drm/vkms: Drop custom vkms_dumb_map().

This is the same as the default drm_gem_dumb_map_offset()
implementation, except that this one missed the ban on userspace
mapping an imported dmabuf (which seems like intended common behavior
for drivers).
Signed-off-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20181126215929.20546-1-eric@anholt.netAcked-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/vkms/vkms_drv.c

@@ -68,7 +68,6 @@ static struct drm_driver vkms_driver = {
 	.release		= vkms_release,
 	.fops			= &vkms_driver_fops,
 	.dumb_create		= vkms_dumb_create,
-	.dumb_map_offset	= vkms_dumb_map,
 	.gem_vm_ops		= &vkms_gem_vm_ops,
 	.gem_free_object_unlocked = vkms_gem_free_object,
 	.get_vblank_timestamp	= vkms_get_vblank_timestamp,

drivers/gpu/drm/vkms/vkms_drv.h

@@ -127,9 +127,6 @@ vm_fault_t vkms_gem_fault(struct vm_fault *vmf);
 int vkms_dumb_create(struct drm_file *file, struct drm_device *dev,
 		     struct drm_mode_create_dumb *args);
 
-int vkms_dumb_map(struct drm_file *file, struct drm_device *dev,
-		  u32 handle, u64 *offset);
-
 void vkms_gem_free_object(struct drm_gem_object *obj);
 
 int vkms_gem_vmap(struct drm_gem_object *obj);

drivers/gpu/drm/vkms/vkms_gem.c

@@ -153,32 +153,6 @@ int vkms_dumb_create(struct drm_file *file, struct drm_device *dev,
 	return 0;
 }
 
-int vkms_dumb_map(struct drm_file *file, struct drm_device *dev,
-		  u32 handle, u64 *offset)
-{
-	struct drm_gem_object *obj;
-	int ret;
-
-	obj = drm_gem_object_lookup(file, handle);
-	if (!obj)
-		return -ENOENT;
-
-	if (!obj->filp) {
-		ret = -EINVAL;
-		goto unref;
-	}
-
-	ret = drm_gem_create_mmap_offset(obj);
-	if (ret)
-		goto unref;
-
-	*offset = drm_vma_node_offset_addr(&obj->vma_node);
-unref:
-	drm_gem_object_put_unlocked(obj);
-
-	return ret;
-}
-
 static struct page **_get_pages(struct vkms_gem_object *vkms_obj)
 {
 	struct drm_gem_object *gem_obj = &vkms_obj->gem;