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charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net It seems you need to remove dummy f2fs_quota_sync() in fs/f2fs/super.c to fix the build error. 3204 int f2fs_quota_sync(struct super_block *sb, int type) 3205 { 3206 return 0; 3207 } On 02/07, 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 not 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 > --- > v2: > - fix to return correct error number in f2fs_quota_on() > - clean up codes in block_operations() > - fix commit message > fs/f2fs/checkpoint.c | 15 ++++++----- > fs/f2fs/f2fs.h | 3 ++- > fs/f2fs/super.c | 63 ++++++++++++++++++++++++++++++++++---------- > 3 files changed, 60 insertions(+), 21 deletions(-) > > diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c > index efda9a022981..bd890738b94d 100644 > --- a/fs/f2fs/checkpoint.c > +++ b/fs/f2fs/checkpoint.c > @@ -1237,7 +1237,7 @@ 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; > > if (++cnt > DEFAULT_RETRY_QUOTA_FLUSH_COUNT) { > set_sbi_flag(sbi, SBI_QUOTA_SKIP_FLUSH); > @@ -1246,11 +1246,13 @@ 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) { > + 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; > } > @@ -1867,7 +1869,8 @@ 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 bd0d8138b71d..205bdcbd01e6 100644 > --- a/fs/f2fs/f2fs.h > +++ b/fs/f2fs/f2fs.h > @@ -1668,6 +1668,7 @@ 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]; > @@ -3633,7 +3634,7 @@ 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 24ded06c8980..944b09fd3aca 100644 > --- a/fs/f2fs/super.c > +++ b/fs/f2fs/super.c > @@ -1738,22 +1738,28 @@ 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; > } > > @@ -2330,6 +2336,8 @@ 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++) { > @@ -2553,6 +2561,8 @@ 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) { > @@ -2593,6 +2603,8 @@ 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; > } > > @@ -2909,7 +2921,7 @@ 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); > @@ -2957,11 +2969,21 @@ 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) > { > struct inode *inode; > - int err; > + int err = 0; > > /* if quota sysfile exists, deny enabling quota with specific file */ > if (f2fs_sb_has_quota_ino(F2FS_SB(sb))) { > @@ -2972,31 +2994,34 @@ 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); > - > - return 0; > +out: > + F2FS_SB(sb)->umount_lock_holder = NULL; > + return err; > } > > static int __f2fs_quota_off(struct super_block *sb, int type) > @@ -3007,7 +3032,7 @@ 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; > > @@ -3030,6 +3055,8 @@ 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); > > /* > @@ -3039,6 +3066,9 @@ 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; > } > > @@ -4704,6 +4734,7 @@ 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)) { > @@ -4830,6 +4861,8 @@ 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: > @@ -4932,6 +4965,8 @@ 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 EE58718E750 for ; Fri, 7 Feb 2025 16:24:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738945496; cv=none; b=rWy8e+iuAALaYbsRKcjAzo6dfURW22GQgQWb3s77pOz4MVvmPJ67qfnvCLKyRI9v3csZSVqGkzeqKb9OGlFv0WG2YcpJe2EbUbOUtTrCZcHwwqEqQdHfli2TWZvrAOb3ue3u0l+jE2lQpiXVu82orFItMcy4w5+DD2Ji3tQCM2E= ARC-Message-Signature:i=1; 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b=EQPwjdLCGhdPrR2NTFmgg3GDZXdXy0ATRFWl5vuWLmp//2sutF9Pj+no872qGELug 3WIJUn63oZU1OPvofh8baRvltWiHTVywOJuYxwHUuRQ5Czww2Fl4K9spwISPqyVfYg gT+r5SslKGXR93xxgFu55P21dAoyyLAtZesig0mirFRBdNY8XhWzMCY6+S24fbvr7D n7GS0CrXIGqNfFQ5ZFer64q4U9sG1Ry7WkrdRtZMGFMwIMCdGhSu9ZpDfJjIF8kobT 1apFl8qQEGkbxBOsSvtUzT7QmuusMTwDSqMAgcPu4gDMq5jO3GDfTRmQhcmQe/lvga R1upa4U2kuDTg== Date: Fri, 7 Feb 2025 16:24:53 +0000 From: Jaegeuk Kim To: Chao Yu Cc: linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] f2fs: quota: fix to avoid warning in dquot_writeback_dquots() Message-ID: References: <20250207020441.3415568-1-chao@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250207020441.3415568-1-chao@kernel.org> It seems you need to remove dummy f2fs_quota_sync() in fs/f2fs/super.c to fix the build error. 3204 int f2fs_quota_sync(struct super_block *sb, int type) 3205 { 3206 return 0; 3207 } On 02/07, 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 not 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 > --- > v2: > - fix to return correct error number in f2fs_quota_on() > - clean up codes in block_operations() > - fix commit message > fs/f2fs/checkpoint.c | 15 ++++++----- > fs/f2fs/f2fs.h | 3 ++- > fs/f2fs/super.c | 63 ++++++++++++++++++++++++++++++++++---------- > 3 files changed, 60 insertions(+), 21 deletions(-) > > diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c > index efda9a022981..bd890738b94d 100644 > --- a/fs/f2fs/checkpoint.c > +++ b/fs/f2fs/checkpoint.c > @@ -1237,7 +1237,7 @@ 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; > > if (++cnt > DEFAULT_RETRY_QUOTA_FLUSH_COUNT) { > set_sbi_flag(sbi, SBI_QUOTA_SKIP_FLUSH); > @@ -1246,11 +1246,13 @@ 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) { > + 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; > } > @@ -1867,7 +1869,8 @@ 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 bd0d8138b71d..205bdcbd01e6 100644 > --- a/fs/f2fs/f2fs.h > +++ b/fs/f2fs/f2fs.h > @@ -1668,6 +1668,7 @@ 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]; > @@ -3633,7 +3634,7 @@ 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 24ded06c8980..944b09fd3aca 100644 > --- a/fs/f2fs/super.c > +++ b/fs/f2fs/super.c > @@ -1738,22 +1738,28 @@ 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; > } > > @@ -2330,6 +2336,8 @@ 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++) { > @@ -2553,6 +2561,8 @@ 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) { > @@ -2593,6 +2603,8 @@ 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; > } > > @@ -2909,7 +2921,7 @@ 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); > @@ -2957,11 +2969,21 @@ 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) > { > struct inode *inode; > - int err; > + int err = 0; > > /* if quota sysfile exists, deny enabling quota with specific file */ > if (f2fs_sb_has_quota_ino(F2FS_SB(sb))) { > @@ -2972,31 +2994,34 @@ 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); > - > - return 0; > +out: > + F2FS_SB(sb)->umount_lock_holder = NULL; > + return err; > } > > static int __f2fs_quota_off(struct super_block *sb, int type) > @@ -3007,7 +3032,7 @@ 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; > > @@ -3030,6 +3055,8 @@ 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); > > /* > @@ -3039,6 +3066,9 @@ 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; > } > > @@ -4704,6 +4734,7 @@ 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)) { > @@ -4830,6 +4861,8 @@ 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: > @@ -4932,6 +4965,8 @@ 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