summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--include/net/dst.h114
-rw-r--r--include/net/dst_ops.h1
-rw-r--r--include/net/route.h2
-rw-r--r--net/core/dst.c39
-rw-r--r--net/decnet/dn_route.c18
-rw-r--r--net/ipv4/route.c45
-rw-r--r--net/ipv4/xfrm4_policy.c4
-rw-r--r--net/ipv6/route.c15
-rw-r--r--net/ipv6/xfrm6_policy.c2
9 files changed, 194 insertions, 46 deletions
diff --git a/include/net/dst.h b/include/net/dst.h
index be5a0d4c491d..94a8c234ea2a 100644
--- a/include/net/dst.h
+++ b/include/net/dst.h
@@ -40,24 +40,10 @@ struct dst_entry {
struct rcu_head rcu_head;
struct dst_entry *child;
struct net_device *dev;
- short error;
- short obsolete;
- int flags;
-#define DST_HOST 0x0001
-#define DST_NOXFRM 0x0002
-#define DST_NOPOLICY 0x0004
-#define DST_NOHASH 0x0008
-#define DST_NOCACHE 0x0010
+ struct dst_ops *ops;
+ unsigned long _metrics;
unsigned long expires;
-
- unsigned short header_len; /* more space at head required */
- unsigned short trailer_len; /* space to reserve at tail */
-
- unsigned int rate_tokens;
- unsigned long rate_last; /* rate limiting for ICMP */
-
struct dst_entry *path;
-
struct neighbour *neighbour;
struct hh_cache *hh;
#ifdef CONFIG_XFRM
@@ -68,17 +54,16 @@ struct dst_entry {
int (*input)(struct sk_buff*);
int (*output)(struct sk_buff*);
- struct dst_ops *ops;
-
- u32 _metrics[RTAX_MAX];
-
+ short error;
+ short obsolete;
+ unsigned short header_len; /* more space at head required */
+ unsigned short trailer_len; /* space to reserve at tail */
#ifdef CONFIG_IP_ROUTE_CLASSID
__u32 tclassid;
#else
__u32 __pad2;
#endif
-
/*
* Align __refcnt to a 64 bytes alignment
* (L1_CACHE_SIZE would be too much)
@@ -93,6 +78,14 @@ struct dst_entry {
atomic_t __refcnt; /* client references */
int __use;
unsigned long lastuse;
+ unsigned long rate_last; /* rate limiting for ICMP */
+ unsigned int rate_tokens;
+ int flags;
+#define DST_HOST 0x0001
+#define DST_NOXFRM 0x0002
+#define DST_NOPOLICY 0x0004
+#define DST_NOHASH 0x0008
+#define DST_NOCACHE 0x0010
union {
struct dst_entry *next;
struct rtable __rcu *rt_next;
@@ -103,10 +96,69 @@ struct dst_entry {
#ifdef __KERNEL__
+extern u32 *dst_cow_metrics_generic(struct dst_entry *dst, unsigned long old);
+
+#define DST_METRICS_READ_ONLY 0x1UL
+#define __DST_METRICS_PTR(Y) \
+ ((u32 *)((Y) & ~DST_METRICS_READ_ONLY))
+#define DST_METRICS_PTR(X) __DST_METRICS_PTR((X)->_metrics)
+
+static inline bool dst_metrics_read_only(const struct dst_entry *dst)
+{
+ return dst->_metrics & DST_METRICS_READ_ONLY;
+}
+
+extern void __dst_destroy_metrics_generic(struct dst_entry *dst, unsigned long old);
+
+static inline void dst_destroy_metrics_generic(struct dst_entry *dst)
+{
+ unsigned long val = dst->_metrics;
+ if (!(val & DST_METRICS_READ_ONLY))
+ __dst_destroy_metrics_generic(dst, val);
+}
+
+static inline u32 *dst_metrics_write_ptr(struct dst_entry *dst)
+{
+ unsigned long p = dst->_metrics;
+
+ if (p & DST_METRICS_READ_ONLY)
+ return dst->ops->cow_metrics(dst, p);
+ return __DST_METRICS_PTR(p);
+}
+
+/* This may only be invoked before the entry has reached global
+ * visibility.
+ */
+static inline void dst_init_metrics(struct dst_entry *dst,
+ const u32 *src_metrics,
+ bool read_only)
+{
+ dst->_metrics = ((unsigned long) src_metrics) |
+ (read_only ? DST_METRICS_READ_ONLY : 0);
+}
+
+static inline void dst_copy_metrics(struct dst_entry *dest, const struct dst_entry *src)
+{
+ u32 *dst_metrics = dst_metrics_write_ptr(dest);
+
+ if (dst_metrics) {
+ u32 *src_metrics = DST_METRICS_PTR(src);
+
+ memcpy(dst_metrics, src_metrics, RTAX_MAX * sizeof(u32));
+ }
+}
+
+static inline u32 *dst_metrics_ptr(struct dst_entry *dst)
+{
+ return DST_METRICS_PTR(dst);
+}
+
static inline u32
dst_metric_raw(const struct dst_entry *dst, const int metric)
{
- return dst->_metrics[metric-1];
+ u32 *p = DST_METRICS_PTR(dst);
+
+ return p[metric-1];
}
static inline u32
@@ -131,22 +183,10 @@ dst_metric_advmss(const struct dst_entry *dst)
static inline void dst_metric_set(struct dst_entry *dst, int metric, u32 val)
{
- dst->_metrics[metric-1] = val;
-}
-
-static inline void dst_import_metrics(struct dst_entry *dst, const u32 *src_metrics)
-{
- memcpy(dst->_metrics, src_metrics, RTAX_MAX * sizeof(u32));
-}
+ u32 *p = dst_metrics_write_ptr(dst);
-static inline void dst_copy_metrics(struct dst_entry *dest, const struct dst_entry *src)
-{
- dst_import_metrics(dest, src->_metrics);
-}
-
-static inline u32 *dst_metrics_ptr(struct dst_entry *dst)
-{
- return dst->_metrics;
+ if (p)
+ p[metric-1] = val;
}
static inline u32
diff --git a/include/net/dst_ops.h b/include/net/dst_ops.h
index 21a320b8708e..dc0746328947 100644
--- a/include/net/dst_ops.h
+++ b/include/net/dst_ops.h
@@ -18,6 +18,7 @@ struct dst_ops {
struct dst_entry * (*check)(struct dst_entry *, __u32 cookie);
unsigned int (*default_advmss)(const struct dst_entry *);
unsigned int (*default_mtu)(const struct dst_entry *);
+ u32 * (*cow_metrics)(struct dst_entry *, unsigned long);
void (*destroy)(struct dst_entry *);
void (*ifdown)(struct dst_entry *,
struct net_device *dev, int how);
diff --git a/include/net/route.h b/include/net/route.h
index 93e10c453f6b..5677cbf0c6e6 100644
--- a/include/net/route.h
+++ b/include/net/route.h
@@ -49,6 +49,7 @@
struct fib_nh;
struct inet_peer;
+struct fib_info;
struct rtable {
struct dst_entry dst;
@@ -69,6 +70,7 @@ struct rtable {
/* Miscellaneous cached information */
__be32 rt_spec_dst; /* RFC1122 specific destination */
struct inet_peer *peer; /* long-living peer info */
+ struct fib_info *fi; /* for client ref to shared metrics */
};
static inline bool rt_is_input_route(struct rtable *rt)
diff --git a/net/core/dst.c b/net/core/dst.c
index b99c7c7ffce2..578893505702 100644
--- a/net/core/dst.c
+++ b/net/core/dst.c
@@ -164,6 +164,8 @@ int dst_discard(struct sk_buff *skb)
}
EXPORT_SYMBOL(dst_discard);
+static const u32 dst_default_metrics[RTAX_MAX];
+
void *dst_alloc(struct dst_ops *ops)
{
struct dst_entry *dst;
@@ -180,6 +182,7 @@ void *dst_alloc(struct dst_ops *ops)
dst->lastuse = jiffies;
dst->path = dst;
dst->input = dst->output = dst_discard;
+ dst_init_metrics(dst, dst_default_metrics, true);
#if RT_CACHE_DEBUG >= 2
atomic_inc(&dst_total);
#endif
@@ -282,6 +285,42 @@ void dst_release(struct dst_entry *dst)
}
EXPORT_SYMBOL(dst_release);
+u32 *dst_cow_metrics_generic(struct dst_entry *dst, unsigned long old)
+{
+ u32 *p = kmalloc(sizeof(u32) * RTAX_MAX, GFP_ATOMIC);
+
+ if (p) {
+ u32 *old_p = __DST_METRICS_PTR(old);
+ unsigned long prev, new;
+
+ memcpy(p, old_p, sizeof(u32) * RTAX_MAX);
+
+ new = (unsigned long) p;
+ prev = cmpxchg(&dst->_metrics, old, new);
+
+ if (prev != old) {
+ kfree(p);
+ p = __DST_METRICS_PTR(prev);
+ if (prev & DST_METRICS_READ_ONLY)
+ p = NULL;
+ }
+ }
+ return p;
+}
+EXPORT_SYMBOL(dst_cow_metrics_generic);
+
+/* Caller asserts that dst_metrics_read_only(dst) is false. */
+void __dst_destroy_metrics_generic(struct dst_entry *dst, unsigned long old)
+{
+ unsigned long prev, new;
+
+ new = (unsigned long) dst_default_metrics;
+ prev = cmpxchg(&dst->_metrics, old, new);
+ if (prev == old)
+ kfree(__DST_METRICS_PTR(old));
+}
+EXPORT_SYMBOL(__dst_destroy_metrics_generic);
+
/**
* skb_dst_set_noref - sets skb dst, without a reference
* @skb: buffer
diff --git a/net/decnet/dn_route.c b/net/decnet/dn_route.c
index 5e636365d33c..42c9c62d3417 100644
--- a/net/decnet/dn_route.c
+++ b/net/decnet/dn_route.c
@@ -112,6 +112,7 @@ static int dn_dst_gc(struct dst_ops *ops);
static struct dst_entry *dn_dst_check(struct dst_entry *, __u32);
static unsigned int dn_dst_default_advmss(const struct dst_entry *dst);
static unsigned int dn_dst_default_mtu(const struct dst_entry *dst);
+static void dn_dst_destroy(struct dst_entry *);
static struct dst_entry *dn_dst_negative_advice(struct dst_entry *);
static void dn_dst_link_failure(struct sk_buff *);
static void dn_dst_update_pmtu(struct dst_entry *dst, u32 mtu);
@@ -133,11 +134,18 @@ static struct dst_ops dn_dst_ops = {
.check = dn_dst_check,
.default_advmss = dn_dst_default_advmss,
.default_mtu = dn_dst_default_mtu,
+ .cow_metrics = dst_cow_metrics_generic,
+ .destroy = dn_dst_destroy,
.negative_advice = dn_dst_negative_advice,
.link_failure = dn_dst_link_failure,
.update_pmtu = dn_dst_update_pmtu,
};
+static void dn_dst_destroy(struct dst_entry *dst)
+{
+ dst_destroy_metrics_generic(dst);
+}
+
static __inline__ unsigned dn_hash(__le16 src, __le16 dst)
{
__u16 tmp = (__u16 __force)(src ^ dst);
@@ -814,14 +822,14 @@ static int dn_rt_set_next_hop(struct dn_route *rt, struct dn_fib_res *res)
{
struct dn_fib_info *fi = res->fi;
struct net_device *dev = rt->dst.dev;
+ unsigned int mss_metric;
struct neighbour *n;
- unsigned int metric;
if (fi) {
if (DN_FIB_RES_GW(*res) &&
DN_FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
rt->rt_gateway = DN_FIB_RES_GW(*res);
- dst_import_metrics(&rt->dst, fi->fib_metrics);
+ dst_init_metrics(&rt->dst, fi->fib_metrics, true);
}
rt->rt_type = res->type;
@@ -834,10 +842,10 @@ static int dn_rt_set_next_hop(struct dn_route *rt, struct dn_fib_res *res)
if (dst_metric(&rt->dst, RTAX_MTU) > rt->dst.dev->mtu)
dst_metric_set(&rt->dst, RTAX_MTU, rt->dst.dev->mtu);
- metric = dst_metric_raw(&rt->dst, RTAX_ADVMSS);
- if (metric) {
+ mss_metric = dst_metric_raw(&rt->dst, RTAX_ADVMSS);
+ if (mss_metric) {
unsigned int mss = dn_mss_from_pmtu(dev, dst_mtu(&rt->dst));
- if (metric > mss)
+ if (mss_metric > mss)
dst_metric_set(&rt->dst, RTAX_ADVMSS, mss);
}
return 0;
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 3e5b7cc2db4f..980030d4e4ae 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -152,6 +152,36 @@ static void ipv4_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
{
}
+static u32 *ipv4_cow_metrics(struct dst_entry *dst, unsigned long old)
+{
+ u32 *p = kmalloc(sizeof(u32) * RTAX_MAX, GFP_ATOMIC);
+
+ if (p) {
+ u32 *old_p = __DST_METRICS_PTR(old);
+ unsigned long prev, new;
+
+ memcpy(p, old_p, sizeof(u32) * RTAX_MAX);
+
+ new = (unsigned long) p;
+ prev = cmpxchg(&dst->_metrics, old, new);
+
+ if (prev != old) {
+ kfree(p);
+ p = __DST_METRICS_PTR(prev);
+ if (prev & DST_METRICS_READ_ONLY)
+ p = NULL;
+ } else {
+ struct rtable *rt = (struct rtable *) dst;
+
+ if (rt->fi) {
+ fib_info_put(rt->fi);
+ rt->fi = NULL;
+ }
+ }
+ }
+ return p;
+}
+
static struct dst_ops ipv4_dst_ops = {
.family = AF_INET,
.protocol = cpu_to_be16(ETH_P_IP),
@@ -159,6 +189,7 @@ static struct dst_ops ipv4_dst_ops = {
.check = ipv4_dst_check,
.default_advmss = ipv4_default_advmss,
.default_mtu = ipv4_default_mtu,
+ .cow_metrics = ipv4_cow_metrics,
.destroy = ipv4_dst_destroy,
.ifdown = ipv4_dst_ifdown,
.negative_advice = ipv4_negative_advice,
@@ -1441,6 +1472,8 @@ void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw,
if (rt->peer)
atomic_inc(&rt->peer->refcnt);
+ if (rt->fi)
+ atomic_inc(&rt->fi->fib_clntref);
if (arp_bind_neighbour(&rt->dst) ||
!(rt->dst.neighbour->nud_state &
@@ -1720,6 +1753,11 @@ static void ipv4_dst_destroy(struct dst_entry *dst)
struct rtable *rt = (struct rtable *) dst;
struct inet_peer *peer = rt->peer;
+ dst_destroy_metrics_generic(dst);
+ if (rt->fi) {
+ fib_info_put(rt->fi);
+ rt->fi = NULL;
+ }
if (peer) {
rt->peer = NULL;
inet_putpeer(peer);
@@ -1824,7 +1862,9 @@ static void rt_set_nexthop(struct rtable *rt, struct fib_result *res, u32 itag)
if (FIB_RES_GW(*res) &&
FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
rt->rt_gateway = FIB_RES_GW(*res);
- dst_import_metrics(dst, fi->fib_metrics);
+ rt->fi = fi;
+ atomic_inc(&fi->fib_clntref);
+ dst_init_metrics(dst, fi->fib_metrics, true);
#ifdef CONFIG_IP_ROUTE_CLASSID
dst->tclassid = FIB_RES_NH(*res).nh_tclassid;
#endif
@@ -2752,6 +2792,9 @@ static int ipv4_dst_blackhole(struct net *net, struct rtable **rp, struct flowi
rt->peer = ort->peer;
if (rt->peer)
atomic_inc(&rt->peer->refcnt);
+ rt->fi = ort->fi;
+ if (rt->fi)
+ atomic_inc(&rt->fi->fib_clntref);
dst_free(new);
}
diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c
index b057d40addec..19fbdec6baaa 100644
--- a/net/ipv4/xfrm4_policy.c
+++ b/net/ipv4/xfrm4_policy.c
@@ -196,8 +196,11 @@ static void xfrm4_dst_destroy(struct dst_entry *dst)
{
struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
+ dst_destroy_metrics_generic(dst);
+
if (likely(xdst->u.rt.peer))
inet_putpeer(xdst->u.rt.peer);
+
xfrm_dst_destroy(xdst);
}
@@ -215,6 +218,7 @@ static struct dst_ops xfrm4_dst_ops = {
.protocol = cpu_to_be16(ETH_P_IP),
.gc = xfrm4_garbage_collect,
.update_pmtu = xfrm4_update_pmtu,
+ .cow_metrics = dst_cow_metrics_generic,
.destroy = xfrm4_dst_destroy,
.ifdown = xfrm4_dst_ifdown,
.local_out = __ip_local_out,
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 1534508f6c68..45fafa018f12 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -105,6 +105,7 @@ static struct dst_ops ip6_dst_ops_template = {
.check = ip6_dst_check,
.default_advmss = ip6_default_advmss,
.default_mtu = ip6_default_mtu,
+ .cow_metrics = dst_cow_metrics_generic,
.destroy = ip6_dst_destroy,
.ifdown = ip6_dst_ifdown,
.negative_advice = ip6_negative_advice,
@@ -125,6 +126,10 @@ static struct dst_ops ip6_dst_blackhole_ops = {
.update_pmtu = ip6_rt_blackhole_update_pmtu,
};
+static const u32 ip6_template_metrics[RTAX_MAX] = {
+ [RTAX_HOPLIMIT - 1] = 255,
+};
+
static struct rt6_info ip6_null_entry_template = {
.dst = {
.__refcnt = ATOMIC_INIT(1),
@@ -193,6 +198,7 @@ static void ip6_dst_destroy(struct dst_entry *dst)
rt->rt6i_idev = NULL;
in6_dev_put(idev);
}
+ dst_destroy_metrics_generic(dst);
if (peer) {
BUG_ON(!(rt->rt6i_flags & RTF_CACHE));
rt->rt6i_peer = NULL;
@@ -2681,7 +2687,8 @@ static int __net_init ip6_route_net_init(struct net *net)
net->ipv6.ip6_null_entry->dst.path =
(struct dst_entry *)net->ipv6.ip6_null_entry;
net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
- dst_metric_set(&net->ipv6.ip6_null_entry->dst, RTAX_HOPLIMIT, 255);
+ dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
+ ip6_template_metrics, true);
#ifdef CONFIG_IPV6_MULTIPLE_TABLES
net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
@@ -2692,7 +2699,8 @@ static int __net_init ip6_route_net_init(struct net *net)
net->ipv6.ip6_prohibit_entry->dst.path =
(struct dst_entry *)net->ipv6.ip6_prohibit_entry;
net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
- dst_metric_set(&net->ipv6.ip6_prohibit_entry->dst, RTAX_HOPLIMIT, 255);
+ dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
+ ip6_template_metrics, true);
net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
sizeof(*net->ipv6.ip6_blk_hole_entry),
@@ -2702,7 +2710,8 @@ static int __net_init ip6_route_net_init(struct net *net)
net->ipv6.ip6_blk_hole_entry->dst.path =
(struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
- dst_metric_set(&net->ipv6.ip6_blk_hole_entry->dst, RTAX_HOPLIMIT, 255);
+ dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
+ ip6_template_metrics, true);
#endif
net->ipv6.sysctl.flush_delay = 0;
diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c
index da87428681cc..834dc02f1d4f 100644
--- a/net/ipv6/xfrm6_policy.c
+++ b/net/ipv6/xfrm6_policy.c
@@ -220,6 +220,7 @@ static void xfrm6_dst_destroy(struct dst_entry *dst)
if (likely(xdst->u.rt6.rt6i_idev))
in6_dev_put(xdst->u.rt6.rt6i_idev);
+ dst_destroy_metrics_generic(dst);
if (likely(xdst->u.rt6.rt6i_peer))
inet_putpeer(xdst->u.rt6.rt6i_peer);
xfrm_dst_destroy(xdst);
@@ -257,6 +258,7 @@ static struct dst_ops xfrm6_dst_ops = {
.protocol = cpu_to_be16(ETH_P_IPV6),
.gc = xfrm6_garbage_collect,
.update_pmtu = xfrm6_update_pmtu,
+ .cow_metrics = dst_cow_metrics_generic,
.destroy = xfrm6_dst_destroy,
.ifdown = xfrm6_dst_ifdown,
.local_out = __ip6_local_out,