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 extern void kvmclock_init(void);
11
12 #ifdef CONFIG_KVM_GUEST
13 bool kvm_check_and_clear_guest_paused(void);
14 #else
kvm_check_and_clear_guest_paused(void)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
kvm_hypercall0(unsigned int nr)34 static inline long kvm_hypercall0(unsigned int nr)
35 {
36 long ret;
37 asm volatile(KVM_HYPERCALL
38 : "=a"(ret)
39 : "a"(nr)
40 : "memory");
41 return ret;
42 }
43
kvm_hypercall1(unsigned int nr,unsigned long p1)44 static inline long kvm_hypercall1(unsigned int nr, unsigned long p1)
45 {
46 long ret;
47 asm volatile(KVM_HYPERCALL
48 : "=a"(ret)
49 : "a"(nr), "b"(p1)
50 : "memory");
51 return ret;
52 }
53
kvm_hypercall2(unsigned int nr,unsigned long p1,unsigned long p2)54 static inline long kvm_hypercall2(unsigned int nr, unsigned long p1,
55 unsigned long p2)
56 {
57 long ret;
58 asm volatile(KVM_HYPERCALL
59 : "=a"(ret)
60 : "a"(nr), "b"(p1), "c"(p2)
61 : "memory");
62 return ret;
63 }
64
kvm_hypercall3(unsigned int nr,unsigned long p1,unsigned long p2,unsigned long p3)65 static inline long kvm_hypercall3(unsigned int nr, unsigned long p1,
66 unsigned long p2, unsigned long p3)
67 {
68 long ret;
69 asm volatile(KVM_HYPERCALL
70 : "=a"(ret)
71 : "a"(nr), "b"(p1), "c"(p2), "d"(p3)
72 : "memory");
73 return ret;
74 }
75
kvm_hypercall4(unsigned int nr,unsigned long p1,unsigned long p2,unsigned long p3,unsigned long p4)76 static inline long kvm_hypercall4(unsigned int nr, unsigned long p1,
77 unsigned long p2, unsigned long p3,
78 unsigned long p4)
79 {
80 long ret;
81 asm volatile(KVM_HYPERCALL
82 : "=a"(ret)
83 : "a"(nr), "b"(p1), "c"(p2), "d"(p3), "S"(p4)
84 : "memory");
85 return ret;
86 }
87
88 #ifdef CONFIG_KVM_GUEST
89 bool kvm_para_available(void);
90 unsigned int kvm_arch_para_features(void);
91 unsigned int kvm_arch_para_hints(void);
92 void kvm_async_pf_task_wait_schedule(u32 token);
93 void kvm_async_pf_task_wake(u32 token);
94 u32 kvm_read_and_reset_apf_flags(void);
95 void kvm_disable_steal_time(void);
96 bool __kvm_handle_async_pf(struct pt_regs *regs, u32 token);
97
98 DECLARE_STATIC_KEY_FALSE(kvm_async_pf_enabled);
99
kvm_handle_async_pf(struct pt_regs * regs,u32 token)100 static __always_inline bool kvm_handle_async_pf(struct pt_regs *regs, u32 token)
101 {
102 if (static_branch_unlikely(&kvm_async_pf_enabled))
103 return __kvm_handle_async_pf(regs, token);
104 else
105 return false;
106 }
107
108 #ifdef CONFIG_PARAVIRT_SPINLOCKS
109 void __init kvm_spinlock_init(void);
110 #else /* !CONFIG_PARAVIRT_SPINLOCKS */
kvm_spinlock_init(void)111 static inline void kvm_spinlock_init(void)
112 {
113 }
114 #endif /* CONFIG_PARAVIRT_SPINLOCKS */
115
116 #else /* CONFIG_KVM_GUEST */
117 #define kvm_async_pf_task_wait_schedule(T) do {} while(0)
118 #define kvm_async_pf_task_wake(T) do {} while(0)
119
kvm_para_available(void)120 static inline bool kvm_para_available(void)
121 {
122 return false;
123 }
124
kvm_arch_para_features(void)125 static inline unsigned int kvm_arch_para_features(void)
126 {
127 return 0;
128 }
129
kvm_arch_para_hints(void)130 static inline unsigned int kvm_arch_para_hints(void)
131 {
132 return 0;
133 }
134
kvm_read_and_reset_apf_flags(void)135 static inline u32 kvm_read_and_reset_apf_flags(void)
136 {
137 return 0;
138 }
139
kvm_disable_steal_time(void)140 static inline void kvm_disable_steal_time(void)
141 {
142 return;
143 }
144
kvm_handle_async_pf(struct pt_regs * regs,u32 token)145 static __always_inline bool kvm_handle_async_pf(struct pt_regs *regs, u32 token)
146 {
147 return false;
148 }
149 #endif
150
151 #endif /* _ASM_X86_KVM_PARA_H */
152