On Tue, Aug 6, 2019 at 9:23 AM Rob Clark <robdcl...@chromium.org> wrote: > > On Tue, Aug 6, 2019 at 8:50 AM Christoph Hellwig <h...@lst.de> wrote: > > > > On Tue, Aug 06, 2019 at 07:11:41AM -0700, Rob Clark wrote: > > > Agreed that drm_cflush_* isn't a great API. In this particular case > > > (IIUC), I need wb+inv so that there aren't dirty cache lines that drop > > > out to memory later, and so that I don't get a cache hit on > > > uncached/wc mmap'ing. > > > > So what is the use case here? Allocate pages using the page allocator > > (or CMA for that matter), and then mmaping them to userspace and never > > touching them again from the kernel? > > Currently, it is pages coming from tmpfs. Ideally we want pages that > are swappable when unpinned.
to be more specific, pages come from shmem_file_setup()/shmem_read_mapping_page() BR, -R
