Re: [PATCH 2/2] Rework network settings copy code.

[Paul Durrant <xadimgnik@xxxxxxxxx>]

On 22/09/2022 07:58, Owen Smith wrote:
> Rather than copying network settings twice (once on save and once on restore),
> stash the current network interface guid and network Luid on save and copy
> settings from the previous to the new location on restore.
> By relying on the current settings, the copy code will always restore the
> settings that are current. This will pick up any changes that are made without
> requiring a copy from the save.
>
> Signed-off-by: Owen Smith <owen.smith@xxxxxxxxxx>
Acked-by: Paul Durrant <paul@xxxxxxx>

...with one nit...

> ---
>   src/xenvif/pdo.c      |  93 +++--
>   src/xenvif/settings.c | 810 +++++++++++++++++++++++-------------------
>   2 files changed, 508 insertions(+), 395 deletions(-)
>
> diff --git a/src/xenvif/pdo.c b/src/xenvif/pdo.c
> index b3a4aae..82775b4 100644
> --- a/src/xenvif/pdo.c
> +++ b/src/xenvif/pdo.c
> @@ -1180,6 +1180,45 @@ fail1:
>       return status;
>   }
>   
> +static NTSTATUS
> +PdoGetInterfaceLuid(
> +    IN  PXENVIF_PDO Pdo,
> +    IN  HANDLE      Key,
> +    OUT PNET_LUID   Luid
> +    )
> +{
> +    ULONG           Value;
> +    NTSTATUS        status;
> +
> +    UNREFERENCED_PARAMETER(Pdo);
> +
> +    status = RegistryQueryDwordValue(Key,
> +                                     "*IfType",
> +                                     &Value);
> +    if (!NT_SUCCESS(status))
> +        goto fail1;
> +
> +    Luid->Info.IfType = Value;
> +
> +    status = RegistryQueryDwordValue(Key,
> +                                     "NetLuidIndex",
> +                                     &Value);
> +    if (!NT_SUCCESS(status))
> +        goto fail2;
> +
> +    Luid->Info.NetLuidIndex = Value;
> +
> +    return STATUS_SUCCESS;
> +
> +fail2:
> +    Error("fail2\n");
> +
> +fail1:
> +    Error("fail1 (%08x)\n", status);
> +
> +    return status;
> +}
> +
>   static VOID
>   PdoUnplugRequest(
>       IN  PXENVIF_PDO Pdo,
> @@ -1216,7 +1255,6 @@ PdoStartDevice(
>       PIO_STACK_LOCATION  StackLocation;
>       HANDLE              SoftwareKey;
>       HANDLE              HardwareKey;
> -    ULONG               HasSettings;
>       GUID                Guid;
>       NTSTATUS            status;
>   
> @@ -1307,39 +1345,44 @@ PdoStartDevice(
>           goto fail9;
>       }
>   
> -    status = RegistryQueryDwordValue(SoftwareKey,
> -                                     "HasSettings",
> -                                     &HasSettings);
> -    if (!NT_SUCCESS(status))
> -        HasSettings = 0;
> -
> -    if (HasSettings == 0) {
> -        //
> -        // If there is a stack bound then restore any settings that
> -        // may have been saved from an aliasing emulated device.
> -        //
> -        status = PdoGetInterfaceGuid(Pdo, SoftwareKey, &Guid);
> +    //
> +    // If there is a stack bound then restore any settings that
> +    // may have been saved from an aliasing emulated device.
Not *just* an emulated device now IIUC, right?

  Paul