[PATCH v9 00/21] KVM: s390: enable zPCI for interpretive execution

[Matthew Rosato]

Enable interpretive execution of zPCI instructions + adapter interruption
forwarding for s390x KVM vfio-pci.  This is done by triggering a routine
when the VFIO group is associated with the KVM guest, transmitting to
firmware a special token (GISA designation) to enable that specific guest
for interpretive execution on that zPCI device.  Load/store interpreation
enablement is then controlled by userspace (based upon whether or not a
SHM bit is placed in the virtual function handle).  Adapter Event
Notification interpretation is controlled from userspace via a new KVM
ioctl.

By allowing intepretation of zPCI instructions and firmware delivery of
interrupts to guests, we can reduce the frequency of guest SIE exits for
zPCI.  

>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 follow up with a link the most recent QEMU series.

Changelog v8->v9:
- Rebase on top of 5.19-rc1, adjust ioctl and capability defines
- s/kzdev = 0/kzdev = NULL/ (Alex)
- rename vfio_pci_zdev_open to vfio_pci_zdev_open_device (Jason)
- rename vfio_pci_zdev_release to vfio_pci_zdev_close_device (Jason)
- make vfio_pci_zdev_close_device return void, instead WARN_ON or ignore
  errors in lower level function (kvm_s390_pci_unregister_kvm) (Jason)
- remove notifier accidentally left in struct zpci_dev + associated
  include statment (Jason)
- Remove patch 'KVM: s390: introduce CPU feature for zPCI Interpretation'
  based on discussion in QEMU thread.

Matthew Rosato (21):
  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: stash dtsm and maxstbl
  vfio/pci: introduce CONFIG_VFIO_PCI_ZDEV_KVM
  KVM: s390: pci: add basic kvm_zdev structure
  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: provide routines for enabling/disabling interrupt
    forwarding
  KVM: s390: pci: add routines to start/stop interpretive execution
  vfio-pci/zdev: add open/close device hooks
  vfio-pci/zdev: add function handle to clp base capability
  vfio-pci/zdev: different maxstbl for interpreted devices
  KVM: s390: add KVM_S390_ZPCI_OP to manage guest zPCI devices
  MAINTAINERS: additional files related kvm s390 pci passthrough

 Documentation/virt/kvm/api.rst   |  47 +++
 MAINTAINERS                      |   1 +
 arch/s390/include/asm/airq.h     |   7 +-
 arch/s390/include/asm/kvm_host.h |  23 ++
 arch/s390/include/asm/pci.h      |  11 +
 arch/s390/include/asm/pci_clp.h  |   9 +-
 arch/s390/include/asm/pci_insn.h |  29 +-
 arch/s390/include/asm/sclp.h     |   4 +
 arch/s390/include/asm/tpi.h      |  13 +
 arch/s390/kvm/Makefile           |   1 +
 arch/s390/kvm/interrupt.c        |  96 ++++-
 arch/s390/kvm/kvm-s390.c         |  83 +++-
 arch/s390/kvm/kvm-s390.h         |  10 +
 arch/s390/kvm/pci.c              | 690 +++++++++++++++++++++++++++++++
 arch/s390/kvm/pci.h              |  88 ++++
 arch/s390/pci/pci.c              |  16 +
 arch/s390/pci/pci_clp.c          |   7 +
 arch/s390/pci/pci_insn.c         |   4 +-
 arch/s390/pci/pci_irq.c          |  48 ++-
 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/Kconfig         |  11 +
 drivers/vfio/pci/Makefile        |   2 +-
 drivers/vfio/pci/vfio_pci_core.c |  10 +-
 drivers/vfio/pci/vfio_pci_zdev.c |  35 +-
 include/linux/sched/user.h       |   3 +-
 include/linux/vfio_pci_core.h    |  12 +-
 include/uapi/linux/kvm.h         |  31 ++
 include/uapi/linux/vfio_zdev.h   |   7 +
 32 files changed, 1279 insertions(+), 56 deletions(-)
 create mode 100644 arch/s390/kvm/pci.c
 create mode 100644 arch/s390/kvm/pci.h

-- 
2.27.0