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Commit 89a54e48 authored by Johannes Berg's avatar Johannes Berg
Browse files

nl80211: prepare for non-netdev wireless devs 



In order to support a P2P device abstraction and
Bluetooth high-speed AMPs, we need to have a way
to identify virtual interfaces that don't have a
netdev associated.

Do this by adding a NL80211_ATTR_WDEV attribute
to identify a wdev which may or may not also be
a netdev.

To simplify things, use a 64-bit value with the
high 32 bits being the wiphy index for this new
wdev identifier in the nl80211 API.

Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent f72b85b8

include/linux/nl80211.h

+5 −0
Original line number Diff line number Diff line
@@ -771,6 +771,9 @@ enum nl80211_commands { 
 * @NL80211_ATTR_IFNAME: network interface name

 * @NL80211_ATTR_IFTYPE: type of virtual interface, see &enum nl80211_iftype

 *

 * @NL80211_ATTR_WDEV: wireless device identifier, used for pseudo-devices

 *	that don't have a netdev (u64)

 *

 * @NL80211_ATTR_MAC: MAC address (various uses)

 *

 * @NL80211_ATTR_KEY_DATA: (temporal) key data; for TKIP this consists of
@@ -1493,6 +1496,8 @@ enum nl80211_attrs { 


	NL80211_ATTR_BG_SCAN_PERIOD,



	NL80211_ATTR_WDEV,



	/* add attributes here, update the policy in nl80211.c */



	__NL80211_ATTR_AFTER_LAST,

include/net/cfg80211.h

+16 −6
Original line number Diff line number Diff line
@@ -2341,17 +2341,25 @@ struct cfg80211_internal_bss; 
struct cfg80211_cached_keys;



/**

 * struct wireless_dev - wireless per-netdev state

 * struct wireless_dev - wireless device state

 *

 * This structure must be allocated by the driver/stack

 * that uses the ieee80211_ptr field in struct net_device

 * (this is intentional so it can be allocated along with

 * the netdev.)

 * For netdevs, this structure must be allocated by the driver

 * that uses the ieee80211_ptr field in struct net_device (this

 * is intentional so it can be allocated along with the netdev.)

 * It need not be registered then as netdev registration will

 * be intercepted by cfg80211 to see the new wireless device.

 *

 * For non-netdev uses, it must also be allocated by the driver

 * in response to the cfg80211 callbacks that require it, as

 * there's no netdev registration in that case it may not be

 * allocated outside of callback operations that return it.

 *

 * @wiphy: pointer to hardware description

 * @iftype: interface type

 * @list: (private) Used to collect the interfaces

 * @netdev: (private) Used to reference back to the netdev

 * @netdev: (private) Used to reference back to the netdev, may be %NULL

 * @identifier: (private) Identifier used in nl80211 to identify this

 *	wireless device if it has no netdev

 * @current_bss: (private) Used by the internal configuration code

 * @channel: (private) Used by the internal configuration code to track

 *	the user-set AP, monitor and WDS channel
@@ -2383,6 +2391,8 @@ struct wireless_dev { 
	struct list_head list;

	struct net_device *netdev;



	u32 identifier;



	struct list_head mgmt_registrations;

	spinlock_t mgmt_registrations_lock;

net/wireless/core.c

+7 −6
Original line number Diff line number Diff line
@@ -176,7 +176,7 @@ int cfg80211_switch_netns(struct cfg80211_registered_device *rdev, 
	if (!(rdev->wiphy.flags & WIPHY_FLAG_NETNS_OK))

		return -EOPNOTSUPP;



	list_for_each_entry(wdev, &rdev->netdev_list, list) {

	list_for_each_entry(wdev, &rdev->wdev_list, list) {

		wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;

		err = dev_change_net_namespace(wdev->netdev, net, "wlan%d");

		if (err)
@@ -188,7 +188,7 @@ int cfg80211_switch_netns(struct cfg80211_registered_device *rdev, 
		/* failed -- clean up to old netns */

		net = wiphy_net(&rdev->wiphy);



		list_for_each_entry_continue_reverse(wdev, &rdev->netdev_list,

		list_for_each_entry_continue_reverse(wdev, &rdev->wdev_list,

						     list) {

			wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;

			err = dev_change_net_namespace(wdev->netdev, net,
@@ -226,7 +226,7 @@ static int cfg80211_rfkill_set_block(void *data, bool blocked) 
	rtnl_lock();

	mutex_lock(&rdev->devlist_mtx);



	list_for_each_entry(wdev, &rdev->netdev_list, list)

	list_for_each_entry(wdev, &rdev->wdev_list, list)

		dev_close(wdev->netdev);



	mutex_unlock(&rdev->devlist_mtx);
@@ -304,7 +304,7 @@ struct wiphy *wiphy_new(const struct cfg80211_ops *ops, int sizeof_priv) 
	mutex_init(&rdev->mtx);

	mutex_init(&rdev->devlist_mtx);

	mutex_init(&rdev->sched_scan_mtx);

	INIT_LIST_HEAD(&rdev->netdev_list);

	INIT_LIST_HEAD(&rdev->wdev_list);

	spin_lock_init(&rdev->bss_lock);

	INIT_LIST_HEAD(&rdev->bss_list);

	INIT_WORK(&rdev->scan_done_wk, __cfg80211_scan_done);
@@ -622,7 +622,7 @@ void wiphy_unregister(struct wiphy *wiphy) 
		__count == 0; }));



	mutex_lock(&rdev->devlist_mtx);

	BUG_ON(!list_empty(&rdev->netdev_list));

	BUG_ON(!list_empty(&rdev->wdev_list));

	mutex_unlock(&rdev->devlist_mtx);



	/*
@@ -821,7 +821,8 @@ static int cfg80211_netdev_notifier_call(struct notifier_block *nb, 
		spin_lock_init(&wdev->mgmt_registrations_lock);



		mutex_lock(&rdev->devlist_mtx);

		list_add_rcu(&wdev->list, &rdev->netdev_list);

		wdev->identifier = ++rdev->wdev_id;

		list_add_rcu(&wdev->list, &rdev->wdev_list);

		rdev->devlist_generation++;

		/* can only change netns with wiphy */

		dev->features |= NETIF_F_NETNS_LOCAL;

net/wireless/core.h

+3 −3
Original line number Diff line number Diff line
@@ -47,11 +47,11 @@ struct cfg80211_registered_device { 
	/* wiphy index, internal only */

	int wiphy_idx;



	/* associate netdev list */

	/* associated wireless interfaces */

	struct mutex devlist_mtx;

	/* protected by devlist_mtx or RCU */

	struct list_head netdev_list;

	int devlist_generation;

	struct list_head wdev_list;

	int devlist_generation, wdev_id;

	int opencount; /* also protected by devlist_mtx */

	wait_queue_head_t dev_wait;

net/wireless/nl80211.c

+108 −27
Original line number Diff line number Diff line
@@ -46,28 +46,60 @@ static struct genl_family nl80211_fam = { 
	.post_doit = nl80211_post_doit,

};



/* internal helper: get rdev and dev */

static int get_rdev_dev_by_ifindex(struct net *netns, struct nlattr **attrs,

				   struct cfg80211_registered_device **rdev,

				   struct net_device **dev)

/* returns ERR_PTR values */

static struct wireless_dev *

__cfg80211_wdev_from_attrs(struct net *netns, struct nlattr **attrs)

{

	int ifindex;

	struct cfg80211_registered_device *rdev;

	struct wireless_dev *result = NULL;

	bool have_ifidx = attrs[NL80211_ATTR_IFINDEX];

	bool have_wdev_id = attrs[NL80211_ATTR_WDEV];

	u64 wdev_id;

	int wiphy_idx = -1;

	int ifidx = -1;



	if (!attrs[NL80211_ATTR_IFINDEX])

		return -EINVAL;

	assert_cfg80211_lock();



	ifindex = nla_get_u32(attrs[NL80211_ATTR_IFINDEX]);

	*dev = dev_get_by_index(netns, ifindex);

	if (!*dev)

		return -ENODEV;

	if (!have_ifidx && !have_wdev_id)

		return ERR_PTR(-EINVAL);



	*rdev = cfg80211_get_dev_from_ifindex(netns, ifindex);

	if (IS_ERR(*rdev)) {

		dev_put(*dev);

		return PTR_ERR(*rdev);

	if (have_ifidx)

		ifidx = nla_get_u32(attrs[NL80211_ATTR_IFINDEX]);

	if (have_wdev_id) {

		wdev_id = nla_get_u64(attrs[NL80211_ATTR_WDEV]);

		wiphy_idx = wdev_id >> 32;

	}



	return 0;

	list_for_each_entry(rdev, &cfg80211_rdev_list, list) {

		struct wireless_dev *wdev;



		if (wiphy_net(&rdev->wiphy) != netns)

			continue;



		if (have_wdev_id && rdev->wiphy_idx != wiphy_idx)

			continue;



		mutex_lock(&rdev->devlist_mtx);

		list_for_each_entry(wdev, &rdev->wdev_list, list) {

			if (have_ifidx && wdev->netdev &&

			    wdev->netdev->ifindex == ifidx) {

				result = wdev;

				break;

			}

			if (have_wdev_id && wdev->identifier == (u32)wdev_id) {

				result = wdev;

				break;

			}

		}

		mutex_unlock(&rdev->devlist_mtx);



		if (result)

			break;

	}



	if (result)

		return result;

	return ERR_PTR(-ENODEV);

}



static struct cfg80211_registered_device *
@@ -79,13 +111,40 @@ __cfg80211_rdev_from_attrs(struct net *netns, struct nlattr **attrs) 
	assert_cfg80211_lock();



	if (!attrs[NL80211_ATTR_WIPHY] &&

	    !attrs[NL80211_ATTR_IFINDEX])

	    !attrs[NL80211_ATTR_IFINDEX] &&

	    !attrs[NL80211_ATTR_WDEV])

		return ERR_PTR(-EINVAL);



	if (attrs[NL80211_ATTR_WIPHY])

		rdev = cfg80211_rdev_by_wiphy_idx(

				nla_get_u32(attrs[NL80211_ATTR_WIPHY]));



	if (attrs[NL80211_ATTR_WDEV]) {

		u64 wdev_id = nla_get_u64(attrs[NL80211_ATTR_WDEV]);

		struct wireless_dev *wdev;

		bool found = false;



		tmp = cfg80211_rdev_by_wiphy_idx(wdev_id >> 32);

		if (tmp) {

			/* make sure wdev exists */

			mutex_lock(&tmp->devlist_mtx);

			list_for_each_entry(wdev, &tmp->wdev_list, list) {

				if (wdev->identifier != (u32)wdev_id)

					continue;

				found = true;

				break;

			}

			mutex_unlock(&tmp->devlist_mtx);



			if (!found)

				tmp = NULL;



			if (rdev && tmp != rdev)

				return ERR_PTR(-EINVAL);

			rdev = tmp;

		}

	}



	if (attrs[NL80211_ATTR_IFINDEX]) {

		int ifindex = nla_get_u32(attrs[NL80211_ATTR_IFINDEX]);

		netdev = dev_get_by_index(netns, ifindex);
@@ -294,6 +353,7 @@ static const struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] = { 
	[NL80211_ATTR_NOACK_MAP] = { .type = NLA_U16 },

	[NL80211_ATTR_INACTIVITY_TIMEOUT] = { .type = NLA_U16 },

	[NL80211_ATTR_BG_SCAN_PERIOD] = { .type = NLA_U16 },

	[NL80211_ATTR_WDEV] = { .type = NLA_U64 },

};



/* policy for the key attributes */
@@ -1674,6 +1734,8 @@ static int nl80211_send_iface(struct sk_buff *msg, u32 pid, u32 seq, int flags, 
			      struct net_device *dev)

{

	void *hdr;

	u64 wdev_id = (u64)dev->ieee80211_ptr->identifier |

		      ((u64)rdev->wiphy_idx << 32);



	hdr = nl80211hdr_put(msg, pid, seq, flags, NL80211_CMD_NEW_INTERFACE);

	if (!hdr)
@@ -1684,6 +1746,7 @@ static int nl80211_send_iface(struct sk_buff *msg, u32 pid, u32 seq, int flags, 
	    nla_put_string(msg, NL80211_ATTR_IFNAME, dev->name) ||

	    nla_put_u32(msg, NL80211_ATTR_IFTYPE,

			dev->ieee80211_ptr->iftype) ||

	    nla_put_u64(msg, NL80211_ATTR_WDEV, wdev_id) ||

	    nla_put_u32(msg, NL80211_ATTR_GENERATION,

			rdev->devlist_generation ^

			(cfg80211_rdev_list_generation << 2)))
@@ -1724,7 +1787,7 @@ static int nl80211_dump_interface(struct sk_buff *skb, struct netlink_callback * 
		if_idx = 0;



		mutex_lock(&rdev->devlist_mtx);

		list_for_each_entry(wdev, &rdev->netdev_list, list) {

		list_for_each_entry(wdev, &rdev->wdev_list, list) {

			if (if_idx < if_start) {

				if_idx++;

				continue;
@@ -2350,7 +2413,7 @@ static bool nl80211_get_ap_channel(struct cfg80211_registered_device *rdev, 


	mutex_lock(&rdev->devlist_mtx);



	list_for_each_entry(wdev, &rdev->netdev_list, list) {

	list_for_each_entry(wdev, &rdev->wdev_list, list) {

		if (wdev->iftype != NL80211_IFTYPE_AP &&

		    wdev->iftype != NL80211_IFTYPE_P2P_GO)

			continue;
@@ -6660,8 +6723,8 @@ static int nl80211_pre_doit(struct genl_ops *ops, struct sk_buff *skb, 
			    struct genl_info *info)

{

	struct cfg80211_registered_device *rdev;

	struct wireless_dev *wdev;

	struct net_device *dev;

	int err;

	bool rtnl = ops->internal_flags & NL80211_FLAG_NEED_RTNL;



	if (rtnl)
@@ -6676,21 +6739,39 @@ static int nl80211_pre_doit(struct genl_ops *ops, struct sk_buff *skb, 
		}

		info->user_ptr[0] = rdev;

	} else if (ops->internal_flags & NL80211_FLAG_NEED_NETDEV) {

		err = get_rdev_dev_by_ifindex(genl_info_net(info), info->attrs,

					      &rdev, &dev);

		if (err) {

		mutex_lock(&cfg80211_mutex);

		wdev = __cfg80211_wdev_from_attrs(genl_info_net(info),

						  info->attrs);

		if (IS_ERR(wdev)) {

			mutex_unlock(&cfg80211_mutex);

			if (rtnl)

				rtnl_unlock();

			return err;

			return PTR_ERR(wdev);

		}



		if (!wdev->netdev) {

			mutex_unlock(&cfg80211_mutex);

			if (rtnl)

				rtnl_unlock();

			return -EINVAL;

		}



		dev = wdev->netdev;

		rdev = wiphy_to_dev(wdev->wiphy);



		if (ops->internal_flags & NL80211_FLAG_CHECK_NETDEV_UP &&

		    !netif_running(dev)) {

			cfg80211_unlock_rdev(rdev);

			dev_put(dev);

			mutex_unlock(&cfg80211_mutex);

			if (rtnl)

				rtnl_unlock();

			return -ENETDOWN;

		}



		dev_hold(dev);

		cfg80211_lock_rdev(rdev);



		mutex_unlock(&cfg80211_mutex);



		info->user_ptr[0] = rdev;

		info->user_ptr[1] = dev;

	}
@@ -8483,7 +8564,7 @@ static int nl80211_netlink_notify(struct notifier_block * nb, 
	rcu_read_lock();



	list_for_each_entry_rcu(rdev, &cfg80211_rdev_list, list) {

		list_for_each_entry_rcu(wdev, &rdev->netdev_list, list)

		list_for_each_entry_rcu(wdev, &rdev->wdev_list, list)

			cfg80211_mlme_unregister_socket(wdev, notify->pid);

		if (rdev->ap_beacons_nlpid == notify->pid)

			rdev->ap_beacons_nlpid = 0;