diff --git a/fs/nilfs2/sufile.c b/fs/nilfs2/sufile.c
index 150845a43225..d85d3c758d7b 100644
--- a/fs/nilfs2/sufile.c
+++ b/fs/nilfs2/sufile.c
@@ -782,6 +782,15 @@ int nilfs_sufile_resize(struct inode *sufile, __u64 newnsegs)
 			goto out_header;
 
 		sui->ncleansegs -= nsegs - newnsegs;
+
+		/*
+		 * If the sufile is successfully truncated, immediately adjust
+		 * the segment allocation space while locking the semaphore
+		 * "mi_sem" so that nilfs_sufile_alloc() never allocates
+		 * segments in the truncated space.
+		 */
+		sui->allocmax = newnsegs - 1;
+		sui->allocmin = 0;
 	}
 
 	kaddr = kmap_atomic(header_bh->b_page);