From patchwork Wed Jan 15 14:33:21 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Morse X-Patchwork-Id: 11335009 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 7762013A0 for ; Wed, 15 Jan 2020 14:34:19 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 563DA2465A for ; Wed, 15 Jan 2020 14:34:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="X26LfBlB" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 563DA2465A 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=bombadil.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=qM6aHN90XTb0TBRKpzo40/sNVimTevIWjtIRmx20068=; b=X26LfBlBiP6llT 6MBE9Pi7KL/sE2DfsI+433/3PVcKWq2npkGd3TeoIRZqqMysdR9qNOZYV6ntGp3sfk9nG+6eByYKp /wo/ueKtSlvDcM6rwdj33QR8h7qDhfelbLfF8GLqxUmUgzY5qcebKjw4DAMvF3vHzo6zCr0qtG1ZY y3oGMJR7azeuI/HfvcwuOqsNsituCTeLyomwGjLz8S+t8TjDS1JzIYK/cNz502D8f1Gz9nBX3ZbMS uoMIoiv9r7ZUvTAqm31fAF6vFRCmEM4j3gbI91vVpChz5Mwvnv87jDGI31nMKXX3fXOzOKnEE9Wpx 7As5KwtnbLR3xxf5qJ3Q==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1irjkP-00025v-Lt; Wed, 15 Jan 2020 14:34:17 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1irjji-0001Sw-Sw for linux-arm-kernel@lists.infradead.org; Wed, 15 Jan 2020 14:33:43 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 8283912FC; Wed, 15 Jan 2020 06:33:34 -0800 (PST) Received: from eglon.cambridge.arm.com (eglon.cambridge.arm.com [10.1.196.105]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 1303A3F68E; Wed, 15 Jan 2020 06:33:33 -0800 (PST) From: James Morse To: Pavel Tatashin Subject: [RFC PATCH 2/3] arm64: hibernate: Split create_safe_exec_page() and its mapping code Date: Wed, 15 Jan 2020 14:33:21 +0000 Message-Id: <20200115143322.214247-3-james.morse@arm.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200115143322.214247-1-james.morse@arm.com> References: <20200115143322.214247-1-james.morse@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200115_063335_016650_9FA7D2AE X-CRM114-Status: GOOD ( 14.88 ) X-Spam-Score: 0.0 (/) X-Spam-Report: SpamAssassin version 3.4.2 on bombadil.infradead.org summary: Content analysis details: (0.0 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at https://www.dnswl.org/, no trust [217.140.110.172 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 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-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org Kexec wants to share hibernate's page table setup code, but needs its memory-copy buffer idmapped as it also has to turn the MMU off. Split the copy of this buffer from the code that maps it. Signed-off-by: James Morse --- arch/arm64/kernel/hibernate.c | 57 +++++++++++++++++++++-------------- 1 file changed, 34 insertions(+), 23 deletions(-) diff --git a/arch/arm64/kernel/hibernate.c b/arch/arm64/kernel/hibernate.c index a96b2921d22c..7f8cb7596f9e 100644 --- a/arch/arm64/kernel/hibernate.c +++ b/arch/arm64/kernel/hibernate.c @@ -183,19 +183,9 @@ int arch_hibernation_header_restore(void *addr) EXPORT_SYMBOL(arch_hibernation_header_restore); /* - * Copies length bytes, starting at src_start into an new page, - * perform cache maintentance, then maps it at the specified address low - * address as executable. - * - * This is used by hibernate to copy the code it needs to execute when - * overwriting the kernel text. This function generates a new set of page - * tables, which it loads into ttbr0. - * - * Length is provided as we probably only want 4K of data, even on a 64K - * page system. + * Create a set of page tables that map page to dst_addr. */ -static int create_safe_exec_page(void *src_start, size_t length, - unsigned long dst_addr, +static int create_single_mapping(unsigned long page, unsigned long dst_addr, phys_addr_t *phys_dst_addr, void *(*allocator)(gfp_t mask), gfp_t mask) @@ -206,15 +196,6 @@ static int create_safe_exec_page(void *src_start, size_t length, pud_t *pudp; pmd_t *pmdp; pte_t *ptep; - unsigned long dst = (unsigned long)allocator(mask); - - if (!dst) { - rc = -ENOMEM; - goto out; - } - - memcpy((void *)dst, src_start, length); - __flush_icache_range(dst, dst + length); trans_pgd = allocator(mask); if (!trans_pgd) { @@ -253,7 +234,7 @@ static int create_safe_exec_page(void *src_start, size_t length, } ptep = pte_offset_kernel(pmdp, dst_addr); - set_pte(ptep, pfn_pte(virt_to_pfn(dst), PAGE_KERNEL_EXEC)); + set_pte(ptep, pfn_pte(virt_to_pfn(page), PAGE_KERNEL_EXEC)); /* * Load our new page tables. A strict BBM approach requires that we @@ -272,12 +253,42 @@ static int create_safe_exec_page(void *src_start, size_t length, write_sysreg(phys_to_ttbr(virt_to_phys(pgdp)), ttbr0_el1); isb(); - *phys_dst_addr = virt_to_phys((void *)dst); + *phys_dst_addr = virt_to_phys((void *)page); out: return rc; } +/* + * Copies length bytes, starting at src_start into an new page, + * perform cache maintentance, then maps it at the specified address low + * address as executable. + * + * This is used by hibernate to copy the code it needs to execute when + * overwriting the kernel text. This function generates a new set of page + * tables, which it loads into ttbr0. + * + * Length is provided as we probably only want 4K of data, even on a 64K + * page system. + */ +static int create_safe_exec_page(void *src_start, size_t length, + unsigned long dst_addr, + phys_addr_t *phys_dst_addr, + void *(*allocator)(gfp_t mask), + gfp_t mask) +{ + unsigned long page = (unsigned long)allocator(mask); + + if (!page) + return -ENOMEM; + + memcpy((void *)page, src_start, length); + __flush_icache_range(page, page + length); + + return create_single_mapping(page, dst_addr, phys_dst_addr, + allocator, gfp_t mask) +} + #define dcache_clean_range(start, end) __flush_dcache_area(start, (end - start)) int swsusp_arch_suspend(void)