[thirdparty/linux.git] / drivers / net / vsockmon.c

// SPDX-License-Identifier: GPL-2.0-only
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/if_arp.h>
#include <net/rtnetlink.h>
#include <net/sock.h>
#include <net/af_vsock.h>
#include <uapi/linux/vsockmon.h>
#include <linux/virtio_vsock.h>

/* Virtio transport max packet size plus header */
#define DEFAULT_MTU (VIRTIO_VSOCK_MAX_PKT_BUF_SIZE + \
		     sizeof(struct af_vsockmon_hdr))

static int vsockmon_dev_init(struct net_device *dev)
{
	dev->lstats = netdev_alloc_pcpu_stats(struct pcpu_lstats);
	if (!dev->lstats)
		return -ENOMEM;
	return 0;
}

static void vsockmon_dev_uninit(struct net_device *dev)
{
	free_percpu(dev->lstats);
}

struct vsockmon {
	struct vsock_tap vt;
};

static int vsockmon_open(struct net_device *dev)
{
	struct vsockmon *vsockmon = netdev_priv(dev);

	vsockmon->vt.dev = dev;
	vsockmon->vt.module = THIS_MODULE;
	return vsock_add_tap(&vsockmon->vt);
}

static int vsockmon_close(struct net_device *dev)
{
	struct vsockmon *vsockmon = netdev_priv(dev);

	return vsock_remove_tap(&vsockmon->vt);
}

static netdev_tx_t vsockmon_xmit(struct sk_buff *skb, struct net_device *dev)
{
	int len = skb->len;
	struct pcpu_lstats *stats = this_cpu_ptr(dev->lstats);

	u64_stats_update_begin(&stats->syncp);
	stats->bytes += len;
	stats->packets++;
	u64_stats_update_end(&stats->syncp);

	dev_kfree_skb(skb);

	return NETDEV_TX_OK;
}

static void
vsockmon_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats)
{
	int i;
	u64 bytes = 0, packets = 0;

	for_each_possible_cpu(i) {
		const struct pcpu_lstats *vstats;
		u64 tbytes, tpackets;
		unsigned int start;

		vstats = per_cpu_ptr(dev->lstats, i);

		do {
			start = u64_stats_fetch_begin_irq(&vstats->syncp);
			tbytes = vstats->bytes;
			tpackets = vstats->packets;
		} while (u64_stats_fetch_retry_irq(&vstats->syncp, start));

		packets += tpackets;
		bytes += tbytes;
	}

	stats->rx_packets = packets;
	stats->tx_packets = 0;

	stats->rx_bytes = bytes;
	stats->tx_bytes = 0;
}

static int vsockmon_is_valid_mtu(int new_mtu)
{
	return new_mtu >= (int)sizeof(struct af_vsockmon_hdr);
}

static int vsockmon_change_mtu(struct net_device *dev, int new_mtu)
{
	if (!vsockmon_is_valid_mtu(new_mtu))
		return -EINVAL;

	dev->mtu = new_mtu;
	return 0;
}

static const struct net_device_ops vsockmon_ops = {
	.ndo_init = vsockmon_dev_init,
	.ndo_uninit = vsockmon_dev_uninit,
	.ndo_open = vsockmon_open,
	.ndo_stop = vsockmon_close,
	.ndo_start_xmit = vsockmon_xmit,
	.ndo_get_stats64 = vsockmon_get_stats64,
	.ndo_change_mtu = vsockmon_change_mtu,
};

static u32 always_on(struct net_device *dev)
{
	return 1;
}

static const struct ethtool_ops vsockmon_ethtool_ops = {
	.get_link = always_on,
};

static void vsockmon_setup(struct net_device *dev)
{
	dev->type = ARPHRD_VSOCKMON;
	dev->priv_flags |= IFF_NO_QUEUE;

	dev->netdev_ops	= &vsockmon_ops;
	dev->ethtool_ops = &vsockmon_ethtool_ops;
	dev->needs_free_netdev = true;

	dev->features = NETIF_F_SG | NETIF_F_FRAGLIST |
			NETIF_F_HIGHDMA | NETIF_F_LLTX;

	dev->flags = IFF_NOARP;

	dev->mtu = DEFAULT_MTU;
}

static struct rtnl_link_ops vsockmon_link_ops __read_mostly = {
	.kind			= "vsockmon",
	.priv_size		= sizeof(struct vsockmon),
	.setup			= vsockmon_setup,
};

static __init int vsockmon_register(void)
{
	return rtnl_link_register(&vsockmon_link_ops);
}

static __exit void vsockmon_unregister(void)
{
	rtnl_link_unregister(&vsockmon_link_ops);
}

module_init(vsockmon_register);
module_exit(vsockmon_unregister);

MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Gerard Garcia <ggarcia@deic.uab.cat>");
MODULE_DESCRIPTION("Vsock monitoring device. Based on nlmon device.");
MODULE_ALIAS_RTNL_LINK("vsockmon");
Commit	Line	Data
09c434b8	1	// SPDX-License-Identifier: GPL-2.0-only
0b2e6644 GG	2	#include <linux/module.h>
	3	#include <linux/kernel.h>
	4	#include <linux/if_arp.h>
	5	#include <net/rtnetlink.h>
	6	#include <net/sock.h>
	7	#include <net/af_vsock.h>
	8	#include <uapi/linux/vsockmon.h>
	9	#include <linux/virtio_vsock.h>
	10
	11	/* Virtio transport max packet size plus header */
	12	#define DEFAULT_MTU (VIRTIO_VSOCK_MAX_PKT_BUF_SIZE + \
	13	sizeof(struct af_vsockmon_hdr))
	14
0b2e6644 GG	15	static int vsockmon_dev_init(struct net_device *dev)
	16	{
	17	dev->lstats = netdev_alloc_pcpu_stats(struct pcpu_lstats);
	18	if (!dev->lstats)
	19	return -ENOMEM;
	20	return 0;
	21	}
	22
	23	static void vsockmon_dev_uninit(struct net_device *dev)
	24	{
	25	free_percpu(dev->lstats);
	26	}
	27
	28	struct vsockmon {
	29	struct vsock_tap vt;
	30	};
	31
	32	static int vsockmon_open(struct net_device *dev)
	33	{
	34	struct vsockmon *vsockmon = netdev_priv(dev);
	35
	36	vsockmon->vt.dev = dev;
	37	vsockmon->vt.module = THIS_MODULE;
	38	return vsock_add_tap(&vsockmon->vt);
	39	}
	40
	41	static int vsockmon_close(struct net_device *dev)
	42	{
	43	struct vsockmon *vsockmon = netdev_priv(dev);
	44
	45	return vsock_remove_tap(&vsockmon->vt);
	46	}
	47
	48	static netdev_tx_t vsockmon_xmit(struct sk_buff skb, struct net_device dev)
	49	{
	50	int len = skb->len;
	51	struct pcpu_lstats *stats = this_cpu_ptr(dev->lstats);
	52
	53	u64_stats_update_begin(&stats->syncp);
52bb6677 LR	54	stats->bytes += len;
52bb6677 LR	55	stats->packets++;
0b2e6644 GG	56	u64_stats_update_end(&stats->syncp);
	57
	58	dev_kfree_skb(skb);
	59
	60	return NETDEV_TX_OK;
	61	}
	62
	63	static void
	64	vsockmon_get_stats64(struct net_device dev, struct rtnl_link_stats64 stats)
	65	{
	66	int i;
	67	u64 bytes = 0, packets = 0;
	68
	69	for_each_possible_cpu(i) {
	70	const struct pcpu_lstats *vstats;
	71	u64 tbytes, tpackets;
	72	unsigned int start;
	73
	74	vstats = per_cpu_ptr(dev->lstats, i);
	75
	76	do {
	77	start = u64_stats_fetch_begin_irq(&vstats->syncp);
52bb6677 LR	78	tbytes = vstats->bytes;
52bb6677 LR	79	tpackets = vstats->packets;
0b2e6644 GG	80	} while (u64_stats_fetch_retry_irq(&vstats->syncp, start));
	81
	82	packets += tpackets;
	83	bytes += tbytes;
	84	}
	85
	86	stats->rx_packets = packets;
	87	stats->tx_packets = 0;
	88
	89	stats->rx_bytes = bytes;
	90	stats->tx_bytes = 0;
	91	}
	92
	93	static int vsockmon_is_valid_mtu(int new_mtu)
	94	{
	95	return new_mtu >= (int)sizeof(struct af_vsockmon_hdr);
	96	}
	97
	98	static int vsockmon_change_mtu(struct net_device *dev, int new_mtu)
	99	{
	100	if (!vsockmon_is_valid_mtu(new_mtu))
	101	return -EINVAL;
	102
	103	dev->mtu = new_mtu;
	104	return 0;
	105	}
	106
	107	static const struct net_device_ops vsockmon_ops = {
	108	.ndo_init = vsockmon_dev_init,
	109	.ndo_uninit = vsockmon_dev_uninit,
	110	.ndo_open = vsockmon_open,
	111	.ndo_stop = vsockmon_close,
	112	.ndo_start_xmit = vsockmon_xmit,
	113	.ndo_get_stats64 = vsockmon_get_stats64,
	114	.ndo_change_mtu = vsockmon_change_mtu,
	115	};
	116
	117	static u32 always_on(struct net_device *dev)
	118	{
	119	return 1;
	120	}
	121
	122	static const struct ethtool_ops vsockmon_ethtool_ops = {
	123	.get_link = always_on,
	124	};
	125
	126	static void vsockmon_setup(struct net_device *dev)
	127	{
	128	dev->type = ARPHRD_VSOCKMON;
	129	dev->priv_flags \|= IFF_NO_QUEUE;
	130
	131	dev->netdev_ops = &vsockmon_ops;
	132	dev->ethtool_ops = &vsockmon_ethtool_ops;
cf124db5	133	dev->needs_free_netdev = true;
0b2e6644 GG	134
	135	dev->features = NETIF_F_SG \| NETIF_F_FRAGLIST \|
	136	NETIF_F_HIGHDMA \| NETIF_F_LLTX;
	137
	138	dev->flags = IFF_NOARP;
	139
	140	dev->mtu = DEFAULT_MTU;
	141	}
	142
	143	static struct rtnl_link_ops vsockmon_link_ops __read_mostly = {
	144	.kind = "vsockmon",
	145	.priv_size = sizeof(struct vsockmon),
	146	.setup = vsockmon_setup,
	147	};
	148
	149	static __init int vsockmon_register(void)
	150	{
	151	return rtnl_link_register(&vsockmon_link_ops);
	152	}
	153
	154	static __exit void vsockmon_unregister(void)
	155	{
	156	rtnl_link_unregister(&vsockmon_link_ops);
	157	}
	158
	159	module_init(vsockmon_register);
	160	module_exit(vsockmon_unregister);
	161
	162	MODULE_LICENSE("GPL v2");
	163	MODULE_AUTHOR("Gerard Garcia <ggarcia@deic.uab.cat>");
	164	MODULE_DESCRIPTION("Vsock monitoring device. Based on nlmon device.");
	165	MODULE_ALIAS_RTNL_LINK("vsockmon");