1#ifndef _LINUX_MMAP_LOCK_H
2#define _LINUX_MMAP_LOCK_H
3
4#include <linux/lockdep.h>
5#include <linux/mm_types.h>
6#include <linux/mmdebug.h>
7#include <linux/rwsem.h>
8#include <linux/tracepoint-defs.h>
9#include <linux/types.h>
10
11#define MMAP_LOCK_INITIALIZER(name) \
12 .mmap_lock = __RWSEM_INITIALIZER((name).mmap_lock),
13
14DECLARE_TRACEPOINT(mmap_lock_start_locking);
15DECLARE_TRACEPOINT(mmap_lock_acquire_returned);
16DECLARE_TRACEPOINT(mmap_lock_released);
17
18#ifdef CONFIG_TRACING
19
20void __mmap_lock_do_trace_start_locking(struct mm_struct *mm, bool write);
21void __mmap_lock_do_trace_acquire_returned(struct mm_struct *mm, bool write,
22 bool success);
23void __mmap_lock_do_trace_released(struct mm_struct *mm, bool write);
24
25static inline void __mmap_lock_trace_start_locking(struct mm_struct *mm,
26 bool write)
27{
28 if (tracepoint_enabled(mmap_lock_start_locking))
29 __mmap_lock_do_trace_start_locking(mm, write);
30}
31
32static inline void __mmap_lock_trace_acquire_returned(struct mm_struct *mm,
33 bool write, bool success)
34{
35 if (tracepoint_enabled(mmap_lock_acquire_returned))
36 __mmap_lock_do_trace_acquire_returned(mm, write, success);
37}
38
39static inline void __mmap_lock_trace_released(struct mm_struct *mm, bool write)
40{
41 if (tracepoint_enabled(mmap_lock_released))
42 __mmap_lock_do_trace_released(mm, write);
43}
44
45#else /* !CONFIG_TRACING */
46
47static inline void __mmap_lock_trace_start_locking(struct mm_struct *mm,
48 bool write)
49{
50}
51
52static inline void __mmap_lock_trace_acquire_returned(struct mm_struct *mm,
53 bool write, bool success)
54{
55}
56
57static inline void __mmap_lock_trace_released(struct mm_struct *mm, bool write)
58{
59}
60
61#endif /* CONFIG_TRACING */
62
63static inline void mmap_init_lock(struct mm_struct *mm)
64{
65 init_rwsem(&mm->mmap_lock);
66}
67
68static inline void mmap_write_lock(struct mm_struct *mm)
69{
70 __mmap_lock_trace_start_locking(mm, true);
71 down_write(&mm->mmap_lock);
72 __mmap_lock_trace_acquire_returned(mm, true, true);
73}
74
75static inline void mmap_write_lock_nested(struct mm_struct *mm, int subclass)
76{
77 __mmap_lock_trace_start_locking(mm, true);
78 down_write_nested(&mm->mmap_lock, subclass);
79 __mmap_lock_trace_acquire_returned(mm, true, true);
80}
81
82static inline int mmap_write_lock_killable(struct mm_struct *mm)
83{
84 int ret;
85
86 __mmap_lock_trace_start_locking(mm, true);
87 ret = down_write_killable(&mm->mmap_lock);
88 __mmap_lock_trace_acquire_returned(mm, true, ret == 0);
89 return ret;
90}
91
92static inline bool mmap_write_trylock(struct mm_struct *mm)
93{
94 bool ret;
95
96 __mmap_lock_trace_start_locking(mm, true);
97 ret = down_write_trylock(&mm->mmap_lock) != 0;
98 __mmap_lock_trace_acquire_returned(mm, true, ret);
99 return ret;
100}
101
102static inline void mmap_write_unlock(struct mm_struct *mm)
103{
104 __mmap_lock_trace_released(mm, true);
105 up_write(&mm->mmap_lock);
106}
107
108static inline void mmap_write_downgrade(struct mm_struct *mm)
109{
110 __mmap_lock_trace_acquire_returned(mm, false, true);
111 downgrade_write(&mm->mmap_lock);
112}
113
114static inline void mmap_read_lock(struct mm_struct *mm)
115{
116 __mmap_lock_trace_start_locking(mm, false);
117 down_read(&mm->mmap_lock);
118 __mmap_lock_trace_acquire_returned(mm, false, true);
119}
120
121static inline int mmap_read_lock_killable(struct mm_struct *mm)
122{
123 int ret;
124
125 __mmap_lock_trace_start_locking(mm, false);
126 ret = down_read_killable(&mm->mmap_lock);
127 __mmap_lock_trace_acquire_returned(mm, false, ret == 0);
128 return ret;
129}
130
131static inline bool mmap_read_trylock(struct mm_struct *mm)
132{
133 bool ret;
134
135 __mmap_lock_trace_start_locking(mm, false);
136 ret = down_read_trylock(&mm->mmap_lock) != 0;
137 __mmap_lock_trace_acquire_returned(mm, false, ret);
138 return ret;
139}
140
141static inline void mmap_read_unlock(struct mm_struct *mm)
142{
143 __mmap_lock_trace_released(mm, false);
144 up_read(&mm->mmap_lock);
145}
146
147static inline void mmap_read_unlock_non_owner(struct mm_struct *mm)
148{
149 __mmap_lock_trace_released(mm, false);
150 up_read_non_owner(&mm->mmap_lock);
151}
152
153static inline void mmap_assert_locked(struct mm_struct *mm)
154{
155 lockdep_assert_held(&mm->mmap_lock);
156 VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm);
157}
158
159static inline void mmap_assert_write_locked(struct mm_struct *mm)
160{
161 lockdep_assert_held_write(&mm->mmap_lock);
162 VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm);
163}
164
165static inline int mmap_lock_is_contended(struct mm_struct *mm)
166{
167 return rwsem_is_contended(&mm->mmap_lock);
168}
169
170#endif /* _LINUX_MMAP_LOCK_H */
171

source code of linux/include/linux/mmap_lock.h