[PATCH v1 00/14] vfio: Device memory DMA mapping improvements

[Alex Williamson]

The primary goal of this series is to better manage device memory
mappings, both with a much simplified scheme to zap CPU mappings of
device memory using unmap_mapping_range() and also to restrict IOMMU
mappings of PFNMAPs to vfio device memory and drop those mappings on
device release.  This series updates vfio-pci to include the necessary
vma-to-pfn interface, allowing the type1 IOMMU backend to recognize
vfio device memory.  If other bus drivers support peer-to-peer DMA,
they should be updated with a similar callback and trigger the device
notifier on release.

RFC->v1:

 - Fix some incorrect ERR handling
 - Fix use of vm_pgoff to be compatible with unmap_mapping_range()
 - Add vma-to-pfn interfaces
 - Generic device-from-vma handling
 - pfnmap obj directly maps back to vfio_dma obj
 - No bypass for strict MMIO handling
 - Batch PFNMAP handling
 - Follow-on patches to cleanup "extern" usage and bare unsigned

Works in my environment, further testing always appreciated.  This
will need to be merged with a solution for concurrent fault handling.
Thanks especially to Jason Gunthorpe for previous reviews and
suggestions.  Thanks,

Alex

RFC:https://lore.kernel.org/kvm/161401167013.16443.8389863523766611711.stgit@xxxxxxxxxx/

---

Alex Williamson (14):
      vfio: Create vfio_fs_type with inode per device
      vfio: Update vfio_add_group_dev() API
      vfio: Export unmap_mapping_range() wrapper
      vfio/pci: Use vfio_device_unmap_mapping_range()
      vfio: Create a vfio_device from vma lookup
      vfio: Add vma to pfn callback
      vfio: Add a device notifier interface
      vfio/pci: Notify on device release
      vfio/type1: Refactor pfn_list clearing
      vfio/type1: Pass iommu and dma objects through to vaddr_get_pfn
      vfio/type1: Register device notifier
      vfio/type1: Support batching of device mappings
      vfio: Remove extern from declarations across vfio
      vfio: Cleanup use of bare unsigned


 Documentation/driver-api/vfio-mediated-device.rst |   19 +-
 Documentation/driver-api/vfio.rst                 |    8 -
 drivers/s390/cio/vfio_ccw_cp.h                    |   13 +
 drivers/s390/cio/vfio_ccw_private.h               |   14 +
 drivers/s390/crypto/vfio_ap_private.h             |    2 
 drivers/vfio/Kconfig                              |    1 
 drivers/vfio/fsl-mc/vfio_fsl_mc.c                 |    6 -
 drivers/vfio/fsl-mc/vfio_fsl_mc_private.h         |    7 -
 drivers/vfio/mdev/vfio_mdev.c                     |    5 
 drivers/vfio/pci/vfio_pci.c                       |  229 ++++-----------------
 drivers/vfio/pci/vfio_pci_intrs.c                 |   42 ++--
 drivers/vfio/pci/vfio_pci_private.h               |   69 +++---
 drivers/vfio/platform/vfio_platform_common.c      |    7 -
 drivers/vfio/platform/vfio_platform_irq.c         |   21 +-
 drivers/vfio/platform/vfio_platform_private.h     |   31 +--
 drivers/vfio/vfio.c                               |  154 ++++++++++++--
 drivers/vfio/vfio_iommu_type1.c                   |  234 +++++++++++++++------
 include/linux/vfio.h                              |  129 ++++++------
 18 files changed, 543 insertions(+), 448 deletions(-)