From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay2.corp.sgi.com [137.38.102.29]) by oss.sgi.com (Postfix) with ESMTP id 37A097F6B for ; Wed, 16 Apr 2014 01:36:30 -0500 (CDT) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by relay2.corp.sgi.com (Postfix) with ESMTP id 1140130404E for ; Tue, 15 Apr 2014 23:36:30 -0700 (PDT) Received: from bombadil.infradead.org ([198.137.202.9]) by cuda.sgi.com with ESMTP id RMzBkWVQtELj0LK3 (version=TLSv1 cipher=AES256-SHA bits=256 verify=NO) for ; Tue, 15 Apr 2014 23:36:28 -0700 (PDT) Date: Tue, 15 Apr 2014 23:36:18 -0700 From: Christoph Hellwig Subject: Re: [PATCH 0/6][RFC] Introduce FALLOC_FL_ZERO_RANGE flag for fallocate Message-ID: <20140416063618.GA12498@infradead.org> References: <1392649703-10772-1-git-send-email-lczerner@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1392649703-10772-1-git-send-email-lczerner@redhat.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Lukas Czerner Cc: linux-man@vger.kernel.org, tytso@mit.edu, xfs@oss.sgi.com, Michael Kerrisk , linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org On Mon, Feb 17, 2014 at 04:08:17PM +0100, Lukas Czerner wrote: > Introduce new FALLOC_FL_ZERO_RANGE flag for fallocate. This has the same > functionality as xfs ioctl XFS_IOC_ZERO_RANGE. Lukas, can you please also send a man page update for FALLOC_FL_ZERO_RANGE now that is has been merged? > > It can be used to convert a range of file to zeros preferably without > issuing data IO. Blocks should be preallocated for the regions that span > holes in the file, and the entire range is preferable converted to > unwritten extents - even though file system may choose to zero out the > extent or do whatever which will result in reading zeros from the range > while the range remains allocated for the file. > > This can be also used to preallocate blocks past EOF in the same way as > with fallocate. Flag FALLOC_FL_KEEP_SIZE which should cause the inode > size to remain the same. > > You can test this feature yourself using xfstests, of fallocate(1) however > you'll need patches for util_linux, xfsprogs and xfstests which you > can find here: > > http://people.redhat.com/lczerner/zero_range/ _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs