drivers/net/wireless/mwifiex/uap_txrx.c

   1 /*
   2  * Marvell Wireless LAN device driver: AP TX and RX data handling
   3  *
   4  * Copyright (C) 2012, 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 "main.h"
  23 #include "wmm.h"
  24 #include "11n_aggr.h"
  25 #include "11n_rxreorder.h"
  26
  27 /* This function checks if particular RA list has packets more than low bridge
  28  * packet threshold and then deletes packet from this RA list.
  29  * Function deletes packets from such RA list and returns true. If no such list
  30  * is found, false is returned.
  31  */
  32 static bool
  33 mwifiex_uap_del_tx_pkts_in_ralist(struct mwifiex_private *priv,
  34                                   struct list_head *ra_list_head)
  35 {
  36         struct mwifiex_ra_list_tbl *ra_list;
  37         struct sk_buff *skb, *tmp;
  38         bool pkt_deleted = false;
  39         struct mwifiex_txinfo *tx_info;
  40         struct mwifiex_adapter *adapter = priv->adapter;
  41
  42         list_for_each_entry(ra_list, ra_list_head, list) {
  43                 if (skb_queue_empty(&ra_list->skb_head))
  44                         continue;
  45
  46                 skb_queue_walk_safe(&ra_list->skb_head, skb, tmp) {
  47                         tx_info = MWIFIEX_SKB_TXCB(skb);
  48                         if (tx_info->flags & MWIFIEX_BUF_FLAG_BRIDGED_PKT) {
  49                                 __skb_unlink(skb, &ra_list->skb_head);
  50                                 mwifiex_write_data_complete(adapter, skb, 0,
  51                                                             -1);
  52                                 atomic_dec(&priv->wmm.tx_pkts_queued);
  53                                 pkt_deleted = true;
  54                         }
  55                         if ((atomic_read(&adapter->pending_bridged_pkts) <=
  56                                              MWIFIEX_BRIDGED_PKTS_THR_LOW))
  57                                 break;
  58                 }
  59         }
  60
  61         return pkt_deleted;
  62 }
  63
  64 /* This function deletes packets from particular RA List. RA list index
  65  * from which packets are deleted is preserved so that packets from next RA
  66  * list are deleted upon subsequent call thus maintaining fairness.
  67  */
  68 static void mwifiex_uap_cleanup_tx_queues(struct mwifiex_private *priv)
  69 {
  70         unsigned long flags;
  71         struct list_head *ra_list;
  72         int i;
  73
  74         spin_lock_irqsave(&priv->wmm.ra_list_spinlock, flags);
  75
  76         for (i = 0; i < MAX_NUM_TID; i++, priv->del_list_idx++) {
  77                 if (priv->del_list_idx == MAX_NUM_TID)
  78                         priv->del_list_idx = 0;
  79                 ra_list = &priv->wmm.tid_tbl_ptr[priv->del_list_idx].ra_list;
  80                 if (mwifiex_uap_del_tx_pkts_in_ralist(priv, ra_list)) {
  81                         priv->del_list_idx++;
  82                         break;
  83                 }
  84         }
  85
  86         spin_unlock_irqrestore(&priv->wmm.ra_list_spinlock, flags);
  87 }
  88
  89
  90 static void mwifiex_uap_queue_bridged_pkt(struct mwifiex_private *priv,
  91                                          struct sk_buff *skb)
  92 {
  93         struct mwifiex_adapter *adapter = priv->adapter;
  94         struct uap_rxpd *uap_rx_pd;
  95         struct rx_packet_hdr *rx_pkt_hdr;
  96         struct sk_buff *new_skb;
  97         struct mwifiex_txinfo *tx_info;
  98         int hdr_chop;
  99         struct timeval tv;
 100         struct ethhdr *p_ethhdr;
 101
 102         uap_rx_pd = (struct uap_rxpd *)(skb->data);
 103         rx_pkt_hdr = (void *)uap_rx_pd + le16_to_cpu(uap_rx_pd->rx_pkt_offset);
 104
 105         if ((atomic_read(&adapter->pending_bridged_pkts) >=
 106                                              MWIFIEX_BRIDGED_PKTS_THR_HIGH)) {
 107                 dev_err(priv->adapter->dev,
 108                         "Tx: Bridge packet limit reached. Drop packet!\n");
 109                 kfree_skb(skb);
 110                 mwifiex_uap_cleanup_tx_queues(priv);
 111                 return;
 112         }
 113
 114         if ((!memcmp(&rx_pkt_hdr->rfc1042_hdr, bridge_tunnel_header,
 115                      sizeof(bridge_tunnel_header))) ||
 116             (!memcmp(&rx_pkt_hdr->rfc1042_hdr, rfc1042_header,
 117                      sizeof(rfc1042_header)) &&
 118              ntohs(rx_pkt_hdr->rfc1042_hdr.snap_type) != ETH_P_AARP &&
 119              ntohs(rx_pkt_hdr->rfc1042_hdr.snap_type) != ETH_P_IPX)) {
 120                 /* Replace the 803 header and rfc1042 header (llc/snap) with
 121                  * an Ethernet II header, keep the src/dst and snap_type
 122                  * (ethertype).
 123                  *
 124                  * The firmware only passes up SNAP frames converting all RX
 125                  * data from 802.11 to 802.2/LLC/SNAP frames.
 126                  *
 127                  * To create the Ethernet II, just move the src, dst address
 128                  * right before the snap_type.
 129                  */
 130                 p_ethhdr = (struct ethhdr *)
 131                         ((u8 *)(&rx_pkt_hdr->eth803_hdr)
 132                          + sizeof(rx_pkt_hdr->eth803_hdr)
 133                          + sizeof(rx_pkt_hdr->rfc1042_hdr)
 134                          - sizeof(rx_pkt_hdr->eth803_hdr.h_dest)
 135                          - sizeof(rx_pkt_hdr->eth803_hdr.h_source)
 136                          - sizeof(rx_pkt_hdr->rfc1042_hdr.snap_type));
 137                 memcpy(p_ethhdr->h_source, rx_pkt_hdr->eth803_hdr.h_source,
 138                        sizeof(p_ethhdr->h_source));
 139                 memcpy(p_ethhdr->h_dest, rx_pkt_hdr->eth803_hdr.h_dest,
 140                        sizeof(p_ethhdr->h_dest));
 141                 /* Chop off the rxpd + the excess memory from
 142                  * 802.2/llc/snap header that was removed.
 143                  */
 144                 hdr_chop = (u8 *)p_ethhdr - (u8 *)uap_rx_pd;
 145         } else {
 146                 /* Chop off the rxpd */
 147                 hdr_chop = (u8 *)&rx_pkt_hdr->eth803_hdr - (u8 *)uap_rx_pd;
 148         }
 149
 150         /* Chop off the leading header bytes so that it points
 151          * to the start of either the reconstructed EthII frame
 152          * or the 802.2/llc/snap frame.
 153          */
 154         skb_pull(skb, hdr_chop);
 155
 156         if (skb_headroom(skb) < MWIFIEX_MIN_DATA_HEADER_LEN) {
 157                 dev_dbg(priv->adapter->dev,
 158                         "data: Tx: insufficient skb headroom %d\n",
 159                         skb_headroom(skb));
 160                 /* Insufficient skb headroom - allocate a new skb */
 161                 new_skb =
 162                         skb_realloc_headroom(skb, MWIFIEX_MIN_DATA_HEADER_LEN);
 163                 if (unlikely(!new_skb)) {
 164                         dev_err(priv->adapter->dev,
 165                                 "Tx: cannot allocate new_skb\n");
 166                         kfree_skb(skb);
 167                         priv->stats.tx_dropped++;
 168                         return;
 169                 }
 170
 171                 kfree_skb(skb);
 172                 skb = new_skb;
 173                 dev_dbg(priv->adapter->dev, "info: new skb headroom %d\n",
 174                         skb_headroom(skb));
 175         }
 176
 177         tx_info = MWIFIEX_SKB_TXCB(skb);
 178         memset(tx_info, 0, sizeof(*tx_info));
 179         tx_info->bss_num = priv->bss_num;
 180         tx_info->bss_type = priv->bss_type;
 181         tx_info->flags |= MWIFIEX_BUF_FLAG_BRIDGED_PKT;
 182
 183         if (is_unicast_ether_addr(rx_pkt_hdr->eth803_hdr.h_dest)) {
 184                 /* Update bridge packet statistics as the
 185                  * packet is not going to kernel/upper layer.
 186                  */
 187                 priv->stats.rx_bytes += skb->len;
 188                 priv->stats.rx_packets++;
 189
 190                 /* Sending bridge packet to TX queue, so save the packet
 191                  * length in TXCB to update statistics in TX complete.
 192                  */
 193                 tx_info->pkt_len = skb->len;
 194         }
 195
 196         do_gettimeofday(&tv);
 197         skb->tstamp = timeval_to_ktime(tv);
 198         mwifiex_wmm_add_buf_txqueue(priv, skb);
 199         atomic_inc(&adapter->tx_pending);
 200         atomic_inc(&adapter->pending_bridged_pkts);
 201
 202         return;
 203 }
 204
 205 /*
 206  * This function contains logic for AP packet forwarding.
 207  *
 208  * If a packet is multicast/broadcast, it is sent to kernel/upper layer
 209  * as well as queued back to AP TX queue so that it can be sent to other
 210  * associated stations.
 211  * If a packet is unicast and RA is present in associated station list,
 212  * it is again requeued into AP TX queue.
 213  * If a packet is unicast and RA is not in associated station list,
 214  * packet is forwarded to kernel to handle routing logic.
 215  */
 216 int mwifiex_handle_uap_rx_forward(struct mwifiex_private *priv,
 217                                   struct sk_buff *skb)
 218 {
 219         struct mwifiex_adapter *adapter = priv->adapter;
 220         struct uap_rxpd *uap_rx_pd;
 221         struct rx_packet_hdr *rx_pkt_hdr;
 222         u8 ra[ETH_ALEN];
 223         struct sk_buff *skb_uap;
 224
 225         uap_rx_pd = (struct uap_rxpd *)(skb->data);
 226         rx_pkt_hdr = (void *)uap_rx_pd + le16_to_cpu(uap_rx_pd->rx_pkt_offset);
 227
 228         /* don't do packet forwarding in disconnected state */
 229         if (!priv->media_connected) {
 230                 dev_err(adapter->dev, "drop packet in disconnected state.\n");
 231                 dev_kfree_skb_any(skb);
 232                 return 0;
 233         }
 234
 235         memcpy(ra, rx_pkt_hdr->eth803_hdr.h_dest, ETH_ALEN);
 236
 237         if (is_multicast_ether_addr(ra)) {
 238                 skb_uap = skb_copy(skb, GFP_ATOMIC);
 239                 mwifiex_uap_queue_bridged_pkt(priv, skb_uap);
 240         } else {
 241                 if (mwifiex_get_sta_entry(priv, ra)) {
 242                         /* Requeue Intra-BSS packet */
 243                         mwifiex_uap_queue_bridged_pkt(priv, skb);
 244                         return 0;
 245                 }
 246         }
 247
 248         /* Forward unicat/Inter-BSS packets to kernel. */
 249         return mwifiex_process_rx_packet(priv, skb);
 250 }
 251
 252 /*
 253  * This function processes the packet received on AP interface.
 254  *
 255  * The function looks into the RxPD and performs sanity tests on the
 256  * received buffer to ensure its a valid packet before processing it
 257  * further. If the packet is determined to be aggregated, it is
 258  * de-aggregated accordingly. Then skb is passed to AP packet forwarding logic.
 259  *
 260  * The completion callback is called after processing is complete.
 261  */
 262 int mwifiex_process_uap_rx_packet(struct mwifiex_private *priv,
 263                                   struct sk_buff *skb)
 264 {
 265         struct mwifiex_adapter *adapter = priv->adapter;
 266         int ret;
 267         struct uap_rxpd *uap_rx_pd;
 268         struct rx_packet_hdr *rx_pkt_hdr;
 269         u16 rx_pkt_type;
 270         u8 ta[ETH_ALEN], pkt_type;
 271         struct mwifiex_sta_node *node;
 272
 273         uap_rx_pd = (struct uap_rxpd *)(skb->data);
 274         rx_pkt_type = le16_to_cpu(uap_rx_pd->rx_pkt_type);
 275         rx_pkt_hdr = (void *)uap_rx_pd + le16_to_cpu(uap_rx_pd->rx_pkt_offset);
 276
 277         if ((le16_to_cpu(uap_rx_pd->rx_pkt_offset) +
 278              le16_to_cpu(uap_rx_pd->rx_pkt_length)) > (u16) skb->len) {
 279                 dev_err(adapter->dev,
 280                         "wrong rx packet: len=%d, offset=%d, length=%d\n",
 281                         skb->len, le16_to_cpu(uap_rx_pd->rx_pkt_offset),
 282                         le16_to_cpu(uap_rx_pd->rx_pkt_length));
 283                 priv->stats.rx_dropped++;
 284                 dev_kfree_skb_any(skb);
 285                 return 0;
 286         }
 287
 288         if (rx_pkt_type == PKT_TYPE_MGMT) {
 289                 ret = mwifiex_process_mgmt_packet(priv, skb);
 290                 if (ret)
 291                         dev_err(adapter->dev, "Rx of mgmt packet failed");
 292                 dev_kfree_skb_any(skb);
 293                 return ret;
 294         }
 295
 296         memcpy(ta, rx_pkt_hdr->eth803_hdr.h_source, ETH_ALEN);
 297
 298         if (rx_pkt_type != PKT_TYPE_BAR && uap_rx_pd->priority < MAX_NUM_TID) {
 299                 node = mwifiex_get_sta_entry(priv, ta);
 300                 if (node)
 301                         node->rx_seq[uap_rx_pd->priority] =
 302                                                 le16_to_cpu(uap_rx_pd->seq_num);
 303         }
 304
 305         if (!priv->ap_11n_enabled ||
 306             (!mwifiex_11n_get_rx_reorder_tbl(priv, uap_rx_pd->priority, ta) &&
 307             (le16_to_cpu(uap_rx_pd->rx_pkt_type) != PKT_TYPE_AMSDU))) {
 308                 ret = mwifiex_handle_uap_rx_forward(priv, skb);
 309                 return ret;
 310         }
 311
 312         /* Reorder and send to kernel */
 313         pkt_type = (u8)le16_to_cpu(uap_rx_pd->rx_pkt_type);
 314         ret = mwifiex_11n_rx_reorder_pkt(priv, le16_to_cpu(uap_rx_pd->seq_num),
 315                                          uap_rx_pd->priority, ta, pkt_type,
 316                                          skb);
 317
 318         if (ret || (rx_pkt_type == PKT_TYPE_BAR))
 319                 dev_kfree_skb_any(skb);
 320
 321         if (ret)
 322                 priv->stats.rx_dropped++;
 323
 324         return ret;
 325 }
 326
 327 /*
 328  * This function fills the TxPD for AP tx packets.
 329  *
 330  * The Tx buffer received by this function should already have the
 331  * header space allocated for TxPD.
 332  *
 333  * This function inserts the TxPD in between interface header and actual
 334  * data and adjusts the buffer pointers accordingly.
 335  *
 336  * The following TxPD fields are set by this function, as required -
 337  *      - BSS number
 338  *      - Tx packet length and offset
 339  *      - Priority
 340  *      - Packet delay
 341  *      - Priority specific Tx control
 342  *      - Flags
 343  */
 344 void *mwifiex_process_uap_txpd(struct mwifiex_private *priv,
 345                                struct sk_buff *skb)
 346 {
 347         struct mwifiex_adapter *adapter = priv->adapter;
 348         struct uap_txpd *txpd;
 349         struct mwifiex_txinfo *tx_info = MWIFIEX_SKB_TXCB(skb);
 350         int pad, len;
 351         u16 pkt_type;
 352
 353         if (!skb->len) {
 354                 dev_err(adapter->dev, "Tx: bad packet length: %d\n", skb->len);
 355                 tx_info->status_code = -1;
 356                 return skb->data;
 357         }
 358
 359         pkt_type = mwifiex_is_skb_mgmt_frame(skb) ? PKT_TYPE_MGMT : 0;
 360
 361         /* If skb->data is not aligned, add padding */
 362         pad = (4 - (((void *)skb->data - NULL) & 0x3)) % 4;
 363
 364         len = sizeof(*txpd) + pad;
 365
 366         BUG_ON(skb_headroom(skb) < len + INTF_HEADER_LEN);
 367
 368         skb_push(skb, len);
 369
 370         txpd = (struct uap_txpd *)skb->data;
 371         memset(txpd, 0, sizeof(*txpd));
 372         txpd->bss_num = priv->bss_num;
 373         txpd->bss_type = priv->bss_type;
 374         txpd->tx_pkt_length = cpu_to_le16((u16)(skb->len - len));
 375
 376         txpd->priority = (u8)skb->priority;
 377         txpd->pkt_delay_2ms = mwifiex_wmm_compute_drv_pkt_delay(priv, skb);
 378
 379         if (txpd->priority < ARRAY_SIZE(priv->wmm.user_pri_pkt_tx_ctrl))
 380                 /*
 381                  * Set the priority specific tx_control field, setting of 0 will
 382                  * cause the default value to be used later in this function.
 383                  */
 384                 txpd->tx_control =
 385                     cpu_to_le32(priv->wmm.user_pri_pkt_tx_ctrl[txpd->priority]);
 386
 387         /* Offset of actual data */
 388         if (pkt_type == PKT_TYPE_MGMT) {
 389                 /* Set the packet type and add header for management frame */
 390                 txpd->tx_pkt_type = cpu_to_le16(pkt_type);
 391                 len += MWIFIEX_MGMT_FRAME_HEADER_SIZE;
 392         }
 393
 394         txpd->tx_pkt_offset = cpu_to_le16(len);
 395
 396         /* make space for INTF_HEADER_LEN */
 397         skb_push(skb, INTF_HEADER_LEN);
 398
 399         if (!txpd->tx_control)
 400                 /* TxCtrl set by user or default */
 401                 txpd->tx_control = cpu_to_le32(priv->pkt_tx_ctrl);
 402
 403         return skb->data;
 404 }