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 * $FreeBSD$ 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. */ 48 struct 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 */ 59 void mbq_init(struct mbq *q); 60 void mbq_destroy(struct mbq *q); 61 void mbq_enqueue(struct mbq *q, struct mbuf *m); 62 struct mbuf *mbq_dequeue(struct mbq *q); 63 void mbq_purge(struct mbq *q); 64 65 static inline void 66 mbq_lock(struct mbq *q) 67 { 68 mtx_lock_spin(&q->lock); 69 } 70 71 static inline void 72 mbq_unlock(struct mbq *q) 73 { 74 mtx_unlock_spin(&q->lock); 75 } 76 77 78 void mbq_safe_init(struct mbq *q); 79 void mbq_safe_destroy(struct mbq *q); 80 void mbq_safe_enqueue(struct mbq *q, struct mbuf *m); 81 struct mbuf *mbq_safe_dequeue(struct mbq *q); 82 void mbq_safe_purge(struct mbq *q); 83 84 static inline unsigned int mbq_len(struct mbq *q) 85 { 86 return q->count; 87 } 88 89 #endif /* __NETMAP_MBQ_H_ */ 90