umount.nfs command: Add an AF_INET6-capable version of nfs_call_unmount()

We need an AF_INET6-capable version of nfs_call_unmount() to allow the
umount.nfs command to support unmounting NFS servers over IPv6.  The
legacy
mount.nfs command still likes to use nfs_call_umount(), so we leave it
in
place and introduce a new API that can take a "struct sockaddr *".

The umount.nfs command will invoke this new API, but we'll leave the
legacy
mount.nfs command and the umount.nfs4 command alone.  The umount.nfs4
command does not need this support because NFSv4 unmount operations are
entirely local.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Steve Dickson <steved@redhat.com>

1 files changed, 53 insertions, 0 deletions

diff --git a/utils/mount/network.c b/utils/mount/network.c
index a974953..92f75b4 100644
--- a/utils/mount/network.c
+++ b/utils/mount/network.c
@@ -838,6 +838,59 @@ int start_statd(void)
 }
 
 /**
+ * nfs_advise_umount - ask the server to remove a share from it's rmtab
+ * @sap: pointer to IP address of server to call
+ * @salen: length of server address
+ * @pmap: partially filled-in mountd RPC service tuple
+ * @argp: directory path of share to "unmount"
+ *
+ * Returns one if the unmount call succeeded; zero if the unmount
+ * failed for any reason;  rpccreateerr.cf_stat is set to reflect
+ * the nature of the error.
+ *
+ * We use a fast timeout since this call is advisory only.
+ */
+int nfs_advise_umount(const struct sockaddr *sap, const socklen_t salen,
+		      const struct pmap *pmap, const dirpath *argp)
+{
+	struct sockaddr_storage address;
+	struct sockaddr *saddr = (struct sockaddr *)&address;
+	struct pmap mnt_pmap = *pmap;
+	struct timeval timeout = {
+		.tv_sec		= MOUNT_TIMEOUT >> 3,
+	};
+	CLIENT *client;
+	enum clnt_stat res = 0;
+
+	if (nfs_probe_mntport(sap, salen, &mnt_pmap) == 0)
+		return 0;
+
+	memcpy(saddr, sap, salen);
+	nfs_set_port(saddr, mnt_pmap.pm_port);
+
+	client = nfs_get_rpcclient(saddr, salen, mnt_pmap.pm_prot,
+					mnt_pmap.pm_prog, mnt_pmap.pm_vers,
+					&timeout);
+	if (client == NULL)
+		return 0;
+
+	client->cl_auth = authunix_create_default();
+
+	res = CLNT_CALL(client, MOUNTPROC_UMNT,
+			(xdrproc_t)xdr_dirpath, (caddr_t)argp,
+			(xdrproc_t)xdr_void, NULL,
+			timeout);
+
+	auth_destroy(client->cl_auth);
+	CLNT_DESTROY(client);
+
+	if (res != RPC_SUCCESS)
+		return 0;
+
+	return 1;
+}
+
+/**
  * nfs_call_umount - ask the server to remove a share from it's rmtab
  * @mnt_server: address of RPC MNT program server
  * @argp: directory path of share to "unmount"