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-rw-r--r--net/sched/sch_taprio.c962
1 files changed, 962 insertions, 0 deletions
diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c
new file mode 100644
index 000000000000..206e4dbed12f
--- /dev/null
+++ b/net/sched/sch_taprio.c
@@ -0,0 +1,962 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/* net/sched/sch_taprio.c Time Aware Priority Scheduler
+ *
+ * Authors: Vinicius Costa Gomes <vinicius.gomes@intel.com>
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/list.h>
+#include <linux/errno.h>
+#include <linux/skbuff.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <net/netlink.h>
+#include <net/pkt_sched.h>
+#include <net/pkt_cls.h>
+#include <net/sch_generic.h>
+
+#define TAPRIO_ALL_GATES_OPEN -1
+
+struct sched_entry {
+ struct list_head list;
+
+ /* The instant that this entry "closes" and the next one
+ * should open, the qdisc will make some effort so that no
+ * packet leaves after this time.
+ */
+ ktime_t close_time;
+ atomic_t budget;
+ int index;
+ u32 gate_mask;
+ u32 interval;
+ u8 command;
+};
+
+struct taprio_sched {
+ struct Qdisc **qdiscs;
+ struct Qdisc *root;
+ s64 base_time;
+ int clockid;
+ int picos_per_byte; /* Using picoseconds because for 10Gbps+
+ * speeds it's sub-nanoseconds per byte
+ */
+ size_t num_entries;
+
+ /* Protects the update side of the RCU protected current_entry */
+ spinlock_t current_entry_lock;
+ struct sched_entry __rcu *current_entry;
+ struct list_head entries;
+ ktime_t (*get_time)(void);
+ struct hrtimer advance_timer;
+};
+
+static int taprio_enqueue(struct sk_buff *skb, struct Qdisc *sch,
+ struct sk_buff **to_free)
+{
+ struct taprio_sched *q = qdisc_priv(sch);
+ struct Qdisc *child;
+ int queue;
+
+ queue = skb_get_queue_mapping(skb);
+
+ child = q->qdiscs[queue];
+ if (unlikely(!child))
+ return qdisc_drop(skb, sch, to_free);
+
+ qdisc_qstats_backlog_inc(sch, skb);
+ sch->q.qlen++;
+
+ return qdisc_enqueue(skb, child, to_free);
+}
+
+static struct sk_buff *taprio_peek(struct Qdisc *sch)
+{
+ struct taprio_sched *q = qdisc_priv(sch);
+ struct net_device *dev = qdisc_dev(sch);
+ struct sched_entry *entry;
+ struct sk_buff *skb;
+ u32 gate_mask;
+ int i;
+
+ rcu_read_lock();
+ entry = rcu_dereference(q->current_entry);
+ gate_mask = entry ? entry->gate_mask : -1;
+ rcu_read_unlock();
+
+ if (!gate_mask)
+ return NULL;
+
+ for (i = 0; i < dev->num_tx_queues; i++) {
+ struct Qdisc *child = q->qdiscs[i];
+ int prio;
+ u8 tc;
+
+ if (unlikely(!child))
+ continue;
+
+ skb = child->ops->peek(child);
+ if (!skb)
+ continue;
+
+ prio = skb->priority;
+ tc = netdev_get_prio_tc_map(dev, prio);
+
+ if (!(gate_mask & BIT(tc)))
+ return NULL;
+
+ return skb;
+ }
+
+ return NULL;
+}
+
+static inline int length_to_duration(struct taprio_sched *q, int len)
+{
+ return (len * q->picos_per_byte) / 1000;
+}
+
+static struct sk_buff *taprio_dequeue(struct Qdisc *sch)
+{
+ struct taprio_sched *q = qdisc_priv(sch);
+ struct net_device *dev = qdisc_dev(sch);
+ struct sched_entry *entry;
+ struct sk_buff *skb;
+ u32 gate_mask;
+ int i;
+
+ rcu_read_lock();
+ entry = rcu_dereference(q->current_entry);
+ /* if there's no entry, it means that the schedule didn't
+ * start yet, so force all gates to be open, this is in
+ * accordance to IEEE 802.1Qbv-2015 Section 8.6.9.4.5
+ * "AdminGateSates"
+ */
+ gate_mask = entry ? entry->gate_mask : TAPRIO_ALL_GATES_OPEN;
+ rcu_read_unlock();
+
+ if (!gate_mask)
+ return NULL;
+
+ for (i = 0; i < dev->num_tx_queues; i++) {
+ struct Qdisc *child = q->qdiscs[i];
+ ktime_t guard;
+ int prio;
+ int len;
+ u8 tc;
+
+ if (unlikely(!child))
+ continue;
+
+ skb = child->ops->peek(child);
+ if (!skb)
+ continue;
+
+ prio = skb->priority;
+ tc = netdev_get_prio_tc_map(dev, prio);
+
+ if (!(gate_mask & BIT(tc)))
+ continue;
+
+ len = qdisc_pkt_len(skb);
+ guard = ktime_add_ns(q->get_time(),
+ length_to_duration(q, len));
+
+ /* In the case that there's no gate entry, there's no
+ * guard band ...
+ */
+ if (gate_mask != TAPRIO_ALL_GATES_OPEN &&
+ ktime_after(guard, entry->close_time))
+ return NULL;
+
+ /* ... and no budget. */
+ if (gate_mask != TAPRIO_ALL_GATES_OPEN &&
+ atomic_sub_return(len, &entry->budget) < 0)
+ return NULL;
+
+ skb = child->ops->dequeue(child);
+ if (unlikely(!skb))
+ return NULL;
+
+ qdisc_bstats_update(sch, skb);
+ qdisc_qstats_backlog_dec(sch, skb);
+ sch->q.qlen--;
+
+ return skb;
+ }
+
+ return NULL;
+}
+
+static bool should_restart_cycle(const struct taprio_sched *q,
+ const struct sched_entry *entry)
+{
+ WARN_ON(!entry);
+
+ return list_is_last(&entry->list, &q->entries);
+}
+
+static enum hrtimer_restart advance_sched(struct hrtimer *timer)
+{
+ struct taprio_sched *q = container_of(timer, struct taprio_sched,
+ advance_timer);
+ struct sched_entry *entry, *next;
+ struct Qdisc *sch = q->root;
+ ktime_t close_time;
+
+ spin_lock(&q->current_entry_lock);
+ entry = rcu_dereference_protected(q->current_entry,
+ lockdep_is_held(&q->current_entry_lock));
+
+ /* This is the case that it's the first time that the schedule
+ * runs, so it only happens once per schedule. The first entry
+ * is pre-calculated during the schedule initialization.
+ */
+ if (unlikely(!entry)) {
+ next = list_first_entry(&q->entries, struct sched_entry,
+ list);
+ close_time = next->close_time;
+ goto first_run;
+ }
+
+ if (should_restart_cycle(q, entry))
+ next = list_first_entry(&q->entries, struct sched_entry,
+ list);
+ else
+ next = list_next_entry(entry, list);
+
+ close_time = ktime_add_ns(entry->close_time, next->interval);
+
+ next->close_time = close_time;
+ atomic_set(&next->budget,
+ (next->interval * 1000) / q->picos_per_byte);
+
+first_run:
+ rcu_assign_pointer(q->current_entry, next);
+ spin_unlock(&q->current_entry_lock);
+
+ hrtimer_set_expires(&q->advance_timer, close_time);
+
+ rcu_read_lock();
+ __netif_schedule(sch);
+ rcu_read_unlock();
+
+ return HRTIMER_RESTART;
+}
+
+static const struct nla_policy entry_policy[TCA_TAPRIO_SCHED_ENTRY_MAX + 1] = {
+ [TCA_TAPRIO_SCHED_ENTRY_INDEX] = { .type = NLA_U32 },
+ [TCA_TAPRIO_SCHED_ENTRY_CMD] = { .type = NLA_U8 },
+ [TCA_TAPRIO_SCHED_ENTRY_GATE_MASK] = { .type = NLA_U32 },
+ [TCA_TAPRIO_SCHED_ENTRY_INTERVAL] = { .type = NLA_U32 },
+};
+
+static const struct nla_policy entry_list_policy[TCA_TAPRIO_SCHED_MAX + 1] = {
+ [TCA_TAPRIO_SCHED_ENTRY] = { .type = NLA_NESTED },
+};
+
+static const struct nla_policy taprio_policy[TCA_TAPRIO_ATTR_MAX + 1] = {
+ [TCA_TAPRIO_ATTR_PRIOMAP] = {
+ .len = sizeof(struct tc_mqprio_qopt)
+ },
+ [TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST] = { .type = NLA_NESTED },
+ [TCA_TAPRIO_ATTR_SCHED_BASE_TIME] = { .type = NLA_S64 },
+ [TCA_TAPRIO_ATTR_SCHED_SINGLE_ENTRY] = { .type = NLA_NESTED },
+ [TCA_TAPRIO_ATTR_SCHED_CLOCKID] = { .type = NLA_S32 },
+};
+
+static int fill_sched_entry(struct nlattr **tb, struct sched_entry *entry,
+ struct netlink_ext_ack *extack)
+{
+ u32 interval = 0;
+
+ if (tb[TCA_TAPRIO_SCHED_ENTRY_CMD])
+ entry->command = nla_get_u8(
+ tb[TCA_TAPRIO_SCHED_ENTRY_CMD]);
+
+ if (tb[TCA_TAPRIO_SCHED_ENTRY_GATE_MASK])
+ entry->gate_mask = nla_get_u32(
+ tb[TCA_TAPRIO_SCHED_ENTRY_GATE_MASK]);
+
+ if (tb[TCA_TAPRIO_SCHED_ENTRY_INTERVAL])
+ interval = nla_get_u32(
+ tb[TCA_TAPRIO_SCHED_ENTRY_INTERVAL]);
+
+ if (interval == 0) {
+ NL_SET_ERR_MSG(extack, "Invalid interval for schedule entry");
+ return -EINVAL;
+ }
+
+ entry->interval = interval;
+
+ return 0;
+}
+
+static int parse_sched_entry(struct nlattr *n, struct sched_entry *entry,
+ int index, struct netlink_ext_ack *extack)
+{
+ struct nlattr *tb[TCA_TAPRIO_SCHED_ENTRY_MAX + 1] = { };
+ int err;
+
+ err = nla_parse_nested(tb, TCA_TAPRIO_SCHED_ENTRY_MAX, n,
+ entry_policy, NULL);
+ if (err < 0) {
+ NL_SET_ERR_MSG(extack, "Could not parse nested entry");
+ return -EINVAL;
+ }
+
+ entry->index = index;
+
+ return fill_sched_entry(tb, entry, extack);
+}
+
+/* Returns the number of entries in case of success */
+static int parse_sched_single_entry(struct nlattr *n,
+ struct taprio_sched *q,
+ struct netlink_ext_ack *extack)
+{
+ struct nlattr *tb_entry[TCA_TAPRIO_SCHED_ENTRY_MAX + 1] = { };
+ struct nlattr *tb_list[TCA_TAPRIO_SCHED_MAX + 1] = { };
+ struct sched_entry *entry;
+ bool found = false;
+ u32 index;
+ int err;
+
+ err = nla_parse_nested(tb_list, TCA_TAPRIO_SCHED_MAX,
+ n, entry_list_policy, NULL);
+ if (err < 0) {
+ NL_SET_ERR_MSG(extack, "Could not parse nested entry");
+ return -EINVAL;
+ }
+
+ if (!tb_list[TCA_TAPRIO_SCHED_ENTRY]) {
+ NL_SET_ERR_MSG(extack, "Single-entry must include an entry");
+ return -EINVAL;
+ }
+
+ err = nla_parse_nested(tb_entry, TCA_TAPRIO_SCHED_ENTRY_MAX,
+ tb_list[TCA_TAPRIO_SCHED_ENTRY],
+ entry_policy, NULL);
+ if (err < 0) {
+ NL_SET_ERR_MSG(extack, "Could not parse nested entry");
+ return -EINVAL;
+ }
+
+ if (!tb_entry[TCA_TAPRIO_SCHED_ENTRY_INDEX]) {
+ NL_SET_ERR_MSG(extack, "Entry must specify an index\n");
+ return -EINVAL;
+ }
+
+ index = nla_get_u32(tb_entry[TCA_TAPRIO_SCHED_ENTRY_INDEX]);
+ if (index >= q->num_entries) {
+ NL_SET_ERR_MSG(extack, "Index for single entry exceeds number of entries in schedule");
+ return -EINVAL;
+ }
+
+ list_for_each_entry(entry, &q->entries, list) {
+ if (entry->index == index) {
+ found = true;
+ break;
+ }
+ }
+
+ if (!found) {
+ NL_SET_ERR_MSG(extack, "Could not find entry");
+ return -ENOENT;
+ }
+
+ err = fill_sched_entry(tb_entry, entry, extack);
+ if (err < 0)
+ return err;
+
+ return q->num_entries;
+}
+
+static int parse_sched_list(struct nlattr *list,
+ struct taprio_sched *q,
+ struct netlink_ext_ack *extack)
+{
+ struct nlattr *n;
+ int err, rem;
+ int i = 0;
+
+ if (!list)
+ return -EINVAL;
+
+ nla_for_each_nested(n, list, rem) {
+ struct sched_entry *entry;
+
+ if (nla_type(n) != TCA_TAPRIO_SCHED_ENTRY) {
+ NL_SET_ERR_MSG(extack, "Attribute is not of type 'entry'");
+ continue;
+ }
+
+ entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry) {
+ NL_SET_ERR_MSG(extack, "Not enough memory for entry");
+ return -ENOMEM;
+ }
+
+ err = parse_sched_entry(n, entry, i, extack);
+ if (err < 0) {
+ kfree(entry);
+ return err;
+ }
+
+ list_add_tail(&entry->list, &q->entries);
+ i++;
+ }
+
+ q->num_entries = i;
+
+ return i;
+}
+
+/* Returns the number of entries in case of success */
+static int parse_taprio_opt(struct nlattr **tb, struct taprio_sched *q,
+ struct netlink_ext_ack *extack)
+{
+ int err = 0;
+ int clockid;
+
+ if (tb[TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST] &&
+ tb[TCA_TAPRIO_ATTR_SCHED_SINGLE_ENTRY])
+ return -EINVAL;
+
+ if (tb[TCA_TAPRIO_ATTR_SCHED_SINGLE_ENTRY] && q->num_entries == 0)
+ return -EINVAL;
+
+ if (q->clockid == -1 && !tb[TCA_TAPRIO_ATTR_SCHED_CLOCKID])
+ return -EINVAL;
+
+ if (tb[TCA_TAPRIO_ATTR_SCHED_BASE_TIME])
+ q->base_time = nla_get_s64(
+ tb[TCA_TAPRIO_ATTR_SCHED_BASE_TIME]);
+
+ if (tb[TCA_TAPRIO_ATTR_SCHED_CLOCKID]) {
+ clockid = nla_get_s32(tb[TCA_TAPRIO_ATTR_SCHED_CLOCKID]);
+
+ /* We only support static clockids and we don't allow
+ * for it to be modified after the first init.
+ */
+ if (clockid < 0 || (q->clockid != -1 && q->clockid != clockid))
+ return -EINVAL;
+
+ q->clockid = clockid;
+ }
+
+ if (tb[TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST])
+ err = parse_sched_list(
+ tb[TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST], q, extack);
+ else if (tb[TCA_TAPRIO_ATTR_SCHED_SINGLE_ENTRY])
+ err = parse_sched_single_entry(
+ tb[TCA_TAPRIO_ATTR_SCHED_SINGLE_ENTRY], q, extack);
+
+ /* parse_sched_* return the number of entries in the schedule,
+ * a schedule with zero entries is an error.
+ */
+ if (err == 0) {
+ NL_SET_ERR_MSG(extack, "The schedule should contain at least one entry");
+ return -EINVAL;
+ }
+
+ return err;
+}
+
+static int taprio_parse_mqprio_opt(struct net_device *dev,
+ struct tc_mqprio_qopt *qopt,
+ struct netlink_ext_ack *extack)
+{
+ int i, j;
+
+ if (!qopt) {
+ NL_SET_ERR_MSG(extack, "'mqprio' configuration is necessary");
+ return -EINVAL;
+ }
+
+ /* Verify num_tc is not out of max range */
+ if (qopt->num_tc > TC_MAX_QUEUE) {
+ NL_SET_ERR_MSG(extack, "Number of traffic classes is outside valid range");
+ return -EINVAL;
+ }
+
+ /* taprio imposes that traffic classes map 1:n to tx queues */
+ if (qopt->num_tc > dev->num_tx_queues) {
+ NL_SET_ERR_MSG(extack, "Number of traffic classes is greater than number of HW queues");
+ 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) {
+ NL_SET_ERR_MSG(extack, "Invalid traffic class in priority to traffic class mapping");
+ return -EINVAL;
+ }
+ }
+
+ 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->num_tx_queues ||
+ !qopt->count[i] ||
+ last > dev->real_num_tx_queues) {
+ NL_SET_ERR_MSG(extack, "Invalid queue in traffic class to queue mapping");
+ 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]) {
+ NL_SET_ERR_MSG(extack, "Detected overlap in the traffic class to queue mapping");
+ return -EINVAL;
+ }
+ }
+ }
+
+ return 0;
+}
+
+static ktime_t taprio_get_start_time(struct Qdisc *sch)
+{
+ struct taprio_sched *q = qdisc_priv(sch);
+ struct sched_entry *entry;
+ ktime_t now, base, cycle;
+ s64 n;
+
+ base = ns_to_ktime(q->base_time);
+ cycle = 0;
+
+ /* Calculate the cycle_time, by summing all the intervals.
+ */
+ list_for_each_entry(entry, &q->entries, list)
+ cycle = ktime_add_ns(cycle, entry->interval);
+
+ if (!cycle)
+ return base;
+
+ now = q->get_time();
+
+ if (ktime_after(base, now))
+ return base;
+
+ /* Schedule the start time for the beginning of the next
+ * cycle.
+ */
+ n = div64_s64(ktime_sub_ns(now, base), cycle);
+
+ return ktime_add_ns(base, (n + 1) * cycle);
+}
+
+static void taprio_start_sched(struct Qdisc *sch, ktime_t start)
+{
+ struct taprio_sched *q = qdisc_priv(sch);
+ struct sched_entry *first;
+ unsigned long flags;
+
+ spin_lock_irqsave(&q->current_entry_lock, flags);
+
+ first = list_first_entry(&q->entries, struct sched_entry,
+ list);
+
+ first->close_time = ktime_add_ns(start, first->interval);
+ atomic_set(&first->budget,
+ (first->interval * 1000) / q->picos_per_byte);
+ rcu_assign_pointer(q->current_entry, NULL);
+
+ spin_unlock_irqrestore(&q->current_entry_lock, flags);
+
+ hrtimer_start(&q->advance_timer, start, HRTIMER_MODE_ABS);
+}
+
+static int taprio_change(struct Qdisc *sch, struct nlattr *opt,
+ struct netlink_ext_ack *extack)
+{
+ struct nlattr *tb[TCA_TAPRIO_ATTR_MAX + 1] = { };
+ struct taprio_sched *q = qdisc_priv(sch);
+ struct net_device *dev = qdisc_dev(sch);
+ struct tc_mqprio_qopt *mqprio = NULL;
+ struct ethtool_link_ksettings ecmd;
+ int i, err, size;
+ s64 link_speed;
+ ktime_t start;
+
+ err = nla_parse_nested(tb, TCA_TAPRIO_ATTR_MAX, opt,
+ taprio_policy, extack);
+ if (err < 0)
+ return err;
+
+ err = -EINVAL;
+ if (tb[TCA_TAPRIO_ATTR_PRIOMAP])
+ mqprio = nla_data(tb[TCA_TAPRIO_ATTR_PRIOMAP]);
+
+ err = taprio_parse_mqprio_opt(dev, mqprio, extack);
+ if (err < 0)
+ return err;
+
+ /* A schedule with less than one entry is an error */
+ size = parse_taprio_opt(tb, q, extack);
+ if (size < 0)
+ return size;
+
+ hrtimer_init(&q->advance_timer, q->clockid, HRTIMER_MODE_ABS);
+ q->advance_timer.function = advance_sched;
+
+ switch (q->clockid) {
+ case CLOCK_REALTIME:
+ q->get_time = ktime_get_real;
+ break;
+ case CLOCK_MONOTONIC:
+ q->get_time = ktime_get;
+ break;
+ case CLOCK_BOOTTIME:
+ q->get_time = ktime_get_boottime;
+ break;
+ case CLOCK_TAI:
+ q->get_time = ktime_get_clocktai;
+ break;
+ default:
+ return -ENOTSUPP;
+ }
+
+ for (i = 0; i < dev->num_tx_queues; i++) {
+ struct netdev_queue *dev_queue;
+ struct Qdisc *qdisc;
+
+ dev_queue = netdev_get_tx_queue(dev, i);
+ qdisc = qdisc_create_dflt(dev_queue,
+ &pfifo_qdisc_ops,
+ TC_H_MAKE(TC_H_MAJ(sch->handle),
+ TC_H_MIN(i + 1)),
+ extack);
+ if (!qdisc)
+ return -ENOMEM;
+
+ if (i < dev->real_num_tx_queues)
+ qdisc_hash_add(qdisc, false);
+
+ q->qdiscs[i] = qdisc;
+ }
+
+ if (mqprio) {
+ netdev_set_num_tc(dev, mqprio->num_tc);
+ for (i = 0; i < mqprio->num_tc; i++)
+ netdev_set_tc_queue(dev, i,
+ mqprio->count[i],
+ mqprio->offset[i]);
+
+ /* Always use supplied priority mappings */
+ for (i = 0; i < TC_BITMASK + 1; i++)
+ netdev_set_prio_tc_map(dev, i,
+ mqprio->prio_tc_map[i]);
+ }
+
+ if (!__ethtool_get_link_ksettings(dev, &ecmd))
+ link_speed = ecmd.base.speed;
+ else
+ link_speed = SPEED_1000;
+
+ q->picos_per_byte = div64_s64(NSEC_PER_SEC * 1000LL * 8,
+ link_speed * 1000 * 1000);
+
+ start = taprio_get_start_time(sch);
+ if (!start)
+ return 0;
+
+ taprio_start_sched(sch, start);
+
+ return 0;
+}
+
+static void taprio_destroy(struct Qdisc *sch)
+{
+ struct taprio_sched *q = qdisc_priv(sch);
+ struct net_device *dev = qdisc_dev(sch);
+ struct sched_entry *entry, *n;
+ unsigned int i;
+
+ hrtimer_cancel(&q->advance_timer);
+
+ if (q->qdiscs) {
+ for (i = 0; i < dev->num_tx_queues && q->qdiscs[i]; i++)
+ qdisc_put(q->qdiscs[i]);
+
+ kfree(q->qdiscs);
+ }
+ q->qdiscs = NULL;
+
+ netdev_set_num_tc(dev, 0);
+
+ list_for_each_entry_safe(entry, n, &q->entries, list) {
+ list_del(&entry->list);
+ kfree(entry);
+ }
+}
+
+static int taprio_init(struct Qdisc *sch, struct nlattr *opt,
+ struct netlink_ext_ack *extack)
+{
+ struct taprio_sched *q = qdisc_priv(sch);
+ struct net_device *dev = qdisc_dev(sch);
+
+ INIT_LIST_HEAD(&q->entries);
+ spin_lock_init(&q->current_entry_lock);
+
+ /* We may overwrite the configuration later */
+ hrtimer_init(&q->advance_timer, CLOCK_TAI, HRTIMER_MODE_ABS);
+
+ q->root = sch;
+
+ /* We only support static clockids. Use an invalid value as default
+ * and get the valid one on taprio_change().
+ */
+ q->clockid = -1;
+
+ if (sch->parent != TC_H_ROOT)
+ return -EOPNOTSUPP;
+
+ if (!netif_is_multiqueue(dev))
+ return -EOPNOTSUPP;
+
+ /* pre-allocate qdisc, attachment can't fail */
+ q->qdiscs = kcalloc(dev->num_tx_queues,
+ sizeof(q->qdiscs[0]),
+ GFP_KERNEL);
+
+ if (!q->qdiscs)
+ return -ENOMEM;
+
+ if (!opt)
+ return -EINVAL;
+
+ return taprio_change(sch, opt, extack);
+}
+
+static struct netdev_queue *taprio_queue_get(struct Qdisc *sch,
+ unsigned long cl)
+{
+ struct net_device *dev = qdisc_dev(sch);
+ unsigned long ntx = cl - 1;
+
+ if (ntx >= dev->num_tx_queues)
+ return NULL;
+
+ return netdev_get_tx_queue(dev, ntx);
+}
+
+static int taprio_graft(struct Qdisc *sch, unsigned long cl,
+ struct Qdisc *new, struct Qdisc **old,
+ struct netlink_ext_ack *extack)
+{
+ struct taprio_sched *q = qdisc_priv(sch);
+ struct net_device *dev = qdisc_dev(sch);
+ struct netdev_queue *dev_queue = taprio_queue_get(sch, cl);
+
+ if (!dev_queue)
+ return -EINVAL;
+
+ if (dev->flags & IFF_UP)
+ dev_deactivate(dev);
+
+ *old = q->qdiscs[cl - 1];
+ q->qdiscs[cl - 1] = new;
+
+ if (new)
+ new->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
+
+ if (dev->flags & IFF_UP)
+ dev_activate(dev);
+
+ return 0;
+}
+
+static int dump_entry(struct sk_buff *msg,
+ const struct sched_entry *entry)
+{
+ struct nlattr *item;
+
+ item = nla_nest_start(msg, TCA_TAPRIO_SCHED_ENTRY);
+ if (!item)
+ return -ENOSPC;
+
+ if (nla_put_u32(msg, TCA_TAPRIO_SCHED_ENTRY_INDEX, entry->index))
+ goto nla_put_failure;
+
+ if (nla_put_u8(msg, TCA_TAPRIO_SCHED_ENTRY_CMD, entry->command))
+ goto nla_put_failure;
+
+ if (nla_put_u32(msg, TCA_TAPRIO_SCHED_ENTRY_GATE_MASK,
+ entry->gate_mask))
+ goto nla_put_failure;
+
+ if (nla_put_u32(msg, TCA_TAPRIO_SCHED_ENTRY_INTERVAL,
+ entry->interval))
+ goto nla_put_failure;
+
+ return nla_nest_end(msg, item);
+
+nla_put_failure:
+ nla_nest_cancel(msg, item);
+ return -1;
+}
+
+static int taprio_dump(struct Qdisc *sch, struct sk_buff *skb)
+{
+ struct taprio_sched *q = qdisc_priv(sch);
+ struct net_device *dev = qdisc_dev(sch);
+ struct tc_mqprio_qopt opt = { 0 };
+ struct nlattr *nest, *entry_list;
+ struct sched_entry *entry;
+ unsigned int i;
+
+ opt.num_tc = netdev_get_num_tc(dev);
+ memcpy(opt.prio_tc_map, dev->prio_tc_map, sizeof(opt.prio_tc_map));
+
+ 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;
+ }
+
+ nest = nla_nest_start(skb, TCA_OPTIONS);
+ if (!nest)
+ return -ENOSPC;
+
+ if (nla_put(skb, TCA_TAPRIO_ATTR_PRIOMAP, sizeof(opt), &opt))
+ goto options_error;
+
+ if (nla_put_s64(skb, TCA_TAPRIO_ATTR_SCHED_BASE_TIME,
+ q->base_time, TCA_TAPRIO_PAD))
+ goto options_error;
+
+ if (nla_put_s32(skb, TCA_TAPRIO_ATTR_SCHED_CLOCKID, q->clockid))
+ goto options_error;
+
+ entry_list = nla_nest_start(skb, TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST);
+ if (!entry_list)
+ goto options_error;
+
+ list_for_each_entry(entry, &q->entries, list) {
+ if (dump_entry(skb, entry) < 0)
+ goto options_error;
+ }
+
+ nla_nest_end(skb, entry_list);
+
+ return nla_nest_end(skb, nest);
+
+options_error:
+ nla_nest_cancel(skb, nest);
+ return -1;
+}
+
+static struct Qdisc *taprio_leaf(struct Qdisc *sch, unsigned long cl)
+{
+ struct netdev_queue *dev_queue = taprio_queue_get(sch, cl);
+
+ if (!dev_queue)
+ return NULL;
+
+ return dev_queue->qdisc_sleeping;
+}
+
+static unsigned long taprio_find(struct Qdisc *sch, u32 classid)
+{
+ unsigned int ntx = TC_H_MIN(classid);
+
+ if (!taprio_queue_get(sch, ntx))
+ return 0;
+ return ntx;
+}
+
+static int taprio_dump_class(struct Qdisc *sch, unsigned long cl,
+ struct sk_buff *skb, struct tcmsg *tcm)
+{
+ struct netdev_queue *dev_queue = taprio_queue_get(sch, cl);
+
+ tcm->tcm_parent = TC_H_ROOT;
+ tcm->tcm_handle |= TC_H_MIN(cl);
+ tcm->tcm_info = dev_queue->qdisc_sleeping->handle;
+
+ return 0;
+}
+
+static int taprio_dump_class_stats(struct Qdisc *sch, unsigned long cl,
+ struct gnet_dump *d)
+ __releases(d->lock)
+ __acquires(d->lock)
+{
+ struct netdev_queue *dev_queue = taprio_queue_get(sch, cl);
+
+ sch = dev_queue->qdisc_sleeping;
+ if (gnet_stats_copy_basic(&sch->running, d, NULL, &sch->bstats) < 0 ||
+ gnet_stats_copy_queue(d, NULL, &sch->qstats, sch->q.qlen) < 0)
+ return -1;
+ return 0;
+}
+
+static void taprio_walk(struct Qdisc *sch, struct qdisc_walker *arg)
+{
+ struct net_device *dev = qdisc_dev(sch);
+ unsigned long ntx;
+
+ if (arg->stop)
+ return;
+
+ arg->count = arg->skip;
+ for (ntx = arg->skip; ntx < dev->num_tx_queues; ntx++) {
+ if (arg->fn(sch, ntx + 1, arg) < 0) {
+ arg->stop = 1;
+ break;
+ }
+ arg->count++;
+ }
+}
+
+static struct netdev_queue *taprio_select_queue(struct Qdisc *sch,
+ struct tcmsg *tcm)
+{
+ return taprio_queue_get(sch, TC_H_MIN(tcm->tcm_parent));
+}
+
+static const struct Qdisc_class_ops taprio_class_ops = {
+ .graft = taprio_graft,
+ .leaf = taprio_leaf,
+ .find = taprio_find,
+ .walk = taprio_walk,
+ .dump = taprio_dump_class,
+ .dump_stats = taprio_dump_class_stats,
+ .select_queue = taprio_select_queue,
+};
+
+static struct Qdisc_ops taprio_qdisc_ops __read_mostly = {
+ .cl_ops = &taprio_class_ops,
+ .id = "taprio",
+ .priv_size = sizeof(struct taprio_sched),
+ .init = taprio_init,
+ .destroy = taprio_destroy,
+ .peek = taprio_peek,
+ .dequeue = taprio_dequeue,
+ .enqueue = taprio_enqueue,
+ .dump = taprio_dump,
+ .owner = THIS_MODULE,
+};
+
+static int __init taprio_module_init(void)
+{
+ return register_qdisc(&taprio_qdisc_ops);
+}
+
+static void __exit taprio_module_exit(void)
+{
+ unregister_qdisc(&taprio_qdisc_ops);
+}
+
+module_init(taprio_module_init);
+module_exit(taprio_module_exit);
+MODULE_LICENSE("GPL");