From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: [patch 1/3] ps3: Disk Storage Driver Date: Thu, 19 Jul 2007 07:33:02 +0200 Message-ID: <20070719053302.GO11657@kernel.dk> References: <20070716161539.075822000@pademelon.sonytel.be> <20070716162206.392129000@pademelon.sonytel.be> <20070718163637.3f0e0164.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from brick.kernel.dk ([80.160.20.94]:9297 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752411AbXGSFdX (ORCPT ); Thu, 19 Jul 2007 01:33:23 -0400 Content-Disposition: inline In-Reply-To: <20070718163637.3f0e0164.akpm@linux-foundation.org> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Andrew Morton Cc: Geert Uytterhoeven , Andy Whitcroft , Paul Mackerras , "James E.J. Bottomley" , Alessandro Rubini , linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org, Geoff Levand On Wed, Jul 18 2007, Andrew Morton wrote: > On Mon, 16 Jul 2007 18:15:40 +0200 > Geert Uytterhoeven wrote: > > > From: Geert Uytterhoeven > > > > Add a Disk Storage Driver for the PS3: > > Your patchset significantly hits powerpc, scsi and block. So who gets to > merge this? Jens? James? Paul? > > Me, I guess ;) I think Paul was going to take it, or at least Geert hinted as such. > > +#define PS3DISK_MAX_DISKS 16 > > +#define PS3DISK_MINORS 16 > > + > > +#define KERNEL_SECTOR_SIZE 512 > > Sigh. We have at least ten separate definitions of SECTOR_SIZE< none of > them in the right place. Cleanup opportunity for someone. Indeed, it's universally 512 or << 9, just use that... > > +#ifdef DEBUG > > + unsigned int n = 0; > > + struct bio *bio; > > + rq_for_each_bio(bio, req) > > + n++; > > I'm surprised that the block core doesn't have a helper to count the number > of bios in a request. What would be the point of such a helper? I've never seen a need for it. Geert uses it as debug code here, but the fact is that the number of bios in a request is a pretty pointless number. It doesn't tell you anything. There's no 1:1 mapping between bios and segments (or anything else for that matter), so the exercise is purely pointless. -- Jens Axboe From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from kernel.dk (brick.kernel.dk [80.160.20.94]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "A common name", Issuer "A common name" (not verified)) by ozlabs.org (Postfix) with ESMTP id 433C7DDEBC for ; Thu, 19 Jul 2007 15:33:27 +1000 (EST) Date: Thu, 19 Jul 2007 07:33:02 +0200 From: Jens Axboe To: Andrew Morton Subject: Re: [patch 1/3] ps3: Disk Storage Driver Message-ID: <20070719053302.GO11657@kernel.dk> References: <20070716161539.075822000@pademelon.sonytel.be> <20070716162206.392129000@pademelon.sonytel.be> <20070718163637.3f0e0164.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20070718163637.3f0e0164.akpm@linux-foundation.org> Cc: "James E.J. Bottomley" , linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, Alessandro Rubini , linuxppc-dev@ozlabs.org, Paul Mackerras , Geert Uytterhoeven List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, Jul 18 2007, Andrew Morton wrote: > On Mon, 16 Jul 2007 18:15:40 +0200 > Geert Uytterhoeven wrote: > > > From: Geert Uytterhoeven > > > > Add a Disk Storage Driver for the PS3: > > Your patchset significantly hits powerpc, scsi and block. So who gets to > merge this? Jens? James? Paul? > > Me, I guess ;) I think Paul was going to take it, or at least Geert hinted as such. > > +#define PS3DISK_MAX_DISKS 16 > > +#define PS3DISK_MINORS 16 > > + > > +#define KERNEL_SECTOR_SIZE 512 > > Sigh. We have at least ten separate definitions of SECTOR_SIZE< none of > them in the right place. Cleanup opportunity for someone. Indeed, it's universally 512 or << 9, just use that... > > +#ifdef DEBUG > > + unsigned int n = 0; > > + struct bio *bio; > > + rq_for_each_bio(bio, req) > > + n++; > > I'm surprised that the block core doesn't have a helper to count the number > of bios in a request. What would be the point of such a helper? I've never seen a need for it. Geert uses it as debug code here, but the fact is that the number of bios in a request is a pretty pointless number. It doesn't tell you anything. There's no 1:1 mapping between bios and segments (or anything else for that matter), so the exercise is purely pointless. -- Jens Axboe