From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 57325339BF; Thu, 7 Mar 2024 23:17:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709853469; cv=none; b=TEX0W+KYgSb7HNDAynVR/n3941v1MRHTIgB7nh/elu0Ve6tFqAnXQFLHa8VVcrLwFxyAUoxJx/ekqV1O3oF/gaBhiYZDRiCp1BlB3rCheXk77ie5cxR9Jpm1grI4AxlZrSi2uuUmkncoVxPcMMbFPOQgO3Gs1noyfLHyumUieVw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709853469; c=relaxed/simple; bh=bWtbE5gm88lFI6iVlchHoyZVNppdW+bGltTULtpI0ec=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=LqrfaIXqSnN6Qbc8cfB1aGK2NYr7XODNv3WhzM2mpEc8FXYJLfD3NU/sV5C1/fIqjw9eK6lDpirmYnLh3ijxUNKKs0qugS07uvZKgbu6plKnE0S8vpzFdzA8CtYoVsQLT4WXL+xqSCrPKG+BWipdOE19JkJF19r68CcOjirrnQE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=CtC2q5ix; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="CtC2q5ix" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BD4C6C433C7; Thu, 7 Mar 2024 23:17:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1709853468; bh=bWtbE5gm88lFI6iVlchHoyZVNppdW+bGltTULtpI0ec=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=CtC2q5ixjQuo82ZkffHFSFholhnmbPOh4MAWvBVGxXfB4vTzatSMERZgkNcKVQeeX Z8KMDJSz4K3ZbRSi2jfiot6gY+RfhxQst5rmM2Y6QeGuvQrVAV6EyrZERDFmmqrX+r mnPnUoBSZAgI+wM2UetZNqSMvBEoJzKiNJ1+F/PU+BtF6VkZ7tjzdOUwz0x7pVdegF wkRjd5Lg2SeaAZoIkHLF28ZFrjlX2M4/ZHMh4m/ukE9Y2qKt1eRdLZlsH1mp2ApMdg RI0DSYZJQ7dYYPFbruW7AWdCHk7vkGEg0jVOqAt8p+W48Pn5mM6KbjmCn1p/BXZUqT 6MD70luBuRrkQ== Date: Thu, 7 Mar 2024 15:17:48 -0800 From: "Darrick J. Wong" To: Zorro Lang Cc: linux-xfs@vger.kernel.org, fstests@vger.kernel.org Subject: Re: [PATCH v1.1 8/8] xfs: test for premature ENOSPC with large cow delalloc extents Message-ID: <20240307231748.GE1927156@frogsfrogsfrogs> References: <170899915207.896550.7285890351450610430.stgit@frogsfrogsfrogs> <170899915333.896550.18395785595853879309.stgit@frogsfrogsfrogs> <20240301175202.GK1927156@frogsfrogsfrogs> <20240302205056.saexqlexlmwpfy4e@dell-per750-06-vm-08.rhts.eng.pek2.redhat.com> Precedence: bulk X-Mailing-List: linux-xfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240302205056.saexqlexlmwpfy4e@dell-per750-06-vm-08.rhts.eng.pek2.redhat.com> On Sun, Mar 03, 2024 at 04:50:56AM +0800, Zorro Lang wrote: > On Fri, Mar 01, 2024 at 09:52:02AM -0800, Darrick J. Wong wrote: > > From: Darrick J. Wong > > > > On a higly fragmented filesystem a Direct IO write can fail with -ENOSPC error > > even though the filesystem has sufficient number of free blocks. > > > > This occurs if the file offset range on which the write operation is being > > performed has a delalloc extent in the cow fork and this delalloc extent > > begins much before the Direct IO range. > > > > In such a scenario, xfs_reflink_allocate_cow() invokes xfs_bmapi_write() to > > allocate the blocks mapped by the delalloc extent. The extent thus allocated > > may not cover the beginning of file offset range on which the Direct IO write > > was issued. Hence xfs_reflink_allocate_cow() ends up returning -ENOSPC. > > > > This test addresses this issue. > > > > Signed-off-by: Darrick J. Wong > > --- > > v1.1: address some missing bits and remove extraneous code > > --- > > common/rc | 14 ++++++++ > > tests/xfs/1923 | 86 ++++++++++++++++++++++++++++++++++++++++++++++++++++ > > tests/xfs/1923.out | 8 +++++ > > 3 files changed, 108 insertions(+) > > create mode 100755 tests/xfs/1923 > > create mode 100644 tests/xfs/1923.out > > > > diff --git a/common/rc b/common/rc > > index 30c44dddd9..d3a2a0718b 100644 > > --- a/common/rc > > +++ b/common/rc > > @@ -1873,6 +1873,20 @@ _require_scratch_delalloc() > > _scratch_unmount > > } > > > > +# Require test fs supports delay allocation. > > +_require_test_delalloc() > > +{ > > + _require_command "$FILEFRAG_PROG" filefrag > > + > > + rm -f $TEST_DIR/testy > > + $XFS_IO_PROG -f -c 'pwrite 0 64k' $TEST_DIR/testy &> /dev/null > > + $FILEFRAG_PROG -v $TEST_DIR/testy 2>&1 | grep -q delalloc > > + res=$? > > + rm -f $TEST_DIR/testy > > + test $res -eq 0 || \ > > + _notrun "test requires delayed allocation buffered writes" > > +} > > + > > # this test needs a test partition - check we're ok & mount it > > # > > _require_test() > > diff --git a/tests/xfs/1923 b/tests/xfs/1923 > > new file mode 100755 > > index 0000000000..7068fda64c > > --- /dev/null > > +++ b/tests/xfs/1923 > > @@ -0,0 +1,86 @@ > > +#! /bin/bash > > +# SPDX-License-Identifier: GPL-2.0 > > +# Copyright (c) 2022-2024 Oracle. All Rights Reserved. > > +# > > +# FS QA Test No. 1923 > > +# > > +# This is a regression test for "xfs: Fix false ENOSPC when performing direct > > +# write on a delalloc extent in cow fork". If there is a lot of free space but > > +# it is very fragmented, it's possible that a very large delalloc reservation > > +# could be created in the CoW fork by a buffered write. If a directio write > > +# tries to convert the delalloc reservation to a real extent, it's possible > > +# that the allocation will succeed but fail to convert even the first block of > > +# the directio write range. In this case, XFS will return ENOSPC even though > > +# all it needed to do was to keep converting until the allocator returns ENOSPC > > +# or the first block of the direct write got some space. > > +# > > +. ./common/preamble > > +_begin_fstest auto quick clone > > + > > +_cleanup() > > +{ > > + cd / > > + rm -f $file1 $file2 $fragmentedfile > > +} > > + > > +# Import common functions. > > +. ./common/reflink > > +. ./common/inject > > + > > +# real QA test starts here > > +_fixed_by_kernel_commit d62113303d69 \ > > + "xfs: Fix false ENOSPC when performing direct write on a delalloc extent in cow fork" > > + > > +# Modify as appropriate. > > +_supported_fs xfs > > +_require_test_program "punch-alternating" > > +_require_test_reflink > > +_require_xfs_io_error_injection "bmap_alloc_minlen_extent" > > +_require_test_delalloc > > + > > +file1=$TEST_DIR/file1.$seq > > +file2=$TEST_DIR/file2.$seq > > +fragmentedfile=$TEST_DIR/fragmentedfile.$seq > > + > > +rm -f $file1 $file2 $fragmentedfile > > + > > +# COW operates on pages, so we must not perform operations in units smaller > > +# than a page. > > +blksz=$(_get_file_block_size $TEST_DIR) > > +pagesz=$(_get_page_size) > > +if (( $blksz < $pagesz )); then > > + blksz=$pagesz > > +fi > > + > > +echo "Create source file" > > +$XFS_IO_PROG -f -c "pwrite 0 $((blksz * 256))" $file1 >> $seqres.full > > + > > +sync > > + > > +echo "Create Reflinked file" > > +_cp_reflink $file1 $file2 >> $seqres.full > > + > > +echo "Set cowextsize" > > +$XFS_IO_PROG -c "cowextsize $((blksz * 128))" -c stat $file1 >> $seqres.full > > + > > +echo "Fragment FS" > > +$XFS_IO_PROG -f -c "pwrite 0 $((blksz * 512))" $fragmentedfile >> $seqres.full > > +sync > > +$here/src/punch-alternating $fragmentedfile > > + > > +echo "Allocate block sized extent from now onwards" > > +_test_inject_error bmap_alloc_minlen_extent 1 > > + > > +echo "Create big delalloc extent in CoW fork" > > +$XFS_IO_PROG -c "pwrite 0 $blksz" $file1 >> $seqres.full > > + > > +sync > > + > > +$XFS_IO_PROG -c 'bmap -elpv' -c 'bmap -celpv' $file1 >> $seqres.full > > The "-c" option might get: > > $ xfs_io -c "bmap -celpv" testfile > xfs_io: xfsctl(XFS_IOC_GETBMAPX) iflags=0x28 ["testfile"]: Invalid argument > > It will break the golden image, can we redirect stderr to $seqres.full, > as it's just for debug? If you agree, I can help to change that by adding > "2>&1" at the end. Or you hope to deal with it by other method? That's fine, I don't need the stderr output. "&>> $seqres.full" works just as well. --D > Thanks, > Zorro > > > > + > > +echo "Direct I/O write at offset 3FSB" > > +$XFS_IO_PROG -d -c "pwrite $((blksz * 3)) $((blksz * 2))" $file1 >> $seqres.full > > + > > +# success, all done > > +status=0 > > +exit > > diff --git a/tests/xfs/1923.out b/tests/xfs/1923.out > > new file mode 100644 > > index 0000000000..a0553cf3ee > > --- /dev/null > > +++ b/tests/xfs/1923.out > > @@ -0,0 +1,8 @@ > > +QA output created by 1923 > > +Create source file > > +Create Reflinked file > > +Set cowextsize > > +Fragment FS > > +Allocate block sized extent from now onwards > > +Create big delalloc extent in CoW fork > > +Direct I/O write at offset 3FSB > > > >