On Wed, 21 Jul 2021 19:16:09 +0300
Yishai Hadas <yishaih@xxxxxxxxxx> wrote:
> From: Max Gurtovoy <mgurtovoy@xxxxxxxxxx>
>
> Now that vfio_pci has been split into two source modules, one focusing
> on the "struct pci_driver" (vfio_pci.c) and a toolbox library of code
> (vfio_pci_core.c), complete the split and move them into two different
> kernel modules.
>
> As before vfio_pci.ko continues to present the same interface under
> sysfs and this change will have no functional impact.
>
> Splitting into another module and adding exports allows creating new HW
> specific VFIO PCI drivers that can implement device specific
> functionality, such as VFIO migration interfaces or specialized device
> requirements.
>
> Signed-off-by: Max Gurtovoy <mgurtovoy@xxxxxxxxxx>
> Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
> Signed-off-by: Yishai Hadas <yishaih@xxxxxxxxxx>
> ---
> drivers/vfio/pci/Kconfig | 30 ++++++++------
> drivers/vfio/pci/Makefile | 8 ++--
> drivers/vfio/pci/vfio_pci.c | 14 ++-----
> drivers/vfio/pci/vfio_pci_config.c | 2 +-
> drivers/vfio/pci/vfio_pci_core.c | 41 ++++++++++++++++---
> drivers/vfio/pci/vfio_pci_igd.c | 2 +-
> drivers/vfio/pci/vfio_pci_intrs.c | 2 +-
> drivers/vfio/pci/vfio_pci_rdwr.c | 2 +-
> drivers/vfio/pci/vfio_pci_zdev.c | 2 +-
> .../pci => include/linux}/vfio_pci_core.h | 2 -
> 10 files changed, 66 insertions(+), 39 deletions(-)
> rename {drivers/vfio/pci => include/linux}/vfio_pci_core.h (99%)
>
> diff --git a/drivers/vfio/pci/Kconfig b/drivers/vfio/pci/Kconfig
> index afdab7d71e98..18898ae49919 100644
> --- a/drivers/vfio/pci/Kconfig
> +++ b/drivers/vfio/pci/Kconfig
> @@ -1,19 +1,31 @@
> # SPDX-License-Identifier: GPL-2.0-only
> -config VFIO_PCI
> +config VFIO_PCI_CORE
> tristate "VFIO support for PCI devices"
> depends on PCI
> depends on MMU
> select VFIO_VIRQFD
> select IRQ_BYPASS_MANAGER
> help
> - Support for the PCI VFIO bus driver. This is required to make
> - use of PCI drivers using the VFIO framework.
> + Support for using PCI devices with VFIO.
> +
> +if VFIO_PCI_CORE
> +config VFIO_PCI_MMAP
> + def_bool y if !S390
> +
> +config VFIO_PCI_INTX
> + def_bool y if !S390
> +
> +config VFIO_PCI
> + tristate "Generic VFIO support for any PCI device"
> + help
> + Support for the generic PCI VFIO bus driver which can connect any
> + PCI device to the VFIO framework.
>
> If you don't know what to do here, say N.
>
I'm still not happy with how this is likely to break users and even
downstreams when upgrading to a Kconfig with this change. A previously
selected VFIO_PCI comes out disabled unless the user is keen enough to
enable VFIO_PCI_CORE. I think I'd prefer to sacrifice the purity of
the menus to pull VFIO_PCI out of the if block and have it select
VFIO_PCI_CORE. Thanks,
Alex
