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Compile kernel driver failed when processing __user

I get a compile error when compiling a kernel driver.The error info is

Code:

pxa270_gpio_led_drv.c|27 col 70| error: expected ‘;’, ‘,’ or ‘)’ before ‘*’ token

||  static ssize_t SIMPLE_GPIO_LED_read ( struct file *file, char __user *buf, size_t count, loff_t *offset)

Part of the source file is:

Code:

static ssize_t SIMPLE_GPIO_LED_read ( struct file *file, char __user *buf, size_t count, loff_t *offset) 

{

#ifdef OURS_GPIO_LED_DEBUG 

printk ("SIMPLE_GPIO_LED_read [ --kernel--]\n"); 

#endif 

return count; 

}

The compile command is :

Code:

 gcc -c -Wall -O -D__KERNEL__ -DMODULE -I/home/test/Desktop/linux-2.4.21/include  pxa270_gpio_led_drv.c -o pxa270_gpio_led_drv.o

Can anyone help me? Thanks.

I don't recall seeing gcc print the source line with '|| ' at the beginning of the line. What version are you using?

You probably have an undefined type

You probably have an undefined type. Make sure that __user macro is properly defined.