1 // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2 /* Copyright (C) 2018 Netronome Systems, Inc. */
3 
4 #include <linux/rtnetlink.h>
5 #include <net/pkt_cls.h>
6 #include <net/pkt_sched.h>
7 #include <net/red.h>
8 
9 #include "../nfpcore/nfp_cpp.h"
10 #include "../nfp_app.h"
11 #include "../nfp_main.h"
12 #include "../nfp_net.h"
13 #include "../nfp_port.h"
14 #include "main.h"
15 
16 static bool nfp_abm_qdisc_is_red(struct nfp_qdisc *qdisc)
17 {
18 	return qdisc->type == NFP_QDISC_RED || qdisc->type == NFP_QDISC_GRED;
19 }
20 
21 static bool nfp_abm_qdisc_child_valid(struct nfp_qdisc *qdisc, unsigned int id)
22 {
23 	return qdisc->children[id] &&
24 	       qdisc->children[id] != NFP_QDISC_UNTRACKED;
25 }
26 
27 static void *nfp_abm_qdisc_tree_deref_slot(void __rcu **slot)
28 {
29 	return rtnl_dereference(*slot);
30 }
31 
32 static void
33 nfp_abm_stats_propagate(struct nfp_alink_stats *parent,
34 			struct nfp_alink_stats *child)
35 {
36 	parent->tx_pkts		+= child->tx_pkts;
37 	parent->tx_bytes	+= child->tx_bytes;
38 	parent->backlog_pkts	+= child->backlog_pkts;
39 	parent->backlog_bytes	+= child->backlog_bytes;
40 	parent->overlimits	+= child->overlimits;
41 	parent->drops		+= child->drops;
42 }
43 
44 static void
45 nfp_abm_stats_update_red(struct nfp_abm_link *alink, struct nfp_qdisc *qdisc,
46 			 unsigned int queue)
47 {
48 	struct nfp_cpp *cpp = alink->abm->app->cpp;
49 	unsigned int i;
50 	int err;
51 
52 	if (!qdisc->offloaded)
53 		return;
54 
55 	for (i = 0; i < qdisc->red.num_bands; i++) {
56 		err = nfp_abm_ctrl_read_q_stats(alink, i, queue,
57 						&qdisc->red.band[i].stats);
58 		if (err)
59 			nfp_err(cpp, "RED stats (%d, %d) read failed with error %d\n",
60 				i, queue, err);
61 
62 		err = nfp_abm_ctrl_read_q_xstats(alink, i, queue,
63 						 &qdisc->red.band[i].xstats);
64 		if (err)
65 			nfp_err(cpp, "RED xstats (%d, %d) read failed with error %d\n",
66 				i, queue, err);
67 	}
68 }
69 
70 static void
71 nfp_abm_stats_update_mq(struct nfp_abm_link *alink, struct nfp_qdisc *qdisc)
72 {
73 	unsigned int i;
74 
75 	if (qdisc->type != NFP_QDISC_MQ)
76 		return;
77 
78 	for (i = 0; i < alink->total_queues; i++)
79 		if (nfp_abm_qdisc_child_valid(qdisc, i))
80 			nfp_abm_stats_update_red(alink, qdisc->children[i], i);
81 }
82 
83 static void __nfp_abm_stats_update(struct nfp_abm_link *alink, u64 time_now)
84 {
85 	alink->last_stats_update = time_now;
86 	if (alink->root_qdisc)
87 		nfp_abm_stats_update_mq(alink, alink->root_qdisc);
88 }
89 
90 static void nfp_abm_stats_update(struct nfp_abm_link *alink)
91 {
92 	u64 now;
93 
94 	/* Limit the frequency of updates - stats of non-leaf qdiscs are a sum
95 	 * of all their leafs, so we would read the same stat multiple times
96 	 * for every dump.
97 	 */
98 	now = ktime_get();
99 	if (now - alink->last_stats_update < NFP_ABM_STATS_REFRESH_IVAL)
100 		return;
101 
102 	__nfp_abm_stats_update(alink, now);
103 }
104 
105 static void
106 nfp_abm_qdisc_unlink_children(struct nfp_qdisc *qdisc,
107 			      unsigned int start, unsigned int end)
108 {
109 	unsigned int i;
110 
111 	for (i = start; i < end; i++)
112 		if (nfp_abm_qdisc_child_valid(qdisc, i)) {
113 			qdisc->children[i]->use_cnt--;
114 			qdisc->children[i] = NULL;
115 		}
116 }
117 
118 static void
119 nfp_abm_qdisc_offload_stop(struct nfp_abm_link *alink, struct nfp_qdisc *qdisc)
120 {
121 	unsigned int i;
122 
123 	/* Don't complain when qdisc is getting unlinked */
124 	if (qdisc->use_cnt)
125 		nfp_warn(alink->abm->app->cpp, "Offload of '%08x' stopped\n",
126 			 qdisc->handle);
127 
128 	if (!nfp_abm_qdisc_is_red(qdisc))
129 		return;
130 
131 	for (i = 0; i < qdisc->red.num_bands; i++) {
132 		qdisc->red.band[i].stats.backlog_pkts = 0;
133 		qdisc->red.band[i].stats.backlog_bytes = 0;
134 	}
135 }
136 
137 static int
138 __nfp_abm_stats_init(struct nfp_abm_link *alink, unsigned int band,
139 		     unsigned int queue, struct nfp_alink_stats *prev_stats,
140 		     struct nfp_alink_xstats *prev_xstats)
141 {
142 	u64 backlog_pkts, backlog_bytes;
143 	int err;
144 
145 	/* Don't touch the backlog, backlog can only be reset after it has
146 	 * been reported back to the tc qdisc stats.
147 	 */
148 	backlog_pkts = prev_stats->backlog_pkts;
149 	backlog_bytes = prev_stats->backlog_bytes;
150 
151 	err = nfp_abm_ctrl_read_q_stats(alink, band, queue, prev_stats);
152 	if (err) {
153 		nfp_err(alink->abm->app->cpp,
154 			"RED stats init (%d, %d) failed with error %d\n",
155 			band, queue, err);
156 		return err;
157 	}
158 
159 	err = nfp_abm_ctrl_read_q_xstats(alink, band, queue, prev_xstats);
160 	if (err) {
161 		nfp_err(alink->abm->app->cpp,
162 			"RED xstats init (%d, %d) failed with error %d\n",
163 			band, queue, err);
164 		return err;
165 	}
166 
167 	prev_stats->backlog_pkts = backlog_pkts;
168 	prev_stats->backlog_bytes = backlog_bytes;
169 	return 0;
170 }
171 
172 static int
173 nfp_abm_stats_init(struct nfp_abm_link *alink, struct nfp_qdisc *qdisc,
174 		   unsigned int queue)
175 {
176 	unsigned int i;
177 	int err;
178 
179 	for (i = 0; i < qdisc->red.num_bands; i++) {
180 		err = __nfp_abm_stats_init(alink, i, queue,
181 					   &qdisc->red.band[i].prev_stats,
182 					   &qdisc->red.band[i].prev_xstats);
183 		if (err)
184 			return err;
185 	}
186 
187 	return 0;
188 }
189 
190 static void
191 nfp_abm_offload_compile_red(struct nfp_abm_link *alink, struct nfp_qdisc *qdisc,
192 			    unsigned int queue)
193 {
194 	bool good_red, good_gred;
195 	unsigned int i;
196 
197 	good_red = qdisc->type == NFP_QDISC_RED &&
198 		   qdisc->params_ok &&
199 		   qdisc->use_cnt == 1 &&
200 		   !alink->has_prio &&
201 		   !qdisc->children[0];
202 	good_gred = qdisc->type == NFP_QDISC_GRED &&
203 		    qdisc->params_ok &&
204 		    qdisc->use_cnt == 1;
205 	qdisc->offload_mark = good_red || good_gred;
206 
207 	/* If we are starting offload init prev_stats */
208 	if (qdisc->offload_mark && !qdisc->offloaded)
209 		if (nfp_abm_stats_init(alink, qdisc, queue))
210 			qdisc->offload_mark = false;
211 
212 	if (!qdisc->offload_mark)
213 		return;
214 
215 	for (i = 0; i < alink->abm->num_bands; i++) {
216 		enum nfp_abm_q_action act;
217 
218 		nfp_abm_ctrl_set_q_lvl(alink, i, queue,
219 				       qdisc->red.band[i].threshold);
220 		act = qdisc->red.band[i].ecn ?
221 			NFP_ABM_ACT_MARK_DROP : NFP_ABM_ACT_DROP;
222 		nfp_abm_ctrl_set_q_act(alink, i, queue, act);
223 	}
224 }
225 
226 static void
227 nfp_abm_offload_compile_mq(struct nfp_abm_link *alink, struct nfp_qdisc *qdisc)
228 {
229 	unsigned int i;
230 
231 	qdisc->offload_mark = qdisc->type == NFP_QDISC_MQ;
232 	if (!qdisc->offload_mark)
233 		return;
234 
235 	for (i = 0; i < alink->total_queues; i++) {
236 		struct nfp_qdisc *child = qdisc->children[i];
237 
238 		if (!nfp_abm_qdisc_child_valid(qdisc, i))
239 			continue;
240 
241 		nfp_abm_offload_compile_red(alink, child, i);
242 	}
243 }
244 
245 void nfp_abm_qdisc_offload_update(struct nfp_abm_link *alink)
246 {
247 	struct nfp_abm *abm = alink->abm;
248 	struct radix_tree_iter iter;
249 	struct nfp_qdisc *qdisc;
250 	void __rcu **slot;
251 	size_t i;
252 
253 	/* Mark all thresholds as unconfigured */
254 	for (i = 0; i < abm->num_bands; i++)
255 		__bitmap_set(abm->threshold_undef,
256 			     i * NFP_NET_MAX_RX_RINGS + alink->queue_base,
257 			     alink->total_queues);
258 
259 	/* Clear offload marks */
260 	radix_tree_for_each_slot(slot, &alink->qdiscs, &iter, 0) {
261 		qdisc = nfp_abm_qdisc_tree_deref_slot(slot);
262 		qdisc->offload_mark = false;
263 	}
264 
265 	if (alink->root_qdisc)
266 		nfp_abm_offload_compile_mq(alink, alink->root_qdisc);
267 
268 	/* Refresh offload status */
269 	radix_tree_for_each_slot(slot, &alink->qdiscs, &iter, 0) {
270 		qdisc = nfp_abm_qdisc_tree_deref_slot(slot);
271 		if (!qdisc->offload_mark && qdisc->offloaded)
272 			nfp_abm_qdisc_offload_stop(alink, qdisc);
273 		qdisc->offloaded = qdisc->offload_mark;
274 	}
275 
276 	/* Reset the unconfigured thresholds */
277 	for (i = 0; i < abm->num_thresholds; i++)
278 		if (test_bit(i, abm->threshold_undef))
279 			__nfp_abm_ctrl_set_q_lvl(abm, i, NFP_ABM_LVL_INFINITY);
280 
281 	__nfp_abm_stats_update(alink, ktime_get());
282 }
283 
284 static void
285 nfp_abm_qdisc_clear_mq(struct net_device *netdev, struct nfp_abm_link *alink,
286 		       struct nfp_qdisc *qdisc)
287 {
288 	struct radix_tree_iter iter;
289 	unsigned int mq_refs = 0;
290 	void __rcu **slot;
291 
292 	if (!qdisc->use_cnt)
293 		return;
294 	/* MQ doesn't notify well on destruction, we need special handling of
295 	 * MQ's children.
296 	 */
297 	if (qdisc->type == NFP_QDISC_MQ &&
298 	    qdisc == alink->root_qdisc &&
299 	    netdev->reg_state == NETREG_UNREGISTERING)
300 		return;
301 
302 	/* Count refs held by MQ instances and clear pointers */
303 	radix_tree_for_each_slot(slot, &alink->qdiscs, &iter, 0) {
304 		struct nfp_qdisc *mq = nfp_abm_qdisc_tree_deref_slot(slot);
305 		unsigned int i;
306 
307 		if (mq->type != NFP_QDISC_MQ || mq->netdev != netdev)
308 			continue;
309 		for (i = 0; i < mq->num_children; i++)
310 			if (mq->children[i] == qdisc) {
311 				mq->children[i] = NULL;
312 				mq_refs++;
313 			}
314 	}
315 
316 	WARN(qdisc->use_cnt != mq_refs, "non-zero qdisc use count: %d (- %d)\n",
317 	     qdisc->use_cnt, mq_refs);
318 }
319 
320 static void
321 nfp_abm_qdisc_free(struct net_device *netdev, struct nfp_abm_link *alink,
322 		   struct nfp_qdisc *qdisc)
323 {
324 	struct nfp_port *port = nfp_port_from_netdev(netdev);
325 
326 	if (!qdisc)
327 		return;
328 	nfp_abm_qdisc_clear_mq(netdev, alink, qdisc);
329 	WARN_ON(radix_tree_delete(&alink->qdiscs,
330 				  TC_H_MAJ(qdisc->handle)) != qdisc);
331 
332 	kfree(qdisc->children);
333 	kfree(qdisc);
334 
335 	port->tc_offload_cnt--;
336 }
337 
338 static struct nfp_qdisc *
339 nfp_abm_qdisc_alloc(struct net_device *netdev, struct nfp_abm_link *alink,
340 		    enum nfp_qdisc_type type, u32 parent_handle, u32 handle,
341 		    unsigned int children)
342 {
343 	struct nfp_port *port = nfp_port_from_netdev(netdev);
344 	struct nfp_qdisc *qdisc;
345 	int err;
346 
347 	qdisc = kzalloc(sizeof(*qdisc), GFP_KERNEL);
348 	if (!qdisc)
349 		return NULL;
350 
351 	if (children) {
352 		qdisc->children = kcalloc(children, sizeof(void *), GFP_KERNEL);
353 		if (!qdisc->children)
354 			goto err_free_qdisc;
355 	}
356 
357 	qdisc->netdev = netdev;
358 	qdisc->type = type;
359 	qdisc->parent_handle = parent_handle;
360 	qdisc->handle = handle;
361 	qdisc->num_children = children;
362 
363 	err = radix_tree_insert(&alink->qdiscs, TC_H_MAJ(qdisc->handle), qdisc);
364 	if (err) {
365 		nfp_err(alink->abm->app->cpp,
366 			"Qdisc insertion into radix tree failed: %d\n", err);
367 		goto err_free_child_tbl;
368 	}
369 
370 	port->tc_offload_cnt++;
371 	return qdisc;
372 
373 err_free_child_tbl:
374 	kfree(qdisc->children);
375 err_free_qdisc:
376 	kfree(qdisc);
377 	return NULL;
378 }
379 
380 static struct nfp_qdisc *
381 nfp_abm_qdisc_find(struct nfp_abm_link *alink, u32 handle)
382 {
383 	return radix_tree_lookup(&alink->qdiscs, TC_H_MAJ(handle));
384 }
385 
386 static int
387 nfp_abm_qdisc_replace(struct net_device *netdev, struct nfp_abm_link *alink,
388 		      enum nfp_qdisc_type type, u32 parent_handle, u32 handle,
389 		      unsigned int children, struct nfp_qdisc **qdisc)
390 {
391 	*qdisc = nfp_abm_qdisc_find(alink, handle);
392 	if (*qdisc) {
393 		if (WARN_ON((*qdisc)->type != type))
394 			return -EINVAL;
395 		return 1;
396 	}
397 
398 	*qdisc = nfp_abm_qdisc_alloc(netdev, alink, type, parent_handle, handle,
399 				     children);
400 	return *qdisc ? 0 : -ENOMEM;
401 }
402 
403 static void
404 nfp_abm_qdisc_destroy(struct net_device *netdev, struct nfp_abm_link *alink,
405 		      u32 handle)
406 {
407 	struct nfp_qdisc *qdisc;
408 
409 	qdisc = nfp_abm_qdisc_find(alink, handle);
410 	if (!qdisc)
411 		return;
412 
413 	/* We don't get TC_SETUP_ROOT_QDISC w/ MQ when netdev is unregistered */
414 	if (alink->root_qdisc == qdisc)
415 		qdisc->use_cnt--;
416 
417 	nfp_abm_qdisc_unlink_children(qdisc, 0, qdisc->num_children);
418 	nfp_abm_qdisc_free(netdev, alink, qdisc);
419 
420 	if (alink->root_qdisc == qdisc) {
421 		alink->root_qdisc = NULL;
422 		/* Only root change matters, other changes are acted upon on
423 		 * the graft notification.
424 		 */
425 		nfp_abm_qdisc_offload_update(alink);
426 	}
427 }
428 
429 static int
430 nfp_abm_qdisc_graft(struct nfp_abm_link *alink, u32 handle, u32 child_handle,
431 		    unsigned int id)
432 {
433 	struct nfp_qdisc *parent, *child;
434 
435 	parent = nfp_abm_qdisc_find(alink, handle);
436 	if (!parent)
437 		return 0;
438 
439 	if (WARN(id >= parent->num_children,
440 		 "graft child out of bound %d >= %d\n",
441 		 id, parent->num_children))
442 		return -EINVAL;
443 
444 	nfp_abm_qdisc_unlink_children(parent, id, id + 1);
445 
446 	child = nfp_abm_qdisc_find(alink, child_handle);
447 	if (child)
448 		child->use_cnt++;
449 	else
450 		child = NFP_QDISC_UNTRACKED;
451 	parent->children[id] = child;
452 
453 	nfp_abm_qdisc_offload_update(alink);
454 
455 	return 0;
456 }
457 
458 static void
459 nfp_abm_stats_calculate(struct nfp_alink_stats *new,
460 			struct nfp_alink_stats *old,
461 			struct gnet_stats_basic_sync *bstats,
462 			struct gnet_stats_queue *qstats)
463 {
464 	_bstats_update(bstats, new->tx_bytes - old->tx_bytes,
465 		       new->tx_pkts - old->tx_pkts);
466 	qstats->qlen += new->backlog_pkts - old->backlog_pkts;
467 	qstats->backlog += new->backlog_bytes - old->backlog_bytes;
468 	qstats->overlimits += new->overlimits - old->overlimits;
469 	qstats->drops += new->drops - old->drops;
470 }
471 
472 static void
473 nfp_abm_stats_red_calculate(struct nfp_alink_xstats *new,
474 			    struct nfp_alink_xstats *old,
475 			    struct red_stats *stats)
476 {
477 	stats->forced_mark += new->ecn_marked - old->ecn_marked;
478 	stats->pdrop += new->pdrop - old->pdrop;
479 }
480 
481 static int
482 nfp_abm_gred_stats(struct nfp_abm_link *alink, u32 handle,
483 		   struct tc_gred_qopt_offload_stats *stats)
484 {
485 	struct nfp_qdisc *qdisc;
486 	unsigned int i;
487 
488 	nfp_abm_stats_update(alink);
489 
490 	qdisc = nfp_abm_qdisc_find(alink, handle);
491 	if (!qdisc)
492 		return -EOPNOTSUPP;
493 	/* If the qdisc offload has stopped we may need to adjust the backlog
494 	 * counters back so carry on even if qdisc is not currently offloaded.
495 	 */
496 
497 	for (i = 0; i < qdisc->red.num_bands; i++) {
498 		if (!stats->xstats[i])
499 			continue;
500 
501 		nfp_abm_stats_calculate(&qdisc->red.band[i].stats,
502 					&qdisc->red.band[i].prev_stats,
503 					&stats->bstats[i], &stats->qstats[i]);
504 		qdisc->red.band[i].prev_stats = qdisc->red.band[i].stats;
505 
506 		nfp_abm_stats_red_calculate(&qdisc->red.band[i].xstats,
507 					    &qdisc->red.band[i].prev_xstats,
508 					    stats->xstats[i]);
509 		qdisc->red.band[i].prev_xstats = qdisc->red.band[i].xstats;
510 	}
511 
512 	return qdisc->offloaded ? 0 : -EOPNOTSUPP;
513 }
514 
515 static bool
516 nfp_abm_gred_check_params(struct nfp_abm_link *alink,
517 			  struct tc_gred_qopt_offload *opt)
518 {
519 	struct nfp_cpp *cpp = alink->abm->app->cpp;
520 	struct nfp_abm *abm = alink->abm;
521 	unsigned int i;
522 
523 	if (opt->set.grio_on || opt->set.wred_on) {
524 		nfp_warn(cpp, "GRED offload failed - GRIO and WRED not supported (p:%08x h:%08x)\n",
525 			 opt->parent, opt->handle);
526 		return false;
527 	}
528 	if (opt->set.dp_def != alink->def_band) {
529 		nfp_warn(cpp, "GRED offload failed - default band must be %d (p:%08x h:%08x)\n",
530 			 alink->def_band, opt->parent, opt->handle);
531 		return false;
532 	}
533 	if (opt->set.dp_cnt != abm->num_bands) {
534 		nfp_warn(cpp, "GRED offload failed - band count must be %d (p:%08x h:%08x)\n",
535 			 abm->num_bands, opt->parent, opt->handle);
536 		return false;
537 	}
538 
539 	for (i = 0; i < abm->num_bands; i++) {
540 		struct tc_gred_vq_qopt_offload_params *band = &opt->set.tab[i];
541 
542 		if (!band->present)
543 			return false;
544 		if (!band->is_ecn && !nfp_abm_has_drop(abm)) {
545 			nfp_warn(cpp, "GRED offload failed - drop is not supported (ECN option required) (p:%08x h:%08x vq:%d)\n",
546 				 opt->parent, opt->handle, i);
547 			return false;
548 		}
549 		if (band->is_ecn && !nfp_abm_has_mark(abm)) {
550 			nfp_warn(cpp, "GRED offload failed - ECN marking not supported (p:%08x h:%08x vq:%d)\n",
551 				 opt->parent, opt->handle, i);
552 			return false;
553 		}
554 		if (band->is_harddrop) {
555 			nfp_warn(cpp, "GRED offload failed - harddrop is not supported (p:%08x h:%08x vq:%d)\n",
556 				 opt->parent, opt->handle, i);
557 			return false;
558 		}
559 		if (band->min != band->max) {
560 			nfp_warn(cpp, "GRED offload failed - threshold mismatch (p:%08x h:%08x vq:%d)\n",
561 				 opt->parent, opt->handle, i);
562 			return false;
563 		}
564 		if (band->min > S32_MAX) {
565 			nfp_warn(cpp, "GRED offload failed - threshold too large %d > %d (p:%08x h:%08x vq:%d)\n",
566 				 band->min, S32_MAX, opt->parent, opt->handle,
567 				 i);
568 			return false;
569 		}
570 	}
571 
572 	return true;
573 }
574 
575 static int
576 nfp_abm_gred_replace(struct net_device *netdev, struct nfp_abm_link *alink,
577 		     struct tc_gred_qopt_offload *opt)
578 {
579 	struct nfp_qdisc *qdisc;
580 	unsigned int i;
581 	int ret;
582 
583 	ret = nfp_abm_qdisc_replace(netdev, alink, NFP_QDISC_GRED, opt->parent,
584 				    opt->handle, 0, &qdisc);
585 	if (ret < 0)
586 		return ret;
587 
588 	qdisc->params_ok = nfp_abm_gred_check_params(alink, opt);
589 	if (qdisc->params_ok) {
590 		qdisc->red.num_bands = opt->set.dp_cnt;
591 		for (i = 0; i < qdisc->red.num_bands; i++) {
592 			qdisc->red.band[i].ecn = opt->set.tab[i].is_ecn;
593 			qdisc->red.band[i].threshold = opt->set.tab[i].min;
594 		}
595 	}
596 
597 	if (qdisc->use_cnt)
598 		nfp_abm_qdisc_offload_update(alink);
599 
600 	return 0;
601 }
602 
603 int nfp_abm_setup_tc_gred(struct net_device *netdev, struct nfp_abm_link *alink,
604 			  struct tc_gred_qopt_offload *opt)
605 {
606 	switch (opt->command) {
607 	case TC_GRED_REPLACE:
608 		return nfp_abm_gred_replace(netdev, alink, opt);
609 	case TC_GRED_DESTROY:
610 		nfp_abm_qdisc_destroy(netdev, alink, opt->handle);
611 		return 0;
612 	case TC_GRED_STATS:
613 		return nfp_abm_gred_stats(alink, opt->handle, &opt->stats);
614 	default:
615 		return -EOPNOTSUPP;
616 	}
617 }
618 
619 static int
620 nfp_abm_red_xstats(struct nfp_abm_link *alink, struct tc_red_qopt_offload *opt)
621 {
622 	struct nfp_qdisc *qdisc;
623 
624 	nfp_abm_stats_update(alink);
625 
626 	qdisc = nfp_abm_qdisc_find(alink, opt->handle);
627 	if (!qdisc || !qdisc->offloaded)
628 		return -EOPNOTSUPP;
629 
630 	nfp_abm_stats_red_calculate(&qdisc->red.band[0].xstats,
631 				    &qdisc->red.band[0].prev_xstats,
632 				    opt->xstats);
633 	qdisc->red.band[0].prev_xstats = qdisc->red.band[0].xstats;
634 	return 0;
635 }
636 
637 static int
638 nfp_abm_red_stats(struct nfp_abm_link *alink, u32 handle,
639 		  struct tc_qopt_offload_stats *stats)
640 {
641 	struct nfp_qdisc *qdisc;
642 
643 	nfp_abm_stats_update(alink);
644 
645 	qdisc = nfp_abm_qdisc_find(alink, handle);
646 	if (!qdisc)
647 		return -EOPNOTSUPP;
648 	/* If the qdisc offload has stopped we may need to adjust the backlog
649 	 * counters back so carry on even if qdisc is not currently offloaded.
650 	 */
651 
652 	nfp_abm_stats_calculate(&qdisc->red.band[0].stats,
653 				&qdisc->red.band[0].prev_stats,
654 				stats->bstats, stats->qstats);
655 	qdisc->red.band[0].prev_stats = qdisc->red.band[0].stats;
656 
657 	return qdisc->offloaded ? 0 : -EOPNOTSUPP;
658 }
659 
660 static bool
661 nfp_abm_red_check_params(struct nfp_abm_link *alink,
662 			 struct tc_red_qopt_offload *opt)
663 {
664 	struct nfp_cpp *cpp = alink->abm->app->cpp;
665 	struct nfp_abm *abm = alink->abm;
666 
667 	if (!opt->set.is_ecn && !nfp_abm_has_drop(abm)) {
668 		nfp_warn(cpp, "RED offload failed - drop is not supported (ECN option required) (p:%08x h:%08x)\n",
669 			 opt->parent, opt->handle);
670 		return false;
671 	}
672 	if (opt->set.is_ecn && !nfp_abm_has_mark(abm)) {
673 		nfp_warn(cpp, "RED offload failed - ECN marking not supported (p:%08x h:%08x)\n",
674 			 opt->parent, opt->handle);
675 		return false;
676 	}
677 	if (opt->set.is_harddrop) {
678 		nfp_warn(cpp, "RED offload failed - harddrop is not supported (p:%08x h:%08x)\n",
679 			 opt->parent, opt->handle);
680 		return false;
681 	}
682 	if (opt->set.min != opt->set.max) {
683 		nfp_warn(cpp, "RED offload failed - unsupported min/max parameters (p:%08x h:%08x)\n",
684 			 opt->parent, opt->handle);
685 		return false;
686 	}
687 	if (opt->set.min > NFP_ABM_LVL_INFINITY) {
688 		nfp_warn(cpp, "RED offload failed - threshold too large %d > %d (p:%08x h:%08x)\n",
689 			 opt->set.min, NFP_ABM_LVL_INFINITY, opt->parent,
690 			 opt->handle);
691 		return false;
692 	}
693 
694 	return true;
695 }
696 
697 static int
698 nfp_abm_red_replace(struct net_device *netdev, struct nfp_abm_link *alink,
699 		    struct tc_red_qopt_offload *opt)
700 {
701 	struct nfp_qdisc *qdisc;
702 	int ret;
703 
704 	ret = nfp_abm_qdisc_replace(netdev, alink, NFP_QDISC_RED, opt->parent,
705 				    opt->handle, 1, &qdisc);
706 	if (ret < 0)
707 		return ret;
708 
709 	/* If limit != 0 child gets reset */
710 	if (opt->set.limit) {
711 		if (nfp_abm_qdisc_child_valid(qdisc, 0))
712 			qdisc->children[0]->use_cnt--;
713 		qdisc->children[0] = NULL;
714 	} else {
715 		/* Qdisc was just allocated without a limit will use noop_qdisc,
716 		 * i.e. a block hole.
717 		 */
718 		if (!ret)
719 			qdisc->children[0] = NFP_QDISC_UNTRACKED;
720 	}
721 
722 	qdisc->params_ok = nfp_abm_red_check_params(alink, opt);
723 	if (qdisc->params_ok) {
724 		qdisc->red.num_bands = 1;
725 		qdisc->red.band[0].ecn = opt->set.is_ecn;
726 		qdisc->red.band[0].threshold = opt->set.min;
727 	}
728 
729 	if (qdisc->use_cnt == 1)
730 		nfp_abm_qdisc_offload_update(alink);
731 
732 	return 0;
733 }
734 
735 int nfp_abm_setup_tc_red(struct net_device *netdev, struct nfp_abm_link *alink,
736 			 struct tc_red_qopt_offload *opt)
737 {
738 	switch (opt->command) {
739 	case TC_RED_REPLACE:
740 		return nfp_abm_red_replace(netdev, alink, opt);
741 	case TC_RED_DESTROY:
742 		nfp_abm_qdisc_destroy(netdev, alink, opt->handle);
743 		return 0;
744 	case TC_RED_STATS:
745 		return nfp_abm_red_stats(alink, opt->handle, &opt->stats);
746 	case TC_RED_XSTATS:
747 		return nfp_abm_red_xstats(alink, opt);
748 	case TC_RED_GRAFT:
749 		return nfp_abm_qdisc_graft(alink, opt->handle,
750 					   opt->child_handle, 0);
751 	default:
752 		return -EOPNOTSUPP;
753 	}
754 }
755 
756 static int
757 nfp_abm_mq_create(struct net_device *netdev, struct nfp_abm_link *alink,
758 		  struct tc_mq_qopt_offload *opt)
759 {
760 	struct nfp_qdisc *qdisc;
761 	int ret;
762 
763 	ret = nfp_abm_qdisc_replace(netdev, alink, NFP_QDISC_MQ,
764 				    TC_H_ROOT, opt->handle, alink->total_queues,
765 				    &qdisc);
766 	if (ret < 0)
767 		return ret;
768 
769 	qdisc->params_ok = true;
770 	qdisc->offloaded = true;
771 	nfp_abm_qdisc_offload_update(alink);
772 	return 0;
773 }
774 
775 static int
776 nfp_abm_mq_stats(struct nfp_abm_link *alink, u32 handle,
777 		 struct tc_qopt_offload_stats *stats)
778 {
779 	struct nfp_qdisc *qdisc, *red;
780 	unsigned int i, j;
781 
782 	qdisc = nfp_abm_qdisc_find(alink, handle);
783 	if (!qdisc)
784 		return -EOPNOTSUPP;
785 
786 	nfp_abm_stats_update(alink);
787 
788 	/* MQ stats are summed over the children in the core, so we need
789 	 * to add up the unreported child values.
790 	 */
791 	memset(&qdisc->mq.stats, 0, sizeof(qdisc->mq.stats));
792 	memset(&qdisc->mq.prev_stats, 0, sizeof(qdisc->mq.prev_stats));
793 
794 	for (i = 0; i < qdisc->num_children; i++) {
795 		if (!nfp_abm_qdisc_child_valid(qdisc, i))
796 			continue;
797 
798 		if (!nfp_abm_qdisc_is_red(qdisc->children[i]))
799 			continue;
800 		red = qdisc->children[i];
801 
802 		for (j = 0; j < red->red.num_bands; j++) {
803 			nfp_abm_stats_propagate(&qdisc->mq.stats,
804 						&red->red.band[j].stats);
805 			nfp_abm_stats_propagate(&qdisc->mq.prev_stats,
806 						&red->red.band[j].prev_stats);
807 		}
808 	}
809 
810 	nfp_abm_stats_calculate(&qdisc->mq.stats, &qdisc->mq.prev_stats,
811 				stats->bstats, stats->qstats);
812 
813 	return qdisc->offloaded ? 0 : -EOPNOTSUPP;
814 }
815 
816 int nfp_abm_setup_tc_mq(struct net_device *netdev, struct nfp_abm_link *alink,
817 			struct tc_mq_qopt_offload *opt)
818 {
819 	switch (opt->command) {
820 	case TC_MQ_CREATE:
821 		return nfp_abm_mq_create(netdev, alink, opt);
822 	case TC_MQ_DESTROY:
823 		nfp_abm_qdisc_destroy(netdev, alink, opt->handle);
824 		return 0;
825 	case TC_MQ_STATS:
826 		return nfp_abm_mq_stats(alink, opt->handle, &opt->stats);
827 	case TC_MQ_GRAFT:
828 		return nfp_abm_qdisc_graft(alink, opt->handle,
829 					   opt->graft_params.child_handle,
830 					   opt->graft_params.queue);
831 	default:
832 		return -EOPNOTSUPP;
833 	}
834 }
835 
836 int nfp_abm_setup_root(struct net_device *netdev, struct nfp_abm_link *alink,
837 		       struct tc_root_qopt_offload *opt)
838 {
839 	if (opt->ingress)
840 		return -EOPNOTSUPP;
841 	if (alink->root_qdisc)
842 		alink->root_qdisc->use_cnt--;
843 	alink->root_qdisc = nfp_abm_qdisc_find(alink, opt->handle);
844 	if (alink->root_qdisc)
845 		alink->root_qdisc->use_cnt++;
846 
847 	nfp_abm_qdisc_offload_update(alink);
848 
849 	return 0;
850 }
851