1 /*
2  * Marvell Wireless LAN device driver: 802.11n Aggregation
3  *
4  * Copyright (C) 2011-2014, Marvell International Ltd.
5  *
6  * This software file (the "File") is distributed by Marvell International
7  * Ltd. under the terms of the GNU General Public License Version 2, June 1991
8  * (the "License").  You may use, redistribute and/or modify this File in
9  * accordance with the terms and conditions of the License, a copy of which
10  * is available by writing to the Free Software Foundation, Inc.,
11  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA or on the
12  * worldwide web at http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt.
13  *
14  * THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
16  * ARE EXPRESSLY DISCLAIMED.  The License provides additional details about
17  * this warranty disclaimer.
18  */
19 
20 #include "decl.h"
21 #include "ioctl.h"
22 #include "util.h"
23 #include "fw.h"
24 #include "main.h"
25 #include "wmm.h"
26 #include "11n.h"
27 #include "11n_aggr.h"
28 
29 /*
30  * Creates an AMSDU subframe for aggregation into one AMSDU packet.
31  *
32  * The resultant AMSDU subframe format is -
33  *
34  * +---- ~ -----+---- ~ ------+---- ~ -----+----- ~ -----+---- ~ -----+
35  * |     DA     |     SA      |   Length   | SNAP header |   MSDU     |
36  * | data[0..5] | data[6..11] |            |             | data[14..] |
37  * +---- ~ -----+---- ~ ------+---- ~ -----+----- ~ -----+---- ~ -----+
38  * <--6-bytes--> <--6-bytes--> <--2-bytes--><--8-bytes--> <--n-bytes-->
39  *
40  * This function also computes the amount of padding required to make the
41  * buffer length multiple of 4 bytes.
42  *
43  * Data => |DA|SA|SNAP-TYPE|........    .|
44  * MSDU => |DA|SA|Length|SNAP|......   ..|
45  */
46 static int
47 mwifiex_11n_form_amsdu_pkt(struct sk_buff *skb_aggr,
48 			   struct sk_buff *skb_src, int *pad)
49 
50 {
51 	int dt_offset;
52 	struct rfc_1042_hdr snap = {
53 		0xaa,		/* LLC DSAP */
54 		0xaa,		/* LLC SSAP */
55 		0x03,		/* LLC CTRL */
56 		{0x00, 0x00, 0x00},	/* SNAP OUI */
57 		0x0000		/* SNAP type */
58 			/*
59 			 * This field will be overwritten
60 			 * later with ethertype
61 			 */
62 	};
63 	struct tx_packet_hdr *tx_header;
64 
65 	tx_header = skb_put(skb_aggr, sizeof(*tx_header));
66 
67 	/* Copy DA and SA */
68 	dt_offset = 2 * ETH_ALEN;
69 	memcpy(&tx_header->eth803_hdr, skb_src->data, dt_offset);
70 
71 	/* Copy SNAP header */
72 	snap.snap_type = ((struct ethhdr *)skb_src->data)->h_proto;
73 
74 	dt_offset += sizeof(__be16);
75 
76 	memcpy(&tx_header->rfc1042_hdr, &snap, sizeof(struct rfc_1042_hdr));
77 
78 	skb_pull(skb_src, dt_offset);
79 
80 	/* Update Length field */
81 	tx_header->eth803_hdr.h_proto = htons(skb_src->len + LLC_SNAP_LEN);
82 
83 	/* Add payload */
84 	skb_put_data(skb_aggr, skb_src->data, skb_src->len);
85 
86 	/* Add padding for new MSDU to start from 4 byte boundary */
87 	*pad = (4 - ((unsigned long)skb_aggr->tail & 0x3)) % 4;
88 
89 	return skb_aggr->len + *pad;
90 }
91 
92 /*
93  * Adds TxPD to AMSDU header.
94  *
95  * Each AMSDU packet will contain one TxPD at the beginning,
96  * followed by multiple AMSDU subframes.
97  */
98 static void
99 mwifiex_11n_form_amsdu_txpd(struct mwifiex_private *priv,
100 			    struct sk_buff *skb)
101 {
102 	struct txpd *local_tx_pd;
103 	struct mwifiex_txinfo *tx_info = MWIFIEX_SKB_TXCB(skb);
104 
105 	skb_push(skb, sizeof(*local_tx_pd));
106 
107 	local_tx_pd = (struct txpd *) skb->data;
108 	memset(local_tx_pd, 0, sizeof(struct txpd));
109 
110 	/* Original priority has been overwritten */
111 	local_tx_pd->priority = (u8) skb->priority;
112 	local_tx_pd->pkt_delay_2ms =
113 		mwifiex_wmm_compute_drv_pkt_delay(priv, skb);
114 	local_tx_pd->bss_num = priv->bss_num;
115 	local_tx_pd->bss_type = priv->bss_type;
116 	/* Always zero as the data is followed by struct txpd */
117 	local_tx_pd->tx_pkt_offset = cpu_to_le16(sizeof(struct txpd));
118 	local_tx_pd->tx_pkt_type = cpu_to_le16(PKT_TYPE_AMSDU);
119 	local_tx_pd->tx_pkt_length = cpu_to_le16(skb->len -
120 						 sizeof(*local_tx_pd));
121 
122 	if (tx_info->flags & MWIFIEX_BUF_FLAG_TDLS_PKT)
123 		local_tx_pd->flags |= MWIFIEX_TXPD_FLAGS_TDLS_PACKET;
124 
125 	if (local_tx_pd->tx_control == 0)
126 		/* TxCtrl set by user or default */
127 		local_tx_pd->tx_control = cpu_to_le32(priv->pkt_tx_ctrl);
128 
129 	if (GET_BSS_ROLE(priv) == MWIFIEX_BSS_ROLE_STA &&
130 	    priv->adapter->pps_uapsd_mode) {
131 		if (true == mwifiex_check_last_packet_indication(priv)) {
132 			priv->adapter->tx_lock_flag = true;
133 			local_tx_pd->flags =
134 				MWIFIEX_TxPD_POWER_MGMT_LAST_PACKET;
135 		}
136 	}
137 }
138 
139 /*
140  * Create aggregated packet.
141  *
142  * This function creates an aggregated MSDU packet, by combining buffers
143  * from the RA list. Each individual buffer is encapsulated as an AMSDU
144  * subframe and all such subframes are concatenated together to form the
145  * AMSDU packet.
146  *
147  * A TxPD is also added to the front of the resultant AMSDU packets for
148  * transmission. The resultant packets format is -
149  *
150  * +---- ~ ----+------ ~ ------+------ ~ ------+-..-+------ ~ ------+
151  * |    TxPD   |AMSDU sub-frame|AMSDU sub-frame| .. |AMSDU sub-frame|
152  * |           |       1       |       2       | .. |       n       |
153  * +---- ~ ----+------ ~ ------+------ ~ ------+ .. +------ ~ ------+
154  */
155 int
156 mwifiex_11n_aggregate_pkt(struct mwifiex_private *priv,
157 			  struct mwifiex_ra_list_tbl *pra_list,
158 			  int ptrindex, unsigned long ra_list_flags)
159 			  __releases(&priv->wmm.ra_list_spinlock)
160 {
161 	struct mwifiex_adapter *adapter = priv->adapter;
162 	struct sk_buff *skb_aggr, *skb_src;
163 	struct mwifiex_txinfo *tx_info_aggr, *tx_info_src;
164 	int pad = 0, aggr_num = 0, ret;
165 	struct mwifiex_tx_param tx_param;
166 	struct txpd *ptx_pd = NULL;
167 	int headroom = adapter->intf_hdr_len;
168 
169 	skb_src = skb_peek(&pra_list->skb_head);
170 	if (!skb_src) {
171 		spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
172 				       ra_list_flags);
173 		return 0;
174 	}
175 
176 	tx_info_src = MWIFIEX_SKB_TXCB(skb_src);
177 	skb_aggr = mwifiex_alloc_dma_align_buf(adapter->tx_buf_size,
178 					       GFP_ATOMIC);
179 	if (!skb_aggr) {
180 		spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
181 				       ra_list_flags);
182 		return -1;
183 	}
184 
185 	/* skb_aggr->data already 64 byte align, just reserve bus interface
186 	 * header and txpd.
187 	 */
188 	skb_reserve(skb_aggr, headroom + sizeof(struct txpd));
189 	tx_info_aggr =  MWIFIEX_SKB_TXCB(skb_aggr);
190 
191 	memset(tx_info_aggr, 0, sizeof(*tx_info_aggr));
192 	tx_info_aggr->bss_type = tx_info_src->bss_type;
193 	tx_info_aggr->bss_num = tx_info_src->bss_num;
194 
195 	if (tx_info_src->flags & MWIFIEX_BUF_FLAG_TDLS_PKT)
196 		tx_info_aggr->flags |= MWIFIEX_BUF_FLAG_TDLS_PKT;
197 	tx_info_aggr->flags |= MWIFIEX_BUF_FLAG_AGGR_PKT;
198 	skb_aggr->priority = skb_src->priority;
199 	skb_aggr->tstamp = skb_src->tstamp;
200 
201 	do {
202 		/* Check if AMSDU can accommodate this MSDU */
203 		if ((skb_aggr->len + skb_src->len + LLC_SNAP_LEN) >
204 		    adapter->tx_buf_size)
205 			break;
206 
207 		skb_src = skb_dequeue(&pra_list->skb_head);
208 		pra_list->total_pkt_count--;
209 		atomic_dec(&priv->wmm.tx_pkts_queued);
210 		aggr_num++;
211 		spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
212 				       ra_list_flags);
213 		mwifiex_11n_form_amsdu_pkt(skb_aggr, skb_src, &pad);
214 
215 		mwifiex_write_data_complete(adapter, skb_src, 0, 0);
216 
217 		spin_lock_irqsave(&priv->wmm.ra_list_spinlock, ra_list_flags);
218 
219 		if (!mwifiex_is_ralist_valid(priv, pra_list, ptrindex)) {
220 			spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
221 					       ra_list_flags);
222 			return -1;
223 		}
224 
225 		if (skb_tailroom(skb_aggr) < pad) {
226 			pad = 0;
227 			break;
228 		}
229 		skb_put(skb_aggr, pad);
230 
231 		skb_src = skb_peek(&pra_list->skb_head);
232 
233 	} while (skb_src);
234 
235 	spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock, ra_list_flags);
236 
237 	/* Last AMSDU packet does not need padding */
238 	skb_trim(skb_aggr, skb_aggr->len - pad);
239 
240 	/* Form AMSDU */
241 	mwifiex_11n_form_amsdu_txpd(priv, skb_aggr);
242 	if (GET_BSS_ROLE(priv) == MWIFIEX_BSS_ROLE_STA)
243 		ptx_pd = (struct txpd *)skb_aggr->data;
244 
245 	skb_push(skb_aggr, headroom);
246 	tx_info_aggr->aggr_num = aggr_num * 2;
247 	if (adapter->data_sent || adapter->tx_lock_flag) {
248 		atomic_add(aggr_num * 2, &adapter->tx_queued);
249 		skb_queue_tail(&adapter->tx_data_q, skb_aggr);
250 		return 0;
251 	}
252 
253 	if (skb_src)
254 		tx_param.next_pkt_len = skb_src->len + sizeof(struct txpd);
255 	else
256 		tx_param.next_pkt_len = 0;
257 
258 	if (adapter->iface_type == MWIFIEX_USB) {
259 		ret = adapter->if_ops.host_to_card(adapter, priv->usb_port,
260 						   skb_aggr, &tx_param);
261 	} else {
262 
263 		ret = adapter->if_ops.host_to_card(adapter, MWIFIEX_TYPE_DATA,
264 						   skb_aggr, &tx_param);
265 	}
266 	switch (ret) {
267 	case -EBUSY:
268 		spin_lock_irqsave(&priv->wmm.ra_list_spinlock, ra_list_flags);
269 		if (!mwifiex_is_ralist_valid(priv, pra_list, ptrindex)) {
270 			spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
271 					       ra_list_flags);
272 			mwifiex_write_data_complete(adapter, skb_aggr, 1, -1);
273 			return -1;
274 		}
275 		if (GET_BSS_ROLE(priv) == MWIFIEX_BSS_ROLE_STA &&
276 		    adapter->pps_uapsd_mode && adapter->tx_lock_flag) {
277 				priv->adapter->tx_lock_flag = false;
278 				if (ptx_pd)
279 					ptx_pd->flags = 0;
280 		}
281 
282 		skb_queue_tail(&pra_list->skb_head, skb_aggr);
283 
284 		pra_list->total_pkt_count++;
285 
286 		atomic_inc(&priv->wmm.tx_pkts_queued);
287 
288 		tx_info_aggr->flags |= MWIFIEX_BUF_FLAG_REQUEUED_PKT;
289 		spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
290 				       ra_list_flags);
291 		mwifiex_dbg(adapter, ERROR, "data: -EBUSY is returned\n");
292 		break;
293 	case -1:
294 		mwifiex_dbg(adapter, ERROR, "%s: host_to_card failed: %#x\n",
295 			    __func__, ret);
296 		adapter->dbg.num_tx_host_to_card_failure++;
297 		mwifiex_write_data_complete(adapter, skb_aggr, 1, ret);
298 		return 0;
299 	case -EINPROGRESS:
300 		break;
301 	case 0:
302 		mwifiex_write_data_complete(adapter, skb_aggr, 1, ret);
303 		break;
304 	default:
305 		break;
306 	}
307 	if (ret != -EBUSY) {
308 		mwifiex_rotate_priolists(priv, pra_list, ptrindex);
309 	}
310 
311 	return 0;
312 }
313