[net-next,04/14] vsock: add 'transport' member in the struct vsock_sock
diff mbox series

Message ID 20191023095554.11340-5-sgarzare@redhat.com
State Changes Requested
Delegated to: David Miller
Headers show
Series
  • vsock: add multi-transports support
Related show

Commit Message

Stefano Garzarella Oct. 23, 2019, 9:55 a.m. UTC
As a preparation to support multiple transports, this patch adds
the 'transport' member at the 'struct vsock_sock'.
This new field is initialized during the creation in the
__vsock_create() function.

This patch also renames the global 'transport' pointer to
'transport_single', since for now we're only supporting a single
transport registered at run-time.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
---
 include/net/af_vsock.h   |  1 +
 net/vmw_vsock/af_vsock.c | 56 +++++++++++++++++++++++++++-------------
 2 files changed, 39 insertions(+), 18 deletions(-)

Comments

Jorgen Hansen Oct. 30, 2019, 2:57 p.m. UTC | #1
> From: Stefano Garzarella [mailto:sgarzare@redhat.com]
> Sent: Wednesday, October 23, 2019 11:56 AM
> Subject: [PATCH net-next 04/14] vsock: add 'transport' member in the struct
> vsock_sock
> 
> As a preparation to support multiple transports, this patch adds the
> 'transport' member at the 'struct vsock_sock'.
> This new field is initialized during the creation in the
> __vsock_create() function.
> 
> This patch also renames the global 'transport' pointer to 'transport_single',
> since for now we're only supporting a single transport registered at run-time.
> 
> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
> Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
> ---
>  include/net/af_vsock.h   |  1 +
>  net/vmw_vsock/af_vsock.c | 56 +++++++++++++++++++++++++++----------
> ---
>  2 files changed, 39 insertions(+), 18 deletions(-)
> 
> diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h index
> c660402b10f2..a5e1e134261d 100644
> --- a/include/net/af_vsock.h
> +++ b/include/net/af_vsock.h
> @@ -27,6 +27,7 @@ extern spinlock_t vsock_table_lock;  struct vsock_sock {
>  	/* sk must be the first member. */
>  	struct sock sk;
> +	const struct vsock_transport *transport;
>  	struct sockaddr_vm local_addr;
>  	struct sockaddr_vm remote_addr;
>  	/* Links for the global tables of bound and connected sockets. */ diff
> --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c index
> 2f2582fb7fdd..c3a14f853eb0 100644
> --- a/net/vmw_vsock/af_vsock.c
> +++ b/net/vmw_vsock/af_vsock.c
> @@ -126,7 +126,7 @@ static struct proto vsock_proto = {
>   */
>  #define VSOCK_DEFAULT_CONNECT_TIMEOUT (2 * HZ)
> 
> -static const struct vsock_transport *transport;
> +static const struct vsock_transport *transport_single;
>  static DEFINE_MUTEX(vsock_register_mutex);
> 
>  /**** UTILS ****/
> @@ -408,7 +408,9 @@ static bool vsock_is_pending(struct sock *sk)
> 
>  static int vsock_send_shutdown(struct sock *sk, int mode)  {
> -	return transport->shutdown(vsock_sk(sk), mode);
> +	struct vsock_sock *vsk = vsock_sk(sk);
> +
> +	return vsk->transport->shutdown(vsk, mode);
>  }
> 
>  static void vsock_pending_work(struct work_struct *work) @@ -518,7
> +520,7 @@ static int __vsock_bind_stream(struct vsock_sock *vsk,  static int
> __vsock_bind_dgram(struct vsock_sock *vsk,
>  			      struct sockaddr_vm *addr)
>  {
> -	return transport->dgram_bind(vsk, addr);
> +	return vsk->transport->dgram_bind(vsk, addr);
>  }
> 
>  static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr) @@ -
> 536,7 +538,7 @@ static int __vsock_bind(struct sock *sk, struct sockaddr_vm
> *addr)
>  	 * like AF_INET prevents binding to a non-local IP address (in most
>  	 * cases), we only allow binding to the local CID.
>  	 */
> -	cid = transport->get_local_cid();
> +	cid = vsk->transport->get_local_cid();
>  	if (addr->svm_cid != cid && addr->svm_cid != VMADDR_CID_ANY)
>  		return -EADDRNOTAVAIL;
> 
> @@ -586,6 +588,7 @@ struct sock *__vsock_create(struct net *net,
>  		sk->sk_type = type;
> 
>  	vsk = vsock_sk(sk);
> +	vsk->transport = transport_single;
>  	vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY,
> VMADDR_PORT_ANY);
>  	vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY,
> VMADDR_PORT_ANY);
> 
> @@ -616,7 +619,7 @@ struct sock *__vsock_create(struct net *net,
>  		vsk->connect_timeout =
> VSOCK_DEFAULT_CONNECT_TIMEOUT;
>  	}
> 
> -	if (transport->init(vsk, psk) < 0) {
> +	if (vsk->transport->init(vsk, psk) < 0) {
>  		sk_free(sk);
>  		return NULL;
>  	}
> @@ -641,7 +644,7 @@ static void __vsock_release(struct sock *sk, int level)
>  		/* The release call is supposed to use lock_sock_nested()
>  		 * rather than lock_sock(), if a sock lock should be acquired.
>  		 */
> -		transport->release(vsk);
> +		vsk->transport->release(vsk);
> 
>  		/* When "level" is SINGLE_DEPTH_NESTING, use the nested
>  		 * version to avoid the warning "possible recursive locking
> @@ -670,7 +673,7 @@ static void vsock_sk_destruct(struct sock *sk)  {
>  	struct vsock_sock *vsk = vsock_sk(sk);
> 
> -	transport->destruct(vsk);
> +	vsk->transport->destruct(vsk);
> 
>  	/* When clearing these addresses, there's no need to set the family
> and
>  	 * possibly register the address family with the kernel.
> @@ -694,13 +697,13 @@ static int vsock_queue_rcv_skb(struct sock *sk,
> struct sk_buff *skb)
> 
>  s64 vsock_stream_has_data(struct vsock_sock *vsk)  {
> -	return transport->stream_has_data(vsk);
> +	return vsk->transport->stream_has_data(vsk);
>  }
>  EXPORT_SYMBOL_GPL(vsock_stream_has_data);
> 
>  s64 vsock_stream_has_space(struct vsock_sock *vsk)  {
> -	return transport->stream_has_space(vsk);
> +	return vsk->transport->stream_has_space(vsk);
>  }
>  EXPORT_SYMBOL_GPL(vsock_stream_has_space);
> 
> @@ -869,6 +872,7 @@ static __poll_t vsock_poll(struct file *file, struct
> socket *sock,
>  			mask |= EPOLLOUT | EPOLLWRNORM |
> EPOLLWRBAND;
> 
>  	} else if (sock->type == SOCK_STREAM) {
> +		const struct vsock_transport *transport = vsk->transport;
>  		lock_sock(sk);
> 
>  		/* Listening sockets that have connections in their accept
> @@ -944,6 +948,7 @@ static int vsock_dgram_sendmsg(struct socket *sock,
> struct msghdr *msg,
>  	struct sock *sk;
>  	struct vsock_sock *vsk;
>  	struct sockaddr_vm *remote_addr;
> +	const struct vsock_transport *transport;
> 
>  	if (msg->msg_flags & MSG_OOB)
>  		return -EOPNOTSUPP;
> @@ -952,6 +957,7 @@ static int vsock_dgram_sendmsg(struct socket *sock,
> struct msghdr *msg,
>  	err = 0;
>  	sk = sock->sk;
>  	vsk = vsock_sk(sk);
> +	transport = vsk->transport;
> 
>  	lock_sock(sk);
> 
> @@ -1036,8 +1042,8 @@ static int vsock_dgram_connect(struct socket
> *sock,
>  	if (err)
>  		goto out;
> 
> -	if (!transport->dgram_allow(remote_addr->svm_cid,
> -				    remote_addr->svm_port)) {
> +	if (!vsk->transport->dgram_allow(remote_addr->svm_cid,
> +					 remote_addr->svm_port)) {
>  		err = -EINVAL;
>  		goto out;
>  	}
> @@ -1053,7 +1059,9 @@ static int vsock_dgram_connect(struct socket
> *sock,  static int vsock_dgram_recvmsg(struct socket *sock, struct msghdr
> *msg,
>  			       size_t len, int flags)
>  {
> -	return transport->dgram_dequeue(vsock_sk(sock->sk), msg, len,
> flags);
> +	struct vsock_sock *vsk = vsock_sk(sock->sk);
> +
> +	return vsk->transport->dgram_dequeue(vsk, msg, len, flags);
>  }
> 
>  static const struct proto_ops vsock_dgram_ops = { @@ -1079,6 +1087,8 @@
> static const struct proto_ops vsock_dgram_ops = {
> 
>  static int vsock_transport_cancel_pkt(struct vsock_sock *vsk)  {
> +	const struct vsock_transport *transport = vsk->transport;
> +
>  	if (!transport->cancel_pkt)
>  		return -EOPNOTSUPP;
> 
> @@ -1115,6 +1125,7 @@ static int vsock_stream_connect(struct socket
> *sock, struct sockaddr *addr,
>  	int err;
>  	struct sock *sk;
>  	struct vsock_sock *vsk;
> +	const struct vsock_transport *transport;
>  	struct sockaddr_vm *remote_addr;
>  	long timeout;
>  	DEFINE_WAIT(wait);
> @@ -1122,6 +1133,7 @@ static int vsock_stream_connect(struct socket
> *sock, struct sockaddr *addr,
>  	err = 0;
>  	sk = sock->sk;
>  	vsk = vsock_sk(sk);
> +	transport = vsk->transport;
> 
>  	lock_sock(sk);
> 
> @@ -1365,6 +1377,7 @@ static int vsock_stream_setsockopt(struct socket
> *sock,
>  	int err;
>  	struct sock *sk;
>  	struct vsock_sock *vsk;
> +	const struct vsock_transport *transport;
>  	u64 val;
> 
>  	if (level != AF_VSOCK)
> @@ -1385,6 +1398,7 @@ static int vsock_stream_setsockopt(struct socket
> *sock,
>  	err = 0;
>  	sk = sock->sk;
>  	vsk = vsock_sk(sk);
> +	transport = vsk->transport;
> 
>  	lock_sock(sk);
> 
> @@ -1442,6 +1456,7 @@ static int vsock_stream_getsockopt(struct socket
> *sock,
>  	int len;
>  	struct sock *sk;
>  	struct vsock_sock *vsk;
> +	const struct vsock_transport *transport;
>  	u64 val;
> 
>  	if (level != AF_VSOCK)
> @@ -1465,6 +1480,7 @@ static int vsock_stream_getsockopt(struct socket
> *sock,
>  	err = 0;
>  	sk = sock->sk;
>  	vsk = vsock_sk(sk);
> +	transport = vsk->transport;
> 
>  	switch (optname) {
>  	case SO_VM_SOCKETS_BUFFER_SIZE:
> @@ -1509,6 +1525,7 @@ static int vsock_stream_sendmsg(struct socket
> *sock, struct msghdr *msg,  {
>  	struct sock *sk;
>  	struct vsock_sock *vsk;
> +	const struct vsock_transport *transport;
>  	ssize_t total_written;
>  	long timeout;
>  	int err;
> @@ -1517,6 +1534,7 @@ static int vsock_stream_sendmsg(struct socket
> *sock, struct msghdr *msg,
> 
>  	sk = sock->sk;
>  	vsk = vsock_sk(sk);
> +	transport = vsk->transport;
>  	total_written = 0;
>  	err = 0;
> 
> @@ -1648,6 +1666,7 @@ vsock_stream_recvmsg(struct socket *sock, struct
> msghdr *msg, size_t len,  {
>  	struct sock *sk;
>  	struct vsock_sock *vsk;
> +	const struct vsock_transport *transport;
>  	int err;
>  	size_t target;
>  	ssize_t copied;
> @@ -1658,6 +1677,7 @@ vsock_stream_recvmsg(struct socket *sock, struct
> msghdr *msg, size_t len,
> 
>  	sk = sock->sk;
>  	vsk = vsock_sk(sk);
> +	transport = vsk->transport;
>  	err = 0;
> 
>  	lock_sock(sk);
> @@ -1872,7 +1892,7 @@ static long vsock_dev_do_ioctl(struct file *filp,
> 
>  	switch (cmd) {
>  	case IOCTL_VM_SOCKETS_GET_LOCAL_CID:
> -		if (put_user(transport->get_local_cid(), p) != 0)
> +		if (put_user(transport_single->get_local_cid(), p) != 0)
>  			retval = -EFAULT;
>  		break;
> 
> @@ -1919,7 +1939,7 @@ int __vsock_core_init(const struct vsock_transport
> *t, struct module *owner)
>  	if (err)
>  		return err;
> 
> -	if (transport) {
> +	if (transport_single) {
>  		err = -EBUSY;
>  		goto err_busy;
>  	}
> @@ -1928,7 +1948,7 @@ int __vsock_core_init(const struct vsock_transport
> *t, struct module *owner)
>  	 * unload while there are open sockets.
>  	 */
>  	vsock_proto.owner = owner;
> -	transport = t;
> +	transport_single = t;
> 
>  	vsock_device.minor = MISC_DYNAMIC_MINOR;
>  	err = misc_register(&vsock_device);
> @@ -1958,7 +1978,7 @@ int __vsock_core_init(const struct vsock_transport
> *t, struct module *owner)
>  err_deregister_misc:
>  	misc_deregister(&vsock_device);
>  err_reset_transport:
> -	transport = NULL;
> +	transport_single = NULL;
>  err_busy:
>  	mutex_unlock(&vsock_register_mutex);
>  	return err;
> @@ -1975,7 +1995,7 @@ void vsock_core_exit(void)
> 
>  	/* We do not want the assignment below re-ordered. */
>  	mb();
> -	transport = NULL;
> +	transport_single = NULL;
> 
>  	mutex_unlock(&vsock_register_mutex);
>  }
> @@ -1986,7 +2006,7 @@ const struct vsock_transport
> *vsock_core_get_transport(void)
>  	/* vsock_register_mutex not taken since only the transport uses this
>  	 * function and only while registered.
>  	 */
> -	return transport;
> +	return transport_single;
>  }
>  EXPORT_SYMBOL_GPL(vsock_core_get_transport);
> 
> --
> 2.21.0

Reviewed-by: Jorgen Hansen <jhansen@vmware.com>

Patch
diff mbox series

diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h
index c660402b10f2..a5e1e134261d 100644
--- a/include/net/af_vsock.h
+++ b/include/net/af_vsock.h
@@ -27,6 +27,7 @@  extern spinlock_t vsock_table_lock;
 struct vsock_sock {
 	/* sk must be the first member. */
 	struct sock sk;
+	const struct vsock_transport *transport;
 	struct sockaddr_vm local_addr;
 	struct sockaddr_vm remote_addr;
 	/* Links for the global tables of bound and connected sockets. */
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 2f2582fb7fdd..c3a14f853eb0 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -126,7 +126,7 @@  static struct proto vsock_proto = {
  */
 #define VSOCK_DEFAULT_CONNECT_TIMEOUT (2 * HZ)
 
-static const struct vsock_transport *transport;
+static const struct vsock_transport *transport_single;
 static DEFINE_MUTEX(vsock_register_mutex);
 
 /**** UTILS ****/
@@ -408,7 +408,9 @@  static bool vsock_is_pending(struct sock *sk)
 
 static int vsock_send_shutdown(struct sock *sk, int mode)
 {
-	return transport->shutdown(vsock_sk(sk), mode);
+	struct vsock_sock *vsk = vsock_sk(sk);
+
+	return vsk->transport->shutdown(vsk, mode);
 }
 
 static void vsock_pending_work(struct work_struct *work)
@@ -518,7 +520,7 @@  static int __vsock_bind_stream(struct vsock_sock *vsk,
 static int __vsock_bind_dgram(struct vsock_sock *vsk,
 			      struct sockaddr_vm *addr)
 {
-	return transport->dgram_bind(vsk, addr);
+	return vsk->transport->dgram_bind(vsk, addr);
 }
 
 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr)
@@ -536,7 +538,7 @@  static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr)
 	 * like AF_INET prevents binding to a non-local IP address (in most
 	 * cases), we only allow binding to the local CID.
 	 */
-	cid = transport->get_local_cid();
+	cid = vsk->transport->get_local_cid();
 	if (addr->svm_cid != cid && addr->svm_cid != VMADDR_CID_ANY)
 		return -EADDRNOTAVAIL;
 
@@ -586,6 +588,7 @@  struct sock *__vsock_create(struct net *net,
 		sk->sk_type = type;
 
 	vsk = vsock_sk(sk);
+	vsk->transport = transport_single;
 	vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 	vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 
@@ -616,7 +619,7 @@  struct sock *__vsock_create(struct net *net,
 		vsk->connect_timeout = VSOCK_DEFAULT_CONNECT_TIMEOUT;
 	}
 
-	if (transport->init(vsk, psk) < 0) {
+	if (vsk->transport->init(vsk, psk) < 0) {
 		sk_free(sk);
 		return NULL;
 	}
@@ -641,7 +644,7 @@  static void __vsock_release(struct sock *sk, int level)
 		/* The release call is supposed to use lock_sock_nested()
 		 * rather than lock_sock(), if a sock lock should be acquired.
 		 */
-		transport->release(vsk);
+		vsk->transport->release(vsk);
 
 		/* When "level" is SINGLE_DEPTH_NESTING, use the nested
 		 * version to avoid the warning "possible recursive locking
@@ -670,7 +673,7 @@  static void vsock_sk_destruct(struct sock *sk)
 {
 	struct vsock_sock *vsk = vsock_sk(sk);
 
-	transport->destruct(vsk);
+	vsk->transport->destruct(vsk);
 
 	/* When clearing these addresses, there's no need to set the family and
 	 * possibly register the address family with the kernel.
@@ -694,13 +697,13 @@  static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 
 s64 vsock_stream_has_data(struct vsock_sock *vsk)
 {
-	return transport->stream_has_data(vsk);
+	return vsk->transport->stream_has_data(vsk);
 }
 EXPORT_SYMBOL_GPL(vsock_stream_has_data);
 
 s64 vsock_stream_has_space(struct vsock_sock *vsk)
 {
-	return transport->stream_has_space(vsk);
+	return vsk->transport->stream_has_space(vsk);
 }
 EXPORT_SYMBOL_GPL(vsock_stream_has_space);
 
@@ -869,6 +872,7 @@  static __poll_t vsock_poll(struct file *file, struct socket *sock,
 			mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
 
 	} else if (sock->type == SOCK_STREAM) {
+		const struct vsock_transport *transport = vsk->transport;
 		lock_sock(sk);
 
 		/* Listening sockets that have connections in their accept
@@ -944,6 +948,7 @@  static int vsock_dgram_sendmsg(struct socket *sock, struct msghdr *msg,
 	struct sock *sk;
 	struct vsock_sock *vsk;
 	struct sockaddr_vm *remote_addr;
+	const struct vsock_transport *transport;
 
 	if (msg->msg_flags & MSG_OOB)
 		return -EOPNOTSUPP;
@@ -952,6 +957,7 @@  static int vsock_dgram_sendmsg(struct socket *sock, struct msghdr *msg,
 	err = 0;
 	sk = sock->sk;
 	vsk = vsock_sk(sk);
+	transport = vsk->transport;
 
 	lock_sock(sk);
 
@@ -1036,8 +1042,8 @@  static int vsock_dgram_connect(struct socket *sock,
 	if (err)
 		goto out;
 
-	if (!transport->dgram_allow(remote_addr->svm_cid,
-				    remote_addr->svm_port)) {
+	if (!vsk->transport->dgram_allow(remote_addr->svm_cid,
+					 remote_addr->svm_port)) {
 		err = -EINVAL;
 		goto out;
 	}
@@ -1053,7 +1059,9 @@  static int vsock_dgram_connect(struct socket *sock,
 static int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg,
 			       size_t len, int flags)
 {
-	return transport->dgram_dequeue(vsock_sk(sock->sk), msg, len, flags);
+	struct vsock_sock *vsk = vsock_sk(sock->sk);
+
+	return vsk->transport->dgram_dequeue(vsk, msg, len, flags);
 }
 
 static const struct proto_ops vsock_dgram_ops = {
@@ -1079,6 +1087,8 @@  static const struct proto_ops vsock_dgram_ops = {
 
 static int vsock_transport_cancel_pkt(struct vsock_sock *vsk)
 {
+	const struct vsock_transport *transport = vsk->transport;
+
 	if (!transport->cancel_pkt)
 		return -EOPNOTSUPP;
 
@@ -1115,6 +1125,7 @@  static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
 	int err;
 	struct sock *sk;
 	struct vsock_sock *vsk;
+	const struct vsock_transport *transport;
 	struct sockaddr_vm *remote_addr;
 	long timeout;
 	DEFINE_WAIT(wait);
@@ -1122,6 +1133,7 @@  static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
 	err = 0;
 	sk = sock->sk;
 	vsk = vsock_sk(sk);
+	transport = vsk->transport;
 
 	lock_sock(sk);
 
@@ -1365,6 +1377,7 @@  static int vsock_stream_setsockopt(struct socket *sock,
 	int err;
 	struct sock *sk;
 	struct vsock_sock *vsk;
+	const struct vsock_transport *transport;
 	u64 val;
 
 	if (level != AF_VSOCK)
@@ -1385,6 +1398,7 @@  static int vsock_stream_setsockopt(struct socket *sock,
 	err = 0;
 	sk = sock->sk;
 	vsk = vsock_sk(sk);
+	transport = vsk->transport;
 
 	lock_sock(sk);
 
@@ -1442,6 +1456,7 @@  static int vsock_stream_getsockopt(struct socket *sock,
 	int len;
 	struct sock *sk;
 	struct vsock_sock *vsk;
+	const struct vsock_transport *transport;
 	u64 val;
 
 	if (level != AF_VSOCK)
@@ -1465,6 +1480,7 @@  static int vsock_stream_getsockopt(struct socket *sock,
 	err = 0;
 	sk = sock->sk;
 	vsk = vsock_sk(sk);
+	transport = vsk->transport;
 
 	switch (optname) {
 	case SO_VM_SOCKETS_BUFFER_SIZE:
@@ -1509,6 +1525,7 @@  static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg,
 {
 	struct sock *sk;
 	struct vsock_sock *vsk;
+	const struct vsock_transport *transport;
 	ssize_t total_written;
 	long timeout;
 	int err;
@@ -1517,6 +1534,7 @@  static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg,
 
 	sk = sock->sk;
 	vsk = vsock_sk(sk);
+	transport = vsk->transport;
 	total_written = 0;
 	err = 0;
 
@@ -1648,6 +1666,7 @@  vsock_stream_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
 {
 	struct sock *sk;
 	struct vsock_sock *vsk;
+	const struct vsock_transport *transport;
 	int err;
 	size_t target;
 	ssize_t copied;
@@ -1658,6 +1677,7 @@  vsock_stream_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
 
 	sk = sock->sk;
 	vsk = vsock_sk(sk);
+	transport = vsk->transport;
 	err = 0;
 
 	lock_sock(sk);
@@ -1872,7 +1892,7 @@  static long vsock_dev_do_ioctl(struct file *filp,
 
 	switch (cmd) {
 	case IOCTL_VM_SOCKETS_GET_LOCAL_CID:
-		if (put_user(transport->get_local_cid(), p) != 0)
+		if (put_user(transport_single->get_local_cid(), p) != 0)
 			retval = -EFAULT;
 		break;
 
@@ -1919,7 +1939,7 @@  int __vsock_core_init(const struct vsock_transport *t, struct module *owner)
 	if (err)
 		return err;
 
-	if (transport) {
+	if (transport_single) {
 		err = -EBUSY;
 		goto err_busy;
 	}
@@ -1928,7 +1948,7 @@  int __vsock_core_init(const struct vsock_transport *t, struct module *owner)
 	 * unload while there are open sockets.
 	 */
 	vsock_proto.owner = owner;
-	transport = t;
+	transport_single = t;
 
 	vsock_device.minor = MISC_DYNAMIC_MINOR;
 	err = misc_register(&vsock_device);
@@ -1958,7 +1978,7 @@  int __vsock_core_init(const struct vsock_transport *t, struct module *owner)
 err_deregister_misc:
 	misc_deregister(&vsock_device);
 err_reset_transport:
-	transport = NULL;
+	transport_single = NULL;
 err_busy:
 	mutex_unlock(&vsock_register_mutex);
 	return err;
@@ -1975,7 +1995,7 @@  void vsock_core_exit(void)
 
 	/* We do not want the assignment below re-ordered. */
 	mb();
-	transport = NULL;
+	transport_single = NULL;
 
 	mutex_unlock(&vsock_register_mutex);
 }
@@ -1986,7 +2006,7 @@  const struct vsock_transport *vsock_core_get_transport(void)
 	/* vsock_register_mutex not taken since only the transport uses this
 	 * function and only while registered.
 	 */
-	return transport;
+	return transport_single;
 }
 EXPORT_SYMBOL_GPL(vsock_core_get_transport);