From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60699) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1V4ACQ-0007qp-6z for qemu-devel@nongnu.org; Tue, 30 Jul 2013 09:42:56 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1V4ACJ-00008P-OL for qemu-devel@nongnu.org; Tue, 30 Jul 2013 09:42:50 -0400 Received: from mx1.redhat.com ([209.132.183.28]:23395) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1V4ACJ-000084-Ep for qemu-devel@nongnu.org; Tue, 30 Jul 2013 09:42:43 -0400 Received: from int-mx01.intmail.prod.int.phx2.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r6UDgg5T030062 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Tue, 30 Jul 2013 09:42:42 -0400 Date: Tue, 30 Jul 2013 09:42:39 -0400 From: Jeff Cody Message-ID: <20130730134239.GA19718@localhost.localdomain> References: <803cc31a021f57b4310f133ea5b03e2af7ef7f04.1374687002.git.jcody@redhat.com> <20130730031502.GA9986@T430s.nay.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130730031502.GA9986@T430s.nay.redhat.com> Subject: Re: [Qemu-devel] [PATCH 4/9] block: vhdx - log support struct and defines List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Fam Zheng Cc: kwolf@redhat.com, qemu-devel@nongnu.org, stefanha@redhat.com On Tue, Jul 30, 2013 at 11:15:02AM +0800, Fam Zheng wrote: > On Wed, 07/24 13:54, Jeff Cody wrote: > > This adds some magic number defines, and internal structure > > definitions for VHDX log replay support. > > > > Signed-off-by: Jeff Cody > > --- > > block/vhdx.h | 21 ++++++++++++++++++++- > > 1 file changed, 20 insertions(+), 1 deletion(-) > > > > diff --git a/block/vhdx.h b/block/vhdx.h > > index c8d8593..2db6615 100644 > > --- a/block/vhdx.h > > +++ b/block/vhdx.h > > @@ -151,7 +151,10 @@ typedef struct QEMU_PACKED VHDXRegionTableEntry { > > > > > > /* ---- LOG ENTRY STRUCTURES ---- */ > > +#define VHDX_LOG_MIN_SIZE (1024*1024) > > +#define VHDX_LOG_SECTOR_SIZE 4096 > > #define VHDX_LOG_HDR_SIZE 64 > > +#define VHDX_LOG_SIGNATURE 0x65676f6c > > typedef struct QEMU_PACKED VHDXLogEntryHeader { > > uint32_t signature; /* "loge" in ASCII */ > > uint32_t checksum; /* CRC-32C hash of the 64KB table */ > > @@ -174,7 +177,8 @@ typedef struct QEMU_PACKED VHDXLogEntryHeader { > > } VHDXLogEntryHeader; > > > > #define VHDX_LOG_DESC_SIZE 32 > > - > > +#define VHDX_LOG_DESC_SIGNATURE 0x63736564 > > +#define VHDX_LOG_ZERO_SIGNATURE 0x6f72657a > > Are these macros really used? I see "desc" and "zero" used to compare > signatures. > They are used in the log write patch (when creating new log sectors). Right now, we only create data sectors (nothing uses the zero sectors yet), so only the _DESC_SIGNATURE is used. Thanks, Jeff