6790687 libzfs mnttab caching ignores external changes

6791101 memory leak from libzfs_mnttab_init

1 files changed, 27 insertions, 3 deletions

diff --git a/usr/src/lib/libzfs/common/libzfs_dataset.c b/usr/src/lib/libzfs/common/libzfs_dataset.c
index 80dd06cb4a..a9f01ebc13 100644
--- a/usr/src/lib/libzfs/common/libzfs_dataset.c
+++ b/usr/src/lib/libzfs/common/libzfs_dataset.c
@@ -605,11 +605,15 @@ libzfs_mnttab_cache_compare(const void *arg1, const void *arg2)
 void
 libzfs_mnttab_init(libzfs_handle_t *hdl)
 {
-	struct mnttab entry;
-
 	assert(avl_numnodes(&hdl->libzfs_mnttab_cache) == 0);
 	avl_create(&hdl->libzfs_mnttab_cache, libzfs_mnttab_cache_compare,
 	    sizeof (mnttab_node_t), offsetof(mnttab_node_t, mtn_node));
+}
+
+void
+libzfs_mnttab_update(libzfs_handle_t *hdl)
+{
+	struct mnttab entry;
 
 	rewind(hdl->libzfs_mnttab);
 	while (getmntent(hdl->libzfs_mnttab, &entry) == 0) {
@@ -642,6 +646,12 @@ libzfs_mnttab_fini(libzfs_handle_t *hdl)
 	avl_destroy(&hdl->libzfs_mnttab_cache);
 }
 
+void
+libzfs_mnttab_cache(libzfs_handle_t *hdl, boolean_t enable)
+{
+	hdl->libzfs_mnttab_enable = enable;
+}
+
 int
 libzfs_mnttab_find(libzfs_handle_t *hdl, const char *fsname,
     struct mnttab *entry)
@@ -649,8 +659,22 @@ libzfs_mnttab_find(libzfs_handle_t *hdl, const char *fsname,
 	mnttab_node_t find;
 	mnttab_node_t *mtn;
 
+	if (!hdl->libzfs_mnttab_enable) {
+		struct mnttab srch = { 0 };
+
+		if (avl_numnodes(&hdl->libzfs_mnttab_cache))
+			libzfs_mnttab_fini(hdl);
+		rewind(hdl->libzfs_mnttab);
+		srch.mnt_special = (char *)fsname;
+		srch.mnt_fstype = MNTTYPE_ZFS;
+		if (getmntany(hdl->libzfs_mnttab, entry, &srch) == 0)
+			return (0);
+		else
+			return (ENOENT);
+	}
+
 	if (avl_numnodes(&hdl->libzfs_mnttab_cache) == 0)
-		libzfs_mnttab_init(hdl);
+		libzfs_mnttab_update(hdl);
 
 	find.mtn_mt.mnt_special = (char *)fsname;
 	mtn = avl_find(&hdl->libzfs_mnttab_cache, &find, NULL);