ubi-user.h

Go to the documentation of this file.

/*
 * Copyright © 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)
 */

#ifndef __UBI_USER_H__
#define __UBI_USER_H__

#include <linux/types.h>

/*
 * UBI device creation (the same as MTD device attachment)
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 * MTD devices may be attached using %UBI_IOCATT ioctl command of the UBI
 * control device. The caller has to properly fill and pass
 * &struct ubi_attach_req object - UBI will attach the MTD device specified in
 * the request and return the newly created UBI device number as the ioctl
 * return value.
 *
 * UBI device deletion (the same as MTD device detachment)
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 * An UBI device maybe deleted with %UBI_IOCDET ioctl command of the UBI
 * control device.
 *
 * UBI volume creation
 * ~~~~~~~~~~~~~~~~~~~
 *
 * UBI volumes are created via the %UBI_IOCMKVOL ioctl command of UBI character
 * device. A &struct ubi_mkvol_req object has to be properly filled and a
 * pointer to it has to be passed to the ioctl.
 *
 * UBI volume deletion
 * ~~~~~~~~~~~~~~~~~~~
 *
 * To delete a volume, the %UBI_IOCRMVOL ioctl command of the UBI character
 * device should be used. A pointer to the 32-bit volume ID hast to be passed
 * to the ioctl.
 *
 * UBI volume re-size
 * ~~~~~~~~~~~~~~~~~~
 *
 * To re-size a volume, the %UBI_IOCRSVOL ioctl command of the UBI character
 * device should be used. A &struct ubi_rsvol_req object has to be properly
 * filled and a pointer to it has to be passed to the ioctl.
 *
 * UBI volumes re-name
 * ~~~~~~~~~~~~~~~~~~~
 *
 * To re-name several volumes atomically at one go, the %UBI_IOCRNVOL command
 * of the UBI character device should be used. A &struct ubi_rnvol_req object
 * has to be properly filled and a pointer to it has to be passed to the ioctl.
 *
 * UBI volume update
 * ~~~~~~~~~~~~~~~~~
 *
 * Volume update should be done via the %UBI_IOCVOLUP ioctl command of the
 * corresponding UBI volume character device. A pointer to a 64-bit update
 * size should be passed to the ioctl. After this, UBI expects user to write
 * this number of bytes to the volume character device. The update is finished
 * when the claimed number of bytes is passed. So, the volume update sequence
 * is something like:
 *
 * fd = open("/dev/my_volume");
 * ioctl(fd, UBI_IOCVOLUP, &image_size);
 * write(fd, buf, image_size);
 * close(fd);
 *
 * Logical eraseblock erase
 * ~~~~~~~~~~~~~~~~~~~~~~~~
 *
 * To erase a logical eraseblock, the %UBI_IOCEBER ioctl command of the
 * corresponding UBI volume character device should be used. This command
 * unmaps the requested logical eraseblock, makes sure the corresponding
 * physical eraseblock is successfully erased, and returns.
 *
 * Atomic logical eraseblock change
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 * Atomic logical eraseblock change operation is called using the %UBI_IOCEBCH
 * ioctl command of the corresponding UBI volume character device. A pointer to
 * a &struct ubi_leb_change_req object has to be passed to the ioctl. Then the
 * user is expected to write the requested amount of bytes (similarly to what
 * should be done in case of the "volume update" ioctl).
 *
 * Logical eraseblock map
 * ~~~~~~~~~~~~~~~~~~~~~
 *
 * To map a logical eraseblock to a physical eraseblock, the %UBI_IOCEBMAP
 * ioctl command should be used. A pointer to a &struct ubi_map_req object is
 * expected to be passed. The ioctl maps the requested logical eraseblock to
 * a physical eraseblock and returns.  Only non-mapped logical eraseblocks can
 * be mapped. If the logical eraseblock specified in the request is already
 * mapped to a physical eraseblock, the ioctl fails and returns error.
 *
 * Logical eraseblock unmap
 * ~~~~~~~~~~~~~~~~~~~~~~~~
 *
 * To unmap a logical eraseblock to a physical eraseblock, the %UBI_IOCEBUNMAP
 * ioctl command should be used. The ioctl unmaps the logical eraseblocks,
 * schedules corresponding physical eraseblock for erasure, and returns. Unlike
 * the "LEB erase" command, it does not wait for the physical eraseblock being
 * erased. Note, the side effect of this is that if an unclean reboot happens
 * after the unmap ioctl returns, you may find the LEB mapped again to the same
 * physical eraseblock after the UBI is run again.
 *
 * Check if logical eraseblock is mapped
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 * To check if a logical eraseblock is mapped to a physical eraseblock, the
 * %UBI_IOCEBISMAP ioctl command should be used. It returns %0 if the LEB is
 * not mapped, and %1 if it is mapped.
 *
 * Set an UBI volume property
 * ~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 * To set an UBI volume property the %UBI_IOCSETPROP ioctl command should be
 * used. A pointer to a &struct ubi_set_vol_prop_req object is expected to be
 * passed. The object describes which property should be set, and to which value
 * it should be set.
 */

/*
 * When a new UBI volume or UBI device is created, users may either specify the
 * volume/device number they want to create or to let UBI automatically assign
 * the number using these constants.
 */
#define UBI_VOL_NUM_AUTO (-1)
#define UBI_DEV_NUM_AUTO (-1)

/* Maximum volume name length */
#define UBI_MAX_VOLUME_NAME 127

/* ioctl commands of UBI character devices */

#define UBI_IOC_MAGIC 'o'

/* Create an UBI volume */
#define UBI_IOCMKVOL _IOW(UBI_IOC_MAGIC, 0, struct ubi_mkvol_req)
/* Remove an UBI volume */
#define UBI_IOCRMVOL _IOW(UBI_IOC_MAGIC, 1, __s32)
/* Re-size an UBI volume */
#define UBI_IOCRSVOL _IOW(UBI_IOC_MAGIC, 2, struct ubi_rsvol_req)
/* Re-name volumes */
#define UBI_IOCRNVOL _IOW(UBI_IOC_MAGIC, 3, struct ubi_rnvol_req)

/* ioctl commands of the UBI control character device */

#define UBI_CTRL_IOC_MAGIC 'o'

/* Attach an MTD device */
#define UBI_IOCATT _IOW(UBI_CTRL_IOC_MAGIC, 64, struct ubi_attach_req)
/* Detach an MTD device */
#define UBI_IOCDET _IOW(UBI_CTRL_IOC_MAGIC, 65, __s32)

/* ioctl commands of UBI volume character devices */

#define UBI_VOL_IOC_MAGIC 'O'

/* Start UBI volume update */
#define UBI_IOCVOLUP _IOW(UBI_VOL_IOC_MAGIC, 0, __s64)
/* LEB erasure command, used for debugging, disabled by default */
#define UBI_IOCEBER _IOW(UBI_VOL_IOC_MAGIC, 1, __s32)
/* Atomic LEB change command */
#define UBI_IOCEBCH _IOW(UBI_VOL_IOC_MAGIC, 2, __s32)
/* Map LEB command */
#define UBI_IOCEBMAP _IOW(UBI_VOL_IOC_MAGIC, 3, struct ubi_map_req)
/* Unmap LEB command */
#define UBI_IOCEBUNMAP _IOW(UBI_VOL_IOC_MAGIC, 4, __s32)
/* Check if LEB is mapped command */
#define UBI_IOCEBISMAP _IOR(UBI_VOL_IOC_MAGIC, 5, __s32)
/* Set an UBI volume property */
#define UBI_IOCSETVOLPROP _IOW(UBI_VOL_IOC_MAGIC, 6, \
                   struct ubi_set_vol_prop_req)

/* Maximum MTD device name length supported by UBI */
#define MAX_UBI_MTD_NAME_LEN 127

/* Maximum amount of UBI volumes that can be re-named at one go */
#define UBI_MAX_RNVOL 32

/*
 * UBI volume type constants.
 *
 * @UBI_DYNAMIC_VOLUME: dynamic volume
 * @UBI_STATIC_VOLUME:  static volume
 */
enum {
    UBI_DYNAMIC_VOLUME = 3,
    UBI_STATIC_VOLUME  = 4,
};

/*
 * UBI set volume property ioctl constants.
 *
 * @UBI_VOL_PROP_DIRECT_WRITE: allow (any non-zero value) or disallow (value 0)
 *                             user to directly write and erase individual
 *                             eraseblocks on dynamic volumes
 */
enum {
    UBI_VOL_PROP_DIRECT_WRITE = 1,
};

struct ubi_attach_req {
    __s32 ubi_num;
    __s32 mtd_num;
    __s32 vid_hdr_offset;
    __s16 max_beb_per1024;
    __s8 padding[10];
};

struct ubi_mkvol_req {
    __s32 vol_id;
    __s32 alignment;
    __s64 bytes;
    __s8 vol_type;
    __s8 padding1;
    __s16 name_len;
    __s8 padding2[4];
    char name[UBI_MAX_VOLUME_NAME + 1];
} __packed;

struct ubi_rsvol_req {
    __s64 bytes;
    __s32 vol_id;
} __packed;

struct ubi_rnvol_req {
    __s32 count;
    __s8 padding1[12];
    struct {
        __s32 vol_id;
        __s16 name_len;
        __s8  padding2[2];
        char    name[UBI_MAX_VOLUME_NAME + 1];
    } ents[UBI_MAX_RNVOL];
} __packed;

struct ubi_leb_change_req {
    __s32 lnum;
    __s32 bytes;
    __s8  dtype; /* obsolete, do not use! */
    __s8  padding[7];
} __packed;

struct ubi_map_req {
    __s32 lnum;
    __s8  dtype; /* obsolete, do not use! */
    __s8  padding[3];
} __packed;


struct ubi_set_vol_prop_req {
    __u8  property;
    __u8  padding[7];
    __u64 value;
}  __packed;

#endif /* __UBI_USER_H__ */