Re: [BK PATCH] [IPV6] Merge Specification Conformity Improvements

[YOSHIFUJI Hideaki / 吉藤英明 <yoshfuji@xxxxxxxxxxxxxx>]

In article <20040913155506.4c99d4c8.davem@xxxxxxxxxxxxx> (at Mon, 13 Sep 2004 
15:55:06 -0700), "David S. Miller" <davem@xxxxxxxxxxxxx> says:

> 2) rt6_dflt_{pointer,lock}
> 
>    Maybe it would be better to export a function that operates
>    on these objects rather than the objects themselves.  That
>    way we could keep them and their implementation static to
>    ip6_fib.c

Yes! I know it is silly, of course.

Well, I have a plan to remove rt6_dflt_{pointer,lock} shortly,
but anyway...

Signed-off-by: Hideaki YOSHIFUJI <yoshfuji@xxxxxxxxxxxxxx>

===== include/net/ip6_route.h 1.18 vs edited =====
--- 1.18/include/net/ip6_route.h        2004-09-11 23:50:37 +09:00
+++ edited/include/net/ip6_route.h      2004-09-14 10:01:50 +09:00
@@ -89,6 +89,8 @@
 
 extern void                    rt6_purge_dflt_routers(int lst_resort);
 
+extern void                    rt6_reset_dflt_pointer(struct rt6_info *rt);
+
 extern void                    rt6_redirect(struct in6_addr *dest,
                                             struct in6_addr *saddr,
                                             struct neighbour *neigh,
===== net/ipv6/ip6_fib.c 1.30 vs edited =====
--- 1.30/net/ipv6/ip6_fib.c     2004-09-11 23:56:06 +09:00
+++ edited/net/ipv6/ip6_fib.c   2004-09-14 10:00:33 +09:00
@@ -49,9 +49,6 @@
 
 struct rt6_statistics  rt6_stats;
 
-extern struct rt6_info *rt6_dflt_pointer;
-extern spinlock_t rt6_dflt_lock;
-
 static kmem_cache_t * fib6_node_kmem;
 
 enum fib_walk_state_t
@@ -1187,10 +1184,7 @@
        if (rt->rt6i_flags&RTF_EXPIRES && rt->rt6i_expires) {
                if (time_after(now, rt->rt6i_expires)) {
                        RT6_TRACE("expiring %p\n", rt);
-                       spin_lock_bh(&rt6_dflt_lock);
-                       if (rt == rt6_dflt_pointer)
-                               rt6_dflt_pointer = NULL;
-                       spin_unlock_bh(&rt6_dflt_lock);
+                       rt6_reset_dflt_pointer(rt);
                        return -1;
                }
                gc_args.more++;
===== net/ipv6/route.c 1.92 vs edited =====
--- 1.92/net/ipv6/route.c       2004-09-11 23:53:53 +09:00
+++ edited/net/ipv6/route.c     2004-09-14 10:10:25 +09:00
@@ -210,6 +210,16 @@
 struct rt6_info *rt6_dflt_pointer;
 spinlock_t rt6_dflt_lock = SPIN_LOCK_UNLOCKED;
 
+void rt6_reset_dflt_pointer(struct rt6_info *rt)
+{
+       spin_lock_bh(&rt6_dflt_lock);
+       if (rt == NULL || rt == rt6_dflt_pointer) {
+               RT6_TRACE("reset default router: %p->NULL\n", rt6_dflt_pointer);
+               rt6_dflt_pointer = NULL;
+       }
+       spin_unlock_bh(&rt6_dflt_lock);
+}
+
 /* Default Router Selection (RFC 2461 6.3.6) */
 static struct rt6_info *rt6_best_dflt(struct rt6_info *rt, int oif)
 {
@@ -959,9 +969,7 @@
 
        write_lock_bh(&rt6_lock);
 
-       spin_lock_bh(&rt6_dflt_lock);
-       rt6_dflt_pointer = NULL;
-       spin_unlock_bh(&rt6_dflt_lock);
+       rt6_reset_dflt_pointer(NULL);
 
        dst_release(&rt->u.dst);
 
@@ -1288,9 +1296,7 @@
                if (rt->rt6i_flags & flags) {
                        dst_hold(&rt->u.dst);
 
-                       spin_lock_bh(&rt6_dflt_lock);
-                       rt6_dflt_pointer = NULL;
-                       spin_unlock_bh(&rt6_dflt_lock);
+                       rt6_reset_dflt_pointer(NULL);
 
                        read_unlock_bh(&rt6_lock);
 


-- 
Hideaki YOSHIFUJI @ USAGI Project <yoshfuji@xxxxxxxxxxxxxx>
GPG FP: 9022 65EB 1ECF 3AD1 0BDF  80D8 4807 F894 E062 0EEA