1 /* 2 raid0.c : Multiple Devices driver for Linux 3 Copyright (C) 1994-96 Marc ZYNGIER 4 <zyngier@ufr-info-p7.ibp.fr> or 5 <maz@gloups.fdn.fr> 6 Copyright (C) 1999, 2000 Ingo Molnar, Red Hat 7 8 9 RAID-0 management functions. 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 21 #include <linux/blkdev.h> 22 #include <linux/seq_file.h> 23 #include <linux/module.h> 24 #include <linux/slab.h> 25 #include "md.h" 26 #include "raid0.h" 27 #include "raid5.h" 28 29 static int raid0_congested(void *data, int bits) 30 { 31 struct mddev *mddev = data; 32 struct r0conf *conf = mddev->private; 33 struct md_rdev **devlist = conf->devlist; 34 int raid_disks = conf->strip_zone[0].nb_dev; 35 int i, ret = 0; 36 37 if (mddev_congested(mddev, bits)) 38 return 1; 39 40 for (i = 0; i < raid_disks && !ret ; i++) { 41 struct request_queue *q = bdev_get_queue(devlist[i]->bdev); 42 43 ret |= bdi_congested(&q->backing_dev_info, bits); 44 } 45 return ret; 46 } 47 48 /* 49 * inform the user of the raid configuration 50 */ 51 static void dump_zones(struct mddev *mddev) 52 { 53 int j, k; 54 sector_t zone_size = 0; 55 sector_t zone_start = 0; 56 char b[BDEVNAME_SIZE]; 57 struct r0conf *conf = mddev->private; 58 int raid_disks = conf->strip_zone[0].nb_dev; 59 printk(KERN_INFO "md: RAID0 configuration for %s - %d zone%s\n", 60 mdname(mddev), 61 conf->nr_strip_zones, conf->nr_strip_zones==1?"":"s"); 62 for (j = 0; j < conf->nr_strip_zones; j++) { 63 printk(KERN_INFO "md: zone%d=[", j); 64 for (k = 0; k < conf->strip_zone[j].nb_dev; k++) 65 printk(KERN_CONT "%s%s", k?"/":"", 66 bdevname(conf->devlist[j*raid_disks 67 + k]->bdev, b)); 68 printk(KERN_CONT "]\n"); 69 70 zone_size = conf->strip_zone[j].zone_end - zone_start; 71 printk(KERN_INFO " zone-offset=%10lluKB, " 72 "device-offset=%10lluKB, size=%10lluKB\n", 73 (unsigned long long)zone_start>>1, 74 (unsigned long long)conf->strip_zone[j].dev_start>>1, 75 (unsigned long long)zone_size>>1); 76 zone_start = conf->strip_zone[j].zone_end; 77 } 78 printk(KERN_INFO "\n"); 79 } 80 81 static int create_strip_zones(struct mddev *mddev, struct r0conf **private_conf) 82 { 83 int i, c, err; 84 sector_t curr_zone_end, sectors; 85 struct md_rdev *smallest, *rdev1, *rdev2, *rdev, **dev; 86 struct strip_zone *zone; 87 int cnt; 88 char b[BDEVNAME_SIZE]; 89 char b2[BDEVNAME_SIZE]; 90 struct r0conf *conf = kzalloc(sizeof(*conf), GFP_KERNEL); 91 92 if (!conf) 93 return -ENOMEM; 94 list_for_each_entry(rdev1, &mddev->disks, same_set) { 95 pr_debug("md/raid0:%s: looking at %s\n", 96 mdname(mddev), 97 bdevname(rdev1->bdev, b)); 98 c = 0; 99 100 /* round size to chunk_size */ 101 sectors = rdev1->sectors; 102 sector_div(sectors, mddev->chunk_sectors); 103 rdev1->sectors = sectors * mddev->chunk_sectors; 104 105 list_for_each_entry(rdev2, &mddev->disks, same_set) { 106 pr_debug("md/raid0:%s: comparing %s(%llu)" 107 " with %s(%llu)\n", 108 mdname(mddev), 109 bdevname(rdev1->bdev,b), 110 (unsigned long long)rdev1->sectors, 111 bdevname(rdev2->bdev,b2), 112 (unsigned long long)rdev2->sectors); 113 if (rdev2 == rdev1) { 114 pr_debug("md/raid0:%s: END\n", 115 mdname(mddev)); 116 break; 117 } 118 if (rdev2->sectors == rdev1->sectors) { 119 /* 120 * Not unique, don't count it as a new 121 * group 122 */ 123 pr_debug("md/raid0:%s: EQUAL\n", 124 mdname(mddev)); 125 c = 1; 126 break; 127 } 128 pr_debug("md/raid0:%s: NOT EQUAL\n", 129 mdname(mddev)); 130 } 131 if (!c) { 132 pr_debug("md/raid0:%s: ==> UNIQUE\n", 133 mdname(mddev)); 134 conf->nr_strip_zones++; 135 pr_debug("md/raid0:%s: %d zones\n", 136 mdname(mddev), conf->nr_strip_zones); 137 } 138 } 139 pr_debug("md/raid0:%s: FINAL %d zones\n", 140 mdname(mddev), conf->nr_strip_zones); 141 err = -ENOMEM; 142 conf->strip_zone = kzalloc(sizeof(struct strip_zone)* 143 conf->nr_strip_zones, GFP_KERNEL); 144 if (!conf->strip_zone) 145 goto abort; 146 conf->devlist = kzalloc(sizeof(struct md_rdev*)* 147 conf->nr_strip_zones*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 list_for_each_entry(rdev1, &mddev->disks, same_set) { 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 || j >= mddev->raid_disks) { 178 printk(KERN_ERR "md/raid0:%s: bad disk number %d - " 179 "aborting!\n", mdname(mddev), j); 180 goto abort; 181 } 182 if (dev[j]) { 183 printk(KERN_ERR "md/raid0:%s: multiple devices for %d - " 184 "aborting!\n", mdname(mddev), j); 185 goto abort; 186 } 187 dev[j] = rdev1; 188 189 disk_stack_limits(mddev->gendisk, rdev1->bdev, 190 rdev1->data_offset << 9); 191 /* as we don't honour merge_bvec_fn, we must never risk 192 * violating it, so limit ->max_segments to 1, lying within 193 * a single page. 194 */ 195 196 if (rdev1->bdev->bd_disk->queue->merge_bvec_fn) { 197 blk_queue_max_segments(mddev->queue, 1); 198 blk_queue_segment_boundary(mddev->queue, 199 PAGE_CACHE_SIZE - 1); 200 } 201 if (!smallest || (rdev1->sectors < smallest->sectors)) 202 smallest = rdev1; 203 cnt++; 204 } 205 if (cnt != mddev->raid_disks) { 206 printk(KERN_ERR "md/raid0:%s: too few disks (%d of %d) - " 207 "aborting!\n", mdname(mddev), cnt, mddev->raid_disks); 208 goto abort; 209 } 210 zone->nb_dev = cnt; 211 zone->zone_end = smallest->sectors * cnt; 212 213 curr_zone_end = zone->zone_end; 214 215 /* now do the other zones */ 216 for (i = 1; i < conf->nr_strip_zones; i++) 217 { 218 int j; 219 220 zone = conf->strip_zone + i; 221 dev = conf->devlist + i * mddev->raid_disks; 222 223 pr_debug("md/raid0:%s: zone %d\n", mdname(mddev), i); 224 zone->dev_start = smallest->sectors; 225 smallest = NULL; 226 c = 0; 227 228 for (j=0; j<cnt; j++) { 229 rdev = conf->devlist[j]; 230 if (rdev->sectors <= zone->dev_start) { 231 pr_debug("md/raid0:%s: checking %s ... nope\n", 232 mdname(mddev), 233 bdevname(rdev->bdev, b)); 234 continue; 235 } 236 pr_debug("md/raid0:%s: checking %s ..." 237 " contained as device %d\n", 238 mdname(mddev), 239 bdevname(rdev->bdev, b), c); 240 dev[c] = rdev; 241 c++; 242 if (!smallest || rdev->sectors < smallest->sectors) { 243 smallest = rdev; 244 pr_debug("md/raid0:%s: (%llu) is smallest!.\n", 245 mdname(mddev), 246 (unsigned long long)rdev->sectors); 247 } 248 } 249 250 zone->nb_dev = c; 251 sectors = (smallest->sectors - zone->dev_start) * c; 252 pr_debug("md/raid0:%s: zone->nb_dev: %d, sectors: %llu\n", 253 mdname(mddev), 254 zone->nb_dev, (unsigned long long)sectors); 255 256 curr_zone_end += sectors; 257 zone->zone_end = curr_zone_end; 258 259 pr_debug("md/raid0:%s: current zone start: %llu\n", 260 mdname(mddev), 261 (unsigned long long)smallest->sectors); 262 } 263 mddev->queue->backing_dev_info.congested_fn = raid0_congested; 264 mddev->queue->backing_dev_info.congested_data = mddev; 265 266 /* 267 * now since we have the hard sector sizes, we can make sure 268 * chunk size is a multiple of that sector size 269 */ 270 if ((mddev->chunk_sectors << 9) % queue_logical_block_size(mddev->queue)) { 271 printk(KERN_ERR "md/raid0:%s: chunk_size of %d not valid\n", 272 mdname(mddev), 273 mddev->chunk_sectors << 9); 274 goto abort; 275 } 276 277 blk_queue_io_min(mddev->queue, mddev->chunk_sectors << 9); 278 blk_queue_io_opt(mddev->queue, 279 (mddev->chunk_sectors << 9) * mddev->raid_disks); 280 281 pr_debug("md/raid0:%s: done.\n", mdname(mddev)); 282 *private_conf = conf; 283 284 return 0; 285 abort: 286 kfree(conf->strip_zone); 287 kfree(conf->devlist); 288 kfree(conf); 289 *private_conf = NULL; 290 return err; 291 } 292 293 /** 294 * raid0_mergeable_bvec -- tell bio layer if a two requests can be merged 295 * @q: request queue 296 * @bvm: properties of new bio 297 * @biovec: the request that could be merged to it. 298 * 299 * Return amount of bytes we can accept at this offset 300 */ 301 static int raid0_mergeable_bvec(struct request_queue *q, 302 struct bvec_merge_data *bvm, 303 struct bio_vec *biovec) 304 { 305 struct mddev *mddev = q->queuedata; 306 sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev); 307 int max; 308 unsigned int chunk_sectors = mddev->chunk_sectors; 309 unsigned int bio_sectors = bvm->bi_size >> 9; 310 311 if (is_power_of_2(chunk_sectors)) 312 max = (chunk_sectors - ((sector & (chunk_sectors-1)) 313 + bio_sectors)) << 9; 314 else 315 max = (chunk_sectors - (sector_div(sector, chunk_sectors) 316 + bio_sectors)) << 9; 317 if (max < 0) max = 0; /* bio_add cannot handle a negative return */ 318 if (max <= biovec->bv_len && bio_sectors == 0) 319 return biovec->bv_len; 320 else 321 return max; 322 } 323 324 static sector_t raid0_size(struct mddev *mddev, sector_t sectors, int raid_disks) 325 { 326 sector_t array_sectors = 0; 327 struct md_rdev *rdev; 328 329 WARN_ONCE(sectors || raid_disks, 330 "%s does not support generic reshape\n", __func__); 331 332 list_for_each_entry(rdev, &mddev->disks, same_set) 333 array_sectors += rdev->sectors; 334 335 return array_sectors; 336 } 337 338 static int raid0_run(struct mddev *mddev) 339 { 340 struct r0conf *conf; 341 int ret; 342 343 if (mddev->chunk_sectors == 0) { 344 printk(KERN_ERR "md/raid0:%s: chunk size must be set.\n", 345 mdname(mddev)); 346 return -EINVAL; 347 } 348 if (md_check_no_bitmap(mddev)) 349 return -EINVAL; 350 blk_queue_max_hw_sectors(mddev->queue, mddev->chunk_sectors); 351 352 /* if private is not null, we are here after takeover */ 353 if (mddev->private == NULL) { 354 ret = create_strip_zones(mddev, &conf); 355 if (ret < 0) 356 return ret; 357 mddev->private = conf; 358 } 359 conf = mddev->private; 360 361 /* calculate array device size */ 362 md_set_array_sectors(mddev, raid0_size(mddev, 0, 0)); 363 364 printk(KERN_INFO "md/raid0:%s: md_size is %llu sectors.\n", 365 mdname(mddev), 366 (unsigned long long)mddev->array_sectors); 367 /* calculate the max read-ahead size. 368 * For read-ahead of large files to be effective, we need to 369 * readahead at least twice a whole stripe. i.e. number of devices 370 * multiplied by chunk size times 2. 371 * If an individual device has an ra_pages greater than the 372 * chunk size, then we will not drive that device as hard as it 373 * wants. We consider this a configuration error: a larger 374 * chunksize should be used in that case. 375 */ 376 { 377 int stripe = mddev->raid_disks * 378 (mddev->chunk_sectors << 9) / PAGE_SIZE; 379 if (mddev->queue->backing_dev_info.ra_pages < 2* stripe) 380 mddev->queue->backing_dev_info.ra_pages = 2* stripe; 381 } 382 383 blk_queue_merge_bvec(mddev->queue, raid0_mergeable_bvec); 384 dump_zones(mddev); 385 return md_integrity_register(mddev); 386 } 387 388 static int raid0_stop(struct mddev *mddev) 389 { 390 struct r0conf *conf = mddev->private; 391 392 blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ 393 kfree(conf->strip_zone); 394 kfree(conf->devlist); 395 kfree(conf); 396 mddev->private = NULL; 397 return 0; 398 } 399 400 /* Find the zone which holds a particular offset 401 * Update *sectorp to be an offset in that zone 402 */ 403 static struct strip_zone *find_zone(struct r0conf *conf, 404 sector_t *sectorp) 405 { 406 int i; 407 struct strip_zone *z = conf->strip_zone; 408 sector_t sector = *sectorp; 409 410 for (i = 0; i < conf->nr_strip_zones; i++) 411 if (sector < z[i].zone_end) { 412 if (i) 413 *sectorp = sector - z[i-1].zone_end; 414 return z + i; 415 } 416 BUG(); 417 } 418 419 /* 420 * remaps the bio to the target device. we separate two flows. 421 * power 2 flow and a general flow for the sake of perfromance 422 */ 423 static struct md_rdev *map_sector(struct mddev *mddev, struct strip_zone *zone, 424 sector_t sector, sector_t *sector_offset) 425 { 426 unsigned int sect_in_chunk; 427 sector_t chunk; 428 struct r0conf *conf = mddev->private; 429 int raid_disks = conf->strip_zone[0].nb_dev; 430 unsigned int chunk_sects = mddev->chunk_sectors; 431 432 if (is_power_of_2(chunk_sects)) { 433 int chunksect_bits = ffz(~chunk_sects); 434 /* find the sector offset inside the chunk */ 435 sect_in_chunk = sector & (chunk_sects - 1); 436 sector >>= chunksect_bits; 437 /* chunk in zone */ 438 chunk = *sector_offset; 439 /* quotient is the chunk in real device*/ 440 sector_div(chunk, zone->nb_dev << chunksect_bits); 441 } else{ 442 sect_in_chunk = sector_div(sector, chunk_sects); 443 chunk = *sector_offset; 444 sector_div(chunk, chunk_sects * zone->nb_dev); 445 } 446 /* 447 * position the bio over the real device 448 * real sector = chunk in device + starting of zone 449 * + the position in the chunk 450 */ 451 *sector_offset = (chunk * chunk_sects) + sect_in_chunk; 452 return conf->devlist[(zone - conf->strip_zone)*raid_disks 453 + sector_div(sector, zone->nb_dev)]; 454 } 455 456 /* 457 * Is io distribute over 1 or more chunks ? 458 */ 459 static inline int is_io_in_chunk_boundary(struct mddev *mddev, 460 unsigned int chunk_sects, struct bio *bio) 461 { 462 if (likely(is_power_of_2(chunk_sects))) { 463 return chunk_sects >= ((bio->bi_sector & (chunk_sects-1)) 464 + (bio->bi_size >> 9)); 465 } else{ 466 sector_t sector = bio->bi_sector; 467 return chunk_sects >= (sector_div(sector, chunk_sects) 468 + (bio->bi_size >> 9)); 469 } 470 } 471 472 static void raid0_make_request(struct mddev *mddev, struct bio *bio) 473 { 474 unsigned int chunk_sects; 475 sector_t sector_offset; 476 struct strip_zone *zone; 477 struct md_rdev *tmp_dev; 478 479 if (unlikely(bio->bi_rw & REQ_FLUSH)) { 480 md_flush_request(mddev, bio); 481 return; 482 } 483 484 chunk_sects = mddev->chunk_sectors; 485 if (unlikely(!is_io_in_chunk_boundary(mddev, chunk_sects, bio))) { 486 sector_t sector = bio->bi_sector; 487 struct bio_pair *bp; 488 /* Sanity check -- queue functions should prevent this happening */ 489 if (bio->bi_vcnt != 1 || 490 bio->bi_idx != 0) 491 goto bad_map; 492 /* This is a one page bio that upper layers 493 * refuse to split for us, so we need to split it. 494 */ 495 if (likely(is_power_of_2(chunk_sects))) 496 bp = bio_split(bio, chunk_sects - (sector & 497 (chunk_sects-1))); 498 else 499 bp = bio_split(bio, chunk_sects - 500 sector_div(sector, chunk_sects)); 501 raid0_make_request(mddev, &bp->bio1); 502 raid0_make_request(mddev, &bp->bio2); 503 bio_pair_release(bp); 504 return; 505 } 506 507 sector_offset = bio->bi_sector; 508 zone = find_zone(mddev->private, §or_offset); 509 tmp_dev = map_sector(mddev, zone, bio->bi_sector, 510 §or_offset); 511 bio->bi_bdev = tmp_dev->bdev; 512 bio->bi_sector = sector_offset + zone->dev_start + 513 tmp_dev->data_offset; 514 515 generic_make_request(bio); 516 return; 517 518 bad_map: 519 printk("md/raid0:%s: make_request bug: can't convert block across chunks" 520 " or bigger than %dk %llu %d\n", 521 mdname(mddev), chunk_sects / 2, 522 (unsigned long long)bio->bi_sector, bio->bi_size >> 10); 523 524 bio_io_error(bio); 525 return; 526 } 527 528 static void raid0_status(struct seq_file *seq, struct mddev *mddev) 529 { 530 seq_printf(seq, " %dk chunks", mddev->chunk_sectors / 2); 531 return; 532 } 533 534 static void *raid0_takeover_raid45(struct mddev *mddev) 535 { 536 struct md_rdev *rdev; 537 struct r0conf *priv_conf; 538 539 if (mddev->degraded != 1) { 540 printk(KERN_ERR "md/raid0:%s: raid5 must be degraded! Degraded disks: %d\n", 541 mdname(mddev), 542 mddev->degraded); 543 return ERR_PTR(-EINVAL); 544 } 545 546 list_for_each_entry(rdev, &mddev->disks, same_set) { 547 /* check slot number for a disk */ 548 if (rdev->raid_disk == mddev->raid_disks-1) { 549 printk(KERN_ERR "md/raid0:%s: raid5 must have missing parity disk!\n", 550 mdname(mddev)); 551 return ERR_PTR(-EINVAL); 552 } 553 } 554 555 /* Set new parameters */ 556 mddev->new_level = 0; 557 mddev->new_layout = 0; 558 mddev->new_chunk_sectors = mddev->chunk_sectors; 559 mddev->raid_disks--; 560 mddev->delta_disks = -1; 561 /* make sure it will be not marked as dirty */ 562 mddev->recovery_cp = MaxSector; 563 564 create_strip_zones(mddev, &priv_conf); 565 return priv_conf; 566 } 567 568 static void *raid0_takeover_raid10(struct mddev *mddev) 569 { 570 struct r0conf *priv_conf; 571 572 /* Check layout: 573 * - far_copies must be 1 574 * - near_copies must be 2 575 * - disks number must be even 576 * - all mirrors must be already degraded 577 */ 578 if (mddev->layout != ((1 << 8) + 2)) { 579 printk(KERN_ERR "md/raid0:%s:: Raid0 cannot takover layout: 0x%x\n", 580 mdname(mddev), 581 mddev->layout); 582 return ERR_PTR(-EINVAL); 583 } 584 if (mddev->raid_disks & 1) { 585 printk(KERN_ERR "md/raid0:%s: Raid0 cannot takover Raid10 with odd disk number.\n", 586 mdname(mddev)); 587 return ERR_PTR(-EINVAL); 588 } 589 if (mddev->degraded != (mddev->raid_disks>>1)) { 590 printk(KERN_ERR "md/raid0:%s: All mirrors must be already degraded!\n", 591 mdname(mddev)); 592 return ERR_PTR(-EINVAL); 593 } 594 595 /* Set new parameters */ 596 mddev->new_level = 0; 597 mddev->new_layout = 0; 598 mddev->new_chunk_sectors = mddev->chunk_sectors; 599 mddev->delta_disks = - mddev->raid_disks / 2; 600 mddev->raid_disks += mddev->delta_disks; 601 mddev->degraded = 0; 602 /* make sure it will be not marked as dirty */ 603 mddev->recovery_cp = MaxSector; 604 605 create_strip_zones(mddev, &priv_conf); 606 return priv_conf; 607 } 608 609 static void *raid0_takeover_raid1(struct mddev *mddev) 610 { 611 struct r0conf *priv_conf; 612 613 /* Check layout: 614 * - (N - 1) mirror drives must be already faulty 615 */ 616 if ((mddev->raid_disks - 1) != mddev->degraded) { 617 printk(KERN_ERR "md/raid0:%s: (N - 1) mirrors drives must be already faulty!\n", 618 mdname(mddev)); 619 return ERR_PTR(-EINVAL); 620 } 621 622 /* Set new parameters */ 623 mddev->new_level = 0; 624 mddev->new_layout = 0; 625 mddev->new_chunk_sectors = 128; /* by default set chunk size to 64k */ 626 mddev->delta_disks = 1 - mddev->raid_disks; 627 mddev->raid_disks = 1; 628 /* make sure it will be not marked as dirty */ 629 mddev->recovery_cp = MaxSector; 630 631 create_strip_zones(mddev, &priv_conf); 632 return priv_conf; 633 } 634 635 static void *raid0_takeover(struct mddev *mddev) 636 { 637 /* raid0 can take over: 638 * raid4 - if all data disks are active. 639 * raid5 - providing it is Raid4 layout and one disk is faulty 640 * raid10 - assuming we have all necessary active disks 641 * raid1 - with (N -1) mirror drives faulty 642 */ 643 if (mddev->level == 4) 644 return raid0_takeover_raid45(mddev); 645 646 if (mddev->level == 5) { 647 if (mddev->layout == ALGORITHM_PARITY_N) 648 return raid0_takeover_raid45(mddev); 649 650 printk(KERN_ERR "md/raid0:%s: Raid can only takeover Raid5 with layout: %d\n", 651 mdname(mddev), ALGORITHM_PARITY_N); 652 } 653 654 if (mddev->level == 10) 655 return raid0_takeover_raid10(mddev); 656 657 if (mddev->level == 1) 658 return raid0_takeover_raid1(mddev); 659 660 printk(KERN_ERR "Takeover from raid%i to raid0 not supported\n", 661 mddev->level); 662 663 return ERR_PTR(-EINVAL); 664 } 665 666 static void raid0_quiesce(struct mddev *mddev, int state) 667 { 668 } 669 670 static struct md_personality raid0_personality= 671 { 672 .name = "raid0", 673 .level = 0, 674 .owner = THIS_MODULE, 675 .make_request = raid0_make_request, 676 .run = raid0_run, 677 .stop = raid0_stop, 678 .status = raid0_status, 679 .size = raid0_size, 680 .takeover = raid0_takeover, 681 .quiesce = raid0_quiesce, 682 }; 683 684 static int __init raid0_init (void) 685 { 686 return register_md_personality (&raid0_personality); 687 } 688 689 static void raid0_exit (void) 690 { 691 unregister_md_personality (&raid0_personality); 692 } 693 694 module_init(raid0_init); 695 module_exit(raid0_exit); 696 MODULE_LICENSE("GPL"); 697 MODULE_DESCRIPTION("RAID0 (striping) personality for MD"); 698 MODULE_ALIAS("md-personality-2"); /* RAID0 */ 699 MODULE_ALIAS("md-raid0"); 700 MODULE_ALIAS("md-level-0"); 701