xref: /linux/arch/x86/include/asm/debugreg.h (revision d91517839e5d95adc0cf4b28caa7af62a71de526)
1 #ifndef _ASM_X86_DEBUGREG_H
2 #define _ASM_X86_DEBUGREG_H
3 
4 
5 #include <linux/bug.h>
6 #include <uapi/asm/debugreg.h>
7 
8 DECLARE_PER_CPU(unsigned long, cpu_dr7);
9 
10 #ifndef CONFIG_PARAVIRT
11 /*
12  * These special macros can be used to get or set a debugging register
13  */
14 #define get_debugreg(var, register)				\
15 	(var) = native_get_debugreg(register)
16 #define set_debugreg(value, register)				\
17 	native_set_debugreg(register, value)
18 #endif
19 
20 static inline unsigned long native_get_debugreg(int regno)
21 {
22 	unsigned long val = 0;	/* Damn you, gcc! */
23 
24 	switch (regno) {
25 	case 0:
26 		asm("mov %%db0, %0" :"=r" (val));
27 		break;
28 	case 1:
29 		asm("mov %%db1, %0" :"=r" (val));
30 		break;
31 	case 2:
32 		asm("mov %%db2, %0" :"=r" (val));
33 		break;
34 	case 3:
35 		asm("mov %%db3, %0" :"=r" (val));
36 		break;
37 	case 6:
38 		asm("mov %%db6, %0" :"=r" (val));
39 		break;
40 	case 7:
41 		asm("mov %%db7, %0" :"=r" (val));
42 		break;
43 	default:
44 		BUG();
45 	}
46 	return val;
47 }
48 
49 static inline void native_set_debugreg(int regno, unsigned long value)
50 {
51 	switch (regno) {
52 	case 0:
53 		asm("mov %0, %%db0"	::"r" (value));
54 		break;
55 	case 1:
56 		asm("mov %0, %%db1"	::"r" (value));
57 		break;
58 	case 2:
59 		asm("mov %0, %%db2"	::"r" (value));
60 		break;
61 	case 3:
62 		asm("mov %0, %%db3"	::"r" (value));
63 		break;
64 	case 6:
65 		asm("mov %0, %%db6"	::"r" (value));
66 		break;
67 	case 7:
68 		asm("mov %0, %%db7"	::"r" (value));
69 		break;
70 	default:
71 		BUG();
72 	}
73 }
74 
75 static inline void hw_breakpoint_disable(void)
76 {
77 	/* Zero the control register for HW Breakpoint */
78 	set_debugreg(0UL, 7);
79 
80 	/* Zero-out the individual HW breakpoint address registers */
81 	set_debugreg(0UL, 0);
82 	set_debugreg(0UL, 1);
83 	set_debugreg(0UL, 2);
84 	set_debugreg(0UL, 3);
85 }
86 
87 static inline int hw_breakpoint_active(void)
88 {
89 	return __this_cpu_read(cpu_dr7) & DR_GLOBAL_ENABLE_MASK;
90 }
91 
92 extern void aout_dump_debugregs(struct user *dump);
93 
94 extern void hw_breakpoint_restore(void);
95 
96 #ifdef CONFIG_X86_64
97 DECLARE_PER_CPU(int, debug_stack_usage);
98 static inline void debug_stack_usage_inc(void)
99 {
100 	__get_cpu_var(debug_stack_usage)++;
101 }
102 static inline void debug_stack_usage_dec(void)
103 {
104 	__get_cpu_var(debug_stack_usage)--;
105 }
106 int is_debug_stack(unsigned long addr);
107 void debug_stack_set_zero(void);
108 void debug_stack_reset(void);
109 #else /* !X86_64 */
110 static inline int is_debug_stack(unsigned long addr) { return 0; }
111 static inline void debug_stack_set_zero(void) { }
112 static inline void debug_stack_reset(void) { }
113 static inline void debug_stack_usage_inc(void) { }
114 static inline void debug_stack_usage_dec(void) { }
115 #endif /* X86_64 */
116 
117 
118 #endif /* _ASM_X86_DEBUGREG_H */
119