[RFC PATCH 3/6] drm/gpusvm: Add drm_gpusvm_in_notifier_* helpers

["Thomas Hellström" <thomas.hellstrom@linux.intel.com>]

From: Matthew Brost <matthew.brost@intel.com>

Abstract drm_gpusvm_in_notifier_lock/unlock with helpers. Intended usage
is a client side 2nd pass of a MMU notifier.

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
---
 include/drm/drm_gpusvm.h | 22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/include/drm/drm_gpusvm.h b/include/drm/drm_gpusvm.h
index 8b5e159857fc..4bdbe10685cf 100644
--- a/include/drm/drm_gpusvm.h
+++ b/include/drm/drm_gpusvm.h
@@ -313,7 +313,7 @@ void drm_gpusvm_range_set_unmapped(struct drm_gpusvm_range *range,
 #endif
 
 /**
- * drm_gpusvm_notifier_lock() - Lock GPU SVM notifier
+ * drm_gpusvm_notifier_lock() - Lock GPU SVM notifier, client side
  * @gpusvm__: Pointer to the GPU SVM structure.
  *
  * Abstract client usage GPU SVM notifier lock, take lock
@@ -322,7 +322,7 @@ void drm_gpusvm_range_set_unmapped(struct drm_gpusvm_range *range,
 	down_read(&(gpusvm__)->notifier_lock)
 
 /**
- * drm_gpusvm_notifier_unlock() - Unlock GPU SVM notifier
+ * drm_gpusvm_notifier_unlock() - Unlock GPU SVM notifier, client side
  * @gpusvm__: Pointer to the GPU SVM structure.
  *
  * Abstract client usage GPU SVM notifier lock, drop lock
@@ -330,6 +330,24 @@ void drm_gpusvm_range_set_unmapped(struct drm_gpusvm_range *range,
 #define drm_gpusvm_notifier_unlock(gpusvm__)	\
 	up_read(&(gpusvm__)->notifier_lock)
 
+/**
+ * drm_gpusvm_in_notifier_lock() - Lock GPU SVM notifier, in notifier
+ * @gpusvm__: Pointer to the GPU SVM structure.
+ *
+ * Abstract in notifier (2nd pass) usage GPU SVM notifier lock, take lock
+ */
+#define drm_gpusvm_in_notifier_lock(gpusvm__)	\
+	down_write(&(gpusvm__)->notifier_lock)
+
+/**
+ * drm_gpusvm_in_notifier_unlock() - Unlock GPU SVM notifier, in notifier
+ * @gpusvm__: Pointer to the GPU SVM structure.
+ *
+ * Abstract in notifier (2nd pass) GPU SVM notifier lock, drop lock
+ */
+#define drm_gpusvm_in_notifier_unlock(gpusvm__)	\
+	up_write(&(gpusvm__)->notifier_lock)
+
 /**
  * drm_gpusvm_range_start() - GPU SVM range start address
  * @range: Pointer to the GPU SVM range
-- 
2.50.1