| Message ID | 8baa2e3a-af6b-c0fe-9bfb-7cf89506474a@sberdevices.ru (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | vsock: updates for SO_RCVLOWAT handling | expand |
On Mon, Jul 25, 2022 at 08:05:28AM +0000, Arseniy Krasnov wrote: >This adds transport specific callback for SO_RCVLOWAT, because in some >transports it may be difficult to know current available number of bytes >ready to read. Thus, when SO_RCVLOWAT is set, transport may reject it. > >Signed-off-by: Arseniy Krasnov <AVKrasnov@sberdevices.ru> >--- > include/net/af_vsock.h | 1 + > net/vmw_vsock/af_vsock.c | 19 +++++++++++++++++++ > 2 files changed, 20 insertions(+) > >diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h >index f742e50207fb..eae5874bae35 100644 >--- a/include/net/af_vsock.h >+++ b/include/net/af_vsock.h >@@ -134,6 +134,7 @@ struct vsock_transport { > u64 (*stream_rcvhiwat)(struct vsock_sock *); > bool (*stream_is_active)(struct vsock_sock *); > bool (*stream_allow)(u32 cid, u32 port); >+ int (*set_rcvlowat)(struct vsock_sock *, int); > > /* SEQ_PACKET. */ > ssize_t (*seqpacket_dequeue)(struct vsock_sock *vsk, struct msghdr *msg, >diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c >index 63a13fa2686a..b7a286db4af1 100644 >--- a/net/vmw_vsock/af_vsock.c >+++ b/net/vmw_vsock/af_vsock.c >@@ -2130,6 +2130,24 @@ vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, > return err; > } > >+static int vsock_set_rcvlowat(struct sock *sk, int val) >+{ >+ const struct vsock_transport *transport; >+ struct vsock_sock *vsk; >+ int err = 0; >+ >+ vsk = vsock_sk(sk); >+ transport = vsk->transport; `transport` can be NULL if the user call SO_RCVLOWAT before we assign it, so we should check it. I think if the transport implements `set_rcvlowat`, maybe we should set there sk->sk_rcvlowat, so I would do something like that: if (transport && transport->set_rcvlowat) err = transport->set_rcvlowat(vsk, val); else WRITE_ONCE(sk->sk_rcvlowat, val ? : 1); return err; In addition I think we should check that val does not exceed vsk->buffer_size, something similar of what tcp_set_rcvlowat() does. Thanks, Stefano
On 27.07.2022 15:24, Stefano Garzarella wrote: > On Mon, Jul 25, 2022 at 08:05:28AM +0000, Arseniy Krasnov wrote: >> This adds transport specific callback for SO_RCVLOWAT, because in some >> transports it may be difficult to know current available number of bytes >> ready to read. Thus, when SO_RCVLOWAT is set, transport may reject it. >> >> Signed-off-by: Arseniy Krasnov <AVKrasnov@sberdevices.ru> >> --- >> include/net/af_vsock.h | 1 + >> net/vmw_vsock/af_vsock.c | 19 +++++++++++++++++++ >> 2 files changed, 20 insertions(+) >> >> diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h >> index f742e50207fb..eae5874bae35 100644 >> --- a/include/net/af_vsock.h >> +++ b/include/net/af_vsock.h >> @@ -134,6 +134,7 @@ struct vsock_transport { >> u64 (*stream_rcvhiwat)(struct vsock_sock *); >> bool (*stream_is_active)(struct vsock_sock *); >> bool (*stream_allow)(u32 cid, u32 port); >> + int (*set_rcvlowat)(struct vsock_sock *, int); >> >> /* SEQ_PACKET. */ >> ssize_t (*seqpacket_dequeue)(struct vsock_sock *vsk, struct msghdr *msg, >> diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c >> index 63a13fa2686a..b7a286db4af1 100644 >> --- a/net/vmw_vsock/af_vsock.c >> +++ b/net/vmw_vsock/af_vsock.c >> @@ -2130,6 +2130,24 @@ vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, >> return err; >> } >> >> +static int vsock_set_rcvlowat(struct sock *sk, int val) >> +{ >> + const struct vsock_transport *transport; >> + struct vsock_sock *vsk; >> + int err = 0; >> + >> + vsk = vsock_sk(sk); >> + transport = vsk->transport; > > `transport` can be NULL if the user call SO_RCVLOWAT before we assign it, so we should check it. Ack > > I think if the transport implements `set_rcvlowat`, maybe we should set there sk->sk_rcvlowat, so I would do something like that: > > if (transport && transport->set_rcvlowat) > err = transport->set_rcvlowat(vsk, val); > else > WRITE_ONCE(sk->sk_rcvlowat, val ? : 1); > > return err; > > In addition I think we should check that val does not exceed vsk->buffer_size, something similar of what tcp_set_rcvlowat() does. > Ack > Thanks, > Stefano >
diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h index f742e50207fb..eae5874bae35 100644 --- a/include/net/af_vsock.h +++ b/include/net/af_vsock.h @@ -134,6 +134,7 @@ struct vsock_transport { u64 (*stream_rcvhiwat)(struct vsock_sock *); bool (*stream_is_active)(struct vsock_sock *); bool (*stream_allow)(u32 cid, u32 port); + int (*set_rcvlowat)(struct vsock_sock *, int); /* SEQ_PACKET. */ ssize_t (*seqpacket_dequeue)(struct vsock_sock *vsk, struct msghdr *msg, diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c index 63a13fa2686a..b7a286db4af1 100644 --- a/net/vmw_vsock/af_vsock.c +++ b/net/vmw_vsock/af_vsock.c @@ -2130,6 +2130,24 @@ vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, return err; } +static int vsock_set_rcvlowat(struct sock *sk, int val) +{ + const struct vsock_transport *transport; + struct vsock_sock *vsk; + int err = 0; + + vsk = vsock_sk(sk); + transport = vsk->transport; + + if (transport->set_rcvlowat) + err = transport->set_rcvlowat(vsk, val); + + if (!err) + WRITE_ONCE(sk->sk_rcvlowat, val ? : 1); + + return err; +} + static const struct proto_ops vsock_stream_ops = { .family = PF_VSOCK, .owner = THIS_MODULE, @@ -2149,6 +2167,7 @@ static const struct proto_ops vsock_stream_ops = { .recvmsg = vsock_connectible_recvmsg, .mmap = sock_no_mmap, .sendpage = sock_no_sendpage, + .set_rcvlowat = vsock_set_rcvlowat, }; static const struct proto_ops vsock_seqpacket_ops = {
This adds transport specific callback for SO_RCVLOWAT, because in some transports it may be difficult to know current available number of bytes ready to read. Thus, when SO_RCVLOWAT is set, transport may reject it. Signed-off-by: Arseniy Krasnov <AVKrasnov@sberdevices.ru> --- include/net/af_vsock.h | 1 + net/vmw_vsock/af_vsock.c | 19 +++++++++++++++++++ 2 files changed, 20 insertions(+)