Re: [Qemu-devel] [PATCH 2/2] gen_pcie_root_port: Add ACS (Access Control Services) capability

[Alex Williamson]

On Wed, 23 Jan 2019 19:28:00 +0100
Knut Omang <address@hidden> wrote:

> Claiming ACS support allows passthrough of an emulated device
> (in a nested virt.setting) with VFIO without Alex Williamson's patch
> for the pcie_acs_override kernel parameter.
> A similar need appears on Windows with Hyper-V
> 
> Signed-off-by: Knut Omang <address@hidden>
> ---
>  hw/pci-bridge/gen_pcie_root_port.c | 2 ++
>  hw/pci-bridge/ioh3420.c            | 1 -
>  hw/pci-bridge/pcie_root_port.c     | 3 +++
>  include/hw/pci/pcie_port.h         | 1 +
>  4 files changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/hw/pci-bridge/gen_pcie_root_port.c 
> b/hw/pci-bridge/gen_pcie_root_port.c
> index 9766edb..b5a5ecc 100644
> --- a/hw/pci-bridge/gen_pcie_root_port.c
> +++ b/hw/pci-bridge/gen_pcie_root_port.c
> @@ -20,6 +20,7 @@
>          OBJECT_CHECK(GenPCIERootPort, (obj), TYPE_GEN_PCIE_ROOT_PORT)
>  
>  #define GEN_PCIE_ROOT_PORT_AER_OFFSET           0x100
> +#define GEN_PCIE_ROOT_PORT_ACS_OFFSET           0x148

Perhaps (GEN_PCIE_ROOT_PORT_AER_OFFSET + PCI_ERR_SIZEOF)

>  #define GEN_PCIE_ROOT_PORT_MSIX_NR_VECTOR       1
>  
>  typedef struct GenPCIERootPort {
> @@ -149,6 +150,7 @@ static void gen_rp_dev_class_init(ObjectClass *klass, 
> void *data)
>      rpc->interrupts_init = gen_rp_interrupts_init;
>      rpc->interrupts_uninit = gen_rp_interrupts_uninit;
>      rpc->aer_offset = GEN_PCIE_ROOT_PORT_AER_OFFSET;
> +    rpc->acs_offset = GEN_PCIE_ROOT_PORT_ACS_OFFSET;
>  }
>  
>  static const TypeInfo gen_rp_dev_info = {
> diff --git a/hw/pci-bridge/ioh3420.c b/hw/pci-bridge/ioh3420.c
> index 81f2de6..2064939 100644
> --- a/hw/pci-bridge/ioh3420.c
> +++ b/hw/pci-bridge/ioh3420.c
> @@ -71,7 +71,6 @@ static int ioh3420_interrupts_init(PCIDevice *d, Error 
> **errp)
>      if (rc < 0) {
>          assert(rc == -ENOTSUP);
>      }
> -

Unrelated

>      return rc;
>  }
>  
> diff --git a/hw/pci-bridge/pcie_root_port.c b/hw/pci-bridge/pcie_root_port.c
> index 34ad767..c33a493 100644
> --- a/hw/pci-bridge/pcie_root_port.c
> +++ b/hw/pci-bridge/pcie_root_port.c
> @@ -106,6 +106,9 @@ static void rp_realize(PCIDevice *d, Error **errp)
>      pcie_aer_root_init(d);
>      rp_aer_vector_update(d);
>  
> +    if (rpc->acs_offset) {
> +        pcie_acs_init(d, rpc->acs_offset, 0);
> +    }
>      return;
>  
>  err:
> diff --git a/include/hw/pci/pcie_port.h b/include/hw/pci/pcie_port.h
> index df242a0..09586f4 100644
> --- a/include/hw/pci/pcie_port.h
> +++ b/include/hw/pci/pcie_port.h
> @@ -78,6 +78,7 @@ typedef struct PCIERootPortClass {
>      int exp_offset;
>      int aer_offset;
>      int ssvid_offset;
> +    int acs_offset;    /* If nonzero, optional ACS capability offset */
>      int ssid;
>  } PCIERootPortClass;
>