1 #ifndef _LINUX_REFCOUNT_H 2 #define _LINUX_REFCOUNT_H 3 4 #include <linux/atomic.h> 5 #include <linux/mutex.h> 6 #include <linux/spinlock.h> 7 #include <linux/kernel.h> 8 9 typedef struct refcount_struct { 10 atomic_t refs; 11 } refcount_t; 12 13 #define REFCOUNT_INIT(n) { .refs = ATOMIC_INIT(n), } 14 15 static inline void refcount_set(refcount_t *r, unsigned int n) 16 { 17 atomic_set(&r->refs, n); 18 } 19 20 static inline unsigned int refcount_read(const refcount_t *r) 21 { 22 return atomic_read(&r->refs); 23 } 24 25 extern __must_check bool refcount_add_not_zero(unsigned int i, refcount_t *r); 26 extern void refcount_add(unsigned int i, refcount_t *r); 27 28 extern __must_check bool refcount_inc_not_zero(refcount_t *r); 29 extern void refcount_inc(refcount_t *r); 30 31 extern __must_check bool refcount_sub_and_test(unsigned int i, refcount_t *r); 32 extern void refcount_sub(unsigned int i, refcount_t *r); 33 34 extern __must_check bool refcount_dec_and_test(refcount_t *r); 35 extern void refcount_dec(refcount_t *r); 36 37 extern __must_check bool refcount_dec_if_one(refcount_t *r); 38 extern __must_check bool refcount_dec_not_one(refcount_t *r); 39 extern __must_check bool refcount_dec_and_mutex_lock(refcount_t *r, struct mutex *lock); 40 extern __must_check bool refcount_dec_and_lock(refcount_t *r, spinlock_t *lock); 41 42 #endif /* _LINUX_REFCOUNT_H */ 43