6364129 need to unmount any child datasets before doing the rollback

6364126 cannot rollback when a child filesystem is created after a snapshot is taken
6350233 Cannot rename filesystem|volume while it has dependent clones

5 files changed, 199 insertions, 114 deletions

diff --git a/usr/src/cmd/zfs/zfs_main.c b/usr/src/cmd/zfs/zfs_main.c
index 856cf51526..7a9de1cf95 100644
--- a/usr/src/cmd/zfs/zfs_main.c
+++ b/usr/src/cmd/zfs/zfs_main.c
@@ -1284,7 +1284,6 @@ error:
 typedef struct rollback_cbdata {
 	uint64_t	cb_create;
 	int		cb_first;
-	int		cb_force;
 	int		cb_doclones;
 	char		*cb_target;
 	int		cb_error;
@@ -1308,6 +1307,7 @@ rollback_check(zfs_handle_t *zhp, void *data)
 
 	if (!cbp->cb_dependent) {
 		if (strcmp(zfs_get_name(zhp), cbp->cb_target) != 0 &&
+		    zfs_get_type(zhp) == ZFS_TYPE_SNAPSHOT &&
 		    zfs_prop_get_int(zhp, ZFS_PROP_CREATETXG) >
 		    cbp->cb_create) {
 
@@ -1352,83 +1352,22 @@ rollback_check(zfs_handle_t *zhp, void *data)
 	return (0);
 }
 
-/*
- * Unmount any filesystems or snapshots that will need to be destroyed as part
- * of the rollback process.
- */
-static int
-rollback_unmount(zfs_handle_t *zhp, void *data)
-{
-	rollback_cbdata_t *cbp = data;
-
-	if (!cbp->cb_dependent) {
-		if (strcmp(zfs_get_name(zhp), cbp->cb_target) != 0 &&
-		    zfs_prop_get_int(zhp, ZFS_PROP_CREATETXG) >
-		    cbp->cb_create) {
-
-			cbp->cb_dependent = TRUE;
-			(void) zfs_iter_dependents(zhp, rollback_unmount, cbp);
-			cbp->cb_dependent = FALSE;
-
-			if (zfs_unmount(zhp, NULL,
-			    cbp->cb_force ? MS_FORCE: 0) != 0)
-				cbp->cb_error = 1;
-		}
-	} else if (zfs_unmount(zhp, NULL, cbp->cb_force ? MS_FORCE : 0) != 0) {
-		cbp->cb_error = 1;
-	}
-
-	zfs_close(zhp);
-	return (0);
-}
-
-/*
- * Destroy any more recent snapshots.  We invoke this callback on any dependents
- * of the snapshot first.  If the 'cb_dependent' member is non-zero, then this
- * is a dependent and we should just destroy it without checking the transaction
- * group.
- */
-static int
-rollback_destroy(zfs_handle_t *zhp, void *data)
-{
-	rollback_cbdata_t *cbp = data;
-
-	if (!cbp->cb_dependent) {
-		if (strcmp(zfs_get_name(zhp), cbp->cb_target) != 0 &&
-		    zfs_prop_get_int(zhp, ZFS_PROP_CREATETXG) >
-		    cbp->cb_create) {
-
-			cbp->cb_dependent = TRUE;
-			(void) zfs_iter_dependents(zhp, rollback_destroy, cbp);
-			cbp->cb_dependent = FALSE;
-
-			if (zfs_destroy(zhp) != 0)
-				cbp->cb_error = 1;
-		}
-	} else if (zfs_destroy(zhp) != 0) {
-		cbp->cb_error = 1;
-	}
-
-	zfs_close(zhp);
-	return (0);
-}
-
 static int
 zfs_do_rollback(int argc, char **argv)
 {
 	int ret;
 	int c;
 	rollback_cbdata_t cb = { 0 };
-	int was_mounted;
 	zfs_handle_t *zhp, *snap;
 	char parentname[ZFS_MAXNAMELEN];
 	char *delim;
+	int force = 0;
 
 	/* check options */
 	while ((c = getopt(argc, argv, "rfR")) != -1) {
 		switch (c) {
 		case 'f':
-			cb.cb_force = TRUE;
+			force = 1;
 			break;
 		case 'r':
 			cb.cb_recurse = 1;
@@ -1457,13 +1396,12 @@ zfs_do_rollback(int argc, char **argv)
 		usage(FALSE);
 	}
 
-	cb.cb_target = argv[0];
-
 	/* open the snapshot */
-	if ((snap = zfs_open(cb.cb_target, ZFS_TYPE_SNAPSHOT)) == NULL)
+	if ((snap = zfs_open(argv[0], ZFS_TYPE_SNAPSHOT)) == NULL)
 		return (1);
 
-	(void) strlcpy(parentname, cb.cb_target, sizeof (parentname));
+	/* open the parent dataset */
+	(void) strlcpy(parentname, argv[0], sizeof (parentname));
 	verify((delim = strrchr(parentname, '@')) != NULL);
 	*delim = '\0';
 	if ((zhp = zfs_open(parentname, ZFS_TYPE_ANY)) == NULL) {
@@ -1471,15 +1409,12 @@ zfs_do_rollback(int argc, char **argv)
 		return (1);
 	}
 
-	/* See if this dataset is mounted */
-	was_mounted = zfs_is_mounted(zhp, NULL);
-
-	cb.cb_create = zfs_prop_get_int(snap, ZFS_PROP_CREATETXG);
-
 	/*
 	 * Check for more recent snapshots and/or clones based on the presence
 	 * of '-r' and '-R'.
 	 */
+	cb.cb_target = argv[0];
+	cb.cb_create = zfs_prop_get_int(snap, ZFS_PROP_CREATETXG);
 	cb.cb_first = 1;
 	cb.cb_error = 0;
 	(void) zfs_iter_children(zhp, rollback_check, &cb);
@@ -1487,33 +1422,10 @@ zfs_do_rollback(int argc, char **argv)
 	if ((ret = cb.cb_error) != 0)
 		goto out;
 
-	cb.cb_error = 0;
-
-	/*
-	 * Unmount any snapshots as well as the dataset itself.
-	 */
-	if ((ret = zfs_iter_children(zhp, rollback_unmount,
-	    &cb)) != 0 || (ret = zfs_unmount(zhp, NULL,
-		cb.cb_force ? MS_FORCE : 0)) != 0)
-		goto out;
-
-	(void) zfs_iter_children(zhp, rollback_destroy, &cb);
-
-	if ((ret = cb.cb_error) != 0)
-		goto out;
-
-	/*
-	 * Now that we have verified that the snapshot is the latest, rollback
-	 * to the given snapshot.
-	 */
-	ret = zfs_rollback(zhp);
-
 	/*
-	 * We only want to re-mount the filesystem if it was mounted in the
-	 * first place.
+	 * Rollback parent to the given snapshot.
 	 */
-	if (was_mounted)
-		(void) zfs_mount(zhp, NULL, 0);
+	ret = zfs_rollback(zhp, snap, force);
 
 out:
 	zfs_close(snap);
diff --git a/usr/src/lib/libzfs/common/libzfs.h b/usr/src/lib/libzfs/common/libzfs.h
index 525baa2066..63e394c376 100644
--- a/usr/src/lib/libzfs/common/libzfs.h
+++ b/usr/src/lib/libzfs/common/libzfs.h
@@ -20,7 +20,7 @@
  * CDDL HEADER END
  */
 /*
- * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
+ * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
  */
 
@@ -204,7 +204,7 @@ extern int zfs_create(const char *, zfs_type_t, const char *, const char *);
 extern int zfs_destroy(zfs_handle_t *);
 extern int zfs_clone(zfs_handle_t *, const char *);
 extern int zfs_snapshot(const char *);
-extern int zfs_rollback(zfs_handle_t *);
+extern int zfs_rollback(zfs_handle_t *, zfs_handle_t *, int);
 extern int zfs_rename(zfs_handle_t *, const char *);
 extern int zfs_backup(zfs_handle_t *, zfs_handle_t *);
 extern int zfs_restore(const char *, int, int, int);
diff --git a/usr/src/lib/libzfs/common/libzfs_changelist.c b/usr/src/lib/libzfs/common/libzfs_changelist.c
index 497461e19f..57fcc1497c 100644
--- a/usr/src/lib/libzfs/common/libzfs_changelist.c
+++ b/usr/src/lib/libzfs/common/libzfs_changelist.c
@@ -20,7 +20,7 @@
  * CDDL HEADER END
  */
 /*
- * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
+ * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
  */
 
@@ -54,6 +54,7 @@
  *
  * Other interfaces:
  *
+ * changelist_remove() - remove a node from a gathered list
  * changelist_rename() - renames all datasets appropriately when doing a rename
  * changelist_unshare() - unshares all the nodes in a given changelist
  * changelist_haszonedchild() - check if there is any child exported to
@@ -74,6 +75,7 @@ struct prop_changelist {
 	uu_list_t		*cl_list;
 	int			cl_waslegacy;
 	int			cl_allchildren;
+	int			cl_alldependents;
 	int			cl_flags;
 	int			cl_haszonedchild;
 };
@@ -195,6 +197,28 @@ changelist_postfix(prop_changelist_t *clp)
 }
 
 /*
+ * Is this "dataset" a child of "parent"?
+ */
+static int
+isa_child_of(char *dataset, const char *parent)
+{
+	int len;
+
+	/* snapshot does not have a child */
+	if (strchr(parent, '@'))
+		return (FALSE);
+
+	len = strlen(parent);
+
+	if (strncmp(dataset, parent, len) == 0 &&
+	    (dataset[len] == '/' || dataset[len] == '\0'))
+		return (TRUE);
+	else
+		return (FALSE);
+
+}
+
+/*
  * If we rename a filesystem, and child filesystem handles are no longer valid,
  * since we identify datasets by their name in the ZFS namespace.  So, we have
  * to go through and fix up all the names appropriately.  We could do this
@@ -210,6 +234,12 @@ changelist_rename(prop_changelist_t *clp, const char *src, const char *dst)
 	for (cn = uu_list_first(clp->cl_list); cn != NULL;
 	    cn = uu_list_next(clp->cl_list, cn)) {
 		/*
+		 * Do not rename a clone that's not in the source hierarchy.
+		 */
+		if (!isa_child_of(cn->cn_handle->zfs_name, src))
+			continue;
+
+		/*
 		 * Destroy the previous mountpoint if needed.
 		 */
 		remove_mountpoint(cn->cn_handle);
@@ -257,6 +287,26 @@ changelist_haszonedchild(prop_changelist_t *clp)
 }
 
 /*
+ * Remove a node from a gathered list.
+ */
+void
+changelist_remove(zfs_handle_t *zhp, prop_changelist_t *clp)
+{
+	prop_changenode_t *cn;
+
+	for (cn = uu_list_first(clp->cl_list); cn != NULL;
+	    cn = uu_list_next(clp->cl_list, cn)) {
+
+		if (strcmp(cn->cn_handle->zfs_name, zhp->zfs_name) == 0) {
+			uu_list_remove(clp->cl_list, cn);
+			zfs_close(cn->cn_handle);
+			free(cn);
+			return;
+		}
+	}
+}
+
+/*
  * Release any memory associated with a changelist.
  */
 void
@@ -306,8 +356,8 @@ change_one(zfs_handle_t *zhp, void *data)
 	    FALSE) != 0)
 		return (0);
 
-	if (clp->cl_allchildren || sourcetype == ZFS_SRC_DEFAULT ||
-	    sourcetype == ZFS_SRC_INHERITED) {
+	if (clp->cl_alldependents || clp->cl_allchildren ||
+	    sourcetype == ZFS_SRC_DEFAULT || sourcetype == ZFS_SRC_INHERITED) {
 		cn = zfs_malloc(sizeof (prop_changenode_t));
 
 		cn->cn_handle = zhp;
@@ -320,10 +370,16 @@ change_one(zfs_handle_t *zhp, void *data)
 			clp->cl_haszonedchild = TRUE;
 
 		uu_list_node_init(cn, &cn->cn_listnode, clp->cl_pool);
-		verify(uu_list_insert_before(clp->cl_list,
-		    uu_list_first(clp->cl_list), cn) == 0);
 
-		return (zfs_iter_children(zhp, change_one, data));
+		if (clp->cl_alldependents) {
+			verify(uu_list_insert_after(clp->cl_list,
+				uu_list_last(clp->cl_list), cn) == 0);
+			return (0);
+		} else {
+			verify(uu_list_insert_before(clp->cl_list,
+				uu_list_first(clp->cl_list), cn) == 0);
+			return (zfs_iter_children(zhp, change_one, data));
+		}
 	} else {
 		zfs_close(zhp);
 	}
@@ -361,8 +417,14 @@ changelist_gather(zfs_handle_t *zhp, zfs_prop_t prop, int flags)
 	 * If this is a rename or the 'zoned' property, we pretend we're
 	 * changing the mountpoint and flag it so we can catch all children in
 	 * change_one().
+	 *
+	 * Flag cl_alldependents to catch all children plus the
+	 * dependents (clones) that are not in the hierarchy.
 	 */
-	if (prop == ZFS_PROP_NAME || prop == ZFS_PROP_ZONED) {
+	if (prop == ZFS_PROP_NAME) {
+		clp->cl_prop = ZFS_PROP_MOUNTPOINT;
+		clp->cl_alldependents = TRUE;
+	} else if (prop == ZFS_PROP_ZONED) {
 		clp->cl_prop = ZFS_PROP_MOUNTPOINT;
 		clp->cl_allchildren = TRUE;
 	} else {
@@ -374,7 +436,12 @@ changelist_gather(zfs_handle_t *zhp, zfs_prop_t prop, int flags)
 	    clp->cl_prop != ZFS_PROP_SHARENFS)
 		return (clp);
 
-	if (zfs_iter_children(zhp, change_one, clp) != 0) {
+	if (clp->cl_alldependents) {
+		if (zfs_iter_dependents(zhp, change_one, clp) != 0) {
+			changelist_free(clp);
+			return (NULL);
+		}
+	} else if (zfs_iter_children(zhp, change_one, clp) != 0) {
 		changelist_free(clp);
 		return (NULL);
 	}
diff --git a/usr/src/lib/libzfs/common/libzfs_dataset.c b/usr/src/lib/libzfs/common/libzfs_dataset.c
index 95a1b6a38a..1299a42f3f 100644
--- a/usr/src/lib/libzfs/common/libzfs_dataset.c
+++ b/usr/src/lib/libzfs/common/libzfs_dataset.c
@@ -20,7 +20,7 @@
  * CDDL HEADER END
  */
 /*
- * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
+ * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
  */
 
@@ -39,6 +39,7 @@
 #include <zone.h>
 #include <sys/mntent.h>
 #include <sys/mnttab.h>
+#include <sys/mount.h>
 
 #include <sys/spa.h>
 #include <sys/zio.h>
@@ -2589,11 +2590,55 @@ zfs_restore(const char *tosnap, int isprefix, int verbose, int dryrun)
 }
 
 /*
- * Rollback the given dataset to the previous snapshot.  It is up to the caller
- * to verify that there is a previous snapshot available.
+ * Destroy any more recent snapshots.  We invoke this callback on any dependents
+ * of the snapshot first.  If the 'cb_dependent' member is non-zero, then this
+ * is a dependent and we should just destroy it without checking the transaction
+ * group.
  */
-int
-zfs_rollback(zfs_handle_t *zhp)
+typedef struct rollback_data {
+	const char	*cb_target;		/* the snapshot */
+	uint64_t	cb_create;		/* creation time reference */
+	prop_changelist_t *cb_clp;		/* changelist pointer */
+	int		cb_error;
+	int		cb_dependent;
+} rollback_data_t;
+
+static int
+rollback_destroy(zfs_handle_t *zhp, void *data)
+{
+	rollback_data_t *cbp = data;
+
+	if (!cbp->cb_dependent) {
+		if (strcmp(zhp->zfs_name, cbp->cb_target) != 0 &&
+		    zfs_get_type(zhp) == ZFS_TYPE_SNAPSHOT &&
+		    zfs_prop_get_int(zhp, ZFS_PROP_CREATETXG) >
+		    cbp->cb_create) {
+
+			cbp->cb_dependent = TRUE;
+			(void) zfs_iter_dependents(zhp, rollback_destroy, cbp);
+			cbp->cb_dependent = FALSE;
+
+			if (zfs_destroy(zhp) != 0)
+				cbp->cb_error = 1;
+			else
+				changelist_remove(zhp, cbp->cb_clp);
+		}
+	} else {
+		if (zfs_destroy(zhp) != 0)
+			cbp->cb_error = 1;
+		else
+			changelist_remove(zhp, cbp->cb_clp);
+	}
+
+	zfs_close(zhp);
+	return (0);
+}
+
+/*
+ * Rollback the dataset to its latest snapshot.
+ */
+static int
+do_rollback(zfs_handle_t *zhp)
 {
 	int ret;
 	zfs_cmd_t zc = { 0 };
@@ -2677,6 +2722,66 @@ zfs_rollback(zfs_handle_t *zhp)
 }
 
 /*
+ * Given a dataset, rollback to a specific snapshot, discarding any
+ * data changes since then and making it the active dataset.
+ *
+ * Any snapshots more recent than the target are destroyed, along with
+ * their dependents.
+ */
+int
+zfs_rollback(zfs_handle_t *zhp, zfs_handle_t *snap, int flag)
+{
+	int ret;
+	rollback_data_t cb = { 0 };
+	prop_changelist_t *clp;
+
+	/*
+	 * Unmount all dependendents of the dataset and the dataset itself.
+	 * The list we need to gather is the same as for doing rename
+	 */
+	clp = changelist_gather(zhp, ZFS_PROP_NAME, flag ? MS_FORCE: 0);
+	if (clp == NULL)
+		return (-1);
+
+	if ((ret = changelist_prefix(clp)) != 0)
+		goto out;
+
+	/*
+	 * Destroy all recent snapshots and its dependends.
+	 */
+	cb.cb_target = snap->zfs_name;
+	cb.cb_create = zfs_prop_get_int(snap, ZFS_PROP_CREATETXG);
+	cb.cb_clp = clp;
+	(void) zfs_iter_children(zhp, rollback_destroy, &cb);
+
+	if ((ret = cb.cb_error) != 0) {
+		(void) changelist_postfix(clp);
+		goto out;
+	}
+
+	/*
+	 * Now that we have verified that the snapshot is the latest,
+	 * rollback to the given snapshot.
+	 */
+	ret = do_rollback(zhp);
+
+	if (ret != 0) {
+		(void) changelist_postfix(clp);
+		goto out;
+	}
+
+	/*
+	 * We only want to re-mount the filesystem if it was mounted in the
+	 * first place.
+	 */
+	ret = changelist_postfix(clp);
+
+out:
+	changelist_free(clp);
+	return (ret);
+}
+
+/*
  * Iterate over all dependents for a given dataset.  This includes both
  * hierarchical dependents (children) and data dependents (snapshots and
  * clones).  The bulk of the processing occurs in get_dependents() in
diff --git a/usr/src/lib/libzfs/common/libzfs_impl.h b/usr/src/lib/libzfs/common/libzfs_impl.h
index c9e51de33b..cb1400b1b0 100644
--- a/usr/src/lib/libzfs/common/libzfs_impl.h
+++ b/usr/src/lib/libzfs/common/libzfs_impl.h
@@ -20,7 +20,7 @@
  * CDDL HEADER END
  */
 /*
- * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
+ * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
  */
 
@@ -82,6 +82,7 @@ typedef struct prop_changelist prop_changelist_t;
 int changelist_prefix(prop_changelist_t *);
 int changelist_postfix(prop_changelist_t *);
 void changelist_rename(prop_changelist_t *, const char *, const char *);
+void changelist_remove(zfs_handle_t *, prop_changelist_t *);
 void changelist_free(prop_changelist_t *);
 prop_changelist_t *changelist_gather(zfs_handle_t *, zfs_prop_t, int);
 int changelist_unshare(prop_changelist_t *);