| rjw | 1f88458 | 2022-01-06 17:20:42 +0800 | [diff] [blame^] | 1 | /* |
| 2 | * This file is subject to the terms and conditions of the GNU General Public |
| 3 | * License. See the file "COPYING" in the main directory of this archive |
| 4 | * for more details. |
| 5 | * |
| 6 | * KVM/MIPS: Hypercall handling. |
| 7 | * |
| 8 | * Copyright (C) 2015 Imagination Technologies Ltd. |
| 9 | */ |
| 10 | |
| 11 | #include <linux/kernel.h> |
| 12 | #include <linux/kvm_host.h> |
| 13 | #include <linux/kvm_para.h> |
| 14 | |
| 15 | #define MAX_HYPCALL_ARGS 4 |
| 16 | |
| 17 | enum emulation_result kvm_mips_emul_hypcall(struct kvm_vcpu *vcpu, |
| 18 | union mips_instruction inst) |
| 19 | { |
| 20 | unsigned int code = (inst.co_format.code >> 5) & 0x3ff; |
| 21 | |
| 22 | kvm_debug("[%#lx] HYPCALL %#03x\n", vcpu->arch.pc, code); |
| 23 | |
| 24 | switch (code) { |
| 25 | case 0: |
| 26 | return EMULATE_HYPERCALL; |
| 27 | default: |
| 28 | return EMULATE_FAIL; |
| 29 | }; |
| 30 | } |
| 31 | |
| 32 | static int kvm_mips_hypercall(struct kvm_vcpu *vcpu, unsigned long num, |
| 33 | const unsigned long *args, unsigned long *hret) |
| 34 | { |
| 35 | /* Report unimplemented hypercall to guest */ |
| 36 | *hret = -KVM_ENOSYS; |
| 37 | return RESUME_GUEST; |
| 38 | } |
| 39 | |
| 40 | int kvm_mips_handle_hypcall(struct kvm_vcpu *vcpu) |
| 41 | { |
| 42 | unsigned long num, args[MAX_HYPCALL_ARGS]; |
| 43 | |
| 44 | /* read hypcall number and arguments */ |
| 45 | num = vcpu->arch.gprs[2]; /* v0 */ |
| 46 | args[0] = vcpu->arch.gprs[4]; /* a0 */ |
| 47 | args[1] = vcpu->arch.gprs[5]; /* a1 */ |
| 48 | args[2] = vcpu->arch.gprs[6]; /* a2 */ |
| 49 | args[3] = vcpu->arch.gprs[7]; /* a3 */ |
| 50 | |
| 51 | return kvm_mips_hypercall(vcpu, num, |
| 52 | args, &vcpu->arch.gprs[2] /* v0 */); |
| 53 | } |