| From: Daniel Golle <daniel@makrotopia.org> |
| Subject: ubi: auto-create ubiblock device for rootfs |
| |
| Signed-off-by: Daniel Golle <daniel@makrotopia.org> |
| --- |
| drivers/mtd/ubi/block.c | 42 ++++++++++++++++++++++++++++++++++++++++++ |
| 1 file changed, 42 insertions(+) |
| |
| --- a/drivers/mtd/ubi/block.c |
| +++ b/drivers/mtd/ubi/block.c |
| @@ -652,6 +652,44 @@ static void __init ubiblock_create_from_ |
| } |
| } |
| |
| +#define UBIFS_NODE_MAGIC 0x06101831 |
| +static inline int ubi_vol_is_ubifs(struct ubi_volume_desc *desc) |
| +{ |
| + int ret; |
| + uint32_t magic_of, magic; |
| + ret = ubi_read(desc, 0, (char *)&magic_of, 0, 4); |
| + if (ret) |
| + return 0; |
| + magic = le32_to_cpu(magic_of); |
| + return magic == UBIFS_NODE_MAGIC; |
| +} |
| + |
| +static void __init ubiblock_create_auto_rootfs(void) |
| +{ |
| + int ubi_num, ret, is_ubifs; |
| + struct ubi_volume_desc *desc; |
| + struct ubi_volume_info vi; |
| + |
| + for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++) { |
| + desc = ubi_open_volume_nm(ubi_num, "rootfs", UBI_READONLY); |
| + if (IS_ERR(desc)) |
| + continue; |
| + |
| + ubi_get_volume_info(desc, &vi); |
| + is_ubifs = ubi_vol_is_ubifs(desc); |
| + ubi_close_volume(desc); |
| + if (is_ubifs) |
| + break; |
| + |
| + ret = ubiblock_create(&vi); |
| + if (ret) |
| + pr_err("UBI error: block: can't add '%s' volume, err=%d\n", |
| + vi.name, ret); |
| + /* always break if we get here */ |
| + break; |
| + } |
| +} |
| + |
| static void ubiblock_remove_all(void) |
| { |
| struct ubiblock *next; |
| @@ -684,6 +722,10 @@ int __init ubiblock_init(void) |
| */ |
| ubiblock_create_from_param(); |
| |
| + /* auto-attach "rootfs" volume if existing and non-ubifs */ |
| + if (IS_ENABLED(CONFIG_MTD_ROOTFS_ROOT_DEV)) |
| + ubiblock_create_auto_rootfs(); |
| + |
| /* |
| * Block devices are only created upon user requests, so we ignore |
| * existing volumes. |