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
14 DECLARE_TRACEPOINT(mmap_lock_start_locking);
15 DECLARE_TRACEPOINT(mmap_lock_acquire_returned);
16 DECLARE_TRACEPOINT(mmap_lock_released);
17
18 #ifdef CONFIG_TRACING
19
20 void __mmap_lock_do_trace_start_locking(struct mm_struct *mm, bool write);
21 void __mmap_lock_do_trace_acquire_returned(struct mm_struct *mm, bool write,
22 bool success);
23 void __mmap_lock_do_trace_released(struct mm_struct *mm, bool write);
24
__mmap_lock_trace_start_locking(struct mm_struct * mm,bool write)25 static 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
__mmap_lock_trace_acquire_returned(struct mm_struct * mm,bool write,bool success)32 static 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
__mmap_lock_trace_released(struct mm_struct * mm,bool write)39 static 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
__mmap_lock_trace_start_locking(struct mm_struct * mm,bool write)47 static inline void __mmap_lock_trace_start_locking(struct mm_struct *mm,
48 bool write)
49 {
50 }
51
__mmap_lock_trace_acquire_returned(struct mm_struct * mm,bool write,bool success)52 static inline void __mmap_lock_trace_acquire_returned(struct mm_struct *mm,
53 bool write, bool success)
54 {
55 }
56
__mmap_lock_trace_released(struct mm_struct * mm,bool write)57 static inline void __mmap_lock_trace_released(struct mm_struct *mm, bool write)
58 {
59 }
60
61 #endif /* CONFIG_TRACING */
62
mmap_init_lock(struct mm_struct * mm)63 static inline void mmap_init_lock(struct mm_struct *mm)
64 {
65 init_rwsem(&mm->mmap_lock);
66 }
67
mmap_write_lock(struct mm_struct * mm)68 static 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
mmap_write_lock_nested(struct mm_struct * mm,int subclass)75 static 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
mmap_write_lock_killable(struct mm_struct * mm)82 static 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
mmap_write_trylock(struct mm_struct * mm)92 static 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
mmap_write_unlock(struct mm_struct * mm)102 static inline void mmap_write_unlock(struct mm_struct *mm)
103 {
104 up_write(&mm->mmap_lock);
105 __mmap_lock_trace_released(mm, true);
106 }
107
mmap_write_downgrade(struct mm_struct * mm)108 static inline void mmap_write_downgrade(struct mm_struct *mm)
109 {
110 downgrade_write(&mm->mmap_lock);
111 __mmap_lock_trace_acquire_returned(mm, false, true);
112 }
113
mmap_read_lock(struct mm_struct * mm)114 static 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
mmap_read_lock_killable(struct mm_struct * mm)121 static 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
mmap_read_trylock(struct mm_struct * mm)131 static 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
mmap_read_unlock(struct mm_struct * mm)141 static inline void mmap_read_unlock(struct mm_struct *mm)
142 {
143 up_read(&mm->mmap_lock);
144 __mmap_lock_trace_released(mm, false);
145 }
146
mmap_read_trylock_non_owner(struct mm_struct * mm)147 static inline bool mmap_read_trylock_non_owner(struct mm_struct *mm)
148 {
149 if (mmap_read_trylock(mm)) {
150 rwsem_release(&mm->mmap_lock.dep_map, _RET_IP_);
151 return true;
152 }
153 return false;
154 }
155
mmap_read_unlock_non_owner(struct mm_struct * mm)156 static inline void mmap_read_unlock_non_owner(struct mm_struct *mm)
157 {
158 up_read_non_owner(&mm->mmap_lock);
159 __mmap_lock_trace_released(mm, false);
160 }
161
mmap_assert_locked(struct mm_struct * mm)162 static inline void mmap_assert_locked(struct mm_struct *mm)
163 {
164 lockdep_assert_held(&mm->mmap_lock);
165 VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm);
166 }
167
mmap_assert_write_locked(struct mm_struct * mm)168 static inline void mmap_assert_write_locked(struct mm_struct *mm)
169 {
170 lockdep_assert_held_write(&mm->mmap_lock);
171 VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm);
172 }
173
mmap_lock_is_contended(struct mm_struct * mm)174 static inline int mmap_lock_is_contended(struct mm_struct *mm)
175 {
176 return rwsem_is_contended(&mm->mmap_lock);
177 }
178
179 #endif /* _LINUX_MMAP_LOCK_H */
180