xref: /linux-6.15/drivers/net/netdevsim/netdev.c (revision 5bc8e8db)
1 /*
2  * Copyright (C) 2017 Netronome Systems, Inc.
3  *
4  * This software is licensed under the GNU General License Version 2,
5  * June 1991 as shown in the file COPYING in the top-level directory of this
6  * source tree.
7  *
8  * THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS"
9  * WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
10  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
11  * FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE
12  * OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME
13  * THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
14  */
15 
16 #include <linux/debugfs.h>
17 #include <linux/etherdevice.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/netdevice.h>
21 #include <linux/slab.h>
22 #include <net/netdev_queues.h>
23 #include <net/page_pool/helpers.h>
24 #include <net/netlink.h>
25 #include <net/net_shaper.h>
26 #include <net/pkt_cls.h>
27 #include <net/rtnetlink.h>
28 #include <net/udp_tunnel.h>
29 
30 #include "netdevsim.h"
31 
32 #define NSIM_RING_SIZE		256
33 
34 static int nsim_napi_rx(struct nsim_rq *rq, struct sk_buff *skb)
35 {
36 	if (skb_queue_len(&rq->skb_queue) > NSIM_RING_SIZE) {
37 		dev_kfree_skb_any(skb);
38 		return NET_RX_DROP;
39 	}
40 
41 	skb_queue_tail(&rq->skb_queue, skb);
42 	return NET_RX_SUCCESS;
43 }
44 
45 static int nsim_forward_skb(struct net_device *dev, struct sk_buff *skb,
46 			    struct nsim_rq *rq)
47 {
48 	return __dev_forward_skb(dev, skb) ?: nsim_napi_rx(rq, skb);
49 }
50 
51 static netdev_tx_t nsim_start_xmit(struct sk_buff *skb, struct net_device *dev)
52 {
53 	struct netdevsim *ns = netdev_priv(dev);
54 	struct net_device *peer_dev;
55 	unsigned int len = skb->len;
56 	struct netdevsim *peer_ns;
57 	struct nsim_rq *rq;
58 	int rxq;
59 
60 	rcu_read_lock();
61 	if (!nsim_ipsec_tx(ns, skb))
62 		goto out_drop_free;
63 
64 	peer_ns = rcu_dereference(ns->peer);
65 	if (!peer_ns)
66 		goto out_drop_free;
67 
68 	peer_dev = peer_ns->netdev;
69 	rxq = skb_get_queue_mapping(skb);
70 	if (rxq >= peer_dev->num_rx_queues)
71 		rxq = rxq % peer_dev->num_rx_queues;
72 	rq = peer_ns->rq[rxq];
73 
74 	skb_tx_timestamp(skb);
75 	if (unlikely(nsim_forward_skb(peer_dev, skb, rq) == NET_RX_DROP))
76 		goto out_drop_cnt;
77 
78 	napi_schedule(&rq->napi);
79 
80 	rcu_read_unlock();
81 	u64_stats_update_begin(&ns->syncp);
82 	ns->tx_packets++;
83 	ns->tx_bytes += len;
84 	u64_stats_update_end(&ns->syncp);
85 	return NETDEV_TX_OK;
86 
87 out_drop_free:
88 	dev_kfree_skb(skb);
89 out_drop_cnt:
90 	rcu_read_unlock();
91 	u64_stats_update_begin(&ns->syncp);
92 	ns->tx_dropped++;
93 	u64_stats_update_end(&ns->syncp);
94 	return NETDEV_TX_OK;
95 }
96 
97 static void nsim_set_rx_mode(struct net_device *dev)
98 {
99 }
100 
101 static int nsim_change_mtu(struct net_device *dev, int new_mtu)
102 {
103 	struct netdevsim *ns = netdev_priv(dev);
104 
105 	if (ns->xdp.prog && new_mtu > NSIM_XDP_MAX_MTU)
106 		return -EBUSY;
107 
108 	WRITE_ONCE(dev->mtu, new_mtu);
109 
110 	return 0;
111 }
112 
113 static void
114 nsim_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats)
115 {
116 	struct netdevsim *ns = netdev_priv(dev);
117 	unsigned int start;
118 
119 	do {
120 		start = u64_stats_fetch_begin(&ns->syncp);
121 		stats->tx_bytes = ns->tx_bytes;
122 		stats->tx_packets = ns->tx_packets;
123 		stats->tx_dropped = ns->tx_dropped;
124 	} while (u64_stats_fetch_retry(&ns->syncp, start));
125 }
126 
127 static int
128 nsim_setup_tc_block_cb(enum tc_setup_type type, void *type_data, void *cb_priv)
129 {
130 	return nsim_bpf_setup_tc_block_cb(type, type_data, cb_priv);
131 }
132 
133 static int nsim_set_vf_mac(struct net_device *dev, int vf, u8 *mac)
134 {
135 	struct netdevsim *ns = netdev_priv(dev);
136 	struct nsim_dev *nsim_dev = ns->nsim_dev;
137 
138 	/* Only refuse multicast addresses, zero address can mean unset/any. */
139 	if (vf >= nsim_dev_get_vfs(nsim_dev) || is_multicast_ether_addr(mac))
140 		return -EINVAL;
141 	memcpy(nsim_dev->vfconfigs[vf].vf_mac, mac, ETH_ALEN);
142 
143 	return 0;
144 }
145 
146 static int nsim_set_vf_vlan(struct net_device *dev, int vf,
147 			    u16 vlan, u8 qos, __be16 vlan_proto)
148 {
149 	struct netdevsim *ns = netdev_priv(dev);
150 	struct nsim_dev *nsim_dev = ns->nsim_dev;
151 
152 	if (vf >= nsim_dev_get_vfs(nsim_dev) || vlan > 4095 || qos > 7)
153 		return -EINVAL;
154 
155 	nsim_dev->vfconfigs[vf].vlan = vlan;
156 	nsim_dev->vfconfigs[vf].qos = qos;
157 	nsim_dev->vfconfigs[vf].vlan_proto = vlan_proto;
158 
159 	return 0;
160 }
161 
162 static int nsim_set_vf_rate(struct net_device *dev, int vf, int min, int max)
163 {
164 	struct netdevsim *ns = netdev_priv(dev);
165 	struct nsim_dev *nsim_dev = ns->nsim_dev;
166 
167 	if (nsim_esw_mode_is_switchdev(ns->nsim_dev)) {
168 		pr_err("Not supported in switchdev mode. Please use devlink API.\n");
169 		return -EOPNOTSUPP;
170 	}
171 
172 	if (vf >= nsim_dev_get_vfs(nsim_dev))
173 		return -EINVAL;
174 
175 	nsim_dev->vfconfigs[vf].min_tx_rate = min;
176 	nsim_dev->vfconfigs[vf].max_tx_rate = max;
177 
178 	return 0;
179 }
180 
181 static int nsim_set_vf_spoofchk(struct net_device *dev, int vf, bool val)
182 {
183 	struct netdevsim *ns = netdev_priv(dev);
184 	struct nsim_dev *nsim_dev = ns->nsim_dev;
185 
186 	if (vf >= nsim_dev_get_vfs(nsim_dev))
187 		return -EINVAL;
188 	nsim_dev->vfconfigs[vf].spoofchk_enabled = val;
189 
190 	return 0;
191 }
192 
193 static int nsim_set_vf_rss_query_en(struct net_device *dev, int vf, bool val)
194 {
195 	struct netdevsim *ns = netdev_priv(dev);
196 	struct nsim_dev *nsim_dev = ns->nsim_dev;
197 
198 	if (vf >= nsim_dev_get_vfs(nsim_dev))
199 		return -EINVAL;
200 	nsim_dev->vfconfigs[vf].rss_query_enabled = val;
201 
202 	return 0;
203 }
204 
205 static int nsim_set_vf_trust(struct net_device *dev, int vf, bool val)
206 {
207 	struct netdevsim *ns = netdev_priv(dev);
208 	struct nsim_dev *nsim_dev = ns->nsim_dev;
209 
210 	if (vf >= nsim_dev_get_vfs(nsim_dev))
211 		return -EINVAL;
212 	nsim_dev->vfconfigs[vf].trusted = val;
213 
214 	return 0;
215 }
216 
217 static int
218 nsim_get_vf_config(struct net_device *dev, int vf, struct ifla_vf_info *ivi)
219 {
220 	struct netdevsim *ns = netdev_priv(dev);
221 	struct nsim_dev *nsim_dev = ns->nsim_dev;
222 
223 	if (vf >= nsim_dev_get_vfs(nsim_dev))
224 		return -EINVAL;
225 
226 	ivi->vf = vf;
227 	ivi->linkstate = nsim_dev->vfconfigs[vf].link_state;
228 	ivi->min_tx_rate = nsim_dev->vfconfigs[vf].min_tx_rate;
229 	ivi->max_tx_rate = nsim_dev->vfconfigs[vf].max_tx_rate;
230 	ivi->vlan = nsim_dev->vfconfigs[vf].vlan;
231 	ivi->vlan_proto = nsim_dev->vfconfigs[vf].vlan_proto;
232 	ivi->qos = nsim_dev->vfconfigs[vf].qos;
233 	memcpy(&ivi->mac, nsim_dev->vfconfigs[vf].vf_mac, ETH_ALEN);
234 	ivi->spoofchk = nsim_dev->vfconfigs[vf].spoofchk_enabled;
235 	ivi->trusted = nsim_dev->vfconfigs[vf].trusted;
236 	ivi->rss_query_en = nsim_dev->vfconfigs[vf].rss_query_enabled;
237 
238 	return 0;
239 }
240 
241 static int nsim_set_vf_link_state(struct net_device *dev, int vf, int state)
242 {
243 	struct netdevsim *ns = netdev_priv(dev);
244 	struct nsim_dev *nsim_dev = ns->nsim_dev;
245 
246 	if (vf >= nsim_dev_get_vfs(nsim_dev))
247 		return -EINVAL;
248 
249 	switch (state) {
250 	case IFLA_VF_LINK_STATE_AUTO:
251 	case IFLA_VF_LINK_STATE_ENABLE:
252 	case IFLA_VF_LINK_STATE_DISABLE:
253 		break;
254 	default:
255 		return -EINVAL;
256 	}
257 
258 	nsim_dev->vfconfigs[vf].link_state = state;
259 
260 	return 0;
261 }
262 
263 static void nsim_taprio_stats(struct tc_taprio_qopt_stats *stats)
264 {
265 	stats->window_drops = 0;
266 	stats->tx_overruns = 0;
267 }
268 
269 static int nsim_setup_tc_taprio(struct net_device *dev,
270 				struct tc_taprio_qopt_offload *offload)
271 {
272 	int err = 0;
273 
274 	switch (offload->cmd) {
275 	case TAPRIO_CMD_REPLACE:
276 	case TAPRIO_CMD_DESTROY:
277 		break;
278 	case TAPRIO_CMD_STATS:
279 		nsim_taprio_stats(&offload->stats);
280 		break;
281 	default:
282 		err = -EOPNOTSUPP;
283 	}
284 
285 	return err;
286 }
287 
288 static LIST_HEAD(nsim_block_cb_list);
289 
290 static int
291 nsim_setup_tc(struct net_device *dev, enum tc_setup_type type, void *type_data)
292 {
293 	struct netdevsim *ns = netdev_priv(dev);
294 
295 	switch (type) {
296 	case TC_SETUP_QDISC_TAPRIO:
297 		return nsim_setup_tc_taprio(dev, type_data);
298 	case TC_SETUP_BLOCK:
299 		return flow_block_cb_setup_simple(type_data,
300 						  &nsim_block_cb_list,
301 						  nsim_setup_tc_block_cb,
302 						  ns, ns, true);
303 	default:
304 		return -EOPNOTSUPP;
305 	}
306 }
307 
308 static int
309 nsim_set_features(struct net_device *dev, netdev_features_t features)
310 {
311 	struct netdevsim *ns = netdev_priv(dev);
312 
313 	if ((dev->features & NETIF_F_HW_TC) > (features & NETIF_F_HW_TC))
314 		return nsim_bpf_disable_tc(ns);
315 
316 	return 0;
317 }
318 
319 static int nsim_get_iflink(const struct net_device *dev)
320 {
321 	struct netdevsim *nsim, *peer;
322 	int iflink;
323 
324 	nsim = netdev_priv(dev);
325 
326 	rcu_read_lock();
327 	peer = rcu_dereference(nsim->peer);
328 	iflink = peer ? READ_ONCE(peer->netdev->ifindex) :
329 			READ_ONCE(dev->ifindex);
330 	rcu_read_unlock();
331 
332 	return iflink;
333 }
334 
335 static int nsim_rcv(struct nsim_rq *rq, int budget)
336 {
337 	struct sk_buff *skb;
338 	int i;
339 
340 	for (i = 0; i < budget; i++) {
341 		if (skb_queue_empty(&rq->skb_queue))
342 			break;
343 
344 		skb = skb_dequeue(&rq->skb_queue);
345 		netif_receive_skb(skb);
346 	}
347 
348 	return i;
349 }
350 
351 static int nsim_poll(struct napi_struct *napi, int budget)
352 {
353 	struct nsim_rq *rq = container_of(napi, struct nsim_rq, napi);
354 	int done;
355 
356 	done = nsim_rcv(rq, budget);
357 	napi_complete(napi);
358 
359 	return done;
360 }
361 
362 static int nsim_create_page_pool(struct page_pool **p, struct napi_struct *napi)
363 {
364 	struct page_pool_params params = {
365 		.order = 0,
366 		.pool_size = NSIM_RING_SIZE,
367 		.nid = NUMA_NO_NODE,
368 		.dev = &napi->dev->dev,
369 		.napi = napi,
370 		.dma_dir = DMA_BIDIRECTIONAL,
371 		.netdev = napi->dev,
372 	};
373 	struct page_pool *pool;
374 
375 	pool = page_pool_create(&params);
376 	if (IS_ERR(pool))
377 		return PTR_ERR(pool);
378 
379 	*p = pool;
380 	return 0;
381 }
382 
383 static int nsim_init_napi(struct netdevsim *ns)
384 {
385 	struct net_device *dev = ns->netdev;
386 	struct nsim_rq *rq;
387 	int err, i;
388 
389 	for (i = 0; i < dev->num_rx_queues; i++) {
390 		rq = ns->rq[i];
391 
392 		netif_napi_add_config(dev, &rq->napi, nsim_poll, i);
393 	}
394 
395 	for (i = 0; i < dev->num_rx_queues; i++) {
396 		rq = ns->rq[i];
397 
398 		err = nsim_create_page_pool(&rq->page_pool, &rq->napi);
399 		if (err)
400 			goto err_pp_destroy;
401 	}
402 
403 	return 0;
404 
405 err_pp_destroy:
406 	while (i--) {
407 		page_pool_destroy(ns->rq[i]->page_pool);
408 		ns->rq[i]->page_pool = NULL;
409 	}
410 
411 	for (i = 0; i < dev->num_rx_queues; i++)
412 		__netif_napi_del(&ns->rq[i]->napi);
413 
414 	return err;
415 }
416 
417 static void nsim_enable_napi(struct netdevsim *ns)
418 {
419 	struct net_device *dev = ns->netdev;
420 	int i;
421 
422 	for (i = 0; i < dev->num_rx_queues; i++) {
423 		struct nsim_rq *rq = ns->rq[i];
424 
425 		netif_queue_set_napi(dev, i, NETDEV_QUEUE_TYPE_RX, &rq->napi);
426 		napi_enable(&rq->napi);
427 	}
428 }
429 
430 static int nsim_open(struct net_device *dev)
431 {
432 	struct netdevsim *ns = netdev_priv(dev);
433 	int err;
434 
435 	err = nsim_init_napi(ns);
436 	if (err)
437 		return err;
438 
439 	nsim_enable_napi(ns);
440 
441 	return 0;
442 }
443 
444 static void nsim_del_napi(struct netdevsim *ns)
445 {
446 	struct net_device *dev = ns->netdev;
447 	int i;
448 
449 	for (i = 0; i < dev->num_rx_queues; i++) {
450 		struct nsim_rq *rq = ns->rq[i];
451 
452 		napi_disable(&rq->napi);
453 		__netif_napi_del(&rq->napi);
454 	}
455 	synchronize_net();
456 
457 	for (i = 0; i < dev->num_rx_queues; i++) {
458 		page_pool_destroy(ns->rq[i]->page_pool);
459 		ns->rq[i]->page_pool = NULL;
460 	}
461 }
462 
463 static int nsim_stop(struct net_device *dev)
464 {
465 	struct netdevsim *ns = netdev_priv(dev);
466 	struct netdevsim *peer;
467 
468 	netif_carrier_off(dev);
469 	peer = rtnl_dereference(ns->peer);
470 	if (peer)
471 		netif_carrier_off(peer->netdev);
472 
473 	nsim_del_napi(ns);
474 
475 	return 0;
476 }
477 
478 static int nsim_shaper_set(struct net_shaper_binding *binding,
479 			   const struct net_shaper *shaper,
480 			   struct netlink_ext_ack *extack)
481 {
482 	return 0;
483 }
484 
485 static int nsim_shaper_del(struct net_shaper_binding *binding,
486 			   const struct net_shaper_handle *handle,
487 			   struct netlink_ext_ack *extack)
488 {
489 	return 0;
490 }
491 
492 static int nsim_shaper_group(struct net_shaper_binding *binding,
493 			     int leaves_count,
494 			     const struct net_shaper *leaves,
495 			     const struct net_shaper *root,
496 			     struct netlink_ext_ack *extack)
497 {
498 	return 0;
499 }
500 
501 static void nsim_shaper_cap(struct net_shaper_binding *binding,
502 			    enum net_shaper_scope scope,
503 			    unsigned long *flags)
504 {
505 	*flags = ULONG_MAX;
506 }
507 
508 static const struct net_shaper_ops nsim_shaper_ops = {
509 	.set			= nsim_shaper_set,
510 	.delete			= nsim_shaper_del,
511 	.group			= nsim_shaper_group,
512 	.capabilities		= nsim_shaper_cap,
513 };
514 
515 static const struct net_device_ops nsim_netdev_ops = {
516 	.ndo_start_xmit		= nsim_start_xmit,
517 	.ndo_set_rx_mode	= nsim_set_rx_mode,
518 	.ndo_set_mac_address	= eth_mac_addr,
519 	.ndo_validate_addr	= eth_validate_addr,
520 	.ndo_change_mtu		= nsim_change_mtu,
521 	.ndo_get_stats64	= nsim_get_stats64,
522 	.ndo_set_vf_mac		= nsim_set_vf_mac,
523 	.ndo_set_vf_vlan	= nsim_set_vf_vlan,
524 	.ndo_set_vf_rate	= nsim_set_vf_rate,
525 	.ndo_set_vf_spoofchk	= nsim_set_vf_spoofchk,
526 	.ndo_set_vf_trust	= nsim_set_vf_trust,
527 	.ndo_get_vf_config	= nsim_get_vf_config,
528 	.ndo_set_vf_link_state	= nsim_set_vf_link_state,
529 	.ndo_set_vf_rss_query_en = nsim_set_vf_rss_query_en,
530 	.ndo_setup_tc		= nsim_setup_tc,
531 	.ndo_set_features	= nsim_set_features,
532 	.ndo_get_iflink		= nsim_get_iflink,
533 	.ndo_bpf		= nsim_bpf,
534 	.ndo_open		= nsim_open,
535 	.ndo_stop		= nsim_stop,
536 	.net_shaper_ops		= &nsim_shaper_ops,
537 };
538 
539 static const struct net_device_ops nsim_vf_netdev_ops = {
540 	.ndo_start_xmit		= nsim_start_xmit,
541 	.ndo_set_rx_mode	= nsim_set_rx_mode,
542 	.ndo_set_mac_address	= eth_mac_addr,
543 	.ndo_validate_addr	= eth_validate_addr,
544 	.ndo_change_mtu		= nsim_change_mtu,
545 	.ndo_get_stats64	= nsim_get_stats64,
546 	.ndo_setup_tc		= nsim_setup_tc,
547 	.ndo_set_features	= nsim_set_features,
548 };
549 
550 /* We don't have true per-queue stats, yet, so do some random fakery here.
551  * Only report stuff for queue 0.
552  */
553 static void nsim_get_queue_stats_rx(struct net_device *dev, int idx,
554 				    struct netdev_queue_stats_rx *stats)
555 {
556 	struct rtnl_link_stats64 rtstats = {};
557 
558 	if (!idx)
559 		nsim_get_stats64(dev, &rtstats);
560 
561 	stats->packets = rtstats.rx_packets - !!rtstats.rx_packets;
562 	stats->bytes = rtstats.rx_bytes;
563 }
564 
565 static void nsim_get_queue_stats_tx(struct net_device *dev, int idx,
566 				    struct netdev_queue_stats_tx *stats)
567 {
568 	struct rtnl_link_stats64 rtstats = {};
569 
570 	if (!idx)
571 		nsim_get_stats64(dev, &rtstats);
572 
573 	stats->packets = rtstats.tx_packets - !!rtstats.tx_packets;
574 	stats->bytes = rtstats.tx_bytes;
575 }
576 
577 static void nsim_get_base_stats(struct net_device *dev,
578 				struct netdev_queue_stats_rx *rx,
579 				struct netdev_queue_stats_tx *tx)
580 {
581 	struct rtnl_link_stats64 rtstats = {};
582 
583 	nsim_get_stats64(dev, &rtstats);
584 
585 	rx->packets = !!rtstats.rx_packets;
586 	rx->bytes = 0;
587 	tx->packets = !!rtstats.tx_packets;
588 	tx->bytes = 0;
589 }
590 
591 static const struct netdev_stat_ops nsim_stat_ops = {
592 	.get_queue_stats_tx	= nsim_get_queue_stats_tx,
593 	.get_queue_stats_rx	= nsim_get_queue_stats_rx,
594 	.get_base_stats		= nsim_get_base_stats,
595 };
596 
597 static struct nsim_rq *nsim_queue_alloc(void)
598 {
599 	struct nsim_rq *rq;
600 
601 	rq = kzalloc(sizeof(*rq), GFP_KERNEL_ACCOUNT);
602 	if (!rq)
603 		return NULL;
604 
605 	skb_queue_head_init(&rq->skb_queue);
606 	return rq;
607 }
608 
609 static void nsim_queue_free(struct nsim_rq *rq)
610 {
611 	skb_queue_purge_reason(&rq->skb_queue, SKB_DROP_REASON_QUEUE_PURGE);
612 	kfree(rq);
613 }
614 
615 /* Queue reset mode is controlled by ns->rq_reset_mode.
616  * - normal - new NAPI new pool (old NAPI enabled when new added)
617  * - mode 1 - allocate new pool (NAPI is only disabled / enabled)
618  * - mode 2 - new NAPI new pool (old NAPI removed before new added)
619  * - mode 3 - new NAPI new pool (old NAPI disabled when new added)
620  */
621 struct nsim_queue_mem {
622 	struct nsim_rq *rq;
623 	struct page_pool *pp;
624 };
625 
626 static int
627 nsim_queue_mem_alloc(struct net_device *dev, void *per_queue_mem, int idx)
628 {
629 	struct nsim_queue_mem *qmem = per_queue_mem;
630 	struct netdevsim *ns = netdev_priv(dev);
631 	int err;
632 
633 	if (ns->rq_reset_mode > 3)
634 		return -EINVAL;
635 
636 	if (ns->rq_reset_mode == 1)
637 		return nsim_create_page_pool(&qmem->pp, &ns->rq[idx]->napi);
638 
639 	qmem->rq = nsim_queue_alloc();
640 	if (!qmem->rq)
641 		return -ENOMEM;
642 
643 	err = nsim_create_page_pool(&qmem->rq->page_pool, &qmem->rq->napi);
644 	if (err)
645 		goto err_free;
646 
647 	if (!ns->rq_reset_mode)
648 		netif_napi_add_config(dev, &qmem->rq->napi, nsim_poll, idx);
649 
650 	return 0;
651 
652 err_free:
653 	nsim_queue_free(qmem->rq);
654 	return err;
655 }
656 
657 static void nsim_queue_mem_free(struct net_device *dev, void *per_queue_mem)
658 {
659 	struct nsim_queue_mem *qmem = per_queue_mem;
660 	struct netdevsim *ns = netdev_priv(dev);
661 
662 	page_pool_destroy(qmem->pp);
663 	if (qmem->rq) {
664 		if (!ns->rq_reset_mode)
665 			netif_napi_del(&qmem->rq->napi);
666 		page_pool_destroy(qmem->rq->page_pool);
667 		nsim_queue_free(qmem->rq);
668 	}
669 }
670 
671 static int
672 nsim_queue_start(struct net_device *dev, void *per_queue_mem, int idx)
673 {
674 	struct nsim_queue_mem *qmem = per_queue_mem;
675 	struct netdevsim *ns = netdev_priv(dev);
676 
677 	if (ns->rq_reset_mode == 1) {
678 		ns->rq[idx]->page_pool = qmem->pp;
679 		napi_enable(&ns->rq[idx]->napi);
680 		return 0;
681 	}
682 
683 	/* netif_napi_add()/_del() should normally be called from alloc/free,
684 	 * here we want to test various call orders.
685 	 */
686 	if (ns->rq_reset_mode == 2) {
687 		netif_napi_del(&ns->rq[idx]->napi);
688 		netif_napi_add_config(dev, &qmem->rq->napi, nsim_poll, idx);
689 	} else if (ns->rq_reset_mode == 3) {
690 		netif_napi_add_config(dev, &qmem->rq->napi, nsim_poll, idx);
691 		netif_napi_del(&ns->rq[idx]->napi);
692 	}
693 
694 	ns->rq[idx] = qmem->rq;
695 	napi_enable(&ns->rq[idx]->napi);
696 
697 	return 0;
698 }
699 
700 static int nsim_queue_stop(struct net_device *dev, void *per_queue_mem, int idx)
701 {
702 	struct nsim_queue_mem *qmem = per_queue_mem;
703 	struct netdevsim *ns = netdev_priv(dev);
704 
705 	napi_disable(&ns->rq[idx]->napi);
706 
707 	if (ns->rq_reset_mode == 1) {
708 		qmem->pp = ns->rq[idx]->page_pool;
709 		page_pool_disable_direct_recycling(qmem->pp);
710 	} else {
711 		qmem->rq = ns->rq[idx];
712 	}
713 
714 	return 0;
715 }
716 
717 static const struct netdev_queue_mgmt_ops nsim_queue_mgmt_ops = {
718 	.ndo_queue_mem_size	= sizeof(struct nsim_queue_mem),
719 	.ndo_queue_mem_alloc	= nsim_queue_mem_alloc,
720 	.ndo_queue_mem_free	= nsim_queue_mem_free,
721 	.ndo_queue_start	= nsim_queue_start,
722 	.ndo_queue_stop		= nsim_queue_stop,
723 };
724 
725 static ssize_t
726 nsim_pp_hold_read(struct file *file, char __user *data,
727 		  size_t count, loff_t *ppos)
728 {
729 	struct netdevsim *ns = file->private_data;
730 	char buf[3] = "n\n";
731 
732 	if (ns->page)
733 		buf[0] = 'y';
734 
735 	return simple_read_from_buffer(data, count, ppos, buf, 2);
736 }
737 
738 static ssize_t
739 nsim_pp_hold_write(struct file *file, const char __user *data,
740 		   size_t count, loff_t *ppos)
741 {
742 	struct netdevsim *ns = file->private_data;
743 	ssize_t ret;
744 	bool val;
745 
746 	ret = kstrtobool_from_user(data, count, &val);
747 	if (ret)
748 		return ret;
749 
750 	rtnl_lock();
751 	ret = count;
752 	if (val == !!ns->page)
753 		goto exit;
754 
755 	if (!netif_running(ns->netdev) && val) {
756 		ret = -ENETDOWN;
757 	} else if (val) {
758 		ns->page = page_pool_dev_alloc_pages(ns->rq[0]->page_pool);
759 		if (!ns->page)
760 			ret = -ENOMEM;
761 	} else {
762 		page_pool_put_full_page(ns->page->pp, ns->page, false);
763 		ns->page = NULL;
764 	}
765 
766 exit:
767 	rtnl_unlock();
768 	return ret;
769 }
770 
771 static const struct file_operations nsim_pp_hold_fops = {
772 	.open = simple_open,
773 	.read = nsim_pp_hold_read,
774 	.write = nsim_pp_hold_write,
775 	.llseek = generic_file_llseek,
776 	.owner = THIS_MODULE,
777 };
778 
779 static void nsim_setup(struct net_device *dev)
780 {
781 	ether_setup(dev);
782 	eth_hw_addr_random(dev);
783 
784 	dev->tx_queue_len = 0;
785 	dev->flags &= ~IFF_MULTICAST;
786 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE |
787 			   IFF_NO_QUEUE;
788 	dev->features |= NETIF_F_HIGHDMA |
789 			 NETIF_F_SG |
790 			 NETIF_F_FRAGLIST |
791 			 NETIF_F_HW_CSUM |
792 			 NETIF_F_TSO;
793 	dev->hw_features |= NETIF_F_HW_TC |
794 			    NETIF_F_SG |
795 			    NETIF_F_FRAGLIST |
796 			    NETIF_F_HW_CSUM |
797 			    NETIF_F_TSO;
798 	dev->max_mtu = ETH_MAX_MTU;
799 	dev->xdp_features = NETDEV_XDP_ACT_HW_OFFLOAD;
800 }
801 
802 static int nsim_queue_init(struct netdevsim *ns)
803 {
804 	struct net_device *dev = ns->netdev;
805 	int i;
806 
807 	ns->rq = kcalloc(dev->num_rx_queues, sizeof(*ns->rq),
808 			 GFP_KERNEL_ACCOUNT);
809 	if (!ns->rq)
810 		return -ENOMEM;
811 
812 	for (i = 0; i < dev->num_rx_queues; i++) {
813 		ns->rq[i] = nsim_queue_alloc();
814 		if (!ns->rq[i])
815 			goto err_free_prev;
816 	}
817 
818 	return 0;
819 
820 err_free_prev:
821 	while (i--)
822 		kfree(ns->rq[i]);
823 	kfree(ns->rq);
824 	return -ENOMEM;
825 }
826 
827 static void nsim_queue_uninit(struct netdevsim *ns)
828 {
829 	struct net_device *dev = ns->netdev;
830 	int i;
831 
832 	for (i = 0; i < dev->num_rx_queues; i++)
833 		nsim_queue_free(ns->rq[i]);
834 
835 	kfree(ns->rq);
836 	ns->rq = NULL;
837 }
838 
839 static int nsim_init_netdevsim(struct netdevsim *ns)
840 {
841 	struct mock_phc *phc;
842 	int err;
843 
844 	phc = mock_phc_create(&ns->nsim_bus_dev->dev);
845 	if (IS_ERR(phc))
846 		return PTR_ERR(phc);
847 
848 	ns->phc = phc;
849 	ns->netdev->netdev_ops = &nsim_netdev_ops;
850 	ns->netdev->stat_ops = &nsim_stat_ops;
851 	ns->netdev->queue_mgmt_ops = &nsim_queue_mgmt_ops;
852 
853 	err = nsim_udp_tunnels_info_create(ns->nsim_dev, ns->netdev);
854 	if (err)
855 		goto err_phc_destroy;
856 
857 	rtnl_lock();
858 	err = nsim_queue_init(ns);
859 	if (err)
860 		goto err_utn_destroy;
861 
862 	err = nsim_bpf_init(ns);
863 	if (err)
864 		goto err_rq_destroy;
865 
866 	nsim_macsec_init(ns);
867 	nsim_ipsec_init(ns);
868 
869 	err = register_netdevice(ns->netdev);
870 	if (err)
871 		goto err_ipsec_teardown;
872 	rtnl_unlock();
873 	return 0;
874 
875 err_ipsec_teardown:
876 	nsim_ipsec_teardown(ns);
877 	nsim_macsec_teardown(ns);
878 	nsim_bpf_uninit(ns);
879 err_rq_destroy:
880 	nsim_queue_uninit(ns);
881 err_utn_destroy:
882 	rtnl_unlock();
883 	nsim_udp_tunnels_info_destroy(ns->netdev);
884 err_phc_destroy:
885 	mock_phc_destroy(ns->phc);
886 	return err;
887 }
888 
889 static int nsim_init_netdevsim_vf(struct netdevsim *ns)
890 {
891 	int err;
892 
893 	ns->netdev->netdev_ops = &nsim_vf_netdev_ops;
894 	rtnl_lock();
895 	err = register_netdevice(ns->netdev);
896 	rtnl_unlock();
897 	return err;
898 }
899 
900 static void nsim_exit_netdevsim(struct netdevsim *ns)
901 {
902 	nsim_udp_tunnels_info_destroy(ns->netdev);
903 	mock_phc_destroy(ns->phc);
904 }
905 
906 struct netdevsim *
907 nsim_create(struct nsim_dev *nsim_dev, struct nsim_dev_port *nsim_dev_port)
908 {
909 	struct net_device *dev;
910 	struct netdevsim *ns;
911 	int err;
912 
913 	dev = alloc_netdev_mq(sizeof(*ns), "eth%d", NET_NAME_UNKNOWN, nsim_setup,
914 			      nsim_dev->nsim_bus_dev->num_queues);
915 	if (!dev)
916 		return ERR_PTR(-ENOMEM);
917 
918 	dev_net_set(dev, nsim_dev_net(nsim_dev));
919 	ns = netdev_priv(dev);
920 	ns->netdev = dev;
921 	u64_stats_init(&ns->syncp);
922 	ns->nsim_dev = nsim_dev;
923 	ns->nsim_dev_port = nsim_dev_port;
924 	ns->nsim_bus_dev = nsim_dev->nsim_bus_dev;
925 	SET_NETDEV_DEV(dev, &ns->nsim_bus_dev->dev);
926 	SET_NETDEV_DEVLINK_PORT(dev, &nsim_dev_port->devlink_port);
927 	nsim_ethtool_init(ns);
928 	if (nsim_dev_port_is_pf(nsim_dev_port))
929 		err = nsim_init_netdevsim(ns);
930 	else
931 		err = nsim_init_netdevsim_vf(ns);
932 	if (err)
933 		goto err_free_netdev;
934 
935 	ns->pp_dfs = debugfs_create_file("pp_hold", 0600, nsim_dev_port->ddir,
936 					 ns, &nsim_pp_hold_fops);
937 
938 	return ns;
939 
940 err_free_netdev:
941 	free_netdev(dev);
942 	return ERR_PTR(err);
943 }
944 
945 void nsim_destroy(struct netdevsim *ns)
946 {
947 	struct net_device *dev = ns->netdev;
948 	struct netdevsim *peer;
949 
950 	debugfs_remove(ns->pp_dfs);
951 
952 	rtnl_lock();
953 	peer = rtnl_dereference(ns->peer);
954 	if (peer)
955 		RCU_INIT_POINTER(peer->peer, NULL);
956 	RCU_INIT_POINTER(ns->peer, NULL);
957 	unregister_netdevice(dev);
958 	if (nsim_dev_port_is_pf(ns->nsim_dev_port)) {
959 		nsim_macsec_teardown(ns);
960 		nsim_ipsec_teardown(ns);
961 		nsim_bpf_uninit(ns);
962 		nsim_queue_uninit(ns);
963 	}
964 	rtnl_unlock();
965 	if (nsim_dev_port_is_pf(ns->nsim_dev_port))
966 		nsim_exit_netdevsim(ns);
967 
968 	/* Put this intentionally late to exercise the orphaning path */
969 	if (ns->page) {
970 		page_pool_put_full_page(ns->page->pp, ns->page, false);
971 		ns->page = NULL;
972 	}
973 
974 	free_netdev(dev);
975 }
976 
977 bool netdev_is_nsim(struct net_device *dev)
978 {
979 	return dev->netdev_ops == &nsim_netdev_ops;
980 }
981 
982 static int nsim_validate(struct nlattr *tb[], struct nlattr *data[],
983 			 struct netlink_ext_ack *extack)
984 {
985 	NL_SET_ERR_MSG_MOD(extack,
986 			   "Please use: echo \"[ID] [PORT_COUNT] [NUM_QUEUES]\" > /sys/bus/netdevsim/new_device");
987 	return -EOPNOTSUPP;
988 }
989 
990 static struct rtnl_link_ops nsim_link_ops __read_mostly = {
991 	.kind		= DRV_NAME,
992 	.validate	= nsim_validate,
993 };
994 
995 static int __init nsim_module_init(void)
996 {
997 	int err;
998 
999 	err = nsim_dev_init();
1000 	if (err)
1001 		return err;
1002 
1003 	err = nsim_bus_init();
1004 	if (err)
1005 		goto err_dev_exit;
1006 
1007 	err = rtnl_link_register(&nsim_link_ops);
1008 	if (err)
1009 		goto err_bus_exit;
1010 
1011 	return 0;
1012 
1013 err_bus_exit:
1014 	nsim_bus_exit();
1015 err_dev_exit:
1016 	nsim_dev_exit();
1017 	return err;
1018 }
1019 
1020 static void __exit nsim_module_exit(void)
1021 {
1022 	rtnl_link_unregister(&nsim_link_ops);
1023 	nsim_bus_exit();
1024 	nsim_dev_exit();
1025 }
1026 
1027 module_init(nsim_module_init);
1028 module_exit(nsim_module_exit);
1029 MODULE_LICENSE("GPL");
1030 MODULE_DESCRIPTION("Simulated networking device for testing");
1031 MODULE_ALIAS_RTNL_LINK(DRV_NAME);
1032