diff options
Diffstat (limited to 'drivers/vhost/net.c')
-rw-r--r-- | drivers/vhost/net.c | 83 |
1 files changed, 23 insertions, 60 deletions
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 9484d5652ca5..8dccca9013ed 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -84,10 +84,6 @@ struct vhost_net_ubuf_ref { struct vhost_net_virtqueue { struct vhost_virtqueue vq; - /* hdr is used to store the virtio header. - * Since each iovec has >= 1 byte length, we never need more than - * header length entries to store the header. */ - struct iovec hdr[sizeof(struct virtio_net_hdr_mrg_rxbuf)]; size_t vhost_hlen; size_t sock_hlen; /* vhost zerocopy support fields below: */ @@ -235,44 +231,6 @@ static bool vhost_sock_zcopy(struct socket *sock) sock_flag(sock->sk, SOCK_ZEROCOPY); } -/* Pop first len bytes from iovec. Return number of segments used. */ -static int move_iovec_hdr(struct iovec *from, struct iovec *to, - size_t len, int iov_count) -{ - int seg = 0; - size_t size; - - while (len && seg < iov_count) { - size = min(from->iov_len, len); - to->iov_base = from->iov_base; - to->iov_len = size; - from->iov_len -= size; - from->iov_base += size; - len -= size; - ++from; - ++to; - ++seg; - } - return seg; -} -/* Copy iovec entries for len bytes from iovec. */ -static void copy_iovec_hdr(const struct iovec *from, struct iovec *to, - size_t len, int iovcount) -{ - int seg = 0; - size_t size; - - while (len && seg < iovcount) { - size = min(from->iov_len, len); - to->iov_base = from->iov_base; - to->iov_len = size; - len -= size; - ++from; - ++to; - ++seg; - } -} - /* In case of DMA done not in order in lower device driver for some reason. * upend_idx is used to track end of used idx, done_idx is used to track head * of used idx. Once lower device DMA done contiguously, we will signal KVM @@ -336,7 +294,7 @@ static void handle_tx(struct vhost_net *net) { struct vhost_net_virtqueue *nvq = &net->vqs[VHOST_NET_VQ_TX]; struct vhost_virtqueue *vq = &nvq->vq; - unsigned out, in, s; + unsigned out, in; int head; struct msghdr msg = { .msg_name = NULL, @@ -395,16 +353,17 @@ static void handle_tx(struct vhost_net *net) break; } /* Skip header. TODO: support TSO. */ - s = move_iovec_hdr(vq->iov, nvq->hdr, hdr_size, out); len = iov_length(vq->iov, out); iov_iter_init(&msg.msg_iter, WRITE, vq->iov, out, len); + iov_iter_advance(&msg.msg_iter, hdr_size); /* Sanity check */ - if (!len) { + if (!iov_iter_count(&msg.msg_iter)) { vq_err(vq, "Unexpected header len for TX: " "%zd expected %zd\n", - iov_length(nvq->hdr, s), hdr_size); + len, hdr_size); break; } + len = iov_iter_count(&msg.msg_iter); zcopy_used = zcopy && len >= VHOST_GOODCOPY_LEN && (nvq->upend_idx + 1) % UIO_MAXIOV != @@ -469,7 +428,7 @@ static int peek_head_len(struct sock *sk) head = skb_peek(&sk->sk_receive_queue); if (likely(head)) { len = head->len; - if (vlan_tx_tag_present(head)) + if (skb_vlan_tag_present(head)) len += VLAN_HLEN; } @@ -579,6 +538,7 @@ static void handle_rx(struct vhost_net *net) size_t vhost_hlen, sock_hlen; size_t vhost_len, sock_len; struct socket *sock; + struct iov_iter fixup; mutex_lock(&vq->mutex); sock = vq->private_data; @@ -623,14 +583,19 @@ static void handle_rx(struct vhost_net *net) break; } /* We don't need to be notified again. */ - if (unlikely((vhost_hlen))) - /* Skip header. TODO: support TSO. */ - move_iovec_hdr(vq->iov, nvq->hdr, vhost_hlen, in); - else - /* Copy the header for use in VIRTIO_NET_F_MRG_RXBUF: - * needed because recvmsg can modify msg_iov. */ - copy_iovec_hdr(vq->iov, nvq->hdr, sock_hlen, in); - iov_iter_init(&msg.msg_iter, READ, vq->iov, in, sock_len); + iov_iter_init(&msg.msg_iter, READ, vq->iov, in, vhost_len); + fixup = msg.msg_iter; + if (unlikely((vhost_hlen))) { + /* We will supply the header ourselves + * TODO: support TSO. + */ + iov_iter_advance(&msg.msg_iter, vhost_hlen); + } else { + /* It'll come from socket; we'll need to patch + * ->num_buffers over if VIRTIO_NET_F_MRG_RXBUF + */ + iov_iter_advance(&fixup, sizeof(hdr)); + } err = sock->ops->recvmsg(NULL, sock, &msg, sock_len, MSG_DONTWAIT | MSG_TRUNC); /* Userspace might have consumed the packet meanwhile: @@ -642,9 +607,9 @@ static void handle_rx(struct vhost_net *net) vhost_discard_vq_desc(vq, headcount); continue; } + /* Supply virtio_net_hdr if VHOST_NET_F_VIRTIO_NET_HDR */ if (unlikely(vhost_hlen) && - memcpy_toiovecend(nvq->hdr, (unsigned char *)&hdr, 0, - vhost_hlen)) { + copy_to_iter(&hdr, sizeof(hdr), &fixup) != sizeof(hdr)) { vq_err(vq, "Unable to write vnet_hdr at addr %p\n", vq->iov->iov_base); break; @@ -653,9 +618,7 @@ static void handle_rx(struct vhost_net *net) hdr.num_buffers = cpu_to_vhost16(vq, headcount); if (likely(mergeable) && - memcpy_toiovecend(nvq->hdr, (void *)&hdr.num_buffers, - offsetof(typeof(hdr), num_buffers), - sizeof hdr.num_buffers)) { + copy_to_iter(&hdr.num_buffers, 2, &fixup) != 2) { vq_err(vq, "Failed num_buffers write"); vhost_discard_vq_desc(vq, headcount); break; |