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] = { 25 IEEE80211_AC_BE, 26 IEEE80211_AC_BK, 27 IEEE80211_AC_BK, 28 IEEE80211_AC_BE, 29 IEEE80211_AC_VI, 30 IEEE80211_AC_VI, 31 IEEE80211_AC_VO, 32 IEEE80211_AC_VO 33 }; 34 35 static int wme_downgrade_ac(struct sk_buff *skb) 36 { 37 switch (skb->priority) { 38 case 6: 39 case 7: 40 skb->priority = 5; /* VO -> VI */ 41 return 0; 42 case 4: 43 case 5: 44 skb->priority = 3; /* VI -> BE */ 45 return 0; 46 case 0: 47 case 3: 48 skb->priority = 2; /* BE -> BK */ 49 return 0; 50 default: 51 return -1; 52 } 53 } 54 55 56 /* Indicate which queue to use. */ 57 u16 ieee80211_select_queue(struct ieee80211_sub_if_data *sdata, 58 struct sk_buff *skb) 59 { 60 struct ieee80211_local *local = sdata->local; 61 struct sta_info *sta = NULL; 62 const u8 *ra = NULL; 63 bool qos = false; 64 65 if (local->hw.queues < 4 || skb->len < 6) { 66 skb->priority = 0; /* required for correct WPA/11i MIC */ 67 return min_t(u16, local->hw.queues - 1, IEEE80211_AC_BE); 68 } 69 70 rcu_read_lock(); 71 switch (sdata->vif.type) { 72 case NL80211_IFTYPE_AP_VLAN: 73 sta = rcu_dereference(sdata->u.vlan.sta); 74 if (sta) { 75 qos = test_sta_flag(sta, WLAN_STA_WME); 76 break; 77 } 78 case NL80211_IFTYPE_AP: 79 ra = skb->data; 80 break; 81 case NL80211_IFTYPE_WDS: 82 ra = sdata->u.wds.remote_addr; 83 break; 84 #ifdef CONFIG_MAC80211_MESH 85 case NL80211_IFTYPE_MESH_POINT: 86 ra = skb->data; 87 break; 88 #endif 89 case NL80211_IFTYPE_STATION: 90 ra = sdata->u.mgd.bssid; 91 break; 92 case NL80211_IFTYPE_ADHOC: 93 ra = skb->data; 94 break; 95 default: 96 break; 97 } 98 99 if (!sta && ra && !is_multicast_ether_addr(ra)) { 100 sta = sta_info_get(sdata, ra); 101 if (sta) 102 qos = test_sta_flag(sta, WLAN_STA_WME); 103 } 104 rcu_read_unlock(); 105 106 if (!qos) { 107 skb->priority = 0; /* required for correct WPA/11i MIC */ 108 return IEEE80211_AC_BE; 109 } 110 111 /* use the data classifier to determine what 802.1d tag the 112 * data frame has */ 113 skb->priority = cfg80211_classify8021d(skb); 114 115 return ieee80211_downgrade_queue(local, skb); 116 } 117 118 u16 ieee80211_downgrade_queue(struct ieee80211_local *local, 119 struct sk_buff *skb) 120 { 121 /* in case we are a client verify acm is not set for this ac */ 122 while (unlikely(local->wmm_acm & BIT(skb->priority))) { 123 if (wme_downgrade_ac(skb)) { 124 /* 125 * This should not really happen. The AP has marked all 126 * lower ACs to require admission control which is not 127 * a reasonable configuration. Allow the frame to be 128 * transmitted using AC_BK as a workaround. 129 */ 130 break; 131 } 132 } 133 134 /* look up which queue to use for frames with this 1d tag */ 135 return ieee802_1d_to_ac[skb->priority]; 136 } 137 138 void ieee80211_set_qos_hdr(struct ieee80211_sub_if_data *sdata, 139 struct sk_buff *skb) 140 { 141 struct ieee80211_hdr *hdr = (void *)skb->data; 142 143 /* Fill in the QoS header if there is one. */ 144 if (ieee80211_is_data_qos(hdr->frame_control)) { 145 u8 *p = ieee80211_get_qos_ctl(hdr); 146 u8 ack_policy = 0, tid; 147 148 tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK; 149 150 if (unlikely(sdata->local->wifi_wme_noack_test)) 151 ack_policy |= IEEE80211_QOS_CTL_ACK_POLICY_NOACK; 152 /* qos header is 2 bytes */ 153 *p++ = ack_policy | tid; 154 *p = ieee80211_vif_is_mesh(&sdata->vif) ? 155 (IEEE80211_QOS_CTL_MESH_CONTROL_PRESENT >> 8) : 0; 156 } 157 } 158