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Commit | Line | Data |
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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 | ||
22 | #include <linux/module.h> | |
23 | #include <linux/slab.h> | |
24 | #include <linux/spinlock.h> | |
25 | #include <linux/raid/multipath.h> | |
26 | #include <linux/buffer_head.h> | |
27 | #include <asm/atomic.h> | |
28 | ||
29 | #define MAJOR_NR MD_MAJOR | |
30 | #define MD_DRIVER | |
31 | #define MD_PERSONALITY | |
32 | ||
33 | #define MAX_WORK_PER_DISK 128 | |
34 | ||
35 | #define NR_RESERVED_BUFS 32 | |
36 | ||
37 | ||
1da177e4 LT |
38 | static int multipath_map (multipath_conf_t *conf) |
39 | { | |
40 | int i, disks = conf->raid_disks; | |
41 | ||
42 | /* | |
43 | * Later we do read balancing on the read side | |
44 | * now we use the first available disk. | |
45 | */ | |
46 | ||
47 | rcu_read_lock(); | |
48 | for (i = 0; i < disks; i++) { | |
d6065f7b | 49 | mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev); |
b2d444d7 | 50 | if (rdev && test_bit(In_sync, &rdev->flags)) { |
1da177e4 LT |
51 | atomic_inc(&rdev->nr_pending); |
52 | rcu_read_unlock(); | |
53 | return i; | |
54 | } | |
55 | } | |
56 | rcu_read_unlock(); | |
57 | ||
58 | printk(KERN_ERR "multipath_map(): no more operational IO paths?\n"); | |
59 | return (-1); | |
60 | } | |
61 | ||
62 | static void multipath_reschedule_retry (struct multipath_bh *mp_bh) | |
63 | { | |
64 | unsigned long flags; | |
65 | mddev_t *mddev = mp_bh->mddev; | |
66 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
67 | ||
68 | spin_lock_irqsave(&conf->device_lock, flags); | |
69 | list_add(&mp_bh->retry_list, &conf->retry_list); | |
70 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
71 | md_wakeup_thread(mddev->thread); | |
72 | } | |
73 | ||
74 | ||
75 | /* | |
76 | * multipath_end_bh_io() is called when we have finished servicing a multipathed | |
77 | * operation and are ready to return a success/failure code to the buffer | |
78 | * cache layer. | |
79 | */ | |
80 | static void multipath_end_bh_io (struct multipath_bh *mp_bh, int err) | |
81 | { | |
82 | struct bio *bio = mp_bh->master_bio; | |
83 | multipath_conf_t *conf = mddev_to_conf(mp_bh->mddev); | |
84 | ||
6712ecf8 | 85 | bio_endio(bio, err); |
1da177e4 LT |
86 | mempool_free(mp_bh, conf->pool); |
87 | } | |
88 | ||
6712ecf8 | 89 | static void multipath_end_request(struct bio *bio, int error) |
1da177e4 LT |
90 | { |
91 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
92 | struct multipath_bh * mp_bh = (struct multipath_bh *)(bio->bi_private); | |
93 | multipath_conf_t *conf = mddev_to_conf(mp_bh->mddev); | |
94 | mdk_rdev_t *rdev = conf->multipaths[mp_bh->path].rdev; | |
95 | ||
1da177e4 LT |
96 | if (uptodate) |
97 | multipath_end_bh_io(mp_bh, 0); | |
98 | else if (!bio_rw_ahead(bio)) { | |
99 | /* | |
100 | * oops, IO error: | |
101 | */ | |
102 | char b[BDEVNAME_SIZE]; | |
103 | md_error (mp_bh->mddev, rdev); | |
104 | printk(KERN_ERR "multipath: %s: rescheduling sector %llu\n", | |
105 | bdevname(rdev->bdev,b), | |
106 | (unsigned long long)bio->bi_sector); | |
107 | multipath_reschedule_retry(mp_bh); | |
108 | } else | |
109 | multipath_end_bh_io(mp_bh, error); | |
110 | rdev_dec_pending(rdev, conf->mddev); | |
1da177e4 LT |
111 | } |
112 | ||
113 | static void unplug_slaves(mddev_t *mddev) | |
114 | { | |
115 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
116 | int i; | |
117 | ||
118 | rcu_read_lock(); | |
119 | for (i=0; i<mddev->raid_disks; i++) { | |
d6065f7b | 120 | mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev); |
b2d444d7 N |
121 | if (rdev && !test_bit(Faulty, &rdev->flags) |
122 | && atomic_read(&rdev->nr_pending)) { | |
165125e1 | 123 | struct request_queue *r_queue = bdev_get_queue(rdev->bdev); |
1da177e4 LT |
124 | |
125 | atomic_inc(&rdev->nr_pending); | |
126 | rcu_read_unlock(); | |
127 | ||
2ad8b1ef | 128 | blk_unplug(r_queue); |
1da177e4 LT |
129 | |
130 | rdev_dec_pending(rdev, mddev); | |
131 | rcu_read_lock(); | |
132 | } | |
133 | } | |
134 | rcu_read_unlock(); | |
135 | } | |
136 | ||
165125e1 | 137 | static void multipath_unplug(struct request_queue *q) |
1da177e4 LT |
138 | { |
139 | unplug_slaves(q->queuedata); | |
140 | } | |
141 | ||
142 | ||
165125e1 | 143 | static int multipath_make_request (struct request_queue *q, struct bio * bio) |
1da177e4 LT |
144 | { |
145 | mddev_t *mddev = q->queuedata; | |
146 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
147 | struct multipath_bh * mp_bh; | |
148 | struct multipath_info *multipath; | |
a362357b | 149 | const int rw = bio_data_dir(bio); |
1da177e4 | 150 | |
e5dcdd80 | 151 | if (unlikely(bio_barrier(bio))) { |
6712ecf8 | 152 | bio_endio(bio, -EOPNOTSUPP); |
e5dcdd80 N |
153 | return 0; |
154 | } | |
155 | ||
1da177e4 LT |
156 | mp_bh = mempool_alloc(conf->pool, GFP_NOIO); |
157 | ||
158 | mp_bh->master_bio = bio; | |
159 | mp_bh->mddev = mddev; | |
160 | ||
a362357b JA |
161 | disk_stat_inc(mddev->gendisk, ios[rw]); |
162 | disk_stat_add(mddev->gendisk, sectors[rw], bio_sectors(bio)); | |
1da177e4 LT |
163 | |
164 | mp_bh->path = multipath_map(conf); | |
165 | if (mp_bh->path < 0) { | |
6712ecf8 | 166 | bio_endio(bio, -EIO); |
1da177e4 LT |
167 | mempool_free(mp_bh, conf->pool); |
168 | return 0; | |
169 | } | |
170 | multipath = conf->multipaths + mp_bh->path; | |
171 | ||
172 | mp_bh->bio = *bio; | |
173 | mp_bh->bio.bi_sector += multipath->rdev->data_offset; | |
174 | mp_bh->bio.bi_bdev = multipath->rdev->bdev; | |
175 | mp_bh->bio.bi_rw |= (1 << BIO_RW_FAILFAST); | |
176 | mp_bh->bio.bi_end_io = multipath_end_request; | |
177 | mp_bh->bio.bi_private = mp_bh; | |
178 | generic_make_request(&mp_bh->bio); | |
179 | return 0; | |
180 | } | |
181 | ||
182 | static void multipath_status (struct seq_file *seq, mddev_t *mddev) | |
183 | { | |
184 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
185 | int i; | |
186 | ||
187 | seq_printf (seq, " [%d/%d] [", conf->raid_disks, | |
188 | conf->working_disks); | |
189 | for (i = 0; i < conf->raid_disks; i++) | |
190 | seq_printf (seq, "%s", | |
191 | conf->multipaths[i].rdev && | |
b2d444d7 | 192 | test_bit(In_sync, &conf->multipaths[i].rdev->flags) ? "U" : "_"); |
1da177e4 LT |
193 | seq_printf (seq, "]"); |
194 | } | |
195 | ||
0d129228 N |
196 | static int multipath_congested(void *data, int bits) |
197 | { | |
198 | mddev_t *mddev = data; | |
199 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
200 | int i, ret = 0; | |
201 | ||
202 | rcu_read_lock(); | |
203 | for (i = 0; i < mddev->raid_disks ; i++) { | |
204 | mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev); | |
205 | if (rdev && !test_bit(Faulty, &rdev->flags)) { | |
165125e1 | 206 | struct request_queue *q = bdev_get_queue(rdev->bdev); |
0d129228 N |
207 | |
208 | ret |= bdi_congested(&q->backing_dev_info, bits); | |
209 | /* Just like multipath_map, we just check the | |
210 | * first available device | |
211 | */ | |
212 | break; | |
213 | } | |
214 | } | |
215 | rcu_read_unlock(); | |
216 | return ret; | |
217 | } | |
1da177e4 LT |
218 | |
219 | /* | |
220 | * Careful, this can execute in IRQ contexts as well! | |
221 | */ | |
222 | static void multipath_error (mddev_t *mddev, mdk_rdev_t *rdev) | |
223 | { | |
224 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
225 | ||
226 | if (conf->working_disks <= 1) { | |
227 | /* | |
228 | * Uh oh, we can do nothing if this is our last path, but | |
229 | * first check if this is a queued request for a device | |
230 | * which has just failed. | |
231 | */ | |
232 | printk(KERN_ALERT | |
233 | "multipath: only one IO path left and IO error.\n"); | |
234 | /* leave it active... it's all we have */ | |
235 | } else { | |
236 | /* | |
237 | * Mark disk as unusable | |
238 | */ | |
b2d444d7 | 239 | if (!test_bit(Faulty, &rdev->flags)) { |
1da177e4 | 240 | char b[BDEVNAME_SIZE]; |
b2d444d7 N |
241 | clear_bit(In_sync, &rdev->flags); |
242 | set_bit(Faulty, &rdev->flags); | |
850b2b42 | 243 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
1da177e4 | 244 | conf->working_disks--; |
750a8f3e | 245 | mddev->degraded++; |
1da177e4 | 246 | printk(KERN_ALERT "multipath: IO failure on %s," |
d7a420c9 NA |
247 | " disabling IO path.\n" |
248 | "multipath: Operation continuing" | |
1da177e4 LT |
249 | " on %d IO paths.\n", |
250 | bdevname (rdev->bdev,b), | |
251 | conf->working_disks); | |
252 | } | |
253 | } | |
254 | } | |
255 | ||
256 | static void print_multipath_conf (multipath_conf_t *conf) | |
257 | { | |
258 | int i; | |
259 | struct multipath_info *tmp; | |
260 | ||
261 | printk("MULTIPATH conf printout:\n"); | |
262 | if (!conf) { | |
263 | printk("(conf==NULL)\n"); | |
264 | return; | |
265 | } | |
266 | printk(" --- wd:%d rd:%d\n", conf->working_disks, | |
267 | conf->raid_disks); | |
268 | ||
269 | for (i = 0; i < conf->raid_disks; i++) { | |
270 | char b[BDEVNAME_SIZE]; | |
271 | tmp = conf->multipaths + i; | |
272 | if (tmp->rdev) | |
273 | printk(" disk%d, o:%d, dev:%s\n", | |
b2d444d7 | 274 | i,!test_bit(Faulty, &tmp->rdev->flags), |
1da177e4 LT |
275 | bdevname(tmp->rdev->bdev,b)); |
276 | } | |
277 | } | |
278 | ||
279 | ||
280 | static int multipath_add_disk(mddev_t *mddev, mdk_rdev_t *rdev) | |
281 | { | |
282 | multipath_conf_t *conf = mddev->private; | |
352d768b | 283 | struct request_queue *q; |
199050ea | 284 | int err = -EEXIST; |
1da177e4 LT |
285 | int path; |
286 | struct multipath_info *p; | |
6c2fce2e NB |
287 | int first = 0; |
288 | int last = mddev->raid_disks - 1; | |
289 | ||
290 | if (rdev->raid_disk >= 0) | |
291 | first = last = rdev->raid_disk; | |
1da177e4 LT |
292 | |
293 | print_multipath_conf(conf); | |
294 | ||
6c2fce2e | 295 | for (path = first; path <= last; path++) |
1da177e4 | 296 | if ((p=conf->multipaths+path)->rdev == NULL) { |
352d768b JJ |
297 | q = rdev->bdev->bd_disk->queue; |
298 | blk_queue_stack_limits(mddev->queue, q); | |
1da177e4 LT |
299 | |
300 | /* as we don't honour merge_bvec_fn, we must never risk | |
301 | * violating it, so limit ->max_sector to one PAGE, as | |
302 | * a one page request is never in violation. | |
303 | * (Note: it is very unlikely that a device with | |
304 | * merge_bvec_fn will be involved in multipath.) | |
305 | */ | |
352d768b | 306 | if (q->merge_bvec_fn && |
1da177e4 LT |
307 | mddev->queue->max_sectors > (PAGE_SIZE>>9)) |
308 | blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9); | |
309 | ||
310 | conf->working_disks++; | |
750a8f3e | 311 | mddev->degraded--; |
1da177e4 | 312 | rdev->raid_disk = path; |
b2d444d7 | 313 | set_bit(In_sync, &rdev->flags); |
d6065f7b | 314 | rcu_assign_pointer(p->rdev, rdev); |
199050ea NB |
315 | err = 0; |
316 | break; | |
1da177e4 LT |
317 | } |
318 | ||
319 | print_multipath_conf(conf); | |
199050ea NB |
320 | |
321 | return err; | |
1da177e4 LT |
322 | } |
323 | ||
324 | static int multipath_remove_disk(mddev_t *mddev, int number) | |
325 | { | |
326 | multipath_conf_t *conf = mddev->private; | |
327 | int err = 0; | |
328 | mdk_rdev_t *rdev; | |
329 | struct multipath_info *p = conf->multipaths + number; | |
330 | ||
331 | print_multipath_conf(conf); | |
332 | ||
333 | rdev = p->rdev; | |
334 | if (rdev) { | |
b2d444d7 | 335 | if (test_bit(In_sync, &rdev->flags) || |
1da177e4 | 336 | atomic_read(&rdev->nr_pending)) { |
dfc70645 N |
337 | printk(KERN_ERR "hot-remove-disk, slot %d is identified" |
338 | " but is still operational!\n", number); | |
1da177e4 LT |
339 | err = -EBUSY; |
340 | goto abort; | |
341 | } | |
342 | p->rdev = NULL; | |
fbd568a3 | 343 | synchronize_rcu(); |
1da177e4 LT |
344 | if (atomic_read(&rdev->nr_pending)) { |
345 | /* lost the race, try later */ | |
346 | err = -EBUSY; | |
347 | p->rdev = rdev; | |
348 | } | |
349 | } | |
350 | abort: | |
351 | ||
352 | print_multipath_conf(conf); | |
353 | return err; | |
354 | } | |
355 | ||
356 | ||
357 | ||
358 | /* | |
359 | * This is a kernel thread which: | |
360 | * | |
361 | * 1. Retries failed read operations on working multipaths. | |
362 | * 2. Updates the raid superblock when problems encounter. | |
363 | * 3. Performs writes following reads for array syncronising. | |
364 | */ | |
365 | ||
366 | static void multipathd (mddev_t *mddev) | |
367 | { | |
368 | struct multipath_bh *mp_bh; | |
369 | struct bio *bio; | |
370 | unsigned long flags; | |
371 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
372 | struct list_head *head = &conf->retry_list; | |
373 | ||
374 | md_check_recovery(mddev); | |
375 | for (;;) { | |
376 | char b[BDEVNAME_SIZE]; | |
377 | spin_lock_irqsave(&conf->device_lock, flags); | |
378 | if (list_empty(head)) | |
379 | break; | |
380 | mp_bh = list_entry(head->prev, struct multipath_bh, retry_list); | |
381 | list_del(head->prev); | |
382 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
383 | ||
384 | bio = &mp_bh->bio; | |
385 | bio->bi_sector = mp_bh->master_bio->bi_sector; | |
386 | ||
387 | if ((mp_bh->path = multipath_map (conf))<0) { | |
388 | printk(KERN_ALERT "multipath: %s: unrecoverable IO read" | |
389 | " error for block %llu\n", | |
390 | bdevname(bio->bi_bdev,b), | |
391 | (unsigned long long)bio->bi_sector); | |
392 | multipath_end_bh_io(mp_bh, -EIO); | |
393 | } else { | |
394 | printk(KERN_ERR "multipath: %s: redirecting sector %llu" | |
395 | " to another IO path\n", | |
396 | bdevname(bio->bi_bdev,b), | |
397 | (unsigned long long)bio->bi_sector); | |
398 | *bio = *(mp_bh->master_bio); | |
399 | bio->bi_sector += conf->multipaths[mp_bh->path].rdev->data_offset; | |
400 | bio->bi_bdev = conf->multipaths[mp_bh->path].rdev->bdev; | |
401 | bio->bi_rw |= (1 << BIO_RW_FAILFAST); | |
402 | bio->bi_end_io = multipath_end_request; | |
403 | bio->bi_private = mp_bh; | |
404 | generic_make_request(bio); | |
405 | } | |
406 | } | |
407 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
408 | } | |
409 | ||
410 | static int multipath_run (mddev_t *mddev) | |
411 | { | |
412 | multipath_conf_t *conf; | |
413 | int disk_idx; | |
414 | struct multipath_info *disk; | |
415 | mdk_rdev_t *rdev; | |
416 | struct list_head *tmp; | |
417 | ||
418 | if (mddev->level != LEVEL_MULTIPATH) { | |
419 | printk("multipath: %s: raid level not set to multipath IO (%d)\n", | |
420 | mdname(mddev), mddev->level); | |
421 | goto out; | |
422 | } | |
423 | /* | |
424 | * copy the already verified devices into our private MULTIPATH | |
425 | * bookkeeping area. [whatever we allocate in multipath_run(), | |
426 | * should be freed in multipath_stop()] | |
427 | */ | |
e7e72bf6 | 428 | mddev->queue->queue_lock = &mddev->queue->__queue_lock; |
1da177e4 | 429 | |
9ffae0cf | 430 | conf = kzalloc(sizeof(multipath_conf_t), GFP_KERNEL); |
1da177e4 LT |
431 | mddev->private = conf; |
432 | if (!conf) { | |
433 | printk(KERN_ERR | |
434 | "multipath: couldn't allocate memory for %s\n", | |
435 | mdname(mddev)); | |
436 | goto out; | |
437 | } | |
1da177e4 | 438 | |
9ffae0cf | 439 | conf->multipaths = kzalloc(sizeof(struct multipath_info)*mddev->raid_disks, |
1da177e4 LT |
440 | GFP_KERNEL); |
441 | if (!conf->multipaths) { | |
442 | printk(KERN_ERR | |
443 | "multipath: couldn't allocate memory for %s\n", | |
444 | mdname(mddev)); | |
445 | goto out_free_conf; | |
446 | } | |
1da177e4 | 447 | |
1da177e4 | 448 | conf->working_disks = 0; |
d089c6af | 449 | rdev_for_each(rdev, tmp, mddev) { |
1da177e4 LT |
450 | disk_idx = rdev->raid_disk; |
451 | if (disk_idx < 0 || | |
452 | disk_idx >= mddev->raid_disks) | |
453 | continue; | |
454 | ||
455 | disk = conf->multipaths + disk_idx; | |
456 | disk->rdev = rdev; | |
457 | ||
458 | blk_queue_stack_limits(mddev->queue, | |
459 | rdev->bdev->bd_disk->queue); | |
460 | /* as we don't honour merge_bvec_fn, we must never risk | |
461 | * violating it, not that we ever expect a device with | |
462 | * a merge_bvec_fn to be involved in multipath */ | |
463 | if (rdev->bdev->bd_disk->queue->merge_bvec_fn && | |
464 | mddev->queue->max_sectors > (PAGE_SIZE>>9)) | |
465 | blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9); | |
466 | ||
b2d444d7 | 467 | if (!test_bit(Faulty, &rdev->flags)) |
1da177e4 LT |
468 | conf->working_disks++; |
469 | } | |
470 | ||
471 | conf->raid_disks = mddev->raid_disks; | |
1da177e4 LT |
472 | conf->mddev = mddev; |
473 | spin_lock_init(&conf->device_lock); | |
474 | INIT_LIST_HEAD(&conf->retry_list); | |
475 | ||
476 | if (!conf->working_disks) { | |
477 | printk(KERN_ERR "multipath: no operational IO paths for %s\n", | |
478 | mdname(mddev)); | |
479 | goto out_free_conf; | |
480 | } | |
2e333e89 | 481 | mddev->degraded = conf->raid_disks - conf->working_disks; |
1da177e4 | 482 | |
26b6e051 MD |
483 | conf->pool = mempool_create_kzalloc_pool(NR_RESERVED_BUFS, |
484 | sizeof(struct multipath_bh)); | |
1da177e4 LT |
485 | if (conf->pool == NULL) { |
486 | printk(KERN_ERR | |
487 | "multipath: couldn't allocate memory for %s\n", | |
488 | mdname(mddev)); | |
489 | goto out_free_conf; | |
490 | } | |
491 | ||
492 | { | |
493 | mddev->thread = md_register_thread(multipathd, mddev, "%s_multipath"); | |
494 | if (!mddev->thread) { | |
495 | printk(KERN_ERR "multipath: couldn't allocate thread" | |
496 | " for %s\n", mdname(mddev)); | |
497 | goto out_free_conf; | |
498 | } | |
499 | } | |
500 | ||
501 | printk(KERN_INFO | |
502 | "multipath: array %s active with %d out of %d IO paths\n", | |
503 | mdname(mddev), conf->working_disks, mddev->raid_disks); | |
504 | /* | |
505 | * Ok, everything is just fine now | |
506 | */ | |
f233ea5c | 507 | mddev->array_sectors = mddev->size * 2; |
7a5febe9 N |
508 | |
509 | mddev->queue->unplug_fn = multipath_unplug; | |
0d129228 N |
510 | mddev->queue->backing_dev_info.congested_fn = multipath_congested; |
511 | mddev->queue->backing_dev_info.congested_data = mddev; | |
7a5febe9 | 512 | |
1da177e4 LT |
513 | return 0; |
514 | ||
515 | out_free_conf: | |
516 | if (conf->pool) | |
517 | mempool_destroy(conf->pool); | |
990a8baf | 518 | kfree(conf->multipaths); |
1da177e4 LT |
519 | kfree(conf); |
520 | mddev->private = NULL; | |
521 | out: | |
522 | return -EIO; | |
523 | } | |
524 | ||
525 | ||
526 | static int multipath_stop (mddev_t *mddev) | |
527 | { | |
528 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
529 | ||
530 | md_unregister_thread(mddev->thread); | |
531 | mddev->thread = NULL; | |
532 | blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ | |
533 | mempool_destroy(conf->pool); | |
534 | kfree(conf->multipaths); | |
535 | kfree(conf); | |
536 | mddev->private = NULL; | |
537 | return 0; | |
538 | } | |
539 | ||
2604b703 | 540 | static struct mdk_personality multipath_personality = |
1da177e4 LT |
541 | { |
542 | .name = "multipath", | |
2604b703 | 543 | .level = LEVEL_MULTIPATH, |
1da177e4 LT |
544 | .owner = THIS_MODULE, |
545 | .make_request = multipath_make_request, | |
546 | .run = multipath_run, | |
547 | .stop = multipath_stop, | |
548 | .status = multipath_status, | |
549 | .error_handler = multipath_error, | |
550 | .hot_add_disk = multipath_add_disk, | |
551 | .hot_remove_disk= multipath_remove_disk, | |
552 | }; | |
553 | ||
554 | static int __init multipath_init (void) | |
555 | { | |
2604b703 | 556 | return register_md_personality (&multipath_personality); |
1da177e4 LT |
557 | } |
558 | ||
559 | static void __exit multipath_exit (void) | |
560 | { | |
2604b703 | 561 | unregister_md_personality (&multipath_personality); |
1da177e4 LT |
562 | } |
563 | ||
564 | module_init(multipath_init); | |
565 | module_exit(multipath_exit); | |
566 | MODULE_LICENSE("GPL"); | |
567 | MODULE_ALIAS("md-personality-7"); /* MULTIPATH */ | |
d9d166c2 | 568 | MODULE_ALIAS("md-multipath"); |
2604b703 | 569 | MODULE_ALIAS("md-level--4"); |