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authorDavid S. Miller <davem@davemloft.net>2018-10-12 21:38:46 -0700
committerDavid S. Miller <davem@davemloft.net>2018-10-12 21:38:46 -0700
commitd864991b220b7c62e81d21209e1fd978fd67352c (patch)
treeb570a1ad6fc1b959c5bcda6ceca0b321319c01e0 /net/ipv4/fib_semantics.c
parentMerge branch 's390-qeth-next' (diff)
parentMerge tag 'armsoc-fixes-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc (diff)
downloadlinux-dev-d864991b220b7c62e81d21209e1fd978fd67352c.tar.xz
linux-dev-d864991b220b7c62e81d21209e1fd978fd67352c.zip
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts were easy to resolve using immediate context mostly, except the cls_u32.c one where I simply too the entire HEAD chunk. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/fib_semantics.c')
-rw-r--r--net/ipv4/fib_semantics.c50
1 files changed, 50 insertions, 0 deletions
diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index f8c7ec8171a8..b5c3937ca6ec 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -1457,6 +1457,56 @@ static int call_fib_nh_notifiers(struct fib_nh *fib_nh,
return NOTIFY_DONE;
}
+/* Update the PMTU of exceptions when:
+ * - the new MTU of the first hop becomes smaller than the PMTU
+ * - the old MTU was the same as the PMTU, and it limited discovery of
+ * larger MTUs on the path. With that limit raised, we can now
+ * discover larger MTUs
+ * A special case is locked exceptions, for which the PMTU is smaller
+ * than the minimal accepted PMTU:
+ * - if the new MTU is greater than the PMTU, don't make any change
+ * - otherwise, unlock and set PMTU
+ */
+static void nh_update_mtu(struct fib_nh *nh, u32 new, u32 orig)
+{
+ struct fnhe_hash_bucket *bucket;
+ int i;
+
+ bucket = rcu_dereference_protected(nh->nh_exceptions, 1);
+ if (!bucket)
+ return;
+
+ for (i = 0; i < FNHE_HASH_SIZE; i++) {
+ struct fib_nh_exception *fnhe;
+
+ for (fnhe = rcu_dereference_protected(bucket[i].chain, 1);
+ fnhe;
+ fnhe = rcu_dereference_protected(fnhe->fnhe_next, 1)) {
+ if (fnhe->fnhe_mtu_locked) {
+ if (new <= fnhe->fnhe_pmtu) {
+ fnhe->fnhe_pmtu = new;
+ fnhe->fnhe_mtu_locked = false;
+ }
+ } else if (new < fnhe->fnhe_pmtu ||
+ orig == fnhe->fnhe_pmtu) {
+ fnhe->fnhe_pmtu = new;
+ }
+ }
+ }
+}
+
+void fib_sync_mtu(struct net_device *dev, u32 orig_mtu)
+{
+ unsigned int hash = fib_devindex_hashfn(dev->ifindex);
+ struct hlist_head *head = &fib_info_devhash[hash];
+ struct fib_nh *nh;
+
+ hlist_for_each_entry(nh, head, nh_hash) {
+ if (nh->nh_dev == dev)
+ nh_update_mtu(nh, dev->mtu, orig_mtu);
+ }
+}
+
/* Event force Flags Description
* NETDEV_CHANGE 0 LINKDOWN Carrier OFF, not for scope host
* NETDEV_DOWN 0 LINKDOWN|DEAD Link down, not for scope host