Return-path: Received: from mail30g.wh2.ocn.ne.jp ([220.111.41.239]:6541 "HELO mail30g.wh2.ocn.ne.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1750866AbYDGE0B (ORCPT ); Mon, 7 Apr 2008 00:26:01 -0400 From: Bruno Randolf Subject: [PATCH 2/2] mac80211: make rx radiotap header more flexible To: ath5k-devel@lists.ath5k.org Cc: mcgrof@gmail.com, jirislaby@gmail.com, mickflemm@gmail.com, linux-wireless@vger.kernel.org, linville@tuxdriver.com, johannes@sipsolutions.net, flamingice@sourmilk.net, jbenc@suse.cz Date: Mon, 07 Apr 2008 13:25:49 +0900 Message-ID: <20080407042549.9026.81997.stgit@localhost> (sfid-20080407_052620_225344_DA47AA4E) In-Reply-To: <20080407042541.9026.59360.stgit@localhost> References: <20080407042541.9026.59360.stgit@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-wireless-owner@vger.kernel.org List-ID: use hw flags and rx flags to determine which fields are present in the header. Signed-off-by: Bruno Randolf --- net/mac80211/rx.c | 187 +++++++++++++++++++++++++++++++++++------------------ 1 files changed, 125 insertions(+), 62 deletions(-) diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index 58dead4..f0cb4e2 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -77,6 +77,126 @@ static inline int should_drop_frame(struct ieee80211_rx_status *status, return 0; } +static int +ieee80211_rx_radiotap_len(struct ieee80211_local *local, + struct ieee80211_rx_status *status) +{ + int len = 9; /* always present fields */ + if (status->flag & RX_FLAG_TSFT) + len += 8; + if (local->hw.flags & IEEE80211_HW_SIGNAL_DB || + local->hw.flags & IEEE80211_HW_SIGNAL_DBM) + len += 1; + if (local->hw.flags & IEEE80211_HW_NOISE_DBM) + len += 1; + + if (len & 1) /* padding for RX_FLAGS if necessary */ + len++; + + return len + sizeof(struct ieee80211_radiotap_header); +} + +/** + * ieee80211_add_rx_radiotap_header - add radiotap header + * + * add a radiotap header containing all the fields which the hardware provided. + */ +static void +ieee80211_add_rx_radiotap_header(struct ieee80211_local *local, + struct sk_buff *skb, + struct ieee80211_rx_status *status, + struct ieee80211_rate *rate, + int rtap_len) +{ + struct ieee80211_radiotap_header *rthdr; + unsigned char *pos; + + rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len); + memset(rthdr, 0, rtap_len); + + /* radiotap header, set always present flags */ + rthdr->it_present = + cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | + (1 << IEEE80211_RADIOTAP_RATE) | + (1 << IEEE80211_RADIOTAP_CHANNEL) | + (1 << IEEE80211_RADIOTAP_ANTENNA) | + (1 << IEEE80211_RADIOTAP_RX_FLAGS)); + rthdr->it_len = cpu_to_le16(rtap_len); + + pos = (unsigned char *)(rthdr+1); + + /* the order of the following fields is important */ + + /* IEEE80211_RADIOTAP_TSFT */ + if (status->flag & RX_FLAG_TSFT) { + *(__le64 *)pos = cpu_to_le64(status->mactime); + rthdr->it_present |= + cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT); + pos += 8; + } + + /* IEEE80211_RADIOTAP_FLAGS */ + if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) + *pos |= IEEE80211_RADIOTAP_F_FCS; + pos++; + + /* IEEE80211_RADIOTAP_RATE */ + *pos = rate->bitrate / 5; + pos++; + + /* IEEE80211_RADIOTAP_CHANNEL */ + *(__le16 *)pos = cpu_to_le16(status->freq); + pos += 2; + if (status->band == IEEE80211_BAND_5GHZ) + *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_OFDM | + IEEE80211_CHAN_5GHZ); + else + *(__le16 *)pos = cpu_to_le16(IEEE80211_CHAN_DYN | + IEEE80211_CHAN_2GHZ); + pos += 2; + + /* IEEE80211_RADIOTAP_DBM_ANTSIGNAL */ + if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) { + *pos = status->signal; + rthdr->it_present |= + cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL); + pos++; + } + + /* IEEE80211_RADIOTAP_DBM_ANTNOISE */ + if (local->hw.flags & IEEE80211_HW_NOISE_DBM) { + *pos = status->noise; + rthdr->it_present |= + cpu_to_le32(1 << IEEE80211_RADIOTAP_DBM_ANTNOISE); + pos++; + } + + /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */ + + /* IEEE80211_RADIOTAP_ANTENNA */ + *pos = status->antenna; + pos++; + + /* IEEE80211_RADIOTAP_DB_ANTSIGNAL */ + if (local->hw.flags & IEEE80211_HW_SIGNAL_DB) { + *pos = status->signal; + rthdr->it_present |= + cpu_to_le32(1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL); + pos++; + } + + /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */ + + /* IEEE80211_RADIOTAP_RX_FLAGS */ + /* ensure 2 byte alignment for the 2 byte field as required */ + if ((pos - (unsigned char *)rthdr) & 1) + pos++; + /* FIXME: when radiotap gets a 'bad PLCP' flag use it here */ + if (status->flag & (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC)) + *(__le16 *)pos |= cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS); + pos += 2; +} + /* * This function copies a received frame to all monitor interfaces and * returns a cleaned-up SKB that no longer includes the FCS nor the @@ -89,17 +209,6 @@ ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb, { struct ieee80211_sub_if_data *sdata; int needed_headroom = 0; - struct ieee80211_radiotap_header *rthdr; - __le64 *rttsft = NULL; - struct ieee80211_rtap_fixed_data { - u8 flags; - u8 rate; - __le16 chan_freq; - __le16 chan_flags; - u8 antsignal; - u8 padding_for_rxflags; - __le16 rx_flags; - } __attribute__ ((packed)) *rtfixed; struct sk_buff *skb, *skb2; struct net_device *prev_dev = NULL; int present_fcs_len = 0; @@ -116,8 +225,8 @@ ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb, if (status->flag & RX_FLAG_RADIOTAP) rtap_len = ieee80211_get_radiotap_len(origskb->data); else - /* room for radiotap header, always present fields and TSFT */ - needed_headroom = sizeof(*rthdr) + sizeof(*rtfixed) + 8; + /* room for the radiotap header based on driver features */ + needed_headroom = ieee80211_rx_radiotap_len(local, status); if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) present_fcs_len = FCS_LEN; @@ -163,55 +272,9 @@ ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb, } /* if necessary, prepend radiotap information */ - if (!(status->flag & RX_FLAG_RADIOTAP)) { - rtfixed = (void *) skb_push(skb, sizeof(*rtfixed)); - rtap_len = sizeof(*rthdr) + sizeof(*rtfixed); - if (status->flag & RX_FLAG_TSFT) { - rttsft = (void *) skb_push(skb, sizeof(*rttsft)); - rtap_len += 8; - } - rthdr = (void *) skb_push(skb, sizeof(*rthdr)); - memset(rthdr, 0, sizeof(*rthdr)); - memset(rtfixed, 0, sizeof(*rtfixed)); - rthdr->it_present = - cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | - (1 << IEEE80211_RADIOTAP_RATE) | - (1 << IEEE80211_RADIOTAP_CHANNEL) | - (1 << IEEE80211_RADIOTAP_DB_ANTSIGNAL) | - (1 << IEEE80211_RADIOTAP_RX_FLAGS)); - rtfixed->flags = 0; - if (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS) - rtfixed->flags |= IEEE80211_RADIOTAP_F_FCS; - - if (rttsft) { - *rttsft = cpu_to_le64(status->mactime); - rthdr->it_present |= - cpu_to_le32(1 << IEEE80211_RADIOTAP_TSFT); - } - - /* FIXME: when radiotap gets a 'bad PLCP' flag use it here */ - rtfixed->rx_flags = 0; - if (status->flag & - (RX_FLAG_FAILED_FCS_CRC | RX_FLAG_FAILED_PLCP_CRC)) - rtfixed->rx_flags |= - cpu_to_le16(IEEE80211_RADIOTAP_F_RX_BADFCS); - - rtfixed->rate = rate->bitrate / 5; - - rtfixed->chan_freq = cpu_to_le16(status->freq); - - if (status->band == IEEE80211_BAND_5GHZ) - rtfixed->chan_flags = - cpu_to_le16(IEEE80211_CHAN_OFDM | - IEEE80211_CHAN_5GHZ); - else - rtfixed->chan_flags = - cpu_to_le16(IEEE80211_CHAN_DYN | - IEEE80211_CHAN_2GHZ); - - rtfixed->antsignal = status->signal; - rthdr->it_len = cpu_to_le16(rtap_len); - } + if (!(status->flag & RX_FLAG_RADIOTAP)) + ieee80211_add_rx_radiotap_header(local, skb, status, rate, + needed_headroom); skb_reset_mac_header(skb); skb->ip_summed = CHECKSUM_UNNECESSARY;