aboutsummaryrefslogtreecommitdiffstats
path: root/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_brnimage.c
diff options
context:
space:
mode:
Diffstat (limited to 'target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_brnimage.c')
-rw-r--r--target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_brnimage.c104
1 files changed, 104 insertions, 0 deletions
diff --git a/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_brnimage.c b/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_brnimage.c
new file mode 100644
index 0000000000..7ddd69b7b7
--- /dev/null
+++ b/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_brnimage.c
@@ -0,0 +1,104 @@
+/*
+ * 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);
+ 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);