1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (c) International Business Machines Corp., 2006 4 * 5 * Author: Artem Bityutskiy (Битюцкий Артём) 6 */ 7 8 /* 9 * This file includes implementation of UBI character device operations. 10 * 11 * There are two kinds of character devices in UBI: UBI character devices and 12 * UBI volume character devices. UBI character devices allow users to 13 * manipulate whole volumes: create, remove, and re-size them. Volume character 14 * devices provide volume I/O capabilities. 15 * 16 * Major and minor numbers are assigned dynamically to both UBI and volume 17 * character devices. 18 * 19 * Well, there is the third kind of character devices - the UBI control 20 * character device, which allows to manipulate by UBI devices - create and 21 * delete them. In other words, it is used for attaching and detaching MTD 22 * devices. 23 */ 24 25 #include <linux/module.h> 26 #include <linux/stat.h> 27 #include <linux/slab.h> 28 #include <linux/ioctl.h> 29 #include <linux/capability.h> 30 #include <linux/uaccess.h> 31 #include <linux/compat.h> 32 #include <linux/math64.h> 33 #include <mtd/ubi-user.h> 34 #include "ubi.h" 35 36 /** 37 * get_exclusive - get exclusive access to an UBI volume. 38 * @desc: volume descriptor 39 * 40 * This function changes UBI volume open mode to "exclusive". Returns previous 41 * mode value (positive integer) in case of success and a negative error code 42 * in case of failure. 43 */ 44 static int get_exclusive(struct ubi_volume_desc *desc) 45 { 46 int users, err; 47 struct ubi_volume *vol = desc->vol; 48 49 spin_lock(&vol->ubi->volumes_lock); 50 users = vol->readers + vol->writers + vol->exclusive + vol->metaonly; 51 ubi_assert(users > 0); 52 if (users > 1) { 53 ubi_err(vol->ubi, "%d users for volume %d", users, vol->vol_id); 54 err = -EBUSY; 55 } else { 56 vol->readers = vol->writers = vol->metaonly = 0; 57 vol->exclusive = 1; 58 err = desc->mode; 59 desc->mode = UBI_EXCLUSIVE; 60 } 61 spin_unlock(&vol->ubi->volumes_lock); 62 63 return err; 64 } 65 66 /** 67 * revoke_exclusive - revoke exclusive mode. 68 * @desc: volume descriptor 69 * @mode: new mode to switch to 70 */ 71 static void revoke_exclusive(struct ubi_volume_desc *desc, int mode) 72 { 73 struct ubi_volume *vol = desc->vol; 74 75 spin_lock(&vol->ubi->volumes_lock); 76 ubi_assert(vol->readers == 0 && vol->writers == 0 && vol->metaonly == 0); 77 ubi_assert(vol->exclusive == 1 && desc->mode == UBI_EXCLUSIVE); 78 vol->exclusive = 0; 79 if (mode == UBI_READONLY) 80 vol->readers = 1; 81 else if (mode == UBI_READWRITE) 82 vol->writers = 1; 83 else if (mode == UBI_METAONLY) 84 vol->metaonly = 1; 85 else 86 vol->exclusive = 1; 87 spin_unlock(&vol->ubi->volumes_lock); 88 89 desc->mode = mode; 90 } 91 92 static int vol_cdev_open(struct inode *inode, struct file *file) 93 { 94 struct ubi_volume_desc *desc; 95 int vol_id = iminor(inode) - 1, mode, ubi_num; 96 97 ubi_num = ubi_major2num(imajor(inode)); 98 if (ubi_num < 0) 99 return ubi_num; 100 101 if (file->f_mode & FMODE_WRITE) 102 mode = UBI_READWRITE; 103 else 104 mode = UBI_READONLY; 105 106 dbg_gen("open device %d, volume %d, mode %d", 107 ubi_num, vol_id, mode); 108 109 desc = ubi_open_volume(ubi_num, vol_id, mode); 110 if (IS_ERR(desc)) 111 return PTR_ERR(desc); 112 113 file->private_data = desc; 114 return 0; 115 } 116 117 static int vol_cdev_release(struct inode *inode, struct file *file) 118 { 119 struct ubi_volume_desc *desc = file->private_data; 120 struct ubi_volume *vol = desc->vol; 121 122 dbg_gen("release device %d, volume %d, mode %d", 123 vol->ubi->ubi_num, vol->vol_id, desc->mode); 124 125 if (vol->updating) { 126 ubi_warn(vol->ubi, "update of volume %d not finished, volume is damaged", 127 vol->vol_id); 128 ubi_assert(!vol->changing_leb); 129 vol->updating = 0; 130 vfree(vol->upd_buf); 131 } else if (vol->changing_leb) { 132 dbg_gen("only %lld of %lld bytes received for atomic LEB change for volume %d:%d, cancel", 133 vol->upd_received, vol->upd_bytes, vol->ubi->ubi_num, 134 vol->vol_id); 135 vol->changing_leb = 0; 136 vfree(vol->upd_buf); 137 } 138 139 ubi_close_volume(desc); 140 return 0; 141 } 142 143 static loff_t vol_cdev_llseek(struct file *file, loff_t offset, int origin) 144 { 145 struct ubi_volume_desc *desc = file->private_data; 146 struct ubi_volume *vol = desc->vol; 147 148 if (vol->updating) { 149 /* Update is in progress, seeking is prohibited */ 150 ubi_err(vol->ubi, "updating"); 151 return -EBUSY; 152 } 153 154 return fixed_size_llseek(file, offset, origin, vol->used_bytes); 155 } 156 157 static int vol_cdev_fsync(struct file *file, loff_t start, loff_t end, 158 int datasync) 159 { 160 struct ubi_volume_desc *desc = file->private_data; 161 struct ubi_device *ubi = desc->vol->ubi; 162 struct inode *inode = file_inode(file); 163 int err; 164 inode_lock(inode); 165 err = ubi_sync(ubi->ubi_num); 166 inode_unlock(inode); 167 return err; 168 } 169 170 171 static ssize_t vol_cdev_read(struct file *file, __user char *buf, size_t count, 172 loff_t *offp) 173 { 174 struct ubi_volume_desc *desc = file->private_data; 175 struct ubi_volume *vol = desc->vol; 176 struct ubi_device *ubi = vol->ubi; 177 int err, lnum, off, len, tbuf_size; 178 size_t count_save = count; 179 void *tbuf; 180 181 dbg_gen("read %zd bytes from offset %lld of volume %d", 182 count, *offp, vol->vol_id); 183 184 if (vol->updating) { 185 ubi_err(vol->ubi, "updating"); 186 return -EBUSY; 187 } 188 if (vol->upd_marker) { 189 ubi_err(vol->ubi, "damaged volume, update marker is set"); 190 return -EBADF; 191 } 192 if (*offp == vol->used_bytes || count == 0) 193 return 0; 194 195 if (vol->corrupted) 196 dbg_gen("read from corrupted volume %d", vol->vol_id); 197 198 if (*offp + count > vol->used_bytes) 199 count_save = count = vol->used_bytes - *offp; 200 201 tbuf_size = vol->usable_leb_size; 202 if (count < tbuf_size) 203 tbuf_size = ALIGN(count, ubi->min_io_size); 204 tbuf = vmalloc(tbuf_size); 205 if (!tbuf) 206 return -ENOMEM; 207 208 len = count > tbuf_size ? tbuf_size : count; 209 lnum = div_u64_rem(*offp, vol->usable_leb_size, &off); 210 211 do { 212 cond_resched(); 213 214 if (off + len >= vol->usable_leb_size) 215 len = vol->usable_leb_size - off; 216 217 err = ubi_eba_read_leb(ubi, vol, lnum, tbuf, off, len, 0); 218 if (err) 219 break; 220 221 off += len; 222 if (off == vol->usable_leb_size) { 223 lnum += 1; 224 off -= vol->usable_leb_size; 225 } 226 227 count -= len; 228 *offp += len; 229 230 err = copy_to_user(buf, tbuf, len); 231 if (err) { 232 err = -EFAULT; 233 break; 234 } 235 236 buf += len; 237 len = count > tbuf_size ? tbuf_size : count; 238 } while (count); 239 240 vfree(tbuf); 241 return err ? err : count_save - count; 242 } 243 244 /* 245 * This function allows to directly write to dynamic UBI volumes, without 246 * issuing the volume update operation. 247 */ 248 static ssize_t vol_cdev_direct_write(struct file *file, const char __user *buf, 249 size_t count, loff_t *offp) 250 { 251 struct ubi_volume_desc *desc = file->private_data; 252 struct ubi_volume *vol = desc->vol; 253 struct ubi_device *ubi = vol->ubi; 254 int lnum, off, len, tbuf_size, err = 0; 255 size_t count_save = count; 256 char *tbuf; 257 258 if (!vol->direct_writes) 259 return -EPERM; 260 261 dbg_gen("requested: write %zd bytes to offset %lld of volume %u", 262 count, *offp, vol->vol_id); 263 264 if (vol->vol_type == UBI_STATIC_VOLUME) 265 return -EROFS; 266 267 lnum = div_u64_rem(*offp, vol->usable_leb_size, &off); 268 if (off & (ubi->min_io_size - 1)) { 269 ubi_err(ubi, "unaligned position"); 270 return -EINVAL; 271 } 272 273 if (*offp + count > vol->used_bytes) 274 count_save = count = vol->used_bytes - *offp; 275 276 /* We can write only in fractions of the minimum I/O unit */ 277 if (count & (ubi->min_io_size - 1)) { 278 ubi_err(ubi, "unaligned write length"); 279 return -EINVAL; 280 } 281 282 tbuf_size = vol->usable_leb_size; 283 if (count < tbuf_size) 284 tbuf_size = ALIGN(count, ubi->min_io_size); 285 tbuf = vmalloc(tbuf_size); 286 if (!tbuf) 287 return -ENOMEM; 288 289 len = count > tbuf_size ? tbuf_size : count; 290 291 while (count) { 292 cond_resched(); 293 294 if (off + len >= vol->usable_leb_size) 295 len = vol->usable_leb_size - off; 296 297 err = copy_from_user(tbuf, buf, len); 298 if (err) { 299 err = -EFAULT; 300 break; 301 } 302 303 err = ubi_eba_write_leb(ubi, vol, lnum, tbuf, off, len); 304 if (err) 305 break; 306 307 off += len; 308 if (off == vol->usable_leb_size) { 309 lnum += 1; 310 off -= vol->usable_leb_size; 311 } 312 313 count -= len; 314 *offp += len; 315 buf += len; 316 len = count > tbuf_size ? tbuf_size : count; 317 } 318 319 vfree(tbuf); 320 return err ? err : count_save - count; 321 } 322 323 static ssize_t vol_cdev_write(struct file *file, const char __user *buf, 324 size_t count, loff_t *offp) 325 { 326 int err = 0; 327 struct ubi_volume_desc *desc = file->private_data; 328 struct ubi_volume *vol = desc->vol; 329 struct ubi_device *ubi = vol->ubi; 330 331 if (!vol->updating && !vol->changing_leb) 332 return vol_cdev_direct_write(file, buf, count, offp); 333 334 if (vol->updating) 335 err = ubi_more_update_data(ubi, vol, buf, count); 336 else 337 err = ubi_more_leb_change_data(ubi, vol, buf, count); 338 339 if (err < 0) { 340 ubi_err(ubi, "cannot accept more %zd bytes of data, error %d", 341 count, err); 342 return err; 343 } 344 345 if (err) { 346 /* 347 * The operation is finished, @err contains number of actually 348 * written bytes. 349 */ 350 count = err; 351 352 if (vol->changing_leb) { 353 revoke_exclusive(desc, UBI_READWRITE); 354 return count; 355 } 356 357 /* 358 * We voluntarily do not take into account the skip_check flag 359 * as we want to make sure what we wrote was correctly written. 360 */ 361 err = ubi_check_volume(ubi, vol->vol_id); 362 if (err < 0) 363 return err; 364 365 if (err) { 366 ubi_warn(ubi, "volume %d on UBI device %d is corrupted", 367 vol->vol_id, ubi->ubi_num); 368 vol->corrupted = 1; 369 } 370 vol->checked = 1; 371 ubi_volume_notify(ubi, vol, UBI_VOLUME_UPDATED); 372 revoke_exclusive(desc, UBI_READWRITE); 373 } 374 375 return count; 376 } 377 378 static long vol_cdev_ioctl(struct file *file, unsigned int cmd, 379 unsigned long arg) 380 { 381 int err = 0; 382 struct ubi_volume_desc *desc = file->private_data; 383 struct ubi_volume *vol = desc->vol; 384 struct ubi_device *ubi = vol->ubi; 385 void __user *argp = (void __user *)arg; 386 387 switch (cmd) { 388 /* Volume update command */ 389 case UBI_IOCVOLUP: 390 { 391 int64_t bytes, rsvd_bytes; 392 393 if (!capable(CAP_SYS_RESOURCE)) { 394 err = -EPERM; 395 break; 396 } 397 398 err = copy_from_user(&bytes, argp, sizeof(int64_t)); 399 if (err) { 400 err = -EFAULT; 401 break; 402 } 403 404 if (desc->mode == UBI_READONLY) { 405 err = -EROFS; 406 break; 407 } 408 409 rsvd_bytes = (long long)vol->reserved_pebs * 410 vol->usable_leb_size; 411 if (bytes < 0 || bytes > rsvd_bytes) { 412 err = -EINVAL; 413 break; 414 } 415 416 err = get_exclusive(desc); 417 if (err < 0) 418 break; 419 420 err = ubi_start_update(ubi, vol, bytes); 421 if (bytes == 0) { 422 ubi_volume_notify(ubi, vol, UBI_VOLUME_UPDATED); 423 revoke_exclusive(desc, UBI_READWRITE); 424 } 425 break; 426 } 427 428 /* Atomic logical eraseblock change command */ 429 case UBI_IOCEBCH: 430 { 431 struct ubi_leb_change_req req; 432 433 err = copy_from_user(&req, argp, 434 sizeof(struct ubi_leb_change_req)); 435 if (err) { 436 err = -EFAULT; 437 break; 438 } 439 440 if (desc->mode == UBI_READONLY || 441 vol->vol_type == UBI_STATIC_VOLUME) { 442 err = -EROFS; 443 break; 444 } 445 446 /* Validate the request */ 447 err = -EINVAL; 448 if (!ubi_leb_valid(vol, req.lnum) || 449 req.bytes < 0 || req.bytes > vol->usable_leb_size) 450 break; 451 452 err = get_exclusive(desc); 453 if (err < 0) 454 break; 455 456 err = ubi_start_leb_change(ubi, vol, &req); 457 if (req.bytes == 0) 458 revoke_exclusive(desc, UBI_READWRITE); 459 break; 460 } 461 462 /* Logical eraseblock erasure command */ 463 case UBI_IOCEBER: 464 { 465 int32_t lnum; 466 467 err = get_user(lnum, (__user int32_t *)argp); 468 if (err) { 469 err = -EFAULT; 470 break; 471 } 472 473 if (desc->mode == UBI_READONLY || 474 vol->vol_type == UBI_STATIC_VOLUME) { 475 err = -EROFS; 476 break; 477 } 478 479 if (!ubi_leb_valid(vol, lnum)) { 480 err = -EINVAL; 481 break; 482 } 483 484 dbg_gen("erase LEB %d:%d", vol->vol_id, lnum); 485 err = ubi_eba_unmap_leb(ubi, vol, lnum); 486 if (err) 487 break; 488 489 err = ubi_wl_flush(ubi, UBI_ALL, UBI_ALL); 490 break; 491 } 492 493 /* Logical eraseblock map command */ 494 case UBI_IOCEBMAP: 495 { 496 struct ubi_map_req req; 497 498 err = copy_from_user(&req, argp, sizeof(struct ubi_map_req)); 499 if (err) { 500 err = -EFAULT; 501 break; 502 } 503 err = ubi_leb_map(desc, req.lnum); 504 break; 505 } 506 507 /* Logical eraseblock un-map command */ 508 case UBI_IOCEBUNMAP: 509 { 510 int32_t lnum; 511 512 err = get_user(lnum, (__user int32_t *)argp); 513 if (err) { 514 err = -EFAULT; 515 break; 516 } 517 err = ubi_leb_unmap(desc, lnum); 518 break; 519 } 520 521 /* Check if logical eraseblock is mapped command */ 522 case UBI_IOCEBISMAP: 523 { 524 int32_t lnum; 525 526 err = get_user(lnum, (__user int32_t *)argp); 527 if (err) { 528 err = -EFAULT; 529 break; 530 } 531 err = ubi_is_mapped(desc, lnum); 532 break; 533 } 534 535 /* Set volume property command */ 536 case UBI_IOCSETVOLPROP: 537 { 538 struct ubi_set_vol_prop_req req; 539 540 err = copy_from_user(&req, argp, 541 sizeof(struct ubi_set_vol_prop_req)); 542 if (err) { 543 err = -EFAULT; 544 break; 545 } 546 switch (req.property) { 547 case UBI_VOL_PROP_DIRECT_WRITE: 548 mutex_lock(&ubi->device_mutex); 549 desc->vol->direct_writes = !!req.value; 550 mutex_unlock(&ubi->device_mutex); 551 break; 552 default: 553 err = -EINVAL; 554 break; 555 } 556 break; 557 } 558 559 /* Create a R/O block device on top of the UBI volume */ 560 case UBI_IOCVOLCRBLK: 561 { 562 struct ubi_volume_info vi; 563 564 ubi_get_volume_info(desc, &vi); 565 err = ubiblock_create(&vi); 566 break; 567 } 568 569 /* Remove the R/O block device */ 570 case UBI_IOCVOLRMBLK: 571 { 572 struct ubi_volume_info vi; 573 574 ubi_get_volume_info(desc, &vi); 575 err = ubiblock_remove(&vi); 576 break; 577 } 578 579 default: 580 err = -ENOTTY; 581 break; 582 } 583 return err; 584 } 585 586 /** 587 * verify_mkvol_req - verify volume creation request. 588 * @ubi: UBI device description object 589 * @req: the request to check 590 * 591 * This function zero if the request is correct, and %-EINVAL if not. 592 */ 593 static int verify_mkvol_req(const struct ubi_device *ubi, 594 const struct ubi_mkvol_req *req) 595 { 596 int n, err = -EINVAL; 597 598 if (req->bytes < 0 || req->alignment < 0 || req->vol_type < 0 || 599 req->name_len < 0) 600 goto bad; 601 602 if ((req->vol_id < 0 || req->vol_id >= ubi->vtbl_slots) && 603 req->vol_id != UBI_VOL_NUM_AUTO) 604 goto bad; 605 606 if (req->alignment == 0) 607 goto bad; 608 609 if (req->bytes == 0) 610 goto bad; 611 612 if (req->vol_type != UBI_DYNAMIC_VOLUME && 613 req->vol_type != UBI_STATIC_VOLUME) 614 goto bad; 615 616 if (req->flags & ~UBI_VOL_VALID_FLGS) 617 goto bad; 618 619 if (req->flags & UBI_VOL_SKIP_CRC_CHECK_FLG && 620 req->vol_type != UBI_STATIC_VOLUME) 621 goto bad; 622 623 if (req->alignment > ubi->leb_size) 624 goto bad; 625 626 n = req->alignment & (ubi->min_io_size - 1); 627 if (req->alignment != 1 && n) 628 goto bad; 629 630 if (!req->name[0] || !req->name_len) 631 goto bad; 632 633 if (req->name_len > UBI_VOL_NAME_MAX) { 634 err = -ENAMETOOLONG; 635 goto bad; 636 } 637 638 n = strnlen(req->name, req->name_len + 1); 639 if (n != req->name_len) 640 goto bad; 641 642 return 0; 643 644 bad: 645 ubi_err(ubi, "bad volume creation request"); 646 ubi_dump_mkvol_req(req); 647 return err; 648 } 649 650 /** 651 * verify_rsvol_req - verify volume re-size request. 652 * @ubi: UBI device description object 653 * @req: the request to check 654 * 655 * This function returns zero if the request is correct, and %-EINVAL if not. 656 */ 657 static int verify_rsvol_req(const struct ubi_device *ubi, 658 const struct ubi_rsvol_req *req) 659 { 660 if (req->bytes <= 0) 661 return -EINVAL; 662 663 if (req->vol_id < 0 || req->vol_id >= ubi->vtbl_slots) 664 return -EINVAL; 665 666 return 0; 667 } 668 669 /** 670 * rename_volumes - rename UBI volumes. 671 * @ubi: UBI device description object 672 * @req: volumes re-name request 673 * 674 * This is a helper function for the volume re-name IOCTL which validates the 675 * request, opens the volume and calls corresponding volumes management 676 * function. Returns zero in case of success and a negative error code in case 677 * of failure. 678 */ 679 static int rename_volumes(struct ubi_device *ubi, 680 struct ubi_rnvol_req *req) 681 { 682 int i, n, err; 683 struct list_head rename_list; 684 struct ubi_rename_entry *re, *re1; 685 686 if (req->count < 0 || req->count > UBI_MAX_RNVOL) 687 return -EINVAL; 688 689 if (req->count == 0) 690 return 0; 691 692 /* Validate volume IDs and names in the request */ 693 for (i = 0; i < req->count; i++) { 694 if (req->ents[i].vol_id < 0 || 695 req->ents[i].vol_id >= ubi->vtbl_slots) 696 return -EINVAL; 697 if (req->ents[i].name_len < 0) 698 return -EINVAL; 699 if (req->ents[i].name_len > UBI_VOL_NAME_MAX) 700 return -ENAMETOOLONG; 701 req->ents[i].name[req->ents[i].name_len] = '\0'; 702 n = strlen(req->ents[i].name); 703 if (n != req->ents[i].name_len) 704 return -EINVAL; 705 } 706 707 /* Make sure volume IDs and names are unique */ 708 for (i = 0; i < req->count - 1; i++) { 709 for (n = i + 1; n < req->count; n++) { 710 if (req->ents[i].vol_id == req->ents[n].vol_id) { 711 ubi_err(ubi, "duplicated volume id %d", 712 req->ents[i].vol_id); 713 return -EINVAL; 714 } 715 if (!strcmp(req->ents[i].name, req->ents[n].name)) { 716 ubi_err(ubi, "duplicated volume name \"%s\"", 717 req->ents[i].name); 718 return -EINVAL; 719 } 720 } 721 } 722 723 /* Create the re-name list */ 724 INIT_LIST_HEAD(&rename_list); 725 for (i = 0; i < req->count; i++) { 726 int vol_id = req->ents[i].vol_id; 727 int name_len = req->ents[i].name_len; 728 const char *name = req->ents[i].name; 729 730 re = kzalloc(sizeof(struct ubi_rename_entry), GFP_KERNEL); 731 if (!re) { 732 err = -ENOMEM; 733 goto out_free; 734 } 735 736 re->desc = ubi_open_volume(ubi->ubi_num, vol_id, UBI_METAONLY); 737 if (IS_ERR(re->desc)) { 738 err = PTR_ERR(re->desc); 739 ubi_err(ubi, "cannot open volume %d, error %d", 740 vol_id, err); 741 kfree(re); 742 goto out_free; 743 } 744 745 /* Skip this re-naming if the name does not really change */ 746 if (re->desc->vol->name_len == name_len && 747 !memcmp(re->desc->vol->name, name, name_len)) { 748 ubi_close_volume(re->desc); 749 kfree(re); 750 continue; 751 } 752 753 re->new_name_len = name_len; 754 memcpy(re->new_name, name, name_len); 755 list_add_tail(&re->list, &rename_list); 756 dbg_gen("will rename volume %d from \"%s\" to \"%s\"", 757 vol_id, re->desc->vol->name, name); 758 } 759 760 if (list_empty(&rename_list)) 761 return 0; 762 763 /* Find out the volumes which have to be removed */ 764 list_for_each_entry(re, &rename_list, list) { 765 struct ubi_volume_desc *desc; 766 int no_remove_needed = 0; 767 768 /* 769 * Volume @re->vol_id is going to be re-named to 770 * @re->new_name, while its current name is @name. If a volume 771 * with name @re->new_name currently exists, it has to be 772 * removed, unless it is also re-named in the request (@req). 773 */ 774 list_for_each_entry(re1, &rename_list, list) { 775 if (re->new_name_len == re1->desc->vol->name_len && 776 !memcmp(re->new_name, re1->desc->vol->name, 777 re1->desc->vol->name_len)) { 778 no_remove_needed = 1; 779 break; 780 } 781 } 782 783 if (no_remove_needed) 784 continue; 785 786 /* 787 * It seems we need to remove volume with name @re->new_name, 788 * if it exists. 789 */ 790 desc = ubi_open_volume_nm(ubi->ubi_num, re->new_name, 791 UBI_EXCLUSIVE); 792 if (IS_ERR(desc)) { 793 err = PTR_ERR(desc); 794 if (err == -ENODEV) 795 /* Re-naming into a non-existing volume name */ 796 continue; 797 798 /* The volume exists but busy, or an error occurred */ 799 ubi_err(ubi, "cannot open volume \"%s\", error %d", 800 re->new_name, err); 801 goto out_free; 802 } 803 804 re1 = kzalloc(sizeof(struct ubi_rename_entry), GFP_KERNEL); 805 if (!re1) { 806 err = -ENOMEM; 807 ubi_close_volume(desc); 808 goto out_free; 809 } 810 811 re1->remove = 1; 812 re1->desc = desc; 813 list_add(&re1->list, &rename_list); 814 dbg_gen("will remove volume %d, name \"%s\"", 815 re1->desc->vol->vol_id, re1->desc->vol->name); 816 } 817 818 mutex_lock(&ubi->device_mutex); 819 err = ubi_rename_volumes(ubi, &rename_list); 820 mutex_unlock(&ubi->device_mutex); 821 822 out_free: 823 list_for_each_entry_safe(re, re1, &rename_list, list) { 824 ubi_close_volume(re->desc); 825 list_del(&re->list); 826 kfree(re); 827 } 828 return err; 829 } 830 831 static long ubi_cdev_ioctl(struct file *file, unsigned int cmd, 832 unsigned long arg) 833 { 834 int err = 0; 835 struct ubi_device *ubi; 836 struct ubi_volume_desc *desc; 837 void __user *argp = (void __user *)arg; 838 839 if (!capable(CAP_SYS_RESOURCE)) 840 return -EPERM; 841 842 ubi = ubi_get_by_major(imajor(file->f_mapping->host)); 843 if (!ubi) 844 return -ENODEV; 845 846 switch (cmd) { 847 /* Create volume command */ 848 case UBI_IOCMKVOL: 849 { 850 struct ubi_mkvol_req req; 851 852 dbg_gen("create volume"); 853 err = copy_from_user(&req, argp, sizeof(struct ubi_mkvol_req)); 854 if (err) { 855 err = -EFAULT; 856 break; 857 } 858 859 err = verify_mkvol_req(ubi, &req); 860 if (err) 861 break; 862 863 mutex_lock(&ubi->device_mutex); 864 err = ubi_create_volume(ubi, &req); 865 mutex_unlock(&ubi->device_mutex); 866 if (err) 867 break; 868 869 err = put_user(req.vol_id, (__user int32_t *)argp); 870 if (err) 871 err = -EFAULT; 872 873 break; 874 } 875 876 /* Remove volume command */ 877 case UBI_IOCRMVOL: 878 { 879 int vol_id; 880 881 dbg_gen("remove volume"); 882 err = get_user(vol_id, (__user int32_t *)argp); 883 if (err) { 884 err = -EFAULT; 885 break; 886 } 887 888 desc = ubi_open_volume(ubi->ubi_num, vol_id, UBI_EXCLUSIVE); 889 if (IS_ERR(desc)) { 890 err = PTR_ERR(desc); 891 break; 892 } 893 894 mutex_lock(&ubi->device_mutex); 895 err = ubi_remove_volume(desc, 0); 896 mutex_unlock(&ubi->device_mutex); 897 898 /* 899 * The volume is deleted (unless an error occurred), and the 900 * 'struct ubi_volume' object will be freed when 901 * 'ubi_close_volume()' will call 'put_device()'. 902 */ 903 ubi_close_volume(desc); 904 break; 905 } 906 907 /* Re-size volume command */ 908 case UBI_IOCRSVOL: 909 { 910 int pebs; 911 struct ubi_rsvol_req req; 912 913 dbg_gen("re-size volume"); 914 err = copy_from_user(&req, argp, sizeof(struct ubi_rsvol_req)); 915 if (err) { 916 err = -EFAULT; 917 break; 918 } 919 920 err = verify_rsvol_req(ubi, &req); 921 if (err) 922 break; 923 924 desc = ubi_open_volume(ubi->ubi_num, req.vol_id, UBI_EXCLUSIVE); 925 if (IS_ERR(desc)) { 926 err = PTR_ERR(desc); 927 break; 928 } 929 930 pebs = div_u64(req.bytes + desc->vol->usable_leb_size - 1, 931 desc->vol->usable_leb_size); 932 933 mutex_lock(&ubi->device_mutex); 934 err = ubi_resize_volume(desc, pebs); 935 mutex_unlock(&ubi->device_mutex); 936 ubi_close_volume(desc); 937 break; 938 } 939 940 /* Re-name volumes command */ 941 case UBI_IOCRNVOL: 942 { 943 struct ubi_rnvol_req *req; 944 945 dbg_gen("re-name volumes"); 946 req = kmalloc(sizeof(struct ubi_rnvol_req), GFP_KERNEL); 947 if (!req) { 948 err = -ENOMEM; 949 break; 950 } 951 952 err = copy_from_user(req, argp, sizeof(struct ubi_rnvol_req)); 953 if (err) { 954 err = -EFAULT; 955 kfree(req); 956 break; 957 } 958 959 err = rename_volumes(ubi, req); 960 kfree(req); 961 break; 962 } 963 964 /* Check a specific PEB for bitflips and scrub it if needed */ 965 case UBI_IOCRPEB: 966 { 967 int pnum; 968 969 err = get_user(pnum, (__user int32_t *)argp); 970 if (err) { 971 err = -EFAULT; 972 break; 973 } 974 975 err = ubi_bitflip_check(ubi, pnum, 0); 976 break; 977 } 978 979 /* Force scrubbing for a specific PEB */ 980 case UBI_IOCSPEB: 981 { 982 int pnum; 983 984 err = get_user(pnum, (__user int32_t *)argp); 985 if (err) { 986 err = -EFAULT; 987 break; 988 } 989 990 err = ubi_bitflip_check(ubi, pnum, 1); 991 break; 992 } 993 994 default: 995 err = -ENOTTY; 996 break; 997 } 998 999 ubi_put_device(ubi); 1000 return err; 1001 } 1002 1003 static long ctrl_cdev_ioctl(struct file *file, unsigned int cmd, 1004 unsigned long arg) 1005 { 1006 int err = 0; 1007 void __user *argp = (void __user *)arg; 1008 1009 if (!capable(CAP_SYS_RESOURCE)) 1010 return -EPERM; 1011 1012 switch (cmd) { 1013 /* Attach an MTD device command */ 1014 case UBI_IOCATT: 1015 { 1016 struct ubi_attach_req req; 1017 struct mtd_info *mtd; 1018 1019 dbg_gen("attach MTD device"); 1020 err = copy_from_user(&req, argp, sizeof(struct ubi_attach_req)); 1021 if (err) { 1022 err = -EFAULT; 1023 break; 1024 } 1025 1026 if (req.mtd_num < 0 || 1027 (req.ubi_num < 0 && req.ubi_num != UBI_DEV_NUM_AUTO)) { 1028 err = -EINVAL; 1029 break; 1030 } 1031 1032 mtd = get_mtd_device(NULL, req.mtd_num); 1033 if (IS_ERR(mtd)) { 1034 err = PTR_ERR(mtd); 1035 break; 1036 } 1037 1038 /* 1039 * Note, further request verification is done by 1040 * 'ubi_attach_mtd_dev()'. 1041 */ 1042 mutex_lock(&ubi_devices_mutex); 1043 err = ubi_attach_mtd_dev(mtd, req.ubi_num, req.vid_hdr_offset, 1044 req.max_beb_per1024, !!req.disable_fm); 1045 mutex_unlock(&ubi_devices_mutex); 1046 if (err < 0) 1047 put_mtd_device(mtd); 1048 else 1049 /* @err contains UBI device number */ 1050 err = put_user(err, (__user int32_t *)argp); 1051 1052 break; 1053 } 1054 1055 /* Detach an MTD device command */ 1056 case UBI_IOCDET: 1057 { 1058 int ubi_num; 1059 1060 dbg_gen("detach MTD device"); 1061 err = get_user(ubi_num, (__user int32_t *)argp); 1062 if (err) { 1063 err = -EFAULT; 1064 break; 1065 } 1066 1067 mutex_lock(&ubi_devices_mutex); 1068 err = ubi_detach_mtd_dev(ubi_num, 0); 1069 mutex_unlock(&ubi_devices_mutex); 1070 break; 1071 } 1072 1073 default: 1074 err = -ENOTTY; 1075 break; 1076 } 1077 1078 return err; 1079 } 1080 1081 /* UBI volume character device operations */ 1082 const struct file_operations ubi_vol_cdev_operations = { 1083 .owner = THIS_MODULE, 1084 .open = vol_cdev_open, 1085 .release = vol_cdev_release, 1086 .llseek = vol_cdev_llseek, 1087 .read = vol_cdev_read, 1088 .write = vol_cdev_write, 1089 .fsync = vol_cdev_fsync, 1090 .unlocked_ioctl = vol_cdev_ioctl, 1091 .compat_ioctl = compat_ptr_ioctl, 1092 }; 1093 1094 /* UBI character device operations */ 1095 const struct file_operations ubi_cdev_operations = { 1096 .owner = THIS_MODULE, 1097 .llseek = no_llseek, 1098 .unlocked_ioctl = ubi_cdev_ioctl, 1099 .compat_ioctl = compat_ptr_ioctl, 1100 }; 1101 1102 /* UBI control character device operations */ 1103 const struct file_operations ubi_ctrl_cdev_operations = { 1104 .owner = THIS_MODULE, 1105 .unlocked_ioctl = ctrl_cdev_ioctl, 1106 .compat_ioctl = compat_ptr_ioctl, 1107 .llseek = no_llseek, 1108 }; 1109