sch_api.c 45.8 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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/* 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)
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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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	}
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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;

	err = nla_parse_nested(tb, TCA_STAB_MAX, opt, stab_policy);
	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;
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	struct hlist_node *next;
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	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++) {
664
		hlist_for_each_entry_safe(cl, next, &ohash[i], hnode) {
665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717
			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);

718 719 720
/* Allocate an unique handle from space managed by kernel
 * Possible range is [8000-FFFF]:0000 (0x8000 values)
 */
L
Linus Torvalds 已提交
721 722
static u32 qdisc_alloc_handle(struct net_device *dev)
{
723
	int i = 0x8000;
L
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724 725 726 727 728 729
	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);
730 731 732 733
		if (!qdisc_lookup(dev, autohandle))
			return autohandle;
		cond_resched();
	} while	(--i > 0);
L
Linus Torvalds 已提交
734

735
	return 0;
L
Linus Torvalds 已提交
736 737
}

738 739
void qdisc_tree_reduce_backlog(struct Qdisc *sch, unsigned int n,
			       unsigned int len)
740
{
741
	const struct Qdisc_class_ops *cops;
742 743
	unsigned long cl;
	u32 parentid;
744
	int drops;
745

746
	if (n == 0 && len == 0)
747
		return;
748
	drops = max_t(int, n, 0);
749
	rcu_read_lock();
750
	while ((parentid = sch->parent)) {
751
		if (TC_H_MAJ(parentid) == TC_H_MAJ(TC_H_INGRESS))
752
			break;
753

754 755 756
		if (sch->flags & TCQ_F_NOPARENT)
			break;
		/* TODO: perform the search on a per txq basis */
757
		sch = qdisc_lookup(qdisc_dev(sch), TC_H_MAJ(parentid));
758
		if (sch == NULL) {
759 760
			WARN_ON_ONCE(parentid != TC_H_ROOT);
			break;
761
		}
762 763 764 765 766 767 768
		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;
769
		sch->qstats.backlog -= len;
770
		__qdisc_qstats_drop(sch, drops);
771
	}
772
	rcu_read_unlock();
773
}
774
EXPORT_SYMBOL(qdisc_tree_reduce_backlog);
L
Linus Torvalds 已提交
775

776 777
static void notify_and_destroy(struct net *net, struct sk_buff *skb,
			       struct nlmsghdr *n, u32 clid,
778 779 780
			       struct Qdisc *old, struct Qdisc *new)
{
	if (new || old)
781
		qdisc_notify(net, skb, n, clid, old, new);
L
Linus Torvalds 已提交
782

783
	if (old)
784 785 786 787 788 789 790 791 792 793
		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
794 795 796
 */

static int qdisc_graft(struct net_device *dev, struct Qdisc *parent,
797 798
		       struct sk_buff *skb, struct nlmsghdr *n, u32 classid,
		       struct Qdisc *new, struct Qdisc *old)
L
Linus Torvalds 已提交
799
{
800
	struct Qdisc *q = old;
801
	struct net *net = dev_net(dev);
L
Linus Torvalds 已提交
802 803
	int err = 0;

804
	if (parent == NULL) {
805 806 807 808
		unsigned int i, num_q, ingress;

		ingress = 0;
		num_q = dev->num_tx_queues;
809 810
		if ((q && q->flags & TCQ_F_INGRESS) ||
		    (new && new->flags & TCQ_F_INGRESS)) {
811 812
			num_q = 1;
			ingress = 1;
813 814
			if (!dev_ingress_queue(dev))
				return -ENOENT;
815 816 817 818 819
		}

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

820 821
		if (new && new->ops->attach)
			goto skip;
822

823
		for (i = 0; i < num_q; i++) {
824
			struct netdev_queue *dev_queue = dev_ingress_queue(dev);
825 826 827 828

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

829 830 831 832
			old = dev_graft_qdisc(dev_queue, new);
			if (new && i > 0)
				atomic_inc(&new->refcnt);

833 834
			if (!ingress)
				qdisc_destroy(old);
L
Linus Torvalds 已提交
835
		}
836

837
skip:
838
		if (!ingress) {
839 840
			notify_and_destroy(net, skb, n, classid,
					   dev->qdisc, new);
841 842 843
			if (new && !new->ops->attach)
				atomic_inc(&new->refcnt);
			dev->qdisc = new ? : &noop_qdisc;
844 845 846

			if (new && new->ops->attach)
				new->ops->attach(new);
847
		} else {
848
			notify_and_destroy(net, skb, n, classid, old, new);
849
		}
850

851 852
		if (dev->flags & IFF_UP)
			dev_activate(dev);
L
Linus Torvalds 已提交
853
	} else {
854
		const struct Qdisc_class_ops *cops = parent->ops->cl_ops;
L
Linus Torvalds 已提交
855

856 857
		err = -EOPNOTSUPP;
		if (cops && cops->graft) {
L
Linus Torvalds 已提交
858 859
			unsigned long cl = cops->get(parent, classid);
			if (cl) {
860
				err = cops->graft(parent, cl, new, &old);
L
Linus Torvalds 已提交
861
				cops->put(parent, cl);
862 863
			} else
				err = -ENOENT;
L
Linus Torvalds 已提交
864
		}
865
		if (!err)
866
			notify_and_destroy(net, skb, n, classid, old, new);
L
Linus Torvalds 已提交
867 868 869 870
	}
	return err;
}

871 872 873 874
/* 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
875 876 877 878 879 880
/*
   Allocate and initialize new qdisc.

   Parameters are passed via opt.
 */

881 882 883 884
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
885 886
{
	int err;
887
	struct nlattr *kind = tca[TCA_KIND];
L
Linus Torvalds 已提交
888 889
	struct Qdisc *sch;
	struct Qdisc_ops *ops;
890
	struct qdisc_size_table *stab;
L
Linus Torvalds 已提交
891 892

	ops = qdisc_lookup_ops(kind);
893
#ifdef CONFIG_MODULES
L
Linus Torvalds 已提交
894 895
	if (ops == NULL && kind != NULL) {
		char name[IFNAMSIZ];
896
		if (nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) {
L
Linus Torvalds 已提交
897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920
			/* 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

921
	err = -ENOENT;
L
Linus Torvalds 已提交
922 923 924
	if (ops == NULL)
		goto err_out;

925
	sch = qdisc_alloc(dev_queue, ops);
926 927
	if (IS_ERR(sch)) {
		err = PTR_ERR(sch);
L
Linus Torvalds 已提交
928
		goto err_out2;
929
	}
L
Linus Torvalds 已提交
930

931 932
	sch->parent = parent;

933
	if (handle == TC_H_INGRESS) {
L
Linus Torvalds 已提交
934
		sch->flags |= TCQ_F_INGRESS;
935
		handle = TC_H_MAKE(TC_H_INGRESS, 0);
936
		lockdep_set_class(qdisc_lock(sch), &qdisc_rx_lock);
937 938 939 940 941 942 943
	} else {
		if (handle == 0) {
			handle = qdisc_alloc_handle(dev);
			err = -ENOMEM;
			if (handle == 0)
				goto err_out3;
		}
944
		lockdep_set_class(qdisc_lock(sch), &qdisc_tx_lock);
945
		if (!netif_is_multiqueue(dev))
946
			sch->flags |= TCQ_F_ONETXQUEUE;
L
Linus Torvalds 已提交
947 948
	}

949
	sch->handle = handle;
L
Linus Torvalds 已提交
950

951 952 953 954 955 956 957 958 959 960 961
	/* 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");
	}

962
	if (!ops->init || (err = ops->init(sch, tca[TCA_OPTIONS])) == 0) {
963 964
		if (qdisc_is_percpu_stats(sch)) {
			sch->cpu_bstats =
965
				netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu);
966 967
			if (!sch->cpu_bstats)
				goto err_out4;
968 969 970 971

			sch->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
			if (!sch->cpu_qstats)
				goto err_out4;
972 973
		}

974 975 976 977
		if (tca[TCA_STAB]) {
			stab = qdisc_get_stab(tca[TCA_STAB]);
			if (IS_ERR(stab)) {
				err = PTR_ERR(stab);
978
				goto err_out4;
979
			}
980
			rcu_assign_pointer(sch->stab, stab);
981
		}
982
		if (tca[TCA_RATE]) {
983
			seqcount_t *running;
984

985 986 987 988
			err = -EOPNOTSUPP;
			if (sch->flags & TCQ_F_MQROOT)
				goto err_out4;

989
			if ((sch->parent != TC_H_ROOT) &&
990 991
			    !(sch->flags & TCQ_F_INGRESS) &&
			    (!p || !(p->flags & TCQ_F_MQROOT)))
992
				running = qdisc_root_sleeping_running(sch);
993
			else
994
				running = &sch->running;
995

996 997 998
			err = gen_new_estimator(&sch->bstats,
						sch->cpu_bstats,
						&sch->rate_est,
999 1000
						NULL,
						running,
1001
						tca[TCA_RATE]);
1002 1003
			if (err)
				goto err_out4;
1004
		}
1005

1006
		qdisc_hash_add(sch);
L
Linus Torvalds 已提交
1007 1008 1009

		return sch;
	}
1010 1011
	/* ops->init() failed, we call ->destroy() like qdisc_create_dflt() */
	ops->destroy(sch);
L
Linus Torvalds 已提交
1012 1013
err_out3:
	dev_put(dev);
1014
	kfree((char *) sch - sch->padded);
L
Linus Torvalds 已提交
1015 1016 1017 1018 1019
err_out2:
	module_put(ops->owner);
err_out:
	*errp = err;
	return NULL;
1020 1021

err_out4:
1022
	free_percpu(sch->cpu_bstats);
1023
	free_percpu(sch->cpu_qstats);
1024 1025 1026 1027
	/*
	 * Any broken qdiscs that would require a ops->reset() here?
	 * The qdisc was never in action so it shouldn't be necessary.
	 */
1028
	qdisc_put_stab(rtnl_dereference(sch->stab));
1029 1030 1031
	if (ops->destroy)
		ops->destroy(sch);
	goto err_out3;
L
Linus Torvalds 已提交
1032 1033
}

1034
static int qdisc_change(struct Qdisc *sch, struct nlattr **tca)
L
Linus Torvalds 已提交
1035
{
1036
	struct qdisc_size_table *ostab, *stab = NULL;
1037
	int err = 0;
L
Linus Torvalds 已提交
1038

1039
	if (tca[TCA_OPTIONS]) {
L
Linus Torvalds 已提交
1040 1041
		if (sch->ops->change == NULL)
			return -EINVAL;
1042
		err = sch->ops->change(sch, tca[TCA_OPTIONS]);
L
Linus Torvalds 已提交
1043 1044 1045
		if (err)
			return err;
	}
1046 1047 1048 1049 1050 1051 1052

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

1053 1054 1055
	ostab = rtnl_dereference(sch->stab);
	rcu_assign_pointer(sch->stab, stab);
	qdisc_put_stab(ostab);
1056

1057
	if (tca[TCA_RATE]) {
1058 1059
		/* NB: ignores errors from replace_estimator
		   because change can't be undone. */
1060 1061
		if (sch->flags & TCQ_F_MQROOT)
			goto out;
1062 1063 1064
		gen_replace_estimator(&sch->bstats,
				      sch->cpu_bstats,
				      &sch->rate_est,
1065 1066
				      NULL,
				      qdisc_root_sleeping_running(sch),
1067
				      tca[TCA_RATE]);
1068 1069
	}
out:
L
Linus Torvalds 已提交
1070 1071 1072
	return 0;
}

E
Eric Dumazet 已提交
1073 1074
struct check_loop_arg {
	struct qdisc_walker	w;
L
Linus Torvalds 已提交
1075 1076 1077 1078
	struct Qdisc		*p;
	int			depth;
};

1079 1080
static int check_loop_fn(struct Qdisc *q, unsigned long cl,
			 struct qdisc_walker *w);
L
Linus Torvalds 已提交
1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100

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;
1101
	const struct Qdisc_class_ops *cops = q->ops->cl_ops;
L
Linus Torvalds 已提交
1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116
	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.
 */

1117
static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n)
L
Linus Torvalds 已提交
1118
{
1119
	struct net *net = sock_net(skb->sk);
1120
	struct tcmsg *tcm = nlmsg_data(n);
1121
	struct nlattr *tca[TCA_MAX + 1];
L
Linus Torvalds 已提交
1122
	struct net_device *dev;
1123
	u32 clid;
L
Linus Torvalds 已提交
1124 1125 1126 1127
	struct Qdisc *q = NULL;
	struct Qdisc *p = NULL;
	int err;

1128
	if ((n->nlmsg_type != RTM_GETQDISC) &&
1129
	    !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1130 1131
		return -EPERM;

1132 1133 1134 1135
	err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
	if (err < 0)
		return err;

1136 1137 1138 1139 1140
	dev = __dev_get_by_index(net, tcm->tcm_ifindex);
	if (!dev)
		return -ENODEV;

	clid = tcm->tcm_parent;
L
Linus Torvalds 已提交
1141 1142 1143
	if (clid) {
		if (clid != TC_H_ROOT) {
			if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) {
E
Eric Dumazet 已提交
1144 1145
				p = qdisc_lookup(dev, TC_H_MAJ(clid));
				if (!p)
L
Linus Torvalds 已提交
1146 1147
					return -ENOENT;
				q = qdisc_leaf(p, clid);
E
Eric Dumazet 已提交
1148 1149
			} else if (dev_ingress_queue(dev)) {
				q = dev_ingress_queue(dev)->qdisc_sleeping;
1150
			}
L
Linus Torvalds 已提交
1151
		} else {
1152
			q = dev->qdisc;
L
Linus Torvalds 已提交
1153 1154 1155 1156 1157 1158 1159
		}
		if (!q)
			return -ENOENT;

		if (tcm->tcm_handle && q->handle != tcm->tcm_handle)
			return -EINVAL;
	} else {
E
Eric Dumazet 已提交
1160 1161
		q = qdisc_lookup(dev, tcm->tcm_handle);
		if (!q)
L
Linus Torvalds 已提交
1162 1163 1164
			return -ENOENT;
	}

1165
	if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
L
Linus Torvalds 已提交
1166 1167 1168 1169 1170 1171 1172
		return -EINVAL;

	if (n->nlmsg_type == RTM_DELQDISC) {
		if (!clid)
			return -EINVAL;
		if (q->handle == 0)
			return -ENOENT;
E
Eric Dumazet 已提交
1173 1174
		err = qdisc_graft(dev, p, skb, n, clid, NULL, q);
		if (err != 0)
L
Linus Torvalds 已提交
1175 1176
			return err;
	} else {
1177
		qdisc_notify(net, skb, n, clid, NULL, q);
L
Linus Torvalds 已提交
1178 1179 1180 1181 1182
	}
	return 0;
}

/*
E
Eric Dumazet 已提交
1183
 * Create/change qdisc.
L
Linus Torvalds 已提交
1184 1185
 */

1186
static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n)
L
Linus Torvalds 已提交
1187
{
1188
	struct net *net = sock_net(skb->sk);
L
Linus Torvalds 已提交
1189
	struct tcmsg *tcm;
1190
	struct nlattr *tca[TCA_MAX + 1];
L
Linus Torvalds 已提交
1191 1192 1193 1194 1195
	struct net_device *dev;
	u32 clid;
	struct Qdisc *q, *p;
	int err;

1196
	if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1197 1198
		return -EPERM;

L
Linus Torvalds 已提交
1199 1200
replay:
	/* Reinit, just in case something touches this. */
1201 1202 1203 1204
	err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
	if (err < 0)
		return err;

1205
	tcm = nlmsg_data(n);
L
Linus Torvalds 已提交
1206 1207 1208
	clid = tcm->tcm_parent;
	q = p = NULL;

E
Eric Dumazet 已提交
1209 1210
	dev = __dev_get_by_index(net, tcm->tcm_ifindex);
	if (!dev)
L
Linus Torvalds 已提交
1211 1212
		return -ENODEV;

1213

L
Linus Torvalds 已提交
1214 1215 1216
	if (clid) {
		if (clid != TC_H_ROOT) {
			if (clid != TC_H_INGRESS) {
E
Eric Dumazet 已提交
1217 1218
				p = qdisc_lookup(dev, TC_H_MAJ(clid));
				if (!p)
L
Linus Torvalds 已提交
1219 1220
					return -ENOENT;
				q = qdisc_leaf(p, clid);
E
Eric Dumazet 已提交
1221 1222
			} else if (dev_ingress_queue_create(dev)) {
				q = dev_ingress_queue(dev)->qdisc_sleeping;
L
Linus Torvalds 已提交
1223 1224
			}
		} else {
1225
			q = dev->qdisc;
L
Linus Torvalds 已提交
1226 1227 1228 1229 1230 1231 1232 1233
		}

		/* 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
1234
				if (q && !(n->nlmsg_flags & NLM_F_REPLACE))
L
Linus Torvalds 已提交
1235 1236 1237
					return -EEXIST;
				if (TC_H_MIN(tcm->tcm_handle))
					return -EINVAL;
E
Eric Dumazet 已提交
1238 1239
				q = qdisc_lookup(dev, tcm->tcm_handle);
				if (!q)
L
Linus Torvalds 已提交
1240
					goto create_n_graft;
E
Eric Dumazet 已提交
1241
				if (n->nlmsg_flags & NLM_F_EXCL)
L
Linus Torvalds 已提交
1242
					return -EEXIST;
1243
				if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
L
Linus Torvalds 已提交
1244 1245 1246 1247 1248 1249 1250
					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
1251
				if (!q)
L
Linus Torvalds 已提交
1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272
					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
1273 1274 1275
				if ((n->nlmsg_flags & NLM_F_CREATE) &&
				    (n->nlmsg_flags & NLM_F_REPLACE) &&
				    ((n->nlmsg_flags & NLM_F_EXCL) ||
1276 1277
				     (tca[TCA_KIND] &&
				      nla_strcmp(tca[TCA_KIND], q->ops->id))))
L
Linus Torvalds 已提交
1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289
					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
1290
	if (n->nlmsg_flags & NLM_F_EXCL)
L
Linus Torvalds 已提交
1291
		return -EEXIST;
1292
	if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
L
Linus Torvalds 已提交
1293 1294 1295
		return -EINVAL;
	err = qdisc_change(q, tca);
	if (err == 0)
1296
		qdisc_notify(net, skb, n, clid, NULL, q);
L
Linus Torvalds 已提交
1297 1298 1299
	return err;

create_n_graft:
E
Eric Dumazet 已提交
1300
	if (!(n->nlmsg_flags & NLM_F_CREATE))
L
Linus Torvalds 已提交
1301
		return -ENOENT;
1302 1303 1304 1305 1306 1307 1308 1309
	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 {
1310
		struct netdev_queue *dev_queue;
1311 1312

		if (p && p->ops->cl_ops && p->ops->cl_ops->select_queue)
1313 1314 1315 1316 1317
			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);
1318

1319
		q = qdisc_create(dev, dev_queue, p,
1320
				 tcm->tcm_parent, tcm->tcm_handle,
1321
				 tca, &err);
1322
	}
L
Linus Torvalds 已提交
1323 1324 1325 1326 1327 1328 1329
	if (q == NULL) {
		if (err == -EAGAIN)
			goto replay;
		return err;
	}

graft:
1330 1331 1332 1333 1334
	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
1335
	}
1336

L
Linus Torvalds 已提交
1337 1338 1339 1340
	return 0;
}

static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid,
1341
			 u32 portid, u32 seq, u16 flags, int event)
L
Linus Torvalds 已提交
1342
{
1343
	struct gnet_stats_basic_cpu __percpu *cpu_bstats = NULL;
1344
	struct gnet_stats_queue __percpu *cpu_qstats = NULL;
L
Linus Torvalds 已提交
1345 1346
	struct tcmsg *tcm;
	struct nlmsghdr  *nlh;
1347
	unsigned char *b = skb_tail_pointer(skb);
L
Linus Torvalds 已提交
1348
	struct gnet_dump d;
1349
	struct qdisc_size_table *stab;
1350
	__u32 qlen;
L
Linus Torvalds 已提交
1351

1352
	cond_resched();
1353
	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1354 1355 1356
	if (!nlh)
		goto out_nlmsg_trim;
	tcm = nlmsg_data(nlh);
L
Linus Torvalds 已提交
1357
	tcm->tcm_family = AF_UNSPEC;
1358 1359
	tcm->tcm__pad1 = 0;
	tcm->tcm__pad2 = 0;
1360
	tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
L
Linus Torvalds 已提交
1361 1362 1363
	tcm->tcm_parent = clid;
	tcm->tcm_handle = q->handle;
	tcm->tcm_info = atomic_read(&q->refcnt);
1364 1365
	if (nla_put_string(skb, TCA_KIND, q->ops->id))
		goto nla_put_failure;
L
Linus Torvalds 已提交
1366
	if (q->ops->dump && q->ops->dump(q, skb) < 0)
1367
		goto nla_put_failure;
1368
	qlen = q->q.qlen;
L
Linus Torvalds 已提交
1369

1370 1371
	stab = rtnl_dereference(q->stab);
	if (stab && qdisc_dump_stab(skb, stab) < 0)
1372 1373
		goto nla_put_failure;

1374
	if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
1375
					 NULL, &d, TCA_PAD) < 0)
1376
		goto nla_put_failure;
L
Linus Torvalds 已提交
1377 1378

	if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0)
1379
		goto nla_put_failure;
L
Linus Torvalds 已提交
1380

1381
	if (qdisc_is_percpu_stats(q)) {
1382
		cpu_bstats = q->cpu_bstats;
1383 1384
		cpu_qstats = q->cpu_qstats;
	}
1385

1386 1387
	if (gnet_stats_copy_basic(qdisc_root_sleeping_running(q),
				  &d, cpu_bstats, &q->bstats) < 0 ||
1388
	    gnet_stats_copy_rate_est(&d, &q->rate_est) < 0 ||
1389
	    gnet_stats_copy_queue(&d, cpu_qstats, &q->qstats, qlen) < 0)
1390
		goto nla_put_failure;
1391

L
Linus Torvalds 已提交
1392
	if (gnet_stats_finish_copy(&d) < 0)
1393
		goto nla_put_failure;
1394

1395
	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
L
Linus Torvalds 已提交
1396 1397
	return skb->len;

1398
out_nlmsg_trim:
1399
nla_put_failure:
1400
	nlmsg_trim(skb, b);
L
Linus Torvalds 已提交
1401 1402 1403
	return -1;
}

1404 1405 1406 1407 1408
static bool tc_qdisc_dump_ignore(struct Qdisc *q)
{
	return (q->flags & TCQ_F_BUILTIN) ? true : false;
}

1409 1410 1411
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
1412 1413
{
	struct sk_buff *skb;
1414
	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
L
Linus Torvalds 已提交
1415 1416 1417 1418 1419

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

1420
	if (old && !tc_qdisc_dump_ignore(old)) {
1421
		if (tc_fill_qdisc(skb, old, clid, portid, n->nlmsg_seq,
E
Eric Dumazet 已提交
1422
				  0, RTM_DELQDISC) < 0)
L
Linus Torvalds 已提交
1423 1424
			goto err_out;
	}
1425
	if (new && !tc_qdisc_dump_ignore(new)) {
1426
		if (tc_fill_qdisc(skb, new, clid, portid, n->nlmsg_seq,
E
Eric Dumazet 已提交
1427
				  old ? NLM_F_REPLACE : 0, RTM_NEWQDISC) < 0)
L
Linus Torvalds 已提交
1428 1429 1430 1431
			goto err_out;
	}

	if (skb->len)
1432
		return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
E
Eric Dumazet 已提交
1433
				      n->nlmsg_flags & NLM_F_ECHO);
L
Linus Torvalds 已提交
1434 1435 1436 1437 1438 1439

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

1440 1441
static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb,
			      struct netlink_callback *cb,
1442
			      int *q_idx_p, int s_q_idx, bool recur)
1443 1444 1445
{
	int ret = 0, q_idx = *q_idx_p;
	struct Qdisc *q;
1446
	int b;
1447 1448 1449 1450 1451 1452 1453 1454 1455

	if (!root)
		return 0;

	q = root;
	if (q_idx < s_q_idx) {
		q_idx++;
	} else {
		if (!tc_qdisc_dump_ignore(q) &&
1456
		    tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
1457 1458
				  cb->nlh->nlmsg_seq, NLM_F_MULTI,
				  RTM_NEWQDISC) <= 0)
1459 1460 1461
			goto done;
		q_idx++;
	}
1462

1463 1464 1465 1466 1467 1468 1469
	/* 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)
1470 1471
		goto out;

1472
	hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) {
1473 1474 1475 1476
		if (q_idx < s_q_idx) {
			q_idx++;
			continue;
		}
E
Eric Dumazet 已提交
1477
		if (!tc_qdisc_dump_ignore(q) &&
1478
		    tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
1479 1480
				  cb->nlh->nlmsg_seq, NLM_F_MULTI,
				  RTM_NEWQDISC) <= 0)
1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492
			goto done;
		q_idx++;
	}

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

L
Linus Torvalds 已提交
1493 1494
static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb)
{
1495
	struct net *net = sock_net(skb->sk);
L
Linus Torvalds 已提交
1496 1497 1498 1499 1500 1501
	int idx, q_idx;
	int s_idx, s_q_idx;
	struct net_device *dev;

	s_idx = cb->args[0];
	s_q_idx = q_idx = cb->args[1];
1502

1503
	idx = 0;
1504 1505
	ASSERT_RTNL();
	for_each_netdev(net, dev) {
1506 1507
		struct netdev_queue *dev_queue;

L
Linus Torvalds 已提交
1508
		if (idx < s_idx)
1509
			goto cont;
L
Linus Torvalds 已提交
1510 1511 1512
		if (idx > s_idx)
			s_q_idx = 0;
		q_idx = 0;
1513

1514 1515
		if (tc_dump_qdisc_root(dev->qdisc, skb, cb, &q_idx, s_q_idx,
				       true) < 0)
1516 1517
			goto done;

1518 1519 1520
		dev_queue = dev_ingress_queue(dev);
		if (dev_queue &&
		    tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb,
1521
				       &q_idx, s_q_idx, false) < 0)
1522 1523
			goto done;

1524 1525
cont:
		idx++;
L
Linus Torvalds 已提交
1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542
	}

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

	return skb->len;
}



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



1543
static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n)
L
Linus Torvalds 已提交
1544
{
1545
	struct net *net = sock_net(skb->sk);
1546
	struct tcmsg *tcm = nlmsg_data(n);
1547
	struct nlattr *tca[TCA_MAX + 1];
L
Linus Torvalds 已提交
1548 1549
	struct net_device *dev;
	struct Qdisc *q = NULL;
1550
	const struct Qdisc_class_ops *cops;
L
Linus Torvalds 已提交
1551 1552
	unsigned long cl = 0;
	unsigned long new_cl;
1553 1554 1555
	u32 portid;
	u32 clid;
	u32 qid;
L
Linus Torvalds 已提交
1556 1557
	int err;

1558
	if ((n->nlmsg_type != RTM_GETTCLASS) &&
1559
	    !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1560 1561
		return -EPERM;

1562 1563 1564 1565
	err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
	if (err < 0)
		return err;

1566 1567 1568 1569
	dev = __dev_get_by_index(net, tcm->tcm_ifindex);
	if (!dev)
		return -ENODEV;

L
Linus Torvalds 已提交
1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584
	/*
	   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 */

1585 1586 1587 1588
	portid = tcm->tcm_parent;
	clid = tcm->tcm_handle;
	qid = TC_H_MAJ(clid);

1589 1590
	if (portid != TC_H_ROOT) {
		u32 qid1 = TC_H_MAJ(portid);
L
Linus Torvalds 已提交
1591 1592 1593 1594 1595 1596 1597 1598

		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)
1599
			qid = dev->qdisc->handle;
L
Linus Torvalds 已提交
1600 1601

		/* Now qid is genuine qdisc handle consistent
E
Eric Dumazet 已提交
1602 1603
		 * both with parent and child.
		 *
1604
		 * TC_H_MAJ(portid) still may be unspecified, complete it now.
L
Linus Torvalds 已提交
1605
		 */
1606 1607
		if (portid)
			portid = TC_H_MAKE(qid, portid);
L
Linus Torvalds 已提交
1608 1609
	} else {
		if (qid == 0)
1610
			qid = dev->qdisc->handle;
L
Linus Torvalds 已提交
1611 1612 1613
	}

	/* OK. Locate qdisc */
E
Eric Dumazet 已提交
1614 1615
	q = qdisc_lookup(dev, qid);
	if (!q)
L
Linus Torvalds 已提交
1616 1617 1618 1619 1620 1621 1622 1623 1624
		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) {
1625
		if (portid == TC_H_ROOT)
L
Linus Torvalds 已提交
1626 1627 1628 1629 1630 1631 1632 1633 1634
			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
1635 1636
		if (n->nlmsg_type != RTM_NEWTCLASS ||
		    !(n->nlmsg_flags & NLM_F_CREATE))
L
Linus Torvalds 已提交
1637 1638 1639
			goto out;
	} else {
		switch (n->nlmsg_type) {
1640
		case RTM_NEWTCLASS:
L
Linus Torvalds 已提交
1641
			err = -EEXIST;
E
Eric Dumazet 已提交
1642
			if (n->nlmsg_flags & NLM_F_EXCL)
L
Linus Torvalds 已提交
1643 1644 1645
				goto out;
			break;
		case RTM_DELTCLASS:
1646 1647 1648
			err = -EOPNOTSUPP;
			if (cops->delete)
				err = cops->delete(q, cl);
L
Linus Torvalds 已提交
1649
			if (err == 0)
1650 1651
				tclass_notify(net, skb, n, q, cl,
					      RTM_DELTCLASS);
L
Linus Torvalds 已提交
1652 1653
			goto out;
		case RTM_GETTCLASS:
1654
			err = tclass_notify(net, skb, n, q, cl, RTM_NEWTCLASS);
L
Linus Torvalds 已提交
1655 1656 1657 1658 1659 1660 1661 1662
			goto out;
		default:
			err = -EINVAL;
			goto out;
		}
	}

	new_cl = cl;
1663 1664
	err = -EOPNOTSUPP;
	if (cops->change)
1665
		err = cops->change(q, clid, portid, tca, &new_cl);
L
Linus Torvalds 已提交
1666
	if (err == 0)
1667
		tclass_notify(net, skb, n, q, new_cl, RTM_NEWTCLASS);
L
Linus Torvalds 已提交
1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678

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

	return err;
}


static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q,
			  unsigned long cl,
1679
			  u32 portid, u32 seq, u16 flags, int event)
L
Linus Torvalds 已提交
1680 1681 1682
{
	struct tcmsg *tcm;
	struct nlmsghdr  *nlh;
1683
	unsigned char *b = skb_tail_pointer(skb);
L
Linus Torvalds 已提交
1684
	struct gnet_dump d;
1685
	const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops;
L
Linus Torvalds 已提交
1686

1687
	cond_resched();
1688
	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1689 1690 1691
	if (!nlh)
		goto out_nlmsg_trim;
	tcm = nlmsg_data(nlh);
L
Linus Torvalds 已提交
1692
	tcm->tcm_family = AF_UNSPEC;
1693 1694
	tcm->tcm__pad1 = 0;
	tcm->tcm__pad2 = 0;
1695
	tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
L
Linus Torvalds 已提交
1696 1697 1698
	tcm->tcm_parent = q->handle;
	tcm->tcm_handle = q->handle;
	tcm->tcm_info = 0;
1699 1700
	if (nla_put_string(skb, TCA_KIND, q->ops->id))
		goto nla_put_failure;
L
Linus Torvalds 已提交
1701
	if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0)
1702
		goto nla_put_failure;
L
Linus Torvalds 已提交
1703

1704
	if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
1705
					 NULL, &d, TCA_PAD) < 0)
1706
		goto nla_put_failure;
L
Linus Torvalds 已提交
1707 1708

	if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0)
1709
		goto nla_put_failure;
L
Linus Torvalds 已提交
1710 1711

	if (gnet_stats_finish_copy(&d) < 0)
1712
		goto nla_put_failure;
L
Linus Torvalds 已提交
1713

1714
	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
L
Linus Torvalds 已提交
1715 1716
	return skb->len;

1717
out_nlmsg_trim:
1718
nla_put_failure:
1719
	nlmsg_trim(skb, b);
L
Linus Torvalds 已提交
1720 1721 1722
	return -1;
}

1723 1724 1725
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
1726 1727
{
	struct sk_buff *skb;
1728
	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
L
Linus Torvalds 已提交
1729 1730 1731 1732 1733

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

1734
	if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, event) < 0) {
L
Linus Torvalds 已提交
1735 1736 1737 1738
		kfree_skb(skb);
		return -EINVAL;
	}

1739
	return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
E
Eric Dumazet 已提交
1740
			      n->nlmsg_flags & NLM_F_ECHO);
L
Linus Torvalds 已提交
1741 1742
}

E
Eric Dumazet 已提交
1743 1744 1745 1746
struct qdisc_dump_args {
	struct qdisc_walker	w;
	struct sk_buff		*skb;
	struct netlink_callback	*cb;
L
Linus Torvalds 已提交
1747 1748
};

1749 1750
static int qdisc_class_dump(struct Qdisc *q, unsigned long cl,
			    struct qdisc_walker *arg)
L
Linus Torvalds 已提交
1751 1752 1753
{
	struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg;

1754
	return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).portid,
1755 1756
			      a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
			      RTM_NEWTCLASS);
L
Linus Torvalds 已提交
1757 1758
}

1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792
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;

	if (tc_qdisc_dump_ignore(q) ||
	    *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;
1793
	int b;
1794 1795 1796 1797 1798 1799 1800

	if (!root)
		return 0;

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

1801 1802 1803
	if (!qdisc_dev(root))
		return 0;

1804
	hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) {
1805 1806 1807 1808 1809 1810 1811
		if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0)
			return -1;
	}

	return 0;
}

L
Linus Torvalds 已提交
1812 1813
static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb)
{
1814
	struct tcmsg *tcm = nlmsg_data(cb->nlh);
1815
	struct net *net = sock_net(skb->sk);
1816
	struct netdev_queue *dev_queue;
L
Linus Torvalds 已提交
1817
	struct net_device *dev;
1818
	int t, s_t;
L
Linus Torvalds 已提交
1819

1820
	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
L
Linus Torvalds 已提交
1821
		return 0;
E
Eric Dumazet 已提交
1822 1823
	dev = dev_get_by_index(net, tcm->tcm_ifindex);
	if (!dev)
L
Linus Torvalds 已提交
1824 1825 1826 1827 1828
		return 0;

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

1829
	if (tc_dump_tclass_root(dev->qdisc, skb, tcm, cb, &t, s_t) < 0)
1830 1831
		goto done;

1832 1833 1834 1835
	dev_queue = dev_ingress_queue(dev);
	if (dev_queue &&
	    tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb,
				&t, s_t) < 0)
1836
		goto done;
L
Linus Torvalds 已提交
1837

1838
done:
L
Linus Torvalds 已提交
1839 1840 1841 1842 1843 1844 1845
	cb->args[0] = t;

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

/* Main classifier routine: scans classifier chain attached
E
Eric Dumazet 已提交
1846 1847
 * to this qdisc, (optionally) tests for protocol and asks
 * specific classifiers.
L
Linus Torvalds 已提交
1848
 */
1849 1850
int tc_classify(struct sk_buff *skb, const struct tcf_proto *tp,
		struct tcf_result *res, bool compat_mode)
1851
{
1852
	__be16 protocol = tc_skb_protocol(skb);
1853
#ifdef CONFIG_NET_CLS_ACT
1854
	const int max_reclassify_loop = 4;
1855 1856
	const struct tcf_proto *old_tp = tp;
	int limit = 0;
1857

1858 1859
reclassify:
#endif
J
John Fastabend 已提交
1860
	for (; tp; tp = rcu_dereference_bh(tp->next)) {
1861 1862
		int err;

E
Eric Dumazet 已提交
1863 1864 1865 1866
		if (tp->protocol != protocol &&
		    tp->protocol != htons(ETH_P_ALL))
			continue;

1867 1868
		err = tp->classify(skb, tp, res);
#ifdef CONFIG_NET_CLS_ACT
1869
		if (unlikely(err == TC_ACT_RECLASSIFY && !compat_mode))
1870 1871
			goto reset;
#endif
1872
		if (err >= 0)
1873 1874 1875
			return err;
	}

1876
	return TC_ACT_UNSPEC; /* signal: continue lookup */
L
Linus Torvalds 已提交
1877
#ifdef CONFIG_NET_CLS_ACT
1878
reset:
1879
	if (unlikely(limit++ >= max_reclassify_loop)) {
1880 1881 1882
		net_notice_ratelimited("%s: reclassify loop, rule prio %u, protocol %02x\n",
				       tp->q->ops->id, tp->prio & 0xffff,
				       ntohs(tp->protocol));
1883
		return TC_ACT_SHOT;
L
Linus Torvalds 已提交
1884
	}
1885 1886

	tp = old_tp;
1887
	protocol = tc_skb_protocol(skb);
1888
	goto reclassify;
1889
#endif
L
Linus Torvalds 已提交
1890
}
1891
EXPORT_SYMBOL(tc_classify);
L
Linus Torvalds 已提交
1892 1893 1894 1895 1896

#ifdef CONFIG_PROC_FS
static int psched_show(struct seq_file *seq, void *v)
{
	seq_printf(seq, "%08x %08x %08x %08x\n",
1897
		   (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1),
1898
		   1000000,
1899
		   (u32)NSEC_PER_SEC / hrtimer_resolution);
L
Linus Torvalds 已提交
1900 1901 1902 1903 1904 1905

	return 0;
}

static int psched_open(struct inode *inode, struct file *file)
{
1906
	return single_open(file, psched_show, NULL);
L
Linus Torvalds 已提交
1907 1908
}

1909
static const struct file_operations psched_fops = {
L
Linus Torvalds 已提交
1910 1911 1912 1913 1914
	.owner = THIS_MODULE,
	.open = psched_open,
	.read  = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
1915
};
1916 1917 1918 1919 1920

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

1921
	e = proc_create("psched", 0, net->proc_net, &psched_fops);
1922 1923 1924 1925 1926 1927 1928 1929
	if (e == NULL)
		return -ENOMEM;

	return 0;
}

static void __net_exit psched_net_exit(struct net *net)
{
1930
	remove_proc_entry("psched", net->proc_net);
1931 1932 1933 1934 1935 1936 1937 1938 1939 1940
}
#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
1941 1942
#endif

1943 1944 1945 1946 1947
static struct pernet_operations psched_net_ops = {
	.init = psched_net_init,
	.exit = psched_net_exit,
};

L
Linus Torvalds 已提交
1948 1949
static int __init pktsched_init(void)
{
1950 1951 1952 1953
	int err;

	err = register_pernet_subsys(&psched_net_ops);
	if (err) {
E
Eric Dumazet 已提交
1954
		pr_err("pktsched_init: "
1955 1956 1957 1958
		       "cannot initialize per netns operations\n");
		return err;
	}

1959
	register_qdisc(&pfifo_fast_ops);
L
Linus Torvalds 已提交
1960 1961
	register_qdisc(&pfifo_qdisc_ops);
	register_qdisc(&bfifo_qdisc_ops);
1962
	register_qdisc(&pfifo_head_drop_qdisc_ops);
1963
	register_qdisc(&mq_qdisc_ops);
1964
	register_qdisc(&noqueue_qdisc_ops);
L
Linus Torvalds 已提交
1965

1966 1967
	rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL, NULL);
	rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL, NULL);
1968 1969
	rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc,
		      NULL);
1970 1971
	rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL, NULL);
	rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL, NULL);
1972 1973
	rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass,
		      NULL);
1974

L
Linus Torvalds 已提交
1975 1976 1977 1978
	return 0;
}

subsys_initcall(pktsched_init);
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