[patch 32/38][IPV6] rt6_info - dynamically allocate rt6_info

[Daniel Lezcano]

The rt6_info structure are no longer a global static variable but
a dynamically allocated structure.
In order to facilitate future multiple instanciations of rt6_info
structures when multiple network namespaces will be supported, a
global static variable is still present as template for rt6_info
structure initialization.

Signed-off-by: Daniel Lezcano <dlezcano at fr.ibm.com>
Signed-off-by: Benjamin Thery <benjamin.thery at bull.net>
---
 net/ipv6/route.c |   67 ++++++++++++++++++++++++++++++++++++++-----------------
 1 file changed, 47 insertions(+), 20 deletions(-)

Index: linux-2.6-netns/net/ipv6/route.c
===================================================================
--- linux-2.6-netns.orig/net/ipv6/route.c
+++ linux-2.6-netns/net/ipv6/route.c
@@ -132,7 +132,7 @@ static struct dst_ops ip6_dst_blackhole_
 	.entry_size		=	sizeof(struct rt6_info),
 };
 
-static struct rt6_info __ip6_null_entry = {
+static struct rt6_info ip6_null_entry_template = {
 	.u = {
 		.dst = {
 			.__refcnt	= ATOMIC_INIT(1),
@@ -143,7 +143,6 @@ static struct rt6_info __ip6_null_entry 
 			.input		= ip6_pkt_discard,
 			.output		= ip6_pkt_discard_out,
 			.ops		= &ip6_dst_ops,
-			.path		= (struct dst_entry*)&__ip6_null_entry,
 		}
 	},
 	.rt6i_flags	= (RTF_REJECT | RTF_NONEXTHOP),
@@ -151,35 +150,34 @@ static struct rt6_info __ip6_null_entry 
 	.rt6i_ref	= ATOMIC_INIT(1),
 };
 
-struct rt6_info *ip6_null_entry = &__ip6_null_entry;
+struct rt6_info *ip6_null_entry;
 
 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 
 static int ip6_pkt_prohibit(struct sk_buff *skb);
 static int ip6_pkt_prohibit_out(struct sk_buff *skb);
 
-struct rt6_info __ip6_prohibit_entry = {
+struct rt6_info ip6_prohibit_entry_template = {
 	.u = {
 		.dst = {
-			.__refcnt	= ATOMIC_INIT(1),
-			.__use		= 1,
-			.obsolete	= -1,
-			.error		= -EACCES,
-			.metrics	= { [RTAX_HOPLIMIT - 1] = 255, },
-			.input		= ip6_pkt_prohibit,
-			.output		= ip6_pkt_prohibit_out,
-			.ops		= &ip6_dst_ops,
-			.path		= (struct dst_entry*)&__ip6_prohibit_entry,
+			.__refcnt       = ATOMIC_INIT(1),
+			.__use          = 1,
+			.obsolete       = -1,
+			.error          = -EACCES,
+			.metrics        = { [RTAX_HOPLIMIT - 1] = 255, },
+			.input          = ip6_pkt_prohibit,
+			.output         = ip6_pkt_prohibit_out,
+			.ops            = &ip6_dst_ops,
 		}
 	},
-	.rt6i_flags	= (RTF_REJECT | RTF_NONEXTHOP),
-	.rt6i_metric	= ~(u32) 0,
-	.rt6i_ref	= ATOMIC_INIT(1),
+	.rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
+	.rt6i_metric    = ~(u32) 0,
+	.rt6i_ref       = ATOMIC_INIT(1),
 };
 
-struct rt6_info *ip6_prohibit_entry = &__ip6_prohibit_entry;
+struct rt6_info *ip6_prohibit_entry;
 
-static struct rt6_info __ip6_blk_hole_entry = {
+static struct rt6_info ip6_blk_hole_entry_template = {
 	.u = {
 		.dst = {
 			.__refcnt	= ATOMIC_INIT(1),
@@ -190,7 +188,6 @@ static struct rt6_info __ip6_blk_hole_en
 			.input		= dst_discard,
 			.output		= dst_discard,
 			.ops		= &ip6_dst_ops,
-			.path		= (struct dst_entry*)&__ip6_blk_hole_entry,
 		}
 	},
 	.rt6i_flags	= (RTF_REJECT | RTF_NONEXTHOP),
@@ -198,7 +195,7 @@ static struct rt6_info __ip6_blk_hole_en
 	.rt6i_ref	= ATOMIC_INIT(1),
 };
 
-struct rt6_info *ip6_blk_hole_entry = &__ip6_blk_hole_entry;
+struct rt6_info *ip6_blk_hole_entry;
 
 #endif
 
@@ -2534,6 +2531,32 @@ static struct pernet_operations ip6_rout
 
 void __init ip6_route_init(void)
 {
+ 	ip6_null_entry = kzalloc(sizeof(*ip6_null_entry), GFP_KERNEL);
+ 	if (!ip6_null_entry)
+		panic("IPV6: cannot allocate ip6_null_entry\n");
+
+ 	memcpy(ip6_null_entry, &ip6_null_entry_template,
+	       sizeof(*ip6_null_entry));
+ 	ip6_null_entry->u.dst.path = (struct dst_entry*)ip6_null_entry;
+
+ #ifdef CONFIG_IPV6_MULTIPLE_TABLES
+ 	ip6_prohibit_entry = kzalloc(sizeof(*ip6_prohibit_entry), GFP_KERNEL);
+ 	if (!ip6_prohibit_entry)
+		panic("IPV6: cannot allocate ip6_prohibit_entry\n");
+
+ 	memcpy(ip6_prohibit_entry, &ip6_prohibit_entry_template,
+ 	       sizeof(*ip6_prohibit_entry));
+ 	ip6_prohibit_entry->u.dst.path = (struct dst_entry*)ip6_prohibit_entry;
+
+ 	ip6_blk_hole_entry = kzalloc(sizeof(*ip6_blk_hole_entry), GFP_KERNEL);
+ 	if (!ip6_blk_hole_entry)
+		panic("IPV6: panic cannot allocate ip6_blk_hole_entry\n");
+
+ 	memcpy(ip6_blk_hole_entry, &ip6_blk_hole_entry_template,
+ 	       sizeof(*ip6_blk_hole_entry));
+ 	ip6_blk_hole_entry->u.dst.path = (struct dst_entry*)ip6_blk_hole_entry;
+ #endif
+
 	ip6_dst_ops.kmem_cachep =
 		kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
 				  SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
@@ -2566,4 +2589,8 @@ void ip6_route_cleanup(void)
 	rt6_ifdown(NULL);
 	fib6_gc_cleanup();
 	kmem_cache_destroy(ip6_dst_ops.kmem_cachep);
+
+	kfree(ip6_null_entry);
+	kfree(ip6_prohibit_entry);
+	kfree(ip6_blk_hole_entry);
 }

--