drivers/mtd/ubi/vmt.c

   1 /*
   2  * Copyright (c) International Business Machines Corp., 2006
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation;  either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
  12  * the GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  17  *
  18  * Author: Artem Bityutskiy (Битюцкий Артём)
  19  */
  20
  21 /*
  22  * This file contains implementation of volume creation, deletion, updating and
  23  * resizing.
  24  */
  25
  26 #include <linux/err.h>
  27 #include <linux/math64.h>
  28 #include <linux/slab.h>
  29 #include "ubi.h"
  30
  31 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
  32 static int paranoid_check_volumes(struct ubi_device *ubi);
  33 #else
  34 #define paranoid_check_volumes(ubi) 0
  35 #endif
  36
  37 static ssize_t vol_attribute_show(struct device *dev,
  38                                   struct device_attribute *attr, char *buf);
  39
  40 /* Device attributes corresponding to files in '/<sysfs>/class/ubi/ubiX_Y' */
  41 static struct device_attribute attr_vol_reserved_ebs =
  42         __ATTR(reserved_ebs, S_IRUGO, vol_attribute_show, NULL);
  43 static struct device_attribute attr_vol_type =
  44         __ATTR(type, S_IRUGO, vol_attribute_show, NULL);
  45 static struct device_attribute attr_vol_name =
  46         __ATTR(name, S_IRUGO, vol_attribute_show, NULL);
  47 static struct device_attribute attr_vol_corrupted =
  48         __ATTR(corrupted, S_IRUGO, vol_attribute_show, NULL);
  49 static struct device_attribute attr_vol_alignment =
  50         __ATTR(alignment, S_IRUGO, vol_attribute_show, NULL);
  51 static struct device_attribute attr_vol_usable_eb_size =
  52         __ATTR(usable_eb_size, S_IRUGO, vol_attribute_show, NULL);
  53 static struct device_attribute attr_vol_data_bytes =
  54         __ATTR(data_bytes, S_IRUGO, vol_attribute_show, NULL);
  55 static struct device_attribute attr_vol_upd_marker =
  56         __ATTR(upd_marker, S_IRUGO, vol_attribute_show, NULL);
  57
  58 /*
  59  * "Show" method for files in '/<sysfs>/class/ubi/ubiX_Y/'.
  60  *
  61  * Consider a situation:
  62  * A. process 1 opens a sysfs file related to volume Y, say
  63  *    /<sysfs>/class/ubi/ubiX_Y/reserved_ebs;
  64  * B. process 2 removes volume Y;
  65  * C. process 1 starts reading the /<sysfs>/class/ubi/ubiX_Y/reserved_ebs file;
  66  *
  67  * In this situation, this function will return %-ENODEV because it will find
  68  * out that the volume was removed from the @ubi->volumes array.
  69  */
  70 static ssize_t vol_attribute_show(struct device *dev,
  71                                   struct device_attribute *attr, char *buf)
  72 {
  73         int ret;
  74         struct ubi_volume *vol = container_of(dev, struct ubi_volume, dev);
  75         struct ubi_device *ubi;
  76
  77         ubi = ubi_get_device(vol->ubi->ubi_num);
  78         if (!ubi)
  79                 return -ENODEV;
  80
  81         spin_lock(&ubi->volumes_lock);
  82         if (!ubi->volumes[vol->vol_id]) {
  83                 spin_unlock(&ubi->volumes_lock);
  84                 ubi_put_device(ubi);
  85                 return -ENODEV;
  86         }
  87         /* Take a reference to prevent volume removal */
  88         vol->ref_count += 1;
  89         spin_unlock(&ubi->volumes_lock);
  90
  91         if (attr == &attr_vol_reserved_ebs)
  92                 ret = sprintf(buf, "%d\n", vol->reserved_pebs);
  93         else if (attr == &attr_vol_type) {
  94                 const char *tp;
  95
  96                 if (vol->vol_type == UBI_DYNAMIC_VOLUME)
  97                         tp = "dynamic";
  98                 else
  99                         tp = "static";
 100                 ret = sprintf(buf, "%s\n", tp);
 101         } else if (attr == &attr_vol_name)
 102                 ret = sprintf(buf, "%s\n", vol->name);
 103         else if (attr == &attr_vol_corrupted)
 104                 ret = sprintf(buf, "%d\n", vol->corrupted);
 105         else if (attr == &attr_vol_alignment)
 106                 ret = sprintf(buf, "%d\n", vol->alignment);
 107         else if (attr == &attr_vol_usable_eb_size)
 108                 ret = sprintf(buf, "%d\n", vol->usable_leb_size);
 109         else if (attr == &attr_vol_data_bytes)
 110                 ret = sprintf(buf, "%lld\n", vol->used_bytes);
 111         else if (attr == &attr_vol_upd_marker)
 112                 ret = sprintf(buf, "%d\n", vol->upd_marker);
 113         else
 114                 /* This must be a bug */
 115                 ret = -EINVAL;
 116
 117         /* We've done the operation, drop volume and UBI device references */
 118         spin_lock(&ubi->volumes_lock);
 119         vol->ref_count -= 1;
 120         ubi_assert(vol->ref_count >= 0);
 121         spin_unlock(&ubi->volumes_lock);
 122         ubi_put_device(ubi);
 123         return ret;
 124 }
 125
 126 /* Release method for volume devices */
 127 static void vol_release(struct device *dev)
 128 {
 129         struct ubi_volume *vol = container_of(dev, struct ubi_volume, dev);
 130
 131         kfree(vol->eba_tbl);
 132         kfree(vol);
 133 }
 134
 135 /**
 136  * volume_sysfs_init - initialize sysfs for new volume.
 137  * @ubi: UBI device description object
 138  * @vol: volume description object
 139  *
 140  * This function returns zero in case of success and a negative error code in
 141  * case of failure.
 142  *
 143  * Note, this function does not free allocated resources in case of failure -
 144  * the caller does it. This is because this would cause release() here and the
 145  * caller would oops.
 146  */
 147 static int volume_sysfs_init(struct ubi_device *ubi, struct ubi_volume *vol)
 148 {
 149         int err;
 150
 151         err = device_create_file(&vol->dev, &attr_vol_reserved_ebs);
 152         if (err)
 153                 return err;
 154         err = device_create_file(&vol->dev, &attr_vol_type);
 155         if (err)
 156                 return err;
 157         err = device_create_file(&vol->dev, &attr_vol_name);
 158         if (err)
 159                 return err;
 160         err = device_create_file(&vol->dev, &attr_vol_corrupted);
 161         if (err)
 162                 return err;
 163         err = device_create_file(&vol->dev, &attr_vol_alignment);
 164         if (err)
 165                 return err;
 166         err = device_create_file(&vol->dev, &attr_vol_usable_eb_size);
 167         if (err)
 168                 return err;
 169         err = device_create_file(&vol->dev, &attr_vol_data_bytes);
 170         if (err)
 171                 return err;
 172         err = device_create_file(&vol->dev, &attr_vol_upd_marker);
 173         return err;
 174 }
 175
 176 /**
 177  * volume_sysfs_close - close sysfs for a volume.
 178  * @vol: volume description object
 179  */
 180 static void volume_sysfs_close(struct ubi_volume *vol)
 181 {
 182         device_remove_file(&vol->dev, &attr_vol_upd_marker);
 183         device_remove_file(&vol->dev, &attr_vol_data_bytes);
 184         device_remove_file(&vol->dev, &attr_vol_usable_eb_size);
 185         device_remove_file(&vol->dev, &attr_vol_alignment);
 186         device_remove_file(&vol->dev, &attr_vol_corrupted);
 187         device_remove_file(&vol->dev, &attr_vol_name);
 188         device_remove_file(&vol->dev, &attr_vol_type);
 189         device_remove_file(&vol->dev, &attr_vol_reserved_ebs);
 190         device_unregister(&vol->dev);
 191 }
 192
 193 /**
 194  * ubi_create_volume - create volume.
 195  * @ubi: UBI device description object
 196  * @req: volume creation request
 197  *
 198  * This function creates volume described by @req. If @req->vol_id id
 199  * %UBI_VOL_NUM_AUTO, this function automatically assign ID to the new volume
 200  * and saves it in @req->vol_id. Returns zero in case of success and a negative
 201  * error code in case of failure. Note, the caller has to have the
 202  * @ubi->device_mutex locked.
 203  */
 204 int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req)
 205 {
 206         int i, err, vol_id = req->vol_id, do_free = 1;
 207         struct ubi_volume *vol;
 208         struct ubi_vtbl_record vtbl_rec;
 209         dev_t dev;
 210
 211         if (ubi->ro_mode)
 212                 return -EROFS;
 213
 214         vol = kzalloc(sizeof(struct ubi_volume), GFP_KERNEL);
 215         if (!vol)
 216                 return -ENOMEM;
 217
 218         spin_lock(&ubi->volumes_lock);
 219         if (vol_id == UBI_VOL_NUM_AUTO) {
 220                 /* Find unused volume ID */
 221                 dbg_gen("search for vacant volume ID");
 222                 for (i = 0; i < ubi->vtbl_slots; i++)
 223                         if (!ubi->volumes[i]) {
 224                                 vol_id = i;
 225                                 break;
 226                         }
 227
 228                 if (vol_id == UBI_VOL_NUM_AUTO) {
 229                         dbg_err("out of volume IDs");
 230                         err = -ENFILE;
 231                         goto out_unlock;
 232                 }
 233                 req->vol_id = vol_id;
 234         }
 235
 236         dbg_gen("create device %d, volume %d, %llu bytes, type %d, name %s",
 237                 ubi->ubi_num, vol_id, (unsigned long long)req->bytes,
 238                 (int)req->vol_type, req->name);
 239
 240         /* Ensure that this volume does not exist */
 241         err = -EEXIST;
 242         if (ubi->volumes[vol_id]) {
 243                 dbg_err("volume %d already exists", vol_id);
 244                 goto out_unlock;
 245         }
 246
 247         /* Ensure that the name is unique */
 248         for (i = 0; i < ubi->vtbl_slots; i++)
 249                 if (ubi->volumes[i] &&
 250                     ubi->volumes[i]->name_len == req->name_len &&
 251                     !strcmp(ubi->volumes[i]->name, req->name)) {
 252                         dbg_err("volume \"%s\" exists (ID %d)", req->name, i);
 253                         goto out_unlock;
 254                 }
 255
 256         /* Calculate how many eraseblocks are requested */
 257         vol->usable_leb_size = ubi->leb_size - ubi->leb_size % req->alignment;
 258         vol->reserved_pebs += div_u64(req->bytes + vol->usable_leb_size - 1,
 259                                       vol->usable_leb_size);
 260
 261         /* Reserve physical eraseblocks */
 262         if (vol->reserved_pebs > ubi->avail_pebs) {
 263                 dbg_err("not enough PEBs, only %d available", ubi->avail_pebs);
 264                 if (ubi->corr_peb_count)
 265                         dbg_err("%d PEBs are corrupted and not used",
 266                                 ubi->corr_peb_count);
 267                 err = -ENOSPC;
 268                 goto out_unlock;
 269         }
 270         ubi->avail_pebs -= vol->reserved_pebs;
 271         ubi->rsvd_pebs += vol->reserved_pebs;
 272         spin_unlock(&ubi->volumes_lock);
 273
 274         vol->vol_id    = vol_id;
 275         vol->alignment = req->alignment;
 276         vol->data_pad  = ubi->leb_size % vol->alignment;
 277         vol->vol_type  = req->vol_type;
 278         vol->name_len  = req->name_len;
 279         memcpy(vol->name, req->name, vol->name_len);
 280         vol->ubi = ubi;
 281
 282         /*
 283          * Finish all pending erases because there may be some LEBs belonging
 284          * to the same volume ID.
 285          */
 286         err = ubi_wl_flush(ubi);
 287         if (err)
 288                 goto out_acc;
 289
 290         vol->eba_tbl = kmalloc(vol->reserved_pebs * sizeof(int), GFP_KERNEL);
 291         if (!vol->eba_tbl) {
 292                 err = -ENOMEM;
 293                 goto out_acc;
 294         }
 295
 296         for (i = 0; i < vol->reserved_pebs; i++)
 297                 vol->eba_tbl[i] = UBI_LEB_UNMAPPED;
 298
 299         if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
 300                 vol->used_ebs = vol->reserved_pebs;
 301                 vol->last_eb_bytes = vol->usable_leb_size;
 302                 vol->used_bytes =
 303                         (long long)vol->used_ebs * vol->usable_leb_size;
 304         } else {
 305                 vol->used_ebs = div_u64_rem(vol->used_bytes,
 306                                             vol->usable_leb_size,
 307                                             &vol->last_eb_bytes);
 308                 if (vol->last_eb_bytes != 0)
 309                         vol->used_ebs += 1;
 310                 else
 311                         vol->last_eb_bytes = vol->usable_leb_size;
 312         }
 313
 314         /* Register character device for the volume */
 315         cdev_init(&vol->cdev, &ubi_vol_cdev_operations);
 316         vol->cdev.owner = THIS_MODULE;
 317         dev = MKDEV(MAJOR(ubi->cdev.dev), vol_id + 1);
 318         err = cdev_add(&vol->cdev, dev, 1);
 319         if (err) {
 320                 ubi_err("cannot add character device");
 321                 goto out_mapping;
 322         }
 323
 324         vol->dev.release = vol_release;
 325         vol->dev.parent = &ubi->dev;
 326         vol->dev.devt = dev;
 327         vol->dev.class = ubi_class;
 328
 329         dev_set_name(&vol->dev, "%s_%d", ubi->ubi_name, vol->vol_id);
 330         err = device_register(&vol->dev);
 331         if (err) {
 332                 ubi_err("cannot register device");
 333                 goto out_cdev;
 334         }
 335
 336         err = volume_sysfs_init(ubi, vol);
 337         if (err)
 338                 goto out_sysfs;
 339
 340         /* Fill volume table record */
 341         memset(&vtbl_rec, 0, sizeof(struct ubi_vtbl_record));
 342         vtbl_rec.reserved_pebs = cpu_to_be32(vol->reserved_pebs);
 343         vtbl_rec.alignment     = cpu_to_be32(vol->alignment);
 344         vtbl_rec.data_pad      = cpu_to_be32(vol->data_pad);
 345         vtbl_rec.name_len      = cpu_to_be16(vol->name_len);
 346         if (vol->vol_type == UBI_DYNAMIC_VOLUME)
 347                 vtbl_rec.vol_type = UBI_VID_DYNAMIC;
 348         else
 349                 vtbl_rec.vol_type = UBI_VID_STATIC;
 350         memcpy(vtbl_rec.name, vol->name, vol->name_len);
 351
 352         err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
 353         if (err)
 354                 goto out_sysfs;
 355
 356         spin_lock(&ubi->volumes_lock);
 357         ubi->volumes[vol_id] = vol;
 358         ubi->vol_count += 1;
 359         spin_unlock(&ubi->volumes_lock);
 360
 361         ubi_volume_notify(ubi, vol, UBI_VOLUME_ADDED);
 362         if (paranoid_check_volumes(ubi))
 363                 dbg_err("check failed while creating volume %d", vol_id);
 364         return err;
 365
 366 out_sysfs:
 367         /*
 368          * We have registered our device, we should not free the volume
 369          * description object in this function in case of an error - it is
 370          * freed by the release function.
 371          *
 372          * Get device reference to prevent the release function from being
 373          * called just after sysfs has been closed.
 374          */
 375         do_free = 0;
 376         get_device(&vol->dev);
 377         volume_sysfs_close(vol);
 378 out_cdev:
 379         cdev_del(&vol->cdev);
 380 out_mapping:
 381         if (do_free)
 382                 kfree(vol->eba_tbl);
 383 out_acc:
 384         spin_lock(&ubi->volumes_lock);
 385         ubi->rsvd_pebs -= vol->reserved_pebs;
 386         ubi->avail_pebs += vol->reserved_pebs;
 387 out_unlock:
 388         spin_unlock(&ubi->volumes_lock);
 389         if (do_free)
 390                 kfree(vol);
 391         else
 392                 put_device(&vol->dev);
 393         ubi_err("cannot create volume %d, error %d", vol_id, err);
 394         return err;
 395 }
 396
 397 /**
 398  * ubi_remove_volume - remove volume.
 399  * @desc: volume descriptor
 400  * @no_vtbl: do not change volume table if not zero
 401  *
 402  * This function removes volume described by @desc. The volume has to be opened
 403  * in "exclusive" mode. Returns zero in case of success and a negative error
 404  * code in case of failure. The caller has to have the @ubi->device_mutex
 405  * locked.
 406  */
 407 int ubi_remove_volume(struct ubi_volume_desc *desc, int no_vtbl)
 408 {
 409         struct ubi_volume *vol = desc->vol;
 410         struct ubi_device *ubi = vol->ubi;
 411         int i, err, vol_id = vol->vol_id, reserved_pebs = vol->reserved_pebs;
 412
 413         dbg_gen("remove device %d, volume %d", ubi->ubi_num, vol_id);
 414         ubi_assert(desc->mode == UBI_EXCLUSIVE);
 415         ubi_assert(vol == ubi->volumes[vol_id]);
 416
 417         if (ubi->ro_mode)
 418                 return -EROFS;
 419
 420         spin_lock(&ubi->volumes_lock);
 421         if (vol->ref_count > 1) {
 422                 /*
 423                  * The volume is busy, probably someone is reading one of its
 424                  * sysfs files.
 425                  */
 426                 err = -EBUSY;
 427                 goto out_unlock;
 428         }
 429         ubi->volumes[vol_id] = NULL;
 430         spin_unlock(&ubi->volumes_lock);
 431
 432         if (!no_vtbl) {
 433                 err = ubi_change_vtbl_record(ubi, vol_id, NULL);
 434                 if (err)
 435                         goto out_err;
 436         }
 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         cdev_del(&vol->cdev);
 445         volume_sysfs_close(vol);
 446
 447         spin_lock(&ubi->volumes_lock);
 448         ubi->rsvd_pebs -= reserved_pebs;
 449         ubi->avail_pebs += reserved_pebs;
 450         i = ubi->beb_rsvd_level - ubi->beb_rsvd_pebs;
 451         if (i > 0) {
 452                 i = ubi->avail_pebs >= i ? i : ubi->avail_pebs;
 453                 ubi->avail_pebs -= i;
 454                 ubi->rsvd_pebs += i;
 455                 ubi->beb_rsvd_pebs += i;
 456                 if (i > 0)
 457                         ubi_msg("reserve more %d PEBs", i);
 458         }
 459         ubi->vol_count -= 1;
 460         spin_unlock(&ubi->volumes_lock);
 461
 462         ubi_volume_notify(ubi, vol, UBI_VOLUME_REMOVED);
 463         if (!no_vtbl && paranoid_check_volumes(ubi))
 464                 dbg_err("check failed while removing volume %d", vol_id);
 465
 466         return err;
 467
 468 out_err:
 469         ubi_err("cannot remove volume %d, error %d", vol_id, err);
 470         spin_lock(&ubi->volumes_lock);
 471         ubi->volumes[vol_id] = vol;
 472 out_unlock:
 473         spin_unlock(&ubi->volumes_lock);
 474         return err;
 475 }
 476
 477 /**
 478  * ubi_resize_volume - re-size volume.
 479  * @desc: volume descriptor
 480  * @reserved_pebs: new size in physical eraseblocks
 481  *
 482  * This function re-sizes the volume and returns zero in case of success, and a
 483  * negative error code in case of failure. The caller has to have the
 484  * @ubi->device_mutex locked.
 485  */
 486 int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs)
 487 {
 488         int i, err, pebs, *new_mapping;
 489         struct ubi_volume *vol = desc->vol;
 490         struct ubi_device *ubi = vol->ubi;
 491         struct ubi_vtbl_record vtbl_rec;
 492         int vol_id = vol->vol_id;
 493
 494         if (ubi->ro_mode)
 495                 return -EROFS;
 496
 497         dbg_gen("re-size device %d, volume %d to from %d to %d PEBs",
 498                 ubi->ubi_num, vol_id, vol->reserved_pebs, reserved_pebs);
 499
 500         if (vol->vol_type == UBI_STATIC_VOLUME &&
 501             reserved_pebs < vol->used_ebs) {
 502                 dbg_err("too small size %d, %d LEBs contain data",
 503                         reserved_pebs, vol->used_ebs);
 504                 return -EINVAL;
 505         }
 506
 507         /* If the size is the same, we have nothing to do */
 508         if (reserved_pebs == vol->reserved_pebs)
 509                 return 0;
 510
 511         new_mapping = kmalloc(reserved_pebs * sizeof(int), GFP_KERNEL);
 512         if (!new_mapping)
 513                 return -ENOMEM;
 514
 515         for (i = 0; i < reserved_pebs; i++)
 516                 new_mapping[i] = UBI_LEB_UNMAPPED;
 517
 518         spin_lock(&ubi->volumes_lock);
 519         if (vol->ref_count > 1) {
 520                 spin_unlock(&ubi->volumes_lock);
 521                 err = -EBUSY;
 522                 goto out_free;
 523         }
 524         spin_unlock(&ubi->volumes_lock);
 525
 526         /* Reserve physical eraseblocks */
 527         pebs = reserved_pebs - vol->reserved_pebs;
 528         if (pebs > 0) {
 529                 spin_lock(&ubi->volumes_lock);
 530                 if (pebs > ubi->avail_pebs) {
 531                         dbg_err("not enough PEBs: requested %d, available %d",
 532                                 pebs, ubi->avail_pebs);
 533                         if (ubi->corr_peb_count)
 534                                 dbg_err("%d PEBs are corrupted and not used",
 535                                         ubi->corr_peb_count);
 536                         spin_unlock(&ubi->volumes_lock);
 537                         err = -ENOSPC;
 538                         goto out_free;
 539                 }
 540                 ubi->avail_pebs -= pebs;
 541                 ubi->rsvd_pebs += pebs;
 542                 for (i = 0; i < vol->reserved_pebs; i++)
 543                         new_mapping[i] = vol->eba_tbl[i];
 544                 kfree(vol->eba_tbl);
 545                 vol->eba_tbl = new_mapping;
 546                 spin_unlock(&ubi->volumes_lock);
 547         }
 548
 549         /* Change volume table record */
 550         memcpy(&vtbl_rec, &ubi->vtbl[vol_id], sizeof(struct ubi_vtbl_record));
 551         vtbl_rec.reserved_pebs = cpu_to_be32(reserved_pebs);
 552         err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
 553         if (err)
 554                 goto out_acc;
 555
 556         if (pebs < 0) {
 557                 for (i = 0; i < -pebs; i++) {
 558                         err = ubi_eba_unmap_leb(ubi, vol, reserved_pebs + i);
 559                         if (err)
 560                                 goto out_acc;
 561                 }
 562                 spin_lock(&ubi->volumes_lock);
 563                 ubi->rsvd_pebs += pebs;
 564                 ubi->avail_pebs -= pebs;
 565                 pebs = ubi->beb_rsvd_level - ubi->beb_rsvd_pebs;
 566                 if (pebs > 0) {
 567                         pebs = ubi->avail_pebs >= pebs ? pebs : ubi->avail_pebs;
 568                         ubi->avail_pebs -= pebs;
 569                         ubi->rsvd_pebs += pebs;
 570                         ubi->beb_rsvd_pebs += pebs;
 571                         if (pebs > 0)
 572                                 ubi_msg("reserve more %d PEBs", pebs);
 573                 }
 574                 for (i = 0; i < reserved_pebs; i++)
 575                         new_mapping[i] = vol->eba_tbl[i];
 576                 kfree(vol->eba_tbl);
 577                 vol->eba_tbl = new_mapping;
 578                 spin_unlock(&ubi->volumes_lock);
 579         }
 580
 581         vol->reserved_pebs = reserved_pebs;
 582         if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
 583                 vol->used_ebs = reserved_pebs;
 584                 vol->last_eb_bytes = vol->usable_leb_size;
 585                 vol->used_bytes =
 586                         (long long)vol->used_ebs * vol->usable_leb_size;
 587         }
 588
 589         ubi_volume_notify(ubi, vol, UBI_VOLUME_RESIZED);
 590         if (paranoid_check_volumes(ubi))
 591                 dbg_err("check failed while re-sizing volume %d", vol_id);
 592         return err;
 593
 594 out_acc:
 595         if (pebs > 0) {
 596                 spin_lock(&ubi->volumes_lock);
 597                 ubi->rsvd_pebs -= pebs;
 598                 ubi->avail_pebs += pebs;
 599                 spin_unlock(&ubi->volumes_lock);
 600         }
 601 out_free:
 602         kfree(new_mapping);
 603         return err;
 604 }
 605
 606 /**
 607  * ubi_rename_volumes - re-name UBI volumes.
 608  * @ubi: UBI device description object
 609  * @rename_list: list of &struct ubi_rename_entry objects
 610  *
 611  * This function re-names or removes volumes specified in the re-name list.
 612  * Returns zero in case of success and a negative error code in case of
 613  * failure.
 614  */
 615 int ubi_rename_volumes(struct ubi_device *ubi, struct list_head *rename_list)
 616 {
 617         int err;
 618         struct ubi_rename_entry *re;
 619
 620         err = ubi_vtbl_rename_volumes(ubi, rename_list);
 621         if (err)
 622                 return err;
 623
 624         list_for_each_entry(re, rename_list, list) {
 625                 if (re->remove) {
 626                         err = ubi_remove_volume(re->desc, 1);
 627                         if (err)
 628                                 break;
 629                 } else {
 630                         struct ubi_volume *vol = re->desc->vol;
 631
 632                         spin_lock(&ubi->volumes_lock);
 633                         vol->name_len = re->new_name_len;
 634                         memcpy(vol->name, re->new_name, re->new_name_len + 1);
 635                         spin_unlock(&ubi->volumes_lock);
 636                         ubi_volume_notify(ubi, vol, UBI_VOLUME_RENAMED);
 637                 }
 638         }
 639
 640         if (!err && paranoid_check_volumes(ubi))
 641                 ;
 642         return err;
 643 }
 644
 645 /**
 646  * ubi_add_volume - add volume.
 647  * @ubi: UBI device description object
 648  * @vol: volume description object
 649  *
 650  * This function adds an existing volume and initializes all its data
 651  * structures. Returns zero in case of success and a negative error code in
 652  * case of failure.
 653  */
 654 int ubi_add_volume(struct ubi_device *ubi, struct ubi_volume *vol)
 655 {
 656         int err, vol_id = vol->vol_id;
 657         dev_t dev;
 658
 659         dbg_gen("add volume %d", vol_id);
 660
 661         /* Register character device for the volume */
 662         cdev_init(&vol->cdev, &ubi_vol_cdev_operations);
 663         vol->cdev.owner = THIS_MODULE;
 664         dev = MKDEV(MAJOR(ubi->cdev.dev), vol->vol_id + 1);
 665         err = cdev_add(&vol->cdev, dev, 1);
 666         if (err) {
 667                 ubi_err("cannot add character device for volume %d, error %d",
 668                         vol_id, err);
 669                 return err;
 670         }
 671
 672         vol->dev.release = vol_release;
 673         vol->dev.parent = &ubi->dev;
 674         vol->dev.devt = dev;
 675         vol->dev.class = ubi_class;
 676         dev_set_name(&vol->dev, "%s_%d", ubi->ubi_name, vol->vol_id);
 677         err = device_register(&vol->dev);
 678         if (err)
 679                 goto out_cdev;
 680
 681         err = volume_sysfs_init(ubi, vol);
 682         if (err) {
 683                 cdev_del(&vol->cdev);
 684                 volume_sysfs_close(vol);
 685                 return err;
 686         }
 687
 688         if (paranoid_check_volumes(ubi))
 689                 dbg_err("check failed while adding volume %d", vol_id);
 690         return err;
 691
 692 out_cdev:
 693         cdev_del(&vol->cdev);
 694         return err;
 695 }
 696
 697 /**
 698  * ubi_free_volume - free volume.
 699  * @ubi: UBI device description object
 700  * @vol: volume description object
 701  *
 702  * This function frees all resources for volume @vol but does not remove it.
 703  * Used only when the UBI device is detached.
 704  */
 705 void ubi_free_volume(struct ubi_device *ubi, struct ubi_volume *vol)
 706 {
 707         dbg_gen("free volume %d", vol->vol_id);
 708
 709         ubi->volumes[vol->vol_id] = NULL;
 710         cdev_del(&vol->cdev);
 711         volume_sysfs_close(vol);
 712 }
 713
 714 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
 715
 716 /**
 717  * paranoid_check_volume - check volume information.
 718  * @ubi: UBI device description object
 719  * @vol_id: volume ID
 720  *
 721  * Returns zero if volume is all right and a a negative error code if not.
 722  */
 723 static int paranoid_check_volume(struct ubi_device *ubi, int vol_id)
 724 {
 725         int idx = vol_id2idx(ubi, vol_id);
 726         int reserved_pebs, alignment, data_pad, vol_type, name_len, upd_marker;
 727         const struct ubi_volume *vol;
 728         long long n;
 729         const char *name;
 730
 731         spin_lock(&ubi->volumes_lock);
 732         reserved_pebs = be32_to_cpu(ubi->vtbl[vol_id].reserved_pebs);
 733         vol = ubi->volumes[idx];
 734
 735         if (!vol) {
 736                 if (reserved_pebs) {
 737                         ubi_err("no volume info, but volume exists");
 738                         goto fail;
 739                 }
 740                 spin_unlock(&ubi->volumes_lock);
 741                 return 0;
 742         }
 743
 744         if (vol->reserved_pebs < 0 || vol->alignment < 0 || vol->data_pad < 0 ||
 745             vol->name_len < 0) {
 746                 ubi_err("negative values");
 747                 goto fail;
 748         }
 749         if (vol->alignment > ubi->leb_size || vol->alignment == 0) {
 750                 ubi_err("bad alignment");
 751                 goto fail;
 752         }
 753
 754         n = vol->alignment & (ubi->min_io_size - 1);
 755         if (vol->alignment != 1 && n) {
 756                 ubi_err("alignment is not multiple of min I/O unit");
 757                 goto fail;
 758         }
 759
 760         n = ubi->leb_size % vol->alignment;
 761         if (vol->data_pad != n) {
 762                 ubi_err("bad data_pad, has to be %lld", n);
 763                 goto fail;
 764         }
 765
 766         if (vol->vol_type != UBI_DYNAMIC_VOLUME &&
 767             vol->vol_type != UBI_STATIC_VOLUME) {
 768                 ubi_err("bad vol_type");
 769                 goto fail;
 770         }
 771
 772         if (vol->upd_marker && vol->corrupted) {
 773                 dbg_err("update marker and corrupted simultaneously");
 774                 goto fail;
 775         }
 776
 777         if (vol->reserved_pebs > ubi->good_peb_count) {
 778                 ubi_err("too large reserved_pebs");
 779                 goto fail;
 780         }
 781
 782         n = ubi->leb_size - vol->data_pad;
 783         if (vol->usable_leb_size != ubi->leb_size - vol->data_pad) {
 784                 ubi_err("bad usable_leb_size, has to be %lld", n);
 785                 goto fail;
 786         }
 787
 788         if (vol->name_len > UBI_VOL_NAME_MAX) {
 789                 ubi_err("too long volume name, max is %d", UBI_VOL_NAME_MAX);
 790                 goto fail;
 791         }
 792
 793         if (!vol->name) {
 794                 ubi_err("NULL volume name");
 795                 goto fail;
 796         }
 797
 798         n = strnlen(vol->name, vol->name_len + 1);
 799         if (n != vol->name_len) {
 800                 ubi_err("bad name_len %lld", n);
 801                 goto fail;
 802         }
 803
 804         n = (long long)vol->used_ebs * vol->usable_leb_size;
 805         if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
 806                 if (vol->corrupted) {
 807                         ubi_err("corrupted dynamic volume");
 808                         goto fail;
 809                 }
 810                 if (vol->used_ebs != vol->reserved_pebs) {
 811                         ubi_err("bad used_ebs");
 812                         goto fail;
 813                 }
 814                 if (vol->last_eb_bytes != vol->usable_leb_size) {
 815                         ubi_err("bad last_eb_bytes");
 816                         goto fail;
 817                 }
 818                 if (vol->used_bytes != n) {
 819                         ubi_err("bad used_bytes");
 820                         goto fail;
 821                 }
 822         } else {
 823                 if (vol->used_ebs < 0 || vol->used_ebs > vol->reserved_pebs) {
 824                         ubi_err("bad used_ebs");
 825                         goto fail;
 826                 }
 827                 if (vol->last_eb_bytes < 0 ||
 828                     vol->last_eb_bytes > vol->usable_leb_size) {
 829                         ubi_err("bad last_eb_bytes");
 830                         goto fail;
 831                 }
 832                 if (vol->used_bytes < 0 || vol->used_bytes > n ||
 833                     vol->used_bytes < n - vol->usable_leb_size) {
 834                         ubi_err("bad used_bytes");
 835                         goto fail;
 836                 }
 837         }
 838
 839         alignment  = be32_to_cpu(ubi->vtbl[vol_id].alignment);
 840         data_pad   = be32_to_cpu(ubi->vtbl[vol_id].data_pad);
 841         name_len   = be16_to_cpu(ubi->vtbl[vol_id].name_len);
 842         upd_marker = ubi->vtbl[vol_id].upd_marker;
 843         name       = &ubi->vtbl[vol_id].name[0];
 844         if (ubi->vtbl[vol_id].vol_type == UBI_VID_DYNAMIC)
 845                 vol_type = UBI_DYNAMIC_VOLUME;
 846         else
 847                 vol_type = UBI_STATIC_VOLUME;
 848
 849         if (alignment != vol->alignment || data_pad != vol->data_pad ||
 850             upd_marker != vol->upd_marker || vol_type != vol->vol_type ||
 851             name_len != vol->name_len || strncmp(name, vol->name, name_len)) {
 852                 ubi_err("volume info is different");
 853                 goto fail;
 854         }
 855
 856         spin_unlock(&ubi->volumes_lock);
 857         return 0;
 858
 859 fail:
 860         ubi_err("paranoid check failed for volume %d", vol_id);
 861         if (vol)
 862                 ubi_dbg_dump_vol_info(vol);
 863         ubi_dbg_dump_vtbl_record(&ubi->vtbl[vol_id], vol_id);
 864         dump_stack();
 865         spin_unlock(&ubi->volumes_lock);
 866         return -EINVAL;
 867 }
 868
 869 /**
 870  * paranoid_check_volumes - check information about all volumes.
 871  * @ubi: UBI device description object
 872  *
 873  * Returns zero if volumes are all right and a a negative error code if not.
 874  */
 875 static int paranoid_check_volumes(struct ubi_device *ubi)
 876 {
 877         int i, err = 0;
 878
 879         for (i = 0; i < ubi->vtbl_slots; i++) {
 880                 err = paranoid_check_volume(ubi, i);
 881                 if (err)
 882                         break;
 883         }
 884
 885         return err;
 886 }
 887 #endif