/*
 * 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 B. Bityutskiy
 */

#ifndef __UBI_USER_H__
#define __UBI_USER_H__

#ifndef __KERNEL__
#define __user
#endif

/*
 * When a new volume is created, users may either specify the volume number they
 * want to create or to let UBI automatically assign a volume number using this
 * constant.
 */
#define UBI_VOL_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, int32_t)
/* Re-size an UBI volume */
#define UBI_IOCRSVOL _IOW(UBI_IOC_MAGIC, 2, struct ubi_rsvol_req)

/*
 * 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, int64_t)
/* An eraseblock erasure command, used for debugging, disabled by dafault */
#define UBI_IOCEBER _IOW(UBI_VOL_IOC_MAGIC, 0, int32_t)

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

/**
 * struct ubi_mkvol_req - volume description data structure used in
 * volume creation requests.
 *
 * @vol_id: volume number
 * @alignment: volume alignment
 * @bytes: volume size in bytes
 * @vol_type: volume type (%UBI_DYNAMIC_VOLUME or %UBI_STATIC_VOLUME)
 * @padding: reserved for future, not used
 * @name_len: volume name length
 * @name: volume name
 *
 * This structure is used by userspace programs when creating new volumes. The
 * @used_bytes field is only necessary when creating static volumes.
 *
 * The @alignment field specifies the required alignment of the volume logical
 * eraseblock. This means, that the size of logical eraseblocks will be aligned
 * to this number, i.e.,
 * 	(UBI device logical eraseblock size) mod (@alignment) = 0.
 *
 * To put it differently, the logical eraseblock of this volume may be slightly
 * shortened in order to make it properly aligned. The alignment has to be
 * multiple of the flash minimal input/output unit, or %1 to utilize the entire
 * available space of logical eraseblocks.
 *
 * The @alignment field may be useful, for example, when one wants to maintain
 * a block device on top of an UBI volume. In this case, it is desirable to fit
 * an integer number of blocks in logical eraseblocks of this UBI volume. With
 * alignment it is possible to update this volume using plane UBI volume image
 * BLOBs, without caring about how to properly write them.
 */
struct ubi_mkvol_req {
	int32_t vol_id;
	int32_t alignment;
	int64_t bytes;
	int8_t vol_type;
	int8_t padding[9];
	int16_t name_len;
	__user const char *name;
} __attribute__ ((packed));

/**
 * struct ubi_rsvol_req - a data structure used in volume re-size requests.
 *
 * @vol_id: ID of the volume to re-size
 * @bytes: new size of the volume in bytes
 *
 * Re-sizing is possible for both dynamic and static volumes. But while dynamic
 * volumes may be re-sized arbitrarily, static volumes cannot be made to be
 * smaller then the number of bytes they bear. To arbitrarily shrink a static
 * volume, it must be wiped out first (by means of volume update operation with
 * zero number of bytes).
 */
struct ubi_rsvol_req {
	int64_t bytes;
	int32_t vol_id;
} __attribute__ ((packed));

#endif /* __UBI_USER_H__ */