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

Pull networking updates from David Miller:

 1) Add VF IPSEC offload support in ixgbe, from Shannon Nelson.

 2) Add zero-copy AF_XDP support to i40e, from Björn Töpel.

 3) All in-tree drivers are converted to {g,s}et_link_ksettings() so we
    can get rid of the {g,s}et_settings ethtool callbacks, from Michal
    Kubecek.

 4) Add software timestamping to veth driver, from Michael Walle.

 5) More work to make packet classifiers and actions lockless, from Vlad
    Buslov.

 6) Support sticky FDB entries in bridge, from Nikolay Aleksandrov.

 7) Add ipv6 version of IP_MULTICAST_ALL sockopt, from Andre Naujoks.

 8) Support batching of XDP buffers in vhost_net, from Jason Wang.

 9) Add flow dissector BPF hook, from Petar Penkov.

10) i40e vf --> generic iavf conversion, from Jesse Brandeburg.

11) Add NLA_REJECT netlink attribute policy type, to signal when users
    provide attributes in situations which don't make sense. From
    Johannes Berg.

12) Switch TCP and fair-queue scheduler over to earliest departure time
    model. From Eric Dumazet.

13) Improve guest receive performance by doing rx busy polling in tx
    path of vhost networking driver, from Tonghao Zhang.

14) Add per-cgroup local storage to bpf

15) Add reference tracking to BPF, from Joe Stringer. The verifier can
    now make sure that references taken to objects are properly released
    by the program.

16) Support in-place encryption in TLS, from Vakul Garg.

17) Add new taprio packet scheduler, from Vinicius Costa Gomes.

18) Lots of selftests additions, too numerous to mention one by one here
    but all of which are very much appreciated.

19) Support offloading of eBPF programs containing BPF to BPF calls in
    nfp driver, frm Quentin Monnet.

20) Move dpaa2_ptp driver out of staging, from Yangbo Lu.

21) Lots of u32 classifier cleanups and simplifications, from Al Viro.

22) Add new strict versions of netlink message parsers, and enable them
    for some situations. From David Ahern.

23) Evict neighbour entries on carrier down, also from David Ahern.

24) Support BPF sk_msg verdict programs with kTLS, from Daniel Borkmann
    and John Fastabend.

25) Add support for filtering route dumps, from David Ahern.

26) New igc Intel driver for 2.5G parts, from Sasha Neftin et al.

27) Allow vxlan enslavement to bridges in mlxsw driver, from Ido
    Schimmel.

28) Add queue and stack map types to eBPF, from Mauricio Vasquez B.

29) Add back byte-queue-limit support to r8169, with all the bug fixes
    in other areas of the driver it works now! From Florian Westphal and
    Heiner Kallweit.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2147 commits)
  tcp: add tcp_reset_xmit_timer() helper
  qed: Fix static checker warning
  Revert "be2net: remove desc field from be_eq_obj"
  Revert "net: simplify sock_poll_wait"
  net: socionext: Reset tx queue in ndo_stop
  net: socionext: Add dummy PHY register read in phy_write()
  net: socionext: Stop PHY before resetting netsec
  net: stmmac: Set OWN bit for jumbo frames
  arm64: dts: stratix10: Support Ethernet Jumbo frame
  tls: Add maintainers
  net: ethernet: ti: cpsw: unsync mcast entries while switch promisc mode
  octeontx2-af: Support for NIXLF's UCAST/PROMISC/ALLMULTI modes
  octeontx2-af: Support for setting MAC address
  octeontx2-af: Support for changing RSS algorithm
  octeontx2-af: NIX Rx flowkey configuration for RSS
  octeontx2-af: Install ucast and bcast pkt forwarding rules
  octeontx2-af: Add LMAC channel info to NIXLF_ALLOC response
  octeontx2-af: NPC MCAM and LDATA extract minimal configuration
  octeontx2-af: Enable packet length and csum validation
  octeontx2-af: Support for VTAG strip and capture
  ...

1 files changed, 179 insertions, 70 deletions

diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 70f144ac5e1d..f427a1e00e7e 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -242,8 +242,8 @@ static void tcf_chain_destroy(struct tcf_chain *chain)
 	if (!chain->index)
 		block->chain0.chain = NULL;
 	kfree(chain);
-	if (list_empty(&block->chain_list) && block->refcnt == 0)
-		kfree(block);
+	if (list_empty(&block->chain_list) && !refcount_read(&block->refcnt))
+		kfree_rcu(block, rcu);
 }
 
 static void tcf_chain_hold(struct tcf_chain *chain)
@@ -475,6 +475,7 @@ tcf_chain0_head_change_cb_del(struct tcf_block *block,
 }
 
 struct tcf_net {
+	spinlock_t idr_lock; /* Protects idr */
 	struct idr idr;
 };
 
@@ -484,16 +485,25 @@ static int tcf_block_insert(struct tcf_block *block, struct net *net,
 			    struct netlink_ext_ack *extack)
 {
 	struct tcf_net *tn = net_generic(net, tcf_net_id);
+	int err;
+
+	idr_preload(GFP_KERNEL);
+	spin_lock(&tn->idr_lock);
+	err = idr_alloc_u32(&tn->idr, block, &block->index, block->index,
+			    GFP_NOWAIT);
+	spin_unlock(&tn->idr_lock);
+	idr_preload_end();
 
-	return idr_alloc_u32(&tn->idr, block, &block->index, block->index,
-			     GFP_KERNEL);
+	return err;
 }
 
 static void tcf_block_remove(struct tcf_block *block, struct net *net)
 {
 	struct tcf_net *tn = net_generic(net, tcf_net_id);
 
+	spin_lock(&tn->idr_lock);
 	idr_remove(&tn->idr, block->index);
+	spin_unlock(&tn->idr_lock);
 }
 
 static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q,
@@ -512,7 +522,7 @@ static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q,
 	INIT_LIST_HEAD(&block->owner_list);
 	INIT_LIST_HEAD(&block->chain0.filter_chain_list);
 
-	block->refcnt = 1;
+	refcount_set(&block->refcnt, 1);
 	block->net = net;
 	block->index = block_index;
 
@@ -529,6 +539,78 @@ static struct tcf_block *tcf_block_lookup(struct net *net, u32 block_index)
 	return idr_find(&tn->idr, block_index);
 }
 
+static struct tcf_block *tcf_block_refcnt_get(struct net *net, u32 block_index)
+{
+	struct tcf_block *block;
+
+	rcu_read_lock();
+	block = tcf_block_lookup(net, block_index);
+	if (block && !refcount_inc_not_zero(&block->refcnt))
+		block = NULL;
+	rcu_read_unlock();
+
+	return block;
+}
+
+static void tcf_block_flush_all_chains(struct tcf_block *block)
+{
+	struct tcf_chain *chain;
+
+	/* Hold a refcnt for all chains, so that they don't disappear
+	 * while we are iterating.
+	 */
+	list_for_each_entry(chain, &block->chain_list, list)
+		tcf_chain_hold(chain);
+
+	list_for_each_entry(chain, &block->chain_list, list)
+		tcf_chain_flush(chain);
+}
+
+static void tcf_block_put_all_chains(struct tcf_block *block)
+{
+	struct tcf_chain *chain, *tmp;
+
+	/* At this point, all the chains should have refcnt >= 1. */
+	list_for_each_entry_safe(chain, tmp, &block->chain_list, list) {
+		tcf_chain_put_explicitly_created(chain);
+		tcf_chain_put(chain);
+	}
+}
+
+static void __tcf_block_put(struct tcf_block *block, struct Qdisc *q,
+			    struct tcf_block_ext_info *ei)
+{
+	if (refcount_dec_and_test(&block->refcnt)) {
+		/* Flushing/putting all chains will cause the block to be
+		 * deallocated when last chain is freed. However, if chain_list
+		 * is empty, block has to be manually deallocated. After block
+		 * reference counter reached 0, it is no longer possible to
+		 * increment it or add new chains to block.
+		 */
+		bool free_block = list_empty(&block->chain_list);
+
+		if (tcf_block_shared(block))
+			tcf_block_remove(block, block->net);
+		if (!free_block)
+			tcf_block_flush_all_chains(block);
+
+		if (q)
+			tcf_block_offload_unbind(block, q, ei);
+
+		if (free_block)
+			kfree_rcu(block, rcu);
+		else
+			tcf_block_put_all_chains(block);
+	} else if (q) {
+		tcf_block_offload_unbind(block, q, ei);
+	}
+}
+
+static void tcf_block_refcnt_put(struct tcf_block *block)
+{
+	__tcf_block_put(block, NULL, NULL);
+}
+
 /* Find tcf block.
  * Set q, parent, cl when appropriate.
  */
@@ -539,9 +621,10 @@ static struct tcf_block *tcf_block_find(struct net *net, struct Qdisc **q,
 					struct netlink_ext_ack *extack)
 {
 	struct tcf_block *block;
+	int err = 0;
 
 	if (ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
-		block = tcf_block_lookup(net, block_index);
+		block = tcf_block_refcnt_get(net, block_index);
 		if (!block) {
 			NL_SET_ERR_MSG(extack, "Block of given index was not found");
 			return ERR_PTR(-EINVAL);
@@ -550,55 +633,106 @@ static struct tcf_block *tcf_block_find(struct net *net, struct Qdisc **q,
 		const struct Qdisc_class_ops *cops;
 		struct net_device *dev;
 
+		rcu_read_lock();
+
 		/* Find link */
-		dev = __dev_get_by_index(net, ifindex);
-		if (!dev)
+		dev = dev_get_by_index_rcu(net, ifindex);
+		if (!dev) {
+			rcu_read_unlock();
 			return ERR_PTR(-ENODEV);
+		}
 
 		/* Find qdisc */
 		if (!*parent) {
 			*q = dev->qdisc;
 			*parent = (*q)->handle;
 		} else {
-			*q = qdisc_lookup(dev, TC_H_MAJ(*parent));
+			*q = qdisc_lookup_rcu(dev, TC_H_MAJ(*parent));
 			if (!*q) {
 				NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
-				return ERR_PTR(-EINVAL);
+				err = -EINVAL;
+				goto errout_rcu;
 			}
 		}
 
+		*q = qdisc_refcount_inc_nz(*q);
+		if (!*q) {
+			NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
+			err = -EINVAL;
+			goto errout_rcu;
+		}
+
 		/* Is it classful? */
 		cops = (*q)->ops->cl_ops;
 		if (!cops) {
 			NL_SET_ERR_MSG(extack, "Qdisc not classful");
-			return ERR_PTR(-EINVAL);
+			err = -EINVAL;
+			goto errout_rcu;
 		}
 
 		if (!cops->tcf_block) {
 			NL_SET_ERR_MSG(extack, "Class doesn't support blocks");
-			return ERR_PTR(-EOPNOTSUPP);
+			err = -EOPNOTSUPP;
+			goto errout_rcu;
 		}
 
+		/* At this point we know that qdisc is not noop_qdisc,
+		 * which means that qdisc holds a reference to net_device
+		 * and we hold a reference to qdisc, so it is safe to release
+		 * rcu read lock.
+		 */
+		rcu_read_unlock();
+
 		/* Do we search for filter, attached to class? */
 		if (TC_H_MIN(*parent)) {
 			*cl = cops->find(*q, *parent);
 			if (*cl == 0) {
 				NL_SET_ERR_MSG(extack, "Specified class doesn't exist");
-				return ERR_PTR(-ENOENT);
+				err = -ENOENT;
+				goto errout_qdisc;
 			}
 		}
 
 		/* And the last stroke */
 		block = cops->tcf_block(*q, *cl, extack);
-		if (!block)
-			return ERR_PTR(-EINVAL);
+		if (!block) {
+			err = -EINVAL;
+			goto errout_qdisc;
+		}
 		if (tcf_block_shared(block)) {
 			NL_SET_ERR_MSG(extack, "This filter block is shared. Please use the block index to manipulate the filters");
-			return ERR_PTR(-EOPNOTSUPP);
+			err = -EOPNOTSUPP;
+			goto errout_qdisc;
 		}
+
+		/* Always take reference to block in order to support execution
+		 * of rules update path of cls API without rtnl lock. Caller
+		 * must release block when it is finished using it. 'if' block
+		 * of this conditional obtain reference to block by calling
+		 * tcf_block_refcnt_get().
+		 */
+		refcount_inc(&block->refcnt);
 	}
 
 	return block;
+
+errout_rcu:
+	rcu_read_unlock();
+errout_qdisc:
+	if (*q) {
+		qdisc_put(*q);
+		*q = NULL;
+	}
+	return ERR_PTR(err);
+}
+
+static void tcf_block_release(struct Qdisc *q, struct tcf_block *block)
+{
+	if (!IS_ERR_OR_NULL(block))
+		tcf_block_refcnt_put(block);
+
+	if (q)
+		qdisc_put(q);
 }
 
 struct tcf_block_owner_item {
@@ -666,21 +800,16 @@ int tcf_block_get_ext(struct tcf_block **p_block, struct Qdisc *q,
 {
 	struct net *net = qdisc_net(q);
 	struct tcf_block *block = NULL;
-	bool created = false;
 	int err;
 
-	if (ei->block_index) {
+	if (ei->block_index)
 		/* block_index not 0 means the shared block is requested */
-		block = tcf_block_lookup(net, ei->block_index);
-		if (block)
-			block->refcnt++;
-	}
+		block = tcf_block_refcnt_get(net, ei->block_index);
 
 	if (!block) {
 		block = tcf_block_create(net, q, ei->block_index, extack);
 		if (IS_ERR(block))
 			return PTR_ERR(block);
-		created = true;
 		if (tcf_block_shared(block)) {
 			err = tcf_block_insert(block, net, extack);
 			if (err)
@@ -710,14 +839,8 @@ err_block_offload_bind:
 err_chain0_head_change_cb_add:
 	tcf_block_owner_del(block, q, ei->binder_type);
 err_block_owner_add:
-	if (created) {
-		if (tcf_block_shared(block))
-			tcf_block_remove(block, net);
 err_block_insert:
-		kfree(block);
-	} else {
-		block->refcnt--;
-	}
+	tcf_block_refcnt_put(block);
 	return err;
 }
 EXPORT_SYMBOL(tcf_block_get_ext);
@@ -749,42 +872,12 @@ EXPORT_SYMBOL(tcf_block_get);
 void tcf_block_put_ext(struct tcf_block *block, struct Qdisc *q,
 		       struct tcf_block_ext_info *ei)
 {
-	struct tcf_chain *chain, *tmp;
-
 	if (!block)
 		return;
 	tcf_chain0_head_change_cb_del(block, ei);
 	tcf_block_owner_del(block, q, ei->binder_type);
 
-	if (block->refcnt == 1) {
-		if (tcf_block_shared(block))
-			tcf_block_remove(block, block->net);
-
-		/* Hold a refcnt for all chains, so that they don't disappear
-		 * while we are iterating.
-		 */
-		list_for_each_entry(chain, &block->chain_list, list)
-			tcf_chain_hold(chain);
-
-		list_for_each_entry(chain, &block->chain_list, list)
-			tcf_chain_flush(chain);
-	}
-
-	tcf_block_offload_unbind(block, q, ei);
-
-	if (block->refcnt == 1) {
-		/* At this point, all the chains should have refcnt >= 1. */
-		list_for_each_entry_safe(chain, tmp, &block->chain_list, list) {
-			tcf_chain_put_explicitly_created(chain);
-			tcf_chain_put(chain);
-		}
-
-		block->refcnt--;
-		if (list_empty(&block->chain_list))
-			kfree(block);
-	} else {
-		block->refcnt--;
-	}
+	__tcf_block_put(block, q, ei);
 }
 EXPORT_SYMBOL(tcf_block_put_ext);
 
@@ -1334,6 +1427,7 @@ replay:
 errout:
 	if (chain)
 		tcf_chain_put(chain);
+	tcf_block_release(q, block);
 	if (err == -EAGAIN)
 		/* Replay the request. */
 		goto replay;
@@ -1455,6 +1549,7 @@ static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
 errout:
 	if (chain)
 		tcf_chain_put(chain);
+	tcf_block_release(q, block);
 	return err;
 }
 
@@ -1540,6 +1635,7 @@ static int tc_get_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
 errout:
 	if (chain)
 		tcf_chain_put(chain);
+	tcf_block_release(q, block);
 	return err;
 }
 
@@ -1633,12 +1729,13 @@ static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
 	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
 		return skb->len;
 
-	err = nlmsg_parse(cb->nlh, sizeof(*tcm), tca, TCA_MAX, NULL, NULL);
+	err = nlmsg_parse(cb->nlh, sizeof(*tcm), tca, TCA_MAX, NULL,
+			  cb->extack);
 	if (err)
 		return err;
 
 	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
-		block = tcf_block_lookup(net, tcm->tcm_block_index);
+		block = tcf_block_refcnt_get(net, tcm->tcm_block_index);
 		if (!block)
 			goto out;
 		/* If we work with block index, q is NULL and parent value
@@ -1697,6 +1794,8 @@ static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
 		}
 	}
 
+	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK)
+		tcf_block_refcnt_put(block);
 	cb->args[0] = index;
 
 out:
@@ -1856,7 +1955,8 @@ replay:
 	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
 	if (chain_index > TC_ACT_EXT_VAL_MASK) {
 		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
-		return -EINVAL;
+		err = -EINVAL;
+		goto errout_block;
 	}
 	chain = tcf_chain_lookup(block, chain_index);
 	if (n->nlmsg_type == RTM_NEWCHAIN) {
@@ -1868,23 +1968,27 @@ replay:
 				tcf_chain_hold(chain);
 			} else {
 				NL_SET_ERR_MSG(extack, "Filter chain already exists");
-				return -EEXIST;
+				err = -EEXIST;
+				goto errout_block;
 			}
 		} else {
 			if (!(n->nlmsg_flags & NLM_F_CREATE)) {
 				NL_SET_ERR_MSG(extack, "Need both RTM_NEWCHAIN and NLM_F_CREATE to create a new chain");
-				return -ENOENT;
+				err = -ENOENT;
+				goto errout_block;
 			}
 			chain = tcf_chain_create(block, chain_index);
 			if (!chain) {
 				NL_SET_ERR_MSG(extack, "Failed to create filter chain");
-				return -ENOMEM;
+				err = -ENOMEM;
+				goto errout_block;
 			}
 		}
 	} else {
 		if (!chain || tcf_chain_held_by_acts_only(chain)) {
 			NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
-			return -EINVAL;
+			err = -EINVAL;
+			goto errout_block;
 		}
 		tcf_chain_hold(chain);
 	}
@@ -1928,6 +2032,8 @@ replay:
 
 errout:
 	tcf_chain_put(chain);
+errout_block:
+	tcf_block_release(q, block);
 	if (err == -EAGAIN)
 		/* Replay the request. */
 		goto replay;
@@ -1952,12 +2058,12 @@ static int tc_dump_chain(struct sk_buff *skb, struct netlink_callback *cb)
 		return skb->len;
 
 	err = nlmsg_parse(cb->nlh, sizeof(*tcm), tca, TCA_MAX, rtm_tca_policy,
-			  NULL);
+			  cb->extack);
 	if (err)
 		return err;
 
 	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
-		block = tcf_block_lookup(net, tcm->tcm_block_index);
+		block = tcf_block_refcnt_get(net, tcm->tcm_block_index);
 		if (!block)
 			goto out;
 		/* If we work with block index, q is NULL and parent value
@@ -2024,6 +2130,8 @@ static int tc_dump_chain(struct sk_buff *skb, struct netlink_callback *cb)
 		index++;
 	}
 
+	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK)
+		tcf_block_refcnt_put(block);
 	cb->args[0] = index;
 
 out:
@@ -2216,6 +2324,7 @@ static __net_init int tcf_net_init(struct net *net)
 {
 	struct tcf_net *tn = net_generic(net, tcf_net_id);
 
+	spin_lock_init(&tn->idr_lock);
 	idr_init(&tn->idr);
 	return 0;
 }