Commit | Line | Data |
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1da177e4 LT |
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. | |
f72ffdd6 | 13 | |
1da177e4 LT |
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 | |
f72ffdd6 | 16 | Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
1da177e4 LT |
17 | */ |
18 | ||
bff61975 N |
19 | #include <linux/blkdev.h> |
20 | #include <linux/raid/md_u.h> | |
bff61975 | 21 | #include <linux/seq_file.h> |
056075c7 | 22 | #include <linux/module.h> |
5a0e3ad6 | 23 | #include <linux/slab.h> |
109e3765 | 24 | #include <trace/events/block.h> |
43b2e5d8 | 25 | #include "md.h" |
ef740c37 | 26 | #include "linear.h" |
1da177e4 | 27 | |
1da177e4 | 28 | /* |
f72ffdd6 | 29 | * find which device holds a particular offset |
1da177e4 | 30 | */ |
a7120771 | 31 | static inline struct dev_info *which_dev(struct mddev *mddev, sector_t sector) |
1da177e4 | 32 | { |
aece3d1f | 33 | int lo, mid, hi; |
e849b938 | 34 | struct linear_conf *conf; |
1da177e4 | 35 | |
aece3d1f SS |
36 | lo = 0; |
37 | hi = mddev->raid_disks - 1; | |
3be260cc | 38 | conf = mddev->private; |
1da177e4 | 39 | |
aece3d1f SS |
40 | /* |
41 | * Binary Search | |
42 | */ | |
43 | ||
44 | while (hi > lo) { | |
45 | ||
46 | mid = (hi + lo) / 2; | |
47 | if (sector < conf->disks[mid].end_sector) | |
48 | hi = mid; | |
49 | else | |
50 | lo = mid + 1; | |
51 | } | |
52 | ||
53 | return conf->disks + lo; | |
1da177e4 LT |
54 | } |
55 | ||
5c675f83 | 56 | static int linear_congested(struct mddev *mddev, int bits) |
26be34dc | 57 | { |
e849b938 | 58 | struct linear_conf *conf; |
26be34dc N |
59 | int i, ret = 0; |
60 | ||
3be260cc | 61 | conf = mddev->private; |
af11c397 | 62 | |
26be34dc | 63 | for (i = 0; i < mddev->raid_disks && !ret ; i++) { |
165125e1 | 64 | struct request_queue *q = bdev_get_queue(conf->disks[i].rdev->bdev); |
26be34dc N |
65 | ret |= bdi_congested(&q->backing_dev_info, bits); |
66 | } | |
af11c397 | 67 | |
26be34dc N |
68 | return ret; |
69 | } | |
70 | ||
fd01b88c | 71 | static sector_t linear_size(struct mddev *mddev, sector_t sectors, int raid_disks) |
80c3a6ce | 72 | { |
e849b938 | 73 | struct linear_conf *conf; |
af11c397 | 74 | sector_t array_sectors; |
80c3a6ce | 75 | |
3be260cc | 76 | conf = mddev->private; |
80c3a6ce DW |
77 | WARN_ONCE(sectors || raid_disks, |
78 | "%s does not support generic reshape\n", __func__); | |
af11c397 | 79 | array_sectors = conf->array_sectors; |
80c3a6ce | 80 | |
af11c397 | 81 | return array_sectors; |
80c3a6ce DW |
82 | } |
83 | ||
e849b938 | 84 | static struct linear_conf *linear_conf(struct mddev *mddev, int raid_disks) |
1da177e4 | 85 | { |
e849b938 | 86 | struct linear_conf *conf; |
3cb03002 | 87 | struct md_rdev *rdev; |
45d4582f | 88 | int i, cnt; |
f1cad2b6 | 89 | bool discard_supported = false; |
1da177e4 | 90 | |
a7120771 | 91 | conf = kzalloc (sizeof (*conf) + raid_disks*sizeof(struct dev_info), |
1da177e4 LT |
92 | GFP_KERNEL); |
93 | if (!conf) | |
7c7546cc N |
94 | return NULL; |
95 | ||
1da177e4 | 96 | cnt = 0; |
d6e22150 | 97 | conf->array_sectors = 0; |
1da177e4 | 98 | |
dafb20fa | 99 | rdev_for_each(rdev, mddev) { |
1da177e4 | 100 | int j = rdev->raid_disk; |
a7120771 | 101 | struct dev_info *disk = conf->disks + j; |
13f2682b | 102 | sector_t sectors; |
1da177e4 | 103 | |
13864515 | 104 | if (j < 0 || j >= raid_disks || disk->rdev) { |
a2e202af N |
105 | pr_warn("md/linear:%s: disk numbering problem. Aborting!\n", |
106 | mdname(mddev)); | |
1da177e4 LT |
107 | goto out; |
108 | } | |
109 | ||
110 | disk->rdev = rdev; | |
13f2682b N |
111 | if (mddev->chunk_sectors) { |
112 | sectors = rdev->sectors; | |
113 | sector_div(sectors, mddev->chunk_sectors); | |
114 | rdev->sectors = sectors * mddev->chunk_sectors; | |
115 | } | |
1da177e4 | 116 | |
8f6c2e4b MP |
117 | disk_stack_limits(mddev->gendisk, rdev->bdev, |
118 | rdev->data_offset << 9); | |
1da177e4 | 119 | |
dd8ac336 | 120 | conf->array_sectors += rdev->sectors; |
1da177e4 | 121 | cnt++; |
4db7cdc8 | 122 | |
f1cad2b6 SL |
123 | if (blk_queue_discard(bdev_get_queue(rdev->bdev))) |
124 | discard_supported = true; | |
1da177e4 | 125 | } |
7c7546cc | 126 | if (cnt != raid_disks) { |
a2e202af N |
127 | pr_warn("md/linear:%s: not enough drives present. Aborting!\n", |
128 | mdname(mddev)); | |
1da177e4 LT |
129 | goto out; |
130 | } | |
131 | ||
f1cad2b6 SL |
132 | if (!discard_supported) |
133 | queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, mddev->queue); | |
134 | else | |
135 | queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mddev->queue); | |
136 | ||
1da177e4 | 137 | /* |
45d4582f | 138 | * Here we calculate the device offsets. |
1da177e4 | 139 | */ |
4db7cdc8 SS |
140 | conf->disks[0].end_sector = conf->disks[0].rdev->sectors; |
141 | ||
a778b73f | 142 | for (i = 1; i < raid_disks; i++) |
4db7cdc8 SS |
143 | conf->disks[i].end_sector = |
144 | conf->disks[i-1].end_sector + | |
145 | conf->disks[i].rdev->sectors; | |
15945fee | 146 | |
7c7546cc N |
147 | return conf; |
148 | ||
149 | out: | |
150 | kfree(conf); | |
151 | return NULL; | |
152 | } | |
153 | ||
fd01b88c | 154 | static int linear_run (struct mddev *mddev) |
7c7546cc | 155 | { |
e849b938 | 156 | struct linear_conf *conf; |
98d5561b | 157 | int ret; |
7c7546cc | 158 | |
0894cc30 AN |
159 | if (md_check_no_bitmap(mddev)) |
160 | return -EINVAL; | |
7c7546cc N |
161 | conf = linear_conf(mddev, mddev->raid_disks); |
162 | ||
163 | if (!conf) | |
164 | return 1; | |
165 | mddev->private = conf; | |
1f403624 | 166 | md_set_array_sectors(mddev, linear_size(mddev, 0, 0)); |
7c7546cc | 167 | |
98d5561b | 168 | ret = md_integrity_register(mddev); |
169 | if (ret) { | |
170 | kfree(conf); | |
171 | mddev->private = NULL; | |
172 | } | |
173 | return ret; | |
7c7546cc | 174 | } |
1da177e4 | 175 | |
fd01b88c | 176 | static int linear_add(struct mddev *mddev, struct md_rdev *rdev) |
7c7546cc N |
177 | { |
178 | /* Adding a drive to a linear array allows the array to grow. | |
179 | * It is permitted if the new drive has a matching superblock | |
180 | * already on it, with raid_disk equal to raid_disks. | |
181 | * It is achieved by creating a new linear_private_data structure | |
182 | * and swapping it in in-place of the current one. | |
183 | * The current one is never freed until the array is stopped. | |
184 | * This avoids races. | |
185 | */ | |
e849b938 | 186 | struct linear_conf *newconf, *oldconf; |
7c7546cc | 187 | |
a778b73f | 188 | if (rdev->saved_raid_disk != mddev->raid_disks) |
7c7546cc N |
189 | return -EINVAL; |
190 | ||
a778b73f | 191 | rdev->raid_disk = rdev->saved_raid_disk; |
09cd9270 | 192 | rdev->saved_raid_disk = -1; |
a778b73f | 193 | |
7c7546cc N |
194 | newconf = linear_conf(mddev,mddev->raid_disks+1); |
195 | ||
196 | if (!newconf) | |
197 | return -ENOMEM; | |
198 | ||
3be260cc N |
199 | mddev_suspend(mddev); |
200 | oldconf = mddev->private; | |
7c7546cc | 201 | mddev->raid_disks++; |
3be260cc | 202 | mddev->private = newconf; |
1f403624 | 203 | md_set_array_sectors(mddev, linear_size(mddev, 0, 0)); |
f233ea5c | 204 | set_capacity(mddev->gendisk, mddev->array_sectors); |
3be260cc | 205 | mddev_resume(mddev); |
449aad3e | 206 | revalidate_disk(mddev->gendisk); |
3be260cc | 207 | kfree(oldconf); |
7c7546cc | 208 | return 0; |
1da177e4 LT |
209 | } |
210 | ||
afa0f557 | 211 | static void linear_free(struct mddev *mddev, void *priv) |
1da177e4 | 212 | { |
afa0f557 | 213 | struct linear_conf *conf = priv; |
af11c397 | 214 | |
495d3573 | 215 | kfree(conf); |
1da177e4 LT |
216 | } |
217 | ||
b4fdcb02 | 218 | static void linear_make_request(struct mddev *mddev, struct bio *bio) |
1da177e4 | 219 | { |
20d0189b | 220 | char b[BDEVNAME_SIZE]; |
a7120771 | 221 | struct dev_info *tmp_dev; |
20d0189b KO |
222 | struct bio *split; |
223 | sector_t start_sector, end_sector, data_offset; | |
1da177e4 | 224 | |
1eff9d32 | 225 | if (unlikely(bio->bi_opf & REQ_PREFLUSH)) { |
e9c7469b | 226 | md_flush_request(mddev, bio); |
5a7bbad2 | 227 | return; |
e5dcdd80 N |
228 | } |
229 | ||
20d0189b | 230 | do { |
109e3765 N |
231 | sector_t bio_sector = bio->bi_iter.bi_sector; |
232 | tmp_dev = which_dev(mddev, bio_sector); | |
20d0189b KO |
233 | start_sector = tmp_dev->end_sector - tmp_dev->rdev->sectors; |
234 | end_sector = tmp_dev->end_sector; | |
235 | data_offset = tmp_dev->rdev->data_offset; | |
236 | bio->bi_bdev = tmp_dev->rdev->bdev; | |
6283815d | 237 | |
109e3765 N |
238 | if (unlikely(bio_sector >= end_sector || |
239 | bio_sector < start_sector)) | |
20d0189b KO |
240 | goto out_of_bounds; |
241 | ||
242 | if (unlikely(bio_end_sector(bio) > end_sector)) { | |
243 | /* This bio crosses a device boundary, so we have to | |
244 | * split it. | |
245 | */ | |
109e3765 | 246 | split = bio_split(bio, end_sector - bio_sector, |
20d0189b KO |
247 | GFP_NOIO, fs_bio_set); |
248 | bio_chain(split, bio); | |
249 | } else { | |
250 | split = bio; | |
251 | } | |
f1cad2b6 | 252 | |
20d0189b KO |
253 | split->bi_iter.bi_sector = split->bi_iter.bi_sector - |
254 | start_sector + data_offset; | |
255 | ||
796a5cf0 | 256 | if (unlikely((bio_op(split) == REQ_OP_DISCARD) && |
20d0189b KO |
257 | !blk_queue_discard(bdev_get_queue(split->bi_bdev)))) { |
258 | /* Just ignore it */ | |
4246a0b6 | 259 | bio_endio(split); |
109e3765 N |
260 | } else { |
261 | if (mddev->gendisk) | |
262 | trace_block_bio_remap(bdev_get_queue(split->bi_bdev), | |
263 | split, disk_devt(mddev->gendisk), | |
264 | bio_sector); | |
20d0189b | 265 | generic_make_request(split); |
109e3765 | 266 | } |
20d0189b KO |
267 | } while (split != bio); |
268 | return; | |
269 | ||
270 | out_of_bounds: | |
a2e202af | 271 | pr_err("md/linear:%s: make_request: Sector %llu out of bounds on dev %s: %llu sectors, offset %llu\n", |
20d0189b KO |
272 | mdname(mddev), |
273 | (unsigned long long)bio->bi_iter.bi_sector, | |
274 | bdevname(tmp_dev->rdev->bdev, b), | |
275 | (unsigned long long)tmp_dev->rdev->sectors, | |
276 | (unsigned long long)start_sector); | |
277 | bio_io_error(bio); | |
1da177e4 LT |
278 | } |
279 | ||
fd01b88c | 280 | static void linear_status (struct seq_file *seq, struct mddev *mddev) |
1da177e4 | 281 | { |
9d8f0363 | 282 | seq_printf(seq, " %dk rounding", mddev->chunk_sectors / 2); |
1da177e4 LT |
283 | } |
284 | ||
3be260cc N |
285 | static void linear_quiesce(struct mddev *mddev, int state) |
286 | { | |
287 | } | |
288 | ||
84fc4b56 | 289 | static struct md_personality linear_personality = |
1da177e4 LT |
290 | { |
291 | .name = "linear", | |
2604b703 | 292 | .level = LEVEL_LINEAR, |
1da177e4 LT |
293 | .owner = THIS_MODULE, |
294 | .make_request = linear_make_request, | |
295 | .run = linear_run, | |
afa0f557 | 296 | .free = linear_free, |
1da177e4 | 297 | .status = linear_status, |
7c7546cc | 298 | .hot_add_disk = linear_add, |
80c3a6ce | 299 | .size = linear_size, |
3be260cc | 300 | .quiesce = linear_quiesce, |
5c675f83 | 301 | .congested = linear_congested, |
1da177e4 LT |
302 | }; |
303 | ||
304 | static int __init linear_init (void) | |
305 | { | |
2604b703 | 306 | return register_md_personality (&linear_personality); |
1da177e4 LT |
307 | } |
308 | ||
309 | static void linear_exit (void) | |
310 | { | |
2604b703 | 311 | unregister_md_personality (&linear_personality); |
1da177e4 LT |
312 | } |
313 | ||
1da177e4 LT |
314 | module_init(linear_init); |
315 | module_exit(linear_exit); | |
316 | MODULE_LICENSE("GPL"); | |
0efb9e61 | 317 | MODULE_DESCRIPTION("Linear device concatenation personality for MD"); |
d9d166c2 N |
318 | MODULE_ALIAS("md-personality-1"); /* LINEAR - deprecated*/ |
319 | MODULE_ALIAS("md-linear"); | |
2604b703 | 320 | MODULE_ALIAS("md-level--1"); |