xref: /openbmc/u-boot/drivers/mtd/ubi/vmt.c (revision e246b728)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) International Business Machines Corp., 2006
4  *
5  * Author: Artem Bityutskiy (Битюцкий Артём)
6  */
7 
8 /*
9  * This file contains implementation of volume creation, deletion, updating and
10  * resizing.
11  */
12 
13 #ifndef __UBOOT__
14 #include <linux/err.h>
15 #include <linux/slab.h>
16 #include <linux/export.h>
17 #else
18 #include <div64.h>
19 #include <ubi_uboot.h>
20 #endif
21 #include <linux/math64.h>
22 
23 #include "ubi.h"
24 
25 static int self_check_volumes(struct ubi_device *ubi);
26 
27 #ifndef __UBOOT__
28 static ssize_t vol_attribute_show(struct device *dev,
29 				  struct device_attribute *attr, char *buf);
30 
31 /* Device attributes corresponding to files in '/<sysfs>/class/ubi/ubiX_Y' */
32 static struct device_attribute attr_vol_reserved_ebs =
33 	__ATTR(reserved_ebs, S_IRUGO, vol_attribute_show, NULL);
34 static struct device_attribute attr_vol_type =
35 	__ATTR(type, S_IRUGO, vol_attribute_show, NULL);
36 static struct device_attribute attr_vol_name =
37 	__ATTR(name, S_IRUGO, vol_attribute_show, NULL);
38 static struct device_attribute attr_vol_corrupted =
39 	__ATTR(corrupted, S_IRUGO, vol_attribute_show, NULL);
40 static struct device_attribute attr_vol_alignment =
41 	__ATTR(alignment, S_IRUGO, vol_attribute_show, NULL);
42 static struct device_attribute attr_vol_usable_eb_size =
43 	__ATTR(usable_eb_size, S_IRUGO, vol_attribute_show, NULL);
44 static struct device_attribute attr_vol_data_bytes =
45 	__ATTR(data_bytes, S_IRUGO, vol_attribute_show, NULL);
46 static struct device_attribute attr_vol_upd_marker =
47 	__ATTR(upd_marker, S_IRUGO, vol_attribute_show, NULL);
48 
49 /*
50  * "Show" method for files in '/<sysfs>/class/ubi/ubiX_Y/'.
51  *
52  * Consider a situation:
53  * A. process 1 opens a sysfs file related to volume Y, say
54  *    /<sysfs>/class/ubi/ubiX_Y/reserved_ebs;
55  * B. process 2 removes volume Y;
56  * C. process 1 starts reading the /<sysfs>/class/ubi/ubiX_Y/reserved_ebs file;
57  *
58  * In this situation, this function will return %-ENODEV because it will find
59  * out that the volume was removed from the @ubi->volumes array.
60  */
61 static ssize_t vol_attribute_show(struct device *dev,
62 				  struct device_attribute *attr, char *buf)
63 {
64 	int ret;
65 	struct ubi_volume *vol = container_of(dev, struct ubi_volume, dev);
66 	struct ubi_device *ubi;
67 
68 	ubi = ubi_get_device(vol->ubi->ubi_num);
69 	if (!ubi)
70 		return -ENODEV;
71 
72 	spin_lock(&ubi->volumes_lock);
73 	if (!ubi->volumes[vol->vol_id]) {
74 		spin_unlock(&ubi->volumes_lock);
75 		ubi_put_device(ubi);
76 		return -ENODEV;
77 	}
78 	/* Take a reference to prevent volume removal */
79 	vol->ref_count += 1;
80 	spin_unlock(&ubi->volumes_lock);
81 
82 	if (attr == &attr_vol_reserved_ebs)
83 		ret = sprintf(buf, "%d\n", vol->reserved_pebs);
84 	else if (attr == &attr_vol_type) {
85 		const char *tp;
86 
87 		if (vol->vol_type == UBI_DYNAMIC_VOLUME)
88 			tp = "dynamic";
89 		else
90 			tp = "static";
91 		ret = sprintf(buf, "%s\n", tp);
92 	} else if (attr == &attr_vol_name)
93 		ret = sprintf(buf, "%s\n", vol->name);
94 	else if (attr == &attr_vol_corrupted)
95 		ret = sprintf(buf, "%d\n", vol->corrupted);
96 	else if (attr == &attr_vol_alignment)
97 		ret = sprintf(buf, "%d\n", vol->alignment);
98 	else if (attr == &attr_vol_usable_eb_size)
99 		ret = sprintf(buf, "%d\n", vol->usable_leb_size);
100 	else if (attr == &attr_vol_data_bytes)
101 		ret = sprintf(buf, "%lld\n", vol->used_bytes);
102 	else if (attr == &attr_vol_upd_marker)
103 		ret = sprintf(buf, "%d\n", vol->upd_marker);
104 	else
105 		/* This must be a bug */
106 		ret = -EINVAL;
107 
108 	/* We've done the operation, drop volume and UBI device references */
109 	spin_lock(&ubi->volumes_lock);
110 	vol->ref_count -= 1;
111 	ubi_assert(vol->ref_count >= 0);
112 	spin_unlock(&ubi->volumes_lock);
113 	ubi_put_device(ubi);
114 	return ret;
115 }
116 
117 static struct attribute *volume_dev_attrs[] = {
118 	&attr_vol_reserved_ebs.attr,
119 	&attr_vol_type.attr,
120 	&attr_vol_name.attr,
121 	&attr_vol_corrupted.attr,
122 	&attr_vol_alignment.attr,
123 	&attr_vol_usable_eb_size.attr,
124 	&attr_vol_data_bytes.attr,
125 	&attr_vol_upd_marker.attr,
126 	NULL
127 };
128 ATTRIBUTE_GROUPS(volume_dev);
129 #endif
130 
131 /* Release method for volume devices */
132 static void vol_release(struct device *dev)
133 {
134 	struct ubi_volume *vol = container_of(dev, struct ubi_volume, dev);
135 
136 	kfree(vol->eba_tbl);
137 	kfree(vol);
138 }
139 
140 /**
141  * ubi_create_volume - create volume.
142  * @ubi: UBI device description object
143  * @req: volume creation request
144  *
145  * This function creates volume described by @req. If @req->vol_id id
146  * %UBI_VOL_NUM_AUTO, this function automatically assign ID to the new volume
147  * and saves it in @req->vol_id. Returns zero in case of success and a negative
148  * error code in case of failure. Note, the caller has to have the
149  * @ubi->device_mutex locked.
150  */
151 int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req)
152 {
153 	int i, err, vol_id = req->vol_id, do_free = 1;
154 	struct ubi_volume *vol;
155 	struct ubi_vtbl_record vtbl_rec;
156 	dev_t dev;
157 
158 	if (ubi->ro_mode)
159 		return -EROFS;
160 
161 	vol = kzalloc(sizeof(struct ubi_volume), GFP_KERNEL);
162 	if (!vol)
163 		return -ENOMEM;
164 
165 	spin_lock(&ubi->volumes_lock);
166 	if (vol_id == UBI_VOL_NUM_AUTO) {
167 		/* Find unused volume ID */
168 		dbg_gen("search for vacant volume ID");
169 		for (i = 0; i < ubi->vtbl_slots; i++)
170 			if (!ubi->volumes[i]) {
171 				vol_id = i;
172 				break;
173 			}
174 
175 		if (vol_id == UBI_VOL_NUM_AUTO) {
176 			ubi_err(ubi, "out of volume IDs");
177 			err = -ENFILE;
178 			goto out_unlock;
179 		}
180 		req->vol_id = vol_id;
181 	}
182 
183 	dbg_gen("create device %d, volume %d, %llu bytes, type %d, name %s",
184 		ubi->ubi_num, vol_id, (unsigned long long)req->bytes,
185 		(int)req->vol_type, req->name);
186 
187 	/* Ensure that this volume does not exist */
188 	err = -EEXIST;
189 	if (ubi->volumes[vol_id]) {
190 		ubi_err(ubi, "volume %d already exists", vol_id);
191 		goto out_unlock;
192 	}
193 
194 	/* Ensure that the name is unique */
195 	for (i = 0; i < ubi->vtbl_slots; i++)
196 		if (ubi->volumes[i] &&
197 		    ubi->volumes[i]->name_len == req->name_len &&
198 		    !strcmp(ubi->volumes[i]->name, req->name)) {
199 			ubi_err(ubi, "volume \"%s\" exists (ID %d)",
200 				req->name, i);
201 			goto out_unlock;
202 		}
203 
204 	/* Calculate how many eraseblocks are requested */
205 	vol->usable_leb_size = ubi->leb_size - ubi->leb_size % req->alignment;
206 	vol->reserved_pebs = div_u64(req->bytes + vol->usable_leb_size - 1,
207 				     vol->usable_leb_size);
208 
209 	/* Reserve physical eraseblocks */
210 	if (vol->reserved_pebs > ubi->avail_pebs) {
211 		ubi_err(ubi, "not enough PEBs, only %d available",
212 			ubi->avail_pebs);
213 		if (ubi->corr_peb_count)
214 			ubi_err(ubi, "%d PEBs are corrupted and not used",
215 				ubi->corr_peb_count);
216 		err = -ENOSPC;
217 		goto out_unlock;
218 	}
219 	ubi->avail_pebs -= vol->reserved_pebs;
220 	ubi->rsvd_pebs += vol->reserved_pebs;
221 	spin_unlock(&ubi->volumes_lock);
222 
223 	vol->vol_id    = vol_id;
224 	vol->alignment = req->alignment;
225 	vol->data_pad  = ubi->leb_size % vol->alignment;
226 	vol->vol_type  = req->vol_type;
227 	vol->name_len  = req->name_len;
228 	memcpy(vol->name, req->name, vol->name_len);
229 	vol->ubi = ubi;
230 
231 	/*
232 	 * Finish all pending erases because there may be some LEBs belonging
233 	 * to the same volume ID.
234 	 */
235 	err = ubi_wl_flush(ubi, vol_id, UBI_ALL);
236 	if (err)
237 		goto out_acc;
238 
239 	vol->eba_tbl = kmalloc(vol->reserved_pebs * sizeof(int), GFP_KERNEL);
240 	if (!vol->eba_tbl) {
241 		err = -ENOMEM;
242 		goto out_acc;
243 	}
244 
245 	for (i = 0; i < vol->reserved_pebs; i++)
246 		vol->eba_tbl[i] = UBI_LEB_UNMAPPED;
247 
248 	if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
249 		vol->used_ebs = vol->reserved_pebs;
250 		vol->last_eb_bytes = vol->usable_leb_size;
251 		vol->used_bytes =
252 			(long long)vol->used_ebs * vol->usable_leb_size;
253 	} else {
254 		vol->used_ebs = div_u64_rem(vol->used_bytes,
255 					    vol->usable_leb_size,
256 					    &vol->last_eb_bytes);
257 		if (vol->last_eb_bytes != 0)
258 			vol->used_ebs += 1;
259 		else
260 			vol->last_eb_bytes = vol->usable_leb_size;
261 	}
262 
263 	/* Register character device for the volume */
264 	cdev_init(&vol->cdev, &ubi_vol_cdev_operations);
265 	vol->cdev.owner = THIS_MODULE;
266 	dev = MKDEV(MAJOR(ubi->cdev.dev), vol_id + 1);
267 	err = cdev_add(&vol->cdev, dev, 1);
268 	if (err) {
269 		ubi_err(ubi, "cannot add character device");
270 		goto out_mapping;
271 	}
272 
273 	vol->dev.release = vol_release;
274 	vol->dev.parent = &ubi->dev;
275 	vol->dev.devt = dev;
276 #ifndef __UBOOT__
277 	vol->dev.class = &ubi_class;
278 	vol->dev.groups = volume_dev_groups;
279 #endif
280 
281 	dev_set_name(&vol->dev, "%s_%d", ubi->ubi_name, vol->vol_id);
282 	err = device_register(&vol->dev);
283 	if (err) {
284 		ubi_err(ubi, "cannot register device");
285 		goto out_cdev;
286 	}
287 
288 	/* Fill volume table record */
289 	memset(&vtbl_rec, 0, sizeof(struct ubi_vtbl_record));
290 	vtbl_rec.reserved_pebs = cpu_to_be32(vol->reserved_pebs);
291 	vtbl_rec.alignment     = cpu_to_be32(vol->alignment);
292 	vtbl_rec.data_pad      = cpu_to_be32(vol->data_pad);
293 	vtbl_rec.name_len      = cpu_to_be16(vol->name_len);
294 	if (vol->vol_type == UBI_DYNAMIC_VOLUME)
295 		vtbl_rec.vol_type = UBI_VID_DYNAMIC;
296 	else
297 		vtbl_rec.vol_type = UBI_VID_STATIC;
298 	memcpy(vtbl_rec.name, vol->name, vol->name_len);
299 
300 	err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
301 	if (err)
302 		goto out_sysfs;
303 
304 	spin_lock(&ubi->volumes_lock);
305 	ubi->volumes[vol_id] = vol;
306 	ubi->vol_count += 1;
307 	spin_unlock(&ubi->volumes_lock);
308 
309 	ubi_volume_notify(ubi, vol, UBI_VOLUME_ADDED);
310 	self_check_volumes(ubi);
311 	return err;
312 
313 out_sysfs:
314 	/*
315 	 * We have registered our device, we should not free the volume
316 	 * description object in this function in case of an error - it is
317 	 * freed by the release function.
318 	 *
319 	 * Get device reference to prevent the release function from being
320 	 * called just after sysfs has been closed.
321 	 */
322 	do_free = 0;
323 	get_device(&vol->dev);
324 	device_unregister(&vol->dev);
325 out_cdev:
326 	cdev_del(&vol->cdev);
327 out_mapping:
328 	if (do_free)
329 		kfree(vol->eba_tbl);
330 out_acc:
331 	spin_lock(&ubi->volumes_lock);
332 	ubi->rsvd_pebs -= vol->reserved_pebs;
333 	ubi->avail_pebs += vol->reserved_pebs;
334 out_unlock:
335 	spin_unlock(&ubi->volumes_lock);
336 	if (do_free)
337 		kfree(vol);
338 	else
339 		put_device(&vol->dev);
340 	ubi_err(ubi, "cannot create volume %d, error %d", vol_id, err);
341 	return err;
342 }
343 
344 /**
345  * ubi_remove_volume - remove volume.
346  * @desc: volume descriptor
347  * @no_vtbl: do not change volume table if not zero
348  *
349  * This function removes volume described by @desc. The volume has to be opened
350  * in "exclusive" mode. Returns zero in case of success and a negative error
351  * code in case of failure. The caller has to have the @ubi->device_mutex
352  * locked.
353  */
354 int ubi_remove_volume(struct ubi_volume_desc *desc, int no_vtbl)
355 {
356 	struct ubi_volume *vol = desc->vol;
357 	struct ubi_device *ubi = vol->ubi;
358 	int i, err, vol_id = vol->vol_id, reserved_pebs = vol->reserved_pebs;
359 
360 	dbg_gen("remove device %d, volume %d", ubi->ubi_num, vol_id);
361 	ubi_assert(desc->mode == UBI_EXCLUSIVE);
362 	ubi_assert(vol == ubi->volumes[vol_id]);
363 
364 	if (ubi->ro_mode)
365 		return -EROFS;
366 
367 	spin_lock(&ubi->volumes_lock);
368 	if (vol->ref_count > 1) {
369 		/*
370 		 * The volume is busy, probably someone is reading one of its
371 		 * sysfs files.
372 		 */
373 		err = -EBUSY;
374 		goto out_unlock;
375 	}
376 	ubi->volumes[vol_id] = NULL;
377 	spin_unlock(&ubi->volumes_lock);
378 
379 	if (!no_vtbl) {
380 		err = ubi_change_vtbl_record(ubi, vol_id, NULL);
381 		if (err)
382 			goto out_err;
383 	}
384 
385 	for (i = 0; i < vol->reserved_pebs; i++) {
386 		err = ubi_eba_unmap_leb(ubi, vol, i);
387 		if (err)
388 			goto out_err;
389 	}
390 
391 	cdev_del(&vol->cdev);
392 	device_unregister(&vol->dev);
393 
394 	spin_lock(&ubi->volumes_lock);
395 	ubi->rsvd_pebs -= reserved_pebs;
396 	ubi->avail_pebs += reserved_pebs;
397 	ubi_update_reserved(ubi);
398 	ubi->vol_count -= 1;
399 	spin_unlock(&ubi->volumes_lock);
400 
401 	ubi_volume_notify(ubi, vol, UBI_VOLUME_REMOVED);
402 	if (!no_vtbl)
403 		self_check_volumes(ubi);
404 
405 	return err;
406 
407 out_err:
408 	ubi_err(ubi, "cannot remove volume %d, error %d", vol_id, err);
409 	spin_lock(&ubi->volumes_lock);
410 	ubi->volumes[vol_id] = vol;
411 out_unlock:
412 	spin_unlock(&ubi->volumes_lock);
413 	return err;
414 }
415 
416 /**
417  * ubi_resize_volume - re-size volume.
418  * @desc: volume descriptor
419  * @reserved_pebs: new size in physical eraseblocks
420  *
421  * This function re-sizes the volume and returns zero in case of success, and a
422  * negative error code in case of failure. The caller has to have the
423  * @ubi->device_mutex locked.
424  */
425 int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs)
426 {
427 	int i, err, pebs, *new_mapping;
428 	struct ubi_volume *vol = desc->vol;
429 	struct ubi_device *ubi = vol->ubi;
430 	struct ubi_vtbl_record vtbl_rec;
431 	int vol_id = vol->vol_id;
432 
433 	if (ubi->ro_mode)
434 		return -EROFS;
435 
436 	dbg_gen("re-size device %d, volume %d to from %d to %d PEBs",
437 		ubi->ubi_num, vol_id, vol->reserved_pebs, reserved_pebs);
438 
439 	if (vol->vol_type == UBI_STATIC_VOLUME &&
440 	    reserved_pebs < vol->used_ebs) {
441 		ubi_err(ubi, "too small size %d, %d LEBs contain data",
442 			reserved_pebs, vol->used_ebs);
443 		return -EINVAL;
444 	}
445 
446 	/* If the size is the same, we have nothing to do */
447 	if (reserved_pebs == vol->reserved_pebs)
448 		return 0;
449 
450 	new_mapping = kmalloc(reserved_pebs * sizeof(int), GFP_KERNEL);
451 	if (!new_mapping)
452 		return -ENOMEM;
453 
454 	for (i = 0; i < reserved_pebs; i++)
455 		new_mapping[i] = UBI_LEB_UNMAPPED;
456 
457 	spin_lock(&ubi->volumes_lock);
458 	if (vol->ref_count > 1) {
459 		spin_unlock(&ubi->volumes_lock);
460 		err = -EBUSY;
461 		goto out_free;
462 	}
463 	spin_unlock(&ubi->volumes_lock);
464 
465 	/* Reserve physical eraseblocks */
466 	pebs = reserved_pebs - vol->reserved_pebs;
467 	if (pebs > 0) {
468 		spin_lock(&ubi->volumes_lock);
469 		if (pebs > ubi->avail_pebs) {
470 			ubi_err(ubi, "not enough PEBs: requested %d, available %d",
471 				pebs, ubi->avail_pebs);
472 			if (ubi->corr_peb_count)
473 				ubi_err(ubi, "%d PEBs are corrupted and not used",
474 					ubi->corr_peb_count);
475 			spin_unlock(&ubi->volumes_lock);
476 			err = -ENOSPC;
477 			goto out_free;
478 		}
479 		ubi->avail_pebs -= pebs;
480 		ubi->rsvd_pebs += pebs;
481 		for (i = 0; i < vol->reserved_pebs; i++)
482 			new_mapping[i] = vol->eba_tbl[i];
483 		kfree(vol->eba_tbl);
484 		vol->eba_tbl = new_mapping;
485 		spin_unlock(&ubi->volumes_lock);
486 	}
487 
488 	/* Change volume table record */
489 	vtbl_rec = ubi->vtbl[vol_id];
490 	vtbl_rec.reserved_pebs = cpu_to_be32(reserved_pebs);
491 	err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
492 	if (err)
493 		goto out_acc;
494 
495 	if (pebs < 0) {
496 		for (i = 0; i < -pebs; i++) {
497 			err = ubi_eba_unmap_leb(ubi, vol, reserved_pebs + i);
498 			if (err)
499 				goto out_acc;
500 		}
501 		spin_lock(&ubi->volumes_lock);
502 		ubi->rsvd_pebs += pebs;
503 		ubi->avail_pebs -= pebs;
504 		ubi_update_reserved(ubi);
505 		for (i = 0; i < reserved_pebs; i++)
506 			new_mapping[i] = vol->eba_tbl[i];
507 		kfree(vol->eba_tbl);
508 		vol->eba_tbl = new_mapping;
509 		spin_unlock(&ubi->volumes_lock);
510 	}
511 
512 	vol->reserved_pebs = reserved_pebs;
513 	if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
514 		vol->used_ebs = reserved_pebs;
515 		vol->last_eb_bytes = vol->usable_leb_size;
516 		vol->used_bytes =
517 			(long long)vol->used_ebs * vol->usable_leb_size;
518 	}
519 
520 	ubi_volume_notify(ubi, vol, UBI_VOLUME_RESIZED);
521 	self_check_volumes(ubi);
522 	return err;
523 
524 out_acc:
525 	if (pebs > 0) {
526 		spin_lock(&ubi->volumes_lock);
527 		ubi->rsvd_pebs -= pebs;
528 		ubi->avail_pebs += pebs;
529 		spin_unlock(&ubi->volumes_lock);
530 	}
531 out_free:
532 	kfree(new_mapping);
533 	return err;
534 }
535 
536 /**
537  * ubi_rename_volumes - re-name UBI volumes.
538  * @ubi: UBI device description object
539  * @rename_list: list of &struct ubi_rename_entry objects
540  *
541  * This function re-names or removes volumes specified in the re-name list.
542  * Returns zero in case of success and a negative error code in case of
543  * failure.
544  */
545 int ubi_rename_volumes(struct ubi_device *ubi, struct list_head *rename_list)
546 {
547 	int err;
548 	struct ubi_rename_entry *re;
549 
550 	err = ubi_vtbl_rename_volumes(ubi, rename_list);
551 	if (err)
552 		return err;
553 
554 	list_for_each_entry(re, rename_list, list) {
555 		if (re->remove) {
556 			err = ubi_remove_volume(re->desc, 1);
557 			if (err)
558 				break;
559 		} else {
560 			struct ubi_volume *vol = re->desc->vol;
561 
562 			spin_lock(&ubi->volumes_lock);
563 			vol->name_len = re->new_name_len;
564 			memcpy(vol->name, re->new_name, re->new_name_len + 1);
565 			spin_unlock(&ubi->volumes_lock);
566 			ubi_volume_notify(ubi, vol, UBI_VOLUME_RENAMED);
567 		}
568 	}
569 
570 	if (!err)
571 		self_check_volumes(ubi);
572 	return err;
573 }
574 
575 /**
576  * ubi_add_volume - add volume.
577  * @ubi: UBI device description object
578  * @vol: volume description object
579  *
580  * This function adds an existing volume and initializes all its data
581  * structures. Returns zero in case of success and a negative error code in
582  * case of failure.
583  */
584 int ubi_add_volume(struct ubi_device *ubi, struct ubi_volume *vol)
585 {
586 	int err, vol_id = vol->vol_id;
587 	dev_t dev;
588 
589 	dbg_gen("add volume %d", vol_id);
590 
591 	/* Register character device for the volume */
592 	cdev_init(&vol->cdev, &ubi_vol_cdev_operations);
593 	vol->cdev.owner = THIS_MODULE;
594 	dev = MKDEV(MAJOR(ubi->cdev.dev), vol->vol_id + 1);
595 	err = cdev_add(&vol->cdev, dev, 1);
596 	if (err) {
597 		ubi_err(ubi, "cannot add character device for volume %d, error %d",
598 			vol_id, err);
599 		return err;
600 	}
601 
602 	vol->dev.release = vol_release;
603 	vol->dev.parent = &ubi->dev;
604 	vol->dev.devt = dev;
605 #ifndef __UBOOT__
606 	vol->dev.class = &ubi_class;
607 	vol->dev.groups = volume_dev_groups;
608 #endif
609 	dev_set_name(&vol->dev, "%s_%d", ubi->ubi_name, vol->vol_id);
610 	err = device_register(&vol->dev);
611 	if (err)
612 		goto out_cdev;
613 
614 	self_check_volumes(ubi);
615 	return err;
616 
617 out_cdev:
618 	cdev_del(&vol->cdev);
619 	return err;
620 }
621 
622 /**
623  * ubi_free_volume - free volume.
624  * @ubi: UBI device description object
625  * @vol: volume description object
626  *
627  * This function frees all resources for volume @vol but does not remove it.
628  * Used only when the UBI device is detached.
629  */
630 void ubi_free_volume(struct ubi_device *ubi, struct ubi_volume *vol)
631 {
632 	dbg_gen("free volume %d", vol->vol_id);
633 
634 	ubi->volumes[vol->vol_id] = NULL;
635 	cdev_del(&vol->cdev);
636 	device_unregister(&vol->dev);
637 }
638 
639 /**
640  * self_check_volume - check volume information.
641  * @ubi: UBI device description object
642  * @vol_id: volume ID
643  *
644  * Returns zero if volume is all right and a a negative error code if not.
645  */
646 static int self_check_volume(struct ubi_device *ubi, int vol_id)
647 {
648 	int idx = vol_id2idx(ubi, vol_id);
649 	int reserved_pebs, alignment, data_pad, vol_type, name_len, upd_marker;
650 	const struct ubi_volume *vol;
651 	long long n;
652 	const char *name;
653 
654 	spin_lock(&ubi->volumes_lock);
655 	reserved_pebs = be32_to_cpu(ubi->vtbl[vol_id].reserved_pebs);
656 	vol = ubi->volumes[idx];
657 
658 	if (!vol) {
659 		if (reserved_pebs) {
660 			ubi_err(ubi, "no volume info, but volume exists");
661 			goto fail;
662 		}
663 		spin_unlock(&ubi->volumes_lock);
664 		return 0;
665 	}
666 
667 	if (vol->reserved_pebs < 0 || vol->alignment < 0 || vol->data_pad < 0 ||
668 	    vol->name_len < 0) {
669 		ubi_err(ubi, "negative values");
670 		goto fail;
671 	}
672 	if (vol->alignment > ubi->leb_size || vol->alignment == 0) {
673 		ubi_err(ubi, "bad alignment");
674 		goto fail;
675 	}
676 
677 	n = vol->alignment & (ubi->min_io_size - 1);
678 	if (vol->alignment != 1 && n) {
679 		ubi_err(ubi, "alignment is not multiple of min I/O unit");
680 		goto fail;
681 	}
682 
683 	n = ubi->leb_size % vol->alignment;
684 	if (vol->data_pad != n) {
685 		ubi_err(ubi, "bad data_pad, has to be %lld", n);
686 		goto fail;
687 	}
688 
689 	if (vol->vol_type != UBI_DYNAMIC_VOLUME &&
690 	    vol->vol_type != UBI_STATIC_VOLUME) {
691 		ubi_err(ubi, "bad vol_type");
692 		goto fail;
693 	}
694 
695 	if (vol->upd_marker && vol->corrupted) {
696 		ubi_err(ubi, "update marker and corrupted simultaneously");
697 		goto fail;
698 	}
699 
700 	if (vol->reserved_pebs > ubi->good_peb_count) {
701 		ubi_err(ubi, "too large reserved_pebs");
702 		goto fail;
703 	}
704 
705 	n = ubi->leb_size - vol->data_pad;
706 	if (vol->usable_leb_size != ubi->leb_size - vol->data_pad) {
707 		ubi_err(ubi, "bad usable_leb_size, has to be %lld", n);
708 		goto fail;
709 	}
710 
711 	if (vol->name_len > UBI_VOL_NAME_MAX) {
712 		ubi_err(ubi, "too long volume name, max is %d",
713 			UBI_VOL_NAME_MAX);
714 		goto fail;
715 	}
716 
717 	n = strnlen(vol->name, vol->name_len + 1);
718 	if (n != vol->name_len) {
719 		ubi_err(ubi, "bad name_len %lld", n);
720 		goto fail;
721 	}
722 
723 	n = (long long)vol->used_ebs * vol->usable_leb_size;
724 	if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
725 		if (vol->corrupted) {
726 			ubi_err(ubi, "corrupted dynamic volume");
727 			goto fail;
728 		}
729 		if (vol->used_ebs != vol->reserved_pebs) {
730 			ubi_err(ubi, "bad used_ebs");
731 			goto fail;
732 		}
733 		if (vol->last_eb_bytes != vol->usable_leb_size) {
734 			ubi_err(ubi, "bad last_eb_bytes");
735 			goto fail;
736 		}
737 		if (vol->used_bytes != n) {
738 			ubi_err(ubi, "bad used_bytes");
739 			goto fail;
740 		}
741 	} else {
742 		if (vol->used_ebs < 0 || vol->used_ebs > vol->reserved_pebs) {
743 			ubi_err(ubi, "bad used_ebs");
744 			goto fail;
745 		}
746 		if (vol->last_eb_bytes < 0 ||
747 		    vol->last_eb_bytes > vol->usable_leb_size) {
748 			ubi_err(ubi, "bad last_eb_bytes");
749 			goto fail;
750 		}
751 		if (vol->used_bytes < 0 || vol->used_bytes > n ||
752 		    vol->used_bytes < n - vol->usable_leb_size) {
753 			ubi_err(ubi, "bad used_bytes");
754 			goto fail;
755 		}
756 	}
757 
758 	alignment  = be32_to_cpu(ubi->vtbl[vol_id].alignment);
759 	data_pad   = be32_to_cpu(ubi->vtbl[vol_id].data_pad);
760 	name_len   = be16_to_cpu(ubi->vtbl[vol_id].name_len);
761 	upd_marker = ubi->vtbl[vol_id].upd_marker;
762 	name       = &ubi->vtbl[vol_id].name[0];
763 	if (ubi->vtbl[vol_id].vol_type == UBI_VID_DYNAMIC)
764 		vol_type = UBI_DYNAMIC_VOLUME;
765 	else
766 		vol_type = UBI_STATIC_VOLUME;
767 
768 	if (alignment != vol->alignment || data_pad != vol->data_pad ||
769 	    upd_marker != vol->upd_marker || vol_type != vol->vol_type ||
770 	    name_len != vol->name_len || strncmp(name, vol->name, name_len)) {
771 		ubi_err(ubi, "volume info is different");
772 		goto fail;
773 	}
774 
775 	spin_unlock(&ubi->volumes_lock);
776 	return 0;
777 
778 fail:
779 	ubi_err(ubi, "self-check failed for volume %d", vol_id);
780 	if (vol)
781 		ubi_dump_vol_info(vol);
782 	ubi_dump_vtbl_record(&ubi->vtbl[vol_id], vol_id);
783 	dump_stack();
784 	spin_unlock(&ubi->volumes_lock);
785 	return -EINVAL;
786 }
787 
788 /**
789  * self_check_volumes - check information about all volumes.
790  * @ubi: UBI device description object
791  *
792  * Returns zero if volumes are all right and a a negative error code if not.
793  */
794 static int self_check_volumes(struct ubi_device *ubi)
795 {
796 	int i, err = 0;
797 
798 	if (!ubi_dbg_chk_gen(ubi))
799 		return 0;
800 
801 	for (i = 0; i < ubi->vtbl_slots; i++) {
802 		err = self_check_volume(ubi, i);
803 		if (err)
804 			break;
805 	}
806 
807 	return err;
808 }
809