Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  * The USB Monitor, inspired by Dave Harding's USBMon.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5)  * This is the 's' or 'stat' reader which debugs usbmon itself.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6)  * Note that this code blows through locks, so make sure that
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7)  * /dbg/usbmon/0s is well protected from non-root users.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/export.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/usb.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/fs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/uaccess.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #include "usb_mon.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) #define STAT_BUF_SIZE  80
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) struct snap {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) 	int slen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 	char str[STAT_BUF_SIZE];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) static int mon_stat_open(struct inode *inode, struct file *file)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 	struct mon_bus *mbus;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 	struct snap *sp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 	sp = kmalloc(sizeof(struct snap), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 	if (sp == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 		return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 	mbus = inode->i_private;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 	sp->slen = snprintf(sp->str, STAT_BUF_SIZE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 	    "nreaders %d events %u text_lost %u\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 	    mbus->nreaders, mbus->cnt_events, mbus->cnt_text_lost);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 	file->private_data = sp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) static ssize_t mon_stat_read(struct file *file, char __user *buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 				size_t nbytes, loff_t *ppos)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 	struct snap *sp = file->private_data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) 	return simple_read_from_buffer(buf, nbytes, ppos, sp->str, sp->slen);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) static int mon_stat_release(struct inode *inode, struct file *file)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) 	struct snap *sp = file->private_data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) 	file->private_data = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) 	kfree(sp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) const struct file_operations mon_fops_stat = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 	.owner =	THIS_MODULE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) 	.open =		mon_stat_open,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) 	.llseek =	no_llseek,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 	.read =		mon_stat_read,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) 	/* .write =	mon_stat_write, */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) 	/* .poll =		mon_stat_poll, */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) 	/* .unlocked_ioctl =	mon_stat_ioctl, */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) 	.release =	mon_stat_release,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) };