• Christian Gmeiner's avatar
    fs: make it possible to read the filesystem UUID · 59e890ef
    Christian Gmeiner authored
    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.
    
    changes rfc -> v1:
     - make the environment variable an option parameter. If not
       given, the UUID is printed out. If given, it is stored in the env
       variable.
     - corrected typos
     - return error codes
    
    changes v1 -> v2:
     - fix return code of do_fs_uuid(..)
     - document do_fs_uuid(..)
     - implement fs_uuid_unsuported(..) be more consistent with the
       way other optional functionality works
    
    changes v2 -> v3:
     - change ext4fs_uuid(..) to make use of #if .. #else .. #endif
       construct to get rid of unreachable code
    
    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: default avatarChristian Gmeiner <christian.gmeiner@gmail.com>
    Acked-by: default avatarStephen Warren <swarren@nvidia.com>
    59e890ef
cmd_fs_uuid.c 593 Bytes