From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752117AbaABQ1X (ORCPT ); Thu, 2 Jan 2014 11:27:23 -0500 Received: from smtp.citrix.com ([66.165.176.89]:9117 "EHLO SMTP.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751849AbaABQ1W (ORCPT ); Thu, 2 Jan 2014 11:27:22 -0500 X-IronPort-AV: E=Sophos;i="4.95,591,1384300800"; d="scan'208";a="89275865" Message-ID: <52C59367.70707@citrix.com> Date: Thu, 2 Jan 2014 16:27:19 +0000 From: David Vrabel User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.16) Gecko/20121215 Iceowl/1.0b1 Icedove/3.0.11 MIME-Version: 1.0 To: Konrad Rzeszutek Wilk CC: , , , , Subject: Re: [PATCH v12 14/18] xen/grant: Implement an grant frame array struct. References: <1388550945-25499-1-git-send-email-konrad.wilk@oracle.com> <1388550945-25499-15-git-send-email-konrad.wilk@oracle.com> In-Reply-To: <1388550945-25499-15-git-send-email-konrad.wilk@oracle.com> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.80.2.76] X-DLP: MIA2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/01/14 04:35, Konrad Rzeszutek Wilk wrote: > The 'xen_hvm_resume_frames' used to be an 'unsigned long' > and contain the virtual address of the grants. That was OK > for most architectures (PVHVM, ARM) were the grants are contingous > in memory. That however is not the case for PVH - in which case > we will have to do a lookup for each virtual address for the PFN. > > Instead of doing that, lets make it a structure which will contain > the array of PFNs, the virtual address and the count of said PFNs. > > Also provide a generic functions: gnttab_setup_auto_xlat_frames and > gnttab_free_auto_xlat_frames to populate said structure with > appropiate values for PVHVM and ARM. > > To round it off, change the name from 'xen_hvm_resume_frames' to > a more descriptive one - 'xen_auto_xlat_grant_frames'. > > For PVH, in patch "xen/pvh: Piggyback on PVHVM for grant driver" > we will populate the 'xen_auto_xlat_grant_frames' by ourselves. [...] > --- a/drivers/xen/grant-table.c > +++ b/drivers/xen/grant-table.c [...] > @@ -838,6 +838,40 @@ unsigned int gnttab_max_grant_frames(void) > } > EXPORT_SYMBOL_GPL(gnttab_max_grant_frames); > > +int gnttab_setup_auto_xlat_frames(unsigned long addr) > +{ > + xen_pfn_t *pfn; > + unsigned int max_nr_gframes = __max_nr_grant_frames(); > + int i; > + > + if (xen_auto_xlat_grant_frames.count) > + return -EINVAL; > + > + pfn = kcalloc(max_nr_gframes, sizeof(pfn[0]), GFP_KERNEL); > + if (!pfn) > + return -ENOMEM; > + for (i = 0; i < max_nr_gframes; i++) > + pfn[i] = PFN_DOWN(addr + (i * PAGE_SIZE)); PFN_DOWN(addr) + i looks better to me. > + > + xen_auto_xlat_grant_frames.vaddr = addr; Huh? addr is a physical address but you're assigning it to a field called vaddr? I think you mean to set this field to the result of the xen_remap() call, yes? > --- a/include/xen/grant_table.h > +++ b/include/xen/grant_table.h > @@ -178,8 +178,15 @@ int arch_gnttab_map_status(uint64_t *frames, unsigned long nr_gframes, > grant_status_t **__shared); > void arch_gnttab_unmap(void *shared, unsigned long nr_gframes); > > -extern unsigned long xen_hvm_resume_frames; > +struct grant_frames { > + xen_pfn_t *pfn; > + int count; unsigned int. > + unsigned long vaddr; void * if this is a virtual address. David