[PATCH AUTOSEL 5.4 125/130] mac80211: Update rate control on channel change

Sasha Levin
2020-12-23T02:53:39Z

From: Ilan Peer <ilan.peer@intel.com>

[ Upstream commit 44b72ca8163b8cf94384a11fdec716f5478411bf ]

A channel change or a channel bandwidth change can impact the
rate control logic. However, the rate control logic was not updated
before/after such a change, which might result in unexpected
behavior.

Fix this by updating the stations rate control logic when the
corresponding channel context changes.

Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20201206145305.600d967fe3c9.I48305f25cfcc9c032c77c51396e9e9b882748a86@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/mac80211/chan.c | 61 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 61 insertions(+)

diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c
index aae4b36dd78d1..4f0d676e6e2c1 100644
--- a/net/mac80211/chan.c
+++ b/net/mac80211/chan.c
@@ -9,6 +9,7 @@
#include <net/cfg80211.h>
#include "ieee80211_i.h"
#include "driver-ops.h"
+#include "rate.h"

static int ieee80211_chanctx_num_assigned(struct ieee80211_local *local,
struct ieee80211_chanctx *ctx)
@@ -340,10 +341,42 @@ void ieee80211_recalc_chanctx_min_def(struct ieee80211_local *local,
drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_MIN_WIDTH);
}

+static void ieee80211_chan_bw_change(struct ieee80211_local *local,
+ struct ieee80211_chanctx *ctx)
+{
+ struct sta_info *sta;
+ struct ieee80211_supported_band *sband =
+ local->hw.wiphy->bands[ctx->conf.def.chan->band];
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(sta, &local->sta_list,
+ list) {
+ enum ieee80211_sta_rx_bandwidth new_sta_bw;
+
+ if (!ieee80211_sdata_running(sta->sdata))
+ continue;
+
+ if (rcu_access_pointer(sta->sdata->vif.chanctx_conf) !=
+ &ctx->conf)
+ continue;
+
+ new_sta_bw = ieee80211_sta_cur_vht_bw(sta);
+ if (new_sta_bw == sta->sta.bandwidth)
+ continue;
+
+ sta->sta.bandwidth = new_sta_bw;
+ rate_control_rate_update(local, sband, sta,
+ IEEE80211_RC_BW_CHANGED);
+ }
+ rcu_read_unlock();
+}
+
static void ieee80211_change_chanctx(struct ieee80211_local *local,
struct ieee80211_chanctx *ctx,
const struct cfg80211_chan_def *chandef)
{
+ enum nl80211_chan_width width;
+
if (cfg80211_chandef_identical(&ctx->conf.def, chandef)) {
ieee80211_recalc_chanctx_min_def(local, ctx);
return;
@@ -351,7 +384,25 @@ static void ieee80211_change_chanctx(struct ieee80211_local *local,

WARN_ON(!cfg80211_chandef_compatible(&ctx->conf.def, chandef));

+ width = ctx->conf.def.width;
ctx->conf.def = *chandef;
+
+ /* expected to handle only 20/40/80/160 channel widths */
+ switch (chandef->width) {
+ case NL80211_CHAN_WIDTH_20_NOHT:
+ case NL80211_CHAN_WIDTH_20:
+ case NL80211_CHAN_WIDTH_40:
+ case NL80211_CHAN_WIDTH_80:
+ case NL80211_CHAN_WIDTH_80P80:
+ case NL80211_CHAN_WIDTH_160:
+ break;
+ default:
+ WARN_ON(1);
+ }
+
+ if (chandef->width < width)
+ ieee80211_chan_bw_change(local, ctx);
+
drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_WIDTH);
ieee80211_recalc_chanctx_min_def(local, ctx);

@@ -359,6 +410,9 @@ static void ieee80211_change_chanctx(struct ieee80211_local *local,
local->_oper_chandef = *chandef;
ieee80211_hw_config(local, 0);
}
+
+ if (chandef->width > width)
+ ieee80211_chan_bw_change(local, ctx);
}

static struct ieee80211_chanctx *
@@ -1041,8 +1095,14 @@ ieee80211_vif_use_reserved_reassign(struct ieee80211_sub_if_data *sdata)
if (WARN_ON(!chandef))
return -EINVAL;

+ if (old_ctx->conf.def.width > new_ctx->conf.def.width)
+ ieee80211_chan_bw_change(local, new_ctx);
+
ieee80211_change_chanctx(local, new_ctx, chandef);

+ if (old_ctx->conf.def.width < new_ctx->conf.def.width)
+ ieee80211_chan_bw_change(local, new_ctx);
+
vif_chsw[0].vif = &sdata->vif;
vif_chsw[0].old_ctx = &old_ctx->conf;
vif_chsw[0].new_ctx = &new_ctx->conf;
@@ -1433,6 +1493,7 @@ static int ieee80211_vif_use_reserved_switch(struct ieee80211_local *local)
ieee80211_recalc_smps_chanctx(local, ctx);
ieee80211_recalc_radar_chanctx(local, ctx);
ieee80211_recalc_chanctx_min_def(local, ctx);
+ ieee80211_chan_bw_change(local, ctx);

list_for_each_entry_safe(sdata, sdata_tmp, &ctx->reserved_vifs,
reserved_chanctx_list) {
--
2.27.0