On Thu, 10 Feb 2005, Fruhwirth Clemens wrote: > Because a tweak is different from an IV. There can be an arbitrary > number of tweaks. For instance, EME takes 1 tweak per 512 bytes. If you > have a 4k page to encrypt, you have to process 8 tweaks of whatever > size. > Therefore, you need 3 scatterlists: src, dst and the running along > tweak.
The purpose of the scatterlists is to be able to process discontigous data at the page level. The tweak, as I understand it, is something which you generate, and it is not inherently likely to be page-level clumps of data. It does not ever need to be kmapped. What you really need to do is use an array for the tweak (or possibly a structure which maintains state about it if needed). - James -- James Morris <[EMAIL PROTECTED]> - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
