Linux Kernel  3.7.1
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tx.c
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1 /*
2  * This file contains the handling of TX in wlan driver.
3  */
4 #include <linux/hardirq.h>
5 #include <linux/netdevice.h>
6 #include <linux/etherdevice.h>
7 #include <linux/sched.h>
8 #include <linux/export.h>
9 #include <net/cfg80211.h>
10 
11 #include "host.h"
12 #include "radiotap.h"
13 #include "decl.h"
14 #include "defs.h"
15 #include "dev.h"
16 #include "mesh.h"
17 
25 static u32 convert_radiotap_rate_to_mv(u8 rate)
26 {
27  switch (rate) {
28  case 2: /* 1 Mbps */
29  return 0 | (1 << 4);
30  case 4: /* 2 Mbps */
31  return 1 | (1 << 4);
32  case 11: /* 5.5 Mbps */
33  return 2 | (1 << 4);
34  case 22: /* 11 Mbps */
35  return 3 | (1 << 4);
36  case 12: /* 6 Mbps */
37  return 4 | (1 << 4);
38  case 18: /* 9 Mbps */
39  return 5 | (1 << 4);
40  case 24: /* 12 Mbps */
41  return 6 | (1 << 4);
42  case 36: /* 18 Mbps */
43  return 7 | (1 << 4);
44  case 48: /* 24 Mbps */
45  return 8 | (1 << 4);
46  case 72: /* 36 Mbps */
47  return 9 | (1 << 4);
48  case 96: /* 48 Mbps */
49  return 10 | (1 << 4);
50  case 108: /* 54 Mbps */
51  return 11 | (1 << 4);
52  }
53  return 0;
54 }
55 
65 {
66  unsigned long flags;
67  struct lbs_private *priv = dev->ml_priv;
68  struct txpd *txpd;
69  char *p802x_hdr;
72 
74 
75  /* We need to protect against the queues being restarted before
76  we get round to stopping them */
77  spin_lock_irqsave(&priv->driver_lock, flags);
78 
79  if (priv->surpriseremoved)
80  goto free;
81 
82  if (!skb->len || (skb->len > MRVDRV_ETH_TX_PACKET_BUFFER_SIZE)) {
83  lbs_deb_tx("tx err: skb length %d 0 or > %zd\n",
85  /* We'll never manage to send this one; drop it and return 'OK' */
86 
87  dev->stats.tx_dropped++;
88  dev->stats.tx_errors++;
89  goto free;
90  }
91 
92 
93  netif_stop_queue(priv->dev);
94  if (priv->mesh_dev)
95  netif_stop_queue(priv->mesh_dev);
96 
97  if (priv->tx_pending_len) {
98  /* This can happen if packets come in on the mesh and eth
99  device simultaneously -- there's no mutual exclusion on
100  hard_start_xmit() calls between devices. */
101  lbs_deb_tx("Packet on %s while busy\n", dev->name);
102  ret = NETDEV_TX_BUSY;
103  goto unlock;
104  }
105 
106  priv->tx_pending_len = -1;
107  spin_unlock_irqrestore(&priv->driver_lock, flags);
108 
109  lbs_deb_hex(LBS_DEB_TX, "TX Data", skb->data, min_t(unsigned int, skb->len, 100));
110 
111  txpd = (void *)priv->tx_pending_buf;
112  memset(txpd, 0, sizeof(struct txpd));
113 
114  p802x_hdr = skb->data;
115  pkt_len = skb->len;
116 
117  if (priv->wdev->iftype == NL80211_IFTYPE_MONITOR) {
118  struct tx_radiotap_hdr *rtap_hdr = (void *)skb->data;
119 
120  /* set txpd fields from the radiotap header */
121  txpd->tx_control = cpu_to_le32(convert_radiotap_rate_to_mv(rtap_hdr->rate));
122 
123  /* skip the radiotap header */
124  p802x_hdr += sizeof(*rtap_hdr);
125  pkt_len -= sizeof(*rtap_hdr);
126 
127  /* copy destination address from 802.11 header */
128  memcpy(txpd->tx_dest_addr_high, p802x_hdr + 4, ETH_ALEN);
129  } else {
130  /* copy destination address from 802.3 header */
131  memcpy(txpd->tx_dest_addr_high, p802x_hdr, ETH_ALEN);
132  }
133 
134  txpd->tx_packet_length = cpu_to_le16(pkt_len);
135  txpd->tx_packet_location = cpu_to_le32(sizeof(struct txpd));
136 
137  lbs_mesh_set_txpd(priv, dev, txpd);
138 
139  lbs_deb_hex(LBS_DEB_TX, "txpd", (u8 *) &txpd, sizeof(struct txpd));
140 
141  lbs_deb_hex(LBS_DEB_TX, "Tx Data", (u8 *) p802x_hdr, le16_to_cpu(txpd->tx_packet_length));
142 
143  memcpy(&txpd[1], p802x_hdr, le16_to_cpu(txpd->tx_packet_length));
144 
145  spin_lock_irqsave(&priv->driver_lock, flags);
146  priv->tx_pending_len = pkt_len + sizeof(struct txpd);
147 
148  lbs_deb_tx("%s lined up packet\n", __func__);
149 
150  dev->stats.tx_packets++;
151  dev->stats.tx_bytes += skb->len;
152 
153  if (priv->wdev->iftype == NL80211_IFTYPE_MONITOR) {
154  /* Keep the skb to echo it back once Tx feedback is
155  received from FW */
156  skb_orphan(skb);
157 
158  /* Keep the skb around for when we get feedback */
159  priv->currenttxskb = skb;
160  } else {
161  free:
162  dev_kfree_skb_any(skb);
163  }
164 
165  unlock:
166  spin_unlock_irqrestore(&priv->driver_lock, flags);
167  wake_up(&priv->waitq);
168 
169  lbs_deb_leave_args(LBS_DEB_TX, "ret %d", ret);
170  return ret;
171 }
172 
182 void lbs_send_tx_feedback(struct lbs_private *priv, u32 try_count)
183 {
184  struct tx_radiotap_hdr *radiotap_hdr;
185 
186  if (priv->wdev->iftype != NL80211_IFTYPE_MONITOR ||
187  priv->currenttxskb == NULL)
188  return;
189 
190  radiotap_hdr = (struct tx_radiotap_hdr *)priv->currenttxskb->data;
191 
192  radiotap_hdr->data_retries = try_count ?
193  (1 + priv->txretrycount - try_count) : 0;
194 
195  priv->currenttxskb->protocol = eth_type_trans(priv->currenttxskb,
196  priv->dev);
197  netif_rx(priv->currenttxskb);
198 
199  priv->currenttxskb = NULL;
200 
201  if (priv->connect_status == LBS_CONNECTED)
202  netif_wake_queue(priv->dev);
203 
204  if (priv->mesh_dev && netif_running(priv->mesh_dev))
205  netif_wake_queue(priv->mesh_dev);
206 }