104 lines
2.5 KiB
C
104 lines
2.5 KiB
C
/*
|
|
* Copyright (C) 2012 John Crispin <blogic@openwrt.org>
|
|
* Copyright (C) 2015 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms of the GNU General Public License version 2 as published
|
|
* by the Free Software Foundation.
|
|
*
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/init.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/mtd/mtd.h>
|
|
#include <linux/mtd/partitions.h>
|
|
#include <linux/byteorder/generic.h>
|
|
|
|
#include "mtdsplit.h"
|
|
|
|
#define BRNIMAGE_NR_PARTS 2
|
|
|
|
#define BRNIMAGE_ALIGN_BYTES 0x400
|
|
#define BRNIMAGE_FOOTER_SIZE 12
|
|
|
|
#define BRNIMAGE_MIN_OVERHEAD (BRNIMAGE_FOOTER_SIZE)
|
|
#define BRNIMAGE_MAX_OVERHEAD (BRNIMAGE_ALIGN_BYTES + BRNIMAGE_FOOTER_SIZE)
|
|
|
|
static int mtdsplit_parse_brnimage(struct mtd_info *master,
|
|
const struct mtd_partition **pparts,
|
|
struct mtd_part_parser_data *data)
|
|
{
|
|
struct mtd_partition *parts;
|
|
uint32_t buf;
|
|
unsigned long rootfs_offset, rootfs_size, kernel_size;
|
|
size_t len;
|
|
int ret = 0;
|
|
|
|
for (rootfs_offset = 0; rootfs_offset < master->size;
|
|
rootfs_offset += BRNIMAGE_ALIGN_BYTES) {
|
|
ret = mtd_check_rootfs_magic(master, rootfs_offset, NULL);
|
|
if (!ret)
|
|
break;
|
|
}
|
|
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (rootfs_offset >= master->size)
|
|
return -EINVAL;
|
|
|
|
ret = mtd_read(master, rootfs_offset - BRNIMAGE_FOOTER_SIZE, 4, &len,
|
|
(void *)&buf);
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (len != 4)
|
|
return -EIO;
|
|
|
|
kernel_size = le32_to_cpu(buf);
|
|
|
|
if (kernel_size > (rootfs_offset - BRNIMAGE_MIN_OVERHEAD))
|
|
return -EINVAL;
|
|
|
|
if (kernel_size < (rootfs_offset - BRNIMAGE_MAX_OVERHEAD))
|
|
return -EINVAL;
|
|
|
|
/*
|
|
* The footer must be untouched as it contains the checksum of the
|
|
* original brnImage (kernel + squashfs)!
|
|
*/
|
|
rootfs_size = master->size - rootfs_offset - BRNIMAGE_FOOTER_SIZE;
|
|
|
|
parts = kzalloc(BRNIMAGE_NR_PARTS * sizeof(*parts), GFP_KERNEL);
|
|
if (!parts)
|
|
return -ENOMEM;
|
|
|
|
parts[0].name = KERNEL_PART_NAME;
|
|
parts[0].offset = 0;
|
|
parts[0].size = kernel_size;
|
|
|
|
parts[1].name = ROOTFS_PART_NAME;
|
|
parts[1].offset = rootfs_offset;
|
|
parts[1].size = rootfs_size;
|
|
|
|
*pparts = parts;
|
|
return BRNIMAGE_NR_PARTS;
|
|
}
|
|
|
|
static struct mtd_part_parser mtdsplit_brnimage_parser = {
|
|
.owner = THIS_MODULE,
|
|
.name = "brnimage-fw",
|
|
.parse_fn = mtdsplit_parse_brnimage,
|
|
.type = MTD_PARSER_TYPE_FIRMWARE,
|
|
};
|
|
|
|
static int __init mtdsplit_brnimage_init(void)
|
|
{
|
|
register_mtd_parser(&mtdsplit_brnimage_parser);
|
|
|
|
return 0;
|
|
}
|
|
|
|
subsys_initcall(mtdsplit_brnimage_init);
|