net/ipv6: introduce fib6_info struct and helpers

Add fib6_info struct and alloc, destroy, hold and release helpers.

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

diff --git a/include/net/ip6_fib.h b/include/net/ip6_fib.h
index 159f651..630392a 100644 (file)
--- a/include/net/ip6_fib.h
+++ b/include/net/ip6_fib.h
@@ -38,6 +38,7 @@
 #endif
 
 struct rt6_info;
+struct fib6_info;
 
 struct fib6_config {
        u32             fc_table;
@@ -132,6 +133,46 @@ struct fib6_nh {
        int                     nh_weight;
 };
 
+struct fib6_info {
+       struct fib6_table               *rt6i_table;
+       struct fib6_info __rcu          *rt6_next;
+       struct fib6_node __rcu          *rt6i_node;
+
+       /* Multipath routes:
+        * siblings is a list of fib6_info that have the the same metric/weight,
+        * destination, but not the same gateway. nsiblings is just a cache
+        * to speed up lookup.
+        */
+       struct list_head                rt6i_siblings;
+       unsigned int                    rt6i_nsiblings;
+
+       atomic_t                        rt6i_ref;
+       struct inet6_dev                *rt6i_idev;
+       unsigned long                   expires;
+       struct dst_metrics              *fib6_metrics;
+#define fib6_pmtu              fib6_metrics->metrics[RTAX_MTU-1]
+
+       struct rt6key                   rt6i_dst;
+       u32                             rt6i_flags;
+       struct rt6key                   rt6i_src;
+       struct rt6key                   rt6i_prefsrc;
+
+       struct rt6_info * __percpu      *rt6i_pcpu;
+       struct rt6_exception_bucket __rcu *rt6i_exception_bucket;
+
+       u32                             rt6i_metric;
+       u8                              rt6i_protocol;
+       u8                              fib6_type;
+       u8                              exception_bucket_flushed:1,
+                                       should_flush:1,
+                                       dst_nocount:1,
+                                       dst_nopolicy:1,
+                                       dst_host:1,
+                                       unused:3;
+
+       struct fib6_nh                  fib6_nh;
+};
+
 struct rt6_info {
        struct dst_entry                dst;
        struct rt6_info __rcu           *rt6_next;
@@ -291,6 +332,20 @@ static inline void ip6_rt_put(struct rt6_info *rt)
 
 void rt6_free_pcpu(struct rt6_info *non_pcpu_rt);
 
+struct rt6_info *fib6_info_alloc(gfp_t gfp_flags);
+void fib6_info_destroy(struct rt6_info *f6i);
+
+static inline void fib6_info_hold(struct rt6_info *f6i)
+{
+       atomic_inc(&f6i->rt6i_ref);
+}
+
+static inline void fib6_info_release(struct rt6_info *f6i)
+{
+       if (f6i && atomic_dec_and_test(&f6i->rt6i_ref))
+               fib6_info_destroy(f6i);
+}
+
 static inline void rt6_hold(struct rt6_info *rt)
 {
        atomic_inc(&rt->rt6i_ref);

diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index 53df4a9..d07578d 100644 (file)
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -145,6 +145,66 @@ static __be32 addr_bit_set(const void *token, int fn_bit)
               addr[fn_bit >> 5];
 }
 
+struct rt6_info *fib6_info_alloc(gfp_t gfp_flags)
+{
+       struct rt6_info *f6i;
+
+       f6i = kzalloc(sizeof(*f6i), gfp_flags);
+       if (!f6i)
+               return NULL;
+
+       f6i->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, gfp_flags);
+       if (!f6i->rt6i_pcpu) {
+               kfree(f6i);
+               return NULL;
+       }
+
+       INIT_LIST_HEAD(&f6i->rt6i_siblings);
+       f6i->fib6_metrics = (struct dst_metrics *)&dst_default_metrics;
+
+       atomic_inc(&f6i->rt6i_ref);
+
+       return f6i;
+}
+
+void fib6_info_destroy(struct rt6_info *f6i)
+{
+       struct rt6_exception_bucket *bucket;
+
+       WARN_ON(f6i->rt6i_node);
+
+       bucket = rcu_dereference_protected(f6i->rt6i_exception_bucket, 1);
+       if (bucket) {
+               f6i->rt6i_exception_bucket = NULL;
+               kfree(bucket);
+       }
+
+       if (f6i->rt6i_pcpu) {
+               int cpu;
+
+               for_each_possible_cpu(cpu) {
+                       struct rt6_info **ppcpu_rt;
+                       struct rt6_info *pcpu_rt;
+
+                       ppcpu_rt = per_cpu_ptr(f6i->rt6i_pcpu, cpu);
+                       pcpu_rt = *ppcpu_rt;
+                       if (pcpu_rt) {
+                               dst_dev_put(&pcpu_rt->dst);
+                               dst_release(&pcpu_rt->dst);
+                               *ppcpu_rt = NULL;
+                       }
+               }
+       }
+
+       if (f6i->rt6i_idev)
+               in6_dev_put(f6i->rt6i_idev);
+       if (f6i->fib6_nh.nh_dev)
+               dev_put(f6i->fib6_nh.nh_dev);
+
+       kfree(f6i);
+}
+EXPORT_SYMBOL_GPL(fib6_info_destroy);
+
 static struct fib6_node *node_alloc(struct net *net)
 {
        struct fib6_node *fn;