Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sun, 1 Apr 2001 15:03:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sun, 1 Apr 2001 15:03:31 -0400 Received: from mailout05.sul.t-online.com ([194.25.134.82]:28164 "EHLO mailout05.sul.t-online.com") by vger.kernel.org with ESMTP id ; Sun, 1 Apr 2001 15:03:29 -0400 Date: 01 Apr 2001 13:48:00 +0200 From: kaih@khms.westfalen.de (Kai Henningsen) To: linux-kernel@vger.kernel.org Message-ID: <7z0azVOXw-B@khms.westfalen.de> In-Reply-To: Subject: Re: [RFC] sane access to per-fs metadata (was Re: [PATCH] Documentatio X-Mailer: CrossPoint v3.12d.kh5 R/C435 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Organization: Organisation? Me?! Are you kidding? In-Reply-To: X-No-Junk-Mail: I do not want to get *any* junk mail. Comment: Unsolicited commercial mail will incur an US$100 handling fee per received mail. X-Fix-Your-Modem: +++ATS2=255&WO1 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org chip@valinux.com (Chip Salzenberg) wrote on 01.04.01 in : > Why not have a kernel thread and use standard RPC techniques like > sockets? Then you'd not have to invent anything unimportant like > Yet Another IPC Technique. You can, of course, transfer the exact same RPC messages over a file descriptor on your metadata fs. It doesn't *have* to be ASCII, especially not for purely internal-use interfaces. And for ioctl() fans, you could transfer the exact same data via read()/ write() again. That's not significantly harder. Especially if you write a wrapper around the calls. If you want to be perverse, you can probably even transmit user space pointers. But I suspect there are really only two generally useful interfaces: 1. A text based interface for generally-useful stuff you might want to manipulate from the shell, or random user programs. (From the shell _is_ random user programs.) 2. A RPC based interface for tightly-coupled fs utilities. (I don't know off the top of my head what the kernel already has - ISTR networking has _something_.) Don't forget a version marker of some kind. Sooner or later, you'll be glad you have it. MfG Kai - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/