KVM: arm64: Return a bool from emulate_cp()

KVM indicates success/failure in several ways, but generally an integer
is used when conditionally bouncing to userspace is involved. That is
not the case from emulate_cp(); just use a bool instead.

No functional change intended.
Signed-off-by: Oliver Upton <oupton@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220503060205.2823727-2-oupton@google.com

arch/arm64/kvm/sys_regs.c

@@ -2246,27 +2246,27 @@ static void perform_access(struct kvm_vcpu *vcpu,
  * @table: array of trap descriptors
  * @num: size of the trap descriptor array
  *
- * Return 0 if the access has been handled, and -1 if not.
+ * Return true if the access has been handled, false if not.
  */
-static int emulate_cp(struct kvm_vcpu *vcpu,
-		      struct sys_reg_params *params,
-		      const struct sys_reg_desc *table,
-		      size_t num)
+static bool emulate_cp(struct kvm_vcpu *vcpu,
+		       struct sys_reg_params *params,
+		       const struct sys_reg_desc *table,
+		       size_t num)
 {
 	const struct sys_reg_desc *r;
 
 	if (!table)
-		return -1;	/* Not handled */
+		return false;	/* Not handled */
 
 	r = find_reg(params, table, num);
 
 	if (r) {
 		perform_access(vcpu, params, r);
-		return 0;
+		return true;
 	}
 
 	/* Not handled */
-	return -1;
+	return false;
 }
 
 static void unhandled_cp_access(struct kvm_vcpu *vcpu,
@@ -2330,7 +2330,7 @@ static int kvm_handle_cp_64(struct kvm_vcpu *vcpu,
 	 * potential register operation in the case of a read and return
 	 * with success.
 	 */
-	if (!emulate_cp(vcpu, &params, global, nr_global)) {
+	if (emulate_cp(vcpu, &params, global, nr_global)) {
 		/* Split up the value between registers for the read side */
 		if (!params.is_write) {
 			vcpu_set_reg(vcpu, Rt, lower_32_bits(params.regval));
@@ -2365,7 +2365,7 @@ static int kvm_handle_cp_32(struct kvm_vcpu *vcpu,
 	params.Op1 = (esr >> 14) & 0x7;
 	params.Op2 = (esr >> 17) & 0x7;
 
-	if (!emulate_cp(vcpu, &params, global, nr_global)) {
+	if (emulate_cp(vcpu, &params, global, nr_global)) {
 		if (!params.is_write)
 			vcpu_set_reg(vcpu, Rt, params.regval);
 		return 1;