linux/drivers/vfio
Jason Gunthorpe eadd86f835 vfio: Remove calls to vfio_group_add_container_user()
When the open_device() op is called the container_users is incremented and
held incremented until close_device(). Thus, so long as drivers call
functions within their open_device()/close_device() region they do not
need to worry about the container_users.

These functions can all only be called between open_device() and
close_device():

  vfio_pin_pages()
  vfio_unpin_pages()
  vfio_dma_rw()
  vfio_register_notifier()
  vfio_unregister_notifier()

Eliminate the calls to vfio_group_add_container_user() and add
vfio_assert_device_open() to detect driver mis-use. This causes the
close_device() op to check device->open_count so always leave it elevated
while calling the op.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/7-v4-8045e76bf00b+13d-vfio_mdev_no_group_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2022-05-11 13:13:00 -06:00
..
fsl-mc bus: fsl-mc: fsl-mc-allocator: Rework MSI handling 2021-12-16 22:16:41 +01:00
mdev vfio/mdev: Use the driver core to create the 'remove' file 2022-04-21 07:36:56 -04:00
pci Improve mlx5 live migration driver 2022-05-11 13:08:49 -06:00
platform vfio: Move vfio_iommu_group_get() to vfio_register_group_dev() 2021-09-30 12:46:43 -06:00
Kconfig vfio: Use kconfig if XX/endif blocks instead of repeating 'depends on' 2021-08-26 10:36:51 -06:00
Makefile vfio/fsl-mc: Add VFIO framework skeleton for fsl-mc devices 2020-10-07 14:17:33 -06:00
vfio_iommu_spapr_tce.c vfio/spapr_tce: reject mediated devices 2021-09-30 12:46:44 -06:00
vfio_iommu_type1.c vfio/iommu_type1: replace kfree with kvfree 2021-12-21 12:30:34 -07:00
vfio_spapr_eeh.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
vfio.c vfio: Remove calls to vfio_group_add_container_user() 2022-05-11 13:13:00 -06:00
vfio.h vfio: clean up the check for mediated device in vfio_iommu_type1 2021-09-30 12:46:44 -06:00
virqfd.c vfio/virqfd: Drain events from eventfd in virqfd_wakeup() 2020-11-15 09:49:10 -05:00