diff options
Diffstat (limited to 'net/sched/sch_taprio.c')
| -rw-r--r-- | net/sched/sch_taprio.c | 2023 |
1 files changed, 2023 insertions, 0 deletions
diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c new file mode 100644 index 000000000..2d842f31e --- /dev/null +++ b/net/sched/sch_taprio.c @@ -0,0 +1,2023 @@ +// 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/math64.h> +#include <linux/module.h> +#include <linux/spinlock.h> +#include <linux/rcupdate.h> +#include <net/netlink.h> +#include <net/pkt_sched.h> +#include <net/pkt_cls.h> +#include <net/sch_generic.h> +#include <net/sock.h> +#include <net/tcp.h> + +static LIST_HEAD(taprio_list); +static DEFINE_SPINLOCK(taprio_list_lock); + +#define TAPRIO_ALL_GATES_OPEN -1 + +#define TXTIME_ASSIST_IS_ENABLED(flags) ((flags) & TCA_TAPRIO_ATTR_FLAG_TXTIME_ASSIST) +#define FULL_OFFLOAD_IS_ENABLED(flags) ((flags) & TCA_TAPRIO_ATTR_FLAG_FULL_OFFLOAD) +#define TAPRIO_FLAGS_INVALID U32_MAX + +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; + ktime_t next_txtime; + atomic_t budget; + int index; + u32 gate_mask; + u32 interval; + u8 command; +}; + +struct sched_gate_list { + struct rcu_head rcu; + struct list_head entries; + size_t num_entries; + ktime_t cycle_close_time; + s64 cycle_time; + s64 cycle_time_extension; + s64 base_time; +}; + +struct taprio_sched { + struct Qdisc **qdiscs; + struct Qdisc *root; + u32 flags; + enum tk_offsets tk_offset; + int clockid; + bool offloaded; + atomic64_t picos_per_byte; /* Using picoseconds because for 10Gbps+ + * speeds it's sub-nanoseconds per byte + */ + + /* Protects the update side of the RCU protected current_entry */ + spinlock_t current_entry_lock; + struct sched_entry __rcu *current_entry; + struct sched_gate_list __rcu *oper_sched; + struct sched_gate_list __rcu *admin_sched; + struct hrtimer advance_timer; + struct list_head taprio_list; + struct sk_buff *(*dequeue)(struct Qdisc *sch); + struct sk_buff *(*peek)(struct Qdisc *sch); + u32 txtime_delay; +}; + +struct __tc_taprio_qopt_offload { + refcount_t users; + struct tc_taprio_qopt_offload offload; +}; + +static ktime_t sched_base_time(const struct sched_gate_list *sched) +{ + if (!sched) + return KTIME_MAX; + + return ns_to_ktime(sched->base_time); +} + +static ktime_t taprio_mono_to_any(const struct taprio_sched *q, ktime_t mono) +{ + /* This pairs with WRITE_ONCE() in taprio_parse_clockid() */ + enum tk_offsets tk_offset = READ_ONCE(q->tk_offset); + + switch (tk_offset) { + case TK_OFFS_MAX: + return mono; + default: + return ktime_mono_to_any(mono, tk_offset); + } +} + +static ktime_t taprio_get_time(const struct taprio_sched *q) +{ + return taprio_mono_to_any(q, ktime_get()); +} + +static void taprio_free_sched_cb(struct rcu_head *head) +{ + struct sched_gate_list *sched = container_of(head, struct sched_gate_list, rcu); + struct sched_entry *entry, *n; + + if (!sched) + return; + + list_for_each_entry_safe(entry, n, &sched->entries, list) { + list_del(&entry->list); + kfree(entry); + } + + kfree(sched); +} + +static void switch_schedules(struct taprio_sched *q, + struct sched_gate_list **admin, + struct sched_gate_list **oper) +{ + rcu_assign_pointer(q->oper_sched, *admin); + rcu_assign_pointer(q->admin_sched, NULL); + + if (*oper) + call_rcu(&(*oper)->rcu, taprio_free_sched_cb); + + *oper = *admin; + *admin = NULL; +} + +/* Get how much time has been already elapsed in the current cycle. */ +static s32 get_cycle_time_elapsed(struct sched_gate_list *sched, ktime_t time) +{ + ktime_t time_since_sched_start; + s32 time_elapsed; + + time_since_sched_start = ktime_sub(time, sched->base_time); + div_s64_rem(time_since_sched_start, sched->cycle_time, &time_elapsed); + + return time_elapsed; +} + +static ktime_t get_interval_end_time(struct sched_gate_list *sched, + struct sched_gate_list *admin, + struct sched_entry *entry, + ktime_t intv_start) +{ + s32 cycle_elapsed = get_cycle_time_elapsed(sched, intv_start); + ktime_t intv_end, cycle_ext_end, cycle_end; + + cycle_end = ktime_add_ns(intv_start, sched->cycle_time - cycle_elapsed); + intv_end = ktime_add_ns(intv_start, entry->interval); + cycle_ext_end = ktime_add(cycle_end, sched->cycle_time_extension); + + if (ktime_before(intv_end, cycle_end)) + return intv_end; + else if (admin && admin != sched && + ktime_after(admin->base_time, cycle_end) && + ktime_before(admin->base_time, cycle_ext_end)) + return admin->base_time; + else + return cycle_end; +} + +static int length_to_duration(struct taprio_sched *q, int len) +{ + return div_u64(len * atomic64_read(&q->picos_per_byte), 1000); +} + +/* Returns the entry corresponding to next available interval. If + * validate_interval is set, it only validates whether the timestamp occurs + * when the gate corresponding to the skb's traffic class is open. + */ +static struct sched_entry *find_entry_to_transmit(struct sk_buff *skb, + struct Qdisc *sch, + struct sched_gate_list *sched, + struct sched_gate_list *admin, + ktime_t time, + ktime_t *interval_start, + ktime_t *interval_end, + bool validate_interval) +{ + ktime_t curr_intv_start, curr_intv_end, cycle_end, packet_transmit_time; + ktime_t earliest_txtime = KTIME_MAX, txtime, cycle, transmit_end_time; + struct sched_entry *entry = NULL, *entry_found = NULL; + struct taprio_sched *q = qdisc_priv(sch); + struct net_device *dev = qdisc_dev(sch); + bool entry_available = false; + s32 cycle_elapsed; + int tc, n; + + tc = netdev_get_prio_tc_map(dev, skb->priority); + packet_transmit_time = length_to_duration(q, qdisc_pkt_len(skb)); + + *interval_start = 0; + *interval_end = 0; + + if (!sched) + return NULL; + + cycle = sched->cycle_time; + cycle_elapsed = get_cycle_time_elapsed(sched, time); + curr_intv_end = ktime_sub_ns(time, cycle_elapsed); + cycle_end = ktime_add_ns(curr_intv_end, cycle); + + list_for_each_entry(entry, &sched->entries, list) { + curr_intv_start = curr_intv_end; + curr_intv_end = get_interval_end_time(sched, admin, entry, + curr_intv_start); + + if (ktime_after(curr_intv_start, cycle_end)) + break; + + if (!(entry->gate_mask & BIT(tc)) || + packet_transmit_time > entry->interval) + continue; + + txtime = entry->next_txtime; + + if (ktime_before(txtime, time) || validate_interval) { + transmit_end_time = ktime_add_ns(time, packet_transmit_time); + if ((ktime_before(curr_intv_start, time) && + ktime_before(transmit_end_time, curr_intv_end)) || + (ktime_after(curr_intv_start, time) && !validate_interval)) { + entry_found = entry; + *interval_start = curr_intv_start; + *interval_end = curr_intv_end; + break; + } else if (!entry_available && !validate_interval) { + /* Here, we are just trying to find out the + * first available interval in the next cycle. + */ + entry_available = 1; + entry_found = entry; + *interval_start = ktime_add_ns(curr_intv_start, cycle); + *interval_end = ktime_add_ns(curr_intv_end, cycle); + } + } else if (ktime_before(txtime, earliest_txtime) && + !entry_available) { + earliest_txtime = txtime; + entry_found = entry; + n = div_s64(ktime_sub(txtime, curr_intv_start), cycle); + *interval_start = ktime_add(curr_intv_start, n * cycle); + *interval_end = ktime_add(curr_intv_end, n * cycle); + } + } + + return entry_found; +} + +static bool is_valid_interval(struct sk_buff *skb, struct Qdisc *sch) +{ + struct taprio_sched *q = qdisc_priv(sch); + struct sched_gate_list *sched, *admin; + ktime_t interval_start, interval_end; + struct sched_entry *entry; + + rcu_read_lock(); + sched = rcu_dereference(q->oper_sched); + admin = rcu_dereference(q->admin_sched); + + entry = find_entry_to_transmit(skb, sch, sched, admin, skb->tstamp, + &interval_start, &interval_end, true); + rcu_read_unlock(); + + return entry; +} + +static bool taprio_flags_valid(u32 flags) +{ + /* Make sure no other flag bits are set. */ + if (flags & ~(TCA_TAPRIO_ATTR_FLAG_TXTIME_ASSIST | + TCA_TAPRIO_ATTR_FLAG_FULL_OFFLOAD)) + return false; + /* txtime-assist and full offload are mutually exclusive */ + if ((flags & TCA_TAPRIO_ATTR_FLAG_TXTIME_ASSIST) && + (flags & TCA_TAPRIO_ATTR_FLAG_FULL_OFFLOAD)) + return false; + return true; +} + +/* This returns the tstamp value set by TCP in terms of the set clock. */ +static ktime_t get_tcp_tstamp(struct taprio_sched *q, struct sk_buff *skb) +{ + unsigned int offset = skb_network_offset(skb); + const struct ipv6hdr *ipv6h; + const struct iphdr *iph; + struct ipv6hdr _ipv6h; + + ipv6h = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); + if (!ipv6h) + return 0; + + if (ipv6h->version == 4) { + iph = (struct iphdr *)ipv6h; + offset += iph->ihl * 4; + + /* special-case 6in4 tunnelling, as that is a common way to get + * v6 connectivity in the home + */ + if (iph->protocol == IPPROTO_IPV6) { + ipv6h = skb_header_pointer(skb, offset, + sizeof(_ipv6h), &_ipv6h); + + if (!ipv6h || ipv6h->nexthdr != IPPROTO_TCP) + return 0; + } else if (iph->protocol != IPPROTO_TCP) { + return 0; + } + } else if (ipv6h->version == 6 && ipv6h->nexthdr != IPPROTO_TCP) { + return 0; + } + + return taprio_mono_to_any(q, skb->skb_mstamp_ns); +} + +/* There are a few scenarios where we will have to modify the txtime from + * what is read from next_txtime in sched_entry. They are: + * 1. If txtime is in the past, + * a. The gate for the traffic class is currently open and packet can be + * transmitted before it closes, schedule the packet right away. + * b. If the gate corresponding to the traffic class is going to open later + * in the cycle, set the txtime of packet to the interval start. + * 2. If txtime is in the future, there are packets corresponding to the + * current traffic class waiting to be transmitted. So, the following + * possibilities exist: + * a. We can transmit the packet before the window containing the txtime + * closes. + * b. The window might close before the transmission can be completed + * successfully. So, schedule the packet in the next open window. + */ +static long get_packet_txtime(struct sk_buff *skb, struct Qdisc *sch) +{ + ktime_t transmit_end_time, interval_end, interval_start, tcp_tstamp; + struct taprio_sched *q = qdisc_priv(sch); + struct sched_gate_list *sched, *admin; + ktime_t minimum_time, now, txtime; + int len, packet_transmit_time; + struct sched_entry *entry; + bool sched_changed; + + now = taprio_get_time(q); + minimum_time = ktime_add_ns(now, q->txtime_delay); + + tcp_tstamp = get_tcp_tstamp(q, skb); + minimum_time = max_t(ktime_t, minimum_time, tcp_tstamp); + + rcu_read_lock(); + admin = rcu_dereference(q->admin_sched); + sched = rcu_dereference(q->oper_sched); + if (admin && ktime_after(minimum_time, admin->base_time)) + switch_schedules(q, &admin, &sched); + + /* Until the schedule starts, all the queues are open */ + if (!sched || ktime_before(minimum_time, sched->base_time)) { + txtime = minimum_time; + goto done; + } + + len = qdisc_pkt_len(skb); + packet_transmit_time = length_to_duration(q, len); + + do { + sched_changed = 0; + + entry = find_entry_to_transmit(skb, sch, sched, admin, + minimum_time, + &interval_start, &interval_end, + false); + if (!entry) { + txtime = 0; + goto done; + } + + txtime = entry->next_txtime; + txtime = max_t(ktime_t, txtime, minimum_time); + txtime = max_t(ktime_t, txtime, interval_start); + + if (admin && admin != sched && + ktime_after(txtime, admin->base_time)) { + sched = admin; + sched_changed = 1; + continue; + } + + transmit_end_time = ktime_add(txtime, packet_transmit_time); + minimum_time = transmit_end_time; + + /* Update the txtime of current entry to the next time it's + * interval starts. + */ + if (ktime_after(transmit_end_time, interval_end)) + entry->next_txtime = ktime_add(interval_start, sched->cycle_time); + } while (sched_changed || ktime_after(transmit_end_time, interval_end)); + + entry->next_txtime = transmit_end_time; + +done: + rcu_read_unlock(); + return txtime; +} + +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); + + /* sk_flags are only safe to use on full sockets. */ + if (skb->sk && sk_fullsock(skb->sk) && sock_flag(skb->sk, SOCK_TXTIME)) { + if (!is_valid_interval(skb, sch)) + return qdisc_drop(skb, sch, to_free); + } else if (TXTIME_ASSIST_IS_ENABLED(q->flags)) { + skb->tstamp = get_packet_txtime(skb, sch); + if (!skb->tstamp) + 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_soft(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 : 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]; + int prio; + u8 tc; + + if (unlikely(!child)) + continue; + + skb = child->ops->peek(child); + if (!skb) + continue; + + if (TXTIME_ASSIST_IS_ENABLED(q->flags)) + return skb; + + prio = skb->priority; + tc = netdev_get_prio_tc_map(dev, prio); + + if (!(gate_mask & BIT(tc))) + continue; + + return skb; + } + + return NULL; +} + +static struct sk_buff *taprio_peek_offload(struct Qdisc *sch) +{ + struct taprio_sched *q = qdisc_priv(sch); + struct net_device *dev = qdisc_dev(sch); + struct sk_buff *skb; + int i; + + for (i = 0; i < dev->num_tx_queues; i++) { + struct Qdisc *child = q->qdiscs[i]; + + if (unlikely(!child)) + continue; + + skb = child->ops->peek(child); + if (!skb) + continue; + + return skb; + } + + return NULL; +} + +static struct sk_buff *taprio_peek(struct Qdisc *sch) +{ + struct taprio_sched *q = qdisc_priv(sch); + + return q->peek(sch); +} + +static void taprio_set_budget(struct taprio_sched *q, struct sched_entry *entry) +{ + atomic_set(&entry->budget, + div64_u64((u64)entry->interval * 1000, + atomic64_read(&q->picos_per_byte))); +} + +static struct sk_buff *taprio_dequeue_soft(struct Qdisc *sch) +{ + struct taprio_sched *q = qdisc_priv(sch); + struct net_device *dev = qdisc_dev(sch); + struct sk_buff *skb = NULL; + struct sched_entry *entry; + 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; + + if (!gate_mask) + goto done; + + 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; + + if (TXTIME_ASSIST_IS_ENABLED(q->flags)) { + skb = child->ops->dequeue(child); + if (!skb) + continue; + goto skb_found; + } + + skb = child->ops->peek(child); + if (!skb) + continue; + + prio = skb->priority; + tc = netdev_get_prio_tc_map(dev, prio); + + if (!(gate_mask & BIT(tc))) { + skb = NULL; + continue; + } + + len = qdisc_pkt_len(skb); + guard = ktime_add_ns(taprio_get_time(q), + 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)) { + skb = NULL; + continue; + } + + /* ... and no budget. */ + if (gate_mask != TAPRIO_ALL_GATES_OPEN && + atomic_sub_return(len, &entry->budget) < 0) { + skb = NULL; + continue; + } + + skb = child->ops->dequeue(child); + if (unlikely(!skb)) + goto done; + +skb_found: + qdisc_bstats_update(sch, skb); + qdisc_qstats_backlog_dec(sch, skb); + sch->q.qlen--; + + goto done; + } + +done: + rcu_read_unlock(); + + return skb; +} + +static struct sk_buff *taprio_dequeue_offload(struct Qdisc *sch) +{ + struct taprio_sched *q = qdisc_priv(sch); + struct net_device *dev = qdisc_dev(sch); + struct sk_buff *skb; + int i; + + for (i = 0; i < dev->num_tx_queues; i++) { + struct Qdisc *child = q->qdiscs[i]; + + if (unlikely(!child)) + continue; + + skb = child->ops->dequeue(child); + if (unlikely(!skb)) + continue; + + qdisc_bstats_update(sch, skb); + qdisc_qstats_backlog_dec(sch, skb); + sch->q.qlen--; + + return skb; + } + + return NULL; +} + +static struct sk_buff *taprio_dequeue(struct Qdisc *sch) +{ + struct taprio_sched *q = qdisc_priv(sch); + + return q->dequeue(sch); +} + +static bool should_restart_cycle(const struct sched_gate_list *oper, + const struct sched_entry *entry) +{ + if (list_is_last(&entry->list, &oper->entries)) + return true; + + if (ktime_compare(entry->close_time, oper->cycle_close_time) == 0) + return true; + + return false; +} + +static bool should_change_schedules(const struct sched_gate_list *admin, + const struct sched_gate_list *oper, + ktime_t close_time) +{ + ktime_t next_base_time, extension_time; + + if (!admin) + return false; + + next_base_time = sched_base_time(admin); + + /* This is the simple case, the close_time would fall after + * the next schedule base_time. + */ + if (ktime_compare(next_base_time, close_time) <= 0) + return true; + + /* This is the cycle_time_extension case, if the close_time + * plus the amount that can be extended would fall after the + * next schedule base_time, we can extend the current schedule + * for that amount. + */ + extension_time = ktime_add_ns(close_time, oper->cycle_time_extension); + + /* FIXME: the IEEE 802.1Q-2018 Specification isn't clear about + * how precisely the extension should be made. So after + * conformance testing, this logic may change. + */ + if (ktime_compare(next_base_time, extension_time) <= 0) + return true; + + return false; +} + +static enum hrtimer_restart advance_sched(struct hrtimer *timer) +{ + struct taprio_sched *q = container_of(timer, struct taprio_sched, + advance_timer); + struct sched_gate_list *oper, *admin; + 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)); + oper = rcu_dereference_protected(q->oper_sched, + lockdep_is_held(&q->current_entry_lock)); + admin = rcu_dereference_protected(q->admin_sched, + lockdep_is_held(&q->current_entry_lock)); + + if (!oper) + switch_schedules(q, &admin, &oper); + + /* This can happen in two cases: 1. this is the very first run + * of this function (i.e. we weren't running any schedule + * previously); 2. The previous schedule just ended. The first + * entry of all schedules are pre-calculated during the + * schedule initialization. + */ + if (unlikely(!entry || entry->close_time == oper->base_time)) { + next = list_first_entry(&oper->entries, struct sched_entry, + list); + close_time = next->close_time; + goto first_run; + } + + if (should_restart_cycle(oper, entry)) { + next = list_first_entry(&oper->entries, struct sched_entry, + list); + oper->cycle_close_time = ktime_add_ns(oper->cycle_close_time, + oper->cycle_time); + } else { + next = list_next_entry(entry, list); + } + + close_time = ktime_add_ns(entry->close_time, next->interval); + close_time = min_t(ktime_t, close_time, oper->cycle_close_time); + + if (should_change_schedules(admin, oper, close_time)) { + /* Set things so the next time this runs, the new + * schedule runs. + */ + close_time = sched_base_time(admin); + switch_schedules(q, &admin, &oper); + } + + next->close_time = close_time; + taprio_set_budget(q, next); + +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 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 }, + [TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME] = { .type = NLA_S64 }, + [TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME_EXTENSION] = { .type = NLA_S64 }, + [TCA_TAPRIO_ATTR_FLAGS] = { .type = NLA_U32 }, + [TCA_TAPRIO_ATTR_TXTIME_DELAY] = { .type = NLA_U32 }, +}; + +static int fill_sched_entry(struct taprio_sched *q, struct nlattr **tb, + struct sched_entry *entry, + struct netlink_ext_ack *extack) +{ + int min_duration = length_to_duration(q, ETH_ZLEN); + 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]); + + /* The interval should allow at least the minimum ethernet + * frame to go out. + */ + if (interval < min_duration) { + NL_SET_ERR_MSG(extack, "Invalid interval for schedule entry"); + return -EINVAL; + } + + entry->interval = interval; + + return 0; +} + +static int parse_sched_entry(struct taprio_sched *q, 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_deprecated(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(q, tb, entry, extack); +} + +static int parse_sched_list(struct taprio_sched *q, struct nlattr *list, + struct sched_gate_list *sched, + 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(q, n, entry, i, extack); + if (err < 0) { + kfree(entry); + return err; + } + + list_add_tail(&entry->list, &sched->entries); + i++; + } + + sched->num_entries = i; + + return i; +} + +static int parse_taprio_schedule(struct taprio_sched *q, struct nlattr **tb, + struct sched_gate_list *new, + struct netlink_ext_ack *extack) +{ + int err = 0; + + if (tb[TCA_TAPRIO_ATTR_SCHED_SINGLE_ENTRY]) { + NL_SET_ERR_MSG(extack, "Adding a single entry is not supported"); + return -ENOTSUPP; + } + + if (tb[TCA_TAPRIO_ATTR_SCHED_BASE_TIME]) + new->base_time = nla_get_s64(tb[TCA_TAPRIO_ATTR_SCHED_BASE_TIME]); + + if (tb[TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME_EXTENSION]) + new->cycle_time_extension = nla_get_s64(tb[TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME_EXTENSION]); + + if (tb[TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME]) + new->cycle_time = nla_get_s64(tb[TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME]); + + if (tb[TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST]) + err = parse_sched_list(q, tb[TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST], + new, extack); + if (err < 0) + return err; + + if (!new->cycle_time) { + struct sched_entry *entry; + ktime_t cycle = 0; + + list_for_each_entry(entry, &new->entries, list) + cycle = ktime_add_ns(cycle, entry->interval); + + if (!cycle) { + NL_SET_ERR_MSG(extack, "'cycle_time' can never be 0"); + return -EINVAL; + } + + new->cycle_time = cycle; + } + + return 0; +} + +static int taprio_parse_mqprio_opt(struct net_device *dev, + struct tc_mqprio_qopt *qopt, + struct netlink_ext_ack *extack, + u32 taprio_flags) +{ + int i, j; + + if (!qopt && !dev->num_tc) { + NL_SET_ERR_MSG(extack, "'mqprio' configuration is necessary"); + return -EINVAL; + } + + /* If num_tc is already set, it means that the user already + * configured the mqprio part + */ + if (dev->num_tc) + return 0; + + /* 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; 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; + } + + if (TXTIME_ASSIST_IS_ENABLED(taprio_flags)) + continue; + + /* 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 int taprio_get_start_time(struct Qdisc *sch, + struct sched_gate_list *sched, + ktime_t *start) +{ + struct taprio_sched *q = qdisc_priv(sch); + ktime_t now, base, cycle; + s64 n; + + base = sched_base_time(sched); + now = taprio_get_time(q); + + if (ktime_after(base, now)) { + *start = base; + return 0; + } + + cycle = sched->cycle_time; + + /* The qdisc is expected to have at least one sched_entry. Moreover, + * any entry must have 'interval' > 0. Thus if the cycle time is zero, + * something went really wrong. In that case, we should warn about this + * inconsistent state and return error. + */ + if (WARN_ON(!cycle)) + return -EFAULT; + + /* Schedule the start time for the beginning of the next + * cycle. + */ + n = div64_s64(ktime_sub_ns(now, base), cycle); + *start = ktime_add_ns(base, (n + 1) * cycle); + return 0; +} + +static void setup_first_close_time(struct taprio_sched *q, + struct sched_gate_list *sched, ktime_t base) +{ + struct sched_entry *first; + ktime_t cycle; + + first = list_first_entry(&sched->entries, + struct sched_entry, list); + + cycle = sched->cycle_time; + + /* FIXME: find a better place to do this */ + sched->cycle_close_time = ktime_add_ns(base, cycle); + + first->close_time = ktime_add_ns(base, first->interval); + taprio_set_budget(q, first); + rcu_assign_pointer(q->current_entry, NULL); +} + +static void taprio_start_sched(struct Qdisc *sch, + ktime_t start, struct sched_gate_list *new) +{ + struct taprio_sched *q = qdisc_priv(sch); + ktime_t expires; + + if (FULL_OFFLOAD_IS_ENABLED(q->flags)) + return; + + expires = hrtimer_get_expires(&q->advance_timer); + if (expires == 0) + expires = KTIME_MAX; + + /* If the new schedule starts before the next expiration, we + * reprogram it to the earliest one, so we change the admin + * schedule to the operational one at the right time. + */ + start = min_t(ktime_t, start, expires); + + hrtimer_start(&q->advance_timer, start, HRTIMER_MODE_ABS); +} + +static void taprio_set_picos_per_byte(struct net_device *dev, + struct taprio_sched *q) +{ + struct ethtool_link_ksettings ecmd; + int speed = SPEED_10; + int picos_per_byte; + int err; + + err = __ethtool_get_link_ksettings(dev, &ecmd); + if (err < 0) + goto skip; + + if (ecmd.base.speed && ecmd.base.speed != SPEED_UNKNOWN) + speed = ecmd.base.speed; + +skip: + picos_per_byte = (USEC_PER_SEC * 8) / speed; + + atomic64_set(&q->picos_per_byte, picos_per_byte); + netdev_dbg(dev, "taprio: set %s's picos_per_byte to: %lld, linkspeed: %d\n", + dev->name, (long long)atomic64_read(&q->picos_per_byte), + ecmd.base.speed); +} + +static int taprio_dev_notifier(struct notifier_block *nb, unsigned long event, + void *ptr) +{ + struct net_device *dev = netdev_notifier_info_to_dev(ptr); + struct net_device *qdev; + struct taprio_sched *q; + bool found = false; + + ASSERT_RTNL(); + + if (event != NETDEV_UP && event != NETDEV_CHANGE) + return NOTIFY_DONE; + + spin_lock(&taprio_list_lock); + list_for_each_entry(q, &taprio_list, taprio_list) { + qdev = qdisc_dev(q->root); + if (qdev == dev) { + found = true; + break; + } + } + spin_unlock(&taprio_list_lock); + + if (found) + taprio_set_picos_per_byte(dev, q); + + return NOTIFY_DONE; +} + +static void setup_txtime(struct taprio_sched *q, + struct sched_gate_list *sched, ktime_t base) +{ + struct sched_entry *entry; + u32 interval = 0; + + list_for_each_entry(entry, &sched->entries, list) { + entry->next_txtime = ktime_add_ns(base, interval); + interval += entry->interval; + } +} + +static struct tc_taprio_qopt_offload *taprio_offload_alloc(int num_entries) +{ + struct __tc_taprio_qopt_offload *__offload; + + __offload = kzalloc(struct_size(__offload, offload.entries, num_entries), + GFP_KERNEL); + if (!__offload) + return NULL; + + refcount_set(&__offload->users, 1); + + return &__offload->offload; +} + +struct tc_taprio_qopt_offload *taprio_offload_get(struct tc_taprio_qopt_offload + *offload) +{ + struct __tc_taprio_qopt_offload *__offload; + + __offload = container_of(offload, struct __tc_taprio_qopt_offload, + offload); + + refcount_inc(&__offload->users); + + return offload; +} +EXPORT_SYMBOL_GPL(taprio_offload_get); + +void taprio_offload_free(struct tc_taprio_qopt_offload *offload) +{ + struct __tc_taprio_qopt_offload *__offload; + + __offload = container_of(offload, struct __tc_taprio_qopt_offload, + offload); + + if (!refcount_dec_and_test(&__offload->users)) + return; + + kfree(__offload); +} +EXPORT_SYMBOL_GPL(taprio_offload_free); + +/* The function will only serve to keep the pointers to the "oper" and "admin" + * schedules valid in relation to their base times, so when calling dump() the + * users looks at the right schedules. + * When using full offload, the admin configuration is promoted to oper at the + * base_time in the PHC time domain. But because the system time is not + * necessarily in sync with that, we can't just trigger a hrtimer to call + * switch_schedules at the right hardware time. + * At the moment we call this by hand right away from taprio, but in the future + * it will be useful to create a mechanism for drivers to notify taprio of the + * offload state (PENDING, ACTIVE, INACTIVE) so it can be visible in dump(). + * This is left as TODO. + */ +static void taprio_offload_config_changed(struct taprio_sched *q) +{ + struct sched_gate_list *oper, *admin; + + spin_lock(&q->current_entry_lock); + + oper = rcu_dereference_protected(q->oper_sched, + lockdep_is_held(&q->current_entry_lock)); + admin = rcu_dereference_protected(q->admin_sched, + lockdep_is_held(&q->current_entry_lock)); + + switch_schedules(q, &admin, &oper); + + spin_unlock(&q->current_entry_lock); +} + +static u32 tc_map_to_queue_mask(struct net_device *dev, u32 tc_mask) +{ + u32 i, queue_mask = 0; + + for (i = 0; i < dev->num_tc; i++) { + u32 offset, count; + + if (!(tc_mask & BIT(i))) + continue; + + offset = dev->tc_to_txq[i].offset; + count = dev->tc_to_txq[i].count; + + queue_mask |= GENMASK(offset + count - 1, offset); + } + + return queue_mask; +} + +static void taprio_sched_to_offload(struct net_device *dev, + struct sched_gate_list *sched, + struct tc_taprio_qopt_offload *offload) +{ + struct sched_entry *entry; + int i = 0; + + offload->base_time = sched->base_time; + offload->cycle_time = sched->cycle_time; + offload->cycle_time_extension = sched->cycle_time_extension; + + list_for_each_entry(entry, &sched->entries, list) { + struct tc_taprio_sched_entry *e = &offload->entries[i]; + + e->command = entry->command; + e->interval = entry->interval; + e->gate_mask = tc_map_to_queue_mask(dev, entry->gate_mask); + + i++; + } + + offload->num_entries = i; +} + +static int taprio_enable_offload(struct net_device *dev, + struct taprio_sched *q, + struct sched_gate_list *sched, + struct netlink_ext_ack *extack) +{ + const struct net_device_ops *ops = dev->netdev_ops; + struct tc_taprio_qopt_offload *offload; + int err = 0; + + if (!ops->ndo_setup_tc) { + NL_SET_ERR_MSG(extack, + "Device does not support taprio offload"); + return -EOPNOTSUPP; + } + + offload = taprio_offload_alloc(sched->num_entries); + if (!offload) { + NL_SET_ERR_MSG(extack, + "Not enough memory for enabling offload mode"); + return -ENOMEM; + } + offload->enable = 1; + taprio_sched_to_offload(dev, sched, offload); + + err = ops->ndo_setup_tc(dev, TC_SETUP_QDISC_TAPRIO, offload); + if (err < 0) { + NL_SET_ERR_MSG(extack, + "Device failed to setup taprio offload"); + goto done; + } + + q->offloaded = true; + +done: + taprio_offload_free(offload); + + return err; +} + +static int taprio_disable_offload(struct net_device *dev, + struct taprio_sched *q, + struct netlink_ext_ack *extack) +{ + const struct net_device_ops *ops = dev->netdev_ops; + struct tc_taprio_qopt_offload *offload; + int err; + + if (!q->offloaded) + return 0; + + offload = taprio_offload_alloc(0); + if (!offload) { + NL_SET_ERR_MSG(extack, + "Not enough memory to disable offload mode"); + return -ENOMEM; + } + offload->enable = 0; + + err = ops->ndo_setup_tc(dev, TC_SETUP_QDISC_TAPRIO, offload); + if (err < 0) { + NL_SET_ERR_MSG(extack, + "Device failed to disable offload"); + goto out; + } + + q->offloaded = false; + +out: + taprio_offload_free(offload); + + return err; +} + +/* If full offload is enabled, the only possible clockid is the net device's + * PHC. For that reason, specifying a clockid through netlink is incorrect. + * For txtime-assist, it is implicitly assumed that the device's PHC is kept + * in sync with the specified clockid via a user space daemon such as phc2sys. + * For both software taprio and txtime-assist, the clockid is used for the + * hrtimer that advances the schedule and hence mandatory. + */ +static int taprio_parse_clockid(struct Qdisc *sch, struct nlattr **tb, + struct netlink_ext_ack *extack) +{ + struct taprio_sched *q = qdisc_priv(sch); + struct net_device *dev = qdisc_dev(sch); + int err = -EINVAL; + + if (FULL_OFFLOAD_IS_ENABLED(q->flags)) { + const struct ethtool_ops *ops = dev->ethtool_ops; + struct ethtool_ts_info info = { + .cmd = ETHTOOL_GET_TS_INFO, + .phc_index = -1, + }; + + if (tb[TCA_TAPRIO_ATTR_SCHED_CLOCKID]) { + NL_SET_ERR_MSG(extack, + "The 'clockid' cannot be specified for full offload"); + goto out; + } + + if (ops && ops->get_ts_info) + err = ops->get_ts_info(dev, &info); + + if (err || info.phc_index < 0) { + NL_SET_ERR_MSG(extack, + "Device does not have a PTP clock"); + err = -ENOTSUPP; + goto out; + } + } else if (tb[TCA_TAPRIO_ATTR_SCHED_CLOCKID]) { + int clockid = nla_get_s32(tb[TCA_TAPRIO_ATTR_SCHED_CLOCKID]); + enum tk_offsets tk_offset; + + /* 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)) { + NL_SET_ERR_MSG(extack, + "Changing the 'clockid' of a running schedule is not supported"); + err = -ENOTSUPP; + goto out; + } + + switch (clockid) { + case CLOCK_REALTIME: + tk_offset = TK_OFFS_REAL; + break; + case CLOCK_MONOTONIC: + tk_offset = TK_OFFS_MAX; + break; + case CLOCK_BOOTTIME: + tk_offset = TK_OFFS_BOOT; + break; + case CLOCK_TAI: + tk_offset = TK_OFFS_TAI; + break; + default: + NL_SET_ERR_MSG(extack, "Invalid 'clockid'"); + err = -EINVAL; + goto out; + } + /* This pairs with READ_ONCE() in taprio_mono_to_any */ + WRITE_ONCE(q->tk_offset, tk_offset); + + q->clockid = clockid; + } else { + NL_SET_ERR_MSG(extack, "Specifying a 'clockid' is mandatory"); + goto out; + } + + /* Everything went ok, return success. */ + err = 0; + +out: + return err; +} + +static int taprio_mqprio_cmp(const struct net_device *dev, + const struct tc_mqprio_qopt *mqprio) +{ + int i; + + if (!mqprio || mqprio->num_tc != dev->num_tc) + return -1; + + for (i = 0; i < mqprio->num_tc; i++) + if (dev->tc_to_txq[i].count != mqprio->count[i] || + dev->tc_to_txq[i].offset != mqprio->offset[i]) + return -1; + + for (i = 0; i <= TC_BITMASK; i++) + if (dev->prio_tc_map[i] != mqprio->prio_tc_map[i]) + return -1; + + return 0; +} + +/* The semantics of the 'flags' argument in relation to 'change()' + * requests, are interpreted following two rules (which are applied in + * this order): (1) an omitted 'flags' argument is interpreted as + * zero; (2) the 'flags' of a "running" taprio instance cannot be + * changed. + */ +static int taprio_new_flags(const struct nlattr *attr, u32 old, + struct netlink_ext_ack *extack) +{ + u32 new = 0; + + if (attr) + new = nla_get_u32(attr); + + if (old != TAPRIO_FLAGS_INVALID && old != new) { + NL_SET_ERR_MSG_MOD(extack, "Changing 'flags' of a running schedule is not supported"); + return -EOPNOTSUPP; + } + + if (!taprio_flags_valid(new)) { + NL_SET_ERR_MSG_MOD(extack, "Specified 'flags' are not valid"); + return -EINVAL; + } + + return new; +} + +static int taprio_change(struct Qdisc *sch, struct nlattr *opt, + struct netlink_ext_ack *extack) +{ + struct nlattr *tb[TCA_TAPRIO_ATTR_MAX + 1] = { }; + struct sched_gate_list *oper, *admin, *new_admin; + struct taprio_sched *q = qdisc_priv(sch); + struct net_device *dev = qdisc_dev(sch); + struct tc_mqprio_qopt *mqprio = NULL; + unsigned long flags; + ktime_t start; + int i, err; + + err = nla_parse_nested_deprecated(tb, TCA_TAPRIO_ATTR_MAX, opt, + taprio_policy, extack); + if (err < 0) + return err; + + if (tb[TCA_TAPRIO_ATTR_PRIOMAP]) + mqprio = nla_data(tb[TCA_TAPRIO_ATTR_PRIOMAP]); + + err = taprio_new_flags(tb[TCA_TAPRIO_ATTR_FLAGS], + q->flags, extack); + if (err < 0) + return err; + + q->flags = err; + + err = taprio_parse_mqprio_opt(dev, mqprio, extack, q->flags); + if (err < 0) + return err; + + new_admin = kzalloc(sizeof(*new_admin), GFP_KERNEL); + if (!new_admin) { + NL_SET_ERR_MSG(extack, "Not enough memory for a new schedule"); + return -ENOMEM; + } + INIT_LIST_HEAD(&new_admin->entries); + + rcu_read_lock(); + oper = rcu_dereference(q->oper_sched); + admin = rcu_dereference(q->admin_sched); + rcu_read_unlock(); + + /* no changes - no new mqprio settings */ + if (!taprio_mqprio_cmp(dev, mqprio)) + mqprio = NULL; + + if (mqprio && (oper || admin)) { + NL_SET_ERR_MSG(extack, "Changing the traffic mapping of a running schedule is not supported"); + err = -ENOTSUPP; + goto free_sched; + } + + err = parse_taprio_schedule(q, tb, new_admin, extack); + if (err < 0) + goto free_sched; + + if (new_admin->num_entries == 0) { + NL_SET_ERR_MSG(extack, "There should be at least one entry in the schedule"); + err = -EINVAL; + goto free_sched; + } + + err = taprio_parse_clockid(sch, tb, extack); + if (err < 0) + goto free_sched; + + taprio_set_picos_per_byte(dev, q); + + if (mqprio) { + err = netdev_set_num_tc(dev, mqprio->num_tc); + if (err) + goto free_sched; + 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; i++) + netdev_set_prio_tc_map(dev, i, + mqprio->prio_tc_map[i]); + } + + if (FULL_OFFLOAD_IS_ENABLED(q->flags)) + err = taprio_enable_offload(dev, q, new_admin, extack); + else + err = taprio_disable_offload(dev, q, extack); + if (err) + goto free_sched; + + /* Protects against enqueue()/dequeue() */ + spin_lock_bh(qdisc_lock(sch)); + + if (tb[TCA_TAPRIO_ATTR_TXTIME_DELAY]) { + if (!TXTIME_ASSIST_IS_ENABLED(q->flags)) { + NL_SET_ERR_MSG_MOD(extack, "txtime-delay can only be set when txtime-assist mode is enabled"); + err = -EINVAL; + goto unlock; + } + + q->txtime_delay = nla_get_u32(tb[TCA_TAPRIO_ATTR_TXTIME_DELAY]); + } + + if (!TXTIME_ASSIST_IS_ENABLED(q->flags) && + !FULL_OFFLOAD_IS_ENABLED(q->flags) && + !hrtimer_active(&q->advance_timer)) { + hrtimer_init(&q->advance_timer, q->clockid, HRTIMER_MODE_ABS); + q->advance_timer.function = advance_sched; + } + + if (FULL_OFFLOAD_IS_ENABLED(q->flags)) { + q->dequeue = taprio_dequeue_offload; + q->peek = taprio_peek_offload; + } else { + /* Be sure to always keep the function pointers + * in a consistent state. + */ + q->dequeue = taprio_dequeue_soft; + q->peek = taprio_peek_soft; + } + + err = taprio_get_start_time(sch, new_admin, &start); + if (err < 0) { + NL_SET_ERR_MSG(extack, "Internal error: failed get start time"); + goto unlock; + } + + setup_txtime(q, new_admin, start); + + if (TXTIME_ASSIST_IS_ENABLED(q->flags)) { + if (!oper) { + rcu_assign_pointer(q->oper_sched, new_admin); + err = 0; + new_admin = NULL; + goto unlock; + } + + rcu_assign_pointer(q->admin_sched, new_admin); + if (admin) + call_rcu(&admin->rcu, taprio_free_sched_cb); + } else { + setup_first_close_time(q, new_admin, start); + + /* Protects against advance_sched() */ + spin_lock_irqsave(&q->current_entry_lock, flags); + + taprio_start_sched(sch, start, new_admin); + + rcu_assign_pointer(q->admin_sched, new_admin); + if (admin) + call_rcu(&admin->rcu, taprio_free_sched_cb); + + spin_unlock_irqrestore(&q->current_entry_lock, flags); + + if (FULL_OFFLOAD_IS_ENABLED(q->flags)) + taprio_offload_config_changed(q); + } + + new_admin = NULL; + err = 0; + +unlock: + spin_unlock_bh(qdisc_lock(sch)); + +free_sched: + if (new_admin) + call_rcu(&new_admin->rcu, taprio_free_sched_cb); + + return err; +} + +static void taprio_reset(struct Qdisc *sch) +{ + struct taprio_sched *q = qdisc_priv(sch); + struct net_device *dev = qdisc_dev(sch); + int i; + + hrtimer_cancel(&q->advance_timer); + + if (q->qdiscs) { + for (i = 0; i < dev->num_tx_queues; i++) + if (q->qdiscs[i]) + qdisc_reset(q->qdiscs[i]); + } +} + +static void taprio_destroy(struct Qdisc *sch) +{ + struct taprio_sched *q = qdisc_priv(sch); + struct net_device *dev = qdisc_dev(sch); + unsigned int i; + + spin_lock(&taprio_list_lock); + list_del(&q->taprio_list); + spin_unlock(&taprio_list_lock); + + /* Note that taprio_reset() might not be called if an error + * happens in qdisc_create(), after taprio_init() has been called. + */ + hrtimer_cancel(&q->advance_timer); + qdisc_synchronize(sch); + + taprio_disable_offload(dev, q, NULL); + + if (q->qdiscs) { + for (i = 0; i < dev->num_tx_queues; i++) + qdisc_put(q->qdiscs[i]); + + kfree(q->qdiscs); + } + q->qdiscs = NULL; + + netdev_reset_tc(dev); + + if (q->oper_sched) + call_rcu(&q->oper_sched->rcu, taprio_free_sched_cb); + + if (q->admin_sched) + call_rcu(&q->admin_sched->rcu, taprio_free_sched_cb); +} + +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); + int i; + + spin_lock_init(&q->current_entry_lock); + + hrtimer_init(&q->advance_timer, CLOCK_TAI, HRTIMER_MODE_ABS); + q->advance_timer.function = advance_sched; + + q->dequeue = taprio_dequeue_soft; + q->peek = taprio_peek_soft; + + 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; + q->flags = TAPRIO_FLAGS_INVALID; + + spin_lock(&taprio_list_lock); + list_add(&q->taprio_list, &taprio_list); + spin_unlock(&taprio_list_lock); + + 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; + + 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; + } + + 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_noflag(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 dump_schedule(struct sk_buff *msg, + const struct sched_gate_list *root) +{ + struct nlattr *entry_list; + struct sched_entry *entry; + + if (nla_put_s64(msg, TCA_TAPRIO_ATTR_SCHED_BASE_TIME, + root->base_time, TCA_TAPRIO_PAD)) + return -1; + + if (nla_put_s64(msg, TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME, + root->cycle_time, TCA_TAPRIO_PAD)) + return -1; + + if (nla_put_s64(msg, TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME_EXTENSION, + root->cycle_time_extension, TCA_TAPRIO_PAD)) + return -1; + + entry_list = nla_nest_start_noflag(msg, + TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST); + if (!entry_list) + goto error_nest; + + list_for_each_entry(entry, &root->entries, list) { + if (dump_entry(msg, entry) < 0) + goto error_nest; + } + + nla_nest_end(msg, entry_list); + return 0; + +error_nest: + nla_nest_cancel(msg, entry_list); + 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 sched_gate_list *oper, *admin; + struct tc_mqprio_qopt opt = { 0 }; + struct nlattr *nest, *sched_nest; + unsigned int i; + + rcu_read_lock(); + oper = rcu_dereference(q->oper_sched); + admin = rcu_dereference(q->admin_sched); + + 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_noflag(skb, TCA_OPTIONS); + if (!nest) + goto start_error; + + if (nla_put(skb, TCA_TAPRIO_ATTR_PRIOMAP, sizeof(opt), &opt)) + goto options_error; + + if (!FULL_OFFLOAD_IS_ENABLED(q->flags) && + nla_put_s32(skb, TCA_TAPRIO_ATTR_SCHED_CLOCKID, q->clockid)) + goto options_error; + + if (q->flags && nla_put_u32(skb, TCA_TAPRIO_ATTR_FLAGS, q->flags)) + goto options_error; + + if (q->txtime_delay && + nla_put_u32(skb, TCA_TAPRIO_ATTR_TXTIME_DELAY, q->txtime_delay)) + goto options_error; + + if (oper && dump_schedule(skb, oper)) + goto options_error; + + if (!admin) + goto done; + + sched_nest = nla_nest_start_noflag(skb, TCA_TAPRIO_ATTR_ADMIN_SCHED); + if (!sched_nest) + goto options_error; + + if (dump_schedule(skb, admin)) + goto admin_error; + + nla_nest_end(skb, sched_nest); + +done: + rcu_read_unlock(); + + return nla_nest_end(skb, nest); + +admin_error: + nla_nest_cancel(skb, sched_nest); + +options_error: + nla_nest_cancel(skb, nest); + +start_error: + rcu_read_unlock(); + return -ENOSPC; +} + +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 || + qdisc_qstats_copy(d, sch) < 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, + .change = taprio_change, + .destroy = taprio_destroy, + .reset = taprio_reset, + .peek = taprio_peek, + .dequeue = taprio_dequeue, + .enqueue = taprio_enqueue, + .dump = taprio_dump, + .owner = THIS_MODULE, +}; + +static struct notifier_block taprio_device_notifier = { + .notifier_call = taprio_dev_notifier, +}; + +static int __init taprio_module_init(void) +{ + int err = register_netdevice_notifier(&taprio_device_notifier); + + if (err) + return err; + + return register_qdisc(&taprio_qdisc_ops); +} + +static void __exit taprio_module_exit(void) +{ + unregister_qdisc(&taprio_qdisc_ops); + unregister_netdevice_notifier(&taprio_device_notifier); +} + +module_init(taprio_module_init); +module_exit(taprio_module_exit); +MODULE_LICENSE("GPL"); |