From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751952Ab2INNTK (ORCPT ); Fri, 14 Sep 2012 09:19:10 -0400 Received: from acsinet15.oracle.com ([141.146.126.227]:31807 "EHLO acsinet15.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750841Ab2INNTI (ORCPT ); Fri, 14 Sep 2012 09:19:08 -0400 Date: Fri, 14 Sep 2012 09:08:07 -0400 From: Konrad Rzeszutek Wilk To: Stefano Stabellini Cc: arnd@arndb.de, linux@arm.linux.org.uk, catalin.marinas@arm.com, linaro-dev@lists.linaro.org, linux-arm-kernel@lists.infradead.org, tim@xen.org, Ian.Campbell@citrix.com, xen-devel@lists.xensource.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 07/24] xen/arm: Xen detection and shared_info page mapping Message-ID: <20120914130807.GK25249@phenom.dumpdata.com> References: <1347621207-11294-7-git-send-email-stefano.stabellini@eu.citrix.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1347621207-11294-7-git-send-email-stefano.stabellini@eu.citrix.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Source-IP: acsinet22.oracle.com [141.146.126.238] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 14, 2012 at 12:13:09PM +0100, Stefano Stabellini wrote: > Check for a node in the device tree compatible with "xen,xen", if it is > present set xen_domain_type to XEN_HVM_DOMAIN and continue > initialization. > > Map the real shared info page using XENMEM_add_to_physmap with > XENMAPSPACE_shared_info. > > Changes in v4: > > - simpler parsing of Xen version in the compatible DT node. > > Changes in v3: > > - use the "xen,xen" notation rather than "arm,xen"; > - add an additional check on the presence of the Xen version. > > Changes in v2: > > - replace pr_info with pr_debug. > > Signed-off-by: Stefano Stabellini > --- > arch/arm/xen/enlighten.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++ > 1 files changed, 61 insertions(+), 0 deletions(-) > > diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c > index c535540..6a0217d 100644 > --- a/arch/arm/xen/enlighten.c > +++ b/arch/arm/xen/enlighten.c > @@ -5,6 +5,9 @@ > #include > #include > #include > +#include > +#include > +#include > > struct start_info _xen_start_info; > struct start_info *xen_start_info = &_xen_start_info; > @@ -33,3 +36,61 @@ int xen_remap_domain_mfn_range(struct vm_area_struct *vma, > return -ENOSYS; > } > EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range); > + > +/* > + * see Documentation/devicetree/bindings/arm/xen.txt for the > + * documentation of the Xen Device Tree format. > + */ > +static int __init xen_guest_init(void) > +{ > + struct xen_add_to_physmap xatp; > + static struct shared_info *shared_info_page = 0; > + struct device_node *node; > + int len; > + const char *s = NULL; > + const char *version = NULL; > + const char *xen_prefix = "xen,xen-"; > + > + node = of_find_compatible_node(NULL, NULL, "xen,xen"); > + if (!node) { > + pr_debug("No Xen support\n"); > + return 0; > + } > + s = of_get_property(node, "compatible", &len); > + if (strlen(xen_prefix) + 3 < len && > + !strncmp(xen_prefix, s, strlen(xen_prefix))) If we have version '4.3.1' won't this trip us over? Or if we only have 'major' and 'minor', then won't '4.11' trip us over too? > + version = s + strlen(xen_prefix); > + if (version == NULL) { > + pr_debug("Xen version not found\n"); > + return 0; > + } > + xen_domain_type = XEN_HVM_DOMAIN; > + > + if (!shared_info_page) > + shared_info_page = (struct shared_info *) > + get_zeroed_page(GFP_KERNEL); > + if (!shared_info_page) { > + pr_err("not enough memory\n"); > + return -ENOMEM; > + } > + xatp.domid = DOMID_SELF; > + xatp.idx = 0; > + xatp.space = XENMAPSPACE_shared_info; > + xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT; > + if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp)) > + BUG(); > + > + HYPERVISOR_shared_info = (struct shared_info *)shared_info_page; > + > + /* xen_vcpu is a pointer to the vcpu_info struct in the shared_info > + * page, we use it in the event channel upcall and in some pvclock > + * related functions. We don't need the vcpu_info placement > + * optimizations because we don't use any pv_mmu or pv_irq op on > + * HVM. > + * The shared info contains exactly 1 CPU (the boot CPU). The guest > + * is required to use VCPUOP_register_vcpu_info to place vcpu info > + * for secondary CPUs as they are brought up. */ > + per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0]; > + return 0; > +} > +core_initcall(xen_guest_init); > -- > 1.7.2.5