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-rw-r--r--include/linux/futex.h42
1 files changed, 37 insertions, 5 deletions
diff --git a/include/linux/futex.h b/include/linux/futex.h
index 820125c628c1..899fc7f20edd 100644
--- a/include/linux/futex.h
+++ b/include/linux/futex.h
@@ -3,6 +3,8 @@
3 3
4#include <linux/sched.h> 4#include <linux/sched.h>
5 5
6union ktime;
7
6/* Second argument to futex syscall */ 8/* Second argument to futex syscall */
7 9
8 10
@@ -15,6 +17,19 @@
15#define FUTEX_LOCK_PI 6 17#define FUTEX_LOCK_PI 6
16#define FUTEX_UNLOCK_PI 7 18#define FUTEX_UNLOCK_PI 7
17#define FUTEX_TRYLOCK_PI 8 19#define FUTEX_TRYLOCK_PI 8
20#define FUTEX_CMP_REQUEUE_PI 9
21
22#define FUTEX_PRIVATE_FLAG 128
23#define FUTEX_CMD_MASK ~FUTEX_PRIVATE_FLAG
24
25#define FUTEX_WAIT_PRIVATE (FUTEX_WAIT | FUTEX_PRIVATE_FLAG)
26#define FUTEX_WAKE_PRIVATE (FUTEX_WAKE | FUTEX_PRIVATE_FLAG)
27#define FUTEX_REQUEUE_PRIVATE (FUTEX_REQUEUE | FUTEX_PRIVATE_FLAG)
28#define FUTEX_CMP_REQUEUE_PRIVATE (FUTEX_CMP_REQUEUE | FUTEX_PRIVATE_FLAG)
29#define FUTEX_WAKE_OP_PRIVATE (FUTEX_WAKE_OP | FUTEX_PRIVATE_FLAG)
30#define FUTEX_LOCK_PI_PRIVATE (FUTEX_LOCK_PI | FUTEX_PRIVATE_FLAG)
31#define FUTEX_UNLOCK_PI_PRIVATE (FUTEX_UNLOCK_PI | FUTEX_PRIVATE_FLAG)
32#define FUTEX_TRYLOCK_PI_PRIVATE (FUTEX_TRYLOCK_PI | FUTEX_PRIVATE_FLAG)
18 33
19/* 34/*
20 * Support for robust futexes: the kernel cleans up held futexes at 35 * Support for robust futexes: the kernel cleans up held futexes at
@@ -83,9 +98,14 @@ struct robust_list_head {
83#define FUTEX_OWNER_DIED 0x40000000 98#define FUTEX_OWNER_DIED 0x40000000
84 99
85/* 100/*
101 * Some processes have been requeued on this PI-futex
102 */
103#define FUTEX_WAITER_REQUEUED 0x20000000
104
105/*
86 * The rest of the robust-futex field is for the TID: 106 * The rest of the robust-futex field is for the TID:
87 */ 107 */
88#define FUTEX_TID_MASK 0x3fffffff 108#define FUTEX_TID_MASK 0x0fffffff
89 109
90/* 110/*
91 * This limit protects against a deliberately circular list. 111 * This limit protects against a deliberately circular list.
@@ -94,7 +114,7 @@ struct robust_list_head {
94#define ROBUST_LIST_LIMIT 2048 114#define ROBUST_LIST_LIMIT 2048
95 115
96#ifdef __KERNEL__ 116#ifdef __KERNEL__
97long do_futex(u32 __user *uaddr, int op, u32 val, unsigned long timeout, 117long do_futex(u32 __user *uaddr, int op, u32 val, union ktime *timeout,
98 u32 __user *uaddr2, u32 val2, u32 val3); 118 u32 __user *uaddr2, u32 val2, u32 val3);
99 119
100extern int 120extern int
@@ -106,9 +126,20 @@ handle_futex_death(u32 __user *uaddr, struct task_struct *curr, int pi);
106 * Don't rearrange members without looking at hash_futex(). 126 * Don't rearrange members without looking at hash_futex().
107 * 127 *
108 * offset is aligned to a multiple of sizeof(u32) (== 4) by definition. 128 * offset is aligned to a multiple of sizeof(u32) (== 4) by definition.
109 * We set bit 0 to indicate if it's an inode-based key. 129 * We use the two low order bits of offset to tell what is the kind of key :
110 */ 130 * 00 : Private process futex (PTHREAD_PROCESS_PRIVATE)
131 * (no reference on an inode or mm)
132 * 01 : Shared futex (PTHREAD_PROCESS_SHARED)
133 * mapped on a file (reference on the underlying inode)
134 * 10 : Shared futex (PTHREAD_PROCESS_SHARED)
135 * (but private mapping on an mm, and reference taken on it)
136*/
137
138#define FUT_OFF_INODE 1 /* We set bit 0 if key has a reference on inode */
139#define FUT_OFF_MMSHARED 2 /* We set bit 1 if key has a reference on mm */
140
111union futex_key { 141union futex_key {
142 u32 __user *uaddr;
112 struct { 143 struct {
113 unsigned long pgoff; 144 unsigned long pgoff;
114 struct inode *inode; 145 struct inode *inode;
@@ -125,7 +156,8 @@ union futex_key {
125 int offset; 156 int offset;
126 } both; 157 } both;
127}; 158};
128int get_futex_key(u32 __user *uaddr, union futex_key *key); 159int get_futex_key(u32 __user *uaddr, struct rw_semaphore *shared,
160 union futex_key *key);
129void get_futex_key_refs(union futex_key *key); 161void get_futex_key_refs(union futex_key *key);
130void drop_futex_key_refs(union futex_key *key); 162void drop_futex_key_refs(union futex_key *key);
131 163