Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Define two new sysctl node flags: CTLFLAG_CAPRD and CTLFLAG_CAPRW, which
may be jointly referenced via the mask CTLFLAG_CAPRW. Sysctls with these
flags are available in Capsicum's capability mode; other sysctl nodes are
not.

Flag several useful sysctls as available in capability mode, such as memory
layout sysctls required by the run-time linker and malloc(3). Also expose
access to randomness and available kernel features.

A few sysctls are enabled to support name->MIB conversion; these may leak
information to capability mode by virtue of providing resolution on names
not flagged for access in capability mode. This is, generally, not a huge
problem, but might be something to resolve in the future. Flag these cases
with XXX comments.

Submitted by: jonathan
Sponsored by: Google, Inc.

Set various POSIX capability sysctls to the version of the API that is
supported rather than 1. They are supposed to return a suitable value
for sysconf(3). While here, make the fsync sysctl match <unistd.h>.

MFC after: 1 week

Add a facility to dynamically adjust or unconfigure p1003_1b mib.
Use it to allow to tune sem_nsem_max at runtime, only when sem.ko
module is present in kernel.

Requested and tested by: amdmi3
Reviewed by: jhb
MFC after: 3 days

Fix mispatch of includes list; allows my kernel to build successfully.

Update #includes list.

Forced commit to note that these files have been repo-copied from
src/sys/posix4/.

Repo-copy done by: kuriyama

Back when VOP_* was introduced, we did not have new-style struct
initializations but we did have lofty goals and big ideals.

Adjust to more contemporary circumstances and gain type checking.

Replace the entire vop_t frobbing thing with properly typed
structures. The only casualty is that we can not add a new
VOP_ method with a loadable module. History has not given
us reason to belive this would ever be feasible in the the
first place.

Eliminate in toto VOCALL(), vop_t, VNODEOP_SET() etc.

Give coda correct prototypes and function definitions for
all vop_()s.

Generate a bit more data from the vnode_if.src file: a
struct vop_vector and protype typedefs for all vop methods.

Add a new vop_bypass() and make vop_default be a pointer
to another struct vop_vector.

Remove a lot of vfs_init since vop_vector is ready to use
from the compiler.

Cast various vop_mumble() to void * with uppercase name,
for instance VOP_PANIC, VOP_NULL etc.

Implement VCALL() by making vdesc_offset the offsetof() the
relevant function pointer in vop_vector. This is disgusting
but since the code is generated by a script comparatively
safe. The alternative for nullfs etc. would be much worse.

Fix up all vnode method vectors to remove casts so they
become typesafe. (The bulk of this is generated by scripts)

Use __FBSDID().

Rework the sysconf(3) interaction with aio:

sysconf.c:
Use 'break' rather than 'goto yesno' in sysconf.c so that we report a '0'
return value from the kernel sysctl.

vfs_aio.c:
Make aio reset its configuration parameters to -1 after unloading
instead of 0.

posix4_mib.c:
Initialize the aio configuration parameters to -1
to indicate that it is not loaded.
Add a facility (p31b_iscfg()) to determine if a posix4 facility has been
initialized to avoid having to re-order the SYSINITs.
Use p31b_iscfg() to determine if aio has had a chance to run yet which
is likely if it is compiled into the kernel and avoid spamming its
values.
Introduce a macro P31B_VALID() instead of doing the same comparison over
and over.

posix4.h:
Prototype p31b_iscfg().

Change the way support for asynchronous I/O is indicated to applications
to conform to 1003.1-2001. Make it possible for applications to actually
tell whether or not asynchronous I/O is supported.

Since FreeBSD's aio implementation works on all descriptor types, don't
call down into file or vnode ops when [f]pathconf() is asked about
_PC_ASYNC_IO; this avoids the need for every file and vnode op to know about
it.

Add the rest of the kernel support for the sem_ API in kern/uipc_sem.c.

Option 'P1003_1B_SEMAPHORES' to compile them in, or load the "sem" module
to activate them.

Have kern/makesyscalls.sh emit an include for sys/_semaphore.h into sysproto.h
to pull in the typedef for semid_t.

Add the syscalls to the syscall table as module stubs.

Add $FreeBSD$.
Initialize the POSIX.1b sysconf information appropriately for
non-optional kernel functions.

* Change sysctl from using linker_set to construct its tree using SLISTs.
This makes it possible to change the sysctl tree at runtime.

* Change KLD to find and register any sysctl nodes contained in the loaded
file and to unregister them when the file is unloaded.

Reviewed by: Archie Cobbs <archie@whistle.com>,
Peter Wemm <peter@netplex.com.au> (well they looked at it anyway)

Finish _POSIX_PRIORITY_SCHEDULING. Needs P1003_1B and
_KPOSIX_PRIORITY_SCHEDULING options to work. Changes:

Change all "posix4" to "p1003_1b". Misnamed files are left
as "posix4" until I'm told if I can simply delete them and add
new ones;

Add _POSIX_PRIORITY_SCHEDULING system calls for FreeBSD and Linux;

Add man pages for _POSIX_PRIORITY_SCHEDULING system calls;

Add options to LINT;

Minor fixes to P1003_1B code during testing.

Reviewed by: msmith, bde long ago
POSIX.4 headers and sysctl variables. Nothing should change
unless POSIX4 is defined or _POSIX_VERSION is set to 199309.