[PATCH 124/124] drm/i915: Allow i915_gem_object_pin_pages() to be nested

[Chris Wilson]

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_gem_object.c |  5 +++--
 drivers/gpu/drm/i915/i915_gem_object.h | 25 +++++++++++++++++--------
 2 files changed, 20 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_object.c b/drivers/gpu/drm/i915/i915_gem_object.c
index b459acecffc8..dc91b4a106f8 100644
--- a/drivers/gpu/drm/i915/i915_gem_object.c
+++ b/drivers/gpu/drm/i915/i915_gem_object.c
@@ -235,11 +235,12 @@ static int ____i915_gem_object_get_pages(struct drm_i915_gem_object *obj)
  * either as a result of memory pressure (reaping pages under the shrinker)
  * or as the object is itself released.
  */
-int __i915_gem_object_get_pages(struct drm_i915_gem_object *obj)
+int __i915_gem_object_get_pages(struct drm_i915_gem_object *obj,
+				enum i915_mm_subclass subclass)
 {
 	int err;
 
-	err = mutex_lock_interruptible(&obj->mm.lock);
+	err = mutex_lock_interruptible_nested(&obj->mm.lock, subclass);
 	if (err)
 		return err;
 
diff --git a/drivers/gpu/drm/i915/i915_gem_object.h b/drivers/gpu/drm/i915/i915_gem_object.h
index a8b5d693cfc6..8128c8169456 100644
--- a/drivers/gpu/drm/i915/i915_gem_object.h
+++ b/drivers/gpu/drm/i915/i915_gem_object.h
@@ -530,13 +530,21 @@ dma_addr_t
 i915_gem_object_get_dma_address(struct drm_i915_gem_object *obj,
 				unsigned long n);
 
+enum i915_mm_subclass { /* lockdep subclass for obj->mm.lock */
+	I915_MM_NORMAL = 0,
+	I915_MM_PROXY,
+	I915_MM_SHRINKER
+};
+
 void __i915_gem_object_set_pages(struct drm_i915_gem_object *obj,
 				 struct sg_table *pages,
 				 unsigned int sg_page_sizes);
-int __i915_gem_object_get_pages(struct drm_i915_gem_object *obj);
+int __i915_gem_object_get_pages(struct drm_i915_gem_object *obj,
+				enum i915_mm_subclass subclass);
 
 static inline int __must_check
-i915_gem_object_pin_pages(struct drm_i915_gem_object *obj)
+i915_gem_object_pin_pages_nested(struct drm_i915_gem_object *obj,
+				 enum i915_mm_subclass subclass)
 {
 	might_lock(&obj->mm.lock);
 
@@ -545,7 +553,13 @@ i915_gem_object_pin_pages(struct drm_i915_gem_object *obj)
 	if (atomic_inc_not_zero(&obj->mm.pages_pin_count))
 		return 0;
 
-	return __i915_gem_object_get_pages(obj);
+	return __i915_gem_object_get_pages(obj, subclass);
+}
+
+static inline int __must_check
+i915_gem_object_pin_pages(struct drm_i915_gem_object *obj)
+{
+	return i915_gem_object_pin_pages_nested(obj, I915_MM_NORMAL);
 }
 
 static inline bool
@@ -583,11 +597,6 @@ i915_gem_object_unpin_pages(struct drm_i915_gem_object *obj)
 	__i915_gem_object_unpin_pages(obj);
 }
 
-enum i915_mm_subclass { /* lockdep subclass for obj->mm.lock */
-	I915_MM_NORMAL = 0,
-	I915_MM_SHRINKER
-};
-
 void __i915_gem_object_put_pages(struct drm_i915_gem_object *obj,
 				 enum i915_mm_subclass subclass);
 void __i915_gem_object_invalidate(struct drm_i915_gem_object *obj);
-- 
2.19.0.rc2