--- drivers/gpu/drm/drm_gem.c | 88 +++++++++++++++++++++++++++++++++++++++++++++ include/drm/drmP.h | 3 ++ 2 files changed, 91 insertions(+), 0 deletions(-)
diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index 2b997d2..809358a 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -273,6 +273,94 @@ again: } EXPORT_SYMBOL(drm_gem_handle_create);
+ +/** + * drm_gem_free_mmap_offset - release a fake mmap offset for an object + * @obj: obj in question + * + * This routine frees fake offsets allocated by drm_gem_create_mmap_offset(). + */ +void +drm_gem_free_mmap_offset(struct drm_gem_object *obj) +{ + struct drm_device *dev = obj->dev; + struct drm_gem_mm *mm = dev->mm_private; + struct drm_map_list *list = &obj->map_list; + + drm_ht_remove_item(&mm->offset_hash, &list->hash); + drm_mm_put_block(list->file_offset_node); + kfree(list->map); + list->map = NULL; +} +EXPORT_SYMBOL(drm_gem_free_mmap_offset); + +/** + * drm_gem_create_mmap_offset - create a fake mmap offset for an object + * @obj: obj in question + * + * GEM memory mapping works by handing back to userspace a fake mmap offset + * it can use in a subsequent mmap(2) call. The DRM core code then looks + * up the object based on the offset and sets up the various memory mapping + * structures. + * + * This routine allocates and attaches a fake offset for @obj. + */ +int +drm_gem_create_mmap_offset(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_local_map *map; + int ret = 0; + + /* Set the object up for mmap'ing */ + list = &obj->map_list; + list->map = kzalloc(sizeof(struct drm_map_list), GFP_KERNEL); + if (!list->map) + return -ENOMEM; + + map = list->map; + map->type = _DRM_GEM; + map->size = obj->size; + map->handle = obj; + + /* Get a DRM GEM mmap offset allocated... */ + list->file_offset_node = drm_mm_search_free(&mm->offset_manager, + obj->size / PAGE_SIZE, 0, 0); + + if (!list->file_offset_node) { + DRM_ERROR("failed to allocate offset for bo %d\n", obj->name); + ret = -ENOSPC; + goto out_free_list; + } + + list->file_offset_node = drm_mm_get_block(list->file_offset_node, + obj->size / PAGE_SIZE, 0); + if (!list->file_offset_node) { + ret = -ENOMEM; + goto out_free_list; + } + + list->hash.key = list->file_offset_node->start; + ret = drm_ht_insert_item(&mm->offset_hash, &list->hash); + if (ret) { + DRM_ERROR("failed to add to map hash\n"); + goto out_free_mm; + } + + return 0; + +out_free_mm: + drm_mm_put_block(list->file_offset_node); +out_free_list: + kfree(list->map); + list->map = NULL; + + return ret; +} +EXPORT_SYMBOL(drm_gem_create_mmap_offset); + /** Returns a reference to the object named by the handle. */ struct drm_gem_object * drm_gem_object_lookup(struct drm_device *dev, struct drm_file *filp, diff --git a/include/drm/drmP.h b/include/drm/drmP.h index 111e98f..ec156c3 100644 --- a/include/drm/drmP.h +++ b/include/drm/drmP.h @@ -1622,6 +1622,9 @@ drm_gem_object_handle_unreference_unlocked(struct drm_gem_object *obj) drm_gem_object_unreference_unlocked(obj); }
+void drm_gem_free_mmap_offset(struct drm_gem_object *obj); +int drm_gem_create_mmap_offset(struct drm_gem_object *obj); + struct drm_gem_object *drm_gem_object_lookup(struct drm_device *dev, struct drm_file *filp, u32 handle);