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 v7: - drop for_each_net() init/exit, drop net_rwsem, the pernet registration handles this automatically and race-free - flush workqueue before destruction, purge pkt list - remember net_mode instead of current net mode - keep space after INIT_WORK() - change vsock_loopback in netns_vsock to ->priv void ptr - rename `orig_net_mode` to `net_mode` - remove useless comment - protect `register_pernet_subsys()` with `net_rwsem` - do cleanup before releasing `net_rwsem` when failure happens - call `unregister_pernet_subsys()` in `vsock_loopback_exit()` - call `vsock_loopback_deinit_vsock()` in `vsock_loopback_exit()`
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/netns/vsock.h | 2 + net/vmw_vsock/vsock_loopback.c | 85 ++++++++++++++++++++++++++++++++++++------ 2 files changed, 75 insertions(+), 12 deletions(-)
diff --git a/include/net/netns/vsock.h b/include/net/netns/vsock.h index c9a438ad52f2..9d0d8e2fbc37 100644 --- a/include/net/netns/vsock.h +++ b/include/net/netns/vsock.h @@ -16,5 +16,7 @@ struct netns_vsock { /* protected by lock */ enum vsock_net_mode mode; bool mode_locked; + + void *priv; }; #endif /* __NET_NET_NAMESPACE_VSOCK_H */ diff --git a/net/vmw_vsock/vsock_loopback.c b/net/vmw_vsock/vsock_loopback.c index a8f218f0c5a3..474083d4cfcb 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 (virtio_vsock_skb_net_mode(skb) == VSOCK_NET_MODE_LOCAL) + vsock = (struct vsock_loopback *)net->vsock.priv; + else + vsock = &the_vsock_loopback;
virtio_vsock_skb_queue_tail(&vsock->pkt_queue, skb); queue_work(vsock->workqueue, &vsock->pkt_work); @@ -134,11 +142,8 @@ 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", WQ_PERCPU, 0); if (!vsock->workqueue) return -ENOMEM; @@ -146,15 +151,73 @@ static int __init vsock_loopback_init(void) 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) { + flush_work(&vsock->pkt_work); + virtio_vsock_skb_queue_purge(&vsock->pkt_queue); + destroy_workqueue(vsock->workqueue); + vsock->workqueue = NULL; + } +} + +static int vsock_loopback_init_net(struct net *net) +{ + int ret; + + net->vsock.priv = kzalloc(sizeof(struct vsock_loopback), GFP_KERNEL); + if (!net->vsock.priv) + return -ENOMEM; + + ret = vsock_loopback_init_vsock((struct vsock_loopback *)net->vsock.priv); + if (ret < 0) { + kfree(net->vsock.priv); + net->vsock.priv = NULL; + return ret; + } + + return 0; +} + +static void vsock_loopback_exit_net(struct net *net) +{ + vsock_loopback_deinit_vsock(net->vsock.priv); + kfree(net->vsock.priv); + net->vsock.priv = NULL; +} + +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; + 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; + ret = vsock_core_register(&loopback_transport.transport, VSOCK_TRANSPORT_F_LOCAL); if (ret) - goto out_wq; + goto out_unregister_pernet_subsys;
return 0;
-out_wq: - destroy_workqueue(vsock->workqueue); +out_unregister_pernet_subsys: + unregister_pernet_subsys(&vsock_loopback_net_ops); +out_deinit_vsock: + vsock_loopback_deinit_vsock(vsock); return ret; }
@@ -164,11 +227,9 @@ static void __exit vsock_loopback_exit(void)
vsock_core_unregister(&loopback_transport.transport);
- flush_work(&vsock->pkt_work); - - virtio_vsock_skb_queue_purge(&vsock->pkt_queue); + unregister_pernet_subsys(&vsock_loopback_net_ops);
- destroy_workqueue(vsock->workqueue); + vsock_loopback_deinit_vsock(vsock); }
module_init(vsock_loopback_init);