// SPDX-License-Identifier: GPL-2.0 /* * EFI capsule loader driver. * * Copyright 2015 Intel Corporation */ #define pr_fmt(fmt) … #include <linux/kernel.h> #include <linux/module.h> #include <linux/miscdevice.h> #include <linux/highmem.h> #include <linux/io.h> #include <linux/slab.h> #include <linux/mutex.h> #include <linux/efi.h> #include <linux/vmalloc.h> #define NO_FURTHER_WRITE_ACTION … /** * efi_free_all_buff_pages - free all previous allocated buffer pages * @cap_info: pointer to current instance of capsule_info structure * * In addition to freeing buffer pages, it flags NO_FURTHER_WRITE_ACTION * to cease processing data in subsequent write(2) calls until close(2) * is called. **/ static void efi_free_all_buff_pages(struct capsule_info *cap_info) { … } int __efi_capsule_setup_info(struct capsule_info *cap_info) { … } /** * efi_capsule_setup_info - 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 first page buffer pointer * @hdr_bytes: the total received number of bytes for efi header * * Platforms with non-standard capsule update mechanisms can override * this __weak function so they can perform any required capsule * image munging. See quark_quirk_function() for an example. **/ int __weak efi_capsule_setup_info(struct capsule_info *cap_info, void *kbuff, size_t hdr_bytes) { … } /** * 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) { … } /** * 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: * - A user space tool should start at the beginning of capsule binary and * pass data in sequentially. * - Users should close and re-open this file note in order to upload more * capsules. * - After an error returned, user should close the file and restart the * operation for the next try otherwise -EIO will be returned until the * file is closed. * - An EFI capsule header must be located at the beginning of capsule * binary file and passed in as first block data of write operation. **/ static ssize_t efi_capsule_write(struct file *file, const char __user *buff, size_t count, loff_t *offp) { … } /** * efi_capsule_release - called by file close * @inode: not used * @file: file pointer * * We will not free successfully submitted pages since efi update * requires data to be maintained across system reboot. **/ static int efi_capsule_release(struct inode *inode, struct file *file) { … } /** * 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) { … } static const struct file_operations efi_capsule_fops = …; static struct miscdevice efi_capsule_misc = …; static int __init efi_capsule_loader_init(void) { … } module_init(…) …; static void __exit efi_capsule_loader_exit(void) { … } module_exit(efi_capsule_loader_exit); MODULE_DESCRIPTION(…) …; MODULE_LICENSE(…) …;
Codebase Browser
linux