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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /net/sched/sch_taprio.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'net/sched/sch_taprio.c')
-rw-r--r--net/sched/sch_taprio.c2574
1 files changed, 2574 insertions, 0 deletions
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 <vinicius.gomes@intel.com>
+ *
+ */
+
+#include <linux/ethtool.h>
+#include <linux/ethtool_netlink.h>
+#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 <linux/time.h>
+#include <net/gso.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>
+
+#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");