Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 550 insertions, 0 deletions

diff --git a/net/batman-adv/bat_v_elp.c b/net/batman-adv/bat_v_elp.c
new file mode 100644
index 0000000000..1d704574e6
--- /dev/null
+++ b/net/batman-adv/bat_v_elp.c
@@ -0,0 +1,550 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) B.A.T.M.A.N. contributors:
+ *
+ * Linus Lüssing, Marek Lindner
+ */
+
+#include "bat_v_elp.h"
+#include "main.h"
+
+#include <linux/atomic.h>
+#include <linux/bitops.h>
+#include <linux/byteorder/generic.h>
+#include <linux/container_of.h>
+#include <linux/errno.h>
+#include <linux/etherdevice.h>
+#include <linux/ethtool.h>
+#include <linux/gfp.h>
+#include <linux/if_ether.h>
+#include <linux/jiffies.h>
+#include <linux/kref.h>
+#include <linux/minmax.h>
+#include <linux/netdevice.h>
+#include <linux/nl80211.h>
+#include <linux/random.h>
+#include <linux/rculist.h>
+#include <linux/rcupdate.h>
+#include <linux/rtnetlink.h>
+#include <linux/skbuff.h>
+#include <linux/stddef.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/workqueue.h>
+#include <net/cfg80211.h>
+#include <uapi/linux/batadv_packet.h>
+
+#include "bat_algo.h"
+#include "bat_v_ogm.h"
+#include "hard-interface.h"
+#include "log.h"
+#include "originator.h"
+#include "routing.h"
+#include "send.h"
+
+/**
+ * batadv_v_elp_start_timer() - restart timer for ELP periodic work
+ * @hard_iface: the interface for which the timer has to be reset
+ */
+static void batadv_v_elp_start_timer(struct batadv_hard_iface *hard_iface)
+{
+	unsigned int msecs;
+
+	msecs = atomic_read(&hard_iface->bat_v.elp_interval) - BATADV_JITTER;
+	msecs += get_random_u32_below(2 * BATADV_JITTER);
+
+	queue_delayed_work(batadv_event_workqueue, &hard_iface->bat_v.elp_wq,
+			   msecs_to_jiffies(msecs));
+}
+
+/**
+ * batadv_v_elp_get_throughput() - get the throughput towards a neighbour
+ * @neigh: the neighbour for which the throughput has to be obtained
+ *
+ * Return: The throughput towards the given neighbour in multiples of 100kpbs
+ *         (a value of '1' equals 0.1Mbps, '10' equals 1Mbps, etc).
+ */
+static u32 batadv_v_elp_get_throughput(struct batadv_hardif_neigh_node *neigh)
+{
+	struct batadv_hard_iface *hard_iface = neigh->if_incoming;
+	struct ethtool_link_ksettings link_settings;
+	struct net_device *real_netdev;
+	struct station_info sinfo;
+	u32 throughput;
+	int ret;
+
+	/* if the user specified a customised value for this interface, then
+	 * return it directly
+	 */
+	throughput =  atomic_read(&hard_iface->bat_v.throughput_override);
+	if (throughput != 0)
+		return throughput;
+
+	/* if this is a wireless device, then ask its throughput through
+	 * cfg80211 API
+	 */
+	if (batadv_is_wifi_hardif(hard_iface)) {
+		if (!batadv_is_cfg80211_hardif(hard_iface))
+			/* unsupported WiFi driver version */
+			goto default_throughput;
+
+		real_netdev = batadv_get_real_netdev(hard_iface->net_dev);
+		if (!real_netdev)
+			goto default_throughput;
+
+		ret = cfg80211_get_station(real_netdev, neigh->addr, &sinfo);
+
+		if (!ret) {
+			/* free the TID stats immediately */
+			cfg80211_sinfo_release_content(&sinfo);
+		}
+
+		dev_put(real_netdev);
+		if (ret == -ENOENT) {
+			/* Node is not associated anymore! It would be
+			 * possible to delete this neighbor. For now set
+			 * the throughput metric to 0.
+			 */
+			return 0;
+		}
+		if (ret)
+			goto default_throughput;
+
+		if (sinfo.filled & BIT(NL80211_STA_INFO_EXPECTED_THROUGHPUT))
+			return sinfo.expected_throughput / 100;
+
+		/* try to estimate the expected throughput based on reported tx
+		 * rates
+		 */
+		if (sinfo.filled & BIT(NL80211_STA_INFO_TX_BITRATE))
+			return cfg80211_calculate_bitrate(&sinfo.txrate) / 3;
+
+		goto default_throughput;
+	}
+
+	/* if not a wifi interface, check if this device provides data via
+	 * ethtool (e.g. an Ethernet adapter)
+	 */
+	rtnl_lock();
+	ret = __ethtool_get_link_ksettings(hard_iface->net_dev, &link_settings);
+	rtnl_unlock();
+	if (ret == 0) {
+		/* link characteristics might change over time */
+		if (link_settings.base.duplex == DUPLEX_FULL)
+			hard_iface->bat_v.flags |= BATADV_FULL_DUPLEX;
+		else
+			hard_iface->bat_v.flags &= ~BATADV_FULL_DUPLEX;
+
+		throughput = link_settings.base.speed;
+		if (throughput && throughput != SPEED_UNKNOWN)
+			return throughput * 10;
+	}
+
+default_throughput:
+	if (!(hard_iface->bat_v.flags & BATADV_WARNING_DEFAULT)) {
+		batadv_info(hard_iface->soft_iface,
+			    "WiFi driver or ethtool info does not provide information about link speeds on interface %s, therefore defaulting to hardcoded throughput values of %u.%1u Mbps. Consider overriding the throughput manually or checking your driver.\n",
+			    hard_iface->net_dev->name,
+			    BATADV_THROUGHPUT_DEFAULT_VALUE / 10,
+			    BATADV_THROUGHPUT_DEFAULT_VALUE % 10);
+		hard_iface->bat_v.flags |= BATADV_WARNING_DEFAULT;
+	}
+
+	/* if none of the above cases apply, return the base_throughput */
+	return BATADV_THROUGHPUT_DEFAULT_VALUE;
+}
+
+/**
+ * batadv_v_elp_throughput_metric_update() - worker updating the throughput
+ *  metric of a single hop neighbour
+ * @work: the work queue item
+ */
+void batadv_v_elp_throughput_metric_update(struct work_struct *work)
+{
+	struct batadv_hardif_neigh_node_bat_v *neigh_bat_v;
+	struct batadv_hardif_neigh_node *neigh;
+
+	neigh_bat_v = container_of(work, struct batadv_hardif_neigh_node_bat_v,
+				   metric_work);
+	neigh = container_of(neigh_bat_v, struct batadv_hardif_neigh_node,
+			     bat_v);
+
+	ewma_throughput_add(&neigh->bat_v.throughput,
+			    batadv_v_elp_get_throughput(neigh));
+
+	/* decrement refcounter to balance increment performed before scheduling
+	 * this task
+	 */
+	batadv_hardif_neigh_put(neigh);
+}
+
+/**
+ * batadv_v_elp_wifi_neigh_probe() - send link probing packets to a neighbour
+ * @neigh: the neighbour to probe
+ *
+ * Sends a predefined number of unicast wifi packets to a given neighbour in
+ * order to trigger the throughput estimation on this link by the RC algorithm.
+ * Packets are sent only if there is not enough payload unicast traffic towards
+ * this neighbour..
+ *
+ * Return: True on success and false in case of error during skb preparation.
+ */
+static bool
+batadv_v_elp_wifi_neigh_probe(struct batadv_hardif_neigh_node *neigh)
+{
+	struct batadv_hard_iface *hard_iface = neigh->if_incoming;
+	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
+	unsigned long last_tx_diff;
+	struct sk_buff *skb;
+	int probe_len, i;
+	int elp_skb_len;
+
+	/* this probing routine is for Wifi neighbours only */
+	if (!batadv_is_wifi_hardif(hard_iface))
+		return true;
+
+	/* probe the neighbor only if no unicast packets have been sent
+	 * to it in the last 100 milliseconds: this is the rate control
+	 * algorithm sampling interval (minstrel). In this way, if not
+	 * enough traffic has been sent to the neighbor, batman-adv can
+	 * generate 2 probe packets and push the RC algorithm to perform
+	 * the sampling
+	 */
+	last_tx_diff = jiffies_to_msecs(jiffies - neigh->bat_v.last_unicast_tx);
+	if (last_tx_diff <= BATADV_ELP_PROBE_MAX_TX_DIFF)
+		return true;
+
+	probe_len = max_t(int, sizeof(struct batadv_elp_packet),
+			  BATADV_ELP_MIN_PROBE_SIZE);
+
+	for (i = 0; i < BATADV_ELP_PROBES_PER_NODE; i++) {
+		elp_skb_len = hard_iface->bat_v.elp_skb->len;
+		skb = skb_copy_expand(hard_iface->bat_v.elp_skb, 0,
+				      probe_len - elp_skb_len,
+				      GFP_ATOMIC);
+		if (!skb)
+			return false;
+
+		/* Tell the skb to get as big as the allocated space (we want
+		 * the packet to be exactly of that size to make the link
+		 * throughput estimation effective.
+		 */
+		skb_put_zero(skb, probe_len - hard_iface->bat_v.elp_skb->len);
+
+		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+			   "Sending unicast (probe) ELP packet on interface %s to %pM\n",
+			   hard_iface->net_dev->name, neigh->addr);
+
+		batadv_send_skb_packet(skb, hard_iface, neigh->addr);
+	}
+
+	return true;
+}
+
+/**
+ * batadv_v_elp_periodic_work() - ELP periodic task per interface
+ * @work: work queue item
+ *
+ * Emits broadcast ELP messages in regular intervals.
+ */
+static void batadv_v_elp_periodic_work(struct work_struct *work)
+{
+	struct batadv_hardif_neigh_node *hardif_neigh;
+	struct batadv_hard_iface *hard_iface;
+	struct batadv_hard_iface_bat_v *bat_v;
+	struct batadv_elp_packet *elp_packet;
+	struct batadv_priv *bat_priv;
+	struct sk_buff *skb;
+	u32 elp_interval;
+	bool ret;
+
+	bat_v = container_of(work, struct batadv_hard_iface_bat_v, elp_wq.work);
+	hard_iface = container_of(bat_v, struct batadv_hard_iface, bat_v);
+	bat_priv = netdev_priv(hard_iface->soft_iface);
+
+	if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING)
+		goto out;
+
+	/* we are in the process of shutting this interface down */
+	if (hard_iface->if_status == BATADV_IF_NOT_IN_USE ||
+	    hard_iface->if_status == BATADV_IF_TO_BE_REMOVED)
+		goto out;
+
+	/* the interface was enabled but may not be ready yet */
+	if (hard_iface->if_status != BATADV_IF_ACTIVE)
+		goto restart_timer;
+
+	skb = skb_copy(hard_iface->bat_v.elp_skb, GFP_ATOMIC);
+	if (!skb)
+		goto restart_timer;
+
+	elp_packet = (struct batadv_elp_packet *)skb->data;
+	elp_packet->seqno = htonl(atomic_read(&hard_iface->bat_v.elp_seqno));
+	elp_interval = atomic_read(&hard_iface->bat_v.elp_interval);
+	elp_packet->elp_interval = htonl(elp_interval);
+
+	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+		   "Sending broadcast ELP packet on interface %s, seqno %u\n",
+		   hard_iface->net_dev->name,
+		   atomic_read(&hard_iface->bat_v.elp_seqno));
+
+	batadv_send_broadcast_skb(skb, hard_iface);
+
+	atomic_inc(&hard_iface->bat_v.elp_seqno);
+
+	/* The throughput metric is updated on each sent packet. This way, if a
+	 * node is dead and no longer sends packets, batman-adv is still able to
+	 * react timely to its death.
+	 *
+	 * The throughput metric is updated by following these steps:
+	 * 1) if the hard_iface is wifi => send a number of unicast ELPs for
+	 *    probing/sampling to each neighbor
+	 * 2) update the throughput metric value of each neighbor (note that the
+	 *    value retrieved in this step might be 100ms old because the
+	 *    probing packets at point 1) could still be in the HW queue)
+	 */
+	rcu_read_lock();
+	hlist_for_each_entry_rcu(hardif_neigh, &hard_iface->neigh_list, list) {
+		if (!batadv_v_elp_wifi_neigh_probe(hardif_neigh))
+			/* if something goes wrong while probing, better to stop
+			 * sending packets immediately and reschedule the task
+			 */
+			break;
+
+		if (!kref_get_unless_zero(&hardif_neigh->refcount))
+			continue;
+
+		/* Reading the estimated throughput from cfg80211 is a task that
+		 * may sleep and that is not allowed in an rcu protected
+		 * context. Therefore schedule a task for that.
+		 */
+		ret = queue_work(batadv_event_workqueue,
+				 &hardif_neigh->bat_v.metric_work);
+
+		if (!ret)
+			batadv_hardif_neigh_put(hardif_neigh);
+	}
+	rcu_read_unlock();
+
+restart_timer:
+	batadv_v_elp_start_timer(hard_iface);
+out:
+	return;
+}
+
+/**
+ * batadv_v_elp_iface_enable() - setup the ELP interface private resources
+ * @hard_iface: interface for which the data has to be prepared
+ *
+ * Return: 0 on success or a -ENOMEM in case of failure.
+ */
+int batadv_v_elp_iface_enable(struct batadv_hard_iface *hard_iface)
+{
+	static const size_t tvlv_padding = sizeof(__be32);
+	struct batadv_elp_packet *elp_packet;
+	unsigned char *elp_buff;
+	u32 random_seqno;
+	size_t size;
+	int res = -ENOMEM;
+
+	size = ETH_HLEN + NET_IP_ALIGN + BATADV_ELP_HLEN + tvlv_padding;
+	hard_iface->bat_v.elp_skb = dev_alloc_skb(size);
+	if (!hard_iface->bat_v.elp_skb)
+		goto out;
+
+	skb_reserve(hard_iface->bat_v.elp_skb, ETH_HLEN + NET_IP_ALIGN);
+	elp_buff = skb_put_zero(hard_iface->bat_v.elp_skb,
+				BATADV_ELP_HLEN + tvlv_padding);
+	elp_packet = (struct batadv_elp_packet *)elp_buff;
+
+	elp_packet->packet_type = BATADV_ELP;
+	elp_packet->version = BATADV_COMPAT_VERSION;
+
+	/* randomize initial seqno to avoid collision */
+	get_random_bytes(&random_seqno, sizeof(random_seqno));
+	atomic_set(&hard_iface->bat_v.elp_seqno, random_seqno);
+
+	/* assume full-duplex by default */
+	hard_iface->bat_v.flags |= BATADV_FULL_DUPLEX;
+
+	/* warn the user (again) if there is no throughput data is available */
+	hard_iface->bat_v.flags &= ~BATADV_WARNING_DEFAULT;
+
+	if (batadv_is_wifi_hardif(hard_iface))
+		hard_iface->bat_v.flags &= ~BATADV_FULL_DUPLEX;
+
+	INIT_DELAYED_WORK(&hard_iface->bat_v.elp_wq,
+			  batadv_v_elp_periodic_work);
+	batadv_v_elp_start_timer(hard_iface);
+	res = 0;
+
+out:
+	return res;
+}
+
+/**
+ * batadv_v_elp_iface_disable() - release ELP interface private resources
+ * @hard_iface: interface for which the resources have to be released
+ */
+void batadv_v_elp_iface_disable(struct batadv_hard_iface *hard_iface)
+{
+	cancel_delayed_work_sync(&hard_iface->bat_v.elp_wq);
+
+	dev_kfree_skb(hard_iface->bat_v.elp_skb);
+	hard_iface->bat_v.elp_skb = NULL;
+}
+
+/**
+ * batadv_v_elp_iface_activate() - update the ELP buffer belonging to the given
+ *  hard-interface
+ * @primary_iface: the new primary interface
+ * @hard_iface: interface holding the to-be-updated buffer
+ */
+void batadv_v_elp_iface_activate(struct batadv_hard_iface *primary_iface,
+				 struct batadv_hard_iface *hard_iface)
+{
+	struct batadv_elp_packet *elp_packet;
+	struct sk_buff *skb;
+
+	if (!hard_iface->bat_v.elp_skb)
+		return;
+
+	skb = hard_iface->bat_v.elp_skb;
+	elp_packet = (struct batadv_elp_packet *)skb->data;
+	ether_addr_copy(elp_packet->orig,
+			primary_iface->net_dev->dev_addr);
+}
+
+/**
+ * batadv_v_elp_primary_iface_set() - change internal data to reflect the new
+ *  primary interface
+ * @primary_iface: the new primary interface
+ */
+void batadv_v_elp_primary_iface_set(struct batadv_hard_iface *primary_iface)
+{
+	struct batadv_hard_iface *hard_iface;
+
+	/* update orig field of every elp iface belonging to this mesh */
+	rcu_read_lock();
+	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
+		if (primary_iface->soft_iface != hard_iface->soft_iface)
+			continue;
+
+		batadv_v_elp_iface_activate(primary_iface, hard_iface);
+	}
+	rcu_read_unlock();
+}
+
+/**
+ * batadv_v_elp_neigh_update() - update an ELP neighbour node
+ * @bat_priv: the bat priv with all the soft interface information
+ * @neigh_addr: the neighbour interface address
+ * @if_incoming: the interface the packet was received through
+ * @elp_packet: the received ELP packet
+ *
+ * Updates the ELP neighbour node state with the data received within the new
+ * ELP packet.
+ */
+static void batadv_v_elp_neigh_update(struct batadv_priv *bat_priv,
+				      u8 *neigh_addr,
+				      struct batadv_hard_iface *if_incoming,
+				      struct batadv_elp_packet *elp_packet)
+
+{
+	struct batadv_neigh_node *neigh;
+	struct batadv_orig_node *orig_neigh;
+	struct batadv_hardif_neigh_node *hardif_neigh;
+	s32 seqno_diff;
+	s32 elp_latest_seqno;
+
+	orig_neigh = batadv_v_ogm_orig_get(bat_priv, elp_packet->orig);
+	if (!orig_neigh)
+		return;
+
+	neigh = batadv_neigh_node_get_or_create(orig_neigh,
+						if_incoming, neigh_addr);
+	if (!neigh)
+		goto orig_free;
+
+	hardif_neigh = batadv_hardif_neigh_get(if_incoming, neigh_addr);
+	if (!hardif_neigh)
+		goto neigh_free;
+
+	elp_latest_seqno = hardif_neigh->bat_v.elp_latest_seqno;
+	seqno_diff = ntohl(elp_packet->seqno) - elp_latest_seqno;
+
+	/* known or older sequence numbers are ignored. However always adopt
+	 * if the router seems to have been restarted.
+	 */
+	if (seqno_diff < 1 && seqno_diff > -BATADV_ELP_MAX_AGE)
+		goto hardif_free;
+
+	neigh->last_seen = jiffies;
+	hardif_neigh->last_seen = jiffies;
+	hardif_neigh->bat_v.elp_latest_seqno = ntohl(elp_packet->seqno);
+	hardif_neigh->bat_v.elp_interval = ntohl(elp_packet->elp_interval);
+
+hardif_free:
+	batadv_hardif_neigh_put(hardif_neigh);
+neigh_free:
+	batadv_neigh_node_put(neigh);
+orig_free:
+	batadv_orig_node_put(orig_neigh);
+}
+
+/**
+ * batadv_v_elp_packet_recv() - main ELP packet handler
+ * @skb: the received packet
+ * @if_incoming: the interface this packet was received through
+ *
+ * Return: NET_RX_SUCCESS and consumes the skb if the packet was properly
+ * processed or NET_RX_DROP in case of failure.
+ */
+int batadv_v_elp_packet_recv(struct sk_buff *skb,
+			     struct batadv_hard_iface *if_incoming)
+{
+	struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
+	struct batadv_elp_packet *elp_packet;
+	struct batadv_hard_iface *primary_if;
+	struct ethhdr *ethhdr;
+	bool res;
+	int ret = NET_RX_DROP;
+
+	res = batadv_check_management_packet(skb, if_incoming, BATADV_ELP_HLEN);
+	if (!res)
+		goto free_skb;
+
+	ethhdr = eth_hdr(skb);
+	if (batadv_is_my_mac(bat_priv, ethhdr->h_source))
+		goto free_skb;
+
+	/* did we receive a B.A.T.M.A.N. V ELP packet on an interface
+	 * that does not have B.A.T.M.A.N. V ELP enabled ?
+	 */
+	if (strcmp(bat_priv->algo_ops->name, "BATMAN_V") != 0)
+		goto free_skb;
+
+	elp_packet = (struct batadv_elp_packet *)skb->data;
+
+	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+		   "Received ELP packet from %pM seqno %u ORIG: %pM\n",
+		   ethhdr->h_source, ntohl(elp_packet->seqno),
+		   elp_packet->orig);
+
+	primary_if = batadv_primary_if_get_selected(bat_priv);
+	if (!primary_if)
+		goto free_skb;
+
+	batadv_v_elp_neigh_update(bat_priv, ethhdr->h_source, if_incoming,
+				  elp_packet);
+
+	ret = NET_RX_SUCCESS;
+	batadv_hardif_put(primary_if);
+
+free_skb:
+	if (ret == NET_RX_SUCCESS)
+		consume_skb(skb);
+	else
+		kfree_skb(skb);
+
+	return ret;
+}