{"id":813509,"url":"http://patchwork.ozlabs.org/api/patches/813509/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20170913160333.23622-6-eblake@redhat.com/","project":{"id":14,"url":"http://patchwork.ozlabs.org/api/projects/14/?format=json","name":"QEMU Development","link_name":"qemu-devel","list_id":"qemu-devel.nongnu.org","list_email":"qemu-devel@nongnu.org","web_url":"","scm_url":"","webscm_url":"","list_archive_url":"","list_archive_url_format":"","commit_url_format":""},"msgid":"<20170913160333.23622-6-eblake@redhat.com>","list_archive_url":null,"date":"2017-09-13T16:03:15","name":"[v4,05/23] block: Switch bdrv_make_zero() to byte-based","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"750e45453336ef23ba203b9d78373044e07ffb8f","submitter":{"id":6591,"url":"http://patchwork.ozlabs.org/api/people/6591/?format=json","name":"Eric Blake","email":"eblake@redhat.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20170913160333.23622-6-eblake@redhat.com/mbox/","series":[{"id":2944,"url":"http://patchwork.ozlabs.org/api/series/2944/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/list/?series=2944","date":"2017-09-13T16:03:10","name":"make bdrv_get_block_status byte-based","version":4,"mbox":"http://patchwork.ozlabs.org/series/2944/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/813509/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/813509/checks/","tags":{},"related":[],"headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@bilbo.ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=pass (mailfrom) smtp.mailfrom=nongnu.org\n\t(client-ip=208.118.235.17; helo=lists.gnu.org;\n\tenvelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org;\n\treceiver=)","ext-mx01.extmail.prod.ext.phx2.redhat.com;\n\tdmarc=none (p=none dis=none) header.from=redhat.com","ext-mx01.extmail.prod.ext.phx2.redhat.com;\n\tspf=fail smtp.mailfrom=eblake@redhat.com"],"Received":["from lists.gnu.org (lists.gnu.org [208.118.235.17])\n\t(using TLSv1 with cipher AES256-SHA (256/256 bits))\n\t(No client certificate requested)\n\tby ozlabs.org (Postfix) with ESMTPS id 3xsmnl1RjBz9sNV\n\tfor ;\n\tThu, 14 Sep 2017 02:09:31 +1000 (AEST)","from localhost ([::1]:43369 helo=lists.gnu.org)\n\tby lists.gnu.org with esmtp (Exim 4.71) (envelope-from\n\t)\n\tid 1dsAED-0006o5-6r\n\tfor incoming@patchwork.ozlabs.org; Wed, 13 Sep 2017 12:09:29 -0400","from eggs.gnu.org ([2001:4830:134:3::10]:45580)\n\tby lists.gnu.org with esmtp (Exim 4.71)\n\t(envelope-from ) id 1dsA91-0001EE-OA\n\tfor qemu-devel@nongnu.org; Wed, 13 Sep 2017 12:04:13 -0400","from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)\n\t(envelope-from ) id 1dsA90-0005ul-Nx\n\tfor qemu-devel@nongnu.org; Wed, 13 Sep 2017 12:04:07 -0400","from mx1.redhat.com ([209.132.183.28]:33894)\n\tby eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32)\n\t(Exim 4.71) (envelope-from )\n\tid 1dsA8y-0005sS-6C; Wed, 13 Sep 2017 12:04:04 -0400","from smtp.corp.redhat.com\n\t(int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11])\n\t(using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits))\n\t(No client certificate requested)\n\tby mx1.redhat.com (Postfix) with ESMTPS id 389D981DFC;\n\tWed, 13 Sep 2017 16:04:03 +0000 (UTC)","from red.redhat.com (ovpn-120-201.rdu2.redhat.com [10.10.120.201])\n\tby smtp.corp.redhat.com (Postfix) with ESMTP id 26CD25C6D2;\n\tWed, 13 Sep 2017 16:04:00 +0000 (UTC)"],"DMARC-Filter":"OpenDMARC Filter v1.3.2 mx1.redhat.com 389D981DFC","From":"Eric Blake ","To":"qemu-devel@nongnu.org","Date":"Wed, 13 Sep 2017 11:03:15 -0500","Message-Id":"<20170913160333.23622-6-eblake@redhat.com>","In-Reply-To":"<20170913160333.23622-1-eblake@redhat.com>","References":"<20170913160333.23622-1-eblake@redhat.com>","X-Scanned-By":"MIMEDefang 2.79 on 10.5.11.11","X-Greylist":"Sender IP whitelisted, not delayed by milter-greylist-4.5.16\n\t(mx1.redhat.com [10.5.110.25]);\n\tWed, 13 Sep 2017 16:04:03 +0000 (UTC)","X-detected-operating-system":"by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic]\n\t[fuzzy]","X-Received-From":"209.132.183.28","Subject":"[Qemu-devel] [PATCH v4 05/23] block: Switch bdrv_make_zero() to\n\tbyte-based","X-BeenThere":"qemu-devel@nongnu.org","X-Mailman-Version":"2.1.21","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Cc":"kwolf@redhat.com, famz@redhat.com, qemu-block@nongnu.org,\n\tMax Reitz ,\n\tStefan Hajnoczi , jsnow@redhat.com","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"\"Qemu-devel\"\n\t"},"content":"We are gradually converting to byte-based interfaces, as they are\neasier to reason about than sector-based. Change the internal\nloop iteration of zeroing a device to track by bytes instead of\nsectors (although we are still guaranteed that we iterate by steps\nthat are sector-aligned).\n\nSigned-off-by: Eric Blake \nReviewed-by: Fam Zheng \n\n---\nv3: no change\nv2: rebase to earlier changes\n---\n block/io.c | 32 ++++++++++++++++----------------\n 1 file changed, 16 insertions(+), 16 deletions(-)","diff":"diff --git a/block/io.c b/block/io.c\nindex b362b46e3d..638b3890b7 100644\n--- a/block/io.c\n+++ b/block/io.c\n@@ -693,38 +693,38 @@ int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset,\n */\n int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags)\n {\n- int64_t target_sectors, ret, nb_sectors, sector_num = 0;\n+ int64_t target_size, ret, bytes, offset = 0;\n BlockDriverState *bs = child->bs;\n- int n;\n+ int n; /* sectors */\n\n- target_sectors = bdrv_nb_sectors(bs);\n- if (target_sectors < 0) {\n- return target_sectors;\n+ target_size = bdrv_getlength(bs);\n+ if (target_size < 0) {\n+ return target_size;\n }\n\n for (;;) {\n- nb_sectors = MIN(target_sectors - sector_num, BDRV_REQUEST_MAX_SECTORS);\n- if (nb_sectors <= 0) {\n+ bytes = MIN(target_size - offset, BDRV_REQUEST_MAX_BYTES);\n+ if (bytes <= 0) {\n return 0;\n }\n- ret = bdrv_get_block_status(bs, sector_num, nb_sectors, &n, NULL);\n+ ret = bdrv_get_block_status(bs, offset >> BDRV_SECTOR_BITS,\n+ bytes >> BDRV_SECTOR_BITS, &n, NULL);\n if (ret < 0) {\n- error_report(\"error getting block status at sector %\" PRId64 \": %s\",\n- sector_num, strerror(-ret));\n+ error_report(\"error getting block status at offset %\" PRId64 \": %s\",\n+ offset, strerror(-ret));\n return ret;\n }\n if (ret & BDRV_BLOCK_ZERO) {\n- sector_num += n;\n+ offset += n * BDRV_SECTOR_BITS;\n continue;\n }\n- ret = bdrv_pwrite_zeroes(child, sector_num << BDRV_SECTOR_BITS,\n- n << BDRV_SECTOR_BITS, flags);\n+ ret = bdrv_pwrite_zeroes(child, offset, n * BDRV_SECTOR_SIZE, flags);\n if (ret < 0) {\n- error_report(\"error writing zeroes at sector %\" PRId64 \": %s\",\n- sector_num, strerror(-ret));\n+ error_report(\"error writing zeroes at offset %\" PRId64 \": %s\",\n+ offset, strerror(-ret));\n return ret;\n }\n- sector_num += n;\n+ offset += n * BDRV_SECTOR_SIZE;\n }\n }\n\n","prefixes":["v4","05/23"]}