sch_api.c 45.7 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;

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

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

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

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

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

	return q;
}

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

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

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

		ops = qdisc_lookup_default(name);
	}

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

	return ops ? 0 : -ENOENT;
}

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

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

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

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

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

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

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

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

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

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

/* Find queueing discipline by name */

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

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

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

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

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

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static struct qdisc_rate_table *qdisc_rtab_list;

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

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

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

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

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

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

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

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

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

	s = nla_data(tb[TCA_STAB_BASE]);

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

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

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

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

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

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

	return stab;
}

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

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

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

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

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

	return skb->len;

nla_put_failure:
	return -1;
}

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

746
	return 0;
L
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747 748
}

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

   Parameters are passed via opt.
 */

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

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

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

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

942 943
	sch->parent = parent;

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

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

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

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

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

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

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

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

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

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

		return sch;
	}
1021
	/* ops->init() failed, we call ->destroy() like qdisc_create_dflt() */
1022 1023
	if (ops->destroy)
		ops->destroy(sch);
L
Linus Torvalds 已提交
1024 1025
err_out3:
	dev_put(dev);
1026
	kfree((char *) sch - sch->padded);
L
Linus Torvalds 已提交
1027 1028 1029 1030 1031
err_out2:
	module_put(ops->owner);
err_out:
	*errp = err;
	return NULL;
1032 1033

err_out4:
1034
	free_percpu(sch->cpu_bstats);
1035
	free_percpu(sch->cpu_qstats);
1036 1037 1038 1039
	/*
	 * Any broken qdiscs that would require a ops->reset() here?
	 * The qdisc was never in action so it shouldn't be necessary.
	 */
1040
	qdisc_put_stab(rtnl_dereference(sch->stab));
1041 1042 1043
	if (ops->destroy)
		ops->destroy(sch);
	goto err_out3;
L
Linus Torvalds 已提交
1044 1045
}

1046
static int qdisc_change(struct Qdisc *sch, struct nlattr **tca)
L
Linus Torvalds 已提交
1047
{
1048
	struct qdisc_size_table *ostab, *stab = NULL;
1049
	int err = 0;
L
Linus Torvalds 已提交
1050

1051
	if (tca[TCA_OPTIONS]) {
L
Linus Torvalds 已提交
1052 1053
		if (sch->ops->change == NULL)
			return -EINVAL;
1054
		err = sch->ops->change(sch, tca[TCA_OPTIONS]);
L
Linus Torvalds 已提交
1055 1056 1057
		if (err)
			return err;
	}
1058 1059 1060 1061 1062 1063 1064

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

1065 1066 1067
	ostab = rtnl_dereference(sch->stab);
	rcu_assign_pointer(sch->stab, stab);
	qdisc_put_stab(ostab);
1068

1069
	if (tca[TCA_RATE]) {
1070 1071
		/* NB: ignores errors from replace_estimator
		   because change can't be undone. */
1072 1073
		if (sch->flags & TCQ_F_MQROOT)
			goto out;
1074 1075 1076
		gen_replace_estimator(&sch->bstats,
				      sch->cpu_bstats,
				      &sch->rate_est,
1077 1078
				      NULL,
				      qdisc_root_sleeping_running(sch),
1079
				      tca[TCA_RATE]);
1080 1081
	}
out:
L
Linus Torvalds 已提交
1082 1083 1084
	return 0;
}

E
Eric Dumazet 已提交
1085 1086
struct check_loop_arg {
	struct qdisc_walker	w;
L
Linus Torvalds 已提交
1087 1088 1089 1090
	struct Qdisc		*p;
	int			depth;
};

1091 1092
static int check_loop_fn(struct Qdisc *q, unsigned long cl,
			 struct qdisc_walker *w);
L
Linus Torvalds 已提交
1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112

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;
1113
	const struct Qdisc_class_ops *cops = q->ops->cl_ops;
L
Linus Torvalds 已提交
1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128
	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.
 */

1129 1130
static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n,
			struct netlink_ext_ack *extack)
L
Linus Torvalds 已提交
1131
{
1132
	struct net *net = sock_net(skb->sk);
1133
	struct tcmsg *tcm = nlmsg_data(n);
1134
	struct nlattr *tca[TCA_MAX + 1];
L
Linus Torvalds 已提交
1135
	struct net_device *dev;
1136
	u32 clid;
L
Linus Torvalds 已提交
1137 1138 1139 1140
	struct Qdisc *q = NULL;
	struct Qdisc *p = NULL;
	int err;

1141
	if ((n->nlmsg_type != RTM_GETQDISC) &&
1142
	    !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1143 1144
		return -EPERM;

1145
	err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL, extack);
1146 1147 1148
	if (err < 0)
		return err;

1149 1150 1151 1152 1153
	dev = __dev_get_by_index(net, tcm->tcm_ifindex);
	if (!dev)
		return -ENODEV;

	clid = tcm->tcm_parent;
L
Linus Torvalds 已提交
1154 1155 1156
	if (clid) {
		if (clid != TC_H_ROOT) {
			if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) {
E
Eric Dumazet 已提交
1157 1158
				p = qdisc_lookup(dev, TC_H_MAJ(clid));
				if (!p)
L
Linus Torvalds 已提交
1159 1160
					return -ENOENT;
				q = qdisc_leaf(p, clid);
E
Eric Dumazet 已提交
1161 1162
			} else if (dev_ingress_queue(dev)) {
				q = dev_ingress_queue(dev)->qdisc_sleeping;
1163
			}
L
Linus Torvalds 已提交
1164
		} else {
1165
			q = dev->qdisc;
L
Linus Torvalds 已提交
1166 1167 1168 1169 1170 1171 1172
		}
		if (!q)
			return -ENOENT;

		if (tcm->tcm_handle && q->handle != tcm->tcm_handle)
			return -EINVAL;
	} else {
E
Eric Dumazet 已提交
1173 1174
		q = qdisc_lookup(dev, tcm->tcm_handle);
		if (!q)
L
Linus Torvalds 已提交
1175 1176 1177
			return -ENOENT;
	}

1178
	if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
L
Linus Torvalds 已提交
1179 1180 1181 1182 1183 1184 1185
		return -EINVAL;

	if (n->nlmsg_type == RTM_DELQDISC) {
		if (!clid)
			return -EINVAL;
		if (q->handle == 0)
			return -ENOENT;
E
Eric Dumazet 已提交
1186 1187
		err = qdisc_graft(dev, p, skb, n, clid, NULL, q);
		if (err != 0)
L
Linus Torvalds 已提交
1188 1189
			return err;
	} else {
1190
		qdisc_notify(net, skb, n, clid, NULL, q);
L
Linus Torvalds 已提交
1191 1192 1193 1194 1195
	}
	return 0;
}

/*
E
Eric Dumazet 已提交
1196
 * Create/change qdisc.
L
Linus Torvalds 已提交
1197 1198
 */

1199 1200
static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n,
			   struct netlink_ext_ack *extack)
L
Linus Torvalds 已提交
1201
{
1202
	struct net *net = sock_net(skb->sk);
L
Linus Torvalds 已提交
1203
	struct tcmsg *tcm;
1204
	struct nlattr *tca[TCA_MAX + 1];
L
Linus Torvalds 已提交
1205 1206 1207 1208 1209
	struct net_device *dev;
	u32 clid;
	struct Qdisc *q, *p;
	int err;

1210
	if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1211 1212
		return -EPERM;

L
Linus Torvalds 已提交
1213 1214
replay:
	/* Reinit, just in case something touches this. */
1215
	err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL, extack);
1216 1217 1218
	if (err < 0)
		return err;

1219
	tcm = nlmsg_data(n);
L
Linus Torvalds 已提交
1220 1221 1222
	clid = tcm->tcm_parent;
	q = p = NULL;

E
Eric Dumazet 已提交
1223 1224
	dev = __dev_get_by_index(net, tcm->tcm_ifindex);
	if (!dev)
L
Linus Torvalds 已提交
1225 1226
		return -ENODEV;

1227

L
Linus Torvalds 已提交
1228 1229 1230
	if (clid) {
		if (clid != TC_H_ROOT) {
			if (clid != TC_H_INGRESS) {
E
Eric Dumazet 已提交
1231 1232
				p = qdisc_lookup(dev, TC_H_MAJ(clid));
				if (!p)
L
Linus Torvalds 已提交
1233 1234
					return -ENOENT;
				q = qdisc_leaf(p, clid);
E
Eric Dumazet 已提交
1235 1236
			} else if (dev_ingress_queue_create(dev)) {
				q = dev_ingress_queue(dev)->qdisc_sleeping;
L
Linus Torvalds 已提交
1237 1238
			}
		} else {
1239
			q = dev->qdisc;
L
Linus Torvalds 已提交
1240 1241 1242 1243 1244 1245 1246 1247
		}

		/* 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
1248
				if (q && !(n->nlmsg_flags & NLM_F_REPLACE))
L
Linus Torvalds 已提交
1249 1250 1251
					return -EEXIST;
				if (TC_H_MIN(tcm->tcm_handle))
					return -EINVAL;
E
Eric Dumazet 已提交
1252 1253
				q = qdisc_lookup(dev, tcm->tcm_handle);
				if (!q)
L
Linus Torvalds 已提交
1254
					goto create_n_graft;
E
Eric Dumazet 已提交
1255
				if (n->nlmsg_flags & NLM_F_EXCL)
L
Linus Torvalds 已提交
1256
					return -EEXIST;
1257
				if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
L
Linus Torvalds 已提交
1258 1259 1260 1261 1262 1263 1264
					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
1265
				if (!q)
L
Linus Torvalds 已提交
1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286
					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
1287 1288 1289
				if ((n->nlmsg_flags & NLM_F_CREATE) &&
				    (n->nlmsg_flags & NLM_F_REPLACE) &&
				    ((n->nlmsg_flags & NLM_F_EXCL) ||
1290 1291
				     (tca[TCA_KIND] &&
				      nla_strcmp(tca[TCA_KIND], q->ops->id))))
L
Linus Torvalds 已提交
1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303
					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
1304
	if (n->nlmsg_flags & NLM_F_EXCL)
L
Linus Torvalds 已提交
1305
		return -EEXIST;
1306
	if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
L
Linus Torvalds 已提交
1307 1308 1309
		return -EINVAL;
	err = qdisc_change(q, tca);
	if (err == 0)
1310
		qdisc_notify(net, skb, n, clid, NULL, q);
L
Linus Torvalds 已提交
1311 1312 1313
	return err;

create_n_graft:
E
Eric Dumazet 已提交
1314
	if (!(n->nlmsg_flags & NLM_F_CREATE))
L
Linus Torvalds 已提交
1315
		return -ENOENT;
1316 1317 1318 1319 1320 1321 1322 1323
	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 {
1324
		struct netdev_queue *dev_queue;
1325 1326

		if (p && p->ops->cl_ops && p->ops->cl_ops->select_queue)
1327 1328 1329 1330 1331
			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);
1332

1333
		q = qdisc_create(dev, dev_queue, p,
1334
				 tcm->tcm_parent, tcm->tcm_handle,
1335
				 tca, &err);
1336
	}
L
Linus Torvalds 已提交
1337 1338 1339 1340 1341 1342 1343
	if (q == NULL) {
		if (err == -EAGAIN)
			goto replay;
		return err;
	}

graft:
1344 1345 1346 1347 1348
	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
1349
	}
1350

L
Linus Torvalds 已提交
1351 1352 1353 1354
	return 0;
}

static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid,
1355
			 u32 portid, u32 seq, u16 flags, int event)
L
Linus Torvalds 已提交
1356
{
1357
	struct gnet_stats_basic_cpu __percpu *cpu_bstats = NULL;
1358
	struct gnet_stats_queue __percpu *cpu_qstats = NULL;
L
Linus Torvalds 已提交
1359 1360
	struct tcmsg *tcm;
	struct nlmsghdr  *nlh;
1361
	unsigned char *b = skb_tail_pointer(skb);
L
Linus Torvalds 已提交
1362
	struct gnet_dump d;
1363
	struct qdisc_size_table *stab;
1364
	__u32 qlen;
L
Linus Torvalds 已提交
1365

1366
	cond_resched();
1367
	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1368 1369 1370
	if (!nlh)
		goto out_nlmsg_trim;
	tcm = nlmsg_data(nlh);
L
Linus Torvalds 已提交
1371
	tcm->tcm_family = AF_UNSPEC;
1372 1373
	tcm->tcm__pad1 = 0;
	tcm->tcm__pad2 = 0;
1374
	tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
L
Linus Torvalds 已提交
1375 1376 1377
	tcm->tcm_parent = clid;
	tcm->tcm_handle = q->handle;
	tcm->tcm_info = atomic_read(&q->refcnt);
1378 1379
	if (nla_put_string(skb, TCA_KIND, q->ops->id))
		goto nla_put_failure;
L
Linus Torvalds 已提交
1380
	if (q->ops->dump && q->ops->dump(q, skb) < 0)
1381
		goto nla_put_failure;
1382
	qlen = q->q.qlen;
L
Linus Torvalds 已提交
1383

1384 1385
	stab = rtnl_dereference(q->stab);
	if (stab && qdisc_dump_stab(skb, stab) < 0)
1386 1387
		goto nla_put_failure;

1388
	if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
1389
					 NULL, &d, TCA_PAD) < 0)
1390
		goto nla_put_failure;
L
Linus Torvalds 已提交
1391 1392

	if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0)
1393
		goto nla_put_failure;
L
Linus Torvalds 已提交
1394

1395
	if (qdisc_is_percpu_stats(q)) {
1396
		cpu_bstats = q->cpu_bstats;
1397 1398
		cpu_qstats = q->cpu_qstats;
	}
1399

1400 1401
	if (gnet_stats_copy_basic(qdisc_root_sleeping_running(q),
				  &d, cpu_bstats, &q->bstats) < 0 ||
1402
	    gnet_stats_copy_rate_est(&d, &q->rate_est) < 0 ||
1403
	    gnet_stats_copy_queue(&d, cpu_qstats, &q->qstats, qlen) < 0)
1404
		goto nla_put_failure;
1405

L
Linus Torvalds 已提交
1406
	if (gnet_stats_finish_copy(&d) < 0)
1407
		goto nla_put_failure;
1408

1409
	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
L
Linus Torvalds 已提交
1410 1411
	return skb->len;

1412
out_nlmsg_trim:
1413
nla_put_failure:
1414
	nlmsg_trim(skb, b);
L
Linus Torvalds 已提交
1415 1416 1417
	return -1;
}

1418
static bool tc_qdisc_dump_ignore(struct Qdisc *q, bool dump_invisible)
1419
{
1420 1421 1422 1423 1424 1425
	if (q->flags & TCQ_F_BUILTIN)
		return true;
	if ((q->flags & TCQ_F_INVISIBLE) && !dump_invisible)
		return true;

	return false;
1426 1427
}

1428 1429 1430
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
1431 1432
{
	struct sk_buff *skb;
1433
	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
L
Linus Torvalds 已提交
1434 1435 1436 1437 1438

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

1439
	if (old && !tc_qdisc_dump_ignore(old, false)) {
1440
		if (tc_fill_qdisc(skb, old, clid, portid, n->nlmsg_seq,
E
Eric Dumazet 已提交
1441
				  0, RTM_DELQDISC) < 0)
L
Linus Torvalds 已提交
1442 1443
			goto err_out;
	}
1444
	if (new && !tc_qdisc_dump_ignore(new, false)) {
1445
		if (tc_fill_qdisc(skb, new, clid, portid, n->nlmsg_seq,
E
Eric Dumazet 已提交
1446
				  old ? NLM_F_REPLACE : 0, RTM_NEWQDISC) < 0)
L
Linus Torvalds 已提交
1447 1448 1449 1450
			goto err_out;
	}

	if (skb->len)
1451
		return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
E
Eric Dumazet 已提交
1452
				      n->nlmsg_flags & NLM_F_ECHO);
L
Linus Torvalds 已提交
1453 1454 1455 1456 1457 1458

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

1459 1460
static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb,
			      struct netlink_callback *cb,
1461 1462
			      int *q_idx_p, int s_q_idx, bool recur,
			      bool dump_invisible)
1463 1464 1465
{
	int ret = 0, q_idx = *q_idx_p;
	struct Qdisc *q;
1466
	int b;
1467 1468 1469 1470 1471 1472 1473 1474

	if (!root)
		return 0;

	q = root;
	if (q_idx < s_q_idx) {
		q_idx++;
	} else {
1475
		if (!tc_qdisc_dump_ignore(q, dump_invisible) &&
1476
		    tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
1477 1478
				  cb->nlh->nlmsg_seq, NLM_F_MULTI,
				  RTM_NEWQDISC) <= 0)
1479 1480 1481
			goto done;
		q_idx++;
	}
1482

1483 1484 1485 1486 1487 1488 1489
	/* 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)
1490 1491
		goto out;

1492
	hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) {
1493 1494 1495 1496
		if (q_idx < s_q_idx) {
			q_idx++;
			continue;
		}
1497
		if (!tc_qdisc_dump_ignore(q, dump_invisible) &&
1498
		    tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
1499 1500
				  cb->nlh->nlmsg_seq, NLM_F_MULTI,
				  RTM_NEWQDISC) <= 0)
1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512
			goto done;
		q_idx++;
	}

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

L
Linus Torvalds 已提交
1513 1514
static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb)
{
1515
	struct net *net = sock_net(skb->sk);
L
Linus Torvalds 已提交
1516 1517 1518
	int idx, q_idx;
	int s_idx, s_q_idx;
	struct net_device *dev;
1519 1520 1521 1522
	const struct nlmsghdr *nlh = cb->nlh;
	struct tcmsg *tcm = nlmsg_data(nlh);
	struct nlattr *tca[TCA_MAX + 1];
	int err;
L
Linus Torvalds 已提交
1523 1524 1525

	s_idx = cb->args[0];
	s_q_idx = q_idx = cb->args[1];
1526

1527
	idx = 0;
1528
	ASSERT_RTNL();
1529

1530
	err = nlmsg_parse(nlh, sizeof(*tcm), tca, TCA_MAX, NULL, NULL);
1531 1532 1533
	if (err < 0)
		return err;

1534
	for_each_netdev(net, dev) {
1535 1536
		struct netdev_queue *dev_queue;

L
Linus Torvalds 已提交
1537
		if (idx < s_idx)
1538
			goto cont;
L
Linus Torvalds 已提交
1539 1540 1541
		if (idx > s_idx)
			s_q_idx = 0;
		q_idx = 0;
1542

1543
		if (tc_dump_qdisc_root(dev->qdisc, skb, cb, &q_idx, s_q_idx,
1544
				       true, tca[TCA_DUMP_INVISIBLE]) < 0)
1545 1546
			goto done;

1547 1548 1549
		dev_queue = dev_ingress_queue(dev);
		if (dev_queue &&
		    tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb,
1550 1551
				       &q_idx, s_q_idx, false,
				       tca[TCA_DUMP_INVISIBLE]) < 0)
1552 1553
			goto done;

1554 1555
cont:
		idx++;
L
Linus Torvalds 已提交
1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572
	}

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

	return skb->len;
}



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



1573 1574
static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n,
			 struct netlink_ext_ack *extack)
L
Linus Torvalds 已提交
1575
{
1576
	struct net *net = sock_net(skb->sk);
1577
	struct tcmsg *tcm = nlmsg_data(n);
1578
	struct nlattr *tca[TCA_MAX + 1];
L
Linus Torvalds 已提交
1579 1580
	struct net_device *dev;
	struct Qdisc *q = NULL;
1581
	const struct Qdisc_class_ops *cops;
L
Linus Torvalds 已提交
1582 1583
	unsigned long cl = 0;
	unsigned long new_cl;
1584 1585 1586
	u32 portid;
	u32 clid;
	u32 qid;
L
Linus Torvalds 已提交
1587 1588
	int err;

1589
	if ((n->nlmsg_type != RTM_GETTCLASS) &&
1590
	    !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1591 1592
		return -EPERM;

1593
	err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL, extack);
1594 1595 1596
	if (err < 0)
		return err;

1597 1598 1599 1600
	dev = __dev_get_by_index(net, tcm->tcm_ifindex);
	if (!dev)
		return -ENODEV;

L
Linus Torvalds 已提交
1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615
	/*
	   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 */

1616 1617 1618 1619
	portid = tcm->tcm_parent;
	clid = tcm->tcm_handle;
	qid = TC_H_MAJ(clid);

1620 1621
	if (portid != TC_H_ROOT) {
		u32 qid1 = TC_H_MAJ(portid);
L
Linus Torvalds 已提交
1622 1623 1624 1625 1626 1627 1628 1629

		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)
1630
			qid = dev->qdisc->handle;
L
Linus Torvalds 已提交
1631 1632

		/* Now qid is genuine qdisc handle consistent
E
Eric Dumazet 已提交
1633 1634
		 * both with parent and child.
		 *
1635
		 * TC_H_MAJ(portid) still may be unspecified, complete it now.
L
Linus Torvalds 已提交
1636
		 */
1637 1638
		if (portid)
			portid = TC_H_MAKE(qid, portid);
L
Linus Torvalds 已提交
1639 1640
	} else {
		if (qid == 0)
1641
			qid = dev->qdisc->handle;
L
Linus Torvalds 已提交
1642 1643 1644
	}

	/* OK. Locate qdisc */
E
Eric Dumazet 已提交
1645 1646
	q = qdisc_lookup(dev, qid);
	if (!q)
L
Linus Torvalds 已提交
1647 1648 1649 1650 1651 1652 1653 1654 1655
		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) {
1656
		if (portid == TC_H_ROOT)
L
Linus Torvalds 已提交
1657 1658 1659 1660 1661 1662 1663 1664 1665
			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
1666 1667
		if (n->nlmsg_type != RTM_NEWTCLASS ||
		    !(n->nlmsg_flags & NLM_F_CREATE))
L
Linus Torvalds 已提交
1668 1669 1670
			goto out;
	} else {
		switch (n->nlmsg_type) {
1671
		case RTM_NEWTCLASS:
L
Linus Torvalds 已提交
1672
			err = -EEXIST;
E
Eric Dumazet 已提交
1673
			if (n->nlmsg_flags & NLM_F_EXCL)
L
Linus Torvalds 已提交
1674 1675 1676
				goto out;
			break;
		case RTM_DELTCLASS:
1677 1678 1679
			err = -EOPNOTSUPP;
			if (cops->delete)
				err = cops->delete(q, cl);
L
Linus Torvalds 已提交
1680
			if (err == 0)
1681 1682
				tclass_notify(net, skb, n, q, cl,
					      RTM_DELTCLASS);
L
Linus Torvalds 已提交
1683 1684
			goto out;
		case RTM_GETTCLASS:
1685
			err = tclass_notify(net, skb, n, q, cl, RTM_NEWTCLASS);
L
Linus Torvalds 已提交
1686 1687 1688 1689 1690 1691 1692 1693
			goto out;
		default:
			err = -EINVAL;
			goto out;
		}
	}

	new_cl = cl;
1694 1695
	err = -EOPNOTSUPP;
	if (cops->change)
1696
		err = cops->change(q, clid, portid, tca, &new_cl);
L
Linus Torvalds 已提交
1697
	if (err == 0)
1698
		tclass_notify(net, skb, n, q, new_cl, RTM_NEWTCLASS);
L
Linus Torvalds 已提交
1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709

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

	return err;
}


static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q,
			  unsigned long cl,
1710
			  u32 portid, u32 seq, u16 flags, int event)
L
Linus Torvalds 已提交
1711 1712 1713
{
	struct tcmsg *tcm;
	struct nlmsghdr  *nlh;
1714
	unsigned char *b = skb_tail_pointer(skb);
L
Linus Torvalds 已提交
1715
	struct gnet_dump d;
1716
	const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops;
L
Linus Torvalds 已提交
1717

1718
	cond_resched();
1719
	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1720 1721 1722
	if (!nlh)
		goto out_nlmsg_trim;
	tcm = nlmsg_data(nlh);
L
Linus Torvalds 已提交
1723
	tcm->tcm_family = AF_UNSPEC;
1724 1725
	tcm->tcm__pad1 = 0;
	tcm->tcm__pad2 = 0;
1726
	tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
L
Linus Torvalds 已提交
1727 1728 1729
	tcm->tcm_parent = q->handle;
	tcm->tcm_handle = q->handle;
	tcm->tcm_info = 0;
1730 1731
	if (nla_put_string(skb, TCA_KIND, q->ops->id))
		goto nla_put_failure;
L
Linus Torvalds 已提交
1732
	if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0)
1733
		goto nla_put_failure;
L
Linus Torvalds 已提交
1734

1735
	if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
1736
					 NULL, &d, TCA_PAD) < 0)
1737
		goto nla_put_failure;
L
Linus Torvalds 已提交
1738 1739

	if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0)
1740
		goto nla_put_failure;
L
Linus Torvalds 已提交
1741 1742

	if (gnet_stats_finish_copy(&d) < 0)
1743
		goto nla_put_failure;
L
Linus Torvalds 已提交
1744

1745
	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
L
Linus Torvalds 已提交
1746 1747
	return skb->len;

1748
out_nlmsg_trim:
1749
nla_put_failure:
1750
	nlmsg_trim(skb, b);
L
Linus Torvalds 已提交
1751 1752 1753
	return -1;
}

1754 1755 1756
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
1757 1758
{
	struct sk_buff *skb;
1759
	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
L
Linus Torvalds 已提交
1760 1761 1762 1763 1764

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

1765
	if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, event) < 0) {
L
Linus Torvalds 已提交
1766 1767 1768 1769
		kfree_skb(skb);
		return -EINVAL;
	}

1770
	return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
E
Eric Dumazet 已提交
1771
			      n->nlmsg_flags & NLM_F_ECHO);
L
Linus Torvalds 已提交
1772 1773
}

E
Eric Dumazet 已提交
1774 1775 1776 1777
struct qdisc_dump_args {
	struct qdisc_walker	w;
	struct sk_buff		*skb;
	struct netlink_callback	*cb;
L
Linus Torvalds 已提交
1778 1779
};

1780 1781
static int qdisc_class_dump(struct Qdisc *q, unsigned long cl,
			    struct qdisc_walker *arg)
L
Linus Torvalds 已提交
1782 1783 1784
{
	struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg;

1785
	return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).portid,
1786 1787
			      a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
			      RTM_NEWTCLASS);
L
Linus Torvalds 已提交
1788 1789
}

1790 1791 1792 1793 1794 1795
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;

1796
	if (tc_qdisc_dump_ignore(q, false) ||
1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823
	    *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;
1824
	int b;
1825 1826 1827 1828 1829 1830 1831

	if (!root)
		return 0;

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

1832 1833 1834
	if (!qdisc_dev(root))
		return 0;

1835 1836 1837 1838 1839 1840
	if (tcm->tcm_parent) {
		q = qdisc_match_from_root(root, TC_H_MAJ(tcm->tcm_parent));
		if (q && tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0)
			return -1;
		return 0;
	}
1841
	hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) {
1842 1843 1844 1845 1846 1847 1848
		if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0)
			return -1;
	}

	return 0;
}

L
Linus Torvalds 已提交
1849 1850
static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb)
{
1851
	struct tcmsg *tcm = nlmsg_data(cb->nlh);
1852
	struct net *net = sock_net(skb->sk);
1853
	struct netdev_queue *dev_queue;
L
Linus Torvalds 已提交
1854
	struct net_device *dev;
1855
	int t, s_t;
L
Linus Torvalds 已提交
1856

1857
	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
L
Linus Torvalds 已提交
1858
		return 0;
E
Eric Dumazet 已提交
1859 1860
	dev = dev_get_by_index(net, tcm->tcm_ifindex);
	if (!dev)
L
Linus Torvalds 已提交
1861 1862 1863 1864 1865
		return 0;

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

1866
	if (tc_dump_tclass_root(dev->qdisc, skb, tcm, cb, &t, s_t) < 0)
1867 1868
		goto done;

1869 1870 1871 1872
	dev_queue = dev_ingress_queue(dev);
	if (dev_queue &&
	    tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb,
				&t, s_t) < 0)
1873
		goto done;
L
Linus Torvalds 已提交
1874

1875
done:
L
Linus Torvalds 已提交
1876 1877 1878 1879 1880 1881 1882 1883 1884 1885
	cb->args[0] = t;

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

#ifdef CONFIG_PROC_FS
static int psched_show(struct seq_file *seq, void *v)
{
	seq_printf(seq, "%08x %08x %08x %08x\n",
1886
		   (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1),
1887
		   1000000,
1888
		   (u32)NSEC_PER_SEC / hrtimer_resolution);
L
Linus Torvalds 已提交
1889 1890 1891 1892 1893 1894

	return 0;
}

static int psched_open(struct inode *inode, struct file *file)
{
1895
	return single_open(file, psched_show, NULL);
L
Linus Torvalds 已提交
1896 1897
}

1898
static const struct file_operations psched_fops = {
L
Linus Torvalds 已提交
1899 1900 1901 1902 1903
	.owner = THIS_MODULE,
	.open = psched_open,
	.read  = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
1904
};
1905 1906 1907 1908 1909

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

1910
	e = proc_create("psched", 0, net->proc_net, &psched_fops);
1911 1912 1913 1914 1915 1916 1917 1918
	if (e == NULL)
		return -ENOMEM;

	return 0;
}

static void __net_exit psched_net_exit(struct net *net)
{
1919
	remove_proc_entry("psched", net->proc_net);
1920 1921 1922 1923 1924 1925 1926 1927 1928 1929
}
#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
1930 1931
#endif

1932 1933 1934 1935 1936
static struct pernet_operations psched_net_ops = {
	.init = psched_net_init,
	.exit = psched_net_exit,
};

L
Linus Torvalds 已提交
1937 1938
static int __init pktsched_init(void)
{
1939 1940 1941 1942
	int err;

	err = register_pernet_subsys(&psched_net_ops);
	if (err) {
E
Eric Dumazet 已提交
1943
		pr_err("pktsched_init: "
1944 1945 1946 1947
		       "cannot initialize per netns operations\n");
		return err;
	}

1948
	register_qdisc(&pfifo_fast_ops);
L
Linus Torvalds 已提交
1949 1950
	register_qdisc(&pfifo_qdisc_ops);
	register_qdisc(&bfifo_qdisc_ops);
1951
	register_qdisc(&pfifo_head_drop_qdisc_ops);
1952
	register_qdisc(&mq_qdisc_ops);
1953
	register_qdisc(&noqueue_qdisc_ops);
L
Linus Torvalds 已提交
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);
1957 1958
	rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc,
		      NULL);
1959 1960
	rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL, NULL);
	rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL, NULL);
1961 1962
	rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass,
		      NULL);
1963

L
Linus Torvalds 已提交
1964 1965 1966 1967
	return 0;
}

subsys_initcall(pktsched_init);
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