RISC-V: KVM: Use ncsr_xyz() in kvm_riscv_vcpu_trap_redirect()

The H-extension CSRs accessed by kvm_riscv_vcpu_trap_redirect() will
trap when KVM RISC-V is running as Guest/VM hence remove these traps
by using ncsr_xyz() instead of csr_xyz().

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Tested-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Nutty Liu <liujingqi@lanxincomputing.com>
Link: https://lore.kernel.org/r/20250618113532.471448-8-apatel@ventanamicro.com
Signed-off-by: Anup Patel <anup@brainfault.org>

Author: avpatel

arch/riscv/kvm/vcpu_exit.c

@@ -9,6 +9,7 @@
 #include <linux/kvm_host.h>
 #include <asm/csr.h>
 #include <asm/insn-def.h>
+#include <asm/kvm_nacl.h>
 
 static int gstage_page_fault(struct kvm_vcpu *vcpu, struct kvm_run *run,
 			     struct kvm_cpu_trap *trap)
@@ -135,7 +136,7 @@ unsigned long kvm_riscv_vcpu_unpriv_read(struct kvm_vcpu *vcpu,
 void kvm_riscv_vcpu_trap_redirect(struct kvm_vcpu *vcpu,
 				  struct kvm_cpu_trap *trap)
 {
-	unsigned long vsstatus = csr_read(CSR_VSSTATUS);
+	unsigned long vsstatus = ncsr_read(CSR_VSSTATUS);
 
 	/* Change Guest SSTATUS.SPP bit */
 	vsstatus &= ~SR_SPP;
@@ -151,15 +152,15 @@ void kvm_riscv_vcpu_trap_redirect(struct kvm_vcpu *vcpu,
 	vsstatus &= ~SR_SIE;
 
 	/* Update Guest SSTATUS */
-	csr_write(CSR_VSSTATUS, vsstatus);
+	ncsr_write(CSR_VSSTATUS, vsstatus);
 
 	/* Update Guest SCAUSE, STVAL, and SEPC */
-	csr_write(CSR_VSCAUSE, trap->scause);
-	csr_write(CSR_VSTVAL, trap->stval);
-	csr_write(CSR_VSEPC, trap->sepc);
+	ncsr_write(CSR_VSCAUSE, trap->scause);
+	ncsr_write(CSR_VSTVAL, trap->stval);
+	ncsr_write(CSR_VSEPC, trap->sepc);
 
 	/* Set Guest PC to Guest exception vector */
-	vcpu->arch.guest_context.sepc = csr_read(CSR_VSTVEC);
+	vcpu->arch.guest_context.sepc = ncsr_read(CSR_VSTVEC);
 
 	/* Set Guest privilege mode to supervisor */
 	vcpu->arch.guest_context.sstatus |= SR_SPP;