1 /* 2 * Copyright 2004, Instant802 Networks, Inc. 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 */ 8 9 #include <linux/netdevice.h> 10 #include <linux/skbuff.h> 11 #include <linux/module.h> 12 #include <linux/if_arp.h> 13 #include <linux/types.h> 14 #include <net/ip.h> 15 #include <net/pkt_sched.h> 16 17 #include <net/mac80211.h> 18 #include "ieee80211_i.h" 19 #include "wme.h" 20 21 /* Default mapping in classifier to work with default 22 * queue setup. 23 */ 24 const int ieee802_1d_to_ac[8] = { 2, 3, 3, 2, 1, 1, 0, 0 }; 25 26 static const char llc_ip_hdr[8] = {0xAA, 0xAA, 0x3, 0, 0, 0, 0x08, 0}; 27 28 /* Given a data frame determine the 802.1p/1d tag to use. */ 29 static unsigned int classify_1d(struct sk_buff *skb) 30 { 31 unsigned int dscp; 32 33 /* skb->priority values from 256->263 are magic values to 34 * directly indicate a specific 802.1d priority. This is used 35 * to allow 802.1d priority to be passed directly in from VLAN 36 * tags, etc. 37 */ 38 if (skb->priority >= 256 && skb->priority <= 263) 39 return skb->priority - 256; 40 41 switch (skb->protocol) { 42 case __constant_htons(ETH_P_IP): 43 dscp = ip_hdr(skb)->tos & 0xfc; 44 break; 45 46 default: 47 return 0; 48 } 49 50 return dscp >> 5; 51 } 52 53 54 static int wme_downgrade_ac(struct sk_buff *skb) 55 { 56 switch (skb->priority) { 57 case 6: 58 case 7: 59 skb->priority = 5; /* VO -> VI */ 60 return 0; 61 case 4: 62 case 5: 63 skb->priority = 3; /* VI -> BE */ 64 return 0; 65 case 0: 66 case 3: 67 skb->priority = 2; /* BE -> BK */ 68 return 0; 69 default: 70 return -1; 71 } 72 } 73 74 75 /* Indicate which queue to use. */ 76 static u16 classify80211(struct sk_buff *skb, struct net_device *dev) 77 { 78 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); 79 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 80 81 if (!ieee80211_is_data(hdr->frame_control)) { 82 /* management frames go on AC_VO queue, but are sent 83 * without QoS control fields */ 84 return 0; 85 } 86 87 if (0 /* injected */) { 88 /* use AC from radiotap */ 89 } 90 91 if (!ieee80211_is_data_qos(hdr->frame_control)) { 92 skb->priority = 0; /* required for correct WPA/11i MIC */ 93 return ieee802_1d_to_ac[skb->priority]; 94 } 95 96 /* use the data classifier to determine what 802.1d tag the 97 * data frame has */ 98 skb->priority = classify_1d(skb); 99 100 /* in case we are a client verify acm is not set for this ac */ 101 while (unlikely(local->wmm_acm & BIT(skb->priority))) { 102 if (wme_downgrade_ac(skb)) { 103 /* The old code would drop the packet in this 104 * case. 105 */ 106 return 0; 107 } 108 } 109 110 /* look up which queue to use for frames with this 1d tag */ 111 return ieee802_1d_to_ac[skb->priority]; 112 } 113 114 u16 ieee80211_select_queue(struct net_device *dev, struct sk_buff *skb) 115 { 116 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 117 struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); 118 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 119 struct sta_info *sta; 120 u16 queue; 121 u8 tid; 122 123 queue = classify80211(skb, dev); 124 if (unlikely(queue >= local->hw.queues)) 125 queue = local->hw.queues - 1; 126 127 if (info->flags & IEEE80211_TX_CTL_REQUEUE) { 128 rcu_read_lock(); 129 sta = sta_info_get(local, hdr->addr1); 130 tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK; 131 if (sta) { 132 struct ieee80211_hw *hw = &local->hw; 133 int ampdu_queue = sta->tid_to_tx_q[tid]; 134 135 if ((ampdu_queue < ieee80211_num_queues(hw)) && 136 test_bit(ampdu_queue, local->queue_pool)) { 137 queue = ampdu_queue; 138 info->flags |= IEEE80211_TX_CTL_AMPDU; 139 } else { 140 info->flags &= ~IEEE80211_TX_CTL_AMPDU; 141 } 142 } 143 rcu_read_unlock(); 144 145 return queue; 146 } 147 148 /* Now we know the 1d priority, fill in the QoS header if 149 * there is one. 150 */ 151 if (ieee80211_is_data_qos(hdr->frame_control)) { 152 u8 *p = ieee80211_get_qos_ctl(hdr); 153 u8 ack_policy = 0; 154 tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK; 155 if (local->wifi_wme_noack_test) 156 ack_policy |= QOS_CONTROL_ACK_POLICY_NOACK << 157 QOS_CONTROL_ACK_POLICY_SHIFT; 158 /* qos header is 2 bytes, second reserved */ 159 *p++ = ack_policy | tid; 160 *p = 0; 161 162 rcu_read_lock(); 163 164 sta = sta_info_get(local, hdr->addr1); 165 if (sta) { 166 int ampdu_queue = sta->tid_to_tx_q[tid]; 167 struct ieee80211_hw *hw = &local->hw; 168 169 if ((ampdu_queue < ieee80211_num_queues(hw)) && 170 test_bit(ampdu_queue, local->queue_pool)) { 171 queue = ampdu_queue; 172 info->flags |= IEEE80211_TX_CTL_AMPDU; 173 } else { 174 info->flags &= ~IEEE80211_TX_CTL_AMPDU; 175 } 176 } 177 178 rcu_read_unlock(); 179 } 180 181 return queue; 182 } 183 184 int ieee80211_ht_agg_queue_add(struct ieee80211_local *local, 185 struct sta_info *sta, u16 tid) 186 { 187 int i; 188 189 /* XXX: currently broken due to cb/requeue use */ 190 return -EPERM; 191 192 /* prepare the filter and save it for the SW queue 193 * matching the received HW queue */ 194 195 if (!local->hw.ampdu_queues) 196 return -EPERM; 197 198 /* try to get a Qdisc from the pool */ 199 for (i = local->hw.queues; i < ieee80211_num_queues(&local->hw); i++) 200 if (!test_and_set_bit(i, local->queue_pool)) { 201 ieee80211_stop_queue(local_to_hw(local), i); 202 sta->tid_to_tx_q[tid] = i; 203 204 /* IF there are already pending packets 205 * on this tid first we need to drain them 206 * on the previous queue 207 * since HT is strict in order */ 208 #ifdef CONFIG_MAC80211_HT_DEBUG 209 if (net_ratelimit()) { 210 DECLARE_MAC_BUF(mac); 211 printk(KERN_DEBUG "allocated aggregation queue" 212 " %d tid %d addr %s pool=0x%lX\n", 213 i, tid, print_mac(mac, sta->addr), 214 local->queue_pool[0]); 215 } 216 #endif /* CONFIG_MAC80211_HT_DEBUG */ 217 return 0; 218 } 219 220 return -EAGAIN; 221 } 222 223 /** 224 * the caller needs to hold netdev_get_tx_queue(local->mdev, X)->lock 225 */ 226 void ieee80211_ht_agg_queue_remove(struct ieee80211_local *local, 227 struct sta_info *sta, u16 tid, 228 u8 requeue) 229 { 230 int agg_queue = sta->tid_to_tx_q[tid]; 231 struct ieee80211_hw *hw = &local->hw; 232 233 /* return the qdisc to the pool */ 234 clear_bit(agg_queue, local->queue_pool); 235 sta->tid_to_tx_q[tid] = ieee80211_num_queues(hw); 236 237 if (requeue) { 238 ieee80211_requeue(local, agg_queue); 239 } else { 240 struct netdev_queue *txq; 241 spinlock_t *root_lock; 242 struct Qdisc *q; 243 244 txq = netdev_get_tx_queue(local->mdev, agg_queue); 245 q = rcu_dereference(txq->qdisc); 246 root_lock = qdisc_lock(q); 247 248 spin_lock_bh(root_lock); 249 qdisc_reset(q); 250 spin_unlock_bh(root_lock); 251 } 252 } 253 254 void ieee80211_requeue(struct ieee80211_local *local, int queue) 255 { 256 struct netdev_queue *txq = netdev_get_tx_queue(local->mdev, queue); 257 struct sk_buff_head list; 258 spinlock_t *root_lock; 259 struct Qdisc *qdisc; 260 u32 len; 261 262 rcu_read_lock_bh(); 263 264 qdisc = rcu_dereference(txq->qdisc); 265 if (!qdisc || !qdisc->dequeue) 266 goto out_unlock; 267 268 skb_queue_head_init(&list); 269 270 root_lock = qdisc_root_lock(qdisc); 271 spin_lock(root_lock); 272 for (len = qdisc->q.qlen; len > 0; len--) { 273 struct sk_buff *skb = qdisc->dequeue(qdisc); 274 275 if (skb) 276 __skb_queue_tail(&list, skb); 277 } 278 spin_unlock(root_lock); 279 280 for (len = list.qlen; len > 0; len--) { 281 struct sk_buff *skb = __skb_dequeue(&list); 282 u16 new_queue; 283 284 BUG_ON(!skb); 285 new_queue = ieee80211_select_queue(local->mdev, skb); 286 skb_set_queue_mapping(skb, new_queue); 287 288 txq = netdev_get_tx_queue(local->mdev, new_queue); 289 290 291 qdisc = rcu_dereference(txq->qdisc); 292 root_lock = qdisc_root_lock(qdisc); 293 294 spin_lock(root_lock); 295 qdisc_enqueue_root(skb, qdisc); 296 spin_unlock(root_lock); 297 } 298 299 out_unlock: 300 rcu_read_unlock_bh(); 301 } 302