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=-8.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 22DD8C004D5 for ; Thu, 27 Sep 2018 08:51:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CAB3A2157C for ; Thu, 27 Sep 2018 08:51:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=linaro.org header.i=@linaro.org header.b="bovG80Cm" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CAB3A2157C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727340AbeI0PIL (ORCPT ); Thu, 27 Sep 2018 11:08:11 -0400 Received: from mail-wm1-f67.google.com ([209.85.128.67]:51165 "EHLO mail-wm1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726947AbeI0PIL (ORCPT ); Thu, 27 Sep 2018 11:08:11 -0400 Received: by mail-wm1-f67.google.com with SMTP id s12-v6so5032584wmc.0 for ; Thu, 27 Sep 2018 01:51:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=f8rCgirc+Q/Pjj+hezpx+WshLqF7c604zeE4cCjQ4cU=; b=bovG80CmbjL84b5Zsj4eHC7ELIy3ILRfjn7nny+sOwsD9OQLDif7BtAPKn1cmccbAj CD313OwFymTWeSWL4w7q/j8EPuOxM2JEzK63Mk76d/1b7GDHa3zPkBDuVJf17EC+OFX1 fFHfqSiPqdljW9o7Gi73hRRYpGRCiY3yNMjSc= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=f8rCgirc+Q/Pjj+hezpx+WshLqF7c604zeE4cCjQ4cU=; b=XTQcimw5kNk6u5OZEtZWjL+W99Vq6h0pXcNrWc4R8On50FTTi1hHX4TizunOhplKDX UzxxOM/whaGOgqTD7raUW/5wK2noGkcWvQMw8faOljpS4mPQbRSMmSmlpE25kjy3o70y GhsULyG7f9tbvkNIaYh9xH/y1aRNvp5mCtj1tX+DsLGQW6wA95BkghEyT+UUYVIzSooW 4MVK4ZADJPKK3DgkS3JeK7cPsTKnnnhPn7ILChGLxXQj3DSBHwMOJJMuyWPprJgMsAzX hPMp1ra9oi7mo2H0NV53IYugUWYBemCpgihtvyQTRLBoDy1ZE8maYB3CH/drExkH0ogF cP3g== X-Gm-Message-State: ABuFfoipX+e/XYTl5AcZROtsphrv783+0mwfP4+7zzM1Z8HW73CeC07o eDUZ/laSjCAgJ8sYjjktHh7WujUPk9g= X-Google-Smtp-Source: ACcGV63ptguOmZMBM9fmPQ7yNyQRaoh6Vx1ktDY1sm98Gm70juebu/aT4B0SRbzByL0DeyjZfNccPQ== X-Received: by 2002:a1c:8a55:: with SMTP id m82-v6mr6884527wmd.70.1538038260353; Thu, 27 Sep 2018 01:51:00 -0700 (PDT) Received: from rev03.home ([2a01:cb1d:112:6f00:546e:3c44:5966:2f5e]) by smtp.gmail.com with ESMTPSA id p11-v6sm1304055wrd.74.2018.09.27.01.50.59 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 27 Sep 2018 01:50:59 -0700 (PDT) From: Ard Biesheuvel To: linux-kernel@vger.kernel.org, Ingo Molnar , Thomas Gleixner Cc: Ard Biesheuvel , linux-efi@vger.kernel.org, Aaron Ma , Alistair Strachan , Ben Hutchings , Bhupesh Sharma , Hans de Goede , Ivan Hu , Jeremy Linton , Marc Zyngier , Matt Fleming , Peter Robinson , Sai Praneeth Prakhya , Sebastian Andrzej Siewior , Stefan Agner Subject: [PATCH 03/11] efi: add API to reserve memory persistently across kexec reboot Date: Thu, 27 Sep 2018 10:50:30 +0200 Message-Id: <20180927085039.8391-4-ard.biesheuvel@linaro.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180927085039.8391-1-ard.biesheuvel@linaro.org> References: <20180927085039.8391-1-ard.biesheuvel@linaro.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add kernel plumbing to reserve memory regions persistently on a EFI system by adding entries to the MEMRESERVE linked list. Tested-by: Jeremy Linton Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/efi.c | 32 ++++++++++++++++++++++++++++++++ include/linux/efi.h | 1 + 2 files changed, 33 insertions(+) diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 688132ac8a0a..249eb70691b0 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -962,6 +962,38 @@ bool efi_is_table_address(unsigned long phys_addr) return false; } +static DEFINE_SPINLOCK(efi_mem_reserve_persistent_lock); + +int efi_mem_reserve_persistent(phys_addr_t addr, u64 size) +{ + struct linux_efi_memreserve *rsv, *parent; + + if (efi.mem_reserve == EFI_INVALID_TABLE_ADDR) + return -ENODEV; + + rsv = kmalloc(sizeof(*rsv), GFP_KERNEL); + if (!rsv) + return -ENOMEM; + + parent = memremap(efi.mem_reserve, sizeof(*rsv), MEMREMAP_WB); + if (!parent) { + kfree(rsv); + return -ENOMEM; + } + + rsv->base = addr; + rsv->size = size; + + spin_lock(&efi_mem_reserve_persistent_lock); + rsv->next = parent->next; + parent->next = __pa(rsv); + spin_unlock(&efi_mem_reserve_persistent_lock); + + memunmap(parent); + + return 0; +} + #ifdef CONFIG_KEXEC static int update_efi_random_seed(struct notifier_block *nb, unsigned long code, void *unused) diff --git a/include/linux/efi.h b/include/linux/efi.h index a5cb580472c5..22e4de9d3700 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -1043,6 +1043,7 @@ extern int __init efi_uart_console_only (void); extern u64 efi_mem_desc_end(efi_memory_desc_t *md); extern int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md); extern void efi_mem_reserve(phys_addr_t addr, u64 size); +extern int efi_mem_reserve_persistent(phys_addr_t addr, u64 size); extern void efi_initialize_iomem_resources(struct resource *code_resource, struct resource *data_resource, struct resource *bss_resource); extern void efi_reserve_boot_services(void); -- 2.18.0