From 0288157b2ad085e564fb563fbe7794c9ffae4169 Mon Sep 17 00:00:00 2001 From: Michal Kazior Date: Wed, 9 Apr 2014 15:29:28 +0200 Subject: [PATCH] mac80211: improve find_chanctx() for reservations This allows new vifs to be assigned to a chanctx as long as chanctx's reservation chandefs (if any) and chanctx's current chandef (implied by assigned vifs at the time, if any) and the new vif chandef are all compatible. This implies it is impossible to assign a new vif to an in-place reservation chanctx. This gives no advantages for single-channel hardware. It makes sense for multi-channel hardware only. Signed-off-by: Michal Kazior Signed-off-by: Johannes Berg --- net/mac80211/chan.c | 56 +++++++++++++++++++++++---------------------- 1 file changed, 29 insertions(+), 27 deletions(-) diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c index 79eac96d9e5f..0dfb04a07f30 100644 --- a/net/mac80211/chan.c +++ b/net/mac80211/chan.c @@ -28,6 +28,29 @@ static bool ieee80211_can_create_new_chanctx(struct ieee80211_local *local) return ieee80211_num_chanctx(local) < ieee80211_max_num_channels(local); } +static const struct cfg80211_chan_def * +ieee80211_chanctx_reserved_chandef(struct ieee80211_local *local, + struct ieee80211_chanctx *ctx, + const struct cfg80211_chan_def *compat) +{ + struct ieee80211_sub_if_data *sdata; + + lockdep_assert_held(&local->chanctx_mtx); + + list_for_each_entry(sdata, &ctx->reserved_vifs, + reserved_chanctx_list) { + if (!compat) + compat = &sdata->reserved_chandef; + + compat = cfg80211_chandef_compatible(&sdata->reserved_chandef, + compat); + if (!compat) + break; + } + + return compat; +} + static enum nl80211_chan_width ieee80211_get_sta_bw(struct ieee80211_sta *sta) { switch (sta->bandwidth) { @@ -187,27 +210,6 @@ static void ieee80211_change_chanctx(struct ieee80211_local *local, } } -static bool ieee80211_chanctx_is_reserved(struct ieee80211_local *local, - struct ieee80211_chanctx *ctx) -{ - struct ieee80211_sub_if_data *sdata; - bool ret = false; - - lockdep_assert_held(&local->chanctx_mtx); - rcu_read_lock(); - list_for_each_entry_rcu(sdata, &local->interfaces, list) { - if (!ieee80211_sdata_running(sdata)) - continue; - if (sdata->reserved_chanctx == ctx) { - ret = true; - break; - } - } - - rcu_read_unlock(); - return ret; -} - static struct ieee80211_chanctx * ieee80211_find_chanctx(struct ieee80211_local *local, const struct cfg80211_chan_def *chandef, @@ -223,18 +225,18 @@ ieee80211_find_chanctx(struct ieee80211_local *local, list_for_each_entry(ctx, &local->chanctx_list, list) { const struct cfg80211_chan_def *compat; - /* We don't support chanctx reservation for multiple - * vifs yet, so don't allow reserved chanctxs to be - * reused. - */ - if ((ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE) || - ieee80211_chanctx_is_reserved(local, ctx)) + if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE) continue; compat = cfg80211_chandef_compatible(&ctx->conf.def, chandef); if (!compat) continue; + compat = ieee80211_chanctx_reserved_chandef(local, ctx, + compat); + if (!compat) + continue; + ieee80211_change_chanctx(local, ctx, compat); return ctx; -- 2.20.1