1 #ifndef _LINUX_HW_BREAKPOINT_H
2 #define _LINUX_HW_BREAKPOINT_H
3 
4 enum {
5 	HW_BREAKPOINT_LEN_1 = 1,
6 	HW_BREAKPOINT_LEN_2 = 2,
7 	HW_BREAKPOINT_LEN_4 = 4,
8 	HW_BREAKPOINT_LEN_8 = 8,
9 };
10 
11 enum {
12 	HW_BREAKPOINT_EMPTY	= 0,
13 	HW_BREAKPOINT_R		= 1,
14 	HW_BREAKPOINT_W		= 2,
15 	HW_BREAKPOINT_RW	= HW_BREAKPOINT_R | HW_BREAKPOINT_W,
16 	HW_BREAKPOINT_X		= 4,
17 	HW_BREAKPOINT_INVALID   = HW_BREAKPOINT_RW | HW_BREAKPOINT_X,
18 };
19 
20 enum bp_type_idx {
21 	TYPE_INST 	= 0,
22 #ifdef CONFIG_HAVE_MIXED_BREAKPOINTS_REGS
23 	TYPE_DATA	= 0,
24 #else
25 	TYPE_DATA	= 1,
26 #endif
27 	TYPE_MAX
28 };
29 
30 #ifdef __KERNEL__
31 
32 #include <linux/perf_event.h>
33 
34 #ifdef CONFIG_HAVE_HW_BREAKPOINT
35 
36 extern int __init init_hw_breakpoint(void);
37 
hw_breakpoint_init(struct perf_event_attr * attr)38 static inline void hw_breakpoint_init(struct perf_event_attr *attr)
39 {
40 	memset(attr, 0, sizeof(*attr));
41 
42 	attr->type = PERF_TYPE_BREAKPOINT;
43 	attr->size = sizeof(*attr);
44 	/*
45 	 * As it's for in-kernel or ptrace use, we want it to be pinned
46 	 * and to call its callback every hits.
47 	 */
48 	attr->pinned = 1;
49 	attr->sample_period = 1;
50 }
51 
ptrace_breakpoint_init(struct perf_event_attr * attr)52 static inline void ptrace_breakpoint_init(struct perf_event_attr *attr)
53 {
54 	hw_breakpoint_init(attr);
55 	attr->exclude_kernel = 1;
56 }
57 
hw_breakpoint_addr(struct perf_event * bp)58 static inline unsigned long hw_breakpoint_addr(struct perf_event *bp)
59 {
60 	return bp->attr.bp_addr;
61 }
62 
hw_breakpoint_type(struct perf_event * bp)63 static inline int hw_breakpoint_type(struct perf_event *bp)
64 {
65 	return bp->attr.bp_type;
66 }
67 
hw_breakpoint_len(struct perf_event * bp)68 static inline unsigned long hw_breakpoint_len(struct perf_event *bp)
69 {
70 	return bp->attr.bp_len;
71 }
72 
73 extern struct perf_event *
74 register_user_hw_breakpoint(struct perf_event_attr *attr,
75 			    perf_overflow_handler_t triggered,
76 			    struct task_struct *tsk);
77 
78 /* FIXME: only change from the attr, and don't unregister */
79 extern int
80 modify_user_hw_breakpoint(struct perf_event *bp, struct perf_event_attr *attr);
81 
82 /*
83  * Kernel breakpoints are not associated with any particular thread.
84  */
85 extern struct perf_event *
86 register_wide_hw_breakpoint_cpu(struct perf_event_attr *attr,
87 				perf_overflow_handler_t	triggered,
88 				int cpu);
89 
90 extern struct perf_event * __percpu *
91 register_wide_hw_breakpoint(struct perf_event_attr *attr,
92 			    perf_overflow_handler_t triggered);
93 
94 extern int register_perf_hw_breakpoint(struct perf_event *bp);
95 extern int __register_perf_hw_breakpoint(struct perf_event *bp);
96 extern void unregister_hw_breakpoint(struct perf_event *bp);
97 extern void unregister_wide_hw_breakpoint(struct perf_event * __percpu *cpu_events);
98 
99 extern int dbg_reserve_bp_slot(struct perf_event *bp);
100 extern int dbg_release_bp_slot(struct perf_event *bp);
101 extern int reserve_bp_slot(struct perf_event *bp);
102 extern void release_bp_slot(struct perf_event *bp);
103 
104 extern void flush_ptrace_hw_breakpoint(struct task_struct *tsk);
105 
counter_arch_bp(struct perf_event * bp)106 static inline struct arch_hw_breakpoint *counter_arch_bp(struct perf_event *bp)
107 {
108 	return &bp->hw.info;
109 }
110 
111 #else /* !CONFIG_HAVE_HW_BREAKPOINT */
112 
init_hw_breakpoint(void)113 static inline int __init init_hw_breakpoint(void) { return 0; }
114 
115 static inline struct perf_event *
register_user_hw_breakpoint(struct perf_event_attr * attr,perf_overflow_handler_t triggered,struct task_struct * tsk)116 register_user_hw_breakpoint(struct perf_event_attr *attr,
117 			    perf_overflow_handler_t triggered,
118 			    struct task_struct *tsk)	{ return NULL; }
119 static inline int
modify_user_hw_breakpoint(struct perf_event * bp,struct perf_event_attr * attr)120 modify_user_hw_breakpoint(struct perf_event *bp,
121 			  struct perf_event_attr *attr)	{ return -ENOSYS; }
122 static inline struct perf_event *
register_wide_hw_breakpoint_cpu(struct perf_event_attr * attr,perf_overflow_handler_t triggered,int cpu)123 register_wide_hw_breakpoint_cpu(struct perf_event_attr *attr,
124 				perf_overflow_handler_t	 triggered,
125 				int cpu)		{ return NULL; }
126 static inline struct perf_event * __percpu *
register_wide_hw_breakpoint(struct perf_event_attr * attr,perf_overflow_handler_t triggered)127 register_wide_hw_breakpoint(struct perf_event_attr *attr,
128 			    perf_overflow_handler_t triggered)	{ return NULL; }
129 static inline int
register_perf_hw_breakpoint(struct perf_event * bp)130 register_perf_hw_breakpoint(struct perf_event *bp)	{ return -ENOSYS; }
131 static inline int
__register_perf_hw_breakpoint(struct perf_event * bp)132 __register_perf_hw_breakpoint(struct perf_event *bp) 	{ return -ENOSYS; }
unregister_hw_breakpoint(struct perf_event * bp)133 static inline void unregister_hw_breakpoint(struct perf_event *bp)	{ }
134 static inline void
unregister_wide_hw_breakpoint(struct perf_event * __percpu * cpu_events)135 unregister_wide_hw_breakpoint(struct perf_event * __percpu *cpu_events)	{ }
136 static inline int
reserve_bp_slot(struct perf_event * bp)137 reserve_bp_slot(struct perf_event *bp)			{return -ENOSYS; }
release_bp_slot(struct perf_event * bp)138 static inline void release_bp_slot(struct perf_event *bp) 		{ }
139 
flush_ptrace_hw_breakpoint(struct task_struct * tsk)140 static inline void flush_ptrace_hw_breakpoint(struct task_struct *tsk)	{ }
141 
counter_arch_bp(struct perf_event * bp)142 static inline struct arch_hw_breakpoint *counter_arch_bp(struct perf_event *bp)
143 {
144 	return NULL;
145 }
146 
147 #endif /* CONFIG_HAVE_HW_BREAKPOINT */
148 #endif /* __KERNEL__ */
149 
150 #endif /* _LINUX_HW_BREAKPOINT_H */
151