From patchwork Fri Oct 12 11:49:13 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 983008 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 42WmP52vgQz9s3Z for ; Fri, 12 Oct 2018 22:50:33 +1100 (AEDT) Received: from localhost ([::1]:39631 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gAvxf-00031c-0x for incoming@patchwork.ozlabs.org; Fri, 12 Oct 2018 07:50:31 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36331) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gAvwu-0002zZ-SY for qemu-devel@nongnu.org; Fri, 12 Oct 2018 07:49:45 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gAvwr-0000fv-Ds for qemu-devel@nongnu.org; Fri, 12 Oct 2018 07:49:43 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45596) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gAvwp-0000Io-3Q for qemu-devel@nongnu.org; Fri, 12 Oct 2018 07:49:39 -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 7915F7F3F7; Fri, 12 Oct 2018 11:49:35 +0000 (UTC) Received: from t460s.redhat.com (ovpn-116-36.ams2.redhat.com [10.36.116.36]) by smtp.corp.redhat.com (Postfix) with ESMTP id 671986F10A; Fri, 12 Oct 2018 11:49:33 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Date: Fri, 12 Oct 2018 13:49:13 +0200 Message-Id: <20181012114916.23532-5-david@redhat.com> In-Reply-To: <20181012114916.23532-1-david@redhat.com> References: <20181012114916.23532-1-david@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]); Fri, 12 Oct 2018 11:49:35 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v2 4/7] range: add some more functions 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: Eduardo Habkost , "Michael S . Tsirkin" , David Hildenbrand , Michael Roth , Markus Armbruster , Igor Mammedov , "Dr . David Alan Gilbert" , David Gibson Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" Add some more functions that will be used in memory-device context. range_init(): Init using lower bound and size, check for validity range_init_nofail(): Init using lower bound and size, validity asserted range_size(): Extract the size of a range range_overlaps_range(): Check for overlaps of two ranges range_contains_range(): Check if one range is contained in the other Signed-off-by: David Hildenbrand --- include/qemu/range.h | 62 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) diff --git a/include/qemu/range.h b/include/qemu/range.h index 7e75f4e655..ba606c6bc0 100644 --- a/include/qemu/range.h +++ b/include/qemu/range.h @@ -112,6 +112,68 @@ static inline uint64_t range_upb(Range *range) return range->upb; } +/* + * Initialize @range to span the interval [@lob,@lob + @size - 1]. + * @size may be 0. If the range would overflow, returns -ERANGE, otherwise + * 0. + */ +static inline int QEMU_WARN_UNUSED_RESULT range_init(Range *range, uint64_t lob, + uint64_t size) +{ + if (lob + size < lob) { + return -ERANGE; + } + range->lob = lob; + range->upb = lob + size - 1; + range_invariant(range); + return 0; +} + +/* + * Initialize @range to span the interval [@lob,@lob + @size - 1]. + * @size may be 0. Range must not overflow. + */ +static inline void range_init_nofail(Range *range, uint64_t lob, uint64_t size) +{ + range->lob = lob; + range->upb = lob + size - 1; + range_invariant(range); +} + +/* + * Get the size of @range. + */ +static inline uint64_t range_size(const Range *range) +{ + return range->upb - range->lob + 1; +} + +/* + * Check if @range1 overlaps with @range2. If one of the ranges is empty, + * the result is always "false". + */ +static inline bool range_overlaps_range(const Range *range1, + const Range *range2) +{ + if (range_is_empty(range1) || range_is_empty(range2)) { + return false; + } + return !(range2->upb < range1->lob || range1->upb < range2->lob); +} + +/* + * Check if @range1 contains @range2. If one of the ranges is empty, + * the result is always "false". + */ +static inline bool range_contains_range(const Range *range1, + const Range *range2) +{ + if (range_is_empty(range1) || range_is_empty(range2)) { + return false; + } + return range1->lob <= range2->lob && range1->upb >= range2->upb; +} + /* * Extend @range to the smallest interval that includes @extend_by, too. */