From nobody Tue Feb 10 04:13:51 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1588106147; cv=none; d=zohomail.com; s=zohoarc; b=ifsV8ayhho039kNQNyEBmENBrC6ZsSm6LaaNKKBWe3UWclWnJ+/6+r3aIz9aTN/kcB85dM6SCCGSz+a8HEz3AJ3sZFvLspZ7TWk0xIws5MCYvFub2fGAVjr/ZlDG+Zex9MTGjUk0dJpxQvbj8mkR953ABTjzhKEtIc7LHPGQCiE= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1588106147; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=wiJtkm4BOPlkfyJYqkgh9TApAzazKeM4pdRoyO6Os24=; b=GoNpC67yWwnoH8NnwVJiSUzI8pL+m2f4iQGD0wZiVghn+2UTwaglXv+mYw3VYWJIBXteXZfUlrVHBZLy699FwsMsRFz541CsxzDyu6DWT8TwJy/AgdBZXCy1K1ws/dLpW6pBgKnOG+sALs2HkpvQmo0lNyrpuTRjXEI272i9nFA= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1588106147696340.74089584463115; Tue, 28 Apr 2020 13:35:47 -0700 (PDT) Received: from localhost ([::1]:50640 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jTWxG-0003e4-Ef for importer@patchew.org; Tue, 28 Apr 2020 16:35:46 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:40246) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jTWrG-0000rk-3x for qemu-devel@nongnu.org; Tue, 28 Apr 2020 16:29:37 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.90_1) (envelope-from ) id 1jTWrD-0006Ey-Lb for qemu-devel@nongnu.org; Tue, 28 Apr 2020 16:29:33 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:35608 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 1jTWrD-0006Ei-77 for qemu-devel@nongnu.org; Tue, 28 Apr 2020 16:29:31 -0400 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-206-EOKi1xUdOG63Q-8u6Atjhw-1; Tue, 28 Apr 2020 16:29:27 -0400 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 F29DD835B44; Tue, 28 Apr 2020 20:29:25 +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 3E63D5C1D4; Tue, 28 Apr 2020 20:29:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1588105770; 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=wiJtkm4BOPlkfyJYqkgh9TApAzazKeM4pdRoyO6Os24=; b=GSiYuDPY/bvckoAE7m0zUE/m3kA3aYoSArmsY8UDmlF7nfpTk+ent+rdCTwsYqtt6AE5me 7Ht4vlPIG9niYkdvLeukRDQ49i/EMXkHgEvHlsRzSErx/pCyhGuDybhB+uti5vXwZHb341 G2HNcv+uA/L6HzGCvhX8EeQ7ocwbLqs= X-MC-Unique: EOKi1xUdOG63Q-8u6Atjhw-1 From: Eric Blake To: qemu-devel@nongnu.org Subject: [PATCH 7/9] parallels: Rework truncation logic Date: Tue, 28 Apr 2020 15:29:03 -0500 Message-Id: <20200428202905.770727-8-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-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=205.139.110.120; envelope-from=eblake@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/04/28 02:16:38 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] X-Received-From: 205.139.110.120 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, "Denis V. Lunev" , Stefan Hajnoczi , qemu-block@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) Content-Type: text/plain; charset="utf-8" The parallels driver tries to use truncation for image growth, but can only do so when reads are guaranteed as zero. Now that we have a way to request zero contents from truncation, we can defer the decision to actual allocation attempts rather than up front, reducing the number of places that still use bdrv_has_zero_init_truncate. Signed-off-by: Eric Blake Reviewed-by: Denis V. Lunev --- block/parallels.c | 23 +++++++++++++++-------- 1 file changed, 15 insertions(+), 8 deletions(-) diff --git a/block/parallels.c b/block/parallels.c index 2be92cf41708..9dadaa3217b9 100644 --- a/block/parallels.c +++ b/block/parallels.c @@ -196,14 +196,24 @@ static int64_t allocate_clusters(BlockDriverState *bs= , int64_t sector_num, } if (s->data_end + space > (len >> BDRV_SECTOR_BITS)) { space +=3D s->prealloc_size; + /* + * We require the expanded size to read back as zero. If the + * user permitted truncation, we try that; but if it fails, we + * force the safer-but-slower fallocate. + */ + if (s->prealloc_mode =3D=3D PRL_PREALLOC_MODE_TRUNCATE) { + ret =3D bdrv_truncate(bs->file, + (s->data_end + space) << BDRV_SECTOR_BITS, + false, PREALLOC_MODE_OFF, BDRV_REQ_ZERO_WR= ITE, + NULL); + if (ret =3D=3D -ENOTSUP) { + s->prealloc_mode =3D PRL_PREALLOC_MODE_FALLOCATE; + } + } if (s->prealloc_mode =3D=3D PRL_PREALLOC_MODE_FALLOCATE) { ret =3D bdrv_pwrite_zeroes(bs->file, s->data_end << BDRV_SECTOR_BITS, space << BDRV_SECTOR_BITS, 0); - } else { - ret =3D bdrv_truncate(bs->file, - (s->data_end + space) << BDRV_SECTOR_BITS, - false, PREALLOC_MODE_OFF, 0, NULL); } if (ret < 0) { return ret; @@ -828,6 +838,7 @@ static int parallels_open(BlockDriverState *bs, QDict *= options, int flags, qemu_opt_get_size_del(opts, PARALLELS_OPT_PREALLOC_SIZE, 0); s->prealloc_size =3D MAX(s->tracks, s->prealloc_size >> BDRV_SECTOR_BI= TS); buf =3D qemu_opt_get_del(opts, PARALLELS_OPT_PREALLOC_MODE); + /* prealloc_mode can be downgraded later during allocate_clusters */ s->prealloc_mode =3D qapi_enum_parse(&prealloc_mode_lookup, buf, PRL_PREALLOC_MODE_FALLOCATE, &local_err); @@ -836,10 +847,6 @@ static int parallels_open(BlockDriverState *bs, QDict = *options, int flags, goto fail_options; } - if (!bdrv_has_zero_init_truncate(bs->file->bs)) { - s->prealloc_mode =3D PRL_PREALLOC_MODE_FALLOCATE; - } - if ((flags & BDRV_O_RDWR) && !(flags & BDRV_O_INACTIVE)) { s->header->inuse =3D cpu_to_le32(HEADER_INUSE_MAGIC); ret =3D parallels_update_header(bs); --=20 2.26.2