summaryrefslogtreecommitdiff
path: root/arch/x86/include/asm/kvm_para.h
blob: 57bc74e112f20936d6ee2601443892ecc083b533 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_KVM_PARA_H
#define _ASM_X86_KVM_PARA_H

#include <asm/processor.h>
#include <asm/alternative.h>
#include <linux/interrupt.h>
#include <uapi/asm/kvm_para.h>

#include <asm/tdx.h>

#ifdef CONFIG_KVM_GUEST
bool kvm_check_and_clear_guest_paused(void);
#else
static inline bool kvm_check_and_clear_guest_paused(void)
{
	return false;
}
#endif /* CONFIG_KVM_GUEST */

#define KVM_HYPERCALL \
        ALTERNATIVE("vmcall", "vmmcall", X86_FEATURE_VMMCALL)

/* For KVM hypercalls, a three-byte sequence of either the vmcall or the vmmcall
 * instruction.  The hypervisor may replace it with something else but only the
 * instructions are guaranteed to be supported.
 *
 * Up to four arguments may be passed in rbx, rcx, rdx, and rsi respectively.
 * The hypercall number should be placed in rax and the return value will be
 * placed in rax.  No other registers will be clobbered unless explicitly
 * noted by the particular hypercall.
 */

static inline long kvm_hypercall0(unsigned int nr)
{
	long ret;

	if (cpu_feature_enabled(X86_FEATURE_TDX_GUEST))
		return tdx_kvm_hypercall(nr, 0, 0, 0, 0);

	asm volatile(KVM_HYPERCALL
		     : "=a"(ret)
		     : "a"(nr)
		     : "memory");
	return ret;
}

static inline long kvm_hypercall1(unsigned int nr, unsigned long p1)
{
	long ret;

	if (cpu_feature_enabled(X86_FEATURE_TDX_GUEST))
		return tdx_kvm_hypercall(nr, p1, 0, 0, 0);

	asm volatile(KVM_HYPERCALL
		     : "=a"(ret)
		     : "a"(nr), "b"(p1)
		     : "memory");
	return ret;
}

static inline long kvm_hypercall2(unsigned int nr, unsigned long p1,
				  unsigned long p2)
{
	long ret;

	if (cpu_feature_enabled(X86_FEATURE_TDX_GUEST))
		return tdx_kvm_hypercall(nr, p1, p2, 0, 0);

	asm volatile(KVM_HYPERCALL
		     : "=a"(ret)
		     : "a"(nr), "b"(p1), "c"(p2)
		     : "memory");
	return ret;
}

static inline long kvm_hypercall3(unsigned int nr, unsigned long p1,
				  unsigned long p2, unsigned long p3)
{
	long ret;

	if (cpu_feature_enabled(X86_FEATURE_TDX_GUEST))
		return tdx_kvm_hypercall(nr, p1, p2, p3, 0);

	asm volatile(KVM_HYPERCALL
		     : "=a"(ret)
		     : "a"(nr), "b"(p1), "c"(p2), "d"(p3)
		     : "memory");
	return ret;
}

static inline long kvm_hypercall4(unsigned int nr, unsigned long p1,
				  unsigned long p2, unsigned long p3,
				  unsigned long p4)
{
	long ret;

	if (cpu_feature_enabled(X86_FEATURE_TDX_GUEST))
		return tdx_kvm_hypercall(nr, p1, p2, p3, p4);

	asm volatile(KVM_HYPERCALL
		     : "=a"(ret)
		     : "a"(nr), "b"(p1), "c"(p2), "d"(p3), "S"(p4)
		     : "memory");
	return ret;
}

static inline long kvm_sev_hypercall3(unsigned int nr, unsigned long p1,
				      unsigned long p2, unsigned long p3)
{
	long ret;

	asm volatile("vmmcall"
		     : "=a"(ret)
		     : "a"(nr), "b"(p1), "c"(p2), "d"(p3)
		     : "memory");
	return ret;
}

#ifdef CONFIG_KVM_GUEST
void kvmclock_init(void);
void kvmclock_disable(void);
bool kvm_para_available(void);
unsigned int kvm_arch_para_features(void);
unsigned int kvm_arch_para_hints(void);
void kvm_async_pf_task_wait_schedule(u32 token);
void kvm_async_pf_task_wake(u32 token);
u32 kvm_read_and_reset_apf_flags(void);
bool __kvm_handle_async_pf(struct pt_regs *regs, u32 token);

DECLARE_STATIC_KEY_FALSE(kvm_async_pf_enabled);

static __always_inline bool kvm_handle_async_pf(struct pt_regs *regs, u32 token)
{
	if (static_branch_unlikely(&kvm_async_pf_enabled))
		return __kvm_handle_async_pf(regs, token);
	else
		return false;
}

#ifdef CONFIG_PARAVIRT_SPINLOCKS
void __init kvm_spinlock_init(void);
#else /* !CONFIG_PARAVIRT_SPINLOCKS */
static inline void kvm_spinlock_init(void)
{
}
#endif /* CONFIG_PARAVIRT_SPINLOCKS */

#else /* CONFIG_KVM_GUEST */
#define kvm_async_pf_task_wait_schedule(T) do {} while(0)
#define kvm_async_pf_task_wake(T) do {} while(0)

static inline bool kvm_para_available(void)
{
	return false;
}

static inline unsigned int kvm_arch_para_features(void)
{
	return 0;
}

static inline unsigned int kvm_arch_para_hints(void)
{
	return 0;
}

static inline u32 kvm_read_and_reset_apf_flags(void)
{
	return 0;
}

static __always_inline bool kvm_handle_async_pf(struct pt_regs *regs, u32 token)
{
	return false;
}
#endif

#endif /* _ASM_X86_KVM_PARA_H */