[CRIU] Sync TODO-s for mount.c work

[Pavel Emelyanov]

On 04/22/2015 06:35 PM, Oleg Nesterov wrote:
> On 04/22, Tycho Andersen wrote:
>>
>> In this case you have to use --ext-mount-map KEY:VAL as in the good
>> old days before --ext-mount-map auto.
> 
> I _suspected_ this ;) Thanks.
> 
> OK, before I dive into the sources, could you please tell me what
> should I pass as KEY:VAL pair? (I didn't read this code yet and I
> am not sure if I can understand it, at least quickly).

The --ext-mount-map works like this.

On dump you say $mountpoint:$id pair and criu saves $id into image
file for mountpoint named $mountpoint.

On restore you say $id:$root and criu would bind mount host's $root
into the mountpoint with id $id.

-- Pavel