tap-bsd: use user-specified tap device if it already exists

Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Ed Maste <emaste@freebsd.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
This commit is contained in:
Ed Maste 2015-10-23 11:53:55 -04:00 committed by Michael Tokarev
parent a2f31f1804
commit bd54a9f943

View File

@ -109,8 +109,7 @@ int tap_open(char *ifname, int ifname_size, int *vnet_hdr,
#define PATH_NET_TAP "/dev/tap"
int tap_open(char *ifname, int ifname_size, int *vnet_hdr,
int vnet_hdr_required, int mq_required, Error **errp)
static int tap_open_clone(char *ifname, int ifname_size, Error **errp)
{
int fd, s, ret;
struct ifreq ifr;
@ -126,7 +125,8 @@ int tap_open(char *ifname, int ifname_size, int *vnet_hdr,
ret = ioctl(fd, TAPGIFNAME, (void *)&ifr);
if (ret < 0) {
error_setg_errno(errp, errno, "could not get tap interface name");
goto error;
close(fd);
return -1;
}
if (ifname[0] != '\0') {
@ -135,19 +135,47 @@ int tap_open(char *ifname, int ifname_size, int *vnet_hdr,
if (s < 0) {
error_setg_errno(errp, errno,
"could not open socket to set interface name");
goto error;
close(fd);
return -1;
}
ifr.ifr_data = ifname;
ret = ioctl(s, SIOCSIFNAME, (void *)&ifr);
close(s);
if (ret < 0) {
error_setg(errp, "could not set tap interface name");
goto error;
close(fd);
return -1;
}
} else {
pstrcpy(ifname, ifname_size, ifr.ifr_name);
}
return fd;
}
int tap_open(char *ifname, int ifname_size, int *vnet_hdr,
int vnet_hdr_required, int mq_required, Error **errp)
{
int fd = -1;
/* If the specified tap device already exists just use it. */
if (ifname[0] != '\0') {
char dname[100];
snprintf(dname, sizeof dname, "/dev/%s", ifname);
TFR(fd = open(dname, O_RDWR));
if (fd < 0 && errno != ENOENT) {
error_setg_errno(errp, errno, "could not open %s", dname);
return -1;
}
}
if (fd < 0) {
/* Tap device not specified or does not exist. */
if ((fd = tap_open_clone(ifname, ifname_size, errp)) < 0) {
return -1;
}
}
if (*vnet_hdr) {
/* BSD doesn't have IFF_VNET_HDR */
*vnet_hdr = 0;