Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754202AbYJCPl5 (ORCPT ); Fri, 3 Oct 2008 11:41:57 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752789AbYJCPlr (ORCPT ); Fri, 3 Oct 2008 11:41:47 -0400 Received: from g1t0026.austin.hp.com ([15.216.28.33]:6393 "EHLO g1t0026.austin.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752579AbYJCPlq (ORCPT ); Fri, 3 Oct 2008 11:41:46 -0400 From: Bjorn Helgaas To: "Yu, Fenghua" Subject: Re: [PATCH 2/2]Add Variable Page Size and IA64 Support in Intel IOMMU: IA64 Specific Part Date: Fri, 3 Oct 2008 09:41:42 -0600 User-Agent: KMail/1.9.9 Cc: "Luck, Tony" , Jesse Barnes , David Woodhouse , Ingo Molnar , Avi Kivity , Stephen Rothwell , Andrew Morton , LKML , "linux-ia64@vger.kernel.org" References: <20081001165750.GA21272@linux-os.sc.intel.com> <200810020951.08408.bjorn.helgaas@hp.com> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200810030941.42800.bjorn.helgaas@hp.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1153 Lines: 25 On Thursday 02 October 2008 11:46:04 am Yu, Fenghua wrote: > >> --- a/arch/ia64/include/asm/cacheflush.h > >> +++ b/arch/ia64/include/asm/cacheflush.h > >> @@ -34,6 +34,8 @@ do { \ > >> #define flush_dcache_mmap_unlock(mapping) do { } while (0) > >> > >> extern void flush_icache_range (unsigned long start, unsigned long end); > >> +extern void clflush_cache_range(void *addr, int size); > > > >This patch adds clflush_cache_range(), but it's not used anywhere. > Clflush_cache_range() is used in __iommu_flush_cache() in include/linux/intel-iommu.h. Oh, OK. I didn't look hard enough to find __iommu_flush_cache() (currently in drivers/pci/intel-iommu.c). Architecturally, I'm surprised that ia64 would need to actually do a cache flush. I would think the VT-d hardware would do coherent accesses which would make the cache flush unnecessary. Bjorn -- 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/