🚀 go-pugleaf

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�õ���sys_semget,sys_semctl,sys_semop

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sem.h>
#include <asm/uaccess.h>
#include <sys/syscall.h>
#define __NR_sem_init 240
#define __NR_sem_rele 241
#define __NR_sem_p    242
#define __NR_sem_v    243
extern void * sys_call_table[];
int (*original_call)(void);
asmlinkage int sys_sem_init(key_t key, int count)
{
        int semid;
        union semun arg;
        arg.val = count;
        semid = sys_semget(key, 1, IPC_CREAT|0777);
        sys_semctl(semid, 0, SETVAL, arg);
        return semid;
}
asmlinkage int sys_sem_rele(int semid)
{
        union semun arg;
        sys_semctl(semid, 0, IPC_RMID, arg);
        return 0;
}
asmlinkage int sys_sem_v(int semid, struct sembuf * psemb)
{
        struct sembuf semb;
        semb.sem_num = 0;
        semb.sem_op = 1;
        semb.sem_flg = 0;
        copy_to_user(psemb, &semb, sizeof(semb));
        return (sys_semop(semid, psemb, 1));
}
asmlinkage int sys_sem_p(int semid, struct sembuf * psemb)
{
        struct sembuf semb;
        semb.sem_num = 0;
        semb.sem_op = -1;
        semb.sem_flg = 0;
        copy_to_user(psemb, &semb, sizeof(semb));
        return (sys_semop(semid, psemb, 1));
}
int init_module()
{
        sys_call_table[__NR_sem_init] = sys_sem_init;
        sys_call_table[__NR_sem_rele] = sys_sem_rele;
        sys_call_table[__NR_sem_p] = sys_sem_p;
        sys_call_table[__NR_sem_v] = sys_sem_v;
        return 0;
}
void cleanup_module()
{
        sys_call_table[__NR_sem_init] = original_call;
        sys_call_table[__NR_sem_rele] = original_call;
        sys_call_table[__NR_sem_p] = original_call;
        sys_call_table[__NR_sem_v] = original_call;
}

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gcc -DMODULE -D__KERNEL__ -c 
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insmod��ʱ�������һ�´�����ʾ
sc.o: unresolved symbol sys_semop
sc.o: unresolved symbol sys_semctl
sc.o: unresolved symbol sys_semget

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c0179780 T sys_semget
c017a750 T sys_semop
c017a580 T sys_semctl
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