path: root/drivers/net/hyperv/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, see <http://www.gnu.org/licenses/>.
 *
 * Authors:
 *   Haiyang Zhang <haiyangz@microsoft.com>
 *   Hank Janssen  <hjanssen@microsoft.com>
 */
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/init.h>
#include <linux/atomic.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/if_vlan.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 "hyperv_net.h"

#define RING_SIZE_MIN 64
#define LINKCHANGE_INT (2 * HZ)
#define NETVSC_HW_FEATURES	(NETIF_F_RXCSUM | \
				 NETIF_F_SG | \
				 NETIF_F_TSO | \
				 NETIF_F_TSO6 | \
				 NETIF_F_HW_CSUM)
static int ring_size = 128;
module_param(ring_size, int, S_IRUGO);
MODULE_PARM_DESC(ring_size, "Ring buffer size (# of pages)");

static int max_num_vrss_chns = 8;

static const u32 default_msg = NETIF_MSG_DRV | NETIF_MSG_PROBE |
				NETIF_MSG_LINK | NETIF_MSG_IFUP |
				NETIF_MSG_IFDOWN | NETIF_MSG_RX_ERR |
				NETIF_MSG_TX_ERR;

static int debug = -1;
module_param(debug, int, S_IRUGO);
MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");

static void do_set_multicast(struct work_struct *w)
{
	struct net_device_context *ndevctx =
		container_of(w, struct net_device_context, work);
	struct hv_device *device_obj = ndevctx->device_ctx;
	struct net_device *ndev = hv_get_drvdata(device_obj);
	struct netvsc_device *nvdev = ndevctx->nvdev;
	struct rndis_device *rdev;

	if (!nvdev)
		return;

	rdev = nvdev->extension;
	if (rdev == NULL)
		return;

	if (ndev->flags & IFF_PROMISC)
		rndis_filter_set_packet_filter(rdev,
			NDIS_PACKET_TYPE_PROMISCUOUS);
	else
		rndis_filter_set_packet_filter(rdev,
			NDIS_PACKET_TYPE_BROADCAST |
			NDIS_PACKET_TYPE_ALL_MULTICAST |
			NDIS_PACKET_TYPE_DIRECTED);
}

static void netvsc_set_multicast_list(struct net_device *net)
{
	struct net_device_context *net_device_ctx = netdev_priv(net);

	schedule_work(&net_device_ctx->work);
}

static int netvsc_open(struct net_device *net)
{
	struct netvsc_device *nvdev = net_device_to_netvsc_device(net);
	struct rndis_device *rdev;
	int ret = 0;

	netif_carrier_off(net);

	/* Open up the device */
	ret = rndis_filter_open(nvdev);
	if (ret != 0) {
		netdev_err(net, "unable to open device (ret %d).\n", ret);
		return ret;
	}

	netif_tx_wake_all_queues(net);

	rdev = nvdev->extension;
	if (!rdev->link_state)
		netif_carrier_on(net);

	return ret;
}

static int netvsc_close(struct net_device *net)
{
	struct net_device_context *net_device_ctx = netdev_priv(net);
	struct netvsc_device *nvdev = net_device_ctx->nvdev;
	int ret;
	u32 aread, awrite, i, msec = 10, retry = 0, retry_max = 20;
	struct vmbus_channel *chn;

	netif_tx_disable(net);

	/* Make sure netvsc_set_multicast_list doesn't re-enable filter! */
	cancel_work_sync(&net_device_ctx->work);
	ret = rndis_filter_close(nvdev);
	if (ret != 0) {
		netdev_err(net, "unable to close device (ret %d).\n", ret);
		return ret;
	}

	/* Ensure pending bytes in ring are read */
	while (true) {
		aread = 0;
		for (i = 0; i < nvdev->num_chn; i++) {
			chn = nvdev->chn_table[i];
			if (!chn)
				continue;

			hv_get_ringbuffer_availbytes(&chn->inbound, &aread,
						     &awrite);

			if (aread)
				break;

			hv_get_ringbuffer_availbytes(&chn->outbound, &aread,
						     &awrite);

			if (aread)
				break;
		}

		retry++;
		if (retry > retry_max || aread == 0)
			break;

		msleep(msec);

		if (msec < 1000)
			msec *= 2;
	}

	if (aread) {
		netdev_err(net, "Ring buffer not empty after closing rndis\n");
		ret = -ETIMEDOUT;
	}

	return ret;
}

static void *init_ppi_data(struct rndis_message *msg, u32 ppi_size,
				int pkt_type)
{
	struct rndis_packet *rndis_pkt;
	struct rndis_per_packet_info *ppi;

	rndis_pkt = &msg->msg.pkt;
	rndis_pkt->data_offset += ppi_size;

	ppi = (struct rndis_per_packet_info *)((void *)rndis_pkt +
		rndis_pkt->per_pkt_info_offset + rndis_pkt->per_pkt_info_len);

	ppi->size = ppi_size;
	ppi->type = pkt_type;
	ppi->ppi_offset = sizeof(struct rndis_per_packet_info);

	rndis_pkt->per_pkt_info_len += ppi_size;

	return ppi;
}

static u16 netvsc_select_queue(struct net_device *ndev, struct sk_buff *skb,
			void *accel_priv, select_queue_fallback_t fallback)
{
	struct net_device_context *net_device_ctx = netdev_priv(ndev);
	struct netvsc_device *nvsc_dev = net_device_ctx->nvdev;
	u32 hash;
	u16 q_idx = 0;

	if (nvsc_dev == NULL || ndev->real_num_tx_queues <= 1)
		return 0;

	hash = skb_get_hash(skb);
	q_idx = nvsc_dev->send_table[hash % VRSS_SEND_TAB_SIZE] %
		ndev->real_num_tx_queues;

	if (!nvsc_dev->chn_table[q_idx])
		q_idx = 0;

	return q_idx;
}

static u32 fill_pg_buf(struct page *page, u32 offset, u32 len,
			struct hv_page_buffer *pb)
{
	int j = 0;

	/* Deal with compund pages by ignoring unused part
	 * of the page.
	 */
	page += (offset >> PAGE_SHIFT);
	offset &= ~PAGE_MASK;

	while (len > 0) {
		unsigned long bytes;

		bytes = PAGE_SIZE - offset;
		if (bytes > len)
			bytes = len;
		pb[j].pfn = page_to_pfn(page);
		pb[j].offset = offset;
		pb[j].len = bytes;

		offset += bytes;
		len -= bytes;

		if (offset == PAGE_SIZE && len) {
			page++;
			offset = 0;
			j++;
		}
	}

	return j + 1;
}

static u32 init_page_array(void *hdr, u32 len, struct sk_buff *skb,
			   struct hv_netvsc_packet *packet,
			   struct hv_page_buffer **page_buf)
{
	struct hv_page_buffer *pb = *page_buf;
	u32 slots_used = 0;
	char *data = skb->data;
	int frags = skb_shinfo(skb)->nr_frags;
	int i;

	/* The packet is laid out thus:
	 * 1. hdr: RNDIS header and PPI
	 * 2. skb linear data
	 * 3. skb fragment data
	 */
	if (h