+++ /dev/null
-From 8a50b65fef0c97bc395ff2166a42ea28e89d2f90 Mon Sep 17 00:00:00 2001
-From: Sasha Levin <sashal@kernel.org>
-Date: Wed, 18 Dec 2019 14:55:13 +0000
-Subject: net: sch_ets: Add a new Qdisc
-
-From: Petr Machata <petrm@mellanox.com>
-
-[ Upstream commit dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33 ]
-
-Introduces a new Qdisc, which is based on 802.1Q-2014 wording. It is
-PRIO-like in how it is configured, meaning one needs to specify how many
-bands there are, how many are strict and how many are dwrr, quanta for the
-latter, and priomap.
-
-The new Qdisc operates like the PRIO / DRR combo would when configured as
-per the standard. The strict classes, if any, are tried for traffic first.
-When there's no traffic in any of the strict queues, the ETS ones (if any)
-are treated in the same way as in DRR.
-
-Signed-off-by: Petr Machata <petrm@mellanox.com>
-Acked-by: Jiri Pirko <jiri@mellanox.com>
-Signed-off-by: David S. Miller <davem@davemloft.net>
-Stable-dep-of: d92adacdd8c2 ("net_sched: ets: fix a race in ets_qdisc_change()")
-Signed-off-by: Sasha Levin <sashal@kernel.org>
----
- include/uapi/linux/pkt_sched.h | 17 +
- net/sched/Kconfig | 17 +
- net/sched/Makefile | 1 +
- net/sched/sch_ets.c | 733 +++++++++++++++++++++++++++++++++
- 4 files changed, 768 insertions(+)
- create mode 100644 net/sched/sch_ets.c
-
-diff --git a/include/uapi/linux/pkt_sched.h b/include/uapi/linux/pkt_sched.h
-index 4a245d7a5c8d6..3933f589118c7 100644
---- a/include/uapi/linux/pkt_sched.h
-+++ b/include/uapi/linux/pkt_sched.h
-@@ -1183,4 +1183,21 @@ enum {
-
- #define TCA_TAPRIO_ATTR_MAX (__TCA_TAPRIO_ATTR_MAX - 1)
-
-+/* ETS */
-+
-+#define TCQ_ETS_MAX_BANDS 16
-+
-+enum {
-+ TCA_ETS_UNSPEC,
-+ TCA_ETS_NBANDS, /* u8 */
-+ TCA_ETS_NSTRICT, /* u8 */
-+ TCA_ETS_QUANTA, /* nested TCA_ETS_QUANTA_BAND */
-+ TCA_ETS_QUANTA_BAND, /* u32 */
-+ TCA_ETS_PRIOMAP, /* nested TCA_ETS_PRIOMAP_BAND */
-+ TCA_ETS_PRIOMAP_BAND, /* u8 */
-+ __TCA_ETS_MAX,
-+};
-+
-+#define TCA_ETS_MAX (__TCA_ETS_MAX - 1)
-+
- #endif
-diff --git a/net/sched/Kconfig b/net/sched/Kconfig
-index 49521aa33ab9f..8b255f8914426 100644
---- a/net/sched/Kconfig
-+++ b/net/sched/Kconfig
-@@ -367,6 +367,23 @@ config NET_SCH_PLUG
- To compile this code as a module, choose M here: the
- module will be called sch_plug.
-
-+config NET_SCH_ETS
-+ tristate "Enhanced transmission selection scheduler (ETS)"
-+ help
-+ The Enhanced Transmission Selection scheduler is a classful
-+ queuing discipline that merges functionality of PRIO and DRR
-+ qdiscs in one scheduler. ETS makes it easy to configure a set of
-+ strict and bandwidth-sharing bands to implement the transmission
-+ selection described in 802.1Qaz.
-+
-+ Say Y here if you want to use the ETS packet scheduling
-+ algorithm.
-+
-+ To compile this driver as a module, choose M here: the module
-+ will be called sch_ets.
-+
-+ If unsure, say N.
-+
- menuconfig NET_SCH_DEFAULT
- bool "Allow override default queue discipline"
- ---help---
-diff --git a/net/sched/Makefile b/net/sched/Makefile
-index e5ea44ec13c58..5b457f80de6db 100644
---- a/net/sched/Makefile
-+++ b/net/sched/Makefile
-@@ -45,6 +45,7 @@ obj-$(CONFIG_NET_SCH_MULTIQ) += sch_multiq.o
- obj-$(CONFIG_NET_SCH_NETEM) += sch_netem.o
- obj-$(CONFIG_NET_SCH_DRR) += sch_drr.o
- obj-$(CONFIG_NET_SCH_PLUG) += sch_plug.o
-+obj-$(CONFIG_NET_SCH_ETS) += sch_ets.o
- obj-$(CONFIG_NET_SCH_MQPRIO) += sch_mqprio.o
- obj-$(CONFIG_NET_SCH_SKBPRIO) += sch_skbprio.o
- obj-$(CONFIG_NET_SCH_CHOKE) += sch_choke.o
-diff --git a/net/sched/sch_ets.c b/net/sched/sch_ets.c
-new file mode 100644
-index 0000000000000..e6194b23e9b0d
---- /dev/null
-+++ b/net/sched/sch_ets.c
-@@ -0,0 +1,733 @@
-+// SPDX-License-Identifier: GPL-2.0-only
-+/*
-+ * net/sched/sch_ets.c Enhanced Transmission Selection scheduler
-+ *
-+ * Description
-+ * -----------
-+ *
-+ * The Enhanced Transmission Selection scheduler is a classful queuing
-+ * discipline that merges functionality of PRIO and DRR qdiscs in one scheduler.
-+ * ETS makes it easy to configure a set of strict and bandwidth-sharing bands to
-+ * implement the transmission selection described in 802.1Qaz.
-+ *
-+ * Although ETS is technically classful, it's not possible to add and remove
-+ * classes at will. Instead one specifies number of classes, how many are
-+ * PRIO-like and how many DRR-like, and quanta for the latter.
-+ *
-+ * Algorithm
-+ * ---------
-+ *
-+ * The strict classes, if any, are tried for traffic first: first band 0, if it
-+ * has no traffic then band 1, etc.
-+ *
-+ * When there is no traffic in any of the strict queues, the bandwidth-sharing
-+ * ones are tried next. Each band is assigned a deficit counter, initialized to
-+ * "quantum" of that band. ETS maintains a list of active bandwidth-sharing
-+ * bands whose qdiscs are non-empty. A packet is dequeued from the band at the
-+ * head of the list if the packet size is smaller or equal to the deficit
-+ * counter. If the counter is too small, it is increased by "quantum" and the
-+ * scheduler moves on to the next band in the active list.
-+ */
-+
-+#include <linux/module.h>
-+#include <net/gen_stats.h>
-+#include <net/netlink.h>
-+#include <net/pkt_cls.h>
-+#include <net/pkt_sched.h>
-+#include <net/sch_generic.h>
-+
-+struct ets_class {
-+ struct list_head alist; /* In struct ets_sched.active. */
-+ struct Qdisc *qdisc;
-+ u32 quantum;
-+ u32 deficit;
-+ struct gnet_stats_basic_packed bstats;
-+ struct gnet_stats_queue qstats;
-+};
-+
-+struct ets_sched {
-+ struct list_head active;
-+ struct tcf_proto __rcu *filter_list;
-+ struct tcf_block *block;
-+ unsigned int nbands;
-+ unsigned int nstrict;
-+ u8 prio2band[TC_PRIO_MAX + 1];
-+ struct ets_class classes[TCQ_ETS_MAX_BANDS];
-+};
-+
-+static const struct nla_policy ets_policy[TCA_ETS_MAX + 1] = {
-+ [TCA_ETS_NBANDS] = { .type = NLA_U8 },
-+ [TCA_ETS_NSTRICT] = { .type = NLA_U8 },
-+ [TCA_ETS_QUANTA] = { .type = NLA_NESTED },
-+ [TCA_ETS_PRIOMAP] = { .type = NLA_NESTED },
-+};
-+
-+static const struct nla_policy ets_priomap_policy[TCA_ETS_MAX + 1] = {
-+ [TCA_ETS_PRIOMAP_BAND] = { .type = NLA_U8 },
-+};
-+
-+static const struct nla_policy ets_quanta_policy[TCA_ETS_MAX + 1] = {
-+ [TCA_ETS_QUANTA_BAND] = { .type = NLA_U32 },
-+};
-+
-+static const struct nla_policy ets_class_policy[TCA_ETS_MAX + 1] = {
-+ [TCA_ETS_QUANTA_BAND] = { .type = NLA_U32 },
-+};
-+
-+static int ets_quantum_parse(struct Qdisc *sch, const struct nlattr *attr,
-+ unsigned int *quantum,
-+ struct netlink_ext_ack *extack)
-+{
-+ *quantum = nla_get_u32(attr);
-+ if (!*quantum) {
-+ NL_SET_ERR_MSG(extack, "ETS quantum cannot be zero");
-+ return -EINVAL;
-+ }
-+ return 0;
-+}
-+
-+static struct ets_class *
-+ets_class_from_arg(struct Qdisc *sch, unsigned long arg)
-+{
-+ struct ets_sched *q = qdisc_priv(sch);
-+
-+ return &q->classes[arg - 1];
-+}
-+
-+static u32 ets_class_id(struct Qdisc *sch, const struct ets_class *cl)
-+{
-+ struct ets_sched *q = qdisc_priv(sch);
-+ int band = cl - q->classes;
-+
-+ return TC_H_MAKE(sch->handle, band + 1);
-+}
-+
-+static bool ets_class_is_strict(struct ets_sched *q, const struct ets_class *cl)
-+{
-+ unsigned int band = cl - q->classes;
-+
-+ return band < q->nstrict;
-+}
-+
-+static int ets_class_change(struct Qdisc *sch, u32 classid, u32 parentid,
-+ struct nlattr **tca, unsigned long *arg,
-+ struct netlink_ext_ack *extack)
-+{
-+ struct ets_class *cl = ets_class_from_arg(sch, *arg);
-+ struct ets_sched *q = qdisc_priv(sch);
-+ struct nlattr *opt = tca[TCA_OPTIONS];
-+ struct nlattr *tb[TCA_ETS_MAX + 1];
-+ unsigned int quantum;
-+ int err;
-+
-+ /* Classes can be added and removed only through Qdisc_ops.change
-+ * interface.
-+ */
-+ if (!cl) {
-+ NL_SET_ERR_MSG(extack, "Fine-grained class addition and removal is not supported");
-+ return -EOPNOTSUPP;
-+ }
-+
-+ if (!opt) {
-+ NL_SET_ERR_MSG(extack, "ETS options are required for this operation");
-+ return -EINVAL;
-+ }
-+
-+ err = nla_parse_nested(tb, TCA_ETS_MAX, opt, ets_class_policy, extack);
-+ if (err < 0)
-+ return err;
-+
-+ if (!tb[TCA_ETS_QUANTA_BAND])
-+ /* Nothing to configure. */
-+ return 0;
-+
-+ if (ets_class_is_strict(q, cl)) {
-+ NL_SET_ERR_MSG(extack, "Strict bands do not have a configurable quantum");
-+ return -EINVAL;
-+ }
-+
-+ err = ets_quantum_parse(sch, tb[TCA_ETS_QUANTA_BAND], &quantum,
-+ extack);
-+ if (err)
-+ return err;
-+
-+ sch_tree_lock(sch);
-+ cl->quantum = quantum;
-+ sch_tree_unlock(sch);
-+ return 0;
-+}
-+
-+static int ets_class_graft(struct Qdisc *sch, unsigned long arg,
-+ struct Qdisc *new, struct Qdisc **old,
-+ struct netlink_ext_ack *extack)
-+{
-+ struct ets_class *cl = ets_class_from_arg(sch, arg);
-+
-+ if (!new) {
-+ new = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
-+ ets_class_id(sch, cl), NULL);
-+ if (!new)
-+ new = &noop_qdisc;
-+ else
-+ qdisc_hash_add(new, true);
-+ }
-+
-+ *old = qdisc_replace(sch, new, &cl->qdisc);
-+ return 0;
-+}
-+
-+static struct Qdisc *ets_class_leaf(struct Qdisc *sch, unsigned long arg)
-+{
-+ struct ets_class *cl = ets_class_from_arg(sch, arg);
-+
-+ return cl->qdisc;
-+}
-+
-+static unsigned long ets_class_find(struct Qdisc *sch, u32 classid)
-+{
-+ unsigned long band = TC_H_MIN(classid);
-+ struct ets_sched *q = qdisc_priv(sch);
-+
-+ if (band - 1 >= q->nbands)
-+ return 0;
-+ return band;
-+}
-+
-+static void ets_class_qlen_notify(struct Qdisc *sch, unsigned long arg)
-+{
-+ struct ets_class *cl = ets_class_from_arg(sch, arg);
-+ struct ets_sched *q = qdisc_priv(sch);
-+
-+ /* We get notified about zero-length child Qdiscs as well if they are
-+ * offloaded. Those aren't on the active list though, so don't attempt
-+ * to remove them.
-+ */
-+ if (!ets_class_is_strict(q, cl) && sch->q.qlen)
-+ list_del(&cl->alist);
-+}
-+
-+static int ets_class_dump(struct Qdisc *sch, unsigned long arg,
-+ struct sk_buff *skb, struct tcmsg *tcm)
-+{
-+ struct ets_class *cl = ets_class_from_arg(sch, arg);
-+ struct ets_sched *q = qdisc_priv(sch);
-+ struct nlattr *nest;
-+
-+ tcm->tcm_parent = TC_H_ROOT;
-+ tcm->tcm_handle = ets_class_id(sch, cl);
-+ tcm->tcm_info = cl->qdisc->handle;
-+
-+ nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
-+ if (!nest)
-+ goto nla_put_failure;
-+ if (!ets_class_is_strict(q, cl)) {
-+ if (nla_put_u32(skb, TCA_ETS_QUANTA_BAND, cl->quantum))
-+ goto nla_put_failure;
-+ }
-+ return nla_nest_end(skb, nest);
-+
-+nla_put_failure:
-+ nla_nest_cancel(skb, nest);
-+ return -EMSGSIZE;
-+}
-+
-+static int ets_class_dump_stats(struct Qdisc *sch, unsigned long arg,
-+ struct gnet_dump *d)
-+{
-+ struct ets_class *cl = ets_class_from_arg(sch, arg);
-+ struct Qdisc *cl_q = cl->qdisc;
-+
-+ if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch),
-+ d, NULL, &cl_q->bstats) < 0 ||
-+ qdisc_qstats_copy(d, cl_q) < 0)
-+ return -1;
-+
-+ return 0;
-+}
-+
-+static void ets_qdisc_walk(struct Qdisc *sch, struct qdisc_walker *arg)
-+{
-+ struct ets_sched *q = qdisc_priv(sch);
-+ int i;
-+
-+ if (arg->stop)
-+ return;
-+
-+ for (i = 0; i < q->nbands; i++) {
-+ if (arg->count < arg->skip) {
-+ arg->count++;
-+ continue;
-+ }
-+ if (arg->fn(sch, i + 1, arg) < 0) {
-+ arg->stop = 1;
-+ break;
-+ }
-+ arg->count++;
-+ }
-+}
-+
-+static struct tcf_block *
-+ets_qdisc_tcf_block(struct Qdisc *sch, unsigned long cl,
-+ struct netlink_ext_ack *extack)
-+{
-+ struct ets_sched *q = qdisc_priv(sch);
-+
-+ if (cl) {
-+ NL_SET_ERR_MSG(extack, "ETS classid must be zero");
-+ return NULL;
-+ }
-+
-+ return q->block;
-+}
-+
-+static unsigned long ets_qdisc_bind_tcf(struct Qdisc *sch, unsigned long parent,
-+ u32 classid)
-+{
-+ return ets_class_find(sch, classid);
-+}
-+
-+static void ets_qdisc_unbind_tcf(struct Qdisc *sch, unsigned long arg)
-+{
-+}
-+
-+static struct ets_class *ets_classify(struct sk_buff *skb, struct Qdisc *sch,
-+ int *qerr)
-+{
-+ struct ets_sched *q = qdisc_priv(sch);
-+ u32 band = skb->priority;
-+ struct tcf_result res;
-+ struct tcf_proto *fl;
-+ int err;
-+
-+ *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
-+ if (TC_H_MAJ(skb->priority) != sch->handle) {
-+ fl = rcu_dereference_bh(q->filter_list);
-+ err = tcf_classify(skb, fl, &res, false);
-+#ifdef CONFIG_NET_CLS_ACT
-+ switch (err) {
-+ case TC_ACT_STOLEN:
-+ case TC_ACT_QUEUED:
-+ case TC_ACT_TRAP:
-+ *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
-+ /* fall through */
-+ case TC_ACT_SHOT:
-+ return NULL;
-+ }
-+#endif
-+ if (!fl || err < 0) {
-+ if (TC_H_MAJ(band))
-+ band = 0;
-+ return &q->classes[q->prio2band[band & TC_PRIO_MAX]];
-+ }
-+ band = res.classid;
-+ }
-+ band = TC_H_MIN(band) - 1;
-+ if (band >= q->nbands)
-+ return &q->classes[q->prio2band[0]];
-+ return &q->classes[band];
-+}
-+
-+static int ets_qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch,
-+ struct sk_buff **to_free)
-+{
-+ unsigned int len = qdisc_pkt_len(skb);
-+ struct ets_sched *q = qdisc_priv(sch);
-+ struct ets_class *cl;
-+ int err = 0;
-+ bool first;
-+
-+ cl = ets_classify(skb, sch, &err);
-+ if (!cl) {
-+ if (err & __NET_XMIT_BYPASS)
-+ qdisc_qstats_drop(sch);
-+ __qdisc_drop(skb, to_free);
-+ return err;
-+ }
-+
-+ first = !cl->qdisc->q.qlen;
-+ err = qdisc_enqueue(skb, cl->qdisc, to_free);
-+ if (unlikely(err != NET_XMIT_SUCCESS)) {
-+ if (net_xmit_drop_count(err)) {
-+ cl->qstats.drops++;
-+ qdisc_qstats_drop(sch);
-+ }
-+ return err;
-+ }
-+
-+ if (first && !ets_class_is_strict(q, cl)) {
-+ list_add_tail(&cl->alist, &q->active);
-+ cl->deficit = cl->quantum;
-+ }
-+
-+ sch->qstats.backlog += len;
-+ sch->q.qlen++;
-+ return err;
-+}
-+
-+static struct sk_buff *
-+ets_qdisc_dequeue_skb(struct Qdisc *sch, struct sk_buff *skb)
-+{
-+ qdisc_bstats_update(sch, skb);
-+ qdisc_qstats_backlog_dec(sch, skb);
-+ sch->q.qlen--;
-+ return skb;
-+}
-+
-+static struct sk_buff *ets_qdisc_dequeue(struct Qdisc *sch)
-+{
-+ struct ets_sched *q = qdisc_priv(sch);
-+ struct ets_class *cl;
-+ struct sk_buff *skb;
-+ unsigned int band;
-+ unsigned int len;
-+
-+ while (1) {
-+ for (band = 0; band < q->nstrict; band++) {
-+ cl = &q->classes[band];
-+ skb = qdisc_dequeue_peeked(cl->qdisc);
-+ if (skb)
-+ return ets_qdisc_dequeue_skb(sch, skb);
-+ }
-+
-+ if (list_empty(&q->active))
-+ goto out;
-+
-+ cl = list_first_entry(&q->active, struct ets_class, alist);
-+ skb = cl->qdisc->ops->peek(cl->qdisc);
-+ if (!skb) {
-+ qdisc_warn_nonwc(__func__, cl->qdisc);
-+ goto out;
-+ }
-+
-+ len = qdisc_pkt_len(skb);
-+ if (len <= cl->deficit) {
-+ cl->deficit -= len;
-+ skb = qdisc_dequeue_peeked(cl->qdisc);
-+ if (unlikely(!skb))
-+ goto out;
-+ if (cl->qdisc->q.qlen == 0)
-+ list_del(&cl->alist);
-+ return ets_qdisc_dequeue_skb(sch, skb);
-+ }
-+
-+ cl->deficit += cl->quantum;
-+ list_move_tail(&cl->alist, &q->active);
-+ }
-+out:
-+ return NULL;
-+}
-+
-+static int ets_qdisc_priomap_parse(struct nlattr *priomap_attr,
-+ unsigned int nbands, u8 *priomap,
-+ struct netlink_ext_ack *extack)
-+{
-+ const struct nlattr *attr;
-+ int prio = 0;
-+ u8 band;
-+ int rem;
-+ int err;
-+
-+ err = __nla_validate_nested(priomap_attr, TCA_ETS_MAX,
-+ ets_priomap_policy, NL_VALIDATE_STRICT,
-+ extack);
-+ if (err)
-+ return err;
-+
-+ nla_for_each_nested(attr, priomap_attr, rem) {
-+ switch (nla_type(attr)) {
-+ case TCA_ETS_PRIOMAP_BAND:
-+ if (prio > TC_PRIO_MAX) {
-+ NL_SET_ERR_MSG_MOD(extack, "Too many priorities in ETS priomap");
-+ return -EINVAL;
-+ }
-+ band = nla_get_u8(attr);
-+ if (band >= nbands) {
-+ NL_SET_ERR_MSG_MOD(extack, "Invalid band number in ETS priomap");
-+ return -EINVAL;
-+ }
-+ priomap[prio++] = band;
-+ break;
-+ default:
-+ WARN_ON_ONCE(1); /* Validate should have caught this. */
-+ return -EINVAL;
-+ }
-+ }
-+
-+ return 0;
-+}
-+
-+static int ets_qdisc_quanta_parse(struct Qdisc *sch, struct nlattr *quanta_attr,
-+ unsigned int nbands, unsigned int nstrict,
-+ unsigned int *quanta,
-+ struct netlink_ext_ack *extack)
-+{
-+ const struct nlattr *attr;
-+ int band = nstrict;
-+ int rem;
-+ int err;
-+
-+ err = __nla_validate_nested(quanta_attr, TCA_ETS_MAX,
-+ ets_quanta_policy, NL_VALIDATE_STRICT,
-+ extack);
-+ if (err < 0)
-+ return err;
-+
-+ nla_for_each_nested(attr, quanta_attr, rem) {
-+ switch (nla_type(attr)) {
-+ case TCA_ETS_QUANTA_BAND:
-+ if (band >= nbands) {
-+ NL_SET_ERR_MSG_MOD(extack, "ETS quanta has more values than bands");
-+ return -EINVAL;
-+ }
-+ err = ets_quantum_parse(sch, attr, &quanta[band++],
-+ extack);
-+ if (err)
-+ return err;
-+ break;
-+ default:
-+ WARN_ON_ONCE(1); /* Validate should have caught this. */
-+ return -EINVAL;
-+ }
-+ }
-+
-+ return 0;
-+}
-+
-+static int ets_qdisc_change(struct Qdisc *sch, struct nlattr *opt,
-+ struct netlink_ext_ack *extack)
-+{
-+ unsigned int quanta[TCQ_ETS_MAX_BANDS] = {0};
-+ struct Qdisc *queues[TCQ_ETS_MAX_BANDS];
-+ struct ets_sched *q = qdisc_priv(sch);
-+ struct nlattr *tb[TCA_ETS_MAX + 1];
-+ unsigned int oldbands = q->nbands;
-+ u8 priomap[TC_PRIO_MAX + 1];
-+ unsigned int nstrict = 0;
-+ unsigned int nbands;
-+ unsigned int i;
-+ int err;
-+
-+ if (!opt) {
-+ NL_SET_ERR_MSG(extack, "ETS options are required for this operation");
-+ return -EINVAL;
-+ }
-+
-+ err = nla_parse_nested(tb, TCA_ETS_MAX, opt, ets_policy, extack);
-+ if (err < 0)
-+ return err;
-+
-+ if (!tb[TCA_ETS_NBANDS]) {
-+ NL_SET_ERR_MSG_MOD(extack, "Number of bands is a required argument");
-+ return -EINVAL;
-+ }
-+ nbands = nla_get_u8(tb[TCA_ETS_NBANDS]);
-+ if (nbands < 1 || nbands > TCQ_ETS_MAX_BANDS) {
-+ NL_SET_ERR_MSG_MOD(extack, "Invalid number of bands");
-+ return -EINVAL;
-+ }
-+ /* Unless overridden, traffic goes to the last band. */
-+ memset(priomap, nbands - 1, sizeof(priomap));
-+
-+ if (tb[TCA_ETS_NSTRICT]) {
-+ nstrict = nla_get_u8(tb[TCA_ETS_NSTRICT]);
-+ if (nstrict > nbands) {
-+ NL_SET_ERR_MSG_MOD(extack, "Invalid number of strict bands");
-+ return -EINVAL;
-+ }
-+ }
-+
-+ if (tb[TCA_ETS_PRIOMAP]) {
-+ err = ets_qdisc_priomap_parse(tb[TCA_ETS_PRIOMAP],
-+ nbands, priomap, extack);
-+ if (err)
-+ return err;
-+ }
-+
-+ if (tb[TCA_ETS_QUANTA]) {
-+ err = ets_qdisc_quanta_parse(sch, tb[TCA_ETS_QUANTA],
-+ nbands, nstrict, quanta, extack);
-+ if (err)
-+ return err;
-+ }
-+ /* If there are more bands than strict + quanta provided, the remaining
-+ * ones are ETS with quantum of MTU. Initialize the missing values here.
-+ */
-+ for (i = nstrict; i < nbands; i++) {
-+ if (!quanta[i])
-+ quanta[i] = psched_mtu(qdisc_dev(sch));
-+ }
-+
-+ /* Before commit, make sure we can allocate all new qdiscs */
-+ for (i = oldbands; i < nbands; i++) {
-+ queues[i] = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
-+ ets_class_id(sch, &q->classes[i]),
-+ extack);
-+ if (!queues[i]) {
-+ while (i > oldbands)
-+ qdisc_put(queues[--i]);
-+ return -ENOMEM;
-+ }
-+ }
-+
-+ sch_tree_lock(sch);
-+
-+ q->nbands = nbands;
-+ q->nstrict = nstrict;
-+ memcpy(q->prio2band, priomap, sizeof(priomap));
-+
-+ for (i = q->nbands; i < oldbands; i++)
-+ qdisc_tree_flush_backlog(q->classes[i].qdisc);
-+
-+ for (i = 0; i < q->nbands; i++)
-+ q->classes[i].quantum = quanta[i];
-+
-+ for (i = oldbands; i < q->nbands; i++) {
-+ q->classes[i].qdisc = queues[i];
-+ if (q->classes[i].qdisc != &noop_qdisc)
-+ qdisc_hash_add(q->classes[i].qdisc, true);
-+ }
-+
-+ sch_tree_unlock(sch);
-+
-+ for (i = q->nbands; i < oldbands; i++) {
-+ qdisc_put(q->classes[i].qdisc);
-+ memset(&q->classes[i], 0, sizeof(q->classes[i]));
-+ }
-+ return 0;
-+}
-+
-+static int ets_qdisc_init(struct Qdisc *sch, struct nlattr *opt,
-+ struct netlink_ext_ack *extack)
-+{
-+ struct ets_sched *q = qdisc_priv(sch);
-+ int err;
-+
-+ if (!opt)
-+ return -EINVAL;
-+
-+ err = tcf_block_get(&q->block, &q->filter_list, sch, extack);
-+ if (err)
-+ return err;
-+
-+ INIT_LIST_HEAD(&q->active);
-+ return ets_qdisc_change(sch, opt, extack);
-+}
-+
-+static void ets_qdisc_reset(struct Qdisc *sch)
-+{
-+ struct ets_sched *q = qdisc_priv(sch);
-+ int band;
-+
-+ for (band = q->nstrict; band < q->nbands; band++) {
-+ if (q->classes[band].qdisc->q.qlen)
-+ list_del(&q->classes[band].alist);
-+ }
-+ for (band = 0; band < q->nbands; band++)
-+ qdisc_reset(q->classes[band].qdisc);
-+ sch->qstats.backlog = 0;
-+ sch->q.qlen = 0;
-+}
-+
-+static void ets_qdisc_destroy(struct Qdisc *sch)
-+{
-+ struct ets_sched *q = qdisc_priv(sch);
-+ int band;
-+
-+ tcf_block_put(q->block);
-+ for (band = 0; band < q->nbands; band++)
-+ qdisc_put(q->classes[band].qdisc);
-+}
-+
-+static int ets_qdisc_dump(struct Qdisc *sch, struct sk_buff *skb)
-+{
-+ struct ets_sched *q = qdisc_priv(sch);
-+ struct nlattr *opts;
-+ struct nlattr *nest;
-+ int band;
-+ int prio;
-+
-+ opts = nla_nest_start_noflag(skb, TCA_OPTIONS);
-+ if (!opts)
-+ goto nla_err;
-+
-+ if (nla_put_u8(skb, TCA_ETS_NBANDS, q->nbands))
-+ goto nla_err;
-+
-+ if (q->nstrict &&
-+ nla_put_u8(skb, TCA_ETS_NSTRICT, q->nstrict))
-+ goto nla_err;
-+
-+ if (q->nbands > q->nstrict) {
-+ nest = nla_nest_start(skb, TCA_ETS_QUANTA);
-+ if (!nest)
-+ goto nla_err;
-+
-+ for (band = q->nstrict; band < q->nbands; band++) {
-+ if (nla_put_u32(skb, TCA_ETS_QUANTA_BAND,
-+ q->classes[band].quantum))
-+ goto nla_err;
-+ }
-+
-+ nla_nest_end(skb, nest);
-+ }
-+
-+ nest = nla_nest_start(skb, TCA_ETS_PRIOMAP);
-+ if (!nest)
-+ goto nla_err;
-+
-+ for (prio = 0; prio <= TC_PRIO_MAX; prio++) {
-+ if (nla_put_u8(skb, TCA_ETS_PRIOMAP_BAND, q->prio2band[prio]))
-+ goto nla_err;
-+ }
-+
-+ nla_nest_end(skb, nest);
-+
-+ return nla_nest_end(skb, opts);
-+
-+nla_err:
-+ nla_nest_cancel(skb, opts);
-+ return -EMSGSIZE;
-+}
-+
-+static const struct Qdisc_class_ops ets_class_ops = {
-+ .change = ets_class_change,
-+ .graft = ets_class_graft,
-+ .leaf = ets_class_leaf,
-+ .find = ets_class_find,
-+ .qlen_notify = ets_class_qlen_notify,
-+ .dump = ets_class_dump,
-+ .dump_stats = ets_class_dump_stats,
-+ .walk = ets_qdisc_walk,
-+ .tcf_block = ets_qdisc_tcf_block,
-+ .bind_tcf = ets_qdisc_bind_tcf,
-+ .unbind_tcf = ets_qdisc_unbind_tcf,
-+};
-+
-+static struct Qdisc_ops ets_qdisc_ops __read_mostly = {
-+ .cl_ops = &ets_class_ops,
-+ .id = "ets",
-+ .priv_size = sizeof(struct ets_sched),
-+ .enqueue = ets_qdisc_enqueue,
-+ .dequeue = ets_qdisc_dequeue,
-+ .peek = qdisc_peek_dequeued,
-+ .change = ets_qdisc_change,
-+ .init = ets_qdisc_init,
-+ .reset = ets_qdisc_reset,
-+ .destroy = ets_qdisc_destroy,
-+ .dump = ets_qdisc_dump,
-+ .owner = THIS_MODULE,
-+};
-+
-+static int __init ets_init(void)
-+{
-+ return register_qdisc(&ets_qdisc_ops);
-+}
-+
-+static void __exit ets_exit(void)
-+{
-+ unregister_qdisc(&ets_qdisc_ops);
-+}
-+
-+module_init(ets_init);
-+module_exit(ets_exit);
-+MODULE_LICENSE("GPL");
---
-2.39.5
-
+++ /dev/null
-From d7fa2ee587e3488c5347dea2fbff0044211dc683 Mon Sep 17 00:00:00 2001
-From: Sasha Levin <sashal@kernel.org>
-Date: Fri, 10 Dec 2021 17:42:47 +0100
-Subject: net/sched: sch_ets: don't remove idle classes from the round-robin
- list
-
-From: Davide Caratti <dcaratti@redhat.com>
-
-[ Upstream commit c062f2a0b04d86c5b8c9d973bea43493eaca3d32 ]
-
-Shuang reported that the following script:
-
- 1) tc qdisc add dev ddd0 handle 10: parent 1: ets bands 8 strict 4 priomap 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7
- 2) mausezahn ddd0 -A 10.10.10.1 -B 10.10.10.2 -c 0 -a own -b 00:c1:a0:c1:a0:00 -t udp &
- 3) tc qdisc change dev ddd0 handle 10: ets bands 4 strict 2 quanta 2500 2500 priomap 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3
-
-crashes systematically when line 2) is commented:
-
- list_del corruption, ffff8e028404bd30->next is LIST_POISON1 (dead000000000100)
- ------------[ cut here ]------------
- kernel BUG at lib/list_debug.c:47!
- invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
- CPU: 0 PID: 954 Comm: tc Not tainted 5.16.0-rc4+ #478
- Hardware name: Red Hat KVM, BIOS 1.11.1-4.module+el8.1.0+4066+0f1aadab 04/01/2014
- RIP: 0010:__list_del_entry_valid.cold.1+0x12/0x47
- Code: fe ff 0f 0b 48 89 c1 4c 89 c6 48 c7 c7 08 42 1b 87 e8 1d c5 fe ff 0f 0b 48 89 fe 48 89 c2 48 c7 c7 98 42 1b 87 e8 09 c5 fe ff <0f> 0b 48 c7 c7 48 43 1b 87 e8 fb c4 fe ff 0f 0b 48 89 f2 48 89 fe
- RSP: 0018:ffffae46807a3888 EFLAGS: 00010246
- RAX: 000000000000004e RBX: 0000000000000007 RCX: 0000000000000202
- RDX: 0000000000000000 RSI: ffffffff871ac536 RDI: 00000000ffffffff
- RBP: ffffae46807a3a10 R08: 0000000000000000 R09: c0000000ffff7fff
- R10: 0000000000000001 R11: ffffae46807a36a8 R12: ffff8e028404b800
- R13: ffff8e028404bd30 R14: dead000000000100 R15: ffff8e02fafa2400
- FS: 00007efdc92e4480(0000) GS:ffff8e02fb600000(0000) knlGS:0000000000000000
- CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
- CR2: 0000000000682f48 CR3: 00000001058be000 CR4: 0000000000350ef0
- Call Trace:
- <TASK>
- ets_qdisc_change+0x58b/0xa70 [sch_ets]
- tc_modify_qdisc+0x323/0x880
- rtnetlink_rcv_msg+0x169/0x4a0
- netlink_rcv_skb+0x50/0x100
- netlink_unicast+0x1a5/0x280
- netlink_sendmsg+0x257/0x4d0
- sock_sendmsg+0x5b/0x60
- ____sys_sendmsg+0x1f2/0x260
- ___sys_sendmsg+0x7c/0xc0
- __sys_sendmsg+0x57/0xa0
- do_syscall_64+0x3a/0x80
- entry_SYSCALL_64_after_hwframe+0x44/0xae
- RIP: 0033:0x7efdc8031338
- Code: 89 02 48 c7 c0 ff ff ff ff eb b5 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 8d 05 25 43 2c 00 8b 00 85 c0 75 17 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 41 54 41 89 d4 55
- RSP: 002b:00007ffdf1ce9828 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
- RAX: ffffffffffffffda RBX: 0000000061b37a97 RCX: 00007efdc8031338
- RDX: 0000000000000000 RSI: 00007ffdf1ce9890 RDI: 0000000000000003
- RBP: 0000000000000000 R08: 0000000000000001 R09: 000000000078a940
- R10: 000000000000000c R11: 0000000000000246 R12: 0000000000000001
- R13: 0000000000688880 R14: 0000000000000000 R15: 0000000000000000
- </TASK>
- Modules linked in: sch_ets sch_tbf dummy rfkill iTCO_wdt iTCO_vendor_support intel_rapl_msr intel_rapl_common joydev pcspkr i2c_i801 virtio_balloon i2c_smbus lpc_ich ip_tables xfs libcrc32c crct10dif_pclmul crc32_pclmul crc32c_intel serio_raw ghash_clmulni_intel ahci libahci libata virtio_blk virtio_console virtio_net net_failover failover sunrpc dm_mirror dm_region_hash dm_log dm_mod [last unloaded: sch_ets]
- ---[ end trace f35878d1912655c2 ]---
- RIP: 0010:__list_del_entry_valid.cold.1+0x12/0x47
- Code: fe ff 0f 0b 48 89 c1 4c 89 c6 48 c7 c7 08 42 1b 87 e8 1d c5 fe ff 0f 0b 48 89 fe 48 89 c2 48 c7 c7 98 42 1b 87 e8 09 c5 fe ff <0f> 0b 48 c7 c7 48 43 1b 87 e8 fb c4 fe ff 0f 0b 48 89 f2 48 89 fe
- RSP: 0018:ffffae46807a3888 EFLAGS: 00010246
- RAX: 000000000000004e RBX: 0000000000000007 RCX: 0000000000000202
- RDX: 0000000000000000 RSI: ffffffff871ac536 RDI: 00000000ffffffff
- RBP: ffffae46807a3a10 R08: 0000000000000000 R09: c0000000ffff7fff
- R10: 0000000000000001 R11: ffffae46807a36a8 R12: ffff8e028404b800
- R13: ffff8e028404bd30 R14: dead000000000100 R15: ffff8e02fafa2400
- FS: 00007efdc92e4480(0000) GS:ffff8e02fb600000(0000) knlGS:0000000000000000
- CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
- CR2: 0000000000682f48 CR3: 00000001058be000 CR4: 0000000000350ef0
- Kernel panic - not syncing: Fatal exception in interrupt
- Kernel Offset: 0x4e00000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
- ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---
-
-we can remove 'q->classes[i].alist' only if DRR class 'i' was part of the
-active list. In the ETS scheduler DRR classes belong to that list only if
-the queue length is greater than zero: we need to test for non-zero value
-of 'q->classes[i].qdisc->q.qlen' before removing from the list, similarly
-to what has been done elsewhere in the ETS code.
-
-Fixes: de6d25924c2a ("net/sched: sch_ets: don't peek at classes beyond 'nbands'")
-Reported-by: Shuang Li <shuali@redhat.com>
-Signed-off-by: Davide Caratti <dcaratti@redhat.com>
-Signed-off-by: David S. Miller <davem@davemloft.net>
-Stable-dep-of: d92adacdd8c2 ("net_sched: ets: fix a race in ets_qdisc_change()")
-Signed-off-by: Sasha Levin <sashal@kernel.org>
----
- net/sched/sch_ets.c | 4 ++--
- 1 file changed, 2 insertions(+), 2 deletions(-)
-
-diff --git a/net/sched/sch_ets.c b/net/sched/sch_ets.c
-index e2c6f87d7ca99..d4a47bb709c5f 100644
---- a/net/sched/sch_ets.c
-+++ b/net/sched/sch_ets.c
-@@ -580,9 +580,9 @@ static int ets_qdisc_change(struct Qdisc *sch, struct nlattr *opt,
- }
- }
- for (i = q->nbands; i < oldbands; i++) {
-- qdisc_tree_flush_backlog(q->classes[i].qdisc);
-- if (i >= q->nstrict)
-+ if (i >= q->nstrict && q->classes[i].qdisc->q.qlen)
- list_del(&q->classes[i].alist);
-+ qdisc_tree_flush_backlog(q->classes[i].qdisc);
- }
- q->nstrict = nstrict;
- memcpy(q->prio2band, priomap, sizeof(priomap));
---
-2.39.5
-
projects / thirdparty / kernel / stable-queue.git / commitdiff
