rcu: remove all rcu head initializations, except on_stack initializations

[linux-2.6.git] / include / linux / futex.h

diff --git a/include/linux/futex.h b/include/linux/futex.h
index 20face6b798d9c9087c131d3237ad61688397f23..1e5a26d7923216e2de6883fff7c4faf6f5507036 100644 (file)
--- a/include/linux/futex.h
+++ b/include/linux/futex.h
@@ -1,7 +1,8 @@
 #ifndef _LINUX_FUTEX_H
 #define _LINUX_FUTEX_H
 
-#include <linux/sched.h>
+#include <linux/compiler.h>
+#include <linux/types.h>
 
 /* Second argument to futex syscall */
 
@@ -12,6 +13,32 @@
 #define FUTEX_REQUEUE          3
 #define FUTEX_CMP_REQUEUE      4
 #define FUTEX_WAKE_OP          5
+#define FUTEX_LOCK_PI          6
+#define FUTEX_UNLOCK_PI                7
+#define FUTEX_TRYLOCK_PI       8
+#define FUTEX_WAIT_BITSET      9
+#define FUTEX_WAKE_BITSET      10
+#define FUTEX_WAIT_REQUEUE_PI  11
+#define FUTEX_CMP_REQUEUE_PI   12
+
+#define FUTEX_PRIVATE_FLAG     128
+#define FUTEX_CLOCK_REALTIME   256
+#define FUTEX_CMD_MASK         ~(FUTEX_PRIVATE_FLAG | FUTEX_CLOCK_REALTIME)
+
+#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)
+#define FUTEX_WAIT_BITSET_PRIVATE      (FUTEX_WAIT_BITSET | FUTEX_PRIVATE_FLAG)
+#define FUTEX_WAKE_BITSET_PRIVATE      (FUTEX_WAKE_BITSET | FUTEX_PRIVATE_FLAG)
+#define FUTEX_WAIT_REQUEUE_PI_PRIVATE  (FUTEX_WAIT_REQUEUE_PI | \
+                                        FUTEX_PRIVATE_FLAG)
+#define FUTEX_CMP_REQUEUE_PI_PRIVATE   (FUTEX_CMP_REQUEUE_PI | \
+                                        FUTEX_PRIVATE_FLAG)
 
 /*
  * Support for robust futexes: the kernel cleans up held futexes at
@@ -80,35 +107,85 @@ struct robust_list_head {
 #define FUTEX_OWNER_DIED       0x40000000
 
 /*
- * Reserved bit:
+ * The rest of the robust-futex field is for the TID:
  */
-#define FUTEX_OWNER_PENDING    0x20000000
+#define FUTEX_TID_MASK         0x3fffffff
 
 /*
- * The rest of the robust-futex field is for the TID:
+ * This limit protects against a deliberately circular list.
+ * (Not worth introducing an rlimit for it)
  */
-#define FUTEX_TID_MASK         0x1fffffff
+#define ROBUST_LIST_LIMIT      2048
 
 /*
- * A limit of one million locks held per thread (!) ought to be enough
- * for some time. This also protects against a deliberately circular
- * list. Not worth introducing an rlimit for this:
+ * bitset with all bits set for the FUTEX_xxx_BITSET OPs to request a
+ * match of any bit.
  */
-#define ROBUST_LIST_LIMIT      1048576
+#define FUTEX_BITSET_MATCH_ANY 0xffffffff
+
+#ifdef __KERNEL__
+struct inode;
+struct mm_struct;
+struct task_struct;
+union ktime;
+
+long do_futex(u32 __user *uaddr, int op, u32 val, union ktime *timeout,
+             u32 __user *uaddr2, u32 val2, u32 val3);
+
+extern int
+handle_futex_death(u32 __user *uaddr, struct task_struct *curr, int pi);
 
-long do_futex(unsigned long uaddr, int op, int val,
-               unsigned long timeout, unsigned long uaddr2, int val2,
-               int val3);
+/*
+ * Futexes are matched on equal values of this key.
+ * The key type depends on whether it's a shared or private mapping.
+ * Don't rearrange members without looking at hash_futex().
+ *
+ * offset is aligned to a multiple of sizeof(u32) (== 4) by definition.
+ * 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 {
+       struct {
+               unsigned long pgoff;
+               struct inode *inode;
+               int offset;
+       } shared;
+       struct {
+               unsigned long address;
+               struct mm_struct *mm;
+               int offset;
+       } private;
+       struct {
+               unsigned long word;
+               void *ptr;
+               int offset;
+       } both;
+};
 
-extern int handle_futex_death(unsigned int *uaddr, struct task_struct *curr);
+#define FUTEX_KEY_INIT (union futex_key) { .both = { .ptr = NULL } }
 
 #ifdef CONFIG_FUTEX
 extern void exit_robust_list(struct task_struct *curr);
+extern void exit_pi_state_list(struct task_struct *curr);
+extern int futex_cmpxchg_enabled;
 #else
 static inline void exit_robust_list(struct task_struct *curr)
 {
 }
+static inline void exit_pi_state_list(struct task_struct *curr)
+{
+}
 #endif
+#endif /* __KERNEL__ */
 
 #define FUTEX_OP_SET           0       /* *(int *)UADDR2 = OPARG; */
 #define FUTEX_OP_ADD           1       /* *(int *)UADDR2 += OPARG; */