diff options
| -rw-r--r-- | arch/riscv/include/asm/kvm_vcpu_insn.h | 9 | ||||
| -rw-r--r-- | arch/riscv/kvm/vcpu_insn.c | 82 |
2 files changed, 82 insertions, 9 deletions
diff --git a/arch/riscv/include/asm/kvm_vcpu_insn.h b/arch/riscv/include/asm/kvm_vcpu_insn.h index 4e3ba4e84d0f..3351eb61a251 100644 --- a/arch/riscv/include/asm/kvm_vcpu_insn.h +++ b/arch/riscv/include/asm/kvm_vcpu_insn.h @@ -18,6 +18,15 @@ struct kvm_mmio_decode { int return_handled; }; +/* Return values used by function emulating a particular instruction */ +enum kvm_insn_return { + KVM_INSN_EXIT_TO_USER_SPACE = 0, + KVM_INSN_CONTINUE_NEXT_SEPC, + KVM_INSN_CONTINUE_SAME_SEPC, + KVM_INSN_ILLEGAL_TRAP, + KVM_INSN_VIRTUAL_TRAP +}; + void kvm_riscv_vcpu_wfi(struct kvm_vcpu *vcpu); int kvm_riscv_vcpu_virtual_insn(struct kvm_vcpu *vcpu, struct kvm_run *run, struct kvm_cpu_trap *trap); diff --git a/arch/riscv/kvm/vcpu_insn.c b/arch/riscv/kvm/vcpu_insn.c index be756879c2ee..75ca62a7fba5 100644 --- a/arch/riscv/kvm/vcpu_insn.c +++ b/arch/riscv/kvm/vcpu_insn.c @@ -118,8 +118,24 @@ (s32)(((insn) >> 7) & 0x1f)) #define MASK_FUNCT3 0x7000 -static int truly_illegal_insn(struct kvm_vcpu *vcpu, - struct kvm_run *run, +struct insn_func { + unsigned long mask; + unsigned long match; + /* + * Possible return values are as follows: + * 1) Returns < 0 for error case + * 2) Returns 0 for exit to user-space + * 3) Returns 1 to continue with next sepc + * 4) Returns 2 to continue with same sepc + * 5) Returns 3 to inject illegal instruction trap and continue + * 6) Returns 4 to inject virtual instruction trap and continue + * + * Use enum kvm_insn_return for return values + */ + int (*func)(struct kvm_vcpu *vcpu, struct kvm_run *run, ulong insn); +}; + +static int truly_illegal_insn(struct kvm_vcpu *vcpu, struct kvm_run *run, ulong insn) { struct kvm_cpu_trap utrap = { 0 }; @@ -128,6 +144,24 @@ static int truly_illegal_insn(struct kvm_vcpu *vcpu, utrap.sepc = vcpu->arch.guest_context.sepc; utrap.scause = EXC_INST_ILLEGAL; utrap.stval = insn; + utrap.htval = 0; + utrap.htinst = 0; + kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); + + return 1; +} + +static int truly_virtual_insn(struct kvm_vcpu *vcpu, struct kvm_run *run, + ulong insn) +{ + struct kvm_cpu_trap utrap = { 0 }; + + /* Redirect trap to Guest VCPU */ + utrap.sepc = vcpu->arch.guest_context.sepc; + utrap.scause = EXC_VIRTUAL_INST_FAULT; + utrap.stval = insn; + utrap.htval = 0; + utrap.htinst = 0; kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); return 1; @@ -148,18 +182,48 @@ void kvm_riscv_vcpu_wfi(struct kvm_vcpu *vcpu) } } -static int system_opcode_insn(struct kvm_vcpu *vcpu, - struct kvm_run *run, +static int wfi_insn(struct kvm_vcpu *vcpu, struct kvm_run *run, ulong insn) +{ + vcpu->stat.wfi_exit_stat++; + kvm_riscv_vcpu_wfi(vcpu); + return KVM_INSN_CONTINUE_NEXT_SEPC; +} + +static const struct insn_func system_opcode_funcs[] = { + { + .mask = INSN_MASK_WFI, + .match = INSN_MATCH_WFI, + .func = wfi_insn, + }, +}; + +static int system_opcode_insn(struct kvm_vcpu *vcpu, struct kvm_run *run, ulong insn) { - if ((insn & INSN_MASK_WFI) == INSN_MATCH_WFI) { - vcpu->stat.wfi_exit_stat++; - kvm_riscv_vcpu_wfi(vcpu); + int i, rc = KVM_INSN_ILLEGAL_TRAP; + const struct insn_func *ifn; + + for (i = 0; i < ARRAY_SIZE(system_opcode_funcs); i++) { + ifn = &system_opcode_funcs[i]; + if ((insn & ifn->mask) == ifn->match) { + rc = ifn->func(vcpu, run, insn); + break; + } + } + + switch (rc) { + case KVM_INSN_ILLEGAL_TRAP: + return truly_illegal_insn(vcpu, run, insn); + case KVM_INSN_VIRTUAL_TRAP: + return truly_virtual_insn(vcpu, run, insn); + case KVM_INSN_CONTINUE_NEXT_SEPC: vcpu->arch.guest_context.sepc += INSN_LEN(insn); - return 1; + break; + default: + break; } - return truly_illegal_insn(vcpu, run, insn); + return (rc <= 0) ? rc : 1; } /** |