xref: /openbmc/linux/drivers/net/hyperv/netvsc_drv.c (revision 53df89dd)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2009, Microsoft Corporation.
4  *
5  * Authors:
6  *   Haiyang Zhang <haiyangz@microsoft.com>
7  *   Hank Janssen  <hjanssen@microsoft.com>
8  */
9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10 
11 #include <linux/init.h>
12 #include <linux/atomic.h>
13 #include <linux/ethtool.h>
14 #include <linux/module.h>
15 #include <linux/highmem.h>
16 #include <linux/device.h>
17 #include <linux/io.h>
18 #include <linux/delay.h>
19 #include <linux/netdevice.h>
20 #include <linux/inetdevice.h>
21 #include <linux/etherdevice.h>
22 #include <linux/pci.h>
23 #include <linux/skbuff.h>
24 #include <linux/if_vlan.h>
25 #include <linux/in.h>
26 #include <linux/slab.h>
27 #include <linux/rtnetlink.h>
28 #include <linux/netpoll.h>
29 #include <linux/bpf.h>
30 
31 #include <net/arp.h>
32 #include <net/route.h>
33 #include <net/sock.h>
34 #include <net/pkt_sched.h>
35 #include <net/checksum.h>
36 #include <net/ip6_checksum.h>
37 
38 #include "hyperv_net.h"
39 
40 #define RING_SIZE_MIN	64
41 #define RETRY_US_LO	5000
42 #define RETRY_US_HI	10000
43 #define RETRY_MAX	2000	/* >10 sec */
44 
45 #define LINKCHANGE_INT (2 * HZ)
46 #define VF_TAKEOVER_INT (HZ / 10)
47 
48 static unsigned int ring_size __ro_after_init = 128;
49 module_param(ring_size, uint, 0444);
50 MODULE_PARM_DESC(ring_size, "Ring buffer size (# of pages)");
51 unsigned int netvsc_ring_bytes __ro_after_init;
52 
53 static const u32 default_msg = NETIF_MSG_DRV | NETIF_MSG_PROBE |
54 				NETIF_MSG_LINK | NETIF_MSG_IFUP |
55 				NETIF_MSG_IFDOWN | NETIF_MSG_RX_ERR |
56 				NETIF_MSG_TX_ERR;
57 
58 static int debug = -1;
59 module_param(debug, int, 0444);
60 MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
61 
62 static LIST_HEAD(netvsc_dev_list);
63 
64 static void netvsc_change_rx_flags(struct net_device *net, int change)
65 {
66 	struct net_device_context *ndev_ctx = netdev_priv(net);
67 	struct net_device *vf_netdev = rtnl_dereference(ndev_ctx->vf_netdev);
68 	int inc;
69 
70 	if (!vf_netdev)
71 		return;
72 
73 	if (change & IFF_PROMISC) {
74 		inc = (net->flags & IFF_PROMISC) ? 1 : -1;
75 		dev_set_promiscuity(vf_netdev, inc);
76 	}
77 
78 	if (change & IFF_ALLMULTI) {
79 		inc = (net->flags & IFF_ALLMULTI) ? 1 : -1;
80 		dev_set_allmulti(vf_netdev, inc);
81 	}
82 }
83 
84 static void netvsc_set_rx_mode(struct net_device *net)
85 {
86 	struct net_device_context *ndev_ctx = netdev_priv(net);
87 	struct net_device *vf_netdev;
88 	struct netvsc_device *nvdev;
89 
90 	rcu_read_lock();
91 	vf_netdev = rcu_dereference(ndev_ctx->vf_netdev);
92 	if (vf_netdev) {
93 		dev_uc_sync(vf_netdev, net);
94 		dev_mc_sync(vf_netdev, net);
95 	}
96 
97 	nvdev = rcu_dereference(ndev_ctx->nvdev);
98 	if (nvdev)
99 		rndis_filter_update(nvdev);
100 	rcu_read_unlock();
101 }
102 
103 static void netvsc_tx_enable(struct netvsc_device *nvscdev,
104 			     struct net_device *ndev)
105 {
106 	nvscdev->tx_disable = false;
107 	virt_wmb(); /* ensure queue wake up mechanism is on */
108 
109 	netif_tx_wake_all_queues(ndev);
110 }
111 
112 static int netvsc_open(struct net_device *net)
113 {
114 	struct net_device_context *ndev_ctx = netdev_priv(net);
115 	struct net_device *vf_netdev = rtnl_dereference(ndev_ctx->vf_netdev);
116 	struct netvsc_device *nvdev = rtnl_dereference(ndev_ctx->nvdev);
117 	struct rndis_device *rdev;
118 	int ret = 0;
119 
120 	netif_carrier_off(net);
121 
122 	/* Open up the device */
123 	ret = rndis_filter_open(nvdev);
124 	if (ret != 0) {
125 		netdev_err(net, "unable to open device (ret %d).\n", ret);
126 		return ret;
127 	}
128 
129 	rdev = nvdev->extension;
130 	if (!rdev->link_state) {
131 		netif_carrier_on(net);
132 		netvsc_tx_enable(nvdev, net);
133 	}
134 
135 	if (vf_netdev) {
136 		/* Setting synthetic device up transparently sets
137 		 * slave as up. If open fails, then slave will be
138 		 * still be offline (and not used).
139 		 */
140 		ret = dev_open(vf_netdev, NULL);
141 		if (ret)
142 			netdev_warn(net,
143 				    "unable to open slave: %s: %d\n",
144 				    vf_netdev->name, ret);
145 	}
146 	return 0;
147 }
148 
149 static int netvsc_wait_until_empty(struct netvsc_device *nvdev)
150 {
151 	unsigned int retry = 0;
152 	int i;
153 
154 	/* Ensure pending bytes in ring are read */
155 	for (;;) {
156 		u32 aread = 0;
157 
158 		for (i = 0; i < nvdev->num_chn; i++) {
159 			struct vmbus_channel *chn
160 				= nvdev->chan_table[i].channel;
161 
162 			if (!chn)
163 				continue;
164 
165 			/* make sure receive not running now */
166 			napi_synchronize(&nvdev->chan_table[i].napi);
167 
168 			aread = hv_get_bytes_to_read(&chn->inbound);
169 			if (aread)
170 				break;
171 
172 			aread = hv_get_bytes_to_read(&chn->outbound);
173 			if (aread)
174 				break;
175 		}
176 
177 		if (aread == 0)
178 			return 0;
179 
180 		if (++retry > RETRY_MAX)
181 			return -ETIMEDOUT;
182 
183 		usleep_range(RETRY_US_LO, RETRY_US_HI);
184 	}
185 }
186 
187 static void netvsc_tx_disable(struct netvsc_device *nvscdev,
188 			      struct net_device *ndev)
189 {
190 	if (nvscdev) {
191 		nvscdev->tx_disable = true;
192 		virt_wmb(); /* ensure txq will not wake up after stop */
193 	}
194 
195 	netif_tx_disable(ndev);
196 }
197 
198 static int netvsc_close(struct net_device *net)
199 {
200 	struct net_device_context *net_device_ctx = netdev_priv(net);
201 	struct net_device *vf_netdev
202 		= rtnl_dereference(net_device_ctx->vf_netdev);
203 	struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
204 	int ret;
205 
206 	netvsc_tx_disable(nvdev, net);
207 
208 	/* No need to close rndis filter if it is removed already */
209 	if (!nvdev)
210 		return 0;
211 
212 	ret = rndis_filter_close(nvdev);
213 	if (ret != 0) {
214 		netdev_err(net, "unable to close device (ret %d).\n", ret);
215 		return ret;
216 	}
217 
218 	ret = netvsc_wait_until_empty(nvdev);
219 	if (ret)
220 		netdev_err(net, "Ring buffer not empty after closing rndis\n");
221 
222 	if (vf_netdev)
223 		dev_close(vf_netdev);
224 
225 	return ret;
226 }
227 
228 static inline void *init_ppi_data(struct rndis_message *msg,
229 				  u32 ppi_size, u32 pkt_type)
230 {
231 	struct rndis_packet *rndis_pkt = &msg->msg.pkt;
232 	struct rndis_per_packet_info *ppi;
233 
234 	rndis_pkt->data_offset += ppi_size;
235 	ppi = (void *)rndis_pkt + rndis_pkt->per_pkt_info_offset
236 		+ rndis_pkt->per_pkt_info_len;
237 
238 	ppi->size = ppi_size;
239 	ppi->type = pkt_type;
240 	ppi->internal = 0;
241 	ppi->ppi_offset = sizeof(struct rndis_per_packet_info);
242 
243 	rndis_pkt->per_pkt_info_len += ppi_size;
244 
245 	return ppi + 1;
246 }
247 
248 /* Azure hosts don't support non-TCP port numbers in hashing for fragmented
249  * packets. We can use ethtool to change UDP hash level when necessary.
250  */
251 static inline u32 netvsc_get_hash(
252 	struct sk_buff *skb,
253 	const struct net_device_context *ndc)
254 {
255 	struct flow_keys flow;
256 	u32 hash, pkt_proto = 0;
257 	static u32 hashrnd __read_mostly;
258 
259 	net_get_random_once(&hashrnd, sizeof(hashrnd));
260 
261 	if (!skb_flow_dissect_flow_keys(skb, &flow, 0))
262 		return 0;
263 
264 	switch (flow.basic.ip_proto) {
265 	case IPPROTO_TCP:
266 		if (flow.basic.n_proto == htons(ETH_P_IP))
267 			pkt_proto = HV_TCP4_L4HASH;
268 		else if (flow.basic.n_proto == htons(ETH_P_IPV6))
269 			pkt_proto = HV_TCP6_L4HASH;
270 
271 		break;
272 
273 	case IPPROTO_UDP:
274 		if (flow.basic.n_proto == htons(ETH_P_IP))
275 			pkt_proto = HV_UDP4_L4HASH;
276 		else if (flow.basic.n_proto == htons(ETH_P_IPV6))
277 			pkt_proto = HV_UDP6_L4HASH;
278 
279 		break;
280 	}
281 
282 	if (pkt_proto & ndc->l4_hash) {
283 		return skb_get_hash(skb);
284 	} else {
285 		if (flow.basic.n_proto == htons(ETH_P_IP))
286 			hash = jhash2((u32 *)&flow.addrs.v4addrs, 2, hashrnd);
287 		else if (flow.basic.n_proto == htons(ETH_P_IPV6))
288 			hash = jhash2((u32 *)&flow.addrs.v6addrs, 8, hashrnd);
289 		else
290 			return 0;
291 
292 		__skb_set_sw_hash(skb, hash, false);
293 	}
294 
295 	return hash;
296 }
297 
298 static inline int netvsc_get_tx_queue(struct net_device *ndev,
299 				      struct sk_buff *skb, int old_idx)
300 {
301 	const struct net_device_context *ndc = netdev_priv(ndev);
302 	struct sock *sk = skb->sk;
303 	int q_idx;
304 
305 	q_idx = ndc->tx_table[netvsc_get_hash(skb, ndc) &
306 			      (VRSS_SEND_TAB_SIZE - 1)];
307 
308 	/* If queue index changed record the new value */
309 	if (q_idx != old_idx &&
310 	    sk && sk_fullsock(sk) && rcu_access_pointer(sk->sk_dst_cache))
311 		sk_tx_queue_set(sk, q_idx);
312 
313 	return q_idx;
314 }
315 
316 /*
317  * Select queue for transmit.
318  *
319  * If a valid queue has already been assigned, then use that.
320  * Otherwise compute tx queue based on hash and the send table.
321  *
322  * This is basically similar to default (netdev_pick_tx) with the added step
323  * of using the host send_table when no other queue has been assigned.
324  *
325  * TODO support XPS - but get_xps_queue not exported
326  */
327 static u16 netvsc_pick_tx(struct net_device *ndev, struct sk_buff *skb)
328 {
329 	int q_idx = sk_tx_queue_get(skb->sk);
330 
331 	if (q_idx < 0 || skb->ooo_okay || q_idx >= ndev->real_num_tx_queues) {
332 		/* If forwarding a packet, we use the recorded queue when
333 		 * available for better cache locality.
334 		 */
335 		if (skb_rx_queue_recorded(skb))
336 			q_idx = skb_get_rx_queue(skb);
337 		else
338 			q_idx = netvsc_get_tx_queue(ndev, skb, q_idx);
339 	}
340 
341 	return q_idx;
342 }
343 
344 static u16 netvsc_select_queue(struct net_device *ndev, struct sk_buff *skb,
345 			       struct net_device *sb_dev)
346 {
347 	struct net_device_context *ndc = netdev_priv(ndev);
348 	struct net_device *vf_netdev;
349 	u16 txq;
350 
351 	rcu_read_lock();
352 	vf_netdev = rcu_dereference(ndc->vf_netdev);
353 	if (vf_netdev) {
354 		const struct net_device_ops *vf_ops = vf_netdev->netdev_ops;
355 
356 		if (vf_ops->ndo_select_queue)
357 			txq = vf_ops->ndo_select_queue(vf_netdev, skb, sb_dev);
358 		else
359 			txq = netdev_pick_tx(vf_netdev, skb, NULL);
360 
361 		/* Record the queue selected by VF so that it can be
362 		 * used for common case where VF has more queues than
363 		 * the synthetic device.
364 		 */
365 		qdisc_skb_cb(skb)->slave_dev_queue_mapping = txq;
366 	} else {
367 		txq = netvsc_pick_tx(ndev, skb);
368 	}
369 	rcu_read_unlock();
370 
371 	while (txq >= ndev->real_num_tx_queues)
372 		txq -= ndev->real_num_tx_queues;
373 
374 	return txq;
375 }
376 
377 static u32 fill_pg_buf(unsigned long hvpfn, u32 offset, u32 len,
378 		       struct hv_page_buffer *pb)
379 {
380 	int j = 0;
381 
382 	hvpfn += offset >> HV_HYP_PAGE_SHIFT;
383 	offset = offset & ~HV_HYP_PAGE_MASK;
384 
385 	while (len > 0) {
386 		unsigned long bytes;
387 
388 		bytes = HV_HYP_PAGE_SIZE - offset;
389 		if (bytes > len)
390 			bytes = len;
391 		pb[j].pfn = hvpfn;
392 		pb[j].offset = offset;
393 		pb[j].len = bytes;
394 
395 		offset += bytes;
396 		len -= bytes;
397 
398 		if (offset == HV_HYP_PAGE_SIZE && len) {
399 			hvpfn++;
400 			offset = 0;
401 			j++;
402 		}
403 	}
404 
405 	return j + 1;
406 }
407 
408 static u32 init_page_array(void *hdr, u32 len, struct sk_buff *skb,
409 			   struct hv_netvsc_packet *packet,
410 			   struct hv_page_buffer *pb)
411 {
412 	u32 slots_used = 0;
413 	char *data = skb->data;
414 	int frags = skb_shinfo(skb)->nr_frags;
415 	int i;
416 
417 	/* The packet is laid out thus:
418 	 * 1. hdr: RNDIS header and PPI
419 	 * 2. skb linear data
420 	 * 3. skb fragment data
421 	 */
422 	slots_used += fill_pg_buf(virt_to_hvpfn(hdr),
423 				  offset_in_hvpage(hdr),
424 				  len,
425 				  &pb[slots_used]);
426 
427 	packet->rmsg_size = len;
428 	packet->rmsg_pgcnt = slots_used;
429 
430 	slots_used += fill_pg_buf(virt_to_hvpfn(data),
431 				  offset_in_hvpage(data),
432 				  skb_headlen(skb),
433 				  &pb[slots_used]);
434 
435 	for (i = 0; i < frags; i++) {
436 		skb_frag_t *frag = skb_shinfo(skb)->frags + i;
437 
438 		slots_used += fill_pg_buf(page_to_hvpfn(skb_frag_page(frag)),
439 					  skb_frag_off(frag),
440 					  skb_frag_size(frag),
441 					  &pb[slots_used]);
442 	}
443 	return slots_used;
444 }
445 
446 static int count_skb_frag_slots(struct sk_buff *skb)
447 {
448 	int i, frags = skb_shinfo(skb)->nr_frags;
449 	int pages = 0;
450 
451 	for (i = 0; i < frags; i++) {
452 		skb_frag_t *frag = skb_shinfo(skb)->frags + i;
453 		unsigned long size = skb_frag_size(frag);
454 		unsigned long offset = skb_frag_off(frag);
455 
456 		/* Skip unused frames from start of page */
457 		offset &= ~HV_HYP_PAGE_MASK;
458 		pages += HVPFN_UP(offset + size);
459 	}
460 	return pages;
461 }
462 
463 static int netvsc_get_slots(struct sk_buff *skb)
464 {
465 	char *data = skb->data;
466 	unsigned int offset = offset_in_hvpage(data);
467 	unsigned int len = skb_headlen(skb);
468 	int slots;
469 	int frag_slots;
470 
471 	slots = DIV_ROUND_UP(offset + len, HV_HYP_PAGE_SIZE);
472 	frag_slots = count_skb_frag_slots(skb);
473 	return slots + frag_slots;
474 }
475 
476 static u32 net_checksum_info(struct sk_buff *skb)
477 {
478 	if (skb->protocol == htons(ETH_P_IP)) {
479 		struct iphdr *ip = ip_hdr(skb);
480 
481 		if (ip->protocol == IPPROTO_TCP)
482 			return TRANSPORT_INFO_IPV4_TCP;
483 		else if (ip->protocol == IPPROTO_UDP)
484 			return TRANSPORT_INFO_IPV4_UDP;
485 	} else {
486 		struct ipv6hdr *ip6 = ipv6_hdr(skb);
487 
488 		if (ip6->nexthdr == IPPROTO_TCP)
489 			return TRANSPORT_INFO_IPV6_TCP;
490 		else if (ip6->nexthdr == IPPROTO_UDP)
491 			return TRANSPORT_INFO_IPV6_UDP;
492 	}
493 
494 	return TRANSPORT_INFO_NOT_IP;
495 }
496 
497 /* Send skb on the slave VF device. */
498 static int netvsc_vf_xmit(struct net_device *net, struct net_device *vf_netdev,
499 			  struct sk_buff *skb)
500 {
501 	struct net_device_context *ndev_ctx = netdev_priv(net);
502 	unsigned int len = skb->len;
503 	int rc;
504 
505 	skb->dev = vf_netdev;
506 	skb_record_rx_queue(skb, qdisc_skb_cb(skb)->slave_dev_queue_mapping);
507 
508 	rc = dev_queue_xmit(skb);
509 	if (likely(rc == NET_XMIT_SUCCESS || rc == NET_XMIT_CN)) {
510 		struct netvsc_vf_pcpu_stats *pcpu_stats
511 			= this_cpu_ptr(ndev_ctx->vf_stats);
512 
513 		u64_stats_update_begin(&pcpu_stats->syncp);
514 		pcpu_stats->tx_packets++;
515 		pcpu_stats->tx_bytes += len;
516 		u64_stats_update_end(&pcpu_stats->syncp);
517 	} else {
518 		this_cpu_inc(ndev_ctx->vf_stats->tx_dropped);
519 	}
520 
521 	return rc;
522 }
523 
524 static int netvsc_xmit(struct sk_buff *skb, struct net_device *net, bool xdp_tx)
525 {
526 	struct net_device_context *net_device_ctx = netdev_priv(net);
527 	struct hv_netvsc_packet *packet = NULL;
528 	int ret;
529 	unsigned int num_data_pgs;
530 	struct rndis_message *rndis_msg;
531 	struct net_device *vf_netdev;
532 	u32 rndis_msg_size;
533 	u32 hash;
534 	struct hv_page_buffer pb[MAX_PAGE_BUFFER_COUNT];
535 
536 	/* If VF is present and up then redirect packets to it.
537 	 * Skip the VF if it is marked down or has no carrier.
538 	 * If netpoll is in uses, then VF can not be used either.
539 	 */
540 	vf_netdev = rcu_dereference_bh(net_device_ctx->vf_netdev);
541 	if (vf_netdev && netif_running(vf_netdev) &&
542 	    netif_carrier_ok(vf_netdev) && !netpoll_tx_running(net) &&
543 	    net_device_ctx->data_path_is_vf)
544 		return netvsc_vf_xmit(net, vf_netdev, skb);
545 
546 	/* We will atmost need two pages to describe the rndis
547 	 * header. We can only transmit MAX_PAGE_BUFFER_COUNT number
548 	 * of pages in a single packet. If skb is scattered around
549 	 * more pages we try linearizing it.
550 	 */
551 
552 	num_data_pgs = netvsc_get_slots(skb) + 2;
553 
554 	if (unlikely(num_data_pgs > MAX_PAGE_BUFFER_COUNT)) {
555 		++net_device_ctx->eth_stats.tx_scattered;
556 
557 		if (skb_linearize(skb))
558 			goto no_memory;
559 
560 		num_data_pgs = netvsc_get_slots(skb) + 2;
561 		if (num_data_pgs > MAX_PAGE_BUFFER_COUNT) {
562 			++net_device_ctx->eth_stats.tx_too_big;
563 			goto drop;
564 		}
565 	}
566 
567 	/*
568 	 * Place the rndis header in the skb head room and
569 	 * the skb->cb will be used for hv_netvsc_packet
570 	 * structure.
571 	 */
572 	ret = skb_cow_head(skb, RNDIS_AND_PPI_SIZE);
573 	if (ret)
574 		goto no_memory;
575 
576 	/* Use the skb control buffer for building up the packet */
577 	BUILD_BUG_ON(sizeof(struct hv_netvsc_packet) >
578 			sizeof_field(struct sk_buff, cb));
579 	packet = (struct hv_netvsc_packet *)skb->cb;
580 
581 	packet->q_idx = skb_get_queue_mapping(skb);
582 
583 	packet->total_data_buflen = skb->len;
584 	packet->total_bytes = skb->len;
585 	packet->total_packets = 1;
586 
587 	rndis_msg = (struct rndis_message *)skb->head;
588 
589 	/* Add the rndis header */
590 	rndis_msg->ndis_msg_type = RNDIS_MSG_PACKET;
591 	rndis_msg->msg_len = packet->total_data_buflen;
592 
593 	rndis_msg->msg.pkt = (struct rndis_packet) {
594 		.data_offset = sizeof(struct rndis_packet),
595 		.data_len = packet->total_data_buflen,
596 		.per_pkt_info_offset = sizeof(struct rndis_packet),
597 	};
598 
599 	rndis_msg_size = RNDIS_MESSAGE_SIZE(struct rndis_packet);
600 
601 	hash = skb_get_hash_raw(skb);
602 	if (hash != 0 && net->real_num_tx_queues > 1) {
603 		u32 *hash_info;
604 
605 		rndis_msg_size += NDIS_HASH_PPI_SIZE;
606 		hash_info = init_ppi_data(rndis_msg, NDIS_HASH_PPI_SIZE,
607 					  NBL_HASH_VALUE);
608 		*hash_info = hash;
609 	}
610 
611 	/* When using AF_PACKET we need to drop VLAN header from
612 	 * the frame and update the SKB to allow the HOST OS
613 	 * to transmit the 802.1Q packet
614 	 */
615 	if (skb->protocol == htons(ETH_P_8021Q)) {
616 		u16 vlan_tci;
617 
618 		skb_reset_mac_header(skb);
619 		if (eth_type_vlan(eth_hdr(skb)->h_proto)) {
620 			if (unlikely(__skb_vlan_pop(skb, &vlan_tci) != 0)) {
621 				++net_device_ctx->eth_stats.vlan_error;
622 				goto drop;
623 			}
624 
625 			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tci);
626 			/* Update the NDIS header pkt lengths */
627 			packet->total_data_buflen -= VLAN_HLEN;
628 			packet->total_bytes -= VLAN_HLEN;
629 			rndis_msg->msg_len = packet->total_data_buflen;
630 			rndis_msg->msg.pkt.data_len = packet->total_data_buflen;
631 		}
632 	}
633 
634 	if (skb_vlan_tag_present(skb)) {
635 		struct ndis_pkt_8021q_info *vlan;
636 
637 		rndis_msg_size += NDIS_VLAN_PPI_SIZE;
638 		vlan = init_ppi_data(rndis_msg, NDIS_VLAN_PPI_SIZE,
639 				     IEEE_8021Q_INFO);
640 
641 		vlan->value = 0;
642 		vlan->vlanid = skb_vlan_tag_get_id(skb);
643 		vlan->cfi = skb_vlan_tag_get_cfi(skb);
644 		vlan->pri = skb_vlan_tag_get_prio(skb);
645 	}
646 
647 	if (skb_is_gso(skb)) {
648 		struct ndis_tcp_lso_info *lso_info;
649 
650 		rndis_msg_size += NDIS_LSO_PPI_SIZE;
651 		lso_info = init_ppi_data(rndis_msg, NDIS_LSO_PPI_SIZE,
652 					 TCP_LARGESEND_PKTINFO);
653 
654 		lso_info->value = 0;
655 		lso_info->lso_v2_transmit.type = NDIS_TCP_LARGE_SEND_OFFLOAD_V2_TYPE;
656 		if (skb->protocol == htons(ETH_P_IP)) {
657 			lso_info->lso_v2_transmit.ip_version =
658 				NDIS_TCP_LARGE_SEND_OFFLOAD_IPV4;
659 			ip_hdr(skb)->tot_len = 0;
660 			ip_hdr(skb)->check = 0;
661 			tcp_hdr(skb)->check =
662 				~csum_tcpudp_magic(ip_hdr(skb)->saddr,
663 						   ip_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
664 		} else {
665 			lso_info->lso_v2_transmit.ip_version =
666 				NDIS_TCP_LARGE_SEND_OFFLOAD_IPV6;
667 			tcp_v6_gso_csum_prep(skb);
668 		}
669 		lso_info->lso_v2_transmit.tcp_header_offset = skb_transport_offset(skb);
670 		lso_info->lso_v2_transmit.mss = skb_shinfo(skb)->gso_size;
671 	} else if (skb->ip_summed == CHECKSUM_PARTIAL) {
672 		if (net_checksum_info(skb) & net_device_ctx->tx_checksum_mask) {
673 			struct ndis_tcp_ip_checksum_info *csum_info;
674 
675 			rndis_msg_size += NDIS_CSUM_PPI_SIZE;
676 			csum_info = init_ppi_data(rndis_msg, NDIS_CSUM_PPI_SIZE,
677 						  TCPIP_CHKSUM_PKTINFO);
678 
679 			csum_info->value = 0;
680 			csum_info->transmit.tcp_header_offset = skb_transport_offset(skb);
681 
682 			if (skb->protocol == htons(ETH_P_IP)) {
683 				csum_info->transmit.is_ipv4 = 1;
684 
685 				if (ip_hdr(skb)->protocol == IPPROTO_TCP)
686 					csum_info->transmit.tcp_checksum = 1;
687 				else
688 					csum_info->transmit.udp_checksum = 1;
689 			} else {
690 				csum_info->transmit.is_ipv6 = 1;
691 
692 				if (ipv6_hdr(skb)->nexthdr == IPPROTO_TCP)
693 					csum_info->transmit.tcp_checksum = 1;
694 				else
695 					csum_info->transmit.udp_checksum = 1;
696 			}
697 		} else {
698 			/* Can't do offload of this type of checksum */
699 			if (skb_checksum_help(skb))
700 				goto drop;
701 		}
702 	}
703 
704 	/* Start filling in the page buffers with the rndis hdr */
705 	rndis_msg->msg_len += rndis_msg_size;
706 	packet->total_data_buflen = rndis_msg->msg_len;
707 	packet->page_buf_cnt = init_page_array(rndis_msg, rndis_msg_size,
708 					       skb, packet, pb);
709 
710 	/* timestamp packet in software */
711 	skb_tx_timestamp(skb);
712 
713 	ret = netvsc_send(net, packet, rndis_msg, pb, skb, xdp_tx);
714 	if (likely(ret == 0))
715 		return NETDEV_TX_OK;
716 
717 	if (ret == -EAGAIN) {
718 		++net_device_ctx->eth_stats.tx_busy;
719 		return NETDEV_TX_BUSY;
720 	}
721 
722 	if (ret == -ENOSPC)
723 		++net_device_ctx->eth_stats.tx_no_space;
724 
725 drop:
726 	dev_kfree_skb_any(skb);
727 	net->stats.tx_dropped++;
728 
729 	return NETDEV_TX_OK;
730 
731 no_memory:
732 	++net_device_ctx->eth_stats.tx_no_memory;
733 	goto drop;
734 }
735 
736 static netdev_tx_t netvsc_start_xmit(struct sk_buff *skb,
737 				     struct net_device *ndev)
738 {
739 	return netvsc_xmit(skb, ndev, false);
740 }
741 
742 /*
743  * netvsc_linkstatus_callback - Link up/down notification
744  */
745 void netvsc_linkstatus_callback(struct net_device *net,
746 				struct rndis_message *resp,
747 				void *data, u32 data_buflen)
748 {
749 	struct rndis_indicate_status *indicate = &resp->msg.indicate_status;
750 	struct net_device_context *ndev_ctx = netdev_priv(net);
751 	struct netvsc_reconfig *event;
752 	unsigned long flags;
753 
754 	/* Ensure the packet is big enough to access its fields */
755 	if (resp->msg_len - RNDIS_HEADER_SIZE < sizeof(struct rndis_indicate_status)) {
756 		netdev_err(net, "invalid rndis_indicate_status packet, len: %u\n",
757 			   resp->msg_len);
758 		return;
759 	}
760 
761 	/* Copy the RNDIS indicate status into nvchan->recv_buf */
762 	memcpy(indicate, data + RNDIS_HEADER_SIZE, sizeof(*indicate));
763 
764 	/* Update the physical link speed when changing to another vSwitch */
765 	if (indicate->status == RNDIS_STATUS_LINK_SPEED_CHANGE) {
766 		u32 speed;
767 
768 		/* Validate status_buf_offset and status_buflen.
769 		 *
770 		 * Certain (pre-Fe) implementations of Hyper-V's vSwitch didn't account
771 		 * for the status buffer field in resp->msg_len; perform the validation
772 		 * using data_buflen (>= resp->msg_len).
773 		 */
774 		if (indicate->status_buflen < sizeof(speed) ||
775 		    indicate->status_buf_offset < sizeof(*indicate) ||
776 		    data_buflen - RNDIS_HEADER_SIZE < indicate->status_buf_offset ||
777 		    data_buflen - RNDIS_HEADER_SIZE - indicate->status_buf_offset
778 				< indicate->status_buflen) {
779 			netdev_err(net, "invalid rndis_indicate_status packet\n");
780 			return;
781 		}
782 
783 		speed = *(u32 *)(data + RNDIS_HEADER_SIZE + indicate->status_buf_offset) / 10000;
784 		ndev_ctx->speed = speed;
785 		return;
786 	}
787 
788 	/* Handle these link change statuses below */
789 	if (indicate->status != RNDIS_STATUS_NETWORK_CHANGE &&
790 	    indicate->status != RNDIS_STATUS_MEDIA_CONNECT &&
791 	    indicate->status != RNDIS_STATUS_MEDIA_DISCONNECT)
792 		return;
793 
794 	if (net->reg_state != NETREG_REGISTERED)
795 		return;
796 
797 	event = kzalloc(sizeof(*event), GFP_ATOMIC);
798 	if (!event)
799 		return;
800 	event->event = indicate->status;
801 
802 	spin_lock_irqsave(&ndev_ctx->lock, flags);
803 	list_add_tail(&event->list, &ndev_ctx->reconfig_events);
804 	spin_unlock_irqrestore(&ndev_ctx->lock, flags);
805 
806 	schedule_delayed_work(&ndev_ctx->dwork, 0);
807 }
808 
809 static void netvsc_xdp_xmit(struct sk_buff *skb, struct net_device *ndev)
810 {
811 	int rc;
812 
813 	skb->queue_mapping = skb_get_rx_queue(skb);
814 	__skb_push(skb, ETH_HLEN);
815 
816 	rc = netvsc_xmit(skb, ndev, true);
817 
818 	if (dev_xmit_complete(rc))
819 		return;
820 
821 	dev_kfree_skb_any(skb);
822 	ndev->stats.tx_dropped++;
823 }
824 
825 static void netvsc_comp_ipcsum(struct sk_buff *skb)
826 {
827 	struct iphdr *iph = (struct iphdr *)skb->data;
828 
829 	iph->check = 0;
830 	iph->check = ip_fast_csum(iph, iph->ihl);
831 }
832 
833 static struct sk_buff *netvsc_alloc_recv_skb(struct net_device *net,
834 					     struct netvsc_channel *nvchan,
835 					     struct xdp_buff *xdp)
836 {
837 	struct napi_struct *napi = &nvchan->napi;
838 	const struct ndis_pkt_8021q_info *vlan = &nvchan->rsc.vlan;
839 	const struct ndis_tcp_ip_checksum_info *csum_info =
840 						&nvchan->rsc.csum_info;
841 	const u32 *hash_info = &nvchan->rsc.hash_info;
842 	u8 ppi_flags = nvchan->rsc.ppi_flags;
843 	struct sk_buff *skb;
844 	void *xbuf = xdp->data_hard_start;
845 	int i;
846 
847 	if (xbuf) {
848 		unsigned int hdroom = xdp->data - xdp->data_hard_start;
849 		unsigned int xlen = xdp->data_end - xdp->data;
850 		unsigned int frag_size = xdp->frame_sz;
851 
852 		skb = build_skb(xbuf, frag_size);
853 
854 		if (!skb) {
855 			__free_page(virt_to_page(xbuf));
856 			return NULL;
857 		}
858 
859 		skb_reserve(skb, hdroom);
860 		skb_put(skb, xlen);
861 		skb->dev = napi->dev;
862 	} else {
863 		skb = napi_alloc_skb(napi, nvchan->rsc.pktlen);
864 
865 		if (!skb)
866 			return NULL;
867 
868 		/* Copy to skb. This copy is needed here since the memory
869 		 * pointed by hv_netvsc_packet cannot be deallocated.
870 		 */
871 		for (i = 0; i < nvchan->rsc.cnt; i++)
872 			skb_put_data(skb, nvchan->rsc.data[i],
873 				     nvchan->rsc.len[i]);
874 	}
875 
876 	skb->protocol = eth_type_trans(skb, net);
877 
878 	/* skb is already created with CHECKSUM_NONE */
879 	skb_checksum_none_assert(skb);
880 
881 	/* Incoming packets may have IP header checksum verified by the host.
882 	 * They may not have IP header checksum computed after coalescing.
883 	 * We compute it here if the flags are set, because on Linux, the IP
884 	 * checksum is always checked.
885 	 */
886 	if ((ppi_flags & NVSC_RSC_CSUM_INFO) && csum_info->receive.ip_checksum_value_invalid &&
887 	    csum_info->receive.ip_checksum_succeeded &&
888 	    skb->protocol == htons(ETH_P_IP)) {
889 		/* Check that there is enough space to hold the IP header. */
890 		if (skb_headlen(skb) < sizeof(struct iphdr)) {
891 			kfree_skb(skb);
892 			return NULL;
893 		}
894 		netvsc_comp_ipcsum(skb);
895 	}
896 
897 	/* Do L4 checksum offload if enabled and present. */
898 	if ((ppi_flags & NVSC_RSC_CSUM_INFO) && (net->features & NETIF_F_RXCSUM)) {
899 		if (csum_info->receive.tcp_checksum_succeeded ||
900 		    csum_info->receive.udp_checksum_succeeded)
901 			skb->ip_summed = CHECKSUM_UNNECESSARY;
902 	}
903 
904 	if ((ppi_flags & NVSC_RSC_HASH_INFO) && (net->features & NETIF_F_RXHASH))
905 		skb_set_hash(skb, *hash_info, PKT_HASH_TYPE_L4);
906 
907 	if (ppi_flags & NVSC_RSC_VLAN) {
908 		u16 vlan_tci = vlan->vlanid | (vlan->pri << VLAN_PRIO_SHIFT) |
909 			(vlan->cfi ? VLAN_CFI_MASK : 0);
910 
911 		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
912 				       vlan_tci);
913 	}
914 
915 	return skb;
916 }
917 
918 /*
919  * netvsc_recv_callback -  Callback when we receive a packet from the
920  * "wire" on the specified device.
921  */
922 int netvsc_recv_callback(struct net_device *net,
923 			 struct netvsc_device *net_device,
924 			 struct netvsc_channel *nvchan)
925 {
926 	struct net_device_context *net_device_ctx = netdev_priv(net);
927 	struct vmbus_channel *channel = nvchan->channel;
928 	u16 q_idx = channel->offermsg.offer.sub_channel_index;
929 	struct sk_buff *skb;
930 	struct netvsc_stats *rx_stats = &nvchan->rx_stats;
931 	struct xdp_buff xdp;
932 	u32 act;
933 
934 	if (net->reg_state != NETREG_REGISTERED)
935 		return NVSP_STAT_FAIL;
936 
937 	act = netvsc_run_xdp(net, nvchan, &xdp);
938 
939 	if (act != XDP_PASS && act != XDP_TX) {
940 		u64_stats_update_begin(&rx_stats->syncp);
941 		rx_stats->xdp_drop++;
942 		u64_stats_update_end(&rx_stats->syncp);
943 
944 		return NVSP_STAT_SUCCESS; /* consumed by XDP */
945 	}
946 
947 	/* Allocate a skb - TODO direct I/O to pages? */
948 	skb = netvsc_alloc_recv_skb(net, nvchan, &xdp);
949 
950 	if (unlikely(!skb)) {
951 		++net_device_ctx->eth_stats.rx_no_memory;
952 		return NVSP_STAT_FAIL;
953 	}
954 
955 	skb_record_rx_queue(skb, q_idx);
956 
957 	/*
958 	 * Even if injecting the packet, record the statistics
959 	 * on the synthetic device because modifying the VF device
960 	 * statistics will not work correctly.
961 	 */
962 	u64_stats_update_begin(&rx_stats->syncp);
963 	rx_stats->packets++;
964 	rx_stats->bytes += nvchan->rsc.pktlen;
965 
966 	if (skb->pkt_type == PACKET_BROADCAST)
967 		++rx_stats->broadcast;
968 	else if (skb->pkt_type == PACKET_MULTICAST)
969 		++rx_stats->multicast;
970 	u64_stats_update_end(&rx_stats->syncp);
971 
972 	if (act == XDP_TX) {
973 		netvsc_xdp_xmit(skb, net);
974 		return NVSP_STAT_SUCCESS;
975 	}
976 
977 	napi_gro_receive(&nvchan->napi, skb);
978 	return NVSP_STAT_SUCCESS;
979 }
980 
981 static void netvsc_get_drvinfo(struct net_device *net,
982 			       struct ethtool_drvinfo *info)
983 {
984 	strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
985 	strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
986 }
987 
988 static void netvsc_get_channels(struct net_device *net,
989 				struct ethtool_channels *channel)
990 {
991 	struct net_device_context *net_device_ctx = netdev_priv(net);
992 	struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
993 
994 	if (nvdev) {
995 		channel->max_combined	= nvdev->max_chn;
996 		channel->combined_count = nvdev->num_chn;
997 	}
998 }
999 
1000 /* Alloc struct netvsc_device_info, and initialize it from either existing
1001  * struct netvsc_device, or from default values.
1002  */
1003 static
1004 struct netvsc_device_info *netvsc_devinfo_get(struct netvsc_device *nvdev)
1005 {
1006 	struct netvsc_device_info *dev_info;
1007 	struct bpf_prog *prog;
1008 
1009 	dev_info = kzalloc(sizeof(*dev_info), GFP_ATOMIC);
1010 
1011 	if (!dev_info)
1012 		return NULL;
1013 
1014 	if (nvdev) {
1015 		ASSERT_RTNL();
1016 
1017 		dev_info->num_chn = nvdev->num_chn;
1018 		dev_info->send_sections = nvdev->send_section_cnt;
1019 		dev_info->send_section_size = nvdev->send_section_size;
1020 		dev_info->recv_sections = nvdev->recv_section_cnt;
1021 		dev_info->recv_section_size = nvdev->recv_section_size;
1022 
1023 		memcpy(dev_info->rss_key, nvdev->extension->rss_key,
1024 		       NETVSC_HASH_KEYLEN);
1025 
1026 		prog = netvsc_xdp_get(nvdev);
1027 		if (prog) {
1028 			bpf_prog_inc(prog);
1029 			dev_info->bprog = prog;
1030 		}
1031 	} else {
1032 		dev_info->num_chn = VRSS_CHANNEL_DEFAULT;
1033 		dev_info->send_sections = NETVSC_DEFAULT_TX;
1034 		dev_info->send_section_size = NETVSC_SEND_SECTION_SIZE;
1035 		dev_info->recv_sections = NETVSC_DEFAULT_RX;
1036 		dev_info->recv_section_size = NETVSC_RECV_SECTION_SIZE;
1037 	}
1038 
1039 	return dev_info;
1040 }
1041 
1042 /* Free struct netvsc_device_info */
1043 static void netvsc_devinfo_put(struct netvsc_device_info *dev_info)
1044 {
1045 	if (dev_info->bprog) {
1046 		ASSERT_RTNL();
1047 		bpf_prog_put(dev_info->bprog);
1048 	}
1049 
1050 	kfree(dev_info);
1051 }
1052 
1053 static int netvsc_detach(struct net_device *ndev,
1054 			 struct netvsc_device *nvdev)
1055 {
1056 	struct net_device_context *ndev_ctx = netdev_priv(ndev);
1057 	struct hv_device *hdev = ndev_ctx->device_ctx;
1058 	int ret;
1059 
1060 	/* Don't try continuing to try and setup sub channels */
1061 	if (cancel_work_sync(&nvdev->subchan_work))
1062 		nvdev->num_chn = 1;
1063 
1064 	netvsc_xdp_set(ndev, NULL, NULL, nvdev);
1065 
1066 	/* If device was up (receiving) then shutdown */
1067 	if (netif_running(ndev)) {
1068 		netvsc_tx_disable(nvdev, ndev);
1069 
1070 		ret = rndis_filter_close(nvdev);
1071 		if (ret) {
1072 			netdev_err(ndev,
1073 				   "unable to close device (ret %d).\n", ret);
1074 			return ret;
1075 		}
1076 
1077 		ret = netvsc_wait_until_empty(nvdev);
1078 		if (ret) {
1079 			netdev_err(ndev,
1080 				   "Ring buffer not empty after closing rndis\n");
1081 			return ret;
1082 		}
1083 	}
1084 
1085 	netif_device_detach(ndev);
1086 
1087 	rndis_filter_device_remove(hdev, nvdev);
1088 
1089 	return 0;
1090 }
1091 
1092 static int netvsc_attach(struct net_device *ndev,
1093 			 struct netvsc_device_info *dev_info)
1094 {
1095 	struct net_device_context *ndev_ctx = netdev_priv(ndev);
1096 	struct hv_device *hdev = ndev_ctx->device_ctx;
1097 	struct netvsc_device *nvdev;
1098 	struct rndis_device *rdev;
1099 	struct bpf_prog *prog;
1100 	int ret = 0;
1101 
1102 	nvdev = rndis_filter_device_add(hdev, dev_info);
1103 	if (IS_ERR(nvdev))
1104 		return PTR_ERR(nvdev);
1105 
1106 	if (nvdev->num_chn > 1) {
1107 		ret = rndis_set_subchannel(ndev, nvdev, dev_info);
1108 
1109 		/* if unavailable, just proceed with one queue */
1110 		if (ret) {
1111 			nvdev->max_chn = 1;
1112 			nvdev->num_chn = 1;
1113 		}
1114 	}
1115 
1116 	prog = dev_info->bprog;
1117 	if (prog) {
1118 		bpf_prog_inc(prog);
1119 		ret = netvsc_xdp_set(ndev, prog, NULL, nvdev);
1120 		if (ret) {
1121 			bpf_prog_put(prog);
1122 			goto err1;
1123 		}
1124 	}
1125 
1126 	/* In any case device is now ready */
1127 	nvdev->tx_disable = false;
1128 	netif_device_attach(ndev);
1129 
1130 	/* Note: enable and attach happen when sub-channels setup */
1131 	netif_carrier_off(ndev);
1132 
1133 	if (netif_running(ndev)) {
1134 		ret = rndis_filter_open(nvdev);
1135 		if (ret)
1136 			goto err2;
1137 
1138 		rdev = nvdev->extension;
1139 		if (!rdev->link_state)
1140 			netif_carrier_on(ndev);
1141 	}
1142 
1143 	return 0;
1144 
1145 err2:
1146 	netif_device_detach(ndev);
1147 
1148 err1:
1149 	rndis_filter_device_remove(hdev, nvdev);
1150 
1151 	return ret;
1152 }
1153 
1154 static int netvsc_set_channels(struct net_device *net,
1155 			       struct ethtool_channels *channels)
1156 {
1157 	struct net_device_context *net_device_ctx = netdev_priv(net);
1158 	struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
1159 	unsigned int orig, count = channels->combined_count;
1160 	struct netvsc_device_info *device_info;
1161 	int ret;
1162 
1163 	/* We do not support separate count for rx, tx, or other */
1164 	if (count == 0 ||
1165 	    channels->rx_count || channels->tx_count || channels->other_count)
1166 		return -EINVAL;
1167 
1168 	if (!nvdev || nvdev->destroy)
1169 		return -ENODEV;
1170 
1171 	if (nvdev->nvsp_version < NVSP_PROTOCOL_VERSION_5)
1172 		return -EINVAL;
1173 
1174 	if (count > nvdev->max_chn)
1175 		return -EINVAL;
1176 
1177 	orig = nvdev->num_chn;
1178 
1179 	device_info = netvsc_devinfo_get(nvdev);
1180 
1181 	if (!device_info)
1182 		return -ENOMEM;
1183 
1184 	device_info->num_chn = count;
1185 
1186 	ret = netvsc_detach(net, nvdev);
1187 	if (ret)
1188 		goto out;
1189 
1190 	ret = netvsc_attach(net, device_info);
1191 	if (ret) {
1192 		device_info->num_chn = orig;
1193 		if (netvsc_attach(net, device_info))
1194 			netdev_err(net, "restoring channel setting failed\n");
1195 	}
1196 
1197 out:
1198 	netvsc_devinfo_put(device_info);
1199 	return ret;
1200 }
1201 
1202 static void netvsc_init_settings(struct net_device *dev)
1203 {
1204 	struct net_device_context *ndc = netdev_priv(dev);
1205 
1206 	ndc->l4_hash = HV_DEFAULT_L4HASH;
1207 
1208 	ndc->speed = SPEED_UNKNOWN;
1209 	ndc->duplex = DUPLEX_FULL;
1210 
1211 	dev->features = NETIF_F_LRO;
1212 }
1213 
1214 static int netvsc_get_link_ksettings(struct net_device *dev,
1215 				     struct ethtool_link_ksettings *cmd)
1216 {
1217 	struct net_device_context *ndc = netdev_priv(dev);
1218 	struct net_device *vf_netdev;
1219 
1220 	vf_netdev = rtnl_dereference(ndc->vf_netdev);
1221 
1222 	if (vf_netdev)
1223 		return __ethtool_get_link_ksettings(vf_netdev, cmd);
1224 
1225 	cmd->base.speed = ndc->speed;
1226 	cmd->base.duplex = ndc->duplex;
1227 	cmd->base.port = PORT_OTHER;
1228 
1229 	return 0;
1230 }
1231 
1232 static int netvsc_set_link_ksettings(struct net_device *dev,
1233 				     const struct ethtool_link_ksettings *cmd)
1234 {
1235 	struct net_device_context *ndc = netdev_priv(dev);
1236 	struct net_device *vf_netdev = rtnl_dereference(ndc->vf_netdev);
1237 
1238 	if (vf_netdev) {
1239 		if (!vf_netdev->ethtool_ops->set_link_ksettings)
1240 			return -EOPNOTSUPP;
1241 
1242 		return vf_netdev->ethtool_ops->set_link_ksettings(vf_netdev,
1243 								  cmd);
1244 	}
1245 
1246 	return ethtool_virtdev_set_link_ksettings(dev, cmd,
1247 						  &ndc->speed, &ndc->duplex);
1248 }
1249 
1250 static int netvsc_change_mtu(struct net_device *ndev, int mtu)
1251 {
1252 	struct net_device_context *ndevctx = netdev_priv(ndev);
1253 	struct net_device *vf_netdev = rtnl_dereference(ndevctx->vf_netdev);
1254 	struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
1255 	int orig_mtu = ndev->mtu;
1256 	struct netvsc_device_info *device_info;
1257 	int ret = 0;
1258 
1259 	if (!nvdev || nvdev->destroy)
1260 		return -ENODEV;
1261 
1262 	device_info = netvsc_devinfo_get(nvdev);
1263 
1264 	if (!device_info)
1265 		return -ENOMEM;
1266 
1267 	/* Change MTU of underlying VF netdev first. */
1268 	if (vf_netdev) {
1269 		ret = dev_set_mtu(vf_netdev, mtu);
1270 		if (ret)
1271 			goto out;
1272 	}
1273 
1274 	ret = netvsc_detach(ndev, nvdev);
1275 	if (ret)
1276 		goto rollback_vf;
1277 
1278 	ndev->mtu = mtu;
1279 
1280 	ret = netvsc_attach(ndev, device_info);
1281 	if (!ret)
1282 		goto out;
1283 
1284 	/* Attempt rollback to original MTU */
1285 	ndev->mtu = orig_mtu;
1286 
1287 	if (netvsc_attach(ndev, device_info))
1288 		netdev_err(ndev, "restoring mtu failed\n");
1289 rollback_vf:
1290 	if (vf_netdev)
1291 		dev_set_mtu(vf_netdev, orig_mtu);
1292 
1293 out:
1294 	netvsc_devinfo_put(device_info);
1295 	return ret;
1296 }
1297 
1298 static void netvsc_get_vf_stats(struct net_device *net,
1299 				struct netvsc_vf_pcpu_stats *tot)
1300 {
1301 	struct net_device_context *ndev_ctx = netdev_priv(net);
1302 	int i;
1303 
1304 	memset(tot, 0, sizeof(*tot));
1305 
1306 	for_each_possible_cpu(i) {
1307 		const struct netvsc_vf_pcpu_stats *stats
1308 			= per_cpu_ptr(ndev_ctx->vf_stats, i);
1309 		u64 rx_packets, rx_bytes, tx_packets, tx_bytes;
1310 		unsigned int start;
1311 
1312 		do {
1313 			start = u64_stats_fetch_begin_irq(&stats->syncp);
1314 			rx_packets = stats->rx_packets;
1315 			tx_packets = stats->tx_packets;
1316 			rx_bytes = stats->rx_bytes;
1317 			tx_bytes = stats->tx_bytes;
1318 		} while (u64_stats_fetch_retry_irq(&stats->syncp, start));
1319 
1320 		tot->rx_packets += rx_packets;
1321 		tot->tx_packets += tx_packets;
1322 		tot->rx_bytes   += rx_bytes;
1323 		tot->tx_bytes   += tx_bytes;
1324 		tot->tx_dropped += stats->tx_dropped;
1325 	}
1326 }
1327 
1328 static void netvsc_get_pcpu_stats(struct net_device *net,
1329 				  struct netvsc_ethtool_pcpu_stats *pcpu_tot)
1330 {
1331 	struct net_device_context *ndev_ctx = netdev_priv(net);
1332 	struct netvsc_device *nvdev = rcu_dereference_rtnl(ndev_ctx->nvdev);
1333 	int i;
1334 
1335 	/* fetch percpu stats of vf */
1336 	for_each_possible_cpu(i) {
1337 		const struct netvsc_vf_pcpu_stats *stats =
1338 			per_cpu_ptr(ndev_ctx->vf_stats, i);
1339 		struct netvsc_ethtool_pcpu_stats *this_tot = &pcpu_tot[i];
1340 		unsigned int start;
1341 
1342 		do {
1343 			start = u64_stats_fetch_begin_irq(&stats->syncp);
1344 			this_tot->vf_rx_packets = stats->rx_packets;
1345 			this_tot->vf_tx_packets = stats->tx_packets;
1346 			this_tot->vf_rx_bytes = stats->rx_bytes;
1347 			this_tot->vf_tx_bytes = stats->tx_bytes;
1348 		} while (u64_stats_fetch_retry_irq(&stats->syncp, start));
1349 		this_tot->rx_packets = this_tot->vf_rx_packets;
1350 		this_tot->tx_packets = this_tot->vf_tx_packets;
1351 		this_tot->rx_bytes   = this_tot->vf_rx_bytes;
1352 		this_tot->tx_bytes   = this_tot->vf_tx_bytes;
1353 	}
1354 
1355 	/* fetch percpu stats of netvsc */
1356 	for (i = 0; i < nvdev->num_chn; i++) {
1357 		const struct netvsc_channel *nvchan = &nvdev->chan_table[i];
1358 		const struct netvsc_stats *stats;
1359 		struct netvsc_ethtool_pcpu_stats *this_tot =
1360 			&pcpu_tot[nvchan->channel->target_cpu];
1361 		u64 packets, bytes;
1362 		unsigned int start;
1363 
1364 		stats = &nvchan->tx_stats;
1365 		do {
1366 			start = u64_stats_fetch_begin_irq(&stats->syncp);
1367 			packets = stats->packets;
1368 			bytes = stats->bytes;
1369 		} while (u64_stats_fetch_retry_irq(&stats->syncp, start));
1370 
1371 		this_tot->tx_bytes	+= bytes;
1372 		this_tot->tx_packets	+= packets;
1373 
1374 		stats = &nvchan->rx_stats;
1375 		do {
1376 			start = u64_stats_fetch_begin_irq(&stats->syncp);
1377 			packets = stats->packets;
1378 			bytes = stats->bytes;
1379 		} while (u64_stats_fetch_retry_irq(&stats->syncp, start));
1380 
1381 		this_tot->rx_bytes	+= bytes;
1382 		this_tot->rx_packets	+= packets;
1383 	}
1384 }
1385 
1386 static void netvsc_get_stats64(struct net_device *net,
1387 			       struct rtnl_link_stats64 *t)
1388 {
1389 	struct net_device_context *ndev_ctx = netdev_priv(net);
1390 	struct netvsc_device *nvdev;
1391 	struct netvsc_vf_pcpu_stats vf_tot;
1392 	int i;
1393 
1394 	rcu_read_lock();
1395 
1396 	nvdev = rcu_dereference(ndev_ctx->nvdev);
1397 	if (!nvdev)
1398 		goto out;
1399 
1400 	netdev_stats_to_stats64(t, &net->stats);
1401 
1402 	netvsc_get_vf_stats(net, &vf_tot);
1403 	t->rx_packets += vf_tot.rx_packets;
1404 	t->tx_packets += vf_tot.tx_packets;
1405 	t->rx_bytes   += vf_tot.rx_bytes;
1406 	t->tx_bytes   += vf_tot.tx_bytes;
1407 	t->tx_dropped += vf_tot.tx_dropped;
1408 
1409 	for (i = 0; i < nvdev->num_chn; i++) {
1410 		const struct netvsc_channel *nvchan = &nvdev->chan_table[i];
1411 		const struct netvsc_stats *stats;
1412 		u64 packets, bytes, multicast;
1413 		unsigned int start;
1414 
1415 		stats = &nvchan->tx_stats;
1416 		do {
1417 			start = u64_stats_fetch_begin_irq(&stats->syncp);
1418 			packets = stats->packets;
1419 			bytes = stats->bytes;
1420 		} while (u64_stats_fetch_retry_irq(&stats->syncp, start));
1421 
1422 		t->tx_bytes	+= bytes;
1423 		t->tx_packets	+= packets;
1424 
1425 		stats = &nvchan->rx_stats;
1426 		do {
1427 			start = u64_stats_fetch_begin_irq(&stats->syncp);
1428 			packets = stats->packets;
1429 			bytes = stats->bytes;
1430 			multicast = stats->multicast + stats->broadcast;
1431 		} while (u64_stats_fetch_retry_irq(&stats->syncp, start));
1432 
1433 		t->rx_bytes	+= bytes;
1434 		t->rx_packets	+= packets;
1435 		t->multicast	+= multicast;
1436 	}
1437 out:
1438 	rcu_read_unlock();
1439 }
1440 
1441 static int netvsc_set_mac_addr(struct net_device *ndev, void *p)
1442 {
1443 	struct net_device_context *ndc = netdev_priv(ndev);
1444 	struct net_device *vf_netdev = rtnl_dereference(ndc->vf_netdev);
1445 	struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
1446 	struct sockaddr *addr = p;
1447 	int err;
1448 
1449 	err = eth_prepare_mac_addr_change(ndev, p);
1450 	if (err)
1451 		return err;
1452 
1453 	if (!nvdev)
1454 		return -ENODEV;
1455 
1456 	if (vf_netdev) {
1457 		err = dev_set_mac_address(vf_netdev, addr, NULL);
1458 		if (err)
1459 			return err;
1460 	}
1461 
1462 	err = rndis_filter_set_device_mac(nvdev, addr->sa_data);
1463 	if (!err) {
1464 		eth_commit_mac_addr_change(ndev, p);
1465 	} else if (vf_netdev) {
1466 		/* rollback change on VF */
1467 		memcpy(addr->sa_data, ndev->dev_addr, ETH_ALEN);
1468 		dev_set_mac_address(vf_netdev, addr, NULL);
1469 	}
1470 
1471 	return err;
1472 }
1473 
1474 static const struct {
1475 	char name[ETH_GSTRING_LEN];
1476 	u16 offset;
1477 } netvsc_stats[] = {
1478 	{ "tx_scattered", offsetof(struct netvsc_ethtool_stats, tx_scattered) },
1479 	{ "tx_no_memory", offsetof(struct netvsc_ethtool_stats, tx_no_memory) },
1480 	{ "tx_no_space",  offsetof(struct netvsc_ethtool_stats, tx_no_space) },
1481 	{ "tx_too_big",	  offsetof(struct netvsc_ethtool_stats, tx_too_big) },
1482 	{ "tx_busy",	  offsetof(struct netvsc_ethtool_stats, tx_busy) },
1483 	{ "tx_send_full", offsetof(struct netvsc_ethtool_stats, tx_send_full) },
1484 	{ "rx_comp_busy", offsetof(struct netvsc_ethtool_stats, rx_comp_busy) },
1485 	{ "rx_no_memory", offsetof(struct netvsc_ethtool_stats, rx_no_memory) },
1486 	{ "stop_queue", offsetof(struct netvsc_ethtool_stats, stop_queue) },
1487 	{ "wake_queue", offsetof(struct netvsc_ethtool_stats, wake_queue) },
1488 	{ "vlan_error", offsetof(struct netvsc_ethtool_stats, vlan_error) },
1489 }, pcpu_stats[] = {
1490 	{ "cpu%u_rx_packets",
1491 		offsetof(struct netvsc_ethtool_pcpu_stats, rx_packets) },
1492 	{ "cpu%u_rx_bytes",
1493 		offsetof(struct netvsc_ethtool_pcpu_stats, rx_bytes) },
1494 	{ "cpu%u_tx_packets",
1495 		offsetof(struct netvsc_ethtool_pcpu_stats, tx_packets) },
1496 	{ "cpu%u_tx_bytes",
1497 		offsetof(struct netvsc_ethtool_pcpu_stats, tx_bytes) },
1498 	{ "cpu%u_vf_rx_packets",
1499 		offsetof(struct netvsc_ethtool_pcpu_stats, vf_rx_packets) },
1500 	{ "cpu%u_vf_rx_bytes",
1501 		offsetof(struct netvsc_ethtool_pcpu_stats, vf_rx_bytes) },
1502 	{ "cpu%u_vf_tx_packets",
1503 		offsetof(struct netvsc_ethtool_pcpu_stats, vf_tx_packets) },
1504 	{ "cpu%u_vf_tx_bytes",
1505 		offsetof(struct netvsc_ethtool_pcpu_stats, vf_tx_bytes) },
1506 }, vf_stats[] = {
1507 	{ "vf_rx_packets", offsetof(struct netvsc_vf_pcpu_stats, rx_packets) },
1508 	{ "vf_rx_bytes",   offsetof(struct netvsc_vf_pcpu_stats, rx_bytes) },
1509 	{ "vf_tx_packets", offsetof(struct netvsc_vf_pcpu_stats, tx_packets) },
1510 	{ "vf_tx_bytes",   offsetof(struct netvsc_vf_pcpu_stats, tx_bytes) },
1511 	{ "vf_tx_dropped", offsetof(struct netvsc_vf_pcpu_stats, tx_dropped) },
1512 };
1513 
1514 #define NETVSC_GLOBAL_STATS_LEN	ARRAY_SIZE(netvsc_stats)
1515 #define NETVSC_VF_STATS_LEN	ARRAY_SIZE(vf_stats)
1516 
1517 /* statistics per queue (rx/tx packets/bytes) */
1518 #define NETVSC_PCPU_STATS_LEN (num_present_cpus() * ARRAY_SIZE(pcpu_stats))
1519 
1520 /* 5 statistics per queue (rx/tx packets/bytes, rx xdp_drop) */
1521 #define NETVSC_QUEUE_STATS_LEN(dev) ((dev)->num_chn * 5)
1522 
1523 static int netvsc_get_sset_count(struct net_device *dev, int string_set)
1524 {
1525 	struct net_device_context *ndc = netdev_priv(dev);
1526 	struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
1527 
1528 	if (!nvdev)
1529 		return -ENODEV;
1530 
1531 	switch (string_set) {
1532 	case ETH_SS_STATS:
1533 		return NETVSC_GLOBAL_STATS_LEN
1534 			+ NETVSC_VF_STATS_LEN
1535 			+ NETVSC_QUEUE_STATS_LEN(nvdev)
1536 			+ NETVSC_PCPU_STATS_LEN;
1537 	default:
1538 		return -EINVAL;
1539 	}
1540 }
1541 
1542 static void netvsc_get_ethtool_stats(struct net_device *dev,
1543 				     struct ethtool_stats *stats, u64 *data)
1544 {
1545 	struct net_device_context *ndc = netdev_priv(dev);
1546 	struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
1547 	const void *nds = &ndc->eth_stats;
1548 	const struct netvsc_stats *qstats;
1549 	struct netvsc_vf_pcpu_stats sum;
1550 	struct netvsc_ethtool_pcpu_stats *pcpu_sum;
1551 	unsigned int start;
1552 	u64 packets, bytes;
1553 	u64 xdp_drop;
1554 	int i, j, cpu;
1555 
1556 	if (!nvdev)
1557 		return;
1558 
1559 	for (i = 0; i < NETVSC_GLOBAL_STATS_LEN; i++)
1560 		data[i] = *(unsigned long *)(nds + netvsc_stats[i].offset);
1561 
1562 	netvsc_get_vf_stats(dev, &sum);
1563 	for (j = 0; j < NETVSC_VF_STATS_LEN; j++)
1564 		data[i++] = *(u64 *)((void *)&sum + vf_stats[j].offset);
1565 
1566 	for (j = 0; j < nvdev->num_chn; j++) {
1567 		qstats = &nvdev->chan_table[j].tx_stats;
1568 
1569 		do {
1570 			start = u64_stats_fetch_begin_irq(&qstats->syncp);
1571 			packets = qstats->packets;
1572 			bytes = qstats->bytes;
1573 		} while (u64_stats_fetch_retry_irq(&qstats->syncp, start));
1574 		data[i++] = packets;
1575 		data[i++] = bytes;
1576 
1577 		qstats = &nvdev->chan_table[j].rx_stats;
1578 		do {
1579 			start = u64_stats_fetch_begin_irq(&qstats->syncp);
1580 			packets = qstats->packets;
1581 			bytes = qstats->bytes;
1582 			xdp_drop = qstats->xdp_drop;
1583 		} while (u64_stats_fetch_retry_irq(&qstats->syncp, start));
1584 		data[i++] = packets;
1585 		data[i++] = bytes;
1586 		data[i++] = xdp_drop;
1587 	}
1588 
1589 	pcpu_sum = kvmalloc_array(num_possible_cpus(),
1590 				  sizeof(struct netvsc_ethtool_pcpu_stats),
1591 				  GFP_KERNEL);
1592 	netvsc_get_pcpu_stats(dev, pcpu_sum);
1593 	for_each_present_cpu(cpu) {
1594 		struct netvsc_ethtool_pcpu_stats *this_sum = &pcpu_sum[cpu];
1595 
1596 		for (j = 0; j < ARRAY_SIZE(pcpu_stats); j++)
1597 			data[i++] = *(u64 *)((void *)this_sum
1598 					     + pcpu_stats[j].offset);
1599 	}
1600 	kvfree(pcpu_sum);
1601 }
1602 
1603 static void netvsc_get_strings(struct net_device *dev, u32 stringset, u8 *data)
1604 {
1605 	struct net_device_context *ndc = netdev_priv(dev);
1606 	struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
1607 	u8 *p = data;
1608 	int i, cpu;
1609 
1610 	if (!nvdev)
1611 		return;
1612 
1613 	switch (stringset) {
1614 	case ETH_SS_STATS:
1615 		for (i = 0; i < ARRAY_SIZE(netvsc_stats); i++) {
1616 			memcpy(p, netvsc_stats[i].name, ETH_GSTRING_LEN);
1617 			p += ETH_GSTRING_LEN;
1618 		}
1619 
1620 		for (i = 0; i < ARRAY_SIZE(vf_stats); i++) {
1621 			memcpy(p, vf_stats[i].name, ETH_GSTRING_LEN);
1622 			p += ETH_GSTRING_LEN;
1623 		}
1624 
1625 		for (i = 0; i < nvdev->num_chn; i++) {
1626 			sprintf(p, "tx_queue_%u_packets", i);
1627 			p += ETH_GSTRING_LEN;
1628 			sprintf(p, "tx_queue_%u_bytes", i);
1629 			p += ETH_GSTRING_LEN;
1630 			sprintf(p, "rx_queue_%u_packets", i);
1631 			p += ETH_GSTRING_LEN;
1632 			sprintf(p, "rx_queue_%u_bytes", i);
1633 			p += ETH_GSTRING_LEN;
1634 			sprintf(p, "rx_queue_%u_xdp_drop", i);
1635 			p += ETH_GSTRING_LEN;
1636 		}
1637 
1638 		for_each_present_cpu(cpu) {
1639 			for (i = 0; i < ARRAY_SIZE(pcpu_stats); i++) {
1640 				sprintf(p, pcpu_stats[i].name, cpu);
1641 				p += ETH_GSTRING_LEN;
1642 			}
1643 		}
1644 
1645 		break;
1646 	}
1647 }
1648 
1649 static int
1650 netvsc_get_rss_hash_opts(struct net_device_context *ndc,
1651 			 struct ethtool_rxnfc *info)
1652 {
1653 	const u32 l4_flag = RXH_L4_B_0_1 | RXH_L4_B_2_3;
1654 
1655 	info->data = RXH_IP_SRC | RXH_IP_DST;
1656 
1657 	switch (info->flow_type) {
1658 	case TCP_V4_FLOW:
1659 		if (ndc->l4_hash & HV_TCP4_L4HASH)
1660 			info->data |= l4_flag;
1661 
1662 		break;
1663 
1664 	case TCP_V6_FLOW:
1665 		if (ndc->l4_hash & HV_TCP6_L4HASH)
1666 			info->data |= l4_flag;
1667 
1668 		break;
1669 
1670 	case UDP_V4_FLOW:
1671 		if (ndc->l4_hash & HV_UDP4_L4HASH)
1672 			info->data |= l4_flag;
1673 
1674 		break;
1675 
1676 	case UDP_V6_FLOW:
1677 		if (ndc->l4_hash & HV_UDP6_L4HASH)
1678 			info->data |= l4_flag;
1679 
1680 		break;
1681 
1682 	case IPV4_FLOW:
1683 	case IPV6_FLOW:
1684 		break;
1685 	default:
1686 		info->data = 0;
1687 		break;
1688 	}
1689 
1690 	return 0;
1691 }
1692 
1693 static int
1694 netvsc_get_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info,
1695 		 u32 *rules)
1696 {
1697 	struct net_device_context *ndc = netdev_priv(dev);
1698 	struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
1699 
1700 	if (!nvdev)
1701 		return -ENODEV;
1702 
1703 	switch (info->cmd) {
1704 	case ETHTOOL_GRXRINGS:
1705 		info->data = nvdev->num_chn;
1706 		return 0;
1707 
1708 	case ETHTOOL_GRXFH:
1709 		return netvsc_get_rss_hash_opts(ndc, info);
1710 	}
1711 	return -EOPNOTSUPP;
1712 }
1713 
1714 static int netvsc_set_rss_hash_opts(struct net_device_context *ndc,
1715 				    struct ethtool_rxnfc *info)
1716 {
1717 	if (info->data == (RXH_IP_SRC | RXH_IP_DST |
1718 			   RXH_L4_B_0_1 | RXH_L4_B_2_3)) {
1719 		switch (info->flow_type) {
1720 		case TCP_V4_FLOW:
1721 			ndc->l4_hash |= HV_TCP4_L4HASH;
1722 			break;
1723 
1724 		case TCP_V6_FLOW:
1725 			ndc->l4_hash |= HV_TCP6_L4HASH;
1726 			break;
1727 
1728 		case UDP_V4_FLOW:
1729 			ndc->l4_hash |= HV_UDP4_L4HASH;
1730 			break;
1731 
1732 		case UDP_V6_FLOW:
1733 			ndc->l4_hash |= HV_UDP6_L4HASH;
1734 			break;
1735 
1736 		default:
1737 			return -EOPNOTSUPP;
1738 		}
1739 
1740 		return 0;
1741 	}
1742 
1743 	if (info->data == (RXH_IP_SRC | RXH_IP_DST)) {
1744 		switch (info->flow_type) {
1745 		case TCP_V4_FLOW:
1746 			ndc->l4_hash &= ~HV_TCP4_L4HASH;
1747 			break;
1748 
1749 		case TCP_V6_FLOW:
1750 			ndc->l4_hash &= ~HV_TCP6_L4HASH;
1751 			break;
1752 
1753 		case UDP_V4_FLOW:
1754 			ndc->l4_hash &= ~HV_UDP4_L4HASH;
1755 			break;
1756 
1757 		case UDP_V6_FLOW:
1758 			ndc->l4_hash &= ~HV_UDP6_L4HASH;
1759 			break;
1760 
1761 		default:
1762 			return -EOPNOTSUPP;
1763 		}
1764 
1765 		return 0;
1766 	}
1767 
1768 	return -EOPNOTSUPP;
1769 }
1770 
1771 static int
1772 netvsc_set_rxnfc(struct net_device *ndev, struct ethtool_rxnfc *info)
1773 {
1774 	struct net_device_context *ndc = netdev_priv(ndev);
1775 
1776 	if (info->cmd == ETHTOOL_SRXFH)
1777 		return netvsc_set_rss_hash_opts(ndc, info);
1778 
1779 	return -EOPNOTSUPP;
1780 }
1781 
1782 static u32 netvsc_get_rxfh_key_size(struct net_device *dev)
1783 {
1784 	return NETVSC_HASH_KEYLEN;
1785 }
1786 
1787 static u32 netvsc_rss_indir_size(struct net_device *dev)
1788 {
1789 	return ITAB_NUM;
1790 }
1791 
1792 static int netvsc_get_rxfh(struct net_device *dev, u32 *indir, u8 *key,
1793 			   u8 *hfunc)
1794 {
1795 	struct net_device_context *ndc = netdev_priv(dev);
1796 	struct netvsc_device *ndev = rtnl_dereference(ndc->nvdev);
1797 	struct rndis_device *rndis_dev;
1798 	int i;
1799 
1800 	if (!ndev)
1801 		return -ENODEV;
1802 
1803 	if (hfunc)
1804 		*hfunc = ETH_RSS_HASH_TOP;	/* Toeplitz */
1805 
1806 	rndis_dev = ndev->extension;
1807 	if (indir) {
1808 		for (i = 0; i < ITAB_NUM; i++)
1809 			indir[i] = ndc->rx_table[i];
1810 	}
1811 
1812 	if (key)
1813 		memcpy(key, rndis_dev->rss_key, NETVSC_HASH_KEYLEN);
1814 
1815 	return 0;
1816 }
1817 
1818 static int netvsc_set_rxfh(struct net_device *dev, const u32 *indir,
1819 			   const u8 *key, const u8 hfunc)
1820 {
1821 	struct net_device_context *ndc = netdev_priv(dev);
1822 	struct netvsc_device *ndev = rtnl_dereference(ndc->nvdev);
1823 	struct rndis_device *rndis_dev;
1824 	int i;
1825 
1826 	if (!ndev)
1827 		return -ENODEV;
1828 
1829 	if (hfunc != ETH_RSS_HASH_NO_CHANGE && hfunc != ETH_RSS_HASH_TOP)
1830 		return -EOPNOTSUPP;
1831 
1832 	rndis_dev = ndev->extension;
1833 	if (indir) {
1834 		for (i = 0; i < ITAB_NUM; i++)
1835 			if (indir[i] >= ndev->num_chn)
1836 				return -EINVAL;
1837 
1838 		for (i = 0; i < ITAB_NUM; i++)
1839 			ndc->rx_table[i] = indir[i];
1840 	}
1841 
1842 	if (!key) {
1843 		if (!indir)
1844 			return 0;
1845 
1846 		key = rndis_dev->rss_key;
1847 	}
1848 
1849 	return rndis_filter_set_rss_param(rndis_dev, key);
1850 }
1851 
1852 /* Hyper-V RNDIS protocol does not have ring in the HW sense.
1853  * It does have pre-allocated receive area which is divided into sections.
1854  */
1855 static void __netvsc_get_ringparam(struct netvsc_device *nvdev,
1856 				   struct ethtool_ringparam *ring)
1857 {
1858 	u32 max_buf_size;
1859 
1860 	ring->rx_pending = nvdev->recv_section_cnt;
1861 	ring->tx_pending = nvdev->send_section_cnt;
1862 
1863 	if (nvdev->nvsp_version <= NVSP_PROTOCOL_VERSION_2)
1864 		max_buf_size = NETVSC_RECEIVE_BUFFER_SIZE_LEGACY;
1865 	else
1866 		max_buf_size = NETVSC_RECEIVE_BUFFER_SIZE;
1867 
1868 	ring->rx_max_pending = max_buf_size / nvdev->recv_section_size;
1869 	ring->tx_max_pending = NETVSC_SEND_BUFFER_SIZE
1870 		/ nvdev->send_section_size;
1871 }
1872 
1873 static void netvsc_get_ringparam(struct net_device *ndev,
1874 				 struct ethtool_ringparam *ring)
1875 {
1876 	struct net_device_context *ndevctx = netdev_priv(ndev);
1877 	struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
1878 
1879 	if (!nvdev)
1880 		return;
1881 
1882 	__netvsc_get_ringparam(nvdev, ring);
1883 }
1884 
1885 static int netvsc_set_ringparam(struct net_device *ndev,
1886 				struct ethtool_ringparam *ring)
1887 {
1888 	struct net_device_context *ndevctx = netdev_priv(ndev);
1889 	struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
1890 	struct netvsc_device_info *device_info;
1891 	struct ethtool_ringparam orig;
1892 	u32 new_tx, new_rx;
1893 	int ret = 0;
1894 
1895 	if (!nvdev || nvdev->destroy)
1896 		return -ENODEV;
1897 
1898 	memset(&orig, 0, sizeof(orig));
1899 	__netvsc_get_ringparam(nvdev, &orig);
1900 
1901 	new_tx = clamp_t(u32, ring->tx_pending,
1902 			 NETVSC_MIN_TX_SECTIONS, orig.tx_max_pending);
1903 	new_rx = clamp_t(u32, ring->rx_pending,
1904 			 NETVSC_MIN_RX_SECTIONS, orig.rx_max_pending);
1905 
1906 	if (new_tx == orig.tx_pending &&
1907 	    new_rx == orig.rx_pending)
1908 		return 0;	 /* no change */
1909 
1910 	device_info = netvsc_devinfo_get(nvdev);
1911 
1912 	if (!device_info)
1913 		return -ENOMEM;
1914 
1915 	device_info->send_sections = new_tx;
1916 	device_info->recv_sections = new_rx;
1917 
1918 	ret = netvsc_detach(ndev, nvdev);
1919 	if (ret)
1920 		goto out;
1921 
1922 	ret = netvsc_attach(ndev, device_info);
1923 	if (ret) {
1924 		device_info->send_sections = orig.tx_pending;
1925 		device_info->recv_sections = orig.rx_pending;
1926 
1927 		if (netvsc_attach(ndev, device_info))
1928 			netdev_err(ndev, "restoring ringparam failed");
1929 	}
1930 
1931 out:
1932 	netvsc_devinfo_put(device_info);
1933 	return ret;
1934 }
1935 
1936 static netdev_features_t netvsc_fix_features(struct net_device *ndev,
1937 					     netdev_features_t features)
1938 {
1939 	struct net_device_context *ndevctx = netdev_priv(ndev);
1940 	struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
1941 
1942 	if (!nvdev || nvdev->destroy)
1943 		return features;
1944 
1945 	if ((features & NETIF_F_LRO) && netvsc_xdp_get(nvdev)) {
1946 		features ^= NETIF_F_LRO;
1947 		netdev_info(ndev, "Skip LRO - unsupported with XDP\n");
1948 	}
1949 
1950 	return features;
1951 }
1952 
1953 static int netvsc_set_features(struct net_device *ndev,
1954 			       netdev_features_t features)
1955 {
1956 	netdev_features_t change = features ^ ndev->features;
1957 	struct net_device_context *ndevctx = netdev_priv(ndev);
1958 	struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
1959 	struct net_device *vf_netdev = rtnl_dereference(ndevctx->vf_netdev);
1960 	struct ndis_offload_params offloads;
1961 	int ret = 0;
1962 
1963 	if (!nvdev || nvdev->destroy)
1964 		return -ENODEV;
1965 
1966 	if (!(change & NETIF_F_LRO))
1967 		goto syncvf;
1968 
1969 	memset(&offloads, 0, sizeof(struct ndis_offload_params));
1970 
1971 	if (features & NETIF_F_LRO) {
1972 		offloads.rsc_ip_v4 = NDIS_OFFLOAD_PARAMETERS_RSC_ENABLED;
1973 		offloads.rsc_ip_v6 = NDIS_OFFLOAD_PARAMETERS_RSC_ENABLED;
1974 	} else {
1975 		offloads.rsc_ip_v4 = NDIS_OFFLOAD_PARAMETERS_RSC_DISABLED;
1976 		offloads.rsc_ip_v6 = NDIS_OFFLOAD_PARAMETERS_RSC_DISABLED;
1977 	}
1978 
1979 	ret = rndis_filter_set_offload_params(ndev, nvdev, &offloads);
1980 
1981 	if (ret) {
1982 		features ^= NETIF_F_LRO;
1983 		ndev->features = features;
1984 	}
1985 
1986 syncvf:
1987 	if (!vf_netdev)
1988 		return ret;
1989 
1990 	vf_netdev->wanted_features = features;
1991 	netdev_update_features(vf_netdev);
1992 
1993 	return ret;
1994 }
1995 
1996 static int netvsc_get_regs_len(struct net_device *netdev)
1997 {
1998 	return VRSS_SEND_TAB_SIZE * sizeof(u32);
1999 }
2000 
2001 static void netvsc_get_regs(struct net_device *netdev,
2002 			    struct ethtool_regs *regs, void *p)
2003 {
2004 	struct net_device_context *ndc = netdev_priv(netdev);
2005 	u32 *regs_buff = p;
2006 
2007 	/* increase the version, if buffer format is changed. */
2008 	regs->version = 1;
2009 
2010 	memcpy(regs_buff, ndc->tx_table, VRSS_SEND_TAB_SIZE * sizeof(u32));
2011 }
2012 
2013 static u32 netvsc_get_msglevel(struct net_device *ndev)
2014 {
2015 	struct net_device_context *ndev_ctx = netdev_priv(ndev);
2016 
2017 	return ndev_ctx->msg_enable;
2018 }
2019 
2020 static void netvsc_set_msglevel(struct net_device *ndev, u32 val)
2021 {
2022 	struct net_device_context *ndev_ctx = netdev_priv(ndev);
2023 
2024 	ndev_ctx->msg_enable = val;
2025 }
2026 
2027 static const struct ethtool_ops ethtool_ops = {
2028 	.get_drvinfo	= netvsc_get_drvinfo,
2029 	.get_regs_len	= netvsc_get_regs_len,
2030 	.get_regs	= netvsc_get_regs,
2031 	.get_msglevel	= netvsc_get_msglevel,
2032 	.set_msglevel	= netvsc_set_msglevel,
2033 	.get_link	= ethtool_op_get_link,
2034 	.get_ethtool_stats = netvsc_get_ethtool_stats,
2035 	.get_sset_count = netvsc_get_sset_count,
2036 	.get_strings	= netvsc_get_strings,
2037 	.get_channels   = netvsc_get_channels,
2038 	.set_channels   = netvsc_set_channels,
2039 	.get_ts_info	= ethtool_op_get_ts_info,
2040 	.get_rxnfc	= netvsc_get_rxnfc,
2041 	.set_rxnfc	= netvsc_set_rxnfc,
2042 	.get_rxfh_key_size = netvsc_get_rxfh_key_size,
2043 	.get_rxfh_indir_size = netvsc_rss_indir_size,
2044 	.get_rxfh	= netvsc_get_rxfh,
2045 	.set_rxfh	= netvsc_set_rxfh,
2046 	.get_link_ksettings = netvsc_get_link_ksettings,
2047 	.set_link_ksettings = netvsc_set_link_ksettings,
2048 	.get_ringparam	= netvsc_get_ringparam,
2049 	.set_ringparam	= netvsc_set_ringparam,
2050 };
2051 
2052 static const struct net_device_ops device_ops = {
2053 	.ndo_open =			netvsc_open,
2054 	.ndo_stop =			netvsc_close,
2055 	.ndo_start_xmit =		netvsc_start_xmit,
2056 	.ndo_change_rx_flags =		netvsc_change_rx_flags,
2057 	.ndo_set_rx_mode =		netvsc_set_rx_mode,
2058 	.ndo_fix_features =		netvsc_fix_features,
2059 	.ndo_set_features =		netvsc_set_features,
2060 	.ndo_change_mtu =		netvsc_change_mtu,
2061 	.ndo_validate_addr =		eth_validate_addr,
2062 	.ndo_set_mac_address =		netvsc_set_mac_addr,
2063 	.ndo_select_queue =		netvsc_select_queue,
2064 	.ndo_get_stats64 =		netvsc_get_stats64,
2065 	.ndo_bpf =			netvsc_bpf,
2066 };
2067 
2068 /*
2069  * Handle link status changes. For RNDIS_STATUS_NETWORK_CHANGE emulate link
2070  * down/up sequence. In case of RNDIS_STATUS_MEDIA_CONNECT when carrier is
2071  * present send GARP packet to network peers with netif_notify_peers().
2072  */
2073 static void netvsc_link_change(struct work_struct *w)
2074 {
2075 	struct net_device_context *ndev_ctx =
2076 		container_of(w, struct net_device_context, dwork.work);
2077 	struct hv_device *device_obj = ndev_ctx->device_ctx;
2078 	struct net_device *net = hv_get_drvdata(device_obj);
2079 	unsigned long flags, next_reconfig, delay;
2080 	struct netvsc_reconfig *event = NULL;
2081 	struct netvsc_device *net_device;
2082 	struct rndis_device *rdev;
2083 	bool reschedule = false;
2084 
2085 	/* if changes are happening, comeback later */
2086 	if (!rtnl_trylock()) {
2087 		schedule_delayed_work(&ndev_ctx->dwork, LINKCHANGE_INT);
2088 		return;
2089 	}
2090 
2091 	net_device = rtnl_dereference(ndev_ctx->nvdev);
2092 	if (!net_device)
2093 		goto out_unlock;
2094 
2095 	rdev = net_device->extension;
2096 
2097 	next_reconfig = ndev_ctx->last_reconfig + LINKCHANGE_INT;
2098 	if (time_is_after_jiffies(next_reconfig)) {
2099 		/* link_watch only sends one notification with current state
2100 		 * per second, avoid doing reconfig more frequently. Handle
2101 		 * wrap around.
2102 		 */
2103 		delay = next_reconfig - jiffies;
2104 		delay = delay < LINKCHANGE_INT ? delay : LINKCHANGE_INT;
2105 		schedule_delayed_work(&ndev_ctx->dwork, delay);
2106 		goto out_unlock;
2107 	}
2108 	ndev_ctx->last_reconfig = jiffies;
2109 
2110 	spin_lock_irqsave(&ndev_ctx->lock, flags);
2111 	if (!list_empty(&ndev_ctx->reconfig_events)) {
2112 		event = list_first_entry(&ndev_ctx->reconfig_events,
2113 					 struct netvsc_reconfig, list);
2114 		list_del(&event->list);
2115 		reschedule = !list_empty(&ndev_ctx->reconfig_events);
2116 	}
2117 	spin_unlock_irqrestore(&ndev_ctx->lock, flags);
2118 
2119 	if (!event)
2120 		goto out_unlock;
2121 
2122 	switch (event->event) {
2123 		/* Only the following events are possible due to the check in
2124 		 * netvsc_linkstatus_callback()
2125 		 */
2126 	case RNDIS_STATUS_MEDIA_CONNECT:
2127 		if (rdev->link_state) {
2128 			rdev->link_state = false;
2129 			netif_carrier_on(net);
2130 			netvsc_tx_enable(net_device, net);
2131 		} else {
2132 			__netdev_notify_peers(net);
2133 		}
2134 		kfree(event);
2135 		break;
2136 	case RNDIS_STATUS_MEDIA_DISCONNECT:
2137 		if (!rdev->link_state) {
2138 			rdev->link_state = true;
2139 			netif_carrier_off(net);
2140 			netvsc_tx_disable(net_device, net);
2141 		}
2142 		kfree(event);
2143 		break;
2144 	case RNDIS_STATUS_NETWORK_CHANGE:
2145 		/* Only makes sense if carrier is present */
2146 		if (!rdev->link_state) {
2147 			rdev->link_state = true;
2148 			netif_carrier_off(net);
2149 			netvsc_tx_disable(net_device, net);
2150 			event->event = RNDIS_STATUS_MEDIA_CONNECT;
2151 			spin_lock_irqsave(&ndev_ctx->lock, flags);
2152 			list_add(&event->list, &ndev_ctx->reconfig_events);
2153 			spin_unlock_irqrestore(&ndev_ctx->lock, flags);
2154 			reschedule = true;
2155 		}
2156 		break;
2157 	}
2158 
2159 	rtnl_unlock();
2160 
2161 	/* link_watch only sends one notification with current state per
2162 	 * second, handle next reconfig event in 2 seconds.
2163 	 */
2164 	if (reschedule)
2165 		schedule_delayed_work(&ndev_ctx->dwork, LINKCHANGE_INT);
2166 
2167 	return;
2168 
2169 out_unlock:
2170 	rtnl_unlock();
2171 }
2172 
2173 static struct net_device *get_netvsc_byref(struct net_device *vf_netdev)
2174 {
2175 	struct net_device_context *net_device_ctx;
2176 	struct net_device *dev;
2177 
2178 	dev = netdev_master_upper_dev_get(vf_netdev);
2179 	if (!dev || dev->netdev_ops != &device_ops)
2180 		return NULL;	/* not a netvsc device */
2181 
2182 	net_device_ctx = netdev_priv(dev);
2183 	if (!rtnl_dereference(net_device_ctx->nvdev))
2184 		return NULL;	/* device is removed */
2185 
2186 	return dev;
2187 }
2188 
2189 /* Called when VF is injecting data into network stack.
2190  * Change the associated network device from VF to netvsc.
2191  * note: already called with rcu_read_lock
2192  */
2193 static rx_handler_result_t netvsc_vf_handle_frame(struct sk_buff **pskb)
2194 {
2195 	struct sk_buff *skb = *pskb;
2196 	struct net_device *ndev = rcu_dereference(skb->dev->rx_handler_data);
2197 	struct net_device_context *ndev_ctx = netdev_priv(ndev);
2198 	struct netvsc_vf_pcpu_stats *pcpu_stats
2199 		 = this_cpu_ptr(ndev_ctx->vf_stats);
2200 
2201 	skb = skb_share_check(skb, GFP_ATOMIC);
2202 	if (unlikely(!skb))
2203 		return RX_HANDLER_CONSUMED;
2204 
2205 	*pskb = skb;
2206 
2207 	skb->dev = ndev;
2208 
2209 	u64_stats_update_begin(&pcpu_stats->syncp);
2210 	pcpu_stats->rx_packets++;
2211 	pcpu_stats->rx_bytes += skb->len;
2212 	u64_stats_update_end(&pcpu_stats->syncp);
2213 
2214 	return RX_HANDLER_ANOTHER;
2215 }
2216 
2217 static int netvsc_vf_join(struct net_device *vf_netdev,
2218 			  struct net_device *ndev)
2219 {
2220 	struct net_device_context *ndev_ctx = netdev_priv(ndev);
2221 	int ret;
2222 
2223 	ret = netdev_rx_handler_register(vf_netdev,
2224 					 netvsc_vf_handle_frame, ndev);
2225 	if (ret != 0) {
2226 		netdev_err(vf_netdev,
2227 			   "can not register netvsc VF receive handler (err = %d)\n",
2228 			   ret);
2229 		goto rx_handler_failed;
2230 	}
2231 
2232 	ret = netdev_master_upper_dev_link(vf_netdev, ndev,
2233 					   NULL, NULL, NULL);
2234 	if (ret != 0) {
2235 		netdev_err(vf_netdev,
2236 			   "can not set master device %s (err = %d)\n",
2237 			   ndev->name, ret);
2238 		goto upper_link_failed;
2239 	}
2240 
2241 	/* set slave flag before open to prevent IPv6 addrconf */
2242 	vf_netdev->flags |= IFF_SLAVE;
2243 
2244 	schedule_delayed_work(&ndev_ctx->vf_takeover, VF_TAKEOVER_INT);
2245 
2246 	call_netdevice_notifiers(NETDEV_JOIN, vf_netdev);
2247 
2248 	netdev_info(vf_netdev, "joined to %s\n", ndev->name);
2249 	return 0;
2250 
2251 upper_link_failed:
2252 	netdev_rx_handler_unregister(vf_netdev);
2253 rx_handler_failed:
2254 	return ret;
2255 }
2256 
2257 static void __netvsc_vf_setup(struct net_device *ndev,
2258 			      struct net_device *vf_netdev)
2259 {
2260 	int ret;
2261 
2262 	/* Align MTU of VF with master */
2263 	ret = dev_set_mtu(vf_netdev, ndev->mtu);
2264 	if (ret)
2265 		netdev_warn(vf_netdev,
2266 			    "unable to change mtu to %u\n", ndev->mtu);
2267 
2268 	/* set multicast etc flags on VF */
2269 	dev_change_flags(vf_netdev, ndev->flags | IFF_SLAVE, NULL);
2270 
2271 	/* sync address list from ndev to VF */
2272 	netif_addr_lock_bh(ndev);
2273 	dev_uc_sync(vf_netdev, ndev);
2274 	dev_mc_sync(vf_netdev, ndev);
2275 	netif_addr_unlock_bh(ndev);
2276 
2277 	if (netif_running(ndev)) {
2278 		ret = dev_open(vf_netdev, NULL);
2279 		if (ret)
2280 			netdev_warn(vf_netdev,
2281 				    "unable to open: %d\n", ret);
2282 	}
2283 }
2284 
2285 /* Setup VF as slave of the synthetic device.
2286  * Runs in workqueue to avoid recursion in netlink callbacks.
2287  */
2288 static void netvsc_vf_setup(struct work_struct *w)
2289 {
2290 	struct net_device_context *ndev_ctx
2291 		= container_of(w, struct net_device_context, vf_takeover.work);
2292 	struct net_device *ndev = hv_get_drvdata(ndev_ctx->device_ctx);
2293 	struct net_device *vf_netdev;
2294 
2295 	if (!rtnl_trylock()) {
2296 		schedule_delayed_work(&ndev_ctx->vf_takeover, 0);
2297 		return;
2298 	}
2299 
2300 	vf_netdev = rtnl_dereference(ndev_ctx->vf_netdev);
2301 	if (vf_netdev)
2302 		__netvsc_vf_setup(ndev, vf_netdev);
2303 
2304 	rtnl_unlock();
2305 }
2306 
2307 /* Find netvsc by VF serial number.
2308  * The PCI hyperv controller records the serial number as the slot kobj name.
2309  */
2310 static struct net_device *get_netvsc_byslot(const struct net_device *vf_netdev)
2311 {
2312 	struct device *parent = vf_netdev->dev.parent;
2313 	struct net_device_context *ndev_ctx;
2314 	struct pci_dev *pdev;
2315 	u32 serial;
2316 
2317 	if (!parent || !dev_is_pci(parent))
2318 		return NULL; /* not a PCI device */
2319 
2320 	pdev = to_pci_dev(parent);
2321 	if (!pdev->slot) {
2322 		netdev_notice(vf_netdev, "no PCI slot information\n");
2323 		return NULL;
2324 	}
2325 
2326 	if (kstrtou32(pci_slot_name(pdev->slot), 10, &serial)) {
2327 		netdev_notice(vf_netdev, "Invalid vf serial:%s\n",
2328 			      pci_slot_name(pdev->slot));
2329 		return NULL;
2330 	}
2331 
2332 	list_for_each_entry(ndev_ctx, &netvsc_dev_list, list) {
2333 		if (!ndev_ctx->vf_alloc)
2334 			continue;
2335 
2336 		if (ndev_ctx->vf_serial == serial)
2337 			return hv_get_drvdata(ndev_ctx->device_ctx);
2338 	}
2339 
2340 	netdev_notice(vf_netdev,
2341 		      "no netdev found for vf serial:%u\n", serial);
2342 	return NULL;
2343 }
2344 
2345 static int netvsc_register_vf(struct net_device *vf_netdev)
2346 {
2347 	struct net_device_context *net_device_ctx;
2348 	struct netvsc_device *netvsc_dev;
2349 	struct bpf_prog *prog;
2350 	struct net_device *ndev;
2351 	int ret;
2352 
2353 	if (vf_netdev->addr_len != ETH_ALEN)
2354 		return NOTIFY_DONE;
2355 
2356 	ndev = get_netvsc_byslot(vf_netdev);
2357 	if (!ndev)
2358 		return NOTIFY_DONE;
2359 
2360 	net_device_ctx = netdev_priv(ndev);
2361 	netvsc_dev = rtnl_dereference(net_device_ctx->nvdev);
2362 	if (!netvsc_dev || rtnl_dereference(net_device_ctx->vf_netdev))
2363 		return NOTIFY_DONE;
2364 
2365 	/* if synthetic interface is a different namespace,
2366 	 * then move the VF to that namespace; join will be
2367 	 * done again in that context.
2368 	 */
2369 	if (!net_eq(dev_net(ndev), dev_net(vf_netdev))) {
2370 		ret = dev_change_net_namespace(vf_netdev,
2371 					       dev_net(ndev), "eth%d");
2372 		if (ret)
2373 			netdev_err(vf_netdev,
2374 				   "could not move to same namespace as %s: %d\n",
2375 				   ndev->name, ret);
2376 		else
2377 			netdev_info(vf_netdev,
2378 				    "VF moved to namespace with: %s\n",
2379 				    ndev->name);
2380 		return NOTIFY_DONE;
2381 	}
2382 
2383 	netdev_info(ndev, "VF registering: %s\n", vf_netdev->name);
2384 
2385 	if (netvsc_vf_join(vf_netdev, ndev) != 0)
2386 		return NOTIFY_DONE;
2387 
2388 	dev_hold(vf_netdev);
2389 	rcu_assign_pointer(net_device_ctx->vf_netdev, vf_netdev);
2390 
2391 	vf_netdev->wanted_features = ndev->features;
2392 	netdev_update_features(vf_netdev);
2393 
2394 	prog = netvsc_xdp_get(netvsc_dev);
2395 	netvsc_vf_setxdp(vf_netdev, prog);
2396 
2397 	return NOTIFY_OK;
2398 }
2399 
2400 /* Change the data path when VF UP/DOWN/CHANGE are detected.
2401  *
2402  * Typically a UP or DOWN event is followed by a CHANGE event, so
2403  * net_device_ctx->data_path_is_vf is used to cache the current data path
2404  * to avoid the duplicate call of netvsc_switch_datapath() and the duplicate
2405  * message.
2406  *
2407  * During hibernation, if a VF NIC driver (e.g. mlx5) preserves the network
2408  * interface, there is only the CHANGE event and no UP or DOWN event.
2409  */
2410 static int netvsc_vf_changed(struct net_device *vf_netdev, unsigned long event)
2411 {
2412 	struct net_device_context *net_device_ctx;
2413 	struct netvsc_device *netvsc_dev;
2414 	struct net_device *ndev;
2415 	bool vf_is_up = false;
2416 
2417 	if (event != NETDEV_GOING_DOWN)
2418 		vf_is_up = netif_running(vf_netdev);
2419 
2420 	ndev = get_netvsc_byref(vf_netdev);
2421 	if (!ndev)
2422 		return NOTIFY_DONE;
2423 
2424 	net_device_ctx = netdev_priv(ndev);
2425 	netvsc_dev = rtnl_dereference(net_device_ctx->nvdev);
2426 	if (!netvsc_dev)
2427 		return NOTIFY_DONE;
2428 
2429 	if (net_device_ctx->data_path_is_vf == vf_is_up)
2430 		return NOTIFY_OK;
2431 
2432 	netvsc_switch_datapath(ndev, vf_is_up);
2433 	netdev_info(ndev, "Data path switched %s VF: %s\n",
2434 		    vf_is_up ? "to" : "from", vf_netdev->name);
2435 
2436 	return NOTIFY_OK;
2437 }
2438 
2439 static int netvsc_unregister_vf(struct net_device *vf_netdev)
2440 {
2441 	struct net_device *ndev;
2442 	struct net_device_context *net_device_ctx;
2443 
2444 	ndev = get_netvsc_byref(vf_netdev);
2445 	if (!ndev)
2446 		return NOTIFY_DONE;
2447 
2448 	net_device_ctx = netdev_priv(ndev);
2449 	cancel_delayed_work_sync(&net_device_ctx->vf_takeover);
2450 
2451 	netdev_info(ndev, "VF unregistering: %s\n", vf_netdev->name);
2452 
2453 	netvsc_vf_setxdp(vf_netdev, NULL);
2454 
2455 	netdev_rx_handler_unregister(vf_netdev);
2456 	netdev_upper_dev_unlink(vf_netdev, ndev);
2457 	RCU_INIT_POINTER(net_device_ctx->vf_netdev, NULL);
2458 	dev_put(vf_netdev);
2459 
2460 	return NOTIFY_OK;
2461 }
2462 
2463 static int netvsc_probe(struct hv_device *dev,
2464 			const struct hv_vmbus_device_id *dev_id)
2465 {
2466 	struct net_device *net = NULL;
2467 	struct net_device_context *net_device_ctx;
2468 	struct netvsc_device_info *device_info = NULL;
2469 	struct netvsc_device *nvdev;
2470 	int ret = -ENOMEM;
2471 
2472 	net = alloc_etherdev_mq(sizeof(struct net_device_context),
2473 				VRSS_CHANNEL_MAX);
2474 	if (!net)
2475 		goto no_net;
2476 
2477 	netif_carrier_off(net);
2478 
2479 	netvsc_init_settings(net);
2480 
2481 	net_device_ctx = netdev_priv(net);
2482 	net_device_ctx->device_ctx = dev;
2483 	net_device_ctx->msg_enable = netif_msg_init(debug, default_msg);
2484 	if (netif_msg_probe(net_device_ctx))
2485 		netdev_dbg(net, "netvsc msg_enable: %d\n",
2486 			   net_device_ctx->msg_enable);
2487 
2488 	hv_set_drvdata(dev, net);
2489 
2490 	INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_link_change);
2491 
2492 	spin_lock_init(&net_device_ctx->lock);
2493 	INIT_LIST_HEAD(&net_device_ctx->reconfig_events);
2494 	INIT_DELAYED_WORK(&net_device_ctx->vf_takeover, netvsc_vf_setup);
2495 
2496 	net_device_ctx->vf_stats
2497 		= netdev_alloc_pcpu_stats(struct netvsc_vf_pcpu_stats);
2498 	if (!net_device_ctx->vf_stats)
2499 		goto no_stats;
2500 
2501 	net->netdev_ops = &device_ops;
2502 	net->ethtool_ops = &ethtool_ops;
2503 	SET_NETDEV_DEV(net, &dev->device);
2504 
2505 	/* We always need headroom for rndis header */
2506 	net->needed_headroom = RNDIS_AND_PPI_SIZE;
2507 
2508 	/* Initialize the number of queues to be 1, we may change it if more
2509 	 * channels are offered later.
2510 	 */
2511 	netif_set_real_num_tx_queues(net, 1);
2512 	netif_set_real_num_rx_queues(net, 1);
2513 
2514 	/* Notify the netvsc driver of the new device */
2515 	device_info = netvsc_devinfo_get(NULL);
2516 
2517 	if (!device_info) {
2518 		ret = -ENOMEM;
2519 		goto devinfo_failed;
2520 	}
2521 
2522 	nvdev = rndis_filter_device_add(dev, device_info);
2523 	if (IS_ERR(nvdev)) {
2524 		ret = PTR_ERR(nvdev);
2525 		netdev_err(net, "unable to add netvsc device (ret %d)\n", ret);
2526 		goto rndis_failed;
2527 	}
2528 
2529 	memcpy(net->dev_addr, device_info->mac_adr, ETH_ALEN);
2530 
2531 	/* We must get rtnl lock before scheduling nvdev->subchan_work,
2532 	 * otherwise netvsc_subchan_work() can get rtnl lock first and wait
2533 	 * all subchannels to show up, but that may not happen because
2534 	 * netvsc_probe() can't get rtnl lock and as a result vmbus_onoffer()
2535 	 * -> ... -> device_add() -> ... -> __device_attach() can't get
2536 	 * the device lock, so all the subchannels can't be processed --
2537 	 * finally netvsc_subchan_work() hangs forever.
2538 	 */
2539 	rtnl_lock();
2540 
2541 	if (nvdev->num_chn > 1)
2542 		schedule_work(&nvdev->subchan_work);
2543 
2544 	/* hw_features computed in rndis_netdev_set_hwcaps() */
2545 	net->features = net->hw_features |
2546 		NETIF_F_HIGHDMA | NETIF_F_HW_VLAN_CTAG_TX |
2547 		NETIF_F_HW_VLAN_CTAG_RX;
2548 	net->vlan_features = net->features;
2549 
2550 	netdev_lockdep_set_classes(net);
2551 
2552 	/* MTU range: 68 - 1500 or 65521 */
2553 	net->min_mtu = NETVSC_MTU_MIN;
2554 	if (nvdev->nvsp_version >= NVSP_PROTOCOL_VERSION_2)
2555 		net->max_mtu = NETVSC_MTU - ETH_HLEN;
2556 	else
2557 		net->max_mtu = ETH_DATA_LEN;
2558 
2559 	nvdev->tx_disable = false;
2560 
2561 	ret = register_netdevice(net);
2562 	if (ret != 0) {
2563 		pr_err("Unable to register netdev.\n");
2564 		goto register_failed;
2565 	}
2566 
2567 	list_add(&net_device_ctx->list, &netvsc_dev_list);
2568 	rtnl_unlock();
2569 
2570 	netvsc_devinfo_put(device_info);
2571 	return 0;
2572 
2573 register_failed:
2574 	rtnl_unlock();
2575 	rndis_filter_device_remove(dev, nvdev);
2576 rndis_failed:
2577 	netvsc_devinfo_put(device_info);
2578 devinfo_failed:
2579 	free_percpu(net_device_ctx->vf_stats);
2580 no_stats:
2581 	hv_set_drvdata(dev, NULL);
2582 	free_netdev(net);
2583 no_net:
2584 	return ret;
2585 }
2586 
2587 static int netvsc_remove(struct hv_device *dev)
2588 {
2589 	struct net_device_context *ndev_ctx;
2590 	struct net_device *vf_netdev, *net;
2591 	struct netvsc_device *nvdev;
2592 
2593 	net = hv_get_drvdata(dev);
2594 	if (net == NULL) {
2595 		dev_err(&dev->device, "No net device to remove\n");
2596 		return 0;
2597 	}
2598 
2599 	ndev_ctx = netdev_priv(net);
2600 
2601 	cancel_delayed_work_sync(&ndev_ctx->dwork);
2602 
2603 	rtnl_lock();
2604 	nvdev = rtnl_dereference(ndev_ctx->nvdev);
2605 	if (nvdev) {
2606 		cancel_work_sync(&nvdev->subchan_work);
2607 		netvsc_xdp_set(net, NULL, NULL, nvdev);
2608 	}
2609 
2610 	/*
2611 	 * Call to the vsc driver to let it know that the device is being
2612 	 * removed. Also blocks mtu and channel changes.
2613 	 */
2614 	vf_netdev = rtnl_dereference(ndev_ctx->vf_netdev);
2615 	if (vf_netdev)
2616 		netvsc_unregister_vf(vf_netdev);
2617 
2618 	if (nvdev)
2619 		rndis_filter_device_remove(dev, nvdev);
2620 
2621 	unregister_netdevice(net);
2622 	list_del(&ndev_ctx->list);
2623 
2624 	rtnl_unlock();
2625 
2626 	hv_set_drvdata(dev, NULL);
2627 
2628 	free_percpu(ndev_ctx->vf_stats);
2629 	free_netdev(net);
2630 	return 0;
2631 }
2632 
2633 static int netvsc_suspend(struct hv_device *dev)
2634 {
2635 	struct net_device_context *ndev_ctx;
2636 	struct netvsc_device *nvdev;
2637 	struct net_device *net;
2638 	int ret;
2639 
2640 	net = hv_get_drvdata(dev);
2641 
2642 	ndev_ctx = netdev_priv(net);
2643 	cancel_delayed_work_sync(&ndev_ctx->dwork);
2644 
2645 	rtnl_lock();
2646 
2647 	nvdev = rtnl_dereference(ndev_ctx->nvdev);
2648 	if (nvdev == NULL) {
2649 		ret = -ENODEV;
2650 		goto out;
2651 	}
2652 
2653 	/* Save the current config info */
2654 	ndev_ctx->saved_netvsc_dev_info = netvsc_devinfo_get(nvdev);
2655 
2656 	ret = netvsc_detach(net, nvdev);
2657 out:
2658 	rtnl_unlock();
2659 
2660 	return ret;
2661 }
2662 
2663 static int netvsc_resume(struct hv_device *dev)
2664 {
2665 	struct net_device *net = hv_get_drvdata(dev);
2666 	struct net_device_context *net_device_ctx;
2667 	struct netvsc_device_info *device_info;
2668 	int ret;
2669 
2670 	rtnl_lock();
2671 
2672 	net_device_ctx = netdev_priv(net);
2673 
2674 	/* Reset the data path to the netvsc NIC before re-opening the vmbus
2675 	 * channel. Later netvsc_netdev_event() will switch the data path to
2676 	 * the VF upon the UP or CHANGE event.
2677 	 */
2678 	net_device_ctx->data_path_is_vf = false;
2679 	device_info = net_device_ctx->saved_netvsc_dev_info;
2680 
2681 	ret = netvsc_attach(net, device_info);
2682 
2683 	netvsc_devinfo_put(device_info);
2684 	net_device_ctx->saved_netvsc_dev_info = NULL;
2685 
2686 	rtnl_unlock();
2687 
2688 	return ret;
2689 }
2690 static const struct hv_vmbus_device_id id_table[] = {
2691 	/* Network guid */
2692 	{ HV_NIC_GUID, },
2693 	{ },
2694 };
2695 
2696 MODULE_DEVICE_TABLE(vmbus, id_table);
2697 
2698 /* The one and only one */
2699 static struct  hv_driver netvsc_drv = {
2700 	.name = KBUILD_MODNAME,
2701 	.id_table = id_table,
2702 	.probe = netvsc_probe,
2703 	.remove = netvsc_remove,
2704 	.suspend = netvsc_suspend,
2705 	.resume = netvsc_resume,
2706 	.driver = {
2707 		.probe_type = PROBE_FORCE_SYNCHRONOUS,
2708 	},
2709 };
2710 
2711 /*
2712  * On Hyper-V, every VF interface is matched with a corresponding
2713  * synthetic interface. The synthetic interface is presented first
2714  * to the guest. When the corresponding VF instance is registered,
2715  * we will take care of switching the data path.
2716  */
2717 static int netvsc_netdev_event(struct notifier_block *this,
2718 			       unsigned long event, void *ptr)
2719 {
2720 	struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
2721 
2722 	/* Skip our own events */
2723 	if (event_dev->netdev_ops == &device_ops)
2724 		return NOTIFY_DONE;
2725 
2726 	/* Avoid non-Ethernet type devices */
2727 	if (event_dev->type != ARPHRD_ETHER)
2728 		return NOTIFY_DONE;
2729 
2730 	/* Avoid Vlan dev with same MAC registering as VF */
2731 	if (is_vlan_dev(event_dev))
2732 		return NOTIFY_DONE;
2733 
2734 	/* Avoid Bonding master dev with same MAC registering as VF */
2735 	if ((event_dev->priv_flags & IFF_BONDING) &&
2736 	    (event_dev->flags & IFF_MASTER))
2737 		return NOTIFY_DONE;
2738 
2739 	switch (event) {
2740 	case NETDEV_REGISTER:
2741 		return netvsc_register_vf(event_dev);
2742 	case NETDEV_UNREGISTER:
2743 		return netvsc_unregister_vf(event_dev);
2744 	case NETDEV_UP:
2745 	case NETDEV_DOWN:
2746 	case NETDEV_CHANGE:
2747 	case NETDEV_GOING_DOWN:
2748 		return netvsc_vf_changed(event_dev, event);
2749 	default:
2750 		return NOTIFY_DONE;
2751 	}
2752 }
2753 
2754 static struct notifier_block netvsc_netdev_notifier = {
2755 	.notifier_call = netvsc_netdev_event,
2756 };
2757 
2758 static void __exit netvsc_drv_exit(void)
2759 {
2760 	unregister_netdevice_notifier(&netvsc_netdev_notifier);
2761 	vmbus_driver_unregister(&netvsc_drv);
2762 }
2763 
2764 static int __init netvsc_drv_init(void)
2765 {
2766 	int ret;
2767 
2768 	if (ring_size < RING_SIZE_MIN) {
2769 		ring_size = RING_SIZE_MIN;
2770 		pr_info("Increased ring_size to %u (min allowed)\n",
2771 			ring_size);
2772 	}
2773 	netvsc_ring_bytes = ring_size * PAGE_SIZE;
2774 
2775 	ret = vmbus_driver_register(&netvsc_drv);
2776 	if (ret)
2777 		return ret;
2778 
2779 	register_netdevice_notifier(&netvsc_netdev_notifier);
2780 	return 0;
2781 }
2782 
2783 MODULE_LICENSE("GPL");
2784 MODULE_DESCRIPTION("Microsoft Hyper-V network driver");
2785 
2786 module_init(netvsc_drv_init);
2787 module_exit(netvsc_drv_exit);
2788