Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262143AbTENHWc (ORCPT ); Wed, 14 May 2003 03:22:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262148AbTENHWc (ORCPT ); Wed, 14 May 2003 03:22:32 -0400 Received: from e34.co.us.ibm.com ([32.97.110.132]:2442 "EHLO e34.co.us.ibm.com") by vger.kernel.org with ESMTP id S262143AbTENHWb (ORCPT ); Wed, 14 May 2003 03:22:31 -0400 Date: Wed, 14 May 2003 00:37:00 -0700 From: Mike Anderson To: "Justin T. Gibbs" Cc: William Lee Irwin III , linux-kernel@vger.kernel.org, axel@pearbough.net, axboe@suse.de Subject: Re: drivers/scsi/aic7xxx/aic7xxx_osm.c: warning is error Message-ID: <20030514073700.GA3151@beaverton.ibm.com> Mail-Followup-To: "Justin T. Gibbs" , William Lee Irwin III , linux-kernel@vger.kernel.org, axel@pearbough.net, axboe@suse.de References: <20030514004009.GA20914@neon.pearbough.net> <20030514031826.GB29926@holomorphy.com> <493702704.1052892304@aslan.scsiguy.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <493702704.1052892304@aslan.scsiguy.com> X-Operating-System: Linux 2.0.32 on an i486 User-Agent: Mutt/1.5.3i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1312 Lines: 37 Justin T. Gibbs [gibbs@scsiguy.com] wrote: > Comments have indicated since the 2.4.X days that Linux will never allocate > segments that cross a 4GB boundary. If this is truely enforced, then this > code can just be removed. It was only added out of paranoia (hence the > printf) while adding high address support to the driver. Jens can give the more complete answer on enforcement, and also correct any mis-statements I made. Base on the queue values below the aic7xxx driver should see the following characteristics on IO. The IO should be for no more than 8k made up of no more than 128 sg entries with no segment crossing the seg_boundary_mask. Adaptec AIC7xxx driver version: 6.2.33 scsi_alloc_queue: queue for aic7xxx bounce_pfn: 0xfffff bounce_gfp: 0x10 (GFP_NOIO) queue_flags: 0x1 (QUEUE_FLAG_QUEUED) max_sectors: 0x2000 (8192) max_phys_segments: 0x80 (128) max_hw_segments: 0x80 (128) hardsect_size: 0x200 (512) max_segment_size: 0x10000 (65536) seg_boundary_mask: 0xffffffff dma_alignment: 0x1ff (511) -andmike -- Michael Anderson andmike@us.ibm.com - 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/