2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 2009 Sam Leffler, Errno Consulting
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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.
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
32 * IEEE 802.11 age queue support.
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/kernel.h>
39 #include <sys/malloc.h>
41 #include <sys/socket.h>
44 #include <net/if_var.h>
45 #include <net/if_media.h>
46 #include <net/ethernet.h>
48 #include <net80211/ieee80211_var.h>
54 ieee80211_ageq_init(struct ieee80211_ageq *aq, int maxlen, const char *name)
56 memset(aq, 0, sizeof(*aq));
57 aq->aq_maxlen = maxlen;
58 IEEE80211_AGEQ_INIT(aq, name); /* OS-dependent setup */
62 * Cleanup an ageq initialized with ieee80211_ageq_init. Note
63 * the queue is assumed empty; this can be done with ieee80211_ageq_drain.
66 ieee80211_ageq_cleanup(struct ieee80211_ageq *aq)
68 KASSERT(aq->aq_len == 0, ("%d frames on ageq", aq->aq_len));
69 IEEE80211_AGEQ_DESTROY(aq); /* OS-dependent cleanup */
73 * Free an mbuf according to ageq rules: if marked as holding
74 * and 802.11 frame then also reclaim a node reference from
75 * the packet header; this handles packets q'd in the tx path.
78 ageq_mfree(struct mbuf *m)
80 if (m->m_flags & M_ENCAP) {
81 struct ieee80211_node *ni = (void *) m->m_pkthdr.rcvif;
82 ieee80211_free_node(ni);
89 * Free a list of mbufs using ageq rules (see above).
92 ieee80211_ageq_mfree(struct mbuf *m)
96 for (; m != NULL; m = next) {
103 * Append an mbuf to the ageq and mark it with the specified max age
104 * If the frame is not removed before the age (in seconds) expires
105 * then it is reclaimed (along with any node reference).
108 ieee80211_ageq_append(struct ieee80211_ageq *aq, struct mbuf *m, int age)
110 IEEE80211_AGEQ_LOCK(aq);
111 if (__predict_true(aq->aq_len < aq->aq_maxlen)) {
112 if (aq->aq_tail == NULL) {
115 aq->aq_tail->m_nextpkt = m;
116 age -= M_AGE_GET(aq->aq_head);
118 KASSERT(age >= 0, ("age %d", age));
123 IEEE80211_AGEQ_UNLOCK(aq);
127 * No space, drop and cleanup references.
130 IEEE80211_AGEQ_UNLOCK(aq);
138 * Drain/reclaim all frames from an ageq.
141 ieee80211_ageq_drain(struct ieee80211_ageq *aq)
143 ieee80211_ageq_mfree(ieee80211_ageq_remove(aq, NULL));
147 * Drain/reclaim frames associated with a specific node from an ageq.
150 ieee80211_ageq_drain_node(struct ieee80211_ageq *aq,
151 struct ieee80211_node *ni)
153 ieee80211_ageq_mfree(ieee80211_ageq_remove(aq, ni));
157 * Age frames on the age queue. Ages are stored as time
158 * deltas (in seconds) relative to the head so we can check
159 * and/or adjust only the head of the list. If a frame's age
160 * exceeds the time quanta then remove it. The list of removed
161 * frames is returned to the caller joined by m_nextpkt.
164 ieee80211_ageq_age(struct ieee80211_ageq *aq, int quanta)
166 struct mbuf *head, **phead;
170 if (aq->aq_len != 0) {
171 IEEE80211_AGEQ_LOCK(aq);
172 while ((m = aq->aq_head) != NULL && M_AGE_GET(m) < quanta) {
173 if ((aq->aq_head = m->m_nextpkt) == NULL)
175 KASSERT(aq->aq_len > 0, ("aq len %d", aq->aq_len));
177 /* add to private list for return */
179 phead = &m->m_nextpkt;
182 M_AGE_SUB(m, quanta);
183 IEEE80211_AGEQ_UNLOCK(aq);
190 * Remove all frames matching the specified node identifier
191 * (NULL matches all). Frames are returned as a list joined
195 ieee80211_ageq_remove(struct ieee80211_ageq *aq,
196 struct ieee80211_node *match)
198 struct mbuf *m, **prev, *ohead;
199 struct mbuf *head, **phead;
201 IEEE80211_AGEQ_LOCK(aq);
205 while ((m = *prev) != NULL) {
206 if (match != NULL && m->m_pkthdr.rcvif != (void *) match) {
207 prev = &m->m_nextpkt;
213 KASSERT(aq->aq_len > 0, ("aq len %d", aq->aq_len));
216 * Remove from forward list; tail pointer is harder.
218 if (aq->aq_tail == m) {
219 KASSERT(m->m_nextpkt == NULL, ("not last"));
220 if (aq->aq_head == m) { /* list empty */
221 KASSERT(aq->aq_len == 0,
222 ("not empty, len %d", aq->aq_len));
224 } else { /* must be one before */
225 aq->aq_tail = (struct mbuf *)((uintptr_t)prev -
226 offsetof(struct mbuf, m_nextpkt));
229 *prev = m->m_nextpkt;
231 /* add to private list for return */
233 phead = &m->m_nextpkt;
235 if (head == ohead && aq->aq_head != NULL) /* correct age */
236 M_AGE_SET(aq->aq_head, M_AGE_GET(head));
237 IEEE80211_AGEQ_UNLOCK(aq);