xref: /linux/drivers/net/netdevsim/netdev.c (revision d1e879ec600f9b3bdd253167533959facfefb17b)
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/ethtool_netlink.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/netdevice.h>
22 #include <linux/slab.h>
23 #include <net/netdev_queues.h>
24 #include <net/netdev_rx_queue.h>
25 #include <net/page_pool/helpers.h>
26 #include <net/netlink.h>
27 #include <net/net_shaper.h>
28 #include <net/pkt_cls.h>
29 #include <net/rtnetlink.h>
30 #include <net/udp_tunnel.h>
31 
32 #include "netdevsim.h"
33 
34 MODULE_IMPORT_NS("NETDEV_INTERNAL");
35 
36 #define NSIM_RING_SIZE		256
37 
38 static int nsim_napi_rx(struct nsim_rq *rq, struct sk_buff *skb)
39 {
40 	if (skb_queue_len(&rq->skb_queue) > NSIM_RING_SIZE) {
41 		dev_kfree_skb_any(skb);
42 		return NET_RX_DROP;
43 	}
44 
45 	skb_queue_tail(&rq->skb_queue, skb);
46 	return NET_RX_SUCCESS;
47 }
48 
49 static int nsim_forward_skb(struct net_device *dev, struct sk_buff *skb,
50 			    struct nsim_rq *rq)
51 {
52 	return __dev_forward_skb(dev, skb) ?: nsim_napi_rx(rq, skb);
53 }
54 
55 static netdev_tx_t nsim_start_xmit(struct sk_buff *skb, struct net_device *dev)
56 {
57 	struct netdevsim *ns = netdev_priv(dev);
58 	struct net_device *peer_dev;
59 	unsigned int len = skb->len;
60 	struct netdevsim *peer_ns;
61 	struct netdev_config *cfg;
62 	struct nsim_rq *rq;
63 	int rxq;
64 
65 	rcu_read_lock();
66 	if (!nsim_ipsec_tx(ns, skb))
67 		goto out_drop_free;
68 
69 	peer_ns = rcu_dereference(ns->peer);
70 	if (!peer_ns)
71 		goto out_drop_free;
72 
73 	peer_dev = peer_ns->netdev;
74 	rxq = skb_get_queue_mapping(skb);
75 	if (rxq >= peer_dev->num_rx_queues)
76 		rxq = rxq % peer_dev->num_rx_queues;
77 	rq = peer_ns->rq[rxq];
78 
79 	cfg = peer_dev->cfg;
80 	if (skb_is_nonlinear(skb) &&
81 	    (cfg->hds_config != ETHTOOL_TCP_DATA_SPLIT_ENABLED ||
82 	     (cfg->hds_config == ETHTOOL_TCP_DATA_SPLIT_ENABLED &&
83 	      cfg->hds_thresh > len)))
84 		skb_linearize(skb);
85 
86 	skb_tx_timestamp(skb);
87 	if (unlikely(nsim_forward_skb(peer_dev, skb, rq) == NET_RX_DROP))
88 		goto out_drop_cnt;
89 
90 	if (!hrtimer_active(&rq->napi_timer))
91 		hrtimer_start(&rq->napi_timer, us_to_ktime(5), HRTIMER_MODE_REL);
92 
93 	rcu_read_unlock();
94 	u64_stats_update_begin(&ns->syncp);
95 	ns->tx_packets++;
96 	ns->tx_bytes += len;
97 	u64_stats_update_end(&ns->syncp);
98 	return NETDEV_TX_OK;
99 
100 out_drop_free:
101 	dev_kfree_skb(skb);
102 out_drop_cnt:
103 	rcu_read_unlock();
104 	u64_stats_update_begin(&ns->syncp);
105 	ns->tx_dropped++;
106 	u64_stats_update_end(&ns->syncp);
107 	return NETDEV_TX_OK;
108 }
109 
110 static void nsim_set_rx_mode(struct net_device *dev)
111 {
112 }
113 
114 static int nsim_change_mtu(struct net_device *dev, int new_mtu)
115 {
116 	struct netdevsim *ns = netdev_priv(dev);
117 
118 	if (ns->xdp.prog && new_mtu > NSIM_XDP_MAX_MTU)
119 		return -EBUSY;
120 
121 	WRITE_ONCE(dev->mtu, new_mtu);
122 
123 	return 0;
124 }
125 
126 static void
127 nsim_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats)
128 {
129 	struct netdevsim *ns = netdev_priv(dev);
130 	unsigned int start;
131 
132 	do {
133 		start = u64_stats_fetch_begin(&ns->syncp);
134 		stats->tx_bytes = ns->tx_bytes;
135 		stats->tx_packets = ns->tx_packets;
136 		stats->tx_dropped = ns->tx_dropped;
137 	} while (u64_stats_fetch_retry(&ns->syncp, start));
138 }
139 
140 static int
141 nsim_setup_tc_block_cb(enum tc_setup_type type, void *type_data, void *cb_priv)
142 {
143 	return nsim_bpf_setup_tc_block_cb(type, type_data, cb_priv);
144 }
145 
146 static int nsim_set_vf_mac(struct net_device *dev, int vf, u8 *mac)
147 {
148 	struct netdevsim *ns = netdev_priv(dev);
149 	struct nsim_dev *nsim_dev = ns->nsim_dev;
150 
151 	/* Only refuse multicast addresses, zero address can mean unset/any. */
152 	if (vf >= nsim_dev_get_vfs(nsim_dev) || is_multicast_ether_addr(mac))
153 		return -EINVAL;
154 	memcpy(nsim_dev->vfconfigs[vf].vf_mac, mac, ETH_ALEN);
155 
156 	return 0;
157 }
158 
159 static int nsim_set_vf_vlan(struct net_device *dev, int vf,
160 			    u16 vlan, u8 qos, __be16 vlan_proto)
161 {
162 	struct netdevsim *ns = netdev_priv(dev);
163 	struct nsim_dev *nsim_dev = ns->nsim_dev;
164 
165 	if (vf >= nsim_dev_get_vfs(nsim_dev) || vlan > 4095 || qos > 7)
166 		return -EINVAL;
167 
168 	nsim_dev->vfconfigs[vf].vlan = vlan;
169 	nsim_dev->vfconfigs[vf].qos = qos;
170 	nsim_dev->vfconfigs[vf].vlan_proto = vlan_proto;
171 
172 	return 0;
173 }
174 
175 static int nsim_set_vf_rate(struct net_device *dev, int vf, int min, int max)
176 {
177 	struct netdevsim *ns = netdev_priv(dev);
178 	struct nsim_dev *nsim_dev = ns->nsim_dev;
179 
180 	if (nsim_esw_mode_is_switchdev(ns->nsim_dev)) {
181 		pr_err("Not supported in switchdev mode. Please use devlink API.\n");
182 		return -EOPNOTSUPP;
183 	}
184 
185 	if (vf >= nsim_dev_get_vfs(nsim_dev))
186 		return -EINVAL;
187 
188 	nsim_dev->vfconfigs[vf].min_tx_rate = min;
189 	nsim_dev->vfconfigs[vf].max_tx_rate = max;
190 
191 	return 0;
192 }
193 
194 static int nsim_set_vf_spoofchk(struct net_device *dev, int vf, bool val)
195 {
196 	struct netdevsim *ns = netdev_priv(dev);
197 	struct nsim_dev *nsim_dev = ns->nsim_dev;
198 
199 	if (vf >= nsim_dev_get_vfs(nsim_dev))
200 		return -EINVAL;
201 	nsim_dev->vfconfigs[vf].spoofchk_enabled = val;
202 
203 	return 0;
204 }
205 
206 static int nsim_set_vf_rss_query_en(struct net_device *dev, int vf, bool val)
207 {
208 	struct netdevsim *ns = netdev_priv(dev);
209 	struct nsim_dev *nsim_dev = ns->nsim_dev;
210 
211 	if (vf >= nsim_dev_get_vfs(nsim_dev))
212 		return -EINVAL;
213 	nsim_dev->vfconfigs[vf].rss_query_enabled = val;
214 
215 	return 0;
216 }
217 
218 static int nsim_set_vf_trust(struct net_device *dev, int vf, bool val)
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 	nsim_dev->vfconfigs[vf].trusted = val;
226 
227 	return 0;
228 }
229 
230 static int
231 nsim_get_vf_config(struct net_device *dev, int vf, struct ifla_vf_info *ivi)
232 {
233 	struct netdevsim *ns = netdev_priv(dev);
234 	struct nsim_dev *nsim_dev = ns->nsim_dev;
235 
236 	if (vf >= nsim_dev_get_vfs(nsim_dev))
237 		return -EINVAL;
238 
239 	ivi->vf = vf;
240 	ivi->linkstate = nsim_dev->vfconfigs[vf].link_state;
241 	ivi->min_tx_rate = nsim_dev->vfconfigs[vf].min_tx_rate;
242 	ivi->max_tx_rate = nsim_dev->vfconfigs[vf].max_tx_rate;
243 	ivi->vlan = nsim_dev->vfconfigs[vf].vlan;
244 	ivi->vlan_proto = nsim_dev->vfconfigs[vf].vlan_proto;
245 	ivi->qos = nsim_dev->vfconfigs[vf].qos;
246 	memcpy(&ivi->mac, nsim_dev->vfconfigs[vf].vf_mac, ETH_ALEN);
247 	ivi->spoofchk = nsim_dev->vfconfigs[vf].spoofchk_enabled;
248 	ivi->trusted = nsim_dev->vfconfigs[vf].trusted;
249 	ivi->rss_query_en = nsim_dev->vfconfigs[vf].rss_query_enabled;
250 
251 	return 0;
252 }
253 
254 static int nsim_set_vf_link_state(struct net_device *dev, int vf, int state)
255 {
256 	struct netdevsim *ns = netdev_priv(dev);
257 	struct nsim_dev *nsim_dev = ns->nsim_dev;
258 
259 	if (vf >= nsim_dev_get_vfs(nsim_dev))
260 		return -EINVAL;
261 
262 	switch (state) {
263 	case IFLA_VF_LINK_STATE_AUTO:
264 	case IFLA_VF_LINK_STATE_ENABLE:
265 	case IFLA_VF_LINK_STATE_DISABLE:
266 		break;
267 	default:
268 		return -EINVAL;
269 	}
270 
271 	nsim_dev->vfconfigs[vf].link_state = state;
272 
273 	return 0;
274 }
275 
276 static void nsim_taprio_stats(struct tc_taprio_qopt_stats *stats)
277 {
278 	stats->window_drops = 0;
279 	stats->tx_overruns = 0;
280 }
281 
282 static int nsim_setup_tc_taprio(struct net_device *dev,
283 				struct tc_taprio_qopt_offload *offload)
284 {
285 	int err = 0;
286 
287 	switch (offload->cmd) {
288 	case TAPRIO_CMD_REPLACE:
289 	case TAPRIO_CMD_DESTROY:
290 		break;
291 	case TAPRIO_CMD_STATS:
292 		nsim_taprio_stats(&offload->stats);
293 		break;
294 	default:
295 		err = -EOPNOTSUPP;
296 	}
297 
298 	return err;
299 }
300 
301 static LIST_HEAD(nsim_block_cb_list);
302 
303 static int
304 nsim_setup_tc(struct net_device *dev, enum tc_setup_type type, void *type_data)
305 {
306 	struct netdevsim *ns = netdev_priv(dev);
307 
308 	switch (type) {
309 	case TC_SETUP_QDISC_TAPRIO:
310 		return nsim_setup_tc_taprio(dev, type_data);
311 	case TC_SETUP_BLOCK:
312 		return flow_block_cb_setup_simple(type_data,
313 						  &nsim_block_cb_list,
314 						  nsim_setup_tc_block_cb,
315 						  ns, ns, true);
316 	default:
317 		return -EOPNOTSUPP;
318 	}
319 }
320 
321 static int
322 nsim_set_features(struct net_device *dev, netdev_features_t features)
323 {
324 	struct netdevsim *ns = netdev_priv(dev);
325 
326 	if ((dev->features & NETIF_F_HW_TC) > (features & NETIF_F_HW_TC))
327 		return nsim_bpf_disable_tc(ns);
328 
329 	return 0;
330 }
331 
332 static int nsim_get_iflink(const struct net_device *dev)
333 {
334 	struct netdevsim *nsim, *peer;
335 	int iflink;
336 
337 	nsim = netdev_priv(dev);
338 
339 	rcu_read_lock();
340 	peer = rcu_dereference(nsim->peer);
341 	iflink = peer ? READ_ONCE(peer->netdev->ifindex) :
342 			READ_ONCE(dev->ifindex);
343 	rcu_read_unlock();
344 
345 	return iflink;
346 }
347 
348 static int nsim_rcv(struct nsim_rq *rq, int budget)
349 {
350 	struct sk_buff *skb;
351 	int i;
352 
353 	for (i = 0; i < budget; i++) {
354 		if (skb_queue_empty(&rq->skb_queue))
355 			break;
356 
357 		skb = skb_dequeue(&rq->skb_queue);
358 		netif_receive_skb(skb);
359 	}
360 
361 	return i;
362 }
363 
364 static int nsim_poll(struct napi_struct *napi, int budget)
365 {
366 	struct nsim_rq *rq = container_of(napi, struct nsim_rq, napi);
367 	int done;
368 
369 	done = nsim_rcv(rq, budget);
370 	napi_complete(napi);
371 
372 	return done;
373 }
374 
375 static int nsim_create_page_pool(struct page_pool **p, struct napi_struct *napi)
376 {
377 	struct page_pool_params params = {
378 		.order = 0,
379 		.pool_size = NSIM_RING_SIZE,
380 		.nid = NUMA_NO_NODE,
381 		.dev = &napi->dev->dev,
382 		.napi = napi,
383 		.dma_dir = DMA_BIDIRECTIONAL,
384 		.netdev = napi->dev,
385 	};
386 	struct page_pool *pool;
387 
388 	pool = page_pool_create(&params);
389 	if (IS_ERR(pool))
390 		return PTR_ERR(pool);
391 
392 	*p = pool;
393 	return 0;
394 }
395 
396 static int nsim_init_napi(struct netdevsim *ns)
397 {
398 	struct net_device *dev = ns->netdev;
399 	struct nsim_rq *rq;
400 	int err, i;
401 
402 	for (i = 0; i < dev->num_rx_queues; i++) {
403 		rq = ns->rq[i];
404 
405 		netif_napi_add_config(dev, &rq->napi, nsim_poll, i);
406 	}
407 
408 	for (i = 0; i < dev->num_rx_queues; i++) {
409 		rq = ns->rq[i];
410 
411 		err = nsim_create_page_pool(&rq->page_pool, &rq->napi);
412 		if (err)
413 			goto err_pp_destroy;
414 	}
415 
416 	return 0;
417 
418 err_pp_destroy:
419 	while (i--) {
420 		page_pool_destroy(ns->rq[i]->page_pool);
421 		ns->rq[i]->page_pool = NULL;
422 	}
423 
424 	for (i = 0; i < dev->num_rx_queues; i++)
425 		__netif_napi_del(&ns->rq[i]->napi);
426 
427 	return err;
428 }
429 
430 static enum hrtimer_restart nsim_napi_schedule(struct hrtimer *timer)
431 {
432 	struct nsim_rq *rq;
433 
434 	rq = container_of(timer, struct nsim_rq, napi_timer);
435 	napi_schedule(&rq->napi);
436 
437 	return HRTIMER_NORESTART;
438 }
439 
440 static void nsim_rq_timer_init(struct nsim_rq *rq)
441 {
442 	hrtimer_init(&rq->napi_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
443 	rq->napi_timer.function = nsim_napi_schedule;
444 }
445 
446 static void nsim_enable_napi(struct netdevsim *ns)
447 {
448 	struct net_device *dev = ns->netdev;
449 	int i;
450 
451 	for (i = 0; i < dev->num_rx_queues; i++) {
452 		struct nsim_rq *rq = ns->rq[i];
453 
454 		netif_queue_set_napi(dev, i, NETDEV_QUEUE_TYPE_RX, &rq->napi);
455 		napi_enable(&rq->napi);
456 	}
457 }
458 
459 static int nsim_open(struct net_device *dev)
460 {
461 	struct netdevsim *ns = netdev_priv(dev);
462 	int err;
463 
464 	err = nsim_init_napi(ns);
465 	if (err)
466 		return err;
467 
468 	nsim_enable_napi(ns);
469 
470 	return 0;
471 }
472 
473 static void nsim_del_napi(struct netdevsim *ns)
474 {
475 	struct net_device *dev = ns->netdev;
476 	int i;
477 
478 	for (i = 0; i < dev->num_rx_queues; i++) {
479 		struct nsim_rq *rq = ns->rq[i];
480 
481 		napi_disable(&rq->napi);
482 		__netif_napi_del(&rq->napi);
483 	}
484 	synchronize_net();
485 
486 	for (i = 0; i < dev->num_rx_queues; i++) {
487 		page_pool_destroy(ns->rq[i]->page_pool);
488 		ns->rq[i]->page_pool = NULL;
489 	}
490 }
491 
492 static int nsim_stop(struct net_device *dev)
493 {
494 	struct netdevsim *ns = netdev_priv(dev);
495 	struct netdevsim *peer;
496 
497 	netif_carrier_off(dev);
498 	peer = rtnl_dereference(ns->peer);
499 	if (peer)
500 		netif_carrier_off(peer->netdev);
501 
502 	nsim_del_napi(ns);
503 
504 	return 0;
505 }
506 
507 static int nsim_shaper_set(struct net_shaper_binding *binding,
508 			   const struct net_shaper *shaper,
509 			   struct netlink_ext_ack *extack)
510 {
511 	return 0;
512 }
513 
514 static int nsim_shaper_del(struct net_shaper_binding *binding,
515 			   const struct net_shaper_handle *handle,
516 			   struct netlink_ext_ack *extack)
517 {
518 	return 0;
519 }
520 
521 static int nsim_shaper_group(struct net_shaper_binding *binding,
522 			     int leaves_count,
523 			     const struct net_shaper *leaves,
524 			     const struct net_shaper *root,
525 			     struct netlink_ext_ack *extack)
526 {
527 	return 0;
528 }
529 
530 static void nsim_shaper_cap(struct net_shaper_binding *binding,
531 			    enum net_shaper_scope scope,
532 			    unsigned long *flags)
533 {
534 	*flags = ULONG_MAX;
535 }
536 
537 static const struct net_shaper_ops nsim_shaper_ops = {
538 	.set			= nsim_shaper_set,
539 	.delete			= nsim_shaper_del,
540 	.group			= nsim_shaper_group,
541 	.capabilities		= nsim_shaper_cap,
542 };
543 
544 static const struct net_device_ops nsim_netdev_ops = {
545 	.ndo_start_xmit		= nsim_start_xmit,
546 	.ndo_set_rx_mode	= nsim_set_rx_mode,
547 	.ndo_set_mac_address	= eth_mac_addr,
548 	.ndo_validate_addr	= eth_validate_addr,
549 	.ndo_change_mtu		= nsim_change_mtu,
550 	.ndo_get_stats64	= nsim_get_stats64,
551 	.ndo_set_vf_mac		= nsim_set_vf_mac,
552 	.ndo_set_vf_vlan	= nsim_set_vf_vlan,
553 	.ndo_set_vf_rate	= nsim_set_vf_rate,
554 	.ndo_set_vf_spoofchk	= nsim_set_vf_spoofchk,
555 	.ndo_set_vf_trust	= nsim_set_vf_trust,
556 	.ndo_get_vf_config	= nsim_get_vf_config,
557 	.ndo_set_vf_link_state	= nsim_set_vf_link_state,
558 	.ndo_set_vf_rss_query_en = nsim_set_vf_rss_query_en,
559 	.ndo_setup_tc		= nsim_setup_tc,
560 	.ndo_set_features	= nsim_set_features,
561 	.ndo_get_iflink		= nsim_get_iflink,
562 	.ndo_bpf		= nsim_bpf,
563 	.ndo_open		= nsim_open,
564 	.ndo_stop		= nsim_stop,
565 	.net_shaper_ops		= &nsim_shaper_ops,
566 };
567 
568 static const struct net_device_ops nsim_vf_netdev_ops = {
569 	.ndo_start_xmit		= nsim_start_xmit,
570 	.ndo_set_rx_mode	= nsim_set_rx_mode,
571 	.ndo_set_mac_address	= eth_mac_addr,
572 	.ndo_validate_addr	= eth_validate_addr,
573 	.ndo_change_mtu		= nsim_change_mtu,
574 	.ndo_get_stats64	= nsim_get_stats64,
575 	.ndo_setup_tc		= nsim_setup_tc,
576 	.ndo_set_features	= nsim_set_features,
577 };
578 
579 /* We don't have true per-queue stats, yet, so do some random fakery here.
580  * Only report stuff for queue 0.
581  */
582 static void nsim_get_queue_stats_rx(struct net_device *dev, int idx,
583 				    struct netdev_queue_stats_rx *stats)
584 {
585 	struct rtnl_link_stats64 rtstats = {};
586 
587 	if (!idx)
588 		nsim_get_stats64(dev, &rtstats);
589 
590 	stats->packets = rtstats.rx_packets - !!rtstats.rx_packets;
591 	stats->bytes = rtstats.rx_bytes;
592 }
593 
594 static void nsim_get_queue_stats_tx(struct net_device *dev, int idx,
595 				    struct netdev_queue_stats_tx *stats)
596 {
597 	struct rtnl_link_stats64 rtstats = {};
598 
599 	if (!idx)
600 		nsim_get_stats64(dev, &rtstats);
601 
602 	stats->packets = rtstats.tx_packets - !!rtstats.tx_packets;
603 	stats->bytes = rtstats.tx_bytes;
604 }
605 
606 static void nsim_get_base_stats(struct net_device *dev,
607 				struct netdev_queue_stats_rx *rx,
608 				struct netdev_queue_stats_tx *tx)
609 {
610 	struct rtnl_link_stats64 rtstats = {};
611 
612 	nsim_get_stats64(dev, &rtstats);
613 
614 	rx->packets = !!rtstats.rx_packets;
615 	rx->bytes = 0;
616 	tx->packets = !!rtstats.tx_packets;
617 	tx->bytes = 0;
618 }
619 
620 static const struct netdev_stat_ops nsim_stat_ops = {
621 	.get_queue_stats_tx	= nsim_get_queue_stats_tx,
622 	.get_queue_stats_rx	= nsim_get_queue_stats_rx,
623 	.get_base_stats		= nsim_get_base_stats,
624 };
625 
626 static struct nsim_rq *nsim_queue_alloc(void)
627 {
628 	struct nsim_rq *rq;
629 
630 	rq = kzalloc(sizeof(*rq), GFP_KERNEL_ACCOUNT);
631 	if (!rq)
632 		return NULL;
633 
634 	skb_queue_head_init(&rq->skb_queue);
635 	nsim_rq_timer_init(rq);
636 	return rq;
637 }
638 
639 static void nsim_queue_free(struct nsim_rq *rq)
640 {
641 	hrtimer_cancel(&rq->napi_timer);
642 	skb_queue_purge_reason(&rq->skb_queue, SKB_DROP_REASON_QUEUE_PURGE);
643 	kfree(rq);
644 }
645 
646 /* Queue reset mode is controlled by ns->rq_reset_mode.
647  * - normal - new NAPI new pool (old NAPI enabled when new added)
648  * - mode 1 - allocate new pool (NAPI is only disabled / enabled)
649  * - mode 2 - new NAPI new pool (old NAPI removed before new added)
650  * - mode 3 - new NAPI new pool (old NAPI disabled when new added)
651  */
652 struct nsim_queue_mem {
653 	struct nsim_rq *rq;
654 	struct page_pool *pp;
655 };
656 
657 static int
658 nsim_queue_mem_alloc(struct net_device *dev, void *per_queue_mem, int idx)
659 {
660 	struct nsim_queue_mem *qmem = per_queue_mem;
661 	struct netdevsim *ns = netdev_priv(dev);
662 	int err;
663 
664 	if (ns->rq_reset_mode > 3)
665 		return -EINVAL;
666 
667 	if (ns->rq_reset_mode == 1) {
668 		if (!netif_running(ns->netdev))
669 			return -ENETDOWN;
670 		return nsim_create_page_pool(&qmem->pp, &ns->rq[idx]->napi);
671 	}
672 
673 	qmem->rq = nsim_queue_alloc();
674 	if (!qmem->rq)
675 		return -ENOMEM;
676 
677 	err = nsim_create_page_pool(&qmem->rq->page_pool, &qmem->rq->napi);
678 	if (err)
679 		goto err_free;
680 
681 	if (!ns->rq_reset_mode)
682 		netif_napi_add_config(dev, &qmem->rq->napi, nsim_poll, idx);
683 
684 	return 0;
685 
686 err_free:
687 	nsim_queue_free(qmem->rq);
688 	return err;
689 }
690 
691 static void nsim_queue_mem_free(struct net_device *dev, void *per_queue_mem)
692 {
693 	struct nsim_queue_mem *qmem = per_queue_mem;
694 	struct netdevsim *ns = netdev_priv(dev);
695 
696 	page_pool_destroy(qmem->pp);
697 	if (qmem->rq) {
698 		if (!ns->rq_reset_mode)
699 			netif_napi_del(&qmem->rq->napi);
700 		page_pool_destroy(qmem->rq->page_pool);
701 		nsim_queue_free(qmem->rq);
702 	}
703 }
704 
705 static int
706 nsim_queue_start(struct net_device *dev, void *per_queue_mem, int idx)
707 {
708 	struct nsim_queue_mem *qmem = per_queue_mem;
709 	struct netdevsim *ns = netdev_priv(dev);
710 
711 	if (ns->rq_reset_mode == 1) {
712 		ns->rq[idx]->page_pool = qmem->pp;
713 		napi_enable(&ns->rq[idx]->napi);
714 		return 0;
715 	}
716 
717 	/* netif_napi_add()/_del() should normally be called from alloc/free,
718 	 * here we want to test various call orders.
719 	 */
720 	if (ns->rq_reset_mode == 2) {
721 		netif_napi_del(&ns->rq[idx]->napi);
722 		netif_napi_add_config(dev, &qmem->rq->napi, nsim_poll, idx);
723 	} else if (ns->rq_reset_mode == 3) {
724 		netif_napi_add_config(dev, &qmem->rq->napi, nsim_poll, idx);
725 		netif_napi_del(&ns->rq[idx]->napi);
726 	}
727 
728 	ns->rq[idx] = qmem->rq;
729 	napi_enable(&ns->rq[idx]->napi);
730 
731 	return 0;
732 }
733 
734 static int nsim_queue_stop(struct net_device *dev, void *per_queue_mem, int idx)
735 {
736 	struct nsim_queue_mem *qmem = per_queue_mem;
737 	struct netdevsim *ns = netdev_priv(dev);
738 
739 	napi_disable(&ns->rq[idx]->napi);
740 
741 	if (ns->rq_reset_mode == 1) {
742 		qmem->pp = ns->rq[idx]->page_pool;
743 		page_pool_disable_direct_recycling(qmem->pp);
744 	} else {
745 		qmem->rq = ns->rq[idx];
746 	}
747 
748 	return 0;
749 }
750 
751 static const struct netdev_queue_mgmt_ops nsim_queue_mgmt_ops = {
752 	.ndo_queue_mem_size	= sizeof(struct nsim_queue_mem),
753 	.ndo_queue_mem_alloc	= nsim_queue_mem_alloc,
754 	.ndo_queue_mem_free	= nsim_queue_mem_free,
755 	.ndo_queue_start	= nsim_queue_start,
756 	.ndo_queue_stop		= nsim_queue_stop,
757 };
758 
759 static ssize_t
760 nsim_qreset_write(struct file *file, const char __user *data,
761 		  size_t count, loff_t *ppos)
762 {
763 	struct netdevsim *ns = file->private_data;
764 	unsigned int queue, mode;
765 	char buf[32];
766 	ssize_t ret;
767 
768 	if (count >= sizeof(buf))
769 		return -EINVAL;
770 	if (copy_from_user(buf, data, count))
771 		return -EFAULT;
772 	buf[count] = '\0';
773 
774 	ret = sscanf(buf, "%u %u", &queue, &mode);
775 	if (ret != 2)
776 		return -EINVAL;
777 
778 	rtnl_lock();
779 	if (queue >= ns->netdev->real_num_rx_queues) {
780 		ret = -EINVAL;
781 		goto exit_unlock;
782 	}
783 
784 	ns->rq_reset_mode = mode;
785 	ret = netdev_rx_queue_restart(ns->netdev, queue);
786 	ns->rq_reset_mode = 0;
787 	if (ret)
788 		goto exit_unlock;
789 
790 	ret = count;
791 exit_unlock:
792 	rtnl_unlock();
793 	return ret;
794 }
795 
796 static const struct file_operations nsim_qreset_fops = {
797 	.open = simple_open,
798 	.write = nsim_qreset_write,
799 	.owner = THIS_MODULE,
800 };
801 
802 static ssize_t
803 nsim_pp_hold_read(struct file *file, char __user *data,
804 		  size_t count, loff_t *ppos)
805 {
806 	struct netdevsim *ns = file->private_data;
807 	char buf[3] = "n\n";
808 
809 	if (ns->page)
810 		buf[0] = 'y';
811 
812 	return simple_read_from_buffer(data, count, ppos, buf, 2);
813 }
814 
815 static ssize_t
816 nsim_pp_hold_write(struct file *file, const char __user *data,
817 		   size_t count, loff_t *ppos)
818 {
819 	struct netdevsim *ns = file->private_data;
820 	ssize_t ret;
821 	bool val;
822 
823 	ret = kstrtobool_from_user(data, count, &val);
824 	if (ret)
825 		return ret;
826 
827 	rtnl_lock();
828 	ret = count;
829 	if (val == !!ns->page)
830 		goto exit;
831 
832 	if (!netif_running(ns->netdev) && val) {
833 		ret = -ENETDOWN;
834 	} else if (val) {
835 		ns->page = page_pool_dev_alloc_pages(ns->rq[0]->page_pool);
836 		if (!ns->page)
837 			ret = -ENOMEM;
838 	} else {
839 		page_pool_put_full_page(ns->page->pp, ns->page, false);
840 		ns->page = NULL;
841 	}
842 
843 exit:
844 	rtnl_unlock();
845 	return ret;
846 }
847 
848 static const struct file_operations nsim_pp_hold_fops = {
849 	.open = simple_open,
850 	.read = nsim_pp_hold_read,
851 	.write = nsim_pp_hold_write,
852 	.llseek = generic_file_llseek,
853 	.owner = THIS_MODULE,
854 };
855 
856 static void nsim_setup(struct net_device *dev)
857 {
858 	ether_setup(dev);
859 	eth_hw_addr_random(dev);
860 
861 	dev->tx_queue_len = 0;
862 	dev->flags &= ~IFF_MULTICAST;
863 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE |
864 			   IFF_NO_QUEUE;
865 	dev->features |= NETIF_F_HIGHDMA |
866 			 NETIF_F_SG |
867 			 NETIF_F_FRAGLIST |
868 			 NETIF_F_HW_CSUM |
869 			 NETIF_F_TSO;
870 	dev->hw_features |= NETIF_F_HW_TC |
871 			    NETIF_F_SG |
872 			    NETIF_F_FRAGLIST |
873 			    NETIF_F_HW_CSUM |
874 			    NETIF_F_TSO;
875 	dev->max_mtu = ETH_MAX_MTU;
876 	dev->xdp_features = NETDEV_XDP_ACT_HW_OFFLOAD;
877 }
878 
879 static int nsim_queue_init(struct netdevsim *ns)
880 {
881 	struct net_device *dev = ns->netdev;
882 	int i;
883 
884 	ns->rq = kcalloc(dev->num_rx_queues, sizeof(*ns->rq),
885 			 GFP_KERNEL_ACCOUNT);
886 	if (!ns->rq)
887 		return -ENOMEM;
888 
889 	for (i = 0; i < dev->num_rx_queues; i++) {
890 		ns->rq[i] = nsim_queue_alloc();
891 		if (!ns->rq[i])
892 			goto err_free_prev;
893 	}
894 
895 	return 0;
896 
897 err_free_prev:
898 	while (i--)
899 		kfree(ns->rq[i]);
900 	kfree(ns->rq);
901 	return -ENOMEM;
902 }
903 
904 static void nsim_queue_uninit(struct netdevsim *ns)
905 {
906 	struct net_device *dev = ns->netdev;
907 	int i;
908 
909 	for (i = 0; i < dev->num_rx_queues; i++)
910 		nsim_queue_free(ns->rq[i]);
911 
912 	kfree(ns->rq);
913 	ns->rq = NULL;
914 }
915 
916 static int nsim_init_netdevsim(struct netdevsim *ns)
917 {
918 	struct mock_phc *phc;
919 	int err;
920 
921 	phc = mock_phc_create(&ns->nsim_bus_dev->dev);
922 	if (IS_ERR(phc))
923 		return PTR_ERR(phc);
924 
925 	ns->phc = phc;
926 	ns->netdev->netdev_ops = &nsim_netdev_ops;
927 	ns->netdev->stat_ops = &nsim_stat_ops;
928 	ns->netdev->queue_mgmt_ops = &nsim_queue_mgmt_ops;
929 
930 	err = nsim_udp_tunnels_info_create(ns->nsim_dev, ns->netdev);
931 	if (err)
932 		goto err_phc_destroy;
933 
934 	rtnl_lock();
935 	err = nsim_queue_init(ns);
936 	if (err)
937 		goto err_utn_destroy;
938 
939 	err = nsim_bpf_init(ns);
940 	if (err)
941 		goto err_rq_destroy;
942 
943 	nsim_macsec_init(ns);
944 	nsim_ipsec_init(ns);
945 
946 	err = register_netdevice(ns->netdev);
947 	if (err)
948 		goto err_ipsec_teardown;
949 	rtnl_unlock();
950 	return 0;
951 
952 err_ipsec_teardown:
953 	nsim_ipsec_teardown(ns);
954 	nsim_macsec_teardown(ns);
955 	nsim_bpf_uninit(ns);
956 err_rq_destroy:
957 	nsim_queue_uninit(ns);
958 err_utn_destroy:
959 	rtnl_unlock();
960 	nsim_udp_tunnels_info_destroy(ns->netdev);
961 err_phc_destroy:
962 	mock_phc_destroy(ns->phc);
963 	return err;
964 }
965 
966 static int nsim_init_netdevsim_vf(struct netdevsim *ns)
967 {
968 	int err;
969 
970 	ns->netdev->netdev_ops = &nsim_vf_netdev_ops;
971 	rtnl_lock();
972 	err = register_netdevice(ns->netdev);
973 	rtnl_unlock();
974 	return err;
975 }
976 
977 static void nsim_exit_netdevsim(struct netdevsim *ns)
978 {
979 	nsim_udp_tunnels_info_destroy(ns->netdev);
980 	mock_phc_destroy(ns->phc);
981 }
982 
983 struct netdevsim *
984 nsim_create(struct nsim_dev *nsim_dev, struct nsim_dev_port *nsim_dev_port)
985 {
986 	struct net_device *dev;
987 	struct netdevsim *ns;
988 	int err;
989 
990 	dev = alloc_netdev_mq(sizeof(*ns), "eth%d", NET_NAME_UNKNOWN, nsim_setup,
991 			      nsim_dev->nsim_bus_dev->num_queues);
992 	if (!dev)
993 		return ERR_PTR(-ENOMEM);
994 
995 	dev_net_set(dev, nsim_dev_net(nsim_dev));
996 	ns = netdev_priv(dev);
997 	ns->netdev = dev;
998 	u64_stats_init(&ns->syncp);
999 	ns->nsim_dev = nsim_dev;
1000 	ns->nsim_dev_port = nsim_dev_port;
1001 	ns->nsim_bus_dev = nsim_dev->nsim_bus_dev;
1002 	SET_NETDEV_DEV(dev, &ns->nsim_bus_dev->dev);
1003 	SET_NETDEV_DEVLINK_PORT(dev, &nsim_dev_port->devlink_port);
1004 	nsim_ethtool_init(ns);
1005 	if (nsim_dev_port_is_pf(nsim_dev_port))
1006 		err = nsim_init_netdevsim(ns);
1007 	else
1008 		err = nsim_init_netdevsim_vf(ns);
1009 	if (err)
1010 		goto err_free_netdev;
1011 
1012 	ns->pp_dfs = debugfs_create_file("pp_hold", 0600, nsim_dev_port->ddir,
1013 					 ns, &nsim_pp_hold_fops);
1014 	ns->qr_dfs = debugfs_create_file("queue_reset", 0200,
1015 					 nsim_dev_port->ddir, ns,
1016 					 &nsim_qreset_fops);
1017 
1018 	return ns;
1019 
1020 err_free_netdev:
1021 	free_netdev(dev);
1022 	return ERR_PTR(err);
1023 }
1024 
1025 void nsim_destroy(struct netdevsim *ns)
1026 {
1027 	struct net_device *dev = ns->netdev;
1028 	struct netdevsim *peer;
1029 
1030 	debugfs_remove(ns->qr_dfs);
1031 	debugfs_remove(ns->pp_dfs);
1032 
1033 	rtnl_lock();
1034 	peer = rtnl_dereference(ns->peer);
1035 	if (peer)
1036 		RCU_INIT_POINTER(peer->peer, NULL);
1037 	RCU_INIT_POINTER(ns->peer, NULL);
1038 	unregister_netdevice(dev);
1039 	if (nsim_dev_port_is_pf(ns->nsim_dev_port)) {
1040 		nsim_macsec_teardown(ns);
1041 		nsim_ipsec_teardown(ns);
1042 		nsim_bpf_uninit(ns);
1043 		nsim_queue_uninit(ns);
1044 	}
1045 	rtnl_unlock();
1046 	if (nsim_dev_port_is_pf(ns->nsim_dev_port))
1047 		nsim_exit_netdevsim(ns);
1048 
1049 	/* Put this intentionally late to exercise the orphaning path */
1050 	if (ns->page) {
1051 		page_pool_put_full_page(ns->page->pp, ns->page, false);
1052 		ns->page = NULL;
1053 	}
1054 
1055 	free_netdev(dev);
1056 }
1057 
1058 bool netdev_is_nsim(struct net_device *dev)
1059 {
1060 	return dev->netdev_ops == &nsim_netdev_ops;
1061 }
1062 
1063 static int nsim_validate(struct nlattr *tb[], struct nlattr *data[],
1064 			 struct netlink_ext_ack *extack)
1065 {
1066 	NL_SET_ERR_MSG_MOD(extack,
1067 			   "Please use: echo \"[ID] [PORT_COUNT] [NUM_QUEUES]\" > /sys/bus/netdevsim/new_device");
1068 	return -EOPNOTSUPP;
1069 }
1070 
1071 static struct rtnl_link_ops nsim_link_ops __read_mostly = {
1072 	.kind		= DRV_NAME,
1073 	.validate	= nsim_validate,
1074 };
1075 
1076 static int __init nsim_module_init(void)
1077 {
1078 	int err;
1079 
1080 	err = nsim_dev_init();
1081 	if (err)
1082 		return err;
1083 
1084 	err = nsim_bus_init();
1085 	if (err)
1086 		goto err_dev_exit;
1087 
1088 	err = rtnl_link_register(&nsim_link_ops);
1089 	if (err)
1090 		goto err_bus_exit;
1091 
1092 	return 0;
1093 
1094 err_bus_exit:
1095 	nsim_bus_exit();
1096 err_dev_exit:
1097 	nsim_dev_exit();
1098 	return err;
1099 }
1100 
1101 static void __exit nsim_module_exit(void)
1102 {
1103 	rtnl_link_unregister(&nsim_link_ops);
1104 	nsim_bus_exit();
1105 	nsim_dev_exit();
1106 }
1107 
1108 module_init(nsim_module_init);
1109 module_exit(nsim_module_exit);
1110 MODULE_LICENSE("GPL");
1111 MODULE_DESCRIPTION("Simulated networking device for testing");
1112 MODULE_ALIAS_RTNL_LINK(DRV_NAME);
1113