1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* Copyright (C) 2006-2019 B.A.T.M.A.N. contributors: 3 * 4 * Simon Wunderlich, Marek Lindner 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of version 2 of the GNU General Public 8 * License as published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope that it will be useful, but 11 * WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 * General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, see <http://www.gnu.org/licenses/>. 17 */ 18 19 #ifndef _NET_BATMAN_ADV_BITARRAY_H_ 20 #define _NET_BATMAN_ADV_BITARRAY_H_ 21 22 #include "main.h" 23 24 #include <linux/bitops.h> 25 #include <linux/compiler.h> 26 #include <linux/stddef.h> 27 #include <linux/types.h> 28 29 /** 30 * batadv_test_bit() - check if bit is set in the current window 31 * 32 * @seq_bits: pointer to the sequence number receive packet 33 * @last_seqno: latest sequence number in seq_bits 34 * @curr_seqno: sequence number to test for 35 * 36 * Return: true if the corresponding bit in the given seq_bits indicates true 37 * and curr_seqno is within range of last_seqno. Otherwise returns false. 38 */ 39 static inline bool batadv_test_bit(const unsigned long *seq_bits, 40 u32 last_seqno, u32 curr_seqno) 41 { 42 s32 diff; 43 44 diff = last_seqno - curr_seqno; 45 if (diff < 0 || diff >= BATADV_TQ_LOCAL_WINDOW_SIZE) 46 return false; 47 return test_bit(diff, seq_bits) != 0; 48 } 49 50 /** 51 * batadv_set_bit() - Turn corresponding bit on, so we can remember that we got 52 * the packet 53 * @seq_bits: bitmap of the packet receive window 54 * @n: relative sequence number of newly received packet 55 */ 56 static inline void batadv_set_bit(unsigned long *seq_bits, s32 n) 57 { 58 /* if too old, just drop it */ 59 if (n < 0 || n >= BATADV_TQ_LOCAL_WINDOW_SIZE) 60 return; 61 62 set_bit(n, seq_bits); /* turn the position on */ 63 } 64 65 bool batadv_bit_get_packet(void *priv, unsigned long *seq_bits, 66 s32 seq_num_diff, int set_mark); 67 68 #endif /* _NET_BATMAN_ADV_BITARRAY_H_ */ 69