| Message ID | 20200401062150.3324-5-thomas@adapt-ip.com (mailing list archive) |
|---|---|
| State | RFC |
| Delegated to: | Johannes Berg |
| Headers | show |
| Series | add a KHz component to wireless channels | expand |
On Tue, 2020-03-31 at 23:21 -0700, Thomas Pedersen wrote: > RX status needs a KHz component, so add freq_offset. We > can make ampdu_reference u16 since it is probably > sufficient to be able to distinguish 64k different > A-MPDUs. Is that necessary? Reads like we have 2 bytes free there? And we only need 13 bits for the frequency (up to 8192 MHz, 60 GHz isn't supported), so we could take out a few fractional ones for the S1G part? Dunno, I mean, we probably also don't need the A-MPDU reference, even radiotap doesn't make much representation on this, but it sort of implies that it should be unique in a capture file, for which 16 bits wouldn't be enough? (should probably clarify that though and say that you should look only "close by" or something?) johannes
On 4/1/20 12:08 AM, Johannes Berg wrote: > On Tue, 2020-03-31 at 23:21 -0700, Thomas Pedersen wrote: >> RX status needs a KHz component, so add freq_offset. We >> can make ampdu_reference u16 since it is probably >> sufficient to be able to distinguish 64k different >> A-MPDUs. > > Is that necessary? Reads like we have 2 bytes free there? Indeed there is, maybe this wasn't the case on 4.9 where I originally wrote this patch. > And we only need 13 bits for the frequency (up to 8192 MHz, 60 GHz isn't > supported), so we could take out a few fractional ones for the S1G part? Makes sense, and yeah we really don't need 2 whole bytes to essentially express "+0.5 MHz". Will shorten the frequency and just use a single bit indicating offset or not. > Dunno, I mean, we probably also don't need the A-MPDU reference, even > radiotap doesn't make much representation on this, but it sort of > implies that it should be unique in a capture file, for which 16 bits > wouldn't be enough? (should probably clarify that though and say that > you should look only "close by" or something?) Yeah. I'll drop this for now, but maybe the space will come in handy in the future.
diff --git a/include/net/mac80211.h b/include/net/mac80211.h index b6b4de0e4b5e..459ec57248fc 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -1333,6 +1333,7 @@ enum mac80211_rx_encoding { * @freq: frequency the radio was tuned to when receiving this frame, in MHz * This field must be set for management frames, but isn't strictly needed * for data (other) frames - for those it only affects radiotap reporting. + * @freq_offset: positive KHz component of @freq. * @signal: signal strength when receiving this frame, either in dBm, in dB or * unspecified depending on the hardware capabilities flags * @IEEE80211_HW_SIGNAL_* @@ -1361,9 +1362,10 @@ struct ieee80211_rx_status { u64 mactime; u64 boottime_ns; u32 device_timestamp; - u32 ampdu_reference; u32 flag; + u16 ampdu_reference; u16 freq; + u16 freq_offset; u8 enc_flags; u8 encoding:2, bw:3, he_ru:3; u8 he_gi:2, he_dcm:1; @@ -1379,6 +1381,12 @@ struct ieee80211_rx_status { u8 zero_length_psdu_type; }; +static inline u32 +ieee80211_rx_status_to_khz(struct ieee80211_rx_status *rx_status) +{ + return MHZ_TO_KHZ(rx_status->freq) + rx_status->freq_offset; +} + /** * struct ieee80211_vendor_radiotap - vendor radiotap data information * @present: presence bitmap for this vendor namespace diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index 4eebee49bb7d..e5bcd786e333 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -3669,7 +3669,8 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, sdata_assert_lock(sdata); - channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq); + channel = ieee80211_get_channel_khz(local->hw.wiphy, + ieee80211_rx_status_to_khz(rx_status)); if (!channel) return; @@ -3885,7 +3886,8 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, return; } - if (rx_status->freq != chanctx_conf->def.chan->center_freq) { + if (rx_status->freq != chanctx_conf->def.chan->center_freq || + rx_status->freq_offset != chanctx_conf->def.chan->freq_offset) { rcu_read_unlock(); return; } diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index 91a13aee4378..0b6dca4c0c7d 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -412,6 +412,7 @@ ieee80211_add_rx_radiotap_header(struct ieee80211_local *local, pos++; /* IEEE80211_RADIOTAP_CHANNEL */ + /* TODO: frequency offset in KHz */ put_unaligned_le16(status->freq, pos); pos += 2; if (status->bw == RATE_INFO_BW_10) diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c index 4d14118dddca..5db15996524f 100644 --- a/net/mac80211/scan.c +++ b/net/mac80211/scan.c @@ -275,7 +275,8 @@ void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb) return; } - channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq); + channel = ieee80211_get_channel_khz(local->hw.wiphy, + ieee80211_rx_status_to_khz(rx_status)); if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) return;
RX status needs a KHz component, so add freq_offset. We can make ampdu_reference u16 since it is probably sufficient to be able to distinguish 64k different A-MPDUs. Signed-off-by: Thomas Pedersen <thomas@adapt-ip.com> --- include/net/mac80211.h | 10 +++++++++- net/mac80211/mlme.c | 6 ++++-- net/mac80211/rx.c | 1 + net/mac80211/scan.c | 3 ++- 4 files changed, 16 insertions(+), 4 deletions(-)