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Diffstat (limited to 'hw/net/virtio-net.c')
-rw-r--r--hw/net/virtio-net.c68
1 files changed, 66 insertions, 2 deletions
diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index de696e8dd0..5798f87d8e 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -129,6 +129,13 @@ static void virtio_net_vhost_status(VirtIONet *n, uint8_t status)
if (!n->vhost_started) {
int r, i;
+ if (n->needs_vnet_hdr_swap) {
+ error_report("backend does not support %s vnet headers; "
+ "falling back on userspace virtio",
+ virtio_is_big_endian(vdev) ? "BE" : "LE");
+ return;
+ }
+
/* Any packets outstanding? Purge them to avoid touching rings
* when vhost is running.
*/
@@ -153,6 +160,59 @@ static void virtio_net_vhost_status(VirtIONet *n, uint8_t status)
}
}
+static int virtio_net_set_vnet_endian_one(VirtIODevice *vdev,
+ NetClientState *peer,
+ bool enable)
+{
+ if (virtio_is_big_endian(vdev)) {
+ return qemu_set_vnet_be(peer, enable);
+ } else {
+ return qemu_set_vnet_le(peer, enable);
+ }
+}
+
+static bool virtio_net_set_vnet_endian(VirtIODevice *vdev, NetClientState *ncs,
+ int queues, bool enable)
+{
+ int i;
+
+ for (i = 0; i < queues; i++) {
+ if (virtio_net_set_vnet_endian_one(vdev, ncs[i].peer, enable) < 0 &&
+ enable) {
+ while (--i >= 0) {
+ virtio_net_set_vnet_endian_one(vdev, ncs[i].peer, false);
+ }
+
+ return true;
+ }
+ }
+
+ return false;
+}
+
+static void virtio_net_vnet_endian_status(VirtIONet *n, uint8_t status)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(n);
+ int queues = n->multiqueue ? n->max_queues : 1;
+
+ if (virtio_net_started(n, status)) {
+ /* Before using the device, we tell the network backend about the
+ * endianness to use when parsing vnet headers. If the backend
+ * can't do it, we fallback onto fixing the headers in the core
+ * virtio-net code.
+ */
+ n->needs_vnet_hdr_swap = virtio_net_set_vnet_endian(vdev, n->nic->ncs,
+ queues, true);
+ } else if (virtio_net_started(n, vdev->status)) {
+ /* After using the device, we need to reset the network backend to
+ * the default (guest native endianness), otherwise the guest may
+ * lose network connectivity if it is rebooted into a different
+ * endianness.
+ */
+ virtio_net_set_vnet_endian(vdev, n->nic->ncs, queues, false);
+ }
+}
+
static void virtio_net_set_status(struct VirtIODevice *vdev, uint8_t status)
{
VirtIONet *n = VIRTIO_NET(vdev);
@@ -160,6 +220,7 @@ static void virtio_net_set_status(struct VirtIODevice *vdev, uint8_t status)
int i;
uint8_t queue_status;
+ virtio_net_vnet_endian_status(n, status);
virtio_net_vhost_status(n, status);
for (i = 0; i < n->max_queues; i++) {
@@ -963,7 +1024,10 @@ static void receive_header(VirtIONet *n, const struct iovec *iov, int iov_cnt,
void *wbuf = (void *)buf;
work_around_broken_dhclient(wbuf, wbuf + n->host_hdr_len,
size - n->host_hdr_len);
- virtio_net_hdr_swap(VIRTIO_DEVICE(n), wbuf);
+
+ if (n->needs_vnet_hdr_swap) {
+ virtio_net_hdr_swap(VIRTIO_DEVICE(n), wbuf);
+ }
iov_from_buf(iov, iov_cnt, 0, buf, sizeof(struct virtio_net_hdr));
} else {
struct virtio_net_hdr hdr = {
@@ -1184,7 +1248,7 @@ static int32_t virtio_net_flush_tx(VirtIONetQueue *q)
error_report("virtio-net header incorrect");
exit(1);
}
- if (virtio_needs_swap(vdev)) {
+ if (n->needs_vnet_hdr_swap) {
virtio_net_hdr_swap(vdev, (void *) &mhdr);
sg2[0].iov_base = &mhdr;
sg2[0].iov_len = n->guest_hdr_len;