linux-imx

/*

 * rfd_ftl.c -- resident flash disk (flash translation layer)

 *

 * Copyright © 2005  Sean Young <sean@mess.org>

 *

 * This type of flash translation layer (FTL) is used by the Embedded BIOS

 * by General Software. It is known as the Resident Flash Disk (RFD), see:

 *

 *  http://www.gensw.com/pages/prod/bios/rfd.htm

 *

 * based on ftl.c

 */

​

#include <linux/hdreg.h>

#include <linux/init.h>

#include <linux/mtd/blktrans.h>

#include <linux/mtd/mtd.h>

#include <linux/vmalloc.h>

#include <linux/slab.h>

#include <linux/jiffies.h>

#include <linux/module.h>

​

#include <asm/types.h>

​

static int block_size = 0;

module_param(block_size, int, 0);

MODULE_PARM_DESC(block_size, "Block size to use by RFD, defaults to erase unit size");

​

#define PREFIX "rfd_ftl: "

​

/* This major has been assigned by device@lanana.org */

#ifndef RFD_FTL_MAJOR

#define RFD_FTL_MAJOR       256

#endif

​

/* Maximum number of partitions in an FTL region */

#define PART_BITS       4

​

/* An erase unit should start with this value */

#define RFD_MAGIC       0x9193

​

/* the second value is 0xffff or 0xffc8; function unknown */

​

/* the third value is always 0xffff, ignored */

​

/* next is an array of mapping for each corresponding sector */

#define HEADER_MAP_OFFSET   3

#define SECTOR_DELETED      0x0000

#define SECTOR_ZERO     0xfffe

#define SECTOR_FREE     0xffff

​

#define SECTOR_SIZE     512

​

#define SECTORS_PER_TRACK   63

​

struct block {

    enum {

        BLOCK_OK,

        BLOCK_ERASING,

        BLOCK_ERASED,

        BLOCK_UNUSED,

        BLOCK_FAILED

    } state;