[PATCH v7 07/30] LoongArch: KVM: Implement vcpu run interface

From: Tianrui Zhao
Date: Mon Apr 17 2023 - 05:48:19 EST


Implement vcpu run interface, handling mmio, iocsr reading fault
and deliver interrupt, lose fpu before vcpu enter guest.

Signed-off-by: Tianrui Zhao <zhaotianrui@xxxxxxxxxxx>
---
arch/loongarch/kvm/vcpu.c | 86 +++++++++++++++++++++++++++++++++++++++
1 file changed, 86 insertions(+)

diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c
index 7af2ff64b8c7..bc9e3889fee1 100644
--- a/arch/loongarch/kvm/vcpu.c
+++ b/arch/loongarch/kvm/vcpu.c
@@ -18,6 +18,44 @@ int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
return 0;
}

+/* Returns 1 if the guest TLB may be clobbered */
+static int _kvm_check_requests(struct kvm_vcpu *vcpu, int cpu)
+{
+ int ret = 0;
+
+ if (!kvm_request_pending(vcpu))
+ return 0;
+
+ if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu)) {
+ /* Drop vpid for this VCPU */
+ vcpu->arch.vpid = 0;
+ /* This will clobber guest TLB contents too */
+ ret = 1;
+ }
+
+ return ret;
+}
+
+static void kvm_pre_enter_guest(struct kvm_vcpu *vcpu)
+{
+ int cpu;
+
+ /*
+ * handle vcpu timer, interrupts, check requests and
+ * check vmid before vcpu enter guest
+ */
+ kvm_acquire_timer(vcpu);
+ _kvm_deliver_intr(vcpu);
+ /* make sure the vcpu mode has been written */
+ smp_store_mb(vcpu->mode, IN_GUEST_MODE);
+ cpu = smp_processor_id();
+ _kvm_check_requests(vcpu, cpu);
+ _kvm_check_vmid(vcpu, cpu);
+ vcpu->arch.host_eentry = csr_read64(LOONGARCH_CSR_EENTRY);
+ /* clear KVM_LARCH_CSR as csr will change when enter guest */
+ vcpu->arch.aux_inuse &= ~KVM_LARCH_CSR;
+}
+
int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
{
unsigned long timer_hz;
@@ -87,3 +125,51 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
context->last_vcpu = NULL;
}
}
+
+int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
+{
+ int r = -EINTR;
+ struct kvm_run *run = vcpu->run;
+
+ vcpu_load(vcpu);
+
+ kvm_sigset_activate(vcpu);
+
+ if (vcpu->mmio_needed) {
+ if (!vcpu->mmio_is_write)
+ _kvm_complete_mmio_read(vcpu, run);
+ vcpu->mmio_needed = 0;
+ }
+
+ if (run->exit_reason == KVM_EXIT_LOONGARCH_IOCSR) {
+ if (!run->iocsr_io.is_write)
+ _kvm_complete_iocsr_read(vcpu, run);
+ }
+
+ /* clear exit_reason */
+ run->exit_reason = KVM_EXIT_UNKNOWN;
+ if (run->immediate_exit)
+ goto out;
+
+ lose_fpu(1);
+
+ local_irq_disable();
+ guest_timing_enter_irqoff();
+
+ kvm_pre_enter_guest(vcpu);
+ trace_kvm_enter(vcpu);
+
+ guest_state_enter_irqoff();
+ r = kvm_loongarch_ops->enter_guest(run, vcpu);
+
+ /* guest_state_exit_irqoff() already done. */
+ trace_kvm_out(vcpu);
+ guest_timing_exit_irqoff();
+ local_irq_enable();
+
+out:
+ kvm_sigset_deactivate(vcpu);
+
+ vcpu_put(vcpu);
+ return r;
+}
--
2.31.1