| Message ID | 20210125111200.598103-1-arseny.krasnov@kaspersky.com (mailing list archive) |
|---|---|
| State | RFC |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | virtio/vsock: introduce SOCK_SEQPACKET support | expand |
On Mon, Jan 25, 2021 at 02:11:57PM +0300, Arseny Krasnov wrote: >This prepares 'vsock_connectible_recvmg()' to call SEQPACKET receive >loop: >1) Some shared check left in this function, then socket type > specific receive loop is called. >2) Stream receive loop is moved to separate function. > >Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com> >--- > net/vmw_vsock/af_vsock.c | 242 ++++++++++++++++++++++----------------- > 1 file changed, 138 insertions(+), 104 deletions(-) > >diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c >index c9ce57db9554..524df8fc84cd 100644 >--- a/net/vmw_vsock/af_vsock.c >+++ b/net/vmw_vsock/af_vsock.c >@@ -1858,65 +1858,69 @@ static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg, > return vsock_connectible_sendmsg(sock, msg, len); > } > >- >-static int >-vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, >- int flags) >+static int vsock_wait_data(struct sock *sk, struct wait_queue_entry *wait, >+ long timeout, >+ struct vsock_transport_recv_notify_data *recv_data, >+ size_t target) > { >- struct sock *sk; >+ int err = 0; > struct vsock_sock *vsk; > const struct vsock_transport *transport; >- int err; >- size_t target; >- ssize_t copied; >- long timeout; >- struct vsock_transport_recv_notify_data recv_data; >- >- DEFINE_WAIT(wait); > >- sk = sock->sk; > vsk = vsock_sk(sk); > transport = vsk->transport; >- err = 0; >- >- lock_sock(sk); >- >- if (!transport || sk->sk_state != TCP_ESTABLISHED) { >- /* Recvmsg is supposed to return 0 if a peer performs an >- * orderly shutdown. Differentiate between that case and when a >- * peer has not connected or a local shutdown occured with the >- * SOCK_DONE flag. >- */ >- if (sock_flag(sk, SOCK_DONE)) >- err = 0; >- else >- err = -ENOTCONN; > >+ if (sk->sk_err != 0 || >+ (sk->sk_shutdown & RCV_SHUTDOWN) || >+ (vsk->peer_shutdown & SEND_SHUTDOWN)) { >+ err = -1; > goto out; > } >- >- if (flags & MSG_OOB) { >- err = -EOPNOTSUPP; >+ /* Don't wait for non-blocking sockets. */ >+ if (timeout == 0) { >+ err = -EAGAIN; > goto out; > } > >- /* We don't check peer_shutdown flag here since peer may actually shut >- * down, but there can be data in the queue that a local socket can >- * receive. >- */ >- if (sk->sk_shutdown & RCV_SHUTDOWN) { >- err = 0; >- goto out; >+ if (recv_data) { >+ err = transport->notify_recv_pre_block(vsk, target, recv_data); >+ if (err < 0) >+ goto out; > } > >- /* It is valid on Linux to pass in a zero-length receive buffer. This >- * is not an error. We may as well bail out now. >- */ >- if (!len) { >- err = 0; >+ release_sock(sk); >+ timeout = schedule_timeout(timeout); >+ lock_sock(sk); >+ >+ if (signal_pending(current)) { >+ err = sock_intr_errno(timeout); >+ goto out; >+ } else if (timeout == 0) { >+ err = -EAGAIN; > goto out; > } > >+out: >+ finish_wait(sk_sleep(sk), wait); >+ return err; >+} >+ >+static int __vsock_stream_recvmsg(struct sock *sk, struct msghdr *msg, >+ size_t len, int flags) >+{ >+ struct vsock_transport_recv_notify_data recv_data; >+ const struct vsock_transport *transport; >+ struct vsock_sock *vsk; >+ ssize_t copied; >+ size_t target; >+ long timeout; >+ int err; >+ >+ DEFINE_WAIT(wait); >+ >+ vsk = vsock_sk(sk); >+ transport = vsk->transport; >+ > /* We must not copy less than target bytes into the user's buffer > * before returning successfully, so we wait for the consume queue to > * have that much data to consume before dequeueing. Note that this >@@ -1937,85 +1941,53 @@ vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, > > > while (1) { >+ ssize_t read; > s64 ready; > > prepare_to_wait(sk_sleep(sk), &wait, > TASK_INTERRUPTIBLE); > ready = vsock_stream_has_data(vsk); Maybe we can move also these lines in vsock_wait_data() that can return 'ready' or an error. > > if (ready == 0) { >- if (sk->sk_err != 0 || >- (sk->sk_shutdown & RCV_SHUTDOWN) || >- (vsk->peer_shutdown & SEND_SHUTDOWN)) { >- finish_wait(sk_sleep(sk), &wait); >- break; >- } >- /* Don't wait for non-blocking sockets. */ >- if (timeout == 0) { >- err = -EAGAIN; >- finish_wait(sk_sleep(sk), &wait); >- break; >- } >- >- err = transport->notify_recv_pre_block( >- vsk, target, &recv_data); >- if (err < 0) { >- finish_wait(sk_sleep(sk), &wait); >- break; >- } >- release_sock(sk); >- timeout = schedule_timeout(timeout); >- lock_sock(sk); >- >- if (signal_pending(current)) { >- err = sock_intr_errno(timeout); >- finish_wait(sk_sleep(sk), &wait); >- break; >- } else if (timeout == 0) { >- err = -EAGAIN; >- finish_wait(sk_sleep(sk), &wait); >+ if (vsock_wait_data(sk, &wait, timeout, &recv_data, target)) > break; >- } >- } else { >- ssize_t read; >+ continue; >+ } > >- finish_wait(sk_sleep(sk), &wait); >+ finish_wait(sk_sleep(sk), &wait); And also this one can be moved in vsock_wait_data(). > >- if (ready < 0) { >- /* Invalid queue pair content. XXX This should >- * be changed to a connection reset in a later >- * change. >- */ >+ if (ready < 0) { >+ /* Invalid queue pair content. XXX This should >+ * be changed to a connection reset in a later >+ * change. >+ */ > >- err = -ENOMEM; >- goto out; >- } >+ err = -ENOMEM; >+ goto out; >+ } > >- err = transport->notify_recv_pre_dequeue( >- vsk, target, &recv_data); >- if (err < 0) >- break; >+ err = transport->notify_recv_pre_dequeue(vsk, >+ target, &recv_data); >+ if (err < 0) >+ break; >+ read = transport->stream_dequeue(vsk, msg, len - copied, flags); > >- read = transport->stream_dequeue( >- vsk, msg, >- len - copied, flags); >- if (read < 0) { >- err = -ENOMEM; >- break; >- } >+ if (read < 0) { >+ err = -ENOMEM; >+ break; >+ } > >- copied += read; >+ copied += read; > >- err = transport->notify_recv_post_dequeue( >- vsk, target, read, >+ err = transport->notify_recv_post_dequeue(vsk, >+ target, read, > !(flags & MSG_PEEK), &recv_data); >- if (err < 0) >- goto out; >+ if (err < 0) >+ goto out; > >- if (read >= target || flags & MSG_PEEK) >- break; >+ if (read >= target || flags & MSG_PEEK) >+ break; > >- target -= read; >- } >+ target -= read; > } > > if (sk->sk_err) >@@ -2031,6 +2003,68 @@ vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, > return err; > } > >+static int __vsock_seqpacket_recvmsg(struct sock *sk, struct msghdr *msg, >+ size_t len, int flags) >+{ >+ return -1; >+} >+ You can add this function later, when you implement it... >+static int >+vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, >+ int flags) >+{ >+ const struct vsock_transport *transport; >+ struct vsock_sock *vsk; >+ struct sock *sk; >+ int err = 0; >+ >+ sk = sock->sk; >+ >+ lock_sock(sk); >+ >+ vsk = vsock_sk(sk); >+ transport = vsk->transport; >+ >+ if (!transport || sk->sk_state != TCP_ESTABLISHED) { >+ /* Recvmsg is supposed to return 0 if a peer performs an >+ * orderly shutdown. Differentiate between that case and when a >+ * peer has not connected or a local shutdown occurred >with the >+ * SOCK_DONE flag. >+ */ >+ if (!sock_flag(sk, SOCK_DONE)) >+ err = -ENOTCONN; >+ >+ goto out; >+ } >+ >+ if (flags & MSG_OOB) { >+ err = -EOPNOTSUPP; >+ goto out; >+ } >+ >+ /* We don't check peer_shutdown flag here since peer may actually shut >+ * down, but there can be data in the queue that a local socket can >+ * receive. >+ */ >+ if (sk->sk_shutdown & RCV_SHUTDOWN) >+ goto out; >+ >+ /* It is valid on Linux to pass in a zero-length receive buffer. This >+ * is not an error. We may as well bail out now. >+ */ >+ if (!len) >+ goto out; >+ >+ if (sk->sk_type == SOCK_STREAM) >+ err = __vsock_stream_recvmsg(sk, msg, len, flags); >+ else >+ err = __vsock_seqpacket_recvmsg(sk, msg, len, flags); ...and also this 'else' branch. >+ >+out: >+ release_sock(sk); >+ return err; >+} >+ > static int > vsock_stream_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, > int flags) >-- >2.25.1 >
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c index c9ce57db9554..524df8fc84cd 100644 --- a/net/vmw_vsock/af_vsock.c +++ b/net/vmw_vsock/af_vsock.c @@ -1858,65 +1858,69 @@ static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg, return vsock_connectible_sendmsg(sock, msg, len); } - -static int -vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, - int flags) +static int vsock_wait_data(struct sock *sk, struct wait_queue_entry *wait, + long timeout, + struct vsock_transport_recv_notify_data *recv_data, + size_t target) { - struct sock *sk; + int err = 0; struct vsock_sock *vsk; const struct vsock_transport *transport; - int err; - size_t target; - ssize_t copied; - long timeout; - struct vsock_transport_recv_notify_data recv_data; - - DEFINE_WAIT(wait); - sk = sock->sk; vsk = vsock_sk(sk); transport = vsk->transport; - err = 0; - - lock_sock(sk); - - if (!transport || sk->sk_state != TCP_ESTABLISHED) { - /* Recvmsg is supposed to return 0 if a peer performs an - * orderly shutdown. Differentiate between that case and when a - * peer has not connected or a local shutdown occured with the - * SOCK_DONE flag. - */ - if (sock_flag(sk, SOCK_DONE)) - err = 0; - else - err = -ENOTCONN; + if (sk->sk_err != 0 || + (sk->sk_shutdown & RCV_SHUTDOWN) || + (vsk->peer_shutdown & SEND_SHUTDOWN)) { + err = -1; goto out; } - - if (flags & MSG_OOB) { - err = -EOPNOTSUPP; + /* Don't wait for non-blocking sockets. */ + if (timeout == 0) { + err = -EAGAIN; goto out; } - /* We don't check peer_shutdown flag here since peer may actually shut - * down, but there can be data in the queue that a local socket can - * receive. - */ - if (sk->sk_shutdown & RCV_SHUTDOWN) { - err = 0; - goto out; + if (recv_data) { + err = transport->notify_recv_pre_block(vsk, target, recv_data); + if (err < 0) + goto out; } - /* It is valid on Linux to pass in a zero-length receive buffer. This - * is not an error. We may as well bail out now. - */ - if (!len) { - err = 0; + release_sock(sk); + timeout = schedule_timeout(timeout); + lock_sock(sk); + + if (signal_pending(current)) { + err = sock_intr_errno(timeout); + goto out; + } else if (timeout == 0) { + err = -EAGAIN; goto out; } +out: + finish_wait(sk_sleep(sk), wait); + return err; +} + +static int __vsock_stream_recvmsg(struct sock *sk, struct msghdr *msg, + size_t len, int flags) +{ + struct vsock_transport_recv_notify_data recv_data; + const struct vsock_transport *transport; + struct vsock_sock *vsk; + ssize_t copied; + size_t target; + long timeout; + int err; + + DEFINE_WAIT(wait); + + vsk = vsock_sk(sk); + transport = vsk->transport; + /* We must not copy less than target bytes into the user's buffer * before returning successfully, so we wait for the consume queue to * have that much data to consume before dequeueing. Note that this @@ -1937,85 +1941,53 @@ vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, while (1) { + ssize_t read; s64 ready; prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); ready = vsock_stream_has_data(vsk); if (ready == 0) { - if (sk->sk_err != 0 || - (sk->sk_shutdown & RCV_SHUTDOWN) || - (vsk->peer_shutdown & SEND_SHUTDOWN)) { - finish_wait(sk_sleep(sk), &wait); - break; - } - /* Don't wait for non-blocking sockets. */ - if (timeout == 0) { - err = -EAGAIN; - finish_wait(sk_sleep(sk), &wait); - break; - } - - err = transport->notify_recv_pre_block( - vsk, target, &recv_data); - if (err < 0) { - finish_wait(sk_sleep(sk), &wait); - break; - } - release_sock(sk); - timeout = schedule_timeout(timeout); - lock_sock(sk); - - if (signal_pending(current)) { - err = sock_intr_errno(timeout); - finish_wait(sk_sleep(sk), &wait); - break; - } else if (timeout == 0) { - err = -EAGAIN; - finish_wait(sk_sleep(sk), &wait); + if (vsock_wait_data(sk, &wait, timeout, &recv_data, target)) break; - } - } else { - ssize_t read; + continue; + } - finish_wait(sk_sleep(sk), &wait); + finish_wait(sk_sleep(sk), &wait); - if (ready < 0) { - /* Invalid queue pair content. XXX This should - * be changed to a connection reset in a later - * change. - */ + if (ready < 0) { + /* Invalid queue pair content. XXX This should + * be changed to a connection reset in a later + * change. + */ - err = -ENOMEM; - goto out; - } + err = -ENOMEM; + goto out; + } - err = transport->notify_recv_pre_dequeue( - vsk, target, &recv_data); - if (err < 0) - break; + err = transport->notify_recv_pre_dequeue(vsk, + target, &recv_data); + if (err < 0) + break; + read = transport->stream_dequeue(vsk, msg, len - copied, flags); - read = transport->stream_dequeue( - vsk, msg, - len - copied, flags); - if (read < 0) { - err = -ENOMEM; - break; - } + if (read < 0) { + err = -ENOMEM; + break; + } - copied += read; + copied += read; - err = transport->notify_recv_post_dequeue( - vsk, target, read, + err = transport->notify_recv_post_dequeue(vsk, + target, read, !(flags & MSG_PEEK), &recv_data); - if (err < 0) - goto out; + if (err < 0) + goto out; - if (read >= target || flags & MSG_PEEK) - break; + if (read >= target || flags & MSG_PEEK) + break; - target -= read; - } + target -= read; } if (sk->sk_err) @@ -2031,6 +2003,68 @@ vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, return err; } +static int __vsock_seqpacket_recvmsg(struct sock *sk, struct msghdr *msg, + size_t len, int flags) +{ + return -1; +} + +static int +vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, + int flags) +{ + const struct vsock_transport *transport; + struct vsock_sock *vsk; + struct sock *sk; + int err = 0; + + sk = sock->sk; + + lock_sock(sk); + + vsk = vsock_sk(sk); + transport = vsk->transport; + + if (!transport || sk->sk_state != TCP_ESTABLISHED) { + /* Recvmsg is supposed to return 0 if a peer performs an + * orderly shutdown. Differentiate between that case and when a + * peer has not connected or a local shutdown occurred with the + * SOCK_DONE flag. + */ + if (!sock_flag(sk, SOCK_DONE)) + err = -ENOTCONN; + + goto out; + } + + if (flags & MSG_OOB) { + err = -EOPNOTSUPP; + goto out; + } + + /* We don't check peer_shutdown flag here since peer may actually shut + * down, but there can be data in the queue that a local socket can + * receive. + */ + if (sk->sk_shutdown & RCV_SHUTDOWN) + goto out; + + /* It is valid on Linux to pass in a zero-length receive buffer. This + * is not an error. We may as well bail out now. + */ + if (!len) + goto out; + + if (sk->sk_type == SOCK_STREAM) + err = __vsock_stream_recvmsg(sk, msg, len, flags); + else + err = __vsock_seqpacket_recvmsg(sk, msg, len, flags); + +out: + release_sock(sk); + return err; +} + static int vsock_stream_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, int flags)
This prepares 'vsock_connectible_recvmg()' to call SEQPACKET receive loop: 1) Some shared check left in this function, then socket type specific receive loop is called. 2) Stream receive loop is moved to separate function. Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com> --- net/vmw_vsock/af_vsock.c | 242 ++++++++++++++++++++++----------------- 1 file changed, 138 insertions(+), 104 deletions(-)