From: Shaul Triebitz <shaul.triebitz@xxxxxxxxx>
For certain sounding frames, it may be useful to report them
to userspace even though they don't have a PSDU in order to
determine the PHY parameters (e.g. VHT rate/stream config.)
Add support for this to mac80211.
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: Shaul Triebitz <shaul.triebitz@xxxxxxxxx>
Signed-off-by: Luca Coelho <luciano.coelho@xxxxxxxxx>
---
include/net/ieee80211_radiotap.h | 6 ++++++
include/net/mac80211.h | 7 +++++++
net/mac80211/rx.c | 12 +++++++++++-
3 files changed, 24 insertions(+), 1 deletion(-)
diff --git a/include/net/ieee80211_radiotap.h b/include/net/ieee80211_radiotap.h
index 80d543902b8b..8014153bdd49 100644
--- a/include/net/ieee80211_radiotap.h
+++ b/include/net/ieee80211_radiotap.h
@@ -75,6 +75,7 @@ enum ieee80211_radiotap_presence {
IEEE80211_RADIOTAP_TIMESTAMP = 22,
IEEE80211_RADIOTAP_HE = 23,
IEEE80211_RADIOTAP_HE_MU = 24,
+ IEEE80211_RADIOTAP_ZERO_LEN_PSDU = 26,
IEEE80211_RADIOTAP_LSIG = 27,
/* valid in every it_present bitmap, even vendor namespaces */
@@ -340,6 +341,11 @@ struct ieee80211_radiotap_lsig {
__le16 data1, data2;
};
+enum ieee80211_radiotap_zero_len_psdu_type {
+ IEEE80211_RADIOTAP_ZERO_LEN_PSDU_SOUNDING = 0,
+ IEEE80211_RADIOTAP_ZERO_LEN_PSDU_VENDOR = 0xff,
+};
+
/**
* ieee80211_get_radiotap_len - get radiotap header length
*/
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 8c26d2d36cbe..50bf598abdfd 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1142,6 +1142,10 @@ ieee80211_tx_info_clear_status(struct ieee80211_tx_info *info)
* @RX_FLAG_RADIOTAP_HE_MU: HE MU radiotap data is present
* (&struct ieee80211_radiotap_he_mu)
* @RX_FLAG_RADIOTAP_LSIG: L-SIG radiotap data is present
+ * @RX_FLAG_NO_PSDU: use the frame only for radiotap reporting, with
+ * the "0-length PSDU" field included there. The value for it is
+ * in &struct ieee80211_rx_status. Note that if this value isn't
+ * known the frame shouldn't be reported.
*/
enum mac80211_rx_flags {
RX_FLAG_MMIC_ERROR = BIT(0),
@@ -1173,6 +1177,7 @@ enum mac80211_rx_flags {
RX_FLAG_RADIOTAP_HE = BIT(26),
RX_FLAG_RADIOTAP_HE_MU = BIT(27),
RX_FLAG_RADIOTAP_LSIG = BIT(28),
+ RX_FLAG_NO_PSDU = BIT(29),
};
/**
@@ -1245,6 +1250,7 @@ enum mac80211_rx_encoding {
* @ampdu_reference: A-MPDU reference number, must be a different value for
* each A-MPDU but the same for each subframe within one A-MPDU
* @ampdu_delimiter_crc: A-MPDU delimiter CRC
+ * @zero_length_psdu_type: radiotap type of the 0-length PSDU
*/
struct ieee80211_rx_status {
u64 mactime;
@@ -1265,6 +1271,7 @@ struct ieee80211_rx_status {
u8 chains;
s8 chain_signal[IEEE80211_MAX_CHAINS];
u8 ampdu_delimiter_crc;
+ u8 zero_length_psdu_type;
};
/**
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 66cc2590e88c..5c8eaac8592f 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -115,7 +115,8 @@ static inline bool should_drop_frame(struct sk_buff *skb, int present_fcs_len,
if (status->flag & (RX_FLAG_FAILED_FCS_CRC |
RX_FLAG_FAILED_PLCP_CRC |
- RX_FLAG_ONLY_MONITOR))
+ RX_FLAG_ONLY_MONITOR |
+ RX_FLAG_NO_PSDU))
return true;
if (unlikely(skb->len < 16 + present_fcs_len + rtap_space))
@@ -189,6 +190,9 @@ ieee80211_rx_radiotap_hdrlen(struct ieee80211_local *local,
BUILD_BUG_ON(sizeof(struct ieee80211_radiotap_he_mu) != 12);
}
+ if (status->flag & RX_FLAG_NO_PSDU)
+ len += 1;
+
if (status->flag & RX_FLAG_RADIOTAP_LSIG) {
len = ALIGN(len, 2);
len += 4;
@@ -642,6 +646,12 @@ ieee80211_add_rx_radiotap_header(struct ieee80211_local *local,
pos += sizeof(he_mu);
}
+ if (status->flag & RX_FLAG_NO_PSDU) {
+ rthdr->it_present |=
+ cpu_to_le32(1 << IEEE80211_RADIOTAP_ZERO_LEN_PSDU);
+ *pos++ = status->zero_length_psdu_type;
+ }
+
if (status->flag & RX_FLAG_RADIOTAP_LSIG) {
/* ensure 2 byte alignment */
while ((pos - (u8 *)rthdr) & 1)
--
2.18.0
