Re: [RFC PATCH v4 12/17] virtio/vsock: rest of SOCK_SEQPACKET support

From: Arseny Krasnov
Date: Thu Feb 11 2021 - 06:31:55 EST


On 07.02.2021 18:17, Arseny Krasnov wrote:
> This adds rest of logic for SEQPACKET:
> 1) Packet's type is now set in 'virtio_send_pkt_info()' using
> type of socket.
> 2) SEQPACKET specific functions which send SEQ_BEGIN/SEQ_END.
> Note that both functions may sleep to wait enough space for
> SEQPACKET header.
> 3) SEQ_BEGIN/SEQ_END to TAP packet capture.
> 4) Send SHUTDOWN on socket close for SEQPACKET type.
>
> Signed-off-by: Arseny Krasnov <arseny.krasnov@xxxxxxxxxxxxx>
> ---
> include/linux/virtio_vsock.h | 9 +++
> net/vmw_vsock/virtio_transport_common.c | 99 +++++++++++++++++++++----
> 2 files changed, 95 insertions(+), 13 deletions(-)
>
> diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h
> index a5e8681bfc6a..c4a39424686d 100644
> --- a/include/linux/virtio_vsock.h
> +++ b/include/linux/virtio_vsock.h
> @@ -41,6 +41,7 @@ struct virtio_vsock_sock {
> u32 user_read_seq_len;
> u32 user_read_copied;
> u32 curr_rx_msg_cnt;
> + u32 next_tx_msg_cnt;
> };
>
> struct virtio_vsock_pkt {
> @@ -85,7 +86,15 @@ virtio_transport_dgram_dequeue(struct vsock_sock *vsk,
> struct msghdr *msg,
> size_t len, int flags);
>
> +int virtio_transport_seqpacket_seq_send_len(struct vsock_sock *vsk, size_t len, int flags);
> +int virtio_transport_seqpacket_seq_send_eor(struct vsock_sock *vsk, int flags);
> size_t virtio_transport_seqpacket_seq_get_len(struct vsock_sock *vsk);
> +int
> +virtio_transport_seqpacket_dequeue(struct vsock_sock *vsk,
> + struct msghdr *msg,
> + int flags,
> + bool *msg_ready);
> +
> s64 virtio_transport_stream_has_data(struct vsock_sock *vsk);
> s64 virtio_transport_stream_has_space(struct vsock_sock *vsk);
>
> diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
> index 51b66f8dd7c7..0aa0fd33e9d6 100644
> --- a/net/vmw_vsock/virtio_transport_common.c
> +++ b/net/vmw_vsock/virtio_transport_common.c
> @@ -139,6 +139,8 @@ static struct sk_buff *virtio_transport_build_skb(void *opaque)
> break;
> case VIRTIO_VSOCK_OP_CREDIT_UPDATE:
> case VIRTIO_VSOCK_OP_CREDIT_REQUEST:
> + case VIRTIO_VSOCK_OP_SEQ_BEGIN:
> + case VIRTIO_VSOCK_OP_SEQ_END:
> hdr->op = cpu_to_le16(AF_VSOCK_OP_CONTROL);
> break;
> default:
> @@ -165,6 +167,14 @@ void virtio_transport_deliver_tap_pkt(struct virtio_vsock_pkt *pkt)
> }
> EXPORT_SYMBOL_GPL(virtio_transport_deliver_tap_pkt);
>
> +static u16 virtio_transport_get_type(struct sock *sk)
> +{
> + if (sk->sk_type == SOCK_STREAM)
> + return VIRTIO_VSOCK_TYPE_STREAM;
> + else
> + return VIRTIO_VSOCK_TYPE_SEQPACKET;
> +}
> +
> /* This function can only be used on connecting/connected sockets,
> * since a socket assigned to a transport is required.
> *
> @@ -179,6 +189,13 @@ static int virtio_transport_send_pkt_info(struct vsock_sock *vsk,
> struct virtio_vsock_pkt *pkt;
> u32 pkt_len = info->pkt_len;
>
> + info->type = virtio_transport_get_type(sk_vsock(vsk));
> +
> + if (info->type == VIRTIO_VSOCK_TYPE_SEQPACKET &&
> + info->msg &&
> + info->msg->msg_flags & MSG_EOR)
> + info->flags |= VIRTIO_VSOCK_RW_EOR;
> +
> t_ops = virtio_transport_get_ops(vsk);
> if (unlikely(!t_ops))
> return -EFAULT;
> @@ -397,13 +414,61 @@ virtio_transport_stream_do_dequeue(struct vsock_sock *vsk,
> return err;
> }
>
> -static u16 virtio_transport_get_type(struct sock *sk)
> +static int virtio_transport_seqpacket_send_ctrl(struct vsock_sock *vsk,
> + int type,
> + size_t len,
> + int flags)
> {
> - if (sk->sk_type == SOCK_STREAM)
> - return VIRTIO_VSOCK_TYPE_STREAM;
> - else
> - return VIRTIO_VSOCK_TYPE_SEQPACKET;
> + struct virtio_vsock_sock *vvs = vsk->trans;
> + struct virtio_vsock_pkt_info info = {
> + .op = type,
> + .vsk = vsk,
> + .pkt_len = sizeof(struct virtio_vsock_seq_hdr)
> + };
> +
> + struct virtio_vsock_seq_hdr seq_hdr = {
> + .msg_cnt = vvs->next_tx_msg_cnt,
> + .msg_len = len
Oops, forgot to use 'cpu_to_le32()'. Will fix in v5
> + };
> +
> + struct kvec seq_hdr_kiov = {
> + .iov_base = (void *)&seq_hdr,
> + .iov_len = sizeof(struct virtio_vsock_seq_hdr)
> + };
> +
> + struct msghdr msg = {0};
> +
> + //XXX: do we need 'vsock_transport_send_notify_data' pointer?
> + if (vsock_wait_space(sk_vsock(vsk),
> + sizeof(struct virtio_vsock_seq_hdr),
> + flags, NULL))
> + return -1;
> +
> + iov_iter_kvec(&msg.msg_iter, WRITE, &seq_hdr_kiov, 1, sizeof(seq_hdr));
> +
> + info.msg = &msg;
> + vvs->next_tx_msg_cnt++;
> +
> + return virtio_transport_send_pkt_info(vsk, &info);
> +}
> +
> +int virtio_transport_seqpacket_seq_send_len(struct vsock_sock *vsk, size_t len, int flags)
> +{
> + return virtio_transport_seqpacket_send_ctrl(vsk,
> + VIRTIO_VSOCK_OP_SEQ_BEGIN,
> + len,
> + flags);
> }
> +EXPORT_SYMBOL_GPL(virtio_transport_seqpacket_seq_send_len);
> +
> +int virtio_transport_seqpacket_seq_send_eor(struct vsock_sock *vsk, int flags)
> +{
> + return virtio_transport_seqpacket_send_ctrl(vsk,
> + VIRTIO_VSOCK_OP_SEQ_END,
> + 0,
> + flags);
> +}
> +EXPORT_SYMBOL_GPL(virtio_transport_seqpacket_seq_send_eor);
>
> static inline void virtio_transport_remove_pkt(struct virtio_vsock_pkt *pkt)
> {
> @@ -577,6 +642,18 @@ virtio_transport_stream_dequeue(struct vsock_sock *vsk,
> }
> EXPORT_SYMBOL_GPL(virtio_transport_stream_dequeue);
>
> +int
> +virtio_transport_seqpacket_dequeue(struct vsock_sock *vsk,
> + struct msghdr *msg,
> + int flags, bool *msg_ready)
> +{
> + if (flags & MSG_PEEK)
> + return -EOPNOTSUPP;
> +
> + return virtio_transport_seqpacket_do_dequeue(vsk, msg, msg_ready);
> +}
> +EXPORT_SYMBOL_GPL(virtio_transport_seqpacket_dequeue);
> +
> int
> virtio_transport_dgram_dequeue(struct vsock_sock *vsk,
> struct msghdr *msg,
> @@ -658,14 +735,15 @@ EXPORT_SYMBOL_GPL(virtio_transport_do_socket_init);
> void virtio_transport_notify_buffer_size(struct vsock_sock *vsk, u64 *val)
> {
> struct virtio_vsock_sock *vvs = vsk->trans;
> + int type;
>
> if (*val > VIRTIO_VSOCK_MAX_BUF_SIZE)
> *val = VIRTIO_VSOCK_MAX_BUF_SIZE;
>
> vvs->buf_alloc = *val;
>
> - virtio_transport_send_credit_update(vsk, VIRTIO_VSOCK_TYPE_STREAM,
> - NULL);
> + type = virtio_transport_get_type(sk_vsock(vsk));
> + virtio_transport_send_credit_update(vsk, type, NULL);
> }
> EXPORT_SYMBOL_GPL(virtio_transport_notify_buffer_size);
>
> @@ -792,7 +870,6 @@ int virtio_transport_connect(struct vsock_sock *vsk)
> {
> struct virtio_vsock_pkt_info info = {
> .op = VIRTIO_VSOCK_OP_REQUEST,
> - .type = VIRTIO_VSOCK_TYPE_STREAM,
> .vsk = vsk,
> };
>
> @@ -804,7 +881,6 @@ int virtio_transport_shutdown(struct vsock_sock *vsk, int mode)
> {
> struct virtio_vsock_pkt_info info = {
> .op = VIRTIO_VSOCK_OP_SHUTDOWN,
> - .type = VIRTIO_VSOCK_TYPE_STREAM,
> .flags = (mode & RCV_SHUTDOWN ?
> VIRTIO_VSOCK_SHUTDOWN_RCV : 0) |
> (mode & SEND_SHUTDOWN ?
> @@ -833,7 +909,6 @@ virtio_transport_stream_enqueue(struct vsock_sock *vsk,
> {
> struct virtio_vsock_pkt_info info = {
> .op = VIRTIO_VSOCK_OP_RW,
> - .type = VIRTIO_VSOCK_TYPE_STREAM,
> .msg = msg,
> .pkt_len = len,
> .vsk = vsk,
> @@ -856,7 +931,6 @@ static int virtio_transport_reset(struct vsock_sock *vsk,
> {
> struct virtio_vsock_pkt_info info = {
> .op = VIRTIO_VSOCK_OP_RST,
> - .type = VIRTIO_VSOCK_TYPE_STREAM,
> .reply = !!pkt,
> .vsk = vsk,
> };
> @@ -1001,7 +1075,7 @@ void virtio_transport_release(struct vsock_sock *vsk)
> struct sock *sk = &vsk->sk;
> bool remove_sock = true;
>
> - if (sk->sk_type == SOCK_STREAM)
> + if (sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET)
> remove_sock = virtio_transport_close(vsk);
>
> list_for_each_entry_safe(pkt, tmp, &vvs->rx_queue, list) {
> @@ -1164,7 +1238,6 @@ virtio_transport_send_response(struct vsock_sock *vsk,
> {
> struct virtio_vsock_pkt_info info = {
> .op = VIRTIO_VSOCK_OP_RESPONSE,
> - .type = VIRTIO_VSOCK_TYPE_STREAM,
> .remote_cid = le64_to_cpu(pkt->hdr.src_cid),
> .remote_port = le32_to_cpu(pkt->hdr.src_port),
> .reply = true,