From: Bobby Eshleman <bobby.eshleman@xxxxxxxxxxxxx> This commit implements the common function virtio_transport_dgram_enqueue for enqueueing datagrams. It does not add usage in either vhost or virtio yet. Signed-off-by: Bobby Eshleman <bobby.eshleman@xxxxxxxxxxxxx> Signed-off-by: Amery Hung <amery.hung@xxxxxxxxxxxxx> --- include/linux/virtio_vsock.h | 1 + include/net/af_vsock.h | 2 + net/vmw_vsock/af_vsock.c | 2 +- net/vmw_vsock/virtio_transport_common.c | 87 ++++++++++++++++++++++++- 4 files changed, 90 insertions(+), 2 deletions(-) diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h index f749a066af46..4408749febd2 100644 --- a/include/linux/virtio_vsock.h +++ b/include/linux/virtio_vsock.h @@ -152,6 +152,7 @@ struct virtio_vsock_pkt_info { u16 op; u32 flags; bool reply; + u8 remote_flags; }; struct virtio_transport { diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h index 44db8f2c507d..6e97d344ac75 100644 --- a/include/net/af_vsock.h +++ b/include/net/af_vsock.h @@ -216,6 +216,8 @@ 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); +const struct vsock_transport *vsock_dgram_lookup_transport(unsigned int cid, + __u8 flags); struct vsock_skb_cb { unsigned int src_cid; diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c index ab08cd81720e..f83b655fdbe9 100644 --- a/net/vmw_vsock/af_vsock.c +++ b/net/vmw_vsock/af_vsock.c @@ -487,7 +487,7 @@ vsock_connectible_lookup_transport(unsigned int cid, __u8 flags) return transport; } -static const struct vsock_transport * +const struct vsock_transport * vsock_dgram_lookup_transport(unsigned int cid, __u8 flags) { const struct vsock_transport *transport; diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c index a1c76836d798..46cd1807f8e3 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -1040,13 +1040,98 @@ int virtio_transport_shutdown(struct vsock_sock *vsk, int mode) } EXPORT_SYMBOL_GPL(virtio_transport_shutdown); +static int virtio_transport_dgram_send_pkt_info(struct vsock_sock *vsk, + struct virtio_vsock_pkt_info *info) +{ + u32 src_cid, src_port, dst_cid, dst_port; + const struct vsock_transport *transport; + const struct virtio_transport *t_ops; + struct sock *sk = sk_vsock(vsk); + struct virtio_vsock_hdr *hdr; + struct sk_buff *skb; + void *payload; + int noblock = 0; + int err; + + info->type = virtio_transport_get_type(sk_vsock(vsk)); + + if (info->pkt_len > VIRTIO_VSOCK_MAX_PKT_BUF_SIZE) + return -EMSGSIZE; + + transport = vsock_dgram_lookup_transport(info->remote_cid, info->remote_flags); + t_ops = container_of(transport, struct virtio_transport, transport); + if (unlikely(!t_ops)) + return -EFAULT; + + if (info->msg) + noblock = info->msg->msg_flags & MSG_DONTWAIT; + + /* Use sock_alloc_send_skb to throttle by sk_sndbuf. This helps avoid + * triggering the OOM. + */ + skb = sock_alloc_send_skb(sk, info->pkt_len + VIRTIO_VSOCK_SKB_HEADROOM, + noblock, &err); + if (!skb) + return err; + + skb_reserve(skb, VIRTIO_VSOCK_SKB_HEADROOM); + + src_cid = t_ops->transport.get_local_cid(); + src_port = vsk->local_addr.svm_port; + dst_cid = info->remote_cid; + dst_port = info->remote_port; + + hdr = virtio_vsock_hdr(skb); + hdr->type = cpu_to_le16(info->type); + hdr->op = cpu_to_le16(info->op); + hdr->src_cid = cpu_to_le64(src_cid); + hdr->dst_cid = cpu_to_le64(dst_cid); + hdr->src_port = cpu_to_le32(src_port); + hdr->dst_port = cpu_to_le32(dst_port); + hdr->flags = cpu_to_le32(info->flags); + hdr->len = cpu_to_le32(info->pkt_len); + + if (info->msg && info->pkt_len > 0) { + payload = skb_put(skb, info->pkt_len); + err = memcpy_from_msg(payload, info->msg, info->pkt_len); + if (err) + goto out; + } + + trace_virtio_transport_alloc_pkt(src_cid, src_port, + dst_cid, dst_port, + info->pkt_len, + info->type, + info->op, + info->flags, + false); + + return t_ops->send_pkt(skb); +out: + kfree_skb(skb); + return err; +} + int virtio_transport_dgram_enqueue(struct vsock_sock *vsk, struct sockaddr_vm *remote_addr, struct msghdr *msg, size_t dgram_len) { - return -EOPNOTSUPP; + /* Here we are only using the info struct to retain style uniformity + * and to ease future refactoring and merging. + */ + struct virtio_vsock_pkt_info info = { + .op = VIRTIO_VSOCK_OP_RW, + .remote_cid = remote_addr->svm_cid, + .remote_port = remote_addr->svm_port, + .remote_flags = remote_addr->svm_flags, + .msg = msg, + .vsk = vsk, + .pkt_len = dgram_len, + }; + + return virtio_transport_dgram_send_pkt_info(vsk, &info); } EXPORT_SYMBOL_GPL(virtio_transport_dgram_enqueue); -- 2.20.1