[RFC PATCH v6 05/22] af_vsock: separate wait space loop
From: Arseny Krasnov <hidden>
Date: 2021-03-07 18:01:15
Also in:
kvm, lkml
Subsystem:
networking [general], the rest, vm sockets (af_vsock) · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Stefano Garzarella
This moves loop that waits for space on send to separate function, because it will be used for SEQ_BEGIN/SEQ_END sending before and after data transmission. Waiting for SEQ_BEGIN/SEQ_END is needed because such packets carries SEQPACKET header that couldn't be fragmented by credit mechanism, so to avoid it, sender waits until enough space will be ready. Signed-off-by: Arseny Krasnov <redacted> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> --- include/net/af_vsock.h | 2 + net/vmw_vsock/af_vsock.c | 99 +++++++++++++++++++++++++--------------- 2 files changed, 63 insertions(+), 38 deletions(-)
diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h
index 5ad7ee7f78fd..a8c4039e40cf 100644
--- a/include/net/af_vsock.h
+++ b/include/net/af_vsock.h@@ -205,6 +205,8 @@ 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); +int vsock_wait_space(struct sock *sk, size_t space, int flags, + struct vsock_transport_send_notify_data *send_data); /**** TAP ****/
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index ac2f69362f2e..5bf64a3e678a 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c@@ -1692,6 +1692,65 @@ static int vsock_connectible_getsockopt(struct socket *sock, return 0; } +int vsock_wait_space(struct sock *sk, size_t space, int flags, + struct vsock_transport_send_notify_data *send_data) +{ + const struct vsock_transport *transport; + struct vsock_sock *vsk; + long timeout; + int err; + + DEFINE_WAIT_FUNC(wait, woken_wake_function); + + vsk = vsock_sk(sk); + transport = vsk->transport; + timeout = sock_sndtimeo(sk, flags & MSG_DONTWAIT); + err = 0; + + add_wait_queue(sk_sleep(sk), &wait); + + while (vsock_stream_has_space(vsk) < space && + sk->sk_err == 0 && + !(sk->sk_shutdown & SEND_SHUTDOWN) && + !(vsk->peer_shutdown & RCV_SHUTDOWN)) { + + /* Don't wait for non-blocking sockets. */ + if (timeout == 0) { + err = -EAGAIN; + goto out_err; + } + + if (send_data) { + err = transport->notify_send_pre_block(vsk, send_data); + if (err < 0) + goto out_err; + } + + release_sock(sk); + timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); + lock_sock(sk); + if (signal_pending(current)) { + err = sock_intr_errno(timeout); + goto out_err; + } else if (timeout == 0) { + err = -EAGAIN; + goto out_err; + } + } + + if (sk->sk_err) { + err = -sk->sk_err; + } else if ((sk->sk_shutdown & SEND_SHUTDOWN) || + (vsk->peer_shutdown & RCV_SHUTDOWN)) { + err = -EPIPE; + } + +out_err: + remove_wait_queue(sk_sleep(sk), &wait); + return err; +} +EXPORT_SYMBOL_GPL(vsock_wait_space); + static int vsock_connectible_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) {
@@ -1699,10 +1758,8 @@ static int vsock_connectible_sendmsg(struct socket *sock, struct msghdr *msg, struct vsock_sock *vsk; const struct vsock_transport *transport; ssize_t total_written; - long timeout; int err; struct vsock_transport_send_notify_data send_data; - DEFINE_WAIT_FUNC(wait, woken_wake_function); sk = sock->sk; vsk = vsock_sk(sk);
@@ -1740,9 +1797,6 @@ static int vsock_connectible_sendmsg(struct socket *sock, struct msghdr *msg, goto out; } - /* Wait for room in the produce queue to enqueue our user's data. */ - timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); - err = transport->notify_send_init(vsk, &send_data); if (err < 0) goto out;
@@ -1750,39 +1804,8 @@ static int vsock_connectible_sendmsg(struct socket *sock, struct msghdr *msg, while (total_written < len) { ssize_t written; - add_wait_queue(sk_sleep(sk), &wait); - while (vsock_stream_has_space(vsk) == 0 && - sk->sk_err == 0 && - !(sk->sk_shutdown & SEND_SHUTDOWN) && - !(vsk->peer_shutdown & RCV_SHUTDOWN)) { - - /* Don't wait for non-blocking sockets. */ - if (timeout == 0) { - err = -EAGAIN; - remove_wait_queue(sk_sleep(sk), &wait); - goto out_err; - } - - err = transport->notify_send_pre_block(vsk, &send_data); - if (err < 0) { - remove_wait_queue(sk_sleep(sk), &wait); - goto out_err; - } - - release_sock(sk); - timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout); - lock_sock(sk); - if (signal_pending(current)) { - err = sock_intr_errno(timeout); - remove_wait_queue(sk_sleep(sk), &wait); - goto out_err; - } else if (timeout == 0) { - err = -EAGAIN; - remove_wait_queue(sk_sleep(sk), &wait); - goto out_err; - } - } - remove_wait_queue(sk_sleep(sk), &wait); + if (vsock_wait_space(sk, 1, msg->msg_flags, &send_data)) + goto out_err; /* These checks occur both as part of and after the loop * conditional since we need to check before and after
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2.25.1