xref: /openbmc/linux/drivers/mtd/ubi/vmt.c (revision c21b37f6)
1 /*
2  * Copyright (c) International Business Machines Corp., 2006
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation;  either version 2 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
12  * the GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17  *
18  * Author: Artem Bityutskiy (Битюцкий Артём)
19  */
20 
21 /*
22  * This file contains implementation of volume creation, deletion, updating and
23  * resizing.
24  */
25 
26 #include <linux/err.h>
27 #include <asm/div64.h>
28 #include "ubi.h"
29 
30 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
31 static void paranoid_check_volumes(struct ubi_device *ubi);
32 #else
33 #define paranoid_check_volumes(ubi)
34 #endif
35 
36 static ssize_t vol_attribute_show(struct device *dev,
37 				  struct device_attribute *attr, char *buf);
38 
39 /* Device attributes corresponding to files in '/<sysfs>/class/ubi/ubiX_Y' */
40 static struct device_attribute vol_reserved_ebs =
41 	__ATTR(reserved_ebs, S_IRUGO, vol_attribute_show, NULL);
42 static struct device_attribute vol_type =
43 	__ATTR(type, S_IRUGO, vol_attribute_show, NULL);
44 static struct device_attribute vol_name =
45 	__ATTR(name, S_IRUGO, vol_attribute_show, NULL);
46 static struct device_attribute vol_corrupted =
47 	__ATTR(corrupted, S_IRUGO, vol_attribute_show, NULL);
48 static struct device_attribute vol_alignment =
49 	__ATTR(alignment, S_IRUGO, vol_attribute_show, NULL);
50 static struct device_attribute vol_usable_eb_size =
51 	__ATTR(usable_eb_size, S_IRUGO, vol_attribute_show, NULL);
52 static struct device_attribute vol_data_bytes =
53 	__ATTR(data_bytes, S_IRUGO, vol_attribute_show, NULL);
54 static struct device_attribute vol_upd_marker =
55 	__ATTR(upd_marker, S_IRUGO, vol_attribute_show, NULL);
56 
57 /*
58  * "Show" method for files in '/<sysfs>/class/ubi/ubiX_Y/'.
59  *
60  * Consider a situation:
61  * A. process 1 opens a sysfs file related to volume Y, say
62  *    /<sysfs>/class/ubi/ubiX_Y/reserved_ebs;
63  * B. process 2 removes volume Y;
64  * C. process 1 starts reading the /<sysfs>/class/ubi/ubiX_Y/reserved_ebs file;
65  *
66  * What we want to do in a situation like that is to return error when the file
67  * is read. This is done by means of the 'removed' flag and the 'vol_lock' of
68  * the UBI volume description object.
69  */
70 static ssize_t vol_attribute_show(struct device *dev,
71 				  struct device_attribute *attr, char *buf)
72 {
73 	int ret;
74 	struct ubi_volume *vol = container_of(dev, struct ubi_volume, dev);
75 
76 	spin_lock(&vol->ubi->volumes_lock);
77 	if (vol->removed) {
78 		spin_unlock(&vol->ubi->volumes_lock);
79 		return -ENODEV;
80 	}
81 	if (attr == &vol_reserved_ebs)
82 		ret = sprintf(buf, "%d\n", vol->reserved_pebs);
83 	else if (attr == &vol_type) {
84 		const char *tp;
85 		tp = vol->vol_type == UBI_DYNAMIC_VOLUME ? "dynamic" : "static";
86 		ret = sprintf(buf, "%s\n", tp);
87 	} else if (attr == &vol_name)
88 		ret = sprintf(buf, "%s\n", vol->name);
89 	else if (attr == &vol_corrupted)
90 		ret = sprintf(buf, "%d\n", vol->corrupted);
91 	else if (attr == &vol_alignment)
92 		ret = sprintf(buf, "%d\n", vol->alignment);
93 	else if (attr == &vol_usable_eb_size) {
94 		ret = sprintf(buf, "%d\n", vol->usable_leb_size);
95 	} else if (attr == &vol_data_bytes)
96 		ret = sprintf(buf, "%lld\n", vol->used_bytes);
97 	else if (attr == &vol_upd_marker)
98 		ret = sprintf(buf, "%d\n", vol->upd_marker);
99 	else
100 		BUG();
101 	spin_unlock(&vol->ubi->volumes_lock);
102 	return ret;
103 }
104 
105 /* Release method for volume devices */
106 static void vol_release(struct device *dev)
107 {
108 	struct ubi_volume *vol = container_of(dev, struct ubi_volume, dev);
109 	ubi_assert(vol->removed);
110 	kfree(vol);
111 }
112 
113 /**
114  * volume_sysfs_init - initialize sysfs for new volume.
115  * @ubi: UBI device description object
116  * @vol: volume description object
117  *
118  * This function returns zero in case of success and a negative error code in
119  * case of failure.
120  *
121  * Note, this function does not free allocated resources in case of failure -
122  * the caller does it. This is because this would cause release() here and the
123  * caller would oops.
124  */
125 static int volume_sysfs_init(struct ubi_device *ubi, struct ubi_volume *vol)
126 {
127 	int err;
128 
129 	err = device_create_file(&vol->dev, &vol_reserved_ebs);
130 	if (err)
131 		return err;
132 	err = device_create_file(&vol->dev, &vol_type);
133 	if (err)
134 		return err;
135 	err = device_create_file(&vol->dev, &vol_name);
136 	if (err)
137 		return err;
138 	err = device_create_file(&vol->dev, &vol_corrupted);
139 	if (err)
140 		return err;
141 	err = device_create_file(&vol->dev, &vol_alignment);
142 	if (err)
143 		return err;
144 	err = device_create_file(&vol->dev, &vol_usable_eb_size);
145 	if (err)
146 		return err;
147 	err = device_create_file(&vol->dev, &vol_data_bytes);
148 	if (err)
149 		return err;
150 	err = device_create_file(&vol->dev, &vol_upd_marker);
151 	if (err)
152 		return err;
153 	return 0;
154 }
155 
156 /**
157  * volume_sysfs_close - close sysfs for a volume.
158  * @vol: volume description object
159  */
160 static void volume_sysfs_close(struct ubi_volume *vol)
161 {
162 	device_remove_file(&vol->dev, &vol_upd_marker);
163 	device_remove_file(&vol->dev, &vol_data_bytes);
164 	device_remove_file(&vol->dev, &vol_usable_eb_size);
165 	device_remove_file(&vol->dev, &vol_alignment);
166 	device_remove_file(&vol->dev, &vol_corrupted);
167 	device_remove_file(&vol->dev, &vol_name);
168 	device_remove_file(&vol->dev, &vol_type);
169 	device_remove_file(&vol->dev, &vol_reserved_ebs);
170 	device_unregister(&vol->dev);
171 }
172 
173 /**
174  * ubi_create_volume - create volume.
175  * @ubi: UBI device description object
176  * @req: volume creation request
177  *
178  * This function creates volume described by @req. If @req->vol_id id
179  * %UBI_VOL_NUM_AUTO, this function automatically assigne ID to the new volume
180  * and saves it in @req->vol_id. Returns zero in case of success and a negative
181  * error code in case of failure.
182  */
183 int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req)
184 {
185 	int i, err, vol_id = req->vol_id;
186 	struct ubi_volume *vol;
187 	struct ubi_vtbl_record vtbl_rec;
188 	uint64_t bytes;
189 
190 	if (ubi->ro_mode)
191 		return -EROFS;
192 
193 	vol = kzalloc(sizeof(struct ubi_volume), GFP_KERNEL);
194 	if (!vol)
195 		return -ENOMEM;
196 
197 	spin_lock(&ubi->volumes_lock);
198 
199 	if (vol_id == UBI_VOL_NUM_AUTO) {
200 		/* Find unused volume ID */
201 		dbg_msg("search for vacant volume ID");
202 		for (i = 0; i < ubi->vtbl_slots; i++)
203 			if (!ubi->volumes[i]) {
204 				vol_id = i;
205 				break;
206 			}
207 
208 		if (vol_id == UBI_VOL_NUM_AUTO) {
209 			dbg_err("out of volume IDs");
210 			err = -ENFILE;
211 			goto out_unlock;
212 		}
213 		req->vol_id = vol_id;
214 	}
215 
216 	dbg_msg("volume ID %d, %llu bytes, type %d, name %s",
217 		vol_id, (unsigned long long)req->bytes,
218 		(int)req->vol_type, req->name);
219 
220 	/* Ensure that this volume does not exist */
221 	err = -EEXIST;
222 	if (ubi->volumes[vol_id]) {
223 		dbg_err("volume %d already exists", vol_id);
224 		goto out_unlock;
225 	}
226 
227 	/* Ensure that the name is unique */
228 	for (i = 0; i < ubi->vtbl_slots; i++)
229 		if (ubi->volumes[i] &&
230 		    ubi->volumes[i]->name_len == req->name_len &&
231 		    !strcmp(ubi->volumes[i]->name, req->name)) {
232 			dbg_err("volume \"%s\" exists (ID %d)", req->name, i);
233 			goto out_unlock;
234 		}
235 
236         /* Calculate how many eraseblocks are requested */
237 	vol->usable_leb_size = ubi->leb_size - ubi->leb_size % req->alignment;
238 	bytes = req->bytes;
239 	if (do_div(bytes, vol->usable_leb_size))
240 		vol->reserved_pebs = 1;
241 	vol->reserved_pebs += bytes;
242 
243 	/* Reserve physical eraseblocks */
244 	if (vol->reserved_pebs > ubi->avail_pebs) {
245 		dbg_err("not enough PEBs, only %d available", ubi->avail_pebs);
246 		err = -ENOSPC;
247 		goto out_unlock;
248 	}
249 	ubi->avail_pebs -= vol->reserved_pebs;
250 	ubi->rsvd_pebs += vol->reserved_pebs;
251 
252 	vol->vol_id    = vol_id;
253 	vol->alignment = req->alignment;
254 	vol->data_pad  = ubi->leb_size % vol->alignment;
255 	vol->vol_type  = req->vol_type;
256 	vol->name_len  = req->name_len;
257 	memcpy(vol->name, req->name, vol->name_len + 1);
258 	vol->exclusive = 1;
259 	vol->ubi = ubi;
260 	ubi->volumes[vol_id] = vol;
261 	spin_unlock(&ubi->volumes_lock);
262 
263 	/*
264 	 * Finish all pending erases because there may be some LEBs belonging
265 	 * to the same volume ID.
266 	 */
267 	err = ubi_wl_flush(ubi);
268 	if (err)
269 		goto out_acc;
270 
271 	vol->eba_tbl = kmalloc(vol->reserved_pebs * sizeof(int), GFP_KERNEL);
272 	if (!vol->eba_tbl) {
273 		err = -ENOMEM;
274 		goto out_acc;
275 	}
276 
277 	for (i = 0; i < vol->reserved_pebs; i++)
278 		vol->eba_tbl[i] = UBI_LEB_UNMAPPED;
279 
280 	if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
281 		vol->used_ebs = vol->reserved_pebs;
282 		vol->last_eb_bytes = vol->usable_leb_size;
283 		vol->used_bytes =
284 			(long long)vol->used_ebs * vol->usable_leb_size;
285 	} else {
286 		bytes = vol->used_bytes;
287 		vol->last_eb_bytes = do_div(bytes, vol->usable_leb_size);
288 		vol->used_ebs = bytes;
289 		if (vol->last_eb_bytes)
290 			vol->used_ebs += 1;
291 		else
292 			vol->last_eb_bytes = vol->usable_leb_size;
293 	}
294 
295 	/* Register character device for the volume */
296 	cdev_init(&vol->cdev, &ubi_vol_cdev_operations);
297 	vol->cdev.owner = THIS_MODULE;
298 	err = cdev_add(&vol->cdev, MKDEV(ubi->major, vol_id + 1), 1);
299 	if (err) {
300 		ubi_err("cannot add character device for volume %d", vol_id);
301 		goto out_mapping;
302 	}
303 
304 	err = ubi_create_gluebi(ubi, vol);
305 	if (err)
306 		goto out_cdev;
307 
308 	vol->dev.release = vol_release;
309 	vol->dev.parent = &ubi->dev;
310 	vol->dev.devt = MKDEV(ubi->major, vol->vol_id + 1);
311 	vol->dev.class = ubi_class;
312 	sprintf(&vol->dev.bus_id[0], "%s_%d", ubi->ubi_name, vol->vol_id);
313 	err = device_register(&vol->dev);
314 	if (err)
315 		goto out_gluebi;
316 
317 	err = volume_sysfs_init(ubi, vol);
318 	if (err)
319 		goto out_sysfs;
320 
321 	/* Fill volume table record */
322 	memset(&vtbl_rec, 0, sizeof(struct ubi_vtbl_record));
323 	vtbl_rec.reserved_pebs = cpu_to_be32(vol->reserved_pebs);
324 	vtbl_rec.alignment     = cpu_to_be32(vol->alignment);
325 	vtbl_rec.data_pad      = cpu_to_be32(vol->data_pad);
326 	vtbl_rec.name_len      = cpu_to_be16(vol->name_len);
327 	if (vol->vol_type == UBI_DYNAMIC_VOLUME)
328 		vtbl_rec.vol_type = UBI_VID_DYNAMIC;
329 	else
330 		vtbl_rec.vol_type = UBI_VID_STATIC;
331 	memcpy(vtbl_rec.name, vol->name, vol->name_len + 1);
332 
333 	err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
334 	if (err)
335 		goto out_sysfs;
336 
337 	spin_lock(&ubi->volumes_lock);
338 	ubi->vol_count += 1;
339 	vol->exclusive = 0;
340 	spin_unlock(&ubi->volumes_lock);
341 
342 	paranoid_check_volumes(ubi);
343 	return 0;
344 
345 out_gluebi:
346 	err = ubi_destroy_gluebi(vol);
347 out_cdev:
348 	cdev_del(&vol->cdev);
349 out_mapping:
350 	kfree(vol->eba_tbl);
351 out_acc:
352 	spin_lock(&ubi->volumes_lock);
353 	ubi->rsvd_pebs -= vol->reserved_pebs;
354 	ubi->avail_pebs += vol->reserved_pebs;
355 	ubi->volumes[vol_id] = NULL;
356 out_unlock:
357 	spin_unlock(&ubi->volumes_lock);
358 	kfree(vol);
359 	return err;
360 
361 	/*
362 	 * We are registered, so @vol is destroyed in the release function and
363 	 * we have to de-initialize differently.
364 	 */
365 out_sysfs:
366 	err = ubi_destroy_gluebi(vol);
367 	cdev_del(&vol->cdev);
368 	kfree(vol->eba_tbl);
369 	spin_lock(&ubi->volumes_lock);
370 	ubi->rsvd_pebs -= vol->reserved_pebs;
371 	ubi->avail_pebs += vol->reserved_pebs;
372 	ubi->volumes[vol_id] = NULL;
373 	spin_unlock(&ubi->volumes_lock);
374 	volume_sysfs_close(vol);
375 	return err;
376 }
377 
378 /**
379  * ubi_remove_volume - remove volume.
380  * @desc: volume descriptor
381  *
382  * This function removes volume described by @desc. The volume has to be opened
383  * in "exclusive" mode. Returns zero in case of success and a negative error
384  * code in case of failure.
385  */
386 int ubi_remove_volume(struct ubi_volume_desc *desc)
387 {
388 	struct ubi_volume *vol = desc->vol;
389 	struct ubi_device *ubi = vol->ubi;
390 	int i, err, vol_id = vol->vol_id, reserved_pebs = vol->reserved_pebs;
391 
392 	dbg_msg("remove UBI volume %d", vol_id);
393 	ubi_assert(desc->mode == UBI_EXCLUSIVE);
394 	ubi_assert(vol == ubi->volumes[vol_id]);
395 
396 	if (ubi->ro_mode)
397 		return -EROFS;
398 
399 	err = ubi_destroy_gluebi(vol);
400 	if (err)
401 		return err;
402 
403 	err = ubi_change_vtbl_record(ubi, vol_id, NULL);
404 	if (err)
405 		return err;
406 
407 	for (i = 0; i < vol->reserved_pebs; i++) {
408 		err = ubi_eba_unmap_leb(ubi, vol_id, i);
409 		if (err)
410 			return err;
411 	}
412 
413 	spin_lock(&ubi->volumes_lock);
414 	vol->removed = 1;
415 	ubi->volumes[vol_id] = NULL;
416 	spin_unlock(&ubi->volumes_lock);
417 
418 	kfree(vol->eba_tbl);
419 	vol->eba_tbl = NULL;
420 	cdev_del(&vol->cdev);
421 	volume_sysfs_close(vol);
422 	kfree(desc);
423 
424 	spin_lock(&ubi->volumes_lock);
425 	ubi->rsvd_pebs -= reserved_pebs;
426 	ubi->avail_pebs += reserved_pebs;
427 	i = ubi->beb_rsvd_level - ubi->beb_rsvd_pebs;
428 	if (i > 0) {
429 		i = ubi->avail_pebs >= i ? i : ubi->avail_pebs;
430 		ubi->avail_pebs -= i;
431 		ubi->rsvd_pebs += i;
432 		ubi->beb_rsvd_pebs += i;
433 		if (i > 0)
434 			ubi_msg("reserve more %d PEBs", i);
435 	}
436 	ubi->vol_count -= 1;
437 	spin_unlock(&ubi->volumes_lock);
438 
439 	paranoid_check_volumes(ubi);
440 	module_put(THIS_MODULE);
441 	return 0;
442 }
443 
444 /**
445  * ubi_resize_volume - re-size volume.
446  * @desc: volume descriptor
447  * @reserved_pebs: new size in physical eraseblocks
448  *
449  * This function returns zero in case of success, and a negative error code in
450  * case of failure.
451  */
452 int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs)
453 {
454 	int i, err, pebs, *new_mapping;
455 	struct ubi_volume *vol = desc->vol;
456 	struct ubi_device *ubi = vol->ubi;
457 	struct ubi_vtbl_record vtbl_rec;
458 	int vol_id = vol->vol_id;
459 
460 	if (ubi->ro_mode)
461 		return -EROFS;
462 
463 	dbg_msg("re-size volume %d to from %d to %d PEBs",
464 		vol_id, vol->reserved_pebs, reserved_pebs);
465 	ubi_assert(desc->mode == UBI_EXCLUSIVE);
466 	ubi_assert(vol == ubi->volumes[vol_id]);
467 
468 	if (vol->vol_type == UBI_STATIC_VOLUME &&
469 	    reserved_pebs < vol->used_ebs) {
470 		dbg_err("too small size %d, %d LEBs contain data",
471 			reserved_pebs, vol->used_ebs);
472 		return -EINVAL;
473 	}
474 
475 	/* If the size is the same, we have nothing to do */
476 	if (reserved_pebs == vol->reserved_pebs)
477 		return 0;
478 
479 	new_mapping = kmalloc(reserved_pebs * sizeof(int), GFP_KERNEL);
480 	if (!new_mapping)
481 		return -ENOMEM;
482 
483 	for (i = 0; i < reserved_pebs; i++)
484 		new_mapping[i] = UBI_LEB_UNMAPPED;
485 
486 	/* Reserve physical eraseblocks */
487 	pebs = reserved_pebs - vol->reserved_pebs;
488 	if (pebs > 0) {
489 		spin_lock(&ubi->volumes_lock);
490 		if (pebs > ubi->avail_pebs) {
491 			dbg_err("not enough PEBs: requested %d, available %d",
492 				pebs, ubi->avail_pebs);
493 			spin_unlock(&ubi->volumes_lock);
494 			err = -ENOSPC;
495 			goto out_free;
496 		}
497 		ubi->avail_pebs -= pebs;
498 		ubi->rsvd_pebs += pebs;
499 		for (i = 0; i < vol->reserved_pebs; i++)
500 			new_mapping[i] = vol->eba_tbl[i];
501 		kfree(vol->eba_tbl);
502 		vol->eba_tbl = new_mapping;
503 		spin_unlock(&ubi->volumes_lock);
504 	}
505 
506 	/* Change volume table record */
507 	memcpy(&vtbl_rec, &ubi->vtbl[vol_id], sizeof(struct ubi_vtbl_record));
508 	vtbl_rec.reserved_pebs = cpu_to_be32(reserved_pebs);
509 	err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
510 	if (err)
511 		goto out_acc;
512 
513 	if (pebs < 0) {
514 		for (i = 0; i < -pebs; i++) {
515 			err = ubi_eba_unmap_leb(ubi, vol_id, reserved_pebs + i);
516 			if (err)
517 				goto out_acc;
518 		}
519 		spin_lock(&ubi->volumes_lock);
520 		ubi->rsvd_pebs += pebs;
521 		ubi->avail_pebs -= pebs;
522 		pebs = ubi->beb_rsvd_level - ubi->beb_rsvd_pebs;
523 		if (pebs > 0) {
524 			pebs = ubi->avail_pebs >= pebs ? pebs : ubi->avail_pebs;
525 			ubi->avail_pebs -= pebs;
526 			ubi->rsvd_pebs += pebs;
527 			ubi->beb_rsvd_pebs += pebs;
528 			if (pebs > 0)
529 				ubi_msg("reserve more %d PEBs", pebs);
530 		}
531 		for (i = 0; i < reserved_pebs; i++)
532 			new_mapping[i] = vol->eba_tbl[i];
533 		kfree(vol->eba_tbl);
534 		vol->eba_tbl = new_mapping;
535 		spin_unlock(&ubi->volumes_lock);
536 	}
537 
538 	vol->reserved_pebs = reserved_pebs;
539 	if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
540 		vol->used_ebs = reserved_pebs;
541 		vol->last_eb_bytes = vol->usable_leb_size;
542 		vol->used_bytes =
543 			(long long)vol->used_ebs * vol->usable_leb_size;
544 	}
545 
546 	paranoid_check_volumes(ubi);
547 	return 0;
548 
549 out_acc:
550 	if (pebs > 0) {
551 		spin_lock(&ubi->volumes_lock);
552 		ubi->rsvd_pebs -= pebs;
553 		ubi->avail_pebs += pebs;
554 		spin_unlock(&ubi->volumes_lock);
555 	}
556 out_free:
557 	kfree(new_mapping);
558 	return err;
559 }
560 
561 /**
562  * ubi_add_volume - add volume.
563  * @ubi: UBI device description object
564  * @vol_id: volume ID
565  *
566  * This function adds an existin volume and initializes all its data
567  * structures. Returnes zero in case of success and a negative error code in
568  * case of failure.
569  */
570 int ubi_add_volume(struct ubi_device *ubi, int vol_id)
571 {
572 	int err;
573 	struct ubi_volume *vol = ubi->volumes[vol_id];
574 
575 	dbg_msg("add volume %d", vol_id);
576 	ubi_dbg_dump_vol_info(vol);
577 	ubi_assert(vol);
578 
579 	/* Register character device for the volume */
580 	cdev_init(&vol->cdev, &ubi_vol_cdev_operations);
581 	vol->cdev.owner = THIS_MODULE;
582 	err = cdev_add(&vol->cdev, MKDEV(ubi->major, vol->vol_id + 1), 1);
583 	if (err) {
584 		ubi_err("cannot add character device for volume %d", vol_id);
585 		return err;
586 	}
587 
588 	err = ubi_create_gluebi(ubi, vol);
589 	if (err)
590 		goto out_cdev;
591 
592 	vol->dev.release = vol_release;
593 	vol->dev.parent = &ubi->dev;
594 	vol->dev.devt = MKDEV(ubi->major, vol->vol_id + 1);
595 	vol->dev.class = ubi_class;
596 	sprintf(&vol->dev.bus_id[0], "%s_%d", ubi->ubi_name, vol->vol_id);
597 	err = device_register(&vol->dev);
598 	if (err)
599 		goto out_gluebi;
600 
601 	err = volume_sysfs_init(ubi, vol);
602 	if (err) {
603 		cdev_del(&vol->cdev);
604 		err = ubi_destroy_gluebi(vol);
605 		volume_sysfs_close(vol);
606 		return err;
607 	}
608 
609 	paranoid_check_volumes(ubi);
610 	return 0;
611 
612 out_gluebi:
613 	err = ubi_destroy_gluebi(vol);
614 out_cdev:
615 	cdev_del(&vol->cdev);
616 	return err;
617 }
618 
619 /**
620  * ubi_free_volume - free volume.
621  * @ubi: UBI device description object
622  * @vol_id: volume ID
623  *
624  * This function frees all resources for volume @vol_id but does not remove it.
625  * Used only when the UBI device is detached.
626  */
627 void ubi_free_volume(struct ubi_device *ubi, int vol_id)
628 {
629 	int err;
630 	struct ubi_volume *vol = ubi->volumes[vol_id];
631 
632 	dbg_msg("free volume %d", vol_id);
633 	ubi_assert(vol);
634 
635 	vol->removed = 1;
636 	err = ubi_destroy_gluebi(vol);
637 	ubi->volumes[vol_id] = NULL;
638 	cdev_del(&vol->cdev);
639 	volume_sysfs_close(vol);
640 }
641 
642 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
643 
644 /**
645  * paranoid_check_volume - check volume information.
646  * @ubi: UBI device description object
647  * @vol_id: volume ID
648  */
649 static void paranoid_check_volume(struct ubi_device *ubi, int vol_id)
650 {
651 	int idx = vol_id2idx(ubi, vol_id);
652 	int reserved_pebs, alignment, data_pad, vol_type, name_len, upd_marker;
653 	const struct ubi_volume *vol;
654 	long long n;
655 	const char *name;
656 
657 	spin_lock(&ubi->volumes_lock);
658 	reserved_pebs = be32_to_cpu(ubi->vtbl[vol_id].reserved_pebs);
659 	vol = ubi->volumes[idx];
660 
661 	if (!vol) {
662 		if (reserved_pebs) {
663 			ubi_err("no volume info, but volume exists");
664 			goto fail;
665 		}
666 		spin_unlock(&ubi->volumes_lock);
667 		return;
668 	}
669 
670 	if (vol->exclusive) {
671 		/*
672 		 * The volume may be being created at the moment, do not check
673 		 * it (e.g., it may be in the middle of ubi_create_volume().
674 		 */
675 		spin_unlock(&ubi->volumes_lock);
676 		return;
677 	}
678 
679 	if (vol->reserved_pebs < 0 || vol->alignment < 0 || vol->data_pad < 0 ||
680 	    vol->name_len < 0) {
681 		ubi_err("negative values");
682 		goto fail;
683 	}
684 	if (vol->alignment > ubi->leb_size || vol->alignment == 0) {
685 		ubi_err("bad alignment");
686 		goto fail;
687 	}
688 
689 	n = vol->alignment % ubi->min_io_size;
690 	if (vol->alignment != 1 && n) {
691 		ubi_err("alignment is not multiple of min I/O unit");
692 		goto fail;
693 	}
694 
695 	n = ubi->leb_size % vol->alignment;
696 	if (vol->data_pad != n) {
697 		ubi_err("bad data_pad, has to be %lld", n);
698 		goto fail;
699 	}
700 
701 	if (vol->vol_type != UBI_DYNAMIC_VOLUME &&
702 	    vol->vol_type != UBI_STATIC_VOLUME) {
703 		ubi_err("bad vol_type");
704 		goto fail;
705 	}
706 
707 	if (vol->upd_marker != 0 && vol->upd_marker != 1) {
708 		ubi_err("bad upd_marker");
709 		goto fail;
710 	}
711 
712 	if (vol->upd_marker && vol->corrupted) {
713 		dbg_err("update marker and corrupted simultaneously");
714 		goto fail;
715 	}
716 
717 	if (vol->reserved_pebs > ubi->good_peb_count) {
718 		ubi_err("too large reserved_pebs");
719 		goto fail;
720 	}
721 
722 	n = ubi->leb_size - vol->data_pad;
723 	if (vol->usable_leb_size != ubi->leb_size - vol->data_pad) {
724 		ubi_err("bad usable_leb_size, has to be %lld", n);
725 		goto fail;
726 	}
727 
728 	if (vol->name_len > UBI_VOL_NAME_MAX) {
729 		ubi_err("too long volume name, max is %d", UBI_VOL_NAME_MAX);
730 		goto fail;
731 	}
732 
733 	if (!vol->name) {
734 		ubi_err("NULL volume name");
735 		goto fail;
736 	}
737 
738 	n = strnlen(vol->name, vol->name_len + 1);
739 	if (n != vol->name_len) {
740 		ubi_err("bad name_len %lld", n);
741 		goto fail;
742 	}
743 
744 	n = (long long)vol->used_ebs * vol->usable_leb_size;
745 	if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
746 		if (vol->corrupted != 0) {
747 			ubi_err("corrupted dynamic volume");
748 			goto fail;
749 		}
750 		if (vol->used_ebs != vol->reserved_pebs) {
751 			ubi_err("bad used_ebs");
752 			goto fail;
753 		}
754 		if (vol->last_eb_bytes != vol->usable_leb_size) {
755 			ubi_err("bad last_eb_bytes");
756 			goto fail;
757 		}
758 		if (vol->used_bytes != n) {
759 			ubi_err("bad used_bytes");
760 			goto fail;
761 		}
762 	} else {
763 		if (vol->corrupted != 0 && vol->corrupted != 1) {
764 			ubi_err("bad corrupted");
765 			goto fail;
766 		}
767 		if (vol->used_ebs < 0 || vol->used_ebs > vol->reserved_pebs) {
768 			ubi_err("bad used_ebs");
769 			goto fail;
770 		}
771 		if (vol->last_eb_bytes < 0 ||
772 		    vol->last_eb_bytes > vol->usable_leb_size) {
773 			ubi_err("bad last_eb_bytes");
774 			goto fail;
775 		}
776 		if (vol->used_bytes < 0 || vol->used_bytes > n ||
777 		    vol->used_bytes < n - vol->usable_leb_size) {
778 			ubi_err("bad used_bytes");
779 			goto fail;
780 		}
781 	}
782 
783 	alignment  = be32_to_cpu(ubi->vtbl[vol_id].alignment);
784 	data_pad   = be32_to_cpu(ubi->vtbl[vol_id].data_pad);
785 	name_len   = be16_to_cpu(ubi->vtbl[vol_id].name_len);
786 	upd_marker = ubi->vtbl[vol_id].upd_marker;
787 	name       = &ubi->vtbl[vol_id].name[0];
788 	if (ubi->vtbl[vol_id].vol_type == UBI_VID_DYNAMIC)
789 		vol_type = UBI_DYNAMIC_VOLUME;
790 	else
791 		vol_type = UBI_STATIC_VOLUME;
792 
793 	if (alignment != vol->alignment || data_pad != vol->data_pad ||
794 	    upd_marker != vol->upd_marker || vol_type != vol->vol_type ||
795 	    name_len!= vol->name_len || strncmp(name, vol->name, name_len)) {
796 		ubi_err("volume info is different");
797 		goto fail;
798 	}
799 
800 	spin_unlock(&ubi->volumes_lock);
801 	return;
802 
803 fail:
804 	ubi_err("paranoid check failed for volume %d", vol_id);
805 	ubi_dbg_dump_vol_info(vol);
806 	ubi_dbg_dump_vtbl_record(&ubi->vtbl[vol_id], vol_id);
807 	spin_unlock(&ubi->volumes_lock);
808 	BUG();
809 }
810 
811 /**
812  * paranoid_check_volumes - check information about all volumes.
813  * @ubi: UBI device description object
814  */
815 static void paranoid_check_volumes(struct ubi_device *ubi)
816 {
817 	int i;
818 
819 	mutex_lock(&ubi->vtbl_mutex);
820 	for (i = 0; i < ubi->vtbl_slots; i++)
821 		paranoid_check_volume(ubi, i);
822 	mutex_unlock(&ubi->vtbl_mutex);
823 }
824 #endif
825