From: Azat Khuzhin Subject: [PATCH 4/4 v3] tune2fs: update journal users while updating fs UUID (with external journal) Date: Mon, 28 Jul 2014 11:43:25 +0400 Message-ID: <1406533405-6899-5-git-send-email-a3at.mail@gmail.com> References: <1406533405-6899-1-git-send-email-a3at.mail@gmail.com> Cc: tytso@mit.edu, darrick.wong@oracle.com, adilger@dilger.ca, Azat Khuzhin To: linux-ext4@vger.kernel.org Return-path: Received: from mail-la0-f43.google.com ([209.85.215.43]:53847 "EHLO mail-la0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750952AbaG1HoG (ORCPT ); Mon, 28 Jul 2014 03:44:06 -0400 Received: by mail-la0-f43.google.com with SMTP id hr17so5131921lab.16 for ; Mon, 28 Jul 2014 00:44:04 -0700 (PDT) In-Reply-To: <1406533405-6899-1-git-send-email-a3at.mail@gmail.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: When we have fs with external journal device, and updating it's UUID, we should update UUID in users list for that external journal device. Before: $ tune2fs -U clear /tmp/dev tune2fs 1.42.10 (18-May-2014) $ dumpe2fs /tmp/dev | fgrep UUID dumpe2fs 1.42.10 (18-May-2014) Filesystem UUID: Journal UUID: da1f2ed0-60f6-aaaa-92fd-738701418523 $ dumpe2fs /tmp/journal | fgrep users -A10 dumpe2fs 1.42.10 (18-May-2014) Journal number of users: 2 Journal users: 0707762d-638e-4bc6-944e-ae8ee7a3359e 0ad849df-1041-4f0a-b1c1-2f949d6a1e37 After: $ sudo tune2fs -U clear /tmp/dev tune2fs 1.43-WIP (18-May-2014) $ dumpe2fs /tmp/dev | fgrep UUID dumpe2fs 1.42.10 (18-May-2014) Filesystem UUID: Journal UUID: da1f2ed0-60f6-aaaa-92fd-738701418523 $ dumpe2fs /tmp/journal | fgrep users -A10 dumpe2fs 1.42.10 (18-May-2014) Journal number of users: 2 Journal users: 0707762d-638e-4bc6-944e-ae8ee7a3359e 00000000-0000-0000-0000-000000000000 Also add some consts to avoid *magic numbers*: - UUID_STR_SIZE - UUID_SIZE - JFS_USERS_MAX - JFS_USERS_SIZE Proposed-by: Andreas Dilger Signed-off-by: Azat Khuzhin --- lib/ext2fs/ext2fs.h | 2 ++ lib/ext2fs/kernel-jbd.h | 6 +++- misc/tune2fs.c | 90 +++++++++++++++++++++++++++++++++++++++++++++---- misc/uuidd.c | 3 +- 4 files changed, 93 insertions(+), 8 deletions(-) diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h index ab57534..d3a34d5 100644 --- a/lib/ext2fs/ext2fs.h +++ b/lib/ext2fs/ext2fs.h @@ -39,6 +39,8 @@ extern "C" { #define SUPERBLOCK_OFFSET 1024 #define SUPERBLOCK_SIZE 1024 +#define UUID_STR_SIZE 37 + /* * The last ext2fs revision level that this version of the library is * able to support. diff --git a/lib/ext2fs/kernel-jbd.h b/lib/ext2fs/kernel-jbd.h index 059bf8f..2baae73 100644 --- a/lib/ext2fs/kernel-jbd.h +++ b/lib/ext2fs/kernel-jbd.h @@ -164,6 +164,9 @@ typedef struct journal_revoke_header_s #define JFS_FLAG_LAST_TAG 8 /* last tag in this descriptor block */ +#define UUID_SIZE 16 +#define JFS_USERS_MAX 48 +#define JFS_USERS_SIZE (UUID_SIZE * JFS_USERS_MAX) /* * The journal superblock. All fields are in big-endian byte order. */ @@ -208,7 +211,8 @@ typedef struct journal_superblock_s __u32 s_padding[44]; /* 0x0100 */ - __u8 s_users[16*48]; /* ids of all fs'es sharing the log */ + __u8 s_users[JFS_USERS_SIZE]; /* ids of all fs'es sharing the log */ + /* 0x0400 */ } journal_superblock_t; diff --git a/misc/tune2fs.c b/misc/tune2fs.c index 74e57ae..0c1feb1 100644 --- a/misc/tune2fs.c +++ b/misc/tune2fs.c @@ -207,6 +207,18 @@ static int get_journal_sb(ext2_filsys jfs, char buf[SUPERBLOCK_SIZE]) return 0; } +static void * +journal_user(char uuid[UUID_SIZE], char s_users[JFS_USERS_SIZE], int nr_users) +{ + int i; + for (i = 0; i < nr_users; i++) { + if (memcmp(uuid, &s_users[i * UUID_SIZE], UUID_SIZE) == 0) + return &s_users[i * UUID_SIZE]; + } + + return NULL; +} + /* * Remove an external journal from the filesystem */ @@ -261,11 +273,8 @@ static int remove_journal_device(ext2_filsys fs) jsb = (journal_superblock_t *) buf; /* Find the filesystem UUID */ nr_users = ntohl(jsb->s_nr_users); - for (i = 0; i < nr_users; i++) { - if (memcmp(fs->super->s_uuid, &jsb->s_users[i * 16], 16) == 0) - break; - } - if (i >= nr_users) { + + if (!journal_user(fs->super->s_uuid, jsb->s_users, nr_users)) { fputs(_("Filesystem's UUID not found on journal device.\n"), stderr); commit_remove_journal = 1; @@ -1915,6 +1924,68 @@ static int tune2fs_setup_tdb(const char *name, io_manager *io_ptr) return retval; } +int +fs_update_journal_user(struct ext2_super_block *sb, char old_uuid[UUID_SIZE]) +{ + int retval, nr_users, start; + journal_superblock_t *jsb; + ext2_filsys jfs; + char *j_uuid, *journal_path; + char uuid[UUID_STR_SIZE]; + char buf[SUPERBLOCK_SIZE]; + + if (!(sb->s_feature_compat & EXT3_FEATURE_COMPAT_HAS_JOURNAL) || + uuid_is_null(sb->s_journal_uuid)) + return 0; + + uuid_unparse(sb->s_journal_uuid, uuid); + journal_path = blkid_get_devname(NULL, "UUID", uuid); + if (!journal_path) + return 0; + + retval = ext2fs_open2(journal_path, io_options, + EXT2_FLAG_JOURNAL_DEV_OK | EXT2_FLAG_RW, + 0, 0, unix_io_manager, &jfs); + if (retval) { + com_err(program_name, retval, + _("while trying to open %s"), + journal_path); + return retval; + } + + if ((retval = get_journal_sb(jfs, buf))) { + if (retval == EXT2_ET_UNSUPP_FEATURE) + fprintf(stderr, _("%s is not a journal device.\n"), + journal_path); + return retval; + } + + jsb = (journal_superblock_t *) buf; + /* Find the filesystem UUID */ + nr_users = ntohl(jsb->s_nr_users); + + if (!(j_uuid = journal_user(old_uuid, jsb->s_users, nr_users))) { + fputs(_("Filesystem's UUID not found on journal device.\n"), + stderr); + return EXT2_ET_LOAD_EXT_JOURNAL; + } + + memcpy(j_uuid, sb->s_uuid, UUID_SIZE); + + start = ext2fs_journal_sb_start(jfs->blocksize); + /* Write back the journal superblock */ + if ((retval = io_channel_write_blk64(jfs->io, start, + -SUPERBLOCK_SIZE, buf))) { + com_err(program_name, retval, + "while writing journal superblock."); + return retval; + } + + ext2fs_close(jfs); + + return 0; +} + int main(int argc, char **argv) { errcode_t retval; @@ -2203,6 +2274,7 @@ retry_open: int set_csum = 0; dgrp_t i; char buf[SUPERBLOCK_SIZE]; + char old_uuid[UUID_SIZE]; if (sb->s_feature_ro_compat & EXT4_FEATURE_RO_COMPAT_GDT_CSUM) { @@ -2230,6 +2302,8 @@ retry_open: if (i >= fs->group_desc_count) set_csum = 1; } + + memcpy(old_uuid, sb->s_uuid, UUID_SIZE); if ((strcasecmp(new_UUID, "null") == 0) || (strcasecmp(new_UUID, "clear") == 0)) { uuid_clear(sb->s_uuid); @@ -2264,9 +2338,13 @@ retry_open: goto closefs; } else if (rc != EXT2_ET_UNSUPP_FEATURE) goto closefs; - else + else { rc = 0; /** Reset rc to avoid ext2fs_mmp_stop() */ + if ((rc = fs_update_journal_user(sb, old_uuid))) + goto closefs; + } + ext2fs_mark_super_dirty(fs); } if (I_flag) { diff --git a/misc/uuidd.c b/misc/uuidd.c index 5a53138..02ca6be 100644 --- a/misc/uuidd.c +++ b/misc/uuidd.c @@ -36,6 +36,7 @@ extern int optind; #include "uuid/uuid.h" #include "uuid/uuidd.h" #include "nls-enable.h" +#include "ext2fs/ext2fs.h" #ifdef __GNUC__ #define CODE_ATTR(x) __attribute__(x) @@ -236,7 +237,7 @@ static void server_loop(const char *socket_path, const char *pidfile_path, uuid_t uu; mode_t save_umask; char reply_buf[1024], *cp; - char op, str[37]; + char op, str[UUID_STR_SIZE]; int i, s, ns, len, num; int fd_pidfile, ret; -- 2.0.1