ipv4: Add fib_nh_common to fib_result

Most of the ipv4 code only needs data from fib_nh_common. Add
fib_nh_common selection to fib_result and update users to use it.

Right now, fib_nh_common in fib_result will point to a fib_nh struct
that is embedded within a fib_info:

        fib_info  --> fib_nh
                      fib_nh
                      ...
                      fib_nh
                        ^
    fib_result->nhc ----+

Later, nhc can point to a fib_nh within a nexthop struct:

        fib_info --> nexthop --> fib_nh
                                   ^
    fib_result->nhc ---------------+

or for a nexthop group:

        fib_info --> nexthop --> nexthop --> fib_nh
                                 nexthop --> fib_nh
                                 ...
                                 nexthop --> fib_nh
                                               ^
    fib_result->nhc ---------------------------+

In all cases nhsel within fib_result will point to which leg in the
multipath route is used.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David Ahern 2019-04-02 14:11:55 -07:00 committed by David S. Miller
parent 0af7e7c128
commit eba618abac
7 changed files with 99 additions and 65 deletions

View File

@ -156,15 +156,16 @@ struct fib_rule;
struct fib_table;
struct fib_result {
__be32 prefix;
unsigned char prefixlen;
unsigned char nh_sel;
unsigned char type;
unsigned char scope;
u32 tclassid;
struct fib_info *fi;
struct fib_table *table;
struct hlist_head *fa_head;
__be32 prefix;
unsigned char prefixlen;
unsigned char nh_sel;
unsigned char type;
unsigned char scope;
u32 tclassid;
struct fib_nh_common *nhc;
struct fib_info *fi;
struct fib_table *table;
struct hlist_head *fa_head;
};
struct fib_result_nl {
@ -182,11 +183,10 @@ struct fib_result_nl {
int err;
};
#ifdef CONFIG_IP_ROUTE_MULTIPATH
#define FIB_RES_NH(res) ((res).fi->fib_nh[(res).nh_sel])
#else /* CONFIG_IP_ROUTE_MULTIPATH */
#define FIB_RES_NH(res) ((res).fi->fib_nh[0])
#endif /* CONFIG_IP_ROUTE_MULTIPATH */
static inline struct fib_nh_common *fib_info_nhc(struct fib_info *fi, int nhsel)
{
return &fi->fib_nh[nhsel].nh_common;
}
#ifdef CONFIG_IP_MULTIPLE_TABLES
#define FIB_TABLE_HASHSZ 256
@ -195,18 +195,11 @@ struct fib_result_nl {
#endif
__be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh);
__be32 fib_result_prefsrc(struct net *net, struct fib_result *res);
#define FIB_RES_SADDR(net, res) \
((FIB_RES_NH(res).nh_saddr_genid == \
atomic_read(&(net)->ipv4.dev_addr_genid)) ? \
FIB_RES_NH(res).nh_saddr : \
fib_info_update_nh_saddr((net), &FIB_RES_NH(res)))
#define FIB_RES_GW(res) (FIB_RES_NH(res).fib_nh_gw4)
#define FIB_RES_DEV(res) (FIB_RES_NH(res).fib_nh_dev)
#define FIB_RES_OIF(res) (FIB_RES_NH(res).fib_nh_oif)
#define FIB_RES_PREFSRC(net, res) ((res).fi->fib_prefsrc ? : \
FIB_RES_SADDR(net, res))
#define FIB_RES_NHC(res) ((res).nhc)
#define FIB_RES_DEV(res) (FIB_RES_NHC(res)->nhc_dev)
#define FIB_RES_OIF(res) (FIB_RES_NHC(res)->nhc_oif)
struct fib_entry_notifier_info {
struct fib_notifier_info info; /* must be first */
@ -453,10 +446,12 @@ struct fib_table *fib_trie_table(u32 id, struct fib_table *alias);
static inline void fib_combine_itag(u32 *itag, const struct fib_result *res)
{
#ifdef CONFIG_IP_ROUTE_CLASSID
struct fib_nh_common *nhc = res->nhc;
struct fib_nh *nh = container_of(nhc, struct fib_nh, nh_common);
#ifdef CONFIG_IP_MULTIPLE_TABLES
u32 rtag;
#endif
*itag = FIB_RES_NH(*res).nh_tclassid<<16;
*itag = nh->nh_tclassid << 16;
#ifdef CONFIG_IP_MULTIPLE_TABLES
rtag = res->tclassid;
if (*itag == 0)

View File

@ -4555,11 +4555,11 @@ static int bpf_fib_set_fwd_params(struct bpf_fib_lookup *params,
static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
u32 flags, bool check_mtu)
{
struct fib_nh_common *nhc;
struct in_device *in_dev;
struct neighbour *neigh;
struct net_device *dev;
struct fib_result res;
struct fib_nh *nh;
struct flowi4 fl4;
int err;
u32 mtu;
@ -4632,15 +4632,15 @@ static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
return BPF_FIB_LKUP_RET_FRAG_NEEDED;
}
nh = &res.fi->fib_nh[res.nh_sel];
nhc = res.nhc;
/* do not handle lwt encaps right now */
if (nh->fib_nh_lws)
if (nhc->nhc_lwtstate)
return BPF_FIB_LKUP_RET_UNSUPP_LWT;
dev = nh->fib_nh_dev;
if (nh->fib_nh_gw4)
params->ipv4_dst = nh->fib_nh_gw4;
dev = nhc->nhc_dev;
if (nhc->nhc_has_gw)
params->ipv4_dst = nhc->nhc_gw.ipv4;
params->rt_metric = res.fi->fib_priority;

View File

@ -307,7 +307,7 @@ __be32 fib_compute_spec_dst(struct sk_buff *skb)
.flowi4_mark = vmark ? skb->mark : 0,
};
if (!fib_lookup(net, &fl4, &res, 0))
return FIB_RES_PREFSRC(net, res);
return fib_result_prefsrc(net, &res);
} else {
scope = RT_SCOPE_LINK;
}
@ -390,7 +390,7 @@ static int __fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
dev_match = fib_info_nh_uses_dev(res.fi, dev);
if (dev_match) {
ret = FIB_RES_NH(res).fib_nh_scope >= RT_SCOPE_HOST;
ret = FIB_RES_NHC(res)->nhc_scope >= RT_SCOPE_HOST;
return ret;
}
if (no_addr)
@ -402,7 +402,7 @@ static int __fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
ret = 0;
if (fib_lookup(net, &fl4, &res, FIB_LOOKUP_IGNORE_LINKSTATE) == 0) {
if (res.type == RTN_UNICAST)
ret = FIB_RES_NH(res).fib_nh_scope >= RT_SCOPE_HOST;
ret = FIB_RES_NHC(res)->nhc_scope >= RT_SCOPE_HOST;
}
return ret;

View File

@ -45,6 +45,7 @@ static inline void fib_result_assign(struct fib_result *res,
{
/* we used to play games with refcounts, but we now use RCU */
res->fi = fi;
res->nhc = fib_info_nhc(fi, 0);
}
struct fib_prop {

View File

@ -1075,6 +1075,21 @@ __be32 fib_info_update_nh_saddr(struct net *net, struct fib_nh *nh)
return nh->nh_saddr;
}
__be32 fib_result_prefsrc(struct net *net, struct fib_result *res)
{
struct fib_nh_common *nhc = res->nhc;
struct fib_nh *nh;
if (res->fi->fib_prefsrc)
return res->fi->fib_prefsrc;
nh = container_of(nhc, struct fib_nh, nh_common);
if (nh->nh_saddr_genid == atomic_read(&net->ipv4.dev_addr_genid))
return nh->nh_saddr;
return fib_info_update_nh_saddr(net, nh);
}
static bool fib_valid_prefsrc(struct fib_config *cfg, __be32 fib_prefsrc)
{
if (cfg->fc_type != RTN_LOCAL || !cfg->fc_dst ||
@ -1762,20 +1777,22 @@ void fib_select_multipath(struct fib_result *res, int hash)
struct net *net = fi->fib_net;
bool first = false;
for_nexthops(fi) {
change_nexthops(fi) {
if (net->ipv4.sysctl_fib_multipath_use_neigh) {
if (!fib_good_nh(nh))
if (!fib_good_nh(nexthop_nh))
continue;
if (!first) {
res->nh_sel = nhsel;
res->nhc = &nexthop_nh->nh_common;
first = true;
}
}
if (hash > atomic_read(&nh->fib_nh_upper_bound))
if (hash > atomic_read(&nexthop_nh->fib_nh_upper_bound))
continue;
res->nh_sel = nhsel;
res->nhc = &nexthop_nh->nh_common;
return;
} endfor_nexthops(fi);
}
@ -1802,5 +1819,5 @@ void fib_select_path(struct net *net, struct fib_result *res,
check_saddr:
if (!fl4->saddr)
fl4->saddr = FIB_RES_PREFSRC(net, *res);
fl4->saddr = fib_result_prefsrc(net, res);
}

View File

@ -1470,17 +1470,17 @@ found:
if (fi->fib_flags & RTNH_F_DEAD)
continue;
for (nhsel = 0; nhsel < fi->fib_nhs; nhsel++) {
const struct fib_nh *nh = &fi->fib_nh[nhsel];
struct fib_nh_common *nhc = fib_info_nhc(fi, nhsel);
if (nh->fib_nh_flags & RTNH_F_DEAD)
if (nhc->nhc_flags & RTNH_F_DEAD)
continue;
if (ip_ignore_linkdown(nh->fib_nh_dev) &&
nh->fib_nh_flags & RTNH_F_LINKDOWN &&
if (ip_ignore_linkdown(nhc->nhc_dev) &&
nhc->nhc_flags & RTNH_F_LINKDOWN &&
!(fib_flags & FIB_LOOKUP_IGNORE_LINKSTATE))
continue;
if (!(flp->flowi4_flags & FLOWI_FLAG_SKIP_NH_OIF)) {
if (flp->flowi4_oif &&
flp->flowi4_oif != nh->fib_nh_oif)
flp->flowi4_oif != nhc->nhc_oif)
continue;
}
@ -1490,6 +1490,7 @@ found:
res->prefix = htonl(n->key);
res->prefixlen = KEYLENGTH - fa->fa_slen;
res->nh_sel = nhsel;
res->nhc = nhc;
res->type = fa->fa_type;
res->scope = fi->fib_scope;
res->fi = fi;
@ -1498,7 +1499,7 @@ found:
#ifdef CONFIG_IP_FIB_TRIE_STATS
this_cpu_inc(stats->semantic_match_passed);
#endif
trace_fib_table_lookup(tb->tb_id, flp, &nh->nh_common, err);
trace_fib_table_lookup(tb->tb_id, flp, nhc, err);
return err;
}

View File

@ -778,8 +778,10 @@ static void __ip_do_redirect(struct rtable *rt, struct sk_buff *skb, struct flow
neigh_event_send(n, NULL);
} else {
if (fib_lookup(net, fl4, &res, 0) == 0) {
struct fib_nh *nh = &FIB_RES_NH(res);
struct fib_nh_common *nhc = FIB_RES_NHC(res);
struct fib_nh *nh;
nh = container_of(nhc, struct fib_nh, nh_common);
update_or_create_fnhe(nh, fl4->daddr, new_gw,
0, false,
jiffies + ip_rt_gc_timeout);
@ -1027,8 +1029,10 @@ static void __ip_rt_update_pmtu(struct rtable *rt, struct flowi4 *fl4, u32 mtu)
rcu_read_lock();
if (fib_lookup(dev_net(dst->dev), fl4, &res, 0) == 0) {
struct fib_nh *nh = &FIB_RES_NH(res);
struct fib_nh_common *nhc = FIB_RES_NHC(res);
struct fib_nh *nh;
nh = container_of(nhc, struct fib_nh, nh_common);
update_or_create_fnhe(nh, fl4->daddr, 0, mtu, lock,
jiffies + ip_rt_mtu_expires);
}
@ -1235,7 +1239,7 @@ void ip_rt_get_source(u8 *addr, struct sk_buff *skb, struct rtable *rt)
rcu_read_lock();
if (fib_lookup(dev_net(rt->dst.dev), &fl4, &res, 0) == 0)
src = FIB_RES_PREFSRC(dev_net(rt->dst.dev), res);
src = fib_result_prefsrc(dev_net(rt->dst.dev), &res);
else
src = inet_select_addr(rt->dst.dev,
rt_nexthop(rt, iph->daddr),
@ -1354,9 +1358,9 @@ static struct fib_nh_exception *find_exception(struct fib_nh *nh, __be32 daddr)
u32 ip_mtu_from_fib_result(struct fib_result *res, __be32 daddr)
{
struct fib_nh_common *nhc = res->nhc;
struct net_device *dev = nhc->nhc_dev;
struct fib_info *fi = res->fi;
struct fib_nh *nh = &fi->fib_nh[res->nh_sel];
struct net_device *dev = nh->fib_nh_dev;
u32 mtu = 0;
if (dev_net(dev)->ipv4.sysctl_ip_fwd_use_pmtu ||
@ -1364,6 +1368,7 @@ u32 ip_mtu_from_fib_result(struct fib_result *res, __be32 daddr)
mtu = fi->fib_mtu;
if (likely(!mtu)) {
struct fib_nh *nh = container_of(nhc, struct fib_nh, nh_common);
struct fib_nh_exception *fnhe;
fnhe = find_exception(nh, daddr);
@ -1374,7 +1379,7 @@ u32 ip_mtu_from_fib_result(struct fib_result *res, __be32 daddr)
if (likely(!mtu))
mtu = min(READ_ONCE(dev->mtu), IP_MAX_MTU);
return mtu - lwtunnel_headroom(nh->fib_nh_lws, mtu);
return mtu - lwtunnel_headroom(nhc->nhc_lwtstate, mtu);
}
static bool rt_bind_exception(struct rtable *rt, struct fib_nh_exception *fnhe,
@ -1529,7 +1534,8 @@ static void rt_set_nexthop(struct rtable *rt, __be32 daddr,
bool cached = false;
if (fi) {
struct fib_nh *nh = &FIB_RES_NH(*res);
struct fib_nh_common *nhc = FIB_RES_NHC(*res);
struct fib_nh *nh = container_of(nhc, struct fib_nh, nh_common);
if (nh->fib_nh_gw4 && nh->fib_nh_scope == RT_SCOPE_LINK) {
rt->rt_gateway = nh->fib_nh_gw4;
@ -1699,15 +1705,18 @@ static int __mkroute_input(struct sk_buff *skb,
struct in_device *in_dev,
__be32 daddr, __be32 saddr, u32 tos)
{
struct fib_nh_common *nhc = FIB_RES_NHC(*res);
struct net_device *dev = nhc->nhc_dev;
struct fib_nh_exception *fnhe;
struct rtable *rth;
struct fib_nh *nh;
int err;
struct in_device *out_dev;
bool do_cache;
u32 itag = 0;
/* get a working reference to the output device */
out_dev = __in_dev_get_rcu(FIB_RES_DEV(*res));
out_dev = __in_dev_get_rcu(dev);
if (!out_dev) {
net_crit_ratelimited("Bug in ip_route_input_slow(). Please report.\n");
return -EINVAL;
@ -1724,10 +1733,13 @@ static int __mkroute_input(struct sk_buff *skb,
do_cache = res->fi && !itag;
if (out_dev == in_dev && err && IN_DEV_TX_REDIRECTS(out_dev) &&
skb->protocol == htons(ETH_P_IP) &&
(IN_DEV_SHARED_MEDIA(out_dev) ||
inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res))))
IPCB(skb)->flags |= IPSKB_DOREDIRECT;
skb->protocol == htons(ETH_P_IP)) {
__be32 gw = nhc->nhc_family == AF_INET ? nhc->nhc_gw.ipv4 : 0;
if (IN_DEV_SHARED_MEDIA(out_dev) ||
inet_addr_onlink(out_dev, saddr, gw))
IPCB(skb)->flags |= IPSKB_DOREDIRECT;
}
if (skb->protocol != htons(ETH_P_IP)) {
/* Not IP (i.e. ARP). Do not create route, if it is
@ -1744,12 +1756,13 @@ static int __mkroute_input(struct sk_buff *skb,
}
}
fnhe = find_exception(&FIB_RES_NH(*res), daddr);
nh = container_of(nhc, struct fib_nh, nh_common);
fnhe = find_exception(nh, daddr);
if (do_cache) {
if (fnhe)
rth = rcu_dereference(fnhe->fnhe_rth_input);
else
rth = rcu_dereference(FIB_RES_NH(*res).nh_rth_input);
rth = rcu_dereference(nh->nh_rth_input);
if (rt_cache_valid(rth)) {
skb_dst_set_noref(skb, &rth->dst);
goto out;
@ -2043,7 +2056,11 @@ local_input:
do_cache = false;
if (res->fi) {
if (!itag) {
rth = rcu_dereference(FIB_RES_NH(*res).nh_rth_input);
struct fib_nh_common *nhc = FIB_RES_NHC(*res);
struct fib_nh *nh;
nh = container_of(nhc, struct fib_nh, nh_common);
rth = rcu_dereference(nh->nh_rth_input);
if (rt_cache_valid(rth)) {
skb_dst_set_noref(skb, &rth->dst);
err = 0;
@ -2073,15 +2090,17 @@ local_input:
}
if (do_cache) {
struct fib_nh *nh = &FIB_RES_NH(*res);
struct fib_nh_common *nhc = FIB_RES_NHC(*res);
struct fib_nh *nh;
rth->dst.lwtstate = lwtstate_get(nh->fib_nh_lws);
rth->dst.lwtstate = lwtstate_get(nhc->nhc_lwtstate);
if (lwtunnel_input_redirect(rth->dst.lwtstate)) {
WARN_ON(rth->dst.input == lwtunnel_input);
rth->dst.lwtstate->orig_input = rth->dst.input;
rth->dst.input = lwtunnel_input;
}
nh = container_of(nhc, struct fib_nh, nh_common);
if (unlikely(!rt_cache_route(nh, rth)))
rt_add_uncached_list(rth);
}
@ -2253,8 +2272,9 @@ static struct rtable *__mkroute_output(const struct fib_result *res,
fnhe = NULL;
do_cache &= fi != NULL;
if (fi) {
struct fib_nh_common *nhc = FIB_RES_NHC(*res);
struct fib_nh *nh = container_of(nhc, struct fib_nh, nh_common);
struct rtable __rcu **prth;
struct fib_nh *nh = &FIB_RES_NH(*res);
fnhe = find_exception(nh, fl4->daddr);
if (!do_cache)
@ -2264,8 +2284,8 @@ static struct rtable *__mkroute_output(const struct fib_result *res,
} else {
if (unlikely(fl4->flowi4_flags &
FLOWI_FLAG_KNOWN_NH &&
!(nh->fib_nh_gw4 &&
nh->fib_nh_scope == RT_SCOPE_LINK))) {
!(nhc->nhc_has_gw &&
nhc->nhc_scope == RT_SCOPE_LINK))) {
do_cache = false;
goto add;
}