From 5863c2ce7269a7b24d60006430aa79a750b226ec Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 21 Jan 2013 19:36:15 -0500 Subject: [PATCH] ARM: KVM: VGIC interrupt injection Plug the interrupt injection code. Interrupts can now be generated from user space. Reviewed-by: Will Deacon Signed-off-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm/include/asm/kvm_vgic.h | 8 +++ arch/arm/kvm/arm.c | 55 ++++++++++++--- arch/arm/kvm/vgic.c | 117 ++++++++++++++++++++++++++++++++ 3 files changed, 170 insertions(+), 10 deletions(-) diff --git a/arch/arm/include/asm/kvm_vgic.h b/arch/arm/include/asm/kvm_vgic.h index c2dc8574ea3a..11a6d90899f7 100644 --- a/arch/arm/include/asm/kvm_vgic.h +++ b/arch/arm/include/asm/kvm_vgic.h @@ -147,6 +147,8 @@ struct kvm_exit_mmio; int kvm_vgic_set_addr(struct kvm *kvm, unsigned long type, u64 addr); void kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu); void kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu); +int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int irq_num, + bool level); int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu); bool vgic_handle_mmio(struct kvm_vcpu *vcpu, struct kvm_run *run, struct kvm_exit_mmio *mmio); @@ -182,6 +184,12 @@ static inline int kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu) static inline void kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu) {} static inline void kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu) {} +static inline int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, + unsigned int irq_num, bool level) +{ + return 0; +} + static inline int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu) { return 0; diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index c327fd9d8ec3..3c8d6a9be123 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -810,20 +810,49 @@ int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level) trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level); - if (irq_type != KVM_ARM_IRQ_TYPE_CPU) - return -EINVAL; + switch (irq_type) { + case KVM_ARM_IRQ_TYPE_CPU: + if (irqchip_in_kernel(kvm)) + return -ENXIO; - if (vcpu_idx >= nrcpus) - return -EINVAL; + if (vcpu_idx >= nrcpus) + return -EINVAL; - vcpu = kvm_get_vcpu(kvm, vcpu_idx); - if (!vcpu) - return -EINVAL; + vcpu = kvm_get_vcpu(kvm, vcpu_idx); + if (!vcpu) + return -EINVAL; - if (irq_num > KVM_ARM_IRQ_CPU_FIQ) - return -EINVAL; + if (irq_num > KVM_ARM_IRQ_CPU_FIQ) + return -EINVAL; + + return vcpu_interrupt_line(vcpu, irq_num, level); + case KVM_ARM_IRQ_TYPE_PPI: + if (!irqchip_in_kernel(kvm)) + return -ENXIO; + + if (vcpu_idx >= nrcpus) + return -EINVAL; + + vcpu = kvm_get_vcpu(kvm, vcpu_idx); + if (!vcpu) + return -EINVAL; + + if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS) + return -EINVAL; - return vcpu_interrupt_line(vcpu, irq_num, level); + return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level); + case KVM_ARM_IRQ_TYPE_SPI: + if (!irqchip_in_kernel(kvm)) + return -ENXIO; + + if (irq_num < VGIC_NR_PRIVATE_IRQS || + irq_num > KVM_ARM_IRQ_GIC_MAX) + return -EINVAL; + + return kvm_vgic_inject_irq(kvm, 0, irq_num, level); + } + + return -EINVAL; } long kvm_arch_vcpu_ioctl(struct file *filp, @@ -904,6 +933,12 @@ long kvm_arch_vm_ioctl(struct file *filp, void __user *argp = (void __user *)arg; switch (ioctl) { + case KVM_CREATE_IRQCHIP: { + if (vgic_present) + return kvm_vgic_create(kvm); + else + return -ENXIO; + } case KVM_ARM_SET_DEVICE_ADDR: { struct kvm_arm_device_addr dev_addr; diff --git a/arch/arm/kvm/vgic.c b/arch/arm/kvm/vgic.c index 2d5e29f1c28f..2e6a585c23e5 100644 --- a/arch/arm/kvm/vgic.c +++ b/arch/arm/kvm/vgic.c @@ -73,6 +73,7 @@ static void vgic_retire_disabled_irqs(struct kvm_vcpu *vcpu); static void vgic_update_state(struct kvm *kvm); +static void vgic_kick_vcpus(struct kvm *kvm); static void vgic_dispatch_sgi(struct kvm_vcpu *vcpu, u32 reg); static u32 *vgic_bitmap_get_reg(struct vgic_bitmap *x, @@ -708,6 +709,9 @@ bool vgic_handle_mmio(struct kvm_vcpu *vcpu, struct kvm_run *run, kvm_prepare_mmio(run, mmio); kvm_handle_mmio_return(vcpu, run); + if (updated_state) + vgic_kick_vcpus(vcpu->kvm); + return true; } @@ -1104,6 +1108,119 @@ int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu) return test_bit(vcpu->vcpu_id, &dist->irq_pending_on_cpu); } +static void vgic_kick_vcpus(struct kvm *kvm) +{ + struct kvm_vcpu *vcpu; + int c; + + /* + * We've injected an interrupt, time to find out who deserves + * a good kick... + */ + kvm_for_each_vcpu(c, vcpu, kvm) { + if (kvm_vgic_vcpu_pending_irq(vcpu)) + kvm_vcpu_kick(vcpu); + } +} + +static int vgic_validate_injection(struct kvm_vcpu *vcpu, int irq, int level) +{ + int is_edge = vgic_irq_is_edge(vcpu, irq); + int state = vgic_dist_irq_is_pending(vcpu, irq); + + /* + * Only inject an interrupt if: + * - edge triggered and we have a rising edge + * - level triggered and we change level + */ + if (is_edge) + return level > state; + else + return level != state; +} + +static bool vgic_update_irq_state(struct kvm *kvm, int cpuid, + unsigned int irq_num, bool level) +{ + struct vgic_dist *dist = &kvm->arch.vgic; + struct kvm_vcpu *vcpu; + int is_edge, is_level; + int enabled; + bool ret = true; + + spin_lock(&dist->lock); + + vcpu = kvm_get_vcpu(kvm, cpuid); + is_edge = vgic_irq_is_edge(vcpu, irq_num); + is_level = !is_edge; + + if (!vgic_validate_injection(vcpu, irq_num, level)) { + ret = false; + goto out; + } + + if (irq_num >= VGIC_NR_PRIVATE_IRQS) { + cpuid = dist->irq_spi_cpu[irq_num - VGIC_NR_PRIVATE_IRQS]; + vcpu = kvm_get_vcpu(kvm, cpuid); + } + + kvm_debug("Inject IRQ%d level %d CPU%d\n", irq_num, level, cpuid); + + if (level) + vgic_dist_irq_set(vcpu, irq_num); + else + vgic_dist_irq_clear(vcpu, irq_num); + + enabled = vgic_irq_is_enabled(vcpu, irq_num); + + if (!enabled) { + ret = false; + goto out; + } + + if (is_level && vgic_irq_is_active(vcpu, irq_num)) { + /* + * Level interrupt in progress, will be picked up + * when EOId. + */ + ret = false; + goto out; + } + + if (level) { + vgic_cpu_irq_set(vcpu, irq_num); + set_bit(cpuid, &dist->irq_pending_on_cpu); + } + +out: + spin_unlock(&dist->lock); + + return ret; +} + +/** + * kvm_vgic_inject_irq - Inject an IRQ from a device to the vgic + * @kvm: The VM structure pointer + * @cpuid: The CPU for PPIs + * @irq_num: The IRQ number that is assigned to the device + * @level: Edge-triggered: true: to trigger the interrupt + * false: to ignore the call + * Level-sensitive true: activates an interrupt + * false: deactivates an interrupt + * + * The GIC is not concerned with devices being active-LOW or active-HIGH for + * level-sensitive interrupts. You can think of the level parameter as 1 + * being HIGH and 0 being LOW and all devices being active-HIGH. + */ +int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int irq_num, + bool level) +{ + if (vgic_update_irq_state(kvm, cpuid, irq_num, level)) + vgic_kick_vcpus(kvm); + + return 0; +} + static bool vgic_ioaddr_overlap(struct kvm *kvm) { phys_addr_t dist = kvm->arch.vgic.vgic_dist_base; -- 2.30.2