[PATCH v4 0/7] Make the rest of the VFIO driver interface use vfio_device

[Jason Gunthorpe <jgg@nvidia.com>]

Prior series have transformed other parts of VFIO from working on struct
device or struct vfio_group into working directly on struct
vfio_device. Based on that work we now have vfio_device's readily
available in all the drivers.

Update the rest of the driver facing API to use vfio_device as an input.

The following are switched from struct device to struct vfio_device:
  vfio_register_notifier()
  vfio_unregister_notifier()
  vfio_pin_pages()
  vfio_unpin_pages()
  vfio_dma_rw()

The following group APIs are obsoleted and removed by just using struct
vfio_device with the above:
  vfio_group_pin_pages()
  vfio_group_unpin_pages()
  vfio_group_iommu_domain()
  vfio_group_get_external_user_from_dev()

To retain the performance of the new device APIs relative to their group
versions optimize how vfio_group_add_container_user() is used to avoid
calling it when the driver must already guarantee the device is open and
the container_users incrd.

The remaining exported VFIO group interfaces are only used by kvm, and are
addressed by a parallel series.

This series is based on Christoph's gvt rework here:

 https://lore.kernel.org/all/5a8b9f48-2c32-8177-1c18-e3bd7bfde558@intel.com/

and so will need the PR merged first.

I have a followup series that needs this.

This is also part of the iommufd work - moving the driver facing interface
to vfio_device provides a much cleaner path to integrate with iommufd.

v4:
 - Use 'device' as the argument name for a struct vfio_device in vfio.c
v3: https://lore.kernel.org/r/0-v3-e131a9b6b467+14b6-vfio_mdev_no_group_jgg@nvidia.com
 - Based on VFIO's gvt/iommu merge
 - Remove mention of mdev_legacy_get_vfio_device() from commit message
 - Clarify commit message for vfio_dma_rw() conversion
 - Talk about the open_count change in the commit message
 - No code change
v2: https://lore.kernel.org/r/0-v2-6011bde8e0a1+5f-vfio_mdev_no_group_jgg@nvidia.com
 - Based on Christoph's series so mdev_legacy_get_vfio_device() is removed
 - Reflow indenting
 - Use vfio_assert_device_open() and WARN_ON_ONCE instead of open coding
   the assertion
v1: https://lore.kernel.org/r/0-v1-a8faf768d202+125dd-vfio_mdev_no_group_jgg@nvidia.com

Jason Gunthorpe (7):
  vfio: Make vfio_(un)register_notifier accept a vfio_device
  vfio/ccw: Remove mdev from struct channel_program
  vfio/mdev: Pass in a struct vfio_device * to vfio_pin/unpin_pages()
  vfio/mdev: Pass in a struct vfio_device * to vfio_dma_rw()
  drm/i915/gvt: Change from vfio_group_(un)pin_pages to
    vfio_(un)pin_pages
  vfio: Remove dead code
  vfio: Remove calls to vfio_group_add_container_user()

 .../driver-api/vfio-mediated-device.rst       |   4 +-
 drivers/gpu/drm/i915/gvt/gvt.h                |   5 +-
 drivers/gpu/drm/i915/gvt/kvmgt.c              |  51 ++-
 drivers/s390/cio/vfio_ccw_cp.c                |  47 +--
 drivers/s390/cio/vfio_ccw_cp.h                |   4 +-
 drivers/s390/cio/vfio_ccw_fsm.c               |   3 +-
 drivers/s390/cio/vfio_ccw_ops.c               |   7 +-
 drivers/s390/crypto/vfio_ap_ops.c             |  23 +-
 drivers/vfio/vfio.c                           | 299 +++---------------
 include/linux/vfio.h                          |  21 +-
 10 files changed, 109 insertions(+), 355 deletions(-)


base-commit: 676d7cda1a3c19872428a9bc818577a1aafafdd5
-- 
2.36.0