Commit bd54a9f9 authored by Ed Maste's avatar Ed Maste Committed by Michael Tokarev
Browse files

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



Acked-by: default avatarRoger Pau Monné <roger.pau@citrix.com>
Signed-off-by: default avatarEd Maste <emaste@freebsd.org>
Signed-off-by: default avatarMichael Tokarev <mjt@tls.msk.ru>
parent a2f31f18

net/tap-bsd.c

+33 −5
Original line number Diff line number Diff line
@@ -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;