Re: Important for fs devs: rcu-walk merged upstream

["J. R. Okajima" <hooanon05@yahoo.co.jp>]

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