Some filesystems have a UUID stored in its superblock. To allow using root=UUID=... for the kernel command line we need a way to read-out the filesystem UUID.
Hit any key to stop autoboot: 0 => fsuuid fsuuid - Look up a filesystem UUID
Usage: fsuuid <interface> <dev>:<part> - print filesystem UUID fsuuid <interface> <dev>:<part> <varname> - set environment variable to filesystem UUID
=> fsuuid mmc 0:1 d9f9fc05-45ae-4a36-a616-fccce0e4f887 => fsuuid mmc 0:2 eb3db83c-7b28-499f-95ce-9e0bb21cda81 => fsuuid mmc 0:1 uuid1 => fsuuid mmc 0:2 uuid2 => printenv uuid1 uuid1=d9f9fc05-45ae-4a36-a616-fccce0e4f887 => printenv uuid2 uuid2=eb3db83c-7b28-499f-95ce-9e0bb21cda81 =>
Signed-off-by: Christian Gmeiner christian.gmeiner@gmail.com --- README | 1 + common/Makefile | 1 + fs/ext4/ext4fs.c | 15 +++++++++++++++ fs/fs.c | 39 +++++++++++++++++++++++++++++++++++++++ include/ext4fs.h | 1 + include/fs.h | 2 ++ 6 files changed, 59 insertions(+)
diff --git a/README b/README index 7b5538e..53b84a6 100644 --- a/README +++ b/README @@ -989,6 +989,7 @@ The following options need to be configured: CONFIG_CMD_EXT4 * ext4 command support CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls) that work for multiple fs types + CONFIG_CMD_FS_UUID * Look up a filesystem UUID CONFIG_CMD_SAVEENV saveenv CONFIG_CMD_FDC * Floppy Disk Support CONFIG_CMD_FAT * FAT command support diff --git a/common/Makefile b/common/Makefile index 6cc4de8..508a0b2 100644 --- a/common/Makefile +++ b/common/Makefile @@ -188,6 +188,7 @@ obj-y += usb.o usb_hub.o obj-$(CONFIG_USB_STORAGE) += usb_storage.o endif obj-$(CONFIG_CMD_FASTBOOT) += cmd_fastboot.o +obj-$(CONFIG_CMD_FS_UUID) += cmd_fs_uuid.o
obj-$(CONFIG_CMD_USB_MASS_STORAGE) += cmd_usb_mass_storage.o obj-$(CONFIG_CMD_THOR_DOWNLOAD) += cmd_thordown.o diff --git a/fs/ext4/ext4fs.c b/fs/ext4/ext4fs.c index cbdc220..61b6dc2 100644 --- a/fs/ext4/ext4fs.c +++ b/fs/ext4/ext4fs.c @@ -187,6 +187,21 @@ int ext4fs_size(const char *filename) return ext4fs_open(filename); }
+int ext4fs_uuid(char *uuid_str) +{ + if (ext4fs_root == NULL) + return -1; + +#ifdef CONFIG_LIB_UUID + uuid_bin_to_str((unsigned char *)ext4fs_root->sblock.unique_id, + uuid_str, UUID_STR_FORMAT_STD); + + return 0; +#endif + + return -ENOSYS; +} + int ext4fs_read(char *buf, unsigned len) { if (ext4fs_root == NULL || ext4fs_file == NULL) diff --git a/fs/fs.c b/fs/fs.c index dd680f3..492d8b1 100644 --- a/fs/fs.c +++ b/fs/fs.c @@ -15,6 +15,7 @@ */
#include <config.h> +#include <errno.h> #include <common.h> #include <part.h> #include <ext4fs.h> @@ -86,6 +87,7 @@ struct fstype_info { int (*read)(const char *filename, void *buf, int offset, int len); int (*write)(const char *filename, void *buf, int offset, int len); void (*close)(void); + int (*uuid)(char *uuid_str); };
static struct fstype_info fstypes[] = { @@ -113,6 +115,7 @@ static struct fstype_info fstypes[] = { .size = ext4fs_size, .read = ext4_read_file, .write = fs_write_unsupported, + .uuid = ext4fs_uuid, }, #endif #ifdef CONFIG_SANDBOX @@ -206,6 +209,17 @@ static void fs_close(void) fs_type = FS_TYPE_ANY; }
+int fs_uuid(char *uuid_str) +{ + struct fstype_info *info = fs_get_info(fs_type); + int ret = -ENOSYS; + + if (info->uuid) + ret = info->uuid(uuid_str); + + return ret; +} + int fs_ls(const char *dirname) { int ret; @@ -443,3 +457,28 @@ int do_save(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[],
return 0; } + +int do_fs_uuid(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[], + int fstype) +{ + int ret; + char uuid[37]; + memset(uuid, 0, sizeof(uuid)); + + if (argc < 3 || argc > 4) + return CMD_RET_USAGE; + + if (fs_set_blk_dev(argv[1], argv[2], fstype)) + return 1; + + ret = fs_uuid(uuid); + if (ret) + return ret; + + if (argc == 4) + setenv(argv[3], uuid); + else + printf("%s\n", uuid); + + return 0; +} diff --git a/include/ext4fs.h b/include/ext4fs.h index 6c419f3..19816de 100644 --- a/include/ext4fs.h +++ b/include/ext4fs.h @@ -137,6 +137,7 @@ void ext4fs_reinit_global(void); int ext4fs_ls(const char *dirname); int ext4fs_exists(const char *filename); int ext4fs_size(const char *filename); +int ext4fs_uuid(char *uuid_str); void ext4fs_free_node(struct ext2fs_node *node, struct ext2fs_node *currroot); int ext4fs_devread(lbaint_t sector, int byte_offset, int byte_len, char *buf); void ext4fs_set_blk_dev(block_dev_desc_t *rbdd, disk_partition_t *info); diff --git a/include/fs.h b/include/fs.h index 06a45f2..41082b3 100644 --- a/include/fs.h +++ b/include/fs.h @@ -92,5 +92,7 @@ int file_exists(const char *dev_type, const char *dev_part, const char *file, int fstype); int do_save(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[], int fstype); +int do_fs_uuid(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[], + int fstype);
#endif /* _FS_H */