summaryrefslogtreecommitdiffstats
path: root/drivers/net/ethernet/mellanox/mlx5/core/en/htb.c
blob: 09d441ecb9f6d204e236f7e340e174a0842349bb (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
/* Copyright (c) 2022, NVIDIA CORPORATION & AFFILIATES. All rights reserved. */

#include <net/pkt_cls.h>
#include "htb.h"
#include "en.h"
#include "../qos.h"

struct mlx5e_qos_node {
	struct hlist_node hnode;
	struct mlx5e_qos_node *parent;
	u64 rate;
	u32 bw_share;
	u32 max_average_bw;
	u32 hw_id;
	u32 classid; /* 16-bit, except root. */
	u16 qid;
};

struct mlx5e_htb {
	DECLARE_HASHTABLE(qos_tc2node, order_base_2(MLX5E_QOS_MAX_LEAF_NODES));
	DECLARE_BITMAP(qos_used_qids, MLX5E_QOS_MAX_LEAF_NODES);
	struct mlx5_core_dev *mdev;
	struct net_device *netdev;
	struct mlx5e_priv *priv;
	struct mlx5e_selq *selq;
};

#define MLX5E_QOS_QID_INNER 0xffff
#define MLX5E_HTB_CLASSID_ROOT 0xffffffff

/* Software representation of the QoS tree */

int mlx5e_htb_enumerate_leaves(struct mlx5e_htb *htb, mlx5e_fp_htb_enumerate callback, void *data)
{
	struct mlx5e_qos_node *node = NULL;
	int bkt, err;

	hash_for_each(htb->qos_tc2node, bkt, node, hnode) {
		if (node->qid == MLX5E_QOS_QID_INNER)
			continue;
		err = callback(data, node->qid, node->hw_id);
		if (err)
			return err;
	}
	return 0;
}

int mlx5e_htb_cur_leaf_nodes(struct mlx5e_htb *htb)
{
	int last;

	last = find_last_bit(htb->qos_used_qids, mlx5e_qos_max_leaf_nodes(htb->mdev));
	return last == mlx5e_qos_max_leaf_nodes(htb->mdev) ? 0 : last + 1;
}

static int mlx5e_htb_find_unused_qos_qid(struct mlx5e_htb *htb)
{
	int size = mlx5e_qos_max_leaf_nodes(htb->mdev);
	struct mlx5e_priv *priv = htb->priv;
	int res;

	WARN_ONCE(!mutex_is_locked(&priv->state_lock), "%s: state_lock is not held\n", __func__);
	res = find_first_zero_bit(htb->qos_used_qids, size);

	return res == size ? -ENOSPC : res;
}

static struct mlx5e_qos_node *
mlx5e_htb_node_create_leaf(struct mlx5e_htb *htb, u16 classid, u16 qid,
			   struct mlx5e_qos_node *parent)
{
	struct mlx5e_qos_node *node;

	node = kzalloc(sizeof(*node), GFP_KERNEL);
	if (!node)
		return ERR_PTR(-ENOMEM);

	node->parent = parent;

	node->qid = qid;
	__set_bit(qid, htb->qos_used_qids);

	node->classid = classid;
	hash_add_rcu(htb->qos_tc2node, &node->hnode, classid);

	mlx5e_update_tx_netdev_queues(htb->priv);

	return node;
}

static struct mlx5e_qos_node *mlx5e_htb_node_create_root(struct mlx5e_htb *htb)
{
	struct mlx5e_qos_node *node;

	node = kzalloc(sizeof(*node), GFP_KERNEL);
	if (!node)
		return ERR_PTR(-ENOMEM);

	node->qid = MLX5E_QOS_QID_INNER;
	node->classid = MLX5E_HTB_CLASSID_ROOT;
	hash_add_rcu(htb->qos_tc2node, &node->hnode, node->classid);

	return node;
}

static struct mlx5e_qos_node *mlx5e_htb_node_find(struct mlx5e_htb *htb, u32 classid)
{
	struct mlx5e_qos_node *node = NULL;

	hash_for_each_possible(htb->qos_tc2node, node, hnode, classid) {
		if (node->classid == classid)
			break;
	}

	return node;
}

static struct mlx5e_qos_node *mlx5e_htb_node_find_rcu(struct mlx5e_htb *htb, u32 classid)
{
	struct mlx5e_qos_node *node = NULL;

	hash_for_each_possible_rcu(htb->qos_tc2node, node, hnode, classid) {
		if (node->classid == classid)
			break;
	}

	return node;
}

static void mlx5e_htb_node_delete(struct mlx5e_htb *htb, struct mlx5e_qos_node *node)
{
	hash_del_rcu(&node->hnode);
	if (node->qid != MLX5E_QOS_QID_INNER) {
		__clear_bit(node->qid, htb->qos_used_qids);
		mlx5e_update_tx_netdev_queues(htb->priv);
	}
	/* Make sure this qid is no longer selected by mlx5e_select_queue, so
	 * that mlx5e_reactivate_qos_sq can safely restart the netdev TX queue.
	 */
	synchronize_net();
	kfree(node);
}

/* TX datapath API */

int mlx5e_htb_get_txq_by_classid(struct mlx5e_htb *htb, u16 classid)
{
	struct mlx5e_qos_node *node;
	u16 qid;
	int res;

	rcu_read_lock();

	node = mlx5e_htb_node_find_rcu(htb, classid);
	if (!node) {
		res = -ENOENT;
		goto out;
	}
	qid = READ_ONCE(node->qid);
	if (qid == MLX5E_QOS_QID_INNER) {
		res = -EINVAL;
		goto out;
	}
	res = mlx5e_qid_from_qos(&htb->priv->channels, qid);

out:
	rcu_read_unlock();
	return res;
}

/* HTB TC handlers */

static int
mlx5e_htb_root_add(struct mlx5e_htb *htb, u16 htb_maj_id, u16 htb_defcls,
		   struct netlink_ext_ack *extack)
{
	struct mlx5e_priv *priv = htb->priv;
	struct mlx5e_qos_node *root;
	bool opened;
	int err;

	qos_dbg(htb->mdev, "TC_HTB_CREATE handle %04x:, default :%04x\n", htb_maj_id, htb_defcls);

	mlx5e_selq_prepare_htb(htb->selq, htb_maj_id, htb_defcls);

	opened = test_bit(MLX5E_STATE_OPENED, &priv->state);
	if (opened) {
		err = mlx5e_qos_alloc_queues(priv, &priv->channels);
		if (err)
			goto err_cancel_selq;
	}

	root = mlx5e_htb_node_create_root(htb);
	if (IS_ERR(root)) {
		err = PTR_ERR(root);
		goto err_free_queues;
	}

	err = mlx5_qos_create_root_node(htb->mdev, &root->hw_id);
	if (err) {
		NL_SET_ERR_MSG_MOD(extack, "Firmware error. Try upgrading firmware.");
		goto err_sw_node_delete;
	}

	mlx5e_selq_apply(htb->selq);

	return 0;

err_sw_node_delete:
	mlx5e_htb_node_delete(htb, root);

err_free_queues:
	if (opened)
		mlx5e_qos_close_all_queues(&priv->channels);
err_cancel_selq:
	mlx5e_selq_cancel(htb->selq);
	return err;
}

static int mlx5e_htb_root_del(struct mlx5e_htb *htb)
{
	struct mlx5e_priv *priv = htb->priv;
	struct mlx5e_qos_node *root;
	int err;

	qos_dbg(htb->mdev, "TC_HTB_DESTROY\n");

	/* Wait until real_num_tx_queues is updated for mlx5e_select_queue,
	 * so that we can safely switch to its non-HTB non-PTP fastpath.
	 */
	synchronize_net();

	mlx5e_selq_prepare_htb(htb->selq, 0, 0);
	mlx5e_selq_apply(htb->selq);

	root = mlx5e_htb_node_find(htb, MLX5E_HTB_CLASSID_ROOT);
	if (!root) {
		qos_err(htb->mdev, "Failed to find the root node in the QoS tree\n");
		return -ENOENT;
	}
	err = mlx5_qos_destroy_node(htb->mdev, root->hw_id);
	if (err)
		qos_err(htb->mdev, "Failed to destroy root node %u, err = %d\n",
			root->hw_id, err);
	mlx5e_htb_node_delete(htb, root);

	mlx5e_qos_deactivate_all_queues(&priv->channels);
	mlx5e_qos_close_all_queues(&priv->channels);

	return err;
}

static int mlx5e_htb_convert_rate(struct mlx5e_htb *htb, u64 rate,
				  struct mlx5e_qos_node *parent, u32 *bw_share)
{
	u64 share = 0;

	while (parent->classid != MLX5E_HTB_CLASSID_ROOT && !parent->max_average_bw)
		parent = parent->parent;

	if (parent->max_average_bw)
		share = div64_u64(div_u64(rate * 100, BYTES_IN_MBIT),
				  parent->max_average_bw);
	else
		share = 101;

	*bw_share = share == 0 ? 1 : share > 100 ? 0 : share;

	qos_dbg(htb->mdev, "Convert: rate %llu, parent ceil %llu -> bw_share %u\n",
		rate, (u64)parent->max_average_bw * BYTES_IN_MBIT, *bw_share);

	return 0;
}

static void mlx5e_htb_convert_ceil(struct mlx5e_htb *htb, u64 ceil, u32 *max_average_bw)
{
	/* Hardware treats 0 as "unlimited", set at least 1. */
	*max_average_bw = max_t(u32, div_u64(ceil, BYTES_IN_MBIT), 1);

	qos_dbg(htb->mdev, "Convert: ceil %llu -> max_average_bw %u\n",
		ceil, *max_average_bw);
}

int
mlx5e_htb_leaf_alloc_queue(struct mlx5e_htb *htb, u16 classid,
			   u32 parent_classid, u64 rate, u64 ceil,
			   struct netlink_ext_ack *extack)
{
	struct mlx5e_qos_node *node, *parent;
	struct mlx5e_priv *priv = htb->priv;
	int qid;
	int err;

	qos_dbg(htb->mdev, "TC_HTB_LEAF_ALLOC_QUEUE classid %04x, parent %04x, rate %llu, ceil %llu\n",
		classid, parent_classid, rate, ceil);

	qid = mlx5e_htb_find_unused_qos_qid(htb);
	if (qid < 0) {
		NL_SET_ERR_MSG_MOD(extack, "Maximum amount of leaf classes is reached.");
		return qid;
	}

	parent = mlx5e_htb_node_find(htb, parent_classid);
	if (!parent)
		return -EINVAL;

	node = mlx5e_htb_node_create_leaf(htb, classid, qid, parent);
	if (IS_ERR(node))
		return PTR_ERR(node);

	node->rate = rate;
	mlx5e_htb_convert_rate(htb, rate, node->parent, &node->bw_share);
	mlx5e_htb_convert_ceil(htb, ceil, &node->max_average_bw);

	err = mlx5_qos_create_leaf_node(htb->mdev, node->parent->hw_id,
					node->bw_share, node->max_average_bw,
					&node->hw_id);
	if (err) {
		NL_SET_ERR_MSG_MOD(extack, "Firmware error when creating a leaf node.");
		qos_err(htb->mdev, "Failed to create a leaf node (class %04x), err = %d\n",
			classid, err);
		mlx5e_htb_node_delete(htb, node);
		return err;
	}

	if (test_bit(MLX5E_STATE_OPENED, &priv->state)) {
		err = mlx5e_open_qos_sq(priv, &priv->channels, node->qid, node->hw_id);
		if (err) {
			NL_SET_ERR_MSG_MOD(extack, "Error creating an SQ.");
			qos_warn(htb->mdev, "Failed to create a QoS SQ (class %04x), err = %d\n",
				 classid, err);
		} else {
			mlx5e_activate_qos_sq(priv, node->qid, node->hw_id);
		}
	}

	return mlx5e_qid_from_qos(&priv->channels, node->qid);
}

int
mlx5e_htb_leaf_to_inner(struct mlx5e_htb *htb, u16 classid, u16 child_classid,
			u64 rate, u64 ceil, struct netlink_ext_ack *extack)
{
	struct mlx5e_qos_node *node, *child;
	struct mlx5e_priv *priv = htb->priv;
	int err, tmp_err;
	u32 new_hw_id;
	u16 qid;

	qos_dbg(htb->mdev, "TC_HTB_LEAF_TO_INNER classid %04x, upcoming child %04x, rate %llu, ceil %llu\n",
		classid, child_classid, rate, ceil);

	node = mlx5e_htb_node_find(htb, classid);
	if (!node)
		return -ENOENT;

	err = mlx5_qos_create_inner_node(htb->mdev, node->parent->hw_id,
					 node->bw_share, node->max_average_bw,
					 &new_hw_id);
	if (err) {
		NL_SET_ERR_MSG_MOD(extack, "Firmware error when creating an inner node.");
		qos_err(htb->mdev, "Failed to create an inner node (class %04x), err = %d\n",
			classid, err);
		return err;
	}

	/* Intentionally reuse the qid for the upcoming first child. */
	child = mlx5e_htb_node_create_leaf(htb, child_classid, node->qid, node);
	if (IS_ERR(child)) {
		err = PTR_ERR(child);
		goto err_destroy_hw_node;
	}

	child->rate = rate;
	mlx5e_htb_convert_rate(htb, rate, node, &child->bw_share);
	mlx5e_htb_convert_ceil(htb, ceil, &child->max_average_bw);

	err = mlx5_qos_create_leaf_node(htb->mdev, new_hw_id, child->bw_share,
					child->max_average_bw, &child->hw_id);
	if (err) {
		NL_SET_ERR_MSG_MOD(extack, "Firmware error when creating a leaf node.");
		qos_err(htb->mdev, "Failed to create a leaf node (class %04x), err = %d\n",
			classid, err);
		goto err_delete_sw_node;
	}

	/* No fail point. */

	qid = node->qid;
	/* Pairs with mlx5e_htb_get_txq_by_classid. */
	WRITE_ONCE(node->qid, MLX5E_QOS_QID_INNER);

	if (test_bit(MLX5E_STATE_OPENED, &priv->state)) {
		mlx5e_deactivate_qos_sq(priv, qid);
		mlx5e_close_qos_sq(priv, qid);
	}

	err = mlx5_qos_destroy_node(htb->mdev, node->hw_id);
	if (err) /* Not fatal. */
		qos_warn(htb->mdev, "Failed to destroy leaf node %u (class %04x), err = %d\n",
			 node->hw_id, classid, err);

	node->hw_id = new_hw_id;

	if (test_bit(MLX5E_STATE_OPENED, &priv->state)) {
		err = mlx5e_open_qos_sq(priv, &priv->channels, child->qid, child->hw_id);
		if (err) {
			NL_SET_ERR_MSG_MOD(extack, "Error creating an SQ.");
			qos_warn(htb->mdev, "Failed to create a QoS SQ (class %04x), err = %d\n",
				 classid, err);
		} else {
			mlx5e_activate_qos_sq(priv, child->qid, child->hw_id);
		}
	}

	return 0;

err_delete_sw_node:
	child->qid = MLX5E_QOS_QID_INNER;
	mlx5e_htb_node_delete(htb, child);

err_destroy_hw_node:
	tmp_err = mlx5_qos_destroy_node(htb->mdev, new_hw_id);
	if (tmp_err) /* Not fatal. */
		qos_warn(htb->mdev, "Failed to roll back creation of an inner node %u (class %04x), err = %d\n",
			 new_hw_id, classid, tmp_err);
	return err;
}

static struct mlx5e_qos_node *mlx5e_htb_node_find_by_qid(struct mlx5e_htb *htb, u16 qid)
{
	struct mlx5e_qos_node *node = NULL;
	int bkt;

	hash_for_each(htb->qos_tc2node, bkt, node, hnode)
		if (node->qid == qid)
			break;

	return node;
}

int mlx5e_htb_leaf_del(struct mlx5e_htb *htb, u16 *classid,
		       struct netlink_ext_ack *extack)
{
	struct mlx5e_priv *priv = htb->priv;
	struct mlx5e_qos_node *node;
	struct netdev_queue *txq;
	u16 qid, moved_qid;
	bool opened;
	int err;

	qos_dbg(htb->mdev, "TC_HTB_LEAF_DEL classid %04x\n", *classid);

	node = mlx5e_htb_node_find(htb, *classid);
	if (!node)
		return -ENOENT;

	/* Store qid for reuse. */
	qid = node->qid;

	opened = test_bit(MLX5E_STATE_OPENED, &priv->state);
	if (opened) {
		txq = netdev_get_tx_queue(htb->netdev,
					  mlx5e_qid_from_qos(&priv->channels, qid));
		mlx5e_deactivate_qos_sq(priv, qid);
		mlx5e_close_qos_sq(priv, qid);
	}

	err = mlx5_qos_destroy_node(htb->mdev, node->hw_id);
	if (err) /* Not fatal. */
		qos_warn(htb->mdev, "Failed to destroy leaf node %u (class %04x), err = %d\n",
			 node->hw_id, *classid, err);

	mlx5e_htb_node_delete(htb, node);

	moved_qid = mlx5e_htb_cur_leaf_nodes(htb);

	if (moved_qid == 0) {
		/* The last QoS SQ was just destroyed. */
		if (opened)
			mlx5e_reactivate_qos_sq(priv, qid, txq);
		return 0;
	}
	moved_qid--;

	if (moved_qid < qid) {
		/* The highest QoS SQ was just destroyed. */
		WARN(moved_qid != qid - 1, "Gaps in queue numeration: destroyed queue %u, the highest queue is %u",
		     qid, moved_qid);
		if (opened)
			mlx5e_reactivate_qos_sq(priv, qid, txq);
		return 0;
	}

	WARN(moved_qid == qid, "Can't move node with qid %u to itself", qid);
	qos_dbg(htb->mdev, "Moving QoS SQ %u to %u\n", moved_qid, qid);

	node = mlx5e_htb_node_find_by_qid(htb, moved_qid);
	WARN(!node, "Could not find a node with qid %u to move to queue %u",
	     moved_qid, qid);

	/* Stop traffic to the old queue. */
	WRITE_ONCE(node->qid, MLX5E_QOS_QID_INNER);
	__clear_bit(moved_qid, priv->htb->qos_used_qids);

	if (opened) {
		txq = netdev_get_tx_queue(htb->netdev,
					  mlx5e_qid_from_qos(&priv->channels, moved_qid));
		mlx5e_deactivate_qos_sq(priv, moved_qid);
		mlx5e_close_qos_sq(priv, moved_qid);
	}

	/* Prevent packets from the old class from getting into the new one. */
	mlx5e_reset_qdisc(htb->netdev, moved_qid);

	__set_bit(qid, htb->qos_used_qids);
	WRITE_ONCE(node->qid, qid);

	if (test_bit(MLX5E_STATE_OPENED, &priv->state)) {
		err = mlx5e_open_qos_sq(priv, &priv->channels, node->qid, node->hw_id);
		if (err) {
			NL_SET_ERR_MSG_MOD(extack, "Error creating an SQ.");
			qos_warn(htb->mdev, "Failed to create a QoS SQ (class %04x) while moving qid %u to %u, err = %d\n",
				 node->classid, moved_qid, qid, err);
		} else {
			mlx5e_activate_qos_sq(priv, node->qid, node->hw_id);
		}
	}

	mlx5e_update_tx_netdev_queues(priv);
	if (opened)
		mlx5e_reactivate_qos_sq(priv, moved_qid, txq);

	*classid = node->classid;
	return 0;
}

int
mlx5e_htb_leaf_del_last(struct mlx5e_htb *htb, u16 classid, bool force,
			struct netlink_ext_ack *extack)
{
	struct mlx5e_qos_node *node, *parent;
	struct mlx5e_priv *priv = htb->priv;
	u32 old_hw_id, new_hw_id;
	int err, saved_err = 0;
	u16 qid;

	qos_dbg(htb->mdev, "TC_HTB_LEAF_DEL_LAST%s classid %04x\n",
		force ? "_FORCE" : "", classid);

	node = mlx5e_htb_node_find(htb, classid);
	if (!node)
		return -ENOENT;

	err = mlx5_qos_create_leaf_node(htb->mdev, node->parent->parent->hw_id,
					node->parent->bw_share,
					node->parent->max_average_bw,
					&new_hw_id);
	if (err) {
		NL_SET_ERR_MSG_MOD(extack, "Firmware error when creating a leaf node.");
		qos_err(htb->mdev, "Failed to create a leaf node (class %04x), err = %d\n",
			classid, err);
		if (!force)
			return err;
		saved_err = err;
	}

	/* Store qid for reuse and prevent clearing the bit. */
	qid = node->qid;
	/* Pairs with mlx5e_htb_get_txq_by_classid. */
	WRITE_ONCE(node->qid, MLX5E_QOS_QID_INNER);

	if (test_bit(MLX5E_STATE_OPENED, &priv->state)) {
		mlx5e_deactivate_qos_sq(priv, qid);
		mlx5e_close_qos_sq(priv, qid);
	}

	/* Prevent packets from the old class from getting into the new one. */
	mlx5e_reset_qdisc(htb->netdev, qid);

	err = mlx5_qos_destroy_node(htb->mdev, node->hw_id);
	if (err) /* Not fatal. */
		qos_warn(htb->mdev, "Failed to destroy leaf node %u (class %04x), err = %d\n",
			 node->hw_id, classid, err);

	parent = node->parent;
	mlx5e_htb_node_delete(htb, node);

	node = parent;
	WRITE_ONCE(node->qid, qid);

	/* Early return on error in force mode. Parent will still be an inner
	 * node to be deleted by a following delete operation.
	 */
	if (saved_err)
		return saved_err;

	old_hw_id = node->hw_id;
	node->hw_id = new_hw_id;

	if (test_bit(MLX5E_STATE_OPENED, &priv->state)) {
		err = mlx5e_open_qos_sq(priv, &priv->channels, node->qid, node->hw_id);
		if (err) {
			NL_SET_ERR_MSG_MOD(extack, "Error creating an SQ.");
			qos_warn(htb->mdev, "Failed to create a QoS SQ (class %04x), err = %d\n",
				 classid, err);
		} else {
			mlx5e_activate_qos_sq(priv, node->qid, node->hw_id);
		}
	}

	err = mlx5_qos_destroy_node(htb->mdev, old_hw_id);
	if (err) /* Not fatal. */
		qos_warn(htb->mdev, "Failed to destroy leaf node %u (class %04x), err = %d\n",
			 node->hw_id, classid, err);

	return 0;
}

static int
mlx5e_htb_update_children(struct mlx5e_htb *htb, struct mlx5e_qos_node *node,
			  struct netlink_ext_ack *extack)
{
	struct mlx5e_qos_node *child;
	int err = 0;
	int bkt;

	hash_for_each(htb->qos_tc2node, bkt, child, hnode) {
		u32 old_bw_share = child->bw_share;
		int err_one;

		if (child->parent != node)
			continue;

		mlx5e_htb_convert_rate(htb, child->rate, node, &child->bw_share);
		if (child->bw_share == old_bw_share)
			continue;

		err_one = mlx5_qos_update_node(htb->mdev, child->bw_share,
					       child->max_average_bw, child->hw_id);
		if (!err && err_one) {
			err = err_one;

			NL_SET_ERR_MSG_MOD(extack, "Firmware error when modifying a child node.");
			qos_err(htb->mdev, "Failed to modify a child node (class %04x), err = %d\n",
				node->classid, err);
		}
	}

	return err;
}

int
mlx5e_htb_node_modify(struct mlx5e_htb *htb, u16 classid, u64 rate, u64 ceil,
		      struct netlink_ext_ack *extack)
{
	u32 bw_share, max_average_bw;
	struct mlx5e_qos_node *node;
	bool ceil_changed = false;
	int err;

	qos_dbg(htb->mdev, "TC_HTB_LEAF_MODIFY classid %04x, rate %llu, ceil %llu\n",
		classid, rate, ceil);

	node = mlx5e_htb_node_find(htb, classid);
	if (!node)
		return -ENOENT;

	node->rate = rate;
	mlx5e_htb_convert_rate(htb, rate, node->parent, &bw_share);
	mlx5e_htb_convert_ceil(htb, ceil, &max_average_bw);

	err = mlx5_qos_update_node(htb->mdev, bw_share,
				   max_average_bw, node->hw_id);
	if (err) {
		NL_SET_ERR_MSG_MOD(extack, "Firmware error when modifying a node.");
		qos_err(htb->mdev, "Failed to modify a node (class %04x), err = %d\n",
			classid, err);
		return err;
	}

	if (max_average_bw != node->max_average_bw)
		ceil_changed = true;

	node->bw_share = bw_share;
	node->max_average_bw = max_average_bw;

	if (ceil_changed)
		err = mlx5e_htb_update_children(htb, node, extack);

	return err;
}

struct mlx5e_htb *mlx5e_htb_alloc(void)
{
	return kvzalloc(sizeof(struct mlx5e_htb), GFP_KERNEL);
}

void mlx5e_htb_free(struct mlx5e_htb *htb)
{
	kvfree(htb);
}

int mlx5e_htb_init(struct mlx5e_htb *htb, struct tc_htb_qopt_offload *htb_qopt,
		   struct net_device *netdev, struct mlx5_core_dev *mdev,
		   struct mlx5e_selq *selq, struct mlx5e_priv *priv)
{
	htb->mdev = mdev;
	htb->netdev = netdev;
	htb->selq = selq;
	htb->priv = priv;
	hash_init(htb->qos_tc2node);
	return mlx5e_htb_root_add(htb, htb_qopt->parent_classid, htb_qopt->classid,
				  htb_qopt->extack);
}

void mlx5e_htb_cleanup(struct mlx5e_htb *htb)
{
	mlx5e_htb_root_del(htb);
}