1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_KVM_PARA_H
3 #define _ASM_X86_KVM_PARA_H
4
5 #include <asm/processor.h>
6 #include <asm/alternative.h>
7 #include <linux/interrupt.h>
8 #include <uapi/asm/kvm_para.h>
9
10 #include <asm/tdx.h>
11
12 #ifdef CONFIG_KVM_GUEST
13 bool kvm_check_and_clear_guest_paused(void);
14 #else
15 static inline bool kvm_check_and_clear_guest_paused(void)
16 {
17 return false;
18 }
19 #endif /* CONFIG_KVM_GUEST */
20
21 #define KVM_HYPERCALL \
22 ALTERNATIVE("vmcall", "vmmcall", X86_FEATURE_VMMCALL)
23
24 /* For KVM hypercalls, a three-byte sequence of either the vmcall or the vmmcall
25 * instruction. The hypervisor may replace it with something else but only the
26 * instructions are guaranteed to be supported.
27 *
28 * Up to four arguments may be passed in rbx, rcx, rdx, and rsi respectively.
29 * The hypercall number should be placed in rax and the return value will be
30 * placed in rax. No other registers will be clobbered unless explicitly
31 * noted by the particular hypercall.
32 */
33
34 static inline long kvm_hypercall0(unsigned int nr)
35 {
36 long ret;
37
38 if (cpu_feature_enabled(X86_FEATURE_TDX_GUEST))
39 return tdx_kvm_hypercall(nr, 0, 0, 0, 0);
40
41 asm volatile(KVM_HYPERCALL
42 : "=a"(ret)
43 : "a"(nr)
44 : "memory");
45 return ret;
46 }
47
48 static inline long kvm_hypercall1(unsigned int nr, unsigned long p1)
49 {
50 long ret;
51
52 if (cpu_feature_enabled(X86_FEATURE_TDX_GUEST))
53 return tdx_kvm_hypercall(nr, p1, 0, 0, 0);
54
55 asm volatile(KVM_HYPERCALL
56 : "=a"(ret)
57 : "a"(nr), "b"(p1)
58 : "memory");
59 return ret;
60 }
61
62 static inline long kvm_hypercall2(unsigned int nr, unsigned long p1,
63 unsigned long p2)
64 {
65 long ret;
66
67 if (cpu_feature_enabled(X86_FEATURE_TDX_GUEST))
68 return tdx_kvm_hypercall(nr, p1, p2, 0, 0);
69
70 asm volatile(KVM_HYPERCALL
71 : "=a"(ret)
72 : "a"(nr), "b"(p1), "c"(p2)
73 : "memory");
74 return ret;
75 }
76
77 static inline long kvm_hypercall3(unsigned int nr, unsigned long p1,
78 unsigned long p2, unsigned long p3)
79 {
80 long ret;
81
82 if (cpu_feature_enabled(X86_FEATURE_TDX_GUEST))
83 return tdx_kvm_hypercall(nr, p1, p2, p3, 0);
84
85 asm volatile(KVM_HYPERCALL
86 : "=a"(ret)
87 : "a"(nr), "b"(p1), "c"(p2), "d"(p3)
88 : "memory");
89 return ret;
90 }
91
92 static inline long kvm_hypercall4(unsigned int nr, unsigned long p1,
93 unsigned long p2, unsigned long p3,
94 unsigned long p4)
95 {
96 long ret;
97
98 if (cpu_feature_enabled(X86_FEATURE_TDX_GUEST))
99 return tdx_kvm_hypercall(nr, p1, p2, p3, p4);
100
101 asm volatile(KVM_HYPERCALL
102 : "=a"(ret)
103 : "a"(nr), "b"(p1), "c"(p2), "d"(p3), "S"(p4)
104 : "memory");
105 return ret;
106 }
107
108 static inline long kvm_sev_hypercall3(unsigned int nr, unsigned long p1,
109 unsigned long p2, unsigned long p3)
110 {
111 long ret;
112
113 asm volatile("vmmcall"
114 : "=a"(ret)
115 : "a"(nr), "b"(p1), "c"(p2), "d"(p3)
116 : "memory");
117 return ret;
118 }
119
120 #ifdef CONFIG_KVM_GUEST
121 void kvmclock_init(void);
122 void kvmclock_disable(void);
123 bool kvm_para_available(void);
124 unsigned int kvm_arch_para_features(void);
125 unsigned int kvm_arch_para_hints(void);
126 void kvm_async_pf_task_wait_schedule(u32 token);
127 void kvm_async_pf_task_wake(u32 token);
128 u32 kvm_read_and_reset_apf_flags(void);
129 bool __kvm_handle_async_pf(struct pt_regs *regs, u32 token);
130
131 DECLARE_STATIC_KEY_FALSE(kvm_async_pf_enabled);
132
133 static __always_inline bool kvm_handle_async_pf(struct pt_regs *regs, u32 token)
134 {
135 if (static_branch_unlikely(&kvm_async_pf_enabled))
136 return __kvm_handle_async_pf(regs, token);
137 else
138 return false;
139 }
140
141 #ifdef CONFIG_PARAVIRT_SPINLOCKS
142 void __init kvm_spinlock_init(void);
143 #else /* !CONFIG_PARAVIRT_SPINLOCKS */
144 static inline void kvm_spinlock_init(void)
145 {
146 }
147 #endif /* CONFIG_PARAVIRT_SPINLOCKS */
148
149 #else /* CONFIG_KVM_GUEST */
150 #define kvm_async_pf_task_wait_schedule(T) do {} while(0)
151 #define kvm_async_pf_task_wake(T) do {} while(0)
152
153 static inline bool kvm_para_available(void)
154 {
155 return false;
156 }
157
158 static inline unsigned int kvm_arch_para_features(void)
159 {
160 return 0;
161 }
162
163 static inline unsigned int kvm_arch_para_hints(void)
164 {
165 return 0;
166 }
167
168 static inline u32 kvm_read_and_reset_apf_flags(void)
169 {
170 return 0;
171 }
172
173 static __always_inline bool kvm_handle_async_pf(struct pt_regs *regs, u32 token)
174 {
175 return false;
176 }
177 #endif
178
179 #endif /* _ASM_X86_KVM_PARA_H */
180
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