{"id":818289,"url":"http://patchwork.ozlabs.org/api/patches/818289/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20170925145526.32690-6-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":"<20170925145526.32690-6-eblake@redhat.com>","list_archive_url":null,"date":"2017-09-25T14:55:11","name":"[v10,05/20] dirty-bitmap: Avoid size query failure during truncate","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"814eb2c47329f8e8adda05a13337085c8d90928d","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/20170925145526.32690-6-eblake@redhat.com/mbox/","series":[{"id":4978,"url":"http://patchwork.ozlabs.org/api/series/4978/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/list/?series=4978","date":"2017-09-25T14:55:06","name":"make dirty-bitmap byte-based","version":10,"mbox":"http://patchwork.ozlabs.org/series/4978/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/818289/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/818289/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=2001:4830:134:3::11; helo=lists.gnu.org;\n\tenvelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org;\n\treceiver=)","ext-mx05.extmail.prod.ext.phx2.redhat.com;\n\tdmarc=none (p=none dis=none) header.from=redhat.com","ext-mx05.extmail.prod.ext.phx2.redhat.com;\n\tspf=fail smtp.mailfrom=eblake@redhat.com"],"Received":["from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11])\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 3y16nr141dz9t67\n\tfor ;\n\tTue, 26 Sep 2017 01:05:04 +1000 (AEST)","from localhost ([::1]:42877 helo=lists.gnu.org)\n\tby lists.gnu.org with esmtp (Exim 4.71) (envelope-from\n\t)\n\tid 1dwUwQ-00063C-61\n\tfor incoming@patchwork.ozlabs.org; Mon, 25 Sep 2017 11:05:02 -0400","from eggs.gnu.org ([2001:4830:134:3::10]:54116)\n\tby lists.gnu.org with esmtp (Exim 4.71)\n\t(envelope-from ) id 1dwUnv-0005u3-Lw\n\tfor qemu-devel@nongnu.org; Mon, 25 Sep 2017 10:56:16 -0400","from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)\n\t(envelope-from ) id 1dwUnu-0003Ht-IJ\n\tfor qemu-devel@nongnu.org; Mon, 25 Sep 2017 10:56:15 -0400","from mx1.redhat.com ([209.132.183.28]:35182)\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 1dwUnq-0003G3-NI; Mon, 25 Sep 2017 10:56:10 -0400","from smtp.corp.redhat.com\n\t(int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13])\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 A2F892CE910;\n\tMon, 25 Sep 2017 14:56:09 +0000 (UTC)","from red.redhat.com (ovpn-124-97.rdu2.redhat.com [10.10.124.97])\n\tby smtp.corp.redhat.com (Postfix) with ESMTP id BED047AA70;\n\tMon, 25 Sep 2017 14:56:05 +0000 (UTC)"],"DMARC-Filter":"OpenDMARC Filter v1.3.2 mx1.redhat.com A2F892CE910","From":"Eric Blake ","To":"qemu-devel@nongnu.org","Date":"Mon, 25 Sep 2017 09:55:11 -0500","Message-Id":"<20170925145526.32690-6-eblake@redhat.com>","In-Reply-To":"<20170925145526.32690-1-eblake@redhat.com>","References":"<20170925145526.32690-1-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\n\t(mx1.redhat.com [10.5.110.29]);\n\tMon, 25 Sep 2017 14:56:09 +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 v10 05/20] dirty-bitmap: Avoid size query\n\tfailure during truncate","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, vsementsov@virtuozzo.com, famz@redhat.com,\n\tqemu-block@nongnu.org, Max Reitz , jsnow@redhat.com","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"\"Qemu-devel\"\n\t"},"content":"We've previously fixed several places where we failed to account\nfor possible errors from bdrv_nb_sectors(). Fix another one by\nmaking bdrv_dirty_bitmap_truncate() take the new size from the\ncaller instead of querying itself; then adjust the sole caller\nbdrv_truncate() to pass the size just determined by a successful\nresize, or to skip the bitmap resize on failure, thus avoiding\nsizing the bitmaps to -1. This also fixes a bug where not all\nfailure paths in bdrv_truncate() would set errp.\n\nNote that bdrv_truncate() is still a bit awkward. We may want\nto revisit it later and clean up things to better guarantee that\na resize attempt either fails cleanly up front, or cannot fail\nafter guest-visible changes have been made (if temporary changes\nare made, then they need to be cleanly rolled back). But that\nis a task for another day; for now, the goal is the bare minimum\nfix to ensure that just bdrv_dirty_bitmap_truncate() cannot fail.\n\nSigned-off-by: Eric Blake \n\n---\nv10: always resize bitmap as before [John], enhance commit message to\npoint out errp bugfix [Vladimir]\nv9: skip only bdrv_dirty_bitmap_truncate on error [Fam]\nv8: retitle and rework to avoid possibility of secondary failure [John]\nv7: new patch [Kevin]\n---\n include/block/dirty-bitmap.h | 2 +-\n block.c | 16 +++++++++++-----\n block/dirty-bitmap.c | 6 +++---\n 3 files changed, 15 insertions(+), 9 deletions(-)","diff":"diff --git a/include/block/dirty-bitmap.h b/include/block/dirty-bitmap.h\nindex 8fd842eac9..7a27590047 100644\n--- a/include/block/dirty-bitmap.h\n+++ b/include/block/dirty-bitmap.h\n@@ -83,7 +83,7 @@ int64_t bdrv_dirty_iter_next(BdrvDirtyBitmapIter *iter);\n void bdrv_set_dirty_iter(BdrvDirtyBitmapIter *hbi, int64_t sector_num);\n int64_t bdrv_get_dirty_count(BdrvDirtyBitmap *bitmap);\n int64_t bdrv_get_meta_dirty_count(BdrvDirtyBitmap *bitmap);\n-void bdrv_dirty_bitmap_truncate(BlockDriverState *bs);\n+void bdrv_dirty_bitmap_truncate(BlockDriverState *bs, int64_t bytes);\n bool bdrv_dirty_bitmap_readonly(const BdrvDirtyBitmap *bitmap);\n bool bdrv_has_readonly_bitmaps(BlockDriverState *bs);\n bool bdrv_dirty_bitmap_get_autoload(const BdrvDirtyBitmap *bitmap);\ndiff --git a/block.c b/block.c\nindex 528cda7b2c..ef5af81f66 100644\n--- a/block.c\n+++ b/block.c\n@@ -3545,12 +3545,18 @@ int bdrv_truncate(BdrvChild *child, int64_t offset, PreallocMode prealloc,\n assert(!(bs->open_flags & BDRV_O_INACTIVE));\n\n ret = drv->bdrv_truncate(bs, offset, prealloc, errp);\n- if (ret == 0) {\n- ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS);\n- bdrv_dirty_bitmap_truncate(bs);\n- bdrv_parent_cb_resize(bs);\n- atomic_inc(&bs->write_gen);\n+ if (ret < 0) {\n+ return ret;\n }\n+ ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS);\n+ if (ret < 0) {\n+ error_setg_errno(errp, -ret, \"Could not refresh total sector count\");\n+ } else {\n+ offset = bs->total_sectors * BDRV_SECTOR_SIZE;\n+ }\n+ bdrv_dirty_bitmap_truncate(bs, offset);\n+ bdrv_parent_cb_resize(bs);\n+ atomic_inc(&bs->write_gen);\n return ret;\n }\n\ndiff --git a/block/dirty-bitmap.c b/block/dirty-bitmap.c\nindex 42a55e4a4b..ee164fb518 100644\n--- a/block/dirty-bitmap.c\n+++ b/block/dirty-bitmap.c\n@@ -1,7 +1,7 @@\n /*\n * Block Dirty Bitmap\n *\n- * Copyright (c) 2016 Red Hat. Inc\n+ * Copyright (c) 2016-2017 Red Hat. Inc\n *\n * Permission is hereby granted, free of charge, to any person obtaining a copy\n * of this software and associated documentation files (the \"Software\"), to deal\n@@ -302,10 +302,10 @@ BdrvDirtyBitmap *bdrv_reclaim_dirty_bitmap(BlockDriverState *bs,\n * Truncates _all_ bitmaps attached to a BDS.\n * Called with BQL taken.\n */\n-void bdrv_dirty_bitmap_truncate(BlockDriverState *bs)\n+void bdrv_dirty_bitmap_truncate(BlockDriverState *bs, int64_t bytes)\n {\n BdrvDirtyBitmap *bitmap;\n- uint64_t size = bdrv_nb_sectors(bs);\n+ int64_t size = DIV_ROUND_UP(bytes, BDRV_SECTOR_SIZE);\n\n bdrv_dirty_bitmaps_lock(bs);\n QLIST_FOREACH(bitmap, &bs->dirty_bitmaps, list) {\n","prefixes":["v10","05/20"]}