xref: /openbmc/linux/arch/x86/include/asm/irqflags.h (revision 293d5b43)
1 #ifndef _X86_IRQFLAGS_H_
2 #define _X86_IRQFLAGS_H_
3 
4 #include <asm/processor-flags.h>
5 
6 #ifndef __ASSEMBLY__
7 /*
8  * Interrupt control:
9  */
10 
11 static inline unsigned long native_save_fl(void)
12 {
13 	unsigned long flags;
14 
15 	/*
16 	 * "=rm" is safe here, because "pop" adjusts the stack before
17 	 * it evaluates its effective address -- this is part of the
18 	 * documented behavior of the "pop" instruction.
19 	 */
20 	asm volatile("# __raw_save_flags\n\t"
21 		     "pushf ; pop %0"
22 		     : "=rm" (flags)
23 		     : /* no input */
24 		     : "memory");
25 
26 	return flags;
27 }
28 
29 static inline void native_restore_fl(unsigned long flags)
30 {
31 	asm volatile("push %0 ; popf"
32 		     : /* no output */
33 		     :"g" (flags)
34 		     :"memory", "cc");
35 }
36 
37 static inline void native_irq_disable(void)
38 {
39 	asm volatile("cli": : :"memory");
40 }
41 
42 static inline void native_irq_enable(void)
43 {
44 	asm volatile("sti": : :"memory");
45 }
46 
47 static inline void native_safe_halt(void)
48 {
49 	asm volatile("sti; hlt": : :"memory");
50 }
51 
52 static inline void native_halt(void)
53 {
54 	asm volatile("hlt": : :"memory");
55 }
56 
57 #endif
58 
59 #ifdef CONFIG_PARAVIRT
60 #include <asm/paravirt.h>
61 #else
62 #ifndef __ASSEMBLY__
63 #include <linux/types.h>
64 
65 static inline notrace unsigned long arch_local_save_flags(void)
66 {
67 	return native_save_fl();
68 }
69 
70 static inline notrace void arch_local_irq_restore(unsigned long flags)
71 {
72 	native_restore_fl(flags);
73 }
74 
75 static inline notrace void arch_local_irq_disable(void)
76 {
77 	native_irq_disable();
78 }
79 
80 static inline notrace void arch_local_irq_enable(void)
81 {
82 	native_irq_enable();
83 }
84 
85 /*
86  * Used in the idle loop; sti takes one instruction cycle
87  * to complete:
88  */
89 static inline void arch_safe_halt(void)
90 {
91 	native_safe_halt();
92 }
93 
94 /*
95  * Used when interrupts are already enabled or to
96  * shutdown the processor:
97  */
98 static inline void halt(void)
99 {
100 	native_halt();
101 }
102 
103 /*
104  * For spinlocks, etc:
105  */
106 static inline notrace unsigned long arch_local_irq_save(void)
107 {
108 	unsigned long flags = arch_local_save_flags();
109 	arch_local_irq_disable();
110 	return flags;
111 }
112 #else
113 
114 #define ENABLE_INTERRUPTS(x)	sti
115 #define DISABLE_INTERRUPTS(x)	cli
116 
117 #ifdef CONFIG_X86_64
118 #define SWAPGS	swapgs
119 /*
120  * Currently paravirt can't handle swapgs nicely when we
121  * don't have a stack we can rely on (such as a user space
122  * stack).  So we either find a way around these or just fault
123  * and emulate if a guest tries to call swapgs directly.
124  *
125  * Either way, this is a good way to document that we don't
126  * have a reliable stack. x86_64 only.
127  */
128 #define SWAPGS_UNSAFE_STACK	swapgs
129 
130 #define PARAVIRT_ADJUST_EXCEPTION_FRAME	/*  */
131 
132 #define INTERRUPT_RETURN	jmp native_iret
133 #define USERGS_SYSRET64				\
134 	swapgs;					\
135 	sysretq;
136 #define USERGS_SYSRET32				\
137 	swapgs;					\
138 	sysretl
139 
140 #else
141 #define INTERRUPT_RETURN		iret
142 #define ENABLE_INTERRUPTS_SYSEXIT	sti; sysexit
143 #define GET_CR0_INTO_EAX		movl %cr0, %eax
144 #endif
145 
146 
147 #endif /* __ASSEMBLY__ */
148 #endif /* CONFIG_PARAVIRT */
149 
150 #ifndef __ASSEMBLY__
151 static inline int arch_irqs_disabled_flags(unsigned long flags)
152 {
153 	return !(flags & X86_EFLAGS_IF);
154 }
155 
156 static inline int arch_irqs_disabled(void)
157 {
158 	unsigned long flags = arch_local_save_flags();
159 
160 	return arch_irqs_disabled_flags(flags);
161 }
162 #endif /* !__ASSEMBLY__ */
163 
164 #ifdef __ASSEMBLY__
165 #ifdef CONFIG_TRACE_IRQFLAGS
166 #  define TRACE_IRQS_ON		call trace_hardirqs_on_thunk;
167 #  define TRACE_IRQS_OFF	call trace_hardirqs_off_thunk;
168 #else
169 #  define TRACE_IRQS_ON
170 #  define TRACE_IRQS_OFF
171 #endif
172 #ifdef CONFIG_DEBUG_LOCK_ALLOC
173 #  ifdef CONFIG_X86_64
174 #    define LOCKDEP_SYS_EXIT		call lockdep_sys_exit_thunk
175 #    define LOCKDEP_SYS_EXIT_IRQ \
176 	TRACE_IRQS_ON; \
177 	sti; \
178 	call lockdep_sys_exit_thunk; \
179 	cli; \
180 	TRACE_IRQS_OFF;
181 #  else
182 #    define LOCKDEP_SYS_EXIT \
183 	pushl %eax;				\
184 	pushl %ecx;				\
185 	pushl %edx;				\
186 	call lockdep_sys_exit;			\
187 	popl %edx;				\
188 	popl %ecx;				\
189 	popl %eax;
190 #    define LOCKDEP_SYS_EXIT_IRQ
191 #  endif
192 #else
193 #  define LOCKDEP_SYS_EXIT
194 #  define LOCKDEP_SYS_EXIT_IRQ
195 #endif
196 #endif /* __ASSEMBLY__ */
197 
198 #endif
199