diff mbox series

[net-next,v2,06/10] ipv4: Handle route deletion notification

Message ID 20191214155315.613186-7-idosch@idosch.org
State Accepted
Delegated to: David Miller
Headers show
Series Simplify IPv4 route offload API | expand

Commit Message

Ido Schimmel Dec. 14, 2019, 3:53 p.m. UTC 
From: Ido Schimmel <idosch@mellanox.com>

When a route is deleted we potentially need to promote the next route in
the FIB alias list (e.g., with an higher metric). In case we find such a
route, a replace notification is emitted. Otherwise, a delete
notification for the deleted route.

v2:
* Convert to use fib_find_alias() instead of fib_find_first_alias()

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
---
 net/ipv4/fib_trie.c | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

Comments

David Ahern Dec. 16, 2019, 4:43 p.m. UTC | #1 
On 12/14/19 8:53 AM, Ido Schimmel wrote:
> From: Ido Schimmel <idosch@mellanox.com>
> 
> When a route is deleted we potentially need to promote the next route in
> the FIB alias list (e.g., with an higher metric). In case we find such a
> route, a replace notification is emitted. Otherwise, a delete
> notification for the deleted route.
> 
> v2:
> * Convert to use fib_find_alias() instead of fib_find_first_alias()
> 
> Signed-off-by: Ido Schimmel <idosch@mellanox.com>
> ---
>  net/ipv4/fib_trie.c | 31 +++++++++++++++++++++++++++++++
>  1 file changed, 31 insertions(+)
> 

Reviewed-by: David Ahern <dsahern@gmail.com>
diff mbox series

Patch

diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
index f56945d00d7a..012aca433a91 100644
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -1570,6 +1570,36 @@  static void fib_remove_alias(struct trie *t, struct key_vector *tp,
 	node_pull_suffix(tp, fa->fa_slen);
 }
 
+static void fib_notify_alias_delete(struct net *net, u32 key,
+				    struct hlist_head *fah,
+				    struct fib_alias *fa_to_delete,
+				    struct netlink_ext_ack *extack)
+{
+	struct fib_alias *fa_next, *fa_to_notify;
+	u32 tb_id = fa_to_delete->tb_id;
+	u8 slen = fa_to_delete->fa_slen;
+	enum fib_event_type fib_event;
+
+	/* Do not notify if we do not care about the route. */
+	if (fib_find_alias(fah, slen, 0, 0, tb_id, true) != fa_to_delete)
+		return;
+
+	/* Determine if the route should be replaced by the next route in the
+	 * list.
+	 */
+	fa_next = hlist_entry_safe(fa_to_delete->fa_list.next,
+				   struct fib_alias, fa_list);
+	if (fa_next && fa_next->fa_slen == slen && fa_next->tb_id == tb_id) {
+		fib_event = FIB_EVENT_ENTRY_REPLACE_TMP;
+		fa_to_notify = fa_next;
+	} else {
+		fib_event = FIB_EVENT_ENTRY_DEL_TMP;
+		fa_to_notify = fa_to_delete;
+	}
+	call_fib_entry_notifiers(net, fib_event, key, KEYLENGTH - slen,
+				 fa_to_notify, extack);
+}
+
 /* Caller must hold RTNL. */
 int fib_table_delete(struct net *net, struct fib_table *tb,
 		     struct fib_config *cfg, struct netlink_ext_ack *extack)
@@ -1623,6 +1653,7 @@  int fib_table_delete(struct net *net, struct fib_table *tb,
 	if (!fa_to_delete)
 		return -ESRCH;
 
+	fib_notify_alias_delete(net, key, &l->leaf, fa_to_delete, extack);
 	call_fib_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, key, plen,
 				 fa_to_delete, extack);
 	rtmsg_fib(RTM_DELROUTE, htonl(key), fa_to_delete, plen, tb->tb_id,