drivers/mtd/ubi/cdev.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 includes implementation of UBI character device operations.
  23  *
  24  * There are two kinds of character devices in UBI: UBI character devices and
  25  * UBI volume character devices. UBI character devices allow users to
  26  * manipulate whole volumes: create, remove, and re-size them. Volume character
  27  * devices provide volume I/O capabilities.
  28  *
  29  * Major and minor numbers are assigned dynamically to both UBI and volume
  30  * character devices.
  31  *
  32  * Well, there is the third kind of character devices - the UBI control
  33  * character device, which allows to manipulate by UBI devices - create and
  34  * delete them. In other words, it is used for attaching and detaching MTD
  35  * devices.
  36  */
  37
  38 #include <linux/module.h>
  39 #include <linux/stat.h>
  40 #include <linux/ioctl.h>
  41 #include <linux/capability.h>
  42 #include <linux/uaccess.h>
  43 #include <linux/compat.h>
  44 #include <linux/math64.h>
  45 #include <mtd/ubi-user.h>
  46 #include "ubi.h"
  47
  48 /**
  49  * get_exclusive - get exclusive access to an UBI volume.
  50  * @desc: volume descriptor
  51  *
  52  * This function changes UBI volume open mode to "exclusive". Returns previous
  53  * mode value (positive integer) in case of success and a negative error code
  54  * in case of failure.
  55  */
  56 static int get_exclusive(struct ubi_volume_desc *desc)
  57 {
  58         int users, err;
  59         struct ubi_volume *vol = desc->vol;
  60
  61         spin_lock(&vol->ubi->volumes_lock);
  62         users = vol->readers + vol->writers + vol->exclusive;
  63         ubi_assert(users > 0);
  64         if (users > 1) {
  65                 dbg_err("%d users for volume %d", users, vol->vol_id);
  66                 err = -EBUSY;
  67         } else {
  68                 vol->readers = vol->writers = 0;
  69                 vol->exclusive = 1;
  70                 err = desc->mode;
  71                 desc->mode = UBI_EXCLUSIVE;
  72         }
  73         spin_unlock(&vol->ubi->volumes_lock);
  74
  75         return err;
  76 }
  77
  78 /**
  79  * revoke_exclusive - revoke exclusive mode.
  80  * @desc: volume descriptor
  81  * @mode: new mode to switch to
  82  */
  83 static void revoke_exclusive(struct ubi_volume_desc *desc, int mode)
  84 {
  85         struct ubi_volume *vol = desc->vol;
  86
  87         spin_lock(&vol->ubi->volumes_lock);
  88         ubi_assert(vol->readers == 0 && vol->writers == 0);
  89         ubi_assert(vol->exclusive == 1 && desc->mode == UBI_EXCLUSIVE);
  90         vol->exclusive = 0;
  91         if (mode == UBI_READONLY)
  92                 vol->readers = 1;
  93         else if (mode == UBI_READWRITE)
  94                 vol->writers = 1;
  95         else
  96                 vol->exclusive = 1;
  97         spin_unlock(&vol->ubi->volumes_lock);
  98
  99         desc->mode = mode;
 100 }
 101
 102 static int vol_cdev_open(struct inode *inode, struct file *file)
 103 {
 104         struct ubi_volume_desc *desc;
 105         int vol_id = iminor(inode) - 1, mode, ubi_num;
 106
 107         ubi_num = ubi_major2num(imajor(inode));
 108         if (ubi_num < 0)
 109                 return ubi_num;
 110
 111         if (file->f_mode & FMODE_WRITE)
 112                 mode = UBI_READWRITE;
 113         else
 114                 mode = UBI_READONLY;
 115
 116         dbg_gen("open volume %d, mode %d", vol_id, mode);
 117
 118         desc = ubi_open_volume(ubi_num, vol_id, mode);
 119         if (IS_ERR(desc))
 120                 return PTR_ERR(desc);
 121
 122         file->private_data = desc;
 123         return 0;
 124 }
 125
 126 static int vol_cdev_release(struct inode *inode, struct file *file)
 127 {
 128         struct ubi_volume_desc *desc = file->private_data;
 129         struct ubi_volume *vol = desc->vol;
 130
 131         dbg_gen("release volume %d, mode %d", vol->vol_id, desc->mode);
 132
 133         if (vol->updating) {
 134                 ubi_warn("update of volume %d not finished, volume is damaged",
 135                          vol->vol_id);
 136                 ubi_assert(!vol->changing_leb);
 137                 vol->updating = 0;
 138                 vfree(vol->upd_buf);
 139         } else if (vol->changing_leb) {
 140                 dbg_gen("only %lld of %lld bytes received for atomic LEB change"
 141                         " for volume %d:%d, cancel", vol->upd_received,
 142                         vol->upd_bytes, vol->ubi->ubi_num, vol->vol_id);
 143                 vol->changing_leb = 0;
 144                 vfree(vol->upd_buf);
 145         }
 146
 147         ubi_close_volume(desc);
 148         return 0;
 149 }
 150
 151 static loff_t vol_cdev_llseek(struct file *file, loff_t offset, int origin)
 152 {
 153         struct ubi_volume_desc *desc = file->private_data;
 154         struct ubi_volume *vol = desc->vol;
 155         loff_t new_offset;
 156
 157         if (vol->updating) {
 158                  /* Update is in progress, seeking is prohibited */
 159                 dbg_err("updating");
 160                 return -EBUSY;
 161         }
 162
 163         switch (origin) {
 164         case 0: /* SEEK_SET */
 165                 new_offset = offset;
 166                 break;
 167         case 1: /* SEEK_CUR */
 168                 new_offset = file->f_pos + offset;
 169                 break;
 170         case 2: /* SEEK_END */
 171                 new_offset = vol->used_bytes + offset;
 172                 break;
 173         default:
 174                 return -EINVAL;
 175         }
 176
 177         if (new_offset < 0 || new_offset > vol->used_bytes) {
 178                 dbg_err("bad seek %lld", new_offset);
 179                 return -EINVAL;
 180         }
 181
 182         dbg_gen("seek volume %d, offset %lld, origin %d, new offset %lld",
 183                 vol->vol_id, offset, origin, new_offset);
 184
 185         file->f_pos = new_offset;
 186         return new_offset;
 187 }
 188
 189 static ssize_t vol_cdev_read(struct file *file, __user char *buf, size_t count,
 190                              loff_t *offp)
 191 {
 192         struct ubi_volume_desc *desc = file->private_data;
 193         struct ubi_volume *vol = desc->vol;
 194         struct ubi_device *ubi = vol->ubi;
 195         int err, lnum, off, len,  tbuf_size;
 196         size_t count_save = count;
 197         void *tbuf;
 198
 199         dbg_gen("read %zd bytes from offset %lld of volume %d",
 200                 count, *offp, vol->vol_id);
 201
 202         if (vol->updating) {
 203                 dbg_err("updating");
 204                 return -EBUSY;
 205         }
 206         if (vol->upd_marker) {
 207                 dbg_err("damaged volume, update marker is set");
 208                 return -EBADF;
 209         }
 210         if (*offp == vol->used_bytes || count == 0)
 211                 return 0;
 212
 213         if (vol->corrupted)
 214                 dbg_gen("read from corrupted volume %d", vol->vol_id);
 215
 216         if (*offp + count > vol->used_bytes)
 217                 count_save = count = vol->used_bytes - *offp;
 218
 219         tbuf_size = vol->usable_leb_size;
 220         if (count < tbuf_size)
 221                 tbuf_size = ALIGN(count, ubi->min_io_size);
 222         tbuf = vmalloc(tbuf_size);
 223         if (!tbuf)
 224                 return -ENOMEM;
 225
 226         len = count > tbuf_size ? tbuf_size : count;
 227         lnum = div_u64_rem(*offp, vol->usable_leb_size, &off);
 228
 229         do {
 230                 cond_resched();
 231
 232                 if (off + len >= vol->usable_leb_size)
 233                         len = vol->usable_leb_size - off;
 234
 235                 err = ubi_eba_read_leb(ubi, vol, lnum, tbuf, off, len, 0);
 236                 if (err)
 237                         break;
 238
 239                 off += len;
 240                 if (off == vol->usable_leb_size) {
 241                         lnum += 1;
 242                         off -= vol->usable_leb_size;
 243                 }
 244
 245                 count -= len;
 246                 *offp += len;
 247
 248                 err = copy_to_user(buf, tbuf, len);
 249                 if (err) {
 250                         err = -EFAULT;
 251                         break;
 252                 }
 253
 254                 buf += len;
 255                 len = count > tbuf_size ? tbuf_size : count;
 256         } while (count);
 257
 258         vfree(tbuf);
 259         return err ? err : count_save - count;
 260 }
 261
 262 #ifdef CONFIG_MTD_UBI_DEBUG_USERSPACE_IO
 263
 264 /*
 265  * This function allows to directly write to dynamic UBI volumes, without
 266  * issuing the volume update operation. Available only as a debugging feature.
 267  * Very useful for testing UBI.
 268  */
 269 static ssize_t vol_cdev_direct_write(struct file *file, const char __user *buf,
 270                                      size_t count, loff_t *offp)
 271 {
 272         struct ubi_volume_desc *desc = file->private_data;
 273         struct ubi_volume *vol = desc->vol;
 274         struct ubi_device *ubi = vol->ubi;
 275         int lnum, off, len, tbuf_size, err = 0;
 276         size_t count_save = count;
 277         char *tbuf;
 278
 279         dbg_gen("requested: write %zd bytes to offset %lld of volume %u",
 280                 count, *offp, vol->vol_id);
 281
 282         if (vol->vol_type == UBI_STATIC_VOLUME)
 283                 return -EROFS;
 284
 285         lnum = div_u64_rem(*offp, vol->usable_leb_size, &off);
 286         if (off & (ubi->min_io_size - 1)) {
 287                 dbg_err("unaligned position");
 288                 return -EINVAL;
 289         }
 290
 291         if (*offp + count > vol->used_bytes)
 292                 count_save = count = vol->used_bytes - *offp;
 293
 294         /* We can write only in fractions of the minimum I/O unit */
 295         if (count & (ubi->min_io_size - 1)) {
 296                 dbg_err("unaligned write length");
 297                 return -EINVAL;
 298         }
 299
 300         tbuf_size = vol->usable_leb_size;
 301         if (count < tbuf_size)
 302                 tbuf_size = ALIGN(count, ubi->min_io_size);
 303         tbuf = vmalloc(tbuf_size);
 304         if (!tbuf)
 305                 return -ENOMEM;
 306
 307         len = count > tbuf_size ? tbuf_size : count;
 308
 309         while (count) {
 310                 cond_resched();
 311
 312                 if (off + len >= vol->usable_leb_size)
 313                         len = vol->usable_leb_size - off;
 314
 315                 err = copy_from_user(tbuf, buf, len);
 316                 if (err) {
 317                         err = -EFAULT;
 318                         break;
 319                 }
 320
 321                 err = ubi_eba_write_leb(ubi, vol, lnum, tbuf, off, len,
 322                                         UBI_UNKNOWN);
 323                 if (err)
 324                         break;
 325
 326                 off += len;
 327                 if (off == vol->usable_leb_size) {
 328                         lnum += 1;
 329                         off -= vol->usable_leb_size;
 330                 }
 331
 332                 count -= len;
 333                 *offp += len;
 334                 buf += len;
 335                 len = count > tbuf_size ? tbuf_size : count;
 336         }
 337
 338         vfree(tbuf);
 339         return err ? err : count_save - count;
 340 }
 341
 342 #else
 343 #define vol_cdev_direct_write(file, buf, count, offp) (-EPERM)
 344 #endif /* CONFIG_MTD_UBI_DEBUG_USERSPACE_IO */
 345
 346 static ssize_t vol_cdev_write(struct file *file, const char __user *buf,
 347                               size_t count, loff_t *offp)
 348 {
 349         int err = 0;
 350         struct ubi_volume_desc *desc = file->private_data;
 351         struct ubi_volume *vol = desc->vol;
 352         struct ubi_device *ubi = vol->ubi;
 353
 354         if (!vol->updating && !vol->changing_leb)
 355                 return vol_cdev_direct_write(file, buf, count, offp);
 356
 357         if (vol->updating)
 358                 err = ubi_more_update_data(ubi, vol, buf, count);
 359         else
 360                 err = ubi_more_leb_change_data(ubi, vol, buf, count);
 361
 362         if (err < 0) {
 363                 ubi_err("cannot accept more %zd bytes of data, error %d",
 364                         count, err);
 365                 return err;
 366         }
 367
 368         if (err) {
 369                 /*
 370                  * The operation is finished, @err contains number of actually
 371                  * written bytes.
 372                  */
 373                 count = err;
 374
 375                 if (vol->changing_leb) {
 376                         revoke_exclusive(desc, UBI_READWRITE);
 377                         return count;
 378                 }
 379
 380                 err = ubi_check_volume(ubi, vol->vol_id);
 381                 if (err < 0)
 382                         return err;
 383
 384                 if (err) {
 385                         ubi_warn("volume %d on UBI device %d is corrupted",
 386                                  vol->vol_id, ubi->ubi_num);
 387                         vol->corrupted = 1;
 388                 }
 389                 vol->checked = 1;
 390                 ubi_gluebi_updated(vol);
 391                 revoke_exclusive(desc, UBI_READWRITE);
 392         }
 393
 394         return count;
 395 }
 396
 397 static long vol_cdev_ioctl(struct file *file, unsigned int cmd,
 398                            unsigned long arg)
 399 {
 400         int err = 0;
 401         struct ubi_volume_desc *desc = file->private_data;
 402         struct ubi_volume *vol = desc->vol;
 403         struct ubi_device *ubi = vol->ubi;
 404         void __user *argp = (void __user *)arg;
 405
 406         switch (cmd) {
 407         /* Volume update command */
 408         case UBI_IOCVOLUP:
 409         {
 410                 int64_t bytes, rsvd_bytes;
 411
 412                 if (!capable(CAP_SYS_RESOURCE)) {
 413                         err = -EPERM;
 414                         break;
 415                 }
 416
 417                 err = copy_from_user(&bytes, argp, sizeof(int64_t));
 418                 if (err) {
 419                         err = -EFAULT;
 420                         break;
 421                 }
 422
 423                 if (desc->mode == UBI_READONLY) {
 424                         err = -EROFS;
 425                         break;
 426                 }
 427
 428                 rsvd_bytes = (long long)vol->reserved_pebs *
 429                                         ubi->leb_size-vol->data_pad;
 430                 if (bytes < 0 || bytes > rsvd_bytes) {
 431                         err = -EINVAL;
 432                         break;
 433                 }
 434
 435                 err = get_exclusive(desc);
 436                 if (err < 0)
 437                         break;
 438
 439                 err = ubi_start_update(ubi, vol, bytes);
 440                 if (bytes == 0)
 441                         revoke_exclusive(desc, UBI_READWRITE);
 442                 break;
 443         }
 444
 445         /* Atomic logical eraseblock change command */
 446         case UBI_IOCEBCH:
 447         {
 448                 struct ubi_leb_change_req req;
 449
 450                 err = copy_from_user(&req, argp,
 451                                      sizeof(struct ubi_leb_change_req));
 452                 if (err) {
 453                         err = -EFAULT;
 454                         break;
 455                 }
 456
 457                 if (desc->mode == UBI_READONLY ||
 458                     vol->vol_type == UBI_STATIC_VOLUME) {
 459                         err = -EROFS;
 460                         break;
 461                 }
 462
 463                 /* Validate the request */
 464                 err = -EINVAL;
 465                 if (req.lnum < 0 || req.lnum >= vol->reserved_pebs ||
 466                     req.bytes < 0 || req.lnum >= vol->usable_leb_size)
 467                         break;
 468                 if (req.dtype != UBI_LONGTERM && req.dtype != UBI_SHORTTERM &&
 469                     req.dtype != UBI_UNKNOWN)
 470                         break;
 471
 472                 err = get_exclusive(desc);
 473                 if (err < 0)
 474                         break;
 475
 476                 err = ubi_start_leb_change(ubi, vol, &req);
 477                 if (req.bytes == 0)
 478                         revoke_exclusive(desc, UBI_READWRITE);
 479                 break;
 480         }
 481
 482         /* Logical eraseblock erasure command */
 483         case UBI_IOCEBER:
 484         {
 485                 int32_t lnum;
 486
 487                 err = get_user(lnum, (__user int32_t *)argp);
 488                 if (err) {
 489                         err = -EFAULT;
 490                         break;
 491                 }
 492
 493                 if (desc->mode == UBI_READONLY ||
 494                     vol->vol_type == UBI_STATIC_VOLUME) {
 495                         err = -EROFS;
 496                         break;
 497                 }
 498
 499                 if (lnum < 0 || lnum >= vol->reserved_pebs) {
 500                         err = -EINVAL;
 501                         break;
 502                 }
 503
 504                 dbg_gen("erase LEB %d:%d", vol->vol_id, lnum);
 505                 err = ubi_eba_unmap_leb(ubi, vol, lnum);
 506                 if (err)
 507                         break;
 508
 509                 err = ubi_wl_flush(ubi);
 510                 break;
 511         }
 512
 513         /* Logical eraseblock map command */
 514         case UBI_IOCEBMAP:
 515         {
 516                 struct ubi_map_req req;
 517
 518                 err = copy_from_user(&req, argp, sizeof(struct ubi_map_req));
 519                 if (err) {
 520                         err = -EFAULT;
 521                         break;
 522                 }
 523                 err = ubi_leb_map(desc, req.lnum, req.dtype);
 524                 break;
 525         }
 526
 527         /* Logical eraseblock un-map command */
 528         case UBI_IOCEBUNMAP:
 529         {
 530                 int32_t lnum;
 531
 532                 err = get_user(lnum, (__user int32_t *)argp);
 533                 if (err) {
 534                         err = -EFAULT;
 535                         break;
 536                 }
 537                 err = ubi_leb_unmap(desc, lnum);
 538                 break;
 539         }
 540
 541         /* Check if logical eraseblock is mapped command */
 542         case UBI_IOCEBISMAP:
 543         {
 544                 int32_t lnum;
 545
 546                 err = get_user(lnum, (__user int32_t *)argp);
 547                 if (err) {
 548                         err = -EFAULT;
 549                         break;
 550                 }
 551                 err = ubi_is_mapped(desc, lnum);
 552                 break;
 553         }
 554
 555         default:
 556                 err = -ENOTTY;
 557                 break;
 558         }
 559         return err;
 560 }
 561
 562 /**
 563  * verify_mkvol_req - verify volume creation request.
 564  * @ubi: UBI device description object
 565  * @req: the request to check
 566  *
 567  * This function zero if the request is correct, and %-EINVAL if not.
 568  */
 569 static int verify_mkvol_req(const struct ubi_device *ubi,
 570                             const struct ubi_mkvol_req *req)
 571 {
 572         int n, err = -EINVAL;
 573
 574         if (req->bytes < 0 || req->alignment < 0 || req->vol_type < 0 ||
 575             req->name_len < 0)
 576                 goto bad;
 577
 578         if ((req->vol_id < 0 || req->vol_id >= ubi->vtbl_slots) &&
 579             req->vol_id != UBI_VOL_NUM_AUTO)
 580                 goto bad;
 581
 582         if (req->alignment == 0)
 583                 goto bad;
 584
 585         if (req->bytes == 0)
 586                 goto bad;
 587
 588         if (req->vol_type != UBI_DYNAMIC_VOLUME &&
 589             req->vol_type != UBI_STATIC_VOLUME)
 590                 goto bad;
 591
 592         if (req->alignment > ubi->leb_size)
 593                 goto bad;
 594
 595         n = req->alignment & (ubi->min_io_size - 1);
 596         if (req->alignment != 1 && n)
 597                 goto bad;
 598
 599         if (req->name_len > UBI_VOL_NAME_MAX) {
 600                 err = -ENAMETOOLONG;
 601                 goto bad;
 602         }
 603
 604         n = strnlen(req->name, req->name_len + 1);
 605         if (n != req->name_len)
 606                 goto bad;
 607
 608         return 0;
 609
 610 bad:
 611         dbg_err("bad volume creation request");
 612         ubi_dbg_dump_mkvol_req(req);
 613         return err;
 614 }
 615
 616 /**
 617  * verify_rsvol_req - verify volume re-size request.
 618  * @ubi: UBI device description object
 619  * @req: the request to check
 620  *
 621  * This function returns zero if the request is correct, and %-EINVAL if not.
 622  */
 623 static int verify_rsvol_req(const struct ubi_device *ubi,
 624                             const struct ubi_rsvol_req *req)
 625 {
 626         if (req->bytes <= 0)
 627                 return -EINVAL;
 628
 629         if (req->vol_id < 0 || req->vol_id >= ubi->vtbl_slots)
 630                 return -EINVAL;
 631
 632         return 0;
 633 }
 634
 635 /**
 636  * rename_volumes - rename UBI volumes.
 637  * @ubi: UBI device description object
 638  * @req: volumes re-name request
 639  *
 640  * This is a helper function for the volume re-name IOCTL which validates the
 641  * the request, opens the volume and calls corresponding volumes management
 642  * function. Returns zero in case of success and a negative error code in case
 643  * of failure.
 644  */
 645 static int rename_volumes(struct ubi_device *ubi,
 646                           struct ubi_rnvol_req *req)
 647 {
 648         int i, n, err;
 649         struct list_head rename_list;
 650         struct ubi_rename_entry *re, *re1;
 651
 652         if (req->count < 0 || req->count > UBI_MAX_RNVOL)
 653                 return -EINVAL;
 654
 655         if (req->count == 0)
 656                 return 0;
 657
 658         /* Validate volume IDs and names in the request */
 659         for (i = 0; i < req->count; i++) {
 660                 if (req->ents[i].vol_id < 0 ||
 661                     req->ents[i].vol_id >= ubi->vtbl_slots)
 662                         return -EINVAL;
 663                 if (req->ents[i].name_len < 0)
 664                         return -EINVAL;
 665                 if (req->ents[i].name_len > UBI_VOL_NAME_MAX)
 666                         return -ENAMETOOLONG;
 667                 req->ents[i].name[req->ents[i].name_len] = '\0';
 668                 n = strlen(req->ents[i].name);
 669                 if (n != req->ents[i].name_len)
 670                         err = -EINVAL;
 671         }
 672
 673         /* Make sure volume IDs and names are unique */
 674         for (i = 0; i < req->count - 1; i++) {
 675                 for (n = i + 1; n < req->count; n++) {
 676                         if (req->ents[i].vol_id == req->ents[n].vol_id) {
 677                                 dbg_err("duplicated volume id %d",
 678                                         req->ents[i].vol_id);
 679                                 return -EINVAL;
 680                         }
 681                         if (!strcmp(req->ents[i].name, req->ents[n].name)) {
 682                                 dbg_err("duplicated volume name \"%s\"",
 683                                         req->ents[i].name);
 684                                 return -EINVAL;
 685                         }
 686                 }
 687         }
 688
 689         /* Create the re-name list */
 690         INIT_LIST_HEAD(&rename_list);
 691         for (i = 0; i < req->count; i++) {
 692                 int vol_id = req->ents[i].vol_id;
 693                 int name_len = req->ents[i].name_len;
 694                 const char *name = req->ents[i].name;
 695
 696                 re = kzalloc(sizeof(struct ubi_rename_entry), GFP_KERNEL);
 697                 if (!re) {
 698                         err = -ENOMEM;
 699                         goto out_free;
 700                 }
 701
 702                 re->desc = ubi_open_volume(ubi->ubi_num, vol_id, UBI_EXCLUSIVE);
 703                 if (IS_ERR(re->desc)) {
 704                         err = PTR_ERR(re->desc);
 705                         dbg_err("cannot open volume %d, error %d", vol_id, err);
 706                         kfree(re);
 707                         goto out_free;
 708                 }
 709
 710                 /* Skip this re-naming if the name does not really change */
 711                 if (re->desc->vol->name_len == name_len &&
 712                     !memcmp(re->desc->vol->name, name, name_len)) {
 713                         ubi_close_volume(re->desc);
 714                         kfree(re);
 715                         continue;
 716                 }
 717
 718                 re->new_name_len = name_len;
 719                 memcpy(re->new_name, name, name_len);
 720                 list_add_tail(&re->list, &rename_list);
 721                 dbg_msg("will rename volume %d from \"%s\" to \"%s\"",
 722                         vol_id, re->desc->vol->name, name);
 723         }
 724
 725         if (list_empty(&rename_list))
 726                 return 0;
 727
 728         /* Find out the volumes which have to be removed */
 729         list_for_each_entry(re, &rename_list, list) {
 730                 struct ubi_volume_desc *desc;
 731                 int no_remove_needed = 0;
 732
 733                 /*
 734                  * Volume @re->vol_id is going to be re-named to
 735                  * @re->new_name, while its current name is @name. If a volume
 736                  * with name @re->new_name currently exists, it has to be
 737                  * removed, unless it is also re-named in the request (@req).
 738                  */
 739                 list_for_each_entry(re1, &rename_list, list) {
 740                         if (re->new_name_len == re1->desc->vol->name_len &&
 741                             !memcmp(re->new_name, re1->desc->vol->name,
 742                                     re1->desc->vol->name_len)) {
 743                                 no_remove_needed = 1;
 744                                 break;
 745                         }
 746                 }
 747
 748                 if (no_remove_needed)
 749                         continue;
 750
 751                 /*
 752                  * It seems we need to remove volume with name @re->new_name,
 753                  * if it exists.
 754                  */
 755                 desc = ubi_open_volume_nm(ubi->ubi_num, re->new_name,
 756                                           UBI_EXCLUSIVE);
 757                 if (IS_ERR(desc)) {
 758                         err = PTR_ERR(desc);
 759                         if (err == -ENODEV)
 760                                 /* Re-naming into a non-existing volume name */
 761                                 continue;
 762
 763                         /* The volume exists but busy, or an error occurred */
 764                         dbg_err("cannot open volume \"%s\", error %d",
 765                                 re->new_name, err);
 766                         goto out_free;
 767                 }
 768
 769                 re = kzalloc(sizeof(struct ubi_rename_entry), GFP_KERNEL);
 770                 if (!re) {
 771                         err = -ENOMEM;
 772                         ubi_close_volume(desc);
 773                         goto out_free;
 774                 }
 775
 776                 re->remove = 1;
 777                 re->desc = desc;
 778                 list_add(&re->list, &rename_list);
 779                 dbg_msg("will remove volume %d, name \"%s\"",
 780                         re->desc->vol->vol_id, re->desc->vol->name);
 781         }
 782
 783         mutex_lock(&ubi->volumes_mutex);
 784         err = ubi_rename_volumes(ubi, &rename_list);
 785         mutex_unlock(&ubi->volumes_mutex);
 786
 787 out_free:
 788         list_for_each_entry_safe(re, re1, &rename_list, list) {
 789                 ubi_close_volume(re->desc);
 790                 list_del(&re->list);
 791                 kfree(re);
 792         }
 793         return err;
 794 }
 795
 796 static long ubi_cdev_ioctl(struct file *file, unsigned int cmd,
 797                            unsigned long arg)
 798 {
 799         int err = 0;
 800         struct ubi_device *ubi;
 801         struct ubi_volume_desc *desc;
 802         void __user *argp = (void __user *)arg;
 803
 804         if (!capable(CAP_SYS_RESOURCE))
 805                 return -EPERM;
 806
 807         ubi = ubi_get_by_major(imajor(file->f_mapping->host));
 808         if (!ubi)
 809                 return -ENODEV;
 810
 811         switch (cmd) {
 812         /* Create volume command */
 813         case UBI_IOCMKVOL:
 814         {
 815                 struct ubi_mkvol_req req;
 816
 817                 dbg_gen("create volume");
 818                 err = copy_from_user(&req, argp, sizeof(struct ubi_mkvol_req));
 819                 if (err) {
 820                         err = -EFAULT;
 821                         break;
 822                 }
 823
 824                 req.name[req.name_len] = '\0';
 825                 err = verify_mkvol_req(ubi, &req);
 826                 if (err)
 827                         break;
 828
 829                 mutex_lock(&ubi->volumes_mutex);
 830                 err = ubi_create_volume(ubi, &req);
 831                 mutex_unlock(&ubi->volumes_mutex);
 832                 if (err)
 833                         break;
 834
 835                 err = put_user(req.vol_id, (__user int32_t *)argp);
 836                 if (err)
 837                         err = -EFAULT;
 838
 839                 break;
 840         }
 841
 842         /* Remove volume command */
 843         case UBI_IOCRMVOL:
 844         {
 845                 int vol_id;
 846
 847                 dbg_gen("remove volume");
 848                 err = get_user(vol_id, (__user int32_t *)argp);
 849                 if (err) {
 850                         err = -EFAULT;
 851                         break;
 852                 }
 853
 854                 desc = ubi_open_volume(ubi->ubi_num, vol_id, UBI_EXCLUSIVE);
 855                 if (IS_ERR(desc)) {
 856                         err = PTR_ERR(desc);
 857                         break;
 858                 }
 859
 860                 mutex_lock(&ubi->volumes_mutex);
 861                 err = ubi_remove_volume(desc, 0);
 862                 mutex_unlock(&ubi->volumes_mutex);
 863
 864                 /*
 865                  * The volume is deleted (unless an error occurred), and the
 866                  * 'struct ubi_volume' object will be freed when
 867                  * 'ubi_close_volume()' will call 'put_device()'.
 868                  */
 869                 ubi_close_volume(desc);
 870                 break;
 871         }
 872
 873         /* Re-size volume command */
 874         case UBI_IOCRSVOL:
 875         {
 876                 int pebs;
 877                 struct ubi_rsvol_req req;
 878
 879                 dbg_gen("re-size volume");
 880                 err = copy_from_user(&req, argp, sizeof(struct ubi_rsvol_req));
 881                 if (err) {
 882                         err = -EFAULT;
 883                         break;
 884                 }
 885
 886                 err = verify_rsvol_req(ubi, &req);
 887                 if (err)
 888                         break;
 889
 890                 desc = ubi_open_volume(ubi->ubi_num, req.vol_id, UBI_EXCLUSIVE);
 891                 if (IS_ERR(desc)) {
 892                         err = PTR_ERR(desc);
 893                         break;
 894                 }
 895
 896                 pebs = div_u64(req.bytes + desc->vol->usable_leb_size - 1,
 897                                desc->vol->usable_leb_size);
 898
 899                 mutex_lock(&ubi->volumes_mutex);
 900                 err = ubi_resize_volume(desc, pebs);
 901                 mutex_unlock(&ubi->volumes_mutex);
 902                 ubi_close_volume(desc);
 903                 break;
 904         }
 905
 906         /* Re-name volumes command */
 907         case UBI_IOCRNVOL:
 908         {
 909                 struct ubi_rnvol_req *req;
 910
 911                 dbg_msg("re-name volumes");
 912                 req = kmalloc(sizeof(struct ubi_rnvol_req), GFP_KERNEL);
 913                 if (!req) {
 914                         err = -ENOMEM;
 915                         break;
 916                 };
 917
 918                 err = copy_from_user(req, argp, sizeof(struct ubi_rnvol_req));
 919                 if (err) {
 920                         err = -EFAULT;
 921                         kfree(req);
 922                         break;
 923                 }
 924
 925                 mutex_lock(&ubi->mult_mutex);
 926                 err = rename_volumes(ubi, req);
 927                 mutex_unlock(&ubi->mult_mutex);
 928                 kfree(req);
 929                 break;
 930         }
 931
 932         default:
 933                 err = -ENOTTY;
 934                 break;
 935         }
 936
 937         ubi_put_device(ubi);
 938         return err;
 939 }
 940
 941 static long ctrl_cdev_ioctl(struct file *file, unsigned int cmd,
 942                             unsigned long arg)
 943 {
 944         int err = 0;
 945         void __user *argp = (void __user *)arg;
 946
 947         if (!capable(CAP_SYS_RESOURCE))
 948                 return -EPERM;
 949
 950         switch (cmd) {
 951         /* Attach an MTD device command */
 952         case UBI_IOCATT:
 953         {
 954                 struct ubi_attach_req req;
 955                 struct mtd_info *mtd;
 956
 957                 dbg_gen("attach MTD device");
 958                 err = copy_from_user(&req, argp, sizeof(struct ubi_attach_req));
 959                 if (err) {
 960                         err = -EFAULT;
 961                         break;
 962                 }
 963
 964                 if (req.mtd_num < 0 ||
 965                     (req.ubi_num < 0 && req.ubi_num != UBI_DEV_NUM_AUTO)) {
 966                         err = -EINVAL;
 967                         break;
 968                 }
 969
 970                 mtd = get_mtd_device(NULL, req.mtd_num);
 971                 if (IS_ERR(mtd)) {
 972                         err = PTR_ERR(mtd);
 973                         break;
 974                 }
 975
 976                 /*
 977                  * Note, further request verification is done by
 978                  * 'ubi_attach_mtd_dev()'.
 979                  */
 980                 mutex_lock(&ubi_devices_mutex);
 981                 err = ubi_attach_mtd_dev(mtd, req.ubi_num, req.vid_hdr_offset);
 982                 mutex_unlock(&ubi_devices_mutex);
 983                 if (err < 0)
 984                         put_mtd_device(mtd);
 985                 else
 986                         /* @err contains UBI device number */
 987                         err = put_user(err, (__user int32_t *)argp);
 988
 989                 break;
 990         }
 991
 992         /* Detach an MTD device command */
 993         case UBI_IOCDET:
 994         {
 995                 int ubi_num;
 996
 997                 dbg_gen("dettach MTD device");
 998                 err = get_user(ubi_num, (__user int32_t *)argp);
 999                 if (err) {
1000                         err = -EFAULT;
1001                         break;
1002                 }
1003
1004                 mutex_lock(&ubi_devices_mutex);
1005                 err = ubi_detach_mtd_dev(ubi_num, 0);
1006                 mutex_unlock(&ubi_devices_mutex);
1007                 break;
1008         }
1009
1010         default:
1011                 err = -ENOTTY;
1012                 break;
1013         }
1014
1015         return err;
1016 }
1017
1018 #ifdef CONFIG_COMPAT
1019 static long vol_cdev_compat_ioctl(struct file *file, unsigned int cmd,
1020                                   unsigned long arg)
1021 {
1022         unsigned long translated_arg = (unsigned long)compat_ptr(arg);
1023
1024         return vol_cdev_ioctl(file, cmd, translated_arg);
1025 }
1026
1027 static long ubi_cdev_compat_ioctl(struct file *file, unsigned int cmd,
1028                                   unsigned long arg)
1029 {
1030         unsigned long translated_arg = (unsigned long)compat_ptr(arg);
1031
1032         return ubi_cdev_ioctl(file, cmd, translated_arg);
1033 }
1034
1035 static long ctrl_cdev_compat_ioctl(struct file *file, unsigned int cmd,
1036                                    unsigned long arg)
1037 {
1038         unsigned long translated_arg = (unsigned long)compat_ptr(arg);
1039
1040         return ctrl_cdev_ioctl(file, cmd, translated_arg);
1041 }
1042 #else
1043 #define vol_cdev_compat_ioctl  NULL
1044 #define ubi_cdev_compat_ioctl  NULL
1045 #define ctrl_cdev_compat_ioctl NULL
1046 #endif
1047
1048 /* UBI volume character device operations */
1049 const struct file_operations ubi_vol_cdev_operations = {
1050         .owner          = THIS_MODULE,
1051         .open           = vol_cdev_open,
1052         .release        = vol_cdev_release,
1053         .llseek         = vol_cdev_llseek,
1054         .read           = vol_cdev_read,
1055         .write          = vol_cdev_write,
1056         .unlocked_ioctl = vol_cdev_ioctl,
1057         .compat_ioctl   = vol_cdev_compat_ioctl,
1058 };
1059
1060 /* UBI character device operations */
1061 const struct file_operations ubi_cdev_operations = {
1062         .owner          = THIS_MODULE,
1063         .llseek         = no_llseek,
1064         .unlocked_ioctl = ubi_cdev_ioctl,
1065         .compat_ioctl   = ubi_cdev_compat_ioctl,
1066 };
1067
1068 /* UBI control character device operations */
1069 const struct file_operations ubi_ctrl_cdev_operations = {
1070         .owner          = THIS_MODULE,
1071         .unlocked_ioctl = ctrl_cdev_ioctl,
1072         .compat_ioctl   = ctrl_cdev_compat_ioctl,
1073 };