1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
4 */
5
6 #include <linux/kernel.h>
7 #include <linux/kvm_host.h>
8 #include <linux/sched/stat.h>
9 #include <asm/kvm_para.h>
10 #include <asm/paravirt.h>
11 #include "intc/ls3a_ipi.h"
12
kvm_virt_ipi(struct kvm_vcpu *vcpu)13 int kvm_virt_ipi(struct kvm_vcpu *vcpu)
14 {
15 int ret = 0;
16 u64 ipi_bitmap;
17 unsigned int min, action, cpu;
18
19 ipi_bitmap = vcpu->arch.gprs[REG_A1];
20 min = vcpu->arch.gprs[REG_A2];
21 action = vcpu->arch.gprs[REG_A3];
22
23 if (ipi_bitmap) {
24 cpu = find_first_bit((void *)&ipi_bitmap, BITS_PER_LONG);
25 while (cpu < BITS_PER_LONG) {
26 kvm_helper_send_ipi(vcpu, cpu + min, action);
27 cpu = find_next_bit((void *)&ipi_bitmap, BITS_PER_LONG, cpu + 1);
28 }
29 }
30
31 return ret;
32 }
33
kvm_save_notify(struct kvm_vcpu *vcpu)34 int kvm_save_notify(struct kvm_vcpu *vcpu)
35 {
36 unsigned long num, id, data;
37 struct gfn_to_pfn_cache *cache = &vcpu->arch.st.cache;
38
39 int ret = 0;
40
41 num = vcpu->arch.gprs[REG_A0];
42 id = vcpu->arch.gprs[REG_A1];
43 data = vcpu->arch.gprs[REG_A2];
44
45 switch (id) {
46 case KVM_FEATURE_STEAL_TIME:
47 if (!sched_info_on())
48 break;
49
50 if (vcpu->arch.st.guest_addr && (data == 0))
51 kvm_release_pfn(cache->pfn, cache->dirty, cache);
52
53 vcpu->arch.st.guest_addr = data;
54 kvm_debug("cpu :%d addr:%lx\n", vcpu->vcpu_id, data);
55 vcpu->arch.st.last_steal = current->sched_info.run_delay;
56 kvm_make_request(KVM_REQ_RECORD_STEAL, vcpu);
57 break;
58 default:
59 break;
60 };
61
62 return ret;
63 };
64
_kvm_pv_feature(struct kvm_vcpu *vcpu)65 static int _kvm_pv_feature(struct kvm_vcpu *vcpu)
66 {
67 int feature = vcpu->arch.gprs[REG_A1];
68 int ret = KVM_RET_NOT_SUPPORTED;
69 switch (feature) {
70 case KVM_FEATURE_STEAL_TIME:
71 if (sched_info_on())
72 ret = KVM_RET_SUC;
73 break;
74 case KVM_FEATURE_MULTI_IPI:
75 ret = KVM_RET_SUC;
76 break;
77 case KVM_FEATURE_PARAVIRT_SPINLOCK:
78 #ifdef CONFIG_PARAVIRT_SPINLOCKS
79 ret = KVM_RET_SUC;
80 #endif
81 break;
82 default:
83 break;
84 }
85 return ret;
86 }
87
kvm_pv_kick_cpu(struct kvm_vcpu *vcpu)88 static int kvm_pv_kick_cpu(struct kvm_vcpu *vcpu)
89 {
90 int cpu = vcpu->arch.gprs[REG_A1];
91 struct kvm_vcpu *dst_vcpu = vcpu->kvm->vcpus[cpu];
92 int ret = 0;
93
94 dst_vcpu->arch.pv.pv_unhalted = true;
95 kvm_make_request(KVM_REQ_EVENT, dst_vcpu);
96 kvm_vcpu_kick(dst_vcpu);
97
98 return ret;
99 }
100
101 /*
102 * hypcall emulation always return to guest, Caller should check retval.
103 */
_kvm_handle_pv_hcall(struct kvm_vcpu *vcpu)104 int _kvm_handle_pv_hcall(struct kvm_vcpu *vcpu)
105 {
106 unsigned long func = vcpu->arch.gprs[REG_A0];
107 int hyp_ret = KVM_RET_NOT_SUPPORTED;
108
109 switch (func) {
110 case KVM_HC_FUNC_FEATURE:
111 hyp_ret = _kvm_pv_feature(vcpu);
112 break;
113 case KVM_HC_FUNC_NOTIFY:
114 hyp_ret = kvm_save_notify(vcpu);
115 break;
116 case KVM_HC_FUNC_IPI:
117 hyp_ret = kvm_virt_ipi(vcpu);
118 break;
119 case KVM_HC_KICK_CPU:
120 hyp_ret = kvm_pv_kick_cpu(vcpu);
121 break;
122 default:
123 kvm_info("[%#lx] hvc func:%#lx unsupported\n", vcpu->arch.pc, func);
124 break;
125 };
126
127 vcpu->arch.gprs[REG_A0] = hyp_ret;
128
129 return RESUME_GUEST;
130 }
131