On Wed, 2009-03-18 at 14:06 +0200, Kalle Valo wrote: > ieee80211_tx_h_check_assoc() was dropping everything else than probe > requests during software scan. So the nullfunc frame with the power save > bit was dropped and AP never received it. This meant that AP never > buffered any frames for the station during software scan. > > Fix this by allowing to transmit both probe request and nullfunc frames > during software scan. Tested with stlc45xx. > > Signed-off-by: Kalle Valo <kalle.valo@xxxxxxxxx> Thanks for your patience! Acked-by: Johannes Berg <johannes@xxxxxxxxxxxxxxxx> > --- > > net/mac80211/scan.c | 13 +++++++++++++ > net/mac80211/tx.c | 14 +++++++++++++- > 2 files changed, 26 insertions(+), 1 deletions(-) > > diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c > index 5030a3c..46f35dc 100644 > --- a/net/mac80211/scan.c > +++ b/net/mac80211/scan.c > @@ -409,6 +409,19 @@ int ieee80211_start_scan(struct ieee80211_sub_if_data *scan_sdata, > return 0; > } > > + /* > + * Hardware/driver doesn't support hw_scan, so use software > + * scanning instead. First send a nullfunc frame with power save > + * bit on so that AP will buffer the frames for us while we are not > + * listening, then send probe requests to each channel and wait for > + * the responses. After all channels are scanned, tune back to the > + * original channel and send a nullfunc frame with power save bit > + * off to trigger the AP to send us all the buffered frames. > + * > + * Note that while local->sw_scanning is true everything else but > + * nullfunc frames and probe requests will be dropped in > + * ieee80211_tx_h_check_assoc(). > + */ > local->sw_scanning = true; > if (local->ops->sw_scan_start) > local->ops->sw_scan_start(local_to_hw(local)); > diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c > index 457238a..af768fc 100644 > --- a/net/mac80211/tx.c > +++ b/net/mac80211/tx.c > @@ -193,7 +193,19 @@ ieee80211_tx_h_check_assoc(struct ieee80211_tx_data *tx) > return TX_CONTINUE; > > if (unlikely(tx->local->sw_scanning) && > - !ieee80211_is_probe_req(hdr->frame_control)) > + !ieee80211_is_probe_req(hdr->frame_control) && > + !ieee80211_is_nullfunc(hdr->frame_control)) > + /* > + * When software scanning only nullfunc frames (to notify > + * the sleep state to the AP) and probe requests (for the > + * active scan) are allowed, all other frames should not be > + * sent and we should not get here, but if we do > + * nonetheless, drop them to avoid sending them > + * off-channel. See the link below and > + * ieee80211_start_scan() for more. > + * > + * http://article.gmane.org/gmane.linux.kernel.wireless.general/30089 > + */ > return TX_DROP; > > if (tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT) > >
Attachment:
signature.asc
Description: This is a digitally signed message part
