RISC-V: KVM: Use generic guest entry infrastructure

Use generic guest entry infrastructure to properly handle
TIF_NOTIFY_RESUME.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Anup Patel <anup@brainfault.org>

arch/riscv/kvm/Kconfig

@@ -24,6 +24,7 @@ config KVM
 	select PREEMPT_NOTIFIERS
 	select KVM_MMIO
 	select KVM_GENERIC_DIRTYLOG_READ_PROTECT
+	select KVM_XFER_TO_GUEST_WORK
 	select HAVE_KVM_VCPU_ASYNC_IOCTL
 	select HAVE_KVM_EVENTFD
 	select SRCU

arch/riscv/kvm/vcpu.c

@@ -7,6 +7,7 @@
  */
 
 #include <linux/bitops.h>
+#include <linux/entry-kvm.h>
 #include <linux/errno.h>
 #include <linux/err.h>
 #include <linux/kdebug.h>
@@ -979,7 +980,9 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
 	run->exit_reason = KVM_EXIT_UNKNOWN;
 	while (ret > 0) {
 		/* Check conditions before entering the guest */
-		cond_resched();
+		ret = xfer_to_guest_mode_handle_work(vcpu);
+		if (!ret)
+			ret = 1;
 
 		kvm_riscv_gstage_vmid_update(vcpu);
 
@@ -987,16 +990,6 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
 
 		local_irq_disable();
 
-		/*
-		 * Exit if we have a signal pending so that we can deliver
-		 * the signal to user space.
-		 */
-		if (signal_pending(current)) {
-			ret = -EINTR;
-			run->exit_reason = KVM_EXIT_INTR;
-			++vcpu->stat.signal_exits;
-		}
-
 		/*
 		 * Ensure we set mode to IN_GUEST_MODE after we disable
 		 * interrupts and before the final VCPU requests check.
@@ -1019,7 +1012,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
 
 		if (ret <= 0 ||
 		    kvm_riscv_gstage_vmid_ver_changed(&vcpu->kvm->arch.vmid) ||
-		    kvm_request_pending(vcpu)) {
+		    kvm_request_pending(vcpu) ||
+		    xfer_to_guest_mode_work_pending()) {
 			vcpu->mode = OUTSIDE_GUEST_MODE;
 			local_irq_enable();
 			kvm_vcpu_srcu_read_lock(vcpu);