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1da177e4 LT |
1 | /* |
2 | * raid10.c : Multiple Devices driver for Linux | |
3 | * | |
4 | * Copyright (C) 2000-2004 Neil Brown | |
5 | * | |
6 | * RAID-10 support for md. | |
7 | * | |
25985edc | 8 | * Base on code in raid1.c. See raid1.c for further copyright information. |
1da177e4 LT |
9 | * |
10 | * | |
11 | * This program is free software; you can redistribute it and/or modify | |
12 | * it under the terms of the GNU General Public License as published by | |
13 | * the Free Software Foundation; either version 2, or (at your option) | |
14 | * any later version. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * (for example /usr/src/linux/COPYING); if not, write to the Free | |
18 | * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
19 | */ | |
20 | ||
5a0e3ad6 | 21 | #include <linux/slab.h> |
25570727 | 22 | #include <linux/delay.h> |
bff61975 | 23 | #include <linux/blkdev.h> |
bff61975 | 24 | #include <linux/seq_file.h> |
43b2e5d8 | 25 | #include "md.h" |
ef740c37 | 26 | #include "raid10.h" |
dab8b292 | 27 | #include "raid0.h" |
ef740c37 | 28 | #include "bitmap.h" |
1da177e4 LT |
29 | |
30 | /* | |
31 | * RAID10 provides a combination of RAID0 and RAID1 functionality. | |
32 | * The layout of data is defined by | |
33 | * chunk_size | |
34 | * raid_disks | |
35 | * near_copies (stored in low byte of layout) | |
36 | * far_copies (stored in second byte of layout) | |
c93983bf | 37 | * far_offset (stored in bit 16 of layout ) |
1da177e4 LT |
38 | * |
39 | * The data to be stored is divided into chunks using chunksize. | |
40 | * Each device is divided into far_copies sections. | |
41 | * In each section, chunks are laid out in a style similar to raid0, but | |
42 | * near_copies copies of each chunk is stored (each on a different drive). | |
43 | * The starting device for each section is offset near_copies from the starting | |
44 | * device of the previous section. | |
c93983bf | 45 | * Thus they are (near_copies*far_copies) of each chunk, and each is on a different |
1da177e4 LT |
46 | * drive. |
47 | * near_copies and far_copies must be at least one, and their product is at most | |
48 | * raid_disks. | |
c93983bf N |
49 | * |
50 | * If far_offset is true, then the far_copies are handled a bit differently. | |
51 | * The copies are still in different stripes, but instead of be very far apart | |
52 | * on disk, there are adjacent stripes. | |
1da177e4 LT |
53 | */ |
54 | ||
55 | /* | |
56 | * Number of guaranteed r10bios in case of extreme VM load: | |
57 | */ | |
58 | #define NR_RAID10_BIOS 256 | |
59 | ||
0a27ec96 N |
60 | static void allow_barrier(conf_t *conf); |
61 | static void lower_barrier(conf_t *conf); | |
62 | ||
dd0fc66f | 63 | static void * r10bio_pool_alloc(gfp_t gfp_flags, void *data) |
1da177e4 LT |
64 | { |
65 | conf_t *conf = data; | |
1da177e4 LT |
66 | int size = offsetof(struct r10bio_s, devs[conf->copies]); |
67 | ||
68 | /* allocate a r10bio with room for raid_disks entries in the bios array */ | |
7eaceacc | 69 | return kzalloc(size, gfp_flags); |
1da177e4 LT |
70 | } |
71 | ||
72 | static void r10bio_pool_free(void *r10_bio, void *data) | |
73 | { | |
74 | kfree(r10_bio); | |
75 | } | |
76 | ||
0310fa21 | 77 | /* Maximum size of each resync request */ |
1da177e4 | 78 | #define RESYNC_BLOCK_SIZE (64*1024) |
1da177e4 | 79 | #define RESYNC_PAGES ((RESYNC_BLOCK_SIZE + PAGE_SIZE-1) / PAGE_SIZE) |
0310fa21 N |
80 | /* amount of memory to reserve for resync requests */ |
81 | #define RESYNC_WINDOW (1024*1024) | |
82 | /* maximum number of concurrent requests, memory permitting */ | |
83 | #define RESYNC_DEPTH (32*1024*1024/RESYNC_BLOCK_SIZE) | |
1da177e4 LT |
84 | |
85 | /* | |
86 | * When performing a resync, we need to read and compare, so | |
87 | * we need as many pages are there are copies. | |
88 | * When performing a recovery, we need 2 bios, one for read, | |
89 | * one for write (we recover only one drive per r10buf) | |
90 | * | |
91 | */ | |
dd0fc66f | 92 | static void * r10buf_pool_alloc(gfp_t gfp_flags, void *data) |
1da177e4 LT |
93 | { |
94 | conf_t *conf = data; | |
95 | struct page *page; | |
96 | r10bio_t *r10_bio; | |
97 | struct bio *bio; | |
98 | int i, j; | |
99 | int nalloc; | |
100 | ||
101 | r10_bio = r10bio_pool_alloc(gfp_flags, conf); | |
7eaceacc | 102 | if (!r10_bio) |
1da177e4 | 103 | return NULL; |
1da177e4 LT |
104 | |
105 | if (test_bit(MD_RECOVERY_SYNC, &conf->mddev->recovery)) | |
106 | nalloc = conf->copies; /* resync */ | |
107 | else | |
108 | nalloc = 2; /* recovery */ | |
109 | ||
110 | /* | |
111 | * Allocate bios. | |
112 | */ | |
113 | for (j = nalloc ; j-- ; ) { | |
6746557f | 114 | bio = bio_kmalloc(gfp_flags, RESYNC_PAGES); |
1da177e4 LT |
115 | if (!bio) |
116 | goto out_free_bio; | |
117 | r10_bio->devs[j].bio = bio; | |
118 | } | |
119 | /* | |
120 | * Allocate RESYNC_PAGES data pages and attach them | |
121 | * where needed. | |
122 | */ | |
123 | for (j = 0 ; j < nalloc; j++) { | |
124 | bio = r10_bio->devs[j].bio; | |
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 | } | |
132 | } | |
133 | ||
134 | return r10_bio; | |
135 | ||
136 | out_free_pages: | |
137 | for ( ; i > 0 ; i--) | |
1345b1d8 | 138 | safe_put_page(bio->bi_io_vec[i-1].bv_page); |
1da177e4 LT |
139 | while (j--) |
140 | for (i = 0; i < RESYNC_PAGES ; i++) | |
1345b1d8 | 141 | safe_put_page(r10_bio->devs[j].bio->bi_io_vec[i].bv_page); |
1da177e4 LT |
142 | j = -1; |
143 | out_free_bio: | |
144 | while ( ++j < nalloc ) | |
145 | bio_put(r10_bio->devs[j].bio); | |
146 | r10bio_pool_free(r10_bio, conf); | |
147 | return NULL; | |
148 | } | |
149 | ||
150 | static void r10buf_pool_free(void *__r10_bio, void *data) | |
151 | { | |
152 | int i; | |
153 | conf_t *conf = data; | |
154 | r10bio_t *r10bio = __r10_bio; | |
155 | int j; | |
156 | ||
157 | for (j=0; j < conf->copies; j++) { | |
158 | struct bio *bio = r10bio->devs[j].bio; | |
159 | if (bio) { | |
160 | for (i = 0; i < RESYNC_PAGES; i++) { | |
1345b1d8 | 161 | safe_put_page(bio->bi_io_vec[i].bv_page); |
1da177e4 LT |
162 | bio->bi_io_vec[i].bv_page = NULL; |
163 | } | |
164 | bio_put(bio); | |
165 | } | |
166 | } | |
167 | r10bio_pool_free(r10bio, conf); | |
168 | } | |
169 | ||
170 | static void put_all_bios(conf_t *conf, r10bio_t *r10_bio) | |
171 | { | |
172 | int i; | |
173 | ||
174 | for (i = 0; i < conf->copies; i++) { | |
175 | struct bio **bio = & r10_bio->devs[i].bio; | |
0eb3ff12 | 176 | if (*bio && *bio != IO_BLOCKED) |
1da177e4 LT |
177 | bio_put(*bio); |
178 | *bio = NULL; | |
179 | } | |
180 | } | |
181 | ||
858119e1 | 182 | static void free_r10bio(r10bio_t *r10_bio) |
1da177e4 | 183 | { |
070ec55d | 184 | conf_t *conf = r10_bio->mddev->private; |
1da177e4 LT |
185 | |
186 | /* | |
187 | * Wake up any possible resync thread that waits for the device | |
188 | * to go idle. | |
189 | */ | |
0a27ec96 | 190 | allow_barrier(conf); |
1da177e4 LT |
191 | |
192 | put_all_bios(conf, r10_bio); | |
193 | mempool_free(r10_bio, conf->r10bio_pool); | |
194 | } | |
195 | ||
858119e1 | 196 | static void put_buf(r10bio_t *r10_bio) |
1da177e4 | 197 | { |
070ec55d | 198 | conf_t *conf = r10_bio->mddev->private; |
1da177e4 LT |
199 | |
200 | mempool_free(r10_bio, conf->r10buf_pool); | |
201 | ||
0a27ec96 | 202 | lower_barrier(conf); |
1da177e4 LT |
203 | } |
204 | ||
205 | static void reschedule_retry(r10bio_t *r10_bio) | |
206 | { | |
207 | unsigned long flags; | |
208 | mddev_t *mddev = r10_bio->mddev; | |
070ec55d | 209 | conf_t *conf = mddev->private; |
1da177e4 LT |
210 | |
211 | spin_lock_irqsave(&conf->device_lock, flags); | |
212 | list_add(&r10_bio->retry_list, &conf->retry_list); | |
4443ae10 | 213 | conf->nr_queued ++; |
1da177e4 LT |
214 | spin_unlock_irqrestore(&conf->device_lock, flags); |
215 | ||
388667be AJ |
216 | /* wake up frozen array... */ |
217 | wake_up(&conf->wait_barrier); | |
218 | ||
1da177e4 LT |
219 | md_wakeup_thread(mddev->thread); |
220 | } | |
221 | ||
222 | /* | |
223 | * raid_end_bio_io() is called when we have finished servicing a mirrored | |
224 | * operation and are ready to return a success/failure code to the buffer | |
225 | * cache layer. | |
226 | */ | |
227 | static void raid_end_bio_io(r10bio_t *r10_bio) | |
228 | { | |
229 | struct bio *bio = r10_bio->master_bio; | |
230 | ||
6712ecf8 | 231 | bio_endio(bio, |
1da177e4 LT |
232 | test_bit(R10BIO_Uptodate, &r10_bio->state) ? 0 : -EIO); |
233 | free_r10bio(r10_bio); | |
234 | } | |
235 | ||
236 | /* | |
237 | * Update disk head position estimator based on IRQ completion info. | |
238 | */ | |
239 | static inline void update_head_pos(int slot, r10bio_t *r10_bio) | |
240 | { | |
070ec55d | 241 | conf_t *conf = r10_bio->mddev->private; |
1da177e4 LT |
242 | |
243 | conf->mirrors[r10_bio->devs[slot].devnum].head_position = | |
244 | r10_bio->devs[slot].addr + (r10_bio->sectors); | |
245 | } | |
246 | ||
6712ecf8 | 247 | static void raid10_end_read_request(struct bio *bio, int error) |
1da177e4 LT |
248 | { |
249 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
7b92813c | 250 | r10bio_t *r10_bio = bio->bi_private; |
1da177e4 | 251 | int slot, dev; |
070ec55d | 252 | conf_t *conf = r10_bio->mddev->private; |
1da177e4 | 253 | |
1da177e4 LT |
254 | |
255 | slot = r10_bio->read_slot; | |
256 | dev = r10_bio->devs[slot].devnum; | |
257 | /* | |
258 | * this branch is our 'one mirror IO has finished' event handler: | |
259 | */ | |
4443ae10 N |
260 | update_head_pos(slot, r10_bio); |
261 | ||
262 | if (uptodate) { | |
1da177e4 LT |
263 | /* |
264 | * Set R10BIO_Uptodate in our master bio, so that | |
265 | * we will return a good error code to the higher | |
266 | * levels even if IO on some other mirrored buffer fails. | |
267 | * | |
268 | * The 'master' represents the composite IO operation to | |
269 | * user-side. So if something waits for IO, then it will | |
270 | * wait for the 'master' bio. | |
271 | */ | |
272 | set_bit(R10BIO_Uptodate, &r10_bio->state); | |
1da177e4 | 273 | raid_end_bio_io(r10_bio); |
7c4e06ff | 274 | rdev_dec_pending(conf->mirrors[dev].rdev, conf->mddev); |
4443ae10 | 275 | } else { |
1da177e4 | 276 | /* |
7c4e06ff | 277 | * oops, read error - keep the refcount on the rdev |
1da177e4 LT |
278 | */ |
279 | char b[BDEVNAME_SIZE]; | |
280 | if (printk_ratelimit()) | |
128595ed N |
281 | printk(KERN_ERR "md/raid10:%s: %s: rescheduling sector %llu\n", |
282 | mdname(conf->mddev), | |
1da177e4 LT |
283 | bdevname(conf->mirrors[dev].rdev->bdev,b), (unsigned long long)r10_bio->sector); |
284 | reschedule_retry(r10_bio); | |
285 | } | |
1da177e4 LT |
286 | } |
287 | ||
6712ecf8 | 288 | static void raid10_end_write_request(struct bio *bio, int error) |
1da177e4 LT |
289 | { |
290 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
7b92813c | 291 | r10bio_t *r10_bio = bio->bi_private; |
1da177e4 | 292 | int slot, dev; |
070ec55d | 293 | conf_t *conf = r10_bio->mddev->private; |
1da177e4 | 294 | |
1da177e4 LT |
295 | for (slot = 0; slot < conf->copies; slot++) |
296 | if (r10_bio->devs[slot].bio == bio) | |
297 | break; | |
298 | dev = r10_bio->devs[slot].devnum; | |
299 | ||
300 | /* | |
301 | * this branch is our 'one mirror IO has finished' event handler: | |
302 | */ | |
6cce3b23 | 303 | if (!uptodate) { |
1da177e4 | 304 | md_error(r10_bio->mddev, conf->mirrors[dev].rdev); |
6cce3b23 N |
305 | /* an I/O failed, we can't clear the bitmap */ |
306 | set_bit(R10BIO_Degraded, &r10_bio->state); | |
307 | } else | |
1da177e4 LT |
308 | /* |
309 | * Set R10BIO_Uptodate in our master bio, so that | |
310 | * we will return a good error code for to the higher | |
311 | * levels even if IO on some other mirrored buffer fails. | |
312 | * | |
313 | * The 'master' represents the composite IO operation to | |
314 | * user-side. So if something waits for IO, then it will | |
315 | * wait for the 'master' bio. | |
316 | */ | |
317 | set_bit(R10BIO_Uptodate, &r10_bio->state); | |
318 | ||
319 | update_head_pos(slot, r10_bio); | |
320 | ||
321 | /* | |
322 | * | |
323 | * Let's see if all mirrored write operations have finished | |
324 | * already. | |
325 | */ | |
326 | if (atomic_dec_and_test(&r10_bio->remaining)) { | |
6cce3b23 N |
327 | /* clear the bitmap if all writes complete successfully */ |
328 | bitmap_endwrite(r10_bio->mddev->bitmap, r10_bio->sector, | |
329 | r10_bio->sectors, | |
330 | !test_bit(R10BIO_Degraded, &r10_bio->state), | |
331 | 0); | |
1da177e4 LT |
332 | md_write_end(r10_bio->mddev); |
333 | raid_end_bio_io(r10_bio); | |
334 | } | |
335 | ||
336 | rdev_dec_pending(conf->mirrors[dev].rdev, conf->mddev); | |
1da177e4 LT |
337 | } |
338 | ||
339 | ||
340 | /* | |
341 | * RAID10 layout manager | |
25985edc | 342 | * As well as the chunksize and raid_disks count, there are two |
1da177e4 LT |
343 | * parameters: near_copies and far_copies. |
344 | * near_copies * far_copies must be <= raid_disks. | |
345 | * Normally one of these will be 1. | |
346 | * If both are 1, we get raid0. | |
347 | * If near_copies == raid_disks, we get raid1. | |
348 | * | |
25985edc | 349 | * Chunks are laid out in raid0 style with near_copies copies of the |
1da177e4 LT |
350 | * first chunk, followed by near_copies copies of the next chunk and |
351 | * so on. | |
352 | * If far_copies > 1, then after 1/far_copies of the array has been assigned | |
353 | * as described above, we start again with a device offset of near_copies. | |
354 | * So we effectively have another copy of the whole array further down all | |
355 | * the drives, but with blocks on different drives. | |
356 | * With this layout, and block is never stored twice on the one device. | |
357 | * | |
358 | * raid10_find_phys finds the sector offset of a given virtual sector | |
c93983bf | 359 | * on each device that it is on. |
1da177e4 LT |
360 | * |
361 | * raid10_find_virt does the reverse mapping, from a device and a | |
362 | * sector offset to a virtual address | |
363 | */ | |
364 | ||
365 | static void raid10_find_phys(conf_t *conf, r10bio_t *r10bio) | |
366 | { | |
367 | int n,f; | |
368 | sector_t sector; | |
369 | sector_t chunk; | |
370 | sector_t stripe; | |
371 | int dev; | |
372 | ||
373 | int slot = 0; | |
374 | ||
375 | /* now calculate first sector/dev */ | |
376 | chunk = r10bio->sector >> conf->chunk_shift; | |
377 | sector = r10bio->sector & conf->chunk_mask; | |
378 | ||
379 | chunk *= conf->near_copies; | |
380 | stripe = chunk; | |
381 | dev = sector_div(stripe, conf->raid_disks); | |
c93983bf N |
382 | if (conf->far_offset) |
383 | stripe *= conf->far_copies; | |
1da177e4 LT |
384 | |
385 | sector += stripe << conf->chunk_shift; | |
386 | ||
387 | /* and calculate all the others */ | |
388 | for (n=0; n < conf->near_copies; n++) { | |
389 | int d = dev; | |
390 | sector_t s = sector; | |
391 | r10bio->devs[slot].addr = sector; | |
392 | r10bio->devs[slot].devnum = d; | |
393 | slot++; | |
394 | ||
395 | for (f = 1; f < conf->far_copies; f++) { | |
396 | d += conf->near_copies; | |
397 | if (d >= conf->raid_disks) | |
398 | d -= conf->raid_disks; | |
399 | s += conf->stride; | |
400 | r10bio->devs[slot].devnum = d; | |
401 | r10bio->devs[slot].addr = s; | |
402 | slot++; | |
403 | } | |
404 | dev++; | |
405 | if (dev >= conf->raid_disks) { | |
406 | dev = 0; | |
407 | sector += (conf->chunk_mask + 1); | |
408 | } | |
409 | } | |
410 | BUG_ON(slot != conf->copies); | |
411 | } | |
412 | ||
413 | static sector_t raid10_find_virt(conf_t *conf, sector_t sector, int dev) | |
414 | { | |
415 | sector_t offset, chunk, vchunk; | |
416 | ||
1da177e4 | 417 | offset = sector & conf->chunk_mask; |
c93983bf N |
418 | if (conf->far_offset) { |
419 | int fc; | |
420 | chunk = sector >> conf->chunk_shift; | |
421 | fc = sector_div(chunk, conf->far_copies); | |
422 | dev -= fc * conf->near_copies; | |
423 | if (dev < 0) | |
424 | dev += conf->raid_disks; | |
425 | } else { | |
64a742bc | 426 | while (sector >= conf->stride) { |
c93983bf N |
427 | sector -= conf->stride; |
428 | if (dev < conf->near_copies) | |
429 | dev += conf->raid_disks - conf->near_copies; | |
430 | else | |
431 | dev -= conf->near_copies; | |
432 | } | |
433 | chunk = sector >> conf->chunk_shift; | |
434 | } | |
1da177e4 LT |
435 | vchunk = chunk * conf->raid_disks + dev; |
436 | sector_div(vchunk, conf->near_copies); | |
437 | return (vchunk << conf->chunk_shift) + offset; | |
438 | } | |
439 | ||
440 | /** | |
441 | * raid10_mergeable_bvec -- tell bio layer if a two requests can be merged | |
442 | * @q: request queue | |
cc371e66 | 443 | * @bvm: properties of new bio |
1da177e4 LT |
444 | * @biovec: the request that could be merged to it. |
445 | * | |
446 | * Return amount of bytes we can accept at this offset | |
447 | * If near_copies == raid_disk, there are no striping issues, | |
448 | * but in that case, the function isn't called at all. | |
449 | */ | |
cc371e66 AK |
450 | static int raid10_mergeable_bvec(struct request_queue *q, |
451 | struct bvec_merge_data *bvm, | |
452 | struct bio_vec *biovec) | |
1da177e4 LT |
453 | { |
454 | mddev_t *mddev = q->queuedata; | |
cc371e66 | 455 | sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev); |
1da177e4 | 456 | int max; |
9d8f0363 | 457 | unsigned int chunk_sectors = mddev->chunk_sectors; |
cc371e66 | 458 | unsigned int bio_sectors = bvm->bi_size >> 9; |
1da177e4 LT |
459 | |
460 | max = (chunk_sectors - ((sector & (chunk_sectors - 1)) + bio_sectors)) << 9; | |
461 | if (max < 0) max = 0; /* bio_add cannot handle a negative return */ | |
cc371e66 AK |
462 | if (max <= biovec->bv_len && bio_sectors == 0) |
463 | return biovec->bv_len; | |
1da177e4 LT |
464 | else |
465 | return max; | |
466 | } | |
467 | ||
468 | /* | |
469 | * This routine returns the disk from which the requested read should | |
470 | * be done. There is a per-array 'next expected sequential IO' sector | |
471 | * number - if this matches on the next IO then we use the last disk. | |
472 | * There is also a per-disk 'last know head position' sector that is | |
473 | * maintained from IRQ contexts, both the normal and the resync IO | |
474 | * completion handlers update this position correctly. If there is no | |
475 | * perfect sequential match then we pick the disk whose head is closest. | |
476 | * | |
477 | * If there are 2 mirrors in the same 2 devices, performance degrades | |
478 | * because position is mirror, not device based. | |
479 | * | |
480 | * The rdev for the device selected will have nr_pending incremented. | |
481 | */ | |
482 | ||
483 | /* | |
484 | * FIXME: possibly should rethink readbalancing and do it differently | |
485 | * depending on near_copies / far_copies geometry. | |
486 | */ | |
487 | static int read_balance(conf_t *conf, r10bio_t *r10_bio) | |
488 | { | |
af3a2cd6 | 489 | const sector_t this_sector = r10_bio->sector; |
56d99121 | 490 | int disk, slot; |
1da177e4 | 491 | const int sectors = r10_bio->sectors; |
56d99121 | 492 | sector_t new_distance, best_dist; |
d6065f7b | 493 | mdk_rdev_t *rdev; |
56d99121 N |
494 | int do_balance; |
495 | int best_slot; | |
1da177e4 LT |
496 | |
497 | raid10_find_phys(conf, r10_bio); | |
498 | rcu_read_lock(); | |
56d99121 N |
499 | retry: |
500 | best_slot = -1; | |
501 | best_dist = MaxSector; | |
502 | do_balance = 1; | |
1da177e4 LT |
503 | /* |
504 | * Check if we can balance. We can balance on the whole | |
6cce3b23 N |
505 | * device if no resync is going on (recovery is ok), or below |
506 | * the resync window. We take the first readable disk when | |
507 | * above the resync window. | |
1da177e4 LT |
508 | */ |
509 | if (conf->mddev->recovery_cp < MaxSector | |
56d99121 N |
510 | && (this_sector + sectors >= conf->next_resync)) |
511 | do_balance = 0; | |
1da177e4 | 512 | |
56d99121 N |
513 | for (slot = 0; slot < conf->copies ; slot++) { |
514 | if (r10_bio->devs[slot].bio == IO_BLOCKED) | |
515 | continue; | |
1da177e4 | 516 | disk = r10_bio->devs[slot].devnum; |
56d99121 N |
517 | rdev = rcu_dereference(conf->mirrors[disk].rdev); |
518 | if (rdev == NULL) | |
1da177e4 | 519 | continue; |
56d99121 N |
520 | if (!test_bit(In_sync, &rdev->flags)) |
521 | continue; | |
522 | ||
523 | if (!do_balance) | |
524 | break; | |
1da177e4 | 525 | |
22dfdf52 N |
526 | /* This optimisation is debatable, and completely destroys |
527 | * sequential read speed for 'far copies' arrays. So only | |
528 | * keep it for 'near' arrays, and review those later. | |
529 | */ | |
56d99121 | 530 | if (conf->near_copies > 1 && !atomic_read(&rdev->nr_pending)) |
1da177e4 | 531 | break; |
8ed3a195 KS |
532 | |
533 | /* for far > 1 always use the lowest address */ | |
534 | if (conf->far_copies > 1) | |
56d99121 | 535 | new_distance = r10_bio->devs[slot].addr; |
8ed3a195 | 536 | else |
56d99121 N |
537 | new_distance = abs(r10_bio->devs[slot].addr - |
538 | conf->mirrors[disk].head_position); | |
539 | if (new_distance < best_dist) { | |
540 | best_dist = new_distance; | |
541 | best_slot = slot; | |
1da177e4 LT |
542 | } |
543 | } | |
56d99121 N |
544 | if (slot == conf->copies) |
545 | slot = best_slot; | |
1da177e4 | 546 | |
56d99121 N |
547 | if (slot >= 0) { |
548 | disk = r10_bio->devs[slot].devnum; | |
549 | rdev = rcu_dereference(conf->mirrors[disk].rdev); | |
550 | if (!rdev) | |
551 | goto retry; | |
552 | atomic_inc(&rdev->nr_pending); | |
553 | if (test_bit(Faulty, &rdev->flags)) { | |
554 | /* Cannot risk returning a device that failed | |
555 | * before we inc'ed nr_pending | |
556 | */ | |
557 | rdev_dec_pending(rdev, conf->mddev); | |
558 | goto retry; | |
559 | } | |
560 | r10_bio->read_slot = slot; | |
561 | } else | |
29fc7e3e | 562 | disk = -1; |
1da177e4 LT |
563 | rcu_read_unlock(); |
564 | ||
565 | return disk; | |
566 | } | |
567 | ||
0d129228 N |
568 | static int raid10_congested(void *data, int bits) |
569 | { | |
570 | mddev_t *mddev = data; | |
070ec55d | 571 | conf_t *conf = mddev->private; |
0d129228 N |
572 | int i, ret = 0; |
573 | ||
3fa841d7 N |
574 | if (mddev_congested(mddev, bits)) |
575 | return 1; | |
0d129228 | 576 | rcu_read_lock(); |
84707f38 | 577 | for (i = 0; i < conf->raid_disks && ret == 0; i++) { |
0d129228 N |
578 | mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev); |
579 | if (rdev && !test_bit(Faulty, &rdev->flags)) { | |
165125e1 | 580 | struct request_queue *q = bdev_get_queue(rdev->bdev); |
0d129228 N |
581 | |
582 | ret |= bdi_congested(&q->backing_dev_info, bits); | |
583 | } | |
584 | } | |
585 | rcu_read_unlock(); | |
586 | return ret; | |
587 | } | |
588 | ||
7eaceacc | 589 | static void flush_pending_writes(conf_t *conf) |
a35e63ef N |
590 | { |
591 | /* Any writes that have been queued but are awaiting | |
592 | * bitmap updates get flushed here. | |
a35e63ef | 593 | */ |
a35e63ef N |
594 | spin_lock_irq(&conf->device_lock); |
595 | ||
596 | if (conf->pending_bio_list.head) { | |
597 | struct bio *bio; | |
598 | bio = bio_list_get(&conf->pending_bio_list); | |
a35e63ef N |
599 | spin_unlock_irq(&conf->device_lock); |
600 | /* flush any pending bitmap writes to disk | |
601 | * before proceeding w/ I/O */ | |
602 | bitmap_unplug(conf->mddev->bitmap); | |
603 | ||
604 | while (bio) { /* submit pending writes */ | |
605 | struct bio *next = bio->bi_next; | |
606 | bio->bi_next = NULL; | |
607 | generic_make_request(bio); | |
608 | bio = next; | |
609 | } | |
a35e63ef N |
610 | } else |
611 | spin_unlock_irq(&conf->device_lock); | |
a35e63ef | 612 | } |
7eaceacc | 613 | |
0a27ec96 N |
614 | /* Barriers.... |
615 | * Sometimes we need to suspend IO while we do something else, | |
616 | * either some resync/recovery, or reconfigure the array. | |
617 | * To do this we raise a 'barrier'. | |
618 | * The 'barrier' is a counter that can be raised multiple times | |
619 | * to count how many activities are happening which preclude | |
620 | * normal IO. | |
621 | * We can only raise the barrier if there is no pending IO. | |
622 | * i.e. if nr_pending == 0. | |
623 | * We choose only to raise the barrier if no-one is waiting for the | |
624 | * barrier to go down. This means that as soon as an IO request | |
625 | * is ready, no other operations which require a barrier will start | |
626 | * until the IO request has had a chance. | |
627 | * | |
628 | * So: regular IO calls 'wait_barrier'. When that returns there | |
629 | * is no backgroup IO happening, It must arrange to call | |
630 | * allow_barrier when it has finished its IO. | |
631 | * backgroup IO calls must call raise_barrier. Once that returns | |
632 | * there is no normal IO happeing. It must arrange to call | |
633 | * lower_barrier when the particular background IO completes. | |
1da177e4 | 634 | */ |
1da177e4 | 635 | |
6cce3b23 | 636 | static void raise_barrier(conf_t *conf, int force) |
1da177e4 | 637 | { |
6cce3b23 | 638 | BUG_ON(force && !conf->barrier); |
1da177e4 | 639 | spin_lock_irq(&conf->resync_lock); |
0a27ec96 | 640 | |
6cce3b23 N |
641 | /* Wait until no block IO is waiting (unless 'force') */ |
642 | wait_event_lock_irq(conf->wait_barrier, force || !conf->nr_waiting, | |
c3b328ac | 643 | conf->resync_lock, ); |
0a27ec96 N |
644 | |
645 | /* block any new IO from starting */ | |
646 | conf->barrier++; | |
647 | ||
c3b328ac | 648 | /* Now wait for all pending IO to complete */ |
0a27ec96 N |
649 | wait_event_lock_irq(conf->wait_barrier, |
650 | !conf->nr_pending && conf->barrier < RESYNC_DEPTH, | |
c3b328ac | 651 | conf->resync_lock, ); |
0a27ec96 N |
652 | |
653 | spin_unlock_irq(&conf->resync_lock); | |
654 | } | |
655 | ||
656 | static void lower_barrier(conf_t *conf) | |
657 | { | |
658 | unsigned long flags; | |
659 | spin_lock_irqsave(&conf->resync_lock, flags); | |
660 | conf->barrier--; | |
661 | spin_unlock_irqrestore(&conf->resync_lock, flags); | |
662 | wake_up(&conf->wait_barrier); | |
663 | } | |
664 | ||
665 | static void wait_barrier(conf_t *conf) | |
666 | { | |
667 | spin_lock_irq(&conf->resync_lock); | |
668 | if (conf->barrier) { | |
669 | conf->nr_waiting++; | |
670 | wait_event_lock_irq(conf->wait_barrier, !conf->barrier, | |
671 | conf->resync_lock, | |
c3b328ac | 672 | ); |
0a27ec96 | 673 | conf->nr_waiting--; |
1da177e4 | 674 | } |
0a27ec96 | 675 | conf->nr_pending++; |
1da177e4 LT |
676 | spin_unlock_irq(&conf->resync_lock); |
677 | } | |
678 | ||
0a27ec96 N |
679 | static void allow_barrier(conf_t *conf) |
680 | { | |
681 | unsigned long flags; | |
682 | spin_lock_irqsave(&conf->resync_lock, flags); | |
683 | conf->nr_pending--; | |
684 | spin_unlock_irqrestore(&conf->resync_lock, flags); | |
685 | wake_up(&conf->wait_barrier); | |
686 | } | |
687 | ||
4443ae10 N |
688 | static void freeze_array(conf_t *conf) |
689 | { | |
690 | /* stop syncio and normal IO and wait for everything to | |
f188593e | 691 | * go quiet. |
4443ae10 | 692 | * We increment barrier and nr_waiting, and then |
1c830532 N |
693 | * wait until nr_pending match nr_queued+1 |
694 | * This is called in the context of one normal IO request | |
695 | * that has failed. Thus any sync request that might be pending | |
696 | * will be blocked by nr_pending, and we need to wait for | |
697 | * pending IO requests to complete or be queued for re-try. | |
698 | * Thus the number queued (nr_queued) plus this request (1) | |
699 | * must match the number of pending IOs (nr_pending) before | |
700 | * we continue. | |
4443ae10 N |
701 | */ |
702 | spin_lock_irq(&conf->resync_lock); | |
703 | conf->barrier++; | |
704 | conf->nr_waiting++; | |
705 | wait_event_lock_irq(conf->wait_barrier, | |
1c830532 | 706 | conf->nr_pending == conf->nr_queued+1, |
4443ae10 | 707 | conf->resync_lock, |
c3b328ac N |
708 | flush_pending_writes(conf)); |
709 | ||
4443ae10 N |
710 | spin_unlock_irq(&conf->resync_lock); |
711 | } | |
712 | ||
713 | static void unfreeze_array(conf_t *conf) | |
714 | { | |
715 | /* reverse the effect of the freeze */ | |
716 | spin_lock_irq(&conf->resync_lock); | |
717 | conf->barrier--; | |
718 | conf->nr_waiting--; | |
719 | wake_up(&conf->wait_barrier); | |
720 | spin_unlock_irq(&conf->resync_lock); | |
721 | } | |
722 | ||
21a52c6d | 723 | static int make_request(mddev_t *mddev, struct bio * bio) |
1da177e4 | 724 | { |
070ec55d | 725 | conf_t *conf = mddev->private; |
1da177e4 LT |
726 | mirror_info_t *mirror; |
727 | r10bio_t *r10_bio; | |
728 | struct bio *read_bio; | |
729 | int i; | |
730 | int chunk_sects = conf->chunk_mask + 1; | |
a362357b | 731 | const int rw = bio_data_dir(bio); |
2c7d46ec | 732 | const unsigned long do_sync = (bio->bi_rw & REQ_SYNC); |
e9c7469b | 733 | const unsigned long do_fua = (bio->bi_rw & REQ_FUA); |
6cce3b23 | 734 | unsigned long flags; |
6bfe0b49 | 735 | mdk_rdev_t *blocked_rdev; |
c3b328ac | 736 | int plugged; |
1da177e4 | 737 | |
e9c7469b TH |
738 | if (unlikely(bio->bi_rw & REQ_FLUSH)) { |
739 | md_flush_request(mddev, bio); | |
e5dcdd80 N |
740 | return 0; |
741 | } | |
742 | ||
1da177e4 LT |
743 | /* If this request crosses a chunk boundary, we need to |
744 | * split it. This will only happen for 1 PAGE (or less) requests. | |
745 | */ | |
746 | if (unlikely( (bio->bi_sector & conf->chunk_mask) + (bio->bi_size >> 9) | |
747 | > chunk_sects && | |
748 | conf->near_copies < conf->raid_disks)) { | |
749 | struct bio_pair *bp; | |
750 | /* Sanity check -- queue functions should prevent this happening */ | |
751 | if (bio->bi_vcnt != 1 || | |
752 | bio->bi_idx != 0) | |
753 | goto bad_map; | |
754 | /* This is a one page bio that upper layers | |
755 | * refuse to split for us, so we need to split it. | |
756 | */ | |
6feef531 | 757 | bp = bio_split(bio, |
1da177e4 | 758 | chunk_sects - (bio->bi_sector & (chunk_sects - 1)) ); |
51e9ac77 N |
759 | |
760 | /* Each of these 'make_request' calls will call 'wait_barrier'. | |
761 | * If the first succeeds but the second blocks due to the resync | |
762 | * thread raising the barrier, we will deadlock because the | |
763 | * IO to the underlying device will be queued in generic_make_request | |
764 | * and will never complete, so will never reduce nr_pending. | |
765 | * So increment nr_waiting here so no new raise_barriers will | |
766 | * succeed, and so the second wait_barrier cannot block. | |
767 | */ | |
768 | spin_lock_irq(&conf->resync_lock); | |
769 | conf->nr_waiting++; | |
770 | spin_unlock_irq(&conf->resync_lock); | |
771 | ||
21a52c6d | 772 | if (make_request(mddev, &bp->bio1)) |
1da177e4 | 773 | generic_make_request(&bp->bio1); |
21a52c6d | 774 | if (make_request(mddev, &bp->bio2)) |
1da177e4 LT |
775 | generic_make_request(&bp->bio2); |
776 | ||
51e9ac77 N |
777 | spin_lock_irq(&conf->resync_lock); |
778 | conf->nr_waiting--; | |
779 | wake_up(&conf->wait_barrier); | |
780 | spin_unlock_irq(&conf->resync_lock); | |
781 | ||
1da177e4 LT |
782 | bio_pair_release(bp); |
783 | return 0; | |
784 | bad_map: | |
128595ed N |
785 | printk("md/raid10:%s: make_request bug: can't convert block across chunks" |
786 | " or bigger than %dk %llu %d\n", mdname(mddev), chunk_sects/2, | |
1da177e4 LT |
787 | (unsigned long long)bio->bi_sector, bio->bi_size >> 10); |
788 | ||
6712ecf8 | 789 | bio_io_error(bio); |
1da177e4 LT |
790 | return 0; |
791 | } | |
792 | ||
3d310eb7 | 793 | md_write_start(mddev, bio); |
06d91a5f | 794 | |
1da177e4 LT |
795 | /* |
796 | * Register the new request and wait if the reconstruction | |
797 | * thread has put up a bar for new requests. | |
798 | * Continue immediately if no resync is active currently. | |
799 | */ | |
0a27ec96 | 800 | wait_barrier(conf); |
1da177e4 | 801 | |
1da177e4 LT |
802 | r10_bio = mempool_alloc(conf->r10bio_pool, GFP_NOIO); |
803 | ||
804 | r10_bio->master_bio = bio; | |
805 | r10_bio->sectors = bio->bi_size >> 9; | |
806 | ||
807 | r10_bio->mddev = mddev; | |
808 | r10_bio->sector = bio->bi_sector; | |
6cce3b23 | 809 | r10_bio->state = 0; |
1da177e4 | 810 | |
a362357b | 811 | if (rw == READ) { |
1da177e4 LT |
812 | /* |
813 | * read balancing logic: | |
814 | */ | |
815 | int disk = read_balance(conf, r10_bio); | |
816 | int slot = r10_bio->read_slot; | |
817 | if (disk < 0) { | |
818 | raid_end_bio_io(r10_bio); | |
819 | return 0; | |
820 | } | |
821 | mirror = conf->mirrors + disk; | |
822 | ||
a167f663 | 823 | read_bio = bio_clone_mddev(bio, GFP_NOIO, mddev); |
1da177e4 LT |
824 | |
825 | r10_bio->devs[slot].bio = read_bio; | |
826 | ||
827 | read_bio->bi_sector = r10_bio->devs[slot].addr + | |
828 | mirror->rdev->data_offset; | |
829 | read_bio->bi_bdev = mirror->rdev->bdev; | |
830 | read_bio->bi_end_io = raid10_end_read_request; | |
7b6d91da | 831 | read_bio->bi_rw = READ | do_sync; |
1da177e4 LT |
832 | read_bio->bi_private = r10_bio; |
833 | ||
834 | generic_make_request(read_bio); | |
835 | return 0; | |
836 | } | |
837 | ||
838 | /* | |
839 | * WRITE: | |
840 | */ | |
6bfe0b49 | 841 | /* first select target devices under rcu_lock and |
1da177e4 LT |
842 | * inc refcount on their rdev. Record them by setting |
843 | * bios[x] to bio | |
844 | */ | |
c3b328ac N |
845 | plugged = mddev_check_plugged(mddev); |
846 | ||
1da177e4 | 847 | raid10_find_phys(conf, r10_bio); |
6bfe0b49 | 848 | retry_write: |
cb6969e8 | 849 | blocked_rdev = NULL; |
1da177e4 LT |
850 | rcu_read_lock(); |
851 | for (i = 0; i < conf->copies; i++) { | |
852 | int d = r10_bio->devs[i].devnum; | |
d6065f7b | 853 | mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[d].rdev); |
6bfe0b49 DW |
854 | if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) { |
855 | atomic_inc(&rdev->nr_pending); | |
856 | blocked_rdev = rdev; | |
857 | break; | |
858 | } | |
859 | if (rdev && !test_bit(Faulty, &rdev->flags)) { | |
d6065f7b | 860 | atomic_inc(&rdev->nr_pending); |
1da177e4 | 861 | r10_bio->devs[i].bio = bio; |
6cce3b23 | 862 | } else { |
1da177e4 | 863 | r10_bio->devs[i].bio = NULL; |
6cce3b23 N |
864 | set_bit(R10BIO_Degraded, &r10_bio->state); |
865 | } | |
1da177e4 LT |
866 | } |
867 | rcu_read_unlock(); | |
868 | ||
6bfe0b49 DW |
869 | if (unlikely(blocked_rdev)) { |
870 | /* Have to wait for this device to get unblocked, then retry */ | |
871 | int j; | |
872 | int d; | |
873 | ||
874 | for (j = 0; j < i; j++) | |
875 | if (r10_bio->devs[j].bio) { | |
876 | d = r10_bio->devs[j].devnum; | |
877 | rdev_dec_pending(conf->mirrors[d].rdev, mddev); | |
878 | } | |
879 | allow_barrier(conf); | |
880 | md_wait_for_blocked_rdev(blocked_rdev, mddev); | |
881 | wait_barrier(conf); | |
882 | goto retry_write; | |
883 | } | |
884 | ||
4e78064f N |
885 | atomic_set(&r10_bio->remaining, 1); |
886 | bitmap_startwrite(mddev->bitmap, bio->bi_sector, r10_bio->sectors, 0); | |
06d91a5f | 887 | |
1da177e4 LT |
888 | for (i = 0; i < conf->copies; i++) { |
889 | struct bio *mbio; | |
890 | int d = r10_bio->devs[i].devnum; | |
891 | if (!r10_bio->devs[i].bio) | |
892 | continue; | |
893 | ||
a167f663 | 894 | mbio = bio_clone_mddev(bio, GFP_NOIO, mddev); |
1da177e4 LT |
895 | r10_bio->devs[i].bio = mbio; |
896 | ||
897 | mbio->bi_sector = r10_bio->devs[i].addr+ | |
898 | conf->mirrors[d].rdev->data_offset; | |
899 | mbio->bi_bdev = conf->mirrors[d].rdev->bdev; | |
900 | mbio->bi_end_io = raid10_end_write_request; | |
e9c7469b | 901 | mbio->bi_rw = WRITE | do_sync | do_fua; |
1da177e4 LT |
902 | mbio->bi_private = r10_bio; |
903 | ||
904 | atomic_inc(&r10_bio->remaining); | |
4e78064f N |
905 | spin_lock_irqsave(&conf->device_lock, flags); |
906 | bio_list_add(&conf->pending_bio_list, mbio); | |
4e78064f | 907 | spin_unlock_irqrestore(&conf->device_lock, flags); |
1da177e4 LT |
908 | } |
909 | ||
4e78064f N |
910 | if (atomic_dec_and_test(&r10_bio->remaining)) { |
911 | /* This matches the end of raid10_end_write_request() */ | |
912 | bitmap_endwrite(r10_bio->mddev->bitmap, r10_bio->sector, | |
913 | r10_bio->sectors, | |
914 | !test_bit(R10BIO_Degraded, &r10_bio->state), | |
915 | 0); | |
f6f953aa AR |
916 | md_write_end(mddev); |
917 | raid_end_bio_io(r10_bio); | |
f6f953aa AR |
918 | } |
919 | ||
a35e63ef N |
920 | /* In case raid10d snuck in to freeze_array */ |
921 | wake_up(&conf->wait_barrier); | |
922 | ||
c3b328ac | 923 | if (do_sync || !mddev->bitmap || !plugged) |
e3881a68 | 924 | md_wakeup_thread(mddev->thread); |
1da177e4 LT |
925 | return 0; |
926 | } | |
927 | ||
928 | static void status(struct seq_file *seq, mddev_t *mddev) | |
929 | { | |
070ec55d | 930 | conf_t *conf = mddev->private; |
1da177e4 LT |
931 | int i; |
932 | ||
933 | if (conf->near_copies < conf->raid_disks) | |
9d8f0363 | 934 | seq_printf(seq, " %dK chunks", mddev->chunk_sectors / 2); |
1da177e4 LT |
935 | if (conf->near_copies > 1) |
936 | seq_printf(seq, " %d near-copies", conf->near_copies); | |
c93983bf N |
937 | if (conf->far_copies > 1) { |
938 | if (conf->far_offset) | |
939 | seq_printf(seq, " %d offset-copies", conf->far_copies); | |
940 | else | |
941 | seq_printf(seq, " %d far-copies", conf->far_copies); | |
942 | } | |
1da177e4 | 943 | seq_printf(seq, " [%d/%d] [", conf->raid_disks, |
76186dd8 | 944 | conf->raid_disks - mddev->degraded); |
1da177e4 LT |
945 | for (i = 0; i < conf->raid_disks; i++) |
946 | seq_printf(seq, "%s", | |
947 | conf->mirrors[i].rdev && | |
b2d444d7 | 948 | test_bit(In_sync, &conf->mirrors[i].rdev->flags) ? "U" : "_"); |
1da177e4 LT |
949 | seq_printf(seq, "]"); |
950 | } | |
951 | ||
952 | static void error(mddev_t *mddev, mdk_rdev_t *rdev) | |
953 | { | |
954 | char b[BDEVNAME_SIZE]; | |
070ec55d | 955 | conf_t *conf = mddev->private; |
1da177e4 LT |
956 | |
957 | /* | |
958 | * If it is not operational, then we have already marked it as dead | |
959 | * else if it is the last working disks, ignore the error, let the | |
960 | * next level up know. | |
961 | * else mark the drive as failed | |
962 | */ | |
b2d444d7 | 963 | if (test_bit(In_sync, &rdev->flags) |
76186dd8 | 964 | && conf->raid_disks-mddev->degraded == 1) |
1da177e4 LT |
965 | /* |
966 | * Don't fail the drive, just return an IO error. | |
967 | * The test should really be more sophisticated than | |
968 | * "working_disks == 1", but it isn't critical, and | |
969 | * can wait until we do more sophisticated "is the drive | |
970 | * really dead" tests... | |
971 | */ | |
972 | return; | |
c04be0aa N |
973 | if (test_and_clear_bit(In_sync, &rdev->flags)) { |
974 | unsigned long flags; | |
975 | spin_lock_irqsave(&conf->device_lock, flags); | |
1da177e4 | 976 | mddev->degraded++; |
c04be0aa | 977 | spin_unlock_irqrestore(&conf->device_lock, flags); |
1da177e4 LT |
978 | /* |
979 | * if recovery is running, make sure it aborts. | |
980 | */ | |
dfc70645 | 981 | set_bit(MD_RECOVERY_INTR, &mddev->recovery); |
1da177e4 | 982 | } |
b2d444d7 | 983 | set_bit(Faulty, &rdev->flags); |
850b2b42 | 984 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
067032bc JP |
985 | printk(KERN_ALERT |
986 | "md/raid10:%s: Disk failure on %s, disabling device.\n" | |
987 | "md/raid10:%s: Operation continuing on %d devices.\n", | |
128595ed N |
988 | mdname(mddev), bdevname(rdev->bdev, b), |
989 | mdname(mddev), conf->raid_disks - mddev->degraded); | |
1da177e4 LT |
990 | } |
991 | ||
992 | static void print_conf(conf_t *conf) | |
993 | { | |
994 | int i; | |
995 | mirror_info_t *tmp; | |
996 | ||
128595ed | 997 | printk(KERN_DEBUG "RAID10 conf printout:\n"); |
1da177e4 | 998 | if (!conf) { |
128595ed | 999 | printk(KERN_DEBUG "(!conf)\n"); |
1da177e4 LT |
1000 | return; |
1001 | } | |
128595ed | 1002 | printk(KERN_DEBUG " --- wd:%d rd:%d\n", conf->raid_disks - conf->mddev->degraded, |
1da177e4 LT |
1003 | conf->raid_disks); |
1004 | ||
1005 | for (i = 0; i < conf->raid_disks; i++) { | |
1006 | char b[BDEVNAME_SIZE]; | |
1007 | tmp = conf->mirrors + i; | |
1008 | if (tmp->rdev) | |
128595ed | 1009 | printk(KERN_DEBUG " disk %d, wo:%d, o:%d, dev:%s\n", |
b2d444d7 N |
1010 | i, !test_bit(In_sync, &tmp->rdev->flags), |
1011 | !test_bit(Faulty, &tmp->rdev->flags), | |
1da177e4 LT |
1012 | bdevname(tmp->rdev->bdev,b)); |
1013 | } | |
1014 | } | |
1015 | ||
1016 | static void close_sync(conf_t *conf) | |
1017 | { | |
0a27ec96 N |
1018 | wait_barrier(conf); |
1019 | allow_barrier(conf); | |
1da177e4 LT |
1020 | |
1021 | mempool_destroy(conf->r10buf_pool); | |
1022 | conf->r10buf_pool = NULL; | |
1023 | } | |
1024 | ||
6d508242 N |
1025 | /* check if there are enough drives for |
1026 | * every block to appear on atleast one | |
1027 | */ | |
1028 | static int enough(conf_t *conf) | |
1029 | { | |
1030 | int first = 0; | |
1031 | ||
1032 | do { | |
1033 | int n = conf->copies; | |
1034 | int cnt = 0; | |
1035 | while (n--) { | |
1036 | if (conf->mirrors[first].rdev) | |
1037 | cnt++; | |
1038 | first = (first+1) % conf->raid_disks; | |
1039 | } | |
1040 | if (cnt == 0) | |
1041 | return 0; | |
1042 | } while (first != 0); | |
1043 | return 1; | |
1044 | } | |
1045 | ||
1da177e4 LT |
1046 | static int raid10_spare_active(mddev_t *mddev) |
1047 | { | |
1048 | int i; | |
1049 | conf_t *conf = mddev->private; | |
1050 | mirror_info_t *tmp; | |
6b965620 N |
1051 | int count = 0; |
1052 | unsigned long flags; | |
1da177e4 LT |
1053 | |
1054 | /* | |
1055 | * Find all non-in_sync disks within the RAID10 configuration | |
1056 | * and mark them in_sync | |
1057 | */ | |
1058 | for (i = 0; i < conf->raid_disks; i++) { | |
1059 | tmp = conf->mirrors + i; | |
1060 | if (tmp->rdev | |
b2d444d7 | 1061 | && !test_bit(Faulty, &tmp->rdev->flags) |
c04be0aa | 1062 | && !test_and_set_bit(In_sync, &tmp->rdev->flags)) { |
6b965620 | 1063 | count++; |
e6ffbcb6 | 1064 | sysfs_notify_dirent(tmp->rdev->sysfs_state); |
1da177e4 LT |
1065 | } |
1066 | } | |
6b965620 N |
1067 | spin_lock_irqsave(&conf->device_lock, flags); |
1068 | mddev->degraded -= count; | |
1069 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
1da177e4 LT |
1070 | |
1071 | print_conf(conf); | |
6b965620 | 1072 | return count; |
1da177e4 LT |
1073 | } |
1074 | ||
1075 | ||
1076 | static int raid10_add_disk(mddev_t *mddev, mdk_rdev_t *rdev) | |
1077 | { | |
1078 | conf_t *conf = mddev->private; | |
199050ea | 1079 | int err = -EEXIST; |
1da177e4 LT |
1080 | int mirror; |
1081 | mirror_info_t *p; | |
6c2fce2e | 1082 | int first = 0; |
84707f38 | 1083 | int last = conf->raid_disks - 1; |
1da177e4 LT |
1084 | |
1085 | if (mddev->recovery_cp < MaxSector) | |
1086 | /* only hot-add to in-sync arrays, as recovery is | |
1087 | * very different from resync | |
1088 | */ | |
199050ea | 1089 | return -EBUSY; |
6d508242 | 1090 | if (!enough(conf)) |
199050ea | 1091 | return -EINVAL; |
1da177e4 | 1092 | |
a53a6c85 | 1093 | if (rdev->raid_disk >= 0) |
6c2fce2e | 1094 | first = last = rdev->raid_disk; |
1da177e4 | 1095 | |
6cce3b23 | 1096 | if (rdev->saved_raid_disk >= 0 && |
6c2fce2e | 1097 | rdev->saved_raid_disk >= first && |
6cce3b23 N |
1098 | conf->mirrors[rdev->saved_raid_disk].rdev == NULL) |
1099 | mirror = rdev->saved_raid_disk; | |
1100 | else | |
6c2fce2e NB |
1101 | mirror = first; |
1102 | for ( ; mirror <= last ; mirror++) | |
1da177e4 LT |
1103 | if ( !(p=conf->mirrors+mirror)->rdev) { |
1104 | ||
8f6c2e4b MP |
1105 | disk_stack_limits(mddev->gendisk, rdev->bdev, |
1106 | rdev->data_offset << 9); | |
627a2d3c N |
1107 | /* as we don't honour merge_bvec_fn, we must |
1108 | * never risk violating it, so limit | |
1109 | * ->max_segments to one lying with a single | |
1110 | * page, as a one page request is never in | |
1111 | * violation. | |
1da177e4 | 1112 | */ |
627a2d3c N |
1113 | if (rdev->bdev->bd_disk->queue->merge_bvec_fn) { |
1114 | blk_queue_max_segments(mddev->queue, 1); | |
1115 | blk_queue_segment_boundary(mddev->queue, | |
1116 | PAGE_CACHE_SIZE - 1); | |
1117 | } | |
1da177e4 LT |
1118 | |
1119 | p->head_position = 0; | |
1120 | rdev->raid_disk = mirror; | |
199050ea | 1121 | err = 0; |
6cce3b23 N |
1122 | if (rdev->saved_raid_disk != mirror) |
1123 | conf->fullsync = 1; | |
d6065f7b | 1124 | rcu_assign_pointer(p->rdev, rdev); |
1da177e4 LT |
1125 | break; |
1126 | } | |
1127 | ||
ac5e7113 | 1128 | md_integrity_add_rdev(rdev, mddev); |
1da177e4 | 1129 | print_conf(conf); |
199050ea | 1130 | return err; |
1da177e4 LT |
1131 | } |
1132 | ||
1133 | static int raid10_remove_disk(mddev_t *mddev, int number) | |
1134 | { | |
1135 | conf_t *conf = mddev->private; | |
1136 | int err = 0; | |
1137 | mdk_rdev_t *rdev; | |
1138 | mirror_info_t *p = conf->mirrors+ number; | |
1139 | ||
1140 | print_conf(conf); | |
1141 | rdev = p->rdev; | |
1142 | if (rdev) { | |
b2d444d7 | 1143 | if (test_bit(In_sync, &rdev->flags) || |
1da177e4 LT |
1144 | atomic_read(&rdev->nr_pending)) { |
1145 | err = -EBUSY; | |
1146 | goto abort; | |
1147 | } | |
dfc70645 N |
1148 | /* Only remove faulty devices in recovery |
1149 | * is not possible. | |
1150 | */ | |
1151 | if (!test_bit(Faulty, &rdev->flags) && | |
1152 | enough(conf)) { | |
1153 | err = -EBUSY; | |
1154 | goto abort; | |
1155 | } | |
1da177e4 | 1156 | p->rdev = NULL; |
fbd568a3 | 1157 | synchronize_rcu(); |
1da177e4 LT |
1158 | if (atomic_read(&rdev->nr_pending)) { |
1159 | /* lost the race, try later */ | |
1160 | err = -EBUSY; | |
1161 | p->rdev = rdev; | |
ac5e7113 | 1162 | goto abort; |
1da177e4 | 1163 | } |
a91a2785 | 1164 | err = md_integrity_register(mddev); |
1da177e4 LT |
1165 | } |
1166 | abort: | |
1167 | ||
1168 | print_conf(conf); | |
1169 | return err; | |
1170 | } | |
1171 | ||
1172 | ||
6712ecf8 | 1173 | static void end_sync_read(struct bio *bio, int error) |
1da177e4 | 1174 | { |
7b92813c | 1175 | r10bio_t *r10_bio = bio->bi_private; |
070ec55d | 1176 | conf_t *conf = r10_bio->mddev->private; |
1da177e4 LT |
1177 | int i,d; |
1178 | ||
1da177e4 LT |
1179 | for (i=0; i<conf->copies; i++) |
1180 | if (r10_bio->devs[i].bio == bio) | |
1181 | break; | |
b6385483 | 1182 | BUG_ON(i == conf->copies); |
1da177e4 LT |
1183 | update_head_pos(i, r10_bio); |
1184 | d = r10_bio->devs[i].devnum; | |
0eb3ff12 N |
1185 | |
1186 | if (test_bit(BIO_UPTODATE, &bio->bi_flags)) | |
1187 | set_bit(R10BIO_Uptodate, &r10_bio->state); | |
4dbcdc75 N |
1188 | else { |
1189 | atomic_add(r10_bio->sectors, | |
1190 | &conf->mirrors[d].rdev->corrected_errors); | |
1191 | if (!test_bit(MD_RECOVERY_SYNC, &conf->mddev->recovery)) | |
1192 | md_error(r10_bio->mddev, | |
1193 | conf->mirrors[d].rdev); | |
1194 | } | |
1da177e4 LT |
1195 | |
1196 | /* for reconstruct, we always reschedule after a read. | |
1197 | * for resync, only after all reads | |
1198 | */ | |
73d5c38a | 1199 | rdev_dec_pending(conf->mirrors[d].rdev, conf->mddev); |
1da177e4 LT |
1200 | if (test_bit(R10BIO_IsRecover, &r10_bio->state) || |
1201 | atomic_dec_and_test(&r10_bio->remaining)) { | |
1202 | /* we have read all the blocks, | |
1203 | * do the comparison in process context in raid10d | |
1204 | */ | |
1205 | reschedule_retry(r10_bio); | |
1206 | } | |
1da177e4 LT |
1207 | } |
1208 | ||
6712ecf8 | 1209 | static void end_sync_write(struct bio *bio, int error) |
1da177e4 LT |
1210 | { |
1211 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
7b92813c | 1212 | r10bio_t *r10_bio = bio->bi_private; |
1da177e4 | 1213 | mddev_t *mddev = r10_bio->mddev; |
070ec55d | 1214 | conf_t *conf = mddev->private; |
1da177e4 LT |
1215 | int i,d; |
1216 | ||
1da177e4 LT |
1217 | for (i = 0; i < conf->copies; i++) |
1218 | if (r10_bio->devs[i].bio == bio) | |
1219 | break; | |
1220 | d = r10_bio->devs[i].devnum; | |
1221 | ||
1222 | if (!uptodate) | |
1223 | md_error(mddev, conf->mirrors[d].rdev); | |
dfc70645 | 1224 | |
1da177e4 LT |
1225 | update_head_pos(i, r10_bio); |
1226 | ||
73d5c38a | 1227 | rdev_dec_pending(conf->mirrors[d].rdev, mddev); |
1da177e4 LT |
1228 | while (atomic_dec_and_test(&r10_bio->remaining)) { |
1229 | if (r10_bio->master_bio == NULL) { | |
1230 | /* the primary of several recovery bios */ | |
73d5c38a | 1231 | sector_t s = r10_bio->sectors; |
1da177e4 | 1232 | put_buf(r10_bio); |
73d5c38a | 1233 | md_done_sync(mddev, s, 1); |
1da177e4 LT |
1234 | break; |
1235 | } else { | |
1236 | r10bio_t *r10_bio2 = (r10bio_t *)r10_bio->master_bio; | |
1237 | put_buf(r10_bio); | |
1238 | r10_bio = r10_bio2; | |
1239 | } | |
1240 | } | |
1da177e4 LT |
1241 | } |
1242 | ||
1243 | /* | |
1244 | * Note: sync and recover and handled very differently for raid10 | |
1245 | * This code is for resync. | |
1246 | * For resync, we read through virtual addresses and read all blocks. | |
1247 | * If there is any error, we schedule a write. The lowest numbered | |
1248 | * drive is authoritative. | |
1249 | * However requests come for physical address, so we need to map. | |
1250 | * For every physical address there are raid_disks/copies virtual addresses, | |
1251 | * which is always are least one, but is not necessarly an integer. | |
1252 | * This means that a physical address can span multiple chunks, so we may | |
1253 | * have to submit multiple io requests for a single sync request. | |
1254 | */ | |
1255 | /* | |
1256 | * We check if all blocks are in-sync and only write to blocks that | |
1257 | * aren't in sync | |
1258 | */ | |
1259 | static void sync_request_write(mddev_t *mddev, r10bio_t *r10_bio) | |
1260 | { | |
070ec55d | 1261 | conf_t *conf = mddev->private; |
1da177e4 LT |
1262 | int i, first; |
1263 | struct bio *tbio, *fbio; | |
1264 | ||
1265 | atomic_set(&r10_bio->remaining, 1); | |
1266 | ||
1267 | /* find the first device with a block */ | |
1268 | for (i=0; i<conf->copies; i++) | |
1269 | if (test_bit(BIO_UPTODATE, &r10_bio->devs[i].bio->bi_flags)) | |
1270 | break; | |
1271 | ||
1272 | if (i == conf->copies) | |
1273 | goto done; | |
1274 | ||
1275 | first = i; | |
1276 | fbio = r10_bio->devs[i].bio; | |
1277 | ||
1278 | /* now find blocks with errors */ | |
0eb3ff12 N |
1279 | for (i=0 ; i < conf->copies ; i++) { |
1280 | int j, d; | |
1281 | int vcnt = r10_bio->sectors >> (PAGE_SHIFT-9); | |
1da177e4 | 1282 | |
1da177e4 | 1283 | tbio = r10_bio->devs[i].bio; |
0eb3ff12 N |
1284 | |
1285 | if (tbio->bi_end_io != end_sync_read) | |
1286 | continue; | |
1287 | if (i == first) | |
1da177e4 | 1288 | continue; |
0eb3ff12 N |
1289 | if (test_bit(BIO_UPTODATE, &r10_bio->devs[i].bio->bi_flags)) { |
1290 | /* We know that the bi_io_vec layout is the same for | |
1291 | * both 'first' and 'i', so we just compare them. | |
1292 | * All vec entries are PAGE_SIZE; | |
1293 | */ | |
1294 | for (j = 0; j < vcnt; j++) | |
1295 | if (memcmp(page_address(fbio->bi_io_vec[j].bv_page), | |
1296 | page_address(tbio->bi_io_vec[j].bv_page), | |
1297 | PAGE_SIZE)) | |
1298 | break; | |
1299 | if (j == vcnt) | |
1300 | continue; | |
1301 | mddev->resync_mismatches += r10_bio->sectors; | |
1302 | } | |
18f08819 N |
1303 | if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)) |
1304 | /* Don't fix anything. */ | |
1305 | continue; | |
1da177e4 LT |
1306 | /* Ok, we need to write this bio |
1307 | * First we need to fixup bv_offset, bv_len and | |
1308 | * bi_vecs, as the read request might have corrupted these | |
1309 | */ | |
1310 | tbio->bi_vcnt = vcnt; | |
1311 | tbio->bi_size = r10_bio->sectors << 9; | |
1312 | tbio->bi_idx = 0; | |
1313 | tbio->bi_phys_segments = 0; | |
1da177e4 LT |
1314 | tbio->bi_flags &= ~(BIO_POOL_MASK - 1); |
1315 | tbio->bi_flags |= 1 << BIO_UPTODATE; | |
1316 | tbio->bi_next = NULL; | |
1317 | tbio->bi_rw = WRITE; | |
1318 | tbio->bi_private = r10_bio; | |
1319 | tbio->bi_sector = r10_bio->devs[i].addr; | |
1320 | ||
1321 | for (j=0; j < vcnt ; j++) { | |
1322 | tbio->bi_io_vec[j].bv_offset = 0; | |
1323 | tbio->bi_io_vec[j].bv_len = PAGE_SIZE; | |
1324 | ||
1325 | memcpy(page_address(tbio->bi_io_vec[j].bv_page), | |
1326 | page_address(fbio->bi_io_vec[j].bv_page), | |
1327 | PAGE_SIZE); | |
1328 | } | |
1329 | tbio->bi_end_io = end_sync_write; | |
1330 | ||
1331 | d = r10_bio->devs[i].devnum; | |
1332 | atomic_inc(&conf->mirrors[d].rdev->nr_pending); | |
1333 | atomic_inc(&r10_bio->remaining); | |
1334 | md_sync_acct(conf->mirrors[d].rdev->bdev, tbio->bi_size >> 9); | |
1335 | ||
1336 | tbio->bi_sector += conf->mirrors[d].rdev->data_offset; | |
1337 | tbio->bi_bdev = conf->mirrors[d].rdev->bdev; | |
1338 | generic_make_request(tbio); | |
1339 | } | |
1340 | ||
1341 | done: | |
1342 | if (atomic_dec_and_test(&r10_bio->remaining)) { | |
1343 | md_done_sync(mddev, r10_bio->sectors, 1); | |
1344 | put_buf(r10_bio); | |
1345 | } | |
1346 | } | |
1347 | ||
1348 | /* | |
1349 | * Now for the recovery code. | |
1350 | * Recovery happens across physical sectors. | |
1351 | * We recover all non-is_sync drives by finding the virtual address of | |
1352 | * each, and then choose a working drive that also has that virt address. | |
1353 | * There is a separate r10_bio for each non-in_sync drive. | |
1354 | * Only the first two slots are in use. The first for reading, | |
1355 | * The second for writing. | |
1356 | * | |
1357 | */ | |
1358 | ||
1359 | static void recovery_request_write(mddev_t *mddev, r10bio_t *r10_bio) | |
1360 | { | |
070ec55d | 1361 | conf_t *conf = mddev->private; |
1da177e4 LT |
1362 | int i, d; |
1363 | struct bio *bio, *wbio; | |
1364 | ||
1365 | ||
1366 | /* move the pages across to the second bio | |
1367 | * and submit the write request | |
1368 | */ | |
1369 | bio = r10_bio->devs[0].bio; | |
1370 | wbio = r10_bio->devs[1].bio; | |
1371 | for (i=0; i < wbio->bi_vcnt; i++) { | |
1372 | struct page *p = bio->bi_io_vec[i].bv_page; | |
1373 | bio->bi_io_vec[i].bv_page = wbio->bi_io_vec[i].bv_page; | |
1374 | wbio->bi_io_vec[i].bv_page = p; | |
1375 | } | |
1376 | d = r10_bio->devs[1].devnum; | |
1377 | ||
1378 | atomic_inc(&conf->mirrors[d].rdev->nr_pending); | |
1379 | md_sync_acct(conf->mirrors[d].rdev->bdev, wbio->bi_size >> 9); | |
0eb3ff12 N |
1380 | if (test_bit(R10BIO_Uptodate, &r10_bio->state)) |
1381 | generic_make_request(wbio); | |
1382 | else | |
6712ecf8 | 1383 | bio_endio(wbio, -EIO); |
1da177e4 LT |
1384 | } |
1385 | ||
1386 | ||
1e50915f RB |
1387 | /* |
1388 | * Used by fix_read_error() to decay the per rdev read_errors. | |
1389 | * We halve the read error count for every hour that has elapsed | |
1390 | * since the last recorded read error. | |
1391 | * | |
1392 | */ | |
1393 | static void check_decay_read_errors(mddev_t *mddev, mdk_rdev_t *rdev) | |
1394 | { | |
1395 | struct timespec cur_time_mon; | |
1396 | unsigned long hours_since_last; | |
1397 | unsigned int read_errors = atomic_read(&rdev->read_errors); | |
1398 | ||
1399 | ktime_get_ts(&cur_time_mon); | |
1400 | ||
1401 | if (rdev->last_read_error.tv_sec == 0 && | |
1402 | rdev->last_read_error.tv_nsec == 0) { | |
1403 | /* first time we've seen a read error */ | |
1404 | rdev->last_read_error = cur_time_mon; | |
1405 | return; | |
1406 | } | |
1407 | ||
1408 | hours_since_last = (cur_time_mon.tv_sec - | |
1409 | rdev->last_read_error.tv_sec) / 3600; | |
1410 | ||
1411 | rdev->last_read_error = cur_time_mon; | |
1412 | ||
1413 | /* | |
1414 | * if hours_since_last is > the number of bits in read_errors | |
1415 | * just set read errors to 0. We do this to avoid | |
1416 | * overflowing the shift of read_errors by hours_since_last. | |
1417 | */ | |
1418 | if (hours_since_last >= 8 * sizeof(read_errors)) | |
1419 | atomic_set(&rdev->read_errors, 0); | |
1420 | else | |
1421 | atomic_set(&rdev->read_errors, read_errors >> hours_since_last); | |
1422 | } | |
1423 | ||
1da177e4 LT |
1424 | /* |
1425 | * This is a kernel thread which: | |
1426 | * | |
1427 | * 1. Retries failed read operations on working mirrors. | |
1428 | * 2. Updates the raid superblock when problems encounter. | |
6814d536 | 1429 | * 3. Performs writes following reads for array synchronising. |
1da177e4 LT |
1430 | */ |
1431 | ||
6814d536 N |
1432 | static void fix_read_error(conf_t *conf, mddev_t *mddev, r10bio_t *r10_bio) |
1433 | { | |
1434 | int sect = 0; /* Offset from r10_bio->sector */ | |
1435 | int sectors = r10_bio->sectors; | |
1436 | mdk_rdev_t*rdev; | |
1e50915f | 1437 | int max_read_errors = atomic_read(&mddev->max_corr_read_errors); |
0544a21d | 1438 | int d = r10_bio->devs[r10_bio->read_slot].devnum; |
1e50915f | 1439 | |
7c4e06ff N |
1440 | /* still own a reference to this rdev, so it cannot |
1441 | * have been cleared recently. | |
1442 | */ | |
1443 | rdev = conf->mirrors[d].rdev; | |
1e50915f | 1444 | |
7c4e06ff N |
1445 | if (test_bit(Faulty, &rdev->flags)) |
1446 | /* drive has already been failed, just ignore any | |
1447 | more fix_read_error() attempts */ | |
1448 | return; | |
1e50915f | 1449 | |
7c4e06ff N |
1450 | check_decay_read_errors(mddev, rdev); |
1451 | atomic_inc(&rdev->read_errors); | |
1452 | if (atomic_read(&rdev->read_errors) > max_read_errors) { | |
1453 | char b[BDEVNAME_SIZE]; | |
1454 | bdevname(rdev->bdev, b); | |
1e50915f | 1455 | |
7c4e06ff N |
1456 | printk(KERN_NOTICE |
1457 | "md/raid10:%s: %s: Raid device exceeded " | |
1458 | "read_error threshold [cur %d:max %d]\n", | |
1459 | mdname(mddev), b, | |
1460 | atomic_read(&rdev->read_errors), max_read_errors); | |
1461 | printk(KERN_NOTICE | |
1462 | "md/raid10:%s: %s: Failing raid device\n", | |
1463 | mdname(mddev), b); | |
1464 | md_error(mddev, conf->mirrors[d].rdev); | |
1465 | return; | |
1e50915f | 1466 | } |
1e50915f | 1467 | |
6814d536 N |
1468 | while(sectors) { |
1469 | int s = sectors; | |
1470 | int sl = r10_bio->read_slot; | |
1471 | int success = 0; | |
1472 | int start; | |
1473 | ||
1474 | if (s > (PAGE_SIZE>>9)) | |
1475 | s = PAGE_SIZE >> 9; | |
1476 | ||
1477 | rcu_read_lock(); | |
1478 | do { | |
0544a21d | 1479 | d = r10_bio->devs[sl].devnum; |
6814d536 N |
1480 | rdev = rcu_dereference(conf->mirrors[d].rdev); |
1481 | if (rdev && | |
1482 | test_bit(In_sync, &rdev->flags)) { | |
1483 | atomic_inc(&rdev->nr_pending); | |
1484 | rcu_read_unlock(); | |
2b193363 | 1485 | success = sync_page_io(rdev, |
6814d536 | 1486 | r10_bio->devs[sl].addr + |
ccebd4c4 | 1487 | sect, |
6814d536 | 1488 | s<<9, |
ccebd4c4 | 1489 | conf->tmppage, READ, false); |
6814d536 N |
1490 | rdev_dec_pending(rdev, mddev); |
1491 | rcu_read_lock(); | |
1492 | if (success) | |
1493 | break; | |
1494 | } | |
1495 | sl++; | |
1496 | if (sl == conf->copies) | |
1497 | sl = 0; | |
1498 | } while (!success && sl != r10_bio->read_slot); | |
1499 | rcu_read_unlock(); | |
1500 | ||
1501 | if (!success) { | |
1502 | /* Cannot read from anywhere -- bye bye array */ | |
1503 | int dn = r10_bio->devs[r10_bio->read_slot].devnum; | |
1504 | md_error(mddev, conf->mirrors[dn].rdev); | |
1505 | break; | |
1506 | } | |
1507 | ||
1508 | start = sl; | |
1509 | /* write it back and re-read */ | |
1510 | rcu_read_lock(); | |
1511 | while (sl != r10_bio->read_slot) { | |
67b8dc4b | 1512 | char b[BDEVNAME_SIZE]; |
0544a21d | 1513 | |
6814d536 N |
1514 | if (sl==0) |
1515 | sl = conf->copies; | |
1516 | sl--; | |
1517 | d = r10_bio->devs[sl].devnum; | |
1518 | rdev = rcu_dereference(conf->mirrors[d].rdev); | |
1519 | if (rdev && | |
1520 | test_bit(In_sync, &rdev->flags)) { | |
1521 | atomic_inc(&rdev->nr_pending); | |
1522 | rcu_read_unlock(); | |
1523 | atomic_add(s, &rdev->corrected_errors); | |
2b193363 | 1524 | if (sync_page_io(rdev, |
6814d536 | 1525 | r10_bio->devs[sl].addr + |
ccebd4c4 JB |
1526 | sect, |
1527 | s<<9, conf->tmppage, WRITE, false) | |
67b8dc4b | 1528 | == 0) { |
6814d536 | 1529 | /* Well, this device is dead */ |
67b8dc4b | 1530 | printk(KERN_NOTICE |
128595ed | 1531 | "md/raid10:%s: read correction " |
67b8dc4b RB |
1532 | "write failed" |
1533 | " (%d sectors at %llu on %s)\n", | |
1534 | mdname(mddev), s, | |
7c4e06ff N |
1535 | (unsigned long long)( |
1536 | sect + rdev->data_offset), | |
67b8dc4b | 1537 | bdevname(rdev->bdev, b)); |
128595ed | 1538 | printk(KERN_NOTICE "md/raid10:%s: %s: failing " |
67b8dc4b | 1539 | "drive\n", |
128595ed | 1540 | mdname(mddev), |
67b8dc4b | 1541 | bdevname(rdev->bdev, b)); |
6814d536 | 1542 | md_error(mddev, rdev); |
67b8dc4b | 1543 | } |
6814d536 N |
1544 | rdev_dec_pending(rdev, mddev); |
1545 | rcu_read_lock(); | |
1546 | } | |
1547 | } | |
1548 | sl = start; | |
1549 | while (sl != r10_bio->read_slot) { | |
0544a21d | 1550 | |
6814d536 N |
1551 | if (sl==0) |
1552 | sl = conf->copies; | |
1553 | sl--; | |
1554 | d = r10_bio->devs[sl].devnum; | |
1555 | rdev = rcu_dereference(conf->mirrors[d].rdev); | |
1556 | if (rdev && | |
1557 | test_bit(In_sync, &rdev->flags)) { | |
1558 | char b[BDEVNAME_SIZE]; | |
1559 | atomic_inc(&rdev->nr_pending); | |
1560 | rcu_read_unlock(); | |
2b193363 | 1561 | if (sync_page_io(rdev, |
6814d536 | 1562 | r10_bio->devs[sl].addr + |
ccebd4c4 | 1563 | sect, |
67b8dc4b | 1564 | s<<9, conf->tmppage, |
ccebd4c4 | 1565 | READ, false) == 0) { |
6814d536 | 1566 | /* Well, this device is dead */ |
67b8dc4b | 1567 | printk(KERN_NOTICE |
128595ed | 1568 | "md/raid10:%s: unable to read back " |
67b8dc4b RB |
1569 | "corrected sectors" |
1570 | " (%d sectors at %llu on %s)\n", | |
1571 | mdname(mddev), s, | |
7c4e06ff N |
1572 | (unsigned long long)( |
1573 | sect + rdev->data_offset), | |
67b8dc4b | 1574 | bdevname(rdev->bdev, b)); |
128595ed N |
1575 | printk(KERN_NOTICE "md/raid10:%s: %s: failing drive\n", |
1576 | mdname(mddev), | |
67b8dc4b RB |
1577 | bdevname(rdev->bdev, b)); |
1578 | ||
6814d536 | 1579 | md_error(mddev, rdev); |
67b8dc4b | 1580 | } else { |
6814d536 | 1581 | printk(KERN_INFO |
128595ed | 1582 | "md/raid10:%s: read error corrected" |
6814d536 N |
1583 | " (%d sectors at %llu on %s)\n", |
1584 | mdname(mddev), s, | |
7c4e06ff N |
1585 | (unsigned long long)( |
1586 | sect + rdev->data_offset), | |
6814d536 | 1587 | bdevname(rdev->bdev, b)); |
67b8dc4b | 1588 | } |
6814d536 N |
1589 | |
1590 | rdev_dec_pending(rdev, mddev); | |
1591 | rcu_read_lock(); | |
1592 | } | |
1593 | } | |
1594 | rcu_read_unlock(); | |
1595 | ||
1596 | sectors -= s; | |
1597 | sect += s; | |
1598 | } | |
1599 | } | |
1600 | ||
1da177e4 LT |
1601 | static void raid10d(mddev_t *mddev) |
1602 | { | |
1603 | r10bio_t *r10_bio; | |
1604 | struct bio *bio; | |
1605 | unsigned long flags; | |
070ec55d | 1606 | conf_t *conf = mddev->private; |
1da177e4 | 1607 | struct list_head *head = &conf->retry_list; |
1da177e4 | 1608 | mdk_rdev_t *rdev; |
e1dfa0a2 | 1609 | struct blk_plug plug; |
1da177e4 LT |
1610 | |
1611 | md_check_recovery(mddev); | |
1da177e4 | 1612 | |
e1dfa0a2 | 1613 | blk_start_plug(&plug); |
1da177e4 LT |
1614 | for (;;) { |
1615 | char b[BDEVNAME_SIZE]; | |
6cce3b23 | 1616 | |
7eaceacc | 1617 | flush_pending_writes(conf); |
6cce3b23 | 1618 | |
a35e63ef N |
1619 | spin_lock_irqsave(&conf->device_lock, flags); |
1620 | if (list_empty(head)) { | |
1621 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
1da177e4 | 1622 | break; |
a35e63ef | 1623 | } |
1da177e4 LT |
1624 | r10_bio = list_entry(head->prev, r10bio_t, retry_list); |
1625 | list_del(head->prev); | |
4443ae10 | 1626 | conf->nr_queued--; |
1da177e4 LT |
1627 | spin_unlock_irqrestore(&conf->device_lock, flags); |
1628 | ||
1629 | mddev = r10_bio->mddev; | |
070ec55d | 1630 | conf = mddev->private; |
7eaceacc | 1631 | if (test_bit(R10BIO_IsSync, &r10_bio->state)) |
1da177e4 | 1632 | sync_request_write(mddev, r10_bio); |
7eaceacc | 1633 | else if (test_bit(R10BIO_IsRecover, &r10_bio->state)) |
1da177e4 | 1634 | recovery_request_write(mddev, r10_bio); |
7eaceacc | 1635 | else { |
7c4e06ff N |
1636 | int slot = r10_bio->read_slot; |
1637 | int mirror = r10_bio->devs[slot].devnum; | |
4443ae10 N |
1638 | /* we got a read error. Maybe the drive is bad. Maybe just |
1639 | * the block and we can fix it. | |
1640 | * We freeze all other IO, and try reading the block from | |
1641 | * other devices. When we find one, we re-write | |
1642 | * and check it that fixes the read error. | |
1643 | * This is all done synchronously while the array is | |
1644 | * frozen. | |
1645 | */ | |
6814d536 N |
1646 | if (mddev->ro == 0) { |
1647 | freeze_array(conf); | |
1648 | fix_read_error(conf, mddev, r10_bio); | |
1649 | unfreeze_array(conf); | |
4443ae10 | 1650 | } |
7c4e06ff | 1651 | rdev_dec_pending(conf->mirrors[mirror].rdev, mddev); |
4443ae10 | 1652 | |
a8830bca N |
1653 | bio = r10_bio->devs[slot].bio; |
1654 | r10_bio->devs[slot].bio = | |
0eb3ff12 | 1655 | mddev->ro ? IO_BLOCKED : NULL; |
1da177e4 LT |
1656 | mirror = read_balance(conf, r10_bio); |
1657 | if (mirror == -1) { | |
128595ed | 1658 | printk(KERN_ALERT "md/raid10:%s: %s: unrecoverable I/O" |
1da177e4 | 1659 | " read error for block %llu\n", |
128595ed | 1660 | mdname(mddev), |
1da177e4 LT |
1661 | bdevname(bio->bi_bdev,b), |
1662 | (unsigned long long)r10_bio->sector); | |
1663 | raid_end_bio_io(r10_bio); | |
14e71344 | 1664 | bio_put(bio); |
1da177e4 | 1665 | } else { |
2c7d46ec | 1666 | const unsigned long do_sync = (r10_bio->master_bio->bi_rw & REQ_SYNC); |
14e71344 | 1667 | bio_put(bio); |
a8830bca | 1668 | slot = r10_bio->read_slot; |
1da177e4 LT |
1669 | rdev = conf->mirrors[mirror].rdev; |
1670 | if (printk_ratelimit()) | |
128595ed | 1671 | printk(KERN_ERR "md/raid10:%s: %s: redirecting sector %llu to" |
1da177e4 | 1672 | " another mirror\n", |
128595ed | 1673 | mdname(mddev), |
1da177e4 LT |
1674 | bdevname(rdev->bdev,b), |
1675 | (unsigned long long)r10_bio->sector); | |
a167f663 N |
1676 | bio = bio_clone_mddev(r10_bio->master_bio, |
1677 | GFP_NOIO, mddev); | |
a8830bca N |
1678 | r10_bio->devs[slot].bio = bio; |
1679 | bio->bi_sector = r10_bio->devs[slot].addr | |
1da177e4 LT |
1680 | + rdev->data_offset; |
1681 | bio->bi_bdev = rdev->bdev; | |
7b6d91da | 1682 | bio->bi_rw = READ | do_sync; |
1da177e4 LT |
1683 | bio->bi_private = r10_bio; |
1684 | bio->bi_end_io = raid10_end_read_request; | |
1da177e4 LT |
1685 | generic_make_request(bio); |
1686 | } | |
1687 | } | |
1d9d5241 | 1688 | cond_resched(); |
1da177e4 | 1689 | } |
e1dfa0a2 | 1690 | blk_finish_plug(&plug); |
1da177e4 LT |
1691 | } |
1692 | ||
1693 | ||
1694 | static int init_resync(conf_t *conf) | |
1695 | { | |
1696 | int buffs; | |
1697 | ||
1698 | buffs = RESYNC_WINDOW / RESYNC_BLOCK_SIZE; | |
b6385483 | 1699 | BUG_ON(conf->r10buf_pool); |
1da177e4 LT |
1700 | conf->r10buf_pool = mempool_create(buffs, r10buf_pool_alloc, r10buf_pool_free, conf); |
1701 | if (!conf->r10buf_pool) | |
1702 | return -ENOMEM; | |
1703 | conf->next_resync = 0; | |
1704 | return 0; | |
1705 | } | |
1706 | ||
1707 | /* | |
1708 | * perform a "sync" on one "block" | |
1709 | * | |
1710 | * We need to make sure that no normal I/O request - particularly write | |
1711 | * requests - conflict with active sync requests. | |
1712 | * | |
1713 | * This is achieved by tracking pending requests and a 'barrier' concept | |
1714 | * that can be installed to exclude normal IO requests. | |
1715 | * | |
1716 | * Resync and recovery are handled very differently. | |
1717 | * We differentiate by looking at MD_RECOVERY_SYNC in mddev->recovery. | |
1718 | * | |
1719 | * For resync, we iterate over virtual addresses, read all copies, | |
1720 | * and update if there are differences. If only one copy is live, | |
1721 | * skip it. | |
1722 | * For recovery, we iterate over physical addresses, read a good | |
1723 | * value for each non-in_sync drive, and over-write. | |
1724 | * | |
1725 | * So, for recovery we may have several outstanding complex requests for a | |
1726 | * given address, one for each out-of-sync device. We model this by allocating | |
1727 | * a number of r10_bio structures, one for each out-of-sync device. | |
1728 | * As we setup these structures, we collect all bio's together into a list | |
1729 | * which we then process collectively to add pages, and then process again | |
1730 | * to pass to generic_make_request. | |
1731 | * | |
1732 | * The r10_bio structures are linked using a borrowed master_bio pointer. | |
1733 | * This link is counted in ->remaining. When the r10_bio that points to NULL | |
1734 | * has its remaining count decremented to 0, the whole complex operation | |
1735 | * is complete. | |
1736 | * | |
1737 | */ | |
1738 | ||
ab9d47e9 N |
1739 | static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, |
1740 | int *skipped, int go_faster) | |
1da177e4 | 1741 | { |
070ec55d | 1742 | conf_t *conf = mddev->private; |
1da177e4 LT |
1743 | r10bio_t *r10_bio; |
1744 | struct bio *biolist = NULL, *bio; | |
1745 | sector_t max_sector, nr_sectors; | |
1da177e4 | 1746 | int i; |
6cce3b23 | 1747 | int max_sync; |
57dab0bd | 1748 | sector_t sync_blocks; |
1da177e4 LT |
1749 | |
1750 | sector_t sectors_skipped = 0; | |
1751 | int chunks_skipped = 0; | |
1752 | ||
1753 | if (!conf->r10buf_pool) | |
1754 | if (init_resync(conf)) | |
57afd89f | 1755 | return 0; |
1da177e4 LT |
1756 | |
1757 | skipped: | |
58c0fed4 | 1758 | max_sector = mddev->dev_sectors; |
1da177e4 LT |
1759 | if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) |
1760 | max_sector = mddev->resync_max_sectors; | |
1761 | if (sector_nr >= max_sector) { | |
6cce3b23 N |
1762 | /* If we aborted, we need to abort the |
1763 | * sync on the 'current' bitmap chucks (there can | |
1764 | * be several when recovering multiple devices). | |
1765 | * as we may have started syncing it but not finished. | |
1766 | * We can find the current address in | |
1767 | * mddev->curr_resync, but for recovery, | |
1768 | * we need to convert that to several | |
1769 | * virtual addresses. | |
1770 | */ | |
1771 | if (mddev->curr_resync < max_sector) { /* aborted */ | |
1772 | if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) | |
1773 | bitmap_end_sync(mddev->bitmap, mddev->curr_resync, | |
1774 | &sync_blocks, 1); | |
1775 | else for (i=0; i<conf->raid_disks; i++) { | |
1776 | sector_t sect = | |
1777 | raid10_find_virt(conf, mddev->curr_resync, i); | |
1778 | bitmap_end_sync(mddev->bitmap, sect, | |
1779 | &sync_blocks, 1); | |
1780 | } | |
1781 | } else /* completed sync */ | |
1782 | conf->fullsync = 0; | |
1783 | ||
1784 | bitmap_close_sync(mddev->bitmap); | |
1da177e4 | 1785 | close_sync(conf); |
57afd89f | 1786 | *skipped = 1; |
1da177e4 LT |
1787 | return sectors_skipped; |
1788 | } | |
1789 | if (chunks_skipped >= conf->raid_disks) { | |
1790 | /* if there has been nothing to do on any drive, | |
1791 | * then there is nothing to do at all.. | |
1792 | */ | |
57afd89f N |
1793 | *skipped = 1; |
1794 | return (max_sector - sector_nr) + sectors_skipped; | |
1da177e4 LT |
1795 | } |
1796 | ||
c6207277 N |
1797 | if (max_sector > mddev->resync_max) |
1798 | max_sector = mddev->resync_max; /* Don't do IO beyond here */ | |
1799 | ||
1da177e4 LT |
1800 | /* make sure whole request will fit in a chunk - if chunks |
1801 | * are meaningful | |
1802 | */ | |
1803 | if (conf->near_copies < conf->raid_disks && | |
1804 | max_sector > (sector_nr | conf->chunk_mask)) | |
1805 | max_sector = (sector_nr | conf->chunk_mask) + 1; | |
1806 | /* | |
1807 | * If there is non-resync activity waiting for us then | |
1808 | * put in a delay to throttle resync. | |
1809 | */ | |
0a27ec96 | 1810 | if (!go_faster && conf->nr_waiting) |
1da177e4 | 1811 | msleep_interruptible(1000); |
1da177e4 LT |
1812 | |
1813 | /* Again, very different code for resync and recovery. | |
1814 | * Both must result in an r10bio with a list of bios that | |
1815 | * have bi_end_io, bi_sector, bi_bdev set, | |
1816 | * and bi_private set to the r10bio. | |
1817 | * For recovery, we may actually create several r10bios | |
1818 | * with 2 bios in each, that correspond to the bios in the main one. | |
1819 | * In this case, the subordinate r10bios link back through a | |
1820 | * borrowed master_bio pointer, and the counter in the master | |
1821 | * includes a ref from each subordinate. | |
1822 | */ | |
1823 | /* First, we decide what to do and set ->bi_end_io | |
1824 | * To end_sync_read if we want to read, and | |
1825 | * end_sync_write if we will want to write. | |
1826 | */ | |
1827 | ||
6cce3b23 | 1828 | max_sync = RESYNC_PAGES << (PAGE_SHIFT-9); |
1da177e4 LT |
1829 | if (!test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) { |
1830 | /* recovery... the complicated one */ | |
a9f326eb | 1831 | int j, k; |
1da177e4 LT |
1832 | r10_bio = NULL; |
1833 | ||
ab9d47e9 N |
1834 | for (i=0 ; i<conf->raid_disks; i++) { |
1835 | int still_degraded; | |
1836 | r10bio_t *rb2; | |
1837 | sector_t sect; | |
1838 | int must_sync; | |
1da177e4 | 1839 | |
ab9d47e9 N |
1840 | if (conf->mirrors[i].rdev == NULL || |
1841 | test_bit(In_sync, &conf->mirrors[i].rdev->flags)) | |
1842 | continue; | |
1da177e4 | 1843 | |
ab9d47e9 N |
1844 | still_degraded = 0; |
1845 | /* want to reconstruct this device */ | |
1846 | rb2 = r10_bio; | |
1847 | sect = raid10_find_virt(conf, sector_nr, i); | |
1848 | /* Unless we are doing a full sync, we only need | |
1849 | * to recover the block if it is set in the bitmap | |
1850 | */ | |
1851 | must_sync = bitmap_start_sync(mddev->bitmap, sect, | |
1852 | &sync_blocks, 1); | |
1853 | if (sync_blocks < max_sync) | |
1854 | max_sync = sync_blocks; | |
1855 | if (!must_sync && | |
1856 | !conf->fullsync) { | |
1857 | /* yep, skip the sync_blocks here, but don't assume | |
1858 | * that there will never be anything to do here | |
1859 | */ | |
1860 | chunks_skipped = -1; | |
1861 | continue; | |
1862 | } | |
6cce3b23 | 1863 | |
ab9d47e9 N |
1864 | r10_bio = mempool_alloc(conf->r10buf_pool, GFP_NOIO); |
1865 | raise_barrier(conf, rb2 != NULL); | |
1866 | atomic_set(&r10_bio->remaining, 0); | |
18055569 | 1867 | |
ab9d47e9 N |
1868 | r10_bio->master_bio = (struct bio*)rb2; |
1869 | if (rb2) | |
1870 | atomic_inc(&rb2->remaining); | |
1871 | r10_bio->mddev = mddev; | |
1872 | set_bit(R10BIO_IsRecover, &r10_bio->state); | |
1873 | r10_bio->sector = sect; | |
1da177e4 | 1874 | |
ab9d47e9 N |
1875 | raid10_find_phys(conf, r10_bio); |
1876 | ||
1877 | /* Need to check if the array will still be | |
1878 | * degraded | |
1879 | */ | |
1880 | for (j=0; j<conf->raid_disks; j++) | |
1881 | if (conf->mirrors[j].rdev == NULL || | |
1882 | test_bit(Faulty, &conf->mirrors[j].rdev->flags)) { | |
1883 | still_degraded = 1; | |
87fc767b | 1884 | break; |
1da177e4 | 1885 | } |
ab9d47e9 N |
1886 | |
1887 | must_sync = bitmap_start_sync(mddev->bitmap, sect, | |
1888 | &sync_blocks, still_degraded); | |
1889 | ||
1890 | for (j=0; j<conf->copies;j++) { | |
1891 | int d = r10_bio->devs[j].devnum; | |
1892 | if (!conf->mirrors[d].rdev || | |
1893 | !test_bit(In_sync, &conf->mirrors[d].rdev->flags)) | |
1894 | continue; | |
1895 | /* This is where we read from */ | |
1896 | bio = r10_bio->devs[0].bio; | |
1897 | bio->bi_next = biolist; | |
1898 | biolist = bio; | |
1899 | bio->bi_private = r10_bio; | |
1900 | bio->bi_end_io = end_sync_read; | |
1901 | bio->bi_rw = READ; | |
1902 | bio->bi_sector = r10_bio->devs[j].addr + | |
1903 | conf->mirrors[d].rdev->data_offset; | |
1904 | bio->bi_bdev = conf->mirrors[d].rdev->bdev; | |
1905 | atomic_inc(&conf->mirrors[d].rdev->nr_pending); | |
1906 | atomic_inc(&r10_bio->remaining); | |
1907 | /* and we write to 'i' */ | |
1908 | ||
1909 | for (k=0; k<conf->copies; k++) | |
1910 | if (r10_bio->devs[k].devnum == i) | |
1911 | break; | |
1912 | BUG_ON(k == conf->copies); | |
1913 | bio = r10_bio->devs[1].bio; | |
1914 | bio->bi_next = biolist; | |
1915 | biolist = bio; | |
1916 | bio->bi_private = r10_bio; | |
1917 | bio->bi_end_io = end_sync_write; | |
1918 | bio->bi_rw = WRITE; | |
1919 | bio->bi_sector = r10_bio->devs[k].addr + | |
1920 | conf->mirrors[i].rdev->data_offset; | |
1921 | bio->bi_bdev = conf->mirrors[i].rdev->bdev; | |
1922 | ||
1923 | r10_bio->devs[0].devnum = d; | |
1924 | r10_bio->devs[1].devnum = i; | |
1925 | ||
1926 | break; | |
1927 | } | |
1928 | if (j == conf->copies) { | |
1929 | /* Cannot recover, so abort the recovery */ | |
1930 | put_buf(r10_bio); | |
1931 | if (rb2) | |
1932 | atomic_dec(&rb2->remaining); | |
1933 | r10_bio = rb2; | |
1934 | if (!test_and_set_bit(MD_RECOVERY_INTR, | |
1935 | &mddev->recovery)) | |
1936 | printk(KERN_INFO "md/raid10:%s: insufficient " | |
1937 | "working devices for recovery.\n", | |
1938 | mdname(mddev)); | |
1939 | break; | |
1da177e4 | 1940 | } |
ab9d47e9 | 1941 | } |
1da177e4 LT |
1942 | if (biolist == NULL) { |
1943 | while (r10_bio) { | |
1944 | r10bio_t *rb2 = r10_bio; | |
1945 | r10_bio = (r10bio_t*) rb2->master_bio; | |
1946 | rb2->master_bio = NULL; | |
1947 | put_buf(rb2); | |
1948 | } | |
1949 | goto giveup; | |
1950 | } | |
1951 | } else { | |
1952 | /* resync. Schedule a read for every block at this virt offset */ | |
1953 | int count = 0; | |
6cce3b23 | 1954 | |
78200d45 N |
1955 | bitmap_cond_end_sync(mddev->bitmap, sector_nr); |
1956 | ||
6cce3b23 N |
1957 | if (!bitmap_start_sync(mddev->bitmap, sector_nr, |
1958 | &sync_blocks, mddev->degraded) && | |
ab9d47e9 N |
1959 | !conf->fullsync && !test_bit(MD_RECOVERY_REQUESTED, |
1960 | &mddev->recovery)) { | |
6cce3b23 N |
1961 | /* We can skip this block */ |
1962 | *skipped = 1; | |
1963 | return sync_blocks + sectors_skipped; | |
1964 | } | |
1965 | if (sync_blocks < max_sync) | |
1966 | max_sync = sync_blocks; | |
1da177e4 LT |
1967 | r10_bio = mempool_alloc(conf->r10buf_pool, GFP_NOIO); |
1968 | ||
1da177e4 LT |
1969 | r10_bio->mddev = mddev; |
1970 | atomic_set(&r10_bio->remaining, 0); | |
6cce3b23 N |
1971 | raise_barrier(conf, 0); |
1972 | conf->next_resync = sector_nr; | |
1da177e4 LT |
1973 | |
1974 | r10_bio->master_bio = NULL; | |
1975 | r10_bio->sector = sector_nr; | |
1976 | set_bit(R10BIO_IsSync, &r10_bio->state); | |
1977 | raid10_find_phys(conf, r10_bio); | |
1978 | r10_bio->sectors = (sector_nr | conf->chunk_mask) - sector_nr +1; | |
1979 | ||
1980 | for (i=0; i<conf->copies; i++) { | |
1981 | int d = r10_bio->devs[i].devnum; | |
1982 | bio = r10_bio->devs[i].bio; | |
1983 | bio->bi_end_io = NULL; | |
af03b8e4 | 1984 | clear_bit(BIO_UPTODATE, &bio->bi_flags); |
1da177e4 | 1985 | if (conf->mirrors[d].rdev == NULL || |
b2d444d7 | 1986 | test_bit(Faulty, &conf->mirrors[d].rdev->flags)) |
1da177e4 LT |
1987 | continue; |
1988 | atomic_inc(&conf->mirrors[d].rdev->nr_pending); | |
1989 | atomic_inc(&r10_bio->remaining); | |
1990 | bio->bi_next = biolist; | |
1991 | biolist = bio; | |
1992 | bio->bi_private = r10_bio; | |
1993 | bio->bi_end_io = end_sync_read; | |
802ba064 | 1994 | bio->bi_rw = READ; |
1da177e4 LT |
1995 | bio->bi_sector = r10_bio->devs[i].addr + |
1996 | conf->mirrors[d].rdev->data_offset; | |
1997 | bio->bi_bdev = conf->mirrors[d].rdev->bdev; | |
1998 | count++; | |
1999 | } | |
2000 | ||
2001 | if (count < 2) { | |
2002 | for (i=0; i<conf->copies; i++) { | |
2003 | int d = r10_bio->devs[i].devnum; | |
2004 | if (r10_bio->devs[i].bio->bi_end_io) | |
ab9d47e9 N |
2005 | rdev_dec_pending(conf->mirrors[d].rdev, |
2006 | mddev); | |
1da177e4 LT |
2007 | } |
2008 | put_buf(r10_bio); | |
2009 | biolist = NULL; | |
2010 | goto giveup; | |
2011 | } | |
2012 | } | |
2013 | ||
2014 | for (bio = biolist; bio ; bio=bio->bi_next) { | |
2015 | ||
2016 | bio->bi_flags &= ~(BIO_POOL_MASK - 1); | |
2017 | if (bio->bi_end_io) | |
2018 | bio->bi_flags |= 1 << BIO_UPTODATE; | |
2019 | bio->bi_vcnt = 0; | |
2020 | bio->bi_idx = 0; | |
2021 | bio->bi_phys_segments = 0; | |
1da177e4 LT |
2022 | bio->bi_size = 0; |
2023 | } | |
2024 | ||
2025 | nr_sectors = 0; | |
6cce3b23 N |
2026 | if (sector_nr + max_sync < max_sector) |
2027 | max_sector = sector_nr + max_sync; | |
1da177e4 LT |
2028 | do { |
2029 | struct page *page; | |
2030 | int len = PAGE_SIZE; | |
1da177e4 LT |
2031 | if (sector_nr + (len>>9) > max_sector) |
2032 | len = (max_sector - sector_nr) << 9; | |
2033 | if (len == 0) | |
2034 | break; | |
2035 | for (bio= biolist ; bio ; bio=bio->bi_next) { | |
ab9d47e9 | 2036 | struct bio *bio2; |
1da177e4 | 2037 | page = bio->bi_io_vec[bio->bi_vcnt].bv_page; |
ab9d47e9 N |
2038 | if (bio_add_page(bio, page, len, 0)) |
2039 | continue; | |
2040 | ||
2041 | /* stop here */ | |
2042 | bio->bi_io_vec[bio->bi_vcnt].bv_page = page; | |
2043 | for (bio2 = biolist; | |
2044 | bio2 && bio2 != bio; | |
2045 | bio2 = bio2->bi_next) { | |
2046 | /* remove last page from this bio */ | |
2047 | bio2->bi_vcnt--; | |
2048 | bio2->bi_size -= len; | |
2049 | bio2->bi_flags &= ~(1<< BIO_SEG_VALID); | |
1da177e4 | 2050 | } |
ab9d47e9 | 2051 | goto bio_full; |
1da177e4 LT |
2052 | } |
2053 | nr_sectors += len>>9; | |
2054 | sector_nr += len>>9; | |
2055 | } while (biolist->bi_vcnt < RESYNC_PAGES); | |
2056 | bio_full: | |
2057 | r10_bio->sectors = nr_sectors; | |
2058 | ||
2059 | while (biolist) { | |
2060 | bio = biolist; | |
2061 | biolist = biolist->bi_next; | |
2062 | ||
2063 | bio->bi_next = NULL; | |
2064 | r10_bio = bio->bi_private; | |
2065 | r10_bio->sectors = nr_sectors; | |
2066 | ||
2067 | if (bio->bi_end_io == end_sync_read) { | |
2068 | md_sync_acct(bio->bi_bdev, nr_sectors); | |
2069 | generic_make_request(bio); | |
2070 | } | |
2071 | } | |
2072 | ||
57afd89f N |
2073 | if (sectors_skipped) |
2074 | /* pretend they weren't skipped, it makes | |
2075 | * no important difference in this case | |
2076 | */ | |
2077 | md_done_sync(mddev, sectors_skipped, 1); | |
2078 | ||
1da177e4 LT |
2079 | return sectors_skipped + nr_sectors; |
2080 | giveup: | |
2081 | /* There is nowhere to write, so all non-sync | |
2082 | * drives must be failed, so try the next chunk... | |
2083 | */ | |
09b4068a N |
2084 | if (sector_nr + max_sync < max_sector) |
2085 | max_sector = sector_nr + max_sync; | |
2086 | ||
2087 | sectors_skipped += (max_sector - sector_nr); | |
1da177e4 LT |
2088 | chunks_skipped ++; |
2089 | sector_nr = max_sector; | |
1da177e4 | 2090 | goto skipped; |
1da177e4 LT |
2091 | } |
2092 | ||
80c3a6ce DW |
2093 | static sector_t |
2094 | raid10_size(mddev_t *mddev, sector_t sectors, int raid_disks) | |
2095 | { | |
2096 | sector_t size; | |
070ec55d | 2097 | conf_t *conf = mddev->private; |
80c3a6ce DW |
2098 | |
2099 | if (!raid_disks) | |
84707f38 | 2100 | raid_disks = conf->raid_disks; |
80c3a6ce | 2101 | if (!sectors) |
dab8b292 | 2102 | sectors = conf->dev_sectors; |
80c3a6ce DW |
2103 | |
2104 | size = sectors >> conf->chunk_shift; | |
2105 | sector_div(size, conf->far_copies); | |
2106 | size = size * raid_disks; | |
2107 | sector_div(size, conf->near_copies); | |
2108 | ||
2109 | return size << conf->chunk_shift; | |
2110 | } | |
2111 | ||
dab8b292 TM |
2112 | |
2113 | static conf_t *setup_conf(mddev_t *mddev) | |
1da177e4 | 2114 | { |
dab8b292 | 2115 | conf_t *conf = NULL; |
c93983bf | 2116 | int nc, fc, fo; |
1da177e4 | 2117 | sector_t stride, size; |
dab8b292 | 2118 | int err = -EINVAL; |
1da177e4 | 2119 | |
f73ea873 MT |
2120 | if (mddev->new_chunk_sectors < (PAGE_SIZE >> 9) || |
2121 | !is_power_of_2(mddev->new_chunk_sectors)) { | |
128595ed N |
2122 | printk(KERN_ERR "md/raid10:%s: chunk size must be " |
2123 | "at least PAGE_SIZE(%ld) and be a power of 2.\n", | |
2124 | mdname(mddev), PAGE_SIZE); | |
dab8b292 | 2125 | goto out; |
1da177e4 | 2126 | } |
2604b703 | 2127 | |
f73ea873 MT |
2128 | nc = mddev->new_layout & 255; |
2129 | fc = (mddev->new_layout >> 8) & 255; | |
2130 | fo = mddev->new_layout & (1<<16); | |
dab8b292 | 2131 | |
1da177e4 | 2132 | if ((nc*fc) <2 || (nc*fc) > mddev->raid_disks || |
f73ea873 | 2133 | (mddev->new_layout >> 17)) { |
128595ed | 2134 | printk(KERN_ERR "md/raid10:%s: unsupported raid10 layout: 0x%8x\n", |
f73ea873 | 2135 | mdname(mddev), mddev->new_layout); |
1da177e4 LT |
2136 | goto out; |
2137 | } | |
dab8b292 TM |
2138 | |
2139 | err = -ENOMEM; | |
4443ae10 | 2140 | conf = kzalloc(sizeof(conf_t), GFP_KERNEL); |
dab8b292 | 2141 | if (!conf) |
1da177e4 | 2142 | goto out; |
dab8b292 | 2143 | |
4443ae10 | 2144 | conf->mirrors = kzalloc(sizeof(struct mirror_info)*mddev->raid_disks, |
dab8b292 TM |
2145 | GFP_KERNEL); |
2146 | if (!conf->mirrors) | |
2147 | goto out; | |
4443ae10 N |
2148 | |
2149 | conf->tmppage = alloc_page(GFP_KERNEL); | |
2150 | if (!conf->tmppage) | |
dab8b292 TM |
2151 | goto out; |
2152 | ||
1da177e4 | 2153 | |
64a742bc | 2154 | conf->raid_disks = mddev->raid_disks; |
1da177e4 LT |
2155 | conf->near_copies = nc; |
2156 | conf->far_copies = fc; | |
2157 | conf->copies = nc*fc; | |
c93983bf | 2158 | conf->far_offset = fo; |
dab8b292 TM |
2159 | conf->chunk_mask = mddev->new_chunk_sectors - 1; |
2160 | conf->chunk_shift = ffz(~mddev->new_chunk_sectors); | |
2161 | ||
2162 | conf->r10bio_pool = mempool_create(NR_RAID10_BIOS, r10bio_pool_alloc, | |
2163 | r10bio_pool_free, conf); | |
2164 | if (!conf->r10bio_pool) | |
2165 | goto out; | |
2166 | ||
58c0fed4 | 2167 | size = mddev->dev_sectors >> conf->chunk_shift; |
64a742bc N |
2168 | sector_div(size, fc); |
2169 | size = size * conf->raid_disks; | |
2170 | sector_div(size, nc); | |
2171 | /* 'size' is now the number of chunks in the array */ | |
2172 | /* calculate "used chunks per device" in 'stride' */ | |
2173 | stride = size * conf->copies; | |
af03b8e4 N |
2174 | |
2175 | /* We need to round up when dividing by raid_disks to | |
2176 | * get the stride size. | |
2177 | */ | |
2178 | stride += conf->raid_disks - 1; | |
64a742bc | 2179 | sector_div(stride, conf->raid_disks); |
dab8b292 TM |
2180 | |
2181 | conf->dev_sectors = stride << conf->chunk_shift; | |
64a742bc | 2182 | |
c93983bf | 2183 | if (fo) |
64a742bc N |
2184 | stride = 1; |
2185 | else | |
c93983bf | 2186 | sector_div(stride, fc); |
64a742bc N |
2187 | conf->stride = stride << conf->chunk_shift; |
2188 | ||
1da177e4 | 2189 | |
e7e72bf6 | 2190 | spin_lock_init(&conf->device_lock); |
dab8b292 TM |
2191 | INIT_LIST_HEAD(&conf->retry_list); |
2192 | ||
2193 | spin_lock_init(&conf->resync_lock); | |
2194 | init_waitqueue_head(&conf->wait_barrier); | |
2195 | ||
2196 | conf->thread = md_register_thread(raid10d, mddev, NULL); | |
2197 | if (!conf->thread) | |
2198 | goto out; | |
2199 | ||
dab8b292 TM |
2200 | conf->mddev = mddev; |
2201 | return conf; | |
2202 | ||
2203 | out: | |
128595ed | 2204 | printk(KERN_ERR "md/raid10:%s: couldn't allocate memory.\n", |
dab8b292 TM |
2205 | mdname(mddev)); |
2206 | if (conf) { | |
2207 | if (conf->r10bio_pool) | |
2208 | mempool_destroy(conf->r10bio_pool); | |
2209 | kfree(conf->mirrors); | |
2210 | safe_put_page(conf->tmppage); | |
2211 | kfree(conf); | |
2212 | } | |
2213 | return ERR_PTR(err); | |
2214 | } | |
2215 | ||
2216 | static int run(mddev_t *mddev) | |
2217 | { | |
2218 | conf_t *conf; | |
2219 | int i, disk_idx, chunk_size; | |
2220 | mirror_info_t *disk; | |
2221 | mdk_rdev_t *rdev; | |
2222 | sector_t size; | |
2223 | ||
2224 | /* | |
2225 | * copy the already verified devices into our private RAID10 | |
2226 | * bookkeeping area. [whatever we allocate in run(), | |
2227 | * should be freed in stop()] | |
2228 | */ | |
2229 | ||
2230 | if (mddev->private == NULL) { | |
2231 | conf = setup_conf(mddev); | |
2232 | if (IS_ERR(conf)) | |
2233 | return PTR_ERR(conf); | |
2234 | mddev->private = conf; | |
2235 | } | |
2236 | conf = mddev->private; | |
2237 | if (!conf) | |
2238 | goto out; | |
2239 | ||
dab8b292 TM |
2240 | mddev->thread = conf->thread; |
2241 | conf->thread = NULL; | |
2242 | ||
8f6c2e4b MP |
2243 | chunk_size = mddev->chunk_sectors << 9; |
2244 | blk_queue_io_min(mddev->queue, chunk_size); | |
2245 | if (conf->raid_disks % conf->near_copies) | |
2246 | blk_queue_io_opt(mddev->queue, chunk_size * conf->raid_disks); | |
2247 | else | |
2248 | blk_queue_io_opt(mddev->queue, chunk_size * | |
2249 | (conf->raid_disks / conf->near_copies)); | |
2250 | ||
159ec1fc | 2251 | list_for_each_entry(rdev, &mddev->disks, same_set) { |
1da177e4 | 2252 | disk_idx = rdev->raid_disk; |
84707f38 | 2253 | if (disk_idx >= conf->raid_disks |
1da177e4 LT |
2254 | || disk_idx < 0) |
2255 | continue; | |
2256 | disk = conf->mirrors + disk_idx; | |
2257 | ||
2258 | disk->rdev = rdev; | |
8f6c2e4b MP |
2259 | disk_stack_limits(mddev->gendisk, rdev->bdev, |
2260 | rdev->data_offset << 9); | |
1da177e4 | 2261 | /* as we don't honour merge_bvec_fn, we must never risk |
627a2d3c N |
2262 | * violating it, so limit max_segments to 1 lying |
2263 | * within a single page. | |
1da177e4 | 2264 | */ |
627a2d3c N |
2265 | if (rdev->bdev->bd_disk->queue->merge_bvec_fn) { |
2266 | blk_queue_max_segments(mddev->queue, 1); | |
2267 | blk_queue_segment_boundary(mddev->queue, | |
2268 | PAGE_CACHE_SIZE - 1); | |
2269 | } | |
1da177e4 LT |
2270 | |
2271 | disk->head_position = 0; | |
1da177e4 | 2272 | } |
6d508242 N |
2273 | /* need to check that every block has at least one working mirror */ |
2274 | if (!enough(conf)) { | |
128595ed | 2275 | printk(KERN_ERR "md/raid10:%s: not enough operational mirrors.\n", |
6d508242 | 2276 | mdname(mddev)); |
1da177e4 LT |
2277 | goto out_free_conf; |
2278 | } | |
2279 | ||
2280 | mddev->degraded = 0; | |
2281 | for (i = 0; i < conf->raid_disks; i++) { | |
2282 | ||
2283 | disk = conf->mirrors + i; | |
2284 | ||
5fd6c1dc | 2285 | if (!disk->rdev || |
2e333e89 | 2286 | !test_bit(In_sync, &disk->rdev->flags)) { |
1da177e4 LT |
2287 | disk->head_position = 0; |
2288 | mddev->degraded++; | |
8c2e870a NB |
2289 | if (disk->rdev) |
2290 | conf->fullsync = 1; | |
1da177e4 LT |
2291 | } |
2292 | } | |
2293 | ||
8c6ac868 | 2294 | if (mddev->recovery_cp != MaxSector) |
128595ed | 2295 | printk(KERN_NOTICE "md/raid10:%s: not clean" |
8c6ac868 AN |
2296 | " -- starting background reconstruction\n", |
2297 | mdname(mddev)); | |
1da177e4 | 2298 | printk(KERN_INFO |
128595ed | 2299 | "md/raid10:%s: active with %d out of %d devices\n", |
84707f38 N |
2300 | mdname(mddev), conf->raid_disks - mddev->degraded, |
2301 | conf->raid_disks); | |
1da177e4 LT |
2302 | /* |
2303 | * Ok, everything is just fine now | |
2304 | */ | |
dab8b292 TM |
2305 | mddev->dev_sectors = conf->dev_sectors; |
2306 | size = raid10_size(mddev, 0, 0); | |
2307 | md_set_array_sectors(mddev, size); | |
2308 | mddev->resync_max_sectors = size; | |
1da177e4 | 2309 | |
0d129228 N |
2310 | mddev->queue->backing_dev_info.congested_fn = raid10_congested; |
2311 | mddev->queue->backing_dev_info.congested_data = mddev; | |
7a5febe9 | 2312 | |
1da177e4 LT |
2313 | /* Calculate max read-ahead size. |
2314 | * We need to readahead at least twice a whole stripe.... | |
2315 | * maybe... | |
2316 | */ | |
2317 | { | |
9d8f0363 AN |
2318 | int stripe = conf->raid_disks * |
2319 | ((mddev->chunk_sectors << 9) / PAGE_SIZE); | |
1da177e4 LT |
2320 | stripe /= conf->near_copies; |
2321 | if (mddev->queue->backing_dev_info.ra_pages < 2* stripe) | |
2322 | mddev->queue->backing_dev_info.ra_pages = 2* stripe; | |
2323 | } | |
2324 | ||
84707f38 | 2325 | if (conf->near_copies < conf->raid_disks) |
1da177e4 | 2326 | blk_queue_merge_bvec(mddev->queue, raid10_mergeable_bvec); |
a91a2785 MP |
2327 | |
2328 | if (md_integrity_register(mddev)) | |
2329 | goto out_free_conf; | |
2330 | ||
1da177e4 LT |
2331 | return 0; |
2332 | ||
2333 | out_free_conf: | |
589a594b | 2334 | md_unregister_thread(mddev->thread); |
1da177e4 LT |
2335 | if (conf->r10bio_pool) |
2336 | mempool_destroy(conf->r10bio_pool); | |
1345b1d8 | 2337 | safe_put_page(conf->tmppage); |
990a8baf | 2338 | kfree(conf->mirrors); |
1da177e4 LT |
2339 | kfree(conf); |
2340 | mddev->private = NULL; | |
2341 | out: | |
2342 | return -EIO; | |
2343 | } | |
2344 | ||
2345 | static int stop(mddev_t *mddev) | |
2346 | { | |
070ec55d | 2347 | conf_t *conf = mddev->private; |
1da177e4 | 2348 | |
409c57f3 N |
2349 | raise_barrier(conf, 0); |
2350 | lower_barrier(conf); | |
2351 | ||
1da177e4 LT |
2352 | md_unregister_thread(mddev->thread); |
2353 | mddev->thread = NULL; | |
2354 | blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ | |
2355 | if (conf->r10bio_pool) | |
2356 | mempool_destroy(conf->r10bio_pool); | |
990a8baf | 2357 | kfree(conf->mirrors); |
1da177e4 LT |
2358 | kfree(conf); |
2359 | mddev->private = NULL; | |
2360 | return 0; | |
2361 | } | |
2362 | ||
6cce3b23 N |
2363 | static void raid10_quiesce(mddev_t *mddev, int state) |
2364 | { | |
070ec55d | 2365 | conf_t *conf = mddev->private; |
6cce3b23 N |
2366 | |
2367 | switch(state) { | |
2368 | case 1: | |
2369 | raise_barrier(conf, 0); | |
2370 | break; | |
2371 | case 0: | |
2372 | lower_barrier(conf); | |
2373 | break; | |
2374 | } | |
6cce3b23 | 2375 | } |
1da177e4 | 2376 | |
dab8b292 TM |
2377 | static void *raid10_takeover_raid0(mddev_t *mddev) |
2378 | { | |
2379 | mdk_rdev_t *rdev; | |
2380 | conf_t *conf; | |
2381 | ||
2382 | if (mddev->degraded > 0) { | |
128595ed N |
2383 | printk(KERN_ERR "md/raid10:%s: Error: degraded raid0!\n", |
2384 | mdname(mddev)); | |
dab8b292 TM |
2385 | return ERR_PTR(-EINVAL); |
2386 | } | |
2387 | ||
dab8b292 TM |
2388 | /* Set new parameters */ |
2389 | mddev->new_level = 10; | |
2390 | /* new layout: far_copies = 1, near_copies = 2 */ | |
2391 | mddev->new_layout = (1<<8) + 2; | |
2392 | mddev->new_chunk_sectors = mddev->chunk_sectors; | |
2393 | mddev->delta_disks = mddev->raid_disks; | |
dab8b292 TM |
2394 | mddev->raid_disks *= 2; |
2395 | /* make sure it will be not marked as dirty */ | |
2396 | mddev->recovery_cp = MaxSector; | |
2397 | ||
2398 | conf = setup_conf(mddev); | |
02214dc5 | 2399 | if (!IS_ERR(conf)) { |
e93f68a1 N |
2400 | list_for_each_entry(rdev, &mddev->disks, same_set) |
2401 | if (rdev->raid_disk >= 0) | |
2402 | rdev->new_raid_disk = rdev->raid_disk * 2; | |
02214dc5 KW |
2403 | conf->barrier = 1; |
2404 | } | |
2405 | ||
dab8b292 TM |
2406 | return conf; |
2407 | } | |
2408 | ||
2409 | static void *raid10_takeover(mddev_t *mddev) | |
2410 | { | |
2411 | struct raid0_private_data *raid0_priv; | |
2412 | ||
2413 | /* raid10 can take over: | |
2414 | * raid0 - providing it has only two drives | |
2415 | */ | |
2416 | if (mddev->level == 0) { | |
2417 | /* for raid0 takeover only one zone is supported */ | |
2418 | raid0_priv = mddev->private; | |
2419 | if (raid0_priv->nr_strip_zones > 1) { | |
128595ed N |
2420 | printk(KERN_ERR "md/raid10:%s: cannot takeover raid 0" |
2421 | " with more than one zone.\n", | |
2422 | mdname(mddev)); | |
dab8b292 TM |
2423 | return ERR_PTR(-EINVAL); |
2424 | } | |
2425 | return raid10_takeover_raid0(mddev); | |
2426 | } | |
2427 | return ERR_PTR(-EINVAL); | |
2428 | } | |
2429 | ||
2604b703 | 2430 | static struct mdk_personality raid10_personality = |
1da177e4 LT |
2431 | { |
2432 | .name = "raid10", | |
2604b703 | 2433 | .level = 10, |
1da177e4 LT |
2434 | .owner = THIS_MODULE, |
2435 | .make_request = make_request, | |
2436 | .run = run, | |
2437 | .stop = stop, | |
2438 | .status = status, | |
2439 | .error_handler = error, | |
2440 | .hot_add_disk = raid10_add_disk, | |
2441 | .hot_remove_disk= raid10_remove_disk, | |
2442 | .spare_active = raid10_spare_active, | |
2443 | .sync_request = sync_request, | |
6cce3b23 | 2444 | .quiesce = raid10_quiesce, |
80c3a6ce | 2445 | .size = raid10_size, |
dab8b292 | 2446 | .takeover = raid10_takeover, |
1da177e4 LT |
2447 | }; |
2448 | ||
2449 | static int __init raid_init(void) | |
2450 | { | |
2604b703 | 2451 | return register_md_personality(&raid10_personality); |
1da177e4 LT |
2452 | } |
2453 | ||
2454 | static void raid_exit(void) | |
2455 | { | |
2604b703 | 2456 | unregister_md_personality(&raid10_personality); |
1da177e4 LT |
2457 | } |
2458 | ||
2459 | module_init(raid_init); | |
2460 | module_exit(raid_exit); | |
2461 | MODULE_LICENSE("GPL"); | |
0efb9e61 | 2462 | MODULE_DESCRIPTION("RAID10 (striped mirror) personality for MD"); |
1da177e4 | 2463 | MODULE_ALIAS("md-personality-9"); /* RAID10 */ |
d9d166c2 | 2464 | MODULE_ALIAS("md-raid10"); |
2604b703 | 2465 | MODULE_ALIAS("md-level-10"); |