1 #ifndef _LINUX_MMAP_LOCK_H
2 #define _LINUX_MMAP_LOCK_H
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>
11 #define MMAP_LOCK_INITIALIZER(name) \
12 .mmap_lock = __RWSEM_INITIALIZER((name).mmap_lock),
14 DECLARE_TRACEPOINT(mmap_lock_start_locking);
15 DECLARE_TRACEPOINT(mmap_lock_acquire_returned);
16 DECLARE_TRACEPOINT(mmap_lock_released);
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,
23 void __mmap_lock_do_trace_released(struct mm_struct *mm, bool write);
25 static inline void __mmap_lock_trace_start_locking(struct mm_struct *mm,
28 if (tracepoint_enabled(mmap_lock_start_locking))
29 __mmap_lock_do_trace_start_locking(mm, write);
32 static inline void __mmap_lock_trace_acquire_returned(struct mm_struct *mm,
33 bool write, bool success)
35 if (tracepoint_enabled(mmap_lock_acquire_returned))
36 __mmap_lock_do_trace_acquire_returned(mm, write, success);
39 static inline void __mmap_lock_trace_released(struct mm_struct *mm, bool write)
41 if (tracepoint_enabled(mmap_lock_released))
42 __mmap_lock_do_trace_released(mm, write);
45 #else /* !CONFIG_TRACING */
47 static inline void __mmap_lock_trace_start_locking(struct mm_struct *mm,
52 static inline void __mmap_lock_trace_acquire_returned(struct mm_struct *mm,
53 bool write, bool success)
57 static inline void __mmap_lock_trace_released(struct mm_struct *mm, bool write)
61 #endif /* CONFIG_TRACING */
63 static inline void mmap_assert_locked(struct mm_struct *mm)
65 lockdep_assert_held(&mm->mmap_lock);
66 VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm);
69 static inline void mmap_assert_write_locked(struct mm_struct *mm)
71 lockdep_assert_held_write(&mm->mmap_lock);
72 VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm);
75 #ifdef CONFIG_PER_VMA_LOCK
76 static inline void vma_end_write_all(struct mm_struct *mm)
78 mmap_assert_write_locked(mm);
79 /* No races during update due to exclusive mmap_lock being held */
80 WRITE_ONCE(mm->mm_lock_seq, mm->mm_lock_seq + 1);
83 static inline void vma_end_write_all(struct mm_struct *mm) {}
86 static inline void mmap_init_lock(struct mm_struct *mm)
88 init_rwsem(&mm->mmap_lock);
91 static inline void mmap_write_lock(struct mm_struct *mm)
93 __mmap_lock_trace_start_locking(mm, true);
94 down_write(&mm->mmap_lock);
95 __mmap_lock_trace_acquire_returned(mm, true, true);
98 static inline void mmap_write_lock_nested(struct mm_struct *mm, int subclass)
100 __mmap_lock_trace_start_locking(mm, true);
101 down_write_nested(&mm->mmap_lock, subclass);
102 __mmap_lock_trace_acquire_returned(mm, true, true);
105 static inline int mmap_write_lock_killable(struct mm_struct *mm)
109 __mmap_lock_trace_start_locking(mm, true);
110 ret = down_write_killable(&mm->mmap_lock);
111 __mmap_lock_trace_acquire_returned(mm, true, ret == 0);
115 static inline bool mmap_write_trylock(struct mm_struct *mm)
119 __mmap_lock_trace_start_locking(mm, true);
120 ret = down_write_trylock(&mm->mmap_lock) != 0;
121 __mmap_lock_trace_acquire_returned(mm, true, ret);
125 static inline void mmap_write_unlock(struct mm_struct *mm)
127 __mmap_lock_trace_released(mm, true);
128 vma_end_write_all(mm);
129 up_write(&mm->mmap_lock);
132 static inline void mmap_write_downgrade(struct mm_struct *mm)
134 __mmap_lock_trace_acquire_returned(mm, false, true);
135 vma_end_write_all(mm);
136 downgrade_write(&mm->mmap_lock);
139 static inline void mmap_read_lock(struct mm_struct *mm)
141 __mmap_lock_trace_start_locking(mm, false);
142 down_read(&mm->mmap_lock);
143 __mmap_lock_trace_acquire_returned(mm, false, true);
146 static inline int mmap_read_lock_killable(struct mm_struct *mm)
150 __mmap_lock_trace_start_locking(mm, false);
151 ret = down_read_killable(&mm->mmap_lock);
152 __mmap_lock_trace_acquire_returned(mm, false, ret == 0);
156 static inline bool mmap_read_trylock(struct mm_struct *mm)
160 __mmap_lock_trace_start_locking(mm, false);
161 ret = down_read_trylock(&mm->mmap_lock) != 0;
162 __mmap_lock_trace_acquire_returned(mm, false, ret);
166 static inline void mmap_read_unlock(struct mm_struct *mm)
168 __mmap_lock_trace_released(mm, false);
169 up_read(&mm->mmap_lock);
172 static inline void mmap_read_unlock_non_owner(struct mm_struct *mm)
174 __mmap_lock_trace_released(mm, false);
175 up_read_non_owner(&mm->mmap_lock);
178 static inline int mmap_lock_is_contended(struct mm_struct *mm)
180 return rwsem_is_contended(&mm->mmap_lock);
183 #endif /* _LINUX_MMAP_LOCK_H */