On Wed, 30 Apr 2025 at 12:33, Michal Luczaj <m...@rbox.co> wrote:
>
> On 4/30/25 11:36, Stefano Garzarella wrote:
> > On Wed, Apr 30, 2025 at 11:10:29AM +0200, Michal Luczaj wrote:
> >> Lingering should be transport-independent in the long run. In preparation
> >> for supporting other transports, as well the linger on shutdown(), move
> >> code to core.
> >>
> >> Guard against an unimplemented vsock_transport::unsent_bytes() callback.
> >>
> >> Suggested-by: Stefano Garzarella <sgarz...@redhat.com>
> >> Signed-off-by: Michal Luczaj <m...@rbox.co>
> >> ---
> >> include/net/af_vsock.h | 1 +
> >> net/vmw_vsock/af_vsock.c | 25 +++++++++++++++++++++++++
> >> net/vmw_vsock/virtio_transport_common.c | 23 +----------------------
> >> 3 files changed, 27 insertions(+), 22 deletions(-)
> >>
> >> diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h
> >> index
> >> 9e85424c834353d016a527070dd62e15ff3bfce1..bd8b88d70423051dd05fc445fe37971af631ba03
> >> 100644
> >> --- a/include/net/af_vsock.h
> >> +++ b/include/net/af_vsock.h
> >> @@ -221,6 +221,7 @@ void vsock_for_each_connected_socket(struct
> >> vsock_transport *transport,
> >> void (*fn)(struct sock *sk));
> >> int vsock_assign_transport(struct vsock_sock *vsk, struct vsock_sock *psk);
> >> bool vsock_find_cid(unsigned int cid);
> >> +void vsock_linger(struct sock *sk, long timeout);
> >>
> >> /**** TAP ****/
> >>
> >> diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
> >> index
> >> fc6afbc8d6806a4d98c66abc3af4bd139c583b08..946b37de679a0e68b84cd982a3af2a959c60ee57
> >> 100644
> >> --- a/net/vmw_vsock/af_vsock.c
> >> +++ b/net/vmw_vsock/af_vsock.c
> >> @@ -1013,6 +1013,31 @@ static int vsock_getname(struct socket *sock,
> >> return err;
> >> }
> >>
> >> +void vsock_linger(struct sock *sk, long timeout)
> >> +{
> >> + DEFINE_WAIT_FUNC(wait, woken_wake_function);
> >> + ssize_t (*unsent)(struct vsock_sock *vsk);
> >> + struct vsock_sock *vsk = vsock_sk(sk);
> >> +
> >> + if (!timeout)
> >> + return;
> >> +
> >> + /* unsent_bytes() may be unimplemented. */
> >> + unsent = vsk->transport->unsent_bytes;
> >> + if (!unsent)
> >> + return;
> >> +
> >> + add_wait_queue(sk_sleep(sk), &wait);
> >> +
> >> + do {
> >> + if (sk_wait_event(sk, &timeout, unsent(vsk) == 0, &wait))
> >> + break;
> >> + } while (!signal_pending(current) && timeout);
> >> +
> >> + remove_wait_queue(sk_sleep(sk), &wait);
> >> +}
> >> +EXPORT_SYMBOL_GPL(vsock_linger);
> >> +
> >> static int vsock_shutdown(struct socket *sock, int mode)
> >> {
> >> int err;
> >> diff --git a/net/vmw_vsock/virtio_transport_common.c
> >> b/net/vmw_vsock/virtio_transport_common.c
> >> index
> >> 4425802c5d718f65aaea425ea35886ad64e2fe6e..9230b8358ef2ac1f6e72a5961bae39f9093c8884
> >> 100644
> >> --- a/net/vmw_vsock/virtio_transport_common.c
> >> +++ b/net/vmw_vsock/virtio_transport_common.c
> >> @@ -1192,27 +1192,6 @@ static void virtio_transport_remove_sock(struct
> >> vsock_sock *vsk)
> >> vsock_remove_sock(vsk);
> >> }
> >>
> >> -static void virtio_transport_wait_close(struct sock *sk, long timeout)
> >> -{
> >> - DEFINE_WAIT_FUNC(wait, woken_wake_function);
> >> - ssize_t (*unsent)(struct vsock_sock *vsk);
> >> - struct vsock_sock *vsk = vsock_sk(sk);
> >> -
> >> - if (!timeout)
> >> - return;
> >> -
> >> - unsent = vsk->transport->unsent_bytes;
> >> -
> >> - add_wait_queue(sk_sleep(sk), &wait);
> >> -
> >> - do {
> >> - if (sk_wait_event(sk, &timeout, unsent(vsk) == 0, &wait))
> >> - break;
> >> - } while (!signal_pending(current) && timeout);
> >> -
> >> - remove_wait_queue(sk_sleep(sk), &wait);
> >> -}
> >> -
> >> static void virtio_transport_cancel_close_work(struct vsock_sock *vsk,
> >> bool cancel_timeout)
> >> {
> >> @@ -1283,7 +1262,7 @@ static bool virtio_transport_close(struct vsock_sock
> >> *vsk)
> >> (void)virtio_transport_shutdown(vsk, SHUTDOWN_MASK);
> >>
> >> if (sock_flag(sk, SOCK_LINGER) && !(current->flags & PF_EXITING))
> >> - virtio_transport_wait_close(sk, sk->sk_lingertime);
> >> + vsock_linger(sk, sk->sk_lingertime);
> >
> > Ah, I'd also move the check in that function, I mean:
> >
> > void vsock_linger(struct sock *sk) {
> > ...
> > if (!sock_flag(sk, SOCK_LINGER) || (current->flags & PF_EXITING))
> > return;
> >
> > ...
> > }
>
> One note: if we ever use vsock_linger() in vsock_shutdown(), the PF_EXITING
> condition would be unnecessary checked for that caller, right?
Right, for shutdown it should always be false, so maybe better to keep
the check in the caller.
Thanks,
Stefano
>
> > Or, if we move the call to vsock_linger() in __vsock_release(), we can
> > do the check there.
> >
> > Thanks,
> > Stefano
> >
> >>
> >> if (sock_flag(sk, SOCK_DONE)) {
> >> return true;
> >>
> >> --
> >> 2.49.0
> >>
> >>
>
