RISC-V: KVM: Add VM capability to allow userspace get GPA bits

The number of GPA bits supported for a RISC-V Guest/VM is based on the
MMU mode used by the G-stage translation. The KVM RISC-V will detect and
use the best possible MMU mode for the G-stage in kvm_arch_init().

We add a generic VM capability KVM_CAP_VM_GPA_BITS which can be used by
the KVM userspace to get the number of GPA (guest physical address) bits
supported for a Guest/VM.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-and-tested-by: Atish Patra <atishp@rivosinc.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/arch/riscv/include/asm/kvm_host.h b/arch/riscv/include/asm/kvm_host.h
index 52e19888ce43..99ef6a120617 100644
--- a/arch/riscv/include/asm/kvm_host.h
+++ b/arch/riscv/include/asm/kvm_host.h
@@ -218,6 +218,7 @@ void kvm_riscv_stage2_free_pgd(struct kvm *kvm);
 void kvm_riscv_stage2_update_hgatp(struct kvm_vcpu *vcpu);
 void kvm_riscv_stage2_mode_detect(void);
 unsigned long kvm_riscv_stage2_mode(void);
+int kvm_riscv_stage2_gpa_bits(void);
 
 void kvm_riscv_stage2_vmid_detect(void);
 unsigned long kvm_riscv_stage2_vmid_bits(void);