105 lines
2.6 KiB
C
105 lines
2.6 KiB
C
|
/*
|
||
|
|
* Copyright (c) 2016 Samsung Electronics Co., Ltd.
|
||
|
|
* http://www.samsung.com
|
||
|
|
*
|
||
|
|
* Samsung TN debugging code
|
||
|
|
*
|
||
|
|
* This program is free software; you can redistribute it and/or modify
|
||
|
|
* it under the terms of the GNU General Public License version 2 as
|
||
|
|
* published by the Free Software Foundation.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <linux/kernel.h>
|
||
|
|
#include <linux/uaccess.h>
|
||
|
|
#include <linux/slab.h>
|
||
|
|
#include <linux/proc_fs.h>
|
||
|
|
#include <linux/sec_debug.h>
|
||
|
|
|
||
|
|
static char *last_kmsg_buffer;
|
||
|
|
static size_t last_kmsg_size;
|
||
|
|
|
||
|
|
void sec_debug_save_last_kmsg(unsigned char *head_ptr, unsigned char *curr_ptr, size_t buf_size)
|
||
|
|
{
|
||
|
|
size_t size;
|
||
|
|
unsigned char *magickey_addr;
|
||
|
|
|
||
|
|
if (!head_ptr || !curr_ptr || head_ptr == curr_ptr) {
|
||
|
|
pr_err("%s: no data\n", __func__);
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
|
||
|
|
if ((curr_ptr - head_ptr) <= 0) {
|
||
|
|
pr_err("%s: invalid args\n", __func__);
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
size = (size_t)(curr_ptr - head_ptr);
|
||
|
|
|
||
|
|
magickey_addr = head_ptr + buf_size - (size_t)0x08;
|
||
|
|
|
||
|
|
/* provide previous log as last_kmsg */
|
||
|
|
if (*((unsigned long long *)magickey_addr) == SEC_LKMSG_MAGICKEY) {
|
||
|
|
pr_info("%s: sec_log buffer is full\n", __func__);
|
||
|
|
last_kmsg_size = (size_t)SZ_2M;
|
||
|
|
last_kmsg_buffer = kzalloc(last_kmsg_size, GFP_NOWAIT);
|
||
|
|
if (last_kmsg_size && last_kmsg_buffer) {
|
||
|
|
memcpy(last_kmsg_buffer, curr_ptr, last_kmsg_size - size);
|
||
|
|
memcpy(last_kmsg_buffer + (last_kmsg_size - size), head_ptr, size);
|
||
|
|
pr_info("%s: succeeded\n", __func__);
|
||
|
|
} else {
|
||
|
|
pr_err("%s: failed\n", __func__);
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
pr_info("%s: sec_log buffer is not full\n", __func__);
|
||
|
|
last_kmsg_size = size;
|
||
|
|
last_kmsg_buffer = kzalloc(last_kmsg_size, GFP_NOWAIT);
|
||
|
|
if (last_kmsg_size && last_kmsg_buffer) {
|
||
|
|
memcpy(last_kmsg_buffer, head_ptr, last_kmsg_size);
|
||
|
|
pr_info("%s: succeeded\n", __func__);
|
||
|
|
} else {
|
||
|
|
pr_err("%s: failed\n", __func__);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
static ssize_t sec_last_kmsg_read(struct file *file, char __user *buf,
|
||
|
|
size_t len, loff_t *offset)
|
||
|
|
{
|
||
|
|
loff_t pos = *offset;
|
||
|
|
ssize_t count;
|
||
|
|
|
||
|
|
if (pos >= last_kmsg_size)
|
||
|
|
return 0;
|
||
|
|
|
||
|
|
count = min(len, (size_t)(last_kmsg_size - pos));
|
||
|
|
if (copy_to_user(buf, last_kmsg_buffer + pos, count))
|
||
|
|
return -EFAULT;
|
||
|
|
|
||
|
|
*offset += count;
|
||
|
|
return count;
|
||
|
|
}
|
||
|
|
|
||
|
|
static const struct file_operations last_kmsg_file_ops = {
|
||
|
|
.owner = THIS_MODULE,
|
||
|
|
.read = sec_last_kmsg_read,
|
||
|
|
};
|
||
|
|
|
||
|
|
static int __init sec_last_kmsg_late_init(void)
|
||
|
|
{
|
||
|
|
struct proc_dir_entry *entry;
|
||
|
|
|
||
|
|
if (!last_kmsg_buffer)
|
||
|
|
return 0;
|
||
|
|
|
||
|
|
entry = proc_create("last_kmsg", S_IFREG | 0444,
|
||
|
|
NULL, &last_kmsg_file_ops);
|
||
|
|
if (!entry) {
|
||
|
|
pr_err("%s: failed to create proc entry\n", __func__);
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
proc_set_size(entry, last_kmsg_size);
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
late_initcall(sec_last_kmsg_late_init);
|