Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756523AbYGYNgS (ORCPT ); Fri, 25 Jul 2008 09:36:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753598AbYGYNgI (ORCPT ); Fri, 25 Jul 2008 09:36:08 -0400 Received: from sh.osrg.net ([192.16.179.4]:46014 "EHLO sh.osrg.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753540AbYGYNgF (ORCPT ); Fri, 25 Jul 2008 09:36:05 -0400 Date: Fri, 25 Jul 2008 22:34:57 +0900 To: joerg.roedel@amd.com Cc: fujita.tomonori@lab.ntt.co.jp, mingo@redhat.com, tglx@linutronix.de, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, bhavna.sarathy@amd.com, robert.richter@amd.com Subject: Re: [PATCH] add iommu_num_pages helper function From: FUJITA Tomonori In-Reply-To: <20080725132121.GZ7493@amd.com> References: <1216990680-1227-2-git-send-email-joerg.roedel@amd.com> <20080725221553Q.fujita.tomonori@lab.ntt.co.jp> <20080725132121.GZ7493@amd.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-Id: <20080725223533A.fujita.tomonori@lab.ntt.co.jp> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2460 Lines: 56 On Fri, 25 Jul 2008 15:21:21 +0200 Joerg Roedel wrote: > On Fri, Jul 25, 2008 at 10:15:06PM +0900, FUJITA Tomonori wrote: > > On Fri, 25 Jul 2008 14:57:58 +0200 > > Joerg Roedel wrote: > > > > > Calculating the number of pages from given address and length numbers is a task > > > required in multiple IOMMU implementations. So implement this as a generic > > > function into the IOMMU helper code. > > > > > > Cc: FUJITA Tomonori > > > Signed-off-by: Joerg Roedel > > > --- > > > include/linux/iommu-helper.h | 1 + > > > lib/iommu-helper.c | 8 ++++++++ > > > 2 files changed, 9 insertions(+), 0 deletions(-) > > > > Thanks. I planed to work on this after rc1. You beat me. :) > > > > > > > diff --git a/include/linux/iommu-helper.h b/include/linux/iommu-helper.h > > > index c975caf..f8598f5 100644 > > > --- a/include/linux/iommu-helper.h > > > +++ b/include/linux/iommu-helper.h > > > @@ -8,3 +8,4 @@ extern unsigned long iommu_area_alloc(unsigned long *map, unsigned long size, > > > unsigned long align_mask); > > > extern void iommu_area_free(unsigned long *map, unsigned long start, > > > unsigned int nr); > > > +extern unsigned long iommu_num_pages(unsigned long addr, unsigned long len); > > > diff --git a/lib/iommu-helper.c b/lib/iommu-helper.c > > > index a3b8d4c..889ddce 100644 > > > --- a/lib/iommu-helper.c > > > +++ b/lib/iommu-helper.c > > > @@ -80,3 +80,11 @@ void iommu_area_free(unsigned long *map, unsigned long start, unsigned int nr) > > > } > > > } > > > EXPORT_SYMBOL(iommu_area_free); > > > + > > > +unsigned long iommu_num_pages(unsigned long addr, unsigned long len) > > > +{ > > > + unsigned long size = roundup((addr & ~PAGE_MASK) + len, PAGE_SIZE); > > > + > > > + return size >> PAGE_SHIFT; > > > +} > > > +EXPORT_SYMBOL(iommu_num_pages); > > > > This doesn't work since PAGE_SIZE != IOMMU_PAGE_SIZE on the majority > > of architectures. > > A quick grep in include/ tells me that only powerpc is declaring > IOMMU_PAGE_SIZE by now. Ah, I just meant the I/O size of IOMMUs. This macro doesn't work for IA64, POWER, and SPARC. -- 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/