Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | linear.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 | |
| 7 | Linear mode management functions. |
| 8 | |
| 9 | This program is free software; you can redistribute it and/or modify |
| 10 | it under the terms of the GNU General Public License as published by |
| 11 | the Free Software Foundation; either version 2, or (at your option) |
| 12 | any later version. |
| 13 | |
| 14 | You should have received a copy of the GNU General Public License |
| 15 | (for example /usr/src/linux/COPYING); if not, write to the Free |
| 16 | Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 17 | */ |
| 18 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | #include <linux/raid/linear.h> |
| 20 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 21 | /* |
| 22 | * find which device holds a particular offset |
| 23 | */ |
| 24 | static inline dev_info_t *which_dev(mddev_t *mddev, sector_t sector) |
| 25 | { |
| 26 | dev_info_t *hash; |
| 27 | linear_conf_t *conf = mddev_to_conf(mddev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 28 | |
| 29 | /* |
| 30 | * sector_div(a,b) returns the remainer and sets a to a/b |
| 31 | */ |
Andre Noll | ab5bd5c | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 32 | sector >>= conf->sector_shift; |
| 33 | (void)sector_div(sector, conf->spacing); |
| 34 | hash = conf->hash_table[sector]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | |
Andre Noll | 6283815 | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 36 | while (sector >= hash->num_sectors + hash->start_sector) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 37 | hash++; |
| 38 | return hash; |
| 39 | } |
| 40 | |
| 41 | /** |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 42 | * linear_mergeable_bvec -- tell bio layer if two requests can be merged |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | * @q: request queue |
Alasdair G Kergon | cc371e6 | 2008-07-03 09:53:43 +0200 | [diff] [blame] | 44 | * @bvm: properties of new bio |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 45 | * @biovec: the request that could be merged to it. |
| 46 | * |
| 47 | * Return amount of bytes we can take at this offset |
| 48 | */ |
Alasdair G Kergon | cc371e6 | 2008-07-03 09:53:43 +0200 | [diff] [blame] | 49 | static int linear_mergeable_bvec(struct request_queue *q, |
| 50 | struct bvec_merge_data *bvm, |
| 51 | struct bio_vec *biovec) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 52 | { |
| 53 | mddev_t *mddev = q->queuedata; |
| 54 | dev_info_t *dev0; |
Alasdair G Kergon | cc371e6 | 2008-07-03 09:53:43 +0200 | [diff] [blame] | 55 | unsigned long maxsectors, bio_sectors = bvm->bi_size >> 9; |
| 56 | sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | |
| 58 | dev0 = which_dev(mddev, sector); |
Andre Noll | 6283815 | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 59 | maxsectors = dev0->num_sectors - (sector - dev0->start_sector); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 60 | |
| 61 | if (maxsectors < bio_sectors) |
| 62 | maxsectors = 0; |
| 63 | else |
| 64 | maxsectors -= bio_sectors; |
| 65 | |
| 66 | if (maxsectors <= (PAGE_SIZE >> 9 ) && bio_sectors == 0) |
| 67 | return biovec->bv_len; |
| 68 | /* The bytes available at this offset could be really big, |
| 69 | * so we cap at 2^31 to avoid overflow */ |
| 70 | if (maxsectors > (1 << (31-9))) |
| 71 | return 1<<31; |
| 72 | return maxsectors << 9; |
| 73 | } |
| 74 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 75 | static void linear_unplug(struct request_queue *q) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 76 | { |
| 77 | mddev_t *mddev = q->queuedata; |
| 78 | linear_conf_t *conf = mddev_to_conf(mddev); |
| 79 | int i; |
| 80 | |
| 81 | for (i=0; i < mddev->raid_disks; i++) { |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 82 | struct request_queue *r_queue = bdev_get_queue(conf->disks[i].rdev->bdev); |
Alan D. Brunelle | 2ad8b1e | 2007-11-07 14:26:56 -0500 | [diff] [blame] | 83 | blk_unplug(r_queue); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 84 | } |
| 85 | } |
| 86 | |
NeilBrown | 26be34d | 2006-10-03 01:15:53 -0700 | [diff] [blame] | 87 | static int linear_congested(void *data, int bits) |
| 88 | { |
| 89 | mddev_t *mddev = data; |
| 90 | linear_conf_t *conf = mddev_to_conf(mddev); |
| 91 | int i, ret = 0; |
| 92 | |
| 93 | for (i = 0; i < mddev->raid_disks && !ret ; i++) { |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 94 | struct request_queue *q = bdev_get_queue(conf->disks[i].rdev->bdev); |
NeilBrown | 26be34d | 2006-10-03 01:15:53 -0700 | [diff] [blame] | 95 | ret |= bdi_congested(&q->backing_dev_info, bits); |
| 96 | } |
| 97 | return ret; |
| 98 | } |
| 99 | |
NeilBrown | 7c7546c | 2006-06-26 00:27:41 -0700 | [diff] [blame] | 100 | static linear_conf_t *linear_conf(mddev_t *mddev, int raid_disks) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 101 | { |
| 102 | linear_conf_t *conf; |
| 103 | dev_info_t **table; |
| 104 | mdk_rdev_t *rdev; |
| 105 | int i, nb_zone, cnt; |
Andre Noll | 23242fb | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 106 | sector_t min_sectors; |
Andre Noll | 6283815 | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 107 | sector_t curr_sector; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 108 | |
NeilBrown | 7c7546c | 2006-06-26 00:27:41 -0700 | [diff] [blame] | 109 | conf = kzalloc (sizeof (*conf) + raid_disks*sizeof(dev_info_t), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 110 | GFP_KERNEL); |
| 111 | if (!conf) |
NeilBrown | 7c7546c | 2006-06-26 00:27:41 -0700 | [diff] [blame] | 112 | return NULL; |
| 113 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 114 | cnt = 0; |
Andre Noll | d6e2215 | 2008-07-21 17:05:25 +1000 | [diff] [blame] | 115 | conf->array_sectors = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | |
Cheng Renquan | 159ec1f | 2009-01-09 08:31:08 +1100 | [diff] [blame] | 117 | list_for_each_entry(rdev, &mddev->disks, same_set) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 118 | int j = rdev->raid_disk; |
| 119 | dev_info_t *disk = conf->disks + j; |
| 120 | |
Nikanth Karthikesan | 1386451 | 2008-06-28 08:31:19 +1000 | [diff] [blame] | 121 | if (j < 0 || j >= raid_disks || disk->rdev) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 122 | printk("linear: disk numbering problem. Aborting!\n"); |
| 123 | goto out; |
| 124 | } |
| 125 | |
| 126 | disk->rdev = rdev; |
| 127 | |
| 128 | blk_queue_stack_limits(mddev->queue, |
| 129 | rdev->bdev->bd_disk->queue); |
| 130 | /* as we don't honour merge_bvec_fn, we must never risk |
| 131 | * violating it, so limit ->max_sector to one PAGE, as |
| 132 | * a one page request is never in violation. |
| 133 | */ |
| 134 | if (rdev->bdev->bd_disk->queue->merge_bvec_fn && |
| 135 | mddev->queue->max_sectors > (PAGE_SIZE>>9)) |
| 136 | blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9); |
| 137 | |
Andre Noll | 6283815 | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 138 | disk->num_sectors = rdev->size * 2; |
Andre Noll | d6e2215 | 2008-07-21 17:05:25 +1000 | [diff] [blame] | 139 | conf->array_sectors += rdev->size * 2; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 140 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 141 | cnt++; |
| 142 | } |
NeilBrown | 7c7546c | 2006-06-26 00:27:41 -0700 | [diff] [blame] | 143 | if (cnt != raid_disks) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 144 | printk("linear: not enough drives present. Aborting!\n"); |
| 145 | goto out; |
| 146 | } |
| 147 | |
Andre Noll | 23242fb | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 148 | min_sectors = conf->array_sectors; |
| 149 | sector_div(min_sectors, PAGE_SIZE/sizeof(struct dev_info *)); |
Andre Noll | f1cd14a | 2008-11-06 19:41:24 +1100 | [diff] [blame] | 150 | if (min_sectors == 0) |
| 151 | min_sectors = 1; |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 152 | |
Andre Noll | 23242fb | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 153 | /* min_sectors is the minimum spacing that will fit the hash |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 154 | * table in one PAGE. This may be much smaller than needed. |
| 155 | * We find the smallest non-terminal set of consecutive devices |
Andre Noll | 23242fb | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 156 | * that is larger than min_sectors and use the size of that as |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 157 | * the actual spacing |
| 158 | */ |
Andre Noll | ab5bd5c | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 159 | conf->spacing = conf->array_sectors; |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 160 | for (i=0; i < cnt-1 ; i++) { |
Andre Noll | 23242fb | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 161 | sector_t tmp = 0; |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 162 | int j; |
Andre Noll | 23242fb | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 163 | for (j = i; j < cnt - 1 && tmp < min_sectors; j++) |
| 164 | tmp += conf->disks[j].num_sectors; |
Andre Noll | ab5bd5c | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 165 | if (tmp >= min_sectors && tmp < conf->spacing) |
| 166 | conf->spacing = tmp; |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 167 | } |
| 168 | |
Andre Noll | ab5bd5c | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 169 | /* spacing may be too large for sector_div to work with, |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 170 | * so we might need to pre-shift |
| 171 | */ |
Andre Noll | ab5bd5c | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 172 | conf->sector_shift = 0; |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 173 | if (sizeof(sector_t) > sizeof(u32)) { |
Andre Noll | ab5bd5c | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 174 | sector_t space = conf->spacing; |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 175 | while (space > (sector_t)(~(u32)0)) { |
| 176 | space >>= 1; |
Andre Noll | ab5bd5c | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 177 | conf->sector_shift++; |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 178 | } |
| 179 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 180 | /* |
| 181 | * This code was restructured to work around a gcc-2.95.3 internal |
| 182 | * compiler error. Alter it with care. |
| 183 | */ |
| 184 | { |
| 185 | sector_t sz; |
| 186 | unsigned round; |
| 187 | unsigned long base; |
| 188 | |
Andre Noll | ab5bd5c | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 189 | sz = conf->array_sectors >> conf->sector_shift; |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 190 | sz += 1; /* force round-up */ |
Andre Noll | ab5bd5c | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 191 | base = conf->spacing >> conf->sector_shift; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 192 | round = sector_div(sz, base); |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 193 | nb_zone = sz + (round ? 1 : 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 194 | } |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 195 | BUG_ON(nb_zone > PAGE_SIZE / sizeof(struct dev_info *)); |
| 196 | |
| 197 | conf->hash_table = kmalloc (sizeof (struct dev_info *) * nb_zone, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 198 | GFP_KERNEL); |
| 199 | if (!conf->hash_table) |
| 200 | goto out; |
| 201 | |
| 202 | /* |
| 203 | * Here we generate the linear hash table |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 204 | * First calculate the device offsets. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 205 | */ |
Andre Noll | 6283815 | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 206 | conf->disks[0].start_sector = 0; |
NeilBrown | a778b73 | 2007-05-23 13:58:10 -0700 | [diff] [blame] | 207 | for (i = 1; i < raid_disks; i++) |
Andre Noll | 6283815 | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 208 | conf->disks[i].start_sector = |
| 209 | conf->disks[i-1].start_sector + |
| 210 | conf->disks[i-1].num_sectors; |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 211 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 212 | table = conf->hash_table; |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 213 | i = 0; |
Andre Noll | 6283815 | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 214 | for (curr_sector = 0; |
| 215 | curr_sector < conf->array_sectors; |
Andre Noll | ab5bd5c | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 216 | curr_sector += conf->spacing) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 217 | |
NeilBrown | a778b73 | 2007-05-23 13:58:10 -0700 | [diff] [blame] | 218 | while (i < raid_disks-1 && |
Andre Noll | 6283815 | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 219 | curr_sector >= conf->disks[i+1].start_sector) |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 220 | i++; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 221 | |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 222 | *table ++ = conf->disks + i; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 223 | } |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 224 | |
Andre Noll | ab5bd5c | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 225 | if (conf->sector_shift) { |
| 226 | conf->spacing >>= conf->sector_shift; |
| 227 | /* round spacing up so that when we divide by it, |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 228 | * we err on the side of "too-low", which is safest. |
| 229 | */ |
Andre Noll | ab5bd5c | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 230 | conf->spacing++; |
NeilBrown | 15945fe | 2005-09-09 16:23:47 -0700 | [diff] [blame] | 231 | } |
| 232 | |
| 233 | BUG_ON(table - conf->hash_table > nb_zone); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 234 | |
NeilBrown | 7c7546c | 2006-06-26 00:27:41 -0700 | [diff] [blame] | 235 | return conf; |
| 236 | |
| 237 | out: |
| 238 | kfree(conf); |
| 239 | return NULL; |
| 240 | } |
| 241 | |
| 242 | static int linear_run (mddev_t *mddev) |
| 243 | { |
| 244 | linear_conf_t *conf; |
| 245 | |
Neil Brown | e7e72bf | 2008-05-14 16:05:54 -0700 | [diff] [blame] | 246 | mddev->queue->queue_lock = &mddev->queue->__queue_lock; |
NeilBrown | 7c7546c | 2006-06-26 00:27:41 -0700 | [diff] [blame] | 247 | conf = linear_conf(mddev, mddev->raid_disks); |
| 248 | |
| 249 | if (!conf) |
| 250 | return 1; |
| 251 | mddev->private = conf; |
Andre Noll | d6e2215 | 2008-07-21 17:05:25 +1000 | [diff] [blame] | 252 | mddev->array_sectors = conf->array_sectors; |
NeilBrown | 7c7546c | 2006-06-26 00:27:41 -0700 | [diff] [blame] | 253 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 254 | blk_queue_merge_bvec(mddev->queue, linear_mergeable_bvec); |
| 255 | mddev->queue->unplug_fn = linear_unplug; |
NeilBrown | 26be34d | 2006-10-03 01:15:53 -0700 | [diff] [blame] | 256 | mddev->queue->backing_dev_info.congested_fn = linear_congested; |
| 257 | mddev->queue->backing_dev_info.congested_data = mddev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 258 | return 0; |
NeilBrown | 7c7546c | 2006-06-26 00:27:41 -0700 | [diff] [blame] | 259 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 260 | |
NeilBrown | 7c7546c | 2006-06-26 00:27:41 -0700 | [diff] [blame] | 261 | static int linear_add(mddev_t *mddev, mdk_rdev_t *rdev) |
| 262 | { |
| 263 | /* Adding a drive to a linear array allows the array to grow. |
| 264 | * It is permitted if the new drive has a matching superblock |
| 265 | * already on it, with raid_disk equal to raid_disks. |
| 266 | * It is achieved by creating a new linear_private_data structure |
| 267 | * and swapping it in in-place of the current one. |
| 268 | * The current one is never freed until the array is stopped. |
| 269 | * This avoids races. |
| 270 | */ |
| 271 | linear_conf_t *newconf; |
| 272 | |
NeilBrown | a778b73 | 2007-05-23 13:58:10 -0700 | [diff] [blame] | 273 | if (rdev->saved_raid_disk != mddev->raid_disks) |
NeilBrown | 7c7546c | 2006-06-26 00:27:41 -0700 | [diff] [blame] | 274 | return -EINVAL; |
| 275 | |
NeilBrown | a778b73 | 2007-05-23 13:58:10 -0700 | [diff] [blame] | 276 | rdev->raid_disk = rdev->saved_raid_disk; |
| 277 | |
NeilBrown | 7c7546c | 2006-06-26 00:27:41 -0700 | [diff] [blame] | 278 | newconf = linear_conf(mddev,mddev->raid_disks+1); |
| 279 | |
| 280 | if (!newconf) |
| 281 | return -ENOMEM; |
| 282 | |
| 283 | newconf->prev = mddev_to_conf(mddev); |
| 284 | mddev->private = newconf; |
| 285 | mddev->raid_disks++; |
Andre Noll | d6e2215 | 2008-07-21 17:05:25 +1000 | [diff] [blame] | 286 | mddev->array_sectors = newconf->array_sectors; |
Andre Noll | f233ea5 | 2008-07-21 17:05:22 +1000 | [diff] [blame] | 287 | set_capacity(mddev->gendisk, mddev->array_sectors); |
NeilBrown | 7c7546c | 2006-06-26 00:27:41 -0700 | [diff] [blame] | 288 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 289 | } |
| 290 | |
| 291 | static int linear_stop (mddev_t *mddev) |
| 292 | { |
| 293 | linear_conf_t *conf = mddev_to_conf(mddev); |
| 294 | |
| 295 | blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ |
NeilBrown | 7c7546c | 2006-06-26 00:27:41 -0700 | [diff] [blame] | 296 | do { |
| 297 | linear_conf_t *t = conf->prev; |
| 298 | kfree(conf->hash_table); |
| 299 | kfree(conf); |
| 300 | conf = t; |
| 301 | } while (conf); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 302 | |
| 303 | return 0; |
| 304 | } |
| 305 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 306 | static int linear_make_request (struct request_queue *q, struct bio *bio) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 307 | { |
Jens Axboe | a362357 | 2005-11-01 09:26:16 +0100 | [diff] [blame] | 308 | const int rw = bio_data_dir(bio); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 309 | mddev_t *mddev = q->queuedata; |
| 310 | dev_info_t *tmp_dev; |
Tejun Heo | c995905 | 2008-08-25 19:47:21 +0900 | [diff] [blame] | 311 | int cpu; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 312 | |
NeilBrown | e5dcdd8 | 2005-09-09 16:23:41 -0700 | [diff] [blame] | 313 | if (unlikely(bio_barrier(bio))) { |
NeilBrown | 6712ecf | 2007-09-27 12:47:43 +0200 | [diff] [blame] | 314 | bio_endio(bio, -EOPNOTSUPP); |
NeilBrown | e5dcdd8 | 2005-09-09 16:23:41 -0700 | [diff] [blame] | 315 | return 0; |
| 316 | } |
| 317 | |
Tejun Heo | 074a7ac | 2008-08-25 19:56:14 +0900 | [diff] [blame] | 318 | cpu = part_stat_lock(); |
| 319 | part_stat_inc(cpu, &mddev->gendisk->part0, ios[rw]); |
| 320 | part_stat_add(cpu, &mddev->gendisk->part0, sectors[rw], |
| 321 | bio_sectors(bio)); |
| 322 | part_stat_unlock(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 323 | |
| 324 | tmp_dev = which_dev(mddev, bio->bi_sector); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 325 | |
Andre Noll | 6283815 | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 326 | if (unlikely(bio->bi_sector >= (tmp_dev->num_sectors + |
| 327 | tmp_dev->start_sector) |
| 328 | || (bio->bi_sector < |
| 329 | tmp_dev->start_sector))) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 330 | char b[BDEVNAME_SIZE]; |
| 331 | |
Andre Noll | 6283815 | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 332 | printk("linear_make_request: Sector %llu out of bounds on " |
| 333 | "dev %s: %llu sectors, offset %llu\n", |
| 334 | (unsigned long long)bio->bi_sector, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 335 | bdevname(tmp_dev->rdev->bdev, b), |
Andre Noll | 6283815 | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 336 | (unsigned long long)tmp_dev->num_sectors, |
| 337 | (unsigned long long)tmp_dev->start_sector); |
NeilBrown | 6712ecf | 2007-09-27 12:47:43 +0200 | [diff] [blame] | 338 | bio_io_error(bio); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 339 | return 0; |
| 340 | } |
| 341 | if (unlikely(bio->bi_sector + (bio->bi_size >> 9) > |
Andre Noll | 6283815 | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 342 | tmp_dev->start_sector + tmp_dev->num_sectors)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 343 | /* This bio crosses a device boundary, so we have to |
| 344 | * split it. |
| 345 | */ |
| 346 | struct bio_pair *bp; |
Andre Noll | 6283815 | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 347 | |
Denis ChengRq | 6feef53 | 2008-10-09 08:57:05 +0200 | [diff] [blame] | 348 | bp = bio_split(bio, |
Andre Noll | 6283815 | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 349 | tmp_dev->start_sector + tmp_dev->num_sectors |
| 350 | - bio->bi_sector); |
| 351 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 352 | if (linear_make_request(q, &bp->bio1)) |
| 353 | generic_make_request(&bp->bio1); |
| 354 | if (linear_make_request(q, &bp->bio2)) |
| 355 | generic_make_request(&bp->bio2); |
| 356 | bio_pair_release(bp); |
| 357 | return 0; |
| 358 | } |
| 359 | |
| 360 | bio->bi_bdev = tmp_dev->rdev->bdev; |
Andre Noll | 6283815 | 2008-10-13 11:55:12 +1100 | [diff] [blame] | 361 | bio->bi_sector = bio->bi_sector - tmp_dev->start_sector |
| 362 | + tmp_dev->rdev->data_offset; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 363 | |
| 364 | return 1; |
| 365 | } |
| 366 | |
| 367 | static void linear_status (struct seq_file *seq, mddev_t *mddev) |
| 368 | { |
| 369 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 370 | seq_printf(seq, " %dk rounding", mddev->chunk_size/1024); |
| 371 | } |
| 372 | |
| 373 | |
NeilBrown | 2604b70 | 2006-01-06 00:20:36 -0800 | [diff] [blame] | 374 | static struct mdk_personality linear_personality = |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 375 | { |
| 376 | .name = "linear", |
NeilBrown | 2604b70 | 2006-01-06 00:20:36 -0800 | [diff] [blame] | 377 | .level = LEVEL_LINEAR, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 378 | .owner = THIS_MODULE, |
| 379 | .make_request = linear_make_request, |
| 380 | .run = linear_run, |
| 381 | .stop = linear_stop, |
| 382 | .status = linear_status, |
NeilBrown | 7c7546c | 2006-06-26 00:27:41 -0700 | [diff] [blame] | 383 | .hot_add_disk = linear_add, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 384 | }; |
| 385 | |
| 386 | static int __init linear_init (void) |
| 387 | { |
NeilBrown | 2604b70 | 2006-01-06 00:20:36 -0800 | [diff] [blame] | 388 | return register_md_personality (&linear_personality); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 389 | } |
| 390 | |
| 391 | static void linear_exit (void) |
| 392 | { |
NeilBrown | 2604b70 | 2006-01-06 00:20:36 -0800 | [diff] [blame] | 393 | unregister_md_personality (&linear_personality); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 394 | } |
| 395 | |
| 396 | |
| 397 | module_init(linear_init); |
| 398 | module_exit(linear_exit); |
| 399 | MODULE_LICENSE("GPL"); |
NeilBrown | d9d166c | 2006-01-06 00:20:51 -0800 | [diff] [blame] | 400 | MODULE_ALIAS("md-personality-1"); /* LINEAR - deprecated*/ |
| 401 | MODULE_ALIAS("md-linear"); |
NeilBrown | 2604b70 | 2006-01-06 00:20:36 -0800 | [diff] [blame] | 402 | MODULE_ALIAS("md-level--1"); |