iwlwifi: proper monitor support

This patch changes the iwlwifi driver to properly support
monitor interfaces after the filter flags change.

The patch is originally created by Johannes Berg for iwl4965. I fixed some
of the comments and created a similar patch for iwl3945.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 102 insertions, 18 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-3945.c b/drivers/net/wireless/iwlwifi/iwl-3945.c
index 7d15b33b9dcd..a793cd11f738 100644
--- a/drivers/net/wireless/iwlwifi/iwl-3945.c
+++ b/drivers/net/wireless/iwlwifi/iwl-3945.c
@@ -35,9 +35,9 @@
 #include <linux/netdevice.h>
 #include <linux/wireless.h>
 #include <linux/firmware.h>
-#include <net/mac80211.h>
-
 #include <linux/etherdevice.h>
+#include <asm/unaligned.h>
+#include <net/mac80211.h>
 
 #include "iwl-3945.h"
 #include "iwl-helpers.h"
@@ -238,10 +238,102 @@ void iwl3945_hw_rx_statistics(struct iwl3945_priv *priv, struct iwl3945_rx_mem_b
         priv->last_statistics_time = jiffies;
 }
 
+void iwl3945_add_radiotap(struct iwl3945_priv *priv, struct sk_buff *skb,
+                          struct iwl3945_rx_frame_hdr *rx_hdr,
+                          struct ieee80211_rx_status *stats)
+{
+        /* First cache any information we need before we overwrite
+         * the information provided in the skb from the hardware */
+        s8 signal = stats->ssi;
+        s8 noise = 0;
+        int rate = stats->rate;
+        u64 tsf = stats->mactime;
+        __le16 phy_flags_hw = rx_hdr->phy_flags;
+
+        struct iwl3945_rt_rx_hdr {
+                struct ieee80211_radiotap_header rt_hdr;
+                __le64 rt_tsf;          /* TSF */
+                u8 rt_flags;            /* radiotap packet flags */
+                u8 rt_rate;             /* rate in 500kb/s */
+                __le16 rt_channelMHz;   /* channel in MHz */
+                __le16 rt_chbitmask;    /* channel bitfield */
+                s8 rt_dbmsignal;        /* signal in dBm, kluged to signed */
+                s8 rt_dbmnoise;
+                u8 rt_antenna;          /* antenna number */
+        } __attribute__ ((packed)) *iwl3945_rt;
+
+        if (skb_headroom(skb) < sizeof(*iwl3945_rt)) {
+                if (net_ratelimit())
+                        printk(KERN_ERR "not enough headroom [%d] for "
+                               "radiotap head [%d]\n",
+                               skb_headroom(skb), sizeof(*iwl3945_rt));
+                return;
+        }
+
+        /* put radiotap header in front of 802.11 header and data */
+        iwl3945_rt = (void *)skb_push(skb, sizeof(*iwl3945_rt));
+
+        /* initialise radiotap header */
+        iwl3945_rt->rt_hdr.it_version = PKTHDR_RADIOTAP_VERSION;
+        iwl3945_rt->rt_hdr.it_pad = 0;
+
+        /* total header + data */
+        put_unaligned(cpu_to_le16(sizeof(*iwl3945_rt)),
+                      &iwl3945_rt->rt_hdr.it_len);
+
+        /* Indicate all the fields we add to the radiotap header */
+        put_unaligned(cpu_to_le32((1 << IEEE80211_RADIOTAP_TSFT) |
+                                  (1 << IEEE80211_RADIOTAP_FLAGS) |
+                                  (1 << IEEE80211_RADIOTAP_RATE) |
+                                  (1 << IEEE80211_RADIOTAP_CHANNEL) |
+                                  (1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL) |
+                                  (1 << IEEE80211_RADIOTAP_DBM_ANTNOISE) |
+                                  (1 << IEEE80211_RADIOTAP_ANTENNA)),
+                      &iwl3945_rt->rt_hdr.it_present);
+
+        /* Zero the flags, we'll add to them as we go */
+        iwl3945_rt->rt_flags = 0;
+
+        put_unaligned(cpu_to_le64(tsf), &iwl3945_rt->rt_tsf);
+
+        iwl3945_rt->rt_dbmsignal = signal;
+        iwl3945_rt->rt_dbmnoise = noise;
+
+        /* Convert the channel frequency and set the flags */
+        put_unaligned(cpu_to_le16(stats->freq), &iwl3945_rt->rt_channelMHz);
+        if (!(phy_flags_hw & RX_RES_PHY_FLAGS_BAND_24_MSK))
+                put_unaligned(cpu_to_le16(IEEE80211_CHAN_OFDM |
+                                          IEEE80211_CHAN_5GHZ),
+                              &iwl3945_rt->rt_chbitmask);
+        else if (phy_flags_hw & RX_RES_PHY_FLAGS_MOD_CCK_MSK)
+                put_unaligned(cpu_to_le16(IEEE80211_CHAN_CCK |
+                                          IEEE80211_CHAN_2GHZ),
+                              &iwl3945_rt->rt_chbitmask);
+        else    /* 802.11g */
+                put_unaligned(cpu_to_le16(IEEE80211_CHAN_OFDM |
+                                          IEEE80211_CHAN_2GHZ),
+                              &iwl3945_rt->rt_chbitmask);
+
+        rate = iwl3945_rate_index_from_plcp(rate);
+        if (rate == -1)
+                iwl3945_rt->rt_rate = 0;
+        else
+                iwl3945_rt->rt_rate = iwl3945_rates[rate].ieee;
+
+        /* antenna number */
+        iwl3945_rt->rt_antenna =
+                le16_to_cpu(phy_flags_hw & RX_RES_PHY_FLAGS_ANTENNA_MSK) >> 4;
+
+        /* set the preamble flag if we have it */
+        if (phy_flags_hw & RX_RES_PHY_FLAGS_SHORT_PREAMBLE_MSK)
+                iwl3945_rt->rt_flags |= IEEE80211_RADIOTAP_F_SHORTPRE;
+
+        stats->flag |= RX_FLAG_RADIOTAP;
+}
+
 static void iwl3945_handle_data_packet(struct iwl3945_priv *priv, int is_data,
                                    struct iwl3945_rx_mem_buffer *rxb,
-                                   struct ieee80211_rx_status *stats,
-                                   u16 phy_flags)
+                                   struct ieee80211_rx_status *stats)
 {
         struct ieee80211_hdr *hdr;
         struct iwl3945_rx_packet *pkt = (struct iwl3945_rx_packet *)rxb->skb->data;
@@ -261,15 +353,6 @@ static void iwl3945_handle_data_packet(struct iwl3945_priv *priv, int is_data,
                     ("Dropping packet while interface is not open.\n");
                 return;
         }
-        if (priv->iw_mode == IEEE80211_IF_TYPE_MNTR) {
-                if (iwl3945_param_hwcrypto)
-                        iwl3945_set_decrypted_flag(priv, rxb->skb,
-                                               le32_to_cpu(rx_end->status),
-                                               stats);
-                iwl3945_handle_data_packet_monitor(priv, rxb, IWL_RX_DATA(pkt),
-                                               len, stats, phy_flags);
-                return;
-        }
 
         skb_reserve(rxb->skb, (void *)rx_hdr->payload - (void *)pkt);
         /* Set the size of the skb to the size of the frame */
@@ -281,6 +364,9 @@ static void iwl3945_handle_data_packet(struct iwl3945_priv *priv, int is_data,
                 iwl3945_set_decrypted_flag(priv, rxb->skb,
                                        le32_to_cpu(rx_end->status), stats);
 
+        if (priv->add_radiotap)
+                iwl3945_add_radiotap(priv, rxb->skb, rx_hdr, stats);
+
         ieee80211_rx_irqsafe(priv->hw, rxb->skb, stats);
         rxb->skb = NULL;
 }
@@ -295,7 +381,6 @@ static void iwl3945_rx_reply_rx(struct iwl3945_priv *priv,
         struct iwl3945_rx_frame_hdr *rx_hdr = IWL_RX_HDR(pkt);
         struct iwl3945_rx_frame_end *rx_end = IWL_RX_END(pkt);
         struct ieee80211_hdr *header;
-        u16 phy_flags = le16_to_cpu(rx_hdr->phy_flags);
         u16 rx_stats_sig_avg = le16_to_cpu(rx_stats->sig_avg);
         u16 rx_stats_noise_diff = le16_to_cpu(rx_stats->noise_diff);
         struct ieee80211_rx_status stats = {
@@ -325,7 +410,7 @@ static void iwl3945_rx_reply_rx(struct iwl3945_priv *priv,
         }
 
         if (priv->iw_mode == IEEE80211_IF_TYPE_MNTR) {
-                iwl3945_handle_data_packet(priv, 1, rxb, &stats, phy_flags);
+                iwl3945_handle_data_packet(priv, 1, rxb, &stats);
                 return;
         }
 
@@ -479,7 +564,7 @@ static void iwl3945_rx_reply_rx(struct iwl3945_priv *priv,
                         }
                 }
 
-                iwl3945_handle_data_packet(priv, 0, rxb, &stats, phy_flags);
+                iwl3945_handle_data_packet(priv, 0, rxb, &stats);
                 break;
 
         case IEEE80211_FTYPE_CTL:
@@ -496,8 +581,7 @@ static void iwl3945_rx_reply_rx(struct iwl3945_priv *priv,
                                        print_mac(mac2, header->addr2),
                                        print_mac(mac3, header->addr3));
                 else
-                        iwl3945_handle_data_packet(priv, 1, rxb, &stats,
-                                                   phy_flags);
+                        iwl3945_handle_data_packet(priv, 1, rxb, &stats);
                 break;
         }
         }