[PATCH v3 0/7] Make the rest of the VFIO driver interface use vfio_device

Jason Gunthorpe
2022-05-02T17:31:43Z

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.

v3:
- 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 | 288 ++----------------
include/linux/vfio.h | 21 +-
10 files changed, 102 insertions(+), 351 deletions(-)

base-commit: 676d7cda1a3c19872428a9bc818577a1aafafdd5
--
2.36.0