Unmounting by filesystem ID

[David O'Brien]

On Sat, Jun 28, 2003 at 10:54:04PM +0100, Ian Dowse wrote:
> The patch below adds a new mount flag MNT_BYFSID that can be used
> to unmount a filesystem by specifying its filesystem ID instead of
> a path. The umount utility is changed to use this mechanism by
> default. This approach has a number of advantages:
> 
> - It avoids any lookup operations that could potentially block
>   forever, so filesystems such as NFS can be reliably unmounted
>   even if the server is not responding but looking up the root node
>   would require an RPC (maybe to an underlying filesystem).

VERY nice.