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-rw-r--r--net/mpls/af_mpls.c37
-rw-r--r--net/mpls/internal.h45
2 files changed, 51 insertions, 31 deletions
diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c
index 665dec84f001..1863b94133e4 100644
--- a/net/mpls/af_mpls.c
+++ b/net/mpls/af_mpls.c
@@ -24,6 +24,8 @@
#include <net/nexthop.h>
#include "internal.h"
+#define MAX_NEW_LABELS 2
+
/* Maximum number of labels to look ahead at when selecting a path of
* a multipath route
*/
@@ -60,10 +62,7 @@ EXPORT_SYMBOL_GPL(mpls_output_possible);
static u8 *__mpls_nh_via(struct mpls_route *rt, struct mpls_nh *nh)
{
- u8 *nh0_via = PTR_ALIGN((u8 *)&rt->rt_nh[rt->rt_nhn], VIA_ALEN_ALIGN);
- int nh_index = nh - rt->rt_nh;
-
- return nh0_via + rt->rt_max_alen * nh_index;
+ return (u8 *)nh + rt->rt_via_offset;
}
static const u8 *mpls_nh_via(const struct mpls_route *rt,
@@ -189,6 +188,11 @@ static u32 mpls_multipath_hash(struct mpls_route *rt, struct sk_buff *skb)
return hash;
}
+static struct mpls_nh *mpls_get_nexthop(struct mpls_route *rt, u8 index)
+{
+ return (struct mpls_nh *)((u8 *)rt->rt_nh + index * rt->rt_nh_size);
+}
+
/* number of alive nexthops (rt->rt_nhn_alive) and the flags for
* a next hop (nh->nh_flags) are modified by netdev event handlers.
* Since those fields can change at any moment, use READ_ONCE to
@@ -206,7 +210,7 @@ static struct mpls_nh *mpls_select_multipath(struct mpls_route *rt,
* one path
*/
if (rt->rt_nhn == 1)
- goto out;
+ return rt->rt_nh;
alive = READ_ONCE(rt->rt_nhn_alive);
if (alive == 0)
@@ -227,7 +231,7 @@ static struct mpls_nh *mpls_select_multipath(struct mpls_route *rt,
} endfor_nexthops(rt);
out:
- return &rt->rt_nh[nh_index];
+ return mpls_get_nexthop(rt, nh_index);
}
static bool mpls_egress(struct net *net, struct mpls_route *rt,
@@ -466,19 +470,20 @@ struct mpls_route_config {
int rc_mp_len;
};
-static struct mpls_route *mpls_rt_alloc(u8 num_nh, u8 max_alen)
+/* all nexthops within a route have the same size based on max
+ * number of labels and max via length for a hop
+ */
+static struct mpls_route *mpls_rt_alloc(u8 num_nh, u8 max_alen, u8 max_labels)
{
- u8 max_alen_aligned = ALIGN(max_alen, VIA_ALEN_ALIGN);
+ u8 nh_size = MPLS_NH_SIZE(max_labels, max_alen);
struct mpls_route *rt;
- rt = kzalloc(ALIGN(sizeof(*rt) + num_nh * sizeof(*rt->rt_nh),
- VIA_ALEN_ALIGN) +
- num_nh * max_alen_aligned,
- GFP_KERNEL);
+ rt = kzalloc(sizeof(*rt) + num_nh * nh_size, GFP_KERNEL);
if (rt) {
rt->rt_nhn = num_nh;
rt->rt_nhn_alive = num_nh;
- rt->rt_max_alen = max_alen_aligned;
+ rt->rt_nh_size = nh_size;
+ rt->rt_via_offset = MPLS_NH_VIA_OFF(max_labels);
}
return rt;
@@ -892,7 +897,7 @@ static int mpls_route_add(struct mpls_route_config *cfg)
goto errout;
err = -ENOMEM;
- rt = mpls_rt_alloc(nhs, max_via_alen);
+ rt = mpls_rt_alloc(nhs, max_via_alen, MAX_NEW_LABELS);
if (!rt)
goto errout;
@@ -1964,7 +1969,7 @@ static int resize_platform_label_table(struct net *net, size_t limit)
/* In case the predefined labels need to be populated */
if (limit > MPLS_LABEL_IPV4NULL) {
struct net_device *lo = net->loopback_dev;
- rt0 = mpls_rt_alloc(1, lo->addr_len);
+ rt0 = mpls_rt_alloc(1, lo->addr_len, MAX_NEW_LABELS);
if (!rt0)
goto nort0;
RCU_INIT_POINTER(rt0->rt_nh->nh_dev, lo);
@@ -1978,7 +1983,7 @@ static int resize_platform_label_table(struct net *net, size_t limit)
}
if (limit > MPLS_LABEL_IPV6NULL) {
struct net_device *lo = net->loopback_dev;
- rt2 = mpls_rt_alloc(1, lo->addr_len);
+ rt2 = mpls_rt_alloc(1, lo->addr_len, MAX_NEW_LABELS);
if (!rt2)
goto nort2;
RCU_INIT_POINTER(rt2->rt_nh->nh_dev, lo);
diff --git a/net/mpls/internal.h b/net/mpls/internal.h
index 2ac97433c3b7..cc324c022049 100644
--- a/net/mpls/internal.h
+++ b/net/mpls/internal.h
@@ -64,7 +64,6 @@ struct mpls_dev {
struct sk_buff;
#define LABEL_NOT_SPECIFIED (1 << 20)
-#define MAX_NEW_LABELS 2
/* This maximum ha length copied from the definition of struct neighbour */
#define VIA_ALEN_ALIGN sizeof(unsigned long)
@@ -88,12 +87,26 @@ struct mpls_nh { /* next hop label forwarding entry */
* modified handling netdev events with rtnl lock held
*/
unsigned int nh_flags;
- u32 nh_label[MAX_NEW_LABELS];
u8 nh_labels;
u8 nh_via_alen;
u8 nh_via_table;
+ u8 nh_reserved1;
+
+ u32 nh_label[0];
};
+/* offset of via from beginning of mpls_nh */
+#define MPLS_NH_VIA_OFF(num_labels) \
+ ALIGN(sizeof(struct mpls_nh) + (num_labels) * sizeof(u32), \
+ VIA_ALEN_ALIGN)
+
+/* all nexthops within a route have the same size based on the
+ * max number of labels and max via length across all nexthops
+ */
+#define MPLS_NH_SIZE(num_labels, max_via_alen) \
+ (MPLS_NH_VIA_OFF((num_labels)) + \
+ ALIGN((max_via_alen), VIA_ALEN_ALIGN))
+
enum mpls_ttl_propagation {
MPLS_TTL_PROP_DEFAULT,
MPLS_TTL_PROP_ENABLED,
@@ -108,16 +121,16 @@ enum mpls_ttl_propagation {
* +----------------------+
* | mpls_nh 0 |
* +----------------------+
- * | ... |
- * +----------------------+
- * | mpls_nh n-1 |
- * +----------------------+
- * | alignment padding |
+ * | alignment padding | 4 bytes for odd number of labels
* +----------------------+
* | via[rt_max_alen] 0 |
* +----------------------+
+ * | alignment padding | via's aligned on sizeof(unsigned long)
+ * +----------------------+
* | ... |
* +----------------------+
+ * | mpls_nh n-1 |
+ * +----------------------+
* | via[rt_max_alen] n-1 |
* +----------------------+
*/
@@ -128,26 +141,28 @@ struct mpls_route { /* next hop label forwarding entry */
u8 rt_max_alen;
u8 rt_ttl_propagate;
u8 rt_nhn;
-
/* rt_nhn_alive is accessed under RCU in the packet path; it
* is modified handling netdev events with rtnl lock held
*/
u8 rt_nhn_alive;
- u16 rt_reserved1;
+ u8 rt_nh_size;
+ u8 rt_via_offset;
+ u8 rt_reserved1;
struct mpls_nh rt_nh[0];
};
#define for_nexthops(rt) { \
- int nhsel; struct mpls_nh *nh; \
- for (nhsel = 0, nh = (rt)->rt_nh; \
+ int nhsel; struct mpls_nh *nh; u8 *__nh; \
+ for (nhsel = 0, nh = (rt)->rt_nh, __nh = (u8 *)((rt)->rt_nh); \
nhsel < (rt)->rt_nhn; \
- nh++, nhsel++)
+ __nh += rt->rt_nh_size, nh = (struct mpls_nh *)__nh, nhsel++)
#define change_nexthops(rt) { \
- int nhsel; struct mpls_nh *nh; \
- for (nhsel = 0, nh = (struct mpls_nh *)((rt)->rt_nh); \
+ int nhsel; struct mpls_nh *nh; u8 *__nh; \
+ for (nhsel = 0, nh = (struct mpls_nh *)((rt)->rt_nh), \
+ __nh = (u8 *)((rt)->rt_nh); \
nhsel < (rt)->rt_nhn; \
- nh++, nhsel++)
+ __nh += rt->rt_nh_size, nh = (struct mpls_nh *)__nh, nhsel++)
#define endfor_nexthops(rt) }
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