sch_api.c 45.1 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 <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
   NET_XMIT_POLICED	- dropped by police.
     Expected action: backoff or error to real-time apps.

   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
   (root qdisc, all its children, children of children etc.)
 */

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

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

	list_for_each_entry(q, &root->list, list) {
		if (q->handle == handle)
			return q;
	}
	return NULL;
}

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void qdisc_list_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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		list_add_tail(&q->list, &root->list);
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	}
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}
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EXPORT_SYMBOL(qdisc_list_add);
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void qdisc_list_del(struct Qdisc *q)
{
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	if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS))
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		list_del(&q->list);
}
EXPORT_SYMBOL(qdisc_list_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 DEFINE_SPINLOCK(qdisc_stab_lock);

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);

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	spin_lock(&qdisc_stab_lock);
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	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++;
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		spin_unlock(&qdisc_stab_lock);
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		return stab;
	}

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	spin_unlock(&qdisc_stab_lock);
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	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));

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	spin_lock(&qdisc_stab_lock);
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	list_add_tail(&stab->list, &qdisc_stab_list);
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	spin_unlock(&qdisc_stab_lock);
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	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;

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

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	spin_unlock(&qdisc_stab_lock);
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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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	qdisc_unthrottled(wd->qdisc);
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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, bool throttle)
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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 (throttle)
		qdisc_throttled(wd->qdisc);
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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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	qdisc_unthrottled(wd->qdisc);
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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;
650
	struct hlist_node *next;
651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668
	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++) {
669
		hlist_for_each_entry_safe(cl, next, &ohash[i], hnode) {
670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722
			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);

723 724 725
/* Allocate an unique handle from space managed by kernel
 * Possible range is [8000-FFFF]:0000 (0x8000 values)
 */
L
Linus Torvalds 已提交
726 727
static u32 qdisc_alloc_handle(struct net_device *dev)
{
728
	int i = 0x8000;
L
Linus Torvalds 已提交
729 730 731 732 733 734
	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);
735 736 737 738
		if (!qdisc_lookup(dev, autohandle))
			return autohandle;
		cond_resched();
	} while	(--i > 0);
L
Linus Torvalds 已提交
739

740
	return 0;
L
Linus Torvalds 已提交
741 742
}

743 744
void qdisc_tree_decrease_qlen(struct Qdisc *sch, unsigned int n)
{
745
	const struct Qdisc_class_ops *cops;
746 747
	unsigned long cl;
	u32 parentid;
748
	int drops;
749 750 751

	if (n == 0)
		return;
752
	drops = max_t(int, n, 0);
753
	while ((parentid = sch->parent)) {
754 755 756
		if (TC_H_MAJ(parentid) == TC_H_MAJ(TC_H_INGRESS))
			return;

757
		sch = qdisc_lookup(qdisc_dev(sch), TC_H_MAJ(parentid));
758 759 760 761
		if (sch == NULL) {
			WARN_ON(parentid != TC_H_ROOT);
			return;
		}
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
		__qdisc_qstats_drop(sch, drops);
770 771 772
	}
}
EXPORT_SYMBOL(qdisc_tree_decrease_qlen);
L
Linus Torvalds 已提交
773

774 775
static void notify_and_destroy(struct net *net, struct sk_buff *skb,
			       struct nlmsghdr *n, u32 clid,
776 777 778
			       struct Qdisc *old, struct Qdisc *new)
{
	if (new || old)
779
		qdisc_notify(net, skb, n, clid, old, new);
L
Linus Torvalds 已提交
780

781
	if (old)
782 783 784 785 786 787 788 789 790 791
		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
792 793 794
 */

static int qdisc_graft(struct net_device *dev, struct Qdisc *parent,
795 796
		       struct sk_buff *skb, struct nlmsghdr *n, u32 classid,
		       struct Qdisc *new, struct Qdisc *old)
L
Linus Torvalds 已提交
797
{
798
	struct Qdisc *q = old;
799
	struct net *net = dev_net(dev);
L
Linus Torvalds 已提交
800 801
	int err = 0;

802
	if (parent == NULL) {
803 804 805 806
		unsigned int i, num_q, ingress;

		ingress = 0;
		num_q = dev->num_tx_queues;
807 808
		if ((q && q->flags & TCQ_F_INGRESS) ||
		    (new && new->flags & TCQ_F_INGRESS)) {
809 810
			num_q = 1;
			ingress = 1;
811 812
			if (!dev_ingress_queue(dev))
				return -ENOENT;
813 814 815 816 817
		}

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

818 819
		if (new && new->ops->attach)
			goto skip;
820

821
		for (i = 0; i < num_q; i++) {
822
			struct netdev_queue *dev_queue = dev_ingress_queue(dev);
823 824 825 826

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

827 828 829 830
			old = dev_graft_qdisc(dev_queue, new);
			if (new && i > 0)
				atomic_inc(&new->refcnt);

831 832
			if (!ingress)
				qdisc_destroy(old);
L
Linus Torvalds 已提交
833
		}
834

835
skip:
836
		if (!ingress) {
837 838
			notify_and_destroy(net, skb, n, classid,
					   dev->qdisc, new);
839 840 841
			if (new && !new->ops->attach)
				atomic_inc(&new->refcnt);
			dev->qdisc = new ? : &noop_qdisc;
842 843 844

			if (new && new->ops->attach)
				new->ops->attach(new);
845
		} else {
846
			notify_and_destroy(net, skb, n, classid, old, new);
847
		}
848

849 850
		if (dev->flags & IFF_UP)
			dev_activate(dev);
L
Linus Torvalds 已提交
851
	} else {
852
		const struct Qdisc_class_ops *cops = parent->ops->cl_ops;
L
Linus Torvalds 已提交
853

854 855
		err = -EOPNOTSUPP;
		if (cops && cops->graft) {
L
Linus Torvalds 已提交
856 857
			unsigned long cl = cops->get(parent, classid);
			if (cl) {
858
				err = cops->graft(parent, cl, new, &old);
L
Linus Torvalds 已提交
859
				cops->put(parent, cl);
860 861
			} else
				err = -ENOENT;
L
Linus Torvalds 已提交
862
		}
863
		if (!err)
864
			notify_and_destroy(net, skb, n, classid, old, new);
L
Linus Torvalds 已提交
865 866 867 868
	}
	return err;
}

869 870 871 872
/* 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
873 874 875 876 877 878 879
/*
   Allocate and initialize new qdisc.

   Parameters are passed via opt.
 */

static struct Qdisc *
880
qdisc_create(struct net_device *dev, struct netdev_queue *dev_queue,
881 882
	     struct Qdisc *p, u32 parent, u32 handle,
	     struct nlattr **tca, int *errp)
L
Linus Torvalds 已提交
883 884
{
	int err;
885
	struct nlattr *kind = tca[TCA_KIND];
L
Linus Torvalds 已提交
886 887
	struct Qdisc *sch;
	struct Qdisc_ops *ops;
888
	struct qdisc_size_table *stab;
L
Linus Torvalds 已提交
889 890

	ops = qdisc_lookup_ops(kind);
891
#ifdef CONFIG_MODULES
L
Linus Torvalds 已提交
892 893
	if (ops == NULL && kind != NULL) {
		char name[IFNAMSIZ];
894
		if (nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) {
L
Linus Torvalds 已提交
895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918
			/* 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

919
	err = -ENOENT;
L
Linus Torvalds 已提交
920 921 922
	if (ops == NULL)
		goto err_out;

923
	sch = qdisc_alloc(dev_queue, ops);
924 925
	if (IS_ERR(sch)) {
		err = PTR_ERR(sch);
L
Linus Torvalds 已提交
926
		goto err_out2;
927
	}
L
Linus Torvalds 已提交
928

929 930
	sch->parent = parent;

931
	if (handle == TC_H_INGRESS) {
L
Linus Torvalds 已提交
932
		sch->flags |= TCQ_F_INGRESS;
933
		handle = TC_H_MAKE(TC_H_INGRESS, 0);
934
		lockdep_set_class(qdisc_lock(sch), &qdisc_rx_lock);
935 936 937 938 939 940 941
	} else {
		if (handle == 0) {
			handle = qdisc_alloc_handle(dev);
			err = -ENOMEM;
			if (handle == 0)
				goto err_out3;
		}
942
		lockdep_set_class(qdisc_lock(sch), &qdisc_tx_lock);
943 944
		if (!netif_is_multiqueue(dev))
			sch->flags |= TCQ_F_ONETXQUEUE;
L
Linus Torvalds 已提交
945 946
	}

947
	sch->handle = handle;
L
Linus Torvalds 已提交
948

949
	if (!ops->init || (err = ops->init(sch, tca[TCA_OPTIONS])) == 0) {
950 951
		if (qdisc_is_percpu_stats(sch)) {
			sch->cpu_bstats =
952
				netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu);
953 954
			if (!sch->cpu_bstats)
				goto err_out4;
955 956 957 958

			sch->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
			if (!sch->cpu_qstats)
				goto err_out4;
959 960
		}

961 962 963 964
		if (tca[TCA_STAB]) {
			stab = qdisc_get_stab(tca[TCA_STAB]);
			if (IS_ERR(stab)) {
				err = PTR_ERR(stab);
965
				goto err_out4;
966
			}
E
Eric Dumazet 已提交
967
			rcu_assign_pointer(sch->stab, stab);
968
		}
969
		if (tca[TCA_RATE]) {
970 971
			spinlock_t *root_lock;

972 973 974 975
			err = -EOPNOTSUPP;
			if (sch->flags & TCQ_F_MQROOT)
				goto err_out4;

976
			if ((sch->parent != TC_H_ROOT) &&
977 978
			    !(sch->flags & TCQ_F_INGRESS) &&
			    (!p || !(p->flags & TCQ_F_MQROOT)))
979 980 981 982
				root_lock = qdisc_root_sleeping_lock(sch);
			else
				root_lock = qdisc_lock(sch);

983 984 985 986 987
			err = gen_new_estimator(&sch->bstats,
						sch->cpu_bstats,
						&sch->rate_est,
						root_lock,
						tca[TCA_RATE]);
988 989
			if (err)
				goto err_out4;
990
		}
991 992

		qdisc_list_add(sch);
L
Linus Torvalds 已提交
993 994 995 996 997

		return sch;
	}
err_out3:
	dev_put(dev);
998
	kfree((char *) sch - sch->padded);
L
Linus Torvalds 已提交
999 1000 1001 1002 1003
err_out2:
	module_put(ops->owner);
err_out:
	*errp = err;
	return NULL;
1004 1005

err_out4:
1006
	free_percpu(sch->cpu_bstats);
1007
	free_percpu(sch->cpu_qstats);
1008 1009 1010 1011
	/*
	 * Any broken qdiscs that would require a ops->reset() here?
	 * The qdisc was never in action so it shouldn't be necessary.
	 */
E
Eric Dumazet 已提交
1012
	qdisc_put_stab(rtnl_dereference(sch->stab));
1013 1014 1015
	if (ops->destroy)
		ops->destroy(sch);
	goto err_out3;
L
Linus Torvalds 已提交
1016 1017
}

1018
static int qdisc_change(struct Qdisc *sch, struct nlattr **tca)
L
Linus Torvalds 已提交
1019
{
E
Eric Dumazet 已提交
1020
	struct qdisc_size_table *ostab, *stab = NULL;
1021
	int err = 0;
L
Linus Torvalds 已提交
1022

1023
	if (tca[TCA_OPTIONS]) {
L
Linus Torvalds 已提交
1024 1025
		if (sch->ops->change == NULL)
			return -EINVAL;
1026
		err = sch->ops->change(sch, tca[TCA_OPTIONS]);
L
Linus Torvalds 已提交
1027 1028 1029
		if (err)
			return err;
	}
1030 1031 1032 1033 1034 1035 1036

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

E
Eric Dumazet 已提交
1037 1038 1039
	ostab = rtnl_dereference(sch->stab);
	rcu_assign_pointer(sch->stab, stab);
	qdisc_put_stab(ostab);
1040

1041
	if (tca[TCA_RATE]) {
1042 1043
		/* NB: ignores errors from replace_estimator
		   because change can't be undone. */
1044 1045
		if (sch->flags & TCQ_F_MQROOT)
			goto out;
1046 1047 1048 1049 1050
		gen_replace_estimator(&sch->bstats,
				      sch->cpu_bstats,
				      &sch->rate_est,
				      qdisc_root_sleeping_lock(sch),
				      tca[TCA_RATE]);
1051 1052
	}
out:
L
Linus Torvalds 已提交
1053 1054 1055
	return 0;
}

E
Eric Dumazet 已提交
1056 1057
struct check_loop_arg {
	struct qdisc_walker	w;
L
Linus Torvalds 已提交
1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082
	struct Qdisc		*p;
	int			depth;
};

static int check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w);

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;
1083
	const struct Qdisc_class_ops *cops = q->ops->cl_ops;
L
Linus Torvalds 已提交
1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098
	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.
 */

1099
static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n)
L
Linus Torvalds 已提交
1100
{
1101
	struct net *net = sock_net(skb->sk);
1102
	struct tcmsg *tcm = nlmsg_data(n);
1103
	struct nlattr *tca[TCA_MAX + 1];
L
Linus Torvalds 已提交
1104
	struct net_device *dev;
1105
	u32 clid;
L
Linus Torvalds 已提交
1106 1107 1108 1109
	struct Qdisc *q = NULL;
	struct Qdisc *p = NULL;
	int err;

1110
	if ((n->nlmsg_type != RTM_GETQDISC) &&
1111
	    !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1112 1113
		return -EPERM;

1114 1115 1116 1117
	err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
	if (err < 0)
		return err;

1118 1119 1120 1121 1122
	dev = __dev_get_by_index(net, tcm->tcm_ifindex);
	if (!dev)
		return -ENODEV;

	clid = tcm->tcm_parent;
L
Linus Torvalds 已提交
1123 1124 1125
	if (clid) {
		if (clid != TC_H_ROOT) {
			if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) {
E
Eric Dumazet 已提交
1126 1127
				p = qdisc_lookup(dev, TC_H_MAJ(clid));
				if (!p)
L
Linus Torvalds 已提交
1128 1129
					return -ENOENT;
				q = qdisc_leaf(p, clid);
E
Eric Dumazet 已提交
1130 1131
			} else if (dev_ingress_queue(dev)) {
				q = dev_ingress_queue(dev)->qdisc_sleeping;
1132
			}
L
Linus Torvalds 已提交
1133
		} else {
1134
			q = dev->qdisc;
L
Linus Torvalds 已提交
1135 1136 1137 1138 1139 1140 1141
		}
		if (!q)
			return -ENOENT;

		if (tcm->tcm_handle && q->handle != tcm->tcm_handle)
			return -EINVAL;
	} else {
E
Eric Dumazet 已提交
1142 1143
		q = qdisc_lookup(dev, tcm->tcm_handle);
		if (!q)
L
Linus Torvalds 已提交
1144 1145 1146
			return -ENOENT;
	}

1147
	if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
L
Linus Torvalds 已提交
1148 1149 1150 1151 1152 1153 1154
		return -EINVAL;

	if (n->nlmsg_type == RTM_DELQDISC) {
		if (!clid)
			return -EINVAL;
		if (q->handle == 0)
			return -ENOENT;
E
Eric Dumazet 已提交
1155 1156
		err = qdisc_graft(dev, p, skb, n, clid, NULL, q);
		if (err != 0)
L
Linus Torvalds 已提交
1157 1158
			return err;
	} else {
1159
		qdisc_notify(net, skb, n, clid, NULL, q);
L
Linus Torvalds 已提交
1160 1161 1162 1163 1164
	}
	return 0;
}

/*
E
Eric Dumazet 已提交
1165
 * Create/change qdisc.
L
Linus Torvalds 已提交
1166 1167
 */

1168
static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n)
L
Linus Torvalds 已提交
1169
{
1170
	struct net *net = sock_net(skb->sk);
L
Linus Torvalds 已提交
1171
	struct tcmsg *tcm;
1172
	struct nlattr *tca[TCA_MAX + 1];
L
Linus Torvalds 已提交
1173 1174 1175 1176 1177
	struct net_device *dev;
	u32 clid;
	struct Qdisc *q, *p;
	int err;

1178
	if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1179 1180
		return -EPERM;

L
Linus Torvalds 已提交
1181 1182
replay:
	/* Reinit, just in case something touches this. */
1183 1184 1185 1186
	err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
	if (err < 0)
		return err;

1187
	tcm = nlmsg_data(n);
L
Linus Torvalds 已提交
1188 1189 1190
	clid = tcm->tcm_parent;
	q = p = NULL;

E
Eric Dumazet 已提交
1191 1192
	dev = __dev_get_by_index(net, tcm->tcm_ifindex);
	if (!dev)
L
Linus Torvalds 已提交
1193 1194
		return -ENODEV;

1195

L
Linus Torvalds 已提交
1196 1197 1198
	if (clid) {
		if (clid != TC_H_ROOT) {
			if (clid != TC_H_INGRESS) {
E
Eric Dumazet 已提交
1199 1200
				p = qdisc_lookup(dev, TC_H_MAJ(clid));
				if (!p)
L
Linus Torvalds 已提交
1201 1202
					return -ENOENT;
				q = qdisc_leaf(p, clid);
E
Eric Dumazet 已提交
1203 1204
			} else if (dev_ingress_queue_create(dev)) {
				q = dev_ingress_queue(dev)->qdisc_sleeping;
L
Linus Torvalds 已提交
1205 1206
			}
		} else {
1207
			q = dev->qdisc;
L
Linus Torvalds 已提交
1208 1209 1210 1211 1212 1213 1214 1215
		}

		/* 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
1216
				if (q && !(n->nlmsg_flags & NLM_F_REPLACE))
L
Linus Torvalds 已提交
1217 1218 1219
					return -EEXIST;
				if (TC_H_MIN(tcm->tcm_handle))
					return -EINVAL;
E
Eric Dumazet 已提交
1220 1221
				q = qdisc_lookup(dev, tcm->tcm_handle);
				if (!q)
L
Linus Torvalds 已提交
1222
					goto create_n_graft;
E
Eric Dumazet 已提交
1223
				if (n->nlmsg_flags & NLM_F_EXCL)
L
Linus Torvalds 已提交
1224
					return -EEXIST;
1225
				if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
L
Linus Torvalds 已提交
1226 1227 1228 1229 1230 1231 1232
					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
1233
				if (!q)
L
Linus Torvalds 已提交
1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254
					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
1255 1256 1257
				if ((n->nlmsg_flags & NLM_F_CREATE) &&
				    (n->nlmsg_flags & NLM_F_REPLACE) &&
				    ((n->nlmsg_flags & NLM_F_EXCL) ||
1258 1259
				     (tca[TCA_KIND] &&
				      nla_strcmp(tca[TCA_KIND], q->ops->id))))
L
Linus Torvalds 已提交
1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271
					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
1272
	if (n->nlmsg_flags & NLM_F_EXCL)
L
Linus Torvalds 已提交
1273
		return -EEXIST;
1274
	if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
L
Linus Torvalds 已提交
1275 1276 1277
		return -EINVAL;
	err = qdisc_change(q, tca);
	if (err == 0)
1278
		qdisc_notify(net, skb, n, clid, NULL, q);
L
Linus Torvalds 已提交
1279 1280 1281
	return err;

create_n_graft:
E
Eric Dumazet 已提交
1282
	if (!(n->nlmsg_flags & NLM_F_CREATE))
L
Linus Torvalds 已提交
1283
		return -ENOENT;
1284 1285 1286 1287 1288 1289 1290 1291
	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 {
1292
		struct netdev_queue *dev_queue;
1293 1294

		if (p && p->ops->cl_ops && p->ops->cl_ops->select_queue)
1295 1296 1297 1298 1299
			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);
1300

1301
		q = qdisc_create(dev, dev_queue, p,
1302
				 tcm->tcm_parent, tcm->tcm_handle,
1303
				 tca, &err);
1304
	}
L
Linus Torvalds 已提交
1305 1306 1307 1308 1309 1310 1311
	if (q == NULL) {
		if (err == -EAGAIN)
			goto replay;
		return err;
	}

graft:
1312 1313 1314 1315 1316
	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
1317
	}
1318

L
Linus Torvalds 已提交
1319 1320 1321 1322
	return 0;
}

static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid,
1323
			 u32 portid, u32 seq, u16 flags, int event)
L
Linus Torvalds 已提交
1324
{
1325
	struct gnet_stats_basic_cpu __percpu *cpu_bstats = NULL;
1326
	struct gnet_stats_queue __percpu *cpu_qstats = NULL;
L
Linus Torvalds 已提交
1327 1328
	struct tcmsg *tcm;
	struct nlmsghdr  *nlh;
1329
	unsigned char *b = skb_tail_pointer(skb);
L
Linus Torvalds 已提交
1330
	struct gnet_dump d;
E
Eric Dumazet 已提交
1331
	struct qdisc_size_table *stab;
1332
	__u32 qlen;
L
Linus Torvalds 已提交
1333

1334
	cond_resched();
1335
	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1336 1337 1338
	if (!nlh)
		goto out_nlmsg_trim;
	tcm = nlmsg_data(nlh);
L
Linus Torvalds 已提交
1339
	tcm->tcm_family = AF_UNSPEC;
1340 1341
	tcm->tcm__pad1 = 0;
	tcm->tcm__pad2 = 0;
1342
	tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
L
Linus Torvalds 已提交
1343 1344 1345
	tcm->tcm_parent = clid;
	tcm->tcm_handle = q->handle;
	tcm->tcm_info = atomic_read(&q->refcnt);
1346 1347
	if (nla_put_string(skb, TCA_KIND, q->ops->id))
		goto nla_put_failure;
L
Linus Torvalds 已提交
1348
	if (q->ops->dump && q->ops->dump(q, skb) < 0)
1349
		goto nla_put_failure;
1350
	qlen = q->q.qlen;
L
Linus Torvalds 已提交
1351

E
Eric Dumazet 已提交
1352 1353
	stab = rtnl_dereference(q->stab);
	if (stab && qdisc_dump_stab(skb, stab) < 0)
1354 1355
		goto nla_put_failure;

1356 1357
	if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
					 qdisc_root_sleeping_lock(q), &d) < 0)
1358
		goto nla_put_failure;
L
Linus Torvalds 已提交
1359 1360

	if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0)
1361
		goto nla_put_failure;
L
Linus Torvalds 已提交
1362

1363
	if (qdisc_is_percpu_stats(q)) {
1364
		cpu_bstats = q->cpu_bstats;
1365 1366
		cpu_qstats = q->cpu_qstats;
	}
1367 1368

	if (gnet_stats_copy_basic(&d, cpu_bstats, &q->bstats) < 0 ||
1369
	    gnet_stats_copy_rate_est(&d, &q->bstats, &q->rate_est) < 0 ||
1370
	    gnet_stats_copy_queue(&d, cpu_qstats, &q->qstats, qlen) < 0)
1371
		goto nla_put_failure;
1372

L
Linus Torvalds 已提交
1373
	if (gnet_stats_finish_copy(&d) < 0)
1374
		goto nla_put_failure;
1375

1376
	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
L
Linus Torvalds 已提交
1377 1378
	return skb->len;

1379
out_nlmsg_trim:
1380
nla_put_failure:
1381
	nlmsg_trim(skb, b);
L
Linus Torvalds 已提交
1382 1383 1384
	return -1;
}

E
Eric Dumazet 已提交
1385 1386 1387 1388 1389
static bool tc_qdisc_dump_ignore(struct Qdisc *q)
{
	return (q->flags & TCQ_F_BUILTIN) ? true : false;
}

1390 1391 1392
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
1393 1394
{
	struct sk_buff *skb;
1395
	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
L
Linus Torvalds 已提交
1396 1397 1398 1399 1400

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

E
Eric Dumazet 已提交
1401
	if (old && !tc_qdisc_dump_ignore(old)) {
1402
		if (tc_fill_qdisc(skb, old, clid, portid, n->nlmsg_seq,
E
Eric Dumazet 已提交
1403
				  0, RTM_DELQDISC) < 0)
L
Linus Torvalds 已提交
1404 1405
			goto err_out;
	}
E
Eric Dumazet 已提交
1406
	if (new && !tc_qdisc_dump_ignore(new)) {
1407
		if (tc_fill_qdisc(skb, new, clid, portid, n->nlmsg_seq,
E
Eric Dumazet 已提交
1408
				  old ? NLM_F_REPLACE : 0, RTM_NEWQDISC) < 0)
L
Linus Torvalds 已提交
1409 1410 1411 1412
			goto err_out;
	}

	if (skb->len)
1413
		return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
E
Eric Dumazet 已提交
1414
				      n->nlmsg_flags & NLM_F_ECHO);
L
Linus Torvalds 已提交
1415 1416 1417 1418 1419 1420

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

1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435
static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb,
			      struct netlink_callback *cb,
			      int *q_idx_p, int s_q_idx)
{
	int ret = 0, q_idx = *q_idx_p;
	struct Qdisc *q;

	if (!root)
		return 0;

	q = root;
	if (q_idx < s_q_idx) {
		q_idx++;
	} else {
		if (!tc_qdisc_dump_ignore(q) &&
1436
		    tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
1437 1438 1439 1440 1441 1442 1443 1444 1445
				  cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0)
			goto done;
		q_idx++;
	}
	list_for_each_entry(q, &root->list, list) {
		if (q_idx < s_q_idx) {
			q_idx++;
			continue;
		}
E
Eric Dumazet 已提交
1446
		if (!tc_qdisc_dump_ignore(q) &&
1447
		    tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460
				  cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0)
			goto done;
		q_idx++;
	}

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

L
Linus Torvalds 已提交
1461 1462
static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb)
{
1463
	struct net *net = sock_net(skb->sk);
L
Linus Torvalds 已提交
1464 1465 1466 1467 1468 1469
	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];
1470

1471
	idx = 0;
1472 1473
	ASSERT_RTNL();
	for_each_netdev(net, dev) {
1474 1475
		struct netdev_queue *dev_queue;

L
Linus Torvalds 已提交
1476
		if (idx < s_idx)
1477
			goto cont;
L
Linus Torvalds 已提交
1478 1479 1480
		if (idx > s_idx)
			s_q_idx = 0;
		q_idx = 0;
1481

1482
		if (tc_dump_qdisc_root(dev->qdisc, skb, cb, &q_idx, s_q_idx) < 0)
1483 1484
			goto done;

1485 1486 1487 1488
		dev_queue = dev_ingress_queue(dev);
		if (dev_queue &&
		    tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb,
				       &q_idx, s_q_idx) < 0)
1489 1490
			goto done;

1491 1492
cont:
		idx++;
L
Linus Torvalds 已提交
1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509
	}

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

	return skb->len;
}



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



1510
static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n)
L
Linus Torvalds 已提交
1511
{
1512
	struct net *net = sock_net(skb->sk);
1513
	struct tcmsg *tcm = nlmsg_data(n);
1514
	struct nlattr *tca[TCA_MAX + 1];
L
Linus Torvalds 已提交
1515 1516
	struct net_device *dev;
	struct Qdisc *q = NULL;
1517
	const struct Qdisc_class_ops *cops;
L
Linus Torvalds 已提交
1518 1519
	unsigned long cl = 0;
	unsigned long new_cl;
1520 1521 1522
	u32 portid;
	u32 clid;
	u32 qid;
L
Linus Torvalds 已提交
1523 1524
	int err;

1525
	if ((n->nlmsg_type != RTM_GETTCLASS) &&
1526
	    !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1527 1528
		return -EPERM;

1529 1530 1531 1532
	err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
	if (err < 0)
		return err;

1533 1534 1535 1536
	dev = __dev_get_by_index(net, tcm->tcm_ifindex);
	if (!dev)
		return -ENODEV;

L
Linus Torvalds 已提交
1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551
	/*
	   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 */

1552 1553 1554 1555
	portid = tcm->tcm_parent;
	clid = tcm->tcm_handle;
	qid = TC_H_MAJ(clid);

1556 1557
	if (portid != TC_H_ROOT) {
		u32 qid1 = TC_H_MAJ(portid);
L
Linus Torvalds 已提交
1558 1559 1560 1561 1562 1563 1564 1565

		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)
1566
			qid = dev->qdisc->handle;
L
Linus Torvalds 已提交
1567 1568

		/* Now qid is genuine qdisc handle consistent
E
Eric Dumazet 已提交
1569 1570
		 * both with parent and child.
		 *
1571
		 * TC_H_MAJ(portid) still may be unspecified, complete it now.
L
Linus Torvalds 已提交
1572
		 */
1573 1574
		if (portid)
			portid = TC_H_MAKE(qid, portid);
L
Linus Torvalds 已提交
1575 1576
	} else {
		if (qid == 0)
1577
			qid = dev->qdisc->handle;
L
Linus Torvalds 已提交
1578 1579 1580
	}

	/* OK. Locate qdisc */
E
Eric Dumazet 已提交
1581 1582
	q = qdisc_lookup(dev, qid);
	if (!q)
L
Linus Torvalds 已提交
1583 1584 1585 1586 1587 1588 1589 1590 1591
		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) {
1592
		if (portid == TC_H_ROOT)
L
Linus Torvalds 已提交
1593 1594 1595 1596 1597 1598 1599 1600 1601
			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
1602 1603
		if (n->nlmsg_type != RTM_NEWTCLASS ||
		    !(n->nlmsg_flags & NLM_F_CREATE))
L
Linus Torvalds 已提交
1604 1605 1606
			goto out;
	} else {
		switch (n->nlmsg_type) {
1607
		case RTM_NEWTCLASS:
L
Linus Torvalds 已提交
1608
			err = -EEXIST;
E
Eric Dumazet 已提交
1609
			if (n->nlmsg_flags & NLM_F_EXCL)
L
Linus Torvalds 已提交
1610 1611 1612
				goto out;
			break;
		case RTM_DELTCLASS:
1613 1614 1615
			err = -EOPNOTSUPP;
			if (cops->delete)
				err = cops->delete(q, cl);
L
Linus Torvalds 已提交
1616
			if (err == 0)
1617
				tclass_notify(net, skb, n, q, cl, RTM_DELTCLASS);
L
Linus Torvalds 已提交
1618 1619
			goto out;
		case RTM_GETTCLASS:
1620
			err = tclass_notify(net, skb, n, q, cl, RTM_NEWTCLASS);
L
Linus Torvalds 已提交
1621 1622 1623 1624 1625 1626 1627 1628
			goto out;
		default:
			err = -EINVAL;
			goto out;
		}
	}

	new_cl = cl;
1629 1630
	err = -EOPNOTSUPP;
	if (cops->change)
1631
		err = cops->change(q, clid, portid, tca, &new_cl);
L
Linus Torvalds 已提交
1632
	if (err == 0)
1633
		tclass_notify(net, skb, n, q, new_cl, RTM_NEWTCLASS);
L
Linus Torvalds 已提交
1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644

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

	return err;
}


static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q,
			  unsigned long cl,
1645
			  u32 portid, u32 seq, u16 flags, int event)
L
Linus Torvalds 已提交
1646 1647 1648
{
	struct tcmsg *tcm;
	struct nlmsghdr  *nlh;
1649
	unsigned char *b = skb_tail_pointer(skb);
L
Linus Torvalds 已提交
1650
	struct gnet_dump d;
1651
	const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops;
L
Linus Torvalds 已提交
1652

1653
	cond_resched();
1654
	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1655 1656 1657
	if (!nlh)
		goto out_nlmsg_trim;
	tcm = nlmsg_data(nlh);
L
Linus Torvalds 已提交
1658
	tcm->tcm_family = AF_UNSPEC;
1659 1660
	tcm->tcm__pad1 = 0;
	tcm->tcm__pad2 = 0;
1661
	tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
L
Linus Torvalds 已提交
1662 1663 1664
	tcm->tcm_parent = q->handle;
	tcm->tcm_handle = q->handle;
	tcm->tcm_info = 0;
1665 1666
	if (nla_put_string(skb, TCA_KIND, q->ops->id))
		goto nla_put_failure;
L
Linus Torvalds 已提交
1667
	if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0)
1668
		goto nla_put_failure;
L
Linus Torvalds 已提交
1669

1670 1671
	if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
					 qdisc_root_sleeping_lock(q), &d) < 0)
1672
		goto nla_put_failure;
L
Linus Torvalds 已提交
1673 1674

	if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0)
1675
		goto nla_put_failure;
L
Linus Torvalds 已提交
1676 1677

	if (gnet_stats_finish_copy(&d) < 0)
1678
		goto nla_put_failure;
L
Linus Torvalds 已提交
1679

1680
	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
L
Linus Torvalds 已提交
1681 1682
	return skb->len;

1683
out_nlmsg_trim:
1684
nla_put_failure:
1685
	nlmsg_trim(skb, b);
L
Linus Torvalds 已提交
1686 1687 1688
	return -1;
}

1689 1690 1691
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
1692 1693
{
	struct sk_buff *skb;
1694
	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
L
Linus Torvalds 已提交
1695 1696 1697 1698 1699

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

1700
	if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, event) < 0) {
L
Linus Torvalds 已提交
1701 1702 1703 1704
		kfree_skb(skb);
		return -EINVAL;
	}

1705
	return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
E
Eric Dumazet 已提交
1706
			      n->nlmsg_flags & NLM_F_ECHO);
L
Linus Torvalds 已提交
1707 1708
}

E
Eric Dumazet 已提交
1709 1710 1711 1712
struct qdisc_dump_args {
	struct qdisc_walker	w;
	struct sk_buff		*skb;
	struct netlink_callback	*cb;
L
Linus Torvalds 已提交
1713 1714 1715 1716 1717 1718
};

static int qdisc_class_dump(struct Qdisc *q, unsigned long cl, struct qdisc_walker *arg)
{
	struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg;

1719
	return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).portid,
L
Linus Torvalds 已提交
1720 1721 1722
			      a->cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTCLASS);
}

1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771
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;

	if (!root)
		return 0;

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

	list_for_each_entry(q, &root->list, list) {
		if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0)
			return -1;
	}

	return 0;
}

L
Linus Torvalds 已提交
1772 1773
static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb)
{
1774
	struct tcmsg *tcm = nlmsg_data(cb->nlh);
1775
	struct net *net = sock_net(skb->sk);
1776
	struct netdev_queue *dev_queue;
L
Linus Torvalds 已提交
1777
	struct net_device *dev;
1778
	int t, s_t;
L
Linus Torvalds 已提交
1779

1780
	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
L
Linus Torvalds 已提交
1781
		return 0;
E
Eric Dumazet 已提交
1782 1783
	dev = dev_get_by_index(net, tcm->tcm_ifindex);
	if (!dev)
L
Linus Torvalds 已提交
1784 1785 1786 1787 1788
		return 0;

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

1789
	if (tc_dump_tclass_root(dev->qdisc, skb, tcm, cb, &t, s_t) < 0)
1790 1791
		goto done;

1792 1793 1794 1795
	dev_queue = dev_ingress_queue(dev);
	if (dev_queue &&
	    tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb,
				&t, s_t) < 0)
1796
		goto done;
L
Linus Torvalds 已提交
1797

1798
done:
L
Linus Torvalds 已提交
1799 1800 1801 1802 1803 1804 1805
	cb->args[0] = t;

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

/* Main classifier routine: scans classifier chain attached
E
Eric Dumazet 已提交
1806 1807
 * to this qdisc, (optionally) tests for protocol and asks
 * specific classifiers.
L
Linus Torvalds 已提交
1808
 */
1809
int tc_classify_compat(struct sk_buff *skb, const struct tcf_proto *tp,
1810 1811
		       struct tcf_result *res)
{
1812
	__be16 protocol = tc_skb_protocol(skb);
E
Eric Dumazet 已提交
1813
	int err;
1814

J
John Fastabend 已提交
1815
	for (; tp; tp = rcu_dereference_bh(tp->next)) {
E
Eric Dumazet 已提交
1816 1817 1818 1819 1820
		if (tp->protocol != protocol &&
		    tp->protocol != htons(ETH_P_ALL))
			continue;
		err = tp->classify(skb, tp, res);

1821
		if (err >= 0)
1822 1823 1824 1825 1826 1827
			return err;
	}
	return -1;
}
EXPORT_SYMBOL(tc_classify_compat);

1828
int tc_classify(struct sk_buff *skb, const struct tcf_proto *tp,
1829
		struct tcf_result *res)
L
Linus Torvalds 已提交
1830 1831 1832
{
	int err = 0;
#ifdef CONFIG_NET_CLS_ACT
1833
	const struct tcf_proto *otp = tp;
1834
	int limit = 0;
L
Linus Torvalds 已提交
1835
reclassify:
1836
#endif
L
Linus Torvalds 已提交
1837

1838
	err = tc_classify_compat(skb, tp, res);
L
Linus Torvalds 已提交
1839
#ifdef CONFIG_NET_CLS_ACT
1840 1841 1842
	if (err == TC_ACT_RECLASSIFY) {
		tp = otp;

1843
		if (unlikely(limit++ >= MAX_REC_LOOP)) {
1844 1845 1846 1847
			net_notice_ratelimited("%s: packet reclassify loop rule prio %u protocol %02x\n",
					       tp->q->ops->id,
					       tp->prio & 0xffff,
					       ntohs(tp->protocol));
1848
			return TC_ACT_SHOT;
L
Linus Torvalds 已提交
1849
		}
1850
		goto reclassify;
L
Linus Torvalds 已提交
1851
	}
1852 1853
#endif
	return err;
L
Linus Torvalds 已提交
1854
}
1855
EXPORT_SYMBOL(tc_classify);
L
Linus Torvalds 已提交
1856

1857
bool tcf_destroy(struct tcf_proto *tp, bool force)
1858
{
1859 1860 1861 1862 1863 1864 1865
	if (tp->ops->destroy(tp, force)) {
		module_put(tp->ops->owner);
		kfree_rcu(tp, rcu);
		return true;
	}

	return false;
1866 1867
}

J
John Fastabend 已提交
1868
void tcf_destroy_chain(struct tcf_proto __rcu **fl)
1869 1870 1871
{
	struct tcf_proto *tp;

J
John Fastabend 已提交
1872 1873
	while ((tp = rtnl_dereference(*fl)) != NULL) {
		RCU_INIT_POINTER(*fl, tp->next);
1874
		tcf_destroy(tp, true);
1875 1876 1877 1878
	}
}
EXPORT_SYMBOL(tcf_destroy_chain);

L
Linus Torvalds 已提交
1879 1880 1881 1882
#ifdef CONFIG_PROC_FS
static int psched_show(struct seq_file *seq, void *v)
{
	seq_printf(seq, "%08x %08x %08x %08x\n",
1883
		   (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1),
P
Patrick McHardy 已提交
1884
		   1000000,
1885
		   (u32)NSEC_PER_SEC / hrtimer_resolution);
L
Linus Torvalds 已提交
1886 1887 1888 1889 1890 1891

	return 0;
}

static int psched_open(struct inode *inode, struct file *file)
{
1892
	return single_open(file, psched_show, NULL);
L
Linus Torvalds 已提交
1893 1894
}

1895
static const struct file_operations psched_fops = {
L
Linus Torvalds 已提交
1896 1897 1898 1899 1900
	.owner = THIS_MODULE,
	.open = psched_open,
	.read  = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
1901
};
1902 1903 1904 1905 1906

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

1907
	e = proc_create("psched", 0, net->proc_net, &psched_fops);
1908 1909 1910 1911 1912 1913 1914 1915
	if (e == NULL)
		return -ENOMEM;

	return 0;
}

static void __net_exit psched_net_exit(struct net *net)
{
1916
	remove_proc_entry("psched", net->proc_net);
1917 1918 1919 1920 1921 1922 1923 1924 1925 1926
}
#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
1927 1928
#endif

1929 1930 1931 1932 1933
static struct pernet_operations psched_net_ops = {
	.init = psched_net_init,
	.exit = psched_net_exit,
};

L
Linus Torvalds 已提交
1934 1935
static int __init pktsched_init(void)
{
1936 1937 1938 1939
	int err;

	err = register_pernet_subsys(&psched_net_ops);
	if (err) {
E
Eric Dumazet 已提交
1940
		pr_err("pktsched_init: "
1941 1942 1943 1944
		       "cannot initialize per netns operations\n");
		return err;
	}

1945
	register_qdisc(&pfifo_fast_ops);
L
Linus Torvalds 已提交
1946 1947
	register_qdisc(&pfifo_qdisc_ops);
	register_qdisc(&bfifo_qdisc_ops);
1948
	register_qdisc(&pfifo_head_drop_qdisc_ops);
1949
	register_qdisc(&mq_qdisc_ops);
L
Linus Torvalds 已提交
1950

1951 1952 1953 1954 1955 1956
	rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL, NULL);
	rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL, NULL);
	rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc, NULL);
	rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL, NULL);
	rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL, NULL);
	rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass, NULL);
1957

L
Linus Torvalds 已提交
1958 1959 1960 1961
	return 0;
}

subsys_initcall(pktsched_init);