[U-Boot] [RFC v2 01/11] efi_loader: boottime: add loaded image device path protocol to image handle

[Heinrich Schuchardt]

On 3/27/19 5:40 AM, AKASHI Takahiro wrote:
> To meet UEFI spec v2.7a section 9.2, we should add
> EFI_LOADED_IMAGE_DEVICE_PATH_PROTOCOL to image handle,
> instead of EFI_DEVICE_PATH_PROTOCOL.
>
> Signed-off-by: AKASHI Takahiro <takahiro.akashi at linaro.org>
> ---
>  include/efi_api.h                 |  4 ++++
>  include/efi_loader.h              |  1 +
>  lib/efi_loader/efi_boottime.c     | 19 ++++++++++++-------
>  lib/efi_loader/efi_image_loader.c |  2 ++
>  4 files changed, 19 insertions(+), 7 deletions(-)
>
> diff --git a/include/efi_api.h b/include/efi_api.h
> index ccf608653d4a..63b703c951a7 100644
> --- a/include/efi_api.h
> +++ b/include/efi_api.h
> @@ -333,6 +333,10 @@ struct efi_system_table {
>  	EFI_GUID(0x5b1b31a1, 0x9562, 0x11d2, \
>  		 0x8e, 0x3f, 0x00, 0xa0, 0xc9, 0x69, 0x72, 0x3b)
>
> +#define LOADED_IMAGE_DEVICE_PATH_GUID \
> +	EFI_GUID(0xbc62157e, 0x3e33, 0x4fec, \
> +		 0x99, 0x20, 0x2d, 0x3b, 0x36, 0xd7, 0x50, 0xdf)
> +
>  #define EFI_LOADED_IMAGE_PROTOCOL_REVISION 0x1000
>
>  struct efi_loaded_image {
> diff --git a/include/efi_loader.h b/include/efi_loader.h
> index 512880ab8fbf..3f54e354bdcd 100644
> --- a/include/efi_loader.h
> +++ b/include/efi_loader.h
> @@ -135,6 +135,7 @@ extern const efi_guid_t efi_guid_event_group_reset_system;
>  /* GUID of the device tree table */
>  extern const efi_guid_t efi_guid_fdt;
>  extern const efi_guid_t efi_guid_loaded_image;
> +extern const efi_guid_t efi_guid_loaded_image_device_path;
>  extern const efi_guid_t efi_guid_device_path_to_text_protocol;
>  extern const efi_guid_t efi_simple_file_system_protocol_guid;
>  extern const efi_guid_t efi_file_info_guid;
> diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c
> index 391681260c27..578b32a05ffd 100644
> --- a/lib/efi_loader/efi_boottime.c
> +++ b/lib/efi_loader/efi_boottime.c
> @@ -1519,6 +1519,7 @@ efi_status_t efi_setup_loaded_image(struct efi_device_path *device_path,
>  	efi_status_t ret;
>  	struct efi_loaded_image *info = NULL;
>  	struct efi_loaded_image_obj *obj = NULL;
> +	struct efi_device_path *dp;
>
>  	/* In case of EFI_OUT_OF_RESOURCES avoid illegal free by caller. */
>  	*handle_ptr = NULL;
> @@ -1542,15 +1543,19 @@ efi_status_t efi_setup_loaded_image(struct efi_device_path *device_path,
>
>  	if (device_path) {
>  		info->device_handle = efi_dp_find_obj(device_path, NULL);
> -		/*
> -		 * When asking for the device path interface, return
> -		 * bootefi_device_path
> -		 */
> -		ret = efi_add_protocol(&obj->header,
> -				       &efi_guid_device_path, device_path);
> -		if (ret != EFI_SUCCESS)
> +
> +		dp = efi_dp_append(device_path, file_path);

I think we should pass the original device_path as a parameter to
efi_setup_loaded_image instead of first splitting and then recombining
devicepath elements.

But let's leave this as a TODO after the rest of the refactoring.

> +		if (!dp) {
> +			ret = EFI_OUT_OF_RESOURCES;
>  			goto failure;
> +		}
> +	} else {
> +		dp = NULL;
>  	}
> +	ret = efi_add_protocol(&obj->header,
> +			       &efi_guid_loaded_image_device_path, dp);

I wondered about the loaded imaged device path protocol possibly being
NULL. But the spec explicitely states:

It is legal to call LoadImage() for a buffer in memory with a NULL
DevicePath parameter. In this case, the Loaded Image Device Path
Protocol is installed with a NULL interface pointer.

Reviewed-by: Heinrich Schuchardt <xypron.glpk at gmx.de>

> +	if (ret != EFI_SUCCESS)
> +		goto failure;
>
>  	/*
>  	 * When asking for the loaded_image interface, just
> diff --git a/lib/efi_loader/efi_image_loader.c b/lib/efi_loader/efi_image_loader.c
> index fe66e7b9ffe1..c6177b9ff832 100644
> --- a/lib/efi_loader/efi_image_loader.c
> +++ b/lib/efi_loader/efi_image_loader.c
> @@ -14,6 +14,8 @@
>  const efi_guid_t efi_global_variable_guid = EFI_GLOBAL_VARIABLE_GUID;
>  const efi_guid_t efi_guid_device_path = DEVICE_PATH_GUID;
>  const efi_guid_t efi_guid_loaded_image = LOADED_IMAGE_GUID;
> +const efi_guid_t efi_guid_loaded_image_device_path
> +		= LOADED_IMAGE_DEVICE_PATH_GUID;
>  const efi_guid_t efi_simple_file_system_protocol_guid =
>  		EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID;
>  const efi_guid_t efi_file_info_guid = EFI_FILE_INFO_GUID;
>