From: Avi Kivity Subject: Re: [PATCH v2 1/5] x86: Add helper variables and functions to hold VMCSINFO Date: Thu, 14 Jun 2012 16:28:42 +0300 Message-ID: <4FD9E70A.9090507@redhat.com> References: <4FB35C48.30708@cn.fujitsu.com> <4FB35CD4.3080801@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: dzickus-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, luto-3s7WtUTddSA@public.gmane.org, kvm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Joerg Roedel , mtosatti-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, kexec-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, paul.gortmaker-CWA4WttNNZF54TAoqtyWWQ@public.gmane.org, ludwig.nussel-l3A5Bk7waGM@public.gmane.org, ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org, Greg KH To: zhangyanfei Return-path: In-Reply-To: <4FB35CD4.3080801-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kexec-bounces-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org Errors-To: kexec-bounces+glkk-kexec=m.gmane.org-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: kvm.vger.kernel.org On 05/16/2012 10:52 AM, zhangyanfei wrote: > This patch provides a set of variables to hold the VMCSINFO and also > some helper functions to help fill the VMCSINFO. Need to document the format. > +void vmcsinfo_append_id(u32 id) > +{ > + size_t r; > + > + r = sizeof(id); > + if (r + vmcsinfo_size > vmcsinfo_max_size) > + return; > + > + memcpy(&vmcsinfo_data[vmcsinfo_size], &id, r); > + vmcsinfo_size += r; > +} > +EXPORT_SYMBOL_GPL(vmcsinfo_append_id); > + > +void vmcsinfo_append_field(u32 field, u64 offset) Why u64? It's guaranteed to fit within a page. > +{ > + size_t r; > + > + r = sizeof(field) + sizeof(offset); > + if (r + vmcsinfo_size > vmcsinfo_max_size) > + return; > + > + memcpy(&vmcsinfo_data[vmcsinfo_size], &field, sizeof(field)); > + vmcsinfo_size += sizeof(field); > + memcpy(&vmcsinfo_data[vmcsinfo_size], &offset, sizeof(offset)); > + vmcsinfo_size += sizeof(offset); Instead of this vmcsinfo_data, how about a struct with fields for the revision ID and field count, and an array for the fields? Should be a lot simpler. > +} > +EXPORT_SYMBOL_GPL(vmcsinfo_append_field); > + > +unsigned long paddr_vmcsinfo_note(void) > +{ > + return __pa((unsigned long)(char *)&vmcsinfo_note); > +} > -- error compiling committee.c: too many arguments to function