Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6

[cascardo/linux.git] / net / mac80211 / ieee80211_rate.c

diff --git a/net/mac80211/ieee80211_rate.c b/net/mac80211/ieee80211_rate.c
index 93abb8f..7254bd6 100644 (file)
--- a/net/mac80211/ieee80211_rate.c
+++ b/net/mac80211/ieee80211_rate.c
@@ -25,13 +25,25 @@ int ieee80211_rate_control_register(struct rate_control_ops *ops)
 {
        struct rate_control_alg *alg;
 
+       if (!ops->name)
+               return -EINVAL;
+
+       mutex_lock(&rate_ctrl_mutex);
+       list_for_each_entry(alg, &rate_ctrl_algs, list) {
+               if (!strcmp(alg->ops->name, ops->name)) {
+                       /* don't register an algorithm twice */
+                       WARN_ON(1);
+                       return -EALREADY;
+               }
+       }
+
        alg = kzalloc(sizeof(*alg), GFP_KERNEL);
        if (alg == NULL) {
+               mutex_unlock(&rate_ctrl_mutex);
                return -ENOMEM;
        }
        alg->ops = ops;
 
-       mutex_lock(&rate_ctrl_mutex);
        list_add_tail(&alg->list, &rate_ctrl_algs);
        mutex_unlock(&rate_ctrl_mutex);
 
@@ -61,9 +73,12 @@ ieee80211_try_rate_control_ops_get(const char *name)
        struct rate_control_alg *alg;
        struct rate_control_ops *ops = NULL;
 
+       if (!name)
+               return NULL;
+
        mutex_lock(&rate_ctrl_mutex);
        list_for_each_entry(alg, &rate_ctrl_algs, list) {
-               if (!name || !strcmp(alg->ops->name, name))
+               if (!strcmp(alg->ops->name, name))
                        if (try_module_get(alg->ops->module)) {
                                ops = alg->ops;
                                break;
@@ -80,9 +95,12 @@ ieee80211_rate_control_ops_get(const char *name)
 {
        struct rate_control_ops *ops;
 
+       if (!name)
+               name = "simple";
+
        ops = ieee80211_try_rate_control_ops_get(name);
        if (!ops) {
-               request_module("rc80211_%s", name ? name : "default");
+               request_module("rc80211_%s", name);
                ops = ieee80211_try_rate_control_ops_get(name);
        }
        return ops;