Re: [PATCH v2 08/23] OvmfPkg/VirtioPciDeviceDxe: implement IOMMU-like member functions

[Laszlo Ersek <lersek@redhat.com>]

On 08/14/17 13:36, Brijesh Singh wrote:
> The patch implements the newly added IOMMU-like member functions by
> respectively delegating the job to:
> 
> - VIRTIO_DEVICE_PROTOCOL.AllocateSharedPages () ->
>     MemoryAllocationLib.AllocatePages()
> 
> - VIRTIO_DEVICE_PROTOCOL.FreeSharedPages () ->
>     MemoryAllocationLib.FreePages ()
> 
> - VIRTIO_DEVICE_PROTOCOL.MapSharedBuffer () -> no-op
> 
> - VIRTIO_DEVICE_PROTOCOL.UnmapSharedBuffer () -> no-op
> 
> Suggested-by: Laszlo Ersek <lersek@redhat.com>
> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> Cc: Jordan Justen <jordan.l.justen@intel.com>
> Cc: Tom Lendacky <thomas.lendacky@amd.com>
> Cc: Laszlo Ersek <lersek@redhat.com>
> Contributed-under: TianoCore Contribution Agreement 1.1
> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
> ---
>  OvmfPkg/VirtioPciDeviceDxe/VirtioPciDevice.h    | 34 ++++++++++++
>  OvmfPkg/VirtioPciDeviceDxe/VirtioPciDevice.c    |  7 ++-
>  OvmfPkg/VirtioPciDeviceDxe/VirtioPciFunctions.c | 58 ++++++++++++++++++++
>  3 files changed, 98 insertions(+), 1 deletion(-)
> 
> diff --git a/OvmfPkg/VirtioPciDeviceDxe/VirtioPciDevice.h b/OvmfPkg/VirtioPciDeviceDxe/VirtioPciDevice.h
> index 6f51f816ef0f..41df5a98e560 100644
> --- a/OvmfPkg/VirtioPciDeviceDxe/VirtioPciDevice.h
> +++ b/OvmfPkg/VirtioPciDeviceDxe/VirtioPciDevice.h
> @@ -3,6 +3,7 @@
>    Internal definitions for the VirtIo PCI Device driver
>  
>    Copyright (C) 2013, ARM Ltd
> +  Copyright (c) 2017, AMD Inc, All rights reserved.<BR>
>  
>    This program and the accompanying materials are licensed and made available
>    under the terms and conditions of the BSD License which accompanies this
> @@ -156,4 +157,37 @@ VirtioPciSetDeviceStatus (
>    IN  UINT8                          DeviceStatus
>    );
>  
> +EFI_STATUS
> +EFIAPI
> +VirtioPciAllocateSharedPages (
> +  IN  VIRTIO_DEVICE_PROTOCOL        *This,
> +  IN  UINTN                         NumPages,
> +  OUT VOID                          **HostAddress
> +  );
> +
> +VOID
> +EFIAPI
> +VirtioPciFreeSharedPages (
> +  IN  VIRTIO_DEVICE_PROTOCOL        *This,
> +  IN  UINTN                         NumPages,
> +  IN  VOID                          *HostAddress
> +  );
> +
> +EFI_STATUS
> +EFIAPI
> +VirtioPciMapSharedBuffer (
> +  IN      VIRTIO_DEVICE_PROTOCOL        *This,
> +  IN      VIRTIO_MAP_OPERATION          Operation,
> +  IN      VOID                          *HostAddress,
> +  IN OUT  UINTN                         *NumberOfBytes,
> +  OUT     EFI_PHYSICAL_ADDRESS          *DeviceAddress,
> +  OUT     VOID                          **Mapping
> +  );
> +
> +EFI_STATUS
> +EFIAPI
> +VirtioPciUnmapSharedBuffer (
> +  IN  VIRTIO_DEVICE_PROTOCOL        *This,
> +  IN  VOID                          *Mapping
> +  );
>  #endif // _VIRTIO_PCI_DEVICE_DXE_H_
> diff --git a/OvmfPkg/VirtioPciDeviceDxe/VirtioPciDevice.c b/OvmfPkg/VirtioPciDeviceDxe/VirtioPciDevice.c
> index e41730456471..b847f3c02528 100644
> --- a/OvmfPkg/VirtioPciDeviceDxe/VirtioPciDevice.c
> +++ b/OvmfPkg/VirtioPciDeviceDxe/VirtioPciDevice.c
> @@ -5,6 +5,7 @@
>    Copyright (C) 2012, Red Hat, Inc.
>    Copyright (c) 2012 - 2016, Intel Corporation. All rights reserved.<BR>
>    Copyright (C) 2013, ARM Ltd.
> +  Copyright (C) 2017, AMD Inc, All rights reserved.<BR>
>  
>    This program and the accompanying materials are licensed and made available
>    under the terms and conditions of the BSD License which accompanies this
> @@ -40,7 +41,11 @@ STATIC VIRTIO_DEVICE_PROTOCOL mDeviceProtocolTemplate = {
>    VirtioPciGetDeviceStatus,             // GetDeviceStatus
>    VirtioPciSetDeviceStatus,             // SetDeviceStatus
>    VirtioPciDeviceWrite,                 // WriteDevice
> -  VirtioPciDeviceRead                   // ReadDevice
> +  VirtioPciDeviceRead,                  // ReadDevice
> +  VirtioPciAllocateSharedPages,         // AllocateSharedPages
> +  VirtioPciFreeSharedPages,             // FreeSharedPages
> +  VirtioPciMapSharedBuffer,             // MapSharedBuffer
> +  VirtioPciUnmapSharedBuffer,           // UnmapSharedBuffer
>  };
>  
>  /**
> diff --git a/OvmfPkg/VirtioPciDeviceDxe/VirtioPciFunctions.c b/OvmfPkg/VirtioPciDeviceDxe/VirtioPciFunctions.c
> index 5f86914265ea..4597095deb78 100644
> --- a/OvmfPkg/VirtioPciDeviceDxe/VirtioPciFunctions.c
> +++ b/OvmfPkg/VirtioPciDeviceDxe/VirtioPciFunctions.c
> @@ -5,6 +5,7 @@
>    Copyright (C) 2012, Red Hat, Inc.
>    Copyright (c) 2012, Intel Corporation. All rights reserved.<BR>
>    Copyright (C) 2013, ARM Ltd.
> +  Copyright (C) 2017, AMD Inc, All rights reserved.<BR>
>  
>    This program and the accompanying materials are licensed and made available
>    under the terms and conditions of the BSD License which accompanies this
> @@ -271,3 +272,60 @@ VirtioPciSetDeviceStatus (
>    return VirtioPciIoWrite (Dev, VIRTIO_PCI_OFFSET_QUEUE_DEVICE_STATUS,
>        sizeof (UINT8), DeviceStatus);
>  }
> +
> +EFI_STATUS
> +EFIAPI
> +VirtioPciAllocateSharedPages (
> +  IN  VIRTIO_DEVICE_PROTOCOL  *This,
> +  IN  UINTN                   NumPages,
> +  OUT VOID                    **HostAddress
> +  )
> +{
> +  VOID        *Buffer;
> +
> +  Buffer = AllocatePages (NumPages);
> +  if (Buffer == NULL) {
> +    return EFI_OUT_OF_RESOURCES;
> +  }
> +
> +  *HostAddress = Buffer;
> +  return EFI_SUCCESS;
> +}
> +
> +VOID
> +EFIAPI
> +VirtioPciFreeSharedPages (
> +  IN  VIRTIO_DEVICE_PROTOCOL  *This,
> +  IN  UINTN                   NumPages,
> +  IN  VOID                    *HostAddress
> +  )
> +{
> +  FreePages (HostAddress, NumPages);
> +}
> +
> +EFI_STATUS
> +EFIAPI
> +VirtioPciMapSharedBuffer (
> +  IN      VIRTIO_DEVICE_PROTOCOL  *This,
> +  IN      VIRTIO_MAP_OPERATION    Operation,
> +  IN      VOID                    *HostAddress,
> +  IN OUT  UINTN                   *NumberOfBytes,
> +  OUT     EFI_PHYSICAL_ADDRESS    *DeviceAddress,
> +  OUT     VOID                    **Mapping
> +  )
> +{
> +  *DeviceAddress = (EFI_PHYSICAL_ADDRESS) (UINTN) HostAddress;
> +  *Mapping = NULL;
> +
> +  return EFI_SUCCESS;
> +}
> +
> +EFI_STATUS
> +EFIAPI
> +VirtioPciUnmapSharedBuffer (
> +  IN  VIRTIO_DEVICE_PROTOCOL    *This,
> +  OUT VOID                      *Mapping
> +  )

(1) Is this an Easter egg for your reviewer? :) "Mapping" should be IN,
not OUT.

This oversight is surprising -- or, well, an Easter egg :) -- because
the function declaration, in
"OvmfPkg/VirtioPciDeviceDxe/VirtioPciDevice.h" above, is correct.

The patch is good otherwise.

Thanks!
Laszlo



> +{
> +  return EFI_SUCCESS;
> +}
>