aboutsummaryrefslogtreecommitdiff
path: root/net/mac80211/rc80211_pid_algo.c
diff options
context:
space:
mode:
authorJohannes Berg <johannes@sipsolutions.net>2008-02-25 16:27:46 +0100
committerJohn W. Linville <linville@tuxdriver.com>2008-03-06 15:30:46 -0500
commitd0709a65181beb787ef3f58cfe45536a2bb254c8 (patch)
tree29e5f36583b0e0a3f11b291347e57672eab41dad /net/mac80211/rc80211_pid_algo.c
parent5cf121c3cdb955583bf0c5d28c992b7968a4aa1a (diff)
mac80211: RCU-ify STA info structure access
This makes access to the STA hash table/list use RCU to protect against freeing of items. However, it's not a true RCU, the copy step is missing: whenever somebody changes a STA item it is simply updated. This is an existing race condition that is now somewhat understandable. This patch also fixes the race key freeing vs. STA destruction by making sure that sta_info_destroy() is always called under RTNL and frees the key. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
Diffstat (limited to 'net/mac80211/rc80211_pid_algo.c')
-rw-r--r--net/mac80211/rc80211_pid_algo.c25
1 files changed, 14 insertions, 11 deletions
diff --git a/net/mac80211/rc80211_pid_algo.c b/net/mac80211/rc80211_pid_algo.c
index 217c0f487bb..a1993161de9 100644
--- a/net/mac80211/rc80211_pid_algo.c
+++ b/net/mac80211/rc80211_pid_algo.c
@@ -77,7 +77,7 @@ static void rate_control_pid_adjust_rate(struct ieee80211_local *local,
int cur_sorted, new_sorted, probe, tmp, n_bitrates, band;
int cur = sta->txrate_idx;
- sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
+ sdata = sta->sdata;
sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
band = sband->band;
n_bitrates = sband->n_bitrates;
@@ -149,7 +149,7 @@ static void rate_control_pid_sample(struct rc_pid_info *pinfo,
struct sta_info *sta)
{
#ifdef CONFIG_MAC80211_MESH
- struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
+ struct ieee80211_sub_if_data *sdata = sta->sdata;
#endif
struct rc_pid_sta_info *spinfo = sta->rate_ctrl_priv;
struct rc_pid_rateinfo *rinfo = pinfo->rinfo;
@@ -249,23 +249,25 @@ static void rate_control_pid_tx_status(void *priv, struct net_device *dev,
unsigned long period;
struct ieee80211_supported_band *sband;
+ rcu_read_lock();
+
sta = sta_info_get(local, hdr->addr1);
sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
if (!sta)
- return;
+ goto unlock;
/* Don't update the state if we're not controlling the rate. */
- sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
+ sdata = sta->sdata;
if (sdata->bss && sdata->bss->force_unicast_rateidx > -1) {
sta->txrate_idx = sdata->bss->max_ratectrl_rateidx;
- return;
+ goto unlock;
}
/* Ignore all frames that were sent with a different rate than the rate
* we currently advise mac80211 to use. */
if (status->control.tx_rate != &sband->bitrates[sta->txrate_idx])
- goto ignore;
+ goto unlock;
spinfo = sta->rate_ctrl_priv;
spinfo->tx_num_xmit++;
@@ -303,8 +305,8 @@ static void rate_control_pid_tx_status(void *priv, struct net_device *dev,
if (time_after(jiffies, spinfo->last_sample + period))
rate_control_pid_sample(pinfo, local, sta);
-ignore:
- sta_info_put(sta);
+ unlock:
+ rcu_read_unlock();
}
static void rate_control_pid_get_rate(void *priv, struct net_device *dev,
@@ -319,6 +321,8 @@ static void rate_control_pid_get_rate(void *priv, struct net_device *dev,
int rateidx;
u16 fc;
+ rcu_read_lock();
+
sta = sta_info_get(local, hdr->addr1);
/* Send management frames and broadcast/multicast data using lowest
@@ -327,8 +331,7 @@ static void rate_control_pid_get_rate(void *priv, struct net_device *dev,
if ((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA ||
is_multicast_ether_addr(hdr->addr1) || !sta) {
sel->rate = rate_lowest(local, sband, sta);
- if (sta)
- sta_info_put(sta);
+ rcu_read_unlock();
return;
}
@@ -344,7 +347,7 @@ static void rate_control_pid_get_rate(void *priv, struct net_device *dev,
sta->last_txrate_idx = rateidx;
- sta_info_put(sta);
+ rcu_read_unlock();
sel->rate = &sband->bitrates[rateidx];