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 | ||
1da177e4 | 22 | #include <linux/raid/multipath.h> |
1da177e4 LT |
23 | |
24 | #define MAX_WORK_PER_DISK 128 | |
25 | ||
26 | #define NR_RESERVED_BUFS 32 | |
27 | ||
28 | ||
1da177e4 LT |
29 | static int multipath_map (multipath_conf_t *conf) |
30 | { | |
31 | int i, disks = conf->raid_disks; | |
32 | ||
33 | /* | |
34 | * Later we do read balancing on the read side | |
35 | * now we use the first available disk. | |
36 | */ | |
37 | ||
38 | rcu_read_lock(); | |
39 | for (i = 0; i < disks; i++) { | |
d6065f7b | 40 | mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev); |
b2d444d7 | 41 | if (rdev && test_bit(In_sync, &rdev->flags)) { |
1da177e4 LT |
42 | atomic_inc(&rdev->nr_pending); |
43 | rcu_read_unlock(); | |
44 | return i; | |
45 | } | |
46 | } | |
47 | rcu_read_unlock(); | |
48 | ||
49 | printk(KERN_ERR "multipath_map(): no more operational IO paths?\n"); | |
50 | return (-1); | |
51 | } | |
52 | ||
53 | static void multipath_reschedule_retry (struct multipath_bh *mp_bh) | |
54 | { | |
55 | unsigned long flags; | |
56 | mddev_t *mddev = mp_bh->mddev; | |
57 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
58 | ||
59 | spin_lock_irqsave(&conf->device_lock, flags); | |
60 | list_add(&mp_bh->retry_list, &conf->retry_list); | |
61 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
62 | md_wakeup_thread(mddev->thread); | |
63 | } | |
64 | ||
65 | ||
66 | /* | |
67 | * multipath_end_bh_io() is called when we have finished servicing a multipathed | |
68 | * operation and are ready to return a success/failure code to the buffer | |
69 | * cache layer. | |
70 | */ | |
71 | static void multipath_end_bh_io (struct multipath_bh *mp_bh, int err) | |
72 | { | |
73 | struct bio *bio = mp_bh->master_bio; | |
74 | multipath_conf_t *conf = mddev_to_conf(mp_bh->mddev); | |
75 | ||
6712ecf8 | 76 | bio_endio(bio, err); |
1da177e4 LT |
77 | mempool_free(mp_bh, conf->pool); |
78 | } | |
79 | ||
6712ecf8 | 80 | static void multipath_end_request(struct bio *bio, int error) |
1da177e4 LT |
81 | { |
82 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
83 | struct multipath_bh * mp_bh = (struct multipath_bh *)(bio->bi_private); | |
84 | multipath_conf_t *conf = mddev_to_conf(mp_bh->mddev); | |
85 | mdk_rdev_t *rdev = conf->multipaths[mp_bh->path].rdev; | |
86 | ||
1da177e4 LT |
87 | if (uptodate) |
88 | multipath_end_bh_io(mp_bh, 0); | |
89 | else if (!bio_rw_ahead(bio)) { | |
90 | /* | |
91 | * oops, IO error: | |
92 | */ | |
93 | char b[BDEVNAME_SIZE]; | |
94 | md_error (mp_bh->mddev, rdev); | |
95 | printk(KERN_ERR "multipath: %s: rescheduling sector %llu\n", | |
96 | bdevname(rdev->bdev,b), | |
97 | (unsigned long long)bio->bi_sector); | |
98 | multipath_reschedule_retry(mp_bh); | |
99 | } else | |
100 | multipath_end_bh_io(mp_bh, error); | |
101 | rdev_dec_pending(rdev, conf->mddev); | |
1da177e4 LT |
102 | } |
103 | ||
104 | static void unplug_slaves(mddev_t *mddev) | |
105 | { | |
106 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
107 | int i; | |
108 | ||
109 | rcu_read_lock(); | |
110 | for (i=0; i<mddev->raid_disks; i++) { | |
d6065f7b | 111 | mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev); |
b2d444d7 N |
112 | if (rdev && !test_bit(Faulty, &rdev->flags) |
113 | && atomic_read(&rdev->nr_pending)) { | |
165125e1 | 114 | struct request_queue *r_queue = bdev_get_queue(rdev->bdev); |
1da177e4 LT |
115 | |
116 | atomic_inc(&rdev->nr_pending); | |
117 | rcu_read_unlock(); | |
118 | ||
2ad8b1ef | 119 | blk_unplug(r_queue); |
1da177e4 LT |
120 | |
121 | rdev_dec_pending(rdev, mddev); | |
122 | rcu_read_lock(); | |
123 | } | |
124 | } | |
125 | rcu_read_unlock(); | |
126 | } | |
127 | ||
165125e1 | 128 | static void multipath_unplug(struct request_queue *q) |
1da177e4 LT |
129 | { |
130 | unplug_slaves(q->queuedata); | |
131 | } | |
132 | ||
133 | ||
165125e1 | 134 | static int multipath_make_request (struct request_queue *q, struct bio * bio) |
1da177e4 LT |
135 | { |
136 | mddev_t *mddev = q->queuedata; | |
137 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
138 | struct multipath_bh * mp_bh; | |
139 | struct multipath_info *multipath; | |
a362357b | 140 | const int rw = bio_data_dir(bio); |
c9959059 | 141 | int cpu; |
1da177e4 | 142 | |
e5dcdd80 | 143 | if (unlikely(bio_barrier(bio))) { |
6712ecf8 | 144 | bio_endio(bio, -EOPNOTSUPP); |
e5dcdd80 N |
145 | return 0; |
146 | } | |
147 | ||
1da177e4 LT |
148 | mp_bh = mempool_alloc(conf->pool, GFP_NOIO); |
149 | ||
150 | mp_bh->master_bio = bio; | |
151 | mp_bh->mddev = mddev; | |
152 | ||
074a7aca TH |
153 | cpu = part_stat_lock(); |
154 | part_stat_inc(cpu, &mddev->gendisk->part0, ios[rw]); | |
155 | part_stat_add(cpu, &mddev->gendisk->part0, sectors[rw], | |
156 | bio_sectors(bio)); | |
157 | part_stat_unlock(); | |
1da177e4 LT |
158 | |
159 | mp_bh->path = multipath_map(conf); | |
160 | if (mp_bh->path < 0) { | |
6712ecf8 | 161 | bio_endio(bio, -EIO); |
1da177e4 LT |
162 | mempool_free(mp_bh, conf->pool); |
163 | return 0; | |
164 | } | |
165 | multipath = conf->multipaths + mp_bh->path; | |
166 | ||
167 | mp_bh->bio = *bio; | |
168 | mp_bh->bio.bi_sector += multipath->rdev->data_offset; | |
169 | mp_bh->bio.bi_bdev = multipath->rdev->bdev; | |
6000a368 | 170 | mp_bh->bio.bi_rw |= (1 << BIO_RW_FAILFAST_TRANSPORT); |
1da177e4 LT |
171 | mp_bh->bio.bi_end_io = multipath_end_request; |
172 | mp_bh->bio.bi_private = mp_bh; | |
173 | generic_make_request(&mp_bh->bio); | |
174 | return 0; | |
175 | } | |
176 | ||
177 | static void multipath_status (struct seq_file *seq, mddev_t *mddev) | |
178 | { | |
179 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
180 | int i; | |
181 | ||
182 | seq_printf (seq, " [%d/%d] [", conf->raid_disks, | |
183 | conf->working_disks); | |
184 | for (i = 0; i < conf->raid_disks; i++) | |
185 | seq_printf (seq, "%s", | |
186 | conf->multipaths[i].rdev && | |
b2d444d7 | 187 | test_bit(In_sync, &conf->multipaths[i].rdev->flags) ? "U" : "_"); |
1da177e4 LT |
188 | seq_printf (seq, "]"); |
189 | } | |
190 | ||
0d129228 N |
191 | static int multipath_congested(void *data, int bits) |
192 | { | |
193 | mddev_t *mddev = data; | |
194 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
195 | int i, ret = 0; | |
196 | ||
197 | rcu_read_lock(); | |
198 | for (i = 0; i < mddev->raid_disks ; i++) { | |
199 | mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev); | |
200 | if (rdev && !test_bit(Faulty, &rdev->flags)) { | |
165125e1 | 201 | struct request_queue *q = bdev_get_queue(rdev->bdev); |
0d129228 N |
202 | |
203 | ret |= bdi_congested(&q->backing_dev_info, bits); | |
204 | /* Just like multipath_map, we just check the | |
205 | * first available device | |
206 | */ | |
207 | break; | |
208 | } | |
209 | } | |
210 | rcu_read_unlock(); | |
211 | return ret; | |
212 | } | |
1da177e4 LT |
213 | |
214 | /* | |
215 | * Careful, this can execute in IRQ contexts as well! | |
216 | */ | |
217 | static void multipath_error (mddev_t *mddev, mdk_rdev_t *rdev) | |
218 | { | |
219 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
220 | ||
221 | if (conf->working_disks <= 1) { | |
222 | /* | |
223 | * Uh oh, we can do nothing if this is our last path, but | |
224 | * first check if this is a queued request for a device | |
225 | * which has just failed. | |
226 | */ | |
227 | printk(KERN_ALERT | |
228 | "multipath: only one IO path left and IO error.\n"); | |
229 | /* leave it active... it's all we have */ | |
230 | } else { | |
231 | /* | |
232 | * Mark disk as unusable | |
233 | */ | |
b2d444d7 | 234 | if (!test_bit(Faulty, &rdev->flags)) { |
1da177e4 | 235 | char b[BDEVNAME_SIZE]; |
b2d444d7 N |
236 | clear_bit(In_sync, &rdev->flags); |
237 | set_bit(Faulty, &rdev->flags); | |
850b2b42 | 238 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
1da177e4 | 239 | conf->working_disks--; |
750a8f3e | 240 | mddev->degraded++; |
1da177e4 | 241 | printk(KERN_ALERT "multipath: IO failure on %s," |
d7a420c9 NA |
242 | " disabling IO path.\n" |
243 | "multipath: Operation continuing" | |
1da177e4 LT |
244 | " on %d IO paths.\n", |
245 | bdevname (rdev->bdev,b), | |
246 | conf->working_disks); | |
247 | } | |
248 | } | |
249 | } | |
250 | ||
251 | static void print_multipath_conf (multipath_conf_t *conf) | |
252 | { | |
253 | int i; | |
254 | struct multipath_info *tmp; | |
255 | ||
256 | printk("MULTIPATH conf printout:\n"); | |
257 | if (!conf) { | |
258 | printk("(conf==NULL)\n"); | |
259 | return; | |
260 | } | |
261 | printk(" --- wd:%d rd:%d\n", conf->working_disks, | |
262 | conf->raid_disks); | |
263 | ||
264 | for (i = 0; i < conf->raid_disks; i++) { | |
265 | char b[BDEVNAME_SIZE]; | |
266 | tmp = conf->multipaths + i; | |
267 | if (tmp->rdev) | |
268 | printk(" disk%d, o:%d, dev:%s\n", | |
b2d444d7 | 269 | i,!test_bit(Faulty, &tmp->rdev->flags), |
1da177e4 LT |
270 | bdevname(tmp->rdev->bdev,b)); |
271 | } | |
272 | } | |
273 | ||
274 | ||
275 | static int multipath_add_disk(mddev_t *mddev, mdk_rdev_t *rdev) | |
276 | { | |
277 | multipath_conf_t *conf = mddev->private; | |
352d768b | 278 | struct request_queue *q; |
199050ea | 279 | int err = -EEXIST; |
1da177e4 LT |
280 | int path; |
281 | struct multipath_info *p; | |
6c2fce2e NB |
282 | int first = 0; |
283 | int last = mddev->raid_disks - 1; | |
284 | ||
285 | if (rdev->raid_disk >= 0) | |
286 | first = last = rdev->raid_disk; | |
1da177e4 LT |
287 | |
288 | print_multipath_conf(conf); | |
289 | ||
6c2fce2e | 290 | for (path = first; path <= last; path++) |
1da177e4 | 291 | if ((p=conf->multipaths+path)->rdev == NULL) { |
352d768b JJ |
292 | q = rdev->bdev->bd_disk->queue; |
293 | blk_queue_stack_limits(mddev->queue, q); | |
1da177e4 LT |
294 | |
295 | /* as we don't honour merge_bvec_fn, we must never risk | |
296 | * violating it, so limit ->max_sector to one PAGE, as | |
297 | * a one page request is never in violation. | |
298 | * (Note: it is very unlikely that a device with | |
299 | * merge_bvec_fn will be involved in multipath.) | |
300 | */ | |
352d768b | 301 | if (q->merge_bvec_fn && |
1da177e4 LT |
302 | mddev->queue->max_sectors > (PAGE_SIZE>>9)) |
303 | blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9); | |
304 | ||
305 | conf->working_disks++; | |
750a8f3e | 306 | mddev->degraded--; |
1da177e4 | 307 | rdev->raid_disk = path; |
b2d444d7 | 308 | set_bit(In_sync, &rdev->flags); |
d6065f7b | 309 | rcu_assign_pointer(p->rdev, rdev); |
199050ea NB |
310 | err = 0; |
311 | break; | |
1da177e4 LT |
312 | } |
313 | ||
314 | print_multipath_conf(conf); | |
199050ea NB |
315 | |
316 | return err; | |
1da177e4 LT |
317 | } |
318 | ||
319 | static int multipath_remove_disk(mddev_t *mddev, int number) | |
320 | { | |
321 | multipath_conf_t *conf = mddev->private; | |
322 | int err = 0; | |
323 | mdk_rdev_t *rdev; | |
324 | struct multipath_info *p = conf->multipaths + number; | |
325 | ||
326 | print_multipath_conf(conf); | |
327 | ||
328 | rdev = p->rdev; | |
329 | if (rdev) { | |
b2d444d7 | 330 | if (test_bit(In_sync, &rdev->flags) || |
1da177e4 | 331 | atomic_read(&rdev->nr_pending)) { |
dfc70645 N |
332 | printk(KERN_ERR "hot-remove-disk, slot %d is identified" |
333 | " but is still operational!\n", number); | |
1da177e4 LT |
334 | err = -EBUSY; |
335 | goto abort; | |
336 | } | |
337 | p->rdev = NULL; | |
fbd568a3 | 338 | synchronize_rcu(); |
1da177e4 LT |
339 | if (atomic_read(&rdev->nr_pending)) { |
340 | /* lost the race, try later */ | |
341 | err = -EBUSY; | |
342 | p->rdev = rdev; | |
343 | } | |
344 | } | |
345 | abort: | |
346 | ||
347 | print_multipath_conf(conf); | |
348 | return err; | |
349 | } | |
350 | ||
351 | ||
352 | ||
353 | /* | |
354 | * This is a kernel thread which: | |
355 | * | |
356 | * 1. Retries failed read operations on working multipaths. | |
357 | * 2. Updates the raid superblock when problems encounter. | |
358 | * 3. Performs writes following reads for array syncronising. | |
359 | */ | |
360 | ||
361 | static void multipathd (mddev_t *mddev) | |
362 | { | |
363 | struct multipath_bh *mp_bh; | |
364 | struct bio *bio; | |
365 | unsigned long flags; | |
366 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
367 | struct list_head *head = &conf->retry_list; | |
368 | ||
369 | md_check_recovery(mddev); | |
370 | for (;;) { | |
371 | char b[BDEVNAME_SIZE]; | |
372 | spin_lock_irqsave(&conf->device_lock, flags); | |
373 | if (list_empty(head)) | |
374 | break; | |
375 | mp_bh = list_entry(head->prev, struct multipath_bh, retry_list); | |
376 | list_del(head->prev); | |
377 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
378 | ||
379 | bio = &mp_bh->bio; | |
380 | bio->bi_sector = mp_bh->master_bio->bi_sector; | |
381 | ||
382 | if ((mp_bh->path = multipath_map (conf))<0) { | |
383 | printk(KERN_ALERT "multipath: %s: unrecoverable IO read" | |
384 | " error for block %llu\n", | |
385 | bdevname(bio->bi_bdev,b), | |
386 | (unsigned long long)bio->bi_sector); | |
387 | multipath_end_bh_io(mp_bh, -EIO); | |
388 | } else { | |
389 | printk(KERN_ERR "multipath: %s: redirecting sector %llu" | |
390 | " to another IO path\n", | |
391 | bdevname(bio->bi_bdev,b), | |
392 | (unsigned long long)bio->bi_sector); | |
393 | *bio = *(mp_bh->master_bio); | |
394 | bio->bi_sector += conf->multipaths[mp_bh->path].rdev->data_offset; | |
395 | bio->bi_bdev = conf->multipaths[mp_bh->path].rdev->bdev; | |
6000a368 | 396 | bio->bi_rw |= (1 << BIO_RW_FAILFAST_TRANSPORT); |
1da177e4 LT |
397 | bio->bi_end_io = multipath_end_request; |
398 | bio->bi_private = mp_bh; | |
399 | generic_make_request(bio); | |
400 | } | |
401 | } | |
402 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
403 | } | |
404 | ||
405 | static int multipath_run (mddev_t *mddev) | |
406 | { | |
407 | multipath_conf_t *conf; | |
408 | int disk_idx; | |
409 | struct multipath_info *disk; | |
410 | mdk_rdev_t *rdev; | |
411 | struct list_head *tmp; | |
412 | ||
413 | if (mddev->level != LEVEL_MULTIPATH) { | |
414 | printk("multipath: %s: raid level not set to multipath IO (%d)\n", | |
415 | mdname(mddev), mddev->level); | |
416 | goto out; | |
417 | } | |
418 | /* | |
419 | * copy the already verified devices into our private MULTIPATH | |
420 | * bookkeeping area. [whatever we allocate in multipath_run(), | |
421 | * should be freed in multipath_stop()] | |
422 | */ | |
e7e72bf6 | 423 | mddev->queue->queue_lock = &mddev->queue->__queue_lock; |
1da177e4 | 424 | |
9ffae0cf | 425 | conf = kzalloc(sizeof(multipath_conf_t), GFP_KERNEL); |
1da177e4 LT |
426 | mddev->private = conf; |
427 | if (!conf) { | |
428 | printk(KERN_ERR | |
429 | "multipath: couldn't allocate memory for %s\n", | |
430 | mdname(mddev)); | |
431 | goto out; | |
432 | } | |
1da177e4 | 433 | |
9ffae0cf | 434 | conf->multipaths = kzalloc(sizeof(struct multipath_info)*mddev->raid_disks, |
1da177e4 LT |
435 | GFP_KERNEL); |
436 | if (!conf->multipaths) { | |
437 | printk(KERN_ERR | |
438 | "multipath: couldn't allocate memory for %s\n", | |
439 | mdname(mddev)); | |
440 | goto out_free_conf; | |
441 | } | |
1da177e4 | 442 | |
1da177e4 | 443 | conf->working_disks = 0; |
d089c6af | 444 | rdev_for_each(rdev, tmp, mddev) { |
1da177e4 LT |
445 | disk_idx = rdev->raid_disk; |
446 | if (disk_idx < 0 || | |
447 | disk_idx >= mddev->raid_disks) | |
448 | continue; | |
449 | ||
450 | disk = conf->multipaths + disk_idx; | |
451 | disk->rdev = rdev; | |
452 | ||
453 | blk_queue_stack_limits(mddev->queue, | |
454 | rdev->bdev->bd_disk->queue); | |
455 | /* as we don't honour merge_bvec_fn, we must never risk | |
456 | * violating it, not that we ever expect a device with | |
457 | * a merge_bvec_fn to be involved in multipath */ | |
458 | if (rdev->bdev->bd_disk->queue->merge_bvec_fn && | |
459 | mddev->queue->max_sectors > (PAGE_SIZE>>9)) | |
460 | blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9); | |
461 | ||
b2d444d7 | 462 | if (!test_bit(Faulty, &rdev->flags)) |
1da177e4 LT |
463 | conf->working_disks++; |
464 | } | |
465 | ||
466 | conf->raid_disks = mddev->raid_disks; | |
1da177e4 LT |
467 | conf->mddev = mddev; |
468 | spin_lock_init(&conf->device_lock); | |
469 | INIT_LIST_HEAD(&conf->retry_list); | |
470 | ||
471 | if (!conf->working_disks) { | |
472 | printk(KERN_ERR "multipath: no operational IO paths for %s\n", | |
473 | mdname(mddev)); | |
474 | goto out_free_conf; | |
475 | } | |
2e333e89 | 476 | mddev->degraded = conf->raid_disks - conf->working_disks; |
1da177e4 | 477 | |
26b6e051 MD |
478 | conf->pool = mempool_create_kzalloc_pool(NR_RESERVED_BUFS, |
479 | sizeof(struct multipath_bh)); | |
1da177e4 LT |
480 | if (conf->pool == NULL) { |
481 | printk(KERN_ERR | |
482 | "multipath: couldn't allocate memory for %s\n", | |
483 | mdname(mddev)); | |
484 | goto out_free_conf; | |
485 | } | |
486 | ||
487 | { | |
488 | mddev->thread = md_register_thread(multipathd, mddev, "%s_multipath"); | |
489 | if (!mddev->thread) { | |
490 | printk(KERN_ERR "multipath: couldn't allocate thread" | |
491 | " for %s\n", mdname(mddev)); | |
492 | goto out_free_conf; | |
493 | } | |
494 | } | |
495 | ||
496 | printk(KERN_INFO | |
497 | "multipath: array %s active with %d out of %d IO paths\n", | |
498 | mdname(mddev), conf->working_disks, mddev->raid_disks); | |
499 | /* | |
500 | * Ok, everything is just fine now | |
501 | */ | |
f233ea5c | 502 | mddev->array_sectors = mddev->size * 2; |
7a5febe9 N |
503 | |
504 | mddev->queue->unplug_fn = multipath_unplug; | |
0d129228 N |
505 | mddev->queue->backing_dev_info.congested_fn = multipath_congested; |
506 | mddev->queue->backing_dev_info.congested_data = mddev; | |
7a5febe9 | 507 | |
1da177e4 LT |
508 | return 0; |
509 | ||
510 | out_free_conf: | |
511 | if (conf->pool) | |
512 | mempool_destroy(conf->pool); | |
990a8baf | 513 | kfree(conf->multipaths); |
1da177e4 LT |
514 | kfree(conf); |
515 | mddev->private = NULL; | |
516 | out: | |
517 | return -EIO; | |
518 | } | |
519 | ||
520 | ||
521 | static int multipath_stop (mddev_t *mddev) | |
522 | { | |
523 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
524 | ||
525 | md_unregister_thread(mddev->thread); | |
526 | mddev->thread = NULL; | |
527 | blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ | |
528 | mempool_destroy(conf->pool); | |
529 | kfree(conf->multipaths); | |
530 | kfree(conf); | |
531 | mddev->private = NULL; | |
532 | return 0; | |
533 | } | |
534 | ||
2604b703 | 535 | static struct mdk_personality multipath_personality = |
1da177e4 LT |
536 | { |
537 | .name = "multipath", | |
2604b703 | 538 | .level = LEVEL_MULTIPATH, |
1da177e4 LT |
539 | .owner = THIS_MODULE, |
540 | .make_request = multipath_make_request, | |
541 | .run = multipath_run, | |
542 | .stop = multipath_stop, | |
543 | .status = multipath_status, | |
544 | .error_handler = multipath_error, | |
545 | .hot_add_disk = multipath_add_disk, | |
546 | .hot_remove_disk= multipath_remove_disk, | |
547 | }; | |
548 | ||
549 | static int __init multipath_init (void) | |
550 | { | |
2604b703 | 551 | return register_md_personality (&multipath_personality); |
1da177e4 LT |
552 | } |
553 | ||
554 | static void __exit multipath_exit (void) | |
555 | { | |
2604b703 | 556 | unregister_md_personality (&multipath_personality); |
1da177e4 LT |
557 | } |
558 | ||
559 | module_init(multipath_init); | |
560 | module_exit(multipath_exit); | |
561 | MODULE_LICENSE("GPL"); | |
562 | MODULE_ALIAS("md-personality-7"); /* MULTIPATH */ | |
d9d166c2 | 563 | MODULE_ALIAS("md-multipath"); |
2604b703 | 564 | MODULE_ALIAS("md-level--4"); |