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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. */ | |
72d94861 | 25 | |
65972a6f KC |
26 | #define MAX_NR_MIRRORS (DM_KCOPYD_MAX_REGIONS + 1) |
27 | ||
ed63287d LZ |
28 | #define DM_RAID1_HANDLE_ERRORS 0x01 |
29 | #define DM_RAID1_KEEP_LOG 0x02 | |
f44db678 | 30 | #define errors_handled(p) ((p)->features & DM_RAID1_HANDLE_ERRORS) |
ed63287d | 31 | #define keep_log(p) ((p)->features & DM_RAID1_KEEP_LOG) |
a8e6afa2 | 32 | |
33184048 | 33 | static DECLARE_WAIT_QUEUE_HEAD(_kmirrord_recovery_stopped); |
1da177e4 | 34 | |
e4c8b3ba NB |
35 | /*----------------------------------------------------------------- |
36 | * Mirror set structures. | |
37 | *---------------------------------------------------------------*/ | |
72f4b314 JB |
38 | enum dm_raid1_error { |
39 | DM_RAID1_WRITE_ERROR, | |
64b30c46 | 40 | DM_RAID1_FLUSH_ERROR, |
72f4b314 JB |
41 | DM_RAID1_SYNC_ERROR, |
42 | DM_RAID1_READ_ERROR | |
43 | }; | |
44 | ||
e4c8b3ba | 45 | struct mirror { |
aa5617c5 | 46 | struct mirror_set *ms; |
e4c8b3ba | 47 | atomic_t error_count; |
39ed7adb | 48 | unsigned long error_type; |
e4c8b3ba NB |
49 | struct dm_dev *dev; |
50 | sector_t offset; | |
51 | }; | |
52 | ||
53 | struct mirror_set { | |
54 | struct dm_target *ti; | |
55 | struct list_head list; | |
1f965b19 | 56 | |
a8e6afa2 | 57 | uint64_t features; |
e4c8b3ba | 58 | |
72f4b314 | 59 | spinlock_t lock; /* protects the lists */ |
e4c8b3ba NB |
60 | struct bio_list reads; |
61 | struct bio_list writes; | |
72f4b314 | 62 | struct bio_list failures; |
04788507 | 63 | struct bio_list holds; /* bios are waiting until suspend */ |
e4c8b3ba | 64 | |
1f965b19 HM |
65 | struct dm_region_hash *rh; |
66 | struct dm_kcopyd_client *kcopyd_client; | |
88be163a MB |
67 | struct dm_io_client *io_client; |
68 | ||
e4c8b3ba NB |
69 | /* recovery */ |
70 | region_t nr_regions; | |
71 | int in_sync; | |
fc1ff958 | 72 | int log_failure; |
929be8fc | 73 | int leg_failure; |
b80aa7a0 | 74 | atomic_t suspend; |
e4c8b3ba | 75 | |
72f4b314 | 76 | atomic_t default_mirror; /* Default mirror */ |
e4c8b3ba | 77 | |
6ad36fe2 HS |
78 | struct workqueue_struct *kmirrord_wq; |
79 | struct work_struct kmirrord_work; | |
a2aebe03 MP |
80 | struct timer_list timer; |
81 | unsigned long timer_pending; | |
82 | ||
72f4b314 | 83 | struct work_struct trigger_event; |
6ad36fe2 | 84 | |
1f965b19 | 85 | unsigned nr_mirrors; |
b18ae8dd | 86 | struct mirror mirror[]; |
e4c8b3ba NB |
87 | }; |
88 | ||
df5d2e90 MP |
89 | DECLARE_DM_KCOPYD_THROTTLE_WITH_MODULE_PARM(raid1_resync_throttle, |
90 | "A percentage of time allocated for raid resynchronization"); | |
91 | ||
1f965b19 | 92 | static void wakeup_mirrord(void *context) |
1da177e4 | 93 | { |
1f965b19 | 94 | struct mirror_set *ms = context; |
1da177e4 | 95 | |
6ad36fe2 HS |
96 | queue_work(ms->kmirrord_wq, &ms->kmirrord_work); |
97 | } | |
98 | ||
8376d3c1 | 99 | static void delayed_wake_fn(struct timer_list *t) |
a2aebe03 | 100 | { |
8376d3c1 | 101 | struct mirror_set *ms = from_timer(ms, t, timer); |
a2aebe03 MP |
102 | |
103 | clear_bit(0, &ms->timer_pending); | |
1f965b19 | 104 | wakeup_mirrord(ms); |
a2aebe03 MP |
105 | } |
106 | ||
107 | static void delayed_wake(struct mirror_set *ms) | |
108 | { | |
109 | if (test_and_set_bit(0, &ms->timer_pending)) | |
110 | return; | |
111 | ||
112 | ms->timer.expires = jiffies + HZ / 5; | |
a2aebe03 MP |
113 | add_timer(&ms->timer); |
114 | } | |
115 | ||
1f965b19 | 116 | static void wakeup_all_recovery_waiters(void *context) |
1da177e4 | 117 | { |
1f965b19 | 118 | wake_up_all(&_kmirrord_recovery_stopped); |
1da177e4 LT |
119 | } |
120 | ||
1f965b19 | 121 | static void queue_bio(struct mirror_set *ms, struct bio *bio, int rw) |
1da177e4 LT |
122 | { |
123 | unsigned long flags; | |
1da177e4 | 124 | int should_wake = 0; |
1f965b19 | 125 | struct bio_list *bl; |
1da177e4 | 126 | |
1f965b19 HM |
127 | bl = (rw == WRITE) ? &ms->writes : &ms->reads; |
128 | spin_lock_irqsave(&ms->lock, flags); | |
129 | should_wake = !(bl->head); | |
130 | bio_list_add(bl, bio); | |
131 | spin_unlock_irqrestore(&ms->lock, flags); | |
1da177e4 LT |
132 | |
133 | if (should_wake) | |
1f965b19 | 134 | wakeup_mirrord(ms); |
1da177e4 LT |
135 | } |
136 | ||
1f965b19 | 137 | static void dispatch_bios(void *context, struct bio_list *bio_list) |
1da177e4 | 138 | { |
1f965b19 HM |
139 | struct mirror_set *ms = context; |
140 | struct bio *bio; | |
1da177e4 | 141 | |
1f965b19 HM |
142 | while ((bio = bio_list_pop(bio_list))) |
143 | queue_bio(ms, bio, WRITE); | |
1da177e4 LT |
144 | } |
145 | ||
89c7cd89 | 146 | struct dm_raid1_bio_record { |
06386bbf | 147 | struct mirror *m; |
74d46992 | 148 | /* if details->bi_disk == NULL, details were not saved */ |
06386bbf | 149 | struct dm_bio_details details; |
0045d61b | 150 | region_t write_region; |
06386bbf JB |
151 | }; |
152 | ||
1da177e4 LT |
153 | /* |
154 | * Every mirror should look like this one. | |
155 | */ | |
156 | #define DEFAULT_MIRROR 0 | |
157 | ||
158 | /* | |
06386bbf JB |
159 | * This is yucky. We squirrel the mirror struct away inside |
160 | * bi_next for read/write buffers. This is safe since the bh | |
1da177e4 LT |
161 | * doesn't get submitted to the lower levels of block layer. |
162 | */ | |
06386bbf | 163 | static struct mirror *bio_get_m(struct bio *bio) |
1da177e4 | 164 | { |
06386bbf | 165 | return (struct mirror *) bio->bi_next; |
1da177e4 LT |
166 | } |
167 | ||
06386bbf | 168 | static void bio_set_m(struct bio *bio, struct mirror *m) |
1da177e4 | 169 | { |
06386bbf | 170 | bio->bi_next = (struct bio *) m; |
1da177e4 LT |
171 | } |
172 | ||
72f4b314 JB |
173 | static struct mirror *get_default_mirror(struct mirror_set *ms) |
174 | { | |
175 | return &ms->mirror[atomic_read(&ms->default_mirror)]; | |
176 | } | |
177 | ||
178 | static void set_default_mirror(struct mirror *m) | |
179 | { | |
180 | struct mirror_set *ms = m->ms; | |
181 | struct mirror *m0 = &(ms->mirror[0]); | |
182 | ||
183 | atomic_set(&ms->default_mirror, m - m0); | |
184 | } | |
185 | ||
87968ddd MP |
186 | static struct mirror *get_valid_mirror(struct mirror_set *ms) |
187 | { | |
188 | struct mirror *m; | |
189 | ||
190 | for (m = ms->mirror; m < ms->mirror + ms->nr_mirrors; m++) | |
191 | if (!atomic_read(&m->error_count)) | |
192 | return m; | |
193 | ||
194 | return NULL; | |
195 | } | |
196 | ||
72f4b314 JB |
197 | /* fail_mirror |
198 | * @m: mirror device to fail | |
199 | * @error_type: one of the enum's, DM_RAID1_*_ERROR | |
200 | * | |
201 | * If errors are being handled, record the type of | |
202 | * error encountered for this device. If this type | |
203 | * of error has already been recorded, we can return; | |
204 | * otherwise, we must signal userspace by triggering | |
205 | * an event. Additionally, if the device is the | |
206 | * primary device, we must choose a new primary, but | |
207 | * only if the mirror is in-sync. | |
208 | * | |
209 | * This function must not block. | |
210 | */ | |
211 | static void fail_mirror(struct mirror *m, enum dm_raid1_error error_type) | |
212 | { | |
213 | struct mirror_set *ms = m->ms; | |
214 | struct mirror *new; | |
215 | ||
929be8fc MP |
216 | ms->leg_failure = 1; |
217 | ||
72f4b314 JB |
218 | /* |
219 | * error_count is used for nothing more than a | |
220 | * simple way to tell if a device has encountered | |
221 | * errors. | |
222 | */ | |
223 | atomic_inc(&m->error_count); | |
224 | ||
225 | if (test_and_set_bit(error_type, &m->error_type)) | |
226 | return; | |
227 | ||
d460c65a JB |
228 | if (!errors_handled(ms)) |
229 | return; | |
230 | ||
72f4b314 JB |
231 | if (m != get_default_mirror(ms)) |
232 | goto out; | |
233 | ||
ed63287d | 234 | if (!ms->in_sync && !keep_log(ms)) { |
72f4b314 JB |
235 | /* |
236 | * Better to issue requests to same failing device | |
237 | * than to risk returning corrupt data. | |
238 | */ | |
239 | DMERR("Primary mirror (%s) failed while out-of-sync: " | |
240 | "Reads may fail.", m->dev->name); | |
241 | goto out; | |
242 | } | |
243 | ||
87968ddd MP |
244 | new = get_valid_mirror(ms); |
245 | if (new) | |
246 | set_default_mirror(new); | |
247 | else | |
72f4b314 JB |
248 | DMWARN("All sides of mirror have failed."); |
249 | ||
250 | out: | |
251 | schedule_work(&ms->trigger_event); | |
252 | } | |
253 | ||
c0da3748 MP |
254 | static int mirror_flush(struct dm_target *ti) |
255 | { | |
256 | struct mirror_set *ms = ti->private; | |
257 | unsigned long error_bits; | |
258 | ||
259 | unsigned int i; | |
65972a6f | 260 | struct dm_io_region io[MAX_NR_MIRRORS]; |
c0da3748 MP |
261 | struct mirror *m; |
262 | struct dm_io_request io_req = { | |
e6047149 | 263 | .bi_op = REQ_OP_WRITE, |
ff0361b3 | 264 | .bi_op_flags = REQ_PREFLUSH | REQ_SYNC, |
c0da3748 | 265 | .mem.type = DM_IO_KMEM, |
5fc2ffea | 266 | .mem.ptr.addr = NULL, |
c0da3748 MP |
267 | .client = ms->io_client, |
268 | }; | |
269 | ||
270 | for (i = 0, m = ms->mirror; i < ms->nr_mirrors; i++, m++) { | |
271 | io[i].bdev = m->dev->bdev; | |
272 | io[i].sector = 0; | |
273 | io[i].count = 0; | |
274 | } | |
275 | ||
276 | error_bits = -1; | |
277 | dm_io(&io_req, ms->nr_mirrors, io, &error_bits); | |
278 | if (unlikely(error_bits != 0)) { | |
279 | for (i = 0; i < ms->nr_mirrors; i++) | |
280 | if (test_bit(i, &error_bits)) | |
281 | fail_mirror(ms->mirror + i, | |
64b30c46 | 282 | DM_RAID1_FLUSH_ERROR); |
c0da3748 MP |
283 | return -EIO; |
284 | } | |
285 | ||
286 | return 0; | |
287 | } | |
288 | ||
1da177e4 LT |
289 | /*----------------------------------------------------------------- |
290 | * Recovery. | |
291 | * | |
292 | * When a mirror is first activated we may find that some regions | |
293 | * are in the no-sync state. We have to recover these by | |
294 | * recopying from the default mirror to all the others. | |
295 | *---------------------------------------------------------------*/ | |
4cdc1d1f | 296 | static void recovery_complete(int read_err, unsigned long write_err, |
1da177e4 LT |
297 | void *context) |
298 | { | |
1f965b19 HM |
299 | struct dm_region *reg = context; |
300 | struct mirror_set *ms = dm_rh_region_context(reg); | |
8f0205b7 | 301 | int m, bit = 0; |
1da177e4 | 302 | |
8f0205b7 | 303 | if (read_err) { |
f44db678 JB |
304 | /* Read error means the failure of default mirror. */ |
305 | DMERR_LIMIT("Unable to read primary mirror during recovery"); | |
8f0205b7 JB |
306 | fail_mirror(get_default_mirror(ms), DM_RAID1_SYNC_ERROR); |
307 | } | |
f44db678 | 308 | |
8f0205b7 | 309 | if (write_err) { |
4cdc1d1f | 310 | DMERR_LIMIT("Write error during recovery (error = 0x%lx)", |
f44db678 | 311 | write_err); |
8f0205b7 JB |
312 | /* |
313 | * Bits correspond to devices (excluding default mirror). | |
314 | * The default mirror cannot change during recovery. | |
315 | */ | |
316 | for (m = 0; m < ms->nr_mirrors; m++) { | |
317 | if (&ms->mirror[m] == get_default_mirror(ms)) | |
318 | continue; | |
319 | if (test_bit(bit, &write_err)) | |
320 | fail_mirror(ms->mirror + m, | |
321 | DM_RAID1_SYNC_ERROR); | |
322 | bit++; | |
323 | } | |
324 | } | |
f44db678 | 325 | |
1f965b19 | 326 | dm_rh_recovery_end(reg, !(read_err || write_err)); |
1da177e4 LT |
327 | } |
328 | ||
7209049d | 329 | static void recover(struct mirror_set *ms, struct dm_region *reg) |
1da177e4 | 330 | { |
1f965b19 | 331 | unsigned i; |
eb69aca5 | 332 | struct dm_io_region from, to[DM_KCOPYD_MAX_REGIONS], *dest; |
1da177e4 LT |
333 | struct mirror *m; |
334 | unsigned long flags = 0; | |
1f965b19 HM |
335 | region_t key = dm_rh_get_region_key(reg); |
336 | sector_t region_size = dm_rh_get_region_size(ms->rh); | |
1da177e4 LT |
337 | |
338 | /* fill in the source */ | |
72f4b314 | 339 | m = get_default_mirror(ms); |
1da177e4 | 340 | from.bdev = m->dev->bdev; |
1f965b19 HM |
341 | from.sector = m->offset + dm_rh_region_to_sector(ms->rh, key); |
342 | if (key == (ms->nr_regions - 1)) { | |
1da177e4 LT |
343 | /* |
344 | * The final region may be smaller than | |
345 | * region_size. | |
346 | */ | |
1f965b19 | 347 | from.count = ms->ti->len & (region_size - 1); |
1da177e4 | 348 | if (!from.count) |
1f965b19 | 349 | from.count = region_size; |
1da177e4 | 350 | } else |
1f965b19 | 351 | from.count = region_size; |
1da177e4 LT |
352 | |
353 | /* fill in the destinations */ | |
354 | for (i = 0, dest = to; i < ms->nr_mirrors; i++) { | |
72f4b314 | 355 | if (&ms->mirror[i] == get_default_mirror(ms)) |
1da177e4 LT |
356 | continue; |
357 | ||
358 | m = ms->mirror + i; | |
359 | dest->bdev = m->dev->bdev; | |
1f965b19 | 360 | dest->sector = m->offset + dm_rh_region_to_sector(ms->rh, key); |
1da177e4 LT |
361 | dest->count = from.count; |
362 | dest++; | |
363 | } | |
364 | ||
365 | /* hand to kcopyd */ | |
f7c83e2e JB |
366 | if (!errors_handled(ms)) |
367 | set_bit(DM_KCOPYD_IGNORE_ERROR, &flags); | |
368 | ||
7209049d MS |
369 | dm_kcopyd_copy(ms->kcopyd_client, &from, ms->nr_mirrors - 1, to, |
370 | flags, recovery_complete, reg); | |
1da177e4 LT |
371 | } |
372 | ||
ed63287d LZ |
373 | static void reset_ms_flags(struct mirror_set *ms) |
374 | { | |
375 | unsigned int m; | |
376 | ||
377 | ms->leg_failure = 0; | |
378 | for (m = 0; m < ms->nr_mirrors; m++) { | |
379 | atomic_set(&(ms->mirror[m].error_count), 0); | |
380 | ms->mirror[m].error_type = 0; | |
381 | } | |
382 | } | |
383 | ||
1da177e4 LT |
384 | static void do_recovery(struct mirror_set *ms) |
385 | { | |
1f965b19 HM |
386 | struct dm_region *reg; |
387 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); | |
1da177e4 LT |
388 | |
389 | /* | |
390 | * Start quiescing some regions. | |
391 | */ | |
1f965b19 | 392 | dm_rh_recovery_prepare(ms->rh); |
1da177e4 LT |
393 | |
394 | /* | |
395 | * Copy any already quiesced regions. | |
396 | */ | |
7209049d MS |
397 | while ((reg = dm_rh_recovery_start(ms->rh))) |
398 | recover(ms, reg); | |
1da177e4 LT |
399 | |
400 | /* | |
401 | * Update the in sync flag. | |
402 | */ | |
403 | if (!ms->in_sync && | |
404 | (log->type->get_sync_count(log) == ms->nr_regions)) { | |
405 | /* the sync is complete */ | |
406 | dm_table_event(ms->ti->table); | |
407 | ms->in_sync = 1; | |
ed63287d | 408 | reset_ms_flags(ms); |
1da177e4 LT |
409 | } |
410 | } | |
411 | ||
412 | /*----------------------------------------------------------------- | |
413 | * Reads | |
414 | *---------------------------------------------------------------*/ | |
415 | static struct mirror *choose_mirror(struct mirror_set *ms, sector_t sector) | |
416 | { | |
06386bbf JB |
417 | struct mirror *m = get_default_mirror(ms); |
418 | ||
419 | do { | |
420 | if (likely(!atomic_read(&m->error_count))) | |
421 | return m; | |
422 | ||
423 | if (m-- == ms->mirror) | |
424 | m += ms->nr_mirrors; | |
425 | } while (m != get_default_mirror(ms)); | |
426 | ||
427 | return NULL; | |
428 | } | |
429 | ||
430 | static int default_ok(struct mirror *m) | |
431 | { | |
432 | struct mirror *default_mirror = get_default_mirror(m->ms); | |
433 | ||
434 | return !atomic_read(&default_mirror->error_count); | |
435 | } | |
436 | ||
437 | static int mirror_available(struct mirror_set *ms, struct bio *bio) | |
438 | { | |
1f965b19 HM |
439 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
440 | region_t region = dm_rh_bio_to_region(ms->rh, bio); | |
06386bbf | 441 | |
1f965b19 | 442 | if (log->type->in_sync(log, region, 0)) |
4f024f37 | 443 | return choose_mirror(ms, bio->bi_iter.bi_sector) ? 1 : 0; |
06386bbf JB |
444 | |
445 | return 0; | |
1da177e4 LT |
446 | } |
447 | ||
448 | /* | |
449 | * remap a buffer to a particular mirror. | |
450 | */ | |
06386bbf JB |
451 | static sector_t map_sector(struct mirror *m, struct bio *bio) |
452 | { | |
4f024f37 | 453 | if (unlikely(!bio->bi_iter.bi_size)) |
4184153f | 454 | return 0; |
4f024f37 | 455 | return m->offset + dm_target_offset(m->ms->ti, bio->bi_iter.bi_sector); |
06386bbf JB |
456 | } |
457 | ||
458 | static void map_bio(struct mirror *m, struct bio *bio) | |
1da177e4 | 459 | { |
74d46992 | 460 | bio_set_dev(bio, m->dev->bdev); |
4f024f37 | 461 | bio->bi_iter.bi_sector = map_sector(m, bio); |
06386bbf JB |
462 | } |
463 | ||
22a1ceb1 | 464 | static void map_region(struct dm_io_region *io, struct mirror *m, |
06386bbf JB |
465 | struct bio *bio) |
466 | { | |
467 | io->bdev = m->dev->bdev; | |
468 | io->sector = map_sector(m, bio); | |
aa8b57aa | 469 | io->count = bio_sectors(bio); |
06386bbf JB |
470 | } |
471 | ||
04788507 MP |
472 | static void hold_bio(struct mirror_set *ms, struct bio *bio) |
473 | { | |
474 | /* | |
f0703040 TY |
475 | * Lock is required to avoid race condition during suspend |
476 | * process. | |
04788507 | 477 | */ |
f0703040 TY |
478 | spin_lock_irq(&ms->lock); |
479 | ||
04788507 | 480 | if (atomic_read(&ms->suspend)) { |
f0703040 TY |
481 | spin_unlock_irq(&ms->lock); |
482 | ||
483 | /* | |
484 | * If device is suspended, complete the bio. | |
485 | */ | |
04788507 | 486 | if (dm_noflush_suspending(ms->ti)) |
4e4cbee9 | 487 | bio->bi_status = BLK_STS_DM_REQUEUE; |
04788507 | 488 | else |
4e4cbee9 | 489 | bio->bi_status = BLK_STS_IOERR; |
4246a0b6 CH |
490 | |
491 | bio_endio(bio); | |
04788507 MP |
492 | return; |
493 | } | |
494 | ||
495 | /* | |
496 | * Hold bio until the suspend is complete. | |
497 | */ | |
04788507 MP |
498 | bio_list_add(&ms->holds, bio); |
499 | spin_unlock_irq(&ms->lock); | |
500 | } | |
501 | ||
06386bbf JB |
502 | /*----------------------------------------------------------------- |
503 | * Reads | |
504 | *---------------------------------------------------------------*/ | |
505 | static void read_callback(unsigned long error, void *context) | |
506 | { | |
507 | struct bio *bio = context; | |
508 | struct mirror *m; | |
509 | ||
510 | m = bio_get_m(bio); | |
511 | bio_set_m(bio, NULL); | |
512 | ||
513 | if (likely(!error)) { | |
4246a0b6 | 514 | bio_endio(bio); |
06386bbf JB |
515 | return; |
516 | } | |
517 | ||
518 | fail_mirror(m, DM_RAID1_READ_ERROR); | |
519 | ||
520 | if (likely(default_ok(m)) || mirror_available(m->ms, bio)) { | |
521 | DMWARN_LIMIT("Read failure on mirror device %s. " | |
522 | "Trying alternative device.", | |
523 | m->dev->name); | |
70246286 | 524 | queue_bio(m->ms, bio, bio_data_dir(bio)); |
06386bbf JB |
525 | return; |
526 | } | |
527 | ||
528 | DMERR_LIMIT("Read failure on mirror device %s. Failing I/O.", | |
529 | m->dev->name); | |
4246a0b6 | 530 | bio_io_error(bio); |
06386bbf JB |
531 | } |
532 | ||
533 | /* Asynchronous read. */ | |
534 | static void read_async_bio(struct mirror *m, struct bio *bio) | |
535 | { | |
22a1ceb1 | 536 | struct dm_io_region io; |
06386bbf | 537 | struct dm_io_request io_req = { |
e6047149 MC |
538 | .bi_op = REQ_OP_READ, |
539 | .bi_op_flags = 0, | |
003b5c57 KO |
540 | .mem.type = DM_IO_BIO, |
541 | .mem.ptr.bio = bio, | |
06386bbf JB |
542 | .notify.fn = read_callback, |
543 | .notify.context = bio, | |
544 | .client = m->ms->io_client, | |
545 | }; | |
546 | ||
547 | map_region(&io, m, bio); | |
548 | bio_set_m(bio, m); | |
1f965b19 HM |
549 | BUG_ON(dm_io(&io_req, 1, &io, NULL)); |
550 | } | |
551 | ||
552 | static inline int region_in_sync(struct mirror_set *ms, region_t region, | |
553 | int may_block) | |
554 | { | |
555 | int state = dm_rh_get_state(ms->rh, region, may_block); | |
556 | return state == DM_RH_CLEAN || state == DM_RH_DIRTY; | |
1da177e4 LT |
557 | } |
558 | ||
559 | static void do_reads(struct mirror_set *ms, struct bio_list *reads) | |
560 | { | |
561 | region_t region; | |
562 | struct bio *bio; | |
563 | struct mirror *m; | |
564 | ||
565 | while ((bio = bio_list_pop(reads))) { | |
1f965b19 | 566 | region = dm_rh_bio_to_region(ms->rh, bio); |
06386bbf | 567 | m = get_default_mirror(ms); |
1da177e4 LT |
568 | |
569 | /* | |
570 | * We can only read balance if the region is in sync. | |
571 | */ | |
1f965b19 | 572 | if (likely(region_in_sync(ms, region, 1))) |
4f024f37 | 573 | m = choose_mirror(ms, bio->bi_iter.bi_sector); |
06386bbf JB |
574 | else if (m && atomic_read(&m->error_count)) |
575 | m = NULL; | |
1da177e4 | 576 | |
06386bbf JB |
577 | if (likely(m)) |
578 | read_async_bio(m, bio); | |
579 | else | |
4246a0b6 | 580 | bio_io_error(bio); |
1da177e4 LT |
581 | } |
582 | } | |
583 | ||
584 | /*----------------------------------------------------------------- | |
585 | * Writes. | |
586 | * | |
587 | * We do different things with the write io depending on the | |
588 | * state of the region that it's in: | |
589 | * | |
590 | * SYNC: increment pending, use kcopyd to write to *all* mirrors | |
591 | * RECOVERING: delay the io until recovery completes | |
592 | * NOSYNC: increment pending, just write to the default mirror | |
593 | *---------------------------------------------------------------*/ | |
72f4b314 | 594 | |
72f4b314 | 595 | |
1da177e4 LT |
596 | static void write_callback(unsigned long error, void *context) |
597 | { | |
4246a0b6 | 598 | unsigned i; |
1da177e4 LT |
599 | struct bio *bio = (struct bio *) context; |
600 | struct mirror_set *ms; | |
72f4b314 JB |
601 | int should_wake = 0; |
602 | unsigned long flags; | |
1da177e4 | 603 | |
06386bbf JB |
604 | ms = bio_get_m(bio)->ms; |
605 | bio_set_m(bio, NULL); | |
1da177e4 LT |
606 | |
607 | /* | |
608 | * NOTE: We don't decrement the pending count here, | |
609 | * instead it is done by the targets endio function. | |
610 | * This way we handle both writes to SYNC and NOSYNC | |
611 | * regions with the same code. | |
612 | */ | |
60f355ea | 613 | if (likely(!error)) { |
4246a0b6 | 614 | bio_endio(bio); |
60f355ea MP |
615 | return; |
616 | } | |
1da177e4 | 617 | |
f2ed51ac MP |
618 | /* |
619 | * If the bio is discard, return an error, but do not | |
620 | * degrade the array. | |
621 | */ | |
e6047149 | 622 | if (bio_op(bio) == REQ_OP_DISCARD) { |
4e4cbee9 | 623 | bio->bi_status = BLK_STS_NOTSUPP; |
4246a0b6 | 624 | bio_endio(bio); |
f2ed51ac MP |
625 | return; |
626 | } | |
627 | ||
72f4b314 JB |
628 | for (i = 0; i < ms->nr_mirrors; i++) |
629 | if (test_bit(i, &error)) | |
630 | fail_mirror(ms->mirror + i, DM_RAID1_WRITE_ERROR); | |
72f4b314 | 631 | |
60f355ea MP |
632 | /* |
633 | * Need to raise event. Since raising | |
634 | * events can block, we need to do it in | |
635 | * the main thread. | |
636 | */ | |
637 | spin_lock_irqsave(&ms->lock, flags); | |
638 | if (!ms->failures.head) | |
639 | should_wake = 1; | |
640 | bio_list_add(&ms->failures, bio); | |
641 | spin_unlock_irqrestore(&ms->lock, flags); | |
642 | if (should_wake) | |
643 | wakeup_mirrord(ms); | |
1da177e4 LT |
644 | } |
645 | ||
646 | static void do_write(struct mirror_set *ms, struct bio *bio) | |
647 | { | |
648 | unsigned int i; | |
65972a6f | 649 | struct dm_io_region io[MAX_NR_MIRRORS], *dest = io; |
1da177e4 | 650 | struct mirror *m; |
88be163a | 651 | struct dm_io_request io_req = { |
e6047149 | 652 | .bi_op = REQ_OP_WRITE, |
70fd7614 | 653 | .bi_op_flags = bio->bi_opf & (REQ_FUA | REQ_PREFLUSH), |
003b5c57 KO |
654 | .mem.type = DM_IO_BIO, |
655 | .mem.ptr.bio = bio, | |
88be163a MB |
656 | .notify.fn = write_callback, |
657 | .notify.context = bio, | |
658 | .client = ms->io_client, | |
659 | }; | |
1da177e4 | 660 | |
e6047149 MC |
661 | if (bio_op(bio) == REQ_OP_DISCARD) { |
662 | io_req.bi_op = REQ_OP_DISCARD; | |
5fc2ffea MS |
663 | io_req.mem.type = DM_IO_KMEM; |
664 | io_req.mem.ptr.addr = NULL; | |
665 | } | |
666 | ||
06386bbf JB |
667 | for (i = 0, m = ms->mirror; i < ms->nr_mirrors; i++, m++) |
668 | map_region(dest++, m, bio); | |
1da177e4 | 669 | |
06386bbf JB |
670 | /* |
671 | * Use default mirror because we only need it to retrieve the reference | |
672 | * to the mirror set in write_callback(). | |
673 | */ | |
674 | bio_set_m(bio, get_default_mirror(ms)); | |
88be163a | 675 | |
1f965b19 | 676 | BUG_ON(dm_io(&io_req, ms->nr_mirrors, io, NULL)); |
1da177e4 LT |
677 | } |
678 | ||
679 | static void do_writes(struct mirror_set *ms, struct bio_list *writes) | |
680 | { | |
681 | int state; | |
682 | struct bio *bio; | |
683 | struct bio_list sync, nosync, recover, *this_list = NULL; | |
7513c2a7 JB |
684 | struct bio_list requeue; |
685 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); | |
686 | region_t region; | |
1da177e4 LT |
687 | |
688 | if (!writes->head) | |
689 | return; | |
690 | ||
691 | /* | |
692 | * Classify each write. | |
693 | */ | |
694 | bio_list_init(&sync); | |
695 | bio_list_init(&nosync); | |
696 | bio_list_init(&recover); | |
7513c2a7 | 697 | bio_list_init(&requeue); |
1da177e4 LT |
698 | |
699 | while ((bio = bio_list_pop(writes))) { | |
1eff9d32 | 700 | if ((bio->bi_opf & REQ_PREFLUSH) || |
e6047149 | 701 | (bio_op(bio) == REQ_OP_DISCARD)) { |
4184153f MP |
702 | bio_list_add(&sync, bio); |
703 | continue; | |
704 | } | |
705 | ||
7513c2a7 JB |
706 | region = dm_rh_bio_to_region(ms->rh, bio); |
707 | ||
708 | if (log->type->is_remote_recovering && | |
709 | log->type->is_remote_recovering(log, region)) { | |
710 | bio_list_add(&requeue, bio); | |
711 | continue; | |
712 | } | |
713 | ||
714 | state = dm_rh_get_state(ms->rh, region, 1); | |
1da177e4 | 715 | switch (state) { |
1f965b19 HM |
716 | case DM_RH_CLEAN: |
717 | case DM_RH_DIRTY: | |
1da177e4 LT |
718 | this_list = &sync; |
719 | break; | |
720 | ||
1f965b19 | 721 | case DM_RH_NOSYNC: |
1da177e4 LT |
722 | this_list = &nosync; |
723 | break; | |
724 | ||
1f965b19 | 725 | case DM_RH_RECOVERING: |
1da177e4 LT |
726 | this_list = &recover; |
727 | break; | |
728 | } | |
729 | ||
730 | bio_list_add(this_list, bio); | |
731 | } | |
732 | ||
7513c2a7 JB |
733 | /* |
734 | * Add bios that are delayed due to remote recovery | |
735 | * back on to the write queue | |
736 | */ | |
737 | if (unlikely(requeue.head)) { | |
738 | spin_lock_irq(&ms->lock); | |
739 | bio_list_merge(&ms->writes, &requeue); | |
740 | spin_unlock_irq(&ms->lock); | |
69885683 | 741 | delayed_wake(ms); |
7513c2a7 JB |
742 | } |
743 | ||
1da177e4 LT |
744 | /* |
745 | * Increment the pending counts for any regions that will | |
746 | * be written to (writes to recover regions are going to | |
747 | * be delayed). | |
748 | */ | |
1f965b19 HM |
749 | dm_rh_inc_pending(ms->rh, &sync); |
750 | dm_rh_inc_pending(ms->rh, &nosync); | |
d2b69864 JB |
751 | |
752 | /* | |
753 | * If the flush fails on a previous call and succeeds here, | |
754 | * we must not reset the log_failure variable. We need | |
755 | * userspace interaction to do that. | |
756 | */ | |
757 | ms->log_failure = dm_rh_flush(ms->rh) ? 1 : ms->log_failure; | |
1da177e4 LT |
758 | |
759 | /* | |
760 | * Dispatch io. | |
761 | */ | |
5528d17d | 762 | if (unlikely(ms->log_failure) && errors_handled(ms)) { |
b80aa7a0 JB |
763 | spin_lock_irq(&ms->lock); |
764 | bio_list_merge(&ms->failures, &sync); | |
765 | spin_unlock_irq(&ms->lock); | |
1f965b19 | 766 | wakeup_mirrord(ms); |
b80aa7a0 | 767 | } else |
fc1ff958 | 768 | while ((bio = bio_list_pop(&sync))) |
b80aa7a0 | 769 | do_write(ms, bio); |
1da177e4 LT |
770 | |
771 | while ((bio = bio_list_pop(&recover))) | |
1f965b19 | 772 | dm_rh_delay(ms->rh, bio); |
1da177e4 LT |
773 | |
774 | while ((bio = bio_list_pop(&nosync))) { | |
ed63287d | 775 | if (unlikely(ms->leg_failure) && errors_handled(ms) && !keep_log(ms)) { |
ede5ea0b MP |
776 | spin_lock_irq(&ms->lock); |
777 | bio_list_add(&ms->failures, bio); | |
778 | spin_unlock_irq(&ms->lock); | |
779 | wakeup_mirrord(ms); | |
780 | } else { | |
929be8fc MP |
781 | map_bio(get_default_mirror(ms), bio); |
782 | generic_make_request(bio); | |
783 | } | |
1da177e4 LT |
784 | } |
785 | } | |
786 | ||
72f4b314 JB |
787 | static void do_failures(struct mirror_set *ms, struct bio_list *failures) |
788 | { | |
789 | struct bio *bio; | |
790 | ||
0f398a84 | 791 | if (likely(!failures->head)) |
72f4b314 JB |
792 | return; |
793 | ||
b80aa7a0 JB |
794 | /* |
795 | * If the log has failed, unattempted writes are being | |
0f398a84 | 796 | * put on the holds list. We can't issue those writes |
b80aa7a0 JB |
797 | * until a log has been marked, so we must store them. |
798 | * | |
799 | * If a 'noflush' suspend is in progress, we can requeue | |
800 | * the I/O's to the core. This give userspace a chance | |
801 | * to reconfigure the mirror, at which point the core | |
802 | * will reissue the writes. If the 'noflush' flag is | |
803 | * not set, we have no choice but to return errors. | |
804 | * | |
805 | * Some writes on the failures list may have been | |
806 | * submitted before the log failure and represent a | |
807 | * failure to write to one of the devices. It is ok | |
808 | * for us to treat them the same and requeue them | |
809 | * as well. | |
810 | */ | |
0f398a84 | 811 | while ((bio = bio_list_pop(failures))) { |
60f355ea | 812 | if (!ms->log_failure) { |
0f398a84 | 813 | ms->in_sync = 0; |
c58098be | 814 | dm_rh_mark_nosync(ms->rh, bio); |
0f398a84 | 815 | } |
60f355ea MP |
816 | |
817 | /* | |
818 | * If all the legs are dead, fail the I/O. | |
ed63287d LZ |
819 | * If the device has failed and keep_log is enabled, |
820 | * fail the I/O. | |
821 | * | |
822 | * If we have been told to handle errors, and keep_log | |
823 | * isn't enabled, hold the bio and wait for userspace to | |
824 | * deal with the problem. | |
825 | * | |
60f355ea MP |
826 | * Otherwise pretend that the I/O succeeded. (This would |
827 | * be wrong if the failed leg returned after reboot and | |
828 | * got replicated back to the good legs.) | |
829 | */ | |
ed63287d | 830 | if (unlikely(!get_valid_mirror(ms) || (keep_log(ms) && ms->log_failure))) |
4246a0b6 | 831 | bio_io_error(bio); |
ed63287d | 832 | else if (errors_handled(ms) && !keep_log(ms)) |
60f355ea MP |
833 | hold_bio(ms, bio); |
834 | else | |
4246a0b6 | 835 | bio_endio(bio); |
b80aa7a0 | 836 | } |
72f4b314 JB |
837 | } |
838 | ||
839 | static void trigger_event(struct work_struct *work) | |
840 | { | |
841 | struct mirror_set *ms = | |
842 | container_of(work, struct mirror_set, trigger_event); | |
843 | ||
844 | dm_table_event(ms->ti->table); | |
845 | } | |
846 | ||
1da177e4 LT |
847 | /*----------------------------------------------------------------- |
848 | * kmirrord | |
849 | *---------------------------------------------------------------*/ | |
a2aebe03 | 850 | static void do_mirror(struct work_struct *work) |
1da177e4 | 851 | { |
1f965b19 HM |
852 | struct mirror_set *ms = container_of(work, struct mirror_set, |
853 | kmirrord_work); | |
72f4b314 JB |
854 | struct bio_list reads, writes, failures; |
855 | unsigned long flags; | |
1da177e4 | 856 | |
72f4b314 | 857 | spin_lock_irqsave(&ms->lock, flags); |
1da177e4 LT |
858 | reads = ms->reads; |
859 | writes = ms->writes; | |
72f4b314 | 860 | failures = ms->failures; |
1da177e4 LT |
861 | bio_list_init(&ms->reads); |
862 | bio_list_init(&ms->writes); | |
72f4b314 JB |
863 | bio_list_init(&ms->failures); |
864 | spin_unlock_irqrestore(&ms->lock, flags); | |
1da177e4 | 865 | |
1f965b19 | 866 | dm_rh_update_states(ms->rh, errors_handled(ms)); |
1da177e4 LT |
867 | do_recovery(ms); |
868 | do_reads(ms, &reads); | |
869 | do_writes(ms, &writes); | |
72f4b314 | 870 | do_failures(ms, &failures); |
1da177e4 LT |
871 | } |
872 | ||
1da177e4 LT |
873 | /*----------------------------------------------------------------- |
874 | * Target functions | |
875 | *---------------------------------------------------------------*/ | |
876 | static struct mirror_set *alloc_context(unsigned int nr_mirrors, | |
877 | uint32_t region_size, | |
878 | struct dm_target *ti, | |
416cd17b | 879 | struct dm_dirty_log *dl) |
1da177e4 | 880 | { |
bcd67654 GS |
881 | struct mirror_set *ms = |
882 | kzalloc(struct_size(ms, mirror, nr_mirrors), GFP_KERNEL); | |
1da177e4 | 883 | |
1da177e4 | 884 | if (!ms) { |
72d94861 | 885 | ti->error = "Cannot allocate mirror context"; |
1da177e4 LT |
886 | return NULL; |
887 | } | |
888 | ||
1da177e4 | 889 | spin_lock_init(&ms->lock); |
5339fc2d MP |
890 | bio_list_init(&ms->reads); |
891 | bio_list_init(&ms->writes); | |
892 | bio_list_init(&ms->failures); | |
893 | bio_list_init(&ms->holds); | |
1da177e4 LT |
894 | |
895 | ms->ti = ti; | |
896 | ms->nr_mirrors = nr_mirrors; | |
897 | ms->nr_regions = dm_sector_div_up(ti->len, region_size); | |
898 | ms->in_sync = 0; | |
b80aa7a0 | 899 | ms->log_failure = 0; |
929be8fc | 900 | ms->leg_failure = 0; |
b80aa7a0 | 901 | atomic_set(&ms->suspend, 0); |
72f4b314 | 902 | atomic_set(&ms->default_mirror, DEFAULT_MIRROR); |
1da177e4 | 903 | |
bda8efec | 904 | ms->io_client = dm_io_client_create(); |
88be163a MB |
905 | if (IS_ERR(ms->io_client)) { |
906 | ti->error = "Error creating dm_io client"; | |
907 | kfree(ms); | |
908 | return NULL; | |
909 | } | |
910 | ||
1f965b19 HM |
911 | ms->rh = dm_region_hash_create(ms, dispatch_bios, wakeup_mirrord, |
912 | wakeup_all_recovery_waiters, | |
913 | ms->ti->begin, MAX_RECOVERY, | |
914 | dl, region_size, ms->nr_regions); | |
915 | if (IS_ERR(ms->rh)) { | |
72d94861 | 916 | ti->error = "Error creating dirty region hash"; |
a72cf737 | 917 | dm_io_client_destroy(ms->io_client); |
1da177e4 LT |
918 | kfree(ms); |
919 | return NULL; | |
920 | } | |
921 | ||
922 | return ms; | |
923 | } | |
924 | ||
925 | static void free_context(struct mirror_set *ms, struct dm_target *ti, | |
926 | unsigned int m) | |
927 | { | |
928 | while (m--) | |
929 | dm_put_device(ti, ms->mirror[m].dev); | |
930 | ||
88be163a | 931 | dm_io_client_destroy(ms->io_client); |
1f965b19 | 932 | dm_region_hash_destroy(ms->rh); |
1da177e4 LT |
933 | kfree(ms); |
934 | } | |
935 | ||
1da177e4 LT |
936 | static int get_mirror(struct mirror_set *ms, struct dm_target *ti, |
937 | unsigned int mirror, char **argv) | |
938 | { | |
4ee218cd | 939 | unsigned long long offset; |
31998ef1 | 940 | char dummy; |
e80d1c80 | 941 | int ret; |
1da177e4 | 942 | |
ef87bfc2 MB |
943 | if (sscanf(argv[1], "%llu%c", &offset, &dummy) != 1 || |
944 | offset != (sector_t)offset) { | |
72d94861 | 945 | ti->error = "Invalid offset"; |
1da177e4 LT |
946 | return -EINVAL; |
947 | } | |
948 | ||
e80d1c80 VG |
949 | ret = dm_get_device(ti, argv[0], dm_table_get_mode(ti->table), |
950 | &ms->mirror[mirror].dev); | |
951 | if (ret) { | |
72d94861 | 952 | ti->error = "Device lookup failure"; |
e80d1c80 | 953 | return ret; |
1da177e4 LT |
954 | } |
955 | ||
aa5617c5 | 956 | ms->mirror[mirror].ms = ms; |
72f4b314 JB |
957 | atomic_set(&(ms->mirror[mirror].error_count), 0); |
958 | ms->mirror[mirror].error_type = 0; | |
1da177e4 LT |
959 | ms->mirror[mirror].offset = offset; |
960 | ||
961 | return 0; | |
962 | } | |
963 | ||
1da177e4 LT |
964 | /* |
965 | * Create dirty log: log_type #log_params <log_params> | |
966 | */ | |
416cd17b | 967 | static struct dm_dirty_log *create_dirty_log(struct dm_target *ti, |
1f965b19 HM |
968 | unsigned argc, char **argv, |
969 | unsigned *args_used) | |
1da177e4 | 970 | { |
1f965b19 | 971 | unsigned param_count; |
416cd17b | 972 | struct dm_dirty_log *dl; |
31998ef1 | 973 | char dummy; |
1da177e4 LT |
974 | |
975 | if (argc < 2) { | |
72d94861 | 976 | ti->error = "Insufficient mirror log arguments"; |
1da177e4 LT |
977 | return NULL; |
978 | } | |
979 | ||
31998ef1 | 980 | if (sscanf(argv[1], "%u%c", ¶m_count, &dummy) != 1) { |
72d94861 | 981 | ti->error = "Invalid mirror log argument count"; |
1da177e4 LT |
982 | return NULL; |
983 | } | |
984 | ||
985 | *args_used = 2 + param_count; | |
986 | ||
987 | if (argc < *args_used) { | |
72d94861 | 988 | ti->error = "Insufficient mirror log arguments"; |
1da177e4 LT |
989 | return NULL; |
990 | } | |
991 | ||
c0da3748 MP |
992 | dl = dm_dirty_log_create(argv[0], ti, mirror_flush, param_count, |
993 | argv + 2); | |
1da177e4 | 994 | if (!dl) { |
72d94861 | 995 | ti->error = "Error creating mirror dirty log"; |
1da177e4 LT |
996 | return NULL; |
997 | } | |
998 | ||
1da177e4 LT |
999 | return dl; |
1000 | } | |
1001 | ||
a8e6afa2 JB |
1002 | static int parse_features(struct mirror_set *ms, unsigned argc, char **argv, |
1003 | unsigned *args_used) | |
1004 | { | |
1005 | unsigned num_features; | |
1006 | struct dm_target *ti = ms->ti; | |
31998ef1 | 1007 | char dummy; |
ed63287d | 1008 | int i; |
a8e6afa2 JB |
1009 | |
1010 | *args_used = 0; | |
1011 | ||
1012 | if (!argc) | |
1013 | return 0; | |
1014 | ||
31998ef1 | 1015 | if (sscanf(argv[0], "%u%c", &num_features, &dummy) != 1) { |
a8e6afa2 JB |
1016 | ti->error = "Invalid number of features"; |
1017 | return -EINVAL; | |
1018 | } | |
1019 | ||
1020 | argc--; | |
1021 | argv++; | |
1022 | (*args_used)++; | |
1023 | ||
1024 | if (num_features > argc) { | |
1025 | ti->error = "Not enough arguments to support feature count"; | |
1026 | return -EINVAL; | |
1027 | } | |
1028 | ||
ed63287d LZ |
1029 | for (i = 0; i < num_features; i++) { |
1030 | if (!strcmp("handle_errors", argv[0])) | |
1031 | ms->features |= DM_RAID1_HANDLE_ERRORS; | |
1032 | else if (!strcmp("keep_log", argv[0])) | |
1033 | ms->features |= DM_RAID1_KEEP_LOG; | |
1034 | else { | |
1035 | ti->error = "Unrecognised feature requested"; | |
1036 | return -EINVAL; | |
1037 | } | |
1038 | ||
1039 | argc--; | |
1040 | argv++; | |
1041 | (*args_used)++; | |
1042 | } | |
1043 | if (!errors_handled(ms) && keep_log(ms)) { | |
1044 | ti->error = "keep_log feature requires the handle_errors feature"; | |
a8e6afa2 JB |
1045 | return -EINVAL; |
1046 | } | |
1047 | ||
a8e6afa2 JB |
1048 | return 0; |
1049 | } | |
1050 | ||
1da177e4 LT |
1051 | /* |
1052 | * Construct a mirror mapping: | |
1053 | * | |
1054 | * log_type #log_params <log_params> | |
1055 | * #mirrors [mirror_path offset]{2,} | |
a8e6afa2 | 1056 | * [#features <features>] |
1da177e4 LT |
1057 | * |
1058 | * log_type is "core" or "disk" | |
1059 | * #log_params is between 1 and 3 | |
a8e6afa2 | 1060 | * |
ed63287d | 1061 | * If present, supported features are "handle_errors" and "keep_log". |
1da177e4 | 1062 | */ |
1da177e4 LT |
1063 | static int mirror_ctr(struct dm_target *ti, unsigned int argc, char **argv) |
1064 | { | |
1065 | int r; | |
1066 | unsigned int nr_mirrors, m, args_used; | |
1067 | struct mirror_set *ms; | |
416cd17b | 1068 | struct dm_dirty_log *dl; |
31998ef1 | 1069 | char dummy; |
1da177e4 LT |
1070 | |
1071 | dl = create_dirty_log(ti, argc, argv, &args_used); | |
1072 | if (!dl) | |
1073 | return -EINVAL; | |
1074 | ||
1075 | argv += args_used; | |
1076 | argc -= args_used; | |
1077 | ||
31998ef1 | 1078 | if (!argc || sscanf(argv[0], "%u%c", &nr_mirrors, &dummy) != 1 || |
65972a6f | 1079 | nr_mirrors < 2 || nr_mirrors > MAX_NR_MIRRORS) { |
72d94861 | 1080 | ti->error = "Invalid number of mirrors"; |
416cd17b | 1081 | dm_dirty_log_destroy(dl); |
1da177e4 LT |
1082 | return -EINVAL; |
1083 | } | |
1084 | ||
1085 | argv++, argc--; | |
1086 | ||
a8e6afa2 JB |
1087 | if (argc < nr_mirrors * 2) { |
1088 | ti->error = "Too few mirror arguments"; | |
416cd17b | 1089 | dm_dirty_log_destroy(dl); |
1da177e4 LT |
1090 | return -EINVAL; |
1091 | } | |
1092 | ||
1093 | ms = alloc_context(nr_mirrors, dl->type->get_region_size(dl), ti, dl); | |
1094 | if (!ms) { | |
416cd17b | 1095 | dm_dirty_log_destroy(dl); |
1da177e4 LT |
1096 | return -ENOMEM; |
1097 | } | |
1098 | ||
1099 | /* Get the mirror parameter sets */ | |
1100 | for (m = 0; m < nr_mirrors; m++) { | |
1101 | r = get_mirror(ms, ti, m, argv); | |
1102 | if (r) { | |
1103 | free_context(ms, ti, m); | |
1104 | return r; | |
1105 | } | |
1106 | argv += 2; | |
1107 | argc -= 2; | |
1108 | } | |
1109 | ||
1110 | ti->private = ms; | |
542f9038 MS |
1111 | |
1112 | r = dm_set_target_max_io_len(ti, dm_rh_get_region_size(ms->rh)); | |
1113 | if (r) | |
1114 | goto err_free_context; | |
1115 | ||
55a62eef AK |
1116 | ti->num_flush_bios = 1; |
1117 | ti->num_discard_bios = 1; | |
30187e1d | 1118 | ti->per_io_data_size = sizeof(struct dm_raid1_bio_record); |
1da177e4 | 1119 | |
670368a8 | 1120 | ms->kmirrord_wq = alloc_workqueue("kmirrord", WQ_MEM_RECLAIM, 0); |
6ad36fe2 HS |
1121 | if (!ms->kmirrord_wq) { |
1122 | DMERR("couldn't start kmirrord"); | |
a72cf737 DM |
1123 | r = -ENOMEM; |
1124 | goto err_free_context; | |
6ad36fe2 HS |
1125 | } |
1126 | INIT_WORK(&ms->kmirrord_work, do_mirror); | |
8376d3c1 | 1127 | timer_setup(&ms->timer, delayed_wake_fn, 0); |
a2aebe03 | 1128 | ms->timer_pending = 0; |
72f4b314 | 1129 | INIT_WORK(&ms->trigger_event, trigger_event); |
6ad36fe2 | 1130 | |
a8e6afa2 | 1131 | r = parse_features(ms, argc, argv, &args_used); |
a72cf737 DM |
1132 | if (r) |
1133 | goto err_destroy_wq; | |
a8e6afa2 JB |
1134 | |
1135 | argv += args_used; | |
1136 | argc -= args_used; | |
1137 | ||
f44db678 JB |
1138 | /* |
1139 | * Any read-balancing addition depends on the | |
1140 | * DM_RAID1_HANDLE_ERRORS flag being present. | |
1141 | * This is because the decision to balance depends | |
1142 | * on the sync state of a region. If the above | |
1143 | * flag is not present, we ignore errors; and | |
1144 | * the sync state may be inaccurate. | |
1145 | */ | |
1146 | ||
a8e6afa2 JB |
1147 | if (argc) { |
1148 | ti->error = "Too many mirror arguments"; | |
a72cf737 DM |
1149 | r = -EINVAL; |
1150 | goto err_destroy_wq; | |
a8e6afa2 JB |
1151 | } |
1152 | ||
df5d2e90 | 1153 | ms->kcopyd_client = dm_kcopyd_client_create(&dm_kcopyd_throttle); |
fa34ce73 MP |
1154 | if (IS_ERR(ms->kcopyd_client)) { |
1155 | r = PTR_ERR(ms->kcopyd_client); | |
a72cf737 | 1156 | goto err_destroy_wq; |
fa34ce73 | 1157 | } |
1da177e4 | 1158 | |
1f965b19 | 1159 | wakeup_mirrord(ms); |
1da177e4 | 1160 | return 0; |
a72cf737 DM |
1161 | |
1162 | err_destroy_wq: | |
1163 | destroy_workqueue(ms->kmirrord_wq); | |
1164 | err_free_context: | |
1165 | free_context(ms, ti, ms->nr_mirrors); | |
1166 | return r; | |
1da177e4 LT |
1167 | } |
1168 | ||
1169 | static void mirror_dtr(struct dm_target *ti) | |
1170 | { | |
1171 | struct mirror_set *ms = (struct mirror_set *) ti->private; | |
1172 | ||
a2aebe03 | 1173 | del_timer_sync(&ms->timer); |
6ad36fe2 | 1174 | flush_workqueue(ms->kmirrord_wq); |
43829731 | 1175 | flush_work(&ms->trigger_event); |
eb69aca5 | 1176 | dm_kcopyd_client_destroy(ms->kcopyd_client); |
6ad36fe2 | 1177 | destroy_workqueue(ms->kmirrord_wq); |
1da177e4 LT |
1178 | free_context(ms, ti, ms->nr_mirrors); |
1179 | } | |
1180 | ||
1da177e4 LT |
1181 | /* |
1182 | * Mirror mapping function | |
1183 | */ | |
7de3ee57 | 1184 | static int mirror_map(struct dm_target *ti, struct bio *bio) |
1da177e4 | 1185 | { |
70246286 | 1186 | int r, rw = bio_data_dir(bio); |
1da177e4 LT |
1187 | struct mirror *m; |
1188 | struct mirror_set *ms = ti->private; | |
1f965b19 | 1189 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
0045d61b MP |
1190 | struct dm_raid1_bio_record *bio_record = |
1191 | dm_per_bio_data(bio, sizeof(struct dm_raid1_bio_record)); | |
1192 | ||
74d46992 | 1193 | bio_record->details.bi_disk = NULL; |
cd15fb64 | 1194 | |
1da177e4 | 1195 | if (rw == WRITE) { |
06386bbf | 1196 | /* Save region for mirror_end_io() handler */ |
0045d61b | 1197 | bio_record->write_region = dm_rh_bio_to_region(ms->rh, bio); |
1da177e4 | 1198 | queue_bio(ms, bio, rw); |
d2a7ad29 | 1199 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
1200 | } |
1201 | ||
1f965b19 | 1202 | r = log->type->in_sync(log, dm_rh_bio_to_region(ms->rh, bio), 0); |
1da177e4 | 1203 | if (r < 0 && r != -EWOULDBLOCK) |
846785e6 | 1204 | return DM_MAPIO_KILL; |
1da177e4 | 1205 | |
1da177e4 | 1206 | /* |
06386bbf | 1207 | * If region is not in-sync queue the bio. |
1da177e4 | 1208 | */ |
06386bbf | 1209 | if (!r || (r == -EWOULDBLOCK)) { |
1eff9d32 | 1210 | if (bio->bi_opf & REQ_RAHEAD) |
846785e6 | 1211 | return DM_MAPIO_KILL; |
1da177e4 | 1212 | |
1da177e4 | 1213 | queue_bio(ms, bio, rw); |
d2a7ad29 | 1214 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
1215 | } |
1216 | ||
06386bbf JB |
1217 | /* |
1218 | * The region is in-sync and we can perform reads directly. | |
1219 | * Store enough information so we can retry if it fails. | |
1220 | */ | |
4f024f37 | 1221 | m = choose_mirror(ms, bio->bi_iter.bi_sector); |
06386bbf | 1222 | if (unlikely(!m)) |
846785e6 | 1223 | return DM_MAPIO_KILL; |
1da177e4 | 1224 | |
89c7cd89 | 1225 | dm_bio_record(&bio_record->details, bio); |
89c7cd89 | 1226 | bio_record->m = m; |
06386bbf JB |
1227 | |
1228 | map_bio(m, bio); | |
1229 | ||
d2a7ad29 | 1230 | return DM_MAPIO_REMAPPED; |
1da177e4 LT |
1231 | } |
1232 | ||
4e4cbee9 CH |
1233 | static int mirror_end_io(struct dm_target *ti, struct bio *bio, |
1234 | blk_status_t *error) | |
1da177e4 | 1235 | { |
70246286 | 1236 | int rw = bio_data_dir(bio); |
1da177e4 | 1237 | struct mirror_set *ms = (struct mirror_set *) ti->private; |
06386bbf JB |
1238 | struct mirror *m = NULL; |
1239 | struct dm_bio_details *bd = NULL; | |
0045d61b MP |
1240 | struct dm_raid1_bio_record *bio_record = |
1241 | dm_per_bio_data(bio, sizeof(struct dm_raid1_bio_record)); | |
1da177e4 LT |
1242 | |
1243 | /* | |
1244 | * We need to dec pending if this was a write. | |
1245 | */ | |
06386bbf | 1246 | if (rw == WRITE) { |
1eff9d32 | 1247 | if (!(bio->bi_opf & REQ_PREFLUSH) && |
28a8f0d3 | 1248 | bio_op(bio) != REQ_OP_DISCARD) |
0045d61b | 1249 | dm_rh_dec(ms->rh, bio_record->write_region); |
1be56909 | 1250 | return DM_ENDIO_DONE; |
06386bbf | 1251 | } |
1da177e4 | 1252 | |
4e4cbee9 | 1253 | if (*error == BLK_STS_NOTSUPP) |
cd15fb64 | 1254 | goto out; |
06386bbf | 1255 | |
9966afaf | 1256 | if (bio->bi_opf & REQ_RAHEAD) |
cd15fb64 | 1257 | goto out; |
06386bbf | 1258 | |
1be56909 | 1259 | if (unlikely(*error)) { |
74d46992 | 1260 | if (!bio_record->details.bi_disk) { |
cd15fb64 MS |
1261 | /* |
1262 | * There wasn't enough memory to record necessary | |
1263 | * information for a retry or there was no other | |
1264 | * mirror in-sync. | |
1265 | */ | |
1266 | DMERR_LIMIT("Mirror read failed."); | |
c6b1e36c | 1267 | return DM_ENDIO_DONE; |
cd15fb64 MS |
1268 | } |
1269 | ||
89c7cd89 | 1270 | m = bio_record->m; |
e03f1a84 | 1271 | |
06386bbf JB |
1272 | DMERR("Mirror read failed from %s. Trying alternative device.", |
1273 | m->dev->name); | |
1274 | ||
06386bbf JB |
1275 | fail_mirror(m, DM_RAID1_READ_ERROR); |
1276 | ||
1277 | /* | |
1278 | * A failed read is requeued for another attempt using an intact | |
1279 | * mirror. | |
1280 | */ | |
1281 | if (default_ok(m) || mirror_available(ms, bio)) { | |
89c7cd89 | 1282 | bd = &bio_record->details; |
06386bbf JB |
1283 | |
1284 | dm_bio_restore(bd, bio); | |
74d46992 | 1285 | bio_record->details.bi_disk = NULL; |
4e4cbee9 | 1286 | bio->bi_status = 0; |
f3a44fe0 | 1287 | |
06386bbf | 1288 | queue_bio(ms, bio, rw); |
19cbbc60 | 1289 | return DM_ENDIO_INCOMPLETE; |
06386bbf JB |
1290 | } |
1291 | DMERR("All replicated volumes dead, failing I/O"); | |
1292 | } | |
1293 | ||
cd15fb64 | 1294 | out: |
74d46992 | 1295 | bio_record->details.bi_disk = NULL; |
cd15fb64 | 1296 | |
1be56909 | 1297 | return DM_ENDIO_DONE; |
1da177e4 LT |
1298 | } |
1299 | ||
b80aa7a0 | 1300 | static void mirror_presuspend(struct dm_target *ti) |
1da177e4 LT |
1301 | { |
1302 | struct mirror_set *ms = (struct mirror_set *) ti->private; | |
1f965b19 | 1303 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
1da177e4 | 1304 | |
04788507 MP |
1305 | struct bio_list holds; |
1306 | struct bio *bio; | |
1307 | ||
b80aa7a0 JB |
1308 | atomic_set(&ms->suspend, 1); |
1309 | ||
f0703040 TY |
1310 | /* |
1311 | * Process bios in the hold list to start recovery waiting | |
1312 | * for bios in the hold list. After the process, no bio has | |
1313 | * a chance to be added in the hold list because ms->suspend | |
1314 | * is set. | |
1315 | */ | |
1316 | spin_lock_irq(&ms->lock); | |
1317 | holds = ms->holds; | |
1318 | bio_list_init(&ms->holds); | |
1319 | spin_unlock_irq(&ms->lock); | |
1320 | ||
1321 | while ((bio = bio_list_pop(&holds))) | |
1322 | hold_bio(ms, bio); | |
1323 | ||
b80aa7a0 JB |
1324 | /* |
1325 | * We must finish up all the work that we've | |
1326 | * generated (i.e. recovery work). | |
1327 | */ | |
1f965b19 | 1328 | dm_rh_stop_recovery(ms->rh); |
33184048 | 1329 | |
33184048 | 1330 | wait_event(_kmirrord_recovery_stopped, |
1f965b19 | 1331 | !dm_rh_recovery_in_flight(ms->rh)); |
33184048 | 1332 | |
b80aa7a0 JB |
1333 | if (log->type->presuspend && log->type->presuspend(log)) |
1334 | /* FIXME: need better error handling */ | |
1335 | DMWARN("log presuspend failed"); | |
1336 | ||
1337 | /* | |
1338 | * Now that recovery is complete/stopped and the | |
1339 | * delayed bios are queued, we need to wait for | |
1340 | * the worker thread to complete. This way, | |
1341 | * we know that all of our I/O has been pushed. | |
1342 | */ | |
1343 | flush_workqueue(ms->kmirrord_wq); | |
1344 | } | |
1345 | ||
1346 | static void mirror_postsuspend(struct dm_target *ti) | |
1347 | { | |
1348 | struct mirror_set *ms = ti->private; | |
1f965b19 | 1349 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
b80aa7a0 | 1350 | |
6b3df0d7 | 1351 | if (log->type->postsuspend && log->type->postsuspend(log)) |
1da177e4 | 1352 | /* FIXME: need better error handling */ |
b80aa7a0 | 1353 | DMWARN("log postsuspend failed"); |
1da177e4 LT |
1354 | } |
1355 | ||
1356 | static void mirror_resume(struct dm_target *ti) | |
1357 | { | |
b80aa7a0 | 1358 | struct mirror_set *ms = ti->private; |
1f965b19 | 1359 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
b80aa7a0 JB |
1360 | |
1361 | atomic_set(&ms->suspend, 0); | |
1da177e4 LT |
1362 | if (log->type->resume && log->type->resume(log)) |
1363 | /* FIXME: need better error handling */ | |
1364 | DMWARN("log resume failed"); | |
1f965b19 | 1365 | dm_rh_start_recovery(ms->rh); |
1da177e4 LT |
1366 | } |
1367 | ||
af195ac8 JB |
1368 | /* |
1369 | * device_status_char | |
1370 | * @m: mirror device/leg we want the status of | |
1371 | * | |
1372 | * We return one character representing the most severe error | |
1373 | * we have encountered. | |
1374 | * A => Alive - No failures | |
1375 | * D => Dead - A write failure occurred leaving mirror out-of-sync | |
1376 | * S => Sync - A sychronization failure occurred, mirror out-of-sync | |
1377 | * R => Read - A read failure occurred, mirror data unaffected | |
1378 | * | |
1379 | * Returns: <char> | |
1380 | */ | |
1381 | static char device_status_char(struct mirror *m) | |
1382 | { | |
1383 | if (!atomic_read(&(m->error_count))) | |
1384 | return 'A'; | |
1385 | ||
64b30c46 MP |
1386 | return (test_bit(DM_RAID1_FLUSH_ERROR, &(m->error_type))) ? 'F' : |
1387 | (test_bit(DM_RAID1_WRITE_ERROR, &(m->error_type))) ? 'D' : | |
af195ac8 JB |
1388 | (test_bit(DM_RAID1_SYNC_ERROR, &(m->error_type))) ? 'S' : |
1389 | (test_bit(DM_RAID1_READ_ERROR, &(m->error_type))) ? 'R' : 'U'; | |
1390 | } | |
1391 | ||
1392 | ||
fd7c092e MP |
1393 | static void mirror_status(struct dm_target *ti, status_type_t type, |
1394 | unsigned status_flags, char *result, unsigned maxlen) | |
1da177e4 | 1395 | { |
315dcc22 | 1396 | unsigned int m, sz = 0; |
ed63287d | 1397 | int num_feature_args = 0; |
1da177e4 | 1398 | struct mirror_set *ms = (struct mirror_set *) ti->private; |
1f965b19 | 1399 | struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh); |
65972a6f | 1400 | char buffer[MAX_NR_MIRRORS + 1]; |
1da177e4 | 1401 | |
1da177e4 LT |
1402 | switch (type) { |
1403 | case STATUSTYPE_INFO: | |
1404 | DMEMIT("%d ", ms->nr_mirrors); | |
af195ac8 | 1405 | for (m = 0; m < ms->nr_mirrors; m++) { |
1da177e4 | 1406 | DMEMIT("%s ", ms->mirror[m].dev->name); |
af195ac8 JB |
1407 | buffer[m] = device_status_char(&(ms->mirror[m])); |
1408 | } | |
1409 | buffer[m] = '\0'; | |
1da177e4 | 1410 | |
af195ac8 | 1411 | DMEMIT("%llu/%llu 1 %s ", |
1f965b19 | 1412 | (unsigned long long)log->type->get_sync_count(log), |
af195ac8 | 1413 | (unsigned long long)ms->nr_regions, buffer); |
315dcc22 | 1414 | |
1f965b19 | 1415 | sz += log->type->status(log, type, result+sz, maxlen-sz); |
315dcc22 | 1416 | |
1da177e4 LT |
1417 | break; |
1418 | ||
1419 | case STATUSTYPE_TABLE: | |
1f965b19 | 1420 | sz = log->type->status(log, type, result, maxlen); |
315dcc22 | 1421 | |
e52b8f6d | 1422 | DMEMIT("%d", ms->nr_mirrors); |
1da177e4 | 1423 | for (m = 0; m < ms->nr_mirrors; m++) |
e52b8f6d | 1424 | DMEMIT(" %s %llu", ms->mirror[m].dev->name, |
b80aa7a0 | 1425 | (unsigned long long)ms->mirror[m].offset); |
a8e6afa2 | 1426 | |
ed63287d LZ |
1427 | num_feature_args += !!errors_handled(ms); |
1428 | num_feature_args += !!keep_log(ms); | |
1429 | if (num_feature_args) { | |
1430 | DMEMIT(" %d", num_feature_args); | |
1431 | if (errors_handled(ms)) | |
1432 | DMEMIT(" handle_errors"); | |
1433 | if (keep_log(ms)) | |
1434 | DMEMIT(" keep_log"); | |
1435 | } | |
1436 | ||
1437 | break; | |
1da177e4 | 1438 | } |
1da177e4 LT |
1439 | } |
1440 | ||
af4874e0 MS |
1441 | static int mirror_iterate_devices(struct dm_target *ti, |
1442 | iterate_devices_callout_fn fn, void *data) | |
1443 | { | |
1444 | struct mirror_set *ms = ti->private; | |
1445 | int ret = 0; | |
1446 | unsigned i; | |
1447 | ||
1448 | for (i = 0; !ret && i < ms->nr_mirrors; i++) | |
1449 | ret = fn(ti, ms->mirror[i].dev, | |
5dea271b | 1450 | ms->mirror[i].offset, ti->len, data); |
af4874e0 MS |
1451 | |
1452 | return ret; | |
1453 | } | |
1454 | ||
1da177e4 LT |
1455 | static struct target_type mirror_target = { |
1456 | .name = "mirror", | |
ed63287d | 1457 | .version = {1, 14, 0}, |
1da177e4 LT |
1458 | .module = THIS_MODULE, |
1459 | .ctr = mirror_ctr, | |
1460 | .dtr = mirror_dtr, | |
1461 | .map = mirror_map, | |
1462 | .end_io = mirror_end_io, | |
b80aa7a0 | 1463 | .presuspend = mirror_presuspend, |
1da177e4 LT |
1464 | .postsuspend = mirror_postsuspend, |
1465 | .resume = mirror_resume, | |
1466 | .status = mirror_status, | |
af4874e0 | 1467 | .iterate_devices = mirror_iterate_devices, |
1da177e4 LT |
1468 | }; |
1469 | ||
1470 | static int __init dm_mirror_init(void) | |
1471 | { | |
1472 | int r; | |
1473 | ||
1da177e4 | 1474 | r = dm_register_target(&mirror_target); |
95f8fac8 | 1475 | if (r < 0) { |
0cd33124 | 1476 | DMERR("Failed to register mirror target"); |
95f8fac8 MP |
1477 | goto bad_target; |
1478 | } | |
1479 | ||
1480 | return 0; | |
1da177e4 | 1481 | |
95f8fac8 | 1482 | bad_target: |
1da177e4 LT |
1483 | return r; |
1484 | } | |
1485 | ||
1486 | static void __exit dm_mirror_exit(void) | |
1487 | { | |
10d3bd09 | 1488 | dm_unregister_target(&mirror_target); |
1da177e4 LT |
1489 | } |
1490 | ||
1491 | /* Module hooks */ | |
1492 | module_init(dm_mirror_init); | |
1493 | module_exit(dm_mirror_exit); | |
1494 | ||
1495 | MODULE_DESCRIPTION(DM_NAME " mirror target"); | |
1496 | MODULE_AUTHOR("Joe Thornber"); | |
1497 | MODULE_LICENSE("GPL"); |