mac80211: select and adjust bitrates according to channel mode
The various components accessing the bitrates table must use consider
the used channel bandwidth to select only available rates or calculate
the bitrate correctly.
There are some rates in reduced bandwidth modes which can't be
represented as multiples of 500kbps, like 2.25 MBit/s in 5 MHz mode. The
standard suggests to round up to the next multiple of 500kbps, just do
that in mac80211 as well.
Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
[make rate unsigned in ieee80211_add_tx_radiotap_header(), squash fix]
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index 7f290a8..272a3b3 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -43,16 +43,17 @@
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct ieee80211_local *local = sdata->local;
- int rates, i;
+ int rates_n = 0, i, ri;
struct ieee80211_mgmt *mgmt;
u8 *pos;
struct ieee80211_supported_band *sband;
struct cfg80211_bss *bss;
- u32 bss_change;
+ u32 bss_change, rate_flags, rates = 0, rates_added = 0;
u8 supp_rates[IEEE80211_MAX_SUPP_RATES];
struct cfg80211_chan_def chandef;
struct beacon_data *presp;
int frame_len;
+ int shift;
sdata_assert_lock(sdata);
@@ -99,6 +100,7 @@
memcpy(ifibss->bssid, bssid, ETH_ALEN);
sband = local->hw.wiphy->bands[chan->band];
+ shift = ieee80211_vif_get_shift(&sdata->vif);
/* Build IBSS probe response */
frame_len = sizeof(struct ieee80211_hdr_3addr) +
@@ -134,15 +136,29 @@
memcpy(pos, ifibss->ssid, ifibss->ssid_len);
pos += ifibss->ssid_len;
- rates = min_t(int, 8, sband->n_bitrates);
+ rate_flags = ieee80211_chandef_rate_flags(&chandef);
+ for (i = 0; i < sband->n_bitrates; i++) {
+ if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
+ continue;
+
+ rates |= BIT(i);
+ rates_n++;
+ }
+
*pos++ = WLAN_EID_SUPP_RATES;
- *pos++ = rates;
- for (i = 0; i < rates; i++) {
- int rate = sband->bitrates[i].bitrate;
+ *pos++ = min_t(int, 8, rates_n);
+ for (ri = 0; ri < sband->n_bitrates; ri++) {
+ int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
+ 5 * (1 << shift));
u8 basic = 0;
- if (basic_rates & BIT(i))
+ if (!(rates & BIT(ri)))
+ continue;
+
+ if (basic_rates & BIT(ri))
basic = 0x80;
- *pos++ = basic | (u8) (rate / 5);
+ *pos++ = basic | (u8) rate;
+ if (++rates_added == 8)
+ break;
}
if (sband->band == IEEE80211_BAND_2GHZ) {
@@ -157,15 +173,20 @@
*pos++ = 0;
*pos++ = 0;
- if (sband->n_bitrates > 8) {
+ /* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
+ if (rates_n > 8) {
*pos++ = WLAN_EID_EXT_SUPP_RATES;
- *pos++ = sband->n_bitrates - 8;
- for (i = 8; i < sband->n_bitrates; i++) {
- int rate = sband->bitrates[i].bitrate;
+ *pos++ = rates_n - 8;
+ for (; ri < sband->n_bitrates; ri++) {
+ int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
+ 5 * (1 << shift));
u8 basic = 0;
- if (basic_rates & BIT(i))
+ if (!(rates & BIT(ri)))
+ continue;
+
+ if (basic_rates & BIT(ri))
basic = 0x80;
- *pos++ = basic | (u8) (rate / 5);
+ *pos++ = basic | (u8) rate;
}
}
@@ -244,7 +265,7 @@
sdata->vif.bss_conf.ibss_creator = creator;
ieee80211_bss_info_change_notify(sdata, bss_change);
- ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates);
+ ieee80211_sta_def_wmm_params(sdata, rates, supp_rates);
ifibss->state = IEEE80211_IBSS_MLME_JOINED;
mod_timer(&ifibss->timer,
@@ -268,6 +289,8 @@
u16 beacon_int = cbss->beacon_interval;
const struct cfg80211_bss_ies *ies;
u64 tsf;
+ u32 rate_flags;
+ int shift;
sdata_assert_lock(sdata);
@@ -275,15 +298,24 @@
beacon_int = 10;
sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
+ rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
+ shift = ieee80211_vif_get_shift(&sdata->vif);
basic_rates = 0;
for (i = 0; i < bss->supp_rates_len; i++) {
- int rate = (bss->supp_rates[i] & 0x7f) * 5;
+ int rate = bss->supp_rates[i] & 0x7f;
bool is_basic = !!(bss->supp_rates[i] & 0x80);
for (j = 0; j < sband->n_bitrates; j++) {
- if (sband->bitrates[j].bitrate == rate) {
+ int brate;
+ if ((rate_flags & sband->bitrates[j].flags)
+ != rate_flags)
+ continue;
+
+ brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
+ 5 * (1 << shift));
+ if (brate == rate) {
if (is_basic)
basic_rates |= BIT(j);
break;
@@ -465,7 +497,7 @@
sta = sta_info_get(sdata, mgmt->sa);
if (elems->supp_rates) {
- supp_rates = ieee80211_sta_get_rates(local, elems,
+ supp_rates = ieee80211_sta_get_rates(sdata, elems,
band, NULL);
if (sta) {
u32 prev_rates;
@@ -589,7 +621,7 @@
"beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
mgmt->bssid);
ieee80211_sta_join_ibss(sdata, bss);
- supp_rates = ieee80211_sta_get_rates(local, elems, band, NULL);
+ supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL);
ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
supp_rates);
rcu_read_unlock();
@@ -1024,6 +1056,9 @@
struct cfg80211_ibss_params *params)
{
u32 changed = 0;
+ u32 rate_flags;
+ struct ieee80211_supported_band *sband;
+ int i;
if (params->bssid) {
memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
@@ -1034,6 +1069,14 @@
sdata->u.ibss.privacy = params->privacy;
sdata->u.ibss.control_port = params->control_port;
sdata->u.ibss.basic_rates = params->basic_rates;
+
+ /* fix basic_rates if channel does not support these rates */
+ rate_flags = ieee80211_chandef_rate_flags(¶ms->chandef);
+ sband = sdata->local->hw.wiphy->bands[params->chandef.chan->band];
+ for (i = 0; i < sband->n_bitrates; i++) {
+ if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
+ sdata->u.ibss.basic_rates &= ~BIT(i);
+ }
memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
sizeof(params->mcast_rate));