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> |
43b2e5d8 | 25 | #include "md.h" |
ef740c37 | 26 | #include "multipath.h" |
1da177e4 LT |
27 | |
28 | #define MAX_WORK_PER_DISK 128 | |
29 | ||
30 | #define NR_RESERVED_BUFS 32 | |
31 | ||
32 | ||
1da177e4 LT |
33 | static int multipath_map (multipath_conf_t *conf) |
34 | { | |
35 | int i, disks = conf->raid_disks; | |
36 | ||
37 | /* | |
38 | * Later we do read balancing on the read side | |
39 | * now we use the first available disk. | |
40 | */ | |
41 | ||
42 | rcu_read_lock(); | |
43 | for (i = 0; i < disks; i++) { | |
d6065f7b | 44 | mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev); |
b2d444d7 | 45 | if (rdev && test_bit(In_sync, &rdev->flags)) { |
1da177e4 LT |
46 | atomic_inc(&rdev->nr_pending); |
47 | rcu_read_unlock(); | |
48 | return i; | |
49 | } | |
50 | } | |
51 | rcu_read_unlock(); | |
52 | ||
53 | printk(KERN_ERR "multipath_map(): no more operational IO paths?\n"); | |
54 | return (-1); | |
55 | } | |
56 | ||
57 | static void multipath_reschedule_retry (struct multipath_bh *mp_bh) | |
58 | { | |
59 | unsigned long flags; | |
60 | mddev_t *mddev = mp_bh->mddev; | |
070ec55d | 61 | multipath_conf_t *conf = mddev->private; |
1da177e4 LT |
62 | |
63 | spin_lock_irqsave(&conf->device_lock, flags); | |
64 | list_add(&mp_bh->retry_list, &conf->retry_list); | |
65 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
66 | md_wakeup_thread(mddev->thread); | |
67 | } | |
68 | ||
69 | ||
70 | /* | |
71 | * multipath_end_bh_io() is called when we have finished servicing a multipathed | |
72 | * operation and are ready to return a success/failure code to the buffer | |
73 | * cache layer. | |
74 | */ | |
75 | static void multipath_end_bh_io (struct multipath_bh *mp_bh, int err) | |
76 | { | |
77 | struct bio *bio = mp_bh->master_bio; | |
070ec55d | 78 | multipath_conf_t *conf = mp_bh->mddev->private; |
1da177e4 | 79 | |
6712ecf8 | 80 | bio_endio(bio, err); |
1da177e4 LT |
81 | mempool_free(mp_bh, conf->pool); |
82 | } | |
83 | ||
6712ecf8 | 84 | static void multipath_end_request(struct bio *bio, int error) |
1da177e4 LT |
85 | { |
86 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
87 | struct multipath_bh * mp_bh = (struct multipath_bh *)(bio->bi_private); | |
070ec55d | 88 | multipath_conf_t *conf = mp_bh->mddev->private; |
1da177e4 LT |
89 | mdk_rdev_t *rdev = conf->multipaths[mp_bh->path].rdev; |
90 | ||
1da177e4 LT |
91 | if (uptodate) |
92 | multipath_end_bh_io(mp_bh, 0); | |
1f98a13f | 93 | else if (!bio_rw_flagged(bio, BIO_RW_AHEAD)) { |
1da177e4 LT |
94 | /* |
95 | * oops, IO error: | |
96 | */ | |
97 | char b[BDEVNAME_SIZE]; | |
98 | md_error (mp_bh->mddev, rdev); | |
99 | printk(KERN_ERR "multipath: %s: rescheduling sector %llu\n", | |
100 | bdevname(rdev->bdev,b), | |
101 | (unsigned long long)bio->bi_sector); | |
102 | multipath_reschedule_retry(mp_bh); | |
103 | } else | |
104 | multipath_end_bh_io(mp_bh, error); | |
105 | rdev_dec_pending(rdev, conf->mddev); | |
1da177e4 LT |
106 | } |
107 | ||
108 | static void unplug_slaves(mddev_t *mddev) | |
109 | { | |
070ec55d | 110 | multipath_conf_t *conf = mddev->private; |
1da177e4 LT |
111 | int i; |
112 | ||
113 | rcu_read_lock(); | |
114 | for (i=0; i<mddev->raid_disks; i++) { | |
d6065f7b | 115 | mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev); |
b2d444d7 N |
116 | if (rdev && !test_bit(Faulty, &rdev->flags) |
117 | && atomic_read(&rdev->nr_pending)) { | |
165125e1 | 118 | struct request_queue *r_queue = bdev_get_queue(rdev->bdev); |
1da177e4 LT |
119 | |
120 | atomic_inc(&rdev->nr_pending); | |
121 | rcu_read_unlock(); | |
122 | ||
2ad8b1ef | 123 | blk_unplug(r_queue); |
1da177e4 LT |
124 | |
125 | rdev_dec_pending(rdev, mddev); | |
126 | rcu_read_lock(); | |
127 | } | |
128 | } | |
129 | rcu_read_unlock(); | |
130 | } | |
131 | ||
165125e1 | 132 | static void multipath_unplug(struct request_queue *q) |
1da177e4 LT |
133 | { |
134 | unplug_slaves(q->queuedata); | |
135 | } | |
136 | ||
137 | ||
165125e1 | 138 | static int multipath_make_request (struct request_queue *q, struct bio * bio) |
1da177e4 LT |
139 | { |
140 | mddev_t *mddev = q->queuedata; | |
070ec55d | 141 | multipath_conf_t *conf = mddev->private; |
1da177e4 LT |
142 | struct multipath_bh * mp_bh; |
143 | struct multipath_info *multipath; | |
a362357b | 144 | const int rw = bio_data_dir(bio); |
c9959059 | 145 | int cpu; |
1da177e4 | 146 | |
1f98a13f | 147 | if (unlikely(bio_rw_flagged(bio, BIO_RW_BARRIER))) { |
6712ecf8 | 148 | bio_endio(bio, -EOPNOTSUPP); |
e5dcdd80 N |
149 | return 0; |
150 | } | |
151 | ||
1da177e4 LT |
152 | mp_bh = mempool_alloc(conf->pool, GFP_NOIO); |
153 | ||
154 | mp_bh->master_bio = bio; | |
155 | mp_bh->mddev = mddev; | |
156 | ||
074a7aca TH |
157 | cpu = part_stat_lock(); |
158 | part_stat_inc(cpu, &mddev->gendisk->part0, ios[rw]); | |
159 | part_stat_add(cpu, &mddev->gendisk->part0, sectors[rw], | |
160 | bio_sectors(bio)); | |
161 | part_stat_unlock(); | |
1da177e4 LT |
162 | |
163 | mp_bh->path = multipath_map(conf); | |
164 | if (mp_bh->path < 0) { | |
6712ecf8 | 165 | bio_endio(bio, -EIO); |
1da177e4 LT |
166 | mempool_free(mp_bh, conf->pool); |
167 | return 0; | |
168 | } | |
169 | multipath = conf->multipaths + mp_bh->path; | |
170 | ||
171 | mp_bh->bio = *bio; | |
172 | mp_bh->bio.bi_sector += multipath->rdev->data_offset; | |
173 | mp_bh->bio.bi_bdev = multipath->rdev->bdev; | |
6000a368 | 174 | mp_bh->bio.bi_rw |= (1 << BIO_RW_FAILFAST_TRANSPORT); |
1da177e4 LT |
175 | mp_bh->bio.bi_end_io = multipath_end_request; |
176 | mp_bh->bio.bi_private = mp_bh; | |
177 | generic_make_request(&mp_bh->bio); | |
178 | return 0; | |
179 | } | |
180 | ||
181 | static void multipath_status (struct seq_file *seq, mddev_t *mddev) | |
182 | { | |
070ec55d | 183 | multipath_conf_t *conf = mddev->private; |
1da177e4 LT |
184 | int i; |
185 | ||
186 | seq_printf (seq, " [%d/%d] [", conf->raid_disks, | |
187 | conf->working_disks); | |
188 | for (i = 0; i < conf->raid_disks; i++) | |
189 | seq_printf (seq, "%s", | |
190 | conf->multipaths[i].rdev && | |
b2d444d7 | 191 | test_bit(In_sync, &conf->multipaths[i].rdev->flags) ? "U" : "_"); |
1da177e4 LT |
192 | seq_printf (seq, "]"); |
193 | } | |
194 | ||
0d129228 N |
195 | static int multipath_congested(void *data, int bits) |
196 | { | |
197 | mddev_t *mddev = data; | |
070ec55d | 198 | multipath_conf_t *conf = mddev->private; |
0d129228 N |
199 | int i, ret = 0; |
200 | ||
3fa841d7 N |
201 | if (mddev_congested(mddev, bits)) |
202 | return 1; | |
203 | ||
0d129228 N |
204 | rcu_read_lock(); |
205 | for (i = 0; i < mddev->raid_disks ; i++) { | |
206 | mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev); | |
207 | if (rdev && !test_bit(Faulty, &rdev->flags)) { | |
165125e1 | 208 | struct request_queue *q = bdev_get_queue(rdev->bdev); |
0d129228 N |
209 | |
210 | ret |= bdi_congested(&q->backing_dev_info, bits); | |
211 | /* Just like multipath_map, we just check the | |
212 | * first available device | |
213 | */ | |
214 | break; | |
215 | } | |
216 | } | |
217 | rcu_read_unlock(); | |
218 | return ret; | |
219 | } | |
1da177e4 LT |
220 | |
221 | /* | |
222 | * Careful, this can execute in IRQ contexts as well! | |
223 | */ | |
224 | static void multipath_error (mddev_t *mddev, mdk_rdev_t *rdev) | |
225 | { | |
070ec55d | 226 | multipath_conf_t *conf = mddev->private; |
1da177e4 LT |
227 | |
228 | if (conf->working_disks <= 1) { | |
229 | /* | |
230 | * Uh oh, we can do nothing if this is our last path, but | |
231 | * first check if this is a queued request for a device | |
232 | * which has just failed. | |
233 | */ | |
234 | printk(KERN_ALERT | |
235 | "multipath: only one IO path left and IO error.\n"); | |
236 | /* leave it active... it's all we have */ | |
237 | } else { | |
238 | /* | |
239 | * Mark disk as unusable | |
240 | */ | |
b2d444d7 | 241 | if (!test_bit(Faulty, &rdev->flags)) { |
1da177e4 | 242 | char b[BDEVNAME_SIZE]; |
b2d444d7 N |
243 | clear_bit(In_sync, &rdev->flags); |
244 | set_bit(Faulty, &rdev->flags); | |
850b2b42 | 245 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
1da177e4 | 246 | conf->working_disks--; |
750a8f3e | 247 | mddev->degraded++; |
1da177e4 | 248 | printk(KERN_ALERT "multipath: IO failure on %s," |
d7a420c9 NA |
249 | " disabling IO path.\n" |
250 | "multipath: Operation continuing" | |
1da177e4 LT |
251 | " on %d IO paths.\n", |
252 | bdevname (rdev->bdev,b), | |
253 | conf->working_disks); | |
254 | } | |
255 | } | |
256 | } | |
257 | ||
258 | static void print_multipath_conf (multipath_conf_t *conf) | |
259 | { | |
260 | int i; | |
261 | struct multipath_info *tmp; | |
262 | ||
263 | printk("MULTIPATH conf printout:\n"); | |
264 | if (!conf) { | |
265 | printk("(conf==NULL)\n"); | |
266 | return; | |
267 | } | |
268 | printk(" --- wd:%d rd:%d\n", conf->working_disks, | |
269 | conf->raid_disks); | |
270 | ||
271 | for (i = 0; i < conf->raid_disks; i++) { | |
272 | char b[BDEVNAME_SIZE]; | |
273 | tmp = conf->multipaths + i; | |
274 | if (tmp->rdev) | |
275 | printk(" disk%d, o:%d, dev:%s\n", | |
b2d444d7 | 276 | i,!test_bit(Faulty, &tmp->rdev->flags), |
1da177e4 LT |
277 | bdevname(tmp->rdev->bdev,b)); |
278 | } | |
279 | } | |
280 | ||
281 | ||
282 | static int multipath_add_disk(mddev_t *mddev, mdk_rdev_t *rdev) | |
283 | { | |
284 | multipath_conf_t *conf = mddev->private; | |
352d768b | 285 | struct request_queue *q; |
199050ea | 286 | int err = -EEXIST; |
1da177e4 LT |
287 | int path; |
288 | struct multipath_info *p; | |
6c2fce2e NB |
289 | int first = 0; |
290 | int last = mddev->raid_disks - 1; | |
291 | ||
292 | if (rdev->raid_disk >= 0) | |
293 | first = last = rdev->raid_disk; | |
1da177e4 LT |
294 | |
295 | print_multipath_conf(conf); | |
296 | ||
6c2fce2e | 297 | for (path = first; path <= last; path++) |
1da177e4 | 298 | if ((p=conf->multipaths+path)->rdev == NULL) { |
352d768b | 299 | q = rdev->bdev->bd_disk->queue; |
8f6c2e4b MP |
300 | disk_stack_limits(mddev->gendisk, rdev->bdev, |
301 | rdev->data_offset << 9); | |
1da177e4 LT |
302 | |
303 | /* as we don't honour merge_bvec_fn, we must never risk | |
304 | * violating it, so limit ->max_sector to one PAGE, as | |
305 | * a one page request is never in violation. | |
306 | * (Note: it is very unlikely that a device with | |
307 | * merge_bvec_fn will be involved in multipath.) | |
308 | */ | |
352d768b | 309 | if (q->merge_bvec_fn && |
ae03bf63 | 310 | queue_max_sectors(q) > (PAGE_SIZE>>9)) |
1da177e4 LT |
311 | blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9); |
312 | ||
313 | conf->working_disks++; | |
750a8f3e | 314 | mddev->degraded--; |
1da177e4 | 315 | rdev->raid_disk = path; |
b2d444d7 | 316 | set_bit(In_sync, &rdev->flags); |
d6065f7b | 317 | rcu_assign_pointer(p->rdev, rdev); |
199050ea | 318 | err = 0; |
ac5e7113 | 319 | md_integrity_add_rdev(rdev, mddev); |
199050ea | 320 | break; |
1da177e4 LT |
321 | } |
322 | ||
323 | print_multipath_conf(conf); | |
199050ea NB |
324 | |
325 | return err; | |
1da177e4 LT |
326 | } |
327 | ||
328 | static int multipath_remove_disk(mddev_t *mddev, int number) | |
329 | { | |
330 | multipath_conf_t *conf = mddev->private; | |
331 | int err = 0; | |
332 | mdk_rdev_t *rdev; | |
333 | struct multipath_info *p = conf->multipaths + number; | |
334 | ||
335 | print_multipath_conf(conf); | |
336 | ||
337 | rdev = p->rdev; | |
338 | if (rdev) { | |
b2d444d7 | 339 | if (test_bit(In_sync, &rdev->flags) || |
1da177e4 | 340 | atomic_read(&rdev->nr_pending)) { |
dfc70645 N |
341 | printk(KERN_ERR "hot-remove-disk, slot %d is identified" |
342 | " but is still operational!\n", number); | |
1da177e4 LT |
343 | err = -EBUSY; |
344 | goto abort; | |
345 | } | |
346 | p->rdev = NULL; | |
fbd568a3 | 347 | synchronize_rcu(); |
1da177e4 LT |
348 | if (atomic_read(&rdev->nr_pending)) { |
349 | /* lost the race, try later */ | |
350 | err = -EBUSY; | |
351 | p->rdev = rdev; | |
ac5e7113 | 352 | goto abort; |
1da177e4 | 353 | } |
ac5e7113 | 354 | md_integrity_register(mddev); |
1da177e4 LT |
355 | } |
356 | abort: | |
357 | ||
358 | print_multipath_conf(conf); | |
359 | return err; | |
360 | } | |
361 | ||
362 | ||
363 | ||
364 | /* | |
365 | * This is a kernel thread which: | |
366 | * | |
367 | * 1. Retries failed read operations on working multipaths. | |
368 | * 2. Updates the raid superblock when problems encounter. | |
369 | * 3. Performs writes following reads for array syncronising. | |
370 | */ | |
371 | ||
372 | static void multipathd (mddev_t *mddev) | |
373 | { | |
374 | struct multipath_bh *mp_bh; | |
375 | struct bio *bio; | |
376 | unsigned long flags; | |
070ec55d | 377 | multipath_conf_t *conf = mddev->private; |
1da177e4 LT |
378 | struct list_head *head = &conf->retry_list; |
379 | ||
380 | md_check_recovery(mddev); | |
381 | for (;;) { | |
382 | char b[BDEVNAME_SIZE]; | |
383 | spin_lock_irqsave(&conf->device_lock, flags); | |
384 | if (list_empty(head)) | |
385 | break; | |
386 | mp_bh = list_entry(head->prev, struct multipath_bh, retry_list); | |
387 | list_del(head->prev); | |
388 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
389 | ||
390 | bio = &mp_bh->bio; | |
391 | bio->bi_sector = mp_bh->master_bio->bi_sector; | |
392 | ||
393 | if ((mp_bh->path = multipath_map (conf))<0) { | |
394 | printk(KERN_ALERT "multipath: %s: unrecoverable IO read" | |
395 | " error for block %llu\n", | |
396 | bdevname(bio->bi_bdev,b), | |
397 | (unsigned long long)bio->bi_sector); | |
398 | multipath_end_bh_io(mp_bh, -EIO); | |
399 | } else { | |
400 | printk(KERN_ERR "multipath: %s: redirecting sector %llu" | |
401 | " to another IO path\n", | |
402 | bdevname(bio->bi_bdev,b), | |
403 | (unsigned long long)bio->bi_sector); | |
404 | *bio = *(mp_bh->master_bio); | |
405 | bio->bi_sector += conf->multipaths[mp_bh->path].rdev->data_offset; | |
406 | bio->bi_bdev = conf->multipaths[mp_bh->path].rdev->bdev; | |
6000a368 | 407 | bio->bi_rw |= (1 << BIO_RW_FAILFAST_TRANSPORT); |
1da177e4 LT |
408 | bio->bi_end_io = multipath_end_request; |
409 | bio->bi_private = mp_bh; | |
410 | generic_make_request(bio); | |
411 | } | |
412 | } | |
413 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
414 | } | |
415 | ||
80c3a6ce DW |
416 | static sector_t multipath_size(mddev_t *mddev, sector_t sectors, int raid_disks) |
417 | { | |
418 | WARN_ONCE(sectors || raid_disks, | |
419 | "%s does not support generic reshape\n", __func__); | |
420 | ||
421 | return mddev->dev_sectors; | |
422 | } | |
423 | ||
1da177e4 LT |
424 | static int multipath_run (mddev_t *mddev) |
425 | { | |
426 | multipath_conf_t *conf; | |
427 | int disk_idx; | |
428 | struct multipath_info *disk; | |
429 | mdk_rdev_t *rdev; | |
1da177e4 | 430 | |
0894cc30 AN |
431 | if (md_check_no_bitmap(mddev)) |
432 | return -EINVAL; | |
433 | ||
1da177e4 LT |
434 | if (mddev->level != LEVEL_MULTIPATH) { |
435 | printk("multipath: %s: raid level not set to multipath IO (%d)\n", | |
436 | mdname(mddev), mddev->level); | |
437 | goto out; | |
438 | } | |
439 | /* | |
440 | * copy the already verified devices into our private MULTIPATH | |
441 | * bookkeeping area. [whatever we allocate in multipath_run(), | |
442 | * should be freed in multipath_stop()] | |
443 | */ | |
e7e72bf6 | 444 | mddev->queue->queue_lock = &mddev->queue->__queue_lock; |
1da177e4 | 445 | |
9ffae0cf | 446 | conf = kzalloc(sizeof(multipath_conf_t), GFP_KERNEL); |
1da177e4 LT |
447 | mddev->private = conf; |
448 | if (!conf) { | |
449 | printk(KERN_ERR | |
450 | "multipath: couldn't allocate memory for %s\n", | |
451 | mdname(mddev)); | |
452 | goto out; | |
453 | } | |
1da177e4 | 454 | |
9ffae0cf | 455 | conf->multipaths = kzalloc(sizeof(struct multipath_info)*mddev->raid_disks, |
1da177e4 LT |
456 | GFP_KERNEL); |
457 | if (!conf->multipaths) { | |
458 | printk(KERN_ERR | |
459 | "multipath: couldn't allocate memory for %s\n", | |
460 | mdname(mddev)); | |
461 | goto out_free_conf; | |
462 | } | |
1da177e4 | 463 | |
1da177e4 | 464 | conf->working_disks = 0; |
159ec1fc | 465 | list_for_each_entry(rdev, &mddev->disks, same_set) { |
1da177e4 LT |
466 | disk_idx = rdev->raid_disk; |
467 | if (disk_idx < 0 || | |
468 | disk_idx >= mddev->raid_disks) | |
469 | continue; | |
470 | ||
471 | disk = conf->multipaths + disk_idx; | |
472 | disk->rdev = rdev; | |
8f6c2e4b MP |
473 | disk_stack_limits(mddev->gendisk, rdev->bdev, |
474 | rdev->data_offset << 9); | |
1da177e4 | 475 | |
1da177e4 LT |
476 | /* as we don't honour merge_bvec_fn, we must never risk |
477 | * violating it, not that we ever expect a device with | |
478 | * a merge_bvec_fn to be involved in multipath */ | |
479 | if (rdev->bdev->bd_disk->queue->merge_bvec_fn && | |
ae03bf63 | 480 | queue_max_sectors(mddev->queue) > (PAGE_SIZE>>9)) |
1da177e4 LT |
481 | blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9); |
482 | ||
b2d444d7 | 483 | if (!test_bit(Faulty, &rdev->flags)) |
1da177e4 LT |
484 | conf->working_disks++; |
485 | } | |
486 | ||
487 | conf->raid_disks = mddev->raid_disks; | |
1da177e4 LT |
488 | conf->mddev = mddev; |
489 | spin_lock_init(&conf->device_lock); | |
490 | INIT_LIST_HEAD(&conf->retry_list); | |
491 | ||
492 | if (!conf->working_disks) { | |
493 | printk(KERN_ERR "multipath: no operational IO paths for %s\n", | |
494 | mdname(mddev)); | |
495 | goto out_free_conf; | |
496 | } | |
2e333e89 | 497 | mddev->degraded = conf->raid_disks - conf->working_disks; |
1da177e4 | 498 | |
bbba809e | 499 | conf->pool = mempool_create_kmalloc_pool(NR_RESERVED_BUFS, |
26b6e051 | 500 | sizeof(struct multipath_bh)); |
1da177e4 LT |
501 | if (conf->pool == NULL) { |
502 | printk(KERN_ERR | |
503 | "multipath: couldn't allocate memory for %s\n", | |
504 | mdname(mddev)); | |
505 | goto out_free_conf; | |
506 | } | |
507 | ||
508 | { | |
0da3c619 | 509 | mddev->thread = md_register_thread(multipathd, mddev, NULL); |
1da177e4 LT |
510 | if (!mddev->thread) { |
511 | printk(KERN_ERR "multipath: couldn't allocate thread" | |
512 | " for %s\n", mdname(mddev)); | |
513 | goto out_free_conf; | |
514 | } | |
515 | } | |
516 | ||
517 | printk(KERN_INFO | |
518 | "multipath: array %s active with %d out of %d IO paths\n", | |
519 | mdname(mddev), conf->working_disks, mddev->raid_disks); | |
520 | /* | |
521 | * Ok, everything is just fine now | |
522 | */ | |
1f403624 | 523 | md_set_array_sectors(mddev, multipath_size(mddev, 0, 0)); |
7a5febe9 N |
524 | |
525 | mddev->queue->unplug_fn = multipath_unplug; | |
0d129228 N |
526 | mddev->queue->backing_dev_info.congested_fn = multipath_congested; |
527 | mddev->queue->backing_dev_info.congested_data = mddev; | |
ac5e7113 | 528 | md_integrity_register(mddev); |
1da177e4 LT |
529 | return 0; |
530 | ||
531 | out_free_conf: | |
532 | if (conf->pool) | |
533 | mempool_destroy(conf->pool); | |
990a8baf | 534 | kfree(conf->multipaths); |
1da177e4 LT |
535 | kfree(conf); |
536 | mddev->private = NULL; | |
537 | out: | |
538 | return -EIO; | |
539 | } | |
540 | ||
541 | ||
542 | static int multipath_stop (mddev_t *mddev) | |
543 | { | |
070ec55d | 544 | multipath_conf_t *conf = mddev->private; |
1da177e4 LT |
545 | |
546 | md_unregister_thread(mddev->thread); | |
547 | mddev->thread = NULL; | |
548 | blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ | |
549 | mempool_destroy(conf->pool); | |
550 | kfree(conf->multipaths); | |
551 | kfree(conf); | |
552 | mddev->private = NULL; | |
553 | return 0; | |
554 | } | |
555 | ||
2604b703 | 556 | static struct mdk_personality multipath_personality = |
1da177e4 LT |
557 | { |
558 | .name = "multipath", | |
2604b703 | 559 | .level = LEVEL_MULTIPATH, |
1da177e4 LT |
560 | .owner = THIS_MODULE, |
561 | .make_request = multipath_make_request, | |
562 | .run = multipath_run, | |
563 | .stop = multipath_stop, | |
564 | .status = multipath_status, | |
565 | .error_handler = multipath_error, | |
566 | .hot_add_disk = multipath_add_disk, | |
567 | .hot_remove_disk= multipath_remove_disk, | |
80c3a6ce | 568 | .size = multipath_size, |
1da177e4 LT |
569 | }; |
570 | ||
571 | static int __init multipath_init (void) | |
572 | { | |
2604b703 | 573 | return register_md_personality (&multipath_personality); |
1da177e4 LT |
574 | } |
575 | ||
576 | static void __exit multipath_exit (void) | |
577 | { | |
2604b703 | 578 | unregister_md_personality (&multipath_personality); |
1da177e4 LT |
579 | } |
580 | ||
581 | module_init(multipath_init); | |
582 | module_exit(multipath_exit); | |
583 | MODULE_LICENSE("GPL"); | |
584 | MODULE_ALIAS("md-personality-7"); /* MULTIPATH */ | |
d9d166c2 | 585 | MODULE_ALIAS("md-multipath"); |
2604b703 | 586 | MODULE_ALIAS("md-level--4"); |