nl80211: refactor __cfg80211_rdev_from_info

Refactor the function to make it easier to
extend.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 31 insertions, 28 deletions

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 2d3541c5e058..0ec9779c2b56 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -73,44 +73,47 @@ static int get_rdev_dev_by_ifindex(struct net *netns, struct nlattr **attrs,
 static struct cfg80211_registered_device *
 __cfg80211_rdev_from_info(struct genl_info *info)
 {
-        int ifindex;
-        struct cfg80211_registered_device *bywiphyidx = NULL, *byifidx = NULL;
-        struct net_device *dev;
-        int err = -EINVAL;
+        struct cfg80211_registered_device *rdev = NULL, *tmp;
+        struct net_device *netdev;
 
         assert_cfg80211_lock();
 
-        if (info->attrs[NL80211_ATTR_WIPHY]) {
-                bywiphyidx = cfg80211_rdev_by_wiphy_idx(
+        if (!info->attrs[NL80211_ATTR_WIPHY] &&
+            !info->attrs[NL80211_ATTR_IFINDEX])
+                return ERR_PTR(-EINVAL);
+
+        if (info->attrs[NL80211_ATTR_WIPHY])
+                rdev = cfg80211_rdev_by_wiphy_idx(
                                 nla_get_u32(info->attrs[NL80211_ATTR_WIPHY]));
-                err = -ENODEV;
-        }
 
         if (info->attrs[NL80211_ATTR_IFINDEX]) {
-                ifindex = nla_get_u32(info->attrs[NL80211_ATTR_IFINDEX]);
-                dev = dev_get_by_index(genl_info_net(info), ifindex);
-                if (dev) {
-                        if (dev->ieee80211_ptr)
-                                byifidx =
-                                        wiphy_to_dev(dev->ieee80211_ptr->wiphy);
-                        dev_put(dev);
-                }
-                err = -ENODEV;
-        }
+                int ifindex = nla_get_u32(info->attrs[NL80211_ATTR_IFINDEX]);
+                netdev = dev_get_by_index(genl_info_net(info), ifindex);
+                if (netdev) {
+                        if (netdev->ieee80211_ptr)
+                                tmp = wiphy_to_dev(
+                                                netdev->ieee80211_ptr->wiphy);
+                        else
+                                tmp = NULL;
 
-        if (bywiphyidx && byifidx) {
-                if (bywiphyidx != byifidx)
-                        return ERR_PTR(-EINVAL);
-                else
-                        return bywiphyidx; /* == byifidx */
+                        dev_put(netdev);
+
+                        /* not wireless device -- return error */
+                        if (!tmp)
+                                return ERR_PTR(-EINVAL);
+
+                        /* mismatch -- return error */
+                        if (rdev && tmp != rdev)
+                                return ERR_PTR(-EINVAL);
+
+                        rdev = tmp;
+                }
         }
-        if (bywiphyidx)
-                return bywiphyidx;
 
-        if (byifidx)
-                return byifidx;
+        if (rdev)
+                return rdev;
 
-        return ERR_PTR(err);
+        return ERR_PTR(-ENODEV);
 }
 
 /*