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Diffstat (limited to 'Documentation/lguest/lguest.c')
-rw-r--r--Documentation/lguest/lguest.c31
1 files changed, 9 insertions, 22 deletions
diff --git a/Documentation/lguest/lguest.c b/Documentation/lguest/lguest.c
index b88b0ea54e90..7228369d1014 100644
--- a/Documentation/lguest/lguest.c
+++ b/Documentation/lguest/lguest.c
@@ -895,6 +895,9 @@ static void handle_console_output(int fd, struct virtqueue *vq, bool timeout)
}
}
+/* This is called when we no longer want to hear about Guest changes to a
+ * virtqueue. This is more efficient in high-traffic cases, but it means we
+ * have to set a timer to check if any more changes have occurred. */
static void block_vq(struct virtqueue *vq)
{
struct itimerval itm;
@@ -939,6 +942,11 @@ static void handle_net_output(int fd, struct virtqueue *vq, bool timeout)
if (!timeout && num)
block_vq(vq);
+ /* We never quite know how long should we wait before we check the
+ * queue again for more packets. We start at 500 microseconds, and if
+ * we get fewer packets than last time, we assume we made the timeout
+ * too small and increase it by 10 microseconds. Otherwise, we drop it
+ * by one microsecond every time. It seems to work well enough. */
if (timeout) {
if (num < last_timeout_num)
timeout_usec += 10;
@@ -1447,21 +1455,6 @@ static void configure_device(int fd, const char *tapif, u32 ipaddr)
err(1, "Bringing interface %s up", tapif);
}
-static void get_mac(int fd, const char *tapif, unsigned char hwaddr[6])
-{
- struct ifreq ifr;
-
- memset(&ifr, 0, sizeof(ifr));
- strcpy(ifr.ifr_name, tapif);
-
- /* SIOC stands for Socket I/O Control. G means Get (vs S for Set
- * above). IF means Interface, and HWADDR is hardware address.
- * Simple! */
- if (ioctl(fd, SIOCGIFHWADDR, &ifr) != 0)
- err(1, "getting hw address for %s", tapif);
- memcpy(hwaddr, ifr.ifr_hwaddr.sa_data, 6);
-}
-
static int get_tun_device(char tapif[IFNAMSIZ])
{
struct ifreq ifr;
@@ -1531,11 +1524,8 @@ static void setup_tun_net(char *arg)
p = strchr(arg, ':');
if (p) {
str2mac(p+1, conf.mac);
+ add_feature(dev, VIRTIO_NET_F_MAC);
*p = '\0';
- } else {
- p = arg + strlen(arg);
- /* None supplied; query the randomly assigned mac. */
- get_mac(ipfd, tapif, conf.mac);
}
/* arg is now either an IP address or a bridge name */
@@ -1547,13 +1537,10 @@ static void setup_tun_net(char *arg)
/* Set up the tun device. */
configure_device(ipfd, tapif, ip);
- /* Tell Guest what MAC address to use. */
- add_feature(dev, VIRTIO_NET_F_MAC);
add_feature(dev, VIRTIO_F_NOTIFY_ON_EMPTY);
/* Expect Guest to handle everything except UFO */
add_feature(dev, VIRTIO_NET_F_CSUM);
add_feature(dev, VIRTIO_NET_F_GUEST_CSUM);
- add_feature(dev, VIRTIO_NET_F_MAC);
add_feature(dev, VIRTIO_NET_F_GUEST_TSO4);
add_feature(dev, VIRTIO_NET_F_GUEST_TSO6);
add_feature(dev, VIRTIO_NET_F_GUEST_ECN);