diff options
Diffstat (limited to 'net/sched/cls_api.c')
| -rw-r--r-- | net/sched/cls_api.c | 80 |
1 files changed, 56 insertions, 24 deletions
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c index c743f03cfebd..ecbb019efcbd 100644 --- a/net/sched/cls_api.c +++ b/net/sched/cls_api.c @@ -77,6 +77,8 @@ out: } EXPORT_SYMBOL(register_tcf_proto_ops); +static struct workqueue_struct *tc_filter_wq; + int unregister_tcf_proto_ops(struct tcf_proto_ops *ops) { struct tcf_proto_ops *t; @@ -86,6 +88,7 @@ int unregister_tcf_proto_ops(struct tcf_proto_ops *ops) * tcf_proto_ops's destroy() handler. */ rcu_barrier(); + flush_workqueue(tc_filter_wq); write_lock(&cls_mod_lock); list_for_each_entry(t, &tcf_proto_base, head) { @@ -100,6 +103,12 @@ int unregister_tcf_proto_ops(struct tcf_proto_ops *ops) } EXPORT_SYMBOL(unregister_tcf_proto_ops); +bool tcf_queue_work(struct work_struct *work) +{ + return queue_work(tc_filter_wq, work); +} +EXPORT_SYMBOL(tcf_queue_work); + /* Select new prio value from the range, managed by kernel. */ static inline u32 tcf_auto_prio(struct tcf_proto *tp) @@ -182,7 +191,7 @@ static struct tcf_chain *tcf_chain_create(struct tcf_block *block, list_add_tail(&chain->list, &block->chain_list); chain->block = block; chain->index = chain_index; - chain->refcnt = 0; + chain->refcnt = 1; return chain; } @@ -194,21 +203,20 @@ static void tcf_chain_flush(struct tcf_chain *chain) RCU_INIT_POINTER(*chain->p_filter_chain, NULL); while ((tp = rtnl_dereference(chain->filter_chain)) != NULL) { RCU_INIT_POINTER(chain->filter_chain, tp->next); + tcf_chain_put(chain); tcf_proto_destroy(tp); } } static void tcf_chain_destroy(struct tcf_chain *chain) { - /* May be already removed from the list by the previous call. */ - if (!list_empty(&chain->list)) - list_del_init(&chain->list); + list_del(&chain->list); + kfree(chain); +} - /* There might still be a reference held when we got here from - * tcf_block_put. Wait for the user to drop reference before free. - */ - if (!chain->refcnt) - kfree(chain); +static void tcf_chain_hold(struct tcf_chain *chain) +{ + ++chain->refcnt; } struct tcf_chain *tcf_chain_get(struct tcf_block *block, u32 chain_index, @@ -217,24 +225,19 @@ struct tcf_chain *tcf_chain_get(struct tcf_block *block, u32 chain_index, struct tcf_chain *chain; list_for_each_entry(chain, &block->chain_list, list) { - if (chain->index == chain_index) - goto incref; + if (chain->index == chain_index) { + tcf_chain_hold(chain); + return chain; + } } - chain = create ? tcf_chain_create(block, chain_index) : NULL; -incref: - if (chain) - chain->refcnt++; - return chain; + return create ? tcf_chain_create(block, chain_index) : NULL; } EXPORT_SYMBOL(tcf_chain_get); void tcf_chain_put(struct tcf_chain *chain) { - /* Destroy unused chain, with exception of chain 0, which is the - * default one and has to be always present. - */ - if (--chain->refcnt == 0 && !chain->filter_chain && chain->index != 0) + if (--chain->refcnt == 0) tcf_chain_destroy(chain); } EXPORT_SYMBOL(tcf_chain_put); @@ -272,6 +275,23 @@ err_chain_create: } EXPORT_SYMBOL(tcf_block_get); +static void tcf_block_put_final(struct work_struct *work) +{ + struct tcf_block *block = container_of(work, struct tcf_block, work); + struct tcf_chain *chain, *tmp; + + rtnl_lock(); + /* Only chain 0 should be still here. */ + list_for_each_entry_safe(chain, tmp, &block->chain_list, list) + tcf_chain_put(chain); + rtnl_unlock(); + kfree(block); +} + +/* XXX: Standalone actions are not allowed to jump to any chain, and bound + * actions should be all removed after flushing. However, filters are now + * destroyed in tc filter workqueue with RTNL lock, they can not race here. + */ void tcf_block_put(struct tcf_block *block) { struct tcf_chain *chain, *tmp; @@ -279,11 +299,15 @@ void tcf_block_put(struct tcf_block *block) if (!block) return; - list_for_each_entry_safe(chain, tmp, &block->chain_list, list) { + list_for_each_entry_safe(chain, tmp, &block->chain_list, list) tcf_chain_flush(chain); - tcf_chain_destroy(chain); - } - kfree(block); + + INIT_WORK(&block->work, tcf_block_put_final); + /* Wait for RCU callbacks to release the reference count and make + * sure their works have been queued before this. + */ + rcu_barrier(); + tcf_queue_work(&block->work); } EXPORT_SYMBOL(tcf_block_put); @@ -360,6 +384,7 @@ static void tcf_chain_tp_insert(struct tcf_chain *chain, rcu_assign_pointer(*chain->p_filter_chain, tp); RCU_INIT_POINTER(tp->next, tcf_chain_tp_prev(chain_info)); rcu_assign_pointer(*chain_info->pprev, tp); + tcf_chain_hold(chain); } static void tcf_chain_tp_remove(struct tcf_chain *chain, @@ -371,6 +396,7 @@ static void tcf_chain_tp_remove(struct tcf_chain *chain, if (chain->p_filter_chain && tp == chain->filter_chain) RCU_INIT_POINTER(*chain->p_filter_chain, next); RCU_INIT_POINTER(*chain_info->pprev, next); + tcf_chain_put(chain); } static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain, @@ -862,6 +888,7 @@ void tcf_exts_destroy(struct tcf_exts *exts) #ifdef CONFIG_NET_CLS_ACT LIST_HEAD(actions); + ASSERT_RTNL(); tcf_exts_to_list(exts, &actions); tcf_action_destroy(&actions, TCA_ACT_UNBIND); kfree(exts->actions); @@ -900,6 +927,7 @@ int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb, exts->actions[i++] = act; exts->nr_actions = i; } + exts->net = net; } #else if ((exts->action && tb[exts->action]) || @@ -1013,6 +1041,10 @@ EXPORT_SYMBOL(tcf_exts_get_dev); static int __init tc_filter_init(void) { + tc_filter_wq = alloc_ordered_workqueue("tc_filter_workqueue", 0); + if (!tc_filter_wq) + return -ENOMEM; + rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_ctl_tfilter, NULL, 0); rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_ctl_tfilter, NULL, 0); rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_ctl_tfilter, |