PHYS (2)
allow a process to access physical addresses [NOT IMPLEMENTED]
SYNOPSIS
int phys(int physnum , char * virtaddr , long size ,
char * physaddr );
b
DESCRIPTION
WARNING :
Since this function is not implemented as of Linux 0.99.11, it will always
return -1 and set
errno
to
ENOSYS .
phys maps arbitrary physical memory into a process's virtual
address space. physnum is number (0\(en3) that specifies which
of the 4 physical spaces to set up. Up to 4 phys calls can be
active at any one time. virtaddr is the process's virtual address.
size is the number of bytes to map in. physaddr is the
physical address to map in.
Valid virtaddr and physaddr values are constrained by
hardware and must be at an address multiple of the resolution of the
CPU's memory management scheme. If size is non zero, size
is rounded up to the next MMU resolution boundary. If size is
zero, any previous phys(2) mapping for that physnum is
nullified.
RETURN VALUE
On success, zero is returned. On error, -1 is returned, and
errno
is set appropriately.
CONFORMING TO
BUGS
phys is very machine dependent.
SEE ALSO
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