From a144f378a489b5900c028425cb0d0a7a3fc8c1c1 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 3 Jul 2013 13:34:02 +0200 Subject: [PATCH] mac80211: add per-chain signal information to radiotap When per-chain signal information is available, don't add the antenna field once but instead add a radiotap namespace for each chain containing the chain/antenna number and the signal strength on that chain. Signed-off-by: Johannes Berg Signed-off-by: Johannes Berg --- net/mac80211/rx.c | 69 +++++++++++++++++++++++++++++++++++------------ 1 file changed, 52 insertions(+), 17 deletions(-) diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index 23dbcfc69b3b..c9f2ca43856a 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -87,11 +87,13 @@ ieee80211_rx_radiotap_space(struct ieee80211_local *local, int len; /* always present fields */ - len = sizeof(struct ieee80211_radiotap_header) + 9; + len = sizeof(struct ieee80211_radiotap_header) + 8; - /* allocate extra bitmap */ + /* allocate extra bitmaps */ if (status->vendor_radiotap_len) len += 4; + if (status->chains) + len += 4 * hweight8(status->chains); if (ieee80211_have_rx_timestamp(status)) { len = ALIGN(len, 8); @@ -100,6 +102,10 @@ ieee80211_rx_radiotap_space(struct ieee80211_local *local, if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) len += 1; + /* antenna field, if we don't have per-chain info */ + if (!status->chains) + len += 1; + /* padding for RX_FLAGS if necessary */ len = ALIGN(len, 2); @@ -116,6 +122,11 @@ ieee80211_rx_radiotap_space(struct ieee80211_local *local, len += 12; } + if (status->chains) { + /* antenna and antenna signal fields */ + len += 2 * hweight8(status->chains); + } + if (status->vendor_radiotap_len) { if (WARN_ON_ONCE(status->vendor_radiotap_align == 0)) status->vendor_radiotap_align = 1; @@ -145,8 +156,11 @@ ieee80211_add_rx_radiotap_header(struct ieee80211_local *local, struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); struct ieee80211_radiotap_header *rthdr; unsigned char *pos; + __le32 *it_present; + u32 it_present_val; u16 rx_flags = 0; - int mpdulen; + int mpdulen, chain; + unsigned long chains = status->chains; mpdulen = skb->len; if (!(has_fcs && (local->hw.flags & IEEE80211_HW_RX_INCLUDES_FCS))) @@ -154,25 +168,39 @@ ieee80211_add_rx_radiotap_header(struct ieee80211_local *local, rthdr = (struct ieee80211_radiotap_header *)skb_push(skb, rtap_len); memset(rthdr, 0, rtap_len); + it_present = &rthdr->it_present; /* radiotap header, set always present flags */ - rthdr->it_present = - cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) | - (1 << IEEE80211_RADIOTAP_CHANNEL) | - (1 << IEEE80211_RADIOTAP_ANTENNA) | - (1 << IEEE80211_RADIOTAP_RX_FLAGS)); rthdr->it_len = cpu_to_le16(rtap_len + status->vendor_radiotap_len); + it_present_val = BIT(IEEE80211_RADIOTAP_FLAGS) | + BIT(IEEE80211_RADIOTAP_CHANNEL) | + BIT(IEEE80211_RADIOTAP_RX_FLAGS); + + if (!status->chains) + it_present_val |= BIT(IEEE80211_RADIOTAP_ANTENNA); - pos = (unsigned char *)(rthdr + 1); + for_each_set_bit(chain, &chains, IEEE80211_MAX_CHAINS) { + it_present_val |= + BIT(IEEE80211_RADIOTAP_EXT) | + BIT(IEEE80211_RADIOTAP_RADIOTAP_NAMESPACE); + put_unaligned_le32(it_present_val, it_present); + it_present++; + it_present_val = BIT(IEEE80211_RADIOTAP_ANTENNA) | + BIT(IEEE80211_RADIOTAP_DBM_ANTSIGNAL); + } if (status->vendor_radiotap_len) { - rthdr->it_present |= - cpu_to_le32(BIT(IEEE80211_RADIOTAP_VENDOR_NAMESPACE)) | - cpu_to_le32(BIT(IEEE80211_RADIOTAP_EXT)); - put_unaligned_le32(status->vendor_radiotap_bitmap, pos); - pos += 4; + it_present_val |= BIT(IEEE80211_RADIOTAP_VENDOR_NAMESPACE) | + BIT(IEEE80211_RADIOTAP_EXT); + put_unaligned_le32(it_present_val, it_present); + it_present++; + it_present_val = status->vendor_radiotap_bitmap; } + put_unaligned_le32(it_present_val, it_present); + + pos = (void *)(it_present + 1); + /* the order of the following fields is important */ /* IEEE80211_RADIOTAP_TSFT */ @@ -242,9 +270,11 @@ ieee80211_add_rx_radiotap_header(struct ieee80211_local *local, /* IEEE80211_RADIOTAP_LOCK_QUALITY is missing */ - /* IEEE80211_RADIOTAP_ANTENNA */ - *pos = status->antenna; - pos++; + if (!status->chains) { + /* IEEE80211_RADIOTAP_ANTENNA */ + *pos = status->antenna; + pos++; + } /* IEEE80211_RADIOTAP_DB_ANTNOISE is not used */ @@ -341,6 +371,11 @@ ieee80211_add_rx_radiotap_header(struct ieee80211_local *local, pos += 2; } + for_each_set_bit(chain, &chains, IEEE80211_MAX_CHAINS) { + *pos++ = status->chain_signal[chain]; + *pos++ = chain; + } + if (status->vendor_radiotap_len) { /* ensure 2 byte alignment for the vendor field as required */ if ((pos - (u8 *)rthdr) & 1) -- 2.20.1