[Intel-gfx] [PATCH 15/29] drm/i915: Improve VMA comments

[Ben Widawsky]

Signed-off-by: Ben Widawsky <ben at bwidawsk.net>
---
 drivers/gpu/drm/i915/i915_drv.h | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 2579e96..dbfffb2 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -533,7 +533,12 @@ struct i915_hw_ppgtt {
 	int (*enable)(struct drm_device *dev);
 };
 
-/* To make things as simple as possible (ie. no refcounting), a VMA's lifetime
+/**
+ * A VMA represents a GEM BO that is bound into an address space. Therefore, a
+ * VMA's presence cannot be guaranteed before binding, or after unbinding the
+ * object into/from the address space.
+ *
+ * To make things as simple as possible (ie. no refcounting), a VMA's lifetime
  * will always be <= an objects lifetime. So object refcounting should cover us.
  */
 struct i915_vma {
-- 
1.8.3.4