Userspace can inject IRQs and FIQs through the KVM_IRQ_LINE VM ioctl. This ioctl is used since the sematics are in fact two lines that can be either raised or lowered on the VCPU - the IRQ and FIQ lines.
KVM needs to know which VCPU it must operate on and whether the FIQ or IRQ line is raised/lowered. Hence both pieces of information is packed in the kvm_irq_level->irq field. The irq fild value will be: IRQ: vcpu_index * 2 FIQ: (vcpu_index * 2) + 1 This is documented in Documentation/kvm/api.txt. The effect of the ioctl is simply to simply raise/lower the corresponding virt_irq field on the VCPU struct, which will cause the world-switch code to raise/lower virtual interrupts when running the guest on next switch. The wait_for_interrupt flag is also cleared for raised IRQs causing an idle VCPU to become active again. Signed-off-by: Christoffer Dall <[email protected]> --- Documentation/kvm/api.txt | 11 ++++++-- arch/arm/include/asm/kvm.h | 8 ++++++ arch/arm/include/asm/kvm_arm.h | 1 + arch/arm/kvm/arm.c | 54 +++++++++++++++++++++++++++++++++++++++- arch/arm/kvm/trace.h | 21 ++++++++++++++++ include/linux/kvm.h | 1 + 6 files changed, 91 insertions(+), 5 deletions(-) diff --git a/Documentation/kvm/api.txt b/Documentation/kvm/api.txt index 9bef4e4..1ed5554 100644 --- a/Documentation/kvm/api.txt +++ b/Documentation/kvm/api.txt @@ -534,15 +534,20 @@ only go to the IOAPIC. On ia64, a IOSAPIC is created. 4.25 KVM_IRQ_LINE Capability: KVM_CAP_IRQCHIP -Architectures: x86, ia64 +Architectures: x86, ia64, arm Type: vm ioctl Parameters: struct kvm_irq_level Returns: 0 on success, -1 on error Sets the level of a GSI input to the interrupt controller model in the kernel. Requires that an interrupt controller model has been previously created with -KVM_CREATE_IRQCHIP. Note that edge-triggered interrupts require the level -to be set to 1 and then back to 0. +KVM_CREATE_IRQCHIP (except for ARM). Note that edge-triggered interrupts +require the level to be set to 1 and then back to 0. + +ARM uses two types of interrupt lines per CPU, ie. IRQ and FIQ. The value of the +irq field should be (VCPU_INDEX * 2) for IRQs and ((VCPU_INDEX * 2) + 1) for +FIQs. Level is used to raise/lower the line. See arch/arm/include/asm/kvm.h for +convenience macros. struct kvm_irq_level { union { diff --git a/arch/arm/include/asm/kvm.h b/arch/arm/include/asm/kvm.h index 87dc33b..8935062 100644 --- a/arch/arm/include/asm/kvm.h +++ b/arch/arm/include/asm/kvm.h @@ -20,6 +20,14 @@ #include <asm/types.h> /* + * KVM_IRQ_LINE macros to set/read IRQ/FIQ for specific VCPU index. + */ +enum KVM_ARM_IRQ_LINE_TYPE { + KVM_ARM_IRQ_LINE = 0, + KVM_ARM_FIQ_LINE = 1, +}; + +/* * Modes used for short-hand mode determinition in the world-switch code and * in emulation code. * diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h index 835abd1..e378a37 100644 --- a/arch/arm/include/asm/kvm_arm.h +++ b/arch/arm/include/asm/kvm_arm.h @@ -49,6 +49,7 @@ #define HCR_VM 1 #define HCR_GUEST_MASK (HCR_TSC | HCR_TWE | HCR_TWI | HCR_VM | HCR_AMO | \ HCR_AMO | HCR_IMO | HCR_FMO | HCR_SWIO) +#define HCR_VIRT_EXCP_MASK (HCR_VA | HCR_VI | HCR_VF) /* Hyp System Control Register (HSCTLR) bits */ #define HSCTLR_TE (1 << 30) diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 3db6794..071912e 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -297,6 +297,43 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) return -EINVAL; } +static int kvm_arch_vm_ioctl_irq_line(struct kvm *kvm, + struct kvm_irq_level *irq_level) +{ + u32 mask; + unsigned int vcpu_idx; + struct kvm_vcpu *vcpu; + + vcpu_idx = irq_level->irq / 2; + if (vcpu_idx >= KVM_MAX_VCPUS) + return -EINVAL; + + vcpu = kvm_get_vcpu(kvm, vcpu_idx); + if (!vcpu) + return -EINVAL; + + switch (irq_level->irq % 2) { + case KVM_ARM_IRQ_LINE: + mask = HCR_VI; + break; + case KVM_ARM_FIQ_LINE: + mask = HCR_VF; + break; + default: + return -EINVAL; + } + + trace_kvm_irq_line(irq_level->irq % 2, irq_level->level, vcpu_idx); + + if (irq_level->level) { + vcpu->arch.virt_irq |= mask; + vcpu->arch.wait_for_interrupts = 0; + } else + vcpu->arch.virt_irq &= ~mask; + + return 0; +} + long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) { @@ -312,8 +349,21 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log) long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) { - printk(KERN_ERR "kvm_arch_vm_ioctl: Unsupported ioctl (%d)\n", ioctl); - return -EINVAL; + struct kvm *kvm = filp->private_data; + void __user *argp = (void __user *)arg; + + switch (ioctl) { + case KVM_IRQ_LINE: { + struct kvm_irq_level irq_event; + + if (copy_from_user(&irq_event, argp, sizeof irq_event)) + return -EFAULT; + return kvm_arch_vm_ioctl_irq_line(kvm, &irq_event); + } + default: + kvm_err(-EINVAL, "Unsupported ioctl (%d)", ioctl); + return -EINVAL; + } } /** diff --git a/arch/arm/kvm/trace.h b/arch/arm/kvm/trace.h index f8869c1..ac64e3a 100644 --- a/arch/arm/kvm/trace.h +++ b/arch/arm/kvm/trace.h @@ -40,6 +40,27 @@ TRACE_EVENT(kvm_exit, ); +TRACE_EVENT(kvm_irq_line, + TP_PROTO(unsigned int type, unsigned int level, unsigned int vcpu_idx), + TP_ARGS(type, level, vcpu_idx), + + TP_STRUCT__entry( + __field( unsigned int, type ) + __field( unsigned int, level ) + __field( unsigned int, vcpu_idx ) + ), + + TP_fast_assign( + __entry->type = type; + __entry->level = level; + __entry->vcpu_idx = vcpu_idx; + ), + + TP_printk("KVM_IRQ_LINE: type: %s, level: %u, vcpu: %u", + (__entry->type == KVM_ARM_IRQ_LINE) ? "IRQ" : "FIQ", + __entry->level, __entry->vcpu_idx) +); + #endif /* _TRACE_KVM_H */ diff --git a/include/linux/kvm.h b/include/linux/kvm.h index ea2dc1a..4e85b4a 100644 --- a/include/linux/kvm.h +++ b/include/linux/kvm.h @@ -111,6 +111,7 @@ struct kvm_irq_level { * ACPI gsi notion of irq. * For IA-64 (APIC model) IOAPIC0: irq 0-23; IOAPIC1: irq 24-47.. * For X86 (standard AT mode) PIC0/1: irq 0-15. IOAPIC0: 0-23.. + * For ARM: IRQ: irq = (2*vcpu_index). FIQ: irq = (2*vcpu_indx + 1). */ union { __u32 irq; -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
