switchdev: don't support custom ip rules, for now

Keep switchdev FIB offload model simple for now and don't allow custom ip
rules.

Signed-off-by: Scott Feldman <sfeldma@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 83 insertions, 0 deletions

diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h
index 825cb2800908..1657604c5dd3 100644
--- a/include/net/ip_fib.h
+++ b/include/net/ip_fib.h
@@ -196,6 +196,7 @@ int fib_table_delete(struct fib_table *, struct fib_config *);
 int fib_table_dump(struct fib_table *table, struct sk_buff *skb,
                    struct netlink_callback *cb);
 int fib_table_flush(struct fib_table *table);
+void fib_table_flush_external(struct fib_table *table);
 void fib_free_table(struct fib_table *tb);
 
 
@@ -308,6 +309,7 @@ static inline int fib_num_tclassid_users(struct net *net)
         return 0;
 }
 #endif
+void fib_flush_external(struct net *net);
 
 /* Exported by fib_semantics.c */
 int ip_fib_check_default(__be32 gw, struct net_device *dev);
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index 220c4b4af4cf..e067770235bf 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -144,6 +144,19 @@ static void fib_flush(struct net *net)
                 rt_cache_flush(net);
 }
 
+void fib_flush_external(struct net *net)
+{
+        struct fib_table *tb;
+        struct hlist_head *head;
+        unsigned int h;
+
+        for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
+                head = &net->ipv4.fib_table_hash[h];
+                hlist_for_each_entry(tb, head, tb_hlist)
+                        fib_table_flush_external(tb);
+        }
+}
+
 /*
  * Find address type as if only "dev" was present in the system. If
  * on_dev is NULL then all interfaces are taken into consideration.
diff --git a/net/ipv4/fib_rules.c b/net/ipv4/fib_rules.c
index d3db718be51d..190d0d00d744 100644
--- a/net/ipv4/fib_rules.c
+++ b/net/ipv4/fib_rules.c
@@ -209,6 +209,8 @@ static int fib4_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
         rule4->tos = frh->tos;
 
         net->ipv4.fib_has_custom_rules = true;
+        fib_flush_external(rule->fr_net);
+
         err = 0;
 errout:
         return err;
@@ -224,6 +226,7 @@ static void fib4_rule_delete(struct fib_rule *rule)
                 net->ipv4.fib_num_tclassid_users--;
 #endif
         net->ipv4.fib_has_custom_rules = true;
+        fib_flush_external(rule->fr_net);
 }
 
 static int fib4_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
index fae34ad4bb1a..2de43956c9d0 100644
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -1536,6 +1536,67 @@ found:
         return n;
 }
 
+/* Caller must hold RTNL */
+void fib_table_flush_external(struct fib_table *tb)
+{
+        struct trie *t = (struct trie *)tb->tb_data;
+        struct fib_alias *fa;
+        struct tnode *n, *pn;
+        unsigned long cindex;
+        unsigned char slen;
+        int found = 0;
+
+        n = rcu_dereference(t->trie);
+        if (!n)
+                return;
+
+        pn = NULL;
+        cindex = 0;
+
+        while (IS_TNODE(n)) {
+                /* record pn and cindex for leaf walking */
+                pn = n;
+                cindex = 1ul << n->bits;
+backtrace:
+                /* walk trie in reverse order */
+                do {
+                        while (!(cindex--)) {
+                                t_key pkey = pn->key;
+
+                                n = pn;
+                                pn = node_parent(n);
+
+                                /* resize completed node */
+                                resize(t, n);
+
+                                /* if we got the root we are done */
+                                if (!pn)
+                                        return;
+
+                                cindex = get_index(pkey, pn);
+                        }
+
+                        /* grab the next available node */
+                        n = tnode_get_child(pn, cindex);
+                } while (!n);
+        }
+
+        hlist_for_each_entry(fa, &n->leaf, fa_list) {
+                struct fib_info *fi = fa->fa_info;
+
+                if (fi && (fi->fib_flags & RTNH_F_EXTERNAL)) {
+                        netdev_switch_fib_ipv4_del(n->key,
+                                                   KEYLENGTH - fa->fa_slen,
+                                                   fi, fa->fa_tos,
+                                                   fa->fa_type, tb->tb_id);
+                }
+        }
+
+        /* if trie is leaf only loop is completed */
+        if (pn)
+                goto backtrace;
+}
+
 /* Caller must hold RTNL. */
 int fib_table_flush(struct fib_table *tb)
 {
diff --git a/net/switchdev/switchdev.c b/net/switchdev/switchdev.c
index 3c090f8d071b..81c4c0274b9b 100644
--- a/net/switchdev/switchdev.c
+++ b/net/switchdev/switchdev.c
@@ -242,6 +242,10 @@ EXPORT_SYMBOL(ndo_dflt_netdev_switch_port_bridge_dellink);
 int netdev_switch_fib_ipv4_add(u32 dst, int dst_len, struct fib_info *fi,
                                u8 tos, u8 type, u32 tb_id)
 {
+        /* Don't offload route if using custom ip rules */
+        if (fi->fib_net->ipv4.fib_has_custom_rules)
+                return 0;
+
         return 0;
 }
 EXPORT_SYMBOL(netdev_switch_fib_ipv4_add);