CVS log for src/sys/arch/sparc64/sparc64/vm_machdep.c

Up to [cvs.NetBSD.org] / src / sys / arch / sparc64 / sparc64

Request diff between arbitrary revisions

Keyword substitution: kv
Default branch: MAIN

Sync with HEAD

retry timed out IPIs, complain and dump timing info into dmesg
ok martin@

update from HEAD

Sync with HEAD (as of 26th Dec)

Pull up following revision(s) (requested by martin in ticket #1028):
	sys/arch/sparc64/sparc64/locore.s: revision 1.386
	sys/arch/sparc64/sparc64/vm_machdep.c: revision 1.101
	sys/arch/sparc64/sparc64/netbsd32_machdep.c: revision 1.105
	sys/arch/sparc64/sparc64/netbsd32_machdep.c: revision 1.106
- Basically revert r1.246 of locore.s and r1.73 of vm_machdep.c:
	Remove special case handling for userland lwps from cpu_lwp_fork,
	instead do it in lwp_trampoline when we first return to userland.
  which was a stupid idea - since we did now set all fork child's %tstate
  (and thus %pstate when back in userland) to the current kernel's userland
  default. This meant we lost the address mask bit for 32bit processes and
  all memory model details for 64bit ones.
  Move it back to cpu_lwp_fork and fix the condition to only do it once when
  forking init.
- Fix kmem_free() size mismatch
- Convert siginfo to 32bit version before copying it out to 32bit userland.

Pull up following revision(s) (requested by martin in ticket #1028):
	sys/arch/sparc64/sparc64/locore.s: revision 1.386
	sys/arch/sparc64/sparc64/vm_machdep.c: revision 1.101
	sys/arch/sparc64/sparc64/netbsd32_machdep.c: revision 1.105
	sys/arch/sparc64/sparc64/netbsd32_machdep.c: revision 1.106
- Basically revert r1.246 of locore.s and r1.73 of vm_machdep.c:
	Remove special case handling for userland lwps from cpu_lwp_fork,
	instead do it in lwp_trampoline when we first return to userland.
  which was a stupid idea - since we did now set all fork child's %tstate
  (and thus %pstate when back in userland) to the current kernel's userland
  default. This meant we lost the address mask bit for 32bit processes and
  all memory model details for 64bit ones.
  Move it back to cpu_lwp_fork and fix the condition to only do it once when
  forking init.
- Fix kmem_free() size mismatch
- Convert siginfo to 32bit version before copying it out to 32bit userland.

Pull up following revision(s) (requested by martin in ticket #1343):
	sys/arch/sparc64/sparc64/locore.s: revision 1.386
	sys/arch/sparc64/sparc64/vm_machdep.c: revision 1.101
	sys/arch/sparc64/sparc64/netbsd32_machdep.c: revision 1.105
	sys/arch/sparc64/sparc64/netbsd32_machdep.c: revision 1.106
Basically revert r1.246 of locore.s and r1.73 of vm_machdep.c:
	Remove special case handling for userland lwps from cpu_lwp_fork,
	instead do it in lwp_trampoline when we first return to userland.
which was a stupid idea - since we did now set all fork child's %tstate
(and thus %pstate when back in userland) to the current kernel's userland
default. This meant we lost the address mask bit for 32bit processes and
all memory model details for 64bit ones.
Move it back to cpu_lwp_fork and fix the condition to only do it once when
forking init.
Fix kmem_free() size mismatch
Convert siginfo to 32bit version before copying it out to 32bit userland.

Pull up following revision(s) (requested by martin in ticket #1343):
	sys/arch/sparc64/sparc64/locore.s: revision 1.386
	sys/arch/sparc64/sparc64/vm_machdep.c: revision 1.101
	sys/arch/sparc64/sparc64/netbsd32_machdep.c: revision 1.105
	sys/arch/sparc64/sparc64/netbsd32_machdep.c: revision 1.106
Basically revert r1.246 of locore.s and r1.73 of vm_machdep.c:
	Remove special case handling for userland lwps from cpu_lwp_fork,
	instead do it in lwp_trampoline when we first return to userland.
which was a stupid idea - since we did now set all fork child's %tstate
(and thus %pstate when back in userland) to the current kernel's userland
default. This meant we lost the address mask bit for 32bit processes and
all memory model details for 64bit ones.
Move it back to cpu_lwp_fork and fix the condition to only do it once when
forking init.
Fix kmem_free() size mismatch
Convert siginfo to 32bit version before copying it out to 32bit userland.

Pull up following revision(s) (requested by martin in ticket #1343):
	sys/arch/sparc64/sparc64/locore.s: revision 1.386
	sys/arch/sparc64/sparc64/vm_machdep.c: revision 1.101
	sys/arch/sparc64/sparc64/netbsd32_machdep.c: revision 1.105
	sys/arch/sparc64/sparc64/netbsd32_machdep.c: revision 1.106
Basically revert r1.246 of locore.s and r1.73 of vm_machdep.c:
	Remove special case handling for userland lwps from cpu_lwp_fork,
	instead do it in lwp_trampoline when we first return to userland.
which was a stupid idea - since we did now set all fork child's %tstate
(and thus %pstate when back in userland) to the current kernel's userland
default. This meant we lost the address mask bit for 32bit processes and
all memory model details for 64bit ones.
Move it back to cpu_lwp_fork and fix the condition to only do it once when
forking init.
Fix kmem_free() size mismatch
Convert siginfo to 32bit version before copying it out to 32bit userland.

Basically revert r1.246 of locore.s and r1.73 of vm_machdep.c:

	Remove special case handling for userland lwps from cpu_lwp_fork,
	instead do it in lwp_trampoline when we first return to userland.

which was a stupid idea - since we did now set all fork child's %tstate
(and thus %pstate when back in userland) to the current kernel's userland
default. This meant we lost the address mask bit for 32bit processes and
all memory model details for 64bit ones.

Move it back to cpu_lwp_fork and fix the condition to only do it once when
forking init.

Rebase to HEAD as of a few days ago.

sync with head.

for a reference, the tree before this commit was tagged
as yamt-pagecache-tag8.

this commit was splitted into small chunks to avoid
a limitation of cvs.  ("Protocol error: too many arguments")

sync with head

Remove unused variable

sync with head

sync to -current.

Remove COMPAT_SA / KERN_SA.  Welcome to 6.99.3!
Approved by core@.

Fix namespace confilicts membar_ops(3) vs. macros for SPARC V9
membar instructions.

#include <sys/bus.h> instead of <machine/bus.h>.

Sync with HEAD.

sync with head

Sync with HEAD

Allow storing and receiving the LWP private pointer via ucontext_t
on all platforms except VAX and IA64. Add fast access via register for
AMD64, i386 and SH3 ports. Use this fast access in libpthread to replace
the stack based pthread_self(). Implement skeleton support for Alpha,
HPPA, PowerPC, SPARC and SPARC64, but leave it disabled.

Ports that support this feature provide __HAVE____LWP_GETPRIVATE_FAST in
machine/types.h and a corresponding __lwp_getprivate_fast in
machine/mcontext.h.

This material is based upon work partially supported by
The NetBSD Foundation under a contract with Joerg Sonnenberger.

Sync with HEAD

Make vmapbuf() return success/error and make physio deal with a
failure.

Copy PK_32 to p2->p_flag instead of doing it in the cpu_proc_fork hook.

Retire struct user, remove sys/user.h inclusions.  Note sys/user.h header
as obsolete.  Remove USER_TO_UAREA/UAREA_TO_USER macros.

Various #include fixes and review by matt@.

Sync with HEAD.

remove an XXX comment.

sync to netbsd-5

sync with head

Use lwp_getpcb() on sparc{64} and sun2/3 MD code, clean from struct user usage.

Add a flags argument to pmap_kenter_pa(9).
Patch showed on tech-kern@ http://mail-index.netbsd.org/tech-kern/2009/11/04/msg006434.html
No objections.

sync with head

Pull up following revision(s) (requested by martin in ticket #786):
	sys/arch/sparc64/include/cpu.h: revision 1.86
	sys/arch/sparc64/sparc64/locore.s: revision 1.291
	sys/arch/sparc64/sparc64/vm_machdep.c: revision 1.89
cpu_setfunc() can not use lwp_trampoline, as that has additional lwp startup
semantics. Use a simpler setfunc_trampoline instead.

Pull up following revision(s) (requested by martin in ticket #786):
	sys/arch/sparc64/include/cpu.h: revision 1.86
	sys/arch/sparc64/sparc64/locore.s: revision 1.291
	sys/arch/sparc64/sparc64/vm_machdep.c: revision 1.89
cpu_setfunc() can not use lwp_trampoline, as that has additional lwp startup
semantics. Use a simpler setfunc_trampoline instead.

cpu_setfunc() can not use lwp_trampoline, as that has additional lwp startup
semantics. Use a simpler setfunc_trampoline instead.

Pull up following revision(s) (requested by martin in ticket #774):
	sys/arch/sparc64/sparc64/vm_machdep.c: revision 1.88
Deja Vu: when preparing the initial trap frame for a new forked lwp,
explicitly clear condition code. Otherwise we might catch a signal
(handlers are inherited from the parent) before we ever return to
userland. The current trapframe is converted into a ucontext and after
the signal handler returns, the lwp stays in userland and directly
uses the ucontext to return to the fork call.
Fixes PR 41302.

Pull up following revision(s) (requested by martin in ticket #774):
	sys/arch/sparc64/sparc64/vm_machdep.c: revision 1.88
Deja Vu: when preparing the initial trap frame for a new forked lwp,
explicitly clear condition code. Otherwise we might catch a signal
(handlers are inherited from the parent) before we ever return to
userland. The current trapframe is converted into a ucontext and after
the signal handler returns, the lwp stays in userland and directly
uses the ucontext to return to the fork call.
Fixes PR 41302.

Deja Vu: when preparing the initial trap frame for a new forked lwp,
explicitly clear condition code. Otherwise we might catch a signal
(handlers are inherited from the parent) before we ever return to
userland. The current trapframe is converted into a ucontext and after
the signal handler returns, the lwp stays in userland and directly
uses the ucontext to return to the fork call.
Fixes PR 41302.

Sync with HEAD.

Commit is split, to avoid a "too many arguments" protocol error.

sync with head.

Sync with HEAD.

ANSIfy functions with function-pointer arguments

Change about 4500 of the K&R function definitions to ANSI ones.
There are still about 1600 left, but they have ',' or /* ... */
in the actual variable definitions - which my awk script doesn't handle.
There are also many that need () -> (void).
(The script does handle misordered arguments.)

Sync with HEAD.

Sync with HEAD.

Update haad-dm branch to haad-dm-base2.

Make the emulations, exec formats, coredump, NFS, and the NFS server
into modules. By and large this commit:

- shuffles header files and ifdefs
- splits code out where necessary to be modular
- adds module glue for each of the components
- adds/replaces hooks for things that can be installed at runtime

Avoid code duplication: make cpu_lwp_fork() use cpu_setfunc(). Leave
the inlinig to the compiler. Suggested by Nick Hudson.

Sync with HEAD.

resurrect cpu_setfunc(), adapted to new world order.

Remove unnecessary includes.

Sync with HEAD.

Sync with wrstuden-revivesa-base-2.

Sync with head.

Switch fpstate buffer allocation from malloc to pool_cache.

Ok by martin@.

Sync with HEAD.

sync with head.

sync with head.

sync with HEAD

Fix a race condition in IPI handlers of save/drop fpstate, from OpenBSD.
Reported and tested by martin@.

sync with head.

Improve FPU state save/clear like x86, idea from OpenBSD.

sync with head.

Get rid of the IPI simple_lock.

sync with HEAD

sync with head.

Merge the ppcoea-renovation branch to HEAD.

This branch was a major cleanup and rototill of many of the various OEA
cpu based PPC ports that focused on sharing as much code as possible
between the various ports to eliminate near-identical copies of files in
every tree.  Additionally there is a new PIC system that unifies the
interface to interrupt code for all different OEA ppc arches.  The work
for this branch was done by a variety of people, too long to list here.

TODO:
bebox still needs work to complete the transition to -renovation.
ofppc still needs a bunch of work, which I will be looking at.
ev64260 still needs to be renovated
amigappc was not attempted.

NOTES:
pmppc was removed as an arch, and moved to a evbppc target.

Sync with head.

Sync with HEAD

Sync with HEAD.

Cleanup cpu_info: get rid of ci_number and ci_upaid, use ci_index
and ci_cpuid instead.

sync with head.

Sync with HEAD.

Sync with HEAD.

Sync with HEAD.

Correct some comments (proc -> lwp conversion)

Sync with head.

Sync with HEAD.

Sync with head.

fix some NOTDEF_DEBUG code.

Sync with head.

Update to HEAD.

Remove special case handling for userland lwps from cpu_lwp_fork, instead
do it in lwp_trampoline when we first return to userland.

No need to pass "old lwp" to lwp_trampoline - we'll get it as return
value from cpu_swithchto() once the lwp gets scheduled for the first
time.

merge yamt-idlelwp branch.  asked by core@.  some ports still needs work.

from doc/BRANCHES:

	idle lwp, and some changes depending on it.

	1. separate context switching and thread scheduling.
	   (cf. gmcgarry_ctxsw)
	2. implement idle lwp.
	3. clean up related MD/MI interfaces.
	4. make scheduler(s) modular.

port yamt-idlelwp to sparc64.  this does not work yet, but others
have asked that i commit this work-in-progress.

currently it gets a double fault during a window save operation
and crashes to the prom.  (it seems very much like the problem
that i see on SMP sparc64, but there is no real evidence it is
the same root cause.)

Sync with HEAD.

Kill caddr_t; there will be some MI fallout, but it will be fixed shortly.

- sync with head.
- move sched_changepri back to kern_synch.c as it doesn't know PPQ anymore.

sync with head.

Change the process/lwp flags seen by userland via sysctl back to the
P_*/L_* naming convention, and rename the in-kernel flags to avoid
conflict. (P_ -> PK_, L_ -> LW_ ). Add back the (now unused) LSDEAD
constant.

Restores source compatibility with pre-newlock2 tools like ps or top.

Reviewed by Andrew Doran.

Merge newlock2 to head.

Checkpoint work in progress.

sync with head.

Sync with head.

sync with head

remove an always printed debugging message.

file vm_machdep.c was added on branch yamt-splraiseipl on 2006-10-22 06:05:12 +0000

Lazy FPU handling for the MULTIPROCESSOR case

Do not bother to save fpu state when we are about to get rid of it.

sync with head

sync with head.

Make cpu_coredump dependent on COREDUMP

sync with head.

Sync with head.

sync with head.

ANSIfication: u_intN_t -> uintN_t, use ANSI function declarations/definitions
instead of K&R ones.

merge ktrace-lwp.

Sync with HEAD. Here we go again...

sync with head.

Follow the lead of the sparc port:
 - move md_flags back to mdproc, because we only have per-proc flags
   currently
 - implement cpu_proc_fork() to init p_md.md_flags on fork

Fix typo in last.  This compiles once again.

Rework the coredump code to have no explicit knownledge of how coredump
i/o is done.  Instead, pass an opaque cookie which is then passed to a
new routine, coredump_write, which does the actual i/o.  This allows the
method of doing i/o to change without affecting any future MD code.
Also, make netbsd32_core.c [re]use core_netbsd.c (in a similar manner that
core_elf64.c uses core_elf32.c) and eliminate that code duplication.
cpu_coredump{,32} is now called twice, first with a NULL iocookie to fill
the core structure and a second to actually write md parts of the coredump.
All i/o is nolonger random access and is suitable for shipping over a stream.

sync with -current

Sync with HEAD.

merge yamt-km branch.
- don't use managed mappings/backing objects for wired memory allocations.
  save some resources like pv_entry.  also fix (most of) PR/27030.
- simplify kernel memory management API.
- simplify pmap bootstrap of some ports.
- some related cleanups.

convert arch/sparc64 to new apis.

Fix the sync with head I botched.

Sync with HEAD.

There's no need to pass a proc value when using UIO_SYSSPACE with
vn_rdwr(9) and uiomove(9).

OK'd by Jason Thorpe

Sync with HEAD

Garbage-collect pagemove(); nothing use it anymore (YAY!!!)

Adapt to branch.

sparc64 GENERIC compiles.

Sync with HEAD

Rename switchexit to cpu_exit and g/c the old C implementation of cpu_exit.

Don't rely on proc_trampoline to clear condition codes for a new
child process on fork - it could be overtaken by a signal delivery
and then use the stale condition code in the trap frame.
Instead, set tf_tstate aproprietaly right from the start.
Fixes PR sparc64/20675.
Many thanks to Paul Kranenburg for hints on a similar problem he fixed
for the sparc port.

Rearrange process exit path to avoid need to free resources from different
process context ('reaper').

From within the exiting process context:
* deactivate pmap and free vmspace while we can still block
* introduce MD cpu_lwp_free() - this cleans all MD-specific context (such
  as FPU state), and is the last potentially blocking operation;
  all of cpu_wait(), and most of cpu_exit(), is now folded into cpu_lwp_free()
* process is now immediatelly marked as zombie and made available for pickup
  by parent; the remaining last lwp continues the exit as fully detached
* MI (rather than MD) code bumps uvmexp.swtch, cpu_exit() is now same
  for both 'process' and 'lwp' exit

uvm_lwp_exit() is modified to never block; the u-area memory is now
always just linked to the list of available u-areas. Introduce (blocking)
uvm_uarea_drain(), which is called to release the excessive u-area memory;
this is called by parent within wait4(), or by pagedaemon on memory shortage.
uvm_uarea_free() is now private function within uvm_glue.c.

MD process/lwp exit code now always calls lwp_exit2() immediatelly after
switching away from the exiting lwp.

g/c now unneeded routines and variables, including the reaper kernel thread

Minor cleanup: remove unused code, sync a comment with current reality.

bzero/bcopy -> memset/memcpy

__KERNEL_RCSID()

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

struct proc * -> struct lwp *

Merge the nathanw_sa branch.

Catch up to -current.

sync kqueue with -current; this includes merge of gehenna-devsw branch,
merge of i386 MP branch, and part of autoconf rototil work

Don't include <sys/map.h>.

many improvements:
 - use struct vm_page_md for attaching pv entries to struct vm_page
 - change pseg_set()'s return value to indicate whether the spare page
   was used as an L2 or L3 PTP.
 - use a pool for pv entries instead of malloc().
 - put PTPs on a list attached to the pmap so we can free them
   more efficiently (by just walking the list) in pmap_destroy().
 - use the new pmap_remove_all() interface to avoid flushing the cache and TLB
   for each pmap_remove() that's done as we are tearing down an address space.
 - in pmap_enter(), handle replacing an existing mapping more efficiently
   than just calling pmap_remove() on it.  also, skip flushing the
   TSB and TLB if there was no previous mapping, since there can't be
   anything we need to flush.  also, preload the TSB if we're pre-setting
   the mod/ref bits.
 - allocate hardware contexts like the MIPS pmap:
   allocate them all sequentially without reuse, then once we run out
   just invalidate all user TLB entries and flush the entire L1 dcache.
 - fix pmap_extract() for the case where the va is not page-aligned and
   nothing is mapped there.
 - fix calculation of TSB size.  it was comparing physmem (which is
   in units of pages) to constants that only make sense if they are
   in units of bytes.
 - avoid sleeping in pmap_enter(), instead let the caller do it.
 - use pmap_kenter_pa() instead of pmap_enter() where appropriate.
 - remove code to handle impossible cases in various functions.
 - tweak asm code to pipeline a little better.
 - remove many unnecessary spls and membars.
 - lots of code cleanup.
 - no doubt other stuff that I've forgotten.

the result of all this is that a fork+exit microbenchmark is 34% faster
and a fork+exec+exit microbenchmark is 28% faster.

sync kqueue branch with HEAD

Pull up revision 1.44 (requested by chuq in ticket #760):
cpu_fork: clear PSTATE_PEF for a child process, reviewed by thorpej

catch up with -current.

cpu_preempt fix, adjust pc/npc in syscall, use T_AST for cpu_preempt.

Catch up to -current.

sync

cpu_fork: clear PSTATE_PEF for a child process, reviewed by thorpej

catch up with -current.

No longer need to pull in lwp.h; proc.h pulls it in for us.

Curproc->curlwp renaming.

Change uses of "curproc->l_proc" back to "curproc", which is more like the
original use. Bare uses of "curproc" are now "curlwp".

"curproc" is now #defined in proc.h as ((curlwp) ? (curlwp)->l_proc) : NULL)
so that it is always safe to reference curproc (*de*referencing curproc
is another story, but that's always been true).

catch up with -current on kqueue branch

Catch up to -current.

Pass on the P_32 flag on fork and support fork syscall returns using
%g7 as the completion address.

Trapframes only have locals or ins if the kernel is compiled DEBUG.

Implement upcalls and cpu_preempt().

Cleanup.

old stuff(single-threaded) works

more bits to SA

make kernel compile

cpu_fork() -> cpu_lwp_fork().  This logically forks an LWP, not a
complete process.  As noted by Gregory McGarry on tech-kern.

Catch up with -current.

Update the kqueue branch to HEAD.

file vm_machdep.c was added on branch nathanw_sa on 2001-12-08 04:22:23 +0000

Update pmap_update to now take the updated pmap as an argument.
This will allow improvements to the pmaps so that they can more easily defer expensive operations, eg tlb/cache flush, til the last possible moment.

Currently this is a no-op on most platforms, so they should see no difference.

Reviewed by Jason.

Merge Aug 24 -current into the kqueue branch.

use pmap_k* for buffer cache pages.

in vunmapbuf(), call pmap_*remove() explicitly since uvm_km_free_wakeup()
will soon no longer do it for us.

Handle proper saving of the fpstate.

Catch up to -current.

Sprinkle pmap_update() calls after calls to:
- pmap_enter()
- pmap_remove()
- pmap_protect()
- pmap_kenter_pa()
- pmap_kremove()
as described in pmap(9).

These calls are relatively conservative.  It may be possible to
optimize these a little more.

Sync with HEAD

Remove spurious `#define DEBUG'

Sync with HEAD (for UBC fixes).

Don't use rwindow_save() since the stack has already been made COW.

Sync with HEAD.

Initialize pcb_lastcall so db_dump_pcb() will not bomb on non-DEBUG kernels.

Update thorpej_scsipi to -current as of a month ago
A i386 GENERIC kernel compiles without the siop, ahc and bha drivers
(will be updated later). i386 IDE/ATAPI and ncr work, as well as
sparc/esp_sbus. alpha should work as well (untested yet).
siop, ahc and bha will be updated once I've updated the branch to current
-current, as well as machine-dependant code.

remove unneeded cast.

Remove unneeded cache flushes.

Don't take protection faults on I/O mappings.

pull up 1.30 (approved by thorpej):
>Cleanup trapstate handling and garbage collect old stuff.

Cleanup trapstate handling and garbage collect old stuff.

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

remove/move more mach vm header files:

	<vm/pglist.h> -> <uvm/uvm_pglist.h>
	<vm/vm_inherit.h> -> <uvm/uvm_inherit.h>
	<vm/vm_kern.h> -> into <uvm/uvm_extern.h>
	<vm/vm_object.h> -> nothing
	<vm/vm_pager.h> -> into <uvm/uvm_pager.h>

also includes a bunch of <vm/vm_page.h> include removals (due to redudancy
with <vm/vm.h>), and a scattering of other similar headers.

Sync w/ netbsd-1-5-base.

Rather than starting init and creating kthreads by forking and then
doing a cpu_set_kpc(), just pass the entry point and argument all
the way down the fork path starting with fork1().  In order to
avoid special-casing the normal fork in every cpu_fork(), MI code
passes down child_return() and the child process pointer explicitly.

This fixes a race condition on multiprocessor systems; a CPU could
grab the newly created processes (which has been placed on a run queue)
before cpu_set_kpc() would be performed.

Merge parts of chs-ubc2 into the trunk:
* Remove the casts to vaddr_t from the round_page() and trunc_page() macros to
  make them type-generic, which is necessary i.e. to operate on file offsets
  without truncating them.
* In due course, cast pointer arguments to these macros to an appropriate
  integral type (paddr_t, vaddr_t).

Originally done by Chuck Silvers, updated by myself.

Fix PR9240: comment above cpu_fork() out of synch with reality on most ports.
(comment change only, but was wrong for more than just i386).

Update COMPAT_NETBSD32 stuff.

Pull up to last week's -current.

CL* discarding.

Sync with -current

Update for pmap_enter() API change.  No functional difference.

Explicitly use 32-bit and 64-bit types and add some of the hooks needed for
32-bit coredumps.

Update to post 1.4.

Update from trunk.

Change the pmap_extract() interface to:
	boolean_t pmap_extract(pmap_t, vaddr_t, paddr_t *);
This makes it possible for the pmap to map physical address 0.

Sync w/ -current.

Generally update the comment above vunmapbuf().

Generally update the comment above the vmapbuf() implementations.

Allow the caller to specify a stack for the child process.  If NULL,
the child inherits the stack pointer from the parent (traditional
behavior).  Like the signal stack, the stack area is secified as
a low address and a size; machine-dependent code accounts for stack
direction.

This is required for clone(2).

Changes for modified pmap_enter() API:
* Map the message buffer with access_type = VM_PROT_READ|VM_PROT_WRITE `just
  because'.
* Map the file system buffers with access_type = VM_PROT_READ|VM_PROT_WRITE to
  avoid possible problems with pagemove().
* Do not use VM_PROT_EXEC with either of the above.
* Map pages for /dev/mem with access_type = prot.  Also, DO NOT use
  pmap_kenter() for this, as we DO NOT want to lose modification information.
* Map pages in dumpsys() with VM_PROT_READ.
* Map pages in m68k mappedcopyin()/mappedcopyout() and writeback() with
  access_type = prot.
* For now, bus_dma*(), pmap_map(), vmapbuf(), and similar functions still use
  access_type = 0.  This should probably be revisited.

completely remove Mach VM support.  all that is left is the all the
header files as UVM still uses (most of) these.

retire _LP64; use compiler provided __arch64__, but still defined _LP64 where we used to anyway.

Changes to support fork_kthread():
- cpu_set_kpc() now takes void *arg third argument, passed to the
  entry point.
- cpu_fork() allows parent to be non-curproc iff parent is proc0.
  When forking non-curproc, assume its state has already been saved.
- Adjust various pieces of machine-dependent code to account of all of this.

In cpu_coredump(), use MID_MACHINE rather than MID_* (whatever it expands
to).

Use MID_MACHINE rather than MID_SPARC in cpu_coredump(), and add a comment
about dumping a SPARC32 core file if we're using emul_sparc32.

Adjust for the new "reaper" kernel thread: do not free the vmspace and
u-area in machine-dependent code.  Instead, call exit2() to schedule
the reaper to free them for us, once it is safe to do so (i.e. we are
no longer running on the dead proc's vmspace and stack).

32-bit fixup.

It slices.  It dices.  It does everything except exec a sparc32_compat init.

Some more 64-bit cleanup.  Now everything compiles.

Remove dvma_mapin() and other cruft.

Merge paddr_t changes into the main branch.

Revert cdevsw mmap routines to return int.

Split vm_offset_t and vm_size_t into paddr_t, psize_t, vaddr_t, and vsize_t.

Don't cast the null residual pointer passed to vn_rdwr().

General update:

	Added genassym.cf
	Removed lderr which should never have gotten in
	Removed lots of dead code from locore.s
	Added some softint stuff to intr.c
	Added support for halt -p
	esp and le both use bus_dmamap_*() functions now
		instead of kdvma_mapin()
	groundwork for PCI (but we still have no drivers for
		any sun4u PCI devices)

Import of sparc64.

Initial revision