--- /dev/null
+/*
+ * net/sched/sch_mqprio.c
+ *
+ * Copyright (c) 2010 John Fastabend <john.r.fastabend@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ */
+
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/skbuff.h>
+#include <net/netlink.h>
+#include <net/pkt_sched.h>
+#include <net/sch_generic.h>
+
+struct mqprio_sched {
+ struct Qdisc **qdiscs;
+ int hw_owned;
+};
+
+static void mqprio_destroy(struct Qdisc *sch)
+{
+ struct net_device *dev = qdisc_dev(sch);
+ struct mqprio_sched *priv = qdisc_priv(sch);
+ unsigned int ntx;
+
+ if (!priv->qdiscs)
+ return;
+
+ for (ntx = 0; ntx < dev->num_tx_queues && priv->qdiscs[ntx]; ntx++)
+ qdisc_destroy(priv->qdiscs[ntx]);
+
+ if (priv->hw_owned && dev->netdev_ops->ndo_setup_tc)
+ dev->netdev_ops->ndo_setup_tc(dev, 0);
+ else
+ netdev_set_num_tc(dev, 0);
+
+ kfree(priv->qdiscs);
+}
+
+static int mqprio_parse_opt(struct net_device *dev, struct tc_mqprio_qopt *qopt)
+{
+ int i, j;
+
+ /* Verify num_tc is not out of max range */
+ if (qopt->num_tc > TC_MAX_QUEUE)
+ return -EINVAL;
+
+ /* Verify priority mapping uses valid tcs */
+ for (i = 0; i < TC_BITMASK + 1; i++) {
+ if (qopt->prio_tc_map[i] >= qopt->num_tc)
+ return -EINVAL;
+ }
+
+ /* net_device does not support requested operation */
+ if (qopt->hw && !dev->netdev_ops->ndo_setup_tc)
+ return -EINVAL;
+
+ /* if hw owned qcount and qoffset are taken from LLD so
+ * no reason to verify them here
+ */
+ if (qopt->hw)
+ return 0;
+
+ for (i = 0; i < qopt->num_tc; i++) {
+ unsigned int last = qopt->offset[i] + qopt->count[i];
+
+ /* Verify the queue count is in tx range being equal to the
+ * real_num_tx_queues indicates the last queue is in use.
+ */
+ if (qopt->offset[i] >= dev->real_num_tx_queues ||
+ !qopt->count[i] ||
+ last > dev->real_num_tx_queues)
+ return -EINVAL;
+
+ /* Verify that the offset and counts do not overlap */
+ for (j = i + 1; j < qopt->num_tc; j++) {
+ if (last > qopt->offset[j])
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+
+static int mqprio_init(struct Qdisc *sch, struct nlattr *opt)
+{
+ struct net_device *dev = qdisc_dev(sch);
+ struct mqprio_sched *priv = qdisc_priv(sch);
+ struct netdev_queue *dev_queue;
+ struct Qdisc *qdisc;
+ int i, err = -EOPNOTSUPP;
+ struct tc_mqprio_qopt *qopt = NULL;
+
+ BUILD_BUG_ON(TC_MAX_QUEUE != TC_QOPT_MAX_QUEUE);
+ BUILD_BUG_ON(TC_BITMASK != TC_QOPT_BITMASK);
+
+ if (sch->parent != TC_H_ROOT)
+ return -EOPNOTSUPP;
+
+ if (!netif_is_multiqueue(dev))
+ return -EOPNOTSUPP;
+
+ if (nla_len(opt) < sizeof(*qopt))
+ return -EINVAL;
+
+ qopt = nla_data(opt);
+ if (mqprio_parse_opt(dev, qopt))
+ return -EINVAL;
+
+ /* pre-allocate qdisc, attachment can't fail */
+ priv->qdiscs = kcalloc(dev->num_tx_queues, sizeof(priv->qdiscs[0]),
+ GFP_KERNEL);
+ if (priv->qdiscs == NULL) {
+ err = -ENOMEM;
+ goto err;
+ }
+
+ for (i = 0; i < dev->num_tx_queues; i++) {
+ dev_queue = netdev_get_tx_queue(dev, i);
+ qdisc = qdisc_create_dflt(dev_queue, &pfifo_fast_ops,
+ TC_H_MAKE(TC_H_MAJ(sch->handle),
+ TC_H_MIN(i + 1)));
+ if (qdisc == NULL) {
+ err = -ENOMEM;
+ goto err;
+ }
+ qdisc->flags |= TCQ_F_CAN_BYPASS;
+ priv->qdiscs[i] = qdisc;
+ }
+
+ /* If the mqprio options indicate that hardware should own
+ * the queue mapping then run ndo_setup_tc otherwise use the
+ * supplied and verified mapping
+ */
+ if (qopt->hw) {
+ priv->hw_owned = 1;
+ err = dev->netdev_ops->ndo_setup_tc(dev, qopt->num_tc);
+ if (err)
+ goto err;
+ } else {
+ netdev_set_num_tc(dev, qopt->num_tc);
+ for (i = 0; i < qopt->num_tc; i++)
+ netdev_set_tc_queue(dev, i,
+ qopt->count[i], qopt->offset[i]);
+ }
+
+ /* Always use supplied priority mappings */
+ for (i = 0; i < TC_BITMASK + 1; i++)
+ netdev_set_prio_tc_map(dev, i, qopt->prio_tc_map[i]);
+
+ sch->flags |= TCQ_F_MQROOT;
+ return 0;
+
+err:
+ mqprio_destroy(sch);
+ return err;
+}
+
+static void mqprio_attach(struct Qdisc *sch)
+{
+ struct net_device *dev = qdisc_dev(sch);
+ struct mqprio_sched *priv = qdisc_priv(sch);
+ struct Qdisc *qdisc;
+ unsigned int ntx;
+
+ /* Attach underlying qdisc */
+ for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
+ qdisc = priv->qdiscs[ntx];
+ qdisc = dev_graft_qdisc(qdisc->dev_queue, qdisc);
+ if (qdisc)
+ qdisc_destroy(qdisc);
+ }
+ kfree(priv->qdiscs);
+ priv->qdiscs = NULL;
+}
+
+static struct netdev_queue *mqprio_queue_get(struct Qdisc *sch,
+ unsigned long cl)
+{
+ struct net_device *dev = qdisc_dev(sch);
+ unsigned long ntx = cl - 1 - netdev_get_num_tc(dev);
+
+ if (ntx >= dev->num_tx_queues)
+ return NULL;
+ return netdev_get_tx_queue(dev, ntx);
+}
+
+static int mqprio_graft(struct Qdisc *sch, unsigned long cl, struct Qdisc *new,
+ struct Qdisc **old)
+{
+ struct net_device *dev = qdisc_dev(sch);
+ struct netdev_queue *dev_queue = mqprio_queue_get(sch, cl);
+
+ if (!dev_queue)
+ return -EINVAL;
+
+ if (dev->flags & IFF_UP)
+ dev_deactivate(dev);
+
+ *old = dev_graft_qdisc(dev_queue, new);
+
+ if (dev->flags & IFF_UP)
+ dev_activate(dev);
+
+ return 0;
+}
+
+static int mqprio_dump(struct Qdisc *sch, struct sk_buff *skb)
+{
+ struct net_device *dev = qdisc_dev(sch);
+ struct mqprio_sched *priv = qdisc_priv(sch);
+ unsigned char *b = skb_tail_pointer(skb);
+ struct tc_mqprio_qopt opt;
+ struct Qdisc *qdisc;
+ unsigned int i;
+
+ sch->q.qlen = 0;
+ memset(&sch->bstats, 0, sizeof(sch->bstats));
+ memset(&sch->qstats, 0, sizeof(sch->qstats));
+
+ for (i = 0; i < dev->num_tx_queues; i++) {
+ qdisc = netdev_get_tx_queue(dev, i)->qdisc;
+ spin_lock_bh(qdisc_lock(qdisc));
+ sch->q.qlen += qdisc->q.qlen;
+ sch->bstats.bytes += qdisc->bstats.bytes;
+ sch->bstats.packets += qdisc->bstats.packets;
+ sch->qstats.qlen += qdisc->qstats.qlen;
+ sch->qstats.backlog += qdisc->qstats.backlog;
+ sch->qstats.drops += qdisc->qstats.drops;
+ sch->qstats.requeues += qdisc->qstats.requeues;
+ sch->qstats.overlimits += qdisc->qstats.overlimits;
+ spin_unlock_bh(qdisc_lock(qdisc));
+ }
+
+ opt.num_tc = netdev_get_num_tc(dev);
+ memcpy(opt.prio_tc_map, dev->prio_tc_map, sizeof(opt.prio_tc_map));
+ opt.hw = priv->hw_owned;
+
+ for (i = 0; i < netdev_get_num_tc(dev); i++) {
+ opt.count[i] = dev->tc_to_txq[i].count;
+ opt.offset[i] = dev->tc_to_txq[i].offset;
+ }
+
+ NLA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
+
+ return skb->len;
+nla_put_failure:
+ nlmsg_trim(skb, b);
+ return -1;
+}
+
+static struct Qdisc *mqprio_leaf(struct Qdisc *sch, unsigned long cl)
+{
+ struct netdev_queue *dev_queue = mqprio_queue_get(sch, cl);
+
+ if (!dev_queue)
+ return NULL;
+
+ return dev_queue->qdisc_sleeping;
+}
+
+static unsigned long mqprio_get(struct Qdisc *sch, u32 classid)
+{
+ struct net_device *dev = qdisc_dev(sch);
+ unsigned int ntx = TC_H_MIN(classid);
+
+ if (ntx > dev->num_tx_queues + netdev_get_num_tc(dev))
+ return 0;
+ return ntx;
+}
+
+static void mqprio_put(struct Qdisc *sch, unsigned long cl)
+{
+}
+
+static int mqprio_dump_class(struct Qdisc *sch, unsigned long cl,
+ struct sk_buff *skb, struct tcmsg *tcm)
+{
+ struct net_device *dev = qdisc_dev(sch);
+
+ if (cl <= netdev_get_num_tc(dev)) {
+ tcm->tcm_parent = TC_H_ROOT;
+ tcm->tcm_info = 0;
+ } else {
+ int i;
+ struct netdev_queue *dev_queue;
+
+ dev_queue = mqprio_queue_get(sch, cl);
+ tcm->tcm_parent = 0;
+ for (i = 0; i < netdev_get_num_tc(dev); i++) {
+ struct netdev_tc_txq tc = dev->tc_to_txq[i];
+ int q_idx = cl - netdev_get_num_tc(dev);
+
+ if (q_idx > tc.offset &&
+ q_idx <= tc.offset + tc.count) {
+ tcm->tcm_parent =
+ TC_H_MAKE(TC_H_MAJ(sch->handle),
+ TC_H_MIN(i + 1));
+ break;
+ }
+ }
+ tcm->tcm_info = dev_queue->qdisc_sleeping->handle;
+ }
+ tcm->tcm_handle |= TC_H_MIN(cl);
+ return 0;
+}
+
+static int mqprio_dump_class_stats(struct Qdisc *sch, unsigned long cl,
+ struct gnet_dump *d)
+{
+ struct net_device *dev = qdisc_dev(sch);
+
+ if (cl <= netdev_get_num_tc(dev)) {
+ int i;
+ struct Qdisc *qdisc;
+ struct gnet_stats_queue qstats = {0};
+ struct gnet_stats_basic_packed bstats = {0};
+ struct netdev_tc_txq tc = dev->tc_to_txq[cl - 1];
+
+ /* Drop lock here it will be reclaimed before touching
+ * statistics this is required because the d->lock we
+ * hold here is the look on dev_queue->qdisc_sleeping
+ * also acquired below.
+ */
+ spin_unlock_bh(d->lock);
+
+ for (i = tc.offset; i < tc.offset + tc.count; i++) {
+ qdisc = netdev_get_tx_queue(dev, i)->qdisc;
+ spin_lock_bh(qdisc_lock(qdisc));
+ bstats.bytes += qdisc->bstats.bytes;
+ bstats.packets += qdisc->bstats.packets;
+ qstats.qlen += qdisc->qstats.qlen;
+ qstats.backlog += qdisc->qstats.backlog;
+ qstats.drops += qdisc->qstats.drops;
+ qstats.requeues += qdisc->qstats.requeues;
+ qstats.overlimits += qdisc->qstats.overlimits;
+ spin_unlock_bh(qdisc_lock(qdisc));
+ }
+ /* Reclaim root sleeping lock before completing stats */
+ spin_lock_bh(d->lock);
+ if (gnet_stats_copy_basic(d, &bstats) < 0 ||
+ gnet_stats_copy_queue(d, &qstats) < 0)
+ return -1;
+ } else {
+ struct netdev_queue *dev_queue = mqprio_queue_get(sch, cl);
+
+ sch = dev_queue->qdisc_sleeping;
+ sch->qstats.qlen = sch->q.qlen;
+ if (gnet_stats_copy_basic(d, &sch->bstats) < 0 ||
+ gnet_stats_copy_queue(d, &sch->qstats) < 0)
+ return -1;
+ }
+ return 0;
+}
+
+static void mqprio_walk(struct Qdisc *sch, struct qdisc_walker *arg)
+{
+ struct net_device *dev = qdisc_dev(sch);
+ unsigned long ntx;
+
+ if (arg->stop)
+ return;
+
+ /* Walk hierarchy with a virtual class per tc */
+ arg->count = arg->skip;
+ for (ntx = arg->skip;
+ ntx < dev->num_tx_queues + netdev_get_num_tc(dev);
+ ntx++) {
+ if (arg->fn(sch, ntx + 1, arg) < 0) {
+ arg->stop = 1;
+ break;
+ }
+ arg->count++;
+ }
+}
+
+static const struct Qdisc_class_ops mqprio_class_ops = {
+ .graft = mqprio_graft,
+ .leaf = mqprio_leaf,
+ .get = mqprio_get,
+ .put = mqprio_put,
+ .walk = mqprio_walk,
+ .dump = mqprio_dump_class,
+ .dump_stats = mqprio_dump_class_stats,
+};
+
+struct Qdisc_ops mqprio_qdisc_ops __read_mostly = {
+ .cl_ops = &mqprio_class_ops,
+ .id = "mqprio",
+ .priv_size = sizeof(struct mqprio_sched),
+ .init = mqprio_init,
+ .destroy = mqprio_destroy,
+ .attach = mqprio_attach,
+ .dump = mqprio_dump,
+ .owner = THIS_MODULE,
+};
+
+static int __init mqprio_module_init(void)
+{
+ return register_qdisc(&mqprio_qdisc_ops);
+}
+
+static void __exit mqprio_module_exit(void)
+{
+ unregister_qdisc(&mqprio_qdisc_ops);
+}
+
+module_init(mqprio_module_init);
+module_exit(mqprio_module_exit);
+
+MODULE_LICENSE("GPL");