1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* memconsole.c
*
* Architecture-independent parts of the memory based BIOS console.
*
* Copyright 2017 Google Inc.
*/
#include <linux/init.h>
#include <linux/sysfs.h>
#include <linux/kobject.h>
#include <linux/module.h>
#include "memconsole.h"
static ssize_t (*memconsole_read_func)(char *, loff_t, size_t);
static ssize_t memconsole_read(struct file *filp, struct kobject *kobp,
struct bin_attribute *bin_attr, char *buf,
loff_t pos, size_t count)
{
if (WARN_ON_ONCE(!memconsole_read_func))
return -EIO;
return memconsole_read_func(buf, pos, count);
}
static struct bin_attribute memconsole_bin_attr = {
.attr = {.name = "log", .mode = 0444},
.read = memconsole_read,
};
void memconsole_setup(ssize_t (*read_func)(char *, loff_t, size_t))
{
memconsole_read_func = read_func;
}
EXPORT_SYMBOL(memconsole_setup);
int memconsole_sysfs_init(void)
{
return sysfs_create_bin_file(firmware_kobj, &memconsole_bin_attr);
}
EXPORT_SYMBOL(memconsole_sysfs_init);
void memconsole_exit(void)
{
sysfs_remove_bin_file(firmware_kobj, &memconsole_bin_attr);
}
EXPORT_SYMBOL(memconsole_exit);
MODULE_AUTHOR("Google, Inc.");
MODULE_LICENSE("GPL");
|
