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
wme_downgrade_ac(struct sk_buff * skb)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 /* Indicate which queue to use for this fully formed 802.11 frame */
ieee80211_select_queue_80211(struct ieee80211_local * local,struct sk_buff * skb,struct ieee80211_hdr * hdr)56 u16 ieee80211_select_queue_80211(struct ieee80211_local *local,
57 struct sk_buff *skb,
58 struct ieee80211_hdr *hdr)
59 {
60 u8 *p;
61
62 if (local->hw.queues < 4)
63 return 0;
64
65 if (!ieee80211_is_data(hdr->frame_control)) {
66 skb->priority = 7;
67 return ieee802_1d_to_ac[skb->priority];
68 }
69 if (!ieee80211_is_data_qos(hdr->frame_control)) {
70 skb->priority = 0;
71 return ieee802_1d_to_ac[skb->priority];
72 }
73
74 p = ieee80211_get_qos_ctl(hdr);
75 skb->priority = *p & IEEE80211_QOS_CTL_TAG1D_MASK;
76
77 return ieee80211_downgrade_queue(local, skb);
78 }
79
80 /* Indicate which queue to use. */
ieee80211_select_queue(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb)81 u16 ieee80211_select_queue(struct ieee80211_sub_if_data *sdata,
82 struct sk_buff *skb)
83 {
84 struct ieee80211_local *local = sdata->local;
85 struct sta_info *sta = NULL;
86 const u8 *ra = NULL;
87 bool qos = false;
88
89 if (local->hw.queues < 4 || skb->len < 6) {
90 skb->priority = 0; /* required for correct WPA/11i MIC */
91 return min_t(u16, local->hw.queues - 1, IEEE80211_AC_BE);
92 }
93
94 rcu_read_lock();
95 switch (sdata->vif.type) {
96 case NL80211_IFTYPE_AP_VLAN:
97 sta = rcu_dereference(sdata->u.vlan.sta);
98 if (sta) {
99 qos = test_sta_flag(sta, WLAN_STA_WME);
100 break;
101 }
102 case NL80211_IFTYPE_AP:
103 ra = skb->data;
104 break;
105 case NL80211_IFTYPE_WDS:
106 ra = sdata->u.wds.remote_addr;
107 break;
108 #ifdef CONFIG_MAC80211_MESH
109 case NL80211_IFTYPE_MESH_POINT:
110 qos = true;
111 break;
112 #endif
113 case NL80211_IFTYPE_STATION:
114 ra = sdata->u.mgd.bssid;
115 break;
116 case NL80211_IFTYPE_ADHOC:
117 ra = skb->data;
118 break;
119 default:
120 break;
121 }
122
123 if (!sta && ra && !is_multicast_ether_addr(ra)) {
124 sta = sta_info_get(sdata, ra);
125 if (sta)
126 qos = test_sta_flag(sta, WLAN_STA_WME);
127 }
128 rcu_read_unlock();
129
130 if (!qos) {
131 skb->priority = 0; /* required for correct WPA/11i MIC */
132 return IEEE80211_AC_BE;
133 }
134
135 /* use the data classifier to determine what 802.1d tag the
136 * data frame has */
137 skb->priority = cfg80211_classify8021d(skb);
138
139 return ieee80211_downgrade_queue(local, skb);
140 }
141
ieee80211_downgrade_queue(struct ieee80211_local * local,struct sk_buff * skb)142 u16 ieee80211_downgrade_queue(struct ieee80211_local *local,
143 struct sk_buff *skb)
144 {
145 /* in case we are a client verify acm is not set for this ac */
146 while (unlikely(local->wmm_acm & BIT(skb->priority))) {
147 if (wme_downgrade_ac(skb)) {
148 /*
149 * This should not really happen. The AP has marked all
150 * lower ACs to require admission control which is not
151 * a reasonable configuration. Allow the frame to be
152 * transmitted using AC_BK as a workaround.
153 */
154 break;
155 }
156 }
157
158 /* look up which queue to use for frames with this 1d tag */
159 return ieee802_1d_to_ac[skb->priority];
160 }
161
ieee80211_set_qos_hdr(struct ieee80211_sub_if_data * sdata,struct sk_buff * skb)162 void ieee80211_set_qos_hdr(struct ieee80211_sub_if_data *sdata,
163 struct sk_buff *skb)
164 {
165 struct ieee80211_hdr *hdr = (void *)skb->data;
166 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
167
168 /* Fill in the QoS header if there is one. */
169 if (ieee80211_is_data_qos(hdr->frame_control)) {
170 u8 *p = ieee80211_get_qos_ctl(hdr);
171 u8 ack_policy, tid;
172
173 tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK;
174
175 /* preserve EOSP bit */
176 ack_policy = *p & IEEE80211_QOS_CTL_EOSP;
177
178 if (is_multicast_ether_addr(hdr->addr1) ||
179 sdata->noack_map & BIT(tid)) {
180 ack_policy |= IEEE80211_QOS_CTL_ACK_POLICY_NOACK;
181 info->flags |= IEEE80211_TX_CTL_NO_ACK;
182 }
183
184 /* qos header is 2 bytes */
185 *p++ = ack_policy | tid;
186 *p = ieee80211_vif_is_mesh(&sdata->vif) ?
187 (IEEE80211_QOS_CTL_MESH_CONTROL_PRESENT >> 8) : 0;
188 }
189 }
190