[PATCH v12 00/17] s390x/pci: Implement migration for emulated devices

[Konstantin Shkolnyy <kshk@linux.ibm.com>]

ATTENTION! This series is built to apply on top of https://gitlab.com/efarman/qemu/-/tree/s390-next.

Up until now QEMU marked any zPCI device as "unmigratable."

This patch series adds support for migrating emulated devices, which are
simpler to migrate. It leaves VFIO devices still unmigratable.

To enable migration, the device state needs to be saved/restored to/from
the migration stream.

There are 2 kinds of emulated devices - those that use the zPCI IOMMU page
table emulation in QEMU (e.g., Intel IGB NIC), and those that don't (virtio).
This is important to note for testing purposes.

This change was tested on IGB, virtio-net and virtio-blk devices by running
I/O on them while performing "virsh managedsave, virsh start" and also live
migration to another host and back.

Changes in v12:
 - patch 14: Add a message to an error path that didn't have it.
 - patch 15: New. Extract here an isolated change from the next patch to make it smaller.
 - patch 16 (formerly 15):
   - Simplify error handling on s390_pci_ioat_validate() failure,
   - Put an assert() with a comment into unreacheable branch.

Konstantin Shkolnyy (16):
  s390x/pci: Create function to contain translation status check
  s390x/pci: Move iommu_mr from S390PCIIOMMU to S390PCIBusDevice
  s390x/pci: Move dm_mr from S390PCIIOMMU to S390PCIBusDevice
  s390x/pci: Move iotlb from S390PCIIOMMU to S390PCIBusDevice
  s390x/pci: Remove a ptr to S390PCIBusDevice from S390PCIIOMMU
  s390x/pci: Move/rename enabled from S390PCIIOMMU to S390PCIBusDevice
  s390x/pci: Move dma_limit from S390PCIIOMMU to S390PCIBusDevice
  s390x/pci: Move g_iota from S390PCIIOMMU to S390PCIBusDevice
  s390x/pci: Move pba from S390PCIIOMMU to S390PCIBusDevice
  s390x/pci: Move pal from S390PCIIOMMU to S390PCIBusDevice
  s390x/pci: Move max_dma_limit from S390PCIIOMMU to S390PCIBusDevice
  s390x/pci: Add a comment explaining S390PCIIOMMU purpose
  s390x/pci: Move ioat sanity checks into new function, add error
    message
  s390x/pci: Provide each zpci device with a unique stable bus "path"
  s390x/pci: Implement migration for emulated devices
  s390x/pci: Create function to contain fmb_timer start

Matthew Rosato (1):
  s390x/pci: implement IOMMU replay

 hw/s390x/s390-pci-bus.c          | 528 +++++++++++++++++++++++++++----
 hw/s390x/s390-pci-inst.c         | 174 +++++-----
 hw/s390x/s390-pci-vfio.c         |   4 +-
 hw/s390x/s390-virtio-ccw.c       |   4 +
 include/hw/s390x/s390-pci-bus.h  |  43 ++-
 include/hw/s390x/s390-pci-inst.h |   7 +-
 6 files changed, 611 insertions(+), 149 deletions(-)

-- 
2.34.1