[RFC PATCH v5 12/19] virtio/vsock: fetch length for SEQPACKET record
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STALE2044d
From: Arseny Krasnov <hidden>
Date: 2021-02-18 05:56:16
Also in:
kvm, lkml
Subsystem:
networking [general], the rest, virtio and vhost vsock driver, virtio core, vm sockets (af_vsock) · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Stefan Hajnoczi, Stefano Garzarella, "Michael S. Tsirkin", Jason Wang, Eugenio Pérez
Revision v5 of 9 in this series.
Revisions (9)
This adds transport callback which tries to fetch record begin marker from socket's rx queue. It is called from af_vsock.c before reading data packets of record. Signed-off-by: Arseny Krasnov <redacted> --- include/linux/virtio_vsock.h | 1 + net/vmw_vsock/virtio_transport_common.c | 53 +++++++++++++++++++++++++ 2 files changed, 54 insertions(+)
diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h
index 003d06ae4a85..022667d57884 100644
--- a/include/linux/virtio_vsock.h
+++ b/include/linux/virtio_vsock.h@@ -85,6 +85,7 @@ virtio_transport_dgram_dequeue(struct vsock_sock *vsk, struct msghdr *msg, size_t len, 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,
diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
index d8ec2dfa2315..e9a2de72ebbf 100644
--- a/net/vmw_vsock/virtio_transport_common.c
+++ b/net/vmw_vsock/virtio_transport_common.c@@ -399,6 +399,59 @@ static inline void virtio_transport_remove_pkt(struct virtio_vsock_pkt *pkt) virtio_transport_free_pkt(pkt); } +static size_t virtio_transport_drop_until_seq_begin(struct virtio_vsock_sock *vvs) +{ + struct virtio_vsock_pkt *pkt, *n; + size_t bytes_dropped = 0; + + list_for_each_entry_safe(pkt, n, &vvs->rx_queue, list) { + if (le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_SEQ_BEGIN) + break; + + bytes_dropped += le32_to_cpu(pkt->hdr.len); + virtio_transport_dec_rx_pkt(vvs, pkt); + virtio_transport_remove_pkt(pkt); + } + + return bytes_dropped; +} + +size_t virtio_transport_seqpacket_seq_get_len(struct vsock_sock *vsk) +{ + struct virtio_vsock_seq_hdr *seq_hdr; + struct virtio_vsock_sock *vvs; + struct virtio_vsock_pkt *pkt; + size_t bytes_dropped; + + vvs = vsk->trans; + + spin_lock_bh(&vvs->rx_lock); + + /* Fetch all orphaned 'RW' packets and send credit update. */ + bytes_dropped = virtio_transport_drop_until_seq_begin(vvs); + + if (list_empty(&vvs->rx_queue)) + goto out; + + pkt = list_first_entry(&vvs->rx_queue, struct virtio_vsock_pkt, list); + + vvs->user_read_copied = 0; + + seq_hdr = (struct virtio_vsock_seq_hdr *)pkt->buf; + vvs->user_read_seq_len = le32_to_cpu(seq_hdr->msg_len); + vvs->curr_rx_msg_cnt = le32_to_cpu(seq_hdr->msg_cnt); + virtio_transport_dec_rx_pkt(vvs, pkt); + virtio_transport_remove_pkt(pkt); +out: + spin_unlock_bh(&vvs->rx_lock); + + if (bytes_dropped) + virtio_transport_send_credit_update(vsk); + + return vvs->user_read_seq_len; +} +EXPORT_SYMBOL_GPL(virtio_transport_seqpacket_seq_get_len); + static int virtio_transport_seqpacket_do_dequeue(struct vsock_sock *vsk, struct msghdr *msg, bool *msg_ready)
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2.25.1