Re: [PATCH] hw/ppc: Improve build for PPC VFIO

["Cédric Le Goater" <clg@redhat.com>]

On 11/23/23 07:01, Zhenzhong Duan wrote:
> VFIO is not a required subsystem for the pseries machine but it's
> force enabled currently. When --without-default-devices is used
> to drop some default devices including vfio-pci, vfio core code
> is still kept which is unnecessary.
> 
> Introduce a stub file to hold stub functions of VFIO EEH hooks,
> then vfio core could be compiled out.
> 
> Suggested-by: Cédric Le Goater <clg@redhat.com>
> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>


Nick,

I will take this patch through the vfio tree if that's OK for you.

> ---
> Based on vfio-next/vfio-8.2
> 
>   hw/ppc/spapr_pci_vfio_stub.c | 33 +++++++++++++++++++++++++++++++++
>   hw/ppc/Kconfig               |  2 +-
>   hw/ppc/meson.build           |  6 +++---
>   3 files changed, 37 insertions(+), 4 deletions(-)
>   create mode 100644 hw/ppc/spapr_pci_vfio_stub.c
> 
> diff --git a/hw/ppc/spapr_pci_vfio_stub.c b/hw/ppc/spapr_pci_vfio_stub.c
> new file mode 100644
> index 0000000000..adb3fb5e35
> --- /dev/null
> +++ b/hw/ppc/spapr_pci_vfio_stub.c
> @@ -0,0 +1,33 @@
> +#include "qemu/osdep.h"
> +#include "hw/pci-host/spapr.h"
> +
> +bool spapr_phb_eeh_available(SpaprPhbState *sphb)
> +{
> +    return false;
> +}
> +
> +void spapr_phb_vfio_reset(DeviceState *qdev)
> +{
> +}
> +
> +int spapr_phb_vfio_eeh_set_option(SpaprPhbState *sphb,
> +                                  unsigned int addr, int option)
> +{
> +    return RTAS_OUT_NOT_SUPPORTED;
> +}
> +
> +int spapr_phb_vfio_eeh_get_state(SpaprPhbState *sphb, int *state)
> +{
> +    return RTAS_OUT_NOT_SUPPORTED;
> +}
> +
> +int spapr_phb_vfio_eeh_reset(SpaprPhbState *sphb, int option)
> +{
> +    return RTAS_OUT_NOT_SUPPORTED;
> +}
> +
> +int spapr_phb_vfio_eeh_configure(SpaprPhbState *sphb)
> +{
> +    return RTAS_OUT_NOT_SUPPORTED;
> +}
> +
> diff --git a/hw/ppc/Kconfig b/hw/ppc/Kconfig
> index edc6d2d139..b8dabdbfbe 100644
> --- a/hw/ppc/Kconfig
> +++ b/hw/ppc/Kconfig
> @@ -3,11 +3,11 @@ config PSERIES
>       imply PCI_DEVICES
>       imply TEST_DEVICES
>       imply VIRTIO_VGA
> +    imply VFIO if LINUX   # needed by spapr_pci_vfio.c

Zhenzhong,

I changed VFIO to VFIO_PCI because PPC only supports this type
of passthrough devices.

With that,

Reviewed-by: Cédric Le Goater <clg@redhat.com>

Thanks,

C.



>       select NVDIMM
>       select DIMM
>       select PCI
>       select SPAPR_VSCSI
> -    select VFIO_PCI if LINUX   # needed by spapr_pci_vfio.c
>       select XICS
>       select XIVE
>       select MSI_NONBROKEN
> diff --git a/hw/ppc/meson.build b/hw/ppc/meson.build
> index ea44856d43..2df5db2eef 100644
> --- a/hw/ppc/meson.build
> +++ b/hw/ppc/meson.build
> @@ -34,9 +34,9 @@ ppc_ss.add(when: ['CONFIG_PSERIES', 'CONFIG_TCG'], if_true: files(
>     'spapr_softmmu.c',
>   ))
>   ppc_ss.add(when: 'CONFIG_SPAPR_RNG', if_true: files('spapr_rng.c'))
> -ppc_ss.add(when: ['CONFIG_PSERIES', 'CONFIG_LINUX'], if_true: files(
> -  'spapr_pci_vfio.c',
> -))
> +ppc_ss.add(when: [ 'CONFIG_VFIO_PCI', 'CONFIG_PSERIES', 'CONFIG_LINUX'],
> +           if_true: files('spapr_pci_vfio.c'),
> +           if_false: files('spapr_pci_vfio_stub.c'))
>   
>   # IBM PowerNV
>   ppc_ss.add(when: 'CONFIG_POWERNV', if_true: files(