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  • 	efiobj = efi_search_obj(handle);
    	if (!efiobj)
    		return EFI_EXIT(EFI_INVALID_PARAMETER);
    
    	/* Count protocols */
    	list_for_each(protocol_handle, &efiobj->protocols) {
    		++*protocol_buffer_count;
    	}
    
    	/* Copy guids */
    	if (*protocol_buffer_count) {
    		size_t j = 0;
    
    		buffer_size = sizeof(efi_guid_t *) * *protocol_buffer_count;
    		r = efi_allocate_pool(EFI_ALLOCATE_ANY_PAGES, buffer_size,
    				      (void **)protocol_buffer);
    		if (r != EFI_SUCCESS)
    			return EFI_EXIT(r);
    		list_for_each(protocol_handle, &efiobj->protocols) {
    			struct efi_handler *protocol;
    
    			protocol = list_entry(protocol_handle,
    					      struct efi_handler, link);
    			(*protocol_buffer)[j] = (void *)protocol->guid;
    			++j;
    
    		}
    	}
    
    	return EFI_EXIT(EFI_SUCCESS);
    
    /*
     * Locate handles implementing a protocol.
     *
     * This function implements the LocateHandleBuffer service.
     * See the Unified Extensible Firmware Interface (UEFI) specification
     * for details.
     *
     * @search_type		selection criterion
     * @protocol		GUID of the protocol
     * @search_key		registration key
     * @no_handles		number of returned handles
     * @buffer		buffer with the returned handles
     * @return		status code
     */
    
    static efi_status_t EFIAPI efi_locate_handle_buffer(
    			enum efi_locate_search_type search_type,
    
    			const efi_guid_t *protocol, void *search_key,
    
    			efi_uintn_t *no_handles, efi_handle_t **buffer)
    
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    	EFI_ENTRY("%d, %pUl, %p, %p, %p", search_type, protocol, search_key,
    
    		  no_handles, buffer);
    
    
    	if (!no_handles || !buffer) {
    		r = EFI_INVALID_PARAMETER;
    		goto out;
    	}
    	*no_handles = 0;
    	*buffer = NULL;
    	r = efi_locate_handle(search_type, protocol, search_key, &buffer_size,
    			      *buffer);
    	if (r != EFI_BUFFER_TOO_SMALL)
    		goto out;
    	r = efi_allocate_pool(EFI_ALLOCATE_ANY_PAGES, buffer_size,
    			      (void **)buffer);
    	if (r != EFI_SUCCESS)
    		goto out;
    	r = efi_locate_handle(search_type, protocol, search_key, &buffer_size,
    			      *buffer);
    	if (r == EFI_SUCCESS)
    
    		*no_handles = buffer_size / sizeof(efi_handle_t);
    
    out:
    	return EFI_EXIT(r);
    
    /*
     * Find an interface implementing a protocol.
     *
     * This function implements the LocateProtocol service.
     * See the Unified Extensible Firmware Interface (UEFI) specification
     * for details.
     *
     * @protocol		GUID of the protocol
     * @registration	registration key passed to the notification function
     * @protocol_interface	interface implementing the protocol
    
    static efi_status_t EFIAPI efi_locate_protocol(const efi_guid_t *protocol,
    
    					       void *registration,
    					       void **protocol_interface)
    {
    
    	struct list_head *lhandle;
    
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    	EFI_ENTRY("%pUl, %p, %p", protocol, registration, protocol_interface);
    
    
    	if (!protocol || !protocol_interface)
    		return EFI_EXIT(EFI_INVALID_PARAMETER);
    
    	list_for_each(lhandle, &efi_obj_list) {
    		struct efi_object *efiobj;
    
    		struct efi_handler *handler;
    
    
    		efiobj = list_entry(lhandle, struct efi_object, link);
    
    
    		ret = efi_search_protocol(efiobj->handle, protocol, &handler);
    		if (ret == EFI_SUCCESS) {
    			*protocol_interface = handler->protocol_interface;
    			return EFI_EXIT(EFI_SUCCESS);
    
    	*protocol_interface = NULL;
    
    
    	return EFI_EXIT(EFI_NOT_FOUND);
    }
    
    
    /*
     * Get the device path and handle of an device implementing a protocol.
     *
     * This function implements the LocateDevicePath service.
     * See the Unified Extensible Firmware Interface (UEFI) specification
     * for details.
     *
     * @protocol		GUID of the protocol
     * @device_path		device path
     * @device		handle of the device
     * @return		status code
     */
    static efi_status_t EFIAPI efi_locate_device_path(
    			const efi_guid_t *protocol,
    			struct efi_device_path **device_path,
    			efi_handle_t *device)
    {
    	struct efi_device_path *dp;
    	size_t i;
    	struct efi_handler *handler;
    	efi_handle_t *handles;
    	size_t len, len_dp;
    	size_t len_best = 0;
    	efi_uintn_t no_handles;
    	u8 *remainder;
    	efi_status_t ret;
    
    	EFI_ENTRY("%pUl, %p, %p", protocol, device_path, device);
    
    	if (!protocol || !device_path || !*device_path || !device) {
    		ret = EFI_INVALID_PARAMETER;
    		goto out;
    	}
    
    	/* Find end of device path */
    	len = efi_dp_size(*device_path);
    
    	/* Get all handles implementing the protocol */
    	ret = EFI_CALL(efi_locate_handle_buffer(BY_PROTOCOL, protocol, NULL,
    						&no_handles, &handles));
    	if (ret != EFI_SUCCESS)
    		goto out;
    
    	for (i = 0; i < no_handles; ++i) {
    		/* Find the device path protocol */
    		ret = efi_search_protocol(handles[i], &efi_guid_device_path,
    					  &handler);
    		if (ret != EFI_SUCCESS)
    			continue;
    		dp = (struct efi_device_path *)handler->protocol_interface;
    		len_dp = efi_dp_size(dp);
    		/*
    		 * This handle can only be a better fit
    		 * if its device path length is longer than the best fit and
    		 * if its device path length is shorter of equal the searched
    		 * device path.
    		 */
    		if (len_dp <= len_best || len_dp > len)
    			continue;
    		/* Check if dp is a subpath of device_path */
    		if (memcmp(*device_path, dp, len_dp))
    			continue;
    		*device = handles[i];
    		len_best = len_dp;
    	}
    	if (len_best) {
    		remainder = (u8 *)*device_path + len_best;
    		*device_path = (struct efi_device_path *)remainder;
    		ret = EFI_SUCCESS;
    	} else {
    		ret = EFI_NOT_FOUND;
    	}
    out:
    	return EFI_EXIT(ret);
    }
    
    
    /*
     * Install multiple protocol interfaces.
     *
     * This function implements the MultipleProtocolInterfaces service.
     * See the Unified Extensible Firmware Interface (UEFI) specification
     * for details.
     *
     * @handle	handle on which the protocol interfaces shall be installed
     * @...		NULL terminated argument list with pairs of protocol GUIDS and
     *		interfaces
     * @return	status code
     */
    
    static efi_status_t EFIAPI efi_install_multiple_protocol_interfaces(
    			void **handle, ...)
    {
    	EFI_ENTRY("%p", handle);
    
    	const efi_guid_t *protocol;
    
    	void *protocol_interface;
    	efi_status_t r = EFI_SUCCESS;
    	int i = 0;
    
    	if (!handle)
    		return EFI_EXIT(EFI_INVALID_PARAMETER);
    
    	va_start(argptr, handle);
    	for (;;) {
    		protocol = va_arg(argptr, efi_guid_t*);
    		if (!protocol)
    			break;
    		protocol_interface = va_arg(argptr, void*);
    
    		r = EFI_CALL(efi_install_protocol_interface(
    						handle, protocol,
    						EFI_NATIVE_INTERFACE,
    						protocol_interface));
    
    		if (r != EFI_SUCCESS)
    			break;
    		i++;
    	}
    	va_end(argptr);
    	if (r == EFI_SUCCESS)
    		return EFI_EXIT(r);
    
    
    	/* If an error occurred undo all changes. */
    
    	va_start(argptr, handle);
    	for (; i; --i) {
    		protocol = va_arg(argptr, efi_guid_t*);
    		protocol_interface = va_arg(argptr, void*);
    
    		EFI_CALL(efi_uninstall_protocol_interface(handle, protocol,
    							  protocol_interface));
    
    /*
     * Uninstall multiple protocol interfaces.
     *
     * This function implements the UninstallMultipleProtocolInterfaces service.
     * See the Unified Extensible Firmware Interface (UEFI) specification
     * for details.
     *
     * @handle	handle from which the protocol interfaces shall be removed
     * @...		NULL terminated argument list with pairs of protocol GUIDS and
     *		interfaces
     * @return	status code
     */
    
    static efi_status_t EFIAPI efi_uninstall_multiple_protocol_interfaces(
    			void *handle, ...)
    {
    	EFI_ENTRY("%p", handle);
    
    
    	va_list argptr;
    	const efi_guid_t *protocol;
    	void *protocol_interface;
    	efi_status_t r = EFI_SUCCESS;
    	size_t i = 0;
    
    	if (!handle)
    		return EFI_EXIT(EFI_INVALID_PARAMETER);
    
    	va_start(argptr, handle);
    	for (;;) {
    		protocol = va_arg(argptr, efi_guid_t*);
    		if (!protocol)
    			break;
    		protocol_interface = va_arg(argptr, void*);
    		r = EFI_CALL(efi_uninstall_protocol_interface(
    						handle, protocol,
    						protocol_interface));
    		if (r != EFI_SUCCESS)
    			break;
    		i++;
    	}
    	va_end(argptr);
    	if (r == EFI_SUCCESS)
    		return EFI_EXIT(r);
    
    	/* If an error occurred undo all changes. */
    	va_start(argptr, handle);
    	for (; i; --i) {
    		protocol = va_arg(argptr, efi_guid_t*);
    		protocol_interface = va_arg(argptr, void*);
    		EFI_CALL(efi_install_protocol_interface(&handle, protocol,
    							EFI_NATIVE_INTERFACE,
    							protocol_interface));
    	}
    	va_end(argptr);
    
    	return EFI_EXIT(r);
    
    /*
     * Calculate cyclic redundancy code.
     *
     * This function implements the CalculateCrc32 service.
     * See the Unified Extensible Firmware Interface (UEFI) specification
     * for details.
     *
     * @data	buffer with data
     * @data_size	size of buffer in bytes
     * @crc32_p	cyclic redundancy code
     * @return	status code
     */
    
    static efi_status_t EFIAPI efi_calculate_crc32(void *data,
    					       unsigned long data_size,
    					       uint32_t *crc32_p)
    {
    	EFI_ENTRY("%p, %ld", data, data_size);
    	*crc32_p = crc32(0, data, data_size);
    	return EFI_EXIT(EFI_SUCCESS);
    }
    
    
    /*
     * Copy memory.
     *
     * This function implements the CopyMem service.
     * See the Unified Extensible Firmware Interface (UEFI) specification
     * for details.
     *
     * @destination		destination of the copy operation
     * @source		source of the copy operation
     * @length		number of bytes to copy
     */
    
    static void EFIAPI efi_copy_mem(void *destination, const void *source,
    				size_t length)
    
    	EFI_ENTRY("%p, %p, %ld", destination, source, (unsigned long)length);
    
    	memcpy(destination, source, length);
    
    /*
     * Fill memory with a byte value.
     *
     * This function implements the SetMem service.
     * See the Unified Extensible Firmware Interface (UEFI) specification
     * for details.
     *
     * @buffer		buffer to fill
     * @size		size of buffer in bytes
     * @value		byte to copy to the buffer
     */
    
    static void EFIAPI efi_set_mem(void *buffer, size_t size, uint8_t value)
    
    	EFI_ENTRY("%p, %ld, 0x%x", buffer, (unsigned long)size, value);
    
    	memset(buffer, value, size);
    
    /*
     * Open protocol interface on a handle.
     *
     * @handler		handler of a protocol
     * @protocol_interface	interface implementing the protocol
     * @agent_handle	handle of the driver
     * @controller_handle	handle of the controller
     * @attributes		attributes indicating how to open the protocol
     * @return		status code
     */
    static efi_status_t efi_protocol_open(
    			struct efi_handler *handler,
    			void **protocol_interface, void *agent_handle,
    			void *controller_handle, uint32_t attributes)
    {
    	struct efi_open_protocol_info_item *item;
    	struct efi_open_protocol_info_entry *match = NULL;
    	bool opened_by_driver = false;
    	bool opened_exclusive = false;
    
    	/* If there is no agent, only return the interface */
    	if (!agent_handle)
    		goto out;
    
    	/* For TEST_PROTOCOL ignore interface attribute */
    	if (attributes != EFI_OPEN_PROTOCOL_TEST_PROTOCOL)
    		*protocol_interface = NULL;
    
    	/*
    	 * Check if the protocol is already opened by a driver with the same
    	 * attributes or opened exclusively
    	 */
    	list_for_each_entry(item, &handler->open_infos, link) {
    		if (item->info.agent_handle == agent_handle) {
    			if ((attributes & EFI_OPEN_PROTOCOL_BY_DRIVER) &&
    			    (item->info.attributes == attributes))
    				return EFI_ALREADY_STARTED;
    		}
    		if (item->info.attributes & EFI_OPEN_PROTOCOL_EXCLUSIVE)
    			opened_exclusive = true;
    	}
    
    	/* Only one controller can open the protocol exclusively */
    	if (opened_exclusive && attributes &
    	    (EFI_OPEN_PROTOCOL_EXCLUSIVE | EFI_OPEN_PROTOCOL_BY_DRIVER))
    		return EFI_ACCESS_DENIED;
    
    	/* Prepare exclusive opening */
    	if (attributes & EFI_OPEN_PROTOCOL_EXCLUSIVE) {
    		/* Try to disconnect controllers */
    		list_for_each_entry(item, &handler->open_infos, link) {
    			if (item->info.attributes ==
    					EFI_OPEN_PROTOCOL_BY_DRIVER)
    				EFI_CALL(efi_disconnect_controller(
    						item->info.controller_handle,
    						item->info.agent_handle,
    						NULL));
    		}
    		opened_by_driver = false;
    		/* Check if all controllers are disconnected */
    		list_for_each_entry(item, &handler->open_infos, link) {
    			if (item->info.attributes & EFI_OPEN_PROTOCOL_BY_DRIVER)
    				opened_by_driver = true;
    		}
    		/* Only one controller can be conncected */
    		if (opened_by_driver)
    			return EFI_ACCESS_DENIED;
    	}
    
    	/* Find existing entry */
    	list_for_each_entry(item, &handler->open_infos, link) {
    		if (item->info.agent_handle == agent_handle &&
    		    item->info.controller_handle == controller_handle)
    			match = &item->info;
    	}
    	/* None found, create one */
    	if (!match) {
    		match = efi_create_open_info(handler);
    		if (!match)
    			return EFI_OUT_OF_RESOURCES;
    	}
    
    	match->agent_handle = agent_handle;
    	match->controller_handle = controller_handle;
    	match->attributes = attributes;
    	match->open_count++;
    
    out:
    	/* For TEST_PROTOCOL ignore interface attribute. */
    	if (attributes != EFI_OPEN_PROTOCOL_TEST_PROTOCOL)
    		*protocol_interface = handler->protocol_interface;
    
    	return EFI_SUCCESS;
    }
    
    
    /*
     * Open protocol interface on a handle.
     *
     * This function implements the OpenProtocol interface.
     * See the Unified Extensible Firmware Interface (UEFI) specification
     * for details.
     *
     * @handle		handle on which the protocol shall be opened
     * @protocol		GUID of the protocol
     * @protocol_interface	interface implementing the protocol
     * @agent_handle	handle of the driver
     * @controller_handle	handle of the controller
     * @attributes		attributes indicating how to open the protocol
     * @return		status code
     */
    
    static efi_status_t EFIAPI efi_open_protocol(
    
    			void *handle, const efi_guid_t *protocol,
    
    			void **protocol_interface, void *agent_handle,
    			void *controller_handle, uint32_t attributes)
    {
    
    	struct efi_handler *handler;
    
    	efi_status_t r = EFI_INVALID_PARAMETER;
    
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    	EFI_ENTRY("%p, %pUl, %p, %p, %p, 0x%x", handle, protocol,
    
    		  protocol_interface, agent_handle, controller_handle,
    		  attributes);
    
    	if (!handle || !protocol ||
    	    (!protocol_interface && attributes !=
    	     EFI_OPEN_PROTOCOL_TEST_PROTOCOL)) {
    		goto out;
    	}
    
    	switch (attributes) {
    	case EFI_OPEN_PROTOCOL_BY_HANDLE_PROTOCOL:
    	case EFI_OPEN_PROTOCOL_GET_PROTOCOL:
    	case EFI_OPEN_PROTOCOL_TEST_PROTOCOL:
    		break;
    	case EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER:
    		if (controller_handle == handle)
    			goto out;
    
    		/* fall-through */
    
    	case EFI_OPEN_PROTOCOL_BY_DRIVER:
    	case EFI_OPEN_PROTOCOL_BY_DRIVER | EFI_OPEN_PROTOCOL_EXCLUSIVE:
    
    		/* Check that the controller handle is valid */
    		if (!efi_search_obj(controller_handle))
    
    		/* fall-through */
    
    	case EFI_OPEN_PROTOCOL_EXCLUSIVE:
    
    		/* Check that the agent handle is valid */
    		if (!efi_search_obj(agent_handle))
    
    	r = efi_search_protocol(handle, protocol, &handler);
    	if (r != EFI_SUCCESS)
    		goto out;
    
    	r = efi_protocol_open(handler, protocol_interface, agent_handle,
    			      controller_handle, attributes);
    
    out:
    	return EFI_EXIT(r);
    }
    
    
    /*
     * Get interface of a protocol on a handle.
     *
     * This function implements the HandleProtocol service.
     * See the Unified Extensible Firmware Interface (UEFI) specification
     * for details.
     *
     * @handle		handle on which the protocol shall be opened
     * @protocol		GUID of the protocol
     * @protocol_interface  interface implementing the protocol
     * @return		status code
     */
    
    static efi_status_t EFIAPI efi_handle_protocol(efi_handle_t handle,
    
    					       const efi_guid_t *protocol,
    
    					       void **protocol_interface)
    {
    
    	return efi_open_protocol(handle, protocol, protocol_interface, NULL,
    				 NULL, EFI_OPEN_PROTOCOL_BY_HANDLE_PROTOCOL);
    
    static efi_status_t efi_bind_controller(
    			efi_handle_t controller_handle,
    			efi_handle_t driver_image_handle,
    			struct efi_device_path *remain_device_path)
    {
    	struct efi_driver_binding_protocol *binding_protocol;
    	efi_status_t r;
    
    	r = EFI_CALL(efi_open_protocol(driver_image_handle,
    				       &efi_guid_driver_binding_protocol,
    				       (void **)&binding_protocol,
    				       driver_image_handle, NULL,
    				       EFI_OPEN_PROTOCOL_GET_PROTOCOL));
    	if (r != EFI_SUCCESS)
    		return r;
    	r = EFI_CALL(binding_protocol->supported(binding_protocol,
    						 controller_handle,
    						 remain_device_path));
    	if (r == EFI_SUCCESS)
    		r = EFI_CALL(binding_protocol->start(binding_protocol,
    						     controller_handle,
    						     remain_device_path));
    	EFI_CALL(efi_close_protocol(driver_image_handle,
    				    &efi_guid_driver_binding_protocol,
    				    driver_image_handle, NULL));
    	return r;
    }
    
    static efi_status_t efi_connect_single_controller(
    			efi_handle_t controller_handle,
    			efi_handle_t *driver_image_handle,
    			struct efi_device_path *remain_device_path)
    {
    	efi_handle_t *buffer;
    	size_t count;
    	size_t i;
    	efi_status_t r;
    	size_t connected = 0;
    
    	/* Get buffer with all handles with driver binding protocol */
    	r = EFI_CALL(efi_locate_handle_buffer(BY_PROTOCOL,
    					      &efi_guid_driver_binding_protocol,
    					      NULL, &count, &buffer));
    	if (r != EFI_SUCCESS)
    		return r;
    
    	/*  Context Override */
    	if (driver_image_handle) {
    		for (; *driver_image_handle; ++driver_image_handle) {
    			for (i = 0; i < count; ++i) {
    				if (buffer[i] == *driver_image_handle) {
    					buffer[i] = NULL;
    					r = efi_bind_controller(
    							controller_handle,
    							*driver_image_handle,
    							remain_device_path);
    					/*
    					 * For drivers that do not support the
    					 * controller or are already connected
    					 * we receive an error code here.
    					 */
    					if (r == EFI_SUCCESS)
    						++connected;
    				}
    			}
    		}
    	}
    
    	/*
    	 * TODO: Some overrides are not yet implemented:
    	 * - Platform Driver Override
    	 * - Driver Family Override Search
    	 * - Bus Specific Driver Override
    	 */
    
    	/* Driver Binding Search */
    	for (i = 0; i < count; ++i) {
    		if (buffer[i]) {
    			r = efi_bind_controller(controller_handle,
    						buffer[i],
    						remain_device_path);
    			if (r == EFI_SUCCESS)
    				++connected;
    		}
    	}
    
    	efi_free_pool(buffer);
    	if (!connected)
    		return EFI_NOT_FOUND;
    	return EFI_SUCCESS;
    }
    
    /*
     * Connect a controller to a driver.
     *
     * This function implements the ConnectController service.
     * See the Unified Extensible Firmware Interface (UEFI) specification
     * for details.
     *
     * First all driver binding protocol handles are tried for binding drivers.
     * Afterwards all handles that have openened a protocol of the controller
     * with EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER are connected to drivers.
     *
     * @controller_handle	handle of the controller
     * @driver_image_handle	handle of the driver
     * @remain_device_path	device path of a child controller
     * @recursive		true to connect all child controllers
     * @return		status code
     */
    static efi_status_t EFIAPI efi_connect_controller(
    			efi_handle_t controller_handle,
    			efi_handle_t *driver_image_handle,
    			struct efi_device_path *remain_device_path,
    			bool recursive)
    {
    	efi_status_t r;
    	efi_status_t ret = EFI_NOT_FOUND;
    	struct efi_object *efiobj;
    
    	EFI_ENTRY("%p, %p, %p, %d", controller_handle, driver_image_handle,
    		  remain_device_path, recursive);
    
    	efiobj = efi_search_obj(controller_handle);
    	if (!efiobj) {
    		ret = EFI_INVALID_PARAMETER;
    		goto out;
    	}
    
    	r = efi_connect_single_controller(controller_handle,
    					  driver_image_handle,
    					  remain_device_path);
    	if (r == EFI_SUCCESS)
    		ret = EFI_SUCCESS;
    	if (recursive) {
    		struct efi_handler *handler;
    		struct efi_open_protocol_info_item *item;
    
    		list_for_each_entry(handler, &efiobj->protocols, link) {
    			list_for_each_entry(item, &handler->open_infos, link) {
    				if (item->info.attributes &
    				    EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER) {
    					r = EFI_CALL(efi_connect_controller(
    						item->info.controller_handle,
    						driver_image_handle,
    						remain_device_path,
    						recursive));
    					if (r == EFI_SUCCESS)
    						ret = EFI_SUCCESS;
    				}
    			}
    		}
    	}
    	/*  Check for child controller specified by end node */
    	if (ret != EFI_SUCCESS && remain_device_path &&
    	    remain_device_path->type == DEVICE_PATH_TYPE_END)
    		ret = EFI_SUCCESS;
    out:
    	return EFI_EXIT(ret);
    }
    
    
    /*
     * Get all child controllers associated to a driver.
     * The allocated buffer has to be freed with free().
     *
     * @efiobj			handle of the controller
     * @driver_handle		handle of the driver
     * @number_of_children		number of child controllers
     * @child_handle_buffer		handles of the the child controllers
     */
    static efi_status_t efi_get_child_controllers(
    				struct efi_object *efiobj,
    				efi_handle_t driver_handle,
    				efi_uintn_t *number_of_children,
    				efi_handle_t **child_handle_buffer)
    {
    	struct efi_handler *handler;
    	struct efi_open_protocol_info_item *item;
    	efi_uintn_t count = 0, i;
    	bool duplicate;
    
    	/* Count all child controller associations */
    	list_for_each_entry(handler, &efiobj->protocols, link) {
    		list_for_each_entry(item, &handler->open_infos, link) {
    			if (item->info.agent_handle == driver_handle &&
    			    item->info.attributes &
    			    EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER)
    				++count;
    		}
    	}
    	/*
    	 * Create buffer. In case of duplicate child controller assignments
    	 * the buffer will be too large. But that does not harm.
    	 */
    	*number_of_children = 0;
    	*child_handle_buffer = calloc(count, sizeof(efi_handle_t));
    	if (!*child_handle_buffer)
    		return EFI_OUT_OF_RESOURCES;
    	/* Copy unique child handles */
    	list_for_each_entry(handler, &efiobj->protocols, link) {
    		list_for_each_entry(item, &handler->open_infos, link) {
    			if (item->info.agent_handle == driver_handle &&
    			    item->info.attributes &
    			    EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER) {
    				/* Check this is a new child controller */
    				duplicate = false;
    				for (i = 0; i < *number_of_children; ++i) {
    					if ((*child_handle_buffer)[i] ==
    					    item->info.controller_handle)
    						duplicate = true;
    				}
    				/* Copy handle to buffer */
    				if (!duplicate) {
    					i = (*number_of_children)++;
    					(*child_handle_buffer)[i] =
    						item->info.controller_handle;
    				}
    			}
    		}
    	}
    	return EFI_SUCCESS;
    }
    
    /*
     * Disconnect a controller from a driver.
     *
     * This function implements the DisconnectController service.
     * See the Unified Extensible Firmware Interface (UEFI) specification
     * for details.
     *
     * @controller_handle	handle of the controller
     * @driver_image_handle handle of the driver
     * @child_handle	handle of the child to destroy
     * @return		status code
     */
    static efi_status_t EFIAPI efi_disconnect_controller(
    				efi_handle_t controller_handle,
    				efi_handle_t driver_image_handle,
    				efi_handle_t child_handle)
    {
    	struct efi_driver_binding_protocol *binding_protocol;
    	efi_handle_t *child_handle_buffer = NULL;
    	size_t number_of_children = 0;
    	efi_status_t r;
    	size_t stop_count = 0;
    	struct efi_object *efiobj;
    
    	EFI_ENTRY("%p, %p, %p", controller_handle, driver_image_handle,
    		  child_handle);
    
    	efiobj = efi_search_obj(controller_handle);
    	if (!efiobj) {
    		r = EFI_INVALID_PARAMETER;
    		goto out;
    	}
    
    	if (child_handle && !efi_search_obj(child_handle)) {
    		r = EFI_INVALID_PARAMETER;
    		goto out;
    	}
    
    	/* If no driver handle is supplied, disconnect all drivers */
    	if (!driver_image_handle) {
    		r = efi_disconnect_all_drivers(efiobj, NULL, child_handle);
    		goto out;
    	}
    
    	/* Create list of child handles */
    	if (child_handle) {
    		number_of_children = 1;
    		child_handle_buffer = &child_handle;
    	} else {
    		efi_get_child_controllers(efiobj,
    					  driver_image_handle,
    					  &number_of_children,
    					  &child_handle_buffer);
    	}
    
    	/* Get the driver binding protocol */
    	r = EFI_CALL(efi_open_protocol(driver_image_handle,
    				       &efi_guid_driver_binding_protocol,
    				       (void **)&binding_protocol,
    				       driver_image_handle, NULL,
    				       EFI_OPEN_PROTOCOL_GET_PROTOCOL));
    	if (r != EFI_SUCCESS)
    		goto out;
    	/* Remove the children */
    	if (number_of_children) {
    		r = EFI_CALL(binding_protocol->stop(binding_protocol,
    						    controller_handle,
    						    number_of_children,
    						    child_handle_buffer));
    		if (r == EFI_SUCCESS)
    			++stop_count;
    	}
    	/* Remove the driver */
    	if (!child_handle)
    		r = EFI_CALL(binding_protocol->stop(binding_protocol,
    						    controller_handle,
    						    0, NULL));
    	if (r == EFI_SUCCESS)
    		++stop_count;
    	EFI_CALL(efi_close_protocol(driver_image_handle,
    				    &efi_guid_driver_binding_protocol,
    				    driver_image_handle, NULL));
    
    	if (stop_count)
    		r = EFI_SUCCESS;
    	else
    		r = EFI_NOT_FOUND;
    out:
    	if (!child_handle)
    		free(child_handle_buffer);
    	return EFI_EXIT(r);
    }
    
    
    static const struct efi_boot_services efi_boot_services = {
    	.hdr = {
    		.headersize = sizeof(struct efi_table_hdr),
    	},
    	.raise_tpl = efi_raise_tpl,
    	.restore_tpl = efi_restore_tpl,
    	.allocate_pages = efi_allocate_pages_ext,
    	.free_pages = efi_free_pages_ext,
    	.get_memory_map = efi_get_memory_map_ext,
    
    	.allocate_pool = efi_allocate_pool_ext,
    
    	.free_pool = efi_free_pool_ext,
    
    	.create_event = efi_create_event_ext,
    
    	.set_timer = efi_set_timer_ext,
    
    	.wait_for_event = efi_wait_for_event,
    
    	.signal_event = efi_signal_event_ext,
    
    	.close_event = efi_close_event,
    	.check_event = efi_check_event,
    
    	.install_protocol_interface = efi_install_protocol_interface,
    
    	.reinstall_protocol_interface = efi_reinstall_protocol_interface,
    
    	.uninstall_protocol_interface = efi_uninstall_protocol_interface,
    
    	.handle_protocol = efi_handle_protocol,
    	.reserved = NULL,
    	.register_protocol_notify = efi_register_protocol_notify,
    
    	.locate_handle = efi_locate_handle_ext,
    
    	.locate_device_path = efi_locate_device_path,
    
    	.install_configuration_table = efi_install_configuration_table_ext,
    
    	.load_image = efi_load_image,
    	.start_image = efi_start_image,
    
    	.exit = efi_exit,
    
    	.unload_image = efi_unload_image,
    	.exit_boot_services = efi_exit_boot_services,
    	.get_next_monotonic_count = efi_get_next_monotonic_count,
    	.stall = efi_stall,
    	.set_watchdog_timer = efi_set_watchdog_timer,
    	.connect_controller = efi_connect_controller,
    	.disconnect_controller = efi_disconnect_controller,
    	.open_protocol = efi_open_protocol,
    	.close_protocol = efi_close_protocol,
    	.open_protocol_information = efi_open_protocol_information,
    	.protocols_per_handle = efi_protocols_per_handle,
    	.locate_handle_buffer = efi_locate_handle_buffer,
    	.locate_protocol = efi_locate_protocol,
    	.install_multiple_protocol_interfaces = efi_install_multiple_protocol_interfaces,
    	.uninstall_multiple_protocol_interfaces = efi_uninstall_multiple_protocol_interfaces,
    	.calculate_crc32 = efi_calculate_crc32,
    	.copy_mem = efi_copy_mem,
    	.set_mem = efi_set_mem,
    
    	.create_event_ex = efi_create_event_ex,
    
    static uint16_t __efi_runtime_data firmware_vendor[] = L"Das U-Boot";
    
    struct efi_system_table __efi_runtime_data systab = {
    
    	.hdr = {
    		.signature = EFI_SYSTEM_TABLE_SIGNATURE,
    
    		.revision = 2 << 16 | 70, /* 2.7 */
    
    		.headersize = sizeof(struct efi_table_hdr),
    	},
    	.fw_vendor = (long)firmware_vendor,
    	.con_in = (void*)&efi_con_in,
    	.con_out = (void*)&efi_con_out,
    	.std_err = (void*)&efi_con_out,
    	.runtime = (void*)&efi_runtime_services,
    	.boottime = (void*)&efi_boot_services,
    	.nr_tables = 0,
    	.tables = (void*)efi_conf_table,
    };