From patchwork Tue Mar 27 00:22:10 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marcelo Tosatti X-Patchwork-Id: 148846 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 87009B6EF3 for ; Tue, 27 Mar 2012 11:25:41 +1100 (EST) Received: from localhost ([::1]:34571 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SCKEC-0001Ll-NZ for incoming@patchwork.ozlabs.org; Mon, 26 Mar 2012 20:25:36 -0400 Received: from eggs.gnu.org ([208.118.235.92]:57460) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SCKE5-0001LD-Qr for qemu-devel@nongnu.org; Mon, 26 Mar 2012 20:25:31 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SCKE3-00040l-Sq for qemu-devel@nongnu.org; Mon, 26 Mar 2012 20:25:29 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51413) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SCKE3-00040O-L6 for qemu-devel@nongnu.org; Mon, 26 Mar 2012 20:25:27 -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 q2R0POMK008999 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Mon, 26 Mar 2012 20:25:24 -0400 Received: from amt.cnet (vpn1-6-157.ams2.redhat.com [10.36.6.157]) by int-mx01.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id q2R0PMQ4031745; Mon, 26 Mar 2012 20:25:23 -0400 Received: from amt.cnet (amt.cnet [127.0.0.1]) by amt.cnet (Postfix) with ESMTP id 7EE2A66E148; Mon, 26 Mar 2012 21:22:12 -0300 (BRT) Received: (from marcelo@localhost) by amt.cnet (8.14.5/8.14.5/Submit) id q2R0MAVb008411; Mon, 26 Mar 2012 21:22:10 -0300 Date: Mon, 26 Mar 2012 21:22:10 -0300 From: Marcelo Tosatti To: Stefan Hajnoczi , Kevin Wolf Message-ID: <20120327002210.GB8343@amt.cnet> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) X-Scanned-By: MIMEDefang 2.67 on 10.5.11.11 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 209.132.183.28 Cc: qemu-devel@nongnu.org Subject: [Qemu-devel] [PATCH v2] block stream: close unused files and update ->backing_hd X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Close the now unused images that were part of the previous backing file chain and adjust ->backing_hd, backing_filename and backing_format properly. Fixes https://bugzilla.redhat.com/show_bug.cgi?id=801449 Signed-off-by: Marcelo Tosatti Reviewed-by: Stefan Hajnoczi diff --git a/block/stream.c b/block/stream.c index d1b3986..5880288 100644 --- a/block/stream.c +++ b/block/stream.c @@ -76,6 +76,39 @@ static int coroutine_fn stream_populate(BlockDriverState *bs, return bdrv_co_copy_on_readv(bs, sector_num, nb_sectors, &qiov); } +static void close_unused_images(BlockDriverState *top, BlockDriverState *base, + const char *base_id) +{ + BlockDriverState *intermediate; + intermediate = top->backing_hd; + + while (intermediate) { + BlockDriverState *unused; + + /* reached base */ + if (intermediate == base) { + break; + } + + unused = intermediate; + intermediate = intermediate->backing_hd; + unused->backing_hd = NULL; + bdrv_delete(unused); + } + top->backing_hd = base; + + pstrcpy(top->backing_file, sizeof(top->backing_file), ""); + pstrcpy(top->backing_format, sizeof(top->backing_format), ""); + if (base_id) { + pstrcpy(top->backing_file, sizeof(top->backing_file), base_id); + if (base->drv) { + pstrcpy(top->backing_format, sizeof(top->backing_format), + base->drv->format_name); + } + } + +} + /* * Given an image chain: [BASE] -> [INTER1] -> [INTER2] -> [TOP] * @@ -221,6 +254,7 @@ retry: base_id = s->backing_file_id; } ret = bdrv_change_backing_file(bs, base_id, NULL); + close_unused_images(bs, base, base_id); } qemu_vfree(buf);