | *---------------------------------------------------------------*/ | |
4cdc1d1f | 283 | static void recovery_complete(int read_err, unsigned long write_err, |
1da177e4 LT |
284 | void *context) |
285 | { | |
1f965b19 HM |
286 | struct dm_region *reg = context; |
287 | struct mirror_set *ms = dm_rh_region_context(reg); | |
8f0205b7 | 288 | int m, bit = 0; |
1da177e4 | 289 | |
8f0205b7 | 290 | if (read_err) { |
f44db678 JB |
291 | /* Read error means the failure of default mirror. */ |
292 | DMERR_LIMIT("Unable to read primary mirror during recovery"); | |
8f0205b7 JB |
293 | fail_mirror(get_default_mirror(ms), DM_RAID1_SYNC_ERROR); |
294 | } | |
f44db678 | 295 | |
8f0205b7 | 296 | if (write_err) { |
4cdc1d1f | 297 | DMERR_LIMIT("Write error during recovery (error = 0x%lx)", |
f44db678 | 298 | write_err); |
8f0205b7 JB |
299 | /* |
300 | * Bits correspond to devices (excluding default mirror). | |
301 | * The default mirror cannot change during recovery. | |
302 | */ | |
303 | for (m = 0; m < ms->nr_mirrors; m++) { | |
304 | if (&ms->mirror[m] == get_default_mirror(ms)) | |
305 | continue; | |
306 | if (test_bit(bit, &write_err)) | |
307 | fail_mirror(ms->mirror + m, | |
308 | DM_RAID1_SYNC_ERROR); | |
309 | bit++; | |
310 | } | |
311 | } | |
f44db678 | 312 | |
1f965b19 | 313 | dm_rh_recovery_end(reg, !(read_err || write_err)); |
1da177e4 LT |
314 | } |
315 | ||
1f965b19 | 316 | static int recover(struct mirror_set *ms, struct dm_region *reg) |
1da177e4 LT |
317 | { |
318 | int r; | |
1f965b19 | 319 | unsigned i; |
eb69aca5 | 320 | struct dm_io_region from, to[DM_KCOPYD_MAX_REGIONS], *dest; |
1da177e4 LT |
321 | struct mirror *m; |
322 | unsigned long flags = 0; | |
1f965b19 HM |
323 | region_t key = dm_rh_get_region_key(reg); |
324 | sector_t region_size = dm_rh_get_region_size(ms->rh); | |
1da177e4 LT |
325 | |
326 | /* fill in the source */ | |
72f4b314 | 327 | m = get_default_mirror(ms); |
1da177e4 | 328 | from.bdev = m->dev->bdev; |
1f965b19 HM |
329 | from.sector = m->offset + dm_rh_region_to_sector(ms->rh, key); |
330 | if (key == (ms->nr_regions - 1)) { | |
1da177e4 LT |
331 | /* |
332 | * The final region may be smaller than | |
333 | * region_size. | |
334 | */ | |
1f965b19 | 335 | from.count = ms->ti->len & (region_size - 1); |
1da177e4 | 336 | if (!from.count) |
1f965b19 | 337 | from.count = region_size; |
1da177e4 | 338 | } else |
1f965b19 | 339 | from.count = region_size; |
1da177e4 LT |
340 | |
341 | /* fill in the destinations */ | |
342 | for (i = 0, dest = to; i < ms->nr_mirrors; i++) { | |
72f4b314 | 343 | if (&ms->mirror[i] == get_default_mirror(ms)) |
1da177e4 LT |
344 | continue; |
345 | ||
346 | m = ms->mirror + i; | |
347 | dest->bdev = m->dev->bdev; | |
1f965b19 | 348 | dest->sector = m->offset + dm_rh_region_to_sector(ms->rh, key); |
1da177e4 LT |
349 | dest->count = from.count; |
350 | dest++; | |
351 | } | |
352 | ||
353 | /* hand to kcopyd */ | |
f7c83e2e JB |
354 | if (!errors_handled(ms)) |
355 | set_bit(DM_KCOPYD_IGNORE_ERROR, &flags); | |
356 | ||
eb69aca5 HM |
357 | r = dm_kcopyd_copy(ms->kcopyd_client, &from, ms->nr_mirrors - 1, to, |
358 | flags, recovery_complete, reg); | |
1da177e4 LT |
359 | |
360 | return r; | |
361 | } | |
362 | ||
363 | static void do_recovery(struct mirror_set *ms) | |
364 | { | |
1f965b19 HM |
365 | struct dm_region *reg; |
366 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); | |
1da177e4 | 367 | int r; |
1da177e4 LT |
368 | |
369 | /* | |
370 | * Start quiescing some regions. | |
371 | */ | |
1f965b19 | 372 | dm_rh_recovery_prepare(ms->rh); |
1da177e4 LT |
373 | |
374 | /* | |
375 | * Copy any already quiesced regions. | |
376 | */ | |
1f965b19 | 377 | while ((reg = dm_rh_recovery_start(ms->rh))) { |
1da177e4 LT |
378 | r = recover(ms, reg); |
379 | if (r) | |
1f965b19 | 380 | dm_rh_recovery_end(reg, 0); |
1da177e4 LT |
381 | } |
382 | ||
383 | /* | |
384 | * Update the in sync flag. | |
385 | */ | |
386 | if (!ms->in_sync && | |
387 | (log->type->get_sync_count(log) == ms->nr_regions)) { | |
388 | /* the sync is complete */ | |
389 | dm_table_event(ms->ti->table); | |
390 | ms->in_sync = 1; | |
391 | } | |
392 | } | |
393 | ||
394 | /*----------------------------------------------------------------- | |
395 | * Reads | |
396 | *---------------------------------------------------------------*/ | |
397 | static struct mirror *choose_mirror(struct mirror_set *ms, sector_t sector) | |
398 | { | |
06386bbf JB |
399 | struct mirror *m = get_default_mirror(ms); |
400 | ||
401 | do { | |
402 | if (likely(!atomic_read(&m->error_count))) | |
403 | return m; | |
404 | ||
405 | if (m-- == ms->mirror) | |
406 | m += ms->nr_mirrors; | |
407 | } while (m != get_default_mirror(ms)); | |
408 | ||
409 | return NULL; | |
410 | } | |
411 | ||
412 | static int default_ok(struct mirror *m) | |
413 | { | |
414 | struct mirror *default_mirror = get_default_mirror(m->ms); | |
415 | ||
416 | return !atomic_read(&default_mirror->error_count); | |
417 | } | |
418 | ||
419 | static int mirror_available(struct mirror_set *ms, struct bio *bio) | |
420 | { | |
1f965b19 HM |
421 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
422 | region_t region = dm_rh_bio_to_region(ms->rh, bio); | |
06386bbf | 423 | |
1f965b19 | 424 | if (log->type->in_sync(log, region, 0)) |
06386bbf JB |
425 | return choose_mirror(ms, bio->bi_sector) ? 1 : 0; |
426 | ||
427 | return 0; | |
1da177e4 LT |
428 | } |
429 | ||
430 | /* | |
431 | * remap a buffer to a particular mirror. | |
432 | */ | |
06386bbf JB |
433 | static sector_t map_sector(struct mirror *m, struct bio *bio) |
434 | { | |
4184153f MP |
435 | if (unlikely(!bio->bi_size)) |
436 | return 0; | |
06386bbf JB |
437 | return m->offset + (bio->bi_sector - m->ms->ti->begin); |
438 | } | |
439 | ||
440 | static void map_bio(struct mirror *m, struct bio *bio) | |
1da177e4 LT |
441 | { |
442 | bio->bi_bdev = m->dev->bdev; | |
06386bbf JB |
443 | bio->bi_sector = map_sector(m, bio); |
444 | } | |
445 | ||
22a1ceb1 | 446 | static void map_region(struct dm_io_region *io, struct mirror *m, |
06386bbf JB |
447 | struct bio *bio) |
448 | { | |
449 | io->bdev = m->dev->bdev; | |
450 | io->sector = map_sector(m, bio); | |
451 | io->count = bio->bi_size >> 9; | |
452 | } | |
453 | ||
04788507 MP |
454 | static void hold_bio(struct mirror_set *ms, struct bio *bio) |
455 | { | |
456 | /* | |
457 | * If device is suspended, complete the bio. | |
458 | */ | |
459 | if (atomic_read(&ms->suspend)) { | |
460 | if (dm_noflush_suspending(ms->ti)) | |
461 | bio_endio(bio, DM_ENDIO_REQUEUE); | |
462 | else | |
463 | bio_endio(bio, -EIO); | |
464 | return; | |
465 | } | |
466 | ||
467 | /* | |
468 | * Hold bio until the suspend is complete. | |
469 | */ | |
470 | spin_lock_irq(&ms->lock); | |
471 | bio_list_add(&ms->holds, bio); | |
472 | spin_unlock_irq(&ms->lock); | |
473 | } | |
474 | ||
06386bbf JB |
475 | /*----------------------------------------------------------------- |
476 | * Reads | |
477 | *---------------------------------------------------------------*/ | |
478 | static void read_callback(unsigned long error, void *context) | |
479 | { | |
480 | struct bio *bio = context; | |
481 | struct mirror *m; | |
482 | ||
483 | m = bio_get_m(bio); | |
484 | bio_set_m(bio, NULL); | |
485 | ||
486 | if (likely(!error)) { | |
487 | bio_endio(bio, 0); | |
488 | return; | |
489 | } | |
490 | ||
491 | fail_mirror(m, DM_RAID1_READ_ERROR); | |
492 | ||
493 | if (likely(default_ok(m)) || mirror_available(m->ms, bio)) { | |
494 | DMWARN_LIMIT("Read failure on mirror device %s. " | |
495 | "Trying alternative device.", | |
496 | m->dev->name); | |
497 | queue_bio(m->ms, bio, bio_rw(bio)); | |
498 | return; | |
499 | } | |
500 | ||
501 | DMERR_LIMIT("Read failure on mirror device %s. Failing I/O.", | |
502 | m->dev->name); | |
503 | bio_endio(bio, -EIO); | |
504 | } | |
505 | ||
506 | /* Asynchronous read. */ | |
507 | static void read_async_bio(struct mirror *m, struct bio *bio) | |
508 | { | |
22a1ceb1 | 509 | struct dm_io_region io; |
06386bbf JB |
510 | struct dm_io_request io_req = { |
511 | .bi_rw = READ, | |
512 | .mem.type = DM_IO_BVEC, | |
513 | .mem.ptr.bvec = bio->bi_io_vec + bio->bi_idx, | |
514 | .notify.fn = read_callback, | |
515 | .notify.context = bio, | |
516 | .client = m->ms->io_client, | |
517 | }; | |
518 | ||
519 | map_region(&io, m, bio); | |
520 | bio_set_m(bio, m); | |
1f965b19 HM |
521 | BUG_ON(dm_io(&io_req, 1, &io, NULL)); |
522 | } | |
523 | ||
524 | static inline int region_in_sync(struct mirror_set *ms, region_t region, | |
525 | int may_block) | |
526 | { | |
527 | int state = dm_rh_get_state(ms->rh, region, may_block); | |
528 | return state == DM_RH_CLEAN || state == DM_RH_DIRTY; | |
1da177e4 LT |
529 | } |
530 | ||
531 | static void do_reads(struct mirror_set *ms, struct bio_list *reads) | |
532 | { | |
533 | region_t region; | |
534 | struct bio *bio; | |
535 | struct mirror *m; | |
536 | ||
537 | while ((bio = bio_list_pop(reads))) { | |
1f965b19 | 538 | region = dm_rh_bio_to_region(ms->rh, bio); |
06386bbf | 539 | m = get_default_mirror(ms); |
1da177e4 LT |
540 | |
541 | /* | |
542 | * We can only read balance if the region is in sync. | |
543 | */ | |
1f965b19 | 544 | if (likely(region_in_sync(ms, region, 1))) |
1da177e4 | 545 | m = choose_mirror(ms, bio->bi_sector); |
06386bbf JB |
546 | else if (m && atomic_read(&m->error_count)) |
547 | m = NULL; | |
1da177e4 | 548 | |
06386bbf JB |
549 | if (likely(m)) |
550 | read_async_bio(m, bio); | |
551 | else | |
552 | bio_endio(bio, -EIO); | |
1da177e4 LT |
553 | } |
554 | } | |
555 | ||
556 | /*----------------------------------------------------------------- | |
557 | * Writes. | |
558 | * | |
559 | * We do different things with the write io depending on the | |
560 | * state of the region that it's in: | |
561 | * | |
562 | * SYNC: increment pending, use kcopyd to write to *all* mirrors | |
563 | * RECOVERING: delay the io until recovery completes | |
564 | * NOSYNC: increment pending, just write to the default mirror | |
565 | *---------------------------------------------------------------*/ | |
72f4b314 | 566 | |
72f4b314 | 567 | |
1da177e4 LT |
568 | static void write_callback(unsigned long error, void *context) |
569 | { | |
72f4b314 | 570 | unsigned i, ret = 0; |
1da177e4 LT |
571 | struct bio *bio = (struct bio *) context; |
572 | struct mirror_set *ms; | |
72f4b314 JB |
573 | int uptodate = 0; |
574 | int should_wake = 0; | |
575 | unsigned long flags; | |
1da177e4 | 576 | |
06386bbf JB |
577 | ms = bio_get_m(bio)->ms; |
578 | bio_set_m(bio, NULL); | |
1da177e4 LT |
579 | |
580 | /* | |
581 | * NOTE: We don't decrement the pending count here, | |
582 | * instead it is done by the targets endio function. | |
583 | * This way we handle both writes to SYNC and NOSYNC | |
584 | * regions with the same code. | |
585 | */ | |
72f4b314 JB |
586 | if (likely(!error)) |
587 | goto out; | |
1da177e4 | 588 | |
72f4b314 JB |
589 | for (i = 0; i < ms->nr_mirrors; i++) |
590 | if (test_bit(i, &error)) | |
591 | fail_mirror(ms->mirror + i, DM_RAID1_WRITE_ERROR); | |
592 | else | |
593 | uptodate = 1; | |
594 | ||
595 | if (unlikely(!uptodate)) { | |
596 | DMERR("All replicated volumes dead, failing I/O"); | |
597 | /* None of the writes succeeded, fail the I/O. */ | |
598 | ret = -EIO; | |
599 | } else if (errors_handled(ms)) { | |
1da177e4 | 600 | /* |
72f4b314 JB |
601 | * Need to raise event. Since raising |
602 | * events can block, we need to do it in | |
603 | * the main thread. | |
1da177e4 | 604 | */ |
72f4b314 JB |
605 | spin_lock_irqsave(&ms->lock, flags); |
606 | if (!ms->failures.head) | |
607 | should_wake = 1; | |
608 | bio_list_add(&ms->failures, bio); | |
609 | spin_unlock_irqrestore(&ms->lock, flags); | |
610 | if (should_wake) | |
1f965b19 | 611 | wakeup_mirrord(ms); |
72f4b314 | 612 | return; |
1da177e4 | 613 | } |
72f4b314 JB |
614 | out: |
615 | bio_endio(bio, ret); | |
1da177e4 LT |
616 | } |
617 | ||
618 | static void do_write(struct mirror_set *ms, struct bio *bio) | |
619 | { | |
620 | unsigned int i; | |
22a1ceb1 | 621 | struct dm_io_region io[ms->nr_mirrors], *dest = io; |
1da177e4 | 622 | struct mirror *m; |
88be163a | 623 | struct dm_io_request io_req = { |
4184153f | 624 | .bi_rw = WRITE | (bio->bi_rw & WRITE_BARRIER), |
88be163a MB |
625 | .mem.type = DM_IO_BVEC, |
626 | .mem.ptr.bvec = bio->bi_io_vec + bio->bi_idx, | |
627 | .notify.fn = write_callback, | |
628 | .notify.context = bio, | |
629 | .client = ms->io_client, | |
630 | }; | |
1da177e4 | 631 | |
06386bbf JB |
632 | for (i = 0, m = ms->mirror; i < ms->nr_mirrors; i++, m++) |
633 | map_region(dest++, m, bio); | |
1da177e4 | 634 | |
06386bbf JB |
635 | /* |
636 | * Use default mirror because we only need it to retrieve the reference | |
637 | * to the mirror set in write_callback(). | |
638 | */ | |
639 | bio_set_m(bio, get_default_mirror(ms)); | |
88be163a | 640 | |
1f965b19 | 641 | BUG_ON(dm_io(&io_req, ms->nr_mirrors, io, NULL)); |
1da177e4 LT |
642 | } |
643 | ||
644 | static void do_writes(struct mirror_set *ms, struct bio_list *writes) | |
645 | { | |
646 | int state; | |
647 | struct bio *bio; | |
648 | struct bio_list sync, nosync, recover, *this_list = NULL; | |
7513c2a7 JB |
649 | struct bio_list requeue; |
650 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); | |
651 | region_t region; | |
1da177e4 LT |
652 | |
653 | if (!writes->head) | |
654 | return; | |
655 | ||
656 | /* | |
657 | * Classify each write. | |
658 | */ | |
659 | bio_list_init(&sync); | |
660 | bio_list_init(&nosync); | |
661 | bio_list_init(&recover); | |
7513c2a7 | 662 | bio_list_init(&requeue); |
1da177e4 LT |
663 | |
664 | while ((bio = bio_list_pop(writes))) { | |
4184153f MP |
665 | if (unlikely(bio_empty_barrier(bio))) { |
666 | bio_list_add(&sync, bio); | |
667 | continue; | |
668 | } | |
669 | ||
7513c2a7 JB |
670 | region = dm_rh_bio_to_region(ms->rh, bio); |
671 | ||
672 | if (log->type->is_remote_recovering && | |
673 | log->type->is_remote_recovering(log, region)) { | |
674 | bio_list_add(&requeue, bio); | |
675 | continue; | |
676 | } | |
677 | ||
678 | state = dm_rh_get_state(ms->rh, region, 1); | |
1da177e4 | 679 | switch (state) { |
1f965b19 HM |
680 | case DM_RH_CLEAN: |
681 | case DM_RH_DIRTY: | |
1da177e4 LT |
682 | this_list = &sync; |
683 | break; | |
684 | ||
1f965b19 | 685 | case DM_RH_NOSYNC: |
1da177e4 LT |
686 | this_list = &nosync; |
687 | break; | |
688 | ||
1f965b19 | 689 | case DM_RH_RECOVERING: |
1da177e4 LT |
690 | this_list = &recover; |
691 | break; | |
692 | } | |
693 | ||
694 | bio_list_add(this_list, bio); | |
695 | } | |
696 | ||
7513c2a7 JB |
697 | /* |
698 | * Add bios that are delayed due to remote recovery | |
699 | * back on to the write queue | |
700 | */ | |
701 | if (unlikely(requeue.head)) { | |
702 | spin_lock_irq(&ms->lock); | |
703 | bio_list_merge(&ms->writes, &requeue); | |
704 | spin_unlock_irq(&ms->lock); | |
69885683 | 705 | delayed_wake(ms); |
7513c2a7 JB |
706 | } |
707 | ||
1da177e4 LT |
708 | /* |
709 | * Increment the pending counts for any regions that will | |
710 | * be written to (writes to recover regions are going to | |
711 | * be delayed). | |
712 | */ | |
1f965b19 HM |
713 | dm_rh_inc_pending(ms->rh, &sync); |
714 | dm_rh_inc_pending(ms->rh, &nosync); | |
d2b69864 JB |
715 | |
716 | /* | |
717 | * If the flush fails on a previous call and succeeds here, | |
718 | * we must not reset the log_failure variable. We need | |
719 | * userspace interaction to do that. | |
720 | */ | |
721 | ms->log_failure = dm_rh_flush(ms->rh) ? 1 : ms->log_failure; | |
1da177e4 LT |
722 | |
723 | /* | |
724 | * Dispatch io. | |
725 | */ | |
b80aa7a0 JB |
726 | if (unlikely(ms->log_failure)) { |
727 | spin_lock_irq(&ms->lock); | |
728 | bio_list_merge(&ms->failures, &sync); | |
729 | spin_unlock_irq(&ms->lock); | |
1f965b19 | 730 | wakeup_mirrord(ms); |
b80aa7a0 | 731 | } else |
fc1ff958 | 732 | while ((bio = bio_list_pop(&sync))) |
b80aa7a0 | 733 | do_write(ms, bio); |
1da177e4 LT |
734 | |
735 | while ((bio = bio_list_pop(&recover))) | |
1f965b19 | 736 | dm_rh_delay(ms->rh, bio); |
1da177e4 LT |
737 | |
738 | while ((bio = bio_list_pop(&nosync))) { | |
06386bbf | 739 | map_bio(get_default_mirror(ms), bio); |
1da177e4 LT |
740 | generic_make_request(bio); |
741 | } | |
742 | } | |
743 | ||
72f4b314 JB |
744 | static void do_failures(struct mirror_set *ms, struct bio_list *failures) |
745 | { | |
746 | struct bio *bio; | |
747 | ||
0f398a84 | 748 | if (likely(!failures->head)) |
72f4b314 JB |
749 | return; |
750 | ||
b80aa7a0 JB |
751 | /* |
752 | * If the log has failed, unattempted writes are being | |
0f398a84 | 753 | * put on the holds list. We can't issue those writes |
b80aa7a0 JB |
754 | * until a log has been marked, so we must store them. |
755 | * | |
756 | * If a 'noflush' suspend is in progress, we can requeue | |
757 | * the I/O's to the core. This give userspace a chance | |
758 | * to reconfigure the mirror, at which point the core | |
759 | * will reissue the writes. If the 'noflush' flag is | |
760 | * not set, we have no choice but to return errors. | |
761 | * | |
762 | * Some writes on the failures list may have been | |
763 | * submitted before the log failure and represent a | |
764 | * failure to write to one of the devices. It is ok | |
765 | * for us to treat them the same and requeue them | |
766 | * as well. | |
767 | */ | |
b80aa7a0 | 768 | |
0f398a84 MP |
769 | while ((bio = bio_list_pop(failures))) { |
770 | if (ms->log_failure) | |
771 | hold_bio(ms, bio); | |
772 | else { | |
773 | ms->in_sync = 0; | |
774 | dm_rh_mark_nosync(ms->rh, bio, bio->bi_size, 0); | |
775 | } | |
b80aa7a0 | 776 | } |
72f4b314 JB |
777 | } |
778 | ||
779 | static void trigger_event(struct work_struct *work) | |
780 | { | |
781 | struct mirror_set *ms = | |
782 | container_of(work, struct mirror_set, trigger_event); | |
783 | ||
784 | dm_table_event(ms->ti->table); | |
785 | } | |
786 | ||
1da177e4 LT |
787 | /*----------------------------------------------------------------- |
788 | * kmirrord | |
789 | *---------------------------------------------------------------*/ | |
a2aebe03 | 790 | static void do_mirror(struct work_struct *work) |
1da177e4 | 791 | { |
1f965b19 HM |
792 | struct mirror_set *ms = container_of(work, struct mirror_set, |
793 | kmirrord_work); | |
72f4b314 JB |
794 | struct bio_list reads, writes, failures; |
795 | unsigned long flags; | |
1da177e4 | 796 | |
72f4b314 | 797 | spin_lock_irqsave(&ms->lock, flags); |
1da177e4 LT |
798 | reads = ms->reads; |
799 | writes = ms->writes; | |
72f4b314 | 800 | failures = ms->failures; |
1da177e4 LT |
801 | bio_list_init(&ms->reads); |
802 | bio_list_init(&ms->writes); | |
72f4b314 JB |
803 | bio_list_init(&ms->failures); |
804 | spin_unlock_irqrestore(&ms->lock, flags); | |
1da177e4 | 805 | |
1f965b19 | 806 | dm_rh_update_states(ms->rh, errors_handled(ms)); |
1da177e4 LT |
807 | do_recovery(ms); |
808 | do_reads(ms, &reads); | |
809 | do_writes(ms, &writes); | |
72f4b314 | 810 | do_failures(ms, &failures); |
7ff14a36 MP |
811 | |
812 | dm_table_unplug_all(ms->ti->table); | |
1da177e4 LT |
813 | } |
814 | ||
1da177e4 LT |
815 | /*----------------------------------------------------------------- |
816 | * Target functions | |
817 | *---------------------------------------------------------------*/ | |
818 | static struct mirror_set *alloc_context(unsigned int nr_mirrors, | |
819 | uint32_t region_size, | |
820 | struct dm_target *ti, | |
416cd17b | 821 | struct dm_dirty_log *dl) |
1da177e4 LT |
822 | { |
823 | size_t len; | |
824 | struct mirror_set *ms = NULL; | |
825 | ||
1da177e4 LT |
826 | len = sizeof(*ms) + (sizeof(ms->mirror[0]) * nr_mirrors); |
827 | ||
dd00cc48 | 828 | ms = kzalloc(len, GFP_KERNEL); |
1da177e4 | 829 | if (!ms) { |
72d94861 | 830 | ti->error = "Cannot allocate mirror context"; |
1da177e4 LT |
831 | return NULL; |
832 | } | |
833 | ||
1da177e4 LT |
834 | spin_lock_init(&ms->lock); |
835 | ||
836 | ms->ti = ti; | |
837 | ms->nr_mirrors = nr_mirrors; | |
838 | ms->nr_regions = dm_sector_div_up(ti->len, region_size); | |
839 | ms->in_sync = 0; | |
b80aa7a0 JB |
840 | ms->log_failure = 0; |
841 | atomic_set(&ms->suspend, 0); | |
72f4b314 | 842 | atomic_set(&ms->default_mirror, DEFAULT_MIRROR); |
1da177e4 | 843 | |
95f8fac8 MP |
844 | ms->read_record_pool = mempool_create_slab_pool(MIN_READ_RECORDS, |
845 | _dm_raid1_read_record_cache); | |
846 | ||
06386bbf JB |
847 | if (!ms->read_record_pool) { |
848 | ti->error = "Error creating mirror read_record_pool"; | |
849 | kfree(ms); | |
850 | return NULL; | |
851 | } | |
852 | ||
88be163a MB |
853 | ms->io_client = dm_io_client_create(DM_IO_PAGES); |
854 | if (IS_ERR(ms->io_client)) { | |
855 | ti->error = "Error creating dm_io client"; | |
06386bbf | 856 | mempool_destroy(ms->read_record_pool); |
88be163a MB |
857 | kfree(ms); |
858 | return NULL; | |
859 | } | |
860 | ||
1f965b19 HM |
861 | ms->rh = dm_region_hash_create(ms, dispatch_bios, wakeup_mirrord, |
862 | wakeup_all_recovery_waiters, | |
863 | ms->ti->begin, MAX_RECOVERY, | |
864 | dl, region_size, ms->nr_regions); | |
865 | if (IS_ERR(ms->rh)) { | |
72d94861 | 866 | ti->error = "Error creating dirty region hash"; |
a72cf737 | 867 | dm_io_client_destroy(ms->io_client); |
06386bbf | 868 | mempool_destroy(ms->read_record_pool); |
1da177e4 LT |
869 | kfree(ms); |
870 | return NULL; | |
871 | } | |
872 | ||
873 | return ms; | |
874 | } | |
875 | ||
876 | static void free_context(struct mirror_set *ms, struct dm_target *ti, | |
877 | unsigned int m) | |
878 | { | |
879 | while (m--) | |
880 | dm_put_device(ti, ms->mirror[m].dev); | |
881 | ||
88be163a | 882 | dm_io_client_destroy(ms->io_client); |
1f965b19 | 883 | dm_region_hash_destroy(ms->rh); |
06386bbf | 884 | mempool_destroy(ms->read_record_pool); |
1da177e4 LT |
885 | kfree(ms); |
886 | } | |
887 | ||
1da177e4 LT |
888 | static int get_mirror(struct mirror_set *ms, struct dm_target *ti, |
889 | unsigned int mirror, char **argv) | |
890 | { | |
4ee218cd | 891 | unsigned long long offset; |
1da177e4 | 892 | |
4ee218cd | 893 | if (sscanf(argv[1], "%llu", &offset) != 1) { |
72d94861 | 894 | ti->error = "Invalid offset"; |
1da177e4 LT |
895 | return -EINVAL; |
896 | } | |
897 | ||
898 | if (dm_get_device(ti, argv[0], offset, ti->len, | |
899 | dm_table_get_mode(ti->table), | |
900 | &ms->mirror[mirror].dev)) { | |
72d94861 | 901 | ti->error = "Device lookup failure"; |
1da177e4 LT |
902 | return -ENXIO; |
903 | } | |
904 | ||
aa5617c5 | 905 | ms->mirror[mirror].ms = ms; |
72f4b314 JB |
906 | atomic_set(&(ms->mirror[mirror].error_count), 0); |
907 | ms->mirror[mirror].error_type = 0; | |
1da177e4 LT |
908 | ms->mirror[mirror].offset = offset; |
909 | ||
910 | return 0; | |
911 | } | |
912 | ||
1da177e4 LT |
913 | /* |
914 | * Create dirty log: log_type #log_params <log_params> | |
915 | */ | |
416cd17b | 916 | static struct dm_dirty_log *create_dirty_log(struct dm_target *ti, |
1f965b19 HM |
917 | unsigned argc, char **argv, |
918 | unsigned *args_used) | |
1da177e4 | 919 | { |
1f965b19 | 920 | unsigned param_count; |
416cd17b | 921 | struct dm_dirty_log *dl; |
1da177e4 LT |
922 | |
923 | if (argc < 2) { | |
72d94861 | 924 | ti->error = "Insufficient mirror log arguments"; |
1da177e4 LT |
925 | return NULL; |
926 | } | |
927 | ||
928 | if (sscanf(argv[1], "%u", ¶m_count) != 1) { | |
72d94861 | 929 | ti->error = "Invalid mirror log argument count"; |
1da177e4 LT |
930 | return NULL; |
931 | } | |
932 | ||
933 | *args_used = 2 + param_count; | |
934 | ||
935 | if (argc < *args_used) { | |
72d94861 | 936 | ti->error = "Insufficient mirror log arguments"; |
1da177e4 LT |
937 | return NULL; |
938 | } | |
939 | ||
c0da3748 MP |
940 | dl = dm_dirty_log_create(argv[0], ti, mirror_flush, param_count, |
941 | argv + 2); | |
1da177e4 | 942 | if (!dl) { |
72d94861 | 943 | ti->error = "Error creating mirror dirty log"; |
1da177e4 LT |
944 | return NULL; |
945 | } | |
946 | ||
1da177e4 LT |
947 | return dl; |
948 | } | |
949 | ||
a8e6afa2 JB |
950 | static int parse_features(struct mirror_set *ms, unsigned argc, char **argv, |
951 | unsigned *args_used) | |
952 | { | |
953 | unsigned num_features; | |
954 | struct dm_target *ti = ms->ti; | |
955 | ||
956 | *args_used = 0; | |
957 | ||
958 | if (!argc) | |
959 | return 0; | |
960 | ||
961 | if (sscanf(argv[0], "%u", &num_features) != 1) { | |
962 | ti->error = "Invalid number of features"; | |
963 | return -EINVAL; | |
964 | } | |
965 | ||
966 | argc--; | |
967 | argv++; | |
968 | (*args_used)++; | |
969 | ||
970 | if (num_features > argc) { | |
971 | ti->error = "Not enough arguments to support feature count"; | |
972 | return -EINVAL; | |
973 | } | |
974 | ||
975 | if (!strcmp("handle_errors", argv[0])) | |
976 | ms->features |= DM_RAID1_HANDLE_ERRORS; | |
977 | else { | |
978 | ti->error = "Unrecognised feature requested"; | |
979 | return -EINVAL; | |
980 | } | |
981 | ||
982 | (*args_used)++; | |
983 | ||
984 | return 0; | |
985 | } | |
986 | ||
1da177e4 LT |
987 | /* |
988 | * Construct a mirror mapping: | |
989 | * | |
990 | * log_type #log_params <log_params> | |
991 | * #mirrors [mirror_path offset]{2,} | |
a8e6afa2 | 992 | * [#features <features>] |
1da177e4 LT |
993 | * |
994 | * log_type is "core" or "disk" | |
995 | * #log_params is between 1 and 3 | |
a8e6afa2 JB |
996 | * |
997 | * If present, features must be "handle_errors". | |
1da177e4 | 998 | */ |
1da177e4 LT |
999 | static int mirror_ctr(struct dm_target *ti, unsigned int argc, char **argv) |
1000 | { | |
1001 | int r; | |
1002 | unsigned int nr_mirrors, m, args_used; | |
1003 | struct mirror_set *ms; | |
416cd17b | 1004 | struct dm_dirty_log *dl; |
1da177e4 LT |
1005 | |
1006 | dl = create_dirty_log(ti, argc, argv, &args_used); | |
1007 | if (!dl) | |
1008 | return -EINVAL; | |
1009 | ||
1010 | argv += args_used; | |
1011 | argc -= args_used; | |
1012 | ||
1013 | if (!argc || sscanf(argv[0], "%u", &nr_mirrors) != 1 || | |
eb69aca5 | 1014 | nr_mirrors < 2 || nr_mirrors > DM_KCOPYD_MAX_REGIONS + 1) { |
72d94861 | 1015 | ti->error = "Invalid number of mirrors"; |
416cd17b | 1016 | dm_dirty_log_destroy(dl); |
1da177e4 LT |
1017 | return -EINVAL; |
1018 | } | |
1019 | ||
1020 | argv++, argc--; | |
1021 | ||
a8e6afa2 JB |
1022 | if (argc < nr_mirrors * 2) { |
1023 | ti->error = "Too few mirror arguments"; | |
416cd17b | 1024 | dm_dirty_log_destroy(dl); |
1da177e4 LT |
1025 | return -EINVAL; |
1026 | } | |
1027 | ||
1028 | ms = alloc_context(nr_mirrors, dl->type->get_region_size(dl), ti, dl); | |
1029 | if (!ms) { | |
416cd17b | 1030 | dm_dirty_log_destroy(dl); |
1da177e4 LT |
1031 | return -ENOMEM; |
1032 | } | |
1033 | ||
1034 | /* Get the mirror parameter sets */ | |
1035 | for (m = 0; m < nr_mirrors; m++) { | |
1036 | r = get_mirror(ms, ti, m, argv); | |
1037 | if (r) { | |
1038 | free_context(ms, ti, m); | |
1039 | return r; | |
1040 | } | |
1041 | argv += 2; | |
1042 | argc -= 2; | |
1043 | } | |
1044 | ||
1045 | ti->private = ms; | |
1f965b19 | 1046 | ti->split_io = dm_rh_get_region_size(ms->rh); |
4184153f | 1047 | ti->num_flush_requests = 1; |
1da177e4 | 1048 | |
6ad36fe2 HS |
1049 | ms->kmirrord_wq = create_singlethread_workqueue("kmirrord"); |
1050 | if (!ms->kmirrord_wq) { | |
1051 | DMERR("couldn't start kmirrord"); | |
a72cf737 DM |
1052 | r = -ENOMEM; |
1053 | goto err_free_context; | |
6ad36fe2 HS |
1054 | } |
1055 | INIT_WORK(&ms->kmirrord_work, do_mirror); | |
a2aebe03 MP |
1056 | init_timer(&ms->timer); |
1057 | ms->timer_pending = 0; | |
72f4b314 | 1058 | INIT_WORK(&ms->trigger_event, trigger_event); |
6ad36fe2 | 1059 | |
a8e6afa2 | 1060 | r = parse_features(ms, argc, argv, &args_used); |
a72cf737 DM |
1061 | if (r) |
1062 | goto err_destroy_wq; | |
a8e6afa2 JB |
1063 | |
1064 | argv += args_used; | |
1065 | argc -= args_used; | |
1066 | ||
f44db678 JB |
1067 | /* |
1068 | * Any read-balancing addition depends on the | |
1069 | * DM_RAID1_HANDLE_ERRORS flag being present. | |
1070 | * This is because the decision to balance depends | |
1071 | * on the sync state of a region. If the above | |
1072 | * flag is not present, we ignore errors; and | |
1073 | * the sync state may be inaccurate. | |
1074 | */ | |
1075 | ||
a8e6afa2 JB |
1076 | if (argc) { |
1077 | ti->error = "Too many mirror arguments"; | |
a72cf737 DM |
1078 | r = -EINVAL; |
1079 | goto err_destroy_wq; | |
a8e6afa2 JB |
1080 | } |
1081 | ||
1f965b19 | 1082 | r = dm_kcopyd_client_create(DM_KCOPYD_PAGES, &ms->kcopyd_client); |
a72cf737 DM |
1083 | if (r) |
1084 | goto err_destroy_wq; | |
1da177e4 | 1085 | |
1f965b19 | 1086 | wakeup_mirrord(ms); |
1da177e4 | 1087 | return 0; |
a72cf737 DM |
1088 | |
1089 | err_destroy_wq: | |
1090 | destroy_workqueue(ms->kmirrord_wq); | |
1091 | err_free_context: | |
1092 | free_context(ms, ti, ms->nr_mirrors); | |
1093 | return r; | |
1da177e4 LT |
1094 | } |
1095 | ||
1096 | static void mirror_dtr(struct dm_target *ti) | |
1097 | { | |
1098 | struct mirror_set *ms = (struct mirror_set *) ti->private; | |
1099 | ||
a2aebe03 | 1100 | del_timer_sync(&ms->timer); |
6ad36fe2 | 1101 | flush_workqueue(ms->kmirrord_wq); |
18776c73 | 1102 | flush_scheduled_work(); |
eb69aca5 | 1103 | dm_kcopyd_client_destroy(ms->kcopyd_client); |
6ad36fe2 | 1104 | destroy_workqueue(ms->kmirrord_wq); |
1da177e4 LT |
1105 | free_context(ms, ti, ms->nr_mirrors); |
1106 | } | |
1107 | ||
1da177e4 LT |
1108 | /* |
1109 | * Mirror mapping function | |
1110 | */ | |
1111 | static int mirror_map(struct dm_target *ti, struct bio *bio, | |
1112 | union map_info *map_context) | |
1113 | { | |
1114 | int r, rw = bio_rw(bio); | |
1115 | struct mirror *m; | |
1116 | struct mirror_set *ms = ti->private; | |
06386bbf | 1117 | struct dm_raid1_read_record *read_record = NULL; |
1f965b19 | 1118 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
1da177e4 LT |
1119 | |
1120 | if (rw == WRITE) { | |
06386bbf | 1121 | /* Save region for mirror_end_io() handler */ |
1f965b19 | 1122 | map_context->ll = dm_rh_bio_to_region(ms->rh, bio); |
1da177e4 | 1123 | queue_bio(ms, bio, rw); |
d2a7ad29 | 1124 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
1125 | } |
1126 | ||
1f965b19 | 1127 | r = log->type->in_sync(log, dm_rh_bio_to_region(ms->rh, bio), 0); |
1da177e4 LT |
1128 | if (r < 0 && r != -EWOULDBLOCK) |
1129 | return r; | |
1130 | ||
1da177e4 | 1131 | /* |
06386bbf | 1132 | * If region is not in-sync queue the bio. |
1da177e4 | 1133 | */ |
06386bbf JB |
1134 | if (!r || (r == -EWOULDBLOCK)) { |
1135 | if (rw == READA) | |
1136 | return -EWOULDBLOCK; | |
1da177e4 | 1137 | |
1da177e4 | 1138 | queue_bio(ms, bio, rw); |
d2a7ad29 | 1139 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
1140 | } |
1141 | ||
06386bbf JB |
1142 | /* |
1143 | * The region is in-sync and we can perform reads directly. | |
1144 | * Store enough information so we can retry if it fails. | |
1145 | */ | |
1da177e4 | 1146 | m = choose_mirror(ms, bio->bi_sector); |
06386bbf | 1147 | if (unlikely(!m)) |
1da177e4 LT |
1148 | return -EIO; |
1149 | ||
06386bbf JB |
1150 | read_record = mempool_alloc(ms->read_record_pool, GFP_NOIO); |
1151 | if (likely(read_record)) { | |
1152 | dm_bio_record(&read_record->details, bio); | |
1153 | map_context->ptr = read_record; | |
1154 | read_record->m = m; | |
1155 | } | |
1156 | ||
1157 | map_bio(m, bio); | |
1158 | ||
d2a7ad29 | 1159 | return DM_MAPIO_REMAPPED; |
1da177e4 LT |
1160 | } |
1161 | ||
1162 | static int mirror_end_io(struct dm_target *ti, struct bio *bio, | |
1163 | int error, union map_info *map_context) | |
1164 | { | |
1165 | int rw = bio_rw(bio); | |
1166 | struct mirror_set *ms = (struct mirror_set *) ti->private; | |
06386bbf JB |
1167 | struct mirror *m = NULL; |
1168 | struct dm_bio_details *bd = NULL; | |
1169 | struct dm_raid1_read_record *read_record = map_context->ptr; | |
1da177e4 LT |
1170 | |
1171 | /* | |
1172 | * We need to dec pending if this was a write. | |
1173 | */ | |
06386bbf | 1174 | if (rw == WRITE) { |
4184153f MP |
1175 | if (likely(!bio_empty_barrier(bio))) |
1176 | dm_rh_dec(ms->rh, map_context->ll); | |
06386bbf JB |
1177 | return error; |
1178 | } | |
1da177e4 | 1179 | |
06386bbf JB |
1180 | if (error == -EOPNOTSUPP) |
1181 | goto out; | |
1182 | ||
1f98a13f | 1183 | if ((error == -EWOULDBLOCK) && bio_rw_flagged(bio, BIO_RW_AHEAD)) |
06386bbf JB |
1184 | goto out; |
1185 | ||
1186 | if (unlikely(error)) { | |
1187 | if (!read_record) { | |
1188 | /* | |
1189 | * There wasn't enough memory to record necessary | |
1190 | * information for a retry or there was no other | |
1191 | * mirror in-sync. | |
1192 | */ | |
e03f1a84 | 1193 | DMERR_LIMIT("Mirror read failed."); |
06386bbf JB |
1194 | return -EIO; |
1195 | } | |
e03f1a84 AB |
1196 | |
1197 | m = read_record->m; | |
1198 | ||
06386bbf JB |
1199 | DMERR("Mirror read failed from %s. Trying alternative device.", |
1200 | m->dev->name); | |
1201 | ||
06386bbf JB |
1202 | fail_mirror(m, DM_RAID1_READ_ERROR); |
1203 | ||
1204 | /* | |
1205 | * A failed read is requeued for another attempt using an intact | |
1206 | * mirror. | |
1207 | */ | |
1208 | if (default_ok(m) || mirror_available(ms, bio)) { | |
1209 | bd = &read_record->details; | |
1210 | ||
1211 | dm_bio_restore(bd, bio); | |
1212 | mempool_free(read_record, ms->read_record_pool); | |
1213 | map_context->ptr = NULL; | |
1214 | queue_bio(ms, bio, rw); | |
1215 | return 1; | |
1216 | } | |
1217 | DMERR("All replicated volumes dead, failing I/O"); | |
1218 | } | |
1219 | ||
1220 | out: | |
1221 | if (read_record) { | |
1222 | mempool_free(read_record, ms->read_record_pool); | |
1223 | map_context->ptr = NULL; | |
1224 | } | |
1225 | ||
1226 | return error; | |
1da177e4 LT |
1227 | } |
1228 | ||
b80aa7a0 | 1229 | static void mirror_presuspend(struct dm_target *ti) |
1da177e4 LT |
1230 | { |
1231 | struct mirror_set *ms = (struct mirror_set *) ti->private; | |
1f965b19 | 1232 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
1da177e4 | 1233 | |
04788507 MP |
1234 | struct bio_list holds; |
1235 | struct bio *bio; | |
1236 | ||
b80aa7a0 JB |
1237 | atomic_set(&ms->suspend, 1); |
1238 | ||
1239 | /* | |
1240 | * We must finish up all the work that we've | |
1241 | * generated (i.e. recovery work). | |
1242 | */ | |
1f965b19 | 1243 | dm_rh_stop_recovery(ms->rh); |
33184048 | 1244 | |
33184048 | 1245 | wait_event(_kmirrord_recovery_stopped, |
1f965b19 | 1246 | !dm_rh_recovery_in_flight(ms->rh)); |
33184048 | 1247 | |
b80aa7a0 JB |
1248 | if (log->type->presuspend && log->type->presuspend(log)) |
1249 | /* FIXME: need better error handling */ | |
1250 | DMWARN("log presuspend failed"); | |
1251 | ||
1252 | /* | |
1253 | * Now that recovery is complete/stopped and the | |
1254 | * delayed bios are queued, we need to wait for | |
1255 | * the worker thread to complete. This way, | |
1256 | * we know that all of our I/O has been pushed. | |
1257 | */ | |
1258 | flush_workqueue(ms->kmirrord_wq); | |
04788507 MP |
1259 | |
1260 | /* | |
1261 | * Now set ms->suspend is set and the workqueue flushed, no more | |
1262 | * entries can be added to ms->hold list, so process it. | |
1263 | * | |
1264 | * Bios can still arrive concurrently with or after this | |
1265 | * presuspend function, but they cannot join the hold list | |
1266 | * because ms->suspend is set. | |
1267 | */ | |
1268 | spin_lock_irq(&ms->lock); | |
1269 | holds = ms->holds; | |
1270 | bio_list_init(&ms->holds); | |
1271 | spin_unlock_irq(&ms->lock); | |
1272 | ||
1273 | while ((bio = bio_list_pop(&holds))) | |
1274 | hold_bio(ms, bio); | |
b80aa7a0 JB |
1275 | } |
1276 | ||
1277 | static void mirror_postsuspend(struct dm_target *ti) | |
1278 | { | |
1279 | struct mirror_set *ms = ti->private; | |
1f965b19 | 1280 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
b80aa7a0 | 1281 | |
6b3df0d7 | 1282 | if (log->type->postsuspend && log->type->postsuspend(log)) |
1da177e4 | 1283 | /* FIXME: need better error handling */ |
b80aa7a0 | 1284 | DMWARN("log postsuspend failed"); |
1da177e4 LT |
1285 | } |
1286 | ||
1287 | static void mirror_resume(struct dm_target *ti) | |
1288 | { | |
b80aa7a0 | 1289 | struct mirror_set *ms = ti->private; |
1f965b19 | 1290 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
b80aa7a0 JB |
1291 | |
1292 | atomic_set(&ms->suspend, 0); | |
1da177e4 LT |
1293 | if (log->type->resume && log->type->resume(log)) |
1294 | /* FIXME: need better error handling */ | |
1295 | DMWARN("log resume failed"); | |
1f965b19 | 1296 | dm_rh_start_recovery(ms->rh); |
1da177e4 LT |
1297 | } |
1298 | ||
af195ac8 JB |
1299 | /* |
1300 | * device_status_char | |
1301 | * @m: mirror device/leg we want the status of | |
1302 | * | |
1303 | * We return one character representing the most severe error | |
1304 | * we have encountered. | |
1305 | * A => Alive - No failures | |
1306 | * D => Dead - A write failure occurred leaving mirror out-of-sync | |
1307 | * S => Sync - A sychronization failure occurred, mirror out-of-sync | |
1308 | * R => Read - A read failure occurred, mirror data unaffected | |
1309 | * | |
1310 | * Returns: <char> | |
1311 | */ | |
1312 | static char device_status_char(struct mirror *m) | |
1313 | { | |
1314 | if (!atomic_read(&(m->error_count))) | |
1315 | return 'A'; | |
1316 | ||
64b30c46 MP |
1317 | return (test_bit(DM_RAID1_FLUSH_ERROR, &(m->error_type))) ? 'F' : |
1318 | (test_bit(DM_RAID1_WRITE_ERROR, &(m->error_type))) ? 'D' : | |
af195ac8 JB |
1319 | (test_bit(DM_RAID1_SYNC_ERROR, &(m->error_type))) ? 'S' : |
1320 | (test_bit(DM_RAID1_READ_ERROR, &(m->error_type))) ? 'R' : 'U'; | |
1321 | } | |
1322 | ||
1323 | ||
1da177e4 LT |
1324 | static int mirror_status(struct dm_target *ti, status_type_t type, |
1325 | char *result, unsigned int maxlen) | |
1326 | { | |
315dcc22 | 1327 | unsigned int m, sz = 0; |
1da177e4 | 1328 | struct mirror_set *ms = (struct mirror_set *) ti->private; |
1f965b19 | 1329 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
af195ac8 | 1330 | char buffer[ms->nr_mirrors + 1]; |
1da177e4 | 1331 | |
1da177e4 LT |
1332 | switch (type) { |
1333 | case STATUSTYPE_INFO: | |
1334 | DMEMIT("%d ", ms->nr_mirrors); | |
af195ac8 | 1335 | for (m = 0; m < ms->nr_mirrors; m++) { |
1da177e4 | 1336 | DMEMIT("%s ", ms->mirror[m].dev->name); |
af195ac8 JB |
1337 | buffer[m] = device_status_char(&(ms->mirror[m])); |
1338 | } | |
1339 | buffer[m] = '\0'; | |
1da177e4 | 1340 | |
af195ac8 | 1341 | DMEMIT("%llu/%llu 1 %s ", |
1f965b19 | 1342 | (unsigned long long)log->type->get_sync_count(log), |
af195ac8 | 1343 | (unsigned long long)ms->nr_regions, buffer); |
315dcc22 | 1344 | |
1f965b19 | 1345 | sz += log->type->status(log, type, result+sz, maxlen-sz); |
315dcc22 | 1346 | |
1da177e4 LT |
1347 | break; |
1348 | ||
1349 | case STATUSTYPE_TABLE: | |
1f965b19 | 1350 | sz = log->type->status(log, type, result, maxlen); |
315dcc22 | 1351 | |
e52b8f6d | 1352 | DMEMIT("%d", ms->nr_mirrors); |
1da177e4 | 1353 | for (m = 0; m < ms->nr_mirrors; m++) |
e52b8f6d | 1354 | DMEMIT(" %s %llu", ms->mirror[m].dev->name, |
b80aa7a0 | 1355 | (unsigned long long)ms->mirror[m].offset); |
a8e6afa2 JB |
1356 | |
1357 | if (ms->features & DM_RAID1_HANDLE_ERRORS) | |
1358 | DMEMIT(" 1 handle_errors"); | |
1da177e4 LT |
1359 | } |
1360 | ||
1361 | return 0; | |
1362 | } | |
1363 | ||
af4874e0 MS |
1364 | static int mirror_iterate_devices(struct dm_target *ti, |
1365 | iterate_devices_callout_fn fn, void *data) | |
1366 | { | |
1367 | struct mirror_set *ms = ti->private; | |
1368 | int ret = 0; | |
1369 | unsigned i; | |
1370 | ||
1371 | for (i = 0; !ret && i < ms->nr_mirrors; i++) | |
1372 | ret = fn(ti, ms->mirror[i].dev, | |
5dea271b | 1373 | ms->mirror[i].offset, ti->len, data); |
af4874e0 MS |
1374 | |
1375 | return ret; | |
1376 | } | |
1377 | ||
1da177e4 LT |
1378 | static struct target_type mirror_target = { |
1379 | .name = "mirror", | |
af4874e0 | 1380 | .version = {1, 12, 0}, |
1da177e4 LT |
1381 | .module = THIS_MODULE, |
1382 | .ctr = mirror_ctr, | |
1383 | .dtr = mirror_dtr, | |
1384 | .map = mirror_map, | |
1385 | .end_io = mirror_end_io, | |
b80aa7a0 | 1386 | .presuspend = mirror_presuspend, |
1da177e4 LT |
1387 | .postsuspend = mirror_postsuspend, |
1388 | .resume = mirror_resume, | |
1389 | .status = mirror_status, | |
af4874e0 | 1390 | .iterate_devices = mirror_iterate_devices, |
1da177e4 LT |
1391 | }; |
1392 | ||
1393 | static int __init dm_mirror_init(void) | |
1394 | { | |
1395 | int r; | |
1396 | ||
95f8fac8 MP |
1397 | _dm_raid1_read_record_cache = KMEM_CACHE(dm_raid1_read_record, 0); |
1398 | if (!_dm_raid1_read_record_cache) { | |
1399 | DMERR("Can't allocate dm_raid1_read_record cache"); | |
1400 | r = -ENOMEM; | |
1401 | goto bad_cache; | |
1402 | } | |
1403 | ||
1da177e4 | 1404 | r = dm_register_target(&mirror_target); |
95f8fac8 | 1405 | if (r < 0) { |
0cd33124 | 1406 | DMERR("Failed to register mirror target"); |
95f8fac8 MP |
1407 | goto bad_target; |
1408 | } | |
1409 | ||
1410 | return 0; | |
1da177e4 | 1411 | |
95f8fac8 MP |
1412 | bad_target: |
1413 | kmem_cache_destroy(_dm_raid1_read_record_cache); | |
1414 | bad_cache: | |
1da177e4 LT |
1415 | return r; |
1416 | } | |
1417 | ||
1418 | static void __exit dm_mirror_exit(void) | |
1419 | { | |
10d3bd09 | 1420 | dm_unregister_target(&mirror_target); |
95f8fac8 | 1421 | kmem_cache_destroy(_dm_raid1_read_record_cache); |
1da177e4 LT |
1422 | } |
1423 | ||
1424 | /* Module hooks */ | |
1425 | module_init(dm_mirror_init); | |
1426 | module_exit(dm_mirror_exit); | |
1427 | ||
1428 | MODULE_DESCRIPTION(DM_NAME " mirror target"); | |
1429 | MODULE_AUTHOR("Joe Thornber"); | |
1430 | MODULE_LICENSE("GPL"); |