xref: /openbmc/linux/drivers/net/hyperv/netvsc_drv.c (revision d236d361)
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 
43 #define RING_SIZE_MIN 64
44 #define LINKCHANGE_INT (2 * HZ)
45 
46 static int ring_size = 128;
47 module_param(ring_size, int, S_IRUGO);
48 MODULE_PARM_DESC(ring_size, "Ring buffer size (# of pages)");
49 
50 static 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 
55 static int debug = -1;
56 module_param(debug, int, S_IRUGO);
57 MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
58 
59 static void do_set_multicast(struct work_struct *w)
60 {
61 	struct net_device_context *ndevctx =
62 		container_of(w, struct net_device_context, work);
63 	struct hv_device *device_obj = ndevctx->device_ctx;
64 	struct net_device *ndev = hv_get_drvdata(device_obj);
65 	struct netvsc_device *nvdev = rcu_dereference(ndevctx->nvdev);
66 	struct rndis_device *rdev;
67 
68 	if (!nvdev)
69 		return;
70 
71 	rdev = nvdev->extension;
72 	if (rdev == NULL)
73 		return;
74 
75 	if (ndev->flags & IFF_PROMISC)
76 		rndis_filter_set_packet_filter(rdev,
77 			NDIS_PACKET_TYPE_PROMISCUOUS);
78 	else
79 		rndis_filter_set_packet_filter(rdev,
80 			NDIS_PACKET_TYPE_BROADCAST |
81 			NDIS_PACKET_TYPE_ALL_MULTICAST |
82 			NDIS_PACKET_TYPE_DIRECTED);
83 }
84 
85 static void netvsc_set_multicast_list(struct net_device *net)
86 {
87 	struct net_device_context *net_device_ctx = netdev_priv(net);
88 
89 	schedule_work(&net_device_ctx->work);
90 }
91 
92 static int netvsc_open(struct net_device *net)
93 {
94 	struct netvsc_device *nvdev = net_device_to_netvsc_device(net);
95 	struct rndis_device *rdev;
96 	int ret = 0;
97 
98 	netif_carrier_off(net);
99 
100 	/* Open up the device */
101 	ret = rndis_filter_open(nvdev);
102 	if (ret != 0) {
103 		netdev_err(net, "unable to open device (ret %d).\n", ret);
104 		return ret;
105 	}
106 
107 	netif_tx_wake_all_queues(net);
108 
109 	rdev = nvdev->extension;
110 	if (!rdev->link_state)
111 		netif_carrier_on(net);
112 
113 	return ret;
114 }
115 
116 static int netvsc_close(struct net_device *net)
117 {
118 	struct net_device_context *net_device_ctx = netdev_priv(net);
119 	struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
120 	int ret;
121 	u32 aread, awrite, i, msec = 10, retry = 0, retry_max = 20;
122 	struct vmbus_channel *chn;
123 
124 	netif_tx_disable(net);
125 
126 	/* Make sure netvsc_set_multicast_list doesn't re-enable filter! */
127 	cancel_work_sync(&net_device_ctx->work);
128 	ret = rndis_filter_close(nvdev);
129 	if (ret != 0) {
130 		netdev_err(net, "unable to close device (ret %d).\n", ret);
131 		return ret;
132 	}
133 
134 	/* Ensure pending bytes in ring are read */
135 	while (true) {
136 		aread = 0;
137 		for (i = 0; i < nvdev->num_chn; i++) {
138 			chn = nvdev->chan_table[i].channel;
139 			if (!chn)
140 				continue;
141 
142 			hv_get_ringbuffer_availbytes(&chn->inbound, &aread,
143 						     &awrite);
144 
145 			if (aread)
146 				break;
147 
148 			hv_get_ringbuffer_availbytes(&chn->outbound, &aread,
149 						     &awrite);
150 
151 			if (aread)
152 				break;
153 		}
154 
155 		retry++;
156 		if (retry > retry_max || aread == 0)
157 			break;
158 
159 		msleep(msec);
160 
161 		if (msec < 1000)
162 			msec *= 2;
163 	}
164 
165 	if (aread) {
166 		netdev_err(net, "Ring buffer not empty after closing rndis\n");
167 		ret = -ETIMEDOUT;
168 	}
169 
170 	return ret;
171 }
172 
173 static void *init_ppi_data(struct rndis_message *msg, u32 ppi_size,
174 				int pkt_type)
175 {
176 	struct rndis_packet *rndis_pkt;
177 	struct rndis_per_packet_info *ppi;
178 
179 	rndis_pkt = &msg->msg.pkt;
180 	rndis_pkt->data_offset += ppi_size;
181 
182 	ppi = (struct rndis_per_packet_info *)((void *)rndis_pkt +
183 		rndis_pkt->per_pkt_info_offset + rndis_pkt->per_pkt_info_len);
184 
185 	ppi->size = ppi_size;
186 	ppi->type = pkt_type;
187 	ppi->ppi_offset = sizeof(struct rndis_per_packet_info);
188 
189 	rndis_pkt->per_pkt_info_len += ppi_size;
190 
191 	return ppi;
192 }
193 
194 /* Azure hosts don't support non-TCP port numbers in hashing yet. We compute
195  * hash for non-TCP traffic with only IP numbers.
196  */
197 static inline u32 netvsc_get_hash(struct sk_buff *skb, struct sock *sk)
198 {
199 	struct flow_keys flow;
200 	u32 hash;
201 	static u32 hashrnd __read_mostly;
202 
203 	net_get_random_once(&hashrnd, sizeof(hashrnd));
204 
205 	if (!skb_flow_dissect_flow_keys(skb, &flow, 0))
206 		return 0;
207 
208 	if (flow.basic.ip_proto == IPPROTO_TCP) {
209 		return skb_get_hash(skb);
210 	} else {
211 		if (flow.basic.n_proto == htons(ETH_P_IP))
212 			hash = jhash2((u32 *)&flow.addrs.v4addrs, 2, hashrnd);
213 		else if (flow.basic.n_proto == htons(ETH_P_IPV6))
214 			hash = jhash2((u32 *)&flow.addrs.v6addrs, 8, hashrnd);
215 		else
216 			hash = 0;
217 
218 		skb_set_hash(skb, hash, PKT_HASH_TYPE_L3);
219 	}
220 
221 	return hash;
222 }
223 
224 static inline int netvsc_get_tx_queue(struct net_device *ndev,
225 				      struct sk_buff *skb, int old_idx)
226 {
227 	const struct net_device_context *ndc = netdev_priv(ndev);
228 	struct sock *sk = skb->sk;
229 	int q_idx;
230 
231 	q_idx = ndc->tx_send_table[netvsc_get_hash(skb, sk) &
232 				   (VRSS_SEND_TAB_SIZE - 1)];
233 
234 	/* If queue index changed record the new value */
235 	if (q_idx != old_idx &&
236 	    sk && sk_fullsock(sk) && rcu_access_pointer(sk->sk_dst_cache))
237 		sk_tx_queue_set(sk, q_idx);
238 
239 	return q_idx;
240 }
241 
242 /*
243  * Select queue for transmit.
244  *
245  * If a valid queue has already been assigned, then use that.
246  * Otherwise compute tx queue based on hash and the send table.
247  *
248  * This is basically similar to default (__netdev_pick_tx) with the added step
249  * of using the host send_table when no other queue has been assigned.
250  *
251  * TODO support XPS - but get_xps_queue not exported
252  */
253 static u16 netvsc_select_queue(struct net_device *ndev, struct sk_buff *skb,
254 			void *accel_priv, select_queue_fallback_t fallback)
255 {
256 	unsigned int num_tx_queues = ndev->real_num_tx_queues;
257 	int q_idx = sk_tx_queue_get(skb->sk);
258 
259 	if (q_idx < 0 || skb->ooo_okay) {
260 		/* If forwarding a packet, we use the recorded queue when
261 		 * available for better cache locality.
262 		 */
263 		if (skb_rx_queue_recorded(skb))
264 			q_idx = skb_get_rx_queue(skb);
265 		else
266 			q_idx = netvsc_get_tx_queue(ndev, skb, q_idx);
267 	}
268 
269 	while (unlikely(q_idx >= num_tx_queues))
270 		q_idx -= num_tx_queues;
271 
272 	return q_idx;
273 }
274 
275 static u32 fill_pg_buf(struct page *page, u32 offset, u32 len,
276 			struct hv_page_buffer *pb)
277 {
278 	int j = 0;
279 
280 	/* Deal with compund pages by ignoring unused part
281 	 * of the page.
282 	 */
283 	page += (offset >> PAGE_SHIFT);
284 	offset &= ~PAGE_MASK;
285 
286 	while (len > 0) {
287 		unsigned long bytes;
288 
289 		bytes = PAGE_SIZE - offset;
290 		if (bytes > len)
291 			bytes = len;
292 		pb[j].pfn = page_to_pfn(page);
293 		pb[j].offset = offset;
294 		pb[j].len = bytes;
295 
296 		offset += bytes;
297 		len -= bytes;
298 
299 		if (offset == PAGE_SIZE && len) {
300 			page++;
301 			offset = 0;
302 			j++;
303 		}
304 	}
305 
306 	return j + 1;
307 }
308 
309 static u32 init_page_array(void *hdr, u32 len, struct sk_buff *skb,
310 			   struct hv_netvsc_packet *packet,
311 			   struct hv_page_buffer **page_buf)
312 {
313 	struct hv_page_buffer *pb = *page_buf;
314 	u32 slots_used = 0;
315 	char *data = skb->data;
316 	int frags = skb_shinfo(skb)->nr_frags;
317 	int i;
318 
319 	/* The packet is laid out thus:
320 	 * 1. hdr: RNDIS header and PPI
321 	 * 2. skb linear data
322 	 * 3. skb fragment data
323 	 */
324 	if (hdr != NULL)
325 		slots_used += fill_pg_buf(virt_to_page(hdr),
326 					offset_in_page(hdr),
327 					len, &pb[slots_used]);
328 
329 	packet->rmsg_size = len;
330 	packet->rmsg_pgcnt = slots_used;
331 
332 	slots_used += fill_pg_buf(virt_to_page(data),
333 				offset_in_page(data),
334 				skb_headlen(skb), &pb[slots_used]);
335 
336 	for (i = 0; i < frags; i++) {
337 		skb_frag_t *frag = skb_shinfo(skb)->frags + i;
338 
339 		slots_used += fill_pg_buf(skb_frag_page(frag),
340 					frag->page_offset,
341 					skb_frag_size(frag), &pb[slots_used]);
342 	}
343 	return slots_used;
344 }
345 
346 static int count_skb_frag_slots(struct sk_buff *skb)
347 {
348 	int i, frags = skb_shinfo(skb)->nr_frags;
349 	int pages = 0;
350 
351 	for (i = 0; i < frags; i++) {
352 		skb_frag_t *frag = skb_shinfo(skb)->frags + i;
353 		unsigned long size = skb_frag_size(frag);
354 		unsigned long offset = frag->page_offset;
355 
356 		/* Skip unused frames from start of page */
357 		offset &= ~PAGE_MASK;
358 		pages += PFN_UP(offset + size);
359 	}
360 	return pages;
361 }
362 
363 static int netvsc_get_slots(struct sk_buff *skb)
364 {
365 	char *data = skb->data;
366 	unsigned int offset = offset_in_page(data);
367 	unsigned int len = skb_headlen(skb);
368 	int slots;
369 	int frag_slots;
370 
371 	slots = DIV_ROUND_UP(offset + len, PAGE_SIZE);
372 	frag_slots = count_skb_frag_slots(skb);
373 	return slots + frag_slots;
374 }
375 
376 static u32 net_checksum_info(struct sk_buff *skb)
377 {
378 	if (skb->protocol == htons(ETH_P_IP)) {
379 		struct iphdr *ip = ip_hdr(skb);
380 
381 		if (ip->protocol == IPPROTO_TCP)
382 			return TRANSPORT_INFO_IPV4_TCP;
383 		else if (ip->protocol == IPPROTO_UDP)
384 			return TRANSPORT_INFO_IPV4_UDP;
385 	} else {
386 		struct ipv6hdr *ip6 = ipv6_hdr(skb);
387 
388 		if (ip6->nexthdr == IPPROTO_TCP)
389 			return TRANSPORT_INFO_IPV6_TCP;
390 		else if (ipv6_hdr(skb)->nexthdr == IPPROTO_UDP)
391 			return TRANSPORT_INFO_IPV6_UDP;
392 	}
393 
394 	return TRANSPORT_INFO_NOT_IP;
395 }
396 
397 static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
398 {
399 	struct net_device_context *net_device_ctx = netdev_priv(net);
400 	struct hv_netvsc_packet *packet = NULL;
401 	int ret;
402 	unsigned int num_data_pgs;
403 	struct rndis_message *rndis_msg;
404 	struct rndis_packet *rndis_pkt;
405 	u32 rndis_msg_size;
406 	struct rndis_per_packet_info *ppi;
407 	u32 hash;
408 	struct hv_page_buffer page_buf[MAX_PAGE_BUFFER_COUNT];
409 	struct hv_page_buffer *pb = page_buf;
410 
411 	/* We will atmost need two pages to describe the rndis
412 	 * header. We can only transmit MAX_PAGE_BUFFER_COUNT number
413 	 * of pages in a single packet. If skb is scattered around
414 	 * more pages we try linearizing it.
415 	 */
416 
417 	num_data_pgs = netvsc_get_slots(skb) + 2;
418 
419 	if (unlikely(num_data_pgs > MAX_PAGE_BUFFER_COUNT)) {
420 		++net_device_ctx->eth_stats.tx_scattered;
421 
422 		if (skb_linearize(skb))
423 			goto no_memory;
424 
425 		num_data_pgs = netvsc_get_slots(skb) + 2;
426 		if (num_data_pgs > MAX_PAGE_BUFFER_COUNT) {
427 			++net_device_ctx->eth_stats.tx_too_big;
428 			goto drop;
429 		}
430 	}
431 
432 	/*
433 	 * Place the rndis header in the skb head room and
434 	 * the skb->cb will be used for hv_netvsc_packet
435 	 * structure.
436 	 */
437 	ret = skb_cow_head(skb, RNDIS_AND_PPI_SIZE);
438 	if (ret)
439 		goto no_memory;
440 
441 	/* Use the skb control buffer for building up the packet */
442 	BUILD_BUG_ON(sizeof(struct hv_netvsc_packet) >
443 			FIELD_SIZEOF(struct sk_buff, cb));
444 	packet = (struct hv_netvsc_packet *)skb->cb;
445 
446 	packet->q_idx = skb_get_queue_mapping(skb);
447 
448 	packet->total_data_buflen = skb->len;
449 	packet->total_bytes = skb->len;
450 	packet->total_packets = 1;
451 
452 	rndis_msg = (struct rndis_message *)skb->head;
453 
454 	memset(rndis_msg, 0, RNDIS_AND_PPI_SIZE);
455 
456 	/* Add the rndis header */
457 	rndis_msg->ndis_msg_type = RNDIS_MSG_PACKET;
458 	rndis_msg->msg_len = packet->total_data_buflen;
459 	rndis_pkt = &rndis_msg->msg.pkt;
460 	rndis_pkt->data_offset = sizeof(struct rndis_packet);
461 	rndis_pkt->data_len = packet->total_data_buflen;
462 	rndis_pkt->per_pkt_info_offset = sizeof(struct rndis_packet);
463 
464 	rndis_msg_size = RNDIS_MESSAGE_SIZE(struct rndis_packet);
465 
466 	hash = skb_get_hash_raw(skb);
467 	if (hash != 0 && net->real_num_tx_queues > 1) {
468 		rndis_msg_size += NDIS_HASH_PPI_SIZE;
469 		ppi = init_ppi_data(rndis_msg, NDIS_HASH_PPI_SIZE,
470 				    NBL_HASH_VALUE);
471 		*(u32 *)((void *)ppi + ppi->ppi_offset) = hash;
472 	}
473 
474 	if (skb_vlan_tag_present(skb)) {
475 		struct ndis_pkt_8021q_info *vlan;
476 
477 		rndis_msg_size += NDIS_VLAN_PPI_SIZE;
478 		ppi = init_ppi_data(rndis_msg, NDIS_VLAN_PPI_SIZE,
479 					IEEE_8021Q_INFO);
480 		vlan = (struct ndis_pkt_8021q_info *)((void *)ppi +
481 						ppi->ppi_offset);
482 		vlan->vlanid = skb->vlan_tci & VLAN_VID_MASK;
483 		vlan->pri = (skb->vlan_tci & VLAN_PRIO_MASK) >>
484 				VLAN_PRIO_SHIFT;
485 	}
486 
487 	if (skb_is_gso(skb)) {
488 		struct ndis_tcp_lso_info *lso_info;
489 
490 		rndis_msg_size += NDIS_LSO_PPI_SIZE;
491 		ppi = init_ppi_data(rndis_msg, NDIS_LSO_PPI_SIZE,
492 				    TCP_LARGESEND_PKTINFO);
493 
494 		lso_info = (struct ndis_tcp_lso_info *)((void *)ppi +
495 							ppi->ppi_offset);
496 
497 		lso_info->lso_v2_transmit.type = NDIS_TCP_LARGE_SEND_OFFLOAD_V2_TYPE;
498 		if (skb->protocol == htons(ETH_P_IP)) {
499 			lso_info->lso_v2_transmit.ip_version =
500 				NDIS_TCP_LARGE_SEND_OFFLOAD_IPV4;
501 			ip_hdr(skb)->tot_len = 0;
502 			ip_hdr(skb)->check = 0;
503 			tcp_hdr(skb)->check =
504 				~csum_tcpudp_magic(ip_hdr(skb)->saddr,
505 						   ip_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
506 		} else {
507 			lso_info->lso_v2_transmit.ip_version =
508 				NDIS_TCP_LARGE_SEND_OFFLOAD_IPV6;
509 			ipv6_hdr(skb)->payload_len = 0;
510 			tcp_hdr(skb)->check =
511 				~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
512 						 &ipv6_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
513 		}
514 		lso_info->lso_v2_transmit.tcp_header_offset = skb_transport_offset(skb);
515 		lso_info->lso_v2_transmit.mss = skb_shinfo(skb)->gso_size;
516 	} else if (skb->ip_summed == CHECKSUM_PARTIAL) {
517 		if (net_checksum_info(skb) & net_device_ctx->tx_checksum_mask) {
518 			struct ndis_tcp_ip_checksum_info *csum_info;
519 
520 			rndis_msg_size += NDIS_CSUM_PPI_SIZE;
521 			ppi = init_ppi_data(rndis_msg, NDIS_CSUM_PPI_SIZE,
522 					    TCPIP_CHKSUM_PKTINFO);
523 
524 			csum_info = (struct ndis_tcp_ip_checksum_info *)((void *)ppi +
525 									 ppi->ppi_offset);
526 
527 			csum_info->transmit.tcp_header_offset = skb_transport_offset(skb);
528 
529 			if (skb->protocol == htons(ETH_P_IP)) {
530 				csum_info->transmit.is_ipv4 = 1;
531 
532 				if (ip_hdr(skb)->protocol == IPPROTO_TCP)
533 					csum_info->transmit.tcp_checksum = 1;
534 				else
535 					csum_info->transmit.udp_checksum = 1;
536 			} else {
537 				csum_info->transmit.is_ipv6 = 1;
538 
539 				if (ipv6_hdr(skb)->nexthdr == IPPROTO_TCP)
540 					csum_info->transmit.tcp_checksum = 1;
541 				else
542 					csum_info->transmit.udp_checksum = 1;
543 			}
544 		} else {
545 			/* Can't do offload of this type of checksum */
546 			if (skb_checksum_help(skb))
547 				goto drop;
548 		}
549 	}
550 
551 	/* Start filling in the page buffers with the rndis hdr */
552 	rndis_msg->msg_len += rndis_msg_size;
553 	packet->total_data_buflen = rndis_msg->msg_len;
554 	packet->page_buf_cnt = init_page_array(rndis_msg, rndis_msg_size,
555 					       skb, packet, &pb);
556 
557 	/* timestamp packet in software */
558 	skb_tx_timestamp(skb);
559 	ret = netvsc_send(net_device_ctx->device_ctx, packet,
560 			  rndis_msg, &pb, skb);
561 	if (likely(ret == 0))
562 		return NETDEV_TX_OK;
563 
564 	if (ret == -EAGAIN) {
565 		++net_device_ctx->eth_stats.tx_busy;
566 		return NETDEV_TX_BUSY;
567 	}
568 
569 	if (ret == -ENOSPC)
570 		++net_device_ctx->eth_stats.tx_no_space;
571 
572 drop:
573 	dev_kfree_skb_any(skb);
574 	net->stats.tx_dropped++;
575 
576 	return NETDEV_TX_OK;
577 
578 no_memory:
579 	++net_device_ctx->eth_stats.tx_no_memory;
580 	goto drop;
581 }
582 /*
583  * netvsc_linkstatus_callback - Link up/down notification
584  */
585 void netvsc_linkstatus_callback(struct hv_device *device_obj,
586 				struct rndis_message *resp)
587 {
588 	struct rndis_indicate_status *indicate = &resp->msg.indicate_status;
589 	struct net_device *net;
590 	struct net_device_context *ndev_ctx;
591 	struct netvsc_reconfig *event;
592 	unsigned long flags;
593 
594 	net = hv_get_drvdata(device_obj);
595 
596 	if (!net)
597 		return;
598 
599 	ndev_ctx = netdev_priv(net);
600 
601 	/* Update the physical link speed when changing to another vSwitch */
602 	if (indicate->status == RNDIS_STATUS_LINK_SPEED_CHANGE) {
603 		u32 speed;
604 
605 		speed = *(u32 *)((void *)indicate + indicate->
606 				 status_buf_offset) / 10000;
607 		ndev_ctx->speed = speed;
608 		return;
609 	}
610 
611 	/* Handle these link change statuses below */
612 	if (indicate->status != RNDIS_STATUS_NETWORK_CHANGE &&
613 	    indicate->status != RNDIS_STATUS_MEDIA_CONNECT &&
614 	    indicate->status != RNDIS_STATUS_MEDIA_DISCONNECT)
615 		return;
616 
617 	if (net->reg_state != NETREG_REGISTERED)
618 		return;
619 
620 	event = kzalloc(sizeof(*event), GFP_ATOMIC);
621 	if (!event)
622 		return;
623 	event->event = indicate->status;
624 
625 	spin_lock_irqsave(&ndev_ctx->lock, flags);
626 	list_add_tail(&event->list, &ndev_ctx->reconfig_events);
627 	spin_unlock_irqrestore(&ndev_ctx->lock, flags);
628 
629 	schedule_delayed_work(&ndev_ctx->dwork, 0);
630 }
631 
632 static struct sk_buff *netvsc_alloc_recv_skb(struct net_device *net,
633 					     struct napi_struct *napi,
634 					     const struct ndis_tcp_ip_checksum_info *csum_info,
635 					     const struct ndis_pkt_8021q_info *vlan,
636 					     void *data, u32 buflen)
637 {
638 	struct sk_buff *skb;
639 
640 	skb = napi_alloc_skb(napi, buflen);
641 	if (!skb)
642 		return skb;
643 
644 	/*
645 	 * Copy to skb. This copy is needed here since the memory pointed by
646 	 * hv_netvsc_packet cannot be deallocated
647 	 */
648 	memcpy(skb_put(skb, buflen), data, buflen);
649 
650 	skb->protocol = eth_type_trans(skb, net);
651 
652 	/* skb is already created with CHECKSUM_NONE */
653 	skb_checksum_none_assert(skb);
654 
655 	/*
656 	 * In Linux, the IP checksum is always checked.
657 	 * Do L4 checksum offload if enabled and present.
658 	 */
659 	if (csum_info && (net->features & NETIF_F_RXCSUM)) {
660 		if (csum_info->receive.tcp_checksum_succeeded ||
661 		    csum_info->receive.udp_checksum_succeeded)
662 			skb->ip_summed = CHECKSUM_UNNECESSARY;
663 	}
664 
665 	if (vlan) {
666 		u16 vlan_tci = vlan->vlanid | (vlan->pri << VLAN_PRIO_SHIFT);
667 
668 		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
669 				       vlan_tci);
670 	}
671 
672 	return skb;
673 }
674 
675 /*
676  * netvsc_recv_callback -  Callback when we receive a packet from the
677  * "wire" on the specified device.
678  */
679 int netvsc_recv_callback(struct net_device *net,
680 			 struct vmbus_channel *channel,
681 			 void  *data, u32 len,
682 			 const struct ndis_tcp_ip_checksum_info *csum_info,
683 			 const struct ndis_pkt_8021q_info *vlan)
684 {
685 	struct net_device_context *net_device_ctx = netdev_priv(net);
686 	struct netvsc_device *net_device;
687 	u16 q_idx = channel->offermsg.offer.sub_channel_index;
688 	struct netvsc_channel *nvchan;
689 	struct net_device *vf_netdev;
690 	struct sk_buff *skb;
691 	struct netvsc_stats *rx_stats;
692 
693 	if (net->reg_state != NETREG_REGISTERED)
694 		return NVSP_STAT_FAIL;
695 
696 	/*
697 	 * If necessary, inject this packet into the VF interface.
698 	 * On Hyper-V, multicast and brodcast packets are only delivered
699 	 * to the synthetic interface (after subjecting these to
700 	 * policy filters on the host). Deliver these via the VF
701 	 * interface in the guest.
702 	 */
703 	rcu_read_lock();
704 	net_device = rcu_dereference(net_device_ctx->nvdev);
705 	if (unlikely(!net_device))
706 		goto drop;
707 
708 	nvchan = &net_device->chan_table[q_idx];
709 	vf_netdev = rcu_dereference(net_device_ctx->vf_netdev);
710 	if (vf_netdev && (vf_netdev->flags & IFF_UP))
711 		net = vf_netdev;
712 
713 	/* Allocate a skb - TODO direct I/O to pages? */
714 	skb = netvsc_alloc_recv_skb(net, &nvchan->napi,
715 				    csum_info, vlan, data, len);
716 	if (unlikely(!skb)) {
717 drop:
718 		++net->stats.rx_dropped;
719 		rcu_read_unlock();
720 		return NVSP_STAT_FAIL;
721 	}
722 
723 	if (net != vf_netdev)
724 		skb_record_rx_queue(skb, q_idx);
725 
726 	/*
727 	 * Even if injecting the packet, record the statistics
728 	 * on the synthetic device because modifying the VF device
729 	 * statistics will not work correctly.
730 	 */
731 	rx_stats = &nvchan->rx_stats;
732 	u64_stats_update_begin(&rx_stats->syncp);
733 	rx_stats->packets++;
734 	rx_stats->bytes += len;
735 
736 	if (skb->pkt_type == PACKET_BROADCAST)
737 		++rx_stats->broadcast;
738 	else if (skb->pkt_type == PACKET_MULTICAST)
739 		++rx_stats->multicast;
740 	u64_stats_update_end(&rx_stats->syncp);
741 
742 	napi_gro_receive(&nvchan->napi, skb);
743 	rcu_read_unlock();
744 
745 	return 0;
746 }
747 
748 static void netvsc_get_drvinfo(struct net_device *net,
749 			       struct ethtool_drvinfo *info)
750 {
751 	strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
752 	strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
753 }
754 
755 static void netvsc_get_channels(struct net_device *net,
756 				struct ethtool_channels *channel)
757 {
758 	struct net_device_context *net_device_ctx = netdev_priv(net);
759 	struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
760 
761 	if (nvdev) {
762 		channel->max_combined	= nvdev->max_chn;
763 		channel->combined_count = nvdev->num_chn;
764 	}
765 }
766 
767 static int netvsc_set_queues(struct net_device *net, struct hv_device *dev,
768 			     u32 num_chn)
769 {
770 	struct netvsc_device_info device_info;
771 	int ret;
772 
773 	memset(&device_info, 0, sizeof(device_info));
774 	device_info.num_chn = num_chn;
775 	device_info.ring_size = ring_size;
776 	device_info.max_num_vrss_chns = num_chn;
777 
778 	ret = rndis_filter_device_add(dev, &device_info);
779 	if (ret)
780 		return ret;
781 
782 	ret = netif_set_real_num_tx_queues(net, num_chn);
783 	if (ret)
784 		return ret;
785 
786 	ret = netif_set_real_num_rx_queues(net, num_chn);
787 
788 	return ret;
789 }
790 
791 static int netvsc_set_channels(struct net_device *net,
792 			       struct ethtool_channels *channels)
793 {
794 	struct net_device_context *net_device_ctx = netdev_priv(net);
795 	struct hv_device *dev = net_device_ctx->device_ctx;
796 	struct netvsc_device *nvdev = rtnl_dereference(net_device_ctx->nvdev);
797 	unsigned int count = channels->combined_count;
798 	bool was_running;
799 	int ret;
800 
801 	/* We do not support separate count for rx, tx, or other */
802 	if (count == 0 ||
803 	    channels->rx_count || channels->tx_count || channels->other_count)
804 		return -EINVAL;
805 
806 	if (count > net->num_tx_queues || count > net->num_rx_queues)
807 		return -EINVAL;
808 
809 	if (!nvdev || nvdev->destroy)
810 		return -ENODEV;
811 
812 	if (nvdev->nvsp_version < NVSP_PROTOCOL_VERSION_5)
813 		return -EINVAL;
814 
815 	if (count > nvdev->max_chn)
816 		return -EINVAL;
817 
818 	was_running = netif_running(net);
819 	if (was_running) {
820 		ret = netvsc_close(net);
821 		if (ret)
822 			return ret;
823 	}
824 
825 	rndis_filter_device_remove(dev, nvdev);
826 
827 	ret = netvsc_set_queues(net, dev, count);
828 	if (ret == 0)
829 		nvdev->num_chn = count;
830 	else
831 		netvsc_set_queues(net, dev, nvdev->num_chn);
832 
833 	if (was_running)
834 		ret = netvsc_open(net);
835 
836 	/* We may have missed link change notifications */
837 	schedule_delayed_work(&net_device_ctx->dwork, 0);
838 
839 	return ret;
840 }
841 
842 static bool
843 netvsc_validate_ethtool_ss_cmd(const struct ethtool_link_ksettings *cmd)
844 {
845 	struct ethtool_link_ksettings diff1 = *cmd;
846 	struct ethtool_link_ksettings diff2 = {};
847 
848 	diff1.base.speed = 0;
849 	diff1.base.duplex = 0;
850 	/* advertising and cmd are usually set */
851 	ethtool_link_ksettings_zero_link_mode(&diff1, advertising);
852 	diff1.base.cmd = 0;
853 	/* We set port to PORT_OTHER */
854 	diff2.base.port = PORT_OTHER;
855 
856 	return !memcmp(&diff1, &diff2, sizeof(diff1));
857 }
858 
859 static void netvsc_init_settings(struct net_device *dev)
860 {
861 	struct net_device_context *ndc = netdev_priv(dev);
862 
863 	ndc->speed = SPEED_UNKNOWN;
864 	ndc->duplex = DUPLEX_FULL;
865 }
866 
867 static int netvsc_get_link_ksettings(struct net_device *dev,
868 				     struct ethtool_link_ksettings *cmd)
869 {
870 	struct net_device_context *ndc = netdev_priv(dev);
871 
872 	cmd->base.speed = ndc->speed;
873 	cmd->base.duplex = ndc->duplex;
874 	cmd->base.port = PORT_OTHER;
875 
876 	return 0;
877 }
878 
879 static int netvsc_set_link_ksettings(struct net_device *dev,
880 				     const struct ethtool_link_ksettings *cmd)
881 {
882 	struct net_device_context *ndc = netdev_priv(dev);
883 	u32 speed;
884 
885 	speed = cmd->base.speed;
886 	if (!ethtool_validate_speed(speed) ||
887 	    !ethtool_validate_duplex(cmd->base.duplex) ||
888 	    !netvsc_validate_ethtool_ss_cmd(cmd))
889 		return -EINVAL;
890 
891 	ndc->speed = speed;
892 	ndc->duplex = cmd->base.duplex;
893 
894 	return 0;
895 }
896 
897 static int netvsc_change_mtu(struct net_device *ndev, int mtu)
898 {
899 	struct net_device_context *ndevctx = netdev_priv(ndev);
900 	struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev);
901 	struct hv_device *hdev = ndevctx->device_ctx;
902 	struct netvsc_device_info device_info;
903 	bool was_running;
904 	int ret = 0;
905 
906 	if (!nvdev || nvdev->destroy)
907 		return -ENODEV;
908 
909 	was_running = netif_running(ndev);
910 	if (was_running) {
911 		ret = netvsc_close(ndev);
912 		if (ret)
913 			return ret;
914 	}
915 
916 	memset(&device_info, 0, sizeof(device_info));
917 	device_info.ring_size = ring_size;
918 	device_info.num_chn = nvdev->num_chn;
919 	device_info.max_num_vrss_chns = nvdev->num_chn;
920 
921 	rndis_filter_device_remove(hdev, nvdev);
922 
923 	/* 'nvdev' has been freed in rndis_filter_device_remove() ->
924 	 * netvsc_device_remove () -> free_netvsc_device().
925 	 * We mustn't access it before it's re-created in
926 	 * rndis_filter_device_add() -> netvsc_device_add().
927 	 */
928 
929 	ndev->mtu = mtu;
930 
931 	rndis_filter_device_add(hdev, &device_info);
932 
933 	if (was_running)
934 		ret = netvsc_open(ndev);
935 
936 	/* We may have missed link change notifications */
937 	schedule_delayed_work(&ndevctx->dwork, 0);
938 
939 	return ret;
940 }
941 
942 static void netvsc_get_stats64(struct net_device *net,
943 			       struct rtnl_link_stats64 *t)
944 {
945 	struct net_device_context *ndev_ctx = netdev_priv(net);
946 	struct netvsc_device *nvdev = rcu_dereference_rtnl(ndev_ctx->nvdev);
947 	int i;
948 
949 	if (!nvdev)
950 		return;
951 
952 	for (i = 0; i < nvdev->num_chn; i++) {
953 		const struct netvsc_channel *nvchan = &nvdev->chan_table[i];
954 		const struct netvsc_stats *stats;
955 		u64 packets, bytes, multicast;
956 		unsigned int start;
957 
958 		stats = &nvchan->tx_stats;
959 		do {
960 			start = u64_stats_fetch_begin_irq(&stats->syncp);
961 			packets = stats->packets;
962 			bytes = stats->bytes;
963 		} while (u64_stats_fetch_retry_irq(&stats->syncp, start));
964 
965 		t->tx_bytes	+= bytes;
966 		t->tx_packets	+= packets;
967 
968 		stats = &nvchan->rx_stats;
969 		do {
970 			start = u64_stats_fetch_begin_irq(&stats->syncp);
971 			packets = stats->packets;
972 			bytes = stats->bytes;
973 			multicast = stats->multicast + stats->broadcast;
974 		} while (u64_stats_fetch_retry_irq(&stats->syncp, start));
975 
976 		t->rx_bytes	+= bytes;
977 		t->rx_packets	+= packets;
978 		t->multicast	+= multicast;
979 	}
980 
981 	t->tx_dropped	= net->stats.tx_dropped;
982 	t->tx_errors	= net->stats.tx_errors;
983 
984 	t->rx_dropped	= net->stats.rx_dropped;
985 	t->rx_errors	= net->stats.rx_errors;
986 }
987 
988 static int netvsc_set_mac_addr(struct net_device *ndev, void *p)
989 {
990 	struct sockaddr *addr = p;
991 	char save_adr[ETH_ALEN];
992 	unsigned char save_aatype;
993 	int err;
994 
995 	memcpy(save_adr, ndev->dev_addr, ETH_ALEN);
996 	save_aatype = ndev->addr_assign_type;
997 
998 	err = eth_mac_addr(ndev, p);
999 	if (err != 0)
1000 		return err;
1001 
1002 	err = rndis_filter_set_device_mac(ndev, addr->sa_data);
1003 	if (err != 0) {
1004 		/* roll back to saved MAC */
1005 		memcpy(ndev->dev_addr, save_adr, ETH_ALEN);
1006 		ndev->addr_assign_type = save_aatype;
1007 	}
1008 
1009 	return err;
1010 }
1011 
1012 static const struct {
1013 	char name[ETH_GSTRING_LEN];
1014 	u16 offset;
1015 } netvsc_stats[] = {
1016 	{ "tx_scattered", offsetof(struct netvsc_ethtool_stats, tx_scattered) },
1017 	{ "tx_no_memory",  offsetof(struct netvsc_ethtool_stats, tx_no_memory) },
1018 	{ "tx_no_space",  offsetof(struct netvsc_ethtool_stats, tx_no_space) },
1019 	{ "tx_too_big",	  offsetof(struct netvsc_ethtool_stats, tx_too_big) },
1020 	{ "tx_busy",	  offsetof(struct netvsc_ethtool_stats, tx_busy) },
1021 };
1022 
1023 #define NETVSC_GLOBAL_STATS_LEN	ARRAY_SIZE(netvsc_stats)
1024 
1025 /* 4 statistics per queue (rx/tx packets/bytes) */
1026 #define NETVSC_QUEUE_STATS_LEN(dev) ((dev)->num_chn * 4)
1027 
1028 static int netvsc_get_sset_count(struct net_device *dev, int string_set)
1029 {
1030 	struct net_device_context *ndc = netdev_priv(dev);
1031 	struct netvsc_device *nvdev = rcu_dereference(ndc->nvdev);
1032 
1033 	if (!nvdev)
1034 		return -ENODEV;
1035 
1036 	switch (string_set) {
1037 	case ETH_SS_STATS:
1038 		return NETVSC_GLOBAL_STATS_LEN + NETVSC_QUEUE_STATS_LEN(nvdev);
1039 	default:
1040 		return -EINVAL;
1041 	}
1042 }
1043 
1044 static void netvsc_get_ethtool_stats(struct net_device *dev,
1045 				     struct ethtool_stats *stats, u64 *data)
1046 {
1047 	struct net_device_context *ndc = netdev_priv(dev);
1048 	struct netvsc_device *nvdev = rcu_dereference(ndc->nvdev);
1049 	const void *nds = &ndc->eth_stats;
1050 	const struct netvsc_stats *qstats;
1051 	unsigned int start;
1052 	u64 packets, bytes;
1053 	int i, j;
1054 
1055 	if (!nvdev)
1056 		return;
1057 
1058 	for (i = 0; i < NETVSC_GLOBAL_STATS_LEN; i++)
1059 		data[i] = *(unsigned long *)(nds + netvsc_stats[i].offset);
1060 
1061 	for (j = 0; j < nvdev->num_chn; j++) {
1062 		qstats = &nvdev->chan_table[j].tx_stats;
1063 
1064 		do {
1065 			start = u64_stats_fetch_begin_irq(&qstats->syncp);
1066 			packets = qstats->packets;
1067 			bytes = qstats->bytes;
1068 		} while (u64_stats_fetch_retry_irq(&qstats->syncp, start));
1069 		data[i++] = packets;
1070 		data[i++] = bytes;
1071 
1072 		qstats = &nvdev->chan_table[j].rx_stats;
1073 		do {
1074 			start = u64_stats_fetch_begin_irq(&qstats->syncp);
1075 			packets = qstats->packets;
1076 			bytes = qstats->bytes;
1077 		} while (u64_stats_fetch_retry_irq(&qstats->syncp, start));
1078 		data[i++] = packets;
1079 		data[i++] = bytes;
1080 	}
1081 }
1082 
1083 static void netvsc_get_strings(struct net_device *dev, u32 stringset, u8 *data)
1084 {
1085 	struct net_device_context *ndc = netdev_priv(dev);
1086 	struct netvsc_device *nvdev = rcu_dereference(ndc->nvdev);
1087 	u8 *p = data;
1088 	int i;
1089 
1090 	if (!nvdev)
1091 		return;
1092 
1093 	switch (stringset) {
1094 	case ETH_SS_STATS:
1095 		for (i = 0; i < ARRAY_SIZE(netvsc_stats); i++)
1096 			memcpy(p + i * ETH_GSTRING_LEN,
1097 			       netvsc_stats[i].name, ETH_GSTRING_LEN);
1098 
1099 		p += i * ETH_GSTRING_LEN;
1100 		for (i = 0; i < nvdev->num_chn; i++) {
1101 			sprintf(p, "tx_queue_%u_packets", i);
1102 			p += ETH_GSTRING_LEN;
1103 			sprintf(p, "tx_queue_%u_bytes", i);
1104 			p += ETH_GSTRING_LEN;
1105 			sprintf(p, "rx_queue_%u_packets", i);
1106 			p += ETH_GSTRING_LEN;
1107 			sprintf(p, "rx_queue_%u_bytes", i);
1108 			p += ETH_GSTRING_LEN;
1109 		}
1110 
1111 		break;
1112 	}
1113 }
1114 
1115 static int
1116 netvsc_get_rss_hash_opts(struct netvsc_device *nvdev,
1117 			 struct ethtool_rxnfc *info)
1118 {
1119 	info->data = RXH_IP_SRC | RXH_IP_DST;
1120 
1121 	switch (info->flow_type) {
1122 	case TCP_V4_FLOW:
1123 	case TCP_V6_FLOW:
1124 		info->data |= RXH_L4_B_0_1 | RXH_L4_B_2_3;
1125 		/* fallthrough */
1126 	case UDP_V4_FLOW:
1127 	case UDP_V6_FLOW:
1128 	case IPV4_FLOW:
1129 	case IPV6_FLOW:
1130 		break;
1131 	default:
1132 		info->data = 0;
1133 		break;
1134 	}
1135 
1136 	return 0;
1137 }
1138 
1139 static int
1140 netvsc_get_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info,
1141 		 u32 *rules)
1142 {
1143 	struct net_device_context *ndc = netdev_priv(dev);
1144 	struct netvsc_device *nvdev = rcu_dereference(ndc->nvdev);
1145 
1146 	if (!nvdev)
1147 		return -ENODEV;
1148 
1149 	switch (info->cmd) {
1150 	case ETHTOOL_GRXRINGS:
1151 		info->data = nvdev->num_chn;
1152 		return 0;
1153 
1154 	case ETHTOOL_GRXFH:
1155 		return netvsc_get_rss_hash_opts(nvdev, info);
1156 	}
1157 	return -EOPNOTSUPP;
1158 }
1159 
1160 #ifdef CONFIG_NET_POLL_CONTROLLER
1161 static void netvsc_poll_controller(struct net_device *net)
1162 {
1163 	/* As netvsc_start_xmit() works synchronous we don't have to
1164 	 * trigger anything here.
1165 	 */
1166 }
1167 #endif
1168 
1169 static u32 netvsc_get_rxfh_key_size(struct net_device *dev)
1170 {
1171 	return NETVSC_HASH_KEYLEN;
1172 }
1173 
1174 static u32 netvsc_rss_indir_size(struct net_device *dev)
1175 {
1176 	return ITAB_NUM;
1177 }
1178 
1179 static int netvsc_get_rxfh(struct net_device *dev, u32 *indir, u8 *key,
1180 			   u8 *hfunc)
1181 {
1182 	struct net_device_context *ndc = netdev_priv(dev);
1183 	struct netvsc_device *ndev = rcu_dereference(ndc->nvdev);
1184 	struct rndis_device *rndis_dev;
1185 	int i;
1186 
1187 	if (!ndev)
1188 		return -ENODEV;
1189 
1190 	if (hfunc)
1191 		*hfunc = ETH_RSS_HASH_TOP;	/* Toeplitz */
1192 
1193 	rndis_dev = ndev->extension;
1194 	if (indir) {
1195 		for (i = 0; i < ITAB_NUM; i++)
1196 			indir[i] = rndis_dev->ind_table[i];
1197 	}
1198 
1199 	if (key)
1200 		memcpy(key, rndis_dev->rss_key, NETVSC_HASH_KEYLEN);
1201 
1202 	return 0;
1203 }
1204 
1205 static int netvsc_set_rxfh(struct net_device *dev, const u32 *indir,
1206 			   const u8 *key, const u8 hfunc)
1207 {
1208 	struct net_device_context *ndc = netdev_priv(dev);
1209 	struct netvsc_device *ndev = rtnl_dereference(ndc->nvdev);
1210 	struct rndis_device *rndis_dev;
1211 	int i;
1212 
1213 	if (!ndev)
1214 		return -ENODEV;
1215 
1216 	if (hfunc != ETH_RSS_HASH_NO_CHANGE && hfunc != ETH_RSS_HASH_TOP)
1217 		return -EOPNOTSUPP;
1218 
1219 	rndis_dev = ndev->extension;
1220 	if (indir) {
1221 		for (i = 0; i < ITAB_NUM; i++)
1222 			if (indir[i] >= dev->num_rx_queues)
1223 				return -EINVAL;
1224 
1225 		for (i = 0; i < ITAB_NUM; i++)
1226 			rndis_dev->ind_table[i] = indir[i];
1227 	}
1228 
1229 	if (!key) {
1230 		if (!indir)
1231 			return 0;
1232 
1233 		key = rndis_dev->rss_key;
1234 	}
1235 
1236 	return rndis_filter_set_rss_param(rndis_dev, key, ndev->num_chn);
1237 }
1238 
1239 static const struct ethtool_ops ethtool_ops = {
1240 	.get_drvinfo	= netvsc_get_drvinfo,
1241 	.get_link	= ethtool_op_get_link,
1242 	.get_ethtool_stats = netvsc_get_ethtool_stats,
1243 	.get_sset_count = netvsc_get_sset_count,
1244 	.get_strings	= netvsc_get_strings,
1245 	.get_channels   = netvsc_get_channels,
1246 	.set_channels   = netvsc_set_channels,
1247 	.get_ts_info	= ethtool_op_get_ts_info,
1248 	.get_rxnfc	= netvsc_get_rxnfc,
1249 	.get_rxfh_key_size = netvsc_get_rxfh_key_size,
1250 	.get_rxfh_indir_size = netvsc_rss_indir_size,
1251 	.get_rxfh	= netvsc_get_rxfh,
1252 	.set_rxfh	= netvsc_set_rxfh,
1253 	.get_link_ksettings = netvsc_get_link_ksettings,
1254 	.set_link_ksettings = netvsc_set_link_ksettings,
1255 };
1256 
1257 static const struct net_device_ops device_ops = {
1258 	.ndo_open =			netvsc_open,
1259 	.ndo_stop =			netvsc_close,
1260 	.ndo_start_xmit =		netvsc_start_xmit,
1261 	.ndo_set_rx_mode =		netvsc_set_multicast_list,
1262 	.ndo_change_mtu =		netvsc_change_mtu,
1263 	.ndo_validate_addr =		eth_validate_addr,
1264 	.ndo_set_mac_address =		netvsc_set_mac_addr,
1265 	.ndo_select_queue =		netvsc_select_queue,
1266 	.ndo_get_stats64 =		netvsc_get_stats64,
1267 #ifdef CONFIG_NET_POLL_CONTROLLER
1268 	.ndo_poll_controller =		netvsc_poll_controller,
1269 #endif
1270 };
1271 
1272 /*
1273  * Handle link status changes. For RNDIS_STATUS_NETWORK_CHANGE emulate link
1274  * down/up sequence. In case of RNDIS_STATUS_MEDIA_CONNECT when carrier is
1275  * present send GARP packet to network peers with netif_notify_peers().
1276  */
1277 static void netvsc_link_change(struct work_struct *w)
1278 {
1279 	struct net_device_context *ndev_ctx =
1280 		container_of(w, struct net_device_context, dwork.work);
1281 	struct hv_device *device_obj = ndev_ctx->device_ctx;
1282 	struct net_device *net = hv_get_drvdata(device_obj);
1283 	struct netvsc_device *net_device;
1284 	struct rndis_device *rdev;
1285 	struct netvsc_reconfig *event = NULL;
1286 	bool notify = false, reschedule = false;
1287 	unsigned long flags, next_reconfig, delay;
1288 
1289 	rtnl_lock();
1290 	net_device = rtnl_dereference(ndev_ctx->nvdev);
1291 	if (!net_device)
1292 		goto out_unlock;
1293 
1294 	rdev = net_device->extension;
1295 
1296 	next_reconfig = ndev_ctx->last_reconfig + LINKCHANGE_INT;
1297 	if (time_is_after_jiffies(next_reconfig)) {
1298 		/* link_watch only sends one notification with current state
1299 		 * per second, avoid doing reconfig more frequently. Handle
1300 		 * wrap around.
1301 		 */
1302 		delay = next_reconfig - jiffies;
1303 		delay = delay < LINKCHANGE_INT ? delay : LINKCHANGE_INT;
1304 		schedule_delayed_work(&ndev_ctx->dwork, delay);
1305 		goto out_unlock;
1306 	}
1307 	ndev_ctx->last_reconfig = jiffies;
1308 
1309 	spin_lock_irqsave(&ndev_ctx->lock, flags);
1310 	if (!list_empty(&ndev_ctx->reconfig_events)) {
1311 		event = list_first_entry(&ndev_ctx->reconfig_events,
1312 					 struct netvsc_reconfig, list);
1313 		list_del(&event->list);
1314 		reschedule = !list_empty(&ndev_ctx->reconfig_events);
1315 	}
1316 	spin_unlock_irqrestore(&ndev_ctx->lock, flags);
1317 
1318 	if (!event)
1319 		goto out_unlock;
1320 
1321 	switch (event->event) {
1322 		/* Only the following events are possible due to the check in
1323 		 * netvsc_linkstatus_callback()
1324 		 */
1325 	case RNDIS_STATUS_MEDIA_CONNECT:
1326 		if (rdev->link_state) {
1327 			rdev->link_state = false;
1328 			netif_carrier_on(net);
1329 			netif_tx_wake_all_queues(net);
1330 		} else {
1331 			notify = true;
1332 		}
1333 		kfree(event);
1334 		break;
1335 	case RNDIS_STATUS_MEDIA_DISCONNECT:
1336 		if (!rdev->link_state) {
1337 			rdev->link_state = true;
1338 			netif_carrier_off(net);
1339 			netif_tx_stop_all_queues(net);
1340 		}
1341 		kfree(event);
1342 		break;
1343 	case RNDIS_STATUS_NETWORK_CHANGE:
1344 		/* Only makes sense if carrier is present */
1345 		if (!rdev->link_state) {
1346 			rdev->link_state = true;
1347 			netif_carrier_off(net);
1348 			netif_tx_stop_all_queues(net);
1349 			event->event = RNDIS_STATUS_MEDIA_CONNECT;
1350 			spin_lock_irqsave(&ndev_ctx->lock, flags);
1351 			list_add(&event->list, &ndev_ctx->reconfig_events);
1352 			spin_unlock_irqrestore(&ndev_ctx->lock, flags);
1353 			reschedule = true;
1354 		}
1355 		break;
1356 	}
1357 
1358 	rtnl_unlock();
1359 
1360 	if (notify)
1361 		netdev_notify_peers(net);
1362 
1363 	/* link_watch only sends one notification with current state per
1364 	 * second, handle next reconfig event in 2 seconds.
1365 	 */
1366 	if (reschedule)
1367 		schedule_delayed_work(&ndev_ctx->dwork, LINKCHANGE_INT);
1368 
1369 	return;
1370 
1371 out_unlock:
1372 	rtnl_unlock();
1373 }
1374 
1375 static struct net_device *get_netvsc_bymac(const u8 *mac)
1376 {
1377 	struct net_device *dev;
1378 
1379 	ASSERT_RTNL();
1380 
1381 	for_each_netdev(&init_net, dev) {
1382 		if (dev->netdev_ops != &device_ops)
1383 			continue;	/* not a netvsc device */
1384 
1385 		if (ether_addr_equal(mac, dev->perm_addr))
1386 			return dev;
1387 	}
1388 
1389 	return NULL;
1390 }
1391 
1392 static struct net_device *get_netvsc_byref(struct net_device *vf_netdev)
1393 {
1394 	struct net_device *dev;
1395 
1396 	ASSERT_RTNL();
1397 
1398 	for_each_netdev(&init_net, dev) {
1399 		struct net_device_context *net_device_ctx;
1400 
1401 		if (dev->netdev_ops != &device_ops)
1402 			continue;	/* not a netvsc device */
1403 
1404 		net_device_ctx = netdev_priv(dev);
1405 		if (net_device_ctx->nvdev == NULL)
1406 			continue;	/* device is removed */
1407 
1408 		if (rtnl_dereference(net_device_ctx->vf_netdev) == vf_netdev)
1409 			return dev;	/* a match */
1410 	}
1411 
1412 	return NULL;
1413 }
1414 
1415 static int netvsc_register_vf(struct net_device *vf_netdev)
1416 {
1417 	struct net_device *ndev;
1418 	struct net_device_context *net_device_ctx;
1419 	struct netvsc_device *netvsc_dev;
1420 
1421 	if (vf_netdev->addr_len != ETH_ALEN)
1422 		return NOTIFY_DONE;
1423 
1424 	/*
1425 	 * We will use the MAC address to locate the synthetic interface to
1426 	 * associate with the VF interface. If we don't find a matching
1427 	 * synthetic interface, move on.
1428 	 */
1429 	ndev = get_netvsc_bymac(vf_netdev->perm_addr);
1430 	if (!ndev)
1431 		return NOTIFY_DONE;
1432 
1433 	net_device_ctx = netdev_priv(ndev);
1434 	netvsc_dev = rtnl_dereference(net_device_ctx->nvdev);
1435 	if (!netvsc_dev || rtnl_dereference(net_device_ctx->vf_netdev))
1436 		return NOTIFY_DONE;
1437 
1438 	netdev_info(ndev, "VF registering: %s\n", vf_netdev->name);
1439 	/*
1440 	 * Take a reference on the module.
1441 	 */
1442 	try_module_get(THIS_MODULE);
1443 
1444 	dev_hold(vf_netdev);
1445 	rcu_assign_pointer(net_device_ctx->vf_netdev, vf_netdev);
1446 	return NOTIFY_OK;
1447 }
1448 
1449 static int netvsc_vf_up(struct net_device *vf_netdev)
1450 {
1451 	struct net_device *ndev;
1452 	struct netvsc_device *netvsc_dev;
1453 	struct net_device_context *net_device_ctx;
1454 
1455 	ndev = get_netvsc_byref(vf_netdev);
1456 	if (!ndev)
1457 		return NOTIFY_DONE;
1458 
1459 	net_device_ctx = netdev_priv(ndev);
1460 	netvsc_dev = rtnl_dereference(net_device_ctx->nvdev);
1461 
1462 	netdev_info(ndev, "VF up: %s\n", vf_netdev->name);
1463 
1464 	/*
1465 	 * Open the device before switching data path.
1466 	 */
1467 	rndis_filter_open(netvsc_dev);
1468 
1469 	/*
1470 	 * notify the host to switch the data path.
1471 	 */
1472 	netvsc_switch_datapath(ndev, true);
1473 	netdev_info(ndev, "Data path switched to VF: %s\n", vf_netdev->name);
1474 
1475 	netif_carrier_off(ndev);
1476 
1477 	/* Now notify peers through VF device. */
1478 	call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, vf_netdev);
1479 
1480 	return NOTIFY_OK;
1481 }
1482 
1483 static int netvsc_vf_down(struct net_device *vf_netdev)
1484 {
1485 	struct net_device *ndev;
1486 	struct netvsc_device *netvsc_dev;
1487 	struct net_device_context *net_device_ctx;
1488 
1489 	ndev = get_netvsc_byref(vf_netdev);
1490 	if (!ndev)
1491 		return NOTIFY_DONE;
1492 
1493 	net_device_ctx = netdev_priv(ndev);
1494 	netvsc_dev = rtnl_dereference(net_device_ctx->nvdev);
1495 
1496 	netdev_info(ndev, "VF down: %s\n", vf_netdev->name);
1497 	netvsc_switch_datapath(ndev, false);
1498 	netdev_info(ndev, "Data path switched from VF: %s\n", vf_netdev->name);
1499 	rndis_filter_close(netvsc_dev);
1500 	netif_carrier_on(ndev);
1501 
1502 	/* Now notify peers through netvsc device. */
1503 	call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, ndev);
1504 
1505 	return NOTIFY_OK;
1506 }
1507 
1508 static int netvsc_unregister_vf(struct net_device *vf_netdev)
1509 {
1510 	struct net_device *ndev;
1511 	struct net_device_context *net_device_ctx;
1512 
1513 	ndev = get_netvsc_byref(vf_netdev);
1514 	if (!ndev)
1515 		return NOTIFY_DONE;
1516 
1517 	net_device_ctx = netdev_priv(ndev);
1518 
1519 	netdev_info(ndev, "VF unregistering: %s\n", vf_netdev->name);
1520 
1521 	RCU_INIT_POINTER(net_device_ctx->vf_netdev, NULL);
1522 	dev_put(vf_netdev);
1523 	module_put(THIS_MODULE);
1524 	return NOTIFY_OK;
1525 }
1526 
1527 static int netvsc_probe(struct hv_device *dev,
1528 			const struct hv_vmbus_device_id *dev_id)
1529 {
1530 	struct net_device *net = NULL;
1531 	struct net_device_context *net_device_ctx;
1532 	struct netvsc_device_info device_info;
1533 	struct netvsc_device *nvdev;
1534 	int ret;
1535 
1536 	net = alloc_etherdev_mq(sizeof(struct net_device_context),
1537 				VRSS_CHANNEL_MAX);
1538 	if (!net)
1539 		return -ENOMEM;
1540 
1541 	netif_carrier_off(net);
1542 
1543 	netvsc_init_settings(net);
1544 
1545 	net_device_ctx = netdev_priv(net);
1546 	net_device_ctx->device_ctx = dev;
1547 	net_device_ctx->msg_enable = netif_msg_init(debug, default_msg);
1548 	if (netif_msg_probe(net_device_ctx))
1549 		netdev_dbg(net, "netvsc msg_enable: %d\n",
1550 			   net_device_ctx->msg_enable);
1551 
1552 	hv_set_drvdata(dev, net);
1553 
1554 	INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_link_change);
1555 	INIT_WORK(&net_device_ctx->work, do_set_multicast);
1556 
1557 	spin_lock_init(&net_device_ctx->lock);
1558 	INIT_LIST_HEAD(&net_device_ctx->reconfig_events);
1559 
1560 	net->netdev_ops = &device_ops;
1561 	net->ethtool_ops = &ethtool_ops;
1562 	SET_NETDEV_DEV(net, &dev->device);
1563 
1564 	/* We always need headroom for rndis header */
1565 	net->needed_headroom = RNDIS_AND_PPI_SIZE;
1566 
1567 	/* Notify the netvsc driver of the new device */
1568 	memset(&device_info, 0, sizeof(device_info));
1569 	device_info.ring_size = ring_size;
1570 	device_info.num_chn = VRSS_CHANNEL_DEFAULT;
1571 	ret = rndis_filter_device_add(dev, &device_info);
1572 	if (ret != 0) {
1573 		netdev_err(net, "unable to add netvsc device (ret %d)\n", ret);
1574 		free_netdev(net);
1575 		hv_set_drvdata(dev, NULL);
1576 		return ret;
1577 	}
1578 	memcpy(net->dev_addr, device_info.mac_adr, ETH_ALEN);
1579 
1580 	/* hw_features computed in rndis_filter_device_add */
1581 	net->features = net->hw_features |
1582 		NETIF_F_HIGHDMA | NETIF_F_SG |
1583 		NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX;
1584 	net->vlan_features = net->features;
1585 
1586 	/* RCU not necessary here, device not registered */
1587 	nvdev = net_device_ctx->nvdev;
1588 	netif_set_real_num_tx_queues(net, nvdev->num_chn);
1589 	netif_set_real_num_rx_queues(net, nvdev->num_chn);
1590 
1591 	/* MTU range: 68 - 1500 or 65521 */
1592 	net->min_mtu = NETVSC_MTU_MIN;
1593 	if (nvdev->nvsp_version >= NVSP_PROTOCOL_VERSION_2)
1594 		net->max_mtu = NETVSC_MTU - ETH_HLEN;
1595 	else
1596 		net->max_mtu = ETH_DATA_LEN;
1597 
1598 	ret = register_netdev(net);
1599 	if (ret != 0) {
1600 		pr_err("Unable to register netdev.\n");
1601 		rndis_filter_device_remove(dev, nvdev);
1602 		free_netdev(net);
1603 	}
1604 
1605 	return ret;
1606 }
1607 
1608 static int netvsc_remove(struct hv_device *dev)
1609 {
1610 	struct net_device *net;
1611 	struct net_device_context *ndev_ctx;
1612 
1613 	net = hv_get_drvdata(dev);
1614 
1615 	if (net == NULL) {
1616 		dev_err(&dev->device, "No net device to remove\n");
1617 		return 0;
1618 	}
1619 
1620 	ndev_ctx = netdev_priv(net);
1621 
1622 	netif_device_detach(net);
1623 
1624 	cancel_delayed_work_sync(&ndev_ctx->dwork);
1625 	cancel_work_sync(&ndev_ctx->work);
1626 
1627 	/*
1628 	 * Call to the vsc driver to let it know that the device is being
1629 	 * removed. Also blocks mtu and channel changes.
1630 	 */
1631 	rtnl_lock();
1632 	rndis_filter_device_remove(dev, ndev_ctx->nvdev);
1633 	rtnl_unlock();
1634 
1635 	unregister_netdev(net);
1636 
1637 	hv_set_drvdata(dev, NULL);
1638 
1639 	free_netdev(net);
1640 	return 0;
1641 }
1642 
1643 static const struct hv_vmbus_device_id id_table[] = {
1644 	/* Network guid */
1645 	{ HV_NIC_GUID, },
1646 	{ },
1647 };
1648 
1649 MODULE_DEVICE_TABLE(vmbus, id_table);
1650 
1651 /* The one and only one */
1652 static struct  hv_driver netvsc_drv = {
1653 	.name = KBUILD_MODNAME,
1654 	.id_table = id_table,
1655 	.probe = netvsc_probe,
1656 	.remove = netvsc_remove,
1657 };
1658 
1659 /*
1660  * On Hyper-V, every VF interface is matched with a corresponding
1661  * synthetic interface. The synthetic interface is presented first
1662  * to the guest. When the corresponding VF instance is registered,
1663  * we will take care of switching the data path.
1664  */
1665 static int netvsc_netdev_event(struct notifier_block *this,
1666 			       unsigned long event, void *ptr)
1667 {
1668 	struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
1669 
1670 	/* Skip our own events */
1671 	if (event_dev->netdev_ops == &device_ops)
1672 		return NOTIFY_DONE;
1673 
1674 	/* Avoid non-Ethernet type devices */
1675 	if (event_dev->type != ARPHRD_ETHER)
1676 		return NOTIFY_DONE;
1677 
1678 	/* Avoid Vlan dev with same MAC registering as VF */
1679 	if (is_vlan_dev(event_dev))
1680 		return NOTIFY_DONE;
1681 
1682 	/* Avoid Bonding master dev with same MAC registering as VF */
1683 	if ((event_dev->priv_flags & IFF_BONDING) &&
1684 	    (event_dev->flags & IFF_MASTER))
1685 		return NOTIFY_DONE;
1686 
1687 	switch (event) {
1688 	case NETDEV_REGISTER:
1689 		return netvsc_register_vf(event_dev);
1690 	case NETDEV_UNREGISTER:
1691 		return netvsc_unregister_vf(event_dev);
1692 	case NETDEV_UP:
1693 		return netvsc_vf_up(event_dev);
1694 	case NETDEV_DOWN:
1695 		return netvsc_vf_down(event_dev);
1696 	default:
1697 		return NOTIFY_DONE;
1698 	}
1699 }
1700 
1701 static struct notifier_block netvsc_netdev_notifier = {
1702 	.notifier_call = netvsc_netdev_event,
1703 };
1704 
1705 static void __exit netvsc_drv_exit(void)
1706 {
1707 	unregister_netdevice_notifier(&netvsc_netdev_notifier);
1708 	vmbus_driver_unregister(&netvsc_drv);
1709 }
1710 
1711 static int __init netvsc_drv_init(void)
1712 {
1713 	int ret;
1714 
1715 	if (ring_size < RING_SIZE_MIN) {
1716 		ring_size = RING_SIZE_MIN;
1717 		pr_info("Increased ring_size to %d (min allowed)\n",
1718 			ring_size);
1719 	}
1720 	ret = vmbus_driver_register(&netvsc_drv);
1721 
1722 	if (ret)
1723 		return ret;
1724 
1725 	register_netdevice_notifier(&netvsc_netdev_notifier);
1726 	return 0;
1727 }
1728 
1729 MODULE_LICENSE("GPL");
1730 MODULE_DESCRIPTION("Microsoft Hyper-V network driver");
1731 
1732 module_init(netvsc_drv_init);
1733 module_exit(netvsc_drv_exit);
1734