UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

vhost_net: introduce helper to initialize tx iov iter 

Introduce init_iov_iter() in order to be reused by future patch.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jason Wang 2018-07-20 08:15:14 +08:00 committed by David S. Miller
parent 652e4f3e82
commit b0d0ea50e7
1 changed files with 17 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
drivers/vhost/net.c
View File

@ -466,6 +466,18 @@ static bool vhost_exceeds_maxpend(struct vhost_net *net)
min_t(unsigned int, VHOST_MAX_PEND, vq->num >> 2);
}
static size_t init_iov_iter(struct vhost_virtqueue *vq, struct iov_iter *iter,
size_t hdr_size, int out)
{
/* Skip header. TODO: support TSO. */
size_t len = iov_length(vq->iov, out);
iov_iter_init(iter, WRITE, vq->iov, out, len);
iov_iter_advance(iter, hdr_size);
return iov_iter_count(iter);
}
/* 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)
@ -531,18 +543,14 @@ static void handle_tx(struct vhost_net *net)
"out %d, int %d\n", out, in);
break;
}
/* Skip header. TODO: support TSO. */
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 (!msg_data_left(&msg)) {
vq_err(vq, "Unexpected header len for TX: "
"%zd expected %zd\n",
len, hdr_size);
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;
}
len = msg_data_left(&msg);
zcopy_used = zcopy && len >= VHOST_GOODCOPY_LEN
&& !vhost_exceeds_maxpend(net)