From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755271Ab0I2TVh (ORCPT ); Wed, 29 Sep 2010 15:21:37 -0400 Received: from sj-iport-6.cisco.com ([171.71.176.117]:8816 "EHLO sj-iport-6.cisco.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754662Ab0I2TVg (ORCPT ); Wed, 29 Sep 2010 15:21:36 -0400 Authentication-Results: sj-iport-6.cisco.com; dkim=neutral (message not signed) header.i=none X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AvsEAC4vo0yrRN+K/2dsb2JhbACiHHGrRZxohUQEhFCFaoR5 X-IronPort-AV: E=Sophos;i="4.57,255,1283731200"; d="scan'208";a="596712936" From: Roland Dreier To: Arnd Bergmann Cc: Steve Wise , linux-rdma@vger.kernel.org, linux-next@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] RDMA/cxgb4: Add default_llseek to debugfs files. References: <20100929141112.26944.21931.stgit@build.ogc.int> <201009292117.54828.arnd@arndb.de> X-Message-Flag: Warning: May contain useful information Date: Wed, 29 Sep 2010 12:21:14 -0700 In-Reply-To: <201009292117.54828.arnd@arndb.de> (Arnd Bergmann's message of "Wed, 29 Sep 2010 21:17:54 +0200") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > The main difference between default_llseek and generic_file_llseek > is that default_llseek doesn't care about the maximum file size > of the underlying file system, which is ULONG_MAX on debugfs, > so they are equivalent. I thought default_llseek also takes the BKL still? > In general, the preferred one is no_llseek for those files where > you know you do not need to seek. If you do, I'd use default_llseek > for character devices and generic_file_llseek for file systems > that set the s_maxbytes. The case in question is for debugfs files, so we should use generic_file_llseek, right? - R.