drivers/net/wireless/mwifiex/11n_aggr.c

   1 /*
   2  * Marvell Wireless LAN device driver: 802.11n Aggregation
   3  *
   4  * Copyright (C) 2011, 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         skb_put(skb_aggr, sizeof(*tx_header));
  66
  67         tx_header = (struct tx_packet_hdr *) skb_aggr->data;
  68
  69         /* Copy DA and SA */
  70         dt_offset = 2 * ETH_ALEN;
  71         memcpy(&tx_header->eth803_hdr, skb_src->data, dt_offset);
  72
  73         /* Copy SNAP header */
  74         snap.snap_type = *(u16 *) ((u8 *)skb_src->data + dt_offset);
  75         dt_offset += sizeof(u16);
  76
  77         memcpy(&tx_header->rfc1042_hdr, &snap, sizeof(struct rfc_1042_hdr));
  78
  79         skb_pull(skb_src, dt_offset);
  80
  81         /* Update Length field */
  82         tx_header->eth803_hdr.h_proto = htons(skb_src->len + LLC_SNAP_LEN);
  83
  84         /* Add payload */
  85         skb_put(skb_aggr, skb_src->len);
  86         memcpy(skb_aggr->data + sizeof(*tx_header), skb_src->data,
  87                                                         skb_src->len);
  88         *pad = (((skb_src->len + LLC_SNAP_LEN) & 3)) ? (4 - (((skb_src->len +
  89                                                       LLC_SNAP_LEN)) & 3)) : 0;
  90         skb_put(skb_aggr, *pad);
  91
  92         return skb_aggr->len + *pad;
  93 }
  94
  95 /*
  96  * Adds TxPD to AMSDU header.
  97  *
  98  * Each AMSDU packet will contain one TxPD at the beginning,
  99  * followed by multiple AMSDU subframes.
 100  */
 101 static void
 102 mwifiex_11n_form_amsdu_txpd(struct mwifiex_private *priv,
 103                             struct sk_buff *skb)
 104 {
 105         struct txpd *local_tx_pd;
 106
 107         skb_push(skb, sizeof(*local_tx_pd));
 108
 109         local_tx_pd = (struct txpd *) skb->data;
 110         memset(local_tx_pd, 0, sizeof(struct txpd));
 111
 112         /* Original priority has been overwritten */
 113         local_tx_pd->priority = (u8) skb->priority;
 114         local_tx_pd->pkt_delay_2ms =
 115                 mwifiex_wmm_compute_drv_pkt_delay(priv, skb);
 116         local_tx_pd->bss_num = priv->bss_num;
 117         local_tx_pd->bss_type = priv->bss_type;
 118         /* Always zero as the data is followed by struct txpd */
 119         local_tx_pd->tx_pkt_offset = cpu_to_le16(sizeof(struct txpd));
 120         local_tx_pd->tx_pkt_type = cpu_to_le16(PKT_TYPE_AMSDU);
 121         local_tx_pd->tx_pkt_length = cpu_to_le16(skb->len -
 122                         sizeof(*local_tx_pd));
 123
 124         if (local_tx_pd->tx_control == 0)
 125                 /* TxCtrl set by user or default */
 126                 local_tx_pd->tx_control = cpu_to_le32(priv->pkt_tx_ctrl);
 127
 128         if ((GET_BSS_ROLE(priv) == MWIFIEX_BSS_ROLE_STA) &&
 129                 (priv->adapter->pps_uapsd_mode)) {
 130                 if (true == mwifiex_check_last_packet_indication(priv)) {
 131                         priv->adapter->tx_lock_flag = true;
 132                         local_tx_pd->flags =
 133                                 MWIFIEX_TxPD_POWER_MGMT_LAST_PACKET;
 134                 }
 135         }
 136 }
 137
 138 /*
 139  * Create aggregated packet.
 140  *
 141  * This function creates an aggregated MSDU packet, by combining buffers
 142  * from the RA list. Each individual buffer is encapsulated as an AMSDU
 143  * subframe and all such subframes are concatenated together to form the
 144  * AMSDU packet.
 145  *
 146  * A TxPD is also added to the front of the resultant AMSDU packets for
 147  * transmission. The resultant packets format is -
 148  *
 149  * +---- ~ ----+------ ~ ------+------ ~ ------+-..-+------ ~ ------+
 150  * |    TxPD   |AMSDU sub-frame|AMSDU sub-frame| .. |AMSDU sub-frame|
 151  * |           |       1       |       2       | .. |       n       |
 152  * +---- ~ ----+------ ~ ------+------ ~ ------+ .. +------ ~ ------+
 153  */
 154 int
 155 mwifiex_11n_aggregate_pkt(struct mwifiex_private *priv,
 156                           struct mwifiex_ra_list_tbl *pra_list, int headroom,
 157                           int ptrindex, unsigned long ra_list_flags)
 158                           __releases(&priv->wmm.ra_list_spinlock)
 159 {
 160         struct mwifiex_adapter *adapter = priv->adapter;
 161         struct sk_buff *skb_aggr, *skb_src;
 162         struct mwifiex_txinfo *tx_info_aggr, *tx_info_src;
 163         int pad = 0, ret;
 164         struct mwifiex_tx_param tx_param;
 165         struct txpd *ptx_pd = NULL;
 166
 167         skb_src = skb_peek(&pra_list->skb_head);
 168         if (!skb_src) {
 169                 spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
 170                                        ra_list_flags);
 171                 return 0;
 172         }
 173
 174         tx_info_src = MWIFIEX_SKB_TXCB(skb_src);
 175         skb_aggr = dev_alloc_skb(adapter->tx_buf_size);
 176         if (!skb_aggr) {
 177                 dev_err(adapter->dev, "%s: alloc skb_aggr\n", __func__);
 178                 spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
 179                                        ra_list_flags);
 180                 return -1;
 181         }
 182         skb_reserve(skb_aggr, headroom + sizeof(struct txpd));
 183         tx_info_aggr =  MWIFIEX_SKB_TXCB(skb_aggr);
 184
 185         tx_info_aggr->bss_index = tx_info_src->bss_index;
 186         skb_aggr->priority = skb_src->priority;
 187
 188         do {
 189                 /* Check if AMSDU can accommodate this MSDU */
 190                 if (skb_tailroom(skb_aggr) < (skb_src->len + LLC_SNAP_LEN))
 191                         break;
 192
 193                 skb_src = skb_dequeue(&pra_list->skb_head);
 194
 195                 pra_list->total_pkts_size -= skb_src->len;
 196
 197                 atomic_dec(&priv->wmm.tx_pkts_queued);
 198
 199                 spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
 200                                        ra_list_flags);
 201                 mwifiex_11n_form_amsdu_pkt(skb_aggr, skb_src, &pad);
 202
 203                 mwifiex_write_data_complete(adapter, skb_src, 0);
 204
 205                 spin_lock_irqsave(&priv->wmm.ra_list_spinlock, ra_list_flags);
 206
 207                 if (!mwifiex_is_ralist_valid(priv, pra_list, ptrindex)) {
 208                         spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
 209                                                ra_list_flags);
 210                         return -1;
 211                 }
 212
 213                 if (skb_tailroom(skb_aggr) < pad) {
 214                         pad = 0;
 215                         break;
 216                 }
 217                 skb_put(skb_aggr, pad);
 218
 219                 skb_src = skb_peek(&pra_list->skb_head);
 220
 221         } while (skb_src);
 222
 223         spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock, ra_list_flags);
 224
 225         /* Last AMSDU packet does not need padding */
 226         skb_trim(skb_aggr, skb_aggr->len - pad);
 227
 228         /* Form AMSDU */
 229         mwifiex_11n_form_amsdu_txpd(priv, skb_aggr);
 230         if (GET_BSS_ROLE(priv) == MWIFIEX_BSS_ROLE_STA)
 231                 ptx_pd = (struct txpd *)skb_aggr->data;
 232
 233         skb_push(skb_aggr, headroom);
 234
 235         /*
 236          * Padding per MSDU will affect the length of next
 237          * packet and hence the exact length of next packet
 238          * is uncertain here.
 239          *
 240          * Also, aggregation of transmission buffer, while
 241          * downloading the data to the card, wont gain much
 242          * on the AMSDU packets as the AMSDU packets utilizes
 243          * the transmission buffer space to the maximum
 244          * (adapter->tx_buf_size).
 245          */
 246         tx_param.next_pkt_len = 0;
 247
 248         ret = adapter->if_ops.host_to_card(adapter, MWIFIEX_TYPE_DATA,
 249                                            skb_aggr, &tx_param);
 250         switch (ret) {
 251         case -EBUSY:
 252                 spin_lock_irqsave(&priv->wmm.ra_list_spinlock, ra_list_flags);
 253                 if (!mwifiex_is_ralist_valid(priv, pra_list, ptrindex)) {
 254                         spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
 255                                                ra_list_flags);
 256                         mwifiex_write_data_complete(adapter, skb_aggr, -1);
 257                         return -1;
 258                 }
 259                 if ((GET_BSS_ROLE(priv) == MWIFIEX_BSS_ROLE_STA) &&
 260                         (adapter->pps_uapsd_mode) &&
 261                         (adapter->tx_lock_flag)) {
 262                                 priv->adapter->tx_lock_flag = false;
 263                                 if (ptx_pd)
 264                                         ptx_pd->flags = 0;
 265                 }
 266
 267                 skb_queue_tail(&pra_list->skb_head, skb_aggr);
 268
 269                 pra_list->total_pkts_size += skb_aggr->len;
 270
 271                 atomic_inc(&priv->wmm.tx_pkts_queued);
 272
 273                 tx_info_aggr->flags |= MWIFIEX_BUF_FLAG_REQUEUED_PKT;
 274                 spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
 275                                        ra_list_flags);
 276                 dev_dbg(adapter->dev, "data: -EBUSY is returned\n");
 277                 break;
 278         case -1:
 279                 adapter->data_sent = false;
 280                 dev_err(adapter->dev, "%s: host_to_card failed: %#x\n",
 281                                                 __func__, ret);
 282                 adapter->dbg.num_tx_host_to_card_failure++;
 283                 mwifiex_write_data_complete(adapter, skb_aggr, ret);
 284                 return 0;
 285         case -EINPROGRESS:
 286                 adapter->data_sent = false;
 287                 break;
 288         case 0:
 289                 mwifiex_write_data_complete(adapter, skb_aggr, ret);
 290                 break;
 291         default:
 292                 break;
 293         }
 294         if (ret != -EBUSY) {
 295                 spin_lock_irqsave(&priv->wmm.ra_list_spinlock, ra_list_flags);
 296                 if (mwifiex_is_ralist_valid(priv, pra_list, ptrindex)) {
 297                         priv->wmm.packets_out[ptrindex]++;
 298                         priv->wmm.tid_tbl_ptr[ptrindex].ra_list_curr = pra_list;
 299                 }
 300                 /* Now bss_prio_cur pointer points to next node */
 301                 adapter->bss_prio_tbl[priv->bss_priority].bss_prio_cur =
 302                         list_first_entry(
 303                                 &adapter->bss_prio_tbl[priv->bss_priority]
 304                                 .bss_prio_cur->list,
 305                                 struct mwifiex_bss_prio_node, list);
 306                 spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
 307                                        ra_list_flags);
 308         }
 309
 310         return 0;
 311 }