From patchwork Sat Aug 17 02:46:18 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pasha Tatashin X-Patchwork-Id: 11098493 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 1CD8217E2 for ; Sat, 17 Aug 2019 02:46:41 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0A8A128AA4 for ; Sat, 17 Aug 2019 02:46:41 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id F301528AA2; Sat, 17 Aug 2019 02:46:40 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.7 required=2.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6954E28AA4 for ; Sat, 17 Aug 2019 02:46:40 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 80F356B026D; Fri, 16 Aug 2019 22:46:37 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 7C27F6B026E; Fri, 16 Aug 2019 22:46:37 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 59D256B026F; Fri, 16 Aug 2019 22:46:37 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0095.hostedemail.com [216.40.44.95]) by kanga.kvack.org (Postfix) with ESMTP id 39CC96B026D for ; Fri, 16 Aug 2019 22:46:37 -0400 (EDT) Received: from smtpin29.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with SMTP id C1A5C180C2E61 for ; Sat, 17 Aug 2019 02:46:36 +0000 (UTC) X-FDA: 75830381592.29.music49_90f978055774c X-HE-Tag: music49_90f978055774c X-Filterd-Recvd-Size: 8014 Received: from mail-qt1-f193.google.com (mail-qt1-f193.google.com [209.85.160.193]) by imf07.hostedemail.com (Postfix) with ESMTP for ; Sat, 17 Aug 2019 02:46:36 +0000 (UTC) Received: by mail-qt1-f193.google.com with SMTP id j15so8155063qtl.13 for ; Fri, 16 Aug 2019 19:46:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=fhpOZXqdUBODzNYqQty59G5Ge7iC8PlIDy+5W4I7/qk=; b=mBM/N/z8yGTKkYzwBN4o/dCrlkPlU17gfdIIzSulgS6UObI37vB1wBM5E6QzN8Edol +ZIF+vG/LQ4sxc0fhJFMx1EUVqlrj1DZKhZOG5CG+2qnASJdJfF++BFPASeRZHsrOQ7l 5f5Lc2n5wxaoFUY9/BftGTkGUIh93/1fDGukg46wRC7GIydl3rlFzVY7RYr8PU6ldDDJ T2/7MEX8je/x6UAz61qYNb9xAA4NihykJGICQtRl9NHdCGBGDJiuoKt5p6G9UGaGsalu ARbq1ne4gYamC8J8nKiChRzS3vCLuqR2484D9RiHFr+NU6SCL7isdVmTwg3yDP1oz/ig Fbzw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=fhpOZXqdUBODzNYqQty59G5Ge7iC8PlIDy+5W4I7/qk=; b=EWlkqTJFNqZ13g3flF6DGmN2XXO5Kf+z4dycuSP28bYDAjsr3KUliRLil9DINyRENU R0BGZxPwWRUWYy5Mr1gFmPhJevjuDM+jT8pHy0LOj69FDMSuBCHy1GUC7l0yQwjE+aLk NETdKL9D/p0tp+IAkIaOXqNjBsoruQH7gAMeESByHyBPmOirZPuVRd3ZDz7+q2g7uE0X fik0RyXsHCjoMrn28Rni7AxgKcl5MLs1CXEG2RT13nLlJZKR7+O+GAF8ly8VPjWUX4tu ziyuUDubC8Q0ZttdheBXkoIy7W0eFLrWe7sICXBNHjLP3lcDpP/ar7Ya1gYZN+JA+3Er DAyw== X-Gm-Message-State: APjAAAWXc5+Vpf05WzZYsauHsP9EpbzAPvBDm/GrUWCjZ6QEAcBlTE+R kAgmNoPai8V08oUftqo3QVB2Vw== X-Google-Smtp-Source: APXvYqwmnAgW0ugL2Xh/QQG6ta19bkx2PHnTpQKH7KpRdc000K+gJIFau3+/d7lsbnc3Od8y2BFYyw== X-Received: by 2002:a0c:d251:: with SMTP id o17mr3892714qvh.109.1566009995607; Fri, 16 Aug 2019 19:46:35 -0700 (PDT) Received: from localhost.localdomain (c-73-69-118-222.hsd1.nh.comcast.net. [73.69.118.222]) by smtp.gmail.com with ESMTPSA id o9sm3454657qtr.71.2019.08.16.19.46.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 16 Aug 2019 19:46:35 -0700 (PDT) From: Pavel Tatashin To: pasha.tatashin@soleen.com, jmorris@namei.org, sashal@kernel.org, ebiederm@xmission.com, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, corbet@lwn.net, catalin.marinas@arm.com, will@kernel.org, linux-arm-kernel@lists.infradead.org, marc.zyngier@arm.com, james.morse@arm.com, vladimir.murzin@arm.com, matthias.bgg@gmail.com, bhsharma@redhat.com, linux-mm@kvack.org Subject: [PATCH v2 03/14] arm64, hibernate: add trans_table public functions Date: Fri, 16 Aug 2019 22:46:18 -0400 Message-Id: <20190817024629.26611-4-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.22.1 In-Reply-To: <20190817024629.26611-1-pasha.tatashin@soleen.com> References: <20190817024629.26611-1-pasha.tatashin@soleen.com> MIME-Version: 1.0 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: X-Virus-Scanned: ClamAV using ClamSMTP trans_table_create_copy() and trans_table_map_page() are going to be the basis for public interface of new subsystem that handles page tables for cases which are between kernels: kexec, and hibernate. Signed-off-by: Pavel Tatashin --- arch/arm64/kernel/hibernate.c | 96 ++++++++++++++++++++++------------- 1 file changed, 61 insertions(+), 35 deletions(-) diff --git a/arch/arm64/kernel/hibernate.c b/arch/arm64/kernel/hibernate.c index 96b6f8da7e49..449d69b5651c 100644 --- a/arch/arm64/kernel/hibernate.c +++ b/arch/arm64/kernel/hibernate.c @@ -182,39 +182,15 @@ 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. - */ -static int create_safe_exec_page(void *src_start, size_t length, - unsigned long dst_addr, - phys_addr_t *phys_dst_addr) +int trans_table_map_page(pgd_t *trans_table, void *page, + unsigned long dst_addr, + pgprot_t pgprot) { - void *page = (void *)get_safe_page(GFP_ATOMIC); - pgd_t *trans_table; pgd_t *pgdp; pud_t *pudp; pmd_t *pmdp; pte_t *ptep; - if (!page) - return -ENOMEM; - - memcpy((void *)page, src_start, length); - __flush_icache_range((unsigned long)page, (unsigned long)page + length); - - trans_table = (void *)get_safe_page(GFP_ATOMIC); - if (!trans_table) - return -ENOMEM; - pgdp = pgd_offset_raw(trans_table, dst_addr); if (pgd_none(READ_ONCE(*pgdp))) { pudp = (void *)get_safe_page(GFP_ATOMIC); @@ -242,6 +218,44 @@ 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(page), PAGE_KERNEL_EXEC)); + return 0; +} + +/* + * 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 *page = (void *)get_safe_page(GFP_ATOMIC); + pgd_t *trans_table; + int rc; + + if (!page) + return -ENOMEM; + + memcpy(page, src_start, length); + __flush_icache_range((unsigned long)page, (unsigned long)page + length); + + trans_table = (void *)get_safe_page(GFP_ATOMIC); + if (!trans_table) + return -ENOMEM; + + rc = trans_table_map_page(trans_table, page, dst_addr, + PAGE_KERNEL_EXEC); + if (rc) + return rc; + /* * Load our new page tables. A strict BBM approach requires that we * ensure that TLBs are free of any entries that may overlap with the @@ -259,7 +273,7 @@ static int create_safe_exec_page(void *src_start, size_t length, write_sysreg(phys_to_ttbr(virt_to_phys(trans_table)), ttbr0_el1); isb(); - *phys_dst_addr = virt_to_phys((void *)page); + *phys_dst_addr = virt_to_phys(page); return 0; } @@ -462,6 +476,24 @@ static int copy_page_tables(pgd_t *dst_pgdp, unsigned long start, return 0; } +int trans_table_create_copy(pgd_t **dst_pgdp, unsigned long start, + unsigned long end) +{ + int rc; + pgd_t *trans_table = (pgd_t *)get_safe_page(GFP_ATOMIC); + + if (!trans_table) { + pr_err("Failed to allocate memory for temporary page tables.\n"); + return -ENOMEM; + } + + rc = copy_page_tables(trans_table, start, end); + if (!rc) + *dst_pgdp = trans_table; + + return rc; +} + /* * Setup then Resume from the hibernate image using swsusp_arch_suspend_exit(). * @@ -483,13 +515,7 @@ int swsusp_arch_resume(void) * Create a second copy of just the linear map, and use this when * restoring. */ - tmp_pg_dir = (pgd_t *)get_safe_page(GFP_ATOMIC); - if (!tmp_pg_dir) { - pr_err("Failed to allocate memory for temporary page tables.\n"); - rc = -ENOMEM; - goto out; - } - rc = copy_page_tables(tmp_pg_dir, PAGE_OFFSET, 0); + rc = trans_table_create_copy(&tmp_pg_dir, PAGE_OFFSET, 0); if (rc) goto out;