xref: /linux/arch/x86/include/asm/irqflags.h (revision 1d33369db25eb7f37b7a8bd22d736888b4501a9c)
1 #ifndef _X86_IRQFLAGS_H_
2 #define _X86_IRQFLAGS_H_
3 
4 #include <asm/processor-flags.h>
5 
6 #ifndef __ASSEMBLY__
7 
8 /* Provide __cpuidle; we can't safely include <linux/cpu.h> */
9 #define __cpuidle __attribute__((__section__(".cpuidle.text")))
10 
11 /*
12  * Interrupt control:
13  */
14 
15 static inline unsigned long native_save_fl(void)
16 {
17 	unsigned long flags;
18 
19 	/*
20 	 * "=rm" is safe here, because "pop" adjusts the stack before
21 	 * it evaluates its effective address -- this is part of the
22 	 * documented behavior of the "pop" instruction.
23 	 */
24 	asm volatile("# __raw_save_flags\n\t"
25 		     "pushf ; pop %0"
26 		     : "=rm" (flags)
27 		     : /* no input */
28 		     : "memory");
29 
30 	return flags;
31 }
32 
33 static inline void native_restore_fl(unsigned long flags)
34 {
35 	asm volatile("push %0 ; popf"
36 		     : /* no output */
37 		     :"g" (flags)
38 		     :"memory", "cc");
39 }
40 
41 static inline void native_irq_disable(void)
42 {
43 	asm volatile("cli": : :"memory");
44 }
45 
46 static inline void native_irq_enable(void)
47 {
48 	asm volatile("sti": : :"memory");
49 }
50 
51 static inline __cpuidle void native_safe_halt(void)
52 {
53 	asm volatile("sti; hlt": : :"memory");
54 }
55 
56 static inline __cpuidle void native_halt(void)
57 {
58 	asm volatile("hlt": : :"memory");
59 }
60 
61 #endif
62 
63 #ifdef CONFIG_PARAVIRT
64 #include <asm/paravirt.h>
65 #else
66 #ifndef __ASSEMBLY__
67 #include <linux/types.h>
68 
69 static inline notrace unsigned long arch_local_save_flags(void)
70 {
71 	return native_save_fl();
72 }
73 
74 static inline notrace void arch_local_irq_restore(unsigned long flags)
75 {
76 	native_restore_fl(flags);
77 }
78 
79 static inline notrace void arch_local_irq_disable(void)
80 {
81 	native_irq_disable();
82 }
83 
84 static inline notrace void arch_local_irq_enable(void)
85 {
86 	native_irq_enable();
87 }
88 
89 /*
90  * Used in the idle loop; sti takes one instruction cycle
91  * to complete:
92  */
93 static inline __cpuidle void arch_safe_halt(void)
94 {
95 	native_safe_halt();
96 }
97 
98 /*
99  * Used when interrupts are already enabled or to
100  * shutdown the processor:
101  */
102 static inline __cpuidle void halt(void)
103 {
104 	native_halt();
105 }
106 
107 /*
108  * For spinlocks, etc:
109  */
110 static inline notrace unsigned long arch_local_irq_save(void)
111 {
112 	unsigned long flags = arch_local_save_flags();
113 	arch_local_irq_disable();
114 	return flags;
115 }
116 #else
117 
118 #define ENABLE_INTERRUPTS(x)	sti
119 #define DISABLE_INTERRUPTS(x)	cli
120 
121 #ifdef CONFIG_X86_64
122 #define SWAPGS	swapgs
123 /*
124  * Currently paravirt can't handle swapgs nicely when we
125  * don't have a stack we can rely on (such as a user space
126  * stack).  So we either find a way around these or just fault
127  * and emulate if a guest tries to call swapgs directly.
128  *
129  * Either way, this is a good way to document that we don't
130  * have a reliable stack. x86_64 only.
131  */
132 #define SWAPGS_UNSAFE_STACK	swapgs
133 
134 #define PARAVIRT_ADJUST_EXCEPTION_FRAME	/*  */
135 
136 #define INTERRUPT_RETURN	jmp native_iret
137 #define USERGS_SYSRET64				\
138 	swapgs;					\
139 	sysretq;
140 #define USERGS_SYSRET32				\
141 	swapgs;					\
142 	sysretl
143 
144 #else
145 #define INTERRUPT_RETURN		iret
146 #define ENABLE_INTERRUPTS_SYSEXIT	sti; sysexit
147 #define GET_CR0_INTO_EAX		movl %cr0, %eax
148 #endif
149 
150 
151 #endif /* __ASSEMBLY__ */
152 #endif /* CONFIG_PARAVIRT */
153 
154 #ifndef __ASSEMBLY__
155 static inline int arch_irqs_disabled_flags(unsigned long flags)
156 {
157 	return !(flags & X86_EFLAGS_IF);
158 }
159 
160 static inline int arch_irqs_disabled(void)
161 {
162 	unsigned long flags = arch_local_save_flags();
163 
164 	return arch_irqs_disabled_flags(flags);
165 }
166 #endif /* !__ASSEMBLY__ */
167 
168 #ifdef __ASSEMBLY__
169 #ifdef CONFIG_TRACE_IRQFLAGS
170 #  define TRACE_IRQS_ON		call trace_hardirqs_on_thunk;
171 #  define TRACE_IRQS_OFF	call trace_hardirqs_off_thunk;
172 #else
173 #  define TRACE_IRQS_ON
174 #  define TRACE_IRQS_OFF
175 #endif
176 #ifdef CONFIG_DEBUG_LOCK_ALLOC
177 #  ifdef CONFIG_X86_64
178 #    define LOCKDEP_SYS_EXIT		call lockdep_sys_exit_thunk
179 #    define LOCKDEP_SYS_EXIT_IRQ \
180 	TRACE_IRQS_ON; \
181 	sti; \
182 	call lockdep_sys_exit_thunk; \
183 	cli; \
184 	TRACE_IRQS_OFF;
185 #  else
186 #    define LOCKDEP_SYS_EXIT \
187 	pushl %eax;				\
188 	pushl %ecx;				\
189 	pushl %edx;				\
190 	call lockdep_sys_exit;			\
191 	popl %edx;				\
192 	popl %ecx;				\
193 	popl %eax;
194 #    define LOCKDEP_SYS_EXIT_IRQ
195 #  endif
196 #else
197 #  define LOCKDEP_SYS_EXIT
198 #  define LOCKDEP_SYS_EXIT_IRQ
199 #endif
200 #endif /* __ASSEMBLY__ */
201 
202 #endif
203