Re: [PATCH 0/2] scsi: ufs: add real time/inline crypto support to UFS HCD

From: Christoph Hellwig
Date: Wed Dec 12 2018 - 02:40:32 EST


On Tue, Dec 11, 2018 at 06:22:27PM +0000, Parshuram Raju Thombare wrote:
> One reason of using device mapper here is to use existing tools like
> 'dmsetup', otherwise some user space application is needed and may be
> some changes in block layer to pass the crypto information (crypto
> algorithm, key etc) till ufs driver.

Yes, so what? We also don't use dmsetup to set up TCG OPAL based
encryption either.

> Another reason is supporting multiple UFS devices. I think, as you said
> UFS crypto support can be added by some change in ufs driver and block
> layer glue. But to support multiple UFS crypto devices having different
> crypto configs (crypto algorithms, key size etc), crypto context need to
> be saved per crypto device which may need some changes in block layer code.

I don't think we need device mapper for that. We can hav the crypto
state hanging off the ufs host, or request_queue if we decide to
implement it generic in the block layer.