drivers/mtd/ubi/vmt.c

   1 /*
   2  * Copyright (c) International Business Machines Corp., 2006
   3  *
   4  * SPDX-License-Identifier:     GPL-2.0+
   5  *
   6  * Author: Artem Bityutskiy (Битюцкий Артём)
   7  */
   8
   9 /*
  10  * This file contains implementation of volume creation, deletion, updating and
  11  * resizing.
  12  */
  13
  14 #ifdef UBI_LINUX
  15 #include <linux/err.h>
  16 #include <asm/div64.h>
  17 #endif
  18
  19 #include <ubi_uboot.h>
  20 #include "ubi.h"
  21
  22 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
  23 static void paranoid_check_volumes(struct ubi_device *ubi);
  24 #else
  25 #define paranoid_check_volumes(ubi)
  26 #endif
  27
  28 #ifdef UBI_LINUX
  29 static ssize_t vol_attribute_show(struct device *dev,
  30                                   struct device_attribute *attr, char *buf);
  31
  32 /* Device attributes corresponding to files in '/<sysfs>/class/ubi/ubiX_Y' */
  33 static struct device_attribute attr_vol_reserved_ebs =
  34         __ATTR(reserved_ebs, S_IRUGO, vol_attribute_show, NULL);
  35 static struct device_attribute attr_vol_type =
  36         __ATTR(type, S_IRUGO, vol_attribute_show, NULL);
  37 static struct device_attribute attr_vol_name =
  38         __ATTR(name, S_IRUGO, vol_attribute_show, NULL);
  39 static struct device_attribute attr_vol_corrupted =
  40         __ATTR(corrupted, S_IRUGO, vol_attribute_show, NULL);
  41 static struct device_attribute attr_vol_alignment =
  42         __ATTR(alignment, S_IRUGO, vol_attribute_show, NULL);
  43 static struct device_attribute attr_vol_usable_eb_size =
  44         __ATTR(usable_eb_size, S_IRUGO, vol_attribute_show, NULL);
  45 static struct device_attribute attr_vol_data_bytes =
  46         __ATTR(data_bytes, S_IRUGO, vol_attribute_show, NULL);
  47 static struct device_attribute attr_vol_upd_marker =
  48         __ATTR(upd_marker, S_IRUGO, vol_attribute_show, NULL);
  49
  50 /*
  51  * "Show" method for files in '/<sysfs>/class/ubi/ubiX_Y/'.
  52  *
  53  * Consider a situation:
  54  * A. process 1 opens a sysfs file related to volume Y, say
  55  *    /<sysfs>/class/ubi/ubiX_Y/reserved_ebs;
  56  * B. process 2 removes volume Y;
  57  * C. process 1 starts reading the /<sysfs>/class/ubi/ubiX_Y/reserved_ebs file;
  58  *
  59  * In this situation, this function will return %-ENODEV because it will find
  60  * out that the volume was removed from the @ubi->volumes array.
  61  */
  62 static ssize_t vol_attribute_show(struct device *dev,
  63                                   struct device_attribute *attr, char *buf)
  64 {
  65         int ret;
  66         struct ubi_volume *vol = container_of(dev, struct ubi_volume, dev);
  67         struct ubi_device *ubi;
  68
  69         ubi = ubi_get_device(vol->ubi->ubi_num);
  70         if (!ubi)
  71                 return -ENODEV;
  72
  73         spin_lock(&ubi->volumes_lock);
  74         if (!ubi->volumes[vol->vol_id]) {
  75                 spin_unlock(&ubi->volumes_lock);
  76                 ubi_put_device(ubi);
  77                 return -ENODEV;
  78         }
  79         /* Take a reference to prevent volume removal */
  80         vol->ref_count += 1;
  81         spin_unlock(&ubi->volumes_lock);
  82
  83         if (attr == &attr_vol_reserved_ebs)
  84                 ret = sprintf(buf, "%d\n", vol->reserved_pebs);
  85         else if (attr == &attr_vol_type) {
  86                 const char *tp;
  87
  88                 if (vol->vol_type == UBI_DYNAMIC_VOLUME)
  89                         tp = "dynamic";
  90                 else
  91                         tp = "static";
  92                 ret = sprintf(buf, "%s\n", tp);
  93         } else if (attr == &attr_vol_name)
  94                 ret = sprintf(buf, "%s\n", vol->name);
  95         else if (attr == &attr_vol_corrupted)
  96                 ret = sprintf(buf, "%d\n", vol->corrupted);
  97         else if (attr == &attr_vol_alignment)
  98                 ret = sprintf(buf, "%d\n", vol->alignment);
  99         else if (attr == &attr_vol_usable_eb_size)
 100                 ret = sprintf(buf, "%d\n", vol->usable_leb_size);
 101         else if (attr == &attr_vol_data_bytes)
 102                 ret = sprintf(buf, "%lld\n", vol->used_bytes);
 103         else if (attr == &attr_vol_upd_marker)
 104                 ret = sprintf(buf, "%d\n", vol->upd_marker);
 105         else
 106                 /* This must be a bug */
 107                 ret = -EINVAL;
 108
 109         /* We've done the operation, drop volume and UBI device references */
 110         spin_lock(&ubi->volumes_lock);
 111         vol->ref_count -= 1;
 112         ubi_assert(vol->ref_count >= 0);
 113         spin_unlock(&ubi->volumes_lock);
 114         ubi_put_device(ubi);
 115         return ret;
 116 }
 117 #endif
 118
 119 /* Release method for volume devices */
 120 static void vol_release(struct device *dev)
 121 {
 122         struct ubi_volume *vol = container_of(dev, struct ubi_volume, dev);
 123
 124         kfree(vol);
 125 }
 126
 127 #ifdef UBI_LINUX
 128 /**
 129  * volume_sysfs_init - initialize sysfs for new volume.
 130  * @ubi: UBI device description object
 131  * @vol: volume description object
 132  *
 133  * This function returns zero in case of success and a negative error code in
 134  * case of failure.
 135  *
 136  * Note, this function does not free allocated resources in case of failure -
 137  * the caller does it. This is because this would cause release() here and the
 138  * caller would oops.
 139  */
 140 static int volume_sysfs_init(struct ubi_device *ubi, struct ubi_volume *vol)
 141 {
 142         int err;
 143
 144         err = device_create_file(&vol->dev, &attr_vol_reserved_ebs);
 145         if (err)
 146                 return err;
 147         err = device_create_file(&vol->dev, &attr_vol_type);
 148         if (err)
 149                 return err;
 150         err = device_create_file(&vol->dev, &attr_vol_name);
 151         if (err)
 152                 return err;
 153         err = device_create_file(&vol->dev, &attr_vol_corrupted);
 154         if (err)
 155                 return err;
 156         err = device_create_file(&vol->dev, &attr_vol_alignment);
 157         if (err)
 158                 return err;
 159         err = device_create_file(&vol->dev, &attr_vol_usable_eb_size);
 160         if (err)
 161                 return err;
 162         err = device_create_file(&vol->dev, &attr_vol_data_bytes);
 163         if (err)
 164                 return err;
 165         err = device_create_file(&vol->dev, &attr_vol_upd_marker);
 166         return err;
 167 }
 168
 169 /**
 170  * volume_sysfs_close - close sysfs for a volume.
 171  * @vol: volume description object
 172  */
 173 static void volume_sysfs_close(struct ubi_volume *vol)
 174 {
 175         device_remove_file(&vol->dev, &attr_vol_upd_marker);
 176         device_remove_file(&vol->dev, &attr_vol_data_bytes);
 177         device_remove_file(&vol->dev, &attr_vol_usable_eb_size);
 178         device_remove_file(&vol->dev, &attr_vol_alignment);
 179         device_remove_file(&vol->dev, &attr_vol_corrupted);
 180         device_remove_file(&vol->dev, &attr_vol_name);
 181         device_remove_file(&vol->dev, &attr_vol_type);
 182         device_remove_file(&vol->dev, &attr_vol_reserved_ebs);
 183         device_unregister(&vol->dev);
 184 }
 185 #endif
 186
 187 /**
 188  * ubi_create_volume - create volume.
 189  * @ubi: UBI device description object
 190  * @req: volume creation request
 191  *
 192  * This function creates volume described by @req. If @req->vol_id id
 193  * %UBI_VOL_NUM_AUTO, this function automatically assign ID to the new volume
 194  * and saves it in @req->vol_id. Returns zero in case of success and a negative
 195  * error code in case of failure. Note, the caller has to have the
 196  * @ubi->volumes_mutex locked.
 197  */
 198 int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req)
 199 {
 200         int i, err, vol_id = req->vol_id, dont_free = 0;
 201         struct ubi_volume *vol;
 202         struct ubi_vtbl_record vtbl_rec;
 203         uint64_t bytes;
 204         dev_t dev;
 205
 206         if (ubi->ro_mode)
 207                 return -EROFS;
 208
 209         vol = kzalloc(sizeof(struct ubi_volume), GFP_KERNEL);
 210         if (!vol)
 211                 return -ENOMEM;
 212
 213         spin_lock(&ubi->volumes_lock);
 214         if (vol_id == UBI_VOL_NUM_AUTO) {
 215                 /* Find unused volume ID */
 216                 dbg_msg("search for vacant volume ID");
 217                 for (i = 0; i < ubi->vtbl_slots; i++)
 218                         if (!ubi->volumes[i]) {
 219                                 vol_id = i;
 220                                 break;
 221                         }
 222
 223                 if (vol_id == UBI_VOL_NUM_AUTO) {
 224                         dbg_err("out of volume IDs");
 225                         err = -ENFILE;
 226                         goto out_unlock;
 227                 }
 228                 req->vol_id = vol_id;
 229         }
 230
 231         dbg_msg("volume ID %d, %llu bytes, type %d, name %s",
 232                 vol_id, (unsigned long long)req->bytes,
 233                 (int)req->vol_type, req->name);
 234
 235         /* Ensure that this volume does not exist */
 236         err = -EEXIST;
 237         if (ubi->volumes[vol_id]) {
 238                 dbg_err("volume %d already exists", vol_id);
 239                 goto out_unlock;
 240         }
 241
 242         /* Ensure that the name is unique */
 243         for (i = 0; i < ubi->vtbl_slots; i++)
 244                 if (ubi->volumes[i] &&
 245                     ubi->volumes[i]->name_len == req->name_len &&
 246                     !strcmp(ubi->volumes[i]->name, req->name)) {
 247                         dbg_err("volume \"%s\" exists (ID %d)", req->name, i);
 248                         goto out_unlock;
 249                 }
 250
 251         /* Calculate how many eraseblocks are requested */
 252         vol->usable_leb_size = ubi->leb_size - ubi->leb_size % req->alignment;
 253         bytes = req->bytes;
 254         if (do_div(bytes, vol->usable_leb_size))
 255                 vol->reserved_pebs = 1;
 256         vol->reserved_pebs += bytes;
 257
 258         /* Reserve physical eraseblocks */
 259         if (vol->reserved_pebs > ubi->avail_pebs) {
 260                 dbg_err("not enough PEBs, only %d available", ubi->avail_pebs);
 261                 err = -ENOSPC;
 262                 goto out_unlock;
 263         }
 264         ubi->avail_pebs -= vol->reserved_pebs;
 265         ubi->rsvd_pebs += vol->reserved_pebs;
 266         spin_unlock(&ubi->volumes_lock);
 267
 268         vol->vol_id    = vol_id;
 269         vol->alignment = req->alignment;
 270         vol->data_pad  = ubi->leb_size % vol->alignment;
 271         vol->vol_type  = req->vol_type;
 272         vol->name_len  = req->name_len;
 273         memcpy(vol->name, req->name, vol->name_len + 1);
 274         vol->ubi = ubi;
 275
 276         /*
 277          * Finish all pending erases because there may be some LEBs belonging
 278          * to the same volume ID.
 279          */
 280         err = ubi_wl_flush(ubi);
 281         if (err)
 282                 goto out_acc;
 283
 284         vol->eba_tbl = kmalloc(vol->reserved_pebs * sizeof(int), GFP_KERNEL);
 285         if (!vol->eba_tbl) {
 286                 err = -ENOMEM;
 287                 goto out_acc;
 288         }
 289
 290         for (i = 0; i < vol->reserved_pebs; i++)
 291                 vol->eba_tbl[i] = UBI_LEB_UNMAPPED;
 292
 293         if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
 294                 vol->used_ebs = vol->reserved_pebs;
 295                 vol->last_eb_bytes = vol->usable_leb_size;
 296                 vol->used_bytes =
 297                         (long long)vol->used_ebs * vol->usable_leb_size;
 298         } else {
 299                 bytes = vol->used_bytes;
 300                 vol->last_eb_bytes = do_div(bytes, vol->usable_leb_size);
 301                 vol->used_ebs = bytes;
 302                 if (vol->last_eb_bytes)
 303                         vol->used_ebs += 1;
 304                 else
 305                         vol->last_eb_bytes = vol->usable_leb_size;
 306         }
 307
 308         /* Register character device for the volume */
 309         cdev_init(&vol->cdev, &ubi_vol_cdev_operations);
 310         vol->cdev.owner = THIS_MODULE;
 311         dev = MKDEV(MAJOR(ubi->cdev.dev), vol_id + 1);
 312         err = cdev_add(&vol->cdev, dev, 1);
 313         if (err) {
 314                 ubi_err("cannot add character device");
 315                 goto out_mapping;
 316         }
 317
 318         err = ubi_create_gluebi(ubi, vol);
 319         if (err)
 320                 goto out_cdev;
 321
 322         vol->dev.release = vol_release;
 323         vol->dev.parent = &ubi->dev;
 324         vol->dev.devt = dev;
 325         vol->dev.class = ubi_class;
 326
 327         sprintf(&vol->dev.bus_id[0], "%s_%d", ubi->ubi_name, vol->vol_id);
 328         err = device_register(&vol->dev);
 329         if (err) {
 330                 ubi_err("cannot register device");
 331                 goto out_gluebi;
 332         }
 333
 334         err = volume_sysfs_init(ubi, vol);
 335         if (err)
 336                 goto out_sysfs;
 337
 338         /* Fill volume table record */
 339         memset(&vtbl_rec, 0, sizeof(struct ubi_vtbl_record));
 340         vtbl_rec.reserved_pebs = cpu_to_be32(vol->reserved_pebs);
 341         vtbl_rec.alignment     = cpu_to_be32(vol->alignment);
 342         vtbl_rec.data_pad      = cpu_to_be32(vol->data_pad);
 343         vtbl_rec.name_len      = cpu_to_be16(vol->name_len);
 344         if (vol->vol_type == UBI_DYNAMIC_VOLUME)
 345                 vtbl_rec.vol_type = UBI_VID_DYNAMIC;
 346         else
 347                 vtbl_rec.vol_type = UBI_VID_STATIC;
 348         memcpy(vtbl_rec.name, vol->name, vol->name_len + 1);
 349
 350         err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
 351         if (err)
 352                 goto out_sysfs;
 353
 354         spin_lock(&ubi->volumes_lock);
 355         ubi->volumes[vol_id] = vol;
 356         ubi->vol_count += 1;
 357         spin_unlock(&ubi->volumes_lock);
 358
 359         paranoid_check_volumes(ubi);
 360         return 0;
 361
 362 out_sysfs:
 363         /*
 364          * We have registered our device, we should not free the volume*
 365          * description object in this function in case of an error - it is
 366          * freed by the release function.
 367          *
 368          * Get device reference to prevent the release function from being
 369          * called just after sysfs has been closed.
 370          */
 371         dont_free = 1;
 372         get_device(&vol->dev);
 373         volume_sysfs_close(vol);
 374 out_gluebi:
 375         if (ubi_destroy_gluebi(vol))
 376                 dbg_err("cannot destroy gluebi for volume %d:%d",
 377                         ubi->ubi_num, vol_id);
 378 out_cdev:
 379         cdev_del(&vol->cdev);
 380 out_mapping:
 381         kfree(vol->eba_tbl);
 382 out_acc:
 383         spin_lock(&ubi->volumes_lock);
 384         ubi->rsvd_pebs -= vol->reserved_pebs;
 385         ubi->avail_pebs += vol->reserved_pebs;
 386 out_unlock:
 387         spin_unlock(&ubi->volumes_lock);
 388         if (dont_free)
 389                 put_device(&vol->dev);
 390         else
 391                 kfree(vol);
 392         ubi_err("cannot create volume %d, error %d", vol_id, err);
 393         return err;
 394 }
 395
 396 /**
 397  * ubi_remove_volume - remove volume.
 398  * @desc: volume descriptor
 399  *
 400  * This function removes volume described by @desc. The volume has to be opened
 401  * in "exclusive" mode. Returns zero in case of success and a negative error
 402  * code in case of failure. The caller has to have the @ubi->volumes_mutex
 403  * locked.
 404  */
 405 int ubi_remove_volume(struct ubi_volume_desc *desc)
 406 {
 407         struct ubi_volume *vol = desc->vol;
 408         struct ubi_device *ubi = vol->ubi;
 409         int i, err, vol_id = vol->vol_id, reserved_pebs = vol->reserved_pebs;
 410
 411         dbg_msg("remove UBI volume %d", vol_id);
 412         ubi_assert(desc->mode == UBI_EXCLUSIVE);
 413         ubi_assert(vol == ubi->volumes[vol_id]);
 414
 415         if (ubi->ro_mode)
 416                 return -EROFS;
 417
 418         spin_lock(&ubi->volumes_lock);
 419         if (vol->ref_count > 1) {
 420                 /*
 421                  * The volume is busy, probably someone is reading one of its
 422                  * sysfs files.
 423                  */
 424                 err = -EBUSY;
 425                 goto out_unlock;
 426         }
 427         ubi->volumes[vol_id] = NULL;
 428         spin_unlock(&ubi->volumes_lock);
 429
 430         err = ubi_destroy_gluebi(vol);
 431         if (err)
 432                 goto out_err;
 433
 434         err = ubi_change_vtbl_record(ubi, vol_id, NULL);
 435         if (err)
 436                 goto out_err;
 437
 438         for (i = 0; i < vol->reserved_pebs; i++) {
 439                 err = ubi_eba_unmap_leb(ubi, vol, i);
 440                 if (err)
 441                         goto out_err;
 442         }
 443
 444         kfree(vol->eba_tbl);
 445         vol->eba_tbl = NULL;
 446         cdev_del(&vol->cdev);
 447         volume_sysfs_close(vol);
 448
 449         spin_lock(&ubi->volumes_lock);
 450         ubi->rsvd_pebs -= reserved_pebs;
 451         ubi->avail_pebs += reserved_pebs;
 452         i = ubi->beb_rsvd_level - ubi->beb_rsvd_pebs;
 453         if (i > 0) {
 454                 i = ubi->avail_pebs >= i ? i : ubi->avail_pebs;
 455                 ubi->avail_pebs -= i;
 456                 ubi->rsvd_pebs += i;
 457                 ubi->beb_rsvd_pebs += i;
 458                 if (i > 0)
 459                         ubi_msg("reserve more %d PEBs", i);
 460         }
 461         ubi->vol_count -= 1;
 462         spin_unlock(&ubi->volumes_lock);
 463
 464         paranoid_check_volumes(ubi);
 465         return 0;
 466
 467 out_err:
 468         ubi_err("cannot remove volume %d, error %d", vol_id, err);
 469         spin_lock(&ubi->volumes_lock);
 470         ubi->volumes[vol_id] = vol;
 471 out_unlock:
 472         spin_unlock(&ubi->volumes_lock);
 473         return err;
 474 }
 475
 476 /**
 477  * ubi_resize_volume - re-size volume.
 478  * @desc: volume descriptor
 479  * @reserved_pebs: new size in physical eraseblocks
 480  *
 481  * This function re-sizes the volume and returns zero in case of success, and a
 482  * negative error code in case of failure. The caller has to have the
 483  * @ubi->volumes_mutex locked.
 484  */
 485 int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs)
 486 {
 487         int i, err, pebs, *new_mapping;
 488         struct ubi_volume *vol = desc->vol;
 489         struct ubi_device *ubi = vol->ubi;
 490         struct ubi_vtbl_record vtbl_rec;
 491         int vol_id = vol->vol_id;
 492
 493         if (ubi->ro_mode)
 494                 return -EROFS;
 495
 496         dbg_msg("re-size volume %d to from %d to %d PEBs",
 497                 vol_id, vol->reserved_pebs, reserved_pebs);
 498
 499         if (vol->vol_type == UBI_STATIC_VOLUME &&
 500             reserved_pebs < vol->used_ebs) {
 501                 dbg_err("too small size %d, %d LEBs contain data",
 502                         reserved_pebs, vol->used_ebs);
 503                 return -EINVAL;
 504         }
 505
 506         /* If the size is the same, we have nothing to do */
 507         if (reserved_pebs == vol->reserved_pebs)
 508                 return 0;
 509
 510         new_mapping = kmalloc(reserved_pebs * sizeof(int), GFP_KERNEL);
 511         if (!new_mapping)
 512                 return -ENOMEM;
 513
 514         for (i = 0; i < reserved_pebs; i++)
 515                 new_mapping[i] = UBI_LEB_UNMAPPED;
 516
 517         spin_lock(&ubi->volumes_lock);
 518         if (vol->ref_count > 1) {
 519                 spin_unlock(&ubi->volumes_lock);
 520                 err = -EBUSY;
 521                 goto out_free;
 522         }
 523         spin_unlock(&ubi->volumes_lock);
 524
 525         /* Reserve physical eraseblocks */
 526         pebs = reserved_pebs - vol->reserved_pebs;
 527         if (pebs > 0) {
 528                 spin_lock(&ubi->volumes_lock);
 529                 if (pebs > ubi->avail_pebs) {
 530                         dbg_err("not enough PEBs: requested %d, available %d",
 531                                 pebs, ubi->avail_pebs);
 532                         spin_unlock(&ubi->volumes_lock);
 533                         err = -ENOSPC;
 534                         goto out_free;
 535                 }
 536                 ubi->avail_pebs -= pebs;
 537                 ubi->rsvd_pebs += pebs;
 538                 for (i = 0; i < vol->reserved_pebs; i++)
 539                         new_mapping[i] = vol->eba_tbl[i];
 540                 kfree(vol->eba_tbl);
 541                 vol->eba_tbl = new_mapping;
 542                 spin_unlock(&ubi->volumes_lock);
 543         }
 544
 545         /* Change volume table record */
 546         memcpy(&vtbl_rec, &ubi->vtbl[vol_id], sizeof(struct ubi_vtbl_record));
 547         vtbl_rec.reserved_pebs = cpu_to_be32(reserved_pebs);
 548         err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
 549         if (err)
 550                 goto out_acc;
 551
 552         if (pebs < 0) {
 553                 for (i = 0; i < -pebs; i++) {
 554                         err = ubi_eba_unmap_leb(ubi, vol, reserved_pebs + i);
 555                         if (err)
 556                                 goto out_acc;
 557                 }
 558                 spin_lock(&ubi->volumes_lock);
 559                 ubi->rsvd_pebs += pebs;
 560                 ubi->avail_pebs -= pebs;
 561                 pebs = ubi->beb_rsvd_level - ubi->beb_rsvd_pebs;
 562                 if (pebs > 0) {
 563                         pebs = ubi->avail_pebs >= pebs ? pebs : ubi->avail_pebs;
 564                         ubi->avail_pebs -= pebs;
 565                         ubi->rsvd_pebs += pebs;
 566                         ubi->beb_rsvd_pebs += pebs;
 567                         if (pebs > 0)
 568                                 ubi_msg("reserve more %d PEBs", pebs);
 569                 }
 570                 for (i = 0; i < reserved_pebs; i++)
 571                         new_mapping[i] = vol->eba_tbl[i];
 572                 kfree(vol->eba_tbl);
 573                 vol->eba_tbl = new_mapping;
 574                 spin_unlock(&ubi->volumes_lock);
 575         }
 576
 577         vol->reserved_pebs = reserved_pebs;
 578         if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
 579                 vol->used_ebs = reserved_pebs;
 580                 vol->last_eb_bytes = vol->usable_leb_size;
 581                 vol->used_bytes =
 582                         (long long)vol->used_ebs * vol->usable_leb_size;
 583         }
 584
 585         paranoid_check_volumes(ubi);
 586         return 0;
 587
 588 out_acc:
 589         if (pebs > 0) {
 590                 spin_lock(&ubi->volumes_lock);
 591                 ubi->rsvd_pebs -= pebs;
 592                 ubi->avail_pebs += pebs;
 593                 spin_unlock(&ubi->volumes_lock);
 594         }
 595 out_free:
 596         kfree(new_mapping);
 597         return err;
 598 }
 599
 600 /**
 601  * ubi_add_volume - add volume.
 602  * @ubi: UBI device description object
 603  * @vol: volume description object
 604  *
 605  * This function adds an existing volume and initializes all its data
 606  * structures. Returns zero in case of success and a negative error code in
 607  * case of failure.
 608  */
 609 int ubi_add_volume(struct ubi_device *ubi, struct ubi_volume *vol)
 610 {
 611         int err, vol_id = vol->vol_id;
 612         dev_t dev;
 613
 614         dbg_msg("add volume %d", vol_id);
 615         ubi_dbg_dump_vol_info(vol);
 616
 617         /* Register character device for the volume */
 618         cdev_init(&vol->cdev, &ubi_vol_cdev_operations);
 619         vol->cdev.owner = THIS_MODULE;
 620         dev = MKDEV(MAJOR(ubi->cdev.dev), vol->vol_id + 1);
 621         err = cdev_add(&vol->cdev, dev, 1);
 622         if (err) {
 623                 ubi_err("cannot add character device for volume %d, error %d",
 624                         vol_id, err);
 625                 return err;
 626         }
 627
 628         err = ubi_create_gluebi(ubi, vol);
 629         if (err)
 630                 goto out_cdev;
 631
 632         vol->dev.release = vol_release;
 633         vol->dev.parent = &ubi->dev;
 634         vol->dev.devt = dev;
 635         vol->dev.class = ubi_class;
 636         sprintf(&vol->dev.bus_id[0], "%s_%d", ubi->ubi_name, vol->vol_id);
 637         err = device_register(&vol->dev);
 638         if (err)
 639                 goto out_gluebi;
 640
 641         err = volume_sysfs_init(ubi, vol);
 642         if (err) {
 643                 cdev_del(&vol->cdev);
 644                 err = ubi_destroy_gluebi(vol);
 645                 volume_sysfs_close(vol);
 646                 return err;
 647         }
 648
 649         paranoid_check_volumes(ubi);
 650         return 0;
 651
 652 out_gluebi:
 653         err = ubi_destroy_gluebi(vol);
 654 out_cdev:
 655         cdev_del(&vol->cdev);
 656         return err;
 657 }
 658
 659 /**
 660  * ubi_free_volume - free volume.
 661  * @ubi: UBI device description object
 662  * @vol: volume description object
 663  *
 664  * This function frees all resources for volume @vol but does not remove it.
 665  * Used only when the UBI device is detached.
 666  */
 667 void ubi_free_volume(struct ubi_device *ubi, struct ubi_volume *vol)
 668 {
 669         dbg_msg("free volume %d", vol->vol_id);
 670
 671         ubi->volumes[vol->vol_id] = NULL;
 672         ubi_destroy_gluebi(vol);
 673         cdev_del(&vol->cdev);
 674         volume_sysfs_close(vol);
 675 }
 676
 677 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
 678
 679 /**
 680  * paranoid_check_volume - check volume information.
 681  * @ubi: UBI device description object
 682  * @vol_id: volume ID
 683  */
 684 static void paranoid_check_volume(struct ubi_device *ubi, int vol_id)
 685 {
 686         int idx = vol_id2idx(ubi, vol_id);
 687         int reserved_pebs, alignment, data_pad, vol_type, name_len, upd_marker;
 688         const struct ubi_volume *vol;
 689         long long n;
 690         const char *name;
 691
 692         spin_lock(&ubi->volumes_lock);
 693         reserved_pebs = be32_to_cpu(ubi->vtbl[vol_id].reserved_pebs);
 694         vol = ubi->volumes[idx];
 695
 696         if (!vol) {
 697                 if (reserved_pebs) {
 698                         ubi_err("no volume info, but volume exists");
 699                         goto fail;
 700                 }
 701                 spin_unlock(&ubi->volumes_lock);
 702                 return;
 703         }
 704
 705         if (vol->exclusive) {
 706                 /*
 707                  * The volume may be being created at the moment, do not check
 708                  * it (e.g., it may be in the middle of ubi_create_volume().
 709                  */
 710                 spin_unlock(&ubi->volumes_lock);
 711                 return;
 712         }
 713
 714         if (vol->reserved_pebs < 0 || vol->alignment < 0 || vol->data_pad < 0 ||
 715             vol->name_len < 0) {
 716                 ubi_err("negative values");
 717                 goto fail;
 718         }
 719         if (vol->alignment > ubi->leb_size || vol->alignment == 0) {
 720                 ubi_err("bad alignment");
 721                 goto fail;
 722         }
 723
 724         n = vol->alignment & (ubi->min_io_size - 1);
 725         if (vol->alignment != 1 && n) {
 726                 ubi_err("alignment is not multiple of min I/O unit");
 727                 goto fail;
 728         }
 729
 730         n = ubi->leb_size % vol->alignment;
 731         if (vol->data_pad != n) {
 732                 ubi_err("bad data_pad, has to be %lld", n);
 733                 goto fail;
 734         }
 735
 736         if (vol->vol_type != UBI_DYNAMIC_VOLUME &&
 737             vol->vol_type != UBI_STATIC_VOLUME) {
 738                 ubi_err("bad vol_type");
 739                 goto fail;
 740         }
 741
 742         if (vol->upd_marker && vol->corrupted) {
 743                 dbg_err("update marker and corrupted simultaneously");
 744                 goto fail;
 745         }
 746
 747         if (vol->reserved_pebs > ubi->good_peb_count) {
 748                 ubi_err("too large reserved_pebs");
 749                 goto fail;
 750         }
 751
 752         n = ubi->leb_size - vol->data_pad;
 753         if (vol->usable_leb_size != ubi->leb_size - vol->data_pad) {
 754                 ubi_err("bad usable_leb_size, has to be %lld", n);
 755                 goto fail;
 756         }
 757
 758         if (vol->name_len > UBI_VOL_NAME_MAX) {
 759                 ubi_err("too long volume name, max is %d", UBI_VOL_NAME_MAX);
 760                 goto fail;
 761         }
 762
 763         if (!vol->name) {
 764                 ubi_err("NULL volume name");
 765                 goto fail;
 766         }
 767
 768         n = strnlen(vol->name, vol->name_len + 1);
 769         if (n != vol->name_len) {
 770                 ubi_err("bad name_len %lld", n);
 771                 goto fail;
 772         }
 773
 774         n = (long long)vol->used_ebs * vol->usable_leb_size;
 775         if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
 776                 if (vol->corrupted) {
 777                         ubi_err("corrupted dynamic volume");
 778                         goto fail;
 779                 }
 780                 if (vol->used_ebs != vol->reserved_pebs) {
 781                         ubi_err("bad used_ebs");
 782                         goto fail;
 783                 }
 784                 if (vol->last_eb_bytes != vol->usable_leb_size) {
 785                         ubi_err("bad last_eb_bytes");
 786                         goto fail;
 787                 }
 788                 if (vol->used_bytes != n) {
 789                         ubi_err("bad used_bytes");
 790                         goto fail;
 791                 }
 792         } else {
 793                 if (vol->used_ebs < 0 || vol->used_ebs > vol->reserved_pebs) {
 794                         ubi_err("bad used_ebs");
 795                         goto fail;
 796                 }
 797                 if (vol->last_eb_bytes < 0 ||
 798                     vol->last_eb_bytes > vol->usable_leb_size) {
 799                         ubi_err("bad last_eb_bytes");
 800                         goto fail;
 801                 }
 802                 if (vol->used_bytes < 0 || vol->used_bytes > n ||
 803                     vol->used_bytes < n - vol->usable_leb_size) {
 804                         ubi_err("bad used_bytes");
 805                         goto fail;
 806                 }
 807         }
 808
 809         alignment  = be32_to_cpu(ubi->vtbl[vol_id].alignment);
 810         data_pad   = be32_to_cpu(ubi->vtbl[vol_id].data_pad);
 811         name_len   = be16_to_cpu(ubi->vtbl[vol_id].name_len);
 812         upd_marker = ubi->vtbl[vol_id].upd_marker;
 813         name       = &ubi->vtbl[vol_id].name[0];
 814         if (ubi->vtbl[vol_id].vol_type == UBI_VID_DYNAMIC)
 815                 vol_type = UBI_DYNAMIC_VOLUME;
 816         else
 817                 vol_type = UBI_STATIC_VOLUME;
 818
 819         if (alignment != vol->alignment || data_pad != vol->data_pad ||
 820             upd_marker != vol->upd_marker || vol_type != vol->vol_type ||
 821             name_len!= vol->name_len || strncmp(name, vol->name, name_len)) {
 822                 ubi_err("volume info is different");
 823                 goto fail;
 824         }
 825
 826         spin_unlock(&ubi->volumes_lock);
 827         return;
 828
 829 fail:
 830         ubi_err("paranoid check failed for volume %d", vol_id);
 831         ubi_dbg_dump_vol_info(vol);
 832         ubi_dbg_dump_vtbl_record(&ubi->vtbl[vol_id], vol_id);
 833         spin_unlock(&ubi->volumes_lock);
 834         BUG();
 835 }
 836
 837 /**
 838  * paranoid_check_volumes - check information about all volumes.
 839  * @ubi: UBI device description object
 840  */
 841 static void paranoid_check_volumes(struct ubi_device *ubi)
 842 {
 843         int i;
 844
 845         for (i = 0; i < ubi->vtbl_slots; i++)
 846                 paranoid_check_volume(ubi, i);
 847 }
 848 #endif