How to pass parameters to Linux system call?

Question

I\'m a college student studying OS.

I\'m trying to add my own system call in Linux kernel, and something is going wrong.

My environment is stated below:

Answer 1

I found the solution. As @Ajay Brahmakshatriya answered, I should use SYSCALL_DEFINEx macro. And also, I should modify arch/x86/entry/syscalls/syscall_64.tbl as well.

Here's final summary.

How to add new system calls

First, modify arch/x86/entry/syscalls/syscall_64.tbl : add those lines below.

335     common     my_syscall_0     __x64_sys_my_syscall_0
336     common     my_syscall_1     __x64_sys_my_syscall_1
337     common     my_syscall_2     __x64_sys_my_syscall_2

Second, modify include/linux/syscalls.h : add those lines below.

asmlinkage long sys_my_syscall_0(void);
asmlinkage long sys_my_syscall_1(int);
asmlinkage long sys_my_syscall_2(int, int);

Third, create a new file for implementation. For my case, kernel/my_syscall.c.

#include 
#include 

SYSCALL_DEFINE0(my_syscall_0)
{
    printk("my_syscall_0\n");
    return 0;
}

SYSCALL_DEFINE1(my_syscall_1, int, a)
{
    printk("my_syscall_1 : %d\n", a);
    return 0;
}

SYSCALL_DEFINE2(my_syscall_2, int, a, int, b)
{
    printk("my_syscall_2 : %d, %d\n", a, b);
    return b;
}

Fourth, add created file to Makefile in its directory. For my case, kernel/Makefile.

...
obj-y = fork.o exec_domain.o panic.o \
        cpu.o exit.o softirq.o resource.o \
        sysctl.o sysctl_binary.o capability.o ptrace.o user.o \
        signal.o sys.o umh.o workqueue.o pid.o task_work.o \
        extable.o params.o \
        kthread.o sys_ni.o nsproxy.o \
        notifier.o ksysfs.o cred.o reboot.o \
        async.o range.o smpboot.o ucount.o \
        my_syscall.o
...

Finally, compile and install the kernel. Now, you would be able to see new system calls working well.

#include 
#include 
#include 

int main()
{
    printf("1 : %d\n", syscall(335));
    printf("2 : %d\n", syscall(336, 1));
    printf("3 : %d\n", syscall(337, 2, 3));
    return 0;
}

dmesg command shows me that system calls are working well.

# dmesg
my_syscall_0
my_syscall_1 : 1
my_syscall_2 : 2, 3