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=-9.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 D6006C83003 for ; Wed, 29 Apr 2020 13:37:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B58DF206D6 for ; Wed, 29 Apr 2020 13:37:18 +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="mS4GHtyZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727769AbgD2NhD (ORCPT ); Wed, 29 Apr 2020 09:37:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52946 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726898AbgD2NhA (ORCPT ); Wed, 29 Apr 2020 09:37:00 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7D9ADC09B040; Wed, 29 Apr 2020 06:36:59 -0700 (PDT) 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; bh=tyoiEDA4aqW5ranAPIIS6qQtQA5yS6rXGQxRGVOBB6U=; b=mS4GHtyZBEma/U97n2kGoKvCN4 uihpLwSbMpvtN78Td9rCZsJy24ZhDi39nb0f4DuBgT7dm0A+rZKdPmG3KNa3Df0H+grThrkbtfCQb swxNDNxX9eEFySUycDJniOWL8BXGubht8trSMNEOYGJ6NfDyp66CeNwi77HBNQEDw2VhVhkOJ9uIw M9Zpfytt4C1f2LYZ6iZWwprI4JB3pzdR6IeDBLH0hk76u0MXzs9XU+J2V/ufBX1Px9T4pmygj0Vki FQetRR3rC9FXsAXYER2iPCA9qRSdryPfcTvhwCZ2RXJEFpYxRLQ8qgiCCRyGkyTM9ym79exive9ki g9/3VlqQ==; Received: from willy by bombadil.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jTmtX-0005v1-BZ; Wed, 29 Apr 2020 13:36:59 +0000 From: Matthew Wilcox To: linux-fsdevel@vger.kernel.org Cc: "Matthew Wilcox (Oracle)" , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 08/25] fs: Support THPs in zero_user_segments Date: Wed, 29 Apr 2020 06:36:40 -0700 Message-Id: <20200429133657.22632-9-willy@infradead.org> X-Mailer: git-send-email 2.21.1 In-Reply-To: <20200429133657.22632-1-willy@infradead.org> References: <20200429133657.22632-1-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)" We can only kmap() one subpage of a THP at a time, so loop over all relevant subpages, skipping ones which don't need to be zeroed. This is too large to inline when THPs are enabled and we actually need highmem, so put it in highmem.c. Signed-off-by: Matthew Wilcox (Oracle) --- include/linux/highmem.h | 15 +++++++--- mm/highmem.c | 62 +++++++++++++++++++++++++++++++++++++++-- 2 files changed, 71 insertions(+), 6 deletions(-) diff --git a/include/linux/highmem.h b/include/linux/highmem.h index ea5cdbd8c2c3..74614903619d 100644 --- a/include/linux/highmem.h +++ b/include/linux/highmem.h @@ -215,13 +215,18 @@ static inline void clear_highpage(struct page *page) kunmap_atomic(kaddr); } +#if defined(CONFIG_HIGHMEM) && defined(CONFIG_TRANSPARENT_HUGEPAGE) +void zero_user_segments(struct page *page, unsigned start1, unsigned end1, + unsigned start2, unsigned end2); +#else /* !HIGHMEM || !TRANSPARENT_HUGEPAGE */ static inline void zero_user_segments(struct page *page, - unsigned start1, unsigned end1, - unsigned start2, unsigned end2) + unsigned start1, unsigned end1, + unsigned start2, unsigned end2) { + unsigned long i; void *kaddr = kmap_atomic(page); - BUG_ON(end1 > PAGE_SIZE || end2 > PAGE_SIZE); + BUG_ON(end1 > thp_size(page) || end2 > thp_size(page)); if (end1 > start1) memset(kaddr + start1, 0, end1 - start1); @@ -230,8 +235,10 @@ static inline void zero_user_segments(struct page *page, memset(kaddr + start2, 0, end2 - start2); kunmap_atomic(kaddr); - flush_dcache_page(page); + for (i = 0; i < hpage_nr_pages(page); i++) + flush_dcache_page(page + i); } +#endif /* !HIGHMEM || !TRANSPARENT_HUGEPAGE */ static inline void zero_user_segment(struct page *page, unsigned start, unsigned end) diff --git a/mm/highmem.c b/mm/highmem.c index 64d8dea47dd1..3a85c66ef532 100644 --- a/mm/highmem.c +++ b/mm/highmem.c @@ -367,9 +367,67 @@ void kunmap_high(struct page *page) if (need_wakeup) wake_up(pkmap_map_wait); } - EXPORT_SYMBOL(kunmap_high); -#endif + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +void zero_user_segments(struct page *page, unsigned start1, unsigned end1, + unsigned start2, unsigned end2) +{ + unsigned int i; + + BUG_ON(end1 > thp_size(page) || end2 > thp_size(page)); + + for (i = 0; i < hpage_nr_pages(page); i++) { + void *kaddr; + unsigned this_end; + + if (end1 == 0 && start2 >= PAGE_SIZE) { + start2 -= PAGE_SIZE; + end2 -= PAGE_SIZE; + continue; + } + + if (start1 >= PAGE_SIZE) { + start1 -= PAGE_SIZE; + end1 -= PAGE_SIZE; + if (start2) { + start2 -= PAGE_SIZE; + end2 -= PAGE_SIZE; + } + continue; + } + + kaddr = kmap_atomic(page + i); + + this_end = min_t(unsigned, end1, PAGE_SIZE); + if (end1 > start1) + memset(kaddr + start1, 0, this_end - start1); + end1 -= this_end; + start1 = 0; + + if (start2 >= PAGE_SIZE) { + start2 -= PAGE_SIZE; + end2 -= PAGE_SIZE; + } else { + this_end = min_t(unsigned, end2, PAGE_SIZE); + if (end2 > start2) + memset(kaddr + start2, 0, this_end - start2); + end2 -= this_end; + start2 = 0; + } + + kunmap_atomic(kaddr); + flush_dcache_page(page + i); + + if (!end1 && !end2) + break; + } + + BUG_ON((start1 | start2 | end1 | end2) != 0); +} +EXPORT_SYMBOL(zero_user_segments); +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ +#endif /* CONFIG_HIGHMEM */ #if defined(HASHED_PAGE_VIRTUAL) -- 2.26.2