On Wed, Apr 14, 2010 at 09:37:47AM +0300, Dmitry Kasatkin wrote: > > Like just with import/export. > Problems for hw: > > 1. To have a good performance with DMA we need to have large buffer. > Not just 64 bytes block. state becomes large
Sure. But it shouldn't be up to the driver to merge operations. Higher layers (either the end-user or the crypto API) should perform merging. We don't put request merging into storage drivers for a reason. > 2. supporting concurrent requests means switching HW state and it takes > a time. Well that's just the way it is. I'm not saying that it's going to occur frequently, but if it does, you need to support it. > All that burden significantly slowdown hw acceleration and increase CPU > load. > > I guess my points are understandable. I understand your concerns, but these are really limitations common to all off-chip acceleration. If you have to write drivers for them, then you'll have to deal with these issues. Cheers, -- Visit Openswan at http://www.openswan.org/ Email: Herbert Xu ~{PmV>HI~} <[email protected]> Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
