From patchwork Wed Oct 7 19:13:53 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kweh Hock Leong X-Patchwork-Id: 7344381 Return-Path: X-Original-To: patchwork-linux-fsdevel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 859939F443 for ; Wed, 7 Oct 2015 11:15:48 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 04F1520552 for ; Wed, 7 Oct 2015 11:15:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 848E620495 for ; Wed, 7 Oct 2015 11:15:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753141AbbJGLOe (ORCPT ); Wed, 7 Oct 2015 07:14:34 -0400 Received: from mga14.intel.com ([192.55.52.115]:3533 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752874AbbJGLO0 (ORCPT ); Wed, 7 Oct 2015 07:14:26 -0400 Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga103.fm.intel.com with ESMTP; 07 Oct 2015 04:14:25 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.17,648,1437462000"; d="scan'208";a="821226890" Received: from kweh-desk1.png.intel.com ([172.30.66.22]) by orsmga002.jf.intel.com with ESMTP; 07 Oct 2015 04:14:21 -0700 From: "Kweh, Hock Leong" To: Matt Fleming , Greg Kroah-Hartman Cc: Ong Boon Leong , LKML , linux-efi@vger.kernel.org, Sam Protsenko , Peter Jones , Andy Lutomirski , Roy Franz , Borislav Petkov , James Bottomley , Linux FS Devel , "Kweh, Hock Leong" , Fleming Matt , h.peter.anvin@intel.com Subject: [PATCH v8 2/2] efi: a misc char interface for user to update efi firmware Date: Thu, 8 Oct 2015 03:13:53 +0800 Message-Id: <1444245233-19229-3-git-send-email-hock.leong.kweh@intel.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1444245233-19229-1-git-send-email-hock.leong.kweh@intel.com> References: <1444245233-19229-1-git-send-email-hock.leong.kweh@intel.com> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Spam-Status: No, score=-5.0 required=5.0 tests=BAYES_00, DATE_IN_FUTURE_06_12, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: "Kweh, Hock Leong" Introducing a kernel module to expose capsule loader interface (misc char device file note) for user to upload capsule binaries. Example method to load the capsule binary: cat firmware.bin > /dev/efi_capsule_loader Cc: Matt Fleming Signed-off-by: Kweh, Hock Leong --- drivers/firmware/efi/Kconfig | 10 + drivers/firmware/efi/Makefile | 1 + drivers/firmware/efi/efi-capsule-loader.c | 356 +++++++++++++++++++++++++++++ 3 files changed, 367 insertions(+) create mode 100644 drivers/firmware/efi/efi-capsule-loader.c diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig index f712d47..0be8ee3 100644 --- a/drivers/firmware/efi/Kconfig +++ b/drivers/firmware/efi/Kconfig @@ -60,6 +60,16 @@ config EFI_RUNTIME_WRAPPERS config EFI_ARMSTUB bool +config EFI_CAPSULE_LOADER + tristate "EFI capsule loader" + depends on EFI + help + This option exposes a loader interface "/dev/efi_capsule_loader" for + user to load EFI capsule binary and update the EFI firmware through + system reboot. + + If unsure, say N. + endmenu config UEFI_CPER diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile index 698846e..5ab031a 100644 --- a/drivers/firmware/efi/Makefile +++ b/drivers/firmware/efi/Makefile @@ -8,3 +8,4 @@ obj-$(CONFIG_UEFI_CPER) += cper.o obj-$(CONFIG_EFI_RUNTIME_MAP) += runtime-map.o obj-$(CONFIG_EFI_RUNTIME_WRAPPERS) += runtime-wrappers.o obj-$(CONFIG_EFI_STUB) += libstub/ +obj-$(CONFIG_EFI_CAPSULE_LOADER) += efi-capsule-loader.o diff --git a/drivers/firmware/efi/efi-capsule-loader.c b/drivers/firmware/efi/efi-capsule-loader.c new file mode 100644 index 0000000..b415b4e --- /dev/null +++ b/drivers/firmware/efi/efi-capsule-loader.c @@ -0,0 +1,356 @@ +/* + * EFI capsule loader driver. + * + * Copyright 2015 Intel Corporation + * + * This file is part of the Linux kernel, and is made available under + * the terms of the GNU General Public License version 2. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include +#include + +#define DEV_NAME "efi_capsule_loader" +#define UPLOAD_DONE -1 +#define ERR_OCCURED -2 + +struct capsule_info { + char header_obtained; + int reset_type; + long index; + unsigned long count; + unsigned long total_size; + struct page **pages; + unsigned long page_count_remain; +}; + +static DEFINE_MUTEX(capsule_loader_lock); + +/** + * efi_free_all_buff_pages - free the current & all previous allocated buffer + * pages + * @file: file pointer + * @kbuff: a mapped buffer pointer + * @kbuff_page: the current execution allocated buffer page's pointer which has + * not yet assigned to pages[] array + * + * The input param can be NULL if the current execution has not allocated + * any buffer page. + **/ +static void efi_free_all_buff_pages(struct file *file, void *kbuff, + struct page *kbuff_page) +{ + struct capsule_info *cap_info = file->private_data; + + if (kbuff) + kunmap(kbuff_page); + + if (kbuff_page) + __free_page(kbuff_page); + + while (cap_info->index > 0) + __free_page(cap_info->pages[--cap_info->index]); + + kfree(cap_info->pages); + + /* indicate to the next that error had occurred */ + cap_info->index = ERR_OCCURED; +} + +/** + * efi_capsule_setup_info - to obtain the efi capsule header in the binary and + * setup capsule_info structure + * @file: file pointer + * @kbuff: a mapped 1st page buffer pointer + **/ +static ssize_t efi_capsule_setup_info(struct file *file, void *kbuff) +{ + int ret = 0; + struct capsule_info *cap_info = file->private_data; + void *temp_page; + /* reset back to the correct offset of header */ + efi_capsule_header_t *cap_hdr = kbuff - cap_info->count; + size_t pages_needed = ALIGN(cap_hdr->imagesize, PAGE_SIZE) >> + PAGE_SHIFT; + + if (pages_needed == 0) { + pr_err("%s: pages count invalid\n", __func__); + return -EINVAL; + } + + /* check if the capsule binary supported */ + mutex_lock(&capsule_loader_lock); + ret = efi_capsule_supported(cap_hdr->guid, cap_hdr->flags, + cap_hdr->imagesize, &cap_info->reset_type); + mutex_unlock(&capsule_loader_lock); + if (ret) { + pr_err("%s: efi_capsule_supported() failed\n", __func__); + return ret; + } + + cap_info->total_size = cap_hdr->imagesize; + temp_page = krealloc(cap_info->pages, pages_needed * sizeof(void *), + GFP_KERNEL | __GFP_ZERO); + if (!temp_page) { + pr_debug("%s: krealloc() failed\n", __func__); + return -ENOMEM; + } + + cap_info->pages = temp_page; + cap_info->header_obtained = 1; + return ret; +} + +/** + * efi_capsule_submit_update - invoke the efi_capsule_update API once binary + * upload done + * @file: file pointer + **/ +static ssize_t efi_capsule_submit_update(struct file *file) +{ + int ret = 0; + struct capsule_info *cap_info = file->private_data; + void *cap_hdr_temp; + + cap_hdr_temp = kmap(cap_info->pages[0]); + if (!cap_hdr_temp) { + pr_debug("%s: kmap() failed\n", __func__); + return -EFAULT; + } + + mutex_lock(&capsule_loader_lock); + ret = efi_capsule_update(cap_hdr_temp, cap_info->pages); + mutex_unlock(&capsule_loader_lock); + kunmap(cap_info->pages[0]); + if (ret) { + pr_err("%s: efi_capsule_update() failed\n", __func__); + return ret; + } + + /* indicate capsule binary uploading is done */ + cap_info->index = UPLOAD_DONE; + pr_info("%s: Successfully upload capsule file with reboot type '%s'\n", + __func__, !cap_info->reset_type ? "RESET_COLD" : + cap_info->reset_type == 1 ? "RESET_WARM" : + "RESET_SHUTDOWN"); + return ret; +} + +/** + * efi_capsule_write - store the capsule binary and pass it to + * efi_capsule_update() API in capsule.c + * @file: file pointer + * @buff: buffer pointer + * @count: number of bytes in @buff + * @offp: not use + * + * Expectation: + * - User space tool should start at the beginning of capsule binary and + * pass data in sequential. + * - User should close and re-open this file note in order to upload more + * capsules. + * - Any error occurred, user should close the file and restart the + * operation for the next try otherwise -EIO will be returned until the + * file is closed. + * - EFI capsule header must be located at the beginning of capsule binary + * file and passed in as 1st block write. + **/ +static ssize_t efi_capsule_write(struct file *file, const char __user *buff, + size_t count, loff_t *offp) +{ + int ret = 0; + struct capsule_info *cap_info = file->private_data; + struct page *kbuff_page = NULL; + void *kbuff = NULL; + size_t write_byte; + + if (count == 0) + return 0; + + /* return error while error had occurred or capsule uploading is done */ + if (cap_info->index < 0) + return -EIO; + + /* only alloc a new page when previous page is full */ + if (!cap_info->page_count_remain) { + kbuff_page = alloc_page(GFP_KERNEL); + if (!kbuff_page) { + pr_debug("%s: alloc_page() failed\n", __func__); + ret = -ENOMEM; + goto failed; + } + cap_info->page_count_remain = PAGE_SIZE; + } else { + kbuff_page = cap_info->pages[--cap_info->index]; + } + + kbuff = kmap(kbuff_page); + if (!kbuff) { + pr_debug("%s: kmap() failed\n", __func__); + ret = -EFAULT; + goto failed; + } + kbuff += PAGE_SIZE - cap_info->page_count_remain; + + /* copy capsule binary data from user space to kernel space buffer */ + write_byte = min_t(size_t, count, cap_info->page_count_remain); + if (copy_from_user(kbuff, buff, write_byte)) { + pr_debug("%s: copy_from_user() failed\n", __func__); + ret = -EFAULT; + goto failed; + } + cap_info->page_count_remain -= write_byte; + + /* setup capsule binary info structure */ + if (cap_info->header_obtained == 0 && cap_info->index == 0) { + /* handling 1st block is less than header size */ + if ((cap_info->count + write_byte) < + sizeof(efi_capsule_header_t)) { + if (!cap_info->pages) + cap_info->pages = kzalloc(sizeof(void *), + GFP_KERNEL); + } else { + ret = efi_capsule_setup_info(file, kbuff); + if (ret) + goto failed; + } + } + + cap_info->pages[cap_info->index++] = kbuff_page; + cap_info->count += write_byte; + kunmap(kbuff_page); + kbuff_page = NULL; + kbuff = NULL; + + /* submit the full binary to efi_capsule_update() API */ + if (cap_info->header_obtained && + cap_info->count >= cap_info->total_size) { + if (cap_info->count > cap_info->total_size) { + pr_err("%s: upload size exceeded header defined size\n", + __func__); + ret = -EINVAL; + goto failed; + } + + ret = efi_capsule_submit_update(file); + if (ret) + goto failed; + } + + return write_byte; + +failed: + efi_free_all_buff_pages(file, kbuff, kbuff_page); + return ret; +} + +/** + * efi_capsule_flush - called by file close or file flush + * @file: file pointer + * @id: not use + * + * If capsule being uploaded partially, calling this function will be + * treated as uploading canceled and will free up those completed buffer + * pages and then return -ECANCELED. + **/ +static int efi_capsule_flush(struct file *file, fl_owner_t id) +{ + int ret = 0; + struct capsule_info *cap_info = file->private_data; + + if (cap_info->index > 0) { + pr_err("%s: capsule upload not complete\n", __func__); + efi_free_all_buff_pages(file, NULL, NULL); + ret = -ECANCELED; + } + + return ret; +} + +/** + * efi_capsule_release - called by file close + * @inode: not use + * @file: file pointer + * + * We would not free the successful submitted buffer pages here due to + * efi update require system reboot with data maintained. + **/ +static int efi_capsule_release(struct inode *inode, struct file *file) +{ + kfree(file->private_data); + file->private_data = NULL; + return 0; +} + +/** + * efi_capsule_open - called by file open + * @inode: not use + * @file: file pointer + * + * Will allocate each capsule_info memory for each file open call. + * This provided the capability to support multiple file open feature + * where user is not needed to wait for others to finish in order to + * upload their capsule binary. + **/ +static int efi_capsule_open(struct inode *inode, struct file *file) +{ + struct capsule_info *cap_info; + + cap_info = kzalloc(sizeof(*cap_info), GFP_KERNEL); + if (!cap_info) { + pr_debug("%s: kzalloc() failed\n", __func__); + return -ENOMEM; + } + file->private_data = cap_info; + + return 0; +} + +static const struct file_operations efi_capsule_fops = { + .owner = THIS_MODULE, + .open = efi_capsule_open, + .write = efi_capsule_write, + .flush = efi_capsule_flush, + .release = efi_capsule_release, + .llseek = no_llseek, +}; + +static struct miscdevice efi_capsule_misc = { + .minor = MISC_DYNAMIC_MINOR, + .name = DEV_NAME, + .fops = &efi_capsule_fops, +}; + +static int __init efi_capsule_loader_init(void) +{ + int ret; + + mutex_init(&capsule_loader_lock); + + ret = misc_register(&efi_capsule_misc); + if (ret) { + pr_err("%s: Failed to register misc char file note\n", + __func__); + mutex_destroy(&capsule_loader_lock); + } + + return ret; +} +module_init(efi_capsule_loader_init); + +static void __exit efi_capsule_loader_exit(void) +{ + misc_deregister(&efi_capsule_misc); + mutex_destroy(&capsule_loader_lock); +} +module_exit(efi_capsule_loader_exit); + +MODULE_DESCRIPTION("EFI capsule firmware binary loader"); +MODULE_LICENSE("GPL v2");