quota: Fix double lock in add_dquot_ref() with CONFIG_QUOTA_DEBUG

When CONFIG_QUOTA_DEBUG is enabled we call inode_get_rsv_space() from
add_dquot_ref() while holding i_lock. But inode_get_rsv_space() is trying
to get i_lock as well resulting in double lock.

Fix the problem by moving inode_get_rsv_space() call out of i_lock.

Reported-and-analyzed-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
This commit is contained in:
Jan Kara 2012-04-24 17:08:41 +02:00
parent fd2cbd4dfa
commit d7e9711760

View File

@ -907,14 +907,14 @@ static void add_dquot_ref(struct super_block *sb, int type)
spin_unlock(&inode->i_lock);
continue;
}
#ifdef CONFIG_QUOTA_DEBUG
if (unlikely(inode_get_rsv_space(inode) > 0))
reserved = 1;
#endif
__iget(inode);
spin_unlock(&inode->i_lock);
spin_unlock(&inode_sb_list_lock);
#ifdef CONFIG_QUOTA_DEBUG
if (unlikely(inode_get_rsv_space(inode) > 0))
reserved = 1;
#endif
iput(old_inode);
__dquot_initialize(inode, type);