diff options
| -rw-r--r-- | net/tap-bsd.c | 38 |
1 files changed, 33 insertions, 5 deletions
diff --git a/net/tap-bsd.c b/net/tap-bsd.c index 7028d9be95..0103a97bf6 100644 --- a/net/tap-bsd.c +++ b/net/tap-bsd.c @@ -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; |