[linux-block.git] / net / vmw_vsock / vsock_loopback.c

// SPDX-License-Identifier: GPL-2.0-only
/* loopback transport for vsock using virtio_transport_common APIs
 *
 * Copyright (C) 2013-2019 Red Hat, Inc.
 * Authors: Asias He <asias@redhat.com>
 *          Stefan Hajnoczi <stefanha@redhat.com>
 *          Stefano Garzarella <sgarzare@redhat.com>
 *
 */
#include <linux/spinlock.h>
#include <linux/module.h>
#include <linux/list.h>
#include <linux/virtio_vsock.h>

struct vsock_loopback {
	struct workqueue_struct *workqueue;

	struct sk_buff_head pkt_queue;
	struct work_struct pkt_work;
};

static struct vsock_loopback the_vsock_loopback;

static u32 vsock_loopback_get_local_cid(void)
{
	return VMADDR_CID_LOCAL;
}

static int vsock_loopback_send_pkt(struct sk_buff *skb)
{
	struct vsock_loopback *vsock = &the_vsock_loopback;
	int len = skb->len;

	virtio_vsock_skb_queue_tail(&vsock->pkt_queue, skb);
	queue_work(vsock->workqueue, &vsock->pkt_work);

	return len;
}

static int vsock_loopback_cancel_pkt(struct vsock_sock *vsk)
{
	struct vsock_loopback *vsock = &the_vsock_loopback;

	virtio_transport_purge_skbs(vsk, &vsock->pkt_queue);

	return 0;
}

static bool vsock_loopback_seqpacket_allow(u32 remote_cid);

static struct virtio_transport loopback_transport = {
	.transport = {
		.module                   = THIS_MODULE,

		.get_local_cid            = vsock_loopback_get_local_cid,

		.init                     = virtio_transport_do_socket_init,
		.destruct                 = virtio_transport_destruct,
		.release                  = virtio_transport_release,
		.connect                  = virtio_transport_connect,
		.shutdown                 = virtio_transport_shutdown,
		.cancel_pkt               = vsock_loopback_cancel_pkt,

		.dgram_bind               = virtio_transport_dgram_bind,
		.dgram_dequeue            = virtio_transport_dgram_dequeue,
		.dgram_enqueue            = virtio_transport_dgram_enqueue,
		.dgram_allow              = virtio_transport_dgram_allow,

		.stream_dequeue           = virtio_transport_stream_dequeue,
		.stream_enqueue           = virtio_transport_stream_enqueue,
		.stream_has_data          = virtio_transport_stream_has_data,
		.stream_has_space         = virtio_transport_stream_has_space,
		.stream_rcvhiwat          = virtio_transport_stream_rcvhiwat,
		.stream_is_active         = virtio_transport_stream_is_active,
		.stream_allow             = virtio_transport_stream_allow,

		.seqpacket_dequeue        = virtio_transport_seqpacket_dequeue,
		.seqpacket_enqueue        = virtio_transport_seqpacket_enqueue,
		.seqpacket_allow          = vsock_loopback_seqpacket_allow,
		.seqpacket_has_data       = virtio_transport_seqpacket_has_data,

		.notify_poll_in           = virtio_transport_notify_poll_in,
		.notify_poll_out          = virtio_transport_notify_poll_out,
		.notify_recv_init         = virtio_transport_notify_recv_init,
		.notify_recv_pre_block    = virtio_transport_notify_recv_pre_block,
		.notify_recv_pre_dequeue  = virtio_transport_notify_recv_pre_dequeue,
		.notify_recv_post_dequeue = virtio_transport_notify_recv_post_dequeue,
		.notify_send_init         = virtio_transport_notify_send_init,
		.notify_send_pre_block    = virtio_transport_notify_send_pre_block,
		.notify_send_pre_enqueue  = virtio_transport_notify_send_pre_enqueue,
		.notify_send_post_enqueue = virtio_transport_notify_send_post_enqueue,
		.notify_buffer_size       = virtio_transport_notify_buffer_size,

		.read_skb = virtio_transport_read_skb,
	},

	.send_pkt = vsock_loopback_send_pkt,
};

static bool vsock_loopback_seqpacket_allow(u32 remote_cid)
{
	return true;
}

static void vsock_loopback_work(struct work_struct *work)
{
	struct vsock_loopback *vsock =
		container_of(work, struct vsock_loopback, pkt_work);
	struct sk_buff_head pkts;
	struct sk_buff *skb;

	skb_queue_head_init(&pkts);

	spin_lock_bh(&vsock->pkt_queue.lock);
	skb_queue_splice_init(&vsock->pkt_queue, &pkts);
	spin_unlock_bh(&vsock->pkt_queue.lock);

	while ((skb = __skb_dequeue(&pkts))) {
		virtio_transport_deliver_tap_pkt(skb);
		virtio_transport_recv_pkt(&loopback_transport, skb);
	}
}

static int __init vsock_loopback_init(void)
{
	struct vsock_loopback *vsock = &the_vsock_loopback;
	int ret;

	vsock->workqueue = alloc_workqueue("vsock-loopback", 0, 0);
	if (!vsock->workqueue)
		return -ENOMEM;

	skb_queue_head_init(&vsock->pkt_queue);
	INIT_WORK(&vsock->pkt_work, vsock_loopback_work);

	ret = vsock_core_register(&loopback_transport.transport,
				  VSOCK_TRANSPORT_F_LOCAL);
	if (ret)
		goto out_wq;

	return 0;

out_wq:
	destroy_workqueue(vsock->workqueue);
	return ret;
}

static void __exit vsock_loopback_exit(void)
{
	struct vsock_loopback *vsock = &the_vsock_loopback;

	vsock_core_unregister(&loopback_transport.transport);

	flush_work(&vsock->pkt_work);

	virtio_vsock_skb_queue_purge(&vsock->pkt_queue);

	destroy_workqueue(vsock->workqueue);
}

module_init(vsock_loopback_init);
module_exit(vsock_loopback_exit);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Stefano Garzarella <sgarzare@redhat.com>");
MODULE_DESCRIPTION("loopback transport for vsock");
MODULE_ALIAS_NETPROTO(PF_VSOCK);
Commit	Line	Data
077263fb SG	1	// SPDX-License-Identifier: GPL-2.0-only
	2	/* loopback transport for vsock using virtio_transport_common APIs
	3	*
	4	* Copyright (C) 2013-2019 Red Hat, Inc.
	5	* Authors: Asias He <asias@redhat.com>
	6	* Stefan Hajnoczi <stefanha@redhat.com>
	7	* Stefano Garzarella <sgarzare@redhat.com>
	8	*
	9	*/
	10	#include <linux/spinlock.h>
	11	#include <linux/module.h>
	12	#include <linux/list.h>
	13	#include <linux/virtio_vsock.h>
	14
	15	struct vsock_loopback {
	16	struct workqueue_struct *workqueue;
	17
71dc9ec9	18	struct sk_buff_head pkt_queue;
077263fb SG	19	struct work_struct pkt_work;
	20	};
	21
	22	static struct vsock_loopback the_vsock_loopback;
	23
	24	static u32 vsock_loopback_get_local_cid(void)
	25	{
	26	return VMADDR_CID_LOCAL;
	27	}
	28
71dc9ec9	29	static int vsock_loopback_send_pkt(struct sk_buff *skb)
077263fb SG	30	{
077263fb SG	31	struct vsock_loopback *vsock = &the_vsock_loopback;
71dc9ec9	32	int len = skb->len;
077263fb	33
eaaa4e92	34	virtio_vsock_skb_queue_tail(&vsock->pkt_queue, skb);
077263fb SG	35	queue_work(vsock->workqueue, &vsock->pkt_work);
	36
	37	return len;
	38	}
	39
	40	static int vsock_loopback_cancel_pkt(struct vsock_sock *vsk)
	41	{
	42	struct vsock_loopback *vsock = &the_vsock_loopback;
077263fb	43
71dc9ec9	44	virtio_transport_purge_skbs(vsk, &vsock->pkt_queue);
077263fb SG	45
	46	return 0;
	47	}
	48
6e90a577 AK	49	static bool vsock_loopback_seqpacket_allow(u32 remote_cid);
6e90a577 AK	50
077263fb SG	51	static struct virtio_transport loopback_transport = {
	52	.transport = {
	53	.module = THIS_MODULE,
	54
	55	.get_local_cid = vsock_loopback_get_local_cid,
	56
	57	.init = virtio_transport_do_socket_init,
	58	.destruct = virtio_transport_destruct,
	59	.release = virtio_transport_release,
	60	.connect = virtio_transport_connect,
	61	.shutdown = virtio_transport_shutdown,
	62	.cancel_pkt = vsock_loopback_cancel_pkt,
	63
	64	.dgram_bind = virtio_transport_dgram_bind,
	65	.dgram_dequeue = virtio_transport_dgram_dequeue,
	66	.dgram_enqueue = virtio_transport_dgram_enqueue,
	67	.dgram_allow = virtio_transport_dgram_allow,
	68
	69	.stream_dequeue = virtio_transport_stream_dequeue,
	70	.stream_enqueue = virtio_transport_stream_enqueue,
	71	.stream_has_data = virtio_transport_stream_has_data,
	72	.stream_has_space = virtio_transport_stream_has_space,
	73	.stream_rcvhiwat = virtio_transport_stream_rcvhiwat,
	74	.stream_is_active = virtio_transport_stream_is_active,
	75	.stream_allow = virtio_transport_stream_allow,
	76
6e90a577 AK	77	.seqpacket_dequeue = virtio_transport_seqpacket_dequeue,
	78	.seqpacket_enqueue = virtio_transport_seqpacket_enqueue,
	79	.seqpacket_allow = vsock_loopback_seqpacket_allow,
	80	.seqpacket_has_data = virtio_transport_seqpacket_has_data,
	81
077263fb SG	82	.notify_poll_in = virtio_transport_notify_poll_in,
	83	.notify_poll_out = virtio_transport_notify_poll_out,
	84	.notify_recv_init = virtio_transport_notify_recv_init,
	85	.notify_recv_pre_block = virtio_transport_notify_recv_pre_block,
	86	.notify_recv_pre_dequeue = virtio_transport_notify_recv_pre_dequeue,
	87	.notify_recv_post_dequeue = virtio_transport_notify_recv_post_dequeue,
	88	.notify_send_init = virtio_transport_notify_send_init,
	89	.notify_send_pre_block = virtio_transport_notify_send_pre_block,
	90	.notify_send_pre_enqueue = virtio_transport_notify_send_pre_enqueue,
	91	.notify_send_post_enqueue = virtio_transport_notify_send_post_enqueue,
	92	.notify_buffer_size = virtio_transport_notify_buffer_size,
634f1a71 BE	93
634f1a71 BE	94	.read_skb = virtio_transport_read_skb,
077263fb SG	95	},
	96
	97	.send_pkt = vsock_loopback_send_pkt,
	98	};
	99
6e90a577 AK	100	static bool vsock_loopback_seqpacket_allow(u32 remote_cid)
	101	{
	102	return true;
	103	}
	104
077263fb SG	105	static void vsock_loopback_work(struct work_struct *work)
	106	{
	107	struct vsock_loopback *vsock =
	108	container_of(work, struct vsock_loopback, pkt_work);
71dc9ec9 BE	109	struct sk_buff_head pkts;
	110	struct sk_buff *skb;
	111
	112	skb_queue_head_init(&pkts);
077263fb	113
b465518d	114	spin_lock_bh(&vsock->pkt_queue.lock);
71dc9ec9	115	skb_queue_splice_init(&vsock->pkt_queue, &pkts);
b465518d	116	spin_unlock_bh(&vsock->pkt_queue.lock);
077263fb	117
71dc9ec9 BE	118	while ((skb = __skb_dequeue(&pkts))) {
	119	virtio_transport_deliver_tap_pkt(skb);
	120	virtio_transport_recv_pkt(&loopback_transport, skb);
077263fb SG	121	}
	122	}
	123
	124	static int __init vsock_loopback_init(void)
	125	{
	126	struct vsock_loopback *vsock = &the_vsock_loopback;
	127	int ret;
	128
	129	vsock->workqueue = alloc_workqueue("vsock-loopback", 0, 0);
	130	if (!vsock->workqueue)
	131	return -ENOMEM;
	132
71dc9ec9	133	skb_queue_head_init(&vsock->pkt_queue);
077263fb SG	134	INIT_WORK(&vsock->pkt_work, vsock_loopback_work);
	135
	136	ret = vsock_core_register(&loopback_transport.transport,
	137	VSOCK_TRANSPORT_F_LOCAL);
	138	if (ret)
	139	goto out_wq;
	140
	141	return 0;
	142
	143	out_wq:
	144	destroy_workqueue(vsock->workqueue);
	145	return ret;
	146	}
	147
	148	static void __exit vsock_loopback_exit(void)
	149	{
	150	struct vsock_loopback *vsock = &the_vsock_loopback;
077263fb SG	151
	152	vsock_core_unregister(&loopback_transport.transport);
	153
	154	flush_work(&vsock->pkt_work);
	155
71dc9ec9	156	virtio_vsock_skb_queue_purge(&vsock->pkt_queue);
077263fb SG	157
	158	destroy_workqueue(vsock->workqueue);
	159	}
	160
	161	module_init(vsock_loopback_init);
	162	module_exit(vsock_loopback_exit);
	163	MODULE_LICENSE("GPL v2");
	164	MODULE_AUTHOR("Stefano Garzarella <sgarzare@redhat.com>");
	165	MODULE_DESCRIPTION("loopback transport for vsock");
	166	MODULE_ALIAS_NETPROTO(PF_VSOCK);