drm: Create a driver hook for allocating GEM object structs.

The CMA helpers had no way for a driver to extend the struct with its
own fields.  Since the CMA helpers are mostly "Allocate a
drm_gem_cma_object, then fill in a few fields", it's hard to write as
pure helpers without passing in a driver callback for the allocate
step.

Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/drm_gem_cma_helper.c b/drivers/gpu/drm/drm_gem_cma_helper.c
index e109b49..0f7b00b 100644 (file)
--- a/drivers/gpu/drm/drm_gem_cma_helper.c
+++ b/drivers/gpu/drm/drm_gem_cma_helper.c
@@ -59,11 +59,13 @@ __drm_gem_cma_create(struct drm_device *drm, size_t size)
        struct drm_gem_object *gem_obj;
        int ret;
 
-       cma_obj = kzalloc(sizeof(*cma_obj), GFP_KERNEL);
-       if (!cma_obj)
+       if (drm->driver->gem_create_object)
+               gem_obj = drm->driver->gem_create_object(drm, size);
+       else
+               gem_obj = kzalloc(sizeof(*cma_obj), GFP_KERNEL);
+       if (!gem_obj)
                return ERR_PTR(-ENOMEM);
-
-       gem_obj = &cma_obj->base;
+       cma_obj = container_of(gem_obj, struct drm_gem_cma_object, base);
 
        ret = drm_gem_object_init(drm, gem_obj, size);
        if (ret)

diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index 0b921ae..22ff162 100644 (file)
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -580,6 +580,13 @@ struct drm_driver {
        int (*gem_open_object) (struct drm_gem_object *, struct drm_file *);
        void (*gem_close_object) (struct drm_gem_object *, struct drm_file *);
 
+       /**
+        * Hook for allocating the GEM object struct, for use by core
+        * helpers.
+        */
+       struct drm_gem_object *(*gem_create_object)(struct drm_device *dev,
+                                                   size_t size);
+
        /* prime: */
        /* export handle -> fd (see drm_gem_prime_handle_to_fd() helper) */
        int (*prime_handle_to_fd)(struct drm_device *dev, struct drm_file *file_priv,