RISC-V: KVM: Move copy_sbi_ext_reg_indices() to SBI implementation

The ONE_REG handling of SBI extension enable/disable registers and
SBI extension state registers is already under SBI implementation.
On similar lines, let's move copy_sbi_ext_reg_indices() under SBI
implementation.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20250823155947.1354229-5-apatel@ventanamicro.com
Signed-off-by: Anup Patel <anup@brainfault.org>

Author: avpatel

arch/riscv/include/asm/kvm_vcpu_sbi.h

@@ -77,6 +77,7 @@ void kvm_riscv_vcpu_sbi_request_reset(struct kvm_vcpu *vcpu,
 				      unsigned long pc, unsigned long a1);
 void kvm_riscv_vcpu_sbi_load_reset_state(struct kvm_vcpu *vcpu);
 int kvm_riscv_vcpu_sbi_return(struct kvm_vcpu *vcpu, struct kvm_run *run);
+int kvm_riscv_vcpu_reg_indices_sbi_ext(struct kvm_vcpu *vcpu, u64 __user *uindices);
 int kvm_riscv_vcpu_set_reg_sbi_ext(struct kvm_vcpu *vcpu,
 				   const struct kvm_one_reg *reg);
 int kvm_riscv_vcpu_get_reg_sbi_ext(struct kvm_vcpu *vcpu,
@@ -86,7 +87,6 @@ int kvm_riscv_vcpu_set_reg_sbi(struct kvm_vcpu *vcpu, const struct kvm_one_reg *
 int kvm_riscv_vcpu_get_reg_sbi(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
 const struct kvm_vcpu_sbi_extension *kvm_vcpu_sbi_find_ext(
 				struct kvm_vcpu *vcpu, unsigned long extid);
-bool riscv_vcpu_supports_sbi_ext(struct kvm_vcpu *vcpu, int idx);
 int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run);
 void kvm_riscv_vcpu_sbi_init(struct kvm_vcpu *vcpu);
 void kvm_riscv_vcpu_sbi_deinit(struct kvm_vcpu *vcpu);

arch/riscv/kvm/vcpu_onereg.c

@@ -1082,34 +1082,9 @@ static inline unsigned long num_isa_ext_regs(const struct kvm_vcpu *vcpu)
 	return copy_isa_ext_reg_indices(vcpu, NULL);
 }
 
-static int copy_sbi_ext_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
-{
-	unsigned int n = 0;
-
-	for (int i = 0; i < KVM_RISCV_SBI_EXT_MAX; i++) {
-		u64 size = IS_ENABLED(CONFIG_32BIT) ?
-			   KVM_REG_SIZE_U32 : KVM_REG_SIZE_U64;
-		u64 reg = KVM_REG_RISCV | size | KVM_REG_RISCV_SBI_EXT |
-			  KVM_REG_RISCV_SBI_SINGLE | i;
-
-		if (!riscv_vcpu_supports_sbi_ext(vcpu, i))
-			continue;
-
-		if (uindices) {
-			if (put_user(reg, uindices))
-				return -EFAULT;
-			uindices++;
-		}
-
-		n++;
-	}
-
-	return n;
-}
-
 static unsigned long num_sbi_ext_regs(struct kvm_vcpu *vcpu)
 {
-	return copy_sbi_ext_reg_indices(vcpu, NULL);
+	return kvm_riscv_vcpu_reg_indices_sbi_ext(vcpu, NULL);
 }
 
 static inline unsigned long num_sbi_regs(struct kvm_vcpu *vcpu)
@@ -1237,7 +1212,7 @@ int kvm_riscv_vcpu_copy_reg_indices(struct kvm_vcpu *vcpu,
 		return ret;
 	uindices += ret;
 
-	ret = copy_sbi_ext_reg_indices(vcpu, uindices);
+	ret = kvm_riscv_vcpu_reg_indices_sbi_ext(vcpu, uindices);
 	if (ret < 0)
 		return ret;
 	uindices += ret;

arch/riscv/kvm/vcpu_sbi.c

@@ -110,7 +110,7 @@ riscv_vcpu_get_sbi_ext(struct kvm_vcpu *vcpu, unsigned long idx)
 	return sext;
 }
 
-bool riscv_vcpu_supports_sbi_ext(struct kvm_vcpu *vcpu, int idx)
+static bool riscv_vcpu_supports_sbi_ext(struct kvm_vcpu *vcpu, int idx)
 {
 	struct kvm_vcpu_sbi_context *scontext = &vcpu->arch.sbi_context;
 	const struct kvm_riscv_sbi_extension_entry *sext;
@@ -288,6 +288,31 @@ static int riscv_vcpu_get_sbi_ext_multi(struct kvm_vcpu *vcpu,
 	return 0;
 }
 
+int kvm_riscv_vcpu_reg_indices_sbi_ext(struct kvm_vcpu *vcpu, u64 __user *uindices)
+{
+	unsigned int n = 0;
+
+	for (int i = 0; i < KVM_RISCV_SBI_EXT_MAX; i++) {
+		u64 size = IS_ENABLED(CONFIG_32BIT) ?
+			   KVM_REG_SIZE_U32 : KVM_REG_SIZE_U64;
+		u64 reg = KVM_REG_RISCV | size | KVM_REG_RISCV_SBI_EXT |
+			  KVM_REG_RISCV_SBI_SINGLE | i;
+
+		if (!riscv_vcpu_supports_sbi_ext(vcpu, i))
+			continue;
+
+		if (uindices) {
+			if (put_user(reg, uindices))
+				return -EFAULT;
+			uindices++;
+		}
+
+		n++;
+	}
+
+	return n;
+}
+
 int kvm_riscv_vcpu_set_reg_sbi_ext(struct kvm_vcpu *vcpu,
 				   const struct kvm_one_reg *reg)
 {