From patchwork Tue Jun 13 20:21:00 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Max Reitz X-Patchwork-Id: 9784613 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id C518660212 for ; Tue, 13 Jun 2017 20:30:00 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B795D28584 for ; Tue, 13 Jun 2017 20:30:00 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id AC1B728726; Tue, 13 Jun 2017 20:30:00 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 569E128584 for ; Tue, 13 Jun 2017 20:30:00 +0000 (UTC) Received: from localhost ([::1]:45079 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dKsRr-0004gl-DQ for patchwork-qemu-devel@patchwork.kernel.org; Tue, 13 Jun 2017 16:29:59 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38100) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dKsJy-0006RI-6M for qemu-devel@nongnu.org; Tue, 13 Jun 2017 16:21:51 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dKsJx-0001cK-CY for qemu-devel@nongnu.org; Tue, 13 Jun 2017 16:21:50 -0400 Received: from mx1.redhat.com ([209.132.183.28]:60250) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dKsJv-0001b6-00; Tue, 13 Jun 2017 16:21:47 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 0D54680E4A; Tue, 13 Jun 2017 20:21:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 0D54680E4A Authentication-Results: ext-mx01.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx01.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=mreitz@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 0D54680E4A Received: from localhost (ovpn-204-68.brq.redhat.com [10.40.204.68]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 8555651DFC; Tue, 13 Jun 2017 20:21:45 +0000 (UTC) From: Max Reitz To: qemu-block@nongnu.org Date: Tue, 13 Jun 2017 22:21:00 +0200 Message-Id: <20170613202107.10125-10-mreitz@redhat.com> In-Reply-To: <20170613202107.10125-1-mreitz@redhat.com> References: <20170613202107.10125-1-mreitz@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Tue, 13 Jun 2017 20:21:46 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v4 09/16] block/qcow2: Generalize preallocate() X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , qemu-devel@nongnu.org, Stefan Hajnoczi , Max Reitz Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP This patch adds two new parameters to the preallocate() function so we will be able to use it not just for preallocating a new image but also for preallocated image growth. The offset parameter allows the caller to specify a virtual offset from which to start preallocating. For newly created images this is always 0, but for preallocating growth this will be the old image length. The new_length parameter specifies the supposed new length of the image (basically the "end offset" for preallocation). During image truncation, bdrv_getlength() will return the old image length so we cannot rely on its return value then. Signed-off-by: Max Reitz Reviewed-by: Eric Blake Reviewed-by: Stefan Hajnoczi --- block/qcow2.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/block/qcow2.c b/block/qcow2.c index 6371c32..7d201bb 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -2035,17 +2035,24 @@ static int qcow2_change_backing_file(BlockDriverState *bs, return qcow2_update_header(bs); } -static int preallocate(BlockDriverState *bs) +/** + * Preallocates metadata structures for data clusters between @offset (in the + * guest disk) and @new_length (which is thus generally the new guest disk + * size). + * + * Returns: 0 on success, -errno on failure. + */ +static int preallocate(BlockDriverState *bs, + uint64_t offset, uint64_t new_length) { uint64_t bytes; - uint64_t offset; uint64_t host_offset = 0; unsigned int cur_bytes; int ret; QCowL2Meta *meta; - bytes = bdrv_getlength(bs); - offset = 0; + assert(offset <= new_length); + bytes = new_length - offset; while (bytes) { cur_bytes = MIN(bytes, INT_MAX); @@ -2384,7 +2391,7 @@ static int qcow2_create2(const char *filename, int64_t total_size, if (prealloc != PREALLOC_MODE_OFF) { BDRVQcow2State *s = blk_bs(blk)->opaque; qemu_co_mutex_lock(&s->lock); - ret = preallocate(blk_bs(blk)); + ret = preallocate(blk_bs(blk), 0, total_size); qemu_co_mutex_unlock(&s->lock); if (ret < 0) { error_setg_errno(errp, -ret, "Could not preallocate metadata");