[mirror_ubuntu-bionic-kernel.git] / net / batman-adv / bitarray.h

/* Copyright (C) 2006-2017  B.A.T.M.A.N. contributors:
 *
 * Simon Wunderlich, Marek Lindner
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see <http://www.gnu.org/licenses/>.
 */

#ifndef _NET_BATMAN_ADV_BITARRAY_H_
#define _NET_BATMAN_ADV_BITARRAY_H_

#include "main.h"

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

/**
 * batadv_test_bit - check if bit is set in the current window
 *
 * @seq_bits: pointer to the sequence number receive packet
 * @last_seqno: latest sequence number in seq_bits
 * @curr_seqno: sequence number to test for
 *
 * Return: true if the corresponding bit in the given seq_bits indicates true
 * and curr_seqno is within range of last_seqno. Otherwise returns false.
 */
static inline bool batadv_test_bit(const unsigned long *seq_bits,
				   u32 last_seqno, u32 curr_seqno)
{
	s32 diff;

	diff = last_seqno - curr_seqno;
	if (diff < 0 || diff >= BATADV_TQ_LOCAL_WINDOW_SIZE)
		return false;
	return test_bit(diff, seq_bits) != 0;
}

/* turn corresponding bit on, so we can remember that we got the packet */
static inline void batadv_set_bit(unsigned long *seq_bits, s32 n)
{
	/* if too old, just drop it */
	if (n < 0 || n >= BATADV_TQ_LOCAL_WINDOW_SIZE)
		return;

	set_bit(n, seq_bits); /* turn the position on */
}

bool batadv_bit_get_packet(void *priv, unsigned long *seq_bits,
			   s32 seq_num_diff, int set_mark);

#endif /* _NET_BATMAN_ADV_BITARRAY_H_ */
Commit	Line	Data
ac79cbb9	1	/* Copyright (C) 2006-2017 B.A.T.M.A.N. contributors:
c6c8fea2 SE	2	*
	3	* Simon Wunderlich, Marek Lindner
	4	*
	5	* This program is free software; you can redistribute it and/or
	6	* modify it under the terms of version 2 of the GNU General Public
	7	* License as published by the Free Software Foundation.
	8	*
	9	* This program is distributed in the hope that it will be useful, but
	10	* WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	12	* General Public License for more details.
	13	*
	14	* You should have received a copy of the GNU General Public License
ebf38fb7	15	* along with this program; if not, see <http://www.gnu.org/licenses/>.
c6c8fea2 SE	16	*/
	17
	18	#ifndef _NET_BATMAN_ADV_BITARRAY_H_
	19	#define _NET_BATMAN_ADV_BITARRAY_H_
	20
1e2c2a4f SE	21	#include "main.h"
	22
	23	#include <linux/bitops.h>
	24	#include <linux/compiler.h>
4b426b10	25	#include <linux/stddef.h>
1e2c2a4f SE	26	#include <linux/types.h>
1e2c2a4f SE	27
62fe710f	28	/**
7afcbbef SE	29	* batadv_test_bit - check if bit is set in the current window
	30	*
	31	* @seq_bits: pointer to the sequence number receive packet
	32	* @last_seqno: latest sequence number in seq_bits
	33	* @curr_seqno: sequence number to test for
62fe710f	34	*
4b426b10 SE	35	* Return: true if the corresponding bit in the given seq_bits indicates true
4b426b10 SE	36	* and curr_seqno is within range of last_seqno. Otherwise returns false.
9cfc7bd6	37	*/
4b426b10 SE	38	static inline bool batadv_test_bit(const unsigned long *seq_bits,
4b426b10 SE	39	u32 last_seqno, u32 curr_seqno)
0079d2ce	40	{
6b5e971a	41	s32 diff;
0079d2ce SE	42
0079d2ce SE	43	diff = last_seqno - curr_seqno;
42d0b044	44	if (diff < 0 \|\| diff >= BATADV_TQ_LOCAL_WINDOW_SIZE)
4b426b10	45	return false;
24820df1	46	return test_bit(diff, seq_bits) != 0;
0079d2ce	47	}
c6c8fea2 SE	48
c6c8fea2 SE	49	/* turn corresponding bit on, so we can remember that we got the packet */
6b5e971a	50	static inline void batadv_set_bit(unsigned long *seq_bits, s32 n)
0079d2ce SE	51	{
0079d2ce SE	52	/* if too old, just drop it */
42d0b044	53	if (n < 0 \|\| n >= BATADV_TQ_LOCAL_WINDOW_SIZE)
0079d2ce	54	return;
c6c8fea2	55
0079d2ce SE	56	set_bit(n, seq_bits); /* turn the position on */
0079d2ce SE	57	}
c6c8fea2	58
4b426b10 SE	59	bool batadv_bit_get_packet(void priv, unsigned long seq_bits,
4b426b10 SE	60	s32 seq_num_diff, int set_mark);
c6c8fea2	61
c6c8fea2	62	#endif /* _NET_BATMAN_ADV_BITARRAY_H_ */