1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | raid0.c : Multiple Devices driver for Linux |
4 | Copyright (C) 1994-96 Marc ZYNGIER |
5 | <zyngier@ufr-info-p7.ibp.fr> or |
6 | <maz@gloups.fdn.fr> |
7 | Copyright (C) 1999, 2000 Ingo Molnar, Red Hat |
8 | |
9 | RAID-0 management functions. |
10 | |
11 | */ |
12 | |
13 | #include <linux/blkdev.h> |
14 | #include <linux/seq_file.h> |
15 | #include <linux/module.h> |
16 | #include <linux/slab.h> |
17 | #include <trace/events/block.h> |
18 | #include "md.h" |
19 | #include "raid0.h" |
20 | #include "raid5.h" |
21 | |
22 | static int default_layout = 0; |
23 | module_param(default_layout, int, 0644); |
24 | |
25 | #define UNSUPPORTED_MDDEV_FLAGS \ |
26 | ((1L << MD_HAS_JOURNAL) | \ |
27 | (1L << MD_JOURNAL_CLEAN) | \ |
28 | (1L << MD_FAILFAST_SUPPORTED) |\ |
29 | (1L << MD_HAS_PPL) | \ |
30 | (1L << MD_HAS_MULTIPLE_PPLS)) |
31 | |
32 | /* |
33 | * inform the user of the raid configuration |
34 | */ |
35 | static void dump_zones(struct mddev *mddev) |
36 | { |
37 | int j, k; |
38 | sector_t zone_size = 0; |
39 | sector_t zone_start = 0; |
40 | struct r0conf *conf = mddev->private; |
41 | int raid_disks = conf->strip_zone[0].nb_dev; |
42 | pr_debug("md: RAID0 configuration for %s - %d zone%s\n" , |
43 | mdname(mddev), |
44 | conf->nr_strip_zones, conf->nr_strip_zones==1?"" :"s" ); |
45 | for (j = 0; j < conf->nr_strip_zones; j++) { |
46 | char line[200]; |
47 | int len = 0; |
48 | |
49 | for (k = 0; k < conf->strip_zone[j].nb_dev; k++) |
50 | len += scnprintf(buf: line+len, size: 200-len, fmt: "%s%pg" , k?"/" :"" , |
51 | conf->devlist[j * raid_disks + k]->bdev); |
52 | pr_debug("md: zone%d=[%s]\n" , j, line); |
53 | |
54 | zone_size = conf->strip_zone[j].zone_end - zone_start; |
55 | pr_debug(" zone-offset=%10lluKB, device-offset=%10lluKB, size=%10lluKB\n" , |
56 | (unsigned long long)zone_start>>1, |
57 | (unsigned long long)conf->strip_zone[j].dev_start>>1, |
58 | (unsigned long long)zone_size>>1); |
59 | zone_start = conf->strip_zone[j].zone_end; |
60 | } |
61 | } |
62 | |
63 | static int create_strip_zones(struct mddev *mddev, struct r0conf **private_conf) |
64 | { |
65 | int i, c, err; |
66 | sector_t curr_zone_end, sectors; |
67 | struct md_rdev *smallest, *rdev1, *rdev2, *rdev, **dev; |
68 | struct strip_zone *zone; |
69 | int cnt; |
70 | struct r0conf *conf = kzalloc(size: sizeof(*conf), GFP_KERNEL); |
71 | unsigned blksize = 512; |
72 | |
73 | *private_conf = ERR_PTR(error: -ENOMEM); |
74 | if (!conf) |
75 | return -ENOMEM; |
76 | rdev_for_each(rdev1, mddev) { |
77 | pr_debug("md/raid0:%s: looking at %pg\n" , |
78 | mdname(mddev), |
79 | rdev1->bdev); |
80 | c = 0; |
81 | |
82 | /* round size to chunk_size */ |
83 | sectors = rdev1->sectors; |
84 | sector_div(sectors, mddev->chunk_sectors); |
85 | rdev1->sectors = sectors * mddev->chunk_sectors; |
86 | |
87 | blksize = max(blksize, queue_logical_block_size( |
88 | rdev1->bdev->bd_disk->queue)); |
89 | |
90 | rdev_for_each(rdev2, mddev) { |
91 | pr_debug("md/raid0:%s: comparing %pg(%llu)" |
92 | " with %pg(%llu)\n" , |
93 | mdname(mddev), |
94 | rdev1->bdev, |
95 | (unsigned long long)rdev1->sectors, |
96 | rdev2->bdev, |
97 | (unsigned long long)rdev2->sectors); |
98 | if (rdev2 == rdev1) { |
99 | pr_debug("md/raid0:%s: END\n" , |
100 | mdname(mddev)); |
101 | break; |
102 | } |
103 | if (rdev2->sectors == rdev1->sectors) { |
104 | /* |
105 | * Not unique, don't count it as a new |
106 | * group |
107 | */ |
108 | pr_debug("md/raid0:%s: EQUAL\n" , |
109 | mdname(mddev)); |
110 | c = 1; |
111 | break; |
112 | } |
113 | pr_debug("md/raid0:%s: NOT EQUAL\n" , |
114 | mdname(mddev)); |
115 | } |
116 | if (!c) { |
117 | pr_debug("md/raid0:%s: ==> UNIQUE\n" , |
118 | mdname(mddev)); |
119 | conf->nr_strip_zones++; |
120 | pr_debug("md/raid0:%s: %d zones\n" , |
121 | mdname(mddev), conf->nr_strip_zones); |
122 | } |
123 | } |
124 | pr_debug("md/raid0:%s: FINAL %d zones\n" , |
125 | mdname(mddev), conf->nr_strip_zones); |
126 | |
127 | /* |
128 | * now since we have the hard sector sizes, we can make sure |
129 | * chunk size is a multiple of that sector size |
130 | */ |
131 | if ((mddev->chunk_sectors << 9) % blksize) { |
132 | pr_warn("md/raid0:%s: chunk_size of %d not multiple of block size %d\n" , |
133 | mdname(mddev), |
134 | mddev->chunk_sectors << 9, blksize); |
135 | err = -EINVAL; |
136 | goto abort; |
137 | } |
138 | |
139 | err = -ENOMEM; |
140 | conf->strip_zone = kcalloc(n: conf->nr_strip_zones, |
141 | size: sizeof(struct strip_zone), |
142 | GFP_KERNEL); |
143 | if (!conf->strip_zone) |
144 | goto abort; |
145 | conf->devlist = kzalloc(array3_size(sizeof(struct md_rdev *), |
146 | conf->nr_strip_zones, |
147 | mddev->raid_disks), |
148 | GFP_KERNEL); |
149 | if (!conf->devlist) |
150 | goto abort; |
151 | |
152 | /* The first zone must contain all devices, so here we check that |
153 | * there is a proper alignment of slots to devices and find them all |
154 | */ |
155 | zone = &conf->strip_zone[0]; |
156 | cnt = 0; |
157 | smallest = NULL; |
158 | dev = conf->devlist; |
159 | err = -EINVAL; |
160 | rdev_for_each(rdev1, mddev) { |
161 | int j = rdev1->raid_disk; |
162 | |
163 | if (mddev->level == 10) { |
164 | /* taking over a raid10-n2 array */ |
165 | j /= 2; |
166 | rdev1->new_raid_disk = j; |
167 | } |
168 | |
169 | if (mddev->level == 1) { |
170 | /* taiking over a raid1 array- |
171 | * we have only one active disk |
172 | */ |
173 | j = 0; |
174 | rdev1->new_raid_disk = j; |
175 | } |
176 | |
177 | if (j < 0) { |
178 | pr_warn("md/raid0:%s: remove inactive devices before converting to RAID0\n" , |
179 | mdname(mddev)); |
180 | goto abort; |
181 | } |
182 | if (j >= mddev->raid_disks) { |
183 | pr_warn("md/raid0:%s: bad disk number %d - aborting!\n" , |
184 | mdname(mddev), j); |
185 | goto abort; |
186 | } |
187 | if (dev[j]) { |
188 | pr_warn("md/raid0:%s: multiple devices for %d - aborting!\n" , |
189 | mdname(mddev), j); |
190 | goto abort; |
191 | } |
192 | dev[j] = rdev1; |
193 | |
194 | if (!smallest || (rdev1->sectors < smallest->sectors)) |
195 | smallest = rdev1; |
196 | cnt++; |
197 | } |
198 | if (cnt != mddev->raid_disks) { |
199 | pr_warn("md/raid0:%s: too few disks (%d of %d) - aborting!\n" , |
200 | mdname(mddev), cnt, mddev->raid_disks); |
201 | goto abort; |
202 | } |
203 | zone->nb_dev = cnt; |
204 | zone->zone_end = smallest->sectors * cnt; |
205 | |
206 | curr_zone_end = zone->zone_end; |
207 | |
208 | /* now do the other zones */ |
209 | for (i = 1; i < conf->nr_strip_zones; i++) |
210 | { |
211 | int j; |
212 | |
213 | zone = conf->strip_zone + i; |
214 | dev = conf->devlist + i * mddev->raid_disks; |
215 | |
216 | pr_debug("md/raid0:%s: zone %d\n" , mdname(mddev), i); |
217 | zone->dev_start = smallest->sectors; |
218 | smallest = NULL; |
219 | c = 0; |
220 | |
221 | for (j=0; j<cnt; j++) { |
222 | rdev = conf->devlist[j]; |
223 | if (rdev->sectors <= zone->dev_start) { |
224 | pr_debug("md/raid0:%s: checking %pg ... nope\n" , |
225 | mdname(mddev), |
226 | rdev->bdev); |
227 | continue; |
228 | } |
229 | pr_debug("md/raid0:%s: checking %pg ..." |
230 | " contained as device %d\n" , |
231 | mdname(mddev), |
232 | rdev->bdev, c); |
233 | dev[c] = rdev; |
234 | c++; |
235 | if (!smallest || rdev->sectors < smallest->sectors) { |
236 | smallest = rdev; |
237 | pr_debug("md/raid0:%s: (%llu) is smallest!.\n" , |
238 | mdname(mddev), |
239 | (unsigned long long)rdev->sectors); |
240 | } |
241 | } |
242 | |
243 | zone->nb_dev = c; |
244 | sectors = (smallest->sectors - zone->dev_start) * c; |
245 | pr_debug("md/raid0:%s: zone->nb_dev: %d, sectors: %llu\n" , |
246 | mdname(mddev), |
247 | zone->nb_dev, (unsigned long long)sectors); |
248 | |
249 | curr_zone_end += sectors; |
250 | zone->zone_end = curr_zone_end; |
251 | |
252 | pr_debug("md/raid0:%s: current zone start: %llu\n" , |
253 | mdname(mddev), |
254 | (unsigned long long)smallest->sectors); |
255 | } |
256 | |
257 | if (conf->nr_strip_zones == 1 || conf->strip_zone[1].nb_dev == 1) { |
258 | conf->layout = RAID0_ORIG_LAYOUT; |
259 | } else if (mddev->layout == RAID0_ORIG_LAYOUT || |
260 | mddev->layout == RAID0_ALT_MULTIZONE_LAYOUT) { |
261 | conf->layout = mddev->layout; |
262 | } else if (default_layout == RAID0_ORIG_LAYOUT || |
263 | default_layout == RAID0_ALT_MULTIZONE_LAYOUT) { |
264 | conf->layout = default_layout; |
265 | } else { |
266 | pr_err("md/raid0:%s: cannot assemble multi-zone RAID0 with default_layout setting\n" , |
267 | mdname(mddev)); |
268 | pr_err("md/raid0: please set raid0.default_layout to 1 or 2\n" ); |
269 | err = -EOPNOTSUPP; |
270 | goto abort; |
271 | } |
272 | |
273 | if (conf->layout == RAID0_ORIG_LAYOUT) { |
274 | for (i = 1; i < conf->nr_strip_zones; i++) { |
275 | sector_t first_sector = conf->strip_zone[i-1].zone_end; |
276 | |
277 | sector_div(first_sector, mddev->chunk_sectors); |
278 | zone = conf->strip_zone + i; |
279 | /* disk_shift is first disk index used in the zone */ |
280 | zone->disk_shift = sector_div(first_sector, |
281 | zone->nb_dev); |
282 | } |
283 | } |
284 | |
285 | pr_debug("md/raid0:%s: done.\n" , mdname(mddev)); |
286 | *private_conf = conf; |
287 | |
288 | return 0; |
289 | abort: |
290 | kfree(objp: conf->strip_zone); |
291 | kfree(objp: conf->devlist); |
292 | kfree(objp: conf); |
293 | *private_conf = ERR_PTR(error: err); |
294 | return err; |
295 | } |
296 | |
297 | /* Find the zone which holds a particular offset |
298 | * Update *sectorp to be an offset in that zone |
299 | */ |
300 | static struct strip_zone *find_zone(struct r0conf *conf, |
301 | sector_t *sectorp) |
302 | { |
303 | int i; |
304 | struct strip_zone *z = conf->strip_zone; |
305 | sector_t sector = *sectorp; |
306 | |
307 | for (i = 0; i < conf->nr_strip_zones; i++) |
308 | if (sector < z[i].zone_end) { |
309 | if (i) |
310 | *sectorp = sector - z[i-1].zone_end; |
311 | return z + i; |
312 | } |
313 | BUG(); |
314 | } |
315 | |
316 | /* |
317 | * remaps the bio to the target device. we separate two flows. |
318 | * power 2 flow and a general flow for the sake of performance |
319 | */ |
320 | static struct md_rdev *map_sector(struct mddev *mddev, struct strip_zone *zone, |
321 | sector_t sector, sector_t *sector_offset) |
322 | { |
323 | unsigned int sect_in_chunk; |
324 | sector_t chunk; |
325 | struct r0conf *conf = mddev->private; |
326 | int raid_disks = conf->strip_zone[0].nb_dev; |
327 | unsigned int chunk_sects = mddev->chunk_sectors; |
328 | |
329 | if (is_power_of_2(n: chunk_sects)) { |
330 | int chunksect_bits = ffz(~chunk_sects); |
331 | /* find the sector offset inside the chunk */ |
332 | sect_in_chunk = sector & (chunk_sects - 1); |
333 | sector >>= chunksect_bits; |
334 | /* chunk in zone */ |
335 | chunk = *sector_offset; |
336 | /* quotient is the chunk in real device*/ |
337 | sector_div(chunk, zone->nb_dev << chunksect_bits); |
338 | } else{ |
339 | sect_in_chunk = sector_div(sector, chunk_sects); |
340 | chunk = *sector_offset; |
341 | sector_div(chunk, chunk_sects * zone->nb_dev); |
342 | } |
343 | /* |
344 | * position the bio over the real device |
345 | * real sector = chunk in device + starting of zone |
346 | * + the position in the chunk |
347 | */ |
348 | *sector_offset = (chunk * chunk_sects) + sect_in_chunk; |
349 | return conf->devlist[(zone - conf->strip_zone)*raid_disks |
350 | + sector_div(sector, zone->nb_dev)]; |
351 | } |
352 | |
353 | static sector_t raid0_size(struct mddev *mddev, sector_t sectors, int raid_disks) |
354 | { |
355 | sector_t array_sectors = 0; |
356 | struct md_rdev *rdev; |
357 | |
358 | WARN_ONCE(sectors || raid_disks, |
359 | "%s does not support generic reshape\n" , __func__); |
360 | |
361 | rdev_for_each(rdev, mddev) |
362 | array_sectors += (rdev->sectors & |
363 | ~(sector_t)(mddev->chunk_sectors-1)); |
364 | |
365 | return array_sectors; |
366 | } |
367 | |
368 | static void free_conf(struct mddev *mddev, struct r0conf *conf) |
369 | { |
370 | kfree(objp: conf->strip_zone); |
371 | kfree(objp: conf->devlist); |
372 | kfree(objp: conf); |
373 | } |
374 | |
375 | static void raid0_free(struct mddev *mddev, void *priv) |
376 | { |
377 | struct r0conf *conf = priv; |
378 | |
379 | free_conf(mddev, conf); |
380 | } |
381 | |
382 | static int raid0_run(struct mddev *mddev) |
383 | { |
384 | struct r0conf *conf; |
385 | int ret; |
386 | |
387 | if (mddev->chunk_sectors == 0) { |
388 | pr_warn("md/raid0:%s: chunk size must be set.\n" , mdname(mddev)); |
389 | return -EINVAL; |
390 | } |
391 | if (md_check_no_bitmap(mddev)) |
392 | return -EINVAL; |
393 | |
394 | /* if private is not null, we are here after takeover */ |
395 | if (mddev->private == NULL) { |
396 | ret = create_strip_zones(mddev, private_conf: &conf); |
397 | if (ret < 0) |
398 | return ret; |
399 | mddev->private = conf; |
400 | } |
401 | conf = mddev->private; |
402 | if (mddev->queue) { |
403 | struct md_rdev *rdev; |
404 | |
405 | blk_queue_max_hw_sectors(mddev->queue, mddev->chunk_sectors); |
406 | blk_queue_max_write_zeroes_sectors(q: mddev->queue, max_write_same_sectors: mddev->chunk_sectors); |
407 | |
408 | blk_queue_io_min(q: mddev->queue, min: mddev->chunk_sectors << 9); |
409 | blk_queue_io_opt(q: mddev->queue, |
410 | opt: (mddev->chunk_sectors << 9) * mddev->raid_disks); |
411 | |
412 | rdev_for_each(rdev, mddev) { |
413 | disk_stack_limits(disk: mddev->gendisk, bdev: rdev->bdev, |
414 | offset: rdev->data_offset << 9); |
415 | } |
416 | } |
417 | |
418 | /* calculate array device size */ |
419 | md_set_array_sectors(mddev, array_sectors: raid0_size(mddev, sectors: 0, raid_disks: 0)); |
420 | |
421 | pr_debug("md/raid0:%s: md_size is %llu sectors.\n" , |
422 | mdname(mddev), |
423 | (unsigned long long)mddev->array_sectors); |
424 | |
425 | dump_zones(mddev); |
426 | |
427 | ret = md_integrity_register(mddev); |
428 | if (ret) |
429 | free_conf(mddev, conf); |
430 | |
431 | return ret; |
432 | } |
433 | |
434 | /* |
435 | * Convert disk_index to the disk order in which it is read/written. |
436 | * For example, if we have 4 disks, they are numbered 0,1,2,3. If we |
437 | * write the disks starting at disk 3, then the read/write order would |
438 | * be disk 3, then 0, then 1, and then disk 2 and we want map_disk_shift() |
439 | * to map the disks as follows 0,1,2,3 => 1,2,3,0. So disk 0 would map |
440 | * to 1, 1 to 2, 2 to 3, and 3 to 0. That way we can compare disks in |
441 | * that 'output' space to understand the read/write disk ordering. |
442 | */ |
443 | static int map_disk_shift(int disk_index, int num_disks, int disk_shift) |
444 | { |
445 | return ((disk_index + num_disks - disk_shift) % num_disks); |
446 | } |
447 | |
448 | static void raid0_handle_discard(struct mddev *mddev, struct bio *bio) |
449 | { |
450 | struct r0conf *conf = mddev->private; |
451 | struct strip_zone *zone; |
452 | sector_t start = bio->bi_iter.bi_sector; |
453 | sector_t end; |
454 | unsigned int stripe_size; |
455 | sector_t first_stripe_index, last_stripe_index; |
456 | sector_t start_disk_offset; |
457 | unsigned int start_disk_index; |
458 | sector_t end_disk_offset; |
459 | unsigned int end_disk_index; |
460 | unsigned int disk; |
461 | sector_t orig_start, orig_end; |
462 | |
463 | orig_start = start; |
464 | zone = find_zone(conf, sectorp: &start); |
465 | |
466 | if (bio_end_sector(bio) > zone->zone_end) { |
467 | struct bio *split = bio_split(bio, |
468 | sectors: zone->zone_end - bio->bi_iter.bi_sector, GFP_NOIO, |
469 | bs: &mddev->bio_set); |
470 | bio_chain(split, bio); |
471 | submit_bio_noacct(bio); |
472 | bio = split; |
473 | end = zone->zone_end; |
474 | } else |
475 | end = bio_end_sector(bio); |
476 | |
477 | orig_end = end; |
478 | if (zone != conf->strip_zone) |
479 | end = end - zone[-1].zone_end; |
480 | |
481 | /* Now start and end is the offset in zone */ |
482 | stripe_size = zone->nb_dev * mddev->chunk_sectors; |
483 | |
484 | first_stripe_index = start; |
485 | sector_div(first_stripe_index, stripe_size); |
486 | last_stripe_index = end; |
487 | sector_div(last_stripe_index, stripe_size); |
488 | |
489 | /* In the first zone the original and alternate layouts are the same */ |
490 | if ((conf->layout == RAID0_ORIG_LAYOUT) && (zone != conf->strip_zone)) { |
491 | sector_div(orig_start, mddev->chunk_sectors); |
492 | start_disk_index = sector_div(orig_start, zone->nb_dev); |
493 | start_disk_index = map_disk_shift(disk_index: start_disk_index, |
494 | num_disks: zone->nb_dev, |
495 | disk_shift: zone->disk_shift); |
496 | sector_div(orig_end, mddev->chunk_sectors); |
497 | end_disk_index = sector_div(orig_end, zone->nb_dev); |
498 | end_disk_index = map_disk_shift(disk_index: end_disk_index, |
499 | num_disks: zone->nb_dev, disk_shift: zone->disk_shift); |
500 | } else { |
501 | start_disk_index = (int)(start - first_stripe_index * stripe_size) / |
502 | mddev->chunk_sectors; |
503 | end_disk_index = (int)(end - last_stripe_index * stripe_size) / |
504 | mddev->chunk_sectors; |
505 | } |
506 | start_disk_offset = ((int)(start - first_stripe_index * stripe_size) % |
507 | mddev->chunk_sectors) + |
508 | first_stripe_index * mddev->chunk_sectors; |
509 | end_disk_offset = ((int)(end - last_stripe_index * stripe_size) % |
510 | mddev->chunk_sectors) + |
511 | last_stripe_index * mddev->chunk_sectors; |
512 | |
513 | for (disk = 0; disk < zone->nb_dev; disk++) { |
514 | sector_t dev_start, dev_end; |
515 | struct md_rdev *rdev; |
516 | int compare_disk; |
517 | |
518 | compare_disk = map_disk_shift(disk_index: disk, num_disks: zone->nb_dev, |
519 | disk_shift: zone->disk_shift); |
520 | |
521 | if (compare_disk < start_disk_index) |
522 | dev_start = (first_stripe_index + 1) * |
523 | mddev->chunk_sectors; |
524 | else if (compare_disk > start_disk_index) |
525 | dev_start = first_stripe_index * mddev->chunk_sectors; |
526 | else |
527 | dev_start = start_disk_offset; |
528 | |
529 | if (compare_disk < end_disk_index) |
530 | dev_end = (last_stripe_index + 1) * mddev->chunk_sectors; |
531 | else if (compare_disk > end_disk_index) |
532 | dev_end = last_stripe_index * mddev->chunk_sectors; |
533 | else |
534 | dev_end = end_disk_offset; |
535 | |
536 | if (dev_end <= dev_start) |
537 | continue; |
538 | |
539 | rdev = conf->devlist[(zone - conf->strip_zone) * |
540 | conf->strip_zone[0].nb_dev + disk]; |
541 | md_submit_discard_bio(mddev, rdev, bio, |
542 | start: dev_start + zone->dev_start + rdev->data_offset, |
543 | size: dev_end - dev_start); |
544 | } |
545 | bio_endio(bio); |
546 | } |
547 | |
548 | static void raid0_map_submit_bio(struct mddev *mddev, struct bio *bio) |
549 | { |
550 | struct r0conf *conf = mddev->private; |
551 | struct strip_zone *zone; |
552 | struct md_rdev *tmp_dev; |
553 | sector_t bio_sector = bio->bi_iter.bi_sector; |
554 | sector_t sector = bio_sector; |
555 | |
556 | md_account_bio(mddev, bio: &bio); |
557 | |
558 | zone = find_zone(conf: mddev->private, sectorp: §or); |
559 | switch (conf->layout) { |
560 | case RAID0_ORIG_LAYOUT: |
561 | tmp_dev = map_sector(mddev, zone, sector: bio_sector, sector_offset: §or); |
562 | break; |
563 | case RAID0_ALT_MULTIZONE_LAYOUT: |
564 | tmp_dev = map_sector(mddev, zone, sector, sector_offset: §or); |
565 | break; |
566 | default: |
567 | WARN(1, "md/raid0:%s: Invalid layout\n" , mdname(mddev)); |
568 | bio_io_error(bio); |
569 | return; |
570 | } |
571 | |
572 | if (unlikely(is_rdev_broken(tmp_dev))) { |
573 | bio_io_error(bio); |
574 | md_error(mddev, rdev: tmp_dev); |
575 | return; |
576 | } |
577 | |
578 | bio_set_dev(bio, bdev: tmp_dev->bdev); |
579 | bio->bi_iter.bi_sector = sector + zone->dev_start + |
580 | tmp_dev->data_offset; |
581 | |
582 | if (mddev->gendisk) |
583 | trace_block_bio_remap(bio, dev: disk_devt(disk: mddev->gendisk), |
584 | from: bio_sector); |
585 | mddev_check_write_zeroes(mddev, bio); |
586 | submit_bio_noacct(bio); |
587 | } |
588 | |
589 | static bool raid0_make_request(struct mddev *mddev, struct bio *bio) |
590 | { |
591 | sector_t sector; |
592 | unsigned chunk_sects; |
593 | unsigned sectors; |
594 | |
595 | if (unlikely(bio->bi_opf & REQ_PREFLUSH) |
596 | && md_flush_request(mddev, bio)) |
597 | return true; |
598 | |
599 | if (unlikely((bio_op(bio) == REQ_OP_DISCARD))) { |
600 | raid0_handle_discard(mddev, bio); |
601 | return true; |
602 | } |
603 | |
604 | sector = bio->bi_iter.bi_sector; |
605 | chunk_sects = mddev->chunk_sectors; |
606 | |
607 | sectors = chunk_sects - |
608 | (likely(is_power_of_2(chunk_sects)) |
609 | ? (sector & (chunk_sects-1)) |
610 | : sector_div(sector, chunk_sects)); |
611 | |
612 | if (sectors < bio_sectors(bio)) { |
613 | struct bio *split = bio_split(bio, sectors, GFP_NOIO, |
614 | bs: &mddev->bio_set); |
615 | bio_chain(split, bio); |
616 | raid0_map_submit_bio(mddev, bio); |
617 | bio = split; |
618 | } |
619 | |
620 | raid0_map_submit_bio(mddev, bio); |
621 | return true; |
622 | } |
623 | |
624 | static void raid0_status(struct seq_file *seq, struct mddev *mddev) |
625 | { |
626 | seq_printf(m: seq, fmt: " %dk chunks" , mddev->chunk_sectors / 2); |
627 | return; |
628 | } |
629 | |
630 | static void raid0_error(struct mddev *mddev, struct md_rdev *rdev) |
631 | { |
632 | if (!test_and_set_bit(nr: MD_BROKEN, addr: &mddev->flags)) { |
633 | char *md_name = mdname(mddev); |
634 | |
635 | pr_crit("md/raid0%s: Disk failure on %pg detected, failing array.\n" , |
636 | md_name, rdev->bdev); |
637 | } |
638 | } |
639 | |
640 | static void *raid0_takeover_raid45(struct mddev *mddev) |
641 | { |
642 | struct md_rdev *rdev; |
643 | struct r0conf *priv_conf; |
644 | |
645 | if (mddev->degraded != 1) { |
646 | pr_warn("md/raid0:%s: raid5 must be degraded! Degraded disks: %d\n" , |
647 | mdname(mddev), |
648 | mddev->degraded); |
649 | return ERR_PTR(error: -EINVAL); |
650 | } |
651 | |
652 | rdev_for_each(rdev, mddev) { |
653 | /* check slot number for a disk */ |
654 | if (rdev->raid_disk == mddev->raid_disks-1) { |
655 | pr_warn("md/raid0:%s: raid5 must have missing parity disk!\n" , |
656 | mdname(mddev)); |
657 | return ERR_PTR(error: -EINVAL); |
658 | } |
659 | rdev->sectors = mddev->dev_sectors; |
660 | } |
661 | |
662 | /* Set new parameters */ |
663 | mddev->new_level = 0; |
664 | mddev->new_layout = 0; |
665 | mddev->new_chunk_sectors = mddev->chunk_sectors; |
666 | mddev->raid_disks--; |
667 | mddev->delta_disks = -1; |
668 | /* make sure it will be not marked as dirty */ |
669 | mddev->recovery_cp = MaxSector; |
670 | mddev_clear_unsupported_flags(mddev, UNSUPPORTED_MDDEV_FLAGS); |
671 | |
672 | create_strip_zones(mddev, private_conf: &priv_conf); |
673 | |
674 | return priv_conf; |
675 | } |
676 | |
677 | static void *raid0_takeover_raid10(struct mddev *mddev) |
678 | { |
679 | struct r0conf *priv_conf; |
680 | |
681 | /* Check layout: |
682 | * - far_copies must be 1 |
683 | * - near_copies must be 2 |
684 | * - disks number must be even |
685 | * - all mirrors must be already degraded |
686 | */ |
687 | if (mddev->layout != ((1 << 8) + 2)) { |
688 | pr_warn("md/raid0:%s:: Raid0 cannot takeover layout: 0x%x\n" , |
689 | mdname(mddev), |
690 | mddev->layout); |
691 | return ERR_PTR(error: -EINVAL); |
692 | } |
693 | if (mddev->raid_disks & 1) { |
694 | pr_warn("md/raid0:%s: Raid0 cannot takeover Raid10 with odd disk number.\n" , |
695 | mdname(mddev)); |
696 | return ERR_PTR(error: -EINVAL); |
697 | } |
698 | if (mddev->degraded != (mddev->raid_disks>>1)) { |
699 | pr_warn("md/raid0:%s: All mirrors must be already degraded!\n" , |
700 | mdname(mddev)); |
701 | return ERR_PTR(error: -EINVAL); |
702 | } |
703 | |
704 | /* Set new parameters */ |
705 | mddev->new_level = 0; |
706 | mddev->new_layout = 0; |
707 | mddev->new_chunk_sectors = mddev->chunk_sectors; |
708 | mddev->delta_disks = - mddev->raid_disks / 2; |
709 | mddev->raid_disks += mddev->delta_disks; |
710 | mddev->degraded = 0; |
711 | /* make sure it will be not marked as dirty */ |
712 | mddev->recovery_cp = MaxSector; |
713 | mddev_clear_unsupported_flags(mddev, UNSUPPORTED_MDDEV_FLAGS); |
714 | |
715 | create_strip_zones(mddev, private_conf: &priv_conf); |
716 | return priv_conf; |
717 | } |
718 | |
719 | static void *raid0_takeover_raid1(struct mddev *mddev) |
720 | { |
721 | struct r0conf *priv_conf; |
722 | int chunksect; |
723 | |
724 | /* Check layout: |
725 | * - (N - 1) mirror drives must be already faulty |
726 | */ |
727 | if ((mddev->raid_disks - 1) != mddev->degraded) { |
728 | pr_err("md/raid0:%s: (N - 1) mirrors drives must be already faulty!\n" , |
729 | mdname(mddev)); |
730 | return ERR_PTR(error: -EINVAL); |
731 | } |
732 | |
733 | /* |
734 | * a raid1 doesn't have the notion of chunk size, so |
735 | * figure out the largest suitable size we can use. |
736 | */ |
737 | chunksect = 64 * 2; /* 64K by default */ |
738 | |
739 | /* The array must be an exact multiple of chunksize */ |
740 | while (chunksect && (mddev->array_sectors & (chunksect - 1))) |
741 | chunksect >>= 1; |
742 | |
743 | if ((chunksect << 9) < PAGE_SIZE) |
744 | /* array size does not allow a suitable chunk size */ |
745 | return ERR_PTR(error: -EINVAL); |
746 | |
747 | /* Set new parameters */ |
748 | mddev->new_level = 0; |
749 | mddev->new_layout = 0; |
750 | mddev->new_chunk_sectors = chunksect; |
751 | mddev->chunk_sectors = chunksect; |
752 | mddev->delta_disks = 1 - mddev->raid_disks; |
753 | mddev->raid_disks = 1; |
754 | /* make sure it will be not marked as dirty */ |
755 | mddev->recovery_cp = MaxSector; |
756 | mddev_clear_unsupported_flags(mddev, UNSUPPORTED_MDDEV_FLAGS); |
757 | |
758 | create_strip_zones(mddev, private_conf: &priv_conf); |
759 | return priv_conf; |
760 | } |
761 | |
762 | static void *raid0_takeover(struct mddev *mddev) |
763 | { |
764 | /* raid0 can take over: |
765 | * raid4 - if all data disks are active. |
766 | * raid5 - providing it is Raid4 layout and one disk is faulty |
767 | * raid10 - assuming we have all necessary active disks |
768 | * raid1 - with (N -1) mirror drives faulty |
769 | */ |
770 | |
771 | if (mddev->bitmap) { |
772 | pr_warn("md/raid0: %s: cannot takeover array with bitmap\n" , |
773 | mdname(mddev)); |
774 | return ERR_PTR(error: -EBUSY); |
775 | } |
776 | if (mddev->level == 4) |
777 | return raid0_takeover_raid45(mddev); |
778 | |
779 | if (mddev->level == 5) { |
780 | if (mddev->layout == ALGORITHM_PARITY_N) |
781 | return raid0_takeover_raid45(mddev); |
782 | |
783 | pr_warn("md/raid0:%s: Raid can only takeover Raid5 with layout: %d\n" , |
784 | mdname(mddev), ALGORITHM_PARITY_N); |
785 | } |
786 | |
787 | if (mddev->level == 10) |
788 | return raid0_takeover_raid10(mddev); |
789 | |
790 | if (mddev->level == 1) |
791 | return raid0_takeover_raid1(mddev); |
792 | |
793 | pr_warn("Takeover from raid%i to raid0 not supported\n" , |
794 | mddev->level); |
795 | |
796 | return ERR_PTR(error: -EINVAL); |
797 | } |
798 | |
799 | static void raid0_quiesce(struct mddev *mddev, int quiesce) |
800 | { |
801 | } |
802 | |
803 | static struct md_personality raid0_personality= |
804 | { |
805 | .name = "raid0" , |
806 | .level = 0, |
807 | .owner = THIS_MODULE, |
808 | .make_request = raid0_make_request, |
809 | .run = raid0_run, |
810 | .free = raid0_free, |
811 | .status = raid0_status, |
812 | .size = raid0_size, |
813 | .takeover = raid0_takeover, |
814 | .quiesce = raid0_quiesce, |
815 | .error_handler = raid0_error, |
816 | }; |
817 | |
818 | static int __init raid0_init (void) |
819 | { |
820 | return register_md_personality (p: &raid0_personality); |
821 | } |
822 | |
823 | static void raid0_exit (void) |
824 | { |
825 | unregister_md_personality (p: &raid0_personality); |
826 | } |
827 | |
828 | module_init(raid0_init); |
829 | module_exit(raid0_exit); |
830 | MODULE_LICENSE("GPL" ); |
831 | MODULE_DESCRIPTION("RAID0 (striping) personality for MD" ); |
832 | MODULE_ALIAS("md-personality-2" ); /* RAID0 */ |
833 | MODULE_ALIAS("md-raid0" ); |
834 | MODULE_ALIAS("md-level-0" ); |
835 | |