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 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 */ 27 static 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 */ 44 static 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 53 bool 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