1/* SPDX-License-Identifier: GPL-2.0 */
2/* Copyright (C) B.A.T.M.A.N. contributors:
3 *
4 * Simon Wunderlich, Marek Lindner
5 */
6
7#ifndef _NET_BATMAN_ADV_BITARRAY_H_
8#define _NET_BATMAN_ADV_BITARRAY_H_
9
10#include "main.h"
11
12#include <linux/bitops.h>
13#include <linux/compiler.h>
14#include <linux/stddef.h>
15#include <linux/types.h>
16
17/**
18 * batadv_test_bit() - check if bit is set in the current window
19 *
20 * @seq_bits: pointer to the sequence number receive packet
21 * @last_seqno: latest sequence number in seq_bits
22 * @curr_seqno: sequence number to test for
23 *
24 * Return: true if the corresponding bit in the given seq_bits indicates true
25 * and curr_seqno is within range of last_seqno. Otherwise returns false.
26 */
27static inline bool batadv_test_bit(const unsigned long *seq_bits,
28				   u32 last_seqno, u32 curr_seqno)
29{
30	s32 diff;
31
32	diff = last_seqno - curr_seqno;
33	if (diff < 0 || diff >= BATADV_TQ_LOCAL_WINDOW_SIZE)
34		return false;
35	return test_bit(diff, seq_bits) != 0;
36}
37
38/**
39 * batadv_set_bit() - Turn corresponding bit on, so we can remember that we got
40 *  the packet
41 * @seq_bits: bitmap of the packet receive window
42 * @n: relative sequence number of newly received packet
43 */
44static inline void batadv_set_bit(unsigned long *seq_bits, s32 n)
45{
46	/* if too old, just drop it */
47	if (n < 0 || n >= BATADV_TQ_LOCAL_WINDOW_SIZE)
48		return;
49
50	set_bit(n, seq_bits); /* turn the position on */
51}
52
53bool batadv_bit_get_packet(void *priv, unsigned long *seq_bits,
54			   s32 seq_num_diff, int set_mark);
55
56#endif /* _NET_BATMAN_ADV_BITARRAY_H_ */
57