From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from terminus.zytor.com ([198.137.202.10]:47839 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751656Ab2FSAaA (ORCPT ); Mon, 18 Jun 2012 20:30:00 -0400 Message-ID: <4FDFC807.2080209@zytor.com> Date: Mon, 18 Jun 2012 17:29:59 -0700 From: "H. Peter Anvin" MIME-Version: 1.0 To: linux-btrfs@vger.kernel.org Subject: Device names Content-Type: text/plain; charset=UTF-8 Sender: linux-btrfs-owner@vger.kernel.org List-ID: I just found out that all the device handling in btrfs is based on pathnames, but shorter pathnames (1024) that PATH_MAX (4096). This is confusing, and concerning for multiple reasons: 1. pathnames are namespace-specific; what is a pathname in one namespace might not be in another. 2. different truncation rules in the rest of the kernel. There seem to be no way one can do the equivalent of BTRFS_IOC_DEV_INFO but actually get a device number or other stable information for that device (that could be compared to a file descriptor for verification); is that an accurate observation? -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf.