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v3.15
 
  1/*
  2 * Copyright (c) 2009, Microsoft Corporation.
  3 *
  4 * This program is free software; you can redistribute it and/or modify it
  5 * under the terms and conditions of the GNU General Public License,
  6 * version 2, as published by the Free Software Foundation.
  7 *
  8 * This program is distributed in the hope it will be useful, but WITHOUT
  9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 10 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 11 * more details.
 12 *
 13 * You should have received a copy of the GNU General Public License along with
 14 * this program; if not, see <http://www.gnu.org/licenses/>.
 15 *
 16 * Authors:
 17 *   Haiyang Zhang <haiyangz@microsoft.com>
 18 *   Hank Janssen  <hjanssen@microsoft.com>
 19 */
 20#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 21
 22#include <linux/init.h>
 23#include <linux/atomic.h>
 
 24#include <linux/module.h>
 25#include <linux/highmem.h>
 26#include <linux/device.h>
 27#include <linux/io.h>
 28#include <linux/delay.h>
 29#include <linux/netdevice.h>
 30#include <linux/inetdevice.h>
 31#include <linux/etherdevice.h>
 
 32#include <linux/skbuff.h>
 33#include <linux/if_vlan.h>
 34#include <linux/in.h>
 35#include <linux/slab.h>
 
 
 
 
 36#include <net/arp.h>
 37#include <net/route.h>
 38#include <net/sock.h>
 39#include <net/pkt_sched.h>
 
 
 40
 41#include "hyperv_net.h"
 42
 43struct net_device_context {
 44	/* point back to our device context */
 45	struct hv_device *device_ctx;
 46	struct delayed_work dwork;
 47	struct work_struct work;
 48};
 49
 50#define RING_SIZE_MIN 64
 51static int ring_size = 128;
 52module_param(ring_size, int, S_IRUGO);
 53MODULE_PARM_DESC(ring_size, "Ring buffer size (# of pages)");
 
 
 
 
 
 
 54
 55static void do_set_multicast(struct work_struct *w)
 
 
 
 
 
 
 56{
 57	struct net_device_context *ndevctx =
 58		container_of(w, struct net_device_context, work);
 59	struct netvsc_device *nvdev;
 60	struct rndis_device *rdev;
 61
 62	nvdev = hv_get_drvdata(ndevctx->device_ctx);
 63	if (nvdev == NULL || nvdev->ndev == NULL)
 64		return;
 65
 66	rdev = nvdev->extension;
 67	if (rdev == NULL)
 68		return;
 
 69
 70	if (nvdev->ndev->flags & IFF_PROMISC)
 71		rndis_filter_set_packet_filter(rdev,
 72			NDIS_PACKET_TYPE_PROMISCUOUS);
 73	else
 74		rndis_filter_set_packet_filter(rdev,
 75			NDIS_PACKET_TYPE_BROADCAST |
 76			NDIS_PACKET_TYPE_ALL_MULTICAST |
 77			NDIS_PACKET_TYPE_DIRECTED);
 78}
 79
 80static void netvsc_set_multicast_list(struct net_device *net)
 81{
 82	struct net_device_context *net_device_ctx = netdev_priv(net);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 83
 84	schedule_work(&net_device_ctx->work);
 
 
 
 
 
 
 85}
 86
 87static int netvsc_open(struct net_device *net)
 88{
 89	struct net_device_context *net_device_ctx = netdev_priv(net);
 90	struct hv_device *device_obj = net_device_ctx->device_ctx;
 91	struct netvsc_device *nvdev;
 92	struct rndis_device *rdev;
 93	int ret = 0;
 94
 95	netif_carrier_off(net);
 96
 97	/* Open up the device */
 98	ret = rndis_filter_open(device_obj);
 99	if (ret != 0) {
100		netdev_err(net, "unable to open device (ret %d).\n", ret);
101		return ret;
102	}
103
104	netif_start_queue(net);
105
106	nvdev = hv_get_drvdata(device_obj);
107	rdev = nvdev->extension;
108	if (!rdev->link_state)
109		netif_carrier_on(net);
 
 
110
111	return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
112}
113
114static int netvsc_close(struct net_device *net)
115{
116	struct net_device_context *net_device_ctx = netdev_priv(net);
117	struct hv_device *device_obj = net_device_ctx->device_ctx;
 
 
118	int ret;
119
120	netif_tx_disable(net);
121
122	/* Make sure netvsc_set_multicast_list doesn't re-enable filter! */
123	cancel_work_sync(&net_device_ctx->work);
124	ret = rndis_filter_close(device_obj);
125	if (ret != 0)
 
 
126		netdev_err(net, "unable to close device (ret %d).\n", ret);
 
 
 
 
 
 
 
 
 
127
128	return ret;
129}
130
131static void *init_ppi_data(struct rndis_message *msg, u32 ppi_size,
132				int pkt_type)
133{
134	struct rndis_packet *rndis_pkt;
135	struct rndis_per_packet_info *ppi;
136
137	rndis_pkt = &msg->msg.pkt;
138	rndis_pkt->data_offset += ppi_size;
139
140	ppi = (struct rndis_per_packet_info *)((void *)rndis_pkt +
141		rndis_pkt->per_pkt_info_offset + rndis_pkt->per_pkt_info_len);
142
143	ppi->size = ppi_size;
144	ppi->type = pkt_type;
 
145	ppi->ppi_offset = sizeof(struct rndis_per_packet_info);
146
147	rndis_pkt->per_pkt_info_len += ppi_size;
148
149	return ppi;
150}
151
152static void netvsc_xmit_completion(void *context)
 
 
 
 
 
153{
154	struct hv_netvsc_packet *packet = (struct hv_netvsc_packet *)context;
155	struct sk_buff *skb = (struct sk_buff *)
156		(unsigned long)packet->completion.send.send_completion_tid;
 
 
157
158	kfree(packet);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
159
160	if (skb)
161		dev_kfree_skb_any(skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
162}
163
164static u32 fill_pg_buf(struct page *page, u32 offset, u32 len,
165			struct hv_page_buffer *pb)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
166{
167	int j = 0;
168
169	/* Deal with compund pages by ignoring unused part
170	 * of the page.
171	 */
172	page += (offset >> PAGE_SHIFT);
173	offset &= ~PAGE_MASK;
174
175	while (len > 0) {
176		unsigned long bytes;
177
178		bytes = PAGE_SIZE - offset;
179		if (bytes > len)
180			bytes = len;
181		pb[j].pfn = page_to_pfn(page);
182		pb[j].offset = offset;
183		pb[j].len = bytes;
184
185		offset += bytes;
186		len -= bytes;
187
188		if (offset == PAGE_SIZE && len) {
189			page++;
190			offset = 0;
191			j++;
192		}
193	}
194
195	return j + 1;
196}
197
198static u32 init_page_array(void *hdr, u32 len, struct sk_buff *skb,
 
199			   struct hv_page_buffer *pb)
200{
201	u32 slots_used = 0;
202	char *data = skb->data;
203	int frags = skb_shinfo(skb)->nr_frags;
204	int i;
205
206	/* The packet is laid out thus:
207	 * 1. hdr
208	 * 2. skb linear data
209	 * 3. skb fragment data
210	 */
211	if (hdr != NULL)
212		slots_used += fill_pg_buf(virt_to_page(hdr),
213					offset_in_page(hdr),
214					len, &pb[slots_used]);
215
216	slots_used += fill_pg_buf(virt_to_page(data),
217				offset_in_page(data),
218				skb_headlen(skb), &pb[slots_used]);
 
 
 
 
219
220	for (i = 0; i < frags; i++) {
221		skb_frag_t *frag = skb_shinfo(skb)->frags + i;
222
223		slots_used += fill_pg_buf(skb_frag_page(frag),
224					frag->page_offset,
225					skb_frag_size(frag), &pb[slots_used]);
 
226	}
227	return slots_used;
228}
229
230static int count_skb_frag_slots(struct sk_buff *skb)
231{
232	int i, frags = skb_shinfo(skb)->nr_frags;
233	int pages = 0;
234
235	for (i = 0; i < frags; i++) {
236		skb_frag_t *frag = skb_shinfo(skb)->frags + i;
237		unsigned long size = skb_frag_size(frag);
238		unsigned long offset = frag->page_offset;
239
240		/* Skip unused frames from start of page */
241		offset &= ~PAGE_MASK;
242		pages += PFN_UP(offset + size);
243	}
244	return pages;
245}
246
247static int netvsc_get_slots(struct sk_buff *skb)
248{
249	char *data = skb->data;
250	unsigned int offset = offset_in_page(data);
251	unsigned int len = skb_headlen(skb);
252	int slots;
253	int frag_slots;
254
255	slots = DIV_ROUND_UP(offset + len, PAGE_SIZE);
256	frag_slots = count_skb_frag_slots(skb);
257	return slots + frag_slots;
258}
259
260static u32 get_net_transport_info(struct sk_buff *skb, u32 *trans_off)
261{
262	u32 ret_val = TRANSPORT_INFO_NOT_IP;
 
 
 
 
 
 
 
 
263
264	if ((eth_hdr(skb)->h_proto != htons(ETH_P_IP)) &&
265		(eth_hdr(skb)->h_proto != htons(ETH_P_IPV6))) {
266		goto not_ip;
 
267	}
268
269	*trans_off = skb_transport_offset(skb);
 
 
 
 
 
 
 
 
 
270
271	if ((eth_hdr(skb)->h_proto == htons(ETH_P_IP))) {
272		struct iphdr *iphdr = ip_hdr(skb);
273
274		if (iphdr->protocol == IPPROTO_TCP)
275			ret_val = TRANSPORT_INFO_IPV4_TCP;
276		else if (iphdr->protocol == IPPROTO_UDP)
277			ret_val = TRANSPORT_INFO_IPV4_UDP;
 
 
 
 
 
278	} else {
279		if (ipv6_hdr(skb)->nexthdr == IPPROTO_TCP)
280			ret_val = TRANSPORT_INFO_IPV6_TCP;
281		else if (ipv6_hdr(skb)->nexthdr == IPPROTO_UDP)
282			ret_val = TRANSPORT_INFO_IPV6_UDP;
283	}
284
285not_ip:
286	return ret_val;
287}
288
289static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
290{
291	struct net_device_context *net_device_ctx = netdev_priv(net);
292	struct hv_netvsc_packet *packet;
293	int ret;
294	unsigned int num_data_pgs;
295	struct rndis_message *rndis_msg;
296	struct rndis_packet *rndis_pkt;
297	u32 rndis_msg_size;
298	bool isvlan;
299	struct rndis_per_packet_info *ppi;
300	struct ndis_tcp_ip_checksum_info *csum_info;
301	struct ndis_tcp_lso_info *lso_info;
302	int  hdr_offset;
303	u32 net_trans_info;
304
 
 
 
 
 
 
 
 
 
305
306	/* We will atmost need two pages to describe the rndis
307	 * header. We can only transmit MAX_PAGE_BUFFER_COUNT number
308	 * of pages in a single packet.
 
309	 */
 
310	num_data_pgs = netvsc_get_slots(skb) + 2;
311	if (num_data_pgs > MAX_PAGE_BUFFER_COUNT) {
312		netdev_err(net, "Packet too big: %u\n", skb->len);
313		dev_kfree_skb(skb);
314		net->stats.tx_dropped++;
315		return NETDEV_TX_OK;
316	}
317
318	/* Allocate a netvsc packet based on # of frags. */
319	packet = kzalloc(sizeof(struct hv_netvsc_packet) +
320			 (num_data_pgs * sizeof(struct hv_page_buffer)) +
321			 sizeof(struct rndis_message) +
322			 NDIS_VLAN_PPI_SIZE +
323			 NDIS_CSUM_PPI_SIZE +
324			 NDIS_LSO_PPI_SIZE, GFP_ATOMIC);
325	if (!packet) {
326		/* out of memory, drop packet */
327		netdev_err(net, "unable to allocate hv_netvsc_packet\n");
328
329		dev_kfree_skb(skb);
330		net->stats.tx_dropped++;
331		return NETDEV_TX_OK;
 
 
 
 
 
332	}
333
334	packet->vlan_tci = skb->vlan_tci;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
335
336	packet->is_data_pkt = true;
337	packet->total_data_buflen = skb->len;
 
 
338
339	packet->rndis_msg = (struct rndis_message *)((unsigned long)packet +
340				sizeof(struct hv_netvsc_packet) +
341				(num_data_pgs * sizeof(struct hv_page_buffer)));
342
343	/* Set the completion routine */
344	packet->completion.send.send_completion = netvsc_xmit_completion;
345	packet->completion.send.send_completion_ctx = packet;
346	packet->completion.send.send_completion_tid = (unsigned long)skb;
347
348	isvlan = packet->vlan_tci & VLAN_TAG_PRESENT;
349
350	/* Add the rndis header */
351	rndis_msg = packet->rndis_msg;
352	rndis_msg->ndis_msg_type = RNDIS_MSG_PACKET;
353	rndis_msg->msg_len = packet->total_data_buflen;
354	rndis_pkt = &rndis_msg->msg.pkt;
355	rndis_pkt->data_offset = sizeof(struct rndis_packet);
356	rndis_pkt->data_len = packet->total_data_buflen;
357	rndis_pkt->per_pkt_info_offset = sizeof(struct rndis_packet);
358
359	rndis_msg_size = RNDIS_MESSAGE_SIZE(struct rndis_packet);
 
 
 
 
360
361	if (isvlan) {
362		struct ndis_pkt_8021q_info *vlan;
363
364		rndis_msg_size += NDIS_VLAN_PPI_SIZE;
365		ppi = init_ppi_data(rndis_msg, NDIS_VLAN_PPI_SIZE,
366					IEEE_8021Q_INFO);
367		vlan = (struct ndis_pkt_8021q_info *)((void *)ppi +
368						ppi->ppi_offset);
369		vlan->vlanid = packet->vlan_tci & VLAN_VID_MASK;
370		vlan->pri = (packet->vlan_tci & VLAN_PRIO_MASK) >>
371				VLAN_PRIO_SHIFT;
372	}
373
374	net_trans_info = get_net_transport_info(skb, &hdr_offset);
375	if (net_trans_info == TRANSPORT_INFO_NOT_IP)
376		goto do_send;
377
378	/*
379	 * Setup the sendside checksum offload only if this is not a
380	 * GSO packet.
381	 */
382	if (skb_is_gso(skb))
383		goto do_lso;
384
385	if ((skb->ip_summed == CHECKSUM_NONE) ||
386	    (skb->ip_summed == CHECKSUM_UNNECESSARY))
387		goto do_send;
388
389	rndis_msg_size += NDIS_CSUM_PPI_SIZE;
390	ppi = init_ppi_data(rndis_msg, NDIS_CSUM_PPI_SIZE,
391			    TCPIP_CHKSUM_PKTINFO);
392
393	csum_info = (struct ndis_tcp_ip_checksum_info *)((void *)ppi +
394			ppi->ppi_offset);
395
396	if (net_trans_info & (INFO_IPV4 << 16))
397		csum_info->transmit.is_ipv4 = 1;
398	else
399		csum_info->transmit.is_ipv6 = 1;
 
 
 
 
400
401	if (net_trans_info & INFO_TCP) {
402		csum_info->transmit.tcp_checksum = 1;
403		csum_info->transmit.tcp_header_offset = hdr_offset;
404	} else if (net_trans_info & INFO_UDP) {
405		/* UDP checksum offload is not supported on ws2008r2.
406		 * Furthermore, on ws2012 and ws2012r2, there are some
407		 * issues with udp checksum offload from Linux guests.
408		 * (these are host issues).
409		 * For now compute the checksum here.
410		 */
411		struct udphdr *uh;
412		u16 udp_len;
413
414		ret = skb_cow_head(skb, 0);
415		if (ret)
416			goto drop;
417
418		uh = udp_hdr(skb);
419		udp_len = ntohs(uh->len);
420		uh->check = 0;
421		uh->check = csum_tcpudp_magic(ip_hdr(skb)->saddr,
422					      ip_hdr(skb)->daddr,
423					      udp_len, IPPROTO_UDP,
424					      csum_partial(uh, udp_len, 0));
425		if (uh->check == 0)
426			uh->check = CSUM_MANGLED_0;
427
428		csum_info->transmit.udp_checksum = 0;
429	}
430	goto do_send;
431
432do_lso:
433	rndis_msg_size += NDIS_LSO_PPI_SIZE;
434	ppi = init_ppi_data(rndis_msg, NDIS_LSO_PPI_SIZE,
435			    TCP_LARGESEND_PKTINFO);
436
437	lso_info = (struct ndis_tcp_lso_info *)((void *)ppi +
438			ppi->ppi_offset);
439
440	lso_info->lso_v2_transmit.type = NDIS_TCP_LARGE_SEND_OFFLOAD_V2_TYPE;
441	if (net_trans_info & (INFO_IPV4 << 16)) {
442		lso_info->lso_v2_transmit.ip_version =
443			NDIS_TCP_LARGE_SEND_OFFLOAD_IPV4;
444		ip_hdr(skb)->tot_len = 0;
445		ip_hdr(skb)->check = 0;
446		tcp_hdr(skb)->check =
447		~csum_tcpudp_magic(ip_hdr(skb)->saddr,
448				   ip_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
449	} else {
450		lso_info->lso_v2_transmit.ip_version =
451			NDIS_TCP_LARGE_SEND_OFFLOAD_IPV6;
452		ipv6_hdr(skb)->payload_len = 0;
453		tcp_hdr(skb)->check =
454		~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
455				&ipv6_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
456	}
457	lso_info->lso_v2_transmit.tcp_header_offset = hdr_offset;
458	lso_info->lso_v2_transmit.mss = skb_shinfo(skb)->gso_size;
459
460do_send:
461	/* Start filling in the page buffers with the rndis hdr */
462	rndis_msg->msg_len += rndis_msg_size;
 
463	packet->page_buf_cnt = init_page_array(rndis_msg, rndis_msg_size,
464					skb, &packet->page_buf[0]);
465
466	ret = netvsc_send(net_device_ctx->device_ctx, packet);
 
467
468drop:
469	if (ret == 0) {
470		net->stats.tx_bytes += skb->len;
471		net->stats.tx_packets++;
472	} else {
473		kfree(packet);
474		if (ret != -EAGAIN) {
475			dev_kfree_skb_any(skb);
476			net->stats.tx_dropped++;
477		}
478	}
479
480	return (ret == -EAGAIN) ? NETDEV_TX_BUSY : NETDEV_TX_OK;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
481}
482
483/*
484 * netvsc_linkstatus_callback - Link up/down notification
485 */
486void netvsc_linkstatus_callback(struct hv_device *device_obj,
487				       unsigned int status)
488{
489	struct net_device *net;
490	struct net_device_context *ndev_ctx;
491	struct netvsc_device *net_device;
492	struct rndis_device *rdev;
 
 
 
 
 
 
 
 
493
494	net_device = hv_get_drvdata(device_obj);
495	rdev = net_device->extension;
496
497	rdev->link_state = status != 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
498
499	net = net_device->ndev;
 
 
 
500
501	if (!net || net->reg_state != NETREG_REGISTERED)
 
 
 
502		return;
503
504	ndev_ctx = netdev_priv(net);
505	if (status == 1) {
506		schedule_delayed_work(&ndev_ctx->dwork, 0);
507		schedule_delayed_work(&ndev_ctx->dwork, msecs_to_jiffies(20));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
508	} else {
509		schedule_delayed_work(&ndev_ctx->dwork, 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
510	}
 
 
 
 
 
 
 
 
 
 
 
 
 
511}
512
513/*
514 * netvsc_recv_callback -  Callback when we receive a packet from the
515 * "wire" on the specified device.
516 */
517int netvsc_recv_callback(struct hv_device *device_obj,
518				struct hv_netvsc_packet *packet,
519				struct ndis_tcp_ip_checksum_info *csum_info)
520{
521	struct net_device *net;
 
 
522	struct sk_buff *skb;
 
 
 
523
524	net = ((struct netvsc_device *)hv_get_drvdata(device_obj))->ndev;
525	if (!net || net->reg_state != NETREG_REGISTERED) {
526		packet->status = NVSP_STAT_FAIL;
527		return 0;
 
 
 
 
 
 
 
528	}
529
530	/* Allocate a skb - TODO direct I/O to pages? */
531	skb = netdev_alloc_skb_ip_align(net, packet->total_data_buflen);
 
532	if (unlikely(!skb)) {
533		++net->stats.rx_dropped;
534		packet->status = NVSP_STAT_FAIL;
535		return 0;
536	}
537
 
 
538	/*
539	 * Copy to skb. This copy is needed here since the memory pointed by
540	 * hv_netvsc_packet cannot be deallocated
 
541	 */
542	memcpy(skb_put(skb, packet->total_data_buflen), packet->data,
543		packet->total_data_buflen);
 
 
 
 
 
 
 
 
 
 
 
 
544
545	skb->protocol = eth_type_trans(skb, net);
546	if (csum_info) {
547		/* We only look at the IP checksum here.
548		 * Should we be dropping the packet if checksum
549		 * failed? How do we deal with other checksums - TCP/UDP?
550		 */
551		if (csum_info->receive.ip_checksum_succeeded)
552			skb->ip_summed = CHECKSUM_UNNECESSARY;
553		else
554			skb->ip_summed = CHECKSUM_NONE;
 
 
 
 
 
 
 
 
 
 
555	}
 
556
557	if (packet->vlan_tci & VLAN_TAG_PRESENT)
558		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
559				       packet->vlan_tci);
 
 
 
 
 
560
561	net->stats.rx_packets++;
562	net->stats.rx_bytes += packet->total_data_buflen;
563
564	/*
565	 * Pass the skb back up. Network stack will deallocate the skb when it
566	 * is done.
567	 * TODO - use NAPI?
568	 */
569	netif_rx(skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
570
571	return 0;
572}
573
574static void netvsc_get_drvinfo(struct net_device *net,
575			       struct ethtool_drvinfo *info)
576{
577	strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
578	strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
579}
580
581static int netvsc_change_mtu(struct net_device *ndev, int mtu)
582{
583	struct net_device_context *ndevctx = netdev_priv(ndev);
584	struct hv_device *hdev =  ndevctx->device_ctx;
585	struct netvsc_device *nvdev = hv_get_drvdata(hdev);
586	struct netvsc_device_info device_info;
587	int limit = ETH_DATA_LEN;
 
588
589	if (nvdev == NULL || nvdev->destroy)
590		return -ENODEV;
591
592	if (nvdev->nvsp_version >= NVSP_PROTOCOL_VERSION_2)
593		limit = NETVSC_MTU;
594
595	if (mtu < 68 || mtu > limit)
596		return -EINVAL;
597
598	nvdev->start_remove = true;
599	cancel_work_sync(&ndevctx->work);
600	netif_tx_disable(ndev);
601	rndis_filter_device_remove(hdev);
 
 
 
 
 
 
602
603	ndev->mtu = mtu;
604
605	ndevctx->device_ctx = hdev;
606	hv_set_drvdata(hdev, ndev);
607	device_info.ring_size = ring_size;
608	rndis_filter_device_add(hdev, &device_info);
609	netif_wake_queue(ndev);
 
 
 
 
 
 
 
610
611	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
612}
613
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
614
615static int netvsc_set_mac_addr(struct net_device *ndev, void *p)
616{
617	struct net_device_context *ndevctx = netdev_priv(ndev);
618	struct hv_device *hdev =  ndevctx->device_ctx;
 
619	struct sockaddr *addr = p;
620	char save_adr[ETH_ALEN];
621	unsigned char save_aatype;
622	int err;
623
624	memcpy(save_adr, ndev->dev_addr, ETH_ALEN);
625	save_aatype = ndev->addr_assign_type;
626
627	err = eth_mac_addr(ndev, p);
628	if (err != 0)
629		return err;
630
631	err = rndis_filter_set_device_mac(hdev, addr->sa_data);
632	if (err != 0) {
633		/* roll back to saved MAC */
634		memcpy(ndev->dev_addr, save_adr, ETH_ALEN);
635		ndev->addr_assign_type = save_aatype;
 
 
 
 
 
 
 
 
 
 
 
636	}
637
638	return err;
639}
640
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
641
642static const struct ethtool_ops ethtool_ops = {
643	.get_drvinfo	= netvsc_get_drvinfo,
 
 
 
 
644	.get_link	= ethtool_op_get_link,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
645};
646
647static const struct net_device_ops device_ops = {
648	.ndo_open =			netvsc_open,
649	.ndo_stop =			netvsc_close,
650	.ndo_start_xmit =		netvsc_start_xmit,
651	.ndo_set_rx_mode =		netvsc_set_multicast_list,
 
 
 
652	.ndo_change_mtu =		netvsc_change_mtu,
653	.ndo_validate_addr =		eth_validate_addr,
654	.ndo_set_mac_address =		netvsc_set_mac_addr,
 
 
 
655};
656
657/*
658 * Send GARP packet to network peers after migrations.
659 * After Quick Migration, the network is not immediately operational in the
660 * current context when receiving RNDIS_STATUS_MEDIA_CONNECT event. So, add
661 * another netif_notify_peers() into a delayed work, otherwise GARP packet
662 * will not be sent after quick migration, and cause network disconnection.
663 * Also, we update the carrier status here.
664 */
665static void netvsc_link_change(struct work_struct *w)
666{
667	struct net_device_context *ndev_ctx;
668	struct net_device *net;
 
 
 
 
669	struct netvsc_device *net_device;
670	struct rndis_device *rdev;
671	bool notify;
672
673	rtnl_lock();
 
 
 
 
 
 
 
 
674
675	ndev_ctx = container_of(w, struct net_device_context, dwork.work);
676	net_device = hv_get_drvdata(ndev_ctx->device_ctx);
677	rdev = net_device->extension;
678	net = net_device->ndev;
679
680	if (rdev->link_state) {
681		netif_carrier_off(net);
682		notify = false;
683	} else {
684		netif_carrier_on(net);
685		notify = true;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
686	}
687
688	rtnl_unlock();
689
690	if (notify)
691		netdev_notify_peers(net);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
692}
693
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
694
695static int netvsc_probe(struct hv_device *dev,
696			const struct hv_vmbus_device_id *dev_id)
697{
698	struct net_device *net = NULL;
699	struct net_device_context *net_device_ctx;
700	struct netvsc_device_info device_info;
701	int ret;
 
702
703	net = alloc_etherdev(sizeof(struct net_device_context));
 
704	if (!net)
705		return -ENOMEM;
706
707	netif_carrier_off(net);
708
 
 
709	net_device_ctx = netdev_priv(net);
710	net_device_ctx->device_ctx = dev;
 
 
 
 
 
711	hv_set_drvdata(dev, net);
 
712	INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_link_change);
713	INIT_WORK(&net_device_ctx->work, do_set_multicast);
 
 
 
 
 
 
 
 
714
715	net->netdev_ops = &device_ops;
 
 
716
717	net->hw_features = NETIF_F_RXCSUM | NETIF_F_SG | NETIF_F_IP_CSUM |
718				NETIF_F_TSO;
719	net->features = NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_SG | NETIF_F_RXCSUM |
720			NETIF_F_IP_CSUM | NETIF_F_TSO;
721
722	SET_ETHTOOL_OPS(net, &ethtool_ops);
723	SET_NETDEV_DEV(net, &dev->device);
 
 
 
724
725	/* Notify the netvsc driver of the new device */
726	device_info.ring_size = ring_size;
727	ret = rndis_filter_device_add(dev, &device_info);
728	if (ret != 0) {
 
 
 
 
 
 
 
729		netdev_err(net, "unable to add netvsc device (ret %d)\n", ret);
730		free_netdev(net);
731		hv_set_drvdata(dev, NULL);
732		return ret;
733	}
734	memcpy(net->dev_addr, device_info.mac_adr, ETH_ALEN);
735
736	ret = register_netdev(net);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
737	if (ret != 0) {
738		pr_err("Unable to register netdev.\n");
739		rndis_filter_device_remove(dev);
740		free_netdev(net);
741	} else {
742		schedule_delayed_work(&net_device_ctx->dwork, 0);
743	}
744
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
745	return ret;
746}
747
748static int netvsc_remove(struct hv_device *dev)
749{
750	struct net_device *net;
751	struct net_device_context *ndev_ctx;
752	struct netvsc_device *net_device;
753
754	net_device = hv_get_drvdata(dev);
755	net = net_device->ndev;
756
 
757	if (net == NULL) {
758		dev_err(&dev->device, "No net device to remove\n");
759		return 0;
760	}
761
762	net_device->start_remove = true;
763
764	ndev_ctx = netdev_priv(net);
765	cancel_delayed_work_sync(&ndev_ctx->dwork);
766	cancel_work_sync(&ndev_ctx->work);
767
768	/* Stop outbound asap */
769	netif_tx_disable(net);
770
771	unregister_netdev(net);
 
 
 
 
 
772
773	/*
774	 * Call to the vsc driver to let it know that the device is being
775	 * removed
776	 */
777	rndis_filter_device_remove(dev);
 
 
 
 
 
 
 
 
778
 
 
 
 
 
779	free_netdev(net);
780	return 0;
781}
782
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
783static const struct hv_vmbus_device_id id_table[] = {
784	/* Network guid */
785	{ HV_NIC_GUID, },
786	{ },
787};
788
789MODULE_DEVICE_TABLE(vmbus, id_table);
790
791/* The one and only one */
792static struct  hv_driver netvsc_drv = {
793	.name = KBUILD_MODNAME,
794	.id_table = id_table,
795	.probe = netvsc_probe,
796	.remove = netvsc_remove,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
797};
798
799static void __exit netvsc_drv_exit(void)
800{
 
801	vmbus_driver_unregister(&netvsc_drv);
802}
803
804static int __init netvsc_drv_init(void)
805{
 
 
806	if (ring_size < RING_SIZE_MIN) {
807		ring_size = RING_SIZE_MIN;
808		pr_info("Increased ring_size to %d (min allowed)\n",
809			ring_size);
810	}
811	return vmbus_driver_register(&netvsc_drv);
 
 
 
 
 
 
 
812}
813
814MODULE_LICENSE("GPL");
815MODULE_DESCRIPTION("Microsoft Hyper-V network driver");
816
817module_init(netvsc_drv_init);
818module_exit(netvsc_drv_exit);
v5.14.15
   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
  45static unsigned int ring_size __ro_after_init = 128;
  46module_param(ring_size, uint, 0444);
 
  47MODULE_PARM_DESC(ring_size, "Ring buffer size (# of pages)");
  48unsigned int netvsc_ring_bytes __ro_after_init;
  49
  50static const u32 default_msg = NETIF_MSG_DRV | NETIF_MSG_PROBE |
  51				NETIF_MSG_LINK | NETIF_MSG_IFUP |
  52				NETIF_MSG_IFDOWN | NETIF_MSG_RX_ERR |
  53				NETIF_MSG_TX_ERR;
  54
  55static int debug = -1;
  56module_param(debug, int, 0444);
  57MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
  58
  59static LIST_HEAD(netvsc_dev_list);
  60
  61static void netvsc_change_rx_flags(struct net_device *net, int change)
  62{
  63	struct net_device_context *ndev_ctx = netdev_priv(net);
  64	struct net_device *vf_netdev = rtnl_dereference(ndev_ctx->vf_netdev);
  65	int inc;
 
  66
  67	if (!vf_netdev)
 
  68		return;
  69
  70	if (change & IFF_PROMISC) {
  71		inc = (net->flags & IFF_PROMISC) ? 1 : -1;
  72		dev_set_promiscuity(vf_netdev, inc);
  73	}
  74
  75	if (change & IFF_ALLMULTI) {
  76		inc = (net->flags & IFF_ALLMULTI) ? 1 : -1;
  77		dev_set_allmulti(vf_netdev, inc);
  78	}
 
 
 
 
  79}
  80
  81static void netvsc_set_rx_mode(struct net_device *net)
  82{
  83	struct net_device_context *ndev_ctx = netdev_priv(net);
  84	struct net_device *vf_netdev;
  85	struct netvsc_device *nvdev;
  86
  87	rcu_read_lock();
  88	vf_netdev = rcu_dereference(ndev_ctx->vf_netdev);
  89	if (vf_netdev) {
  90		dev_uc_sync(vf_netdev, net);
  91		dev_mc_sync(vf_netdev, net);
  92	}
  93
  94	nvdev = rcu_dereference(ndev_ctx->nvdev);
  95	if (nvdev)
  96		rndis_filter_update(nvdev);
  97	rcu_read_unlock();
  98}
  99
 100static void netvsc_tx_enable(struct netvsc_device *nvscdev,
 101			     struct net_device *ndev)
 102{
 103	nvscdev->tx_disable = false;
 104	virt_wmb(); /* ensure queue wake up mechanism is on */
 105
 106	netif_tx_wake_all_queues(ndev);
 107}
 108
 109static int netvsc_open(struct net_device *net)
 110{
 111	struct net_device_context *ndev_ctx = netdev_priv(net);
 112	struct net_device *vf_netdev = rtnl_dereference(ndev_ctx->vf_netdev);
 113	struct netvsc_device *nvdev = rtnl_dereference(ndev_ctx->nvdev);
 114	struct rndis_device *rdev;
 115	int ret = 0;
 116
 117	netif_carrier_off(net);
 118
 119	/* Open up the device */
 120	ret = rndis_filter_open(nvdev);
 121	if (ret != 0) {
 122		netdev_err(net, "unable to open device (ret %d).\n", ret);
 123		return ret;
 124	}
 125
 
 
 
 126	rdev = nvdev->extension;
 127	if (!rdev->link_state) {
 128		netif_carrier_on(net);
 129		netvsc_tx_enable(nvdev, net);
 130	}
 131
 132	if (vf_netdev) {
 133		/* Setting synthetic device up transparently sets
 134		 * slave as up. If open fails, then slave will be
 135		 * still be offline (and not used).
 136		 */
 137		ret = dev_open(vf_netdev, NULL);
 138		if (ret)
 139			netdev_warn(net,
 140				    "unable to open slave: %s: %d\n",
 141				    vf_netdev->name, ret);
 142	}
 143	return 0;
 144}
 145
 146static int netvsc_wait_until_empty(struct netvsc_device *nvdev)
 147{
 148	unsigned int retry = 0;
 149	int i;
 150
 151	/* Ensure pending bytes in ring are read */
 152	for (;;) {
 153		u32 aread = 0;
 154
 155		for (i = 0; i < nvdev->num_chn; i++) {
 156			struct vmbus_channel *chn
 157				= nvdev->chan_table[i].channel;
 158
 159			if (!chn)
 160				continue;
 161
 162			/* make sure receive not running now */
 163			napi_synchronize(&nvdev->chan_table[i].napi);
 164
 165			aread = hv_get_bytes_to_read(&chn->inbound);
 166			if (aread)
 167				break;
 168
 169			aread = hv_get_bytes_to_read(&chn->outbound);
 170			if (aread)
 171				break;
 172		}
 173
 174		if (aread == 0)
 175			return 0;
 176
 177		if (++retry > RETRY_MAX)
 178			return -ETIMEDOUT;
 179
 180		usleep_range(RETRY_US_LO, RETRY_US_HI);
 181	}
 182}
 183
 184static void netvsc_tx_disable(struct netvsc_device *nvscdev,
 185			      struct net_device *ndev)
 186{
 187	if (nvscdev) {
 188		nvscdev->tx_disable = true;
 189		virt_wmb(); /* ensure txq will not wake up after stop */
 190	}
 191
 192	netif_tx_disable(ndev);
 193}
 194
 195static int netvsc_close(struct net_device *net)
 196{
 197	struct net_device_context *net_device_ctx = netdev_priv(net);
 198	struct net_device *vf_netdev
 199		= rtnl_dereference(net_device_ctx->vf_netdev);
 200	struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
 201	int ret;
 202
 203	netvsc_tx_disable(nvdev, net);
 204
 205	/* No need to close rndis filter if it is removed already */
 206	if (!nvdev)
 207		return 0;
 208
 209	ret = rndis_filter_close(nvdev);
 210	if (ret != 0) {
 211		netdev_err(net, "unable to close device (ret %d).\n", ret);
 212		return ret;
 213	}
 214
 215	ret = netvsc_wait_until_empty(nvdev);
 216	if (ret)
 217		netdev_err(net, "Ring buffer not empty after closing rndis\n");
 218
 219	if (vf_netdev)
 220		dev_close(vf_netdev);
 221
 222	return ret;
 223}
 224
 225static inline void *init_ppi_data(struct rndis_message *msg,
 226				  u32 ppi_size, u32 pkt_type)
 227{
 228	struct rndis_packet *rndis_pkt = &msg->msg.pkt;
 229	struct rndis_per_packet_info *ppi;
 230
 
 231	rndis_pkt->data_offset += ppi_size;
 232	ppi = (void *)rndis_pkt + rndis_pkt->per_pkt_info_offset
 233		+ rndis_pkt->per_pkt_info_len;
 
 234
 235	ppi->size = ppi_size;
 236	ppi->type = pkt_type;
 237	ppi->internal = 0;
 238	ppi->ppi_offset = sizeof(struct rndis_per_packet_info);
 239
 240	rndis_pkt->per_pkt_info_len += ppi_size;
 241
 242	return ppi + 1;
 243}
 244
 245/* Azure hosts don't support non-TCP port numbers in hashing for fragmented
 246 * packets. We can use ethtool to change UDP hash level when necessary.
 247 */
 248static inline u32 netvsc_get_hash(
 249	struct sk_buff *skb,
 250	const struct net_device_context *ndc)
 251{
 252	struct flow_keys flow;
 253	u32 hash, pkt_proto = 0;
 254	static u32 hashrnd __read_mostly;
 255
 256	net_get_random_once(&hashrnd, sizeof(hashrnd));
 257
 258	if (!skb_flow_dissect_flow_keys(skb, &flow, 0))
 259		return 0;
 260
 261	switch (flow.basic.ip_proto) {
 262	case IPPROTO_TCP:
 263		if (flow.basic.n_proto == htons(ETH_P_IP))
 264			pkt_proto = HV_TCP4_L4HASH;
 265		else if (flow.basic.n_proto == htons(ETH_P_IPV6))
 266			pkt_proto = HV_TCP6_L4HASH;
 267
 268		break;
 269
 270	case IPPROTO_UDP:
 271		if (flow.basic.n_proto == htons(ETH_P_IP))
 272			pkt_proto = HV_UDP4_L4HASH;
 273		else if (flow.basic.n_proto == htons(ETH_P_IPV6))
 274			pkt_proto = HV_UDP6_L4HASH;
 275
 276		break;
 277	}
 278
 279	if (pkt_proto & ndc->l4_hash) {
 280		return skb_get_hash(skb);
 281	} else {
 282		if (flow.basic.n_proto == htons(ETH_P_IP))
 283			hash = jhash2((u32 *)&flow.addrs.v4addrs, 2, hashrnd);
 284		else if (flow.basic.n_proto == htons(ETH_P_IPV6))
 285			hash = jhash2((u32 *)&flow.addrs.v6addrs, 8, hashrnd);
 286		else
 287			return 0;
 288
 289		__skb_set_sw_hash(skb, hash, false);
 290	}
 291
 292	return hash;
 293}
 294
 295static inline int netvsc_get_tx_queue(struct net_device *ndev,
 296				      struct sk_buff *skb, int old_idx)
 297{
 298	const struct net_device_context *ndc = netdev_priv(ndev);
 299	struct sock *sk = skb->sk;
 300	int q_idx;
 301
 302	q_idx = ndc->tx_table[netvsc_get_hash(skb, ndc) &
 303			      (VRSS_SEND_TAB_SIZE - 1)];
 304
 305	/* If queue index changed record the new value */
 306	if (q_idx != old_idx &&
 307	    sk && sk_fullsock(sk) && rcu_access_pointer(sk->sk_dst_cache))
 308		sk_tx_queue_set(sk, q_idx);
 309
 310	return q_idx;
 311}
 312
 313/*
 314 * Select queue for transmit.
 315 *
 316 * If a valid queue has already been assigned, then use that.
 317 * Otherwise compute tx queue based on hash and the send table.
 318 *
 319 * This is basically similar to default (netdev_pick_tx) with the added step
 320 * of using the host send_table when no other queue has been assigned.
 321 *
 322 * TODO support XPS - but get_xps_queue not exported
 323 */
 324static u16 netvsc_pick_tx(struct net_device *ndev, struct sk_buff *skb)
 325{
 326	int q_idx = sk_tx_queue_get(skb->sk);
 327
 328	if (q_idx < 0 || skb->ooo_okay || q_idx >= ndev->real_num_tx_queues) {
 329		/* If forwarding a packet, we use the recorded queue when
 330		 * available for better cache locality.
 331		 */
 332		if (skb_rx_queue_recorded(skb))
 333			q_idx = skb_get_rx_queue(skb);
 334		else
 335			q_idx = netvsc_get_tx_queue(ndev, skb, q_idx);
 336	}
 337
 338	return q_idx;
 339}
 340
 341static u16 netvsc_select_queue(struct net_device *ndev, struct sk_buff *skb,
 342			       struct net_device *sb_dev)
 343{
 344	struct net_device_context *ndc = netdev_priv(ndev);
 345	struct net_device *vf_netdev;
 346	u16 txq;
 347
 348	rcu_read_lock();
 349	vf_netdev = rcu_dereference(ndc->vf_netdev);
 350	if (vf_netdev) {
 351		const struct net_device_ops *vf_ops = vf_netdev->netdev_ops;
 352
 353		if (vf_ops->ndo_select_queue)
 354			txq = vf_ops->ndo_select_queue(vf_netdev, skb, sb_dev);
 355		else
 356			txq = netdev_pick_tx(vf_netdev, skb, NULL);
 357
 358		/* Record the queue selected by VF so that it can be
 359		 * used for common case where VF has more queues than
 360		 * the synthetic device.
 361		 */
 362		qdisc_skb_cb(skb)->slave_dev_queue_mapping = txq;
 363	} else {
 364		txq = netvsc_pick_tx(ndev, skb);
 365	}
 366	rcu_read_unlock();
 367
 368	while (txq >= ndev->real_num_tx_queues)
 369		txq -= ndev->real_num_tx_queues;
 370
 371	return txq;
 372}
 373
 374static u32 fill_pg_buf(unsigned long hvpfn, u32 offset, u32 len,
 375		       struct hv_page_buffer *pb)
 376{
 377	int j = 0;
 378
 379	hvpfn += offset >> HV_HYP_PAGE_SHIFT;
 380	offset = offset & ~HV_HYP_PAGE_MASK;
 
 
 
 381
 382	while (len > 0) {
 383		unsigned long bytes;
 384
 385		bytes = HV_HYP_PAGE_SIZE - offset;
 386		if (bytes > len)
 387			bytes = len;
 388		pb[j].pfn = hvpfn;
 389		pb[j].offset = offset;
 390		pb[j].len = bytes;
 391
 392		offset += bytes;
 393		len -= bytes;
 394
 395		if (offset == HV_HYP_PAGE_SIZE && len) {
 396			hvpfn++;
 397			offset = 0;
 398			j++;
 399		}
 400	}
 401
 402	return j + 1;
 403}
 404
 405static u32 init_page_array(void *hdr, u32 len, struct sk_buff *skb,
 406			   struct hv_netvsc_packet *packet,
 407			   struct hv_page_buffer *pb)
 408{
 409	u32 slots_used = 0;
 410	char *data = skb->data;
 411	int frags = skb_shinfo(skb)->nr_frags;
 412	int i;
 413
 414	/* The packet is laid out thus:
 415	 * 1. hdr: RNDIS header and PPI
 416	 * 2. skb linear data
 417	 * 3. skb fragment data
 418	 */
 419	slots_used += fill_pg_buf(virt_to_hvpfn(hdr),
 420				  offset_in_hvpage(hdr),
 421				  len,
 422				  &pb[slots_used]);
 423
 424	packet->rmsg_size = len;
 425	packet->rmsg_pgcnt = slots_used;
 426
 427	slots_used += fill_pg_buf(virt_to_hvpfn(data),
 428				  offset_in_hvpage(data),
 429				  skb_headlen(skb),
 430				  &pb[slots_used]);
 431
 432	for (i = 0; i < frags; i++) {
 433		skb_frag_t *frag = skb_shinfo(skb)->frags + i;
 434
 435		slots_used += fill_pg_buf(page_to_hvpfn(skb_frag_page(frag)),
 436					  skb_frag_off(frag),
 437					  skb_frag_size(frag),
 438					  &pb[slots_used]);
 439	}
 440	return slots_used;
 441}
 442
 443static int count_skb_frag_slots(struct sk_buff *skb)
 444{
 445	int i, frags = skb_shinfo(skb)->nr_frags;
 446	int pages = 0;
 447
 448	for (i = 0; i < frags; i++) {
 449		skb_frag_t *frag = skb_shinfo(skb)->frags + i;
 450		unsigned long size = skb_frag_size(frag);
 451		unsigned long offset = skb_frag_off(frag);
 452
 453		/* Skip unused frames from start of page */
 454		offset &= ~HV_HYP_PAGE_MASK;
 455		pages += HVPFN_UP(offset + size);
 456	}
 457	return pages;
 458}
 459
 460static int netvsc_get_slots(struct sk_buff *skb)
 461{
 462	char *data = skb->data;
 463	unsigned int offset = offset_in_hvpage(data);
 464	unsigned int len = skb_headlen(skb);
 465	int slots;
 466	int frag_slots;
 467
 468	slots = DIV_ROUND_UP(offset + len, HV_HYP_PAGE_SIZE);
 469	frag_slots = count_skb_frag_slots(skb);
 470	return slots + frag_slots;
 471}
 472
 473static u32 net_checksum_info(struct sk_buff *skb)
 474{
 475	if (skb->protocol == htons(ETH_P_IP)) {
 476		struct iphdr *ip = ip_hdr(skb);
 477
 478		if (ip->protocol == IPPROTO_TCP)
 479			return TRANSPORT_INFO_IPV4_TCP;
 480		else if (ip->protocol == IPPROTO_UDP)
 481			return TRANSPORT_INFO_IPV4_UDP;
 482	} else {
 483		struct ipv6hdr *ip6 = ipv6_hdr(skb);
 484
 485		if (ip6->nexthdr == IPPROTO_TCP)
 486			return TRANSPORT_INFO_IPV6_TCP;
 487		else if (ip6->nexthdr == IPPROTO_UDP)
 488			return TRANSPORT_INFO_IPV6_UDP;
 489	}
 490
 491	return TRANSPORT_INFO_NOT_IP;
 492}
 493
 494/* Send skb on the slave VF device. */
 495static int netvsc_vf_xmit(struct net_device *net, struct net_device *vf_netdev,
 496			  struct sk_buff *skb)
 497{
 498	struct net_device_context *ndev_ctx = netdev_priv(net);
 499	unsigned int len = skb->len;
 500	int rc;
 501
 502	skb->dev = vf_netdev;
 503	skb_record_rx_queue(skb, qdisc_skb_cb(skb)->slave_dev_queue_mapping);
 504
 505	rc = dev_queue_xmit(skb);
 506	if (likely(rc == NET_XMIT_SUCCESS || rc == NET_XMIT_CN)) {
 507		struct netvsc_vf_pcpu_stats *pcpu_stats
 508			= this_cpu_ptr(ndev_ctx->vf_stats);
 509
 510		u64_stats_update_begin(&pcpu_stats->syncp);
 511		pcpu_stats->tx_packets++;
 512		pcpu_stats->tx_bytes += len;
 513		u64_stats_update_end(&pcpu_stats->syncp);
 514	} else {
 515		this_cpu_inc(ndev_ctx->vf_stats->tx_dropped);
 
 
 
 516	}
 517
 518	return rc;
 
 519}
 520
 521static int netvsc_xmit(struct sk_buff *skb, struct net_device *net, bool xdp_tx)
 522{
 523	struct net_device_context *net_device_ctx = netdev_priv(net);
 524	struct hv_netvsc_packet *packet = NULL;
 525	int ret;
 526	unsigned int num_data_pgs;
 527	struct rndis_message *rndis_msg;
 528	struct net_device *vf_netdev;
 529	u32 rndis_msg_size;
 530	u32 hash;
 531	struct hv_page_buffer pb[MAX_PAGE_BUFFER_COUNT];
 
 
 
 
 532
 533	/* If VF is present and up then redirect packets to it.
 534	 * Skip the VF if it is marked down or has no carrier.
 535	 * If netpoll is in uses, then VF can not be used either.
 536	 */
 537	vf_netdev = rcu_dereference_bh(net_device_ctx->vf_netdev);
 538	if (vf_netdev && netif_running(vf_netdev) &&
 539	    netif_carrier_ok(vf_netdev) && !netpoll_tx_running(net) &&
 540	    net_device_ctx->data_path_is_vf)
 541		return netvsc_vf_xmit(net, vf_netdev, skb);
 542
 543	/* We will atmost need two pages to describe the rndis
 544	 * header. We can only transmit MAX_PAGE_BUFFER_COUNT number
 545	 * of pages in a single packet. If skb is scattered around
 546	 * more pages we try linearizing it.
 547	 */
 548
 549	num_data_pgs = netvsc_get_slots(skb) + 2;
 
 
 
 
 
 
 550
 551	if (unlikely(num_data_pgs > MAX_PAGE_BUFFER_COUNT)) {
 552		++net_device_ctx->eth_stats.tx_scattered;
 
 
 
 
 
 
 
 
 553
 554		if (skb_linearize(skb))
 555			goto no_memory;
 556
 557		num_data_pgs = netvsc_get_slots(skb) + 2;
 558		if (num_data_pgs > MAX_PAGE_BUFFER_COUNT) {
 559			++net_device_ctx->eth_stats.tx_too_big;
 560			goto drop;
 561		}
 562	}
 563
 564	/*
 565	 * Place the rndis header in the skb head room and
 566	 * the skb->cb will be used for hv_netvsc_packet
 567	 * structure.
 568	 */
 569	ret = skb_cow_head(skb, RNDIS_AND_PPI_SIZE);
 570	if (ret)
 571		goto no_memory;
 572
 573	/* Use the skb control buffer for building up the packet */
 574	BUILD_BUG_ON(sizeof(struct hv_netvsc_packet) >
 575			sizeof_field(struct sk_buff, cb));
 576	packet = (struct hv_netvsc_packet *)skb->cb;
 577
 578	packet->q_idx = skb_get_queue_mapping(skb);
 579
 
 580	packet->total_data_buflen = skb->len;
 581	packet->total_bytes = skb->len;
 582	packet->total_packets = 1;
 583
 584	rndis_msg = (struct rndis_message *)skb->head;
 
 
 
 
 
 
 
 
 
 585
 586	/* Add the rndis header */
 
 587	rndis_msg->ndis_msg_type = RNDIS_MSG_PACKET;
 588	rndis_msg->msg_len = packet->total_data_buflen;
 
 
 
 
 589
 590	rndis_msg->msg.pkt = (struct rndis_packet) {
 591		.data_offset = sizeof(struct rndis_packet),
 592		.data_len = packet->total_data_buflen,
 593		.per_pkt_info_offset = sizeof(struct rndis_packet),
 594	};
 595
 596	rndis_msg_size = RNDIS_MESSAGE_SIZE(struct rndis_packet);
 
 597
 598	hash = skb_get_hash_raw(skb);
 599	if (hash != 0 && net->real_num_tx_queues > 1) {
 600		u32 *hash_info;
 601
 602		rndis_msg_size += NDIS_HASH_PPI_SIZE;
 603		hash_info = init_ppi_data(rndis_msg, NDIS_HASH_PPI_SIZE,
 604					  NBL_HASH_VALUE);
 605		*hash_info = hash;
 606	}
 607
 608	/* When using AF_PACKET we need to drop VLAN header from
 609	 * the frame and update the SKB to allow the HOST OS
 610	 * to transmit the 802.1Q packet
 
 
 
 
 611	 */
 612	if (skb->protocol == htons(ETH_P_8021Q)) {
 613		u16 vlan_tci;
 
 
 
 
 614
 615		skb_reset_mac_header(skb);
 616		if (eth_type_vlan(eth_hdr(skb)->h_proto)) {
 617			if (unlikely(__skb_vlan_pop(skb, &vlan_tci) != 0)) {
 618				++net_device_ctx->eth_stats.vlan_error;
 619				goto drop;
 620			}
 621
 622			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tci);
 623			/* Update the NDIS header pkt lengths */
 624			packet->total_data_buflen -= VLAN_HLEN;
 625			packet->total_bytes -= VLAN_HLEN;
 626			rndis_msg->msg_len = packet->total_data_buflen;
 627			rndis_msg->msg.pkt.data_len = packet->total_data_buflen;
 628		}
 629	}
 630
 631	if (skb_vlan_tag_present(skb)) {
 632		struct ndis_pkt_8021q_info *vlan;
 
 
 
 
 
 
 
 
 
 
 633
 634		rndis_msg_size += NDIS_VLAN_PPI_SIZE;
 635		vlan = init_ppi_data(rndis_msg, NDIS_VLAN_PPI_SIZE,
 636				     IEEE_8021Q_INFO);
 637
 638		vlan->value = 0;
 639		vlan->vlanid = skb_vlan_tag_get_id(skb);
 640		vlan->cfi = skb_vlan_tag_get_cfi(skb);
 641		vlan->pri = skb_vlan_tag_get_prio(skb);
 642	}
 643
 644	if (skb_is_gso(skb)) {
 645		struct ndis_tcp_lso_info *lso_info;
 646
 647		rndis_msg_size += NDIS_LSO_PPI_SIZE;
 648		lso_info = init_ppi_data(rndis_msg, NDIS_LSO_PPI_SIZE,
 649					 TCP_LARGESEND_PKTINFO);
 650
 651		lso_info->value = 0;
 652		lso_info->lso_v2_transmit.type = NDIS_TCP_LARGE_SEND_OFFLOAD_V2_TYPE;
 653		if (skb->protocol == htons(ETH_P_IP)) {
 654			lso_info->lso_v2_transmit.ip_version =
 655				NDIS_TCP_LARGE_SEND_OFFLOAD_IPV4;
 656			ip_hdr(skb)->tot_len = 0;
 657			ip_hdr(skb)->check = 0;
 658			tcp_hdr(skb)->check =
 659				~csum_tcpudp_magic(ip_hdr(skb)->saddr,
 660						   ip_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
 661		} else {
 662			lso_info->lso_v2_transmit.ip_version =
 663				NDIS_TCP_LARGE_SEND_OFFLOAD_IPV6;
 664			tcp_v6_gso_csum_prep(skb);
 665		}
 666		lso_info->lso_v2_transmit.tcp_header_offset = skb_transport_offset(skb);
 667		lso_info->lso_v2_transmit.mss = skb_shinfo(skb)->gso_size;
 668	} else if (skb->ip_summed == CHECKSUM_PARTIAL) {
 669		if (net_checksum_info(skb) & net_device_ctx->tx_checksum_mask) {
 670			struct ndis_tcp_ip_checksum_info *csum_info;
 671
 672			rndis_msg_size += NDIS_CSUM_PPI_SIZE;
 673			csum_info = init_ppi_data(rndis_msg, NDIS_CSUM_PPI_SIZE,
 674						  TCPIP_CHKSUM_PKTINFO);
 675
 676			csum_info->value = 0;
 677			csum_info->transmit.tcp_header_offset = skb_transport_offset(skb);
 678
 679			if (skb->protocol == htons(ETH_P_IP)) {
 680				csum_info->transmit.is_ipv4 = 1;
 681
 682				if (ip_hdr(skb)->protocol == IPPROTO_TCP)
 683					csum_info->transmit.tcp_checksum = 1;
 684				else
 685					csum_info->transmit.udp_checksum = 1;
 686			} else {
 687				csum_info->transmit.is_ipv6 = 1;
 688
 689				if (ipv6_hdr(skb)->nexthdr == IPPROTO_TCP)
 690					csum_info->transmit.tcp_checksum = 1;
 691				else
 692					csum_info->transmit.udp_checksum = 1;
 693			}
 694		} else {
 695			/* Can't do offload of this type of checksum */
 696			if (skb_checksum_help(skb))
 697				goto drop;
 698		}
 699	}
 
 
 700
 
 701	/* Start filling in the page buffers with the rndis hdr */
 702	rndis_msg->msg_len += rndis_msg_size;
 703	packet->total_data_buflen = rndis_msg->msg_len;
 704	packet->page_buf_cnt = init_page_array(rndis_msg, rndis_msg_size,
 705					       skb, packet, pb);
 706
 707	/* timestamp packet in software */
 708	skb_tx_timestamp(skb);
 709
 710	ret = netvsc_send(net, packet, rndis_msg, pb, skb, xdp_tx);
 711	if (likely(ret == 0))
 712		return NETDEV_TX_OK;
 713
 714	if (ret == -EAGAIN) {
 715		++net_device_ctx->eth_stats.tx_busy;
 716		return NETDEV_TX_BUSY;
 
 
 
 717	}
 718
 719	if (ret == -ENOSPC)
 720		++net_device_ctx->eth_stats.tx_no_space;
 721
 722drop:
 723	dev_kfree_skb_any(skb);
 724	net->stats.tx_dropped++;
 725
 726	return NETDEV_TX_OK;
 727
 728no_memory:
 729	++net_device_ctx->eth_stats.tx_no_memory;
 730	goto drop;
 731}
 732
 733static netdev_tx_t netvsc_start_xmit(struct sk_buff *skb,
 734				     struct net_device *ndev)
 735{
 736	return netvsc_xmit(skb, ndev, false);
 737}
 738
 739/*
 740 * netvsc_linkstatus_callback - Link up/down notification
 741 */
 742void netvsc_linkstatus_callback(struct net_device *net,
 743				struct rndis_message *resp,
 744				void *data, u32 data_buflen)
 745{
 746	struct rndis_indicate_status *indicate = &resp->msg.indicate_status;
 747	struct net_device_context *ndev_ctx = netdev_priv(net);
 748	struct netvsc_reconfig *event;
 749	unsigned long flags;
 750
 751	/* Ensure the packet is big enough to access its fields */
 752	if (resp->msg_len - RNDIS_HEADER_SIZE < sizeof(struct rndis_indicate_status)) {
 753		netdev_err(net, "invalid rndis_indicate_status packet, len: %u\n",
 754			   resp->msg_len);
 755		return;
 756	}
 757
 758	/* Copy the RNDIS indicate status into nvchan->recv_buf */
 759	memcpy(indicate, data + RNDIS_HEADER_SIZE, sizeof(*indicate));
 760
 761	/* Update the physical link speed when changing to another vSwitch */
 762	if (indicate->status == RNDIS_STATUS_LINK_SPEED_CHANGE) {
 763		u32 speed;
 764
 765		/* Validate status_buf_offset and status_buflen.
 766		 *
 767		 * Certain (pre-Fe) implementations of Hyper-V's vSwitch didn't account
 768		 * for the status buffer field in resp->msg_len; perform the validation
 769		 * using data_buflen (>= resp->msg_len).
 770		 */
 771		if (indicate->status_buflen < sizeof(speed) ||
 772		    indicate->status_buf_offset < sizeof(*indicate) ||
 773		    data_buflen - RNDIS_HEADER_SIZE < indicate->status_buf_offset ||
 774		    data_buflen - RNDIS_HEADER_SIZE - indicate->status_buf_offset
 775				< indicate->status_buflen) {
 776			netdev_err(net, "invalid rndis_indicate_status packet\n");
 777			return;
 778		}
 779
 780		speed = *(u32 *)(data + RNDIS_HEADER_SIZE + indicate->status_buf_offset) / 10000;
 781		ndev_ctx->speed = speed;
 782		return;
 783	}
 784
 785	/* Handle these link change statuses below */
 786	if (indicate->status != RNDIS_STATUS_NETWORK_CHANGE &&
 787	    indicate->status != RNDIS_STATUS_MEDIA_CONNECT &&
 788	    indicate->status != RNDIS_STATUS_MEDIA_DISCONNECT)
 789		return;
 790
 791	if (net->reg_state != NETREG_REGISTERED)
 792		return;
 793
 794	event = kzalloc(sizeof(*event), GFP_ATOMIC);
 795	if (!event)
 796		return;
 797	event->event = indicate->status;
 798
 799	spin_lock_irqsave(&ndev_ctx->lock, flags);
 800	list_add_tail(&event->list, &ndev_ctx->reconfig_events);
 801	spin_unlock_irqrestore(&ndev_ctx->lock, flags);
 802
 803	schedule_delayed_work(&ndev_ctx->dwork, 0);
 804}
 805
 806static void netvsc_xdp_xmit(struct sk_buff *skb, struct net_device *ndev)
 807{
 808	int rc;
 809
 810	skb->queue_mapping = skb_get_rx_queue(skb);
 811	__skb_push(skb, ETH_HLEN);
 812
 813	rc = netvsc_xmit(skb, ndev, true);
 814
 815	if (dev_xmit_complete(rc))
 816		return;
 817
 818	dev_kfree_skb_any(skb);
 819	ndev->stats.tx_dropped++;
 820}
 821
 822static void netvsc_comp_ipcsum(struct sk_buff *skb)
 823{
 824	struct iphdr *iph = (struct iphdr *)skb->data;
 825
 826	iph->check = 0;
 827	iph->check = ip_fast_csum(iph, iph->ihl);
 828}
 829
 830static struct sk_buff *netvsc_alloc_recv_skb(struct net_device *net,
 831					     struct netvsc_channel *nvchan,
 832					     struct xdp_buff *xdp)
 833{
 834	struct napi_struct *napi = &nvchan->napi;
 835	const struct ndis_pkt_8021q_info *vlan = &nvchan->rsc.vlan;
 836	const struct ndis_tcp_ip_checksum_info *csum_info =
 837						&nvchan->rsc.csum_info;
 838	const u32 *hash_info = &nvchan->rsc.hash_info;
 839	u8 ppi_flags = nvchan->rsc.ppi_flags;
 840	struct sk_buff *skb;
 841	void *xbuf = xdp->data_hard_start;
 842	int i;
 843
 844	if (xbuf) {
 845		unsigned int hdroom = xdp->data - xdp->data_hard_start;
 846		unsigned int xlen = xdp->data_end - xdp->data;
 847		unsigned int frag_size = xdp->frame_sz;
 848
 849		skb = build_skb(xbuf, frag_size);
 850
 851		if (!skb) {
 852			__free_page(virt_to_page(xbuf));
 853			return NULL;
 854		}
 855
 856		skb_reserve(skb, hdroom);
 857		skb_put(skb, xlen);
 858		skb->dev = napi->dev;
 859	} else {
 860		skb = napi_alloc_skb(napi, nvchan->rsc.pktlen);
 861
 862		if (!skb)
 863			return NULL;
 864
 865		/* Copy to skb. This copy is needed here since the memory
 866		 * pointed by hv_netvsc_packet cannot be deallocated.
 867		 */
 868		for (i = 0; i < nvchan->rsc.cnt; i++)
 869			skb_put_data(skb, nvchan->rsc.data[i],
 870				     nvchan->rsc.len[i]);
 871	}
 872
 873	skb->protocol = eth_type_trans(skb, net);
 874
 875	/* skb is already created with CHECKSUM_NONE */
 876	skb_checksum_none_assert(skb);
 877
 878	/* Incoming packets may have IP header checksum verified by the host.
 879	 * They may not have IP header checksum computed after coalescing.
 880	 * We compute it here if the flags are set, because on Linux, the IP
 881	 * checksum is always checked.
 882	 */
 883	if ((ppi_flags & NVSC_RSC_CSUM_INFO) && csum_info->receive.ip_checksum_value_invalid &&
 884	    csum_info->receive.ip_checksum_succeeded &&
 885	    skb->protocol == htons(ETH_P_IP)) {
 886		/* Check that there is enough space to hold the IP header. */
 887		if (skb_headlen(skb) < sizeof(struct iphdr)) {
 888			kfree_skb(skb);
 889			return NULL;
 890		}
 891		netvsc_comp_ipcsum(skb);
 892	}
 893
 894	/* Do L4 checksum offload if enabled and present. */
 895	if ((ppi_flags & NVSC_RSC_CSUM_INFO) && (net->features & NETIF_F_RXCSUM)) {
 896		if (csum_info->receive.tcp_checksum_succeeded ||
 897		    csum_info->receive.udp_checksum_succeeded)
 898			skb->ip_summed = CHECKSUM_UNNECESSARY;
 899	}
 900
 901	if ((ppi_flags & NVSC_RSC_HASH_INFO) && (net->features & NETIF_F_RXHASH))
 902		skb_set_hash(skb, *hash_info, PKT_HASH_TYPE_L4);
 903
 904	if (ppi_flags & NVSC_RSC_VLAN) {
 905		u16 vlan_tci = vlan->vlanid | (vlan->pri << VLAN_PRIO_SHIFT) |
 906			(vlan->cfi ? VLAN_CFI_MASK : 0);
 907
 908		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
 909				       vlan_tci);
 910	}
 911
 912	return skb;
 913}
 914
 915/*
 916 * netvsc_recv_callback -  Callback when we receive a packet from the
 917 * "wire" on the specified device.
 918 */
 919int netvsc_recv_callback(struct net_device *net,
 920			 struct netvsc_device *net_device,
 921			 struct netvsc_channel *nvchan)
 922{
 923	struct net_device_context *net_device_ctx = netdev_priv(net);
 924	struct vmbus_channel *channel = nvchan->channel;
 925	u16 q_idx = channel->offermsg.offer.sub_channel_index;
 926	struct sk_buff *skb;
 927	struct netvsc_stats *rx_stats = &nvchan->rx_stats;
 928	struct xdp_buff xdp;
 929	u32 act;
 930
 931	if (net->reg_state != NETREG_REGISTERED)
 932		return NVSP_STAT_FAIL;
 933
 934	act = netvsc_run_xdp(net, nvchan, &xdp);
 935
 936	if (act != XDP_PASS && act != XDP_TX) {
 937		u64_stats_update_begin(&rx_stats->syncp);
 938		rx_stats->xdp_drop++;
 939		u64_stats_update_end(&rx_stats->syncp);
 940
 941		return NVSP_STAT_SUCCESS; /* consumed by XDP */
 942	}
 943
 944	/* Allocate a skb - TODO direct I/O to pages? */
 945	skb = netvsc_alloc_recv_skb(net, nvchan, &xdp);
 946
 947	if (unlikely(!skb)) {
 948		++net_device_ctx->eth_stats.rx_no_memory;
 949		return NVSP_STAT_FAIL;
 
 950	}
 951
 952	skb_record_rx_queue(skb, q_idx);
 953
 954	/*
 955	 * Even if injecting the packet, record the statistics
 956	 * on the synthetic device because modifying the VF device
 957	 * statistics will not work correctly.
 958	 */
 959	u64_stats_update_begin(&rx_stats->syncp);
 960	rx_stats->packets++;
 961	rx_stats->bytes += nvchan->rsc.pktlen;
 962
 963	if (skb->pkt_type == PACKET_BROADCAST)
 964		++rx_stats->broadcast;
 965	else if (skb->pkt_type == PACKET_MULTICAST)
 966		++rx_stats->multicast;
 967	u64_stats_update_end(&rx_stats->syncp);
 968
 969	if (act == XDP_TX) {
 970		netvsc_xdp_xmit(skb, net);
 971		return NVSP_STAT_SUCCESS;
 972	}
 973
 974	napi_gro_receive(&nvchan->napi, skb);
 975	return NVSP_STAT_SUCCESS;
 976}
 977
 978static void netvsc_get_drvinfo(struct net_device *net,
 979			       struct ethtool_drvinfo *info)
 980{
 981	strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
 982	strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
 983}
 984
 985static void netvsc_get_channels(struct net_device *net,
 986				struct ethtool_channels *channel)
 987{
 988	struct net_device_context *net_device_ctx = netdev_priv(net);
 989	struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
 990
 991	if (nvdev) {
 992		channel->max_combined	= nvdev->max_chn;
 993		channel->combined_count = nvdev->num_chn;
 994	}
 995}
 996
 997/* Alloc struct netvsc_device_info, and initialize it from either existing
 998 * struct netvsc_device, or from default values.
 999 */
1000static
1001struct netvsc_device_info *netvsc_devinfo_get(struct netvsc_device *nvdev)
1002{
1003	struct netvsc_device_info *dev_info;
1004	struct bpf_prog *prog;
1005
1006	dev_info = kzalloc(sizeof(*dev_info), GFP_ATOMIC);
 
1007
1008	if (!dev_info)
1009		return NULL;
1010
1011	if (nvdev) {
1012		ASSERT_RTNL();
1013
1014		dev_info->num_chn = nvdev->num_chn;
1015		dev_info->send_sections = nvdev->send_section_cnt;
1016		dev_info->send_section_size = nvdev->send_section_size;
1017		dev_info->recv_sections = nvdev->recv_section_cnt;
1018		dev_info->recv_section_size = nvdev->recv_section_size;
1019
1020		memcpy(dev_info->rss_key, nvdev->extension->rss_key,
1021		       NETVSC_HASH_KEYLEN);
1022
1023		prog = netvsc_xdp_get(nvdev);
1024		if (prog) {
1025			bpf_prog_inc(prog);
1026			dev_info->bprog = prog;
1027		}
1028	} else {
1029		dev_info->num_chn = VRSS_CHANNEL_DEFAULT;
1030		dev_info->send_sections = NETVSC_DEFAULT_TX;
1031		dev_info->send_section_size = NETVSC_SEND_SECTION_SIZE;
1032		dev_info->recv_sections = NETVSC_DEFAULT_RX;
1033		dev_info->recv_section_size = NETVSC_RECV_SECTION_SIZE;
1034	}
1035
1036	return dev_info;
1037}
1038
1039/* Free struct netvsc_device_info */
1040static void netvsc_devinfo_put(struct netvsc_device_info *dev_info)
1041{
1042	if (dev_info->bprog) {
1043		ASSERT_RTNL();
1044		bpf_prog_put(dev_info->bprog);
1045	}
1046
1047	kfree(dev_info);
1048}
1049
1050static int netvsc_detach(struct net_device *ndev,
1051			 struct netvsc_device *nvdev)
1052{
1053	struct net_device_context *ndev_ctx = netdev_priv(ndev);
1054	struct hv_device *hdev = ndev_ctx->device_ctx;
1055	int ret;
1056
1057	/* Don't try continuing to try and setup sub channels */
1058	if (cancel_work_sync(&nvdev->subchan_work))
1059		nvdev->num_chn = 1;
1060
1061	netvsc_xdp_set(ndev, NULL, NULL, nvdev);
1062
1063	/* If device was up (receiving) then shutdown */
1064	if (netif_running(ndev)) {
1065		netvsc_tx_disable(nvdev, ndev);
1066
1067		ret = rndis_filter_close(nvdev);
1068		if (ret) {
1069			netdev_err(ndev,
1070				   "unable to close device (ret %d).\n", ret);
1071			return ret;
1072		}
1073
1074		ret = netvsc_wait_until_empty(nvdev);
1075		if (ret) {
1076			netdev_err(ndev,
1077				   "Ring buffer not empty after closing rndis\n");
1078			return ret;
1079		}
1080	}
1081
1082	netif_device_detach(ndev);
1083
1084	rndis_filter_device_remove(hdev, nvdev);
1085
1086	return 0;
1087}
1088
1089static int netvsc_attach(struct net_device *ndev,
1090			 struct netvsc_device_info *dev_info)
1091{
1092	struct net_device_context *ndev_ctx = netdev_priv(ndev);
1093	struct hv_device *hdev = ndev_ctx->device_ctx;
1094	struct netvsc_device *nvdev;
1095	struct rndis_device *rdev;
1096	struct bpf_prog *prog;
1097	int ret = 0;
1098
1099	nvdev = rndis_filter_device_add(hdev, dev_info);
1100	if (IS_ERR(nvdev))
1101		return PTR_ERR(nvdev);
1102
1103	if (nvdev->num_chn > 1) {
1104		ret = rndis_set_subchannel(ndev, nvdev, dev_info);
1105
1106		/* if unavailable, just proceed with one queue */
1107		if (ret) {
1108			nvdev->max_chn = 1;
1109			nvdev->num_chn = 1;
1110		}
1111	}
1112
1113	prog = dev_info->bprog;
1114	if (prog) {
1115		bpf_prog_inc(prog);
1116		ret = netvsc_xdp_set(ndev, prog, NULL, nvdev);
1117		if (ret) {
1118			bpf_prog_put(prog);
1119			goto err1;
1120		}
1121	}
1122
1123	/* In any case device is now ready */
1124	nvdev->tx_disable = false;
1125	netif_device_attach(ndev);
1126
1127	/* Note: enable and attach happen when sub-channels setup */
1128	netif_carrier_off(ndev);
1129
1130	if (netif_running(ndev)) {
1131		ret = rndis_filter_open(nvdev);
1132		if (ret)
1133			goto err2;
1134
1135		rdev = nvdev->extension;
1136		if (!rdev->link_state)
1137			netif_carrier_on(ndev);
1138	}
1139
1140	return 0;
1141
1142err2:
1143	netif_device_detach(ndev);
1144
1145err1:
1146	rndis_filter_device_remove(hdev, nvdev);
1147
1148	return ret;
1149}
1150
1151static int netvsc_set_channels(struct net_device *net,
1152			       struct ethtool_channels *channels)
1153{
1154	struct net_device_context *net_device_ctx = netdev_priv(net);
1155	struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
1156	unsigned int orig, count = channels->combined_count;
1157	struct netvsc_device_info *device_info;
1158	int ret;
1159
1160	/* We do not support separate count for rx, tx, or other */
1161	if (count == 0 ||
1162	    channels->rx_count || channels->tx_count || channels->other_count)
1163		return -EINVAL;
1164
1165	if (!nvdev || nvdev->destroy)
1166		return -ENODEV;
1167
1168	if (nvdev->nvsp_version < NVSP_PROTOCOL_VERSION_5)
1169		return -EINVAL;
1170
1171	if (count > nvdev->max_chn)
1172		return -EINVAL;
1173
1174	orig = nvdev->num_chn;
1175
1176	device_info = netvsc_devinfo_get(nvdev);
1177
1178	if (!device_info)
1179		return -ENOMEM;
1180
1181	device_info->num_chn = count;
1182
1183	ret = netvsc_detach(net, nvdev);
1184	if (ret)
1185		goto out;
1186
1187	ret = netvsc_attach(net, device_info);
1188	if (ret) {
1189		device_info->num_chn = orig;
1190		if (netvsc_attach(net, device_info))
1191			netdev_err(net, "restoring channel setting failed\n");
1192	}
1193
1194out:
1195	netvsc_devinfo_put(device_info);
1196	return ret;
1197}
1198
1199static void netvsc_init_settings(struct net_device *dev)
1200{
1201	struct net_device_context *ndc = netdev_priv(dev);
1202
1203	ndc->l4_hash = HV_DEFAULT_L4HASH;
1204
1205	ndc->speed = SPEED_UNKNOWN;
1206	ndc->duplex = DUPLEX_FULL;
1207
1208	dev->features = NETIF_F_LRO;
1209}
1210
1211static int netvsc_get_link_ksettings(struct net_device *dev,
1212				     struct ethtool_link_ksettings *cmd)
1213{
1214	struct net_device_context *ndc = netdev_priv(dev);
1215	struct net_device *vf_netdev;
1216
1217	vf_netdev = rtnl_dereference(ndc->vf_netdev);
1218
1219	if (vf_netdev)
1220		return __ethtool_get_link_ksettings(vf_netdev, cmd);
1221
1222	cmd->base.speed = ndc->speed;
1223	cmd->base.duplex = ndc->duplex;
1224	cmd->base.port = PORT_OTHER;
1225
1226	return 0;
1227}
1228
1229static int netvsc_set_link_ksettings(struct net_device *dev,
1230				     const struct ethtool_link_ksettings *cmd)
1231{
1232	struct net_device_context *ndc = netdev_priv(dev);
1233	struct net_device *vf_netdev = rtnl_dereference(ndc->vf_netdev);
1234
1235	if (vf_netdev) {
1236		if (!vf_netdev->ethtool_ops->set_link_ksettings)
1237			return -EOPNOTSUPP;
1238
1239		return vf_netdev->ethtool_ops->set_link_ksettings(vf_netdev,
1240								  cmd);
1241	}
1242
1243	return ethtool_virtdev_set_link_ksettings(dev, cmd,
1244						  &ndc->speed, &ndc->duplex);
1245}
1246
1247static int netvsc_change_mtu(struct net_device *ndev, int mtu)
1248{
1249	struct net_device_context *ndevctx = netdev_priv(ndev);
1250	struct net_device *vf_netdev = rtnl_dereference(ndevctx->vf_netdev);
1251	struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
1252	int orig_mtu = ndev->mtu;
1253	struct netvsc_device_info *device_info;
1254	int ret = 0;
1255
1256	if (!nvdev || nvdev->destroy)
1257		return -ENODEV;
1258
1259	device_info = netvsc_devinfo_get(nvdev);
 
1260
1261	if (!device_info)
1262		return -ENOMEM;
1263
1264	/* Change MTU of underlying VF netdev first. */
1265	if (vf_netdev) {
1266		ret = dev_set_mtu(vf_netdev, mtu);
1267		if (ret)
1268			goto out;
1269	}
1270
1271	ret = netvsc_detach(ndev, nvdev);
1272	if (ret)
1273		goto rollback_vf;
1274
1275	ndev->mtu = mtu;
1276
1277	ret = netvsc_attach(ndev, device_info);
1278	if (!ret)
1279		goto out;
1280
1281	/* Attempt rollback to original MTU */
1282	ndev->mtu = orig_mtu;
1283
1284	if (netvsc_attach(ndev, device_info))
1285		netdev_err(ndev, "restoring mtu failed\n");
1286rollback_vf:
1287	if (vf_netdev)
1288		dev_set_mtu(vf_netdev, orig_mtu);
1289
1290out:
1291	netvsc_devinfo_put(device_info);
1292	return ret;
1293}
1294
1295static void netvsc_get_vf_stats(struct net_device *net,
1296				struct netvsc_vf_pcpu_stats *tot)
1297{
1298	struct net_device_context *ndev_ctx = netdev_priv(net);
1299	int i;
1300
1301	memset(tot, 0, sizeof(*tot));
1302
1303	for_each_possible_cpu(i) {
1304		const struct netvsc_vf_pcpu_stats *stats
1305			= per_cpu_ptr(ndev_ctx->vf_stats, i);
1306		u64 rx_packets, rx_bytes, tx_packets, tx_bytes;
1307		unsigned int start;
1308
1309		do {
1310			start = u64_stats_fetch_begin_irq(&stats->syncp);
1311			rx_packets = stats->rx_packets;
1312			tx_packets = stats->tx_packets;
1313			rx_bytes = stats->rx_bytes;
1314			tx_bytes = stats->tx_bytes;
1315		} while (u64_stats_fetch_retry_irq(&stats->syncp, start));
1316
1317		tot->rx_packets += rx_packets;
1318		tot->tx_packets += tx_packets;
1319		tot->rx_bytes   += rx_bytes;
1320		tot->tx_bytes   += tx_bytes;
1321		tot->tx_dropped += stats->tx_dropped;
1322	}
1323}
1324
1325static void netvsc_get_pcpu_stats(struct net_device *net,
1326				  struct netvsc_ethtool_pcpu_stats *pcpu_tot)
1327{
1328	struct net_device_context *ndev_ctx = netdev_priv(net);
1329	struct netvsc_device *nvdev = rcu_dereference_rtnl(ndev_ctx->nvdev);
1330	int i;
1331
1332	/* fetch percpu stats of vf */
1333	for_each_possible_cpu(i) {
1334		const struct netvsc_vf_pcpu_stats *stats =
1335			per_cpu_ptr(ndev_ctx->vf_stats, i);
1336		struct netvsc_ethtool_pcpu_stats *this_tot = &pcpu_tot[i];
1337		unsigned int start;
1338
1339		do {
1340			start = u64_stats_fetch_begin_irq(&stats->syncp);
1341			this_tot->vf_rx_packets = stats->rx_packets;
1342			this_tot->vf_tx_packets = stats->tx_packets;
1343			this_tot->vf_rx_bytes = stats->rx_bytes;
1344			this_tot->vf_tx_bytes = stats->tx_bytes;
1345		} while (u64_stats_fetch_retry_irq(&stats->syncp, start));
1346		this_tot->rx_packets = this_tot->vf_rx_packets;
1347		this_tot->tx_packets = this_tot->vf_tx_packets;
1348		this_tot->rx_bytes   = this_tot->vf_rx_bytes;
1349		this_tot->tx_bytes   = this_tot->vf_tx_bytes;
1350	}
1351
1352	/* fetch percpu stats of netvsc */
1353	for (i = 0; i < nvdev->num_chn; i++) {
1354		const struct netvsc_channel *nvchan = &nvdev->chan_table[i];
1355		const struct netvsc_stats *stats;
1356		struct netvsc_ethtool_pcpu_stats *this_tot =
1357			&pcpu_tot[nvchan->channel->target_cpu];
1358		u64 packets, bytes;
1359		unsigned int start;
1360
1361		stats = &nvchan->tx_stats;
1362		do {
1363			start = u64_stats_fetch_begin_irq(&stats->syncp);
1364			packets = stats->packets;
1365			bytes = stats->bytes;
1366		} while (u64_stats_fetch_retry_irq(&stats->syncp, start));
1367
1368		this_tot->tx_bytes	+= bytes;
1369		this_tot->tx_packets	+= packets;
1370
1371		stats = &nvchan->rx_stats;
1372		do {
1373			start = u64_stats_fetch_begin_irq(&stats->syncp);
1374			packets = stats->packets;
1375			bytes = stats->bytes;
1376		} while (u64_stats_fetch_retry_irq(&stats->syncp, start));
1377
1378		this_tot->rx_bytes	+= bytes;
1379		this_tot->rx_packets	+= packets;
1380	}
1381}
1382
1383static void netvsc_get_stats64(struct net_device *net,
1384			       struct rtnl_link_stats64 *t)
1385{
1386	struct net_device_context *ndev_ctx = netdev_priv(net);
1387	struct netvsc_device *nvdev;
1388	struct netvsc_vf_pcpu_stats vf_tot;
1389	int i;
1390
1391	rcu_read_lock();
1392
1393	nvdev = rcu_dereference(ndev_ctx->nvdev);
1394	if (!nvdev)
1395		goto out;
1396
1397	netdev_stats_to_stats64(t, &net->stats);
1398
1399	netvsc_get_vf_stats(net, &vf_tot);
1400	t->rx_packets += vf_tot.rx_packets;
1401	t->tx_packets += vf_tot.tx_packets;
1402	t->rx_bytes   += vf_tot.rx_bytes;
1403	t->tx_bytes   += vf_tot.tx_bytes;
1404	t->tx_dropped += vf_tot.tx_dropped;
1405
1406	for (i = 0; i < nvdev->num_chn; i++) {
1407		const struct netvsc_channel *nvchan = &nvdev->chan_table[i];
1408		const struct netvsc_stats *stats;
1409		u64 packets, bytes, multicast;
1410		unsigned int start;
1411
1412		stats = &nvchan->tx_stats;
1413		do {
1414			start = u64_stats_fetch_begin_irq(&stats->syncp);
1415			packets = stats->packets;
1416			bytes = stats->bytes;
1417		} while (u64_stats_fetch_retry_irq(&stats->syncp, start));
1418
1419		t->tx_bytes	+= bytes;
1420		t->tx_packets	+= packets;
1421
1422		stats = &nvchan->rx_stats;
1423		do {
1424			start = u64_stats_fetch_begin_irq(&stats->syncp);
1425			packets = stats->packets;
1426			bytes = stats->bytes;
1427			multicast = stats->multicast + stats->broadcast;
1428		} while (u64_stats_fetch_retry_irq(&stats->syncp, start));
1429
1430		t->rx_bytes	+= bytes;
1431		t->rx_packets	+= packets;
1432		t->multicast	+= multicast;
1433	}
1434out:
1435	rcu_read_unlock();
1436}
1437
1438static int netvsc_set_mac_addr(struct net_device *ndev, void *p)
1439{
1440	struct net_device_context *ndc = netdev_priv(ndev);
1441	struct net_device *vf_netdev = rtnl_dereference(ndc->vf_netdev);
1442	struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
1443	struct sockaddr *addr = p;
 
 
1444	int err;
1445
1446	err = eth_prepare_mac_addr_change(ndev, p);
1447	if (err)
 
 
 
1448		return err;
1449
1450	if (!nvdev)
1451		return -ENODEV;
1452
1453	if (vf_netdev) {
1454		err = dev_set_mac_address(vf_netdev, addr, NULL);
1455		if (err)
1456			return err;
1457	}
1458
1459	err = rndis_filter_set_device_mac(nvdev, addr->sa_data);
1460	if (!err) {
1461		eth_commit_mac_addr_change(ndev, p);
1462	} else if (vf_netdev) {
1463		/* rollback change on VF */
1464		memcpy(addr->sa_data, ndev->dev_addr, ETH_ALEN);
1465		dev_set_mac_address(vf_netdev, addr, NULL);
1466	}
1467
1468	return err;
1469}
1470
1471static const struct {
1472	char name[ETH_GSTRING_LEN];
1473	u16 offset;
1474} netvsc_stats[] = {
1475	{ "tx_scattered", offsetof(struct netvsc_ethtool_stats, tx_scattered) },
1476	{ "tx_no_memory", offsetof(struct netvsc_ethtool_stats, tx_no_memory) },
1477	{ "tx_no_space",  offsetof(struct netvsc_ethtool_stats, tx_no_space) },
1478	{ "tx_too_big",	  offsetof(struct netvsc_ethtool_stats, tx_too_big) },
1479	{ "tx_busy",	  offsetof(struct netvsc_ethtool_stats, tx_busy) },
1480	{ "tx_send_full", offsetof(struct netvsc_ethtool_stats, tx_send_full) },
1481	{ "rx_comp_busy", offsetof(struct netvsc_ethtool_stats, rx_comp_busy) },
1482	{ "rx_no_memory", offsetof(struct netvsc_ethtool_stats, rx_no_memory) },
1483	{ "stop_queue", offsetof(struct netvsc_ethtool_stats, stop_queue) },
1484	{ "wake_queue", offsetof(struct netvsc_ethtool_stats, wake_queue) },
1485	{ "vlan_error", offsetof(struct netvsc_ethtool_stats, vlan_error) },
1486}, pcpu_stats[] = {
1487	{ "cpu%u_rx_packets",
1488		offsetof(struct netvsc_ethtool_pcpu_stats, rx_packets) },
1489	{ "cpu%u_rx_bytes",
1490		offsetof(struct netvsc_ethtool_pcpu_stats, rx_bytes) },
1491	{ "cpu%u_tx_packets",
1492		offsetof(struct netvsc_ethtool_pcpu_stats, tx_packets) },
1493	{ "cpu%u_tx_bytes",
1494		offsetof(struct netvsc_ethtool_pcpu_stats, tx_bytes) },
1495	{ "cpu%u_vf_rx_packets",
1496		offsetof(struct netvsc_ethtool_pcpu_stats, vf_rx_packets) },
1497	{ "cpu%u_vf_rx_bytes",
1498		offsetof(struct netvsc_ethtool_pcpu_stats, vf_rx_bytes) },
1499	{ "cpu%u_vf_tx_packets",
1500		offsetof(struct netvsc_ethtool_pcpu_stats, vf_tx_packets) },
1501	{ "cpu%u_vf_tx_bytes",
1502		offsetof(struct netvsc_ethtool_pcpu_stats, vf_tx_bytes) },
1503}, vf_stats[] = {
1504	{ "vf_rx_packets", offsetof(struct netvsc_vf_pcpu_stats, rx_packets) },
1505	{ "vf_rx_bytes",   offsetof(struct netvsc_vf_pcpu_stats, rx_bytes) },
1506	{ "vf_tx_packets", offsetof(struct netvsc_vf_pcpu_stats, tx_packets) },
1507	{ "vf_tx_bytes",   offsetof(struct netvsc_vf_pcpu_stats, tx_bytes) },
1508	{ "vf_tx_dropped", offsetof(struct netvsc_vf_pcpu_stats, tx_dropped) },
1509};
1510
1511#define NETVSC_GLOBAL_STATS_LEN	ARRAY_SIZE(netvsc_stats)
1512#define NETVSC_VF_STATS_LEN	ARRAY_SIZE(vf_stats)
1513
1514/* statistics per queue (rx/tx packets/bytes) */
1515#define NETVSC_PCPU_STATS_LEN (num_present_cpus() * ARRAY_SIZE(pcpu_stats))
1516
1517/* 5 statistics per queue (rx/tx packets/bytes, rx xdp_drop) */
1518#define NETVSC_QUEUE_STATS_LEN(dev) ((dev)->num_chn * 5)
1519
1520static int netvsc_get_sset_count(struct net_device *dev, int string_set)
1521{
1522	struct net_device_context *ndc = netdev_priv(dev);
1523	struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
1524
1525	if (!nvdev)
1526		return -ENODEV;
1527
1528	switch (string_set) {
1529	case ETH_SS_STATS:
1530		return NETVSC_GLOBAL_STATS_LEN
1531			+ NETVSC_VF_STATS_LEN
1532			+ NETVSC_QUEUE_STATS_LEN(nvdev)
1533			+ NETVSC_PCPU_STATS_LEN;
1534	default:
1535		return -EINVAL;
1536	}
1537}
1538
1539static void netvsc_get_ethtool_stats(struct net_device *dev,
1540				     struct ethtool_stats *stats, u64 *data)
1541{
1542	struct net_device_context *ndc = netdev_priv(dev);
1543	struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
1544	const void *nds = &ndc->eth_stats;
1545	const struct netvsc_stats *qstats;
1546	struct netvsc_vf_pcpu_stats sum;
1547	struct netvsc_ethtool_pcpu_stats *pcpu_sum;
1548	unsigned int start;
1549	u64 packets, bytes;
1550	u64 xdp_drop;
1551	int i, j, cpu;
1552
1553	if (!nvdev)
1554		return;
1555
1556	for (i = 0; i < NETVSC_GLOBAL_STATS_LEN; i++)
1557		data[i] = *(unsigned long *)(nds + netvsc_stats[i].offset);
1558
1559	netvsc_get_vf_stats(dev, &sum);
1560	for (j = 0; j < NETVSC_VF_STATS_LEN; j++)
1561		data[i++] = *(u64 *)((void *)&sum + vf_stats[j].offset);
1562
1563	for (j = 0; j < nvdev->num_chn; j++) {
1564		qstats = &nvdev->chan_table[j].tx_stats;
1565
1566		do {
1567			start = u64_stats_fetch_begin_irq(&qstats->syncp);
1568			packets = qstats->packets;
1569			bytes = qstats->bytes;
1570		} while (u64_stats_fetch_retry_irq(&qstats->syncp, start));
1571		data[i++] = packets;
1572		data[i++] = bytes;
1573
1574		qstats = &nvdev->chan_table[j].rx_stats;
1575		do {
1576			start = u64_stats_fetch_begin_irq(&qstats->syncp);
1577			packets = qstats->packets;
1578			bytes = qstats->bytes;
1579			xdp_drop = qstats->xdp_drop;
1580		} while (u64_stats_fetch_retry_irq(&qstats->syncp, start));
1581		data[i++] = packets;
1582		data[i++] = bytes;
1583		data[i++] = xdp_drop;
1584	}
1585
1586	pcpu_sum = kvmalloc_array(num_possible_cpus(),
1587				  sizeof(struct netvsc_ethtool_pcpu_stats),
1588				  GFP_KERNEL);
1589	netvsc_get_pcpu_stats(dev, pcpu_sum);
1590	for_each_present_cpu(cpu) {
1591		struct netvsc_ethtool_pcpu_stats *this_sum = &pcpu_sum[cpu];
1592
1593		for (j = 0; j < ARRAY_SIZE(pcpu_stats); j++)
1594			data[i++] = *(u64 *)((void *)this_sum
1595					     + pcpu_stats[j].offset);
1596	}
1597	kvfree(pcpu_sum);
1598}
1599
1600static void netvsc_get_strings(struct net_device *dev, u32 stringset, u8 *data)
1601{
1602	struct net_device_context *ndc = netdev_priv(dev);
1603	struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
1604	u8 *p = data;
1605	int i, cpu;
1606
1607	if (!nvdev)
1608		return;
1609
1610	switch (stringset) {
1611	case ETH_SS_STATS:
1612		for (i = 0; i < ARRAY_SIZE(netvsc_stats); i++)
1613			ethtool_sprintf(&p, netvsc_stats[i].name);
1614
1615		for (i = 0; i < ARRAY_SIZE(vf_stats); i++)
1616			ethtool_sprintf(&p, vf_stats[i].name);
1617
1618		for (i = 0; i < nvdev->num_chn; i++) {
1619			ethtool_sprintf(&p, "tx_queue_%u_packets", i);
1620			ethtool_sprintf(&p, "tx_queue_%u_bytes", i);
1621			ethtool_sprintf(&p, "rx_queue_%u_packets", i);
1622			ethtool_sprintf(&p, "rx_queue_%u_bytes", i);
1623			ethtool_sprintf(&p, "rx_queue_%u_xdp_drop", i);
1624		}
1625
1626		for_each_present_cpu(cpu) {
1627			for (i = 0; i < ARRAY_SIZE(pcpu_stats); i++)
1628				ethtool_sprintf(&p, pcpu_stats[i].name, cpu);
1629		}
1630
1631		break;
1632	}
1633}
1634
1635static int
1636netvsc_get_rss_hash_opts(struct net_device_context *ndc,
1637			 struct ethtool_rxnfc *info)
1638{
1639	const u32 l4_flag = RXH_L4_B_0_1 | RXH_L4_B_2_3;
1640
1641	info->data = RXH_IP_SRC | RXH_IP_DST;
1642
1643	switch (info->flow_type) {
1644	case TCP_V4_FLOW:
1645		if (ndc->l4_hash & HV_TCP4_L4HASH)
1646			info->data |= l4_flag;
1647
1648		break;
1649
1650	case TCP_V6_FLOW:
1651		if (ndc->l4_hash & HV_TCP6_L4HASH)
1652			info->data |= l4_flag;
1653
1654		break;
1655
1656	case UDP_V4_FLOW:
1657		if (ndc->l4_hash & HV_UDP4_L4HASH)
1658			info->data |= l4_flag;
1659
1660		break;
1661
1662	case UDP_V6_FLOW:
1663		if (ndc->l4_hash & HV_UDP6_L4HASH)
1664			info->data |= l4_flag;
1665
1666		break;
1667
1668	case IPV4_FLOW:
1669	case IPV6_FLOW:
1670		break;
1671	default:
1672		info->data = 0;
1673		break;
1674	}
1675
1676	return 0;
1677}
1678
1679static int
1680netvsc_get_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info,
1681		 u32 *rules)
1682{
1683	struct net_device_context *ndc = netdev_priv(dev);
1684	struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
1685
1686	if (!nvdev)
1687		return -ENODEV;
1688
1689	switch (info->cmd) {
1690	case ETHTOOL_GRXRINGS:
1691		info->data = nvdev->num_chn;
1692		return 0;
1693
1694	case ETHTOOL_GRXFH:
1695		return netvsc_get_rss_hash_opts(ndc, info);
1696	}
1697	return -EOPNOTSUPP;
1698}
1699
1700static int netvsc_set_rss_hash_opts(struct net_device_context *ndc,
1701				    struct ethtool_rxnfc *info)
1702{
1703	if (info->data == (RXH_IP_SRC | RXH_IP_DST |
1704			   RXH_L4_B_0_1 | RXH_L4_B_2_3)) {
1705		switch (info->flow_type) {
1706		case TCP_V4_FLOW:
1707			ndc->l4_hash |= HV_TCP4_L4HASH;
1708			break;
1709
1710		case TCP_V6_FLOW:
1711			ndc->l4_hash |= HV_TCP6_L4HASH;
1712			break;
1713
1714		case UDP_V4_FLOW:
1715			ndc->l4_hash |= HV_UDP4_L4HASH;
1716			break;
1717
1718		case UDP_V6_FLOW:
1719			ndc->l4_hash |= HV_UDP6_L4HASH;
1720			break;
1721
1722		default:
1723			return -EOPNOTSUPP;
1724		}
1725
1726		return 0;
1727	}
1728
1729	if (info->data == (RXH_IP_SRC | RXH_IP_DST)) {
1730		switch (info->flow_type) {
1731		case TCP_V4_FLOW:
1732			ndc->l4_hash &= ~HV_TCP4_L4HASH;
1733			break;
1734
1735		case TCP_V6_FLOW:
1736			ndc->l4_hash &= ~HV_TCP6_L4HASH;
1737			break;
1738
1739		case UDP_V4_FLOW:
1740			ndc->l4_hash &= ~HV_UDP4_L4HASH;
1741			break;
1742
1743		case UDP_V6_FLOW:
1744			ndc->l4_hash &= ~HV_UDP6_L4HASH;
1745			break;
1746
1747		default:
1748			return -EOPNOTSUPP;
1749		}
1750
1751		return 0;
1752	}
1753
1754	return -EOPNOTSUPP;
1755}
1756
1757static int
1758netvsc_set_rxnfc(struct net_device *ndev, struct ethtool_rxnfc *info)
1759{
1760	struct net_device_context *ndc = netdev_priv(ndev);
1761
1762	if (info->cmd == ETHTOOL_SRXFH)
1763		return netvsc_set_rss_hash_opts(ndc, info);
1764
1765	return -EOPNOTSUPP;
1766}
1767
1768static u32 netvsc_get_rxfh_key_size(struct net_device *dev)
1769{
1770	return NETVSC_HASH_KEYLEN;
1771}
1772
1773static u32 netvsc_rss_indir_size(struct net_device *dev)
1774{
1775	return ITAB_NUM;
1776}
1777
1778static int netvsc_get_rxfh(struct net_device *dev, u32 *indir, u8 *key,
1779			   u8 *hfunc)
1780{
1781	struct net_device_context *ndc = netdev_priv(dev);
1782	struct netvsc_device *ndev = rtnl_dereference(ndc->nvdev);
1783	struct rndis_device *rndis_dev;
1784	int i;
1785
1786	if (!ndev)
1787		return -ENODEV;
1788
1789	if (hfunc)
1790		*hfunc = ETH_RSS_HASH_TOP;	/* Toeplitz */
1791
1792	rndis_dev = ndev->extension;
1793	if (indir) {
1794		for (i = 0; i < ITAB_NUM; i++)
1795			indir[i] = ndc->rx_table[i];
1796	}
1797
1798	if (key)
1799		memcpy(key, rndis_dev->rss_key, NETVSC_HASH_KEYLEN);
1800
1801	return 0;
1802}
1803
1804static int netvsc_set_rxfh(struct net_device *dev, const u32 *indir,
1805			   const u8 *key, const u8 hfunc)
1806{
1807	struct net_device_context *ndc = netdev_priv(dev);
1808	struct netvsc_device *ndev = rtnl_dereference(ndc->nvdev);
1809	struct rndis_device *rndis_dev;
1810	int i;
1811
1812	if (!ndev)
1813		return -ENODEV;
1814
1815	if (hfunc != ETH_RSS_HASH_NO_CHANGE && hfunc != ETH_RSS_HASH_TOP)
1816		return -EOPNOTSUPP;
1817
1818	rndis_dev = ndev->extension;
1819	if (indir) {
1820		for (i = 0; i < ITAB_NUM; i++)
1821			if (indir[i] >= ndev->num_chn)
1822				return -EINVAL;
1823
1824		for (i = 0; i < ITAB_NUM; i++)
1825			ndc->rx_table[i] = indir[i];
1826	}
1827
1828	if (!key) {
1829		if (!indir)
1830			return 0;
1831
1832		key = rndis_dev->rss_key;
1833	}
1834
1835	return rndis_filter_set_rss_param(rndis_dev, key);
1836}
1837
1838/* Hyper-V RNDIS protocol does not have ring in the HW sense.
1839 * It does have pre-allocated receive area which is divided into sections.
1840 */
1841static void __netvsc_get_ringparam(struct netvsc_device *nvdev,
1842				   struct ethtool_ringparam *ring)
1843{
1844	u32 max_buf_size;
1845
1846	ring->rx_pending = nvdev->recv_section_cnt;
1847	ring->tx_pending = nvdev->send_section_cnt;
1848
1849	if (nvdev->nvsp_version <= NVSP_PROTOCOL_VERSION_2)
1850		max_buf_size = NETVSC_RECEIVE_BUFFER_SIZE_LEGACY;
1851	else
1852		max_buf_size = NETVSC_RECEIVE_BUFFER_SIZE;
1853
1854	ring->rx_max_pending = max_buf_size / nvdev->recv_section_size;
1855	ring->tx_max_pending = NETVSC_SEND_BUFFER_SIZE
1856		/ nvdev->send_section_size;
1857}
1858
1859static void netvsc_get_ringparam(struct net_device *ndev,
1860				 struct ethtool_ringparam *ring)
1861{
1862	struct net_device_context *ndevctx = netdev_priv(ndev);
1863	struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
1864
1865	if (!nvdev)
1866		return;
1867
1868	__netvsc_get_ringparam(nvdev, ring);
1869}
1870
1871static int netvsc_set_ringparam(struct net_device *ndev,
1872				struct ethtool_ringparam *ring)
1873{
1874	struct net_device_context *ndevctx = netdev_priv(ndev);
1875	struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
1876	struct netvsc_device_info *device_info;
1877	struct ethtool_ringparam orig;
1878	u32 new_tx, new_rx;
1879	int ret = 0;
1880
1881	if (!nvdev || nvdev->destroy)
1882		return -ENODEV;
1883
1884	memset(&orig, 0, sizeof(orig));
1885	__netvsc_get_ringparam(nvdev, &orig);
1886
1887	new_tx = clamp_t(u32, ring->tx_pending,
1888			 NETVSC_MIN_TX_SECTIONS, orig.tx_max_pending);
1889	new_rx = clamp_t(u32, ring->rx_pending,
1890			 NETVSC_MIN_RX_SECTIONS, orig.rx_max_pending);
1891
1892	if (new_tx == orig.tx_pending &&
1893	    new_rx == orig.rx_pending)
1894		return 0;	 /* no change */
1895
1896	device_info = netvsc_devinfo_get(nvdev);
1897
1898	if (!device_info)
1899		return -ENOMEM;
1900
1901	device_info->send_sections = new_tx;
1902	device_info->recv_sections = new_rx;
1903
1904	ret = netvsc_detach(ndev, nvdev);
1905	if (ret)
1906		goto out;
1907
1908	ret = netvsc_attach(ndev, device_info);
1909	if (ret) {
1910		device_info->send_sections = orig.tx_pending;
1911		device_info->recv_sections = orig.rx_pending;
1912
1913		if (netvsc_attach(ndev, device_info))
1914			netdev_err(ndev, "restoring ringparam failed");
1915	}
1916
1917out:
1918	netvsc_devinfo_put(device_info);
1919	return ret;
1920}
1921
1922static netdev_features_t netvsc_fix_features(struct net_device *ndev,
1923					     netdev_features_t features)
1924{
1925	struct net_device_context *ndevctx = netdev_priv(ndev);
1926	struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
1927
1928	if (!nvdev || nvdev->destroy)
1929		return features;
1930
1931	if ((features & NETIF_F_LRO) && netvsc_xdp_get(nvdev)) {
1932		features ^= NETIF_F_LRO;
1933		netdev_info(ndev, "Skip LRO - unsupported with XDP\n");
1934	}
1935
1936	return features;
1937}
1938
1939static int netvsc_set_features(struct net_device *ndev,
1940			       netdev_features_t features)
1941{
1942	netdev_features_t change = features ^ ndev->features;
1943	struct net_device_context *ndevctx = netdev_priv(ndev);
1944	struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
1945	struct net_device *vf_netdev = rtnl_dereference(ndevctx->vf_netdev);
1946	struct ndis_offload_params offloads;
1947	int ret = 0;
1948
1949	if (!nvdev || nvdev->destroy)
1950		return -ENODEV;
1951
1952	if (!(change & NETIF_F_LRO))
1953		goto syncvf;
1954
1955	memset(&offloads, 0, sizeof(struct ndis_offload_params));
1956
1957	if (features & NETIF_F_LRO) {
1958		offloads.rsc_ip_v4 = NDIS_OFFLOAD_PARAMETERS_RSC_ENABLED;
1959		offloads.rsc_ip_v6 = NDIS_OFFLOAD_PARAMETERS_RSC_ENABLED;
1960	} else {
1961		offloads.rsc_ip_v4 = NDIS_OFFLOAD_PARAMETERS_RSC_DISABLED;
1962		offloads.rsc_ip_v6 = NDIS_OFFLOAD_PARAMETERS_RSC_DISABLED;
1963	}
1964
1965	ret = rndis_filter_set_offload_params(ndev, nvdev, &offloads);
1966
1967	if (ret) {
1968		features ^= NETIF_F_LRO;
1969		ndev->features = features;
1970	}
1971
1972syncvf:
1973	if (!vf_netdev)
1974		return ret;
1975
1976	vf_netdev->wanted_features = features;
1977	netdev_update_features(vf_netdev);
1978
1979	return ret;
1980}
1981
1982static int netvsc_get_regs_len(struct net_device *netdev)
1983{
1984	return VRSS_SEND_TAB_SIZE * sizeof(u32);
1985}
1986
1987static void netvsc_get_regs(struct net_device *netdev,
1988			    struct ethtool_regs *regs, void *p)
1989{
1990	struct net_device_context *ndc = netdev_priv(netdev);
1991	u32 *regs_buff = p;
1992
1993	/* increase the version, if buffer format is changed. */
1994	regs->version = 1;
1995
1996	memcpy(regs_buff, ndc->tx_table, VRSS_SEND_TAB_SIZE * sizeof(u32));
1997}
1998
1999static u32 netvsc_get_msglevel(struct net_device *ndev)
2000{
2001	struct net_device_context *ndev_ctx = netdev_priv(ndev);
2002
2003	return ndev_ctx->msg_enable;
2004}
2005
2006static void netvsc_set_msglevel(struct net_device *ndev, u32 val)
2007{
2008	struct net_device_context *ndev_ctx = netdev_priv(ndev);
2009
2010	ndev_ctx->msg_enable = val;
2011}
2012
2013static const struct ethtool_ops ethtool_ops = {
2014	.get_drvinfo	= netvsc_get_drvinfo,
2015	.get_regs_len	= netvsc_get_regs_len,
2016	.get_regs	= netvsc_get_regs,
2017	.get_msglevel	= netvsc_get_msglevel,
2018	.set_msglevel	= netvsc_set_msglevel,
2019	.get_link	= ethtool_op_get_link,
2020	.get_ethtool_stats = netvsc_get_ethtool_stats,
2021	.get_sset_count = netvsc_get_sset_count,
2022	.get_strings	= netvsc_get_strings,
2023	.get_channels   = netvsc_get_channels,
2024	.set_channels   = netvsc_set_channels,
2025	.get_ts_info	= ethtool_op_get_ts_info,
2026	.get_rxnfc	= netvsc_get_rxnfc,
2027	.set_rxnfc	= netvsc_set_rxnfc,
2028	.get_rxfh_key_size = netvsc_get_rxfh_key_size,
2029	.get_rxfh_indir_size = netvsc_rss_indir_size,
2030	.get_rxfh	= netvsc_get_rxfh,
2031	.set_rxfh	= netvsc_set_rxfh,
2032	.get_link_ksettings = netvsc_get_link_ksettings,
2033	.set_link_ksettings = netvsc_set_link_ksettings,
2034	.get_ringparam	= netvsc_get_ringparam,
2035	.set_ringparam	= netvsc_set_ringparam,
2036};
2037
2038static const struct net_device_ops device_ops = {
2039	.ndo_open =			netvsc_open,
2040	.ndo_stop =			netvsc_close,
2041	.ndo_start_xmit =		netvsc_start_xmit,
2042	.ndo_change_rx_flags =		netvsc_change_rx_flags,
2043	.ndo_set_rx_mode =		netvsc_set_rx_mode,
2044	.ndo_fix_features =		netvsc_fix_features,
2045	.ndo_set_features =		netvsc_set_features,
2046	.ndo_change_mtu =		netvsc_change_mtu,
2047	.ndo_validate_addr =		eth_validate_addr,
2048	.ndo_set_mac_address =		netvsc_set_mac_addr,
2049	.ndo_select_queue =		netvsc_select_queue,
2050	.ndo_get_stats64 =		netvsc_get_stats64,
2051	.ndo_bpf =			netvsc_bpf,
2052};
2053
2054/*
2055 * Handle link status changes. For RNDIS_STATUS_NETWORK_CHANGE emulate link
2056 * down/up sequence. In case of RNDIS_STATUS_MEDIA_CONNECT when carrier is
2057 * present send GARP packet to network peers with netif_notify_peers().
 
 
 
2058 */
2059static void netvsc_link_change(struct work_struct *w)
2060{
2061	struct net_device_context *ndev_ctx =
2062		container_of(w, struct net_device_context, dwork.work);
2063	struct hv_device *device_obj = ndev_ctx->device_ctx;
2064	struct net_device *net = hv_get_drvdata(device_obj);
2065	unsigned long flags, next_reconfig, delay;
2066	struct netvsc_reconfig *event = NULL;
2067	struct netvsc_device *net_device;
2068	struct rndis_device *rdev;
2069	bool reschedule = false;
2070
2071	/* if changes are happening, comeback later */
2072	if (!rtnl_trylock()) {
2073		schedule_delayed_work(&ndev_ctx->dwork, LINKCHANGE_INT);
2074		return;
2075	}
2076
2077	net_device = rtnl_dereference(ndev_ctx->nvdev);
2078	if (!net_device)
2079		goto out_unlock;
2080
 
 
2081	rdev = net_device->extension;
 
2082
2083	next_reconfig = ndev_ctx->last_reconfig + LINKCHANGE_INT;
2084	if (time_is_after_jiffies(next_reconfig)) {
2085		/* link_watch only sends one notification with current state
2086		 * per second, avoid doing reconfig more frequently. Handle
2087		 * wrap around.
2088		 */
2089		delay = next_reconfig - jiffies;
2090		delay = delay < LINKCHANGE_INT ? delay : LINKCHANGE_INT;
2091		schedule_delayed_work(&ndev_ctx->dwork, delay);
2092		goto out_unlock;
2093	}
2094	ndev_ctx->last_reconfig = jiffies;
2095
2096	spin_lock_irqsave(&ndev_ctx->lock, flags);
2097	if (!list_empty(&ndev_ctx->reconfig_events)) {
2098		event = list_first_entry(&ndev_ctx->reconfig_events,
2099					 struct netvsc_reconfig, list);
2100		list_del(&event->list);
2101		reschedule = !list_empty(&ndev_ctx->reconfig_events);
2102	}
2103	spin_unlock_irqrestore(&ndev_ctx->lock, flags);
2104
2105	if (!event)
2106		goto out_unlock;
2107
2108	switch (event->event) {
2109		/* Only the following events are possible due to the check in
2110		 * netvsc_linkstatus_callback()
2111		 */
2112	case RNDIS_STATUS_MEDIA_CONNECT:
2113		if (rdev->link_state) {
2114			rdev->link_state = false;
2115			netif_carrier_on(net);
2116			netvsc_tx_enable(net_device, net);
2117		} else {
2118			__netdev_notify_peers(net);
2119		}
2120		kfree(event);
2121		break;
2122	case RNDIS_STATUS_MEDIA_DISCONNECT:
2123		if (!rdev->link_state) {
2124			rdev->link_state = true;
2125			netif_carrier_off(net);
2126			netvsc_tx_disable(net_device, net);
2127		}
2128		kfree(event);
2129		break;
2130	case RNDIS_STATUS_NETWORK_CHANGE:
2131		/* Only makes sense if carrier is present */
2132		if (!rdev->link_state) {
2133			rdev->link_state = true;
2134			netif_carrier_off(net);
2135			netvsc_tx_disable(net_device, net);
2136			event->event = RNDIS_STATUS_MEDIA_CONNECT;
2137			spin_lock_irqsave(&ndev_ctx->lock, flags);
2138			list_add(&event->list, &ndev_ctx->reconfig_events);
2139			spin_unlock_irqrestore(&ndev_ctx->lock, flags);
2140			reschedule = true;
2141		}
2142		break;
2143	}
2144
2145	rtnl_unlock();
2146
2147	/* link_watch only sends one notification with current state per
2148	 * second, handle next reconfig event in 2 seconds.
2149	 */
2150	if (reschedule)
2151		schedule_delayed_work(&ndev_ctx->dwork, LINKCHANGE_INT);
2152
2153	return;
2154
2155out_unlock:
2156	rtnl_unlock();
2157}
2158
2159static struct net_device *get_netvsc_byref(struct net_device *vf_netdev)
2160{
2161	struct net_device_context *net_device_ctx;
2162	struct net_device *dev;
2163
2164	dev = netdev_master_upper_dev_get(vf_netdev);
2165	if (!dev || dev->netdev_ops != &device_ops)
2166		return NULL;	/* not a netvsc device */
2167
2168	net_device_ctx = netdev_priv(dev);
2169	if (!rtnl_dereference(net_device_ctx->nvdev))
2170		return NULL;	/* device is removed */
2171
2172	return dev;
2173}
2174
2175/* Called when VF is injecting data into network stack.
2176 * Change the associated network device from VF to netvsc.
2177 * note: already called with rcu_read_lock
2178 */
2179static rx_handler_result_t netvsc_vf_handle_frame(struct sk_buff **pskb)
2180{
2181	struct sk_buff *skb = *pskb;
2182	struct net_device *ndev = rcu_dereference(skb->dev->rx_handler_data);
2183	struct net_device_context *ndev_ctx = netdev_priv(ndev);
2184	struct netvsc_vf_pcpu_stats *pcpu_stats
2185		 = this_cpu_ptr(ndev_ctx->vf_stats);
2186
2187	skb = skb_share_check(skb, GFP_ATOMIC);
2188	if (unlikely(!skb))
2189		return RX_HANDLER_CONSUMED;
2190
2191	*pskb = skb;
2192
2193	skb->dev = ndev;
2194
2195	u64_stats_update_begin(&pcpu_stats->syncp);
2196	pcpu_stats->rx_packets++;
2197	pcpu_stats->rx_bytes += skb->len;
2198	u64_stats_update_end(&pcpu_stats->syncp);
2199
2200	return RX_HANDLER_ANOTHER;
2201}
2202
2203static int netvsc_vf_join(struct net_device *vf_netdev,
2204			  struct net_device *ndev)
2205{
2206	struct net_device_context *ndev_ctx = netdev_priv(ndev);
2207	int ret;
2208
2209	ret = netdev_rx_handler_register(vf_netdev,
2210					 netvsc_vf_handle_frame, ndev);
2211	if (ret != 0) {
2212		netdev_err(vf_netdev,
2213			   "can not register netvsc VF receive handler (err = %d)\n",
2214			   ret);
2215		goto rx_handler_failed;
2216	}
2217
2218	ret = netdev_master_upper_dev_link(vf_netdev, ndev,
2219					   NULL, NULL, NULL);
2220	if (ret != 0) {
2221		netdev_err(vf_netdev,
2222			   "can not set master device %s (err = %d)\n",
2223			   ndev->name, ret);
2224		goto upper_link_failed;
2225	}
2226
2227	/* set slave flag before open to prevent IPv6 addrconf */
2228	vf_netdev->flags |= IFF_SLAVE;
2229
2230	schedule_delayed_work(&ndev_ctx->vf_takeover, VF_TAKEOVER_INT);
2231
2232	call_netdevice_notifiers(NETDEV_JOIN, vf_netdev);
2233
2234	netdev_info(vf_netdev, "joined to %s\n", ndev->name);
2235	return 0;
2236
2237upper_link_failed:
2238	netdev_rx_handler_unregister(vf_netdev);
2239rx_handler_failed:
2240	return ret;
2241}
2242
2243static void __netvsc_vf_setup(struct net_device *ndev,
2244			      struct net_device *vf_netdev)
2245{
2246	int ret;
2247
2248	/* Align MTU of VF with master */
2249	ret = dev_set_mtu(vf_netdev, ndev->mtu);
2250	if (ret)
2251		netdev_warn(vf_netdev,
2252			    "unable to change mtu to %u\n", ndev->mtu);
2253
2254	/* set multicast etc flags on VF */
2255	dev_change_flags(vf_netdev, ndev->flags | IFF_SLAVE, NULL);
2256
2257	/* sync address list from ndev to VF */
2258	netif_addr_lock_bh(ndev);
2259	dev_uc_sync(vf_netdev, ndev);
2260	dev_mc_sync(vf_netdev, ndev);
2261	netif_addr_unlock_bh(ndev);
2262
2263	if (netif_running(ndev)) {
2264		ret = dev_open(vf_netdev, NULL);
2265		if (ret)
2266			netdev_warn(vf_netdev,
2267				    "unable to open: %d\n", ret);
2268	}
2269}
2270
2271/* Setup VF as slave of the synthetic device.
2272 * Runs in workqueue to avoid recursion in netlink callbacks.
2273 */
2274static void netvsc_vf_setup(struct work_struct *w)
2275{
2276	struct net_device_context *ndev_ctx
2277		= container_of(w, struct net_device_context, vf_takeover.work);
2278	struct net_device *ndev = hv_get_drvdata(ndev_ctx->device_ctx);
2279	struct net_device *vf_netdev;
2280
2281	if (!rtnl_trylock()) {
2282		schedule_delayed_work(&ndev_ctx->vf_takeover, 0);
2283		return;
2284	}
2285
2286	vf_netdev = rtnl_dereference(ndev_ctx->vf_netdev);
2287	if (vf_netdev)
2288		__netvsc_vf_setup(ndev, vf_netdev);
2289
2290	rtnl_unlock();
2291}
2292
2293/* Find netvsc by VF serial number.
2294 * The PCI hyperv controller records the serial number as the slot kobj name.
2295 */
2296static struct net_device *get_netvsc_byslot(const struct net_device *vf_netdev)
2297{
2298	struct device *parent = vf_netdev->dev.parent;
2299	struct net_device_context *ndev_ctx;
2300	struct net_device *ndev;
2301	struct pci_dev *pdev;
2302	u32 serial;
2303
2304	if (!parent || !dev_is_pci(parent))
2305		return NULL; /* not a PCI device */
2306
2307	pdev = to_pci_dev(parent);
2308	if (!pdev->slot) {
2309		netdev_notice(vf_netdev, "no PCI slot information\n");
2310		return NULL;
2311	}
2312
2313	if (kstrtou32(pci_slot_name(pdev->slot), 10, &serial)) {
2314		netdev_notice(vf_netdev, "Invalid vf serial:%s\n",
2315			      pci_slot_name(pdev->slot));
2316		return NULL;
2317	}
2318
2319	list_for_each_entry(ndev_ctx, &netvsc_dev_list, list) {
2320		if (!ndev_ctx->vf_alloc)
2321			continue;
2322
2323		if (ndev_ctx->vf_serial != serial)
2324			continue;
2325
2326		ndev = hv_get_drvdata(ndev_ctx->device_ctx);
2327		if (ndev->addr_len != vf_netdev->addr_len ||
2328		    memcmp(ndev->perm_addr, vf_netdev->perm_addr,
2329			   ndev->addr_len) != 0)
2330			continue;
2331
2332		return ndev;
2333
2334	}
2335
2336	netdev_notice(vf_netdev,
2337		      "no netdev found for vf serial:%u\n", serial);
2338	return NULL;
2339}
2340
2341static int netvsc_register_vf(struct net_device *vf_netdev)
2342{
2343	struct net_device_context *net_device_ctx;
2344	struct netvsc_device *netvsc_dev;
2345	struct bpf_prog *prog;
2346	struct net_device *ndev;
2347	int ret;
2348
2349	if (vf_netdev->addr_len != ETH_ALEN)
2350		return NOTIFY_DONE;
2351
2352	ndev = get_netvsc_byslot(vf_netdev);
2353	if (!ndev)
2354		return NOTIFY_DONE;
2355
2356	net_device_ctx = netdev_priv(ndev);
2357	netvsc_dev = rtnl_dereference(net_device_ctx->nvdev);
2358	if (!netvsc_dev || rtnl_dereference(net_device_ctx->vf_netdev))
2359		return NOTIFY_DONE;
2360
2361	/* if synthetic interface is a different namespace,
2362	 * then move the VF to that namespace; join will be
2363	 * done again in that context.
2364	 */
2365	if (!net_eq(dev_net(ndev), dev_net(vf_netdev))) {
2366		ret = dev_change_net_namespace(vf_netdev,
2367					       dev_net(ndev), "eth%d");
2368		if (ret)
2369			netdev_err(vf_netdev,
2370				   "could not move to same namespace as %s: %d\n",
2371				   ndev->name, ret);
2372		else
2373			netdev_info(vf_netdev,
2374				    "VF moved to namespace with: %s\n",
2375				    ndev->name);
2376		return NOTIFY_DONE;
2377	}
2378
2379	netdev_info(ndev, "VF registering: %s\n", vf_netdev->name);
2380
2381	if (netvsc_vf_join(vf_netdev, ndev) != 0)
2382		return NOTIFY_DONE;
2383
2384	dev_hold(vf_netdev);
2385	rcu_assign_pointer(net_device_ctx->vf_netdev, vf_netdev);
2386
2387	if (ndev->needed_headroom < vf_netdev->needed_headroom)
2388		ndev->needed_headroom = vf_netdev->needed_headroom;
2389
2390	vf_netdev->wanted_features = ndev->features;
2391	netdev_update_features(vf_netdev);
2392
2393	prog = netvsc_xdp_get(netvsc_dev);
2394	netvsc_vf_setxdp(vf_netdev, prog);
2395
2396	return NOTIFY_OK;
2397}
2398
2399/* Change the data path when VF UP/DOWN/CHANGE are detected.
2400 *
2401 * Typically a UP or DOWN event is followed by a CHANGE event, so
2402 * net_device_ctx->data_path_is_vf is used to cache the current data path
2403 * to avoid the duplicate call of netvsc_switch_datapath() and the duplicate
2404 * message.
2405 *
2406 * During hibernation, if a VF NIC driver (e.g. mlx5) preserves the network
2407 * interface, there is only the CHANGE event and no UP or DOWN event.
2408 */
2409static int netvsc_vf_changed(struct net_device *vf_netdev, unsigned long event)
2410{
2411	struct net_device_context *net_device_ctx;
2412	struct netvsc_device *netvsc_dev;
2413	struct net_device *ndev;
2414	bool vf_is_up = false;
2415	int ret;
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	ret = netvsc_switch_datapath(ndev, vf_is_up);
2433
2434	if (ret) {
2435		netdev_err(ndev,
2436			   "Data path failed to switch %s VF: %s, err: %d\n",
2437			   vf_is_up ? "to" : "from", vf_netdev->name, ret);
2438		return NOTIFY_DONE;
2439	} else {
2440		netdev_info(ndev, "Data path switched %s VF: %s\n",
2441			    vf_is_up ? "to" : "from", vf_netdev->name);
2442	}
2443
2444	return NOTIFY_OK;
2445}
2446
2447static int netvsc_unregister_vf(struct net_device *vf_netdev)
2448{
2449	struct net_device *ndev;
2450	struct net_device_context *net_device_ctx;
2451
2452	ndev = get_netvsc_byref(vf_netdev);
2453	if (!ndev)
2454		return NOTIFY_DONE;
2455
2456	net_device_ctx = netdev_priv(ndev);
2457	cancel_delayed_work_sync(&net_device_ctx->vf_takeover);
2458
2459	netdev_info(ndev, "VF unregistering: %s\n", vf_netdev->name);
2460
2461	netvsc_vf_setxdp(vf_netdev, NULL);
2462
2463	netdev_rx_handler_unregister(vf_netdev);
2464	netdev_upper_dev_unlink(vf_netdev, ndev);
2465	RCU_INIT_POINTER(net_device_ctx->vf_netdev, NULL);
2466	dev_put(vf_netdev);
2467
2468	ndev->needed_headroom = RNDIS_AND_PPI_SIZE;
2469
2470	return NOTIFY_OK;
2471}
2472
2473static int netvsc_probe(struct hv_device *dev,
2474			const struct hv_vmbus_device_id *dev_id)
2475{
2476	struct net_device *net = NULL;
2477	struct net_device_context *net_device_ctx;
2478	struct netvsc_device_info *device_info = NULL;
2479	struct netvsc_device *nvdev;
2480	int ret = -ENOMEM;
2481
2482	net = alloc_etherdev_mq(sizeof(struct net_device_context),
2483				VRSS_CHANNEL_MAX);
2484	if (!net)
2485		goto no_net;
2486
2487	netif_carrier_off(net);
2488
2489	netvsc_init_settings(net);
2490
2491	net_device_ctx = netdev_priv(net);
2492	net_device_ctx->device_ctx = dev;
2493	net_device_ctx->msg_enable = netif_msg_init(debug, default_msg);
2494	if (netif_msg_probe(net_device_ctx))
2495		netdev_dbg(net, "netvsc msg_enable: %d\n",
2496			   net_device_ctx->msg_enable);
2497
2498	hv_set_drvdata(dev, net);
2499
2500	INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_link_change);
2501
2502	spin_lock_init(&net_device_ctx->lock);
2503	INIT_LIST_HEAD(&net_device_ctx->reconfig_events);
2504	INIT_DELAYED_WORK(&net_device_ctx->vf_takeover, netvsc_vf_setup);
2505
2506	net_device_ctx->vf_stats
2507		= netdev_alloc_pcpu_stats(struct netvsc_vf_pcpu_stats);
2508	if (!net_device_ctx->vf_stats)
2509		goto no_stats;
2510
2511	net->netdev_ops = &device_ops;
2512	net->ethtool_ops = &ethtool_ops;
2513	SET_NETDEV_DEV(net, &dev->device);
2514
2515	/* We always need headroom for rndis header */
2516	net->needed_headroom = RNDIS_AND_PPI_SIZE;
 
 
2517
2518	/* Initialize the number of queues to be 1, we may change it if more
2519	 * channels are offered later.
2520	 */
2521	netif_set_real_num_tx_queues(net, 1);
2522	netif_set_real_num_rx_queues(net, 1);
2523
2524	/* Notify the netvsc driver of the new device */
2525	device_info = netvsc_devinfo_get(NULL);
2526
2527	if (!device_info) {
2528		ret = -ENOMEM;
2529		goto devinfo_failed;
2530	}
2531
2532	nvdev = rndis_filter_device_add(dev, device_info);
2533	if (IS_ERR(nvdev)) {
2534		ret = PTR_ERR(nvdev);
2535		netdev_err(net, "unable to add netvsc device (ret %d)\n", ret);
2536		goto rndis_failed;
 
 
2537	}
 
2538
2539	memcpy(net->dev_addr, device_info->mac_adr, ETH_ALEN);
2540
2541	/* We must get rtnl lock before scheduling nvdev->subchan_work,
2542	 * otherwise netvsc_subchan_work() can get rtnl lock first and wait
2543	 * all subchannels to show up, but that may not happen because
2544	 * netvsc_probe() can't get rtnl lock and as a result vmbus_onoffer()
2545	 * -> ... -> device_add() -> ... -> __device_attach() can't get
2546	 * the device lock, so all the subchannels can't be processed --
2547	 * finally netvsc_subchan_work() hangs forever.
2548	 */
2549	rtnl_lock();
2550
2551	if (nvdev->num_chn > 1)
2552		schedule_work(&nvdev->subchan_work);
2553
2554	/* hw_features computed in rndis_netdev_set_hwcaps() */
2555	net->features = net->hw_features |
2556		NETIF_F_HIGHDMA | NETIF_F_HW_VLAN_CTAG_TX |
2557		NETIF_F_HW_VLAN_CTAG_RX;
2558	net->vlan_features = net->features;
2559
2560	netdev_lockdep_set_classes(net);
2561
2562	/* MTU range: 68 - 1500 or 65521 */
2563	net->min_mtu = NETVSC_MTU_MIN;
2564	if (nvdev->nvsp_version >= NVSP_PROTOCOL_VERSION_2)
2565		net->max_mtu = NETVSC_MTU - ETH_HLEN;
2566	else
2567		net->max_mtu = ETH_DATA_LEN;
2568
2569	nvdev->tx_disable = false;
2570
2571	ret = register_netdevice(net);
2572	if (ret != 0) {
2573		pr_err("Unable to register netdev.\n");
2574		goto register_failed;
 
 
 
2575	}
2576
2577	list_add(&net_device_ctx->list, &netvsc_dev_list);
2578	rtnl_unlock();
2579
2580	netvsc_devinfo_put(device_info);
2581	return 0;
2582
2583register_failed:
2584	rtnl_unlock();
2585	rndis_filter_device_remove(dev, nvdev);
2586rndis_failed:
2587	netvsc_devinfo_put(device_info);
2588devinfo_failed:
2589	free_percpu(net_device_ctx->vf_stats);
2590no_stats:
2591	hv_set_drvdata(dev, NULL);
2592	free_netdev(net);
2593no_net:
2594	return ret;
2595}
2596
2597static int netvsc_remove(struct hv_device *dev)
2598{
 
2599	struct net_device_context *ndev_ctx;
2600	struct net_device *vf_netdev, *net;
2601	struct netvsc_device *nvdev;
 
 
2602
2603	net = hv_get_drvdata(dev);
2604	if (net == NULL) {
2605		dev_err(&dev->device, "No net device to remove\n");
2606		return 0;
2607	}
2608
 
 
2609	ndev_ctx = netdev_priv(net);
 
 
2610
2611	cancel_delayed_work_sync(&ndev_ctx->dwork);
 
2612
2613	rtnl_lock();
2614	nvdev = rtnl_dereference(ndev_ctx->nvdev);
2615	if (nvdev) {
2616		cancel_work_sync(&nvdev->subchan_work);
2617		netvsc_xdp_set(net, NULL, NULL, nvdev);
2618	}
2619
2620	/*
2621	 * Call to the vsc driver to let it know that the device is being
2622	 * removed. Also blocks mtu and channel changes.
2623	 */
2624	vf_netdev = rtnl_dereference(ndev_ctx->vf_netdev);
2625	if (vf_netdev)
2626		netvsc_unregister_vf(vf_netdev);
2627
2628	if (nvdev)
2629		rndis_filter_device_remove(dev, nvdev);
2630
2631	unregister_netdevice(net);
2632	list_del(&ndev_ctx->list);
2633
2634	rtnl_unlock();
2635
2636	hv_set_drvdata(dev, NULL);
2637
2638	free_percpu(ndev_ctx->vf_stats);
2639	free_netdev(net);
2640	return 0;
2641}
2642
2643static int netvsc_suspend(struct hv_device *dev)
2644{
2645	struct net_device_context *ndev_ctx;
2646	struct netvsc_device *nvdev;
2647	struct net_device *net;
2648	int ret;
2649
2650	net = hv_get_drvdata(dev);
2651
2652	ndev_ctx = netdev_priv(net);
2653	cancel_delayed_work_sync(&ndev_ctx->dwork);
2654
2655	rtnl_lock();
2656
2657	nvdev = rtnl_dereference(ndev_ctx->nvdev);
2658	if (nvdev == NULL) {
2659		ret = -ENODEV;
2660		goto out;
2661	}
2662
2663	/* Save the current config info */
2664	ndev_ctx->saved_netvsc_dev_info = netvsc_devinfo_get(nvdev);
2665
2666	ret = netvsc_detach(net, nvdev);
2667out:
2668	rtnl_unlock();
2669
2670	return ret;
2671}
2672
2673static int netvsc_resume(struct hv_device *dev)
2674{
2675	struct net_device *net = hv_get_drvdata(dev);
2676	struct net_device_context *net_device_ctx;
2677	struct netvsc_device_info *device_info;
2678	int ret;
2679
2680	rtnl_lock();
2681
2682	net_device_ctx = netdev_priv(net);
2683
2684	/* Reset the data path to the netvsc NIC before re-opening the vmbus
2685	 * channel. Later netvsc_netdev_event() will switch the data path to
2686	 * the VF upon the UP or CHANGE event.
2687	 */
2688	net_device_ctx->data_path_is_vf = false;
2689	device_info = net_device_ctx->saved_netvsc_dev_info;
2690
2691	ret = netvsc_attach(net, device_info);
2692
2693	netvsc_devinfo_put(device_info);
2694	net_device_ctx->saved_netvsc_dev_info = NULL;
2695
2696	rtnl_unlock();
2697
2698	return ret;
2699}
2700static const struct hv_vmbus_device_id id_table[] = {
2701	/* Network guid */
2702	{ HV_NIC_GUID, },
2703	{ },
2704};
2705
2706MODULE_DEVICE_TABLE(vmbus, id_table);
2707
2708/* The one and only one */
2709static struct  hv_driver netvsc_drv = {
2710	.name = KBUILD_MODNAME,
2711	.id_table = id_table,
2712	.probe = netvsc_probe,
2713	.remove = netvsc_remove,
2714	.suspend = netvsc_suspend,
2715	.resume = netvsc_resume,
2716	.driver = {
2717		.probe_type = PROBE_FORCE_SYNCHRONOUS,
2718	},
2719};
2720
2721/*
2722 * On Hyper-V, every VF interface is matched with a corresponding
2723 * synthetic interface. The synthetic interface is presented first
2724 * to the guest. When the corresponding VF instance is registered,
2725 * we will take care of switching the data path.
2726 */
2727static int netvsc_netdev_event(struct notifier_block *this,
2728			       unsigned long event, void *ptr)
2729{
2730	struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
2731
2732	/* Skip our own events */
2733	if (event_dev->netdev_ops == &device_ops)
2734		return NOTIFY_DONE;
2735
2736	/* Avoid non-Ethernet type devices */
2737	if (event_dev->type != ARPHRD_ETHER)
2738		return NOTIFY_DONE;
2739
2740	/* Avoid Vlan dev with same MAC registering as VF */
2741	if (is_vlan_dev(event_dev))
2742		return NOTIFY_DONE;
2743
2744	/* Avoid Bonding master dev with same MAC registering as VF */
2745	if ((event_dev->priv_flags & IFF_BONDING) &&
2746	    (event_dev->flags & IFF_MASTER))
2747		return NOTIFY_DONE;
2748
2749	switch (event) {
2750	case NETDEV_REGISTER:
2751		return netvsc_register_vf(event_dev);
2752	case NETDEV_UNREGISTER:
2753		return netvsc_unregister_vf(event_dev);
2754	case NETDEV_UP:
2755	case NETDEV_DOWN:
2756	case NETDEV_CHANGE:
2757	case NETDEV_GOING_DOWN:
2758		return netvsc_vf_changed(event_dev, event);
2759	default:
2760		return NOTIFY_DONE;
2761	}
2762}
2763
2764static struct notifier_block netvsc_netdev_notifier = {
2765	.notifier_call = netvsc_netdev_event,
2766};
2767
2768static void __exit netvsc_drv_exit(void)
2769{
2770	unregister_netdevice_notifier(&netvsc_netdev_notifier);
2771	vmbus_driver_unregister(&netvsc_drv);
2772}
2773
2774static int __init netvsc_drv_init(void)
2775{
2776	int ret;
2777
2778	if (ring_size < RING_SIZE_MIN) {
2779		ring_size = RING_SIZE_MIN;
2780		pr_info("Increased ring_size to %u (min allowed)\n",
2781			ring_size);
2782	}
2783	netvsc_ring_bytes = ring_size * PAGE_SIZE;
2784
2785	ret = vmbus_driver_register(&netvsc_drv);
2786	if (ret)
2787		return ret;
2788
2789	register_netdevice_notifier(&netvsc_netdev_notifier);
2790	return 0;
2791}
2792
2793MODULE_LICENSE("GPL");
2794MODULE_DESCRIPTION("Microsoft Hyper-V network driver");
2795
2796module_init(netvsc_drv_init);
2797module_exit(netvsc_drv_exit);