vmt.c

  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] || ubi->volumes[vol->vol_id]->is_dead) {
 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
127static struct fwnode_handle *find_volume_fwnode(struct ubi_volume *vol)
128{
129	struct fwnode_handle *fw_vols, *fw_vol;
130	const char *volname;
131	u32 volid;
132
133	fw_vols = device_get_named_child_node(vol->dev.parent->parent, "volumes");
134	if (!fw_vols)
135		return NULL;
136
137	fwnode_for_each_child_node(fw_vols, fw_vol) {
138		if (!fwnode_property_read_string(fw_vol, "volname", &volname) &&
139		    strncmp(volname, vol->name, vol->name_len))
140			continue;
141
142		if (!fwnode_property_read_u32(fw_vol, "volid", &volid) &&
143		    vol->vol_id != volid)
144			continue;
145
146		fwnode_handle_put(fw_vols);
147		return fw_vol;
148	}
149	fwnode_handle_put(fw_vols);
150
151	return NULL;
152}
153
154/**
155 * ubi_create_volume - create volume.
156 * @ubi: UBI device description object
157 * @req: volume creation request
158 *
159 * This function creates volume described by @req. If @req->vol_id id
160 * %UBI_VOL_NUM_AUTO, this function automatically assign ID to the new volume
161 * and saves it in @req->vol_id. Returns zero in case of success and a negative
162 * error code in case of failure. Note, the caller has to have the
163 * @ubi->device_mutex locked.
164 */
165int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req)
166{
167	int i, err, vol_id = req->vol_id;
168	struct ubi_volume *vol;
169	struct ubi_vtbl_record vtbl_rec;
170	struct ubi_eba_table *eba_tbl = NULL;
171
172	if (ubi->ro_mode)
173		return -EROFS;
174
175	vol = kzalloc(sizeof(struct ubi_volume), GFP_KERNEL);
176	if (!vol)
177		return -ENOMEM;
178
179	device_initialize(&vol->dev);
180	vol->dev.release = vol_release;
181	vol->dev.parent = &ubi->dev;
182	vol->dev.class = &ubi_class;
183	vol->dev.groups = volume_dev_groups;
184
185	if (req->flags & UBI_VOL_SKIP_CRC_CHECK_FLG)
186		vol->skip_check = 1;
187
188	spin_lock(&ubi->volumes_lock);
189	if (vol_id == UBI_VOL_NUM_AUTO) {
190		/* Find unused volume ID */
191		dbg_gen("search for vacant volume ID");
192		for (i = 0; i < ubi->vtbl_slots; i++)
193			if (!ubi->volumes[i]) {
194				vol_id = i;
195				break;
196			}
197
198		if (vol_id == UBI_VOL_NUM_AUTO) {
199			ubi_err(ubi, "out of volume IDs");
200			err = -ENFILE;
201			goto out_unlock;
202		}
203		req->vol_id = vol_id;
204	}
205
206	dbg_gen("create device %d, volume %d, %llu bytes, type %d, name %s",
207		ubi->ubi_num, vol_id, (unsigned long long)req->bytes,
208		(int)req->vol_type, req->name);
209
210	/* Ensure that this volume does not exist */
211	err = -EEXIST;
212	if (ubi->volumes[vol_id]) {
213		ubi_err(ubi, "volume %d already exists", vol_id);
214		goto out_unlock;
215	}
216
217	/* Ensure that the name is unique */
218	for (i = 0; i < ubi->vtbl_slots; i++)
219		if (ubi->volumes[i] && !ubi->volumes[i]->is_dead &&
220		    ubi->volumes[i]->name_len == req->name_len &&
221		    !strcmp(ubi->volumes[i]->name, req->name)) {
222			ubi_err(ubi, "volume \"%s\" exists (ID %d)",
223				req->name, i);
224			goto out_unlock;
225		}
226
227	/* Calculate how many eraseblocks are requested */
228	vol->usable_leb_size = ubi->leb_size - ubi->leb_size % req->alignment;
229	vol->reserved_pebs = div_u64(req->bytes + vol->usable_leb_size - 1,
230				     vol->usable_leb_size);
231
232	/* Reserve physical eraseblocks */
233	if (vol->reserved_pebs > ubi->avail_pebs) {
234		ubi_err(ubi, "not enough PEBs, only %d available",
235			ubi->avail_pebs);
236		if (ubi->corr_peb_count)
237			ubi_err(ubi, "%d PEBs are corrupted and not used",
238				ubi->corr_peb_count);
239		err = -ENOSPC;
240		goto out_unlock;
241	}
242	ubi->avail_pebs -= vol->reserved_pebs;
243	ubi->rsvd_pebs += vol->reserved_pebs;
244	spin_unlock(&ubi->volumes_lock);
245
246	vol->vol_id    = vol_id;
247	vol->alignment = req->alignment;
248	vol->data_pad  = ubi->leb_size % vol->alignment;
249	vol->vol_type  = req->vol_type;
250	vol->name_len  = req->name_len;
251	memcpy(vol->name, req->name, vol->name_len);
252	vol->ubi = ubi;
253	device_set_node(&vol->dev, find_volume_fwnode(vol));
254
255	/*
256	 * Finish all pending erases because there may be some LEBs belonging
257	 * to the same volume ID.
258	 */
259	err = ubi_wl_flush(ubi, vol_id, UBI_ALL);
260	if (err)
261		goto out_acc;
262
263	eba_tbl = ubi_eba_create_table(vol, vol->reserved_pebs);
264	if (IS_ERR(eba_tbl)) {
265		err = PTR_ERR(eba_tbl);
266		goto out_acc;
267	}
268
269	ubi_eba_replace_table(vol, eba_tbl);
270
271	if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
272		vol->used_ebs = vol->reserved_pebs;
273		vol->last_eb_bytes = vol->usable_leb_size;
274		vol->used_bytes =
275			(long long)vol->used_ebs * vol->usable_leb_size;
276	} else {
277		vol->used_ebs = div_u64_rem(vol->used_bytes,
278					    vol->usable_leb_size,
279					    &vol->last_eb_bytes);
280		if (vol->last_eb_bytes != 0)
281			vol->used_ebs += 1;
282		else
283			vol->last_eb_bytes = vol->usable_leb_size;
284	}
285
286	/* Make volume "available" before it becomes accessible via sysfs */
287	spin_lock(&ubi->volumes_lock);
288	ubi->volumes[vol_id] = vol;
289	ubi->vol_count += 1;
290	spin_unlock(&ubi->volumes_lock);
291
292	/* Register character device for the volume */
293	cdev_init(&vol->cdev, &ubi_vol_cdev_operations);
294	vol->cdev.owner = THIS_MODULE;
295
296	vol->dev.devt = MKDEV(MAJOR(ubi->cdev.dev), vol_id + 1);
297	dev_set_name(&vol->dev, "%s_%d", ubi->ubi_name, vol->vol_id);
298	err = cdev_device_add(&vol->cdev, &vol->dev);
299	if (err) {
300		ubi_err(ubi, "cannot add device");
301		goto out_mapping;
302	}
303
304	/* Fill volume table record */
305	memset(&vtbl_rec, 0, sizeof(struct ubi_vtbl_record));
306	vtbl_rec.reserved_pebs = cpu_to_be32(vol->reserved_pebs);
307	vtbl_rec.alignment     = cpu_to_be32(vol->alignment);
308	vtbl_rec.data_pad      = cpu_to_be32(vol->data_pad);
309	vtbl_rec.name_len      = cpu_to_be16(vol->name_len);
310	if (vol->vol_type == UBI_DYNAMIC_VOLUME)
311		vtbl_rec.vol_type = UBI_VID_DYNAMIC;
312	else
313		vtbl_rec.vol_type = UBI_VID_STATIC;
314
315	if (vol->skip_check)
316		vtbl_rec.flags |= UBI_VTBL_SKIP_CRC_CHECK_FLG;
317
318	memcpy(vtbl_rec.name, vol->name, vol->name_len);
319
320	err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
321	if (err)
322		goto out_sysfs;
323
324	ubi_volume_notify(ubi, vol, UBI_VOLUME_ADDED);
325	self_check_volumes(ubi);
326	return err;
327
328out_sysfs:
329	/*
330	 * We have registered our device, we should not free the volume
331	 * description object in this function in case of an error - it is
332	 * freed by the release function.
333	 */
334	cdev_device_del(&vol->cdev, &vol->dev);
335out_mapping:
336	spin_lock(&ubi->volumes_lock);
337	ubi->volumes[vol_id] = NULL;
338	ubi->vol_count -= 1;
339	spin_unlock(&ubi->volumes_lock);
340out_acc:
341	spin_lock(&ubi->volumes_lock);
342	ubi->rsvd_pebs -= vol->reserved_pebs;
343	ubi->avail_pebs += vol->reserved_pebs;
344out_unlock:
345	spin_unlock(&ubi->volumes_lock);
346	put_device(&vol->dev);
347	ubi_err(ubi, "cannot create volume %d, error %d", vol_id, err);
348	return err;
349}
350
351/**
352 * ubi_remove_volume - remove volume.
353 * @desc: volume descriptor
354 * @no_vtbl: do not change volume table if not zero
355 *
356 * This function removes volume described by @desc. The volume has to be opened
357 * in "exclusive" mode. Returns zero in case of success and a negative error
358 * code in case of failure. The caller has to have the @ubi->device_mutex
359 * locked.
360 */
361int ubi_remove_volume(struct ubi_volume_desc *desc, int no_vtbl)
362{
363	struct ubi_volume *vol = desc->vol;
364	struct ubi_device *ubi = vol->ubi;
365	int i, err, vol_id = vol->vol_id, reserved_pebs = vol->reserved_pebs;
366
367	dbg_gen("remove device %d, volume %d", ubi->ubi_num, vol_id);
368	ubi_assert(desc->mode == UBI_EXCLUSIVE);
369	ubi_assert(vol == ubi->volumes[vol_id]);
370
371	if (ubi->ro_mode)
372		return -EROFS;
373
374	spin_lock(&ubi->volumes_lock);
375	if (vol->ref_count > 1) {
376		/*
377		 * The volume is busy, probably someone is reading one of its
378		 * sysfs files.
379		 */
380		err = -EBUSY;
381		goto out_unlock;
382	}
383
384	/*
385	 * Mark volume as dead at this point to prevent that anyone
386	 * can take a reference to the volume from now on.
387	 * This is necessary as we have to release the spinlock before
388	 * calling ubi_volume_notify.
389	 */
390	vol->is_dead = true;
391	spin_unlock(&ubi->volumes_lock);
392
393	ubi_volume_notify(ubi, vol, UBI_VOLUME_SHUTDOWN);
394
395	spin_lock(&ubi->volumes_lock);
396	ubi->volumes[vol_id] = NULL;
397	spin_unlock(&ubi->volumes_lock);
398
399	if (!no_vtbl) {
400		err = ubi_change_vtbl_record(ubi, vol_id, NULL);
401		if (err)
402			goto out_err;
403	}
404
405	for (i = 0; i < vol->reserved_pebs; i++) {
406		err = ubi_eba_unmap_leb(ubi, vol, i);
407		if (err)
408			goto out_err;
409	}
410
411	cdev_device_del(&vol->cdev, &vol->dev);
412	put_device(&vol->dev);
413
414	spin_lock(&ubi->volumes_lock);
415	ubi->rsvd_pebs -= reserved_pebs;
416	ubi->avail_pebs += reserved_pebs;
417	ubi_update_reserved(ubi);
418	ubi->vol_count -= 1;
419	spin_unlock(&ubi->volumes_lock);
420
421	ubi_volume_notify(ubi, vol, UBI_VOLUME_REMOVED);
422	if (!no_vtbl)
423		self_check_volumes(ubi);
424
425	return 0;
426
427out_err:
428	ubi_err(ubi, "cannot remove volume %d, error %d", vol_id, err);
429	spin_lock(&ubi->volumes_lock);
430	ubi->volumes[vol_id] = vol;
431out_unlock:
432	spin_unlock(&ubi->volumes_lock);
433	return err;
434}
435
436/**
437 * ubi_resize_volume - re-size volume.
438 * @desc: volume descriptor
439 * @reserved_pebs: new size in physical eraseblocks
440 *
441 * This function re-sizes the volume and returns zero in case of success, and a
442 * negative error code in case of failure. The caller has to have the
443 * @ubi->device_mutex locked.
444 */
445int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs)
446{
447	int i, err, pebs;
448	struct ubi_volume *vol = desc->vol;
449	struct ubi_device *ubi = vol->ubi;
450	struct ubi_vtbl_record vtbl_rec;
451	struct ubi_eba_table *new_eba_tbl = NULL;
452	struct ubi_eba_table *old_eba_tbl = NULL;
453	int vol_id = vol->vol_id;
454
455	if (ubi->ro_mode)
456		return -EROFS;
457
458	dbg_gen("re-size device %d, volume %d to from %d to %d PEBs",
459		ubi->ubi_num, vol_id, vol->reserved_pebs, reserved_pebs);
460
461	if (vol->vol_type == UBI_STATIC_VOLUME &&
462	    reserved_pebs < vol->used_ebs) {
463		ubi_err(ubi, "too small size %d, %d LEBs contain data",
464			reserved_pebs, vol->used_ebs);
465		return -EINVAL;
466	}
467
468	/* If the size is the same, we have nothing to do */
469	if (reserved_pebs == vol->reserved_pebs)
470		return 0;
471
472	new_eba_tbl = ubi_eba_create_table(vol, reserved_pebs);
473	if (IS_ERR(new_eba_tbl))
474		return PTR_ERR(new_eba_tbl);
475
476	spin_lock(&ubi->volumes_lock);
477	if (vol->ref_count > 1) {
478		spin_unlock(&ubi->volumes_lock);
479		err = -EBUSY;
480		goto out_free;
481	}
482	spin_unlock(&ubi->volumes_lock);
483
484	/* Reserve physical eraseblocks */
485	pebs = reserved_pebs - vol->reserved_pebs;
486	if (pebs > 0) {
487		spin_lock(&ubi->volumes_lock);
488		if (pebs > ubi->avail_pebs) {
489			ubi_err(ubi, "not enough PEBs: requested %d, available %d",
490				pebs, ubi->avail_pebs);
491			if (ubi->corr_peb_count)
492				ubi_err(ubi, "%d PEBs are corrupted and not used",
493					ubi->corr_peb_count);
494			spin_unlock(&ubi->volumes_lock);
495			err = -ENOSPC;
496			goto out_free;
497		}
498
499		ubi->avail_pebs -= pebs;
500		ubi->rsvd_pebs += pebs;
501		ubi_eba_copy_table(vol, new_eba_tbl, vol->reserved_pebs);
502		old_eba_tbl = vol->eba_tbl;
503		vol->eba_tbl = new_eba_tbl;
504		vol->reserved_pebs = reserved_pebs;
505		spin_unlock(&ubi->volumes_lock);
506	}
507
508	if (pebs < 0) {
509		for (i = 0; i < -pebs; i++) {
510			err = ubi_eba_unmap_leb(ubi, vol, reserved_pebs + i);
511			if (err)
512				goto out_free;
513		}
514		spin_lock(&ubi->volumes_lock);
515		ubi->rsvd_pebs += pebs;
516		ubi->avail_pebs -= pebs;
517		ubi_update_reserved(ubi);
518		ubi_eba_copy_table(vol, new_eba_tbl, reserved_pebs);
519		old_eba_tbl = vol->eba_tbl;
520		vol->eba_tbl = new_eba_tbl;
521		vol->reserved_pebs = reserved_pebs;
522		spin_unlock(&ubi->volumes_lock);
523	}
524
525	/*
526	 * When we shrink a volume we have to flush all pending (erase) work.
527	 * Otherwise it can happen that upon next attach UBI finds a LEB with
528	 * lnum > highest_lnum and refuses to attach.
529	 */
530	if (pebs < 0) {
531		err = ubi_wl_flush(ubi, vol_id, UBI_ALL);
532		if (err)
533			goto out_acc;
534	}
535
536	/* Change volume table record */
537	vtbl_rec = ubi->vtbl[vol_id];
538	vtbl_rec.reserved_pebs = cpu_to_be32(reserved_pebs);
539	err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
540	if (err)
541		goto out_acc;
542
543	if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
544		vol->used_ebs = reserved_pebs;
545		vol->last_eb_bytes = vol->usable_leb_size;
546		vol->used_bytes =
547			(long long)vol->used_ebs * vol->usable_leb_size;
548	}
549
550	/* destroy old table */
551	ubi_eba_destroy_table(old_eba_tbl);
552	ubi_volume_notify(ubi, vol, UBI_VOLUME_RESIZED);
553	self_check_volumes(ubi);
554	return err;
555
556out_acc:
557	spin_lock(&ubi->volumes_lock);
558	vol->reserved_pebs = reserved_pebs - pebs;
559	ubi->rsvd_pebs -= pebs;
560	ubi->avail_pebs += pebs;
561	if (pebs > 0)
562		ubi_eba_copy_table(vol, old_eba_tbl, vol->reserved_pebs);
563	else
564		ubi_eba_copy_table(vol, old_eba_tbl, reserved_pebs);
565	vol->eba_tbl = old_eba_tbl;
566	spin_unlock(&ubi->volumes_lock);
567out_free:
568	ubi_eba_destroy_table(new_eba_tbl);
569	return err;
570}
571
572/**
573 * ubi_rename_volumes - re-name UBI volumes.
574 * @ubi: UBI device description object
575 * @rename_list: list of &struct ubi_rename_entry objects
576 *
577 * This function re-names or removes volumes specified in the re-name list.
578 * Returns zero in case of success and a negative error code in case of
579 * failure.
580 */
581int ubi_rename_volumes(struct ubi_device *ubi, struct list_head *rename_list)
582{
583	int err;
584	struct ubi_rename_entry *re;
585
586	err = ubi_vtbl_rename_volumes(ubi, rename_list);
587	if (err)
588		return err;
589
590	list_for_each_entry(re, rename_list, list) {
591		if (re->remove) {
592			err = ubi_remove_volume(re->desc, 1);
593			if (err)
594				break;
595		} else {
596			struct ubi_volume *vol = re->desc->vol;
597
598			spin_lock(&ubi->volumes_lock);
599			vol->name_len = re->new_name_len;
600			memcpy(vol->name, re->new_name, re->new_name_len + 1);
601			spin_unlock(&ubi->volumes_lock);
602			ubi_volume_notify(ubi, vol, UBI_VOLUME_RENAMED);
603		}
604	}
605
606	if (!err)
607		self_check_volumes(ubi);
608	return err;
609}
610
611/**
612 * ubi_add_volume - add volume.
613 * @ubi: UBI device description object
614 * @vol: volume description object
615 *
616 * This function adds an existing volume and initializes all its data
617 * structures. Returns zero in case of success and a negative error code in
618 * case of failure.
619 */
620int ubi_add_volume(struct ubi_device *ubi, struct ubi_volume *vol)
621{
622	int err, vol_id = vol->vol_id;
623	dev_t dev;
624
625	dbg_gen("add volume %d", vol_id);
626
627	/* Register character device for the volume */
628	cdev_init(&vol->cdev, &ubi_vol_cdev_operations);
629	vol->cdev.owner = THIS_MODULE;
630	dev = MKDEV(MAJOR(ubi->cdev.dev), vol->vol_id + 1);
631	err = cdev_add(&vol->cdev, dev, 1);
632	if (err) {
633		ubi_err(ubi, "cannot add character device for volume %d, error %d",
634			vol_id, err);
635		vol_release(&vol->dev);
636		return err;
637	}
638
639	vol->dev.release = vol_release;
640	vol->dev.parent = &ubi->dev;
641	vol->dev.devt = dev;
642	vol->dev.class = &ubi_class;
643	vol->dev.groups = volume_dev_groups;
644	dev_set_name(&vol->dev, "%s_%d", ubi->ubi_name, vol->vol_id);
645	device_set_node(&vol->dev, find_volume_fwnode(vol));
646	err = device_register(&vol->dev);
647	if (err) {
648		cdev_del(&vol->cdev);
649		put_device(&vol->dev);
650		return err;
651	}
652
653	self_check_volumes(ubi);
654	return err;
655}
656
657/**
658 * ubi_free_volume - free volume.
659 * @ubi: UBI device description object
660 * @vol: volume description object
661 *
662 * This function frees all resources for volume @vol but does not remove it.
663 * Used only when the UBI device is detached.
664 */
665void ubi_free_volume(struct ubi_device *ubi, struct ubi_volume *vol)
666{
667	dbg_gen("free volume %d", vol->vol_id);
668
669	ubi->volumes[vol->vol_id] = NULL;
670	cdev_del(&vol->cdev);
671	device_unregister(&vol->dev);
672}
673
674/**
675 * self_check_volume - check volume information.
676 * @ubi: UBI device description object
677 * @vol_id: volume ID
678 *
679 * Returns zero if volume is all right and a negative error code if not.
680 */
681static int self_check_volume(struct ubi_device *ubi, int vol_id)
682{
683	int idx = vol_id2idx(ubi, vol_id);
684	int reserved_pebs, alignment, data_pad, vol_type, name_len, upd_marker;
685	const struct ubi_volume *vol;
686	long long n;
687	const char *name;
688
689	spin_lock(&ubi->volumes_lock);
690	reserved_pebs = be32_to_cpu(ubi->vtbl[vol_id].reserved_pebs);
691	vol = ubi->volumes[idx];
692
693	if (!vol) {
694		if (reserved_pebs) {
695			ubi_err(ubi, "no volume info, but volume exists");
696			goto fail;
697		}
698		spin_unlock(&ubi->volumes_lock);
699		return 0;
700	}
701
702	if (vol->reserved_pebs < 0 || vol->alignment < 0 || vol->data_pad < 0 ||
703	    vol->name_len < 0) {
704		ubi_err(ubi, "negative values");
705		goto fail;
706	}
707	if (vol->alignment > ubi->leb_size || vol->alignment == 0) {
708		ubi_err(ubi, "bad alignment");
709		goto fail;
710	}
711
712	n = vol->alignment & (ubi->min_io_size - 1);
713	if (vol->alignment != 1 && n) {
714		ubi_err(ubi, "alignment is not multiple of min I/O unit");
715		goto fail;
716	}
717
718	n = ubi->leb_size % vol->alignment;
719	if (vol->data_pad != n) {
720		ubi_err(ubi, "bad data_pad, has to be %lld", n);
721		goto fail;
722	}
723
724	if (vol->vol_type != UBI_DYNAMIC_VOLUME &&
725	    vol->vol_type != UBI_STATIC_VOLUME) {
726		ubi_err(ubi, "bad vol_type");
727		goto fail;
728	}
729
730	if (vol->upd_marker && vol->corrupted) {
731		ubi_err(ubi, "update marker and corrupted simultaneously");
732		goto fail;
733	}
734
735	if (vol->reserved_pebs > ubi->good_peb_count) {
736		ubi_err(ubi, "too large reserved_pebs");
737		goto fail;
738	}
739
740	n = ubi->leb_size - vol->data_pad;
741	if (vol->usable_leb_size != ubi->leb_size - vol->data_pad) {
742		ubi_err(ubi, "bad usable_leb_size, has to be %lld", n);
743		goto fail;
744	}
745
746	if (vol->name_len > UBI_VOL_NAME_MAX) {
747		ubi_err(ubi, "too long volume name, max is %d",
748			UBI_VOL_NAME_MAX);
749		goto fail;
750	}
751
752	n = strnlen(vol->name, vol->name_len + 1);
753	if (n != vol->name_len) {
754		ubi_err(ubi, "bad name_len %lld", n);
755		goto fail;
756	}
757
758	n = (long long)vol->used_ebs * vol->usable_leb_size;
759	if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
760		if (vol->corrupted) {
761			ubi_err(ubi, "corrupted dynamic volume");
762			goto fail;
763		}
764		if (vol->used_ebs != vol->reserved_pebs) {
765			ubi_err(ubi, "bad used_ebs");
766			goto fail;
767		}
768		if (vol->last_eb_bytes != vol->usable_leb_size) {
769			ubi_err(ubi, "bad last_eb_bytes");
770			goto fail;
771		}
772		if (vol->used_bytes != n) {
773			ubi_err(ubi, "bad used_bytes");
774			goto fail;
775		}
776
777		if (vol->skip_check) {
778			ubi_err(ubi, "bad skip_check");
779			goto fail;
780		}
781	} else {
782		if (vol->used_ebs < 0 || vol->used_ebs > vol->reserved_pebs) {
783			ubi_err(ubi, "bad used_ebs");
784			goto fail;
785		}
786		if (vol->last_eb_bytes < 0 ||
787		    vol->last_eb_bytes > vol->usable_leb_size) {
788			ubi_err(ubi, "bad last_eb_bytes");
789			goto fail;
790		}
791		if (vol->used_bytes < 0 || vol->used_bytes > n ||
792		    vol->used_bytes < n - vol->usable_leb_size) {
793			ubi_err(ubi, "bad used_bytes");
794			goto fail;
795		}
796	}
797
798	alignment  = be32_to_cpu(ubi->vtbl[vol_id].alignment);
799	data_pad   = be32_to_cpu(ubi->vtbl[vol_id].data_pad);
800	name_len   = be16_to_cpu(ubi->vtbl[vol_id].name_len);
801	upd_marker = ubi->vtbl[vol_id].upd_marker;
802	name       = &ubi->vtbl[vol_id].name[0];
803	if (ubi->vtbl[vol_id].vol_type == UBI_VID_DYNAMIC)
804		vol_type = UBI_DYNAMIC_VOLUME;
805	else
806		vol_type = UBI_STATIC_VOLUME;
807
808	if (alignment != vol->alignment || data_pad != vol->data_pad ||
809	    upd_marker != vol->upd_marker || vol_type != vol->vol_type ||
810	    name_len != vol->name_len || strncmp(name, vol->name, name_len)) {
811		ubi_err(ubi, "volume info is different");
812		goto fail;
813	}
814
815	spin_unlock(&ubi->volumes_lock);
816	return 0;
817
818fail:
819	ubi_err(ubi, "self-check failed for volume %d", vol_id);
820	if (vol)
821		ubi_dump_vol_info(vol);
822	ubi_dump_vtbl_record(&ubi->vtbl[vol_id], vol_id);
823	dump_stack();
824	spin_unlock(&ubi->volumes_lock);
825	return -EINVAL;
826}
827
828/**
829 * self_check_volumes - check information about all volumes.
830 * @ubi: UBI device description object
831 *
832 * Returns zero if volumes are all right and a negative error code if not.
833 */
834static int self_check_volumes(struct ubi_device *ubi)
835{
836	int i, err = 0;
837
838	if (!ubi_dbg_chk_gen(ubi))
839		return 0;
840
841	for (i = 0; i < ubi->vtbl_slots; i++) {
842		err = self_check_volume(ubi, i);
843		if (err)
844			break;
845	}
846
847	return err;
848}