On 3 June 2016 at 18:09, Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> wrote: > On Fri, Jun 03, 2016 at 05:23:59PM +0800, Baolin Wang wrote: >> >> Assuming one 64K size bio coming, we can map the whole bio with one sg >> table in crypt_convert_bulk_block() function. But if we send this bulk >> request to crypto layer, we should divide the bulk request into small >> requests, and each small request should be one sector size (512 bytes) >> with assuming the correct IV, but we need to allocate small requests >> memory for the division, which will not good for IO mapping, and how >> each small request connect to dm-crypt (how to notify the request is >> done?)? > > Why won't it be good? The actual AES block size is 16 and yet we Like I said, we should avoid memory allocation to improve efficiency in the IO path. Another hand is how the divided small requests (allocate request memory at crypt layer) connect with dm-crypt? Since dm-crypt just send one bulk request to crypt layer, but it will be divided into small requests at crypt layer. > have no trouble when you feed it a block of 512 bytes. That's right. -- Baolin.wang Best Regards -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
