[PATCH] mkfs: support block map for blob devices

[Nithurshen Karthikeyan]

Hi Yifan Zhao,

> Hi Nithurshen,
>
> Each line of the commit message must not exceed 72 characters.

I don't know how it went wrong, but I will double check from this time.

> It's impossible for 32-bit block map entries to support 48bit mode.
>
> I think we should err out instead of enabling 48bit here.
>
>
> BTW, it seems the erofs-utils codebase could not read a chunk-based
> EROFS image
>
> with block map and extra devices (but in-kernel implementation could),
> as erofs_map_dev() does
>

I have taken care of this in v2 Patch.

> Could you help also fix this? If you are
> interested please also add related
>
> testcases in erofs/erofsnightly repo.

Sure. I am interested.
I will work on it shortly.

Thanks and regards
Nithurshen