[PATCH v2 07/20] KVM: arm64: Share more arm64 code with s390
From: Steffen Eiden
Date: Mon Aug 31 2026 - 13:21:20 EST
Mark functions that s390 can use to implement arm on s390 as shared
functions.
Signed-off-by: Steffen Eiden <seiden@xxxxxxxxxxxxx>
---
arch/arm64/kvm/arm.c | 3 +++
arch/arm64/kvm/guest.c | 11 +++++++----
arch/arm64/kvm/sys_regs.c | 36 ++++++++++++++++++++++++++++++++++++
3 files changed, 46 insertions(+), 4 deletions(-)
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 6b92a3c1d490..62e8b32ee74e 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -340,6 +340,7 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
kvm_arm_teardown_hypercalls(kvm);
}
+#ifdef ARM64_S390_COMMON
static bool kvm_has_full_ptr_auth(void)
{
bool apa, gpa, api, gpi, apa3, gpa3;
@@ -374,6 +375,8 @@ static bool kvm_has_full_ptr_auth(void)
(apa + api + apa3) == 1);
}
+#endif /* ARM64_S390_COMMON */
+
int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
{
int r;
diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c
index 6ca5a9f357cd..e978b2fbeb76 100644
--- a/arch/arm64/kvm/guest.c
+++ b/arch/arm64/kvm/guest.c
@@ -307,12 +307,12 @@ static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
return err;
}
-#endif /* ARM64_S390_COMMON */
-
#define vq_word(vq) (((vq) - SVE_VQ_MIN) / 64)
#define vq_mask(vq) ((u64)1 << ((vq) - SVE_VQ_MIN) % 64)
#define vq_present(vqs, vq) (!!((vqs)[vq_word(vq)] & vq_mask(vq)))
+#endif /* ARM64_S390_COMMON */
+
static int get_sve_vls(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
unsigned int max_vq, vq;
@@ -383,6 +383,7 @@ static int set_sve_vls(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
return 0;
}
+#ifdef ARM64_S390_COMMON
#define SVE_REG_SLICE_SHIFT 0
#define SVE_REG_SLICE_BITS 5
#define SVE_REG_ID_SHIFT (SVE_REG_SLICE_SHIFT + SVE_REG_SLICE_BITS)
@@ -399,6 +400,8 @@ static int set_sve_vls(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
#define KVM_SVE_ZREG_SIZE KVM_REG_SIZE(KVM_REG_ARM64_SVE_ZREG(0, 0))
#define KVM_SVE_PREG_SIZE KVM_REG_SIZE(KVM_REG_ARM64_SVE_PREG(0, 0))
+#endif /* ARM64_S390_COMMON */
+
/*
* Number of register slices required to cover each whole SVE register.
* NOTE: Only the first slice every exists, for now.
@@ -595,8 +598,6 @@ static unsigned long num_core_regs(const struct kvm_vcpu *vcpu)
return copy_core_reg_indices(vcpu, NULL);
}
-#endif /* ARM64_S390_COMMON */
-
static unsigned long num_sve_regs(const struct kvm_vcpu *vcpu)
{
const unsigned int slices = vcpu_sve_slices(vcpu);
@@ -658,6 +659,8 @@ static int copy_sve_reg_indices(const struct kvm_vcpu *vcpu,
return num_regs;
}
+#endif /* ARM64_S390_COMMON */
+
/**
* kvm_arm_num_regs - how many registers do we present via KVM_GET_ONE_REG
* @vcpu: the vCPU pointer
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 53d096803d9d..b167f9d06fd4 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -45,6 +45,7 @@
* 64bit interface.
*/
+#ifdef ARM64_S390_COMMON
static u64 sys_reg_to_index(const struct sys_reg_desc *reg);
static int set_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
u64 val);
@@ -82,6 +83,8 @@ static bool write_to_read_only(struct kvm_vcpu *vcpu,
"sys_reg write to read-only register");
}
+#endif /* ARM64_S390_COMMON */
+
enum sr_loc_attr {
SR_LOC_MEMORY = 0, /* Register definitely in memory */
SR_LOC_LOADED = BIT(0), /* Register on CPU, unless it cannot */
@@ -428,6 +431,7 @@ void vcpu_write_sys_reg(struct kvm_vcpu *vcpu, u64 val, enum vcpu_sysreg reg)
__vcpu_assign_sys_reg(vcpu, reg, val);
}
+#ifdef ARM64_S390_COMMON
/* CSSELR values; used to index KVM_REG_ARM_DEMUX_ID_CCSIDR */
#define CSSELR_MAX 14
@@ -533,6 +537,8 @@ static bool access_rw(struct kvm_vcpu *vcpu,
return true;
}
+#endif /* ARM64_S390_COMMON */
+
/*
* See note at ARMv7 ARM B1.14.4 (TL;DR: S/W ops are not easily virtualized).
*/
@@ -800,6 +806,7 @@ static bool access_gicv5_ppi_enabler(struct kvm_vcpu *vcpu,
return true;
}
+#ifdef ARM64_S390_COMMON
static bool trap_raz_wi(struct kvm_vcpu *vcpu,
struct sys_reg_params *p,
const struct sys_reg_desc *r)
@@ -853,6 +860,8 @@ static bool trap_oslsr_el1(struct kvm_vcpu *vcpu,
return true;
}
+#endif /* ARM64_S390_COMMON */
+
static int set_oslsr_el1(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
u64 val)
{
@@ -1011,6 +1020,7 @@ static u64 reset_actlr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
return actlr;
}
+#ifdef ARM64_S390_COMMON
static u64 reset_mpidr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
{
u64 mpidr = kvm_calculate_mpidr(vcpu);
@@ -1019,6 +1029,8 @@ static u64 reset_mpidr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
return mpidr;
}
+#endif /* ARM64_S390_COMMON */
+
static unsigned int hidden_visibility(const struct kvm_vcpu *vcpu,
const struct sys_reg_desc *r)
{
@@ -1922,6 +1934,7 @@ static u8 pmuver_to_perfmon(u8 pmuver)
}
}
+#ifdef ARM64_S390_COMMON
static u64 sanitise_id_aa64pfr0_el1(const struct kvm_vcpu *vcpu, u64 val);
static u64 sanitise_id_aa64pfr1_el1(const struct kvm_vcpu *vcpu, u64 val);
static u64 sanitise_id_aa64pfr2_el1(const struct kvm_vcpu *vcpu, u64 val);
@@ -2078,6 +2091,8 @@ static bool access_id_reg(struct kvm_vcpu *vcpu,
return true;
}
+#endif /* ARM64_S390_COMMON */
+
static unsigned int aa32_id_visibility(const struct kvm_vcpu *vcpu,
const struct sys_reg_desc *r)
{
@@ -2127,6 +2142,7 @@ static unsigned int fp8_visibility(const struct kvm_vcpu *vcpu,
return REG_HIDDEN;
}
+#ifdef ARM64_S390_COMMON
static u64 sanitise_id_aa64pfr0_el1(const struct kvm_vcpu *vcpu, u64 val)
{
if (!vcpu_has_sve(vcpu))
@@ -2288,6 +2304,8 @@ static int set_id_aa64dfr0_el1(struct kvm_vcpu *vcpu,
return set_id_reg(vcpu, rd, val);
}
+#endif /* ARM64_S390_COMMON */
+
static u64 read_sanitised_id_dfr0_el1(struct kvm_vcpu *vcpu,
const struct sys_reg_desc *rd)
{
@@ -2332,6 +2350,7 @@ static int set_id_dfr0_el1(struct kvm_vcpu *vcpu,
return set_id_reg(vcpu, rd, val);
}
+#ifdef ARM64_S390_COMMON
static int set_id_aa64pfr0_el1(struct kvm_vcpu *vcpu,
const struct sys_reg_desc *rd, u64 user_val)
{
@@ -2661,6 +2680,8 @@ static bool access_ccsidr(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
return true;
}
+#endif /* ARM64_S390_COMMON */
+
static int get_raz_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
u64 *val)
{
@@ -2764,6 +2785,7 @@ static bool bad_redir_trap(struct kvm_vcpu *vcpu,
SYS_REG_USER_FILTER(name, access_arch_timer, reset_val, 0, \
arch_timer_get_user, arch_timer_set_user, vis)
+#ifdef ARM64_S390_COMMON
/*
* Since reset() callback and field val are not used for idregs, they will be
* used for specific purposes for idregs.
@@ -2840,6 +2862,8 @@ static bool bad_redir_trap(struct kvm_vcpu *vcpu,
.val = 0, \
}
+#endif /* ARM64_S390_COMMON */
+
static bool access_sp_el1(struct kvm_vcpu *vcpu,
struct sys_reg_params *p,
const struct sys_reg_desc *r)
@@ -3212,6 +3236,7 @@ static void init_imp_id_regs(void)
boot_cpu_aidr_val = read_sysreg(aidr_el1);
}
+#ifdef ARM64_S390_COMMON
static u64 reset_imp_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
{
switch (reg_to_encoding(r)) {
@@ -3269,6 +3294,8 @@ static int set_imp_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r,
.val = mask, \
}
+#endif /* ARM64_S390_COMMON */
+
static u64 reset_mdcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
{
__vcpu_assign_sys_reg(vcpu, r->reg, vcpu->kvm->arch.nr_pmu_counters);
@@ -4833,6 +4860,7 @@ static const struct sys_reg_desc cp15_64_regs[] = {
{ SYS_DESC(SYS_AARCH32_CNTVCTSS), access_arch_timer },
};
+#ifdef ARM64_S390_COMMON
static bool check_sysreg_table(const struct sys_reg_desc *table, unsigned int n,
bool reset_check)
{
@@ -4882,6 +4910,8 @@ static void perform_access(struct kvm_vcpu *vcpu,
kvm_incr_pc(vcpu);
}
+#endif /* ARM64_S390_COMMON */
+
/*
* emulate_cp -- tries to match a sys_reg access in a handling table, and
* call the corresponding trap handler.
@@ -5340,6 +5370,7 @@ void kvm_sys_regs_create_debugfs(struct kvm *kvm)
&sr_resx_fops);
}
+#ifdef ARM64_S390_COMMON
static void reset_vm_ftr_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *reg)
{
u32 id = reg_to_encoding(reg);
@@ -5360,6 +5391,8 @@ static void reset_vcpu_ftr_id_reg(struct kvm_vcpu *vcpu,
reg->reset(vcpu, reg);
}
+#endif /* ARM64_S390_COMMON */
+
/**
* kvm_reset_sys_regs - sets system registers to reset value
* @vcpu: The VCPU pointer
@@ -5432,6 +5465,7 @@ int kvm_handle_sys_reg(struct kvm_vcpu *vcpu)
return 1;
}
+#ifdef ARM64_S390_COMMON
/******************************************************************************
* Userspace API
*****************************************************************************/
@@ -5753,6 +5787,8 @@ int kvm_arm_copy_sys_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
return write_demux_regids(uindices);
}
+#endif /* ARM64_S390_COMMON */
+
#define KVM_ARM_FEATURE_ID_RANGE_INDEX(r) \
KVM_ARM_FEATURE_ID_RANGE_IDX(sys_reg_Op0(r), \
sys_reg_Op1(r), \
--
2.53.0