From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg KH Subject: Re: [PATCH 3/5] add sg segment limitation info to device structure Date: Wed, 26 Sep 2007 09:05:58 -0700 Message-ID: <20070926160558.GA10819@suse.de> References: <20070925142157B.tomof@acm.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from cantor2.suse.de ([195.135.220.15]:36576 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752770AbXIZQND (ORCPT ); Wed, 26 Sep 2007 12:13:03 -0400 Content-Disposition: inline In-Reply-To: <20070925142157B.tomof@acm.org> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: FUJITA Tomonori Cc: James.Bottomley@SteelEye.com, jens.axboe@oracle.com, hch@infradead.org, jeff@garzik.org, hare@suse.de, linux-scsi@vger.kernel.org, fujita.tomonori@lab.ntt.co.jp On Wed, Sep 26, 2007 at 05:58:01PM +0900, FUJITA Tomonori wrote: > iommu code merges sg segments without considering lld's sg segment > restrictions. iommu code can't access to the limitations because they > are in request_queue. This patch adds max_segment_size to device > structure. seg_boundary_mask will be added too later. > > Signed-off-by: FUJITA Tomonori > --- > include/linux/device.h | 7 +++++++ > 1 files changed, 7 insertions(+), 0 deletions(-) > > diff --git a/include/linux/device.h b/include/linux/device.h > index 3a38d1f..8046b60 100644 > --- a/include/linux/device.h > +++ b/include/linux/device.h > @@ -443,6 +443,13 @@ struct device { > > struct dma_coherent_mem *dma_mem; /* internal for coherent mem > override */ > + > + /* > + * a low level driver may set these to teach IOMMU code about > + * sg limitations. > + */ > + unsigned int max_segment_size; Does this really need to be here? Can't it go into the bus specific device that needs this? thanks, greg k-h