cregit-Linux how code gets into the kernel

Release 4.11 net/sched/act_api.c

Directory: net/sched
/*
 * net/sched/act_api.c  Packet action API.
 *
 *              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.
 *
 * Author:      Jamal Hadi Salim
 *
 *
 */

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/skbuff.h>
#include <linux/init.h>
#include <linux/kmod.h>
#include <linux/err.h>
#include <linux/module.h>
#include <net/net_namespace.h>
#include <net/sock.h>
#include <net/sch_generic.h>
#include <net/pkt_cls.h>
#include <net/act_api.h>
#include <net/netlink.h>


static void free_tcf(struct rcu_head *head) { struct tc_action *p = container_of(head, struct tc_action, tcfa_rcu); free_percpu(p->cpu_bstats); free_percpu(p->cpu_qstats); if (p->act_cookie) { kfree(p->act_cookie->data); kfree(p->act_cookie); } kfree(p); }

Contributors

PersonTokensPropCommitsCommitProp
Eric Dumazet4260.87%133.33%
Jamal Hadi Salim2434.78%133.33%
Américo Wang34.35%133.33%
Total69100.00%3100.00%


static void tcf_hash_destroy(struct tcf_hashinfo *hinfo, struct tc_action *p) { spin_lock_bh(&hinfo->lock); hlist_del(&p->tcfa_head); spin_unlock_bh(&hinfo->lock); gen_kill_estimator(&p->tcfa_rate_est); /* * gen_estimator est_timer() might access p->tcfa_lock * or bstats, wait a RCU grace period before freeing p */ call_rcu(&p->tcfa_rcu, free_tcf); }

Contributors

PersonTokensPropCommitsCommitProp
David S. Miller3152.54%112.50%
Américo Wang2237.29%562.50%
Eric Dumazet58.47%112.50%
Alexei Starovoitov11.69%112.50%
Total59100.00%8100.00%


int __tcf_hash_release(struct tc_action *p, bool bind, bool strict) { int ret = 0; if (p) { if (bind) p->tcfa_bindcnt--; else if (strict && p->tcfa_bindcnt > 0) return -EPERM; p->tcfa_refcnt--; if (p->tcfa_bindcnt <= 0 && p->tcfa_refcnt <= 0) { if (p->ops->cleanup) p->ops->cleanup(p, bind); tcf_hash_destroy(p->hinfo, p); ret = ACT_P_DELETED; } } return ret; }

Contributors

PersonTokensPropCommitsCommitProp
David S. Miller5652.34%112.50%
Américo Wang4441.12%675.00%
Daniel Borkmann76.54%112.50%
Total107100.00%8100.00%

EXPORT_SYMBOL(__tcf_hash_release);
static int tcf_dump_walker(struct tcf_hashinfo *hinfo, struct sk_buff *skb, struct netlink_callback *cb) { int err = 0, index = -1, i = 0, s_i = 0, n_i = 0; struct nlattr *nest; spin_lock_bh(&hinfo->lock); s_i = cb->args[0]; for (i = 0; i < (hinfo->hmask + 1); i++) { struct hlist_head *head; struct tc_action *p; head = &hinfo->htab[tcf_hash(i, hinfo->hmask)]; hlist_for_each_entry_rcu(p, head, tcfa_head) { index++; if (index < s_i) continue; nest = nla_nest_start(skb, n_i); if (nest == NULL) goto nla_put_failure; err = tcf_action_dump_1(skb, p, 0, 0); if (err < 0) { index--; nlmsg_trim(skb, nest); goto done; } nla_nest_end(skb, nest); n_i++; if (n_i >= TCA_ACT_MAX_PRIO) goto done; } } done: spin_unlock_bh(&hinfo->lock); if (n_i) cb->args[0] += n_i; return n_i; nla_put_failure: nla_nest_cancel(skb, nest); goto done; }

Contributors

PersonTokensPropCommitsCommitProp
David S. Miller18476.03%18.33%
Américo Wang3313.64%650.00%
Patrick McHardy208.26%216.67%
Arnaldo Carvalho de Melo31.24%216.67%
Jamal Hadi Salim20.83%18.33%
Total242100.00%12100.00%


static int tcf_del_walker(struct tcf_hashinfo *hinfo, struct sk_buff *skb, const struct tc_action_ops *ops) { struct nlattr *nest; int i = 0, n_i = 0; int ret = -EINVAL; nest = nla_nest_start(skb, 0); if (nest == NULL) goto nla_put_failure; if (nla_put_string(skb, TCA_KIND, ops->kind)) goto nla_put_failure; for (i = 0; i < (hinfo->hmask + 1); i++) { struct hlist_head *head; struct hlist_node *n; struct tc_action *p; head = &hinfo->htab[tcf_hash(i, hinfo->hmask)]; hlist_for_each_entry_safe(p, n, head, tcfa_head) { ret = __tcf_hash_release(p, false, true); if (ret == ACT_P_DELETED) { module_put(p->ops->owner); n_i++; } else if (ret < 0) goto nla_put_failure; } } if (nla_put_u32(skb, TCA_FCNT, n_i)) goto nla_put_failure; nla_nest_end(skb, nest); return n_i; nla_put_failure: nla_nest_cancel(skb, nest); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
David S. Miller12657.80%215.38%
Américo Wang6529.82%646.15%
Patrick McHardy198.72%215.38%
Daniel Borkmann41.83%17.69%
Jamal Hadi Salim20.92%17.69%
Arnaldo Carvalho de Melo20.92%17.69%
Total218100.00%13100.00%


int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb, struct netlink_callback *cb, int type, const struct tc_action_ops *ops) { struct tcf_hashinfo *hinfo = tn->hinfo; if (type == RTM_DELACTION) { return tcf_del_walker(hinfo, skb, ops); } else if (type == RTM_GETACTION) { return tcf_dump_walker(hinfo, skb, cb); } else { WARN(1, "tcf_generic_walker: unknown action %d\n", type); return -EINVAL; } }

Contributors

PersonTokensPropCommitsCommitProp
David S. Miller6672.53%125.00%
Américo Wang2224.18%250.00%
Stephen Hemminger33.30%125.00%
Total91100.00%4100.00%

EXPORT_SYMBOL(tcf_generic_walker);
static struct tc_action *tcf_hash_lookup(u32 index, struct tcf_hashinfo *hinfo) { struct tc_action *p = NULL; struct hlist_head *head; spin_lock_bh(&hinfo->lock); head = &hinfo->htab[tcf_hash(index, hinfo->hmask)]; hlist_for_each_entry_rcu(p, head, tcfa_head) if (p->tcfa_index == index) break; spin_unlock_bh(&hinfo->lock); return p; }

Contributors

PersonTokensPropCommitsCommitProp
David S. Miller5567.90%120.00%
Américo Wang2632.10%480.00%
Total81100.00%5100.00%


u32 tcf_hash_new_index(struct tc_action_net *tn) { struct tcf_hashinfo *hinfo = tn->hinfo; u32 val = hinfo->index; do { if (++val == 0) val = 1; } while (tcf_hash_lookup(val, hinfo)); hinfo->index = val; return val; }

Contributors

PersonTokensPropCommitsCommitProp
David S. Miller3966.10%125.00%
Américo Wang1728.81%250.00%
Yang Yingliang35.08%125.00%
Total59100.00%4100.00%

EXPORT_SYMBOL(tcf_hash_new_index);
int tcf_hash_search(struct tc_action_net *tn, struct tc_action **a, u32 index) { struct tcf_hashinfo *hinfo = tn->hinfo; struct tc_action *p = tcf_hash_lookup(index, hinfo); if (p) { *a = p; return 1; } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
David S. Miller4782.46%125.00%
Américo Wang1017.54%375.00%
Total57100.00%4100.00%

EXPORT_SYMBOL(tcf_hash_search);
bool tcf_hash_check(struct tc_action_net *tn, u32 index, struct tc_action **a, int bind) { struct tcf_hashinfo *hinfo = tn->hinfo; struct tc_action *p = NULL; if (index && (p = tcf_hash_lookup(index, hinfo)) != NULL) { if (bind) p->tcfa_bindcnt++; p->tcfa_refcnt++; *a = p; return true; } return false; }

Contributors

PersonTokensPropCommitsCommitProp
David S. Miller5971.95%114.29%
Américo Wang2328.05%685.71%
Total82100.00%7100.00%

EXPORT_SYMBOL(tcf_hash_check);
void tcf_hash_cleanup(struct tc_action *a, struct nlattr *est) { if (est) gen_kill_estimator(&a->tcfa_rate_est); call_rcu(&a->tcfa_rcu, free_tcf); }

Contributors

PersonTokensPropCommitsCommitProp
Américo Wang3286.49%266.67%
Eric Dumazet513.51%133.33%
Total37100.00%3100.00%

EXPORT_SYMBOL(tcf_hash_cleanup);
int tcf_hash_create(struct tc_action_net *tn, u32 index, struct nlattr *est, struct tc_action **a, const struct tc_action_ops *ops, int bind, bool cpustats) { struct tc_action *p = kzalloc(ops->size, GFP_KERNEL); struct tcf_hashinfo *hinfo = tn->hinfo; int err = -ENOMEM; if (unlikely(!p)) return -ENOMEM; p->tcfa_refcnt = 1; if (bind) p->tcfa_bindcnt = 1; if (cpustats) { p->cpu_bstats = netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu); if (!p->cpu_bstats) { err1: kfree(p); return err; } p->cpu_qstats = alloc_percpu(struct gnet_stats_queue); if (!p->cpu_qstats) { err2: free_percpu(p->cpu_bstats); goto err1; } } spin_lock_init(&p->tcfa_lock); INIT_HLIST_NODE(&p->tcfa_head); p->tcfa_index = index ? index : tcf_hash_new_index(tn); p->tcfa_tm.install = jiffies; p->tcfa_tm.lastuse = jiffies; p->tcfa_tm.firstuse = 0; if (est) { err = gen_new_estimator(&p->tcfa_bstats, p->cpu_bstats, &p->tcfa_rate_est, &p->tcfa_lock, NULL, est); if (err) { free_percpu(p->cpu_qstats); goto err2; } } p->hinfo = hinfo; p->ops = ops; INIT_LIST_HEAD(&p->list); *a = p; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
David S. Miller10937.59%16.67%
Eric Dumazet8830.34%213.33%
Américo Wang6723.10%640.00%
Stephen Hemminger144.83%16.67%
Jamal Hadi Salim93.10%213.33%
Patrick McHardy20.69%213.33%
John Fastabend10.34%16.67%
Total290100.00%15100.00%

EXPORT_SYMBOL(tcf_hash_create);
void tcf_hash_insert(struct tc_action_net *tn, struct tc_action *a) { struct tcf_hashinfo *hinfo = tn->hinfo; unsigned int h = tcf_hash(a->tcfa_index, hinfo->hmask); spin_lock_bh(&hinfo->lock); hlist_add_head(&a->tcfa_head, &hinfo->htab[h]); spin_unlock_bh(&hinfo->lock); }

Contributors

PersonTokensPropCommitsCommitProp
David S. Miller4056.34%114.29%
Américo Wang3042.25%571.43%
Jamal Hadi Salim11.41%114.29%
Total71100.00%7100.00%

EXPORT_SYMBOL(tcf_hash_insert);
void tcf_hashinfo_destroy(const struct tc_action_ops *ops, struct tcf_hashinfo *hinfo) { int i; for (i = 0; i < hinfo->hmask + 1; i++) { struct tc_action *p; struct hlist_node *n; hlist_for_each_entry_safe(p, n, &hinfo->htab[i], tcfa_head) { int ret; ret = __tcf_hash_release(p, false, true); if (ret == ACT_P_DELETED) module_put(ops->owner); else if (ret < 0) return; } } kfree(hinfo->htab); }

Contributors

PersonTokensPropCommitsCommitProp
Américo Wang102100.00%4100.00%
Total102100.00%4100.00%

EXPORT_SYMBOL(tcf_hashinfo_destroy); static LIST_HEAD(act_base); static DEFINE_RWLOCK(act_mod_lock);
int tcf_register_action(struct tc_action_ops *act, struct pernet_operations *ops) { struct tc_action_ops *a; int ret; if (!act->act || !act->dump || !act->init || !act->walk || !act->lookup) return -EINVAL; /* We have to register pernet ops before making the action ops visible, * otherwise tcf_action_init_1() could get a partially initialized * netns. */ ret = register_pernet_subsys(ops); if (ret) return ret; write_lock(&act_mod_lock); list_for_each_entry(a, &act_base, head) { if (act->type == a->type || (strcmp(act->kind, a->kind) == 0)) { write_unlock(&act_mod_lock); unregister_pernet_subsys(ops); return -EEXIST; } } list_add_tail(&act->head, &act_base); write_unlock(&act_mod_lock); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Jamal Hadi Salim9262.59%450.00%
Américo Wang5537.41%450.00%
Total147100.00%8100.00%

EXPORT_SYMBOL(tcf_register_action);
int tcf_unregister_action(struct tc_action_ops *act, struct pernet_operations *ops) { struct tc_action_ops *a; int err = -ENOENT; write_lock(&act_mod_lock); list_for_each_entry(a, &act_base, head) { if (a == act) { list_del(&act->head); err = 0; break; } } write_unlock(&act_mod_lock); if (!err) unregister_pernet_subsys(ops); return err; }

Contributors

PersonTokensPropCommitsCommitProp
Jamal Hadi Salim5060.98%120.00%
Américo Wang2935.37%360.00%
Eric Dumazet33.66%120.00%
Total82100.00%5100.00%

EXPORT_SYMBOL(tcf_unregister_action); /* lookup by name */
static struct tc_action_ops *tc_lookup_action_n(char *kind) { struct tc_action_ops *a, *res = NULL; if (kind) { read_lock(&act_mod_lock); list_for_each_entry(a, &act_base, head) { if (strcmp(kind, a->kind) == 0) { if (try_module_get(a->owner)) res = a; break; } } read_unlock(&act_mod_lock); } return res; }

Contributors

PersonTokensPropCommitsCommitProp
Jamal Hadi Salim6680.49%240.00%
Américo Wang89.76%120.00%
Eric Dumazet78.54%120.00%
Patrick McHardy11.22%120.00%
Total82100.00%5100.00%

/* lookup by nlattr */
static struct tc_action_ops *tc_lookup_action(struct nlattr *kind) { struct tc_action_ops *a, *res = NULL; if (kind) { read_lock(&act_mod_lock); list_for_each_entry(a, &act_base, head) { if (nla_strcmp(kind, a->kind) == 0) { if (try_module_get(a->owner)) res = a; break; } } read_unlock(&act_mod_lock); } return res; }

Contributors

PersonTokensPropCommitsCommitProp
Jamal Hadi Salim6578.31%233.33%
Américo Wang89.64%116.67%
Eric Dumazet78.43%116.67%
Patrick McHardy33.61%233.33%
Total83100.00%6100.00%


int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions, int nr_actions, struct tcf_result *res) { int ret = -1, i; if (skb_skip_tc_classify(skb)) return TC_ACT_OK; for (i = 0; i < nr_actions; i++) { const struct tc_action *a = actions[i]; repeat: ret = a->ops->act(skb, a, res); if (ret == TC_ACT_REPEAT) goto repeat; /* we need a ttl - JHS */ if (ret != TC_ACT_PIPE) break; } return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Jamal Hadi Salim6158.10%228.57%
Américo Wang3230.48%228.57%
Willem de Bruijn54.76%114.29%
David S. Miller54.76%114.29%
Patrick McHardy21.90%114.29%
Total105100.00%7100.00%

EXPORT_SYMBOL(tcf_action_exec);
int tcf_action_destroy(struct list_head *actions, int bind) { struct tc_action *a, *tmp; int ret = 0; list_for_each_entry_safe(a, tmp, actions, list) { ret = __tcf_hash_release(a, bind, true); if (ret == ACT_P_DELETED) module_put(a->ops->owner); else if (ret < 0) return ret; } return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Américo Wang4051.95%233.33%
Jamal Hadi Salim3241.56%233.33%
Daniel Borkmann33.90%116.67%
Patrick McHardy22.60%116.67%
Total77100.00%6100.00%


int tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref) { return a->ops->dump(skb, a, bind, ref); }

Contributors

PersonTokensPropCommitsCommitProp
Jamal Hadi Salim37100.00%1100.00%
Total37100.00%1100.00%


int tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref) { int err = -EINVAL; unsigned char *b = skb_tail_pointer(skb); struct nlattr *nest; if (nla_put_string(skb, TCA_KIND, a->ops->kind)) goto nla_put_failure; if (tcf_action_copy_stats(skb, a, 0)) goto nla_put_failure; if (a->act_cookie) { if (nla_put(skb, TCA_ACT_COOKIE, a->act_cookie->len, a->act_cookie->data)) goto nla_put_failure; } nest = nla_nest_start(skb, TCA_OPTIONS); if (nest == NULL) goto nla_put_failure; err = tcf_action_dump_old(skb, a, bind, ref); if (err > 0) { nla_nest_end(skb, nest); return err; } nla_put_failure: nlmsg_trim(skb, b); return -1; }

Contributors

PersonTokensPropCommitsCommitProp
Jamal Hadi Salim13580.36%222.22%
Patrick McHardy169.52%222.22%
Arnaldo Carvalho de Melo63.57%222.22%
David S. Miller52.98%111.11%
Eric Dumazet42.38%111.11%
Thomas Graf21.19%111.11%
Total168100.00%9100.00%

EXPORT_SYMBOL(tcf_action_dump_1);
int tcf_action_dump(struct sk_buff *skb, struct list_head *actions, int bind, int ref) { struct tc_action *a; int err = -EINVAL; struct nlattr *nest; list_for_each_entry(a, actions, list) { nest = nla_nest_start(skb, a->order); if (nest == NULL) goto nla_put_failure; err = tcf_action_dump_1(skb, a, bind, ref); if (err < 0) goto errout; nla_nest_end(skb, nest); } return 0; nla_put_failure: err = -EINVAL; errout: nla_nest_cancel(skb, nest); return err; }

Contributors

PersonTokensPropCommitsCommitProp
Jamal Hadi Salim7664.41%225.00%
Patrick McHardy2218.64%337.50%
Américo Wang108.47%112.50%
Thomas Graf86.78%112.50%
Arnaldo Carvalho de Melo21.69%112.50%
Total118100.00%8100.00%


static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb) { struct tc_cookie *c = kzalloc(sizeof(*c), GFP_KERNEL); if (!c) return NULL; c->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL); if (!c->data) { kfree(c); return NULL; } c->len = nla_len(tb[TCA_ACT_COOKIE]); return c; }

Contributors

PersonTokensPropCommitsCommitProp
Jamal Hadi Salim6577.38%133.33%
Wolfgang Bumiller1821.43%133.33%
Wei Yongjun11.19%133.33%
Total84100.00%3100.00%


struct tc_action *tcf_action_init_1(struct net *net, struct nlattr *nla, struct nlattr *est, char *name, int ovr, int bind) { struct tc_action *a; struct tc_action_ops *a_o; struct tc_cookie *cookie = NULL; char act_name[IFNAMSIZ]; struct nlattr *tb[TCA_ACT_MAX + 1]; struct nlattr *kind; int err; if (name == NULL) { err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL); if (err < 0) goto err_out; err = -EINVAL; kind = tb[TCA_ACT_KIND]; if (kind == NULL) goto err_out; if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ) goto err_out; if (tb[TCA_ACT_COOKIE]) { int cklen = nla_len(tb[TCA_ACT_COOKIE]); if (cklen > TC_COOKIE_MAX_SIZE) goto err_out; cookie = nla_memdup_cookie(tb); if (!cookie) { err = -ENOMEM; goto err_out; } } } else { err = -EINVAL; if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ) goto err_out; } a_o = tc_lookup_action_n(act_name); if (a_o == NULL) { #ifdef CONFIG_MODULES rtnl_unlock(); request_module("act_%s", act_name); rtnl_lock(); a_o = tc_lookup_action_n(act_name); /* We dropped the RTNL semaphore in order to * perform the module load. So, even if we * succeeded in loading the module we have to * tell the caller to replay the request. We * indicate this using -EAGAIN. */ if (a_o != NULL) { err = -EAGAIN; goto err_mod; } #endif err = -ENOENT; goto err_out; } /* backward compatibility for policer */ if (name == NULL) err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, ovr, bind); else err = a_o->