diff options
Diffstat (limited to 'drivers/kvm/svm.c')
-rw-r--r-- | drivers/kvm/svm.c | 94 |
1 files changed, 87 insertions, 7 deletions
diff --git a/drivers/kvm/svm.c b/drivers/kvm/svm.c index fa042873571..855207a9b39 100644 --- a/drivers/kvm/svm.c +++ b/drivers/kvm/svm.c @@ -235,6 +235,8 @@ static void skip_emulated_instruction(struct kvm_vcpu *vcpu) vcpu->rip = vcpu->svm->vmcb->save.rip = vcpu->svm->next_rip; vcpu->svm->vmcb->control.int_state &= ~SVM_INTERRUPT_SHADOW_MASK; + + vcpu->interrupt_window_open = 1; } static int has_svm(void) @@ -1031,10 +1033,11 @@ static int halt_interception(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) { vcpu->svm->next_rip = vcpu->svm->vmcb->save.rip + 1; skip_emulated_instruction(vcpu); - if (vcpu->irq_summary && (vcpu->svm->vmcb->save.rflags & X86_EFLAGS_IF)) + if (vcpu->irq_summary) return 1; kvm_run->exit_reason = KVM_EXIT_HLT; + ++kvm_stat.halt_exits; return 0; } @@ -1186,6 +1189,24 @@ static int msr_interception(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) return rdmsr_interception(vcpu, kvm_run); } +static int interrupt_window_interception(struct kvm_vcpu *vcpu, + struct kvm_run *kvm_run) +{ + /* + * If the user space waits to inject interrupts, exit as soon as + * possible + */ + if (kvm_run->request_interrupt_window && + !vcpu->irq_summary && + (vcpu->svm->vmcb->save.rflags & X86_EFLAGS_IF)) { + ++kvm_stat.irq_window_exits; + kvm_run->exit_reason = KVM_EXIT_IRQ_WINDOW_OPEN; + return 0; + } + + return 1; +} + static int (*svm_exit_handlers[])(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) = { [SVM_EXIT_READ_CR0] = emulate_on_interception, @@ -1210,6 +1231,7 @@ static int (*svm_exit_handlers[])(struct kvm_vcpu *vcpu, [SVM_EXIT_NMI] = nop_on_interception, [SVM_EXIT_SMI] = nop_on_interception, [SVM_EXIT_INIT] = nop_on_interception, + [SVM_EXIT_VINTR] = interrupt_window_interception, /* [SVM_EXIT_CR0_SEL_WRITE] = emulate_on_interception, */ [SVM_EXIT_CPUID] = cpuid_interception, [SVM_EXIT_HLT] = halt_interception, @@ -1278,15 +1300,11 @@ static void pre_svm_run(struct kvm_vcpu *vcpu) } -static inline void kvm_try_inject_irq(struct kvm_vcpu *vcpu) +static inline void kvm_do_inject_irq(struct kvm_vcpu *vcpu) { struct vmcb_control_area *control; - if (!vcpu->irq_summary) - return; - control = &vcpu->svm->vmcb->control; - control->int_vector = pop_irq(vcpu); control->int_ctl &= ~V_INTR_PRIO_MASK; control->int_ctl |= V_IRQ_MASK | @@ -1301,6 +1319,59 @@ static void kvm_reput_irq(struct kvm_vcpu *vcpu) control->int_ctl &= ~V_IRQ_MASK; push_irq(vcpu, control->int_vector); } + + vcpu->interrupt_window_open = + !(control->int_state & SVM_INTERRUPT_SHADOW_MASK); +} + +static void do_interrupt_requests(struct kvm_vcpu *vcpu, + struct kvm_run *kvm_run) +{ + struct vmcb_control_area *control = &vcpu->svm->vmcb->control; + + vcpu->interrupt_window_open = + (!(control->int_state & SVM_INTERRUPT_SHADOW_MASK) && + (vcpu->svm->vmcb->save.rflags & X86_EFLAGS_IF)); + + if (vcpu->interrupt_window_open && vcpu->irq_summary) + /* + * If interrupts enabled, and not blocked by sti or mov ss. Good. + */ + kvm_do_inject_irq(vcpu); + + /* + * Interrupts blocked. Wait for unblock. + */ + if (!vcpu->interrupt_window_open && + (vcpu->irq_summary || kvm_run->request_interrupt_window)) { + control->intercept |= 1ULL << INTERCEPT_VINTR; + } else + control->intercept &= ~(1ULL << INTERCEPT_VINTR); +} + +static void post_kvm_run_save(struct kvm_vcpu *vcpu, + struct kvm_run *kvm_run) +{ + kvm_run->ready_for_interrupt_injection = (vcpu->interrupt_window_open && + vcpu->irq_summary == 0); + kvm_run->if_flag = (vcpu->svm->vmcb->save.rflags & X86_EFLAGS_IF) != 0; + kvm_run->cr8 = vcpu->cr8; + kvm_run->apic_base = vcpu->apic_base; +} + +/* + * Check if userspace requested an interrupt window, and that the + * interrupt window is open. + * + * No need to exit to userspace if we already have an interrupt queued. + */ +static int dm_request_for_irq_injection(struct kvm_vcpu *vcpu, + struct kvm_run *kvm_run) +{ + return (!vcpu->irq_summary && + kvm_run->request_interrupt_window && + vcpu->interrupt_window_open && + (vcpu->svm->vmcb->save.rflags & X86_EFLAGS_IF)); } static void save_db_regs(unsigned long *db_regs) @@ -1326,7 +1397,7 @@ static int svm_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) u16 ldt_selector; again: - kvm_try_inject_irq(vcpu); + do_interrupt_requests(vcpu, kvm_run); clgi(); @@ -1487,17 +1558,26 @@ again: if (vcpu->svm->vmcb->control.exit_code == SVM_EXIT_ERR) { kvm_run->exit_type = KVM_EXIT_TYPE_FAIL_ENTRY; kvm_run->exit_reason = vcpu->svm->vmcb->control.exit_code; + post_kvm_run_save(vcpu, kvm_run); return 0; } if (handle_exit(vcpu, kvm_run)) { if (signal_pending(current)) { ++kvm_stat.signal_exits; + post_kvm_run_save(vcpu, kvm_run); + return -EINTR; + } + + if (dm_request_for_irq_injection(vcpu, kvm_run)) { + ++kvm_stat.request_irq_exits; + post_kvm_run_save(vcpu, kvm_run); return -EINTR; } kvm_resched(vcpu); goto again; } + post_kvm_run_save(vcpu, kvm_run); return 0; } |