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

Pull networking updates from David Miller:
 "Most notable changes in here:

   1) By far the biggest accomplishment, thanks to a large range of
      contributors, is the addition of multi-send for transmit.  This is
      the result of discussions back in Chicago, and the hard work of
      several individuals.

      Now, when the ->ndo_start_xmit() method of a driver sees
      skb->xmit_more as true, it can choose to defer the doorbell
      telling the driver to start processing the new TX queue entires.

      skb->xmit_more means that the generic networking is guaranteed to
      call the driver immediately with another SKB to send.

      There is logic added to the qdisc layer to dequeue multiple
      packets at a time, and the handling mis-predicted offloads in
      software is now done with no locks held.

      Finally, pktgen is extended to have a "burst" parameter that can
      be used to test a multi-send implementation.

      Several drivers have xmit_more support: i40e, igb, ixgbe, mlx4,
      virtio_net

      Adding support is almost trivial, so export more drivers to
      support this optimization soon.

      I want to thank, in no particular or implied order, Jesper
      Dangaard Brouer, Eric Dumazet, Alexander Duyck, Tom Herbert, Jamal
      Hadi Salim, John Fastabend, Florian Westphal, Daniel Borkmann,
      David Tat, Hannes Frederic Sowa, and Rusty Russell.

   2) PTP and timestamping support in bnx2x, from Michal Kalderon.

   3) Allow adjusting the rx_copybreak threshold for a driver via
      ethtool, and add rx_copybreak support to enic driver.  From
      Govindarajulu Varadarajan.

   4) Significant enhancements to the generic PHY layer and the bcm7xxx
      driver in particular (EEE support, auto power down, etc.) from
      Florian Fainelli.

   5) Allow raw buffers to be used for flow dissection, allowing drivers
      to determine the optimal "linear pull" size for devices that DMA
      into pools of pages.  The objective is to get exactly the
      necessary amount of headers into the linear SKB area pre-pulled,
      but no more.  The new interface drivers use is eth_get_headlen().
      From WANG Cong, with driver conversions (several had their own
      by-hand duplicated implementations) by Alexander Duyck and Eric
      Dumazet.

   6) Support checksumming more smoothly and efficiently for
      encapsulations, and add "foo over UDP" facility.  From Tom
      Herbert.

   7) Add Broadcom SF2 switch driver to DSA layer, from Florian
      Fainelli.

   8) eBPF now can load programs via a system call and has an extensive
      testsuite.  Alexei Starovoitov and Daniel Borkmann.

   9) Major overhaul of the packet scheduler to use RCU in several major
      areas such as the classifiers and rate estimators.  From John
      Fastabend.

  10) Add driver for Intel FM10000 Ethernet Switch, from Alexander
      Duyck.

  11) Rearrange TCP_SKB_CB() to reduce cache line misses, from Eric
      Dumazet.

  12) Add Datacenter TCP congestion control algorithm support, From
      Florian Westphal.

  13) Reorganize sk_buff so that __copy_skb_header() is significantly
      faster.  From Eric Dumazet"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1558 commits)
  netlabel: directly return netlbl_unlabel_genl_init()
  net: add netdev_txq_bql_{enqueue, complete}_prefetchw() helpers
  net: description of dma_cookie cause make xmldocs warning
  cxgb4: clean up a type issue
  cxgb4: potential shift wrapping bug
  i40e: skb->xmit_more support
  net: fs_enet: Add NAPI TX
  net: fs_enet: Remove non NAPI RX
  r8169:add support for RTL8168EP
  net_sched: copy exts->type in tcf_exts_change()
  wimax: convert printk to pr_foo()
  af_unix: remove 0 assignment on static
  ipv6: Do not warn for informational ICMP messages, regardless of type.
  Update Intel Ethernet Driver maintainers list
  bridge: Save frag_max_size between PRE_ROUTING and POST_ROUTING
  tipc: fix bug in multicast congestion handling
  net: better IFF_XMIT_DST_RELEASE support
  net/mlx4_en: remove NETDEV_TX_BUSY
  3c59x: fix bad split of cpu_to_le32(pci_map_single())
  net: bcmgenet: fix Tx ring priority programming
  ...

1 files changed, 169 insertions, 104 deletions

diff --git a/net/sched/cls_tcindex.c b/net/sched/cls_tcindex.c
index 3e9f76413b3b..30f10fb07f4a 100644
--- a/net/sched/cls_tcindex.c
+++ b/net/sched/cls_tcindex.c
@@ -32,19 +32,21 @@ struct tcindex_filter_result {
 struct tcindex_filter {
 	u16 key;
 	struct tcindex_filter_result result;
-	struct tcindex_filter *next;
+	struct tcindex_filter __rcu *next;
+	struct rcu_head rcu;
 };
 
 
 struct tcindex_data {
 	struct tcindex_filter_result *perfect; /* perfect hash; NULL if none */
-	struct tcindex_filter **h; /* imperfect hash; only used if !perfect;
-				      NULL if unused */
+	struct tcindex_filter __rcu **h; /* imperfect hash; */
+	struct tcf_proto *tp;
 	u16 mask;		/* AND key with mask */
-	int shift;		/* shift ANDed key to the right */
-	int hash;		/* hash table size; 0 if undefined */
-	int alloc_hash;		/* allocated size */
-	int fall_through;	/* 0: only classify if explicit match */
+	u32 shift;		/* shift ANDed key to the right */
+	u32 hash;		/* hash table size; 0 if undefined */
+	u32 alloc_hash;		/* allocated size */
+	u32 fall_through;	/* 0: only classify if explicit match */
+	struct rcu_head rcu;
 };
 
 static inline int
@@ -56,13 +58,18 @@ tcindex_filter_is_set(struct tcindex_filter_result *r)
 static struct tcindex_filter_result *
 tcindex_lookup(struct tcindex_data *p, u16 key)
 {
-	struct tcindex_filter *f;
+	if (p->perfect) {
+		struct tcindex_filter_result *f = p->perfect + key;
+
+		return tcindex_filter_is_set(f) ? f : NULL;
+	} else if (p->h) {
+		struct tcindex_filter __rcu **fp;
+		struct tcindex_filter *f;
 
-	if (p->perfect)
-		return tcindex_filter_is_set(p->perfect + key) ?
-			p->perfect + key : NULL;
-	else if (p->h) {
-		for (f = p->h[key % p->hash]; f; f = f->next)
+		fp = &p->h[key % p->hash];
+		for (f = rcu_dereference_bh_rtnl(*fp);
+		     f;
+		     fp = &f->next, f = rcu_dereference_bh_rtnl(*fp))
 			if (f->key == key)
 				return &f->result;
 	}
@@ -74,7 +81,7 @@ tcindex_lookup(struct tcindex_data *p, u16 key)
 static int tcindex_classify(struct sk_buff *skb, const struct tcf_proto *tp,
 			    struct tcf_result *res)
 {
-	struct tcindex_data *p = tp->root;
+	struct tcindex_data *p = rcu_dereference_bh(tp->root);
 	struct tcindex_filter_result *f;
 	int key = (skb->tc_index & p->mask) >> p->shift;
 
@@ -99,7 +106,7 @@ static int tcindex_classify(struct sk_buff *skb, const struct tcf_proto *tp,
 
 static unsigned long tcindex_get(struct tcf_proto *tp, u32 handle)
 {
-	struct tcindex_data *p = tp->root;
+	struct tcindex_data *p = rtnl_dereference(tp->root);
 	struct tcindex_filter_result *r;
 
 	pr_debug("tcindex_get(tp %p,handle 0x%08x)\n", tp, handle);
@@ -129,49 +136,59 @@ static int tcindex_init(struct tcf_proto *tp)
 	p->hash = DEFAULT_HASH_SIZE;
 	p->fall_through = 1;
 
-	tp->root = p;
+	rcu_assign_pointer(tp->root, p);
 	return 0;
 }
 
-
 static int
-__tcindex_delete(struct tcf_proto *tp, unsigned long arg, int lock)
+tcindex_delete(struct tcf_proto *tp, unsigned long arg)
 {
-	struct tcindex_data *p = tp->root;
+	struct tcindex_data *p = rtnl_dereference(tp->root);
 	struct tcindex_filter_result *r = (struct tcindex_filter_result *) arg;
+	struct tcindex_filter __rcu **walk;
 	struct tcindex_filter *f = NULL;
 
-	pr_debug("tcindex_delete(tp %p,arg 0x%lx),p %p,f %p\n", tp, arg, p, f);
+	pr_debug("tcindex_delete(tp %p,arg 0x%lx),p %p\n", tp, arg, p);
 	if (p->perfect) {
 		if (!r->res.class)
 			return -ENOENT;
 	} else {
 		int i;
-		struct tcindex_filter **walk = NULL;
 
-		for (i = 0; i < p->hash; i++)
-			for (walk = p->h+i; *walk; walk = &(*walk)->next)
-				if (&(*walk)->result == r)
+		for (i = 0; i < p->hash; i++) {
+			walk = p->h + i;
+			for (f = rtnl_dereference(*walk); f;
+			     walk = &f->next, f = rtnl_dereference(*walk)) {
+				if (&f->result == r)
 					goto found;
+			}
+		}
 		return -ENOENT;
 
 found:
-		f = *walk;
-		if (lock)
-			tcf_tree_lock(tp);
-		*walk = f->next;
-		if (lock)
-			tcf_tree_unlock(tp);
+		rcu_assign_pointer(*walk, rtnl_dereference(f->next));
 	}
 	tcf_unbind_filter(tp, &r->res);
-	tcf_exts_destroy(tp, &r->exts);
-	kfree(f);
+	tcf_exts_destroy(&r->exts);
+	if (f)
+		kfree_rcu(f, rcu);
 	return 0;
 }
 
-static int tcindex_delete(struct tcf_proto *tp, unsigned long arg)
+static int tcindex_destroy_element(struct tcf_proto *tp,
+				   unsigned long arg,
+				   struct tcf_walker *walker)
 {
-	return __tcindex_delete(tp, arg, 1);
+	return tcindex_delete(tp, arg);
+}
+
+static void __tcindex_destroy(struct rcu_head *head)
+{
+	struct tcindex_data *p = container_of(head, struct tcindex_data, rcu);
+
+	kfree(p->perfect);
+	kfree(p->h);
+	kfree(p);
 }
 
 static inline int
@@ -194,6 +211,14 @@ static void tcindex_filter_result_init(struct tcindex_filter_result *r)
 	tcf_exts_init(&r->exts, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
 }
 
+static void __tcindex_partial_destroy(struct rcu_head *head)
+{
+	struct tcindex_data *p = container_of(head, struct tcindex_data, rcu);
+
+	kfree(p->perfect);
+	kfree(p);
+}
+
 static int
 tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
 		  u32 handle, struct tcindex_data *p,
@@ -203,7 +228,7 @@ tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
 	int err, balloc = 0;
 	struct tcindex_filter_result new_filter_result, *old_r = r;
 	struct tcindex_filter_result cr;
-	struct tcindex_data cp;
+	struct tcindex_data *cp, *oldp;
 	struct tcindex_filter *f = NULL; /* make gcc behave */
 	struct tcf_exts e;
 
@@ -212,89 +237,130 @@ tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
 	if (err < 0)
 		return err;
 
-	memcpy(&cp, p, sizeof(cp));
-	tcindex_filter_result_init(&new_filter_result);
+	err = -ENOMEM;
+	/* tcindex_data attributes must look atomic to classifier/lookup so
+	 * allocate new tcindex data and RCU assign it onto root. Keeping
+	 * perfect hash and hash pointers from old data.
+	 */
+	cp = kzalloc(sizeof(*cp), GFP_KERNEL);
+	if (!cp)
+		goto errout;
+
+	cp->mask = p->mask;
+	cp->shift = p->shift;
+	cp->hash = p->hash;
+	cp->alloc_hash = p->alloc_hash;
+	cp->fall_through = p->fall_through;
+	cp->tp = tp;
 
+	if (p->perfect) {
+		int i;
+
+		cp->perfect = kmemdup(p->perfect,
+				      sizeof(*r) * cp->hash, GFP_KERNEL);
+		if (!cp->perfect)
+			goto errout;
+		for (i = 0; i < cp->hash; i++)
+			tcf_exts_init(&cp->perfect[i].exts,
+				      TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
+		balloc = 1;
+	}
+	cp->h = p->h;
+
+	tcindex_filter_result_init(&new_filter_result);
 	tcindex_filter_result_init(&cr);
 	if (old_r)
 		cr.res = r->res;
 
 	if (tb[TCA_TCINDEX_HASH])
-		cp.hash = nla_get_u32(tb[TCA_TCINDEX_HASH]);
+		cp->hash = nla_get_u32(tb[TCA_TCINDEX_HASH]);
 
 	if (tb[TCA_TCINDEX_MASK])
-		cp.mask = nla_get_u16(tb[TCA_TCINDEX_MASK]);
+		cp->mask = nla_get_u16(tb[TCA_TCINDEX_MASK]);
 
 	if (tb[TCA_TCINDEX_SHIFT])
-		cp.shift = nla_get_u32(tb[TCA_TCINDEX_SHIFT]);
+		cp->shift = nla_get_u32(tb[TCA_TCINDEX_SHIFT]);
 
 	err = -EBUSY;
+
 	/* Hash already allocated, make sure that we still meet the
 	 * requirements for the allocated hash.
 	 */
-	if (cp.perfect) {
-		if (!valid_perfect_hash(&cp) ||
-		    cp.hash > cp.alloc_hash)
-			goto errout;
-	} else if (cp.h && cp.hash != cp.alloc_hash)
-		goto errout;
+	if (cp->perfect) {
+		if (!valid_perfect_hash(cp) ||
+		    cp->hash > cp->alloc_hash)
+			goto errout_alloc;
+	} else if (cp->h && cp->hash != cp->alloc_hash) {
+		goto errout_alloc;
+	}
 
 	err = -EINVAL;
 	if (tb[TCA_TCINDEX_FALL_THROUGH])
-		cp.fall_through = nla_get_u32(tb[TCA_TCINDEX_FALL_THROUGH]);
+		cp->fall_through = nla_get_u32(tb[TCA_TCINDEX_FALL_THROUGH]);
 
-	if (!cp.hash) {
+	if (!cp->hash) {
 		/* Hash not specified, use perfect hash if the upper limit
 		 * of the hashing index is below the threshold.
 		 */
-		if ((cp.mask >> cp.shift) < PERFECT_HASH_THRESHOLD)
-			cp.hash = (cp.mask >> cp.shift) + 1;
+		if ((cp->mask >> cp->shift) < PERFECT_HASH_THRESHOLD)
+			cp->hash = (cp->mask >> cp->shift) + 1;
 		else
-			cp.hash = DEFAULT_HASH_SIZE;
+			cp->hash = DEFAULT_HASH_SIZE;
 	}
 
-	if (!cp.perfect && !cp.h)
-		cp.alloc_hash = cp.hash;
+	if (!cp->perfect && !cp->h)
+		cp->alloc_hash = cp->hash;
 
 	/* Note: this could be as restrictive as if (handle & ~(mask >> shift))
 	 * but then, we'd fail handles that may become valid after some future
 	 * mask change. While this is extremely unlikely to ever matter,
 	 * the check below is safer (and also more backwards-compatible).
 	 */
-	if (cp.perfect || valid_perfect_hash(&cp))
-		if (handle >= cp.alloc_hash)
-			goto errout;
+	if (cp->perfect || valid_perfect_hash(cp))
+		if (handle >= cp->alloc_hash)
+			goto errout_alloc;
 
 
 	err = -ENOMEM;
-	if (!cp.perfect && !cp.h) {
-		if (valid_perfect_hash(&cp)) {
+	if (!cp->perfect && !cp->h) {
+		if (valid_perfect_hash(cp)) {
 			int i;
 
-			cp.perfect = kcalloc(cp.hash, sizeof(*r), GFP_KERNEL);
-			if (!cp.perfect)
-				goto errout;
-			for (i = 0; i < cp.hash; i++)
-				tcf_exts_init(&cp.perfect[i].exts, TCA_TCINDEX_ACT,
+			cp->perfect = kcalloc(cp->hash, sizeof(*r), GFP_KERNEL);
+			if (!cp->perfect)
+				goto errout_alloc;
+			for (i = 0; i < cp->hash; i++)
+				tcf_exts_init(&cp->perfect[i].exts,
+					      TCA_TCINDEX_ACT,
 					      TCA_TCINDEX_POLICE);
 			balloc = 1;
 		} else {
-			cp.h = kcalloc(cp.hash, sizeof(f), GFP_KERNEL);
-			if (!cp.h)
-				goto errout;
+			struct tcindex_filter __rcu **hash;
+
+			hash = kcalloc(cp->hash,
+				       sizeof(struct tcindex_filter *),
+				       GFP_KERNEL);
+
+			if (!hash)
+				goto errout_alloc;
+
+			cp->h = hash;
 			balloc = 2;
 		}
 	}
 
-	if (cp.perfect)
-		r = cp.perfect + handle;
+	if (cp->perfect)
+		r = cp->perfect + handle;
 	else
-		r = tcindex_lookup(&cp, handle) ? : &new_filter_result;
+		r = tcindex_lookup(cp, handle) ? : &new_filter_result;
 
 	if (r == &new_filter_result) {
 		f = kzalloc(sizeof(*f), GFP_KERNEL);
 		if (!f)
 			goto errout_alloc;
+		f->key = handle;
+		tcindex_filter_result_init(&f->result);
+		f->next = NULL;
 	}
 
 	if (tb[TCA_TCINDEX_CLASSID]) {
@@ -307,34 +373,40 @@ tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
 	else
 		tcf_exts_change(tp, &cr.exts, &e);
 
-	tcf_tree_lock(tp);
 	if (old_r && old_r != r)
 		tcindex_filter_result_init(old_r);
 
-	memcpy(p, &cp, sizeof(cp));
+	oldp = p;
 	r->res = cr.res;
+	rcu_assign_pointer(tp->root, cp);
 
 	if (r == &new_filter_result) {
-		struct tcindex_filter **fp;
+		struct tcindex_filter *nfp;
+		struct tcindex_filter __rcu **fp;
 
-		f->key = handle;
-		f->result = new_filter_result;
-		f->next = NULL;
-		for (fp = p->h+(handle % p->hash); *fp; fp = &(*fp)->next)
-			/* nothing */;
-		*fp = f;
+		tcf_exts_change(tp, &f->result.exts, &r->exts);
+
+		fp = cp->h + (handle % cp->hash);
+		for (nfp = rtnl_dereference(*fp);
+		     nfp;
+		     fp = &nfp->next, nfp = rtnl_dereference(*fp))
+				; /* nothing */
+
+		rcu_assign_pointer(*fp, f);
 	}
-	tcf_tree_unlock(tp);
 
+	if (oldp)
+		call_rcu(&oldp->rcu, __tcindex_partial_destroy);
 	return 0;
 
 errout_alloc:
 	if (balloc == 1)
-		kfree(cp.perfect);
+		kfree(cp->perfect);
 	else if (balloc == 2)
-		kfree(cp.h);
+		kfree(cp->h);
 errout:
-	tcf_exts_destroy(tp, &e);
+	kfree(cp);
+	tcf_exts_destroy(&e);
 	return err;
 }
 
@@ -345,7 +417,7 @@ tcindex_change(struct net *net, struct sk_buff *in_skb,
 {
 	struct nlattr *opt = tca[TCA_OPTIONS];
 	struct nlattr *tb[TCA_TCINDEX_MAX + 1];
-	struct tcindex_data *p = tp->root;
+	struct tcindex_data *p = rtnl_dereference(tp->root);
 	struct tcindex_filter_result *r = (struct tcindex_filter_result *) *arg;
 	int err;
 
@@ -364,10 +436,9 @@ tcindex_change(struct net *net, struct sk_buff *in_skb,
 				 tca[TCA_RATE], ovr);
 }
 
-
 static void tcindex_walk(struct tcf_proto *tp, struct tcf_walker *walker)
 {
-	struct tcindex_data *p = tp->root;
+	struct tcindex_data *p = rtnl_dereference(tp->root);
 	struct tcindex_filter *f, *next;
 	int i;
 
@@ -390,8 +461,8 @@ static void tcindex_walk(struct tcf_proto *tp, struct tcf_walker *walker)
 	if (!p->h)
 		return;
 	for (i = 0; i < p->hash; i++) {
-		for (f = p->h[i]; f; f = next) {
-			next = f->next;
+		for (f = rtnl_dereference(p->h[i]); f; f = next) {
+			next = rtnl_dereference(f->next);
 			if (walker->count >= walker->skip) {
 				if (walker->fn(tp, (unsigned long) &f->result,
 				    walker) < 0) {
@@ -404,17 +475,9 @@ static void tcindex_walk(struct tcf_proto *tp, struct tcf_walker *walker)
 	}
 }
 
-
-static int tcindex_destroy_element(struct tcf_proto *tp,
-    unsigned long arg, struct tcf_walker *walker)
-{
-	return __tcindex_delete(tp, arg, 0);
-}
-
-
 static void tcindex_destroy(struct tcf_proto *tp)
 {
-	struct tcindex_data *p = tp->root;
+	struct tcindex_data *p = rtnl_dereference(tp->root);
 	struct tcf_walker walker;
 
 	pr_debug("tcindex_destroy(tp %p),p %p\n", tp, p);
@@ -422,17 +485,16 @@ static void tcindex_destroy(struct tcf_proto *tp)
 	walker.skip = 0;
 	walker.fn = tcindex_destroy_element;
 	tcindex_walk(tp, &walker);
-	kfree(p->perfect);
-	kfree(p->h);
-	kfree(p);
-	tp->root = NULL;
+
+	RCU_INIT_POINTER(tp->root, NULL);
+	call_rcu(&p->rcu, __tcindex_destroy);
 }
 
 
 static int tcindex_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
     struct sk_buff *skb, struct tcmsg *t)
 {
-	struct tcindex_data *p = tp->root;
+	struct tcindex_data *p = rtnl_dereference(tp->root);
 	struct tcindex_filter_result *r = (struct tcindex_filter_result *) fh;
 	unsigned char *b = skb_tail_pointer(skb);
 	struct nlattr *nest;
@@ -455,15 +517,18 @@ static int tcindex_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
 		nla_nest_end(skb, nest);
 	} else {
 		if (p->perfect) {
-			t->tcm_handle = r-p->perfect;
+			t->tcm_handle = r - p->perfect;
 		} else {
 			struct tcindex_filter *f;
+			struct tcindex_filter __rcu **fp;
 			int i;
 
 			t->tcm_handle = 0;
 			for (i = 0; !t->tcm_handle && i < p->hash; i++) {
-				for (f = p->h[i]; !t->tcm_handle && f;
-				     f = f->next) {
+				fp = &p->h[i];
+				for (f = rtnl_dereference(*fp);
+				     !t->tcm_handle && f;
+				     fp = &f->next, f = rtnl_dereference(*fp)) {
 					if (&f->result == r)
 						t->tcm_handle = f->key;
 				}