[libvirt] [PATCH 1/9] util: new function virNetDevMacVLanIsMacvtap()
This function returns T if the given name is a macvtap device. This is
determined by 1) getting the ifindex of the device with that name (if
there is one), and 2) checking for existence of /dev/tapXX, where "XX"
is the ifindex learned in (1).
It's also possible to learn this by getting a netlink dump of the
interface and parsing through it to look for some attributes, but that
is complicated to figure out, takes longer to execute, and I'm lazy.
Signed-off-by: Laine Stump <laine(a)redhat.com>
---
src/libvirt_private.syms | 3 +++
src/util/virnetdevmacvlan.c | 23 +++++++++++++++++++++++
src/util/virnetdevmacvlan.h | 3 +++
3 files changed, 29 insertions(+)
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index a34d92f5ef..afea00b629 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -2523,10 +2523,13 @@ virNetDevMacVLanCreate;
virNetDevMacVLanCreateWithVPortProfile;
virNetDevMacVLanDelete;
virNetDevMacVLanDeleteWithVPortProfile;
+virNetDevMacVLanIsMacvtap;
virNetDevMacVLanModeTypeFromString;
virNetDevMacVLanReleaseName;
virNetDevMacVLanReserveName;
virNetDevMacVLanRestartWithVPortProfile;
+virNetDevMacVLanTapOpen;
+virNetDevMacVLanTapSetup;
virNetDevMacVLanVPortProfileRegisterCallback;
diff --git a/src/util/virnetdevmacvlan.c b/src/util/virnetdevmacvlan.c
index 3302522289..79aa7ed5ac 100644
--- a/src/util/virnetdevmacvlan.c
+++ b/src/util/virnetdevmacvlan.c
@@ -278,6 +278,29 @@ virNetDevMacVLanReleaseName(const char *name)
}
+/**
+ * virNetDevMacVLanIsMacvtap:
+ * @ifname: Name of the interface
+ *
+ * Return T if the named netdev exists and is a macvtap device
+ * F in all other cases.
+ */
+bool
+virNetDevMacVLanIsMacvtap(const char *ifname)
+{
+ int ifindex;
+ VIR_AUTOFREE(char *) tapname = NULL;
+
+ if (virNetDevGetIndex(ifname, &ifindex) < 0)
+ return false;
+
+ if (virAsprintf(&tapname, "/dev/tap%d", ifindex) < 0)
+ return false;
+
+ return virFileExists(tapname);
+}
+
+
/**
* virNetDevMacVLanCreate:
*
diff --git a/src/util/virnetdevmacvlan.h b/src/util/virnetdevmacvlan.h
index d1b479ed9f..8ac7643e49 100644
--- a/src/util/virnetdevmacvlan.h
+++ b/src/util/virnetdevmacvlan.h
@@ -57,6 +57,9 @@ typedef enum {
int virNetDevMacVLanReserveName(const char *name, bool quietfail);
int virNetDevMacVLanReleaseName(const char *name);
+bool virNetDevMacVLanIsMacvtap(const char *ifname)
+ ATTRIBUTE_NONNULL(1) ATTRIBUTE_RETURN_CHECK ATTRIBUTE_NOINLINE;
+
int virNetDevMacVLanCreate(const char *ifname,
const char *type,
const virMacAddr *macaddress,
--
2.21.0