> From: Stefano Garzarella [mailto:sgarzare@xxxxxxxxxx] > Sent: Tuesday, November 19, 2019 12:01 PM > To: netdev@xxxxxxxxxxxxxxx > > This patch allows to register a transport able to handle > local communication (loopback). > > Signed-off-by: Stefano Garzarella <sgarzare@xxxxxxxxxx> > --- > include/net/af_vsock.h | 2 ++ > net/vmw_vsock/af_vsock.c | 17 ++++++++++++++++- > 2 files changed, 18 insertions(+), 1 deletion(-) > > diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h > index 4206dc6d813f..b1c717286993 100644 > --- a/include/net/af_vsock.h > +++ b/include/net/af_vsock.h > @@ -98,6 +98,8 @@ struct vsock_transport_send_notify_data { > #define VSOCK_TRANSPORT_F_G2H 0x00000002 > /* Transport provides DGRAM communication */ > #define VSOCK_TRANSPORT_F_DGRAM 0x00000004 > +/* Transport provides local (loopback) communication */ > +#define VSOCK_TRANSPORT_F_LOCAL 0x00000008 > > struct vsock_transport { > struct module *module; > diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c > index cc8659838bf2..c9e5bad59dc1 100644 > --- a/net/vmw_vsock/af_vsock.c > +++ b/net/vmw_vsock/af_vsock.c > @@ -136,6 +136,8 @@ static const struct vsock_transport *transport_h2g; > static const struct vsock_transport *transport_g2h; > /* Transport used for DGRAM communication */ > static const struct vsock_transport *transport_dgram; > +/* Transport used for local communication */ > +static const struct vsock_transport *transport_local; > static DEFINE_MUTEX(vsock_register_mutex); > > /**** UTILS ****/ > @@ -2130,7 +2132,7 @@ EXPORT_SYMBOL_GPL(vsock_core_get_transport); > > int vsock_core_register(const struct vsock_transport *t, int features) > { > - const struct vsock_transport *t_h2g, *t_g2h, *t_dgram; > + const struct vsock_transport *t_h2g, *t_g2h, *t_dgram, *t_local; > int err = mutex_lock_interruptible(&vsock_register_mutex); > > if (err) > @@ -2139,6 +2141,7 @@ int vsock_core_register(const struct > vsock_transport *t, int features) > t_h2g = transport_h2g; > t_g2h = transport_g2h; > t_dgram = transport_dgram; > + t_local = transport_local; > > if (features & VSOCK_TRANSPORT_F_H2G) { > if (t_h2g) { > @@ -2164,9 +2167,18 @@ int vsock_core_register(const struct > vsock_transport *t, int features) > t_dgram = t; > } > > + if (features & VSOCK_TRANSPORT_F_LOCAL) { > + if (t_local) { > + err = -EBUSY; > + goto err_busy; > + } > + t_local = t; > + } > + > transport_h2g = t_h2g; > transport_g2h = t_g2h; > transport_dgram = t_dgram; > + transport_local = t_local; > > err_busy: > mutex_unlock(&vsock_register_mutex); > @@ -2187,6 +2199,9 @@ void vsock_core_unregister(const struct > vsock_transport *t) > if (transport_dgram == t) > transport_dgram = NULL; > > + if (transport_local == t) > + transport_local = NULL; > + > mutex_unlock(&vsock_register_mutex); > } > EXPORT_SYMBOL_GPL(vsock_core_unregister); > -- > 2.21.0 Having loopback support as a separate transport fits nicely, but do we need to support different variants of loopback? It could just be built in. Thanks, Jorgen
