sch_api.c 46.5 KB
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/*
 * net/sched/sch_api.c	Packet scheduler 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.
 *
 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 *
 * Fixes:
 *
 * Rani Assaf <rani@magic.metawire.com> :980802: JIFFIES and CPU clock sources are repaired.
 * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support
 * Jamal Hadi Salim <hadi@nortelnetworks.com>: 990601: ingress support
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/skbuff.h>
#include <linux/init.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/kmod.h>
#include <linux/list.h>
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#include <linux/hrtimer.h>
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#include <linux/lockdep.h>
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#include <linux/slab.h>
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#include <linux/hashtable.h>
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#include <net/net_namespace.h>
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#include <net/sock.h>
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#include <net/netlink.h>
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#include <net/pkt_sched.h>

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static int qdisc_notify(struct net *net, struct sk_buff *oskb,
			struct nlmsghdr *n, u32 clid,
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			struct Qdisc *old, struct Qdisc *new);
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static int tclass_notify(struct net *net, struct sk_buff *oskb,
			 struct nlmsghdr *n, struct Qdisc *q,
			 unsigned long cl, int event);
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/*

   Short review.
   -------------

   This file consists of two interrelated parts:

   1. queueing disciplines manager frontend.
   2. traffic classes manager frontend.

   Generally, queueing discipline ("qdisc") is a black box,
   which is able to enqueue packets and to dequeue them (when
   device is ready to send something) in order and at times
   determined by algorithm hidden in it.

   qdisc's are divided to two categories:
   - "queues", which have no internal structure visible from outside.
   - "schedulers", which split all the packets to "traffic classes",
     using "packet classifiers" (look at cls_api.c)

   In turn, classes may have child qdiscs (as rule, queues)
   attached to them etc. etc. etc.

   The goal of the routines in this file is to translate
   information supplied by user in the form of handles
   to more intelligible for kernel form, to make some sanity
   checks and part of work, which is common to all qdiscs
   and to provide rtnetlink notifications.

   All real intelligent work is done inside qdisc modules.



   Every discipline has two major routines: enqueue and dequeue.

   ---dequeue

   dequeue usually returns a skb to send. It is allowed to return NULL,
   but it does not mean that queue is empty, it just means that
   discipline does not want to send anything this time.
   Queue is really empty if q->q.qlen == 0.
   For complicated disciplines with multiple queues q->q is not
   real packet queue, but however q->q.qlen must be valid.

   ---enqueue

   enqueue returns 0, if packet was enqueued successfully.
   If packet (this one or another one) was dropped, it returns
   not zero error code.
   NET_XMIT_DROP 	- this packet dropped
     Expected action: do not backoff, but wait until queue will clear.
   NET_XMIT_CN	 	- probably this packet enqueued, but another one dropped.
     Expected action: backoff or ignore

   Auxiliary routines:

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   ---peek

   like dequeue but without removing a packet from the queue

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   ---reset

   returns qdisc to initial state: purge all buffers, clear all
   timers, counters (except for statistics) etc.

   ---init

   initializes newly created qdisc.

   ---destroy

   destroys resources allocated by init and during lifetime of qdisc.

   ---change

   changes qdisc parameters.
 */

/* Protects list of registered TC modules. It is pure SMP lock. */
static DEFINE_RWLOCK(qdisc_mod_lock);


/************************************************
 *	Queueing disciplines manipulation.	*
 ************************************************/


/* The list of all installed queueing disciplines. */

static struct Qdisc_ops *qdisc_base;

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/* Register/unregister queueing discipline */
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int register_qdisc(struct Qdisc_ops *qops)
{
	struct Qdisc_ops *q, **qp;
	int rc = -EEXIST;

	write_lock(&qdisc_mod_lock);
	for (qp = &qdisc_base; (q = *qp) != NULL; qp = &q->next)
		if (!strcmp(qops->id, q->id))
			goto out;

	if (qops->enqueue == NULL)
		qops->enqueue = noop_qdisc_ops.enqueue;
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	if (qops->peek == NULL) {
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		if (qops->dequeue == NULL)
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			qops->peek = noop_qdisc_ops.peek;
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		else
			goto out_einval;
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	}
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	if (qops->dequeue == NULL)
		qops->dequeue = noop_qdisc_ops.dequeue;

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	if (qops->cl_ops) {
		const struct Qdisc_class_ops *cops = qops->cl_ops;

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		if (!(cops->get && cops->put && cops->walk && cops->leaf))
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			goto out_einval;

		if (cops->tcf_chain && !(cops->bind_tcf && cops->unbind_tcf))
			goto out_einval;
	}

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	qops->next = NULL;
	*qp = qops;
	rc = 0;
out:
	write_unlock(&qdisc_mod_lock);
	return rc;
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out_einval:
	rc = -EINVAL;
	goto out;
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}
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EXPORT_SYMBOL(register_qdisc);
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int unregister_qdisc(struct Qdisc_ops *qops)
{
	struct Qdisc_ops *q, **qp;
	int err = -ENOENT;

	write_lock(&qdisc_mod_lock);
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	for (qp = &qdisc_base; (q = *qp) != NULL; qp = &q->next)
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		if (q == qops)
			break;
	if (q) {
		*qp = q->next;
		q->next = NULL;
		err = 0;
	}
	write_unlock(&qdisc_mod_lock);
	return err;
}
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EXPORT_SYMBOL(unregister_qdisc);
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/* Get default qdisc if not otherwise specified */
void qdisc_get_default(char *name, size_t len)
{
	read_lock(&qdisc_mod_lock);
	strlcpy(name, default_qdisc_ops->id, len);
	read_unlock(&qdisc_mod_lock);
}

static struct Qdisc_ops *qdisc_lookup_default(const char *name)
{
	struct Qdisc_ops *q = NULL;

	for (q = qdisc_base; q; q = q->next) {
		if (!strcmp(name, q->id)) {
			if (!try_module_get(q->owner))
				q = NULL;
			break;
		}
	}

	return q;
}

/* Set new default qdisc to use */
int qdisc_set_default(const char *name)
{
	const struct Qdisc_ops *ops;

	if (!capable(CAP_NET_ADMIN))
		return -EPERM;

	write_lock(&qdisc_mod_lock);
	ops = qdisc_lookup_default(name);
	if (!ops) {
		/* Not found, drop lock and try to load module */
		write_unlock(&qdisc_mod_lock);
		request_module("sch_%s", name);
		write_lock(&qdisc_mod_lock);

		ops = qdisc_lookup_default(name);
	}

	if (ops) {
		/* Set new default */
		module_put(default_qdisc_ops->owner);
		default_qdisc_ops = ops;
	}
	write_unlock(&qdisc_mod_lock);

	return ops ? 0 : -ENOENT;
}

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#ifdef CONFIG_NET_SCH_DEFAULT
/* Set default value from kernel config */
static int __init sch_default_qdisc(void)
{
	return qdisc_set_default(CONFIG_DEFAULT_NET_SCH);
}
late_initcall(sch_default_qdisc);
#endif

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/* We know handle. Find qdisc among all qdisc's attached to device
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 * (root qdisc, all its children, children of children etc.)
 * Note: caller either uses rtnl or rcu_read_lock()
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 */

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static struct Qdisc *qdisc_match_from_root(struct Qdisc *root, u32 handle)
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{
	struct Qdisc *q;

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	if (!qdisc_dev(root))
		return (root->handle == handle ? root : NULL);

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	if (!(root->flags & TCQ_F_BUILTIN) &&
	    root->handle == handle)
		return root;

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	hash_for_each_possible_rcu(qdisc_dev(root)->qdisc_hash, q, hash, handle) {
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		if (q->handle == handle)
			return q;
	}
	return NULL;
}

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void qdisc_hash_add(struct Qdisc *q, bool invisible)
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{
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	if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) {
		struct Qdisc *root = qdisc_dev(q)->qdisc;
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		WARN_ON_ONCE(root == &noop_qdisc);
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		ASSERT_RTNL();
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		hash_add_rcu(qdisc_dev(q)->qdisc_hash, &q->hash, q->handle);
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		if (invisible)
			q->flags |= TCQ_F_INVISIBLE;
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	}
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}
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EXPORT_SYMBOL(qdisc_hash_add);
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void qdisc_hash_del(struct Qdisc *q)
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{
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	if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) {
		ASSERT_RTNL();
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		hash_del_rcu(&q->hash);
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	}
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}
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EXPORT_SYMBOL(qdisc_hash_del);
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struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle)
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{
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	struct Qdisc *q;

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	q = qdisc_match_from_root(dev->qdisc, handle);
	if (q)
		goto out;
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	if (dev_ingress_queue(dev))
		q = qdisc_match_from_root(
			dev_ingress_queue(dev)->qdisc_sleeping,
			handle);
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out:
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	return q;
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}

static struct Qdisc *qdisc_leaf(struct Qdisc *p, u32 classid)
{
	unsigned long cl;
	struct Qdisc *leaf;
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	const struct Qdisc_class_ops *cops = p->ops->cl_ops;
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	if (cops == NULL)
		return NULL;
	cl = cops->get(p, classid);

	if (cl == 0)
		return NULL;
	leaf = cops->leaf(p, cl);
	cops->put(p, cl);
	return leaf;
}

/* Find queueing discipline by name */

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static struct Qdisc_ops *qdisc_lookup_ops(struct nlattr *kind)
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{
	struct Qdisc_ops *q = NULL;

	if (kind) {
		read_lock(&qdisc_mod_lock);
		for (q = qdisc_base; q; q = q->next) {
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			if (nla_strcmp(kind, q->id) == 0) {
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				if (!try_module_get(q->owner))
					q = NULL;
				break;
			}
		}
		read_unlock(&qdisc_mod_lock);
	}
	return q;
}

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/* The linklayer setting were not transferred from iproute2, in older
 * versions, and the rate tables lookup systems have been dropped in
 * the kernel. To keep backward compatible with older iproute2 tc
 * utils, we detect the linklayer setting by detecting if the rate
 * table were modified.
 *
 * For linklayer ATM table entries, the rate table will be aligned to
 * 48 bytes, thus some table entries will contain the same value.  The
 * mpu (min packet unit) is also encoded into the old rate table, thus
 * starting from the mpu, we find low and high table entries for
 * mapping this cell.  If these entries contain the same value, when
 * the rate tables have been modified for linklayer ATM.
 *
 * This is done by rounding mpu to the nearest 48 bytes cell/entry,
 * and then roundup to the next cell, calc the table entry one below,
 * and compare.
 */
static __u8 __detect_linklayer(struct tc_ratespec *r, __u32 *rtab)
{
	int low       = roundup(r->mpu, 48);
	int high      = roundup(low+1, 48);
	int cell_low  = low >> r->cell_log;
	int cell_high = (high >> r->cell_log) - 1;

	/* rtab is too inaccurate at rates > 100Mbit/s */
	if ((r->rate > (100000000/8)) || (rtab[0] == 0)) {
		pr_debug("TC linklayer: Giving up ATM detection\n");
		return TC_LINKLAYER_ETHERNET;
	}

	if ((cell_high > cell_low) && (cell_high < 256)
	    && (rtab[cell_low] == rtab[cell_high])) {
		pr_debug("TC linklayer: Detected ATM, low(%d)=high(%d)=%u\n",
			 cell_low, cell_high, rtab[cell_high]);
		return TC_LINKLAYER_ATM;
	}
	return TC_LINKLAYER_ETHERNET;
}

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static struct qdisc_rate_table *qdisc_rtab_list;

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struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r,
					struct nlattr *tab)
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{
	struct qdisc_rate_table *rtab;

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	if (tab == NULL || r->rate == 0 || r->cell_log == 0 ||
	    nla_len(tab) != TC_RTAB_SIZE)
		return NULL;

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	for (rtab = qdisc_rtab_list; rtab; rtab = rtab->next) {
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		if (!memcmp(&rtab->rate, r, sizeof(struct tc_ratespec)) &&
		    !memcmp(&rtab->data, nla_data(tab), 1024)) {
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			rtab->refcnt++;
			return rtab;
		}
	}

	rtab = kmalloc(sizeof(*rtab), GFP_KERNEL);
	if (rtab) {
		rtab->rate = *r;
		rtab->refcnt = 1;
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		memcpy(rtab->data, nla_data(tab), 1024);
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		if (r->linklayer == TC_LINKLAYER_UNAWARE)
			r->linklayer = __detect_linklayer(r, rtab->data);
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		rtab->next = qdisc_rtab_list;
		qdisc_rtab_list = rtab;
	}
	return rtab;
}
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EXPORT_SYMBOL(qdisc_get_rtab);
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void qdisc_put_rtab(struct qdisc_rate_table *tab)
{
	struct qdisc_rate_table *rtab, **rtabp;

	if (!tab || --tab->refcnt)
		return;

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	for (rtabp = &qdisc_rtab_list;
	     (rtab = *rtabp) != NULL;
	     rtabp = &rtab->next) {
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		if (rtab == tab) {
			*rtabp = rtab->next;
			kfree(rtab);
			return;
		}
	}
}
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EXPORT_SYMBOL(qdisc_put_rtab);
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static LIST_HEAD(qdisc_stab_list);

static const struct nla_policy stab_policy[TCA_STAB_MAX + 1] = {
	[TCA_STAB_BASE]	= { .len = sizeof(struct tc_sizespec) },
	[TCA_STAB_DATA] = { .type = NLA_BINARY },
};

static struct qdisc_size_table *qdisc_get_stab(struct nlattr *opt)
{
	struct nlattr *tb[TCA_STAB_MAX + 1];
	struct qdisc_size_table *stab;
	struct tc_sizespec *s;
	unsigned int tsize = 0;
	u16 *tab = NULL;
	int err;

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	err = nla_parse_nested(tb, TCA_STAB_MAX, opt, stab_policy, NULL);
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	if (err < 0)
		return ERR_PTR(err);
	if (!tb[TCA_STAB_BASE])
		return ERR_PTR(-EINVAL);

	s = nla_data(tb[TCA_STAB_BASE]);

	if (s->tsize > 0) {
		if (!tb[TCA_STAB_DATA])
			return ERR_PTR(-EINVAL);
		tab = nla_data(tb[TCA_STAB_DATA]);
		tsize = nla_len(tb[TCA_STAB_DATA]) / sizeof(u16);
	}

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	if (tsize != s->tsize || (!tab && tsize > 0))
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		return ERR_PTR(-EINVAL);

	list_for_each_entry(stab, &qdisc_stab_list, list) {
		if (memcmp(&stab->szopts, s, sizeof(*s)))
			continue;
		if (tsize > 0 && memcmp(stab->data, tab, tsize * sizeof(u16)))
			continue;
		stab->refcnt++;
		return stab;
	}

	stab = kmalloc(sizeof(*stab) + tsize * sizeof(u16), GFP_KERNEL);
	if (!stab)
		return ERR_PTR(-ENOMEM);

	stab->refcnt = 1;
	stab->szopts = *s;
	if (tsize > 0)
		memcpy(stab->data, tab, tsize * sizeof(u16));

	list_add_tail(&stab->list, &qdisc_stab_list);

	return stab;
}

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static void stab_kfree_rcu(struct rcu_head *head)
{
	kfree(container_of(head, struct qdisc_size_table, rcu));
}

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void qdisc_put_stab(struct qdisc_size_table *tab)
{
	if (!tab)
		return;

	if (--tab->refcnt == 0) {
		list_del(&tab->list);
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		call_rcu_bh(&tab->rcu, stab_kfree_rcu);
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	}
}
EXPORT_SYMBOL(qdisc_put_stab);

static int qdisc_dump_stab(struct sk_buff *skb, struct qdisc_size_table *stab)
{
	struct nlattr *nest;

	nest = nla_nest_start(skb, TCA_STAB);
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	if (nest == NULL)
		goto nla_put_failure;
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	if (nla_put(skb, TCA_STAB_BASE, sizeof(stab->szopts), &stab->szopts))
		goto nla_put_failure;
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	nla_nest_end(skb, nest);

	return skb->len;

nla_put_failure:
	return -1;
}

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void __qdisc_calculate_pkt_len(struct sk_buff *skb,
			       const struct qdisc_size_table *stab)
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{
	int pkt_len, slot;

	pkt_len = skb->len + stab->szopts.overhead;
	if (unlikely(!stab->szopts.tsize))
		goto out;

	slot = pkt_len + stab->szopts.cell_align;
	if (unlikely(slot < 0))
		slot = 0;

	slot >>= stab->szopts.cell_log;
	if (likely(slot < stab->szopts.tsize))
		pkt_len = stab->data[slot];
	else
		pkt_len = stab->data[stab->szopts.tsize - 1] *
				(slot / stab->szopts.tsize) +
				stab->data[slot % stab->szopts.tsize];

	pkt_len <<= stab->szopts.size_log;
out:
	if (unlikely(pkt_len < 1))
		pkt_len = 1;
	qdisc_skb_cb(skb)->pkt_len = pkt_len;
}
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EXPORT_SYMBOL(__qdisc_calculate_pkt_len);
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void qdisc_warn_nonwc(const char *txt, struct Qdisc *qdisc)
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{
	if (!(qdisc->flags & TCQ_F_WARN_NONWC)) {
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		pr_warn("%s: %s qdisc %X: is non-work-conserving?\n",
			txt, qdisc->ops->id, qdisc->handle >> 16);
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		qdisc->flags |= TCQ_F_WARN_NONWC;
	}
}
EXPORT_SYMBOL(qdisc_warn_nonwc);

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static enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer)
{
	struct qdisc_watchdog *wd = container_of(timer, struct qdisc_watchdog,
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						 timer);
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	rcu_read_lock();
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	__netif_schedule(qdisc_root(wd->qdisc));
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	rcu_read_unlock();
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	return HRTIMER_NORESTART;
}

void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc)
{
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	hrtimer_init(&wd->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED);
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	wd->timer.function = qdisc_watchdog;
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	wd->qdisc = qdisc;
}
EXPORT_SYMBOL(qdisc_watchdog_init);

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void qdisc_watchdog_schedule_ns(struct qdisc_watchdog *wd, u64 expires)
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{
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	if (test_bit(__QDISC_STATE_DEACTIVATED,
		     &qdisc_root_sleeping(wd->qdisc)->state))
		return;

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	if (wd->last_expires == expires)
		return;

	wd->last_expires = expires;
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	hrtimer_start(&wd->timer,
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		      ns_to_ktime(expires),
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		      HRTIMER_MODE_ABS_PINNED);
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}
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EXPORT_SYMBOL(qdisc_watchdog_schedule_ns);
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void qdisc_watchdog_cancel(struct qdisc_watchdog *wd)
{
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	hrtimer_cancel(&wd->timer);
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}
EXPORT_SYMBOL(qdisc_watchdog_cancel);
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static struct hlist_head *qdisc_class_hash_alloc(unsigned int n)
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{
	unsigned int size = n * sizeof(struct hlist_head), i;
	struct hlist_head *h;

	if (size <= PAGE_SIZE)
		h = kmalloc(size, GFP_KERNEL);
	else
		h = (struct hlist_head *)
			__get_free_pages(GFP_KERNEL, get_order(size));

	if (h != NULL) {
		for (i = 0; i < n; i++)
			INIT_HLIST_HEAD(&h[i]);
	}
	return h;
}

static void qdisc_class_hash_free(struct hlist_head *h, unsigned int n)
{
	unsigned int size = n * sizeof(struct hlist_head);

	if (size <= PAGE_SIZE)
		kfree(h);
	else
		free_pages((unsigned long)h, get_order(size));
}

void qdisc_class_hash_grow(struct Qdisc *sch, struct Qdisc_class_hash *clhash)
{
	struct Qdisc_class_common *cl;
656
	struct hlist_node *next;
657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674
	struct hlist_head *nhash, *ohash;
	unsigned int nsize, nmask, osize;
	unsigned int i, h;

	/* Rehash when load factor exceeds 0.75 */
	if (clhash->hashelems * 4 <= clhash->hashsize * 3)
		return;
	nsize = clhash->hashsize * 2;
	nmask = nsize - 1;
	nhash = qdisc_class_hash_alloc(nsize);
	if (nhash == NULL)
		return;

	ohash = clhash->hash;
	osize = clhash->hashsize;

	sch_tree_lock(sch);
	for (i = 0; i < osize; i++) {
675
		hlist_for_each_entry_safe(cl, next, &ohash[i], hnode) {
676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728
			h = qdisc_class_hash(cl->classid, nmask);
			hlist_add_head(&cl->hnode, &nhash[h]);
		}
	}
	clhash->hash     = nhash;
	clhash->hashsize = nsize;
	clhash->hashmask = nmask;
	sch_tree_unlock(sch);

	qdisc_class_hash_free(ohash, osize);
}
EXPORT_SYMBOL(qdisc_class_hash_grow);

int qdisc_class_hash_init(struct Qdisc_class_hash *clhash)
{
	unsigned int size = 4;

	clhash->hash = qdisc_class_hash_alloc(size);
	if (clhash->hash == NULL)
		return -ENOMEM;
	clhash->hashsize  = size;
	clhash->hashmask  = size - 1;
	clhash->hashelems = 0;
	return 0;
}
EXPORT_SYMBOL(qdisc_class_hash_init);

void qdisc_class_hash_destroy(struct Qdisc_class_hash *clhash)
{
	qdisc_class_hash_free(clhash->hash, clhash->hashsize);
}
EXPORT_SYMBOL(qdisc_class_hash_destroy);

void qdisc_class_hash_insert(struct Qdisc_class_hash *clhash,
			     struct Qdisc_class_common *cl)
{
	unsigned int h;

	INIT_HLIST_NODE(&cl->hnode);
	h = qdisc_class_hash(cl->classid, clhash->hashmask);
	hlist_add_head(&cl->hnode, &clhash->hash[h]);
	clhash->hashelems++;
}
EXPORT_SYMBOL(qdisc_class_hash_insert);

void qdisc_class_hash_remove(struct Qdisc_class_hash *clhash,
			     struct Qdisc_class_common *cl)
{
	hlist_del(&cl->hnode);
	clhash->hashelems--;
}
EXPORT_SYMBOL(qdisc_class_hash_remove);

729 730 731
/* Allocate an unique handle from space managed by kernel
 * Possible range is [8000-FFFF]:0000 (0x8000 values)
 */
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Linus Torvalds 已提交
732 733
static u32 qdisc_alloc_handle(struct net_device *dev)
{
734
	int i = 0x8000;
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735 736 737 738 739 740
	static u32 autohandle = TC_H_MAKE(0x80000000U, 0);

	do {
		autohandle += TC_H_MAKE(0x10000U, 0);
		if (autohandle == TC_H_MAKE(TC_H_ROOT, 0))
			autohandle = TC_H_MAKE(0x80000000U, 0);
741 742 743 744
		if (!qdisc_lookup(dev, autohandle))
			return autohandle;
		cond_resched();
	} while	(--i > 0);
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Linus Torvalds 已提交
745

746
	return 0;
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747 748
}

749 750
void qdisc_tree_reduce_backlog(struct Qdisc *sch, unsigned int n,
			       unsigned int len)
751
{
752
	const struct Qdisc_class_ops *cops;
753 754
	unsigned long cl;
	u32 parentid;
755
	int drops;
756

757
	if (n == 0 && len == 0)
758
		return;
759
	drops = max_t(int, n, 0);
760
	rcu_read_lock();
761
	while ((parentid = sch->parent)) {
762
		if (TC_H_MAJ(parentid) == TC_H_MAJ(TC_H_INGRESS))
763
			break;
764

765 766 767
		if (sch->flags & TCQ_F_NOPARENT)
			break;
		/* TODO: perform the search on a per txq basis */
768
		sch = qdisc_lookup(qdisc_dev(sch), TC_H_MAJ(parentid));
769
		if (sch == NULL) {
770 771
			WARN_ON_ONCE(parentid != TC_H_ROOT);
			break;
772
		}
773 774 775 776 777 778 779
		cops = sch->ops->cl_ops;
		if (cops->qlen_notify) {
			cl = cops->get(sch, parentid);
			cops->qlen_notify(sch, cl);
			cops->put(sch, cl);
		}
		sch->q.qlen -= n;
780
		sch->qstats.backlog -= len;
781
		__qdisc_qstats_drop(sch, drops);
782
	}
783
	rcu_read_unlock();
784
}
785
EXPORT_SYMBOL(qdisc_tree_reduce_backlog);
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Linus Torvalds 已提交
786

787 788
static void notify_and_destroy(struct net *net, struct sk_buff *skb,
			       struct nlmsghdr *n, u32 clid,
789 790 791
			       struct Qdisc *old, struct Qdisc *new)
{
	if (new || old)
792
		qdisc_notify(net, skb, n, clid, old, new);
L
Linus Torvalds 已提交
793

794
	if (old)
795 796 797 798 799 800 801 802 803 804
		qdisc_destroy(old);
}

/* Graft qdisc "new" to class "classid" of qdisc "parent" or
 * to device "dev".
 *
 * When appropriate send a netlink notification using 'skb'
 * and "n".
 *
 * On success, destroy old qdisc.
L
Linus Torvalds 已提交
805 806 807
 */

static int qdisc_graft(struct net_device *dev, struct Qdisc *parent,
808 809
		       struct sk_buff *skb, struct nlmsghdr *n, u32 classid,
		       struct Qdisc *new, struct Qdisc *old)
L
Linus Torvalds 已提交
810
{
811
	struct Qdisc *q = old;
812
	struct net *net = dev_net(dev);
L
Linus Torvalds 已提交
813 814
	int err = 0;

815
	if (parent == NULL) {
816 817 818 819
		unsigned int i, num_q, ingress;

		ingress = 0;
		num_q = dev->num_tx_queues;
820 821
		if ((q && q->flags & TCQ_F_INGRESS) ||
		    (new && new->flags & TCQ_F_INGRESS)) {
822 823
			num_q = 1;
			ingress = 1;
824 825
			if (!dev_ingress_queue(dev))
				return -ENOENT;
826 827 828 829 830
		}

		if (dev->flags & IFF_UP)
			dev_deactivate(dev);

831 832
		if (new && new->ops->attach)
			goto skip;
833

834
		for (i = 0; i < num_q; i++) {
835
			struct netdev_queue *dev_queue = dev_ingress_queue(dev);
836 837 838 839

			if (!ingress)
				dev_queue = netdev_get_tx_queue(dev, i);

840 841 842 843
			old = dev_graft_qdisc(dev_queue, new);
			if (new && i > 0)
				atomic_inc(&new->refcnt);

844 845
			if (!ingress)
				qdisc_destroy(old);
L
Linus Torvalds 已提交
846
		}
847

848
skip:
849
		if (!ingress) {
850 851
			notify_and_destroy(net, skb, n, classid,
					   dev->qdisc, new);
852 853 854
			if (new && !new->ops->attach)
				atomic_inc(&new->refcnt);
			dev->qdisc = new ? : &noop_qdisc;
855 856 857

			if (new && new->ops->attach)
				new->ops->attach(new);
858
		} else {
859
			notify_and_destroy(net, skb, n, classid, old, new);
860
		}
861

862 863
		if (dev->flags & IFF_UP)
			dev_activate(dev);
L
Linus Torvalds 已提交
864
	} else {
865
		const struct Qdisc_class_ops *cops = parent->ops->cl_ops;
L
Linus Torvalds 已提交
866

867 868
		err = -EOPNOTSUPP;
		if (cops && cops->graft) {
L
Linus Torvalds 已提交
869 870
			unsigned long cl = cops->get(parent, classid);
			if (cl) {
871
				err = cops->graft(parent, cl, new, &old);
L
Linus Torvalds 已提交
872
				cops->put(parent, cl);
873 874
			} else
				err = -ENOENT;
L
Linus Torvalds 已提交
875
		}
876
		if (!err)
877
			notify_and_destroy(net, skb, n, classid, old, new);
L
Linus Torvalds 已提交
878 879 880 881
	}
	return err;
}

882 883 884 885
/* lockdep annotation is needed for ingress; egress gets it only for name */
static struct lock_class_key qdisc_tx_lock;
static struct lock_class_key qdisc_rx_lock;

L
Linus Torvalds 已提交
886 887 888 889 890 891
/*
   Allocate and initialize new qdisc.

   Parameters are passed via opt.
 */

892 893 894 895
static struct Qdisc *qdisc_create(struct net_device *dev,
				  struct netdev_queue *dev_queue,
				  struct Qdisc *p, u32 parent, u32 handle,
				  struct nlattr **tca, int *errp)
L
Linus Torvalds 已提交
896 897
{
	int err;
898
	struct nlattr *kind = tca[TCA_KIND];
L
Linus Torvalds 已提交
899 900
	struct Qdisc *sch;
	struct Qdisc_ops *ops;
901
	struct qdisc_size_table *stab;
L
Linus Torvalds 已提交
902 903

	ops = qdisc_lookup_ops(kind);
904
#ifdef CONFIG_MODULES
L
Linus Torvalds 已提交
905 906
	if (ops == NULL && kind != NULL) {
		char name[IFNAMSIZ];
907
		if (nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) {
L
Linus Torvalds 已提交
908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931
			/* 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.
			 * We replay the request because the device may
			 * go away in the mean time.
			 */
			rtnl_unlock();
			request_module("sch_%s", name);
			rtnl_lock();
			ops = qdisc_lookup_ops(kind);
			if (ops != NULL) {
				/* We will try again qdisc_lookup_ops,
				 * so don't keep a reference.
				 */
				module_put(ops->owner);
				err = -EAGAIN;
				goto err_out;
			}
		}
	}
#endif

932
	err = -ENOENT;
L
Linus Torvalds 已提交
933 934 935
	if (ops == NULL)
		goto err_out;

936
	sch = qdisc_alloc(dev_queue, ops);
937 938
	if (IS_ERR(sch)) {
		err = PTR_ERR(sch);
L
Linus Torvalds 已提交
939
		goto err_out2;
940
	}
L
Linus Torvalds 已提交
941

942 943
	sch->parent = parent;

944
	if (handle == TC_H_INGRESS) {
L
Linus Torvalds 已提交
945
		sch->flags |= TCQ_F_INGRESS;
946
		handle = TC_H_MAKE(TC_H_INGRESS, 0);
947
		lockdep_set_class(qdisc_lock(sch), &qdisc_rx_lock);
948 949 950 951 952 953 954
	} else {
		if (handle == 0) {
			handle = qdisc_alloc_handle(dev);
			err = -ENOMEM;
			if (handle == 0)
				goto err_out3;
		}
955
		lockdep_set_class(qdisc_lock(sch), &qdisc_tx_lock);
956
		if (!netif_is_multiqueue(dev))
957
			sch->flags |= TCQ_F_ONETXQUEUE;
L
Linus Torvalds 已提交
958 959
	}

960
	sch->handle = handle;
L
Linus Torvalds 已提交
961

962 963 964 965 966 967 968 969 970 971 972
	/* This exist to keep backward compatible with a userspace
	 * loophole, what allowed userspace to get IFF_NO_QUEUE
	 * facility on older kernels by setting tx_queue_len=0 (prior
	 * to qdisc init), and then forgot to reinit tx_queue_len
	 * before again attaching a qdisc.
	 */
	if ((dev->priv_flags & IFF_NO_QUEUE) && (dev->tx_queue_len == 0)) {
		dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
		netdev_info(dev, "Caught tx_queue_len zero misconfig\n");
	}

973
	if (!ops->init || (err = ops->init(sch, tca[TCA_OPTIONS])) == 0) {
974 975
		if (qdisc_is_percpu_stats(sch)) {
			sch->cpu_bstats =
976
				netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu);
977 978
			if (!sch->cpu_bstats)
				goto err_out4;
979 980 981 982

			sch->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
			if (!sch->cpu_qstats)
				goto err_out4;
983 984
		}

985 986 987 988
		if (tca[TCA_STAB]) {
			stab = qdisc_get_stab(tca[TCA_STAB]);
			if (IS_ERR(stab)) {
				err = PTR_ERR(stab);
989
				goto err_out4;
990
			}
991
			rcu_assign_pointer(sch->stab, stab);
992
		}
993
		if (tca[TCA_RATE]) {
994
			seqcount_t *running;
995

996 997 998 999
			err = -EOPNOTSUPP;
			if (sch->flags & TCQ_F_MQROOT)
				goto err_out4;

1000
			if ((sch->parent != TC_H_ROOT) &&
1001 1002
			    !(sch->flags & TCQ_F_INGRESS) &&
			    (!p || !(p->flags & TCQ_F_MQROOT)))
1003
				running = qdisc_root_sleeping_running(sch);
1004
			else
1005
				running = &sch->running;
1006

1007 1008 1009
			err = gen_new_estimator(&sch->bstats,
						sch->cpu_bstats,
						&sch->rate_est,
1010 1011
						NULL,
						running,
1012
						tca[TCA_RATE]);
1013 1014
			if (err)
				goto err_out4;
1015
		}
1016

1017
		qdisc_hash_add(sch, false);
L
Linus Torvalds 已提交
1018 1019 1020

		return sch;
	}
1021 1022
	/* ops->init() failed, we call ->destroy() like qdisc_create_dflt() */
	ops->destroy(sch);
L
Linus Torvalds 已提交
1023 1024
err_out3:
	dev_put(dev);
1025
	kfree((char *) sch - sch->padded);
L
Linus Torvalds 已提交
1026 1027 1028 1029 1030
err_out2:
	module_put(ops->owner);
err_out:
	*errp = err;
	return NULL;
1031 1032

err_out4:
1033
	free_percpu(sch->cpu_bstats);
1034
	free_percpu(sch->cpu_qstats);
1035 1036 1037 1038
	/*
	 * Any broken qdiscs that would require a ops->reset() here?
	 * The qdisc was never in action so it shouldn't be necessary.
	 */
1039
	qdisc_put_stab(rtnl_dereference(sch->stab));
1040 1041 1042
	if (ops->destroy)
		ops->destroy(sch);
	goto err_out3;
L
Linus Torvalds 已提交
1043 1044
}

1045
static int qdisc_change(struct Qdisc *sch, struct nlattr **tca)
L
Linus Torvalds 已提交
1046
{
1047
	struct qdisc_size_table *ostab, *stab = NULL;
1048
	int err = 0;
L
Linus Torvalds 已提交
1049

1050
	if (tca[TCA_OPTIONS]) {
L
Linus Torvalds 已提交
1051 1052
		if (sch->ops->change == NULL)
			return -EINVAL;
1053
		err = sch->ops->change(sch, tca[TCA_OPTIONS]);
L
Linus Torvalds 已提交
1054 1055 1056
		if (err)
			return err;
	}
1057 1058 1059 1060 1061 1062 1063

	if (tca[TCA_STAB]) {
		stab = qdisc_get_stab(tca[TCA_STAB]);
		if (IS_ERR(stab))
			return PTR_ERR(stab);
	}

1064 1065 1066
	ostab = rtnl_dereference(sch->stab);
	rcu_assign_pointer(sch->stab, stab);
	qdisc_put_stab(ostab);
1067

1068
	if (tca[TCA_RATE]) {
1069 1070
		/* NB: ignores errors from replace_estimator
		   because change can't be undone. */
1071 1072
		if (sch->flags & TCQ_F_MQROOT)
			goto out;
1073 1074 1075
		gen_replace_estimator(&sch->bstats,
				      sch->cpu_bstats,
				      &sch->rate_est,
1076 1077
				      NULL,
				      qdisc_root_sleeping_running(sch),
1078
				      tca[TCA_RATE]);
1079 1080
	}
out:
L
Linus Torvalds 已提交
1081 1082 1083
	return 0;
}

E
Eric Dumazet 已提交
1084 1085
struct check_loop_arg {
	struct qdisc_walker	w;
L
Linus Torvalds 已提交
1086 1087 1088 1089
	struct Qdisc		*p;
	int			depth;
};

1090 1091
static int check_loop_fn(struct Qdisc *q, unsigned long cl,
			 struct qdisc_walker *w);
L
Linus Torvalds 已提交
1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111

static int check_loop(struct Qdisc *q, struct Qdisc *p, int depth)
{
	struct check_loop_arg	arg;

	if (q->ops->cl_ops == NULL)
		return 0;

	arg.w.stop = arg.w.skip = arg.w.count = 0;
	arg.w.fn = check_loop_fn;
	arg.depth = depth;
	arg.p = p;
	q->ops->cl_ops->walk(q, &arg.w);
	return arg.w.stop ? -ELOOP : 0;
}

static int
check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w)
{
	struct Qdisc *leaf;
1112
	const struct Qdisc_class_ops *cops = q->ops->cl_ops;
L
Linus Torvalds 已提交
1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127
	struct check_loop_arg *arg = (struct check_loop_arg *)w;

	leaf = cops->leaf(q, cl);
	if (leaf) {
		if (leaf == arg->p || arg->depth > 7)
			return -ELOOP;
		return check_loop(leaf, arg->p, arg->depth + 1);
	}
	return 0;
}

/*
 * Delete/get qdisc.
 */

1128
static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n)
L
Linus Torvalds 已提交
1129
{
1130
	struct net *net = sock_net(skb->sk);
1131
	struct tcmsg *tcm = nlmsg_data(n);
1132
	struct nlattr *tca[TCA_MAX + 1];
L
Linus Torvalds 已提交
1133
	struct net_device *dev;
1134
	u32 clid;
L
Linus Torvalds 已提交
1135 1136 1137 1138
	struct Qdisc *q = NULL;
	struct Qdisc *p = NULL;
	int err;

1139
	if ((n->nlmsg_type != RTM_GETQDISC) &&
1140
	    !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1141 1142
		return -EPERM;

1143
	err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL, NULL);
1144 1145 1146
	if (err < 0)
		return err;

1147 1148 1149 1150 1151
	dev = __dev_get_by_index(net, tcm->tcm_ifindex);
	if (!dev)
		return -ENODEV;

	clid = tcm->tcm_parent;
L
Linus Torvalds 已提交
1152 1153 1154
	if (clid) {
		if (clid != TC_H_ROOT) {
			if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) {
E
Eric Dumazet 已提交
1155 1156
				p = qdisc_lookup(dev, TC_H_MAJ(clid));
				if (!p)
L
Linus Torvalds 已提交
1157 1158
					return -ENOENT;
				q = qdisc_leaf(p, clid);
E
Eric Dumazet 已提交
1159 1160
			} else if (dev_ingress_queue(dev)) {
				q = dev_ingress_queue(dev)->qdisc_sleeping;
1161
			}
L
Linus Torvalds 已提交
1162
		} else {
1163
			q = dev->qdisc;
L
Linus Torvalds 已提交
1164 1165 1166 1167 1168 1169 1170
		}
		if (!q)
			return -ENOENT;

		if (tcm->tcm_handle && q->handle != tcm->tcm_handle)
			return -EINVAL;
	} else {
E
Eric Dumazet 已提交
1171 1172
		q = qdisc_lookup(dev, tcm->tcm_handle);
		if (!q)
L
Linus Torvalds 已提交
1173 1174 1175
			return -ENOENT;
	}

1176
	if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
L
Linus Torvalds 已提交
1177 1178 1179 1180 1181 1182 1183
		return -EINVAL;

	if (n->nlmsg_type == RTM_DELQDISC) {
		if (!clid)
			return -EINVAL;
		if (q->handle == 0)
			return -ENOENT;
E
Eric Dumazet 已提交
1184 1185
		err = qdisc_graft(dev, p, skb, n, clid, NULL, q);
		if (err != 0)
L
Linus Torvalds 已提交
1186 1187
			return err;
	} else {
1188
		qdisc_notify(net, skb, n, clid, NULL, q);
L
Linus Torvalds 已提交
1189 1190 1191 1192 1193
	}
	return 0;
}

/*
E
Eric Dumazet 已提交
1194
 * Create/change qdisc.
L
Linus Torvalds 已提交
1195 1196
 */

1197
static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n)
L
Linus Torvalds 已提交
1198
{
1199
	struct net *net = sock_net(skb->sk);
L
Linus Torvalds 已提交
1200
	struct tcmsg *tcm;
1201
	struct nlattr *tca[TCA_MAX + 1];
L
Linus Torvalds 已提交
1202 1203 1204 1205 1206
	struct net_device *dev;
	u32 clid;
	struct Qdisc *q, *p;
	int err;

1207
	if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1208 1209
		return -EPERM;

L
Linus Torvalds 已提交
1210 1211
replay:
	/* Reinit, just in case something touches this. */
1212
	err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL, NULL);
1213 1214 1215
	if (err < 0)
		return err;

1216
	tcm = nlmsg_data(n);
L
Linus Torvalds 已提交
1217 1218 1219
	clid = tcm->tcm_parent;
	q = p = NULL;

E
Eric Dumazet 已提交
1220 1221
	dev = __dev_get_by_index(net, tcm->tcm_ifindex);
	if (!dev)
L
Linus Torvalds 已提交
1222 1223
		return -ENODEV;

1224

L
Linus Torvalds 已提交
1225 1226 1227
	if (clid) {
		if (clid != TC_H_ROOT) {
			if (clid != TC_H_INGRESS) {
E
Eric Dumazet 已提交
1228 1229
				p = qdisc_lookup(dev, TC_H_MAJ(clid));
				if (!p)
L
Linus Torvalds 已提交
1230 1231
					return -ENOENT;
				q = qdisc_leaf(p, clid);
E
Eric Dumazet 已提交
1232 1233
			} else if (dev_ingress_queue_create(dev)) {
				q = dev_ingress_queue(dev)->qdisc_sleeping;
L
Linus Torvalds 已提交
1234 1235
			}
		} else {
1236
			q = dev->qdisc;
L
Linus Torvalds 已提交
1237 1238 1239 1240 1241 1242 1243 1244
		}

		/* It may be default qdisc, ignore it */
		if (q && q->handle == 0)
			q = NULL;

		if (!q || !tcm->tcm_handle || q->handle != tcm->tcm_handle) {
			if (tcm->tcm_handle) {
E
Eric Dumazet 已提交
1245
				if (q && !(n->nlmsg_flags & NLM_F_REPLACE))
L
Linus Torvalds 已提交
1246 1247 1248
					return -EEXIST;
				if (TC_H_MIN(tcm->tcm_handle))
					return -EINVAL;
E
Eric Dumazet 已提交
1249 1250
				q = qdisc_lookup(dev, tcm->tcm_handle);
				if (!q)
L
Linus Torvalds 已提交
1251
					goto create_n_graft;
E
Eric Dumazet 已提交
1252
				if (n->nlmsg_flags & NLM_F_EXCL)
L
Linus Torvalds 已提交
1253
					return -EEXIST;
1254
				if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
L
Linus Torvalds 已提交
1255 1256 1257 1258 1259 1260 1261
					return -EINVAL;
				if (q == p ||
				    (p && check_loop(q, p, 0)))
					return -ELOOP;
				atomic_inc(&q->refcnt);
				goto graft;
			} else {
E
Eric Dumazet 已提交
1262
				if (!q)
L
Linus Torvalds 已提交
1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283
					goto create_n_graft;

				/* This magic test requires explanation.
				 *
				 *   We know, that some child q is already
				 *   attached to this parent and have choice:
				 *   either to change it or to create/graft new one.
				 *
				 *   1. We are allowed to create/graft only
				 *   if CREATE and REPLACE flags are set.
				 *
				 *   2. If EXCL is set, requestor wanted to say,
				 *   that qdisc tcm_handle is not expected
				 *   to exist, so that we choose create/graft too.
				 *
				 *   3. The last case is when no flags are set.
				 *   Alas, it is sort of hole in API, we
				 *   cannot decide what to do unambiguously.
				 *   For now we select create/graft, if
				 *   user gave KIND, which does not match existing.
				 */
E
Eric Dumazet 已提交
1284 1285 1286
				if ((n->nlmsg_flags & NLM_F_CREATE) &&
				    (n->nlmsg_flags & NLM_F_REPLACE) &&
				    ((n->nlmsg_flags & NLM_F_EXCL) ||
1287 1288
				     (tca[TCA_KIND] &&
				      nla_strcmp(tca[TCA_KIND], q->ops->id))))
L
Linus Torvalds 已提交
1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300
					goto create_n_graft;
			}
		}
	} else {
		if (!tcm->tcm_handle)
			return -EINVAL;
		q = qdisc_lookup(dev, tcm->tcm_handle);
	}

	/* Change qdisc parameters */
	if (q == NULL)
		return -ENOENT;
E
Eric Dumazet 已提交
1301
	if (n->nlmsg_flags & NLM_F_EXCL)
L
Linus Torvalds 已提交
1302
		return -EEXIST;
1303
	if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
L
Linus Torvalds 已提交
1304 1305 1306
		return -EINVAL;
	err = qdisc_change(q, tca);
	if (err == 0)
1307
		qdisc_notify(net, skb, n, clid, NULL, q);
L
Linus Torvalds 已提交
1308 1309 1310
	return err;

create_n_graft:
E
Eric Dumazet 已提交
1311
	if (!(n->nlmsg_flags & NLM_F_CREATE))
L
Linus Torvalds 已提交
1312
		return -ENOENT;
1313 1314 1315 1316 1317 1318 1319 1320
	if (clid == TC_H_INGRESS) {
		if (dev_ingress_queue(dev))
			q = qdisc_create(dev, dev_ingress_queue(dev), p,
					 tcm->tcm_parent, tcm->tcm_parent,
					 tca, &err);
		else
			err = -ENOENT;
	} else {
1321
		struct netdev_queue *dev_queue;
1322 1323

		if (p && p->ops->cl_ops && p->ops->cl_ops->select_queue)
1324 1325 1326 1327 1328
			dev_queue = p->ops->cl_ops->select_queue(p, tcm);
		else if (p)
			dev_queue = p->dev_queue;
		else
			dev_queue = netdev_get_tx_queue(dev, 0);
1329

1330
		q = qdisc_create(dev, dev_queue, p,
1331
				 tcm->tcm_parent, tcm->tcm_handle,
1332
				 tca, &err);
1333
	}
L
Linus Torvalds 已提交
1334 1335 1336 1337 1338 1339 1340
	if (q == NULL) {
		if (err == -EAGAIN)
			goto replay;
		return err;
	}

graft:
1341 1342 1343 1344 1345
	err = qdisc_graft(dev, p, skb, n, clid, q, NULL);
	if (err) {
		if (q)
			qdisc_destroy(q);
		return err;
L
Linus Torvalds 已提交
1346
	}
1347

L
Linus Torvalds 已提交
1348 1349 1350 1351
	return 0;
}

static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid,
1352
			 u32 portid, u32 seq, u16 flags, int event)
L
Linus Torvalds 已提交
1353
{
1354
	struct gnet_stats_basic_cpu __percpu *cpu_bstats = NULL;
1355
	struct gnet_stats_queue __percpu *cpu_qstats = NULL;
L
Linus Torvalds 已提交
1356 1357
	struct tcmsg *tcm;
	struct nlmsghdr  *nlh;
1358
	unsigned char *b = skb_tail_pointer(skb);
L
Linus Torvalds 已提交
1359
	struct gnet_dump d;
1360
	struct qdisc_size_table *stab;
1361
	__u32 qlen;
L
Linus Torvalds 已提交
1362

1363
	cond_resched();
1364
	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1365 1366 1367
	if (!nlh)
		goto out_nlmsg_trim;
	tcm = nlmsg_data(nlh);
L
Linus Torvalds 已提交
1368
	tcm->tcm_family = AF_UNSPEC;
1369 1370
	tcm->tcm__pad1 = 0;
	tcm->tcm__pad2 = 0;
1371
	tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
L
Linus Torvalds 已提交
1372 1373 1374
	tcm->tcm_parent = clid;
	tcm->tcm_handle = q->handle;
	tcm->tcm_info = atomic_read(&q->refcnt);
1375 1376
	if (nla_put_string(skb, TCA_KIND, q->ops->id))
		goto nla_put_failure;
L
Linus Torvalds 已提交
1377
	if (q->ops->dump && q->ops->dump(q, skb) < 0)
1378
		goto nla_put_failure;
1379
	qlen = q->q.qlen;
L
Linus Torvalds 已提交
1380

1381 1382
	stab = rtnl_dereference(q->stab);
	if (stab && qdisc_dump_stab(skb, stab) < 0)
1383 1384
		goto nla_put_failure;

1385
	if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
1386
					 NULL, &d, TCA_PAD) < 0)
1387
		goto nla_put_failure;
L
Linus Torvalds 已提交
1388 1389

	if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0)
1390
		goto nla_put_failure;
L
Linus Torvalds 已提交
1391

1392
	if (qdisc_is_percpu_stats(q)) {
1393
		cpu_bstats = q->cpu_bstats;
1394 1395
		cpu_qstats = q->cpu_qstats;
	}
1396

1397 1398
	if (gnet_stats_copy_basic(qdisc_root_sleeping_running(q),
				  &d, cpu_bstats, &q->bstats) < 0 ||
1399
	    gnet_stats_copy_rate_est(&d, &q->rate_est) < 0 ||
1400
	    gnet_stats_copy_queue(&d, cpu_qstats, &q->qstats, qlen) < 0)
1401
		goto nla_put_failure;
1402

L
Linus Torvalds 已提交
1403
	if (gnet_stats_finish_copy(&d) < 0)
1404
		goto nla_put_failure;
1405

1406
	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
L
Linus Torvalds 已提交
1407 1408
	return skb->len;

1409
out_nlmsg_trim:
1410
nla_put_failure:
1411
	nlmsg_trim(skb, b);
L
Linus Torvalds 已提交
1412 1413 1414
	return -1;
}

1415
static bool tc_qdisc_dump_ignore(struct Qdisc *q, bool dump_invisible)
1416
{
1417 1418 1419 1420 1421 1422
	if (q->flags & TCQ_F_BUILTIN)
		return true;
	if ((q->flags & TCQ_F_INVISIBLE) && !dump_invisible)
		return true;

	return false;
1423 1424
}

1425 1426 1427
static int qdisc_notify(struct net *net, struct sk_buff *oskb,
			struct nlmsghdr *n, u32 clid,
			struct Qdisc *old, struct Qdisc *new)
L
Linus Torvalds 已提交
1428 1429
{
	struct sk_buff *skb;
1430
	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
L
Linus Torvalds 已提交
1431 1432 1433 1434 1435

	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
	if (!skb)
		return -ENOBUFS;

1436
	if (old && !tc_qdisc_dump_ignore(old, false)) {
1437
		if (tc_fill_qdisc(skb, old, clid, portid, n->nlmsg_seq,
E
Eric Dumazet 已提交
1438
				  0, RTM_DELQDISC) < 0)
L
Linus Torvalds 已提交
1439 1440
			goto err_out;
	}
1441
	if (new && !tc_qdisc_dump_ignore(new, false)) {
1442
		if (tc_fill_qdisc(skb, new, clid, portid, n->nlmsg_seq,
E
Eric Dumazet 已提交
1443
				  old ? NLM_F_REPLACE : 0, RTM_NEWQDISC) < 0)
L
Linus Torvalds 已提交
1444 1445 1446 1447
			goto err_out;
	}

	if (skb->len)
1448
		return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
E
Eric Dumazet 已提交
1449
				      n->nlmsg_flags & NLM_F_ECHO);
L
Linus Torvalds 已提交
1450 1451 1452 1453 1454 1455

err_out:
	kfree_skb(skb);
	return -EINVAL;
}

1456 1457
static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb,
			      struct netlink_callback *cb,
1458 1459
			      int *q_idx_p, int s_q_idx, bool recur,
			      bool dump_invisible)
1460 1461 1462
{
	int ret = 0, q_idx = *q_idx_p;
	struct Qdisc *q;
1463
	int b;
1464 1465 1466 1467 1468 1469 1470 1471

	if (!root)
		return 0;

	q = root;
	if (q_idx < s_q_idx) {
		q_idx++;
	} else {
1472
		if (!tc_qdisc_dump_ignore(q, dump_invisible) &&
1473
		    tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
1474 1475
				  cb->nlh->nlmsg_seq, NLM_F_MULTI,
				  RTM_NEWQDISC) <= 0)
1476 1477 1478
			goto done;
		q_idx++;
	}
1479

1480 1481 1482 1483 1484 1485 1486
	/* If dumping singletons, there is no qdisc_dev(root) and the singleton
	 * itself has already been dumped.
	 *
	 * If we've already dumped the top-level (ingress) qdisc above and the global
	 * qdisc hashtable, we don't want to hit it again
	 */
	if (!qdisc_dev(root) || !recur)
1487 1488
		goto out;

1489
	hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) {
1490 1491 1492 1493
		if (q_idx < s_q_idx) {
			q_idx++;
			continue;
		}
1494
		if (!tc_qdisc_dump_ignore(q, dump_invisible) &&
1495
		    tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
1496 1497
				  cb->nlh->nlmsg_seq, NLM_F_MULTI,
				  RTM_NEWQDISC) <= 0)
1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509
			goto done;
		q_idx++;
	}

out:
	*q_idx_p = q_idx;
	return ret;
done:
	ret = -1;
	goto out;
}

L
Linus Torvalds 已提交
1510 1511
static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb)
{
1512
	struct net *net = sock_net(skb->sk);
L
Linus Torvalds 已提交
1513 1514 1515
	int idx, q_idx;
	int s_idx, s_q_idx;
	struct net_device *dev;
1516 1517 1518 1519
	const struct nlmsghdr *nlh = cb->nlh;
	struct tcmsg *tcm = nlmsg_data(nlh);
	struct nlattr *tca[TCA_MAX + 1];
	int err;
L
Linus Torvalds 已提交
1520 1521 1522

	s_idx = cb->args[0];
	s_q_idx = q_idx = cb->args[1];
1523

1524
	idx = 0;
1525
	ASSERT_RTNL();
1526

1527
	err = nlmsg_parse(nlh, sizeof(*tcm), tca, TCA_MAX, NULL, NULL);
1528 1529 1530
	if (err < 0)
		return err;

1531
	for_each_netdev(net, dev) {
1532 1533
		struct netdev_queue *dev_queue;

L
Linus Torvalds 已提交
1534
		if (idx < s_idx)
1535
			goto cont;
L
Linus Torvalds 已提交
1536 1537 1538
		if (idx > s_idx)
			s_q_idx = 0;
		q_idx = 0;
1539

1540
		if (tc_dump_qdisc_root(dev->qdisc, skb, cb, &q_idx, s_q_idx,
1541
				       true, tca[TCA_DUMP_INVISIBLE]) < 0)
1542 1543
			goto done;

1544 1545 1546
		dev_queue = dev_ingress_queue(dev);
		if (dev_queue &&
		    tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb,
1547 1548
				       &q_idx, s_q_idx, false,
				       tca[TCA_DUMP_INVISIBLE]) < 0)
1549 1550
			goto done;

1551 1552
cont:
		idx++;
L
Linus Torvalds 已提交
1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569
	}

done:
	cb->args[0] = idx;
	cb->args[1] = q_idx;

	return skb->len;
}



/************************************************
 *	Traffic classes manipulation.		*
 ************************************************/



1570
static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n)
L
Linus Torvalds 已提交
1571
{
1572
	struct net *net = sock_net(skb->sk);
1573
	struct tcmsg *tcm = nlmsg_data(n);
1574
	struct nlattr *tca[TCA_MAX + 1];
L
Linus Torvalds 已提交
1575 1576
	struct net_device *dev;
	struct Qdisc *q = NULL;
1577
	const struct Qdisc_class_ops *cops;
L
Linus Torvalds 已提交
1578 1579
	unsigned long cl = 0;
	unsigned long new_cl;
1580 1581 1582
	u32 portid;
	u32 clid;
	u32 qid;
L
Linus Torvalds 已提交
1583 1584
	int err;

1585
	if ((n->nlmsg_type != RTM_GETTCLASS) &&
1586
	    !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1587 1588
		return -EPERM;

1589
	err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL, NULL);
1590 1591 1592
	if (err < 0)
		return err;

1593 1594 1595 1596
	dev = __dev_get_by_index(net, tcm->tcm_ifindex);
	if (!dev)
		return -ENODEV;

L
Linus Torvalds 已提交
1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611
	/*
	   parent == TC_H_UNSPEC - unspecified parent.
	   parent == TC_H_ROOT   - class is root, which has no parent.
	   parent == X:0	 - parent is root class.
	   parent == X:Y	 - parent is a node in hierarchy.
	   parent == 0:Y	 - parent is X:Y, where X:0 is qdisc.

	   handle == 0:0	 - generate handle from kernel pool.
	   handle == 0:Y	 - class is X:Y, where X:0 is qdisc.
	   handle == X:Y	 - clear.
	   handle == X:0	 - root class.
	 */

	/* Step 1. Determine qdisc handle X:0 */

1612 1613 1614 1615
	portid = tcm->tcm_parent;
	clid = tcm->tcm_handle;
	qid = TC_H_MAJ(clid);

1616 1617
	if (portid != TC_H_ROOT) {
		u32 qid1 = TC_H_MAJ(portid);
L
Linus Torvalds 已提交
1618 1619 1620 1621 1622 1623 1624 1625

		if (qid && qid1) {
			/* If both majors are known, they must be identical. */
			if (qid != qid1)
				return -EINVAL;
		} else if (qid1) {
			qid = qid1;
		} else if (qid == 0)
1626
			qid = dev->qdisc->handle;
L
Linus Torvalds 已提交
1627 1628

		/* Now qid is genuine qdisc handle consistent
E
Eric Dumazet 已提交
1629 1630
		 * both with parent and child.
		 *
1631
		 * TC_H_MAJ(portid) still may be unspecified, complete it now.
L
Linus Torvalds 已提交
1632
		 */
1633 1634
		if (portid)
			portid = TC_H_MAKE(qid, portid);
L
Linus Torvalds 已提交
1635 1636
	} else {
		if (qid == 0)
1637
			qid = dev->qdisc->handle;
L
Linus Torvalds 已提交
1638 1639 1640
	}

	/* OK. Locate qdisc */
E
Eric Dumazet 已提交
1641 1642
	q = qdisc_lookup(dev, qid);
	if (!q)
L
Linus Torvalds 已提交
1643 1644 1645 1646 1647 1648 1649 1650 1651
		return -ENOENT;

	/* An check that it supports classes */
	cops = q->ops->cl_ops;
	if (cops == NULL)
		return -EINVAL;

	/* Now try to get class */
	if (clid == 0) {
1652
		if (portid == TC_H_ROOT)
L
Linus Torvalds 已提交
1653 1654 1655 1656 1657 1658 1659 1660 1661
			clid = qid;
	} else
		clid = TC_H_MAKE(qid, clid);

	if (clid)
		cl = cops->get(q, clid);

	if (cl == 0) {
		err = -ENOENT;
E
Eric Dumazet 已提交
1662 1663
		if (n->nlmsg_type != RTM_NEWTCLASS ||
		    !(n->nlmsg_flags & NLM_F_CREATE))
L
Linus Torvalds 已提交
1664 1665 1666
			goto out;
	} else {
		switch (n->nlmsg_type) {
1667
		case RTM_NEWTCLASS:
L
Linus Torvalds 已提交
1668
			err = -EEXIST;
E
Eric Dumazet 已提交
1669
			if (n->nlmsg_flags & NLM_F_EXCL)
L
Linus Torvalds 已提交
1670 1671 1672
				goto out;
			break;
		case RTM_DELTCLASS:
1673 1674 1675
			err = -EOPNOTSUPP;
			if (cops->delete)
				err = cops->delete(q, cl);
L
Linus Torvalds 已提交
1676
			if (err == 0)
1677 1678
				tclass_notify(net, skb, n, q, cl,
					      RTM_DELTCLASS);
L
Linus Torvalds 已提交
1679 1680
			goto out;
		case RTM_GETTCLASS:
1681
			err = tclass_notify(net, skb, n, q, cl, RTM_NEWTCLASS);
L
Linus Torvalds 已提交
1682 1683 1684 1685 1686 1687 1688 1689
			goto out;
		default:
			err = -EINVAL;
			goto out;
		}
	}

	new_cl = cl;
1690 1691
	err = -EOPNOTSUPP;
	if (cops->change)
1692
		err = cops->change(q, clid, portid, tca, &new_cl);
L
Linus Torvalds 已提交
1693
	if (err == 0)
1694
		tclass_notify(net, skb, n, q, new_cl, RTM_NEWTCLASS);
L
Linus Torvalds 已提交
1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705

out:
	if (cl)
		cops->put(q, cl);

	return err;
}


static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q,
			  unsigned long cl,
1706
			  u32 portid, u32 seq, u16 flags, int event)
L
Linus Torvalds 已提交
1707 1708 1709
{
	struct tcmsg *tcm;
	struct nlmsghdr  *nlh;
1710
	unsigned char *b = skb_tail_pointer(skb);
L
Linus Torvalds 已提交
1711
	struct gnet_dump d;
1712
	const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops;
L
Linus Torvalds 已提交
1713

1714
	cond_resched();
1715
	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1716 1717 1718
	if (!nlh)
		goto out_nlmsg_trim;
	tcm = nlmsg_data(nlh);
L
Linus Torvalds 已提交
1719
	tcm->tcm_family = AF_UNSPEC;
1720 1721
	tcm->tcm__pad1 = 0;
	tcm->tcm__pad2 = 0;
1722
	tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
L
Linus Torvalds 已提交
1723 1724 1725
	tcm->tcm_parent = q->handle;
	tcm->tcm_handle = q->handle;
	tcm->tcm_info = 0;
1726 1727
	if (nla_put_string(skb, TCA_KIND, q->ops->id))
		goto nla_put_failure;
L
Linus Torvalds 已提交
1728
	if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0)
1729
		goto nla_put_failure;
L
Linus Torvalds 已提交
1730

1731
	if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
1732
					 NULL, &d, TCA_PAD) < 0)
1733
		goto nla_put_failure;
L
Linus Torvalds 已提交
1734 1735

	if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0)
1736
		goto nla_put_failure;
L
Linus Torvalds 已提交
1737 1738

	if (gnet_stats_finish_copy(&d) < 0)
1739
		goto nla_put_failure;
L
Linus Torvalds 已提交
1740

1741
	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
L
Linus Torvalds 已提交
1742 1743
	return skb->len;

1744
out_nlmsg_trim:
1745
nla_put_failure:
1746
	nlmsg_trim(skb, b);
L
Linus Torvalds 已提交
1747 1748 1749
	return -1;
}

1750 1751 1752
static int tclass_notify(struct net *net, struct sk_buff *oskb,
			 struct nlmsghdr *n, struct Qdisc *q,
			 unsigned long cl, int event)
L
Linus Torvalds 已提交
1753 1754
{
	struct sk_buff *skb;
1755
	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
L
Linus Torvalds 已提交
1756 1757 1758 1759 1760

	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
	if (!skb)
		return -ENOBUFS;

1761
	if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, event) < 0) {
L
Linus Torvalds 已提交
1762 1763 1764 1765
		kfree_skb(skb);
		return -EINVAL;
	}

1766
	return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
E
Eric Dumazet 已提交
1767
			      n->nlmsg_flags & NLM_F_ECHO);
L
Linus Torvalds 已提交
1768 1769
}

E
Eric Dumazet 已提交
1770 1771 1772 1773
struct qdisc_dump_args {
	struct qdisc_walker	w;
	struct sk_buff		*skb;
	struct netlink_callback	*cb;
L
Linus Torvalds 已提交
1774 1775
};

1776 1777
static int qdisc_class_dump(struct Qdisc *q, unsigned long cl,
			    struct qdisc_walker *arg)
L
Linus Torvalds 已提交
1778 1779 1780
{
	struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg;

1781
	return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).portid,
1782 1783
			      a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
			      RTM_NEWTCLASS);
L
Linus Torvalds 已提交
1784 1785
}

1786 1787 1788 1789 1790 1791
static int tc_dump_tclass_qdisc(struct Qdisc *q, struct sk_buff *skb,
				struct tcmsg *tcm, struct netlink_callback *cb,
				int *t_p, int s_t)
{
	struct qdisc_dump_args arg;

1792
	if (tc_qdisc_dump_ignore(q, false) ||
1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819
	    *t_p < s_t || !q->ops->cl_ops ||
	    (tcm->tcm_parent &&
	     TC_H_MAJ(tcm->tcm_parent) != q->handle)) {
		(*t_p)++;
		return 0;
	}
	if (*t_p > s_t)
		memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0]));
	arg.w.fn = qdisc_class_dump;
	arg.skb = skb;
	arg.cb = cb;
	arg.w.stop  = 0;
	arg.w.skip = cb->args[1];
	arg.w.count = 0;
	q->ops->cl_ops->walk(q, &arg.w);
	cb->args[1] = arg.w.count;
	if (arg.w.stop)
		return -1;
	(*t_p)++;
	return 0;
}

static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb,
			       struct tcmsg *tcm, struct netlink_callback *cb,
			       int *t_p, int s_t)
{
	struct Qdisc *q;
1820
	int b;
1821 1822 1823 1824 1825 1826 1827

	if (!root)
		return 0;

	if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0)
		return -1;

1828 1829 1830
	if (!qdisc_dev(root))
		return 0;

1831
	hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) {
1832 1833 1834 1835 1836 1837 1838
		if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0)
			return -1;
	}

	return 0;
}

L
Linus Torvalds 已提交
1839 1840
static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb)
{
1841
	struct tcmsg *tcm = nlmsg_data(cb->nlh);
1842
	struct net *net = sock_net(skb->sk);
1843
	struct netdev_queue *dev_queue;
L
Linus Torvalds 已提交
1844
	struct net_device *dev;
1845
	int t, s_t;
L
Linus Torvalds 已提交
1846

1847
	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
L
Linus Torvalds 已提交
1848
		return 0;
E
Eric Dumazet 已提交
1849 1850
	dev = dev_get_by_index(net, tcm->tcm_ifindex);
	if (!dev)
L
Linus Torvalds 已提交
1851 1852 1853 1854 1855
		return 0;

	s_t = cb->args[0];
	t = 0;

1856
	if (tc_dump_tclass_root(dev->qdisc, skb, tcm, cb, &t, s_t) < 0)
1857 1858
		goto done;

1859 1860 1861 1862
	dev_queue = dev_ingress_queue(dev);
	if (dev_queue &&
	    tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb,
				&t, s_t) < 0)
1863
		goto done;
L
Linus Torvalds 已提交
1864

1865
done:
L
Linus Torvalds 已提交
1866 1867 1868 1869 1870 1871 1872
	cb->args[0] = t;

	dev_put(dev);
	return skb->len;
}

/* Main classifier routine: scans classifier chain attached
E
Eric Dumazet 已提交
1873 1874
 * to this qdisc, (optionally) tests for protocol and asks
 * specific classifiers.
L
Linus Torvalds 已提交
1875
 */
1876 1877
int tc_classify(struct sk_buff *skb, const struct tcf_proto *tp,
		struct tcf_result *res, bool compat_mode)
1878
{
1879
	__be16 protocol = tc_skb_protocol(skb);
1880
#ifdef CONFIG_NET_CLS_ACT
1881
	const int max_reclassify_loop = 4;
1882 1883
	const struct tcf_proto *old_tp = tp;
	int limit = 0;
1884

1885 1886
reclassify:
#endif
J
John Fastabend 已提交
1887
	for (; tp; tp = rcu_dereference_bh(tp->next)) {
1888 1889
		int err;

E
Eric Dumazet 已提交
1890 1891 1892 1893
		if (tp->protocol != protocol &&
		    tp->protocol != htons(ETH_P_ALL))
			continue;

1894 1895
		err = tp->classify(skb, tp, res);
#ifdef CONFIG_NET_CLS_ACT
1896
		if (unlikely(err == TC_ACT_RECLASSIFY && !compat_mode))
1897 1898
			goto reset;
#endif
1899
		if (err >= 0)
1900 1901 1902
			return err;
	}

1903
	return TC_ACT_UNSPEC; /* signal: continue lookup */
L
Linus Torvalds 已提交
1904
#ifdef CONFIG_NET_CLS_ACT
1905
reset:
1906
	if (unlikely(limit++ >= max_reclassify_loop)) {
1907 1908 1909
		net_notice_ratelimited("%s: reclassify loop, rule prio %u, protocol %02x\n",
				       tp->q->ops->id, tp->prio & 0xffff,
				       ntohs(tp->protocol));
1910
		return TC_ACT_SHOT;
L
Linus Torvalds 已提交
1911
	}
1912 1913

	tp = old_tp;
1914
	protocol = tc_skb_protocol(skb);
1915
	goto reclassify;
1916
#endif
L
Linus Torvalds 已提交
1917
}
1918
EXPORT_SYMBOL(tc_classify);
L
Linus Torvalds 已提交
1919 1920 1921 1922 1923

#ifdef CONFIG_PROC_FS
static int psched_show(struct seq_file *seq, void *v)
{
	seq_printf(seq, "%08x %08x %08x %08x\n",
1924
		   (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1),
1925
		   1000000,
1926
		   (u32)NSEC_PER_SEC / hrtimer_resolution);
L
Linus Torvalds 已提交
1927 1928 1929 1930 1931 1932

	return 0;
}

static int psched_open(struct inode *inode, struct file *file)
{
1933
	return single_open(file, psched_show, NULL);
L
Linus Torvalds 已提交
1934 1935
}

1936
static const struct file_operations psched_fops = {
L
Linus Torvalds 已提交
1937 1938 1939 1940 1941
	.owner = THIS_MODULE,
	.open = psched_open,
	.read  = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
1942
};
1943 1944 1945 1946 1947

static int __net_init psched_net_init(struct net *net)
{
	struct proc_dir_entry *e;

1948
	e = proc_create("psched", 0, net->proc_net, &psched_fops);
1949 1950 1951 1952 1953 1954 1955 1956
	if (e == NULL)
		return -ENOMEM;

	return 0;
}

static void __net_exit psched_net_exit(struct net *net)
{
1957
	remove_proc_entry("psched", net->proc_net);
1958 1959 1960 1961 1962 1963 1964 1965 1966 1967
}
#else
static int __net_init psched_net_init(struct net *net)
{
	return 0;
}

static void __net_exit psched_net_exit(struct net *net)
{
}
L
Linus Torvalds 已提交
1968 1969
#endif

1970 1971 1972 1973 1974
static struct pernet_operations psched_net_ops = {
	.init = psched_net_init,
	.exit = psched_net_exit,
};

L
Linus Torvalds 已提交
1975 1976
static int __init pktsched_init(void)
{
1977 1978 1979 1980
	int err;

	err = register_pernet_subsys(&psched_net_ops);
	if (err) {
E
Eric Dumazet 已提交
1981
		pr_err("pktsched_init: "
1982 1983 1984 1985
		       "cannot initialize per netns operations\n");
		return err;
	}

1986
	register_qdisc(&pfifo_fast_ops);
L
Linus Torvalds 已提交
1987 1988
	register_qdisc(&pfifo_qdisc_ops);
	register_qdisc(&bfifo_qdisc_ops);
1989
	register_qdisc(&pfifo_head_drop_qdisc_ops);
1990
	register_qdisc(&mq_qdisc_ops);
1991
	register_qdisc(&noqueue_qdisc_ops);
L
Linus Torvalds 已提交
1992

1993 1994
	rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL, NULL);
	rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL, NULL);
1995 1996
	rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc,
		      NULL);
1997 1998
	rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL, NULL);
	rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL, NULL);
1999 2000
	rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass,
		      NULL);
2001

L
Linus Torvalds 已提交
2002 2003 2004 2005
	return 0;
}

subsys_initcall(pktsched_init);
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