[Linux] Linux实现驱动模块传参过程解析

#include <linux/init.h>
#include <linux/module.h>
 
static char *p_name = "Usr";
module_param(p_name, charp, S_IRUGO);
MODULE_PARM_DESC(p_name, "This is a char * string.");
 
static int __init hi_init(void)
{
  printk(KERN_INFO "Hi enter %s\n",p_name);
  return 0;
}
module_init(hi_init);
 
static void __exit hi_exit(void)
{
  printk(KERN_INFO "Hi exit %s\n ",p_name);
}
module_exit(hi_exit);
 
MODULE_AUTHOR(" libra13179 ");
MODULE_LICENSE("GPL v2");

KVERS = $(shell uname -r)
 
# Kernel modules
obj-m += hi.o
 
# Specify flags for the module compilation.
#EXTRA_CFLAGS=-g -O0
 
build: kernel_modules
 
kernel_modules:
  make -C /lib/modules/$(KVERS)/build M=$(CURDIR) modules
#  @echo $(KVERS)
 
clean:
  make -C /lib/modules/$(KVERS)/build M=$(CURDIR) clean

root@lin-virtual-machine:/home/lin/hi# insmod ./hi.ko
root@lin-virtual-machine:/home/lin/hi# cat /var/log/syslog | grep Hi
...
Jul 25 15:11:38 lin-virtual-machine kernel: [ 203.238178] Hi enter Usr
...

root@lin-virtual-machine:/home/lin/hi# cat /sys/module/hi/parameters/p_name
God