From: "Darrick J. Wong" Subject: [PATCH 38/51] mke2fs: Warn if not enabling all the features that metadata_csum wants Date: Sat, 07 Jan 2012 00:36:59 -0800 Message-ID: <20120107083659.25788.49404.stgit@elm3c44.beaverton.ibm.com> References: <20120107083256.25788.41238.stgit@elm3c44.beaverton.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: Sunil Mushran , Amir Goldstein , Andi Kleen , Mingming Cao , Joel Becker , linux-ext4@vger.kernel.org, Coly Li To: Andreas Dilger , Theodore Tso , "Darrick J. Wong" Return-path: Received: from e34.co.us.ibm.com ([32.97.110.152]:36767 "EHLO e34.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751732Ab2AGIhF (ORCPT ); Sat, 7 Jan 2012 03:37:05 -0500 Received: from /spool/local by e34.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Sat, 7 Jan 2012 01:37:05 -0700 Received: from d03av01.boulder.ibm.com (d03av01.boulder.ibm.com [9.17.195.167]) by d03relay01.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q078b28D105080 for ; Sat, 7 Jan 2012 01:37:02 -0700 Received: from d03av01.boulder.ibm.com (loopback [127.0.0.1]) by d03av01.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q078b00g032056 for ; Sat, 7 Jan 2012 01:37:02 -0700 In-Reply-To: <20120107083256.25788.41238.stgit@elm3c44.beaverton.ibm.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: There are some features (gdt_csum, 64bit, bg_use_meta_csum) that help metadata_csum to work optimally. Print a warning if the user tries to create a filesystem without those features. Signed-off-by: Darrick J. Wong --- misc/mke2fs.c | 35 ++++++++++++++++++++++++++++++++++- 1 files changed, 34 insertions(+), 1 deletions(-) diff --git a/misc/mke2fs.c b/misc/mke2fs.c index 14c047a..80218bd 100644 --- a/misc/mke2fs.c +++ b/misc/mke2fs.c @@ -884,7 +884,8 @@ static __u32 ok_features[3] = { EXT2_FEATURE_INCOMPAT_META_BG| EXT4_FEATURE_INCOMPAT_FLEX_BG| EXT4_FEATURE_INCOMPAT_MMP | - EXT4_FEATURE_INCOMPAT_64BIT, + EXT4_FEATURE_INCOMPAT_64BIT | + EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM, /* R/O compat */ EXT2_FEATURE_RO_COMPAT_LARGE_FILE| EXT4_FEATURE_RO_COMPAT_HUGE_FILE| @@ -2298,6 +2299,38 @@ int main (int argc, char *argv[]) exit(1); } + /* Check the user's mkfs options for metadata checksumming */ + if (!quiet && + EXT2_HAS_RO_COMPAT_FEATURE(fs->super, + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) { + if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super, + EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) + printf(_("Group descriptor checksums " + "are not enabled. This reduces the " + "coverage of metadata checksumming. " + "Pass -O uninit_bg to rectify.\n")); + if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super, + EXT4_FEATURE_RO_COMPAT_GDT_CSUM) && + !EXT2_HAS_INCOMPAT_FEATURE(fs->super, + EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM)) + printf(_("Group descriptor checksums will not use " + "the faster metadata_checksum algorithm. " + "Pass -O bg_use_meta_csum to rectify.\n")); + if (!EXT2_HAS_INCOMPAT_FEATURE(fs->super, + EXT3_FEATURE_INCOMPAT_EXTENTS)) + printf(_("Extents are not enabled. The file extent " + "tree can be checksummed, whereas block maps " + "cannot. Not enabling extents reduces the " + "coverage of metadata checksumming. " + "Pass -O extents to rectify.\n")); + if (!EXT2_HAS_INCOMPAT_FEATURE(fs->super, + EXT4_FEATURE_INCOMPAT_64BIT)) + printf(_("64-bit filesystem support is not " + "enabled. The larger fields afforded by " + "this feature enable full-strength " + "checksumming. Pass -O 64bit to rectify.\n")); + } + /* Can't undo discard ... */ if (!noaction && discard && (io_ptr != undo_io_manager)) { retval = mke2fs_discard_device(fs);