[PATCH] unstable/linux-dmabuf: Add 'direct_display' flag

[Drew DeVault]

Can you elaborate more on non-DRM use-cases? Most compositors are
already going to use direct scan-out as much as possible, and can make
reasonably well informed choices about when to do so. For example,
fullscreen surfaces will generally always be scanned out if possible.
More interesting approaches could include intelligently picking the most
frequently updated buffers to be placed on planes, or the most optimal
arrangement for a given combination of pixel formats.

In addition, the implication that the compositor shouldn't do things
like letting the user take screenshots when views like this are being
shown is a chilling effect on non-DRM use-cases, in which taking a
screenshot is a perfectly reasonable thing to do.

I don't really like the idea of DRM-enabling features being added to
linux-dmabuf with this level of justification for non-DRM use-cases.