RE: [PATCH net-next 04/14] vsock: add 'transport' member in the struct vsock_sock

Jorgen Hansen
2019-10-30T14:58:00Z

> 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>