[WIRELESS] cfg80211: New wireless config infrastructure.

This patch creates the core cfg80211 code along with some sysfs bits.
This is a stripped down version to allow mac80211 to function, but
doesn't include any configuration yet except for creating and removing
virtual interfaces.

This patch includes the nl80211 header file but it only contains the
interface types which the cfg80211 interface for creating virtual
interfaces relies on.

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>

6 files changed, 353 insertions, 1 deletions

diff --git a/net/wireless/Kconfig b/net/wireless/Kconfig
index ca2f05c..1863c0b 100644
--- a/net/wireless/Kconfig
+++ b/net/wireless/Kconfig
@@ -1,3 +1,6 @@
+config CFG80211
+        tristate "Improved wireless configuration API"
+
 config WIRELESS_EXT
 	bool "Wireless extensions"
 	default n
diff --git a/net/wireless/Makefile b/net/wireless/Makefile
index cf4e3d9..3f082ff 100644
--- a/net/wireless/Makefile
+++ b/net/wireless/Makefile
@@ -1 +1,3 @@
-# dummy file for now
+obj-$(CONFIG_CFG80211) += cfg80211.o
+
+cfg80211-y += core.o sysfs.o
diff --git a/net/wireless/core.c b/net/wireless/core.c
new file mode 100644
index 0000000..532e1e0
--- /dev/null
+++ b/net/wireless/core.c
@@ -0,0 +1,209 @@
+/*
+ * This is the linux wireless configuration interface.
+ *
+ * Copyright 2006, 2007		Johannes Berg <johannes@sipsolutions.net>
+ */
+
+#include <linux/if.h>
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/list.h>
+#include <linux/nl80211.h>
+#include <linux/debugfs.h>
+#include <linux/notifier.h>
+#include <linux/device.h>
+#include <net/genetlink.h>
+#include <net/cfg80211.h>
+#include <net/wireless.h>
+#include "core.h"
+#include "sysfs.h"
+
+/* name for sysfs, %d is appended */
+#define PHY_NAME "phy"
+
+MODULE_AUTHOR("Johannes Berg");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("wireless configuration support");
+
+/* RCU might be appropriate here since we usually
+ * only read the list, and that can happen quite
+ * often because we need to do it for each command */
+LIST_HEAD(cfg80211_drv_list);
+DEFINE_MUTEX(cfg80211_drv_mutex);
+static int wiphy_counter;
+
+/* for debugfs */
+static struct dentry *ieee80211_debugfs_dir;
+
+/* exported functions */
+
+struct wiphy *wiphy_new(struct cfg80211_ops *ops, int sizeof_priv)
+{
+	struct cfg80211_registered_device *drv;
+	int alloc_size;
+
+	alloc_size = sizeof(*drv) + sizeof_priv;
+
+	drv = kzalloc(alloc_size, GFP_KERNEL);
+	if (!drv)
+		return NULL;
+
+	drv->ops = ops;
+
+	mutex_lock(&cfg80211_drv_mutex);
+
+	if (unlikely(wiphy_counter<0)) {
+		/* ugh, wrapped! */
+		kfree(drv);
+		return NULL;
+	}
+	drv->idx = wiphy_counter;
+
+	/* give it a proper name */
+	snprintf(drv->wiphy.dev.bus_id, BUS_ID_SIZE,
+		 PHY_NAME "%d", drv->idx);
+
+	/* now increase counter for the next time */
+	wiphy_counter++;
+	mutex_unlock(&cfg80211_drv_mutex);
+
+	mutex_init(&drv->mtx);
+	mutex_init(&drv->devlist_mtx);
+	INIT_LIST_HEAD(&drv->netdev_list);
+
+	device_initialize(&drv->wiphy.dev);
+	drv->wiphy.dev.class = &ieee80211_class;
+	drv->wiphy.dev.platform_data = drv;
+
+	return &drv->wiphy;
+}
+EXPORT_SYMBOL(wiphy_new);
+
+int wiphy_register(struct wiphy *wiphy)
+{
+	struct cfg80211_registered_device *drv = wiphy_to_dev(wiphy);
+	int res;
+
+	mutex_lock(&cfg80211_drv_mutex);
+
+
+	res = device_add(&drv->wiphy.dev);
+	if (res)
+		goto out_unlock;
+
+	list_add(&drv->list, &cfg80211_drv_list);
+
+	/* add to debugfs */
+	drv->wiphy.debugfsdir =
+		debugfs_create_dir(wiphy_name(&drv->wiphy),
+				   ieee80211_debugfs_dir);
+
+	res = 0;
+out_unlock:
+	mutex_unlock(&cfg80211_drv_mutex);
+	return res;
+}
+EXPORT_SYMBOL(wiphy_register);
+
+void wiphy_unregister(struct wiphy *wiphy)
+{
+	struct cfg80211_registered_device *drv = wiphy_to_dev(wiphy);
+
+	mutex_lock(&cfg80211_drv_mutex);
+
+	/* hold registered driver mutex during list removal as well
+	 * to make sure no commands are in progress at the moment */
+	mutex_lock(&drv->mtx);
+	list_del(&drv->list);
+	mutex_unlock(&drv->mtx);
+
+	device_del(&drv->wiphy.dev);
+	debugfs_remove(drv->wiphy.debugfsdir);
+
+	mutex_unlock(&cfg80211_drv_mutex);
+}
+EXPORT_SYMBOL(wiphy_unregister);
+
+void cfg80211_dev_free(struct cfg80211_registered_device *drv)
+{
+	mutex_destroy(&drv->mtx);
+	mutex_destroy(&drv->devlist_mtx);
+	kfree(drv);
+}
+
+void wiphy_free(struct wiphy *wiphy)
+{
+	put_device(&wiphy->dev);
+}
+EXPORT_SYMBOL(wiphy_free);
+
+static int cfg80211_netdev_notifier_call(struct notifier_block * nb,
+					 unsigned long state,
+					 void *ndev)
+{
+	struct net_device *dev = ndev;
+	struct cfg80211_registered_device *rdev;
+
+	if (!dev->ieee80211_ptr)
+		return 0;
+
+	rdev = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
+
+	switch (state) {
+	case NETDEV_REGISTER:
+		mutex_lock(&rdev->devlist_mtx);
+		list_add(&dev->ieee80211_ptr->list, &rdev->netdev_list);
+		if (sysfs_create_link(&dev->dev.kobj, &rdev->wiphy.dev.kobj,
+				      "phy80211")) {
+			printk(KERN_ERR "wireless: failed to add phy80211 "
+				"symlink to netdev!\n");
+		}
+		dev->ieee80211_ptr->netdev = dev;
+		mutex_unlock(&rdev->devlist_mtx);
+		break;
+	case NETDEV_UNREGISTER:
+		mutex_lock(&rdev->devlist_mtx);
+		if (!list_empty(&dev->ieee80211_ptr->list)) {
+			sysfs_remove_link(&dev->dev.kobj, "phy80211");
+			list_del_init(&dev->ieee80211_ptr->list);
+		}
+		mutex_unlock(&rdev->devlist_mtx);
+		break;
+	}
+
+	return 0;
+}
+
+static struct notifier_block cfg80211_netdev_notifier = {
+	.notifier_call = cfg80211_netdev_notifier_call,
+};
+
+static int cfg80211_init(void)
+{
+	int err = wiphy_sysfs_init();
+	if (err)
+		goto out_fail_sysfs;
+
+	err = register_netdevice_notifier(&cfg80211_netdev_notifier);
+	if (err)
+		goto out_fail_notifier;
+
+	ieee80211_debugfs_dir = debugfs_create_dir("ieee80211", NULL);
+
+	return 0;
+
+out_fail_notifier:
+	wiphy_sysfs_exit();
+out_fail_sysfs:
+	return err;
+}
+module_init(cfg80211_init);
+
+static void cfg80211_exit(void)
+{
+	debugfs_remove(ieee80211_debugfs_dir);
+	unregister_netdevice_notifier(&cfg80211_netdev_notifier);
+	wiphy_sysfs_exit();
+}
+module_exit(cfg80211_exit);
diff --git a/net/wireless/core.h b/net/wireless/core.h
new file mode 100644
index 0000000..158db1e
--- /dev/null
+++ b/net/wireless/core.h
@@ -0,0 +1,49 @@
+/*
+ * Wireless configuration interface internals.
+ *
+ * Copyright 2006, 2007 Johannes Berg <johannes@sipsolutions.net>
+ */
+#ifndef __NET_WIRELESS_CORE_H
+#define __NET_WIRELESS_CORE_H
+#include <linux/mutex.h>
+#include <linux/list.h>
+#include <linux/netdevice.h>
+#include <net/genetlink.h>
+#include <net/wireless.h>
+#include <net/cfg80211.h>
+
+struct cfg80211_registered_device {
+	struct cfg80211_ops *ops;
+	struct list_head list;
+	/* we hold this mutex during any call so that
+	 * we cannot do multiple calls at once, and also
+	 * to avoid the deregister call to proceed while
+	 * any call is in progress */
+	struct mutex mtx;
+
+	/* wiphy index, internal only */
+	int idx;
+
+	/* associate netdev list */
+	struct mutex devlist_mtx;
+	struct list_head netdev_list;
+
+	/* must be last because of the way we do wiphy_priv(),
+	 * and it should at least be aligned to NETDEV_ALIGN */
+	struct wiphy wiphy __attribute__((__aligned__(NETDEV_ALIGN)));
+};
+
+static inline
+struct cfg80211_registered_device *wiphy_to_dev(struct wiphy *wiphy)
+{
+	BUG_ON(!wiphy);
+	return container_of(wiphy, struct cfg80211_registered_device, wiphy);
+}
+
+extern struct mutex cfg80211_drv_mutex;
+extern struct list_head cfg80211_drv_list;
+
+/* free object */
+extern void cfg80211_dev_free(struct cfg80211_registered_device *drv);
+
+#endif /* __NET_WIRELESS_CORE_H */
diff --git a/net/wireless/sysfs.c b/net/wireless/sysfs.c
new file mode 100644
index 0000000..3ebae14
--- /dev/null
+++ b/net/wireless/sysfs.c
@@ -0,0 +1,80 @@
+/*
+ * This file provides /sys/class/ieee80211/<wiphy name>/
+ * and some default attributes.
+ *
+ * Copyright 2005-2006	Jiri Benc <jbenc@suse.cz>
+ * Copyright 2006	Johannes Berg <johannes@sipsolutions.net>
+ *
+ * This file is GPLv2 as found in COPYING.
+ */
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/nl80211.h>
+#include <linux/rtnetlink.h>
+#include <net/cfg80211.h>
+#include "sysfs.h"
+#include "core.h"
+
+static inline struct cfg80211_registered_device *dev_to_rdev(
+	struct device *dev)
+{
+	return container_of(dev, struct cfg80211_registered_device, wiphy.dev);
+}
+
+static ssize_t _show_index(struct device *dev, struct device_attribute *attr,
+			   char *buf)
+{
+	return sprintf(buf, "%d\n", dev_to_rdev(dev)->idx);
+}
+
+static ssize_t _show_permaddr(struct device *dev,
+			      struct device_attribute *attr,
+			      char *buf)
+{
+	char *addr = dev_to_rdev(dev)->wiphy.perm_addr;
+
+	return sprintf(buf, "%.2x:%.2x:%.2x:%.2x:%.2x:%.2x\n",
+		       addr[0], addr[1], addr[2], addr[3], addr[4], addr[5]);
+}
+
+static struct device_attribute ieee80211_dev_attrs[] = {
+	__ATTR(index, S_IRUGO, _show_index, NULL),
+	__ATTR(macaddress, S_IRUGO, _show_permaddr, NULL),
+	{}
+};
+
+static void wiphy_dev_release(struct device *dev)
+{
+	struct cfg80211_registered_device *rdev = dev_to_rdev(dev);
+
+	cfg80211_dev_free(rdev);
+}
+
+static int wiphy_uevent(struct device *dev, char **envp,
+			int num_envp, char *buf, int size)
+{
+	/* TODO, we probably need stuff here */
+	return 0;
+}
+
+struct class ieee80211_class = {
+	.name = "ieee80211",
+	.owner = THIS_MODULE,
+	.dev_release = wiphy_dev_release,
+	.dev_attrs = ieee80211_dev_attrs,
+#ifdef CONFIG_HOTPLUG
+	.dev_uevent = wiphy_uevent,
+#endif
+};
+
+int wiphy_sysfs_init(void)
+{
+	return class_register(&ieee80211_class);
+}
+
+void wiphy_sysfs_exit(void)
+{
+	class_unregister(&ieee80211_class);
+}
diff --git a/net/wireless/sysfs.h b/net/wireless/sysfs.h
new file mode 100644
index 0000000..65acbeb
--- /dev/null
+++ b/net/wireless/sysfs.h
@@ -0,0 +1,9 @@
+#ifndef __WIRELESS_SYSFS_H
+#define __WIRELESS_SYSFS_H
+
+extern int wiphy_sysfs_init(void);
+extern void wiphy_sysfs_exit(void);
+
+extern struct class ieee80211_class;
+
+#endif /* __WIRELESS_SYSFS_H */