1/*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (C) 2013-2014 Vincenzo Maffione 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29/* 30 * $FreeBSD$ 31 */ 32 33 34#ifndef _NET_NETMAP_MBQ_H__ 35#define _NET_NETMAP_MBQ_H__ 36 37/* 38 * These function implement an mbuf tailq with an optional lock. 39 * The base functions act ONLY ON THE QUEUE, whereas the "safe" 40 * variants (mbq_safe_*) also handle the lock. 41 */ 42 43/* XXX probably rely on a previous definition of SPINLOCK_T */ 44#ifdef linux 45#define SPINLOCK_T safe_spinlock_t 46#elif defined (_WIN32) 47#define SPINLOCK_T win_spinlock_t 48#else 49#define SPINLOCK_T struct mtx 50#endif 51 52/* A FIFO queue of mbufs with an optional lock. */ 53struct mbq { 54 struct mbuf *head; 55 struct mbuf *tail; 56 int count; 57 SPINLOCK_T lock; 58}; 59 60/* We should clarify whether init can be used while 61 * holding a lock, and whether mbq_safe_destroy() is a NOP. 62 */ 63void mbq_init(struct mbq *q); 64void mbq_fini(struct mbq *q); 65void mbq_enqueue(struct mbq *q, struct mbuf *m); 66struct mbuf *mbq_dequeue(struct mbq *q); 67void mbq_purge(struct mbq *q); 68 69static inline struct mbuf * 70mbq_peek(struct mbq *q) 71{ 72 return q->head; 73} 74 75static inline void 76mbq_lock(struct mbq *q) 77{ 78 mtx_lock_spin(&q->lock); 79} 80 81static inline void 82mbq_unlock(struct mbq *q) 83{ 84 mtx_unlock_spin(&q->lock); 85} 86 87 88void mbq_safe_init(struct mbq *q); 89void mbq_safe_fini(struct mbq *q); 90void mbq_safe_enqueue(struct mbq *q, struct mbuf *m); 91struct mbuf *mbq_safe_dequeue(struct mbq *q); 92void mbq_safe_purge(struct mbq *q); 93 94static inline unsigned int mbq_len(struct mbq *q) 95{ 96 return q->count; 97} 98 99#endif /* _NET_NETMAP_MBQ_H_ */ 100