Return-Path: Received: from mail-lj1-f196.google.com ([209.85.208.196]:37785 "EHLO mail-lj1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725799AbeK2Hv6 (ORCPT ); Thu, 29 Nov 2018 02:51:58 -0500 Received: by mail-lj1-f196.google.com with SMTP id e5-v6so24723198lja.4 for ; Wed, 28 Nov 2018 12:49:02 -0800 (PST) From: Artem Blagodarenko To: linux-ext4@vger.kernel.org Cc: adilger.kernel@dilger.ca, alexey.lyashkov@gmail.com Subject: [PATCH v2] ext2fs: don't read group descriptors during e2label Date: Wed, 28 Nov 2018 23:48:40 +0300 Message-Id: <20181128204840.4544-1-artem.blagodarenko@gmail.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: tune2fs is used to make e2label duties. ext2fs_open2() reads group descriptors which are not used during disk label obtaining, but takes a lot of time on large partitions. This patch change ext2fs_open2(), so only initialized superblock is returned. without block descriptors. This save time dramatically. Cray-bug-id: LUS-5777 Signed-off-by: Artem Blagodarenko --- lib/ext2fs/ext2fs.h | 1 + lib/ext2fs/openfs.c | 22 +++++++++++++++++++--- misc/tune2fs.c | 7 ++++++- 3 files changed, 26 insertions(+), 4 deletions(-) diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h index 5b87d395..2abb6f76 100644 --- a/lib/ext2fs/ext2fs.h +++ b/lib/ext2fs/ext2fs.h @@ -204,6 +204,7 @@ typedef struct ext2_file *ext2_file_t; #define EXT2_FLAG_IGNORE_CSUM_ERRORS 0x200000 #define EXT2_FLAG_SHARE_DUP 0x400000 #define EXT2_FLAG_IGNORE_SB_ERRORS 0x800000 +#define EXT2_FLAG_JOURNAL_ONLY 0x1000000 /* * Special flag in the ext2 inode i_flag field that means that this is diff --git a/lib/ext2fs/openfs.c b/lib/ext2fs/openfs.c index 85d73e2a..af671070 100644 --- a/lib/ext2fs/openfs.c +++ b/lib/ext2fs/openfs.c @@ -135,6 +135,7 @@ errcode_t ext2fs_open2(const char *name, const char *io_options, int j; #endif char *time_env; + unsigned long enough_desc_blocks; EXT2_CHECK_MAGIC(manager, EXT2_ET_MAGIC_IO_MANAGER); @@ -440,12 +441,23 @@ errcode_t ext2fs_open2(const char *name, const char *io_options, dest += fs->blocksize*first_meta_bg; } - for (i = first_meta_bg ; i < fs->desc_blocks; i++) { + /* + * Need superblock and journal inode only. Do not read + * met_bg group blocks if journal inode group already loaded + */ + if (flags & EXT2_FLAG_JOURNAL_ONLY) + enough_desc_blocks = + fs->super->s_journal_inum / + EXT2_INODES_PER_GROUP(fs->super) + 1; + else + enough_desc_blocks = fs->desc_blocks; + + for (i = first_meta_bg; i < enough_desc_blocks; i++) { blk = ext2fs_descriptor_block_loc2(fs, group_block, i); io_channel_cache_readahead(fs->io, blk, 1); } - for (i=first_meta_bg ; i < fs->desc_blocks; i++) { + for (i = first_meta_bg; i < enough_desc_blocks; i++) { blk = ext2fs_descriptor_block_loc2(fs, group_block, i); retval = io_channel_read_blk64(fs->io, blk, 1, dest); if (retval) @@ -468,8 +480,12 @@ errcode_t ext2fs_open2(const char *name, const char *io_options, */ if (superblock > 1 && ext2fs_has_group_desc_csum(fs)) { dgrp_t group; + dgrp_t enough_desc_count; + + enough_desc_count = enough_desc_blocks * + EXT2_DESC_PER_BLOCK(fs->super); - for (group = 0; group < fs->group_desc_count; group++) { + for (group = 0; group < enough_desc_count; group++) { ext2fs_bg_flags_clear(fs, group, EXT2_BG_BLOCK_UNINIT); ext2fs_bg_flags_clear(fs, group, EXT2_BG_INODE_UNINIT); ext2fs_bg_itable_unused_set(fs, group, 0); diff --git a/misc/tune2fs.c b/misc/tune2fs.c index cd4057c3..b226fdbf 100644 --- a/misc/tune2fs.c +++ b/misc/tune2fs.c @@ -2882,6 +2882,12 @@ retry_open: /* keep the filesystem struct around to dump MMP data */ open_flag |= EXT2_FLAG_NOFREE_ON_ERROR; + if (print_label || L_flag) { + open_flag |= EXT2_FLAG_JOURNAL_ONLY; + /* don't want metadata to be flushed at close */ + //open_flag &= ~EXT2_FLAG_RW; + } + retval = ext2fs_open2(device_name, io_options, open_flag, 0, 0, io_ptr, &fs); if (retval) { @@ -2999,7 +3005,6 @@ _("Warning: The journal is dirty. You may wish to replay the journal like:\n\n" if ((open_flag & EXT2_FLAG_RW) && !(mount_flags & (EXT2_MF_BUSY | EXT2_MF_MOUNTED)) && ext2fs_has_feature_journal_needs_recovery(fs->super)) { errcode_t err; - printf(_("Recovering journal.\n")); err = ext2fs_run_ext3_journal(&fs); if (err) { -- 2.14.3