xref: /linux/drivers/net/hyperv/netvsc_drv.c (revision 4b132aacb0768ac1e652cf517097ea6f237214b9)
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 
42 #define LINKCHANGE_INT (2 * HZ)
43 #define VF_TAKEOVER_INT (HZ / 10)
44 
45 /* Macros to define the context of vf registration */
46 #define VF_REG_IN_PROBE		1
47 #define VF_REG_IN_NOTIFIER	2
48 
49 static unsigned int ring_size __ro_after_init = 128;
50 module_param(ring_size, uint, 0444);
51 MODULE_PARM_DESC(ring_size, "Ring buffer size (# of 4K pages)");
52 unsigned int netvsc_ring_bytes __ro_after_init;
53 
54 static const u32 default_msg = NETIF_MSG_DRV | NETIF_MSG_PROBE |
55 				NETIF_MSG_LINK | NETIF_MSG_IFUP |
56 				NETIF_MSG_IFDOWN | NETIF_MSG_RX_ERR |
57 				NETIF_MSG_TX_ERR;
58 
59 static int debug = -1;
60 module_param(debug, int, 0444);
61 MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
62 
63 static LIST_HEAD(netvsc_dev_list);
64 
65 static void netvsc_change_rx_flags(struct net_device *net, int change)
66 {
67 	struct net_device_context *ndev_ctx = netdev_priv(net);
68 	struct net_device *vf_netdev = rtnl_dereference(ndev_ctx->vf_netdev);
69 	int inc;
70 
71 	if (!vf_netdev)
72 		return;
73 
74 	if (change & IFF_PROMISC) {
75 		inc = (net->flags & IFF_PROMISC) ? 1 : -1;
76 		dev_set_promiscuity(vf_netdev, inc);
77 	}
78 
79 	if (change & IFF_ALLMULTI) {
80 		inc = (net->flags & IFF_ALLMULTI) ? 1 : -1;
81 		dev_set_allmulti(vf_netdev, inc);
82 	}
83 }
84 
85 static void netvsc_set_rx_mode(struct net_device *net)
86 {
87 	struct net_device_context *ndev_ctx = netdev_priv(net);
88 	struct net_device *vf_netdev;
89 	struct netvsc_device *nvdev;
90 
91 	rcu_read_lock();
92 	vf_netdev = rcu_dereference(ndev_ctx->vf_netdev);
93 	if (vf_netdev) {
94 		dev_uc_sync(vf_netdev, net);
95 		dev_mc_sync(vf_netdev, net);
96 	}
97 
98 	nvdev = rcu_dereference(ndev_ctx->nvdev);
99 	if (nvdev)
100 		rndis_filter_update(nvdev);
101 	rcu_read_unlock();
102 }
103 
104 static void netvsc_tx_enable(struct netvsc_device *nvscdev,
105 			     struct net_device *ndev)
106 {
107 	nvscdev->tx_disable = false;
108 	virt_wmb(); /* ensure queue wake up mechanism is on */
109 
110 	netif_tx_wake_all_queues(ndev);
111 }
112 
113 static int netvsc_open(struct net_device *net)
114 {
115 	struct net_device_context *ndev_ctx = netdev_priv(net);
116 	struct net_device *vf_netdev = rtnl_dereference(ndev_ctx->vf_netdev);
117 	struct netvsc_device *nvdev = rtnl_dereference(ndev_ctx->nvdev);
118 	struct rndis_device *rdev;
119 	int ret = 0;
120 
121 	netif_carrier_off(net);
122 
123 	/* Open up the device */
124 	ret = rndis_filter_open(nvdev);
125 	if (ret != 0) {
126 		netdev_err(net, "unable to open device (ret %d).\n", ret);
127 		return ret;
128 	}
129 
130 	rdev = nvdev->extension;
131 	if (!rdev->link_state) {
132 		netif_carrier_on(net);
133 		netvsc_tx_enable(nvdev, net);
134 	}
135 
136 	if (vf_netdev) {
137 		/* Setting synthetic device up transparently sets
138 		 * slave as up. If open fails, then slave will be
139 		 * still be offline (and not used).
140 		 */
141 		ret = dev_open(vf_netdev, NULL);
142 		if (ret)
143 			netdev_warn(net,
144 				    "unable to open slave: %s: %d\n",
145 				    vf_netdev->name, ret);
146 	}
147 	return 0;
148 }
149 
150 static int netvsc_wait_until_empty(struct netvsc_device *nvdev)
151 {
152 	unsigned int retry = 0;
153 	int i;
154 
155 	/* Ensure pending bytes in ring are read */
156 	for (;;) {
157 		u32 aread = 0;
158 
159 		for (i = 0; i < nvdev->num_chn; i++) {
160 			struct vmbus_channel *chn
161 				= nvdev->chan_table[i].channel;
162 
163 			if (!chn)
164 				continue;
165 
166 			/* make sure receive not running now */
167 			napi_synchronize(&nvdev->chan_table[i].napi);
168 
169 			aread = hv_get_bytes_to_read(&chn->inbound);
170 			if (aread)
171 				break;
172 
173 			aread = hv_get_bytes_to_read(&chn->outbound);
174 			if (aread)
175 				break;
176 		}
177 
178 		if (aread == 0)
179 			return 0;
180 
181 		if (++retry > RETRY_MAX)
182 			return -ETIMEDOUT;
183 
184 		usleep_range(RETRY_US_LO, RETRY_US_HI);
185 	}
186 }
187 
188 static void netvsc_tx_disable(struct netvsc_device *nvscdev,
189 			      struct net_device *ndev)
190 {
191 	if (nvscdev) {
192 		nvscdev->tx_disable = true;
193 		virt_wmb(); /* ensure txq will not wake up after stop */
194 	}
195 
196 	netif_tx_disable(ndev);
197 }
198 
199 static int netvsc_close(struct net_device *net)
200 {
201 	struct net_device_context *net_device_ctx = netdev_priv(net);
202 	struct net_device *vf_netdev
203 		= rtnl_dereference(net_device_ctx->vf_netdev);
204 	struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
205 	int ret;
206 
207 	netvsc_tx_disable(nvdev, net);
208 
209 	/* No need to close rndis filter if it is removed already */
210 	if (!nvdev)
211 		return 0;
212 
213 	ret = rndis_filter_close(nvdev);
214 	if (ret != 0) {
215 		netdev_err(net, "unable to close device (ret %d).\n", ret);
216 		return ret;
217 	}
218 
219 	ret = netvsc_wait_until_empty(nvdev);
220 	if (ret)
221 		netdev_err(net, "Ring buffer not empty after closing rndis\n");
222 
223 	if (vf_netdev)
224 		dev_close(vf_netdev);
225 
226 	return ret;
227 }
228 
229 static inline void *init_ppi_data(struct rndis_message *msg,
230 				  u32 ppi_size, u32 pkt_type)
231 {
232 	struct rndis_packet *rndis_pkt = &msg->msg.pkt;
233 	struct rndis_per_packet_info *ppi;
234 
235 	rndis_pkt->data_offset += ppi_size;
236 	ppi = (void *)rndis_pkt + rndis_pkt->per_pkt_info_offset
237 		+ rndis_pkt->per_pkt_info_len;
238 
239 	ppi->size = ppi_size;
240 	ppi->type = pkt_type;
241 	ppi->internal = 0;
242 	ppi->ppi_offset = sizeof(struct rndis_per_packet_info);
243 
244 	rndis_pkt->per_pkt_info_len += ppi_size;
245 
246 	return ppi + 1;
247 }
248 
249 static inline int netvsc_get_tx_queue(struct net_device *ndev,
250 				      struct sk_buff *skb, int old_idx)
251 {
252 	const struct net_device_context *ndc = netdev_priv(ndev);
253 	struct sock *sk = skb->sk;
254 	int q_idx;
255 
256 	q_idx = ndc->tx_table[netvsc_get_hash(skb, ndc) &
257 			      (VRSS_SEND_TAB_SIZE - 1)];
258 
259 	/* If queue index changed record the new value */
260 	if (q_idx != old_idx &&
261 	    sk && sk_fullsock(sk) && rcu_access_pointer(sk->sk_dst_cache))
262 		sk_tx_queue_set(sk, q_idx);
263 
264 	return q_idx;
265 }
266 
267 /*
268  * Select queue for transmit.
269  *
270  * If a valid queue has already been assigned, then use that.
271  * Otherwise compute tx queue based on hash and the send table.
272  *
273  * This is basically similar to default (netdev_pick_tx) with the added step
274  * of using the host send_table when no other queue has been assigned.
275  *
276  * TODO support XPS - but get_xps_queue not exported
277  */
278 static u16 netvsc_pick_tx(struct net_device *ndev, struct sk_buff *skb)
279 {
280 	int q_idx = sk_tx_queue_get(skb->sk);
281 
282 	if (q_idx < 0 || skb->ooo_okay || q_idx >= ndev->real_num_tx_queues) {
283 		/* If forwarding a packet, we use the recorded queue when
284 		 * available for better cache locality.
285 		 */
286 		if (skb_rx_queue_recorded(skb))
287 			q_idx = skb_get_rx_queue(skb);
288 		else
289 			q_idx = netvsc_get_tx_queue(ndev, skb, q_idx);
290 	}
291 
292 	return q_idx;
293 }
294 
295 static u16 netvsc_select_queue(struct net_device *ndev, struct sk_buff *skb,
296 			       struct net_device *sb_dev)
297 {
298 	struct net_device_context *ndc = netdev_priv(ndev);
299 	struct net_device *vf_netdev;
300 	u16 txq;
301 
302 	rcu_read_lock();
303 	vf_netdev = rcu_dereference(ndc->vf_netdev);
304 	if (vf_netdev) {
305 		const struct net_device_ops *vf_ops = vf_netdev->netdev_ops;
306 
307 		if (vf_ops->ndo_select_queue)
308 			txq = vf_ops->ndo_select_queue(vf_netdev, skb, sb_dev);
309 		else
310 			txq = netdev_pick_tx(vf_netdev, skb, NULL);
311 
312 		/* Record the queue selected by VF so that it can be
313 		 * used for common case where VF has more queues than
314 		 * the synthetic device.
315 		 */
316 		qdisc_skb_cb(skb)->slave_dev_queue_mapping = txq;
317 	} else {
318 		txq = netvsc_pick_tx(ndev, skb);
319 	}
320 	rcu_read_unlock();
321 
322 	while (txq >= ndev->real_num_tx_queues)
323 		txq -= ndev->real_num_tx_queues;
324 
325 	return txq;
326 }
327 
328 static u32 fill_pg_buf(unsigned long hvpfn, u32 offset, u32 len,
329 		       struct hv_page_buffer *pb)
330 {
331 	int j = 0;
332 
333 	hvpfn += offset >> HV_HYP_PAGE_SHIFT;
334 	offset = offset & ~HV_HYP_PAGE_MASK;
335 
336 	while (len > 0) {
337 		unsigned long bytes;
338 
339 		bytes = HV_HYP_PAGE_SIZE - offset;
340 		if (bytes > len)
341 			bytes = len;
342 		pb[j].pfn = hvpfn;
343 		pb[j].offset = offset;
344 		pb[j].len = bytes;
345 
346 		offset += bytes;
347 		len -= bytes;
348 
349 		if (offset == HV_HYP_PAGE_SIZE && len) {
350 			hvpfn++;
351 			offset = 0;
352 			j++;
353 		}
354 	}
355 
356 	return j + 1;
357 }
358 
359 static u32 init_page_array(void *hdr, u32 len, struct sk_buff *skb,
360 			   struct hv_netvsc_packet *packet,
361 			   struct hv_page_buffer *pb)
362 {
363 	u32 slots_used = 0;
364 	char *data = skb->data;
365 	int frags = skb_shinfo(skb)->nr_frags;
366 	int i;
367 
368 	/* The packet is laid out thus:
369 	 * 1. hdr: RNDIS header and PPI
370 	 * 2. skb linear data
371 	 * 3. skb fragment data
372 	 */
373 	slots_used += fill_pg_buf(virt_to_hvpfn(hdr),
374 				  offset_in_hvpage(hdr),
375 				  len,
376 				  &pb[slots_used]);
377 
378 	packet->rmsg_size = len;
379 	packet->rmsg_pgcnt = slots_used;
380 
381 	slots_used += fill_pg_buf(virt_to_hvpfn(data),
382 				  offset_in_hvpage(data),
383 				  skb_headlen(skb),
384 				  &pb[slots_used]);
385 
386 	for (i = 0; i < frags; i++) {
387 		skb_frag_t *frag = skb_shinfo(skb)->frags + i;
388 
389 		slots_used += fill_pg_buf(page_to_hvpfn(skb_frag_page(frag)),
390 					  skb_frag_off(frag),
391 					  skb_frag_size(frag),
392 					  &pb[slots_used]);
393 	}
394 	return slots_used;
395 }
396 
397 static int count_skb_frag_slots(struct sk_buff *skb)
398 {
399 	int i, frags = skb_shinfo(skb)->nr_frags;
400 	int pages = 0;
401 
402 	for (i = 0; i < frags; i++) {
403 		skb_frag_t *frag = skb_shinfo(skb)->frags + i;
404 		unsigned long size = skb_frag_size(frag);
405 		unsigned long offset = skb_frag_off(frag);
406 
407 		/* Skip unused frames from start of page */
408 		offset &= ~HV_HYP_PAGE_MASK;
409 		pages += HVPFN_UP(offset + size);
410 	}
411 	return pages;
412 }
413 
414 static int netvsc_get_slots(struct sk_buff *skb)
415 {
416 	char *data = skb->data;
417 	unsigned int offset = offset_in_hvpage(data);
418 	unsigned int len = skb_headlen(skb);
419 	int slots;
420 	int frag_slots;
421 
422 	slots = DIV_ROUND_UP(offset + len, HV_HYP_PAGE_SIZE);
423 	frag_slots = count_skb_frag_slots(skb);
424 	return slots + frag_slots;
425 }
426 
427 static u32 net_checksum_info(struct sk_buff *skb)
428 {
429 	if (skb->protocol == htons(ETH_P_IP)) {
430 		struct iphdr *ip = ip_hdr(skb);
431 
432 		if (ip->protocol == IPPROTO_TCP)
433 			return TRANSPORT_INFO_IPV4_TCP;
434 		else if (ip->protocol == IPPROTO_UDP)
435 			return TRANSPORT_INFO_IPV4_UDP;
436 	} else {
437 		struct ipv6hdr *ip6 = ipv6_hdr(skb);
438 
439 		if (ip6->nexthdr == IPPROTO_TCP)
440 			return TRANSPORT_INFO_IPV6_TCP;
441 		else if (ip6->nexthdr == IPPROTO_UDP)
442 			return TRANSPORT_INFO_IPV6_UDP;
443 	}
444 
445 	return TRANSPORT_INFO_NOT_IP;
446 }
447 
448 /* Send skb on the slave VF device. */
449 static int netvsc_vf_xmit(struct net_device *net, struct net_device *vf_netdev,
450 			  struct sk_buff *skb)
451 {
452 	struct net_device_context *ndev_ctx = netdev_priv(net);
453 	unsigned int len = skb->len;
454 	int rc;
455 
456 	skb->dev = vf_netdev;
457 	skb_record_rx_queue(skb, qdisc_skb_cb(skb)->slave_dev_queue_mapping);
458 
459 	rc = dev_queue_xmit(skb);
460 	if (likely(rc == NET_XMIT_SUCCESS || rc == NET_XMIT_CN)) {
461 		struct netvsc_vf_pcpu_stats *pcpu_stats
462 			= this_cpu_ptr(ndev_ctx->vf_stats);
463 
464 		u64_stats_update_begin(&pcpu_stats->syncp);
465 		pcpu_stats->tx_packets++;
466 		pcpu_stats->tx_bytes += len;
467 		u64_stats_update_end(&pcpu_stats->syncp);
468 	} else {
469 		this_cpu_inc(ndev_ctx->vf_stats->tx_dropped);
470 	}
471 
472 	return rc;
473 }
474 
475 static int netvsc_xmit(struct sk_buff *skb, struct net_device *net, bool xdp_tx)
476 {
477 	struct net_device_context *net_device_ctx = netdev_priv(net);
478 	struct hv_netvsc_packet *packet = NULL;
479 	int ret;
480 	unsigned int num_data_pgs;
481 	struct rndis_message *rndis_msg;
482 	struct net_device *vf_netdev;
483 	u32 rndis_msg_size;
484 	u32 hash;
485 	struct hv_page_buffer pb[MAX_PAGE_BUFFER_COUNT];
486 
487 	/* If VF is present and up then redirect packets to it.
488 	 * Skip the VF if it is marked down or has no carrier.
489 	 * If netpoll is in uses, then VF can not be used either.
490 	 */
491 	vf_netdev = rcu_dereference_bh(net_device_ctx->vf_netdev);
492 	if (vf_netdev && netif_running(vf_netdev) &&
493 	    netif_carrier_ok(vf_netdev) && !netpoll_tx_running(net) &&
494 	    net_device_ctx->data_path_is_vf)
495 		return netvsc_vf_xmit(net, vf_netdev, skb);
496 
497 	/* We will atmost need two pages to describe the rndis
498 	 * header. We can only transmit MAX_PAGE_BUFFER_COUNT number
499 	 * of pages in a single packet. If skb is scattered around
500 	 * more pages we try linearizing it.
501 	 */
502 
503 	num_data_pgs = netvsc_get_slots(skb) + 2;
504 
505 	if (unlikely(num_data_pgs > MAX_PAGE_BUFFER_COUNT)) {
506 		++net_device_ctx->eth_stats.tx_scattered;
507 
508 		if (skb_linearize(skb))
509 			goto no_memory;
510 
511 		num_data_pgs = netvsc_get_slots(skb) + 2;
512 		if (num_data_pgs > MAX_PAGE_BUFFER_COUNT) {
513 			++net_device_ctx->eth_stats.tx_too_big;
514 			goto drop;
515 		}
516 	}
517 
518 	/*
519 	 * Place the rndis header in the skb head room and
520 	 * the skb->cb will be used for hv_netvsc_packet
521 	 * structure.
522 	 */
523 	ret = skb_cow_head(skb, RNDIS_AND_PPI_SIZE);
524 	if (ret)
525 		goto no_memory;
526 
527 	/* Use the skb control buffer for building up the packet */
528 	BUILD_BUG_ON(sizeof(struct hv_netvsc_packet) >
529 			sizeof_field(struct sk_buff, cb));
530 	packet = (struct hv_netvsc_packet *)skb->cb;
531 
532 	packet->q_idx = skb_get_queue_mapping(skb);
533 
534 	packet->total_data_buflen = skb->len;
535 	packet->total_bytes = skb->len;
536 	packet->total_packets = 1;
537 
538 	rndis_msg = (struct rndis_message *)skb->head;
539 
540 	/* Add the rndis header */
541 	rndis_msg->ndis_msg_type = RNDIS_MSG_PACKET;
542 	rndis_msg->msg_len = packet->total_data_buflen;
543 
544 	rndis_msg->msg.pkt = (struct rndis_packet) {
545 		.data_offset = sizeof(struct rndis_packet),
546 		.data_len = packet->total_data_buflen,
547 		.per_pkt_info_offset = sizeof(struct rndis_packet),
548 	};
549 
550 	rndis_msg_size = RNDIS_MESSAGE_SIZE(struct rndis_packet);
551 
552 	hash = skb_get_hash_raw(skb);
553 	if (hash != 0 && net->real_num_tx_queues > 1) {
554 		u32 *hash_info;
555 
556 		rndis_msg_size += NDIS_HASH_PPI_SIZE;
557 		hash_info = init_ppi_data(rndis_msg, NDIS_HASH_PPI_SIZE,
558 					  NBL_HASH_VALUE);
559 		*hash_info = hash;
560 	}
561 
562 	/* When using AF_PACKET we need to drop VLAN header from
563 	 * the frame and update the SKB to allow the HOST OS
564 	 * to transmit the 802.1Q packet
565 	 */
566 	if (skb->protocol == htons(ETH_P_8021Q)) {
567 		u16 vlan_tci;
568 
569 		skb_reset_mac_header(skb);
570 		if (eth_type_vlan(eth_hdr(skb)->h_proto)) {
571 			if (unlikely(__skb_vlan_pop(skb, &vlan_tci) != 0)) {
572 				++net_device_ctx->eth_stats.vlan_error;
573 				goto drop;
574 			}
575 
576 			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tci);
577 			/* Update the NDIS header pkt lengths */
578 			packet->total_data_buflen -= VLAN_HLEN;
579 			packet->total_bytes -= VLAN_HLEN;
580 			rndis_msg->msg_len = packet->total_data_buflen;
581 			rndis_msg->msg.pkt.data_len = packet->total_data_buflen;
582 		}
583 	}
584 
585 	if (skb_vlan_tag_present(skb)) {
586 		struct ndis_pkt_8021q_info *vlan;
587 
588 		rndis_msg_size += NDIS_VLAN_PPI_SIZE;
589 		vlan = init_ppi_data(rndis_msg, NDIS_VLAN_PPI_SIZE,
590 				     IEEE_8021Q_INFO);
591 
592 		vlan->value = 0;
593 		vlan->vlanid = skb_vlan_tag_get_id(skb);
594 		vlan->cfi = skb_vlan_tag_get_cfi(skb);
595 		vlan->pri = skb_vlan_tag_get_prio(skb);
596 	}
597 
598 	if (skb_is_gso(skb)) {
599 		struct ndis_tcp_lso_info *lso_info;
600 
601 		rndis_msg_size += NDIS_LSO_PPI_SIZE;
602 		lso_info = init_ppi_data(rndis_msg, NDIS_LSO_PPI_SIZE,
603 					 TCP_LARGESEND_PKTINFO);
604 
605 		lso_info->value = 0;
606 		lso_info->lso_v2_transmit.type = NDIS_TCP_LARGE_SEND_OFFLOAD_V2_TYPE;
607 		if (skb->protocol == htons(ETH_P_IP)) {
608 			lso_info->lso_v2_transmit.ip_version =
609 				NDIS_TCP_LARGE_SEND_OFFLOAD_IPV4;
610 			ip_hdr(skb)->tot_len = 0;
611 			ip_hdr(skb)->check = 0;
612 			tcp_hdr(skb)->check =
613 				~csum_tcpudp_magic(ip_hdr(skb)->saddr,
614 						   ip_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
615 		} else {
616 			lso_info->lso_v2_transmit.ip_version =
617 				NDIS_TCP_LARGE_SEND_OFFLOAD_IPV6;
618 			tcp_v6_gso_csum_prep(skb);
619 		}
620 		lso_info->lso_v2_transmit.tcp_header_offset = skb_transport_offset(skb);
621 		lso_info->lso_v2_transmit.mss = skb_shinfo(skb)->gso_size;
622 	} else if (skb->ip_summed == CHECKSUM_PARTIAL) {
623 		if (net_checksum_info(skb) & net_device_ctx->tx_checksum_mask) {
624 			struct ndis_tcp_ip_checksum_info *csum_info;
625 
626 			rndis_msg_size += NDIS_CSUM_PPI_SIZE;
627 			csum_info = init_ppi_data(rndis_msg, NDIS_CSUM_PPI_SIZE,
628 						  TCPIP_CHKSUM_PKTINFO);
629 
630 			csum_info->value = 0;
631 			csum_info->transmit.tcp_header_offset = skb_transport_offset(skb);
632 
633 			if (skb->protocol == htons(ETH_P_IP)) {
634 				csum_info->transmit.is_ipv4 = 1;
635 
636 				if (ip_hdr(skb)->protocol == IPPROTO_TCP)
637 					csum_info->transmit.tcp_checksum = 1;
638 				else
639 					csum_info->transmit.udp_checksum = 1;
640 			} else {
641 				csum_info->transmit.is_ipv6 = 1;
642 
643 				if (ipv6_hdr(skb)->nexthdr == IPPROTO_TCP)
644 					csum_info->transmit.tcp_checksum = 1;
645 				else
646 					csum_info->transmit.udp_checksum = 1;
647 			}
648 		} else {
649 			/* Can't do offload of this type of checksum */
650 			if (skb_checksum_help(skb))
651 				goto drop;
652 		}
653 	}
654 
655 	/* Start filling in the page buffers with the rndis hdr */
656 	rndis_msg->msg_len += rndis_msg_size;
657 	packet->total_data_buflen = rndis_msg->msg_len;
658 	packet->page_buf_cnt = init_page_array(rndis_msg, rndis_msg_size,
659 					       skb, packet, pb);
660 
661 	/* timestamp packet in software */
662 	skb_tx_timestamp(skb);
663 
664 	ret = netvsc_send(net, packet, rndis_msg, pb, skb, xdp_tx);
665 	if (likely(ret == 0))
666 		return NETDEV_TX_OK;
667 
668 	if (ret == -EAGAIN) {
669 		++net_device_ctx->eth_stats.tx_busy;
670 		return NETDEV_TX_BUSY;
671 	}
672 
673 	if (ret == -ENOSPC)
674 		++net_device_ctx->eth_stats.tx_no_space;
675 
676 drop:
677 	dev_kfree_skb_any(skb);
678 	net->stats.tx_dropped++;
679 
680 	return NETDEV_TX_OK;
681 
682 no_memory:
683 	++net_device_ctx->eth_stats.tx_no_memory;
684 	goto drop;
685 }
686 
687 static netdev_tx_t netvsc_start_xmit(struct sk_buff *skb,
688 				     struct net_device *ndev)
689 {
690 	return netvsc_xmit(skb, ndev, false);
691 }
692 
693 /*
694  * netvsc_linkstatus_callback - Link up/down notification
695  */
696 void netvsc_linkstatus_callback(struct net_device *net,
697 				struct rndis_message *resp,
698 				void *data, u32 data_buflen)
699 {
700 	struct rndis_indicate_status *indicate = &resp->msg.indicate_status;
701 	struct net_device_context *ndev_ctx = netdev_priv(net);
702 	struct netvsc_reconfig *event;
703 	unsigned long flags;
704 
705 	/* Ensure the packet is big enough to access its fields */
706 	if (resp->msg_len - RNDIS_HEADER_SIZE < sizeof(struct rndis_indicate_status)) {
707 		netdev_err(net, "invalid rndis_indicate_status packet, len: %u\n",
708 			   resp->msg_len);
709 		return;
710 	}
711 
712 	/* Copy the RNDIS indicate status into nvchan->recv_buf */
713 	memcpy(indicate, data + RNDIS_HEADER_SIZE, sizeof(*indicate));
714 
715 	/* Update the physical link speed when changing to another vSwitch */
716 	if (indicate->status == RNDIS_STATUS_LINK_SPEED_CHANGE) {
717 		u32 speed;
718 
719 		/* Validate status_buf_offset and status_buflen.
720 		 *
721 		 * Certain (pre-Fe) implementations of Hyper-V's vSwitch didn't account
722 		 * for the status buffer field in resp->msg_len; perform the validation
723 		 * using data_buflen (>= resp->msg_len).
724 		 */
725 		if (indicate->status_buflen < sizeof(speed) ||
726 		    indicate->status_buf_offset < sizeof(*indicate) ||
727 		    data_buflen - RNDIS_HEADER_SIZE < indicate->status_buf_offset ||
728 		    data_buflen - RNDIS_HEADER_SIZE - indicate->status_buf_offset
729 				< indicate->status_buflen) {
730 			netdev_err(net, "invalid rndis_indicate_status packet\n");
731 			return;
732 		}
733 
734 		speed = *(u32 *)(data + RNDIS_HEADER_SIZE + indicate->status_buf_offset) / 10000;
735 		ndev_ctx->speed = speed;
736 		return;
737 	}
738 
739 	/* Handle these link change statuses below */
740 	if (indicate->status != RNDIS_STATUS_NETWORK_CHANGE &&
741 	    indicate->status != RNDIS_STATUS_MEDIA_CONNECT &&
742 	    indicate->status != RNDIS_STATUS_MEDIA_DISCONNECT)
743 		return;
744 
745 	if (net->reg_state != NETREG_REGISTERED)
746 		return;
747 
748 	event = kzalloc(sizeof(*event), GFP_ATOMIC);
749 	if (!event)
750 		return;
751 	event->event = indicate->status;
752 
753 	spin_lock_irqsave(&ndev_ctx->lock, flags);
754 	list_add_tail(&event->list, &ndev_ctx->reconfig_events);
755 	spin_unlock_irqrestore(&ndev_ctx->lock, flags);
756 
757 	schedule_delayed_work(&ndev_ctx->dwork, 0);
758 }
759 
760 /* This function should only be called after skb_record_rx_queue() */
761 void netvsc_xdp_xmit(struct sk_buff *skb, struct net_device *ndev)
762 {
763 	int rc;
764 
765 	skb->queue_mapping = skb_get_rx_queue(skb);
766 	__skb_push(skb, ETH_HLEN);
767 
768 	rc = netvsc_xmit(skb, ndev, true);
769 
770 	if (dev_xmit_complete(rc))
771 		return;
772 
773 	dev_kfree_skb_any(skb);
774 	ndev->stats.tx_dropped++;
775 }
776 
777 static void netvsc_comp_ipcsum(struct sk_buff *skb)
778 {
779 	struct iphdr *iph = (struct iphdr *)skb->data;
780 
781 	iph->check = 0;
782 	iph->check = ip_fast_csum(iph, iph->ihl);
783 }
784 
785 static struct sk_buff *netvsc_alloc_recv_skb(struct net_device *net,
786 					     struct netvsc_channel *nvchan,
787 					     struct xdp_buff *xdp)
788 {
789 	struct napi_struct *napi = &nvchan->napi;
790 	const struct ndis_pkt_8021q_info *vlan = &nvchan->rsc.vlan;
791 	const struct ndis_tcp_ip_checksum_info *csum_info =
792 						&nvchan->rsc.csum_info;
793 	const u32 *hash_info = &nvchan->rsc.hash_info;
794 	u8 ppi_flags = nvchan->rsc.ppi_flags;
795 	struct sk_buff *skb;
796 	void *xbuf = xdp->data_hard_start;
797 	int i;
798 
799 	if (xbuf) {
800 		unsigned int hdroom = xdp->data - xdp->data_hard_start;
801 		unsigned int xlen = xdp->data_end - xdp->data;
802 		unsigned int frag_size = xdp->frame_sz;
803 
804 		skb = build_skb(xbuf, frag_size);
805 
806 		if (!skb) {
807 			__free_page(virt_to_page(xbuf));
808 			return NULL;
809 		}
810 
811 		skb_reserve(skb, hdroom);
812 		skb_put(skb, xlen);
813 		skb->dev = napi->dev;
814 	} else {
815 		skb = napi_alloc_skb(napi, nvchan->rsc.pktlen);
816 
817 		if (!skb)
818 			return NULL;
819 
820 		/* Copy to skb. This copy is needed here since the memory
821 		 * pointed by hv_netvsc_packet cannot be deallocated.
822 		 */
823 		for (i = 0; i < nvchan->rsc.cnt; i++)
824 			skb_put_data(skb, nvchan->rsc.data[i],
825 				     nvchan->rsc.len[i]);
826 	}
827 
828 	skb->protocol = eth_type_trans(skb, net);
829 
830 	/* skb is already created with CHECKSUM_NONE */
831 	skb_checksum_none_assert(skb);
832 
833 	/* Incoming packets may have IP header checksum verified by the host.
834 	 * They may not have IP header checksum computed after coalescing.
835 	 * We compute it here if the flags are set, because on Linux, the IP
836 	 * checksum is always checked.
837 	 */
838 	if ((ppi_flags & NVSC_RSC_CSUM_INFO) && csum_info->receive.ip_checksum_value_invalid &&
839 	    csum_info->receive.ip_checksum_succeeded &&
840 	    skb->protocol == htons(ETH_P_IP)) {
841 		/* Check that there is enough space to hold the IP header. */
842 		if (skb_headlen(skb) < sizeof(struct iphdr)) {
843 			kfree_skb(skb);
844 			return NULL;
845 		}
846 		netvsc_comp_ipcsum(skb);
847 	}
848 
849 	/* Do L4 checksum offload if enabled and present. */
850 	if ((ppi_flags & NVSC_RSC_CSUM_INFO) && (net->features & NETIF_F_RXCSUM)) {
851 		if (csum_info->receive.tcp_checksum_succeeded ||
852 		    csum_info->receive.udp_checksum_succeeded)
853 			skb->ip_summed = CHECKSUM_UNNECESSARY;
854 	}
855 
856 	if ((ppi_flags & NVSC_RSC_HASH_INFO) && (net->features & NETIF_F_RXHASH))
857 		skb_set_hash(skb, *hash_info, PKT_HASH_TYPE_L4);
858 
859 	if (ppi_flags & NVSC_RSC_VLAN) {
860 		u16 vlan_tci = vlan->vlanid | (vlan->pri << VLAN_PRIO_SHIFT) |
861 			(vlan->cfi ? VLAN_CFI_MASK : 0);
862 
863 		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
864 				       vlan_tci);
865 	}
866 
867 	return skb;
868 }
869 
870 /*
871  * netvsc_recv_callback -  Callback when we receive a packet from the
872  * "wire" on the specified device.
873  */
874 int netvsc_recv_callback(struct net_device *net,
875 			 struct netvsc_device *net_device,
876 			 struct netvsc_channel *nvchan)
877 {
878 	struct net_device_context *net_device_ctx = netdev_priv(net);
879 	struct vmbus_channel *channel = nvchan->channel;
880 	u16 q_idx = channel->offermsg.offer.sub_channel_index;
881 	struct sk_buff *skb;
882 	struct netvsc_stats_rx *rx_stats = &nvchan->rx_stats;
883 	struct xdp_buff xdp;
884 	u32 act;
885 
886 	if (net->reg_state != NETREG_REGISTERED)
887 		return NVSP_STAT_FAIL;
888 
889 	act = netvsc_run_xdp(net, nvchan, &xdp);
890 
891 	if (act == XDP_REDIRECT)
892 		return NVSP_STAT_SUCCESS;
893 
894 	if (act != XDP_PASS && act != XDP_TX) {
895 		u64_stats_update_begin(&rx_stats->syncp);
896 		rx_stats->xdp_drop++;
897 		u64_stats_update_end(&rx_stats->syncp);
898 
899 		return NVSP_STAT_SUCCESS; /* consumed by XDP */
900 	}
901 
902 	/* Allocate a skb - TODO direct I/O to pages? */
903 	skb = netvsc_alloc_recv_skb(net, nvchan, &xdp);
904 
905 	if (unlikely(!skb)) {
906 		++net_device_ctx->eth_stats.rx_no_memory;
907 		return NVSP_STAT_FAIL;
908 	}
909 
910 	skb_record_rx_queue(skb, q_idx);
911 
912 	/*
913 	 * Even if injecting the packet, record the statistics
914 	 * on the synthetic device because modifying the VF device
915 	 * statistics will not work correctly.
916 	 */
917 	u64_stats_update_begin(&rx_stats->syncp);
918 	if (act == XDP_TX)
919 		rx_stats->xdp_tx++;
920 
921 	rx_stats->packets++;
922 	rx_stats->bytes += nvchan->rsc.pktlen;
923 
924 	if (skb->pkt_type == PACKET_BROADCAST)
925 		++rx_stats->broadcast;
926 	else if (skb->pkt_type == PACKET_MULTICAST)
927 		++rx_stats->multicast;
928 	u64_stats_update_end(&rx_stats->syncp);
929 
930 	if (act == XDP_TX) {
931 		netvsc_xdp_xmit(skb, net);
932 		return NVSP_STAT_SUCCESS;
933 	}
934 
935 	napi_gro_receive(&nvchan->napi, skb);
936 	return NVSP_STAT_SUCCESS;
937 }
938 
939 static void netvsc_get_drvinfo(struct net_device *net,
940 			       struct ethtool_drvinfo *info)
941 {
942 	strscpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
943 	strscpy(info->fw_version, "N/A", sizeof(info->fw_version));
944 }
945 
946 static void netvsc_get_channels(struct net_device *net,
947 				struct ethtool_channels *channel)
948 {
949 	struct net_device_context *net_device_ctx = netdev_priv(net);
950 	struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
951 
952 	if (nvdev) {
953 		channel->max_combined	= nvdev->max_chn;
954 		channel->combined_count = nvdev->num_chn;
955 	}
956 }
957 
958 /* Alloc struct netvsc_device_info, and initialize it from either existing
959  * struct netvsc_device, or from default values.
960  */
961 static
962 struct netvsc_device_info *netvsc_devinfo_get(struct netvsc_device *nvdev)
963 {
964 	struct netvsc_device_info *dev_info;
965 	struct bpf_prog *prog;
966 
967 	dev_info = kzalloc(sizeof(*dev_info), GFP_ATOMIC);
968 
969 	if (!dev_info)
970 		return NULL;
971 
972 	if (nvdev) {
973 		ASSERT_RTNL();
974 
975 		dev_info->num_chn = nvdev->num_chn;
976 		dev_info->send_sections = nvdev->send_section_cnt;
977 		dev_info->send_section_size = nvdev->send_section_size;
978 		dev_info->recv_sections = nvdev->recv_section_cnt;
979 		dev_info->recv_section_size = nvdev->recv_section_size;
980 
981 		memcpy(dev_info->rss_key, nvdev->extension->rss_key,
982 		       NETVSC_HASH_KEYLEN);
983 
984 		prog = netvsc_xdp_get(nvdev);
985 		if (prog) {
986 			bpf_prog_inc(prog);
987 			dev_info->bprog = prog;
988 		}
989 	} else {
990 		dev_info->num_chn = VRSS_CHANNEL_DEFAULT;
991 		dev_info->send_sections = NETVSC_DEFAULT_TX;
992 		dev_info->send_section_size = NETVSC_SEND_SECTION_SIZE;
993 		dev_info->recv_sections = NETVSC_DEFAULT_RX;
994 		dev_info->recv_section_size = NETVSC_RECV_SECTION_SIZE;
995 	}
996 
997 	return dev_info;
998 }
999 
1000 /* Free struct netvsc_device_info */
1001 static void netvsc_devinfo_put(struct netvsc_device_info *dev_info)
1002 {
1003 	if (dev_info->bprog) {
1004 		ASSERT_RTNL();
1005 		bpf_prog_put(dev_info->bprog);
1006 	}
1007 
1008 	kfree(dev_info);
1009 }
1010 
1011 static int netvsc_detach(struct net_device *ndev,
1012 			 struct netvsc_device *nvdev)
1013 {
1014 	struct net_device_context *ndev_ctx = netdev_priv(ndev);
1015 	struct hv_device *hdev = ndev_ctx->device_ctx;
1016 	int ret;
1017 
1018 	/* Don't try continuing to try and setup sub channels */
1019 	if (cancel_work_sync(&nvdev->subchan_work))
1020 		nvdev->num_chn = 1;
1021 
1022 	netvsc_xdp_set(ndev, NULL, NULL, nvdev);
1023 
1024 	/* If device was up (receiving) then shutdown */
1025 	if (netif_running(ndev)) {
1026 		netvsc_tx_disable(nvdev, ndev);
1027 
1028 		ret = rndis_filter_close(nvdev);
1029 		if (ret) {
1030 			netdev_err(ndev,
1031 				   "unable to close device (ret %d).\n", ret);
1032 			return ret;
1033 		}
1034 
1035 		ret = netvsc_wait_until_empty(nvdev);
1036 		if (ret) {
1037 			netdev_err(ndev,
1038 				   "Ring buffer not empty after closing rndis\n");
1039 			return ret;
1040 		}
1041 	}
1042 
1043 	netif_device_detach(ndev);
1044 
1045 	rndis_filter_device_remove(hdev, nvdev);
1046 
1047 	return 0;
1048 }
1049 
1050 static int netvsc_attach(struct net_device *ndev,
1051 			 struct netvsc_device_info *dev_info)
1052 {
1053 	struct net_device_context *ndev_ctx = netdev_priv(ndev);
1054 	struct hv_device *hdev = ndev_ctx->device_ctx;
1055 	struct netvsc_device *nvdev;
1056 	struct rndis_device *rdev;
1057 	struct bpf_prog *prog;
1058 	int ret = 0;
1059 
1060 	nvdev = rndis_filter_device_add(hdev, dev_info);
1061 	if (IS_ERR(nvdev))
1062 		return PTR_ERR(nvdev);
1063 
1064 	if (nvdev->num_chn > 1) {
1065 		ret = rndis_set_subchannel(ndev, nvdev, dev_info);
1066 
1067 		/* if unavailable, just proceed with one queue */
1068 		if (ret) {
1069 			nvdev->max_chn = 1;
1070 			nvdev->num_chn = 1;
1071 		}
1072 	}
1073 
1074 	prog = dev_info->bprog;
1075 	if (prog) {
1076 		bpf_prog_inc(prog);
1077 		ret = netvsc_xdp_set(ndev, prog, NULL, nvdev);
1078 		if (ret) {
1079 			bpf_prog_put(prog);
1080 			goto err1;
1081 		}
1082 	}
1083 
1084 	/* In any case device is now ready */
1085 	nvdev->tx_disable = false;
1086 	netif_device_attach(ndev);
1087 
1088 	/* Note: enable and attach happen when sub-channels setup */
1089 	netif_carrier_off(ndev);
1090 
1091 	if (netif_running(ndev)) {
1092 		ret = rndis_filter_open(nvdev);
1093 		if (ret)
1094 			goto err2;
1095 
1096 		rdev = nvdev->extension;
1097 		if (!rdev->link_state)
1098 			netif_carrier_on(ndev);
1099 	}
1100 
1101 	return 0;
1102 
1103 err2:
1104 	netif_device_detach(ndev);
1105 
1106 err1:
1107 	rndis_filter_device_remove(hdev, nvdev);
1108 
1109 	return ret;
1110 }
1111 
1112 static int netvsc_set_channels(struct net_device *net,
1113 			       struct ethtool_channels *channels)
1114 {
1115 	struct net_device_context *net_device_ctx = netdev_priv(net);
1116 	struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
1117 	unsigned int orig, count = channels->combined_count;
1118 	struct netvsc_device_info *device_info;
1119 	int ret;
1120 
1121 	/* We do not support separate count for rx, tx, or other */
1122 	if (count == 0 ||
1123 	    channels->rx_count || channels->tx_count || channels->other_count)
1124 		return -EINVAL;
1125 
1126 	if (!nvdev || nvdev->destroy)
1127 		return -ENODEV;
1128 
1129 	if (nvdev->nvsp_version < NVSP_PROTOCOL_VERSION_5)
1130 		return -EINVAL;
1131 
1132 	if (count > nvdev->max_chn)
1133 		return -EINVAL;
1134 
1135 	orig = nvdev->num_chn;
1136 
1137 	device_info = netvsc_devinfo_get(nvdev);
1138 
1139 	if (!device_info)
1140 		return -ENOMEM;
1141 
1142 	device_info->num_chn = count;
1143 
1144 	ret = netvsc_detach(net, nvdev);
1145 	if (ret)
1146 		goto out;
1147 
1148 	ret = netvsc_attach(net, device_info);
1149 	if (ret) {
1150 		device_info->num_chn = orig;
1151 		if (netvsc_attach(net, device_info))
1152 			netdev_err(net, "restoring channel setting failed\n");
1153 	}
1154 
1155 out:
1156 	netvsc_devinfo_put(device_info);
1157 	return ret;
1158 }
1159 
1160 static void netvsc_init_settings(struct net_device *dev)
1161 {
1162 	struct net_device_context *ndc = netdev_priv(dev);
1163 
1164 	ndc->l4_hash = HV_DEFAULT_L4HASH;
1165 
1166 	ndc->speed = SPEED_UNKNOWN;
1167 	ndc->duplex = DUPLEX_FULL;
1168 
1169 	dev->features = NETIF_F_LRO;
1170 }
1171 
1172 static int netvsc_get_link_ksettings(struct net_device *dev,
1173 				     struct ethtool_link_ksettings *cmd)
1174 {
1175 	struct net_device_context *ndc = netdev_priv(dev);
1176 	struct net_device *vf_netdev;
1177 
1178 	vf_netdev = rtnl_dereference(ndc->vf_netdev);
1179 
1180 	if (vf_netdev)
1181 		return __ethtool_get_link_ksettings(vf_netdev, cmd);
1182 
1183 	cmd->base.speed = ndc->speed;
1184 	cmd->base.duplex = ndc->duplex;
1185 	cmd->base.port = PORT_OTHER;
1186 
1187 	return 0;
1188 }
1189 
1190 static int netvsc_set_link_ksettings(struct net_device *dev,
1191 				     const struct ethtool_link_ksettings *cmd)
1192 {
1193 	struct net_device_context *ndc = netdev_priv(dev);
1194 	struct net_device *vf_netdev = rtnl_dereference(ndc->vf_netdev);
1195 
1196 	if (vf_netdev) {
1197 		if (!vf_netdev->ethtool_ops->set_link_ksettings)
1198 			return -EOPNOTSUPP;
1199 
1200 		return vf_netdev->ethtool_ops->set_link_ksettings(vf_netdev,
1201 								  cmd);
1202 	}
1203 
1204 	return ethtool_virtdev_set_link_ksettings(dev, cmd,
1205 						  &ndc->speed, &ndc->duplex);
1206 }
1207 
1208 static int netvsc_change_mtu(struct net_device *ndev, int mtu)
1209 {
1210 	struct net_device_context *ndevctx = netdev_priv(ndev);
1211 	struct net_device *vf_netdev = rtnl_dereference(ndevctx->vf_netdev);
1212 	struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
1213 	int orig_mtu = ndev->mtu;
1214 	struct netvsc_device_info *device_info;
1215 	int ret = 0;
1216 
1217 	if (!nvdev || nvdev->destroy)
1218 		return -ENODEV;
1219 
1220 	device_info = netvsc_devinfo_get(nvdev);
1221 
1222 	if (!device_info)
1223 		return -ENOMEM;
1224 
1225 	/* Change MTU of underlying VF netdev first. */
1226 	if (vf_netdev) {
1227 		ret = dev_set_mtu(vf_netdev, mtu);
1228 		if (ret)
1229 			goto out;
1230 	}
1231 
1232 	ret = netvsc_detach(ndev, nvdev);
1233 	if (ret)
1234 		goto rollback_vf;
1235 
1236 	WRITE_ONCE(ndev->mtu, mtu);
1237 
1238 	ret = netvsc_attach(ndev, device_info);
1239 	if (!ret)
1240 		goto out;
1241 
1242 	/* Attempt rollback to original MTU */
1243 	WRITE_ONCE(ndev->mtu, orig_mtu);
1244 
1245 	if (netvsc_attach(ndev, device_info))
1246 		netdev_err(ndev, "restoring mtu failed\n");
1247 rollback_vf:
1248 	if (vf_netdev)
1249 		dev_set_mtu(vf_netdev, orig_mtu);
1250 
1251 out:
1252 	netvsc_devinfo_put(device_info);
1253 	return ret;
1254 }
1255 
1256 static void netvsc_get_vf_stats(struct net_device *net,
1257 				struct netvsc_vf_pcpu_stats *tot)
1258 {
1259 	struct net_device_context *ndev_ctx = netdev_priv(net);
1260 	int i;
1261 
1262 	memset(tot, 0, sizeof(*tot));
1263 
1264 	for_each_possible_cpu(i) {
1265 		const struct netvsc_vf_pcpu_stats *stats
1266 			= per_cpu_ptr(ndev_ctx->vf_stats, i);
1267 		u64 rx_packets, rx_bytes, tx_packets, tx_bytes;
1268 		unsigned int start;
1269 
1270 		do {
1271 			start = u64_stats_fetch_begin(&stats->syncp);
1272 			rx_packets = stats->rx_packets;
1273 			tx_packets = stats->tx_packets;
1274 			rx_bytes = stats->rx_bytes;
1275 			tx_bytes = stats->tx_bytes;
1276 		} while (u64_stats_fetch_retry(&stats->syncp, start));
1277 
1278 		tot->rx_packets += rx_packets;
1279 		tot->tx_packets += tx_packets;
1280 		tot->rx_bytes   += rx_bytes;
1281 		tot->tx_bytes   += tx_bytes;
1282 		tot->tx_dropped += stats->tx_dropped;
1283 	}
1284 }
1285 
1286 static void netvsc_get_pcpu_stats(struct net_device *net,
1287 				  struct netvsc_ethtool_pcpu_stats *pcpu_tot)
1288 {
1289 	struct net_device_context *ndev_ctx = netdev_priv(net);
1290 	struct netvsc_device *nvdev = rcu_dereference_rtnl(ndev_ctx->nvdev);
1291 	int i;
1292 
1293 	/* fetch percpu stats of vf */
1294 	for_each_possible_cpu(i) {
1295 		const struct netvsc_vf_pcpu_stats *stats =
1296 			per_cpu_ptr(ndev_ctx->vf_stats, i);
1297 		struct netvsc_ethtool_pcpu_stats *this_tot = &pcpu_tot[i];
1298 		unsigned int start;
1299 
1300 		do {
1301 			start = u64_stats_fetch_begin(&stats->syncp);
1302 			this_tot->vf_rx_packets = stats->rx_packets;
1303 			this_tot->vf_tx_packets = stats->tx_packets;
1304 			this_tot->vf_rx_bytes = stats->rx_bytes;
1305 			this_tot->vf_tx_bytes = stats->tx_bytes;
1306 		} while (u64_stats_fetch_retry(&stats->syncp, start));
1307 		this_tot->rx_packets = this_tot->vf_rx_packets;
1308 		this_tot->tx_packets = this_tot->vf_tx_packets;
1309 		this_tot->rx_bytes   = this_tot->vf_rx_bytes;
1310 		this_tot->tx_bytes   = this_tot->vf_tx_bytes;
1311 	}
1312 
1313 	/* fetch percpu stats of netvsc */
1314 	for (i = 0; i < nvdev->num_chn; i++) {
1315 		const struct netvsc_channel *nvchan = &nvdev->chan_table[i];
1316 		const struct netvsc_stats_tx *tx_stats;
1317 		const struct netvsc_stats_rx *rx_stats;
1318 		struct netvsc_ethtool_pcpu_stats *this_tot =
1319 			&pcpu_tot[nvchan->channel->target_cpu];
1320 		u64 packets, bytes;
1321 		unsigned int start;
1322 
1323 		tx_stats = &nvchan->tx_stats;
1324 		do {
1325 			start = u64_stats_fetch_begin(&tx_stats->syncp);
1326 			packets = tx_stats->packets;
1327 			bytes = tx_stats->bytes;
1328 		} while (u64_stats_fetch_retry(&tx_stats->syncp, start));
1329 
1330 		this_tot->tx_bytes	+= bytes;
1331 		this_tot->tx_packets	+= packets;
1332 
1333 		rx_stats = &nvchan->rx_stats;
1334 		do {
1335 			start = u64_stats_fetch_begin(&rx_stats->syncp);
1336 			packets = rx_stats->packets;
1337 			bytes = rx_stats->bytes;
1338 		} while (u64_stats_fetch_retry(&rx_stats->syncp, start));
1339 
1340 		this_tot->rx_bytes	+= bytes;
1341 		this_tot->rx_packets	+= packets;
1342 	}
1343 }
1344 
1345 static void netvsc_get_stats64(struct net_device *net,
1346 			       struct rtnl_link_stats64 *t)
1347 {
1348 	struct net_device_context *ndev_ctx = netdev_priv(net);
1349 	struct netvsc_device *nvdev;
1350 	struct netvsc_vf_pcpu_stats vf_tot;
1351 	int i;
1352 
1353 	rcu_read_lock();
1354 
1355 	nvdev = rcu_dereference(ndev_ctx->nvdev);
1356 	if (!nvdev)
1357 		goto out;
1358 
1359 	netdev_stats_to_stats64(t, &net->stats);
1360 
1361 	netvsc_get_vf_stats(net, &vf_tot);
1362 	t->rx_packets += vf_tot.rx_packets;
1363 	t->tx_packets += vf_tot.tx_packets;
1364 	t->rx_bytes   += vf_tot.rx_bytes;
1365 	t->tx_bytes   += vf_tot.tx_bytes;
1366 	t->tx_dropped += vf_tot.tx_dropped;
1367 
1368 	for (i = 0; i < nvdev->num_chn; i++) {
1369 		const struct netvsc_channel *nvchan = &nvdev->chan_table[i];
1370 		const struct netvsc_stats_tx *tx_stats;
1371 		const struct netvsc_stats_rx *rx_stats;
1372 		u64 packets, bytes, multicast;
1373 		unsigned int start;
1374 
1375 		tx_stats = &nvchan->tx_stats;
1376 		do {
1377 			start = u64_stats_fetch_begin(&tx_stats->syncp);
1378 			packets = tx_stats->packets;
1379 			bytes = tx_stats->bytes;
1380 		} while (u64_stats_fetch_retry(&tx_stats->syncp, start));
1381 
1382 		t->tx_bytes	+= bytes;
1383 		t->tx_packets	+= packets;
1384 
1385 		rx_stats = &nvchan->rx_stats;
1386 		do {
1387 			start = u64_stats_fetch_begin(&rx_stats->syncp);
1388 			packets = rx_stats->packets;
1389 			bytes = rx_stats->bytes;
1390 			multicast = rx_stats->multicast + rx_stats->broadcast;
1391 		} while (u64_stats_fetch_retry(&rx_stats->syncp, start));
1392 
1393 		t->rx_bytes	+= bytes;
1394 		t->rx_packets	+= packets;
1395 		t->multicast	+= multicast;
1396 	}
1397 out:
1398 	rcu_read_unlock();
1399 }
1400 
1401 static int netvsc_set_mac_addr(struct net_device *ndev, void *p)
1402 {
1403 	struct net_device_context *ndc = netdev_priv(ndev);
1404 	struct net_device *vf_netdev = rtnl_dereference(ndc->vf_netdev);
1405 	struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
1406 	struct sockaddr *addr = p;
1407 	int err;
1408 
1409 	err = eth_prepare_mac_addr_change(ndev, p);
1410 	if (err)
1411 		return err;
1412 
1413 	if (!nvdev)
1414 		return -ENODEV;
1415 
1416 	if (vf_netdev) {
1417 		err = dev_set_mac_address(vf_netdev, addr, NULL);
1418 		if (err)
1419 			return err;
1420 	}
1421 
1422 	err = rndis_filter_set_device_mac(nvdev, addr->sa_data);
1423 	if (!err) {
1424 		eth_commit_mac_addr_change(ndev, p);
1425 	} else if (vf_netdev) {
1426 		/* rollback change on VF */
1427 		memcpy(addr->sa_data, ndev->dev_addr, ETH_ALEN);
1428 		dev_set_mac_address(vf_netdev, addr, NULL);
1429 	}
1430 
1431 	return err;
1432 }
1433 
1434 static const struct {
1435 	char name[ETH_GSTRING_LEN];
1436 	u16 offset;
1437 } netvsc_stats[] = {
1438 	{ "tx_scattered", offsetof(struct netvsc_ethtool_stats, tx_scattered) },
1439 	{ "tx_no_memory", offsetof(struct netvsc_ethtool_stats, tx_no_memory) },
1440 	{ "tx_no_space",  offsetof(struct netvsc_ethtool_stats, tx_no_space) },
1441 	{ "tx_too_big",	  offsetof(struct netvsc_ethtool_stats, tx_too_big) },
1442 	{ "tx_busy",	  offsetof(struct netvsc_ethtool_stats, tx_busy) },
1443 	{ "tx_send_full", offsetof(struct netvsc_ethtool_stats, tx_send_full) },
1444 	{ "rx_comp_busy", offsetof(struct netvsc_ethtool_stats, rx_comp_busy) },
1445 	{ "rx_no_memory", offsetof(struct netvsc_ethtool_stats, rx_no_memory) },
1446 	{ "stop_queue", offsetof(struct netvsc_ethtool_stats, stop_queue) },
1447 	{ "wake_queue", offsetof(struct netvsc_ethtool_stats, wake_queue) },
1448 	{ "vlan_error", offsetof(struct netvsc_ethtool_stats, vlan_error) },
1449 }, pcpu_stats[] = {
1450 	{ "cpu%u_rx_packets",
1451 		offsetof(struct netvsc_ethtool_pcpu_stats, rx_packets) },
1452 	{ "cpu%u_rx_bytes",
1453 		offsetof(struct netvsc_ethtool_pcpu_stats, rx_bytes) },
1454 	{ "cpu%u_tx_packets",
1455 		offsetof(struct netvsc_ethtool_pcpu_stats, tx_packets) },
1456 	{ "cpu%u_tx_bytes",
1457 		offsetof(struct netvsc_ethtool_pcpu_stats, tx_bytes) },
1458 	{ "cpu%u_vf_rx_packets",
1459 		offsetof(struct netvsc_ethtool_pcpu_stats, vf_rx_packets) },
1460 	{ "cpu%u_vf_rx_bytes",
1461 		offsetof(struct netvsc_ethtool_pcpu_stats, vf_rx_bytes) },
1462 	{ "cpu%u_vf_tx_packets",
1463 		offsetof(struct netvsc_ethtool_pcpu_stats, vf_tx_packets) },
1464 	{ "cpu%u_vf_tx_bytes",
1465 		offsetof(struct netvsc_ethtool_pcpu_stats, vf_tx_bytes) },
1466 }, vf_stats[] = {
1467 	{ "vf_rx_packets", offsetof(struct netvsc_vf_pcpu_stats, rx_packets) },
1468 	{ "vf_rx_bytes",   offsetof(struct netvsc_vf_pcpu_stats, rx_bytes) },
1469 	{ "vf_tx_packets", offsetof(struct netvsc_vf_pcpu_stats, tx_packets) },
1470 	{ "vf_tx_bytes",   offsetof(struct netvsc_vf_pcpu_stats, tx_bytes) },
1471 	{ "vf_tx_dropped", offsetof(struct netvsc_vf_pcpu_stats, tx_dropped) },
1472 };
1473 
1474 #define NETVSC_GLOBAL_STATS_LEN	ARRAY_SIZE(netvsc_stats)
1475 #define NETVSC_VF_STATS_LEN	ARRAY_SIZE(vf_stats)
1476 
1477 /* statistics per queue (rx/tx packets/bytes) */
1478 #define NETVSC_PCPU_STATS_LEN (num_present_cpus() * ARRAY_SIZE(pcpu_stats))
1479 
1480 /* 8 statistics per queue (rx/tx packets/bytes, XDP actions) */
1481 #define NETVSC_QUEUE_STATS_LEN(dev) ((dev)->num_chn * 8)
1482 
1483 static int netvsc_get_sset_count(struct net_device *dev, int string_set)
1484 {
1485 	struct net_device_context *ndc = netdev_priv(dev);
1486 	struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
1487 
1488 	if (!nvdev)
1489 		return -ENODEV;
1490 
1491 	switch (string_set) {
1492 	case ETH_SS_STATS:
1493 		return NETVSC_GLOBAL_STATS_LEN
1494 			+ NETVSC_VF_STATS_LEN
1495 			+ NETVSC_QUEUE_STATS_LEN(nvdev)
1496 			+ NETVSC_PCPU_STATS_LEN;
1497 	default:
1498 		return -EINVAL;
1499 	}
1500 }
1501 
1502 static void netvsc_get_ethtool_stats(struct net_device *dev,
1503 				     struct ethtool_stats *stats, u64 *data)
1504 {
1505 	struct net_device_context *ndc = netdev_priv(dev);
1506 	struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
1507 	const void *nds = &ndc->eth_stats;
1508 	const struct netvsc_stats_tx *tx_stats;
1509 	const struct netvsc_stats_rx *rx_stats;
1510 	struct netvsc_vf_pcpu_stats sum;
1511 	struct netvsc_ethtool_pcpu_stats *pcpu_sum;
1512 	unsigned int start;
1513 	u64 packets, bytes;
1514 	u64 xdp_drop;
1515 	u64 xdp_redirect;
1516 	u64 xdp_tx;
1517 	u64 xdp_xmit;
1518 	int i, j, cpu;
1519 
1520 	if (!nvdev)
1521 		return;
1522 
1523 	for (i = 0; i < NETVSC_GLOBAL_STATS_LEN; i++)
1524 		data[i] = *(unsigned long *)(nds + netvsc_stats[i].offset);
1525 
1526 	netvsc_get_vf_stats(dev, &sum);
1527 	for (j = 0; j < NETVSC_VF_STATS_LEN; j++)
1528 		data[i++] = *(u64 *)((void *)&sum + vf_stats[j].offset);
1529 
1530 	for (j = 0; j < nvdev->num_chn; j++) {
1531 		tx_stats = &nvdev->chan_table[j].tx_stats;
1532 
1533 		do {
1534 			start = u64_stats_fetch_begin(&tx_stats->syncp);
1535 			packets = tx_stats->packets;
1536 			bytes = tx_stats->bytes;
1537 			xdp_xmit = tx_stats->xdp_xmit;
1538 		} while (u64_stats_fetch_retry(&tx_stats->syncp, start));
1539 		data[i++] = packets;
1540 		data[i++] = bytes;
1541 		data[i++] = xdp_xmit;
1542 
1543 		rx_stats = &nvdev->chan_table[j].rx_stats;
1544 		do {
1545 			start = u64_stats_fetch_begin(&rx_stats->syncp);
1546 			packets = rx_stats->packets;
1547 			bytes = rx_stats->bytes;
1548 			xdp_drop = rx_stats->xdp_drop;
1549 			xdp_redirect = rx_stats->xdp_redirect;
1550 			xdp_tx = rx_stats->xdp_tx;
1551 		} while (u64_stats_fetch_retry(&rx_stats->syncp, start));
1552 		data[i++] = packets;
1553 		data[i++] = bytes;
1554 		data[i++] = xdp_drop;
1555 		data[i++] = xdp_redirect;
1556 		data[i++] = xdp_tx;
1557 	}
1558 
1559 	pcpu_sum = kvmalloc_array(num_possible_cpus(),
1560 				  sizeof(struct netvsc_ethtool_pcpu_stats),
1561 				  GFP_KERNEL);
1562 	if (!pcpu_sum)
1563 		return;
1564 
1565 	netvsc_get_pcpu_stats(dev, pcpu_sum);
1566 	for_each_present_cpu(cpu) {
1567 		struct netvsc_ethtool_pcpu_stats *this_sum = &pcpu_sum[cpu];
1568 
1569 		for (j = 0; j < ARRAY_SIZE(pcpu_stats); j++)
1570 			data[i++] = *(u64 *)((void *)this_sum
1571 					     + pcpu_stats[j].offset);
1572 	}
1573 	kvfree(pcpu_sum);
1574 }
1575 
1576 static void netvsc_get_strings(struct net_device *dev, u32 stringset, u8 *data)
1577 {
1578 	struct net_device_context *ndc = netdev_priv(dev);
1579 	struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
1580 	u8 *p = data;
1581 	int i, cpu;
1582 
1583 	if (!nvdev)
1584 		return;
1585 
1586 	switch (stringset) {
1587 	case ETH_SS_STATS:
1588 		for (i = 0; i < ARRAY_SIZE(netvsc_stats); i++)
1589 			ethtool_puts(&p, netvsc_stats[i].name);
1590 
1591 		for (i = 0; i < ARRAY_SIZE(vf_stats); i++)
1592 			ethtool_puts(&p, vf_stats[i].name);
1593 
1594 		for (i = 0; i < nvdev->num_chn; i++) {
1595 			ethtool_sprintf(&p, "tx_queue_%u_packets", i);
1596 			ethtool_sprintf(&p, "tx_queue_%u_bytes", i);
1597 			ethtool_sprintf(&p, "tx_queue_%u_xdp_xmit", i);
1598 			ethtool_sprintf(&p, "rx_queue_%u_packets", i);
1599 			ethtool_sprintf(&p, "rx_queue_%u_bytes", i);
1600 			ethtool_sprintf(&p, "rx_queue_%u_xdp_drop", i);
1601 			ethtool_sprintf(&p, "rx_queue_%u_xdp_redirect", i);
1602 			ethtool_sprintf(&p, "rx_queue_%u_xdp_tx", i);
1603 		}
1604 
1605 		for_each_present_cpu(cpu) {
1606 			for (i = 0; i < ARRAY_SIZE(pcpu_stats); i++)
1607 				ethtool_sprintf(&p, pcpu_stats[i].name, cpu);
1608 		}
1609 
1610 		break;
1611 	}
1612 }
1613 
1614 static int
1615 netvsc_get_rss_hash_opts(struct net_device_context *ndc,
1616 			 struct ethtool_rxnfc *info)
1617 {
1618 	const u32 l4_flag = RXH_L4_B_0_1 | RXH_L4_B_2_3;
1619 
1620 	info->data = RXH_IP_SRC | RXH_IP_DST;
1621 
1622 	switch (info->flow_type) {
1623 	case TCP_V4_FLOW:
1624 		if (ndc->l4_hash & HV_TCP4_L4HASH)
1625 			info->data |= l4_flag;
1626 
1627 		break;
1628 
1629 	case TCP_V6_FLOW:
1630 		if (ndc->l4_hash & HV_TCP6_L4HASH)
1631 			info->data |= l4_flag;
1632 
1633 		break;
1634 
1635 	case UDP_V4_FLOW:
1636 		if (ndc->l4_hash & HV_UDP4_L4HASH)
1637 			info->data |= l4_flag;
1638 
1639 		break;
1640 
1641 	case UDP_V6_FLOW:
1642 		if (ndc->l4_hash & HV_UDP6_L4HASH)
1643 			info->data |= l4_flag;
1644 
1645 		break;
1646 
1647 	case IPV4_FLOW:
1648 	case IPV6_FLOW:
1649 		break;
1650 	default:
1651 		info->data = 0;
1652 		break;
1653 	}
1654 
1655 	return 0;
1656 }
1657 
1658 static int
1659 netvsc_get_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info,
1660 		 u32 *rules)
1661 {
1662 	struct net_device_context *ndc = netdev_priv(dev);
1663 	struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
1664 
1665 	if (!nvdev)
1666 		return -ENODEV;
1667 
1668 	switch (info->cmd) {
1669 	case ETHTOOL_GRXRINGS:
1670 		info->data = nvdev->num_chn;
1671 		return 0;
1672 
1673 	case ETHTOOL_GRXFH:
1674 		return netvsc_get_rss_hash_opts(ndc, info);
1675 	}
1676 	return -EOPNOTSUPP;
1677 }
1678 
1679 static int netvsc_set_rss_hash_opts(struct net_device_context *ndc,
1680 				    struct ethtool_rxnfc *info)
1681 {
1682 	if (info->data == (RXH_IP_SRC | RXH_IP_DST |
1683 			   RXH_L4_B_0_1 | RXH_L4_B_2_3)) {
1684 		switch (info->flow_type) {
1685 		case TCP_V4_FLOW:
1686 			ndc->l4_hash |= HV_TCP4_L4HASH;
1687 			break;
1688 
1689 		case TCP_V6_FLOW:
1690 			ndc->l4_hash |= HV_TCP6_L4HASH;
1691 			break;
1692 
1693 		case UDP_V4_FLOW:
1694 			ndc->l4_hash |= HV_UDP4_L4HASH;
1695 			break;
1696 
1697 		case UDP_V6_FLOW:
1698 			ndc->l4_hash |= HV_UDP6_L4HASH;
1699 			break;
1700 
1701 		default:
1702 			return -EOPNOTSUPP;
1703 		}
1704 
1705 		return 0;
1706 	}
1707 
1708 	if (info->data == (RXH_IP_SRC | RXH_IP_DST)) {
1709 		switch (info->flow_type) {
1710 		case TCP_V4_FLOW:
1711 			ndc->l4_hash &= ~HV_TCP4_L4HASH;
1712 			break;
1713 
1714 		case TCP_V6_FLOW:
1715 			ndc->l4_hash &= ~HV_TCP6_L4HASH;
1716 			break;
1717 
1718 		case UDP_V4_FLOW:
1719 			ndc->l4_hash &= ~HV_UDP4_L4HASH;
1720 			break;
1721 
1722 		case UDP_V6_FLOW:
1723 			ndc->l4_hash &= ~HV_UDP6_L4HASH;
1724 			break;
1725 
1726 		default:
1727 			return -EOPNOTSUPP;
1728 		}
1729 
1730 		return 0;
1731 	}
1732 
1733 	return -EOPNOTSUPP;
1734 }
1735 
1736 static int
1737 netvsc_set_rxnfc(struct net_device *ndev, struct ethtool_rxnfc *info)
1738 {
1739 	struct net_device_context *ndc = netdev_priv(ndev);
1740 
1741 	if (info->cmd == ETHTOOL_SRXFH)
1742 		return netvsc_set_rss_hash_opts(ndc, info);
1743 
1744 	return -EOPNOTSUPP;
1745 }
1746 
1747 static u32 netvsc_get_rxfh_key_size(struct net_device *dev)
1748 {
1749 	return NETVSC_HASH_KEYLEN;
1750 }
1751 
1752 static u32 netvsc_rss_indir_size(struct net_device *dev)
1753 {
1754 	struct net_device_context *ndc = netdev_priv(dev);
1755 
1756 	return ndc->rx_table_sz;
1757 }
1758 
1759 static int netvsc_get_rxfh(struct net_device *dev,
1760 			   struct ethtool_rxfh_param *rxfh)
1761 {
1762 	struct net_device_context *ndc = netdev_priv(dev);
1763 	struct netvsc_device *ndev = rtnl_dereference(ndc->nvdev);
1764 	struct rndis_device *rndis_dev;
1765 	int i;
1766 
1767 	if (!ndev)
1768 		return -ENODEV;
1769 
1770 	rxfh->hfunc = ETH_RSS_HASH_TOP;	/* Toeplitz */
1771 
1772 	rndis_dev = ndev->extension;
1773 	if (rxfh->indir) {
1774 		for (i = 0; i < ndc->rx_table_sz; i++)
1775 			rxfh->indir[i] = ndc->rx_table[i];
1776 	}
1777 
1778 	if (rxfh->key)
1779 		memcpy(rxfh->key, rndis_dev->rss_key, NETVSC_HASH_KEYLEN);
1780 
1781 	return 0;
1782 }
1783 
1784 static int netvsc_set_rxfh(struct net_device *dev,
1785 			   struct ethtool_rxfh_param *rxfh,
1786 			   struct netlink_ext_ack *extack)
1787 {
1788 	struct net_device_context *ndc = netdev_priv(dev);
1789 	struct netvsc_device *ndev = rtnl_dereference(ndc->nvdev);
1790 	struct rndis_device *rndis_dev;
1791 	u8 *key = rxfh->key;
1792 	int i;
1793 
1794 	if (!ndev)
1795 		return -ENODEV;
1796 
1797 	if (rxfh->hfunc != ETH_RSS_HASH_NO_CHANGE &&
1798 	    rxfh->hfunc != ETH_RSS_HASH_TOP)
1799 		return -EOPNOTSUPP;
1800 
1801 	rndis_dev = ndev->extension;
1802 	if (rxfh->indir) {
1803 		for (i = 0; i < ndc->rx_table_sz; i++)
1804 			if (rxfh->indir[i] >= ndev->num_chn)
1805 				return -EINVAL;
1806 
1807 		for (i = 0; i < ndc->rx_table_sz; i++)
1808 			ndc->rx_table[i] = rxfh->indir[i];
1809 	}
1810 
1811 	if (!key) {
1812 		if (!rxfh->indir)
1813 			return 0;
1814 
1815 		key = rndis_dev->rss_key;
1816 	}
1817 
1818 	return rndis_filter_set_rss_param(rndis_dev, key);
1819 }
1820 
1821 /* Hyper-V RNDIS protocol does not have ring in the HW sense.
1822  * It does have pre-allocated receive area which is divided into sections.
1823  */
1824 static void __netvsc_get_ringparam(struct netvsc_device *nvdev,
1825 				   struct ethtool_ringparam *ring)
1826 {
1827 	u32 max_buf_size;
1828 
1829 	ring->rx_pending = nvdev->recv_section_cnt;
1830 	ring->tx_pending = nvdev->send_section_cnt;
1831 
1832 	if (nvdev->nvsp_version <= NVSP_PROTOCOL_VERSION_2)
1833 		max_buf_size = NETVSC_RECEIVE_BUFFER_SIZE_LEGACY;
1834 	else
1835 		max_buf_size = NETVSC_RECEIVE_BUFFER_SIZE;
1836 
1837 	ring->rx_max_pending = max_buf_size / nvdev->recv_section_size;
1838 	ring->tx_max_pending = NETVSC_SEND_BUFFER_SIZE
1839 		/ nvdev->send_section_size;
1840 }
1841 
1842 static void netvsc_get_ringparam(struct net_device *ndev,
1843 				 struct ethtool_ringparam *ring,
1844 				 struct kernel_ethtool_ringparam *kernel_ring,
1845 				 struct netlink_ext_ack *extack)
1846 {
1847 	struct net_device_context *ndevctx = netdev_priv(ndev);
1848 	struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
1849 
1850 	if (!nvdev)
1851 		return;
1852 
1853 	__netvsc_get_ringparam(nvdev, ring);
1854 }
1855 
1856 static int netvsc_set_ringparam(struct net_device *ndev,
1857 				struct ethtool_ringparam *ring,
1858 				struct kernel_ethtool_ringparam *kernel_ring,
1859 				struct netlink_ext_ack *extack)
1860 {
1861 	struct net_device_context *ndevctx = netdev_priv(ndev);
1862 	struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
1863 	struct netvsc_device_info *device_info;
1864 	struct ethtool_ringparam orig;
1865 	u32 new_tx, new_rx;
1866 	int ret = 0;
1867 
1868 	if (!nvdev || nvdev->destroy)
1869 		return -ENODEV;
1870 
1871 	memset(&orig, 0, sizeof(orig));
1872 	__netvsc_get_ringparam(nvdev, &orig);
1873 
1874 	new_tx = clamp_t(u32, ring->tx_pending,
1875 			 NETVSC_MIN_TX_SECTIONS, orig.tx_max_pending);
1876 	new_rx = clamp_t(u32, ring->rx_pending,
1877 			 NETVSC_MIN_RX_SECTIONS, orig.rx_max_pending);
1878 
1879 	if (new_tx == orig.tx_pending &&
1880 	    new_rx == orig.rx_pending)
1881 		return 0;	 /* no change */
1882 
1883 	device_info = netvsc_devinfo_get(nvdev);
1884 
1885 	if (!device_info)
1886 		return -ENOMEM;
1887 
1888 	device_info->send_sections = new_tx;
1889 	device_info->recv_sections = new_rx;
1890 
1891 	ret = netvsc_detach(ndev, nvdev);
1892 	if (ret)
1893 		goto out;
1894 
1895 	ret = netvsc_attach(ndev, device_info);
1896 	if (ret) {
1897 		device_info->send_sections = orig.tx_pending;
1898 		device_info->recv_sections = orig.rx_pending;
1899 
1900 		if (netvsc_attach(ndev, device_info))
1901 			netdev_err(ndev, "restoring ringparam failed");
1902 	}
1903 
1904 out:
1905 	netvsc_devinfo_put(device_info);
1906 	return ret;
1907 }
1908 
1909 static netdev_features_t netvsc_fix_features(struct net_device *ndev,
1910 					     netdev_features_t features)
1911 {
1912 	struct net_device_context *ndevctx = netdev_priv(ndev);
1913 	struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
1914 
1915 	if (!nvdev || nvdev->destroy)
1916 		return features;
1917 
1918 	if ((features & NETIF_F_LRO) && netvsc_xdp_get(nvdev)) {
1919 		features ^= NETIF_F_LRO;
1920 		netdev_info(ndev, "Skip LRO - unsupported with XDP\n");
1921 	}
1922 
1923 	return features;
1924 }
1925 
1926 static int netvsc_set_features(struct net_device *ndev,
1927 			       netdev_features_t features)
1928 {
1929 	netdev_features_t change = features ^ ndev->features;
1930 	struct net_device_context *ndevctx = netdev_priv(ndev);
1931 	struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
1932 	struct net_device *vf_netdev = rtnl_dereference(ndevctx->vf_netdev);
1933 	struct ndis_offload_params offloads;
1934 	int ret = 0;
1935 
1936 	if (!nvdev || nvdev->destroy)
1937 		return -ENODEV;
1938 
1939 	if (!(change & NETIF_F_LRO))
1940 		goto syncvf;
1941 
1942 	memset(&offloads, 0, sizeof(struct ndis_offload_params));
1943 
1944 	if (features & NETIF_F_LRO) {
1945 		offloads.rsc_ip_v4 = NDIS_OFFLOAD_PARAMETERS_RSC_ENABLED;
1946 		offloads.rsc_ip_v6 = NDIS_OFFLOAD_PARAMETERS_RSC_ENABLED;
1947 	} else {
1948 		offloads.rsc_ip_v4 = NDIS_OFFLOAD_PARAMETERS_RSC_DISABLED;
1949 		offloads.rsc_ip_v6 = NDIS_OFFLOAD_PARAMETERS_RSC_DISABLED;
1950 	}
1951 
1952 	ret = rndis_filter_set_offload_params(ndev, nvdev, &offloads);
1953 
1954 	if (ret) {
1955 		features ^= NETIF_F_LRO;
1956 		ndev->features = features;
1957 	}
1958 
1959 syncvf:
1960 	if (!vf_netdev)
1961 		return ret;
1962 
1963 	vf_netdev->wanted_features = features;
1964 	netdev_update_features(vf_netdev);
1965 
1966 	return ret;
1967 }
1968 
1969 static int netvsc_get_regs_len(struct net_device *netdev)
1970 {
1971 	return VRSS_SEND_TAB_SIZE * sizeof(u32);
1972 }
1973 
1974 static void netvsc_get_regs(struct net_device *netdev,
1975 			    struct ethtool_regs *regs, void *p)
1976 {
1977 	struct net_device_context *ndc = netdev_priv(netdev);
1978 	u32 *regs_buff = p;
1979 
1980 	/* increase the version, if buffer format is changed. */
1981 	regs->version = 1;
1982 
1983 	memcpy(regs_buff, ndc->tx_table, VRSS_SEND_TAB_SIZE * sizeof(u32));
1984 }
1985 
1986 static u32 netvsc_get_msglevel(struct net_device *ndev)
1987 {
1988 	struct net_device_context *ndev_ctx = netdev_priv(ndev);
1989 
1990 	return ndev_ctx->msg_enable;
1991 }
1992 
1993 static void netvsc_set_msglevel(struct net_device *ndev, u32 val)
1994 {
1995 	struct net_device_context *ndev_ctx = netdev_priv(ndev);
1996 
1997 	ndev_ctx->msg_enable = val;
1998 }
1999 
2000 static const struct ethtool_ops ethtool_ops = {
2001 	.get_drvinfo	= netvsc_get_drvinfo,
2002 	.get_regs_len	= netvsc_get_regs_len,
2003 	.get_regs	= netvsc_get_regs,
2004 	.get_msglevel	= netvsc_get_msglevel,
2005 	.set_msglevel	= netvsc_set_msglevel,
2006 	.get_link	= ethtool_op_get_link,
2007 	.get_ethtool_stats = netvsc_get_ethtool_stats,
2008 	.get_sset_count = netvsc_get_sset_count,
2009 	.get_strings	= netvsc_get_strings,
2010 	.get_channels   = netvsc_get_channels,
2011 	.set_channels   = netvsc_set_channels,
2012 	.get_ts_info	= ethtool_op_get_ts_info,
2013 	.get_rxnfc	= netvsc_get_rxnfc,
2014 	.set_rxnfc	= netvsc_set_rxnfc,
2015 	.get_rxfh_key_size = netvsc_get_rxfh_key_size,
2016 	.get_rxfh_indir_size = netvsc_rss_indir_size,
2017 	.get_rxfh	= netvsc_get_rxfh,
2018 	.set_rxfh	= netvsc_set_rxfh,
2019 	.get_link_ksettings = netvsc_get_link_ksettings,
2020 	.set_link_ksettings = netvsc_set_link_ksettings,
2021 	.get_ringparam	= netvsc_get_ringparam,
2022 	.set_ringparam	= netvsc_set_ringparam,
2023 };
2024 
2025 static const struct net_device_ops device_ops = {
2026 	.ndo_open =			netvsc_open,
2027 	.ndo_stop =			netvsc_close,
2028 	.ndo_start_xmit =		netvsc_start_xmit,
2029 	.ndo_change_rx_flags =		netvsc_change_rx_flags,
2030 	.ndo_set_rx_mode =		netvsc_set_rx_mode,
2031 	.ndo_fix_features =		netvsc_fix_features,
2032 	.ndo_set_features =		netvsc_set_features,
2033 	.ndo_change_mtu =		netvsc_change_mtu,
2034 	.ndo_validate_addr =		eth_validate_addr,
2035 	.ndo_set_mac_address =		netvsc_set_mac_addr,
2036 	.ndo_select_queue =		netvsc_select_queue,
2037 	.ndo_get_stats64 =		netvsc_get_stats64,
2038 	.ndo_bpf =			netvsc_bpf,
2039 	.ndo_xdp_xmit =			netvsc_ndoxdp_xmit,
2040 };
2041 
2042 /*
2043  * Handle link status changes. For RNDIS_STATUS_NETWORK_CHANGE emulate link
2044  * down/up sequence. In case of RNDIS_STATUS_MEDIA_CONNECT when carrier is
2045  * present send GARP packet to network peers with netif_notify_peers().
2046  */
2047 static void netvsc_link_change(struct work_struct *w)
2048 {
2049 	struct net_device_context *ndev_ctx =
2050 		container_of(w, struct net_device_context, dwork.work);
2051 	struct hv_device *device_obj = ndev_ctx->device_ctx;
2052 	struct net_device *net = hv_get_drvdata(device_obj);
2053 	unsigned long flags, next_reconfig, delay;
2054 	struct netvsc_reconfig *event = NULL;
2055 	struct netvsc_device *net_device;
2056 	struct rndis_device *rdev;
2057 	bool reschedule = false;
2058 
2059 	/* if changes are happening, comeback later */
2060 	if (!rtnl_trylock()) {
2061 		schedule_delayed_work(&ndev_ctx->dwork, LINKCHANGE_INT);
2062 		return;
2063 	}
2064 
2065 	net_device = rtnl_dereference(ndev_ctx->nvdev);
2066 	if (!net_device)
2067 		goto out_unlock;
2068 
2069 	rdev = net_device->extension;
2070 
2071 	next_reconfig = ndev_ctx->last_reconfig + LINKCHANGE_INT;
2072 	if (time_is_after_jiffies(next_reconfig)) {
2073 		/* link_watch only sends one notification with current state
2074 		 * per second, avoid doing reconfig more frequently. Handle
2075 		 * wrap around.
2076 		 */
2077 		delay = next_reconfig - jiffies;
2078 		delay = delay < LINKCHANGE_INT ? delay : LINKCHANGE_INT;
2079 		schedule_delayed_work(&ndev_ctx->dwork, delay);
2080 		goto out_unlock;
2081 	}
2082 	ndev_ctx->last_reconfig = jiffies;
2083 
2084 	spin_lock_irqsave(&ndev_ctx->lock, flags);
2085 	if (!list_empty(&ndev_ctx->reconfig_events)) {
2086 		event = list_first_entry(&ndev_ctx->reconfig_events,
2087 					 struct netvsc_reconfig, list);
2088 		list_del(&event->list);
2089 		reschedule = !list_empty(&ndev_ctx->reconfig_events);
2090 	}
2091 	spin_unlock_irqrestore(&ndev_ctx->lock, flags);
2092 
2093 	if (!event)
2094 		goto out_unlock;
2095 
2096 	switch (event->event) {
2097 		/* Only the following events are possible due to the check in
2098 		 * netvsc_linkstatus_callback()
2099 		 */
2100 	case RNDIS_STATUS_MEDIA_CONNECT:
2101 		if (rdev->link_state) {
2102 			rdev->link_state = false;
2103 			netif_carrier_on(net);
2104 			netvsc_tx_enable(net_device, net);
2105 		} else {
2106 			__netdev_notify_peers(net);
2107 		}
2108 		kfree(event);
2109 		break;
2110 	case RNDIS_STATUS_MEDIA_DISCONNECT:
2111 		if (!rdev->link_state) {
2112 			rdev->link_state = true;
2113 			netif_carrier_off(net);
2114 			netvsc_tx_disable(net_device, net);
2115 		}
2116 		kfree(event);
2117 		break;
2118 	case RNDIS_STATUS_NETWORK_CHANGE:
2119 		/* Only makes sense if carrier is present */
2120 		if (!rdev->link_state) {
2121 			rdev->link_state = true;
2122 			netif_carrier_off(net);
2123 			netvsc_tx_disable(net_device, net);
2124 			event->event = RNDIS_STATUS_MEDIA_CONNECT;
2125 			spin_lock_irqsave(&ndev_ctx->lock, flags);
2126 			list_add(&event->list, &ndev_ctx->reconfig_events);
2127 			spin_unlock_irqrestore(&ndev_ctx->lock, flags);
2128 			reschedule = true;
2129 		}
2130 		break;
2131 	}
2132 
2133 	rtnl_unlock();
2134 
2135 	/* link_watch only sends one notification with current state per
2136 	 * second, handle next reconfig event in 2 seconds.
2137 	 */
2138 	if (reschedule)
2139 		schedule_delayed_work(&ndev_ctx->dwork, LINKCHANGE_INT);
2140 
2141 	return;
2142 
2143 out_unlock:
2144 	rtnl_unlock();
2145 }
2146 
2147 static struct net_device *get_netvsc_byref(struct net_device *vf_netdev)
2148 {
2149 	struct net_device_context *net_device_ctx;
2150 	struct net_device *dev;
2151 
2152 	dev = netdev_master_upper_dev_get(vf_netdev);
2153 	if (!dev || dev->netdev_ops != &device_ops)
2154 		return NULL;	/* not a netvsc device */
2155 
2156 	net_device_ctx = netdev_priv(dev);
2157 	if (!rtnl_dereference(net_device_ctx->nvdev))
2158 		return NULL;	/* device is removed */
2159 
2160 	return dev;
2161 }
2162 
2163 /* Called when VF is injecting data into network stack.
2164  * Change the associated network device from VF to netvsc.
2165  * note: already called with rcu_read_lock
2166  */
2167 static rx_handler_result_t netvsc_vf_handle_frame(struct sk_buff **pskb)
2168 {
2169 	struct sk_buff *skb = *pskb;
2170 	struct net_device *ndev = rcu_dereference(skb->dev->rx_handler_data);
2171 	struct net_device_context *ndev_ctx = netdev_priv(ndev);
2172 	struct netvsc_vf_pcpu_stats *pcpu_stats
2173 		 = this_cpu_ptr(ndev_ctx->vf_stats);
2174 
2175 	skb = skb_share_check(skb, GFP_ATOMIC);
2176 	if (unlikely(!skb))
2177 		return RX_HANDLER_CONSUMED;
2178 
2179 	*pskb = skb;
2180 
2181 	skb->dev = ndev;
2182 
2183 	u64_stats_update_begin(&pcpu_stats->syncp);
2184 	pcpu_stats->rx_packets++;
2185 	pcpu_stats->rx_bytes += skb->len;
2186 	u64_stats_update_end(&pcpu_stats->syncp);
2187 
2188 	return RX_HANDLER_ANOTHER;
2189 }
2190 
2191 static int netvsc_vf_join(struct net_device *vf_netdev,
2192 			  struct net_device *ndev, int context)
2193 {
2194 	struct net_device_context *ndev_ctx = netdev_priv(ndev);
2195 	int ret;
2196 
2197 	ret = netdev_rx_handler_register(vf_netdev,
2198 					 netvsc_vf_handle_frame, ndev);
2199 	if (ret != 0) {
2200 		netdev_err(vf_netdev,
2201 			   "can not register netvsc VF receive handler (err = %d)\n",
2202 			   ret);
2203 		goto rx_handler_failed;
2204 	}
2205 
2206 	ret = netdev_master_upper_dev_link(vf_netdev, ndev,
2207 					   NULL, NULL, NULL);
2208 	if (ret != 0) {
2209 		netdev_err(vf_netdev,
2210 			   "can not set master device %s (err = %d)\n",
2211 			   ndev->name, ret);
2212 		goto upper_link_failed;
2213 	}
2214 
2215 	/* If this registration is called from probe context vf_takeover
2216 	 * is taken care of later in probe itself.
2217 	 */
2218 	if (context == VF_REG_IN_NOTIFIER)
2219 		schedule_delayed_work(&ndev_ctx->vf_takeover, VF_TAKEOVER_INT);
2220 
2221 	call_netdevice_notifiers(NETDEV_JOIN, vf_netdev);
2222 
2223 	netdev_info(vf_netdev, "joined to %s\n", ndev->name);
2224 	return 0;
2225 
2226 upper_link_failed:
2227 	netdev_rx_handler_unregister(vf_netdev);
2228 rx_handler_failed:
2229 	return ret;
2230 }
2231 
2232 static void __netvsc_vf_setup(struct net_device *ndev,
2233 			      struct net_device *vf_netdev)
2234 {
2235 	int ret;
2236 
2237 	/* Align MTU of VF with master */
2238 	ret = dev_set_mtu(vf_netdev, ndev->mtu);
2239 	if (ret)
2240 		netdev_warn(vf_netdev,
2241 			    "unable to change mtu to %u\n", ndev->mtu);
2242 
2243 	/* set multicast etc flags on VF */
2244 	dev_change_flags(vf_netdev, ndev->flags | IFF_SLAVE, NULL);
2245 
2246 	/* sync address list from ndev to VF */
2247 	netif_addr_lock_bh(ndev);
2248 	dev_uc_sync(vf_netdev, ndev);
2249 	dev_mc_sync(vf_netdev, ndev);
2250 	netif_addr_unlock_bh(ndev);
2251 
2252 	if (netif_running(ndev)) {
2253 		ret = dev_open(vf_netdev, NULL);
2254 		if (ret)
2255 			netdev_warn(vf_netdev,
2256 				    "unable to open: %d\n", ret);
2257 	}
2258 }
2259 
2260 /* Setup VF as slave of the synthetic device.
2261  * Runs in workqueue to avoid recursion in netlink callbacks.
2262  */
2263 static void netvsc_vf_setup(struct work_struct *w)
2264 {
2265 	struct net_device_context *ndev_ctx
2266 		= container_of(w, struct net_device_context, vf_takeover.work);
2267 	struct net_device *ndev = hv_get_drvdata(ndev_ctx->device_ctx);
2268 	struct net_device *vf_netdev;
2269 
2270 	if (!rtnl_trylock()) {
2271 		schedule_delayed_work(&ndev_ctx->vf_takeover, 0);
2272 		return;
2273 	}
2274 
2275 	vf_netdev = rtnl_dereference(ndev_ctx->vf_netdev);
2276 	if (vf_netdev)
2277 		__netvsc_vf_setup(ndev, vf_netdev);
2278 
2279 	rtnl_unlock();
2280 }
2281 
2282 /* Find netvsc by VF serial number.
2283  * The PCI hyperv controller records the serial number as the slot kobj name.
2284  */
2285 static struct net_device *get_netvsc_byslot(const struct net_device *vf_netdev)
2286 {
2287 	struct device *parent = vf_netdev->dev.parent;
2288 	struct net_device_context *ndev_ctx;
2289 	struct net_device *ndev;
2290 	struct pci_dev *pdev;
2291 	u32 serial;
2292 
2293 	if (!parent || !dev_is_pci(parent))
2294 		return NULL; /* not a PCI device */
2295 
2296 	pdev = to_pci_dev(parent);
2297 	if (!pdev->slot) {
2298 		netdev_notice(vf_netdev, "no PCI slot information\n");
2299 		return NULL;
2300 	}
2301 
2302 	if (kstrtou32(pci_slot_name(pdev->slot), 10, &serial)) {
2303 		netdev_notice(vf_netdev, "Invalid vf serial:%s\n",
2304 			      pci_slot_name(pdev->slot));
2305 		return NULL;
2306 	}
2307 
2308 	list_for_each_entry(ndev_ctx, &netvsc_dev_list, list) {
2309 		if (!ndev_ctx->vf_alloc)
2310 			continue;
2311 
2312 		if (ndev_ctx->vf_serial != serial)
2313 			continue;
2314 
2315 		ndev = hv_get_drvdata(ndev_ctx->device_ctx);
2316 		if (ndev->addr_len != vf_netdev->addr_len ||
2317 		    memcmp(ndev->perm_addr, vf_netdev->perm_addr,
2318 			   ndev->addr_len) != 0)
2319 			continue;
2320 
2321 		return ndev;
2322 
2323 	}
2324 
2325 	/* Fallback path to check synthetic vf with help of mac addr.
2326 	 * Because this function can be called before vf_netdev is
2327 	 * initialized (NETDEV_POST_INIT) when its perm_addr has not been copied
2328 	 * from dev_addr, also try to match to its dev_addr.
2329 	 * Note: On Hyper-V and Azure, it's not possible to set a MAC address
2330 	 * on a VF that matches to the MAC of a unrelated NETVSC device.
2331 	 */
2332 	list_for_each_entry(ndev_ctx, &netvsc_dev_list, list) {
2333 		ndev = hv_get_drvdata(ndev_ctx->device_ctx);
2334 		if (ether_addr_equal(vf_netdev->perm_addr, ndev->perm_addr) ||
2335 		    ether_addr_equal(vf_netdev->dev_addr, ndev->perm_addr))
2336 			return ndev;
2337 	}
2338 
2339 	netdev_notice(vf_netdev,
2340 		      "no netdev found for vf serial:%u\n", serial);
2341 	return NULL;
2342 }
2343 
2344 static int netvsc_prepare_bonding(struct net_device *vf_netdev)
2345 {
2346 	struct net_device *ndev;
2347 
2348 	ndev = get_netvsc_byslot(vf_netdev);
2349 	if (!ndev)
2350 		return NOTIFY_DONE;
2351 
2352 	/* set slave flag before open to prevent IPv6 addrconf */
2353 	vf_netdev->flags |= IFF_SLAVE;
2354 	return NOTIFY_DONE;
2355 }
2356 
2357 static int netvsc_register_vf(struct net_device *vf_netdev, int context)
2358 {
2359 	struct net_device_context *net_device_ctx;
2360 	struct netvsc_device *netvsc_dev;
2361 	struct bpf_prog *prog;
2362 	struct net_device *ndev;
2363 	int ret;
2364 
2365 	if (vf_netdev->addr_len != ETH_ALEN)
2366 		return NOTIFY_DONE;
2367 
2368 	ndev = get_netvsc_byslot(vf_netdev);
2369 	if (!ndev)
2370 		return NOTIFY_DONE;
2371 
2372 	net_device_ctx = netdev_priv(ndev);
2373 	netvsc_dev = rtnl_dereference(net_device_ctx->nvdev);
2374 	if (!netvsc_dev || rtnl_dereference(net_device_ctx->vf_netdev))
2375 		return NOTIFY_DONE;
2376 
2377 	/* if synthetic interface is a different namespace,
2378 	 * then move the VF to that namespace; join will be
2379 	 * done again in that context.
2380 	 */
2381 	if (!net_eq(dev_net(ndev), dev_net(vf_netdev))) {
2382 		ret = dev_change_net_namespace(vf_netdev,
2383 					       dev_net(ndev), "eth%d");
2384 		if (ret)
2385 			netdev_err(vf_netdev,
2386 				   "could not move to same namespace as %s: %d\n",
2387 				   ndev->name, ret);
2388 		else
2389 			netdev_info(vf_netdev,
2390 				    "VF moved to namespace with: %s\n",
2391 				    ndev->name);
2392 		return NOTIFY_DONE;
2393 	}
2394 
2395 	netdev_info(ndev, "VF registering: %s\n", vf_netdev->name);
2396 
2397 	if (netvsc_vf_join(vf_netdev, ndev, context) != 0)
2398 		return NOTIFY_DONE;
2399 
2400 	dev_hold(vf_netdev);
2401 	rcu_assign_pointer(net_device_ctx->vf_netdev, vf_netdev);
2402 
2403 	if (ndev->needed_headroom < vf_netdev->needed_headroom)
2404 		ndev->needed_headroom = vf_netdev->needed_headroom;
2405 
2406 	vf_netdev->wanted_features = ndev->features;
2407 	netdev_update_features(vf_netdev);
2408 
2409 	prog = netvsc_xdp_get(netvsc_dev);
2410 	netvsc_vf_setxdp(vf_netdev, prog);
2411 
2412 	return NOTIFY_OK;
2413 }
2414 
2415 /* Change the data path when VF UP/DOWN/CHANGE are detected.
2416  *
2417  * Typically a UP or DOWN event is followed by a CHANGE event, so
2418  * net_device_ctx->data_path_is_vf is used to cache the current data path
2419  * to avoid the duplicate call of netvsc_switch_datapath() and the duplicate
2420  * message.
2421  *
2422  * During hibernation, if a VF NIC driver (e.g. mlx5) preserves the network
2423  * interface, there is only the CHANGE event and no UP or DOWN event.
2424  */
2425 static int netvsc_vf_changed(struct net_device *vf_netdev, unsigned long event)
2426 {
2427 	struct net_device_context *net_device_ctx;
2428 	struct netvsc_device *netvsc_dev;
2429 	struct net_device *ndev;
2430 	bool vf_is_up = false;
2431 	int ret;
2432 
2433 	if (event != NETDEV_GOING_DOWN)
2434 		vf_is_up = netif_running(vf_netdev);
2435 
2436 	ndev = get_netvsc_byref(vf_netdev);
2437 	if (!ndev)
2438 		return NOTIFY_DONE;
2439 
2440 	net_device_ctx = netdev_priv(ndev);
2441 	netvsc_dev = rtnl_dereference(net_device_ctx->nvdev);
2442 	if (!netvsc_dev)
2443 		return NOTIFY_DONE;
2444 
2445 	if (net_device_ctx->data_path_is_vf == vf_is_up)
2446 		return NOTIFY_OK;
2447 
2448 	if (vf_is_up && !net_device_ctx->vf_alloc) {
2449 		netdev_info(ndev, "Waiting for the VF association from host\n");
2450 		wait_for_completion(&net_device_ctx->vf_add);
2451 	}
2452 
2453 	ret = netvsc_switch_datapath(ndev, vf_is_up);
2454 
2455 	if (ret) {
2456 		netdev_err(ndev,
2457 			   "Data path failed to switch %s VF: %s, err: %d\n",
2458 			   vf_is_up ? "to" : "from", vf_netdev->name, ret);
2459 		return NOTIFY_DONE;
2460 	} else {
2461 		netdev_info(ndev, "Data path switched %s VF: %s\n",
2462 			    vf_is_up ? "to" : "from", vf_netdev->name);
2463 	}
2464 
2465 	return NOTIFY_OK;
2466 }
2467 
2468 static int netvsc_unregister_vf(struct net_device *vf_netdev)
2469 {
2470 	struct net_device *ndev;
2471 	struct net_device_context *net_device_ctx;
2472 
2473 	ndev = get_netvsc_byref(vf_netdev);
2474 	if (!ndev)
2475 		return NOTIFY_DONE;
2476 
2477 	net_device_ctx = netdev_priv(ndev);
2478 	cancel_delayed_work_sync(&net_device_ctx->vf_takeover);
2479 
2480 	netdev_info(ndev, "VF unregistering: %s\n", vf_netdev->name);
2481 
2482 	netvsc_vf_setxdp(vf_netdev, NULL);
2483 
2484 	reinit_completion(&net_device_ctx->vf_add);
2485 	netdev_rx_handler_unregister(vf_netdev);
2486 	netdev_upper_dev_unlink(vf_netdev, ndev);
2487 	RCU_INIT_POINTER(net_device_ctx->vf_netdev, NULL);
2488 	dev_put(vf_netdev);
2489 
2490 	ndev->needed_headroom = RNDIS_AND_PPI_SIZE;
2491 
2492 	return NOTIFY_OK;
2493 }
2494 
2495 static int check_dev_is_matching_vf(struct net_device *event_ndev)
2496 {
2497 	/* Skip NetVSC interfaces */
2498 	if (event_ndev->netdev_ops == &device_ops)
2499 		return -ENODEV;
2500 
2501 	/* Avoid non-Ethernet type devices */
2502 	if (event_ndev->type != ARPHRD_ETHER)
2503 		return -ENODEV;
2504 
2505 	/* Avoid Vlan dev with same MAC registering as VF */
2506 	if (is_vlan_dev(event_ndev))
2507 		return -ENODEV;
2508 
2509 	/* Avoid Bonding master dev with same MAC registering as VF */
2510 	if (netif_is_bond_master(event_ndev))
2511 		return -ENODEV;
2512 
2513 	return 0;
2514 }
2515 
2516 static int netvsc_probe(struct hv_device *dev,
2517 			const struct hv_vmbus_device_id *dev_id)
2518 {
2519 	struct net_device *net = NULL, *vf_netdev;
2520 	struct net_device_context *net_device_ctx;
2521 	struct netvsc_device_info *device_info = NULL;
2522 	struct netvsc_device *nvdev;
2523 	int ret = -ENOMEM;
2524 
2525 	net = alloc_etherdev_mq(sizeof(struct net_device_context),
2526 				VRSS_CHANNEL_MAX);
2527 	if (!net)
2528 		goto no_net;
2529 
2530 	netif_carrier_off(net);
2531 
2532 	netvsc_init_settings(net);
2533 
2534 	net_device_ctx = netdev_priv(net);
2535 	net_device_ctx->device_ctx = dev;
2536 	net_device_ctx->msg_enable = netif_msg_init(debug, default_msg);
2537 	if (netif_msg_probe(net_device_ctx))
2538 		netdev_dbg(net, "netvsc msg_enable: %d\n",
2539 			   net_device_ctx->msg_enable);
2540 
2541 	hv_set_drvdata(dev, net);
2542 
2543 	INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_link_change);
2544 
2545 	init_completion(&net_device_ctx->vf_add);
2546 	spin_lock_init(&net_device_ctx->lock);
2547 	INIT_LIST_HEAD(&net_device_ctx->reconfig_events);
2548 	INIT_DELAYED_WORK(&net_device_ctx->vf_takeover, netvsc_vf_setup);
2549 
2550 	net_device_ctx->vf_stats
2551 		= netdev_alloc_pcpu_stats(struct netvsc_vf_pcpu_stats);
2552 	if (!net_device_ctx->vf_stats)
2553 		goto no_stats;
2554 
2555 	net->netdev_ops = &device_ops;
2556 	net->ethtool_ops = &ethtool_ops;
2557 	SET_NETDEV_DEV(net, &dev->device);
2558 	dma_set_min_align_mask(&dev->device, HV_HYP_PAGE_SIZE - 1);
2559 
2560 	/* We always need headroom for rndis header */
2561 	net->needed_headroom = RNDIS_AND_PPI_SIZE;
2562 
2563 	/* Initialize the number of queues to be 1, we may change it if more
2564 	 * channels are offered later.
2565 	 */
2566 	netif_set_real_num_tx_queues(net, 1);
2567 	netif_set_real_num_rx_queues(net, 1);
2568 
2569 	/* Notify the netvsc driver of the new device */
2570 	device_info = netvsc_devinfo_get(NULL);
2571 
2572 	if (!device_info) {
2573 		ret = -ENOMEM;
2574 		goto devinfo_failed;
2575 	}
2576 
2577 	/* We must get rtnl lock before scheduling nvdev->subchan_work,
2578 	 * otherwise netvsc_subchan_work() can get rtnl lock first and wait
2579 	 * all subchannels to show up, but that may not happen because
2580 	 * netvsc_probe() can't get rtnl lock and as a result vmbus_onoffer()
2581 	 * -> ... -> device_add() -> ... -> __device_attach() can't get
2582 	 * the device lock, so all the subchannels can't be processed --
2583 	 * finally netvsc_subchan_work() hangs forever.
2584 	 *
2585 	 * The rtnl lock also needs to be held before rndis_filter_device_add()
2586 	 * which advertises nvsp_2_vsc_capability / sriov bit, and triggers
2587 	 * VF NIC offering and registering. If VF NIC finished register_netdev()
2588 	 * earlier it may cause name based config failure.
2589 	 */
2590 	rtnl_lock();
2591 
2592 	nvdev = rndis_filter_device_add(dev, device_info);
2593 	if (IS_ERR(nvdev)) {
2594 		ret = PTR_ERR(nvdev);
2595 		netdev_err(net, "unable to add netvsc device (ret %d)\n", ret);
2596 		goto rndis_failed;
2597 	}
2598 
2599 	eth_hw_addr_set(net, device_info->mac_adr);
2600 
2601 	if (nvdev->num_chn > 1)
2602 		schedule_work(&nvdev->subchan_work);
2603 
2604 	/* hw_features computed in rndis_netdev_set_hwcaps() */
2605 	net->features = net->hw_features |
2606 		NETIF_F_HIGHDMA | NETIF_F_HW_VLAN_CTAG_TX |
2607 		NETIF_F_HW_VLAN_CTAG_RX;
2608 	net->vlan_features = net->features;
2609 
2610 	netdev_lockdep_set_classes(net);
2611 
2612 	net->xdp_features = NETDEV_XDP_ACT_BASIC | NETDEV_XDP_ACT_REDIRECT |
2613 			    NETDEV_XDP_ACT_NDO_XMIT;
2614 
2615 	/* MTU range: 68 - 1500 or 65521 */
2616 	net->min_mtu = NETVSC_MTU_MIN;
2617 	if (nvdev->nvsp_version >= NVSP_PROTOCOL_VERSION_2)
2618 		net->max_mtu = NETVSC_MTU - ETH_HLEN;
2619 	else
2620 		net->max_mtu = ETH_DATA_LEN;
2621 
2622 	nvdev->tx_disable = false;
2623 
2624 	ret = register_netdevice(net);
2625 	if (ret != 0) {
2626 		pr_err("Unable to register netdev.\n");
2627 		goto register_failed;
2628 	}
2629 
2630 	list_add(&net_device_ctx->list, &netvsc_dev_list);
2631 
2632 	/* When the hv_netvsc driver is unloaded and reloaded, the
2633 	 * NET_DEVICE_REGISTER for the vf device is replayed before probe
2634 	 * is complete. This is because register_netdevice_notifier() gets
2635 	 * registered before vmbus_driver_register() so that callback func
2636 	 * is set before probe and we don't miss events like NETDEV_POST_INIT
2637 	 * So, in this section we try to register the matching vf device that
2638 	 * is present as a netdevice, knowing that its register call is not
2639 	 * processed in the netvsc_netdev_notifier(as probing is progress and
2640 	 * get_netvsc_byslot fails).
2641 	 */
2642 	for_each_netdev(dev_net(net), vf_netdev) {
2643 		ret = check_dev_is_matching_vf(vf_netdev);
2644 		if (ret != 0)
2645 			continue;
2646 
2647 		if (net != get_netvsc_byslot(vf_netdev))
2648 			continue;
2649 
2650 		netvsc_prepare_bonding(vf_netdev);
2651 		netvsc_register_vf(vf_netdev, VF_REG_IN_PROBE);
2652 		__netvsc_vf_setup(net, vf_netdev);
2653 		break;
2654 	}
2655 	rtnl_unlock();
2656 
2657 	netvsc_devinfo_put(device_info);
2658 	return 0;
2659 
2660 register_failed:
2661 	rndis_filter_device_remove(dev, nvdev);
2662 rndis_failed:
2663 	rtnl_unlock();
2664 	netvsc_devinfo_put(device_info);
2665 devinfo_failed:
2666 	free_percpu(net_device_ctx->vf_stats);
2667 no_stats:
2668 	hv_set_drvdata(dev, NULL);
2669 	free_netdev(net);
2670 no_net:
2671 	return ret;
2672 }
2673 
2674 static void netvsc_remove(struct hv_device *dev)
2675 {
2676 	struct net_device_context *ndev_ctx;
2677 	struct net_device *vf_netdev, *net;
2678 	struct netvsc_device *nvdev;
2679 
2680 	net = hv_get_drvdata(dev);
2681 	if (net == NULL) {
2682 		dev_err(&dev->device, "No net device to remove\n");
2683 		return;
2684 	}
2685 
2686 	ndev_ctx = netdev_priv(net);
2687 
2688 	cancel_delayed_work_sync(&ndev_ctx->dwork);
2689 
2690 	rtnl_lock();
2691 	nvdev = rtnl_dereference(ndev_ctx->nvdev);
2692 	if (nvdev) {
2693 		cancel_work_sync(&nvdev->subchan_work);
2694 		netvsc_xdp_set(net, NULL, NULL, nvdev);
2695 	}
2696 
2697 	/*
2698 	 * Call to the vsc driver to let it know that the device is being
2699 	 * removed. Also blocks mtu and channel changes.
2700 	 */
2701 	vf_netdev = rtnl_dereference(ndev_ctx->vf_netdev);
2702 	if (vf_netdev)
2703 		netvsc_unregister_vf(vf_netdev);
2704 
2705 	if (nvdev)
2706 		rndis_filter_device_remove(dev, nvdev);
2707 
2708 	unregister_netdevice(net);
2709 	list_del(&ndev_ctx->list);
2710 
2711 	rtnl_unlock();
2712 
2713 	hv_set_drvdata(dev, NULL);
2714 
2715 	free_percpu(ndev_ctx->vf_stats);
2716 	free_netdev(net);
2717 }
2718 
2719 static int netvsc_suspend(struct hv_device *dev)
2720 {
2721 	struct net_device_context *ndev_ctx;
2722 	struct netvsc_device *nvdev;
2723 	struct net_device *net;
2724 	int ret;
2725 
2726 	net = hv_get_drvdata(dev);
2727 
2728 	ndev_ctx = netdev_priv(net);
2729 	cancel_delayed_work_sync(&ndev_ctx->dwork);
2730 
2731 	rtnl_lock();
2732 
2733 	nvdev = rtnl_dereference(ndev_ctx->nvdev);
2734 	if (nvdev == NULL) {
2735 		ret = -ENODEV;
2736 		goto out;
2737 	}
2738 
2739 	/* Save the current config info */
2740 	ndev_ctx->saved_netvsc_dev_info = netvsc_devinfo_get(nvdev);
2741 	if (!ndev_ctx->saved_netvsc_dev_info) {
2742 		ret = -ENOMEM;
2743 		goto out;
2744 	}
2745 	ret = netvsc_detach(net, nvdev);
2746 out:
2747 	rtnl_unlock();
2748 
2749 	return ret;
2750 }
2751 
2752 static int netvsc_resume(struct hv_device *dev)
2753 {
2754 	struct net_device *net = hv_get_drvdata(dev);
2755 	struct net_device_context *net_device_ctx;
2756 	struct netvsc_device_info *device_info;
2757 	int ret;
2758 
2759 	rtnl_lock();
2760 
2761 	net_device_ctx = netdev_priv(net);
2762 
2763 	/* Reset the data path to the netvsc NIC before re-opening the vmbus
2764 	 * channel. Later netvsc_netdev_event() will switch the data path to
2765 	 * the VF upon the UP or CHANGE event.
2766 	 */
2767 	net_device_ctx->data_path_is_vf = false;
2768 	device_info = net_device_ctx->saved_netvsc_dev_info;
2769 
2770 	ret = netvsc_attach(net, device_info);
2771 
2772 	netvsc_devinfo_put(device_info);
2773 	net_device_ctx->saved_netvsc_dev_info = NULL;
2774 
2775 	rtnl_unlock();
2776 
2777 	return ret;
2778 }
2779 static const struct hv_vmbus_device_id id_table[] = {
2780 	/* Network guid */
2781 	{ HV_NIC_GUID, },
2782 	{ },
2783 };
2784 
2785 MODULE_DEVICE_TABLE(vmbus, id_table);
2786 
2787 /* The one and only one */
2788 static struct  hv_driver netvsc_drv = {
2789 	.name = KBUILD_MODNAME,
2790 	.id_table = id_table,
2791 	.probe = netvsc_probe,
2792 	.remove = netvsc_remove,
2793 	.suspend = netvsc_suspend,
2794 	.resume = netvsc_resume,
2795 	.driver = {
2796 		.probe_type = PROBE_FORCE_SYNCHRONOUS,
2797 	},
2798 };
2799 
2800 /*
2801  * On Hyper-V, every VF interface is matched with a corresponding
2802  * synthetic interface. The synthetic interface is presented first
2803  * to the guest. When the corresponding VF instance is registered,
2804  * we will take care of switching the data path.
2805  */
2806 static int netvsc_netdev_event(struct notifier_block *this,
2807 			       unsigned long event, void *ptr)
2808 {
2809 	struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
2810 	int ret = 0;
2811 
2812 	ret = check_dev_is_matching_vf(event_dev);
2813 	if (ret != 0)
2814 		return NOTIFY_DONE;
2815 
2816 	switch (event) {
2817 	case NETDEV_POST_INIT:
2818 		return netvsc_prepare_bonding(event_dev);
2819 	case NETDEV_REGISTER:
2820 		return netvsc_register_vf(event_dev, VF_REG_IN_NOTIFIER);
2821 	case NETDEV_UNREGISTER:
2822 		return netvsc_unregister_vf(event_dev);
2823 	case NETDEV_UP:
2824 	case NETDEV_DOWN:
2825 	case NETDEV_CHANGE:
2826 	case NETDEV_GOING_DOWN:
2827 		return netvsc_vf_changed(event_dev, event);
2828 	default:
2829 		return NOTIFY_DONE;
2830 	}
2831 }
2832 
2833 static struct notifier_block netvsc_netdev_notifier = {
2834 	.notifier_call = netvsc_netdev_event,
2835 };
2836 
2837 static void __exit netvsc_drv_exit(void)
2838 {
2839 	unregister_netdevice_notifier(&netvsc_netdev_notifier);
2840 	vmbus_driver_unregister(&netvsc_drv);
2841 }
2842 
2843 static int __init netvsc_drv_init(void)
2844 {
2845 	int ret;
2846 
2847 	if (ring_size < RING_SIZE_MIN) {
2848 		ring_size = RING_SIZE_MIN;
2849 		pr_info("Increased ring_size to %u (min allowed)\n",
2850 			ring_size);
2851 	}
2852 	netvsc_ring_bytes = VMBUS_RING_SIZE(ring_size * 4096);
2853 
2854 	register_netdevice_notifier(&netvsc_netdev_notifier);
2855 
2856 	ret = vmbus_driver_register(&netvsc_drv);
2857 	if (ret)
2858 		goto err_vmbus_reg;
2859 
2860 	return 0;
2861 
2862 err_vmbus_reg:
2863 	unregister_netdevice_notifier(&netvsc_netdev_notifier);
2864 	return ret;
2865 }
2866 
2867 MODULE_LICENSE("GPL");
2868 MODULE_DESCRIPTION("Microsoft Hyper-V network driver");
2869 
2870 module_init(netvsc_drv_init);
2871 module_exit(netvsc_drv_exit);
2872