/* * net/sched/cls_cgroup.c Control Group Classifier * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * * Authors: Thomas Graf */ #include #include #include #include #include #include #include #include struct cls_cgroup_head { u32 handle; struct tcf_exts exts; struct tcf_ematch_tree ematches; struct tcf_proto *tp; struct rcu_work rwork; }; static int cls_cgroup_classify(struct sk_buff *skb, const struct tcf_proto *tp, struct tcf_result *res) { struct cls_cgroup_head *head = rcu_dereference_bh(tp->root); u32 classid = task_get_classid(skb); if (!classid) return -1; if (!tcf_em_tree_match(skb, &head->ematches, NULL)) return -1; res->classid = classid; res->class = 0; return tcf_exts_exec(skb, &head->exts, res); } static void *cls_cgroup_get(struct tcf_proto *tp, u32 handle) { return NULL; } static int cls_cgroup_init(struct tcf_proto *tp) { return 0; } static const struct nla_policy cgroup_policy[TCA_CGROUP_MAX + 1] = { [TCA_CGROUP_EMATCHES] = { .type = NLA_NESTED }, }; static void __cls_cgroup_destroy(struct cls_cgroup_head *head) { tcf_exts_destroy(&head->exts); tcf_em_tree_destroy(&head->ematches); tcf_exts_put_net(&head->exts); kfree(head); } static void cls_cgroup_destroy_work(struct work_struct *work) { struct cls_cgroup_head *head = container_of(to_rcu_work(work), struct cls_cgroup_head, rwork); rtnl_lock(); __cls_cgroup_destroy(head); rtnl_unlock(); } static int cls_cgroup_change(struct net *net, struct sk_buff *in_skb, struct tcf_proto *tp, unsigned long base, u32 handle, struct nlattr **tca, void **arg, bool ovr, bool rtnl_held, struct netlink_ext_ack *extack) { struct nlattr *tb[TCA_CGROUP_MAX + 1]; struct cls_cgroup_head *head = rtnl_dereference(tp->root); struct cls_cgroup_head *new; int err; if (!tca[TCA_OPTIONS]) return -EINVAL; if (!head && !handle) return -EINVAL; if (head && handle != head->handle) return -ENOENT; new = kzalloc(sizeof(*head), GFP_KERNEL); if (!new) return -ENOBUFS; err = tcf_exts_init(&new->exts, TCA_CGROUP_ACT, TCA_CGROUP_POLICE); if (err < 0) goto errout; new->handle = handle; new->tp = tp; err = nla_parse_nested(tb, TCA_CGROUP_MAX, tca[TCA_OPTIONS], cgroup_policy, NULL); if (err < 0) goto errout; err = tcf_exts_validate(net, tp, tb, tca[TCA_RATE], &new->exts, ovr, true, extack); if (err < 0) goto errout; err = tcf_em_tree_validate(tp, tb[TCA_CGROUP_EMATCHES], &new->ematches); if (err < 0) goto errout; rcu_assign_pointer(tp->root, new); if (head) { tcf_exts_get_net(&head->exts); tcf_queue_work(&head->rwork, cls_cgroup_destroy_work); } return 0; errout: tcf_exts_destroy(&new->exts); kfree(new); return err; } static void cls_cgroup_destroy(struct tcf_proto *tp, bool rtnl_held, struct netlink_ext_ack *extack) { struct cls_cgroup_head *head = rtnl_dereference(tp->root); /* Head can still be NULL due to cls_cgroup_init(). */ if (head) { if (tcf_exts_get_net(&head->exts)) tcf_queue_work(&head->rwork, cls_cgroup_destroy_work); else __cls_cgroup_destroy(head); } } static int cls_cgroup_delete(struct tcf_proto *tp, void *arg, bool *last, bool rtnl_held, struct netlink_ext_ack *extack) { return -EOPNOTSUPP; } static void cls_cgroup_walk(struct tcf_proto *tp, struct tcf_walker *arg, bool rtnl_held) { struct cls_cgroup_head *head = rtnl_dereference(tp->root); if (arg->count < arg->skip) goto skip; if (!head) return; if (arg->fn(tp, head, arg) < 0) { arg->stop = 1; return; } skip: arg->count++; } static int cls_cgroup_dump(struct net *net, struct tcf_proto *tp, void *fh, struct sk_buff *skb, struct tcmsg *t, bool rtnl_held) { struct cls_cgroup_head *head = rtnl_dereference(tp->root); struct nlattr *nest; t->tcm_handle = head->handle; nest = nla_nest_start(skb, TCA_OPTIONS); if (nest == NULL) goto nla_put_failure; if (tcf_exts_dump(skb, &head->exts) < 0 || tcf_em_tree_dump(skb, &head->ematches, TCA_CGROUP_EMATCHES) < 0) goto nla_put_failure; nla_nest_end(skb, nest); if (tcf_exts_dump_stats(skb, &head->exts) < 0) goto nla_put_failure; return skb->len; nla_put_failure: nla_nest_cancel(skb, nest); return -1; } static struct tcf_proto_ops cls_cgroup_ops __read_mostly = { .kind = "cgroup", .init = cls_cgroup_init, .change = cls_cgroup_change, .classify = cls_cgroup_classify, .destroy = cls_cgroup_destroy, .get = cls_cgroup_get, .delete = cls_cgroup_delete, .walk = cls_cgroup_walk, .dump = cls_cgroup_dump, .owner = THIS_MODULE, }; static int __init init_cgroup_cls(void) { return register_tcf_proto_ops(&cls_cgroup_ops); } static void __exit exit_cgroup_cls(void) { unregister_tcf_proto_ops(&cls_cgroup_ops); } module_init(init_cgroup_cls); module_exit(exit_cgroup_cls); MODULE_LICENSE("GPL");