linux/drivers/vfio
Jason Gunthorpe a882c16a2b vfio/pci: Change vfio_pci_try_bus_reset() to use the dev_set
vfio_pci_try_bus_reset() is triggering a reset of the entire_dev set if
any device within it has accumulated a needs_reset. This reset can only be
done once all of the drivers operating the PCI devices to be reset are in
a known safe state.

Make this clearer by directly operating on the dev_set instead of the
vfio_pci_device. Rename the function to vfio_pci_dev_set_try_reset().

Use the device list inside the dev_set to check that all drivers are in a
safe state instead of working backwards from the pci_device.

The dev_set->lock directly prevents devices from joining/leaving the set,
or changing their state, which further implies the pci_device cannot
change drivers or that the vfio_device be freed, eliminating the need for
get/put's.

If a pci_device to be reset is not in the dev_set then the reset cannot be
used as we can't know what the state of that driver is. Directly measure
this by checking that every pci_device is in the dev_set - which
effectively proves that VFIO drivers are attached to everything.

Remove the odd interaction around vfio_pci_set_power_state() - have the
only caller avoid its redundant vfio_pci_set_power_state() instead of
avoiding it inside vfio_pci_dev_set_try_reset().

This restructuring corrects a call to pci_dev_driver() without holding the
device_lock() and removes a hard wiring to &vfio_pci_driver.

Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Link: https://lore.kernel.org/r/9-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-11 09:50:11 -06:00
..
fsl-mc vfio/fsl: Move to the device set infrastructure 2021-08-11 09:50:11 -06:00
mdev vfio: Provide better generic support for open/release vfio_device_ops 2021-08-11 09:50:10 -06:00
pci vfio/pci: Change vfio_pci_try_bus_reset() to use the dev_set 2021-08-11 09:50:11 -06:00
platform vfio/platform: Use open_device() instead of open coding a refcnt scheme 2021-08-11 09:50:11 -06:00
Kconfig vfio: Use config not menuconfig for VFIO_NOIOMMU 2021-08-02 15:23:42 -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: convert get_user_pages() --> pin_user_pages() 2020-07-27 13:43:38 -06:00
vfio_iommu_type1.c VFIO update for v5.14-rc1 2021-07-03 11:49:33 -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: Provide better generic support for open/release vfio_device_ops 2021-08-11 09:50:10 -06:00
virqfd.c vfio/virqfd: Drain events from eventfd in virqfd_wakeup() 2020-11-15 09:49:10 -05:00