diff options
Diffstat (limited to 'net/vmw_vsock/vsock_loopback.c')
| -rw-r--r-- | net/vmw_vsock/vsock_loopback.c | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/net/vmw_vsock/vsock_loopback.c b/net/vmw_vsock/vsock_loopback.c new file mode 100644 index 000000000..a45f7ffca --- /dev/null +++ b/net/vmw_vsock/vsock_loopback.c @@ -0,0 +1,180 @@ +// 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; + + spinlock_t pkt_list_lock; /* protects pkt_list */ + struct list_head pkt_list; + 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 virtio_vsock_pkt *pkt) +{ + struct vsock_loopback *vsock = &the_vsock_loopback; + int len = pkt->len; + + spin_lock_bh(&vsock->pkt_list_lock); + list_add_tail(&pkt->list, &vsock->pkt_list); + spin_unlock_bh(&vsock->pkt_list_lock); + + 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; + struct virtio_vsock_pkt *pkt, *n; + LIST_HEAD(freeme); + + spin_lock_bh(&vsock->pkt_list_lock); + list_for_each_entry_safe(pkt, n, &vsock->pkt_list, list) { + if (pkt->vsk != vsk) + continue; + list_move(&pkt->list, &freeme); + } + spin_unlock_bh(&vsock->pkt_list_lock); + + list_for_each_entry_safe(pkt, n, &freeme, list) { + list_del(&pkt->list); + virtio_transport_free_pkt(pkt); + } + + return 0; +} + +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, + + .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, + }, + + .send_pkt = vsock_loopback_send_pkt, +}; + +static void vsock_loopback_work(struct work_struct *work) +{ + struct vsock_loopback *vsock = + container_of(work, struct vsock_loopback, pkt_work); + LIST_HEAD(pkts); + + spin_lock_bh(&vsock->pkt_list_lock); + list_splice_init(&vsock->pkt_list, &pkts); + spin_unlock_bh(&vsock->pkt_list_lock); + + while (!list_empty(&pkts)) { + struct virtio_vsock_pkt *pkt; + + pkt = list_first_entry(&pkts, struct virtio_vsock_pkt, list); + list_del_init(&pkt->list); + + virtio_transport_deliver_tap_pkt(pkt); + virtio_transport_recv_pkt(&loopback_transport, pkt); + } +} + +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; + + spin_lock_init(&vsock->pkt_list_lock); + INIT_LIST_HEAD(&vsock->pkt_list); + 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; + struct virtio_vsock_pkt *pkt; + + vsock_core_unregister(&loopback_transport.transport); + + flush_work(&vsock->pkt_work); + + spin_lock_bh(&vsock->pkt_list_lock); + while (!list_empty(&vsock->pkt_list)) { + pkt = list_first_entry(&vsock->pkt_list, + struct virtio_vsock_pkt, list); + list_del(&pkt->list); + virtio_transport_free_pkt(pkt); + } + spin_unlock_bh(&vsock->pkt_list_lock); + + 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); |