From: Jim Meyering Subject: Re: bug#6131: [PATCH]: fiemap support for efficient sparse file copy Date: Fri, 11 Jun 2010 14:38:08 +0200 Message-ID: <87typ9iw27.fsf@meyering.net> References: <4BE41FFF.4020809@oracle.com> <871vdho68j.fsf@meyering.net> <4BEC0BCC.3080906@oracle.com> <87k4qyl6lw.fsf@meyering.net> <4BF683CC.3060407@oracle.com> <4BF6ABE7.3020600@oracle.com> <877hmpeivx.fsf@meyering.net> <4BFF763A.9010205@oracle.com> <8763286kni.fsf@meyering.net> <4C0275FA.1030901@oracle.com> <874ohpywri.fsf@meyering.net> <87y6exuc5i.fsf@meyering.net> <874ohdu5b8.fsf@meyering.net> <87eighs1t9.fsf@meyering.net> <4C0FA93C.6020205@oracle.com> <87iq5sp7eg.fsf@meyering.net> <4C108CB9.8010805@oracle.com> <4C11798B.6090500@cs.ucla.edu> <4C1183FD.9010502@oracle.com> <4C11F451.8040304@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Sunil Mushran , Paul Eggert , bug-coreutils@gnu.org, Joel Becker , Chris Mason , "linux-ext4\@vger.kernel.org" , Tao Ma To: "jeff.liu" Return-path: Received: from smtp1-g21.free.fr ([212.27.42.1]:48682 "EHLO smtp1-g21.free.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754326Ab0FKMiS (ORCPT ); Fri, 11 Jun 2010 08:38:18 -0400 In-Reply-To: <4C11F451.8040304@oracle.com> (jeff liu's message of "Fri, 11 Jun 2010 16:31:13 +0800") Sender: linux-ext4-owner@vger.kernel.org List-ID: jeff.liu wrote: > Sunil Mushran wrote: ... >> I guess we'll have to use FIEMAP_FLAG_SYNC. > Hi Sunil, > > Thanks for the comments. > So we can ensure the source file synced before mapping in this way. > > Hi Jim and Paul, > > How about the tiny patch below? ... > Subject: [PATCH 1/1] copy.c: add FIEMAP_FLAG_SYNC to fiemap ioctl > > * src/copy.c (fiemap_copy): Force kernel to sync the source > file before mapping. > > Signed-off-by: Jie Liu > --- > src/copy.c | 1 + > 1 files changed, 1 insertions(+), 0 deletions(-) > > diff --git a/src/copy.c b/src/copy.c > index f149be4..f48c74d 100644 > --- a/src/copy.c > +++ b/src/copy.c > @@ -191,6 +191,7 @@ fiemap_copy (int src_fd, int dest_fd, size_t buf_size, > do > { > fiemap->fm_length = FIEMAP_MAX_OFFSET; > + fiemap->fm_flags = FIEMAP_FLAG_SYNC; > fiemap->fm_extent_count = count; Thanks to both of you. That patch looks fine, Jeff. However, at least with ext4 and fedora 13, I require this change to pass "make check". Note the new entry in the "flags" column: ==> ff2 <== Filesystem type is: ef53 File size of j2 is 2048 (1 block, blocksize 4096) ext logical physical expected length flags 0 0 0 1 unknown,delalloc,eof j2: 1 extent found So I will apply the test-fixing patch first, then your change, Jeff, and then rebase to the latest on master. >From 484903dc41246cb3c774f178f695725561b105a0 Mon Sep 17 00:00:00 2001 From: Jim Meyering Date: Fri, 11 Jun 2010 14:34:03 +0200 Subject: [PATCH 1/2] tests: accommodate varying filefrag -v "flags" output * tests/cp/sparse-fiemap: Accommodate values other than "eof" in the "flags" column of filefrag -v output --- tests/cp/sparse-fiemap | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/tests/cp/sparse-fiemap b/tests/cp/sparse-fiemap index dc0cf60..b6b1103 100755 --- a/tests/cp/sparse-fiemap +++ b/tests/cp/sparse-fiemap @@ -68,10 +68,11 @@ $PERL -e 1 || skip_test_ 'skipping part of this test; you lack perl' # Extract logical block number and length pairs from filefrag -v output. # The initial sed is to remove the "eof" from the normally-empty "flags" field. +# Similarly, remove flags values like "unknown,delalloc,eof". # That is required when that final extent has no number in the "expected" field. f() { - sed 's/ eof$//' $@ \ + sed 's/ [a-z,][a-z,]*$//' $@ \ | awk '/^ *[0-9]/ {printf "%d %d ", $2 ,NF < 5 ? $NF : $5 } END {print ""}' } -- 1.7.1.501.g23b46