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ipv4: Use caller's on-stack flowi as-is in output route lookups.
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Signed-off-by: David S. Miller <davem@davemloft.net>
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@davem330
davem330 committed Apr 29, 2011
1 parent cf91166 commit 813b3b5
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Showing 2 changed files with 81 additions and 79 deletions.
2 changes: 1 addition & 1 deletion include/net/route.h
View file
Expand Up @@ -115,7 +115,7 @@ extern void ip_rt_redirect(__be32 old_gw, __be32 dst, __be32 new_gw,
__be32 src, struct net_device *dev);
extern void rt_cache_flush(struct net *net, int how);
extern void rt_cache_flush_batch(struct net *net);
extern struct rtable *__ip_route_output_key(struct net *, const struct flowi4 *flp);
extern struct rtable *__ip_route_output_key(struct net *, struct flowi4 *flp);
extern struct rtable *ip_route_output_flow(struct net *, struct flowi4 *flp,
struct sock *sk);
extern struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig);
Expand Down
158 changes: 80 additions & 78 deletions net/ipv4/route.c
View file
Expand Up @@ -1767,7 +1767,7 @@ static unsigned int ipv4_default_mtu(const struct dst_entry *dst)
return mtu;
}

static void rt_init_metrics(struct rtable *rt, const struct flowi4 *oldflp4,
static void rt_init_metrics(struct rtable *rt, const struct flowi4 *fl4,
struct fib_info *fi)
{
struct inet_peer *peer;
Expand All @@ -1776,7 +1776,7 @@ static void rt_init_metrics(struct rtable *rt, const struct flowi4 *oldflp4,
/* If a peer entry exists for this destination, we must hook
* it up in order to get at cached metrics.
*/
if (oldflp4 && (oldflp4->flowi4_flags & FLOWI_FLAG_PRECOW_METRICS))
if (fl4 && (fl4->flowi4_flags & FLOWI_FLAG_PRECOW_METRICS))
create = 1;

rt->peer = peer = inet_getpeer_v4(rt->rt_dst, create);
Expand All @@ -1803,7 +1803,7 @@ static void rt_init_metrics(struct rtable *rt, const struct flowi4 *oldflp4,
}
}

static void rt_set_nexthop(struct rtable *rt, const struct flowi4 *oldflp4,
static void rt_set_nexthop(struct rtable *rt, const struct flowi4 *fl4,
const struct fib_result *res,
struct fib_info *fi, u16 type, u32 itag)
{
Expand All @@ -1813,7 +1813,7 @@ static void rt_set_nexthop(struct rtable *rt, const struct flowi4 *oldflp4,
if (FIB_RES_GW(*res) &&
FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
rt->rt_gateway = FIB_RES_GW(*res);
rt_init_metrics(rt, oldflp4, fi);
rt_init_metrics(rt, fl4, fi);
#ifdef CONFIG_IP_ROUTE_CLASSID
dst->tclassid = FIB_RES_NH(*res).nh_tclassid;
#endif
Expand Down Expand Up @@ -2354,12 +2354,12 @@ EXPORT_SYMBOL(ip_route_input_common);
/* called with rcu_read_lock() */
static struct rtable *__mkroute_output(const struct fib_result *res,
const struct flowi4 *fl4,
const struct flowi4 *oldflp4,
struct net_device *dev_out,
__be32 orig_daddr, __be32 orig_saddr,
int orig_oif, struct net_device *dev_out,
unsigned int flags)
{
struct fib_info *fi = res->fi;
u32 tos = RT_FL_TOS(oldflp4);
u32 tos = RT_FL_TOS(fl4);
struct in_device *in_dev;
u16 type = res->type;
struct rtable *rth;
Expand All @@ -2386,8 +2386,8 @@ static struct rtable *__mkroute_output(const struct fib_result *res,
fi = NULL;
} else if (type == RTN_MULTICAST) {
flags |= RTCF_MULTICAST | RTCF_LOCAL;
if (!ip_check_mc_rcu(in_dev, oldflp4->daddr, oldflp4->saddr,
oldflp4->flowi4_proto))
if (!ip_check_mc_rcu(in_dev, fl4->daddr, fl4->saddr,
fl4->flowi4_proto))
flags &= ~RTCF_LOCAL;
/* If multicast route do not exist use
* default one, but do not gateway in this case.
Expand All @@ -2405,18 +2405,18 @@ static struct rtable *__mkroute_output(const struct fib_result *res,

rth->dst.output = ip_output;

rth->rt_key_dst = oldflp4->daddr;
rth->rt_key_src = oldflp4->saddr;
rth->rt_key_dst = orig_daddr;
rth->rt_key_src = orig_saddr;
rth->rt_genid = rt_genid(dev_net(dev_out));
rth->rt_flags = flags;
rth->rt_type = type;
rth->rt_tos = tos;
rth->rt_dst = fl4->daddr;
rth->rt_src = fl4->saddr;
rth->rt_route_iif = 0;
rth->rt_iif = oldflp4->flowi4_oif ? : dev_out->ifindex;
rth->rt_oif = oldflp4->flowi4_oif;
rth->rt_mark = oldflp4->flowi4_mark;
rth->rt_iif = orig_oif ? : dev_out->ifindex;
rth->rt_oif = orig_oif;
rth->rt_mark = fl4->flowi4_mark;
rth->rt_gateway = fl4->daddr;
rth->rt_spec_dst= fl4->saddr;
rth->rt_peer_genid = 0;
Expand All @@ -2439,15 +2439,15 @@ static struct rtable *__mkroute_output(const struct fib_result *res,
#ifdef CONFIG_IP_MROUTE
if (type == RTN_MULTICAST) {
if (IN_DEV_MFORWARD(in_dev) &&
!ipv4_is_local_multicast(oldflp4->daddr)) {
!ipv4_is_local_multicast(fl4->daddr)) {
rth->dst.input = ip_mr_input;
rth->dst.output = ip_mc_output;
}
}
#endif
}

rt_set_nexthop(rth, oldflp4, res, fi, type, 0);
rt_set_nexthop(rth, fl4, res, fi, type, 0);

return rth;
}
Expand All @@ -2457,36 +2457,37 @@ static struct rtable *__mkroute_output(const struct fib_result *res,
* called with rcu_read_lock();
*/

static struct rtable *ip_route_output_slow(struct net *net,
const struct flowi4 *oldflp4)
static struct rtable *ip_route_output_slow(struct net *net, struct flowi4 *fl4)
{
u32 tos = RT_FL_TOS(oldflp4);
struct flowi4 fl4;
struct fib_result res;
unsigned int flags = 0;
struct net_device *dev_out = NULL;
u32 tos = RT_FL_TOS(fl4);
unsigned int flags = 0;
struct fib_result res;
struct rtable *rth;
__be32 orig_daddr;
__be32 orig_saddr;
int orig_oif;

res.fi = NULL;
#ifdef CONFIG_IP_MULTIPLE_TABLES
res.r = NULL;
#endif

fl4.flowi4_oif = oldflp4->flowi4_oif;
fl4.flowi4_iif = net->loopback_dev->ifindex;
fl4.flowi4_mark = oldflp4->flowi4_mark;
fl4.daddr = oldflp4->daddr;
fl4.saddr = oldflp4->saddr;
fl4.flowi4_tos = tos & IPTOS_RT_MASK;
fl4.flowi4_scope = ((tos & RTO_ONLINK) ?
RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);
orig_daddr = fl4->daddr;
orig_saddr = fl4->saddr;
orig_oif = fl4->flowi4_oif;

fl4->flowi4_iif = net->loopback_dev->ifindex;
fl4->flowi4_tos = tos & IPTOS_RT_MASK;
fl4->flowi4_scope = ((tos & RTO_ONLINK) ?
RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);

rcu_read_lock();
if (oldflp4->saddr) {
if (fl4->saddr) {
rth = ERR_PTR(-EINVAL);
if (ipv4_is_multicast(oldflp4->saddr) ||
ipv4_is_lbcast(oldflp4->saddr) ||
ipv4_is_zeronet(oldflp4->saddr))
if (ipv4_is_multicast(fl4->saddr) ||
ipv4_is_lbcast(fl4->saddr) ||
ipv4_is_zeronet(fl4->saddr))
goto out;

/* I removed check for oif == dev_out->oif here.
Expand All @@ -2497,11 +2498,11 @@ static struct rtable *ip_route_output_slow(struct net *net,
of another iface. --ANK
*/

if (oldflp4->flowi4_oif == 0 &&
(ipv4_is_multicast(oldflp4->daddr) ||
ipv4_is_lbcast(oldflp4->daddr))) {
if (fl4->flowi4_oif == 0 &&
(ipv4_is_multicast(fl4->daddr) ||
ipv4_is_lbcast(fl4->daddr))) {
/* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
dev_out = __ip_dev_find(net, oldflp4->saddr, false);
dev_out = __ip_dev_find(net, fl4->saddr, false);
if (dev_out == NULL)
goto out;

Expand All @@ -2520,20 +2521,20 @@ static struct rtable *ip_route_output_slow(struct net *net,
Luckily, this hack is good workaround.
*/

fl4.flowi4_oif = dev_out->ifindex;
fl4->flowi4_oif = dev_out->ifindex;
goto make_route;
}

if (!(oldflp4->flowi4_flags & FLOWI_FLAG_ANYSRC)) {
if (!(fl4->flowi4_flags & FLOWI_FLAG_ANYSRC)) {
/* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
if (!__ip_dev_find(net, oldflp4->saddr, false))
if (!__ip_dev_find(net, fl4->saddr, false))
goto out;
}
}


if (oldflp4->flowi4_oif) {
dev_out = dev_get_by_index_rcu(net, oldflp4->flowi4_oif);
if (fl4->flowi4_oif) {
dev_out = dev_get_by_index_rcu(net, fl4->flowi4_oif);
rth = ERR_PTR(-ENODEV);
if (dev_out == NULL)
goto out;
Expand All @@ -2543,37 +2544,37 @@ static struct rtable *ip_route_output_slow(struct net *net,
rth = ERR_PTR(-ENETUNREACH);
goto out;
}
if (ipv4_is_local_multicast(oldflp4->daddr) ||
ipv4_is_lbcast(oldflp4->daddr)) {
if (!fl4.saddr)
fl4.saddr = inet_select_addr(dev_out, 0,
RT_SCOPE_LINK);
if (ipv4_is_local_multicast(fl4->daddr) ||
ipv4_is_lbcast(fl4->daddr)) {
if (!fl4->saddr)
fl4->saddr = inet_select_addr(dev_out, 0,
RT_SCOPE_LINK);
goto make_route;
}
if (!fl4.saddr) {
if (ipv4_is_multicast(oldflp4->daddr))
fl4.saddr = inet_select_addr(dev_out, 0,
fl4.flowi4_scope);
else if (!oldflp4->daddr)
fl4.saddr = inet_select_addr(dev_out, 0,
RT_SCOPE_HOST);
if (fl4->saddr) {
if (ipv4_is_multicast(fl4->daddr))
fl4->saddr = inet_select_addr(dev_out, 0,
fl4->flowi4_scope);
else if (!fl4->daddr)
fl4->saddr = inet_select_addr(dev_out, 0,
RT_SCOPE_HOST);
}
}

if (!fl4.daddr) {
fl4.daddr = fl4.saddr;
if (!fl4.daddr)
fl4.daddr = fl4.saddr = htonl(INADDR_LOOPBACK);
if (!fl4->daddr) {
fl4->daddr = fl4->saddr;
if (!fl4->daddr)
fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK);
dev_out = net->loopback_dev;
fl4.flowi4_oif = net->loopback_dev->ifindex;
fl4->flowi4_oif = net->loopback_dev->ifindex;
res.type = RTN_LOCAL;
flags |= RTCF_LOCAL;
goto make_route;
}

if (fib_lookup(net, &fl4, &res)) {
if (fib_lookup(net, fl4, &res)) {
res.fi = NULL;
if (oldflp4->flowi4_oif) {
if (fl4->flowi4_oif) {
/* Apparently, routing tables are wrong. Assume,
that the destination is on link.
Expand All @@ -2592,9 +2593,9 @@ static struct rtable *ip_route_output_slow(struct net *net,
likely IPv6, but we do not.
*/

if (fl4.saddr == 0)
fl4.saddr = inet_select_addr(dev_out, 0,
RT_SCOPE_LINK);
if (fl4->saddr == 0)
fl4->saddr = inet_select_addr(dev_out, 0,
RT_SCOPE_LINK);
res.type = RTN_UNICAST;
goto make_route;
}
Expand All @@ -2603,52 +2604,53 @@ static struct rtable *ip_route_output_slow(struct net *net,
}

if (res.type == RTN_LOCAL) {
if (!fl4.saddr) {
if (!fl4->saddr) {
if (res.fi->fib_prefsrc)
fl4.saddr = res.fi->fib_prefsrc;
fl4->saddr = res.fi->fib_prefsrc;
else
fl4.saddr = fl4.daddr;
fl4->saddr = fl4->daddr;
}
dev_out = net->loopback_dev;
fl4.flowi4_oif = dev_out->ifindex;
fl4->flowi4_oif = dev_out->ifindex;
res.fi = NULL;
flags |= RTCF_LOCAL;
goto make_route;
}

#ifdef CONFIG_IP_ROUTE_MULTIPATH
if (res.fi->fib_nhs > 1 && fl4.flowi4_oif == 0)
if (res.fi->fib_nhs > 1 && fl4->flowi4_oif == 0)
fib_select_multipath(&res);
else
#endif
if (!res.prefixlen &&
res.table->tb_num_default > 1 &&
res.type == RTN_UNICAST && !fl4.flowi4_oif)
res.type == RTN_UNICAST && !fl4->flowi4_oif)
fib_select_default(&res);

if (!fl4.saddr)
fl4.saddr = FIB_RES_PREFSRC(net, res);
if (!fl4->saddr)
fl4->saddr = FIB_RES_PREFSRC(net, res);

dev_out = FIB_RES_DEV(res);
fl4.flowi4_oif = dev_out->ifindex;
fl4->flowi4_oif = dev_out->ifindex;


make_route:
rth = __mkroute_output(&res, &fl4, oldflp4, dev_out, flags);
rth = __mkroute_output(&res, fl4, orig_daddr, orig_saddr, orig_oif,
dev_out, flags);
if (!IS_ERR(rth)) {
unsigned int hash;

hash = rt_hash(oldflp4->daddr, oldflp4->saddr, oldflp4->flowi4_oif,
hash = rt_hash(orig_daddr, orig_saddr, orig_oif,
rt_genid(dev_net(dev_out)));
rth = rt_intern_hash(hash, rth, NULL, oldflp4->flowi4_oif);
rth = rt_intern_hash(hash, rth, NULL, orig_oif);
}

out:
rcu_read_unlock();
return rth;
}

struct rtable *__ip_route_output_key(struct net *net, const struct flowi4 *flp4)
struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *flp4)
{
struct rtable *rth;
unsigned int hash;
Expand Down

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