From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dmitry Monakhov <dmonakhov@openvz.org>
Subject: quota locking question
Date: Mon, 14 Dec 2009 17:30:49 +0300
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To: Jan Kara <jack@suse.cz>
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According to dquot.c locking rules: dq_data_lock guards consistency
of dquot->dq_dqb with inode->i_blocks, i_bytes.

It is no clear to me what is the reason. Why do we need it ?
What use-case causes this requirement?