From nobody Tue Feb 10 03:57:36 2026 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 Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1502941212083225.43543489412468; Wed, 16 Aug 2017 20:40:12 -0700 (PDT) Received: from localhost ([::1]:52552 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1diBfG-0000sE-28 for importer@patchew.org; Wed, 16 Aug 2017 23:40:10 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48371) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1diBdY-00080o-8k for qemu-devel@nongnu.org; Wed, 16 Aug 2017 23:38:25 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1diBdX-0003mr-Ai for qemu-devel@nongnu.org; Wed, 16 Aug 2017 23:38:24 -0400 Received: from mga01.intel.com ([192.55.52.88]:1602) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1diBdX-0003iP-20 for qemu-devel@nongnu.org; Wed, 16 Aug 2017 23:38:23 -0400 Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 16 Aug 2017 20:38:22 -0700 Received: from devel-ww.sh.intel.com ([10.239.48.97]) by orsmga004.jf.intel.com with ESMTP; 16 Aug 2017 20:38:18 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.41,386,1498546800"; d="scan'208";a="119892703" From: Wei Wang To: virtio-dev@lists.oasis-open.org, linux-kernel@vger.kernel.org, qemu-devel@nongnu.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, linux-mm@kvack.org, mst@redhat.com, mhocko@kernel.org, akpm@linux-foundation.org, mawilcox@microsoft.com Date: Thu, 17 Aug 2017 11:26:53 +0800 Message-Id: <1502940416-42944-3-git-send-email-wei.w.wang@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1502940416-42944-1-git-send-email-wei.w.wang@intel.com> References: <1502940416-42944-1-git-send-email-wei.w.wang@intel.com> X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 192.55.52.88 Subject: [Qemu-devel] [PATCH v14 2/5] lib/xbitmap: add xb_find_next_bit() and xb_zero() 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: aarcange@redhat.com, yang.zhang.wz@gmail.com, david@redhat.com, liliang.opensource@gmail.com, willy@infradead.org, amit.shah@redhat.com, wei.w.wang@intel.com, quan.xu@aliyun.com, cornelia.huck@de.ibm.com, pbonzini@redhat.com, mgorman@techsingularity.net 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" xb_find_next_bit() is used to find the next "1" or "0" bit in the given range. xb_zero() is used to zero the given range of bits. Signed-off-by: Wei Wang Cc: Andrew Morton Cc: Matthew Wilcox Cc: Michal Hocko Cc: Michael S. Tsirkin --- include/linux/xbitmap.h | 3 +++ lib/xbitmap.c | 39 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 42 insertions(+) diff --git a/include/linux/xbitmap.h b/include/linux/xbitmap.h index 5edbf84..739d08c 100644 --- a/include/linux/xbitmap.h +++ b/include/linux/xbitmap.h @@ -38,6 +38,9 @@ static inline void xb_init(struct xb *xb) int xb_set_bit(struct xb *xb, unsigned long bit); bool xb_test_bit(const struct xb *xb, unsigned long bit); void xb_clear_bit(struct xb *xb, unsigned long bit); +void xb_zero(struct xb *xb, unsigned long start, unsigned long end); +unsigned long xb_find_next_bit(struct xb *xb, unsigned long start, + unsigned long end, bool set); =20 /* Check if the xb tree is empty */ static inline bool xb_is_empty(const struct xb *xb) diff --git a/lib/xbitmap.c b/lib/xbitmap.c index cc766d9..2267ac2 100644 --- a/lib/xbitmap.c +++ b/lib/xbitmap.c @@ -174,3 +174,42 @@ void xb_preload(gfp_t gfp) } } EXPORT_SYMBOL(xb_preload); + +/** + * xb_zero - zero a range of bits in the xbitmap + * @xb: the xbitmap that the bits reside in + * @start: the start of the range, inclusive + * @end: the end of the range, inclusive + */ +void xb_zero(struct xb *xb, unsigned long start, unsigned long end) +{ + unsigned long i; + + for (i =3D start; i <=3D end; i++) + xb_clear_bit(xb, i); +} +EXPORT_SYMBOL(xb_zero); + +/** + * xb_find_next_bit - find next 1 or 0 in the give range of bits + * @xb: the xbitmap that the bits reside in + * @start: the start of the range, inclusive + * @end: the end of the range, inclusive + * @set: the polarity (1 or 0) of the next bit to find + * + * Return the index of the found bit in the xbitmap. If the returned index + * exceeds @end, it indicates that no such bit is found in the given range. + */ +unsigned long xb_find_next_bit(struct xb *xb, unsigned long start, + unsigned long end, bool set) +{ + unsigned long i; + + for (i =3D start; i <=3D end; i++) { + if (xb_test_bit(xb, i) =3D=3D set) + break; + } + + return i; +} +EXPORT_SYMBOL(xb_find_next_bit); --=20 2.7.4