-------- Forwarded Message -------- Subject: [PATCH v4 00/32] KVM: s390: enable zPCI for interpretive execution Date: Mon, 14 Mar 2022 15:44:19 -0400 From: Matthew Rosato mjrosato@linux.ibm.com To: linux-s390@vger.kernel.org CC: kvm@vger.kernel.org, david@redhat.com, thuth@redhat.com, linux-kernel@vger.kernel.org, vneethv@linux.ibm.com, agordeev@linux.ibm.com, imbrenda@linux.ibm.com, will@kernel.org, frankja@linux.ibm.com, corbet@lwn.net, linux-doc@vger.kernel.org, pasic@linux.ibm.com, jgg@nvidia.com, gerald.schaefer@linux.ibm.com, borntraeger@linux.ibm.com, farman@linux.ibm.com, gor@linux.ibm.com, schnelle@linux.ibm.com, hca@linux.ibm.com, alex.williamson@redhat.com, freude@linux.ibm.com, pmorel@linux.ibm.com, cohuck@redhat.com, oberpar@linux.ibm.com, iommu@lists.linux-foundation.org, svens@linux.ibm.com, pbonzini@redhat.com

Note: A few patches in this series are dependent on Baolu's IOMMU domain ops split, which is currently in the next branch of linux-iommu. This series applies on top: https://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu.git Enable interpretive execution of zPCI instructions + adapter interruption forwarding for s390x KVM vfio-pci. This is done by introducing a new IOMMU domain for s390x (KVM-managed), indicating via vfio that this IOMMU domain should be used instead of the default, with subsequent management of the hardware assists being handled via a new KVM ioctl for zPCI management.

By allowing intepretation of zPCI instructions and firmware delivery of interrupts to guests, we can significantly reduce the frequency of guest SIE exits for zPCI. We then see additional gains by handling a hot-path instruction that can still intercept to the hypervisor (RPCIT) directly in kvm via the new IOMMU domain, whose map operations update the host DMA table with pinned guest entries over the specified range.

From the perspective of guest configuration, you passthrough zPCI devices in the same manner as before, with intepretation support being used by default if available in kernel+qemu.

Will reply with a link to the associated QEMU series.

Changelog v3->v4: v3: https://lore.kernel.org/kvm/20220204211536.321475-1-mjrosato@linux.ibm.com/ - Significant overhaul of the userspace API. Remove all vfio device feature ioctls. Remove CONFIG_VFIO_PCI_ZDEV, this is once again always built with vfio-pci for s390; IS_ENABLED checks can instead look at CONFIG_VFIO_PCI. Most earlier patches in the series could maintain their reviews, but some needed to be removed due to required code changes. - Instead use a KVM ioctl for zPCI management. The API is very similar to the feature ioctls used in the prior series, with an additional step to create an association between an iommu domain + KVM + zPCI device. - Introduce a new iommu domain ops type for s390-iommu, to be used when KVM manages the IOMMU instead of in response to VFIO mapping ioctls - Add a iommu method for specifying the type of domain to allocate - Add a new type to vfio_iommu_type1 (KVM-owned) to trigger the allocation of the KVM-owned IOMMU domain when zPCI interpretation is requested. In this case, the KVM-owned type is specified on VFIO_SET_IOMMU. - Wire the RPCIT intercepts into the new IOMMU domain via the kernel IOMMU API - Remove a bunch of unnecessary symbol externs, make the associated functions static - Now that we keep a list of zPCI associated with a given KVM, we can do fh lookup on this list vs the list of all zPCI on the host. We only need to do a host-wide fh lookup during the initial device<->KVM association.

Matthew Rosato (32): s390/sclp: detect the zPCI load/store interpretation facility s390/sclp: detect the AISII facility s390/sclp: detect the AENI facility s390/sclp: detect the AISI facility s390/airq: pass more TPI info to airq handlers s390/airq: allow for airq structure that uses an input vector s390/pci: externalize the SIC operation controls and routine s390/pci: stash associated GISA designation s390/pci: export some routines related to RPCIT processing s390/pci: stash dtsm and maxstbl s390/pci: add helper function to find device by handle s390/pci: get SHM information from list pci s390/pci: return status from zpci_refresh_trans iommu: introduce iommu_domain_alloc_type and the KVM type vfio: introduce KVM-owned IOMMU type vfio-pci/zdev: add function handle to clp base capability KVM: s390: pci: add basic kvm_zdev structure iommu/s390: add support for IOMMU_DOMAIN_KVM KVM: s390: pci: do initial setup for AEN interpretation KVM: s390: pci: enable host forwarding of Adapter Event Notifications KVM: s390: mechanism to enable guest zPCI Interpretation KVM: s390: pci: routines for (dis)associating zPCI devices with a KVM KVM: s390: pci: provide routines for enabling/disabling interpretation KVM: s390: pci: provide routines for enabling/disabling interrupt forwarding KVM: s390: pci: provide routines for enabling/disabling IOAT assist KVM: s390: pci: handle refresh of PCI translations KVM: s390: intercept the rpcit instruction KVM: s390: add KVM_S390_ZPCI_OP to manage guest zPCI devices vfio-pci/zdev: add DTSM to clp group capability KVM: s390: introduce CPU feature for zPCI Interpretation MAINTAINERS: additional files related kvm s390 pci passthrough MAINTAINERS: update s390 IOMMU entry

Documentation/virt/kvm/api.rst | 60 +++ MAINTAINERS | 4 +- arch/s390/include/asm/airq.h | 7 +- arch/s390/include/asm/kvm_host.h | 7 + arch/s390/include/asm/kvm_pci.h | 40 ++ arch/s390/include/asm/pci.h | 12 + arch/s390/include/asm/pci_clp.h | 11 +- arch/s390/include/asm/pci_dma.h | 3 + arch/s390/include/asm/pci_insn.h | 31 +- arch/s390/include/asm/sclp.h | 4 + arch/s390/include/asm/tpi.h | 13 + arch/s390/include/uapi/asm/kvm.h | 1 + arch/s390/kvm/Makefile | 1 + arch/s390/kvm/interrupt.c | 95 +++- arch/s390/kvm/kvm-s390.c | 90 +++- arch/s390/kvm/kvm-s390.h | 10 + arch/s390/kvm/pci.c | 833 +++++++++++++++++++++++++++++++ arch/s390/kvm/pci.h | 63 +++ arch/s390/kvm/priv.c | 46 ++ arch/s390/pci/pci.c | 31 ++ arch/s390/pci/pci_clp.c | 28 +- arch/s390/pci/pci_dma.c | 7 +- arch/s390/pci/pci_insn.c | 15 +- arch/s390/pci/pci_irq.c | 48 +- drivers/iommu/Kconfig | 8 + drivers/iommu/Makefile | 1 + drivers/iommu/iommu.c | 7 + drivers/iommu/s390-iommu.c | 53 +- drivers/iommu/s390-iommu.h | 53 ++ drivers/iommu/s390-kvm-iommu.c | 469 +++++++++++++++++ drivers/s390/char/sclp_early.c | 4 + drivers/s390/cio/airq.c | 12 +- drivers/s390/cio/qdio_thinint.c | 6 +- drivers/s390/crypto/ap_bus.c | 9 +- drivers/s390/virtio/virtio_ccw.c | 6 +- drivers/vfio/pci/vfio_pci_zdev.c | 17 +- drivers/vfio/vfio_iommu_type1.c | 12 +- include/linux/iommu.h | 12 + include/uapi/linux/kvm.h | 43 ++ include/uapi/linux/vfio.h | 6 + include/uapi/linux/vfio_zdev.h | 6 + 41 files changed, 2090 insertions(+), 94 deletions(-) create mode 100644 arch/s390/include/asm/kvm_pci.h create mode 100644 arch/s390/kvm/pci.c create mode 100644 arch/s390/kvm/pci.h create mode 100644 drivers/iommu/s390-iommu.h create mode 100644 drivers/iommu/s390-kvm-iommu.c