mount nfs volumes when specified

Use external mount.nfs binary (nfs-utils-1-3-4, 188354e57) to
avoid adding too much complexity (viz, rpc mnt protocol support).

Signed-off-by: Peng Tao <bergwolf@gmail.com>

Author: bergwolf

build/make-initrd.sh

@@ -15,6 +15,7 @@ cp ../src/init /tmp/hyperstart-rootfs
 cp busybox /tmp/hyperstart-rootfs
 cp iptables /tmp/hyperstart-rootfs
 cp libm.so.6 /tmp/hyperstart-rootfs/lib64/
+cp mount.nfs /tmp/hyperstart-rootfs/sbin/mount.nfs4
 
 if [ "$1"x = "aarch64"x ]; then
 	echo "build hyperstart for aarch64"

build/mount.nfs

@@ -113,23 +113,33 @@ static int container_setup_volume(struct hyper_container *container)
 		sprintf(path, "/tmp/%s", vol->mountpoint);
 		sprintf(mountpoint, "./%s", vol->mountpoint);
 
-		fprintf(stdout, "mount %s to %s, tmp path %s\n",
-			dev, vol->mountpoint, path);
-
 		if (hyper_mkdir(path, 0755) < 0) {
 			perror("create volume dir failed");
 			return -1;
 		}
 
-		if (!strncmp(vol->fstype, "xfs", strlen("xfs")))
-			options = "nouuid";
+		if (!strcmp(vol->fstype, "nfs")) {
+			fprintf(stdout, "mount nfs share %s to %s, tmp path %s\n",
+				vol->device, vol->mountpoint, path);
 
-		if (mount(dev, path, vol->fstype, 0, options) < 0) {
-			perror("mount volume device failed");
-			return -1;
+			if (hyper_mount_nfs(vol->device, path) < 0)
+				return -1;
+			/* nfs export has implicitly included _data part of the volume */
+			sprintf(volume, "/%s/", path);
+		} else {
+			fprintf(stdout, "mount %s to %s, tmp path %s\n",
+				dev, vol->mountpoint, path);
+
+			if (!strcmp(vol->fstype, "xfs"))
+				options = "nouuid";
+
+			if (mount(dev, path, vol->fstype, 0, options) < 0) {
+				perror("mount volume device failed");
+				return -1;
+			}
+			sprintf(volume, "/%s/_data", path);
 		}
 
-		sprintf(volume, "/%s/_data", path);
 		if (container_check_file_volume(volume, &filevolume) < 0)
 			return -1;
 

src/container.c

@@ -703,3 +703,11 @@ ssize_t nonblock_read(int fd, void *buf, size_t count)
 
 	return len > 0 ? len : ret;
 }
+
+int hyper_mount_nfs(char *server, char *mountpoint)
+{
+	char cmd[512];
+	snprintf(cmd, sizeof(cmd), "mount.nfs4 -n %s %s", server, mountpoint);
+
+	return hyper_cmd(cmd);
+}

src/util.c

@@ -40,4 +40,5 @@ struct passwd *hyper_getpwnam(const char *name);
 struct group *hyper_getgrnam(const char *name);
 int hyper_getgrouplist(const char *user, gid_t group, gid_t *groups, int *ngroups);
 ssize_t nonblock_read(int fd, void *buf, size_t count);
+int hyper_mount_nfs(char *server, char *mountpoint);
 #endif