[PATCH 4/4] getport: recognize "vsock" netid

[Stefan Hajnoczi <stefanha@redhat.com>]

Neither libtirpc nor getprotobyname(3) know about AF_VSOCK.  For similar
reasons as for "rdma"/"rmda6", translate "vsock" manually in getport.c.

It is now possible to mount a file system from the host (hypervisor)
over AF_VSOCK like this:

  (guest)$ mount.nfs 2:/export /mnt -v -o clientaddr=3,proto=vsock

The VM's cid address is 3 and the hypervisor is 2.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 support/nfs/getport.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/support/nfs/getport.c b/support/nfs/getport.c
index 081594c..0b857af 100644
--- a/support/nfs/getport.c
+++ b/support/nfs/getport.c
@@ -217,8 +217,7 @@ nfs_get_proto(const char *netid, sa_family_t *family, unsigned long *protocol)
 	struct protoent *proto;
 
 	/*
-	 * IANA does not define a protocol number for rdma netids,
-	 * since "rdma" is not an IP protocol.
+	 * IANA does not define protocol numbers for non-IP netids.
 	 */
 	if (strcmp(netid, "rdma") == 0) {
 		*family = AF_INET;
@@ -230,6 +229,11 @@ nfs_get_proto(const char *netid, sa_family_t *family, unsigned long *protocol)
 		*protocol = NFSPROTO_RDMA;
 		return 1;
 	}
+	if (strcmp(netid, "vsock") == 0) {
+		*family = AF_VSOCK;
+		*protocol = 0;
+		return 1;
+	}
 
 	nconf = getnetconfigent(netid);
 	if (nconf == NULL)
@@ -258,14 +262,18 @@ nfs_get_proto(const char *netid, sa_family_t *family, unsigned long *protocol)
 	struct protoent *proto;
 
 	/*
-	 * IANA does not define a protocol number for rdma netids,
-	 * since "rdma" is not an IP protocol.
+	 * IANA does not define protocol numbers for non-IP netids.
 	 */
 	if (strcmp(netid, "rdma") == 0) {
 		*family = AF_INET;
 		*protocol = NFSPROTO_RDMA;
 		return 1;
 	}
+	if (strcmp(netid, "vsock") == 0) {
+		*family = AF_VSOCK;
+		*protocol = 0;
+		return 1;
+	}
 
 	proto = getprotobyname(netid);
 	if (proto == NULL)
-- 
2.7.4