Stefano Garzarella
2021-Jun-03 15:34 UTC
[PATCH v10 15/18] vhost/vsock: support SEQPACKET for transport
On Thu, May 20, 2021 at 10:19:13PM +0300, Arseny Krasnov wrote: Please describe better the changes included in this patch in the first part of the commit message.>As vhost places data in buffers of guest's rx queue, keep SEQ_EOR >bit set only when last piece of data is copied. Otherwise we get >sequence packets for one socket in guest's rx queue with SEQ_EOR bit >set. Also remove ignore of non-stream type of packets, handle SEQPACKET >feature bit. > >Signed-off-by: Arseny Krasnov <arseny.krasnov at kaspersky.com> >--- > v9 -> v10: > 1) Move 'restore_flag' handling to 'payload_len' calculation > block. > > drivers/vhost/vsock.c | 44 +++++++++++++++++++++++++++++++++++++++---- > 1 file changed, 40 insertions(+), 4 deletions(-) > >diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c >index 5e78fb719602..63d15beaad05 100644 >--- a/drivers/vhost/vsock.c >+++ b/drivers/vhost/vsock.c >@@ -31,7 +31,8 @@ > > enum { > VHOST_VSOCK_FEATURES = VHOST_FEATURES | >- (1ULL << VIRTIO_F_ACCESS_PLATFORM) >+ (1ULL << VIRTIO_F_ACCESS_PLATFORM) | >+ (1ULL << VIRTIO_VSOCK_F_SEQPACKET) > }; > > enum { >@@ -56,6 +57,7 @@ struct vhost_vsock { > atomic_t queued_replies; > > u32 guest_cid; >+ bool seqpacket_allow; > }; > > static u32 vhost_transport_get_local_cid(void) >@@ -112,6 +114,7 @@ vhost_transport_do_send_pkt(struct vhost_vsock *vsock, > size_t nbytes; > size_t iov_len, payload_len; > int head; >+ bool restore_flag = false; > > spin_lock_bh(&vsock->send_pkt_list_lock); > if (list_empty(&vsock->send_pkt_list)) { >@@ -168,9 +171,15 @@ vhost_transport_do_send_pkt(struct vhost_vsock *vsock, > /* If the packet is greater than the space available in the > * buffer, we split it using multiple buffers. > */ >- if (payload_len > iov_len - sizeof(pkt->hdr)) >+ if (payload_len > iov_len - sizeof(pkt->hdr)) { > payload_len = iov_len - sizeof(pkt->hdr); >Please, add a comment here to explain why we need this.>+ if (le32_to_cpu(pkt->hdr.flags) & >VIRTIO_VSOCK_SEQ_EOR) { >+ pkt->hdr.flags &= ~cpu_to_le32(VIRTIO_VSOCK_SEQ_EOR); >+ restore_flag = true; >+ } >+ } >+ > /* Set the correct length in the header */ > pkt->hdr.len = cpu_to_le32(payload_len); > >@@ -181,6 +190,9 @@ vhost_transport_do_send_pkt(struct vhost_vsock >*vsock, > break; > } > >+ if (restore_flag) >+ pkt->hdr.flags |= cpu_to_le32(VIRTIO_VSOCK_SEQ_EOR); >+Maybe we can restore the flag only if we are queueing again the same packet, I mean in the `if (pkt->off < pkt->len) {` branch below. What do you think?> nbytes = copy_to_iter(pkt->buf + pkt->off, payload_len, > &iov_iter); > if (nbytes != payload_len) { >@@ -354,8 +366,7 @@ vhost_vsock_alloc_pkt(struct vhost_virtqueue *vq, > return NULL; > } > >- if (le16_to_cpu(pkt->hdr.type) == VIRTIO_VSOCK_TYPE_STREAM) >- pkt->len = le32_to_cpu(pkt->hdr.len); >+ pkt->len = le32_to_cpu(pkt->hdr.len); > > /* No payload */ > if (!pkt->len) >@@ -398,6 +409,8 @@ static bool vhost_vsock_more_replies(struct >vhost_vsock *vsock) > return val < vq->num; > } > >+static bool vhost_transport_seqpacket_allow(u32 remote_cid); >+ > static struct virtio_transport vhost_transport = { > .transport = { > .module = THIS_MODULE, >@@ -424,6 +437,10 @@ static struct virtio_transport vhost_transport = { > .stream_is_active = virtio_transport_stream_is_active, > .stream_allow = virtio_transport_stream_allow, > >+ .seqpacket_dequeue = virtio_transport_seqpacket_dequeue, >+ .seqpacket_enqueue = virtio_transport_seqpacket_enqueue, >+ .seqpacket_allow = vhost_transport_seqpacket_allow, >+ > .notify_poll_in = virtio_transport_notify_poll_in, > .notify_poll_out = virtio_transport_notify_poll_out, > .notify_recv_init = virtio_transport_notify_recv_init, >@@ -441,6 +458,22 @@ static struct virtio_transport vhost_transport = { > .send_pkt = vhost_transport_send_pkt, > }; > >+static bool vhost_transport_seqpacket_allow(u32 remote_cid) >+{ >+ struct vhost_vsock *vsock; >+ bool seqpacket_allow = false; >+ >+ rcu_read_lock(); >+ vsock = vhost_vsock_get(remote_cid); >+ >+ if (vsock) >+ seqpacket_allow = vsock->seqpacket_allow; >+ >+ rcu_read_unlock(); >+ >+ return seqpacket_allow; >+} >+ > static void vhost_vsock_handle_tx_kick(struct vhost_work *work) > { > struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, >@@ -785,6 +818,9 @@ static int vhost_vsock_set_features(struct vhost_vsock *vsock, u64 features) > goto err; > } > >+ if (features & (1ULL << VIRTIO_VSOCK_F_SEQPACKET)) >+ vsock->seqpacket_allow = true; >+ > for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) { > vq = &vsock->vqs[i]; > mutex_lock(&vq->mutex); >-- >2.25.1 >