1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_HW_BREAKPOINT_H
3#define _LINUX_HW_BREAKPOINT_H
4
5#include <linux/perf_event.h>
6#include <uapi/linux/hw_breakpoint.h>
7
8#ifdef CONFIG_HAVE_HW_BREAKPOINT
9
10enum bp_type_idx {
11 TYPE_INST = 0,
12#if defined(CONFIG_HAVE_MIXED_BREAKPOINTS_REGS)
13 TYPE_DATA = 0,
14#else
15 TYPE_DATA = 1,
16#endif
17 TYPE_MAX
18};
19
20extern int __init init_hw_breakpoint(void);
21
22static inline void hw_breakpoint_init(struct perf_event_attr *attr)
23{
24 memset(s: attr, c: 0, n: sizeof(*attr));
25
26 attr->type = PERF_TYPE_BREAKPOINT;
27 attr->size = sizeof(*attr);
28 /*
29 * As it's for in-kernel or ptrace use, we want it to be pinned
30 * and to call its callback every hits.
31 */
32 attr->pinned = 1;
33 attr->sample_period = 1;
34}
35
36static inline void ptrace_breakpoint_init(struct perf_event_attr *attr)
37{
38 hw_breakpoint_init(attr);
39 attr->exclude_kernel = 1;
40}
41
42static inline unsigned long hw_breakpoint_addr(struct perf_event *bp)
43{
44 return bp->attr.bp_addr;
45}
46
47static inline int hw_breakpoint_type(struct perf_event *bp)
48{
49 return bp->attr.bp_type;
50}
51
52static inline unsigned long hw_breakpoint_len(struct perf_event *bp)
53{
54 return bp->attr.bp_len;
55}
56
57extern struct perf_event *
58register_user_hw_breakpoint(struct perf_event_attr *attr,
59 perf_overflow_handler_t triggered,
60 void *context,
61 struct task_struct *tsk);
62
63/* FIXME: only change from the attr, and don't unregister */
64extern int
65modify_user_hw_breakpoint(struct perf_event *bp, struct perf_event_attr *attr);
66extern int
67modify_user_hw_breakpoint_check(struct perf_event *bp, struct perf_event_attr *attr,
68 bool check);
69
70/*
71 * Kernel breakpoints are not associated with any particular thread.
72 */
73extern struct perf_event *
74register_wide_hw_breakpoint_cpu(struct perf_event_attr *attr,
75 perf_overflow_handler_t triggered,
76 void *context,
77 int cpu);
78
79extern struct perf_event * __percpu *
80register_wide_hw_breakpoint(struct perf_event_attr *attr,
81 perf_overflow_handler_t triggered,
82 void *context);
83
84extern int register_perf_hw_breakpoint(struct perf_event *bp);
85extern void unregister_hw_breakpoint(struct perf_event *bp);
86extern void unregister_wide_hw_breakpoint(struct perf_event * __percpu *cpu_events);
87extern bool hw_breakpoint_is_used(void);
88
89extern int dbg_reserve_bp_slot(struct perf_event *bp);
90extern int dbg_release_bp_slot(struct perf_event *bp);
91extern int reserve_bp_slot(struct perf_event *bp);
92extern void release_bp_slot(struct perf_event *bp);
93
94extern void flush_ptrace_hw_breakpoint(struct task_struct *tsk);
95
96static inline struct arch_hw_breakpoint *counter_arch_bp(struct perf_event *bp)
97{
98 return &bp->hw.info;
99}
100
101#else /* !CONFIG_HAVE_HW_BREAKPOINT */
102
103static inline int __init init_hw_breakpoint(void) { return 0; }
104
105static inline struct perf_event *
106register_user_hw_breakpoint(struct perf_event_attr *attr,
107 perf_overflow_handler_t triggered,
108 void *context,
109 struct task_struct *tsk) { return NULL; }
110static inline int
111modify_user_hw_breakpoint(struct perf_event *bp,
112 struct perf_event_attr *attr) { return -ENOSYS; }
113static inline int
114modify_user_hw_breakpoint_check(struct perf_event *bp, struct perf_event_attr *attr,
115 bool check) { return -ENOSYS; }
116
117static inline struct perf_event *
118register_wide_hw_breakpoint_cpu(struct perf_event_attr *attr,
119 perf_overflow_handler_t triggered,
120 void *context,
121 int cpu) { return NULL; }
122static inline struct perf_event * __percpu *
123register_wide_hw_breakpoint(struct perf_event_attr *attr,
124 perf_overflow_handler_t triggered,
125 void *context) { return NULL; }
126static inline int
127register_perf_hw_breakpoint(struct perf_event *bp) { return -ENOSYS; }
128static inline void unregister_hw_breakpoint(struct perf_event *bp) { }
129static inline void
130unregister_wide_hw_breakpoint(struct perf_event * __percpu *cpu_events) { }
131static inline bool hw_breakpoint_is_used(void) { return false; }
132
133static inline int
134reserve_bp_slot(struct perf_event *bp) {return -ENOSYS; }
135static inline void release_bp_slot(struct perf_event *bp) { }
136
137static inline void flush_ptrace_hw_breakpoint(struct task_struct *tsk) { }
138
139static inline struct arch_hw_breakpoint *counter_arch_bp(struct perf_event *bp)
140{
141 return NULL;
142}
143
144#endif /* CONFIG_HAVE_HW_BREAKPOINT */
145#endif /* _LINUX_HW_BREAKPOINT_H */
146