Add ignore-subtree and restrict-subtree settings

Add {nis,schema-compat}-ignore-subtree (subtrees under which we ignore
contents and updates )and {nis,schema-compat}-restrict-subtree (subtrees
out of which we ignore contents and updates, if set) settings, and
default the former to "cn=tasks,cn=config".

This should avoid cases where we're looking through the ldbm backend for
entries which have a dangling reference to a newly-added task (which,
because it's in the DSE, means we acquire an ldbm lock after acquiring
our internal lock) while also updating a compat entry after its source
entry is modified (for example, by the memberOf plugin, which results in
us attempting to acquire our lock while the ldbm lock is already held).

1 files changed, 6 insertions, 4 deletions

diff --git a/src/backend.h b/src/backend.h
index 8c00dd4..7974aae 100644
--- a/src/backend.h
+++ b/src/backend.h
@@ -46,10 +46,12 @@ struct backend_shr_set_data {
 	/* Configuration flag indicating whether or not we try to skip
 	 * recomputing data in this map. */
 	unsigned int skip_uninteresting_updates:1;
-	/* Subtrees under which all of the contents that we care about will be
-	 * stored.  Other locaoins will be silently ignored. */
-	const struct slapi_dn **relevant_subtrees;
-	/* Subtrees under which we ignore contents. */
+	/* Subtrees under which all of the contents that we care about, and
+	 * anything that refers to content that we care about, will be stored.
+	 * Other locations will be silently ignored if this list contains any
+	 * values. */
+	const struct slapi_dn **restrict_subtrees;
+	/* Subtrees under which we ignore contents and updates. */
 	const struct slapi_dn **ignore_subtrees;
 	struct backend_set_data *self;
 };