On Wednesday 11 May 2016 10:04:16 Zhangjian wrote:

quoted

I don't remember. It's probably not important whether we have the shift
in there, as long as it's independent of the actual kernel page size and
user space and kernel agree on the calling conventions.

Well. I am ok with where to shift the pages size because we get the same
result. I was just thinking if we should get rid of the name of mmap2 in our
ILP32 porting. Actually, it is mmap but we name it as mmap2. User may confused
if they do not know the implementations.

That is a good point: If the implementation matches the mmap() behavior rather than
mmap2(), we should rename the macro by doing

#undef __NR_mmap2
#define __NR_mmap 222

in the uapi/asm/unistd.h file for ilp32 mode. Alternatively we can keep the
__NR_mmap2 definition but then we need to pass the pgoff (value shifted by
12 bits) argument rather than the size in bytes.

	Arnd