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 N |
22 | #include <linux/blkdev.h> |
23 | #include <linux/raid/md_u.h> | |
bff61975 | 24 | #include <linux/seq_file.h> |
5a0e3ad6 | 25 | #include <linux/slab.h> |
43b2e5d8 | 26 | #include "md.h" |
ef740c37 | 27 | #include "multipath.h" |
1da177e4 LT |
28 | |
29 | #define MAX_WORK_PER_DISK 128 | |
30 | ||
31 | #define NR_RESERVED_BUFS 32 | |
32 | ||
33 | ||
1da177e4 LT |
34 | static int multipath_map (multipath_conf_t *conf) |
35 | { | |
36 | int i, disks = conf->raid_disks; | |
37 | ||
38 | /* | |
39 | * Later we do read balancing on the read side | |
40 | * now we use the first available disk. | |
41 | */ | |
42 | ||
43 | rcu_read_lock(); | |
44 | for (i = 0; i < disks; i++) { | |
d6065f7b | 45 | mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev); |
b2d444d7 | 46 | if (rdev && test_bit(In_sync, &rdev->flags)) { |
1da177e4 LT |
47 | atomic_inc(&rdev->nr_pending); |
48 | rcu_read_unlock(); | |
49 | return i; | |
50 | } | |
51 | } | |
52 | rcu_read_unlock(); | |
53 | ||
54 | printk(KERN_ERR "multipath_map(): no more operational IO paths?\n"); | |
55 | return (-1); | |
56 | } | |
57 | ||
58 | static void multipath_reschedule_retry (struct multipath_bh *mp_bh) | |
59 | { | |
60 | unsigned long flags; | |
61 | mddev_t *mddev = mp_bh->mddev; | |
070ec55d | 62 | multipath_conf_t *conf = mddev->private; |
1da177e4 LT |
63 | |
64 | spin_lock_irqsave(&conf->device_lock, flags); | |
65 | list_add(&mp_bh->retry_list, &conf->retry_list); | |
66 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
67 | md_wakeup_thread(mddev->thread); | |
68 | } | |
69 | ||
70 | ||
71 | /* | |
72 | * multipath_end_bh_io() is called when we have finished servicing a multipathed | |
73 | * operation and are ready to return a success/failure code to the buffer | |
74 | * cache layer. | |
75 | */ | |
76 | static void multipath_end_bh_io (struct multipath_bh *mp_bh, int err) | |
77 | { | |
78 | struct bio *bio = mp_bh->master_bio; | |
070ec55d | 79 | multipath_conf_t *conf = mp_bh->mddev->private; |
1da177e4 | 80 | |
6712ecf8 | 81 | bio_endio(bio, err); |
1da177e4 LT |
82 | mempool_free(mp_bh, conf->pool); |
83 | } | |
84 | ||
6712ecf8 | 85 | static void multipath_end_request(struct bio *bio, int error) |
1da177e4 LT |
86 | { |
87 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
7b92813c | 88 | struct multipath_bh *mp_bh = bio->bi_private; |
070ec55d | 89 | multipath_conf_t *conf = mp_bh->mddev->private; |
1da177e4 LT |
90 | mdk_rdev_t *rdev = conf->multipaths[mp_bh->path].rdev; |
91 | ||
1da177e4 LT |
92 | if (uptodate) |
93 | multipath_end_bh_io(mp_bh, 0); | |
7b6d91da | 94 | else if (!(bio->bi_rw & REQ_RAHEAD)) { |
1da177e4 LT |
95 | /* |
96 | * oops, IO error: | |
97 | */ | |
98 | char b[BDEVNAME_SIZE]; | |
99 | md_error (mp_bh->mddev, rdev); | |
100 | printk(KERN_ERR "multipath: %s: rescheduling sector %llu\n", | |
101 | bdevname(rdev->bdev,b), | |
102 | (unsigned long long)bio->bi_sector); | |
103 | multipath_reschedule_retry(mp_bh); | |
104 | } else | |
105 | multipath_end_bh_io(mp_bh, error); | |
106 | rdev_dec_pending(rdev, conf->mddev); | |
1da177e4 LT |
107 | } |
108 | ||
109 | static void unplug_slaves(mddev_t *mddev) | |
110 | { | |
070ec55d | 111 | multipath_conf_t *conf = mddev->private; |
1da177e4 LT |
112 | int i; |
113 | ||
114 | rcu_read_lock(); | |
115 | for (i=0; i<mddev->raid_disks; i++) { | |
d6065f7b | 116 | mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev); |
b2d444d7 N |
117 | if (rdev && !test_bit(Faulty, &rdev->flags) |
118 | && atomic_read(&rdev->nr_pending)) { | |
165125e1 | 119 | struct request_queue *r_queue = bdev_get_queue(rdev->bdev); |
1da177e4 LT |
120 | |
121 | atomic_inc(&rdev->nr_pending); | |
122 | rcu_read_unlock(); | |
123 | ||
2ad8b1ef | 124 | blk_unplug(r_queue); |
1da177e4 LT |
125 | |
126 | rdev_dec_pending(rdev, mddev); | |
127 | rcu_read_lock(); | |
128 | } | |
129 | } | |
130 | rcu_read_unlock(); | |
131 | } | |
132 | ||
165125e1 | 133 | static void multipath_unplug(struct request_queue *q) |
1da177e4 LT |
134 | { |
135 | unplug_slaves(q->queuedata); | |
136 | } | |
137 | ||
138 | ||
21a52c6d | 139 | static int multipath_make_request(mddev_t *mddev, struct bio * bio) |
1da177e4 | 140 | { |
070ec55d | 141 | multipath_conf_t *conf = mddev->private; |
1da177e4 LT |
142 | struct multipath_bh * mp_bh; |
143 | struct multipath_info *multipath; | |
144 | ||
e9c7469b TH |
145 | if (unlikely(bio->bi_rw & REQ_FLUSH)) { |
146 | md_flush_request(mddev, bio); | |
e5dcdd80 N |
147 | return 0; |
148 | } | |
149 | ||
1da177e4 LT |
150 | mp_bh = mempool_alloc(conf->pool, GFP_NOIO); |
151 | ||
152 | mp_bh->master_bio = bio; | |
153 | mp_bh->mddev = mddev; | |
154 | ||
1da177e4 LT |
155 | mp_bh->path = multipath_map(conf); |
156 | if (mp_bh->path < 0) { | |
6712ecf8 | 157 | bio_endio(bio, -EIO); |
1da177e4 LT |
158 | mempool_free(mp_bh, conf->pool); |
159 | return 0; | |
160 | } | |
161 | multipath = conf->multipaths + mp_bh->path; | |
162 | ||
163 | mp_bh->bio = *bio; | |
164 | mp_bh->bio.bi_sector += multipath->rdev->data_offset; | |
165 | mp_bh->bio.bi_bdev = multipath->rdev->bdev; | |
7b6d91da | 166 | mp_bh->bio.bi_rw |= REQ_FAILFAST_TRANSPORT; |
1da177e4 LT |
167 | mp_bh->bio.bi_end_io = multipath_end_request; |
168 | mp_bh->bio.bi_private = mp_bh; | |
169 | generic_make_request(&mp_bh->bio); | |
170 | return 0; | |
171 | } | |
172 | ||
173 | static void multipath_status (struct seq_file *seq, mddev_t *mddev) | |
174 | { | |
070ec55d | 175 | multipath_conf_t *conf = mddev->private; |
1da177e4 LT |
176 | int i; |
177 | ||
178 | seq_printf (seq, " [%d/%d] [", conf->raid_disks, | |
179 | conf->working_disks); | |
180 | for (i = 0; i < conf->raid_disks; i++) | |
181 | seq_printf (seq, "%s", | |
182 | conf->multipaths[i].rdev && | |
b2d444d7 | 183 | test_bit(In_sync, &conf->multipaths[i].rdev->flags) ? "U" : "_"); |
1da177e4 LT |
184 | seq_printf (seq, "]"); |
185 | } | |
186 | ||
0d129228 N |
187 | static int multipath_congested(void *data, int bits) |
188 | { | |
189 | mddev_t *mddev = data; | |
070ec55d | 190 | multipath_conf_t *conf = mddev->private; |
0d129228 N |
191 | int i, ret = 0; |
192 | ||
3fa841d7 N |
193 | if (mddev_congested(mddev, bits)) |
194 | return 1; | |
195 | ||
0d129228 N |
196 | rcu_read_lock(); |
197 | for (i = 0; i < mddev->raid_disks ; i++) { | |
198 | mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev); | |
199 | if (rdev && !test_bit(Faulty, &rdev->flags)) { | |
165125e1 | 200 | struct request_queue *q = bdev_get_queue(rdev->bdev); |
0d129228 N |
201 | |
202 | ret |= bdi_congested(&q->backing_dev_info, bits); | |
203 | /* Just like multipath_map, we just check the | |
204 | * first available device | |
205 | */ | |
206 | break; | |
207 | } | |
208 | } | |
209 | rcu_read_unlock(); | |
210 | return ret; | |
211 | } | |
1da177e4 LT |
212 | |
213 | /* | |
214 | * Careful, this can execute in IRQ contexts as well! | |
215 | */ | |
216 | static void multipath_error (mddev_t *mddev, mdk_rdev_t *rdev) | |
217 | { | |
070ec55d | 218 | multipath_conf_t *conf = mddev->private; |
1da177e4 LT |
219 | |
220 | if (conf->working_disks <= 1) { | |
221 | /* | |
222 | * Uh oh, we can do nothing if this is our last path, but | |
223 | * first check if this is a queued request for a device | |
224 | * which has just failed. | |
225 | */ | |
226 | printk(KERN_ALERT | |
227 | "multipath: only one IO path left and IO error.\n"); | |
228 | /* leave it active... it's all we have */ | |
229 | } else { | |
230 | /* | |
231 | * Mark disk as unusable | |
232 | */ | |
b2d444d7 | 233 | if (!test_bit(Faulty, &rdev->flags)) { |
1da177e4 | 234 | char b[BDEVNAME_SIZE]; |
b2d444d7 N |
235 | clear_bit(In_sync, &rdev->flags); |
236 | set_bit(Faulty, &rdev->flags); | |
850b2b42 | 237 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
1da177e4 | 238 | conf->working_disks--; |
750a8f3e | 239 | mddev->degraded++; |
1da177e4 | 240 | printk(KERN_ALERT "multipath: IO failure on %s," |
d7a420c9 NA |
241 | " disabling IO path.\n" |
242 | "multipath: Operation continuing" | |
1da177e4 LT |
243 | " on %d IO paths.\n", |
244 | bdevname (rdev->bdev,b), | |
245 | conf->working_disks); | |
246 | } | |
247 | } | |
248 | } | |
249 | ||
250 | static void print_multipath_conf (multipath_conf_t *conf) | |
251 | { | |
252 | int i; | |
253 | struct multipath_info *tmp; | |
254 | ||
255 | printk("MULTIPATH conf printout:\n"); | |
256 | if (!conf) { | |
257 | printk("(conf==NULL)\n"); | |
258 | return; | |
259 | } | |
260 | printk(" --- wd:%d rd:%d\n", conf->working_disks, | |
261 | conf->raid_disks); | |
262 | ||
263 | for (i = 0; i < conf->raid_disks; i++) { | |
264 | char b[BDEVNAME_SIZE]; | |
265 | tmp = conf->multipaths + i; | |
266 | if (tmp->rdev) | |
267 | printk(" disk%d, o:%d, dev:%s\n", | |
b2d444d7 | 268 | i,!test_bit(Faulty, &tmp->rdev->flags), |
1da177e4 LT |
269 | bdevname(tmp->rdev->bdev,b)); |
270 | } | |
271 | } | |
272 | ||
273 | ||
274 | static int multipath_add_disk(mddev_t *mddev, mdk_rdev_t *rdev) | |
275 | { | |
276 | multipath_conf_t *conf = mddev->private; | |
352d768b | 277 | struct request_queue *q; |
199050ea | 278 | int err = -EEXIST; |
1da177e4 LT |
279 | int path; |
280 | struct multipath_info *p; | |
6c2fce2e NB |
281 | int first = 0; |
282 | int last = mddev->raid_disks - 1; | |
283 | ||
284 | if (rdev->raid_disk >= 0) | |
285 | first = last = rdev->raid_disk; | |
1da177e4 LT |
286 | |
287 | print_multipath_conf(conf); | |
288 | ||
6c2fce2e | 289 | for (path = first; path <= last; path++) |
1da177e4 | 290 | if ((p=conf->multipaths+path)->rdev == NULL) { |
352d768b | 291 | q = rdev->bdev->bd_disk->queue; |
8f6c2e4b MP |
292 | disk_stack_limits(mddev->gendisk, rdev->bdev, |
293 | rdev->data_offset << 9); | |
1da177e4 LT |
294 | |
295 | /* as we don't honour merge_bvec_fn, we must never risk | |
627a2d3c N |
296 | * violating it, so limit ->max_segments to one, lying |
297 | * within a single page. | |
1da177e4 LT |
298 | * (Note: it is very unlikely that a device with |
299 | * merge_bvec_fn will be involved in multipath.) | |
300 | */ | |
627a2d3c N |
301 | if (q->merge_bvec_fn) { |
302 | blk_queue_max_segments(mddev->queue, 1); | |
303 | blk_queue_segment_boundary(mddev->queue, | |
304 | PAGE_CACHE_SIZE - 1); | |
305 | } | |
1da177e4 LT |
306 | |
307 | conf->working_disks++; | |
750a8f3e | 308 | mddev->degraded--; |
1da177e4 | 309 | rdev->raid_disk = path; |
b2d444d7 | 310 | set_bit(In_sync, &rdev->flags); |
d6065f7b | 311 | rcu_assign_pointer(p->rdev, rdev); |
199050ea | 312 | err = 0; |
ac5e7113 | 313 | md_integrity_add_rdev(rdev, mddev); |
199050ea | 314 | break; |
1da177e4 LT |
315 | } |
316 | ||
317 | print_multipath_conf(conf); | |
199050ea NB |
318 | |
319 | return err; | |
1da177e4 LT |
320 | } |
321 | ||
322 | static int multipath_remove_disk(mddev_t *mddev, int number) | |
323 | { | |
324 | multipath_conf_t *conf = mddev->private; | |
325 | int err = 0; | |
326 | mdk_rdev_t *rdev; | |
327 | struct multipath_info *p = conf->multipaths + number; | |
328 | ||
329 | print_multipath_conf(conf); | |
330 | ||
331 | rdev = p->rdev; | |
332 | if (rdev) { | |
b2d444d7 | 333 | if (test_bit(In_sync, &rdev->flags) || |
1da177e4 | 334 | atomic_read(&rdev->nr_pending)) { |
dfc70645 N |
335 | printk(KERN_ERR "hot-remove-disk, slot %d is identified" |
336 | " but is still operational!\n", number); | |
1da177e4 LT |
337 | err = -EBUSY; |
338 | goto abort; | |
339 | } | |
340 | p->rdev = NULL; | |
fbd568a3 | 341 | synchronize_rcu(); |
1da177e4 LT |
342 | if (atomic_read(&rdev->nr_pending)) { |
343 | /* lost the race, try later */ | |
344 | err = -EBUSY; | |
345 | p->rdev = rdev; | |
ac5e7113 | 346 | goto abort; |
1da177e4 | 347 | } |
ac5e7113 | 348 | md_integrity_register(mddev); |
1da177e4 LT |
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; | |
070ec55d | 371 | multipath_conf_t *conf = mddev->private; |
1da177e4 LT |
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; | |
7b6d91da | 401 | bio->bi_rw |= REQ_FAILFAST_TRANSPORT; |
1da177e4 LT |
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 | ||
80c3a6ce DW |
410 | static sector_t multipath_size(mddev_t *mddev, sector_t sectors, int raid_disks) |
411 | { | |
412 | WARN_ONCE(sectors || raid_disks, | |
413 | "%s does not support generic reshape\n", __func__); | |
414 | ||
415 | return mddev->dev_sectors; | |
416 | } | |
417 | ||
1da177e4 LT |
418 | static int multipath_run (mddev_t *mddev) |
419 | { | |
420 | multipath_conf_t *conf; | |
421 | int disk_idx; | |
422 | struct multipath_info *disk; | |
423 | mdk_rdev_t *rdev; | |
1da177e4 | 424 | |
0894cc30 AN |
425 | if (md_check_no_bitmap(mddev)) |
426 | return -EINVAL; | |
427 | ||
1da177e4 LT |
428 | if (mddev->level != LEVEL_MULTIPATH) { |
429 | printk("multipath: %s: raid level not set to multipath IO (%d)\n", | |
430 | mdname(mddev), mddev->level); | |
431 | goto out; | |
432 | } | |
433 | /* | |
434 | * copy the already verified devices into our private MULTIPATH | |
435 | * bookkeeping area. [whatever we allocate in multipath_run(), | |
436 | * should be freed in multipath_stop()] | |
437 | */ | |
e7e72bf6 | 438 | mddev->queue->queue_lock = &mddev->queue->__queue_lock; |
1da177e4 | 439 | |
9ffae0cf | 440 | conf = kzalloc(sizeof(multipath_conf_t), GFP_KERNEL); |
1da177e4 LT |
441 | mddev->private = conf; |
442 | if (!conf) { | |
443 | printk(KERN_ERR | |
444 | "multipath: couldn't allocate memory for %s\n", | |
445 | mdname(mddev)); | |
446 | goto out; | |
447 | } | |
1da177e4 | 448 | |
9ffae0cf | 449 | conf->multipaths = kzalloc(sizeof(struct multipath_info)*mddev->raid_disks, |
1da177e4 LT |
450 | GFP_KERNEL); |
451 | if (!conf->multipaths) { | |
452 | printk(KERN_ERR | |
453 | "multipath: couldn't allocate memory for %s\n", | |
454 | mdname(mddev)); | |
455 | goto out_free_conf; | |
456 | } | |
1da177e4 | 457 | |
1da177e4 | 458 | conf->working_disks = 0; |
159ec1fc | 459 | list_for_each_entry(rdev, &mddev->disks, same_set) { |
1da177e4 LT |
460 | disk_idx = rdev->raid_disk; |
461 | if (disk_idx < 0 || | |
462 | disk_idx >= mddev->raid_disks) | |
463 | continue; | |
464 | ||
465 | disk = conf->multipaths + disk_idx; | |
466 | disk->rdev = rdev; | |
8f6c2e4b MP |
467 | disk_stack_limits(mddev->gendisk, rdev->bdev, |
468 | rdev->data_offset << 9); | |
1da177e4 | 469 | |
1da177e4 LT |
470 | /* as we don't honour merge_bvec_fn, we must never risk |
471 | * violating it, not that we ever expect a device with | |
472 | * a merge_bvec_fn to be involved in multipath */ | |
627a2d3c N |
473 | if (rdev->bdev->bd_disk->queue->merge_bvec_fn) { |
474 | blk_queue_max_segments(mddev->queue, 1); | |
475 | blk_queue_segment_boundary(mddev->queue, | |
476 | PAGE_CACHE_SIZE - 1); | |
477 | } | |
1da177e4 | 478 | |
b2d444d7 | 479 | if (!test_bit(Faulty, &rdev->flags)) |
1da177e4 LT |
480 | conf->working_disks++; |
481 | } | |
482 | ||
483 | conf->raid_disks = mddev->raid_disks; | |
1da177e4 LT |
484 | conf->mddev = mddev; |
485 | spin_lock_init(&conf->device_lock); | |
486 | INIT_LIST_HEAD(&conf->retry_list); | |
487 | ||
488 | if (!conf->working_disks) { | |
489 | printk(KERN_ERR "multipath: no operational IO paths for %s\n", | |
490 | mdname(mddev)); | |
491 | goto out_free_conf; | |
492 | } | |
2e333e89 | 493 | mddev->degraded = conf->raid_disks - conf->working_disks; |
1da177e4 | 494 | |
bbba809e | 495 | conf->pool = mempool_create_kmalloc_pool(NR_RESERVED_BUFS, |
26b6e051 | 496 | sizeof(struct multipath_bh)); |
1da177e4 LT |
497 | if (conf->pool == NULL) { |
498 | printk(KERN_ERR | |
499 | "multipath: couldn't allocate memory for %s\n", | |
500 | mdname(mddev)); | |
501 | goto out_free_conf; | |
502 | } | |
503 | ||
504 | { | |
0da3c619 | 505 | mddev->thread = md_register_thread(multipathd, mddev, NULL); |
1da177e4 LT |
506 | if (!mddev->thread) { |
507 | printk(KERN_ERR "multipath: couldn't allocate thread" | |
508 | " for %s\n", mdname(mddev)); | |
509 | goto out_free_conf; | |
510 | } | |
511 | } | |
512 | ||
513 | printk(KERN_INFO | |
514 | "multipath: array %s active with %d out of %d IO paths\n", | |
515 | mdname(mddev), conf->working_disks, mddev->raid_disks); | |
516 | /* | |
517 | * Ok, everything is just fine now | |
518 | */ | |
1f403624 | 519 | md_set_array_sectors(mddev, multipath_size(mddev, 0, 0)); |
7a5febe9 N |
520 | |
521 | mddev->queue->unplug_fn = multipath_unplug; | |
0d129228 N |
522 | mddev->queue->backing_dev_info.congested_fn = multipath_congested; |
523 | mddev->queue->backing_dev_info.congested_data = mddev; | |
ac5e7113 | 524 | md_integrity_register(mddev); |
1da177e4 LT |
525 | return 0; |
526 | ||
527 | out_free_conf: | |
528 | if (conf->pool) | |
529 | mempool_destroy(conf->pool); | |
990a8baf | 530 | kfree(conf->multipaths); |
1da177e4 LT |
531 | kfree(conf); |
532 | mddev->private = NULL; | |
533 | out: | |
534 | return -EIO; | |
535 | } | |
536 | ||
537 | ||
538 | static int multipath_stop (mddev_t *mddev) | |
539 | { | |
070ec55d | 540 | multipath_conf_t *conf = mddev->private; |
1da177e4 LT |
541 | |
542 | md_unregister_thread(mddev->thread); | |
543 | mddev->thread = NULL; | |
544 | blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ | |
545 | mempool_destroy(conf->pool); | |
546 | kfree(conf->multipaths); | |
547 | kfree(conf); | |
548 | mddev->private = NULL; | |
549 | return 0; | |
550 | } | |
551 | ||
2604b703 | 552 | static struct mdk_personality multipath_personality = |
1da177e4 LT |
553 | { |
554 | .name = "multipath", | |
2604b703 | 555 | .level = LEVEL_MULTIPATH, |
1da177e4 LT |
556 | .owner = THIS_MODULE, |
557 | .make_request = multipath_make_request, | |
558 | .run = multipath_run, | |
559 | .stop = multipath_stop, | |
560 | .status = multipath_status, | |
561 | .error_handler = multipath_error, | |
562 | .hot_add_disk = multipath_add_disk, | |
563 | .hot_remove_disk= multipath_remove_disk, | |
80c3a6ce | 564 | .size = multipath_size, |
1da177e4 LT |
565 | }; |
566 | ||
567 | static int __init multipath_init (void) | |
568 | { | |
2604b703 | 569 | return register_md_personality (&multipath_personality); |
1da177e4 LT |
570 | } |
571 | ||
572 | static void __exit multipath_exit (void) | |
573 | { | |
2604b703 | 574 | unregister_md_personality (&multipath_personality); |
1da177e4 LT |
575 | } |
576 | ||
577 | module_init(multipath_init); | |
578 | module_exit(multipath_exit); | |
579 | MODULE_LICENSE("GPL"); | |
0efb9e61 | 580 | MODULE_DESCRIPTION("simple multi-path personality for MD"); |
1da177e4 | 581 | MODULE_ALIAS("md-personality-7"); /* MULTIPATH */ |
d9d166c2 | 582 | MODULE_ALIAS("md-multipath"); |
2604b703 | 583 | MODULE_ALIAS("md-level--4"); |