From patchwork Mon Apr 3 16:09:30 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Max Reitz X-Patchwork-Id: 9659933 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 5F68460352 for ; Mon, 3 Apr 2017 16:16:01 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5102B27FA8 for ; Mon, 3 Apr 2017 16:16:01 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 44C1D2833B; Mon, 3 Apr 2017 16:16:01 +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 E60A627FA8 for ; Mon, 3 Apr 2017 16:16:00 +0000 (UTC) Received: from localhost ([::1]:60153 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cv4e7-0005Ci-UI for patchwork-qemu-devel@patchwork.kernel.org; Mon, 03 Apr 2017 12:16:00 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:34465) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cv4Ym-0001Ht-Ux for qemu-devel@nongnu.org; Mon, 03 Apr 2017 12:10:30 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cv4Ym-0000R8-1h for qemu-devel@nongnu.org; Mon, 03 Apr 2017 12:10:28 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51672) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cv4Yi-0000OV-7u; Mon, 03 Apr 2017 12:10:24 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 4597EC04B927; Mon, 3 Apr 2017 16:10:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 4597EC04B927 Authentication-Results: ext-mx07.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx07.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=mreitz@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 4597EC04B927 Received: from localhost (ovpn-204-55.brq.redhat.com [10.40.204.55]) by smtp.corp.redhat.com (Postfix) with ESMTPS id AF55C18516; Mon, 3 Apr 2017 16:10:20 +0000 (UTC) From: Max Reitz To: qemu-block@nongnu.org Date: Mon, 3 Apr 2017 18:09:30 +0200 Message-Id: <20170403160936.28293-11-mreitz@redhat.com> In-Reply-To: <20170403160936.28293-1-mreitz@redhat.com> References: <20170403160936.28293-1-mreitz@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Mon, 03 Apr 2017 16:10:23 +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 v2 for-2.10 10/16] block/qcow2: Lock s->lock in 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 preallocate() is and will be called only from places that do not lock s->lock: Currently that is qcow2_create2(), as of a future patch it will be called from qcow2_truncate(), too. It therefore makes sense to move locking that mutex into preallocate() itself. Signed-off-by: Max Reitz Reviewed-by: Stefan Hajnoczi --- block/qcow2.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/block/qcow2.c b/block/qcow2.c index 163d51ec65..f665cd21dc 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -2043,12 +2043,15 @@ static int qcow2_change_backing_file(BlockDriverState *bs, */ static int preallocate(BlockDriverState *bs, int64_t offset, int64_t new_length) { + BDRVQcow2State *s = bs->opaque; uint64_t bytes; uint64_t host_offset = 0; unsigned int cur_bytes; int ret; QCowL2Meta *meta; + qemu_co_mutex_lock(&s->lock); + assert(offset <= new_length); bytes = new_length - offset; @@ -2057,7 +2060,7 @@ static int preallocate(BlockDriverState *bs, int64_t offset, int64_t new_length) ret = qcow2_alloc_cluster_offset(bs, offset, &cur_bytes, &host_offset, &meta); if (ret < 0) { - return ret; + goto done; } while (meta) { @@ -2067,7 +2070,7 @@ static int preallocate(BlockDriverState *bs, int64_t offset, int64_t new_length) if (ret < 0) { qcow2_free_any_clusters(bs, meta->alloc_offset, meta->nb_clusters, QCOW2_DISCARD_NEVER); - return ret; + goto done; } /* There are no dependent requests, but we need to remove our @@ -2094,11 +2097,15 @@ static int preallocate(BlockDriverState *bs, int64_t offset, int64_t new_length) ret = bdrv_pwrite(bs->file, (host_offset + cur_bytes) - 1, &data, 1); if (ret < 0) { - return ret; + goto done; } } - return 0; + ret = 0; + +done: + qemu_co_mutex_unlock(&s->lock); + return ret; } static int qcow2_create2(const char *filename, int64_t total_size, @@ -2318,10 +2325,7 @@ static int qcow2_create2(const char *filename, int64_t total_size, /* And if we're supposed to preallocate metadata, do that now */ if (prealloc != PREALLOC_MODE_OFF) { - BDRVQcow2State *s = blk_bs(blk)->opaque; - qemu_co_mutex_lock(&s->lock); 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"); goto out;