From patchwork Tue Apr 28 20:28:58 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Blake X-Patchwork-Id: 283838 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8DA90C83000 for ; Tue, 28 Apr 2020 20:30:46 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 57FB920731 for ; Tue, 28 Apr 2020 20:30:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="YpuUE2bQ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 57FB920731 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:50198 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jTWsP-0002dX-6T for qemu-devel@archiver.kernel.org; Tue, 28 Apr 2020 16:30:45 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:40122) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jTWr1-0000ET-3Y for qemu-devel@nongnu.org; Tue, 28 Apr 2020 16:29:21 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.90_1) (envelope-from ) id 1jTWr0-0005kP-Jn for qemu-devel@nongnu.org; Tue, 28 Apr 2020 16:29:18 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:49912 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jTWr0-0005iX-6H for qemu-devel@nongnu.org; Tue, 28 Apr 2020 16:29:18 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1588105757; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=wJ+p/tqLELPqYN/8ikEj31uiPglzD75NYSwEpqgn92s=; b=YpuUE2bQQW02LWhYNSkPk2tYJyyvkifKWUR2IQBtfc0p6kJ5Bu2pwXOs23v8xb3jORlvYE WUSVPZ9if9WaPQyx0plLjfT3OFlhJcF8MZZ3QdC738NTUmypM1r5zeRvIrfFOclUx6Zuj5 E2ThKNS+IeZQpAbym65CTrSMvFHfK4g= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-503-GLn_P-S2N6usvhjDhbpiyg-1; Tue, 28 Apr 2020 16:29:15 -0400 X-MC-Unique: GLn_P-S2N6usvhjDhbpiyg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 47B15800D24; Tue, 28 Apr 2020 20:29:14 +0000 (UTC) Received: from blue.redhat.com (ovpn-116-80.rdu2.redhat.com [10.10.116.80]) by smtp.corp.redhat.com (Postfix) with ESMTP id 673425C221; Tue, 28 Apr 2020 20:29:13 +0000 (UTC) From: Eric Blake To: qemu-devel@nongnu.org Subject: [PATCH 2/9] file-win32: Support BDRV_REQ_ZERO_WRITE for truncate Date: Tue, 28 Apr 2020 15:28:58 -0500 Message-Id: <20200428202905.770727-3-eblake@redhat.com> In-Reply-To: <20200428202905.770727-1-eblake@redhat.com> References: <20200428202905.770727-1-eblake@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=207.211.31.120; envelope-from=eblake@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/04/28 04:15:05 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.120 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, Stefan Weil , qemu-block@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" When using bdrv_file, .bdrv_has_zero_init_truncate always returns 1; therefore, we can behave just like file-posix, and always implement BDRV_REQ_ZERO_WRITE by ignoring it since the OS gives it to us for free (note that file-posix.c had to use an 'if' because it shared code between regular files and block devices, but in file-win32.c, bdrv_host_device uses a separate .bdrv_file_open). Signed-off-by: Eric Blake --- block/file-win32.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/block/file-win32.c b/block/file-win32.c index a6b0dda5c302..fa569685d8bc 100644 --- a/block/file-win32.c +++ b/block/file-win32.c @@ -408,6 +408,9 @@ static int raw_open(BlockDriverState *bs, QDict *options, int flags, win32_aio_attach_aio_context(s->aio, bdrv_get_aio_context(bs)); } + /* When extending regular files, we get zeros from the OS */ + bs->supported_truncate_flags = BDRV_REQ_ZERO_WRITE; + ret = 0; fail: qemu_opts_del(opts);