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 <log.h>
15 #include <dm/devres.h>
16 #include <linux/err.h>
17 #include <linux/slab.h>
18 #include <linux/export.h>
19 #else
20 #include <div64.h>
21 #include <ubi_uboot.h>
22 #endif
23 #include <linux/math64.h>
24 
25 #include "ubi.h"
26 
27 static int self_check_volumes(struct ubi_device *ubi);
28 
29 #ifndef __UBOOT__
30 static ssize_t vol_attribute_show(struct device *dev,
31 				  struct device_attribute *attr, char *buf);
32 
33 /* Device attributes corresponding to files in '/<sysfs>/class/ubi/ubiX_Y' */
34 static struct device_attribute attr_vol_reserved_ebs =
35 	__ATTR(reserved_ebs, S_IRUGO, vol_attribute_show, NULL);
36 static struct device_attribute attr_vol_type =
37 	__ATTR(type, S_IRUGO, vol_attribute_show, NULL);
38 static struct device_attribute attr_vol_name =
39 	__ATTR(name, S_IRUGO, vol_attribute_show, NULL);
40 static struct device_attribute attr_vol_corrupted =
41 	__ATTR(corrupted, S_IRUGO, vol_attribute_show, NULL);
42 static struct device_attribute attr_vol_alignment =
43 	__ATTR(alignment, S_IRUGO, vol_attribute_show, NULL);
44 static struct device_attribute attr_vol_usable_eb_size =
45 	__ATTR(usable_eb_size, S_IRUGO, vol_attribute_show, NULL);
46 static struct device_attribute attr_vol_data_bytes =
47 	__ATTR(data_bytes, S_IRUGO, vol_attribute_show, NULL);
48 static struct device_attribute attr_vol_upd_marker =
49 	__ATTR(upd_marker, S_IRUGO, vol_attribute_show, NULL);
50 
51 /*
52  * "Show" method for files in '/<sysfs>/class/ubi/ubiX_Y/'.
53  *
54  * Consider a situation:
55  * A. process 1 opens a sysfs file related to volume Y, say
56  *    /<sysfs>/class/ubi/ubiX_Y/reserved_ebs;
57  * B. process 2 removes volume Y;
58  * C. process 1 starts reading the /<sysfs>/class/ubi/ubiX_Y/reserved_ebs file;
59  *
60  * In this situation, this function will return %-ENODEV because it will find
61  * out that the volume was removed from the @ubi->volumes array.
62  */
vol_attribute_show(struct device * dev,struct device_attribute * attr,char * buf)63 static ssize_t vol_attribute_show(struct device *dev,
64 				  struct device_attribute *attr, char *buf)
65 {
66 	int ret;
67 	struct ubi_volume *vol = container_of(dev, struct ubi_volume, dev);
68 	struct ubi_device *ubi;
69 
70 	ubi = ubi_get_device(vol->ubi->ubi_num);
71 	if (!ubi)
72 		return -ENODEV;
73 
74 	spin_lock(&ubi->volumes_lock);
75 	if (!ubi->volumes[vol->vol_id]) {
76 		spin_unlock(&ubi->volumes_lock);
77 		ubi_put_device(ubi);
78 		return -ENODEV;
79 	}
80 	/* Take a reference to prevent volume removal */
81 	vol->ref_count += 1;
82 	spin_unlock(&ubi->volumes_lock);
83 
84 	if (attr == &attr_vol_reserved_ebs)
85 		ret = sprintf(buf, "%d\n", vol->reserved_pebs);
86 	else if (attr == &attr_vol_type) {
87 		const char *tp;
88 
89 		if (vol->vol_type == UBI_DYNAMIC_VOLUME)
90 			tp = "dynamic";
91 		else
92 			tp = "static";
93 		ret = sprintf(buf, "%s\n", tp);
94 	} else if (attr == &attr_vol_name)
95 		ret = sprintf(buf, "%s\n", vol->name);
96 	else if (attr == &attr_vol_corrupted)
97 		ret = sprintf(buf, "%d\n", vol->corrupted);
98 	else if (attr == &attr_vol_alignment)
99 		ret = sprintf(buf, "%d\n", vol->alignment);
100 	else if (attr == &attr_vol_usable_eb_size)
101 		ret = sprintf(buf, "%d\n", vol->usable_leb_size);
102 	else if (attr == &attr_vol_data_bytes)
103 		ret = sprintf(buf, "%lld\n", vol->used_bytes);
104 	else if (attr == &attr_vol_upd_marker)
105 		ret = sprintf(buf, "%d\n", vol->upd_marker);
106 	else
107 		/* This must be a bug */
108 		ret = -EINVAL;
109 
110 	/* We've done the operation, drop volume and UBI device references */
111 	spin_lock(&ubi->volumes_lock);
112 	vol->ref_count -= 1;
113 	ubi_assert(vol->ref_count >= 0);
114 	spin_unlock(&ubi->volumes_lock);
115 	ubi_put_device(ubi);
116 	return ret;
117 }
118 
119 static struct attribute *volume_dev_attrs[] = {
120 	&attr_vol_reserved_ebs.attr,
121 	&attr_vol_type.attr,
122 	&attr_vol_name.attr,
123 	&attr_vol_corrupted.attr,
124 	&attr_vol_alignment.attr,
125 	&attr_vol_usable_eb_size.attr,
126 	&attr_vol_data_bytes.attr,
127 	&attr_vol_upd_marker.attr,
128 	NULL
129 };
130 ATTRIBUTE_GROUPS(volume_dev);
131 #endif
132 
133 /* Release method for volume devices */
vol_release(struct device * dev)134 static void vol_release(struct device *dev)
135 {
136 	struct ubi_volume *vol = container_of(dev, struct ubi_volume, dev);
137 
138 	kfree(vol->eba_tbl);
139 	kfree(vol);
140 }
141 
142 /**
143  * ubi_create_volume - create volume.
144  * @ubi: UBI device description object
145  * @req: volume creation request
146  *
147  * This function creates volume described by @req. If @req->vol_id id
148  * %UBI_VOL_NUM_AUTO, this function automatically assign ID to the new volume
149  * and saves it in @req->vol_id. Returns zero in case of success and a negative
150  * error code in case of failure. Note, the caller has to have the
151  * @ubi->device_mutex locked.
152  */
ubi_create_volume(struct ubi_device * ubi,struct ubi_mkvol_req * req)153 int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req)
154 {
155 	int i, err, vol_id = req->vol_id, do_free = 1;
156 	struct ubi_volume *vol;
157 	struct ubi_vtbl_record vtbl_rec;
158 	dev_t dev;
159 
160 	if (ubi->ro_mode)
161 		return -EROFS;
162 
163 	vol = kzalloc(sizeof(struct ubi_volume), GFP_KERNEL);
164 	if (!vol)
165 		return -ENOMEM;
166 
167 	if (req->flags & UBI_VOL_SKIP_CRC_CHECK_FLG)
168 		vol->skip_check = 1;
169 
170 	spin_lock(&ubi->volumes_lock);
171 	if (vol_id == UBI_VOL_NUM_AUTO) {
172 		/* Find unused volume ID */
173 		dbg_gen("search for vacant volume ID");
174 		for (i = 0; i < ubi->vtbl_slots; i++)
175 			if (!ubi->volumes[i]) {
176 				vol_id = i;
177 				break;
178 			}
179 
180 		if (vol_id == UBI_VOL_NUM_AUTO) {
181 			ubi_err(ubi, "out of volume IDs");
182 			err = -ENFILE;
183 			goto out_unlock;
184 		}
185 		req->vol_id = vol_id;
186 	}
187 
188 	dbg_gen("create device %d, volume %d, %llu bytes, type %d, name %s",
189 		ubi->ubi_num, vol_id, (unsigned long long)req->bytes,
190 		(int)req->vol_type, req->name);
191 
192 	/* Ensure that this volume does not exist */
193 	err = -EEXIST;
194 	if (ubi->volumes[vol_id]) {
195 		ubi_err(ubi, "volume %d already exists", vol_id);
196 		goto out_unlock;
197 	}
198 
199 	/* Ensure that the name is unique */
200 	for (i = 0; i < ubi->vtbl_slots; i++)
201 		if (ubi->volumes[i] &&
202 		    ubi->volumes[i]->name_len == req->name_len &&
203 		    !strcmp(ubi->volumes[i]->name, req->name)) {
204 			ubi_err(ubi, "volume \"%s\" exists (ID %d)",
205 				req->name, i);
206 			goto out_unlock;
207 		}
208 
209 	/* Calculate how many eraseblocks are requested */
210 	vol->usable_leb_size = ubi->leb_size - ubi->leb_size % req->alignment;
211 	vol->reserved_pebs = div_u64(req->bytes + vol->usable_leb_size - 1,
212 				     vol->usable_leb_size);
213 
214 	/* Reserve physical eraseblocks */
215 	if (vol->reserved_pebs > ubi->avail_pebs) {
216 		ubi_err(ubi, "not enough PEBs, only %d available",
217 			ubi->avail_pebs);
218 		if (ubi->corr_peb_count)
219 			ubi_err(ubi, "%d PEBs are corrupted and not used",
220 				ubi->corr_peb_count);
221 		err = -ENOSPC;
222 		goto out_unlock;
223 	}
224 	ubi->avail_pebs -= vol->reserved_pebs;
225 	ubi->rsvd_pebs += vol->reserved_pebs;
226 	spin_unlock(&ubi->volumes_lock);
227 
228 	vol->vol_id    = vol_id;
229 	vol->alignment = req->alignment;
230 	vol->data_pad  = ubi->leb_size % vol->alignment;
231 	vol->vol_type  = req->vol_type;
232 	vol->name_len  = req->name_len;
233 	memcpy(vol->name, req->name, vol->name_len);
234 	vol->ubi = ubi;
235 
236 	/*
237 	 * Finish all pending erases because there may be some LEBs belonging
238 	 * to the same volume ID.
239 	 */
240 	err = ubi_wl_flush(ubi, vol_id, UBI_ALL);
241 	if (err)
242 		goto out_acc;
243 
244 	vol->eba_tbl = kmalloc(vol->reserved_pebs * sizeof(int), GFP_KERNEL);
245 	if (!vol->eba_tbl) {
246 		err = -ENOMEM;
247 		goto out_acc;
248 	}
249 
250 	for (i = 0; i < vol->reserved_pebs; i++)
251 		vol->eba_tbl[i] = UBI_LEB_UNMAPPED;
252 
253 	if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
254 		vol->used_ebs = vol->reserved_pebs;
255 		vol->last_eb_bytes = vol->usable_leb_size;
256 		vol->used_bytes =
257 			(long long)vol->used_ebs * vol->usable_leb_size;
258 	} else {
259 		vol->used_ebs = div_u64_rem(vol->used_bytes,
260 					    vol->usable_leb_size,
261 					    &vol->last_eb_bytes);
262 		if (vol->last_eb_bytes != 0)
263 			vol->used_ebs += 1;
264 		else
265 			vol->last_eb_bytes = vol->usable_leb_size;
266 	}
267 
268 	/* Register character device for the volume */
269 	cdev_init(&vol->cdev, &ubi_vol_cdev_operations);
270 	vol->cdev.owner = THIS_MODULE;
271 	dev = MKDEV(MAJOR(ubi->cdev.dev), vol_id + 1);
272 	err = cdev_add(&vol->cdev, dev, 1);
273 	if (err) {
274 		ubi_err(ubi, "cannot add character device");
275 		goto out_mapping;
276 	}
277 
278 	vol->dev.release = vol_release;
279 	vol->dev.parent = &ubi->dev;
280 	vol->dev.devt = dev;
281 #ifndef __UBOOT__
282 	vol->dev.class = &ubi_class;
283 	vol->dev.groups = volume_dev_groups;
284 #endif
285 
286 	dev_set_name(&vol->dev, "%s_%d", ubi->ubi_name, vol->vol_id);
287 	err = device_register(&vol->dev);
288 	if (err) {
289 		ubi_err(ubi, "cannot register device");
290 		goto out_cdev;
291 	}
292 
293 	/* Fill volume table record */
294 	memset(&vtbl_rec, 0, sizeof(struct ubi_vtbl_record));
295 	vtbl_rec.reserved_pebs = cpu_to_be32(vol->reserved_pebs);
296 	vtbl_rec.alignment     = cpu_to_be32(vol->alignment);
297 	vtbl_rec.data_pad      = cpu_to_be32(vol->data_pad);
298 	vtbl_rec.name_len      = cpu_to_be16(vol->name_len);
299 	if (vol->vol_type == UBI_DYNAMIC_VOLUME)
300 		vtbl_rec.vol_type = UBI_VID_DYNAMIC;
301 	else
302 		vtbl_rec.vol_type = UBI_VID_STATIC;
303 
304 	if (vol->skip_check)
305 		vtbl_rec.flags |= UBI_VTBL_SKIP_CRC_CHECK_FLG;
306 
307 	memcpy(vtbl_rec.name, vol->name, vol->name_len);
308 
309 	err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
310 	if (err)
311 		goto out_sysfs;
312 
313 	spin_lock(&ubi->volumes_lock);
314 	ubi->volumes[vol_id] = vol;
315 	ubi->vol_count += 1;
316 	spin_unlock(&ubi->volumes_lock);
317 
318 	ubi_volume_notify(ubi, vol, UBI_VOLUME_ADDED);
319 	self_check_volumes(ubi);
320 	return err;
321 
322 out_sysfs:
323 	/*
324 	 * We have registered our device, we should not free the volume
325 	 * description object in this function in case of an error - it is
326 	 * freed by the release function.
327 	 *
328 	 * Get device reference to prevent the release function from being
329 	 * called just after sysfs has been closed.
330 	 */
331 	do_free = 0;
332 	get_device(&vol->dev);
333 	device_unregister(&vol->dev);
334 out_cdev:
335 	cdev_del(&vol->cdev);
336 out_mapping:
337 	if (do_free)
338 		kfree(vol->eba_tbl);
339 out_acc:
340 	spin_lock(&ubi->volumes_lock);
341 	ubi->rsvd_pebs -= vol->reserved_pebs;
342 	ubi->avail_pebs += vol->reserved_pebs;
343 out_unlock:
344 	spin_unlock(&ubi->volumes_lock);
345 	if (do_free)
346 		kfree(vol);
347 	else
348 		put_device(&vol->dev);
349 	ubi_err(ubi, "cannot create volume %d, error %d", vol_id, err);
350 	return err;
351 }
352 
353 /**
354  * ubi_remove_volume - remove volume.
355  * @desc: volume descriptor
356  * @no_vtbl: do not change volume table if not zero
357  *
358  * This function removes volume described by @desc. The volume has to be opened
359  * in "exclusive" mode. Returns zero in case of success and a negative error
360  * code in case of failure. The caller has to have the @ubi->device_mutex
361  * locked.
362  */
ubi_remove_volume(struct ubi_volume_desc * desc,int no_vtbl)363 int ubi_remove_volume(struct ubi_volume_desc *desc, int no_vtbl)
364 {
365 	struct ubi_volume *vol = desc->vol;
366 	struct ubi_device *ubi = vol->ubi;
367 	int i, err, vol_id = vol->vol_id, reserved_pebs = vol->reserved_pebs;
368 
369 	dbg_gen("remove device %d, volume %d", ubi->ubi_num, vol_id);
370 	ubi_assert(desc->mode == UBI_EXCLUSIVE);
371 	ubi_assert(vol == ubi->volumes[vol_id]);
372 
373 	if (ubi->ro_mode)
374 		return -EROFS;
375 
376 	spin_lock(&ubi->volumes_lock);
377 	if (vol->ref_count > 1) {
378 		/*
379 		 * The volume is busy, probably someone is reading one of its
380 		 * sysfs files.
381 		 */
382 		err = -EBUSY;
383 		goto out_unlock;
384 	}
385 	ubi->volumes[vol_id] = NULL;
386 	spin_unlock(&ubi->volumes_lock);
387 
388 	if (!no_vtbl) {
389 		err = ubi_change_vtbl_record(ubi, vol_id, NULL);
390 		if (err)
391 			goto out_err;
392 	}
393 
394 	for (i = 0; i < vol->reserved_pebs; i++) {
395 		err = ubi_eba_unmap_leb(ubi, vol, i);
396 		if (err)
397 			goto out_err;
398 	}
399 
400 	cdev_del(&vol->cdev);
401 	device_unregister(&vol->dev);
402 
403 	spin_lock(&ubi->volumes_lock);
404 	ubi->rsvd_pebs -= reserved_pebs;
405 	ubi->avail_pebs += reserved_pebs;
406 	ubi_update_reserved(ubi);
407 	ubi->vol_count -= 1;
408 	spin_unlock(&ubi->volumes_lock);
409 
410 	ubi_volume_notify(ubi, vol, UBI_VOLUME_REMOVED);
411 	if (!no_vtbl)
412 		self_check_volumes(ubi);
413 
414 	return err;
415 
416 out_err:
417 	ubi_err(ubi, "cannot remove volume %d, error %d", vol_id, err);
418 	spin_lock(&ubi->volumes_lock);
419 	ubi->volumes[vol_id] = vol;
420 out_unlock:
421 	spin_unlock(&ubi->volumes_lock);
422 	return err;
423 }
424 
425 /**
426  * ubi_resize_volume - re-size volume.
427  * @desc: volume descriptor
428  * @reserved_pebs: new size in physical eraseblocks
429  *
430  * This function re-sizes the volume and returns zero in case of success, and a
431  * negative error code in case of failure. The caller has to have the
432  * @ubi->device_mutex locked.
433  */
ubi_resize_volume(struct ubi_volume_desc * desc,int reserved_pebs)434 int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs)
435 {
436 	int i, err, pebs, *new_mapping;
437 	struct ubi_volume *vol = desc->vol;
438 	struct ubi_device *ubi = vol->ubi;
439 	struct ubi_vtbl_record vtbl_rec;
440 	int vol_id = vol->vol_id;
441 
442 	if (ubi->ro_mode)
443 		return -EROFS;
444 
445 	dbg_gen("re-size device %d, volume %d to from %d to %d PEBs",
446 		ubi->ubi_num, vol_id, vol->reserved_pebs, reserved_pebs);
447 
448 	if (vol->vol_type == UBI_STATIC_VOLUME &&
449 	    reserved_pebs < vol->used_ebs) {
450 		ubi_err(ubi, "too small size %d, %d LEBs contain data",
451 			reserved_pebs, vol->used_ebs);
452 		return -EINVAL;
453 	}
454 
455 	/* If the size is the same, we have nothing to do */
456 	if (reserved_pebs == vol->reserved_pebs)
457 		return 0;
458 
459 	new_mapping = kmalloc(reserved_pebs * sizeof(int), GFP_KERNEL);
460 	if (!new_mapping)
461 		return -ENOMEM;
462 
463 	for (i = 0; i < reserved_pebs; i++)
464 		new_mapping[i] = UBI_LEB_UNMAPPED;
465 
466 	spin_lock(&ubi->volumes_lock);
467 	if (vol->ref_count > 1) {
468 		spin_unlock(&ubi->volumes_lock);
469 		err = -EBUSY;
470 		goto out_free;
471 	}
472 	spin_unlock(&ubi->volumes_lock);
473 
474 	/* Reserve physical eraseblocks */
475 	pebs = reserved_pebs - vol->reserved_pebs;
476 	if (pebs > 0) {
477 		spin_lock(&ubi->volumes_lock);
478 		if (pebs > ubi->avail_pebs) {
479 			ubi_err(ubi, "not enough PEBs: requested %d, available %d",
480 				pebs, ubi->avail_pebs);
481 			if (ubi->corr_peb_count)
482 				ubi_err(ubi, "%d PEBs are corrupted and not used",
483 					ubi->corr_peb_count);
484 			spin_unlock(&ubi->volumes_lock);
485 			err = -ENOSPC;
486 			goto out_free;
487 		}
488 		ubi->avail_pebs -= pebs;
489 		ubi->rsvd_pebs += pebs;
490 		for (i = 0; i < vol->reserved_pebs; i++)
491 			new_mapping[i] = vol->eba_tbl[i];
492 		kfree(vol->eba_tbl);
493 		vol->eba_tbl = new_mapping;
494 		spin_unlock(&ubi->volumes_lock);
495 	}
496 
497 	/* Change volume table record */
498 	vtbl_rec = ubi->vtbl[vol_id];
499 	vtbl_rec.reserved_pebs = cpu_to_be32(reserved_pebs);
500 	err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
501 	if (err)
502 		goto out_acc;
503 
504 	if (pebs < 0) {
505 		for (i = 0; i < -pebs; i++) {
506 			err = ubi_eba_unmap_leb(ubi, vol, reserved_pebs + i);
507 			if (err)
508 				goto out_acc;
509 		}
510 		spin_lock(&ubi->volumes_lock);
511 		ubi->rsvd_pebs += pebs;
512 		ubi->avail_pebs -= pebs;
513 		ubi_update_reserved(ubi);
514 		for (i = 0; i < reserved_pebs; i++)
515 			new_mapping[i] = vol->eba_tbl[i];
516 		kfree(vol->eba_tbl);
517 		vol->eba_tbl = new_mapping;
518 		spin_unlock(&ubi->volumes_lock);
519 	}
520 
521 	vol->reserved_pebs = reserved_pebs;
522 	if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
523 		vol->used_ebs = reserved_pebs;
524 		vol->last_eb_bytes = vol->usable_leb_size;
525 		vol->used_bytes =
526 			(long long)vol->used_ebs * vol->usable_leb_size;
527 	}
528 
529 	ubi_volume_notify(ubi, vol, UBI_VOLUME_RESIZED);
530 	self_check_volumes(ubi);
531 	return err;
532 
533 out_acc:
534 	if (pebs > 0) {
535 		spin_lock(&ubi->volumes_lock);
536 		ubi->rsvd_pebs -= pebs;
537 		ubi->avail_pebs += pebs;
538 		spin_unlock(&ubi->volumes_lock);
539 	}
540 out_free:
541 	kfree(new_mapping);
542 	return err;
543 }
544 
545 /**
546  * ubi_rename_volumes - re-name UBI volumes.
547  * @ubi: UBI device description object
548  * @rename_list: list of &struct ubi_rename_entry objects
549  *
550  * This function re-names or removes volumes specified in the re-name list.
551  * Returns zero in case of success and a negative error code in case of
552  * failure.
553  */
ubi_rename_volumes(struct ubi_device * ubi,struct list_head * rename_list)554 int ubi_rename_volumes(struct ubi_device *ubi, struct list_head *rename_list)
555 {
556 	int err;
557 	struct ubi_rename_entry *re;
558 
559 	err = ubi_vtbl_rename_volumes(ubi, rename_list);
560 	if (err)
561 		return err;
562 
563 	list_for_each_entry(re, rename_list, list) {
564 		if (re->remove) {
565 			err = ubi_remove_volume(re->desc, 1);
566 			if (err)
567 				break;
568 		} else {
569 			struct ubi_volume *vol = re->desc->vol;
570 
571 			spin_lock(&ubi->volumes_lock);
572 			vol->name_len = re->new_name_len;
573 			memcpy(vol->name, re->new_name, re->new_name_len + 1);
574 			spin_unlock(&ubi->volumes_lock);
575 			ubi_volume_notify(ubi, vol, UBI_VOLUME_RENAMED);
576 		}
577 	}
578 
579 	if (!err)
580 		self_check_volumes(ubi);
581 	return err;
582 }
583 
584 /**
585  * ubi_add_volume - add volume.
586  * @ubi: UBI device description object
587  * @vol: volume description object
588  *
589  * This function adds an existing volume and initializes all its data
590  * structures. Returns zero in case of success and a negative error code in
591  * case of failure.
592  */
ubi_add_volume(struct ubi_device * ubi,struct ubi_volume * vol)593 int ubi_add_volume(struct ubi_device *ubi, struct ubi_volume *vol)
594 {
595 	int err, vol_id = vol->vol_id;
596 	dev_t dev;
597 
598 	dbg_gen("add volume %d", vol_id);
599 
600 	/* Register character device for the volume */
601 	cdev_init(&vol->cdev, &ubi_vol_cdev_operations);
602 	vol->cdev.owner = THIS_MODULE;
603 	dev = MKDEV(MAJOR(ubi->cdev.dev), vol->vol_id + 1);
604 	err = cdev_add(&vol->cdev, dev, 1);
605 	if (err) {
606 		ubi_err(ubi, "cannot add character device for volume %d, error %d",
607 			vol_id, err);
608 		return err;
609 	}
610 
611 	vol->dev.release = vol_release;
612 	vol->dev.parent = &ubi->dev;
613 	vol->dev.devt = dev;
614 #ifndef __UBOOT__
615 	vol->dev.class = &ubi_class;
616 	vol->dev.groups = volume_dev_groups;
617 #endif
618 	dev_set_name(&vol->dev, "%s_%d", ubi->ubi_name, vol->vol_id);
619 	err = device_register(&vol->dev);
620 	if (err)
621 		goto out_cdev;
622 
623 	self_check_volumes(ubi);
624 	return err;
625 
626 out_cdev:
627 	cdev_del(&vol->cdev);
628 	return err;
629 }
630 
631 /**
632  * ubi_free_volume - free volume.
633  * @ubi: UBI device description object
634  * @vol: volume description object
635  *
636  * This function frees all resources for volume @vol but does not remove it.
637  * Used only when the UBI device is detached.
638  */
ubi_free_volume(struct ubi_device * ubi,struct ubi_volume * vol)639 void ubi_free_volume(struct ubi_device *ubi, struct ubi_volume *vol)
640 {
641 	dbg_gen("free volume %d", vol->vol_id);
642 
643 	ubi->volumes[vol->vol_id] = NULL;
644 	cdev_del(&vol->cdev);
645 	device_unregister(&vol->dev);
646 }
647 
648 /**
649  * self_check_volume - check volume information.
650  * @ubi: UBI device description object
651  * @vol_id: volume ID
652  *
653  * Returns zero if volume is all right and a a negative error code if not.
654  */
self_check_volume(struct ubi_device * ubi,int vol_id)655 static int self_check_volume(struct ubi_device *ubi, int vol_id)
656 {
657 	int idx = vol_id2idx(ubi, vol_id);
658 	int reserved_pebs, alignment, data_pad, vol_type, name_len, upd_marker;
659 	const struct ubi_volume *vol;
660 	long long n;
661 	const char *name;
662 
663 	spin_lock(&ubi->volumes_lock);
664 	reserved_pebs = be32_to_cpu(ubi->vtbl[vol_id].reserved_pebs);
665 	vol = ubi->volumes[idx];
666 
667 	if (!vol) {
668 		if (reserved_pebs) {
669 			ubi_err(ubi, "no volume info, but volume exists");
670 			goto fail;
671 		}
672 		spin_unlock(&ubi->volumes_lock);
673 		return 0;
674 	}
675 
676 	if (vol->reserved_pebs < 0 || vol->alignment < 0 || vol->data_pad < 0 ||
677 	    vol->name_len < 0) {
678 		ubi_err(ubi, "negative values");
679 		goto fail;
680 	}
681 	if (vol->alignment > ubi->leb_size || vol->alignment == 0) {
682 		ubi_err(ubi, "bad alignment");
683 		goto fail;
684 	}
685 
686 	n = vol->alignment & (ubi->min_io_size - 1);
687 	if (vol->alignment != 1 && n) {
688 		ubi_err(ubi, "alignment is not multiple of min I/O unit");
689 		goto fail;
690 	}
691 
692 	n = ubi->leb_size % vol->alignment;
693 	if (vol->data_pad != n) {
694 		ubi_err(ubi, "bad data_pad, has to be %lld", n);
695 		goto fail;
696 	}
697 
698 	if (vol->vol_type != UBI_DYNAMIC_VOLUME &&
699 	    vol->vol_type != UBI_STATIC_VOLUME) {
700 		ubi_err(ubi, "bad vol_type");
701 		goto fail;
702 	}
703 
704 	if (vol->upd_marker && vol->corrupted) {
705 		ubi_err(ubi, "update marker and corrupted simultaneously");
706 		goto fail;
707 	}
708 
709 	if (vol->reserved_pebs > ubi->good_peb_count) {
710 		ubi_err(ubi, "too large reserved_pebs");
711 		goto fail;
712 	}
713 
714 	n = ubi->leb_size - vol->data_pad;
715 	if (vol->usable_leb_size != ubi->leb_size - vol->data_pad) {
716 		ubi_err(ubi, "bad usable_leb_size, has to be %lld", n);
717 		goto fail;
718 	}
719 
720 	if (vol->name_len > UBI_VOL_NAME_MAX) {
721 		ubi_err(ubi, "too long volume name, max is %d",
722 			UBI_VOL_NAME_MAX);
723 		goto fail;
724 	}
725 
726 	n = strnlen(vol->name, vol->name_len + 1);
727 	if (n != vol->name_len) {
728 		ubi_err(ubi, "bad name_len %lld", n);
729 		goto fail;
730 	}
731 
732 	n = (long long)vol->used_ebs * vol->usable_leb_size;
733 	if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
734 		if (vol->corrupted) {
735 			ubi_err(ubi, "corrupted dynamic volume");
736 			goto fail;
737 		}
738 		if (vol->used_ebs != vol->reserved_pebs) {
739 			ubi_err(ubi, "bad used_ebs");
740 			goto fail;
741 		}
742 		if (vol->last_eb_bytes != vol->usable_leb_size) {
743 			ubi_err(ubi, "bad last_eb_bytes");
744 			goto fail;
745 		}
746 		if (vol->used_bytes != n) {
747 			ubi_err(ubi, "bad used_bytes");
748 			goto fail;
749 		}
750 
751 		if (vol->skip_check) {
752 			ubi_err(ubi, "bad skip_check");
753 			goto fail;
754 		}
755 	} else {
756 		if (vol->used_ebs < 0 || vol->used_ebs > vol->reserved_pebs) {
757 			ubi_err(ubi, "bad used_ebs");
758 			goto fail;
759 		}
760 		if (vol->last_eb_bytes < 0 ||
761 		    vol->last_eb_bytes > vol->usable_leb_size) {
762 			ubi_err(ubi, "bad last_eb_bytes");
763 			goto fail;
764 		}
765 		if (vol->used_bytes < 0 || vol->used_bytes > n ||
766 		    vol->used_bytes < n - vol->usable_leb_size) {
767 			ubi_err(ubi, "bad used_bytes");
768 			goto fail;
769 		}
770 	}
771 
772 	alignment  = be32_to_cpu(ubi->vtbl[vol_id].alignment);
773 	data_pad   = be32_to_cpu(ubi->vtbl[vol_id].data_pad);
774 	name_len   = be16_to_cpu(ubi->vtbl[vol_id].name_len);
775 	upd_marker = ubi->vtbl[vol_id].upd_marker;
776 	name       = &ubi->vtbl[vol_id].name[0];
777 	if (ubi->vtbl[vol_id].vol_type == UBI_VID_DYNAMIC)
778 		vol_type = UBI_DYNAMIC_VOLUME;
779 	else
780 		vol_type = UBI_STATIC_VOLUME;
781 
782 	if (alignment != vol->alignment || data_pad != vol->data_pad ||
783 	    upd_marker != vol->upd_marker || vol_type != vol->vol_type ||
784 	    name_len != vol->name_len || strncmp(name, vol->name, name_len)) {
785 		ubi_err(ubi, "volume info is different");
786 		goto fail;
787 	}
788 
789 	spin_unlock(&ubi->volumes_lock);
790 	return 0;
791 
792 fail:
793 	ubi_err(ubi, "self-check failed for volume %d", vol_id);
794 	if (vol)
795 		ubi_dump_vol_info(vol);
796 	ubi_dump_vtbl_record(&ubi->vtbl[vol_id], vol_id);
797 	dump_stack();
798 	spin_unlock(&ubi->volumes_lock);
799 	return -EINVAL;
800 }
801 
802 /**
803  * self_check_volumes - check information about all volumes.
804  * @ubi: UBI device description object
805  *
806  * Returns zero if volumes are all right and a a negative error code if not.
807  */
self_check_volumes(struct ubi_device * ubi)808 static int self_check_volumes(struct ubi_device *ubi)
809 {
810 	int i, err = 0;
811 
812 	if (!ubi_dbg_chk_gen(ubi))
813 		return 0;
814 
815 	for (i = 0; i < ubi->vtbl_slots; i++) {
816 		err = self_check_volume(ubi, i);
817 		if (err)
818 			break;
819 	}
820 
821 	return err;
822 }
823