From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ftp.linux.org.uk>
Subject: Re: [PATCH 01/14] NFS: Permit filesystem to
	override root dentry on mount [try #10]
Date: Tue, 30 May 2006 11:45:32 +0100
Message-ID: <20060530104532.GW27946@ftp.linux.org.uk>
References: <20060519154640.11791.2928.stgit@warthog.cambridge.redhat.com>
	<20060519154644.11791.72373.stgit@warthog.cambridge.redhat.com>
Reply-To: Linux filesystem caching discussion list <linux-cachefs@redhat.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Cc: akpm@osdl.org, aviro@redhat.com, linux-kernel@vger.kernel.org,
	nfsv4@linux-nfs.org, trond.myklebust@fys.uio.no, torvalds@osdl.org,
	linux-cachefs@redhat.com, linux-fsdevel@vger.kernel.org
Return-path: <linux-cachefs-bounces@redhat.com>
To: David Howells <dhowells@redhat.com>
Content-Disposition: inline
In-Reply-To: <20060519154644.11791.72373.stgit@warthog.cambridge.redhat.com>
List-Unsubscribe: <https://www.redhat.com/mailman/listinfo/linux-cachefs>,
	<mailto:linux-cachefs-request@redhat.com?subject=unsubscribe>
List-Archive: <https://www.redhat.com/archives/linux-cachefs>
List-Post: <mailto:linux-cachefs@redhat.com>
List-Help: <mailto:linux-cachefs-request@redhat.com?subject=help>
List-Subscribe: <https://www.redhat.com/mailman/listinfo/linux-cachefs>,
	<mailto:linux-cachefs-request@redhat.com?subject=subscribe>
Sender: linux-cachefs-bounces@redhat.com
Errors-To: linux-cachefs-bounces@redhat.com
List-Id: linux-fsdevel.vger.kernel.org

On Fri, May 19, 2006 at 04:46:45PM +0100, David Howells wrote:
>  informative error value to report).  Call it foo_fill_super().  Now declare
>  
> -struct super_block foo_get_sb(struct file_system_type *fs_type,
> -	int flags, const char *dev_name, void *data)
> +int foo_get_sb(struct file_system_type *fs_type,
> +	int flags, const char *dev_name, void *data, struct vfsmount *mnt)
>  {
> -	return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super);
> +	return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super,
> +			   mnt);
>  }

BTW, s/ext2_fill_super/foo_fill_super/, while we are at it...

> +	BUG_ON(!mnt->mnt_sb);
> +	BUG_ON(!mnt->mnt_sb->s_root);
> +	BUG_ON(!mnt->mnt_root);

FWIW, I'm not sure it's needed.  We do
> +	up_write(&mnt->mnt_sb->s_umount);

soon enough and it will catch all likely breakage without cluttering
the code with BUG_ON().  Other than that, no objections.