[klibc] sys_mmap2 on different architectures

[H. Peter Anvin]

I've looked through the code for sys_mmap2 on several architectures, and 
it looks like some architectures plays by the "shift is always 12" rule, 
  e.g. SPARC, and some expect userspace to actually obtain the page 
size, e.g. PowerPC and MIPS.  On some architectures, e.g. x86 and ARM, 
the point is moot since PAGE_SIZE is always 2^12.

a. Is this correct, or have I misunderstood the code?

b. If so, is this right, or is this a bug?  Right now both klibc and 
µClibc consider the latter a bug.

c. Which architectures are affected which way?

	-hpa