/* * Copyright (C) 2014 Gabor Juhos <juhosg@openwrt.org> * * 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 <asm/unaligned.h> #include "mtdsplit.h" #define LZMA_NR_PARTS 2 #define LZMA_PROPERTIES_SIZE 5 struct lzma_header { u8 props[LZMA_PROPERTIES_SIZE]; u8 size_low[4]; u8 size_high[4]; }; static int mtdsplit_parse_lzma(struct mtd_info *master, struct mtd_partition **pparts, struct mtd_part_parser_data *data) { struct lzma_header hdr; size_t hdr_len, retlen; size_t rootfs_offset; u32 t; struct mtd_partition *parts; int err; hdr_len = sizeof(hdr); err = mtd_read(master, 0, hdr_len, &retlen, (void *) &hdr); if (err) return err; if (retlen != hdr_len) return -EIO; /* verify LZMA properties */ if (hdr.props[0] >= (9 * 5 * 5)) return -EINVAL; t = get_unaligned_le32(&hdr.props[1]); if (!is_power_of_2(t)) return -EINVAL; t = get_unaligned_le32(&hdr.size_high); if (t) return -EINVAL; err = mtd_find_rootfs_from(master, master->erasesize, master->size, &rootfs_offset); if (err) return err; parts = kzalloc(LZMA_NR_PARTS * sizeof(*parts), GFP_KERNEL); if (!parts) return -ENOMEM; parts[0].name = KERNEL_PART_NAME; parts[0].offset = 0; parts[0].size = rootfs_offset; parts[1].name = ROOTFS_PART_NAME; parts[1].offset = rootfs_offset; parts[1].size = master->size - rootfs_offset; *pparts = parts; return LZMA_NR_PARTS; } static struct mtd_part_parser mtdsplit_lzma_parser = { .owner = THIS_MODULE, .name = "lzma-fw", .parse_fn = mtdsplit_parse_lzma, .type = MTD_PARSER_TYPE_FIRMWARE, }; static int __init mtdsplit_lzma_init(void) { register_mtd_parser(&mtdsplit_lzma_parser); return 0; } subsys_initcall(mtdsplit_lzma_init);