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1 | /* |
2 | * raid1.c : Multiple Devices driver for Linux |
3 | * |
4 | * Copyright (C) 1999, 2000, 2001 Ingo Molnar, Red Hat |
5 | * |
6 | * Copyright (C) 1996, 1997, 1998 Ingo Molnar, Miguel de Icaza, Gadi Oxman |
7 | * |
8 | * RAID-1 management functions. |
9 | * |
10 | * Better read-balancing code written by Mika Kuoppala <miku@iki.fi>, 2000 |
11 | * |
12 | * Fixes to reconstruction by Jakob Østergaard" <jakob@ostenfeld.dk> |
13 | * Various fixes by Neil Brown <neilb@cse.unsw.edu.au> |
14 | * |
15 | * Changes by Peter T. Breuer <ptb@it.uc3m.es> 31/1/2003 to support |
16 | * bitmapped intelligence in resync: |
17 | * |
18 | * - bitmap marked during normal i/o |
19 | * - bitmap used to skip nondirty blocks during sync |
20 | * |
21 | * Additions to bitmap code, (C) 2003-2004 Paul Clements, SteelEye Technology: |
22 | * - persistent bitmap code |
23 | * |
24 | * This program is free software; you can redistribute it and/or modify |
25 | * it under the terms of the GNU General Public License as published by |
26 | * the Free Software Foundation; either version 2, or (at your option) |
27 | * any later version. |
28 | * |
29 | * You should have received a copy of the GNU General Public License |
30 | * (for example /usr/src/linux/COPYING); if not, write to the Free |
31 | * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
32 | */ |
33 | |
34 | #include <linux/slab.h> |
35 | #include <linux/delay.h> |
36 | #include <linux/blkdev.h> |
37 | #include <linux/module.h> |
38 | #include <linux/seq_file.h> |
39 | #include <linux/ratelimit.h> |
40 | #include "md.h" |
41 | #include "raid1.h" |
42 | #include "bitmap.h" |
43 | |
44 | /* |
45 | * Number of guaranteed r1bios in case of extreme VM load: |
46 | */ |
47 | #define NR_RAID1_BIOS 256 |
48 | |
49 | /* when we get a read error on a read-only array, we redirect to another |
50 | * device without failing the first device, or trying to over-write to |
51 | * correct the read error. To keep track of bad blocks on a per-bio |
52 | * level, we store IO_BLOCKED in the appropriate 'bios' pointer |
53 | */ |
54 | #define IO_BLOCKED ((struct bio *)1) |
55 | /* When we successfully write to a known bad-block, we need to remove the |
56 | * bad-block marking which must be done from process context. So we record |
57 | * the success by setting devs[n].bio to IO_MADE_GOOD |
58 | */ |
59 | #define IO_MADE_GOOD ((struct bio *)2) |
60 | |
61 | #define BIO_SPECIAL(bio) ((unsigned long)bio <= 2) |
62 | |
63 | /* When there are this many requests queue to be written by |
64 | * the raid1 thread, we become 'congested' to provide back-pressure |
65 | * for writeback. |
66 | */ |
67 | static int max_queued_requests = 1024; |
68 | |
69 | static void allow_barrier(struct r1conf *conf); |
70 | static void lower_barrier(struct r1conf *conf); |
71 | |
72 | static void * r1bio_pool_alloc(gfp_t gfp_flags, void *data) |
73 | { |
74 | struct pool_info *pi = data; |
75 | int size = offsetof(struct r1bio, bios[pi->raid_disks]); |
76 | |
77 | /* allocate a r1bio with room for raid_disks entries in the bios array */ |
78 | return kzalloc(size, gfp_flags); |
79 | } |
80 | |
81 | static void r1bio_pool_free(void *r1_bio, void *data) |
82 | { |
83 | kfree(r1_bio); |
84 | } |
85 | |
86 | #define RESYNC_BLOCK_SIZE (64*1024) |
87 | //#define RESYNC_BLOCK_SIZE PAGE_SIZE |
88 | #define RESYNC_SECTORS (RESYNC_BLOCK_SIZE >> 9) |
89 | #define RESYNC_PAGES ((RESYNC_BLOCK_SIZE + PAGE_SIZE-1) / PAGE_SIZE) |
90 | #define RESYNC_WINDOW (2048*1024) |
91 | |
92 | static void * r1buf_pool_alloc(gfp_t gfp_flags, void *data) |
93 | { |
94 | struct pool_info *pi = data; |
95 | struct page *page; |
96 | struct r1bio *r1_bio; |
97 | struct bio *bio; |
98 | int i, j; |
99 | |
100 | r1_bio = r1bio_pool_alloc(gfp_flags, pi); |
101 | if (!r1_bio) |
102 | return NULL; |
103 | |
104 | /* |
105 | * Allocate bios : 1 for reading, n-1 for writing |
106 | */ |
107 | for (j = pi->raid_disks ; j-- ; ) { |
108 | bio = bio_kmalloc(gfp_flags, RESYNC_PAGES); |
109 | if (!bio) |
110 | goto out_free_bio; |
111 | r1_bio->bios[j] = bio; |
112 | } |
113 | /* |
114 | * Allocate RESYNC_PAGES data pages and attach them to |
115 | * the first bio. |
116 | * If this is a user-requested check/repair, allocate |
117 | * RESYNC_PAGES for each bio. |
118 | */ |
119 | if (test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery)) |
120 | j = pi->raid_disks; |
121 | else |
122 | j = 1; |
123 | while(j--) { |
124 | bio = r1_bio->bios[j]; |
125 | for (i = 0; i < RESYNC_PAGES; i++) { |
126 | page = alloc_page(gfp_flags); |
127 | if (unlikely(!page)) |
128 | goto out_free_pages; |
129 | |
130 | bio->bi_io_vec[i].bv_page = page; |
131 | bio->bi_vcnt = i+1; |
132 | } |
133 | } |
134 | /* If not user-requests, copy the page pointers to all bios */ |
135 | if (!test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery)) { |
136 | for (i=0; i<RESYNC_PAGES ; i++) |
137 | for (j=1; j<pi->raid_disks; j++) |
138 | r1_bio->bios[j]->bi_io_vec[i].bv_page = |
139 | r1_bio->bios[0]->bi_io_vec[i].bv_page; |
140 | } |
141 | |
142 | r1_bio->master_bio = NULL; |
143 | |
144 | return r1_bio; |
145 | |
146 | out_free_pages: |
147 | for (j=0 ; j < pi->raid_disks; j++) |
148 | for (i=0; i < r1_bio->bios[j]->bi_vcnt ; i++) |
149 | put_page(r1_bio->bios[j]->bi_io_vec[i].bv_page); |
150 | j = -1; |
151 | out_free_bio: |
152 | while (++j < pi->raid_disks) |
153 | bio_put(r1_bio->bios[j]); |
154 | r1bio_pool_free(r1_bio, data); |
155 | return NULL; |
156 | } |
157 | |
158 | static void r1buf_pool_free(void *__r1_bio, void *data) |
159 | { |
160 | struct pool_info *pi = data; |
161 | int i,j; |
162 | struct r1bio *r1bio = __r1_bio; |
163 | |
164 | for (i = 0; i < RESYNC_PAGES; i++) |
165 | for (j = pi->raid_disks; j-- ;) { |
166 | if (j == 0 || |
167 | r1bio->bios[j]->bi_io_vec[i].bv_page != |
168 | r1bio->bios[0]->bi_io_vec[i].bv_page) |
169 | safe_put_page(r1bio->bios[j]->bi_io_vec[i].bv_page); |
170 | } |
171 | for (i=0 ; i < pi->raid_disks; i++) |
172 | bio_put(r1bio->bios[i]); |
173 | |
174 | r1bio_pool_free(r1bio, data); |
175 | } |
176 | |
177 | static void put_all_bios(struct r1conf *conf, struct r1bio *r1_bio) |
178 | { |
179 | int i; |
180 | |
181 | for (i = 0; i < conf->raid_disks * 2; i++) { |
182 | struct bio **bio = r1_bio->bios + i; |
183 | if (!BIO_SPECIAL(*bio)) |
184 | bio_put(*bio); |
185 | *bio = NULL; |
186 | } |
187 | } |
188 | |
189 | static void free_r1bio(struct r1bio *r1_bio) |
190 | { |
191 | struct r1conf *conf = r1_bio->mddev->private; |
192 | |
193 | put_all_bios(conf, r1_bio); |
194 | mempool_free(r1_bio, conf->r1bio_pool); |
195 | } |
196 | |
197 | static void put_buf(struct r1bio *r1_bio) |
198 | { |
199 | struct r1conf *conf = r1_bio->mddev->private; |
200 | int i; |
201 | |
202 | for (i = 0; i < conf->raid_disks * 2; i++) { |
203 | struct bio *bio = r1_bio->bios[i]; |
204 | if (bio->bi_end_io) |
205 | rdev_dec_pending(conf->mirrors[i].rdev, r1_bio->mddev); |
206 | } |
207 | |
208 | mempool_free(r1_bio, conf->r1buf_pool); |
209 | |
210 | lower_barrier(conf); |
211 | } |
212 | |
213 | static void reschedule_retry(struct r1bio *r1_bio) |
214 | { |
215 | unsigned long flags; |
216 | struct mddev *mddev = r1_bio->mddev; |
217 | struct r1conf *conf = mddev->private; |
218 | |
219 | spin_lock_irqsave(&conf->device_lock, flags); |
220 | list_add(&r1_bio->retry_list, &conf->retry_list); |
221 | conf->nr_queued ++; |
222 | spin_unlock_irqrestore(&conf->device_lock, flags); |
223 | |
224 | wake_up(&conf->wait_barrier); |
225 | md_wakeup_thread(mddev->thread); |
226 | } |
227 | |
228 | /* |
229 | * raid_end_bio_io() is called when we have finished servicing a mirrored |
230 | * operation and are ready to return a success/failure code to the buffer |
231 | * cache layer. |
232 | */ |
233 | static void call_bio_endio(struct r1bio *r1_bio) |
234 | { |
235 | struct bio *bio = r1_bio->master_bio; |
236 | int done; |
237 | struct r1conf *conf = r1_bio->mddev->private; |
238 | |
239 | if (bio->bi_phys_segments) { |
240 | unsigned long flags; |
241 | spin_lock_irqsave(&conf->device_lock, flags); |
242 | bio->bi_phys_segments--; |
243 | done = (bio->bi_phys_segments == 0); |
244 | spin_unlock_irqrestore(&conf->device_lock, flags); |
245 | } else |
246 | done = 1; |
247 | |
248 | if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) |
249 | clear_bit(BIO_UPTODATE, &bio->bi_flags); |
250 | if (done) { |
251 | bio_endio(bio, 0); |
252 | /* |
253 | * Wake up any possible resync thread that waits for the device |
254 | * to go idle. |
255 | */ |
256 | allow_barrier(conf); |
257 | } |
258 | } |
259 | |
260 | static void raid_end_bio_io(struct r1bio *r1_bio) |
261 | { |
262 | struct bio *bio = r1_bio->master_bio; |
263 | |
264 | /* if nobody has done the final endio yet, do it now */ |
265 | if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) { |
266 | pr_debug("raid1: sync end %s on sectors %llu-%llu\n", |
267 | (bio_data_dir(bio) == WRITE) ? "write" : "read", |
268 | (unsigned long long) bio->bi_sector, |
269 | (unsigned long long) bio->bi_sector + |
270 | (bio->bi_size >> 9) - 1); |
271 | |
272 | call_bio_endio(r1_bio); |
273 | } |
274 | free_r1bio(r1_bio); |
275 | } |
276 | |
277 | /* |
278 | * Update disk head position estimator based on IRQ completion info. |
279 | */ |
280 | static inline void update_head_pos(int disk, struct r1bio *r1_bio) |
281 | { |
282 | struct r1conf *conf = r1_bio->mddev->private; |
283 | |
284 | conf->mirrors[disk].head_position = |
285 | r1_bio->sector + (r1_bio->sectors); |
286 | } |
287 | |
288 | /* |
289 | * Find the disk number which triggered given bio |
290 | */ |
291 | static int find_bio_disk(struct r1bio *r1_bio, struct bio *bio) |
292 | { |
293 | int mirror; |
294 | struct r1conf *conf = r1_bio->mddev->private; |
295 | int raid_disks = conf->raid_disks; |
296 | |
297 | for (mirror = 0; mirror < raid_disks * 2; mirror++) |
298 | if (r1_bio->bios[mirror] == bio) |
299 | break; |
300 | |
301 | BUG_ON(mirror == raid_disks * 2); |
302 | update_head_pos(mirror, r1_bio); |
303 | |
304 | return mirror; |
305 | } |
306 | |
307 | static void raid1_end_read_request(struct bio *bio, int error) |
308 | { |
309 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); |
310 | struct r1bio *r1_bio = bio->bi_private; |
311 | int mirror; |
312 | struct r1conf *conf = r1_bio->mddev->private; |
313 | |
314 | mirror = r1_bio->read_disk; |
315 | /* |
316 | * this branch is our 'one mirror IO has finished' event handler: |
317 | */ |
318 | update_head_pos(mirror, r1_bio); |
319 | |
320 | if (uptodate) |
321 | set_bit(R1BIO_Uptodate, &r1_bio->state); |
322 | else { |
323 | /* If all other devices have failed, we want to return |
324 | * the error upwards rather than fail the last device. |
325 | * Here we redefine "uptodate" to mean "Don't want to retry" |
326 | */ |
327 | unsigned long flags; |
328 | spin_lock_irqsave(&conf->device_lock, flags); |
329 | if (r1_bio->mddev->degraded == conf->raid_disks || |
330 | (r1_bio->mddev->degraded == conf->raid_disks-1 && |
331 | !test_bit(Faulty, &conf->mirrors[mirror].rdev->flags))) |
332 | uptodate = 1; |
333 | spin_unlock_irqrestore(&conf->device_lock, flags); |
334 | } |
335 | |
336 | if (uptodate) { |
337 | raid_end_bio_io(r1_bio); |
338 | rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev); |
339 | } else { |
340 | /* |
341 | * oops, read error: |
342 | */ |
343 | char b[BDEVNAME_SIZE]; |
344 | printk_ratelimited( |
345 | KERN_ERR "md/raid1:%s: %s: " |
346 | "rescheduling sector %llu\n", |
347 | mdname(conf->mddev), |
348 | bdevname(conf->mirrors[mirror].rdev->bdev, |
349 | b), |
350 | (unsigned long long)r1_bio->sector); |
351 | set_bit(R1BIO_ReadError, &r1_bio->state); |
352 | reschedule_retry(r1_bio); |
353 | /* don't drop the reference on read_disk yet */ |
354 | } |
355 | } |
356 | |
357 | static void close_write(struct r1bio *r1_bio) |
358 | { |
359 | /* it really is the end of this request */ |
360 | if (test_bit(R1BIO_BehindIO, &r1_bio->state)) { |
361 | /* free extra copy of the data pages */ |
362 | int i = r1_bio->behind_page_count; |
363 | while (i--) |
364 | safe_put_page(r1_bio->behind_bvecs[i].bv_page); |
365 | kfree(r1_bio->behind_bvecs); |
366 | r1_bio->behind_bvecs = NULL; |
367 | } |
368 | /* clear the bitmap if all writes complete successfully */ |
369 | bitmap_endwrite(r1_bio->mddev->bitmap, r1_bio->sector, |
370 | r1_bio->sectors, |
371 | !test_bit(R1BIO_Degraded, &r1_bio->state), |
372 | test_bit(R1BIO_BehindIO, &r1_bio->state)); |
373 | md_write_end(r1_bio->mddev); |
374 | } |
375 | |
376 | static void r1_bio_write_done(struct r1bio *r1_bio) |
377 | { |
378 | if (!atomic_dec_and_test(&r1_bio->remaining)) |
379 | return; |
380 | |
381 | if (test_bit(R1BIO_WriteError, &r1_bio->state)) |
382 | reschedule_retry(r1_bio); |
383 | else { |
384 | close_write(r1_bio); |
385 | if (test_bit(R1BIO_MadeGood, &r1_bio->state)) |
386 | reschedule_retry(r1_bio); |
387 | else |
388 | raid_end_bio_io(r1_bio); |
389 | } |
390 | } |
391 | |
392 | static void raid1_end_write_request(struct bio *bio, int error) |
393 | { |
394 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); |
395 | struct r1bio *r1_bio = bio->bi_private; |
396 | int mirror, behind = test_bit(R1BIO_BehindIO, &r1_bio->state); |
397 | struct r1conf *conf = r1_bio->mddev->private; |
398 | struct bio *to_put = NULL; |
399 | |
400 | mirror = find_bio_disk(r1_bio, bio); |
401 | |
402 | /* |
403 | * 'one mirror IO has finished' event handler: |
404 | */ |
405 | if (!uptodate) { |
406 | set_bit(WriteErrorSeen, |
407 | &conf->mirrors[mirror].rdev->flags); |
408 | if (!test_and_set_bit(WantReplacement, |
409 | &conf->mirrors[mirror].rdev->flags)) |
410 | set_bit(MD_RECOVERY_NEEDED, & |
411 | conf->mddev->recovery); |
412 | |
413 | set_bit(R1BIO_WriteError, &r1_bio->state); |
414 | } else { |
415 | /* |
416 | * Set R1BIO_Uptodate in our master bio, so that we |
417 | * will return a good error code for to the higher |
418 | * levels even if IO on some other mirrored buffer |
419 | * fails. |
420 | * |
421 | * The 'master' represents the composite IO operation |
422 | * to user-side. So if something waits for IO, then it |
423 | * will wait for the 'master' bio. |
424 | */ |
425 | sector_t first_bad; |
426 | int bad_sectors; |
427 | |
428 | r1_bio->bios[mirror] = NULL; |
429 | to_put = bio; |
430 | set_bit(R1BIO_Uptodate, &r1_bio->state); |
431 | |
432 | /* Maybe we can clear some bad blocks. */ |
433 | if (is_badblock(conf->mirrors[mirror].rdev, |
434 | r1_bio->sector, r1_bio->sectors, |
435 | &first_bad, &bad_sectors)) { |
436 | r1_bio->bios[mirror] = IO_MADE_GOOD; |
437 | set_bit(R1BIO_MadeGood, &r1_bio->state); |
438 | } |
439 | } |
440 | |
441 | if (behind) { |
442 | if (test_bit(WriteMostly, &conf->mirrors[mirror].rdev->flags)) |
443 | atomic_dec(&r1_bio->behind_remaining); |
444 | |
445 | /* |
446 | * In behind mode, we ACK the master bio once the I/O |
447 | * has safely reached all non-writemostly |
448 | * disks. Setting the Returned bit ensures that this |
449 | * gets done only once -- we don't ever want to return |
450 | * -EIO here, instead we'll wait |
451 | */ |
452 | if (atomic_read(&r1_bio->behind_remaining) >= (atomic_read(&r1_bio->remaining)-1) && |
453 | test_bit(R1BIO_Uptodate, &r1_bio->state)) { |
454 | /* Maybe we can return now */ |
455 | if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) { |
456 | struct bio *mbio = r1_bio->master_bio; |
457 | pr_debug("raid1: behind end write sectors" |
458 | " %llu-%llu\n", |
459 | (unsigned long long) mbio->bi_sector, |
460 | (unsigned long long) mbio->bi_sector + |
461 | (mbio->bi_size >> 9) - 1); |
462 | call_bio_endio(r1_bio); |
463 | } |
464 | } |
465 | } |
466 | if (r1_bio->bios[mirror] == NULL) |
467 | rdev_dec_pending(conf->mirrors[mirror].rdev, |
468 | conf->mddev); |
469 | |
470 | /* |
471 | * Let's see if all mirrored write operations have finished |
472 | * already. |
473 | */ |
474 | r1_bio_write_done(r1_bio); |
475 | |
476 | if (to_put) |
477 | bio_put(to_put); |
478 | } |
479 | |
480 | |
481 | /* |
482 | * This routine returns the disk from which the requested read should |
483 | * be done. There is a per-array 'next expected sequential IO' sector |
484 | * number - if this matches on the next IO then we use the last disk. |
485 | * There is also a per-disk 'last know head position' sector that is |
486 | * maintained from IRQ contexts, both the normal and the resync IO |
487 | * completion handlers update this position correctly. If there is no |
488 | * perfect sequential match then we pick the disk whose head is closest. |
489 | * |
490 | * If there are 2 mirrors in the same 2 devices, performance degrades |
491 | * because position is mirror, not device based. |
492 | * |
493 | * The rdev for the device selected will have nr_pending incremented. |
494 | */ |
495 | static int read_balance(struct r1conf *conf, struct r1bio *r1_bio, int *max_sectors) |
496 | { |
497 | const sector_t this_sector = r1_bio->sector; |
498 | int sectors; |
499 | int best_good_sectors; |
500 | int best_disk, best_dist_disk, best_pending_disk; |
501 | int has_nonrot_disk; |
502 | int disk; |
503 | sector_t best_dist; |
504 | unsigned int min_pending; |
505 | struct md_rdev *rdev; |
506 | int choose_first; |
507 | int choose_next_idle; |
508 | |
509 | rcu_read_lock(); |
510 | /* |
511 | * Check if we can balance. We can balance on the whole |
512 | * device if no resync is going on, or below the resync window. |
513 | * We take the first readable disk when above the resync window. |
514 | */ |
515 | retry: |
516 | sectors = r1_bio->sectors; |
517 | best_disk = -1; |
518 | best_dist_disk = -1; |
519 | best_dist = MaxSector; |
520 | best_pending_disk = -1; |
521 | min_pending = UINT_MAX; |
522 | best_good_sectors = 0; |
523 | has_nonrot_disk = 0; |
524 | choose_next_idle = 0; |
525 | |
526 | if (conf->mddev->recovery_cp < MaxSector && |
527 | (this_sector + sectors >= conf->next_resync)) |
528 | choose_first = 1; |
529 | else |
530 | choose_first = 0; |
531 | |
532 | for (disk = 0 ; disk < conf->raid_disks * 2 ; disk++) { |
533 | sector_t dist; |
534 | sector_t first_bad; |
535 | int bad_sectors; |
536 | unsigned int pending; |
537 | bool nonrot; |
538 | |
539 | rdev = rcu_dereference(conf->mirrors[disk].rdev); |
540 | if (r1_bio->bios[disk] == IO_BLOCKED |
541 | || rdev == NULL |
542 | || test_bit(Unmerged, &rdev->flags) |
543 | || test_bit(Faulty, &rdev->flags)) |
544 | continue; |
545 | if (!test_bit(In_sync, &rdev->flags) && |
546 | rdev->recovery_offset < this_sector + sectors) |
547 | continue; |
548 | if (test_bit(WriteMostly, &rdev->flags)) { |
549 | /* Don't balance among write-mostly, just |
550 | * use the first as a last resort */ |
551 | if (best_disk < 0) { |
552 | if (is_badblock(rdev, this_sector, sectors, |
553 | &first_bad, &bad_sectors)) { |
554 | if (first_bad < this_sector) |
555 | /* Cannot use this */ |
556 | continue; |
557 | best_good_sectors = first_bad - this_sector; |
558 | } else |
559 | best_good_sectors = sectors; |
560 | best_disk = disk; |
561 | } |
562 | continue; |
563 | } |
564 | /* This is a reasonable device to use. It might |
565 | * even be best. |
566 | */ |
567 | if (is_badblock(rdev, this_sector, sectors, |
568 | &first_bad, &bad_sectors)) { |
569 | if (best_dist < MaxSector) |
570 | /* already have a better device */ |
571 | continue; |
572 | if (first_bad <= this_sector) { |
573 | /* cannot read here. If this is the 'primary' |
574 | * device, then we must not read beyond |
575 | * bad_sectors from another device.. |
576 | */ |
577 | bad_sectors -= (this_sector - first_bad); |
578 | if (choose_first && sectors > bad_sectors) |
579 | sectors = bad_sectors; |
580 | if (best_good_sectors > sectors) |
581 | best_good_sectors = sectors; |
582 | |
583 | } else { |
584 | sector_t good_sectors = first_bad - this_sector; |
585 | if (good_sectors > best_good_sectors) { |
586 | best_good_sectors = good_sectors; |
587 | best_disk = disk; |
588 | } |
589 | if (choose_first) |
590 | break; |
591 | } |
592 | continue; |
593 | } else |
594 | best_good_sectors = sectors; |
595 | |
596 | nonrot = blk_queue_nonrot(bdev_get_queue(rdev->bdev)); |
597 | has_nonrot_disk |= nonrot; |
598 | pending = atomic_read(&rdev->nr_pending); |
599 | dist = abs(this_sector - conf->mirrors[disk].head_position); |
600 | if (choose_first) { |
601 | best_disk = disk; |
602 | break; |
603 | } |
604 | /* Don't change to another disk for sequential reads */ |
605 | if (conf->mirrors[disk].next_seq_sect == this_sector |
606 | || dist == 0) { |
607 | int opt_iosize = bdev_io_opt(rdev->bdev) >> 9; |
608 | struct raid1_info *mirror = &conf->mirrors[disk]; |
609 | |
610 | best_disk = disk; |
611 | /* |
612 | * If buffered sequential IO size exceeds optimal |
613 | * iosize, check if there is idle disk. If yes, choose |
614 | * the idle disk. read_balance could already choose an |
615 | * idle disk before noticing it's a sequential IO in |
616 | * this disk. This doesn't matter because this disk |
617 | * will idle, next time it will be utilized after the |
618 | * first disk has IO size exceeds optimal iosize. In |
619 | * this way, iosize of the first disk will be optimal |
620 | * iosize at least. iosize of the second disk might be |
621 | * small, but not a big deal since when the second disk |
622 | * starts IO, the first disk is likely still busy. |
623 | */ |
624 | if (nonrot && opt_iosize > 0 && |
625 | mirror->seq_start != MaxSector && |
626 | mirror->next_seq_sect > opt_iosize && |
627 | mirror->next_seq_sect - opt_iosize >= |
628 | mirror->seq_start) { |
629 | choose_next_idle = 1; |
630 | continue; |
631 | } |
632 | break; |
633 | } |
634 | /* If device is idle, use it */ |
635 | if (pending == 0) { |
636 | best_disk = disk; |
637 | break; |
638 | } |
639 | |
640 | if (choose_next_idle) |
641 | continue; |
642 | |
643 | if (min_pending > pending) { |
644 | min_pending = pending; |
645 | best_pending_disk = disk; |
646 | } |
647 | |
648 | if (dist < best_dist) { |
649 | best_dist = dist; |
650 | best_dist_disk = disk; |
651 | } |
652 | } |
653 | |
654 | /* |
655 | * If all disks are rotational, choose the closest disk. If any disk is |
656 | * non-rotational, choose the disk with less pending request even the |
657 | * disk is rotational, which might/might not be optimal for raids with |
658 | * mixed ratation/non-rotational disks depending on workload. |
659 | */ |
660 | if (best_disk == -1) { |
661 | if (has_nonrot_disk) |
662 | best_disk = best_pending_disk; |
663 | else |
664 | best_disk = best_dist_disk; |
665 | } |
666 | |
667 | if (best_disk >= 0) { |
668 | rdev = rcu_dereference(conf->mirrors[best_disk].rdev); |
669 | if (!rdev) |
670 | goto retry; |
671 | atomic_inc(&rdev->nr_pending); |
672 | if (test_bit(Faulty, &rdev->flags)) { |
673 | /* cannot risk returning a device that failed |
674 | * before we inc'ed nr_pending |
675 | */ |
676 | rdev_dec_pending(rdev, conf->mddev); |
677 | goto retry; |
678 | } |
679 | sectors = best_good_sectors; |
680 | |
681 | if (conf->mirrors[best_disk].next_seq_sect != this_sector) |
682 | conf->mirrors[best_disk].seq_start = this_sector; |
683 | |
684 | conf->mirrors[best_disk].next_seq_sect = this_sector + sectors; |
685 | } |
686 | rcu_read_unlock(); |
687 | *max_sectors = sectors; |
688 | |
689 | return best_disk; |
690 | } |
691 | |
692 | static int raid1_mergeable_bvec(struct request_queue *q, |
693 | struct bvec_merge_data *bvm, |
694 | struct bio_vec *biovec) |
695 | { |
696 | struct mddev *mddev = q->queuedata; |
697 | struct r1conf *conf = mddev->private; |
698 | sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev); |
699 | int max = biovec->bv_len; |
700 | |
701 | if (mddev->merge_check_needed) { |
702 | int disk; |
703 | rcu_read_lock(); |
704 | for (disk = 0; disk < conf->raid_disks * 2; disk++) { |
705 | struct md_rdev *rdev = rcu_dereference( |
706 | conf->mirrors[disk].rdev); |
707 | if (rdev && !test_bit(Faulty, &rdev->flags)) { |
708 | struct request_queue *q = |
709 | bdev_get_queue(rdev->bdev); |
710 | if (q->merge_bvec_fn) { |
711 | bvm->bi_sector = sector + |
712 | rdev->data_offset; |
713 | bvm->bi_bdev = rdev->bdev; |
714 | max = min(max, q->merge_bvec_fn( |
715 | q, bvm, biovec)); |
716 | } |
717 | } |
718 | } |
719 | rcu_read_unlock(); |
720 | } |
721 | return max; |
722 | |
723 | } |
724 | |
725 | int md_raid1_congested(struct mddev *mddev, int bits) |
726 | { |
727 | struct r1conf *conf = mddev->private; |
728 | int i, ret = 0; |
729 | |
730 | if ((bits & (1 << BDI_async_congested)) && |
731 | conf->pending_count >= max_queued_requests) |
732 | return 1; |
733 | |
734 | rcu_read_lock(); |
735 | for (i = 0; i < conf->raid_disks * 2; i++) { |
736 | struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev); |
737 | if (rdev && !test_bit(Faulty, &rdev->flags)) { |
738 | struct request_queue *q = bdev_get_queue(rdev->bdev); |
739 | |
740 | BUG_ON(!q); |
741 | |
742 | /* Note the '|| 1' - when read_balance prefers |
743 | * non-congested targets, it can be removed |
744 | */ |
745 | if ((bits & (1<<BDI_async_congested)) || 1) |
746 | ret |= bdi_congested(&q->backing_dev_info, bits); |
747 | else |
748 | ret &= bdi_congested(&q->backing_dev_info, bits); |
749 | } |
750 | } |
751 | rcu_read_unlock(); |
752 | return ret; |
753 | } |
754 | EXPORT_SYMBOL_GPL(md_raid1_congested); |
755 | |
756 | static int raid1_congested(void *data, int bits) |
757 | { |
758 | struct mddev *mddev = data; |
759 | |
760 | return mddev_congested(mddev, bits) || |
761 | md_raid1_congested(mddev, bits); |
762 | } |
763 | |
764 | static void flush_pending_writes(struct r1conf *conf) |
765 | { |
766 | /* Any writes that have been queued but are awaiting |
767 | * bitmap updates get flushed here. |
768 | */ |
769 | spin_lock_irq(&conf->device_lock); |
770 | |
771 | if (conf->pending_bio_list.head) { |
772 | struct bio *bio; |
773 | bio = bio_list_get(&conf->pending_bio_list); |
774 | conf->pending_count = 0; |
775 | spin_unlock_irq(&conf->device_lock); |
776 | /* flush any pending bitmap writes to |
777 | * disk before proceeding w/ I/O */ |
778 | bitmap_unplug(conf->mddev->bitmap); |
779 | wake_up(&conf->wait_barrier); |
780 | |
781 | while (bio) { /* submit pending writes */ |
782 | struct bio *next = bio->bi_next; |
783 | bio->bi_next = NULL; |
784 | if (unlikely((bio->bi_rw & REQ_DISCARD) && |
785 | !blk_queue_discard(bdev_get_queue(bio->bi_bdev)))) |
786 | /* Just ignore it */ |
787 | bio_endio(bio, 0); |
788 | else |
789 | generic_make_request(bio); |
790 | bio = next; |
791 | } |
792 | } else |
793 | spin_unlock_irq(&conf->device_lock); |
794 | } |
795 | |
796 | /* Barriers.... |
797 | * Sometimes we need to suspend IO while we do something else, |
798 | * either some resync/recovery, or reconfigure the array. |
799 | * To do this we raise a 'barrier'. |
800 | * The 'barrier' is a counter that can be raised multiple times |
801 | * to count how many activities are happening which preclude |
802 | * normal IO. |
803 | * We can only raise the barrier if there is no pending IO. |
804 | * i.e. if nr_pending == 0. |
805 | * We choose only to raise the barrier if no-one is waiting for the |
806 | * barrier to go down. This means that as soon as an IO request |
807 | * is ready, no other operations which require a barrier will start |
808 | * until the IO request has had a chance. |
809 | * |
810 | * So: regular IO calls 'wait_barrier'. When that returns there |
811 | * is no backgroup IO happening, It must arrange to call |
812 | * allow_barrier when it has finished its IO. |
813 | * backgroup IO calls must call raise_barrier. Once that returns |
814 | * there is no normal IO happeing. It must arrange to call |
815 | * lower_barrier when the particular background IO completes. |
816 | */ |
817 | #define RESYNC_DEPTH 32 |
818 | |
819 | static void raise_barrier(struct r1conf *conf) |
820 | { |
821 | spin_lock_irq(&conf->resync_lock); |
822 | |
823 | /* Wait until no block IO is waiting */ |
824 | wait_event_lock_irq(conf->wait_barrier, !conf->nr_waiting, |
825 | conf->resync_lock); |
826 | |
827 | /* block any new IO from starting */ |
828 | conf->barrier++; |
829 | |
830 | /* Now wait for all pending IO to complete */ |
831 | wait_event_lock_irq(conf->wait_barrier, |
832 | !conf->nr_pending && conf->barrier < RESYNC_DEPTH, |
833 | conf->resync_lock); |
834 | |
835 | spin_unlock_irq(&conf->resync_lock); |
836 | } |
837 | |
838 | static void lower_barrier(struct r1conf *conf) |
839 | { |
840 | unsigned long flags; |
841 | BUG_ON(conf->barrier <= 0); |
842 | spin_lock_irqsave(&conf->resync_lock, flags); |
843 | conf->barrier--; |
844 | spin_unlock_irqrestore(&conf->resync_lock, flags); |
845 | wake_up(&conf->wait_barrier); |
846 | } |
847 | |
848 | static void wait_barrier(struct r1conf *conf) |
849 | { |
850 | spin_lock_irq(&conf->resync_lock); |
851 | if (conf->barrier) { |
852 | conf->nr_waiting++; |
853 | /* Wait for the barrier to drop. |
854 | * However if there are already pending |
855 | * requests (preventing the barrier from |
856 | * rising completely), and the |
857 | * pre-process bio queue isn't empty, |
858 | * then don't wait, as we need to empty |
859 | * that queue to get the nr_pending |
860 | * count down. |
861 | */ |
862 | wait_event_lock_irq(conf->wait_barrier, |
863 | !conf->barrier || |
864 | (conf->nr_pending && |
865 | current->bio_list && |
866 | !bio_list_empty(current->bio_list)), |
867 | conf->resync_lock); |
868 | conf->nr_waiting--; |
869 | } |
870 | conf->nr_pending++; |
871 | spin_unlock_irq(&conf->resync_lock); |
872 | } |
873 | |
874 | static void allow_barrier(struct r1conf *conf) |
875 | { |
876 | unsigned long flags; |
877 | spin_lock_irqsave(&conf->resync_lock, flags); |
878 | conf->nr_pending--; |
879 | spin_unlock_irqrestore(&conf->resync_lock, flags); |
880 | wake_up(&conf->wait_barrier); |
881 | } |
882 | |
883 | static void freeze_array(struct r1conf *conf) |
884 | { |
885 | /* stop syncio and normal IO and wait for everything to |
886 | * go quite. |
887 | * We increment barrier and nr_waiting, and then |
888 | * wait until nr_pending match nr_queued+1 |
889 | * This is called in the context of one normal IO request |
890 | * that has failed. Thus any sync request that might be pending |
891 | * will be blocked by nr_pending, and we need to wait for |
892 | * pending IO requests to complete or be queued for re-try. |
893 | * Thus the number queued (nr_queued) plus this request (1) |
894 | * must match the number of pending IOs (nr_pending) before |
895 | * we continue. |
896 | */ |
897 | spin_lock_irq(&conf->resync_lock); |
898 | conf->barrier++; |
899 | conf->nr_waiting++; |
900 | wait_event_lock_irq_cmd(conf->wait_barrier, |
901 | conf->nr_pending == conf->nr_queued+1, |
902 | conf->resync_lock, |
903 | flush_pending_writes(conf)); |
904 | spin_unlock_irq(&conf->resync_lock); |
905 | } |
906 | static void unfreeze_array(struct r1conf *conf) |
907 | { |
908 | /* reverse the effect of the freeze */ |
909 | spin_lock_irq(&conf->resync_lock); |
910 | conf->barrier--; |
911 | conf->nr_waiting--; |
912 | wake_up(&conf->wait_barrier); |
913 | spin_unlock_irq(&conf->resync_lock); |
914 | } |
915 | |
916 | |
917 | /* duplicate the data pages for behind I/O |
918 | */ |
919 | static void alloc_behind_pages(struct bio *bio, struct r1bio *r1_bio) |
920 | { |
921 | int i; |
922 | struct bio_vec *bvec; |
923 | struct bio_vec *bvecs = kzalloc(bio->bi_vcnt * sizeof(struct bio_vec), |
924 | GFP_NOIO); |
925 | if (unlikely(!bvecs)) |
926 | return; |
927 | |
928 | bio_for_each_segment(bvec, bio, i) { |
929 | bvecs[i] = *bvec; |
930 | bvecs[i].bv_page = alloc_page(GFP_NOIO); |
931 | if (unlikely(!bvecs[i].bv_page)) |
932 | goto do_sync_io; |
933 | memcpy(kmap(bvecs[i].bv_page) + bvec->bv_offset, |
934 | kmap(bvec->bv_page) + bvec->bv_offset, bvec->bv_len); |
935 | kunmap(bvecs[i].bv_page); |
936 | kunmap(bvec->bv_page); |
937 | } |
938 | r1_bio->behind_bvecs = bvecs; |
939 | r1_bio->behind_page_count = bio->bi_vcnt; |
940 | set_bit(R1BIO_BehindIO, &r1_bio->state); |
941 | return; |
942 | |
943 | do_sync_io: |
944 | for (i = 0; i < bio->bi_vcnt; i++) |
945 | if (bvecs[i].bv_page) |
946 | put_page(bvecs[i].bv_page); |
947 | kfree(bvecs); |
948 | pr_debug("%dB behind alloc failed, doing sync I/O\n", bio->bi_size); |
949 | } |
950 | |
951 | struct raid1_plug_cb { |
952 | struct blk_plug_cb cb; |
953 | struct bio_list pending; |
954 | int pending_cnt; |
955 | }; |
956 | |
957 | static void raid1_unplug(struct blk_plug_cb *cb, bool from_schedule) |
958 | { |
959 | struct raid1_plug_cb *plug = container_of(cb, struct raid1_plug_cb, |
960 | cb); |
961 | struct mddev *mddev = plug->cb.data; |
962 | struct r1conf *conf = mddev->private; |
963 | struct bio *bio; |
964 | |
965 | if (from_schedule || current->bio_list) { |
966 | spin_lock_irq(&conf->device_lock); |
967 | bio_list_merge(&conf->pending_bio_list, &plug->pending); |
968 | conf->pending_count += plug->pending_cnt; |
969 | spin_unlock_irq(&conf->device_lock); |
970 | wake_up(&conf->wait_barrier); |
971 | md_wakeup_thread(mddev->thread); |
972 | kfree(plug); |
973 | return; |
974 | } |
975 | |
976 | /* we aren't scheduling, so we can do the write-out directly. */ |
977 | bio = bio_list_get(&plug->pending); |
978 | bitmap_unplug(mddev->bitmap); |
979 | wake_up(&conf->wait_barrier); |
980 | |
981 | while (bio) { /* submit pending writes */ |
982 | struct bio *next = bio->bi_next; |
983 | bio->bi_next = NULL; |
984 | generic_make_request(bio); |
985 | bio = next; |
986 | } |
987 | kfree(plug); |
988 | } |
989 | |
990 | static void make_request(struct mddev *mddev, struct bio * bio) |
991 | { |
992 | struct r1conf *conf = mddev->private; |
993 | struct raid1_info *mirror; |
994 | struct r1bio *r1_bio; |
995 | struct bio *read_bio; |
996 | int i, disks; |
997 | struct bitmap *bitmap; |
998 | unsigned long flags; |
999 | const int rw = bio_data_dir(bio); |
1000 | const unsigned long do_sync = (bio->bi_rw & REQ_SYNC); |
1001 | const unsigned long do_flush_fua = (bio->bi_rw & (REQ_FLUSH | REQ_FUA)); |
1002 | const unsigned long do_discard = (bio->bi_rw |
1003 | & (REQ_DISCARD | REQ_SECURE)); |
1004 | const unsigned long do_same = (bio->bi_rw & REQ_WRITE_SAME); |
1005 | struct md_rdev *blocked_rdev; |
1006 | struct blk_plug_cb *cb; |
1007 | struct raid1_plug_cb *plug = NULL; |
1008 | int first_clone; |
1009 | int sectors_handled; |
1010 | int max_sectors; |
1011 | |
1012 | /* |
1013 | * Register the new request and wait if the reconstruction |
1014 | * thread has put up a bar for new requests. |
1015 | * Continue immediately if no resync is active currently. |
1016 | */ |
1017 | |
1018 | md_write_start(mddev, bio); /* wait on superblock update early */ |
1019 | |
1020 | if (bio_data_dir(bio) == WRITE && |
1021 | bio->bi_sector + bio->bi_size/512 > mddev->suspend_lo && |
1022 | bio->bi_sector < mddev->suspend_hi) { |
1023 | /* As the suspend_* range is controlled by |
1024 | * userspace, we want an interruptible |
1025 | * wait. |
1026 | */ |
1027 | DEFINE_WAIT(w); |
1028 | for (;;) { |
1029 | flush_signals(current); |
1030 | prepare_to_wait(&conf->wait_barrier, |
1031 | &w, TASK_INTERRUPTIBLE); |
1032 | if (bio->bi_sector + bio->bi_size/512 <= mddev->suspend_lo || |
1033 | bio->bi_sector >= mddev->suspend_hi) |
1034 | break; |
1035 | schedule(); |
1036 | } |
1037 | finish_wait(&conf->wait_barrier, &w); |
1038 | } |
1039 | |
1040 | wait_barrier(conf); |
1041 | |
1042 | bitmap = mddev->bitmap; |
1043 | |
1044 | /* |
1045 | * make_request() can abort the operation when READA is being |
1046 | * used and no empty request is available. |
1047 | * |
1048 | */ |
1049 | r1_bio = mempool_alloc(conf->r1bio_pool, GFP_NOIO); |
1050 | |
1051 | r1_bio->master_bio = bio; |
1052 | r1_bio->sectors = bio->bi_size >> 9; |
1053 | r1_bio->state = 0; |
1054 | r1_bio->mddev = mddev; |
1055 | r1_bio->sector = bio->bi_sector; |
1056 | |
1057 | /* We might need to issue multiple reads to different |
1058 | * devices if there are bad blocks around, so we keep |
1059 | * track of the number of reads in bio->bi_phys_segments. |
1060 | * If this is 0, there is only one r1_bio and no locking |
1061 | * will be needed when requests complete. If it is |
1062 | * non-zero, then it is the number of not-completed requests. |
1063 | */ |
1064 | bio->bi_phys_segments = 0; |
1065 | clear_bit(BIO_SEG_VALID, &bio->bi_flags); |
1066 | |
1067 | if (rw == READ) { |
1068 | /* |
1069 | * read balancing logic: |
1070 | */ |
1071 | int rdisk; |
1072 | |
1073 | read_again: |
1074 | rdisk = read_balance(conf, r1_bio, &max_sectors); |
1075 | |
1076 | if (rdisk < 0) { |
1077 | /* couldn't find anywhere to read from */ |
1078 | raid_end_bio_io(r1_bio); |
1079 | return; |
1080 | } |
1081 | mirror = conf->mirrors + rdisk; |
1082 | |
1083 | if (test_bit(WriteMostly, &mirror->rdev->flags) && |
1084 | bitmap) { |
1085 | /* Reading from a write-mostly device must |
1086 | * take care not to over-take any writes |
1087 | * that are 'behind' |
1088 | */ |
1089 | wait_event(bitmap->behind_wait, |
1090 | atomic_read(&bitmap->behind_writes) == 0); |
1091 | } |
1092 | r1_bio->read_disk = rdisk; |
1093 | |
1094 | read_bio = bio_clone_mddev(bio, GFP_NOIO, mddev); |
1095 | md_trim_bio(read_bio, r1_bio->sector - bio->bi_sector, |
1096 | max_sectors); |
1097 | |
1098 | r1_bio->bios[rdisk] = read_bio; |
1099 | |
1100 | read_bio->bi_sector = r1_bio->sector + mirror->rdev->data_offset; |
1101 | read_bio->bi_bdev = mirror->rdev->bdev; |
1102 | read_bio->bi_end_io = raid1_end_read_request; |
1103 | read_bio->bi_rw = READ | do_sync; |
1104 | read_bio->bi_private = r1_bio; |
1105 | |
1106 | if (max_sectors < r1_bio->sectors) { |
1107 | /* could not read all from this device, so we will |
1108 | * need another r1_bio. |
1109 | */ |
1110 | |
1111 | sectors_handled = (r1_bio->sector + max_sectors |
1112 | - bio->bi_sector); |
1113 | r1_bio->sectors = max_sectors; |
1114 | spin_lock_irq(&conf->device_lock); |
1115 | if (bio->bi_phys_segments == 0) |
1116 | bio->bi_phys_segments = 2; |
1117 | else |
1118 | bio->bi_phys_segments++; |
1119 | spin_unlock_irq(&conf->device_lock); |
1120 | /* Cannot call generic_make_request directly |
1121 | * as that will be queued in __make_request |
1122 | * and subsequent mempool_alloc might block waiting |
1123 | * for it. So hand bio over to raid1d. |
1124 | */ |
1125 | reschedule_retry(r1_bio); |
1126 | |
1127 | r1_bio = mempool_alloc(conf->r1bio_pool, GFP_NOIO); |
1128 | |
1129 | r1_bio->master_bio = bio; |
1130 | r1_bio->sectors = (bio->bi_size >> 9) - sectors_handled; |
1131 | r1_bio->state = 0; |
1132 | r1_bio->mddev = mddev; |
1133 | r1_bio->sector = bio->bi_sector + sectors_handled; |
1134 | goto read_again; |
1135 | } else |
1136 | generic_make_request(read_bio); |
1137 | return; |
1138 | } |
1139 | |
1140 | /* |
1141 | * WRITE: |
1142 | */ |
1143 | if (conf->pending_count >= max_queued_requests) { |
1144 | md_wakeup_thread(mddev->thread); |
1145 | wait_event(conf->wait_barrier, |
1146 | conf->pending_count < max_queued_requests); |
1147 | } |
1148 | /* first select target devices under rcu_lock and |
1149 | * inc refcount on their rdev. Record them by setting |
1150 | * bios[x] to bio |
1151 | * If there are known/acknowledged bad blocks on any device on |
1152 | * which we have seen a write error, we want to avoid writing those |
1153 | * blocks. |
1154 | * This potentially requires several writes to write around |
1155 | * the bad blocks. Each set of writes gets it's own r1bio |
1156 | * with a set of bios attached. |
1157 | */ |
1158 | |
1159 | disks = conf->raid_disks * 2; |
1160 | retry_write: |
1161 | blocked_rdev = NULL; |
1162 | rcu_read_lock(); |
1163 | max_sectors = r1_bio->sectors; |
1164 | for (i = 0; i < disks; i++) { |
1165 | struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev); |
1166 | if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) { |
1167 | atomic_inc(&rdev->nr_pending); |
1168 | blocked_rdev = rdev; |
1169 | break; |
1170 | } |
1171 | r1_bio->bios[i] = NULL; |
1172 | if (!rdev || test_bit(Faulty, &rdev->flags) |
1173 | || test_bit(Unmerged, &rdev->flags)) { |
1174 | if (i < conf->raid_disks) |
1175 | set_bit(R1BIO_Degraded, &r1_bio->state); |
1176 | continue; |
1177 | } |
1178 | |
1179 | atomic_inc(&rdev->nr_pending); |
1180 | if (test_bit(WriteErrorSeen, &rdev->flags)) { |
1181 | sector_t first_bad; |
1182 | int bad_sectors; |
1183 | int is_bad; |
1184 | |
1185 | is_bad = is_badblock(rdev, r1_bio->sector, |
1186 | max_sectors, |
1187 | &first_bad, &bad_sectors); |
1188 | if (is_bad < 0) { |
1189 | /* mustn't write here until the bad block is |
1190 | * acknowledged*/ |
1191 | set_bit(BlockedBadBlocks, &rdev->flags); |
1192 | blocked_rdev = rdev; |
1193 | break; |
1194 | } |
1195 | if (is_bad && first_bad <= r1_bio->sector) { |
1196 | /* Cannot write here at all */ |
1197 | bad_sectors -= (r1_bio->sector - first_bad); |
1198 | if (bad_sectors < max_sectors) |
1199 | /* mustn't write more than bad_sectors |
1200 | * to other devices yet |
1201 | */ |
1202 | max_sectors = bad_sectors; |
1203 | rdev_dec_pending(rdev, mddev); |
1204 | /* We don't set R1BIO_Degraded as that |
1205 | * only applies if the disk is |
1206 | * missing, so it might be re-added, |
1207 | * and we want to know to recover this |
1208 | * chunk. |
1209 | * In this case the device is here, |
1210 | * and the fact that this chunk is not |
1211 | * in-sync is recorded in the bad |
1212 | * block log |
1213 | */ |
1214 | continue; |
1215 | } |
1216 | if (is_bad) { |
1217 | int good_sectors = first_bad - r1_bio->sector; |
1218 | if (good_sectors < max_sectors) |
1219 | max_sectors = good_sectors; |
1220 | } |
1221 | } |
1222 | r1_bio->bios[i] = bio; |
1223 | } |
1224 | rcu_read_unlock(); |
1225 | |
1226 | if (unlikely(blocked_rdev)) { |
1227 | /* Wait for this device to become unblocked */ |
1228 | int j; |
1229 | |
1230 | for (j = 0; j < i; j++) |
1231 | if (r1_bio->bios[j]) |
1232 | rdev_dec_pending(conf->mirrors[j].rdev, mddev); |
1233 | r1_bio->state = 0; |
1234 | allow_barrier(conf); |
1235 | md_wait_for_blocked_rdev(blocked_rdev, mddev); |
1236 | wait_barrier(conf); |
1237 | goto retry_write; |
1238 | } |
1239 | |
1240 | if (max_sectors < r1_bio->sectors) { |
1241 | /* We are splitting this write into multiple parts, so |
1242 | * we need to prepare for allocating another r1_bio. |
1243 | */ |
1244 | r1_bio->sectors = max_sectors; |
1245 | spin_lock_irq(&conf->device_lock); |
1246 | if (bio->bi_phys_segments == 0) |
1247 | bio->bi_phys_segments = 2; |
1248 | else |
1249 | bio->bi_phys_segments++; |
1250 | spin_unlock_irq(&conf->device_lock); |
1251 | } |
1252 | sectors_handled = r1_bio->sector + max_sectors - bio->bi_sector; |
1253 | |
1254 | atomic_set(&r1_bio->remaining, 1); |
1255 | atomic_set(&r1_bio->behind_remaining, 0); |
1256 | |
1257 | first_clone = 1; |
1258 | for (i = 0; i < disks; i++) { |
1259 | struct bio *mbio; |
1260 | if (!r1_bio->bios[i]) |
1261 | continue; |
1262 | |
1263 | mbio = bio_clone_mddev(bio, GFP_NOIO, mddev); |
1264 | md_trim_bio(mbio, r1_bio->sector - bio->bi_sector, max_sectors); |
1265 | |
1266 | if (first_clone) { |
1267 | /* do behind I/O ? |
1268 | * Not if there are too many, or cannot |
1269 | * allocate memory, or a reader on WriteMostly |
1270 | * is waiting for behind writes to flush */ |
1271 | if (bitmap && |
1272 | (atomic_read(&bitmap->behind_writes) |
1273 | < mddev->bitmap_info.max_write_behind) && |
1274 | !waitqueue_active(&bitmap->behind_wait)) |
1275 | alloc_behind_pages(mbio, r1_bio); |
1276 | |
1277 | bitmap_startwrite(bitmap, r1_bio->sector, |
1278 | r1_bio->sectors, |
1279 | test_bit(R1BIO_BehindIO, |
1280 | &r1_bio->state)); |
1281 | first_clone = 0; |
1282 | } |
1283 | if (r1_bio->behind_bvecs) { |
1284 | struct bio_vec *bvec; |
1285 | int j; |
1286 | |
1287 | /* Yes, I really want the '__' version so that |
1288 | * we clear any unused pointer in the io_vec, rather |
1289 | * than leave them unchanged. This is important |
1290 | * because when we come to free the pages, we won't |
1291 | * know the original bi_idx, so we just free |
1292 | * them all |
1293 | */ |
1294 | __bio_for_each_segment(bvec, mbio, j, 0) |
1295 | bvec->bv_page = r1_bio->behind_bvecs[j].bv_page; |
1296 | if (test_bit(WriteMostly, &conf->mirrors[i].rdev->flags)) |
1297 | atomic_inc(&r1_bio->behind_remaining); |
1298 | } |
1299 | |
1300 | r1_bio->bios[i] = mbio; |
1301 | |
1302 | mbio->bi_sector = (r1_bio->sector + |
1303 | conf->mirrors[i].rdev->data_offset); |
1304 | mbio->bi_bdev = conf->mirrors[i].rdev->bdev; |
1305 | mbio->bi_end_io = raid1_end_write_request; |
1306 | mbio->bi_rw = |
1307 | WRITE | do_flush_fua | do_sync | do_discard | do_same; |
1308 | mbio->bi_private = r1_bio; |
1309 | |
1310 | atomic_inc(&r1_bio->remaining); |
1311 | |
1312 | cb = blk_check_plugged(raid1_unplug, mddev, sizeof(*plug)); |
1313 | if (cb) |
1314 | plug = container_of(cb, struct raid1_plug_cb, cb); |
1315 | else |
1316 | plug = NULL; |
1317 | spin_lock_irqsave(&conf->device_lock, flags); |
1318 | if (plug) { |
1319 | bio_list_add(&plug->pending, mbio); |
1320 | plug->pending_cnt++; |
1321 | } else { |
1322 | bio_list_add(&conf->pending_bio_list, mbio); |
1323 | conf->pending_count++; |
1324 | } |
1325 | spin_unlock_irqrestore(&conf->device_lock, flags); |
1326 | if (!plug) |
1327 | md_wakeup_thread(mddev->thread); |
1328 | } |
1329 | /* Mustn't call r1_bio_write_done before this next test, |
1330 | * as it could result in the bio being freed. |
1331 | */ |
1332 | if (sectors_handled < (bio->bi_size >> 9)) { |
1333 | r1_bio_write_done(r1_bio); |
1334 | /* We need another r1_bio. It has already been counted |
1335 | * in bio->bi_phys_segments |
1336 | */ |
1337 | r1_bio = mempool_alloc(conf->r1bio_pool, GFP_NOIO); |
1338 | r1_bio->master_bio = bio; |
1339 | r1_bio->sectors = (bio->bi_size >> 9) - sectors_handled; |
1340 | r1_bio->state = 0; |
1341 | r1_bio->mddev = mddev; |
1342 | r1_bio->sector = bio->bi_sector + sectors_handled; |
1343 | goto retry_write; |
1344 | } |
1345 | |
1346 | r1_bio_write_done(r1_bio); |
1347 | |
1348 | /* In case raid1d snuck in to freeze_array */ |
1349 | wake_up(&conf->wait_barrier); |
1350 | } |
1351 | |
1352 | static void status(struct seq_file *seq, struct mddev *mddev) |
1353 | { |
1354 | struct r1conf *conf = mddev->private; |
1355 | int i; |
1356 | |
1357 | seq_printf(seq, " [%d/%d] [", conf->raid_disks, |
1358 | conf->raid_disks - mddev->degraded); |
1359 | rcu_read_lock(); |
1360 | for (i = 0; i < conf->raid_disks; i++) { |
1361 | struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev); |
1362 | seq_printf(seq, "%s", |
1363 | rdev && test_bit(In_sync, &rdev->flags) ? "U" : "_"); |
1364 | } |
1365 | rcu_read_unlock(); |
1366 | seq_printf(seq, "]"); |
1367 | } |
1368 | |
1369 | |
1370 | static void error(struct mddev *mddev, struct md_rdev *rdev) |
1371 | { |
1372 | char b[BDEVNAME_SIZE]; |
1373 | struct r1conf *conf = mddev->private; |
1374 | |
1375 | /* |
1376 | * If it is not operational, then we have already marked it as dead |
1377 | * else if it is the last working disks, ignore the error, let the |
1378 | * next level up know. |
1379 | * else mark the drive as failed |
1380 | */ |
1381 | if (test_bit(In_sync, &rdev->flags) |
1382 | && (conf->raid_disks - mddev->degraded) == 1) { |
1383 | /* |
1384 | * Don't fail the drive, act as though we were just a |
1385 | * normal single drive. |
1386 | * However don't try a recovery from this drive as |
1387 | * it is very likely to fail. |
1388 | */ |
1389 | conf->recovery_disabled = mddev->recovery_disabled; |
1390 | return; |
1391 | } |
1392 | set_bit(Blocked, &rdev->flags); |
1393 | if (test_and_clear_bit(In_sync, &rdev->flags)) { |
1394 | unsigned long flags; |
1395 | spin_lock_irqsave(&conf->device_lock, flags); |
1396 | mddev->degraded++; |
1397 | set_bit(Faulty, &rdev->flags); |
1398 | spin_unlock_irqrestore(&conf->device_lock, flags); |
1399 | /* |
1400 | * if recovery is running, make sure it aborts. |
1401 | */ |
1402 | set_bit(MD_RECOVERY_INTR, &mddev->recovery); |
1403 | } else |
1404 | set_bit(Faulty, &rdev->flags); |
1405 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
1406 | printk(KERN_ALERT |
1407 | "md/raid1:%s: Disk failure on %s, disabling device.\n" |
1408 | "md/raid1:%s: Operation continuing on %d devices.\n", |
1409 | mdname(mddev), bdevname(rdev->bdev, b), |
1410 | mdname(mddev), conf->raid_disks - mddev->degraded); |
1411 | } |
1412 | |
1413 | static void print_conf(struct r1conf *conf) |
1414 | { |
1415 | int i; |
1416 | |
1417 | printk(KERN_DEBUG "RAID1 conf printout:\n"); |
1418 | if (!conf) { |
1419 | printk(KERN_DEBUG "(!conf)\n"); |
1420 | return; |
1421 | } |
1422 | printk(KERN_DEBUG " --- wd:%d rd:%d\n", conf->raid_disks - conf->mddev->degraded, |
1423 | conf->raid_disks); |
1424 | |
1425 | rcu_read_lock(); |
1426 | for (i = 0; i < conf->raid_disks; i++) { |
1427 | char b[BDEVNAME_SIZE]; |
1428 | struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev); |
1429 | if (rdev) |
1430 | printk(KERN_DEBUG " disk %d, wo:%d, o:%d, dev:%s\n", |
1431 | i, !test_bit(In_sync, &rdev->flags), |
1432 | !test_bit(Faulty, &rdev->flags), |
1433 | bdevname(rdev->bdev,b)); |
1434 | } |
1435 | rcu_read_unlock(); |
1436 | } |
1437 | |
1438 | static void close_sync(struct r1conf *conf) |
1439 | { |
1440 | wait_barrier(conf); |
1441 | allow_barrier(conf); |
1442 | |
1443 | mempool_destroy(conf->r1buf_pool); |
1444 | conf->r1buf_pool = NULL; |
1445 | } |
1446 | |
1447 | static int raid1_spare_active(struct mddev *mddev) |
1448 | { |
1449 | int i; |
1450 | struct r1conf *conf = mddev->private; |
1451 | int count = 0; |
1452 | unsigned long flags; |
1453 | |
1454 | /* |
1455 | * Find all failed disks within the RAID1 configuration |
1456 | * and mark them readable. |
1457 | * Called under mddev lock, so rcu protection not needed. |
1458 | */ |
1459 | for (i = 0; i < conf->raid_disks; i++) { |
1460 | struct md_rdev *rdev = conf->mirrors[i].rdev; |
1461 | struct md_rdev *repl = conf->mirrors[conf->raid_disks + i].rdev; |
1462 | if (repl |
1463 | && repl->recovery_offset == MaxSector |
1464 | && !test_bit(Faulty, &repl->flags) |
1465 | && !test_and_set_bit(In_sync, &repl->flags)) { |
1466 | /* replacement has just become active */ |
1467 | if (!rdev || |
1468 | !test_and_clear_bit(In_sync, &rdev->flags)) |
1469 | count++; |
1470 | if (rdev) { |
1471 | /* Replaced device not technically |
1472 | * faulty, but we need to be sure |
1473 | * it gets removed and never re-added |
1474 | */ |
1475 | set_bit(Faulty, &rdev->flags); |
1476 | sysfs_notify_dirent_safe( |
1477 | rdev->sysfs_state); |
1478 | } |
1479 | } |
1480 | if (rdev |
1481 | && !test_bit(Faulty, &rdev->flags) |
1482 | && !test_and_set_bit(In_sync, &rdev->flags)) { |
1483 | count++; |
1484 | sysfs_notify_dirent_safe(rdev->sysfs_state); |
1485 | } |
1486 | } |
1487 | spin_lock_irqsave(&conf->device_lock, flags); |
1488 | mddev->degraded -= count; |
1489 | spin_unlock_irqrestore(&conf->device_lock, flags); |
1490 | |
1491 | print_conf(conf); |
1492 | return count; |
1493 | } |
1494 | |
1495 | |
1496 | static int raid1_add_disk(struct mddev *mddev, struct md_rdev *rdev) |
1497 | { |
1498 | struct r1conf *conf = mddev->private; |
1499 | int err = -EEXIST; |
1500 | int mirror = 0; |
1501 | struct raid1_info *p; |
1502 | int first = 0; |
1503 | int last = conf->raid_disks - 1; |
1504 | struct request_queue *q = bdev_get_queue(rdev->bdev); |
1505 | |
1506 | if (mddev->recovery_disabled == conf->recovery_disabled) |
1507 | return -EBUSY; |
1508 | |
1509 | if (rdev->raid_disk >= 0) |
1510 | first = last = rdev->raid_disk; |
1511 | |
1512 | if (q->merge_bvec_fn) { |
1513 | set_bit(Unmerged, &rdev->flags); |
1514 | mddev->merge_check_needed = 1; |
1515 | } |
1516 | |
1517 | for (mirror = first; mirror <= last; mirror++) { |
1518 | p = conf->mirrors+mirror; |
1519 | if (!p->rdev) { |
1520 | |
1521 | disk_stack_limits(mddev->gendisk, rdev->bdev, |
1522 | rdev->data_offset << 9); |
1523 | |
1524 | p->head_position = 0; |
1525 | rdev->raid_disk = mirror; |
1526 | err = 0; |
1527 | /* As all devices are equivalent, we don't need a full recovery |
1528 | * if this was recently any drive of the array |
1529 | */ |
1530 | if (rdev->saved_raid_disk < 0) |
1531 | conf->fullsync = 1; |
1532 | rcu_assign_pointer(p->rdev, rdev); |
1533 | break; |
1534 | } |
1535 | if (test_bit(WantReplacement, &p->rdev->flags) && |
1536 | p[conf->raid_disks].rdev == NULL) { |
1537 | /* Add this device as a replacement */ |
1538 | clear_bit(In_sync, &rdev->flags); |
1539 | set_bit(Replacement, &rdev->flags); |
1540 | rdev->raid_disk = mirror; |
1541 | err = 0; |
1542 | conf->fullsync = 1; |
1543 | rcu_assign_pointer(p[conf->raid_disks].rdev, rdev); |
1544 | break; |
1545 | } |
1546 | } |
1547 | if (err == 0 && test_bit(Unmerged, &rdev->flags)) { |
1548 | /* Some requests might not have seen this new |
1549 | * merge_bvec_fn. We must wait for them to complete |
1550 | * before merging the device fully. |
1551 | * First we make sure any code which has tested |
1552 | * our function has submitted the request, then |
1553 | * we wait for all outstanding requests to complete. |
1554 | */ |
1555 | synchronize_sched(); |
1556 | raise_barrier(conf); |
1557 | lower_barrier(conf); |
1558 | clear_bit(Unmerged, &rdev->flags); |
1559 | } |
1560 | md_integrity_add_rdev(rdev, mddev); |
1561 | if (blk_queue_discard(bdev_get_queue(rdev->bdev))) |
1562 | queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mddev->queue); |
1563 | print_conf(conf); |
1564 | return err; |
1565 | } |
1566 | |
1567 | static int raid1_remove_disk(struct mddev *mddev, struct md_rdev *rdev) |
1568 | { |
1569 | struct r1conf *conf = mddev->private; |
1570 | int err = 0; |
1571 | int number = rdev->raid_disk; |
1572 | struct raid1_info *p = conf->mirrors + number; |
1573 | |
1574 | if (rdev != p->rdev) |
1575 | p = conf->mirrors + conf->raid_disks + number; |
1576 | |
1577 | print_conf(conf); |
1578 | if (rdev == p->rdev) { |
1579 | if (test_bit(In_sync, &rdev->flags) || |
1580 | atomic_read(&rdev->nr_pending)) { |
1581 | err = -EBUSY; |
1582 | goto abort; |
1583 | } |
1584 | /* Only remove non-faulty devices if recovery |
1585 | * is not possible. |
1586 | */ |
1587 | if (!test_bit(Faulty, &rdev->flags) && |
1588 | mddev->recovery_disabled != conf->recovery_disabled && |
1589 | mddev->degraded < conf->raid_disks) { |
1590 | err = -EBUSY; |
1591 | goto abort; |
1592 | } |
1593 | p->rdev = NULL; |
1594 | synchronize_rcu(); |
1595 | if (atomic_read(&rdev->nr_pending)) { |
1596 | /* lost the race, try later */ |
1597 | err = -EBUSY; |
1598 | p->rdev = rdev; |
1599 | goto abort; |
1600 | } else if (conf->mirrors[conf->raid_disks + number].rdev) { |
1601 | /* We just removed a device that is being replaced. |
1602 | * Move down the replacement. We drain all IO before |
1603 | * doing this to avoid confusion. |
1604 | */ |
1605 | struct md_rdev *repl = |
1606 | conf->mirrors[conf->raid_disks + number].rdev; |
1607 | raise_barrier(conf); |
1608 | clear_bit(Replacement, &repl->flags); |
1609 | p->rdev = repl; |
1610 | conf->mirrors[conf->raid_disks + number].rdev = NULL; |
1611 | lower_barrier(conf); |
1612 | clear_bit(WantReplacement, &rdev->flags); |
1613 | } else |
1614 | clear_bit(WantReplacement, &rdev->flags); |
1615 | err = md_integrity_register(mddev); |
1616 | } |
1617 | abort: |
1618 | |
1619 | print_conf(conf); |
1620 | return err; |
1621 | } |
1622 | |
1623 | |
1624 | static void end_sync_read(struct bio *bio, int error) |
1625 | { |
1626 | struct r1bio *r1_bio = bio->bi_private; |
1627 | |
1628 | update_head_pos(r1_bio->read_disk, r1_bio); |
1629 | |
1630 | /* |
1631 | * we have read a block, now it needs to be re-written, |
1632 | * or re-read if the read failed. |
1633 | * We don't do much here, just schedule handling by raid1d |
1634 | */ |
1635 | if (test_bit(BIO_UPTODATE, &bio->bi_flags)) |
1636 | set_bit(R1BIO_Uptodate, &r1_bio->state); |
1637 | |
1638 | if (atomic_dec_and_test(&r1_bio->remaining)) |
1639 | reschedule_retry(r1_bio); |
1640 | } |
1641 | |
1642 | static void end_sync_write(struct bio *bio, int error) |
1643 | { |
1644 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); |
1645 | struct r1bio *r1_bio = bio->bi_private; |
1646 | struct mddev *mddev = r1_bio->mddev; |
1647 | struct r1conf *conf = mddev->private; |
1648 | int mirror=0; |
1649 | sector_t first_bad; |
1650 | int bad_sectors; |
1651 | |
1652 | mirror = find_bio_disk(r1_bio, bio); |
1653 | |
1654 | if (!uptodate) { |
1655 | sector_t sync_blocks = 0; |
1656 | sector_t s = r1_bio->sector; |
1657 | long sectors_to_go = r1_bio->sectors; |
1658 | /* make sure these bits doesn't get cleared. */ |
1659 | do { |
1660 | bitmap_end_sync(mddev->bitmap, s, |
1661 | &sync_blocks, 1); |
1662 | s += sync_blocks; |
1663 | sectors_to_go -= sync_blocks; |
1664 | } while (sectors_to_go > 0); |
1665 | set_bit(WriteErrorSeen, |
1666 | &conf->mirrors[mirror].rdev->flags); |
1667 | if (!test_and_set_bit(WantReplacement, |
1668 | &conf->mirrors[mirror].rdev->flags)) |
1669 | set_bit(MD_RECOVERY_NEEDED, & |
1670 | mddev->recovery); |
1671 | set_bit(R1BIO_WriteError, &r1_bio->state); |
1672 | } else if (is_badblock(conf->mirrors[mirror].rdev, |
1673 | r1_bio->sector, |
1674 | r1_bio->sectors, |
1675 | &first_bad, &bad_sectors) && |
1676 | !is_badblock(conf->mirrors[r1_bio->read_disk].rdev, |
1677 | r1_bio->sector, |
1678 | r1_bio->sectors, |
1679 | &first_bad, &bad_sectors) |
1680 | ) |
1681 | set_bit(R1BIO_MadeGood, &r1_bio->state); |
1682 | |
1683 | if (atomic_dec_and_test(&r1_bio->remaining)) { |
1684 | int s = r1_bio->sectors; |
1685 | if (test_bit(R1BIO_MadeGood, &r1_bio->state) || |
1686 | test_bit(R1BIO_WriteError, &r1_bio->state)) |
1687 | reschedule_retry(r1_bio); |
1688 | else { |
1689 | put_buf(r1_bio); |
1690 | md_done_sync(mddev, s, uptodate); |
1691 | } |
1692 | } |
1693 | } |
1694 | |
1695 | static int r1_sync_page_io(struct md_rdev *rdev, sector_t sector, |
1696 | int sectors, struct page *page, int rw) |
1697 | { |
1698 | if (sync_page_io(rdev, sector, sectors << 9, page, rw, false)) |
1699 | /* success */ |
1700 | return 1; |
1701 | if (rw == WRITE) { |
1702 | set_bit(WriteErrorSeen, &rdev->flags); |
1703 | if (!test_and_set_bit(WantReplacement, |
1704 | &rdev->flags)) |
1705 | set_bit(MD_RECOVERY_NEEDED, & |
1706 | rdev->mddev->recovery); |
1707 | } |
1708 | /* need to record an error - either for the block or the device */ |
1709 | if (!rdev_set_badblocks(rdev, sector, sectors, 0)) |
1710 | md_error(rdev->mddev, rdev); |
1711 | return 0; |
1712 | } |
1713 | |
1714 | static int fix_sync_read_error(struct r1bio *r1_bio) |
1715 | { |
1716 | /* Try some synchronous reads of other devices to get |
1717 | * good data, much like with normal read errors. Only |
1718 | * read into the pages we already have so we don't |
1719 | * need to re-issue the read request. |
1720 | * We don't need to freeze the array, because being in an |
1721 | * active sync request, there is no normal IO, and |
1722 | * no overlapping syncs. |
1723 | * We don't need to check is_badblock() again as we |
1724 | * made sure that anything with a bad block in range |
1725 | * will have bi_end_io clear. |
1726 | */ |
1727 | struct mddev *mddev = r1_bio->mddev; |
1728 | struct r1conf *conf = mddev->private; |
1729 | struct bio *bio = r1_bio->bios[r1_bio->read_disk]; |
1730 | sector_t sect = r1_bio->sector; |
1731 | int sectors = r1_bio->sectors; |
1732 | int idx = 0; |
1733 | |
1734 | while(sectors) { |
1735 | int s = sectors; |
1736 | int d = r1_bio->read_disk; |
1737 | int success = 0; |
1738 | struct md_rdev *rdev; |
1739 | int start; |
1740 | |
1741 | if (s > (PAGE_SIZE>>9)) |
1742 | s = PAGE_SIZE >> 9; |
1743 | do { |
1744 | if (r1_bio->bios[d]->bi_end_io == end_sync_read) { |
1745 | /* No rcu protection needed here devices |
1746 | * can only be removed when no resync is |
1747 | * active, and resync is currently active |
1748 | */ |
1749 | rdev = conf->mirrors[d].rdev; |
1750 | if (sync_page_io(rdev, sect, s<<9, |
1751 | bio->bi_io_vec[idx].bv_page, |
1752 | READ, false)) { |
1753 | success = 1; |
1754 | break; |
1755 | } |
1756 | } |
1757 | d++; |
1758 | if (d == conf->raid_disks * 2) |
1759 | d = 0; |
1760 | } while (!success && d != r1_bio->read_disk); |
1761 | |
1762 | if (!success) { |
1763 | char b[BDEVNAME_SIZE]; |
1764 | int abort = 0; |
1765 | /* Cannot read from anywhere, this block is lost. |
1766 | * Record a bad block on each device. If that doesn't |
1767 | * work just disable and interrupt the recovery. |
1768 | * Don't fail devices as that won't really help. |
1769 | */ |
1770 | printk(KERN_ALERT "md/raid1:%s: %s: unrecoverable I/O read error" |
1771 | " for block %llu\n", |
1772 | mdname(mddev), |
1773 | bdevname(bio->bi_bdev, b), |
1774 | (unsigned long long)r1_bio->sector); |
1775 | for (d = 0; d < conf->raid_disks * 2; d++) { |
1776 | rdev = conf->mirrors[d].rdev; |
1777 | if (!rdev || test_bit(Faulty, &rdev->flags)) |
1778 | continue; |
1779 | if (!rdev_set_badblocks(rdev, sect, s, 0)) |
1780 | abort = 1; |
1781 | } |
1782 | if (abort) { |
1783 | conf->recovery_disabled = |
1784 | mddev->recovery_disabled; |
1785 | set_bit(MD_RECOVERY_INTR, &mddev->recovery); |
1786 | md_done_sync(mddev, r1_bio->sectors, 0); |
1787 | put_buf(r1_bio); |
1788 | return 0; |
1789 | } |
1790 | /* Try next page */ |
1791 | sectors -= s; |
1792 | sect += s; |
1793 | idx++; |
1794 | continue; |
1795 | } |
1796 | |
1797 | start = d; |
1798 | /* write it back and re-read */ |
1799 | while (d != r1_bio->read_disk) { |
1800 | if (d == 0) |
1801 | d = conf->raid_disks * 2; |
1802 | d--; |
1803 | if (r1_bio->bios[d]->bi_end_io != end_sync_read) |
1804 | continue; |
1805 | rdev = conf->mirrors[d].rdev; |
1806 | if (r1_sync_page_io(rdev, sect, s, |
1807 | bio->bi_io_vec[idx].bv_page, |
1808 | WRITE) == 0) { |
1809 | r1_bio->bios[d]->bi_end_io = NULL; |
1810 | rdev_dec_pending(rdev, mddev); |
1811 | } |
1812 | } |
1813 | d = start; |
1814 | while (d != r1_bio->read_disk) { |
1815 | if (d == 0) |
1816 | d = conf->raid_disks * 2; |
1817 | d--; |
1818 | if (r1_bio->bios[d]->bi_end_io != end_sync_read) |
1819 | continue; |
1820 | rdev = conf->mirrors[d].rdev; |
1821 | if (r1_sync_page_io(rdev, sect, s, |
1822 | bio->bi_io_vec[idx].bv_page, |
1823 | READ) != 0) |
1824 | atomic_add(s, &rdev->corrected_errors); |
1825 | } |
1826 | sectors -= s; |
1827 | sect += s; |
1828 | idx ++; |
1829 | } |
1830 | set_bit(R1BIO_Uptodate, &r1_bio->state); |
1831 | set_bit(BIO_UPTODATE, &bio->bi_flags); |
1832 | return 1; |
1833 | } |
1834 | |
1835 | static int process_checks(struct r1bio *r1_bio) |
1836 | { |
1837 | /* We have read all readable devices. If we haven't |
1838 | * got the block, then there is no hope left. |
1839 | * If we have, then we want to do a comparison |
1840 | * and skip the write if everything is the same. |
1841 | * If any blocks failed to read, then we need to |
1842 | * attempt an over-write |
1843 | */ |
1844 | struct mddev *mddev = r1_bio->mddev; |
1845 | struct r1conf *conf = mddev->private; |
1846 | int primary; |
1847 | int i; |
1848 | int vcnt; |
1849 | |
1850 | for (primary = 0; primary < conf->raid_disks * 2; primary++) |
1851 | if (r1_bio->bios[primary]->bi_end_io == end_sync_read && |
1852 | test_bit(BIO_UPTODATE, &r1_bio->bios[primary]->bi_flags)) { |
1853 | r1_bio->bios[primary]->bi_end_io = NULL; |
1854 | rdev_dec_pending(conf->mirrors[primary].rdev, mddev); |
1855 | break; |
1856 | } |
1857 | r1_bio->read_disk = primary; |
1858 | vcnt = (r1_bio->sectors + PAGE_SIZE / 512 - 1) >> (PAGE_SHIFT - 9); |
1859 | for (i = 0; i < conf->raid_disks * 2; i++) { |
1860 | int j; |
1861 | struct bio *pbio = r1_bio->bios[primary]; |
1862 | struct bio *sbio = r1_bio->bios[i]; |
1863 | int size; |
1864 | |
1865 | if (r1_bio->bios[i]->bi_end_io != end_sync_read) |
1866 | continue; |
1867 | |
1868 | if (test_bit(BIO_UPTODATE, &sbio->bi_flags)) { |
1869 | for (j = vcnt; j-- ; ) { |
1870 | struct page *p, *s; |
1871 | p = pbio->bi_io_vec[j].bv_page; |
1872 | s = sbio->bi_io_vec[j].bv_page; |
1873 | if (memcmp(page_address(p), |
1874 | page_address(s), |
1875 | sbio->bi_io_vec[j].bv_len)) |
1876 | break; |
1877 | } |
1878 | } else |
1879 | j = 0; |
1880 | if (j >= 0) |
1881 | atomic64_add(r1_bio->sectors, &mddev->resync_mismatches); |
1882 | if (j < 0 || (test_bit(MD_RECOVERY_CHECK, &mddev->recovery) |
1883 | && test_bit(BIO_UPTODATE, &sbio->bi_flags))) { |
1884 | /* No need to write to this device. */ |
1885 | sbio->bi_end_io = NULL; |
1886 | rdev_dec_pending(conf->mirrors[i].rdev, mddev); |
1887 | continue; |
1888 | } |
1889 | /* fixup the bio for reuse */ |
1890 | sbio->bi_vcnt = vcnt; |
1891 | sbio->bi_size = r1_bio->sectors << 9; |
1892 | sbio->bi_idx = 0; |
1893 | sbio->bi_phys_segments = 0; |
1894 | sbio->bi_flags &= ~(BIO_POOL_MASK - 1); |
1895 | sbio->bi_flags |= 1 << BIO_UPTODATE; |
1896 | sbio->bi_next = NULL; |
1897 | sbio->bi_sector = r1_bio->sector + |
1898 | conf->mirrors[i].rdev->data_offset; |
1899 | sbio->bi_bdev = conf->mirrors[i].rdev->bdev; |
1900 | size = sbio->bi_size; |
1901 | for (j = 0; j < vcnt ; j++) { |
1902 | struct bio_vec *bi; |
1903 | bi = &sbio->bi_io_vec[j]; |
1904 | bi->bv_offset = 0; |
1905 | if (size > PAGE_SIZE) |
1906 | bi->bv_len = PAGE_SIZE; |
1907 | else |
1908 | bi->bv_len = size; |
1909 | size -= PAGE_SIZE; |
1910 | memcpy(page_address(bi->bv_page), |
1911 | page_address(pbio->bi_io_vec[j].bv_page), |
1912 | PAGE_SIZE); |
1913 | } |
1914 | } |
1915 | return 0; |
1916 | } |
1917 | |
1918 | static void sync_request_write(struct mddev *mddev, struct r1bio *r1_bio) |
1919 | { |
1920 | struct r1conf *conf = mddev->private; |
1921 | int i; |
1922 | int disks = conf->raid_disks * 2; |
1923 | struct bio *bio, *wbio; |
1924 | |
1925 | bio = r1_bio->bios[r1_bio->read_disk]; |
1926 | |
1927 | if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) |
1928 | /* ouch - failed to read all of that. */ |
1929 | if (!fix_sync_read_error(r1_bio)) |
1930 | return; |
1931 | |
1932 | if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) |
1933 | if (process_checks(r1_bio) < 0) |
1934 | return; |
1935 | /* |
1936 | * schedule writes |
1937 | */ |
1938 | atomic_set(&r1_bio->remaining, 1); |
1939 | for (i = 0; i < disks ; i++) { |
1940 | wbio = r1_bio->bios[i]; |
1941 | if (wbio->bi_end_io == NULL || |
1942 | (wbio->bi_end_io == end_sync_read && |
1943 | (i == r1_bio->read_disk || |
1944 | !test_bit(MD_RECOVERY_SYNC, &mddev->recovery)))) |
1945 | continue; |
1946 | |
1947 | wbio->bi_rw = WRITE; |
1948 | wbio->bi_end_io = end_sync_write; |
1949 | atomic_inc(&r1_bio->remaining); |
1950 | md_sync_acct(conf->mirrors[i].rdev->bdev, wbio->bi_size >> 9); |
1951 | |
1952 | generic_make_request(wbio); |
1953 | } |
1954 | |
1955 | if (atomic_dec_and_test(&r1_bio->remaining)) { |
1956 | /* if we're here, all write(s) have completed, so clean up */ |
1957 | int s = r1_bio->sectors; |
1958 | if (test_bit(R1BIO_MadeGood, &r1_bio->state) || |
1959 | test_bit(R1BIO_WriteError, &r1_bio->state)) |
1960 | reschedule_retry(r1_bio); |
1961 | else { |
1962 | put_buf(r1_bio); |
1963 | md_done_sync(mddev, s, 1); |
1964 | } |
1965 | } |
1966 | } |
1967 | |
1968 | /* |
1969 | * This is a kernel thread which: |
1970 | * |
1971 | * 1. Retries failed read operations on working mirrors. |
1972 | * 2. Updates the raid superblock when problems encounter. |
1973 | * 3. Performs writes following reads for array synchronising. |
1974 | */ |
1975 | |
1976 | static void fix_read_error(struct r1conf *conf, int read_disk, |
1977 | sector_t sect, int sectors) |
1978 | { |
1979 | struct mddev *mddev = conf->mddev; |
1980 | while(sectors) { |
1981 | int s = sectors; |
1982 | int d = read_disk; |
1983 | int success = 0; |
1984 | int start; |
1985 | struct md_rdev *rdev; |
1986 | |
1987 | if (s > (PAGE_SIZE>>9)) |
1988 | s = PAGE_SIZE >> 9; |
1989 | |
1990 | do { |
1991 | /* Note: no rcu protection needed here |
1992 | * as this is synchronous in the raid1d thread |
1993 | * which is the thread that might remove |
1994 | * a device. If raid1d ever becomes multi-threaded.... |
1995 | */ |
1996 | sector_t first_bad; |
1997 | int bad_sectors; |
1998 | |
1999 | rdev = conf->mirrors[d].rdev; |
2000 | if (rdev && |
2001 | (test_bit(In_sync, &rdev->flags) || |
2002 | (!test_bit(Faulty, &rdev->flags) && |
2003 | rdev->recovery_offset >= sect + s)) && |
2004 | is_badblock(rdev, sect, s, |
2005 | &first_bad, &bad_sectors) == 0 && |
2006 | sync_page_io(rdev, sect, s<<9, |
2007 | conf->tmppage, READ, false)) |
2008 | success = 1; |
2009 | else { |
2010 | d++; |
2011 | if (d == conf->raid_disks * 2) |
2012 | d = 0; |
2013 | } |
2014 | } while (!success && d != read_disk); |
2015 | |
2016 | if (!success) { |
2017 | /* Cannot read from anywhere - mark it bad */ |
2018 | struct md_rdev *rdev = conf->mirrors[read_disk].rdev; |
2019 | if (!rdev_set_badblocks(rdev, sect, s, 0)) |
2020 | md_error(mddev, rdev); |
2021 | break; |
2022 | } |
2023 | /* write it back and re-read */ |
2024 | start = d; |
2025 | while (d != read_disk) { |
2026 | if (d==0) |
2027 | d = conf->raid_disks * 2; |
2028 | d--; |
2029 | rdev = conf->mirrors[d].rdev; |
2030 | if (rdev && |
2031 | test_bit(In_sync, &rdev->flags)) |
2032 | r1_sync_page_io(rdev, sect, s, |
2033 | conf->tmppage, WRITE); |
2034 | } |
2035 | d = start; |
2036 | while (d != read_disk) { |
2037 | char b[BDEVNAME_SIZE]; |
2038 | if (d==0) |
2039 | d = conf->raid_disks * 2; |
2040 | d--; |
2041 | rdev = conf->mirrors[d].rdev; |
2042 | if (rdev && |
2043 | test_bit(In_sync, &rdev->flags)) { |
2044 | if (r1_sync_page_io(rdev, sect, s, |
2045 | conf->tmppage, READ)) { |
2046 | atomic_add(s, &rdev->corrected_errors); |
2047 | printk(KERN_INFO |
2048 | "md/raid1:%s: read error corrected " |
2049 | "(%d sectors at %llu on %s)\n", |
2050 | mdname(mddev), s, |
2051 | (unsigned long long)(sect + |
2052 | rdev->data_offset), |
2053 | bdevname(rdev->bdev, b)); |
2054 | } |
2055 | } |
2056 | } |
2057 | sectors -= s; |
2058 | sect += s; |
2059 | } |
2060 | } |
2061 | |
2062 | static void bi_complete(struct bio *bio, int error) |
2063 | { |
2064 | complete((struct completion *)bio->bi_private); |
2065 | } |
2066 | |
2067 | static int submit_bio_wait(int rw, struct bio *bio) |
2068 | { |
2069 | struct completion event; |
2070 | rw |= REQ_SYNC; |
2071 | |
2072 | init_completion(&event); |
2073 | bio->bi_private = &event; |
2074 | bio->bi_end_io = bi_complete; |
2075 | submit_bio(rw, bio); |
2076 | wait_for_completion(&event); |
2077 | |
2078 | return test_bit(BIO_UPTODATE, &bio->bi_flags); |
2079 | } |
2080 | |
2081 | static int narrow_write_error(struct r1bio *r1_bio, int i) |
2082 | { |
2083 | struct mddev *mddev = r1_bio->mddev; |
2084 | struct r1conf *conf = mddev->private; |
2085 | struct md_rdev *rdev = conf->mirrors[i].rdev; |
2086 | int vcnt, idx; |
2087 | struct bio_vec *vec; |
2088 | |
2089 | /* bio has the data to be written to device 'i' where |
2090 | * we just recently had a write error. |
2091 | * We repeatedly clone the bio and trim down to one block, |
2092 | * then try the write. Where the write fails we record |
2093 | * a bad block. |
2094 | * It is conceivable that the bio doesn't exactly align with |
2095 | * blocks. We must handle this somehow. |
2096 | * |
2097 | * We currently own a reference on the rdev. |
2098 | */ |
2099 | |
2100 | int block_sectors; |
2101 | sector_t sector; |
2102 | int sectors; |
2103 | int sect_to_write = r1_bio->sectors; |
2104 | int ok = 1; |
2105 | |
2106 | if (rdev->badblocks.shift < 0) |
2107 | return 0; |
2108 | |
2109 | block_sectors = 1 << rdev->badblocks.shift; |
2110 | sector = r1_bio->sector; |
2111 | sectors = ((sector + block_sectors) |
2112 | & ~(sector_t)(block_sectors - 1)) |
2113 | - sector; |
2114 | |
2115 | if (test_bit(R1BIO_BehindIO, &r1_bio->state)) { |
2116 | vcnt = r1_bio->behind_page_count; |
2117 | vec = r1_bio->behind_bvecs; |
2118 | idx = 0; |
2119 | while (vec[idx].bv_page == NULL) |
2120 | idx++; |
2121 | } else { |
2122 | vcnt = r1_bio->master_bio->bi_vcnt; |
2123 | vec = r1_bio->master_bio->bi_io_vec; |
2124 | idx = r1_bio->master_bio->bi_idx; |
2125 | } |
2126 | while (sect_to_write) { |
2127 | struct bio *wbio; |
2128 | if (sectors > sect_to_write) |
2129 | sectors = sect_to_write; |
2130 | /* Write at 'sector' for 'sectors'*/ |
2131 | |
2132 | wbio = bio_alloc_mddev(GFP_NOIO, vcnt, mddev); |
2133 | memcpy(wbio->bi_io_vec, vec, vcnt * sizeof(struct bio_vec)); |
2134 | wbio->bi_sector = r1_bio->sector; |
2135 | wbio->bi_rw = WRITE; |
2136 | wbio->bi_vcnt = vcnt; |
2137 | wbio->bi_size = r1_bio->sectors << 9; |
2138 | wbio->bi_idx = idx; |
2139 | |
2140 | md_trim_bio(wbio, sector - r1_bio->sector, sectors); |
2141 | wbio->bi_sector += rdev->data_offset; |
2142 | wbio->bi_bdev = rdev->bdev; |
2143 | if (submit_bio_wait(WRITE, wbio) == 0) |
2144 | /* failure! */ |
2145 | ok = rdev_set_badblocks(rdev, sector, |
2146 | sectors, 0) |
2147 | && ok; |
2148 | |
2149 | bio_put(wbio); |
2150 | sect_to_write -= sectors; |
2151 | sector += sectors; |
2152 | sectors = block_sectors; |
2153 | } |
2154 | return ok; |
2155 | } |
2156 | |
2157 | static void handle_sync_write_finished(struct r1conf *conf, struct r1bio *r1_bio) |
2158 | { |
2159 | int m; |
2160 | int s = r1_bio->sectors; |
2161 | for (m = 0; m < conf->raid_disks * 2 ; m++) { |
2162 | struct md_rdev *rdev = conf->mirrors[m].rdev; |
2163 | struct bio *bio = r1_bio->bios[m]; |
2164 | if (bio->bi_end_io == NULL) |
2165 | continue; |
2166 | if (test_bit(BIO_UPTODATE, &bio->bi_flags) && |
2167 | test_bit(R1BIO_MadeGood, &r1_bio->state)) { |
2168 | rdev_clear_badblocks(rdev, r1_bio->sector, s, 0); |
2169 | } |
2170 | if (!test_bit(BIO_UPTODATE, &bio->bi_flags) && |
2171 | test_bit(R1BIO_WriteError, &r1_bio->state)) { |
2172 | if (!rdev_set_badblocks(rdev, r1_bio->sector, s, 0)) |
2173 | md_error(conf->mddev, rdev); |
2174 | } |
2175 | } |
2176 | put_buf(r1_bio); |
2177 | md_done_sync(conf->mddev, s, 1); |
2178 | } |
2179 | |
2180 | static void handle_write_finished(struct r1conf *conf, struct r1bio *r1_bio) |
2181 | { |
2182 | int m; |
2183 | for (m = 0; m < conf->raid_disks * 2 ; m++) |
2184 | if (r1_bio->bios[m] == IO_MADE_GOOD) { |
2185 | struct md_rdev *rdev = conf->mirrors[m].rdev; |
2186 | rdev_clear_badblocks(rdev, |
2187 | r1_bio->sector, |
2188 | r1_bio->sectors, 0); |
2189 | rdev_dec_pending(rdev, conf->mddev); |
2190 | } else if (r1_bio->bios[m] != NULL) { |
2191 | /* This drive got a write error. We need to |
2192 | * narrow down and record precise write |
2193 | * errors. |
2194 | */ |
2195 | if (!narrow_write_error(r1_bio, m)) { |
2196 | md_error(conf->mddev, |
2197 | conf->mirrors[m].rdev); |
2198 | /* an I/O failed, we can't clear the bitmap */ |
2199 | set_bit(R1BIO_Degraded, &r1_bio->state); |
2200 | } |
2201 | rdev_dec_pending(conf->mirrors[m].rdev, |
2202 | conf->mddev); |
2203 | } |
2204 | if (test_bit(R1BIO_WriteError, &r1_bio->state)) |
2205 | close_write(r1_bio); |
2206 | raid_end_bio_io(r1_bio); |
2207 | } |
2208 | |
2209 | static void handle_read_error(struct r1conf *conf, struct r1bio *r1_bio) |
2210 | { |
2211 | int disk; |
2212 | int max_sectors; |
2213 | struct mddev *mddev = conf->mddev; |
2214 | struct bio *bio; |
2215 | char b[BDEVNAME_SIZE]; |
2216 | struct md_rdev *rdev; |
2217 | |
2218 | clear_bit(R1BIO_ReadError, &r1_bio->state); |
2219 | /* we got a read error. Maybe the drive is bad. Maybe just |
2220 | * the block and we can fix it. |
2221 | * We freeze all other IO, and try reading the block from |
2222 | * other devices. When we find one, we re-write |
2223 | * and check it that fixes the read error. |
2224 | * This is all done synchronously while the array is |
2225 | * frozen |
2226 | */ |
2227 | if (mddev->ro == 0) { |
2228 | freeze_array(conf); |
2229 | fix_read_error(conf, r1_bio->read_disk, |
2230 | r1_bio->sector, r1_bio->sectors); |
2231 | unfreeze_array(conf); |
2232 | } else |
2233 | md_error(mddev, conf->mirrors[r1_bio->read_disk].rdev); |
2234 | rdev_dec_pending(conf->mirrors[r1_bio->read_disk].rdev, conf->mddev); |
2235 | |
2236 | bio = r1_bio->bios[r1_bio->read_disk]; |
2237 | bdevname(bio->bi_bdev, b); |
2238 | read_more: |
2239 | disk = read_balance(conf, r1_bio, &max_sectors); |
2240 | if (disk == -1) { |
2241 | printk(KERN_ALERT "md/raid1:%s: %s: unrecoverable I/O" |
2242 | " read error for block %llu\n", |
2243 | mdname(mddev), b, (unsigned long long)r1_bio->sector); |
2244 | raid_end_bio_io(r1_bio); |
2245 | } else { |
2246 | const unsigned long do_sync |
2247 | = r1_bio->master_bio->bi_rw & REQ_SYNC; |
2248 | if (bio) { |
2249 | r1_bio->bios[r1_bio->read_disk] = |
2250 | mddev->ro ? IO_BLOCKED : NULL; |
2251 | bio_put(bio); |
2252 | } |
2253 | r1_bio->read_disk = disk; |
2254 | bio = bio_clone_mddev(r1_bio->master_bio, GFP_NOIO, mddev); |
2255 | md_trim_bio(bio, r1_bio->sector - bio->bi_sector, max_sectors); |
2256 | r1_bio->bios[r1_bio->read_disk] = bio; |
2257 | rdev = conf->mirrors[disk].rdev; |
2258 | printk_ratelimited(KERN_ERR |
2259 | "md/raid1:%s: redirecting sector %llu" |
2260 | " to other mirror: %s\n", |
2261 | mdname(mddev), |
2262 | (unsigned long long)r1_bio->sector, |
2263 | bdevname(rdev->bdev, b)); |
2264 | bio->bi_sector = r1_bio->sector + rdev->data_offset; |
2265 | bio->bi_bdev = rdev->bdev; |
2266 | bio->bi_end_io = raid1_end_read_request; |
2267 | bio->bi_rw = READ | do_sync; |
2268 | bio->bi_private = r1_bio; |
2269 | if (max_sectors < r1_bio->sectors) { |
2270 | /* Drat - have to split this up more */ |
2271 | struct bio *mbio = r1_bio->master_bio; |
2272 | int sectors_handled = (r1_bio->sector + max_sectors |
2273 | - mbio->bi_sector); |
2274 | r1_bio->sectors = max_sectors; |
2275 | spin_lock_irq(&conf->device_lock); |
2276 | if (mbio->bi_phys_segments == 0) |
2277 | mbio->bi_phys_segments = 2; |
2278 | else |
2279 | mbio->bi_phys_segments++; |
2280 | spin_unlock_irq(&conf->device_lock); |
2281 | generic_make_request(bio); |
2282 | bio = NULL; |
2283 | |
2284 | r1_bio = mempool_alloc(conf->r1bio_pool, GFP_NOIO); |
2285 | |
2286 | r1_bio->master_bio = mbio; |
2287 | r1_bio->sectors = (mbio->bi_size >> 9) |
2288 | - sectors_handled; |
2289 | r1_bio->state = 0; |
2290 | set_bit(R1BIO_ReadError, &r1_bio->state); |
2291 | r1_bio->mddev = mddev; |
2292 | r1_bio->sector = mbio->bi_sector + sectors_handled; |
2293 | |
2294 | goto read_more; |
2295 | } else |
2296 | generic_make_request(bio); |
2297 | } |
2298 | } |
2299 | |
2300 | static void raid1d(struct md_thread *thread) |
2301 | { |
2302 | struct mddev *mddev = thread->mddev; |
2303 | struct r1bio *r1_bio; |
2304 | unsigned long flags; |
2305 | struct r1conf *conf = mddev->private; |
2306 | struct list_head *head = &conf->retry_list; |
2307 | struct blk_plug plug; |
2308 | |
2309 | md_check_recovery(mddev); |
2310 | |
2311 | blk_start_plug(&plug); |
2312 | for (;;) { |
2313 | |
2314 | flush_pending_writes(conf); |
2315 | |
2316 | spin_lock_irqsave(&conf->device_lock, flags); |
2317 | if (list_empty(head)) { |
2318 | spin_unlock_irqrestore(&conf->device_lock, flags); |
2319 | break; |
2320 | } |
2321 | r1_bio = list_entry(head->prev, struct r1bio, retry_list); |
2322 | list_del(head->prev); |
2323 | conf->nr_queued--; |
2324 | spin_unlock_irqrestore(&conf->device_lock, flags); |
2325 | |
2326 | mddev = r1_bio->mddev; |
2327 | conf = mddev->private; |
2328 | if (test_bit(R1BIO_IsSync, &r1_bio->state)) { |
2329 | if (test_bit(R1BIO_MadeGood, &r1_bio->state) || |
2330 | test_bit(R1BIO_WriteError, &r1_bio->state)) |
2331 | handle_sync_write_finished(conf, r1_bio); |
2332 | else |
2333 | sync_request_write(mddev, r1_bio); |
2334 | } else if (test_bit(R1BIO_MadeGood, &r1_bio->state) || |
2335 | test_bit(R1BIO_WriteError, &r1_bio->state)) |
2336 | handle_write_finished(conf, r1_bio); |
2337 | else if (test_bit(R1BIO_ReadError, &r1_bio->state)) |
2338 | handle_read_error(conf, r1_bio); |
2339 | else |
2340 | /* just a partial read to be scheduled from separate |
2341 | * context |
2342 | */ |
2343 | generic_make_request(r1_bio->bios[r1_bio->read_disk]); |
2344 | |
2345 | cond_resched(); |
2346 | if (mddev->flags & ~(1<<MD_CHANGE_PENDING)) |
2347 | md_check_recovery(mddev); |
2348 | } |
2349 | blk_finish_plug(&plug); |
2350 | } |
2351 | |
2352 | |
2353 | static int init_resync(struct r1conf *conf) |
2354 | { |
2355 | int buffs; |
2356 | |
2357 | buffs = RESYNC_WINDOW / RESYNC_BLOCK_SIZE; |
2358 | BUG_ON(conf->r1buf_pool); |
2359 | conf->r1buf_pool = mempool_create(buffs, r1buf_pool_alloc, r1buf_pool_free, |
2360 | conf->poolinfo); |
2361 | if (!conf->r1buf_pool) |
2362 | return -ENOMEM; |
2363 | conf->next_resync = 0; |
2364 | return 0; |
2365 | } |
2366 | |
2367 | /* |
2368 | * perform a "sync" on one "block" |
2369 | * |
2370 | * We need to make sure that no normal I/O request - particularly write |
2371 | * requests - conflict with active sync requests. |
2372 | * |
2373 | * This is achieved by tracking pending requests and a 'barrier' concept |
2374 | * that can be installed to exclude normal IO requests. |
2375 | */ |
2376 | |
2377 | static sector_t sync_request(struct mddev *mddev, sector_t sector_nr, int *skipped, int go_faster) |
2378 | { |
2379 | struct r1conf *conf = mddev->private; |
2380 | struct r1bio *r1_bio; |
2381 | struct bio *bio; |
2382 | sector_t max_sector, nr_sectors; |
2383 | int disk = -1; |
2384 | int i; |
2385 | int wonly = -1; |
2386 | int write_targets = 0, read_targets = 0; |
2387 | sector_t sync_blocks; |
2388 | int still_degraded = 0; |
2389 | int good_sectors = RESYNC_SECTORS; |
2390 | int min_bad = 0; /* number of sectors that are bad in all devices */ |
2391 | |
2392 | if (!conf->r1buf_pool) |
2393 | if (init_resync(conf)) |
2394 | return 0; |
2395 | |
2396 | max_sector = mddev->dev_sectors; |
2397 | if (sector_nr >= max_sector) { |
2398 | /* If we aborted, we need to abort the |
2399 | * sync on the 'current' bitmap chunk (there will |
2400 | * only be one in raid1 resync. |
2401 | * We can find the current addess in mddev->curr_resync |
2402 | */ |
2403 | if (mddev->curr_resync < max_sector) /* aborted */ |
2404 | bitmap_end_sync(mddev->bitmap, mddev->curr_resync, |
2405 | &sync_blocks, 1); |
2406 | else /* completed sync */ |
2407 | conf->fullsync = 0; |
2408 | |
2409 | bitmap_close_sync(mddev->bitmap); |
2410 | close_sync(conf); |
2411 | return 0; |
2412 | } |
2413 | |
2414 | if (mddev->bitmap == NULL && |
2415 | mddev->recovery_cp == MaxSector && |
2416 | !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) && |
2417 | conf->fullsync == 0) { |
2418 | *skipped = 1; |
2419 | return max_sector - sector_nr; |
2420 | } |
2421 | /* before building a request, check if we can skip these blocks.. |
2422 | * This call the bitmap_start_sync doesn't actually record anything |
2423 | */ |
2424 | if (!bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) && |
2425 | !conf->fullsync && !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) { |
2426 | /* We can skip this block, and probably several more */ |
2427 | *skipped = 1; |
2428 | return sync_blocks; |
2429 | } |
2430 | /* |
2431 | * If there is non-resync activity waiting for a turn, |
2432 | * and resync is going fast enough, |
2433 | * then let it though before starting on this new sync request. |
2434 | */ |
2435 | if (!go_faster && conf->nr_waiting) |
2436 | msleep_interruptible(1000); |
2437 | |
2438 | bitmap_cond_end_sync(mddev->bitmap, sector_nr); |
2439 | r1_bio = mempool_alloc(conf->r1buf_pool, GFP_NOIO); |
2440 | raise_barrier(conf); |
2441 | |
2442 | conf->next_resync = sector_nr; |
2443 | |
2444 | rcu_read_lock(); |
2445 | /* |
2446 | * If we get a correctably read error during resync or recovery, |
2447 | * we might want to read from a different device. So we |
2448 | * flag all drives that could conceivably be read from for READ, |
2449 | * and any others (which will be non-In_sync devices) for WRITE. |
2450 | * If a read fails, we try reading from something else for which READ |
2451 | * is OK. |
2452 | */ |
2453 | |
2454 | r1_bio->mddev = mddev; |
2455 | r1_bio->sector = sector_nr; |
2456 | r1_bio->state = 0; |
2457 | set_bit(R1BIO_IsSync, &r1_bio->state); |
2458 | |
2459 | for (i = 0; i < conf->raid_disks * 2; i++) { |
2460 | struct md_rdev *rdev; |
2461 | bio = r1_bio->bios[i]; |
2462 | |
2463 | /* take from bio_init */ |
2464 | bio->bi_next = NULL; |
2465 | bio->bi_flags &= ~(BIO_POOL_MASK-1); |
2466 | bio->bi_flags |= 1 << BIO_UPTODATE; |
2467 | bio->bi_rw = READ; |
2468 | bio->bi_vcnt = 0; |
2469 | bio->bi_idx = 0; |
2470 | bio->bi_phys_segments = 0; |
2471 | bio->bi_size = 0; |
2472 | bio->bi_end_io = NULL; |
2473 | bio->bi_private = NULL; |
2474 | |
2475 | rdev = rcu_dereference(conf->mirrors[i].rdev); |
2476 | if (rdev == NULL || |
2477 | test_bit(Faulty, &rdev->flags)) { |
2478 | if (i < conf->raid_disks) |
2479 | still_degraded = 1; |
2480 | } else if (!test_bit(In_sync, &rdev->flags)) { |
2481 | bio->bi_rw = WRITE; |
2482 | bio->bi_end_io = end_sync_write; |
2483 | write_targets ++; |
2484 | } else { |
2485 | /* may need to read from here */ |
2486 | sector_t first_bad = MaxSector; |
2487 | int bad_sectors; |
2488 | |
2489 | if (is_badblock(rdev, sector_nr, good_sectors, |
2490 | &first_bad, &bad_sectors)) { |
2491 | if (first_bad > sector_nr) |
2492 | good_sectors = first_bad - sector_nr; |
2493 | else { |
2494 | bad_sectors -= (sector_nr - first_bad); |
2495 | if (min_bad == 0 || |
2496 | min_bad > bad_sectors) |
2497 | min_bad = bad_sectors; |
2498 | } |
2499 | } |
2500 | if (sector_nr < first_bad) { |
2501 | if (test_bit(WriteMostly, &rdev->flags)) { |
2502 | if (wonly < 0) |
2503 | wonly = i; |
2504 | } else { |
2505 | if (disk < 0) |
2506 | disk = i; |
2507 | } |
2508 | bio->bi_rw = READ; |
2509 | bio->bi_end_io = end_sync_read; |
2510 | read_targets++; |
2511 | } else if (!test_bit(WriteErrorSeen, &rdev->flags) && |
2512 | test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && |
2513 | !test_bit(MD_RECOVERY_CHECK, &mddev->recovery)) { |
2514 | /* |
2515 | * The device is suitable for reading (InSync), |
2516 | * but has bad block(s) here. Let's try to correct them, |
2517 | * if we are doing resync or repair. Otherwise, leave |
2518 | * this device alone for this sync request. |
2519 | */ |
2520 | bio->bi_rw = WRITE; |
2521 | bio->bi_end_io = end_sync_write; |
2522 | write_targets++; |
2523 | } |
2524 | } |
2525 | if (bio->bi_end_io) { |
2526 | atomic_inc(&rdev->nr_pending); |
2527 | bio->bi_sector = sector_nr + rdev->data_offset; |
2528 | bio->bi_bdev = rdev->bdev; |
2529 | bio->bi_private = r1_bio; |
2530 | } |
2531 | } |
2532 | rcu_read_unlock(); |
2533 | if (disk < 0) |
2534 | disk = wonly; |
2535 | r1_bio->read_disk = disk; |
2536 | |
2537 | if (read_targets == 0 && min_bad > 0) { |
2538 | /* These sectors are bad on all InSync devices, so we |
2539 | * need to mark them bad on all write targets |
2540 | */ |
2541 | int ok = 1; |
2542 | for (i = 0 ; i < conf->raid_disks * 2 ; i++) |
2543 | if (r1_bio->bios[i]->bi_end_io == end_sync_write) { |
2544 | struct md_rdev *rdev = conf->mirrors[i].rdev; |
2545 | ok = rdev_set_badblocks(rdev, sector_nr, |
2546 | min_bad, 0 |
2547 | ) && ok; |
2548 | } |
2549 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
2550 | *skipped = 1; |
2551 | put_buf(r1_bio); |
2552 | |
2553 | if (!ok) { |
2554 | /* Cannot record the badblocks, so need to |
2555 | * abort the resync. |
2556 | * If there are multiple read targets, could just |
2557 | * fail the really bad ones ??? |
2558 | */ |
2559 | conf->recovery_disabled = mddev->recovery_disabled; |
2560 | set_bit(MD_RECOVERY_INTR, &mddev->recovery); |
2561 | return 0; |
2562 | } else |
2563 | return min_bad; |
2564 | |
2565 | } |
2566 | if (min_bad > 0 && min_bad < good_sectors) { |
2567 | /* only resync enough to reach the next bad->good |
2568 | * transition */ |
2569 | good_sectors = min_bad; |
2570 | } |
2571 | |
2572 | if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && read_targets > 0) |
2573 | /* extra read targets are also write targets */ |
2574 | write_targets += read_targets-1; |
2575 | |
2576 | if (write_targets == 0 || read_targets == 0) { |
2577 | /* There is nowhere to write, so all non-sync |
2578 | * drives must be failed - so we are finished |
2579 | */ |
2580 | sector_t rv; |
2581 | if (min_bad > 0) |
2582 | max_sector = sector_nr + min_bad; |
2583 | rv = max_sector - sector_nr; |
2584 | *skipped = 1; |
2585 | put_buf(r1_bio); |
2586 | return rv; |
2587 | } |
2588 | |
2589 | if (max_sector > mddev->resync_max) |
2590 | max_sector = mddev->resync_max; /* Don't do IO beyond here */ |
2591 | if (max_sector > sector_nr + good_sectors) |
2592 | max_sector = sector_nr + good_sectors; |
2593 | nr_sectors = 0; |
2594 | sync_blocks = 0; |
2595 | do { |
2596 | struct page *page; |
2597 | int len = PAGE_SIZE; |
2598 | if (sector_nr + (len>>9) > max_sector) |
2599 | len = (max_sector - sector_nr) << 9; |
2600 | if (len == 0) |
2601 | break; |
2602 | if (sync_blocks == 0) { |
2603 | if (!bitmap_start_sync(mddev->bitmap, sector_nr, |
2604 | &sync_blocks, still_degraded) && |
2605 | !conf->fullsync && |
2606 | !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) |
2607 | break; |
2608 | BUG_ON(sync_blocks < (PAGE_SIZE>>9)); |
2609 | if ((len >> 9) > sync_blocks) |
2610 | len = sync_blocks<<9; |
2611 | } |
2612 | |
2613 | for (i = 0 ; i < conf->raid_disks * 2; i++) { |
2614 | bio = r1_bio->bios[i]; |
2615 | if (bio->bi_end_io) { |
2616 | page = bio->bi_io_vec[bio->bi_vcnt].bv_page; |
2617 | if (bio_add_page(bio, page, len, 0) == 0) { |
2618 | /* stop here */ |
2619 | bio->bi_io_vec[bio->bi_vcnt].bv_page = page; |
2620 | while (i > 0) { |
2621 | i--; |
2622 | bio = r1_bio->bios[i]; |
2623 | if (bio->bi_end_io==NULL) |
2624 | continue; |
2625 | /* remove last page from this bio */ |
2626 | bio->bi_vcnt--; |
2627 | bio->bi_size -= len; |
2628 | bio->bi_flags &= ~(1<< BIO_SEG_VALID); |
2629 | } |
2630 | goto bio_full; |
2631 | } |
2632 | } |
2633 | } |
2634 | nr_sectors += len>>9; |
2635 | sector_nr += len>>9; |
2636 | sync_blocks -= (len>>9); |
2637 | } while (r1_bio->bios[disk]->bi_vcnt < RESYNC_PAGES); |
2638 | bio_full: |
2639 | r1_bio->sectors = nr_sectors; |
2640 | |
2641 | /* For a user-requested sync, we read all readable devices and do a |
2642 | * compare |
2643 | */ |
2644 | if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) { |
2645 | atomic_set(&r1_bio->remaining, read_targets); |
2646 | for (i = 0; i < conf->raid_disks * 2 && read_targets; i++) { |
2647 | bio = r1_bio->bios[i]; |
2648 | if (bio->bi_end_io == end_sync_read) { |
2649 | read_targets--; |
2650 | md_sync_acct(bio->bi_bdev, nr_sectors); |
2651 | generic_make_request(bio); |
2652 | } |
2653 | } |
2654 | } else { |
2655 | atomic_set(&r1_bio->remaining, 1); |
2656 | bio = r1_bio->bios[r1_bio->read_disk]; |
2657 | md_sync_acct(bio->bi_bdev, nr_sectors); |
2658 | generic_make_request(bio); |
2659 | |
2660 | } |
2661 | return nr_sectors; |
2662 | } |
2663 | |
2664 | static sector_t raid1_size(struct mddev *mddev, sector_t sectors, int raid_disks) |
2665 | { |
2666 | if (sectors) |
2667 | return sectors; |
2668 | |
2669 | return mddev->dev_sectors; |
2670 | } |
2671 | |
2672 | static struct r1conf *setup_conf(struct mddev *mddev) |
2673 | { |
2674 | struct r1conf *conf; |
2675 | int i; |
2676 | struct raid1_info *disk; |
2677 | struct md_rdev *rdev; |
2678 | int err = -ENOMEM; |
2679 | |
2680 | conf = kzalloc(sizeof(struct r1conf), GFP_KERNEL); |
2681 | if (!conf) |
2682 | goto abort; |
2683 | |
2684 | conf->mirrors = kzalloc(sizeof(struct raid1_info) |
2685 | * mddev->raid_disks * 2, |
2686 | GFP_KERNEL); |
2687 | if (!conf->mirrors) |
2688 | goto abort; |
2689 | |
2690 | conf->tmppage = alloc_page(GFP_KERNEL); |
2691 | if (!conf->tmppage) |
2692 | goto abort; |
2693 | |
2694 | conf->poolinfo = kzalloc(sizeof(*conf->poolinfo), GFP_KERNEL); |
2695 | if (!conf->poolinfo) |
2696 | goto abort; |
2697 | conf->poolinfo->raid_disks = mddev->raid_disks * 2; |
2698 | conf->r1bio_pool = mempool_create(NR_RAID1_BIOS, r1bio_pool_alloc, |
2699 | r1bio_pool_free, |
2700 | conf->poolinfo); |
2701 | if (!conf->r1bio_pool) |
2702 | goto abort; |
2703 | |
2704 | conf->poolinfo->mddev = mddev; |
2705 | |
2706 | err = -EINVAL; |
2707 | spin_lock_init(&conf->device_lock); |
2708 | rdev_for_each(rdev, mddev) { |
2709 | struct request_queue *q; |
2710 | int disk_idx = rdev->raid_disk; |
2711 | if (disk_idx >= mddev->raid_disks |
2712 | || disk_idx < 0) |
2713 | continue; |
2714 | if (test_bit(Replacement, &rdev->flags)) |
2715 | disk = conf->mirrors + mddev->raid_disks + disk_idx; |
2716 | else |
2717 | disk = conf->mirrors + disk_idx; |
2718 | |
2719 | if (disk->rdev) |
2720 | goto abort; |
2721 | disk->rdev = rdev; |
2722 | q = bdev_get_queue(rdev->bdev); |
2723 | if (q->merge_bvec_fn) |
2724 | mddev->merge_check_needed = 1; |
2725 | |
2726 | disk->head_position = 0; |
2727 | disk->seq_start = MaxSector; |
2728 | } |
2729 | conf->raid_disks = mddev->raid_disks; |
2730 | conf->mddev = mddev; |
2731 | INIT_LIST_HEAD(&conf->retry_list); |
2732 | |
2733 | spin_lock_init(&conf->resync_lock); |
2734 | init_waitqueue_head(&conf->wait_barrier); |
2735 | |
2736 | bio_list_init(&conf->pending_bio_list); |
2737 | conf->pending_count = 0; |
2738 | conf->recovery_disabled = mddev->recovery_disabled - 1; |
2739 | |
2740 | err = -EIO; |
2741 | for (i = 0; i < conf->raid_disks * 2; i++) { |
2742 | |
2743 | disk = conf->mirrors + i; |
2744 | |
2745 | if (i < conf->raid_disks && |
2746 | disk[conf->raid_disks].rdev) { |
2747 | /* This slot has a replacement. */ |
2748 | if (!disk->rdev) { |
2749 | /* No original, just make the replacement |
2750 | * a recovering spare |
2751 | */ |
2752 | disk->rdev = |
2753 | disk[conf->raid_disks].rdev; |
2754 | disk[conf->raid_disks].rdev = NULL; |
2755 | } else if (!test_bit(In_sync, &disk->rdev->flags)) |
2756 | /* Original is not in_sync - bad */ |
2757 | goto abort; |
2758 | } |
2759 | |
2760 | if (!disk->rdev || |
2761 | !test_bit(In_sync, &disk->rdev->flags)) { |
2762 | disk->head_position = 0; |
2763 | if (disk->rdev && |
2764 | (disk->rdev->saved_raid_disk < 0)) |
2765 | conf->fullsync = 1; |
2766 | } |
2767 | } |
2768 | |
2769 | err = -ENOMEM; |
2770 | conf->thread = md_register_thread(raid1d, mddev, "raid1"); |
2771 | if (!conf->thread) { |
2772 | printk(KERN_ERR |
2773 | "md/raid1:%s: couldn't allocate thread\n", |
2774 | mdname(mddev)); |
2775 | goto abort; |
2776 | } |
2777 | |
2778 | return conf; |
2779 | |
2780 | abort: |
2781 | if (conf) { |
2782 | if (conf->r1bio_pool) |
2783 | mempool_destroy(conf->r1bio_pool); |
2784 | kfree(conf->mirrors); |
2785 | safe_put_page(conf->tmppage); |
2786 | kfree(conf->poolinfo); |
2787 | kfree(conf); |
2788 | } |
2789 | return ERR_PTR(err); |
2790 | } |
2791 | |
2792 | static int stop(struct mddev *mddev); |
2793 | static int run(struct mddev *mddev) |
2794 | { |
2795 | struct r1conf *conf; |
2796 | int i; |
2797 | struct md_rdev *rdev; |
2798 | int ret; |
2799 | bool discard_supported = false; |
2800 | |
2801 | if (mddev->level != 1) { |
2802 | printk(KERN_ERR "md/raid1:%s: raid level not set to mirroring (%d)\n", |
2803 | mdname(mddev), mddev->level); |
2804 | return -EIO; |
2805 | } |
2806 | if (mddev->reshape_position != MaxSector) { |
2807 | printk(KERN_ERR "md/raid1:%s: reshape_position set but not supported\n", |
2808 | mdname(mddev)); |
2809 | return -EIO; |
2810 | } |
2811 | /* |
2812 | * copy the already verified devices into our private RAID1 |
2813 | * bookkeeping area. [whatever we allocate in run(), |
2814 | * should be freed in stop()] |
2815 | */ |
2816 | if (mddev->private == NULL) |
2817 | conf = setup_conf(mddev); |
2818 | else |
2819 | conf = mddev->private; |
2820 | |
2821 | if (IS_ERR(conf)) |
2822 | return PTR_ERR(conf); |
2823 | |
2824 | if (mddev->queue) |
2825 | blk_queue_max_write_same_sectors(mddev->queue, |
2826 | mddev->chunk_sectors); |
2827 | rdev_for_each(rdev, mddev) { |
2828 | if (!mddev->gendisk) |
2829 | continue; |
2830 | disk_stack_limits(mddev->gendisk, rdev->bdev, |
2831 | rdev->data_offset << 9); |
2832 | if (blk_queue_discard(bdev_get_queue(rdev->bdev))) |
2833 | discard_supported = true; |
2834 | } |
2835 | |
2836 | mddev->degraded = 0; |
2837 | for (i=0; i < conf->raid_disks; i++) |
2838 | if (conf->mirrors[i].rdev == NULL || |
2839 | !test_bit(In_sync, &conf->mirrors[i].rdev->flags) || |
2840 | test_bit(Faulty, &conf->mirrors[i].rdev->flags)) |
2841 | mddev->degraded++; |
2842 | |
2843 | if (conf->raid_disks - mddev->degraded == 1) |
2844 | mddev->recovery_cp = MaxSector; |
2845 | |
2846 | if (mddev->recovery_cp != MaxSector) |
2847 | printk(KERN_NOTICE "md/raid1:%s: not clean" |
2848 | " -- starting background reconstruction\n", |
2849 | mdname(mddev)); |
2850 | printk(KERN_INFO |
2851 | "md/raid1:%s: active with %d out of %d mirrors\n", |
2852 | mdname(mddev), mddev->raid_disks - mddev->degraded, |
2853 | mddev->raid_disks); |
2854 | |
2855 | /* |
2856 | * Ok, everything is just fine now |
2857 | */ |
2858 | mddev->thread = conf->thread; |
2859 | conf->thread = NULL; |
2860 | mddev->private = conf; |
2861 | |
2862 | md_set_array_sectors(mddev, raid1_size(mddev, 0, 0)); |
2863 | |
2864 | if (mddev->queue) { |
2865 | mddev->queue->backing_dev_info.congested_fn = raid1_congested; |
2866 | mddev->queue->backing_dev_info.congested_data = mddev; |
2867 | blk_queue_merge_bvec(mddev->queue, raid1_mergeable_bvec); |
2868 | |
2869 | if (discard_supported) |
2870 | queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, |
2871 | mddev->queue); |
2872 | else |
2873 | queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, |
2874 | mddev->queue); |
2875 | } |
2876 | |
2877 | ret = md_integrity_register(mddev); |
2878 | if (ret) |
2879 | stop(mddev); |
2880 | return ret; |
2881 | } |
2882 | |
2883 | static int stop(struct mddev *mddev) |
2884 | { |
2885 | struct r1conf *conf = mddev->private; |
2886 | struct bitmap *bitmap = mddev->bitmap; |
2887 | |
2888 | /* wait for behind writes to complete */ |
2889 | if (bitmap && atomic_read(&bitmap->behind_writes) > 0) { |
2890 | printk(KERN_INFO "md/raid1:%s: behind writes in progress - waiting to stop.\n", |
2891 | mdname(mddev)); |
2892 | /* need to kick something here to make sure I/O goes? */ |
2893 | wait_event(bitmap->behind_wait, |
2894 | atomic_read(&bitmap->behind_writes) == 0); |
2895 | } |
2896 | |
2897 | raise_barrier(conf); |
2898 | lower_barrier(conf); |
2899 | |
2900 | md_unregister_thread(&mddev->thread); |
2901 | if (conf->r1bio_pool) |
2902 | mempool_destroy(conf->r1bio_pool); |
2903 | kfree(conf->mirrors); |
2904 | kfree(conf->poolinfo); |
2905 | kfree(conf); |
2906 | mddev->private = NULL; |
2907 | return 0; |
2908 | } |
2909 | |
2910 | static int raid1_resize(struct mddev *mddev, sector_t sectors) |
2911 | { |
2912 | /* no resync is happening, and there is enough space |
2913 | * on all devices, so we can resize. |
2914 | * We need to make sure resync covers any new space. |
2915 | * If the array is shrinking we should possibly wait until |
2916 | * any io in the removed space completes, but it hardly seems |
2917 | * worth it. |
2918 | */ |
2919 | sector_t newsize = raid1_size(mddev, sectors, 0); |
2920 | if (mddev->external_size && |
2921 | mddev->array_sectors > newsize) |
2922 | return -EINVAL; |
2923 | if (mddev->bitmap) { |
2924 | int ret = bitmap_resize(mddev->bitmap, newsize, 0, 0); |
2925 | if (ret) |
2926 | return ret; |
2927 | } |
2928 | md_set_array_sectors(mddev, newsize); |
2929 | set_capacity(mddev->gendisk, mddev->array_sectors); |
2930 | revalidate_disk(mddev->gendisk); |
2931 | if (sectors > mddev->dev_sectors && |
2932 | mddev->recovery_cp > mddev->dev_sectors) { |
2933 | mddev->recovery_cp = mddev->dev_sectors; |
2934 | set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); |
2935 | } |
2936 | mddev->dev_sectors = sectors; |
2937 | mddev->resync_max_sectors = sectors; |
2938 | return 0; |
2939 | } |
2940 | |
2941 | static int raid1_reshape(struct mddev *mddev) |
2942 | { |
2943 | /* We need to: |
2944 | * 1/ resize the r1bio_pool |
2945 | * 2/ resize conf->mirrors |
2946 | * |
2947 | * We allocate a new r1bio_pool if we can. |
2948 | * Then raise a device barrier and wait until all IO stops. |
2949 | * Then resize conf->mirrors and swap in the new r1bio pool. |
2950 | * |
2951 | * At the same time, we "pack" the devices so that all the missing |
2952 | * devices have the higher raid_disk numbers. |
2953 | */ |
2954 | mempool_t *newpool, *oldpool; |
2955 | struct pool_info *newpoolinfo; |
2956 | struct raid1_info *newmirrors; |
2957 | struct r1conf *conf = mddev->private; |
2958 | int cnt, raid_disks; |
2959 | unsigned long flags; |
2960 | int d, d2, err; |
2961 | |
2962 | /* Cannot change chunk_size, layout, or level */ |
2963 | if (mddev->chunk_sectors != mddev->new_chunk_sectors || |
2964 | mddev->layout != mddev->new_layout || |
2965 | mddev->level != mddev->new_level) { |
2966 | mddev->new_chunk_sectors = mddev->chunk_sectors; |
2967 | mddev->new_layout = mddev->layout; |
2968 | mddev->new_level = mddev->level; |
2969 | return -EINVAL; |
2970 | } |
2971 | |
2972 | err = md_allow_write(mddev); |
2973 | if (err) |
2974 | return err; |
2975 | |
2976 | raid_disks = mddev->raid_disks + mddev->delta_disks; |
2977 | |
2978 | if (raid_disks < conf->raid_disks) { |
2979 | cnt=0; |
2980 | for (d= 0; d < conf->raid_disks; d++) |
2981 | if (conf->mirrors[d].rdev) |
2982 | cnt++; |
2983 | if (cnt > raid_disks) |
2984 | return -EBUSY; |
2985 | } |
2986 | |
2987 | newpoolinfo = kmalloc(sizeof(*newpoolinfo), GFP_KERNEL); |
2988 | if (!newpoolinfo) |
2989 | return -ENOMEM; |
2990 | newpoolinfo->mddev = mddev; |
2991 | newpoolinfo->raid_disks = raid_disks * 2; |
2992 | |
2993 | newpool = mempool_create(NR_RAID1_BIOS, r1bio_pool_alloc, |
2994 | r1bio_pool_free, newpoolinfo); |
2995 | if (!newpool) { |
2996 | kfree(newpoolinfo); |
2997 | return -ENOMEM; |
2998 | } |
2999 | newmirrors = kzalloc(sizeof(struct raid1_info) * raid_disks * 2, |
3000 | GFP_KERNEL); |
3001 | if (!newmirrors) { |
3002 | kfree(newpoolinfo); |
3003 | mempool_destroy(newpool); |
3004 | return -ENOMEM; |
3005 | } |
3006 | |
3007 | raise_barrier(conf); |
3008 | |
3009 | /* ok, everything is stopped */ |
3010 | oldpool = conf->r1bio_pool; |
3011 | conf->r1bio_pool = newpool; |
3012 | |
3013 | for (d = d2 = 0; d < conf->raid_disks; d++) { |
3014 | struct md_rdev *rdev = conf->mirrors[d].rdev; |
3015 | if (rdev && rdev->raid_disk != d2) { |
3016 | sysfs_unlink_rdev(mddev, rdev); |
3017 | rdev->raid_disk = d2; |
3018 | sysfs_unlink_rdev(mddev, rdev); |
3019 | if (sysfs_link_rdev(mddev, rdev)) |
3020 | printk(KERN_WARNING |
3021 | "md/raid1:%s: cannot register rd%d\n", |
3022 | mdname(mddev), rdev->raid_disk); |
3023 | } |
3024 | if (rdev) |
3025 | newmirrors[d2++].rdev = rdev; |
3026 | } |
3027 | kfree(conf->mirrors); |
3028 | conf->mirrors = newmirrors; |
3029 | kfree(conf->poolinfo); |
3030 | conf->poolinfo = newpoolinfo; |
3031 | |
3032 | spin_lock_irqsave(&conf->device_lock, flags); |
3033 | mddev->degraded += (raid_disks - conf->raid_disks); |
3034 | spin_unlock_irqrestore(&conf->device_lock, flags); |
3035 | conf->raid_disks = mddev->raid_disks = raid_disks; |
3036 | mddev->delta_disks = 0; |
3037 | |
3038 | lower_barrier(conf); |
3039 | |
3040 | set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); |
3041 | md_wakeup_thread(mddev->thread); |
3042 | |
3043 | mempool_destroy(oldpool); |
3044 | return 0; |
3045 | } |
3046 | |
3047 | static void raid1_quiesce(struct mddev *mddev, int state) |
3048 | { |
3049 | struct r1conf *conf = mddev->private; |
3050 | |
3051 | switch(state) { |
3052 | case 2: /* wake for suspend */ |
3053 | wake_up(&conf->wait_barrier); |
3054 | break; |
3055 | case 1: |
3056 | raise_barrier(conf); |
3057 | break; |
3058 | case 0: |
3059 | lower_barrier(conf); |
3060 | break; |
3061 | } |
3062 | } |
3063 | |
3064 | static void *raid1_takeover(struct mddev *mddev) |
3065 | { |
3066 | /* raid1 can take over: |
3067 | * raid5 with 2 devices, any layout or chunk size |
3068 | */ |
3069 | if (mddev->level == 5 && mddev->raid_disks == 2) { |
3070 | struct r1conf *conf; |
3071 | mddev->new_level = 1; |
3072 | mddev->new_layout = 0; |
3073 | mddev->new_chunk_sectors = 0; |
3074 | conf = setup_conf(mddev); |
3075 | if (!IS_ERR(conf)) |
3076 | conf->barrier = 1; |
3077 | return conf; |
3078 | } |
3079 | return ERR_PTR(-EINVAL); |
3080 | } |
3081 | |
3082 | static struct md_personality raid1_personality = |
3083 | { |
3084 | .name = "raid1", |
3085 | .level = 1, |
3086 | .owner = THIS_MODULE, |
3087 | .make_request = make_request, |
3088 | .run = run, |
3089 | .stop = stop, |
3090 | .status = status, |
3091 | .error_handler = error, |
3092 | .hot_add_disk = raid1_add_disk, |
3093 | .hot_remove_disk= raid1_remove_disk, |
3094 | .spare_active = raid1_spare_active, |
3095 | .sync_request = sync_request, |
3096 | .resize = raid1_resize, |
3097 | .size = raid1_size, |
3098 | .check_reshape = raid1_reshape, |
3099 | .quiesce = raid1_quiesce, |
3100 | .takeover = raid1_takeover, |
3101 | }; |
3102 | |
3103 | static int __init raid_init(void) |
3104 | { |
3105 | return register_md_personality(&raid1_personality); |
3106 | } |
3107 | |
3108 | static void raid_exit(void) |
3109 | { |
3110 | unregister_md_personality(&raid1_personality); |
3111 | } |
3112 | |
3113 | module_init(raid_init); |
3114 | module_exit(raid_exit); |
3115 | MODULE_LICENSE("GPL"); |
3116 | MODULE_DESCRIPTION("RAID1 (mirroring) personality for MD"); |
3117 | MODULE_ALIAS("md-personality-3"); /* RAID1 */ |
3118 | MODULE_ALIAS("md-raid1"); |
3119 | MODULE_ALIAS("md-level-1"); |
3120 | |
3121 | module_param(max_queued_requests, int, S_IRUGO|S_IWUSR); |
3122 |
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