On Tue, Jun 28, 2016 at 10:35:31AM -0700, Andy Lutomirski wrote: > > Do you mean this code:
Yes. > I'm wondering why support for scatterlists is all-or-nothing. Why > can't we initialize a hash object and then alternate between passing > it scatterlists and pointers? Because once you have started hashing the hash state is not stored in a consistent format. Our software code may maintain one format while a hardware implementation could do something else altogether. So you have to stick with one implementation throughout a particular hashing session. > I'm guessing that ahash enables async operation and shash is > synchronous only. If I'm right, I understand why ahash requires a > scatterlist. What I don't understand is why shash can't also accept a > scatterlist. It appears that most of the ahash users in the tree > actually want synchronous crypto and are presumably using ahash for > some other reason such as ahash's ability to hash via scatterlist (in > this case, struct page *). ahash is meant to be the interface everyone uses regardless of whether they want sync-only or async. shash should only be used for small amounts of hashing on virtual addresses. Cheers, -- Email: Herbert Xu <herb...@gondor.apana.org.au> Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
