From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965501AbbJ1J7a (ORCPT ); Wed, 28 Oct 2015 05:59:30 -0400 Received: from mga11.intel.com ([192.55.52.93]:18550 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965466AbbJ1J7Z (ORCPT ); Wed, 28 Oct 2015 05:59:25 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.20,209,1444719600"; d="scan'208";a="673418424" 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 v9 1/1] efi: a misc char interface for user to update efi firmware Date: Thu, 29 Oct 2015 01:58:57 +0800 Message-Id: <1446055138-26047-2-git-send-email-hock.leong.kweh@intel.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1446055138-26047-1-git-send-email-hock.leong.kweh@intel.com> References: <1446055138-26047-1-git-send-email-hock.leong.kweh@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 This patch also export efi_capsule_supported() function symbol for verifying the submitted capsule header in this kernel module. Cc: Matt Fleming Signed-off-by: Kweh, Hock Leong --- drivers/firmware/efi/Kconfig | 10 drivers/firmware/efi/Makefile | 1 drivers/firmware/efi/capsule.c | 1 drivers/firmware/efi/efi-capsule-loader.c | 356 +++++++++++++++++++++++++++++ 4 files changed, 368 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/capsule.c b/drivers/firmware/efi/capsule.c index d8cd75c0..738d437 100644 --- a/drivers/firmware/efi/capsule.c +++ b/drivers/firmware/efi/capsule.c @@ -101,6 +101,7 @@ out: kfree(capsule); return rv; } +EXPORT_SYMBOL_GPL(efi_capsule_supported); /** * efi_capsule_update - send a capsule to the firmware diff --git a/drivers/firmware/efi/efi-capsule-loader.c b/drivers/firmware/efi/efi-capsule-loader.c new file mode 100644 index 0000000..23f7618 --- /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 { + bool header_obtained; + int reset_type; + long index; + size_t count; + size_t total_size; + struct page **pages; + size_t page_bytes_remain; +}; + +static DEFINE_MUTEX(capsule_loader_lock); + +/** + * efi_free_all_buff_pages - free all previous allocated buffer pages + * @cap_info: pointer to current instance of capsule_info structure + * + * Besides freeing the buffer pages, it also flagged an ERR_OCCURED + * flag for indicating to the next write entries that there is a flaw + * happened and any subsequence actions are not valid unless close(2). + **/ +static void efi_free_all_buff_pages(struct capsule_info *cap_info) +{ + 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 + * @cap_info: pointer to current instance of capsule_info structure + * @kbuff: a mapped 1st page buffer pointer + * @hdr_bytes: the total bytes of received efi header + **/ +static ssize_t efi_capsule_setup_info(struct capsule_info *cap_info, + void *kbuff, size_t hdr_bytes) +{ + int ret; + void *temp_page; + + /* Handling 1st block is less than header size */ + if (hdr_bytes < sizeof(efi_capsule_header_t)) { + if (!cap_info->pages) { + cap_info->pages = kzalloc(sizeof(void *), GFP_KERNEL); + if (!cap_info->pages) { + pr_debug("%s: kzalloc() failed\n", __func__); + return -ENOMEM; + } + } + } else { + /* 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 0; +} + +/** + * efi_capsule_submit_update - invoke the efi_capsule_update API once binary + * upload done + * @cap_info: pointer to current instance of capsule_info structure + **/ +static ssize_t efi_capsule_submit_update(struct capsule_info *cap_info) +{ + int ret; + 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 0; +} + +/** + * efi_capsule_write - store the capsule binary and pass it to + * efi_capsule_update() API + * @file: file pointer + * @buff: buffer pointer + * @count: number of bytes in @buff + * @offp: not used + * + * 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_bytes_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_bytes_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 fail_freepage; + } + kbuff += PAGE_SIZE - cap_info->page_bytes_remain; + + /* Copy capsule binary data from user space to kernel space buffer */ + write_byte = min_t(size_t, count, cap_info->page_bytes_remain); + if (copy_from_user(kbuff, buff, write_byte)) { + pr_debug("%s: copy_from_user() failed\n", __func__); + ret = -EFAULT; + goto fail_unmap; + } + cap_info->page_bytes_remain -= write_byte; + + /* Setup capsule binary info structure */ + if (!cap_info->header_obtained) { + ret = efi_capsule_setup_info(cap_info, kbuff, + cap_info->count + write_byte); + if (ret) + goto fail_unmap; + } + + cap_info->pages[cap_info->index++] = kbuff_page; + cap_info->count += write_byte; + kunmap(kbuff_page); + + /* 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(cap_info); + if (ret) + goto failed; + } + + return write_byte; + +fail_unmap: + kunmap(kbuff_page); +fail_freepage: + __free_page(kbuff_page); +failed: + efi_free_all_buff_pages(cap_info); + return ret; +} + +/** + * efi_capsule_flush - called by file close or file flush + * @file: file pointer + * @id: not used + * + * 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(cap_info); + ret = -ECANCELED; + } + + return ret; +} + +/** + * efi_capsule_release - called by file close + * @inode: not used + * @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 used + * @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"); -- 1.7.9.5