1274078Sngie/*- 2274078Sngie * Copyright (c) 2009 Sam Leffler, Errno Consulting 3274078Sngie * All rights reserved. 4274078Sngie * 5274078Sngie * Redistribution and use in source and binary forms, with or without 6274078Sngie * modification, are permitted provided that the following conditions 7274078Sngie * are met: 8274078Sngie * 1. Redistributions of source code must retain the above copyright 9274078Sngie * notice, this list of conditions and the following disclaimer. 10274078Sngie * 2. Redistributions in binary form must reproduce the above copyright 11274078Sngie * notice, this list of conditions and the following disclaimer in the 12274078Sngie * documentation and/or other materials provided with the distribution. 13274078Sngie * 14274078Sngie * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 15274078Sngie * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16274078Sngie * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17274078Sngie * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 18274078Sngie * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19274078Sngie * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20274078Sngie * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21274078Sngie * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22274078Sngie * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23274078Sngie * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24274078Sngie */ 25274078Sngie 26274078Sngie#include <sys/cdefs.h> 27274078Sngie__FBSDID("$FreeBSD$"); 28274078Sngie 29274078Sngie/* 30274078Sngie * IEEE 802.11 age queue support. 31274078Sngie */ 32274078Sngie#include "opt_wlan.h" 33274078Sngie 34274078Sngie#include <sys/param.h> 35274078Sngie#include <sys/systm.h> 36274078Sngie#include <sys/kernel.h> 37274078Sngie#include <sys/malloc.h> 38274078Sngie 39274078Sngie#include <sys/socket.h> 40274078Sngie 41274078Sngie#include <net/if.h> 42274078Sngie#include <net/if_var.h> 43274078Sngie#include <net/if_media.h> 44274078Sngie#include <net/ethernet.h> 45274078Sngie 46274078Sngie#include <net80211/ieee80211_var.h> 47274078Sngie 48274078Sngie/* 49274078Sngie * Initialize an ageq. 50274078Sngie */ 51274078Sngievoid 52274078Sngieieee80211_ageq_init(struct ieee80211_ageq *aq, int maxlen, const char *name) 53274078Sngie{ 54274078Sngie memset(aq, 0, sizeof(*aq)); 55274078Sngie aq->aq_maxlen = maxlen; 56274078Sngie IEEE80211_AGEQ_INIT(aq, name); /* OS-dependent setup */ 57274078Sngie} 58274078Sngie 59274078Sngie/* 60274078Sngie * Cleanup an ageq initialized with ieee80211_ageq_init. Note 61274078Sngie * the queue is assumed empty; this can be done with ieee80211_ageq_drain. 62274078Sngie */ 63274078Sngievoid 64274078Sngieieee80211_ageq_cleanup(struct ieee80211_ageq *aq) 65274078Sngie{ 66 KASSERT(aq->aq_len == 0, ("%d frames on ageq", aq->aq_len)); 67 IEEE80211_AGEQ_DESTROY(aq); /* OS-dependent cleanup */ 68} 69 70/* 71 * Free an mbuf according to ageq rules: if marked as holding 72 * and 802.11 frame then also reclaim a node reference from 73 * the packet header; this handles packets q'd in the tx path. 74 */ 75static void 76ageq_mfree(struct mbuf *m) 77{ 78 if (m->m_flags & M_ENCAP) { 79 struct ieee80211_node *ni = (void *) m->m_pkthdr.rcvif; 80 ieee80211_free_node(ni); 81 } 82 m->m_nextpkt = NULL; 83 m_freem(m); 84} 85 86/* 87 * Free a list of mbufs using ageq rules (see above). 88 */ 89void 90ieee80211_ageq_mfree(struct mbuf *m) 91{ 92 struct mbuf *next; 93 94 for (; m != NULL; m = next) { 95 next = m->m_nextpkt; 96 ageq_mfree(m); 97 } 98} 99 100/* 101 * Append an mbuf to the ageq and mark it with the specified max age 102 * If the frame is not removed before the age (in seconds) expires 103 * then it is reclaimed (along with any node reference). 104 */ 105int 106ieee80211_ageq_append(struct ieee80211_ageq *aq, struct mbuf *m, int age) 107{ 108 IEEE80211_AGEQ_LOCK(aq); 109 if (__predict_true(aq->aq_len < aq->aq_maxlen)) { 110 if (aq->aq_tail == NULL) { 111 aq->aq_head = m; 112 } else { 113 aq->aq_tail->m_nextpkt = m; 114 age -= M_AGE_GET(aq->aq_head); 115 } 116 KASSERT(age >= 0, ("age %d", age)); 117 M_AGE_SET(m, age); 118 m->m_nextpkt = NULL; 119 aq->aq_tail = m; 120 aq->aq_len++; 121 IEEE80211_AGEQ_UNLOCK(aq); 122 return 0; 123 } else { 124 /* 125 * No space, drop and cleanup references. 126 */ 127 aq->aq_drops++; 128 IEEE80211_AGEQ_UNLOCK(aq); 129 /* XXX tail drop? */ 130 ageq_mfree(m); 131 return ENOSPC; 132 } 133} 134 135/* 136 * Drain/reclaim all frames from an ageq. 137 */ 138void 139ieee80211_ageq_drain(struct ieee80211_ageq *aq) 140{ 141 ieee80211_ageq_mfree(ieee80211_ageq_remove(aq, NULL)); 142} 143 144/* 145 * Drain/reclaim frames associated with a specific node from an ageq. 146 */ 147void 148ieee80211_ageq_drain_node(struct ieee80211_ageq *aq, 149 struct ieee80211_node *ni) 150{ 151 ieee80211_ageq_mfree(ieee80211_ageq_remove(aq, ni)); 152} 153 154/* 155 * Age frames on the age queue. Ages are stored as time 156 * deltas (in seconds) relative to the head so we can check 157 * and/or adjust only the head of the list. If a frame's age 158 * exceeds the time quanta then remove it. The list of removed 159 * frames is returned to the caller joined by m_nextpkt. 160 */ 161struct mbuf * 162ieee80211_ageq_age(struct ieee80211_ageq *aq, int quanta) 163{ 164 struct mbuf *head, **phead; 165 struct mbuf *m; 166 167 phead = &head; 168 if (aq->aq_len != 0) { 169 IEEE80211_AGEQ_LOCK(aq); 170 while ((m = aq->aq_head) != NULL && M_AGE_GET(m) < quanta) { 171 if ((aq->aq_head = m->m_nextpkt) == NULL) 172 aq->aq_tail = NULL; 173 KASSERT(aq->aq_len > 0, ("aq len %d", aq->aq_len)); 174 aq->aq_len--; 175 /* add to private list for return */ 176 *phead = m; 177 phead = &m->m_nextpkt; 178 } 179 if (m != NULL) 180 M_AGE_SUB(m, quanta); 181 IEEE80211_AGEQ_UNLOCK(aq); 182 } 183 *phead = NULL; 184 return head; 185} 186 187/* 188 * Remove all frames matching the specified node identifier 189 * (NULL matches all). Frames are returned as a list joined 190 * by m_nextpkt. 191 */ 192struct mbuf * 193ieee80211_ageq_remove(struct ieee80211_ageq *aq, 194 struct ieee80211_node *match) 195{ 196 struct mbuf *m, **prev, *ohead; 197 struct mbuf *head, **phead; 198 199 IEEE80211_AGEQ_LOCK(aq); 200 ohead = aq->aq_head; 201 prev = &aq->aq_head; 202 phead = &head; 203 while ((m = *prev) != NULL) { 204 if (match != NULL && m->m_pkthdr.rcvif != (void *) match) { 205 prev = &m->m_nextpkt; 206 continue; 207 } 208 /* 209 * Adjust q length. 210 */ 211 KASSERT(aq->aq_len > 0, ("aq len %d", aq->aq_len)); 212 aq->aq_len--; 213 /* 214 * Remove from forward list; tail pointer is harder. 215 */ 216 if (aq->aq_tail == m) { 217 KASSERT(m->m_nextpkt == NULL, ("not last")); 218 if (aq->aq_head == m) { /* list empty */ 219 KASSERT(aq->aq_len == 0, 220 ("not empty, len %d", aq->aq_len)); 221 aq->aq_tail = NULL; 222 } else { /* must be one before */ 223 aq->aq_tail = (struct mbuf *)((uintptr_t)prev - 224 offsetof(struct mbuf, m_nextpkt)); 225 } 226 } 227 *prev = m->m_nextpkt; 228 229 /* add to private list for return */ 230 *phead = m; 231 phead = &m->m_nextpkt; 232 } 233 if (head == ohead && aq->aq_head != NULL) /* correct age */ 234 M_AGE_SET(aq->aq_head, M_AGE_GET(head)); 235 IEEE80211_AGEQ_UNLOCK(aq); 236 237 *phead = NULL; 238 return head; 239} 240