K 10
svn:author
V 3
jhb
K 8
svn:date
V 27
2009-02-17T19:57:52.773414Z
K 7
svn:log
V 950
MFC: Rework the lifetime management of the kernel implementation of POSIX
semaphores.  Specifically, semaphores are now represented as new file
descriptor type that is set to close on exec.  This removes the need for
all of the manual process reference counting (and fork, exec, and exit
event handlers) as the normal file descriptor operations handle all of
that for us nicely.  It is also suggested as one possible implementation
in the spec and at least one other OS (OS X) uses this approach.

Refer to the original commit for more details on specific bug fixes, etc.
A notable difference in this MFC relative to the original commit to HEAD
is that the MAC entry points are unchanged to preserve the ABI for MAC
policy modules.  fstat() on a POSIX semaphore in 7 uses the
mac_check_posix_sem_getvalue() hook to determine access as that is the
closest match to stat() of the available hooks.

Discussed with:	 rwatson (MAC bits (or lack thereof))

END