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 = *(u16 *) ((u8 *)skb_src->data + dt_offset);
  73         dt_offset += sizeof(u16);
  74
  75         memcpy(&tx_header->rfc1042_hdr, &snap, sizeof(struct rfc_1042_hdr));
  76
  77         skb_pull(skb_src, dt_offset);
  78
  79         /* Update Length field */
  80         tx_header->eth803_hdr.h_proto = htons(skb_src->len + LLC_SNAP_LEN);
  81
  82         /* Add payload */
  83         memcpy(skb_put(skb_aggr, skb_src->len), skb_src->data, skb_src->len);
  84
  85         /* Add padding for new MSDU to start from 4 byte boundary */
  86         *pad = (4 - ((unsigned long)skb_aggr->tail & 0x3)) % 4;
  87
  88         return skb_aggr->len + *pad;
  89 }
  90
  91 /*
  92  * Adds TxPD to AMSDU header.
  93  *
  94  * Each AMSDU packet will contain one TxPD at the beginning,
  95  * followed by multiple AMSDU subframes.
  96  */
  97 static void
  98 mwifiex_11n_form_amsdu_txpd(struct mwifiex_private *priv,
  99                             struct sk_buff *skb)
 100 {
 101         struct txpd *local_tx_pd;
 102
 103         skb_push(skb, sizeof(*local_tx_pd));
 104
 105         local_tx_pd = (struct txpd *) skb->data;
 106         memset(local_tx_pd, 0, sizeof(struct txpd));
 107
 108         /* Original priority has been overwritten */
 109         local_tx_pd->priority = (u8) skb->priority;
 110         local_tx_pd->pkt_delay_2ms =
 111                 mwifiex_wmm_compute_drv_pkt_delay(priv, skb);
 112         local_tx_pd->bss_num = priv->bss_num;
 113         local_tx_pd->bss_type = priv->bss_type;
 114         /* Always zero as the data is followed by struct txpd */
 115         local_tx_pd->tx_pkt_offset = cpu_to_le16(sizeof(struct txpd));
 116         local_tx_pd->tx_pkt_type = cpu_to_le16(PKT_TYPE_AMSDU);
 117         local_tx_pd->tx_pkt_length = cpu_to_le16(skb->len -
 118                                                  sizeof(*local_tx_pd));
 119
 120         if (local_tx_pd->tx_control == 0)
 121                 /* TxCtrl set by user or default */
 122                 local_tx_pd->tx_control = cpu_to_le32(priv->pkt_tx_ctrl);
 123
 124         if (GET_BSS_ROLE(priv) == MWIFIEX_BSS_ROLE_STA &&
 125             priv->adapter->pps_uapsd_mode) {
 126                 if (true == mwifiex_check_last_packet_indication(priv)) {
 127                         priv->adapter->tx_lock_flag = true;
 128                         local_tx_pd->flags =
 129                                 MWIFIEX_TxPD_POWER_MGMT_LAST_PACKET;
 130                 }
 131         }
 132 }
 133
 134 /*
 135  * Create aggregated packet.
 136  *
 137  * This function creates an aggregated MSDU packet, by combining buffers
 138  * from the RA list. Each individual buffer is encapsulated as an AMSDU
 139  * subframe and all such subframes are concatenated together to form the
 140  * AMSDU packet.
 141  *
 142  * A TxPD is also added to the front of the resultant AMSDU packets for
 143  * transmission. The resultant packets format is -
 144  *
 145  * +---- ~ ----+------ ~ ------+------ ~ ------+-..-+------ ~ ------+
 146  * |    TxPD   |AMSDU sub-frame|AMSDU sub-frame| .. |AMSDU sub-frame|
 147  * |           |       1       |       2       | .. |       n       |
 148  * +---- ~ ----+------ ~ ------+------ ~ ------+ .. +------ ~ ------+
 149  */
 150 int
 151 mwifiex_11n_aggregate_pkt(struct mwifiex_private *priv,
 152                           struct mwifiex_ra_list_tbl *pra_list, int headroom,
 153                           int ptrindex, unsigned long ra_list_flags)
 154                           __releases(&priv->wmm.ra_list_spinlock)
 155 {
 156         struct mwifiex_adapter *adapter = priv->adapter;
 157         struct sk_buff *skb_aggr, *skb_src;
 158         struct mwifiex_txinfo *tx_info_aggr, *tx_info_src;
 159         int pad = 0, ret;
 160         struct mwifiex_tx_param tx_param;
 161         struct txpd *ptx_pd = NULL;
 162
 163         skb_src = skb_peek(&pra_list->skb_head);
 164         if (!skb_src) {
 165                 spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
 166                                        ra_list_flags);
 167                 return 0;
 168         }
 169
 170         tx_info_src = MWIFIEX_SKB_TXCB(skb_src);
 171         skb_aggr = dev_alloc_skb(adapter->tx_buf_size);
 172         if (!skb_aggr) {
 173                 dev_err(adapter->dev, "%s: alloc skb_aggr\n", __func__);
 174                 spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
 175                                        ra_list_flags);
 176                 return -1;
 177         }
 178         skb_reserve(skb_aggr, headroom + sizeof(struct txpd));
 179         tx_info_aggr =  MWIFIEX_SKB_TXCB(skb_aggr);
 180
 181         tx_info_aggr->bss_type = tx_info_src->bss_type;
 182         tx_info_aggr->bss_num = tx_info_src->bss_num;
 183         skb_aggr->priority = skb_src->priority;
 184
 185         do {
 186                 /* Check if AMSDU can accommodate this MSDU */
 187                 if (skb_tailroom(skb_aggr) < (skb_src->len + LLC_SNAP_LEN))
 188                         break;
 189
 190                 skb_src = skb_dequeue(&pra_list->skb_head);
 191
 192                 pra_list->total_pkts_size -= skb_src->len;
 193
 194                 atomic_dec(&priv->wmm.tx_pkts_queued);
 195
 196                 spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
 197                                        ra_list_flags);
 198                 mwifiex_11n_form_amsdu_pkt(skb_aggr, skb_src, &pad);
 199
 200                 mwifiex_write_data_complete(adapter, skb_src, 0, 0);
 201
 202                 spin_lock_irqsave(&priv->wmm.ra_list_spinlock, ra_list_flags);
 203
 204                 if (!mwifiex_is_ralist_valid(priv, pra_list, ptrindex)) {
 205                         spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
 206                                                ra_list_flags);
 207                         return -1;
 208                 }
 209
 210                 if (skb_tailroom(skb_aggr) < pad) {
 211                         pad = 0;
 212                         break;
 213                 }
 214                 skb_put(skb_aggr, pad);
 215
 216                 skb_src = skb_peek(&pra_list->skb_head);
 217
 218         } while (skb_src);
 219
 220         spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock, ra_list_flags);
 221
 222         /* Last AMSDU packet does not need padding */
 223         skb_trim(skb_aggr, skb_aggr->len - pad);
 224
 225         /* Form AMSDU */
 226         mwifiex_11n_form_amsdu_txpd(priv, skb_aggr);
 227         if (GET_BSS_ROLE(priv) == MWIFIEX_BSS_ROLE_STA)
 228                 ptx_pd = (struct txpd *)skb_aggr->data;
 229
 230         skb_push(skb_aggr, headroom);
 231
 232         if (adapter->iface_type == MWIFIEX_USB) {
 233                 adapter->data_sent = true;
 234                 ret = adapter->if_ops.host_to_card(adapter, MWIFIEX_USB_EP_DATA,
 235                                                    skb_aggr, NULL);
 236         } else {
 237                 /*
 238                  * Padding per MSDU will affect the length of next
 239                  * packet and hence the exact length of next packet
 240                  * is uncertain here.
 241                  *
 242                  * Also, aggregation of transmission buffer, while
 243                  * downloading the data to the card, wont gain much
 244                  * on the AMSDU packets as the AMSDU packets utilizes
 245                  * the transmission buffer space to the maximum
 246                  * (adapter->tx_buf_size).
 247                  */
 248                 tx_param.next_pkt_len = 0;
 249
 250                 ret = adapter->if_ops.host_to_card(adapter, MWIFIEX_TYPE_DATA,
 251                                                    skb_aggr, &tx_param);
 252         }
 253         switch (ret) {
 254         case -EBUSY:
 255                 spin_lock_irqsave(&priv->wmm.ra_list_spinlock, ra_list_flags);
 256                 if (!mwifiex_is_ralist_valid(priv, pra_list, ptrindex)) {
 257                         spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
 258                                                ra_list_flags);
 259                         mwifiex_write_data_complete(adapter, skb_aggr, 1, -1);
 260                         return -1;
 261                 }
 262                 if (GET_BSS_ROLE(priv) == MWIFIEX_BSS_ROLE_STA &&
 263                     adapter->pps_uapsd_mode && adapter->tx_lock_flag) {
 264                                 priv->adapter->tx_lock_flag = false;
 265                                 if (ptx_pd)
 266                                         ptx_pd->flags = 0;
 267                 }
 268
 269                 skb_queue_tail(&pra_list->skb_head, skb_aggr);
 270
 271                 pra_list->total_pkts_size += skb_aggr->len;
 272
 273                 atomic_inc(&priv->wmm.tx_pkts_queued);
 274
 275                 tx_info_aggr->flags |= MWIFIEX_BUF_FLAG_REQUEUED_PKT;
 276                 spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
 277                                        ra_list_flags);
 278                 dev_dbg(adapter->dev, "data: -EBUSY is returned\n");
 279                 break;
 280         case -1:
 281                 adapter->data_sent = false;
 282                 dev_err(adapter->dev, "%s: host_to_card failed: %#x\n",
 283                         __func__, ret);
 284                 adapter->dbg.num_tx_host_to_card_failure++;
 285                 mwifiex_write_data_complete(adapter, skb_aggr, 1, ret);
 286                 return 0;
 287         case -EINPROGRESS:
 288                 adapter->data_sent = false;
 289                 break;
 290         case 0:
 291                 mwifiex_write_data_complete(adapter, skb_aggr, 1, ret);
 292                 break;
 293         default:
 294                 break;
 295         }
 296         if (ret != -EBUSY) {
 297                 spin_lock_irqsave(&priv->wmm.ra_list_spinlock, ra_list_flags);
 298                 if (mwifiex_is_ralist_valid(priv, pra_list, ptrindex)) {
 299                         priv->wmm.packets_out[ptrindex]++;
 300                         priv->wmm.tid_tbl_ptr[ptrindex].ra_list_curr = pra_list;
 301                 }
 302                 /* Now bss_prio_cur pointer points to next node */
 303                 adapter->bss_prio_tbl[priv->bss_priority].bss_prio_cur =
 304                         list_first_entry(
 305                                 &adapter->bss_prio_tbl[priv->bss_priority]
 306                                 .bss_prio_cur->list,
 307                                 struct mwifiex_bss_prio_node, list);
 308                 spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock,
 309                                        ra_list_flags);
 310         }
 311
 312         return 0;
 313 }