diff options
| -rw-r--r-- | net.c | 42 | ||||
| -rw-r--r-- | qemu-options.hx | 4 |
2 files changed, 35 insertions, 11 deletions
@@ -1494,7 +1494,8 @@ static TAPState *net_tap_fd_init(VLANState *vlan, } #if defined (CONFIG_BSD) || defined (__FreeBSD_kernel__) -static int tap_open(char *ifname, int ifname_size, int *vnet_hdr) +static int tap_open(char *ifname, int ifname_size, + int *vnet_hdr, int vnet_hdr_required) { int fd; char *dev; @@ -1636,7 +1637,8 @@ static int tap_alloc(char *dev, size_t dev_size) return tap_fd; } -static int tap_open(char *ifname, int ifname_size, int *vnet_hdr) +static int tap_open(char *ifname, int ifname_size, + int *vnet_hdr, int vnet_hdr_required) { char dev[10]=""; int fd; @@ -1649,13 +1651,15 @@ static int tap_open(char *ifname, int ifname_size, int *vnet_hdr) return fd; } #elif defined (_AIX) -static int tap_open(char *ifname, int ifname_size, int *vnet_hdr) +static int tap_open(char *ifname, int ifname_size, + int *vnet_hdr, int vnet_hdr_required) { fprintf (stderr, "no tap on AIX\n"); return -1; } #else -static int tap_open(char *ifname, int ifname_size, int *vnet_hdr) +static int tap_open(char *ifname, int ifname_size, + int *vnet_hdr, int vnet_hdr_required) { struct ifreq ifr; int fd, ret; @@ -1668,7 +1672,7 @@ static int tap_open(char *ifname, int ifname_size, int *vnet_hdr) memset(&ifr, 0, sizeof(ifr)); ifr.ifr_flags = IFF_TAP | IFF_NO_PI; - { + if (*vnet_hdr) { unsigned int features; if (ioctl(fd, TUNGETFEATURES, &features) == 0 && @@ -1676,6 +1680,13 @@ static int tap_open(char *ifname, int ifname_size, int *vnet_hdr) *vnet_hdr = 1; ifr.ifr_flags |= IFF_VNET_HDR; } + + if (vnet_hdr_required && !*vnet_hdr) { + qemu_error("vnet_hdr=1 requested, but no kernel " + "support for IFF_VNET_HDR available"); + close(fd); + return -1; + } } if (ifname[0] != '\0') @@ -1740,7 +1751,7 @@ static int launch_script(const char *setup_script, const char *ifname, int fd) static int net_tap_init(QemuOpts *opts, int *vnet_hdr) { - int fd; + int fd, vnet_hdr_required; char ifname[128] = {0,}; const char *setup_script; @@ -1748,8 +1759,14 @@ static int net_tap_init(QemuOpts *opts, int *vnet_hdr) pstrcpy(ifname, sizeof(ifname), qemu_opt_get(opts, "ifname")); } - *vnet_hdr = 0; - TFR(fd = tap_open(ifname, sizeof(ifname), vnet_hdr)); + *vnet_hdr = qemu_opt_get_bool(opts, "vnet_hdr", 1); + if (qemu_opt_get(opts, "vnet_hdr")) { + vnet_hdr_required = *vnet_hdr; + } else { + vnet_hdr_required = 0; + } + + TFR(fd = tap_open(ifname, sizeof(ifname), vnet_hdr, vnet_hdr_required)); if (fd < 0) { return -1; } @@ -2698,8 +2715,9 @@ static int net_init_tap(QemuOpts *opts, if (qemu_opt_get(opts, "fd")) { if (qemu_opt_get(opts, "ifname") || qemu_opt_get(opts, "script") || - qemu_opt_get(opts, "downscript")) { - qemu_error("ifname=, script= and downscript= is invalid with fd=\n"); + qemu_opt_get(opts, "downscript") || + qemu_opt_get(opts, "vnet_hdr")) { + qemu_error("ifname=, script=, downscript= and vnet_hdr= is invalid with fd=\n"); return -1; } @@ -3055,6 +3073,10 @@ static struct { .name = "sndbuf", .type = QEMU_OPT_SIZE, .help = "send buffer limit" + }, { + .name = "vnet_hdr", + .type = QEMU_OPT_BOOL, + .help = "enable the IFF_VNET_HDR flag on the tap interface" }, { /* end of list */ } }, diff --git a/qemu-options.hx b/qemu-options.hx index c745e0c..d78b738 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -810,7 +810,7 @@ DEF("net", HAS_ARG, QEMU_OPTION_net, "-net tap[,vlan=n][,name=str],ifname=name\n" " connect the host TAP network interface to VLAN 'n'\n" #else - "-net tap[,vlan=n][,name=str][,fd=h][,ifname=name][,script=file][,downscript=dfile][,sndbuf=nbytes]\n" + "-net tap[,vlan=n][,name=str][,fd=h][,ifname=name][,script=file][,downscript=dfile][,sndbuf=nbytes][,vnet_hdr=on|off]\n" " connect the host TAP network interface to VLAN 'n' and use the\n" " network scripts 'file' (default=%s)\n" " and 'dfile' (default=%s);\n" @@ -818,6 +818,8 @@ DEF("net", HAS_ARG, QEMU_OPTION_net, " use 'fd=h' to connect to an already opened TAP interface\n" " use 'sndbuf=nbytes' to limit the size of the send buffer; the\n" " default of 'sndbuf=1048576' can be disabled using 'sndbuf=0'\n" + " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag; use\n" + " vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n" #endif "-net socket[,vlan=n][,name=str][,fd=h][,listen=[host]:port][,connect=host:port]\n" " connect the vlan 'n' to another VLAN using a socket connection\n" |
