From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: [PATCH v2 4/8] xen: Use the correctly the Xen memory terminologies Date: Wed, 5 Aug 2015 11:51:01 +0100 Message-ID: <55C1EA95.5060504@citrix.com> References: <1438711972-18752-1-git-send-email-julien.grall@citrix.com> <1438711972-18752-5-git-send-email-julien.grall@citrix.com> <55C147DD.7000600@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Return-path: Received: from smtp.citrix.com ([66.165.176.89]:61894 "EHLO SMTP.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751677AbbHEKv5 (ORCPT ); Wed, 5 Aug 2015 06:51:57 -0400 In-Reply-To: <55C147DD.7000600@oracle.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Boris Ostrovsky , xen-devel@lists.xenproject.org Cc: linux-fbdev@vger.kernel.org, "H. Peter Anvin" , Jiri Slaby , stefano.stabellini@eu.citrix.com, Russell King , linux-scsi@vger.kernel.org, x86@kernel.org, Tomi Valkeinen , linux-input@vger.kernel.org, Jean-Christophe Plagniol-Villard , ian.campbell@citrix.com, Konrad Rzeszutek Wilk , "James E.J. Bottomley" , Thomas Gleixner , Ingo Molnar , linux-arm-kernel@lists.infradead.org, Juergen Gross , Wei Liu , Greg Kroah-Hartman , Dmitry Torokhov , linux-kernel@vger.kernel.org, David Vrabel , netdev@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, =?win Hi Boris, On 05/08/15 00:16, Boris Ostrovsky wrote: > On 08/04/2015 02:12 PM, Julien Grall wrote: >> /* >> * We detect special mappings in one of two ways: >> @@ -217,9 +232,13 @@ static inline unsigned long >> bfn_to_local_pfn(unsigned long mfn) >> /* VIRT <-> MACHINE conversion */ >> #define virt_to_machine(v) (phys_to_machine(XPADDR(__pa(v)))) >> -#define virt_to_pfn(v) (PFN_DOWN(__pa(v))) >> #define virt_to_mfn(v) (pfn_to_mfn(virt_to_pfn(v))) >> #define mfn_to_virt(m) (__va(mfn_to_pfn(m) << PAGE_SHIFT)) >> +#define virt_to_pfn(v) (PFN_DOWN(__pa(v))) > > This looks like unnecessary change. Right, I made the mistake when I re-introduced virt_to_mfn in this version. It was dropped in the previous one. >> diff --git a/drivers/video/fbdev/xen-fbfront.c >> b/drivers/video/fbdev/xen-fbfront.c >> index 09dc447..25e3cce 100644 >> --- a/drivers/video/fbdev/xen-fbfront.c >> +++ b/drivers/video/fbdev/xen-fbfront.c >> @@ -539,7 +539,7 @@ static int xenfb_remove(struct xenbus_device *dev) >> static unsigned long vmalloc_to_mfn(void *address) >> { >> - return pfn_to_mfn(vmalloc_to_pfn(address)); >> + return pfn_to_gfn(vmalloc_to_pfn(address)); >> } > > Are you sure? This will return vmalloc_to_pfn(address)). I guess you mean vmalloc_to_mfn will return vmalloc_to_pfn? If so, it will be only the case on auto-translated case (because pfn == gfn). In the case of PV, the mfn will be returned. Although, this function is misnamed. It's fixed in a follow-up patch (see #6) because it's required more renaming than this function. I didn't want to add such changes within this patch. Regards, -- Julien Grall