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
13bool kvm_check_and_clear_guest_paused(void);
14#else
15static 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
34static 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, p1: 0, p2: 0, p3: 0, p4: 0);
40
41 asm volatile(KVM_HYPERCALL
42 : "=a"(ret)
43 : "a"(nr)
44 : "memory");
45 return ret;
46}
47
48static 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, p2: 0, p3: 0, p4: 0);
54
55 asm volatile(KVM_HYPERCALL
56 : "=a"(ret)
57 : "a"(nr), "b"(p1)
58 : "memory");
59 return ret;
60}
61
62static 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, p3: 0, p4: 0);
69
70 asm volatile(KVM_HYPERCALL
71 : "=a"(ret)
72 : "a"(nr), "b"(p1), "c"(p2)
73 : "memory");
74 return ret;
75}
76
77static 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, p4: 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
92static 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
108static 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
121void kvmclock_init(void);
122void kvmclock_disable(void);
123bool kvm_para_available(void);
124unsigned int kvm_arch_para_features(void);
125unsigned int kvm_arch_para_hints(void);
126void kvm_async_pf_task_wait_schedule(u32 token);
127u32 kvm_read_and_reset_apf_flags(void);
128bool __kvm_handle_async_pf(struct pt_regs *regs, u32 token);
129
130DECLARE_STATIC_KEY_FALSE(kvm_async_pf_enabled);
131
132static __always_inline bool kvm_handle_async_pf(struct pt_regs *regs, u32 token)
133{
134 if (static_branch_unlikely(&kvm_async_pf_enabled))
135 return __kvm_handle_async_pf(regs, token);
136 else
137 return false;
138}
139
140#ifdef CONFIG_PARAVIRT_SPINLOCKS
141void __init kvm_spinlock_init(void);
142#else /* !CONFIG_PARAVIRT_SPINLOCKS */
143static inline void kvm_spinlock_init(void)
144{
145}
146#endif /* CONFIG_PARAVIRT_SPINLOCKS */
147
148#else /* CONFIG_KVM_GUEST */
149#define kvm_async_pf_task_wait_schedule(T) do {} while(0)
150
151static inline bool kvm_para_available(void)
152{
153 return false;
154}
155
156static inline unsigned int kvm_arch_para_features(void)
157{
158 return 0;
159}
160
161static inline unsigned int kvm_arch_para_hints(void)
162{
163 return 0;
164}
165
166static inline u32 kvm_read_and_reset_apf_flags(void)
167{
168 return 0;
169}
170
171static __always_inline bool kvm_handle_async_pf(struct pt_regs *regs, u32 token)
172{
173 return false;
174}
175#endif
176
177#endif /* _ASM_X86_KVM_PARA_H */
178

source code of linux/arch/x86/include/asm/kvm_para.h