Re: PATCH: new "void" memory region attribute

[Andrew Cagney <ac131313@cygnus.com>]

> Andrew Cagney wrote:
> 
>> 
> 
>> > enum mem_access_mode
>> > {
>> > -  MEM_RW,                    /* read/write */
>> > -  MEM_RO,                    /* read only */
>> > -  MEM_WO                     /* write only */
>> > +  MEM_VOID = 0,
>> > +  MEM_READ = 1,
>> > +  MEM_WRITE = 2,
>> > +  MEM_RW = MEM_READ | MEM_WRITE,
>> > };
>> >
> 
>> 
>> Greg, I'm just wondering why this part change?  Wouldn't just adding a
>> MEM_VOID entry have been easier?
> 
> 
> No, it's because (attr != MEM_RO) is no longer a sufficient test
> to see if a section is writeable.  There are now two modes that are
> not writeable -- MEM_RO and MEM_VOID.  He could have made the tests
> more complex, he simply chose to do it this way instead.

Ah, ok.  I see why I'm confused.  The command set is an enumeration:

	void ro ro rw

but the internal representation is now:

	r, w

Greg, might as well go the whole hog, make it a set: rwx (don't wan't a 
programmer trying to jump into a device :-)

Otherwize ok.

Andrew