wireless: get rid of pointless request list

We really only need to know the last request at each point in time.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 21 insertions, 69 deletions

diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index 581273d86844..a78902d0d6c9 100644
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c
@@ -44,14 +44,13 @@
 
 /* wiphy is set if this request's initiator is REGDOM_SET_BY_DRIVER */
 struct regulatory_request {
-        struct list_head list;
         struct wiphy *wiphy;
         int granted;
         enum reg_set_by initiator;
         char alpha2[2];
 };
 
-static LIST_HEAD(regulatory_requests);
+static struct regulatory_request *last_request;
 
 /* To trigger userspace events */
 static struct platform_device *reg_pdev;
@@ -201,7 +200,7 @@ static void reset_regdomains(void)
  * core upon initialization */
 static void update_world_regdomain(const struct ieee80211_regdomain *rd)
 {
-        BUG_ON(list_empty(&regulatory_requests));
+        BUG_ON(!last_request);
 
         reset_regdomains();
 
@@ -302,15 +301,10 @@ static int call_crda(const char *alpha2)
 static int ignore_request(struct wiphy *wiphy, enum reg_set_by set_by,
         char *alpha2, struct ieee80211_regdomain *rd)
 {
-        struct regulatory_request *last_request = NULL;
-
         /* All initial requests are respected */
-        if (list_empty(&regulatory_requests))
+        if (!last_request)
                 return 0;
 
-        last_request = list_first_entry(&regulatory_requests,
-                struct regulatory_request, list);
-
         switch (set_by) {
         case REGDOM_SET_BY_INIT:
                 return -EINVAL;
@@ -320,7 +314,7 @@ static int ignore_request(struct wiphy *wiphy, enum reg_set_by set_by,
                  * anyway */
                 return 0;
         case REGDOM_SET_BY_COUNTRY_IE:
-                if (last_request->initiator == set_by) {
+                if (last_request->initiator == REGDOM_SET_BY_COUNTRY_IE) {
                         if (last_request->wiphy != wiphy) {
                                 /* Two cards with two APs claiming different
                                  * different Country IE alpha2s!
@@ -350,7 +344,7 @@ static int ignore_request(struct wiphy *wiphy, enum reg_set_by set_by,
                 return 1;
         case REGDOM_SET_BY_DRIVER:
                 BUG_ON(!wiphy);
-                if (last_request->initiator == set_by) {
+                if (last_request->initiator == REGDOM_SET_BY_DRIVER) {
                         /* Two separate drivers hinting different things,
                          * this is possible if you have two devices present
                          * on a system with different EEPROM regulatory
@@ -376,8 +370,8 @@ static int ignore_request(struct wiphy *wiphy, enum reg_set_by set_by,
                         return 0;
                 return 0;
         case REGDOM_SET_BY_USER:
-                if (last_request->initiator == set_by ||
-                                last_request->initiator == REGDOM_SET_BY_CORE)
+                if (last_request->initiator == REGDOM_SET_BY_USER ||
+                    last_request->initiator == REGDOM_SET_BY_CORE)
                         return 0;
                 /* Drivers can use their wiphy's reg_notifier()
                  * to override any information */
@@ -392,26 +386,13 @@ static int ignore_request(struct wiphy *wiphy, enum reg_set_by set_by,
         }
 }
 
-static bool __reg_is_valid_request(const char *alpha2,
-        struct regulatory_request **request)
-{
-        struct regulatory_request *req;
-        if (list_empty(&regulatory_requests))
-                return false;
-        list_for_each_entry(req, &regulatory_requests, list) {
-                if (alpha2_equal(req->alpha2, alpha2)) {
-                        *request = req;
-                        return true;
-                }
-        }
-        return false;
-}
-
 /* Used by nl80211 before kmalloc'ing our regulatory domain */
 bool reg_is_valid_request(const char *alpha2)
 {
-        struct regulatory_request *request = NULL;
-        return  __reg_is_valid_request(alpha2, &request);
+        if (!last_request)
+                return false;
+
+        return alpha2_equal(last_request->alpha2, alpha2);
 }
 
 /* Sanity check on a regulatory rule */
@@ -607,7 +588,8 @@ int __regulatory_hint(struct wiphy *wiphy, enum reg_set_by set_by,
                 request->initiator = set_by;
                 request->wiphy = wiphy;
 
-                list_add_tail(&request->list, &regulatory_requests);
+                kfree(last_request);
+                last_request = request;
                 if (rd)
                         break;
                 r = call_crda(alpha2);
@@ -711,12 +693,10 @@ void print_regdomain_info(const struct ieee80211_regdomain *rd)
 
 static int __set_regdom(const struct ieee80211_regdomain *rd)
 {
-        struct regulatory_request *request = NULL;
-
         /* Some basic sanity checks first */
 
         if (is_world_regdom(rd->alpha2)) {
-                if (WARN_ON(!__reg_is_valid_request(rd->alpha2, &request)))
+                if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
                         return -EINVAL;
                 update_world_regdomain(rd);
                 return 0;
@@ -726,7 +706,7 @@ static int __set_regdom(const struct ieee80211_regdomain *rd)
                         !is_unknown_alpha2(rd->alpha2))
                 return -EINVAL;
 
-        if (list_empty(&regulatory_requests))
+        if (!last_request)
                 return -EINVAL;
 
         /* allow overriding the static definitions if CRDA is present */
@@ -739,13 +719,13 @@ static int __set_regdom(const struct ieee80211_regdomain *rd)
          * to review or adjust their own settings based on their own
          * internal EEPROM data */
 
-        if (WARN_ON(!__reg_is_valid_request(rd->alpha2, &request)))
+        if (WARN_ON(!reg_is_valid_request(rd->alpha2)))
                 return -EINVAL;
 
         reset_regdomains();
 
         /* Country IE parsing coming soon */
-        switch (request->initiator) {
+        switch (last_request->initiator) {
         case REGDOM_SET_BY_CORE:
         case REGDOM_SET_BY_DRIVER:
         case REGDOM_SET_BY_USER:
@@ -764,7 +744,7 @@ static int __set_regdom(const struct ieee80211_regdomain *rd)
 
         /* Tada! */
         cfg80211_regdomain = rd;
-        request->granted = 1;
+        last_request->granted = 1;
 
         return 0;
 }
@@ -776,42 +756,18 @@ static int __set_regdom(const struct ieee80211_regdomain *rd)
  * the passed rd. Caller must hold cfg80211_drv_mutex */
 int set_regdom(const struct ieee80211_regdomain *rd)
 {
-        struct regulatory_request *this_request = NULL, *prev_request = NULL;
         int r;
 
-        if (!list_empty(&regulatory_requests))
-                prev_request = list_first_entry(&regulatory_requests,
-                        struct regulatory_request, list);
-
         /* Note that this doesn't update the wiphys, this is done below */
         r = __set_regdom(rd);
         if (r)
                 return r;
 
-        BUG_ON((!__reg_is_valid_request(rd->alpha2, &this_request)));
-
-        /* The initial standard core update of the world regulatory domain, no
-         * need to keep that request info around if it didn't fail. */
-        if (is_world_regdom(rd->alpha2) &&
-                        this_request->initiator == REGDOM_SET_BY_CORE &&
-                        this_request->granted) {
-                list_del(&this_request->list);
-                kfree(this_request);
-                this_request = NULL;
-        }
-
-        /* Remove old requests, we only leave behind the last one */
-        if (prev_request) {
-                list_del(&prev_request->list);
-                kfree(prev_request);
-                prev_request = NULL;
-        }
-
         /* This would make this whole thing pointless */
         BUG_ON(rd != cfg80211_regdomain);
 
         /* update all wiphys now with the new established regulatory domain */
-        update_all_wiphy_regulatory(this_request->initiator);
+        update_all_wiphy_regulatory(last_request->initiator);
 
         print_regdomain(rd);
 
@@ -853,16 +809,12 @@ int regulatory_init(void)
 
 void regulatory_exit(void)
 {
-        struct regulatory_request *req, *req_tmp;
-
         mutex_lock(&cfg80211_drv_mutex);
 
         reset_regdomains();
 
-        list_for_each_entry_safe(req, req_tmp, &regulatory_requests, list) {
-                list_del(&req->list);
-                kfree(req);
-        }
+        kfree(last_request);
+
         platform_device_unregister(reg_pdev);
 
         mutex_unlock(&cfg80211_drv_mutex);