On Mon, Apr 18, 2016 at 04:14:48PM +0800, Baolin Wang wrote: > On 18 April 2016 at 16:04, Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> wrote: > > On Mon, Apr 18, 2016 at 03:58:59PM +0800, Baolin Wang wrote: > >> > >> That depends on the hardware engine. Some cipher hardware engines > >> (like xts(aes) engine) can handle the intermediate values (IV) by > >> themselves in one bulk block, which means we can increase the size of > >> the request by merging request rather than always 512 bytes and thus > >> increase the hardware engine processing speed. But for some other > >> hardware engines (like cbc(aes) engine), they can not support bulk > >> block, must sector by sector. So the engine drivers can select the > >> suitable mode to do encryption/decryption. > > > > So what is this supposed to handle, xts or cbc? > > As I know, now cbc engine also need to handle requests sector by > sector, but for xts/ecb engine can support bulk block, which means can > merge requests. If it's just xts then why can't dm-crypt merge it and send a single request? Cheers, -- Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> 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-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
