From nobody Wed Dec 17 21:59:25 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 (208.118.235.17 [208.118.235.17]) by mx.zohomail.com with SMTPS id 1529342501131977.9484995833327; Mon, 18 Jun 2018 10:21:41 -0700 (PDT) Received: from localhost ([::1]:36160 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fUxqP-0006R7-8L for importer@patchew.org; Mon, 18 Jun 2018 13:21:33 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52355) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fUxHi-0005Ga-VI for qemu-devel@nongnu.org; Mon, 18 Jun 2018 12:45:44 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fUxHh-0006Vv-Pt for qemu-devel@nongnu.org; Mon, 18 Jun 2018 12:45:43 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:41704 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 1fUxHd-0006RW-9K; Mon, 18 Jun 2018 12:45:37 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id CD6AA81663D6; Mon, 18 Jun 2018 16:45:36 +0000 (UTC) Received: from localhost.localdomain.com (ovpn-117-120.ams2.redhat.com [10.36.117.120]) by smtp.corp.redhat.com (Postfix) with ESMTP id 26E552026D5B; Mon, 18 Jun 2018 16:45:36 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Date: Mon, 18 Jun 2018 18:44:59 +0200 Message-Id: <20180618164504.24488-31-kwolf@redhat.com> In-Reply-To: <20180618164504.24488-1-kwolf@redhat.com> References: <20180618164504.24488-1-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.8]); Mon, 18 Jun 2018 16:45:36 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.8]); Mon, 18 Jun 2018 16:45:36 +0000 (UTC) for IP:'10.11.54.4' DOMAIN:'int-mx04.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'kwolf@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] [PULL 30/35] 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: kwolf@redhat.com, qemu-devel@nongnu.org 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" From: Max Reitz This new function allows to look for a consecutively dirty area in a dirty bitmap. Signed-off-by: Max Reitz Reviewed-by: Fam Zheng Reviewed-by: John Snow Message-id: 20180613181823.13618-10-mreitz@redhat.com Signed-off-by: Max Reitz --- 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 02e0cbabd2..288dc6adb6 100644 --- a/include/block/dirty-bitmap.h +++ b/include/block/dirty-bitmap.h @@ -82,6 +82,8 @@ 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 cedb971765..db1782ec1f 100644 --- a/block/dirty-bitmap.c +++ b/block/dirty-bitmap.c @@ -522,6 +522,61 @@ 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 2.13.6