From 99ee7cae3bf3ce04e90d7b193d9f4f59a7044d91 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Mon, 29 Aug 2016 23:25:17 +0300 Subject: [PATCH] mac80211: add support for radiotap timestamp field Use the existing device timestamp from the RX status information to add support for the new radiotap timestamp field. Currently only 32-bit counters are supported, but we also add the radiotap mactime where applicable. This new field allows more flexibility in where the timestamp is taken etc. The non-timestamp data in the field is taken from a new field in the hw struct. Signed-off-by: Johannes Berg --- include/net/ieee80211_radiotap.h | 21 +++++++++++++++++++++ include/net/mac80211.h | 12 ++++++++++++ net/mac80211/main.c | 3 +++ net/mac80211/rx.c | 30 ++++++++++++++++++++++++++++++ 4 files changed, 66 insertions(+) diff --git a/include/net/ieee80211_radiotap.h b/include/net/ieee80211_radiotap.h index b0fd9476c538..ba07b9d8ed63 100644 --- a/include/net/ieee80211_radiotap.h +++ b/include/net/ieee80211_radiotap.h @@ -190,6 +190,10 @@ struct ieee80211_radiotap_header { * IEEE80211_RADIOTAP_VHT u16, u8, u8, u8[4], u8, u8, u16 * * Contains VHT information about this frame. + * + * IEEE80211_RADIOTAP_TIMESTAMP u64, u16, u8, u8 variable + * + * Contains timestamp information for this frame. */ enum ieee80211_radiotap_type { IEEE80211_RADIOTAP_TSFT = 0, @@ -214,6 +218,7 @@ enum ieee80211_radiotap_type { IEEE80211_RADIOTAP_MCS = 19, IEEE80211_RADIOTAP_AMPDU_STATUS = 20, IEEE80211_RADIOTAP_VHT = 21, + IEEE80211_RADIOTAP_TIMESTAMP = 22, /* valid in every it_present bitmap, even vendor namespaces */ IEEE80211_RADIOTAP_RADIOTAP_NAMESPACE = 29, @@ -321,6 +326,22 @@ enum ieee80211_radiotap_type { #define IEEE80211_RADIOTAP_CODING_LDPC_USER2 0x04 #define IEEE80211_RADIOTAP_CODING_LDPC_USER3 0x08 +/* For IEEE80211_RADIOTAP_TIMESTAMP */ +#define IEEE80211_RADIOTAP_TIMESTAMP_UNIT_MASK 0x000F +#define IEEE80211_RADIOTAP_TIMESTAMP_UNIT_MS 0x0000 +#define IEEE80211_RADIOTAP_TIMESTAMP_UNIT_US 0x0001 +#define IEEE80211_RADIOTAP_TIMESTAMP_UNIT_NS 0x0003 +#define IEEE80211_RADIOTAP_TIMESTAMP_SPOS_MASK 0x00F0 +#define IEEE80211_RADIOTAP_TIMESTAMP_SPOS_BEGIN_MDPU 0x0000 +#define IEEE80211_RADIOTAP_TIMESTAMP_SPOS_EO_MPDU 0x0010 +#define IEEE80211_RADIOTAP_TIMESTAMP_SPOS_EO_PPDU 0x0020 +#define IEEE80211_RADIOTAP_TIMESTAMP_SPOS_PLCP_SIG_ACQ 0x0030 +#define IEEE80211_RADIOTAP_TIMESTAMP_SPOS_UNKNOWN 0x00F0 + +#define IEEE80211_RADIOTAP_TIMESTAMP_FLAG_64BIT 0x00 +#define IEEE80211_RADIOTAP_TIMESTAMP_FLAG_32BIT 0x01 +#define IEEE80211_RADIOTAP_TIMESTAMP_FLAG_ACCURACY 0x02 + /* helpers */ static inline int ieee80211_get_radiotap_len(unsigned char *data) { diff --git a/include/net/mac80211.h b/include/net/mac80211.h index a1457ca2a30c..08bac23c8de1 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -2145,6 +2145,14 @@ enum ieee80211_hw_flags { * the default is _GI | _BANDWIDTH. * Use the %IEEE80211_RADIOTAP_VHT_KNOWN_* values. * + * @radiotap_timestamp: Information for the radiotap timestamp field; if the + * 'units_pos' member is set to a non-negative value it must be set to + * a combination of a IEEE80211_RADIOTAP_TIMESTAMP_UNIT_* and a + * IEEE80211_RADIOTAP_TIMESTAMP_SPOS_* value, and then the timestamp + * field will be added and populated from the &struct ieee80211_rx_status + * device_timestamp. If the 'accuracy' member is non-negative, it's put + * into the accuracy radiotap field and the accuracy known flag is set. + * * @netdev_features: netdev features to be set in each netdev created * from this HW. Note that not all features are usable with mac80211, * other features will be rejected during HW registration. @@ -2188,6 +2196,10 @@ struct ieee80211_hw { u8 offchannel_tx_hw_queue; u8 radiotap_mcs_details; u16 radiotap_vht_details; + struct { + int units_pos; + s16 accuracy; + } radiotap_timestamp; netdev_features_t netdev_features; u8 uapsd_queues; u8 uapsd_max_sp_len; diff --git a/net/mac80211/main.c b/net/mac80211/main.c index d00ea9b13f49..ac053a9df36d 100644 --- a/net/mac80211/main.c +++ b/net/mac80211/main.c @@ -660,6 +660,9 @@ struct ieee80211_hw *ieee80211_alloc_hw_nm(size_t priv_data_len, ieee80211_roc_setup(local); + local->hw.radiotap_timestamp.units_pos = -1; + local->hw.radiotap_timestamp.accuracy = -1; + return &local->hw; err_free: wiphy_free(wiphy); diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index 6a265aa73a46..284f0f25e22e 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -180,6 +180,11 @@ ieee80211_rx_radiotap_hdrlen(struct ieee80211_local *local, len += 12; } + if (local->hw.radiotap_timestamp.units_pos >= 0) { + len = ALIGN(len, 8); + len += 12; + } + if (status->chains) { /* antenna and antenna signal fields */ len += 2 * hweight8(status->chains); @@ -447,6 +452,31 @@ ieee80211_add_rx_radiotap_header(struct ieee80211_local *local, pos += 2; } + if (local->hw.radiotap_timestamp.units_pos >= 0) { + u16 accuracy = 0; + u8 flags = IEEE80211_RADIOTAP_TIMESTAMP_FLAG_32BIT; + + rthdr->it_present |= + cpu_to_le32(1 << IEEE80211_RADIOTAP_TIMESTAMP); + + /* ensure 8 byte alignment */ + while ((pos - (u8 *)rthdr) & 7) + pos++; + + put_unaligned_le64(status->device_timestamp, pos); + pos += sizeof(u64); + + if (local->hw.radiotap_timestamp.accuracy >= 0) { + accuracy = local->hw.radiotap_timestamp.accuracy; + flags |= IEEE80211_RADIOTAP_TIMESTAMP_FLAG_ACCURACY; + } + put_unaligned_le16(accuracy, pos); + pos += sizeof(u16); + + *pos++ = local->hw.radiotap_timestamp.units_pos; + *pos++ = flags; + } + for_each_set_bit(chain, &chains, IEEE80211_MAX_CHAINS) { *pos++ = status->chain_signal[chain]; *pos++ = chain; -- 2.30.2