I found 2 bugs in my previous single copy pipe version:

* Could deadlock on the mmap_semaphore with multithreaded apps.
* It doesn't follow the atomicity requirements with blocking transfers
if a signal arrives. SuS isn't 100% clear, but FreeBSD and Tru64
guarantee it.

I've uploaded the new patches to
http://www.colorfullife.com/~manfred/linux-2.5/kiopipe/

* patch-pgw: enum_user_pages - helper function for getting 'struct
page*' from virtual addresses, and use it for access_process_vm and
map_user_kiobuf.
	net 62 lines removed ;-)
* patch-kiopipe: actual single copy pipe, not tuned. based on patch-pgw.
* patch-expand: unrelated.

Unfortunately kiopipe is visible to broken user space aps.
(run test5.cpp - it stalls with kiopipe, but finishes on all other Unix
versions I tested)

patch-pgw is attached - it simplifies access_process_vm and
map_user_kiobuf.
I'd apreciate any comments.

--
	Manfred