From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Bottomley Subject: Re: NBD (vs. iSCSI vs. EATA vs...) (fwd) Date: Sat, 28 May 2005 15:12:00 -0400 Message-ID: <1117307520.5192.3.camel@mulgrave> References: Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Received: from stat16.steeleye.com ([209.192.50.48]:22205 "EHLO hancock.sc.steeleye.com") by vger.kernel.org with ESMTP id S261189AbVE1TMG (ORCPT ); Sat, 28 May 2005 15:12:06 -0400 In-Reply-To: Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Guennadi Liakhovetski Cc: SCSI Mailing List On Sat, 2005-05-28 at 10:32 +0200, Guennadi Liakhovetski wrote: > So, just pass ioctl()'s directly and convert the rest (filesystem) > block > requests separately - wouldn't it be easier and avoid any > modifications to > other drivers? Before you go any further, I suggest you think about what an ioctl is and why we're going through a process of trying to get rid of them in the kernel: They're structured streams of information, where the structure is architecture and 64/32 bit dependent (look at all the issues over compat ioctls). Inherently these things will be incredibly nasty to convert to an architecture neutral network protocol, and you'll have to provide a translator to and from every possible ioctl...they're inherently unsuitable things for building a protocol on top of. On the other hand, the current nbd protocol is block request based, which is why I suggested looking at that instead. James