[PATCH RFC net-next v4 02/11] vsock: a per-net vsock NS mode state

[Bobby Eshleman <bobbyeshleman@gmail.com>]

From: Bobby Eshleman <bobbyeshleman@meta.com>

Add the per-net vsock NS mode state. This only adds the structure for
holding the mode necessary and some of the definitions, but does not
integrate the functionality yet.

Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
---
 MAINTAINERS                 |  1 +
 include/net/net_namespace.h |  4 ++++
 include/net/netns/vsock.h   | 19 +++++++++++++++++++
 3 files changed, 24 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 507c5ff6f620..bf9015498854 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -26149,6 +26149,7 @@ L:	netdev@vger.kernel.org
 S:	Maintained
 F:	drivers/vhost/vsock.c
 F:	include/linux/virtio_vsock.h
+F:	include/net/netns/vsock.h
 F:	include/uapi/linux/virtio_vsock.h
 F:	net/vmw_vsock/virtio_transport.c
 F:	net/vmw_vsock/virtio_transport_common.c
diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h
index 025a7574b275..005c0da4fb62 100644
--- a/include/net/net_namespace.h
+++ b/include/net/net_namespace.h
@@ -37,6 +37,7 @@
 #include <net/netns/smc.h>
 #include <net/netns/bpf.h>
 #include <net/netns/mctp.h>
+#include <net/netns/vsock.h>
 #include <net/net_trackers.h>
 #include <linux/ns_common.h>
 #include <linux/idr.h>
@@ -196,6 +197,9 @@ struct net {
 	/* Move to a better place when the config guard is removed. */
 	struct mutex		rtnl_mutex;
 #endif
+#if IS_ENABLED(CONFIG_VSOCKETS)
+	struct netns_vsock	vsock;
+#endif
 } __randomize_layout;
 
 #include <linux/seq_file_net.h>
diff --git a/include/net/netns/vsock.h b/include/net/netns/vsock.h
new file mode 100644
index 000000000000..ea14b46ed437
--- /dev/null
+++ b/include/net/netns/vsock.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __NET_NET_NAMESPACE_VSOCK_H
+#define __NET_NET_NAMESPACE_VSOCK_H
+
+#include <linux/types.h>
+
+// TODO: rename to VSOCK_NET_* ?
+#define VSOCK_NS_MODE_GLOBAL	1
+#define VSOCK_NS_MODE_LOCAL	(1 << 1)
+#define VSOCK_NS_MODE_INVALID	(~0)
+/* VSOCK_NS_MODE_WRITTEN_ONCE indicates "write-once" write has occurred */
+#define VSOCK_NS_MODE_WRITTEN_ONCE	(1 << 7)
+
+struct netns_vsock {
+	struct ctl_table_header *vsock_hdr;
+	spinlock_t lock;
+	u8 ns_mode;
+};
+#endif /* __NET_NET_NAMESPACE_VSOCK_H */

-- 
2.47.1