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=-6.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,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 67B3DC432C1 for ; Wed, 25 Sep 2019 00:53:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 386B421655 for ; Wed, 25 Sep 2019 00:53:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="jjPM6AOe" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2393217AbfIYAwT (ORCPT ); Tue, 24 Sep 2019 20:52:19 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:56872 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391492AbfIYAwS (ORCPT ); Tue, 24 Sep 2019 20:52:18 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.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:Resent-Date:Resent-From :Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=Msuh+GIy2CoxvHIBREeyTvGqw5Zy0zVyz1WZpxkYJLU=; b=jjPM6AOeJ3T4p2ns/p0veL1StU pLb7u0VfrTxsOUToXx7EuihWY+hieN/+gonGpGZk5xIgcajiTU07YfgpU7SniFynUrx/HPqxTaRUm Ihws+qwkWEE31PJqfwGAPKoeUfcdgeMokv7q5r/KmJqy5HTxDT/KE2kkAlrETXwgffWVYNjtL4w+z D9um7Zm3lZUQAKnd9d107iYu2CRCTMUu+67AvtxPaVePxDduc1NP3g6AR6TduLZAHkbodQyEpFP1T blk6GxeW0vnCyT2uojZJ8pBHjWpYSHujrsm2YeSnAuOPf6nFMzMMhMXlYo5d+5vUElPptm/ox1UdQ plHWZMAg==; Received: from willy by bombadil.infradead.org with local (Exim 4.92.2 #3 (Red Hat Linux)) id 1iCvXV-00076O-AM; Wed, 25 Sep 2019 00:52:17 +0000 From: Matthew Wilcox To: linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: "Matthew Wilcox (Oracle)" Subject: [PATCH 03/15] mm: Add file_offset_of_ helpers Date: Tue, 24 Sep 2019 17:52:02 -0700 Message-Id: <20190925005214.27240-4-willy@infradead.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190925005214.27240-1-willy@infradead.org> References: <20190925005214.27240-1-willy@infradead.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org From: "Matthew Wilcox (Oracle)" The page_offset function is badly named for people reading the functions which call it. The natural meaning of a function with this name would be 'offset within a page', not 'page offset in bytes within a file'. Dave Chinner suggests file_offset_of_page() as a replacement function name and I'm also adding file_offset_of_next_page() as a helper for the large page work. Also add kernel-doc for these functions so they show up in the kernel API book. page_offset() is retained as a compatibility define for now. --- drivers/net/ethernet/ibm/ibmveth.c | 2 -- include/linux/pagemap.h | 25 ++++++++++++++++++++++--- 2 files changed, 22 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/ibm/ibmveth.c b/drivers/net/ethernet/ibm/ibmveth.c index c5be4ebd8437..bf98aeaf9a45 100644 --- a/drivers/net/ethernet/ibm/ibmveth.c +++ b/drivers/net/ethernet/ibm/ibmveth.c @@ -978,8 +978,6 @@ static int ibmveth_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) return -EOPNOTSUPP; } -#define page_offset(v) ((unsigned long)(v) & ((1 << 12) - 1)) - static int ibmveth_send(struct ibmveth_adapter *adapter, union ibmveth_buf_desc *descs, unsigned long mss) { diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 750770a2c685..103205494ea0 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -428,14 +428,33 @@ static inline pgoff_t page_to_pgoff(struct page *page) return page_to_index(page); } -/* - * Return byte-offset into filesystem object for page. +/** + * file_offset_of_page - File offset of this page. + * @page: Page cache page. + * + * Context: Any context. + * Return: The offset of the first byte of this page. */ -static inline loff_t page_offset(struct page *page) +static inline loff_t file_offset_of_page(struct page *page) { return ((loff_t)page->index) << PAGE_SHIFT; } +/* Legacy; please convert callers */ +#define page_offset(page) file_offset_of_page(page) + +/** + * file_offset_of_next_page - File offset of the next page. + * @page: Page cache page. + * + * Context: Any context. + * Return: The offset of the first byte after this page. + */ +static inline loff_t file_offset_of_next_page(struct page *page) +{ + return ((loff_t)page->index + compound_nr(page)) << PAGE_SHIFT; +} + static inline loff_t page_file_offset(struct page *page) { return ((loff_t)page_index(page)) << PAGE_SHIFT; -- 2.23.0