sys/compat: Memset zero before copyout.

Just in case of uninitialized padding which would lead to kernel
stack disclosure. If the compiler can prove the memset redundant
then it can optimize it away; otherwise better safe than sorry.

Merge the [pgoyette-compat] branch

branches: 1.20.12; 1.20.96; 1.20.98;
Convert all the system call entry points from:
int foo(struct lwp *l, void *v, register_t *retval)
to:
int foo(struct lwp *l, const struct foo_args *uap, register_t *retval)
Fixup compat code to not write into 'uap' and (in some cases) to actually
pass a correctly formatted 'uap' structure with the right name to the
next routine.
A few 'compat' routines that just call standard ones have been deleted.
All the 'compat' code compiles (along with the kernels required to test
build it).
98% done by automated scripts.

branches: 1.19.16; 1.19.24; 1.19.28;
Kill caddr_t; there will be some MI fallout, but it will be fixed shortly.

branches: 1.18.2;
Merge newlock2 to head.

__unused removal on arguments; approved by core.

- sprinkle __unused on function decls.
- fix a couple of unused bugs
- no more -Wno-unused for i386

branches: 1.15.20; 1.15.22;
merge ktrace-lwp.

branches: 1.14.16;
Dynamic sysctl.

Gone are the old kern_sysctl(), cpu_sysctl(), hw_sysctl(),
vfs_sysctl(), etc, routines, along with sysctl_int() et al. Now all
nodes are registered with the tree, and nodes can be added (or
removed) easily, and I/O to and from the tree is handled generically.

Since the nodes are registered with the tree, the mapping from name to
number (and back again) can now be discovered, instead of having to be
hard coded. Adding new nodes to the tree is likewise much simpler --
the new infrastructure handles almost all the work for simple types,
and just about anything else can be done with a small helper function.

All existing nodes are where they were before (numerically speaking),
so all existing consumers of sysctl information should notice no
difference.

PS - I'm sorry, but there's a distinct lack of documentation at the
moment. I'm working on sysctl(3/8/9) right now, and I promise to
watch out for buses.

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22364, verified by myself.

branches: 1.12.2;
Back out the lwp/ktrace changes. They contained a lot of colateral damage,
and need to be examined and discussed more.

Pass lwp pointers throughtout the kernel, as required, so that the lwpid can
be inserted into ktrace records. The general change has been to replace
"struct proc *" with "struct lwp *" in various function prototypes, pass
the lwp through and use l_proc to get the process pointer when needed.

Bump the kernel rev up to 1.6V

Merge the nathanw_sa branch.

add RCSIDs (including regeneration of files as appropriate)

branches: 1.8.2; 1.8.4;
Sprinkle in some const.

remove include of <vm/vm.h>. <vm/vm.h> -> <uvm/uvm_extern.h>

branches: 1.6.4;
Centralise the declarations of cpu_model, machine, machine_arch,
osrelease, and ostype and remove "extern char foo[];" (for hostname
and domainname too).

Also delete redunctant decl of boottime in kern_info_43.c.

branches: 1.5.30;
fourth argument to kern_sysctl() must be a size_t *. simply passing a pointer
to SCARG(uap, len) won't do, because that'd be an int *. copy the value
into a size_t, and pass pointer to that.

kern_sysctl was missing process argument. Elimited -Wall warnings from
the files that were affected

Prefix names of system call implementation functions with `sys_'.

Make system calls conform to a standard prototype and bring those
prototypes into scope.

- Extracted all compat routines from the kern directory and moved here.
- Created compat_util.c and compat_util.h to be used by the compatibility
modules, so they don't duplicate the same code.
- Added prototypes to the stackgap allocation routines.

Merge the [pgoyette-compat] branch

branches: 1.20.12; 1.20.96;
Convert all the system call entry points from:
int foo(struct lwp *l, void *v, register_t *retval)
to:
int foo(struct lwp *l, const struct foo_args *uap, register_t *retval)
Fixup compat code to not write into 'uap' and (in some cases) to actually
pass a correctly formatted 'uap' structure with the right name to the
next routine.
A few 'compat' routines that just call standard ones have been deleted.
All the 'compat' code compiles (along with the kernels required to test
build it).
98% done by automated scripts.

branches: 1.19.16; 1.19.24; 1.19.28;
Kill caddr_t; there will be some MI fallout, but it will be fixed shortly.

branches: 1.18.2;
Merge newlock2 to head.

__unused removal on arguments; approved by core.

- sprinkle __unused on function decls.
- fix a couple of unused bugs
- no more -Wno-unused for i386

branches: 1.15.20; 1.15.22;
merge ktrace-lwp.

branches: 1.14.16;
Dynamic sysctl.

Gone are the old kern_sysctl(), cpu_sysctl(), hw_sysctl(),
vfs_sysctl(), etc, routines, along with sysctl_int() et al. Now all
nodes are registered with the tree, and nodes can be added (or
removed) easily, and I/O to and from the tree is handled generically.

Since the nodes are registered with the tree, the mapping from name to
number (and back again) can now be discovered, instead of having to be
hard coded. Adding new nodes to the tree is likewise much simpler --
the new infrastructure handles almost all the work for simple types,
and just about anything else can be done with a small helper function.

All existing nodes are where they were before (numerically speaking),
so all existing consumers of sysctl information should notice no
difference.

PS - I'm sorry, but there's a distinct lack of documentation at the
moment. I'm working on sysctl(3/8/9) right now, and I promise to
watch out for buses.

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22364, verified by myself.

branches: 1.12.2;
Back out the lwp/ktrace changes. They contained a lot of colateral damage,
and need to be examined and discussed more.

Pass lwp pointers throughtout the kernel, as required, so that the lwpid can
be inserted into ktrace records. The general change has been to replace
"struct proc *" with "struct lwp *" in various function prototypes, pass
the lwp through and use l_proc to get the process pointer when needed.

Bump the kernel rev up to 1.6V

Merge the nathanw_sa branch.

add RCSIDs (including regeneration of files as appropriate)

branches: 1.8.2; 1.8.4;
Sprinkle in some const.

remove include of <vm/vm.h>. <vm/vm.h> -> <uvm/uvm_extern.h>

branches: 1.6.4;
Centralise the declarations of cpu_model, machine, machine_arch,
osrelease, and ostype and remove "extern char foo[];" (for hostname
and domainname too).

Also delete redunctant decl of boottime in kern_info_43.c.

branches: 1.5.30;
fourth argument to kern_sysctl() must be a size_t *. simply passing a pointer
to SCARG(uap, len) won't do, because that'd be an int *. copy the value
into a size_t, and pass pointer to that.

kern_sysctl was missing process argument. Elimited -Wall warnings from
the files that were affected

Prefix names of system call implementation functions with `sys_'.

Make system calls conform to a standard prototype and bring those
prototypes into scope.

- Extracted all compat routines from the kern directory and moved here.
- Created compat_util.c and compat_util.h to be used by the compatibility
modules, so they don't duplicate the same code.
- Added prototypes to the stackgap allocation routines.