From c0cfa2d8a788fcf45df5bf4070ab2474c88d543a Mon Sep 17 00:00:00 2001 From: Stefano Garzarella Date: Thu, 14 Nov 2019 10:57:46 +0100 Subject: vsock: add multi-transports support This patch adds the support of multiple transports in the VSOCK core. With the multi-transports support, we can use vsock with nested VMs (using also different hypervisors) loading both guest->host and host->guest transports at the same time. Major changes: - vsock core module can be loaded regardless of the transports - vsock_core_init() and vsock_core_exit() are renamed to vsock_core_register() and vsock_core_unregister() - vsock_core_register() has a feature parameter (H2G, G2H, DGRAM) to identify which directions the transport can handle and if it's support DGRAM (only vmci) - each stream socket is assigned to a transport when the remote CID is set (during the connect() or when we receive a connection request on a listener socket). The remote CID is used to decide which transport to use: - remote CID <= VMADDR_CID_HOST will use guest->host transport; - remote CID == local_cid (guest->host transport) will use guest->host transport for loopback (host->guest transports don't support loopback); - remote CID > VMADDR_CID_HOST will use host->guest transport; - listener sockets are not bound to any transports since no transport operations are done on it. In this way we can create a listener socket, also if the transports are not loaded or with VMADDR_CID_ANY to listen on all transports. - DGRAM sockets are handled as before, since only the vmci_transport provides this feature. Signed-off-by: Stefano Garzarella Signed-off-by: David S. Miller --- include/net/af_vsock.h | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) (limited to 'include/net') diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h index fa1570dc9f5c..cf5c3691251b 100644 --- a/include/net/af_vsock.h +++ b/include/net/af_vsock.h @@ -91,6 +91,14 @@ struct vsock_transport_send_notify_data { u64 data2; /* Transport-defined. */ }; +/* Transport features flags */ +/* Transport provides host->guest communication */ +#define VSOCK_TRANSPORT_F_H2G 0x00000001 +/* Transport provides guest->host communication */ +#define VSOCK_TRANSPORT_F_G2H 0x00000002 +/* Transport provides DGRAM communication */ +#define VSOCK_TRANSPORT_F_DGRAM 0x00000004 + struct vsock_transport { /* Initialize/tear-down socket. */ int (*init)(struct vsock_sock *, struct vsock_sock *); @@ -154,12 +162,8 @@ struct vsock_transport { /**** CORE ****/ -int __vsock_core_init(const struct vsock_transport *t, struct module *owner); -static inline int vsock_core_init(const struct vsock_transport *t) -{ - return __vsock_core_init(t, THIS_MODULE); -} -void vsock_core_exit(void); +int vsock_core_register(const struct vsock_transport *t, int features); +void vsock_core_unregister(const struct vsock_transport *t); /* The transport may downcast this to access transport-specific functions */ const struct vsock_transport *vsock_core_get_transport(struct vsock_sock *vsk); @@ -190,6 +194,8 @@ struct sock *vsock_find_connected_socket(struct sockaddr_vm *src, struct sockaddr_vm *dst); void vsock_remove_sock(struct vsock_sock *vsk); void vsock_for_each_connected_socket(void (*fn)(struct sock *sk)); +int vsock_assign_transport(struct vsock_sock *vsk, struct vsock_sock *psk); +bool vsock_find_cid(unsigned int cid); /**** TAP ****/ -- cgit