This patchset implements the KVM part of the synthetic interrupt controller (SynIC) which is a building block of the Hyper-V paravirtualized device bus (vmbus). SynIC is a lapic extension, which is controlled via MSRs and maintains for each vCPU - 16 synthetic interrupt "lines" (SINT's); each can be configured to trigger a specific interrupt vector optionally with auto-EOI semantics - a message page in the guest memory with 16 256-byte per-SINT message slots - an event flag page in the guest memory with 16 2048-bit per-SINT event flag areas The host triggers a SINT whenever it delivers a new message to the corresponding slot or flips an event flag bit in the corresponding area. The guest informs the host that it can try delivering a message by explicitly asserting EOI in lapic or writing to End-Of-Message (EOM) MSR. The userspace (qemu) triggers interrupts and receives EOM notifications via irqfd with resampler; for that, a GSI is allocated for each configured SINT, and irq_routing api is extended to support GSI-SINT mapping. Besides, a new vcpu exit is introduced to notify the userspace of the changes in SynIC configuraion triggered by guest writing to the corresponding MSRs. Signed-off-by: Andrey Smetanin <asmetanin@xxxxxxxxxxxxx> Reviewed-by: Roman Kagan <rkagan@xxxxxxxxxxxxx> Signed-off-by: Denis V. Lunev <den@xxxxxxxxxx> CC: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> CC: "K. Y. Srinivasan" <kys@xxxxxxxxxxxxx> CC: Gleb Natapov <gleb@xxxxxxxxxx> CC: Paolo Bonzini <pbonzini@xxxxxxxxxx> Changes v2: * irqchip/eventfd preparation improvements to support arch specific routing entries like Hyper-V SynIC ones. * add Hyper-V SynIC vectors into EOI exit bitmap. * do not use posted interrupts in case of Hyper-V SynIC AutoEOI vectors -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
