From patchwork Tue Jun 15 14:19:25 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 55677 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [199.232.76.165]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 1027DB7D80 for ; Wed, 16 Jun 2010 00:35:07 +1000 (EST) Received: from localhost ([127.0.0.1]:45734 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OOXED-0007Xc-BH for incoming@patchwork.ozlabs.org; Tue, 15 Jun 2010 10:35:01 -0400 Received: from [140.186.70.92] (port=37705 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OOWzh-0007xA-Q1 for qemu-devel@nongnu.org; Tue, 15 Jun 2010 10:20:02 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1OOWzg-0008WS-P3 for qemu-devel@nongnu.org; Tue, 15 Jun 2010 10:20:01 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51191) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1OOWzg-0008WH-Hq for qemu-devel@nongnu.org; Tue, 15 Jun 2010 10:20:00 -0400 Received: from int-mx04.intmail.prod.int.phx2.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.17]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o5FEJwhe012894 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Tue, 15 Jun 2010 10:19:58 -0400 Received: from localhost.localdomain (dhcp-5-217.str.redhat.com [10.32.5.217]) by int-mx04.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id o5FEJq6q025060; Tue, 15 Jun 2010 10:19:56 -0400 From: Kevin Wolf To: anthony@codemonkey.ws Date: Tue, 15 Jun 2010 16:19:25 +0200 Message-Id: <1276611581-3757-4-git-send-email-kwolf@redhat.com> In-Reply-To: <1276611581-3757-1-git-send-email-kwolf@redhat.com> References: <1276611581-3757-1-git-send-email-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.67 on 10.5.11.17 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. Cc: kwolf@redhat.com, qemu-devel@nongnu.org Subject: [Qemu-devel] [PATCH 03/19] qcow2: Allow alloc_clusters_noref to return errors X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Currently it would consider blocks for which get_refcount fails used. However, it's unlikely that get_refcount would succeed for the next cluster, so it's not really helpful. Return an error instead. Signed-off-by: Kevin Wolf --- block/qcow2-refcount.c | 18 +++++++++++++++--- 1 files changed, 15 insertions(+), 3 deletions(-) diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index ca6b373..51948ae 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -228,7 +228,10 @@ static int64_t alloc_refcount_block(BlockDriverState *bs, int64_t cluster_index) } /* Allocate the refcount block itself and mark it as used */ - uint64_t new_block = alloc_clusters_noref(bs, s->cluster_size); + int64_t new_block = alloc_clusters_noref(bs, s->cluster_size); + if (new_block < 0) { + return new_block; + } #ifdef DEBUG_ALLOC2 fprintf(stderr, "qcow2: Allocate refcount block %d for %" PRIx64 @@ -579,14 +582,19 @@ static int update_cluster_refcount(BlockDriverState *bs, static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size) { BDRVQcowState *s = bs->opaque; - int i, nb_clusters; + int i, nb_clusters, refcount; nb_clusters = size_to_clusters(s, size); retry: for(i = 0; i < nb_clusters; i++) { int64_t next_cluster_index = s->free_cluster_index++; - if (get_refcount(bs, next_cluster_index) != 0) + refcount = get_refcount(bs, next_cluster_index); + + if (refcount < 0) { + return refcount; + } else if (refcount != 0) { goto retry; + } } #ifdef DEBUG_ALLOC2 printf("alloc_clusters: size=%" PRId64 " -> %" PRId64 "\n", @@ -603,6 +611,10 @@ int64_t qcow2_alloc_clusters(BlockDriverState *bs, int64_t size) BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC); offset = alloc_clusters_noref(bs, size); + if (offset < 0) { + return offset; + } + ret = update_refcount(bs, offset, size, 1); if (ret < 0) { return ret;