2013-03-25 15:50:43

by Johannes Berg

[permalink] [raw]
Subject: [PATCH 3.9] mac80211: fix idle handling sequence

From: Johannes Berg <[email protected]>

Corey Richardson reported that my idle handling cleanup
(commit fd0f979a1b, "mac80211: simplify idle handling")
broke ath9k_htc. The reason appears to be that it wants
to go out of idle before switching channels. To fix it,
reimplement that sequence.

Reported-by: Corey Richardson <[email protected]>
Signed-off-by: Johannes Berg <[email protected]>
---
net/mac80211/chan.c | 17 ++++++++++++++---
net/mac80211/ieee80211_i.h | 1 +
net/mac80211/iface.c | 2 +-
3 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c
index 78c0d90..931be41 100644
--- a/net/mac80211/chan.c
+++ b/net/mac80211/chan.c
@@ -63,6 +63,7 @@ ieee80211_new_chanctx(struct ieee80211_local *local,
enum ieee80211_chanctx_mode mode)
{
struct ieee80211_chanctx *ctx;
+ u32 changed;
int err;

lockdep_assert_held(&local->chanctx_mtx);
@@ -76,6 +77,13 @@ ieee80211_new_chanctx(struct ieee80211_local *local,
ctx->conf.rx_chains_dynamic = 1;
ctx->mode = mode;

+ /* acquire mutex to prevent idle from changing */
+ mutex_lock(&local->mtx);
+ /* turn idle off *before* setting channel -- some drivers need that */
+ changed = ieee80211_idle_off(local);
+ if (changed)
+ ieee80211_hw_config(local, changed);
+
if (!local->use_chanctx) {
local->_oper_channel_type =
cfg80211_get_chandef_type(chandef);
@@ -85,14 +93,17 @@ ieee80211_new_chanctx(struct ieee80211_local *local,
err = drv_add_chanctx(local, ctx);
if (err) {
kfree(ctx);
- return ERR_PTR(err);
+ ctx = ERR_PTR(err);
+
+ ieee80211_recalc_idle(local);
+ goto out;
}
}

+ /* and keep the mutex held until the new chanctx is on the list */
list_add_rcu(&ctx->list, &local->chanctx_list);

- mutex_lock(&local->mtx);
- ieee80211_recalc_idle(local);
+ out:
mutex_unlock(&local->mtx);

return ctx;
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 7bdefd9..5672533 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -1362,6 +1362,7 @@ int ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
enum nl80211_iftype type);
void ieee80211_if_remove(struct ieee80211_sub_if_data *sdata);
void ieee80211_remove_interfaces(struct ieee80211_local *local);
+u32 ieee80211_idle_off(struct ieee80211_local *local);
void ieee80211_recalc_idle(struct ieee80211_local *local);
void ieee80211_adjust_monitor_flags(struct ieee80211_sub_if_data *sdata,
const int offset);
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 3bfe261..58150f8 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -78,7 +78,7 @@ void ieee80211_recalc_txpower(struct ieee80211_sub_if_data *sdata)
ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_TXPOWER);
}

-static u32 ieee80211_idle_off(struct ieee80211_local *local)
+u32 ieee80211_idle_off(struct ieee80211_local *local)
{
if (!(local->hw.conf.flags & IEEE80211_CONF_IDLE))
return 0;
--
1.8.0