From nobody Fri Oct 24 22:17:01 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1519841806711941.6558639958254; Wed, 28 Feb 2018 10:16:46 -0800 (PST) Received: from localhost ([::1]:46019 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1er6HV-0005Jl-Gr for importer@patchew.org; Wed, 28 Feb 2018 13:16:45 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41877) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1er67I-0004lx-4d for qemu-devel@nongnu.org; Wed, 28 Feb 2018 13:06:13 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1er67D-0004cQ-Vs for qemu-devel@nongnu.org; Wed, 28 Feb 2018 13:06:12 -0500 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:42282 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1er67B-0004Xq-FA; Wed, 28 Feb 2018 13:06:05 -0500 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 13F474075166; Wed, 28 Feb 2018 18:06:05 +0000 (UTC) Received: from localhost (unknown [10.40.205.159]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 93B0B9C051; Wed, 28 Feb 2018 18:05:58 +0000 (UTC) From: Max Reitz To: qemu-block@nongnu.org Date: Wed, 28 Feb 2018 19:05:03 +0100 Message-Id: <20180228180507.3964-13-mreitz@redhat.com> In-Reply-To: <20180228180507.3964-1-mreitz@redhat.com> References: <20180228180507.3964-1-mreitz@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Wed, 28 Feb 2018 18:06:05 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.7]); Wed, 28 Feb 2018 18:06:05 +0000 (UTC) for IP:'10.11.54.5' DOMAIN:'int-mx05.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'mreitz@redhat.com' RCPT:'' X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 66.187.233.73 Subject: [Qemu-devel] [PATCH v3 12/16] block/dirty-bitmap: Add bdrv_dirty_iter_next_area 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-devel@nongnu.org, Max Reitz , Stefan Hajnoczi , John Snow Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" This new function allows to look for a consecutively dirty area in a dirty bitmap. Signed-off-by: Max Reitz Reviewed-by: John Snow --- include/block/dirty-bitmap.h | 2 ++ block/dirty-bitmap.c | 55 ++++++++++++++++++++++++++++++++++++++++= ++++ 2 files changed, 57 insertions(+) diff --git a/include/block/dirty-bitmap.h b/include/block/dirty-bitmap.h index e3f4bbf51d..8c8f63e722 100644 --- a/include/block/dirty-bitmap.h +++ b/include/block/dirty-bitmap.h @@ -79,6 +79,8 @@ void bdrv_set_dirty_bitmap_locked(BdrvDirtyBitmap *bitmap, void bdrv_reset_dirty_bitmap_locked(BdrvDirtyBitmap *bitmap, int64_t offset, int64_t bytes); int64_t bdrv_dirty_iter_next(BdrvDirtyBitmapIter *iter); +bool bdrv_dirty_iter_next_area(BdrvDirtyBitmapIter *iter, uint64_t max_off= set, + uint64_t *offset, int *bytes); void bdrv_set_dirty_iter(BdrvDirtyBitmapIter *hbi, int64_t offset); int64_t bdrv_get_dirty_count(BdrvDirtyBitmap *bitmap); int64_t bdrv_get_meta_dirty_count(BdrvDirtyBitmap *bitmap); diff --git a/block/dirty-bitmap.c b/block/dirty-bitmap.c index d8e999226e..5d6b8dba89 100644 --- a/block/dirty-bitmap.c +++ b/block/dirty-bitmap.c @@ -496,6 +496,61 @@ int64_t bdrv_dirty_iter_next(BdrvDirtyBitmapIter *iter) return hbitmap_iter_next(&iter->hbi, true); } =20 +/** + * Return the next consecutively dirty area in the dirty bitmap + * belonging to the given iterator @iter. + * + * @max_offset: Maximum value that may be returned for + * *offset + *bytes + * @offset: Will contain the start offset of the next dirty area + * @bytes: Will contain the length of the next dirty area + * + * Returns: True if a dirty area could be found before max_offset + * (which means that *offset and *bytes then contain valid + * values), false otherwise. + * + * Note that @iter is never advanced if false is returned. If an area + * is found (which means that true is returned), it will be advanced + * past that area. + */ +bool bdrv_dirty_iter_next_area(BdrvDirtyBitmapIter *iter, uint64_t max_off= set, + uint64_t *offset, int *bytes) +{ + uint32_t granularity =3D bdrv_dirty_bitmap_granularity(iter->bitmap); + uint64_t gran_max_offset; + int64_t ret; + int size; + + if (max_offset =3D=3D iter->bitmap->size) { + /* If max_offset points to the image end, round it up by the + * bitmap granularity */ + gran_max_offset =3D ROUND_UP(max_offset, granularity); + } else { + gran_max_offset =3D max_offset; + } + + ret =3D hbitmap_iter_next(&iter->hbi, false); + if (ret < 0 || ret + granularity > gran_max_offset) { + return false; + } + + *offset =3D ret; + size =3D 0; + + assert(granularity <=3D INT_MAX); + + do { + /* Advance iterator */ + ret =3D hbitmap_iter_next(&iter->hbi, true); + size +=3D granularity; + } while (ret + granularity <=3D gran_max_offset && + hbitmap_iter_next(&iter->hbi, false) =3D=3D ret + granularity= && + size <=3D INT_MAX - granularity); + + *bytes =3D MIN(size, max_offset - *offset); + return true; +} + /* Called within bdrv_dirty_bitmap_lock..unlock */ void bdrv_set_dirty_bitmap_locked(BdrvDirtyBitmap *bitmap, int64_t offset, int64_t bytes) --=20 2.14.3