On Mon, 14 Mar 2022 15:44:34 -0400 Matthew Rosato <mjrosato@xxxxxxxxxxxxx> wrote: > s390x will introduce a new IOMMU domain type where the mappings are > managed by KVM rather than in response to userspace mapping ioctls. Allow > for specifying this type on the VFIO_SET_IOMMU ioctl and triggering the > appropriate iommu interface for overriding the default domain. > > Signed-off-by: Matthew Rosato <mjrosato@xxxxxxxxxxxxx> > --- > drivers/vfio/vfio_iommu_type1.c | 12 +++++++++++- > include/uapi/linux/vfio.h | 6 ++++++ > 2 files changed, 17 insertions(+), 1 deletion(-) > > diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c > index 9394aa9444c1..0bec97077d61 100644 > --- a/drivers/vfio/vfio_iommu_type1.c > +++ b/drivers/vfio/vfio_iommu_type1.c > @@ -77,6 +77,7 @@ struct vfio_iommu { > bool nesting; > bool dirty_page_tracking; > bool container_open; > + bool kvm; > struct list_head emulated_iommu_groups; > }; > > @@ -2203,7 +2204,12 @@ static int vfio_iommu_type1_attach_group(void *iommu_data, > goto out_free_group; > > ret = -EIO; > - domain->domain = iommu_domain_alloc(bus); > + > + if (iommu->kvm) > + domain->domain = iommu_domain_alloc_type(bus, IOMMU_DOMAIN_KVM); > + else > + domain->domain = iommu_domain_alloc(bus); > + > if (!domain->domain) > goto out_free_domain; > > @@ -2552,6 +2558,9 @@ static void *vfio_iommu_type1_open(unsigned long arg) > case VFIO_TYPE1v2_IOMMU: > iommu->v2 = true; > break; > + case VFIO_KVM_IOMMU: > + iommu->kvm = true; > + break; > default: > kfree(iommu); > return ERR_PTR(-EINVAL); > @@ -2637,6 +2646,7 @@ static int vfio_iommu_type1_check_extension(struct vfio_iommu *iommu, > case VFIO_TYPE1_NESTING_IOMMU: > case VFIO_UNMAP_ALL: > case VFIO_UPDATE_VADDR: > + case VFIO_KVM_IOMMU: > return 1; > case VFIO_DMA_CC_IOMMU: > if (!iommu) > diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h > index ef33ea002b0b..666edb6957ac 100644 > --- a/include/uapi/linux/vfio.h > +++ b/include/uapi/linux/vfio.h > @@ -52,6 +52,12 @@ > /* Supports the vaddr flag for DMA map and unmap */ > #define VFIO_UPDATE_VADDR 10 > > +/* > + * The KVM_IOMMU type implies that the hypervisor will control the mappings > + * rather than userspace > + */ > +#define VFIO_KVM_IOMMU 11 Then why is this hosted in the type1 code that exposes a wide variety of userspace interfaces? Thanks, Alex