xref: /kernel/linux/linux-6.6/drivers/mtd/ubi/vmt.c (revision 62306a36)
1// SPDX-License-Identifier: GPL-2.0-or-later
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#include <linux/err.h>
14#include <linux/math64.h>
15#include <linux/slab.h>
16#include <linux/export.h>
17#include "ubi.h"
18
19static int self_check_volumes(struct ubi_device *ubi);
20
21static ssize_t vol_attribute_show(struct device *dev,
22				  struct device_attribute *attr, char *buf);
23
24/* Device attributes corresponding to files in '/<sysfs>/class/ubi/ubiX_Y' */
25static struct device_attribute attr_vol_reserved_ebs =
26	__ATTR(reserved_ebs, S_IRUGO, vol_attribute_show, NULL);
27static struct device_attribute attr_vol_type =
28	__ATTR(type, S_IRUGO, vol_attribute_show, NULL);
29static struct device_attribute attr_vol_name =
30	__ATTR(name, S_IRUGO, vol_attribute_show, NULL);
31static struct device_attribute attr_vol_corrupted =
32	__ATTR(corrupted, S_IRUGO, vol_attribute_show, NULL);
33static struct device_attribute attr_vol_alignment =
34	__ATTR(alignment, S_IRUGO, vol_attribute_show, NULL);
35static struct device_attribute attr_vol_usable_eb_size =
36	__ATTR(usable_eb_size, S_IRUGO, vol_attribute_show, NULL);
37static struct device_attribute attr_vol_data_bytes =
38	__ATTR(data_bytes, S_IRUGO, vol_attribute_show, NULL);
39static struct device_attribute attr_vol_upd_marker =
40	__ATTR(upd_marker, S_IRUGO, vol_attribute_show, NULL);
41
42/*
43 * "Show" method for files in '/<sysfs>/class/ubi/ubiX_Y/'.
44 *
45 * Consider a situation:
46 * A. process 1 opens a sysfs file related to volume Y, say
47 *    /<sysfs>/class/ubi/ubiX_Y/reserved_ebs;
48 * B. process 2 removes volume Y;
49 * C. process 1 starts reading the /<sysfs>/class/ubi/ubiX_Y/reserved_ebs file;
50 *
51 * In this situation, this function will return %-ENODEV because it will find
52 * out that the volume was removed from the @ubi->volumes array.
53 */
54static ssize_t vol_attribute_show(struct device *dev,
55				  struct device_attribute *attr, char *buf)
56{
57	int ret;
58	struct ubi_volume *vol = container_of(dev, struct ubi_volume, dev);
59	struct ubi_device *ubi = vol->ubi;
60
61	spin_lock(&ubi->volumes_lock);
62	if (!ubi->volumes[vol->vol_id]) {
63		spin_unlock(&ubi->volumes_lock);
64		return -ENODEV;
65	}
66	/* Take a reference to prevent volume removal */
67	vol->ref_count += 1;
68	spin_unlock(&ubi->volumes_lock);
69
70	if (attr == &attr_vol_reserved_ebs)
71		ret = sprintf(buf, "%d\n", vol->reserved_pebs);
72	else if (attr == &attr_vol_type) {
73		const char *tp;
74
75		if (vol->vol_type == UBI_DYNAMIC_VOLUME)
76			tp = "dynamic";
77		else
78			tp = "static";
79		ret = sprintf(buf, "%s\n", tp);
80	} else if (attr == &attr_vol_name)
81		ret = sprintf(buf, "%s\n", vol->name);
82	else if (attr == &attr_vol_corrupted)
83		ret = sprintf(buf, "%d\n", vol->corrupted);
84	else if (attr == &attr_vol_alignment)
85		ret = sprintf(buf, "%d\n", vol->alignment);
86	else if (attr == &attr_vol_usable_eb_size)
87		ret = sprintf(buf, "%d\n", vol->usable_leb_size);
88	else if (attr == &attr_vol_data_bytes)
89		ret = sprintf(buf, "%lld\n", vol->used_bytes);
90	else if (attr == &attr_vol_upd_marker)
91		ret = sprintf(buf, "%d\n", vol->upd_marker);
92	else
93		/* This must be a bug */
94		ret = -EINVAL;
95
96	/* We've done the operation, drop volume and UBI device references */
97	spin_lock(&ubi->volumes_lock);
98	vol->ref_count -= 1;
99	ubi_assert(vol->ref_count >= 0);
100	spin_unlock(&ubi->volumes_lock);
101	return ret;
102}
103
104static struct attribute *volume_dev_attrs[] = {
105	&attr_vol_reserved_ebs.attr,
106	&attr_vol_type.attr,
107	&attr_vol_name.attr,
108	&attr_vol_corrupted.attr,
109	&attr_vol_alignment.attr,
110	&attr_vol_usable_eb_size.attr,
111	&attr_vol_data_bytes.attr,
112	&attr_vol_upd_marker.attr,
113	NULL
114};
115ATTRIBUTE_GROUPS(volume_dev);
116
117/* Release method for volume devices */
118static void vol_release(struct device *dev)
119{
120	struct ubi_volume *vol = container_of(dev, struct ubi_volume, dev);
121
122	ubi_eba_replace_table(vol, NULL);
123	ubi_fastmap_destroy_checkmap(vol);
124	kfree(vol);
125}
126
127/**
128 * ubi_create_volume - create volume.
129 * @ubi: UBI device description object
130 * @req: volume creation request
131 *
132 * This function creates volume described by @req. If @req->vol_id id
133 * %UBI_VOL_NUM_AUTO, this function automatically assign ID to the new volume
134 * and saves it in @req->vol_id. Returns zero in case of success and a negative
135 * error code in case of failure. Note, the caller has to have the
136 * @ubi->device_mutex locked.
137 */
138int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req)
139{
140	int i, err, vol_id = req->vol_id;
141	struct ubi_volume *vol;
142	struct ubi_vtbl_record vtbl_rec;
143	struct ubi_eba_table *eba_tbl = NULL;
144
145	if (ubi->ro_mode)
146		return -EROFS;
147
148	vol = kzalloc(sizeof(struct ubi_volume), GFP_KERNEL);
149	if (!vol)
150		return -ENOMEM;
151
152	device_initialize(&vol->dev);
153	vol->dev.release = vol_release;
154	vol->dev.parent = &ubi->dev;
155	vol->dev.class = &ubi_class;
156	vol->dev.groups = volume_dev_groups;
157
158	if (req->flags & UBI_VOL_SKIP_CRC_CHECK_FLG)
159		vol->skip_check = 1;
160
161	spin_lock(&ubi->volumes_lock);
162	if (vol_id == UBI_VOL_NUM_AUTO) {
163		/* Find unused volume ID */
164		dbg_gen("search for vacant volume ID");
165		for (i = 0; i < ubi->vtbl_slots; i++)
166			if (!ubi->volumes[i]) {
167				vol_id = i;
168				break;
169			}
170
171		if (vol_id == UBI_VOL_NUM_AUTO) {
172			ubi_err(ubi, "out of volume IDs");
173			err = -ENFILE;
174			goto out_unlock;
175		}
176		req->vol_id = vol_id;
177	}
178
179	dbg_gen("create device %d, volume %d, %llu bytes, type %d, name %s",
180		ubi->ubi_num, vol_id, (unsigned long long)req->bytes,
181		(int)req->vol_type, req->name);
182
183	/* Ensure that this volume does not exist */
184	err = -EEXIST;
185	if (ubi->volumes[vol_id]) {
186		ubi_err(ubi, "volume %d already exists", vol_id);
187		goto out_unlock;
188	}
189
190	/* Ensure that the name is unique */
191	for (i = 0; i < ubi->vtbl_slots; i++)
192		if (ubi->volumes[i] &&
193		    ubi->volumes[i]->name_len == req->name_len &&
194		    !strcmp(ubi->volumes[i]->name, req->name)) {
195			ubi_err(ubi, "volume \"%s\" exists (ID %d)",
196				req->name, i);
197			goto out_unlock;
198		}
199
200	/* Calculate how many eraseblocks are requested */
201	vol->usable_leb_size = ubi->leb_size - ubi->leb_size % req->alignment;
202	vol->reserved_pebs = div_u64(req->bytes + vol->usable_leb_size - 1,
203				     vol->usable_leb_size);
204
205	/* Reserve physical eraseblocks */
206	if (vol->reserved_pebs > ubi->avail_pebs) {
207		ubi_err(ubi, "not enough PEBs, only %d available",
208			ubi->avail_pebs);
209		if (ubi->corr_peb_count)
210			ubi_err(ubi, "%d PEBs are corrupted and not used",
211				ubi->corr_peb_count);
212		err = -ENOSPC;
213		goto out_unlock;
214	}
215	ubi->avail_pebs -= vol->reserved_pebs;
216	ubi->rsvd_pebs += vol->reserved_pebs;
217	spin_unlock(&ubi->volumes_lock);
218
219	vol->vol_id    = vol_id;
220	vol->alignment = req->alignment;
221	vol->data_pad  = ubi->leb_size % vol->alignment;
222	vol->vol_type  = req->vol_type;
223	vol->name_len  = req->name_len;
224	memcpy(vol->name, req->name, vol->name_len);
225	vol->ubi = ubi;
226
227	/*
228	 * Finish all pending erases because there may be some LEBs belonging
229	 * to the same volume ID.
230	 */
231	err = ubi_wl_flush(ubi, vol_id, UBI_ALL);
232	if (err)
233		goto out_acc;
234
235	eba_tbl = ubi_eba_create_table(vol, vol->reserved_pebs);
236	if (IS_ERR(eba_tbl)) {
237		err = PTR_ERR(eba_tbl);
238		goto out_acc;
239	}
240
241	ubi_eba_replace_table(vol, eba_tbl);
242
243	if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
244		vol->used_ebs = vol->reserved_pebs;
245		vol->last_eb_bytes = vol->usable_leb_size;
246		vol->used_bytes =
247			(long long)vol->used_ebs * vol->usable_leb_size;
248	} else {
249		vol->used_ebs = div_u64_rem(vol->used_bytes,
250					    vol->usable_leb_size,
251					    &vol->last_eb_bytes);
252		if (vol->last_eb_bytes != 0)
253			vol->used_ebs += 1;
254		else
255			vol->last_eb_bytes = vol->usable_leb_size;
256	}
257
258	/* Make volume "available" before it becomes accessible via sysfs */
259	spin_lock(&ubi->volumes_lock);
260	ubi->volumes[vol_id] = vol;
261	ubi->vol_count += 1;
262	spin_unlock(&ubi->volumes_lock);
263
264	/* Register character device for the volume */
265	cdev_init(&vol->cdev, &ubi_vol_cdev_operations);
266	vol->cdev.owner = THIS_MODULE;
267
268	vol->dev.devt = MKDEV(MAJOR(ubi->cdev.dev), vol_id + 1);
269	dev_set_name(&vol->dev, "%s_%d", ubi->ubi_name, vol->vol_id);
270	err = cdev_device_add(&vol->cdev, &vol->dev);
271	if (err) {
272		ubi_err(ubi, "cannot add device");
273		goto out_mapping;
274	}
275
276	/* Fill volume table record */
277	memset(&vtbl_rec, 0, sizeof(struct ubi_vtbl_record));
278	vtbl_rec.reserved_pebs = cpu_to_be32(vol->reserved_pebs);
279	vtbl_rec.alignment     = cpu_to_be32(vol->alignment);
280	vtbl_rec.data_pad      = cpu_to_be32(vol->data_pad);
281	vtbl_rec.name_len      = cpu_to_be16(vol->name_len);
282	if (vol->vol_type == UBI_DYNAMIC_VOLUME)
283		vtbl_rec.vol_type = UBI_VID_DYNAMIC;
284	else
285		vtbl_rec.vol_type = UBI_VID_STATIC;
286
287	if (vol->skip_check)
288		vtbl_rec.flags |= UBI_VTBL_SKIP_CRC_CHECK_FLG;
289
290	memcpy(vtbl_rec.name, vol->name, vol->name_len);
291
292	err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
293	if (err)
294		goto out_sysfs;
295
296	ubi_volume_notify(ubi, vol, UBI_VOLUME_ADDED);
297	self_check_volumes(ubi);
298	return err;
299
300out_sysfs:
301	/*
302	 * We have registered our device, we should not free the volume
303	 * description object in this function in case of an error - it is
304	 * freed by the release function.
305	 */
306	cdev_device_del(&vol->cdev, &vol->dev);
307out_mapping:
308	spin_lock(&ubi->volumes_lock);
309	ubi->volumes[vol_id] = NULL;
310	ubi->vol_count -= 1;
311	spin_unlock(&ubi->volumes_lock);
312out_acc:
313	spin_lock(&ubi->volumes_lock);
314	ubi->rsvd_pebs -= vol->reserved_pebs;
315	ubi->avail_pebs += vol->reserved_pebs;
316out_unlock:
317	spin_unlock(&ubi->volumes_lock);
318	put_device(&vol->dev);
319	ubi_err(ubi, "cannot create volume %d, error %d", vol_id, err);
320	return err;
321}
322
323/**
324 * ubi_remove_volume - remove volume.
325 * @desc: volume descriptor
326 * @no_vtbl: do not change volume table if not zero
327 *
328 * This function removes volume described by @desc. The volume has to be opened
329 * in "exclusive" mode. Returns zero in case of success and a negative error
330 * code in case of failure. The caller has to have the @ubi->device_mutex
331 * locked.
332 */
333int ubi_remove_volume(struct ubi_volume_desc *desc, int no_vtbl)
334{
335	struct ubi_volume *vol = desc->vol;
336	struct ubi_device *ubi = vol->ubi;
337	int i, err, vol_id = vol->vol_id, reserved_pebs = vol->reserved_pebs;
338
339	dbg_gen("remove device %d, volume %d", ubi->ubi_num, vol_id);
340	ubi_assert(desc->mode == UBI_EXCLUSIVE);
341	ubi_assert(vol == ubi->volumes[vol_id]);
342
343	if (ubi->ro_mode)
344		return -EROFS;
345
346	spin_lock(&ubi->volumes_lock);
347	if (vol->ref_count > 1) {
348		/*
349		 * The volume is busy, probably someone is reading one of its
350		 * sysfs files.
351		 */
352		err = -EBUSY;
353		goto out_unlock;
354	}
355	ubi->volumes[vol_id] = NULL;
356	spin_unlock(&ubi->volumes_lock);
357
358	if (!no_vtbl) {
359		err = ubi_change_vtbl_record(ubi, vol_id, NULL);
360		if (err)
361			goto out_err;
362	}
363
364	for (i = 0; i < vol->reserved_pebs; i++) {
365		err = ubi_eba_unmap_leb(ubi, vol, i);
366		if (err)
367			goto out_err;
368	}
369
370	cdev_device_del(&vol->cdev, &vol->dev);
371	put_device(&vol->dev);
372
373	spin_lock(&ubi->volumes_lock);
374	ubi->rsvd_pebs -= reserved_pebs;
375	ubi->avail_pebs += reserved_pebs;
376	ubi_update_reserved(ubi);
377	ubi->vol_count -= 1;
378	spin_unlock(&ubi->volumes_lock);
379
380	ubi_volume_notify(ubi, vol, UBI_VOLUME_REMOVED);
381	if (!no_vtbl)
382		self_check_volumes(ubi);
383
384	return 0;
385
386out_err:
387	ubi_err(ubi, "cannot remove volume %d, error %d", vol_id, err);
388	spin_lock(&ubi->volumes_lock);
389	ubi->volumes[vol_id] = vol;
390out_unlock:
391	spin_unlock(&ubi->volumes_lock);
392	return err;
393}
394
395/**
396 * ubi_resize_volume - re-size volume.
397 * @desc: volume descriptor
398 * @reserved_pebs: new size in physical eraseblocks
399 *
400 * This function re-sizes the volume and returns zero in case of success, and a
401 * negative error code in case of failure. The caller has to have the
402 * @ubi->device_mutex locked.
403 */
404int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs)
405{
406	int i, err, pebs;
407	struct ubi_volume *vol = desc->vol;
408	struct ubi_device *ubi = vol->ubi;
409	struct ubi_vtbl_record vtbl_rec;
410	struct ubi_eba_table *new_eba_tbl = NULL;
411	int vol_id = vol->vol_id;
412
413	if (ubi->ro_mode)
414		return -EROFS;
415
416	dbg_gen("re-size device %d, volume %d to from %d to %d PEBs",
417		ubi->ubi_num, vol_id, vol->reserved_pebs, reserved_pebs);
418
419	if (vol->vol_type == UBI_STATIC_VOLUME &&
420	    reserved_pebs < vol->used_ebs) {
421		ubi_err(ubi, "too small size %d, %d LEBs contain data",
422			reserved_pebs, vol->used_ebs);
423		return -EINVAL;
424	}
425
426	/* If the size is the same, we have nothing to do */
427	if (reserved_pebs == vol->reserved_pebs)
428		return 0;
429
430	new_eba_tbl = ubi_eba_create_table(vol, reserved_pebs);
431	if (IS_ERR(new_eba_tbl))
432		return PTR_ERR(new_eba_tbl);
433
434	spin_lock(&ubi->volumes_lock);
435	if (vol->ref_count > 1) {
436		spin_unlock(&ubi->volumes_lock);
437		err = -EBUSY;
438		goto out_free;
439	}
440	spin_unlock(&ubi->volumes_lock);
441
442	/* Reserve physical eraseblocks */
443	pebs = reserved_pebs - vol->reserved_pebs;
444	if (pebs > 0) {
445		spin_lock(&ubi->volumes_lock);
446		if (pebs > ubi->avail_pebs) {
447			ubi_err(ubi, "not enough PEBs: requested %d, available %d",
448				pebs, ubi->avail_pebs);
449			if (ubi->corr_peb_count)
450				ubi_err(ubi, "%d PEBs are corrupted and not used",
451					ubi->corr_peb_count);
452			spin_unlock(&ubi->volumes_lock);
453			err = -ENOSPC;
454			goto out_free;
455		}
456		ubi->avail_pebs -= pebs;
457		ubi->rsvd_pebs += pebs;
458		ubi_eba_copy_table(vol, new_eba_tbl, vol->reserved_pebs);
459		ubi_eba_replace_table(vol, new_eba_tbl);
460		spin_unlock(&ubi->volumes_lock);
461	}
462
463	if (pebs < 0) {
464		for (i = 0; i < -pebs; i++) {
465			err = ubi_eba_unmap_leb(ubi, vol, reserved_pebs + i);
466			if (err)
467				goto out_free;
468		}
469		spin_lock(&ubi->volumes_lock);
470		ubi->rsvd_pebs += pebs;
471		ubi->avail_pebs -= pebs;
472		ubi_update_reserved(ubi);
473		ubi_eba_copy_table(vol, new_eba_tbl, reserved_pebs);
474		ubi_eba_replace_table(vol, new_eba_tbl);
475		spin_unlock(&ubi->volumes_lock);
476	}
477
478	/*
479	 * When we shrink a volume we have to flush all pending (erase) work.
480	 * Otherwise it can happen that upon next attach UBI finds a LEB with
481	 * lnum > highest_lnum and refuses to attach.
482	 */
483	if (pebs < 0) {
484		err = ubi_wl_flush(ubi, vol_id, UBI_ALL);
485		if (err)
486			goto out_acc;
487	}
488
489	/* Change volume table record */
490	vtbl_rec = ubi->vtbl[vol_id];
491	vtbl_rec.reserved_pebs = cpu_to_be32(reserved_pebs);
492	err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
493	if (err)
494		goto out_acc;
495
496	vol->reserved_pebs = reserved_pebs;
497	if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
498		vol->used_ebs = reserved_pebs;
499		vol->last_eb_bytes = vol->usable_leb_size;
500		vol->used_bytes =
501			(long long)vol->used_ebs * vol->usable_leb_size;
502	}
503
504	ubi_volume_notify(ubi, vol, UBI_VOLUME_RESIZED);
505	self_check_volumes(ubi);
506	return err;
507
508out_acc:
509	if (pebs > 0) {
510		spin_lock(&ubi->volumes_lock);
511		ubi->rsvd_pebs -= pebs;
512		ubi->avail_pebs += pebs;
513		spin_unlock(&ubi->volumes_lock);
514	}
515	return err;
516
517out_free:
518	ubi_eba_destroy_table(new_eba_tbl);
519	return err;
520}
521
522/**
523 * ubi_rename_volumes - re-name UBI volumes.
524 * @ubi: UBI device description object
525 * @rename_list: list of &struct ubi_rename_entry objects
526 *
527 * This function re-names or removes volumes specified in the re-name list.
528 * Returns zero in case of success and a negative error code in case of
529 * failure.
530 */
531int ubi_rename_volumes(struct ubi_device *ubi, struct list_head *rename_list)
532{
533	int err;
534	struct ubi_rename_entry *re;
535
536	err = ubi_vtbl_rename_volumes(ubi, rename_list);
537	if (err)
538		return err;
539
540	list_for_each_entry(re, rename_list, list) {
541		if (re->remove) {
542			err = ubi_remove_volume(re->desc, 1);
543			if (err)
544				break;
545		} else {
546			struct ubi_volume *vol = re->desc->vol;
547
548			spin_lock(&ubi->volumes_lock);
549			vol->name_len = re->new_name_len;
550			memcpy(vol->name, re->new_name, re->new_name_len + 1);
551			spin_unlock(&ubi->volumes_lock);
552			ubi_volume_notify(ubi, vol, UBI_VOLUME_RENAMED);
553		}
554	}
555
556	if (!err)
557		self_check_volumes(ubi);
558	return err;
559}
560
561/**
562 * ubi_add_volume - add volume.
563 * @ubi: UBI device description object
564 * @vol: volume description object
565 *
566 * This function adds an existing volume and initializes all its data
567 * structures. Returns zero in case of success and a negative error code in
568 * case of failure.
569 */
570int ubi_add_volume(struct ubi_device *ubi, struct ubi_volume *vol)
571{
572	int err, vol_id = vol->vol_id;
573	dev_t dev;
574
575	dbg_gen("add volume %d", vol_id);
576
577	/* Register character device for the volume */
578	cdev_init(&vol->cdev, &ubi_vol_cdev_operations);
579	vol->cdev.owner = THIS_MODULE;
580	dev = MKDEV(MAJOR(ubi->cdev.dev), vol->vol_id + 1);
581	err = cdev_add(&vol->cdev, dev, 1);
582	if (err) {
583		ubi_err(ubi, "cannot add character device for volume %d, error %d",
584			vol_id, err);
585		vol_release(&vol->dev);
586		return err;
587	}
588
589	vol->dev.release = vol_release;
590	vol->dev.parent = &ubi->dev;
591	vol->dev.devt = dev;
592	vol->dev.class = &ubi_class;
593	vol->dev.groups = volume_dev_groups;
594	dev_set_name(&vol->dev, "%s_%d", ubi->ubi_name, vol->vol_id);
595	err = device_register(&vol->dev);
596	if (err) {
597		cdev_del(&vol->cdev);
598		put_device(&vol->dev);
599		return err;
600	}
601
602	self_check_volumes(ubi);
603	return err;
604}
605
606/**
607 * ubi_free_volume - free volume.
608 * @ubi: UBI device description object
609 * @vol: volume description object
610 *
611 * This function frees all resources for volume @vol but does not remove it.
612 * Used only when the UBI device is detached.
613 */
614void ubi_free_volume(struct ubi_device *ubi, struct ubi_volume *vol)
615{
616	dbg_gen("free volume %d", vol->vol_id);
617
618	ubi->volumes[vol->vol_id] = NULL;
619	cdev_del(&vol->cdev);
620	device_unregister(&vol->dev);
621}
622
623/**
624 * self_check_volume - check volume information.
625 * @ubi: UBI device description object
626 * @vol_id: volume ID
627 *
628 * Returns zero if volume is all right and a negative error code if not.
629 */
630static int self_check_volume(struct ubi_device *ubi, int vol_id)
631{
632	int idx = vol_id2idx(ubi, vol_id);
633	int reserved_pebs, alignment, data_pad, vol_type, name_len, upd_marker;
634	const struct ubi_volume *vol;
635	long long n;
636	const char *name;
637
638	spin_lock(&ubi->volumes_lock);
639	reserved_pebs = be32_to_cpu(ubi->vtbl[vol_id].reserved_pebs);
640	vol = ubi->volumes[idx];
641
642	if (!vol) {
643		if (reserved_pebs) {
644			ubi_err(ubi, "no volume info, but volume exists");
645			goto fail;
646		}
647		spin_unlock(&ubi->volumes_lock);
648		return 0;
649	}
650
651	if (vol->reserved_pebs < 0 || vol->alignment < 0 || vol->data_pad < 0 ||
652	    vol->name_len < 0) {
653		ubi_err(ubi, "negative values");
654		goto fail;
655	}
656	if (vol->alignment > ubi->leb_size || vol->alignment == 0) {
657		ubi_err(ubi, "bad alignment");
658		goto fail;
659	}
660
661	n = vol->alignment & (ubi->min_io_size - 1);
662	if (vol->alignment != 1 && n) {
663		ubi_err(ubi, "alignment is not multiple of min I/O unit");
664		goto fail;
665	}
666
667	n = ubi->leb_size % vol->alignment;
668	if (vol->data_pad != n) {
669		ubi_err(ubi, "bad data_pad, has to be %lld", n);
670		goto fail;
671	}
672
673	if (vol->vol_type != UBI_DYNAMIC_VOLUME &&
674	    vol->vol_type != UBI_STATIC_VOLUME) {
675		ubi_err(ubi, "bad vol_type");
676		goto fail;
677	}
678
679	if (vol->upd_marker && vol->corrupted) {
680		ubi_err(ubi, "update marker and corrupted simultaneously");
681		goto fail;
682	}
683
684	if (vol->reserved_pebs > ubi->good_peb_count) {
685		ubi_err(ubi, "too large reserved_pebs");
686		goto fail;
687	}
688
689	n = ubi->leb_size - vol->data_pad;
690	if (vol->usable_leb_size != ubi->leb_size - vol->data_pad) {
691		ubi_err(ubi, "bad usable_leb_size, has to be %lld", n);
692		goto fail;
693	}
694
695	if (vol->name_len > UBI_VOL_NAME_MAX) {
696		ubi_err(ubi, "too long volume name, max is %d",
697			UBI_VOL_NAME_MAX);
698		goto fail;
699	}
700
701	n = strnlen(vol->name, vol->name_len + 1);
702	if (n != vol->name_len) {
703		ubi_err(ubi, "bad name_len %lld", n);
704		goto fail;
705	}
706
707	n = (long long)vol->used_ebs * vol->usable_leb_size;
708	if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
709		if (vol->corrupted) {
710			ubi_err(ubi, "corrupted dynamic volume");
711			goto fail;
712		}
713		if (vol->used_ebs != vol->reserved_pebs) {
714			ubi_err(ubi, "bad used_ebs");
715			goto fail;
716		}
717		if (vol->last_eb_bytes != vol->usable_leb_size) {
718			ubi_err(ubi, "bad last_eb_bytes");
719			goto fail;
720		}
721		if (vol->used_bytes != n) {
722			ubi_err(ubi, "bad used_bytes");
723			goto fail;
724		}
725
726		if (vol->skip_check) {
727			ubi_err(ubi, "bad skip_check");
728			goto fail;
729		}
730	} else {
731		if (vol->used_ebs < 0 || vol->used_ebs > vol->reserved_pebs) {
732			ubi_err(ubi, "bad used_ebs");
733			goto fail;
734		}
735		if (vol->last_eb_bytes < 0 ||
736		    vol->last_eb_bytes > vol->usable_leb_size) {
737			ubi_err(ubi, "bad last_eb_bytes");
738			goto fail;
739		}
740		if (vol->used_bytes < 0 || vol->used_bytes > n ||
741		    vol->used_bytes < n - vol->usable_leb_size) {
742			ubi_err(ubi, "bad used_bytes");
743			goto fail;
744		}
745	}
746
747	alignment  = be32_to_cpu(ubi->vtbl[vol_id].alignment);
748	data_pad   = be32_to_cpu(ubi->vtbl[vol_id].data_pad);
749	name_len   = be16_to_cpu(ubi->vtbl[vol_id].name_len);
750	upd_marker = ubi->vtbl[vol_id].upd_marker;
751	name       = &ubi->vtbl[vol_id].name[0];
752	if (ubi->vtbl[vol_id].vol_type == UBI_VID_DYNAMIC)
753		vol_type = UBI_DYNAMIC_VOLUME;
754	else
755		vol_type = UBI_STATIC_VOLUME;
756
757	if (alignment != vol->alignment || data_pad != vol->data_pad ||
758	    upd_marker != vol->upd_marker || vol_type != vol->vol_type ||
759	    name_len != vol->name_len || strncmp(name, vol->name, name_len)) {
760		ubi_err(ubi, "volume info is different");
761		goto fail;
762	}
763
764	spin_unlock(&ubi->volumes_lock);
765	return 0;
766
767fail:
768	ubi_err(ubi, "self-check failed for volume %d", vol_id);
769	if (vol)
770		ubi_dump_vol_info(vol);
771	ubi_dump_vtbl_record(&ubi->vtbl[vol_id], vol_id);
772	dump_stack();
773	spin_unlock(&ubi->volumes_lock);
774	return -EINVAL;
775}
776
777/**
778 * self_check_volumes - check information about all volumes.
779 * @ubi: UBI device description object
780 *
781 * Returns zero if volumes are all right and a negative error code if not.
782 */
783static int self_check_volumes(struct ubi_device *ubi)
784{
785	int i, err = 0;
786
787	if (!ubi_dbg_chk_gen(ubi))
788		return 0;
789
790	for (i = 0; i < ubi->vtbl_slots; i++) {
791		err = self_check_volume(ubi, i);
792		if (err)
793			break;
794	}
795
796	return err;
797}
798