From 96ad2cc6132479aa0aea485d0838a13fda765bd5 Mon Sep 17 00:00:00 2001 From: Eddie Dong Date: Thu, 6 Sep 2007 12:22:56 +0300 Subject: [PATCH] KVM: in-kernel LAPIC save and restore support This patch adds a new vcpu-based IOCTL to save and restore the local apic registers for a single vcpu. The kernel only copies the apic page as a whole, extraction of registers is left to userspace side. On restore, the APIC timer is restarted from the initial count, this introduces a little delay, but works fine. Signed-off-by: Yaozu (Eddie) Dong Signed-off-by: Qing He Signed-off-by: Avi Kivity --- drivers/kvm/irq.h | 1 + drivers/kvm/kvm_main.c | 46 ++++++++++++++++++++++++++++++++++++++++++ drivers/kvm/lapic.c | 13 ++++++++++++ include/linux/kvm.h | 8 ++++++++ 4 files changed, 68 insertions(+) diff --git a/drivers/kvm/irq.h b/drivers/kvm/irq.h index 30adddcb18..24b871f9b5 100644 --- a/drivers/kvm/irq.h +++ b/drivers/kvm/irq.h @@ -149,6 +149,7 @@ int kvm_apic_match_physical_addr(struct kvm_lapic *apic, u16 dest); void kvm_ioapic_update_eoi(struct kvm *kvm, int vector); int kvm_apic_match_logical_addr(struct kvm_lapic *apic, u8 mda); int kvm_apic_set_irq(struct kvm_lapic *apic, u8 vec, u8 trig); +void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu); int kvm_ioapic_init(struct kvm *kvm); void kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int level); diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c index 61dff55f13..a012d70d9e 100644 --- a/drivers/kvm/kvm_main.c +++ b/drivers/kvm/kvm_main.c @@ -2642,6 +2642,27 @@ static int kvm_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu) return 0; } +static int kvm_vcpu_ioctl_get_lapic(struct kvm_vcpu *vcpu, + struct kvm_lapic_state *s) +{ + vcpu_load(vcpu); + memcpy(s->regs, vcpu->apic->regs, sizeof *s); + vcpu_put(vcpu); + + return 0; +} + +static int kvm_vcpu_ioctl_set_lapic(struct kvm_vcpu *vcpu, + struct kvm_lapic_state *s) +{ + vcpu_load(vcpu); + memcpy(vcpu->apic->regs, s->regs, sizeof *s); + kvm_apic_post_state_restore(vcpu); + vcpu_put(vcpu); + + return 0; +} + static long kvm_vcpu_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) { @@ -2811,6 +2832,31 @@ static long kvm_vcpu_ioctl(struct file *filp, r = 0; break; } + case KVM_GET_LAPIC: { + struct kvm_lapic_state lapic; + + memset(&lapic, 0, sizeof lapic); + r = kvm_vcpu_ioctl_get_lapic(vcpu, &lapic); + if (r) + goto out; + r = -EFAULT; + if (copy_to_user(argp, &lapic, sizeof lapic)) + goto out; + r = 0; + break; + } + case KVM_SET_LAPIC: { + struct kvm_lapic_state lapic; + + r = -EFAULT; + if (copy_from_user(&lapic, argp, sizeof lapic)) + goto out; + r = kvm_vcpu_ioctl_set_lapic(vcpu, &lapic);; + if (r) + goto out; + r = 0; + break; + } default: ; } diff --git a/drivers/kvm/lapic.c b/drivers/kvm/lapic.c index 4b5c77d890..df636bf197 100644 --- a/drivers/kvm/lapic.c +++ b/drivers/kvm/lapic.c @@ -931,3 +931,16 @@ int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu) apic_clear_irr(vector, apic); return vector; } + +void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu) +{ + struct kvm_lapic *apic = vcpu->apic; + + apic->base_address = vcpu->apic_base & + MSR_IA32_APICBASE_BASE; + apic_set_reg(apic, APIC_LVR, APIC_VERSION); + apic_update_ppr(apic); + hrtimer_cancel(&apic->timer.dev); + update_divide_count(apic); + start_apic_timer(apic); +} diff --git a/include/linux/kvm.h b/include/linux/kvm.h index 42d15150d7..30a8369690 100644 --- a/include/linux/kvm.h +++ b/include/linux/kvm.h @@ -208,6 +208,12 @@ struct kvm_fpu { __u32 pad2; }; +/* for KVM_GET_LAPIC and KVM_SET_LAPIC */ +#define KVM_APIC_REG_SIZE 0x400 +struct kvm_lapic_state { + char regs[KVM_APIC_REG_SIZE]; +}; + struct kvm_segment { __u64 base; __u32 limit; @@ -380,5 +386,7 @@ struct kvm_signal_mask { #define KVM_SET_SIGNAL_MASK _IOW(KVMIO, 0x8b, struct kvm_signal_mask) #define KVM_GET_FPU _IOR(KVMIO, 0x8c, struct kvm_fpu) #define KVM_SET_FPU _IOW(KVMIO, 0x8d, struct kvm_fpu) +#define KVM_GET_LAPIC _IOR(KVMIO, 0x8e, struct kvm_lapic_state) +#define KVM_SET_LAPIC _IOW(KVMIO, 0x8f, struct kvm_lapic_state) #endif -- 2.39.5