static int __vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
{
int r;
again:
preempt_disable();
kvm_prepare_guest_switch(vcpu);
local_irq_disable();
if (signal_pending(current)) {
local_irq_enable();
preempt_enable();
r = -EINTR;
kvm_run->exit_reason = KVM_EXIT_INTR;
goto out;
}
vcpu->guest_mode = 1;
kvm_guest_enter();
r = vti_vcpu_run(vcpu, kvm_run);
if (r < 0) {
local_irq_enable();
preempt_enable();
kvm_run->exit_reason = KVM_EXIT_FAIL_ENTRY;
goto out;
}
vcpu->arch.launched = 1;
vcpu->guest_mode = 0;
local_irq_enable();
/*
* We must have an instruction between local_irq_enable() and
* kvm_guest_exit(), so the timer interrupt isn't delayed by
* the interrupt shadow. The stat.exits increment will do nicely.
* But we need to prevent reordering, hence this barrier():
*/
barrier();
kvm_guest_exit();
preempt_enable();
r = kvm_handle_exit(kvm_run, vcpu);
if (r > 0) {
if (!need_resched())
goto again;
}
out:
if (r > 0) {
kvm_resched(vcpu);
goto again;
}
return r;
}
int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
int r;
sigset_t sigsaved;
vcpu_load(vcpu);
if (vcpu->sigset_active)
sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
if (vcpu->mmio_needed) {
if (!vcpu->mmio_is_write)
kvmppc_complete_mmio_load(vcpu, run);
vcpu->mmio_needed = 0;
} else if (vcpu->arch.dcr_needed) {
if (!vcpu->arch.dcr_is_write)
kvmppc_complete_dcr_load(vcpu, run);
vcpu->arch.dcr_needed = 0;
}
kvmppc_core_deliver_interrupts(vcpu);
local_irq_disable();
kvm_guest_enter();
r = __kvmppc_vcpu_run(run, vcpu);
kvm_guest_exit();
local_irq_enable();
if (vcpu->sigset_active)
sigprocmask(SIG_SETMASK, &sigsaved, NULL);
vcpu_put(vcpu);
return r;
}
int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
{
int ret;
if (!vcpu->arch.sane) {
kvm_run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
return -EINVAL;
}
local_irq_disable();
kvmppc_core_prepare_to_enter(vcpu);
if (signal_pending(current)) {
kvm_run->exit_reason = KVM_EXIT_INTR;
ret = -EINTR;
goto out;
}
kvm_guest_enter();
ret = __kvmppc_vcpu_run(kvm_run, vcpu);
kvm_guest_exit();
out:
local_irq_enable();
return ret;
}
int kvmppc_vcpu_run(struct kvm_run *run, struct kvm_vcpu *vcpu)
{
u64 now;
if (signal_pending(current)) {
run->exit_reason = KVM_EXIT_INTR;
return -EINTR;
}
flush_fp_to_thread(current);
flush_altivec_to_thread(current);
flush_vsx_to_thread(current);
preempt_disable();
/*
* Make sure we are running on thread 0, and that
* secondary threads are offline.
* XXX we should also block attempts to bring any
* secondary threads online.
*/
if (threads_per_core > 1) {
int cpu = smp_processor_id();
int thr = cpu_thread_in_core(cpu);
if (thr)
goto out;
while (++thr < threads_per_core)
if (cpu_online(cpu + thr))
goto out;
}
kvm_guest_enter();
__kvmppc_vcore_entry(NULL, vcpu);
kvm_guest_exit();
preempt_enable();
kvm_resched(vcpu);
now = get_tb();
/* cancel pending dec exception if dec is positive */
if (now < vcpu->arch.dec_expires && kvmppc_core_pending_dec(vcpu))
kvmppc_core_dequeue_dec(vcpu);
return kvmppc_handle_exit(run, vcpu, current);
out:
preempt_enable();
return -EBUSY;
}
/*
* Common checks before entering the guest world. Call with interrupts
* disabled.
*
* returns:
*
* == 1 if we're ready to go into guest state
* <= 0 if we need to go back to the host with return value
*/
int kvmppc_prepare_to_enter(struct kvm_vcpu *vcpu)
{
int r = 1;
WARN_ON_ONCE(!irqs_disabled());
while (true) {
if (need_resched()) {
local_irq_enable();
cond_resched();
local_irq_disable();
continue;
}
if (signal_pending(current)) {
kvmppc_account_exit(vcpu, SIGNAL_EXITS);
vcpu->run->exit_reason = KVM_EXIT_INTR;
r = -EINTR;
break;
}
vcpu->mode = IN_GUEST_MODE;
/*
* Reading vcpu->requests must happen after setting vcpu->mode,
* so we don't miss a request because the requester sees
* OUTSIDE_GUEST_MODE and assumes we'll be checking requests
* before next entering the guest (and thus doesn't IPI).
*/
smp_mb();
if (vcpu->requests) {
/* Make sure we process requests preemptable */
local_irq_enable();
trace_kvm_check_requests(vcpu);
r = kvmppc_core_check_requests(vcpu);
local_irq_disable();
if (r > 0)
continue;
break;
}
if (kvmppc_core_prepare_to_enter(vcpu)) {
/* interrupts got enabled in between, so we
are back at square 1 */
continue;
}
#ifdef CONFIG_PPC64
/* lazy EE magic */
hard_irq_disable();
if (lazy_irq_pending()) {
/* Got an interrupt in between, try again */
local_irq_enable();
local_irq_disable();
kvm_guest_exit();
continue;
}
#endif
kvm_guest_enter();
break;
}
return r;
}
