diff --git a/include/ntfs-3g/attrib.h b/include/ntfs-3g/attrib.h
index 6fc5bc8b..3aeec198 100644
--- a/include/ntfs-3g/attrib.h
+++ b/include/ntfs-3g/attrib.h
@@ -340,7 +340,7 @@ extern int   ntfs_attr_exist(ntfs_inode *ni, const ATTR_TYPES type,
 			     ntfschar *name, u32 name_len);
 extern int   ntfs_attr_remove(ntfs_inode *ni, const ATTR_TYPES type,
 			      ntfschar *name, u32 name_len);
-extern long  ntfs_attr_get_free_bits(ntfs_attr *na);
+extern s64   ntfs_attr_get_free_bits(ntfs_attr *na);
 
 #endif /* defined _NTFS_ATTRIB_H */
 
diff --git a/libntfs-3g/attrib.c b/libntfs-3g/attrib.c
index eafcdb55..7b78cfa4 100644
--- a/libntfs-3g/attrib.c
+++ b/libntfs-3g/attrib.c
@@ -5042,15 +5042,15 @@ int ntfs_attr_remove(ntfs_inode *ni, const ATTR_TYPES type, ntfschar *name,
 	return ret;
 }
 
-long ntfs_attr_get_free_bits(ntfs_attr *na)
+s64 ntfs_attr_get_free_bits(ntfs_attr *na)
 {
 	u8 *buf;
-	long nr_free = 0;
+	s64 nr_free = 0;
 	s64 br, total = 0;
 
 	buf = ntfs_malloc(na->ni->vol->cluster_size);
 	if (!buf)
-		return -errno;
+		return -1;
 	while (1) {
 		int i, j;
 
@@ -5065,7 +5065,7 @@ long ntfs_attr_get_free_bits(ntfs_attr *na)
 	}
 	free(buf);
 	if (!total || br < 0)
-		return -errno;
+		return -1;
 	return nr_free;
 }
 
diff --git a/src/ntfs-3g.c b/src/ntfs-3g.c
index aa75d8dc..a307f2f2 100644
--- a/src/ntfs-3g.c
+++ b/src/ntfs-3g.c
@@ -167,10 +167,10 @@ static int ntfs_fuse_is_named_data_stream(const char *path)
 	return 0;
 }
 
-static long ntfs_get_nr_free_mft_records(ntfs_volume *vol)
+static s64 ntfs_get_nr_free_mft_records(ntfs_volume *vol)
 {
 	ntfs_attr *na = vol->mftbmp_na;
-	long nr_free = ntfs_attr_get_free_bits(na);
+	s64 nr_free = ntfs_attr_get_free_bits(na);
 
 	if (nr_free >= 0)
 		nr_free += (na->allocated_size - na->data_size) << 3;