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Diffstat (limited to 'net/sched/act_api.c')
-rw-r--r--net/sched/act_api.c251
1 files changed, 163 insertions, 88 deletions
diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index c39252d61e..3e30d72604 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -816,6 +816,9 @@ EXPORT_SYMBOL(tcf_idr_cleanup);
* its reference and bind counters, and return 1. Otherwise insert temporary
* error pointer (to prevent concurrent users from inserting actions with same
* index) and return 0.
+ *
+ * May return -EAGAIN for binding actions in case of a parallel add/delete on
+ * the requested index.
*/
int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index,
@@ -824,43 +827,61 @@ int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index,
struct tcf_idrinfo *idrinfo = tn->idrinfo;
struct tc_action *p;
int ret;
+ u32 max;
-again:
- mutex_lock(&idrinfo->lock);
if (*index) {
+again:
+ rcu_read_lock();
p = idr_find(&idrinfo->action_idr, *index);
+
if (IS_ERR(p)) {
/* This means that another process allocated
* index but did not assign the pointer yet.
*/
- mutex_unlock(&idrinfo->lock);
+ rcu_read_unlock();
goto again;
}
- if (p) {
- refcount_inc(&p->tcfa_refcnt);
- if (bind)
- atomic_inc(&p->tcfa_bindcnt);
- *a = p;
- ret = 1;
- } else {
- *a = NULL;
- ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index,
- *index, GFP_KERNEL);
- if (!ret)
- idr_replace(&idrinfo->action_idr,
- ERR_PTR(-EBUSY), *index);
+ if (!p) {
+ /* Empty slot, try to allocate it */
+ max = *index;
+ rcu_read_unlock();
+ goto new;
+ }
+
+ if (!refcount_inc_not_zero(&p->tcfa_refcnt)) {
+ /* Action was deleted in parallel */
+ rcu_read_unlock();
+ return -EAGAIN;
}
+
+ if (bind)
+ atomic_inc(&p->tcfa_bindcnt);
+ *a = p;
+
+ rcu_read_unlock();
+
+ return 1;
} else {
+ /* Find a slot */
*index = 1;
- *a = NULL;
- ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index,
- UINT_MAX, GFP_KERNEL);
- if (!ret)
- idr_replace(&idrinfo->action_idr, ERR_PTR(-EBUSY),
- *index);
+ max = UINT_MAX;
}
+
+new:
+ *a = NULL;
+
+ mutex_lock(&idrinfo->lock);
+ ret = idr_alloc_u32(&idrinfo->action_idr, ERR_PTR(-EBUSY), index, max,
+ GFP_KERNEL);
mutex_unlock(&idrinfo->lock);
+
+ /* N binds raced for action allocation,
+ * retry for all the ones that failed.
+ */
+ if (ret == -ENOSPC && *index == max)
+ ret = -EAGAIN;
+
return ret;
}
EXPORT_SYMBOL(tcf_idr_check_alloc);
@@ -1098,7 +1119,8 @@ repeat:
}
} else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) {
if (unlikely(!rcu_access_pointer(a->goto_chain))) {
- tcf_set_drop_reason(res, SKB_DROP_REASON_TC_ERROR);
+ tcf_set_drop_reason(skb,
+ SKB_DROP_REASON_TC_CHAIN_NOTFOUND);
return TC_ACT_SHOT;
}
tcf_action_goto_chain_exec(a, res);
@@ -1118,8 +1140,7 @@ int tcf_action_destroy(struct tc_action *actions[], int bind)
struct tc_action *a;
int ret = 0, i;
- for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
- a = actions[i];
+ tcf_act_for_each_action(i, a, actions) {
actions[i] = NULL;
ops = a->ops;
ret = __tcf_idr_release(a, bind, true);
@@ -1136,18 +1157,29 @@ static int tcf_action_put(struct tc_action *p)
return __tcf_action_put(p, false);
}
-/* Put all actions in this array, skip those NULL's. */
static void tcf_action_put_many(struct tc_action *actions[])
{
+ struct tc_action *a;
+ int i;
+
+ tcf_act_for_each_action(i, a, actions) {
+ const struct tc_action_ops *ops = a->ops;
+ if (tcf_action_put(a))
+ module_put(ops->owner);
+ }
+}
+
+static void tca_put_bound_many(struct tc_action *actions[], int init_res[])
+{
+ struct tc_action *a;
int i;
- for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
- struct tc_action *a = actions[i];
- const struct tc_action_ops *ops;
+ tcf_act_for_each_action(i, a, actions) {
+ const struct tc_action_ops *ops = a->ops;
- if (!a)
+ if (init_res[i] == ACT_P_CREATED)
continue;
- ops = a->ops;
+
if (tcf_action_put(a))
module_put(ops->owner);
}
@@ -1211,8 +1243,7 @@ int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[],
int err = -EINVAL, i;
struct nlattr *nest;
- for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
- a = actions[i];
+ tcf_act_for_each_action(i, a, actions) {
nest = nla_nest_start_noflag(skb, i + 1);
if (nest == NULL)
goto nla_put_failure;
@@ -1274,30 +1305,29 @@ static const struct nla_policy tcf_action_policy[TCA_ACT_MAX + 1] = {
[TCA_ACT_HW_STATS] = NLA_POLICY_BITFIELD32(TCA_ACT_HW_STATS_ANY),
};
-void tcf_idr_insert_many(struct tc_action *actions[])
+void tcf_idr_insert_many(struct tc_action *actions[], int init_res[])
{
+ struct tc_action *a;
int i;
- for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
- struct tc_action *a = actions[i];
+ tcf_act_for_each_action(i, a, actions) {
struct tcf_idrinfo *idrinfo;
- if (!a)
+ if (init_res[i] == ACT_P_BOUND)
continue;
+
idrinfo = a->idrinfo;
mutex_lock(&idrinfo->lock);
- /* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc if
- * it is just created, otherwise this is just a nop.
- */
+ /* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
idr_replace(&idrinfo->action_idr, a, a->tcfa_index);
mutex_unlock(&idrinfo->lock);
}
}
-struct tc_action_ops *tc_action_load_ops(struct nlattr *nla, bool police,
- bool rtnl_held,
+struct tc_action_ops *tc_action_load_ops(struct nlattr *nla, u32 flags,
struct netlink_ext_ack *extack)
{
+ bool police = flags & TCA_ACT_FLAGS_POLICE;
struct nlattr *tb[TCA_ACT_MAX + 1];
struct tc_action_ops *a_o;
char act_name[IFNAMSIZ];
@@ -1329,6 +1359,8 @@ struct tc_action_ops *tc_action_load_ops(struct nlattr *nla, bool police,
a_o = tc_lookup_action_n(act_name);
if (a_o == NULL) {
#ifdef CONFIG_MODULES
+ bool rtnl_held = !(flags & TCA_ACT_FLAGS_NO_RTNL);
+
if (rtnl_held)
rtnl_unlock();
request_module("act_%s", act_name);
@@ -1445,9 +1477,7 @@ int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
struct tc_action_ops *a_o;
- a_o = tc_action_load_ops(tb[i], flags & TCA_ACT_FLAGS_POLICE,
- !(flags & TCA_ACT_FLAGS_NO_RTNL),
- extack);
+ a_o = tc_action_load_ops(tb[i], flags, extack);
if (IS_ERR(a_o)) {
err = PTR_ERR(a_o);
goto err_mod;
@@ -1488,7 +1518,7 @@ int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
/* We have to commit them all together, because if any error happened in
* between, we could not handle the failure gracefully.
*/
- tcf_idr_insert_many(actions);
+ tcf_idr_insert_many(actions, init_res);
*attr_size = tcf_action_full_attrs_size(sz);
err = i - 1;
@@ -1497,10 +1527,8 @@ int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
err:
tcf_action_destroy(actions, flags & TCA_ACT_FLAGS_BIND);
err_mod:
- for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
- if (ops[i])
- module_put(ops[i]->owner);
- }
+ for (i = 0; i < TCA_ACT_MAX_PRIO && ops[i]; i++)
+ module_put(ops[i]->owner);
return err;
}
@@ -1753,10 +1781,10 @@ err_out:
static int tcf_action_delete(struct net *net, struct tc_action *actions[])
{
+ struct tc_action *a;
int i;
- for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
- struct tc_action *a = actions[i];
+ tcf_act_for_each_action(i, a, actions) {
const struct tc_action_ops *ops = a->ops;
/* Actions can be deleted concurrently so we must save their
* type and id to search again after reference is released.
@@ -1768,7 +1796,7 @@ static int tcf_action_delete(struct net *net, struct tc_action *actions[])
if (tcf_action_put(a)) {
/* last reference, action was deleted concurrently */
module_put(ops->owner);
- } else {
+ } else {
int ret;
/* now do the delete */
@@ -1780,31 +1808,45 @@ static int tcf_action_delete(struct net *net, struct tc_action *actions[])
return 0;
}
-static int
-tcf_reoffload_del_notify(struct net *net, struct tc_action *action)
+static struct sk_buff *tcf_reoffload_del_notify_msg(struct net *net,
+ struct tc_action *action)
{
size_t attr_size = tcf_action_fill_size(action);
struct tc_action *actions[TCA_ACT_MAX_PRIO] = {
[0] = action,
};
- const struct tc_action_ops *ops = action->ops;
struct sk_buff *skb;
- int ret;
- skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
- GFP_KERNEL);
+ skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL);
if (!skb)
- return -ENOBUFS;
+ return ERR_PTR(-ENOBUFS);
if (tca_get_fill(skb, actions, 0, 0, 0, RTM_DELACTION, 0, 1, NULL) <= 0) {
kfree_skb(skb);
- return -EINVAL;
+ return ERR_PTR(-EINVAL);
+ }
+
+ return skb;
+}
+
+static int tcf_reoffload_del_notify(struct net *net, struct tc_action *action)
+{
+ const struct tc_action_ops *ops = action->ops;
+ struct sk_buff *skb;
+ int ret;
+
+ if (!rtnl_notify_needed(net, 0, RTNLGRP_TC)) {
+ skb = NULL;
+ } else {
+ skb = tcf_reoffload_del_notify_msg(net, action);
+ if (IS_ERR(skb))
+ return PTR_ERR(skb);
}
ret = tcf_idr_release_unsafe(action);
if (ret == ACT_P_DELETED) {
module_put(ops->owner);
- ret = rtnetlink_send(skb, net, 0, RTNLGRP_TC, 0);
+ ret = rtnetlink_maybe_send(skb, net, 0, RTNLGRP_TC, 0);
} else {
kfree_skb(skb);
}
@@ -1870,23 +1912,41 @@ int tcf_action_reoffload_cb(flow_indr_block_bind_cb_t *cb,
return 0;
}
-static int
-tcf_del_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
- u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
+static struct sk_buff *tcf_del_notify_msg(struct net *net, struct nlmsghdr *n,
+ struct tc_action *actions[],
+ u32 portid, size_t attr_size,
+ struct netlink_ext_ack *extack)
{
- int ret;
struct sk_buff *skb;
- skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
- GFP_KERNEL);
+ skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL);
if (!skb)
- return -ENOBUFS;
+ return ERR_PTR(-ENOBUFS);
if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
0, 2, extack) <= 0) {
NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes");
kfree_skb(skb);
- return -EINVAL;
+ return ERR_PTR(-EINVAL);
+ }
+
+ return skb;
+}
+
+static int tcf_del_notify(struct net *net, struct nlmsghdr *n,
+ struct tc_action *actions[], u32 portid,
+ size_t attr_size, struct netlink_ext_ack *extack)
+{
+ struct sk_buff *skb;
+ int ret;
+
+ if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC)) {
+ skb = NULL;
+ } else {
+ skb = tcf_del_notify_msg(net, n, actions, portid, attr_size,
+ extack);
+ if (IS_ERR(skb))
+ return PTR_ERR(skb);
}
/* now do the delete */
@@ -1897,9 +1957,8 @@ tcf_del_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
return ret;
}
- ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
- n->nlmsg_flags & NLM_F_ECHO);
- return ret;
+ return rtnetlink_maybe_send(skb, net, portid, RTNLGRP_TC,
+ n->nlmsg_flags & NLM_F_ECHO);
}
static int
@@ -1950,26 +2009,44 @@ err:
return ret;
}
-static int
-tcf_add_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
- u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
+static struct sk_buff *tcf_add_notify_msg(struct net *net, struct nlmsghdr *n,
+ struct tc_action *actions[],
+ u32 portid, size_t attr_size,
+ struct netlink_ext_ack *extack)
{
struct sk_buff *skb;
- skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
- GFP_KERNEL);
+ skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL);
if (!skb)
- return -ENOBUFS;
+ return ERR_PTR(-ENOBUFS);
if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
RTM_NEWACTION, 0, 0, extack) <= 0) {
NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
kfree_skb(skb);
- return -EINVAL;
+ return ERR_PTR(-EINVAL);
}
- return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
- n->nlmsg_flags & NLM_F_ECHO);
+ return skb;
+}
+
+static int tcf_add_notify(struct net *net, struct nlmsghdr *n,
+ struct tc_action *actions[], u32 portid,
+ size_t attr_size, struct netlink_ext_ack *extack)
+{
+ struct sk_buff *skb;
+
+ if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC)) {
+ skb = NULL;
+ } else {
+ skb = tcf_add_notify_msg(net, n, actions, portid, attr_size,
+ extack);
+ if (IS_ERR(skb))
+ return PTR_ERR(skb);
+ }
+
+ return rtnetlink_maybe_send(skb, net, portid, RTNLGRP_TC,
+ n->nlmsg_flags & NLM_F_ECHO);
}
static int tcf_action_add(struct net *net, struct nlattr *nla,
@@ -1977,7 +2054,7 @@ static int tcf_action_add(struct net *net, struct nlattr *nla,
struct netlink_ext_ack *extack)
{
size_t attr_size = 0;
- int loop, ret, i;
+ int loop, ret;
struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
int init_res[TCA_ACT_MAX_PRIO] = {};
@@ -1990,13 +2067,11 @@ static int tcf_action_add(struct net *net, struct nlattr *nla,
if (ret < 0)
return ret;
+
ret = tcf_add_notify(net, n, actions, portid, attr_size, extack);
- /* only put existing actions */
- for (i = 0; i < TCA_ACT_MAX_PRIO; i++)
- if (init_res[i] == ACT_P_CREATED)
- actions[i] = NULL;
- tcf_action_put_many(actions);
+ /* only put bound actions */
+ tca_put_bound_many(actions, init_res);
return ret;
}