Re: [1/1 take 2] HIFN 795x driver.

[Evgeniy Polyakov <johnpol@2ka.mipt.ru>]

Hi Herbert.

On Wed, Oct 03, 2007 at 07:54:05PM +0800, Herbert Xu (herbert@gondor.apana.org.au) wrote:
> > It has to be multiple of blocksize. I.e. it is impossible to 
> > crypt one byte - hardware will stall, DES test provides two bytes as
> > input - this will not work. If that is going to be handled in driver,
> > then it will relocate. I'm not sure it is the right decision.
> 
> Right.  However you can't force the user to give you data that's
> always layed out in blocks.  For example, an IP fragment might give
> you an sg element that's only half an AES block.
> 
> You should either use the blkcipher walking helpers to avoid
> this or do your own copying when you detect that you have a
> partial block in an sg element.

Ok, I will think more about this issues and ways to resolve the problem.

> Also, the MAY_BACKLOG option must be implemented or dm-crypt
> won't work properly.

What is may backlog option? I did not find it in cryptd.c, which I used
for reference. I found a backlog variables in the driver, but without
any signs for the outside world - queue is initialized and backlog is
being set to that queue - since there is a dequeueing code, what is a
purpose for backlog in that case?

-- 
	Evgeniy Polyakov