drm/i915: Add an optional selection from i915 of CONFIG_MMU_NOTIFIER

userptr requires mmu-notifier for full unprivileged support. Most
systems have mmu-notifier support already enabled as a requirement for
virtualisation support, but we should make the option for i915 to take
advantage of mmu-notifiers explicit (and enable by default so that
regular userspace can take advantage of passing client memory to the
GPU.)

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1452503961-14837-3-git-send-email-chris@chris-wilson.co.uk

diff --git a/drivers/gpu/drm/i915/Kconfig b/drivers/gpu/drm/i915/Kconfig
index 4c59793c4ccb6e01865dbfe97efe385b80a8fae1..20a5d0455e19dd71a5ae61e0fc89357cdec03c01 100644 (file)
--- a/drivers/gpu/drm/i915/Kconfig
+++ b/drivers/gpu/drm/i915/Kconfig
@@ -45,3 +45,14 @@ config DRM_I915_PRELIMINARY_HW_SUPPORT
          option changes the default for that module option.
 
          If in doubt, say "N".
+
+config DRM_I915_USERPTR
+       bool "Always enable userptr support"
+       depends on DRM_I915
+       select MMU_NOTIFIER
+       default y
+       help
+         This option selects CONFIG_MMU_NOTIFIER if it isn't already
+         selected to enabled full userptr support.
+
+         If in doubt, say "Y".