From mboxrd@z Thu Jan 1 00:00:00 1970 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 53128C83000 for ; Tue, 28 Apr 2020 20:33:35 +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 16B7E206D6 for ; Tue, 28 Apr 2020 20:33:35 +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="KBD/ARtO" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 16B7E206D6 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]:50430 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jTWv8-0007V2-6U for qemu-devel@archiver.kernel.org; Tue, 28 Apr 2020 16:33:34 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:40170) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jTWr5-0000Oq-Or for qemu-devel@nongnu.org; Tue, 28 Apr 2020 16:29:24 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.90_1) (envelope-from ) id 1jTWr5-0005sQ-6g for qemu-devel@nongnu.org; Tue, 28 Apr 2020 16:29:23 -0400 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:23163 helo=us-smtp-delivery-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 1jTWr4-0005r1-N6 for qemu-devel@nongnu.org; Tue, 28 Apr 2020 16:29:22 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1588105762; 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=Sy7muZnbrKhcT5u11YWymKLyj9t4Jbzg6RPGMAlmONs=; b=KBD/ARtOQNSAnyINk6DtSk+fCs9s4c/dz8x2ieldh1gY0pgKDbnQjnyH8bgEeqAFFClwV1 kIcB3yQUjFHBZ8XAxlf4Y9gHPsx6H4PS/ZrjkrJd8Y+vn/J0TRtr7pgnS9HIXOOfaWI5wB gFxYwcyhdAbR/Yrq65w64KkcLSzBVRk= 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-83-h66-C6bxNkWzom0ISka0og-1; Tue, 28 Apr 2020 16:29:20 -0400 X-MC-Unique: h66-C6bxNkWzom0ISka0og-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 6EBCC1895A29; Tue, 28 Apr 2020 20:29:19 +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 E375E5C1D4; Tue, 28 Apr 2020 20:29:15 +0000 (UTC) From: Eric Blake To: qemu-devel@nongnu.org Subject: [PATCH 4/9] rbd: Support BDRV_REQ_ZERO_WRITE for truncate Date: Tue, 28 Apr 2020 15:29:00 -0500 Message-Id: <20200428202905.770727-5-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 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=207.211.31.81; envelope-from=eblake@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/04/28 04:11:46 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.81 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, Jason Dillaman , qemu-block@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Our .bdrv_has_zero_init_truncate always returns 1 because rbd always 0-fills; we can use that same knowledge to implement BDRV_REQ_ZERO_WRITE by ignoring it. Signed-off-by: Eric Blake --- block/rbd.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/block/rbd.c b/block/rbd.c index f2d52091c702..331c45adb2b2 100644 --- a/block/rbd.c +++ b/block/rbd.c @@ -817,6 +817,9 @@ static int qemu_rbd_open(BlockDriverState *bs, QDict *o= ptions, int flags, } } + /* When extending regular files, we get zeros from the OS */ + bs->supported_truncate_flags =3D BDRV_REQ_ZERO_WRITE; + r =3D 0; goto out; --=20 2.26.2