xref: /openbmc/linux/arch/x86/include/asm/irqflags.h (revision 12eb4683)
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	iretq
133 #define USERGS_SYSRET64				\
134 	swapgs;					\
135 	sysretq;
136 #define USERGS_SYSRET32				\
137 	swapgs;					\
138 	sysretl
139 #define ENABLE_INTERRUPTS_SYSEXIT32		\
140 	swapgs;					\
141 	sti;					\
142 	sysexit
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 
167 #else
168 
169 #ifdef CONFIG_X86_64
170 #define ARCH_LOCKDEP_SYS_EXIT		call lockdep_sys_exit_thunk
171 #define ARCH_LOCKDEP_SYS_EXIT_IRQ	\
172 	TRACE_IRQS_ON; \
173 	sti; \
174 	SAVE_REST; \
175 	LOCKDEP_SYS_EXIT; \
176 	RESTORE_REST; \
177 	cli; \
178 	TRACE_IRQS_OFF;
179 
180 #else
181 #define ARCH_LOCKDEP_SYS_EXIT			\
182 	pushl %eax;				\
183 	pushl %ecx;				\
184 	pushl %edx;				\
185 	call lockdep_sys_exit;			\
186 	popl %edx;				\
187 	popl %ecx;				\
188 	popl %eax;
189 
190 #define ARCH_LOCKDEP_SYS_EXIT_IRQ
191 #endif
192 
193 #ifdef CONFIG_TRACE_IRQFLAGS
194 #  define TRACE_IRQS_ON		call trace_hardirqs_on_thunk;
195 #  define TRACE_IRQS_OFF	call trace_hardirqs_off_thunk;
196 #else
197 #  define TRACE_IRQS_ON
198 #  define TRACE_IRQS_OFF
199 #endif
200 #ifdef CONFIG_DEBUG_LOCK_ALLOC
201 #  define LOCKDEP_SYS_EXIT	ARCH_LOCKDEP_SYS_EXIT
202 #  define LOCKDEP_SYS_EXIT_IRQ	ARCH_LOCKDEP_SYS_EXIT_IRQ
203 # else
204 #  define LOCKDEP_SYS_EXIT
205 #  define LOCKDEP_SYS_EXIT_IRQ
206 # endif
207 
208 #endif /* __ASSEMBLY__ */
209 #endif
210