ipv6: Pass fib6_result to rt6_select and find_rr_leaf

Pass fib6_result to rt6_select. Instead of returning the fib entry, it
will set f6i and nh based on the lookup.

find_rr_leaf is changed to remove the match option in favor of taking
fib6_result and having __find_rr_leaf set f6i in the result.

In the process, update fib6_info references in __find_rr_leaf to f6i names.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 43 insertions, 39 deletions

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 6bea5ac05982..a466e2e478e8 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -695,66 +695,68 @@ out:
         return rc;
 }
 
-static void __find_rr_leaf(struct fib6_info *rt_start,
+static void __find_rr_leaf(struct fib6_info *f6i_start,
                            struct fib6_info *nomatch, u32 metric,
-                           struct fib6_info **match, struct fib6_info **cont,
+                           struct fib6_result *res, struct fib6_info **cont,
                            int oif, int strict, bool *do_rr, int *mpri)
 {
-        struct fib6_info *rt;
+        struct fib6_info *f6i;
 
-        for (rt = rt_start;
-             rt && rt != nomatch;
-             rt = rcu_dereference(rt->fib6_next)) {
+        for (f6i = f6i_start;
+             f6i && f6i != nomatch;
+             f6i = rcu_dereference(f6i->fib6_next)) {
                 struct fib6_nh *nh;
 
-                if (cont && rt->fib6_metric != metric) {
-                        *cont = rt;
+                if (cont && f6i->fib6_metric != metric) {
+                        *cont = f6i;
                         return;
                 }
 
-                if (fib6_check_expired(rt))
+                if (fib6_check_expired(f6i))
                         continue;
 
-                nh = &rt->fib6_nh;
-                if (find_match(nh, rt->fib6_flags, oif, strict, mpri, do_rr))
-                        *match = rt;
+                nh = &f6i->fib6_nh;
+                if (find_match(nh, f6i->fib6_flags, oif, strict, mpri, do_rr)) {
+                        res->f6i = f6i;
+                        res->nh = nh;
+                }
         }
 }
 
-static struct fib6_info *find_rr_leaf(struct fib6_node *fn,
-                                      struct fib6_info *leaf,
-                                      struct fib6_info *rr_head,
-                                      u32 metric, int oif, int strict,
-                                      bool *do_rr)
+static void find_rr_leaf(struct fib6_node *fn, struct fib6_info *leaf,
+                         struct fib6_info *rr_head, int oif, int strict,
+                         bool *do_rr, struct fib6_result *res)
 {
-        struct fib6_info *match = NULL, *cont = NULL;
+        u32 metric = rr_head->fib6_metric;
+        struct fib6_info *cont = NULL;
         int mpri = -1;
 
-        __find_rr_leaf(rr_head, NULL, metric, &match, &cont,
+        __find_rr_leaf(rr_head, NULL, metric, res, &cont,
                        oif, strict, do_rr, &mpri);
 
-        __find_rr_leaf(leaf, rr_head, metric, &match, &cont,
+        __find_rr_leaf(leaf, rr_head, metric, res, &cont,
                        oif, strict, do_rr, &mpri);
 
-        if (match || !cont)
-                return match;
+        if (res->f6i || !cont)
+                return;
 
-        __find_rr_leaf(cont, NULL, metric, &match, NULL,
+        __find_rr_leaf(cont, NULL, metric, res, NULL,
                        oif, strict, do_rr, &mpri);
-
-        return match;
 }
 
-static struct fib6_info *rt6_select(struct net *net, struct fib6_node *fn,
-                                   int oif, int strict)
+static void rt6_select(struct net *net, struct fib6_node *fn, int oif,
+                       struct fib6_result *res, int strict)
 {
         struct fib6_info *leaf = rcu_dereference(fn->leaf);
-        struct fib6_info *match, *rt0;
+        struct fib6_info *rt0;
         bool do_rr = false;
         int key_plen;
 
+        /* make sure this function or its helpers sets f6i */
+        res->f6i = NULL;
+
         if (!leaf || leaf == net->ipv6.fib6_null_entry)
-                return net->ipv6.fib6_null_entry;
+                goto out;
 
         rt0 = rcu_dereference(fn->rr_ptr);
         if (!rt0)
@@ -771,11 +773,9 @@ static struct fib6_info *rt6_select(struct net *net, struct fib6_node *fn,
                 key_plen = rt0->fib6_src.plen;
 #endif
         if (fn->fn_bit != key_plen)
-                return net->ipv6.fib6_null_entry;
-
-        match = find_rr_leaf(fn, leaf, rt0, rt0->fib6_metric, oif, strict,
-                             &do_rr);
+                goto out;
 
+        find_rr_leaf(fn, leaf, rt0, oif, strict, &do_rr, res);
         if (do_rr) {
                 struct fib6_info *next = rcu_dereference(rt0->fib6_next);
 
@@ -792,7 +792,11 @@ static struct fib6_info *rt6_select(struct net *net, struct fib6_node *fn,
                 }
         }
 
-        return match ? match : net->ipv6.fib6_null_entry;
+out:
+        if (!res->f6i) {
+                res->f6i = net->ipv6.fib6_null_entry;
+                res->nh = &res->f6i->fib6_nh;
+        }
 }
 
 static bool rt6_is_gw_or_nonexthop(const struct fib6_result *res)
@@ -1839,7 +1843,7 @@ struct fib6_info *fib6_table_lookup(struct net *net, struct fib6_table *table,
                                     int oif, struct flowi6 *fl6, int strict)
 {
         struct fib6_node *fn, *saved_fn;
-        struct fib6_info *f6i;
+        struct fib6_result res;
 
         fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
         saved_fn = fn;
@@ -1848,8 +1852,8 @@ struct fib6_info *fib6_table_lookup(struct net *net, struct fib6_table *table,
                 oif = 0;
 
 redo_rt6_select:
-        f6i = rt6_select(net, fn, oif, strict);
-        if (f6i == net->ipv6.fib6_null_entry) {
+        rt6_select(net, fn, oif, &res, strict);
+        if (res.f6i == net->ipv6.fib6_null_entry) {
                 fn = fib6_backtrack(fn, &fl6->saddr);
                 if (fn)
                         goto redo_rt6_select;
@@ -1861,9 +1865,9 @@ redo_rt6_select:
                 }
         }
 
-        trace_fib6_table_lookup(net, f6i, table, fl6);
+        trace_fib6_table_lookup(net, res.f6i, table, fl6);
 
-        return f6i;
+        return res.f6i;
 }
 
 struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,