On 13/12/2015 09:08, Shmulik Ladkani wrote:
> Following the previous patch which changed pvscsi to be a pci express
> device, this patch introduces a boolean property 'x-disable-pcie'.
>
> Its default value is false, exposing pvscsi as a pcie device.
>
> Setting 'x-disable-pcie' to 'on' preserves the old 'pci device' (non
> express) behavior. This allows migration to older versions.
>
> Signed-off-by: Shmulik Ladkani <shmulik.ladk...@ravellosystems.com>
> ---
> hw/scsi/vmw_pvscsi.c | 2 ++
> include/hw/compat.h | 4 ++++
> 2 files changed, 6 insertions(+)
>
> diff --git a/hw/scsi/vmw_pvscsi.c b/hw/scsi/vmw_pvscsi.c
> index fb53b24..6b4b989 100644
> --- a/hw/scsi/vmw_pvscsi.c
> +++ b/hw/scsi/vmw_pvscsi.c
> @@ -1241,6 +1241,8 @@ static Property pvscsi_properties[] = {
> DEFINE_PROP_UINT8("use_msg", PVSCSIState, use_msg, 1),
> DEFINE_PROP_BIT("x-old-pci-configuration", PVSCSIState, compat_flags,
> PVSCSI_COMPAT_OLD_PCI_CONFIGURATION_BIT, false),
> + DEFINE_PROP_BIT("x-disable-pcie", PVSCSIState, compat_flags,
> + PVSCSI_COMPAT_DISABLE_PCIE_BIT, false),
> DEFINE_PROP_END_OF_LIST(),
> };
>
> diff --git a/include/hw/compat.h b/include/hw/compat.h
> index 66e4aff..bcb36ef 100644
> --- a/include/hw/compat.h
> +++ b/include/hw/compat.h
> @@ -11,6 +11,10 @@
> .property = "x-old-pci-configuration",\
> .value = "on",\
> },{\
> + .driver = "pvscsi",\
> + .property = "x-disable-pcie",\
> + .value = "on",\
> + },{\
> .driver = "e1000",\
> .property = "extra_mac_registers",\
> .value = "off",\
>
This series is okay, but the use of "x-" in the compat properties struck
me as odd.
I see that the "x-" prefix was first introduced for compat properties in
commit 1811e64 ("hw/virtio: Add PCIe capability to virtio devices",
2015-11-10). The rationale for "x-" was either 1) to provide fine
tuning for debugging-like options; 2) for places where the API is known
to be somewhat broken and will be fixed later.
Marcel, Michael, what was the justification for using "x-" in commit
1811e64? That said, I wouldn't mind using the opportunity of "x-" to
remove the double negation and rename the property to just "pcie". :)
Paolo
