[Intel-gfx] [PATCH 09/11] drm/i915: Release vma when the handle is closed

[Chris Wilson]

In order to prevent a leak of the vma on shared objects, we need to
hook into the object_close callback to destroy the vma on the object for
this file. However, if we destroyed that vma immediately we may cause
unexpected application stalls as we try to unbind a busy vma - hence we
defer the unbind to when we retire the vma.

Testcase: igt/gem_ppggtt/flink-and-close-vma-leak
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin at linux.intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com
---
 drivers/gpu/drm/i915/i915_drv.c     |  1 +
 drivers/gpu/drm/i915/i915_drv.h     |  1 +
 drivers/gpu/drm/i915/i915_gem.c     | 41 ++++++++++++++++++++++---------------
 drivers/gpu/drm/i915/i915_gem_gtt.c |  2 ++
 drivers/gpu/drm/i915/i915_gem_gtt.h |  1 +
 5 files changed, 30 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index e7eef5fd6918..70979339d58a 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -1656,6 +1656,7 @@ static struct drm_driver driver = {
 	.debugfs_init = i915_debugfs_init,
 	.debugfs_cleanup = i915_debugfs_cleanup,
 #endif
+	.gem_close_object = i915_gem_close_object,
 	.gem_free_object = i915_gem_free_object,
 	.gem_vm_ops = &i915_gem_vm_ops,
 
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index eb775eb1c693..696469a06715 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -2686,6 +2686,7 @@ struct drm_i915_gem_object *i915_gem_alloc_object(struct drm_device *dev,
 						  size_t size);
 struct drm_i915_gem_object *i915_gem_object_create_from_data(
 		struct drm_device *dev, const void *data, size_t size);
+void i915_gem_close_object(struct drm_gem_object *gem, struct drm_file *file);
 void i915_gem_free_object(struct drm_gem_object *obj);
 void i915_gem_vma_destroy(struct i915_vma *vma);
 
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 1d21c5b79215..7c13c27a6470 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2367,6 +2367,30 @@ i915_gem_object_flush_active(struct drm_i915_gem_object *obj)
 	return 0;
 }
 
+static void i915_vma_close(struct i915_vma *vma)
+{
+	RQ_BUG_ON(vma->closed);
+	vma->closed = true;
+
+	list_del_init(&vma->obj_link);
+	if (!vma->active)
+		WARN_ON(i915_vma_unbind(vma));
+}
+
+void i915_gem_close_object(struct drm_gem_object *gem,
+			   struct drm_file *file)
+{
+	struct drm_i915_gem_object *obj = to_intel_bo(gem);
+	struct drm_i915_file_private *fpriv = file->driver_priv;
+	struct i915_vma *vma, *vn;
+
+	mutex_lock(&obj->base.dev->struct_mutex);
+	list_for_each_entry_safe(vma, vn, &obj->vma_list, obj_link)
+		if (vma->vm->file == fpriv)
+			i915_vma_close(vma);
+	mutex_unlock(&obj->base.dev->struct_mutex);
+}
+
 /**
  * i915_gem_wait_ioctl - implements DRM_IOCTL_I915_GEM_WAIT
  * @DRM_IOCTL_ARGS: standard ioctl arguments
@@ -2577,9 +2601,6 @@ static int __i915_vma_unbind(struct i915_vma *vma, bool wait)
 		RQ_BUG_ON(vma->active);
 	}
 
-	if (list_empty(&vma->obj_link))
-		return 0;
-
 	if (!drm_mm_node_allocated(&vma->node)) {
 		i915_gem_vma_destroy(vma);
 		return 0;
@@ -3792,20 +3813,8 @@ void i915_gem_free_object(struct drm_gem_object *gem_obj)
 	trace_i915_gem_object_destroy(obj);
 
 	list_for_each_entry_safe(vma, next, &obj->vma_list, obj_link) {
-		int ret;
-
 		vma->pin_count = 0;
-		ret = i915_vma_unbind(vma);
-		if (WARN_ON(ret == -ERESTARTSYS)) {
-			bool was_interruptible;
-
-			was_interruptible = dev_priv->mm.interruptible;
-			dev_priv->mm.interruptible = false;
-
-			WARN_ON(i915_vma_unbind(vma));
-
-			dev_priv->mm.interruptible = was_interruptible;
-		}
+		i915_vma_close(vma);
 	}
 
 	/* Stolen objects don't hold a ref, but do hold pin count. Fix that up
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 5505603f52af..9f594c33bd0a 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -3240,6 +3240,8 @@ i915_vma_retire(struct drm_i915_gem_request_active *active,
 		return;
 
 	list_move_tail(&vma->vm_link, &vma->vm->inactive_list);
+	if (unlikely(vma->closed))
+		WARN_ON(i915_vma_unbind(vma));
 }
 
 static struct i915_vma *
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h
index c2f2c62ac88d..be7e8526b219 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.h
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.h
@@ -190,6 +190,7 @@ struct i915_vma {
 	unsigned int bound : 4;
 	unsigned int active : I915_NUM_RINGS;
 	bool is_ggtt : 1;
+	bool closed : 1;
 
 	/**
 	 * Support different GGTT views into the same object.
-- 
2.6.4