3 files changed, 55 insertions, 18 deletions

diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
index 5dad6b9d0de..88d3368ffdd 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -463,6 +463,26 @@ drm_gem_object_handle_free(struct kref *kref)
 }
 EXPORT_SYMBOL(drm_gem_object_handle_free);
 
+void drm_gem_vm_open(struct vm_area_struct *vma)
+{
+	struct drm_gem_object *obj = vma->vm_private_data;
+
+	drm_gem_object_reference(obj);
+}
+EXPORT_SYMBOL(drm_gem_vm_open);
+
+void drm_gem_vm_close(struct vm_area_struct *vma)
+{
+	struct drm_gem_object *obj = vma->vm_private_data;
+	struct drm_device *dev = obj->dev;
+
+	mutex_lock(&dev->struct_mutex);
+	drm_gem_object_unreference(obj);
+	mutex_unlock(&dev->struct_mutex);
+}
+EXPORT_SYMBOL(drm_gem_vm_close);
+
+
 /**
  * drm_gem_mmap - memory map routine for GEM objects
  * @filp: DRM file pointer
@@ -524,6 +544,14 @@ int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
 #endif
 	vma->vm_page_prot = __pgprot(prot);
 
+	/* Take a ref for this mapping of the object, so that the fault
+	 * handler can dereference the mmap offset's pointer to the object.
+	 * This reference is cleaned up by the corresponding vm_close
+	 * (which should happen whether the vma was created by this call, or
+	 * by a vm_open due to mremap or partial unmap or whatever).
+	 */
+	drm_gem_object_reference(obj);
+
 	vma->vm_file = filp;	/* Needed for drm_vm_open() */
 	drm_vm_open_locked(vma);
 
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index aac12ee31a4..a31cbdbc3c5 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -94,6 +94,8 @@ static int i915_resume(struct drm_device *dev)
 
 static struct vm_operations_struct i915_gem_vm_ops = {
 	.fault = i915_gem_fault,
+	.open = drm_gem_vm_open,
+	.close = drm_gem_vm_close,
 };
 
 static struct drm_driver driver = {
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 07885817883..ac534c9a2f8 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -607,8 +607,6 @@ int i915_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 	case -EAGAIN:
 		return VM_FAULT_OOM;
 	case -EFAULT:
-	case -EBUSY:
-		DRM_ERROR("can't insert pfn??  fault or busy...\n");
 		return VM_FAULT_SIGBUS;
 	default:
 		return VM_FAULT_NOPAGE;
@@ -684,6 +682,30 @@ out_free_list:
 	return ret;
 }
 
+static void
+i915_gem_free_mmap_offset(struct drm_gem_object *obj)
+{
+	struct drm_device *dev = obj->dev;
+	struct drm_i915_gem_object *obj_priv = obj->driver_private;
+	struct drm_gem_mm *mm = dev->mm_private;
+	struct drm_map_list *list;
+
+	list = &obj->map_list;
+	drm_ht_remove_item(&mm->offset_hash, &list->hash);
+
+	if (list->file_offset_node) {
+		drm_mm_put_block(list->file_offset_node);
+		list->file_offset_node = NULL;
+	}
+
+	if (list->map) {
+		drm_free(list->map, sizeof(struct drm_map), DRM_MEM_DRIVER);
+		list->map = NULL;
+	}
+
+	obj_priv->mmap_offset = 0;
+}
+
 /**
  * i915_gem_get_gtt_alignment - return required GTT alignment for an object
  * @obj: object to check
@@ -2896,9 +2918,6 @@ int i915_gem_init_object(struct drm_gem_object *obj)
 void i915_gem_free_object(struct drm_gem_object *obj)
 {
 	struct drm_device *dev = obj->dev;
-	struct drm_gem_mm *mm = dev->mm_private;
-	struct drm_map_list *list;
-	struct drm_map *map;
 	struct drm_i915_gem_object *obj_priv = obj->driver_private;
 
 	while (obj_priv->pin_count > 0)
@@ -2909,19 +2928,7 @@ void i915_gem_free_object(struct drm_gem_object *obj)
 
 	i915_gem_object_unbind(obj);
 
-	list = &obj->map_list;
-	drm_ht_remove_item(&mm->offset_hash, &list->hash);
-
-	if (list->file_offset_node) {
-		drm_mm_put_block(list->file_offset_node);
-		list->file_offset_node = NULL;
-	}
-
-	map = list->map;
-	if (map) {
-		drm_free(map, sizeof(*map), DRM_MEM_DRIVER);
-		list->map = NULL;
-	}
+	i915_gem_free_mmap_offset(obj);
 
 	drm_free(obj_priv->page_cpu_valid, 1, DRM_MEM_DRIVER);
 	drm_free(obj->driver_private, 1, DRM_MEM_DRIVER);