From a2a91a137ad4e9c538c9b63b2bfcf7a105924143 Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Fri, 20 Jul 2018 08:15:16 +0800 Subject: [PATCH] vhost_net: introduce get_tx_bufs() Factor out logic of getting tx buffer and iov iter initialization. This will be used for reducing codes duplication in the future. Signed-off-by: Jason Wang Signed-off-by: David S. Miller --- drivers/vhost/net.c | 49 +++++++++++++++++++++++++++++---------------- 1 file changed, 32 insertions(+), 17 deletions(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index b9e1674ca9e1..a014ca042390 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -484,6 +484,36 @@ static bool vhost_exceeds_weight(int pkts, int total_len) pkts >= VHOST_NET_PKT_WEIGHT; } +static int get_tx_bufs(struct vhost_net *net, + struct vhost_net_virtqueue *nvq, + struct msghdr *msg, + unsigned int *out, unsigned int *in, + size_t *len, bool *busyloop_intr) +{ + struct vhost_virtqueue *vq = &nvq->vq; + int ret; + + ret = vhost_net_tx_get_vq_desc(net, vq, out, in, busyloop_intr); + if (ret < 0 || ret == vq->num) + return ret; + + if (*in) { + vq_err(vq, "Unexpected descriptor format for TX: out %d, int %d\n", + *out, *in); + return -EFAULT; + } + + /* Sanity check */ + *len = init_iov_iter(vq, &msg->msg_iter, nvq->vhost_hlen, *out); + if (*len == 0) { + vq_err(vq, "Unexpected header len for TX: %zd expected %zd\n", + *len, nvq->vhost_hlen); + return -EFAULT; + } + + return ret; +} + /* Expects to be always run from workqueue - which acts as * read-size critical section for our kind of RCU. */ static void handle_tx(struct vhost_net *net) @@ -501,7 +531,6 @@ static void handle_tx(struct vhost_net *net) }; size_t len, total_len = 0; int err; - size_t hdr_size; struct socket *sock; struct vhost_net_ubuf_ref *uninitialized_var(ubufs); bool zcopy, zcopy_used; @@ -518,7 +547,6 @@ static void handle_tx(struct vhost_net *net) vhost_disable_notify(&net->dev, vq); vhost_net_disable_vq(net, vq); - hdr_size = nvq->vhost_hlen; zcopy = nvq->ubufs; for (;;) { @@ -529,8 +557,8 @@ static void handle_tx(struct vhost_net *net) vhost_zerocopy_signal_used(net, vq); busyloop_intr = false; - head = vhost_net_tx_get_vq_desc(net, vq, &out, &in, - &busyloop_intr); + head = get_tx_bufs(net, nvq, &msg, &out, &in, &len, + &busyloop_intr); /* On error, stop handling until the next kick. */ if (unlikely(head < 0)) break; @@ -544,19 +572,6 @@ static void handle_tx(struct vhost_net *net) } break; } - if (in) { - vq_err(vq, "Unexpected descriptor format for TX: " - "out %d, int %d\n", out, in); - break; - } - - /* Sanity check */ - len = init_iov_iter(vq, &msg.msg_iter, hdr_size, out); - if (!len) { - vq_err(vq, "Unexpected header len for TX: %zd expected %zd\n", - len, hdr_size); - break; - } zcopy_used = zcopy && len >= VHOST_GOODCOPY_LEN && !vhost_exceeds_maxpend(net) -- 2.30.2