1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
|
From: Felix Fietkau <nbd@openwrt.org>
Date: Fri, 5 Feb 2016 01:38:51 +0100
Subject: [PATCH] mac80211: add A-MSDU tx support
Requires software tx queueing support. frag_list support (for zero-copy)
is optional.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
---
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -709,6 +709,7 @@ enum mac80211_tx_info_flags {
* @IEEE80211_TX_CTRL_PS_RESPONSE: This frame is a response to a poll
* frame (PS-Poll or uAPSD).
* @IEEE80211_TX_CTRL_RATE_INJECT: This frame is injected with rate information
+ * @IEEE80211_TX_CTRL_AMSDU: This frame is an A-MSDU frame
*
* These flags are used in tx_info->control.flags.
*/
@@ -716,6 +717,7 @@ enum mac80211_tx_control_flags {
IEEE80211_TX_CTRL_PORT_CTRL_PROTO = BIT(0),
IEEE80211_TX_CTRL_PS_RESPONSE = BIT(1),
IEEE80211_TX_CTRL_RATE_INJECT = BIT(2),
+ IEEE80211_TX_CTRL_AMSDU = BIT(3),
};
/*
@@ -1961,6 +1963,12 @@ struct ieee80211_txq {
* order and does not need to manage its own reorder buffer or BA session
* timeout.
*
+ * @IEEE80211_HW_TX_AMSDU: Hardware (or driver) supports software aggregated
+ * A-MSDU frames. Requires software tx queueing support.
+ *
+ * @IEEE80211_HW_TX_FRAG_LIST: Hardware (or driver) supports sending frag_list
+ * skbs, needed for zero-copy software A-MSDU.
+ *
* @NUM_IEEE80211_HW_FLAGS: number of hardware flags, used for sizing arrays
*/
enum ieee80211_hw_flags {
@@ -1998,6 +2006,8 @@ enum ieee80211_hw_flags {
IEEE80211_HW_BEACON_TX_STATUS,
IEEE80211_HW_NEEDS_UNIQUE_STA_ADDR,
IEEE80211_HW_SUPPORTS_REORDERING_BUFFER,
+ IEEE80211_HW_TX_AMSDU,
+ IEEE80211_HW_TX_FRAG_LIST,
/* keep last, obviously */
NUM_IEEE80211_HW_FLAGS
@@ -2070,6 +2080,9 @@ enum ieee80211_hw_flags {
* size is smaller (an example is LinkSys WRT120N with FW v1.0.07
* build 002 Jun 18 2012).
*
+ * @max_tx_amsdu_subframes: maximum number of subframes used in software
+ * A-MSDU aggregation
+ *
* @offchannel_tx_hw_queue: HW queue ID to use for offchannel TX
* (if %IEEE80211_HW_QUEUE_CONTROL is set)
*
@@ -2124,6 +2137,7 @@ struct ieee80211_hw {
u8 max_rate_tries;
u8 max_rx_aggregation_subframes;
u8 max_tx_aggregation_subframes;
+ u8 max_tx_amsdu_subframes;
u8 offchannel_tx_hw_queue;
u8 radiotap_mcs_details;
u16 radiotap_vht_details;
--- a/net/mac80211/agg-tx.c
+++ b/net/mac80211/agg-tx.c
@@ -935,6 +935,7 @@ void ieee80211_process_addba_resp(struct
size_t len)
{
struct tid_ampdu_tx *tid_tx;
+ struct ieee80211_txq *txq;
u16 capab, tid;
u8 buf_size;
bool amsdu;
@@ -945,6 +946,10 @@ void ieee80211_process_addba_resp(struct
buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
buf_size = min(buf_size, local->hw.max_tx_aggregation_subframes);
+ txq = sta->sta.txq[tid];
+ if (!amsdu && txq)
+ set_bit(IEEE80211_TXQ_NO_AMSDU, &to_txq_info(txq)->flags);
+
mutex_lock(&sta->ampdu_mlme.mtx);
tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
--- a/net/mac80211/debugfs.c
+++ b/net/mac80211/debugfs.c
@@ -127,6 +127,8 @@ static const char *hw_flag_names[NUM_IEE
FLAG(BEACON_TX_STATUS),
FLAG(NEEDS_UNIQUE_STA_ADDR),
FLAG(SUPPORTS_REORDERING_BUFFER),
+ FLAG(TX_AMSDU),
+ FLAG(TX_FRAG_LIST),
/* keep last for the build bug below */
(void *)0x1
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -799,6 +799,7 @@ struct mac80211_qos_map {
enum txq_info_flags {
IEEE80211_TXQ_STOP,
IEEE80211_TXQ_AMPDU,
+ IEEE80211_TXQ_NO_AMSDU,
};
struct txq_info {
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -1318,6 +1318,10 @@ struct sk_buff *ieee80211_tx_dequeue(str
out:
spin_unlock_bh(&txqi->queue.lock);
+ if (skb && skb_has_frag_list(skb) &&
+ !ieee80211_hw_check(&local->hw, TX_FRAG_LIST))
+ skb_linearize(skb);
+
return skb;
}
EXPORT_SYMBOL(ieee80211_tx_dequeue);
@@ -2757,6 +2761,149 @@ void ieee80211_clear_fast_xmit(struct st
kfree_rcu(fast_tx, rcu_head);
}
+static int ieee80211_amsdu_pad(struct sk_buff *skb, int subframe_len)
+{
+ int amsdu_len = subframe_len + sizeof(struct ethhdr);
+ int padding = (4 - amsdu_len) & 3;
+
+ if (padding)
+ memset(skb_put(skb, padding), 0, padding);
+
+ return padding;
+}
+
+static bool ieee80211_amsdu_prepare_head(struct ieee80211_sub_if_data *sdata,
+ struct ieee80211_fast_tx *fast_tx,
+ struct sk_buff *skb)
+{
+ struct ieee80211_local *local = sdata->local;
+ struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+ struct ieee80211_hdr *hdr;
+ struct ethhdr amsdu_hdr;
+ int hdr_len = fast_tx->hdr_len - sizeof(rfc1042_header);
+ int subframe_len = skb->len - hdr_len;
+ void *data;
+ u8 *qc;
+
+ if (info->control.flags & IEEE80211_TX_CTRL_AMSDU)
+ return true;
+
+ if (skb_headroom(skb) < sizeof(amsdu_hdr) || skb_tailroom(skb) < 3) {
+ I802_DEBUG_INC(local->tx_expand_skb_head);
+
+ if (pskb_expand_head(skb, sizeof(amsdu_hdr), 3, GFP_ATOMIC)) {
+ wiphy_debug(local->hw.wiphy,
+ "failed to reallocate TX buffer\n");
+ return false;
+ }
+ }
+
+ subframe_len += ieee80211_amsdu_pad(skb, subframe_len);
+
+ amsdu_hdr.h_proto = cpu_to_be16(subframe_len);
+ memcpy(amsdu_hdr.h_source, skb->data + fast_tx->sa_offs, ETH_ALEN);
+ memcpy(amsdu_hdr.h_dest, skb->data + fast_tx->da_offs, ETH_ALEN);
+
+ data = skb_push(skb, sizeof(amsdu_hdr));
+ memmove(data, data + sizeof(amsdu_hdr), hdr_len);
+ memcpy(data + hdr_len, &amsdu_hdr, sizeof(amsdu_hdr));
+
+ hdr = data;
+ qc = ieee80211_get_qos_ctl(hdr);
+ *qc |= IEEE80211_QOS_CTL_A_MSDU_PRESENT;
+
+ info->control.flags |= IEEE80211_TX_CTRL_AMSDU;
+
+ return true;
+}
+
+static bool ieee80211_amsdu_aggregate(struct ieee80211_sub_if_data *sdata,
+ struct sta_info *sta,
+ struct ieee80211_fast_tx *fast_tx,
+ struct sk_buff *skb)
+{
+ struct ieee80211_local *local = sdata->local;
+ u8 tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK;
+ struct ieee80211_txq *txq = sta->sta.txq[tid];
+ struct txq_info *txqi;
+ struct sk_buff **frag_tail, *head;
+ int subframe_len = skb->len - ETH_ALEN;
+ int max_amsdu_len;
+ __be16 len;
+ void *data;
+ bool ret = false;
+ int n = 1;
+
+ if (!ieee80211_hw_check(&local->hw, TX_AMSDU))
+ return false;
+
+ if (!txq)
+ return false;
+
+ txqi = to_txq_info(txq);
+ if (test_bit(IEEE80211_TXQ_NO_AMSDU, &txqi->flags))
+ return false;
+
+ /*
+ * A-MPDU limits maximum MPDU size to 4095 bytes. Since aggregation
+ * sessions are started/stopped without txq flush, use the limit here
+ * to avoid having to de-aggregate later.
+ */
+ max_amsdu_len = min_t(int, sta->sta.max_amsdu_len, 4095);
+
+ spin_lock_bh(&txqi->queue.lock);
+
+ head = skb_peek_tail(&txqi->queue);
+ if (!head)
+ goto out;
+
+ if (skb->len + head->len > max_amsdu_len)
+ goto out;
+
+ if (!ieee80211_amsdu_prepare_head(sdata, fast_tx, head))
+ goto out;
+
+ frag_tail = &skb_shinfo(head)->frag_list;
+ while (*frag_tail) {
+ frag_tail = &(*frag_tail)->next;
+ n++;
+ }
+
+ if (local->hw.max_tx_amsdu_subframes &&
+ n > local->hw.max_tx_amsdu_subframes)
+ goto out;
+
+ if (skb_headroom(skb) < 8 || skb_tailroom(skb) < 3) {
+ I802_DEBUG_INC(local->tx_expand_skb_head);
+
+ if (pskb_expand_head(skb, 8, 3, GFP_ATOMIC)) {
+ wiphy_debug(local->hw.wiphy,
+ "failed to reallocate TX buffer\n");
+ goto out;
+ }
+ }
+
+ subframe_len += ieee80211_amsdu_pad(skb, subframe_len);
+
+ ret = true;
+ data = skb_push(skb, ETH_ALEN + 2);
+ memmove(data, data + ETH_ALEN + 2, 2 * ETH_ALEN);
+
+ data += 2 * ETH_ALEN;
+ len = cpu_to_be16(subframe_len);
+ memcpy(data, &len, 2);
+ memcpy(data + 2, rfc1042_header, ETH_ALEN);
+
+ head->len += skb->len;
+ head->data_len += skb->len;
+ *frag_tail = skb;
+
+out:
+ spin_unlock_bh(&txqi->queue.lock);
+
+ return ret;
+}
+
static bool ieee80211_xmit_fast(struct ieee80211_sub_if_data *sdata,
struct net_device *dev, struct sta_info *sta,
struct ieee80211_fast_tx *fast_tx,
@@ -2811,6 +2958,10 @@ static bool ieee80211_xmit_fast(struct i
ieee80211_tx_stats(dev, skb->len + extra_head);
+ if ((hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_QOS_DATA)) &&
+ ieee80211_amsdu_aggregate(sdata, sta, fast_tx, skb))
+ return true;
+
/* will not be crypto-handled beyond what we do here, so use false
* as the may-encrypt argument for the resize to not account for
* more room than we already have in 'extra_head'
|
