From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 19D41C48BD4 for ; Tue, 25 Jun 2019 07:53:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E500420665 for ; Tue, 25 Jun 2019 07:53:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730097AbfFYHxO (ORCPT ); Tue, 25 Jun 2019 03:53:14 -0400 Received: from smtp.nue.novell.com ([195.135.221.5]:51793 "EHLO smtp.nue.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728310AbfFYHxK (ORCPT ); Tue, 25 Jun 2019 03:53:10 -0400 Received: from emea4-mta.ukb.novell.com ([10.120.13.87]) by smtp.nue.novell.com with ESMTP (TLS encrypted); Tue, 25 Jun 2019 09:53:09 +0200 Received: from suse.de (nwb-a10-snat.microfocus.com [10.120.13.201]) by emea4-mta.ukb.novell.com with ESMTP (NOT encrypted); Tue, 25 Jun 2019 08:52:34 +0100 From: Oscar Salvador To: akpm@linux-foundation.org Cc: mhocko@suse.com, dan.j.williams@intel.com, pasha.tatashin@soleen.com, Jonathan.Cameron@huawei.com, david@redhat.com, anshuman.khandual@arm.com, vbabka@suse.cz, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Oscar Salvador Subject: [PATCH v2 3/5] mm,memory_hotplug: Introduce Vmemmap page helpers Date: Tue, 25 Jun 2019 09:52:25 +0200 Message-Id: <20190625075227.15193-4-osalvador@suse.de> X-Mailer: git-send-email 2.13.7 In-Reply-To: <20190625075227.15193-1-osalvador@suse.de> References: <20190625075227.15193-1-osalvador@suse.de> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Introduce a set of functions for Vmemmap pages. Set of functions: - {Set,Clear,Check} Vmemmap flag - Given a vmemmap page, get its vmemmap-head - Get #nr of vmemmap pages taking into account the current position of the page These functions will be used for the code handling Vmemmap pages. Signed-off-by: Oscar Salvador --- include/linux/page-flags.h | 34 ++++++++++++++++++++++++++++++++++ mm/util.c | 2 ++ 2 files changed, 36 insertions(+) diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index b848517da64c..a8b9b57162b3 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -466,6 +466,40 @@ static __always_inline int __PageMovable(struct page *page) PAGE_MAPPING_MOVABLE; } +#define VMEMMAP_PAGE (~PAGE_MAPPING_FLAGS) +static __always_inline int PageVmemmap(struct page *page) +{ + return PageReserved(page) && (unsigned long)page->mapping == VMEMMAP_PAGE; +} + +static __always_inline int __PageVmemmap(struct page *page) +{ + return (unsigned long)page->mapping == VMEMMAP_PAGE; +} + +static __always_inline void __ClearPageVmemmap(struct page *page) +{ + __ClearPageReserved(page); + page->mapping = NULL; +} + +static __always_inline void __SetPageVmemmap(struct page *page) +{ + __SetPageReserved(page); + page->mapping = (void *)VMEMMAP_PAGE; +} + +static __always_inline struct page *vmemmap_get_head(struct page *page) +{ + return (struct page *)page->freelist; +} + +static __always_inline unsigned long get_nr_vmemmap_pages(struct page *page) +{ + struct page *head = vmemmap_get_head(page); + return head->private - (page - head); +} + #ifdef CONFIG_KSM /* * A KSM page is one of those write-protected "shared pages" or "merged pages" diff --git a/mm/util.c b/mm/util.c index 021648a8a3a3..5e20563cdef6 100644 --- a/mm/util.c +++ b/mm/util.c @@ -607,6 +607,8 @@ struct address_space *page_mapping(struct page *page) mapping = page->mapping; if ((unsigned long)mapping & PAGE_MAPPING_ANON) return NULL; + if ((unsigned long)mapping == VMEMMAP_PAGE) + return NULL; return (void *)((unsigned long)mapping & ~PAGE_MAPPING_FLAGS); } -- 2.12.3