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| author | Daniel Henrique Barboza <dbarboza@ventanamicro.com> | 2023-07-29 00:01:22 +0300 |
|---|---|---|
| committer | Anup Patel <anup@brainfault.org> | 2023-08-08 14:55:40 +0300 |
| commit | 2776421e6839b67c34261861b169b7ee737b4c00 (patch) | |
| tree | 7a816fa478f769c35eff8d03ef825e745d520c59 /arch/riscv/kvm/vcpu_onereg.c | |
| parent | d2064d4a6e3a565879da196947fb35cc7b1f3256 (diff) | |
| download | linux-2776421e6839b67c34261861b169b7ee737b4c00.tar.xz | |
RISC-V: KVM: provide UAPI for host SATP mode
KVM userspaces need to be aware of the host SATP to allow them to
advertise it back to the guest OS.
Since this information is used to build the guest FDT we can't wait for
the SATP reg to be readable. We just need to read the SATP mode, thus
we can use the existing 'satp_mode' global that represents the SATP reg
with MODE set and both ASID and PPN cleared. E.g. for a 32 bit host
running with sv32 satp_mode is 0x80000000, for a 64 bit host running
sv57 satp_mode is 0xa000000000000000, and so on.
Add a new userspace virtual config register 'satp_mode' to allow
userspace to read the current SATP mode the host is using with
GET_ONE_REG API before spinning the vcpu.
'satp_mode' can't be changed via KVM, so SET_ONE_REG is allowed as long
as userspace writes the existing 'satp_mode'.
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Anup Patel <anup@brainfault.org>
Diffstat (limited to 'arch/riscv/kvm/vcpu_onereg.c')
| -rw-r--r-- | arch/riscv/kvm/vcpu_onereg.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/arch/riscv/kvm/vcpu_onereg.c b/arch/riscv/kvm/vcpu_onereg.c index 0dc2c2cecb45..85773e858120 100644 --- a/arch/riscv/kvm/vcpu_onereg.c +++ b/arch/riscv/kvm/vcpu_onereg.c @@ -152,6 +152,9 @@ static int kvm_riscv_vcpu_get_reg_config(struct kvm_vcpu *vcpu, case KVM_REG_RISCV_CONFIG_REG(mimpid): reg_val = vcpu->arch.mimpid; break; + case KVM_REG_RISCV_CONFIG_REG(satp_mode): + reg_val = satp_mode >> SATP_MODE_SHIFT; + break; default: return -EINVAL; } @@ -234,6 +237,10 @@ static int kvm_riscv_vcpu_set_reg_config(struct kvm_vcpu *vcpu, else return -EBUSY; break; + case KVM_REG_RISCV_CONFIG_REG(satp_mode): + if (reg_val != (satp_mode >> SATP_MODE_SHIFT)) + return -EINVAL; + break; default: return -EINVAL; } |