Re: [PATCH v3 08/23] OvmfPkg/Virtio10Dxe: add the RingBaseShift offset

[Laszlo Ersek <lersek@redhat.com>]

On 08/23/17 14:22, Brijesh Singh wrote:
> virtio drivers use VIRTIO_DEVICE_PROTOCOL.MapSharedBuffer() to map the
> ring buffer host address to a device address. If an IOMMU is present then
> RingBaseShift contains the offset from the host address.
> 
> 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/Virtio10Dxe/Virtio10.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)

Reviewed-by: Laszlo Ersek <lersek@redhat.com>

Thanks!
Laszlo

> diff --git a/OvmfPkg/Virtio10Dxe/Virtio10.c b/OvmfPkg/Virtio10Dxe/Virtio10.c
> index ef9a00710668..e9b50b6e437b 100644
> --- a/OvmfPkg/Virtio10Dxe/Virtio10.c
> +++ b/OvmfPkg/Virtio10Dxe/Virtio10.c
> @@ -498,11 +498,10 @@ Virtio10SetQueueAddress (
>    UINT64         Address;
>    UINT16         Enable;
>  
> -  ASSERT (RingBaseShift == 0);
> -
>    Dev = VIRTIO_1_0_FROM_VIRTIO_DEVICE (This);
>  
>    Address = (UINTN)Ring->Desc;
> +  Address += RingBaseShift;
>    Status = Virtio10Transfer (Dev->PciIo, &Dev->CommonConfig, TRUE,
>               OFFSET_OF (VIRTIO_PCI_COMMON_CFG, QueueDesc),
>               sizeof Address, &Address);
> @@ -511,6 +510,7 @@ Virtio10SetQueueAddress (
>    }
>  
>    Address = (UINTN)Ring->Avail.Flags;
> +  Address += RingBaseShift;
>    Status = Virtio10Transfer (Dev->PciIo, &Dev->CommonConfig, TRUE,
>               OFFSET_OF (VIRTIO_PCI_COMMON_CFG, QueueAvail),
>               sizeof Address, &Address);
> @@ -519,6 +519,7 @@ Virtio10SetQueueAddress (
>    }
>  
>    Address = (UINTN)Ring->Used.Flags;
> +  Address += RingBaseShift;
>    Status = Virtio10Transfer (Dev->PciIo, &Dev->CommonConfig, TRUE,
>               OFFSET_OF (VIRTIO_PCI_COMMON_CFG, QueueUsed),
>               sizeof Address, &Address);
>