diff options
| -rw-r--r-- | net/sched/cls_basic.c | 80 |
1 files changed, 45 insertions, 35 deletions
diff --git a/net/sched/cls_basic.c b/net/sched/cls_basic.c index 0ae1813e3e90..1937298d6775 100644 --- a/net/sched/cls_basic.c +++ b/net/sched/cls_basic.c @@ -24,6 +24,7 @@ struct basic_head { u32 hgenerator; struct list_head flist; + struct rcu_head rcu; }; struct basic_filter { @@ -31,17 +32,19 @@ struct basic_filter { struct tcf_exts exts; struct tcf_ematch_tree ematches; struct tcf_result res; + struct tcf_proto *tp; struct list_head link; + struct rcu_head rcu; }; static int basic_classify(struct sk_buff *skb, const struct tcf_proto *tp, struct tcf_result *res) { int r; - struct basic_head *head = tp->root; + struct basic_head *head = rcu_dereference_bh(tp->root); struct basic_filter *f; - list_for_each_entry(f, &head->flist, link) { + list_for_each_entry_rcu(f, &head->flist, link) { if (!tcf_em_tree_match(skb, &f->ematches, NULL)) continue; *res = f->res; @@ -56,7 +59,7 @@ static int basic_classify(struct sk_buff *skb, const struct tcf_proto *tp, static unsigned long basic_get(struct tcf_proto *tp, u32 handle) { unsigned long l = 0UL; - struct basic_head *head = tp->root; + struct basic_head *head = rtnl_dereference(tp->root); struct basic_filter *f; if (head == NULL) @@ -81,12 +84,15 @@ static int basic_init(struct tcf_proto *tp) if (head == NULL) return -ENOBUFS; INIT_LIST_HEAD(&head->flist); - tp->root = head; + rcu_assign_pointer(tp->root, head); return 0; } -static void basic_delete_filter(struct tcf_proto *tp, struct basic_filter *f) +static void basic_delete_filter(struct rcu_head *head) { + struct basic_filter *f = container_of(head, struct basic_filter, rcu); + struct tcf_proto *tp = f->tp; + tcf_unbind_filter(tp, &f->res); tcf_exts_destroy(tp, &f->exts); tcf_em_tree_destroy(tp, &f->ematches); @@ -95,27 +101,26 @@ static void basic_delete_filter(struct tcf_proto *tp, struct basic_filter *f) static void basic_destroy(struct tcf_proto *tp) { - struct basic_head *head = tp->root; + struct basic_head *head = rtnl_dereference(tp->root); struct basic_filter *f, *n; list_for_each_entry_safe(f, n, &head->flist, link) { - list_del(&f->link); - basic_delete_filter(tp, f); + list_del_rcu(&f->link); + call_rcu(&f->rcu, basic_delete_filter); } - kfree(head); + RCU_INIT_POINTER(tp->root, NULL); + kfree_rcu(head, rcu); } static int basic_delete(struct tcf_proto *tp, unsigned long arg) { - struct basic_head *head = tp->root; + struct basic_head *head = rtnl_dereference(tp->root); struct basic_filter *t, *f = (struct basic_filter *) arg; list_for_each_entry(t, &head->flist, link) if (t == f) { - tcf_tree_lock(tp); - list_del(&t->link); - tcf_tree_unlock(tp); - basic_delete_filter(tp, t); + list_del_rcu(&t->link); + call_rcu(&t->rcu, basic_delete_filter); return 0; } @@ -152,6 +157,7 @@ static int basic_set_parms(struct net *net, struct tcf_proto *tp, tcf_exts_change(tp, &f->exts, &e); tcf_em_tree_change(tp, &f->ematches, &t); + f->tp = tp; return 0; errout: @@ -164,9 +170,10 @@ static int basic_change(struct net *net, struct sk_buff *in_skb, struct nlattr **tca, unsigned long *arg, bool ovr) { int err; - struct basic_head *head = tp->root; + struct basic_head *head = rtnl_dereference(tp->root); struct nlattr *tb[TCA_BASIC_MAX + 1]; - struct basic_filter *f = (struct basic_filter *) *arg; + struct basic_filter *fold = (struct basic_filter *) *arg; + struct basic_filter *fnew; if (tca[TCA_OPTIONS] == NULL) return -EINVAL; @@ -176,22 +183,23 @@ static int basic_change(struct net *net, struct sk_buff *in_skb, if (err < 0) return err; - if (f != NULL) { - if (handle && f->handle != handle) + if (fold != NULL) { + if (handle && fold->handle != handle) return -EINVAL; - return basic_set_parms(net, tp, f, base, tb, tca[TCA_RATE], ovr); } err = -ENOBUFS; - f = kzalloc(sizeof(*f), GFP_KERNEL); - if (f == NULL) + fnew = kzalloc(sizeof(*fnew), GFP_KERNEL); + if (fnew == NULL) goto errout; - tcf_exts_init(&f->exts, TCA_BASIC_ACT, TCA_BASIC_POLICE); + tcf_exts_init(&fnew->exts, TCA_BASIC_ACT, TCA_BASIC_POLICE); err = -EINVAL; - if (handle) - f->handle = handle; - else { + if (handle) { + fnew->handle = handle; + } else if (fold) { + fnew->handle = fold->handle; + } else { unsigned int i = 0x80000000; do { if (++head->hgenerator == 0x7FFFFFFF) @@ -203,29 +211,31 @@ static int basic_change(struct net *net, struct sk_buff *in_skb, goto errout; } - f->handle = head->hgenerator; + fnew->handle = head->hgenerator; } - err = basic_set_parms(net, tp, f, base, tb, tca[TCA_RATE], ovr); + err = basic_set_parms(net, tp, fnew, base, tb, tca[TCA_RATE], ovr); if (err < 0) goto errout; - tcf_tree_lock(tp); - list_add(&f->link, &head->flist); - tcf_tree_unlock(tp); - *arg = (unsigned long) f; + *arg = (unsigned long)fnew; + + if (fold) { + list_replace_rcu(&fold->link, &fnew->link); + call_rcu(&fold->rcu, basic_delete_filter); + } else { + list_add_rcu(&fnew->link, &head->flist); + } return 0; errout: - if (*arg == 0UL && f) - kfree(f); - + kfree(fnew); return err; } static void basic_walk(struct tcf_proto *tp, struct tcf_walker *arg) { - struct basic_head *head = tp->root; + struct basic_head *head = rtnl_dereference(tp->root); struct basic_filter *f; list_for_each_entry(f, &head->flist, link) { |