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-rw-r--r--net/sched/sch_api.c2392
1 files changed, 2392 insertions, 0 deletions
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
new file mode 100644
index 000000000..e9eaf6372
--- /dev/null
+++ b/net/sched/sch_api.c
@@ -0,0 +1,2392 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * net/sched/sch_api.c Packet scheduler API.
+ *
+ * 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/slab.h>
+#include <linux/hashtable.h>
+
+#include <net/net_namespace.h>
+#include <net/sock.h>
+#include <net/netlink.h>
+#include <net/pkt_sched.h>
+#include <net/pkt_cls.h>
+#include <net/tc_wrapper.h>
+
+#include <trace/events/qdisc.h>
+
+/*
+
+ Short review.
+ -------------
+
+ This file consists of two interrelated parts:
+
+ 1. queueing disciplines manager frontend.
+ 2. traffic classes manager frontend.
+
+ Generally, queueing discipline ("qdisc") is a black box,
+ which is able to enqueue packets and to dequeue them (when
+ device is ready to send something) in order and at times
+ determined by algorithm hidden in it.
+
+ qdisc's are divided to two categories:
+ - "queues", which have no internal structure visible from outside.
+ - "schedulers", which split all the packets to "traffic classes",
+ using "packet classifiers" (look at cls_api.c)
+
+ In turn, classes may have child qdiscs (as rule, queues)
+ attached to them etc. etc. etc.
+
+ The goal of the routines in this file is to translate
+ information supplied by user in the form of handles
+ to more intelligible for kernel form, to make some sanity
+ checks and part of work, which is common to all qdiscs
+ and to provide rtnetlink notifications.
+
+ All real intelligent work is done inside qdisc modules.
+
+
+
+ Every discipline has two major routines: enqueue and dequeue.
+
+ ---dequeue
+
+ dequeue usually returns a skb to send. It is allowed to return NULL,
+ but it does not mean that queue is empty, it just means that
+ discipline does not want to send anything this time.
+ Queue is really empty if q->q.qlen == 0.
+ For complicated disciplines with multiple queues q->q is not
+ real packet queue, but however q->q.qlen must be valid.
+
+ ---enqueue
+
+ enqueue returns 0, if packet was enqueued successfully.
+ If packet (this one or another one) was dropped, it returns
+ not zero error code.
+ NET_XMIT_DROP - this packet dropped
+ Expected action: do not backoff, but wait until queue will clear.
+ NET_XMIT_CN - probably this packet enqueued, but another one dropped.
+ Expected action: backoff or ignore
+
+ Auxiliary routines:
+
+ ---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->find && cops->walk && cops->leaf))
+ goto out_einval;
+
+ if (cops->tcf_block && !(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);
+
+void 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);
+
+ WARN(err, "unregister qdisc(%s) failed\n", qops->id);
+}
+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);
+ strscpy(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;
+}
+
+#ifdef CONFIG_NET_SCH_DEFAULT
+/* Set default value from kernel config */
+static int __init sch_default_qdisc(void)
+{
+ return qdisc_set_default(CONFIG_DEFAULT_NET_SCH);
+}
+late_initcall(sch_default_qdisc);
+#endif
+
+/* We know handle. Find qdisc among all qdisc's attached to device
+ * (root qdisc, all its children, children of children etc.)
+ * Note: caller either uses rtnl or rcu_read_lock()
+ */
+
+static struct Qdisc *qdisc_match_from_root(struct Qdisc *root, u32 handle)
+{
+ struct Qdisc *q;
+
+ if (!qdisc_dev(root))
+ return (root->handle == handle ? root : NULL);
+
+ if (!(root->flags & TCQ_F_BUILTIN) &&
+ root->handle == handle)
+ return root;
+
+ hash_for_each_possible_rcu(qdisc_dev(root)->qdisc_hash, q, hash, handle,
+ lockdep_rtnl_is_held()) {
+ if (q->handle == handle)
+ return q;
+ }
+ return NULL;
+}
+
+void qdisc_hash_add(struct Qdisc *q, bool invisible)
+{
+ if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) {
+ ASSERT_RTNL();
+ hash_add_rcu(qdisc_dev(q)->qdisc_hash, &q->hash, q->handle);
+ if (invisible)
+ q->flags |= TCQ_F_INVISIBLE;
+ }
+}
+EXPORT_SYMBOL(qdisc_hash_add);
+
+void qdisc_hash_del(struct Qdisc *q)
+{
+ if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) {
+ ASSERT_RTNL();
+ hash_del_rcu(&q->hash);
+ }
+}
+EXPORT_SYMBOL(qdisc_hash_del);
+
+struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle)
+{
+ struct Qdisc *q;
+
+ if (!handle)
+ return NULL;
+ q = qdisc_match_from_root(rtnl_dereference(dev->qdisc), handle);
+ if (q)
+ goto out;
+
+ if (dev_ingress_queue(dev))
+ q = qdisc_match_from_root(
+ rtnl_dereference(dev_ingress_queue(dev)->qdisc_sleeping),
+ handle);
+out:
+ return q;
+}
+
+struct Qdisc *qdisc_lookup_rcu(struct net_device *dev, u32 handle)
+{
+ struct netdev_queue *nq;
+ struct Qdisc *q;
+
+ if (!handle)
+ return NULL;
+ q = qdisc_match_from_root(rcu_dereference(dev->qdisc), handle);
+ if (q)
+ goto out;
+
+ nq = dev_ingress_queue_rcu(dev);
+ if (nq)
+ q = qdisc_match_from_root(rcu_dereference(nq->qdisc_sleeping),
+ handle);
+out:
+ return q;
+}
+
+static struct Qdisc *qdisc_leaf(struct Qdisc *p, u32 classid)
+{
+ unsigned long cl;
+ const struct Qdisc_class_ops *cops = p->ops->cl_ops;
+
+ if (cops == NULL)
+ return NULL;
+ cl = cops->find(p, classid);
+
+ if (cl == 0)
+ return NULL;
+ return cops->leaf(p, cl);
+}
+
+/* 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 netlink_ext_ack *extack)
+{
+ struct qdisc_rate_table *rtab;
+
+ if (tab == NULL || r->rate == 0 ||
+ r->cell_log == 0 || r->cell_log >= 32 ||
+ nla_len(tab) != TC_RTAB_SIZE) {
+ NL_SET_ERR_MSG(extack, "Invalid rate table parameters for searching");
+ 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;
+ } else {
+ NL_SET_ERR_MSG(extack, "Failed to allocate new qdisc rate table");
+ }
+ 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 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 netlink_ext_ack *extack)
+{
+ 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_deprecated(tb, TCA_STAB_MAX, opt, stab_policy,
+ extack);
+ if (err < 0)
+ return ERR_PTR(err);
+ if (!tb[TCA_STAB_BASE]) {
+ NL_SET_ERR_MSG(extack, "Size table base attribute is missing");
+ return ERR_PTR(-EINVAL);
+ }
+
+ s = nla_data(tb[TCA_STAB_BASE]);
+
+ if (s->tsize > 0) {
+ if (!tb[TCA_STAB_DATA]) {
+ NL_SET_ERR_MSG(extack, "Size table data attribute is missing");
+ 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)) {
+ NL_SET_ERR_MSG(extack, "Invalid size of size table");
+ return ERR_PTR(-EINVAL);
+ }
+
+ list_for_each_entry(stab, &qdisc_stab_list, list) {
+ if (memcmp(&stab->szopts, s, sizeof(*s)))
+ continue;
+ if (tsize > 0 &&
+ memcmp(stab->data, tab, flex_array_size(stab, data, tsize)))
+ continue;
+ stab->refcnt++;
+ return stab;
+ }
+
+ if (s->size_log > STAB_SIZE_LOG_MAX ||
+ s->cell_log > STAB_SIZE_LOG_MAX) {
+ NL_SET_ERR_MSG(extack, "Invalid logarithmic size of size table");
+ return ERR_PTR(-EINVAL);
+ }
+
+ stab = kmalloc(struct_size(stab, data, tsize), GFP_KERNEL);
+ if (!stab)
+ return ERR_PTR(-ENOMEM);
+
+ stab->refcnt = 1;
+ stab->szopts = *s;
+ if (tsize > 0)
+ memcpy(stab->data, tab, flex_array_size(stab, data, tsize));
+
+ list_add_tail(&stab->list, &qdisc_stab_list);
+
+ return stab;
+}
+
+void qdisc_put_stab(struct qdisc_size_table *tab)
+{
+ if (!tab)
+ return;
+
+ if (--tab->refcnt == 0) {
+ list_del(&tab->list);
+ kfree_rcu(tab, rcu);
+ }
+}
+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_noflag(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();
+ __netif_schedule(qdisc_root(wd->qdisc));
+ rcu_read_unlock();
+
+ return HRTIMER_NORESTART;
+}
+
+void qdisc_watchdog_init_clockid(struct qdisc_watchdog *wd, struct Qdisc *qdisc,
+ clockid_t clockid)
+{
+ hrtimer_init(&wd->timer, clockid, HRTIMER_MODE_ABS_PINNED);
+ wd->timer.function = qdisc_watchdog;
+ wd->qdisc = qdisc;
+}
+EXPORT_SYMBOL(qdisc_watchdog_init_clockid);
+
+void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc)
+{
+ qdisc_watchdog_init_clockid(wd, qdisc, CLOCK_MONOTONIC);
+}
+EXPORT_SYMBOL(qdisc_watchdog_init);
+
+void qdisc_watchdog_schedule_range_ns(struct qdisc_watchdog *wd, u64 expires,
+ u64 delta_ns)
+{
+ bool deactivated;
+
+ rcu_read_lock();
+ deactivated = test_bit(__QDISC_STATE_DEACTIVATED,
+ &qdisc_root_sleeping(wd->qdisc)->state);
+ rcu_read_unlock();
+ if (deactivated)
+ return;
+
+ if (hrtimer_is_queued(&wd->timer)) {
+ u64 softexpires;
+
+ softexpires = ktime_to_ns(hrtimer_get_softexpires(&wd->timer));
+ /* If timer is already set in [expires, expires + delta_ns],
+ * do not reprogram it.
+ */
+ if (softexpires - expires <= delta_ns)
+ return;
+ }
+
+ hrtimer_start_range_ns(&wd->timer,
+ ns_to_ktime(expires),
+ delta_ns,
+ HRTIMER_MODE_ABS_PINNED);
+}
+EXPORT_SYMBOL(qdisc_watchdog_schedule_range_ns);
+
+void qdisc_watchdog_cancel(struct qdisc_watchdog *wd)
+{
+ hrtimer_cancel(&wd->timer);
+}
+EXPORT_SYMBOL(qdisc_watchdog_cancel);
+
+static struct hlist_head *qdisc_class_hash_alloc(unsigned int n)
+{
+ struct hlist_head *h;
+ unsigned int i;
+
+ h = kvmalloc_array(n, sizeof(struct hlist_head), GFP_KERNEL);
+
+ if (h != NULL) {
+ for (i = 0; i < n; i++)
+ INIT_HLIST_HEAD(&h[i]);
+ }
+ return h;
+}
+
+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);
+
+ kvfree(ohash);
+}
+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)
+ 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)
+{
+ kvfree(clhash->hash);
+}
+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_reduce_backlog(struct Qdisc *sch, int n, int len)
+{
+ bool qdisc_is_offloaded = sch->flags & TCQ_F_OFFLOADED;
+ const struct Qdisc_class_ops *cops;
+ unsigned long cl;
+ u32 parentid;
+ bool notify;
+ int drops;
+
+ if (n == 0 && len == 0)
+ return;
+ drops = max_t(int, n, 0);
+ rcu_read_lock();
+ while ((parentid = sch->parent)) {
+ if (TC_H_MAJ(parentid) == TC_H_MAJ(TC_H_INGRESS))
+ break;
+
+ if (sch->flags & TCQ_F_NOPARENT)
+ break;
+ /* Notify parent qdisc only if child qdisc becomes empty.
+ *
+ * If child was empty even before update then backlog
+ * counter is screwed and we skip notification because
+ * parent class is already passive.
+ *
+ * If the original child was offloaded then it is allowed
+ * to be seem as empty, so the parent is notified anyway.
+ */
+ notify = !sch->q.qlen && !WARN_ON_ONCE(!n &&
+ !qdisc_is_offloaded);
+ /* TODO: perform the search on a per txq basis */
+ sch = qdisc_lookup(qdisc_dev(sch), TC_H_MAJ(parentid));
+ if (sch == NULL) {
+ WARN_ON_ONCE(parentid != TC_H_ROOT);
+ break;
+ }
+ cops = sch->ops->cl_ops;
+ if (notify && cops->qlen_notify) {
+ cl = cops->find(sch, parentid);
+ cops->qlen_notify(sch, cl);
+ }
+ sch->q.qlen -= n;
+ sch->qstats.backlog -= len;
+ __qdisc_qstats_drop(sch, drops);
+ }
+ rcu_read_unlock();
+}
+EXPORT_SYMBOL(qdisc_tree_reduce_backlog);
+
+int qdisc_offload_dump_helper(struct Qdisc *sch, enum tc_setup_type type,
+ void *type_data)
+{
+ struct net_device *dev = qdisc_dev(sch);
+ int err;
+
+ sch->flags &= ~TCQ_F_OFFLOADED;
+ if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
+ return 0;
+
+ err = dev->netdev_ops->ndo_setup_tc(dev, type, type_data);
+ if (err == -EOPNOTSUPP)
+ return 0;
+
+ if (!err)
+ sch->flags |= TCQ_F_OFFLOADED;
+
+ return err;
+}
+EXPORT_SYMBOL(qdisc_offload_dump_helper);
+
+void qdisc_offload_graft_helper(struct net_device *dev, struct Qdisc *sch,
+ struct Qdisc *new, struct Qdisc *old,
+ enum tc_setup_type type, void *type_data,
+ struct netlink_ext_ack *extack)
+{
+ bool any_qdisc_is_offloaded;
+ int err;
+
+ if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
+ return;
+
+ err = dev->netdev_ops->ndo_setup_tc(dev, type, type_data);
+
+ /* Don't report error if the graft is part of destroy operation. */
+ if (!err || !new || new == &noop_qdisc)
+ return;
+
+ /* Don't report error if the parent, the old child and the new
+ * one are not offloaded.
+ */
+ any_qdisc_is_offloaded = new->flags & TCQ_F_OFFLOADED;
+ any_qdisc_is_offloaded |= sch && sch->flags & TCQ_F_OFFLOADED;
+ any_qdisc_is_offloaded |= old && old->flags & TCQ_F_OFFLOADED;
+
+ if (any_qdisc_is_offloaded)
+ NL_SET_ERR_MSG(extack, "Offloading graft operation failed.");
+}
+EXPORT_SYMBOL(qdisc_offload_graft_helper);
+
+void qdisc_offload_query_caps(struct net_device *dev,
+ enum tc_setup_type type,
+ void *caps, size_t caps_len)
+{
+ const struct net_device_ops *ops = dev->netdev_ops;
+ struct tc_query_caps_base base = {
+ .type = type,
+ .caps = caps,
+ };
+
+ memset(caps, 0, caps_len);
+
+ if (ops->ndo_setup_tc)
+ ops->ndo_setup_tc(dev, TC_QUERY_CAPS, &base);
+}
+EXPORT_SYMBOL(qdisc_offload_query_caps);
+
+static void qdisc_offload_graft_root(struct net_device *dev,
+ struct Qdisc *new, struct Qdisc *old,
+ struct netlink_ext_ack *extack)
+{
+ struct tc_root_qopt_offload graft_offload = {
+ .command = TC_ROOT_GRAFT,
+ .handle = new ? new->handle : 0,
+ .ingress = (new && new->flags & TCQ_F_INGRESS) ||
+ (old && old->flags & TCQ_F_INGRESS),
+ };
+
+ qdisc_offload_graft_helper(dev, NULL, new, old,
+ TC_SETUP_ROOT_QDISC, &graft_offload, extack);
+}
+
+static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid,
+ u32 portid, u32 seq, u16 flags, int event,
+ struct netlink_ext_ack *extack)
+{
+ struct gnet_stats_basic_sync __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 block_index;
+ __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 = refcount_read(&q->refcnt);
+ if (nla_put_string(skb, TCA_KIND, q->ops->id))
+ goto nla_put_failure;
+ if (q->ops->ingress_block_get) {
+ block_index = q->ops->ingress_block_get(q);
+ if (block_index &&
+ nla_put_u32(skb, TCA_INGRESS_BLOCK, block_index))
+ goto nla_put_failure;
+ }
+ if (q->ops->egress_block_get) {
+ block_index = q->ops->egress_block_get(q);
+ if (block_index &&
+ nla_put_u32(skb, TCA_EGRESS_BLOCK, block_index))
+ goto nla_put_failure;
+ }
+ if (q->ops->dump && q->ops->dump(q, skb) < 0)
+ goto nla_put_failure;
+ if (nla_put_u8(skb, TCA_HW_OFFLOAD, !!(q->flags & TCQ_F_OFFLOADED)))
+ goto nla_put_failure;
+ qlen = qdisc_qlen_sum(q);
+
+ 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,
+ NULL, &d, TCA_PAD) < 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, true) < 0 ||
+ gnet_stats_copy_rate_est(&d, &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;
+
+ if (extack && extack->_msg &&
+ nla_put_string(skb, TCA_EXT_WARN_MSG, extack->_msg))
+ goto out_nlmsg_trim;
+
+ 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, bool dump_invisible)
+{
+ if (q->flags & TCQ_F_BUILTIN)
+ return true;
+ if ((q->flags & TCQ_F_INVISIBLE) && !dump_invisible)
+ return true;
+
+ return false;
+}
+
+static int qdisc_notify(struct net *net, struct sk_buff *oskb,
+ struct nlmsghdr *n, u32 clid,
+ struct Qdisc *old, struct Qdisc *new,
+ struct netlink_ext_ack *extack)
+{
+ 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, false)) {
+ if (tc_fill_qdisc(skb, old, clid, portid, n->nlmsg_seq,
+ 0, RTM_DELQDISC, extack) < 0)
+ goto err_out;
+ }
+ if (new && !tc_qdisc_dump_ignore(new, false)) {
+ if (tc_fill_qdisc(skb, new, clid, portid, n->nlmsg_seq,
+ old ? NLM_F_REPLACE : 0, RTM_NEWQDISC, extack) < 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 void notify_and_destroy(struct net *net, struct sk_buff *skb,
+ struct nlmsghdr *n, u32 clid,
+ struct Qdisc *old, struct Qdisc *new,
+ struct netlink_ext_ack *extack)
+{
+ if (new || old)
+ qdisc_notify(net, skb, n, clid, old, new, extack);
+
+ if (old)
+ qdisc_put(old);
+}
+
+static void qdisc_clear_nolock(struct Qdisc *sch)
+{
+ sch->flags &= ~TCQ_F_NOLOCK;
+ if (!(sch->flags & TCQ_F_CPUSTATS))
+ return;
+
+ free_percpu(sch->cpu_bstats);
+ free_percpu(sch->cpu_qstats);
+ sch->cpu_bstats = NULL;
+ sch->cpu_qstats = NULL;
+ sch->flags &= ~TCQ_F_CPUSTATS;
+}
+
+/* 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 netlink_ext_ack *extack)
+{
+ struct Qdisc *q = old;
+ struct net *net = dev_net(dev);
+
+ if (parent == NULL) {
+ unsigned int i, num_q, ingress;
+ struct netdev_queue *dev_queue;
+
+ ingress = 0;
+ num_q = dev->num_tx_queues;
+ if ((q && q->flags & TCQ_F_INGRESS) ||
+ (new && new->flags & TCQ_F_INGRESS)) {
+ ingress = 1;
+ dev_queue = dev_ingress_queue(dev);
+ if (!dev_queue) {
+ NL_SET_ERR_MSG(extack, "Device does not have an ingress queue");
+ return -ENOENT;
+ }
+
+ q = rtnl_dereference(dev_queue->qdisc_sleeping);
+
+ /* This is the counterpart of that qdisc_refcount_inc_nz() call in
+ * __tcf_qdisc_find() for filter requests.
+ */
+ if (!qdisc_refcount_dec_if_one(q)) {
+ NL_SET_ERR_MSG(extack,
+ "Current ingress or clsact Qdisc has ongoing filter requests");
+ return -EBUSY;
+ }
+ }
+
+ if (dev->flags & IFF_UP)
+ dev_deactivate(dev);
+
+ qdisc_offload_graft_root(dev, new, old, extack);
+
+ if (new && new->ops->attach && !ingress)
+ goto skip;
+
+ if (!ingress) {
+ for (i = 0; i < num_q; i++) {
+ dev_queue = netdev_get_tx_queue(dev, i);
+ old = dev_graft_qdisc(dev_queue, new);
+
+ if (new && i > 0)
+ qdisc_refcount_inc(new);
+ qdisc_put(old);
+ }
+ } else {
+ old = dev_graft_qdisc(dev_queue, NULL);
+
+ /* {ingress,clsact}_destroy() @old before grafting @new to avoid
+ * unprotected concurrent accesses to net_device::miniq_{in,e}gress
+ * pointer(s) in mini_qdisc_pair_swap().
+ */
+ qdisc_notify(net, skb, n, classid, old, new, extack);
+ qdisc_destroy(old);
+
+ dev_graft_qdisc(dev_queue, new);
+ }
+
+skip:
+ if (!ingress) {
+ old = rtnl_dereference(dev->qdisc);
+ if (new && !new->ops->attach)
+ qdisc_refcount_inc(new);
+ rcu_assign_pointer(dev->qdisc, new ? : &noop_qdisc);
+
+ notify_and_destroy(net, skb, n, classid, old, new, extack);
+
+ if (new && new->ops->attach)
+ new->ops->attach(new);
+ }
+
+ if (dev->flags & IFF_UP)
+ dev_activate(dev);
+ } else {
+ const struct Qdisc_class_ops *cops = parent->ops->cl_ops;
+ unsigned long cl;
+ int err;
+
+ /* Only support running class lockless if parent is lockless */
+ if (new && (new->flags & TCQ_F_NOLOCK) && !(parent->flags & TCQ_F_NOLOCK))
+ qdisc_clear_nolock(new);
+
+ if (!cops || !cops->graft)
+ return -EOPNOTSUPP;
+
+ cl = cops->find(parent, classid);
+ if (!cl) {
+ NL_SET_ERR_MSG(extack, "Specified class not found");
+ return -ENOENT;
+ }
+
+ if (new && new->ops == &noqueue_qdisc_ops) {
+ NL_SET_ERR_MSG(extack, "Cannot assign noqueue to a class");
+ return -EINVAL;
+ }
+
+ err = cops->graft(parent, cl, new, &old, extack);
+ if (err)
+ return err;
+ notify_and_destroy(net, skb, n, classid, old, new, extack);
+ }
+ return 0;
+}
+
+static int qdisc_block_indexes_set(struct Qdisc *sch, struct nlattr **tca,
+ struct netlink_ext_ack *extack)
+{
+ u32 block_index;
+
+ if (tca[TCA_INGRESS_BLOCK]) {
+ block_index = nla_get_u32(tca[TCA_INGRESS_BLOCK]);
+
+ if (!block_index) {
+ NL_SET_ERR_MSG(extack, "Ingress block index cannot be 0");
+ return -EINVAL;
+ }
+ if (!sch->ops->ingress_block_set) {
+ NL_SET_ERR_MSG(extack, "Ingress block sharing is not supported");
+ return -EOPNOTSUPP;
+ }
+ sch->ops->ingress_block_set(sch, block_index);
+ }
+ if (tca[TCA_EGRESS_BLOCK]) {
+ block_index = nla_get_u32(tca[TCA_EGRESS_BLOCK]);
+
+ if (!block_index) {
+ NL_SET_ERR_MSG(extack, "Egress block index cannot be 0");
+ return -EINVAL;
+ }
+ if (!sch->ops->egress_block_set) {
+ NL_SET_ERR_MSG(extack, "Egress block sharing is not supported");
+ return -EOPNOTSUPP;
+ }
+ sch->ops->egress_block_set(sch, block_index);
+ }
+ return 0;
+}
+
+/*
+ Allocate and initialize new qdisc.
+
+ Parameters are passed via opt.
+ */
+
+static struct Qdisc *qdisc_create(struct net_device *dev,
+ struct netdev_queue *dev_queue,
+ u32 parent, u32 handle,
+ struct nlattr **tca, int *errp,
+ struct netlink_ext_ack *extack)
+{
+ 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_strscpy(name, kind, IFNAMSIZ) >= 0) {
+ /* 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) {
+ NL_SET_ERR_MSG(extack, "Specified qdisc kind is unknown");
+ goto err_out;
+ }
+
+ sch = qdisc_alloc(dev_queue, ops, extack);
+ if (IS_ERR(sch)) {
+ err = PTR_ERR(sch);
+ goto err_out2;
+ }
+
+ sch->parent = parent;
+
+ if (handle == TC_H_INGRESS) {
+ if (!(sch->flags & TCQ_F_INGRESS)) {
+ NL_SET_ERR_MSG(extack,
+ "Specified parent ID is reserved for ingress and clsact Qdiscs");
+ err = -EINVAL;
+ goto err_out3;
+ }
+ handle = TC_H_MAKE(TC_H_INGRESS, 0);
+ } else {
+ if (handle == 0) {
+ handle = qdisc_alloc_handle(dev);
+ if (handle == 0) {
+ NL_SET_ERR_MSG(extack, "Maximum number of qdisc handles was exceeded");
+ err = -ENOSPC;
+ goto err_out3;
+ }
+ }
+ if (!netif_is_multiqueue(dev))
+ sch->flags |= TCQ_F_ONETXQUEUE;
+ }
+
+ sch->handle = handle;
+
+ /* This exist to keep backward compatible with a userspace
+ * loophole, what allowed userspace to get IFF_NO_QUEUE
+ * facility on older kernels by setting tx_queue_len=0 (prior
+ * to qdisc init), and then forgot to reinit tx_queue_len
+ * before again attaching a qdisc.
+ */
+ if ((dev->priv_flags & IFF_NO_QUEUE) && (dev->tx_queue_len == 0)) {
+ dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
+ netdev_info(dev, "Caught tx_queue_len zero misconfig\n");
+ }
+
+ err = qdisc_block_indexes_set(sch, tca, extack);
+ if (err)
+ goto err_out3;
+
+ if (tca[TCA_STAB]) {
+ stab = qdisc_get_stab(tca[TCA_STAB], extack);
+ if (IS_ERR(stab)) {
+ err = PTR_ERR(stab);
+ goto err_out3;
+ }
+ rcu_assign_pointer(sch->stab, stab);
+ }
+
+ if (ops->init) {
+ err = ops->init(sch, tca[TCA_OPTIONS], extack);
+ if (err != 0)
+ goto err_out4;
+ }
+
+ if (tca[TCA_RATE]) {
+ err = -EOPNOTSUPP;
+ if (sch->flags & TCQ_F_MQROOT) {
+ NL_SET_ERR_MSG(extack, "Cannot attach rate estimator to a multi-queue root qdisc");
+ goto err_out4;
+ }
+
+ err = gen_new_estimator(&sch->bstats,
+ sch->cpu_bstats,
+ &sch->rate_est,
+ NULL,
+ true,
+ tca[TCA_RATE]);
+ if (err) {
+ NL_SET_ERR_MSG(extack, "Failed to generate new estimator");
+ goto err_out4;
+ }
+ }
+
+ qdisc_hash_add(sch, false);
+ trace_qdisc_create(ops, dev, parent);
+
+ return sch;
+
+err_out4:
+ /* Even if ops->init() failed, we call ops->destroy()
+ * like qdisc_create_dflt().
+ */
+ if (ops->destroy)
+ ops->destroy(sch);
+ qdisc_put_stab(rtnl_dereference(sch->stab));
+err_out3:
+ netdev_put(dev, &sch->dev_tracker);
+ qdisc_free(sch);
+err_out2:
+ module_put(ops->owner);
+err_out:
+ *errp = err;
+ return NULL;
+}
+
+static int qdisc_change(struct Qdisc *sch, struct nlattr **tca,
+ struct netlink_ext_ack *extack)
+{
+ struct qdisc_size_table *ostab, *stab = NULL;
+ int err = 0;
+
+ if (tca[TCA_OPTIONS]) {
+ if (!sch->ops->change) {
+ NL_SET_ERR_MSG(extack, "Change operation not supported by specified qdisc");
+ return -EINVAL;
+ }
+ if (tca[TCA_INGRESS_BLOCK] || tca[TCA_EGRESS_BLOCK]) {
+ NL_SET_ERR_MSG(extack, "Change of blocks is not supported");
+ return -EOPNOTSUPP;
+ }
+ err = sch->ops->change(sch, tca[TCA_OPTIONS], extack);
+ if (err)
+ return err;
+ }
+
+ if (tca[TCA_STAB]) {
+ stab = qdisc_get_stab(tca[TCA_STAB], extack);
+ 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,
+ NULL,
+ true,
+ 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;
+}
+
+const struct nla_policy rtm_tca_policy[TCA_MAX + 1] = {
+ [TCA_KIND] = { .type = NLA_STRING },
+ [TCA_RATE] = { .type = NLA_BINARY,
+ .len = sizeof(struct tc_estimator) },
+ [TCA_STAB] = { .type = NLA_NESTED },
+ [TCA_DUMP_INVISIBLE] = { .type = NLA_FLAG },
+ [TCA_CHAIN] = { .type = NLA_U32 },
+ [TCA_INGRESS_BLOCK] = { .type = NLA_U32 },
+ [TCA_EGRESS_BLOCK] = { .type = NLA_U32 },
+};
+
+/*
+ * Delete/get qdisc.
+ */
+
+static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n,
+ struct netlink_ext_ack *extack)
+{
+ 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;
+
+ err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX,
+ rtm_tca_policy, extack);
+ 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) {
+ NL_SET_ERR_MSG(extack, "Failed to find qdisc with specified classid");
+ return -ENOENT;
+ }
+ q = qdisc_leaf(p, clid);
+ } else if (dev_ingress_queue(dev)) {
+ q = rtnl_dereference(dev_ingress_queue(dev)->qdisc_sleeping);
+ }
+ } else {
+ q = rtnl_dereference(dev->qdisc);
+ }
+ if (!q) {
+ NL_SET_ERR_MSG(extack, "Cannot find specified qdisc on specified device");
+ return -ENOENT;
+ }
+
+ if (tcm->tcm_handle && q->handle != tcm->tcm_handle) {
+ NL_SET_ERR_MSG(extack, "Invalid handle");
+ return -EINVAL;
+ }
+ } else {
+ q = qdisc_lookup(dev, tcm->tcm_handle);
+ if (!q) {
+ NL_SET_ERR_MSG(extack, "Failed to find qdisc with specified handle");
+ return -ENOENT;
+ }
+ }
+
+ if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) {
+ NL_SET_ERR_MSG(extack, "Invalid qdisc name");
+ return -EINVAL;
+ }
+
+ if (n->nlmsg_type == RTM_DELQDISC) {
+ if (!clid) {
+ NL_SET_ERR_MSG(extack, "Classid cannot be zero");
+ return -EINVAL;
+ }
+ if (q->handle == 0) {
+ NL_SET_ERR_MSG(extack, "Cannot delete qdisc with handle of zero");
+ return -ENOENT;
+ }
+ err = qdisc_graft(dev, p, skb, n, clid, NULL, q, extack);
+ if (err != 0)
+ return err;
+ } else {
+ qdisc_notify(net, skb, n, clid, NULL, q, NULL);
+ }
+ return 0;
+}
+
+static bool req_create_or_replace(struct nlmsghdr *n)
+{
+ return (n->nlmsg_flags & NLM_F_CREATE &&
+ n->nlmsg_flags & NLM_F_REPLACE);
+}
+
+static bool req_create_exclusive(struct nlmsghdr *n)
+{
+ return (n->nlmsg_flags & NLM_F_CREATE &&
+ n->nlmsg_flags & NLM_F_EXCL);
+}
+
+static bool req_change(struct nlmsghdr *n)
+{
+ return (!(n->nlmsg_flags & NLM_F_CREATE) &&
+ !(n->nlmsg_flags & NLM_F_REPLACE) &&
+ !(n->nlmsg_flags & NLM_F_EXCL));
+}
+
+/*
+ * Create/change qdisc.
+ */
+static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n,
+ struct netlink_ext_ack *extack)
+{
+ 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;
+
+replay:
+ /* Reinit, just in case something touches this. */
+ err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX,
+ rtm_tca_policy, extack);
+ 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) {
+ NL_SET_ERR_MSG(extack, "Failed to find specified qdisc");
+ return -ENOENT;
+ }
+ q = qdisc_leaf(p, clid);
+ } else if (dev_ingress_queue_create(dev)) {
+ q = rtnl_dereference(dev_ingress_queue(dev)->qdisc_sleeping);
+ }
+ } else {
+ q = rtnl_dereference(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)) {
+ NL_SET_ERR_MSG(extack, "NLM_F_REPLACE needed to override");
+ return -EEXIST;
+ }
+ if (TC_H_MIN(tcm->tcm_handle)) {
+ NL_SET_ERR_MSG(extack, "Invalid minor handle");
+ return -EINVAL;
+ }
+ q = qdisc_lookup(dev, tcm->tcm_handle);
+ if (!q)
+ goto create_n_graft;
+ if (n->nlmsg_flags & NLM_F_EXCL) {
+ NL_SET_ERR_MSG(extack, "Exclusivity flag on, cannot override");
+ return -EEXIST;
+ }
+ if (tca[TCA_KIND] &&
+ nla_strcmp(tca[TCA_KIND], q->ops->id)) {
+ NL_SET_ERR_MSG(extack, "Invalid qdisc name");
+ return -EINVAL;
+ }
+ if (q->flags & TCQ_F_INGRESS) {
+ NL_SET_ERR_MSG(extack,
+ "Cannot regraft ingress or clsact Qdiscs");
+ return -EINVAL;
+ }
+ if (q == p ||
+ (p && check_loop(q, p, 0))) {
+ NL_SET_ERR_MSG(extack, "Qdisc parent/child loop detected");
+ return -ELOOP;
+ }
+ if (clid == TC_H_INGRESS) {
+ NL_SET_ERR_MSG(extack, "Ingress cannot graft directly");
+ return -EINVAL;
+ }
+ qdisc_refcount_inc(q);
+ 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:
+ * 1) change it or 2) create/graft new one.
+ * If the requested qdisc kind is different
+ * than the existing one, then we choose graft.
+ * If they are the same then this is "change"
+ * operation - just let it fallthrough..
+ *
+ * 1. We are allowed to create/graft only
+ * if the request is explicitly stating
+ * "please create if it doesn't exist".
+ *
+ * 2. If the request is to exclusive create
+ * then the 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.
+ * This will happen when for example tc
+ * utility issues a "change" command.
+ * Alas, it is sort of hole in API, we
+ * cannot decide what to do unambiguously.
+ * For now we select create/graft.
+ */
+ if (tca[TCA_KIND] &&
+ nla_strcmp(tca[TCA_KIND], q->ops->id)) {
+ if (req_create_or_replace(n) ||
+ req_create_exclusive(n))
+ goto create_n_graft;
+ else if (req_change(n))
+ goto create_n_graft2;
+ }
+ }
+ }
+ } else {
+ if (!tcm->tcm_handle) {
+ NL_SET_ERR_MSG(extack, "Handle cannot be zero");
+ return -EINVAL;
+ }
+ q = qdisc_lookup(dev, tcm->tcm_handle);
+ }
+
+ /* Change qdisc parameters */
+ if (!q) {
+ NL_SET_ERR_MSG(extack, "Specified qdisc not found");
+ return -ENOENT;
+ }
+ if (n->nlmsg_flags & NLM_F_EXCL) {
+ NL_SET_ERR_MSG(extack, "Exclusivity flag on, cannot modify");
+ return -EEXIST;
+ }
+ if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) {
+ NL_SET_ERR_MSG(extack, "Invalid qdisc name");
+ return -EINVAL;
+ }
+ err = qdisc_change(q, tca, extack);
+ if (err == 0)
+ qdisc_notify(net, skb, n, clid, NULL, q, extack);
+ return err;
+
+create_n_graft:
+ if (!(n->nlmsg_flags & NLM_F_CREATE)) {
+ NL_SET_ERR_MSG(extack, "Qdisc not found. To create specify NLM_F_CREATE flag");
+ return -ENOENT;
+ }
+create_n_graft2:
+ if (clid == TC_H_INGRESS) {
+ if (dev_ingress_queue(dev)) {
+ q = qdisc_create(dev, dev_ingress_queue(dev),
+ tcm->tcm_parent, tcm->tcm_parent,
+ tca, &err, extack);
+ } else {
+ NL_SET_ERR_MSG(extack, "Cannot find ingress queue for specified device");
+ 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,
+ tcm->tcm_parent, tcm->tcm_handle,
+ tca, &err, extack);
+ }
+ if (q == NULL) {
+ if (err == -EAGAIN)
+ goto replay;
+ return err;
+ }
+
+graft:
+ err = qdisc_graft(dev, p, skb, n, clid, q, NULL, extack);
+ if (err) {
+ if (q)
+ qdisc_put(q);
+ return err;
+ }
+
+ return 0;
+}
+
+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, bool recur,
+ bool dump_invisible)
+{
+ int ret = 0, q_idx = *q_idx_p;
+ struct Qdisc *q;
+ int b;
+
+ if (!root)
+ return 0;
+
+ q = root;
+ if (q_idx < s_q_idx) {
+ q_idx++;
+ } else {
+ if (!tc_qdisc_dump_ignore(q, dump_invisible) &&
+ tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
+ cb->nlh->nlmsg_seq, NLM_F_MULTI,
+ RTM_NEWQDISC, NULL) <= 0)
+ goto done;
+ q_idx++;
+ }
+
+ /* If dumping singletons, there is no qdisc_dev(root) and the singleton
+ * itself has already been dumped.
+ *
+ * If we've already dumped the top-level (ingress) qdisc above and the global
+ * qdisc hashtable, we don't want to hit it again
+ */
+ if (!qdisc_dev(root) || !recur)
+ goto out;
+
+ hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) {
+ if (q_idx < s_q_idx) {
+ q_idx++;
+ continue;
+ }
+ if (!tc_qdisc_dump_ignore(q, dump_invisible) &&
+ tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
+ cb->nlh->nlmsg_seq, NLM_F_MULTI,
+ RTM_NEWQDISC, NULL) <= 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;
+ const struct nlmsghdr *nlh = cb->nlh;
+ struct nlattr *tca[TCA_MAX + 1];
+ int err;
+
+ s_idx = cb->args[0];
+ s_q_idx = q_idx = cb->args[1];
+
+ idx = 0;
+ ASSERT_RTNL();
+
+ err = nlmsg_parse_deprecated(nlh, sizeof(struct tcmsg), tca, TCA_MAX,
+ rtm_tca_policy, cb->extack);
+ if (err < 0)
+ return err;
+
+ 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(rtnl_dereference(dev->qdisc),
+ skb, cb, &q_idx, s_q_idx,
+ true, tca[TCA_DUMP_INVISIBLE]) < 0)
+ goto done;
+
+ dev_queue = dev_ingress_queue(dev);
+ if (dev_queue &&
+ tc_dump_qdisc_root(rtnl_dereference(dev_queue->qdisc_sleeping),
+ skb, cb, &q_idx, s_q_idx, false,
+ tca[TCA_DUMP_INVISIBLE]) < 0)
+ goto done;
+
+cont:
+ idx++;
+ }
+
+done:
+ cb->args[0] = idx;
+ cb->args[1] = q_idx;
+
+ return skb->len;
+}
+
+
+
+/************************************************
+ * Traffic classes manipulation. *
+ ************************************************/
+
+static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q,
+ unsigned long cl, u32 portid, u32 seq, u16 flags,
+ int event, struct netlink_ext_ack *extack)
+{
+ 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,
+ NULL, &d, TCA_PAD) < 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;
+
+ if (extack && extack->_msg &&
+ nla_put_string(skb, TCA_EXT_WARN_MSG, extack->_msg))
+ goto out_nlmsg_trim;
+
+ 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 netlink_ext_ack *extack)
+{
+ 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, extack) < 0) {
+ kfree_skb(skb);
+ return -EINVAL;
+ }
+
+ return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
+ n->nlmsg_flags & NLM_F_ECHO);
+}
+
+static int tclass_del_notify(struct net *net,
+ const struct Qdisc_class_ops *cops,
+ struct sk_buff *oskb, struct nlmsghdr *n,
+ struct Qdisc *q, unsigned long cl,
+ struct netlink_ext_ack *extack)
+{
+ u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
+ struct sk_buff *skb;
+ int err = 0;
+
+ if (!cops->delete)
+ return -EOPNOTSUPP;
+
+ skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
+ if (!skb)
+ return -ENOBUFS;
+
+ if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0,
+ RTM_DELTCLASS, extack) < 0) {
+ kfree_skb(skb);
+ return -EINVAL;
+ }
+
+ err = cops->delete(q, cl, extack);
+ if (err) {
+ kfree_skb(skb);
+ return err;
+ }
+
+ err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
+ n->nlmsg_flags & NLM_F_ECHO);
+ return err;
+}
+
+#ifdef CONFIG_NET_CLS
+
+struct tcf_bind_args {
+ struct tcf_walker w;
+ unsigned long base;
+ unsigned long cl;
+ u32 classid;
+};
+
+static int tcf_node_bind(struct tcf_proto *tp, void *n, struct tcf_walker *arg)
+{
+ struct tcf_bind_args *a = (void *)arg;
+
+ if (n && tp->ops->bind_class) {
+ struct Qdisc *q = tcf_block_q(tp->chain->block);
+
+ sch_tree_lock(q);
+ tp->ops->bind_class(n, a->classid, a->cl, q, a->base);
+ sch_tree_unlock(q);
+ }
+ return 0;
+}
+
+struct tc_bind_class_args {
+ struct qdisc_walker w;
+ unsigned long new_cl;
+ u32 portid;
+ u32 clid;
+};
+
+static int tc_bind_class_walker(struct Qdisc *q, unsigned long cl,
+ struct qdisc_walker *w)
+{
+ struct tc_bind_class_args *a = (struct tc_bind_class_args *)w;
+ const struct Qdisc_class_ops *cops = q->ops->cl_ops;
+ struct tcf_block *block;
+ struct tcf_chain *chain;
+
+ block = cops->tcf_block(q, cl, NULL);
+ if (!block)
+ return 0;
+ for (chain = tcf_get_next_chain(block, NULL);
+ chain;
+ chain = tcf_get_next_chain(block, chain)) {
+ struct tcf_proto *tp;
+
+ for (tp = tcf_get_next_proto(chain, NULL);
+ tp; tp = tcf_get_next_proto(chain, tp)) {
+ struct tcf_bind_args arg = {};
+
+ arg.w.fn = tcf_node_bind;
+ arg.classid = a->clid;
+ arg.base = cl;
+ arg.cl = a->new_cl;
+ tp->ops->walk(tp, &arg.w, true);
+ }
+ }
+
+ return 0;
+}
+
+static void tc_bind_tclass(struct Qdisc *q, u32 portid, u32 clid,
+ unsigned long new_cl)
+{
+ const struct Qdisc_class_ops *cops = q->ops->cl_ops;
+ struct tc_bind_class_args args = {};
+
+ if (!cops->tcf_block)
+ return;
+ args.portid = portid;
+ args.clid = clid;
+ args.new_cl = new_cl;
+ args.w.fn = tc_bind_class_walker;
+ q->ops->cl_ops->walk(q, &args.w);
+}
+
+#else
+
+static void tc_bind_tclass(struct Qdisc *q, u32 portid, u32 clid,
+ unsigned long new_cl)
+{
+}
+
+#endif
+
+static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n,
+ struct netlink_ext_ack *extack)
+{
+ 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;
+
+ err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX,
+ rtm_tca_policy, extack);
+ 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 = rtnl_dereference(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 = rtnl_dereference(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->find(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 = tclass_del_notify(net, cops, skb, n, q, cl, extack);
+ /* Unbind the class with flilters with 0 */
+ tc_bind_tclass(q, portid, clid, 0);
+ goto out;
+ case RTM_GETTCLASS:
+ err = tclass_notify(net, skb, n, q, cl, RTM_NEWTCLASS, extack);
+ goto out;
+ default:
+ err = -EINVAL;
+ goto out;
+ }
+ }
+
+ if (tca[TCA_INGRESS_BLOCK] || tca[TCA_EGRESS_BLOCK]) {
+ NL_SET_ERR_MSG(extack, "Shared blocks are not supported for classes");
+ return -EOPNOTSUPP;
+ }
+
+ new_cl = cl;
+ err = -EOPNOTSUPP;
+ if (cops->change)
+ err = cops->change(q, clid, portid, tca, &new_cl, extack);
+ if (err == 0) {
+ tclass_notify(net, skb, n, q, new_cl, RTM_NEWTCLASS, extack);
+ /* We just create a new class, need to do reverse binding. */
+ if (cl != new_cl)
+ tc_bind_tclass(q, portid, clid, new_cl);
+ }
+out:
+ return err;
+}
+
+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, NULL);
+}
+
+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, false) ||
+ *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, bool recur)
+{
+ struct Qdisc *q;
+ int b;
+
+ if (!root)
+ return 0;
+
+ if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0)
+ return -1;
+
+ if (!qdisc_dev(root) || !recur)
+ return 0;
+
+ if (tcm->tcm_parent) {
+ q = qdisc_match_from_root(root, TC_H_MAJ(tcm->tcm_parent));
+ if (q && q != root &&
+ tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0)
+ return -1;
+ return 0;
+ }
+ hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) {
+ 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(rtnl_dereference(dev->qdisc),
+ skb, tcm, cb, &t, s_t, true) < 0)
+ goto done;
+
+ dev_queue = dev_ingress_queue(dev);
+ if (dev_queue &&
+ tc_dump_tclass_root(rtnl_dereference(dev_queue->qdisc_sleeping),
+ skb, tcm, cb, &t, s_t, false) < 0)
+ goto done;
+
+done:
+ cb->args[0] = t;
+
+ dev_put(dev);
+ return skb->len;
+}
+
+#ifdef CONFIG_PROC_FS
+static int psched_show(struct seq_file *seq, void *v)
+{
+ seq_printf(seq, "%08x %08x %08x %08x\n",
+ (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1),
+ 1000000,
+ (u32)NSEC_PER_SEC / hrtimer_resolution);
+
+ return 0;
+}
+
+static int __net_init psched_net_init(struct net *net)
+{
+ struct proc_dir_entry *e;
+
+ e = proc_create_single("psched", 0, net->proc_net, psched_show);
+ 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,
+};
+
+#if IS_ENABLED(CONFIG_RETPOLINE)
+DEFINE_STATIC_KEY_FALSE(tc_skip_wrapper);
+#endif
+
+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);
+ register_qdisc(&noqueue_qdisc_ops);
+
+ rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL, 0);
+ rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL, 0);
+ rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc,
+ 0);
+ rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL, 0);
+ rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL, 0);
+ rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass,
+ 0);
+
+ tc_wrapper_init();
+
+ return 0;
+}
+
+subsys_initcall(pktsched_init);