inetpeer: get rid of ip_id_count

[karo-tx-linux.git] / net / ipv4 / route.c

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 4154eb76b0adc4736a4c1c266b084ab9bd458976..082239ffe34a1f42e62e9ac7901f9fe5219fdca6 100644 (file)
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -89,6 +89,7 @@
 #include <linux/rcupdate.h>
 #include <linux/times.h>
 #include <linux/slab.h>
+#include <linux/jhash.h>
 #include <net/dst.h>
 #include <net/net_namespace.h>
 #include <net/protocol.h>
@@ -456,39 +457,19 @@ static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst,
        return neigh_create(&arp_tbl, pkey, dev);
 }
 
-/*
- * Peer allocation may fail only in serious out-of-memory conditions.  However
- * we still can generate some output.
- * Random ID selection looks a bit dangerous because we have no chances to
- * select ID being unique in a reasonable period of time.
- * But broken packet identifier may be better than no packet at all.
- */
-static void ip_select_fb_ident(struct iphdr *iph)
-{
-       static DEFINE_SPINLOCK(ip_fb_id_lock);
-       static u32 ip_fallback_id;
-       u32 salt;
+atomic_t *ip_idents __read_mostly;
+EXPORT_SYMBOL(ip_idents);
 
-       spin_lock_bh(&ip_fb_id_lock);
-       salt = secure_ip_id((__force __be32)ip_fallback_id ^ iph->daddr);
-       iph->id = htons(salt & 0xFFFF);
-       ip_fallback_id = salt;
-       spin_unlock_bh(&ip_fb_id_lock);
-}
-
-void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more)
+void __ip_select_ident(struct iphdr *iph, int segs)
 {
-       struct net *net = dev_net(dst->dev);
-       struct inet_peer *peer;
+       static u32 ip_idents_hashrnd __read_mostly;
+       u32 hash, id;
 
-       peer = inet_getpeer_v4(net->ipv4.peers, iph->daddr, 1);
-       if (peer) {
-               iph->id = htons(inet_getid(peer, more));
-               inet_putpeer(peer);
-               return;
-       }
+       net_get_random_once(&ip_idents_hashrnd, sizeof(ip_idents_hashrnd));
 
-       ip_select_fb_ident(iph);
+       hash = jhash_1word((__force u32)iph->daddr, ip_idents_hashrnd);
+       id = ip_idents_reserve(hash, segs);
+       iph->id = htons(id);
 }
 EXPORT_SYMBOL(__ip_select_ident);
 
@@ -2711,6 +2692,12 @@ int __init ip_rt_init(void)
 {
        int rc = 0;
 
+       ip_idents = kmalloc(IP_IDENTS_SZ * sizeof(*ip_idents), GFP_KERNEL);
+       if (!ip_idents)
+               panic("IP: failed to allocate ip_idents\n");
+
+       prandom_bytes(ip_idents, IP_IDENTS_SZ * sizeof(*ip_idents));
+
 #ifdef CONFIG_IP_ROUTE_CLASSID
        ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct), __alignof__(struct ip_rt_acct));
        if (!ip_rt_acct)