From 174178fed338edba66ab9580af0c5d9e1a4e5019 Mon Sep 17 00:00:00 2001 From: Eric Auger Date: Wed, 4 Mar 2015 11:14:36 +0100 Subject: [PATCH] KVM: arm/arm64: add irqfd support This patch enables irqfd on arm/arm64. Both irqfd and resamplefd are supported. Injection is implemented in vgic.c without routing. This patch enables CONFIG_HAVE_KVM_EVENTFD and CONFIG_HAVE_KVM_IRQFD. KVM_CAP_IRQFD is now advertised. KVM_CAP_IRQFD_RESAMPLE capability automatically is advertised as soon as CONFIG_HAVE_KVM_IRQFD is set. Irqfd injection is restricted to SPI. The rationale behind not supporting PPI irqfd injection is that any device using a PPI would be a private-to-the-CPU device (timer for instance), so its state would have to be context-switched along with the VCPU and would require in-kernel wiring anyhow. It is not a relevant use case for irqfds. Signed-off-by: Eric Auger Reviewed-by: Christoffer Dall Acked-by: Marc Zyngier Signed-off-by: Christoffer Dall --- Documentation/virtual/kvm/api.txt | 6 ++++- arch/arm/include/uapi/asm/kvm.h | 3 +++ arch/arm/kvm/Kconfig | 2 ++ arch/arm/kvm/Makefile | 2 +- arch/arm/kvm/arm.c | 1 + arch/arm64/include/uapi/asm/kvm.h | 3 +++ arch/arm64/kvm/Kconfig | 2 ++ arch/arm64/kvm/Makefile | 2 +- virt/kvm/arm/vgic.c | 48 +++++++++++++++++++++++++++++++++++++++ 9 files changed, 66 insertions(+), 3 deletions(-) diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index b112efc..b265d8e 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -2234,7 +2234,7 @@ into the hash PTE second double word). 4.75 KVM_IRQFD Capability: KVM_CAP_IRQFD -Architectures: x86 s390 +Architectures: x86 s390 arm arm64 Type: vm ioctl Parameters: struct kvm_irqfd (in) Returns: 0 on success, -1 on error @@ -2260,6 +2260,10 @@ Note that closing the resamplefd is not sufficient to disable the irqfd. The KVM_IRQFD_FLAG_RESAMPLE is only necessary on assignment and need not be specified with KVM_IRQFD_FLAG_DEASSIGN. +On ARM/ARM64, the gsi field in the kvm_irqfd struct specifies the Shared +Peripheral Interrupt (SPI) index, such that the GIC interrupt ID is +given by gsi + 32. + 4.76 KVM_PPC_ALLOCATE_HTAB Capability: KVM_CAP_PPC_ALLOC_HTAB diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h index 0db25bc..2499867 100644 --- a/arch/arm/include/uapi/asm/kvm.h +++ b/arch/arm/include/uapi/asm/kvm.h @@ -198,6 +198,9 @@ struct kvm_arch_memory_slot { /* Highest supported SPI, from VGIC_NR_IRQS */ #define KVM_ARM_IRQ_GIC_MAX 127 +/* One single KVM irqchip, ie. the VGIC */ +#define KVM_NR_IRQCHIPS 1 + /* PSCI interface */ #define KVM_PSCI_FN_BASE 0x95c1ba5e #define KVM_PSCI_FN(n) (KVM_PSCI_FN_BASE + (n)) diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig index 83a448e..f1f79d1 100644 --- a/arch/arm/kvm/Kconfig +++ b/arch/arm/kvm/Kconfig @@ -28,6 +28,8 @@ config KVM select KVM_GENERIC_DIRTYLOG_READ_PROTECT select SRCU select MMU_NOTIFIER + select HAVE_KVM_EVENTFD + select HAVE_KVM_IRQFD depends on ARM_VIRT_EXT && ARM_LPAE && ARM_ARCH_TIMER ---help--- Support hosting virtualized guest machines. diff --git a/arch/arm/kvm/Makefile b/arch/arm/kvm/Makefile index 60be7be..a093bf1 100644 --- a/arch/arm/kvm/Makefile +++ b/arch/arm/kvm/Makefile @@ -15,7 +15,7 @@ AFLAGS_init.o := -Wa,-march=armv7-a$(plus_virt) AFLAGS_interrupts.o := -Wa,-march=armv7-a$(plus_virt) KVM := ../../../virt/kvm -kvm-arm-y = $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o +kvm-arm-y = $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o obj-y += kvm-arm.o init.o interrupts.o obj-y += arm.o handle_exit.o guest.o mmu.o emulate.o reset.o diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 5e893eb..cc96619f 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -171,6 +171,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) int r; switch (ext) { case KVM_CAP_IRQCHIP: + case KVM_CAP_IRQFD: case KVM_CAP_DEVICE_CTRL: case KVM_CAP_USER_MEMORY: case KVM_CAP_SYNC_MMU: diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index 3ef77a4..c154c0b7 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -191,6 +191,9 @@ struct kvm_arch_memory_slot { /* Highest supported SPI, from VGIC_NR_IRQS */ #define KVM_ARM_IRQ_GIC_MAX 127 +/* One single KVM irqchip, ie. the VGIC */ +#define KVM_NR_IRQCHIPS 1 + /* PSCI interface */ #define KVM_PSCI_FN_BASE 0x95c1ba5e #define KVM_PSCI_FN(n) (KVM_PSCI_FN_BASE + (n)) diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig index 05f56ce..5105e29 100644 --- a/arch/arm64/kvm/Kconfig +++ b/arch/arm64/kvm/Kconfig @@ -28,6 +28,8 @@ config KVM select KVM_ARM_HOST select KVM_GENERIC_DIRTYLOG_READ_PROTECT select SRCU + select HAVE_KVM_EVENTFD + select HAVE_KVM_IRQFD ---help--- Support hosting virtualized guest machines. diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index c92b26a..b22c636 100644 --- a/arch/arm64/kvm/Makefile +++ b/arch/arm64/kvm/Makefile @@ -11,7 +11,7 @@ ARM=../../../arch/arm/kvm obj-$(CONFIG_KVM_ARM_HOST) += kvm.o -kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o +kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o kvm-$(CONFIG_KVM_ARM_HOST) += $(ARM)/arm.o $(ARM)/mmu.o $(ARM)/mmio.o kvm-$(CONFIG_KVM_ARM_HOST) += $(ARM)/psci.o $(ARM)/perf.o diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index 897c849..c000e97 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -31,6 +31,7 @@ #include #include #include +#include /* * How the whole thing works (courtesy of Christoffer Dall): @@ -1083,6 +1084,7 @@ static bool vgic_process_maintenance(struct kvm_vcpu *vcpu) u32 status = vgic_get_interrupt_status(vcpu); struct vgic_dist *dist = &vcpu->kvm->arch.vgic; bool level_pending = false; + struct kvm *kvm = vcpu->kvm; kvm_debug("STATUS = %08x\n", status); @@ -1118,6 +1120,17 @@ static bool vgic_process_maintenance(struct kvm_vcpu *vcpu) */ vgic_dist_irq_clear_soft_pend(vcpu, vlr.irq); + /* + * kvm_notify_acked_irq calls kvm_set_irq() + * to reset the IRQ level. Need to release the + * lock for kvm_set_irq to grab it. + */ + spin_unlock(&dist->lock); + + kvm_notify_acked_irq(kvm, 0, + vlr.irq - VGIC_NR_PRIVATE_IRQS); + spin_lock(&dist->lock); + /* Any additional pending interrupt? */ if (vgic_dist_irq_get_level(vcpu, vlr.irq)) { vgic_cpu_irq_set(vcpu, vlr.irq); @@ -1913,3 +1926,38 @@ out_free_irq: free_percpu_irq(vgic->maint_irq, kvm_get_running_vcpus()); return ret; } + +int kvm_irq_map_gsi(struct kvm *kvm, + struct kvm_kernel_irq_routing_entry *entries, + int gsi) +{ + return gsi; +} + +int kvm_irq_map_chip_pin(struct kvm *kvm, unsigned irqchip, unsigned pin) +{ + return pin; +} + +int kvm_set_irq(struct kvm *kvm, int irq_source_id, + u32 irq, int level, bool line_status) +{ + unsigned int spi = irq + VGIC_NR_PRIVATE_IRQS; + + trace_kvm_set_irq(irq, level, irq_source_id); + + BUG_ON(!vgic_initialized(kvm)); + + if (spi > kvm->arch.vgic.nr_irqs) + return -EINVAL; + return kvm_vgic_inject_irq(kvm, 0, spi, level); + +} + +/* MSI not implemented yet */ +int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e, + struct kvm *kvm, int irq_source_id, + int level, bool line_status) +{ + return 0; +} -- 2.7.4