Extend r226676 to allow rename without unmount even for file systems with

non-legacy mountpoints. It is better to be able to rename such file systems and
let them be mounted in old places until next reboot than using live CD, etc. to
rename with remount.

This is implemented by adding -u option to 'zfs rename'. If file system's
mountpoint property is set to 'legacy' or 'none', there is no need to specify -u.

Update zfs(8) manual page to reflect this addition.

MFC after:	2 weeks

1 files changed, 27 insertions, 11 deletions

diff --git a/cddl/contrib/opensolaris/cmd/zfs/zfs_main.c b/cddl/contrib/opensolaris/cmd/zfs/zfs_main.c
index bc5a662..1f51bc2 100644
--- a/cddl/contrib/opensolaris/cmd/zfs/zfs_main.c
+++ b/cddl/contrib/opensolaris/cmd/zfs/zfs_main.c
@@ -253,7 +253,8 @@ get_usage(zfs_help_t idx)
 		return (gettext("\trename <filesystem|volume|snapshot> "
 		    "<filesystem|volume|snapshot>\n"
 		    "\trename -p <filesystem|volume> <filesystem|volume>\n"
-		    "\trename -r <snapshot> <snapshot>"));
+		    "\trename -r <snapshot> <snapshot>\n"
+		    "\trename -u [-p] <filesystem> <filesystem>"));
 	case HELP_ROLLBACK:
 		return (gettext("\trollback [-rRf] <snapshot>\n"));
 	case HELP_SEND:
@@ -2851,6 +2852,7 @@ zfs_do_list(int argc, char **argv)
  * zfs rename <fs | snap | vol> <fs | snap | vol>
  * zfs rename -p <fs | vol> <fs | vol>
  * zfs rename -r <snap> <snap>
+ * zfs rename -u [-p] <fs> <fs>
  *
  * Renames the given dataset to another of the same type.
  *
@@ -2861,19 +2863,21 @@ static int
 zfs_do_rename(int argc, char **argv)
 {
 	zfs_handle_t *zhp;
-	int c;
-	int ret;
-	boolean_t recurse = B_FALSE;
+	renameflags_t flags = { 0 };
+	int c, ret, types;
 	boolean_t parents = B_FALSE;
 
 	/* check options */
-	while ((c = getopt(argc, argv, "pr")) != -1) {
+	while ((c = getopt(argc, argv, "pru")) != -1) {
 		switch (c) {
 		case 'p':
 			parents = B_TRUE;
 			break;
 		case 'r':
-			recurse = B_TRUE;
+			flags.recurse = B_TRUE;
+			break;
+		case 'u':
+			flags.nounmount = B_TRUE;
 			break;
 		case '?':
 		default:
@@ -2902,20 +2906,32 @@ zfs_do_rename(int argc, char **argv)
 		usage(B_FALSE);
 	}
 
-	if (recurse && parents) {
+	if (flags.recurse && parents) {
 		(void) fprintf(stderr, gettext("-p and -r options are mutually "
 		    "exclusive\n"));
 		usage(B_FALSE);
 	}
 
-	if (recurse && strchr(argv[0], '@') == 0) {
+	if (flags.recurse && strchr(argv[0], '@') == 0) {
 		(void) fprintf(stderr, gettext("source dataset for recursive "
 		    "rename must be a snapshot\n"));
 		usage(B_FALSE);
 	}
 
-	if ((zhp = zfs_open(g_zfs, argv[0], parents ? ZFS_TYPE_FILESYSTEM |
-	    ZFS_TYPE_VOLUME : ZFS_TYPE_DATASET)) == NULL)
+	if (flags.nounmount && parents) {
+		(void) fprintf(stderr, gettext("-u and -r options are mutually "
+		    "exclusive\n"));
+		usage(B_FALSE);
+	}
+
+	if (flags.nounmount)
+		types = ZFS_TYPE_FILESYSTEM;
+	else if (parents)
+		types = ZFS_TYPE_FILESYSTEM | ZFS_TYPE_VOLUME;
+	else
+		types = ZFS_TYPE_DATASET;
+
+	if ((zhp = zfs_open(g_zfs, argv[0], types)) == NULL)
 		return (1);
 
 	/* If we were asked and the name looks good, try to create ancestors. */
@@ -2925,7 +2941,7 @@ zfs_do_rename(int argc, char **argv)
 		return (1);
 	}
 
-	ret = (zfs_rename(zhp, argv[1], recurse) != 0);
+	ret = (zfs_rename(zhp, argv[1], flags) != 0);
 
 	zfs_close(zhp);
 	return (ret);