Commit 512f62ac authored by Joseph Qi's avatar Joseph Qi Committed by Linus Torvalds
Browse files

ocfs2: fix race between dio and recover orphan 



During direct io the inode will be added to orphan first and then
deleted from orphan.  There is a race window that the orphan entry will
be deleted twice and thus trigger the BUG when validating
OCFS2_DIO_ORPHANED_FL in ocfs2_del_inode_from_orphan.

ocfs2_direct_IO_write
    ...
    ocfs2_add_inode_to_orphan
    >>>>>>>> race window.
             1) another node may rm the file and then down, this node
             take care of orphan recovery and clear flag
             OCFS2_DIO_ORPHANED_FL.
             2) since rw lock is unlocked, it may race with another
             orphan recovery and append dio.
    ocfs2_del_inode_from_orphan

So take inode mutex lock when recovering orphans and make rw unlock at the
end of aio write in case of append dio.

Signed-off-by: default avatarJoseph Qi <joseph.qi@huawei.com>
Reported-by: default avatarYiwen Jiang <jiangyiwen@huawei.com>
Cc: Weiwei Wang <wangww631@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 81cf09ed

fs/ocfs2/aops.c

+6 −3
Original line number Diff line number Diff line
@@ -627,11 +627,14 @@ static void ocfs2_dio_end_io(struct kiocb *iocb, 
		mutex_unlock(&OCFS2_I(inode)->ip_unaligned_aio);

	}



	/* Let rw unlock to be done later to protect append direct io write */

	if (offset + bytes <= i_size_read(inode)) {

		ocfs2_iocb_clear_rw_locked(iocb);



		level = ocfs2_iocb_rw_locked_level(iocb);

		ocfs2_rw_unlock(inode, level);

	}

}



static int ocfs2_releasepage(struct page *page, gfp_t wait)

{

fs/ocfs2/file.c

+1 −1
Original line number Diff line number Diff line
@@ -2416,7 +2416,7 @@ relock: 
	}



no_sync:

	if (unaligned_dio) {

	if (unaligned_dio && ocfs2_iocb_is_unaligned_aio(iocb)) {

		ocfs2_iocb_clear_unaligned_aio(iocb);

		mutex_unlock(&OCFS2_I(inode)->ip_unaligned_aio);

	}

fs/ocfs2/inode.h

+0 −2
Original line number Diff line number Diff line
@@ -81,8 +81,6 @@ struct ocfs2_inode_info 
	tid_t i_sync_tid;

	tid_t i_datasync_tid;



	wait_queue_head_t append_dio_wq;



	struct dquot *i_dquot[MAXQUOTAS];

};

fs/ocfs2/journal.c

+4 −4
Original line number Diff line number Diff line
@@ -2170,6 +2170,7 @@ static int ocfs2_recover_orphans(struct ocfs2_super *osb, 
		iter = oi->ip_next_orphan;

		oi->ip_next_orphan = NULL;



		mutex_lock(&inode->i_mutex);

		ret = ocfs2_rw_lock(inode, 1);

		if (ret < 0) {

			mlog_errno(ret);
@@ -2206,17 +2207,16 @@ static int ocfs2_recover_orphans(struct ocfs2_super *osb, 
			ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, 0, 0);

			if (ret)

				mlog_errno(ret);



			wake_up(&OCFS2_I(inode)->append_dio_wq);

		} /* else if ORPHAN_NO_NEED_TRUNCATE, do nothing */

unlock_inode:

		ocfs2_inode_unlock(inode, 1);

		brelse(di_bh);

		di_bh = NULL;

unlock_rw:

		ocfs2_rw_unlock(inode, 1);

next:

		mutex_unlock(&inode->i_mutex);

		iput(inode);

		brelse(di_bh);

		di_bh = NULL;

		inode = iter;

	}

fs/ocfs2/namei.c

+13 −29
Original line number Diff line number Diff line
@@ -2601,27 +2601,6 @@ leave: 
	return status;

}



static int ocfs2_dio_orphan_recovered(struct inode *inode)

{

	int ret;

	struct buffer_head *di_bh = NULL;

	struct ocfs2_dinode *di = NULL;



	ret = ocfs2_inode_lock(inode, &di_bh, 1);

	if (ret < 0) {

		mlog_errno(ret);

		return 0;

	}



	di = (struct ocfs2_dinode *) di_bh->b_data;

	ret = !(di->i_flags & cpu_to_le32(OCFS2_DIO_ORPHANED_FL));

	ocfs2_inode_unlock(inode, 1);

	brelse(di_bh);



	return ret;

}



#define OCFS2_DIO_ORPHANED_FL_CHECK_INTERVAL 10000

int ocfs2_add_inode_to_orphan(struct ocfs2_super *osb,

	struct inode *inode)

{
@@ -2633,7 +2612,6 @@ int ocfs2_add_inode_to_orphan(struct ocfs2_super *osb, 
	handle_t *handle = NULL;

	struct ocfs2_dinode *di = NULL;



restart:

	status = ocfs2_inode_lock(inode, &di_bh, 1);

	if (status < 0) {

		mlog_errno(status);
@@ -2643,15 +2621,21 @@ restart: 
	di = (struct ocfs2_dinode *) di_bh->b_data;

	/*

	 * Another append dio crashed?

	 * If so, wait for recovery first.

	 * If so, manually recover it first.

	 */

	if (unlikely(di->i_flags & cpu_to_le32(OCFS2_DIO_ORPHANED_FL))) {

		ocfs2_inode_unlock(inode, 1);

		brelse(di_bh);

		wait_event_interruptible_timeout(OCFS2_I(inode)->append_dio_wq,

				ocfs2_dio_orphan_recovered(inode),

				msecs_to_jiffies(OCFS2_DIO_ORPHANED_FL_CHECK_INTERVAL));

		goto restart;

		status = ocfs2_truncate_file(inode, di_bh, i_size_read(inode));

		if (status < 0) {

			if (status != -ENOSPC)

				mlog_errno(status);

			goto bail_unlock_inode;

		}



		status = ocfs2_del_inode_from_orphan(osb, inode, di_bh, 0, 0);

		if (status < 0) {

			mlog_errno(status);

			goto bail_unlock_inode;

		}

	}



	status = ocfs2_prepare_orphan_dir(osb, &orphan_dir_inode,

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