From mboxrd@z Thu Jan 1 00:00:00 1970 From: Namjae Jeon Subject: [PATCH v4 10/10] manpage: update FALLOC_FL_COLLAPSE_RANGE flag in fallocate Date: Sun, 8 Dec 2013 23:02:06 +0900 Message-ID: <1386511326-3601-1-git-send-email-linkinjeon@gmail.com> Cc: linux-fsdevel@vger.kernel.org, xfs@oss.sgi.com, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, Namjae Jeon , Namjae Jeon , Ashish Sangwan To: viro@zeniv.linux.org.uk, dchinner@fromorbit.com, bpm@sgi.com, tytso@mit.edu, adilger.kernel@dilger.ca, jack@suse.cz Return-path: Received: from mail-pb0-f52.google.com ([209.85.160.52]:39723 "EHLO mail-pb0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759623Ab3LHOCO (ORCPT ); Sun, 8 Dec 2013 09:02:14 -0500 Sender: linux-fsdevel-owner@vger.kernel.org List-ID: From: Namjae Jeon Update FALLOC_FL_COLLAPSE_RANGE flag in fallocate. Signed-off-by: Namjae Jeon Signed-off-by: Ashish Sangwan --- man2/fallocate.2 | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/man2/fallocate.2 b/man2/fallocate.2 index ec9011c..69a4dbd 100644 --- a/man2/fallocate.2 +++ b/man2/fallocate.2 @@ -1,5 +1,6 @@ .\" Copyright (c) 2007 Silicon Graphics, Inc. All Rights Reserved .\" Written by Dave Chinner +.\" Updated by Namjae Jeon .\" .\" %%%LICENSE_START(GPLv2_ONELINE) .\" May be distributed as per GNU General Public License version 2. @@ -7,6 +8,7 @@ .\" .\" 2011-09-19: Added FALLOC_FL_PUNCH_HOLE .\" 2011-09-19: Substantial restructuring of the page +.\" 2013-11-10: Added FALLOC_FL_COLLAPSE_RANGE .\" .TH FALLOCATE 2 2013-11-08 "Linux" "Linux Programmer's Manual" .SH NAME @@ -113,6 +115,25 @@ does not change. Not all filesystems support .BR FALLOC_FL_PUNCH_HOLE ; if a filesystem doesn't support the operation, an error is returned. +.SS Collapsing file space +Specifiying the +.BR FALLOC_FL_COLLAPSE_RANGE +flag in +.I mode +collpse space in the byte range starting at +.I offset +and continuing for +.I len +bytes. Within the specified range, it first de-allocates blocks and eliminates +the hole created in this process by shifting data blocks into the hole. + +Different filesystem may implement different limitatios on the granularity of +the operation. Most filesystem will limit operations to filesystem block size +boundaries, but this boundary may be larger or smaller depending +on the filesystem and/or the configuration of the filesystem or file. + +If filesystem has such limitation on granularity, It will return error(EINVAL). + .SH RETURN VALUE On success, .BR fallocate () -- 1.7.9.5