openwrtv4/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_brnimage.c
Rafał Miłecki e1491b341b kernel: mtdsplit: modify rootfs helpers to provide partition type
Our mtdsplit parsers may want to create partition with name choice based
on partition file system (e.g. SquashFS vs. JFFS2). This patch allows
passing extra argument pointing to variable that will be set properly.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>

SVN-Revision: 48598
2016-02-01 12:41:41 +00:00

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,
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;
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);