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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 | ||
85 | bio_endio(bio, bio->bi_size, err); | |
86 | mempool_free(mp_bh, conf->pool); | |
87 | } | |
88 | ||
75c96f85 AB |
89 | static int multipath_end_request(struct bio *bio, unsigned int bytes_done, |
90 | int error) | |
1da177e4 LT |
91 | { |
92 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
93 | struct multipath_bh * mp_bh = (struct multipath_bh *)(bio->bi_private); | |
94 | multipath_conf_t *conf = mddev_to_conf(mp_bh->mddev); | |
95 | mdk_rdev_t *rdev = conf->multipaths[mp_bh->path].rdev; | |
96 | ||
97 | if (bio->bi_size) | |
98 | return 1; | |
99 | ||
100 | if (uptodate) | |
101 | multipath_end_bh_io(mp_bh, 0); | |
102 | else if (!bio_rw_ahead(bio)) { | |
103 | /* | |
104 | * oops, IO error: | |
105 | */ | |
106 | char b[BDEVNAME_SIZE]; | |
107 | md_error (mp_bh->mddev, rdev); | |
108 | printk(KERN_ERR "multipath: %s: rescheduling sector %llu\n", | |
109 | bdevname(rdev->bdev,b), | |
110 | (unsigned long long)bio->bi_sector); | |
111 | multipath_reschedule_retry(mp_bh); | |
112 | } else | |
113 | multipath_end_bh_io(mp_bh, error); | |
114 | rdev_dec_pending(rdev, conf->mddev); | |
115 | return 0; | |
116 | } | |
117 | ||
118 | static void unplug_slaves(mddev_t *mddev) | |
119 | { | |
120 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
121 | int i; | |
122 | ||
123 | rcu_read_lock(); | |
124 | for (i=0; i<mddev->raid_disks; i++) { | |
d6065f7b | 125 | mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev); |
b2d444d7 N |
126 | if (rdev && !test_bit(Faulty, &rdev->flags) |
127 | && atomic_read(&rdev->nr_pending)) { | |
1da177e4 LT |
128 | request_queue_t *r_queue = bdev_get_queue(rdev->bdev); |
129 | ||
130 | atomic_inc(&rdev->nr_pending); | |
131 | rcu_read_unlock(); | |
132 | ||
133 | if (r_queue->unplug_fn) | |
134 | r_queue->unplug_fn(r_queue); | |
135 | ||
136 | rdev_dec_pending(rdev, mddev); | |
137 | rcu_read_lock(); | |
138 | } | |
139 | } | |
140 | rcu_read_unlock(); | |
141 | } | |
142 | ||
143 | static void multipath_unplug(request_queue_t *q) | |
144 | { | |
145 | unplug_slaves(q->queuedata); | |
146 | } | |
147 | ||
148 | ||
149 | static int multipath_make_request (request_queue_t *q, struct bio * bio) | |
150 | { | |
151 | mddev_t *mddev = q->queuedata; | |
152 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
153 | struct multipath_bh * mp_bh; | |
154 | struct multipath_info *multipath; | |
a362357b | 155 | const int rw = bio_data_dir(bio); |
1da177e4 | 156 | |
e5dcdd80 N |
157 | if (unlikely(bio_barrier(bio))) { |
158 | bio_endio(bio, bio->bi_size, -EOPNOTSUPP); | |
159 | return 0; | |
160 | } | |
161 | ||
1da177e4 LT |
162 | mp_bh = mempool_alloc(conf->pool, GFP_NOIO); |
163 | ||
164 | mp_bh->master_bio = bio; | |
165 | mp_bh->mddev = mddev; | |
166 | ||
a362357b JA |
167 | disk_stat_inc(mddev->gendisk, ios[rw]); |
168 | disk_stat_add(mddev->gendisk, sectors[rw], bio_sectors(bio)); | |
1da177e4 LT |
169 | |
170 | mp_bh->path = multipath_map(conf); | |
171 | if (mp_bh->path < 0) { | |
172 | bio_endio(bio, bio->bi_size, -EIO); | |
173 | mempool_free(mp_bh, conf->pool); | |
174 | return 0; | |
175 | } | |
176 | multipath = conf->multipaths + mp_bh->path; | |
177 | ||
178 | mp_bh->bio = *bio; | |
179 | mp_bh->bio.bi_sector += multipath->rdev->data_offset; | |
180 | mp_bh->bio.bi_bdev = multipath->rdev->bdev; | |
181 | mp_bh->bio.bi_rw |= (1 << BIO_RW_FAILFAST); | |
182 | mp_bh->bio.bi_end_io = multipath_end_request; | |
183 | mp_bh->bio.bi_private = mp_bh; | |
184 | generic_make_request(&mp_bh->bio); | |
185 | return 0; | |
186 | } | |
187 | ||
188 | static void multipath_status (struct seq_file *seq, mddev_t *mddev) | |
189 | { | |
190 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
191 | int i; | |
192 | ||
193 | seq_printf (seq, " [%d/%d] [", conf->raid_disks, | |
194 | conf->working_disks); | |
195 | for (i = 0; i < conf->raid_disks; i++) | |
196 | seq_printf (seq, "%s", | |
197 | conf->multipaths[i].rdev && | |
b2d444d7 | 198 | test_bit(In_sync, &conf->multipaths[i].rdev->flags) ? "U" : "_"); |
1da177e4 LT |
199 | seq_printf (seq, "]"); |
200 | } | |
201 | ||
202 | static int multipath_issue_flush(request_queue_t *q, struct gendisk *disk, | |
203 | sector_t *error_sector) | |
204 | { | |
205 | mddev_t *mddev = q->queuedata; | |
206 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
207 | int i, ret = 0; | |
208 | ||
209 | rcu_read_lock(); | |
210 | for (i=0; i<mddev->raid_disks && ret == 0; i++) { | |
d6065f7b | 211 | mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev); |
b2d444d7 | 212 | if (rdev && !test_bit(Faulty, &rdev->flags)) { |
1da177e4 LT |
213 | struct block_device *bdev = rdev->bdev; |
214 | request_queue_t *r_queue = bdev_get_queue(bdev); | |
215 | ||
216 | if (!r_queue->issue_flush_fn) | |
217 | ret = -EOPNOTSUPP; | |
218 | else { | |
219 | atomic_inc(&rdev->nr_pending); | |
220 | rcu_read_unlock(); | |
221 | ret = r_queue->issue_flush_fn(r_queue, bdev->bd_disk, | |
222 | error_sector); | |
223 | rdev_dec_pending(rdev, mddev); | |
224 | rcu_read_lock(); | |
225 | } | |
226 | } | |
227 | } | |
228 | rcu_read_unlock(); | |
229 | return ret; | |
230 | } | |
0d129228 N |
231 | static int multipath_congested(void *data, int bits) |
232 | { | |
233 | mddev_t *mddev = data; | |
234 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
235 | int i, ret = 0; | |
236 | ||
237 | rcu_read_lock(); | |
238 | for (i = 0; i < mddev->raid_disks ; i++) { | |
239 | mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev); | |
240 | if (rdev && !test_bit(Faulty, &rdev->flags)) { | |
241 | request_queue_t *q = bdev_get_queue(rdev->bdev); | |
242 | ||
243 | ret |= bdi_congested(&q->backing_dev_info, bits); | |
244 | /* Just like multipath_map, we just check the | |
245 | * first available device | |
246 | */ | |
247 | break; | |
248 | } | |
249 | } | |
250 | rcu_read_unlock(); | |
251 | return ret; | |
252 | } | |
1da177e4 LT |
253 | |
254 | /* | |
255 | * Careful, this can execute in IRQ contexts as well! | |
256 | */ | |
257 | static void multipath_error (mddev_t *mddev, mdk_rdev_t *rdev) | |
258 | { | |
259 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
260 | ||
261 | if (conf->working_disks <= 1) { | |
262 | /* | |
263 | * Uh oh, we can do nothing if this is our last path, but | |
264 | * first check if this is a queued request for a device | |
265 | * which has just failed. | |
266 | */ | |
267 | printk(KERN_ALERT | |
268 | "multipath: only one IO path left and IO error.\n"); | |
269 | /* leave it active... it's all we have */ | |
270 | } else { | |
271 | /* | |
272 | * Mark disk as unusable | |
273 | */ | |
b2d444d7 | 274 | if (!test_bit(Faulty, &rdev->flags)) { |
1da177e4 | 275 | char b[BDEVNAME_SIZE]; |
b2d444d7 N |
276 | clear_bit(In_sync, &rdev->flags); |
277 | set_bit(Faulty, &rdev->flags); | |
850b2b42 | 278 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
1da177e4 LT |
279 | conf->working_disks--; |
280 | printk(KERN_ALERT "multipath: IO failure on %s," | |
281 | " disabling IO path. \n Operation continuing" | |
282 | " on %d IO paths.\n", | |
283 | bdevname (rdev->bdev,b), | |
284 | conf->working_disks); | |
285 | } | |
286 | } | |
287 | } | |
288 | ||
289 | static void print_multipath_conf (multipath_conf_t *conf) | |
290 | { | |
291 | int i; | |
292 | struct multipath_info *tmp; | |
293 | ||
294 | printk("MULTIPATH conf printout:\n"); | |
295 | if (!conf) { | |
296 | printk("(conf==NULL)\n"); | |
297 | return; | |
298 | } | |
299 | printk(" --- wd:%d rd:%d\n", conf->working_disks, | |
300 | conf->raid_disks); | |
301 | ||
302 | for (i = 0; i < conf->raid_disks; i++) { | |
303 | char b[BDEVNAME_SIZE]; | |
304 | tmp = conf->multipaths + i; | |
305 | if (tmp->rdev) | |
306 | printk(" disk%d, o:%d, dev:%s\n", | |
b2d444d7 | 307 | i,!test_bit(Faulty, &tmp->rdev->flags), |
1da177e4 LT |
308 | bdevname(tmp->rdev->bdev,b)); |
309 | } | |
310 | } | |
311 | ||
312 | ||
313 | static int multipath_add_disk(mddev_t *mddev, mdk_rdev_t *rdev) | |
314 | { | |
315 | multipath_conf_t *conf = mddev->private; | |
352d768b | 316 | struct request_queue *q; |
1da177e4 LT |
317 | int found = 0; |
318 | int path; | |
319 | struct multipath_info *p; | |
320 | ||
321 | print_multipath_conf(conf); | |
322 | ||
323 | for (path=0; path<mddev->raid_disks; path++) | |
324 | if ((p=conf->multipaths+path)->rdev == NULL) { | |
352d768b JJ |
325 | q = rdev->bdev->bd_disk->queue; |
326 | blk_queue_stack_limits(mddev->queue, q); | |
1da177e4 LT |
327 | |
328 | /* as we don't honour merge_bvec_fn, we must never risk | |
329 | * violating it, so limit ->max_sector to one PAGE, as | |
330 | * a one page request is never in violation. | |
331 | * (Note: it is very unlikely that a device with | |
332 | * merge_bvec_fn will be involved in multipath.) | |
333 | */ | |
352d768b | 334 | if (q->merge_bvec_fn && |
1da177e4 LT |
335 | mddev->queue->max_sectors > (PAGE_SIZE>>9)) |
336 | blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9); | |
337 | ||
338 | conf->working_disks++; | |
339 | rdev->raid_disk = path; | |
b2d444d7 | 340 | set_bit(In_sync, &rdev->flags); |
d6065f7b | 341 | rcu_assign_pointer(p->rdev, rdev); |
1da177e4 LT |
342 | found = 1; |
343 | } | |
344 | ||
345 | print_multipath_conf(conf); | |
346 | return found; | |
347 | } | |
348 | ||
349 | static int multipath_remove_disk(mddev_t *mddev, int number) | |
350 | { | |
351 | multipath_conf_t *conf = mddev->private; | |
352 | int err = 0; | |
353 | mdk_rdev_t *rdev; | |
354 | struct multipath_info *p = conf->multipaths + number; | |
355 | ||
356 | print_multipath_conf(conf); | |
357 | ||
358 | rdev = p->rdev; | |
359 | if (rdev) { | |
b2d444d7 | 360 | if (test_bit(In_sync, &rdev->flags) || |
1da177e4 LT |
361 | atomic_read(&rdev->nr_pending)) { |
362 | printk(KERN_ERR "hot-remove-disk, slot %d is identified" " but is still operational!\n", number); | |
363 | err = -EBUSY; | |
364 | goto abort; | |
365 | } | |
366 | p->rdev = NULL; | |
fbd568a3 | 367 | synchronize_rcu(); |
1da177e4 LT |
368 | if (atomic_read(&rdev->nr_pending)) { |
369 | /* lost the race, try later */ | |
370 | err = -EBUSY; | |
371 | p->rdev = rdev; | |
372 | } | |
373 | } | |
374 | abort: | |
375 | ||
376 | print_multipath_conf(conf); | |
377 | return err; | |
378 | } | |
379 | ||
380 | ||
381 | ||
382 | /* | |
383 | * This is a kernel thread which: | |
384 | * | |
385 | * 1. Retries failed read operations on working multipaths. | |
386 | * 2. Updates the raid superblock when problems encounter. | |
387 | * 3. Performs writes following reads for array syncronising. | |
388 | */ | |
389 | ||
390 | static void multipathd (mddev_t *mddev) | |
391 | { | |
392 | struct multipath_bh *mp_bh; | |
393 | struct bio *bio; | |
394 | unsigned long flags; | |
395 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
396 | struct list_head *head = &conf->retry_list; | |
397 | ||
398 | md_check_recovery(mddev); | |
399 | for (;;) { | |
400 | char b[BDEVNAME_SIZE]; | |
401 | spin_lock_irqsave(&conf->device_lock, flags); | |
402 | if (list_empty(head)) | |
403 | break; | |
404 | mp_bh = list_entry(head->prev, struct multipath_bh, retry_list); | |
405 | list_del(head->prev); | |
406 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
407 | ||
408 | bio = &mp_bh->bio; | |
409 | bio->bi_sector = mp_bh->master_bio->bi_sector; | |
410 | ||
411 | if ((mp_bh->path = multipath_map (conf))<0) { | |
412 | printk(KERN_ALERT "multipath: %s: unrecoverable IO read" | |
413 | " error for block %llu\n", | |
414 | bdevname(bio->bi_bdev,b), | |
415 | (unsigned long long)bio->bi_sector); | |
416 | multipath_end_bh_io(mp_bh, -EIO); | |
417 | } else { | |
418 | printk(KERN_ERR "multipath: %s: redirecting sector %llu" | |
419 | " to another IO path\n", | |
420 | bdevname(bio->bi_bdev,b), | |
421 | (unsigned long long)bio->bi_sector); | |
422 | *bio = *(mp_bh->master_bio); | |
423 | bio->bi_sector += conf->multipaths[mp_bh->path].rdev->data_offset; | |
424 | bio->bi_bdev = conf->multipaths[mp_bh->path].rdev->bdev; | |
425 | bio->bi_rw |= (1 << BIO_RW_FAILFAST); | |
426 | bio->bi_end_io = multipath_end_request; | |
427 | bio->bi_private = mp_bh; | |
428 | generic_make_request(bio); | |
429 | } | |
430 | } | |
431 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
432 | } | |
433 | ||
434 | static int multipath_run (mddev_t *mddev) | |
435 | { | |
436 | multipath_conf_t *conf; | |
437 | int disk_idx; | |
438 | struct multipath_info *disk; | |
439 | mdk_rdev_t *rdev; | |
440 | struct list_head *tmp; | |
441 | ||
442 | if (mddev->level != LEVEL_MULTIPATH) { | |
443 | printk("multipath: %s: raid level not set to multipath IO (%d)\n", | |
444 | mdname(mddev), mddev->level); | |
445 | goto out; | |
446 | } | |
447 | /* | |
448 | * copy the already verified devices into our private MULTIPATH | |
449 | * bookkeeping area. [whatever we allocate in multipath_run(), | |
450 | * should be freed in multipath_stop()] | |
451 | */ | |
452 | ||
9ffae0cf | 453 | conf = kzalloc(sizeof(multipath_conf_t), GFP_KERNEL); |
1da177e4 LT |
454 | mddev->private = conf; |
455 | if (!conf) { | |
456 | printk(KERN_ERR | |
457 | "multipath: couldn't allocate memory for %s\n", | |
458 | mdname(mddev)); | |
459 | goto out; | |
460 | } | |
1da177e4 | 461 | |
9ffae0cf | 462 | conf->multipaths = kzalloc(sizeof(struct multipath_info)*mddev->raid_disks, |
1da177e4 LT |
463 | GFP_KERNEL); |
464 | if (!conf->multipaths) { | |
465 | printk(KERN_ERR | |
466 | "multipath: couldn't allocate memory for %s\n", | |
467 | mdname(mddev)); | |
468 | goto out_free_conf; | |
469 | } | |
1da177e4 | 470 | |
1da177e4 LT |
471 | conf->working_disks = 0; |
472 | ITERATE_RDEV(mddev,rdev,tmp) { | |
473 | disk_idx = rdev->raid_disk; | |
474 | if (disk_idx < 0 || | |
475 | disk_idx >= mddev->raid_disks) | |
476 | continue; | |
477 | ||
478 | disk = conf->multipaths + disk_idx; | |
479 | disk->rdev = rdev; | |
480 | ||
481 | blk_queue_stack_limits(mddev->queue, | |
482 | rdev->bdev->bd_disk->queue); | |
483 | /* as we don't honour merge_bvec_fn, we must never risk | |
484 | * violating it, not that we ever expect a device with | |
485 | * a merge_bvec_fn to be involved in multipath */ | |
486 | if (rdev->bdev->bd_disk->queue->merge_bvec_fn && | |
487 | mddev->queue->max_sectors > (PAGE_SIZE>>9)) | |
488 | blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9); | |
489 | ||
b2d444d7 | 490 | if (!test_bit(Faulty, &rdev->flags)) |
1da177e4 LT |
491 | conf->working_disks++; |
492 | } | |
493 | ||
494 | conf->raid_disks = mddev->raid_disks; | |
1da177e4 LT |
495 | conf->mddev = mddev; |
496 | spin_lock_init(&conf->device_lock); | |
497 | INIT_LIST_HEAD(&conf->retry_list); | |
498 | ||
499 | if (!conf->working_disks) { | |
500 | printk(KERN_ERR "multipath: no operational IO paths for %s\n", | |
501 | mdname(mddev)); | |
502 | goto out_free_conf; | |
503 | } | |
504 | mddev->degraded = conf->raid_disks = conf->working_disks; | |
505 | ||
26b6e051 MD |
506 | conf->pool = mempool_create_kzalloc_pool(NR_RESERVED_BUFS, |
507 | sizeof(struct multipath_bh)); | |
1da177e4 LT |
508 | if (conf->pool == NULL) { |
509 | printk(KERN_ERR | |
510 | "multipath: couldn't allocate memory for %s\n", | |
511 | mdname(mddev)); | |
512 | goto out_free_conf; | |
513 | } | |
514 | ||
515 | { | |
516 | mddev->thread = md_register_thread(multipathd, mddev, "%s_multipath"); | |
517 | if (!mddev->thread) { | |
518 | printk(KERN_ERR "multipath: couldn't allocate thread" | |
519 | " for %s\n", mdname(mddev)); | |
520 | goto out_free_conf; | |
521 | } | |
522 | } | |
523 | ||
524 | printk(KERN_INFO | |
525 | "multipath: array %s active with %d out of %d IO paths\n", | |
526 | mdname(mddev), conf->working_disks, mddev->raid_disks); | |
527 | /* | |
528 | * Ok, everything is just fine now | |
529 | */ | |
530 | mddev->array_size = mddev->size; | |
7a5febe9 N |
531 | |
532 | mddev->queue->unplug_fn = multipath_unplug; | |
533 | mddev->queue->issue_flush_fn = multipath_issue_flush; | |
0d129228 N |
534 | mddev->queue->backing_dev_info.congested_fn = multipath_congested; |
535 | mddev->queue->backing_dev_info.congested_data = mddev; | |
7a5febe9 | 536 | |
1da177e4 LT |
537 | return 0; |
538 | ||
539 | out_free_conf: | |
540 | if (conf->pool) | |
541 | mempool_destroy(conf->pool); | |
990a8baf | 542 | kfree(conf->multipaths); |
1da177e4 LT |
543 | kfree(conf); |
544 | mddev->private = NULL; | |
545 | out: | |
546 | return -EIO; | |
547 | } | |
548 | ||
549 | ||
550 | static int multipath_stop (mddev_t *mddev) | |
551 | { | |
552 | multipath_conf_t *conf = mddev_to_conf(mddev); | |
553 | ||
554 | md_unregister_thread(mddev->thread); | |
555 | mddev->thread = NULL; | |
556 | blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ | |
557 | mempool_destroy(conf->pool); | |
558 | kfree(conf->multipaths); | |
559 | kfree(conf); | |
560 | mddev->private = NULL; | |
561 | return 0; | |
562 | } | |
563 | ||
2604b703 | 564 | static struct mdk_personality multipath_personality = |
1da177e4 LT |
565 | { |
566 | .name = "multipath", | |
2604b703 | 567 | .level = LEVEL_MULTIPATH, |
1da177e4 LT |
568 | .owner = THIS_MODULE, |
569 | .make_request = multipath_make_request, | |
570 | .run = multipath_run, | |
571 | .stop = multipath_stop, | |
572 | .status = multipath_status, | |
573 | .error_handler = multipath_error, | |
574 | .hot_add_disk = multipath_add_disk, | |
575 | .hot_remove_disk= multipath_remove_disk, | |
576 | }; | |
577 | ||
578 | static int __init multipath_init (void) | |
579 | { | |
2604b703 | 580 | return register_md_personality (&multipath_personality); |
1da177e4 LT |
581 | } |
582 | ||
583 | static void __exit multipath_exit (void) | |
584 | { | |
2604b703 | 585 | unregister_md_personality (&multipath_personality); |
1da177e4 LT |
586 | } |
587 | ||
588 | module_init(multipath_init); | |
589 | module_exit(multipath_exit); | |
590 | MODULE_LICENSE("GPL"); | |
591 | MODULE_ALIAS("md-personality-7"); /* MULTIPATH */ | |
d9d166c2 | 592 | MODULE_ALIAS("md-multipath"); |
2604b703 | 593 | MODULE_ALIAS("md-level--4"); |