From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Chinner Subject: Re: [PATCH] Btrfs: return EUCLEAN rather than ENXIO once internal error has occurred for SEEK_DATA/SEEK_HOLE inquiry Date: Thu, 9 Feb 2012 15:51:18 +1100 Message-ID: <20120209045118.GE7479@dastard> References: <4F334178.7030704@oracle.com> <4F3346CF.3090908@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "linux-btrfs@vger.kernel.org" To: Jeff Liu Return-path: In-Reply-To: <4F3346CF.3090908@oracle.com> List-ID: On Thu, Feb 09, 2012 at 12:08:47PM +0800, Jeff Liu wrote: > On 02/09/2012 11:46 AM, Jeff Liu wrote: > > > By referring to http://linux.die.net/man/2/lseek, return ENXIO only > > when "offset beyond EOF" for either SEEK_DATA or SEEK_HOLE inquiry. > > But we return it in case of internal issue too if btrfs_get_extent_fiemap() failed > > due to other issues. This will confuse the user applications to be expecting ENXIO when > > trying to find a specific data or hole location once it has occurred. > > > > Thanks Dave for pointing that out in XFS thread. > > > > This patch fix it to return EUCLEAN, or maybe another particular errno is more reasonable in Btrfs to indicate this fatal error? > > Or maybe just return the error that was happened at internal routine, to > give user more accurate error info, which is better? Return the internal error unchanged - a failure to read the extent list (EIO) is different to a corruption detected in the extent map read from disk (EUCLEAN). Having a user report the appropriate error makes our life much simpler when it comes to trying to understand their problem.... Cheers, Dave. -- Dave Chinner david@fromorbit.com