From: Bobby Eshleman bobbyeshleman@meta.com
Add NS support to vsock loopback. Sockets in a global mode netns communicate with each other, regardless of namespace. Sockets in a local mode netns may only communicate with other sockets within the same namespace.
Use pernet_ops to install a vsock_loopback for every namespace that is created (to be used if local mode is enabled).
Retroactively call init/exit on every namespace when the vsock_loopback module is loaded in order to initialize the per-ns device.
Signed-off-by: Bobby Eshleman bobbyeshleman@meta.com
--- Changes in v6: - init pernet ops for vsock_loopback module - vsock_loopback: add space in struct to clarify lock protection - do proper cleanup/unregister on vsock_loopback_exit() - vsock_loopback: use virtio_vsock_skb_net()
Changes in v5: - add callbacks code to avoid reverse dependency - add logic for handling vsock_loopback setup for already existing namespaces --- include/net/af_vsock.h | 1 + include/net/netns/vsock.h | 6 +++ net/vmw_vsock/vsock_loopback.c | 98 ++++++++++++++++++++++++++++++++++++++---- 3 files changed, 97 insertions(+), 8 deletions(-)
diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h index 628e35ae9d00..5180b7dbb6d6 100644 --- a/include/net/af_vsock.h +++ b/include/net/af_vsock.h @@ -320,4 +320,5 @@ static inline bool vsock_net_check_mode(struct vsock_sock *vsk, struct net *net,
return orig_net_mode == VSOCK_NET_MODE_GLOBAL && vsk->orig_net_mode == VSOCK_NET_MODE_GLOBAL; } + #endif /* __AF_VSOCK_H__ */ diff --git a/include/net/netns/vsock.h b/include/net/netns/vsock.h index d4593c0b8dc4..a32d546793a2 100644 --- a/include/net/netns/vsock.h +++ b/include/net/netns/vsock.h @@ -9,6 +9,8 @@ enum vsock_net_mode { VSOCK_NET_MODE_LOCAL, };
+struct vsock_loopback; + struct netns_vsock { struct ctl_table_header *vsock_hdr; spinlock_t lock; @@ -16,5 +18,9 @@ struct netns_vsock { /* protected by lock */ enum vsock_net_mode mode; bool written; + +#if IS_ENABLED(CONFIG_VSOCKETS_LOOPBACK) + struct vsock_loopback *loopback; +#endif }; #endif /* __NET_NET_NAMESPACE_VSOCK_H */ diff --git a/net/vmw_vsock/vsock_loopback.c b/net/vmw_vsock/vsock_loopback.c index 1b2fab73e0d0..134e0619de07 100644 --- a/net/vmw_vsock/vsock_loopback.c +++ b/net/vmw_vsock/vsock_loopback.c @@ -28,8 +28,16 @@ static u32 vsock_loopback_get_local_cid(void)
static int vsock_loopback_send_pkt(struct sk_buff *skb) { - struct vsock_loopback *vsock = &the_vsock_loopback; + struct vsock_loopback *vsock; int len = skb->len; + struct net *net; + + net = virtio_vsock_skb_net(skb); + + if (net && net->vsock.mode == VSOCK_NET_MODE_LOCAL) + vsock = net->vsock.loopback; + else + vsock = &the_vsock_loopback;
virtio_vsock_skb_queue_tail(&vsock->pkt_queue, skb); queue_work(vsock->workqueue, &vsock->pkt_work); @@ -134,27 +142,99 @@ static void vsock_loopback_work(struct work_struct *work) } }
-static int __init vsock_loopback_init(void) +static int vsock_loopback_init_vsock(struct vsock_loopback *vsock) { - 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); + return 0; +} + +static void vsock_loopback_deinit_vsock(struct vsock_loopback *vsock) +{ + if (vsock->workqueue) + destroy_workqueue(vsock->workqueue); +} + +static int vsock_loopback_init_net(struct net *net) +{ + if (WARN_ON_ONCE(net->vsock.loopback)) + return 0; + + net->vsock.loopback = kmalloc(sizeof(*net->vsock.loopback), GFP_KERNEL); + if (!net->vsock.loopback) + return -ENOMEM; + + return vsock_loopback_init_vsock(net->vsock.loopback); +} + +static void vsock_loopback_exit_net(struct net *net) +{ + if (net->vsock.loopback) { + vsock_loopback_deinit_vsock(net->vsock.loopback); + kfree(net->vsock.loopback); + net->vsock.loopback = NULL; + } +} + +static void vsock_loopback_deinit_all(void) +{ + struct net *net; + + down_read(&net_rwsem); + for_each_net(net) + vsock_loopback_exit_net(net); + up_read(&net_rwsem); +} + +static struct pernet_operations vsock_loopback_net_ops = { + .init = vsock_loopback_init_net, + .exit = vsock_loopback_exit_net, +}; + +static int __init vsock_loopback_init(void) +{ + struct vsock_loopback *vsock = &the_vsock_loopback; + struct net *net; + int ret; + + ret = vsock_loopback_init_vsock(vsock); + if (ret < 0) + return ret; + + ret = register_pernet_subsys(&vsock_loopback_net_ops); + if (ret < 0) + goto out_deinit_vsock; + + /* call callbacks on any net previously created */ + down_read(&net_rwsem); + for_each_net(net) { + ret = vsock_loopback_init_net(net); + if (ret < 0) + break; + } + up_read(&net_rwsem); + + /* undo any initializations that succeeded */ + if (ret < 0) + goto out_deinit_pernet_vsock;
ret = vsock_core_register(&loopback_transport.transport, VSOCK_TRANSPORT_F_LOCAL); if (ret) - goto out_wq; + goto out_deinit_pernet_vsock; +
return 0;
-out_wq: - destroy_workqueue(vsock->workqueue); +out_deinit_pernet_vsock: + vsock_loopback_deinit_all(); + unregister_pernet_subsys(&vsock_loopback_net_ops); +out_deinit_vsock: + vsock_loopback_deinit_vsock(vsock); return ret; }
@@ -164,6 +244,8 @@ static void __exit vsock_loopback_exit(void)
vsock_core_unregister(&loopback_transport.transport);
+ vsock_loopback_deinit_all(); + flush_work(&vsock->pkt_work);
virtio_vsock_skb_queue_purge(&vsock->pkt_queue);