[PATCH 8/9] RISC-V: KVM: Add ONE_REG interface for mvendorid, marchid, and mimpid

Anup Patel
2022-11-28T16:15:43Z

We add ONE_REG interface for VCPU mvendorid, marchid, and mimpid
so that KVM user-space can change this details to support migration
across heterogeneous hosts.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
arch/riscv/include/uapi/asm/kvm.h | 3 +++
arch/riscv/kvm/vcpu.c | 27 +++++++++++++++++++++++++++
2 files changed, 30 insertions(+)

diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h
index 8985ff234c01..92af6f3f057c 100644
--- a/arch/riscv/include/uapi/asm/kvm.h
+++ b/arch/riscv/include/uapi/asm/kvm.h
@@ -49,6 +49,9 @@ struct kvm_sregs {
struct kvm_riscv_config {
unsigned long isa;
unsigned long zicbom_block_size;
+ unsigned long mvendorid;
+ unsigned long marchid;
+ unsigned long mimpid;
};

/* CORE registers for KVM_GET_ONE_REG and KVM_SET_ONE_REG */
diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c
index 312a8a926867..7c08567097f0 100644
--- a/arch/riscv/kvm/vcpu.c
+++ b/arch/riscv/kvm/vcpu.c
@@ -276,6 +276,15 @@ static int kvm_riscv_vcpu_get_reg_config(struct kvm_vcpu *vcpu,
return -EINVAL;
reg_val = riscv_cbom_block_size;
break;
+ case KVM_REG_RISCV_CONFIG_REG(mvendorid):
+ reg_val = vcpu->arch.mvendorid;
+ break;
+ case KVM_REG_RISCV_CONFIG_REG(marchid):
+ reg_val = vcpu->arch.marchid;
+ break;
+ case KVM_REG_RISCV_CONFIG_REG(mimpid):
+ reg_val = vcpu->arch.mimpid;
+ break;
default:
return -EINVAL;
}
@@ -338,6 +347,24 @@ static int kvm_riscv_vcpu_set_reg_config(struct kvm_vcpu *vcpu,
break;
case KVM_REG_RISCV_CONFIG_REG(zicbom_block_size):
return -EOPNOTSUPP;
+ case KVM_REG_RISCV_CONFIG_REG(mvendorid):
+ if (!vcpu->arch.ran_atleast_once)
+ vcpu->arch.mvendorid = reg_val;
+ else
+ return -EBUSY;
+ break;
+ case KVM_REG_RISCV_CONFIG_REG(marchid):
+ if (!vcpu->arch.ran_atleast_once)
+ vcpu->arch.marchid = reg_val;
+ else
+ return -EBUSY;
+ break;
+ case KVM_REG_RISCV_CONFIG_REG(mimpid):
+ if (!vcpu->arch.ran_atleast_once)
+ vcpu->arch.mimpid = reg_val;
+ else
+ return -EBUSY;
+ break;
default:
return -EINVAL;
}
--
2.34.1