On Wed, Dec 18, 2019 at 04:25:28PM -0500, Martin K. Petersen wrote: > > Darrick, > > >> +#ifdef CONFIG_BLK_INLINE_ENCRYPTION > >> + struct bio_crypt_ctx *bi_crypt_context; > >> +#endif > > > > This grows struct bio even if we aren't actively using bi_crypt_context, > > and I thought Jens told us to stop making it bigger. :) > > Yeah. Why not use the bio integrity plumbing? It was explicitly designed > to attach things to a bio and have them consumed by the device driver. > There's not really any such thing as "use the bio integrity plumbing". blk-integrity just does blk-integrity; it's not a plumbing layer that allows other features to be supported. Well, in theory we could refactor and rename all the hooks to "blk-extra" and make them delegate to either blk-integrity or blk-crypto, but I think that would be overkill. What we could do, though, is say that at most one of blk-crypto and blk-integrity can be used at once on a given bio, and put the bi_integrity and bi_crypt_context pointers in union. (That would require allocating a REQ_INLINECRYPT bit so that we can tell what the pointer points to.) - Eric