From patchwork Thu Jul 13 01:05:52 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Blake X-Patchwork-Id: 787483 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org 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 ozlabs.org (Postfix) with ESMTPS id 3x7Hw430TSz9ryk for ; Thu, 13 Jul 2017 11:16:36 +1000 (AEST) Received: from localhost ([::1]:56715 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dVSk6-0005xc-90 for incoming@patchwork.ozlabs.org; Wed, 12 Jul 2017 21:16:34 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37305) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dVSaU-0005JJ-UL for qemu-devel@nongnu.org; Wed, 12 Jul 2017 21:06:39 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dVSaQ-0001tn-BW for qemu-devel@nongnu.org; Wed, 12 Jul 2017 21:06:38 -0400 Received: from mx1.redhat.com ([209.132.183.28]:33418) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dVSaO-0001ri-44; Wed, 12 Jul 2017 21:06:32 -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 1ADA77F3E5; Thu, 13 Jul 2017 01:06:31 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 1ADA77F3E5 Authentication-Results: ext-mx01.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx01.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=eblake@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 1ADA77F3E5 Received: from red.redhat.com (ovpn-121-60.rdu2.redhat.com [10.10.121.60]) by smtp.corp.redhat.com (Postfix) with ESMTP id BB19A6E531; Thu, 13 Jul 2017 01:06:29 +0000 (UTC) From: Eric Blake To: qemu-devel@nongnu.org Date: Wed, 12 Jul 2017 20:05:52 -0500 Message-Id: <20170713010555.6769-16-eblake@redhat.com> In-Reply-To: <20170713010555.6769-1-eblake@redhat.com> References: <20170713010555.6769-1-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 [10.5.110.25]); Thu, 13 Jul 2017 01:06:31 +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 v5 15/18] qcow2: Switch load_bitmap_data() to byte-based iteration 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: kwolf@redhat.com, vsementsov@virtuozzo.com, jsnow@redhat.com, qemu-block@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" Now that we have adjusted the majority of the calls this function makes to be byte-based, it is easier to read the code if it makes passes over the image using bytes rather than sectors. Signed-off-by: Eric Blake Reviewed-by: John Snow Reviewed-by: Vladimir Sementsov-Ogievskiy --- v5: no change v4: new patch --- block/qcow2-bitmap.c | 22 ++++++++-------------- 1 file changed, 8 insertions(+), 14 deletions(-) diff --git a/block/qcow2-bitmap.c b/block/qcow2-bitmap.c index 5540fba..c44cf78 100644 --- a/block/qcow2-bitmap.c +++ b/block/qcow2-bitmap.c @@ -291,9 +291,8 @@ static int load_bitmap_data(BlockDriverState *bs, { int ret = 0; BDRVQcow2State *s = bs->opaque; - uint64_t sector, limit, sbc; + uint64_t offset, limit; uint64_t bm_size = bdrv_dirty_bitmap_size(bitmap); - uint64_t bm_sectors = DIV_ROUND_UP(bm_size, BDRV_SECTOR_SIZE); uint8_t *buf = NULL; uint64_t i, tab_size = size_to_clusters(s, @@ -305,32 +304,27 @@ static int load_bitmap_data(BlockDriverState *bs, buf = g_malloc(s->cluster_size); limit = bytes_covered_by_bitmap_cluster(s, bitmap); - sbc = limit >> BDRV_SECTOR_BITS; - for (i = 0, sector = 0; i < tab_size; ++i, sector += sbc) { - uint64_t count = MIN(bm_sectors - sector, sbc); + for (i = 0, offset = 0; i < tab_size; ++i, offset += limit) { + uint64_t count = MIN(bm_size - offset, limit); uint64_t entry = bitmap_table[i]; - uint64_t offset = entry & BME_TABLE_ENTRY_OFFSET_MASK; + uint64_t data_offset = entry & BME_TABLE_ENTRY_OFFSET_MASK; assert(check_table_entry(entry, s->cluster_size) == 0); - if (offset == 0) { + if (data_offset == 0) { if (entry & BME_TABLE_ENTRY_FLAG_ALL_ONES) { - bdrv_dirty_bitmap_deserialize_ones(bitmap, - sector * BDRV_SECTOR_SIZE, - count * BDRV_SECTOR_SIZE, + bdrv_dirty_bitmap_deserialize_ones(bitmap, offset, count, false); } else { /* No need to deserialize zeros because the dirty bitmap is * already cleared */ } } else { - ret = bdrv_pread(bs->file, offset, buf, s->cluster_size); + ret = bdrv_pread(bs->file, data_offset, buf, s->cluster_size); if (ret < 0) { goto finish; } - bdrv_dirty_bitmap_deserialize_part(bitmap, buf, - sector * BDRV_SECTOR_SIZE, - count * BDRV_SECTOR_SIZE, + bdrv_dirty_bitmap_deserialize_part(bitmap, buf, offset, count, false); } }