drm/radeon: make MMU_NOTIFIER optional

In cases where MMU_NOTIFIER is not available, userptr will not be
available.  Similar to i915, although not making an exception for
CAP_SYS_ADMIN.

The proposed userspace patches for userptr seem to handle the fall-
back properly, so a userptr-less kernel should not be a problem.

Signed-off-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
index d15e3c0c09f5..93e407b7e7a7 100644
--- a/drivers/gpu/drm/radeon/radeon.h
+++ b/drivers/gpu/drm/radeon/radeon.h
@@ -1780,8 +1780,16 @@ void radeon_test_syncing(struct radeon_device *rdev);
 /*
  * MMU Notifier
  */
+#if defined(CONFIG_MMU_NOTIFIER)
 int radeon_mn_register(struct radeon_bo *bo, unsigned long addr);
 void radeon_mn_unregister(struct radeon_bo *bo);
+#else
+static inline int radeon_mn_register(struct radeon_bo *bo, unsigned long addr)
+{
+        return -ENODEV;
+}
+static inline void radeon_mn_unregister(struct radeon_bo *bo) {}
+#endif
 
 /*
  * Debugfs