1/* 2 * Copyright (C) 2013-2014 Vincenzo Maffione. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23 * SUCH DAMAGE. 24 */ 25 26/* 27 * $FreeBSD: releng/10.2/sys/dev/netmap/netmap_mbq.h 270252 2014-08-20 23:34:36Z luigi $ 28 */ 29 30 31#ifndef __NETMAP_MBQ_H__ 32#define __NETMAP_MBQ_H__ 33 34/* 35 * These function implement an mbuf tailq with an optional lock. 36 * The base functions act ONLY ON THE QUEUE, whereas the "safe" 37 * variants (mbq_safe_*) also handle the lock. 38 */ 39 40/* XXX probably rely on a previous definition of SPINLOCK_T */ 41#ifdef linux 42#define SPINLOCK_T safe_spinlock_t 43#else 44#define SPINLOCK_T struct mtx 45#endif 46 47/* A FIFO queue of mbufs with an optional lock. */ 48struct mbq { 49 struct mbuf *head; 50 struct mbuf *tail; 51 int count; 52 SPINLOCK_T lock; 53}; 54 55/* XXX "destroy" does not match "init" as a name. 56 * We should also clarify whether init can be used while 57 * holding a lock, and whether mbq_safe_destroy() is a NOP. 58 */ 59void mbq_init(struct mbq *q); 60void mbq_destroy(struct mbq *q); 61void mbq_enqueue(struct mbq *q, struct mbuf *m); 62struct mbuf *mbq_dequeue(struct mbq *q); 63void mbq_purge(struct mbq *q); 64 65static inline void 66mbq_lock(struct mbq *q) 67{ 68 mtx_lock_spin(&q->lock); 69} 70 71static inline void 72mbq_unlock(struct mbq *q) 73{ 74 mtx_unlock_spin(&q->lock); 75} 76 77 78void mbq_safe_init(struct mbq *q); 79void mbq_safe_destroy(struct mbq *q); 80void mbq_safe_enqueue(struct mbq *q, struct mbuf *m); 81struct mbuf *mbq_safe_dequeue(struct mbq *q); 82void mbq_safe_purge(struct mbq *q); 83 84static inline unsigned int mbq_len(struct mbq *q) 85{ 86 return q->count; 87} 88 89#endif /* __NETMAP_MBQ_H_ */ 90