Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
a1452a37 | 2 | * Interface to Linux block layer for MTD 'translation layers'. |
1da177e4 | 3 | * |
a1452a37 DW |
4 | * Copyright © 2003-2010 David Woodhouse <dwmw2@infradead.org> |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License as published by | |
8 | * the Free Software Foundation; either version 2 of the License, or | |
9 | * (at your option) any later version. | |
10 | * | |
11 | * This program is distributed in the hope that it will be useful, | |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | * GNU General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * along with this program; if not, write to the Free Software | |
18 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
1da177e4 LT |
19 | * |
20 | */ | |
21 | ||
22 | #include <linux/kernel.h> | |
23 | #include <linux/slab.h> | |
24 | #include <linux/module.h> | |
25 | #include <linux/list.h> | |
26 | #include <linux/fs.h> | |
27 | #include <linux/mtd/blktrans.h> | |
28 | #include <linux/mtd/mtd.h> | |
29 | #include <linux/blkdev.h> | |
30 | #include <linux/blkpg.h> | |
31 | #include <linux/spinlock.h> | |
32 | #include <linux/hdreg.h> | |
33 | #include <linux/init.h> | |
48b19268 | 34 | #include <linux/mutex.h> |
99f9b243 | 35 | #include <linux/kthread.h> |
1da177e4 | 36 | #include <asm/uaccess.h> |
1da177e4 | 37 | |
356d70f1 | 38 | #include "mtdcore.h" |
1da177e4 | 39 | |
356d70f1 | 40 | static LIST_HEAD(blktrans_majors); |
048d8719 ML |
41 | static DEFINE_MUTEX(blktrans_ref_mutex); |
42 | ||
43 | void blktrans_dev_release(struct kref *kref) | |
44 | { | |
45 | struct mtd_blktrans_dev *dev = | |
46 | container_of(kref, struct mtd_blktrans_dev, ref); | |
47 | ||
48 | dev->disk->private_data = NULL; | |
e4d64cab | 49 | blk_cleanup_queue(dev->rq); |
048d8719 ML |
50 | put_disk(dev->disk); |
51 | list_del(&dev->list); | |
52 | kfree(dev); | |
53 | } | |
54 | ||
55 | static struct mtd_blktrans_dev *blktrans_dev_get(struct gendisk *disk) | |
56 | { | |
57 | struct mtd_blktrans_dev *dev; | |
58 | ||
59 | mutex_lock(&blktrans_ref_mutex); | |
60 | dev = disk->private_data; | |
61 | ||
62 | if (!dev) | |
63 | goto unlock; | |
64 | kref_get(&dev->ref); | |
65 | unlock: | |
66 | mutex_unlock(&blktrans_ref_mutex); | |
67 | return dev; | |
68 | } | |
69 | ||
70 | void blktrans_dev_put(struct mtd_blktrans_dev *dev) | |
71 | { | |
72 | mutex_lock(&blktrans_ref_mutex); | |
73 | kref_put(&dev->ref, blktrans_dev_release); | |
74 | mutex_unlock(&blktrans_ref_mutex); | |
75 | } | |
1da177e4 | 76 | |
1da177e4 LT |
77 | |
78 | static int do_blktrans_request(struct mtd_blktrans_ops *tr, | |
79 | struct mtd_blktrans_dev *dev, | |
80 | struct request *req) | |
81 | { | |
82 | unsigned long block, nsect; | |
83 | char *buf; | |
84 | ||
83096ebf | 85 | block = blk_rq_pos(req) << 9 >> tr->blkshift; |
1011c1b9 | 86 | nsect = blk_rq_cur_bytes(req) >> tr->blkshift; |
19187672 | 87 | |
1da177e4 LT |
88 | buf = req->buffer; |
89 | ||
33659ebb | 90 | if (req->cmd_type != REQ_TYPE_FS) |
f06d9a2b | 91 | return -EIO; |
1da177e4 | 92 | |
83096ebf TH |
93 | if (blk_rq_pos(req) + blk_rq_cur_sectors(req) > |
94 | get_capacity(req->rq_disk)) | |
f06d9a2b | 95 | return -EIO; |
1da177e4 | 96 | |
33659ebb | 97 | if (req->cmd_flags & REQ_DISCARD) |
1122a26f CH |
98 | return tr->discard(dev, block, nsect); |
99 | ||
1da177e4 LT |
100 | switch(rq_data_dir(req)) { |
101 | case READ: | |
19187672 | 102 | for (; nsect > 0; nsect--, block++, buf += tr->blksize) |
1da177e4 | 103 | if (tr->readsect(dev, block, buf)) |
f06d9a2b | 104 | return -EIO; |
2d4dc890 | 105 | rq_flush_dcache_pages(req); |
f06d9a2b | 106 | return 0; |
1da177e4 LT |
107 | case WRITE: |
108 | if (!tr->writesect) | |
f06d9a2b | 109 | return -EIO; |
1da177e4 | 110 | |
2d4dc890 | 111 | rq_flush_dcache_pages(req); |
19187672 | 112 | for (; nsect > 0; nsect--, block++, buf += tr->blksize) |
1da177e4 | 113 | if (tr->writesect(dev, block, buf)) |
f06d9a2b TH |
114 | return -EIO; |
115 | return 0; | |
1da177e4 | 116 | default: |
9a292308 | 117 | printk(KERN_NOTICE "Unknown request %u\n", rq_data_dir(req)); |
f06d9a2b | 118 | return -EIO; |
1da177e4 LT |
119 | } |
120 | } | |
121 | ||
122 | static int mtd_blktrans_thread(void *arg) | |
123 | { | |
a8638622 ML |
124 | struct mtd_blktrans_dev *dev = arg; |
125 | struct request_queue *rq = dev->rq; | |
1498ada7 | 126 | struct request *req = NULL; |
1da177e4 | 127 | |
1da177e4 | 128 | spin_lock_irq(rq->queue_lock); |
1498ada7 | 129 | |
3e67fe45 | 130 | while (!kthread_should_stop()) { |
f06d9a2b | 131 | int res; |
1da177e4 | 132 | |
9934c8c0 | 133 | if (!req && !(req = blk_fetch_request(rq))) { |
1da177e4 | 134 | set_current_state(TASK_INTERRUPTIBLE); |
12aebf3e ML |
135 | |
136 | if (kthread_should_stop()) | |
137 | set_current_state(TASK_RUNNING); | |
138 | ||
1da177e4 | 139 | spin_unlock_irq(rq->queue_lock); |
1da177e4 | 140 | schedule(); |
1da177e4 | 141 | spin_lock_irq(rq->queue_lock); |
1da177e4 LT |
142 | continue; |
143 | } | |
144 | ||
1da177e4 LT |
145 | spin_unlock_irq(rq->queue_lock); |
146 | ||
48b19268 | 147 | mutex_lock(&dev->lock); |
a8638622 | 148 | res = do_blktrans_request(dev->tr, dev, req); |
48b19268 | 149 | mutex_unlock(&dev->lock); |
1da177e4 LT |
150 | |
151 | spin_lock_irq(rq->queue_lock); | |
152 | ||
1498ada7 TH |
153 | if (!__blk_end_request_cur(req, res)) |
154 | req = NULL; | |
1da177e4 | 155 | } |
1498ada7 TH |
156 | |
157 | if (req) | |
158 | __blk_end_request_all(req, -EIO); | |
159 | ||
1da177e4 LT |
160 | spin_unlock_irq(rq->queue_lock); |
161 | ||
3e67fe45 | 162 | return 0; |
1da177e4 LT |
163 | } |
164 | ||
165 | static void mtd_blktrans_request(struct request_queue *rq) | |
166 | { | |
048d8719 ML |
167 | struct mtd_blktrans_dev *dev; |
168 | struct request *req = NULL; | |
169 | ||
170 | dev = rq->queuedata; | |
1da177e4 | 171 | |
048d8719 ML |
172 | if (!dev) |
173 | while ((req = blk_fetch_request(rq)) != NULL) | |
174 | __blk_end_request_all(req, -ENODEV); | |
175 | else | |
176 | wake_up_process(dev->thread); | |
177 | } | |
1da177e4 | 178 | |
af0e2a0a | 179 | static int blktrans_open(struct block_device *bdev, fmode_t mode) |
1da177e4 | 180 | { |
048d8719 | 181 | struct mtd_blktrans_dev *dev = blktrans_dev_get(bdev->bd_disk); |
008c751e | 182 | int ret = 0; |
048d8719 ML |
183 | |
184 | if (!dev) | |
6e9624b8 | 185 | return -ERESTARTSYS; /* FIXME: busy loop! -arnd*/ |
048d8719 ML |
186 | |
187 | mutex_lock(&dev->lock); | |
188 | ||
008c751e | 189 | if (dev->open++) |
048d8719 | 190 | goto unlock; |
048d8719 | 191 | |
008c751e ML |
192 | kref_get(&dev->ref); |
193 | __module_get(dev->tr->owner); | |
194 | ||
195 | if (dev->mtd) { | |
196 | ret = dev->tr->open ? dev->tr->open(dev) : 0; | |
197 | __get_mtd_device(dev->mtd); | |
198 | } | |
048d8719 | 199 | |
048d8719 ML |
200 | unlock: |
201 | mutex_unlock(&dev->lock); | |
202 | blktrans_dev_put(dev); | |
1da177e4 LT |
203 | return ret; |
204 | } | |
205 | ||
af0e2a0a | 206 | static int blktrans_release(struct gendisk *disk, fmode_t mode) |
1da177e4 | 207 | { |
048d8719 | 208 | struct mtd_blktrans_dev *dev = blktrans_dev_get(disk); |
008c751e | 209 | int ret = 0; |
1da177e4 | 210 | |
048d8719 ML |
211 | if (!dev) |
212 | return ret; | |
1da177e4 | 213 | |
048d8719 ML |
214 | mutex_lock(&dev->lock); |
215 | ||
008c751e | 216 | if (--dev->open) |
048d8719 ML |
217 | goto unlock; |
218 | ||
008c751e ML |
219 | kref_put(&dev->ref, blktrans_dev_release); |
220 | module_put(dev->tr->owner); | |
221 | ||
222 | if (dev->mtd) { | |
223 | ret = dev->tr->release ? dev->tr->release(dev) : 0; | |
224 | __put_mtd_device(dev->mtd); | |
225 | } | |
048d8719 ML |
226 | unlock: |
227 | mutex_unlock(&dev->lock); | |
228 | blktrans_dev_put(dev); | |
1da177e4 LT |
229 | return ret; |
230 | } | |
231 | ||
a885c8c4 CH |
232 | static int blktrans_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
233 | { | |
048d8719 ML |
234 | struct mtd_blktrans_dev *dev = blktrans_dev_get(bdev->bd_disk); |
235 | int ret = -ENXIO; | |
236 | ||
237 | if (!dev) | |
238 | return ret; | |
239 | ||
240 | mutex_lock(&dev->lock); | |
a885c8c4 | 241 | |
048d8719 ML |
242 | if (!dev->mtd) |
243 | goto unlock; | |
244 | ||
245 | ret = dev->tr->getgeo ? dev->tr->getgeo(dev, geo) : 0; | |
246 | unlock: | |
247 | mutex_unlock(&dev->lock); | |
248 | blktrans_dev_put(dev); | |
249 | return ret; | |
a885c8c4 | 250 | } |
1da177e4 | 251 | |
af0e2a0a | 252 | static int blktrans_ioctl(struct block_device *bdev, fmode_t mode, |
1da177e4 LT |
253 | unsigned int cmd, unsigned long arg) |
254 | { | |
048d8719 ML |
255 | struct mtd_blktrans_dev *dev = blktrans_dev_get(bdev->bd_disk); |
256 | int ret = -ENXIO; | |
257 | ||
258 | if (!dev) | |
259 | return ret; | |
260 | ||
261 | mutex_lock(&dev->lock); | |
262 | ||
263 | if (!dev->mtd) | |
264 | goto unlock; | |
1da177e4 LT |
265 | |
266 | switch (cmd) { | |
267 | case BLKFLSBUF: | |
048d8719 | 268 | ret = dev->tr->flush ? dev->tr->flush(dev) : 0; |
007c2d87 | 269 | break; |
1da177e4 | 270 | default: |
048d8719 | 271 | ret = -ENOTTY; |
1da177e4 | 272 | } |
048d8719 ML |
273 | unlock: |
274 | mutex_unlock(&dev->lock); | |
275 | blktrans_dev_put(dev); | |
276 | return ret; | |
1da177e4 LT |
277 | } |
278 | ||
83d5cde4 | 279 | static const struct block_device_operations mtd_blktrans_ops = { |
1da177e4 | 280 | .owner = THIS_MODULE, |
af0e2a0a AV |
281 | .open = blktrans_open, |
282 | .release = blktrans_release, | |
8a6cfeb6 | 283 | .ioctl = blktrans_ioctl, |
a885c8c4 | 284 | .getgeo = blktrans_getgeo, |
1da177e4 LT |
285 | }; |
286 | ||
287 | int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new) | |
288 | { | |
289 | struct mtd_blktrans_ops *tr = new->tr; | |
71a928c0 | 290 | struct mtd_blktrans_dev *d; |
1da177e4 LT |
291 | int last_devnum = -1; |
292 | struct gendisk *gd; | |
a8638622 | 293 | int ret; |
1da177e4 | 294 | |
b3561ea9 | 295 | if (mutex_trylock(&mtd_table_mutex)) { |
48b19268 | 296 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
297 | BUG(); |
298 | } | |
299 | ||
048d8719 | 300 | mutex_lock(&blktrans_ref_mutex); |
71a928c0 | 301 | list_for_each_entry(d, &tr->devs, list) { |
1da177e4 LT |
302 | if (new->devnum == -1) { |
303 | /* Use first free number */ | |
304 | if (d->devnum != last_devnum+1) { | |
305 | /* Found a free devnum. Plug it in here */ | |
306 | new->devnum = last_devnum+1; | |
307 | list_add_tail(&new->list, &d->list); | |
308 | goto added; | |
309 | } | |
310 | } else if (d->devnum == new->devnum) { | |
311 | /* Required number taken */ | |
048d8719 | 312 | mutex_unlock(&blktrans_ref_mutex); |
1da177e4 LT |
313 | return -EBUSY; |
314 | } else if (d->devnum > new->devnum) { | |
315 | /* Required number was free */ | |
316 | list_add_tail(&new->list, &d->list); | |
317 | goto added; | |
97894cda | 318 | } |
1da177e4 LT |
319 | last_devnum = d->devnum; |
320 | } | |
a8638622 ML |
321 | |
322 | ret = -EBUSY; | |
1da177e4 LT |
323 | if (new->devnum == -1) |
324 | new->devnum = last_devnum+1; | |
325 | ||
4d3a8534 BH |
326 | /* Check that the device and any partitions will get valid |
327 | * minor numbers and that the disk naming code below can cope | |
328 | * with this number. */ | |
329 | if (new->devnum > (MINORMASK >> tr->part_bits) || | |
048d8719 ML |
330 | (tr->part_bits && new->devnum >= 27 * 26)) { |
331 | mutex_unlock(&blktrans_ref_mutex); | |
a8638622 | 332 | goto error1; |
048d8719 | 333 | } |
1da177e4 | 334 | |
1da177e4 LT |
335 | list_add_tail(&new->list, &tr->devs); |
336 | added: | |
048d8719 ML |
337 | mutex_unlock(&blktrans_ref_mutex); |
338 | ||
ce37ab42 | 339 | mutex_init(&new->lock); |
048d8719 | 340 | kref_init(&new->ref); |
1da177e4 LT |
341 | if (!tr->writesect) |
342 | new->readonly = 1; | |
343 | ||
a8638622 ML |
344 | /* Create gendisk */ |
345 | ret = -ENOMEM; | |
1da177e4 | 346 | gd = alloc_disk(1 << tr->part_bits); |
a8638622 ML |
347 | |
348 | if (!gd) | |
349 | goto error2; | |
350 | ||
351 | new->disk = gd; | |
352 | gd->private_data = new; | |
1da177e4 LT |
353 | gd->major = tr->major; |
354 | gd->first_minor = (new->devnum) << tr->part_bits; | |
355 | gd->fops = &mtd_blktrans_ops; | |
97894cda | 356 | |
65a8de36 TP |
357 | if (tr->part_bits) |
358 | if (new->devnum < 26) | |
359 | snprintf(gd->disk_name, sizeof(gd->disk_name), | |
360 | "%s%c", tr->name, 'a' + new->devnum); | |
361 | else | |
362 | snprintf(gd->disk_name, sizeof(gd->disk_name), | |
363 | "%s%c%c", tr->name, | |
364 | 'a' - 1 + new->devnum / 26, | |
365 | 'a' + new->devnum % 26); | |
366 | else | |
367 | snprintf(gd->disk_name, sizeof(gd->disk_name), | |
368 | "%s%d", tr->name, new->devnum); | |
1da177e4 | 369 | |
19187672 | 370 | set_capacity(gd, (new->size * tr->blksize) >> 9); |
1da177e4 | 371 | |
a8638622 ML |
372 | /* Create the request queue */ |
373 | spin_lock_init(&new->queue_lock); | |
374 | new->rq = blk_init_queue(mtd_blktrans_request, &new->queue_lock); | |
375 | ||
376 | if (!new->rq) | |
377 | goto error3; | |
378 | ||
379 | new->rq->queuedata = new; | |
380 | blk_queue_logical_block_size(new->rq, tr->blksize); | |
381 | ||
382 | if (tr->discard) | |
383 | queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, | |
384 | new->rq); | |
385 | ||
386 | gd->queue = new->rq; | |
387 | ||
388 | /* Create processing thread */ | |
389 | /* TODO: workqueue ? */ | |
390 | new->thread = kthread_run(mtd_blktrans_thread, new, | |
391 | "%s%d", tr->name, new->mtd->index); | |
392 | if (IS_ERR(new->thread)) { | |
393 | ret = PTR_ERR(new->thread); | |
394 | goto error4; | |
395 | } | |
d694846b | 396 | gd->driverfs_dev = &new->mtd->dev; |
1da177e4 LT |
397 | |
398 | if (new->readonly) | |
399 | set_disk_ro(gd, 1); | |
400 | ||
401 | add_disk(gd); | |
026ec578 | 402 | |
133fa8c7 ML |
403 | if (new->disk_attributes) { |
404 | ret = sysfs_create_group(&disk_to_dev(gd)->kobj, | |
026ec578 | 405 | new->disk_attributes); |
133fa8c7 ML |
406 | WARN_ON(ret); |
407 | } | |
1da177e4 | 408 | return 0; |
a8638622 ML |
409 | error4: |
410 | blk_cleanup_queue(new->rq); | |
411 | error3: | |
412 | put_disk(new->disk); | |
413 | error2: | |
414 | list_del(&new->list); | |
415 | error1: | |
416 | kfree(new); | |
417 | return ret; | |
1da177e4 LT |
418 | } |
419 | ||
420 | int del_mtd_blktrans_dev(struct mtd_blktrans_dev *old) | |
421 | { | |
048d8719 ML |
422 | unsigned long flags; |
423 | ||
b3561ea9 | 424 | if (mutex_trylock(&mtd_table_mutex)) { |
48b19268 | 425 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
426 | BUG(); |
427 | } | |
428 | ||
026ec578 ML |
429 | if (old->disk_attributes) |
430 | sysfs_remove_group(&disk_to_dev(old->disk)->kobj, | |
431 | old->disk_attributes); | |
432 | ||
dba76c03 ML |
433 | /* Stop new requests to arrive */ |
434 | del_gendisk(old->disk); | |
435 | ||
436 | ||
a8638622 ML |
437 | /* Stop the thread */ |
438 | kthread_stop(old->thread); | |
439 | ||
048d8719 ML |
440 | /* Kill current requests */ |
441 | spin_lock_irqsave(&old->queue_lock, flags); | |
442 | old->rq->queuedata = NULL; | |
443 | blk_start_queue(old->rq); | |
444 | spin_unlock_irqrestore(&old->queue_lock, flags); | |
048d8719 | 445 | |
008c751e ML |
446 | /* If the device is currently open, tell trans driver to close it, |
447 | then put mtd device, and don't touch it again */ | |
048d8719 | 448 | mutex_lock(&old->lock); |
008c751e ML |
449 | if (old->open) { |
450 | if (old->tr->release) | |
451 | old->tr->release(old); | |
452 | __put_mtd_device(old->mtd); | |
048d8719 ML |
453 | } |
454 | ||
048d8719 ML |
455 | old->mtd = NULL; |
456 | ||
457 | mutex_unlock(&old->lock); | |
458 | blktrans_dev_put(old); | |
1da177e4 LT |
459 | return 0; |
460 | } | |
461 | ||
462 | static void blktrans_notify_remove(struct mtd_info *mtd) | |
463 | { | |
71a928c0 CM |
464 | struct mtd_blktrans_ops *tr; |
465 | struct mtd_blktrans_dev *dev, *next; | |
1da177e4 | 466 | |
71a928c0 CM |
467 | list_for_each_entry(tr, &blktrans_majors, list) |
468 | list_for_each_entry_safe(dev, next, &tr->devs, list) | |
1da177e4 LT |
469 | if (dev->mtd == mtd) |
470 | tr->remove_dev(dev); | |
1da177e4 LT |
471 | } |
472 | ||
473 | static void blktrans_notify_add(struct mtd_info *mtd) | |
474 | { | |
71a928c0 | 475 | struct mtd_blktrans_ops *tr; |
1da177e4 LT |
476 | |
477 | if (mtd->type == MTD_ABSENT) | |
478 | return; | |
479 | ||
71a928c0 | 480 | list_for_each_entry(tr, &blktrans_majors, list) |
1da177e4 | 481 | tr->add_mtd(tr, mtd); |
1da177e4 LT |
482 | } |
483 | ||
484 | static struct mtd_notifier blktrans_notifier = { | |
485 | .add = blktrans_notify_add, | |
486 | .remove = blktrans_notify_remove, | |
487 | }; | |
97894cda | 488 | |
1da177e4 LT |
489 | int register_mtd_blktrans(struct mtd_blktrans_ops *tr) |
490 | { | |
f1332ba2 BH |
491 | struct mtd_info *mtd; |
492 | int ret; | |
1da177e4 | 493 | |
97894cda | 494 | /* Register the notifier if/when the first device type is |
1da177e4 LT |
495 | registered, to prevent the link/init ordering from fucking |
496 | us over. */ | |
497 | if (!blktrans_notifier.list.next) | |
498 | register_mtd_user(&blktrans_notifier); | |
499 | ||
1da177e4 | 500 | |
48b19268 | 501 | mutex_lock(&mtd_table_mutex); |
1da177e4 LT |
502 | |
503 | ret = register_blkdev(tr->major, tr->name); | |
6fe4c590 | 504 | if (ret < 0) { |
1da177e4 LT |
505 | printk(KERN_WARNING "Unable to register %s block device on major %d: %d\n", |
506 | tr->name, tr->major, ret); | |
48b19268 | 507 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
508 | return ret; |
509 | } | |
eae9acd1 | 510 | |
6fe4c590 FL |
511 | if (ret) |
512 | tr->major = ret; | |
513 | ||
19187672 | 514 | tr->blkshift = ffs(tr->blksize) - 1; |
1da177e4 | 515 | |
1da177e4 LT |
516 | INIT_LIST_HEAD(&tr->devs); |
517 | list_add(&tr->list, &blktrans_majors); | |
518 | ||
f1332ba2 BH |
519 | mtd_for_each_device(mtd) |
520 | if (mtd->type != MTD_ABSENT) | |
521 | tr->add_mtd(tr, mtd); | |
1da177e4 | 522 | |
48b19268 | 523 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
524 | return 0; |
525 | } | |
526 | ||
527 | int deregister_mtd_blktrans(struct mtd_blktrans_ops *tr) | |
528 | { | |
71a928c0 | 529 | struct mtd_blktrans_dev *dev, *next; |
1da177e4 | 530 | |
48b19268 | 531 | mutex_lock(&mtd_table_mutex); |
1da177e4 | 532 | |
1da177e4 LT |
533 | /* Remove it from the list of active majors */ |
534 | list_del(&tr->list); | |
535 | ||
71a928c0 | 536 | list_for_each_entry_safe(dev, next, &tr->devs, list) |
1da177e4 | 537 | tr->remove_dev(dev); |
1da177e4 | 538 | |
1da177e4 | 539 | unregister_blkdev(tr->major, tr->name); |
48b19268 | 540 | mutex_unlock(&mtd_table_mutex); |
1da177e4 | 541 | |
373ebfbf | 542 | BUG_ON(!list_empty(&tr->devs)); |
1da177e4 LT |
543 | return 0; |
544 | } | |
545 | ||
546 | static void __exit mtd_blktrans_exit(void) | |
547 | { | |
548 | /* No race here -- if someone's currently in register_mtd_blktrans | |
549 | we're screwed anyway. */ | |
550 | if (blktrans_notifier.list.next) | |
551 | unregister_mtd_user(&blktrans_notifier); | |
552 | } | |
553 | ||
554 | module_exit(mtd_blktrans_exit); | |
555 | ||
556 | EXPORT_SYMBOL_GPL(register_mtd_blktrans); | |
557 | EXPORT_SYMBOL_GPL(deregister_mtd_blktrans); | |
558 | EXPORT_SYMBOL_GPL(add_mtd_blktrans_dev); | |
559 | EXPORT_SYMBOL_GPL(del_mtd_blktrans_dev); | |
560 | ||
561 | MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>"); | |
562 | MODULE_LICENSE("GPL"); | |
563 | MODULE_DESCRIPTION("Common interface to block layer for MTD 'translation layers'"); |