[mirror_ubuntu-bionic-kernel.git] / drivers / staging / hv / netvsc_drv.c

/*
 * Copyright (c) 2009, Microsoft Corporation.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
 * Place - Suite 330, Boston, MA 02111-1307 USA.
 *
 * Authors:
 *   Haiyang Zhang <haiyangz@microsoft.com>
 *   Hank Janssen  <hjanssen@microsoft.com>
 */
#include <linux/init.h>
#include <linux/module.h>
#include <linux/highmem.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <linux/netdevice.h>
#include <linux/inetdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/in.h>
#include <linux/slab.h>
#include <net/arp.h>
#include <net/route.h>
#include <net/sock.h>
#include <net/pkt_sched.h>
#include "osd.h"
#include "logging.h"
#include "VersionInfo.h"
#include "vmbus.h"
#include "NetVscApi.h"

struct net_device_context {
	/* point back to our device context */
	struct vm_device *device_ctx;
	unsigned long avail;
};

struct netvsc_driver_context {
	/* !! These must be the first 2 fields !! */
	/* Which is a bug FIXME! */
	struct driver_context drv_ctx;
	struct netvsc_driver drv_obj;
};

#define PACKET_PAGES_LOWATER  8
/* Need this many pages to handle worst case fragmented packet */
#define PACKET_PAGES_HIWATER  (MAX_SKB_FRAGS + 2)

static int ring_size = roundup_pow_of_two(2*MAX_SKB_FRAGS+1);
module_param(ring_size, int, S_IRUGO);
MODULE_PARM_DESC(ring_size, "Ring buffer size (# of pages)");

/* The one and only one */
static struct netvsc_driver_context g_netvsc_drv;

static void netvsc_set_multicast_list(struct net_device *net)
{
}

static int netvsc_open(struct net_device *net)
{
	struct net_device_context *net_device_ctx = netdev_priv(net);
	struct hv_device *device_obj = &net_device_ctx->device_ctx->device_obj;
	int ret = 0;

	DPRINT_ENTER(NETVSC_DRV);

	if (netif_carrier_ok(net)) {
		/* Open up the device */
		ret = RndisFilterOnOpen(device_obj);
		if (ret != 0) {
			DPRINT_ERR(NETVSC_DRV,
				   "unable to open device (ret %d).", ret);
			return ret;
		}

		netif_start_queue(net);
	} else {
		DPRINT_ERR(NETVSC_DRV, "unable to open device...link is down.");
	}

	DPRINT_EXIT(NETVSC_DRV);
	return ret;
}

static int netvsc_close(struct net_device *net)
{
	struct net_device_context *net_device_ctx = netdev_priv(net);
	struct hv_device *device_obj = &net_device_ctx->device_ctx->device_obj;
	int ret;

	DPRINT_ENTER(NETVSC_DRV);

	netif_stop_queue(net);

	ret = RndisFilterOnClose(device_obj);
	if (ret != 0)
		DPRINT_ERR(NETVSC_DRV, "unable to close device (ret %d).", ret);

	DPRINT_EXIT(NETVSC_DRV);

	return ret;
}

static void netvsc_xmit_completion(void *context)
{
	struct hv_netvsc_packet *packet = (struct hv_netvsc_packet *)context;
	struct sk_buff *skb = (struct sk_buff *)
		(unsigned long)packet->Completion.Send.SendCompletionTid;

	DPRINT_ENTER(NETVSC_DRV);

	kfree(packet);

	if (skb) {
		struct net_device *net = skb->dev;
		struct net_device_context *net_device_ctx = netdev_priv(net);
		unsigned int num_pages = skb_shinfo(skb)->nr_frags + 2;

		dev_kfree_skb_any(skb);

		if ((net_device_ctx->avail += num_pages) >= PACKET_PAGES_HIWATER)
 			netif_wake_queue(net);
	}

	DPRINT_EXIT(NETVSC_DRV);
}

static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
{
	struct net_device_context *net_device_ctx = netdev_priv(net);
	struct driver_context *driver_ctx =
	    driver_to_driver_context(net_device_ctx->device_ctx->device.driver);
	struct netvsc_driver_context *net_drv_ctx =
		(struct netvsc_driver_context *)driver_ctx;
	struct netvsc_driver *net_drv_obj = &net_drv_ctx->drv_obj;
	struct hv_netvsc_packet *packet;
	int ret;
	unsigned int i, num_pages;

	DPRINT_ENTER(NETVSC_DRV);

	DPRINT_DBG(NETVSC_DRV, "xmit packet - len %d data_len %d",
		   skb->len, skb->data_len);

	/* Add 1 for skb->data and additional one for RNDIS */
	num_pages = skb_shinfo(skb)->nr_frags + 1 + 1;
	if (num_pages > net_device_ctx->avail)
		return NETDEV_TX_BUSY;

	/* Allocate a netvsc packet based on # of frags. */
	packet = kzalloc(sizeof(struct hv_netvsc_packet) +
			 (num_pages * sizeof(struct hv_page_buffer)) +
			 net_drv_obj->RequestExtSize, GFP_ATOMIC);
	if (!packet) {
		/* out of memory, silently drop packet */
		DPRINT_ERR(NETVSC_DRV, "unable to allocate hv_netvsc_packet");

		dev_kfree_skb(skb);
		net->stats.tx_dropped++;
		return NETDEV_TX_OK;
	}

	packet->Extension = (void *)(unsigned long)packet +
				sizeof(struct hv_netvsc_packet) +
				    (num_pages * sizeof(struct hv_page_buffer));

	/* Setup the rndis header */
	packet->PageBufferCount = num_pages;

	/* TODO: Flush all write buffers/ memory fence ??? */
	/* wmb(); */

	/* Initialize it from the skb */
	packet->TotalDataBufferLength	= skb->len;

	/* Start filling in the page buffers starting after RNDIS buffer. */
	packet->PageBuffers[1].Pfn = virt_to_phys(skb->data) >> PAGE_SHIFT;
	packet->PageBuffers[1].Offset
		= (unsigned long)skb->data & (PAGE_SIZE - 1);
	packet->PageBuffers[1].Length = skb_headlen(skb);

	/* Additional fragments are after SKB data */
	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
		skb_frag_t *f = &skb_shinfo(skb)->frags[i];

		packet->PageBuffers[i+2].Pfn = page_to_pfn(f->page);
		packet->PageBuffers[i+2].Offset = f->page_offset;
		packet->PageBuffers[i+2].Length = f->size;
	}

	/* Set the completion routine */
	packet->Completion.Send.OnSendCompletion = netvsc_xmit_completion;
	packet->Completion.Send.SendCompletionContext = packet;
	packet->Completion.Send.SendCompletionTid = (unsigned long)skb;

	ret = net_drv_obj->OnSend(&net_device_ctx->device_ctx->device_obj,
				  packet);
	if (ret == 0) {
		net->stats.tx_bytes += skb->len;
		net->stats.tx_packets++;

		DPRINT_DBG(NETVSC_DRV, "# of xmits %lu total size %lu",
			   net->stats.tx_packets,
			   net->stats.tx_bytes);

		if ((net_device_ctx->avail -= num_pages) < PACKET_PAGES_LOWATER)
			netif_stop_queue(net);
	} else {
		/* we are shutting down or bus overloaded, just drop packet */
		net->stats.tx_dropped++;
		netvsc_xmit_completion(packet);
	}

	DPRINT_EXIT(NETVSC_DRV);
	return NETDEV_TX_OK;
}

/*
 * netvsc_linkstatus_callback - Link up/down notification
 */
static void netvsc_linkstatus_callback(struct hv_device *device_obj,
				       unsigned int status)
{
	struct vm_device *device_ctx = to_vm_device(device_obj);
	struct net_device *net = dev_get_drvdata(&device_ctx->device);

	DPRINT_ENTER(NETVSC_DRV);

	if (!net) {
		DPRINT_ERR(NETVSC_DRV, "got link status but net device "
				"not initialized yet");
		return;
	}

	if (status == 1) {
		netif_carrier_on(net);
		netif_wake_queue(net);
	} else {
		netif_carrier_off(net);
		netif_stop_queue(net);
	}
	DPRINT_EXIT(NETVSC_DRV);
}

/*
 * netvsc_recv_callback -  Callback when we receive a packet from the
 * "wire" on the specified device.
 */
static int netvsc_recv_callback(struct hv_device *device_obj,
				struct hv_netvsc_packet *packet)
{
	struct vm_device *device_ctx = to_vm_device(device_obj);
	struct net_device *net = dev_get_drvdata(&device_ctx->device);
	struct sk_buff *skb;
	void *data;
	int i;
	unsigned long flags;

	DPRINT_ENTER(NETVSC_DRV);

	if (!net) {
		DPRINT_ERR(NETVSC_DRV, "got receive callback but net device "
				"not initialized yet");
		return 0;
	}

	/* Allocate a skb - TODO direct I/O to pages? */
	skb = netdev_alloc_skb_ip_align(net, packet->TotalDataBufferLength);
	if (unlikely(!skb)) {
		++net->stats.rx_dropped;
		return 0;
	}

	/* for kmap_atomic */
	local_irq_save(flags);

	/*
	 * Copy to skb. This copy is needed here since the memory pointed by
	 * hv_netvsc_packet cannot be deallocated
	 */
	for (i = 0; i < packet->PageBufferCount; i++) {
		data = kmap_atomic(pfn_to_page(packet->PageBuffers[i].Pfn),
					       KM_IRQ1);
		data = (void *)(unsigned long)data +
				packet->PageBuffers[i].Offset;

		memcpy(skb_put(skb, packet->PageBuffers[i].Length), data,
		       packet->PageBuffers[i].Length);

		kunmap_atomic((void *)((unsigned long)data -
				       packet->PageBuffers[i].Offset), KM_IRQ1);
	}

	local_irq_restore(flags);

	skb->protocol = eth_type_trans(skb, net);
	skb->ip_summed = CHECKSUM_NONE;

	net->stats.rx_packets++;
	net->stats.rx_bytes += skb->len;

	/*
	 * Pass the skb back up. Network stack will deallocate the skb when it
	 * is done.
	 * TODO - use NAPI?
	 */
	netif_rx(skb);

	DPRINT_DBG(NETVSC_DRV, "# of recvs %lu total size %lu",
		   net->stats.rx_packets, net->stats.rx_bytes);

	DPRINT_EXIT(NETVSC_DRV);

	return 0;
}

static const struct net_device_ops device_ops = {
	.ndo_open =			netvsc_open,
	.ndo_stop =			netvsc_close,
	.ndo_start_xmit =		netvsc_start_xmit,
	.ndo_set_multicast_list =	netvsc_set_multicast_list,
};

static int netvsc_probe(struct device *device)
{
	struct driver_context *driver_ctx =
		driver_to_driver_context(device->driver);
	struct netvsc_driver_context *net_drv_ctx =
		(struct netvsc_driver_context *)driver_ctx;
	struct netvsc_driver *net_drv_obj = &net_drv_ctx->drv_obj;
	struct vm_device *device_ctx = device_to_vm_device(device);
	struct hv_device *device_obj = &device_ctx->device_obj;
	struct net_device *net = NULL;
	struct net_device_context *net_device_ctx;
	struct netvsc_device_info device_info;
	int ret;

	DPRINT_ENTER(NETVSC_DRV);

	if (!net_drv_obj->Base.OnDeviceAdd)
		return -1;

	net = alloc_netdev(sizeof(struct net_device_context), "seth%d",
			   ether_setup);
	if (!net)
		return -1;

	/* Set initial state */
	netif_carrier_off(net);
	netif_stop_queue(net);

	net_device_ctx = netdev_priv(net);
	net_device_ctx->device_ctx = device_ctx;
	net_device_ctx->avail = ring_size;
	dev_set_drvdata(device, net);

	/* Notify the netvsc driver of the new device */
	ret = net_drv_obj->Base.OnDeviceAdd(device_obj, &device_info);
	if (ret != 0) {
		free_netdev(net);
		dev_set_drvdata(device, NULL);

		DPRINT_ERR(NETVSC_DRV, "unable to add netvsc device (ret %d)",
			   ret);
		return ret;
	}

	/*
	 * If carrier is still off ie we did not get a link status callback,
	 * update it if necessary
	 */
	/*
	 * FIXME: We should use a atomic or test/set instead to avoid getting
	 * out of sync with the device's link status
	 */
	if (!netif_carrier_ok(net))
		if (!device_info.LinkState)
			netif_carrier_on(net);

	memcpy(net->dev_addr, device_info.MacAddr, ETH_ALEN);

	net->netdev_ops = &device_ops;

	/* TODO: Add GSO and Checksum offload */
	net->features = NETIF_F_SG;

	SET_NETDEV_DEV(net, device);

	ret = register_netdev(net);
	if (ret != 0) {
		/* Remove the device and release the resource */
		net_drv_obj->Base.OnDeviceRemove(device_obj);
		free_netdev(net);
	}

	DPRINT_EXIT(NETVSC_DRV);
	return ret;
}

static int netvsc_remove(struct device *device)
{
	struct driver_context *driver_ctx =
		driver_to_driver_context(device->driver);
	struct netvsc_driver_context *net_drv_ctx =
		(struct netvsc_driver_context *)driver_ctx;
	struct netvsc_driver *net_drv_obj = &net_drv_ctx->drv_obj;
	struct vm_device *device_ctx = device_to_vm_device(device);
	struct net_device *net = dev_get_drvdata(&device_ctx->device);
	struct hv_device *device_obj = &device_ctx->device_obj;
	int ret;

	DPRINT_ENTER(NETVSC_DRV);

	if (net == NULL) {
		DPRINT_INFO(NETVSC, "no net device to remove");
		DPRINT_EXIT(NETVSC_DRV);
		return 0;
	}

	if (!net_drv_obj->Base.OnDeviceRemove) {
		DPRINT_EXIT(NETVSC_DRV);
		return -1;
	}

	/* Stop outbound asap */
	netif_stop_queue(net);
	/* netif_carrier_off(net); */

	unregister_netdev(net);

	/*
	 * Call to the vsc driver to let it know that the device is being
	 * removed
	 */
	ret = net_drv_obj->Base.OnDeviceRemove(device_obj);
	if (ret != 0) {
		/* TODO: */
		DPRINT_ERR(NETVSC, "unable to remove vsc device (ret %d)", ret);
	}

	free_netdev(net);
	DPRINT_EXIT(NETVSC_DRV);
	return ret;
}

static int netvsc_drv_exit_cb(struct device *dev, void *data)
{
	struct device **curr = (struct device **)data;

	*curr = dev;
	/* stop iterating */
	return 1;
}

static void netvsc_drv_exit(void)
{
	struct netvsc_driver *netvsc_drv_obj = &g_netvsc_drv.drv_obj;
	struct driver_context *drv_ctx = &g_netvsc_drv.drv_ctx;
	struct device *current_dev;
	int ret;

	DPRINT_ENTER(NETVSC_DRV);

	while (1) {
		current_dev = NULL;

		/* Get the device */
		ret = driver_for_each_device(&drv_ctx->driver, NULL,
					     &current_dev, netvsc_drv_exit_cb);
		if (ret)
			DPRINT_WARN(NETVSC_DRV,
				    "driver_for_each_device returned %d", ret);

		if (current_dev == NULL)
			break;

		/* Initiate removal from the top-down */
		DPRINT_INFO(NETVSC_DRV, "unregistering device (%p)...",
			    current_dev);

		device_unregister(current_dev);
	}

	if (netvsc_drv_obj->Base.OnCleanup)
		netvsc_drv_obj->Base.OnCleanup(&netvsc_drv_obj->Base);

	vmbus_child_driver_unregister(drv_ctx);

	DPRINT_EXIT(NETVSC_DRV);

	return;
}

static int netvsc_drv_init(int (*drv_init)(struct hv_driver *drv))
{
	struct netvsc_driver *net_drv_obj = &g_netvsc_drv.drv_obj;
	struct driver_context *drv_ctx = &g_netvsc_drv.drv_ctx;
	int ret;

	DPRINT_ENTER(NETVSC_DRV);

	vmbus_get_interface(&net_drv_obj->Base.VmbusChannelInterface);

	net_drv_obj->RingBufferSize = ring_size * PAGE_SIZE;
	net_drv_obj->OnReceiveCallback = netvsc_recv_callback;
	net_drv_obj->OnLinkStatusChanged = netvsc_linkstatus_callback;

	/* Callback to client driver to complete the initialization */
	drv_init(&net_drv_obj->Base);

	drv_ctx->driver.name = net_drv_obj->Base.name;
	memcpy(&drv_ctx->class_id, &net_drv_obj->Base.deviceType,
	       sizeof(struct hv_guid));

	drv_ctx->probe = netvsc_probe;
	drv_ctx->remove = netvsc_remove;

	/* The driver belongs to vmbus */
	ret = vmbus_child_driver_register(drv_ctx);

	DPRINT_EXIT(NETVSC_DRV);

	return ret;
}

static int __init netvsc_init(void)
{
	int ret;

	DPRINT_ENTER(NETVSC_DRV);
	DPRINT_INFO(NETVSC_DRV, "Netvsc initializing....");

	ret = netvsc_drv_init(NetVscInitialize);

	DPRINT_EXIT(NETVSC_DRV);

	return ret;
}

static void __exit netvsc_exit(void)
{
	DPRINT_ENTER(NETVSC_DRV);
	netvsc_drv_exit();
	DPRINT_EXIT(NETVSC_DRV);
}

MODULE_LICENSE("GPL");
MODULE_VERSION(HV_DRV_VERSION);
MODULE_DESCRIPTION("Microsoft Hyper-V network driver");

module_init(netvsc_init);
module_exit(netvsc_exit);
Commit	Line	Data
fceaf24a	1	/*
fceaf24a HJ	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, write to the Free Software Foundation, Inc., 59 Temple
	15	* Place - Suite 330, Boston, MA 02111-1307 USA.
	16	*
	17	* Authors:
d0e94d17	18	* Haiyang Zhang <haiyangz@microsoft.com>
fceaf24a	19	* Hank Janssen <hjanssen@microsoft.com>
fceaf24a	20	*/
fceaf24a HJ	21	#include <linux/init.h>
	22	#include <linux/module.h>
	23	#include <linux/highmem.h>
	24	#include <linux/device.h>
fceaf24a	25	#include <linux/io.h>
fceaf24a HJ	26	#include <linux/delay.h>
	27	#include <linux/netdevice.h>
	28	#include <linux/inetdevice.h>
	29	#include <linux/etherdevice.h>
	30	#include <linux/skbuff.h>
	31	#include <linux/in.h>
5a0e3ad6	32	#include <linux/slab.h>
fceaf24a HJ	33	#include <net/arp.h>
	34	#include <net/route.h>
	35	#include <net/sock.h>
	36	#include <net/pkt_sched.h>
4983b39a	37	#include "osd.h"
645954c5	38	#include "logging.h"
26c14cc1	39	#include "VersionInfo.h"
870cde80	40	#include "vmbus.h"
cc211812	41	#include "NetVscApi.h"
fceaf24a	42
fceaf24a	43	struct net_device_context {
02fafbc6	44	/* point back to our device context */
f916a34d	45	struct vm_device *device_ctx;
b220f5f9	46	unsigned long avail;
fceaf24a HJ	47	};
	48
	49	struct netvsc_driver_context {
454f18a9	50	/* !! These must be the first 2 fields !! */
7e23a6e9	51	/* Which is a bug FIXME! */
02fafbc6	52	struct driver_context drv_ctx;
7e23a6e9	53	struct netvsc_driver drv_obj;
fceaf24a HJ	54	};
fceaf24a HJ	55
b220f5f9 SH	56	#define PACKET_PAGES_LOWATER 8
	57	/* Need this many pages to handle worst case fragmented packet */
	58	#define PACKET_PAGES_HIWATER (MAX_SKB_FRAGS + 2)
	59
450d7a4b SH	60	static int ring_size = roundup_pow_of_two(2*MAX_SKB_FRAGS+1);
	61	module_param(ring_size, int, S_IRUGO);
	62	MODULE_PARM_DESC(ring_size, "Ring buffer size (# of pages)");
fceaf24a	63
454f18a9	64	/* The one and only one */
fceaf24a HJ	65	static struct netvsc_driver_context g_netvsc_drv;
fceaf24a HJ	66
4e9bfefa	67	static void netvsc_set_multicast_list(struct net_device *net)
fceaf24a HJ	68	{
	69	}
	70
fceaf24a HJ	71	static int netvsc_open(struct net_device *net)
fceaf24a HJ	72	{
fceaf24a	73	struct net_device_context *net_device_ctx = netdev_priv(net);
3d3b5518	74	struct hv_device *device_obj = &net_device_ctx->device_ctx->device_obj;
02fafbc6	75	int ret = 0;
fceaf24a HJ	76
	77	DPRINT_ENTER(NETVSC_DRV);
	78
02fafbc6	79	if (netif_carrier_ok(net)) {
454f18a9	80	/* Open up the device */
2d075346	81	ret = RndisFilterOnOpen(device_obj);
02fafbc6 GKH	82	if (ret != 0) {
	83	DPRINT_ERR(NETVSC_DRV,
	84	"unable to open device (ret %d).", ret);
fceaf24a HJ	85	return ret;
	86	}
	87
	88	netif_start_queue(net);
02fafbc6	89	} else {
fceaf24a HJ	90	DPRINT_ERR(NETVSC_DRV, "unable to open device...link is down.");
	91	}
	92
	93	DPRINT_EXIT(NETVSC_DRV);
	94	return ret;
	95	}
	96
fceaf24a HJ	97	static int netvsc_close(struct net_device *net)
fceaf24a HJ	98	{
fceaf24a	99	struct net_device_context *net_device_ctx = netdev_priv(net);
3d3b5518	100	struct hv_device *device_obj = &net_device_ctx->device_ctx->device_obj;
02fafbc6	101	int ret;
fceaf24a HJ	102
	103	DPRINT_ENTER(NETVSC_DRV);
	104
	105	netif_stop_queue(net);
	106
4f28900b	107	ret = RndisFilterOnClose(device_obj);
fceaf24a	108	if (ret != 0)
fceaf24a	109	DPRINT_ERR(NETVSC_DRV, "unable to close device (ret %d).", ret);
fceaf24a HJ	110
	111	DPRINT_EXIT(NETVSC_DRV);
	112
	113	return ret;
	114	}
	115
fceaf24a HJ	116	static void netvsc_xmit_completion(void *context)
fceaf24a HJ	117	{
4193d4f4	118	struct hv_netvsc_packet packet = (struct hv_netvsc_packet )context;
02fafbc6 GKH	119	struct sk_buff skb = (struct sk_buff )
02fafbc6 GKH	120	(unsigned long)packet->Completion.Send.SendCompletionTid;
fceaf24a HJ	121
	122	DPRINT_ENTER(NETVSC_DRV);
	123
	124	kfree(packet);
	125
02fafbc6	126	if (skb) {
7880fc54	127	struct net_device *net = skb->dev;
b220f5f9 SH	128	struct net_device_context *net_device_ctx = netdev_priv(net);
b220f5f9 SH	129	unsigned int num_pages = skb_shinfo(skb)->nr_frags + 2;
fceaf24a	130
b220f5f9	131	dev_kfree_skb_any(skb);
fceaf24a	132
b220f5f9 SH	133	if ((net_device_ctx->avail += num_pages) >= PACKET_PAGES_HIWATER)
b220f5f9 SH	134	netif_wake_queue(net);
fceaf24a HJ	135	}
	136
	137	DPRINT_EXIT(NETVSC_DRV);
	138	}
	139
02fafbc6	140	static int netvsc_start_xmit(struct sk_buff skb, struct net_device net)
fceaf24a	141	{
fceaf24a	142	struct net_device_context *net_device_ctx = netdev_priv(net);
02fafbc6 GKH	143	struct driver_context *driver_ctx =
	144	driver_to_driver_context(net_device_ctx->device_ctx->device.driver);
	145	struct netvsc_driver_context *net_drv_ctx =
	146	(struct netvsc_driver_context *)driver_ctx;
7e23a6e9	147	struct netvsc_driver *net_drv_obj = &net_drv_ctx->drv_obj;
4193d4f4	148	struct hv_netvsc_packet *packet;
02fafbc6	149	int ret;
6048718d	150	unsigned int i, num_pages;
fceaf24a HJ	151
	152	DPRINT_ENTER(NETVSC_DRV);
	153
02fafbc6 GKH	154	DPRINT_DBG(NETVSC_DRV, "xmit packet - len %d data_len %d",
02fafbc6 GKH	155	skb->len, skb->data_len);
fceaf24a	156
6048718d SH	157	/* Add 1 for skb->data and additional one for RNDIS */
6048718d SH	158	num_pages = skb_shinfo(skb)->nr_frags + 1 + 1;
b220f5f9 SH	159	if (num_pages > net_device_ctx->avail)
b220f5f9 SH	160	return NETDEV_TX_BUSY;
fceaf24a	161
454f18a9	162	/* Allocate a netvsc packet based on # of frags. */
02fafbc6	163	packet = kzalloc(sizeof(struct hv_netvsc_packet) +
6048718d	164	(num_pages * sizeof(struct hv_page_buffer)) +
02fafbc6 GKH	165	net_drv_obj->RequestExtSize, GFP_ATOMIC);
02fafbc6 GKH	166	if (!packet) {
b220f5f9	167	/* out of memory, silently drop packet */
4193d4f4	168	DPRINT_ERR(NETVSC_DRV, "unable to allocate hv_netvsc_packet");
b220f5f9 SH	169
	170	dev_kfree_skb(skb);
	171	net->stats.tx_dropped++;
	172	return NETDEV_TX_OK;
fceaf24a HJ	173	}
fceaf24a HJ	174
02fafbc6 GKH	175	packet->Extension = (void *)(unsigned long)packet +
02fafbc6 GKH	176	sizeof(struct hv_netvsc_packet) +
6048718d	177	(num_pages * sizeof(struct hv_page_buffer));
fceaf24a	178
454f18a9	179	/* Setup the rndis header */
6048718d	180	packet->PageBufferCount = num_pages;
fceaf24a	181
454f18a9 BP	182	/* TODO: Flush all write buffers/ memory fence ??? */
454f18a9 BP	183	/* wmb(); */
fceaf24a	184
454f18a9	185	/* Initialize it from the skb */
fceaf24a HJ	186	packet->TotalDataBufferLength = skb->len;
fceaf24a HJ	187
6048718d SH	188	/* Start filling in the page buffers starting after RNDIS buffer. */
	189	packet->PageBuffers[1].Pfn = virt_to_phys(skb->data) >> PAGE_SHIFT;
	190	packet->PageBuffers[1].Offset
	191	= (unsigned long)skb->data & (PAGE_SIZE - 1);
	192	packet->PageBuffers[1].Length = skb_headlen(skb);
	193
	194	/* Additional fragments are after SKB data */
	195	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
	196	skb_frag_t *f = &skb_shinfo(skb)->frags[i];
	197
	198	packet->PageBuffers[i+2].Pfn = page_to_pfn(f->page);
	199	packet->PageBuffers[i+2].Offset = f->page_offset;
	200	packet->PageBuffers[i+2].Length = f->size;
fceaf24a HJ	201	}
fceaf24a HJ	202
454f18a9	203	/* Set the completion routine */
fceaf24a HJ	204	packet->Completion.Send.OnSendCompletion = netvsc_xmit_completion;
fceaf24a HJ	205	packet->Completion.Send.SendCompletionContext = packet;
c4b0bc94	206	packet->Completion.Send.SendCompletionTid = (unsigned long)skb;
fceaf24a	207
02fafbc6 GKH	208	ret = net_drv_obj->OnSend(&net_device_ctx->device_ctx->device_obj,
02fafbc6 GKH	209	packet);
02fafbc6	210	if (ret == 0) {
b852fdce SH	211	net->stats.tx_bytes += skb->len;
b852fdce SH	212	net->stats.tx_packets++;
fceaf24a	213
b220f5f9 SH	214	DPRINT_DBG(NETVSC_DRV, "# of xmits %lu total size %lu",
	215	net->stats.tx_packets,
	216	net->stats.tx_bytes);
fceaf24a	217
b220f5f9 SH	218	if ((net_device_ctx->avail -= num_pages) < PACKET_PAGES_LOWATER)
	219	netif_stop_queue(net);
	220	} else {
	221	/* we are shutting down or bus overloaded, just drop packet */
b852fdce	222	net->stats.tx_dropped++;
b220f5f9	223	netvsc_xmit_completion(packet);
fceaf24a HJ	224	}
fceaf24a HJ	225
fceaf24a	226	DPRINT_EXIT(NETVSC_DRV);
b220f5f9	227	return NETDEV_TX_OK;
fceaf24a HJ	228	}
fceaf24a HJ	229
3e189519	230	/*
02fafbc6 GKH	231	* netvsc_linkstatus_callback - Link up/down notification
	232	*/
	233	static void netvsc_linkstatus_callback(struct hv_device *device_obj,
	234	unsigned int status)
fceaf24a	235	{
f916a34d	236	struct vm_device *device_ctx = to_vm_device(device_obj);
02fafbc6	237	struct net_device *net = dev_get_drvdata(&device_ctx->device);
fceaf24a HJ	238
	239	DPRINT_ENTER(NETVSC_DRV);
	240
02fafbc6 GKH	241	if (!net) {
	242	DPRINT_ERR(NETVSC_DRV, "got link status but net device "
	243	"not initialized yet");
fceaf24a HJ	244	return;
	245	}
	246
02fafbc6	247	if (status == 1) {
fceaf24a HJ	248	netif_carrier_on(net);
fceaf24a HJ	249	netif_wake_queue(net);
02fafbc6	250	} else {
fceaf24a HJ	251	netif_carrier_off(net);
	252	netif_stop_queue(net);
	253	}
	254	DPRINT_EXIT(NETVSC_DRV);
	255	}
	256
3e189519 HJ	257	/*
	258	* netvsc_recv_callback - Callback when we receive a packet from the
	259	* "wire" on the specified device.
02fafbc6 GKH	260	*/
	261	static int netvsc_recv_callback(struct hv_device *device_obj,
	262	struct hv_netvsc_packet *packet)
fceaf24a	263	{
f916a34d	264	struct vm_device *device_ctx = to_vm_device(device_obj);
621d7fb7	265	struct net_device *net = dev_get_drvdata(&device_ctx->device);
fceaf24a HJ	266	struct sk_buff *skb;
fceaf24a HJ	267	void *data;
02fafbc6	268	int i;
fceaf24a HJ	269	unsigned long flags;
	270
	271	DPRINT_ENTER(NETVSC_DRV);
	272
02fafbc6 GKH	273	if (!net) {
	274	DPRINT_ERR(NETVSC_DRV, "got receive callback but net device "
	275	"not initialized yet");
fceaf24a HJ	276	return 0;
	277	}
	278
9495c282 SH	279	/* Allocate a skb - TODO direct I/O to pages? */
	280	skb = netdev_alloc_skb_ip_align(net, packet->TotalDataBufferLength);
	281	if (unlikely(!skb)) {
	282	++net->stats.rx_dropped;
	283	return 0;
	284	}
fceaf24a	285
454f18a9	286	/* for kmap_atomic */
fceaf24a HJ	287	local_irq_save(flags);
fceaf24a HJ	288
02fafbc6 GKH	289	/*
	290	* Copy to skb. This copy is needed here since the memory pointed by
	291	* hv_netvsc_packet cannot be deallocated
	292	*/
	293	for (i = 0; i < packet->PageBufferCount; i++) {
	294	data = kmap_atomic(pfn_to_page(packet->PageBuffers[i].Pfn),
	295	KM_IRQ1);
	296	data = (void *)(unsigned long)data +
	297	packet->PageBuffers[i].Offset;
	298
	299	memcpy(skb_put(skb, packet->PageBuffers[i].Length), data,
	300	packet->PageBuffers[i].Length);
	301
	302	kunmap_atomic((void *)((unsigned long)data -
	303	packet->PageBuffers[i].Offset), KM_IRQ1);
fceaf24a HJ	304	}
	305
	306	local_irq_restore(flags);
	307
	308	skb->protocol = eth_type_trans(skb, net);
fceaf24a HJ	309	skb->ip_summed = CHECKSUM_NONE;
fceaf24a HJ	310
9495c282 SH	311	net->stats.rx_packets++;
	312	net->stats.rx_bytes += skb->len;
	313
02fafbc6 GKH	314	/*
02fafbc6 GKH	315	* Pass the skb back up. Network stack will deallocate the skb when it
9495c282 SH	316	* is done.
9495c282 SH	317	* TODO - use NAPI?
02fafbc6	318	*/
9495c282	319	netif_rx(skb);
fceaf24a	320
02fafbc6	321	DPRINT_DBG(NETVSC_DRV, "# of recvs %lu total size %lu",
b852fdce	322	net->stats.rx_packets, net->stats.rx_bytes);
fceaf24a HJ	323
	324	DPRINT_EXIT(NETVSC_DRV);
	325
	326	return 0;
	327	}
	328
df2fff28 GKH	329	static const struct net_device_ops device_ops = {
	330	.ndo_open = netvsc_open,
	331	.ndo_stop = netvsc_close,
	332	.ndo_start_xmit = netvsc_start_xmit,
df2fff28 GKH	333	.ndo_set_multicast_list = netvsc_set_multicast_list,
	334	};
	335
	336	static int netvsc_probe(struct device *device)
	337	{
	338	struct driver_context *driver_ctx =
	339	driver_to_driver_context(device->driver);
	340	struct netvsc_driver_context *net_drv_ctx =
	341	(struct netvsc_driver_context *)driver_ctx;
	342	struct netvsc_driver *net_drv_obj = &net_drv_ctx->drv_obj;
f916a34d	343	struct vm_device *device_ctx = device_to_vm_device(device);
df2fff28 GKH	344	struct hv_device *device_obj = &device_ctx->device_obj;
	345	struct net_device *net = NULL;
	346	struct net_device_context *net_device_ctx;
	347	struct netvsc_device_info device_info;
	348	int ret;
	349
	350	DPRINT_ENTER(NETVSC_DRV);
	351
	352	if (!net_drv_obj->Base.OnDeviceAdd)
	353	return -1;
	354
	355	net = alloc_netdev(sizeof(struct net_device_context), "seth%d",
	356	ether_setup);
	357	if (!net)
	358	return -1;
	359
	360	/* Set initial state */
	361	netif_carrier_off(net);
	362	netif_stop_queue(net);
	363
	364	net_device_ctx = netdev_priv(net);
	365	net_device_ctx->device_ctx = device_ctx;
b220f5f9	366	net_device_ctx->avail = ring_size;
df2fff28 GKH	367	dev_set_drvdata(device, net);
	368
	369	/* Notify the netvsc driver of the new device */
	370	ret = net_drv_obj->Base.OnDeviceAdd(device_obj, &device_info);
	371	if (ret != 0) {
	372	free_netdev(net);
	373	dev_set_drvdata(device, NULL);
	374
	375	DPRINT_ERR(NETVSC_DRV, "unable to add netvsc device (ret %d)",
	376	ret);
	377	return ret;
	378	}
	379
	380	/*
	381	* If carrier is still off ie we did not get a link status callback,
	382	* update it if necessary
	383	*/
	384	/*
	385	* FIXME: We should use a atomic or test/set instead to avoid getting
	386	* out of sync with the device's link status
	387	*/
	388	if (!netif_carrier_ok(net))
	389	if (!device_info.LinkState)
	390	netif_carrier_on(net);
	391
	392	memcpy(net->dev_addr, device_info.MacAddr, ETH_ALEN);
	393
	394	net->netdev_ops = &device_ops;
	395
6048718d SH	396	/* TODO: Add GSO and Checksum offload */
	397	net->features = NETIF_F_SG;
	398
df2fff28 GKH	399	SET_NETDEV_DEV(net, device);
	400
	401	ret = register_netdev(net);
	402	if (ret != 0) {
	403	/* Remove the device and release the resource */
	404	net_drv_obj->Base.OnDeviceRemove(device_obj);
	405	free_netdev(net);
	406	}
	407
	408	DPRINT_EXIT(NETVSC_DRV);
	409	return ret;
	410	}
	411
	412	static int netvsc_remove(struct device *device)
	413	{
	414	struct driver_context *driver_ctx =
	415	driver_to_driver_context(device->driver);
	416	struct netvsc_driver_context *net_drv_ctx =
	417	(struct netvsc_driver_context *)driver_ctx;
	418	struct netvsc_driver *net_drv_obj = &net_drv_ctx->drv_obj;
f916a34d	419	struct vm_device *device_ctx = device_to_vm_device(device);
df2fff28 GKH	420	struct net_device *net = dev_get_drvdata(&device_ctx->device);
	421	struct hv_device *device_obj = &device_ctx->device_obj;
	422	int ret;
	423
	424	DPRINT_ENTER(NETVSC_DRV);
	425
	426	if (net == NULL) {
	427	DPRINT_INFO(NETVSC, "no net device to remove");
	428	DPRINT_EXIT(NETVSC_DRV);
	429	return 0;
	430	}
	431
	432	if (!net_drv_obj->Base.OnDeviceRemove) {
	433	DPRINT_EXIT(NETVSC_DRV);
	434	return -1;
	435	}
	436
	437	/* Stop outbound asap */
	438	netif_stop_queue(net);
	439	/* netif_carrier_off(net); */
	440
	441	unregister_netdev(net);
	442
	443	/*
	444	* Call to the vsc driver to let it know that the device is being
	445	* removed
	446	*/
	447	ret = net_drv_obj->Base.OnDeviceRemove(device_obj);
	448	if (ret != 0) {
	449	/* TODO: */
	450	DPRINT_ERR(NETVSC, "unable to remove vsc device (ret %d)", ret);
	451	}
	452
	453	free_netdev(net);
	454	DPRINT_EXIT(NETVSC_DRV);
	455	return ret;
	456	}
	457
fceaf24a HJ	458	static int netvsc_drv_exit_cb(struct device dev, void data)
	459	{
	460	struct device curr = (struct device )data;
02fafbc6	461
fceaf24a	462	*curr = dev;
02fafbc6 GKH	463	/* stop iterating */
02fafbc6 GKH	464	return 1;
fceaf24a HJ	465	}
fceaf24a HJ	466
bd1de709	467	static void netvsc_drv_exit(void)
fceaf24a	468	{
02fafbc6 GKH	469	struct netvsc_driver *netvsc_drv_obj = &g_netvsc_drv.drv_obj;
	470	struct driver_context *drv_ctx = &g_netvsc_drv.drv_ctx;
	471	struct device *current_dev;
2295ba2e	472	int ret;
fceaf24a HJ	473
	474	DPRINT_ENTER(NETVSC_DRV);
	475
02fafbc6	476	while (1) {
fceaf24a HJ	477	current_dev = NULL;
fceaf24a HJ	478
454f18a9	479	/* Get the device */
2295ba2e	480	ret = driver_for_each_device(&drv_ctx->driver, NULL,
02fafbc6	481	&current_dev, netvsc_drv_exit_cb);
2295ba2e BP	482	if (ret)
	483	DPRINT_WARN(NETVSC_DRV,
	484	"driver_for_each_device returned %d", ret);
	485
fceaf24a HJ	486	if (current_dev == NULL)
	487	break;
	488
454f18a9	489	/* Initiate removal from the top-down */
02fafbc6 GKH	490	DPRINT_INFO(NETVSC_DRV, "unregistering device (%p)...",
02fafbc6 GKH	491	current_dev);
fceaf24a HJ	492
	493	device_unregister(current_dev);
	494	}
	495
	496	if (netvsc_drv_obj->Base.OnCleanup)
	497	netvsc_drv_obj->Base.OnCleanup(&netvsc_drv_obj->Base);
	498
	499	vmbus_child_driver_unregister(drv_ctx);
	500
	501	DPRINT_EXIT(NETVSC_DRV);
	502
	503	return;
	504	}
	505
21707bed	506	static int netvsc_drv_init(int (drv_init)(struct hv_driver drv))
df2fff28 GKH	507	{
	508	struct netvsc_driver *net_drv_obj = &g_netvsc_drv.drv_obj;
	509	struct driver_context *drv_ctx = &g_netvsc_drv.drv_ctx;
	510	int ret;
	511
	512	DPRINT_ENTER(NETVSC_DRV);
	513
	514	vmbus_get_interface(&net_drv_obj->Base.VmbusChannelInterface);
	515
450d7a4b	516	net_drv_obj->RingBufferSize = ring_size * PAGE_SIZE;
df2fff28 GKH	517	net_drv_obj->OnReceiveCallback = netvsc_recv_callback;
	518	net_drv_obj->OnLinkStatusChanged = netvsc_linkstatus_callback;
	519
	520	/* Callback to client driver to complete the initialization */
21707bed	521	drv_init(&net_drv_obj->Base);
df2fff28 GKH	522
	523	drv_ctx->driver.name = net_drv_obj->Base.name;
	524	memcpy(&drv_ctx->class_id, &net_drv_obj->Base.deviceType,
	525	sizeof(struct hv_guid));
	526
	527	drv_ctx->probe = netvsc_probe;
	528	drv_ctx->remove = netvsc_remove;
	529
	530	/* The driver belongs to vmbus */
	531	ret = vmbus_child_driver_register(drv_ctx);
	532
	533	DPRINT_EXIT(NETVSC_DRV);
	534
	535	return ret;
	536	}
	537
fceaf24a HJ	538	static int __init netvsc_init(void)
	539	{
	540	int ret;
	541
	542	DPRINT_ENTER(NETVSC_DRV);
	543	DPRINT_INFO(NETVSC_DRV, "Netvsc initializing....");
	544
	545	ret = netvsc_drv_init(NetVscInitialize);
	546
	547	DPRINT_EXIT(NETVSC_DRV);
	548
	549	return ret;
	550	}
	551
	552	static void __exit netvsc_exit(void)
	553	{
	554	DPRINT_ENTER(NETVSC_DRV);
fceaf24a	555	netvsc_drv_exit();
fceaf24a HJ	556	DPRINT_EXIT(NETVSC_DRV);
	557	}
	558
26c14cc1 HJ	559	MODULE_LICENSE("GPL");
26c14cc1 HJ	560	MODULE_VERSION(HV_DRV_VERSION);
7880fc54	561	MODULE_DESCRIPTION("Microsoft Hyper-V network driver");
fceaf24a HJ	562
	563	module_init(netvsc_init);
	564	module_exit(netvsc_exit);