[MAC80211]: improved short preamble handling
Similarly to CTS protection, whether short preambles are used for 802.11b
transmissions should be a per-subif setting, not device global.
For STAs, this patch makes short preamble handling automatic based on the ERP
IE. For APs, hostapd still uses the prism ioctls, but the write ioctl has been
restricted to AP-only subifs.
ieee80211_txrx_data.short_preamble (an unused field) was removed.
Unfortunately, some API changes were required for the following functions:
- ieee80211_generic_frame_duration
- ieee80211_rts_duration
- ieee80211_ctstoself_duration
- ieee80211_rts_get
- ieee80211_ctstoself_get
Affected drivers were updated accordingly.
Signed-off-by: Daniel Drake <dsd@gentoo.org>
Signed-off-by: Jiri Benc <jbenc@suse.cz>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 532cf51..36761c7 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -173,7 +173,7 @@
* to closest integer */
dur = ieee80211_frame_duration(local, 10, rate, erp,
- local->short_preamble);
+ tx->sdata->short_preamble);
if (next_frag_len) {
/* Frame is fragmented: duration increases with time needed to
@@ -182,7 +182,7 @@
/* next fragment */
dur += ieee80211_frame_duration(local, next_frag_len,
txrate->rate, erp,
- local->short_preamble);
+ tx->sdata->short_preamble);
}
return dur;
@@ -627,12 +627,6 @@
tx->u.tx.control->rate = tx->u.tx.rate;
}
tx->u.tx.control->tx_rate = tx->u.tx.rate->val;
- if ((tx->u.tx.rate->flags & IEEE80211_RATE_PREAMBLE2) &&
- tx->local->short_preamble &&
- (!tx->sta || (tx->sta->flags & WLAN_STA_SHORT_PREAMBLE))) {
- tx->u.tx.short_preamble = 1;
- tx->u.tx.control->tx_rate = tx->u.tx.rate->val2;
- }
return TXRX_CONTINUE;
}
@@ -641,6 +635,7 @@
ieee80211_tx_h_misc(struct ieee80211_txrx_data *tx)
{
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;
+ u16 fc = le16_to_cpu(hdr->frame_control);
u16 dur;
struct ieee80211_tx_control *control = tx->u.tx.control;
struct ieee80211_hw_mode *mode = tx->u.tx.mode;
@@ -677,6 +672,16 @@
!(control->flags & IEEE80211_TXCTL_USE_RTS_CTS))
control->flags |= IEEE80211_TXCTL_USE_CTS_PROTECT;
+ /* Transmit data frames using short preambles if the driver supports
+ * short preambles at the selected rate and short preambles are
+ * available on the network at the current point in time. */
+ if (((fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA) &&
+ (tx->u.tx.rate->flags & IEEE80211_RATE_PREAMBLE2) &&
+ tx->sdata->short_preamble &&
+ (!tx->sta || (tx->sta->flags & WLAN_STA_SHORT_PREAMBLE))) {
+ tx->u.tx.control->tx_rate = tx->u.tx.rate->val2;
+ }
+
/* Setup duration field for the first fragment of the frame. Duration
* for remaining fragments will be updated when they are being sent
* to low-level driver in ieee80211_tx(). */
@@ -1750,7 +1755,7 @@
return NULL;
}
- control->tx_rate = (local->short_preamble &&
+ control->tx_rate = (sdata->short_preamble &&
(rate->flags & IEEE80211_RATE_PREAMBLE2)) ?
rate->val2 : rate->val;
control->antenna_sel_tx = local->hw.conf.antenna_sel_tx;
@@ -1765,7 +1770,7 @@
}
EXPORT_SYMBOL(ieee80211_beacon_get);
-void ieee80211_rts_get(struct ieee80211_hw *hw,
+void ieee80211_rts_get(struct ieee80211_hw *hw, int if_id,
const void *frame, size_t frame_len,
const struct ieee80211_tx_control *frame_txctl,
struct ieee80211_rts *rts)
@@ -1775,13 +1780,13 @@
fctl = IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS;
rts->frame_control = cpu_to_le16(fctl);
- rts->duration = ieee80211_rts_duration(hw, frame_len, frame_txctl);
+ rts->duration = ieee80211_rts_duration(hw, if_id, frame_len, frame_txctl);
memcpy(rts->ra, hdr->addr1, sizeof(rts->ra));
memcpy(rts->ta, hdr->addr2, sizeof(rts->ta));
}
EXPORT_SYMBOL(ieee80211_rts_get);
-void ieee80211_ctstoself_get(struct ieee80211_hw *hw,
+void ieee80211_ctstoself_get(struct ieee80211_hw *hw, int if_id,
const void *frame, size_t frame_len,
const struct ieee80211_tx_control *frame_txctl,
struct ieee80211_cts *cts)
@@ -1791,7 +1796,7 @@
fctl = IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS;
cts->frame_control = cpu_to_le16(fctl);
- cts->duration = ieee80211_ctstoself_duration(hw, frame_len, frame_txctl);
+ cts->duration = ieee80211_ctstoself_duration(hw, if_id, frame_len, frame_txctl);
memcpy(cts->ra, hdr->addr1, sizeof(cts->ra));
}
EXPORT_SYMBOL(ieee80211_ctstoself_get);