Hi Shameer, On 11/20/25 2:22 PM, Shameer Kolothum wrote: > Modify get_cap() callback so that it can return cap via an output > uint64_t param. And add support for generic iommu hw capability > info and max_pasid_log2(pasid width). > > Reviewed-by: Jonathan Cameron <[email protected]> > Signed-off-by: Shameer Kolothum <[email protected]> > --- > backends/iommufd.c | 23 ++++++++++++++++++----- > hw/i386/intel_iommu.c | 8 +++++--- > hw/vfio/container-legacy.c | 8 ++++++-- > include/system/host_iommu_device.h | 18 ++++++++++++------ > 4 files changed, 41 insertions(+), 16 deletions(-) > > diff --git a/backends/iommufd.c b/backends/iommufd.c > index 6381f9664b..718d63f5cf 100644 > --- a/backends/iommufd.c > +++ b/backends/iommufd.c > @@ -523,19 +523,32 @@ bool > host_iommu_device_iommufd_detach_hwpt(HostIOMMUDeviceIOMMUFD *idev, > return idevc->detach_hwpt(idev, errp); > } > > -static int hiod_iommufd_get_cap(HostIOMMUDevice *hiod, int cap, Error **errp) > +static int hiod_iommufd_get_cap(HostIOMMUDevice *hiod, int cap_id, > + uint64_t *out_cap, Error **errp) > { > HostIOMMUDeviceCaps *caps = &hiod->caps; > > - switch (cap) { > + g_assert(out_cap); > + > + switch (cap_id) { > case HOST_IOMMU_DEVICE_CAP_IOMMU_TYPE: > - return caps->type; > + *out_cap = caps->type; > + break; > case HOST_IOMMU_DEVICE_CAP_AW_BITS: > - return vfio_device_get_aw_bits(hiod->agent); > + *out_cap = vfio_device_get_aw_bits(hiod->agent); > + break; > + case HOST_IOMMU_DEVICE_CAP_GENERIC_HW: > + *out_cap = caps->hw_caps; > + break; > + case HOST_IOMMU_DEVICE_CAP_MAX_PASID_LOG2: > + *out_cap = caps->max_pasid_log2; > + break; > default: > - error_setg(errp, "%s: unsupported capability %x", hiod->name, cap); > + *out_cap = 0; not sure it is needed.
besides Reviewed-by: Eric Auger <[email protected]> Eric > + error_setg(errp, "%s: unsupported capability %x", hiod->name, > cap_id); > return -EINVAL; > } > + return 0; > } > > static void hiod_iommufd_class_init(ObjectClass *oc, const void *data) > diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c > index 78b142ccea..d5c131a814 100644 > --- a/hw/i386/intel_iommu.c > +++ b/hw/i386/intel_iommu.c > @@ -4605,6 +4605,7 @@ static bool vtd_check_hiod(IntelIOMMUState *s, > HostIOMMUDevice *hiod, > Error **errp) > { > HostIOMMUDeviceClass *hiodc = HOST_IOMMU_DEVICE_GET_CLASS(hiod); > + uint64_t out_cap; > int ret; > > if (!hiodc->get_cap) { > @@ -4613,12 +4614,13 @@ static bool vtd_check_hiod(IntelIOMMUState *s, > HostIOMMUDevice *hiod, > } > > /* Common checks */ > - ret = hiodc->get_cap(hiod, HOST_IOMMU_DEVICE_CAP_AW_BITS, errp); > + ret = hiodc->get_cap(hiod, HOST_IOMMU_DEVICE_CAP_AW_BITS, &out_cap, > errp); > if (ret < 0) { > return false; > } > - if (s->aw_bits > ret) { > - error_setg(errp, "aw-bits %d > host aw-bits %d", s->aw_bits, ret); > + if (s->aw_bits > out_cap) { > + error_setg(errp, "aw-bits %d > host aw-bits 0x%" PRIx64, s->aw_bits, > + out_cap); > return false; > } > > diff --git a/hw/vfio/container-legacy.c b/hw/vfio/container-legacy.c > index 32c260b345..1acf063762 100644 > --- a/hw/vfio/container-legacy.c > +++ b/hw/vfio/container-legacy.c > @@ -1203,15 +1203,19 @@ static bool hiod_legacy_vfio_realize(HostIOMMUDevice > *hiod, void *opaque, > } > > static int hiod_legacy_vfio_get_cap(HostIOMMUDevice *hiod, int cap, > - Error **errp) > + uint64_t *out_cap, Error **errp) > { > + g_assert(out_cap); > + > switch (cap) { > case HOST_IOMMU_DEVICE_CAP_AW_BITS: > - return vfio_device_get_aw_bits(hiod->agent); > + *out_cap = vfio_device_get_aw_bits(hiod->agent); > + break; > default: > error_setg(errp, "%s: unsupported capability %x", hiod->name, cap); > return -EINVAL; > } > + return 0; > } > > static GList * > diff --git a/include/system/host_iommu_device.h > b/include/system/host_iommu_device.h > index bfb2b60478..4e891e5225 100644 > --- a/include/system/host_iommu_device.h > +++ b/include/system/host_iommu_device.h > @@ -88,19 +88,21 @@ struct HostIOMMUDeviceClass { > * @get_cap: check if a host IOMMU device capability is supported. > * > * Optional callback, if not implemented, hint not supporting query > - * of @cap. > + * of @cap_id. > * > * @hiod: pointer to a host IOMMU device instance. > * > - * @cap: capability to check. > + * @cap_id: capability to check. > + * > + * @out_cap: 0 if a @cap_id is unsupported or else the capability > + * value for @cap_id. > * > * @errp: pass an Error out when fails to query capability. > * > - * Returns: <0 on failure, 0 if a @cap is unsupported, or else > - * 1 or some positive value for some special @cap, > - * i.e., HOST_IOMMU_DEVICE_CAP_AW_BITS. > + * Returns: <0 if @cap_id is not supported, 0 on success. > */ > - int (*get_cap)(HostIOMMUDevice *hiod, int cap, Error **errp); > + int (*get_cap)(HostIOMMUDevice *hiod, int cap_id, uint64_t *out_cap, > + Error **errp); > /** > * @get_iova_ranges: Return the list of usable iova_ranges along with > * @hiod Host IOMMU device > @@ -123,6 +125,10 @@ struct HostIOMMUDeviceClass { > */ > #define HOST_IOMMU_DEVICE_CAP_IOMMU_TYPE 0 > #define HOST_IOMMU_DEVICE_CAP_AW_BITS 1 > +/* Generic IOMMU HW capability info */ > +#define HOST_IOMMU_DEVICE_CAP_GENERIC_HW 2 > +/* PASID width */ > +#define HOST_IOMMU_DEVICE_CAP_MAX_PASID_LOG2 3 > > #define HOST_IOMMU_DEVICE_CAP_AW_BITS_MAX 64 > #endif
