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 int wme_downgrade_ac(struct sk_buff *skb) 27 { 28 switch (skb->priority) { 29 case 6: 30 case 7: 31 skb->priority = 5; /* VO -> VI */ 32 return 0; 33 case 4: 34 case 5: 35 skb->priority = 3; /* VI -> BE */ 36 return 0; 37 case 0: 38 case 3: 39 skb->priority = 2; /* BE -> BK */ 40 return 0; 41 default: 42 return -1; 43 } 44 } 45 46 47 /* Indicate which queue to use. */ 48 u16 ieee80211_select_queue(struct ieee80211_sub_if_data *sdata, 49 struct sk_buff *skb) 50 { 51 struct ieee80211_local *local = sdata->local; 52 struct sta_info *sta = NULL; 53 u32 sta_flags = 0; 54 const u8 *ra = NULL; 55 bool qos = false; 56 57 if (local->hw.queues < 4 || skb->len < 6) { 58 skb->priority = 0; /* required for correct WPA/11i MIC */ 59 return min_t(u16, local->hw.queues - 1, 60 ieee802_1d_to_ac[skb->priority]); 61 } 62 63 rcu_read_lock(); 64 switch (sdata->vif.type) { 65 case NL80211_IFTYPE_AP_VLAN: 66 rcu_read_lock(); 67 sta = rcu_dereference(sdata->u.vlan.sta); 68 if (sta) 69 sta_flags = get_sta_flags(sta); 70 rcu_read_unlock(); 71 if (sta) 72 break; 73 case NL80211_IFTYPE_AP: 74 ra = skb->data; 75 break; 76 case NL80211_IFTYPE_WDS: 77 ra = sdata->u.wds.remote_addr; 78 break; 79 #ifdef CONFIG_MAC80211_MESH 80 case NL80211_IFTYPE_MESH_POINT: 81 /* 82 * XXX: This is clearly broken ... but already was before, 83 * because ieee80211_fill_mesh_addresses() would clear A1 84 * except for multicast addresses. 85 */ 86 break; 87 #endif 88 case NL80211_IFTYPE_STATION: 89 ra = sdata->u.mgd.bssid; 90 break; 91 case NL80211_IFTYPE_ADHOC: 92 ra = skb->data; 93 break; 94 default: 95 break; 96 } 97 98 if (!sta && ra && !is_multicast_ether_addr(ra)) { 99 sta = sta_info_get(sdata, ra); 100 if (sta) 101 sta_flags = get_sta_flags(sta); 102 } 103 104 if (sta_flags & WLAN_STA_WME) 105 qos = true; 106 107 rcu_read_unlock(); 108 109 if (!qos) { 110 skb->priority = 0; /* required for correct WPA/11i MIC */ 111 return ieee802_1d_to_ac[skb->priority]; 112 } 113 114 /* use the data classifier to determine what 802.1d tag the 115 * data frame has */ 116 skb->priority = cfg80211_classify8021d(skb); 117 118 return ieee80211_downgrade_queue(local, skb); 119 } 120 121 u16 ieee80211_downgrade_queue(struct ieee80211_local *local, 122 struct sk_buff *skb) 123 { 124 /* in case we are a client verify acm is not set for this ac */ 125 while (unlikely(local->wmm_acm & BIT(skb->priority))) { 126 if (wme_downgrade_ac(skb)) { 127 /* 128 * This should not really happen. The AP has marked all 129 * lower ACs to require admission control which is not 130 * a reasonable configuration. Allow the frame to be 131 * transmitted using AC_BK as a workaround. 132 */ 133 break; 134 } 135 } 136 137 /* look up which queue to use for frames with this 1d tag */ 138 return ieee802_1d_to_ac[skb->priority]; 139 } 140 141 void ieee80211_set_qos_hdr(struct ieee80211_local *local, struct sk_buff *skb) 142 { 143 struct ieee80211_hdr *hdr = (void *)skb->data; 144 145 /* Fill in the QoS header if there is one. */ 146 if (ieee80211_is_data_qos(hdr->frame_control)) { 147 u8 *p = ieee80211_get_qos_ctl(hdr); 148 u8 ack_policy = 0, tid; 149 150 tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK; 151 152 if (unlikely(local->wifi_wme_noack_test)) 153 ack_policy |= QOS_CONTROL_ACK_POLICY_NOACK << 154 QOS_CONTROL_ACK_POLICY_SHIFT; 155 /* qos header is 2 bytes, second reserved */ 156 *p++ = ack_policy | tid; 157 *p = 0; 158 } 159 } 160