[PATCH 10/13] KVM: arm64: Kill leftovers of ad-hoc timer userspace access

Marc Zyngier
2025-09-29T16:05:07Z

Now that the whole timer infrastructure is handled as system register
accesses, get rid of the now unused ad-hoc infrastructure.

Signed-off-by: Marc Zyngier <maz@kernel.org>
---
arch/arm64/kvm/arch_timer.c | 68 ------------------------------------
arch/arm64/kvm/guest.c | 55 -----------------------------
include/kvm/arm_arch_timer.h | 3 --
3 files changed, 126 deletions(-)

diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c
index 27662a3a3043e..3f675875abea2 100644
--- a/arch/arm64/kvm/arch_timer.c
+++ b/arch/arm64/kvm/arch_timer.c
@@ -1112,49 +1112,6 @@ void kvm_timer_cpu_down(void)
disable_percpu_irq(host_ptimer_irq);
}

-int kvm_arm_timer_set_reg(struct kvm_vcpu *vcpu, u64 regid, u64 value)
-{
- struct arch_timer_context *timer;
-
- switch (regid) {
- case KVM_REG_ARM_TIMER_CTL:
- timer = vcpu_vtimer(vcpu);
- kvm_arm_timer_write(vcpu, timer, TIMER_REG_CTL, value);
- break;
- case KVM_REG_ARM_TIMER_CNT:
- if (!test_bit(KVM_ARCH_FLAG_VM_COUNTER_OFFSET,
- &vcpu->kvm->arch.flags)) {
- timer = vcpu_vtimer(vcpu);
- timer_set_offset(timer, kvm_phys_timer_read() - value);
- }
- break;
- case KVM_REG_ARM_TIMER_CVAL:
- timer = vcpu_vtimer(vcpu);
- kvm_arm_timer_write(vcpu, timer, TIMER_REG_CVAL, value);
- break;
- case KVM_REG_ARM_PTIMER_CTL:
- timer = vcpu_ptimer(vcpu);
- kvm_arm_timer_write(vcpu, timer, TIMER_REG_CTL, value);
- break;
- case KVM_REG_ARM_PTIMER_CNT:
- if (!test_bit(KVM_ARCH_FLAG_VM_COUNTER_OFFSET,
- &vcpu->kvm->arch.flags)) {
- timer = vcpu_ptimer(vcpu);
- timer_set_offset(timer, kvm_phys_timer_read() - value);
- }
- break;
- case KVM_REG_ARM_PTIMER_CVAL:
- timer = vcpu_ptimer(vcpu);
- kvm_arm_timer_write(vcpu, timer, TIMER_REG_CVAL, value);
- break;
-
- default:
- return -1;
- }
-
- return 0;
-}
-
static u64 read_timer_ctl(struct arch_timer_context *timer)
{
/*
@@ -1171,31 +1128,6 @@ static u64 read_timer_ctl(struct arch_timer_context *timer)
return ctl;
}

-u64 kvm_arm_timer_get_reg(struct kvm_vcpu *vcpu, u64 regid)
-{
- switch (regid) {
- case KVM_REG_ARM_TIMER_CTL:
- return kvm_arm_timer_read(vcpu,
- vcpu_vtimer(vcpu), TIMER_REG_CTL);
- case KVM_REG_ARM_TIMER_CNT:
- return kvm_arm_timer_read(vcpu,
- vcpu_vtimer(vcpu), TIMER_REG_CNT);
- case KVM_REG_ARM_TIMER_CVAL:
- return kvm_arm_timer_read(vcpu,
- vcpu_vtimer(vcpu), TIMER_REG_CVAL);
- case KVM_REG_ARM_PTIMER_CTL:
- return kvm_arm_timer_read(vcpu,
- vcpu_ptimer(vcpu), TIMER_REG_CTL);
- case KVM_REG_ARM_PTIMER_CNT:
- return kvm_arm_timer_read(vcpu,
- vcpu_ptimer(vcpu), TIMER_REG_CNT);
- case KVM_REG_ARM_PTIMER_CVAL:
- return kvm_arm_timer_read(vcpu,
- vcpu_ptimer(vcpu), TIMER_REG_CVAL);
- }
- return (u64)-1;
-}
-
static u64 kvm_arm_timer_read(struct kvm_vcpu *vcpu,
struct arch_timer_context *timer,
enum kvm_arch_timer_regs treg)
diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c
index 138e5e2dc10c8..1c87699fd886e 100644
--- a/arch/arm64/kvm/guest.c
+++ b/arch/arm64/kvm/guest.c
@@ -591,49 +591,6 @@ static unsigned long num_core_regs(const struct kvm_vcpu *vcpu)
return copy_core_reg_indices(vcpu, NULL);
}

-static const u64 timer_reg_list[] = {
-};
-
-#define NUM_TIMER_REGS ARRAY_SIZE(timer_reg_list)
-
-static bool is_timer_reg(u64 index)
-{
- return false;
-}
-
-static int copy_timer_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
-{
- for (int i = 0; i < NUM_TIMER_REGS; i++) {
- if (put_user(timer_reg_list[i], uindices))
- return -EFAULT;
- uindices++;
- }
-
- return 0;
-}
-
-static int set_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
-{
- void __user *uaddr = (void __user *)(long)reg->addr;
- u64 val;
- int ret;
-
- ret = copy_from_user(&val, uaddr, KVM_REG_SIZE(reg->id));
- if (ret != 0)
- return -EFAULT;
-
- return kvm_arm_timer_set_reg(vcpu, reg->id, val);
-}
-
-static int get_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
-{
- void __user *uaddr = (void __user *)(long)reg->addr;
- u64 val;
-
- val = kvm_arm_timer_get_reg(vcpu, reg->id);
- return copy_to_user(uaddr, &val, KVM_REG_SIZE(reg->id)) ? -EFAULT : 0;
-}
-
static unsigned long num_sve_regs(const struct kvm_vcpu *vcpu)
{
const unsigned int slices = vcpu_sve_slices(vcpu);
@@ -709,7 +666,6 @@ unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu)
res += num_sve_regs(vcpu);
res += kvm_arm_num_sys_reg_descs(vcpu);
res += kvm_arm_get_fw_num_regs(vcpu);
- res += NUM_TIMER_REGS;

return res;
}
@@ -740,11 +696,6 @@ int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
return ret;
uindices += kvm_arm_get_fw_num_regs(vcpu);

- ret = copy_timer_indices(vcpu, uindices);
- if (ret < 0)
- return ret;
- uindices += NUM_TIMER_REGS;
-
return kvm_arm_copy_sys_reg_indices(vcpu, uindices);
}

@@ -762,9 +713,6 @@ int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
case KVM_REG_ARM64_SVE: return get_sve_reg(vcpu, reg);
}

- if (is_timer_reg(reg->id))
- return get_timer_reg(vcpu, reg);
-
return kvm_arm_sys_reg_get_reg(vcpu, reg);
}

@@ -782,9 +730,6 @@ int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
case KVM_REG_ARM64_SVE: return set_sve_reg(vcpu, reg);
}

- if (is_timer_reg(reg->id))
- return set_timer_reg(vcpu, reg);
-
return kvm_arm_sys_reg_set_reg(vcpu, reg);
}

diff --git a/include/kvm/arm_arch_timer.h b/include/kvm/arm_arch_timer.h
index 5f7f2ed8817c5..7310841f45121 100644
--- a/include/kvm/arm_arch_timer.h
+++ b/include/kvm/arm_arch_timer.h
@@ -107,9 +107,6 @@ void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu);

void kvm_timer_init_vm(struct kvm *kvm);

-u64 kvm_arm_timer_get_reg(struct kvm_vcpu *, u64 regid);
-int kvm_arm_timer_set_reg(struct kvm_vcpu *, u64 regid, u64 value);
-
int kvm_arm_timer_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr);
int kvm_arm_timer_get_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr);
int kvm_arm_timer_has_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr);
--
2.47.3