[00/17] vfio/pci: Remove duplicate code and logic from VFIO PCI interrupt management

Message

Reinette Chatre Feb. 2, 2024, 4:56 a.m. UTC

Hi Everybody,

Duplicate VFIO PCI interrupt management code and logic can be found
in two areas:
1) the VFIO PCI core (vfio_pci_core.c) directly accesses the
   VFIO PCI interrupt lock and data to duplicate actions available
   via the VFIO PCI interrupt management code (vfio_pci_intrs.c), and
2) the INTx and MSI/MSI-X interrupt management code within
   vfio_pci_intrs.c have duplicate logic.

This series addresses (1) and (2) by first containing VFIO PCI interrupt
management within the VFIO PCI interrupt management code found in
vfio_pci_intrs.c and then refactoring the VFIO PCI interrupt management
code (vfio_pci_intrs.c) to share common logic between INTx, MSI, and
MSI-X interrupt management.

Bulk of the changes result in the same actions as before this series.
Two functional changes to highlight:
a) "vfio/pci: Consistently acquire mutex for interrupt management"
   changes vfio_pci_core_disable()->vfio_pci_set_irqs_ioctl() to be
   called with the igate mutex held.
b) "vfio/pci: Preserve per-interrupt contexts" changes MSI/MSI-x
   interrupt management to preserve per-interrupt contexts across interrupt
   allocate/free.

This work was inspired by (and inherits a few patches from) the IMS [1]
enabling work but this work is submitted (and expected to be considered)
independent from IMS.

Any feedback will be appreciated.

Reinette

[1] https://lore.kernel.org/lkml/[e-mail]/

Reinette Chatre (17):
  vfio/pci: Use unsigned int instead of unsigned
  vfio/pci: Remove duplicate check from
    vfio_pci_set_ctx_trigger_single() wrappers
  vfio/pci: Consistently acquire mutex for interrupt management
  vfio/pci: Remove duplicate interrupt management from core VFIO PCI
  vfio/pci: Limit eventfd signaling to interrupt management code
  vfio/pci: Remove interrupt index interpretation from wrappers
  vfio/pci: Preserve per-interrupt contexts
  vfio/pci: Extract MSI/MSI-X specific code from common flow
  vfio/pci: Converge similar code flows
  vfio/pci: Extract INTx specific code from vfio_intx_set_signal()
  vfio/pci: Perform MSI/MSI-X interrupt management via callbacks
  vfio/pci: Remove msi term from generic code
  vfio/pci: Remove vfio_intx_set_signal()
  vfio/pci: Add utility to trigger INTx eventfd knowing interrupt
    context
  vfio/pci: Let enable and disable of interrupt types use same signature
  vfio/pci: Move vfio_msi_disable() to be with other MSI/MSI-X
    management code
  vfio/pci: Remove duplicate interrupt management flow

 drivers/vfio/pci/vfio_pci_core.c  |  49 ++-
 drivers/vfio/pci/vfio_pci_intrs.c | 510 ++++++++++++++++++------------
 2 files changed, 318 insertions(+), 241 deletions(-)

base-commit: 41bccc98fb7931d63d03f326a746ac4d429c1dd3