@@ -70,6 +70,7 @@ struct nh_grp_entry {
};
struct nh_group {
+ struct nh_group *spare; /* spare group for removals */
u16 num_nh;
bool mpath;
bool has_v4;
@@ -64,9 +64,16 @@ static void nexthop_free_mpath(struct ne
int i;
nhg = rcu_dereference_raw(nh->nh_grp);
- for (i = 0; i < nhg->num_nh; ++i)
- WARN_ON(nhg->nh_entries[i].nh);
+ for (i = 0; i < nhg->num_nh; ++i) {
+ struct nh_grp_entry *nhge = &nhg->nh_entries[i];
+ WARN_ON(!list_empty(&nhge->nh_list));
+ nexthop_put(nhge->nh);
+ }
+
+ WARN_ON(nhg->spare == nhg);
+
+ kfree(nhg->spare);
kfree(nhg);
}
@@ -698,46 +705,53 @@ static void nh_group_rebalance(struct nh
static void remove_nh_grp_entry(struct net *net, struct nh_grp_entry *nhge,
struct nl_info *nlinfo)
{
+ struct nh_grp_entry *nhges, *new_nhges;
struct nexthop *nhp = nhge->nh_parent;
struct nexthop *nh = nhge->nh;
- struct nh_grp_entry *nhges;
- struct nh_group *nhg;
- bool found = false;
- int i;
+ struct nh_group *nhg, *newg;
+ int i, j;
WARN_ON(!nh);
- list_del(&nhge->nh_list);
-
nhg = rtnl_dereference(nhp->nh_grp);
- nhges = nhg->nh_entries;
- for (i = 0; i < nhg->num_nh; ++i) {
- if (found) {
- nhges[i-1].nh = nhges[i].nh;
- nhges[i-1].weight = nhges[i].weight;
- list_del(&nhges[i].nh_list);
- list_add(&nhges[i-1].nh_list, &nhges[i-1].nh->grp_list);
- } else if (nhg->nh_entries[i].nh == nh) {
- found = true;
- }
- }
+ newg = nhg->spare;
- if (WARN_ON(!found))
+ /* last entry, keep it visible and remove the parent */
+ if (nhg->num_nh == 1) {
+ remove_nexthop(net, nhp, nlinfo);
return;
+ }
- nhg->num_nh--;
- nhg->nh_entries[nhg->num_nh].nh = NULL;
+ newg->has_v4 = nhg->has_v4;
+ newg->mpath = nhg->mpath;
+ newg->num_nh = nhg->num_nh;
- nh_group_rebalance(nhg);
+ /* copy old entries to new except the one getting removed */
+ nhges = nhg->nh_entries;
+ new_nhges = newg->nh_entries;
+ for (i = 0, j = 0; i < nhg->num_nh; ++i) {
+ /* current nexthop getting removed */
+ if (nhg->nh_entries[i].nh == nh) {
+ newg->num_nh--;
+ continue;
+ }
- nexthop_put(nh);
+ list_del(&nhges[i].nh_list);
+ new_nhges[j].nh_parent = nhges[i].nh_parent;
+ new_nhges[j].nh = nhges[i].nh;
+ new_nhges[j].weight = nhges[i].weight;
+ list_add(&new_nhges[j].nh_list, &new_nhges[j].nh->grp_list);
+ j++;
+ }
+
+ nh_group_rebalance(newg);
+ rcu_assign_pointer(nhp->nh_grp, newg);
+
+ list_del(&nhge->nh_list);
+ nexthop_put(nhge->nh);
if (nlinfo)
nexthop_notify(RTM_NEWNEXTHOP, nhp, nlinfo);
-
- /* if this group has no more entries then remove it */
- if (!nhg->num_nh)
- remove_nexthop(net, nhp, nlinfo);
}
static void remove_nexthop_from_groups(struct net *net, struct nexthop *nh,
@@ -747,6 +761,9 @@ static void remove_nexthop_from_groups(s
list_for_each_entry_safe(nhge, tmp, &nh->grp_list, nh_list)
remove_nh_grp_entry(net, nhge, nlinfo);
+
+ /* make sure all see the newly published array before releasing rtnl */
+ synchronize_rcu();
}
static void remove_nexthop_group(struct nexthop *nh, struct nl_info *nlinfo)
@@ -760,10 +777,7 @@ static void remove_nexthop_group(struct
if (WARN_ON(!nhge->nh))
continue;
- list_del(&nhge->nh_list);
- nexthop_put(nhge->nh);
- nhge->nh = NULL;
- nhg->num_nh--;
+ list_del_init(&nhge->nh_list);
}
}
@@ -1086,6 +1100,7 @@ static struct nexthop *nexthop_create_gr
{
struct nlattr *grps_attr = cfg->nh_grp;
struct nexthop_grp *entry = nla_data(grps_attr);
+ u16 num_nh = nla_len(grps_attr) / sizeof(*entry);
struct nh_group *nhg;
struct nexthop *nh;
int i;
@@ -1096,12 +1111,21 @@ static struct nexthop *nexthop_create_gr
nh->is_group = 1;
- nhg = nexthop_grp_alloc(nla_len(grps_attr) / sizeof(*entry));
+ nhg = nexthop_grp_alloc(num_nh);
if (!nhg) {
kfree(nh);
return ERR_PTR(-ENOMEM);
}
+ /* spare group used for removals */
+ nhg->spare = nexthop_grp_alloc(num_nh);
+ if (!nhg) {
+ kfree(nhg);
+ kfree(nh);
+ return NULL;
+ }
+ nhg->spare->spare = nhg;
+
for (i = 0; i < nhg->num_nh; ++i) {
struct nexthop *nhe;
struct nh_info *nhi;
@@ -1133,6 +1157,7 @@ out_no_nh:
for (; i >= 0; --i)
nexthop_put(nhg->nh_entries[i].nh);
+ kfree(nhg->spare);
kfree(nhg);
kfree(nh);