[libvirt] [PATCH 1/4] util: netlink function to delete any network device
libvirt has always used the netlink RTM_DELLINK message to delete
macvtap/macvlan devices, but it can actually be used to delete other
types of network devices, such as bonds and bridges. This patch makes
virNetDevMacVLanDelete() available as a generic function so it can
intelligibly be called to delete these other types of interfaces.
---
src/libvirt_private.syms | 1 +
src/util/virnetlink.c | 89 ++++++++++++++++++++++++++++++++++++++++++++++++
src/util/virnetlink.h | 3 +-
3 files changed, 92 insertions(+), 1 deletion(-)
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index ca3520d..631edf3 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -1805,6 +1805,7 @@ virNetDevVPortProfileOpTypeToString;
# util/virnetlink.h
virNetlinkCommand;
+virNetlinkDelLink;
virNetlinkEventAddClient;
virNetlinkEventRemoveClient;
virNetlinkEventServiceIsRunning;
diff --git a/src/util/virnetlink.c b/src/util/virnetlink.c
index d52f66a..86c9c9c 100644
--- a/src/util/virnetlink.c
+++ b/src/util/virnetlink.c
@@ -277,6 +277,87 @@ int virNetlinkCommand(struct nl_msg *nl_msg,
}
+/**
+ * virNetlinkDelLink:
+ *
+ * @ifname: Name of the link
+ *
+ * delete a network "link" (aka interface aka device) with the given
+ * name. This works for many different types of network devices,
+ * including macvtap and bridges.
+ *
+ * Returns 0 on success, -1 on fatal error.
+ */
+int
+virNetlinkDelLink(const char *ifname)
+{
+ int rc = -1;
+ struct nlmsghdr *resp = NULL;
+ struct nlmsgerr *err;
+ struct ifinfomsg ifinfo = { .ifi_family = AF_UNSPEC };
+ unsigned int recvbuflen;
+ struct nl_msg *nl_msg;
+
+ nl_msg = nlmsg_alloc_simple(RTM_DELLINK,
+ NLM_F_REQUEST | NLM_F_CREATE | NLM_F_EXCL);
+ if (!nl_msg) {
+ virReportOOMError();
+ return -1;
+ }
+
+ if (nlmsg_append(nl_msg, &ifinfo, sizeof(ifinfo), NLMSG_ALIGNTO) < 0)
+ goto buffer_too_small;
+
+ if (nla_put(nl_msg, IFLA_IFNAME, strlen(ifname)+1, ifname) < 0)
+ goto buffer_too_small;
+
+ if (virNetlinkCommand(nl_msg, &resp, &recvbuflen, 0, 0,
+ NETLINK_ROUTE, 0) < 0) {
+ goto cleanup;
+ }
+
+ if (recvbuflen < NLMSG_LENGTH(0) || resp == NULL)
+ goto malformed_resp;
+
+ switch (resp->nlmsg_type) {
+ case NLMSG_ERROR:
+ err = (struct nlmsgerr *)NLMSG_DATA(resp);
+ if (resp->nlmsg_len < NLMSG_LENGTH(sizeof(*err)))
+ goto malformed_resp;
+
+ if (err->error) {
+ virReportSystemError(-err->error,
+ _("error destroying network device %s"),
+ ifname);
+ goto cleanup;
+ }
+ break;
+
+ case NLMSG_DONE:
+ break;
+
+ default:
+ goto malformed_resp;
+ }
+
+ rc = 0;
+ cleanup:
+ nlmsg_free(nl_msg);
+ VIR_FREE(resp);
+ return rc;
+
+ malformed_resp:
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("malformed netlink response message"));
+ goto cleanup;
+
+ buffer_too_small:
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("allocated netlink buffer is too small"));
+ goto cleanup;
+}
+
+
int
virNetlinkGetErrorCode(struct nlmsghdr *resp, unsigned int recvbuflen)
{
@@ -803,6 +884,14 @@ int virNetlinkCommand(struct nl_msg *nl_msg ATTRIBUTE_UNUSED,
return -1;
}
+
+int
+virNetlinkDelLink(const char *ifname ATTRIBUTE_UNSUPPORTED)
+{
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _(unsupported));
+ return -1;
+}
+
/**
* stopNetlinkEventServer: stop the monitor to receive netlink
* messages for libvirtd
diff --git a/src/util/virnetlink.h b/src/util/virnetlink.h
index 1a3e06d..06c3cd0 100644
--- a/src/util/virnetlink.h
+++ b/src/util/virnetlink.h
@@ -1,5 +1,5 @@
/*
- * Copyright (C) 2010-2013 Red Hat, Inc.
+ * Copyright (C) 2010-2013, 2015 Red Hat, Inc.
* Copyright (C) 2010-2012 IBM Corporation
*
* This library is free software; you can redistribute it and/or
@@ -51,6 +51,7 @@ int virNetlinkCommand(struct nl_msg *nl_msg,
struct nlmsghdr **resp, unsigned int *respbuflen,
uint32_t src_pid, uint32_t dst_pid,
unsigned int protocol, unsigned int groups);
+int virNetlinkDelLink(const char *ifname);
int virNetlinkGetErrorCode(struct nlmsghdr *resp, unsigned int recvbuflen);
--
2.1.0