UBI (Latin: "where?") stands for "Unsorted Block Images". It is a volume management system for flash devices which manages multiple logical volumes on a single physical flash device and spreads the I/O load (i.e, wear-leveling) across the whole flash chip.

In a sense, UBI may be compared to the Logical Volume Manager (LVM). Whereas LVM maps logical sectors to physical sectors, UBI maps logical eraseblocks to physical eraseblocks. But besides the mapping, UBI implements global wear-leveling and I/O errors handling.

For more details, Please visit the following URL. http://www.linux-mtd.infradead.org/doc/ubi.html

Signed-off-by: Kyungmin Park kyungmin.park@samsung.com --- diff --git a/drivers/mtd/ubi/kapi.c b/drivers/mtd/ubi/kapi.c new file mode 100644 index 0000000..423d479 --- /dev/null +++ b/drivers/mtd/ubi/kapi.c @@ -0,0 +1,638 @@ +/* + * Copyright (c) International Business Machines Corp., 2006 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See + * the GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + * Author: Artem Bityutskiy (Битюцкий Артём) + */ + +/* This file mostly implements UBI kernel API functions */ + +#ifdef UBI_LINUX +#include <linux/module.h> +#include <linux/err.h> +#include <asm/div64.h> +#endif + +#include <ubi_uboot.h> +#include "ubi.h" + +/** + * ubi_get_device_info - get information about UBI device. + * @ubi_num: UBI device number + * @di: the information is stored here + * + * This function returns %0 in case of success, %-EINVAL if the UBI device + * number is invalid, and %-ENODEV if there is no such UBI device. + */ +int ubi_get_device_info(int ubi_num, struct ubi_device_info *di) +{ + struct ubi_device *ubi; + + if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES) + return -EINVAL; + + ubi = ubi_get_device(ubi_num); + if (!ubi) + return -ENODEV; + + di->ubi_num = ubi->ubi_num; + di->leb_size = ubi->leb_size; + di->min_io_size = ubi->min_io_size; + di->ro_mode = ubi->ro_mode; + di->cdev = ubi->cdev.dev; + + ubi_put_device(ubi); + return 0; +} +EXPORT_SYMBOL_GPL(ubi_get_device_info); + +/** + * ubi_get_volume_info - get information about UBI volume. + * @desc: volume descriptor + * @vi: the information is stored here + */ +void ubi_get_volume_info(struct ubi_volume_desc *desc, + struct ubi_volume_info *vi) +{ + const struct ubi_volume *vol = desc->vol; + const struct ubi_device *ubi = vol->ubi; + + vi->vol_id = vol->vol_id; + vi->ubi_num = ubi->ubi_num; + vi->size = vol->reserved_pebs; + vi->used_bytes = vol->used_bytes; + vi->vol_type = vol->vol_type; + vi->corrupted = vol->corrupted; + vi->upd_marker = vol->upd_marker; + vi->alignment = vol->alignment; + vi->usable_leb_size = vol->usable_leb_size; + vi->name_len = vol->name_len; + vi->name = vol->name; + vi->cdev = vol->cdev.dev; +} +EXPORT_SYMBOL_GPL(ubi_get_volume_info); + +/** + * ubi_open_volume - open UBI volume. + * @ubi_num: UBI device number + * @vol_id: volume ID + * @mode: open mode + * + * The @mode parameter specifies if the volume should be opened in read-only + * mode, read-write mode, or exclusive mode. The exclusive mode guarantees that + * nobody else will be able to open this volume. UBI allows to have many volume + * readers and one writer at a time. + * + * If a static volume is being opened for the first time since boot, it will be + * checked by this function, which means it will be fully read and the CRC + * checksum of each logical eraseblock will be checked. + * + * This function returns volume descriptor in case of success and a negative + * error code in case of failure. + */ +struct ubi_volume_desc *ubi_open_volume(int ubi_num, int vol_id, int mode) +{ + int err; + struct ubi_volume_desc *desc; + struct ubi_device *ubi; + struct ubi_volume *vol; + + dbg_msg("open device %d volume %d, mode %d", ubi_num, vol_id, mode); + + if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES) + return ERR_PTR(-EINVAL); + + if (mode != UBI_READONLY && mode != UBI_READWRITE && + mode != UBI_EXCLUSIVE) + return ERR_PTR(-EINVAL); + + /* + * First of all, we have to get the UBI device to prevent its removal. + */ + ubi = ubi_get_device(ubi_num); + if (!ubi) + return ERR_PTR(-ENODEV); + + if (vol_id < 0 || vol_id >= ubi->vtbl_slots) { + err = -EINVAL; + goto out_put_ubi; + } + + desc = kmalloc(sizeof(struct ubi_volume_desc), GFP_KERNEL); + if (!desc) { + err = -ENOMEM; + goto out_put_ubi; + } + + err = -ENODEV; + if (!try_module_get(THIS_MODULE)) + goto out_free; + + spin_lock(&ubi->volumes_lock); + vol = ubi->volumes[vol_id]; + if (!vol) + goto out_unlock; + + err = -EBUSY; + switch (mode) { + case UBI_READONLY: + if (vol->exclusive) + goto out_unlock; + vol->readers += 1; + break; + + case UBI_READWRITE: + if (vol->exclusive || vol->writers > 0) + goto out_unlock; + vol->writers += 1; + break; + + case UBI_EXCLUSIVE: + if (vol->exclusive || vol->writers || vol->readers) + goto out_unlock; + vol->exclusive = 1; + break; + } + get_device(&vol->dev); + vol->ref_count += 1; + spin_unlock(&ubi->volumes_lock); + + desc->vol = vol; + desc->mode = mode; + + mutex_lock(&ubi->ckvol_mutex); + if (!vol->checked) { + /* This is the first open - check the volume */ + err = ubi_check_volume(ubi, vol_id); + if (err < 0) { + mutex_unlock(&ubi->ckvol_mutex); + ubi_close_volume(desc); + return ERR_PTR(err); + } + if (err == 1) { + ubi_warn("volume %d on UBI device %d is corrupted", + vol_id, ubi->ubi_num); + vol->corrupted = 1; + } + vol->checked = 1; + } + mutex_unlock(&ubi->ckvol_mutex); + + return desc; + +out_unlock: + spin_unlock(&ubi->volumes_lock); + module_put(THIS_MODULE); +out_free: + kfree(desc); +out_put_ubi: + ubi_put_device(ubi); + return ERR_PTR(err); +} +EXPORT_SYMBOL_GPL(ubi_open_volume); + +/** + * ubi_open_volume_nm - open UBI volume by name. + * @ubi_num: UBI device number + * @name: volume name + * @mode: open mode + * + * This function is similar to 'ubi_open_volume()', but opens a volume by name. + */ +struct ubi_volume_desc *ubi_open_volume_nm(int ubi_num, const char *name, + int mode) +{ + int i, vol_id = -1, len; + struct ubi_device *ubi; + struct ubi_volume_desc *ret; + + dbg_msg("open volume %s, mode %d", name, mode); + + if (!name) + return ERR_PTR(-EINVAL); + + len = strnlen(name, UBI_VOL_NAME_MAX + 1); + if (len > UBI_VOL_NAME_MAX) + return ERR_PTR(-EINVAL); + + if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES) + return ERR_PTR(-EINVAL); + + ubi = ubi_get_device(ubi_num); + if (!ubi) + return ERR_PTR(-ENODEV); + + spin_lock(&ubi->volumes_lock); + /* Walk all volumes of this UBI device */ + for (i = 0; i < ubi->vtbl_slots; i++) { + struct ubi_volume *vol = ubi->volumes[i]; + + if (vol && len == vol->name_len && !strcmp(name, vol->name)) { + vol_id = i; + break; + } + } + spin_unlock(&ubi->volumes_lock); + + if (vol_id >= 0) + ret = ubi_open_volume(ubi_num, vol_id, mode); + else + ret = ERR_PTR(-ENODEV); + + /* + * We should put the UBI device even in case of success, because + * 'ubi_open_volume()' took a reference as well. + */ + ubi_put_device(ubi); + return ret; +} +EXPORT_SYMBOL_GPL(ubi_open_volume_nm); + +/** + * ubi_close_volume - close UBI volume. + * @desc: volume descriptor + */ +void ubi_close_volume(struct ubi_volume_desc *desc) +{ + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + + dbg_msg("close volume %d, mode %d", vol->vol_id, desc->mode); + + spin_lock(&ubi->volumes_lock); + switch (desc->mode) { + case UBI_READONLY: + vol->readers -= 1; + break; + case UBI_READWRITE: + vol->writers -= 1; + break; + case UBI_EXCLUSIVE: + vol->exclusive = 0; + } + vol->ref_count -= 1; + spin_unlock(&ubi->volumes_lock); + + kfree(desc); + put_device(&vol->dev); + ubi_put_device(ubi); + module_put(THIS_MODULE); +} +EXPORT_SYMBOL_GPL(ubi_close_volume); + +/** + * ubi_leb_read - read data. + * @desc: volume descriptor + * @lnum: logical eraseblock number to read from + * @buf: buffer where to store the read data + * @offset: offset within the logical eraseblock to read from + * @len: how many bytes to read + * @check: whether UBI has to check the read data's CRC or not. + * + * This function reads data from offset @offset of logical eraseblock @lnum and + * stores the data at @buf. When reading from static volumes, @check specifies + * whether the data has to be checked or not. If yes, the whole logical + * eraseblock will be read and its CRC checksum will be checked (i.e., the CRC + * checksum is per-eraseblock). So checking may substantially slow down the + * read speed. The @check argument is ignored for dynamic volumes. + * + * In case of success, this function returns zero. In case of failure, this + * function returns a negative error code. + * + * %-EBADMSG error code is returned: + * o for both static and dynamic volumes if MTD driver has detected a data + * integrity problem (unrecoverable ECC checksum mismatch in case of NAND); + * o for static volumes in case of data CRC mismatch. + * + * If the volume is damaged because of an interrupted update this function just + * returns immediately with %-EBADF error code. + */ +int ubi_leb_read(struct ubi_volume_desc *desc, int lnum, char *buf, int offset, + int len, int check) +{ + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + int err, vol_id = vol->vol_id; + + dbg_msg("read %d bytes from LEB %d:%d:%d", len, vol_id, lnum, offset); + + if (vol_id < 0 || vol_id >= ubi->vtbl_slots || lnum < 0 || + lnum >= vol->used_ebs || offset < 0 || len < 0 || + offset + len > vol->usable_leb_size) + return -EINVAL; + + if (vol->vol_type == UBI_STATIC_VOLUME) { + if (vol->used_ebs == 0) + /* Empty static UBI volume */ + return 0; + if (lnum == vol->used_ebs - 1 && + offset + len > vol->last_eb_bytes) + return -EINVAL; + } + + if (vol->upd_marker) + return -EBADF; + if (len == 0) + return 0; + + err = ubi_eba_read_leb(ubi, vol, lnum, buf, offset, len, check); + if (err && err == -EBADMSG && vol->vol_type == UBI_STATIC_VOLUME) { + ubi_warn("mark volume %d as corrupted", vol_id); + vol->corrupted = 1; + } + + return err; +} +EXPORT_SYMBOL_GPL(ubi_leb_read); + +/** + * ubi_leb_write - write data. + * @desc: volume descriptor + * @lnum: logical eraseblock number to write to + * @buf: data to write + * @offset: offset within the logical eraseblock where to write + * @len: how many bytes to write + * @dtype: expected data type + * + * This function writes @len bytes of data from @buf to offset @offset of + * logical eraseblock @lnum. The @dtype argument describes expected lifetime of + * the data. + * + * This function takes care of physical eraseblock write failures. If write to + * the physical eraseblock write operation fails, the logical eraseblock is + * re-mapped to another physical eraseblock, the data is recovered, and the + * write finishes. UBI has a pool of reserved physical eraseblocks for this. + * + * If all the data were successfully written, zero is returned. If an error + * occurred and UBI has not been able to recover from it, this function returns + * a negative error code. Note, in case of an error, it is possible that + * something was still written to the flash media, but that may be some + * garbage. + * + * If the volume is damaged because of an interrupted update this function just + * returns immediately with %-EBADF code. + */ +int ubi_leb_write(struct ubi_volume_desc *desc, int lnum, const void *buf, + int offset, int len, int dtype) +{ + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + int vol_id = vol->vol_id; + + dbg_msg("write %d bytes to LEB %d:%d:%d", len, vol_id, lnum, offset); + + if (vol_id < 0 || vol_id >= ubi->vtbl_slots) + return -EINVAL; + + if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME) + return -EROFS; + + if (lnum < 0 || lnum >= vol->reserved_pebs || offset < 0 || len < 0 || + offset + len > vol->usable_leb_size || + offset & (ubi->min_io_size - 1) || len & (ubi->min_io_size - 1)) + return -EINVAL; + + if (dtype != UBI_LONGTERM && dtype != UBI_SHORTTERM && + dtype != UBI_UNKNOWN) + return -EINVAL; + + if (vol->upd_marker) + return -EBADF; + + if (len == 0) + return 0; + + return ubi_eba_write_leb(ubi, vol, lnum, buf, offset, len, dtype); +} +EXPORT_SYMBOL_GPL(ubi_leb_write); + +/* + * ubi_leb_change - change logical eraseblock atomically. + * @desc: volume descriptor + * @lnum: logical eraseblock number to change + * @buf: data to write + * @len: how many bytes to write + * @dtype: expected data type + * + * This function changes the contents of a logical eraseblock atomically. @buf + * has to contain new logical eraseblock data, and @len - the length of the + * data, which has to be aligned. The length may be shorter then the logical + * eraseblock size, ant the logical eraseblock may be appended to more times + * later on. This function guarantees that in case of an unclean reboot the old + * contents is preserved. Returns zero in case of success and a negative error + * code in case of failure. + */ +int ubi_leb_change(struct ubi_volume_desc *desc, int lnum, const void *buf, + int len, int dtype) +{ + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + int vol_id = vol->vol_id; + + dbg_msg("atomically write %d bytes to LEB %d:%d", len, vol_id, lnum); + + if (vol_id < 0 || vol_id >= ubi->vtbl_slots) + return -EINVAL; + + if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME) + return -EROFS; + + if (lnum < 0 || lnum >= vol->reserved_pebs || len < 0 || + len > vol->usable_leb_size || len & (ubi->min_io_size - 1)) + return -EINVAL; + + if (dtype != UBI_LONGTERM && dtype != UBI_SHORTTERM && + dtype != UBI_UNKNOWN) + return -EINVAL; + + if (vol->upd_marker) + return -EBADF; + + if (len == 0) + return 0; + + return ubi_eba_atomic_leb_change(ubi, vol, lnum, buf, len, dtype); +} +EXPORT_SYMBOL_GPL(ubi_leb_change); + +/** + * ubi_leb_erase - erase logical eraseblock. + * @desc: volume descriptor + * @lnum: logical eraseblock number + * + * This function un-maps logical eraseblock @lnum and synchronously erases the + * correspondent physical eraseblock. Returns zero in case of success and a + * negative error code in case of failure. + * + * If the volume is damaged because of an interrupted update this function just + * returns immediately with %-EBADF code. + */ +int ubi_leb_erase(struct ubi_volume_desc *desc, int lnum) +{ + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + int err; + + dbg_msg("erase LEB %d:%d", vol->vol_id, lnum); + + if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME) + return -EROFS; + + if (lnum < 0 || lnum >= vol->reserved_pebs) + return -EINVAL; + + if (vol->upd_marker) + return -EBADF; + + err = ubi_eba_unmap_leb(ubi, vol, lnum); + if (err) + return err; + + return ubi_wl_flush(ubi); +} +EXPORT_SYMBOL_GPL(ubi_leb_erase); + +/** + * ubi_leb_unmap - un-map logical eraseblock. + * @desc: volume descriptor + * @lnum: logical eraseblock number + * + * This function un-maps logical eraseblock @lnum and schedules the + * corresponding physical eraseblock for erasure, so that it will eventually be + * physically erased in background. This operation is much faster then the + * erase operation. + * + * Unlike erase, the un-map operation does not guarantee that the logical + * eraseblock will contain all 0xFF bytes when UBI is initialized again. For + * example, if several logical eraseblocks are un-mapped, and an unclean reboot + * happens after this, the logical eraseblocks will not necessarily be + * un-mapped again when this MTD device is attached. They may actually be + * mapped to the same physical eraseblocks again. So, this function has to be + * used with care. + * + * In other words, when un-mapping a logical eraseblock, UBI does not store + * any information about this on the flash media, it just marks the logical + * eraseblock as "un-mapped" in RAM. If UBI is detached before the physical + * eraseblock is physically erased, it will be mapped again to the same logical + * eraseblock when the MTD device is attached again. + * + * The main and obvious use-case of this function is when the contents of a + * logical eraseblock has to be re-written. Then it is much more efficient to + * first un-map it, then write new data, rather then first erase it, then write + * new data. Note, once new data has been written to the logical eraseblock, + * UBI guarantees that the old contents has gone forever. In other words, if an + * unclean reboot happens after the logical eraseblock has been un-mapped and + * then written to, it will contain the last written data. + * + * This function returns zero in case of success and a negative error code in + * case of failure. If the volume is damaged because of an interrupted update + * this function just returns immediately with %-EBADF code. + */ +int ubi_leb_unmap(struct ubi_volume_desc *desc, int lnum) +{ + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + + dbg_msg("unmap LEB %d:%d", vol->vol_id, lnum); + + if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME) + return -EROFS; + + if (lnum < 0 || lnum >= vol->reserved_pebs) + return -EINVAL; + + if (vol->upd_marker) + return -EBADF; + + return ubi_eba_unmap_leb(ubi, vol, lnum); +} +EXPORT_SYMBOL_GPL(ubi_leb_unmap); + +/** + * ubi_leb_map - map logical erasblock to a physical eraseblock. + * @desc: volume descriptor + * @lnum: logical eraseblock number + * @dtype: expected data type + * + * This function maps an un-mapped logical eraseblock @lnum to a physical + * eraseblock. This means, that after a successfull invocation of this + * function the logical eraseblock @lnum will be empty (contain only %0xFF + * bytes) and be mapped to a physical eraseblock, even if an unclean reboot + * happens. + * + * This function returns zero in case of success, %-EBADF if the volume is + * damaged because of an interrupted update, %-EBADMSG if the logical + * eraseblock is already mapped, and other negative error codes in case of + * other failures. + */ +int ubi_leb_map(struct ubi_volume_desc *desc, int lnum, int dtype) +{ + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + + dbg_msg("unmap LEB %d:%d", vol->vol_id, lnum); + + if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME) + return -EROFS; + + if (lnum < 0 || lnum >= vol->reserved_pebs) + return -EINVAL; + + if (dtype != UBI_LONGTERM && dtype != UBI_SHORTTERM && + dtype != UBI_UNKNOWN) + return -EINVAL; + + if (vol->upd_marker) + return -EBADF; + + if (vol->eba_tbl[lnum] >= 0) + return -EBADMSG; + + return ubi_eba_write_leb(ubi, vol, lnum, NULL, 0, 0, dtype); +} +EXPORT_SYMBOL_GPL(ubi_leb_map); + +/** + * ubi_is_mapped - check if logical eraseblock is mapped. + * @desc: volume descriptor + * @lnum: logical eraseblock number + * + * This function checks if logical eraseblock @lnum is mapped to a physical + * eraseblock. If a logical eraseblock is un-mapped, this does not necessarily + * mean it will still be un-mapped after the UBI device is re-attached. The + * logical eraseblock may become mapped to the physical eraseblock it was last + * mapped to. + * + * This function returns %1 if the LEB is mapped, %0 if not, and a negative + * error code in case of failure. If the volume is damaged because of an + * interrupted update this function just returns immediately with %-EBADF error + * code. + */ +int ubi_is_mapped(struct ubi_volume_desc *desc, int lnum) +{ + struct ubi_volume *vol = desc->vol; + + dbg_msg("test LEB %d:%d", vol->vol_id, lnum); + + if (lnum < 0 || lnum >= vol->reserved_pebs) + return -EINVAL; + + if (vol->upd_marker) + return -EBADF; + + return vol->eba_tbl[lnum] >= 0; +} +EXPORT_SYMBOL_GPL(ubi_is_mapped); diff --git a/drivers/mtd/ubi/upd.c b/drivers/mtd/ubi/upd.c new file mode 100644 index 0000000..5f7ed7b --- /dev/null +++ b/drivers/mtd/ubi/upd.c @@ -0,0 +1,441 @@ +/* + * Copyright (c) International Business Machines Corp., 2006 + * Copyright (c) Nokia Corporation, 2006 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See + * the GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + * Author: Artem Bityutskiy (Битюцкий Артём) + * + * Jan 2007: Alexander Schmidt, hacked per-volume update. + */ + +/* + * This file contains implementation of the volume update and atomic LEB change + * functionality. + * + * The update operation is based on the per-volume update marker which is + * stored in the volume table. The update marker is set before the update + * starts, and removed after the update has been finished. So if the update was + * interrupted by an unclean re-boot or due to some other reasons, the update + * marker stays on the flash media and UBI finds it when it attaches the MTD + * device next time. If the update marker is set for a volume, the volume is + * treated as damaged and most I/O operations are prohibited. Only a new update + * operation is allowed. + * + * Note, in general it is possible to implement the update operation as a + * transaction with a roll-back capability. + */ + +#ifdef UBI_LINUX +#include <linux/err.h> +#include <asm/uaccess.h> +#include <asm/div64.h> +#endif + +#include <ubi_uboot.h> +#include "ubi.h" + +/** + * set_update_marker - set update marker. + * @ubi: UBI device description object + * @vol: volume description object + * + * This function sets the update marker flag for volume @vol. Returns zero + * in case of success and a negative error code in case of failure. + */ +static int set_update_marker(struct ubi_device *ubi, struct ubi_volume *vol) +{ + int err; + struct ubi_vtbl_record vtbl_rec; + + dbg_msg("set update marker for volume %d", vol->vol_id); + + if (vol->upd_marker) { + ubi_assert(ubi->vtbl[vol->vol_id].upd_marker); + dbg_msg("already set"); + return 0; + } + + memcpy(&vtbl_rec, &ubi->vtbl[vol->vol_id], + sizeof(struct ubi_vtbl_record)); + vtbl_rec.upd_marker = 1; + + mutex_lock(&ubi->volumes_mutex); + err = ubi_change_vtbl_record(ubi, vol->vol_id, &vtbl_rec); + mutex_unlock(&ubi->volumes_mutex); + vol->upd_marker = 1; + return err; +} + +/** + * clear_update_marker - clear update marker. + * @ubi: UBI device description object + * @vol: volume description object + * @bytes: new data size in bytes + * + * This function clears the update marker for volume @vol, sets new volume + * data size and clears the "corrupted" flag (static volumes only). Returns + * zero in case of success and a negative error code in case of failure. + */ +static int clear_update_marker(struct ubi_device *ubi, struct ubi_volume *vol, + long long bytes) +{ + int err; + uint64_t tmp; + struct ubi_vtbl_record vtbl_rec; + + dbg_msg("clear update marker for volume %d", vol->vol_id); + + memcpy(&vtbl_rec, &ubi->vtbl[vol->vol_id], + sizeof(struct ubi_vtbl_record)); + ubi_assert(vol->upd_marker && vtbl_rec.upd_marker); + vtbl_rec.upd_marker = 0; + + if (vol->vol_type == UBI_STATIC_VOLUME) { + vol->corrupted = 0; + vol->used_bytes = tmp = bytes; + vol->last_eb_bytes = do_div(tmp, vol->usable_leb_size); + vol->used_ebs = tmp; + if (vol->last_eb_bytes) + vol->used_ebs += 1; + else + vol->last_eb_bytes = vol->usable_leb_size; + } + + mutex_lock(&ubi->volumes_mutex); + err = ubi_change_vtbl_record(ubi, vol->vol_id, &vtbl_rec); + mutex_unlock(&ubi->volumes_mutex); + vol->upd_marker = 0; + return err; +} + +/** + * ubi_start_update - start volume update. + * @ubi: UBI device description object + * @vol: volume description object + * @bytes: update bytes + * + * This function starts volume update operation. If @bytes is zero, the volume + * is just wiped out. Returns zero in case of success and a negative error code + * in case of failure. + */ +int ubi_start_update(struct ubi_device *ubi, struct ubi_volume *vol, + long long bytes) +{ + int i, err; + uint64_t tmp; + + dbg_msg("start update of volume %d, %llu bytes", vol->vol_id, bytes); + ubi_assert(!vol->updating && !vol->changing_leb); + vol->updating = 1; + + err = set_update_marker(ubi, vol); + if (err) + return err; + + /* Before updating - wipe out the volume */ + for (i = 0; i < vol->reserved_pebs; i++) { + err = ubi_eba_unmap_leb(ubi, vol, i); + if (err) + return err; + } + + if (bytes == 0) { + err = clear_update_marker(ubi, vol, 0); + if (err) + return err; + err = ubi_wl_flush(ubi); + if (!err) + vol->updating = 0; + } + + vol->upd_buf = vmalloc(ubi->leb_size); + if (!vol->upd_buf) + return -ENOMEM; + + tmp = bytes; + vol->upd_ebs = !!do_div(tmp, vol->usable_leb_size); + vol->upd_ebs += tmp; + vol->upd_bytes = bytes; + vol->upd_received = 0; + return 0; +} + +/** + * ubi_start_leb_change - start atomic LEB change. + * @ubi: UBI device description object + * @vol: volume description object + * @req: operation request + * + * This function starts atomic LEB change operation. Returns zero in case of + * success and a negative error code in case of failure. + */ +int ubi_start_leb_change(struct ubi_device *ubi, struct ubi_volume *vol, + const struct ubi_leb_change_req *req) +{ + ubi_assert(!vol->updating && !vol->changing_leb); + + dbg_msg("start changing LEB %d:%d, %u bytes", + vol->vol_id, req->lnum, req->bytes); + if (req->bytes == 0) + return ubi_eba_atomic_leb_change(ubi, vol, req->lnum, NULL, 0, + req->dtype); + + vol->upd_bytes = req->bytes; + vol->upd_received = 0; + vol->changing_leb = 1; + vol->ch_lnum = req->lnum; + vol->ch_dtype = req->dtype; + + vol->upd_buf = vmalloc(req->bytes); + if (!vol->upd_buf) + return -ENOMEM; + + return 0; +} + +/** + * write_leb - write update data. + * @ubi: UBI device description object + * @vol: volume description object + * @lnum: logical eraseblock number + * @buf: data to write + * @len: data size + * @used_ebs: how many logical eraseblocks will this volume contain (static + * volumes only) + * + * This function writes update data to corresponding logical eraseblock. In + * case of dynamic volume, this function checks if the data contains 0xFF bytes + * at the end. If yes, the 0xFF bytes are cut and not written. So if the whole + * buffer contains only 0xFF bytes, the LEB is left unmapped. + * + * The reason why we skip the trailing 0xFF bytes in case of dynamic volume is + * that we want to make sure that more data may be appended to the logical + * eraseblock in future. Indeed, writing 0xFF bytes may have side effects and + * this PEB won't be writable anymore. So if one writes the file-system image + * to the UBI volume where 0xFFs mean free space - UBI makes sure this free + * space is writable after the update. + * + * We do not do this for static volumes because they are read-only. But this + * also cannot be done because we have to store per-LEB CRC and the correct + * data length. + * + * This function returns zero in case of success and a negative error code in + * case of failure. + */ +static int write_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum, + void *buf, int len, int used_ebs) +{ + int err; + + if (vol->vol_type == UBI_DYNAMIC_VOLUME) { + int l = ALIGN(len, ubi->min_io_size); + + memset(buf + len, 0xFF, l - len); + len = ubi_calc_data_len(ubi, buf, l); + if (len == 0) { + dbg_msg("all %d bytes contain 0xFF - skip", len); + return 0; + } + + err = ubi_eba_write_leb(ubi, vol, lnum, buf, 0, len, UBI_UNKNOWN); + } else { + /* + * When writing static volume, and this is the last logical + * eraseblock, the length (@len) does not have to be aligned to + * the minimal flash I/O unit. The 'ubi_eba_write_leb_st()' + * function accepts exact (unaligned) length and stores it in + * the VID header. And it takes care of proper alignment by + * padding the buffer. Here we just make sure the padding will + * contain zeros, not random trash. + */ + memset(buf + len, 0, vol->usable_leb_size - len); + err = ubi_eba_write_leb_st(ubi, vol, lnum, buf, len, + UBI_UNKNOWN, used_ebs); + } + + return err; +} + +/** + * ubi_more_update_data - write more update data. + * @vol: volume description object + * @buf: write data (user-space memory buffer) + * @count: how much bytes to write + * + * This function writes more data to the volume which is being updated. It may + * be called arbitrary number of times until all the update data arriveis. This + * function returns %0 in case of success, number of bytes written during the + * last call if the whole volume update has been successfully finished, and a + * negative error code in case of failure. + */ +int ubi_more_update_data(struct ubi_device *ubi, struct ubi_volume *vol, + const void __user *buf, int count) +{ + uint64_t tmp; + int lnum, offs, err = 0, len, to_write = count; + + dbg_msg("write %d of %lld bytes, %lld already passed", + count, vol->upd_bytes, vol->upd_received); + + if (ubi->ro_mode) + return -EROFS; + + tmp = vol->upd_received; + offs = do_div(tmp, vol->usable_leb_size); + lnum = tmp; + + if (vol->upd_received + count > vol->upd_bytes) + to_write = count = vol->upd_bytes - vol->upd_received; + + /* + * When updating volumes, we accumulate whole logical eraseblock of + * data and write it at once. + */ + if (offs != 0) { + /* + * This is a write to the middle of the logical eraseblock. We + * copy the data to our update buffer and wait for more data or + * flush it if the whole eraseblock is written or the update + * is finished. + */ + + len = vol->usable_leb_size - offs; + if (len > count) + len = count; + + err = copy_from_user(vol->upd_buf + offs, buf, len); + if (err) + return -EFAULT; + + if (offs + len == vol->usable_leb_size || + vol->upd_received + len == vol->upd_bytes) { + int flush_len = offs + len; + + /* + * OK, we gathered either the whole eraseblock or this + * is the last chunk, it's time to flush the buffer. + */ + ubi_assert(flush_len <= vol->usable_leb_size); + err = write_leb(ubi, vol, lnum, vol->upd_buf, flush_len, + vol->upd_ebs); + if (err) + return err; + } + + vol->upd_received += len; + count -= len; + buf += len; + lnum += 1; + } + + /* + * If we've got more to write, let's continue. At this point we know we + * are starting from the beginning of an eraseblock. + */ + while (count) { + if (count > vol->usable_leb_size) + len = vol->usable_leb_size; + else + len = count; + + err = copy_from_user(vol->upd_buf, buf, len); + if (err) + return -EFAULT; + + if (len == vol->usable_leb_size || + vol->upd_received + len == vol->upd_bytes) { + err = write_leb(ubi, vol, lnum, vol->upd_buf, + len, vol->upd_ebs); + if (err) + break; + } + + vol->upd_received += len; + count -= len; + lnum += 1; + buf += len; + } + + ubi_assert(vol->upd_received <= vol->upd_bytes); + if (vol->upd_received == vol->upd_bytes) { + /* The update is finished, clear the update marker */ + err = clear_update_marker(ubi, vol, vol->upd_bytes); + if (err) + return err; + err = ubi_wl_flush(ubi); + if (err == 0) { + vol->updating = 0; + err = to_write; + vfree(vol->upd_buf); + } + } + + return err; +} + +/** + * ubi_more_leb_change_data - accept more data for atomic LEB change. + * @vol: volume description object + * @buf: write data (user-space memory buffer) + * @count: how much bytes to write + * + * This function accepts more data to the volume which is being under the + * "atomic LEB change" operation. It may be called arbitrary number of times + * until all data arrives. This function returns %0 in case of success, number + * of bytes written during the last call if the whole "atomic LEB change" + * operation has been successfully finished, and a negative error code in case + * of failure. + */ +int ubi_more_leb_change_data(struct ubi_device *ubi, struct ubi_volume *vol, + const void __user *buf, int count) +{ + int err; + + dbg_msg("write %d of %lld bytes, %lld already passed", + count, vol->upd_bytes, vol->upd_received); + + if (ubi->ro_mode) + return -EROFS; + + if (vol->upd_received + count > vol->upd_bytes) + count = vol->upd_bytes - vol->upd_received; + + err = copy_from_user(vol->upd_buf + vol->upd_received, buf, count); + if (err) + return -EFAULT; + + vol->upd_received += count; + + if (vol->upd_received == vol->upd_bytes) { + int len = ALIGN((int)vol->upd_bytes, ubi->min_io_size); + + memset(vol->upd_buf + vol->upd_bytes, 0xFF, len - vol->upd_bytes); + len = ubi_calc_data_len(ubi, vol->upd_buf, len); + err = ubi_eba_atomic_leb_change(ubi, vol, vol->ch_lnum, + vol->upd_buf, len, UBI_UNKNOWN); + if (err) + return err; + } + + ubi_assert(vol->upd_received <= vol->upd_bytes); + if (vol->upd_received == vol->upd_bytes) { + vol->changing_leb = 0; + err = count; + vfree(vol->upd_buf); + } + + return err; +} diff --git a/drivers/mtd/ubi/vmt.c b/drivers/mtd/ubi/vmt.c new file mode 100644 index 0000000..c3de51b --- /dev/null +++ b/drivers/mtd/ubi/vmt.c @@ -0,0 +1,866 @@ +/* + * Copyright (c) International Business Machines Corp., 2006 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See + * the GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + * Author: Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file contains implementation of volume creation, deletion, updating and + * resizing. + */ + +#ifdef UBI_LINUX +#include <linux/err.h> +#include <asm/div64.h> +#endif + +#include <ubi_uboot.h> +#include "ubi.h" + +#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID +static void paranoid_check_volumes(struct ubi_device *ubi); +#else +#define paranoid_check_volumes(ubi) +#endif + +#ifdef UBI_LINUX +static ssize_t vol_attribute_show(struct device *dev, + struct device_attribute *attr, char *buf); + +/* Device attributes corresponding to files in '/<sysfs>/class/ubi/ubiX_Y' */ +static struct device_attribute attr_vol_reserved_ebs = + __ATTR(reserved_ebs, S_IRUGO, vol_attribute_show, NULL); +static struct device_attribute attr_vol_type = + __ATTR(type, S_IRUGO, vol_attribute_show, NULL); +static struct device_attribute attr_vol_name = + __ATTR(name, S_IRUGO, vol_attribute_show, NULL); +static struct device_attribute attr_vol_corrupted = + __ATTR(corrupted, S_IRUGO, vol_attribute_show, NULL); +static struct device_attribute attr_vol_alignment = + __ATTR(alignment, S_IRUGO, vol_attribute_show, NULL); +static struct device_attribute attr_vol_usable_eb_size = + __ATTR(usable_eb_size, S_IRUGO, vol_attribute_show, NULL); +static struct device_attribute attr_vol_data_bytes = + __ATTR(data_bytes, S_IRUGO, vol_attribute_show, NULL); +static struct device_attribute attr_vol_upd_marker = + __ATTR(upd_marker, S_IRUGO, vol_attribute_show, NULL); + +/* + * "Show" method for files in '/<sysfs>/class/ubi/ubiX_Y/'. + * + * Consider a situation: + * A. process 1 opens a sysfs file related to volume Y, say + * /<sysfs>/class/ubi/ubiX_Y/reserved_ebs; + * B. process 2 removes volume Y; + * C. process 1 starts reading the /<sysfs>/class/ubi/ubiX_Y/reserved_ebs file; + * + * In this situation, this function will return %-ENODEV because it will find + * out that the volume was removed from the @ubi->volumes array. + */ +static ssize_t vol_attribute_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int ret; + struct ubi_volume *vol = container_of(dev, struct ubi_volume, dev); + struct ubi_device *ubi; + + ubi = ubi_get_device(vol->ubi->ubi_num); + if (!ubi) + return -ENODEV; + + spin_lock(&ubi->volumes_lock); + if (!ubi->volumes[vol->vol_id]) { + spin_unlock(&ubi->volumes_lock); + ubi_put_device(ubi); + return -ENODEV; + } + /* Take a reference to prevent volume removal */ + vol->ref_count += 1; + spin_unlock(&ubi->volumes_lock); + + if (attr == &attr_vol_reserved_ebs) + ret = sprintf(buf, "%d\n", vol->reserved_pebs); + else if (attr == &attr_vol_type) { + const char *tp; + + if (vol->vol_type == UBI_DYNAMIC_VOLUME) + tp = "dynamic"; + else + tp = "static"; + ret = sprintf(buf, "%s\n", tp); + } else if (attr == &attr_vol_name) + ret = sprintf(buf, "%s\n", vol->name); + else if (attr == &attr_vol_corrupted) + ret = sprintf(buf, "%d\n", vol->corrupted); + else if (attr == &attr_vol_alignment) + ret = sprintf(buf, "%d\n", vol->alignment); + else if (attr == &attr_vol_usable_eb_size) + ret = sprintf(buf, "%d\n", vol->usable_leb_size); + else if (attr == &attr_vol_data_bytes) + ret = sprintf(buf, "%lld\n", vol->used_bytes); + else if (attr == &attr_vol_upd_marker) + ret = sprintf(buf, "%d\n", vol->upd_marker); + else + /* This must be a bug */ + ret = -EINVAL; + + /* We've done the operation, drop volume and UBI device references */ + spin_lock(&ubi->volumes_lock); + vol->ref_count -= 1; + ubi_assert(vol->ref_count >= 0); + spin_unlock(&ubi->volumes_lock); + ubi_put_device(ubi); + return ret; +} +#endif + +/* Release method for volume devices */ +static void vol_release(struct device *dev) +{ + struct ubi_volume *vol = container_of(dev, struct ubi_volume, dev); + + kfree(vol); +} + +#ifdef UBI_LINUX +/** + * volume_sysfs_init - initialize sysfs for new volume. + * @ubi: UBI device description object + * @vol: volume description object + * + * This function returns zero in case of success and a negative error code in + * case of failure. + * + * Note, this function does not free allocated resources in case of failure - + * the caller does it. This is because this would cause release() here and the + * caller would oops. + */ +static int volume_sysfs_init(struct ubi_device *ubi, struct ubi_volume *vol) +{ + int err; + + err = device_create_file(&vol->dev, &attr_vol_reserved_ebs); + if (err) + return err; + err = device_create_file(&vol->dev, &attr_vol_type); + if (err) + return err; + err = device_create_file(&vol->dev, &attr_vol_name); + if (err) + return err; + err = device_create_file(&vol->dev, &attr_vol_corrupted); + if (err) + return err; + err = device_create_file(&vol->dev, &attr_vol_alignment); + if (err) + return err; + err = device_create_file(&vol->dev, &attr_vol_usable_eb_size); + if (err) + return err; + err = device_create_file(&vol->dev, &attr_vol_data_bytes); + if (err) + return err; + err = device_create_file(&vol->dev, &attr_vol_upd_marker); + return err; +} + +/** + * volume_sysfs_close - close sysfs for a volume. + * @vol: volume description object + */ +static void volume_sysfs_close(struct ubi_volume *vol) +{ + device_remove_file(&vol->dev, &attr_vol_upd_marker); + device_remove_file(&vol->dev, &attr_vol_data_bytes); + device_remove_file(&vol->dev, &attr_vol_usable_eb_size); + device_remove_file(&vol->dev, &attr_vol_alignment); + device_remove_file(&vol->dev, &attr_vol_corrupted); + device_remove_file(&vol->dev, &attr_vol_name); + device_remove_file(&vol->dev, &attr_vol_type); + device_remove_file(&vol->dev, &attr_vol_reserved_ebs); + device_unregister(&vol->dev); +} +#endif + +/** + * ubi_create_volume - create volume. + * @ubi: UBI device description object + * @req: volume creation request + * + * This function creates volume described by @req. If @req->vol_id id + * %UBI_VOL_NUM_AUTO, this function automatically assign ID to the new volume + * and saves it in @req->vol_id. Returns zero in case of success and a negative + * error code in case of failure. Note, the caller has to have the + * @ubi->volumes_mutex locked. + */ +int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req) +{ + int i, err, vol_id = req->vol_id, dont_free = 0; + struct ubi_volume *vol; + struct ubi_vtbl_record vtbl_rec; + uint64_t bytes; + dev_t dev; + + if (ubi->ro_mode) + return -EROFS; + + vol = kzalloc(sizeof(struct ubi_volume), GFP_KERNEL); + if (!vol) + return -ENOMEM; + + spin_lock(&ubi->volumes_lock); + if (vol_id == UBI_VOL_NUM_AUTO) { + /* Find unused volume ID */ + dbg_msg("search for vacant volume ID"); + for (i = 0; i < ubi->vtbl_slots; i++) + if (!ubi->volumes[i]) { + vol_id = i; + break; + } + + if (vol_id == UBI_VOL_NUM_AUTO) { + dbg_err("out of volume IDs"); + err = -ENFILE; + goto out_unlock; + } + req->vol_id = vol_id; + } + + dbg_msg("volume ID %d, %llu bytes, type %d, name %s", + vol_id, (unsigned long long)req->bytes, + (int)req->vol_type, req->name); + + /* Ensure that this volume does not exist */ + err = -EEXIST; + if (ubi->volumes[vol_id]) { + dbg_err("volume %d already exists", vol_id); + goto out_unlock; + } + + /* Ensure that the name is unique */ + for (i = 0; i < ubi->vtbl_slots; i++) + if (ubi->volumes[i] && + ubi->volumes[i]->name_len == req->name_len && + !strcmp(ubi->volumes[i]->name, req->name)) { + dbg_err("volume "%s" exists (ID %d)", req->name, i); + goto out_unlock; + } + + /* Calculate how many eraseblocks are requested */ + vol->usable_leb_size = ubi->leb_size - ubi->leb_size % req->alignment; + bytes = req->bytes; + if (do_div(bytes, vol->usable_leb_size)) + vol->reserved_pebs = 1; + vol->reserved_pebs += bytes; + + /* Reserve physical eraseblocks */ + if (vol->reserved_pebs > ubi->avail_pebs) { + dbg_err("not enough PEBs, only %d available", ubi->avail_pebs); + err = -ENOSPC; + goto out_unlock; + } + ubi->avail_pebs -= vol->reserved_pebs; + ubi->rsvd_pebs += vol->reserved_pebs; + spin_unlock(&ubi->volumes_lock); + + vol->vol_id = vol_id; + vol->alignment = req->alignment; + vol->data_pad = ubi->leb_size % vol->alignment; + vol->vol_type = req->vol_type; + vol->name_len = req->name_len; + memcpy(vol->name, req->name, vol->name_len + 1); + vol->ubi = ubi; + + /* + * Finish all pending erases because there may be some LEBs belonging + * to the same volume ID. + */ + err = ubi_wl_flush(ubi); + if (err) + goto out_acc; + + vol->eba_tbl = kmalloc(vol->reserved_pebs * sizeof(int), GFP_KERNEL); + if (!vol->eba_tbl) { + err = -ENOMEM; + goto out_acc; + } + + for (i = 0; i < vol->reserved_pebs; i++) + vol->eba_tbl[i] = UBI_LEB_UNMAPPED; + + if (vol->vol_type == UBI_DYNAMIC_VOLUME) { + vol->used_ebs = vol->reserved_pebs; + vol->last_eb_bytes = vol->usable_leb_size; + vol->used_bytes = + (long long)vol->used_ebs * vol->usable_leb_size; + } else { + bytes = vol->used_bytes; + vol->last_eb_bytes = do_div(bytes, vol->usable_leb_size); + vol->used_ebs = bytes; + if (vol->last_eb_bytes) + vol->used_ebs += 1; + else + vol->last_eb_bytes = vol->usable_leb_size; + } + + /* Register character device for the volume */ + cdev_init(&vol->cdev, &ubi_vol_cdev_operations); + vol->cdev.owner = THIS_MODULE; + dev = MKDEV(MAJOR(ubi->cdev.dev), vol_id + 1); + err = cdev_add(&vol->cdev, dev, 1); + if (err) { + ubi_err("cannot add character device"); + goto out_mapping; + } + + err = ubi_create_gluebi(ubi, vol); + if (err) + goto out_cdev; + + vol->dev.release = vol_release; + vol->dev.parent = &ubi->dev; + vol->dev.devt = dev; + vol->dev.class = ubi_class; + +#ifdef UBI_LINUX + sprintf(&vol->dev.bus_id[0], "%s_%d", ubi->ubi_name, vol->vol_id); +#endif + err = device_register(&vol->dev); + if (err) { + ubi_err("cannot register device"); + goto out_gluebi; + } + + err = volume_sysfs_init(ubi, vol); + if (err) + goto out_sysfs; + + /* Fill volume table record */ + memset(&vtbl_rec, 0, sizeof(struct ubi_vtbl_record)); + vtbl_rec.reserved_pebs = cpu_to_be32(vol->reserved_pebs); + vtbl_rec.alignment = cpu_to_be32(vol->alignment); + vtbl_rec.data_pad = cpu_to_be32(vol->data_pad); + vtbl_rec.name_len = cpu_to_be16(vol->name_len); + if (vol->vol_type == UBI_DYNAMIC_VOLUME) + vtbl_rec.vol_type = UBI_VID_DYNAMIC; + else + vtbl_rec.vol_type = UBI_VID_STATIC; + memcpy(vtbl_rec.name, vol->name, vol->name_len + 1); + + err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec); + if (err) + goto out_sysfs; + + spin_lock(&ubi->volumes_lock); + ubi->volumes[vol_id] = vol; + ubi->vol_count += 1; + spin_unlock(&ubi->volumes_lock); + + paranoid_check_volumes(ubi); + return 0; + +out_sysfs: + /* + * We have registered our device, we should not free the volume* + * description object in this function in case of an error - it is + * freed by the release function. + * + * Get device reference to prevent the release function from being + * called just after sysfs has been closed. + */ + dont_free = 1; + get_device(&vol->dev); + volume_sysfs_close(vol); +out_gluebi: + if (ubi_destroy_gluebi(vol)) + dbg_err("cannot destroy gluebi for volume %d:%d", + ubi->ubi_num, vol_id); +out_cdev: + cdev_del(&vol->cdev); +out_mapping: + kfree(vol->eba_tbl); +out_acc: + spin_lock(&ubi->volumes_lock); + ubi->rsvd_pebs -= vol->reserved_pebs; + ubi->avail_pebs += vol->reserved_pebs; +out_unlock: + spin_unlock(&ubi->volumes_lock); + if (dont_free) + put_device(&vol->dev); + else + kfree(vol); + ubi_err("cannot create volume %d, error %d", vol_id, err); + return err; +} + +/** + * ubi_remove_volume - remove volume. + * @desc: volume descriptor + * + * This function removes volume described by @desc. The volume has to be opened + * in "exclusive" mode. Returns zero in case of success and a negative error + * code in case of failure. The caller has to have the @ubi->volumes_mutex + * locked. + */ +int ubi_remove_volume(struct ubi_volume_desc *desc) +{ + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + int i, err, vol_id = vol->vol_id, reserved_pebs = vol->reserved_pebs; + + dbg_msg("remove UBI volume %d", vol_id); + ubi_assert(desc->mode == UBI_EXCLUSIVE); + ubi_assert(vol == ubi->volumes[vol_id]); + + if (ubi->ro_mode) + return -EROFS; + + spin_lock(&ubi->volumes_lock); + if (vol->ref_count > 1) { + /* + * The volume is busy, probably someone is reading one of its + * sysfs files. + */ + err = -EBUSY; + goto out_unlock; + } + ubi->volumes[vol_id] = NULL; + spin_unlock(&ubi->volumes_lock); + + err = ubi_destroy_gluebi(vol); + if (err) + goto out_err; + + err = ubi_change_vtbl_record(ubi, vol_id, NULL); + if (err) + goto out_err; + + for (i = 0; i < vol->reserved_pebs; i++) { + err = ubi_eba_unmap_leb(ubi, vol, i); + if (err) + goto out_err; + } + + kfree(vol->eba_tbl); + vol->eba_tbl = NULL; + cdev_del(&vol->cdev); + volume_sysfs_close(vol); + + spin_lock(&ubi->volumes_lock); + ubi->rsvd_pebs -= reserved_pebs; + ubi->avail_pebs += reserved_pebs; + i = ubi->beb_rsvd_level - ubi->beb_rsvd_pebs; + if (i > 0) { + i = ubi->avail_pebs >= i ? i : ubi->avail_pebs; + ubi->avail_pebs -= i; + ubi->rsvd_pebs += i; + ubi->beb_rsvd_pebs += i; + if (i > 0) + ubi_msg("reserve more %d PEBs", i); + } + ubi->vol_count -= 1; + spin_unlock(&ubi->volumes_lock); + + paranoid_check_volumes(ubi); + return 0; + +out_err: + ubi_err("cannot remove volume %d, error %d", vol_id, err); + spin_lock(&ubi->volumes_lock); + ubi->volumes[vol_id] = vol; +out_unlock: + spin_unlock(&ubi->volumes_lock); + return err; +} + +/** + * ubi_resize_volume - re-size volume. + * @desc: volume descriptor + * @reserved_pebs: new size in physical eraseblocks + * + * This function re-sizes the volume and returns zero in case of success, and a + * negative error code in case of failure. The caller has to have the + * @ubi->volumes_mutex locked. + */ +int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs) +{ + int i, err, pebs, *new_mapping; + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + struct ubi_vtbl_record vtbl_rec; + int vol_id = vol->vol_id; + + if (ubi->ro_mode) + return -EROFS; + + dbg_msg("re-size volume %d to from %d to %d PEBs", + vol_id, vol->reserved_pebs, reserved_pebs); + + if (vol->vol_type == UBI_STATIC_VOLUME && + reserved_pebs < vol->used_ebs) { + dbg_err("too small size %d, %d LEBs contain data", + reserved_pebs, vol->used_ebs); + return -EINVAL; + } + + /* If the size is the same, we have nothing to do */ + if (reserved_pebs == vol->reserved_pebs) + return 0; + + new_mapping = kmalloc(reserved_pebs * sizeof(int), GFP_KERNEL); + if (!new_mapping) + return -ENOMEM; + + for (i = 0; i < reserved_pebs; i++) + new_mapping[i] = UBI_LEB_UNMAPPED; + + spin_lock(&ubi->volumes_lock); + if (vol->ref_count > 1) { + spin_unlock(&ubi->volumes_lock); + err = -EBUSY; + goto out_free; + } + spin_unlock(&ubi->volumes_lock); + + /* Reserve physical eraseblocks */ + pebs = reserved_pebs - vol->reserved_pebs; + if (pebs > 0) { + spin_lock(&ubi->volumes_lock); + if (pebs > ubi->avail_pebs) { + dbg_err("not enough PEBs: requested %d, available %d", + pebs, ubi->avail_pebs); + spin_unlock(&ubi->volumes_lock); + err = -ENOSPC; + goto out_free; + } + ubi->avail_pebs -= pebs; + ubi->rsvd_pebs += pebs; + for (i = 0; i < vol->reserved_pebs; i++) + new_mapping[i] = vol->eba_tbl[i]; + kfree(vol->eba_tbl); + vol->eba_tbl = new_mapping; + spin_unlock(&ubi->volumes_lock); + } + + /* Change volume table record */ + memcpy(&vtbl_rec, &ubi->vtbl[vol_id], sizeof(struct ubi_vtbl_record)); + vtbl_rec.reserved_pebs = cpu_to_be32(reserved_pebs); + err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec); + if (err) + goto out_acc; + + if (pebs < 0) { + for (i = 0; i < -pebs; i++) { + err = ubi_eba_unmap_leb(ubi, vol, reserved_pebs + i); + if (err) + goto out_acc; + } + spin_lock(&ubi->volumes_lock); + ubi->rsvd_pebs += pebs; + ubi->avail_pebs -= pebs; + pebs = ubi->beb_rsvd_level - ubi->beb_rsvd_pebs; + if (pebs > 0) { + pebs = ubi->avail_pebs >= pebs ? pebs : ubi->avail_pebs; + ubi->avail_pebs -= pebs; + ubi->rsvd_pebs += pebs; + ubi->beb_rsvd_pebs += pebs; + if (pebs > 0) + ubi_msg("reserve more %d PEBs", pebs); + } + for (i = 0; i < reserved_pebs; i++) + new_mapping[i] = vol->eba_tbl[i]; + kfree(vol->eba_tbl); + vol->eba_tbl = new_mapping; + spin_unlock(&ubi->volumes_lock); + } + + vol->reserved_pebs = reserved_pebs; + if (vol->vol_type == UBI_DYNAMIC_VOLUME) { + vol->used_ebs = reserved_pebs; + vol->last_eb_bytes = vol->usable_leb_size; + vol->used_bytes = + (long long)vol->used_ebs * vol->usable_leb_size; + } + + paranoid_check_volumes(ubi); + return 0; + +out_acc: + if (pebs > 0) { + spin_lock(&ubi->volumes_lock); + ubi->rsvd_pebs -= pebs; + ubi->avail_pebs += pebs; + spin_unlock(&ubi->volumes_lock); + } +out_free: + kfree(new_mapping); + return err; +} + +/** + * ubi_add_volume - add volume. + * @ubi: UBI device description object + * @vol: volume description object + * + * This function adds an existing volume and initializes all its data + * structures. Returns zero in case of success and a negative error code in + * case of failure. + */ +int ubi_add_volume(struct ubi_device *ubi, struct ubi_volume *vol) +{ + int err, vol_id = vol->vol_id; + dev_t dev; + + dbg_msg("add volume %d", vol_id); + ubi_dbg_dump_vol_info(vol); + + /* Register character device for the volume */ + cdev_init(&vol->cdev, &ubi_vol_cdev_operations); + vol->cdev.owner = THIS_MODULE; + dev = MKDEV(MAJOR(ubi->cdev.dev), vol->vol_id + 1); + err = cdev_add(&vol->cdev, dev, 1); + if (err) { + ubi_err("cannot add character device for volume %d, error %d", + vol_id, err); + return err; + } + + err = ubi_create_gluebi(ubi, vol); + if (err) + goto out_cdev; + + vol->dev.release = vol_release; + vol->dev.parent = &ubi->dev; + vol->dev.devt = dev; + vol->dev.class = ubi_class; +#ifdef UBI_LINUX + sprintf(&vol->dev.bus_id[0], "%s_%d", ubi->ubi_name, vol->vol_id); +#endif + err = device_register(&vol->dev); + if (err) + goto out_gluebi; + + err = volume_sysfs_init(ubi, vol); + if (err) { + cdev_del(&vol->cdev); + err = ubi_destroy_gluebi(vol); + volume_sysfs_close(vol); + return err; + } + + paranoid_check_volumes(ubi); + return 0; + +out_gluebi: + err = ubi_destroy_gluebi(vol); +out_cdev: + cdev_del(&vol->cdev); + return err; +} + +/** + * ubi_free_volume - free volume. + * @ubi: UBI device description object + * @vol: volume description object + * + * This function frees all resources for volume @vol but does not remove it. + * Used only when the UBI device is detached. + */ +void ubi_free_volume(struct ubi_device *ubi, struct ubi_volume *vol) +{ + int err; + + dbg_msg("free volume %d", vol->vol_id); + + ubi->volumes[vol->vol_id] = NULL; + err = ubi_destroy_gluebi(vol); + cdev_del(&vol->cdev); + volume_sysfs_close(vol); +} + +#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID + +/** + * paranoid_check_volume - check volume information. + * @ubi: UBI device description object + * @vol_id: volume ID + */ +static void paranoid_check_volume(struct ubi_device *ubi, int vol_id) +{ + int idx = vol_id2idx(ubi, vol_id); + int reserved_pebs, alignment, data_pad, vol_type, name_len, upd_marker; + const struct ubi_volume *vol; + long long n; + const char *name; + + spin_lock(&ubi->volumes_lock); + reserved_pebs = be32_to_cpu(ubi->vtbl[vol_id].reserved_pebs); + vol = ubi->volumes[idx]; + + if (!vol) { + if (reserved_pebs) { + ubi_err("no volume info, but volume exists"); + goto fail; + } + spin_unlock(&ubi->volumes_lock); + return; + } + + if (vol->exclusive) { + /* + * The volume may be being created at the moment, do not check + * it (e.g., it may be in the middle of ubi_create_volume(). + */ + spin_unlock(&ubi->volumes_lock); + return; + } + + if (vol->reserved_pebs < 0 || vol->alignment < 0 || vol->data_pad < 0 || + vol->name_len < 0) { + ubi_err("negative values"); + goto fail; + } + if (vol->alignment > ubi->leb_size || vol->alignment == 0) { + ubi_err("bad alignment"); + goto fail; + } + + n = vol->alignment & (ubi->min_io_size - 1); + if (vol->alignment != 1 && n) { + ubi_err("alignment is not multiple of min I/O unit"); + goto fail; + } + + n = ubi->leb_size % vol->alignment; + if (vol->data_pad != n) { + ubi_err("bad data_pad, has to be %lld", n); + goto fail; + } + + if (vol->vol_type != UBI_DYNAMIC_VOLUME && + vol->vol_type != UBI_STATIC_VOLUME) { + ubi_err("bad vol_type"); + goto fail; + } + + if (vol->upd_marker && vol->corrupted) { + dbg_err("update marker and corrupted simultaneously"); + goto fail; + } + + if (vol->reserved_pebs > ubi->good_peb_count) { + ubi_err("too large reserved_pebs"); + goto fail; + } + + n = ubi->leb_size - vol->data_pad; + if (vol->usable_leb_size != ubi->leb_size - vol->data_pad) { + ubi_err("bad usable_leb_size, has to be %lld", n); + goto fail; + } + + if (vol->name_len > UBI_VOL_NAME_MAX) { + ubi_err("too long volume name, max is %d", UBI_VOL_NAME_MAX); + goto fail; + } + + if (!vol->name) { + ubi_err("NULL volume name"); + goto fail; + } + + n = strnlen(vol->name, vol->name_len + 1); + if (n != vol->name_len) { + ubi_err("bad name_len %lld", n); + goto fail; + } + + n = (long long)vol->used_ebs * vol->usable_leb_size; + if (vol->vol_type == UBI_DYNAMIC_VOLUME) { + if (vol->corrupted) { + ubi_err("corrupted dynamic volume"); + goto fail; + } + if (vol->used_ebs != vol->reserved_pebs) { + ubi_err("bad used_ebs"); + goto fail; + } + if (vol->last_eb_bytes != vol->usable_leb_size) { + ubi_err("bad last_eb_bytes"); + goto fail; + } + if (vol->used_bytes != n) { + ubi_err("bad used_bytes"); + goto fail; + } + } else { + if (vol->used_ebs < 0 || vol->used_ebs > vol->reserved_pebs) { + ubi_err("bad used_ebs"); + goto fail; + } + if (vol->last_eb_bytes < 0 || + vol->last_eb_bytes > vol->usable_leb_size) { + ubi_err("bad last_eb_bytes"); + goto fail; + } + if (vol->used_bytes < 0 || vol->used_bytes > n || + vol->used_bytes < n - vol->usable_leb_size) { + ubi_err("bad used_bytes"); + goto fail; + } + } + + alignment = be32_to_cpu(ubi->vtbl[vol_id].alignment); + data_pad = be32_to_cpu(ubi->vtbl[vol_id].data_pad); + name_len = be16_to_cpu(ubi->vtbl[vol_id].name_len); + upd_marker = ubi->vtbl[vol_id].upd_marker; + name = &ubi->vtbl[vol_id].name[0]; + if (ubi->vtbl[vol_id].vol_type == UBI_VID_DYNAMIC) + vol_type = UBI_DYNAMIC_VOLUME; + else + vol_type = UBI_STATIC_VOLUME; + + if (alignment != vol->alignment || data_pad != vol->data_pad || + upd_marker != vol->upd_marker || vol_type != vol->vol_type || + name_len != vol->name_len || strncmp(name, vol->name, name_len)) { + ubi_err("volume info is different"); + goto fail; + } + + spin_unlock(&ubi->volumes_lock); + return; + +fail: + ubi_err("paranoid check failed for volume %d", vol_id); + ubi_dbg_dump_vol_info(vol); + ubi_dbg_dump_vtbl_record(&ubi->vtbl[vol_id], vol_id); + spin_unlock(&ubi->volumes_lock); + BUG(); +} + +/** + * paranoid_check_volumes - check information about all volumes. + * @ubi: UBI device description object + */ +static void paranoid_check_volumes(struct ubi_device *ubi) +{ + int i; + + for (i = 0; i < ubi->vtbl_slots; i++) + paranoid_check_volume(ubi, i); +} +#endif diff --git a/drivers/mtd/ubi/vtbl.c b/drivers/mtd/ubi/vtbl.c new file mode 100644 index 0000000..2aa5532 --- /dev/null +++ b/drivers/mtd/ubi/vtbl.c @@ -0,0 +1,838 @@ +/* + * Copyright (c) International Business Machines Corp., 2006 + * Copyright (c) Nokia Corporation, 2006, 2007 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See + * the GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + * Author: Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file includes volume table manipulation code. The volume table is an + * on-flash table containing volume meta-data like name, number of reserved + * physical eraseblocks, type, etc. The volume table is stored in the so-called + * "layout volume". + * + * The layout volume is an internal volume which is organized as follows. It + * consists of two logical eraseblocks - LEB 0 and LEB 1. Each logical + * eraseblock stores one volume table copy, i.e. LEB 0 and LEB 1 duplicate each + * other. This redundancy guarantees robustness to unclean reboots. The volume + * table is basically an array of volume table records. Each record contains + * full information about the volume and protected by a CRC checksum. + * + * The volume table is changed, it is first changed in RAM. Then LEB 0 is + * erased, and the updated volume table is written back to LEB 0. Then same for + * LEB 1. This scheme guarantees recoverability from unclean reboots. + * + * In this UBI implementation the on-flash volume table does not contain any + * information about how many data static volumes contain. This information may + * be found from the scanning data. + * + * But it would still be beneficial to store this information in the volume + * table. For example, suppose we have a static volume X, and all its physical + * eraseblocks became bad for some reasons. Suppose we are attaching the + * corresponding MTD device, the scanning has found no logical eraseblocks + * corresponding to the volume X. According to the volume table volume X does + * exist. So we don't know whether it is just empty or all its physical + * eraseblocks went bad. So we cannot alarm the user about this corruption. + * + * The volume table also stores so-called "update marker", which is used for + * volume updates. Before updating the volume, the update marker is set, and + * after the update operation is finished, the update marker is cleared. So if + * the update operation was interrupted (e.g. by an unclean reboot) - the + * update marker is still there and we know that the volume's contents is + * damaged. + */ + +#ifdef UBI_LINUX +#include <linux/crc32.h> +#include <linux/err.h> +#include <asm/div64.h> +#endif + +#include <ubi_uboot.h> +#include "ubi.h" + +#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID +static void paranoid_vtbl_check(const struct ubi_device *ubi); +#else +#define paranoid_vtbl_check(ubi) +#endif + +/* Empty volume table record */ +static struct ubi_vtbl_record empty_vtbl_record; + +/** + * ubi_change_vtbl_record - change volume table record. + * @ubi: UBI device description object + * @idx: table index to change + * @vtbl_rec: new volume table record + * + * This function changes volume table record @idx. If @vtbl_rec is %NULL, empty + * volume table record is written. The caller does not have to calculate CRC of + * the record as it is done by this function. Returns zero in case of success + * and a negative error code in case of failure. + */ +int ubi_change_vtbl_record(struct ubi_device *ubi, int idx, + struct ubi_vtbl_record *vtbl_rec) +{ + int i, err; + uint32_t crc; + struct ubi_volume *layout_vol; + + ubi_assert(idx >= 0 && idx < ubi->vtbl_slots); + layout_vol = ubi->volumes[vol_id2idx(ubi, UBI_LAYOUT_VOLUME_ID)]; + + if (!vtbl_rec) + vtbl_rec = &empty_vtbl_record; + else { + crc = crc32(UBI_CRC32_INIT, vtbl_rec, UBI_VTBL_RECORD_SIZE_CRC); + vtbl_rec->crc = cpu_to_be32(crc); + } + + memcpy(&ubi->vtbl[idx], vtbl_rec, sizeof(struct ubi_vtbl_record)); + for (i = 0; i < UBI_LAYOUT_VOLUME_EBS; i++) { + err = ubi_eba_unmap_leb(ubi, layout_vol, i); + if (err) + return err; + + err = ubi_eba_write_leb(ubi, layout_vol, i, ubi->vtbl, 0, + ubi->vtbl_size, UBI_LONGTERM); + if (err) + return err; + } + + paranoid_vtbl_check(ubi); + return 0; +} + +/** + * vtbl_check - check if volume table is not corrupted and contains sensible + * data. + * @ubi: UBI device description object + * @vtbl: volume table + * + * This function returns zero if @vtbl is all right, %1 if CRC is incorrect, + * and %-EINVAL if it contains inconsistent data. + */ +static int vtbl_check(const struct ubi_device *ubi, + const struct ubi_vtbl_record *vtbl) +{ + int i, n, reserved_pebs, alignment, data_pad, vol_type, name_len; + int upd_marker, err; + uint32_t crc; + const char *name; + + for (i = 0; i < ubi->vtbl_slots; i++) { + cond_resched(); + + reserved_pebs = be32_to_cpu(vtbl[i].reserved_pebs); + alignment = be32_to_cpu(vtbl[i].alignment); + data_pad = be32_to_cpu(vtbl[i].data_pad); + upd_marker = vtbl[i].upd_marker; + vol_type = vtbl[i].vol_type; + name_len = be16_to_cpu(vtbl[i].name_len); + name = (const char *) &vtbl[i].name[0]; + + crc = crc32(UBI_CRC32_INIT, &vtbl[i], UBI_VTBL_RECORD_SIZE_CRC); + if (be32_to_cpu(vtbl[i].crc) != crc) { + ubi_err("bad CRC at record %u: %#08x, not %#08x", + i, crc, be32_to_cpu(vtbl[i].crc)); + ubi_dbg_dump_vtbl_record(&vtbl[i], i); + return 1; + } + + if (reserved_pebs == 0) { + if (memcmp(&vtbl[i], &empty_vtbl_record, + UBI_VTBL_RECORD_SIZE)) { + err = 2; + goto bad; + } + continue; + } + + if (reserved_pebs < 0 || alignment < 0 || data_pad < 0 || + name_len < 0) { + err = 3; + goto bad; + } + + if (alignment > ubi->leb_size || alignment == 0) { + err = 4; + goto bad; + } + + n = alignment & (ubi->min_io_size - 1); + if (alignment != 1 && n) { + err = 5; + goto bad; + } + + n = ubi->leb_size % alignment; + if (data_pad != n) { + dbg_err("bad data_pad, has to be %d", n); + err = 6; + goto bad; + } + + if (vol_type != UBI_VID_DYNAMIC && vol_type != UBI_VID_STATIC) { + err = 7; + goto bad; + } + + if (upd_marker != 0 && upd_marker != 1) { + err = 8; + goto bad; + } + + if (reserved_pebs > ubi->good_peb_count) { + dbg_err("too large reserved_pebs, good PEBs %d", + ubi->good_peb_count); + err = 9; + goto bad; + } + + if (name_len > UBI_VOL_NAME_MAX) { + err = 10; + goto bad; + } + + if (name[0] == '\0') { + err = 11; + goto bad; + } + + if (name_len != strnlen(name, name_len + 1)) { + err = 12; + goto bad; + } + } + + /* Checks that all names are unique */ + for (i = 0; i < ubi->vtbl_slots - 1; i++) { + for (n = i + 1; n < ubi->vtbl_slots; n++) { + int len1 = be16_to_cpu(vtbl[i].name_len); + int len2 = be16_to_cpu(vtbl[n].name_len); + + if (len1 > 0 && len1 == len2 && + !strncmp((const char *) vtbl[i].name, + (const char *) vtbl[n].name, len1)) { + ubi_err("volumes %d and %d have the same name" + " "%s"", i, n, vtbl[i].name); + ubi_dbg_dump_vtbl_record(&vtbl[i], i); + ubi_dbg_dump_vtbl_record(&vtbl[n], n); + return -EINVAL; + } + } + } + + return 0; + +bad: + ubi_err("volume table check failed: record %d, error %d", i, err); + ubi_dbg_dump_vtbl_record(&vtbl[i], i); + return -EINVAL; +} + +/** + * create_vtbl - create a copy of volume table. + * @ubi: UBI device description object + * @si: scanning information + * @copy: number of the volume table copy + * @vtbl: contents of the volume table + * + * This function returns zero in case of success and a negative error code in + * case of failure. + */ +static int create_vtbl(struct ubi_device *ubi, struct ubi_scan_info *si, + int copy, void *vtbl) +{ + int err, tries = 0; + static struct ubi_vid_hdr *vid_hdr; + struct ubi_scan_volume *sv; + struct ubi_scan_leb *new_seb, *old_seb = NULL; + + ubi_msg("create volume table (copy #%d)", copy + 1); + + vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL); + if (!vid_hdr) + return -ENOMEM; + + /* + * Check if there is a logical eraseblock which would have to contain + * this volume table copy was found during scanning. It has to be wiped + * out. + */ + sv = ubi_scan_find_sv(si, UBI_LAYOUT_VOLUME_ID); + if (sv) + old_seb = ubi_scan_find_seb(sv, copy); + +retry: + new_seb = ubi_scan_get_free_peb(ubi, si); + if (IS_ERR(new_seb)) { + err = PTR_ERR(new_seb); + goto out_free; + } + + vid_hdr->vol_type = UBI_VID_DYNAMIC; + vid_hdr->vol_id = cpu_to_be32(UBI_LAYOUT_VOLUME_ID); + vid_hdr->compat = UBI_LAYOUT_VOLUME_COMPAT; + vid_hdr->data_size = vid_hdr->used_ebs = + vid_hdr->data_pad = cpu_to_be32(0); + vid_hdr->lnum = cpu_to_be32(copy); + vid_hdr->sqnum = cpu_to_be64(++si->max_sqnum); + vid_hdr->leb_ver = cpu_to_be32(old_seb ? old_seb->leb_ver + 1: 0); + + /* The EC header is already there, write the VID header */ + err = ubi_io_write_vid_hdr(ubi, new_seb->pnum, vid_hdr); + if (err) + goto write_error; + + /* Write the layout volume contents */ + err = ubi_io_write_data(ubi, vtbl, new_seb->pnum, 0, ubi->vtbl_size); + if (err) + goto write_error; + + /* + * And add it to the scanning information. Don't delete the old + * @old_seb as it will be deleted and freed in 'ubi_scan_add_used()'. + */ + err = ubi_scan_add_used(ubi, si, new_seb->pnum, new_seb->ec, + vid_hdr, 0); + kfree(new_seb); + ubi_free_vid_hdr(ubi, vid_hdr); + return err; + +write_error: + if (err == -EIO && ++tries <= 5) { + /* + * Probably this physical eraseblock went bad, try to pick + * another one. + */ + list_add_tail(&new_seb->u.list, &si->corr); + goto retry; + } + kfree(new_seb); +out_free: + ubi_free_vid_hdr(ubi, vid_hdr); + return err; + +} + +/** + * process_lvol - process the layout volume. + * @ubi: UBI device description object + * @si: scanning information + * @sv: layout volume scanning information + * + * This function is responsible for reading the layout volume, ensuring it is + * not corrupted, and recovering from corruptions if needed. Returns volume + * table in case of success and a negative error code in case of failure. + */ +static struct ubi_vtbl_record *process_lvol(struct ubi_device *ubi, + struct ubi_scan_info *si, + struct ubi_scan_volume *sv) +{ + int err; + struct rb_node *rb; + struct ubi_scan_leb *seb; + struct ubi_vtbl_record *leb[UBI_LAYOUT_VOLUME_EBS] = { NULL, NULL }; + int leb_corrupted[UBI_LAYOUT_VOLUME_EBS] = {1, 1}; + + /* + * UBI goes through the following steps when it changes the layout + * volume: + * a. erase LEB 0; + * b. write new data to LEB 0; + * c. erase LEB 1; + * d. write new data to LEB 1. + * + * Before the change, both LEBs contain the same data. + * + * Due to unclean reboots, the contents of LEB 0 may be lost, but there + * should LEB 1. So it is OK if LEB 0 is corrupted while LEB 1 is not. + * Similarly, LEB 1 may be lost, but there should be LEB 0. And + * finally, unclean reboots may result in a situation when neither LEB + * 0 nor LEB 1 are corrupted, but they are different. In this case, LEB + * 0 contains more recent information. + * + * So the plan is to first check LEB 0. Then + * a. if LEB 0 is OK, it must be containing the most resent data; then + * we compare it with LEB 1, and if they are different, we copy LEB + * 0 to LEB 1; + * b. if LEB 0 is corrupted, but LEB 1 has to be OK, and we copy LEB 1 + * to LEB 0. + */ + + dbg_msg("check layout volume"); + + /* Read both LEB 0 and LEB 1 into memory */ + ubi_rb_for_each_entry(rb, seb, &sv->root, u.rb) { + leb[seb->lnum] = vmalloc(ubi->vtbl_size); + if (!leb[seb->lnum]) { + err = -ENOMEM; + goto out_free; + } + memset(leb[seb->lnum], 0, ubi->vtbl_size); + + err = ubi_io_read_data(ubi, leb[seb->lnum], seb->pnum, 0, + ubi->vtbl_size); + if (err == UBI_IO_BITFLIPS || err == -EBADMSG) + /* + * Scrub the PEB later. Note, -EBADMSG indicates an + * uncorrectable ECC error, but we have our own CRC and + * the data will be checked later. If the data is OK, + * the PEB will be scrubbed (because we set + * seb->scrub). If the data is not OK, the contents of + * the PEB will be recovered from the second copy, and + * seb->scrub will be cleared in + * 'ubi_scan_add_used()'. + */ + seb->scrub = 1; + else if (err) + goto out_free; + } + + err = -EINVAL; + if (leb[0]) { + leb_corrupted[0] = vtbl_check(ubi, leb[0]); + if (leb_corrupted[0] < 0) + goto out_free; + } + + if (!leb_corrupted[0]) { + /* LEB 0 is OK */ + if (leb[1]) + leb_corrupted[1] = memcmp(leb[0], leb[1], ubi->vtbl_size); + if (leb_corrupted[1]) { + ubi_warn("volume table copy #2 is corrupted"); + err = create_vtbl(ubi, si, 1, leb[0]); + if (err) + goto out_free; + ubi_msg("volume table was restored"); + } + + /* Both LEB 1 and LEB 2 are OK and consistent */ + vfree(leb[1]); + return leb[0]; + } else { + /* LEB 0 is corrupted or does not exist */ + if (leb[1]) { + leb_corrupted[1] = vtbl_check(ubi, leb[1]); + if (leb_corrupted[1] < 0) + goto out_free; + } + if (leb_corrupted[1]) { + /* Both LEB 0 and LEB 1 are corrupted */ + ubi_err("both volume tables are corrupted"); + goto out_free; + } + + ubi_warn("volume table copy #1 is corrupted"); + err = create_vtbl(ubi, si, 0, leb[1]); + if (err) + goto out_free; + ubi_msg("volume table was restored"); + + vfree(leb[0]); + return leb[1]; + } + +out_free: + vfree(leb[0]); + vfree(leb[1]); + return ERR_PTR(err); +} + +/** + * create_empty_lvol - create empty layout volume. + * @ubi: UBI device description object + * @si: scanning information + * + * This function returns volume table contents in case of success and a + * negative error code in case of failure. + */ +static struct ubi_vtbl_record *create_empty_lvol(struct ubi_device *ubi, + struct ubi_scan_info *si) +{ + int i; + struct ubi_vtbl_record *vtbl; + + vtbl = vmalloc(ubi->vtbl_size); + if (!vtbl) + return ERR_PTR(-ENOMEM); + memset(vtbl, 0, ubi->vtbl_size); + + for (i = 0; i < ubi->vtbl_slots; i++) + memcpy(&vtbl[i], &empty_vtbl_record, UBI_VTBL_RECORD_SIZE); + + for (i = 0; i < UBI_LAYOUT_VOLUME_EBS; i++) { + int err; + + err = create_vtbl(ubi, si, i, vtbl); + if (err) { + vfree(vtbl); + return ERR_PTR(err); + } + } + + return vtbl; +} + +/** + * init_volumes - initialize volume information for existing volumes. + * @ubi: UBI device description object + * @si: scanning information + * @vtbl: volume table + * + * This function allocates volume description objects for existing volumes. + * Returns zero in case of success and a negative error code in case of + * failure. + */ +static int init_volumes(struct ubi_device *ubi, const struct ubi_scan_info *si, + const struct ubi_vtbl_record *vtbl) +{ + int i, reserved_pebs = 0; + struct ubi_scan_volume *sv; + struct ubi_volume *vol; + + for (i = 0; i < ubi->vtbl_slots; i++) { + cond_resched(); + + if (be32_to_cpu(vtbl[i].reserved_pebs) == 0) + continue; /* Empty record */ + + vol = kzalloc(sizeof(struct ubi_volume), GFP_KERNEL); + if (!vol) + return -ENOMEM; + + vol->reserved_pebs = be32_to_cpu(vtbl[i].reserved_pebs); + vol->alignment = be32_to_cpu(vtbl[i].alignment); + vol->data_pad = be32_to_cpu(vtbl[i].data_pad); + vol->vol_type = vtbl[i].vol_type == UBI_VID_DYNAMIC ? + UBI_DYNAMIC_VOLUME : UBI_STATIC_VOLUME; + vol->name_len = be16_to_cpu(vtbl[i].name_len); + vol->usable_leb_size = ubi->leb_size - vol->data_pad; + memcpy(vol->name, vtbl[i].name, vol->name_len); + vol->name[vol->name_len] = '\0'; + vol->vol_id = i; + + if (vtbl[i].flags & UBI_VTBL_AUTORESIZE_FLG) { + /* Auto re-size flag may be set only for one volume */ + if (ubi->autoresize_vol_id != -1) { + ubi_err("more then one auto-resize volume (%d " + "and %d)", ubi->autoresize_vol_id, i); + kfree(vol); + return -EINVAL; + } + + ubi->autoresize_vol_id = i; + } + + ubi_assert(!ubi->volumes[i]); + ubi->volumes[i] = vol; + ubi->vol_count += 1; + vol->ubi = ubi; + reserved_pebs += vol->reserved_pebs; + + /* + * In case of dynamic volume UBI knows nothing about how many + * data is stored there. So assume the whole volume is used. + */ + if (vol->vol_type == UBI_DYNAMIC_VOLUME) { + vol->used_ebs = vol->reserved_pebs; + vol->last_eb_bytes = vol->usable_leb_size; + vol->used_bytes = + (long long)vol->used_ebs * vol->usable_leb_size; + continue; + } + + /* Static volumes only */ + sv = ubi_scan_find_sv(si, i); + if (!sv) { + /* + * No eraseblocks belonging to this volume found. We + * don't actually know whether this static volume is + * completely corrupted or just contains no data. And + * we cannot know this as long as data size is not + * stored on flash. So we just assume the volume is + * empty. FIXME: this should be handled. + */ + continue; + } + + if (sv->leb_count != sv->used_ebs) { + /* + * We found a static volume which misses several + * eraseblocks. Treat it as corrupted. + */ + ubi_warn("static volume %d misses %d LEBs - corrupted", + sv->vol_id, sv->used_ebs - sv->leb_count); + vol->corrupted = 1; + continue; + } + + vol->used_ebs = sv->used_ebs; + vol->used_bytes = + (long long)(vol->used_ebs - 1) * vol->usable_leb_size; + vol->used_bytes += sv->last_data_size; + vol->last_eb_bytes = sv->last_data_size; + } + + /* And add the layout volume */ + vol = kzalloc(sizeof(struct ubi_volume), GFP_KERNEL); + if (!vol) + return -ENOMEM; + + vol->reserved_pebs = UBI_LAYOUT_VOLUME_EBS; + vol->alignment = 1; + vol->vol_type = UBI_DYNAMIC_VOLUME; + vol->name_len = sizeof(UBI_LAYOUT_VOLUME_NAME) - 1; + memcpy(vol->name, UBI_LAYOUT_VOLUME_NAME, vol->name_len + 1); + vol->usable_leb_size = ubi->leb_size; + vol->used_ebs = vol->reserved_pebs; + vol->last_eb_bytes = vol->reserved_pebs; + vol->used_bytes = + (long long)vol->used_ebs * (ubi->leb_size - vol->data_pad); + vol->vol_id = UBI_LAYOUT_VOLUME_ID; + vol->ref_count = 1; + + ubi_assert(!ubi->volumes[i]); + ubi->volumes[vol_id2idx(ubi, vol->vol_id)] = vol; + reserved_pebs += vol->reserved_pebs; + ubi->vol_count += 1; + vol->ubi = ubi; + + if (reserved_pebs > ubi->avail_pebs) + ubi_err("not enough PEBs, required %d, available %d", + reserved_pebs, ubi->avail_pebs); + ubi->rsvd_pebs += reserved_pebs; + ubi->avail_pebs -= reserved_pebs; + + return 0; +} + +/** + * check_sv - check volume scanning information. + * @vol: UBI volume description object + * @sv: volume scanning information + * + * This function returns zero if the volume scanning information is consistent + * to the data read from the volume tabla, and %-EINVAL if not. + */ +static int check_sv(const struct ubi_volume *vol, + const struct ubi_scan_volume *sv) +{ + int err; + + if (sv->highest_lnum >= vol->reserved_pebs) { + err = 1; + goto bad; + } + if (sv->leb_count > vol->reserved_pebs) { + err = 2; + goto bad; + } + if (sv->vol_type != vol->vol_type) { + err = 3; + goto bad; + } + if (sv->used_ebs > vol->reserved_pebs) { + err = 4; + goto bad; + } + if (sv->data_pad != vol->data_pad) { + err = 5; + goto bad; + } + return 0; + +bad: + ubi_err("bad scanning information, error %d", err); + ubi_dbg_dump_sv(sv); + ubi_dbg_dump_vol_info(vol); + return -EINVAL; +} + +/** + * check_scanning_info - check that scanning information. + * @ubi: UBI device description object + * @si: scanning information + * + * Even though we protect on-flash data by CRC checksums, we still don't trust + * the media. This function ensures that scanning information is consistent to + * the information read from the volume table. Returns zero if the scanning + * information is OK and %-EINVAL if it is not. + */ +static int check_scanning_info(const struct ubi_device *ubi, + struct ubi_scan_info *si) +{ + int err, i; + struct ubi_scan_volume *sv; + struct ubi_volume *vol; + + if (si->vols_found > UBI_INT_VOL_COUNT + ubi->vtbl_slots) { + ubi_err("scanning found %d volumes, maximum is %d + %d", + si->vols_found, UBI_INT_VOL_COUNT, ubi->vtbl_slots); + return -EINVAL; + } + + if (si->highest_vol_id >= ubi->vtbl_slots + UBI_INT_VOL_COUNT && + si->highest_vol_id < UBI_INTERNAL_VOL_START) { + ubi_err("too large volume ID %d found by scanning", + si->highest_vol_id); + return -EINVAL; + } + + for (i = 0; i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) { + cond_resched(); + + sv = ubi_scan_find_sv(si, i); + vol = ubi->volumes[i]; + if (!vol) { + if (sv) + ubi_scan_rm_volume(si, sv); + continue; + } + + if (vol->reserved_pebs == 0) { + ubi_assert(i < ubi->vtbl_slots); + + if (!sv) + continue; + + /* + * During scanning we found a volume which does not + * exist according to the information in the volume + * table. This must have happened due to an unclean + * reboot while the volume was being removed. Discard + * these eraseblocks. + */ + ubi_msg("finish volume %d removal", sv->vol_id); + ubi_scan_rm_volume(si, sv); + } else if (sv) { + err = check_sv(vol, sv); + if (err) + return err; + } + } + + return 0; +} + +/** + * ubi_read_volume_table - read volume table. + * information. + * @ubi: UBI device description object + * @si: scanning information + * + * This function reads volume table, checks it, recover from errors if needed, + * or creates it if needed. Returns zero in case of success and a negative + * error code in case of failure. + */ +int ubi_read_volume_table(struct ubi_device *ubi, struct ubi_scan_info *si) +{ + int i, err; + struct ubi_scan_volume *sv; + + empty_vtbl_record.crc = cpu_to_be32(0xf116c36b); + + /* + * The number of supported volumes is limited by the eraseblock size + * and by the UBI_MAX_VOLUMES constant. + */ + ubi->vtbl_slots = ubi->leb_size / UBI_VTBL_RECORD_SIZE; + if (ubi->vtbl_slots > UBI_MAX_VOLUMES) + ubi->vtbl_slots = UBI_MAX_VOLUMES; + + ubi->vtbl_size = ubi->vtbl_slots * UBI_VTBL_RECORD_SIZE; + ubi->vtbl_size = ALIGN(ubi->vtbl_size, ubi->min_io_size); + + sv = ubi_scan_find_sv(si, UBI_LAYOUT_VOLUME_ID); + if (!sv) { + /* + * No logical eraseblocks belonging to the layout volume were + * found. This could mean that the flash is just empty. In + * this case we create empty layout volume. + * + * But if flash is not empty this must be a corruption or the + * MTD device just contains garbage. + */ + if (si->is_empty) { + ubi->vtbl = create_empty_lvol(ubi, si); + if (IS_ERR(ubi->vtbl)) + return PTR_ERR(ubi->vtbl); + } else { + ubi_err("the layout volume was not found"); + return -EINVAL; + } + } else { + if (sv->leb_count > UBI_LAYOUT_VOLUME_EBS) { + /* This must not happen with proper UBI images */ + dbg_err("too many LEBs (%d) in layout volume", + sv->leb_count); + return -EINVAL; + } + + ubi->vtbl = process_lvol(ubi, si, sv); + if (IS_ERR(ubi->vtbl)) + return PTR_ERR(ubi->vtbl); + } + + ubi->avail_pebs = ubi->good_peb_count; + + /* + * The layout volume is OK, initialize the corresponding in-RAM data + * structures. + */ + err = init_volumes(ubi, si, ubi->vtbl); + if (err) + goto out_free; + + /* + * Get sure that the scanning information is consistent to the + * information stored in the volume table. + */ + err = check_scanning_info(ubi, si); + if (err) + goto out_free; + + return 0; + +out_free: + vfree(ubi->vtbl); + for (i = 0; i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) + if (ubi->volumes[i]) { + kfree(ubi->volumes[i]); + ubi->volumes[i] = NULL; + } + return err; +} + +#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID + +/** + * paranoid_vtbl_check - check volume table. + * @ubi: UBI device description object + */ +static void paranoid_vtbl_check(const struct ubi_device *ubi) +{ + if (vtbl_check(ubi, ubi->vtbl)) { + ubi_err("paranoid check failed"); + BUG(); + } +} + +#endif /* CONFIG_MTD_UBI_DEBUG_PARANOID */