From patchwork Tue Apr 18 01:33:29 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Blake X-Patchwork-Id: 9684801 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 7E87D6037D for ; Tue, 18 Apr 2017 01:38:20 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6C96C25223 for ; Tue, 18 Apr 2017 01:38:20 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 5EEB327C0B; Tue, 18 Apr 2017 01:38:20 +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 EFD2C25223 for ; Tue, 18 Apr 2017 01:38:19 +0000 (UTC) Received: from localhost ([::1]:39493 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d0I5y-0007X4-ES for patchwork-qemu-devel@patchwork.kernel.org; Mon, 17 Apr 2017 21:38:18 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33925) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d0I25-00058E-3t for qemu-devel@nongnu.org; Mon, 17 Apr 2017 21:34:18 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1d0I23-0003cv-R1 for qemu-devel@nongnu.org; Mon, 17 Apr 2017 21:34:17 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57968) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1d0I1z-0003UR-5B; Mon, 17 Apr 2017 21:34:11 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 23C8780F90; Tue, 18 Apr 2017 01:34:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 23C8780F90 Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=eblake@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 23C8780F90 Received: from red.redhat.com (ovpn-121-102.rdu2.redhat.com [10.10.121.102]) by smtp.corp.redhat.com (Postfix) with ESMTP id EB44A53C35; Tue, 18 Apr 2017 01:34:08 +0000 (UTC) From: Eric Blake To: qemu-devel@nongnu.org Date: Mon, 17 Apr 2017 20:33:29 -0500 Message-Id: <20170418013356.3578-5-eblake@redhat.com> In-Reply-To: <20170418013356.3578-1-eblake@redhat.com> References: <20170418013356.3578-1-eblake@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Tue, 18 Apr 2017 01:34:10 +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 04/31] block: Switch bdrv_make_zero() to byte-based 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 , Fam Zheng , qemu-block@nongnu.org, Max Reitz , Stefan Hajnoczi , kwolf@nongnu.org, jsnow@redhat.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP We are gradually converting to byte-based interfaces, as they are easier to reason about than sector-based. Change the internal loop iteration of zeroing a device to track by bytes instead of sectors (although we are still guaranteed that we iterate by steps that are sector-aligned). Signed-off-by: Eric Blake --- block/io.c | 32 ++++++++++++++++---------------- 1 file changed, 16 insertions(+), 16 deletions(-) diff --git a/block/io.c b/block/io.c index 07165dc..1f8ae81 100644 --- a/block/io.c +++ b/block/io.c @@ -666,39 +666,39 @@ int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset, */ int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags) { - int64_t target_sectors, ret, nb_sectors, sector_num = 0; + int64_t target_size, ret, bytes, offset = 0; BlockDriverState *bs = child->bs; BlockDriverState *file; - int n; + int n; /* sectors */ - target_sectors = bdrv_nb_sectors(bs); - if (target_sectors < 0) { - return target_sectors; + target_size = bdrv_getlength(bs); + if (target_size < 0) { + return target_size; } for (;;) { - nb_sectors = MIN(target_sectors - sector_num, BDRV_REQUEST_MAX_SECTORS); - if (nb_sectors <= 0) { + bytes = MIN(target_size - offset, BDRV_REQUEST_MAX_BYTES); + if (bytes <= 0) { return 0; } - ret = bdrv_get_block_status(bs, sector_num, nb_sectors, &n, &file); + ret = bdrv_get_block_status(bs, offset >> BDRV_SECTOR_BITS, + bytes >> BDRV_SECTOR_BITS, &n, &file); if (ret < 0) { - error_report("error getting block status at sector %" PRId64 ": %s", - sector_num, strerror(-ret)); + error_report("error getting block status at offset %" PRId64 ": %s", + offset, strerror(-ret)); return ret; } if (ret & BDRV_BLOCK_ZERO) { - sector_num += n; + offset += n * BDRV_SECTOR_BITS; continue; } - ret = bdrv_pwrite_zeroes(child, sector_num << BDRV_SECTOR_BITS, - n << BDRV_SECTOR_BITS, flags); + ret = bdrv_pwrite_zeroes(child, offset, n * BDRV_SECTOR_SIZE, flags); if (ret < 0) { - error_report("error writing zeroes at sector %" PRId64 ": %s", - sector_num, strerror(-ret)); + error_report("error writing zeroes at offset %" PRId64 ": %s", + offset, strerror(-ret)); return ret; } - sector_num += n; + offset += n * BDRV_SECTOR_SIZE; } }