xref: /freebsd/sys/dev/netmap/netmap_mbq.c (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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  */
31 
32 
33 #ifdef linux
34 #include "bsd_glue.h"
35 #elif defined (_WIN32)
36 #include "win_glue.h"
37 #else   /* __FreeBSD__ */
38 #include <sys/param.h>
39 #include <sys/lock.h>
40 #include <sys/mutex.h>
41 #include <sys/systm.h>
42 #include <sys/mbuf.h>
43 #endif  /* __FreeBSD__ */
44 
45 #include "netmap_mbq.h"
46 
47 
48 static inline void __mbq_init(struct mbq *q)
49 {
50     q->head = q->tail = NULL;
51     q->count = 0;
52 }
53 
54 
55 void mbq_safe_init(struct mbq *q)
56 {
57     mtx_init(&q->lock, "mbq", NULL, MTX_SPIN);
58     __mbq_init(q);
59 }
60 
61 
62 void mbq_init(struct mbq *q)
63 {
64     __mbq_init(q);
65 }
66 
67 
68 static inline void __mbq_enqueue(struct mbq *q, struct mbuf *m)
69 {
70     m->m_nextpkt = NULL;
71     if (q->tail) {
72         q->tail->m_nextpkt = m;
73         q->tail = m;
74     } else {
75         q->head = q->tail = m;
76     }
77     q->count++;
78 }
79 
80 
81 void mbq_safe_enqueue(struct mbq *q, struct mbuf *m)
82 {
83     mbq_lock(q);
84     __mbq_enqueue(q, m);
85     mbq_unlock(q);
86 }
87 
88 
89 void mbq_enqueue(struct mbq *q, struct mbuf *m)
90 {
91     __mbq_enqueue(q, m);
92 }
93 
94 
95 static inline struct mbuf *__mbq_dequeue(struct mbq *q)
96 {
97     struct mbuf *ret = NULL;
98 
99     if (q->head) {
100         ret = q->head;
101         q->head = ret->m_nextpkt;
102         if (q->head == NULL) {
103             q->tail = NULL;
104         }
105         q->count--;
106         ret->m_nextpkt = NULL;
107     }
108 
109     return ret;
110 }
111 
112 
113 struct mbuf *mbq_safe_dequeue(struct mbq *q)
114 {
115     struct mbuf *ret;
116 
117     mbq_lock(q);
118     ret =  __mbq_dequeue(q);
119     mbq_unlock(q);
120 
121     return ret;
122 }
123 
124 
125 struct mbuf *mbq_dequeue(struct mbq *q)
126 {
127     return __mbq_dequeue(q);
128 }
129 
130 
131 /* XXX seems pointless to have a generic purge */
132 static void __mbq_purge(struct mbq *q, int safe)
133 {
134     struct mbuf *m;
135 
136     for (;;) {
137         m = safe ? mbq_safe_dequeue(q) : mbq_dequeue(q);
138         if (m) {
139             m_freem(m);
140         } else {
141             break;
142         }
143     }
144 }
145 
146 
147 void mbq_purge(struct mbq *q)
148 {
149     __mbq_purge(q, 0);
150 }
151 
152 
153 void mbq_safe_purge(struct mbq *q)
154 {
155     __mbq_purge(q, 1);
156 }
157 
158 
159 void mbq_safe_fini(struct mbq *q)
160 {
161     mtx_destroy(&q->lock);
162 }
163 
164 
165 void mbq_fini(struct mbq *q)
166 {
167 }
168