Blame view

kernel/linux-imx6_3.14.28/fs/proc/kmsg.c 1.45 KB
6b13f685e   김민수   BSP 최초 추가
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
53
54
55
56
57
58
59
60
61
62
63
64
  /*
   *  linux/fs/proc/kmsg.c
   *
   *  Copyright (C) 1992  by Linus Torvalds
   *
   */
  
  #include <linux/types.h>
  #include <linux/errno.h>
  #include <linux/time.h>
  #include <linux/kernel.h>
  #include <linux/poll.h>
  #include <linux/proc_fs.h>
  #include <linux/fs.h>
  #include <linux/syslog.h>
  
  #include <asm/uaccess.h>
  #include <asm/io.h>
  
  extern wait_queue_head_t log_wait;
  
  static int kmsg_open(struct inode * inode, struct file * file)
  {
  	return do_syslog(SYSLOG_ACTION_OPEN, NULL, 0, SYSLOG_FROM_PROC);
  }
  
  static int kmsg_release(struct inode * inode, struct file * file)
  {
  	(void) do_syslog(SYSLOG_ACTION_CLOSE, NULL, 0, SYSLOG_FROM_PROC);
  	return 0;
  }
  
  static ssize_t kmsg_read(struct file *file, char __user *buf,
  			 size_t count, loff_t *ppos)
  {
  	if ((file->f_flags & O_NONBLOCK) &&
  	    !do_syslog(SYSLOG_ACTION_SIZE_UNREAD, NULL, 0, SYSLOG_FROM_PROC))
  		return -EAGAIN;
  	return do_syslog(SYSLOG_ACTION_READ, buf, count, SYSLOG_FROM_PROC);
  }
  
  static unsigned int kmsg_poll(struct file *file, poll_table *wait)
  {
  	poll_wait(file, &log_wait, wait);
  	if (do_syslog(SYSLOG_ACTION_SIZE_UNREAD, NULL, 0, SYSLOG_FROM_PROC))
  		return POLLIN | POLLRDNORM;
  	return 0;
  }
  
  
  static const struct file_operations proc_kmsg_operations = {
  	.read		= kmsg_read,
  	.poll		= kmsg_poll,
  	.open		= kmsg_open,
  	.release	= kmsg_release,
  	.llseek		= generic_file_llseek,
  };
  
  static int __init proc_kmsg_init(void)
  {
  	proc_create("kmsg", S_IRUSR, NULL, &proc_kmsg_operations);
  	return 0;
  }
  fs_initcall(proc_kmsg_init);