On Wed, 10 Apr 2019 17:57:50 +0200 Halil Pasic <pasic@xxxxxxxxxxxxx> wrote: > On Wed, 10 Apr 2019 11:20:48 +0200 > Cornelia Huck <cohuck@xxxxxxxxxx> wrote: > > > On Fri, 5 Apr 2019 01:16:10 +0200 > > Halil Pasic <pasic@xxxxxxxxxxxxx> wrote: > > > > > Enhanced virtualization protection technology may require the use of > > > bounce buffers for I/O. While support for this was built into the > > > virtio core, virtio-ccw wasn't changed accordingly. > > > > > > Thus what needs to be done to bring virtio-ccw up to speed with > > > respect to this is: > > > * use some 'new' common virtio stuff > > > * make sure that virtio-ccw specific stuff uses shared memory when > > > talking to the hypervisor (except communication blocks like ORB, > > > these are handled by the hypervisor) > > > * make sure the DMA API does what is necessary to talk through shared > > > memory if we are a protected virtualization guest. > > > * make sure the common IO layer plays along as well (airqs, sense). > > > > It would be good to have a summary somewhere in the code (or > > Documentation/) as to what needs the dma treatment and what doesn't, > > for later reference. We don't want people to accidentally break things > > (especially if they cannot refer to architecture documentation - or > > will at least some of that be published?) > > > > I can put documentation on my TODO list. This cover letter was also > supposed to provide a bird's-eye view on what needs to be done. Some comments in the code to prevent further headscratching are also a good idea. > > > > > > > The series is structured in incremental fashion: some of the changes > > > are overridden by following patches. The main reason why is that > > > this is how I developed. But I think it ain't bad for the didactic > > > and we are a bit more flexible with regards to throwing out some of > > > the stuff in the end. > > > > FWIW, I think reshuffling the patches in the next iteration would ease > > review. > > > > Can you please tell me more about what is desired here? I mean, I made > some tentative proposals on squashing some patches together. I don't > remember any requests to reorder patches or split. Just try to avoid to rewrite things multiple times -- if we agree on the end result, we should be able to go there directly :)
