1 /*
2 * Copyright (C) 2013 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 #define SPINLOCK_T struct spinlock
42
43 /* A FIFO queue of mbufs with an optional lock. */
44 struct mbq {
45 struct mbuf *head;
46 struct mbuf *tail;
47 int count;
48 SPINLOCK_T lock;
49 };
50
51 /* XXX "destroy" does not match "init" as a name.
52 * We should also clarify whether init can be used while
53 * holding a lock, and whether mbq_safe_destroy() is a NOP.
54 */
55 void mbq_init(struct mbq *q);
56 void mbq_destroy(struct mbq *q);
57 void mbq_enqueue(struct mbq *q, struct mbuf *m);
58 struct mbuf *mbq_dequeue(struct mbq *q);
59 void mbq_purge(struct mbq *q);
60
61 /* XXX missing mbq_lock() and mbq_unlock */
62
63 void mbq_safe_init(struct mbq *q);
64 void mbq_safe_destroy(struct mbq *q);
65 void mbq_safe_enqueue(struct mbq *q, struct mbuf *m);
66 struct mbuf *mbq_safe_dequeue(struct mbq *q);
67 void mbq_safe_purge(struct mbq *q);
68
mbq_len(struct mbq * q)69 static inline unsigned int mbq_len(struct mbq *q)
70 {
71 return q->count;
72 }
73
74 #endif /* __NETMAP_MBQ_H_ */
75