Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * multipath.c : Multiple Devices driver for Linux | |
3 | * | |
4 | * Copyright (C) 1999, 2000, 2001 Ingo Molnar, Red Hat | |
5 | * | |
6 | * Copyright (C) 1996, 1997, 1998 Ingo Molnar, Miguel de Icaza, Gadi Oxman | |
7 | * | |
8 | * MULTIPATH management functions. | |
9 | * | |
10 | * derived from raid1.c. | |
11 | * | |
12 | * This program is free software; you can redistribute it and/or modify | |
13 | * it under the terms of the GNU General Public License as published by | |
14 | * the Free Software Foundation; either version 2, or (at your option) | |
15 | * any later version. | |
16 | * | |
17 | * You should have received a copy of the GNU General Public License | |
18 | * (for example /usr/src/linux/COPYING); if not, write to the Free | |
19 | * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
20 | */ | |
21 | ||
bff61975 | 22 | #include <linux/blkdev.h> |
056075c7 | 23 | #include <linux/module.h> |
bff61975 | 24 | #include <linux/raid/md_u.h> |
bff61975 | 25 | #include <linux/seq_file.h> |
5a0e3ad6 | 26 | #include <linux/slab.h> |
43b2e5d8 | 27 | #include "md.h" |
ef740c37 | 28 | #include "multipath.h" |
1da177e4 LT |
29 | |
30 | #define MAX_WORK_PER_DISK 128 | |
31 | ||
32 | #define NR_RESERVED_BUFS 32 | |
33 | ||
34 | ||
69724e28 | 35 | static int multipath_map (struct mpconf *conf) |
1da177e4 LT |
36 | { |
37 | int i, disks = conf->raid_disks; | |
38 | ||
39 | /* | |
40 | * Later we do read balancing on the read side | |
41 | * now we use the first available disk. | |
42 | */ | |
43 | ||
44 | rcu_read_lock(); | |
45 | for (i = 0; i < disks; i++) { | |
3cb03002 | 46 | struct md_rdev *rdev = rcu_dereference(conf->multipaths[i].rdev); |
b2d444d7 | 47 | if (rdev && test_bit(In_sync, &rdev->flags)) { |
1da177e4 LT |
48 | atomic_inc(&rdev->nr_pending); |
49 | rcu_read_unlock(); | |
50 | return i; | |
51 | } | |
52 | } | |
53 | rcu_read_unlock(); | |
54 | ||
55 | printk(KERN_ERR "multipath_map(): no more operational IO paths?\n"); | |
56 | return (-1); | |
57 | } | |
58 | ||
59 | static void multipath_reschedule_retry (struct multipath_bh *mp_bh) | |
60 | { | |
61 | unsigned long flags; | |
fd01b88c | 62 | struct mddev *mddev = mp_bh->mddev; |
69724e28 | 63 | struct mpconf *conf = mddev->private; |
1da177e4 LT |
64 | |
65 | spin_lock_irqsave(&conf->device_lock, flags); | |
66 | list_add(&mp_bh->retry_list, &conf->retry_list); | |
67 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
68 | md_wakeup_thread(mddev->thread); | |
69 | } | |
70 | ||
71 | ||
72 | /* | |
73 | * multipath_end_bh_io() is called when we have finished servicing a multipathed | |
74 | * operation and are ready to return a success/failure code to the buffer | |
75 | * cache layer. | |
76 | */ | |
77 | static void multipath_end_bh_io (struct multipath_bh *mp_bh, int err) | |
78 | { | |
79 | struct bio *bio = mp_bh->master_bio; | |
69724e28 | 80 | struct mpconf *conf = mp_bh->mddev->private; |
1da177e4 | 81 | |
6712ecf8 | 82 | bio_endio(bio, err); |
1da177e4 LT |
83 | mempool_free(mp_bh, conf->pool); |
84 | } | |
85 | ||
6712ecf8 | 86 | static void multipath_end_request(struct bio *bio, int error) |
1da177e4 LT |
87 | { |
88 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
7b92813c | 89 | struct multipath_bh *mp_bh = bio->bi_private; |
69724e28 | 90 | struct mpconf *conf = mp_bh->mddev->private; |
3cb03002 | 91 | struct md_rdev *rdev = conf->multipaths[mp_bh->path].rdev; |
1da177e4 | 92 | |
1da177e4 LT |
93 | if (uptodate) |
94 | multipath_end_bh_io(mp_bh, 0); | |
7b6d91da | 95 | else if (!(bio->bi_rw & REQ_RAHEAD)) { |
1da177e4 LT |
96 | /* |
97 | * oops, IO error: | |
98 | */ | |
99 | char b[BDEVNAME_SIZE]; | |
100 | md_error (mp_bh->mddev, rdev); | |
101 | printk(KERN_ERR "multipath: %s: rescheduling sector %llu\n", | |
102 | bdevname(rdev->bdev,b), | |
103 | (unsigned long long)bio->bi_sector); | |
104 | multipath_reschedule_retry(mp_bh); | |
105 | } else | |
106 | multipath_end_bh_io(mp_bh, error); | |
107 | rdev_dec_pending(rdev, conf->mddev); | |
1da177e4 LT |
108 | } |
109 | ||
b4fdcb02 | 110 | static void multipath_make_request(struct mddev *mddev, struct bio * bio) |
1da177e4 | 111 | { |
69724e28 | 112 | struct mpconf *conf = mddev->private; |
1da177e4 LT |
113 | struct multipath_bh * mp_bh; |
114 | struct multipath_info *multipath; | |
115 | ||
e9c7469b TH |
116 | if (unlikely(bio->bi_rw & REQ_FLUSH)) { |
117 | md_flush_request(mddev, bio); | |
5a7bbad2 | 118 | return; |
e5dcdd80 N |
119 | } |
120 | ||
1da177e4 LT |
121 | mp_bh = mempool_alloc(conf->pool, GFP_NOIO); |
122 | ||
123 | mp_bh->master_bio = bio; | |
124 | mp_bh->mddev = mddev; | |
125 | ||
1da177e4 LT |
126 | mp_bh->path = multipath_map(conf); |
127 | if (mp_bh->path < 0) { | |
6712ecf8 | 128 | bio_endio(bio, -EIO); |
1da177e4 | 129 | mempool_free(mp_bh, conf->pool); |
5a7bbad2 | 130 | return; |
1da177e4 LT |
131 | } |
132 | multipath = conf->multipaths + mp_bh->path; | |
133 | ||
134 | mp_bh->bio = *bio; | |
135 | mp_bh->bio.bi_sector += multipath->rdev->data_offset; | |
136 | mp_bh->bio.bi_bdev = multipath->rdev->bdev; | |
7b6d91da | 137 | mp_bh->bio.bi_rw |= REQ_FAILFAST_TRANSPORT; |
1da177e4 LT |
138 | mp_bh->bio.bi_end_io = multipath_end_request; |
139 | mp_bh->bio.bi_private = mp_bh; | |
140 | generic_make_request(&mp_bh->bio); | |
5a7bbad2 | 141 | return; |
1da177e4 LT |
142 | } |
143 | ||
fd01b88c | 144 | static void multipath_status (struct seq_file *seq, struct mddev *mddev) |
1da177e4 | 145 | { |
69724e28 | 146 | struct mpconf *conf = mddev->private; |
1da177e4 LT |
147 | int i; |
148 | ||
149 | seq_printf (seq, " [%d/%d] [", conf->raid_disks, | |
92f861a7 | 150 | conf->raid_disks - mddev->degraded); |
1da177e4 LT |
151 | for (i = 0; i < conf->raid_disks; i++) |
152 | seq_printf (seq, "%s", | |
153 | conf->multipaths[i].rdev && | |
b2d444d7 | 154 | test_bit(In_sync, &conf->multipaths[i].rdev->flags) ? "U" : "_"); |
1da177e4 LT |
155 | seq_printf (seq, "]"); |
156 | } | |
157 | ||
0d129228 N |
158 | static int multipath_congested(void *data, int bits) |
159 | { | |
fd01b88c | 160 | struct mddev *mddev = data; |
69724e28 | 161 | struct mpconf *conf = mddev->private; |
0d129228 N |
162 | int i, ret = 0; |
163 | ||
3fa841d7 N |
164 | if (mddev_congested(mddev, bits)) |
165 | return 1; | |
166 | ||
0d129228 N |
167 | rcu_read_lock(); |
168 | for (i = 0; i < mddev->raid_disks ; i++) { | |
3cb03002 | 169 | struct md_rdev *rdev = rcu_dereference(conf->multipaths[i].rdev); |
0d129228 | 170 | if (rdev && !test_bit(Faulty, &rdev->flags)) { |
165125e1 | 171 | struct request_queue *q = bdev_get_queue(rdev->bdev); |
0d129228 N |
172 | |
173 | ret |= bdi_congested(&q->backing_dev_info, bits); | |
174 | /* Just like multipath_map, we just check the | |
175 | * first available device | |
176 | */ | |
177 | break; | |
178 | } | |
179 | } | |
180 | rcu_read_unlock(); | |
181 | return ret; | |
182 | } | |
1da177e4 LT |
183 | |
184 | /* | |
185 | * Careful, this can execute in IRQ contexts as well! | |
186 | */ | |
fd01b88c | 187 | static void multipath_error (struct mddev *mddev, struct md_rdev *rdev) |
1da177e4 | 188 | { |
69724e28 | 189 | struct mpconf *conf = mddev->private; |
6f8d0c77 | 190 | char b[BDEVNAME_SIZE]; |
1da177e4 | 191 | |
92f861a7 | 192 | if (conf->raid_disks - mddev->degraded <= 1) { |
1da177e4 LT |
193 | /* |
194 | * Uh oh, we can do nothing if this is our last path, but | |
195 | * first check if this is a queued request for a device | |
196 | * which has just failed. | |
197 | */ | |
198 | printk(KERN_ALERT | |
6f8d0c77 | 199 | "multipath: only one IO path left and IO error.\n"); |
1da177e4 | 200 | /* leave it active... it's all we have */ |
6f8d0c77 N |
201 | return; |
202 | } | |
203 | /* | |
204 | * Mark disk as unusable | |
205 | */ | |
206 | if (test_and_clear_bit(In_sync, &rdev->flags)) { | |
207 | unsigned long flags; | |
208 | spin_lock_irqsave(&conf->device_lock, flags); | |
209 | mddev->degraded++; | |
210 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
1da177e4 | 211 | } |
6f8d0c77 N |
212 | set_bit(Faulty, &rdev->flags); |
213 | set_bit(MD_CHANGE_DEVS, &mddev->flags); | |
214 | printk(KERN_ALERT "multipath: IO failure on %s," | |
215 | " disabling IO path.\n" | |
216 | "multipath: Operation continuing" | |
217 | " on %d IO paths.\n", | |
218 | bdevname(rdev->bdev, b), | |
219 | conf->raid_disks - mddev->degraded); | |
1da177e4 LT |
220 | } |
221 | ||
69724e28 | 222 | static void print_multipath_conf (struct mpconf *conf) |
1da177e4 LT |
223 | { |
224 | int i; | |
225 | struct multipath_info *tmp; | |
226 | ||
227 | printk("MULTIPATH conf printout:\n"); | |
228 | if (!conf) { | |
229 | printk("(conf==NULL)\n"); | |
230 | return; | |
231 | } | |
92f861a7 | 232 | printk(" --- wd:%d rd:%d\n", conf->raid_disks - conf->mddev->degraded, |
1da177e4 LT |
233 | conf->raid_disks); |
234 | ||
235 | for (i = 0; i < conf->raid_disks; i++) { | |
236 | char b[BDEVNAME_SIZE]; | |
237 | tmp = conf->multipaths + i; | |
238 | if (tmp->rdev) | |
239 | printk(" disk%d, o:%d, dev:%s\n", | |
b2d444d7 | 240 | i,!test_bit(Faulty, &tmp->rdev->flags), |
1da177e4 LT |
241 | bdevname(tmp->rdev->bdev,b)); |
242 | } | |
243 | } | |
244 | ||
245 | ||
fd01b88c | 246 | static int multipath_add_disk(struct mddev *mddev, struct md_rdev *rdev) |
1da177e4 | 247 | { |
69724e28 | 248 | struct mpconf *conf = mddev->private; |
352d768b | 249 | struct request_queue *q; |
199050ea | 250 | int err = -EEXIST; |
1da177e4 LT |
251 | int path; |
252 | struct multipath_info *p; | |
6c2fce2e NB |
253 | int first = 0; |
254 | int last = mddev->raid_disks - 1; | |
255 | ||
256 | if (rdev->raid_disk >= 0) | |
257 | first = last = rdev->raid_disk; | |
1da177e4 LT |
258 | |
259 | print_multipath_conf(conf); | |
260 | ||
6c2fce2e | 261 | for (path = first; path <= last; path++) |
1da177e4 | 262 | if ((p=conf->multipaths+path)->rdev == NULL) { |
352d768b | 263 | q = rdev->bdev->bd_disk->queue; |
8f6c2e4b MP |
264 | disk_stack_limits(mddev->gendisk, rdev->bdev, |
265 | rdev->data_offset << 9); | |
1da177e4 LT |
266 | |
267 | /* as we don't honour merge_bvec_fn, we must never risk | |
627a2d3c N |
268 | * violating it, so limit ->max_segments to one, lying |
269 | * within a single page. | |
1da177e4 LT |
270 | * (Note: it is very unlikely that a device with |
271 | * merge_bvec_fn will be involved in multipath.) | |
272 | */ | |
627a2d3c N |
273 | if (q->merge_bvec_fn) { |
274 | blk_queue_max_segments(mddev->queue, 1); | |
275 | blk_queue_segment_boundary(mddev->queue, | |
276 | PAGE_CACHE_SIZE - 1); | |
277 | } | |
1da177e4 | 278 | |
6f8d0c77 | 279 | spin_lock_irq(&conf->device_lock); |
750a8f3e | 280 | mddev->degraded--; |
1da177e4 | 281 | rdev->raid_disk = path; |
b2d444d7 | 282 | set_bit(In_sync, &rdev->flags); |
6f8d0c77 | 283 | spin_unlock_irq(&conf->device_lock); |
d6065f7b | 284 | rcu_assign_pointer(p->rdev, rdev); |
199050ea | 285 | err = 0; |
ac5e7113 | 286 | md_integrity_add_rdev(rdev, mddev); |
199050ea | 287 | break; |
1da177e4 LT |
288 | } |
289 | ||
290 | print_multipath_conf(conf); | |
199050ea NB |
291 | |
292 | return err; | |
1da177e4 LT |
293 | } |
294 | ||
b8321b68 | 295 | static int multipath_remove_disk(struct mddev *mddev, struct md_rdev *rdev) |
1da177e4 | 296 | { |
69724e28 | 297 | struct mpconf *conf = mddev->private; |
1da177e4 | 298 | int err = 0; |
b8321b68 | 299 | int number = rdev->raid_disk; |
1da177e4 LT |
300 | struct multipath_info *p = conf->multipaths + number; |
301 | ||
302 | print_multipath_conf(conf); | |
303 | ||
b8321b68 | 304 | if (rdev == p->rdev) { |
b2d444d7 | 305 | if (test_bit(In_sync, &rdev->flags) || |
1da177e4 | 306 | atomic_read(&rdev->nr_pending)) { |
dfc70645 N |
307 | printk(KERN_ERR "hot-remove-disk, slot %d is identified" |
308 | " but is still operational!\n", number); | |
1da177e4 LT |
309 | err = -EBUSY; |
310 | goto abort; | |
311 | } | |
312 | p->rdev = NULL; | |
fbd568a3 | 313 | synchronize_rcu(); |
1da177e4 LT |
314 | if (atomic_read(&rdev->nr_pending)) { |
315 | /* lost the race, try later */ | |
316 | err = -EBUSY; | |
317 | p->rdev = rdev; | |
ac5e7113 | 318 | goto abort; |
1da177e4 | 319 | } |
a91a2785 | 320 | err = md_integrity_register(mddev); |
1da177e4 LT |
321 | } |
322 | abort: | |
323 | ||
324 | print_multipath_conf(conf); | |
325 | return err; | |
326 | } | |
327 | ||
328 | ||
329 | ||
330 | /* | |
331 | * This is a kernel thread which: | |
332 | * | |
333 | * 1. Retries failed read operations on working multipaths. | |
334 | * 2. Updates the raid superblock when problems encounter. | |
335 | * 3. Performs writes following reads for array syncronising. | |
336 | */ | |
337 | ||
4ed8731d | 338 | static void multipathd(struct md_thread *thread) |
1da177e4 | 339 | { |
4ed8731d | 340 | struct mddev *mddev = thread->mddev; |
1da177e4 LT |
341 | struct multipath_bh *mp_bh; |
342 | struct bio *bio; | |
343 | unsigned long flags; | |
69724e28 | 344 | struct mpconf *conf = mddev->private; |
1da177e4 LT |
345 | struct list_head *head = &conf->retry_list; |
346 | ||
347 | md_check_recovery(mddev); | |
348 | for (;;) { | |
349 | char b[BDEVNAME_SIZE]; | |
350 | spin_lock_irqsave(&conf->device_lock, flags); | |
351 | if (list_empty(head)) | |
352 | break; | |
353 | mp_bh = list_entry(head->prev, struct multipath_bh, retry_list); | |
354 | list_del(head->prev); | |
355 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
356 | ||
357 | bio = &mp_bh->bio; | |
358 | bio->bi_sector = mp_bh->master_bio->bi_sector; | |
359 | ||
360 | if ((mp_bh->path = multipath_map (conf))<0) { | |
361 | printk(KERN_ALERT "multipath: %s: unrecoverable IO read" | |
362 | " error for block %llu\n", | |
363 | bdevname(bio->bi_bdev,b), | |
364 | (unsigned long long)bio->bi_sector); | |
365 | multipath_end_bh_io(mp_bh, -EIO); | |
366 | } else { | |
367 | printk(KERN_ERR "multipath: %s: redirecting sector %llu" | |
368 | " to another IO path\n", | |
369 | bdevname(bio->bi_bdev,b), | |
370 | (unsigned long long)bio->bi_sector); | |
371 | *bio = *(mp_bh->master_bio); | |
372 | bio->bi_sector += conf->multipaths[mp_bh->path].rdev->data_offset; | |
373 | bio->bi_bdev = conf->multipaths[mp_bh->path].rdev->bdev; | |
7b6d91da | 374 | bio->bi_rw |= REQ_FAILFAST_TRANSPORT; |
1da177e4 LT |
375 | bio->bi_end_io = multipath_end_request; |
376 | bio->bi_private = mp_bh; | |
377 | generic_make_request(bio); | |
378 | } | |
379 | } | |
380 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
381 | } | |
382 | ||
fd01b88c | 383 | static sector_t multipath_size(struct mddev *mddev, sector_t sectors, int raid_disks) |
80c3a6ce DW |
384 | { |
385 | WARN_ONCE(sectors || raid_disks, | |
386 | "%s does not support generic reshape\n", __func__); | |
387 | ||
388 | return mddev->dev_sectors; | |
389 | } | |
390 | ||
fd01b88c | 391 | static int multipath_run (struct mddev *mddev) |
1da177e4 | 392 | { |
69724e28 | 393 | struct mpconf *conf; |
1da177e4 LT |
394 | int disk_idx; |
395 | struct multipath_info *disk; | |
3cb03002 | 396 | struct md_rdev *rdev; |
92f861a7 | 397 | int working_disks; |
1da177e4 | 398 | |
0894cc30 AN |
399 | if (md_check_no_bitmap(mddev)) |
400 | return -EINVAL; | |
401 | ||
1da177e4 LT |
402 | if (mddev->level != LEVEL_MULTIPATH) { |
403 | printk("multipath: %s: raid level not set to multipath IO (%d)\n", | |
404 | mdname(mddev), mddev->level); | |
405 | goto out; | |
406 | } | |
407 | /* | |
408 | * copy the already verified devices into our private MULTIPATH | |
409 | * bookkeeping area. [whatever we allocate in multipath_run(), | |
410 | * should be freed in multipath_stop()] | |
411 | */ | |
412 | ||
69724e28 | 413 | conf = kzalloc(sizeof(struct mpconf), GFP_KERNEL); |
1da177e4 LT |
414 | mddev->private = conf; |
415 | if (!conf) { | |
416 | printk(KERN_ERR | |
417 | "multipath: couldn't allocate memory for %s\n", | |
418 | mdname(mddev)); | |
419 | goto out; | |
420 | } | |
1da177e4 | 421 | |
9ffae0cf | 422 | conf->multipaths = kzalloc(sizeof(struct multipath_info)*mddev->raid_disks, |
1da177e4 LT |
423 | GFP_KERNEL); |
424 | if (!conf->multipaths) { | |
425 | printk(KERN_ERR | |
426 | "multipath: couldn't allocate memory for %s\n", | |
427 | mdname(mddev)); | |
428 | goto out_free_conf; | |
429 | } | |
1da177e4 | 430 | |
92f861a7 | 431 | working_disks = 0; |
dafb20fa | 432 | rdev_for_each(rdev, mddev) { |
1da177e4 LT |
433 | disk_idx = rdev->raid_disk; |
434 | if (disk_idx < 0 || | |
435 | disk_idx >= mddev->raid_disks) | |
436 | continue; | |
437 | ||
438 | disk = conf->multipaths + disk_idx; | |
439 | disk->rdev = rdev; | |
8f6c2e4b MP |
440 | disk_stack_limits(mddev->gendisk, rdev->bdev, |
441 | rdev->data_offset << 9); | |
1da177e4 | 442 | |
1da177e4 LT |
443 | /* as we don't honour merge_bvec_fn, we must never risk |
444 | * violating it, not that we ever expect a device with | |
445 | * a merge_bvec_fn to be involved in multipath */ | |
627a2d3c N |
446 | if (rdev->bdev->bd_disk->queue->merge_bvec_fn) { |
447 | blk_queue_max_segments(mddev->queue, 1); | |
448 | blk_queue_segment_boundary(mddev->queue, | |
449 | PAGE_CACHE_SIZE - 1); | |
450 | } | |
1da177e4 | 451 | |
b2d444d7 | 452 | if (!test_bit(Faulty, &rdev->flags)) |
92f861a7 | 453 | working_disks++; |
1da177e4 LT |
454 | } |
455 | ||
456 | conf->raid_disks = mddev->raid_disks; | |
1da177e4 LT |
457 | conf->mddev = mddev; |
458 | spin_lock_init(&conf->device_lock); | |
459 | INIT_LIST_HEAD(&conf->retry_list); | |
460 | ||
92f861a7 | 461 | if (!working_disks) { |
1da177e4 LT |
462 | printk(KERN_ERR "multipath: no operational IO paths for %s\n", |
463 | mdname(mddev)); | |
464 | goto out_free_conf; | |
465 | } | |
92f861a7 | 466 | mddev->degraded = conf->raid_disks - working_disks; |
1da177e4 | 467 | |
bbba809e | 468 | conf->pool = mempool_create_kmalloc_pool(NR_RESERVED_BUFS, |
26b6e051 | 469 | sizeof(struct multipath_bh)); |
1da177e4 LT |
470 | if (conf->pool == NULL) { |
471 | printk(KERN_ERR | |
472 | "multipath: couldn't allocate memory for %s\n", | |
473 | mdname(mddev)); | |
474 | goto out_free_conf; | |
475 | } | |
476 | ||
477 | { | |
0232605d N |
478 | mddev->thread = md_register_thread(multipathd, mddev, |
479 | "multipath"); | |
1da177e4 LT |
480 | if (!mddev->thread) { |
481 | printk(KERN_ERR "multipath: couldn't allocate thread" | |
482 | " for %s\n", mdname(mddev)); | |
483 | goto out_free_conf; | |
484 | } | |
485 | } | |
486 | ||
487 | printk(KERN_INFO | |
488 | "multipath: array %s active with %d out of %d IO paths\n", | |
92f861a7 N |
489 | mdname(mddev), conf->raid_disks - mddev->degraded, |
490 | mddev->raid_disks); | |
1da177e4 LT |
491 | /* |
492 | * Ok, everything is just fine now | |
493 | */ | |
1f403624 | 494 | md_set_array_sectors(mddev, multipath_size(mddev, 0, 0)); |
7a5febe9 | 495 | |
0d129228 N |
496 | mddev->queue->backing_dev_info.congested_fn = multipath_congested; |
497 | mddev->queue->backing_dev_info.congested_data = mddev; | |
a91a2785 MP |
498 | |
499 | if (md_integrity_register(mddev)) | |
500 | goto out_free_conf; | |
501 | ||
1da177e4 LT |
502 | return 0; |
503 | ||
504 | out_free_conf: | |
505 | if (conf->pool) | |
506 | mempool_destroy(conf->pool); | |
990a8baf | 507 | kfree(conf->multipaths); |
1da177e4 LT |
508 | kfree(conf); |
509 | mddev->private = NULL; | |
510 | out: | |
511 | return -EIO; | |
512 | } | |
513 | ||
514 | ||
fd01b88c | 515 | static int multipath_stop (struct mddev *mddev) |
1da177e4 | 516 | { |
69724e28 | 517 | struct mpconf *conf = mddev->private; |
1da177e4 | 518 | |
01f96c0a | 519 | md_unregister_thread(&mddev->thread); |
1da177e4 LT |
520 | blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ |
521 | mempool_destroy(conf->pool); | |
522 | kfree(conf->multipaths); | |
523 | kfree(conf); | |
524 | mddev->private = NULL; | |
525 | return 0; | |
526 | } | |
527 | ||
84fc4b56 | 528 | static struct md_personality multipath_personality = |
1da177e4 LT |
529 | { |
530 | .name = "multipath", | |
2604b703 | 531 | .level = LEVEL_MULTIPATH, |
1da177e4 LT |
532 | .owner = THIS_MODULE, |
533 | .make_request = multipath_make_request, | |
534 | .run = multipath_run, | |
535 | .stop = multipath_stop, | |
536 | .status = multipath_status, | |
537 | .error_handler = multipath_error, | |
538 | .hot_add_disk = multipath_add_disk, | |
539 | .hot_remove_disk= multipath_remove_disk, | |
80c3a6ce | 540 | .size = multipath_size, |
1da177e4 LT |
541 | }; |
542 | ||
543 | static int __init multipath_init (void) | |
544 | { | |
2604b703 | 545 | return register_md_personality (&multipath_personality); |
1da177e4 LT |
546 | } |
547 | ||
548 | static void __exit multipath_exit (void) | |
549 | { | |
2604b703 | 550 | unregister_md_personality (&multipath_personality); |
1da177e4 LT |
551 | } |
552 | ||
553 | module_init(multipath_init); | |
554 | module_exit(multipath_exit); | |
555 | MODULE_LICENSE("GPL"); | |
0efb9e61 | 556 | MODULE_DESCRIPTION("simple multi-path personality for MD"); |
1da177e4 | 557 | MODULE_ALIAS("md-personality-7"); /* MULTIPATH */ |
d9d166c2 | 558 | MODULE_ALIAS("md-multipath"); |
2604b703 | 559 | MODULE_ALIAS("md-level--4"); |