ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit.c b/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit.c
new file mode 100644
index 0000000..b2e51dc
--- /dev/null
+++ b/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit.c
@@ -0,0 +1,130 @@
+/*
+ * Copyright (C) 2009-2013 Felix Fietkau <nbd@nbd.name>
+ * Copyright (C) 2009-2013 Gabor Juhos <juhosg@openwrt.org>
+ * Copyright (C) 2012 Jonas Gorski <jogo@openwrt.org>
+ * Copyright (C) 2013 Hauke Mehrtens <hauke@hauke-m.de>
+ *
+ * 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.
+ *
+ */
+
+#define pr_fmt(fmt) "mtdsplit: " fmt
+
+#include <linux/export.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/magic.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/byteorder/generic.h>
+
+#include "mtdsplit.h"
+
+#define UBI_EC_MAGIC 0x55424923 /* UBI# */
+
+struct squashfs_super_block {
+ __le32 s_magic;
+ __le32 pad0[9];
+ __le64 bytes_used;
+};
+
+int mtd_get_squashfs_len(struct mtd_info *master,
+ size_t offset,
+ size_t *squashfs_len)
+{
+ struct squashfs_super_block sb;
+ size_t retlen;
+ int err;
+
+ err = mtd_read(master, offset, sizeof(sb), &retlen, (void *)&sb);
+ if (err || (retlen != sizeof(sb))) {
+ pr_alert("error occured while reading from \"%s\"\n",
+ master->name);
+ return -EIO;
+ }
+
+ if (le32_to_cpu(sb.s_magic) != SQUASHFS_MAGIC) {
+ pr_alert("no squashfs found in \"%s\"\n", master->name);
+ return -EINVAL;
+ }
+
+ retlen = le64_to_cpu(sb.bytes_used);
+ if (retlen <= 0) {
+ pr_alert("squashfs is empty in \"%s\"\n", master->name);
+ return -ENODEV;
+ }
+
+ if (offset + retlen > master->size) {
+ pr_alert("squashfs has invalid size in \"%s\"\n",
+ master->name);
+ return -EINVAL;
+ }
+
+ *squashfs_len = retlen;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mtd_get_squashfs_len);
+
+static ssize_t mtd_next_eb(struct mtd_info *mtd, size_t offset)
+{
+ return mtd_rounddown_to_eb(offset, mtd) + mtd->erasesize;
+}
+
+int mtd_check_rootfs_magic(struct mtd_info *mtd, size_t offset,
+ enum mtdsplit_part_type *type)
+{
+ u32 magic;
+ size_t retlen;
+ int ret;
+
+ ret = mtd_read(mtd, offset, sizeof(magic), &retlen,
+ (unsigned char *) &magic);
+ if (ret)
+ return ret;
+
+ if (retlen != sizeof(magic))
+ return -EIO;
+
+ if (le32_to_cpu(magic) == SQUASHFS_MAGIC) {
+ if (type)
+ *type = MTDSPLIT_PART_TYPE_SQUASHFS;
+ return 0;
+ } else if (magic == 0x19852003) {
+ if (type)
+ *type = MTDSPLIT_PART_TYPE_JFFS2;
+ return 0;
+ } else if (be32_to_cpu(magic) == UBI_EC_MAGIC) {
+ if (type)
+ *type = MTDSPLIT_PART_TYPE_UBI;
+ return 0;
+ }
+
+ return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(mtd_check_rootfs_magic);
+
+int mtd_find_rootfs_from(struct mtd_info *mtd,
+ size_t from,
+ size_t limit,
+ size_t *ret_offset,
+ enum mtdsplit_part_type *type)
+{
+ size_t offset;
+ int err;
+
+ for (offset = from; offset < limit;
+ offset = mtd_next_eb(mtd, offset)) {
+ err = mtd_check_rootfs_magic(mtd, offset, type);
+ if (err)
+ continue;
+
+ *ret_offset = offset;
+ return 0;
+ }
+
+ return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(mtd_find_rootfs_from);
+