On Thu, Dec 14, 2023 at 3:46 PM Andrew Jones <ajones@xxxxxxxxxxxxxxxx> wrote: > > Some SBI extensions have state that needs to be saved / restored > when migrating the VM. Provide a get/set-one-reg register type > for SBI extension registers. Each SBI extension that uses this type > will have its own subtype. There are currently no subtypes defined. > The next patch introduces the first one. > > Signed-off-by: Andrew Jones <ajones@xxxxxxxxxxxxxxxx> LGTM. Reviewed-by: Anup Patel <anup@xxxxxxxxxxxxxx> Regards, Anup > --- > arch/riscv/include/asm/kvm_vcpu_sbi.h | 4 ++ > arch/riscv/include/uapi/asm/kvm.h | 3 ++ > arch/riscv/kvm/vcpu_onereg.c | 42 +++++++++++++++++-- > arch/riscv/kvm/vcpu_sbi.c | 58 +++++++++++++++++++++++++++ > 4 files changed, 103 insertions(+), 4 deletions(-) > > diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi.h b/arch/riscv/include/asm/kvm_vcpu_sbi.h > index 99c23bb37a37..dd60f73b5c36 100644 > --- a/arch/riscv/include/asm/kvm_vcpu_sbi.h > +++ b/arch/riscv/include/asm/kvm_vcpu_sbi.h > @@ -60,6 +60,10 @@ int kvm_riscv_vcpu_set_reg_sbi_ext(struct kvm_vcpu *vcpu, > const struct kvm_one_reg *reg); > int kvm_riscv_vcpu_get_reg_sbi_ext(struct kvm_vcpu *vcpu, > const struct kvm_one_reg *reg); > +int kvm_riscv_vcpu_set_reg_sbi(struct kvm_vcpu *vcpu, > + const struct kvm_one_reg *reg); > +int kvm_riscv_vcpu_get_reg_sbi(struct kvm_vcpu *vcpu, > + const struct kvm_one_reg *reg); > const struct kvm_vcpu_sbi_extension *kvm_vcpu_sbi_find_ext( > struct kvm_vcpu *vcpu, unsigned long extid); > bool riscv_vcpu_supports_sbi_ext(struct kvm_vcpu *vcpu, int idx); > diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h > index e961d79622fb..30f89a0e855f 100644 > --- a/arch/riscv/include/uapi/asm/kvm.h > +++ b/arch/riscv/include/uapi/asm/kvm.h > @@ -242,6 +242,9 @@ enum KVM_RISCV_SBI_EXT_ID { > #define KVM_REG_RISCV_VECTOR_REG(n) \ > ((n) + sizeof(struct __riscv_v_ext_state) / sizeof(unsigned long)) > > +/* Registers for specific SBI extensions are mapped as type 10 */ > +#define KVM_REG_RISCV_SBI (0x0a << KVM_REG_RISCV_TYPE_SHIFT) > + > /* Device Control API: RISC-V AIA */ > #define KVM_DEV_RISCV_APLIC_ALIGN 0x1000 > #define KVM_DEV_RISCV_APLIC_SIZE 0x4000 > diff --git a/arch/riscv/kvm/vcpu_onereg.c b/arch/riscv/kvm/vcpu_onereg.c > index 11cdbf844291..901480e73817 100644 > --- a/arch/riscv/kvm/vcpu_onereg.c > +++ b/arch/riscv/kvm/vcpu_onereg.c > @@ -961,6 +961,29 @@ static unsigned long num_sbi_ext_regs(struct kvm_vcpu *vcpu) > return copy_sbi_ext_reg_indices(vcpu, NULL); > } > > +static inline unsigned long num_sbi_regs(struct kvm_vcpu *vcpu) > +{ > + return 0; > +} > + > +static int copy_sbi_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices) > +{ > + int n = num_sbi_regs(vcpu); > + > + for (int i = 0; i < n; i++) { > + u64 reg = KVM_REG_RISCV | KVM_REG_SIZE_U64 | > + KVM_REG_RISCV_SBI | i; > + > + if (uindices) { > + if (put_user(reg, uindices)) > + return -EFAULT; > + uindices++; > + } > + } > + > + return n; > +} > + > static inline unsigned long num_vector_regs(const struct kvm_vcpu *vcpu) > { > if (!riscv_isa_extension_available(vcpu->arch.isa, v)) > @@ -1028,6 +1051,7 @@ unsigned long kvm_riscv_vcpu_num_regs(struct kvm_vcpu *vcpu) > res += num_vector_regs(vcpu); > res += num_isa_ext_regs(vcpu); > res += num_sbi_ext_regs(vcpu); > + res += num_sbi_regs(vcpu); > > return res; > } > @@ -1083,6 +1107,12 @@ int kvm_riscv_vcpu_copy_reg_indices(struct kvm_vcpu *vcpu, > ret = copy_sbi_ext_reg_indices(vcpu, uindices); > if (ret < 0) > return ret; > + uindices += ret; > + > + ret = copy_sbi_reg_indices(vcpu, uindices); > + if (ret < 0) > + return ret; > + uindices += ret; > > return 0; > } > @@ -1105,12 +1135,14 @@ int kvm_riscv_vcpu_set_reg(struct kvm_vcpu *vcpu, > case KVM_REG_RISCV_FP_D: > return kvm_riscv_vcpu_set_reg_fp(vcpu, reg, > KVM_REG_RISCV_FP_D); > + case KVM_REG_RISCV_VECTOR: > + return kvm_riscv_vcpu_set_reg_vector(vcpu, reg); > case KVM_REG_RISCV_ISA_EXT: > return kvm_riscv_vcpu_set_reg_isa_ext(vcpu, reg); > case KVM_REG_RISCV_SBI_EXT: > return kvm_riscv_vcpu_set_reg_sbi_ext(vcpu, reg); > - case KVM_REG_RISCV_VECTOR: > - return kvm_riscv_vcpu_set_reg_vector(vcpu, reg); > + case KVM_REG_RISCV_SBI: > + return kvm_riscv_vcpu_set_reg_sbi(vcpu, reg); > default: > break; > } > @@ -1136,12 +1168,14 @@ int kvm_riscv_vcpu_get_reg(struct kvm_vcpu *vcpu, > case KVM_REG_RISCV_FP_D: > return kvm_riscv_vcpu_get_reg_fp(vcpu, reg, > KVM_REG_RISCV_FP_D); > + case KVM_REG_RISCV_VECTOR: > + return kvm_riscv_vcpu_get_reg_vector(vcpu, reg); > case KVM_REG_RISCV_ISA_EXT: > return kvm_riscv_vcpu_get_reg_isa_ext(vcpu, reg); > case KVM_REG_RISCV_SBI_EXT: > return kvm_riscv_vcpu_get_reg_sbi_ext(vcpu, reg); > - case KVM_REG_RISCV_VECTOR: > - return kvm_riscv_vcpu_get_reg_vector(vcpu, reg); > + case KVM_REG_RISCV_SBI: > + return kvm_riscv_vcpu_get_reg_sbi(vcpu, reg); > default: > break; > } > diff --git a/arch/riscv/kvm/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c > index 088daaa23dd8..834176242ddf 100644 > --- a/arch/riscv/kvm/vcpu_sbi.c > +++ b/arch/riscv/kvm/vcpu_sbi.c > @@ -325,6 +325,64 @@ int kvm_riscv_vcpu_get_reg_sbi_ext(struct kvm_vcpu *vcpu, > return 0; > } > > +int kvm_riscv_vcpu_set_reg_sbi(struct kvm_vcpu *vcpu, > + const struct kvm_one_reg *reg) > +{ > + unsigned long __user *uaddr = > + (unsigned long __user *)(unsigned long)reg->addr; > + unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | > + KVM_REG_SIZE_MASK | > + KVM_REG_RISCV_SBI); > + unsigned long reg_subtype, reg_val; > + > + if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long)) > + return -EINVAL; > + > + if (copy_from_user(®_val, uaddr, KVM_REG_SIZE(reg->id))) > + return -EFAULT; > + > + reg_subtype = reg_num & KVM_REG_RISCV_SUBTYPE_MASK; > + reg_num &= ~KVM_REG_RISCV_SUBTYPE_MASK; > + > + switch (reg_subtype) { > + default: > + return -EINVAL; > + } > + > + return 0; > +} > + > +int kvm_riscv_vcpu_get_reg_sbi(struct kvm_vcpu *vcpu, > + const struct kvm_one_reg *reg) > +{ > + unsigned long __user *uaddr = > + (unsigned long __user *)(unsigned long)reg->addr; > + unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | > + KVM_REG_SIZE_MASK | > + KVM_REG_RISCV_SBI); > + unsigned long reg_subtype, reg_val; > + int ret; > + > + if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long)) > + return -EINVAL; > + > + reg_subtype = reg_num & KVM_REG_RISCV_SUBTYPE_MASK; > + reg_num &= ~KVM_REG_RISCV_SUBTYPE_MASK; > + > + switch (reg_subtype) { > + default: > + return -EINVAL; > + } > + > + if (ret) > + return ret; > + > + if (copy_to_user(uaddr, ®_val, KVM_REG_SIZE(reg->id))) > + return -EFAULT; > + > + return 0; > +} > + > const struct kvm_vcpu_sbi_extension *kvm_vcpu_sbi_find_ext( > struct kvm_vcpu *vcpu, unsigned long extid) > { > -- > 2.43.0 >