NAME
get_user - Get a simple variable from user space.
SYNOPSIS
get_user(x, ptr);
ARGUMENTS
x
Variable to store result.
ptr
Source address, in user space.
CONTEXT
User context only. This function may sleep.
DESCRIPTION
This macro copies a single simple variable from user space to kernel space. It supports simple types like char and int, but not larger data types like structures or arrays.
ptr must have pointer-to-simple-variable type, and the result of dereferencing ptr must be assignable to x without a cast.
Returns zero on success, or -EFAULT on error. On error, the variable x is set to zero.