Re: [PATCH 06/14] net: sched: implement reference counted action release
From: Jiri Pirko <jiri@resnulli.us>
Date: 2018-05-14 16:47:57
Also in:
lkml, netfilter-devel
Mon, May 14, 2018 at 04:27:07PM CEST, vladbu@mellanox.com wrote: [...]
+static int tcf_action_del_1(struct net *net, char *kind, u32 index,
+ struct netlink_ext_ack *extack)
+{
+ const struct tc_action_ops *ops;
+ int err = -EINVAL;
+
+ ops = tc_lookup_action_n(kind);
+ if (!ops) {How this can happen? Apparently you hold reference to the module since you put it couple lines below. In that case, I don't really understand why you need to lookup and just don't use "ops" pointer you have in tcf_action_delete().
quoted hunk ↗ jump to hunk
+ NL_SET_ERR_MSG(extack, "Specified TC action not found"); + goto err_out; + } + + if (ops->delete) + err = ops->delete(net, index); + + module_put(ops->owner); +err_out: + return err; +} + static int tca_action_flush(struct net *net, struct nlattr *nla, struct nlmsghdr *n, u32 portid, struct netlink_ext_ack *extack)@@ -1052,6 +1088,36 @@ static int tca_action_flush(struct net *net, struct nlattr *nla,return err; } +static int tcf_action_delete(struct net *net, struct list_head *actions, + struct netlink_ext_ack *extack) +{ + int ret; + struct tc_action *a, *tmp; + char kind[IFNAMSIZ]; + u32 act_index; + + list_for_each_entry_safe(a, tmp, actions, list) { + 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. + */ + strncpy(kind, a->ops->kind, sizeof(kind) - 1); + act_index = a->tcfa_index; + + list_del(&a->list); + if (tcf_action_put(a)) + module_put(ops->owner); + + /* now do the delete */ + ret = tcf_action_del_1(net, kind, act_index, extack); + if (ret < 0) + return ret; + } + return 0; +} +
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