1 files changed, 71 insertions, 0 deletions
diff --git a/kernel/include/linux/futex.h b/kernel/include/linux/futex.h
new file mode 100644
index 000000000..6435f46d6
--- /dev/null
+++ b/kernel/include/linux/futex.h
@@ -0,0 +1,71 @@
+#ifndef _LINUX_FUTEX_H
+#define _LINUX_FUTEX_H
+
+#include <uapi/linux/futex.h>
+
+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);
+
+/*
+ * 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;
+};
+
+#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);
+#ifdef CONFIG_HAVE_FUTEX_CMPXCHG
+#define futex_cmpxchg_enabled 1
+#else
+extern int futex_cmpxchg_enabled;
+#endif
+#else
+static inline void exit_robust_list(struct task_struct *curr)
+{
+}
+static inline void exit_pi_state_list(struct task_struct *curr)
+{
+}
+#endif
+#endif