diff --git a/fs/xfs/xfs_fs_subr.c b/fs/xfs/xfs_fs_subr.c
index 652b875..6e9b052 100644
--- a/fs/xfs/xfs_fs_subr.c
+++ b/fs/xfs/xfs_fs_subr.c
@@ -34,7 +34,8 @@ xfs_tosspages(
 {
 	/* can't toss partial tail pages, so mask them out */
 	last &= ~(PAGE_SIZE - 1);
-	truncate_inode_pages_range(VFS_I(ip)->i_mapping, first, last - 1);
+	truncate_inode_pages_range(VFS_I(ip)->i_mapping, first,
+				   last == -1 ? LLONG_MAX : last);
 }
 
 int
@@ -53,7 +54,8 @@ xfs_flushinval_pages(
 	ret = filemap_write_and_wait_range(mapping, first,
 				last == -1 ? LLONG_MAX : last);
 	if (!ret)
-		truncate_inode_pages_range(mapping, first, last);
+		truncate_inode_pages_range(mapping, first,
+					   last == -1 ? LLONG_MAX : last);
 	return -ret;
 }