From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ftp.linux.org.uk>
Subject: Re: [RFC][PATCH 11/20] elevate write count over calls to vfs_rename()
Date: Sun, 18 Jun 2006 19:23:59 +0100
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	herbert@13thfloor.at, Trond Myklebust <trond.myklebust@fys.uio.no>
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	Sun, 18 Jun 2006 14:24:01 -0400
To: Dave Hansen <haveblue@us.ibm.com>
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On Fri, Jun 16, 2006 at 04:12:21PM -0700, Dave Hansen wrote:
> +	err = mnt_want_write(ffhp->fh_export->ex_mnt);
> +	if (err)
> +		goto out_dput_new;
> +
> +	err = mnt_want_write(tfhp->fh_export->ex_mnt);
> +	if (err)
> +		goto out_mnt_drop_write_old;
> +
>  	err = vfs_rename(fdir, odentry, tdir, ndentry);
>  	if (!err && EX_ISSYNC(tfhp->fh_export)) {
>  		err = nfsd_sync_dir(tdentry);
>  		if (!err)
>  			err = nfsd_sync_dir(fdentry);
>  	}
> -
> +	mnt_drop_write(tfhp->fh_export->ex_mnt);
> + out_mnt_drop_write_old:
> +	mnt_drop_write(ffhp->fh_export->ex_mnt);

Ahem...
	a) nfsd_rename() should check that tfhp->fh_export->ex_mnt ==
ffhp->fh_export->ex_mnt (if not that tfhp->fh_export == ffhp->fh_export)
instead of comparing ->i_sb
	b) that patch should do mnt_want_write() only once.