Initial import

1 files changed, 1970 insertions, 0 deletions

diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
new file mode 100644
index 000000000..1e1c89e51
--- /dev/null
+++ b/net/sched/sch_api.c
@@ -0,0 +1,1970 @@
+/*
+ * 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>
+#include <linux/hrtimer.h>
+#include <linux/lockdep.h>
+#include <linux/slab.h>
+
+#include <net/net_namespace.h>
+#include <net/sock.h>
+#include <net/netlink.h>
+#include <net/pkt_sched.h>
+
+static int qdisc_notify(struct net *net, struct sk_buff *oskb,
+			struct nlmsghdr *n, u32 clid,
+			struct Qdisc *old, struct Qdisc *new);
+static int tclass_notify(struct net *net, struct sk_buff *oskb,
+			 struct nlmsghdr *n, struct Qdisc *q,
+			 unsigned long cl, int event);
+
+/*
+
+   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:
+
+   ---peek
+
+   like dequeue but without removing a packet from the queue
+
+   ---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;
+
+/* Register/unregister queueing discipline */
+
+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;
+	if (qops->peek == NULL) {
+		if (qops->dequeue == NULL)
+			qops->peek = noop_qdisc_ops.peek;
+		else
+			goto out_einval;
+	}
+	if (qops->dequeue == NULL)
+		qops->dequeue = noop_qdisc_ops.dequeue;
+
+	if (qops->cl_ops) {
+		const struct Qdisc_class_ops *cops = qops->cl_ops;
+
+		if (!(cops->get && cops->put && cops->walk && cops->leaf))
+			goto out_einval;
+
+		if (cops->tcf_chain && !(cops->bind_tcf && cops->unbind_tcf))
+			goto out_einval;
+	}
+
+	qops->next = NULL;
+	*qp = qops;
+	rc = 0;
+out:
+	write_unlock(&qdisc_mod_lock);
+	return rc;
+
+out_einval:
+	rc = -EINVAL;
+	goto out;
+}
+EXPORT_SYMBOL(register_qdisc);
+
+int unregister_qdisc(struct Qdisc_ops *qops)
+{
+	struct Qdisc_ops *q, **qp;
+	int err = -ENOENT;
+
+	write_lock(&qdisc_mod_lock);
+	for (qp = &qdisc_base; (q = *qp) != NULL; qp = &q->next)
+		if (q == qops)
+			break;
+	if (q) {
+		*qp = q->next;
+		q->next = NULL;
+		err = 0;
+	}
+	write_unlock(&qdisc_mod_lock);
+	return err;
+}
+EXPORT_SYMBOL(unregister_qdisc);
+
+/* 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;
+}
+
+/* We know handle. Find qdisc among all qdisc's attached to device
+   (root qdisc, all its children, children of children etc.)
+ */
+
+static struct Qdisc *qdisc_match_from_root(struct Qdisc *root, u32 handle)
+{
+	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;
+}
+
+void qdisc_list_add(struct Qdisc *q)
+{
+	if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) {
+		struct Qdisc *root = qdisc_dev(q)->qdisc;
+
+		WARN_ON_ONCE(root == &noop_qdisc);
+		list_add_tail(&q->list, &root->list);
+	}
+}
+EXPORT_SYMBOL(qdisc_list_add);
+
+void qdisc_list_del(struct Qdisc *q)
+{
+	if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS))
+		list_del(&q->list);
+}
+EXPORT_SYMBOL(qdisc_list_del);
+
+struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle)
+{
+	struct Qdisc *q;
+
+	q = qdisc_match_from_root(dev->qdisc, handle);
+	if (q)
+		goto out;
+
+	if (dev_ingress_queue(dev))
+		q = qdisc_match_from_root(
+			dev_ingress_queue(dev)->qdisc_sleeping,
+			handle);
+out:
+	return q;
+}
+
+static struct Qdisc *qdisc_leaf(struct Qdisc *p, u32 classid)
+{
+	unsigned long cl;
+	struct Qdisc *leaf;
+	const struct Qdisc_class_ops *cops = p->ops->cl_ops;
+
+	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 */
+
+static struct Qdisc_ops *qdisc_lookup_ops(struct nlattr *kind)
+{
+	struct Qdisc_ops *q = NULL;
+
+	if (kind) {
+		read_lock(&qdisc_mod_lock);
+		for (q = qdisc_base; q; q = q->next) {
+			if (nla_strcmp(kind, q->id) == 0) {
+				if (!try_module_get(q->owner))
+					q = NULL;
+				break;
+			}
+		}
+		read_unlock(&qdisc_mod_lock);
+	}
+	return q;
+}
+
+/* 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;
+}
+
+static struct qdisc_rate_table *qdisc_rtab_list;
+
+struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r, struct nlattr *tab)
+{
+	struct qdisc_rate_table *rtab;
+
+	if (tab == NULL || r->rate == 0 || r->cell_log == 0 ||
+	    nla_len(tab) != TC_RTAB_SIZE)
+		return NULL;
+
+	for (rtab = qdisc_rtab_list; rtab; rtab = rtab->next) {
+		if (!memcmp(&rtab->rate, r, sizeof(struct tc_ratespec)) &&
+		    !memcmp(&rtab->data, nla_data(tab), 1024)) {
+			rtab->refcnt++;
+			return rtab;
+		}
+	}
+
+	rtab = kmalloc(sizeof(*rtab), GFP_KERNEL);
+	if (rtab) {
+		rtab->rate = *r;
+		rtab->refcnt = 1;
+		memcpy(rtab->data, nla_data(tab), 1024);
+		if (r->linklayer == TC_LINKLAYER_UNAWARE)
+			r->linklayer = __detect_linklayer(r, rtab->data);
+		rtab->next = qdisc_rtab_list;
+		qdisc_rtab_list = rtab;
+	}
+	return rtab;
+}
+EXPORT_SYMBOL(qdisc_get_rtab);
+
+void qdisc_put_rtab(struct qdisc_rate_table *tab)
+{
+	struct qdisc_rate_table *rtab, **rtabp;
+
+	if (!tab || --tab->refcnt)
+		return;
+
+	for (rtabp = &qdisc_rtab_list;
+	     (rtab = *rtabp) != NULL;
+	     rtabp = &rtab->next) {
+		if (rtab == tab) {
+			*rtabp = rtab->next;
+			kfree(rtab);
+			return;
+		}
+	}
+}
+EXPORT_SYMBOL(qdisc_put_rtab);
+
+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);
+	}
+
+	if (tsize != s->tsize || (!tab && tsize > 0))
+		return ERR_PTR(-EINVAL);
+
+	spin_lock(&qdisc_stab_lock);
+
+	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++;
+		spin_unlock(&qdisc_stab_lock);
+		return stab;
+	}
+
+	spin_unlock(&qdisc_stab_lock);
+
+	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));
+
+	spin_lock(&qdisc_stab_lock);
+	list_add_tail(&stab->list, &qdisc_stab_list);
+	spin_unlock(&qdisc_stab_lock);
+
+	return stab;
+}
+
+static void stab_kfree_rcu(struct rcu_head *head)
+{
+	kfree(container_of(head, struct qdisc_size_table, rcu));
+}
+
+void qdisc_put_stab(struct qdisc_size_table *tab)
+{
+	if (!tab)
+		return;
+
+	spin_lock(&qdisc_stab_lock);
+
+	if (--tab->refcnt == 0) {
+		list_del(&tab->list);
+		call_rcu_bh(&tab->rcu, stab_kfree_rcu);
+	}
+
+	spin_unlock(&qdisc_stab_lock);
+}
+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);
+	if (nest == NULL)
+		goto nla_put_failure;
+	if (nla_put(skb, TCA_STAB_BASE, sizeof(stab->szopts), &stab->szopts))
+		goto nla_put_failure;
+	nla_nest_end(skb, nest);
+
+	return skb->len;
+
+nla_put_failure:
+	return -1;
+}
+
+void __qdisc_calculate_pkt_len(struct sk_buff *skb, const struct qdisc_size_table *stab)
+{
+	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;
+}
+EXPORT_SYMBOL(__qdisc_calculate_pkt_len);
+
+void qdisc_warn_nonwc(const char *txt, struct Qdisc *qdisc)
+{
+	if (!(qdisc->flags & TCQ_F_WARN_NONWC)) {
+		pr_warn("%s: %s qdisc %X: is non-work-conserving?\n",
+			txt, qdisc->ops->id, qdisc->handle >> 16);
+		qdisc->flags |= TCQ_F_WARN_NONWC;
+	}
+}
+EXPORT_SYMBOL(qdisc_warn_nonwc);
+
+static enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer)
+{
+	struct qdisc_watchdog *wd = container_of(timer, struct qdisc_watchdog,
+						 timer);
+
+	rcu_read_lock();
+	qdisc_unthrottled(wd->qdisc);
+	__netif_schedule(qdisc_root(wd->qdisc));
+	rcu_read_unlock();
+
+	return HRTIMER_NORESTART;
+}
+
+void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc)
+{
+	hrtimer_init(&wd->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED);
+	wd->timer.function = qdisc_watchdog;
+	wd->qdisc = qdisc;
+}
+EXPORT_SYMBOL(qdisc_watchdog_init);
+
+void qdisc_watchdog_schedule_ns(struct qdisc_watchdog *wd, u64 expires, bool throttle)
+{
+	if (test_bit(__QDISC_STATE_DEACTIVATED,
+		     &qdisc_root_sleeping(wd->qdisc)->state))
+		return;
+
+	if (throttle)
+		qdisc_throttled(wd->qdisc);
+
+	hrtimer_start(&wd->timer,
+		      ns_to_ktime(expires),
+		      HRTIMER_MODE_ABS_PINNED);
+}
+EXPORT_SYMBOL(qdisc_watchdog_schedule_ns);
+
+void qdisc_watchdog_cancel(struct qdisc_watchdog *wd)
+{
+	hrtimer_cancel(&wd->timer);
+	qdisc_unthrottled(wd->qdisc);
+}
+EXPORT_SYMBOL(qdisc_watchdog_cancel);
+
+static struct hlist_head *qdisc_class_hash_alloc(unsigned int n)
+{
+	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;
+	struct hlist_node *next;
+	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++) {
+		hlist_for_each_entry_safe(cl, next, &ohash[i], hnode) {
+			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);
+
+/* Allocate an unique handle from space managed by kernel
+ * Possible range is [8000-FFFF]:0000 (0x8000 values)
+ */
+static u32 qdisc_alloc_handle(struct net_device *dev)
+{
+	int i = 0x8000;
+	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);
+		if (!qdisc_lookup(dev, autohandle))
+			return autohandle;
+		cond_resched();
+	} while	(--i > 0);
+
+	return 0;
+}
+
+void qdisc_tree_decrease_qlen(struct Qdisc *sch, unsigned int n)
+{
+	const struct Qdisc_class_ops *cops;
+	unsigned long cl;
+	u32 parentid;
+	int drops;
+
+	if (n == 0)
+		return;
+	drops = max_t(int, n, 0);
+	while ((parentid = sch->parent)) {
+		if (TC_H_MAJ(parentid) == TC_H_MAJ(TC_H_INGRESS))
+			return;
+
+		sch = qdisc_lookup(qdisc_dev(sch), TC_H_MAJ(parentid));
+		if (sch == NULL) {
+			WARN_ON(parentid != TC_H_ROOT);
+			return;
+		}
+		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;
+		__qdisc_qstats_drop(sch, drops);
+	}
+}
+EXPORT_SYMBOL(qdisc_tree_decrease_qlen);
+
+static void notify_and_destroy(struct net *net, struct sk_buff *skb,
+			       struct nlmsghdr *n, u32 clid,
+			       struct Qdisc *old, struct Qdisc *new)
+{
+	if (new || old)
+		qdisc_notify(net, skb, n, clid, old, new);
+
+	if (old)
+		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.
+ */
+
+static int qdisc_graft(struct net_device *dev, struct Qdisc *parent,
+		       struct sk_buff *skb, struct nlmsghdr *n, u32 classid,
+		       struct Qdisc *new, struct Qdisc *old)
+{
+	struct Qdisc *q = old;
+	struct net *net = dev_net(dev);
+	int err = 0;
+
+	if (parent == NULL) {
+		unsigned int i, num_q, ingress;
+
+		ingress = 0;
+		num_q = dev->num_tx_queues;
+		if ((q && q->flags & TCQ_F_INGRESS) ||
+		    (new && new->flags & TCQ_F_INGRESS)) {
+			num_q = 1;
+			ingress = 1;
+			if (!dev_ingress_queue(dev))
+				return -ENOENT;
+		}
+
+		if (dev->flags & IFF_UP)
+			dev_deactivate(dev);
+
+		if (new && new->ops->attach)
+			goto skip;
+
+		for (i = 0; i < num_q; i++) {
+			struct netdev_queue *dev_queue = dev_ingress_queue(dev);
+
+			if (!ingress)
+				dev_queue = netdev_get_tx_queue(dev, i);
+
+			old = dev_graft_qdisc(dev_queue, new);
+			if (new && i > 0)
+				atomic_inc(&new->refcnt);
+
+			if (!ingress)
+				qdisc_destroy(old);
+		}
+
+skip:
+		if (!ingress) {
+			notify_and_destroy(net, skb, n, classid,
+					   dev->qdisc, new);
+			if (new && !new->ops->attach)
+				atomic_inc(&new->refcnt);
+			dev->qdisc = new ? : &noop_qdisc;
+
+			if (new && new->ops->attach)
+				new->ops->attach(new);
+		} else {
+			notify_and_destroy(net, skb, n, classid, old, new);
+		}
+
+		if (dev->flags & IFF_UP)
+			dev_activate(dev);
+	} else {
+		const struct Qdisc_class_ops *cops = parent->ops->cl_ops;
+
+		err = -EOPNOTSUPP;
+		if (cops && cops->graft) {
+			unsigned long cl = cops->get(parent, classid);
+			if (cl) {
+				err = cops->graft(parent, cl, new, &old);
+				cops->put(parent, cl);
+			} else
+				err = -ENOENT;
+		}
+		if (!err)
+			notify_and_destroy(net, skb, n, classid, old, new);
+	}
+	return err;
+}
+
+/* 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;
+
+/*
+   Allocate and initialize new qdisc.
+
+   Parameters are passed via opt.
+ */
+
+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)
+{
+	int err;
+	struct nlattr *kind = tca[TCA_KIND];
+	struct Qdisc *sch;
+	struct Qdisc_ops *ops;
+	struct qdisc_size_table *stab;
+
+	ops = qdisc_lookup_ops(kind);
+#ifdef CONFIG_MODULES
+	if (ops == NULL && kind != NULL) {
+		char name[IFNAMSIZ];
+		if (nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) {
+			/* 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
+
+	err = -ENOENT;
+	if (ops == NULL)
+		goto err_out;
+
+	sch = qdisc_alloc(dev_queue, ops);
+	if (IS_ERR(sch)) {
+		err = PTR_ERR(sch);
+		goto err_out2;
+	}
+
+	sch->parent = parent;
+
+	if (handle == TC_H_INGRESS) {
+		sch->flags |= TCQ_F_INGRESS;
+		handle = TC_H_MAKE(TC_H_INGRESS, 0);
+		lockdep_set_class(qdisc_lock(sch), &qdisc_rx_lock);
+	} else {
+		if (handle == 0) {
+			handle = qdisc_alloc_handle(dev);
+			err = -ENOMEM;
+			if (handle == 0)
+				goto err_out3;
+		}
+		lockdep_set_class(qdisc_lock(sch), &qdisc_tx_lock);
+		if (!netif_is_multiqueue(dev))
+			sch->flags |= TCQ_F_ONETXQUEUE;
+	}
+
+	sch->handle = handle;
+
+	if (!ops->init || (err = ops->init(sch, tca[TCA_OPTIONS])) == 0) {
+		if (qdisc_is_percpu_stats(sch)) {
+			sch->cpu_bstats =
+				netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu);
+			if (!sch->cpu_bstats)
+				goto err_out4;
+
+			sch->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
+			if (!sch->cpu_qstats)
+				goto err_out4;
+		}
+
+		if (tca[TCA_STAB]) {
+			stab = qdisc_get_stab(tca[TCA_STAB]);
+			if (IS_ERR(stab)) {
+				err = PTR_ERR(stab);
+				goto err_out4;
+			}
+			rcu_assign_pointer(sch->stab, stab);
+		}
+		if (tca[TCA_RATE]) {
+			spinlock_t *root_lock;
+
+			err = -EOPNOTSUPP;
+			if (sch->flags & TCQ_F_MQROOT)
+				goto err_out4;
+
+			if ((sch->parent != TC_H_ROOT) &&
+			    !(sch->flags & TCQ_F_INGRESS) &&
+			    (!p || !(p->flags & TCQ_F_MQROOT)))
+				root_lock = qdisc_root_sleeping_lock(sch);
+			else
+				root_lock = qdisc_lock(sch);
+
+			err = gen_new_estimator(&sch->bstats,
+						sch->cpu_bstats,
+						&sch->rate_est,
+						root_lock,
+						tca[TCA_RATE]);
+			if (err)
+				goto err_out4;
+		}
+
+		qdisc_list_add(sch);
+
+		return sch;
+	}
+err_out3:
+	dev_put(dev);
+	kfree((char *) sch - sch->padded);
+err_out2:
+	module_put(ops->owner);
+err_out:
+	*errp = err;
+	return NULL;
+
+err_out4:
+	free_percpu(sch->cpu_bstats);
+	free_percpu(sch->cpu_qstats);
+	/*
+	 * Any broken qdiscs that would require a ops->reset() here?
+	 * The qdisc was never in action so it shouldn't be necessary.
+	 */
+	qdisc_put_stab(rtnl_dereference(sch->stab));
+	if (ops->destroy)
+		ops->destroy(sch);
+	goto err_out3;
+}
+
+static int qdisc_change(struct Qdisc *sch, struct nlattr **tca)
+{
+	struct qdisc_size_table *ostab, *stab = NULL;
+	int err = 0;
+
+	if (tca[TCA_OPTIONS]) {
+		if (sch->ops->change == NULL)
+			return -EINVAL;
+		err = sch->ops->change(sch, tca[TCA_OPTIONS]);
+		if (err)
+			return err;
+	}
+
+	if (tca[TCA_STAB]) {
+		stab = qdisc_get_stab(tca[TCA_STAB]);
+		if (IS_ERR(stab))
+			return PTR_ERR(stab);
+	}
+
+	ostab = rtnl_dereference(sch->stab);
+	rcu_assign_pointer(sch->stab, stab);
+	qdisc_put_stab(ostab);
+
+	if (tca[TCA_RATE]) {
+		/* NB: ignores errors from replace_estimator
+		   because change can't be undone. */
+		if (sch->flags & TCQ_F_MQROOT)
+			goto out;
+		gen_replace_estimator(&sch->bstats,
+				      sch->cpu_bstats,
+				      &sch->rate_est,
+				      qdisc_root_sleeping_lock(sch),
+				      tca[TCA_RATE]);
+	}
+out:
+	return 0;
+}
+
+struct check_loop_arg {
+	struct qdisc_walker	w;
+	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;
+	const struct Qdisc_class_ops *cops = q->ops->cl_ops;
+	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.
+ */
+
+static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n)
+{
+	struct net *net = sock_net(skb->sk);
+	struct tcmsg *tcm = nlmsg_data(n);
+	struct nlattr *tca[TCA_MAX + 1];
+	struct net_device *dev;
+	u32 clid;
+	struct Qdisc *q = NULL;
+	struct Qdisc *p = NULL;
+	int err;
+
+	if ((n->nlmsg_type != RTM_GETQDISC) &&
+	    !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
+		return -EPERM;
+
+	err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
+	if (err < 0)
+		return err;
+
+	dev = __dev_get_by_index(net, tcm->tcm_ifindex);
+	if (!dev)
+		return -ENODEV;
+
+	clid = tcm->tcm_parent;
+	if (clid) {
+		if (clid != TC_H_ROOT) {
+			if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) {
+				p = qdisc_lookup(dev, TC_H_MAJ(clid));
+				if (!p)
+					return -ENOENT;
+				q = qdisc_leaf(p, clid);
+			} else if (dev_ingress_queue(dev)) {
+				q = dev_ingress_queue(dev)->qdisc_sleeping;
+			}
+		} else {
+			q = dev->qdisc;
+		}
+		if (!q)
+			return -ENOENT;
+
+		if (tcm->tcm_handle && q->handle != tcm->tcm_handle)
+			return -EINVAL;
+	} else {
+		q = qdisc_lookup(dev, tcm->tcm_handle);
+		if (!q)
+			return -ENOENT;
+	}
+
+	if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
+		return -EINVAL;
+
+	if (n->nlmsg_type == RTM_DELQDISC) {
+		if (!clid)
+			return -EINVAL;
+		if (q->handle == 0)
+			return -ENOENT;
+		err = qdisc_graft(dev, p, skb, n, clid, NULL, q);
+		if (err != 0)
+			return err;
+	} else {
+		qdisc_notify(net, skb, n, clid, NULL, q);
+	}
+	return 0;
+}
+
+/*
+ * Create/change qdisc.
+ */
+
+static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n)
+{
+	struct net *net = sock_net(skb->sk);
+	struct tcmsg *tcm;
+	struct nlattr *tca[TCA_MAX + 1];
+	struct net_device *dev;
+	u32 clid;
+	struct Qdisc *q, *p;
+	int err;
+
+	if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
+		return -EPERM;
+
+replay:
+	/* Reinit, just in case something touches this. */
+	err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
+	if (err < 0)
+		return err;
+
+	tcm = nlmsg_data(n);
+	clid = tcm->tcm_parent;
+	q = p = NULL;
+
+	dev = __dev_get_by_index(net, tcm->tcm_ifindex);
+	if (!dev)
+		return -ENODEV;
+
+
+	if (clid) {
+		if (clid != TC_H_ROOT) {
+			if (clid != TC_H_INGRESS) {
+				p = qdisc_lookup(dev, TC_H_MAJ(clid));
+				if (!p)
+					return -ENOENT;
+				q = qdisc_leaf(p, clid);
+			} else if (dev_ingress_queue_create(dev)) {
+				q = dev_ingress_queue(dev)->qdisc_sleeping;
+			}
+		} else {
+			q = dev->qdisc;
+		}
+
+		/* 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) {
+				if (q && !(n->nlmsg_flags & NLM_F_REPLACE))
+					return -EEXIST;
+				if (TC_H_MIN(tcm->tcm_handle))
+					return -EINVAL;
+				q = qdisc_lookup(dev, tcm->tcm_handle);
+				if (!q)
+					goto create_n_graft;
+				if (n->nlmsg_flags & NLM_F_EXCL)
+					return -EEXIST;
+				if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
+					return -EINVAL;
+				if (q == p ||
+				    (p && check_loop(q, p, 0)))
+					return -ELOOP;
+				atomic_inc(&q->refcnt);
+				goto graft;
+			} else {
+				if (!q)
+					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.
+				 */
+				if ((n->nlmsg_flags & NLM_F_CREATE) &&
+				    (n->nlmsg_flags & NLM_F_REPLACE) &&
+				    ((n->nlmsg_flags & NLM_F_EXCL) ||
+				     (tca[TCA_KIND] &&
+				      nla_strcmp(tca[TCA_KIND], q->ops->id))))
+					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;
+	if (n->nlmsg_flags & NLM_F_EXCL)
+		return -EEXIST;
+	if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
+		return -EINVAL;
+	err = qdisc_change(q, tca);
+	if (err == 0)
+		qdisc_notify(net, skb, n, clid, NULL, q);
+	return err;
+
+create_n_graft:
+	if (!(n->nlmsg_flags & NLM_F_CREATE))
+		return -ENOENT;
+	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 {
+		struct netdev_queue *dev_queue;
+
+		if (p && p->ops->cl_ops && p->ops->cl_ops->select_queue)
+			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);
+
+		q = qdisc_create(dev, dev_queue, p,
+				 tcm->tcm_parent, tcm->tcm_handle,
+				 tca, &err);
+	}
+	if (q == NULL) {
+		if (err == -EAGAIN)
+			goto replay;
+		return err;
+	}
+
+graft:
+	err = qdisc_graft(dev, p, skb, n, clid, q, NULL);
+	if (err) {
+		if (q)
+			qdisc_destroy(q);
+		return err;
+	}
+
+	return 0;
+}
+
+static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid,
+			 u32 portid, u32 seq, u16 flags, int event)
+{
+	struct gnet_stats_basic_cpu __percpu *cpu_bstats = NULL;
+	struct gnet_stats_queue __percpu *cpu_qstats = NULL;
+	struct tcmsg *tcm;
+	struct nlmsghdr  *nlh;
+	unsigned char *b = skb_tail_pointer(skb);
+	struct gnet_dump d;
+	struct qdisc_size_table *stab;
+	__u32 qlen;
+
+	cond_resched();
+	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
+	if (!nlh)
+		goto out_nlmsg_trim;
+	tcm = nlmsg_data(nlh);
+	tcm->tcm_family = AF_UNSPEC;
+	tcm->tcm__pad1 = 0;
+	tcm->tcm__pad2 = 0;
+	tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
+	tcm->tcm_parent = clid;
+	tcm->tcm_handle = q->handle;
+	tcm->tcm_info = atomic_read(&q->refcnt);
+	if (nla_put_string(skb, TCA_KIND, q->ops->id))
+		goto nla_put_failure;
+	if (q->ops->dump && q->ops->dump(q, skb) < 0)
+		goto nla_put_failure;
+	qlen = q->q.qlen;
+
+	stab = rtnl_dereference(q->stab);
+	if (stab && qdisc_dump_stab(skb, stab) < 0)
+		goto nla_put_failure;
+
+	if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
+					 qdisc_root_sleeping_lock(q), &d) < 0)
+		goto nla_put_failure;
+
+	if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0)
+		goto nla_put_failure;
+
+	if (qdisc_is_percpu_stats(q)) {
+		cpu_bstats = q->cpu_bstats;
+		cpu_qstats = q->cpu_qstats;
+	}
+
+	if (gnet_stats_copy_basic(&d, cpu_bstats, &q->bstats) < 0 ||
+	    gnet_stats_copy_rate_est(&d, &q->bstats, &q->rate_est) < 0 ||
+	    gnet_stats_copy_queue(&d, cpu_qstats, &q->qstats, qlen) < 0)
+		goto nla_put_failure;
+
+	if (gnet_stats_finish_copy(&d) < 0)
+		goto nla_put_failure;
+
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
+	return skb->len;
+
+out_nlmsg_trim:
+nla_put_failure:
+	nlmsg_trim(skb, b);
+	return -1;
+}
+
+static bool tc_qdisc_dump_ignore(struct Qdisc *q)
+{
+	return (q->flags & TCQ_F_BUILTIN) ? true : false;
+}
+
+static int qdisc_notify(struct net *net, struct sk_buff *oskb,
+			struct nlmsghdr *n, u32 clid,
+			struct Qdisc *old, struct Qdisc *new)
+{
+	struct sk_buff *skb;
+	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
+
+	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
+	if (!skb)
+		return -ENOBUFS;
+
+	if (old && !tc_qdisc_dump_ignore(old)) {
+		if (tc_fill_qdisc(skb, old, clid, portid, n->nlmsg_seq,
+				  0, RTM_DELQDISC) < 0)
+			goto err_out;
+	}
+	if (new && !tc_qdisc_dump_ignore(new)) {
+		if (tc_fill_qdisc(skb, new, clid, portid, n->nlmsg_seq,
+				  old ? NLM_F_REPLACE : 0, RTM_NEWQDISC) < 0)
+			goto err_out;
+	}
+
+	if (skb->len)
+		return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
+				      n->nlmsg_flags & NLM_F_ECHO);
+
+err_out:
+	kfree_skb(skb);
+	return -EINVAL;
+}
+
+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) &&
+		    tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
+				  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;
+		}
+		if (!tc_qdisc_dump_ignore(q) &&
+		    tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
+				  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;
+}
+
+static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	struct net *net = sock_net(skb->sk);
+	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];
+
+	idx = 0;
+	ASSERT_RTNL();
+	for_each_netdev(net, dev) {
+		struct netdev_queue *dev_queue;
+
+		if (idx < s_idx)
+			goto cont;
+		if (idx > s_idx)
+			s_q_idx = 0;
+		q_idx = 0;
+
+		if (tc_dump_qdisc_root(dev->qdisc, skb, cb, &q_idx, s_q_idx) < 0)
+			goto done;
+
+		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)
+			goto done;
+
+cont:
+		idx++;
+	}
+
+done:
+	cb->args[0] = idx;
+	cb->args[1] = q_idx;
+
+	return skb->len;
+}
+
+
+
+/************************************************
+ *	Traffic classes manipulation.		*
+ ************************************************/
+
+
+
+static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n)
+{
+	struct net *net = sock_net(skb->sk);
+	struct tcmsg *tcm = nlmsg_data(n);
+	struct nlattr *tca[TCA_MAX + 1];
+	struct net_device *dev;
+	struct Qdisc *q = NULL;
+	const struct Qdisc_class_ops *cops;
+	unsigned long cl = 0;
+	unsigned long new_cl;
+	u32 portid;
+	u32 clid;
+	u32 qid;
+	int err;
+
+	if ((n->nlmsg_type != RTM_GETTCLASS) &&
+	    !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
+		return -EPERM;
+
+	err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
+	if (err < 0)
+		return err;
+
+	dev = __dev_get_by_index(net, tcm->tcm_ifindex);
+	if (!dev)
+		return -ENODEV;
+
+	/*
+	   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 */
+
+	portid = tcm->tcm_parent;
+	clid = tcm->tcm_handle;
+	qid = TC_H_MAJ(clid);
+
+	if (portid != TC_H_ROOT) {
+		u32 qid1 = TC_H_MAJ(portid);
+
+		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)
+			qid = dev->qdisc->handle;
+
+		/* Now qid is genuine qdisc handle consistent
+		 * both with parent and child.
+		 *
+		 * TC_H_MAJ(portid) still may be unspecified, complete it now.
+		 */
+		if (portid)
+			portid = TC_H_MAKE(qid, portid);
+	} else {
+		if (qid == 0)
+			qid = dev->qdisc->handle;
+	}
+
+	/* OK. Locate qdisc */
+	q = qdisc_lookup(dev, qid);
+	if (!q)
+		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) {
+		if (portid == TC_H_ROOT)
+			clid = qid;
+	} else
+		clid = TC_H_MAKE(qid, clid);
+
+	if (clid)
+		cl = cops->get(q, clid);
+
+	if (cl == 0) {
+		err = -ENOENT;
+		if (n->nlmsg_type != RTM_NEWTCLASS ||
+		    !(n->nlmsg_flags & NLM_F_CREATE))
+			goto out;
+	} else {
+		switch (n->nlmsg_type) {
+		case RTM_NEWTCLASS:
+			err = -EEXIST;
+			if (n->nlmsg_flags & NLM_F_EXCL)
+				goto out;
+			break;
+		case RTM_DELTCLASS:
+			err = -EOPNOTSUPP;
+			if (cops->delete)
+				err = cops->delete(q, cl);
+			if (err == 0)
+				tclass_notify(net, skb, n, q, cl, RTM_DELTCLASS);
+			goto out;
+		case RTM_GETTCLASS:
+			err = tclass_notify(net, skb, n, q, cl, RTM_NEWTCLASS);
+			goto out;
+		default:
+			err = -EINVAL;
+			goto out;
+		}
+	}
+
+	new_cl = cl;
+	err = -EOPNOTSUPP;
+	if (cops->change)
+		err = cops->change(q, clid, portid, tca, &new_cl);
+	if (err == 0)
+		tclass_notify(net, skb, n, q, new_cl, RTM_NEWTCLASS);
+
+out:
+	if (cl)
+		cops->put(q, cl);
+
+	return err;
+}
+
+
+static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q,
+			  unsigned long cl,
+			  u32 portid, u32 seq, u16 flags, int event)
+{
+	struct tcmsg *tcm;
+	struct nlmsghdr  *nlh;
+	unsigned char *b = skb_tail_pointer(skb);
+	struct gnet_dump d;
+	const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops;
+
+	cond_resched();
+	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
+	if (!nlh)
+		goto out_nlmsg_trim;
+	tcm = nlmsg_data(nlh);
+	tcm->tcm_family = AF_UNSPEC;
+	tcm->tcm__pad1 = 0;
+	tcm->tcm__pad2 = 0;
+	tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
+	tcm->tcm_parent = q->handle;
+	tcm->tcm_handle = q->handle;
+	tcm->tcm_info = 0;
+	if (nla_put_string(skb, TCA_KIND, q->ops->id))
+		goto nla_put_failure;
+	if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0)
+		goto nla_put_failure;
+
+	if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
+					 qdisc_root_sleeping_lock(q), &d) < 0)
+		goto nla_put_failure;
+
+	if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0)
+		goto nla_put_failure;
+
+	if (gnet_stats_finish_copy(&d) < 0)
+		goto nla_put_failure;
+
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
+	return skb->len;
+
+out_nlmsg_trim:
+nla_put_failure:
+	nlmsg_trim(skb, b);
+	return -1;
+}
+
+static int tclass_notify(struct net *net, struct sk_buff *oskb,
+			 struct nlmsghdr *n, struct Qdisc *q,
+			 unsigned long cl, int event)
+{
+	struct sk_buff *skb;
+	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
+
+	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
+	if (!skb)
+		return -ENOBUFS;
+
+	if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, event) < 0) {
+		kfree_skb(skb);
+		return -EINVAL;
+	}
+
+	return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
+			      n->nlmsg_flags & NLM_F_ECHO);
+}
+
+struct qdisc_dump_args {
+	struct qdisc_walker	w;
+	struct sk_buff		*skb;
+	struct netlink_callback	*cb;
+};
+
+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;
+
+	return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).portid,
+			      a->cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTCLASS);
+}
+
+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;
+}
+
+static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	struct tcmsg *tcm = nlmsg_data(cb->nlh);
+	struct net *net = sock_net(skb->sk);
+	struct netdev_queue *dev_queue;
+	struct net_device *dev;
+	int t, s_t;
+
+	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
+		return 0;
+	dev = dev_get_by_index(net, tcm->tcm_ifindex);
+	if (!dev)
+		return 0;
+
+	s_t = cb->args[0];
+	t = 0;
+
+	if (tc_dump_tclass_root(dev->qdisc, skb, tcm, cb, &t, s_t) < 0)
+		goto done;
+
+	dev_queue = dev_ingress_queue(dev);
+	if (dev_queue &&
+	    tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb,
+				&t, s_t) < 0)
+		goto done;
+
+done:
+	cb->args[0] = t;
+
+	dev_put(dev);
+	return skb->len;
+}
+
+/* Main classifier routine: scans classifier chain attached
+ * to this qdisc, (optionally) tests for protocol and asks
+ * specific classifiers.
+ */
+int tc_classify_compat(struct sk_buff *skb, const struct tcf_proto *tp,
+		       struct tcf_result *res)
+{
+	__be16 protocol = tc_skb_protocol(skb);
+	int err;
+
+	for (; tp; tp = rcu_dereference_bh(tp->next)) {
+		if (tp->protocol != protocol &&
+		    tp->protocol != htons(ETH_P_ALL))
+			continue;
+		err = tp->classify(skb, tp, res);
+
+		if (err >= 0) {
+#ifdef CONFIG_NET_CLS_ACT
+			if (err != TC_ACT_RECLASSIFY && skb->tc_verd)
+				skb->tc_verd = SET_TC_VERD(skb->tc_verd, 0);
+#endif
+			return err;
+		}
+	}
+	return -1;
+}
+EXPORT_SYMBOL(tc_classify_compat);
+
+int tc_classify(struct sk_buff *skb, const struct tcf_proto *tp,
+		struct tcf_result *res)
+{
+	int err = 0;
+#ifdef CONFIG_NET_CLS_ACT
+	const struct tcf_proto *otp = tp;
+reclassify:
+#endif
+
+	err = tc_classify_compat(skb, tp, res);
+#ifdef CONFIG_NET_CLS_ACT
+	if (err == TC_ACT_RECLASSIFY) {
+		u32 verd = G_TC_VERD(skb->tc_verd);
+		tp = otp;
+
+		if (verd++ >= MAX_REC_LOOP) {
+			net_notice_ratelimited("%s: packet reclassify loop rule prio %u protocol %02x\n",
+					       tp->q->ops->id,
+					       tp->prio & 0xffff,
+					       ntohs(tp->protocol));
+			return TC_ACT_SHOT;
+		}
+		skb->tc_verd = SET_TC_VERD(skb->tc_verd, verd);
+		goto reclassify;
+	}
+#endif
+	return err;
+}
+EXPORT_SYMBOL(tc_classify);
+
+bool tcf_destroy(struct tcf_proto *tp, bool force)
+{
+	if (tp->ops->destroy(tp, force)) {
+		module_put(tp->ops->owner);
+		kfree_rcu(tp, rcu);
+		return true;
+	}
+
+	return false;
+}
+
+void tcf_destroy_chain(struct tcf_proto __rcu **fl)
+{
+	struct tcf_proto *tp;
+
+	while ((tp = rtnl_dereference(*fl)) != NULL) {
+		RCU_INIT_POINTER(*fl, tp->next);
+		tcf_destroy(tp, true);
+	}
+}
+EXPORT_SYMBOL(tcf_destroy_chain);
+
+#ifdef CONFIG_PROC_FS
+static int psched_show(struct seq_file *seq, void *v)
+{
+	struct timespec ts;
+
+	hrtimer_get_res(CLOCK_MONOTONIC, &ts);
+	seq_printf(seq, "%08x %08x %08x %08x\n",
+		   (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1),
+		   1000000,
+		   (u32)NSEC_PER_SEC/(u32)ktime_to_ns(timespec_to_ktime(ts)));
+
+	return 0;
+}
+
+static int psched_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, psched_show, NULL);
+}
+
+static const struct file_operations psched_fops = {
+	.owner = THIS_MODULE,
+	.open = psched_open,
+	.read  = seq_read,
+	.llseek = seq_lseek,
+	.release = single_release,
+};
+
+static int __net_init psched_net_init(struct net *net)
+{
+	struct proc_dir_entry *e;
+
+	e = proc_create("psched", 0, net->proc_net, &psched_fops);
+	if (e == NULL)
+		return -ENOMEM;
+
+	return 0;
+}
+
+static void __net_exit psched_net_exit(struct net *net)
+{
+	remove_proc_entry("psched", net->proc_net);
+}
+#else
+static int __net_init psched_net_init(struct net *net)
+{
+	return 0;
+}
+
+static void __net_exit psched_net_exit(struct net *net)
+{
+}
+#endif
+
+static struct pernet_operations psched_net_ops = {
+	.init = psched_net_init,
+	.exit = psched_net_exit,
+};
+
+static int __init pktsched_init(void)
+{
+	int err;
+
+	err = register_pernet_subsys(&psched_net_ops);
+	if (err) {
+		pr_err("pktsched_init: "
+		       "cannot initialize per netns operations\n");
+		return err;
+	}
+
+	register_qdisc(&pfifo_fast_ops);
+	register_qdisc(&pfifo_qdisc_ops);
+	register_qdisc(&bfifo_qdisc_ops);
+	register_qdisc(&pfifo_head_drop_qdisc_ops);
+	register_qdisc(&mq_qdisc_ops);
+
+	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);
+
+	return 0;
+}
+
+subsys_initcall(pktsched_init);