[NL80211]: add netlink interface to cfg80211

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/wireless/core.c b/net/wireless/core.c
index 9771451..febc33b 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -16,6 +16,7 @@
 #include <net/genetlink.h>
 #include <net/cfg80211.h>
 #include <net/wireless.h>
+#include "nl80211.h"
 #include "core.h"
 #include "sysfs.h"
 
@@ -36,6 +37,146 @@
 /* for debugfs */
 static struct dentry *ieee80211_debugfs_dir;
 
+/* requires cfg80211_drv_mutex to be held! */
+static struct cfg80211_registered_device *cfg80211_drv_by_wiphy(int wiphy)
+{
+	struct cfg80211_registered_device *result = NULL, *drv;
+
+	list_for_each_entry(drv, &cfg80211_drv_list, list) {
+		if (drv->idx == wiphy) {
+			result = drv;
+			break;
+		}
+	}
+
+	return result;
+}
+
+/* requires cfg80211_drv_mutex to be held! */
+static struct cfg80211_registered_device *
+__cfg80211_drv_from_info(struct genl_info *info)
+{
+	int ifindex;
+	struct cfg80211_registered_device *bywiphy = NULL, *byifidx = NULL;
+	struct net_device *dev;
+	int err = -EINVAL;
+
+	if (info->attrs[NL80211_ATTR_WIPHY]) {
+		bywiphy = cfg80211_drv_by_wiphy(
+				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(&init_net, ifindex);
+		if (dev) {
+			if (dev->ieee80211_ptr)
+				byifidx =
+					wiphy_to_dev(dev->ieee80211_ptr->wiphy);
+			dev_put(dev);
+		}
+		err = -ENODEV;
+	}
+
+	if (bywiphy && byifidx) {
+		if (bywiphy != byifidx)
+			return ERR_PTR(-EINVAL);
+		else
+			return bywiphy; /* == byifidx */
+	}
+	if (bywiphy)
+		return bywiphy;
+
+	if (byifidx)
+		return byifidx;
+
+	return ERR_PTR(err);
+}
+
+struct cfg80211_registered_device *
+cfg80211_get_dev_from_info(struct genl_info *info)
+{
+	struct cfg80211_registered_device *drv;
+
+	mutex_lock(&cfg80211_drv_mutex);
+	drv = __cfg80211_drv_from_info(info);
+
+	/* if it is not an error we grab the lock on
+	 * it to assure it won't be going away while
+	 * we operate on it */
+	if (!IS_ERR(drv))
+		mutex_lock(&drv->mtx);
+
+	mutex_unlock(&cfg80211_drv_mutex);
+
+	return drv;
+}
+
+struct cfg80211_registered_device *
+cfg80211_get_dev_from_ifindex(int ifindex)
+{
+	struct cfg80211_registered_device *drv = ERR_PTR(-ENODEV);
+	struct net_device *dev;
+
+	mutex_lock(&cfg80211_drv_mutex);
+	dev = dev_get_by_index(&init_net, ifindex);
+	if (!dev)
+		goto out;
+	if (dev->ieee80211_ptr) {
+		drv = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
+		mutex_lock(&drv->mtx);
+	} else
+		drv = ERR_PTR(-ENODEV);
+	dev_put(dev);
+ out:
+	mutex_unlock(&cfg80211_drv_mutex);
+	return drv;
+}
+
+void cfg80211_put_dev(struct cfg80211_registered_device *drv)
+{
+	BUG_ON(IS_ERR(drv));
+	mutex_unlock(&drv->mtx);
+}
+
+int cfg80211_dev_rename(struct cfg80211_registered_device *rdev,
+			char *newname)
+{
+	int idx, taken = -1, result, digits;
+
+	/* prohibit calling the thing phy%d when %d is not its number */
+	sscanf(newname, PHY_NAME "%d%n", &idx, &taken);
+	if (taken == strlen(newname) && idx != rdev->idx) {
+		/* count number of places needed to print idx */
+		digits = 1;
+		while (idx /= 10)
+			digits++;
+		/*
+		 * deny the name if it is phy<idx> where <idx> is printed
+		 * without leading zeroes. taken == strlen(newname) here
+		 */
+		if (taken == strlen(PHY_NAME) + digits)
+			return -EINVAL;
+	}
+
+	/* this will check for collisions */
+	result = device_rename(&rdev->wiphy.dev, newname);
+	if (result)
+		return result;
+
+	if (!debugfs_rename(rdev->wiphy.debugfsdir->d_parent,
+			    rdev->wiphy.debugfsdir,
+			    rdev->wiphy.debugfsdir->d_parent,
+			    newname))
+		printk(KERN_ERR "cfg80211: failed to rename debugfs dir to %s!\n",
+		       newname);
+
+	nl80211_notify_dev_rename(rdev);
+
+	return 0;
+}
+
 /* exported functions */
 
 struct wiphy *wiphy_new(struct cfg80211_ops *ops, int sizeof_priv)
@@ -204,10 +345,16 @@
 	if (err)
 		goto out_fail_notifier;
 
+	err = nl80211_init();
+	if (err)
+		goto out_fail_nl80211;
+
 	ieee80211_debugfs_dir = debugfs_create_dir("ieee80211", NULL);
 
 	return 0;
 
+out_fail_nl80211:
+	unregister_netdevice_notifier(&cfg80211_netdev_notifier);
 out_fail_notifier:
 	wiphy_sysfs_exit();
 out_fail_sysfs:
@@ -218,6 +365,7 @@
 static void cfg80211_exit(void)
 {
 	debugfs_remove(ieee80211_debugfs_dir);
+	nl80211_exit();
 	unregister_netdevice_notifier(&cfg80211_netdev_notifier);
 	wiphy_sysfs_exit();
 }