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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright (c) International Business Machines Corp., 20064 *5 * Author: Artem Bityutskiy (Битюцкий Артём)6 */7 8/* This file mostly implements UBI kernel API functions */9 10#include <linux/module.h>11#include <linux/err.h>12#include <linux/slab.h>13#include <linux/namei.h>14#include <linux/fs.h>15#include <asm/div64.h>16#include "ubi.h"17 18/**19 * ubi_do_get_device_info - get information about UBI device.20 * @ubi: UBI device description object21 * @di: the information is stored here22 *23 * This function is the same as 'ubi_get_device_info()', but it assumes the UBI24 * device is locked and cannot disappear.25 */26void ubi_do_get_device_info(struct ubi_device *ubi, struct ubi_device_info *di)27{28 di->ubi_num = ubi->ubi_num;29 di->leb_size = ubi->leb_size;30 di->leb_start = ubi->leb_start;31 di->min_io_size = ubi->min_io_size;32 di->max_write_size = ubi->max_write_size;33 di->ro_mode = ubi->ro_mode;34 di->cdev = ubi->cdev.dev;35}36EXPORT_SYMBOL_GPL(ubi_do_get_device_info);37 38/**39 * ubi_get_device_info - get information about UBI device.40 * @ubi_num: UBI device number41 * @di: the information is stored here42 *43 * This function returns %0 in case of success, %-EINVAL if the UBI device44 * number is invalid, and %-ENODEV if there is no such UBI device.45 */46int ubi_get_device_info(int ubi_num, struct ubi_device_info *di)47{48 struct ubi_device *ubi;49 50 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)51 return -EINVAL;52 ubi = ubi_get_device(ubi_num);53 if (!ubi)54 return -ENODEV;55 ubi_do_get_device_info(ubi, di);56 ubi_put_device(ubi);57 return 0;58}59EXPORT_SYMBOL_GPL(ubi_get_device_info);60 61/**62 * ubi_do_get_volume_info - get information about UBI volume.63 * @ubi: UBI device description object64 * @vol: volume description object65 * @vi: the information is stored here66 */67void ubi_do_get_volume_info(struct ubi_device *ubi, struct ubi_volume *vol,68 struct ubi_volume_info *vi)69{70 vi->vol_id = vol->vol_id;71 vi->ubi_num = ubi->ubi_num;72 vi->size = vol->reserved_pebs;73 vi->used_bytes = vol->used_bytes;74 vi->vol_type = vol->vol_type;75 vi->corrupted = vol->corrupted;76 vi->upd_marker = vol->upd_marker;77 vi->alignment = vol->alignment;78 vi->usable_leb_size = vol->usable_leb_size;79 vi->name_len = vol->name_len;80 vi->name = vol->name;81 vi->cdev = vol->cdev.dev;82 vi->dev = &vol->dev;83}84 85/**86 * ubi_get_volume_info - get information about UBI volume.87 * @desc: volume descriptor88 * @vi: the information is stored here89 */90void ubi_get_volume_info(struct ubi_volume_desc *desc,91 struct ubi_volume_info *vi)92{93 ubi_do_get_volume_info(desc->vol->ubi, desc->vol, vi);94}95EXPORT_SYMBOL_GPL(ubi_get_volume_info);96 97/**98 * ubi_open_volume - open UBI volume.99 * @ubi_num: UBI device number100 * @vol_id: volume ID101 * @mode: open mode102 *103 * The @mode parameter specifies if the volume should be opened in read-only104 * mode, read-write mode, or exclusive mode. The exclusive mode guarantees that105 * nobody else will be able to open this volume. UBI allows to have many volume106 * readers and one writer at a time.107 *108 * If a static volume is being opened for the first time since boot, it will be109 * checked by this function, which means it will be fully read and the CRC110 * checksum of each logical eraseblock will be checked.111 *112 * This function returns volume descriptor in case of success and a negative113 * error code in case of failure.114 */115struct ubi_volume_desc *ubi_open_volume(int ubi_num, int vol_id, int mode)116{117 int err;118 struct ubi_volume_desc *desc;119 struct ubi_device *ubi;120 struct ubi_volume *vol;121 122 dbg_gen("open device %d, volume %d, mode %d", ubi_num, vol_id, mode);123 124 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)125 return ERR_PTR(-EINVAL);126 127 if (mode != UBI_READONLY && mode != UBI_READWRITE &&128 mode != UBI_EXCLUSIVE && mode != UBI_METAONLY)129 return ERR_PTR(-EINVAL);130 131 /*132 * First of all, we have to get the UBI device to prevent its removal.133 */134 ubi = ubi_get_device(ubi_num);135 if (!ubi)136 return ERR_PTR(-ENODEV);137 138 if (vol_id < 0 || vol_id >= ubi->vtbl_slots) {139 err = -EINVAL;140 goto out_put_ubi;141 }142 143 desc = kmalloc(sizeof(struct ubi_volume_desc), GFP_KERNEL);144 if (!desc) {145 err = -ENOMEM;146 goto out_put_ubi;147 }148 149 err = -ENODEV;150 if (!try_module_get(THIS_MODULE))151 goto out_free;152 153 spin_lock(&ubi->volumes_lock);154 vol = ubi->volumes[vol_id];155 if (!vol || vol->is_dead)156 goto out_unlock;157 158 err = -EBUSY;159 switch (mode) {160 case UBI_READONLY:161 if (vol->exclusive)162 goto out_unlock;163 vol->readers += 1;164 break;165 166 case UBI_READWRITE:167 if (vol->exclusive || vol->writers > 0)168 goto out_unlock;169 vol->writers += 1;170 break;171 172 case UBI_EXCLUSIVE:173 if (vol->exclusive || vol->writers || vol->readers ||174 vol->metaonly)175 goto out_unlock;176 vol->exclusive = 1;177 break;178 179 case UBI_METAONLY:180 if (vol->metaonly || vol->exclusive)181 goto out_unlock;182 vol->metaonly = 1;183 break;184 }185 get_device(&vol->dev);186 vol->ref_count += 1;187 spin_unlock(&ubi->volumes_lock);188 189 desc->vol = vol;190 desc->mode = mode;191 192 mutex_lock(&ubi->ckvol_mutex);193 if (!vol->checked && !vol->skip_check) {194 /* This is the first open - check the volume */195 err = ubi_check_volume(ubi, vol_id);196 if (err < 0) {197 mutex_unlock(&ubi->ckvol_mutex);198 ubi_close_volume(desc);199 return ERR_PTR(err);200 }201 if (err == 1) {202 ubi_warn(ubi, "volume %d on UBI device %d is corrupted",203 vol_id, ubi->ubi_num);204 vol->corrupted = 1;205 }206 vol->checked = 1;207 }208 mutex_unlock(&ubi->ckvol_mutex);209 210 return desc;211 212out_unlock:213 spin_unlock(&ubi->volumes_lock);214 module_put(THIS_MODULE);215out_free:216 kfree(desc);217out_put_ubi:218 ubi_err(ubi, "cannot open device %d, volume %d, error %d",219 ubi_num, vol_id, err);220 ubi_put_device(ubi);221 return ERR_PTR(err);222}223EXPORT_SYMBOL_GPL(ubi_open_volume);224 225/**226 * ubi_open_volume_nm - open UBI volume by name.227 * @ubi_num: UBI device number228 * @name: volume name229 * @mode: open mode230 *231 * This function is similar to 'ubi_open_volume()', but opens a volume by name.232 */233struct ubi_volume_desc *ubi_open_volume_nm(int ubi_num, const char *name,234 int mode)235{236 int i, vol_id = -1, len;237 struct ubi_device *ubi;238 struct ubi_volume_desc *ret;239 240 dbg_gen("open device %d, volume %s, mode %d", ubi_num, name, mode);241 242 if (!name)243 return ERR_PTR(-EINVAL);244 245 len = strnlen(name, UBI_VOL_NAME_MAX + 1);246 if (len > UBI_VOL_NAME_MAX)247 return ERR_PTR(-EINVAL);248 249 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)250 return ERR_PTR(-EINVAL);251 252 ubi = ubi_get_device(ubi_num);253 if (!ubi)254 return ERR_PTR(-ENODEV);255 256 spin_lock(&ubi->volumes_lock);257 /* Walk all volumes of this UBI device */258 for (i = 0; i < ubi->vtbl_slots; i++) {259 struct ubi_volume *vol = ubi->volumes[i];260 261 if (vol && len == vol->name_len && !strcmp(name, vol->name)) {262 vol_id = i;263 break;264 }265 }266 spin_unlock(&ubi->volumes_lock);267 268 if (vol_id >= 0)269 ret = ubi_open_volume(ubi_num, vol_id, mode);270 else271 ret = ERR_PTR(-ENODEV);272 273 /*274 * We should put the UBI device even in case of success, because275 * 'ubi_open_volume()' took a reference as well.276 */277 ubi_put_device(ubi);278 return ret;279}280EXPORT_SYMBOL_GPL(ubi_open_volume_nm);281 282/**283 * ubi_get_num_by_path - get UBI device and volume number from device path284 * @pathname: volume character device node path285 * @ubi_num: pointer to UBI device number to be set286 * @vol_id: pointer to UBI volume ID to be set287 *288 * Returns 0 on success and sets ubi_num and vol_id, returns error otherwise.289 */290int ubi_get_num_by_path(const char *pathname, int *ubi_num, int *vol_id)291{292 int error;293 struct path path;294 struct kstat stat;295 296 error = kern_path(pathname, LOOKUP_FOLLOW, &path);297 if (error)298 return error;299 300 error = vfs_getattr(&path, &stat, STATX_TYPE, AT_STATX_SYNC_AS_STAT);301 path_put(&path);302 if (error)303 return error;304 305 if (!S_ISCHR(stat.mode))306 return -EINVAL;307 308 *ubi_num = ubi_major2num(MAJOR(stat.rdev));309 *vol_id = MINOR(stat.rdev) - 1;310 311 if (*vol_id < 0 || *ubi_num < 0)312 return -ENODEV;313 314 return 0;315}316 317/**318 * ubi_open_volume_path - open UBI volume by its character device node path.319 * @pathname: volume character device node path320 * @mode: open mode321 *322 * This function is similar to 'ubi_open_volume()', but opens a volume the path323 * to its character device node.324 */325struct ubi_volume_desc *ubi_open_volume_path(const char *pathname, int mode)326{327 int error, ubi_num, vol_id;328 329 dbg_gen("open volume %s, mode %d", pathname, mode);330 331 if (!pathname || !*pathname)332 return ERR_PTR(-EINVAL);333 334 error = ubi_get_num_by_path(pathname, &ubi_num, &vol_id);335 if (error)336 return ERR_PTR(error);337 338 return ubi_open_volume(ubi_num, vol_id, mode);339}340EXPORT_SYMBOL_GPL(ubi_open_volume_path);341 342/**343 * ubi_close_volume - close UBI volume.344 * @desc: volume descriptor345 */346void ubi_close_volume(struct ubi_volume_desc *desc)347{348 struct ubi_volume *vol = desc->vol;349 struct ubi_device *ubi = vol->ubi;350 351 dbg_gen("close device %d, volume %d, mode %d",352 ubi->ubi_num, vol->vol_id, desc->mode);353 354 spin_lock(&ubi->volumes_lock);355 switch (desc->mode) {356 case UBI_READONLY:357 vol->readers -= 1;358 break;359 case UBI_READWRITE:360 vol->writers -= 1;361 break;362 case UBI_EXCLUSIVE:363 vol->exclusive = 0;364 break;365 case UBI_METAONLY:366 vol->metaonly = 0;367 break;368 }369 vol->ref_count -= 1;370 spin_unlock(&ubi->volumes_lock);371 372 kfree(desc);373 put_device(&vol->dev);374 ubi_put_device(ubi);375 module_put(THIS_MODULE);376}377EXPORT_SYMBOL_GPL(ubi_close_volume);378 379/**380 * leb_read_sanity_check - does sanity checks on read requests.381 * @desc: volume descriptor382 * @lnum: logical eraseblock number to read from383 * @offset: offset within the logical eraseblock to read from384 * @len: how many bytes to read385 *386 * This function is used by ubi_leb_read() and ubi_leb_read_sg()387 * to perform sanity checks.388 */389static int leb_read_sanity_check(struct ubi_volume_desc *desc, int lnum,390 int offset, int len)391{392 struct ubi_volume *vol = desc->vol;393 struct ubi_device *ubi = vol->ubi;394 int vol_id = vol->vol_id;395 396 if (vol_id < 0 || vol_id >= ubi->vtbl_slots || lnum < 0 ||397 lnum >= vol->used_ebs || offset < 0 || len < 0 ||398 offset + len > vol->usable_leb_size)399 return -EINVAL;400 401 if (vol->vol_type == UBI_STATIC_VOLUME) {402 if (vol->used_ebs == 0)403 /* Empty static UBI volume */404 return 0;405 if (lnum == vol->used_ebs - 1 &&406 offset + len > vol->last_eb_bytes)407 return -EINVAL;408 }409 410 if (vol->upd_marker)411 return -EBADF;412 413 return 0;414}415 416/**417 * ubi_leb_read - read data.418 * @desc: volume descriptor419 * @lnum: logical eraseblock number to read from420 * @buf: buffer where to store the read data421 * @offset: offset within the logical eraseblock to read from422 * @len: how many bytes to read423 * @check: whether UBI has to check the read data's CRC or not.424 *425 * This function reads data from offset @offset of logical eraseblock @lnum and426 * stores the data at @buf. When reading from static volumes, @check specifies427 * whether the data has to be checked or not. If yes, the whole logical428 * eraseblock will be read and its CRC checksum will be checked (i.e., the CRC429 * checksum is per-eraseblock). So checking may substantially slow down the430 * read speed. The @check argument is ignored for dynamic volumes.431 *432 * In case of success, this function returns zero. In case of failure, this433 * function returns a negative error code.434 *435 * %-EBADMSG error code is returned:436 * o for both static and dynamic volumes if MTD driver has detected a data437 * integrity problem (unrecoverable ECC checksum mismatch in case of NAND);438 * o for static volumes in case of data CRC mismatch.439 *440 * If the volume is damaged because of an interrupted update this function just441 * returns immediately with %-EBADF error code.442 */443int ubi_leb_read(struct ubi_volume_desc *desc, int lnum, char *buf, int offset,444 int len, int check)445{446 struct ubi_volume *vol = desc->vol;447 struct ubi_device *ubi = vol->ubi;448 int err, vol_id = vol->vol_id;449 450 dbg_gen("read %d bytes from LEB %d:%d:%d", len, vol_id, lnum, offset);451 452 err = leb_read_sanity_check(desc, lnum, offset, len);453 if (err < 0)454 return err;455 456 if (len == 0)457 return 0;458 459 err = ubi_eba_read_leb(ubi, vol, lnum, buf, offset, len, check);460 if (err && mtd_is_eccerr(err) && vol->vol_type == UBI_STATIC_VOLUME) {461 ubi_warn(ubi, "mark volume %d as corrupted", vol_id);462 vol->corrupted = 1;463 }464 465 return err;466}467EXPORT_SYMBOL_GPL(ubi_leb_read);468 469 470/**471 * ubi_leb_read_sg - read data into a scatter gather list.472 * @desc: volume descriptor473 * @lnum: logical eraseblock number to read from474 * @sgl: UBI scatter gather list to store the read data475 * @offset: offset within the logical eraseblock to read from476 * @len: how many bytes to read477 * @check: whether UBI has to check the read data's CRC or not.478 *479 * This function works exactly like ubi_leb_read_sg(). But instead of480 * storing the read data into a buffer it writes to an UBI scatter gather481 * list.482 */483int ubi_leb_read_sg(struct ubi_volume_desc *desc, int lnum, struct ubi_sgl *sgl,484 int offset, int len, int check)485{486 struct ubi_volume *vol = desc->vol;487 struct ubi_device *ubi = vol->ubi;488 int err, vol_id = vol->vol_id;489 490 dbg_gen("read %d bytes from LEB %d:%d:%d", len, vol_id, lnum, offset);491 492 err = leb_read_sanity_check(desc, lnum, offset, len);493 if (err < 0)494 return err;495 496 if (len == 0)497 return 0;498 499 err = ubi_eba_read_leb_sg(ubi, vol, sgl, lnum, offset, len, check);500 if (err && mtd_is_eccerr(err) && vol->vol_type == UBI_STATIC_VOLUME) {501 ubi_warn(ubi, "mark volume %d as corrupted", vol_id);502 vol->corrupted = 1;503 }504 505 return err;506}507EXPORT_SYMBOL_GPL(ubi_leb_read_sg);508 509/**510 * ubi_leb_write - write data.511 * @desc: volume descriptor512 * @lnum: logical eraseblock number to write to513 * @buf: data to write514 * @offset: offset within the logical eraseblock where to write515 * @len: how many bytes to write516 *517 * This function writes @len bytes of data from @buf to offset @offset of518 * logical eraseblock @lnum.519 *520 * This function takes care of physical eraseblock write failures. If write to521 * the physical eraseblock write operation fails, the logical eraseblock is522 * re-mapped to another physical eraseblock, the data is recovered, and the523 * write finishes. UBI has a pool of reserved physical eraseblocks for this.524 *525 * If all the data were successfully written, zero is returned. If an error526 * occurred and UBI has not been able to recover from it, this function returns527 * a negative error code. Note, in case of an error, it is possible that528 * something was still written to the flash media, but that may be some529 * garbage.530 *531 * If the volume is damaged because of an interrupted update this function just532 * returns immediately with %-EBADF code.533 */534int ubi_leb_write(struct ubi_volume_desc *desc, int lnum, const void *buf,535 int offset, int len)536{537 struct ubi_volume *vol = desc->vol;538 struct ubi_device *ubi = vol->ubi;539 int vol_id = vol->vol_id;540 541 dbg_gen("write %d bytes to LEB %d:%d:%d", len, vol_id, lnum, offset);542 543 if (vol_id < 0 || vol_id >= ubi->vtbl_slots)544 return -EINVAL;545 546 if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME)547 return -EROFS;548 549 if (!ubi_leb_valid(vol, lnum) || offset < 0 || len < 0 ||550 offset + len > vol->usable_leb_size ||551 offset & (ubi->min_io_size - 1) || len & (ubi->min_io_size - 1))552 return -EINVAL;553 554 if (vol->upd_marker)555 return -EBADF;556 557 if (len == 0)558 return 0;559 560 return ubi_eba_write_leb(ubi, vol, lnum, buf, offset, len);561}562EXPORT_SYMBOL_GPL(ubi_leb_write);563 564/*565 * ubi_leb_change - change logical eraseblock atomically.566 * @desc: volume descriptor567 * @lnum: logical eraseblock number to change568 * @buf: data to write569 * @len: how many bytes to write570 *571 * This function changes the contents of a logical eraseblock atomically. @buf572 * has to contain new logical eraseblock data, and @len - the length of the573 * data, which has to be aligned. The length may be shorter than the logical574 * eraseblock size, ant the logical eraseblock may be appended to more times575 * later on. This function guarantees that in case of an unclean reboot the old576 * contents is preserved. Returns zero in case of success and a negative error577 * code in case of failure.578 */579int ubi_leb_change(struct ubi_volume_desc *desc, int lnum, const void *buf,580 int len)581{582 struct ubi_volume *vol = desc->vol;583 struct ubi_device *ubi = vol->ubi;584 int vol_id = vol->vol_id;585 586 dbg_gen("atomically write %d bytes to LEB %d:%d", len, vol_id, lnum);587 588 if (vol_id < 0 || vol_id >= ubi->vtbl_slots)589 return -EINVAL;590 591 if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME)592 return -EROFS;593 594 if (!ubi_leb_valid(vol, lnum) || len < 0 ||595 len > vol->usable_leb_size || len & (ubi->min_io_size - 1))596 return -EINVAL;597 598 if (vol->upd_marker)599 return -EBADF;600 601 if (len == 0)602 return 0;603 604 return ubi_eba_atomic_leb_change(ubi, vol, lnum, buf, len);605}606EXPORT_SYMBOL_GPL(ubi_leb_change);607 608/**609 * ubi_leb_erase - erase logical eraseblock.610 * @desc: volume descriptor611 * @lnum: logical eraseblock number612 *613 * This function un-maps logical eraseblock @lnum and synchronously erases the614 * correspondent physical eraseblock. Returns zero in case of success and a615 * negative error code in case of failure.616 *617 * If the volume is damaged because of an interrupted update this function just618 * returns immediately with %-EBADF code.619 */620int ubi_leb_erase(struct ubi_volume_desc *desc, int lnum)621{622 struct ubi_volume *vol = desc->vol;623 struct ubi_device *ubi = vol->ubi;624 int err;625 626 dbg_gen("erase LEB %d:%d", vol->vol_id, lnum);627 628 if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME)629 return -EROFS;630 631 if (!ubi_leb_valid(vol, lnum))632 return -EINVAL;633 634 if (vol->upd_marker)635 return -EBADF;636 637 err = ubi_eba_unmap_leb(ubi, vol, lnum);638 if (err)639 return err;640 641 return ubi_wl_flush(ubi, vol->vol_id, lnum);642}643EXPORT_SYMBOL_GPL(ubi_leb_erase);644 645/**646 * ubi_leb_unmap - un-map logical eraseblock.647 * @desc: volume descriptor648 * @lnum: logical eraseblock number649 *650 * This function un-maps logical eraseblock @lnum and schedules the651 * corresponding physical eraseblock for erasure, so that it will eventually be652 * physically erased in background. This operation is much faster than the653 * erase operation.654 *655 * Unlike erase, the un-map operation does not guarantee that the logical656 * eraseblock will contain all 0xFF bytes when UBI is initialized again. For657 * example, if several logical eraseblocks are un-mapped, and an unclean reboot658 * happens after this, the logical eraseblocks will not necessarily be659 * un-mapped again when this MTD device is attached. They may actually be660 * mapped to the same physical eraseblocks again. So, this function has to be661 * used with care.662 *663 * In other words, when un-mapping a logical eraseblock, UBI does not store664 * any information about this on the flash media, it just marks the logical665 * eraseblock as "un-mapped" in RAM. If UBI is detached before the physical666 * eraseblock is physically erased, it will be mapped again to the same logical667 * eraseblock when the MTD device is attached again.668 *669 * The main and obvious use-case of this function is when the contents of a670 * logical eraseblock has to be re-written. Then it is much more efficient to671 * first un-map it, then write new data, rather than first erase it, then write672 * new data. Note, once new data has been written to the logical eraseblock,673 * UBI guarantees that the old contents has gone forever. In other words, if an674 * unclean reboot happens after the logical eraseblock has been un-mapped and675 * then written to, it will contain the last written data.676 *677 * This function returns zero in case of success and a negative error code in678 * case of failure. If the volume is damaged because of an interrupted update679 * this function just returns immediately with %-EBADF code.680 */681int ubi_leb_unmap(struct ubi_volume_desc *desc, int lnum)682{683 struct ubi_volume *vol = desc->vol;684 struct ubi_device *ubi = vol->ubi;685 686 dbg_gen("unmap LEB %d:%d", vol->vol_id, lnum);687 688 if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME)689 return -EROFS;690 691 if (!ubi_leb_valid(vol, lnum))692 return -EINVAL;693 694 if (vol->upd_marker)695 return -EBADF;696 697 return ubi_eba_unmap_leb(ubi, vol, lnum);698}699EXPORT_SYMBOL_GPL(ubi_leb_unmap);700 701/**702 * ubi_leb_map - map logical eraseblock to a physical eraseblock.703 * @desc: volume descriptor704 * @lnum: logical eraseblock number705 *706 * This function maps an un-mapped logical eraseblock @lnum to a physical707 * eraseblock. This means, that after a successful invocation of this708 * function the logical eraseblock @lnum will be empty (contain only %0xFF709 * bytes) and be mapped to a physical eraseblock, even if an unclean reboot710 * happens.711 *712 * This function returns zero in case of success, %-EBADF if the volume is713 * damaged because of an interrupted update, %-EBADMSG if the logical714 * eraseblock is already mapped, and other negative error codes in case of715 * other failures.716 */717int ubi_leb_map(struct ubi_volume_desc *desc, int lnum)718{719 struct ubi_volume *vol = desc->vol;720 struct ubi_device *ubi = vol->ubi;721 722 dbg_gen("map LEB %d:%d", vol->vol_id, lnum);723 724 if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME)725 return -EROFS;726 727 if (!ubi_leb_valid(vol, lnum))728 return -EINVAL;729 730 if (vol->upd_marker)731 return -EBADF;732 733 if (ubi_eba_is_mapped(vol, lnum))734 return -EBADMSG;735 736 return ubi_eba_write_leb(ubi, vol, lnum, NULL, 0, 0);737}738EXPORT_SYMBOL_GPL(ubi_leb_map);739 740/**741 * ubi_is_mapped - check if logical eraseblock is mapped.742 * @desc: volume descriptor743 * @lnum: logical eraseblock number744 *745 * This function checks if logical eraseblock @lnum is mapped to a physical746 * eraseblock. If a logical eraseblock is un-mapped, this does not necessarily747 * mean it will still be un-mapped after the UBI device is re-attached. The748 * logical eraseblock may become mapped to the physical eraseblock it was last749 * mapped to.750 *751 * This function returns %1 if the LEB is mapped, %0 if not, and a negative752 * error code in case of failure. If the volume is damaged because of an753 * interrupted update this function just returns immediately with %-EBADF error754 * code.755 */756int ubi_is_mapped(struct ubi_volume_desc *desc, int lnum)757{758 struct ubi_volume *vol = desc->vol;759 760 dbg_gen("test LEB %d:%d", vol->vol_id, lnum);761 762 if (!ubi_leb_valid(vol, lnum))763 return -EINVAL;764 765 if (vol->upd_marker)766 return -EBADF;767 768 return ubi_eba_is_mapped(vol, lnum);769}770EXPORT_SYMBOL_GPL(ubi_is_mapped);771 772/**773 * ubi_sync - synchronize UBI device buffers.774 * @ubi_num: UBI device to synchronize775 *776 * The underlying MTD device may cache data in hardware or in software. This777 * function ensures the caches are flushed. Returns zero in case of success and778 * a negative error code in case of failure.779 */780int ubi_sync(int ubi_num)781{782 struct ubi_device *ubi;783 784 ubi = ubi_get_device(ubi_num);785 if (!ubi)786 return -ENODEV;787 788 mtd_sync(ubi->mtd);789 ubi_put_device(ubi);790 return 0;791}792EXPORT_SYMBOL_GPL(ubi_sync);793 794/**795 * ubi_flush - flush UBI work queue.796 * @ubi_num: UBI device to flush work queue797 * @vol_id: volume id to flush for798 * @lnum: logical eraseblock number to flush for799 *800 * This function executes all pending works for a particular volume id / logical801 * eraseblock number pair. If either value is set to %UBI_ALL, then it acts as802 * a wildcard for all of the corresponding volume numbers or logical803 * eraseblock numbers. It returns zero in case of success and a negative error804 * code in case of failure.805 */806int ubi_flush(int ubi_num, int vol_id, int lnum)807{808 struct ubi_device *ubi;809 int err = 0;810 811 ubi = ubi_get_device(ubi_num);812 if (!ubi)813 return -ENODEV;814 815 err = ubi_wl_flush(ubi, vol_id, lnum);816 ubi_put_device(ubi);817 return err;818}819EXPORT_SYMBOL_GPL(ubi_flush);820 821BLOCKING_NOTIFIER_HEAD(ubi_notifiers);822 823/**824 * ubi_register_volume_notifier - register a volume notifier.825 * @nb: the notifier description object826 * @ignore_existing: if non-zero, do not send "added" notification for all827 * already existing volumes828 *829 * This function registers a volume notifier, which means that830 * 'nb->notifier_call()' will be invoked when an UBI volume is created,831 * removed, re-sized, re-named, or updated. The first argument of the function832 * is the notification type. The second argument is pointer to a833 * &struct ubi_notification object which describes the notification event.834 * Using UBI API from the volume notifier is prohibited.835 *836 * This function returns zero in case of success and a negative error code837 * in case of failure.838 */839int ubi_register_volume_notifier(struct notifier_block *nb,840 int ignore_existing)841{842 int err;843 844 err = blocking_notifier_chain_register(&ubi_notifiers, nb);845 if (err != 0)846 return err;847 if (ignore_existing)848 return 0;849 850 /*851 * We are going to walk all UBI devices and all volumes, and852 * notify the user about existing volumes by the %UBI_VOLUME_ADDED853 * event. We have to lock the @ubi_devices_mutex to make sure UBI854 * devices do not disappear.855 */856 mutex_lock(&ubi_devices_mutex);857 ubi_enumerate_volumes(nb);858 mutex_unlock(&ubi_devices_mutex);859 860 return err;861}862EXPORT_SYMBOL_GPL(ubi_register_volume_notifier);863 864/**865 * ubi_unregister_volume_notifier - unregister the volume notifier.866 * @nb: the notifier description object867 *868 * This function unregisters volume notifier @nm and returns zero in case of869 * success and a negative error code in case of failure.870 */871int ubi_unregister_volume_notifier(struct notifier_block *nb)872{873 return blocking_notifier_chain_unregister(&ubi_notifiers, nb);874}875EXPORT_SYMBOL_GPL(ubi_unregister_volume_notifier);876