4 #include <linux/sched.h>
6 #include <uapi/linux/futex.h>
13 long do_futex(u32 __user *uaddr, int op, u32 val, union ktime *timeout,
14 u32 __user *uaddr2, u32 val2, u32 val3);
17 * Futexes are matched on equal values of this key.
18 * The key type depends on whether it's a shared or private mapping.
19 * Don't rearrange members without looking at hash_futex().
21 * offset is aligned to a multiple of sizeof(u32) (== 4) by definition.
22 * We use the two low order bits of offset to tell what is the kind of key :
23 * 00 : Private process futex (PTHREAD_PROCESS_PRIVATE)
24 * (no reference on an inode or mm)
25 * 01 : Shared futex (PTHREAD_PROCESS_SHARED)
26 * mapped on a file (reference on the underlying inode)
27 * 10 : Shared futex (PTHREAD_PROCESS_SHARED)
28 * (but private mapping on an mm, and reference taken on it)
31 #define FUT_OFF_INODE 1 /* We set bit 0 if key has a reference on inode */
32 #define FUT_OFF_MMSHARED 2 /* We set bit 1 if key has a reference on mm */
45 unsigned long address;
55 #define FUTEX_KEY_INIT (union futex_key) { .both = { .ptr = 0ULL } }
64 static inline void futex_init_task(struct task_struct *tsk)
66 tsk->robust_list = NULL;
68 tsk->compat_robust_list = NULL;
70 INIT_LIST_HEAD(&tsk->pi_state_list);
71 tsk->pi_state_cache = NULL;
72 tsk->futex_state = FUTEX_STATE_OK;
73 mutex_init(&tsk->futex_exit_mutex);
76 void futex_exit_recursive(struct task_struct *tsk);
77 void futex_exit_release(struct task_struct *tsk);
78 void futex_exec_release(struct task_struct *tsk);
80 long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout,
81 u32 __user *uaddr2, u32 val2, u32 val3);
83 static inline void futex_init_task(struct task_struct *tsk) { }
84 static inline void futex_exit_recursive(struct task_struct *tsk) { }
85 static inline void futex_exit_release(struct task_struct *tsk) { }
86 static inline void futex_exec_release(struct task_struct *tsk) { }