From patchwork Fri Jul 3 15:37:01 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Catalin Marinas X-Patchwork-Id: 11642115 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 6AB9392A for ; Fri, 3 Jul 2020 15:40:50 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3E21D20899 for ; Fri, 3 Jul 2020 15:40:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="hn2l7Ptw" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3E21D20899 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=PCnkLuaYpkl98fz+eyGNLrCPFgD9KfvotXw4BTieLNk=; b=hn2l7Ptws1WWC96+0T6VfXv1s JXPgcdy2KLwjSMbDZKK66bE2O0rIouUUpmBERXur+w3QhTgPyEzcNanb7tpYXfalWZw/HOOQ7IC1Y NwrjyS7verUXWEKnNChwcOsKrUBCPC0jXO22olafyNLFthl4EiiOME466hBdClSFKjBJw2WEOn9hp G47DhsN2y5WvFJUDZmbP2/AHCVju/hHZFAULKoqMvyaIWuF0ihQfxgF0fJA63mneZ6PNaAFujksOZ kN8VHxjFLhv000w7ngg38fxkgRENpUT8QZORVdQqR+yUIsLiSp2RaB7HVP8iIXtMRQkRTZcuDZXpm JgCscgxtQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jrNm2-0001jC-TB; Fri, 03 Jul 2020 15:38:46 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jrNl3-0001DA-An for linux-arm-kernel@lists.infradead.org; Fri, 03 Jul 2020 15:37:47 +0000 Received: from localhost.localdomain (unknown [95.146.230.158]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A53FA21534; Fri, 3 Jul 2020 15:37:42 +0000 (UTC) From: Catalin Marinas To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v6 09/26] arm64: mte: Tags-aware copy_{user_, }highpage() implementations Date: Fri, 3 Jul 2020 16:37:01 +0100 Message-Id: <20200703153718.16973-10-catalin.marinas@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200703153718.16973-1-catalin.marinas@arm.com> References: <20200703153718.16973-1-catalin.marinas@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200703_113745_603955_A5B607D1 X-CRM114-Status: GOOD ( 17.59 ) X-Spam-Score: -5.0 (-----) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (-5.0 points) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at https://www.dnswl.org/, high trust [198.145.29.99 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 HEADER_FROM_DIFFERENT_DOMAINS From and EnvelopeFrom 2nd level mail domains are different 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch@vger.kernel.org, Szabolcs Nagy , Andrey Konovalov , Kevin Brodsky , Peter Collingbourne , linux-mm@kvack.org, Andrew Morton , Vincenzo Frascino , Will Deacon , Dave P Martin Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org From: Vincenzo Frascino When the Memory Tagging Extension is enabled, the tags need to be preserved across page copy (e.g. for copy-on-write, page migration). Introduce MTE-aware copy_{user_,}highpage() functions to copy tags to the destination if the source page has the PG_mte_tagged flag set. copy_user_page() does not need to handle tag copying since, with this patch, it is only called by the DAX code where there is no source page structure (and no source tags). Signed-off-by: Vincenzo Frascino Co-developed-by: Catalin Marinas Signed-off-by: Catalin Marinas Cc: Will Deacon --- Notes: v5: - Handle tags in copy_highpage() (previously only copy_user_highpage()). - Ignore tags in copy_user_page() since it is only called directly by the DAX code where there is no source page structure. - Fix missing ret in mte_copy_page_tags(). v4: - Moved the tag copying to a separate function in mte.S and only called if the source page has the PG_mte_tagged flag set. arch/arm64/include/asm/mte.h | 4 ++++ arch/arm64/include/asm/page.h | 14 +++++++++++--- arch/arm64/lib/mte.S | 19 +++++++++++++++++++ arch/arm64/mm/copypage.c | 25 +++++++++++++++++++++---- 4 files changed, 55 insertions(+), 7 deletions(-) diff --git a/arch/arm64/include/asm/mte.h b/arch/arm64/include/asm/mte.h index 1716b3d02489..b2577eee62c2 100644 --- a/arch/arm64/include/asm/mte.h +++ b/arch/arm64/include/asm/mte.h @@ -19,6 +19,7 @@ void mte_clear_page_tags(void *addr); #define PG_mte_tagged PG_arch_2 void mte_sync_tags(pte_t *ptep, pte_t pte); +void mte_copy_page_tags(void *kto, const void *kfrom); void flush_mte_state(void); #else @@ -29,6 +30,9 @@ void flush_mte_state(void); static inline void mte_sync_tags(pte_t *ptep, pte_t pte) { } +static inline void mte_copy_page_tags(void *kto, const void *kfrom) +{ +} static inline void flush_mte_state(void) { } diff --git a/arch/arm64/include/asm/page.h b/arch/arm64/include/asm/page.h index c01b52add377..11734ce29702 100644 --- a/arch/arm64/include/asm/page.h +++ b/arch/arm64/include/asm/page.h @@ -15,18 +15,26 @@ #include /* for READ_IMPLIES_EXEC */ #include +struct page; +struct vm_area_struct; + extern void __cpu_clear_user_page(void *p, unsigned long user); -extern void __cpu_copy_user_page(void *to, const void *from, - unsigned long user); extern void copy_page(void *to, const void *from); extern void clear_page(void *to); +void copy_user_highpage(struct page *to, struct page *from, + unsigned long vaddr, struct vm_area_struct *vma); +#define __HAVE_ARCH_COPY_USER_HIGHPAGE + +void copy_highpage(struct page *to, struct page *from); +#define __HAVE_ARCH_COPY_HIGHPAGE + #define __alloc_zeroed_user_highpage(movableflags, vma, vaddr) \ alloc_page_vma(GFP_HIGHUSER | __GFP_ZERO | movableflags, vma, vaddr) #define __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE #define clear_user_page(addr,vaddr,pg) __cpu_clear_user_page(addr, vaddr) -#define copy_user_page(to,from,vaddr,pg) __cpu_copy_user_page(to, from, vaddr) +#define copy_user_page(to, from, vaddr, pg) copy_page(to, from) typedef struct page *pgtable_t; diff --git a/arch/arm64/lib/mte.S b/arch/arm64/lib/mte.S index a36705640086..3c3d0edbbca3 100644 --- a/arch/arm64/lib/mte.S +++ b/arch/arm64/lib/mte.S @@ -5,6 +5,7 @@ #include #include +#include #include .arch armv8.5-a+memtag @@ -32,3 +33,21 @@ SYM_FUNC_START(mte_clear_page_tags) b.ne 1b ret SYM_FUNC_END(mte_clear_page_tags) + +/* + * Copy the tags from the source page to the destination one + * x0 - address of the destination page + * x1 - address of the source page + */ +SYM_FUNC_START(mte_copy_page_tags) + mov x2, x0 + mov x3, x1 + multitag_transfer_size x5, x6 +1: ldgm x4, [x3] + stgm x4, [x2] + add x2, x2, x5 + add x3, x3, x5 + tst x2, #(PAGE_SIZE - 1) + b.ne 1b + ret +SYM_FUNC_END(mte_copy_page_tags) diff --git a/arch/arm64/mm/copypage.c b/arch/arm64/mm/copypage.c index 2ee7b73433a5..4a2233fa674e 100644 --- a/arch/arm64/mm/copypage.c +++ b/arch/arm64/mm/copypage.c @@ -6,18 +6,35 @@ * Copyright (C) 2012 ARM Ltd. */ +#include #include #include #include +#include +#include -void __cpu_copy_user_page(void *kto, const void *kfrom, unsigned long vaddr) +void copy_highpage(struct page *to, struct page *from) { - struct page *page = virt_to_page(kto); + struct page *kto = page_address(to); + struct page *kfrom = page_address(from); + copy_page(kto, kfrom); - flush_dcache_page(page); + + if (system_supports_mte() && test_bit(PG_mte_tagged, &from->flags)) { + set_bit(PG_mte_tagged, &to->flags); + mte_copy_page_tags(kto, kfrom); + } +} +EXPORT_SYMBOL(copy_highpage); + +void copy_user_highpage(struct page *to, struct page *from, + unsigned long vaddr, struct vm_area_struct *vma) +{ + copy_highpage(to, from); + flush_dcache_page(to); } -EXPORT_SYMBOL_GPL(__cpu_copy_user_page); +EXPORT_SYMBOL_GPL(copy_user_highpage); void __cpu_clear_user_page(void *kaddr, unsigned long vaddr) {