svn commit: r340593 - head/lib/libbe

[Kyle Evans]

Author: kevans
Date: Mon Nov 19 02:16:20 2018
New Revision: 340593
URL: https://svnweb.freebsd.org/changeset/base/340593

Log:
  libbe(3): Properly account for altroot when creating new BEs
  
  Previously we would blindly copy the 'mountpoint' property, which includes
  the altroot. The altroot needs to be snipped off prior to setting it on the
  new BE, though, or you'll end up with a new BE and a mountpoint of /mnt with
  altroot=/mnt
  
  MFC after:	3 days

Modified:
  head/lib/libbe/be.c
  head/lib/libbe/be_impl.h

Modified: head/lib/libbe/be.c
==============================================================================
--- head/lib/libbe/be.c	Mon Nov 19 02:12:08 2018	(r340592)
+++ head/lib/libbe/be.c	Mon Nov 19 02:16:20 2018	(r340593)
@@ -305,6 +305,7 @@ be_deep_clone_prop(int prop, void *cb)
 	zprop_source_t src;
 	char pval[BE_MAXPATHLEN];
 	char source[BE_MAXPATHLEN];
+	char *val;
 
 	dccb = cb;
 	/* Skip some properties we don't want to touch */
@@ -324,7 +325,15 @@ be_deep_clone_prop(int prop, void *cb)
 	if (src != ZPROP_SRC_LOCAL)
 		return (ZPROP_CONT);
 
-	nvlist_add_string(dccb->props, zfs_prop_to_name(prop), (char *)pval);
+	/* Augment mountpoint with altroot, if needed */
+	val = pval;
+	if (prop == ZFS_PROP_MOUNTPOINT && *dccb->altroot != '\0') {
+		if (pval[strlen(dccb->altroot)] == '\0')
+			strlcpy(pval, "/", sizeof(pval));
+		else
+			val = pval + strlen(dccb->altroot);
+	}
+	nvlist_add_string(dccb->props, zfs_prop_to_name(prop), val);
 
 	return (ZPROP_CONT);
 }
@@ -367,6 +376,10 @@ be_deep_clone(zfs_handle_t *ds, void *data)
 
 	dccb.zhp = ds;
 	dccb.props = props;
+	if (zpool_get_prop(isdc->lbh->active_phandle, ZPOOL_PROP_ALTROOT,
+	    dccb.altroot, sizeof(dccb.altroot), NULL, true) != 0 ||
+	    strcmp(dccb.altroot, "-") == 0)
+		*dccb.altroot = '\0';
 	if (zprop_iter(be_deep_clone_prop, &dccb, B_FALSE, B_FALSE,
 	    ZFS_TYPE_FILESYSTEM) == ZPROP_INVAL)
 		return (-1);

Modified: head/lib/libbe/be_impl.h
==============================================================================
--- head/lib/libbe/be_impl.h	Mon Nov 19 02:12:08 2018	(r340592)
+++ head/lib/libbe/be_impl.h	Mon Nov 19 02:16:20 2018	(r340593)
@@ -55,6 +55,7 @@ struct libbe_deep_clone {
 struct libbe_dccb {
 	zfs_handle_t *zhp;
 	nvlist_t *props;
+	char altroot[MAXPATHLEN];
 };
 
 typedef struct prop_data {