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Diffstat (limited to 'include/linux/futex.h')
-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 820125c628c..899fc7f20ed 100644
--- a/include/linux/futex.h
+++ b/include/linux/futex.h
@@ -3,6 +3,8 @@
#include <linux/sched.h>
+union ktime;
+
/* Second argument to futex syscall */
@@ -15,6 +17,19 @@
#define FUTEX_LOCK_PI 6
#define FUTEX_UNLOCK_PI 7
#define FUTEX_TRYLOCK_PI 8
+#define FUTEX_CMP_REQUEUE_PI 9
+
+#define FUTEX_PRIVATE_FLAG 128
+#define FUTEX_CMD_MASK ~FUTEX_PRIVATE_FLAG
+
+#define FUTEX_WAIT_PRIVATE (FUTEX_WAIT | FUTEX_PRIVATE_FLAG)
+#define FUTEX_WAKE_PRIVATE (FUTEX_WAKE | FUTEX_PRIVATE_FLAG)
+#define FUTEX_REQUEUE_PRIVATE (FUTEX_REQUEUE | FUTEX_PRIVATE_FLAG)
+#define FUTEX_CMP_REQUEUE_PRIVATE (FUTEX_CMP_REQUEUE | FUTEX_PRIVATE_FLAG)
+#define FUTEX_WAKE_OP_PRIVATE (FUTEX_WAKE_OP | FUTEX_PRIVATE_FLAG)
+#define FUTEX_LOCK_PI_PRIVATE (FUTEX_LOCK_PI | FUTEX_PRIVATE_FLAG)
+#define FUTEX_UNLOCK_PI_PRIVATE (FUTEX_UNLOCK_PI | FUTEX_PRIVATE_FLAG)
+#define FUTEX_TRYLOCK_PI_PRIVATE (FUTEX_TRYLOCK_PI | FUTEX_PRIVATE_FLAG)
/*
* Support for robust futexes: the kernel cleans up held futexes at
@@ -83,9 +98,14 @@ struct robust_list_head {
#define FUTEX_OWNER_DIED 0x40000000
/*
+ * Some processes have been requeued on this PI-futex
+ */
+#define FUTEX_WAITER_REQUEUED 0x20000000
+
+/*
* The rest of the robust-futex field is for the TID:
*/
-#define FUTEX_TID_MASK 0x3fffffff
+#define FUTEX_TID_MASK 0x0fffffff
/*
* This limit protects against a deliberately circular list.
@@ -94,7 +114,7 @@ struct robust_list_head {
#define ROBUST_LIST_LIMIT 2048
#ifdef __KERNEL__
-long do_futex(u32 __user *uaddr, int op, u32 val, unsigned long timeout,
+long do_futex(u32 __user *uaddr, int op, u32 val, union ktime *timeout,
u32 __user *uaddr2, u32 val2, u32 val3);
extern int
@@ -106,9 +126,20 @@ handle_futex_death(u32 __user *uaddr, struct task_struct *curr, int pi);
* Don't rearrange members without looking at hash_futex().
*
* offset is aligned to a multiple of sizeof(u32) (== 4) by definition.
- * We set bit 0 to indicate if it's an inode-based key.
- */
+ * We use the two low order bits of offset to tell what is the kind of key :
+ * 00 : Private process futex (PTHREAD_PROCESS_PRIVATE)
+ * (no reference on an inode or mm)
+ * 01 : Shared futex (PTHREAD_PROCESS_SHARED)
+ * mapped on a file (reference on the underlying inode)
+ * 10 : Shared futex (PTHREAD_PROCESS_SHARED)
+ * (but private mapping on an mm, and reference taken on it)
+*/
+
+#define FUT_OFF_INODE 1 /* We set bit 0 if key has a reference on inode */
+#define FUT_OFF_MMSHARED 2 /* We set bit 1 if key has a reference on mm */
+
union futex_key {
+ u32 __user *uaddr;
struct {
unsigned long pgoff;
struct inode *inode;
@@ -125,7 +156,8 @@ union futex_key {
int offset;
} both;
};
-int get_futex_key(u32 __user *uaddr, union futex_key *key);
+int get_futex_key(u32 __user *uaddr, struct rw_semaphore *shared,
+ union futex_key *key);
void get_futex_key_refs(union futex_key *key);
void drop_futex_key_refs(union futex_key *key);