[PATCH v3 0/7] KVM: arm/arm64: gsi routing support

[Pavel Fedin]

Tested-by: Pavel Fedin <p.fedin at samsung.com>

Kind regards,
Pavel Fedin
Expert Engineer
Samsung Electronics Research center Russia

> -----Original Message-----
> From: Eric Auger [mailto:eric.auger at linaro.org]
> Sent: Monday, August 03, 2015 6:31 PM
> To: eric.auger at st.com; eric.auger at linaro.org; linux-arm-kernel at lists.infradead.org;
> kvmarm at lists.cs.columbia.edu; kvm at vger.kernel.org; christoffer.dall at linaro.org;
> marc.zyngier at arm.com
> Cc: linux-kernel at vger.kernel.org; patches at linaro.org; pbonzini at redhat.com;
> andre.przywara at arm.com; p.fedin at samsung.com
> Subject: [PATCH v3 0/7] KVM: arm/arm64: gsi routing support
> 
> With the advent of GICv3 ITS in-kernel emulation, KVM GSI routing
> appears to be requested. More specifically MSI routing is needed.
> irqchip routing does not sound to be really useful on arm but usage of
> MSI routing also mandates to integrate irqchip routing. The initial
> implementation of irqfd on arm must be upgraded with the integration
> of kvm irqchip.c code and the implementation of its standard hooks
> in the architecture specific part.
> 
> In case KVM_SET_GSI_ROUTING ioctl is not called, a default routing
> table with flat irqchip routing entries is built enabling to inject gsi
> corresponding to the SPI indexes seen by the guest.
> 
> As soon as KVM_SET_GSI_ROUTING is called, user-space overwrites this
> default routing table and is responsible for building the whole routing
> table.
> 
> for arm/arm64 KVM_SET_GSI_ROUTING has a limited support:
> - only applies to KVM_IRQFD and not to KVM_IRQ_LINE
> 
> - irqchip routing was tested on Calxeda midway (VFIO with irqfd)
>   with and without explicit routing
> - MSI routing without GICv3 ITS was tested using APM Xgene-I
>   (qemu VIRTIO-PCI vhost-net without gsi_direct_mapping).
> - MSI routing with GICv3 ITS is *NOT* tested.
> 
> Code can be found at
https://git.linaro.org/people/eric.auger/linux.git/shortlog/refs/heads/v4.2-rc4-
> gsi-routing-v3
> 
> It applies on Andre's [PATCH v2 00/15] KVM: arm64: GICv3 ITS emulation
> (http://lists.infradead.org/pipermail/linux-arm-kernel/2015-July/355727.html)
> 
> History:
> v2 -> v3:
> - eventually got rid of KVM_IRQ_ROUTING_EXTENDED_MSI new type at user
>   api level and use KVM_MSI_VALID_DEVID flag instead
> - remove usage of KVM_IRQ_ROUTING_EXTENDED_MSI type at kernel level too.
> - propagate user flags downto the kernel to make sure the userspace
>   correctly set devid in GICv3 ITS case (still under discussion)
> 
> v1 -> v2:
> - user API changed:
>   x devid id passed in kvm_irq_routing_msi
>   x kept the new routing entry type: KVM_IRQ_ROUTING_EXTENDED_MSI
> - kvm_host.h: adopt Andre's proposal to replace the msi_msg by a struct
>   composed of the msi_msg and devid in kvm_kernel_irq_routing_entry
> - Fix bug reported by Pavel: Added KVM_IRQ_ROUTING_EXTENDED_MSI handling
>   in eventfd.c
> - added vgic_v2m_inject_msi in vgic-v2-emul.c as suggested by Andre
> - fix bug reported by Andre: bad setting of msi.flags and msi.devid
>   in kvm_send_userspace_msi
> - avoid injecting reserved IRQ numbers in vgic_irqfd_set_irq
> 
> RFC -> PATCH:
> - clearly state limited support on arm/arm64:
>   KVM_IRQ_LINE not impacted by GSI routing
> - add default routing table feature (new patch file)
> - changed uapi to use padding field area
> - reword api.txt
> 
> Eric Auger (7):
>   KVM: api: pass the devid in the msi routing entry
>   KVM: kvm_host: add devid in kvm_kernel_irq_routing_entry
>   KVM: irqchip: convey devid to kvm_set_msi
>   KVM: arm/arm64: enable irqchip routing
>   KVM: arm/arm64: build a default routing table
>   KVM: arm/arm64: enable MSI routing
>   KVM: arm: enable KVM_SIGNAL_MSI and MSI routing
> 
>  Documentation/virtual/kvm/api.txt |  35 ++++++++++---
>  arch/arm/include/asm/kvm_host.h   |   2 +
>  arch/arm/kvm/Kconfig              |   3 ++
>  arch/arm/kvm/Makefile             |   2 +-
>  arch/arm64/include/asm/kvm_host.h |   1 +
>  arch/arm64/kvm/Kconfig            |   2 +
>  arch/arm64/kvm/Makefile           |   2 +-
>  include/kvm/arm_vgic.h            |   2 -
>  include/linux/kvm_host.h          |   8 ++-
>  include/uapi/linux/kvm.h          |   5 +-
>  virt/kvm/arm/vgic-v2-emul.c       |  16 ++++++
>  virt/kvm/arm/vgic.c               | 107 ++++++++++++++++++++++++++++++--------
>  virt/kvm/irqchip.c                |   8 ++-
>  13 files changed, 158 insertions(+), 35 deletions(-)
> 
> --
> 1.9.1