Re: [PATCH 6/9] dm crypt: support diskcipher

[boojin.kim]

On Wed, Aug 21, 2019 at 09:13:36AM +0200, Milan Broz wrote: 
>
> NACK.
> 
> The whole principle of dm-crypt target is that it NEVER EVER submits
> plaintext data down the stack in bio.
> 
> If you want to do some lower/higher layer encryption, use key management
> on a different layer.
> So here, just setup encryption for fs, do not stack it with dm-crypt.
> 
> Also, dm-crypt is software-independent solution
> (software-based full disk encryption), it must not depend on
> any underlying hardware.
> Hardware can be of course used used for acceleration, but then
> just implement proper crypto API module that accelerates particular
cipher.

I'm sorry for breaking the basic rules of dm-crypt. 
But, if I want to use the H/W crypto accelerator running in storage
controller,
I have to drop plaintext to bio.
I think the "proper crypto API module" that you mentioned is diskcipher
because diskcipher isn't only for FMP.
Diskcipher is a crypto API that supports encryption on storage controllers.

Thanks
Boojin Kim