Re: [PATCH v2] xio3130_upstream: Add ACS (Access Control Services) capability

[Paul Schlacter]

On Tue, Aug 16, 2022 at 6:11 PM Michael S. Tsirkin <mst@redhat.com> wrote:
>
> On Tue, Aug 16, 2022 at 05:16:38PM +0800, Paul Schlacter wrote:
> > v1 -> v2:
> > - Allow ACS to be disabled.
> > - Suggested by Michael S. Tsirkin, use disable-acs to set property.
> >
> > v1:
> > - Add ACS (Access Control Services) capability.
>
> changelog generally after ---
>
> >
> > If it is a pcie device, check that all devices on the path from
>
>
> Hmm I don't see any checks on a path. what does this refer to?

pci_acs_path_enabled, this function in the Linux kernel,
it means that if the device is a PCIe device,
check the path from the device to the root complex. If ACS is all enabled,
the device will become an iommu_group.
acs determine whether it is a separate iommu_group.
>
> >
> > the device to the root complex have ACS enabled, and then the
> >
> > device will become an iommu_group.
> >
> > it will have the effect of isolation
> >
> >
> >
> > Signed-off-by: wangliang <wlfightup@gmail.com>
> >
> > Signed-off-by: wangliang <wangliang40@baidu.com>
> >
>
> why two signatures?
>
> >
> > ---
>
> >
> >  hw/pci-bridge/xio3130_upstream.c | 12 +++++++++++-
> >
> >  1 file changed, 11 insertions(+), 1 deletion(-)
> >
>
> Patch has corrupted whitespace.
>
> >
> > diff --git a/hw/pci-bridge/xio3130_upstream.c b/hw/pci-bridge/
> > xio3130_upstream.c
> >
> > index 2df952222b..5433d06fb3 100644
> >
> > --- a/hw/pci-bridge/xio3130_upstream.c
> >
> > +++ b/hw/pci-bridge/xio3130_upstream.c
> >
> > @@ -24,6 +24,7 @@
> >
> >  #include "hw/pci/msi.h"
> >
> >  #include "hw/pci/pcie.h"
> >
> >  #include "hw/pci/pcie_port.h"
> >
> > +#include "hw/qdev-properties.h"
> >
> >  #include "migration/vmstate.h"
> >
> >  #include "qemu/module.h"
> >
> >
> >
> > @@ -59,6 +60,7 @@ static void xio3130_upstream_reset(DeviceState *qdev)
> >
> >  static void xio3130_upstream_realize(PCIDevice *d, Error **errp)
> >
> >  {
> >
> >      PCIEPort *p = PCIE_PORT(d);
> >
> > +    PCIESlot *s = PCIE_SLOT(d);
> >
> >      int rc;
> >
> >
> >
> >      pci_bridge_initfn(d, TYPE_PCIE_BUS);
> >
> > @@ -94,7 +96,9 @@ static void xio3130_upstream_realize(PCIDevice *d, Error
> > **errp)
> >
> >          goto err;
> >
> >      }
> >
> >
> >
> > -    pcie_acs_init(d, XIO3130_ACS_OFFSET);
> >
> > +    if (!s->disable_acs) {
> >
> > +        pcie_acs_init(d, XIO3130_ACS_OFFSET);
> >
> > +    }
> >
> >      return;
> >
> >
> >
> >  err:
> >
> > @@ -113,6 +117,11 @@ static void xio3130_upstream_exitfn(PCIDevice *d)
> >
> >      pci_bridge_exitfn(d);
> >
> >  }
> >
> >
> >
> > +static Property xio3130_upstream_props[] = {
> >
> > +    DEFINE_PROP_BOOL("disable-acs", PCIESlot, disable_acs, false),
> >
> > +    DEFINE_PROP_END_OF_LIST()
> >
> > +};
> >
> > +
>
> I'd say prefix the property with "x-".

Do you want me to change it to this?
DEFINE_PROP_BOOL("x-disable-acs", PCIESlot, disable_acs, false),

disable_acs is a field in PCIESlot, which is also used by other code.
It may not be good to modify this field
>
>
> >
> >  static const VMStateDescription vmstate_xio3130_upstream = {
> >
> >      .name = "xio3130-express-upstream-port",
> >
> >      .priority = MIG_PRI_PCI_BUS,
> >
> > @@ -142,6 +151,7 @@ static void xio3130_upstream_class_init(ObjectClass 
> > *klass,
> > void *data)
> >
> >      dc->desc = "TI X3130 Upstream Port of PCI Express Switch";
> >
> >      dc->reset = xio3130_upstream_reset;
> >
> >      dc->vmsd = &vmstate_xio3130_upstream;
> >
> > +    device_class_set_props(dc, xio3130_upstream_props);
> >
> >  }
> >
>
> Seems to lack compat machinety for existing machine types.

DEFINE_PROP_BOOL("x-disable-acs", PCIESlot, disable_acs, true),
If I change the default value to true, can I not add compat machine
>
>
> >
> >
> >  static const TypeInfo xio3130_upstream_info = {
> >
> > --
> >
> > 2.24.3 (Apple Git-128)
> >
>