Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

Pull networking updates from David Miller:
 "Highlights (1721 non-merge commits, this has to be a record of some
  sort):

   1) Add 'random' mode to team driver, from Jiri Pirko and Eric
      Dumazet.

   2) Make it so that any driver that supports configuration of multiple
      MAC addresses can provide the forwarding database add and del
      calls by providing a default implementation and hooking that up if
      the driver doesn't have an explicit set of handlers.  From Vlad
      Yasevich.

   3) Support GSO segmentation over tunnels and other encapsulating
      devices such as VXLAN, from Pravin B Shelar.

   4) Support L2 GRE tunnels in the flow dissector, from Michael Dalton.

   5) Implement Tail Loss Probe (TLP) detection in TCP, from Nandita
      Dukkipati.

   6) In the PHY layer, allow supporting wake-on-lan in situations where
      the PHY registers have to be written for it to be configured.

      Use it to support wake-on-lan in mv643xx_eth.

      From Michael Stapelberg.

   7) Significantly improve firewire IPV6 support, from YOSHIFUJI
      Hideaki.

   8) Allow multiple packets to be sent in a single transmission using
      network coding in batman-adv, from Martin Hundebøll.

   9) Add support for T5 cxgb4 chips, from Santosh Rastapur.

  10) Generalize the VXLAN forwarding tables so that there is more
      flexibility in configurating various aspects of the endpoints.
      From David Stevens.

  11) Support RSS and TSO in hardware over GRE tunnels in bxn2x driver,
      from Dmitry Kravkov.

  12) Zero copy support in nfnelink_queue, from Eric Dumazet and Pablo
      Neira Ayuso.

  13) Start adding networking selftests.

  14) In situations of overload on the same AF_PACKET fanout socket, or
      per-cpu packet receive queue, minimize drop by distributing the
      load to other cpus/fanouts.  From Willem de Bruijn and Eric
      Dumazet.

  15) Add support for new payload offset BPF instruction, from Daniel
      Borkmann.

  16) Convert several drivers over to mdoule_platform_driver(), from
      Sachin Kamat.

  17) Provide a minimal BPF JIT image disassembler userspace tool, from
      Daniel Borkmann.

  18) Rewrite F-RTO implementation in TCP to match the final
      specification of it in RFC4138 and RFC5682.  From Yuchung Cheng.

  19) Provide netlink socket diag of netlink sockets ("Yo dawg, I hear
      you like netlink, so I implemented netlink dumping of netlink
      sockets.") From Andrey Vagin.

  20) Remove ugly passing of rtnetlink attributes into rtnl_doit
      functions, from Thomas Graf.

  21) Allow userspace to be able to see if a configuration change occurs
      in the middle of an address or device list dump, from Nicolas
      Dichtel.

  22) Support RFC3168 ECN protection for ipv6 fragments, from Hannes
      Frederic Sowa.

  23) Increase accuracy of packet length used by packet scheduler, from
      Jason Wang.

  24) Beginning set of changes to make ipv4/ipv6 fragment handling more
      scalable and less susceptible to overload and locking contention,
      from Jesper Dangaard Brouer.

  25) Get rid of using non-type-safe NLMSG_* macros and use nlmsg_*()
      instead.  From Hong Zhiguo.

  26) Optimize route usage in IPVS by avoiding reference counting where
      possible, from Julian Anastasov.

  27) Convert IPVS schedulers to RCU, also from Julian Anastasov.

  28) Support cpu fanouts in xt_NFQUEUE netfilter target, from Holger
      Eitzenberger.

  29) Network namespace support for nf_log, ebt_log, xt_LOG, ipt_ULOG,
      nfnetlink_log, and nfnetlink_queue.  From Gao feng.

  30) Implement RFC3168 ECN protection, from Hannes Frederic Sowa.

  31) Support several new r8169 chips, from Hayes Wang.

  32) Support tokenized interface identifiers in ipv6, from Daniel
      Borkmann.

  33) Use usbnet_link_change() helper in USB net driver, from Ming Lei.

  34) Add 802.1ad vlan offload support, from Patrick McHardy.

  35) Support mmap() based netlink communication, also from Patrick
      McHardy.

  36) Support HW timestamping in mlx4 driver, from Amir Vadai.

  37) Rationalize AF_PACKET packet timestamping when transmitting, from
      Willem de Bruijn and Daniel Borkmann.

  38) Bring parity to what's provided by /proc/net/packet socket dumping
      and the info provided by netlink socket dumping of AF_PACKET
      sockets.  From Nicolas Dichtel.

  39) Fix peeking beyond zero sized SKBs in AF_UNIX, from Benjamin
      Poirier"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1722 commits)
  filter: fix va_list build error
  af_unix: fix a fatal race with bit fields
  bnx2x: Prevent memory leak when cnic is absent
  bnx2x: correct reading of speed capabilities
  net: sctp: attribute printl with __printf for gcc fmt checks
  netlink: kconfig: move mmap i/o into netlink kconfig
  netpoll: convert mutex into a semaphore
  netlink: Fix skb ref counting.
  net_sched: act_ipt forward compat with xtables
  mlx4_en: fix a build error on 32bit arches
  Revert "bnx2x: allow nvram test to run when device is down"
  bridge: avoid OOPS if root port not found
  drivers: net: cpsw: fix kernel warn on cpsw irq enable
  sh_eth: use random MAC address if no valid one supplied
  3c509.c: call SET_NETDEV_DEV for all device types (ISA/ISAPnP/EISA)
  tg3: fix to append hardware time stamping flags
  unix/stream: fix peeking with an offset larger than data in queue
  unix/dgram: fix peeking with an offset larger than data in queue
  unix/dgram: peek beyond 0-sized skbs
  openvswitch: Remove unneeded ovs_netdev_get_ifindex()
  ...

1 files changed, 64 insertions, 51 deletions

diff --git a/net/netfilter/ipvs/ip_vs_lblc.c b/net/netfilter/ipvs/ip_vs_lblc.c
index fdd89b9564ea..5ea26bd87743 100644
--- a/net/netfilter/ipvs/ip_vs_lblc.c
+++ b/net/netfilter/ipvs/ip_vs_lblc.c
@@ -90,11 +90,12 @@
  *      IP address and its destination server
  */
 struct ip_vs_lblc_entry {
-	struct list_head        list;
+	struct hlist_node	list;
 	int			af;		/* address family */
 	union nf_inet_addr      addr;           /* destination IP address */
-	struct ip_vs_dest       *dest;          /* real server (cache) */
+	struct ip_vs_dest __rcu	*dest;          /* real server (cache) */
 	unsigned long           lastuse;        /* last used time */
+	struct rcu_head		rcu_head;
 };
 
 
@@ -102,12 +103,14 @@ struct ip_vs_lblc_entry {
  *      IPVS lblc hash table
  */
 struct ip_vs_lblc_table {
-	struct list_head        bucket[IP_VS_LBLC_TAB_SIZE];  /* hash bucket */
+	struct rcu_head		rcu_head;
+	struct hlist_head	bucket[IP_VS_LBLC_TAB_SIZE];  /* hash bucket */
+	struct timer_list       periodic_timer; /* collect stale entries */
 	atomic_t                entries;        /* number of entries */
 	int                     max_size;       /* maximum size of entries */
-	struct timer_list       periodic_timer; /* collect stale entries */
 	int                     rover;          /* rover for expire check */
 	int                     counter;        /* counter for no expire */
+	bool			dead;
 };
 
 
@@ -129,13 +132,16 @@ static ctl_table vs_vars_table[] = {
 
 static inline void ip_vs_lblc_free(struct ip_vs_lblc_entry *en)
 {
-	list_del(&en->list);
+	struct ip_vs_dest *dest;
+
+	hlist_del_rcu(&en->list);
 	/*
 	 * We don't kfree dest because it is referred either by its service
 	 * or the trash dest list.
 	 */
-	atomic_dec(&en->dest->refcnt);
-	kfree(en);
+	dest = rcu_dereference_protected(en->dest, 1);
+	ip_vs_dest_put(dest);
+	kfree_rcu(en, rcu_head);
 }
 
 
@@ -165,15 +171,12 @@ ip_vs_lblc_hash(struct ip_vs_lblc_table *tbl, struct ip_vs_lblc_entry *en)
 {
 	unsigned int hash = ip_vs_lblc_hashkey(en->af, &en->addr);
 
-	list_add(&en->list, &tbl->bucket[hash]);
+	hlist_add_head_rcu(&en->list, &tbl->bucket[hash]);
 	atomic_inc(&tbl->entries);
 }
 
 
-/*
- *  Get ip_vs_lblc_entry associated with supplied parameters. Called under read
- *  lock
- */
+/* Get ip_vs_lblc_entry associated with supplied parameters. */
 static inline struct ip_vs_lblc_entry *
 ip_vs_lblc_get(int af, struct ip_vs_lblc_table *tbl,
 	       const union nf_inet_addr *addr)
@@ -181,7 +184,7 @@ ip_vs_lblc_get(int af, struct ip_vs_lblc_table *tbl,
 	unsigned int hash = ip_vs_lblc_hashkey(af, addr);
 	struct ip_vs_lblc_entry *en;
 
-	list_for_each_entry(en, &tbl->bucket[hash], list)
+	hlist_for_each_entry_rcu(en, &tbl->bucket[hash], list)
 		if (ip_vs_addr_equal(af, &en->addr, addr))
 			return en;
 
@@ -191,7 +194,7 @@ ip_vs_lblc_get(int af, struct ip_vs_lblc_table *tbl,
 
 /*
  * Create or update an ip_vs_lblc_entry, which is a mapping of a destination IP
- * address to a server. Called under write lock.
+ * address to a server. Called under spin lock.
  */
 static inline struct ip_vs_lblc_entry *
 ip_vs_lblc_new(struct ip_vs_lblc_table *tbl, const union nf_inet_addr *daddr,
@@ -209,14 +212,20 @@ ip_vs_lblc_new(struct ip_vs_lblc_table *tbl, const union nf_inet_addr *daddr,
 		ip_vs_addr_copy(dest->af, &en->addr, daddr);
 		en->lastuse = jiffies;
 
-		atomic_inc(&dest->refcnt);
-		en->dest = dest;
+		ip_vs_dest_hold(dest);
+		RCU_INIT_POINTER(en->dest, dest);
 
 		ip_vs_lblc_hash(tbl, en);
-	} else if (en->dest != dest) {
-		atomic_dec(&en->dest->refcnt);
-		atomic_inc(&dest->refcnt);
-		en->dest = dest;
+	} else {
+		struct ip_vs_dest *old_dest;
+
+		old_dest = rcu_dereference_protected(en->dest, 1);
+		if (old_dest != dest) {
+			ip_vs_dest_put(old_dest);
+			ip_vs_dest_hold(dest);
+			/* No ordering constraints for refcnt */
+			RCU_INIT_POINTER(en->dest, dest);
+		}
 	}
 
 	return en;
@@ -226,17 +235,22 @@ ip_vs_lblc_new(struct ip_vs_lblc_table *tbl, const union nf_inet_addr *daddr,
 /*
  *      Flush all the entries of the specified table.
  */
-static void ip_vs_lblc_flush(struct ip_vs_lblc_table *tbl)
+static void ip_vs_lblc_flush(struct ip_vs_service *svc)
 {
-	struct ip_vs_lblc_entry *en, *nxt;
+	struct ip_vs_lblc_table *tbl = svc->sched_data;
+	struct ip_vs_lblc_entry *en;
+	struct hlist_node *next;
 	int i;
 
+	spin_lock_bh(&svc->sched_lock);
+	tbl->dead = 1;
 	for (i=0; i<IP_VS_LBLC_TAB_SIZE; i++) {
-		list_for_each_entry_safe(en, nxt, &tbl->bucket[i], list) {
+		hlist_for_each_entry_safe(en, next, &tbl->bucket[i], list) {
 			ip_vs_lblc_free(en);
 			atomic_dec(&tbl->entries);
 		}
 	}
+	spin_unlock_bh(&svc->sched_lock);
 }
 
 static int sysctl_lblc_expiration(struct ip_vs_service *svc)
@@ -252,15 +266,16 @@ static int sysctl_lblc_expiration(struct ip_vs_service *svc)
 static inline void ip_vs_lblc_full_check(struct ip_vs_service *svc)
 {
 	struct ip_vs_lblc_table *tbl = svc->sched_data;
-	struct ip_vs_lblc_entry *en, *nxt;
+	struct ip_vs_lblc_entry *en;
+	struct hlist_node *next;
 	unsigned long now = jiffies;
 	int i, j;
 
 	for (i=0, j=tbl->rover; i<IP_VS_LBLC_TAB_SIZE; i++) {
 		j = (j + 1) & IP_VS_LBLC_TAB_MASK;
 
-		write_lock(&svc->sched_lock);
-		list_for_each_entry_safe(en, nxt, &tbl->bucket[j], list) {
+		spin_lock(&svc->sched_lock);
+		hlist_for_each_entry_safe(en, next, &tbl->bucket[j], list) {
 			if (time_before(now,
 					en->lastuse +
 					sysctl_lblc_expiration(svc)))
@@ -269,7 +284,7 @@ static inline void ip_vs_lblc_full_check(struct ip_vs_service *svc)
 			ip_vs_lblc_free(en);
 			atomic_dec(&tbl->entries);
 		}
-		write_unlock(&svc->sched_lock);
+		spin_unlock(&svc->sched_lock);
 	}
 	tbl->rover = j;
 }
@@ -293,7 +308,8 @@ static void ip_vs_lblc_check_expire(unsigned long data)
 	unsigned long now = jiffies;
 	int goal;
 	int i, j;
-	struct ip_vs_lblc_entry *en, *nxt;
+	struct ip_vs_lblc_entry *en;
+	struct hlist_node *next;
 
 	if ((tbl->counter % COUNT_FOR_FULL_EXPIRATION) == 0) {
 		/* do full expiration check */
@@ -314,8 +330,8 @@ static void ip_vs_lblc_check_expire(unsigned long data)
 	for (i=0, j=tbl->rover; i<IP_VS_LBLC_TAB_SIZE; i++) {
 		j = (j + 1) & IP_VS_LBLC_TAB_MASK;
 
-		write_lock(&svc->sched_lock);
-		list_for_each_entry_safe(en, nxt, &tbl->bucket[j], list) {
+		spin_lock(&svc->sched_lock);
+		hlist_for_each_entry_safe(en, next, &tbl->bucket[j], list) {
 			if (time_before(now, en->lastuse + ENTRY_TIMEOUT))
 				continue;
 
@@ -323,7 +339,7 @@ static void ip_vs_lblc_check_expire(unsigned long data)
 			atomic_dec(&tbl->entries);
 			goal--;
 		}
-		write_unlock(&svc->sched_lock);
+		spin_unlock(&svc->sched_lock);
 		if (goal <= 0)
 			break;
 	}
@@ -354,11 +370,12 @@ static int ip_vs_lblc_init_svc(struct ip_vs_service *svc)
 	 *    Initialize the hash buckets
 	 */
 	for (i=0; i<IP_VS_LBLC_TAB_SIZE; i++) {
-		INIT_LIST_HEAD(&tbl->bucket[i]);
+		INIT_HLIST_HEAD(&tbl->bucket[i]);
 	}
 	tbl->max_size = IP_VS_LBLC_TAB_SIZE*16;
 	tbl->rover = 0;
 	tbl->counter = 1;
+	tbl->dead = 0;
 
 	/*
 	 *    Hook periodic timer for garbage collection
@@ -371,7 +388,7 @@ static int ip_vs_lblc_init_svc(struct ip_vs_service *svc)
 }
 
 
-static int ip_vs_lblc_done_svc(struct ip_vs_service *svc)
+static void ip_vs_lblc_done_svc(struct ip_vs_service *svc)
 {
 	struct ip_vs_lblc_table *tbl = svc->sched_data;
 
@@ -379,14 +396,12 @@ static int ip_vs_lblc_done_svc(struct ip_vs_service *svc)
 	del_timer_sync(&tbl->periodic_timer);
 
 	/* got to clean up table entries here */
-	ip_vs_lblc_flush(tbl);
+	ip_vs_lblc_flush(svc);
 
 	/* release the table itself */
-	kfree(tbl);
+	kfree_rcu(tbl, rcu_head);
 	IP_VS_DBG(6, "LBLC hash table (memory=%Zdbytes) released\n",
 		  sizeof(*tbl));
-
-	return 0;
 }
 
 
@@ -408,7 +423,7 @@ __ip_vs_lblc_schedule(struct ip_vs_service *svc)
 	 * The server with weight=0 is quiesced and will not receive any
 	 * new connection.
 	 */
-	list_for_each_entry(dest, &svc->destinations, n_list) {
+	list_for_each_entry_rcu(dest, &svc->destinations, n_list) {
 		if (dest->flags & IP_VS_DEST_F_OVERLOAD)
 			continue;
 		if (atomic_read(&dest->weight) > 0) {
@@ -423,7 +438,7 @@ __ip_vs_lblc_schedule(struct ip_vs_service *svc)
 	 *    Find the destination with the least load.
 	 */
   nextstage:
-	list_for_each_entry_continue(dest, &svc->destinations, n_list) {
+	list_for_each_entry_continue_rcu(dest, &svc->destinations, n_list) {
 		if (dest->flags & IP_VS_DEST_F_OVERLOAD)
 			continue;
 
@@ -457,7 +472,7 @@ is_overloaded(struct ip_vs_dest *dest, struct ip_vs_service *svc)
 	if (atomic_read(&dest->activeconns) > atomic_read(&dest->weight)) {
 		struct ip_vs_dest *d;
 
-		list_for_each_entry(d, &svc->destinations, n_list) {
+		list_for_each_entry_rcu(d, &svc->destinations, n_list) {
 			if (atomic_read(&d->activeconns)*2
 			    < atomic_read(&d->weight)) {
 				return 1;
@@ -484,7 +499,6 @@ ip_vs_lblc_schedule(struct ip_vs_service *svc, const struct sk_buff *skb)
 	IP_VS_DBG(6, "%s(): Scheduling...\n", __func__);
 
 	/* First look in our cache */
-	read_lock(&svc->sched_lock);
 	en = ip_vs_lblc_get(svc->af, tbl, &iph.daddr);
 	if (en) {
 		/* We only hold a read lock, but this is atomic */
@@ -499,14 +513,11 @@ ip_vs_lblc_schedule(struct ip_vs_service *svc, const struct sk_buff *skb)
 		 * free up entries from the trash at any time.
 		 */
 
-		if (en->dest->flags & IP_VS_DEST_F_AVAILABLE)
-			dest = en->dest;
+		dest = rcu_dereference(en->dest);
+		if ((dest->flags & IP_VS_DEST_F_AVAILABLE) &&
+		    atomic_read(&dest->weight) > 0 && !is_overloaded(dest, svc))
+			goto out;
 	}
-	read_unlock(&svc->sched_lock);
-
-	/* If the destination has a weight and is not overloaded, use it */
-	if (dest && atomic_read(&dest->weight) > 0 && !is_overloaded(dest, svc))
-		goto out;
 
 	/* No cache entry or it is invalid, time to schedule */
 	dest = __ip_vs_lblc_schedule(svc);
@@ -516,9 +527,10 @@ ip_vs_lblc_schedule(struct ip_vs_service *svc, const struct sk_buff *skb)
 	}
 
 	/* If we fail to create a cache entry, we'll just use the valid dest */
-	write_lock(&svc->sched_lock);
-	ip_vs_lblc_new(tbl, &iph.daddr, dest);
-	write_unlock(&svc->sched_lock);
+	spin_lock_bh(&svc->sched_lock);
+	if (!tbl->dead)
+		ip_vs_lblc_new(tbl, &iph.daddr, dest);
+	spin_unlock_bh(&svc->sched_lock);
 
 out:
 	IP_VS_DBG_BUF(6, "LBLC: destination IP address %s --> server %s:%d\n",
@@ -621,6 +633,7 @@ static void __exit ip_vs_lblc_cleanup(void)
 {
 	unregister_ip_vs_scheduler(&ip_vs_lblc_scheduler);
 	unregister_pernet_subsys(&ip_vs_lblc_ops);
+	synchronize_rcu();
 }