forked from luck/tmp_suning_uos_patched
1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
75 lines
1.5 KiB
C
75 lines
1.5 KiB
C
/*
|
|
* The USB Monitor, inspired by Dave Harding's USBMon.
|
|
*
|
|
* This is the 's' or 'stat' reader which debugs usbmon itself.
|
|
* Note that this code blows through locks, so make sure that
|
|
* /dbg/usbmon/0s is well protected from non-root users.
|
|
*
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/usb.h>
|
|
#include <asm/uaccess.h>
|
|
|
|
#include "usb_mon.h"
|
|
|
|
#define STAT_BUF_SIZE 80
|
|
|
|
struct snap {
|
|
int slen;
|
|
char str[STAT_BUF_SIZE];
|
|
};
|
|
|
|
static int mon_stat_open(struct inode *inode, struct file *file)
|
|
{
|
|
struct mon_bus *mbus;
|
|
struct snap *sp;
|
|
|
|
if ((sp = kmalloc(sizeof(struct snap), GFP_KERNEL)) == NULL)
|
|
return -ENOMEM;
|
|
|
|
mbus = inode->u.generic_ip;
|
|
|
|
sp->slen = snprintf(sp->str, STAT_BUF_SIZE,
|
|
"nreaders %d text_lost %u\n",
|
|
mbus->nreaders, mbus->cnt_text_lost);
|
|
|
|
file->private_data = sp;
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t mon_stat_read(struct file *file, char __user *buf,
|
|
size_t nbytes, loff_t *ppos)
|
|
{
|
|
struct snap *sp = file->private_data;
|
|
loff_t pos = *ppos;
|
|
int cnt;
|
|
|
|
if (pos < 0 || pos >= sp->slen)
|
|
return 0;
|
|
if (nbytes == 0)
|
|
return 0;
|
|
if ((cnt = sp->slen - pos) > nbytes)
|
|
cnt = nbytes;
|
|
if (copy_to_user(buf, sp->str + pos, cnt))
|
|
return -EFAULT;
|
|
*ppos = pos + cnt;
|
|
return cnt;
|
|
}
|
|
|
|
static int mon_stat_release(struct inode *inode, struct file *file)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
struct file_operations mon_fops_stat = {
|
|
.owner = THIS_MODULE,
|
|
.open = mon_stat_open,
|
|
.llseek = no_llseek,
|
|
.read = mon_stat_read,
|
|
/* .write = mon_stat_write, */
|
|
/* .poll = mon_stat_poll, */
|
|
/* .ioctl = mon_stat_ioctl, */
|
|
.release = mon_stat_release,
|
|
};
|