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
44#define RING_SIZE_MIN 64
45static int ring_size = 128;
46module_param(ring_size, int, S_IRUGO);
47MODULE_PARM_DESC(ring_size, "Ring buffer size (# of pages)");
48
49static const u32 default_msg = NETIF_MSG_DRV | NETIF_MSG_PROBE |
50				NETIF_MSG_LINK | NETIF_MSG_IFUP |
51				NETIF_MSG_IFDOWN | NETIF_MSG_RX_ERR |
52				NETIF_MSG_TX_ERR;
53
54static int debug = -1;
55module_param(debug, int, S_IRUGO);
56MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
57
58static void do_set_multicast(struct work_struct *w)
59{
60	struct net_device_context *ndevctx =
61		container_of(w, struct net_device_context, work);
62	struct netvsc_device *nvdev;
63	struct rndis_device *rdev;
64
65	nvdev = hv_get_drvdata(ndevctx->device_ctx);
66	if (nvdev == NULL || nvdev->ndev == NULL)
67		return;
68
69	rdev = nvdev->extension;
70	if (rdev == NULL)
71		return;
72
73	if (nvdev->ndev->flags & IFF_PROMISC)
74		rndis_filter_set_packet_filter(rdev,
75			NDIS_PACKET_TYPE_PROMISCUOUS);
76	else
77		rndis_filter_set_packet_filter(rdev,
78			NDIS_PACKET_TYPE_BROADCAST |
79			NDIS_PACKET_TYPE_ALL_MULTICAST |
80			NDIS_PACKET_TYPE_DIRECTED);
81}
82
83static void netvsc_set_multicast_list(struct net_device *net)
84{
85	struct net_device_context *net_device_ctx = netdev_priv(net);
86
87	schedule_work(&net_device_ctx->work);
88}
89
90static int netvsc_open(struct net_device *net)
91{
92	struct net_device_context *net_device_ctx = netdev_priv(net);
93	struct hv_device *device_obj = net_device_ctx->device_ctx;
94	struct netvsc_device *nvdev;
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(device_obj);
102	if (ret != 0) {
103		netdev_err(net, "unable to open device (ret %d).\n", ret);
104		return ret;
105	}
106
107	netif_tx_start_all_queues(net);
108
109	nvdev = hv_get_drvdata(device_obj);
110	rdev = nvdev->extension;
111	if (!rdev->link_state)
112		netif_carrier_on(net);
113
114	return ret;
115}
116
117static int netvsc_close(struct net_device *net)
118{
119	struct net_device_context *net_device_ctx = netdev_priv(net);
120	struct hv_device *device_obj = net_device_ctx->device_ctx;
121	int ret;
122
123	netif_tx_disable(net);
124
125	/* Make sure netvsc_set_multicast_list doesn't re-enable filter! */
126	cancel_work_sync(&net_device_ctx->work);
127	ret = rndis_filter_close(device_obj);
128	if (ret != 0)
129		netdev_err(net, "unable to close device (ret %d).\n", ret);
130
131	return ret;
132}
133
134static void *init_ppi_data(struct rndis_message *msg, u32 ppi_size,
135				int pkt_type)
136{
137	struct rndis_packet *rndis_pkt;
138	struct rndis_per_packet_info *ppi;
139
140	rndis_pkt = &msg->msg.pkt;
141	rndis_pkt->data_offset += ppi_size;
142
143	ppi = (struct rndis_per_packet_info *)((void *)rndis_pkt +
144		rndis_pkt->per_pkt_info_offset + rndis_pkt->per_pkt_info_len);
145
146	ppi->size = ppi_size;
147	ppi->type = pkt_type;
148	ppi->ppi_offset = sizeof(struct rndis_per_packet_info);
149
150	rndis_pkt->per_pkt_info_len += ppi_size;
151
152	return ppi;
153}
154
155union sub_key {
156	u64 k;
157	struct {
158		u8 pad[3];
159		u8 kb;
160		u32 ka;
161	};
162};
163
164/* Toeplitz hash function
165 * data: network byte order
166 * return: host byte order
167 */
168static u32 comp_hash(u8 *key, int klen, void *data, int dlen)
169{
170	union sub_key subk;
171	int k_next = 4;
172	u8 dt;
173	int i, j;
174	u32 ret = 0;
175
176	subk.k = 0;
177	subk.ka = ntohl(*(u32 *)key);
178
179	for (i = 0; i < dlen; i++) {
180		subk.kb = key[k_next];
181		k_next = (k_next + 1) % klen;
182		dt = ((u8 *)data)[i];
183		for (j = 0; j < 8; j++) {
184			if (dt & 0x80)
185				ret ^= subk.ka;
186			dt <<= 1;
187			subk.k <<= 1;
188		}
189	}
190
191	return ret;
192}
193
194static bool netvsc_set_hash(u32 *hash, struct sk_buff *skb)
195{
196	struct flow_keys flow;
197	int data_len;
198
199	if (!skb_flow_dissect(skb, &flow) ||
200	    !(flow.n_proto == htons(ETH_P_IP) ||
201	      flow.n_proto == htons(ETH_P_IPV6)))
202		return false;
203
204	if (flow.ip_proto == IPPROTO_TCP)
205		data_len = 12;
206	else
207		data_len = 8;
208
209	*hash = comp_hash(netvsc_hash_key, HASH_KEYLEN, &flow, data_len);
210
211	return true;
212}
213
214static u16 netvsc_select_queue(struct net_device *ndev, struct sk_buff *skb,
215			void *accel_priv, select_queue_fallback_t fallback)
216{
217	struct net_device_context *net_device_ctx = netdev_priv(ndev);
218	struct hv_device *hdev =  net_device_ctx->device_ctx;
219	struct netvsc_device *nvsc_dev = hv_get_drvdata(hdev);
220	u32 hash;
221	u16 q_idx = 0;
222
223	if (nvsc_dev == NULL || ndev->real_num_tx_queues <= 1)
224		return 0;
225
226	if (netvsc_set_hash(&hash, skb)) {
227		q_idx = nvsc_dev->send_table[hash % VRSS_SEND_TAB_SIZE] %
228			ndev->real_num_tx_queues;
229		skb_set_hash(skb, hash, PKT_HASH_TYPE_L3);
230	}
231
232	return q_idx;
233}
234
235void netvsc_xmit_completion(void *context)
236{
237	struct hv_netvsc_packet *packet = (struct hv_netvsc_packet *)context;
238	struct sk_buff *skb = (struct sk_buff *)
239		(unsigned long)packet->send_completion_tid;
240
241	if (skb)
242		dev_kfree_skb_any(skb);
243}
244
245static u32 fill_pg_buf(struct page *page, u32 offset, u32 len,
246			struct hv_page_buffer *pb)
247{
248	int j = 0;
249
250	/* Deal with compund pages by ignoring unused part
251	 * of the page.
252	 */
253	page += (offset >> PAGE_SHIFT);
254	offset &= ~PAGE_MASK;
255
256	while (len > 0) {
257		unsigned long bytes;
258
259		bytes = PAGE_SIZE - offset;
260		if (bytes > len)
261			bytes = len;
262		pb[j].pfn = page_to_pfn(page);
263		pb[j].offset = offset;
264		pb[j].len = bytes;
265
266		offset += bytes;
267		len -= bytes;
268
269		if (offset == PAGE_SIZE && len) {
270			page++;
271			offset = 0;
272			j++;
273		}
274	}
275
276	return j + 1;
277}
278
279static u32 init_page_array(void *hdr, u32 len, struct sk_buff *skb,
280			   struct hv_netvsc_packet *packet)
281{
282	struct hv_page_buffer *pb = packet->page_buf;
283	u32 slots_used = 0;
284	char *data = skb->data;
285	int frags = skb_shinfo(skb)->nr_frags;
286	int i;
287
288	/* The packet is laid out thus:
289	 * 1. hdr: RNDIS header and PPI
290	 * 2. skb linear data
291	 * 3. skb fragment data
292	 */
293	if (hdr != NULL)
294		slots_used += fill_pg_buf(virt_to_page(hdr),
295					offset_in_page(hdr),
296					len, &pb[slots_used]);
297
298	packet->rmsg_size = len;
299	packet->rmsg_pgcnt = slots_used;
300
301	slots_used += fill_pg_buf(virt_to_page(data),
302				offset_in_page(data),
303				skb_headlen(skb), &pb[slots_used]);
304
305	for (i = 0; i < frags; i++) {
306		skb_frag_t *frag = skb_shinfo(skb)->frags + i;
307
308		slots_used += fill_pg_buf(skb_frag_page(frag),
309					frag->page_offset,
310					skb_frag_size(frag), &pb[slots_used]);
311	}
312	return slots_used;
313}
314
315static int count_skb_frag_slots(struct sk_buff *skb)
316{
317	int i, frags = skb_shinfo(skb)->nr_frags;
318	int pages = 0;
319
320	for (i = 0; i < frags; i++) {
321		skb_frag_t *frag = skb_shinfo(skb)->frags + i;
322		unsigned long size = skb_frag_size(frag);
323		unsigned long offset = frag->page_offset;
324
325		/* Skip unused frames from start of page */
326		offset &= ~PAGE_MASK;
327		pages += PFN_UP(offset + size);
328	}
329	return pages;
330}
331
332static int netvsc_get_slots(struct sk_buff *skb)
333{
334	char *data = skb->data;
335	unsigned int offset = offset_in_page(data);
336	unsigned int len = skb_headlen(skb);
337	int slots;
338	int frag_slots;
339
340	slots = DIV_ROUND_UP(offset + len, PAGE_SIZE);
341	frag_slots = count_skb_frag_slots(skb);
342	return slots + frag_slots;
343}
344
345static u32 get_net_transport_info(struct sk_buff *skb, u32 *trans_off)
346{
347	u32 ret_val = TRANSPORT_INFO_NOT_IP;
348
349	if ((eth_hdr(skb)->h_proto != htons(ETH_P_IP)) &&
350		(eth_hdr(skb)->h_proto != htons(ETH_P_IPV6))) {
351		goto not_ip;
352	}
353
354	*trans_off = skb_transport_offset(skb);
355
356	if ((eth_hdr(skb)->h_proto == htons(ETH_P_IP))) {
357		struct iphdr *iphdr = ip_hdr(skb);
358
359		if (iphdr->protocol == IPPROTO_TCP)
360			ret_val = TRANSPORT_INFO_IPV4_TCP;
361		else if (iphdr->protocol == IPPROTO_UDP)
362			ret_val = TRANSPORT_INFO_IPV4_UDP;
363	} else {
364		if (ipv6_hdr(skb)->nexthdr == IPPROTO_TCP)
365			ret_val = TRANSPORT_INFO_IPV6_TCP;
366		else if (ipv6_hdr(skb)->nexthdr == IPPROTO_UDP)
367			ret_val = TRANSPORT_INFO_IPV6_UDP;
368	}
369
370not_ip:
371	return ret_val;
372}
373
374static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
375{
376	struct net_device_context *net_device_ctx = netdev_priv(net);
377	struct hv_netvsc_packet *packet = NULL;
378	int ret;
379	unsigned int num_data_pgs;
380	struct rndis_message *rndis_msg;
381	struct rndis_packet *rndis_pkt;
382	u32 rndis_msg_size;
383	bool isvlan;
384	bool linear = false;
385	struct rndis_per_packet_info *ppi;
386	struct ndis_tcp_ip_checksum_info *csum_info;
387	struct ndis_tcp_lso_info *lso_info;
388	int  hdr_offset;
389	u32 net_trans_info;
390	u32 hash;
391	u32 skb_length;
392	u32 pkt_sz;
393	struct hv_page_buffer page_buf[MAX_PAGE_BUFFER_COUNT];
394
395
396	/* We will atmost need two pages to describe the rndis
397	 * header. We can only transmit MAX_PAGE_BUFFER_COUNT number
398	 * of pages in a single packet. If skb is scattered around
399	 * more pages we try linearizing it.
400	 */
401
402check_size:
403	skb_length = skb->len;
404	num_data_pgs = netvsc_get_slots(skb) + 2;
405	if (num_data_pgs > MAX_PAGE_BUFFER_COUNT && linear) {
406		net_alert_ratelimited("packet too big: %u pages (%u bytes)\n",
407				      num_data_pgs, skb->len);
408		ret = -EFAULT;
409		goto drop;
410	} else if (num_data_pgs > MAX_PAGE_BUFFER_COUNT) {
411		if (skb_linearize(skb)) {
412			net_alert_ratelimited("failed to linearize skb\n");
413			ret = -ENOMEM;
414			goto drop;
415		}
416		linear = true;
417		goto check_size;
418	}
419
420	pkt_sz = sizeof(struct hv_netvsc_packet) + RNDIS_AND_PPI_SIZE;
421
422	ret = skb_cow_head(skb, pkt_sz);
423	if (ret) {
424		netdev_err(net, "unable to alloc hv_netvsc_packet\n");
425		ret = -ENOMEM;
426		goto drop;
427	}
428	/* Use the headroom for building up the packet */
429	packet = (struct hv_netvsc_packet *)skb->head;
430
431	packet->status = 0;
432	packet->xmit_more = skb->xmit_more;
433
434	packet->vlan_tci = skb->vlan_tci;
435	packet->page_buf = page_buf;
436
437	packet->q_idx = skb_get_queue_mapping(skb);
438
439	packet->is_data_pkt = true;
440	packet->total_data_buflen = skb->len;
441
442	packet->rndis_msg = (struct rndis_message *)((unsigned long)packet +
443				sizeof(struct hv_netvsc_packet));
444
445	memset(packet->rndis_msg, 0, RNDIS_AND_PPI_SIZE);
446
447	/* Set the completion routine */
448	packet->send_completion = netvsc_xmit_completion;
449	packet->send_completion_ctx = packet;
450	packet->send_completion_tid = (unsigned long)skb;
451
452	isvlan = packet->vlan_tci & VLAN_TAG_PRESENT;
453
454	/* Add the rndis header */
455	rndis_msg = packet->rndis_msg;
456	rndis_msg->ndis_msg_type = RNDIS_MSG_PACKET;
457	rndis_msg->msg_len = packet->total_data_buflen;
458	rndis_pkt = &rndis_msg->msg.pkt;
459	rndis_pkt->data_offset = sizeof(struct rndis_packet);
460	rndis_pkt->data_len = packet->total_data_buflen;
461	rndis_pkt->per_pkt_info_offset = sizeof(struct rndis_packet);
462
463	rndis_msg_size = RNDIS_MESSAGE_SIZE(struct rndis_packet);
464
465	hash = skb_get_hash_raw(skb);
466	if (hash != 0 && net->real_num_tx_queues > 1) {
467		rndis_msg_size += NDIS_HASH_PPI_SIZE;
468		ppi = init_ppi_data(rndis_msg, NDIS_HASH_PPI_SIZE,
469				    NBL_HASH_VALUE);
470		*(u32 *)((void *)ppi + ppi->ppi_offset) = hash;
471	}
472
473	if (isvlan) {
474		struct ndis_pkt_8021q_info *vlan;
475
476		rndis_msg_size += NDIS_VLAN_PPI_SIZE;
477		ppi = init_ppi_data(rndis_msg, NDIS_VLAN_PPI_SIZE,
478					IEEE_8021Q_INFO);
479		vlan = (struct ndis_pkt_8021q_info *)((void *)ppi +
480						ppi->ppi_offset);
481		vlan->vlanid = packet->vlan_tci & VLAN_VID_MASK;
482		vlan->pri = (packet->vlan_tci & VLAN_PRIO_MASK) >>
483				VLAN_PRIO_SHIFT;
484	}
485
486	net_trans_info = get_net_transport_info(skb, &hdr_offset);
487	if (net_trans_info == TRANSPORT_INFO_NOT_IP)
488		goto do_send;
489
490	/*
491	 * Setup the sendside checksum offload only if this is not a
492	 * GSO packet.
493	 */
494	if (skb_is_gso(skb))
495		goto do_lso;
496
497	if ((skb->ip_summed == CHECKSUM_NONE) ||
498	    (skb->ip_summed == CHECKSUM_UNNECESSARY))
499		goto do_send;
500
501	rndis_msg_size += NDIS_CSUM_PPI_SIZE;
502	ppi = init_ppi_data(rndis_msg, NDIS_CSUM_PPI_SIZE,
503			    TCPIP_CHKSUM_PKTINFO);
504
505	csum_info = (struct ndis_tcp_ip_checksum_info *)((void *)ppi +
506			ppi->ppi_offset);
507
508	if (net_trans_info & (INFO_IPV4 << 16))
509		csum_info->transmit.is_ipv4 = 1;
510	else
511		csum_info->transmit.is_ipv6 = 1;
512
513	if (net_trans_info & INFO_TCP) {
514		csum_info->transmit.tcp_checksum = 1;
515		csum_info->transmit.tcp_header_offset = hdr_offset;
516	} else if (net_trans_info & INFO_UDP) {
517		/* UDP checksum offload is not supported on ws2008r2.
518		 * Furthermore, on ws2012 and ws2012r2, there are some
519		 * issues with udp checksum offload from Linux guests.
520		 * (these are host issues).
521		 * For now compute the checksum here.
522		 */
523		struct udphdr *uh;
524		u16 udp_len;
525
526		ret = skb_cow_head(skb, 0);
527		if (ret)
528			goto drop;
529
530		uh = udp_hdr(skb);
531		udp_len = ntohs(uh->len);
532		uh->check = 0;
533		uh->check = csum_tcpudp_magic(ip_hdr(skb)->saddr,
534					      ip_hdr(skb)->daddr,
535					      udp_len, IPPROTO_UDP,
536					      csum_partial(uh, udp_len, 0));
537		if (uh->check == 0)
538			uh->check = CSUM_MANGLED_0;
539
540		csum_info->transmit.udp_checksum = 0;
541	}
542	goto do_send;
543
544do_lso:
545	rndis_msg_size += NDIS_LSO_PPI_SIZE;
546	ppi = init_ppi_data(rndis_msg, NDIS_LSO_PPI_SIZE,
547			    TCP_LARGESEND_PKTINFO);
548
549	lso_info = (struct ndis_tcp_lso_info *)((void *)ppi +
550			ppi->ppi_offset);
551
552	lso_info->lso_v2_transmit.type = NDIS_TCP_LARGE_SEND_OFFLOAD_V2_TYPE;
553	if (net_trans_info & (INFO_IPV4 << 16)) {
554		lso_info->lso_v2_transmit.ip_version =
555			NDIS_TCP_LARGE_SEND_OFFLOAD_IPV4;
556		ip_hdr(skb)->tot_len = 0;
557		ip_hdr(skb)->check = 0;
558		tcp_hdr(skb)->check =
559		~csum_tcpudp_magic(ip_hdr(skb)->saddr,
560				   ip_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
561	} else {
562		lso_info->lso_v2_transmit.ip_version =
563			NDIS_TCP_LARGE_SEND_OFFLOAD_IPV6;
564		ipv6_hdr(skb)->payload_len = 0;
565		tcp_hdr(skb)->check =
566		~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
567				&ipv6_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
568	}
569	lso_info->lso_v2_transmit.tcp_header_offset = hdr_offset;
570	lso_info->lso_v2_transmit.mss = skb_shinfo(skb)->gso_size;
571
572do_send:
573	/* Start filling in the page buffers with the rndis hdr */
574	rndis_msg->msg_len += rndis_msg_size;
575	packet->total_data_buflen = rndis_msg->msg_len;
576	packet->page_buf_cnt = init_page_array(rndis_msg, rndis_msg_size,
577					       skb, packet);
578
579	ret = netvsc_send(net_device_ctx->device_ctx, packet);
580
581drop:
582	if (ret == 0) {
583		net->stats.tx_bytes += skb_length;
584		net->stats.tx_packets++;
585	} else {
586		if (ret != -EAGAIN) {
587			dev_kfree_skb_any(skb);
588			net->stats.tx_dropped++;
589		}
590	}
591
592	return (ret == -EAGAIN) ? NETDEV_TX_BUSY : NETDEV_TX_OK;
593}
594
595/*
596 * netvsc_linkstatus_callback - Link up/down notification
597 */
598void netvsc_linkstatus_callback(struct hv_device *device_obj,
599				struct rndis_message *resp)
600{
601	struct rndis_indicate_status *indicate = &resp->msg.indicate_status;
602	struct net_device *net;
603	struct net_device_context *ndev_ctx;
604	struct netvsc_device *net_device;
605	struct rndis_device *rdev;
606
607	net_device = hv_get_drvdata(device_obj);
608	rdev = net_device->extension;
609
610	switch (indicate->status) {
611	case RNDIS_STATUS_MEDIA_CONNECT:
612		rdev->link_state = false;
613		break;
614	case RNDIS_STATUS_MEDIA_DISCONNECT:
615		rdev->link_state = true;
616		break;
617	case RNDIS_STATUS_NETWORK_CHANGE:
618		rdev->link_change = true;
619		break;
620	default:
621		return;
622	}
623
624	net = net_device->ndev;
625
626	if (!net || net->reg_state != NETREG_REGISTERED)
627		return;
628
629	ndev_ctx = netdev_priv(net);
630	if (!rdev->link_state) {
631		schedule_delayed_work(&ndev_ctx->dwork, 0);
632		schedule_delayed_work(&ndev_ctx->dwork, msecs_to_jiffies(20));
633	} else {
634		schedule_delayed_work(&ndev_ctx->dwork, 0);
635	}
636}
637
638/*
639 * netvsc_recv_callback -  Callback when we receive a packet from the
640 * "wire" on the specified device.
641 */
642int netvsc_recv_callback(struct hv_device *device_obj,
643				struct hv_netvsc_packet *packet,
644				struct ndis_tcp_ip_checksum_info *csum_info)
645{
646	struct net_device *net;
647	struct sk_buff *skb;
648
649	net = ((struct netvsc_device *)hv_get_drvdata(device_obj))->ndev;
650	if (!net || net->reg_state != NETREG_REGISTERED) {
651		packet->status = NVSP_STAT_FAIL;
652		return 0;
653	}
654
655	/* Allocate a skb - TODO direct I/O to pages? */
656	skb = netdev_alloc_skb_ip_align(net, packet->total_data_buflen);
657	if (unlikely(!skb)) {
658		++net->stats.rx_dropped;
659		packet->status = NVSP_STAT_FAIL;
660		return 0;
661	}
662
663	/*
664	 * Copy to skb. This copy is needed here since the memory pointed by
665	 * hv_netvsc_packet cannot be deallocated
666	 */
667	memcpy(skb_put(skb, packet->total_data_buflen), packet->data,
668		packet->total_data_buflen);
669
670	skb->protocol = eth_type_trans(skb, net);
671	if (csum_info) {
672		/* We only look at the IP checksum here.
673		 * Should we be dropping the packet if checksum
674		 * failed? How do we deal with other checksums - TCP/UDP?
675		 */
676		if (csum_info->receive.ip_checksum_succeeded)
677			skb->ip_summed = CHECKSUM_UNNECESSARY;
678		else
679			skb->ip_summed = CHECKSUM_NONE;
680	}
681
682	if (packet->vlan_tci & VLAN_TAG_PRESENT)
683		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
684				       packet->vlan_tci);
685
686	skb_record_rx_queue(skb, packet->channel->
687			    offermsg.offer.sub_channel_index);
688
689	net->stats.rx_packets++;
690	net->stats.rx_bytes += packet->total_data_buflen;
691
692	/*
693	 * Pass the skb back up. Network stack will deallocate the skb when it
694	 * is done.
695	 * TODO - use NAPI?
696	 */
697	netif_rx(skb);
698
699	return 0;
700}
701
702static void netvsc_get_drvinfo(struct net_device *net,
703			       struct ethtool_drvinfo *info)
704{
705	strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
706	strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
707}
708
709static void netvsc_get_channels(struct net_device *net,
710				struct ethtool_channels *channel)
711{
712	struct net_device_context *net_device_ctx = netdev_priv(net);
713	struct hv_device *dev = net_device_ctx->device_ctx;
714	struct netvsc_device *nvdev = hv_get_drvdata(dev);
715
716	if (nvdev) {
717		channel->max_combined	= nvdev->max_chn;
718		channel->combined_count = nvdev->num_chn;
719	}
720}
721
722static int netvsc_change_mtu(struct net_device *ndev, int mtu)
723{
724	struct net_device_context *ndevctx = netdev_priv(ndev);
725	struct hv_device *hdev =  ndevctx->device_ctx;
726	struct netvsc_device *nvdev = hv_get_drvdata(hdev);
727	struct netvsc_device_info device_info;
728	int limit = ETH_DATA_LEN;
729
730	if (nvdev == NULL || nvdev->destroy)
731		return -ENODEV;
732
733	if (nvdev->nvsp_version >= NVSP_PROTOCOL_VERSION_2)
734		limit = NETVSC_MTU - ETH_HLEN;
735
736	/* Hyper-V hosts don't support MTU < ETH_DATA_LEN (1500) */
737	if (mtu < ETH_DATA_LEN || mtu > limit)
738		return -EINVAL;
739
740	nvdev->start_remove = true;
741	cancel_work_sync(&ndevctx->work);
742	netif_tx_disable(ndev);
743	rndis_filter_device_remove(hdev);
744
745	ndev->mtu = mtu;
746
747	ndevctx->device_ctx = hdev;
748	hv_set_drvdata(hdev, ndev);
749	device_info.ring_size = ring_size;
750	rndis_filter_device_add(hdev, &device_info);
751	netif_tx_wake_all_queues(ndev);
752
753	return 0;
754}
755
756
757static int netvsc_set_mac_addr(struct net_device *ndev, void *p)
758{
759	struct net_device_context *ndevctx = netdev_priv(ndev);
760	struct hv_device *hdev =  ndevctx->device_ctx;
761	struct sockaddr *addr = p;
762	char save_adr[ETH_ALEN];
763	unsigned char save_aatype;
764	int err;
765
766	memcpy(save_adr, ndev->dev_addr, ETH_ALEN);
767	save_aatype = ndev->addr_assign_type;
768
769	err = eth_mac_addr(ndev, p);
770	if (err != 0)
771		return err;
772
773	err = rndis_filter_set_device_mac(hdev, addr->sa_data);
774	if (err != 0) {
775		/* roll back to saved MAC */
776		memcpy(ndev->dev_addr, save_adr, ETH_ALEN);
777		ndev->addr_assign_type = save_aatype;
778	}
779
780	return err;
781}
782
783#ifdef CONFIG_NET_POLL_CONTROLLER
784static void netvsc_poll_controller(struct net_device *net)
785{
786	/* As netvsc_start_xmit() works synchronous we don't have to
787	 * trigger anything here.
788	 */
789}
790#endif
791
792static const struct ethtool_ops ethtool_ops = {
793	.get_drvinfo	= netvsc_get_drvinfo,
794	.get_link	= ethtool_op_get_link,
795	.get_channels   = netvsc_get_channels,
796};
797
798static const struct net_device_ops device_ops = {
799	.ndo_open =			netvsc_open,
800	.ndo_stop =			netvsc_close,
801	.ndo_start_xmit =		netvsc_start_xmit,
802	.ndo_set_rx_mode =		netvsc_set_multicast_list,
803	.ndo_change_mtu =		netvsc_change_mtu,
804	.ndo_validate_addr =		eth_validate_addr,
805	.ndo_set_mac_address =		netvsc_set_mac_addr,
806	.ndo_select_queue =		netvsc_select_queue,
807#ifdef CONFIG_NET_POLL_CONTROLLER
808	.ndo_poll_controller =		netvsc_poll_controller,
809#endif
810};
811
812/*
813 * Send GARP packet to network peers after migrations.
814 * After Quick Migration, the network is not immediately operational in the
815 * current context when receiving RNDIS_STATUS_MEDIA_CONNECT event. So, add
816 * another netif_notify_peers() into a delayed work, otherwise GARP packet
817 * will not be sent after quick migration, and cause network disconnection.
818 * Also, we update the carrier status here.
819 */
820static void netvsc_link_change(struct work_struct *w)
821{
822	struct net_device_context *ndev_ctx;
823	struct net_device *net;
824	struct netvsc_device *net_device;
825	struct rndis_device *rdev;
826	bool notify, refresh = false;
827	char *argv[] = { "/etc/init.d/network", "restart", NULL };
828	char *envp[] = { "HOME=/", "PATH=/sbin:/usr/sbin:/bin:/usr/bin", NULL };
829
830	rtnl_lock();
831
832	ndev_ctx = container_of(w, struct net_device_context, dwork.work);
833	net_device = hv_get_drvdata(ndev_ctx->device_ctx);
834	rdev = net_device->extension;
835	net = net_device->ndev;
836
837	if (rdev->link_state) {
838		netif_carrier_off(net);
839		notify = false;
840	} else {
841		netif_carrier_on(net);
842		notify = true;
843		if (rdev->link_change) {
844			rdev->link_change = false;
845			refresh = true;
846		}
847	}
848
849	rtnl_unlock();
850
851	if (refresh)
852		call_usermodehelper(argv[0], argv, envp, UMH_WAIT_EXEC);
853
854	if (notify)
855		netdev_notify_peers(net);
856}
857
858
859static int netvsc_probe(struct hv_device *dev,
860			const struct hv_vmbus_device_id *dev_id)
861{
862	struct net_device *net = NULL;
863	struct net_device_context *net_device_ctx;
864	struct netvsc_device_info device_info;
865	struct netvsc_device *nvdev;
866	int ret;
867	u32 max_needed_headroom;
868
869	net = alloc_etherdev_mq(sizeof(struct net_device_context),
870				num_online_cpus());
871	if (!net)
872		return -ENOMEM;
873
874	max_needed_headroom = sizeof(struct hv_netvsc_packet) +
875			      RNDIS_AND_PPI_SIZE;
876
877	netif_carrier_off(net);
878
879	net_device_ctx = netdev_priv(net);
880	net_device_ctx->device_ctx = dev;
881	net_device_ctx->msg_enable = netif_msg_init(debug, default_msg);
882	if (netif_msg_probe(net_device_ctx))
883		netdev_dbg(net, "netvsc msg_enable: %d\n",
884			   net_device_ctx->msg_enable);
885
886	hv_set_drvdata(dev, net);
887	INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_link_change);
888	INIT_WORK(&net_device_ctx->work, do_set_multicast);
889
890	net->netdev_ops = &device_ops;
891
892	net->hw_features = NETIF_F_RXCSUM | NETIF_F_SG | NETIF_F_IP_CSUM |
893				NETIF_F_TSO;
894	net->features = NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_SG | NETIF_F_RXCSUM |
895			NETIF_F_IP_CSUM | NETIF_F_TSO;
896
897	net->ethtool_ops = &ethtool_ops;
898	SET_NETDEV_DEV(net, &dev->device);
899
900	/*
901	 * Request additional head room in the skb.
902	 * We will use this space to build the rndis
903	 * heaser and other state we need to maintain.
904	 */
905	net->needed_headroom = max_needed_headroom;
906
907	/* Notify the netvsc driver of the new device */
908	device_info.ring_size = ring_size;
909	ret = rndis_filter_device_add(dev, &device_info);
910	if (ret != 0) {
911		netdev_err(net, "unable to add netvsc device (ret %d)\n", ret);
912		free_netdev(net);
913		hv_set_drvdata(dev, NULL);
914		return ret;
915	}
916	memcpy(net->dev_addr, device_info.mac_adr, ETH_ALEN);
917
918	nvdev = hv_get_drvdata(dev);
919	netif_set_real_num_tx_queues(net, nvdev->num_chn);
920	netif_set_real_num_rx_queues(net, nvdev->num_chn);
921
922	ret = register_netdev(net);
923	if (ret != 0) {
924		pr_err("Unable to register netdev.\n");
925		rndis_filter_device_remove(dev);
926		free_netdev(net);
927	} else {
928		schedule_delayed_work(&net_device_ctx->dwork, 0);
929	}
930
931	return ret;
932}
933
934static int netvsc_remove(struct hv_device *dev)
935{
936	struct net_device *net;
937	struct net_device_context *ndev_ctx;
938	struct netvsc_device *net_device;
939
940	net_device = hv_get_drvdata(dev);
941	net = net_device->ndev;
942
943	if (net == NULL) {
944		dev_err(&dev->device, "No net device to remove\n");
945		return 0;
946	}
947
948	net_device->start_remove = true;
949
950	ndev_ctx = netdev_priv(net);
951	cancel_delayed_work_sync(&ndev_ctx->dwork);
952	cancel_work_sync(&ndev_ctx->work);
953
954	/* Stop outbound asap */
955	netif_tx_disable(net);
956
957	unregister_netdev(net);
958
959	/*
960	 * Call to the vsc driver to let it know that the device is being
961	 * removed
962	 */
963	rndis_filter_device_remove(dev);
964
965	free_netdev(net);
966	return 0;
967}
968
969static const struct hv_vmbus_device_id id_table[] = {
970	/* Network guid */
971	{ HV_NIC_GUID, },
972	{ },
973};
974
975MODULE_DEVICE_TABLE(vmbus, id_table);
976
977/* The one and only one */
978static struct  hv_driver netvsc_drv = {
979	.name = KBUILD_MODNAME,
980	.id_table = id_table,
981	.probe = netvsc_probe,
982	.remove = netvsc_remove,
983};
984
985static void __exit netvsc_drv_exit(void)
986{
987	vmbus_driver_unregister(&netvsc_drv);
988}
989
990static int __init netvsc_drv_init(void)
991{
992	if (ring_size < RING_SIZE_MIN) {
993		ring_size = RING_SIZE_MIN;
994		pr_info("Increased ring_size to %d (min allowed)\n",
995			ring_size);
996	}
997	return vmbus_driver_register(&netvsc_drv);
998}
999
1000MODULE_LICENSE("GPL");
1001MODULE_DESCRIPTION("Microsoft Hyper-V network driver");
1002
1003module_init(netvsc_drv_init);
1004module_exit(netvsc_drv_exit);
1005