From mboxrd@z Thu Jan  1 00:00:00 1970
From: "J. R. Okajima" <hooanon05@yahoo.co.jp>
Subject: Re: Important for fs devs: rcu-walk merged upstream
Date: Mon, 10 Jan 2011 23:38:47 +0900
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References: <AANLkTimBrR1LkVHOxZA=UUmKsnxfsFLr9z_AhXUHQ_7N@mail.gmail.com>
Cc: linux-fsdevel <linux-fsdevel@vger.kernel.org>,
	linux-kernel@vger.kernel.org
To: Nick Piggin <npiggin@gmail.com>
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Nick Piggin:
> This is a big and complex change by any measure, so
> please don't be afraid to ask for help or clarification. I'd
> also really like to be able to update documentation
> based on questions from fs maintainers (in and out of
> tree) who are trying to follow it and bring their code up to
> speed.

Question about what d_lock protects.
Can we skip d_lock when we access d_inode and d_name during its parent
i_mutex is held?
Should these BUG_ON be placed after d_lock?

void dentry_update_name_case(struct dentry *dentry, struct qstr *name)
{
	BUG_ON(!mutex_is_locked(&dentry->d_inode->i_mutex));
	BUG_ON(dentry->d_name.len != name->len); /* d_lookup gives this */

	spin_lock(&dentry->d_lock);
	:::


J. R. Okajima