[PATCH 1/2] ipv4 routing: splitting of ip_route_[in|out]put_slow, 2.6.10-rc3
From: Einar Lueck <lkml@xxxxxxxxxxxxxx>
This patch splits up ip_route_[in|out]put_slow in inlined functions. Basic idea: * improve overall comprehensibility * allow for an easier application of patch for improved multipath support (refer to the subsequent patch)
We consider this patch and the subsequent patch as added value for the linux kernel. We hope you have any suggestions or have an opinion concerning the application of these patches.
Regards
Einar.
Signed-off-by: Einar Lueck <lkml@xxxxxxxxxxxxxx>
diff -ruN linux-2.6.9/net/ipv4/route.c linux-2.6.9.split/net/ipv4/route.c
--- linux-2.6.9/net/ipv4/route.c 2004-12-15 12:03:59.000000000 +0100
+++ linux-2.6.9.split/net/ipv4/route.c 2004-12-15 12:05:32.000000000 +0100
@@ -104,6 +104,9 @@
#include <linux/sysctl.h>
#endif
+#define RT_FL_TOS(oldflp) \
+ ((u32)(oldflp->fl4_tos & (IPTOS_RT_MASK | RTO_ONLINK)))
+
#define IP_MAX_MTU 0xFFF0
#define RT_GC_TIMEOUT (300*HZ)
@@ -143,6 +146,7 @@
static void ipv4_link_failure(struct sk_buff *skb);
static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
static int rt_garbage_collect(void);
+static inline int compare_keys(struct flowi *fl1, struct flowi *fl2);
static struct dst_ops ipv4_dst_ops = {
@@ -1533,6 +1537,169 @@
return -EINVAL;
}
+
+static void ip_handle_martian_source(struct net_device *dev,
+ struct in_device *in_dev,
+ struct sk_buff *skb,
+ u32 daddr,
+ u32 saddr)
+{
+ RT_CACHE_STAT_INC(in_martian_src);
+#ifdef CONFIG_IP_ROUTE_VERBOSE
+ if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) {
+ /*
+ * RFC1812 recommendation, if source is martian,
+ * the only hint is MAC header.
+ */
+ printk(KERN_WARNING "martian source %u.%u.%u.%u from "
+ "%u.%u.%u.%u, on dev %s\n",
+ NIPQUAD(daddr), NIPQUAD(saddr), dev->name);
+ if (dev->hard_header_len) {
+ int i;
+ unsigned char *p = skb->mac.raw;
+ printk(KERN_WARNING "ll header: ");
+ for (i = 0; i < dev->hard_header_len; i++, p++) {
+ printk("%02x", *p);
+ if (i < (dev->hard_header_len - 1))
+ printk(":");
+ }
+ printk("\n");
+ }
+ }
+#endif
+}
+
+static inline int __mkroute_input(struct sk_buff *skb,
+ struct fib_result* res,
+ struct in_device *in_dev,
+ u32 daddr, u32 saddr, u32 tos,
+ struct rtable **result)
+{
+
+ struct rtable *rth;
+ int err;
+ struct in_device *out_dev;
+ unsigned flags = 0;
+ u32 spec_dst, itag;
+
+ /* get a working reference to the output device */
+ out_dev = in_dev_get(FIB_RES_DEV(*res));
+ if (out_dev == NULL) {
+ if (net_ratelimit())
+ printk(KERN_CRIT "Bug in ip_route_input" \
+ "_slow(). Please, report\n");
+ return -EINVAL;
+ }
+
+
+ err = fib_validate_source(saddr, daddr, tos, FIB_RES_OIF(*res),
+ in_dev->dev, &spec_dst, &itag);
+ if (err < 0) {
+ ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr,
+ saddr);
+
+ err = -EINVAL;
+ goto cleanup;
+ }
+
+ if (err)
+ flags |= RTCF_DIRECTSRC;
+
+ if (out_dev == in_dev && err && !(flags & (RTCF_NAT | RTCF_MASQ)) &&
+ (IN_DEV_SHARED_MEDIA(out_dev) ||
+ inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res))))
+ flags |= RTCF_DOREDIRECT;
+
+ if (skb->protocol != htons(ETH_P_IP)) {
+ /* Not IP (i.e. ARP). Do not create route, if it is
+ * invalid for proxy arp. DNAT routes are always valid.
+ */
+ if (out_dev == in_dev && !(flags & RTCF_DNAT)) {
+ err = -EINVAL;
+ goto cleanup;
+ }
+ }
+
+
+ rth = dst_alloc(&ipv4_dst_ops);
+ if (!rth) {
+ err = -ENOBUFS;
+ goto cleanup;
+ }
+
+ rth->u.dst.flags= DST_HOST;
+ if (in_dev->cnf.no_policy)
+ rth->u.dst.flags |= DST_NOPOLICY;
+ if (in_dev->cnf.no_xfrm)
+ rth->u.dst.flags |= DST_NOXFRM;
+ rth->fl.fl4_dst = daddr;
+ rth->rt_dst = daddr;
+ rth->fl.fl4_tos = tos;
+#ifdef CONFIG_IP_ROUTE_FWMARK
+ rth->fl.fl4_fwmark= skb->nfmark;
+#endif
+ rth->fl.fl4_src = saddr;
+ rth->rt_src = saddr;
+ rth->rt_gateway = daddr;
+ rth->rt_iif =
+ rth->fl.iif = in_dev->dev->ifindex;
+ rth->u.dst.dev = (out_dev)->dev;
+ dev_hold(rth->u.dst.dev);
+ rth->idev = in_dev_get(rth->u.dst.dev);
+ rth->fl.oif = 0;
+ rth->rt_spec_dst= spec_dst;
+
+ rth->u.dst.input = ip_forward;
+ rth->u.dst.output = ip_output;
+
+ rt_set_nexthop(rth, res, itag);
+
+ rth->rt_flags = flags;
+
+ *result = rth;
+ err = 0;
+ cleanup:
+ /* release the working reference to the output device */
+ in_dev_put(out_dev);
+ return err;
+}
+
+static inline int ip_mkroute_input_def(struct sk_buff *skb,
+ struct fib_result* res,
+ const struct flowi *fl,
+ struct in_device *in_dev,
+ u32 daddr, u32 saddr, u32 tos)
+{
+ struct rtable* rth;
+ int err;
+ unsigned hash;
+
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+ if (res->fi->fib_nhs > 1 && fl->oif == 0)
+ fib_select_multipath(fl, res);
+#endif
+
+ /* create a routing cache entry */
+ err = __mkroute_input( skb, res, in_dev, daddr, saddr, tos, &rth );
+ if ( err )
+ return err;
+ atomic_set(&rth->u.dst.__refcnt, 1);
+
+ /* put it into the cache */
+ hash = rt_hash_code(daddr, saddr ^ (fl->iif << 5), tos);
+ return rt_intern_hash(hash, rth, (struct rtable**)&skb->dst);
+}
+
+static inline int ip_mkroute_input(struct sk_buff *skb,
+ struct fib_result* res,
+ const struct flowi *fl,
+ struct in_device *in_dev,
+ u32 daddr, u32 saddr, u32 tos)
+{
+ return ip_mkroute_input_def(skb, res, fl, in_dev, daddr, saddr, tos);
+}
+
+
/*
* NOTE. We drop all the packets that has local source
* addresses, because every properly looped back packet
@@ -1544,11 +1711,10 @@
*/
static int ip_route_input_slow(struct sk_buff *skb, u32 daddr, u32 saddr,
- u8 tos, struct net_device *dev)
+ u8 tos, struct net_device *dev)
{
struct fib_result res;
struct in_device *in_dev = in_dev_get(dev);
- struct in_device *out_dev = NULL;
struct flowi fl = { .nl_u = { .ip4_u =
{ .daddr = daddr,
.saddr = saddr,
@@ -1572,8 +1738,6 @@
if (!in_dev)
goto out;
- hash = rt_hash_code(daddr, saddr ^ (fl.iif << 5), tos);
-
/* Check for the most weird martians, which can be not detected
by fib_lookup.
*/
@@ -1626,79 +1790,14 @@
if (res.type != RTN_UNICAST)
goto martian_destination;
-#ifdef CONFIG_IP_ROUTE_MULTIPATH
- if (res.fi->fib_nhs > 1 && fl.oif == 0)
- fib_select_multipath(&fl, &res);
-#endif
- out_dev = in_dev_get(FIB_RES_DEV(res));
- if (out_dev == NULL) {
- if (net_ratelimit())
- printk(KERN_CRIT "Bug in ip_route_input_slow(). "
- "Please, report\n");
- goto e_inval;
- }
-
- err = fib_validate_source(saddr, daddr, tos, FIB_RES_OIF(res), dev,
- &spec_dst, &itag);
- if (err < 0)
- goto martian_source;
-
- if (err)
- flags |= RTCF_DIRECTSRC;
-
- if (out_dev == in_dev && err && !(flags & (RTCF_NAT | RTCF_MASQ)) &&
- (IN_DEV_SHARED_MEDIA(out_dev) ||
- inet_addr_onlink(out_dev, saddr, FIB_RES_GW(res))))
- flags |= RTCF_DOREDIRECT;
-
- if (skb->protocol != htons(ETH_P_IP)) {
- /* Not IP (i.e. ARP). Do not create route, if it is
- * invalid for proxy arp. DNAT routes are always valid.
- */
- if (out_dev == in_dev && !(flags & RTCF_DNAT))
- goto e_inval;
- }
-
- rth = dst_alloc(&ipv4_dst_ops);
- if (!rth)
+ err = ip_mkroute_input(skb, &res, &fl, in_dev, daddr, saddr, tos);
+ if ( err == -ENOBUFS )
goto e_nobufs;
-
- atomic_set(&rth->u.dst.__refcnt, 1);
- rth->u.dst.flags= DST_HOST;
- if (in_dev->cnf.no_policy)
- rth->u.dst.flags |= DST_NOPOLICY;
- if (in_dev->cnf.no_xfrm)
- rth->u.dst.flags |= DST_NOXFRM;
- rth->fl.fl4_dst = daddr;
- rth->rt_dst = daddr;
- rth->fl.fl4_tos = tos;
-#ifdef CONFIG_IP_ROUTE_FWMARK
- rth->fl.fl4_fwmark= skb->nfmark;
-#endif
- rth->fl.fl4_src = saddr;
- rth->rt_src = saddr;
- rth->rt_gateway = daddr;
- rth->rt_iif =
- rth->fl.iif = dev->ifindex;
- rth->u.dst.dev = out_dev->dev;
- dev_hold(rth->u.dst.dev);
- rth->idev = in_dev_get(rth->u.dst.dev);
- rth->fl.oif = 0;
- rth->rt_spec_dst= spec_dst;
-
- rth->u.dst.input = ip_forward;
- rth->u.dst.output = ip_output;
-
- rt_set_nexthop(rth, &res, itag);
-
- rth->rt_flags = flags;
-
-intern:
- err = rt_intern_hash(hash, rth, (struct rtable**)&skb->dst);
+ if ( err == -EINVAL )
+ goto e_inval;
+
done:
in_dev_put(in_dev);
- if (out_dev)
- in_dev_put(out_dev);
if (free_res)
fib_res_put(&res);
out: return err;
@@ -1758,7 +1857,9 @@
rth->rt_flags &= ~RTCF_LOCAL;
}
rth->rt_type = res.type;
- goto intern;
+ hash = rt_hash_code(daddr, saddr ^ (fl.iif << 5), tos);
+ err = rt_intern_hash(hash, rth, (struct rtable**)&skb->dst);
+ goto done;
no_route:
RT_CACHE_STAT_INC(in_no_route);
@@ -1786,30 +1887,7 @@
goto done;
martian_source:
-
- RT_CACHE_STAT_INC(in_martian_src);
-#ifdef CONFIG_IP_ROUTE_VERBOSE
- if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) {
- /*
- * RFC1812 recommendation, if source is martian,
- * the only hint is MAC header.
- */
- printk(KERN_WARNING "martian source %u.%u.%u.%u from "
- "%u.%u.%u.%u, on dev %s\n",
- NIPQUAD(daddr), NIPQUAD(saddr), dev->name);
- if (dev->hard_header_len) {
- int i;
- unsigned char *p = skb->mac.raw;
- printk(KERN_WARNING "ll header: ");
- for (i = 0; i < dev->hard_header_len; i++, p++) {
- printk("%02x", *p);
- if (i < (dev->hard_header_len - 1))
- printk(":");
- }
- printk("\n");
- }
- }
-#endif
+ ip_handle_martian_source(dev, in_dev, skb, daddr, saddr);
goto e_inval;
}
@@ -1880,13 +1958,166 @@
return ip_route_input_slow(skb, daddr, saddr, tos, dev);
}
+static inline int __mkroute_output(struct rtable **result,
+ struct fib_result* res,
+ const struct flowi *fl,
+ const struct flowi *oldflp,
+ struct net_device *dev_out,
+ unsigned flags)
+{
+ struct rtable *rth;
+ struct in_device *in_dev;
+ u32 tos = RT_FL_TOS(oldflp);
+ int err = 0;
+
+ if (LOOPBACK(fl->fl4_src) && !(dev_out->flags&IFF_LOOPBACK))
+ return -EINVAL;
+
+ if (fl->fl4_dst == 0xFFFFFFFF)
+ res->type = RTN_BROADCAST;
+ else if (MULTICAST(fl->fl4_dst))
+ res->type = RTN_MULTICAST;
+ else if (BADCLASS(fl->fl4_dst) || ZERONET(fl->fl4_dst))
+ return -EINVAL;
+
+ if (dev_out->flags & IFF_LOOPBACK)
+ flags |= RTCF_LOCAL;
+
+ /* get work reference to inet device */
+ in_dev = in_dev_get(dev_out);
+ if (!in_dev)
+ return -EINVAL;
+
+ if (res->type == RTN_BROADCAST) {
+ flags |= RTCF_BROADCAST | RTCF_LOCAL;
+ if (res->fi) {
+ fib_info_put(res->fi);
+ res->fi = NULL;
+ }
+ } else if (res->type == RTN_MULTICAST) {
+ flags |= RTCF_MULTICAST|RTCF_LOCAL;
+ if (!ip_check_mc(in_dev, oldflp->fl4_dst, oldflp->fl4_src,
+ oldflp->proto))
+ flags &= ~RTCF_LOCAL;
+ /* If multicast route do not exist use
+ default one, but do not gateway in this case.
+ Yes, it is hack.
+ */
+ if (res->fi && res->prefixlen < 4) {
+ fib_info_put(res->fi);
+ res->fi = NULL;
+ }
+ }
+
+
+ rth = dst_alloc(&ipv4_dst_ops);
+ if (!rth) {
+ err = -ENOBUFS;
+ goto cleanup;
+ }
+
+ rth->u.dst.flags= DST_HOST;
+ if (in_dev->cnf.no_xfrm)
+ rth->u.dst.flags |= DST_NOXFRM;
+ if (in_dev->cnf.no_policy)
+ rth->u.dst.flags |= DST_NOPOLICY;
+
+ rth->fl.fl4_dst = oldflp->fl4_dst;
+ rth->fl.fl4_tos = tos;
+ rth->fl.fl4_src = oldflp->fl4_src;
+ rth->fl.oif = oldflp->oif;
+#ifdef CONFIG_IP_ROUTE_FWMARK
+ rth->fl.fl4_fwmark= oldflp->fl4_fwmark;
+#endif
+ rth->rt_dst = fl->fl4_dst;
+ rth->rt_src = fl->fl4_src;
+ rth->rt_iif = oldflp->oif ? : dev_out->ifindex;
+ /* get references to the devices that are to be hold by the routing
+ cache entry */
+ rth->u.dst.dev = dev_out;
+ dev_hold(dev_out);
+ rth->idev = in_dev_get(dev_out);
+ rth->rt_gateway = fl->fl4_dst;
+ rth->rt_spec_dst= fl->fl4_src;
+
+ rth->u.dst.output=ip_output;
+
+ RT_CACHE_STAT_INC(out_slow_tot);
+
+ if (flags & RTCF_LOCAL) {
+ rth->u.dst.input = ip_local_deliver;
+ rth->rt_spec_dst = fl->fl4_dst;
+ }
+ if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) {
+ rth->rt_spec_dst = fl->fl4_src;
+ if (flags & RTCF_LOCAL &&
+ !(dev_out->flags & IFF_LOOPBACK)) {
+ rth->u.dst.output = ip_mc_output;
+ RT_CACHE_STAT_INC(out_slow_mc);
+ }
+#ifdef CONFIG_IP_MROUTE
+ if (res->type == RTN_MULTICAST) {
+ if (IN_DEV_MFORWARD(in_dev) &&
+ !LOCAL_MCAST(oldflp->fl4_dst)) {
+ rth->u.dst.input = ip_mr_input;
+ rth->u.dst.output = ip_mc_output;
+ }
+ }
+#endif
+ }
+
+ rt_set_nexthop(rth, res, 0);
+
+ rth->rt_flags = flags;
+
+ *result = rth;
+ cleanup:
+ /* release work reference to inet device */
+ in_dev_put(in_dev);
+
+ return err;
+}
+
+static inline int ip_mkroute_output_def(struct rtable **rp,
+ struct fib_result* res,
+ const struct flowi *fl,
+ const struct flowi *oldflp,
+ struct net_device *dev_out,
+ unsigned flags)
+{
+ struct rtable *rth;
+ int err = __mkroute_output(&rth, res, fl, oldflp, dev_out, flags);
+ unsigned hash;
+ if ( err == 0 ) {
+ u32 tos = RT_FL_TOS(oldflp);
+
+ atomic_set(&rth->u.dst.__refcnt, 1);
+
+ hash = rt_hash_code(oldflp->fl4_dst,
+ oldflp->fl4_src ^ (oldflp->oif << 5), tos);
+ err = rt_intern_hash(hash, rth, rp);
+ }
+
+ return err;
+}
+
+static inline int ip_mkroute_output(struct rtable** rp,
+ struct fib_result* res,
+ const struct flowi *fl,
+ const struct flowi *oldflp,
+ struct net_device *dev_out,
+ unsigned flags)
+{
+ return ip_mkroute_output_def(rp, res, fl, oldflp, dev_out, flags);
+}
+
/*
* Major route resolver routine.
*/
static int ip_route_output_slow(struct rtable **rp, const struct flowi *oldflp)
{
- u32 tos = oldflp->fl4_tos & (IPTOS_RT_MASK | RTO_ONLINK);
+ u32 tos = RT_FL_TOS(oldflp);
struct flowi fl = { .nl_u = { .ip4_u =
{ .daddr = oldflp->fl4_dst,
.saddr = oldflp->fl4_src,
@@ -1902,10 +2133,7 @@
.oif = oldflp->oif };
struct fib_result res;
unsigned flags = 0;
- struct rtable *rth;
struct net_device *dev_out = NULL;
- struct in_device *in_dev = NULL;
- unsigned hash;
int free_res = 0;
int err;
@@ -2065,116 +2293,13 @@
fl.oif = dev_out->ifindex;
make_route:
- if (LOOPBACK(fl.fl4_src) && !(dev_out->flags&IFF_LOOPBACK))
- goto e_inval;
+ err = ip_mkroute_output(rp, &res, &fl, oldflp, dev_out, flags);
- if (fl.fl4_dst == 0xFFFFFFFF)
- res.type = RTN_BROADCAST;
- else if (MULTICAST(fl.fl4_dst))
- res.type = RTN_MULTICAST;
- else if (BADCLASS(fl.fl4_dst) || ZERONET(fl.fl4_dst))
- goto e_inval;
-
- if (dev_out->flags & IFF_LOOPBACK)
- flags |= RTCF_LOCAL;
-
- in_dev = in_dev_get(dev_out);
- if (!in_dev)
- goto e_inval;
-
- if (res.type == RTN_BROADCAST) {
- flags |= RTCF_BROADCAST | RTCF_LOCAL;
- if (res.fi) {
- fib_info_put(res.fi);
- res.fi = NULL;
- }
- } else if (res.type == RTN_MULTICAST) {
- flags |= RTCF_MULTICAST|RTCF_LOCAL;
- if (!ip_check_mc(in_dev, oldflp->fl4_dst, oldflp->fl4_src, oldflp->proto))
- flags &= ~RTCF_LOCAL;
- /* If multicast route do not exist use
- default one, but do not gateway in this case.
- Yes, it is hack.
- */
- if (res.fi && res.prefixlen < 4) {
- fib_info_put(res.fi);
- res.fi = NULL;
- }
- }
-
- rth = dst_alloc(&ipv4_dst_ops);
- if (!rth)
- goto e_nobufs;
-
- atomic_set(&rth->u.dst.__refcnt, 1);
- rth->u.dst.flags= DST_HOST;
- if (in_dev->cnf.no_xfrm)
- rth->u.dst.flags |= DST_NOXFRM;
- if (in_dev->cnf.no_policy)
- rth->u.dst.flags |= DST_NOPOLICY;
- rth->fl.fl4_dst = oldflp->fl4_dst;
- rth->fl.fl4_tos = tos;
- rth->fl.fl4_src = oldflp->fl4_src;
- rth->fl.oif = oldflp->oif;
-#ifdef CONFIG_IP_ROUTE_FWMARK
- rth->fl.fl4_fwmark= oldflp->fl4_fwmark;
-#endif
- rth->rt_dst = fl.fl4_dst;
- rth->rt_src = fl.fl4_src;
- rth->rt_iif = oldflp->oif ? : dev_out->ifindex;
- rth->u.dst.dev = dev_out;
- dev_hold(dev_out);
- rth->idev = in_dev_get(dev_out);
- rth->rt_gateway = fl.fl4_dst;
- rth->rt_spec_dst= fl.fl4_src;
-
- rth->u.dst.output=ip_output;
-
- RT_CACHE_STAT_INC(out_slow_tot);
-
- if (flags & RTCF_LOCAL) {
- rth->u.dst.input = ip_local_deliver;
- rth->rt_spec_dst = fl.fl4_dst;
- }
- if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) {
- rth->rt_spec_dst = fl.fl4_src;
- if (flags & RTCF_LOCAL && !(dev_out->flags & IFF_LOOPBACK)) {
- rth->u.dst.output = ip_mc_output;
- RT_CACHE_STAT_INC(out_slow_mc);
- }
-#ifdef CONFIG_IP_MROUTE
- if (res.type == RTN_MULTICAST) {
- if (IN_DEV_MFORWARD(in_dev) &&
- !LOCAL_MCAST(oldflp->fl4_dst)) {
- rth->u.dst.input = ip_mr_input;
- rth->u.dst.output = ip_mc_output;
- }
- }
-#endif
- }
-
- rt_set_nexthop(rth, &res, 0);
-
-
- rth->rt_flags = flags;
-
- hash = rt_hash_code(oldflp->fl4_dst, oldflp->fl4_src ^ (oldflp->oif << 5), tos);
- err = rt_intern_hash(hash, rth, rp);
-done:
if (free_res)
fib_res_put(&res);
if (dev_out)
dev_put(dev_out);
- if (in_dev)
- in_dev_put(in_dev);
out: return err;
-
-e_inval:
- err = -EINVAL;
- goto done;
-e_nobufs:
- err = -ENOBUFS;
- goto done;
}
int __ip_route_output_key(struct rtable **rp, const struct flowi *flp)
