Re: [RFT PATCH] EmbeddedPkg/AndroidFastbootApp: remove dependency on deprecated BdsLib

[Ard Biesheuvel <ard.biesheuvel@linaro.org>]

On 10 April 2017 at 17:55, Ard Biesheuvel <ard.biesheuvel@linaro.org> wrote:
> One of the last remaining modules with a dependency on the deprecated
> BdsLib implementation from ArmPkg is the Android fastboot application.
>
> Its only dependency on BdsLib is BdsStartEfiApplication(), which is
> used in the most peculiar way: the fastboot app loads the kernel image
> into memory, and creates a MemoryMapped() device path for it. It then
> proceeds and calls BdsStartEfiApplication(), which explicitly loads the
> contents of the devicepath into memory, creating a second in-memory copy
> of the kernel image, after which it invokes gBS->LoadImage() with a
> buffer address and size (while it is perfectly capable of loading from
> a devicepath directly)
>
> Since we know the device path is fully qualified and connected, and does
> not require any of the additional processing that BdsStartEfiApplication()
> does when dereferencing a device path, we should be able to pass this
> devicepath into LoadImage() directly.
>
> So create a simplified local clone of BdsStartEfiApplication(), and drop
> the dependency on BdsLib.
>
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

Should we just merge this and see what happens?


> ---
>  EmbeddedPkg/Application/AndroidFastboot/AndroidFastbootApp.inf   |  2 +-
>  EmbeddedPkg/Application/AndroidFastboot/Arm/BootAndroidBootImg.c | 57 +++++++++++++++++++-
>  2 files changed, 57 insertions(+), 2 deletions(-)
>
> diff --git a/EmbeddedPkg/Application/AndroidFastboot/AndroidFastbootApp.inf b/EmbeddedPkg/Application/AndroidFastboot/AndroidFastbootApp.inf
> index 3e115171ce01..8d2b23c6f8b8 100644
> --- a/EmbeddedPkg/Application/AndroidFastboot/AndroidFastbootApp.inf
> +++ b/EmbeddedPkg/Application/AndroidFastboot/AndroidFastbootApp.inf
> @@ -30,7 +30,6 @@ [Sources.ARM, Sources.AARCH64]
>  [LibraryClasses]
>    BaseLib
>    BaseMemoryLib
> -  BdsLib
>    DebugLib
>    DevicePathLib
>    DxeServicesTableLib
> @@ -45,6 +44,7 @@ [LibraryClasses]
>  [Protocols]
>    gAndroidFastbootTransportProtocolGuid
>    gAndroidFastbootPlatformProtocolGuid
> +  gEfiLoadedImageProtocolGuid
>    gEfiSimpleTextOutProtocolGuid
>    gEfiSimpleTextInProtocolGuid
>
> diff --git a/EmbeddedPkg/Application/AndroidFastboot/Arm/BootAndroidBootImg.c b/EmbeddedPkg/Application/AndroidFastboot/Arm/BootAndroidBootImg.c
> index 46a7ceb3a41c..f446cce2855a 100644
> --- a/EmbeddedPkg/Application/AndroidFastboot/Arm/BootAndroidBootImg.c
> +++ b/EmbeddedPkg/Application/AndroidFastboot/Arm/BootAndroidBootImg.c
> @@ -15,6 +15,7 @@
>  #include "AndroidFastbootApp.h"
>
>  #include <Protocol/DevicePath.h>
> +#include <Protocol/LoadedImage.h>
>
>  #include <Library/BdsLib.h>
>  #include <Library/DevicePathLib.h>
> @@ -50,6 +51,60 @@ STATIC CONST MEMORY_DEVICE_PATH MemoryDevicePathTemplate =
>    } // End
>  };
>
> +
> +/**
> +  Start an EFI Application from a Device Path
> +
> +  @param  ParentImageHandle     Handle of the calling image
> +  @param  DevicePath            Location of the EFI Application
> +
> +  @retval EFI_SUCCESS           All drivers have been connected
> +  @retval EFI_NOT_FOUND         The Linux kernel Device Path has not been found
> +  @retval EFI_OUT_OF_RESOURCES  There is not enough resource memory to store the matching results.
> +
> +**/
> +STATIC
> +EFI_STATUS
> +StartEfiApplication (
> +  IN EFI_HANDLE                  ParentImageHandle,
> +  IN EFI_DEVICE_PATH_PROTOCOL    *DevicePath,
> +  IN UINTN                       LoadOptionsSize,
> +  IN VOID*                       LoadOptions
> +  )
> +{
> +  EFI_STATUS                   Status;
> +  EFI_HANDLE                   ImageHandle;
> +  EFI_LOADED_IMAGE_PROTOCOL*   LoadedImage;
> +
> +  // Load the image from the device path with Boot Services function
> +  Status = gBS->LoadImage (TRUE, ParentImageHandle, DevicePath, NULL, 0,
> +                  &ImageHandle);
> +  if (EFI_ERROR (Status)) {
> +    return Status;
> +  }
> +
> +  // Passed LoadOptions to the EFI Application
> +  if (LoadOptionsSize != 0) {
> +    Status = gBS->HandleProtocol (ImageHandle, &gEfiLoadedImageProtocolGuid,
> +                    (VOID **) &LoadedImage);
> +    if (EFI_ERROR (Status)) {
> +      return Status;
> +    }
> +
> +    LoadedImage->LoadOptionsSize  = LoadOptionsSize;
> +    LoadedImage->LoadOptions      = LoadOptions;
> +  }
> +
> +  // Before calling the image, enable the Watchdog Timer for  the 5 Minute period
> +  gBS->SetWatchdogTimer (5 * 60, 0x0000, 0x00, NULL);
> +  // Start the image
> +  Status = gBS->StartImage (ImageHandle, NULL, NULL);
> +  // Clear the Watchdog Timer after the image returns
> +  gBS->SetWatchdogTimer (0x0000, 0x0000, 0x0000, NULL);
> +
> +  return Status;
> +}
> +
>  EFI_STATUS
>  BootAndroidBootImg (
>    IN UINTN    BufferSize,
> @@ -100,7 +155,7 @@ BootAndroidBootImg (
>      LoadOptions = NewLoadOptions;
>    }
>
> -  Status = BdsStartEfiApplication (gImageHandle,
> +  Status = StartEfiApplication (gImageHandle,
>               (EFI_DEVICE_PATH_PROTOCOL *) &KernelDevicePath,
>               StrSize (LoadOptions),
>               LoadOptions);
> --
> 2.9.3
>