From patchwork Mon Aug 8 06:35:30 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Liang Z" X-Patchwork-Id: 656555 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3s77MK5THyz9sR9 for ; Mon, 8 Aug 2016 16:50:05 +1000 (AEST) Received: from localhost ([::1]:55243 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bWeNv-0007iM-FP for incoming@patchwork.ozlabs.org; Mon, 08 Aug 2016 02:50:03 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37517) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bWeHT-0001Zf-CA for qemu-devel@nongnu.org; Mon, 08 Aug 2016 02:43:24 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bWeHO-0007yc-EF for qemu-devel@nongnu.org; Mon, 08 Aug 2016 02:43:22 -0400 Received: from mga03.intel.com ([134.134.136.65]:37884) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bWeHO-0007yQ-7l for qemu-devel@nongnu.org; Mon, 08 Aug 2016 02:43:18 -0400 Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga103.jf.intel.com with ESMTP; 07 Aug 2016 23:43:17 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos; i="5.28,488,1464678000"; d="scan'208"; a="1031549356" Received: from ll.sh.intel.com (HELO localhost) ([10.239.13.123]) by orsmga002.jf.intel.com with ESMTP; 07 Aug 2016 23:43:14 -0700 From: Liang Li To: linux-kernel@vger.kernel.org Date: Mon, 8 Aug 2016 14:35:30 +0800 Message-Id: <1470638134-24149-4-git-send-email-liang.z.li@intel.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1470638134-24149-1-git-send-email-liang.z.li@intel.com> References: <1470638134-24149-1-git-send-email-liang.z.li@intel.com> X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 134.134.136.65 Subject: [Qemu-devel] [PATCH v3 kernel 3/7] mm: add a function to get the max pfn 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: virtio-dev@lists.oasis-open.org, kvm@vger.kernel.org, quintela@redhat.com, Amit Shah , Liang Li , dave.hansen@intel.com, qemu-devel@nongnu.org, virtualization@lists.linux-foundation.org, linux-mm@kvack.org, "Michael S. Tsirkin" , Cornelia Huck , Paolo Bonzini , Andrew Morton , Mel Gorman , dgilbert@redhat.com Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" Expose the function to get the max pfn, so it can be used in the virtio-balloon device driver. Simply include the 'linux/bootmem.h' is not enough, if the device driver is built to a module, directly refer the max_pfn lead to build failed. Signed-off-by: Liang Li Cc: Andrew Morton Cc: Mel Gorman Cc: Michael S. Tsirkin Cc: Paolo Bonzini Cc: Cornelia Huck Cc: Amit Shah Cc: Dave Hansen --- include/linux/mm.h | 1 + mm/page_alloc.c | 10 ++++++++++ 2 files changed, 11 insertions(+) diff --git a/include/linux/mm.h b/include/linux/mm.h index 08ed53e..5873057 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1788,6 +1788,7 @@ extern void free_area_init(unsigned long * zones_size); extern void free_area_init_node(int nid, unsigned long * zones_size, unsigned long zone_start_pfn, unsigned long *zholes_size); extern void free_initmem(void); +extern unsigned long get_max_pfn(void); /* * Free reserved pages within range [PAGE_ALIGN(start), end & PAGE_MASK) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index fb975ce..3373704 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -4391,6 +4391,16 @@ void show_free_areas(unsigned int filter) show_swap_cache_info(); } +/* + * The max_pfn can change because of memory hot plug, so it's only good + * as a hint. e.g. for sizing data structures. + */ +unsigned long get_max_pfn(void) +{ + return max_pfn; +} +EXPORT_SYMBOL(get_max_pfn); + static void zoneref_set_zone(struct zone *zone, struct zoneref *zoneref) { zoneref->zone = zone;