On Tue, Aug 27, 2013 at 04:08:01PM +0200, Andre Przywara wrote: > For migration to work we need to save (and later restore) the state of > each cores virtual generic timer. > Since this is per VCPU, we can use the [gs]et_one_reg ioctl and export > the three needed registers (control, counter, compare value). > Though they live in cp15 space, we don't use the existing list, since > they need special accessor functions and the arch timer is optional. > > Changes from v1: > - move code out of coproc.c and into guest.c and arch_timer.c > - present the registers with their native CP15 addresses, but without > using space in the VCPU's cp15 array > - do the user space copying in the accessor functions > > Changes from v2: > - fix compilation without CONFIG_ARCH_TIMER > - fix compilation for arm64 by defining the appropriate registers there > - move userspace access out of arch_timer.c into coproc.c > > Signed-off-by: Andre Przywara <andre.przywara@xxxxxxxxxx> This looks good to me. Reviewed-by: Christoffer Dall <christoffer.dall@xxxxxxxxxx> > --- > arch/arm/include/asm/kvm_host.h | 3 ++ > arch/arm/include/uapi/asm/kvm.h | 16 +++++++ > arch/arm/kvm/guest.c | 92 ++++++++++++++++++++++++++++++++++++++- > arch/arm64/include/uapi/asm/kvm.h | 25 +++++++++++ > virt/kvm/arm/arch_timer.c | 34 +++++++++++++++ > 5 files changed, 169 insertions(+), 1 deletion(-) > > diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h > index 7d22517..b02753d 100644 > --- a/arch/arm/include/asm/kvm_host.h > +++ b/arch/arm/include/asm/kvm_host.h > @@ -229,4 +229,7 @@ static inline int kvm_arch_dev_ioctl_check_extension(long ext) > int kvm_perf_init(void); > int kvm_perf_teardown(void); > > +u64 kvm_arm_timer_get_reg(struct kvm_vcpu *, u64 regid); > +int kvm_arm_timer_set_reg(struct kvm_vcpu *, u64 regid, u64 value); > + > #endif /* __ARM_KVM_HOST_H__ */ > diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h > index c1ee007..e3b0115 100644 > --- a/arch/arm/include/uapi/asm/kvm.h > +++ b/arch/arm/include/uapi/asm/kvm.h > @@ -118,6 +118,22 @@ struct kvm_arch_memory_slot { > #define KVM_REG_ARM_32_CRN_MASK 0x0000000000007800 > #define KVM_REG_ARM_32_CRN_SHIFT 11 > > +#define KVM_REG_ARM_32_CP15 (KVM_REG_ARM | KVM_REG_SIZE_U32 | \ > + (15ULL << KVM_REG_ARM_COPROC_SHIFT)) > +#define KVM_REG_ARM_64_CP15 (KVM_REG_ARM | KVM_REG_SIZE_U64 | \ > + (15ULL << KVM_REG_ARM_COPROC_SHIFT)) > +#define KVM_REG_ARM_TIMER_CTL (KVM_REG_ARM_32_CP15 | \ > + ( 3ULL << KVM_REG_ARM_CRM_SHIFT) | \ > + (14ULL << KVM_REG_ARM_32_CRN_SHIFT) | \ > + ( 0ULL << KVM_REG_ARM_OPC1_SHIFT) | \ > + ( 1ULL << KVM_REG_ARM_32_OPC2_SHIFT)) > +#define KVM_REG_ARM_TIMER_CNT (KVM_REG_ARM_64_CP15 | \ > + (14ULL << KVM_REG_ARM_CRM_SHIFT) | \ > + ( 1ULL << KVM_REG_ARM_OPC1_SHIFT)) > +#define KVM_REG_ARM_TIMER_CVAL (KVM_REG_ARM_64_CP15 | \ > + (14ULL << KVM_REG_ARM_CRM_SHIFT) | \ > + ( 3ULL << KVM_REG_ARM_OPC1_SHIFT)) > + > /* Normal registers are mapped as coprocessor 16. */ > #define KVM_REG_ARM_CORE (0x0010 << KVM_REG_ARM_COPROC_SHIFT) > #define KVM_REG_ARM_CORE_REG(name) (offsetof(struct kvm_regs, name) / 4) > diff --git a/arch/arm/kvm/guest.c b/arch/arm/kvm/guest.c > index 152d036..c028d1e 100644 > --- a/arch/arm/kvm/guest.c > +++ b/arch/arm/kvm/guest.c > @@ -109,6 +109,83 @@ int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs) > return -EINVAL; > } > > +#ifndef CONFIG_KVM_ARM_TIMER > + > +#define NUM_TIMER_REGS 0 > + > +static int copy_timer_indices (struct kvm_vcpu *vcpu, u64 __user *uindices) stray whitespace, can be fixed on commit if we don't respin > +{ > + return 0; > +} > + > +static bool is_timer_reg(u64 index) > +{ > + return false; > +} > + > +int kvm_arm_timer_set_reg(struct kvm_vcpu *vcpu, u64 regid, u64 value) > +{ > + return 0; > +} > + > +u64 kvm_arm_timer_get_reg(struct kvm_vcpu *vcpu, u64 regid) > +{ > + return 0; > +} > + > +#else > + > +#define NUM_TIMER_REGS 3 > + > +static bool is_timer_reg(u64 index) > +{ > + switch (index) { > + case KVM_REG_ARM_TIMER_CTL: > + case KVM_REG_ARM_TIMER_CNT: > + case KVM_REG_ARM_TIMER_CVAL: > + return true; > + } > + return false; > +} > + > +static int copy_timer_indices(struct kvm_vcpu *vcpu, u64 __user *uindices) > +{ > + if (put_user(KVM_REG_ARM_TIMER_CTL, uindices)) > + return -EFAULT; > + uindices++; > + if (put_user(KVM_REG_ARM_TIMER_CNT, uindices)) > + return -EFAULT; > + uindices++; > + if (put_user(KVM_REG_ARM_TIMER_CVAL, uindices)) > + return -EFAULT; > + > + return 0; > +} > + > +#endif > + > +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 ret; > + > + 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)); > +} > + > static unsigned long num_core_regs(void) > { > return sizeof(struct kvm_regs) / sizeof(u32); > @@ -121,7 +198,8 @@ static unsigned long num_core_regs(void) > */ > unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu) > { > - return num_core_regs() + kvm_arm_num_coproc_regs(vcpu); > + return num_core_regs() + kvm_arm_num_coproc_regs(vcpu) > + + NUM_TIMER_REGS; > } > > /** > @@ -133,6 +211,7 @@ int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices) > { > unsigned int i; > const u64 core_reg = KVM_REG_ARM | KVM_REG_SIZE_U32 | KVM_REG_ARM_CORE; > + int ret; > > for (i = 0; i < sizeof(struct kvm_regs)/sizeof(u32); i++) { > if (put_user(core_reg | i, uindices)) > @@ -140,6 +219,11 @@ int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices) > uindices++; > } > > + ret = copy_timer_indices(vcpu, uindices); > + if (ret) > + return ret; > + uindices += NUM_TIMER_REGS; > + > return kvm_arm_copy_coproc_indices(vcpu, uindices); > } > > @@ -153,6 +237,9 @@ int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) > if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE) > return get_core_reg(vcpu, reg); > > + if (is_timer_reg(reg->id)) > + return get_timer_reg(vcpu, reg); > + > return kvm_arm_coproc_get_reg(vcpu, reg); > } > > @@ -166,6 +253,9 @@ int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) > if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE) > return set_core_reg(vcpu, reg); > > + if (is_timer_reg(reg->id)) > + return set_timer_reg(vcpu, reg); > + > return kvm_arm_coproc_set_reg(vcpu, reg); > } > > diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h > index 5031f42..9e2ab9e 100644 > --- a/arch/arm64/include/uapi/asm/kvm.h > +++ b/arch/arm64/include/uapi/asm/kvm.h > @@ -129,6 +129,31 @@ struct kvm_arch_memory_slot { > #define KVM_REG_ARM64_SYSREG_OP2_MASK 0x0000000000000007 > #define KVM_REG_ARM64_SYSREG_OP2_SHIFT 0 > > +#define KVM_REG_ARM64_32_SYSREG (KVM_REG_ARM64 | KVM_REG_SIZE_U32 | \ > + KVM_REG_ARM64_SYSREG) > +#define KVM_REG_ARM64_64_SYSREG (KVM_REG_ARM64 | KVM_REG_SIZE_U64 | \ > + KVM_REG_ARM64_SYSREG) > +#define KVM_REG_ARM_TIMER_CTL (KVM_REG_ARM64_32_SYSREG | \ > + ( 3ULL << KVM_REG_ARM64_SYSREG_OP0_SHIFT) | \ > + ( 3ULL << KVM_REG_ARM64_SYSREG_OP1_SHIFT) | \ > + (14ULL << KVM_REG_ARM64_SYSREG_CRN_SHIFT) | \ > + ( 3ULL << KVM_REG_ARM64_SYSREG_CRM_SHIFT) | \ > + ( 1ULL << KVM_REG_ARM64_SYSREG_OP2_SHIFT)) > + > +#define KVM_REG_ARM_TIMER_CNT (KVM_REG_ARM64_64_SYSREG | \ > + ( 3ULL << KVM_REG_ARM64_SYSREG_OP0_SHIFT) | \ > + ( 3ULL << KVM_REG_ARM64_SYSREG_OP1_SHIFT) | \ > + (14ULL << KVM_REG_ARM64_SYSREG_CRN_SHIFT) | \ > + ( 3ULL << KVM_REG_ARM64_SYSREG_CRM_SHIFT) | \ > + ( 2ULL << KVM_REG_ARM64_SYSREG_OP2_SHIFT)) > + > +#define KVM_REG_ARM_TIMER_CVAL (KVM_REG_ARM64_64_SYSREG | \ > + ( 3ULL << KVM_REG_ARM64_SYSREG_OP0_SHIFT) | \ > + ( 3ULL << KVM_REG_ARM64_SYSREG_OP1_SHIFT) | \ > + (14ULL << KVM_REG_ARM64_SYSREG_CRN_SHIFT) | \ > + ( 0ULL << KVM_REG_ARM64_SYSREG_CRM_SHIFT) | \ > + ( 2ULL << KVM_REG_ARM64_SYSREG_OP2_SHIFT)) > + > /* KVM_IRQ_LINE irq field index values */ > #define KVM_ARM_IRQ_TYPE_SHIFT 24 > #define KVM_ARM_IRQ_TYPE_MASK 0xff > diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c > index c2e1ef4..5081e80 100644 > --- a/virt/kvm/arm/arch_timer.c > +++ b/virt/kvm/arm/arch_timer.c > @@ -182,6 +182,40 @@ static void kvm_timer_init_interrupt(void *info) > enable_percpu_irq(host_vtimer_irq, 0); > } > > +int kvm_arm_timer_set_reg(struct kvm_vcpu *vcpu, u64 regid, u64 value) > +{ > + struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; > + > + switch (regid) { > + case KVM_REG_ARM_TIMER_CTL: > + timer->cntv_ctl = value; > + break; > + case KVM_REG_ARM_TIMER_CNT: > + vcpu->kvm->arch.timer.cntvoff = kvm_phys_timer_read() - value; > + break; > + case KVM_REG_ARM_TIMER_CVAL: > + timer->cntv_cval = value; > + break; > + default: > + return -1; > + } > + return 0; > +} > + > +u64 kvm_arm_timer_get_reg(struct kvm_vcpu *vcpu, u64 regid) > +{ > + struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; > + > + switch (regid) { > + case KVM_REG_ARM_TIMER_CTL: > + return timer->cntv_ctl; > + case KVM_REG_ARM_TIMER_CNT: > + return kvm_phys_timer_read() - vcpu->kvm->arch.timer.cntvoff; > + case KVM_REG_ARM_TIMER_CVAL: > + return timer->cntv_cval; > + } > + return (u64)-1; > +} > > static int kvm_timer_cpu_notify(struct notifier_block *self, > unsigned long action, void *cpu) > -- > 1.7.12.1 > _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/cucslists/listinfo/kvmarm