On Tue, 2014-09-09 at 08:31 +0100, Eric Auger wrote:
> This RFC series aims at enabling KVM platform device passthrough.
> It implements a VFIO platform device, derived from VFIO PCI device.
>
> The VFIO platform device uses the host VFIO platform driver which must
> be bound to the assigned device prior to the QEMU system start.
>
> - the guest can directly access the device register space
> - assigned device IRQs are transparently routed to the guest by
> QEMU/KVM (3 methods currently are supported: user-level eventfd
> handling, irqfd, forwarded IRQs)
> - iommu is transparently programmed to prevent the device from
> accessing physical pages outside of the guest address space
>
> This patch series is made of the following patch files:
>
> 1-7) Modifications to PCI code to prepare for VFIO platform device
> 8) split of PCI specific code and generic code (move)
> 9-11) creation of the VFIO calxeda xgmac platform device, without irqfd
> support (MMIO direct access and IRQ assignment).
> 12) fake injection test modality (to test multiple IRQ)
> 13) addition of irqfd/virqfd support
> 14-16) forwarded IRQ
>
> Dependency List:
>
> QEMU dependencies:
> [1] [PATCH v2 0/9] Dynamic sysbus device allocation support, Alex Graf
> http://lists.gnu.org/archive/html/qemu-ppc/2014-07/msg00047.html
> [2] [RFC v3] machvirt dynamic sysbus device instantiation, Eric Auger
> [3] [PATCH v2 0/2] actual checks of KVM_CAP_IRQFD and KVM_CAP_IRQFD_RESAMPLE,
> Eric Auger
> http://lists.nongnu.org/archive/html/qemu-devel/2014-09/msg00589.html
> [4] [RFC] vfio: migration to trace points, Eric Auger
> http://lists.nongnu.org/archive/html/qemu-devel/2014-09/msg00569.html
>
> Kernel Dependencies:
> [5] [RFC Patch v6 0/20] VFIO support for platform devices, Antonios Motakis
> https://www.mail-archive.com/kvm@vger.kernel.org/msg103247.html
> [6] [PATCH v3] ARM: KVM: add irqfd support, Eric Auger
> https://lkml.org/lkml/2014/9/1/141
> [7] arm/arm64: KVM: Various VGIC cleanups and improvements, Christoffer Dall
> http://comments.gmane.org/gmane.linux.ports.arm.kernel/340430
> [8] [RFC v2 0/9] KVM-VFIO IRQ forward control, Eric Auger
> https://lkml.org/lkml/2014/9/1/344
> [9] [RFC PATCH 0/9] ARM: Forwarding physical interrupts to a guest VM,
> Marc Zyngier
> http://lwn.net/Articles/603514/
>
> kernel pieces can be found at:
> http://git.linaro.org/people/eric.auger/linux.git
> (branch 3.17rc3_irqfd_forward_integ_v2)
> QEMU pieces can be found at:
> http://git.linaro.org/people/eric.auger/qemu.git (branch vfio_integ_v6)
>
> The patch series was tested on Calxeda Midway (ARMv7) where one xgmac
> is assigned to KVM host while the second one is assigned to the guest.
> Reworked PCI device is not tested.
>
> Wiki for Calxeda Midway setup:
> https://wiki.linaro.org/LEG/Engineering/Virtualization/Platform_Device_Passthrough_on_Midway
>
> History:
>
> v5->v6:
> - rebase on 2.1rc5 PCI code
> - forwarded IRQ first integraton
Why? Are there acceleration paths that you're concerned cannot be
implemented or we do not already have a proof of concept for? The base
kernel patch series you depend on is 3 months old yet this series
continues to grow and add new dependencies. Please let's prioritize
getting something upstream instead of adding more blockers to prevent
that. Thanks,
Alex
> - vfio_device property renamed into host property
> - split IRQ setup in different functions that match the 3 supported
> injection techniques (user handled eventfd, irqfd, forwarded IRQ):
> removes dynamic switch between injection methods
> - introduce fake interrupts as a test modality:
> x makes possible to test multiple IRQ user-side handling.
> x this is a test feature only: enable to trigger a fd as if the
> real physical IRQ hit. No virtual IRQ is injected into the guest
> but handling is simulated so that the state machine can be tested
> - user handled eventfd:
> x add mutex to protect IRQ state & list manipulation,
> x correct misleading comment in vfio_intp_interrupt.
> x Fix bugs using fake interrupt modality
> - irqfd no more advertised in this patchset (handled in [3])
> - VFIOPlatformDeviceClass becomes abstract and Calxeda xgmac device
> and class is re-introduced (as per v4)
> - all DPRINTF removed in platform and replaced by trace-points
> - corrects compilation with configure --disable-kvm
> - simplifies the split for vfio_get_device and introduce a unique
> specialized function named vfio_populate_device
> - group_list renamed into vfio_group_list
> - hw/arm/dyn_sysbus_devtree.c currently only support vfio-calxeda-xgmac
> instantiation. Needs to be specialized for other VFIO devices
> - fix 2 bugs in dyn_sysbus_devtree(reg_attr index and compat)
>
> v4->v5:
> - rebase on v2.1.0 PCI code
> - take into account Alex Williamson comments on PCI code rework
> - trace updates in vfio_region_write/read
> - remove fd from VFIORegion
> - get/put ckeanup
> - bug fix: bar region's vbasedev field duly initialization
> - misc cleanups in platform device
> - device tree node generation removed from device and handled in
> hw/arm/dyn_sysbus_devtree.c
> - remove "hw/vfio: add an example calxeda_xgmac": with removal of
> device tree node generation we do not have so many things to
> implement in that derived device yet. May be re-introduced later
> on if needed typically for reset/migration.
> - no GSI routing table anymore
>
> v3->v4 changes (Eric Auger, Alvise Rigo)
> - rebase on last VFIO PCI code (v2.1.0-rc0)
> - full git history rework to ease PCI code change review
> - mv include files in hw/vfio
> - DPRINTF reformatting temporarily moved out
> - support of VFIO virq (removal of resamplefd handler on user-side)
> - integration with sysbus dynamic instantiation framwork
> - removal of unrealize and cleanup routines until it is better
> understood what is really needed
> - Support of VFIO for Amba devices should be handled in an inherited
> device to specialize the device tree generation (clock handle currently
> missing in framework however)
> - "Always use eventfd as notifying mechanism" temporarily moved out
> - static instantiation is not mainstream (although it remains possible)
> note if static instantiation is used, irqfd must be setup in machine file
> when virtual IRQ is known
> - create the GSI routing table on qemu side
>
> v2->v3 changes (Alvise Rigo, Eric Auger):
> - Following Alex W recommandations, further efforts to factorize the
> code between PCI:introduction of VFIODevice and VFIORegion
> as base classes
> - unique reset handler for platform and PCI
> - cleanup following Kim's comments
> - multiple IRQ support mechanics should be in place although not
> tested
> - Better handling of MMIO multiple regions
> - New features and fixes by Alvise (multiple compat string, exec
> flag, force eventfd usage, amba device tree support)
> - irqfd support
>
> v1->v2 changes (Kim Phillips, Eric Auger):
> - IRQ initial support (legacy mode where eventfds are handled on
> user side)
> - hacked dynamic instantiation
>
> v1 (Kim Phillips):
> - initial split between PCI and platform
> - MMIO support only
> - static instantiation
>
> Best Regards
>
> Eric
>
>
> Eric Auger (15):
> hw/vfio/pci: Rename VFIODevice into VFIOPCIDevice
> hw/vfio/pci: introduce VFIODevice
> hw/vfio/pci: Introduce VFIORegion
> hw/vfio/pci: split vfio_get_device
> hw/vfio/pci: rename group_list into vfio_group_list
> hw/vfio/pci: use name field in format strings
> hw/vfio: create common module
> hw/vfio/platform: add vfio-platform support
> hw/vfio: calxeda xgmac device
> hw/arm/dyn_sysbus_devtree: enable vfio-calxeda-xgmac dynamic
> instantiation
> vfio/platform: add fake injection modality
> hw/vfio/platform: Add irqfd support
> linux-headers: Update KVM headers from linux-next tag ToBeFilled
> VFIO: COMMON: vfio_kvm_device_fd moved in the common header
> VFIO: PLATFORM: add forwarded irq support
>
> Kim Phillips (1):
> vfio: move hw/misc/vfio.c to hw/vfio/pci.c Move vfio.h into
> include/hw/vfio
>
> LICENSE | 2 +-
> MAINTAINERS | 2 +-
> hw/Makefile.objs | 1 +
> hw/arm/dyn_sysbus_devtree.c | 141 +++
> hw/misc/Makefile.objs | 1 -
> hw/ppc/spapr_pci_vfio.c | 2 +-
> hw/vfio/Makefile.objs | 6 +
> hw/vfio/calxeda_xgmac.c | 57 ++
> hw/vfio/common.c | 959 +++++++++++++++++++
> hw/{misc/vfio.c => vfio/pci.c} | 1670
> +++++++---------------------------
> hw/vfio/platform.c | 874 ++++++++++++++++++
> include/hw/vfio/vfio-calxeda-xgmac.h | 41 +
> include/hw/vfio/vfio-common.h | 157 ++++
> include/hw/vfio/vfio-platform.h | 95 ++
> include/hw/{misc => vfio}/vfio.h | 0
> linux-headers/linux/kvm.h | 9 +
> trace-events | 136 +--
> 17 files changed, 2739 insertions(+), 1414 deletions(-)
> create mode 100644 hw/vfio/Makefile.objs
> create mode 100644 hw/vfio/calxeda_xgmac.c
> create mode 100644 hw/vfio/common.c
> rename hw/{misc/vfio.c => vfio/pci.c} (65%)
> create mode 100644 hw/vfio/platform.c
> create mode 100644 include/hw/vfio/vfio-calxeda-xgmac.h
> create mode 100644 include/hw/vfio/vfio-common.h
> create mode 100644 include/hw/vfio/vfio-platform.h
> rename include/hw/{misc => vfio}/vfio.h (100%)
>
