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charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net On 2/7/25 05:47, Jaegeuk Kim wrote: > On 02/06, Chao Yu wrote: >> F2FS-fs (dm-59): checkpoint=enable has some unwritten data. >> >> ------------[ cut here ]------------ >> WARNING: CPU: 6 PID: 8013 at fs/quota/dquot.c:691 dquot_writeback_dquots+0x2fc/0x308 >> pc : dquot_writeback_dquots+0x2fc/0x308 >> lr : f2fs_quota_sync+0xcc/0x1c4 >> Call trace: >> dquot_writeback_dquots+0x2fc/0x308 >> f2fs_quota_sync+0xcc/0x1c4 >> f2fs_write_checkpoint+0x3d4/0x9b0 >> f2fs_issue_checkpoint+0x1bc/0x2c0 >> f2fs_sync_fs+0x54/0x150 >> f2fs_do_sync_file+0x2f8/0x814 >> __f2fs_ioctl+0x1960/0x3244 >> f2fs_ioctl+0x54/0xe0 >> __arm64_sys_ioctl+0xa8/0xe4 >> invoke_syscall+0x58/0x114 >> >> checkpoint and f2fs_remount may race as below, resulting triggering warning >> in dquot_writeback_dquots(). >> >> atomic write remount >> - do_remount >> - down_write(&sb->s_umount); >> - f2fs_remount >> - ioctl >> - f2fs_do_sync_file >> - f2fs_sync_fs >> - f2fs_write_checkpoint >> - block_operations >> - locked = down_read_trylock(&sbi->sb->s_umount) >> : fail to lock due to the write lock was held by remount >> - up_write(&sb->s_umount); >> - f2fs_quota_sync >> - dquot_writeback_dquots >> - WARN_ON_ONCE(!rwsem_is_locked(&sb->s_umount)) >> : trigger warning because s_umount lock was unlocked by remount >> >> If checkpoint comes from mount/umount/remount/freeze/quotactl, caller of >> checkpoint has already held s_umount lock, calling dquot_writeback_dquots() >> in the context should be safe. >> >> So let's record task to sbi->umount_lock_holder, so that checkpoint can >> know whether the lock has held in the context or not by checking current >> w/ it. >> >> In addition, in order to misrepresent caller of checkpoint, we should not >> allow to trigger async checkpoint for those callers: mount/umount/remount/ >> freeze/quotactl. >> >> Fixes: af033b2aa8a8 ("f2fs: guarantee journalled quota data by checkpoint") >> Signed-off-by: Chao Yu >> --- >> fs/f2fs/checkpoint.c | 17 ++++++++----- >> fs/f2fs/f2fs.h | 3 ++- >> fs/f2fs/super.c | 59 +++++++++++++++++++++++++++++++++++--------- >> 3 files changed, 60 insertions(+), 19 deletions(-) >> >> diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c >> index efda9a022981..baff639ac0c4 100644 >> --- a/fs/f2fs/checkpoint.c >> +++ b/fs/f2fs/checkpoint.c >> @@ -1237,7 +1237,8 @@ static int block_operations(struct f2fs_sb_info *sbi) >> retry_flush_quotas: >> f2fs_lock_all(sbi); >> if (__need_flush_quota(sbi)) { >> - int locked; >> + bool need_lock = sbi->umount_lock_holder != current; >> + bool locked = false; > > I removed the above unnecessary locked. > >> >> if (++cnt > DEFAULT_RETRY_QUOTA_FLUSH_COUNT) { >> set_sbi_flag(sbi, SBI_QUOTA_SKIP_FLUSH); >> @@ -1246,10 +1247,13 @@ static int block_operations(struct f2fs_sb_info *sbi) >> } >> f2fs_unlock_all(sbi); >> >> - /* only failed during mount/umount/freeze/quotactl */ >> - locked = down_read_trylock(&sbi->sb->s_umount); >> - f2fs_quota_sync(sbi->sb, -1); >> - if (locked) >> + /* don't grab s_umount lock during mount/umount/remount/freeze/quotactl */ >> + if (need_lock && !down_read_trylock(&sbi->sb->s_umount)) { >> + cond_resched(); >> + goto retry_flush_quotas; >> + } >> + f2fs_do_quota_sync(sbi->sb, -1); >> + if (need_lock) >> up_read(&sbi->sb->s_umount); >> cond_resched(); >> goto retry_flush_quotas; > > Modified to: > /* don't grab s_umount lock during mount/umount/remount/freeze/quotactl */ > if (!need_lock) { > f2fs_do_quota_sync(sbi->sb, -1); > } else if (down_read_trylock(&sbi->sb->s_umount)) { > f2fs_do_quota_sync(sbi->sb, -1); > up_read(&sbi->sb->s_umount); > } > cond_resched(); > goto retry_flush_quotas; Will update it into v2 anyway, thanks. Thanks, > >> @@ -1867,7 +1871,8 @@ int f2fs_issue_checkpoint(struct f2fs_sb_info *sbi) >> struct cp_control cpc; >> >> cpc.reason = __get_cp_reason(sbi); >> - if (!test_opt(sbi, MERGE_CHECKPOINT) || cpc.reason != CP_SYNC) { >> + if (!test_opt(sbi, MERGE_CHECKPOINT) || cpc.reason != CP_SYNC || >> + sbi->umount_lock_holder == current) { >> int ret; >> >> f2fs_down_write(&sbi->gc_lock); >> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h >> index 62b7fed1514a..7174dea641e9 100644 >> --- a/fs/f2fs/f2fs.h >> +++ b/fs/f2fs/f2fs.h >> @@ -1670,6 +1670,7 @@ struct f2fs_sb_info { >> >> unsigned int nquota_files; /* # of quota sysfile */ >> struct f2fs_rwsem quota_sem; /* blocking cp for flags */ >> + struct task_struct *umount_lock_holder; /* s_umount lock holder */ >> >> /* # of pages, see count_type */ >> atomic_t nr_pages[NR_COUNT_TYPE]; >> @@ -3652,7 +3653,7 @@ int f2fs_inode_dirtied(struct inode *inode, bool sync); >> void f2fs_inode_synced(struct inode *inode); >> int f2fs_dquot_initialize(struct inode *inode); >> int f2fs_enable_quota_files(struct f2fs_sb_info *sbi, bool rdonly); >> -int f2fs_quota_sync(struct super_block *sb, int type); >> +int f2fs_do_quota_sync(struct super_block *sb, int type); >> loff_t max_file_blocks(struct inode *inode); >> void f2fs_quota_off_umount(struct super_block *sb); >> void f2fs_save_errors(struct f2fs_sb_info *sbi, unsigned char flag); >> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c >> index ef639a6d82e5..cb9d7b6fa3ad 100644 >> --- a/fs/f2fs/super.c >> +++ b/fs/f2fs/super.c >> @@ -1740,22 +1740,28 @@ int f2fs_sync_fs(struct super_block *sb, int sync) >> >> static int f2fs_freeze(struct super_block *sb) >> { >> + struct f2fs_sb_info *sbi = F2FS_SB(sb); >> + >> if (f2fs_readonly(sb)) >> return 0; >> >> /* IO error happened before */ >> - if (unlikely(f2fs_cp_error(F2FS_SB(sb)))) >> + if (unlikely(f2fs_cp_error(sbi))) >> return -EIO; >> >> /* must be clean, since sync_filesystem() was already called */ >> - if (is_sbi_flag_set(F2FS_SB(sb), SBI_IS_DIRTY)) >> + if (is_sbi_flag_set(sbi, SBI_IS_DIRTY)) >> return -EINVAL; >> >> + sbi->umount_lock_holder = current; >> + >> /* Let's flush checkpoints and stop the thread. */ >> - f2fs_flush_ckpt_thread(F2FS_SB(sb)); >> + f2fs_flush_ckpt_thread(sbi); >> + >> + sbi->umount_lock_holder = NULL; >> >> /* to avoid deadlock on f2fs_evict_inode->SB_FREEZE_FS */ >> - set_sbi_flag(F2FS_SB(sb), SBI_IS_FREEZING); >> + set_sbi_flag(sbi, SBI_IS_FREEZING); >> return 0; >> } >> >> @@ -2332,6 +2338,8 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data) >> org_mount_opt = sbi->mount_opt; >> old_sb_flags = sb->s_flags; >> >> + sbi->umount_lock_holder = current; >> + >> #ifdef CONFIG_QUOTA >> org_mount_opt.s_jquota_fmt = F2FS_OPTION(sbi).s_jquota_fmt; >> for (i = 0; i < MAXQUOTAS; i++) { >> @@ -2555,6 +2563,8 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data) >> >> limit_reserve_root(sbi); >> *flags = (*flags & ~SB_LAZYTIME) | (sb->s_flags & SB_LAZYTIME); >> + >> + sbi->umount_lock_holder = NULL; >> return 0; >> restore_checkpoint: >> if (need_enable_checkpoint) { >> @@ -2595,6 +2605,8 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data) >> #endif >> sbi->mount_opt = org_mount_opt; >> sb->s_flags = old_sb_flags; >> + >> + sbi->umount_lock_holder = NULL; >> return err; >> } >> >> @@ -2911,7 +2923,7 @@ static int f2fs_quota_sync_file(struct f2fs_sb_info *sbi, int type) >> return ret; >> } >> >> -int f2fs_quota_sync(struct super_block *sb, int type) >> +int f2fs_do_quota_sync(struct super_block *sb, int type) >> { >> struct f2fs_sb_info *sbi = F2FS_SB(sb); >> struct quota_info *dqopt = sb_dqopt(sb); >> @@ -2959,6 +2971,16 @@ int f2fs_quota_sync(struct super_block *sb, int type) >> return ret; >> } >> >> +static int f2fs_quota_sync(struct super_block *sb, int type) >> +{ >> + int ret; >> + >> + F2FS_SB(sb)->umount_lock_holder = current; >> + ret = f2fs_do_quota_sync(sb, type); >> + F2FS_SB(sb)->umount_lock_holder = NULL; >> + return ret; >> +} >> + >> static int f2fs_quota_on(struct super_block *sb, int type, int format_id, >> const struct path *path) >> { >> @@ -2974,30 +2996,33 @@ static int f2fs_quota_on(struct super_block *sb, int type, int format_id, >> if (path->dentry->d_sb != sb) >> return -EXDEV; >> >> - err = f2fs_quota_sync(sb, type); >> + F2FS_SB(sb)->umount_lock_holder = current; >> + >> + err = f2fs_do_quota_sync(sb, type); >> if (err) >> - return err; >> + goto out; >> >> inode = d_inode(path->dentry); >> >> err = filemap_fdatawrite(inode->i_mapping); >> if (err) >> - return err; >> + goto out; >> >> err = filemap_fdatawait(inode->i_mapping); >> if (err) >> - return err; >> + goto out; >> >> err = dquot_quota_on(sb, type, format_id, path); >> if (err) >> - return err; >> + goto out; >> >> inode_lock(inode); >> F2FS_I(inode)->i_flags |= F2FS_QUOTA_DEFAULT_FL; >> f2fs_set_inode_flags(inode); >> inode_unlock(inode); >> f2fs_mark_inode_dirty_sync(inode, false); >> - >> +out: >> + F2FS_SB(sb)->umount_lock_holder = NULL; >> return 0; >> } >> >> @@ -3009,7 +3034,7 @@ static int __f2fs_quota_off(struct super_block *sb, int type) >> if (!inode || !igrab(inode)) >> return dquot_quota_off(sb, type); >> >> - err = f2fs_quota_sync(sb, type); >> + err = f2fs_do_quota_sync(sb, type); >> if (err) >> goto out_put; >> >> @@ -3032,6 +3057,8 @@ static int f2fs_quota_off(struct super_block *sb, int type) >> struct f2fs_sb_info *sbi = F2FS_SB(sb); >> int err; >> >> + F2FS_SB(sb)->umount_lock_holder = current; >> + >> err = __f2fs_quota_off(sb, type); >> >> /* >> @@ -3041,6 +3068,9 @@ static int f2fs_quota_off(struct super_block *sb, int type) >> */ >> if (is_journalled_quota(sbi)) >> set_sbi_flag(sbi, SBI_QUOTA_NEED_REPAIR); >> + >> + F2FS_SB(sb)->umount_lock_holder = NULL; >> + >> return err; >> } >> >> @@ -4715,6 +4745,7 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent) >> if (err) >> goto free_compress_inode; >> >> + sbi->umount_lock_holder = current; >> #ifdef CONFIG_QUOTA >> /* Enable quota usage during mount */ >> if (f2fs_sb_has_quota_ino(sbi) && !f2fs_readonly(sb)) { >> @@ -4841,6 +4872,8 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent) >> f2fs_update_time(sbi, CP_TIME); >> f2fs_update_time(sbi, REQ_TIME); >> clear_sbi_flag(sbi, SBI_CP_DISABLED_QUICK); >> + >> + sbi->umount_lock_holder = NULL; >> return 0; >> >> sync_free_meta: >> @@ -4945,6 +4978,8 @@ static void kill_f2fs_super(struct super_block *sb) >> struct f2fs_sb_info *sbi = F2FS_SB(sb); >> >> if (sb->s_root) { >> + sbi->umount_lock_holder = current; >> + >> set_sbi_flag(sbi, SBI_IS_CLOSE); >> f2fs_stop_gc_thread(sbi); >> f2fs_stop_discard_thread(sbi); >> -- >> 2.48.1.502.g6dc24dfdaf-goog _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6E2714C6E for ; Fri, 7 Feb 2025 01:49:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; 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Fri, 7 Feb 2025 01:49:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1738892989; bh=IclCJdX+vKplfAJvRmJxScHC9W5RUYHMaSI5s9SMm+w=; h=Date:Cc:Subject:To:References:From:In-Reply-To:From; b=sGd7NYNnlXqNTiGAePfuPwcKA4Hr1dqYpsRe2nOkW5yvY4/B1IKyk6LTPxqEnH+WR 7PkG2i1A+X35UniVBv0lT0Dx82pmqYft2NbBrSV1HmAjDsRsKo+BorJ+f3ZdUFYp/Z lj34aJWfNjJ3zHkVwl0IeEyFM2C1iNw77eASU5ST3D/nUDjE3TQm5TUAWS5f8tEte+ aJWnS2+LobyfErwDE6JN8s1Hm37JIQ9r3KoxrX7+uHvrGbqgv6fbFJbv28ZxmbA7UJ wLTta+jX8UN4V60KjQ/y+sK8Zr+XJXsoInl9Du+Ay1lgHoyboI+ENVMJrPUOc5dWMv H6OUSWHSb1ZXw== Message-ID: <8060c2e9-478a-40fc-afeb-453d83e46ae3@kernel.org> Date: Fri, 7 Feb 2025 09:49:46 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Cc: chao@kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org Subject: Re: [PATCH] f2fs: quota: fix to avoid warning in dquot_writeback_dquots() To: Jaegeuk Kim References: <20250206064451.3088028-1-chao@kernel.org> Content-Language: en-US From: Chao Yu In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 2/7/25 05:47, Jaegeuk Kim wrote: > On 02/06, Chao Yu wrote: >> F2FS-fs (dm-59): checkpoint=enable has some unwritten data. >> >> ------------[ cut here ]------------ >> WARNING: CPU: 6 PID: 8013 at fs/quota/dquot.c:691 dquot_writeback_dquots+0x2fc/0x308 >> pc : dquot_writeback_dquots+0x2fc/0x308 >> lr : f2fs_quota_sync+0xcc/0x1c4 >> Call trace: >> dquot_writeback_dquots+0x2fc/0x308 >> f2fs_quota_sync+0xcc/0x1c4 >> f2fs_write_checkpoint+0x3d4/0x9b0 >> f2fs_issue_checkpoint+0x1bc/0x2c0 >> f2fs_sync_fs+0x54/0x150 >> f2fs_do_sync_file+0x2f8/0x814 >> __f2fs_ioctl+0x1960/0x3244 >> f2fs_ioctl+0x54/0xe0 >> __arm64_sys_ioctl+0xa8/0xe4 >> invoke_syscall+0x58/0x114 >> >> checkpoint and f2fs_remount may race as below, resulting triggering warning >> in dquot_writeback_dquots(). >> >> atomic write remount >> - do_remount >> - down_write(&sb->s_umount); >> - f2fs_remount >> - ioctl >> - f2fs_do_sync_file >> - f2fs_sync_fs >> - f2fs_write_checkpoint >> - block_operations >> - locked = down_read_trylock(&sbi->sb->s_umount) >> : fail to lock due to the write lock was held by remount >> - up_write(&sb->s_umount); >> - f2fs_quota_sync >> - dquot_writeback_dquots >> - WARN_ON_ONCE(!rwsem_is_locked(&sb->s_umount)) >> : trigger warning because s_umount lock was unlocked by remount >> >> If checkpoint comes from mount/umount/remount/freeze/quotactl, caller of >> checkpoint has already held s_umount lock, calling dquot_writeback_dquots() >> in the context should be safe. >> >> So let's record task to sbi->umount_lock_holder, so that checkpoint can >> know whether the lock has held in the context or not by checking current >> w/ it. >> >> In addition, in order to misrepresent caller of checkpoint, we should not >> allow to trigger async checkpoint for those callers: mount/umount/remount/ >> freeze/quotactl. >> >> Fixes: af033b2aa8a8 ("f2fs: guarantee journalled quota data by checkpoint") >> Signed-off-by: Chao Yu >> --- >> fs/f2fs/checkpoint.c | 17 ++++++++----- >> fs/f2fs/f2fs.h | 3 ++- >> fs/f2fs/super.c | 59 +++++++++++++++++++++++++++++++++++--------- >> 3 files changed, 60 insertions(+), 19 deletions(-) >> >> diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c >> index efda9a022981..baff639ac0c4 100644 >> --- a/fs/f2fs/checkpoint.c >> +++ b/fs/f2fs/checkpoint.c >> @@ -1237,7 +1237,8 @@ static int block_operations(struct f2fs_sb_info *sbi) >> retry_flush_quotas: >> f2fs_lock_all(sbi); >> if (__need_flush_quota(sbi)) { >> - int locked; >> + bool need_lock = sbi->umount_lock_holder != current; >> + bool locked = false; > > I removed the above unnecessary locked. > >> >> if (++cnt > DEFAULT_RETRY_QUOTA_FLUSH_COUNT) { >> set_sbi_flag(sbi, SBI_QUOTA_SKIP_FLUSH); >> @@ -1246,10 +1247,13 @@ static int block_operations(struct f2fs_sb_info *sbi) >> } >> f2fs_unlock_all(sbi); >> >> - /* only failed during mount/umount/freeze/quotactl */ >> - locked = down_read_trylock(&sbi->sb->s_umount); >> - f2fs_quota_sync(sbi->sb, -1); >> - if (locked) >> + /* don't grab s_umount lock during mount/umount/remount/freeze/quotactl */ >> + if (need_lock && !down_read_trylock(&sbi->sb->s_umount)) { >> + cond_resched(); >> + goto retry_flush_quotas; >> + } >> + f2fs_do_quota_sync(sbi->sb, -1); >> + if (need_lock) >> up_read(&sbi->sb->s_umount); >> cond_resched(); >> goto retry_flush_quotas; > > Modified to: > /* don't grab s_umount lock during mount/umount/remount/freeze/quotactl */ > if (!need_lock) { > f2fs_do_quota_sync(sbi->sb, -1); > } else if (down_read_trylock(&sbi->sb->s_umount)) { > f2fs_do_quota_sync(sbi->sb, -1); > up_read(&sbi->sb->s_umount); > } > cond_resched(); > goto retry_flush_quotas; Will update it into v2 anyway, thanks. Thanks, > >> @@ -1867,7 +1871,8 @@ int f2fs_issue_checkpoint(struct f2fs_sb_info *sbi) >> struct cp_control cpc; >> >> cpc.reason = __get_cp_reason(sbi); >> - if (!test_opt(sbi, MERGE_CHECKPOINT) || cpc.reason != CP_SYNC) { >> + if (!test_opt(sbi, MERGE_CHECKPOINT) || cpc.reason != CP_SYNC || >> + sbi->umount_lock_holder == current) { >> int ret; >> >> f2fs_down_write(&sbi->gc_lock); >> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h >> index 62b7fed1514a..7174dea641e9 100644 >> --- a/fs/f2fs/f2fs.h >> +++ b/fs/f2fs/f2fs.h >> @@ -1670,6 +1670,7 @@ struct f2fs_sb_info { >> >> unsigned int nquota_files; /* # of quota sysfile */ >> struct f2fs_rwsem quota_sem; /* blocking cp for flags */ >> + struct task_struct *umount_lock_holder; /* s_umount lock holder */ >> >> /* # of pages, see count_type */ >> atomic_t nr_pages[NR_COUNT_TYPE]; >> @@ -3652,7 +3653,7 @@ int f2fs_inode_dirtied(struct inode *inode, bool sync); >> void f2fs_inode_synced(struct inode *inode); >> int f2fs_dquot_initialize(struct inode *inode); >> int f2fs_enable_quota_files(struct f2fs_sb_info *sbi, bool rdonly); >> -int f2fs_quota_sync(struct super_block *sb, int type); >> +int f2fs_do_quota_sync(struct super_block *sb, int type); >> loff_t max_file_blocks(struct inode *inode); >> void f2fs_quota_off_umount(struct super_block *sb); >> void f2fs_save_errors(struct f2fs_sb_info *sbi, unsigned char flag); >> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c >> index ef639a6d82e5..cb9d7b6fa3ad 100644 >> --- a/fs/f2fs/super.c >> +++ b/fs/f2fs/super.c >> @@ -1740,22 +1740,28 @@ int f2fs_sync_fs(struct super_block *sb, int sync) >> >> static int f2fs_freeze(struct super_block *sb) >> { >> + struct f2fs_sb_info *sbi = F2FS_SB(sb); >> + >> if (f2fs_readonly(sb)) >> return 0; >> >> /* IO error happened before */ >> - if (unlikely(f2fs_cp_error(F2FS_SB(sb)))) >> + if (unlikely(f2fs_cp_error(sbi))) >> return -EIO; >> >> /* must be clean, since sync_filesystem() was already called */ >> - if (is_sbi_flag_set(F2FS_SB(sb), SBI_IS_DIRTY)) >> + if (is_sbi_flag_set(sbi, SBI_IS_DIRTY)) >> return -EINVAL; >> >> + sbi->umount_lock_holder = current; >> + >> /* Let's flush checkpoints and stop the thread. */ >> - f2fs_flush_ckpt_thread(F2FS_SB(sb)); >> + f2fs_flush_ckpt_thread(sbi); >> + >> + sbi->umount_lock_holder = NULL; >> >> /* to avoid deadlock on f2fs_evict_inode->SB_FREEZE_FS */ >> - set_sbi_flag(F2FS_SB(sb), SBI_IS_FREEZING); >> + set_sbi_flag(sbi, SBI_IS_FREEZING); >> return 0; >> } >> >> @@ -2332,6 +2338,8 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data) >> org_mount_opt = sbi->mount_opt; >> old_sb_flags = sb->s_flags; >> >> + sbi->umount_lock_holder = current; >> + >> #ifdef CONFIG_QUOTA >> org_mount_opt.s_jquota_fmt = F2FS_OPTION(sbi).s_jquota_fmt; >> for (i = 0; i < MAXQUOTAS; i++) { >> @@ -2555,6 +2563,8 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data) >> >> limit_reserve_root(sbi); >> *flags = (*flags & ~SB_LAZYTIME) | (sb->s_flags & SB_LAZYTIME); >> + >> + sbi->umount_lock_holder = NULL; >> return 0; >> restore_checkpoint: >> if (need_enable_checkpoint) { >> @@ -2595,6 +2605,8 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data) >> #endif >> sbi->mount_opt = org_mount_opt; >> sb->s_flags = old_sb_flags; >> + >> + sbi->umount_lock_holder = NULL; >> return err; >> } >> >> @@ -2911,7 +2923,7 @@ static int f2fs_quota_sync_file(struct f2fs_sb_info *sbi, int type) >> return ret; >> } >> >> -int f2fs_quota_sync(struct super_block *sb, int type) >> +int f2fs_do_quota_sync(struct super_block *sb, int type) >> { >> struct f2fs_sb_info *sbi = F2FS_SB(sb); >> struct quota_info *dqopt = sb_dqopt(sb); >> @@ -2959,6 +2971,16 @@ int f2fs_quota_sync(struct super_block *sb, int type) >> return ret; >> } >> >> +static int f2fs_quota_sync(struct super_block *sb, int type) >> +{ >> + int ret; >> + >> + F2FS_SB(sb)->umount_lock_holder = current; >> + ret = f2fs_do_quota_sync(sb, type); >> + F2FS_SB(sb)->umount_lock_holder = NULL; >> + return ret; >> +} >> + >> static int f2fs_quota_on(struct super_block *sb, int type, int format_id, >> const struct path *path) >> { >> @@ -2974,30 +2996,33 @@ static int f2fs_quota_on(struct super_block *sb, int type, int format_id, >> if (path->dentry->d_sb != sb) >> return -EXDEV; >> >> - err = f2fs_quota_sync(sb, type); >> + F2FS_SB(sb)->umount_lock_holder = current; >> + >> + err = f2fs_do_quota_sync(sb, type); >> if (err) >> - return err; >> + goto out; >> >> inode = d_inode(path->dentry); >> >> err = filemap_fdatawrite(inode->i_mapping); >> if (err) >> - return err; >> + goto out; >> >> err = filemap_fdatawait(inode->i_mapping); >> if (err) >> - return err; >> + goto out; >> >> err = dquot_quota_on(sb, type, format_id, path); >> if (err) >> - return err; >> + goto out; >> >> inode_lock(inode); >> F2FS_I(inode)->i_flags |= F2FS_QUOTA_DEFAULT_FL; >> f2fs_set_inode_flags(inode); >> inode_unlock(inode); >> f2fs_mark_inode_dirty_sync(inode, false); >> - >> +out: >> + F2FS_SB(sb)->umount_lock_holder = NULL; >> return 0; >> } >> >> @@ -3009,7 +3034,7 @@ static int __f2fs_quota_off(struct super_block *sb, int type) >> if (!inode || !igrab(inode)) >> return dquot_quota_off(sb, type); >> >> - err = f2fs_quota_sync(sb, type); >> + err = f2fs_do_quota_sync(sb, type); >> if (err) >> goto out_put; >> >> @@ -3032,6 +3057,8 @@ static int f2fs_quota_off(struct super_block *sb, int type) >> struct f2fs_sb_info *sbi = F2FS_SB(sb); >> int err; >> >> + F2FS_SB(sb)->umount_lock_holder = current; >> + >> err = __f2fs_quota_off(sb, type); >> >> /* >> @@ -3041,6 +3068,9 @@ static int f2fs_quota_off(struct super_block *sb, int type) >> */ >> if (is_journalled_quota(sbi)) >> set_sbi_flag(sbi, SBI_QUOTA_NEED_REPAIR); >> + >> + F2FS_SB(sb)->umount_lock_holder = NULL; >> + >> return err; >> } >> >> @@ -4715,6 +4745,7 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent) >> if (err) >> goto free_compress_inode; >> >> + sbi->umount_lock_holder = current; >> #ifdef CONFIG_QUOTA >> /* Enable quota usage during mount */ >> if (f2fs_sb_has_quota_ino(sbi) && !f2fs_readonly(sb)) { >> @@ -4841,6 +4872,8 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent) >> f2fs_update_time(sbi, CP_TIME); >> f2fs_update_time(sbi, REQ_TIME); >> clear_sbi_flag(sbi, SBI_CP_DISABLED_QUICK); >> + >> + sbi->umount_lock_holder = NULL; >> return 0; >> >> sync_free_meta: >> @@ -4945,6 +4978,8 @@ static void kill_f2fs_super(struct super_block *sb) >> struct f2fs_sb_info *sbi = F2FS_SB(sb); >> >> if (sb->s_root) { >> + sbi->umount_lock_holder = current; >> + >> set_sbi_flag(sbi, SBI_IS_CLOSE); >> f2fs_stop_gc_thread(sbi); >> f2fs_stop_discard_thread(sbi); >> -- >> 2.48.1.502.g6dc24dfdaf-goog