Commit | Line | Data |
---|---|---|
b2441318 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
1da177e4 LT |
2 | #ifndef _LINUX_FUTEX_H |
3 | #define _LINUX_FUTEX_H | |
4 | ||
2456e855 | 5 | #include <linux/ktime.h> |
607ca46e | 6 | #include <uapi/linux/futex.h> |
0771dfef | 7 | |
9064a678 MF |
8 | struct inode; |
9 | struct mm_struct; | |
10 | struct task_struct; | |
9064a678 | 11 | |
9adef58b RR |
12 | /* |
13 | * Futexes are matched on equal values of this key. | |
14 | * The key type depends on whether it's a shared or private mapping. | |
15 | * Don't rearrange members without looking at hash_futex(). | |
16 | * | |
17 | * offset is aligned to a multiple of sizeof(u32) (== 4) by definition. | |
34f01cc1 ED |
18 | * We use the two low order bits of offset to tell what is the kind of key : |
19 | * 00 : Private process futex (PTHREAD_PROCESS_PRIVATE) | |
20 | * (no reference on an inode or mm) | |
21 | * 01 : Shared futex (PTHREAD_PROCESS_SHARED) | |
22 | * mapped on a file (reference on the underlying inode) | |
23 | * 10 : Shared futex (PTHREAD_PROCESS_SHARED) | |
24 | * (but private mapping on an mm, and reference taken on it) | |
25 | */ | |
26 | ||
27 | #define FUT_OFF_INODE 1 /* We set bit 0 if key has a reference on inode */ | |
28 | #define FUT_OFF_MMSHARED 2 /* We set bit 1 if key has a reference on mm */ | |
29 | ||
9adef58b RR |
30 | union futex_key { |
31 | struct { | |
32 | unsigned long pgoff; | |
33 | struct inode *inode; | |
34 | int offset; | |
35 | } shared; | |
36 | struct { | |
37 | unsigned long address; | |
38 | struct mm_struct *mm; | |
39 | int offset; | |
40 | } private; | |
41 | struct { | |
42 | unsigned long word; | |
43 | void *ptr; | |
44 | int offset; | |
45 | } both; | |
46 | }; | |
9adef58b | 47 | |
38d47c1b PZ |
48 | #define FUTEX_KEY_INIT (union futex_key) { .both = { .ptr = NULL } } |
49 | ||
0771dfef IM |
50 | #ifdef CONFIG_FUTEX |
51 | extern void exit_robust_list(struct task_struct *curr); | |
2de0db99 DB |
52 | |
53 | long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout, | |
54 | u32 __user *uaddr2, u32 val2, u32 val3); | |
0771dfef IM |
55 | #else |
56 | static inline void exit_robust_list(struct task_struct *curr) | |
57 | { | |
58 | } | |
2de0db99 DB |
59 | |
60 | static inline long do_futex(u32 __user *uaddr, int op, u32 val, | |
61 | ktime_t *timeout, u32 __user *uaddr2, | |
62 | u32 val2, u32 val3) | |
63 | { | |
64 | return -EINVAL; | |
65 | } | |
bc2eecd7 NP |
66 | #endif |
67 | ||
68 | #ifdef CONFIG_FUTEX_PI | |
69 | extern void exit_pi_state_list(struct task_struct *curr); | |
70 | #else | |
c87e2837 IM |
71 | static inline void exit_pi_state_list(struct task_struct *curr) |
72 | { | |
73 | } | |
0771dfef | 74 | #endif |
bc2eecd7 | 75 | |
1da177e4 | 76 | #endif |