The following patches introduce per user rlimits for both queued signals and
POSIX message queues.  The changes touch all the arches resource.h files as
well as init_task.c to get the rlimit defaults setup.

Both require caching the user_struct to avoid problems with setuid().

The signal changes makes some small changes to send_signal() to pass along the
task being signalled to get proper accounting for signals initiated in
interrupt.  Thanks to Marcelo for getting this one going.


This patch:

Add an rlimit entry to control the maximum number of pending signals a user
may have.  This is essentially just the resource.h changes.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>