From: "Darrick J. Wong" Subject: [PATCH 18/34] libext2fs: file IO routines should handle uninit blocks Date: Sat, 13 Sep 2014 15:13:12 -0700 Message-ID: <20140913221312.13646.65526.stgit@birch.djwong.org> References: <20140913221112.13646.3873.stgit@birch.djwong.org> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: linux-ext4@vger.kernel.org To: tytso@mit.edu, darrick.wong@oracle.com Return-path: Received: from userp1040.oracle.com ([156.151.31.81]:32370 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752335AbaIMWNR (ORCPT ); Sat, 13 Sep 2014 18:13:17 -0400 In-Reply-To: <20140913221112.13646.3873.stgit@birch.djwong.org> Sender: linux-ext4-owner@vger.kernel.org List-ID: The file IO routines do not handle uninit blocks at all. The read method should check for the uninit flag and return a buffer of zeroes, and the write routine should convert unwritten extents. Signed-off-by: Darrick J. Wong --- lib/ext2fs/fileio.c | 24 ++++++++++++++++++++++-- tests/f_uninit_cat/expect | Bin tests/f_uninit_cat/image.gz | Bin tests/f_uninit_cat/name | 1 + tests/f_uninit_cat/script | 37 +++++++++++++++++++++++++++++++++++++ 5 files changed, 60 insertions(+), 2 deletions(-) create mode 100644 tests/f_uninit_cat/expect create mode 100644 tests/f_uninit_cat/image.gz create mode 100644 tests/f_uninit_cat/name create mode 100755 tests/f_uninit_cat/script diff --git a/lib/ext2fs/fileio.c b/lib/ext2fs/fileio.c index 1d5032a..d0a05d6 100644 --- a/lib/ext2fs/fileio.c +++ b/lib/ext2fs/fileio.c @@ -123,6 +123,8 @@ errcode_t ext2fs_file_flush(ext2_file_t file) { errcode_t retval; ext2_filsys fs; + int ret_flags; + blk64_t dontcare; EXT2_CHECK_MAGIC(file, EXT2_ET_MAGIC_EXT2_FILE); fs = file->fs; @@ -131,6 +133,22 @@ errcode_t ext2fs_file_flush(ext2_file_t file) !(file->flags & EXT2_FILE_BUF_DIRTY)) return 0; + /* Is this an uninit block? */ + if (file->physblock && file->inode.i_flags & EXT4_EXTENTS_FL) { + retval = ext2fs_bmap2(fs, file->ino, &file->inode, BMAP_BUFFER, + 0, file->blockno, &ret_flags, &dontcare); + if (retval) + return retval; + if (ret_flags & BMAP_RET_UNINIT) { + retval = ext2fs_bmap2(fs, file->ino, &file->inode, + BMAP_BUFFER, BMAP_SET, + file->blockno, 0, + &file->physblock); + if (retval) + return retval; + } + } + /* * OK, the physical block hasn't been allocated yet. * Allocate it. @@ -185,15 +203,17 @@ static errcode_t load_buffer(ext2_file_t file, int dontfill) { ext2_filsys fs = file->fs; errcode_t retval; + int ret_flags; if (!(file->flags & EXT2_FILE_BUF_VALID)) { retval = ext2fs_bmap2(fs, file->ino, &file->inode, - BMAP_BUFFER, 0, file->blockno, 0, + BMAP_BUFFER, 0, file->blockno, &ret_flags, &file->physblock); if (retval) return retval; if (!dontfill) { - if (file->physblock) { + if (file->physblock && + !(ret_flags & BMAP_RET_UNINIT)) { retval = io_channel_read_blk64(fs->io, file->physblock, 1, file->buf); diff --git a/tests/f_uninit_cat/expect b/tests/f_uninit_cat/expect new file mode 100644 index 0000000000000000000000000000000000000000..0c0a5cf84cc58483ca33e257259607e4ca54ebbe GIT binary patch literal 3623 zcmeH{v2KGf5Qa1J6t`4rrKVs4QNvoLQ-&;^E5{tf3b8An9fdx94LB%6-ypu_bol%I zbN}EyCjwT%#}UOzsurZuHPR~_IxSAVb5#S$U!-I|p!pqIOM}8{(*s%KgmnfdX!S27 zv{Igz7is&6EABXh4H{GeL1?FJuq*F~)@b(w#|E(61l{JQn-!~Bkq1RSFzev!`&hG6*uNSB@QW^D#ROsk a51YU>R!kr!@URIy?86rqj|s#C7RevINPdd| literal 0 HcmV?d00001 diff --git a/tests/f_uninit_cat/image.gz b/tests/f_uninit_cat/image.gz new file mode 100644 index 0000000000000000000000000000000000000000..d2ae66cb35f93dd4022e85f8667365487a7b24ea GIT binary patch literal 1553 zcmb2|=3wBo77AfvetUOgws4>X!-w+e5!ulJUCtMqn*6x7X0!`+M-&JY2D}M!S)+8+ zDVJ6IMapY?1&f!@9@sy4qUHCltf(-cFi@sME%1$ zf6YFjs>qO9YUaC2aZcCS-(DQb8_$NVE7;Mo<=)q*|3~ghM6S5L{?7@i*S^PYuMLg< z{yO)bMDN+#HZAQNWmni(e$ISz=k4?0&B2S~=hf!a%c;LRqnoqOeE0R(Td}i${(5!v zN9*zV=lkXUet4HAR(*B4`0223$*Xyed2c)RXUFctq3v?k4*osNhJB`=>Q$cfF5YY) zq&Igc;>t5Mgf0ATh%=q$g`@RWJoj2;Pd;ar6z(>h_e;2CHpSyp1 zK~2@ae|Oey(P??=HSMlJ&Y}8++jalfhj#s8_ga)C-tdS0iM_&q#-IEr>K*6Fj_h@afy|?67dd1pb`uxmif2pqt{Qt!?S^L#|zi0nX zFI}X(^4;uQx9mT!qeB0OhF!1kR=hH+G@ zsFGV7C4lT;jqS<~nYIjGr#U#DKDAdsmKtS`hQMeD44Duxd!&D1J4-kNg8%~n1^y`^ literal 0 HcmV?d00001 diff --git a/tests/f_uninit_cat/name b/tests/f_uninit_cat/name new file mode 100644 index 0000000..f6b5674 --- /dev/null +++ b/tests/f_uninit_cat/name @@ -0,0 +1 @@ +cat a file with uninit blocks diff --git a/tests/f_uninit_cat/script b/tests/f_uninit_cat/script new file mode 100755 index 0000000..11dbb6e --- /dev/null +++ b/tests/f_uninit_cat/script @@ -0,0 +1,37 @@ +#!/bin/bash + +if test -x $DEBUGFS_EXE; then +FSCK_OPT=-fy +IMAGE=$test_dir/image.gz + +gzip -d < $IMAGE > $TMPFILE +#e2label $TMPFILE test_filesys + +# Run fsck to fix things? +EXP=$test_dir/expect +OUT=$test_name.log +rm -rf $test_name.failed $test_name.ok + +$FSCK $FSCK_OPT -N test_filesys $TMPFILE 2>&1 | sed -f $cmd_dir/filter.sed > $OUT +echo "Exit status is $?" >> $OUT + +echo "debugfs cat uninit file" >> $OUT +echo "ex /a" > $TMPFILE.cmd +echo "cat /a" >> $TMPFILE.cmd +$DEBUGFS_EXE -w $TMPFILE -f $TMPFILE.cmd >> $OUT.new 2>&1 +echo >> $OUT.new +sed -f $cmd_dir/filter.sed < $OUT.new >> $OUT +rm -rf $OUT.new $TMPFILE + +# Figure out what happened +if cmp -s $EXP $OUT; then + echo "$test_name: $test_description: ok" + touch $test_name.ok +else + echo "$test_name: $test_description: failed" + diff -u $EXP $OUT >> $test_name.failed +fi +unset EXP OUT FSCK_OPT IMAGE +else #if test -a -x $DEBUGFS_EXE; then + echo "$test_name: $test_description: skipped" +fi