1 // SPDX-License-Identifier: GPL-2.0
2
3 /* net/sched/sch_taprio.c Time Aware Priority Scheduler
4 *
5 * Authors: Vinicius Costa Gomes <vinicius.gomes@intel.com>
6 *
7 */
8
9 #include <linux/ethtool.h>
10 #include <linux/ethtool_netlink.h>
11 #include <linux/types.h>
12 #include <linux/slab.h>
13 #include <linux/kernel.h>
14 #include <linux/string.h>
15 #include <linux/list.h>
16 #include <linux/errno.h>
17 #include <linux/skbuff.h>
18 #include <linux/math64.h>
19 #include <linux/module.h>
20 #include <linux/spinlock.h>
21 #include <linux/rcupdate.h>
22 #include <linux/time.h>
23 #include <net/gso.h>
24 #include <net/netlink.h>
25 #include <net/pkt_sched.h>
26 #include <net/pkt_cls.h>
27 #include <net/sch_generic.h>
28 #include <net/sock.h>
29 #include <net/tcp.h>
30
31 #define TAPRIO_STAT_NOT_SET (~0ULL)
32
33 #include "sch_mqprio_lib.h"
34
35 static LIST_HEAD(taprio_list);
36 static struct static_key_false taprio_have_broken_mqprio;
37 static struct static_key_false taprio_have_working_mqprio;
38
39 #define TAPRIO_ALL_GATES_OPEN -1
40
41 #define TXTIME_ASSIST_IS_ENABLED(flags) ((flags) & TCA_TAPRIO_ATTR_FLAG_TXTIME_ASSIST)
42 #define FULL_OFFLOAD_IS_ENABLED(flags) ((flags) & TCA_TAPRIO_ATTR_FLAG_FULL_OFFLOAD)
43 #define TAPRIO_FLAGS_INVALID U32_MAX
44
45 struct sched_entry {
46 /* Durations between this GCL entry and the GCL entry where the
47 * respective traffic class gate closes
48 */
49 u64 gate_duration[TC_MAX_QUEUE];
50 atomic_t budget[TC_MAX_QUEUE];
51 /* The qdisc makes some effort so that no packet leaves
52 * after this time
53 */
54 ktime_t gate_close_time[TC_MAX_QUEUE];
55 struct list_head list;
56 /* Used to calculate when to advance the schedule */
57 ktime_t end_time;
58 ktime_t next_txtime;
59 int index;
60 u32 gate_mask;
61 u32 interval;
62 u8 command;
63 };
64
65 struct sched_gate_list {
66 /* Longest non-zero contiguous gate durations per traffic class,
67 * or 0 if a traffic class gate never opens during the schedule.
68 */
69 u64 max_open_gate_duration[TC_MAX_QUEUE];
70 u32 max_frm_len[TC_MAX_QUEUE]; /* for the fast path */
71 u32 max_sdu[TC_MAX_QUEUE]; /* for dump */
72 struct rcu_head rcu;
73 struct list_head entries;
74 size_t num_entries;
75 ktime_t cycle_end_time;
76 s64 cycle_time;
77 s64 cycle_time_extension;
78 s64 base_time;
79 };
80
81 struct taprio_sched {
82 struct Qdisc **qdiscs;
83 struct Qdisc *root;
84 u32 flags;
85 enum tk_offsets tk_offset;
86 int clockid;
87 bool offloaded;
88 bool detected_mqprio;
89 bool broken_mqprio;
90 atomic64_t picos_per_byte; /* Using picoseconds because for 10Gbps+
91 * speeds it's sub-nanoseconds per byte
92 */
93
94 /* Protects the update side of the RCU protected current_entry */
95 spinlock_t current_entry_lock;
96 struct sched_entry __rcu *current_entry;
97 struct sched_gate_list __rcu *oper_sched;
98 struct sched_gate_list __rcu *admin_sched;
99 struct hrtimer advance_timer;
100 struct list_head taprio_list;
101 int cur_txq[TC_MAX_QUEUE];
102 u32 max_sdu[TC_MAX_QUEUE]; /* save info from the user */
103 u32 fp[TC_QOPT_MAX_QUEUE]; /* only for dump and offloading */
104 u32 txtime_delay;
105 };
106
107 struct __tc_taprio_qopt_offload {
108 refcount_t users;
109 struct tc_taprio_qopt_offload offload;
110 };
111
taprio_calculate_gate_durations(struct taprio_sched * q,struct sched_gate_list * sched)112 static void taprio_calculate_gate_durations(struct taprio_sched *q,
113 struct sched_gate_list *sched)
114 {
115 struct net_device *dev = qdisc_dev(q->root);
116 int num_tc = netdev_get_num_tc(dev);
117 struct sched_entry *entry, *cur;
118 int tc;
119
120 list_for_each_entry(entry, &sched->entries, list) {
121 u32 gates_still_open = entry->gate_mask;
122
123 /* For each traffic class, calculate each open gate duration,
124 * starting at this schedule entry and ending at the schedule
125 * entry containing a gate close event for that TC.
126 */
127 cur = entry;
128
129 do {
130 if (!gates_still_open)
131 break;
132
133 for (tc = 0; tc < num_tc; tc++) {
134 if (!(gates_still_open & BIT(tc)))
135 continue;
136
137 if (cur->gate_mask & BIT(tc))
138 entry->gate_duration[tc] += cur->interval;
139 else
140 gates_still_open &= ~BIT(tc);
141 }
142
143 cur = list_next_entry_circular(cur, &sched->entries, list);
144 } while (cur != entry);
145
146 /* Keep track of the maximum gate duration for each traffic
147 * class, taking care to not confuse a traffic class which is
148 * temporarily closed with one that is always closed.
149 */
150 for (tc = 0; tc < num_tc; tc++)
151 if (entry->gate_duration[tc] &&
152 sched->max_open_gate_duration[tc] < entry->gate_duration[tc])
153 sched->max_open_gate_duration[tc] = entry->gate_duration[tc];
154 }
155 }
156
taprio_entry_allows_tx(ktime_t skb_end_time,struct sched_entry * entry,int tc)157 static bool taprio_entry_allows_tx(ktime_t skb_end_time,
158 struct sched_entry *entry, int tc)
159 {
160 return ktime_before(skb_end_time, entry->gate_close_time[tc]);
161 }
162
sched_base_time(const struct sched_gate_list * sched)163 static ktime_t sched_base_time(const struct sched_gate_list *sched)
164 {
165 if (!sched)
166 return KTIME_MAX;
167
168 return ns_to_ktime(sched->base_time);
169 }
170
taprio_mono_to_any(const struct taprio_sched * q,ktime_t mono)171 static ktime_t taprio_mono_to_any(const struct taprio_sched *q, ktime_t mono)
172 {
173 /* This pairs with WRITE_ONCE() in taprio_parse_clockid() */
174 enum tk_offsets tk_offset = READ_ONCE(q->tk_offset);
175
176 switch (tk_offset) {
177 case TK_OFFS_MAX:
178 return mono;
179 default:
180 return ktime_mono_to_any(mono, tk_offset);
181 }
182 }
183
taprio_get_time(const struct taprio_sched * q)184 static ktime_t taprio_get_time(const struct taprio_sched *q)
185 {
186 return taprio_mono_to_any(q, ktime_get());
187 }
188
taprio_free_sched_cb(struct rcu_head * head)189 static void taprio_free_sched_cb(struct rcu_head *head)
190 {
191 struct sched_gate_list *sched = container_of(head, struct sched_gate_list, rcu);
192 struct sched_entry *entry, *n;
193
194 list_for_each_entry_safe(entry, n, &sched->entries, list) {
195 list_del(&entry->list);
196 kfree(entry);
197 }
198
199 kfree(sched);
200 }
201
switch_schedules(struct taprio_sched * q,struct sched_gate_list ** admin,struct sched_gate_list ** oper)202 static void switch_schedules(struct taprio_sched *q,
203 struct sched_gate_list **admin,
204 struct sched_gate_list **oper)
205 {
206 rcu_assign_pointer(q->oper_sched, *admin);
207 rcu_assign_pointer(q->admin_sched, NULL);
208
209 if (*oper)
210 call_rcu(&(*oper)->rcu, taprio_free_sched_cb);
211
212 *oper = *admin;
213 *admin = NULL;
214 }
215
216 /* Get how much time has been already elapsed in the current cycle. */
get_cycle_time_elapsed(struct sched_gate_list * sched,ktime_t time)217 static s32 get_cycle_time_elapsed(struct sched_gate_list *sched, ktime_t time)
218 {
219 ktime_t time_since_sched_start;
220 s32 time_elapsed;
221
222 time_since_sched_start = ktime_sub(time, sched->base_time);
223 div_s64_rem(time_since_sched_start, sched->cycle_time, &time_elapsed);
224
225 return time_elapsed;
226 }
227
get_interval_end_time(struct sched_gate_list * sched,struct sched_gate_list * admin,struct sched_entry * entry,ktime_t intv_start)228 static ktime_t get_interval_end_time(struct sched_gate_list *sched,
229 struct sched_gate_list *admin,
230 struct sched_entry *entry,
231 ktime_t intv_start)
232 {
233 s32 cycle_elapsed = get_cycle_time_elapsed(sched, intv_start);
234 ktime_t intv_end, cycle_ext_end, cycle_end;
235
236 cycle_end = ktime_add_ns(intv_start, sched->cycle_time - cycle_elapsed);
237 intv_end = ktime_add_ns(intv_start, entry->interval);
238 cycle_ext_end = ktime_add(cycle_end, sched->cycle_time_extension);
239
240 if (ktime_before(intv_end, cycle_end))
241 return intv_end;
242 else if (admin && admin != sched &&
243 ktime_after(admin->base_time, cycle_end) &&
244 ktime_before(admin->base_time, cycle_ext_end))
245 return admin->base_time;
246 else
247 return cycle_end;
248 }
249
length_to_duration(struct taprio_sched * q,int len)250 static int length_to_duration(struct taprio_sched *q, int len)
251 {
252 return div_u64(len * atomic64_read(&q->picos_per_byte), PSEC_PER_NSEC);
253 }
254
duration_to_length(struct taprio_sched * q,u64 duration)255 static int duration_to_length(struct taprio_sched *q, u64 duration)
256 {
257 return div_u64(duration * PSEC_PER_NSEC, atomic64_read(&q->picos_per_byte));
258 }
259
260 /* Sets sched->max_sdu[] and sched->max_frm_len[] to the minimum between the
261 * q->max_sdu[] requested by the user and the max_sdu dynamically determined by
262 * the maximum open gate durations at the given link speed.
263 */
taprio_update_queue_max_sdu(struct taprio_sched * q,struct sched_gate_list * sched,struct qdisc_size_table * stab)264 static void taprio_update_queue_max_sdu(struct taprio_sched *q,
265 struct sched_gate_list *sched,
266 struct qdisc_size_table *stab)
267 {
268 struct net_device *dev = qdisc_dev(q->root);
269 int num_tc = netdev_get_num_tc(dev);
270 u32 max_sdu_from_user;
271 u32 max_sdu_dynamic;
272 u32 max_sdu;
273 int tc;
274
275 for (tc = 0; tc < num_tc; tc++) {
276 max_sdu_from_user = q->max_sdu[tc] ?: U32_MAX;
277
278 /* TC gate never closes => keep the queueMaxSDU
279 * selected by the user
280 */
281 if (sched->max_open_gate_duration[tc] == sched->cycle_time) {
282 max_sdu_dynamic = U32_MAX;
283 } else {
284 u32 max_frm_len;
285
286 max_frm_len = duration_to_length(q, sched->max_open_gate_duration[tc]);
287 /* Compensate for L1 overhead from size table,
288 * but don't let the frame size go negative
289 */
290 if (stab) {
291 max_frm_len -= stab->szopts.overhead;
292 max_frm_len = max_t(int, max_frm_len,
293 dev->hard_header_len + 1);
294 }
295 max_sdu_dynamic = max_frm_len - dev->hard_header_len;
296 if (max_sdu_dynamic > dev->max_mtu)
297 max_sdu_dynamic = U32_MAX;
298 }
299
300 max_sdu = min(max_sdu_dynamic, max_sdu_from_user);
301
302 if (max_sdu != U32_MAX) {
303 sched->max_frm_len[tc] = max_sdu + dev->hard_header_len;
304 sched->max_sdu[tc] = max_sdu;
305 } else {
306 sched->max_frm_len[tc] = U32_MAX; /* never oversized */
307 sched->max_sdu[tc] = 0;
308 }
309 }
310 }
311
312 /* Returns the entry corresponding to next available interval. If
313 * validate_interval is set, it only validates whether the timestamp occurs
314 * when the gate corresponding to the skb's traffic class is open.
315 */
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)316 static struct sched_entry *find_entry_to_transmit(struct sk_buff *skb,
317 struct Qdisc *sch,
318 struct sched_gate_list *sched,
319 struct sched_gate_list *admin,
320 ktime_t time,
321 ktime_t *interval_start,
322 ktime_t *interval_end,
323 bool validate_interval)
324 {
325 ktime_t curr_intv_start, curr_intv_end, cycle_end, packet_transmit_time;
326 ktime_t earliest_txtime = KTIME_MAX, txtime, cycle, transmit_end_time;
327 struct sched_entry *entry = NULL, *entry_found = NULL;
328 struct taprio_sched *q = qdisc_priv(sch);
329 struct net_device *dev = qdisc_dev(sch);
330 bool entry_available = false;
331 s32 cycle_elapsed;
332 int tc, n;
333
334 tc = netdev_get_prio_tc_map(dev, skb->priority);
335 packet_transmit_time = length_to_duration(q, qdisc_pkt_len(skb));
336
337 *interval_start = 0;
338 *interval_end = 0;
339
340 if (!sched)
341 return NULL;
342
343 cycle = sched->cycle_time;
344 cycle_elapsed = get_cycle_time_elapsed(sched, time);
345 curr_intv_end = ktime_sub_ns(time, cycle_elapsed);
346 cycle_end = ktime_add_ns(curr_intv_end, cycle);
347
348 list_for_each_entry(entry, &sched->entries, list) {
349 curr_intv_start = curr_intv_end;
350 curr_intv_end = get_interval_end_time(sched, admin, entry,
351 curr_intv_start);
352
353 if (ktime_after(curr_intv_start, cycle_end))
354 break;
355
356 if (!(entry->gate_mask & BIT(tc)) ||
357 packet_transmit_time > entry->interval)
358 continue;
359
360 txtime = entry->next_txtime;
361
362 if (ktime_before(txtime, time) || validate_interval) {
363 transmit_end_time = ktime_add_ns(time, packet_transmit_time);
364 if ((ktime_before(curr_intv_start, time) &&
365 ktime_before(transmit_end_time, curr_intv_end)) ||
366 (ktime_after(curr_intv_start, time) && !validate_interval)) {
367 entry_found = entry;
368 *interval_start = curr_intv_start;
369 *interval_end = curr_intv_end;
370 break;
371 } else if (!entry_available && !validate_interval) {
372 /* Here, we are just trying to find out the
373 * first available interval in the next cycle.
374 */
375 entry_available = true;
376 entry_found = entry;
377 *interval_start = ktime_add_ns(curr_intv_start, cycle);
378 *interval_end = ktime_add_ns(curr_intv_end, cycle);
379 }
380 } else if (ktime_before(txtime, earliest_txtime) &&
381 !entry_available) {
382 earliest_txtime = txtime;
383 entry_found = entry;
384 n = div_s64(ktime_sub(txtime, curr_intv_start), cycle);
385 *interval_start = ktime_add(curr_intv_start, n * cycle);
386 *interval_end = ktime_add(curr_intv_end, n * cycle);
387 }
388 }
389
390 return entry_found;
391 }
392
is_valid_interval(struct sk_buff * skb,struct Qdisc * sch)393 static bool is_valid_interval(struct sk_buff *skb, struct Qdisc *sch)
394 {
395 struct taprio_sched *q = qdisc_priv(sch);
396 struct sched_gate_list *sched, *admin;
397 ktime_t interval_start, interval_end;
398 struct sched_entry *entry;
399
400 rcu_read_lock();
401 sched = rcu_dereference(q->oper_sched);
402 admin = rcu_dereference(q->admin_sched);
403
404 entry = find_entry_to_transmit(skb, sch, sched, admin, skb->tstamp,
405 &interval_start, &interval_end, true);
406 rcu_read_unlock();
407
408 return entry;
409 }
410
taprio_flags_valid(u32 flags)411 static bool taprio_flags_valid(u32 flags)
412 {
413 /* Make sure no other flag bits are set. */
414 if (flags & ~(TCA_TAPRIO_ATTR_FLAG_TXTIME_ASSIST |
415 TCA_TAPRIO_ATTR_FLAG_FULL_OFFLOAD))
416 return false;
417 /* txtime-assist and full offload are mutually exclusive */
418 if ((flags & TCA_TAPRIO_ATTR_FLAG_TXTIME_ASSIST) &&
419 (flags & TCA_TAPRIO_ATTR_FLAG_FULL_OFFLOAD))
420 return false;
421 return true;
422 }
423
424 /* This returns the tstamp value set by TCP in terms of the set clock. */
get_tcp_tstamp(struct taprio_sched * q,struct sk_buff * skb)425 static ktime_t get_tcp_tstamp(struct taprio_sched *q, struct sk_buff *skb)
426 {
427 unsigned int offset = skb_network_offset(skb);
428 const struct ipv6hdr *ipv6h;
429 const struct iphdr *iph;
430 struct ipv6hdr _ipv6h;
431
432 ipv6h = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
433 if (!ipv6h)
434 return 0;
435
436 if (ipv6h->version == 4) {
437 iph = (struct iphdr *)ipv6h;
438 offset += iph->ihl * 4;
439
440 /* special-case 6in4 tunnelling, as that is a common way to get
441 * v6 connectivity in the home
442 */
443 if (iph->protocol == IPPROTO_IPV6) {
444 ipv6h = skb_header_pointer(skb, offset,
445 sizeof(_ipv6h), &_ipv6h);
446
447 if (!ipv6h || ipv6h->nexthdr != IPPROTO_TCP)
448 return 0;
449 } else if (iph->protocol != IPPROTO_TCP) {
450 return 0;
451 }
452 } else if (ipv6h->version == 6 && ipv6h->nexthdr != IPPROTO_TCP) {
453 return 0;
454 }
455
456 return taprio_mono_to_any(q, skb->skb_mstamp_ns);
457 }
458
459 /* There are a few scenarios where we will have to modify the txtime from
460 * what is read from next_txtime in sched_entry. They are:
461 * 1. If txtime is in the past,
462 * a. The gate for the traffic class is currently open and packet can be
463 * transmitted before it closes, schedule the packet right away.
464 * b. If the gate corresponding to the traffic class is going to open later
465 * in the cycle, set the txtime of packet to the interval start.
466 * 2. If txtime is in the future, there are packets corresponding to the
467 * current traffic class waiting to be transmitted. So, the following
468 * possibilities exist:
469 * a. We can transmit the packet before the window containing the txtime
470 * closes.
471 * b. The window might close before the transmission can be completed
472 * successfully. So, schedule the packet in the next open window.
473 */
get_packet_txtime(struct sk_buff * skb,struct Qdisc * sch)474 static long get_packet_txtime(struct sk_buff *skb, struct Qdisc *sch)
475 {
476 ktime_t transmit_end_time, interval_end, interval_start, tcp_tstamp;
477 struct taprio_sched *q = qdisc_priv(sch);
478 struct sched_gate_list *sched, *admin;
479 ktime_t minimum_time, now, txtime;
480 int len, packet_transmit_time;
481 struct sched_entry *entry;
482 bool sched_changed;
483
484 now = taprio_get_time(q);
485 minimum_time = ktime_add_ns(now, q->txtime_delay);
486
487 tcp_tstamp = get_tcp_tstamp(q, skb);
488 minimum_time = max_t(ktime_t, minimum_time, tcp_tstamp);
489
490 rcu_read_lock();
491 admin = rcu_dereference(q->admin_sched);
492 sched = rcu_dereference(q->oper_sched);
493 if (admin && ktime_after(minimum_time, admin->base_time))
494 switch_schedules(q, &admin, &sched);
495
496 /* Until the schedule starts, all the queues are open */
497 if (!sched || ktime_before(minimum_time, sched->base_time)) {
498 txtime = minimum_time;
499 goto done;
500 }
501
502 len = qdisc_pkt_len(skb);
503 packet_transmit_time = length_to_duration(q, len);
504
505 do {
506 sched_changed = false;
507
508 entry = find_entry_to_transmit(skb, sch, sched, admin,
509 minimum_time,
510 &interval_start, &interval_end,
511 false);
512 if (!entry) {
513 txtime = 0;
514 goto done;
515 }
516
517 txtime = entry->next_txtime;
518 txtime = max_t(ktime_t, txtime, minimum_time);
519 txtime = max_t(ktime_t, txtime, interval_start);
520
521 if (admin && admin != sched &&
522 ktime_after(txtime, admin->base_time)) {
523 sched = admin;
524 sched_changed = true;
525 continue;
526 }
527
528 transmit_end_time = ktime_add(txtime, packet_transmit_time);
529 minimum_time = transmit_end_time;
530
531 /* Update the txtime of current entry to the next time it's
532 * interval starts.
533 */
534 if (ktime_after(transmit_end_time, interval_end))
535 entry->next_txtime = ktime_add(interval_start, sched->cycle_time);
536 } while (sched_changed || ktime_after(transmit_end_time, interval_end));
537
538 entry->next_txtime = transmit_end_time;
539
540 done:
541 rcu_read_unlock();
542 return txtime;
543 }
544
545 /* Devices with full offload are expected to honor this in hardware */
taprio_skb_exceeds_queue_max_sdu(struct Qdisc * sch,struct sk_buff * skb)546 static bool taprio_skb_exceeds_queue_max_sdu(struct Qdisc *sch,
547 struct sk_buff *skb)
548 {
549 struct taprio_sched *q = qdisc_priv(sch);
550 struct net_device *dev = qdisc_dev(sch);
551 struct sched_gate_list *sched;
552 int prio = skb->priority;
553 bool exceeds = false;
554 u8 tc;
555
556 tc = netdev_get_prio_tc_map(dev, prio);
557
558 rcu_read_lock();
559 sched = rcu_dereference(q->oper_sched);
560 if (sched && skb->len > sched->max_frm_len[tc])
561 exceeds = true;
562 rcu_read_unlock();
563
564 return exceeds;
565 }
566
taprio_enqueue_one(struct sk_buff * skb,struct Qdisc * sch,struct Qdisc * child,struct sk_buff ** to_free)567 static int taprio_enqueue_one(struct sk_buff *skb, struct Qdisc *sch,
568 struct Qdisc *child, struct sk_buff **to_free)
569 {
570 struct taprio_sched *q = qdisc_priv(sch);
571
572 /* sk_flags are only safe to use on full sockets. */
573 if (skb->sk && sk_fullsock(skb->sk) && sock_flag(skb->sk, SOCK_TXTIME)) {
574 if (!is_valid_interval(skb, sch))
575 return qdisc_drop(skb, sch, to_free);
576 } else if (TXTIME_ASSIST_IS_ENABLED(q->flags)) {
577 skb->tstamp = get_packet_txtime(skb, sch);
578 if (!skb->tstamp)
579 return qdisc_drop(skb, sch, to_free);
580 }
581
582 qdisc_qstats_backlog_inc(sch, skb);
583 sch->q.qlen++;
584
585 return qdisc_enqueue(skb, child, to_free);
586 }
587
taprio_enqueue_segmented(struct sk_buff * skb,struct Qdisc * sch,struct Qdisc * child,struct sk_buff ** to_free)588 static int taprio_enqueue_segmented(struct sk_buff *skb, struct Qdisc *sch,
589 struct Qdisc *child,
590 struct sk_buff **to_free)
591 {
592 unsigned int slen = 0, numsegs = 0, len = qdisc_pkt_len(skb);
593 netdev_features_t features = netif_skb_features(skb);
594 struct sk_buff *segs, *nskb;
595 int ret;
596
597 segs = skb_gso_segment(skb, features & ~NETIF_F_GSO_MASK);
598 if (IS_ERR_OR_NULL(segs))
599 return qdisc_drop(skb, sch, to_free);
600
601 skb_list_walk_safe(segs, segs, nskb) {
602 skb_mark_not_on_list(segs);
603 qdisc_skb_cb(segs)->pkt_len = segs->len;
604 slen += segs->len;
605
606 /* FIXME: we should be segmenting to a smaller size
607 * rather than dropping these
608 */
609 if (taprio_skb_exceeds_queue_max_sdu(sch, segs))
610 ret = qdisc_drop(segs, sch, to_free);
611 else
612 ret = taprio_enqueue_one(segs, sch, child, to_free);
613
614 if (ret != NET_XMIT_SUCCESS) {
615 if (net_xmit_drop_count(ret))
616 qdisc_qstats_drop(sch);
617 } else {
618 numsegs++;
619 }
620 }
621
622 if (numsegs > 1)
623 qdisc_tree_reduce_backlog(sch, 1 - numsegs, len - slen);
624 consume_skb(skb);
625
626 return numsegs > 0 ? NET_XMIT_SUCCESS : NET_XMIT_DROP;
627 }
628
629 /* Will not be called in the full offload case, since the TX queues are
630 * attached to the Qdisc created using qdisc_create_dflt()
631 */
taprio_enqueue(struct sk_buff * skb,struct Qdisc * sch,struct sk_buff ** to_free)632 static int taprio_enqueue(struct sk_buff *skb, struct Qdisc *sch,
633 struct sk_buff **to_free)
634 {
635 struct taprio_sched *q = qdisc_priv(sch);
636 struct Qdisc *child;
637 int queue;
638
639 queue = skb_get_queue_mapping(skb);
640
641 child = q->qdiscs[queue];
642 if (unlikely(!child))
643 return qdisc_drop(skb, sch, to_free);
644
645 if (taprio_skb_exceeds_queue_max_sdu(sch, skb)) {
646 /* Large packets might not be transmitted when the transmission
647 * duration exceeds any configured interval. Therefore, segment
648 * the skb into smaller chunks. Drivers with full offload are
649 * expected to handle this in hardware.
650 */
651 if (skb_is_gso(skb))
652 return taprio_enqueue_segmented(skb, sch, child,
653 to_free);
654
655 return qdisc_drop(skb, sch, to_free);
656 }
657
658 return taprio_enqueue_one(skb, sch, child, to_free);
659 }
660
taprio_peek(struct Qdisc * sch)661 static struct sk_buff *taprio_peek(struct Qdisc *sch)
662 {
663 WARN_ONCE(1, "taprio only supports operating as root qdisc, peek() not implemented");
664 return NULL;
665 }
666
taprio_set_budgets(struct taprio_sched * q,struct sched_gate_list * sched,struct sched_entry * entry)667 static void taprio_set_budgets(struct taprio_sched *q,
668 struct sched_gate_list *sched,
669 struct sched_entry *entry)
670 {
671 struct net_device *dev = qdisc_dev(q->root);
672 int num_tc = netdev_get_num_tc(dev);
673 int tc, budget;
674
675 for (tc = 0; tc < num_tc; tc++) {
676 /* Traffic classes which never close have infinite budget */
677 if (entry->gate_duration[tc] == sched->cycle_time)
678 budget = INT_MAX;
679 else
680 budget = div64_u64((u64)entry->gate_duration[tc] * PSEC_PER_NSEC,
681 atomic64_read(&q->picos_per_byte));
682
683 atomic_set(&entry->budget[tc], budget);
684 }
685 }
686
687 /* When an skb is sent, it consumes from the budget of all traffic classes */
taprio_update_budgets(struct sched_entry * entry,size_t len,int tc_consumed,int num_tc)688 static int taprio_update_budgets(struct sched_entry *entry, size_t len,
689 int tc_consumed, int num_tc)
690 {
691 int tc, budget, new_budget = 0;
692
693 for (tc = 0; tc < num_tc; tc++) {
694 budget = atomic_read(&entry->budget[tc]);
695 /* Don't consume from infinite budget */
696 if (budget == INT_MAX) {
697 if (tc == tc_consumed)
698 new_budget = budget;
699 continue;
700 }
701
702 if (tc == tc_consumed)
703 new_budget = atomic_sub_return(len, &entry->budget[tc]);
704 else
705 atomic_sub(len, &entry->budget[tc]);
706 }
707
708 return new_budget;
709 }
710
taprio_dequeue_from_txq(struct Qdisc * sch,int txq,struct sched_entry * entry,u32 gate_mask)711 static struct sk_buff *taprio_dequeue_from_txq(struct Qdisc *sch, int txq,
712 struct sched_entry *entry,
713 u32 gate_mask)
714 {
715 struct taprio_sched *q = qdisc_priv(sch);
716 struct net_device *dev = qdisc_dev(sch);
717 struct Qdisc *child = q->qdiscs[txq];
718 int num_tc = netdev_get_num_tc(dev);
719 struct sk_buff *skb;
720 ktime_t guard;
721 int prio;
722 int len;
723 u8 tc;
724
725 if (unlikely(!child))
726 return NULL;
727
728 if (TXTIME_ASSIST_IS_ENABLED(q->flags))
729 goto skip_peek_checks;
730
731 skb = child->ops->peek(child);
732 if (!skb)
733 return NULL;
734
735 prio = skb->priority;
736 tc = netdev_get_prio_tc_map(dev, prio);
737
738 if (!(gate_mask & BIT(tc)))
739 return NULL;
740
741 len = qdisc_pkt_len(skb);
742 guard = ktime_add_ns(taprio_get_time(q), length_to_duration(q, len));
743
744 /* In the case that there's no gate entry, there's no
745 * guard band ...
746 */
747 if (gate_mask != TAPRIO_ALL_GATES_OPEN &&
748 !taprio_entry_allows_tx(guard, entry, tc))
749 return NULL;
750
751 /* ... and no budget. */
752 if (gate_mask != TAPRIO_ALL_GATES_OPEN &&
753 taprio_update_budgets(entry, len, tc, num_tc) < 0)
754 return NULL;
755
756 skip_peek_checks:
757 skb = child->ops->dequeue(child);
758 if (unlikely(!skb))
759 return NULL;
760
761 qdisc_bstats_update(sch, skb);
762 qdisc_qstats_backlog_dec(sch, skb);
763 sch->q.qlen--;
764
765 return skb;
766 }
767
taprio_next_tc_txq(struct net_device * dev,int tc,int * txq)768 static void taprio_next_tc_txq(struct net_device *dev, int tc, int *txq)
769 {
770 int offset = dev->tc_to_txq[tc].offset;
771 int count = dev->tc_to_txq[tc].count;
772
773 (*txq)++;
774 if (*txq == offset + count)
775 *txq = offset;
776 }
777
778 /* Prioritize higher traffic classes, and select among TXQs belonging to the
779 * same TC using round robin
780 */
taprio_dequeue_tc_priority(struct Qdisc * sch,struct sched_entry * entry,u32 gate_mask)781 static struct sk_buff *taprio_dequeue_tc_priority(struct Qdisc *sch,
782 struct sched_entry *entry,
783 u32 gate_mask)
784 {
785 struct taprio_sched *q = qdisc_priv(sch);
786 struct net_device *dev = qdisc_dev(sch);
787 int num_tc = netdev_get_num_tc(dev);
788 struct sk_buff *skb;
789 int tc;
790
791 for (tc = num_tc - 1; tc >= 0; tc--) {
792 int first_txq = q->cur_txq[tc];
793
794 if (!(gate_mask & BIT(tc)))
795 continue;
796
797 do {
798 skb = taprio_dequeue_from_txq(sch, q->cur_txq[tc],
799 entry, gate_mask);
800
801 taprio_next_tc_txq(dev, tc, &q->cur_txq[tc]);
802
803 if (q->cur_txq[tc] >= dev->num_tx_queues)
804 q->cur_txq[tc] = first_txq;
805
806 if (skb)
807 return skb;
808 } while (q->cur_txq[tc] != first_txq);
809 }
810
811 return NULL;
812 }
813
814 /* Broken way of prioritizing smaller TXQ indices and ignoring the traffic
815 * class other than to determine whether the gate is open or not
816 */
taprio_dequeue_txq_priority(struct Qdisc * sch,struct sched_entry * entry,u32 gate_mask)817 static struct sk_buff *taprio_dequeue_txq_priority(struct Qdisc *sch,
818 struct sched_entry *entry,
819 u32 gate_mask)
820 {
821 struct net_device *dev = qdisc_dev(sch);
822 struct sk_buff *skb;
823 int i;
824
825 for (i = 0; i < dev->num_tx_queues; i++) {
826 skb = taprio_dequeue_from_txq(sch, i, entry, gate_mask);
827 if (skb)
828 return skb;
829 }
830
831 return NULL;
832 }
833
834 /* Will not be called in the full offload case, since the TX queues are
835 * attached to the Qdisc created using qdisc_create_dflt()
836 */
taprio_dequeue(struct Qdisc * sch)837 static struct sk_buff *taprio_dequeue(struct Qdisc *sch)
838 {
839 struct taprio_sched *q = qdisc_priv(sch);
840 struct sk_buff *skb = NULL;
841 struct sched_entry *entry;
842 u32 gate_mask;
843
844 rcu_read_lock();
845 entry = rcu_dereference(q->current_entry);
846 /* if there's no entry, it means that the schedule didn't
847 * start yet, so force all gates to be open, this is in
848 * accordance to IEEE 802.1Qbv-2015 Section 8.6.9.4.5
849 * "AdminGateStates"
850 */
851 gate_mask = entry ? entry->gate_mask : TAPRIO_ALL_GATES_OPEN;
852 if (!gate_mask)
853 goto done;
854
855 if (static_branch_unlikely(&taprio_have_broken_mqprio) &&
856 !static_branch_likely(&taprio_have_working_mqprio)) {
857 /* Single NIC kind which is broken */
858 skb = taprio_dequeue_txq_priority(sch, entry, gate_mask);
859 } else if (static_branch_likely(&taprio_have_working_mqprio) &&
860 !static_branch_unlikely(&taprio_have_broken_mqprio)) {
861 /* Single NIC kind which prioritizes properly */
862 skb = taprio_dequeue_tc_priority(sch, entry, gate_mask);
863 } else {
864 /* Mixed NIC kinds present in system, need dynamic testing */
865 if (q->broken_mqprio)
866 skb = taprio_dequeue_txq_priority(sch, entry, gate_mask);
867 else
868 skb = taprio_dequeue_tc_priority(sch, entry, gate_mask);
869 }
870
871 done:
872 rcu_read_unlock();
873
874 return skb;
875 }
876
should_restart_cycle(const struct sched_gate_list * oper,const struct sched_entry * entry)877 static bool should_restart_cycle(const struct sched_gate_list *oper,
878 const struct sched_entry *entry)
879 {
880 if (list_is_last(&entry->list, &oper->entries))
881 return true;
882
883 if (ktime_compare(entry->end_time, oper->cycle_end_time) == 0)
884 return true;
885
886 return false;
887 }
888
should_change_schedules(const struct sched_gate_list * admin,const struct sched_gate_list * oper,ktime_t end_time)889 static bool should_change_schedules(const struct sched_gate_list *admin,
890 const struct sched_gate_list *oper,
891 ktime_t end_time)
892 {
893 ktime_t next_base_time, extension_time;
894
895 if (!admin)
896 return false;
897
898 next_base_time = sched_base_time(admin);
899
900 /* This is the simple case, the end_time would fall after
901 * the next schedule base_time.
902 */
903 if (ktime_compare(next_base_time, end_time) <= 0)
904 return true;
905
906 /* This is the cycle_time_extension case, if the end_time
907 * plus the amount that can be extended would fall after the
908 * next schedule base_time, we can extend the current schedule
909 * for that amount.
910 */
911 extension_time = ktime_add_ns(end_time, oper->cycle_time_extension);
912
913 /* FIXME: the IEEE 802.1Q-2018 Specification isn't clear about
914 * how precisely the extension should be made. So after
915 * conformance testing, this logic may change.
916 */
917 if (ktime_compare(next_base_time, extension_time) <= 0)
918 return true;
919
920 return false;
921 }
922
advance_sched(struct hrtimer * timer)923 static enum hrtimer_restart advance_sched(struct hrtimer *timer)
924 {
925 struct taprio_sched *q = container_of(timer, struct taprio_sched,
926 advance_timer);
927 struct net_device *dev = qdisc_dev(q->root);
928 struct sched_gate_list *oper, *admin;
929 int num_tc = netdev_get_num_tc(dev);
930 struct sched_entry *entry, *next;
931 struct Qdisc *sch = q->root;
932 ktime_t end_time;
933 int tc;
934
935 spin_lock(&q->current_entry_lock);
936 entry = rcu_dereference_protected(q->current_entry,
937 lockdep_is_held(&q->current_entry_lock));
938 oper = rcu_dereference_protected(q->oper_sched,
939 lockdep_is_held(&q->current_entry_lock));
940 admin = rcu_dereference_protected(q->admin_sched,
941 lockdep_is_held(&q->current_entry_lock));
942
943 if (!oper)
944 switch_schedules(q, &admin, &oper);
945
946 /* This can happen in two cases: 1. this is the very first run
947 * of this function (i.e. we weren't running any schedule
948 * previously); 2. The previous schedule just ended. The first
949 * entry of all schedules are pre-calculated during the
950 * schedule initialization.
951 */
952 if (unlikely(!entry || entry->end_time == oper->base_time)) {
953 next = list_first_entry(&oper->entries, struct sched_entry,
954 list);
955 end_time = next->end_time;
956 goto first_run;
957 }
958
959 if (should_restart_cycle(oper, entry)) {
960 next = list_first_entry(&oper->entries, struct sched_entry,
961 list);
962 oper->cycle_end_time = ktime_add_ns(oper->cycle_end_time,
963 oper->cycle_time);
964 } else {
965 next = list_next_entry(entry, list);
966 }
967
968 end_time = ktime_add_ns(entry->end_time, next->interval);
969 end_time = min_t(ktime_t, end_time, oper->cycle_end_time);
970
971 for (tc = 0; tc < num_tc; tc++) {
972 if (next->gate_duration[tc] == oper->cycle_time)
973 next->gate_close_time[tc] = KTIME_MAX;
974 else
975 next->gate_close_time[tc] = ktime_add_ns(entry->end_time,
976 next->gate_duration[tc]);
977 }
978
979 if (should_change_schedules(admin, oper, end_time)) {
980 /* Set things so the next time this runs, the new
981 * schedule runs.
982 */
983 end_time = sched_base_time(admin);
984 switch_schedules(q, &admin, &oper);
985 }
986
987 next->end_time = end_time;
988 taprio_set_budgets(q, oper, next);
989
990 first_run:
991 rcu_assign_pointer(q->current_entry, next);
992 spin_unlock(&q->current_entry_lock);
993
994 hrtimer_set_expires(&q->advance_timer, end_time);
995
996 rcu_read_lock();
997 __netif_schedule(sch);
998 rcu_read_unlock();
999
1000 return HRTIMER_RESTART;
1001 }
1002
1003 static const struct nla_policy entry_policy[TCA_TAPRIO_SCHED_ENTRY_MAX + 1] = {
1004 [TCA_TAPRIO_SCHED_ENTRY_INDEX] = { .type = NLA_U32 },
1005 [TCA_TAPRIO_SCHED_ENTRY_CMD] = { .type = NLA_U8 },
1006 [TCA_TAPRIO_SCHED_ENTRY_GATE_MASK] = { .type = NLA_U32 },
1007 [TCA_TAPRIO_SCHED_ENTRY_INTERVAL] = { .type = NLA_U32 },
1008 };
1009
1010 static const struct nla_policy taprio_tc_policy[TCA_TAPRIO_TC_ENTRY_MAX + 1] = {
1011 [TCA_TAPRIO_TC_ENTRY_INDEX] = NLA_POLICY_MAX(NLA_U32,
1012 TC_QOPT_MAX_QUEUE),
1013 [TCA_TAPRIO_TC_ENTRY_MAX_SDU] = { .type = NLA_U32 },
1014 [TCA_TAPRIO_TC_ENTRY_FP] = NLA_POLICY_RANGE(NLA_U32,
1015 TC_FP_EXPRESS,
1016 TC_FP_PREEMPTIBLE),
1017 };
1018
1019 static struct netlink_range_validation_signed taprio_cycle_time_range = {
1020 .min = 0,
1021 .max = INT_MAX,
1022 };
1023
1024 static const struct nla_policy taprio_policy[TCA_TAPRIO_ATTR_MAX + 1] = {
1025 [TCA_TAPRIO_ATTR_PRIOMAP] = {
1026 .len = sizeof(struct tc_mqprio_qopt)
1027 },
1028 [TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST] = { .type = NLA_NESTED },
1029 [TCA_TAPRIO_ATTR_SCHED_BASE_TIME] = { .type = NLA_S64 },
1030 [TCA_TAPRIO_ATTR_SCHED_SINGLE_ENTRY] = { .type = NLA_NESTED },
1031 [TCA_TAPRIO_ATTR_SCHED_CLOCKID] = { .type = NLA_S32 },
1032 [TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME] =
1033 NLA_POLICY_FULL_RANGE_SIGNED(NLA_S64, &taprio_cycle_time_range),
1034 [TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME_EXTENSION] = { .type = NLA_S64 },
1035 [TCA_TAPRIO_ATTR_FLAGS] = { .type = NLA_U32 },
1036 [TCA_TAPRIO_ATTR_TXTIME_DELAY] = { .type = NLA_U32 },
1037 [TCA_TAPRIO_ATTR_TC_ENTRY] = { .type = NLA_NESTED },
1038 };
1039
fill_sched_entry(struct taprio_sched * q,struct nlattr ** tb,struct sched_entry * entry,struct netlink_ext_ack * extack)1040 static int fill_sched_entry(struct taprio_sched *q, struct nlattr **tb,
1041 struct sched_entry *entry,
1042 struct netlink_ext_ack *extack)
1043 {
1044 int min_duration = length_to_duration(q, ETH_ZLEN);
1045 u32 interval = 0;
1046
1047 if (tb[TCA_TAPRIO_SCHED_ENTRY_CMD])
1048 entry->command = nla_get_u8(
1049 tb[TCA_TAPRIO_SCHED_ENTRY_CMD]);
1050
1051 if (tb[TCA_TAPRIO_SCHED_ENTRY_GATE_MASK])
1052 entry->gate_mask = nla_get_u32(
1053 tb[TCA_TAPRIO_SCHED_ENTRY_GATE_MASK]);
1054
1055 if (tb[TCA_TAPRIO_SCHED_ENTRY_INTERVAL])
1056 interval = nla_get_u32(
1057 tb[TCA_TAPRIO_SCHED_ENTRY_INTERVAL]);
1058
1059 /* The interval should allow at least the minimum ethernet
1060 * frame to go out.
1061 */
1062 if (interval < min_duration) {
1063 NL_SET_ERR_MSG(extack, "Invalid interval for schedule entry");
1064 return -EINVAL;
1065 }
1066
1067 entry->interval = interval;
1068
1069 return 0;
1070 }
1071
parse_sched_entry(struct taprio_sched * q,struct nlattr * n,struct sched_entry * entry,int index,struct netlink_ext_ack * extack)1072 static int parse_sched_entry(struct taprio_sched *q, struct nlattr *n,
1073 struct sched_entry *entry, int index,
1074 struct netlink_ext_ack *extack)
1075 {
1076 struct nlattr *tb[TCA_TAPRIO_SCHED_ENTRY_MAX + 1] = { };
1077 int err;
1078
1079 err = nla_parse_nested_deprecated(tb, TCA_TAPRIO_SCHED_ENTRY_MAX, n,
1080 entry_policy, NULL);
1081 if (err < 0) {
1082 NL_SET_ERR_MSG(extack, "Could not parse nested entry");
1083 return -EINVAL;
1084 }
1085
1086 entry->index = index;
1087
1088 return fill_sched_entry(q, tb, entry, extack);
1089 }
1090
parse_sched_list(struct taprio_sched * q,struct nlattr * list,struct sched_gate_list * sched,struct netlink_ext_ack * extack)1091 static int parse_sched_list(struct taprio_sched *q, struct nlattr *list,
1092 struct sched_gate_list *sched,
1093 struct netlink_ext_ack *extack)
1094 {
1095 struct nlattr *n;
1096 int err, rem;
1097 int i = 0;
1098
1099 if (!list)
1100 return -EINVAL;
1101
1102 nla_for_each_nested(n, list, rem) {
1103 struct sched_entry *entry;
1104
1105 if (nla_type(n) != TCA_TAPRIO_SCHED_ENTRY) {
1106 NL_SET_ERR_MSG(extack, "Attribute is not of type 'entry'");
1107 continue;
1108 }
1109
1110 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
1111 if (!entry) {
1112 NL_SET_ERR_MSG(extack, "Not enough memory for entry");
1113 return -ENOMEM;
1114 }
1115
1116 err = parse_sched_entry(q, n, entry, i, extack);
1117 if (err < 0) {
1118 kfree(entry);
1119 return err;
1120 }
1121
1122 list_add_tail(&entry->list, &sched->entries);
1123 i++;
1124 }
1125
1126 sched->num_entries = i;
1127
1128 return i;
1129 }
1130
parse_taprio_schedule(struct taprio_sched * q,struct nlattr ** tb,struct sched_gate_list * new,struct netlink_ext_ack * extack)1131 static int parse_taprio_schedule(struct taprio_sched *q, struct nlattr **tb,
1132 struct sched_gate_list *new,
1133 struct netlink_ext_ack *extack)
1134 {
1135 int err = 0;
1136
1137 if (tb[TCA_TAPRIO_ATTR_SCHED_SINGLE_ENTRY]) {
1138 NL_SET_ERR_MSG(extack, "Adding a single entry is not supported");
1139 return -ENOTSUPP;
1140 }
1141
1142 if (tb[TCA_TAPRIO_ATTR_SCHED_BASE_TIME])
1143 new->base_time = nla_get_s64(tb[TCA_TAPRIO_ATTR_SCHED_BASE_TIME]);
1144
1145 if (tb[TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME_EXTENSION])
1146 new->cycle_time_extension = nla_get_s64(tb[TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME_EXTENSION]);
1147
1148 if (tb[TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME])
1149 new->cycle_time = nla_get_s64(tb[TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME]);
1150
1151 if (tb[TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST])
1152 err = parse_sched_list(q, tb[TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST],
1153 new, extack);
1154 if (err < 0)
1155 return err;
1156
1157 if (!new->cycle_time) {
1158 struct sched_entry *entry;
1159 ktime_t cycle = 0;
1160
1161 list_for_each_entry(entry, &new->entries, list)
1162 cycle = ktime_add_ns(cycle, entry->interval);
1163
1164 if (cycle < 0 || cycle > INT_MAX) {
1165 NL_SET_ERR_MSG(extack, "'cycle_time' is too big");
1166 return -EINVAL;
1167 }
1168
1169 new->cycle_time = cycle;
1170 }
1171
1172 if (new->cycle_time < new->num_entries * length_to_duration(q, ETH_ZLEN)) {
1173 NL_SET_ERR_MSG(extack, "'cycle_time' is too small");
1174 return -EINVAL;
1175 }
1176
1177 taprio_calculate_gate_durations(q, new);
1178
1179 return 0;
1180 }
1181
taprio_parse_mqprio_opt(struct net_device * dev,struct tc_mqprio_qopt * qopt,struct netlink_ext_ack * extack,u32 taprio_flags)1182 static int taprio_parse_mqprio_opt(struct net_device *dev,
1183 struct tc_mqprio_qopt *qopt,
1184 struct netlink_ext_ack *extack,
1185 u32 taprio_flags)
1186 {
1187 bool allow_overlapping_txqs = TXTIME_ASSIST_IS_ENABLED(taprio_flags);
1188
1189 if (!qopt) {
1190 if (!dev->num_tc) {
1191 NL_SET_ERR_MSG(extack, "'mqprio' configuration is necessary");
1192 return -EINVAL;
1193 }
1194 return 0;
1195 }
1196
1197 /* taprio imposes that traffic classes map 1:n to tx queues */
1198 if (qopt->num_tc > dev->num_tx_queues) {
1199 NL_SET_ERR_MSG(extack, "Number of traffic classes is greater than number of HW queues");
1200 return -EINVAL;
1201 }
1202
1203 /* For some reason, in txtime-assist mode, we allow TXQ ranges for
1204 * different TCs to overlap, and just validate the TXQ ranges.
1205 */
1206 return mqprio_validate_qopt(dev, qopt, true, allow_overlapping_txqs,
1207 extack);
1208 }
1209
taprio_get_start_time(struct Qdisc * sch,struct sched_gate_list * sched,ktime_t * start)1210 static int taprio_get_start_time(struct Qdisc *sch,
1211 struct sched_gate_list *sched,
1212 ktime_t *start)
1213 {
1214 struct taprio_sched *q = qdisc_priv(sch);
1215 ktime_t now, base, cycle;
1216 s64 n;
1217
1218 base = sched_base_time(sched);
1219 now = taprio_get_time(q);
1220
1221 if (ktime_after(base, now)) {
1222 *start = base;
1223 return 0;
1224 }
1225
1226 cycle = sched->cycle_time;
1227
1228 /* The qdisc is expected to have at least one sched_entry. Moreover,
1229 * any entry must have 'interval' > 0. Thus if the cycle time is zero,
1230 * something went really wrong. In that case, we should warn about this
1231 * inconsistent state and return error.
1232 */
1233 if (WARN_ON(!cycle))
1234 return -EFAULT;
1235
1236 /* Schedule the start time for the beginning of the next
1237 * cycle.
1238 */
1239 n = div64_s64(ktime_sub_ns(now, base), cycle);
1240 *start = ktime_add_ns(base, (n + 1) * cycle);
1241 return 0;
1242 }
1243
setup_first_end_time(struct taprio_sched * q,struct sched_gate_list * sched,ktime_t base)1244 static void setup_first_end_time(struct taprio_sched *q,
1245 struct sched_gate_list *sched, ktime_t base)
1246 {
1247 struct net_device *dev = qdisc_dev(q->root);
1248 int num_tc = netdev_get_num_tc(dev);
1249 struct sched_entry *first;
1250 ktime_t cycle;
1251 int tc;
1252
1253 first = list_first_entry(&sched->entries,
1254 struct sched_entry, list);
1255
1256 cycle = sched->cycle_time;
1257
1258 /* FIXME: find a better place to do this */
1259 sched->cycle_end_time = ktime_add_ns(base, cycle);
1260
1261 first->end_time = ktime_add_ns(base, first->interval);
1262 taprio_set_budgets(q, sched, first);
1263
1264 for (tc = 0; tc < num_tc; tc++) {
1265 if (first->gate_duration[tc] == sched->cycle_time)
1266 first->gate_close_time[tc] = KTIME_MAX;
1267 else
1268 first->gate_close_time[tc] = ktime_add_ns(base, first->gate_duration[tc]);
1269 }
1270
1271 rcu_assign_pointer(q->current_entry, NULL);
1272 }
1273
taprio_start_sched(struct Qdisc * sch,ktime_t start,struct sched_gate_list * new)1274 static void taprio_start_sched(struct Qdisc *sch,
1275 ktime_t start, struct sched_gate_list *new)
1276 {
1277 struct taprio_sched *q = qdisc_priv(sch);
1278 ktime_t expires;
1279
1280 if (FULL_OFFLOAD_IS_ENABLED(q->flags))
1281 return;
1282
1283 expires = hrtimer_get_expires(&q->advance_timer);
1284 if (expires == 0)
1285 expires = KTIME_MAX;
1286
1287 /* If the new schedule starts before the next expiration, we
1288 * reprogram it to the earliest one, so we change the admin
1289 * schedule to the operational one at the right time.
1290 */
1291 start = min_t(ktime_t, start, expires);
1292
1293 hrtimer_start(&q->advance_timer, start, HRTIMER_MODE_ABS);
1294 }
1295
taprio_set_picos_per_byte(struct net_device * dev,struct taprio_sched * q)1296 static void taprio_set_picos_per_byte(struct net_device *dev,
1297 struct taprio_sched *q)
1298 {
1299 struct ethtool_link_ksettings ecmd;
1300 int speed = SPEED_10;
1301 int picos_per_byte;
1302 int err;
1303
1304 err = __ethtool_get_link_ksettings(dev, &ecmd);
1305 if (err < 0)
1306 goto skip;
1307
1308 if (ecmd.base.speed && ecmd.base.speed != SPEED_UNKNOWN)
1309 speed = ecmd.base.speed;
1310
1311 skip:
1312 picos_per_byte = (USEC_PER_SEC * 8) / speed;
1313
1314 atomic64_set(&q->picos_per_byte, picos_per_byte);
1315 netdev_dbg(dev, "taprio: set %s's picos_per_byte to: %lld, linkspeed: %d\n",
1316 dev->name, (long long)atomic64_read(&q->picos_per_byte),
1317 ecmd.base.speed);
1318 }
1319
taprio_dev_notifier(struct notifier_block * nb,unsigned long event,void * ptr)1320 static int taprio_dev_notifier(struct notifier_block *nb, unsigned long event,
1321 void *ptr)
1322 {
1323 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1324 struct sched_gate_list *oper, *admin;
1325 struct qdisc_size_table *stab;
1326 struct taprio_sched *q;
1327
1328 ASSERT_RTNL();
1329
1330 if (event != NETDEV_UP && event != NETDEV_CHANGE)
1331 return NOTIFY_DONE;
1332
1333 list_for_each_entry(q, &taprio_list, taprio_list) {
1334 if (dev != qdisc_dev(q->root))
1335 continue;
1336
1337 taprio_set_picos_per_byte(dev, q);
1338
1339 stab = rtnl_dereference(q->root->stab);
1340
1341 oper = rtnl_dereference(q->oper_sched);
1342 if (oper)
1343 taprio_update_queue_max_sdu(q, oper, stab);
1344
1345 admin = rtnl_dereference(q->admin_sched);
1346 if (admin)
1347 taprio_update_queue_max_sdu(q, admin, stab);
1348
1349 break;
1350 }
1351
1352 return NOTIFY_DONE;
1353 }
1354
setup_txtime(struct taprio_sched * q,struct sched_gate_list * sched,ktime_t base)1355 static void setup_txtime(struct taprio_sched *q,
1356 struct sched_gate_list *sched, ktime_t base)
1357 {
1358 struct sched_entry *entry;
1359 u64 interval = 0;
1360
1361 list_for_each_entry(entry, &sched->entries, list) {
1362 entry->next_txtime = ktime_add_ns(base, interval);
1363 interval += entry->interval;
1364 }
1365 }
1366
taprio_offload_alloc(int num_entries)1367 static struct tc_taprio_qopt_offload *taprio_offload_alloc(int num_entries)
1368 {
1369 struct __tc_taprio_qopt_offload *__offload;
1370
1371 __offload = kzalloc(struct_size(__offload, offload.entries, num_entries),
1372 GFP_KERNEL);
1373 if (!__offload)
1374 return NULL;
1375
1376 refcount_set(&__offload->users, 1);
1377
1378 return &__offload->offload;
1379 }
1380
taprio_offload_get(struct tc_taprio_qopt_offload * offload)1381 struct tc_taprio_qopt_offload *taprio_offload_get(struct tc_taprio_qopt_offload
1382 *offload)
1383 {
1384 struct __tc_taprio_qopt_offload *__offload;
1385
1386 __offload = container_of(offload, struct __tc_taprio_qopt_offload,
1387 offload);
1388
1389 refcount_inc(&__offload->users);
1390
1391 return offload;
1392 }
1393 EXPORT_SYMBOL_GPL(taprio_offload_get);
1394
taprio_offload_free(struct tc_taprio_qopt_offload * offload)1395 void taprio_offload_free(struct tc_taprio_qopt_offload *offload)
1396 {
1397 struct __tc_taprio_qopt_offload *__offload;
1398
1399 __offload = container_of(offload, struct __tc_taprio_qopt_offload,
1400 offload);
1401
1402 if (!refcount_dec_and_test(&__offload->users))
1403 return;
1404
1405 kfree(__offload);
1406 }
1407 EXPORT_SYMBOL_GPL(taprio_offload_free);
1408
1409 /* The function will only serve to keep the pointers to the "oper" and "admin"
1410 * schedules valid in relation to their base times, so when calling dump() the
1411 * users looks at the right schedules.
1412 * When using full offload, the admin configuration is promoted to oper at the
1413 * base_time in the PHC time domain. But because the system time is not
1414 * necessarily in sync with that, we can't just trigger a hrtimer to call
1415 * switch_schedules at the right hardware time.
1416 * At the moment we call this by hand right away from taprio, but in the future
1417 * it will be useful to create a mechanism for drivers to notify taprio of the
1418 * offload state (PENDING, ACTIVE, INACTIVE) so it can be visible in dump().
1419 * This is left as TODO.
1420 */
taprio_offload_config_changed(struct taprio_sched * q)1421 static void taprio_offload_config_changed(struct taprio_sched *q)
1422 {
1423 struct sched_gate_list *oper, *admin;
1424
1425 oper = rtnl_dereference(q->oper_sched);
1426 admin = rtnl_dereference(q->admin_sched);
1427
1428 switch_schedules(q, &admin, &oper);
1429 }
1430
tc_map_to_queue_mask(struct net_device * dev,u32 tc_mask)1431 static u32 tc_map_to_queue_mask(struct net_device *dev, u32 tc_mask)
1432 {
1433 u32 i, queue_mask = 0;
1434
1435 for (i = 0; i < dev->num_tc; i++) {
1436 u32 offset, count;
1437
1438 if (!(tc_mask & BIT(i)))
1439 continue;
1440
1441 offset = dev->tc_to_txq[i].offset;
1442 count = dev->tc_to_txq[i].count;
1443
1444 queue_mask |= GENMASK(offset + count - 1, offset);
1445 }
1446
1447 return queue_mask;
1448 }
1449
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)1450 static void taprio_sched_to_offload(struct net_device *dev,
1451 struct sched_gate_list *sched,
1452 struct tc_taprio_qopt_offload *offload,
1453 const struct tc_taprio_caps *caps)
1454 {
1455 struct sched_entry *entry;
1456 int i = 0;
1457
1458 offload->base_time = sched->base_time;
1459 offload->cycle_time = sched->cycle_time;
1460 offload->cycle_time_extension = sched->cycle_time_extension;
1461
1462 list_for_each_entry(entry, &sched->entries, list) {
1463 struct tc_taprio_sched_entry *e = &offload->entries[i];
1464
1465 e->command = entry->command;
1466 e->interval = entry->interval;
1467 if (caps->gate_mask_per_txq)
1468 e->gate_mask = tc_map_to_queue_mask(dev,
1469 entry->gate_mask);
1470 else
1471 e->gate_mask = entry->gate_mask;
1472
1473 i++;
1474 }
1475
1476 offload->num_entries = i;
1477 }
1478
taprio_detect_broken_mqprio(struct taprio_sched * q)1479 static void taprio_detect_broken_mqprio(struct taprio_sched *q)
1480 {
1481 struct net_device *dev = qdisc_dev(q->root);
1482 struct tc_taprio_caps caps;
1483
1484 qdisc_offload_query_caps(dev, TC_SETUP_QDISC_TAPRIO,
1485 &caps, sizeof(caps));
1486
1487 q->broken_mqprio = caps.broken_mqprio;
1488 if (q->broken_mqprio)
1489 static_branch_inc(&taprio_have_broken_mqprio);
1490 else
1491 static_branch_inc(&taprio_have_working_mqprio);
1492
1493 q->detected_mqprio = true;
1494 }
1495
taprio_cleanup_broken_mqprio(struct taprio_sched * q)1496 static void taprio_cleanup_broken_mqprio(struct taprio_sched *q)
1497 {
1498 if (!q->detected_mqprio)
1499 return;
1500
1501 if (q->broken_mqprio)
1502 static_branch_dec(&taprio_have_broken_mqprio);
1503 else
1504 static_branch_dec(&taprio_have_working_mqprio);
1505 }
1506
taprio_enable_offload(struct net_device * dev,struct taprio_sched * q,struct sched_gate_list * sched,struct netlink_ext_ack * extack)1507 static int taprio_enable_offload(struct net_device *dev,
1508 struct taprio_sched *q,
1509 struct sched_gate_list *sched,
1510 struct netlink_ext_ack *extack)
1511 {
1512 const struct net_device_ops *ops = dev->netdev_ops;
1513 struct tc_taprio_qopt_offload *offload;
1514 struct tc_taprio_caps caps;
1515 int tc, err = 0;
1516
1517 if (!ops->ndo_setup_tc) {
1518 NL_SET_ERR_MSG(extack,
1519 "Device does not support taprio offload");
1520 return -EOPNOTSUPP;
1521 }
1522
1523 qdisc_offload_query_caps(dev, TC_SETUP_QDISC_TAPRIO,
1524 &caps, sizeof(caps));
1525
1526 if (!caps.supports_queue_max_sdu) {
1527 for (tc = 0; tc < TC_MAX_QUEUE; tc++) {
1528 if (q->max_sdu[tc]) {
1529 NL_SET_ERR_MSG_MOD(extack,
1530 "Device does not handle queueMaxSDU");
1531 return -EOPNOTSUPP;
1532 }
1533 }
1534 }
1535
1536 offload = taprio_offload_alloc(sched->num_entries);
1537 if (!offload) {
1538 NL_SET_ERR_MSG(extack,
1539 "Not enough memory for enabling offload mode");
1540 return -ENOMEM;
1541 }
1542 offload->cmd = TAPRIO_CMD_REPLACE;
1543 offload->extack = extack;
1544 mqprio_qopt_reconstruct(dev, &offload->mqprio.qopt);
1545 offload->mqprio.extack = extack;
1546 taprio_sched_to_offload(dev, sched, offload, &caps);
1547 mqprio_fp_to_offload(q->fp, &offload->mqprio);
1548
1549 for (tc = 0; tc < TC_MAX_QUEUE; tc++)
1550 offload->max_sdu[tc] = q->max_sdu[tc];
1551
1552 err = ops->ndo_setup_tc(dev, TC_SETUP_QDISC_TAPRIO, offload);
1553 if (err < 0) {
1554 NL_SET_ERR_MSG_WEAK(extack,
1555 "Device failed to setup taprio offload");
1556 goto done;
1557 }
1558
1559 q->offloaded = true;
1560
1561 done:
1562 /* The offload structure may linger around via a reference taken by the
1563 * device driver, so clear up the netlink extack pointer so that the
1564 * driver isn't tempted to dereference data which stopped being valid
1565 */
1566 offload->extack = NULL;
1567 offload->mqprio.extack = NULL;
1568 taprio_offload_free(offload);
1569
1570 return err;
1571 }
1572
taprio_disable_offload(struct net_device * dev,struct taprio_sched * q,struct netlink_ext_ack * extack)1573 static int taprio_disable_offload(struct net_device *dev,
1574 struct taprio_sched *q,
1575 struct netlink_ext_ack *extack)
1576 {
1577 const struct net_device_ops *ops = dev->netdev_ops;
1578 struct tc_taprio_qopt_offload *offload;
1579 int err;
1580
1581 if (!q->offloaded)
1582 return 0;
1583
1584 offload = taprio_offload_alloc(0);
1585 if (!offload) {
1586 NL_SET_ERR_MSG(extack,
1587 "Not enough memory to disable offload mode");
1588 return -ENOMEM;
1589 }
1590 offload->cmd = TAPRIO_CMD_DESTROY;
1591
1592 err = ops->ndo_setup_tc(dev, TC_SETUP_QDISC_TAPRIO, offload);
1593 if (err < 0) {
1594 NL_SET_ERR_MSG(extack,
1595 "Device failed to disable offload");
1596 goto out;
1597 }
1598
1599 q->offloaded = false;
1600
1601 out:
1602 taprio_offload_free(offload);
1603
1604 return err;
1605 }
1606
1607 /* If full offload is enabled, the only possible clockid is the net device's
1608 * PHC. For that reason, specifying a clockid through netlink is incorrect.
1609 * For txtime-assist, it is implicitly assumed that the device's PHC is kept
1610 * in sync with the specified clockid via a user space daemon such as phc2sys.
1611 * For both software taprio and txtime-assist, the clockid is used for the
1612 * hrtimer that advances the schedule and hence mandatory.
1613 */
taprio_parse_clockid(struct Qdisc * sch,struct nlattr ** tb,struct netlink_ext_ack * extack)1614 static int taprio_parse_clockid(struct Qdisc *sch, struct nlattr **tb,
1615 struct netlink_ext_ack *extack)
1616 {
1617 struct taprio_sched *q = qdisc_priv(sch);
1618 struct net_device *dev = qdisc_dev(sch);
1619 int err = -EINVAL;
1620
1621 if (FULL_OFFLOAD_IS_ENABLED(q->flags)) {
1622 const struct ethtool_ops *ops = dev->ethtool_ops;
1623 struct ethtool_ts_info info = {
1624 .cmd = ETHTOOL_GET_TS_INFO,
1625 .phc_index = -1,
1626 };
1627
1628 if (tb[TCA_TAPRIO_ATTR_SCHED_CLOCKID]) {
1629 NL_SET_ERR_MSG(extack,
1630 "The 'clockid' cannot be specified for full offload");
1631 goto out;
1632 }
1633
1634 if (ops && ops->get_ts_info)
1635 err = ops->get_ts_info(dev, &info);
1636
1637 if (err || info.phc_index < 0) {
1638 NL_SET_ERR_MSG(extack,
1639 "Device does not have a PTP clock");
1640 err = -ENOTSUPP;
1641 goto out;
1642 }
1643 } else if (tb[TCA_TAPRIO_ATTR_SCHED_CLOCKID]) {
1644 int clockid = nla_get_s32(tb[TCA_TAPRIO_ATTR_SCHED_CLOCKID]);
1645 enum tk_offsets tk_offset;
1646
1647 /* We only support static clockids and we don't allow
1648 * for it to be modified after the first init.
1649 */
1650 if (clockid < 0 ||
1651 (q->clockid != -1 && q->clockid != clockid)) {
1652 NL_SET_ERR_MSG(extack,
1653 "Changing the 'clockid' of a running schedule is not supported");
1654 err = -ENOTSUPP;
1655 goto out;
1656 }
1657
1658 switch (clockid) {
1659 case CLOCK_REALTIME:
1660 tk_offset = TK_OFFS_REAL;
1661 break;
1662 case CLOCK_MONOTONIC:
1663 tk_offset = TK_OFFS_MAX;
1664 break;
1665 case CLOCK_BOOTTIME:
1666 tk_offset = TK_OFFS_BOOT;
1667 break;
1668 case CLOCK_TAI:
1669 tk_offset = TK_OFFS_TAI;
1670 break;
1671 default:
1672 NL_SET_ERR_MSG(extack, "Invalid 'clockid'");
1673 err = -EINVAL;
1674 goto out;
1675 }
1676 /* This pairs with READ_ONCE() in taprio_mono_to_any */
1677 WRITE_ONCE(q->tk_offset, tk_offset);
1678
1679 q->clockid = clockid;
1680 } else {
1681 NL_SET_ERR_MSG(extack, "Specifying a 'clockid' is mandatory");
1682 goto out;
1683 }
1684
1685 /* Everything went ok, return success. */
1686 err = 0;
1687
1688 out:
1689 return err;
1690 }
1691
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)1692 static int taprio_parse_tc_entry(struct Qdisc *sch,
1693 struct nlattr *opt,
1694 u32 max_sdu[TC_QOPT_MAX_QUEUE],
1695 u32 fp[TC_QOPT_MAX_QUEUE],
1696 unsigned long *seen_tcs,
1697 struct netlink_ext_ack *extack)
1698 {
1699 struct nlattr *tb[TCA_TAPRIO_TC_ENTRY_MAX + 1] = { };
1700 struct net_device *dev = qdisc_dev(sch);
1701 int err, tc;
1702 u32 val;
1703
1704 err = nla_parse_nested(tb, TCA_TAPRIO_TC_ENTRY_MAX, opt,
1705 taprio_tc_policy, extack);
1706 if (err < 0)
1707 return err;
1708
1709 if (!tb[TCA_TAPRIO_TC_ENTRY_INDEX]) {
1710 NL_SET_ERR_MSG_MOD(extack, "TC entry index missing");
1711 return -EINVAL;
1712 }
1713
1714 tc = nla_get_u32(tb[TCA_TAPRIO_TC_ENTRY_INDEX]);
1715 if (tc >= TC_QOPT_MAX_QUEUE) {
1716 NL_SET_ERR_MSG_MOD(extack, "TC entry index out of range");
1717 return -ERANGE;
1718 }
1719
1720 if (*seen_tcs & BIT(tc)) {
1721 NL_SET_ERR_MSG_MOD(extack, "Duplicate TC entry");
1722 return -EINVAL;
1723 }
1724
1725 *seen_tcs |= BIT(tc);
1726
1727 if (tb[TCA_TAPRIO_TC_ENTRY_MAX_SDU]) {
1728 val = nla_get_u32(tb[TCA_TAPRIO_TC_ENTRY_MAX_SDU]);
1729 if (val > dev->max_mtu) {
1730 NL_SET_ERR_MSG_MOD(extack, "TC max SDU exceeds device max MTU");
1731 return -ERANGE;
1732 }
1733
1734 max_sdu[tc] = val;
1735 }
1736
1737 if (tb[TCA_TAPRIO_TC_ENTRY_FP])
1738 fp[tc] = nla_get_u32(tb[TCA_TAPRIO_TC_ENTRY_FP]);
1739
1740 return 0;
1741 }
1742
taprio_parse_tc_entries(struct Qdisc * sch,struct nlattr * opt,struct netlink_ext_ack * extack)1743 static int taprio_parse_tc_entries(struct Qdisc *sch,
1744 struct nlattr *opt,
1745 struct netlink_ext_ack *extack)
1746 {
1747 struct taprio_sched *q = qdisc_priv(sch);
1748 struct net_device *dev = qdisc_dev(sch);
1749 u32 max_sdu[TC_QOPT_MAX_QUEUE];
1750 bool have_preemption = false;
1751 unsigned long seen_tcs = 0;
1752 u32 fp[TC_QOPT_MAX_QUEUE];
1753 struct nlattr *n;
1754 int tc, rem;
1755 int err = 0;
1756
1757 for (tc = 0; tc < TC_QOPT_MAX_QUEUE; tc++) {
1758 max_sdu[tc] = q->max_sdu[tc];
1759 fp[tc] = q->fp[tc];
1760 }
1761
1762 nla_for_each_nested(n, opt, rem) {
1763 if (nla_type(n) != TCA_TAPRIO_ATTR_TC_ENTRY)
1764 continue;
1765
1766 err = taprio_parse_tc_entry(sch, n, max_sdu, fp, &seen_tcs,
1767 extack);
1768 if (err)
1769 return err;
1770 }
1771
1772 for (tc = 0; tc < TC_QOPT_MAX_QUEUE; tc++) {
1773 q->max_sdu[tc] = max_sdu[tc];
1774 q->fp[tc] = fp[tc];
1775 if (fp[tc] != TC_FP_EXPRESS)
1776 have_preemption = true;
1777 }
1778
1779 if (have_preemption) {
1780 if (!FULL_OFFLOAD_IS_ENABLED(q->flags)) {
1781 NL_SET_ERR_MSG(extack,
1782 "Preemption only supported with full offload");
1783 return -EOPNOTSUPP;
1784 }
1785
1786 if (!ethtool_dev_mm_supported(dev)) {
1787 NL_SET_ERR_MSG(extack,
1788 "Device does not support preemption");
1789 return -EOPNOTSUPP;
1790 }
1791 }
1792
1793 return err;
1794 }
1795
taprio_mqprio_cmp(const struct net_device * dev,const struct tc_mqprio_qopt * mqprio)1796 static int taprio_mqprio_cmp(const struct net_device *dev,
1797 const struct tc_mqprio_qopt *mqprio)
1798 {
1799 int i;
1800
1801 if (!mqprio || mqprio->num_tc != dev->num_tc)
1802 return -1;
1803
1804 for (i = 0; i < mqprio->num_tc; i++)
1805 if (dev->tc_to_txq[i].count != mqprio->count[i] ||
1806 dev->tc_to_txq[i].offset != mqprio->offset[i])
1807 return -1;
1808
1809 for (i = 0; i <= TC_BITMASK; i++)
1810 if (dev->prio_tc_map[i] != mqprio->prio_tc_map[i])
1811 return -1;
1812
1813 return 0;
1814 }
1815
1816 /* The semantics of the 'flags' argument in relation to 'change()'
1817 * requests, are interpreted following two rules (which are applied in
1818 * this order): (1) an omitted 'flags' argument is interpreted as
1819 * zero; (2) the 'flags' of a "running" taprio instance cannot be
1820 * changed.
1821 */
taprio_new_flags(const struct nlattr * attr,u32 old,struct netlink_ext_ack * extack)1822 static int taprio_new_flags(const struct nlattr *attr, u32 old,
1823 struct netlink_ext_ack *extack)
1824 {
1825 u32 new = 0;
1826
1827 if (attr)
1828 new = nla_get_u32(attr);
1829
1830 if (old != TAPRIO_FLAGS_INVALID && old != new) {
1831 NL_SET_ERR_MSG_MOD(extack, "Changing 'flags' of a running schedule is not supported");
1832 return -EOPNOTSUPP;
1833 }
1834
1835 if (!taprio_flags_valid(new)) {
1836 NL_SET_ERR_MSG_MOD(extack, "Specified 'flags' are not valid");
1837 return -EINVAL;
1838 }
1839
1840 return new;
1841 }
1842
taprio_change(struct Qdisc * sch,struct nlattr * opt,struct netlink_ext_ack * extack)1843 static int taprio_change(struct Qdisc *sch, struct nlattr *opt,
1844 struct netlink_ext_ack *extack)
1845 {
1846 struct qdisc_size_table *stab = rtnl_dereference(sch->stab);
1847 struct nlattr *tb[TCA_TAPRIO_ATTR_MAX + 1] = { };
1848 struct sched_gate_list *oper, *admin, *new_admin;
1849 struct taprio_sched *q = qdisc_priv(sch);
1850 struct net_device *dev = qdisc_dev(sch);
1851 struct tc_mqprio_qopt *mqprio = NULL;
1852 unsigned long flags;
1853 ktime_t start;
1854 int i, err;
1855
1856 err = nla_parse_nested_deprecated(tb, TCA_TAPRIO_ATTR_MAX, opt,
1857 taprio_policy, extack);
1858 if (err < 0)
1859 return err;
1860
1861 if (tb[TCA_TAPRIO_ATTR_PRIOMAP])
1862 mqprio = nla_data(tb[TCA_TAPRIO_ATTR_PRIOMAP]);
1863
1864 err = taprio_new_flags(tb[TCA_TAPRIO_ATTR_FLAGS],
1865 q->flags, extack);
1866 if (err < 0)
1867 return err;
1868
1869 q->flags = err;
1870
1871 /* Needed for length_to_duration() during netlink attribute parsing */
1872 taprio_set_picos_per_byte(dev, q);
1873
1874 err = taprio_parse_mqprio_opt(dev, mqprio, extack, q->flags);
1875 if (err < 0)
1876 return err;
1877
1878 err = taprio_parse_tc_entries(sch, opt, extack);
1879 if (err)
1880 return err;
1881
1882 new_admin = kzalloc(sizeof(*new_admin), GFP_KERNEL);
1883 if (!new_admin) {
1884 NL_SET_ERR_MSG(extack, "Not enough memory for a new schedule");
1885 return -ENOMEM;
1886 }
1887 INIT_LIST_HEAD(&new_admin->entries);
1888
1889 oper = rtnl_dereference(q->oper_sched);
1890 admin = rtnl_dereference(q->admin_sched);
1891
1892 /* no changes - no new mqprio settings */
1893 if (!taprio_mqprio_cmp(dev, mqprio))
1894 mqprio = NULL;
1895
1896 if (mqprio && (oper || admin)) {
1897 NL_SET_ERR_MSG(extack, "Changing the traffic mapping of a running schedule is not supported");
1898 err = -ENOTSUPP;
1899 goto free_sched;
1900 }
1901
1902 if (mqprio) {
1903 err = netdev_set_num_tc(dev, mqprio->num_tc);
1904 if (err)
1905 goto free_sched;
1906 for (i = 0; i < mqprio->num_tc; i++) {
1907 netdev_set_tc_queue(dev, i,
1908 mqprio->count[i],
1909 mqprio->offset[i]);
1910 q->cur_txq[i] = mqprio->offset[i];
1911 }
1912
1913 /* Always use supplied priority mappings */
1914 for (i = 0; i <= TC_BITMASK; i++)
1915 netdev_set_prio_tc_map(dev, i,
1916 mqprio->prio_tc_map[i]);
1917 }
1918
1919 err = parse_taprio_schedule(q, tb, new_admin, extack);
1920 if (err < 0)
1921 goto free_sched;
1922
1923 if (new_admin->num_entries == 0) {
1924 NL_SET_ERR_MSG(extack, "There should be at least one entry in the schedule");
1925 err = -EINVAL;
1926 goto free_sched;
1927 }
1928
1929 err = taprio_parse_clockid(sch, tb, extack);
1930 if (err < 0)
1931 goto free_sched;
1932
1933 taprio_update_queue_max_sdu(q, new_admin, stab);
1934
1935 if (FULL_OFFLOAD_IS_ENABLED(q->flags))
1936 err = taprio_enable_offload(dev, q, new_admin, extack);
1937 else
1938 err = taprio_disable_offload(dev, q, extack);
1939 if (err)
1940 goto free_sched;
1941
1942 /* Protects against enqueue()/dequeue() */
1943 spin_lock_bh(qdisc_lock(sch));
1944
1945 if (tb[TCA_TAPRIO_ATTR_TXTIME_DELAY]) {
1946 if (!TXTIME_ASSIST_IS_ENABLED(q->flags)) {
1947 NL_SET_ERR_MSG_MOD(extack, "txtime-delay can only be set when txtime-assist mode is enabled");
1948 err = -EINVAL;
1949 goto unlock;
1950 }
1951
1952 q->txtime_delay = nla_get_u32(tb[TCA_TAPRIO_ATTR_TXTIME_DELAY]);
1953 }
1954
1955 if (!TXTIME_ASSIST_IS_ENABLED(q->flags) &&
1956 !FULL_OFFLOAD_IS_ENABLED(q->flags) &&
1957 !hrtimer_active(&q->advance_timer)) {
1958 hrtimer_init(&q->advance_timer, q->clockid, HRTIMER_MODE_ABS);
1959 q->advance_timer.function = advance_sched;
1960 }
1961
1962 err = taprio_get_start_time(sch, new_admin, &start);
1963 if (err < 0) {
1964 NL_SET_ERR_MSG(extack, "Internal error: failed get start time");
1965 goto unlock;
1966 }
1967
1968 setup_txtime(q, new_admin, start);
1969
1970 if (TXTIME_ASSIST_IS_ENABLED(q->flags)) {
1971 if (!oper) {
1972 rcu_assign_pointer(q->oper_sched, new_admin);
1973 err = 0;
1974 new_admin = NULL;
1975 goto unlock;
1976 }
1977
1978 rcu_assign_pointer(q->admin_sched, new_admin);
1979 if (admin)
1980 call_rcu(&admin->rcu, taprio_free_sched_cb);
1981 } else {
1982 setup_first_end_time(q, new_admin, start);
1983
1984 /* Protects against advance_sched() */
1985 spin_lock_irqsave(&q->current_entry_lock, flags);
1986
1987 taprio_start_sched(sch, start, new_admin);
1988
1989 rcu_assign_pointer(q->admin_sched, new_admin);
1990 if (admin)
1991 call_rcu(&admin->rcu, taprio_free_sched_cb);
1992
1993 spin_unlock_irqrestore(&q->current_entry_lock, flags);
1994
1995 if (FULL_OFFLOAD_IS_ENABLED(q->flags))
1996 taprio_offload_config_changed(q);
1997 }
1998
1999 new_admin = NULL;
2000 err = 0;
2001
2002 if (!stab)
2003 NL_SET_ERR_MSG_MOD(extack,
2004 "Size table not specified, frame length estimations may be inaccurate");
2005
2006 unlock:
2007 spin_unlock_bh(qdisc_lock(sch));
2008
2009 free_sched:
2010 if (new_admin)
2011 call_rcu(&new_admin->rcu, taprio_free_sched_cb);
2012
2013 return err;
2014 }
2015
taprio_reset(struct Qdisc * sch)2016 static void taprio_reset(struct Qdisc *sch)
2017 {
2018 struct taprio_sched *q = qdisc_priv(sch);
2019 struct net_device *dev = qdisc_dev(sch);
2020 int i;
2021
2022 hrtimer_cancel(&q->advance_timer);
2023
2024 if (q->qdiscs) {
2025 for (i = 0; i < dev->num_tx_queues; i++)
2026 if (q->qdiscs[i])
2027 qdisc_reset(q->qdiscs[i]);
2028 }
2029 }
2030
taprio_destroy(struct Qdisc * sch)2031 static void taprio_destroy(struct Qdisc *sch)
2032 {
2033 struct taprio_sched *q = qdisc_priv(sch);
2034 struct net_device *dev = qdisc_dev(sch);
2035 struct sched_gate_list *oper, *admin;
2036 unsigned int i;
2037
2038 list_del(&q->taprio_list);
2039
2040 /* Note that taprio_reset() might not be called if an error
2041 * happens in qdisc_create(), after taprio_init() has been called.
2042 */
2043 hrtimer_cancel(&q->advance_timer);
2044 qdisc_synchronize(sch);
2045
2046 taprio_disable_offload(dev, q, NULL);
2047
2048 if (q->qdiscs) {
2049 for (i = 0; i < dev->num_tx_queues; i++)
2050 qdisc_put(q->qdiscs[i]);
2051
2052 kfree(q->qdiscs);
2053 }
2054 q->qdiscs = NULL;
2055
2056 netdev_reset_tc(dev);
2057
2058 oper = rtnl_dereference(q->oper_sched);
2059 admin = rtnl_dereference(q->admin_sched);
2060
2061 if (oper)
2062 call_rcu(&oper->rcu, taprio_free_sched_cb);
2063
2064 if (admin)
2065 call_rcu(&admin->rcu, taprio_free_sched_cb);
2066
2067 taprio_cleanup_broken_mqprio(q);
2068 }
2069
taprio_init(struct Qdisc * sch,struct nlattr * opt,struct netlink_ext_ack * extack)2070 static int taprio_init(struct Qdisc *sch, struct nlattr *opt,
2071 struct netlink_ext_ack *extack)
2072 {
2073 struct taprio_sched *q = qdisc_priv(sch);
2074 struct net_device *dev = qdisc_dev(sch);
2075 int i, tc;
2076
2077 spin_lock_init(&q->current_entry_lock);
2078
2079 hrtimer_init(&q->advance_timer, CLOCK_TAI, HRTIMER_MODE_ABS);
2080 q->advance_timer.function = advance_sched;
2081
2082 q->root = sch;
2083
2084 /* We only support static clockids. Use an invalid value as default
2085 * and get the valid one on taprio_change().
2086 */
2087 q->clockid = -1;
2088 q->flags = TAPRIO_FLAGS_INVALID;
2089
2090 list_add(&q->taprio_list, &taprio_list);
2091
2092 if (sch->parent != TC_H_ROOT) {
2093 NL_SET_ERR_MSG_MOD(extack, "Can only be attached as root qdisc");
2094 return -EOPNOTSUPP;
2095 }
2096
2097 if (!netif_is_multiqueue(dev)) {
2098 NL_SET_ERR_MSG_MOD(extack, "Multi-queue device is required");
2099 return -EOPNOTSUPP;
2100 }
2101
2102 q->qdiscs = kcalloc(dev->num_tx_queues, sizeof(q->qdiscs[0]),
2103 GFP_KERNEL);
2104 if (!q->qdiscs)
2105 return -ENOMEM;
2106
2107 if (!opt)
2108 return -EINVAL;
2109
2110 for (i = 0; i < dev->num_tx_queues; i++) {
2111 struct netdev_queue *dev_queue;
2112 struct Qdisc *qdisc;
2113
2114 dev_queue = netdev_get_tx_queue(dev, i);
2115 qdisc = qdisc_create_dflt(dev_queue,
2116 &pfifo_qdisc_ops,
2117 TC_H_MAKE(TC_H_MAJ(sch->handle),
2118 TC_H_MIN(i + 1)),
2119 extack);
2120 if (!qdisc)
2121 return -ENOMEM;
2122
2123 if (i < dev->real_num_tx_queues)
2124 qdisc_hash_add(qdisc, false);
2125
2126 q->qdiscs[i] = qdisc;
2127 }
2128
2129 for (tc = 0; tc < TC_QOPT_MAX_QUEUE; tc++)
2130 q->fp[tc] = TC_FP_EXPRESS;
2131
2132 taprio_detect_broken_mqprio(q);
2133
2134 return taprio_change(sch, opt, extack);
2135 }
2136
taprio_attach(struct Qdisc * sch)2137 static void taprio_attach(struct Qdisc *sch)
2138 {
2139 struct taprio_sched *q = qdisc_priv(sch);
2140 struct net_device *dev = qdisc_dev(sch);
2141 unsigned int ntx;
2142
2143 /* Attach underlying qdisc */
2144 for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
2145 struct netdev_queue *dev_queue = netdev_get_tx_queue(dev, ntx);
2146 struct Qdisc *old, *dev_queue_qdisc;
2147
2148 if (FULL_OFFLOAD_IS_ENABLED(q->flags)) {
2149 struct Qdisc *qdisc = q->qdiscs[ntx];
2150
2151 /* In offload mode, the root taprio qdisc is bypassed
2152 * and the netdev TX queues see the children directly
2153 */
2154 qdisc->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
2155 dev_queue_qdisc = qdisc;
2156 } else {
2157 /* In software mode, attach the root taprio qdisc
2158 * to all netdev TX queues, so that dev_qdisc_enqueue()
2159 * goes through taprio_enqueue().
2160 */
2161 dev_queue_qdisc = sch;
2162 }
2163 old = dev_graft_qdisc(dev_queue, dev_queue_qdisc);
2164 /* The qdisc's refcount requires to be elevated once
2165 * for each netdev TX queue it is grafted onto
2166 */
2167 qdisc_refcount_inc(dev_queue_qdisc);
2168 if (old)
2169 qdisc_put(old);
2170 }
2171 }
2172
taprio_queue_get(struct Qdisc * sch,unsigned long cl)2173 static struct netdev_queue *taprio_queue_get(struct Qdisc *sch,
2174 unsigned long cl)
2175 {
2176 struct net_device *dev = qdisc_dev(sch);
2177 unsigned long ntx = cl - 1;
2178
2179 if (ntx >= dev->num_tx_queues)
2180 return NULL;
2181
2182 return netdev_get_tx_queue(dev, ntx);
2183 }
2184
taprio_graft(struct Qdisc * sch,unsigned long cl,struct Qdisc * new,struct Qdisc ** old,struct netlink_ext_ack * extack)2185 static int taprio_graft(struct Qdisc *sch, unsigned long cl,
2186 struct Qdisc *new, struct Qdisc **old,
2187 struct netlink_ext_ack *extack)
2188 {
2189 struct taprio_sched *q = qdisc_priv(sch);
2190 struct net_device *dev = qdisc_dev(sch);
2191 struct netdev_queue *dev_queue = taprio_queue_get(sch, cl);
2192
2193 if (!dev_queue)
2194 return -EINVAL;
2195
2196 if (dev->flags & IFF_UP)
2197 dev_deactivate(dev);
2198
2199 /* In offload mode, the child Qdisc is directly attached to the netdev
2200 * TX queue, and thus, we need to keep its refcount elevated in order
2201 * to counteract qdisc_graft()'s call to qdisc_put() once per TX queue.
2202 * However, save the reference to the new qdisc in the private array in
2203 * both software and offload cases, to have an up-to-date reference to
2204 * our children.
2205 */
2206 *old = q->qdiscs[cl - 1];
2207 if (FULL_OFFLOAD_IS_ENABLED(q->flags)) {
2208 WARN_ON_ONCE(dev_graft_qdisc(dev_queue, new) != *old);
2209 if (new)
2210 qdisc_refcount_inc(new);
2211 if (*old)
2212 qdisc_put(*old);
2213 }
2214
2215 q->qdiscs[cl - 1] = new;
2216 if (new)
2217 new->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
2218
2219 if (dev->flags & IFF_UP)
2220 dev_activate(dev);
2221
2222 return 0;
2223 }
2224
dump_entry(struct sk_buff * msg,const struct sched_entry * entry)2225 static int dump_entry(struct sk_buff *msg,
2226 const struct sched_entry *entry)
2227 {
2228 struct nlattr *item;
2229
2230 item = nla_nest_start_noflag(msg, TCA_TAPRIO_SCHED_ENTRY);
2231 if (!item)
2232 return -ENOSPC;
2233
2234 if (nla_put_u32(msg, TCA_TAPRIO_SCHED_ENTRY_INDEX, entry->index))
2235 goto nla_put_failure;
2236
2237 if (nla_put_u8(msg, TCA_TAPRIO_SCHED_ENTRY_CMD, entry->command))
2238 goto nla_put_failure;
2239
2240 if (nla_put_u32(msg, TCA_TAPRIO_SCHED_ENTRY_GATE_MASK,
2241 entry->gate_mask))
2242 goto nla_put_failure;
2243
2244 if (nla_put_u32(msg, TCA_TAPRIO_SCHED_ENTRY_INTERVAL,
2245 entry->interval))
2246 goto nla_put_failure;
2247
2248 return nla_nest_end(msg, item);
2249
2250 nla_put_failure:
2251 nla_nest_cancel(msg, item);
2252 return -1;
2253 }
2254
dump_schedule(struct sk_buff * msg,const struct sched_gate_list * root)2255 static int dump_schedule(struct sk_buff *msg,
2256 const struct sched_gate_list *root)
2257 {
2258 struct nlattr *entry_list;
2259 struct sched_entry *entry;
2260
2261 if (nla_put_s64(msg, TCA_TAPRIO_ATTR_SCHED_BASE_TIME,
2262 root->base_time, TCA_TAPRIO_PAD))
2263 return -1;
2264
2265 if (nla_put_s64(msg, TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME,
2266 root->cycle_time, TCA_TAPRIO_PAD))
2267 return -1;
2268
2269 if (nla_put_s64(msg, TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME_EXTENSION,
2270 root->cycle_time_extension, TCA_TAPRIO_PAD))
2271 return -1;
2272
2273 entry_list = nla_nest_start_noflag(msg,
2274 TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST);
2275 if (!entry_list)
2276 goto error_nest;
2277
2278 list_for_each_entry(entry, &root->entries, list) {
2279 if (dump_entry(msg, entry) < 0)
2280 goto error_nest;
2281 }
2282
2283 nla_nest_end(msg, entry_list);
2284 return 0;
2285
2286 error_nest:
2287 nla_nest_cancel(msg, entry_list);
2288 return -1;
2289 }
2290
taprio_dump_tc_entries(struct sk_buff * skb,struct taprio_sched * q,struct sched_gate_list * sched)2291 static int taprio_dump_tc_entries(struct sk_buff *skb,
2292 struct taprio_sched *q,
2293 struct sched_gate_list *sched)
2294 {
2295 struct nlattr *n;
2296 int tc;
2297
2298 for (tc = 0; tc < TC_MAX_QUEUE; tc++) {
2299 n = nla_nest_start(skb, TCA_TAPRIO_ATTR_TC_ENTRY);
2300 if (!n)
2301 return -EMSGSIZE;
2302
2303 if (nla_put_u32(skb, TCA_TAPRIO_TC_ENTRY_INDEX, tc))
2304 goto nla_put_failure;
2305
2306 if (nla_put_u32(skb, TCA_TAPRIO_TC_ENTRY_MAX_SDU,
2307 sched->max_sdu[tc]))
2308 goto nla_put_failure;
2309
2310 if (nla_put_u32(skb, TCA_TAPRIO_TC_ENTRY_FP, q->fp[tc]))
2311 goto nla_put_failure;
2312
2313 nla_nest_end(skb, n);
2314 }
2315
2316 return 0;
2317
2318 nla_put_failure:
2319 nla_nest_cancel(skb, n);
2320 return -EMSGSIZE;
2321 }
2322
taprio_put_stat(struct sk_buff * skb,u64 val,u16 attrtype)2323 static int taprio_put_stat(struct sk_buff *skb, u64 val, u16 attrtype)
2324 {
2325 if (val == TAPRIO_STAT_NOT_SET)
2326 return 0;
2327 if (nla_put_u64_64bit(skb, attrtype, val, TCA_TAPRIO_OFFLOAD_STATS_PAD))
2328 return -EMSGSIZE;
2329 return 0;
2330 }
2331
taprio_dump_xstats(struct Qdisc * sch,struct gnet_dump * d,struct tc_taprio_qopt_offload * offload,struct tc_taprio_qopt_stats * stats)2332 static int taprio_dump_xstats(struct Qdisc *sch, struct gnet_dump *d,
2333 struct tc_taprio_qopt_offload *offload,
2334 struct tc_taprio_qopt_stats *stats)
2335 {
2336 struct net_device *dev = qdisc_dev(sch);
2337 const struct net_device_ops *ops;
2338 struct sk_buff *skb = d->skb;
2339 struct nlattr *xstats;
2340 int err;
2341
2342 ops = qdisc_dev(sch)->netdev_ops;
2343
2344 /* FIXME I could use qdisc_offload_dump_helper(), but that messes
2345 * with sch->flags depending on whether the device reports taprio
2346 * stats, and I'm not sure whether that's a good idea, considering
2347 * that stats are optional to the offload itself
2348 */
2349 if (!ops->ndo_setup_tc)
2350 return 0;
2351
2352 memset(stats, 0xff, sizeof(*stats));
2353
2354 err = ops->ndo_setup_tc(dev, TC_SETUP_QDISC_TAPRIO, offload);
2355 if (err == -EOPNOTSUPP)
2356 return 0;
2357 if (err)
2358 return err;
2359
2360 xstats = nla_nest_start(skb, TCA_STATS_APP);
2361 if (!xstats)
2362 goto err;
2363
2364 if (taprio_put_stat(skb, stats->window_drops,
2365 TCA_TAPRIO_OFFLOAD_STATS_WINDOW_DROPS) ||
2366 taprio_put_stat(skb, stats->tx_overruns,
2367 TCA_TAPRIO_OFFLOAD_STATS_TX_OVERRUNS))
2368 goto err_cancel;
2369
2370 nla_nest_end(skb, xstats);
2371
2372 return 0;
2373
2374 err_cancel:
2375 nla_nest_cancel(skb, xstats);
2376 err:
2377 return -EMSGSIZE;
2378 }
2379
taprio_dump_stats(struct Qdisc * sch,struct gnet_dump * d)2380 static int taprio_dump_stats(struct Qdisc *sch, struct gnet_dump *d)
2381 {
2382 struct tc_taprio_qopt_offload offload = {
2383 .cmd = TAPRIO_CMD_STATS,
2384 };
2385
2386 return taprio_dump_xstats(sch, d, &offload, &offload.stats);
2387 }
2388
taprio_dump(struct Qdisc * sch,struct sk_buff * skb)2389 static int taprio_dump(struct Qdisc *sch, struct sk_buff *skb)
2390 {
2391 struct taprio_sched *q = qdisc_priv(sch);
2392 struct net_device *dev = qdisc_dev(sch);
2393 struct sched_gate_list *oper, *admin;
2394 struct tc_mqprio_qopt opt = { 0 };
2395 struct nlattr *nest, *sched_nest;
2396
2397 oper = rtnl_dereference(q->oper_sched);
2398 admin = rtnl_dereference(q->admin_sched);
2399
2400 mqprio_qopt_reconstruct(dev, &opt);
2401
2402 nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
2403 if (!nest)
2404 goto start_error;
2405
2406 if (nla_put(skb, TCA_TAPRIO_ATTR_PRIOMAP, sizeof(opt), &opt))
2407 goto options_error;
2408
2409 if (!FULL_OFFLOAD_IS_ENABLED(q->flags) &&
2410 nla_put_s32(skb, TCA_TAPRIO_ATTR_SCHED_CLOCKID, q->clockid))
2411 goto options_error;
2412
2413 if (q->flags && nla_put_u32(skb, TCA_TAPRIO_ATTR_FLAGS, q->flags))
2414 goto options_error;
2415
2416 if (q->txtime_delay &&
2417 nla_put_u32(skb, TCA_TAPRIO_ATTR_TXTIME_DELAY, q->txtime_delay))
2418 goto options_error;
2419
2420 if (oper && taprio_dump_tc_entries(skb, q, oper))
2421 goto options_error;
2422
2423 if (oper && dump_schedule(skb, oper))
2424 goto options_error;
2425
2426 if (!admin)
2427 goto done;
2428
2429 sched_nest = nla_nest_start_noflag(skb, TCA_TAPRIO_ATTR_ADMIN_SCHED);
2430 if (!sched_nest)
2431 goto options_error;
2432
2433 if (dump_schedule(skb, admin))
2434 goto admin_error;
2435
2436 nla_nest_end(skb, sched_nest);
2437
2438 done:
2439 return nla_nest_end(skb, nest);
2440
2441 admin_error:
2442 nla_nest_cancel(skb, sched_nest);
2443
2444 options_error:
2445 nla_nest_cancel(skb, nest);
2446
2447 start_error:
2448 return -ENOSPC;
2449 }
2450
taprio_leaf(struct Qdisc * sch,unsigned long cl)2451 static struct Qdisc *taprio_leaf(struct Qdisc *sch, unsigned long cl)
2452 {
2453 struct taprio_sched *q = qdisc_priv(sch);
2454 struct net_device *dev = qdisc_dev(sch);
2455 unsigned int ntx = cl - 1;
2456
2457 if (ntx >= dev->num_tx_queues)
2458 return NULL;
2459
2460 return q->qdiscs[ntx];
2461 }
2462
taprio_find(struct Qdisc * sch,u32 classid)2463 static unsigned long taprio_find(struct Qdisc *sch, u32 classid)
2464 {
2465 unsigned int ntx = TC_H_MIN(classid);
2466
2467 if (!taprio_queue_get(sch, ntx))
2468 return 0;
2469 return ntx;
2470 }
2471
taprio_dump_class(struct Qdisc * sch,unsigned long cl,struct sk_buff * skb,struct tcmsg * tcm)2472 static int taprio_dump_class(struct Qdisc *sch, unsigned long cl,
2473 struct sk_buff *skb, struct tcmsg *tcm)
2474 {
2475 struct Qdisc *child = taprio_leaf(sch, cl);
2476
2477 tcm->tcm_parent = TC_H_ROOT;
2478 tcm->tcm_handle |= TC_H_MIN(cl);
2479 tcm->tcm_info = child->handle;
2480
2481 return 0;
2482 }
2483
taprio_dump_class_stats(struct Qdisc * sch,unsigned long cl,struct gnet_dump * d)2484 static int taprio_dump_class_stats(struct Qdisc *sch, unsigned long cl,
2485 struct gnet_dump *d)
2486 __releases(d->lock)
2487 __acquires(d->lock)
2488 {
2489 struct Qdisc *child = taprio_leaf(sch, cl);
2490 struct tc_taprio_qopt_offload offload = {
2491 .cmd = TAPRIO_CMD_QUEUE_STATS,
2492 .queue_stats = {
2493 .queue = cl - 1,
2494 },
2495 };
2496
2497 if (gnet_stats_copy_basic(d, NULL, &child->bstats, true) < 0 ||
2498 qdisc_qstats_copy(d, child) < 0)
2499 return -1;
2500
2501 return taprio_dump_xstats(sch, d, &offload, &offload.queue_stats.stats);
2502 }
2503
taprio_walk(struct Qdisc * sch,struct qdisc_walker * arg)2504 static void taprio_walk(struct Qdisc *sch, struct qdisc_walker *arg)
2505 {
2506 struct net_device *dev = qdisc_dev(sch);
2507 unsigned long ntx;
2508
2509 if (arg->stop)
2510 return;
2511
2512 arg->count = arg->skip;
2513 for (ntx = arg->skip; ntx < dev->num_tx_queues; ntx++) {
2514 if (!tc_qdisc_stats_dump(sch, ntx + 1, arg))
2515 break;
2516 }
2517 }
2518
taprio_select_queue(struct Qdisc * sch,struct tcmsg * tcm)2519 static struct netdev_queue *taprio_select_queue(struct Qdisc *sch,
2520 struct tcmsg *tcm)
2521 {
2522 return taprio_queue_get(sch, TC_H_MIN(tcm->tcm_parent));
2523 }
2524
2525 static const struct Qdisc_class_ops taprio_class_ops = {
2526 .graft = taprio_graft,
2527 .leaf = taprio_leaf,
2528 .find = taprio_find,
2529 .walk = taprio_walk,
2530 .dump = taprio_dump_class,
2531 .dump_stats = taprio_dump_class_stats,
2532 .select_queue = taprio_select_queue,
2533 };
2534
2535 static struct Qdisc_ops taprio_qdisc_ops __read_mostly = {
2536 .cl_ops = &taprio_class_ops,
2537 .id = "taprio",
2538 .priv_size = sizeof(struct taprio_sched),
2539 .init = taprio_init,
2540 .change = taprio_change,
2541 .destroy = taprio_destroy,
2542 .reset = taprio_reset,
2543 .attach = taprio_attach,
2544 .peek = taprio_peek,
2545 .dequeue = taprio_dequeue,
2546 .enqueue = taprio_enqueue,
2547 .dump = taprio_dump,
2548 .dump_stats = taprio_dump_stats,
2549 .owner = THIS_MODULE,
2550 };
2551
2552 static struct notifier_block taprio_device_notifier = {
2553 .notifier_call = taprio_dev_notifier,
2554 };
2555
taprio_module_init(void)2556 static int __init taprio_module_init(void)
2557 {
2558 int err = register_netdevice_notifier(&taprio_device_notifier);
2559
2560 if (err)
2561 return err;
2562
2563 return register_qdisc(&taprio_qdisc_ops);
2564 }
2565
taprio_module_exit(void)2566 static void __exit taprio_module_exit(void)
2567 {
2568 unregister_qdisc(&taprio_qdisc_ops);
2569 unregister_netdevice_notifier(&taprio_device_notifier);
2570 }
2571
2572 module_init(taprio_module_init);
2573 module_exit(taprio_module_exit);
2574 MODULE_LICENSE("GPL");
2575