Commit | Line | Data |
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9d54c8a3 EG |
1 | /* |
2 | * Copyright (c) 2014 Ezequiel Garcia | |
3 | * Copyright (c) 2011 Free Electrons | |
4 | * | |
5 | * Driver parameter handling strongly based on drivers/mtd/ubi/build.c | |
6 | * Copyright (c) International Business Machines Corp., 2006 | |
7 | * Copyright (c) Nokia Corporation, 2007 | |
8 | * Authors: Artem Bityutskiy, Frank Haverkamp | |
9 | * | |
10 | * This program is free software; you can redistribute it and/or modify | |
11 | * it under the terms of the GNU General Public License as published by | |
12 | * the Free Software Foundation, version 2. | |
13 | * | |
14 | * This program is distributed in the hope that it will be useful, | |
15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See | |
17 | * the GNU General Public License for more details. | |
18 | */ | |
19 | ||
20 | /* | |
21 | * Read-only block devices on top of UBI volumes | |
22 | * | |
23 | * A simple implementation to allow a block device to be layered on top of a | |
24 | * UBI volume. The implementation is provided by creating a static 1-to-1 | |
25 | * mapping between the block device and the UBI volume. | |
26 | * | |
27 | * The addressed byte is obtained from the addressed block sector, which is | |
28 | * mapped linearly into the corresponding LEB: | |
29 | * | |
30 | * LEB number = addressed byte / LEB size | |
31 | * | |
4d283ee2 AB |
32 | * This feature is compiled in the UBI core, and adds a 'block' parameter |
33 | * to allow early creation of block devices on top of UBI volumes. Runtime | |
34 | * block creation/removal for UBI volumes is provided through two UBI ioctls: | |
8af87188 | 35 | * UBI_IOCVOLCRBLK and UBI_IOCVOLRMBLK. |
9d54c8a3 EG |
36 | */ |
37 | ||
38 | #include <linux/module.h> | |
39 | #include <linux/init.h> | |
40 | #include <linux/err.h> | |
41 | #include <linux/kernel.h> | |
42 | #include <linux/list.h> | |
43 | #include <linux/mutex.h> | |
44 | #include <linux/slab.h> | |
9d54c8a3 EG |
45 | #include <linux/mtd/ubi.h> |
46 | #include <linux/workqueue.h> | |
47 | #include <linux/blkdev.h> | |
ff1f48ee | 48 | #include <linux/blk-mq.h> |
9d54c8a3 | 49 | #include <linux/hdreg.h> |
ff1f48ee | 50 | #include <linux/scatterlist.h> |
9d54c8a3 EG |
51 | #include <asm/div64.h> |
52 | ||
53 | #include "ubi-media.h" | |
54 | #include "ubi.h" | |
55 | ||
56 | /* Maximum number of supported devices */ | |
57 | #define UBIBLOCK_MAX_DEVICES 32 | |
58 | ||
59 | /* Maximum length of the 'block=' parameter */ | |
60 | #define UBIBLOCK_PARAM_LEN 63 | |
61 | ||
62 | /* Maximum number of comma-separated items in the 'block=' parameter */ | |
63 | #define UBIBLOCK_PARAM_COUNT 2 | |
64 | ||
65 | struct ubiblock_param { | |
66 | int ubi_num; | |
67 | int vol_id; | |
68 | char name[UBIBLOCK_PARAM_LEN+1]; | |
69 | }; | |
70 | ||
ff1f48ee RW |
71 | struct ubiblock_pdu { |
72 | struct work_struct work; | |
73 | struct ubi_sgl usgl; | |
74 | }; | |
75 | ||
9d54c8a3 EG |
76 | /* Numbers of elements set in the @ubiblock_param array */ |
77 | static int ubiblock_devs __initdata; | |
78 | ||
79 | /* MTD devices specification parameters */ | |
80 | static struct ubiblock_param ubiblock_param[UBIBLOCK_MAX_DEVICES] __initdata; | |
81 | ||
82 | struct ubiblock { | |
83 | struct ubi_volume_desc *desc; | |
84 | int ubi_num; | |
85 | int vol_id; | |
86 | int refcnt; | |
87 | int leb_size; | |
88 | ||
89 | struct gendisk *gd; | |
90 | struct request_queue *rq; | |
91 | ||
92 | struct workqueue_struct *wq; | |
9d54c8a3 EG |
93 | |
94 | struct mutex dev_mutex; | |
9d54c8a3 | 95 | struct list_head list; |
ff1f48ee | 96 | struct blk_mq_tag_set tag_set; |
9d54c8a3 EG |
97 | }; |
98 | ||
99 | /* Linked list of all ubiblock instances */ | |
100 | static LIST_HEAD(ubiblock_devices); | |
101 | static DEFINE_MUTEX(devices_mutex); | |
102 | static int ubiblock_major; | |
103 | ||
104 | static int __init ubiblock_set_param(const char *val, | |
105 | const struct kernel_param *kp) | |
106 | { | |
107 | int i, ret; | |
108 | size_t len; | |
109 | struct ubiblock_param *param; | |
110 | char buf[UBIBLOCK_PARAM_LEN]; | |
111 | char *pbuf = &buf[0]; | |
112 | char *tokens[UBIBLOCK_PARAM_COUNT]; | |
113 | ||
114 | if (!val) | |
115 | return -EINVAL; | |
116 | ||
117 | len = strnlen(val, UBIBLOCK_PARAM_LEN); | |
118 | if (len == 0) { | |
32608703 | 119 | pr_warn("UBI: block: empty 'block=' parameter - ignored\n"); |
9d54c8a3 EG |
120 | return 0; |
121 | } | |
122 | ||
123 | if (len == UBIBLOCK_PARAM_LEN) { | |
32608703 TB |
124 | pr_err("UBI: block: parameter \"%s\" is too long, max. is %d\n", |
125 | val, UBIBLOCK_PARAM_LEN); | |
9d54c8a3 EG |
126 | return -EINVAL; |
127 | } | |
128 | ||
129 | strcpy(buf, val); | |
130 | ||
131 | /* Get rid of the final newline */ | |
132 | if (buf[len - 1] == '\n') | |
133 | buf[len - 1] = '\0'; | |
134 | ||
135 | for (i = 0; i < UBIBLOCK_PARAM_COUNT; i++) | |
136 | tokens[i] = strsep(&pbuf, ","); | |
137 | ||
138 | param = &ubiblock_param[ubiblock_devs]; | |
139 | if (tokens[1]) { | |
140 | /* Two parameters: can be 'ubi, vol_id' or 'ubi, vol_name' */ | |
141 | ret = kstrtoint(tokens[0], 10, ¶m->ubi_num); | |
142 | if (ret < 0) | |
143 | return -EINVAL; | |
144 | ||
145 | /* Second param can be a number or a name */ | |
146 | ret = kstrtoint(tokens[1], 10, ¶m->vol_id); | |
147 | if (ret < 0) { | |
148 | param->vol_id = -1; | |
149 | strcpy(param->name, tokens[1]); | |
150 | } | |
151 | ||
152 | } else { | |
153 | /* One parameter: must be device path */ | |
154 | strcpy(param->name, tokens[0]); | |
155 | param->ubi_num = -1; | |
156 | param->vol_id = -1; | |
157 | } | |
158 | ||
159 | ubiblock_devs++; | |
160 | ||
161 | return 0; | |
162 | } | |
163 | ||
d56030ac | 164 | static struct kernel_param_ops ubiblock_param_ops = { |
9d54c8a3 EG |
165 | .set = ubiblock_set_param, |
166 | }; | |
167 | module_param_cb(block, &ubiblock_param_ops, NULL, 0); | |
168 | MODULE_PARM_DESC(block, "Attach block devices to UBI volumes. Parameter format: block=<path|dev,num|dev,name>.\n" | |
169 | "Multiple \"block\" parameters may be specified.\n" | |
170 | "UBI volumes may be specified by their number, name, or path to the device node.\n" | |
171 | "Examples\n" | |
172 | "Using the UBI volume path:\n" | |
173 | "ubi.block=/dev/ubi0_0\n" | |
174 | "Using the UBI device, and the volume name:\n" | |
175 | "ubi.block=0,rootfs\n" | |
176 | "Using both UBI device number and UBI volume number:\n" | |
177 | "ubi.block=0,0\n"); | |
178 | ||
179 | static struct ubiblock *find_dev_nolock(int ubi_num, int vol_id) | |
180 | { | |
181 | struct ubiblock *dev; | |
182 | ||
183 | list_for_each_entry(dev, &ubiblock_devices, list) | |
184 | if (dev->ubi_num == ubi_num && dev->vol_id == vol_id) | |
185 | return dev; | |
186 | return NULL; | |
187 | } | |
188 | ||
ff1f48ee | 189 | static int ubiblock_read(struct ubiblock_pdu *pdu) |
9d54c8a3 | 190 | { |
ff1f48ee RW |
191 | int ret, leb, offset, bytes_left, to_read; |
192 | u64 pos; | |
193 | struct request *req = blk_mq_rq_from_pdu(pdu); | |
194 | struct ubiblock *dev = req->q->queuedata; | |
9d54c8a3 | 195 | |
ff1f48ee RW |
196 | to_read = blk_rq_bytes(req); |
197 | pos = blk_rq_pos(req) << 9; | |
9d54c8a3 EG |
198 | |
199 | /* Get LEB:offset address to read from */ | |
200 | offset = do_div(pos, dev->leb_size); | |
201 | leb = pos; | |
ff1f48ee | 202 | bytes_left = to_read; |
9d54c8a3 EG |
203 | |
204 | while (bytes_left) { | |
205 | /* | |
206 | * We can only read one LEB at a time. Therefore if the read | |
207 | * length is larger than one LEB size, we split the operation. | |
208 | */ | |
209 | if (offset + to_read > dev->leb_size) | |
210 | to_read = dev->leb_size - offset; | |
211 | ||
ff1f48ee RW |
212 | ret = ubi_read_sg(dev->desc, leb, &pdu->usgl, offset, to_read); |
213 | if (ret < 0) | |
9d54c8a3 EG |
214 | return ret; |
215 | ||
9d54c8a3 EG |
216 | bytes_left -= to_read; |
217 | to_read = bytes_left; | |
218 | leb += 1; | |
219 | offset = 0; | |
220 | } | |
221 | return 0; | |
222 | } | |
223 | ||
9d54c8a3 EG |
224 | static int ubiblock_open(struct block_device *bdev, fmode_t mode) |
225 | { | |
226 | struct ubiblock *dev = bdev->bd_disk->private_data; | |
227 | int ret; | |
228 | ||
229 | mutex_lock(&dev->dev_mutex); | |
230 | if (dev->refcnt > 0) { | |
231 | /* | |
232 | * The volume is already open, just increase the reference | |
233 | * counter. | |
234 | */ | |
235 | goto out_done; | |
236 | } | |
237 | ||
238 | /* | |
239 | * We want users to be aware they should only mount us as read-only. | |
240 | * It's just a paranoid check, as write requests will get rejected | |
241 | * in any case. | |
242 | */ | |
243 | if (mode & FMODE_WRITE) { | |
244 | ret = -EPERM; | |
245 | goto out_unlock; | |
246 | } | |
247 | ||
248 | dev->desc = ubi_open_volume(dev->ubi_num, dev->vol_id, UBI_READONLY); | |
249 | if (IS_ERR(dev->desc)) { | |
32608703 TB |
250 | dev_err(disk_to_dev(dev->gd), "failed to open ubi volume %d_%d", |
251 | dev->ubi_num, dev->vol_id); | |
9d54c8a3 EG |
252 | ret = PTR_ERR(dev->desc); |
253 | dev->desc = NULL; | |
254 | goto out_unlock; | |
255 | } | |
256 | ||
257 | out_done: | |
258 | dev->refcnt++; | |
259 | mutex_unlock(&dev->dev_mutex); | |
260 | return 0; | |
261 | ||
262 | out_unlock: | |
263 | mutex_unlock(&dev->dev_mutex); | |
264 | return ret; | |
265 | } | |
266 | ||
267 | static void ubiblock_release(struct gendisk *gd, fmode_t mode) | |
268 | { | |
269 | struct ubiblock *dev = gd->private_data; | |
270 | ||
271 | mutex_lock(&dev->dev_mutex); | |
272 | dev->refcnt--; | |
273 | if (dev->refcnt == 0) { | |
274 | ubi_close_volume(dev->desc); | |
275 | dev->desc = NULL; | |
276 | } | |
277 | mutex_unlock(&dev->dev_mutex); | |
278 | } | |
279 | ||
280 | static int ubiblock_getgeo(struct block_device *bdev, struct hd_geometry *geo) | |
281 | { | |
282 | /* Some tools might require this information */ | |
283 | geo->heads = 1; | |
284 | geo->cylinders = 1; | |
285 | geo->sectors = get_capacity(bdev->bd_disk); | |
286 | geo->start = 0; | |
287 | return 0; | |
288 | } | |
289 | ||
290 | static const struct block_device_operations ubiblock_ops = { | |
291 | .owner = THIS_MODULE, | |
292 | .open = ubiblock_open, | |
293 | .release = ubiblock_release, | |
294 | .getgeo = ubiblock_getgeo, | |
295 | }; | |
296 | ||
ff1f48ee RW |
297 | static void ubiblock_do_work(struct work_struct *work) |
298 | { | |
299 | int ret; | |
300 | struct ubiblock_pdu *pdu = container_of(work, struct ubiblock_pdu, work); | |
301 | struct request *req = blk_mq_rq_from_pdu(pdu); | |
302 | ||
303 | blk_mq_start_request(req); | |
832b52a1 RW |
304 | |
305 | /* | |
306 | * It is safe to ignore the return value of blk_rq_map_sg() because | |
307 | * the number of sg entries is limited to UBI_MAX_SG_COUNT | |
308 | * and ubi_read_sg() will check that limit. | |
309 | */ | |
ff1f48ee RW |
310 | blk_rq_map_sg(req->q, req, pdu->usgl.sg); |
311 | ||
312 | ret = ubiblock_read(pdu); | |
313 | blk_mq_end_request(req, ret); | |
314 | } | |
315 | ||
316 | static int ubiblock_queue_rq(struct blk_mq_hw_ctx *hctx, | |
317 | const struct blk_mq_queue_data *bd) | |
318 | { | |
319 | struct request *req = bd->rq; | |
320 | struct ubiblock *dev = hctx->queue->queuedata; | |
321 | struct ubiblock_pdu *pdu = blk_mq_rq_to_pdu(req); | |
322 | ||
323 | if (req->cmd_type != REQ_TYPE_FS) | |
324 | return BLK_MQ_RQ_QUEUE_ERROR; | |
325 | ||
326 | if (rq_data_dir(req) != READ) | |
327 | return BLK_MQ_RQ_QUEUE_ERROR; /* Write not implemented */ | |
328 | ||
329 | ubi_sgl_init(&pdu->usgl); | |
330 | queue_work(dev->wq, &pdu->work); | |
331 | ||
332 | return BLK_MQ_RQ_QUEUE_OK; | |
333 | } | |
334 | ||
335 | static int ubiblock_init_request(void *data, struct request *req, | |
336 | unsigned int hctx_idx, | |
337 | unsigned int request_idx, | |
338 | unsigned int numa_node) | |
339 | { | |
340 | struct ubiblock_pdu *pdu = blk_mq_rq_to_pdu(req); | |
341 | ||
342 | sg_init_table(pdu->usgl.sg, UBI_MAX_SG_COUNT); | |
343 | INIT_WORK(&pdu->work, ubiblock_do_work); | |
344 | ||
345 | return 0; | |
346 | } | |
347 | ||
348 | static struct blk_mq_ops ubiblock_mq_ops = { | |
349 | .queue_rq = ubiblock_queue_rq, | |
350 | .init_request = ubiblock_init_request, | |
351 | .map_queue = blk_mq_map_queue, | |
352 | }; | |
353 | ||
4d283ee2 | 354 | int ubiblock_create(struct ubi_volume_info *vi) |
9d54c8a3 EG |
355 | { |
356 | struct ubiblock *dev; | |
357 | struct gendisk *gd; | |
978d6496 | 358 | u64 disk_capacity = vi->used_bytes >> 9; |
9d54c8a3 EG |
359 | int ret; |
360 | ||
4df38926 RW |
361 | if ((sector_t)disk_capacity != disk_capacity) |
362 | return -EFBIG; | |
9d54c8a3 EG |
363 | /* Check that the volume isn't already handled */ |
364 | mutex_lock(&devices_mutex); | |
365 | if (find_dev_nolock(vi->ubi_num, vi->vol_id)) { | |
366 | mutex_unlock(&devices_mutex); | |
367 | return -EEXIST; | |
368 | } | |
369 | mutex_unlock(&devices_mutex); | |
370 | ||
371 | dev = kzalloc(sizeof(struct ubiblock), GFP_KERNEL); | |
372 | if (!dev) | |
373 | return -ENOMEM; | |
374 | ||
375 | mutex_init(&dev->dev_mutex); | |
376 | ||
377 | dev->ubi_num = vi->ubi_num; | |
378 | dev->vol_id = vi->vol_id; | |
379 | dev->leb_size = vi->usable_leb_size; | |
380 | ||
381 | /* Initialize the gendisk of this ubiblock device */ | |
382 | gd = alloc_disk(1); | |
383 | if (!gd) { | |
32608703 | 384 | pr_err("UBI: block: alloc_disk failed"); |
9d54c8a3 EG |
385 | ret = -ENODEV; |
386 | goto out_free_dev; | |
387 | } | |
388 | ||
389 | gd->fops = &ubiblock_ops; | |
390 | gd->major = ubiblock_major; | |
391 | gd->first_minor = dev->ubi_num * UBI_MAX_VOLUMES + dev->vol_id; | |
392 | gd->private_data = dev; | |
393 | sprintf(gd->disk_name, "ubiblock%d_%d", dev->ubi_num, dev->vol_id); | |
9d54c8a3 EG |
394 | set_capacity(gd, disk_capacity); |
395 | dev->gd = gd; | |
396 | ||
ff1f48ee RW |
397 | dev->tag_set.ops = &ubiblock_mq_ops; |
398 | dev->tag_set.queue_depth = 64; | |
399 | dev->tag_set.numa_node = NUMA_NO_NODE; | |
400 | dev->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; | |
401 | dev->tag_set.cmd_size = sizeof(struct ubiblock_pdu); | |
402 | dev->tag_set.driver_data = dev; | |
403 | dev->tag_set.nr_hw_queues = 1; | |
404 | ||
405 | ret = blk_mq_alloc_tag_set(&dev->tag_set); | |
406 | if (ret) { | |
407 | dev_err(disk_to_dev(dev->gd), "blk_mq_alloc_tag_set failed"); | |
408 | goto out_put_disk; | |
409 | } | |
410 | ||
411 | dev->rq = blk_mq_init_queue(&dev->tag_set); | |
8168b9bb | 412 | if (IS_ERR(dev->rq)) { |
ff1f48ee | 413 | dev_err(disk_to_dev(gd), "blk_mq_init_queue failed"); |
8168b9bb | 414 | ret = PTR_ERR(dev->rq); |
ff1f48ee | 415 | goto out_free_tags; |
9d54c8a3 | 416 | } |
ff1f48ee | 417 | blk_queue_max_segments(dev->rq, UBI_MAX_SG_COUNT); |
9d54c8a3 EG |
418 | |
419 | dev->rq->queuedata = dev; | |
420 | dev->gd->queue = dev->rq; | |
421 | ||
422 | /* | |
423 | * Create one workqueue per volume (per registered block device). | |
424 | * Rembember workqueues are cheap, they're not threads. | |
425 | */ | |
bebfef15 | 426 | dev->wq = alloc_workqueue("%s", 0, 0, gd->disk_name); |
151d6b21 HS |
427 | if (!dev->wq) { |
428 | ret = -ENOMEM; | |
9d54c8a3 | 429 | goto out_free_queue; |
151d6b21 | 430 | } |
9d54c8a3 EG |
431 | |
432 | mutex_lock(&devices_mutex); | |
433 | list_add_tail(&dev->list, &ubiblock_devices); | |
434 | mutex_unlock(&devices_mutex); | |
435 | ||
436 | /* Must be the last step: anyone can call file ops from now on */ | |
437 | add_disk(dev->gd); | |
32608703 TB |
438 | dev_info(disk_to_dev(dev->gd), "created from ubi%d:%d(%s)", |
439 | dev->ubi_num, dev->vol_id, vi->name); | |
9d54c8a3 EG |
440 | return 0; |
441 | ||
442 | out_free_queue: | |
443 | blk_cleanup_queue(dev->rq); | |
ff1f48ee RW |
444 | out_free_tags: |
445 | blk_mq_free_tag_set(&dev->tag_set); | |
9d54c8a3 EG |
446 | out_put_disk: |
447 | put_disk(dev->gd); | |
448 | out_free_dev: | |
449 | kfree(dev); | |
450 | ||
451 | return ret; | |
452 | } | |
453 | ||
454 | static void ubiblock_cleanup(struct ubiblock *dev) | |
455 | { | |
ff1f48ee | 456 | /* Stop new requests to arrive */ |
9d54c8a3 | 457 | del_gendisk(dev->gd); |
ff1f48ee RW |
458 | /* Flush pending work */ |
459 | destroy_workqueue(dev->wq); | |
460 | /* Finally destroy the blk queue */ | |
9d54c8a3 | 461 | blk_cleanup_queue(dev->rq); |
ff1f48ee | 462 | blk_mq_free_tag_set(&dev->tag_set); |
32608703 | 463 | dev_info(disk_to_dev(dev->gd), "released"); |
9d54c8a3 EG |
464 | put_disk(dev->gd); |
465 | } | |
466 | ||
4d283ee2 | 467 | int ubiblock_remove(struct ubi_volume_info *vi) |
9d54c8a3 EG |
468 | { |
469 | struct ubiblock *dev; | |
470 | ||
471 | mutex_lock(&devices_mutex); | |
472 | dev = find_dev_nolock(vi->ubi_num, vi->vol_id); | |
473 | if (!dev) { | |
474 | mutex_unlock(&devices_mutex); | |
475 | return -ENODEV; | |
476 | } | |
477 | ||
478 | /* Found a device, let's lock it so we can check if it's busy */ | |
479 | mutex_lock(&dev->dev_mutex); | |
480 | if (dev->refcnt > 0) { | |
481 | mutex_unlock(&dev->dev_mutex); | |
482 | mutex_unlock(&devices_mutex); | |
483 | return -EBUSY; | |
484 | } | |
485 | ||
486 | /* Remove from device list */ | |
487 | list_del(&dev->list); | |
488 | mutex_unlock(&devices_mutex); | |
489 | ||
9d54c8a3 EG |
490 | ubiblock_cleanup(dev); |
491 | mutex_unlock(&dev->dev_mutex); | |
492 | kfree(dev); | |
493 | return 0; | |
494 | } | |
495 | ||
495f2bf6 | 496 | static int ubiblock_resize(struct ubi_volume_info *vi) |
9d54c8a3 EG |
497 | { |
498 | struct ubiblock *dev; | |
978d6496 | 499 | u64 disk_capacity = vi->used_bytes >> 9; |
9d54c8a3 EG |
500 | |
501 | /* | |
502 | * Need to lock the device list until we stop using the device, | |
4d283ee2 AB |
503 | * otherwise the device struct might get released in |
504 | * 'ubiblock_remove()'. | |
9d54c8a3 EG |
505 | */ |
506 | mutex_lock(&devices_mutex); | |
507 | dev = find_dev_nolock(vi->ubi_num, vi->vol_id); | |
508 | if (!dev) { | |
509 | mutex_unlock(&devices_mutex); | |
495f2bf6 | 510 | return -ENODEV; |
9d54c8a3 | 511 | } |
3df77072 CIK |
512 | if ((sector_t)disk_capacity != disk_capacity) { |
513 | mutex_unlock(&devices_mutex); | |
32608703 TB |
514 | dev_warn(disk_to_dev(dev->gd), "the volume is too big (%d LEBs), cannot resize", |
515 | vi->size); | |
3df77072 CIK |
516 | return -EFBIG; |
517 | } | |
9d54c8a3 EG |
518 | |
519 | mutex_lock(&dev->dev_mutex); | |
06d9c290 EG |
520 | |
521 | if (get_capacity(dev->gd) != disk_capacity) { | |
522 | set_capacity(dev->gd, disk_capacity); | |
32608703 TB |
523 | dev_info(disk_to_dev(dev->gd), "resized to %lld bytes", |
524 | vi->used_bytes); | |
06d9c290 | 525 | } |
9d54c8a3 EG |
526 | mutex_unlock(&dev->dev_mutex); |
527 | mutex_unlock(&devices_mutex); | |
495f2bf6 | 528 | return 0; |
9d54c8a3 EG |
529 | } |
530 | ||
531 | static int ubiblock_notify(struct notifier_block *nb, | |
532 | unsigned long notification_type, void *ns_ptr) | |
533 | { | |
534 | struct ubi_notification *nt = ns_ptr; | |
535 | ||
536 | switch (notification_type) { | |
537 | case UBI_VOLUME_ADDED: | |
538 | /* | |
4d283ee2 | 539 | * We want to enforce explicit block device creation for |
9d54c8a3 EG |
540 | * volumes, so when a volume is added we do nothing. |
541 | */ | |
542 | break; | |
543 | case UBI_VOLUME_REMOVED: | |
4d283ee2 | 544 | ubiblock_remove(&nt->vi); |
9d54c8a3 EG |
545 | break; |
546 | case UBI_VOLUME_RESIZED: | |
547 | ubiblock_resize(&nt->vi); | |
548 | break; | |
06d9c290 EG |
549 | case UBI_VOLUME_UPDATED: |
550 | /* | |
551 | * If the volume is static, a content update might mean the | |
552 | * size (i.e. used_bytes) was also changed. | |
553 | */ | |
554 | if (nt->vi.vol_type == UBI_STATIC_VOLUME) | |
555 | ubiblock_resize(&nt->vi); | |
556 | break; | |
9d54c8a3 EG |
557 | default: |
558 | break; | |
559 | } | |
560 | return NOTIFY_OK; | |
561 | } | |
562 | ||
563 | static struct notifier_block ubiblock_notifier = { | |
564 | .notifier_call = ubiblock_notify, | |
565 | }; | |
566 | ||
567 | static struct ubi_volume_desc * __init | |
568 | open_volume_desc(const char *name, int ubi_num, int vol_id) | |
569 | { | |
570 | if (ubi_num == -1) | |
571 | /* No ubi num, name must be a vol device path */ | |
572 | return ubi_open_volume_path(name, UBI_READONLY); | |
573 | else if (vol_id == -1) | |
574 | /* No vol_id, must be vol_name */ | |
575 | return ubi_open_volume_nm(ubi_num, name, UBI_READONLY); | |
576 | else | |
577 | return ubi_open_volume(ubi_num, vol_id, UBI_READONLY); | |
578 | } | |
579 | ||
1440061b | 580 | static void __init ubiblock_create_from_param(void) |
9d54c8a3 | 581 | { |
1440061b | 582 | int i, ret = 0; |
9d54c8a3 EG |
583 | struct ubiblock_param *p; |
584 | struct ubi_volume_desc *desc; | |
585 | struct ubi_volume_info vi; | |
586 | ||
1440061b DE |
587 | /* |
588 | * If there is an error creating one of the ubiblocks, continue on to | |
589 | * create the following ubiblocks. This helps in a circumstance where | |
590 | * the kernel command-line specifies multiple block devices and some | |
591 | * may be broken, but we still want the working ones to come up. | |
592 | */ | |
9d54c8a3 EG |
593 | for (i = 0; i < ubiblock_devs; i++) { |
594 | p = &ubiblock_param[i]; | |
595 | ||
596 | desc = open_volume_desc(p->name, p->ubi_num, p->vol_id); | |
597 | if (IS_ERR(desc)) { | |
1440061b DE |
598 | pr_err( |
599 | "UBI: block: can't open volume on ubi%d_%d, err=%ld", | |
600 | p->ubi_num, p->vol_id, PTR_ERR(desc)); | |
601 | continue; | |
9d54c8a3 EG |
602 | } |
603 | ||
604 | ubi_get_volume_info(desc, &vi); | |
605 | ubi_close_volume(desc); | |
606 | ||
4d283ee2 | 607 | ret = ubiblock_create(&vi); |
9d54c8a3 | 608 | if (ret) { |
1440061b DE |
609 | pr_err( |
610 | "UBI: block: can't add '%s' volume on ubi%d_%d, err=%d", | |
611 | vi.name, p->ubi_num, p->vol_id, ret); | |
612 | continue; | |
9d54c8a3 EG |
613 | } |
614 | } | |
9d54c8a3 EG |
615 | } |
616 | ||
4d283ee2 | 617 | static void ubiblock_remove_all(void) |
9d54c8a3 EG |
618 | { |
619 | struct ubiblock *next; | |
620 | struct ubiblock *dev; | |
621 | ||
622 | list_for_each_entry_safe(dev, next, &ubiblock_devices, list) { | |
9d54c8a3 EG |
623 | /* The module is being forcefully removed */ |
624 | WARN_ON(dev->desc); | |
625 | /* Remove from device list */ | |
626 | list_del(&dev->list); | |
627 | ubiblock_cleanup(dev); | |
628 | kfree(dev); | |
629 | } | |
630 | } | |
631 | ||
632 | int __init ubiblock_init(void) | |
633 | { | |
634 | int ret; | |
635 | ||
636 | ubiblock_major = register_blkdev(0, "ubiblock"); | |
637 | if (ubiblock_major < 0) | |
638 | return ubiblock_major; | |
639 | ||
1440061b DE |
640 | /* |
641 | * Attach block devices from 'block=' module param. | |
642 | * Even if one block device in the param list fails to come up, | |
643 | * still allow the module to load and leave any others up. | |
644 | */ | |
645 | ubiblock_create_from_param(); | |
9d54c8a3 EG |
646 | |
647 | /* | |
4d283ee2 AB |
648 | * Block devices are only created upon user requests, so we ignore |
649 | * existing volumes. | |
9d54c8a3 EG |
650 | */ |
651 | ret = ubi_register_volume_notifier(&ubiblock_notifier, 1); | |
652 | if (ret) | |
653 | goto err_unreg; | |
654 | return 0; | |
655 | ||
656 | err_unreg: | |
657 | unregister_blkdev(ubiblock_major, "ubiblock"); | |
4d283ee2 | 658 | ubiblock_remove_all(); |
9d54c8a3 EG |
659 | return ret; |
660 | } | |
661 | ||
662 | void __exit ubiblock_exit(void) | |
663 | { | |
664 | ubi_unregister_volume_notifier(&ubiblock_notifier); | |
4d283ee2 | 665 | ubiblock_remove_all(); |
9d54c8a3 EG |
666 | unregister_blkdev(ubiblock_major, "ubiblock"); |
667 | } |