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         tx_header = (void *)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 =
  73                 le16_to_cpu(*(__le16 *) ((u8 *)skb_src->data + dt_offset));
  74         dt_offset += sizeof(u16);
  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         memcpy(skb_put(skb_aggr, skb_src->len), 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
 104         skb_push(skb, sizeof(*local_tx_pd));
 105
 106         local_tx_pd = (struct txpd *) skb->data;
 107         memset(local_tx_pd, 0, sizeof(struct txpd));
 108
 109         /* Original priority has been overwritten */
 110         local_tx_pd->priority = (u8) skb->priority;
 111         local_tx_pd->pkt_delay_2ms =
 112                 mwifiex_wmm_compute_drv_pkt_delay(priv, skb);
 113         local_tx_pd->bss_num = priv->bss_num;
 114         local_tx_pd->bss_type = priv->bss_type;
 115         /* Always zero as the data is followed by struct txpd */
 116         local_tx_pd->tx_pkt_offset = cpu_to_le16(sizeof(struct txpd));
 117         local_tx_pd->tx_pkt_type = cpu_to_le16(PKT_TYPE_AMSDU);
 118         local_tx_pd->tx_pkt_length = cpu_to_le16(skb->len -
 119                                                  sizeof(*local_tx_pd));
 120
 121         if (local_tx_pd->tx_control == 0)
 122                 /* TxCtrl set by user or default */
 123                 local_tx_pd->tx_control = cpu_to_le32(priv->pkt_tx_ctrl);
 124
 125         if (GET_BSS_ROLE(priv) == MWIFIEX_BSS_ROLE_STA &&
 126             priv->adapter->pps_uapsd_mode) {
 127                 if (true == mwifiex_check_last_packet_indication(priv)) {
 128                         priv->adapter->tx_lock_flag = true;
 129                         local_tx_pd->flags =
 130                                 MWIFIEX_TxPD_POWER_MGMT_LAST_PACKET;
 131                 }
 132         }
 133 }
 134
 135 /*
 136  * Create aggregated packet.
 137  *
 138  * This function creates an aggregated MSDU packet, by combining buffers
 139  * from the RA list. Each individual buffer is encapsulated as an AMSDU
 140  * subframe and all such subframes are concatenated together to form the
 141  * AMSDU packet.
 142  *
 143  * A TxPD is also added to the front of the resultant AMSDU packets for
 144  * transmission. The resultant packets format is -
 145  *
 146  * +---- ~ ----+------ ~ ------+------ ~ ------+-..-+------ ~ ------+
 147  * |    TxPD   |AMSDU sub-frame|AMSDU sub-frame| .. |AMSDU sub-frame|
 148  * |           |       1       |       2       | .. |       n       |
 149  * +---- ~ ----+------ ~ ------+------ ~ ------+ .. +------ ~ ------+
 150  */
 151 int
 152 mwifiex_11n_aggregate_pkt(struct mwifiex_private *priv,
 153                           struct mwifiex_ra_list_tbl *pra_list,
 154                           int ptrindex, unsigned long ra_list_flags)
 155                           __releases(&priv->wmm.ra_list_spinlock)
 156 {
 157         struct mwifiex_adapter *adapter = priv->adapter;
 158         struct sk_buff *skb_aggr, *skb_src;
 159         struct mwifiex_txinfo *tx_info_aggr, *tx_info_src;
 160         int pad = 0, ret;
 161         struct mwifiex_tx_param tx_param;
 162         struct txpd *ptx_pd = NULL;
 163         int headroom = adapter->iface_type == MWIFIEX_USB ? 0 : INTF_HEADER_LEN;
 164
 165         skb_src = skb_peek(&pra_list->skb_head);
 166         if (!skb_src) {
 167                 spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
 168                                        ra_list_flags);
 169                 return 0;
 170         }
 171
 172         tx_info_src = MWIFIEX_SKB_TXCB(skb_src);
 173         skb_aggr = dev_alloc_skb(adapter->tx_buf_size);
 174         if (!skb_aggr) {
 175                 dev_err(adapter->dev, "%s: alloc skb_aggr\n", __func__);
 176                 spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
 177                                        ra_list_flags);
 178                 return -1;
 179         }
 180         skb_reserve(skb_aggr, headroom + sizeof(struct txpd));
 181         tx_info_aggr =  MWIFIEX_SKB_TXCB(skb_aggr);
 182
 183         tx_info_aggr->bss_type = tx_info_src->bss_type;
 184         tx_info_aggr->bss_num = tx_info_src->bss_num;
 185         skb_aggr->priority = skb_src->priority;
 186
 187         do {
 188                 /* Check if AMSDU can accommodate this MSDU */
 189                 if (skb_tailroom(skb_aggr) < (skb_src->len + LLC_SNAP_LEN))
 190                         break;
 191
 192                 skb_src = skb_dequeue(&pra_list->skb_head);
 193
 194                 pra_list->total_pkt_count--;
 195
 196                 atomic_dec(&priv->wmm.tx_pkts_queued);
 197
 198                 spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
 199                                        ra_list_flags);
 200                 mwifiex_11n_form_amsdu_pkt(skb_aggr, skb_src, &pad);
 201
 202                 mwifiex_write_data_complete(adapter, skb_src, 0, 0);
 203
 204                 spin_lock_irqsave(&priv->wmm.ra_list_spinlock, ra_list_flags);
 205
 206                 if (!mwifiex_is_ralist_valid(priv, pra_list, ptrindex)) {
 207                         spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
 208                                                ra_list_flags);
 209                         return -1;
 210                 }
 211
 212                 if (skb_tailroom(skb_aggr) < pad) {
 213                         pad = 0;
 214                         break;
 215                 }
 216                 skb_put(skb_aggr, pad);
 217
 218                 skb_src = skb_peek(&pra_list->skb_head);
 219
 220         } while (skb_src);
 221
 222         spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock, ra_list_flags);
 223
 224         /* Last AMSDU packet does not need padding */
 225         skb_trim(skb_aggr, skb_aggr->len - pad);
 226
 227         /* Form AMSDU */
 228         mwifiex_11n_form_amsdu_txpd(priv, skb_aggr);
 229         if (GET_BSS_ROLE(priv) == MWIFIEX_BSS_ROLE_STA)
 230                 ptx_pd = (struct txpd *)skb_aggr->data;
 231
 232         skb_push(skb_aggr, headroom);
 233
 234         if (adapter->iface_type == MWIFIEX_USB) {
 235                 adapter->data_sent = true;
 236                 ret = adapter->if_ops.host_to_card(adapter, MWIFIEX_USB_EP_DATA,
 237                                                    skb_aggr, NULL);
 238         } else {
 239                 /*
 240                  * Padding per MSDU will affect the length of next
 241                  * packet and hence the exact length of next packet
 242                  * is uncertain here.
 243                  *
 244                  * Also, aggregation of transmission buffer, while
 245                  * downloading the data to the card, wont gain much
 246                  * on the AMSDU packets as the AMSDU packets utilizes
 247                  * the transmission buffer space to the maximum
 248                  * (adapter->tx_buf_size).
 249                  */
 250                 tx_param.next_pkt_len = 0;
 251
 252                 ret = adapter->if_ops.host_to_card(adapter, MWIFIEX_TYPE_DATA,
 253                                                    skb_aggr, &tx_param);
 254         }
 255         switch (ret) {
 256         case -EBUSY:
 257                 spin_lock_irqsave(&priv->wmm.ra_list_spinlock, ra_list_flags);
 258                 if (!mwifiex_is_ralist_valid(priv, pra_list, ptrindex)) {
 259                         spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
 260                                                ra_list_flags);
 261                         mwifiex_write_data_complete(adapter, skb_aggr, 1, -1);
 262                         return -1;
 263                 }
 264                 if (GET_BSS_ROLE(priv) == MWIFIEX_BSS_ROLE_STA &&
 265                     adapter->pps_uapsd_mode && adapter->tx_lock_flag) {
 266                                 priv->adapter->tx_lock_flag = false;
 267                                 if (ptx_pd)
 268                                         ptx_pd->flags = 0;
 269                 }
 270
 271                 skb_queue_tail(&pra_list->skb_head, skb_aggr);
 272
 273                 pra_list->total_pkt_count++;
 274
 275                 atomic_inc(&priv->wmm.tx_pkts_queued);
 276
 277                 tx_info_aggr->flags |= MWIFIEX_BUF_FLAG_REQUEUED_PKT;
 278                 spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
 279                                        ra_list_flags);
 280                 dev_dbg(adapter->dev, "data: -EBUSY is returned\n");
 281                 break;
 282         case -1:
 283                 if (adapter->iface_type != MWIFIEX_PCIE)
 284                         adapter->data_sent = false;
 285                 dev_err(adapter->dev, "%s: host_to_card failed: %#x\n",
 286                         __func__, ret);
 287                 adapter->dbg.num_tx_host_to_card_failure++;
 288                 mwifiex_write_data_complete(adapter, skb_aggr, 1, ret);
 289                 return 0;
 290         case -EINPROGRESS:
 291                 if (adapter->iface_type != MWIFIEX_PCIE)
 292                         adapter->data_sent = false;
 293                 break;
 294         case 0:
 295                 mwifiex_write_data_complete(adapter, skb_aggr, 1, ret);
 296                 break;
 297         default:
 298                 break;
 299         }
 300         if (ret != -EBUSY) {
 301                 mwifiex_rotate_priolists(priv, pra_list, ptrindex);
 302         }
 303
 304         return 0;
 305 }