From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Darrick J. Wong" Subject: [PATCH 00/12] e2fsprogs: misc fixes and cleanups; save checksum seeds Date: Mon, 12 Oct 2015 14:56:29 -0700 Message-ID: <20151012215629.29065.24418.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]:39829 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751950AbbJLV4e (ORCPT ); Mon, 12 Oct 2015 17:56:34 -0400 Sender: linux-ext4-owner@vger.kernel.org List-ID: Hi all, Here's a short patch series that rolls up all my pending fixes for assorted minor problems with e2fsprogs. It then replaces all the open coded feature flag functions with a series of helper functions; and finally it introduces the "metdata_csum_seed" feature which decouples the metadata block checksums from the FS UUID so that said UUID can be changed while the FS is mounted. Patches 1-2 fix an incorrect overhead calculation in mke2fs when formatting with meta_bg that prevented formatting devices larger than 256TB; and teaches mke2fs to enable meta_bg whenever the group descriptor blocks overflow a block group. This makes it possible to format ext4 on multi-petabyte block devices, albeit at a SEVERE overhead cost. Patches 3-7 replace open-coded feature flag manipulation code with helper functions. I've hand-checked all the changes to ensure that they are correct. Patches 8-12 introduces the metadata_csum_seed feature, which saves the first component of metadata block checksums (specifically, the value of crc32c(~0, FS_UUID)) in the superblock. This enables the administrator to change the UUID on a mounted metadata_csum filesystem. The patchset should apply cleanly against the -next branch as of 29 September. Comments and questions are, as always, welcome. --D