sys_iopl  [arch/i386/kernel.c]


Changes the I/O privilege level of the current process.
This system call has to be used when you want to access the I/O ports beyond the 0x3ff range: to get the full 65536 ports bitmapped you'd need 8kB of bitmaps/process, which is a bit excessive.

Arguments

eax 110
ebx Level to change the privileges to.

Return values

If the system call succeeds the return value is 0.
If the system call fails the return value is one of the following errno values:

-EINVAL Level is greater than 3.
-EPERM The current user is not the super-user.

Remarks

Permissions are inherited by fork and exec.
The I/O privilege level for a normal process is 0.

Compatibility

n/a