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#ifndef _UAPI_LINUX_FUTEX_H
#define _UAPI_LINUX_FUTEX_H

#include <linux/compiler.h>
#include <linux/types.h>

/* Second argument to futex syscall */


#define FUTEX_WAIT		0
#define FUTEX_WAKE		1
#define FUTEX_FD		2
#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_LOCK_PI2		13

#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_LOCK_PI2_PRIVATE	(FUTEX_LOCK_PI2 | 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)

/*
 * Flags for futex2 syscalls.
 *
 * NOTE: these are not pure flags, they can also be seen as:
 *
 *   union {
 *     u32  flags;
 *     struct {
 *       u32 size    : 2,
 *           numa    : 1,
 *                   : 4,
 *           private : 1;
 *     };
 *   };
 */
#define FUTEX2_SIZE_U8		0x00
#define FUTEX2_SIZE_U16		0x01
#define FUTEX2_SIZE_U32		0x02
#define FUTEX2_SIZE_U64		0x03
#define FUTEX2_NUMA		0x04
#define FUTEX2_MPOL		0x08
			/*	0x10 */
			/*	0x20 */
			/*	0x40 */
#define FUTEX2_PRIVATE		FUTEX_PRIVATE_FLAG

#define FUTEX2_SIZE_MASK	0x03

/* do not use */
#define FUTEX_32		FUTEX2_SIZE_U32 /* historical accident :-( */

/*
 * When FUTEX2_NUMA doubles the futex word, the second word is a node value.
 * The special value -1 indicates no-node. This is the same value as
 * NUMA_NO_NODE, except that value is not ABI, this is.
 */
#define FUTEX_NO_NODE		(-1)

/*
 * Max numbers of elements in a futex_waitv array
 */
#define FUTEX_WAITV_MAX		128

/**
 * struct futex_waitv - A waiter for vectorized wait
 * @val:	Expected value at uaddr
 * @uaddr:	User address to wait on
 * @flags:	Flags for this waiter
 * @__reserved:	Reserved member to preserve data alignment. Should be 0.
 */
struct futex_waitv {
	__u64 val;
	__u64 uaddr;
	__u32 flags;
	__u32 __reserved;
};

/*
 * Support for robust futexes: the kernel cleans up held futexes at
 * thread exit time.
 */

/*
 * Per-lock list entry - embedded in user-space locks, somewhere close
 * to the futex field. (Note: user-space uses a double-linked list to
 * achieve O(1) list add and remove, but the kernel only needs to know
 * about the forward link)
 *
 * NOTE: this structure is part of the syscall ABI, and must not be
 * changed.
 */
struct robust_list {
	struct robust_list __user *next;
};

/*
 * Per-thread list head:
 *
 * NOTE: this structure is part of the syscall ABI, and must only be
 * changed if the change is first communicated with the glibc folks.
 * (When an incompatible change is done, we'll increase the structure
 *  size, which glibc will detect)
 */
struct robust_list_head {
	/*
	 * The head of the list. Points back to itself if empty:
	 */
	struct robust_list list;

	/*
	 * This relative offset is set by user-space, it gives the kernel
	 * the relative position of the futex field to examine. This way
	 * we keep userspace flexible, to freely shape its data-structure,
	 * without hardcoding a