با سلام خدمت دوستان محترم
من یه ماژول کرنل نوشتم که مختصات موس را می خواند و درون فایل ourmouse واقع در پوشه dev مینویسد. اما بعد از نصب ماژول و mknod کردن فایل ourmouse با ماینر 0 و ماژر 60، زمانی که آن را cat میکنم خطای invalid argument می دهد. کدم هم به شکل زیر است:
static int mouse_users = 0; /* User count */
static int mouse_dx = 0; /* Position changes */
static int mouse_dy = 0;
static int mouse_event = 0; /* Mouse has moved */
static unsigned char mouse_buttons = 0;
#define MOD_INC_USE_COUNT;
#define MOD_DEC_USE_COUNT;
#define OURMOUSE_BASE 0x300
static int mouse_intr = 5;
static struct wait_queue *mouse_wait;
static DEFINE_SPINLOCK(mouse_lock);
static void ourmouse_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
printk(KERN_INFO "interrupt");
char delta_x;
char delta_y;
unsigned char new_buttons;
delta_x = inb(OURMOUSE_BASE);
delta_y = inb(OURMOUSE_BASE+1);
new_buttons = inb(OURMOUSE_BASE+2);
if(delta_x || delta_y || new_buttons != mouse_buttons)
{
/* Something happened */
spin_lock(&mouse_lock);
mouse_event = 1;
mouse_dx += delta_x;
mouse_dy += delta_y;
mouse_buttons = new_buttons;
spin_unlock(&mouse_lock);
wake_up_interruptible(&mouse_wait);
}
}
static int open_mouse(struct inode *inode, struct file *file)
{
printk(KERN_INFO "open");
if(mouse_users++)
return 0;
MOD_INC_USE_COUNT;
if(request_irq(mouse_intr, ourmouse_interrupt, 0, "ourmouse", NULL))
{
mouse_users--;
MOD_DEC_USE_COUNT;
return -EBUSY;
}
mouse_dx = 0;
mouse_dy = 0;
mouse_event = 0;
mouse_buttons = 0;
return 0;
}
static int close_mouse(struct inode *inode, struct file *file)
{
printk(KERN_INFO "close");
if(--mouse_users)
return 0;
free_irq(ourmouse_interrupt, NULL);
MOD_DEC_USE_COUNT;
return 0;
}
static ssize_t write_mouse(struct file *file, const char *buffer, size_t
count, loff_t *ppos)
{
printk(KERN_INFO "write");
return -EINVAL;
}
static unsigned int mouse_poll(struct file *file, poll_table *wait)
{
printk(KERN_INFO "poll");
poll_wait(file, &mouse_wait, wait);
if(mouse_event)
return POLLIN | POLLRDNORM;
return 0;
}
static ssize_t mouse_read(struct file *file, char *buffer,
size_t count, loff_t *pos)
{
printk(KERN_INFO "read");
int dx, dy;
unsigned char button;
unsigned long flags;
int n;
if(count<3)
return -EINVAL;
/*
* Wait for an event
*/
while(!mouse_event)
{
if(file->f_flags&O_NDELAY)
return -EAGAIN;
interruptible_sleep_on(&mouse_wait);
if(signal_pending(current))
return -ERESTARTSYS;
}
/* Grab the event */
spin_lock_irqsave(&mouse_lock, flags);
dx = mouse_dx;
dy = mouse_dy;
button = mouse_buttons;
if(dx<=-127)
dx=-127;
if(dx>=127)
dx=127;
if(dy<=-127)
dy=-127;
if(dy>=127)
dy=127;
mouse_dx -= dx;
mouse_dy -= dy;
if(mouse_dx == 0 && mouse_dy == 0)
mouse_event = 0;
spin_unlock_irqrestore(&mouse_lock, flags);
if(put_user(button|0x80, buffer))
return -EFAULT;
if(put_user((char)dx, buffer+1))
return -EFAULT;
if(put_user((char)dy, buffer+2))
return -EFAULT;
for(n=3; n < count; n++)
if(put_user(0x00, buffer+n))
return -EFAULT;
return count;
}
struct file_operations our_mouse_fops = {
NULL, /* Mice don't seek */
mouse_read, /* You can read a mouse */
write_mouse, /* This won't do a lot */
NULL, /* No readdir - not a directory */
mouse_poll, /* Poll */
NULL, /* No ioctl calls */
NULL, /* No mmap */
open_mouse, /* Called on open */
NULL, /* Flush - 2.2+ only */
close_mouse, /* Called on close */
};
static struct miscdevice our_mouse = {
1, "ourmouse", &our_mouse_fops
};
__init ourmouse_init(void)
{
if(check_region(OURMOUSE_BASE, 3)){
printk(KERN_INFO "no check_region");
return -ENODEV;
}
request_region(OURMOUSE_BASE, 3, "ourmouse");
misc_register(&our_mouse);
return 0;
}
#ifdef MODULE
int init_module(void)
{
if(ourmouse_init()<0){
return -ENODEV;
}
return 0;
}
void cleanup_module(void)
{
misc_deregister(&our_mouse);
release_region(OURMOUSE_BASE, 3);
}
#endif
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