1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_DEBUGREG_H
3 #define _ASM_X86_DEBUGREG_H
4
5
6 #include <linux/bug.h>
7 #include <uapi/asm/debugreg.h>
8
9 DECLARE_PER_CPU(unsigned long, cpu_dr7);
10
11 #ifndef CONFIG_PARAVIRT
12 /*
13 * These special macros can be used to get or set a debugging register
14 */
15 #define get_debugreg(var, register) \
16 (var) = native_get_debugreg(register)
17 #define set_debugreg(value, register) \
18 native_set_debugreg(register, value)
19 #endif
20
native_get_debugreg(int regno)21 static inline unsigned long native_get_debugreg(int regno)
22 {
23 unsigned long val = 0; /* Damn you, gcc! */
24
25 switch (regno) {
26 case 0:
27 asm("mov %%db0, %0" :"=r" (val));
28 break;
29 case 1:
30 asm("mov %%db1, %0" :"=r" (val));
31 break;
32 case 2:
33 asm("mov %%db2, %0" :"=r" (val));
34 break;
35 case 3:
36 asm("mov %%db3, %0" :"=r" (val));
37 break;
38 case 6:
39 asm("mov %%db6, %0" :"=r" (val));
40 break;
41 case 7:
42 asm("mov %%db7, %0" :"=r" (val));
43 break;
44 default:
45 BUG();
46 }
47 return val;
48 }
49
native_set_debugreg(int regno,unsigned long value)50 static inline void native_set_debugreg(int regno, unsigned long value)
51 {
52 switch (regno) {
53 case 0:
54 asm("mov %0, %%db0" ::"r" (value));
55 break;
56 case 1:
57 asm("mov %0, %%db1" ::"r" (value));
58 break;
59 case 2:
60 asm("mov %0, %%db2" ::"r" (value));
61 break;
62 case 3:
63 asm("mov %0, %%db3" ::"r" (value));
64 break;
65 case 6:
66 asm("mov %0, %%db6" ::"r" (value));
67 break;
68 case 7:
69 asm("mov %0, %%db7" ::"r" (value));
70 break;
71 default:
72 BUG();
73 }
74 }
75
hw_breakpoint_disable(void)76 static inline void hw_breakpoint_disable(void)
77 {
78 /* Zero the control register for HW Breakpoint */
79 set_debugreg(0UL, 7);
80
81 /* Zero-out the individual HW breakpoint address registers */
82 set_debugreg(0UL, 0);
83 set_debugreg(0UL, 1);
84 set_debugreg(0UL, 2);
85 set_debugreg(0UL, 3);
86 }
87
hw_breakpoint_active(void)88 static inline int hw_breakpoint_active(void)
89 {
90 return __this_cpu_read(cpu_dr7) & DR_GLOBAL_ENABLE_MASK;
91 }
92
93 extern void aout_dump_debugregs(struct user *dump);
94
95 extern void hw_breakpoint_restore(void);
96
97 #ifdef CONFIG_X86_64
98 DECLARE_PER_CPU(int, debug_stack_usage);
debug_stack_usage_inc(void)99 static inline void debug_stack_usage_inc(void)
100 {
101 __this_cpu_inc(debug_stack_usage);
102 }
debug_stack_usage_dec(void)103 static inline void debug_stack_usage_dec(void)
104 {
105 __this_cpu_dec(debug_stack_usage);
106 }
107 int is_debug_stack(unsigned long addr);
108 void debug_stack_set_zero(void);
109 void debug_stack_reset(void);
110 #else /* !X86_64 */
is_debug_stack(unsigned long addr)111 static inline int is_debug_stack(unsigned long addr) { return 0; }
debug_stack_set_zero(void)112 static inline void debug_stack_set_zero(void) { }
debug_stack_reset(void)113 static inline void debug_stack_reset(void) { }
debug_stack_usage_inc(void)114 static inline void debug_stack_usage_inc(void) { }
debug_stack_usage_dec(void)115 static inline void debug_stack_usage_dec(void) { }
116 #endif /* X86_64 */
117
118 #ifdef CONFIG_CPU_SUP_AMD
119 extern void set_dr_addr_mask(unsigned long mask, int dr);
120 #else
set_dr_addr_mask(unsigned long mask,int dr)121 static inline void set_dr_addr_mask(unsigned long mask, int dr) { }
122 #endif
123
124 #endif /* _ASM_X86_DEBUGREG_H */
125
