1 files changed, 59 insertions, 30 deletions

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 2e10187cd0a0..702e5b89be22 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -118,6 +118,7 @@ int i915_gem_object_unbind(struct drm_i915_gem_object *obj,
 			   unsigned long flags)
 {
 	struct intel_runtime_pm *rpm = &to_i915(obj->base.dev)->runtime_pm;
+	bool vm_trylock = !!(flags & I915_GEM_OBJECT_UNBIND_VM_TRYLOCK);
 	LIST_HEAD(still_in_list);
 	intel_wakeref_t wakeref;
 	struct i915_vma *vma;
@@ -142,8 +143,6 @@ try_again:
 	while (!ret && (vma = list_first_entry_or_null(&obj->vma.list,
 						       struct i915_vma,
 						       obj_link))) {
-		struct i915_address_space *vm = vma->vm;
-
 		list_move_tail(&vma->obj_link, &still_in_list);
 		if (!i915_vma_is_bound(vma, I915_VMA_BIND_MASK))
 			continue;
@@ -153,40 +152,44 @@ try_again:
 			break;
 		}
 
+		/*
+		 * Requiring the vm destructor to take the object lock
+		 * before destroying a vma would help us eliminate the
+		 * i915_vm_tryget() here, AND thus also the barrier stuff
+		 * at the end. That's an easy fix, but sleeping locks in
+		 * a kthread should generally be avoided.
+		 */
 		ret = -EAGAIN;
-		if (!i915_vm_tryopen(vm))
+		if (!i915_vm_tryget(vma->vm))
 			break;
 
-		/* Prevent vma being freed by i915_vma_parked as we unbind */
-		vma = __i915_vma_get(vma);
 		spin_unlock(&obj->vma.lock);
 
-		if (vma) {
-			bool vm_trylock = !!(flags & I915_GEM_OBJECT_UNBIND_VM_TRYLOCK);
-			ret = -EBUSY;
-			if (flags & I915_GEM_OBJECT_UNBIND_ASYNC) {
-				assert_object_held(vma->obj);
-				ret = i915_vma_unbind_async(vma, vm_trylock);
-			}
+		/*
+		 * Since i915_vma_parked() takes the object lock
+		 * before vma destruction, it won't race us here,
+		 * and destroy the vma from under us.
+		 */
 
-			if (ret == -EBUSY && (flags & I915_GEM_OBJECT_UNBIND_ACTIVE ||
-					      !i915_vma_is_active(vma))) {
-				if (vm_trylock) {
-					if (mutex_trylock(&vma->vm->mutex)) {
-						ret = __i915_vma_unbind(vma);
-						mutex_unlock(&vma->vm->mutex);
-					} else {
-						ret = -EBUSY;
-					}
-				} else {
-					ret = i915_vma_unbind(vma);
+		ret = -EBUSY;
+		if (flags & I915_GEM_OBJECT_UNBIND_ASYNC) {
+			assert_object_held(vma->obj);
+			ret = i915_vma_unbind_async(vma, vm_trylock);
+		}
+
+		if (ret == -EBUSY && (flags & I915_GEM_OBJECT_UNBIND_ACTIVE ||
+				      !i915_vma_is_active(vma))) {
+			if (vm_trylock) {
+				if (mutex_trylock(&vma->vm->mutex)) {
+					ret = __i915_vma_unbind(vma);
+					mutex_unlock(&vma->vm->mutex);
 				}
+			} else {
+				ret = i915_vma_unbind(vma);
 			}
-
-			__i915_vma_put(vma);
 		}
 
-		i915_vm_close(vm);
+		i915_vm_put(vma->vm);
 		spin_lock(&obj->vma.lock);
 	}
 	list_splice_init(&still_in_list, &obj->vma.list);
@@ -936,8 +939,19 @@ new_vma:
 			if (i915_vma_is_pinned(vma) || i915_vma_is_active(vma))
 				return ERR_PTR(-ENOSPC);
 
+			/*
+			 * If this misplaced vma is too big (i.e, at-least
+			 * half the size of aperture) or hasn't been pinned
+			 * mappable before, we ignore the misplacement when
+			 * PIN_NONBLOCK is set in order to avoid the ping-pong
+			 * issue described above. In other words, we try to
+			 * avoid the costly operation of unbinding this vma
+			 * from the GGTT and rebinding it back because there
+			 * may not be enough space for this vma in the aperture.
+			 */
 			if (flags & PIN_MAPPABLE &&
-			    vma->fence_size > ggtt->mappable_end / 2)
+			    (vma->fence_size > ggtt->mappable_end / 2 ||
+			    !i915_vma_is_map_and_fenceable(vma)))
 				return ERR_PTR(-ENOSPC);
 		}
 
@@ -1213,25 +1227,40 @@ void i915_gem_cleanup_early(struct drm_i915_private *dev_priv)
 int i915_gem_open(struct drm_i915_private *i915, struct drm_file *file)
 {
 	struct drm_i915_file_private *file_priv;
-	int ret;
+	struct i915_drm_client *client;
+	int ret = -ENOMEM;
 
 	DRM_DEBUG("\n");
 
 	file_priv = kzalloc(sizeof(*file_priv), GFP_KERNEL);
 	if (!file_priv)
-		return -ENOMEM;
+		goto err_alloc;
+
+	client = i915_drm_client_add(&i915->clients);
+	if (IS_ERR(client)) {
+		ret = PTR_ERR(client);
+		goto err_client;
+	}
 
 	file->driver_priv = file_priv;
 	file_priv->dev_priv = i915;
 	file_priv->file = file;
+	file_priv->client = client;
 
 	file_priv->bsd_engine = -1;
 	file_priv->hang_timestamp = jiffies;
 
 	ret = i915_gem_context_open(i915, file);
 	if (ret)
-		kfree(file_priv);
+		goto err_context;
+
+	return 0;
 
+err_context:
+	i915_drm_client_put(client);
+err_client:
+	kfree(file_priv);
+err_alloc:
 	return ret;
 }