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 = get_sta_flags(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 /* 87 * XXX: This is clearly broken ... but already was before, 88 * because ieee80211_fill_mesh_addresses() would clear A1 89 * except for multicast addresses. 90 */ 91 break; 92 #endif 93 case NL80211_IFTYPE_STATION: 94 ra = sdata->u.mgd.bssid; 95 break; 96 case NL80211_IFTYPE_ADHOC: 97 ra = skb->data; 98 break; 99 default: 100 break; 101 } 102 103 if (!sta && ra && !is_multicast_ether_addr(ra)) { 104 sta = sta_info_get(sdata, ra); 105 if (sta) 106 qos = get_sta_flags(sta) & WLAN_STA_WME; 107 } 108 rcu_read_unlock(); 109 110 if (!qos) { 111 skb->priority = 0; /* required for correct WPA/11i MIC */ 112 return IEEE80211_AC_BE; 113 } 114 115 /* use the data classifier to determine what 802.1d tag the 116 * data frame has */ 117 skb->priority = cfg80211_classify8021d(skb); 118 119 return ieee80211_downgrade_queue(local, skb); 120 } 121 122 u16 ieee80211_downgrade_queue(struct ieee80211_local *local, 123 struct sk_buff *skb) 124 { 125 /* in case we are a client verify acm is not set for this ac */ 126 while (unlikely(local->wmm_acm & BIT(skb->priority))) { 127 if (wme_downgrade_ac(skb)) { 128 /* 129 * This should not really happen. The AP has marked all 130 * lower ACs to require admission control which is not 131 * a reasonable configuration. Allow the frame to be 132 * transmitted using AC_BK as a workaround. 133 */ 134 break; 135 } 136 } 137 138 /* look up which queue to use for frames with this 1d tag */ 139 return ieee802_1d_to_ac[skb->priority]; 140 } 141 142 void ieee80211_set_qos_hdr(struct ieee80211_local *local, struct sk_buff *skb) 143 { 144 struct ieee80211_hdr *hdr = (void *)skb->data; 145 146 /* Fill in the QoS header if there is one. */ 147 if (ieee80211_is_data_qos(hdr->frame_control)) { 148 u8 *p = ieee80211_get_qos_ctl(hdr); 149 u8 ack_policy = 0, tid; 150 151 tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK; 152 153 if (unlikely(local->wifi_wme_noack_test)) 154 ack_policy |= QOS_CONTROL_ACK_POLICY_NOACK << 155 QOS_CONTROL_ACK_POLICY_SHIFT; 156 /* qos header is 2 bytes, second reserved */ 157 *p++ = ack_policy | tid; 158 *p = 0; 159 } 160 } 161