Hi, Bibo,
On Tue, Jul 30, 2024 at 3:57 PM Bibo Mao <maobibo@xxxxxxxxxxx> wrote:
>
> Every vcpu has separate LBT registers. And there are four scr registers,
> one flags and ftop register for LBT extension. When VM migrates, VMM
> needs to get LBT registers for every vcpu.
>
> Here macro KVM_REG_LOONGARCH_LBT is added for new vcpu lbt register type,
> the following macro is added to get/put LBT registers.
> KVM_REG_LOONGARCH_LBT_SCR0
> KVM_REG_LOONGARCH_LBT_SCR1
> KVM_REG_LOONGARCH_LBT_SCR2
> KVM_REG_LOONGARCH_LBT_SCR3
> KVM_REG_LOONGARCH_LBT_EFLAGS
> KVM_REG_LOONGARCH_LBT_FTOP
>
> Signed-off-by: Bibo Mao <maobibo@xxxxxxxxxxx>
> ---
> arch/loongarch/include/uapi/asm/kvm.h | 9 +++++
> arch/loongarch/kvm/vcpu.c | 56 +++++++++++++++++++++++++++
> 2 files changed, 65 insertions(+)
>
> diff --git a/arch/loongarch/include/uapi/asm/kvm.h b/arch/loongarch/include/uapi/asm/kvm.h
> index 49bafac8b22d..003fb766c93f 100644
> --- a/arch/loongarch/include/uapi/asm/kvm.h
> +++ b/arch/loongarch/include/uapi/asm/kvm.h
> @@ -64,6 +64,7 @@ struct kvm_fpu {
> #define KVM_REG_LOONGARCH_KVM (KVM_REG_LOONGARCH | 0x20000ULL)
> #define KVM_REG_LOONGARCH_FPSIMD (KVM_REG_LOONGARCH | 0x30000ULL)
> #define KVM_REG_LOONGARCH_CPUCFG (KVM_REG_LOONGARCH | 0x40000ULL)
> +#define KVM_REG_LOONGARCH_LBT (KVM_REG_LOONGARCH | 0x50000ULL)
> #define KVM_REG_LOONGARCH_MASK (KVM_REG_LOONGARCH | 0x70000ULL)
I think KVM_REG_LOONGARCH_MASK should contain all above register
classes, so should it be (KVM_REG_LOONGARCH | 0x370000ULL)?
> #define KVM_CSR_IDX_MASK 0x7fff
> #define KVM_CPUCFG_IDX_MASK 0x7fff
> @@ -77,6 +78,14 @@ struct kvm_fpu {
> /* Debugging: Special instruction for software breakpoint */
> #define KVM_REG_LOONGARCH_DEBUG_INST (KVM_REG_LOONGARCH_KVM | KVM_REG_SIZE_U64 | 3)
>
> +/* LBT registers */
> +#define KVM_REG_LOONGARCH_LBT_SCR0 (KVM_REG_LOONGARCH_LBT | KVM_REG_SIZE_U64 | 1)
> +#define KVM_REG_LOONGARCH_LBT_SCR1 (KVM_REG_LOONGARCH_LBT | KVM_REG_SIZE_U64 | 2)
> +#define KVM_REG_LOONGARCH_LBT_SCR2 (KVM_REG_LOONGARCH_LBT | KVM_REG_SIZE_U64 | 3)
> +#define KVM_REG_LOONGARCH_LBT_SCR3 (KVM_REG_LOONGARCH_LBT | KVM_REG_SIZE_U64 | 4)
> +#define KVM_REG_LOONGARCH_LBT_EFLAGS (KVM_REG_LOONGARCH_LBT | KVM_REG_SIZE_U64 | 5)
> +#define KVM_REG_LOONGARCH_LBT_FTOP (KVM_REG_LOONGARCH_LBT | KVM_REG_SIZE_U64 | 6)
FTOP is a 32bit register in other place of the kernel, is it correct
to use U64 here?
> +
> #define LOONGARCH_REG_SHIFT 3
> #define LOONGARCH_REG_64(TYPE, REG) (TYPE | KVM_REG_SIZE_U64 | (REG << LOONGARCH_REG_SHIFT))
> #define KVM_IOC_CSRID(REG) LOONGARCH_REG_64(KVM_REG_LOONGARCH_CSR, REG)
> diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c
> index b5324885a81a..b2500d4fa729 100644
> --- a/arch/loongarch/kvm/vcpu.c
> +++ b/arch/loongarch/kvm/vcpu.c
> @@ -597,6 +597,34 @@ static int kvm_get_one_reg(struct kvm_vcpu *vcpu,
> break;
> }
> break;
> + case KVM_REG_LOONGARCH_LBT:
What about adding FPU/LSX/LASX registers (if needed for migration) in
kvm_{get, set}_one_reg() here?
Huacai
> + if (!kvm_guest_has_lbt(&vcpu->arch))
> + return -ENXIO;
> +
> + switch (reg->id) {
> + case KVM_REG_LOONGARCH_LBT_SCR0:
> + *v = vcpu->arch.lbt.scr0;
> + break;
> + case KVM_REG_LOONGARCH_LBT_SCR1:
> + *v = vcpu->arch.lbt.scr1;
> + break;
> + case KVM_REG_LOONGARCH_LBT_SCR2:
> + *v = vcpu->arch.lbt.scr2;
> + break;
> + case KVM_REG_LOONGARCH_LBT_SCR3:
> + *v = vcpu->arch.lbt.scr3;
> + break;
> + case KVM_REG_LOONGARCH_LBT_EFLAGS:
> + *v = vcpu->arch.lbt.eflags;
> + break;
> + case KVM_REG_LOONGARCH_LBT_FTOP:
> + *v = vcpu->arch.fpu.ftop;
> + break;
> + default:
> + ret = -EINVAL;
> + break;
> + }
> + break;
> default:
> ret = -EINVAL;
> break;
> @@ -663,6 +691,34 @@ static int kvm_set_one_reg(struct kvm_vcpu *vcpu,
> break;
> }
> break;
> + case KVM_REG_LOONGARCH_LBT:
> + if (!kvm_guest_has_lbt(&vcpu->arch))
> + return -ENXIO;
> +
> + switch (reg->id) {
> + case KVM_REG_LOONGARCH_LBT_SCR0:
> + vcpu->arch.lbt.scr0 = v;
> + break;
> + case KVM_REG_LOONGARCH_LBT_SCR1:
> + vcpu->arch.lbt.scr1 = v;
> + break;
> + case KVM_REG_LOONGARCH_LBT_SCR2:
> + vcpu->arch.lbt.scr2 = v;
> + break;
> + case KVM_REG_LOONGARCH_LBT_SCR3:
> + vcpu->arch.lbt.scr3 = v;
> + break;
> + case KVM_REG_LOONGARCH_LBT_EFLAGS:
> + vcpu->arch.lbt.eflags = v;
> + break;
> + case KVM_REG_LOONGARCH_LBT_FTOP:
> + vcpu->arch.fpu.ftop = v;
> + break;
> + default:
> + ret = -EINVAL;
> + break;
> + }
> + break;
> default:
> ret = -EINVAL;
> break;
> --
> 2.39.3
>
