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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 CAEDEC433E0 for ; Wed, 24 Feb 2021 20:04:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8DA5B64F2D for ; Wed, 24 Feb 2021 20:04:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235287AbhBXUE0 (ORCPT ); Wed, 24 Feb 2021 15:04:26 -0500 Received: from mail.kernel.org ([198.145.29.99]:55470 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235216AbhBXUDH (ORCPT ); Wed, 24 Feb 2021 15:03:07 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 5049964F14; Wed, 24 Feb 2021 20:02:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1614196949; bh=cl43UZV3YQvoxhUQicgJiuTx+VGzf0FHHHIdTHt3ITE=; h=Date:From:To:Subject:In-Reply-To:From; b=JXwasE6KUBHAK8feAsAOgc2EI3qkrb/h57+3VOg7yzii4SvHb2qJjH9tTLJEMCxAy uvR3Y7GNudPOD6ecREabcZSviG4xPVEY9XOAB3InzPifw/WF4JNjG+hWN9b06fF0jf Kvm8b9LKQsX6TDM9GbvIYSiKtphOUdJvG+sr+6Ak= Date: Wed, 24 Feb 2021 12:02:28 -0800 From: Andrew Morton To: akpm@linux-foundation.org, hch@lst.de, kent.overstreet@gmail.com, linmiaohe@huawei.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org, willy@infradead.org Subject: [patch 042/173] mm/filemap: add filemap_range_uptodate Message-ID: <20210224200228.uUlzvUdtO%akpm@linux-foundation.org> In-Reply-To: <20210224115824.1e289a6895087f10c41dd8d6@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: "Matthew Wilcox (Oracle)" Subject: mm/filemap: add filemap_range_uptodate Move the complicated condition and the calculations out of filemap_update_page() into its own function. [willy@infradead.org: unlock page before dropping its refcount] Link: https://lkml.kernel.org/r/20210201125229.GO308988@casper.infradead.org Link: https://lkml.kernel.org/r/20210122160140.223228-14-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Kent Overstreet Reviewed-by: Christoph Hellwig Cc: Miaohe Lin Signed-off-by: Andrew Morton --- mm/filemap.c | 65 +++++++++++++++++++++++++++++-------------------- 1 file changed, 39 insertions(+), 26 deletions(-) --- a/mm/filemap.c~mm-filemap-add-filemap_range_uptodate +++ a/mm/filemap.c @@ -2233,11 +2233,36 @@ static int filemap_read_page(struct file return error; } +static bool filemap_range_uptodate(struct address_space *mapping, + loff_t pos, struct iov_iter *iter, struct page *page) +{ + int count; + + if (PageUptodate(page)) + return true; + /* pipes can't handle partially uptodate pages */ + if (iov_iter_is_pipe(iter)) + return false; + if (!mapping->a_ops->is_partially_uptodate) + return false; + if (mapping->host->i_blkbits >= (PAGE_SHIFT + thp_order(page))) + return false; + + count = iter->count; + if (page_offset(page) > pos) { + count -= page_offset(page) - pos; + pos = 0; + } else { + pos -= page_offset(page); + } + + return mapping->a_ops->is_partially_uptodate(page, pos, count); +} + static int filemap_update_page(struct kiocb *iocb, struct address_space *mapping, struct iov_iter *iter, - struct page *page, loff_t pos, loff_t count) + struct page *page) { - struct inode *inode = mapping->host; int error; if (!trylock_page(page)) { @@ -2254,26 +2279,15 @@ static int filemap_update_page(struct ki if (!page->mapping) goto truncated; - if (PageUptodate(page)) - goto uptodate; - if (inode->i_blkbits == PAGE_SHIFT || - !mapping->a_ops->is_partially_uptodate) - goto readpage; - /* pipes can't handle partially uptodate pages */ - if (unlikely(iov_iter_is_pipe(iter))) - goto readpage; - if (!mapping->a_ops->is_partially_uptodate(page, - pos & (thp_size(page) - 1), count)) - goto readpage; -uptodate: - unlock_page(page); - return 0; -readpage: - if (iocb->ki_flags & (IOCB_NOIO | IOCB_NOWAIT | IOCB_WAITQ)) { - unlock_page(page); - return -EAGAIN; - } + error = 0; + if (filemap_range_uptodate(mapping, iocb->ki_pos, iter, page)) + goto unlock; + + error = -EAGAIN; + if (iocb->ki_flags & (IOCB_NOIO | IOCB_NOWAIT | IOCB_WAITQ)) + goto unlock; + error = filemap_read_page(iocb->ki_filp, mapping, page); if (error == AOP_TRUNCATED_PAGE) put_page(page); @@ -2282,6 +2296,9 @@ truncated: unlock_page(page); put_page(page); return AOP_TRUNCATED_PAGE; +unlock: + unlock_page(page); + return error; } static int filemap_create_page(struct file *file, @@ -2351,9 +2368,6 @@ got_pages: { struct page *page = pvec->pages[pvec->nr - 1]; pgoff_t pg_index = page->index; - loff_t pg_pos = max(iocb->ki_pos, - (loff_t) pg_index << PAGE_SHIFT); - loff_t pg_count = iocb->ki_pos + iter->count - pg_pos; if (PageReadahead(page)) { if (iocb->ki_flags & IOCB_NOIO) { @@ -2370,8 +2384,7 @@ got_pages: if ((iocb->ki_flags & IOCB_WAITQ) && pagevec_count(pvec) > 1) iocb->ki_flags |= IOCB_NOWAIT; - err = filemap_update_page(iocb, mapping, iter, page, - pg_pos, pg_count); + err = filemap_update_page(iocb, mapping, iter, page); if (err) { if (err < 0) put_page(page); _