diff options
author | Anup Patel <anup.patel@wdc.com> | 2021-11-26 14:35:51 +0300 |
---|---|---|
committer | Anup Patel <anup@brainfault.org> | 2022-01-06 12:46:58 +0300 |
commit | a457fd5660efa9cf960d2461156a1025bfdb13fa (patch) | |
tree | 74381143d7ad54e9dd3238f35cc79257070a355d | |
parent | ef8949a986f0e325b1d535389101541849d611d3 (diff) | |
download | linux-a457fd5660efa9cf960d2461156a1025bfdb13fa.tar.xz |
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>
-rw-r--r-- | arch/riscv/include/asm/kvm_host.h | 1 | ||||
-rw-r--r-- | arch/riscv/kvm/mmu.c | 5 | ||||
-rw-r--r-- | arch/riscv/kvm/vm.c | 3 | ||||
-rw-r--r-- | include/uapi/linux/kvm.h | 1 |
4 files changed, 10 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); diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c index 5f2736c2e773..9af67dbdc66a 100644 --- a/arch/riscv/kvm/mmu.c +++ b/arch/riscv/kvm/mmu.c @@ -769,3 +769,8 @@ unsigned long kvm_riscv_stage2_mode(void) { return stage2_mode >> HGATP_MODE_SHIFT; } + +int kvm_riscv_stage2_gpa_bits(void) +{ + return stage2_gpa_bits; +} diff --git a/arch/riscv/kvm/vm.c b/arch/riscv/kvm/vm.c index 7619691d8953..c768f75279ef 100644 --- a/arch/riscv/kvm/vm.c +++ b/arch/riscv/kvm/vm.c @@ -74,6 +74,9 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) case KVM_CAP_NR_MEMSLOTS: r = KVM_USER_MEM_SLOTS; break; + case KVM_CAP_VM_GPA_BITS: + r = kvm_riscv_stage2_gpa_bits(); + break; default: r = 0; break; diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 1daa45268de2..469f05d69c8d 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -1131,6 +1131,7 @@ struct kvm_ppc_resize_hpt { #define KVM_CAP_EXIT_ON_EMULATION_FAILURE 204 #define KVM_CAP_ARM_MTE 205 #define KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM 206 +#define KVM_CAP_VM_GPA_BITS 207 #ifdef KVM_CAP_IRQ_ROUTING |