Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/*
2 * memconsole.c
3 *
4 * Architecture-independent parts of the memory based BIOS console.
5 *
6 * Copyright 2017 Google Inc.
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License v2.0 as published by
10 * the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 */
17
18#include <linux/init.h>
19#include <linux/sysfs.h>
20#include <linux/kobject.h>
21#include <linux/module.h>
22
23#include "memconsole.h"
24
25static ssize_t (*memconsole_read_func)(char *, loff_t, size_t);
26
27static ssize_t memconsole_read(struct file *filp, struct kobject *kobp,
28 struct bin_attribute *bin_attr, char *buf,
29 loff_t pos, size_t count)
30{
31 if (WARN_ON_ONCE(!memconsole_read_func))
32 return -EIO;
33 return memconsole_read_func(buf, pos, count);
34}
35
36static struct bin_attribute memconsole_bin_attr = {
37 .attr = {.name = "log", .mode = 0444},
38 .read = memconsole_read,
39};
40
41void memconsole_setup(ssize_t (*read_func)(char *, loff_t, size_t))
42{
43 memconsole_read_func = read_func;
44}
45EXPORT_SYMBOL(memconsole_setup);
46
47int memconsole_sysfs_init(void)
48{
49 return sysfs_create_bin_file(firmware_kobj, &memconsole_bin_attr);
50}
51EXPORT_SYMBOL(memconsole_sysfs_init);
52
53void memconsole_exit(void)
54{
55 sysfs_remove_bin_file(firmware_kobj, &memconsole_bin_attr);
56}
57EXPORT_SYMBOL(memconsole_exit);
58
59MODULE_AUTHOR("Google, Inc.");
60MODULE_LICENSE("GPL");