kobject的一个例子

#include
#include
#include
#include
#include
#include
#include
#include

MODULE_AUTHOR("yangweihao");
MODULE_LICENSE("Dual BSD/GPL");

 

 struct kobject *kobj;
 struct kobject *ywhkobj;
 char *ywhname;

 

void obj_test_release(struct kobject *kobject);

ssize_t ywh_test_show(struct kobject * kobject,struct attribute * attr,char * buf)
{
 printk("have show .\n");
 printk("attrname:%s .\n",attr->name);
 sprintf(buf,"%s\n",attr->name);
 return strlen(attr->name)+2;
}

ssize_t ywh_test_store(struct kobject * kobject,struct attribute * attr,char * buf,size_t count)
{
 printk("havwstore\n");
 kfree(ywhname);
 ywhname = kmalloc(count,GFP_KERNEL);
 if(!ywhname)
 {
  printk("kmalloc error\n");
  return ENOMEM;
 }
 for(;*buf !='\0';buf++)
 {
  *(ywhname)++ = *buf;
 }
 *(ywhname) = '\0';
 ywhname = ywhname - count;
 attr->name = ywhname;

 printk("write: %s\n",attr->name);
 
 return count;
}
/*
 默认属性添加
*/
struct attribute test_attr ={
 .name = "yangweihao",
 .mode = S_IRWXUGO,
};

static struct attribute *def_attrs[] ={
 &test_attr,
 NULL
};

struct sysfs_ops obj_test_sysops ={
 .show = ywh_test_show,
 .store = ywh_test_store
};

struct kobj_type ktype = {
 .release = obj_test_release,
 .sysfs_ops = &obj_test_sysops,
 .default_attrs= def_attrs
};

void obj_test_release(struct kobject * kobject)
{
 printk("kobject_test: release .\n");
}

static int kobject_test_init()
{
 printk("kobject test init.\n");
 kobj = kmalloc(sizeof(struct kobject),GFP_KERNEL);
 ywhkobj= kmalloc(sizeof(struct kobject),GFP_KERNEL);
 ywhname = kmalloc(0,GFP_KERNEL);
 if(!kobj)
 {
  printk("kmalloc error\n");
  return ENOMEM;
 }
 memset(kobj,0,sizeof(struct kobject));
 memset(ywhkobj,0,sizeof(struct kobject));
 
 kobject_init_and_add(kobj,&ktype,NULL,"ywh");
 kobject_init_and_add(ywhkobj,&ktype,kobj,"hlp");
 
 return 0;
}

static int kobject_test_exit()
{
 printk("kobject test exit.\n");
 kobject_del(kobj);
 kfree(kobj);
 kfree(ywhkobj);
 kfree(ywhname);
 return 0;
}

module_init(kobject_test_init);
module_exit(kobject_test_exit);

 

运行如下：

[root@FriendlyARM /sys]# ls
block     class     devices   fs        module
bus       dev       firmware  kernel    ywh

[root@FriendlyARM ywh]# ls
hlp         yangweihao

[root@FriendlyARM hlp]# ls
yangweihao

 

不做讲述了....