Re: [PATCH RFC v4 4/9] target/loongarch: Implement kvm get/set registers

[Philippe Mathieu-Daudé]

Hi Li and Zhao,

On 9/10/23 11:01, xianglai li wrote:
> From: Tianrui Zhao <zhaotianrui@loongson.cn>
>
> Implement kvm_arch_get/set_registers interfaces, many regs
> can be get/set in the function, such as core regs, csr regs,
> fpu regs, mp state, etc.
>
> Cc: "Michael S. Tsirkin" <mst@redhat.com>
> Cc: Cornelia Huck <cohuck@redhat.com>
> Cc: Paolo Bonzini <pbonzini@redhat.com>
> Cc: "Marc-André Lureau" <marcandre.lureau@redhat.com>
> Cc: "Daniel P. Berrangé" <berrange@redhat.com>
> Cc: Thomas Huth <thuth@redhat.com>
> Cc: "Philippe Mathieu-Daudé" <philmd@linaro.org>
> Cc: Richard Henderson <richard.henderson@linaro.org>
> Cc: Peter Maydell <peter.maydell@linaro.org>
> Cc: Bibo Mao <maobibo@loongson.cn>
> Cc: Song Gao <gaosong@loongson.cn>
> Cc: Xiaojuan Yang <yangxiaojuan@loongson.cn>
> Cc: Tianrui Zhao <zhaotianrui@loongson.cn>
>
> Signed-off-by: Tianrui Zhao <zhaotianrui@loongson.cn>
> Signed-off-by: xianglai li <lixianglai@loongson.cn>
> ---
>   meson.build                   |   1 +
>   target/loongarch/cpu.c        |   3 +
>   target/loongarch/cpu.h        |   2 +
>   target/loongarch/kvm.c        | 406 +++++++++++++++++++++++++++++++++-
>   target/loongarch/trace-events |  13 ++
>   target/loongarch/trace.h      |   1 +
>   6 files changed, 424 insertions(+), 2 deletions(-)
>   create mode 100644 target/loongarch/trace-events
>   create mode 100644 target/loongarch/trace.h


> +static int kvm_larch_getq(CPUState *cs, uint64_t reg_id,
> +                                 uint64_t *addr)
> +{
> +    struct kvm_one_reg csrreg = {
> +        .id = reg_id,
> +        .addr = (uintptr_t)addr
> +    };
> +
> +    return kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &csrreg);
> +}

This is kvm_get_one_reg().

> +static int kvm_larch_putq(CPUState *cs, uint64_t reg_id,
> +                                 uint64_t *addr)
> +{
> +    struct kvm_one_reg csrreg = {
> +        .id = reg_id,
> +        .addr = (uintptr_t)addr
> +    };
> +
> +    return kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &csrreg);
> +}

This is kvm_set_one_reg().

> +
> +#define KVM_GET_ONE_UREG64(cs, ret, regidx, addr)                 \
> +    ({                                                            \
> +        err = kvm_larch_getq(cs, KVM_IOC_CSRID(regidx), addr);    \
> +        if (err < 0) {                                            \
> +            ret = err;                                            \
> +            trace_kvm_failed_get_csr(regidx, strerror(errno));    \
> +        }                                                         \
> +    })
> +
> +#define KVM_PUT_ONE_UREG64(cs, ret, regidx, addr)                 \
> +    ({                                                            \
> +        err = kvm_larch_putq(cs, KVM_IOC_CSRID(regidx), addr);    \
> +        if (err < 0) {                                            \
> +            ret = err;                                            \
> +            trace_kvm_failed_put_csr(regidx, strerror(errno));    \
> +        }                                                         \
> +    })