From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- net/sched/sch_taprio.c | 2574 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 2574 insertions(+) create mode 100644 net/sched/sch_taprio.c (limited to 'net/sched/sch_taprio.c') diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c new file mode 100644 index 0000000000..1cb5e41c0e --- /dev/null +++ b/net/sched/sch_taprio.c @@ -0,0 +1,2574 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* net/sched/sch_taprio.c Time Aware Priority Scheduler + * + * Authors: Vinicius Costa Gomes + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define TAPRIO_STAT_NOT_SET (~0ULL) + +#include "sch_mqprio_lib.h" + +static LIST_HEAD(taprio_list); +static struct static_key_false taprio_have_broken_mqprio; +static struct static_key_false taprio_have_working_mqprio; + +#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 { + /* Durations between this GCL entry and the GCL entry where the + * respective traffic class gate closes + */ + u64 gate_duration[TC_MAX_QUEUE]; + atomic_t budget[TC_MAX_QUEUE]; + /* The qdisc makes some effort so that no packet leaves + * after this time + */ + ktime_t gate_close_time[TC_MAX_QUEUE]; + struct list_head list; + /* Used to calculate when to advance the schedule */ + ktime_t end_time; + ktime_t next_txtime; + int index; + u32 gate_mask; + u32 interval; + u8 command; +}; + +struct sched_gate_list { + /* Longest non-zero contiguous gate durations per traffic class, + * or 0 if a traffic class gate never opens during the schedule. + */ + u64 max_open_gate_duration[TC_MAX_QUEUE]; + u32 max_frm_len[TC_MAX_QUEUE]; /* for the fast path */ + u32 max_sdu[TC_MAX_QUEUE]; /* for dump */ + struct rcu_head rcu; + struct list_head entries; + size_t num_entries; + ktime_t cycle_end_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; + bool detected_mqprio; + bool broken_mqprio; + 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; + int cur_txq[TC_MAX_QUEUE]; + u32 max_sdu[TC_MAX_QUEUE]; /* save info from the user */ + u32 fp[TC_QOPT_MAX_QUEUE]; /* only for dump and offloading */ + u32 txtime_delay; +}; + +struct __tc_taprio_qopt_offload { + refcount_t users; + struct tc_taprio_qopt_offload offload; +}; + +static void taprio_calculate_gate_durations(struct taprio_sched *q, + struct sched_gate_list *sched) +{ + struct net_device *dev = qdisc_dev(q->root); + int num_tc = netdev_get_num_tc(dev); + struct sched_entry *entry, *cur; + int tc; + + list_for_each_entry(entry, &sched->entries, list) { + u32 gates_still_open = entry->gate_mask; + + /* For each traffic class, calculate each open gate duration, + * starting at this schedule entry and ending at the schedule + * entry containing a gate close event for that TC. + */ + cur = entry; + + do { + if (!gates_still_open) + break; + + for (tc = 0; tc < num_tc; tc++) { + if (!(gates_still_open & BIT(tc))) + continue; + + if (cur->gate_mask & BIT(tc)) + entry->gate_duration[tc] += cur->interval; + else + gates_still_open &= ~BIT(tc); + } + + cur = list_next_entry_circular(cur, &sched->entries, list); + } while (cur != entry); + + /* Keep track of the maximum gate duration for each traffic + * class, taking care to not confuse a traffic class which is + * temporarily closed with one that is always closed. + */ + for (tc = 0; tc < num_tc; tc++) + if (entry->gate_duration[tc] && + sched->max_open_gate_duration[tc] < entry->gate_duration[tc]) + sched->max_open_gate_duration[tc] = entry->gate_duration[tc]; + } +} + +static bool taprio_entry_allows_tx(ktime_t skb_end_time, + struct sched_entry *entry, int tc) +{ + return ktime_before(skb_end_time, entry->gate_close_time[tc]); +} + +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; + + 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), PSEC_PER_NSEC); +} + +static int duration_to_length(struct taprio_sched *q, u64 duration) +{ + return div_u64(duration * PSEC_PER_NSEC, atomic64_read(&q->picos_per_byte)); +} + +/* Sets sched->max_sdu[] and sched->max_frm_len[] to the minimum between the + * q->max_sdu[] requested by the user and the max_sdu dynamically determined by + * the maximum open gate durations at the given link speed. + */ +static void taprio_update_queue_max_sdu(struct taprio_sched *q, + struct sched_gate_list *sched, + struct qdisc_size_table *stab) +{ + struct net_device *dev = qdisc_dev(q->root); + int num_tc = netdev_get_num_tc(dev); + u32 max_sdu_from_user; + u32 max_sdu_dynamic; + u32 max_sdu; + int tc; + + for (tc = 0; tc < num_tc; tc++) { + max_sdu_from_user = q->max_sdu[tc] ?: U32_MAX; + + /* TC gate never closes => keep the queueMaxSDU + * selected by the user + */ + if (sched->max_open_gate_duration[tc] == sched->cycle_time) { + max_sdu_dynamic = U32_MAX; + } else { + u32 max_frm_len; + + max_frm_len = duration_to_length(q, sched->max_open_gate_duration[tc]); + /* Compensate for L1 overhead from size table, + * but don't let the frame size go negative + */ + if (stab) { + max_frm_len -= stab->szopts.overhead; + max_frm_len = max_t(int, max_frm_len, + dev->hard_header_len + 1); + } + max_sdu_dynamic = max_frm_len - dev->hard_header_len; + if (max_sdu_dynamic > dev->max_mtu) + max_sdu_dynamic = U32_MAX; + } + + max_sdu = min(max_sdu_dynamic, max_sdu_from_user); + + if (max_sdu != U32_MAX) { + sched->max_frm_len[tc] = max_sdu + dev->hard_header_len; + sched->max_sdu[tc] = max_sdu; + } else { + sched->max_frm_len[tc] = U32_MAX; /* never oversized */ + sched->max_sdu[tc] = 0; + } + } +} + +/* 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 = true; + 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 = false; + + 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 = true; + 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; +} + +/* Devices with full offload are expected to honor this in hardware */ +static bool taprio_skb_exceeds_queue_max_sdu(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 *sched; + int prio = skb->priority; + bool exceeds = false; + u8 tc; + + tc = netdev_get_prio_tc_map(dev, prio); + + rcu_read_lock(); + sched = rcu_dereference(q->oper_sched); + if (sched && skb->len > sched->max_frm_len[tc]) + exceeds = true; + rcu_read_unlock(); + + return exceeds; +} + +static int taprio_enqueue_one(struct sk_buff *skb, struct Qdisc *sch, + struct Qdisc *child, struct sk_buff **to_free) +{ + struct taprio_sched *q = qdisc_priv(sch); + + /* 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 int taprio_enqueue_segmented(struct sk_buff *skb, struct Qdisc *sch, + struct Qdisc *child, + struct sk_buff **to_free) +{ + unsigned int slen = 0, numsegs = 0, len = qdisc_pkt_len(skb); + netdev_features_t features = netif_skb_features(skb); + struct sk_buff *segs, *nskb; + int ret; + + segs = skb_gso_segment(skb, features & ~NETIF_F_GSO_MASK); + if (IS_ERR_OR_NULL(segs)) + return qdisc_drop(skb, sch, to_free); + + skb_list_walk_safe(segs, segs, nskb) { + skb_mark_not_on_list(segs); + qdisc_skb_cb(segs)->pkt_len = segs->len; + slen += segs->len; + + /* FIXME: we should be segmenting to a smaller size + * rather than dropping these + */ + if (taprio_skb_exceeds_queue_max_sdu(sch, segs)) + ret = qdisc_drop(segs, sch, to_free); + else + ret = taprio_enqueue_one(segs, sch, child, to_free); + + if (ret != NET_XMIT_SUCCESS) { + if (net_xmit_drop_count(ret)) + qdisc_qstats_drop(sch); + } else { + numsegs++; + } + } + + if (numsegs > 1) + qdisc_tree_reduce_backlog(sch, 1 - numsegs, len - slen); + consume_skb(skb); + + return numsegs > 0 ? NET_XMIT_SUCCESS : NET_XMIT_DROP; +} + +/* Will not be called in the full offload case, since the TX queues are + * attached to the Qdisc created using qdisc_create_dflt() + */ +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); + + if (taprio_skb_exceeds_queue_max_sdu(sch, skb)) { + /* Large packets might not be transmitted when the transmission + * duration exceeds any configured interval. Therefore, segment + * the skb into smaller chunks. Drivers with full offload are + * expected to handle this in hardware. + */ + if (skb_is_gso(skb)) + return taprio_enqueue_segmented(skb, sch, child, + to_free); + + return qdisc_drop(skb, sch, to_free); + } + + return taprio_enqueue_one(skb, sch, child, to_free); +} + +static struct sk_buff *taprio_peek(struct Qdisc *sch) +{ + WARN_ONCE(1, "taprio only supports operating as root qdisc, peek() not implemented"); + return NULL; +} + +static void taprio_set_budgets(struct taprio_sched *q, + struct sched_gate_list *sched, + struct sched_entry *entry) +{ + struct net_device *dev = qdisc_dev(q->root); + int num_tc = netdev_get_num_tc(dev); + int tc, budget; + + for (tc = 0; tc < num_tc; tc++) { + /* Traffic classes which never close have infinite budget */ + if (entry->gate_duration[tc] == sched->cycle_time) + budget = INT_MAX; + else + budget = div64_u64((u64)entry->gate_duration[tc] * PSEC_PER_NSEC, + atomic64_read(&q->picos_per_byte)); + + atomic_set(&entry->budget[tc], budget); + } +} + +/* When an skb is sent, it consumes from the budget of all traffic classes */ +static int taprio_update_budgets(struct sched_entry *entry, size_t len, + int tc_consumed, int num_tc) +{ + int tc, budget, new_budget = 0; + + for (tc = 0; tc < num_tc; tc++) { + budget = atomic_read(&entry->budget[tc]); + /* Don't consume from infinite budget */ + if (budget == INT_MAX) { + if (tc == tc_consumed) + new_budget = budget; + continue; + } + + if (tc == tc_consumed) + new_budget = atomic_sub_return(len, &entry->budget[tc]); + else + atomic_sub(len, &entry->budget[tc]); + } + + return new_budget; +} + +static struct sk_buff *taprio_dequeue_from_txq(struct Qdisc *sch, int txq, + struct sched_entry *entry, + u32 gate_mask) +{ + struct taprio_sched *q = qdisc_priv(sch); + struct net_device *dev = qdisc_dev(sch); + struct Qdisc *child = q->qdiscs[txq]; + int num_tc = netdev_get_num_tc(dev); + struct sk_buff *skb; + ktime_t guard; + int prio; + int len; + u8 tc; + + if (unlikely(!child)) + return NULL; + + if (TXTIME_ASSIST_IS_ENABLED(q->flags)) + goto skip_peek_checks; + + skb = child->ops->peek(child); + if (!skb) + return NULL; + + prio = skb->priority; + tc = netdev_get_prio_tc_map(dev, prio); + + if (!(gate_mask & BIT(tc))) + return NULL; + + 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 && + !taprio_entry_allows_tx(guard, entry, tc)) + return NULL; + + /* ... and no budget. */ + if (gate_mask != TAPRIO_ALL_GATES_OPEN && + taprio_update_budgets(entry, len, tc, num_tc) < 0) + return NULL; + +skip_peek_checks: + 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; +} + +static void taprio_next_tc_txq(struct net_device *dev, int tc, int *txq) +{ + int offset = dev->tc_to_txq[tc].offset; + int count = dev->tc_to_txq[tc].count; + + (*txq)++; + if (*txq == offset + count) + *txq = offset; +} + +/* Prioritize higher traffic classes, and select among TXQs belonging to the + * same TC using round robin + */ +static struct sk_buff *taprio_dequeue_tc_priority(struct Qdisc *sch, + struct sched_entry *entry, + u32 gate_mask) +{ + struct taprio_sched *q = qdisc_priv(sch); + struct net_device *dev = qdisc_dev(sch); + int num_tc = netdev_get_num_tc(dev); + struct sk_buff *skb; + int tc; + + for (tc = num_tc - 1; tc >= 0; tc--) { + int first_txq = q->cur_txq[tc]; + + if (!(gate_mask & BIT(tc))) + continue; + + do { + skb = taprio_dequeue_from_txq(sch, q->cur_txq[tc], + entry, gate_mask); + + taprio_next_tc_txq(dev, tc, &q->cur_txq[tc]); + + if (q->cur_txq[tc] >= dev->num_tx_queues) + q->cur_txq[tc] = first_txq; + + if (skb) + return skb; + } while (q->cur_txq[tc] != first_txq); + } + + return NULL; +} + +/* Broken way of prioritizing smaller TXQ indices and ignoring the traffic + * class other than to determine whether the gate is open or not + */ +static struct sk_buff *taprio_dequeue_txq_priority(struct Qdisc *sch, + struct sched_entry *entry, + u32 gate_mask) +{ + struct net_device *dev = qdisc_dev(sch); + struct sk_buff *skb; + int i; + + for (i = 0; i < dev->num_tx_queues; i++) { + skb = taprio_dequeue_from_txq(sch, i, entry, gate_mask); + if (skb) + return skb; + } + + return NULL; +} + +/* Will not be called in the full offload case, since the TX queues are + * attached to the Qdisc created using qdisc_create_dflt() + */ +static struct sk_buff *taprio_dequeue(struct Qdisc *sch) +{ + struct taprio_sched *q = qdisc_priv(sch); + struct sk_buff *skb = NULL; + struct sched_entry *entry; + u32 gate_mask; + + 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 + * "AdminGateStates" + */ + gate_mask = entry ? entry->gate_mask : TAPRIO_ALL_GATES_OPEN; + if (!gate_mask) + goto done; + + if (static_branch_unlikely(&taprio_have_broken_mqprio) && + !static_branch_likely(&taprio_have_working_mqprio)) { + /* Single NIC kind which is broken */ + skb = taprio_dequeue_txq_priority(sch, entry, gate_mask); + } else if (static_branch_likely(&taprio_have_working_mqprio) && + !static_branch_unlikely(&taprio_have_broken_mqprio)) { + /* Single NIC kind which prioritizes properly */ + skb = taprio_dequeue_tc_priority(sch, entry, gate_mask); + } else { + /* Mixed NIC kinds present in system, need dynamic testing */ + if (q->broken_mqprio) + skb = taprio_dequeue_txq_priority(sch, entry, gate_mask); + else + skb = taprio_dequeue_tc_priority(sch, entry, gate_mask); + } + +done: + rcu_read_unlock(); + + return skb; +} + +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->end_time, oper->cycle_end_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 end_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 end_time would fall after + * the next schedule base_time. + */ + if (ktime_compare(next_base_time, end_time) <= 0) + return true; + + /* This is the cycle_time_extension case, if the end_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(end_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 net_device *dev = qdisc_dev(q->root); + struct sched_gate_list *oper, *admin; + int num_tc = netdev_get_num_tc(dev); + struct sched_entry *entry, *next; + struct Qdisc *sch = q->root; + ktime_t end_time; + int tc; + + 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->end_time == oper->base_time)) { + next = list_first_entry(&oper->entries, struct sched_entry, + list); + end_time = next->end_time; + goto first_run; + } + + if (should_restart_cycle(oper, entry)) { + next = list_first_entry(&oper->entries, struct sched_entry, + list); + oper->cycle_end_time = ktime_add_ns(oper->cycle_end_time, + oper->cycle_time); + } else { + next = list_next_entry(entry, list); + } + + end_time = ktime_add_ns(entry->end_time, next->interval); + end_time = min_t(ktime_t, end_time, oper->cycle_end_time); + + for (tc = 0; tc < num_tc; tc++) { + if (next->gate_duration[tc] == oper->cycle_time) + next->gate_close_time[tc] = KTIME_MAX; + else + next->gate_close_time[tc] = ktime_add_ns(entry->end_time, + next->gate_duration[tc]); + } + + if (should_change_schedules(admin, oper, end_time)) { + /* Set things so the next time this runs, the new + * schedule runs. + */ + end_time = sched_base_time(admin); + switch_schedules(q, &admin, &oper); + } + + next->end_time = end_time; + taprio_set_budgets(q, oper, next); + +first_run: + rcu_assign_pointer(q->current_entry, next); + spin_unlock(&q->current_entry_lock); + + hrtimer_set_expires(&q->advance_timer, end_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_tc_policy[TCA_TAPRIO_TC_ENTRY_MAX + 1] = { + [TCA_TAPRIO_TC_ENTRY_INDEX] = { .type = NLA_U32 }, + [TCA_TAPRIO_TC_ENTRY_MAX_SDU] = { .type = NLA_U32 }, + [TCA_TAPRIO_TC_ENTRY_FP] = NLA_POLICY_RANGE(NLA_U32, + TC_FP_EXPRESS, + TC_FP_PREEMPTIBLE), +}; + +static struct netlink_range_validation_signed taprio_cycle_time_range = { + .min = 0, + .max = INT_MAX, +}; + +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] = + NLA_POLICY_FULL_RANGE_SIGNED(NLA_S64, &taprio_cycle_time_range), + [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 }, + [TCA_TAPRIO_ATTR_TC_ENTRY] = { .type = NLA_NESTED }, +}; + +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; + } + + if (cycle < 0 || cycle > INT_MAX) { + NL_SET_ERR_MSG(extack, "'cycle_time' is too big"); + return -EINVAL; + } + + new->cycle_time = cycle; + } + + taprio_calculate_gate_durations(q, new); + + 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) +{ + bool allow_overlapping_txqs = TXTIME_ASSIST_IS_ENABLED(taprio_flags); + + 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; + + /* 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; + } + + /* For some reason, in txtime-assist mode, we allow TXQ ranges for + * different TCs to overlap, and just validate the TXQ ranges. + */ + return mqprio_validate_qopt(dev, qopt, true, allow_overlapping_txqs, + extack); +} + +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_end_time(struct taprio_sched *q, + struct sched_gate_list *sched, ktime_t base) +{ + struct net_device *dev = qdisc_dev(q->root); + int num_tc = netdev_get_num_tc(dev); + struct sched_entry *first; + ktime_t cycle; + int tc; + + first = list_first_entry(&sched->entries, + struct sched_entry, list); + + cycle = sched->cycle_time; + + /* FIXME: find a better place to do this */ + sched->cycle_end_time = ktime_add_ns(base, cycle); + + first->end_time = ktime_add_ns(base, first->interval); + taprio_set_budgets(q, sched, first); + + for (tc = 0; tc < num_tc; tc++) { + if (first->gate_duration[tc] == sched->cycle_time) + first->gate_close_time[tc] = KTIME_MAX; + else + first->gate_close_time[tc] = ktime_add_ns(base, first->gate_duration[tc]); + } + + 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 sched_gate_list *oper, *admin; + struct qdisc_size_table *stab; + struct taprio_sched *q; + + ASSERT_RTNL(); + + if (event != NETDEV_UP && event != NETDEV_CHANGE) + return NOTIFY_DONE; + + list_for_each_entry(q, &taprio_list, taprio_list) { + if (dev != qdisc_dev(q->root)) + continue; + + taprio_set_picos_per_byte(dev, q); + + stab = rtnl_dereference(q->root->stab); + + oper = rtnl_dereference(q->oper_sched); + if (oper) + taprio_update_queue_max_sdu(q, oper, stab); + + admin = rtnl_dereference(q->admin_sched); + if (admin) + taprio_update_queue_max_sdu(q, admin, stab); + + break; + } + + return NOTIFY_DONE; +} + +static void setup_txtime(struct taprio_sched *q, + struct sched_gate_list *sched, ktime_t base) +{ + struct sched_entry *entry; + u64 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; + + oper = rtnl_dereference(q->oper_sched); + admin = rtnl_dereference(q->admin_sched); + + switch_schedules(q, &admin, &oper); +} + +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, + const struct tc_taprio_caps *caps) +{ + 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; + if (caps->gate_mask_per_txq) + e->gate_mask = tc_map_to_queue_mask(dev, + entry->gate_mask); + else + e->gate_mask = entry->gate_mask; + + i++; + } + + offload->num_entries = i; +} + +static void taprio_detect_broken_mqprio(struct taprio_sched *q) +{ + struct net_device *dev = qdisc_dev(q->root); + struct tc_taprio_caps caps; + + qdisc_offload_query_caps(dev, TC_SETUP_QDISC_TAPRIO, + &caps, sizeof(caps)); + + q->broken_mqprio = caps.broken_mqprio; + if (q->broken_mqprio) + static_branch_inc(&taprio_have_broken_mqprio); + else + static_branch_inc(&taprio_have_working_mqprio); + + q->detected_mqprio = true; +} + +static void taprio_cleanup_broken_mqprio(struct taprio_sched *q) +{ + if (!q->detected_mqprio) + return; + + if (q->broken_mqprio) + static_branch_dec(&taprio_have_broken_mqprio); + else + static_branch_dec(&taprio_have_working_mqprio); +} + +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; + struct tc_taprio_caps caps; + int tc, err = 0; + + if (!ops->ndo_setup_tc) { + NL_SET_ERR_MSG(extack, + "Device does not support taprio offload"); + return -EOPNOTSUPP; + } + + qdisc_offload_query_caps(dev, TC_SETUP_QDISC_TAPRIO, + &caps, sizeof(caps)); + + if (!caps.supports_queue_max_sdu) { + for (tc = 0; tc < TC_MAX_QUEUE; tc++) { + if (q->max_sdu[tc]) { + NL_SET_ERR_MSG_MOD(extack, + "Device does not handle queueMaxSDU"); + 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->cmd = TAPRIO_CMD_REPLACE; + offload->extack = extack; + mqprio_qopt_reconstruct(dev, &offload->mqprio.qopt); + offload->mqprio.extack = extack; + taprio_sched_to_offload(dev, sched, offload, &caps); + mqprio_fp_to_offload(q->fp, &offload->mqprio); + + for (tc = 0; tc < TC_MAX_QUEUE; tc++) + offload->max_sdu[tc] = q->max_sdu[tc]; + + err = ops->ndo_setup_tc(dev, TC_SETUP_QDISC_TAPRIO, offload); + if (err < 0) { + NL_SET_ERR_MSG_WEAK(extack, + "Device failed to setup taprio offload"); + goto done; + } + + q->offloaded = true; + +done: + /* The offload structure may linger around via a reference taken by the + * device driver, so clear up the netlink extack pointer so that the + * driver isn't tempted to dereference data which stopped being valid + */ + offload->extack = NULL; + offload->mqprio.extack = NULL; + 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->cmd = TAPRIO_CMD_DESTROY; + + 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_parse_tc_entry(struct Qdisc *sch, + struct nlattr *opt, + u32 max_sdu[TC_QOPT_MAX_QUEUE], + u32 fp[TC_QOPT_MAX_QUEUE], + unsigned long *seen_tcs, + struct netlink_ext_ack *extack) +{ + struct nlattr *tb[TCA_TAPRIO_TC_ENTRY_MAX + 1] = { }; + struct net_device *dev = qdisc_dev(sch); + int err, tc; + u32 val; + + err = nla_parse_nested(tb, TCA_TAPRIO_TC_ENTRY_MAX, opt, + taprio_tc_policy, extack); + if (err < 0) + return err; + + if (!tb[TCA_TAPRIO_TC_ENTRY_INDEX]) { + NL_SET_ERR_MSG_MOD(extack, "TC entry index missing"); + return -EINVAL; + } + + tc = nla_get_u32(tb[TCA_TAPRIO_TC_ENTRY_INDEX]); + if (tc >= TC_QOPT_MAX_QUEUE) { + NL_SET_ERR_MSG_MOD(extack, "TC entry index out of range"); + return -ERANGE; + } + + if (*seen_tcs & BIT(tc)) { + NL_SET_ERR_MSG_MOD(extack, "Duplicate TC entry"); + return -EINVAL; + } + + *seen_tcs |= BIT(tc); + + if (tb[TCA_TAPRIO_TC_ENTRY_MAX_SDU]) { + val = nla_get_u32(tb[TCA_TAPRIO_TC_ENTRY_MAX_SDU]); + if (val > dev->max_mtu) { + NL_SET_ERR_MSG_MOD(extack, "TC max SDU exceeds device max MTU"); + return -ERANGE; + } + + max_sdu[tc] = val; + } + + if (tb[TCA_TAPRIO_TC_ENTRY_FP]) + fp[tc] = nla_get_u32(tb[TCA_TAPRIO_TC_ENTRY_FP]); + + return 0; +} + +static int taprio_parse_tc_entries(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); + u32 max_sdu[TC_QOPT_MAX_QUEUE]; + bool have_preemption = false; + unsigned long seen_tcs = 0; + u32 fp[TC_QOPT_MAX_QUEUE]; + struct nlattr *n; + int tc, rem; + int err = 0; + + for (tc = 0; tc < TC_QOPT_MAX_QUEUE; tc++) { + max_sdu[tc] = q->max_sdu[tc]; + fp[tc] = q->fp[tc]; + } + + nla_for_each_nested(n, opt, rem) { + if (nla_type(n) != TCA_TAPRIO_ATTR_TC_ENTRY) + continue; + + err = taprio_parse_tc_entry(sch, n, max_sdu, fp, &seen_tcs, + extack); + if (err) + return err; + } + + for (tc = 0; tc < TC_QOPT_MAX_QUEUE; tc++) { + q->max_sdu[tc] = max_sdu[tc]; + q->fp[tc] = fp[tc]; + if (fp[tc] != TC_FP_EXPRESS) + have_preemption = true; + } + + if (have_preemption) { + if (!FULL_OFFLOAD_IS_ENABLED(q->flags)) { + NL_SET_ERR_MSG(extack, + "Preemption only supported with full offload"); + return -EOPNOTSUPP; + } + + if (!ethtool_dev_mm_supported(dev)) { + NL_SET_ERR_MSG(extack, + "Device does not support preemption"); + return -EOPNOTSUPP; + } + } + + 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 qdisc_size_table *stab = rtnl_dereference(sch->stab); + 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; + + err = taprio_parse_tc_entries(sch, opt, extack); + if (err) + 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); + + oper = rtnl_dereference(q->oper_sched); + admin = rtnl_dereference(q->admin_sched); + + /* 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; + } + + 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]); + q->cur_txq[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]); + } + + 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); + taprio_update_queue_max_sdu(q, new_admin, stab); + + 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; + } + + 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_end_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; + + if (!stab) + NL_SET_ERR_MSG_MOD(extack, + "Size table not specified, frame length estimations may be inaccurate"); + +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); + struct sched_gate_list *oper, *admin; + unsigned int i; + + list_del(&q->taprio_list); + + /* 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); + + oper = rtnl_dereference(q->oper_sched); + admin = rtnl_dereference(q->admin_sched); + + if (oper) + call_rcu(&oper->rcu, taprio_free_sched_cb); + + if (admin) + call_rcu(&admin->rcu, taprio_free_sched_cb); + + taprio_cleanup_broken_mqprio(q); +} + +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, tc; + + spin_lock_init(&q->current_entry_lock); + + hrtimer_init(&q->advance_timer, CLOCK_TAI, HRTIMER_MODE_ABS); + q->advance_timer.function = advance_sched; + + 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; + + list_add(&q->taprio_list, &taprio_list); + + if (sch->parent != TC_H_ROOT) { + NL_SET_ERR_MSG_MOD(extack, "Can only be attached as root qdisc"); + return -EOPNOTSUPP; + } + + if (!netif_is_multiqueue(dev)) { + NL_SET_ERR_MSG_MOD(extack, "Multi-queue device is required"); + return -EOPNOTSUPP; + } + + 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; + } + + for (tc = 0; tc < TC_QOPT_MAX_QUEUE; tc++) + q->fp[tc] = TC_FP_EXPRESS; + + taprio_detect_broken_mqprio(q); + + return taprio_change(sch, opt, extack); +} + +static void taprio_attach(struct Qdisc *sch) +{ + struct taprio_sched *q = qdisc_priv(sch); + struct net_device *dev = qdisc_dev(sch); + unsigned int ntx; + + /* Attach underlying qdisc */ + for (ntx = 0; ntx < dev->num_tx_queues; ntx++) { + struct netdev_queue *dev_queue = netdev_get_tx_queue(dev, ntx); + struct Qdisc *old, *dev_queue_qdisc; + + if (FULL_OFFLOAD_IS_ENABLED(q->flags)) { + struct Qdisc *qdisc = q->qdiscs[ntx]; + + /* In offload mode, the root taprio qdisc is bypassed + * and the netdev TX queues see the children directly + */ + qdisc->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT; + dev_queue_qdisc = qdisc; + } else { + /* In software mode, attach the root taprio qdisc + * to all netdev TX queues, so that dev_qdisc_enqueue() + * goes through taprio_enqueue(). + */ + dev_queue_qdisc = sch; + } + old = dev_graft_qdisc(dev_queue, dev_queue_qdisc); + /* The qdisc's refcount requires to be elevated once + * for each netdev TX queue it is grafted onto + */ + qdisc_refcount_inc(dev_queue_qdisc); + if (old) + qdisc_put(old); + } +} + +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); + + /* In offload mode, the child Qdisc is directly attached to the netdev + * TX queue, and thus, we need to keep its refcount elevated in order + * to counteract qdisc_graft()'s call to qdisc_put() once per TX queue. + * However, save the reference to the new qdisc in the private array in + * both software and offload cases, to have an up-to-date reference to + * our children. + */ + *old = q->qdiscs[cl - 1]; + if (FULL_OFFLOAD_IS_ENABLED(q->flags)) { + WARN_ON_ONCE(dev_graft_qdisc(dev_queue, new) != *old); + if (new) + qdisc_refcount_inc(new); + if (*old) + qdisc_put(*old); + } + + 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_tc_entries(struct sk_buff *skb, + struct taprio_sched *q, + struct sched_gate_list *sched) +{ + struct nlattr *n; + int tc; + + for (tc = 0; tc < TC_MAX_QUEUE; tc++) { + n = nla_nest_start(skb, TCA_TAPRIO_ATTR_TC_ENTRY); + if (!n) + return -EMSGSIZE; + + if (nla_put_u32(skb, TCA_TAPRIO_TC_ENTRY_INDEX, tc)) + goto nla_put_failure; + + if (nla_put_u32(skb, TCA_TAPRIO_TC_ENTRY_MAX_SDU, + sched->max_sdu[tc])) + goto nla_put_failure; + + if (nla_put_u32(skb, TCA_TAPRIO_TC_ENTRY_FP, q->fp[tc])) + goto nla_put_failure; + + nla_nest_end(skb, n); + } + + return 0; + +nla_put_failure: + nla_nest_cancel(skb, n); + return -EMSGSIZE; +} + +static int taprio_put_stat(struct sk_buff *skb, u64 val, u16 attrtype) +{ + if (val == TAPRIO_STAT_NOT_SET) + return 0; + if (nla_put_u64_64bit(skb, attrtype, val, TCA_TAPRIO_OFFLOAD_STATS_PAD)) + return -EMSGSIZE; + return 0; +} + +static int taprio_dump_xstats(struct Qdisc *sch, struct gnet_dump *d, + struct tc_taprio_qopt_offload *offload, + struct tc_taprio_qopt_stats *stats) +{ + struct net_device *dev = qdisc_dev(sch); + const struct net_device_ops *ops; + struct sk_buff *skb = d->skb; + struct nlattr *xstats; + int err; + + ops = qdisc_dev(sch)->netdev_ops; + + /* FIXME I could use qdisc_offload_dump_helper(), but that messes + * with sch->flags depending on whether the device reports taprio + * stats, and I'm not sure whether that's a good idea, considering + * that stats are optional to the offload itself + */ + if (!ops->ndo_setup_tc) + return 0; + + memset(stats, 0xff, sizeof(*stats)); + + err = ops->ndo_setup_tc(dev, TC_SETUP_QDISC_TAPRIO, offload); + if (err == -EOPNOTSUPP) + return 0; + if (err) + return err; + + xstats = nla_nest_start(skb, TCA_STATS_APP); + if (!xstats) + goto err; + + if (taprio_put_stat(skb, stats->window_drops, + TCA_TAPRIO_OFFLOAD_STATS_WINDOW_DROPS) || + taprio_put_stat(skb, stats->tx_overruns, + TCA_TAPRIO_OFFLOAD_STATS_TX_OVERRUNS)) + goto err_cancel; + + nla_nest_end(skb, xstats); + + return 0; + +err_cancel: + nla_nest_cancel(skb, xstats); +err: + return -EMSGSIZE; +} + +static int taprio_dump_stats(struct Qdisc *sch, struct gnet_dump *d) +{ + struct tc_taprio_qopt_offload offload = { + .cmd = TAPRIO_CMD_STATS, + }; + + return taprio_dump_xstats(sch, d, &offload, &offload.stats); +} + +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; + + oper = rtnl_dereference(q->oper_sched); + admin = rtnl_dereference(q->admin_sched); + + mqprio_qopt_reconstruct(dev, &opt); + + 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 && taprio_dump_tc_entries(skb, q, oper)) + 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: + return nla_nest_end(skb, nest); + +admin_error: + nla_nest_cancel(skb, sched_nest); + +options_error: + nla_nest_cancel(skb, nest); + +start_error: + return -ENOSPC; +} + +static struct Qdisc *taprio_leaf(struct Qdisc *sch, unsigned long cl) +{ + struct taprio_sched *q = qdisc_priv(sch); + struct net_device *dev = qdisc_dev(sch); + unsigned int ntx = cl - 1; + + if (ntx >= dev->num_tx_queues) + return NULL; + + return q->qdiscs[ntx]; +} + +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 Qdisc *child = taprio_leaf(sch, cl); + + tcm->tcm_parent = TC_H_ROOT; + tcm->tcm_handle |= TC_H_MIN(cl); + tcm->tcm_info = child->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 Qdisc *child = taprio_leaf(sch, cl); + struct tc_taprio_qopt_offload offload = { + .cmd = TAPRIO_CMD_QUEUE_STATS, + .queue_stats = { + .queue = cl - 1, + }, + }; + + if (gnet_stats_copy_basic(d, NULL, &child->bstats, true) < 0 || + qdisc_qstats_copy(d, child) < 0) + return -1; + + return taprio_dump_xstats(sch, d, &offload, &offload.queue_stats.stats); +} + +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 (!tc_qdisc_stats_dump(sch, ntx + 1, arg)) + break; + } +} + +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, + .attach = taprio_attach, + .peek = taprio_peek, + .dequeue = taprio_dequeue, + .enqueue = taprio_enqueue, + .dump = taprio_dump, + .dump_stats = taprio_dump_stats, + .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"); -- cgit v1.2.3