--- /dev/null
+/*
+ * 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);
Code Review / kvmfornfv.git / blobdiff