| Message ID | 20210721161609.68223-1-yishaih@nvidia.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | Introduce vfio_pci_core subsystem | expand |
On 7/21/2021 7:15 PM, Yishai Hadas wrote: > Prologue: > > This is the second series of three to send the "mlx5_vfio_pci" driver > that has been discussed on the list for a while now. It comes on top of > the first series (i.e. Reorganize reflck to support splitting vfio_pci) > that was sent already and pending merge [1]. > > - Split vfio_pci into vfio_pci/vfio_pci_core and provide infrastructure > for non-generic VFIO PCI drivers. > - The new driver mlx5_vfio_pci that is a full implementation of > suspend/resume functionality for mlx5 devices. > > A preview of all the patches can be seen here: > https://github.com/jgunthorpe/linux/commits/mlx5_vfio_pci > > [1] https://lore.kernel.org/dri-devel/0-v2-b6a5582525c9+ff96-vfio_reflck_jgg@nvidia.com/T/#t > ===================== > > From Max Gurtovoy: > ==================== > This series splits the vfio_pci driver into two parts, a PCI driver and > a subsystem driver that will also be library of code. The main PCI > driver, vfio_pci.ko, will remain as before and it will use the library > module vfio_pci_core.ko to help create the vfio_device. > > This series is intended to solve the issues that were raised in the > previous attempts for extending vfio-pci for device specific > functionality: > > 1. https://lore.kernel.org/kvm/20200518024202.13996-1-yan.y.zhao@intel.com > by Yan Zhao > 2. https://lore.kernel.org/kvm/20210702095849.1610-1-shameerali.kolothum.thodi@huawei.com > by Longfang Liu > > Also to support proposed future changes to virtio and other common > protocols to support migration: > > https://lists.oasis-open.org/archives/virtio-comment/202106/msg00044.html > > This subsystem framework will also ease adding new device specific > functionality to VFIO devices in the future by allowing another module > to provide the pci_driver that can setup a number of details before > registering to the VFIO subsystem, such as injecting its own operations. > > This series also extends the "driver_override" mechanism. A flag is > added for PCI drivers that will declare themselves as "driver_override" > capable which sends their match table to the modules.alias file but > otherwise leaves them outside of the normal driver core auto-binding > world, like vfio_pci. > > In order to get the best match for "driver_override" drivers, one can > create a userspace program to inspect the modules.alias, an example can > be found at: > > https://github.com/maxgurtovoy/linux_tools/blob/main/vfio/bind_vfio_pci_driver.py > > Which finds the 'best match' according to a simple algorithm: "the > driver with the fewest '*' matches wins." > > For example, the vfio-pci driver will match to any pci device. So it > will have the maximal '*' matches. > > In case we are looking for a match to a mlx5 based device, we'll have a > match to vfio-pci.ko and mlx5-vfio-pci.ko. We'll prefer mlx5-vfio-pci.ko > since it will have less '*' matches (probably vendor and device IDs will > match). This will work in the future for NVMe/Virtio devices that can > match according to a class code or other criteria. > > Yishai > > > Jason Gunthorpe (2): > vfio: Use select for eventfd > vfio: Use kconfig if XX/endif blocks instead of repeating 'depends on' > > Max Gurtovoy (9): > vfio/pci: Rename vfio_pci.c to vfio_pci_core.c > vfio/pci: Rename vfio_pci_private.h to vfio_pci_core.h > vfio/pci: Rename vfio_pci_device to vfio_pci_core_device > vfio/pci: Rename ops functions to fit core namings > vfio/pci: Include vfio header in vfio_pci_core.h > vfio/pci: Split the pci_driver code out of vfio_pci_core.c > vfio/pci: Move igd initialization to vfio_pci.c > PCI: Add a PCI_ID_F_VFIO_DRIVER_OVERRIDE flag to struct pci_device_id > vfio/pci: Introduce vfio_pci_core.ko > > Yishai Hadas (1): > vfio/pci: Move module parameters to vfio_pci.c > > Documentation/PCI/pci.rst | 1 + > drivers/pci/pci-driver.c | 25 +- > drivers/vfio/Kconfig | 29 +- > drivers/vfio/fsl-mc/Kconfig | 3 +- > drivers/vfio/mdev/Kconfig | 1 - > drivers/vfio/pci/Kconfig | 39 +- > drivers/vfio/pci/Makefile | 8 +- > drivers/vfio/pci/vfio_pci.c | 2238 +---------------- > drivers/vfio/pci/vfio_pci_config.c | 70 +- > drivers/vfio/pci/vfio_pci_core.c | 2138 ++++++++++++++++ > drivers/vfio/pci/vfio_pci_igd.c | 19 +- > drivers/vfio/pci/vfio_pci_intrs.c | 42 +- > drivers/vfio/pci/vfio_pci_rdwr.c | 18 +- > drivers/vfio/pci/vfio_pci_zdev.c | 4 +- > drivers/vfio/platform/Kconfig | 6 +- > drivers/vfio/platform/reset/Kconfig | 4 +- > include/linux/mod_devicetable.h | 7 + > include/linux/pci.h | 27 + > .../linux/vfio_pci_core.h | 89 +- > scripts/mod/devicetable-offsets.c | 1 + > scripts/mod/file2alias.c | 8 +- > 21 files changed, 2496 insertions(+), 2281 deletions(-) > create mode 100644 drivers/vfio/pci/vfio_pci_core.c > rename drivers/vfio/pci/vfio_pci_private.h => include/linux/vfio_pci_core.h (56%) > Hi Alex, Based on the feedback that we got so far on this series, no functional changes are expected in V2. It may include the below minor changes: - Drop DRIVER_VERSION as it's useless and not required any more. (Patches #6, #12). - Add the sequence of commands/algorithm that is required by userspace to discover the matching driver to the commit message of patch #9. Do we need to wait for more feedback or that we are fine to send V2 ? Yishai
On Wed, 4 Aug 2021 16:41:34 +0300 Yishai Hadas <yishaih@nvidia.com> wrote: > On 7/21/2021 7:15 PM, Yishai Hadas wrote: > > Prologue: > > > > This is the second series of three to send the "mlx5_vfio_pci" driver > > that has been discussed on the list for a while now. It comes on top of > > the first series (i.e. Reorganize reflck to support splitting vfio_pci) > > that was sent already and pending merge [1]. > > > > - Split vfio_pci into vfio_pci/vfio_pci_core and provide infrastructure > > for non-generic VFIO PCI drivers. > > - The new driver mlx5_vfio_pci that is a full implementation of > > suspend/resume functionality for mlx5 devices. > > > > A preview of all the patches can be seen here: > > https://github.com/jgunthorpe/linux/commits/mlx5_vfio_pci > > > > [1] https://lore.kernel.org/dri-devel/0-v2-b6a5582525c9+ff96-vfio_reflck_jgg@nvidia.com/T/#t > > ===================== > > > > From Max Gurtovoy: > > ==================== > > This series splits the vfio_pci driver into two parts, a PCI driver and > > a subsystem driver that will also be library of code. The main PCI > > driver, vfio_pci.ko, will remain as before and it will use the library > > module vfio_pci_core.ko to help create the vfio_device. > > > > This series is intended to solve the issues that were raised in the > > previous attempts for extending vfio-pci for device specific > > functionality: > > > > 1. https://lore.kernel.org/kvm/20200518024202.13996-1-yan.y.zhao@intel.com > > by Yan Zhao > > 2. https://lore.kernel.org/kvm/20210702095849.1610-1-shameerali.kolothum.thodi@huawei.com > > by Longfang Liu > > > > Also to support proposed future changes to virtio and other common > > protocols to support migration: > > > > https://lists.oasis-open.org/archives/virtio-comment/202106/msg00044.html > > > > This subsystem framework will also ease adding new device specific > > functionality to VFIO devices in the future by allowing another module > > to provide the pci_driver that can setup a number of details before > > registering to the VFIO subsystem, such as injecting its own operations. > > > > This series also extends the "driver_override" mechanism. A flag is > > added for PCI drivers that will declare themselves as "driver_override" > > capable which sends their match table to the modules.alias file but > > otherwise leaves them outside of the normal driver core auto-binding > > world, like vfio_pci. > > > > In order to get the best match for "driver_override" drivers, one can > > create a userspace program to inspect the modules.alias, an example can > > be found at: > > > > https://github.com/maxgurtovoy/linux_tools/blob/main/vfio/bind_vfio_pci_driver.py > > > > Which finds the 'best match' according to a simple algorithm: "the > > driver with the fewest '*' matches wins." > > > > For example, the vfio-pci driver will match to any pci device. So it > > will have the maximal '*' matches. > > > > In case we are looking for a match to a mlx5 based device, we'll have a > > match to vfio-pci.ko and mlx5-vfio-pci.ko. We'll prefer mlx5-vfio-pci.ko > > since it will have less '*' matches (probably vendor and device IDs will > > match). This will work in the future for NVMe/Virtio devices that can > > match according to a class code or other criteria. > > > > Yishai > > > > > > Jason Gunthorpe (2): > > vfio: Use select for eventfd > > vfio: Use kconfig if XX/endif blocks instead of repeating 'depends on' > > > > Max Gurtovoy (9): > > vfio/pci: Rename vfio_pci.c to vfio_pci_core.c > > vfio/pci: Rename vfio_pci_private.h to vfio_pci_core.h > > vfio/pci: Rename vfio_pci_device to vfio_pci_core_device > > vfio/pci: Rename ops functions to fit core namings > > vfio/pci: Include vfio header in vfio_pci_core.h > > vfio/pci: Split the pci_driver code out of vfio_pci_core.c > > vfio/pci: Move igd initialization to vfio_pci.c > > PCI: Add a PCI_ID_F_VFIO_DRIVER_OVERRIDE flag to struct pci_device_id > > vfio/pci: Introduce vfio_pci_core.ko > > > > Yishai Hadas (1): > > vfio/pci: Move module parameters to vfio_pci.c > > > > Documentation/PCI/pci.rst | 1 + > > drivers/pci/pci-driver.c | 25 +- > > drivers/vfio/Kconfig | 29 +- > > drivers/vfio/fsl-mc/Kconfig | 3 +- > > drivers/vfio/mdev/Kconfig | 1 - > > drivers/vfio/pci/Kconfig | 39 +- > > drivers/vfio/pci/Makefile | 8 +- > > drivers/vfio/pci/vfio_pci.c | 2238 +---------------- > > drivers/vfio/pci/vfio_pci_config.c | 70 +- > > drivers/vfio/pci/vfio_pci_core.c | 2138 ++++++++++++++++ > > drivers/vfio/pci/vfio_pci_igd.c | 19 +- > > drivers/vfio/pci/vfio_pci_intrs.c | 42 +- > > drivers/vfio/pci/vfio_pci_rdwr.c | 18 +- > > drivers/vfio/pci/vfio_pci_zdev.c | 4 +- > > drivers/vfio/platform/Kconfig | 6 +- > > drivers/vfio/platform/reset/Kconfig | 4 +- > > include/linux/mod_devicetable.h | 7 + > > include/linux/pci.h | 27 + > > .../linux/vfio_pci_core.h | 89 +- > > scripts/mod/devicetable-offsets.c | 1 + > > scripts/mod/file2alias.c | 8 +- > > 21 files changed, 2496 insertions(+), 2281 deletions(-) > > create mode 100644 drivers/vfio/pci/vfio_pci_core.c > > rename drivers/vfio/pci/vfio_pci_private.h => include/linux/vfio_pci_core.h (56%) > > > Hi Alex, > > Based on the feedback that we got so far on this series, no functional > changes are expected in V2. > > It may include the below minor changes: > > - Drop DRIVER_VERSION as it's useless and not required any more. > (Patches #6, #12). > > - Add the sequence of commands/algorithm that is required by userspace > to discover the matching driver to the commit message of patch #9. > > Do we need to wait for more feedback or that we are fine to send V2 ? - Resolve Kconfig compatibility in patch 12 Patch 9 also depends on an ack from Bjorn, so whether you want to try to get his buy-in before or after that patch gets updated to clarify what it's trying to do and why, is up to you. Thanks, Alex