From: Bobby Eshleman <bobbyeshle...@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 <bobbyeshle...@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);
--
2.47.3
