From patchwork Wed Mar 31 18:47:15 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthew Wilcox X-Patchwork-Id: 12175987 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=-16.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 831DFC43460 for ; Wed, 31 Mar 2021 18:53:33 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 271E461006 for ; Wed, 31 Mar 2021 18:53:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 271E461006 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id BBF4D6B00A4; Wed, 31 Mar 2021 14:53:32 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B6E076B00A5; Wed, 31 Mar 2021 14:53:32 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A5EDB6B00A6; Wed, 31 Mar 2021 14:53:32 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0024.hostedemail.com [216.40.44.24]) by kanga.kvack.org (Postfix) with ESMTP id 88F3A6B00A4 for ; Wed, 31 Mar 2021 14:53:32 -0400 (EDT) Received: from smtpin39.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 43E0B8249980 for ; Wed, 31 Mar 2021 18:53:32 +0000 (UTC) X-FDA: 77981067864.39.DF86EBB Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf18.hostedemail.com (Postfix) with ESMTP id EB16D2000250 for ; Wed, 31 Mar 2021 18:53:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=nVyXR6HRjLgu3KkaVohlQVN86exh8AV6iRsShfPIk6Y=; b=uiGvyaj+PWljHx/9rLlLwe7+xF vG/ae1A+9GMCVFrNucOB4Jg872lTaABHUfEC+PYyKVmCuhFbA/NlaMVnqRXlFirYmcPrpGq7VYube Yw5ccBPGnBHb+P6KYNvy0GvWx1nvNqcZifomeSwngNKuMbTN2Z5/5EdJ8zA2mh3sERFzAIGTImOsz U6zif4YDUChrW1NxPxZROPASaDYk20a8kFy4EFNXZEhZtUwdTJ8U4NQWHbi/AVLtJidE5IpA/T6ex RvT7GZLbZrBtlEUHEoS82+ZaKD+GsJYwajfgpf3xOJMbAc/ZJr2OtxfJYUCpd0KiDi97W0bgW1Rm7 q0SPdpTA==; Received: from willy by casper.infradead.org with local (Exim 4.94 #2 (Red Hat Linux)) id 1lRfx7-004zYl-H7; Wed, 31 Mar 2021 18:52:44 +0000 From: "Matthew Wilcox (Oracle)" To: linux-mm@kvack.org Cc: "Matthew Wilcox (Oracle)" , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-cachefs@redhat.com, linux-afs@lists.infradead.org Subject: [PATCH v6 14/27] mm: Add folio_mapcount Date: Wed, 31 Mar 2021 19:47:15 +0100 Message-Id: <20210331184728.1188084-15-willy@infradead.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210331184728.1188084-1-willy@infradead.org> References: <20210331184728.1188084-1-willy@infradead.org> MIME-Version: 1.0 X-Rspamd-Queue-Id: EB16D2000250 X-Stat-Signature: qaq3sregjzcf49aunwsmwmbufp79f9ni X-Rspamd-Server: rspam02 Received-SPF: none (infradead.org>: No applicable sender policy available) receiver=imf18; identity=mailfrom; envelope-from=""; helo=casper.infradead.org; client-ip=90.155.50.34 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1617216810-139272 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: This is the folio equivalent of page_mapcount(). Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Christoph Hellwig --- include/linux/mm.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/include/linux/mm.h b/include/linux/mm.h index a4f2818aeb1d..fc15a256e686 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -869,6 +869,22 @@ static inline int page_mapcount(struct page *page) return atomic_read(&page->_mapcount) + 1; } +/** + * folio_mapcount - The number of mappings of this folio. + * @folio: The folio. + * + * The result includes the number of times any of the pages in the + * folio are mapped to userspace. + * + * Return: The number of page table entries which refer to this folio. + */ +static inline int folio_mapcount(struct folio *folio) +{ + if (unlikely(FolioMulti(folio))) + return __page_mapcount(&folio->page); + return atomic_read(&folio->_mapcount) + 1; +} + #ifdef CONFIG_TRANSPARENT_HUGEPAGE int total_mapcount(struct page *page); int page_trans_huge_mapcount(struct page *page, int *total_mapcount);