 @@ -1,3916 +1,3926 @@
-/* $NetBSD: pmap.c,v 1.287 2021/05/30 06:41:19 thorpej Exp $ */
+/* $NetBSD: pmap.c,v 1.288 2021/05/30 13:34:21 thorpej Exp $ */
 /*-
  * Copyright (c) 1998, 1999, 2000, 2001, 2007, 2008, 2020
  * 	The NetBSD Foundation, Inc.
  * All rights reserved.
+ *
  * This code is derived from software contributed to The NetBSD Foundation
  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
  * NASA Ames Research Center, by Andrew Doran and Mindaugas Rasiukevicius,
  * and by Chris G. Demetriou.
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
+ *
  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  * POSSIBILITY OF SUCH DAMAGE.
  */
 /*
  * Copyright (c) 1991, 1993
  *	The Regents of the University of California.  All rights reserved.
+ *
  * This code is derived from software contributed to Berkeley by
  * the Systems Programming Group of the University of Utah Computer
  * Science Department.
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  * 3. Neither the name of the University nor the names of its contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
+ *
  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
+ *
  *	@(#)pmap.c	8.6 (Berkeley) 5/27/94
  */
 /*
  * DEC Alpha physical map management code.
+ *
  * History:
+ *
  *	This pmap started life as a Motorola 68851/68030 pmap,
  *	written by Mike Hibler at the University of Utah.
+ *
  *	It was modified for the DEC Alpha by Chris Demetriou
  *	at Carnegie Mellon University.
+ *
  *	Support for non-contiguous physical memory was added by
  *	Jason R. Thorpe of the Numerical Aerospace Simulation
  *	Facility, NASA Ames Research Center and Chris Demetriou.
+ *
  *	Page table management and a major cleanup were undertaken
  *	by Jason R. Thorpe, with lots of help from Ross Harvey of
  *	Avalon Computer Systems and from Chris Demetriou.
+ *
  *	Support for the new UVM pmap interface was written by
  *	Jason R. Thorpe.
+ *
  *	Support for ASNs was written by Jason R. Thorpe, again
  *	with help from Chris Demetriou and Ross Harvey.
+ *
  *	The locking protocol was written by Jason R. Thorpe,
  *	using Chuck Cranor's i386 pmap for UVM as a model.
+ *
  *	TLB shootdown code was written (and then subsequently
  *	rewritten some years later, borrowing some ideas from
  *	the x86 pmap) by Jason R. Thorpe.
+ *
  *	Multiprocessor modifications by Andrew Doran and
  *	Jason R. Thorpe.
+ *
  * Notes:
+ *
  *	All user page table access is done via K0SEG.  Kernel
  *	page table access is done via the recursive Virtual Page
  *	Table becase kernel PT pages are pre-allocated and never
  *	freed, so no VPT fault handling is requiried.
  */
 /*
  *	Manages physical address maps.
+ *
  *	Since the information managed by this module is
  *	also stored by the logical address mapping module,
  *	this module may throw away valid virtual-to-physical
  *	mappings at almost any time.  However, invalidations
  *	of virtual-to-physical mappings must be done as
  *	requested.
+ *
  *	In order to cope with hardware architectures which
  *	make virtual-to-physical map invalidates expensive,
  *	this module may delay invalidate or reduced protection
  *	operations until such time as they are actually
  *	necessary.  This module is given full information as
  *	to which processors are currently using which maps,
  *	and to when physical maps must be made correct.
  */
 #include "opt_lockdebug.h"
 #include "opt_sysv.h"
 #include "opt_multiprocessor.h"
 #include <sys/cdefs.h>			/* RCS ID & Copyright macro defns */
-__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.287 2021/05/30 06:41:19 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.288 2021/05/30 13:34:21 thorpej Exp $");
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/kernel.h>
 #include <sys/proc.h>
 #include <sys/malloc.h>
 #include <sys/pool.h>
 #include <sys/buf.h>
 #include <sys/evcnt.h>
 #include <sys/atomic.h>
 #include <sys/cpu.h>
 #include <uvm/uvm.h>
 #if defined(MULTIPROCESSOR)
 #include <machine/rpb.h>
 #endif
 #ifdef DEBUG
 #define	PDB_FOLLOW	0x0001
 #define	PDB_INIT	0x0002
 #define	PDB_ENTER	0x0004
 #define	PDB_REMOVE	0x0008
 #define	PDB_CREATE	0x0010
 #define	PDB_PTPAGE	0x0020
 #define	PDB_ASN		0x0040
 #define	PDB_BITS	0x0080
 #define	PDB_COLLECT	0x0100
 #define	PDB_PROTECT	0x0200
 #define	PDB_BOOTSTRAP	0x1000
 #define	PDB_PARANOIA	0x2000
 #define	PDB_WIRING	0x4000
 #define	PDB_PVDUMP	0x8000
 int debugmap = 0;
 int pmapdebug = PDB_PARANOIA;
 #endif
 #if defined(MULTIPROCESSOR)
 #define	PMAP_MP(x)	x
 #else
 #define	PMAP_MP(x)	__nothing
 #endif /* MULTIPROCESSOR */
 /*
  * Given a map and a machine independent protection code,
  * convert to an alpha protection code.
  */
 #define pte_prot(m, p)	(protection_codes[m == pmap_kernel() ? 0 : 1][p])
 static int	protection_codes[2][8] __read_mostly;
 /*
  * kernel_lev1map:
+ *
  *	Kernel level 1 page table.  This maps all kernel level 2
  *	page table pages, and is used as a template for all user
  *	pmap level 1 page tables.  When a new user level 1 page
  *	table is allocated, all kernel_lev1map PTEs for kernel
  *	addresses are copied to the new map.
+ *
  *	The kernel also has an initial set of kernel level 2 page
  *	table pages.  These map the kernel level 3 page table pages.
  *	As kernel level 3 page table pages are added, more level 2
  *	page table pages may be added to map them.  These pages are
  *	never freed.
+ *
  *	Finally, the kernel also has an initial set of kernel level
  *	3 page table pages.  These map pages in K1SEG.  More level
  *	3 page table pages may be added at run-time if additional
  *	K1SEG address space is required.  These pages are never freed.
+ *
  * NOTE: When mappings are inserted into the kernel pmap, all
  * level 2 and level 3 page table pages must already be allocated
  * and mapped into the parent page table.
  */
 pt_entry_t	*kernel_lev1map __read_mostly;
 /*
  * Virtual Page Table.
  */
 static pt_entry_t *VPT __read_mostly;
 static struct {
 	struct pmap k_pmap;
 } kernel_pmap_store __cacheline_aligned;
 struct pmap *const kernel_pmap_ptr = &kernel_pmap_store.k_pmap;
 /* PA of first available physical page */
 paddr_t    	avail_start __read_mostly;
 /* PA of last available physical page */
 paddr_t		avail_end __read_mostly;
 /* VA of last avail page (end of kernel AS) */
 static vaddr_t	virtual_end __read_mostly;
 /* Has pmap_init completed? */
 static bool pmap_initialized __read_mostly;
 /* Instrumentation */
 u_long		pmap_pages_stolen __read_mostly;
 /*
  * This variable contains the number of CPU IDs we need to allocate
  * space for when allocating the pmap structure.  It is used to
  * size a per-CPU array of ASN and ASN Generation number.
  */
 static u_long 	pmap_ncpuids __read_mostly;
 #ifndef PMAP_PV_LOWAT
 #define	PMAP_PV_LOWAT	16
 #endif
 int		pmap_pv_lowat __read_mostly = PMAP_PV_LOWAT;
 /*
  * List of all pmaps, used to update them when e.g. additional kernel
  * page tables are allocated.  This list is kept LRU-ordered by
  * pmap_activate().
  */
 static TAILQ_HEAD(, pmap) pmap_all_pmaps __cacheline_aligned;
 /*
  * The pools from which pmap structures and sub-structures are allocated.
  */
 static struct pool_cache pmap_pmap_cache __read_mostly;
 static struct pool_cache pmap_l1pt_cache __read_mostly;
 static struct pool_cache pmap_pv_cache __read_mostly;
 CTASSERT(offsetof(struct pmap, pm_percpu[0]) == COHERENCY_UNIT);
 CTASSERT(PMAP_SIZEOF(ALPHA_MAXPROCS) < ALPHA_PGBYTES);
 CTASSERT(sizeof(struct pmap_percpu) == COHERENCY_UNIT);
 /*
  * Address Space Numbers.
+ *
  * On many implementations of the Alpha architecture, the TLB entries and
  * I-cache blocks are tagged with a unique number within an implementation-
  * specified range.  When a process context becomes active, the ASN is used
  * to match TLB entries; if a TLB entry for a particular VA does not match
  * the current ASN, it is ignored (one could think of the processor as
  * having a collection of <max ASN> separate TLBs).  This allows operating
  * system software to skip the TLB flush that would otherwise be necessary
  * at context switch time.
+ *
  * Alpha PTEs have a bit in them (PG_ASM - Address Space Match) that
  * causes TLB entries to match any ASN.  The PALcode also provides
  * a TBI (Translation Buffer Invalidate) operation that flushes all
  * TLB entries that _do not_ have PG_ASM.  We use this bit for kernel
  * mappings, so that invalidation of all user mappings does not invalidate
  * kernel mappings (which are consistent across all processes).
+ *
  * pmap_next_asn always indicates to the next ASN to use.  When
  * pmap_next_asn exceeds pmap_max_asn, we start a new ASN generation.
+ *
  * When a new ASN generation is created, the per-process (i.e. non-PG_ASM)
  * TLB entries and the I-cache are flushed, the generation number is bumped,
  * and pmap_next_asn is changed to indicate the first non-reserved ASN.
+ *
  * We reserve ASN #0 for pmaps that use the global kernel_lev1map.  This
  * prevents the following scenario to ensure no accidental accesses to
  * user space for LWPs using the kernel pmap.  This is important because
  * the PALcode may use the recursive VPT to service TLB misses.
+ *
  * By reserving an ASN for the kernel, we are guaranteeing that an lwp
  * will not see any valid user space TLB entries until it passes through
  * pmap_activate() for the first time.
+ *
  * On processors that do not support ASNs, the PALcode invalidates
  * non-ASM TLB entries automatically on swpctx.  We completely skip
  * the ASN machinery in this case because the PALcode neither reads
  * nor writes that field of the HWPCB.
  */
 /* max ASN supported by the system */
 static u_int	pmap_max_asn __read_mostly;
 /*
  * Locking:
+ *
  *	READ/WRITE LOCKS
  *	----------------
+ *
  *	* pmap_main_lock - This lock is used to prevent deadlock and/or
  *	  provide mutex access to the pmap module.  Most operations lock
  *	  the pmap first, then PV lists as needed.  However, some operations,
  *	  such as pmap_page_protect(), lock the PV lists before locking
  *	  the pmaps.  To prevent deadlock, we require a mutex lock on the
  *	  pmap module if locking in the PV->pmap direction.  This is
  *	  implemented by acquiring a (shared) read lock on pmap_main_lock
  *	  if locking pmap->PV and a (exclusive) write lock if locking in
  *	  the PV->pmap direction.  Since only one thread can hold a write
  *	  lock at a time, this provides the mutex.
+ *
  *	MUTEXES
  *	-------
+ *
  *	* pmap lock (global hash) - These locks protect the pmap structures.
+ *
  *	* pmap activation lock (global hash) - These IPL_SCHED spin locks
  *	  synchronize pmap_activate() and TLB shootdowns.  This has a lock
  *	  ordering constraint with the tlb_lock:
+ *
  *		tlb_lock -> pmap activation lock
+ *
  *	* pvh_lock (global hash) - These locks protect the PV lists for
  *	  managed pages.
+ *
  *	* tlb_lock - This IPL_VM lock serializes local and remote TLB
  *	  invalidation.
+ *
  *	* pmap_all_pmaps_lock - This lock protects the global list of
  *	  all pmaps.
+ *
  *	* pmap_growkernel_lock - This lock protects pmap_growkernel()
  *	  and the virtual_end variable.
+ *
  *	  There is a lock ordering constraint for pmap_growkernel_lock.
  *	  pmap_growkernel() acquires the locks in the following order:
+ *
  *		pmap_growkernel_lock (write) -> pmap_all_pmaps_lock ->
  *		    pmap lock
+ *
  *	  We need to ensure consistency between user pmaps and the
  *	  kernel_lev1map.  For this reason, pmap_growkernel_lock must
  *	  be held to prevent kernel_lev1map changing across pmaps
  *	  being added to / removed from the global pmaps list.
+ *
  *	Address space number management (global ASN counters and per-pmap
  *	ASN state) are not locked; they use arrays of values indexed
  *	per-processor.
+ *
  *	All internal functions which operate on a pmap are called
  *	with the pmap already locked by the caller (which will be
  *	an interface function).
  */
 static krwlock_t pmap_main_lock __cacheline_aligned;
 static kmutex_t pmap_all_pmaps_lock __cacheline_aligned;
 static krwlock_t pmap_growkernel_lock __cacheline_aligned;
 #define	PMAP_MAP_TO_HEAD_LOCK()		rw_enter(&pmap_main_lock, RW_READER)
 #define	PMAP_MAP_TO_HEAD_UNLOCK()	rw_exit(&pmap_main_lock)
 #define	PMAP_HEAD_TO_MAP_LOCK()		rw_enter(&pmap_main_lock, RW_WRITER)
 #define	PMAP_HEAD_TO_MAP_UNLOCK()	rw_exit(&pmap_main_lock)
 static union {
 	kmutex_t	lock;
 	uint8_t		pad[COHERENCY_UNIT];
 } pmap_pvh_locks[64] __cacheline_aligned;
 #define	PVH_LOCK_HASH(pg)						\
 	((((uintptr_t)(pg)) >> 6) & 63)
 static inline kmutex_t *
 pmap_pvh_lock(struct vm_page *pg)
+{
 	return &pmap_pvh_locks[PVH_LOCK_HASH(pg)].lock;
+}
 static union {
 	struct {
 		kmutex_t	lock;
 		kmutex_t	activation_lock;
 	} locks;
 	uint8_t		pad[COHERENCY_UNIT];
 } pmap_pmap_locks[64] __cacheline_aligned;
 #define	PMAP_LOCK_HASH(pm)						\
 	((((uintptr_t)(pm)) >> 6) & 63)
 static inline kmutex_t *
 pmap_pmap_lock(pmap_t const pmap)
+{
 	return &pmap_pmap_locks[PMAP_LOCK_HASH(pmap)].locks.lock;
+}
 static inline kmutex_t *
 pmap_activation_lock(pmap_t const pmap)
+{
 	return &pmap_pmap_locks[PMAP_LOCK_HASH(pmap)].locks.activation_lock;
+}
 #define	PMAP_LOCK(pmap)		mutex_enter(pmap_pmap_lock(pmap))
 #define	PMAP_UNLOCK(pmap)	mutex_exit(pmap_pmap_lock(pmap))
 #define	PMAP_ACT_LOCK(pmap)	mutex_spin_enter(pmap_activation_lock(pmap))
 #define	PMAP_ACT_TRYLOCK(pmap)	mutex_tryenter(pmap_activation_lock(pmap))
 #define	PMAP_ACT_UNLOCK(pmap)	mutex_spin_exit(pmap_activation_lock(pmap))
 #if defined(MULTIPROCESSOR)
 #define	pmap_all_cpus()		cpus_running
 #else
 #define	pmap_all_cpus()		~0UL
 #endif /* MULTIPROCESSOR */
 /*
  * Generic routine for freeing pages on a pmap_pagelist back to
  * the system.
  */
 static void
 pmap_pagelist_free(struct pmap_pagelist * const list)
+{
 	struct vm_page *pg;
 	while ((pg = LIST_FIRST(list)) != NULL) {
 		LIST_REMOVE(pg, pageq.list);
 		uvm_pagefree(pg);
+	}
+}
 /*
  * TLB management.
+ *
  * TLB invalidations need to be performed on local and remote CPUs
  * whenever parts of the PTE that the hardware or PALcode understands
  * changes.  In order amortize the cost of these operations, we will
  * queue up to 8 addresses to invalidate in a batch.  Any more than
  * that, and we will hit the entire TLB.
+ *
  * Some things that add complexity:
+ *
  * ==> ASNs. A CPU may have valid TLB entries for other than the current
  *     address spaace.  We can only invalidate TLB entries for the current
  *     address space, so when asked to invalidate a VA for the non-current
  *     pmap on a given CPU, we simply invalidate the ASN for that pmap,CPU
  *     tuple so that new one is allocated on the next activation on that
  *     CPU.  N.B. that for CPUs that don't implement ASNs, SWPCTX does all
  *     the work necessary, so we can skip some work in the pmap module
  *     itself.
+ *
  *     When a pmap is activated on a given CPU, we set a corresponding
  *     bit in pmap::pm_cpus, indicating that it potentially has valid
  *     TLB entries for that address space.  This bitmap is then used to
  *     determine which remote CPUs need to be notified of invalidations.
  *     The bit is cleared when the ASN is invalidated on that CPU.
+ *
  *     In order to serialize with activating an address space on a
  *     given CPU (that we can reliably send notifications only to
  *     relevant remote CPUs), we acquire the pmap lock in pmap_activate()
  *     and also hold the lock while remote shootdowns take place.
  *     This does not apply to the kernel pmap; all CPUs are notified about
  *     invalidations for the kernel pmap, and the pmap lock is not held
  *     in pmap_activate() for the kernel pmap.
+ *
  * ==> P->V operations (e.g. pmap_page_protect()) may require sending
  *     invalidations for multiple address spaces.  We only track one
  *     address space at a time, and if we encounter more than one, then
  *     the notification each CPU gets is to hit the entire TLB.  Note
  *     also that we can't serialize with pmap_activate() in this case,
  *     so all CPUs will get the notification, and they check when
  *     processing the notification if the pmap is current on that CPU.
+ *
  * Invalidation information is gathered into a pmap_tlb_context structure
  * that includes room for 8 VAs, the pmap the VAs belong to, a bitmap of
  * CPUs to be notified, and a list for PT pages that are freed during
  * removal off mappings.  The number of valid addresses in the list as
  * well as flags are sqeezed into the lower bits of the first two VAs.
  * Storage for this structure is allocated on the stack.  We need to be
  * careful to keep the size of this struture under control.
+ *
  * When notifying remote CPUs, we acquire the tlb_lock (which also
  * blocks IPIs), record the pointer to our context structure, set a
  * global bitmap off CPUs to be notified, and then send the IPIs to
  * each victim.  While the other CPUs are in-flight, we then perform
  * any invalidations necessary on the local CPU.  Once that is done,
  * we then wait the the global context pointer to be cleared, which
  * will be done by the final remote CPU to complete their work. This
  * method reduces cache line contention during pocessing.
+ *
  * When removing mappings in user pmaps, this implemention frees page
  * table pages back to the VM system once they contain no valid mappings.
  * As we do this, we must ensure to invalidate TLB entries that the
  * CPU might hold for the respective recursive VPT mappings.  This must
  * be done whenever an L1 or L2 PTE is invalidated.  Until these VPT
  * translations are invalidated, the PT pages must not be reused.  For
  * this reason, we keep a list of freed PT pages in the context stucture
  * and drain them off once all invalidations are complete.
+ *
  * NOTE: The value of TLB_CTX_MAXVA is tuned to accommodate the UBC
  * window size (defined as 64KB on alpha in <machine/vmparam.h>).
  */
 #define	TLB_CTX_MAXVA		8
 #define	TLB_CTX_ALLVA		PAGE_MASK
 #define	TLB_CTX_F_ASM		__BIT(0)
 #define	TLB_CTX_F_IMB		__BIT(1)
 #define	TLB_CTX_F_KIMB		__BIT(2)
 #define	TLB_CTX_F_PV		__BIT(3)
 #define	TLB_CTX_F_MULTI		__BIT(4)
 #define	TLB_CTX_COUNT(ctx)	((ctx)->t_addrdata[0] & PAGE_MASK)
 #define	TLB_CTX_INC_COUNT(ctx)	 (ctx)->t_addrdata[0]++
 #define	TLB_CTX_SET_ALLVA(ctx)	 (ctx)->t_addrdata[0] |= TLB_CTX_ALLVA
 #define	TLB_CTX_FLAGS(ctx)	((ctx)->t_addrdata[1] & PAGE_MASK)
 #define	TLB_CTX_SET_FLAG(ctx, f) (ctx)->t_addrdata[1] |= (f)
 #define	TLB_CTX_VA(ctx, i)	((ctx)->t_addrdata[(i)] & ~PAGE_MASK)
 #define	TLB_CTX_SETVA(ctx, i, va)					\
 	(ctx)->t_addrdata[(i)] = (va) | ((ctx)->t_addrdata[(i)] & PAGE_MASK)
 struct pmap_tlb_context {
 	uintptr_t	t_addrdata[TLB_CTX_MAXVA];
 	pmap_t		t_pmap;
 	struct pmap_pagelist t_freeptq;
 };
 static struct {
 	kmutex_t	lock;
 	struct evcnt	events;
 } tlb_shootdown __cacheline_aligned;
 #define	tlb_lock	tlb_shootdown.lock
 #define	tlb_evcnt	tlb_shootdown.events
 #if defined(MULTIPROCESSOR)
 static const struct pmap_tlb_context *tlb_context __cacheline_aligned;
 static unsigned long tlb_pending __cacheline_aligned;
 #endif /* MULTIPROCESSOR */
 #if defined(TLB_STATS)
 #define	TLB_COUNT_DECL(cnt)	static struct evcnt tlb_stat_##cnt
 #define	TLB_COUNT(cnt)		atomic_inc_64(&tlb_stat_##cnt .ev_count)
 #define	TLB_COUNT_ATTACH(cnt)						\
 	evcnt_attach_dynamic_nozero(&tlb_stat_##cnt, EVCNT_TYPE_MISC,	\
 	    NULL, "TLB", #cnt)
 TLB_COUNT_DECL(invalidate_multi_tbia);
 TLB_COUNT_DECL(invalidate_multi_tbiap);
 TLB_COUNT_DECL(invalidate_multi_imb);
 TLB_COUNT_DECL(invalidate_kern_tbia);
 TLB_COUNT_DECL(invalidate_kern_tbis);
 TLB_COUNT_DECL(invalidate_kern_imb);
 TLB_COUNT_DECL(invalidate_user_not_current);
 TLB_COUNT_DECL(invalidate_user_lazy_imb);
 TLB_COUNT_DECL(invalidate_user_tbiap);
 TLB_COUNT_DECL(invalidate_user_tbis);
 TLB_COUNT_DECL(shootdown_kernel);
 TLB_COUNT_DECL(shootdown_user);
 TLB_COUNT_DECL(shootdown_imb);
 TLB_COUNT_DECL(shootdown_kimb);
 TLB_COUNT_DECL(shootdown_overflow);
 TLB_COUNT_DECL(shootdown_all_user);
 TLB_COUNT_DECL(shootdown_all_user_imb);
 TLB_COUNT_DECL(shootdown_pv);
 TLB_COUNT_DECL(shootdown_pv_multi);
 TLB_COUNT_DECL(shootnow_over_notify);
 TLB_COUNT_DECL(shootnow_remote);
 TLB_COUNT_DECL(reason_remove_kernel);
 TLB_COUNT_DECL(reason_remove_user);
 TLB_COUNT_DECL(reason_page_protect_read);
 TLB_COUNT_DECL(reason_page_protect_none);
 TLB_COUNT_DECL(reason_protect);
 TLB_COUNT_DECL(reason_enter_kernel);
 TLB_COUNT_DECL(reason_enter_user);
 TLB_COUNT_DECL(reason_kenter);
 TLB_COUNT_DECL(reason_enter_l2pt_delref);
 TLB_COUNT_DECL(reason_enter_l3pt_delref);
 TLB_COUNT_DECL(reason_kremove);
 TLB_COUNT_DECL(reason_clear_modify);
 TLB_COUNT_DECL(reason_clear_reference);
 TLB_COUNT_DECL(reason_emulate_reference);
 TLB_COUNT_DECL(asn_reuse);
 TLB_COUNT_DECL(asn_newgen);
 TLB_COUNT_DECL(asn_assign);
 TLB_COUNT_DECL(activate_both_change);
 TLB_COUNT_DECL(activate_asn_change);
 TLB_COUNT_DECL(activate_ptbr_change);
 TLB_COUNT_DECL(activate_swpctx);
 TLB_COUNT_DECL(activate_skip_swpctx);
 #else /* ! TLB_STATS */
 #define	TLB_COUNT(cnt)		__nothing
 #define	TLB_COUNT_ATTACH(cnt)	__nothing
 #endif /* TLB_STATS */
 static void
 pmap_tlb_init(void)
+{
 	/* mutex is initialized in pmap_bootstrap(). */
 	evcnt_attach_dynamic_nozero(&tlb_evcnt, EVCNT_TYPE_MISC,
 	    NULL, "TLB", "shootdown");
 	TLB_COUNT_ATTACH(invalidate_multi_tbia);
 	TLB_COUNT_ATTACH(invalidate_multi_tbiap);
 	TLB_COUNT_ATTACH(invalidate_multi_imb);
 	TLB_COUNT_ATTACH(invalidate_kern_tbia);
 	TLB_COUNT_ATTACH(invalidate_kern_tbis);
 	TLB_COUNT_ATTACH(invalidate_kern_imb);
 	TLB_COUNT_ATTACH(invalidate_user_not_current);
 	TLB_COUNT_ATTACH(invalidate_user_lazy_imb);
 	TLB_COUNT_ATTACH(invalidate_user_tbiap);
 	TLB_COUNT_ATTACH(invalidate_user_tbis);
 	TLB_COUNT_ATTACH(shootdown_kernel);
 	TLB_COUNT_ATTACH(shootdown_user);
 	TLB_COUNT_ATTACH(shootdown_imb);
 	TLB_COUNT_ATTACH(shootdown_kimb);
 	TLB_COUNT_ATTACH(shootdown_overflow);
 	TLB_COUNT_ATTACH(shootdown_all_user);
 	TLB_COUNT_ATTACH(shootdown_all_user_imb);
 	TLB_COUNT_ATTACH(shootdown_pv);
 	TLB_COUNT_ATTACH(shootdown_pv_multi);
 	TLB_COUNT_ATTACH(shootnow_over_notify);
 	TLB_COUNT_ATTACH(shootnow_remote);
 	TLB_COUNT_ATTACH(reason_remove_kernel);
 	TLB_COUNT_ATTACH(reason_remove_user);
 	TLB_COUNT_ATTACH(reason_page_protect_read);
 	TLB_COUNT_ATTACH(reason_page_protect_none);
 	TLB_COUNT_ATTACH(reason_protect);
 	TLB_COUNT_ATTACH(reason_enter_kernel);
 	TLB_COUNT_ATTACH(reason_enter_user);
 	TLB_COUNT_ATTACH(reason_kenter);
 	TLB_COUNT_ATTACH(reason_enter_l2pt_delref);
 	TLB_COUNT_ATTACH(reason_enter_l3pt_delref);
 	TLB_COUNT_ATTACH(reason_kremove);
 	TLB_COUNT_ATTACH(reason_clear_modify);
 	TLB_COUNT_ATTACH(reason_clear_reference);
 	TLB_COUNT_ATTACH(asn_reuse);
 	TLB_COUNT_ATTACH(asn_newgen);
 	TLB_COUNT_ATTACH(asn_assign);
 	TLB_COUNT_ATTACH(activate_both_change);
 	TLB_COUNT_ATTACH(activate_asn_change);
 	TLB_COUNT_ATTACH(activate_ptbr_change);
 	TLB_COUNT_ATTACH(activate_swpctx);
 	TLB_COUNT_ATTACH(activate_skip_swpctx);
+}
 static inline void
 pmap_tlb_context_init(struct pmap_tlb_context * const tlbctx, uintptr_t flags)
+{
 	/* Initialize the minimum number of fields. */
 	tlbctx->t_addrdata[0] = 0;
 	tlbctx->t_addrdata[1] = flags;
 	tlbctx->t_pmap = NULL;
 	LIST_INIT(&tlbctx->t_freeptq);
+}
 static void
 pmap_tlb_shootdown_internal(pmap_t const pmap, vaddr_t const va,
     pt_entry_t const pte_bits, struct pmap_tlb_context * const tlbctx)
+{
 	KASSERT(pmap != NULL);
 	KASSERT((va & PAGE_MASK) == 0);
 	/*
 	 * Figure out who needs to hear about this, and the scope
 	 * of an all-entries invalidate.
 	 */
 	if (pmap == pmap_kernel()) {
 		TLB_COUNT(shootdown_kernel);
 		KASSERT(pte_bits & PG_ASM);
 		TLB_CTX_SET_FLAG(tlbctx, TLB_CTX_F_ASM);
 		/* Note if an I-stream sync is also needed. */
 		if (pte_bits & PG_EXEC) {
 			TLB_COUNT(shootdown_kimb);
 			TLB_CTX_SET_FLAG(tlbctx, TLB_CTX_F_KIMB);
+		}
 	} else {
 		TLB_COUNT(shootdown_user);
 		KASSERT((pte_bits & PG_ASM) == 0);
 		/* Note if an I-stream sync is also needed. */
 		if (pte_bits & PG_EXEC) {
 			TLB_COUNT(shootdown_imb);
 			TLB_CTX_SET_FLAG(tlbctx, TLB_CTX_F_IMB);
+		}
+	}
 	KASSERT(tlbctx->t_pmap == NULL || tlbctx->t_pmap == pmap);
 	tlbctx->t_pmap = pmap;
 	/*
 	 * If we're already at the max, just tell each active CPU
 	 * to nail everything.
 	 */
 	const uintptr_t count = TLB_CTX_COUNT(tlbctx);
 	if (count > TLB_CTX_MAXVA) {
 		return;
+	}
 	if (count == TLB_CTX_MAXVA) {
 		TLB_COUNT(shootdown_overflow);
 		TLB_CTX_SET_ALLVA(tlbctx);
 		return;
+	}
 	TLB_CTX_SETVA(tlbctx, count, va);
 	TLB_CTX_INC_COUNT(tlbctx);
+}
 static void
 pmap_tlb_shootdown(pmap_t const pmap, vaddr_t const va,
     pt_entry_t const pte_bits, struct pmap_tlb_context * const tlbctx)
+{
 	KASSERT((TLB_CTX_FLAGS(tlbctx) & TLB_CTX_F_PV) == 0);
 	pmap_tlb_shootdown_internal(pmap, va, pte_bits, tlbctx);
+}
 static void
 pmap_tlb_shootdown_all_user(pmap_t const pmap, pt_entry_t const pte_bits,
     struct pmap_tlb_context * const tlbctx)
+{
 	KASSERT(pmap != pmap_kernel());
 	TLB_COUNT(shootdown_all_user);
 	/* Note if an I-stream sync is also needed. */
 	if (pte_bits & PG_EXEC) {
 		TLB_COUNT(shootdown_all_user_imb);
 		TLB_CTX_SET_FLAG(tlbctx, TLB_CTX_F_IMB);
+	}
 	if (TLB_CTX_FLAGS(tlbctx) & TLB_CTX_F_PV) {
 		if (tlbctx->t_pmap == NULL || tlbctx->t_pmap == pmap) {
 			if (tlbctx->t_pmap == NULL) {
 				pmap_reference(pmap);
 				tlbctx->t_pmap = pmap;
+			}
 		} else {
 			TLB_CTX_SET_FLAG(tlbctx, TLB_CTX_F_MULTI);
+		}
 	} else {
 		KASSERT(tlbctx->t_pmap == NULL || tlbctx->t_pmap == pmap);
 		tlbctx->t_pmap = pmap;
+	}
 	TLB_CTX_SET_ALLVA(tlbctx);
+}
 static void
 pmap_tlb_shootdown_pv(pmap_t const pmap, vaddr_t const va,
     pt_entry_t const pte_bits, struct pmap_tlb_context * const tlbctx)
+{
 	KASSERT(TLB_CTX_FLAGS(tlbctx) & TLB_CTX_F_PV);
 	TLB_COUNT(shootdown_pv);
 	if (tlbctx->t_pmap == NULL || tlbctx->t_pmap == pmap) {
 		if (tlbctx->t_pmap == NULL) {
 			pmap_reference(pmap);
 			tlbctx->t_pmap = pmap;
+		}
 		pmap_tlb_shootdown_internal(pmap, va, pte_bits, tlbctx);
 	} else {
 		TLB_COUNT(shootdown_pv_multi);
 		uintptr_t flags = TLB_CTX_F_MULTI;
 		if (pmap == pmap_kernel()) {
 			KASSERT(pte_bits & PG_ASM);
 			flags |= TLB_CTX_F_ASM;
 		} else {
 			KASSERT((pte_bits & PG_ASM) == 0);
+		}
 		/*
 		 * No need to distinguish between kernel and user IMB
 		 * here; see pmap_tlb_invalidate_multi().
 		 */
 		if (pte_bits & PG_EXEC) {
 			flags |= TLB_CTX_F_IMB;
+		}
 		TLB_CTX_SET_ALLVA(tlbctx);
 		TLB_CTX_SET_FLAG(tlbctx, flags);
+	}
+}
 static void
 pmap_tlb_invalidate_multi(const struct pmap_tlb_context * const tlbctx)
+{
 	if (TLB_CTX_FLAGS(tlbctx) & TLB_CTX_F_ASM) {
 		TLB_COUNT(invalidate_multi_tbia);
 		ALPHA_TBIA();
 	} else {
 		TLB_COUNT(invalidate_multi_tbiap);
 		ALPHA_TBIAP();
+	}
 	if (TLB_CTX_FLAGS(tlbctx) & (TLB_CTX_F_IMB | TLB_CTX_F_KIMB)) {
 		TLB_COUNT(invalidate_multi_imb);
 		alpha_pal_imb();
+	}
+}
 static void
 pmap_tlb_invalidate_kernel(const struct pmap_tlb_context * const tlbctx)
+{
 	const uintptr_t count = TLB_CTX_COUNT(tlbctx);
 	if (count == TLB_CTX_ALLVA) {
 		TLB_COUNT(invalidate_kern_tbia);
 		ALPHA_TBIA();
 	} else {
 		TLB_COUNT(invalidate_kern_tbis);
 		for (uintptr_t i = 0; i < count; i++) {
 			ALPHA_TBIS(TLB_CTX_VA(tlbctx, i));
+		}
+	}
 	if (TLB_CTX_FLAGS(tlbctx) & TLB_CTX_F_KIMB) {
 		TLB_COUNT(invalidate_kern_imb);
 		alpha_pal_imb();
+	}
+}
 static void
 pmap_tlb_invalidate(const struct pmap_tlb_context * const tlbctx,
     const struct cpu_info * const ci)
+{
 	const uintptr_t count = TLB_CTX_COUNT(tlbctx);
 	if (TLB_CTX_FLAGS(tlbctx) & TLB_CTX_F_MULTI) {
 		pmap_tlb_invalidate_multi(tlbctx);
 		return;
+	}
 	if (TLB_CTX_FLAGS(tlbctx) & TLB_CTX_F_ASM) {
 		pmap_tlb_invalidate_kernel(tlbctx);
 		return;
+	}
 	KASSERT(kpreempt_disabled());
 	pmap_t const pmap = tlbctx->t_pmap;
 	KASSERT(pmap != NULL);
 	if (__predict_false(pmap != ci->ci_pmap)) {
 		TLB_COUNT(invalidate_user_not_current);
 		/*
 		 * For CPUs that don't implement ASNs, the SWPCTX call
 		 * does all of the TLB invalidation work for us.
 		 */
 		if (__predict_false(pmap_max_asn == 0)) {
 			return;
+		}
 		const u_long cpu_mask = 1UL << ci->ci_cpuid;
 		/*
 		 * We cannot directly invalidate the TLB in this case,
 		 * so force allocation of a new ASN when the pmap becomes
 		 * active again.
 		 */
 		pmap->pm_percpu[ci->ci_cpuid].pmc_asngen = PMAP_ASNGEN_INVALID;
 		atomic_and_ulong(&pmap->pm_cpus, ~cpu_mask);
 		/*
 		 * This isn't strictly necessary; when we allocate a
 		 * new ASN, we're going to clear this bit and skip
 		 * syncing the I-stream.  But we will keep this bit
 		 * of accounting for internal consistency.
 		 */
 		if (TLB_CTX_FLAGS(tlbctx) & TLB_CTX_F_IMB) {
 			pmap->pm_percpu[ci->ci_cpuid].pmc_needisync = 1;
+		}
 		return;
+	}
 	if (TLB_CTX_FLAGS(tlbctx) & TLB_CTX_F_IMB) {
 		TLB_COUNT(invalidate_user_lazy_imb);
 		pmap->pm_percpu[ci->ci_cpuid].pmc_needisync = 1;
+	}
 	if (count == TLB_CTX_ALLVA) {
 		/*
 		 * Another option here for CPUs that implement ASNs is
 		 * to allocate a new ASN and do a SWPCTX.  That's almost
 		 * certainly faster than a TBIAP, but would require us
 		 * to synchronize against IPIs in pmap_activate().
 		 */
 		TLB_COUNT(invalidate_user_tbiap);
 		KASSERT((TLB_CTX_FLAGS(tlbctx) & TLB_CTX_F_ASM) == 0);
 		ALPHA_TBIAP();
 	} else {
 		TLB_COUNT(invalidate_user_tbis);
 		for (uintptr_t i = 0; i < count; i++) {
 			ALPHA_TBIS(TLB_CTX_VA(tlbctx, i));
+		}
+	}
+}
 static void
 pmap_tlb_shootnow(const struct pmap_tlb_context * const tlbctx)
+{
 	if (TLB_CTX_COUNT(tlbctx) == 0) {
 		/* No work to do. */
 		return;
+	}
 	/*
 	 * Acquire the shootdown mutex.  This will also block IPL_VM
 	 * interrupts and disable preemption.  It is critically important
 	 * that IPIs not be blocked in this routine.
 	 */
 	KASSERT((alpha_pal_rdps() & ALPHA_PSL_IPL_MASK) < ALPHA_PSL_IPL_CLOCK);
 	mutex_spin_enter(&tlb_lock);
 	tlb_evcnt.ev_count++;
 	const struct cpu_info *ci = curcpu();
 	const u_long this_cpu = 1UL << ci->ci_cpuid;
 	u_long active_cpus;
 	bool activation_locked, activation_lock_tried;
 	/*
 	 * Figure out who to notify.  If it's for the kernel or
 	 * multiple aaddress spaces, we notify everybody.  If
 	 * it's a single user pmap, then we try to acquire the
 	 * activation lock so we can get an accurate accounting
 	 * of who needs to be notified.  If we can't acquire
 	 * the activation lock, then just notify everyone and
 	 * let them sort it out when they process the IPI.
 	 */
 	if (TLB_CTX_FLAGS(tlbctx) & (TLB_CTX_F_ASM | TLB_CTX_F_MULTI)) {
 		active_cpus = pmap_all_cpus();
 		activation_locked = false;
 		activation_lock_tried = false;
 	} else {
 		KASSERT(tlbctx->t_pmap != NULL);
 		activation_locked = PMAP_ACT_TRYLOCK(tlbctx->t_pmap);
 		if (__predict_true(activation_locked)) {
 			active_cpus = tlbctx->t_pmap->pm_cpus;
 		} else {
 			TLB_COUNT(shootnow_over_notify);
 			active_cpus = pmap_all_cpus();
+		}
 		activation_lock_tried = true;
+	}
 #if defined(MULTIPROCESSOR)
 	/*
 	 * If there are remote CPUs that need to do work, get them
 	 * started now.
 	 */
 	const u_long remote_cpus = active_cpus & ~this_cpu;
 	KASSERT(tlb_context == NULL);
 	if (remote_cpus) {
 		TLB_COUNT(shootnow_remote);
 		tlb_context = tlbctx;
 		tlb_pending = remote_cpus;
 		alpha_multicast_ipi(remote_cpus, ALPHA_IPI_SHOOTDOWN);
+	}
 #endif /* MULTIPROCESSOR */
 	/*
 	 * Now that the remotes have been notified, release the
 	 * activation lock.
 	 */
 	if (activation_lock_tried) {
 		if (activation_locked) {
 			KASSERT(tlbctx->t_pmap != NULL);
 			PMAP_ACT_UNLOCK(tlbctx->t_pmap);
+		}
 		/*
 		 * When we tried to acquire the activation lock, we
 		 * raised IPL to IPL_SCHED (even if we ultimately
 		 * failed to acquire the lock), which blocks out IPIs.
 		 * Force our IPL back down to IPL_VM so that we can
 		 * receive IPIs.
 		 */
 		alpha_pal_swpipl(IPL_VM);
+	}
 	/*
 	 * Do any work that we might need to do.  We don't need to
 	 * synchronize with activation here because we know that
 	 * for the current CPU, activation status will not change.
 	 */
 	if (active_cpus & this_cpu) {
 		pmap_tlb_invalidate(tlbctx, ci);
+	}
 #if defined(MULTIPROCESSOR)
 	/* Wait for remote CPUs to finish. */
 	if (remote_cpus) {
 		int backoff = SPINLOCK_BACKOFF_MIN;
 		u_int spins = 0;
 		while (atomic_load_acquire(&tlb_context) != NULL) {
 			SPINLOCK_BACKOFF(backoff);
 			if (spins++ > 0x0fffffff) {
 				printf("TLB LOCAL MASK  = 0x%016lx\n",
 				    this_cpu);
 				printf("TLB REMOTE MASK = 0x%016lx\n",
 				    remote_cpus);
 				printf("TLB REMOTE PENDING = 0x%016lx\n",
 				    tlb_pending);
 				printf("TLB CONTEXT = %p\n", tlb_context);
 				printf("TLB LOCAL IPL = %lu\n",
 				    alpha_pal_rdps() & ALPHA_PSL_IPL_MASK);
 				panic("pmap_tlb_shootnow");
+			}
+		}
+	}
 	KASSERT(tlb_context == NULL);
 #endif /* MULTIPROCESSOR */
 	mutex_spin_exit(&tlb_lock);
 	if (__predict_false(TLB_CTX_FLAGS(tlbctx) & TLB_CTX_F_PV)) {
 		/*
 		 * P->V TLB operations may operate on multiple pmaps.
 		 * The shootdown takes a reference on the first pmap it
 		 * encounters, in order to prevent it from disappearing,
 		 * in the hope that we end up with a single-pmap P->V
 		 * operation (instrumentation shows this is not rare).
+		 *
 		 * Once this shootdown is finished globally, we need to
 		 * release this extra reference.
 		 */
 		KASSERT(tlbctx->t_pmap != NULL);
 		pmap_destroy(tlbctx->t_pmap);
+	}
+}
 #if defined(MULTIPROCESSOR)
 void
 pmap_tlb_shootdown_ipi(struct cpu_info * const ci,
     struct trapframe * const tf __unused)
+{
 	KASSERT(tlb_context != NULL);
 	pmap_tlb_invalidate(tlb_context, ci);
 	if (atomic_and_ulong_nv(&tlb_pending, ~(1UL << ci->ci_cpuid)) == 0) {
 		atomic_store_release(&tlb_context, NULL);
+	}
+}
 #endif /* MULTIPROCESSOR */
 static __inline void
 pmap_tlb_ptpage_drain(struct pmap_tlb_context * const tlbctx)
+{
 	pmap_pagelist_free(&tlbctx->t_freeptq);
+}
 /*
  * Internal routines
  */
 static void	alpha_protection_init(void);
 static pt_entry_t pmap_remove_mapping(pmap_t, vaddr_t, pt_entry_t *, bool,
 				      pv_entry_t *,
 				      struct pmap_tlb_context *);
 static void	pmap_changebit(struct vm_page *, pt_entry_t, pt_entry_t,
 			       struct pmap_tlb_context *);
 /*
  * PT page management functions.
  */
 static int	pmap_ptpage_alloc(pmap_t, pt_entry_t *, int);
 static void	pmap_ptpage_free(pmap_t, pt_entry_t *,
 				 struct pmap_tlb_context *);
 static void	pmap_l3pt_delref(pmap_t, vaddr_t, pt_entry_t *,
 		     struct pmap_tlb_context *);
 static void	pmap_l2pt_delref(pmap_t, pt_entry_t *, pt_entry_t *,
 		     struct pmap_tlb_context *);
 static void	pmap_l1pt_delref(pmap_t, pt_entry_t *);
 static void	*pmap_l1pt_alloc(struct pool *, int);
 static void	pmap_l1pt_free(struct pool *, void *);
 static struct pool_allocator pmap_l1pt_allocator = {
 	pmap_l1pt_alloc, pmap_l1pt_free, 0,
 };
 static int	pmap_l1pt_ctor(void *, void *, int);
 /*
  * PV table management functions.
  */
 static int	pmap_pv_enter(pmap_t, struct vm_page *, vaddr_t, pt_entry_t *,
 			      bool, pv_entry_t);
 static void	pmap_pv_remove(pmap_t, struct vm_page *, vaddr_t, bool,
 			       pv_entry_t *);
 static void	*pmap_pv_page_alloc(struct pool *, int);
 static void	pmap_pv_page_free(struct pool *, void *);
 static struct pool_allocator pmap_pv_page_allocator = {
 	pmap_pv_page_alloc, pmap_pv_page_free, 0,
 };
 #ifdef DEBUG
 void	pmap_pv_dump(paddr_t);
 #endif
 #define	pmap_pv_alloc()		pool_cache_get(&pmap_pv_cache, PR_NOWAIT)
 #define	pmap_pv_free(pv)	pool_cache_put(&pmap_pv_cache, (pv))
 /*
  * ASN management functions.
  */
 static u_int	pmap_asn_alloc(pmap_t, struct cpu_info *);
 /*
  * Misc. functions.
  */
 static struct vm_page *pmap_physpage_alloc(int);
 static void	pmap_physpage_free(paddr_t);
 static int	pmap_physpage_addref(void *);
 static int	pmap_physpage_delref(void *);
 static bool	vtophys_internal(vaddr_t, paddr_t *p);
 /*
  * PMAP_KERNEL_PTE:
+ *
  *	Get a kernel PTE.
+ *
  *	If debugging, do a table walk.  If not debugging, just use
  *	the Virtual Page Table, since all kernel page tables are
  *	pre-allocated and mapped in.
  */
 #ifdef DEBUG
 #define	PMAP_KERNEL_PTE(va)						\
 ({									\
 	pt_entry_t *l1pte_, *l2pte_;					\
+									\
 	l1pte_ = pmap_l1pte(kernel_lev1map, va);			\
 	if (pmap_pte_v(l1pte_) == 0) {					\
 		printf("kernel level 1 PTE not valid, va 0x%lx "	\
 		    "(line %d)\n", (va), __LINE__);			\
 		panic("PMAP_KERNEL_PTE");				\
 	}								\
 	l2pte_ = pmap_l2pte(kernel_lev1map, va, l1pte_);		\
 	if (pmap_pte_v(l2pte_) == 0) {					\
 		printf("kernel level 2 PTE not valid, va 0x%lx "	\
 		    "(line %d)\n", (va), __LINE__);			\
 		panic("PMAP_KERNEL_PTE");				\
 	}								\
 	pmap_l3pte(kernel_lev1map, va, l2pte_);				\
 })
 #else
 #define	PMAP_KERNEL_PTE(va)	(&VPT[VPT_INDEX((va))])
 #endif
 /*
  * PMAP_STAT_{INCR,DECR}:
+ *
  *	Increment or decrement a pmap statistic.
  */
 #define	PMAP_STAT_INCR(s, v)	atomic_add_long((unsigned long *)(&(s)), (v))
 #define	PMAP_STAT_DECR(s, v)	atomic_add_long((unsigned long *)(&(s)), -(v))
 /*
  * pmap_init_cpu:
+ *
  *	Initilize pmap data in the cpu_info.
  */
 void
 pmap_init_cpu(struct cpu_info * const ci)
+{
 	pmap_t const pmap = pmap_kernel();
 	/* All CPUs start out using the kernel pmap. */
 	atomic_or_ulong(&pmap->pm_cpus, 1UL << ci->ci_cpuid);
 	pmap_reference(pmap);
 	ci->ci_pmap = pmap;
 	/* Initialize ASN allocation logic. */
 	ci->ci_next_asn = PMAP_ASN_FIRST_USER;
 	ci->ci_asn_gen = PMAP_ASNGEN_INITIAL;
+}
 /*
  * pmap_bootstrap:
+ *
  *	Bootstrap the system to run with virtual memory.
+ *
  *	Note: no locking is necessary in this function.
  */
 void
 pmap_bootstrap(paddr_t ptaddr, u_int maxasn, u_long ncpuids)
+{
 	vsize_t lev2mapsize, lev3mapsize;
 	pt_entry_t *lev2map, *lev3map;
 	pt_entry_t pte;
 	vsize_t bufsz;
 	struct pcb *pcb;
 	int i;
 #ifdef DEBUG
 	if (pmapdebug & (PDB_FOLLOW|PDB_BOOTSTRAP))
 		printf("pmap_bootstrap(0x%lx, %u)\n", ptaddr, maxasn);
 #endif
 	/*
 	 * Compute the number of pages kmem_arena will have.
 	 */
 	kmeminit_nkmempages();
 	/*
 	 * Figure out how many initial PTE's are necessary to map the
 	 * kernel.  We also reserve space for kmem_alloc_pageable()
 	 * for vm_fork().
 	 */
 	/* Get size of buffer cache and set an upper limit */
 	bufsz = buf_memcalc();
 	buf_setvalimit(bufsz);
 	lev3mapsize =
 		(VM_PHYS_SIZE + (ubc_nwins << ubc_winshift) +
 		 bufsz + 16 * NCARGS + pager_map_size) / PAGE_SIZE +
 		(maxproc * UPAGES) + nkmempages;
 	lev3mapsize = roundup(lev3mapsize, NPTEPG);
 	/*
 	 * Initialize `FYI' variables.  Note we're relying on
 	 * the fact that BSEARCH sorts the vm_physmem[] array
 	 * for us.
 	 */
 	avail_start = ptoa(uvm_physseg_get_avail_start(uvm_physseg_get_first()));
 	avail_end = ptoa(uvm_physseg_get_avail_end(uvm_physseg_get_last()));
 	virtual_end = VM_MIN_KERNEL_ADDRESS + lev3mapsize * PAGE_SIZE;
 #if 0
 	printf("avail_start = 0x%lx\n", avail_start);
 	printf("avail_end = 0x%lx\n", avail_end);
 	printf("virtual_end = 0x%lx\n", virtual_end);
 #endif
 	/*
 	 * Allocate a level 1 PTE table for the kernel.
 	 * This is always one page long.
 	 * IF THIS IS NOT A MULTIPLE OF PAGE_SIZE, ALL WILL GO TO HELL.
 	 */
 	kernel_lev1map = (pt_entry_t *)
 	    uvm_pageboot_alloc(sizeof(pt_entry_t) * NPTEPG);
 	/*
 	 * Allocate a level 2 PTE table for the kernel.
 	 * These must map all of the level3 PTEs.
 	 * IF THIS IS NOT A MULTIPLE OF PAGE_SIZE, ALL WILL GO TO HELL.
 	 */
 	lev2mapsize = roundup(howmany(lev3mapsize, NPTEPG), NPTEPG);
 	lev2map = (pt_entry_t *)
 	    uvm_pageboot_alloc(sizeof(pt_entry_t) * lev2mapsize);
 	/*
 	 * Allocate a level 3 PTE table for the kernel.
 	 * Contains lev3mapsize PTEs.
 	 */
 	lev3map = (pt_entry_t *)
 	    uvm_pageboot_alloc(sizeof(pt_entry_t) * lev3mapsize);
 	/*
 	 * Set up level 1 page table
 	 */
 	/* Map all of the level 2 pte pages */
 	for (i = 0; i < howmany(lev2mapsize, NPTEPG); i++) {
 		pte = (ALPHA_K0SEG_TO_PHYS(((vaddr_t)lev2map) +
 		    (i*PAGE_SIZE)) >> PGSHIFT) << PG_SHIFT;
 		pte |= PG_V | PG_ASM | PG_KRE | PG_KWE | PG_WIRED;
 		kernel_lev1map[l1pte_index(VM_MIN_KERNEL_ADDRESS +
 		    (i*PAGE_SIZE*NPTEPG*NPTEPG))] = pte;
+	}
 	/* Map the virtual page table */
 	pte = (ALPHA_K0SEG_TO_PHYS((vaddr_t)kernel_lev1map) >> PGSHIFT)
 	    << PG_SHIFT;
 	pte |= PG_V | PG_KRE | PG_KWE; /* NOTE NO ASM */
 	kernel_lev1map[l1pte_index(VPTBASE)] = pte;
 	VPT = (pt_entry_t *)VPTBASE;
 	/*
 	 * Set up level 2 page table.
 	 */
 	/* Map all of the level 3 pte pages */
 	for (i = 0; i < howmany(lev3mapsize, NPTEPG); i++) {
 		pte = (ALPHA_K0SEG_TO_PHYS(((vaddr_t)lev3map) +
 		    (i*PAGE_SIZE)) >> PGSHIFT) << PG_SHIFT;
 		pte |= PG_V | PG_ASM | PG_KRE | PG_KWE | PG_WIRED;
 		lev2map[l2pte_index(VM_MIN_KERNEL_ADDRESS+
 		    (i*PAGE_SIZE*NPTEPG))] = pte;
+	}
 	/* Initialize the pmap_growkernel_lock. */
 	rw_init(&pmap_growkernel_lock);
 	/*
 	 * Set up level three page table (lev3map)
 	 */
 	/* Nothing to do; it's already zero'd */
 	/*
 	 * Initialize the pmap pools and list.
 	 */
 	pmap_ncpuids = ncpuids;
 	pool_cache_bootstrap(&pmap_pmap_cache, PMAP_SIZEOF(pmap_ncpuids),
 	    COHERENCY_UNIT, 0, 0, "pmap", NULL, IPL_NONE, NULL, NULL, NULL);
 	pool_cache_bootstrap(&pmap_l1pt_cache, PAGE_SIZE, 0, 0, 0, "pmapl1pt",
 	    &pmap_l1pt_allocator, IPL_NONE, pmap_l1pt_ctor, NULL, NULL);
 	pool_cache_bootstrap(&pmap_pv_cache, sizeof(struct pv_entry), 0, 0,
 	    PR_LARGECACHE, "pmappv", &pmap_pv_page_allocator, IPL_NONE, NULL,
 	    NULL, NULL);
 	TAILQ_INIT(&pmap_all_pmaps);
 	/* Initialize the ASN logic.  See also pmap_init_cpu(). */
 	pmap_max_asn = maxasn;
 	/*
 	 * Initialize the locks.
 	 */
 	rw_init(&pmap_main_lock);
 	mutex_init(&pmap_all_pmaps_lock, MUTEX_DEFAULT, IPL_NONE);
 	for (i = 0; i < __arraycount(pmap_pvh_locks); i++) {
 		mutex_init(&pmap_pvh_locks[i].lock, MUTEX_DEFAULT, IPL_NONE);
+	}
 	for (i = 0; i < __arraycount(pmap_pvh_locks); i++) {
 		mutex_init(&pmap_pmap_locks[i].locks.lock,
 		    MUTEX_DEFAULT, IPL_NONE);
 		mutex_init(&pmap_pmap_locks[i].locks.activation_lock,
 		    MUTEX_SPIN, IPL_SCHED);
+	}
 	/*
 	 * This must block any interrupt from which a TLB shootdown
 	 * could be issued, but must NOT block IPIs.
 	 */
 	mutex_init(&tlb_lock, MUTEX_SPIN, IPL_VM);
 	/*
 	 * Initialize kernel pmap.  Note that all kernel mappings
 	 * have PG_ASM set, so the ASN doesn't really matter for
 	 * the kernel pmap.  Also, since the kernel pmap always
 	 * references kernel_lev1map, it always has an invalid ASN
 	 * generation.
 	 */
 	memset(pmap_kernel(), 0, sizeof(struct pmap));
 	LIST_INIT(&pmap_kernel()->pm_ptpages);
 	LIST_INIT(&pmap_kernel()->pm_pvents);
 	atomic_store_relaxed(&pmap_kernel()->pm_count, 1);
 	/* Kernel pmap does not have per-CPU info. */
 	TAILQ_INSERT_TAIL(&pmap_all_pmaps, pmap_kernel(), pm_list);
 	/*
 	 * Set up lwp0's PCB such that the ptbr points to the right place
 	 * and has the kernel pmap's (really unused) ASN.
 	 */
 	pcb = lwp_getpcb(&lwp0);
 	pcb->pcb_hw.apcb_ptbr =
 	    ALPHA_K0SEG_TO_PHYS((vaddr_t)kernel_lev1map) >> PGSHIFT;
 	pcb->pcb_hw.apcb_asn = PMAP_ASN_KERNEL;
 	struct cpu_info * const ci = curcpu();
 	pmap_init_cpu(ci);
+}
 /*
  * pmap_virtual_space:		[ INTERFACE ]
+ *
  *	Define the initial bounds of the kernel virtual address space.
  */
 void
 pmap_virtual_space(vaddr_t *vstartp, vaddr_t *vendp)
+{
 	*vstartp = VM_MIN_KERNEL_ADDRESS;	/* kernel is in K0SEG */
 	*vendp = VM_MAX_KERNEL_ADDRESS;		/* we use pmap_growkernel */
+}
 /*
  * pmap_steal_memory:		[ INTERFACE ]
+ *
  *	Bootstrap memory allocator (alternative to vm_bootstrap_steal_memory()).
  *	This function allows for early dynamic memory allocation until the
  *	virtual memory system has been bootstrapped.  After that point, either
  *	kmem_alloc or malloc should be used.  This function works by stealing
  *	pages from the (to be) managed page pool, then implicitly mapping the
  *	pages (by using their k0seg addresses) and zeroing them.
+ *
  *	It may be used once the physical memory segments have been pre-loaded
  *	into the vm_physmem[] array.  Early memory allocation MUST use this
  *	interface!  This cannot be used after vm_page_startup(), and will
  *	generate a panic if tried.
+ *
  *	Note that this memory will never be freed, and in essence it is wired
  *	down.
+ *
  *	We must adjust *vstartp and/or *vendp iff we use address space
  *	from the kernel virtual address range defined by pmap_virtual_space().
+ *
  *	Note: no locking is necessary in this function.
  */
 vaddr_t
 pmap_steal_memory(vsize_t size, vaddr_t *vstartp, vaddr_t *vendp)
+{
 	int npgs;
 	vaddr_t va;
 	paddr_t pa;
 	uvm_physseg_t bank;
 	size = round_page(size);
 	npgs = atop(size);
 #if 0
 	printf("PSM: size 0x%lx (npgs 0x%x)\n", size, npgs);
 #endif
 	for (bank = uvm_physseg_get_first();
 	     uvm_physseg_valid_p(bank);
 	     bank = uvm_physseg_get_next(bank)) {
 		if (uvm.page_init_done == true)
 			panic("pmap_steal_memory: called _after_ bootstrap");
 #if 0
 		printf("     bank %d: avail_start 0x%"PRIxPADDR", start 0x%"PRIxPADDR", "
 		    "avail_end 0x%"PRIxPADDR"\n", bank, uvm_physseg_get_avail_start(bank),
 		    uvm_physseg_get_start(bank), uvm_physseg_get_avail_end(bank));
 #endif
 		if (uvm_physseg_get_avail_start(bank) != uvm_physseg_get_start(bank) ||
 		    uvm_physseg_get_avail_start(bank) >= uvm_physseg_get_avail_end(bank))
 			continue;
 #if 0
 		printf("             avail_end - avail_start = 0x%"PRIxPADDR"\n",
 		    uvm_physseg_get_avail_end(bank) - uvm_physseg_get_avail_start(bank));
 #endif
 		if (uvm_physseg_get_avail_end(bank) - uvm_physseg_get_avail_start(bank)
 		    < npgs)
 			continue;
 		/*
 		 * There are enough pages here; steal them!
 		 */
 		pa = ptoa(uvm_physseg_get_start(bank));
 		uvm_physseg_unplug(atop(pa), npgs);
 		va = ALPHA_PHYS_TO_K0SEG(pa);
 		memset((void *)va, 0, size);
 		pmap_pages_stolen += npgs;
 		return (va);
+	}
 	/*
 	 * If we got here, this was no memory left.
 	 */
 	panic("pmap_steal_memory: no memory to steal");
+}
 /*
  * pmap_init:			[ INTERFACE ]
+ *
  *	Initialize the pmap module.  Called by vm_init(), to initialize any
  *	structures that the pmap system needs to map virtual memory.
+ *
  *	Note: no locking is necessary in this function.
  */
 void
 pmap_init(void)
+{
 #ifdef DEBUG
 	if (pmapdebug & PDB_FOLLOW)
 	        printf("pmap_init()\n");
 #endif
 	/* initialize protection array */
 	alpha_protection_init();
 	/* Initialize TLB handling. */
 	pmap_tlb_init();
 	/*
 	 * Set a low water mark on the pv_entry pool, so that we are
 	 * more likely to have these around even in extreme memory
 	 * starvation.
 	 */
 	pool_cache_setlowat(&pmap_pv_cache, pmap_pv_lowat);
 	/*
 	 * Now it is safe to enable pv entry recording.
 	 */
 	pmap_initialized = true;
 #if 0
 	for (uvm_physseg_t bank = uvm_physseg_get_first();
 	    uvm_physseg_valid_p(bank);
 	    bank = uvm_physseg_get_next(bank)) {
 		printf("bank %d\n", bank);
 		printf("\tstart = 0x%lx\n", ptoa(uvm_physseg_get_start(bank)));
 		printf("\tend = 0x%lx\n", ptoa(uvm_physseg_get_end(bank)));
 		printf("\tavail_start = 0x%lx\n",
 		    ptoa(uvm_physseg_get_avail_start(bank)));
 		printf("\tavail_end = 0x%lx\n",
 		    ptoa(uvm_physseg_get_avail_end(bank)));
+	}
 #endif
+}
 /*
  * pmap_create:			[ INTERFACE ]
+ *
  *	Create and return a physical map.
+ *
  *	Note: no locking is necessary in this function.
  */
 pmap_t
 pmap_create(void)
+{
 	pmap_t pmap;
 	pt_entry_t *lev1map;
 	int i;
 #ifdef DEBUG
 	if (pmapdebug & (PDB_FOLLOW|PDB_CREATE))
 		printf("pmap_create()\n");
 #endif
 	pmap = pool_cache_get(&pmap_pmap_cache, PR_WAITOK);
 	memset(pmap, 0, sizeof(*pmap));
 	LIST_INIT(&pmap->pm_ptpages);
 	LIST_INIT(&pmap->pm_pvents);
 	atomic_store_relaxed(&pmap->pm_count, 1);
  try_again:
 	rw_enter(&pmap_growkernel_lock, RW_READER);
 	lev1map = pool_cache_get(&pmap_l1pt_cache, PR_NOWAIT);
 	if (__predict_false(lev1map == NULL)) {
 		rw_exit(&pmap_growkernel_lock);
 		(void) kpause("pmap_create", false, hz >> 2, NULL);
 		goto try_again;
+	}
 	/*
 	 * There are only kernel mappings at this point; give the pmap
 	 * the kernel ASN.  This will be initialized to correct values
 	 * when the pmap is activated.
+	 *
 	 * We stash a pointer to the pmap's lev1map in each CPU's
 	 * private data.  It remains constant for the life of the
 	 * pmap, and gives us more room in the shared pmap structure.
 	 */
 	for (i = 0; i < pmap_ncpuids; i++) {
 		pmap->pm_percpu[i].pmc_asn = PMAP_ASN_KERNEL;
 		pmap->pm_percpu[i].pmc_asngen = PMAP_ASNGEN_INVALID;
 		pmap->pm_percpu[i].pmc_lev1map = lev1map;
+	}
 	mutex_enter(&pmap_all_pmaps_lock);
 	TAILQ_INSERT_TAIL(&pmap_all_pmaps, pmap, pm_list);
 	mutex_exit(&pmap_all_pmaps_lock);
 	rw_exit(&pmap_growkernel_lock);
 	return (pmap);
+}
 /*
  * pmap_destroy:		[ INTERFACE ]
+ *
  *	Drop the reference count on the specified pmap, releasing
  *	all resources if the reference count drops to zero.
  */
 void
 pmap_destroy(pmap_t pmap)
+{
 #ifdef DEBUG
 	if (pmapdebug & PDB_FOLLOW)
 		printf("pmap_destroy(%p)\n", pmap);
 #endif
 	PMAP_MP(membar_exit());
 	KASSERT(atomic_load_relaxed(&pmap->pm_count) > 0);
 	if (atomic_dec_uint_nv(&pmap->pm_count) > 0)
 		return;
 	pt_entry_t *lev1map = pmap_lev1map(pmap);
 	int i;
 	rw_enter(&pmap_growkernel_lock, RW_READER);
 	/*
 	 * Remove it from the global list of all pmaps.
 	 */
 	mutex_enter(&pmap_all_pmaps_lock);
 	TAILQ_REMOVE(&pmap_all_pmaps, pmap, pm_list);
 	mutex_exit(&pmap_all_pmaps_lock);
 	pool_cache_put(&pmap_l1pt_cache, lev1map);
 #ifdef DIAGNOSTIC
 	for (i = 0; i < pmap_ncpuids; i++) {
 		pmap->pm_percpu[i].pmc_lev1map = (pt_entry_t *)0xdeadbeefUL;
+	}
 #endif /* DIAGNOSTIC */
 	rw_exit(&pmap_growkernel_lock);
 	pool_cache_put(&pmap_pmap_cache, pmap);
+}
 /*
  * pmap_reference:		[ INTERFACE ]
+ *
  *	Add a reference to the specified pmap.
  */
 void
 pmap_reference(pmap_t pmap)
+{
 	unsigned int newcount __diagused;
 #ifdef DEBUG
 	if (pmapdebug & PDB_FOLLOW)
 		printf("pmap_reference(%p)\n", pmap);
 #endif
 	newcount = atomic_inc_uint_nv(&pmap->pm_count);
 	KASSERT(newcount != 0);
 	PMAP_MP(membar_enter());
+}
 /*
  * pmap_remove:			[ INTERFACE ]
+ *
  *	Remove the given range of addresses from the specified map.
+ *
  *	It is assumed that the start and end are properly
  *	rounded to the page size.
  */
 static void
 pmap_remove_internal(pmap_t pmap, vaddr_t sva, vaddr_t eva,
     struct pmap_tlb_context * const tlbctx)
+{
 	pt_entry_t *l1pte, *l2pte, *l3pte;
 	pt_entry_t *saved_l2pte, *saved_l3pte;
 	vaddr_t l1eva, l2eva, l3vptva;
 	pt_entry_t pte_bits;
 #ifdef DEBUG
 	if (pmapdebug & (PDB_FOLLOW|PDB_REMOVE|PDB_PROTECT))
 		printf("pmap_remove(%p, %lx, %lx)\n", pmap, sva, eva);
 #endif
 	/*
 	 * If this is the kernel pmap, we can use a faster method
 	 * for accessing the PTEs (since the PT pages are always
 	 * resident).
+	 *
 	 * Note that this routine should NEVER be called from an
 	 * interrupt context; pmap_kremove() is used for that.
 	 */
 	if (pmap == pmap_kernel()) {
 		PMAP_MAP_TO_HEAD_LOCK();
 		PMAP_LOCK(pmap);
 		while (sva < eva) {
 			l3pte = PMAP_KERNEL_PTE(sva);
 			if (pmap_pte_v(l3pte)) {
 				pte_bits = pmap_remove_mapping(pmap, sva,
 				    l3pte, true, NULL, tlbctx);
 				pmap_tlb_shootdown(pmap, sva, pte_bits,
 				    tlbctx);
+			}
 			sva += PAGE_SIZE;
+		}
 		PMAP_MAP_TO_HEAD_UNLOCK();
 		PMAP_UNLOCK(pmap);
 		pmap_tlb_shootnow(tlbctx);
 		/* kernel PT pages are never freed. */
 		KASSERT(LIST_EMPTY(&tlbctx->t_freeptq));
 		TLB_COUNT(reason_remove_kernel);
 		return;
+	}
 	pt_entry_t * const lev1map = pmap_lev1map(pmap);
 	KASSERT(sva < VM_MAXUSER_ADDRESS);
 	KASSERT(eva <= VM_MAXUSER_ADDRESS);
 	KASSERT(lev1map != kernel_lev1map);
 	PMAP_MAP_TO_HEAD_LOCK();
 	PMAP_LOCK(pmap);
 	l1pte = pmap_l1pte(lev1map, sva);
 	for (; sva < eva; sva = l1eva, l1pte++) {
 		l1eva = alpha_trunc_l1seg(sva) + ALPHA_L1SEG_SIZE;
 		if (pmap_pte_v(l1pte)) {
 			saved_l2pte = l2pte = pmap_l2pte(lev1map, sva, l1pte);
 			/*
 			 * Add a reference to the L2 table so it won't
 			 * get removed from under us.
 			 */
 			pmap_physpage_addref(saved_l2pte);
 			for (; sva < l1eva && sva < eva; sva = l2eva, l2pte++) {
 				l2eva =
 				    alpha_trunc_l2seg(sva) + ALPHA_L2SEG_SIZE;
 				if (pmap_pte_v(l2pte)) {
 					saved_l3pte = l3pte =
 					    pmap_l3pte(lev1map, sva, l2pte);
 					/*
 					 * Add a reference to the L3 table so
 					 * it won't get removed from under us.
 					 */
 					pmap_physpage_addref(saved_l3pte);
 					/*
 					 * Remember this sva; if the L3 table
 					 * gets removed, we need to invalidate
 					 * the VPT TLB entry for it.
 					 */
 					l3vptva = sva;
 					for (; sva < l2eva && sva < eva;
 					     sva += PAGE_SIZE, l3pte++) {
 						if (!pmap_pte_v(l3pte)) {
 							continue;
+						}
 						pte_bits =
 						    pmap_remove_mapping(
 							pmap, sva,
 							l3pte, true,
 							NULL, tlbctx);
 						pmap_tlb_shootdown(pmap,
 						    sva, pte_bits, tlbctx);
+					}
 					/*
 					 * Remove the reference to the L3
 					 * table that we added above.  This
 					 * may free the L3 table.
 					 */
 					pmap_l3pt_delref(pmap, l3vptva,
 					    saved_l3pte, tlbctx);
+				}
+			}
 			/*
 			 * Remove the reference to the L2 table that we
 			 * added above.  This may free the L2 table.
 			 */
 			pmap_l2pt_delref(pmap, l1pte, saved_l2pte, tlbctx);
+		}
+	}
 	PMAP_MAP_TO_HEAD_UNLOCK();
 	PMAP_UNLOCK(pmap);
 	pmap_tlb_shootnow(tlbctx);
 	pmap_tlb_ptpage_drain(tlbctx);
 	TLB_COUNT(reason_remove_user);
+}
 void
 pmap_remove(pmap_t pmap, vaddr_t sva, vaddr_t eva)
+{
 	struct pmap_tlb_context tlbctx;
 	pmap_tlb_context_init(&tlbctx, 0);
 	pmap_remove_internal(pmap, sva, eva, &tlbctx);
+}
 /*
  * pmap_page_protect:		[ INTERFACE ]
+ *
  *	Lower the permission for all mappings to a given page to
  *	the permissions specified.
  */
 void
 pmap_page_protect(struct vm_page *pg, vm_prot_t prot)
+{
 	pv_entry_t pv, nextpv;
 	pt_entry_t opte;
 	kmutex_t *lock;
 	struct pmap_tlb_context tlbctx;
 #ifdef DEBUG
 	paddr_t pa = VM_PAGE_TO_PHYS(pg);
 	if ((pmapdebug & (PDB_FOLLOW|PDB_PROTECT)) ||
 	    (prot == VM_PROT_NONE && (pmapdebug & PDB_REMOVE)))
 		printf("pmap_page_protect(%p, %x)\n", pg, prot);
 #endif
 	pmap_tlb_context_init(&tlbctx, TLB_CTX_F_PV);
 	switch (prot) {
 	case VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE:
 	case VM_PROT_READ|VM_PROT_WRITE:
 		return;
 	/* copy_on_write */
 	case VM_PROT_READ|VM_PROT_EXECUTE:
 	case VM_PROT_READ:
 		PMAP_HEAD_TO_MAP_LOCK();
 		lock = pmap_pvh_lock(pg);
 		mutex_enter(lock);
 		for (pv = VM_MDPAGE_PVS(pg); pv != NULL; pv = pv->pv_next) {
 			PMAP_LOCK(pv->pv_pmap);
 			opte = atomic_load_relaxed(pv->pv_pte);
 			if (opte & (PG_KWE | PG_UWE)) {
 				atomic_store_relaxed(pv->pv_pte,
 				    opte & ~(PG_KWE | PG_UWE));
 				pmap_tlb_shootdown_pv(pv->pv_pmap, pv->pv_va,
 				    opte, &tlbctx);
+			}
 			PMAP_UNLOCK(pv->pv_pmap);
+		}
 		mutex_exit(lock);
 		PMAP_HEAD_TO_MAP_UNLOCK();
 		pmap_tlb_shootnow(&tlbctx);
 		TLB_COUNT(reason_page_protect_read);
 		return;
 	/* remove_all */
 	default:
 		break;
+	}
 	PMAP_HEAD_TO_MAP_LOCK();
 	lock = pmap_pvh_lock(pg);
 	mutex_enter(lock);
 	for (pv = VM_MDPAGE_PVS(pg); pv != NULL; pv = nextpv) {
 		pt_entry_t pte_bits;
 		pmap_t pmap;
 		vaddr_t va;
 		nextpv = pv->pv_next;
 		PMAP_LOCK(pv->pv_pmap);
 		pmap = pv->pv_pmap;
 		va = pv->pv_va;
 		pte_bits = pmap_remove_mapping(pmap, va, pv->pv_pte,
 		    false, NULL, &tlbctx);
 		pmap_tlb_shootdown_pv(pmap, va, pte_bits, &tlbctx);
 		PMAP_UNLOCK(pv->pv_pmap);
+	}
 	mutex_exit(lock);
 	PMAP_HEAD_TO_MAP_UNLOCK();
 	pmap_tlb_shootnow(&tlbctx);
 	pmap_tlb_ptpage_drain(&tlbctx);
 	TLB_COUNT(reason_page_protect_none);
+}
 /*
  * pmap_protect:		[ INTERFACE ]
+ *
  *	Set the physical protection on the specified range of this map
  *	as requested.
  */
 void
 pmap_protect(pmap_t pmap, vaddr_t sva, vaddr_t eva, vm_prot_t prot)
+{
 	pt_entry_t *l1pte, *l2pte, *l3pte, opte;
 	vaddr_t l1eva, l2eva;
 	struct pmap_tlb_context tlbctx;
 #ifdef DEBUG
 	if (pmapdebug & (PDB_FOLLOW|PDB_PROTECT))
 		printf("pmap_protect(%p, %lx, %lx, %x)\n",
 		    pmap, sva, eva, prot);
 #endif
 	pmap_tlb_context_init(&tlbctx, 0);
 	if ((prot & VM_PROT_READ) == VM_PROT_NONE) {
 		pmap_remove_internal(pmap, sva, eva, &tlbctx);
 		return;
+	}
 	const pt_entry_t bits = pte_prot(pmap, prot);
 	pt_entry_t * const lev1map = pmap_lev1map(pmap);
 	PMAP_LOCK(pmap);
 	l1pte = pmap_l1pte(lev1map, sva);
 	for (; sva < eva; sva = l1eva, l1pte++) {
 		l1eva = alpha_trunc_l1seg(sva) + ALPHA_L1SEG_SIZE;
 		if (pmap_pte_v(l1pte)) {
 			l2pte = pmap_l2pte(lev1map, sva, l1pte);
 			for (; sva < l1eva && sva < eva; sva = l2eva, l2pte++) {
 				l2eva =
 				    alpha_trunc_l2seg(sva) + ALPHA_L2SEG_SIZE;
 				if (pmap_pte_v(l2pte)) {
 					l3pte = pmap_l3pte(lev1map, sva, l2pte);
 					for (; sva < l2eva && sva < eva;
 					     sva += PAGE_SIZE, l3pte++) {
 						if (pmap_pte_v(l3pte) &&
 						    pmap_pte_prot_chg(l3pte,
 								      bits)) {
 							opte = atomic_load_relaxed(l3pte);
 							pmap_pte_set_prot(l3pte,
 							   bits);
 							pmap_tlb_shootdown(pmap,
 							    sva, opte, &tlbctx);
+						}
+					}
+				}
+			}
+		}
+	}
 	PMAP_UNLOCK(pmap);
 	pmap_tlb_shootnow(&tlbctx);
 	TLB_COUNT(reason_protect);
+}
 /*
  * pmap_enter_tlb_shootdown:
+ *
  *	Carry out a TLB shootdown on behalf of a pmap_enter()
  *	or a pmap_kenter_pa().  This is factored out separately
  *	because we expect it to be not a common case.
  */
 static void __noinline
 pmap_enter_tlb_shootdown(pmap_t const pmap, vaddr_t const va,
     pt_entry_t const pte_bits, bool locked)
+{
 	struct pmap_tlb_context tlbctx;
 	pmap_tlb_context_init(&tlbctx, 0);
 	pmap_tlb_shootdown(pmap, va, pte_bits, &tlbctx);
 	if (locked) {
 		PMAP_UNLOCK(pmap);
+	}
 	pmap_tlb_shootnow(&tlbctx);
+}
 /*
  * pmap_enter_l2pt_delref:
+ *
  *	Release a reference on an L2 PT page for pmap_enter().
  *	This is factored out separately becacause we expect it
  *	to be a rare case.
  */
 static void __noinline
 pmap_enter_l2pt_delref(pmap_t const pmap, pt_entry_t * const l1pte,
     pt_entry_t * const l2pte)
+{
 	struct pmap_tlb_context tlbctx;
 	/*
 	 * PALcode may have tried to service a TLB miss with
 	 * this L2 PTE, so we need to make sure we don't actully
 	 * free the PT page untl we've shot down any TLB entries
 	 * for this VPT index.
 	 */
 	pmap_tlb_context_init(&tlbctx, 0);
 	pmap_l2pt_delref(pmap, l1pte, l2pte, &tlbctx);
 	PMAP_UNLOCK(pmap);
 	pmap_tlb_shootnow(&tlbctx);
 	pmap_tlb_ptpage_drain(&tlbctx);
 	TLB_COUNT(reason_enter_l2pt_delref);
+}
 /*
  * pmap_enter_l3pt_delref:
+ *
  *	Release a reference on an L3 PT page for pmap_enter().
  *	This is factored out separately becacause we expect it
  *	to be a rare case.
  */
 static void __noinline
 pmap_enter_l3pt_delref(pmap_t const pmap, vaddr_t const va,
     pt_entry_t * const pte)
+{
 	struct pmap_tlb_context tlbctx;
 	/*
 	 * PALcode may have tried to service a TLB miss with
 	 * this PTE, so we need to make sure we don't actully
 	 * free the PT page untl we've shot down any TLB entries
 	 * for this VPT index.
 	 */
 	pmap_tlb_context_init(&tlbctx, 0);
 	pmap_l3pt_delref(pmap, va, pte, &tlbctx);
 	PMAP_UNLOCK(pmap);
 	pmap_tlb_shootnow(&tlbctx);
 	pmap_tlb_ptpage_drain(&tlbctx);
 	TLB_COUNT(reason_enter_l3pt_delref);
+}
 /*
  * pmap_enter:			[ INTERFACE ]
+ *
  *	Insert the given physical page (p) at
  *	the specified virtual address (v) in the
  *	target physical map with the protection requested.
+ *
  *	If specified, the page will be wired down, meaning
  *	that the related pte can not be reclaimed.
+ *
  *	Note:  This is the only routine which MAY NOT lazy-evaluate
  *	or lose information.  That is, this routine must actually
  *	insert this page into the given map NOW.
  */
 int
 pmap_enter(pmap_t pmap, vaddr_t va, paddr_t pa, vm_prot_t prot, u_int flags)
+{
 	pt_entry_t *pte, npte, opte;
 	pv_entry_t opv = NULL;
 	paddr_t opa;
 	bool tflush = false;
 	int error = 0;
 	kmutex_t *lock;
 #ifdef DEBUG
 	if (pmapdebug & (PDB_FOLLOW|PDB_ENTER))
 		printf("pmap_enter(%p, %lx, %lx, %x, %x)\n",
 		       pmap, va, pa, prot, flags);
 #endif
 	struct vm_page * const pg = PHYS_TO_VM_PAGE(pa);
 	const bool wired = (flags & PMAP_WIRED) != 0;
 	PMAP_MAP_TO_HEAD_LOCK();
 	PMAP_LOCK(pmap);
 	if (pmap == pmap_kernel()) {
 		KASSERT(va >= VM_MIN_KERNEL_ADDRESS);
 		pte = PMAP_KERNEL_PTE(va);
 	} else {
 		pt_entry_t *l1pte, *l2pte;
 		pt_entry_t * const lev1map = pmap_lev1map(pmap);
 		KASSERT(va < VM_MAXUSER_ADDRESS);
 		KASSERT(lev1map != kernel_lev1map);
 		/*
 		 * Check to see if the level 1 PTE is valid, and
 		 * allocate a new level 2 page table page if it's not.
 		 * A reference will be added to the level 2 table when
 		 * the level 3 table is created.
 		 */
 		l1pte = pmap_l1pte(lev1map, va);
 		if (pmap_pte_v(l1pte) == 0) {
 			pmap_physpage_addref(l1pte);
 			error = pmap_ptpage_alloc(pmap, l1pte, PGU_L2PT);
 			if (error) {
 				pmap_l1pt_delref(pmap, l1pte);
 				if (flags & PMAP_CANFAIL)
 					goto out;
 				panic("pmap_enter: unable to create L2 PT "
 				    "page");
+			}
 #ifdef DEBUG
 			if (pmapdebug & PDB_PTPAGE)
 				printf("pmap_enter: new level 2 table at "
 				    "0x%lx\n", pmap_pte_pa(l1pte));
 #endif
+		}
 		/*
 		 * Check to see if the level 2 PTE is valid, and
 		 * allocate a new level 3 page table page if it's not.
 		 * A reference will be added to the level 3 table when
 		 * the mapping is validated.
 		 */
 		l2pte = pmap_l2pte(lev1map, va, l1pte);
 		if (pmap_pte_v(l2pte) == 0) {
 			pmap_physpage_addref(l2pte);
 			error = pmap_ptpage_alloc(pmap, l2pte, PGU_L3PT);
 			if (error) {
 				/* unlocks pmap */
 				pmap_enter_l2pt_delref(pmap, l1pte, l2pte);
 				if (flags & PMAP_CANFAIL) {
 					PMAP_LOCK(pmap);
 					goto out;
+				}
 				panic("pmap_enter: unable to create L3 PT "
 				    "page");
+			}
 #ifdef DEBUG
 			if (pmapdebug & PDB_PTPAGE)
 				printf("pmap_enter: new level 3 table at "
 				    "0x%lx\n", pmap_pte_pa(l2pte));
 #endif
+		}
 		/*
 		 * Get the PTE that will map the page.
 		 */
 		pte = pmap_l3pte(lev1map, va, l2pte);
+	}
 	/* Remember all of the old PTE; used for TBI check later. */
 	opte = atomic_load_relaxed(pte);
 	/*
 	 * Check to see if the old mapping is valid.  If not, validate the
 	 * new one immediately.
 	 */
 	if ((opte & PG_V) == 0) {
 		/* No TLB invalidatons needed for new mappings. */
 		if (pmap != pmap_kernel()) {
 			/*
 			 * New mappings gain a reference on the level 3
 			 * table.
 			 */
 			pmap_physpage_addref(pte);
+		}
 		goto validate_enterpv;
+	}
 	opa = pmap_pte_pa(pte);
 	if (opa == pa) {
 		/*
 		 * Mapping has not changed; must be a protection or
 		 * wiring change.
 		 */
 		if (pmap_pte_w_chg(pte, wired ? PG_WIRED : 0)) {
 #ifdef DEBUG
 			if (pmapdebug & PDB_ENTER)
 				printf("pmap_enter: wiring change -> %d\n",
 				    wired);
 #endif
 			/* Adjust the wiring count. */
 			if (wired)
 				PMAP_STAT_INCR(pmap->pm_stats.wired_count, 1);
 			else
 				PMAP_STAT_DECR(pmap->pm_stats.wired_count, 1);
+		}
 		/* Set the PTE. */
 		goto validate;
+	}
 	/*
 	 * The mapping has changed.  We need to invalidate the
 	 * old mapping before creating the new one.
 	 */
 #ifdef DEBUG
 	if (pmapdebug & PDB_ENTER)
 		printf("pmap_enter: removing old mapping 0x%lx\n", va);
 #endif
 	if (pmap != pmap_kernel()) {
 		/*
 		 * Gain an extra reference on the level 3 table.
 		 * pmap_remove_mapping() will delete a reference,
 		 * and we don't want the table to be erroneously
 		 * freed.
 		 */
 		pmap_physpage_addref(pte);
+	}
 	/* Already have the bits from opte above. */
 	(void) pmap_remove_mapping(pmap, va, pte, true, &opv, NULL);
  validate_enterpv:
 	/* Enter the mapping into the pv_table if appropriate. */
 	if (pg != NULL) {
 		error = pmap_pv_enter(pmap, pg, va, pte, true, opv);
 		if (error) {
 			/* This can only fail if opv == NULL */
 			KASSERT(opv == NULL);
 			/* unlocks pmap */
 			pmap_enter_l3pt_delref(pmap, va, pte);
 			if (flags & PMAP_CANFAIL) {
 				PMAP_LOCK(pmap);
 				goto out;
+			}
 			panic("pmap_enter: unable to enter mapping in PV "
 			    "table");
+		}
 		opv = NULL;
+	}
 	/* Increment counters. */
 	PMAP_STAT_INCR(pmap->pm_stats.resident_count, 1);
 	if (wired)
 		PMAP_STAT_INCR(pmap->pm_stats.wired_count, 1);
  validate:
 	/* Build the new PTE. */
 	npte = ((pa >> PGSHIFT) << PG_SHIFT) | pte_prot(pmap, prot) | PG_V;
 	if (pg != NULL) {
 		struct vm_page_md * const md = VM_PAGE_TO_MD(pg);
 		uintptr_t attrs = 0;
 		KASSERT(((flags & VM_PROT_ALL) & ~prot) == 0);
 		if (flags & VM_PROT_WRITE)
 			attrs |= (PGA_REFERENCED|PGA_MODIFIED);
 		else if (flags & VM_PROT_ALL)
 			attrs |= PGA_REFERENCED;
 		lock = pmap_pvh_lock(pg);
 		mutex_enter(lock);
 		md->pvh_listx |= attrs;
 		mutex_exit(lock);
 		/* Set up referenced/modified emulation for new mapping. */
 		if ((attrs & PGA_REFERENCED) == 0)
 			npte |= PG_FOR | PG_FOW | PG_FOE;
 		else if ((attrs & PGA_MODIFIED) == 0)
 			npte |= PG_FOW;
 		/*
 		 * Mapping was entered on PV list.
 		 */
 		npte |= PG_PVLIST;
+	}
 	if (wired)
 		npte |= PG_WIRED;
 #ifdef DEBUG
 	if (pmapdebug & PDB_ENTER)
 		printf("pmap_enter: new pte = 0x%lx\n", npte);
 #endif
 	/*
 	 * If the HW / PALcode portion of the new PTE is the same as the
 	 * old PTE, no TBI is necessary.
 	 */
 	if (opte & PG_V) {
 		tflush = PG_PALCODE(opte) != PG_PALCODE(npte);
+	}
 	/* Set the new PTE. */
 	atomic_store_relaxed(pte, npte);
 out:
 	PMAP_MAP_TO_HEAD_UNLOCK();
 	/*
 	 * Invalidate the TLB entry for this VA and any appropriate
 	 * caches.
 	 */
 	if (tflush) {
 		/* unlocks pmap */
 		pmap_enter_tlb_shootdown(pmap, va, opte, true);
 		if (pmap == pmap_kernel()) {
 			TLB_COUNT(reason_enter_kernel);
 		} else {
 			TLB_COUNT(reason_enter_user);
+		}
 	} else {
 		PMAP_UNLOCK(pmap);
+	}
 	if (opv)
 		pmap_pv_free(opv);
 	return error;
+}
 /*
  * pmap_kenter_pa:		[ INTERFACE ]
+ *
  *	Enter a va -> pa mapping into the kernel pmap without any
  *	physical->virtual tracking.
+ *
  *	Note: no locking is necessary in this function.
  */
 void
 pmap_kenter_pa(vaddr_t va, paddr_t pa, vm_prot_t prot, u_int flags)
+{
 	pmap_t const pmap = pmap_kernel();
 #ifdef DEBUG
 	if (pmapdebug & (PDB_FOLLOW|PDB_ENTER))
 		printf("pmap_kenter_pa(%lx, %lx, %x)\n",
 		    va, pa, prot);
 #endif
 	KASSERT(va >= VM_MIN_KERNEL_ADDRESS);
 	pt_entry_t * const pte = PMAP_KERNEL_PTE(va);
 	/* Build the new PTE. */
 	const pt_entry_t npte =
 	    ((pa >> PGSHIFT) << PG_SHIFT) | pte_prot(pmap_kernel(), prot) |
 	    PG_V | PG_WIRED;
 	/* Set the new PTE. */
 	const pt_entry_t opte = atomic_load_relaxed(pte);
 	atomic_store_relaxed(pte, npte);
 	PMAP_STAT_INCR(pmap->pm_stats.resident_count, 1);
 	PMAP_STAT_INCR(pmap->pm_stats.wired_count, 1);
 	/*
 	 * There should not have been anything here, previously,
 	 * so we can skip TLB shootdowns, etc. in the common case.
 	 */
 	if (__predict_false(opte & PG_V)) {
 		const pt_entry_t diff = npte ^ opte;
 		printf_nolog("%s: mapping already present\n", __func__);
 		PMAP_STAT_DECR(pmap->pm_stats.resident_count, 1);
 		if (diff & PG_WIRED)
 			PMAP_STAT_DECR(pmap->pm_stats.wired_count, 1);
 		/* XXX Can't handle this case. */
 		if (diff & PG_PVLIST)
 			panic("pmap_kenter_pa: old mapping was managed");
 		pmap_enter_tlb_shootdown(pmap_kernel(), va, opte, false);
 		TLB_COUNT(reason_kenter);
+	}
+}
 /*
  * pmap_kremove:		[ INTERFACE ]
+ *
  *	Remove a mapping entered with pmap_kenter_pa() starting at va,
  *	for size bytes (assumed to be page rounded).
  */
 void
 pmap_kremove(vaddr_t va, vsize_t size)
+{
 	pt_entry_t *pte, opte;
 	pmap_t const pmap = pmap_kernel();
 	struct pmap_tlb_context tlbctx;
 	int count = 0;
 #ifdef DEBUG
 	if (pmapdebug & (PDB_FOLLOW|PDB_ENTER))
 		printf("pmap_kremove(%lx, %lx)\n",
 		    va, size);
 #endif
 	pmap_tlb_context_init(&tlbctx, 0);
 	KASSERT(va >= VM_MIN_KERNEL_ADDRESS);
 	for (; size != 0; size -= PAGE_SIZE, va += PAGE_SIZE) {
 		pte = PMAP_KERNEL_PTE(va);
 		opte = atomic_load_relaxed(pte);
 		if (opte & PG_V) {
 			KASSERT((opte & PG_PVLIST) == 0);
 			/* Zap the mapping. */
 			atomic_store_relaxed(pte, PG_NV);
 			pmap_tlb_shootdown(pmap, va, opte, &tlbctx);
 			count++;
+		}
+	}
 	/* Update stats. */
 	if (__predict_true(count != 0)) {
 		PMAP_STAT_DECR(pmap->pm_stats.resident_count, count);
 		PMAP_STAT_DECR(pmap->pm_stats.wired_count, count);
+	}
 	pmap_tlb_shootnow(&tlbctx);
 	TLB_COUNT(reason_kremove);
+}
 /*
  * pmap_unwire:			[ INTERFACE ]
+ *
  *	Clear the wired attribute for a map/virtual-address pair.
+ *
  *	The mapping must already exist in the pmap.
  */
 void
 pmap_unwire(pmap_t pmap, vaddr_t va)
+{
 	pt_entry_t *pte;
 #ifdef DEBUG
 	if (pmapdebug & PDB_FOLLOW)
 		printf("pmap_unwire(%p, %lx)\n", pmap, va);
 #endif
 	PMAP_LOCK(pmap);
 	pte = pmap_l3pte(pmap_lev1map(pmap), va, NULL);
 	KASSERT(pte != NULL);
 	KASSERT(pmap_pte_v(pte));
 	/*
 	 * If wiring actually changed (always?) clear the wire bit and
 	 * update the wire count.  Note that wiring is not a hardware
 	 * characteristic so there is no need to invalidate the TLB.
 	 */
 	if (pmap_pte_w_chg(pte, 0)) {
 		pmap_pte_set_w(pte, false);
 		PMAP_STAT_DECR(pmap->pm_stats.wired_count, 1);
+	}
 #ifdef DEBUG
 	else {
 		printf("pmap_unwire: wiring for pmap %p va 0x%lx "
 		    "didn't change!\n", pmap, va);
+	}
 #endif
 	PMAP_UNLOCK(pmap);
+}
 /*
  * pmap_extract:		[ INTERFACE ]
+ *
  *	Extract the physical address associated with the given
  *	pmap/virtual address pair.
  */
 bool
 pmap_extract(pmap_t pmap, vaddr_t va, paddr_t *pap)
+{
 	pt_entry_t *l1pte, *l2pte, *l3pte;
 	paddr_t pa;
 #ifdef DEBUG
 	if (pmapdebug & PDB_FOLLOW)
 		printf("pmap_extract(%p, %lx) -> ", pmap, va);
 #endif
 	/*
 	 * Take a faster path for the kernel pmap.  Avoids locking,
 	 * handles K0SEG.
 	 */
 	if (__predict_true(pmap == pmap_kernel())) {
 		if (__predict_true(vtophys_internal(va, pap))) {
 #ifdef DEBUG
 			if (pmapdebug & PDB_FOLLOW)
 				printf("0x%lx (kernel vtophys)\n", pa);
 #endif
 			return true;
+		}
 #ifdef DEBUG
 		if (pmapdebug & PDB_FOLLOW)
 			printf("failed (kernel vtophys)\n");
 #endif
 		return false;
+	}
 	pt_entry_t * const lev1map = pmap_lev1map(pmap);
 	PMAP_LOCK(pmap);
 	l1pte = pmap_l1pte(lev1map, va);
 	if (pmap_pte_v(l1pte) == 0)
 		goto out;
 	l2pte = pmap_l2pte(lev1map, va, l1pte);
 	if (pmap_pte_v(l2pte) == 0)
 		goto out;
 	l3pte = pmap_l3pte(lev1map, va, l2pte);
 	if (pmap_pte_v(l3pte) == 0)
 		goto out;
 	pa = pmap_pte_pa(l3pte) | (va & PGOFSET);
 	PMAP_UNLOCK(pmap);
 	if (pap != NULL)
 		*pap = pa;
 #ifdef DEBUG
 	if (pmapdebug & PDB_FOLLOW)
 		printf("0x%lx\n", pa);
 #endif
 	return (true);
  out:
 	PMAP_UNLOCK(pmap);
 #ifdef DEBUG
 	if (pmapdebug & PDB_FOLLOW)
 		printf("failed\n");
 #endif
 	return (false);
+}
 /*
  * pmap_copy:			[ INTERFACE ]
+ *
  *	Copy the mapping range specified by src_addr/len
  *	from the source map to the range dst_addr/len
  *	in the destination map.
+ *
  *	This routine is only advisory and need not do anything.
  */
 /* call deleted in <machine/pmap.h> */
 /*
  * pmap_update:			[ INTERFACE ]
+ *
  *	Require that all active physical maps contain no
  *	incorrect entries NOW, by processing any deferred
  *	pmap operations.
  */
 /* call deleted in <machine/pmap.h> */
 /*
  * pmap_activate:		[ INTERFACE ]
+ *
  *	Activate the pmap used by the specified process.  This includes
  *	reloading the MMU context of the current process, and marking
  *	the pmap in use by the processor.
  */
 void
 pmap_activate(struct lwp *l)
+{
 	struct pmap * const pmap = l->l_proc->p_vmspace->vm_map.pmap;
 	struct pcb * const pcb = lwp_getpcb(l);
 #ifdef DEBUG
 	if (pmapdebug & PDB_FOLLOW)
 		printf("pmap_activate(%p)\n", l);
 #endif
 	KASSERT(kpreempt_disabled());
 	struct cpu_info * const ci = curcpu();
 	KASSERT(l == ci->ci_curlwp);
 	u_long const old_ptbr = pcb->pcb_hw.apcb_ptbr;
 	u_int const old_asn = pcb->pcb_hw.apcb_asn;
 	/*
 	 * We hold the activation lock to synchronize with TLB shootdown.
 	 * The kernel pmap does not require those tests because shootdowns
 	 * for the kernel pmap are always sent to all CPUs.
 	 */
 	if (pmap != pmap_kernel()) {
 		PMAP_ACT_LOCK(pmap);
 		pcb->pcb_hw.apcb_asn = pmap_asn_alloc(pmap, ci);
 		atomic_or_ulong(&pmap->pm_cpus, (1UL << ci->ci_cpuid));
 	} else {
 		pcb->pcb_hw.apcb_asn = PMAP_ASN_KERNEL;
+	}
 	pcb->pcb_hw.apcb_ptbr =
 	    ALPHA_K0SEG_TO_PHYS((vaddr_t)pmap_lev1map(pmap)) >> PGSHIFT;
 	/*
 	 * Check to see if the ASN or page table base has changed; if
 	 * so, switch to our own context again so that it will take
 	 * effect.
+	 *
 	 * We test ASN first because it's the most likely value to change.
 	 */
 	if (old_asn != pcb->pcb_hw.apcb_asn ||
 	    old_ptbr != pcb->pcb_hw.apcb_ptbr) {
 		if (old_asn != pcb->pcb_hw.apcb_asn &&
 		    old_ptbr != pcb->pcb_hw.apcb_ptbr) {
 			TLB_COUNT(activate_both_change);
 		} else if (old_asn != pcb->pcb_hw.apcb_asn) {
 			TLB_COUNT(activate_asn_change);
 		} else {
 			TLB_COUNT(activate_ptbr_change);
+		}
 		(void) alpha_pal_swpctx((u_long)l->l_md.md_pcbpaddr);
 		TLB_COUNT(activate_swpctx);
 	} else {
 		TLB_COUNT(activate_skip_swpctx);
+	}
 	pmap_reference(pmap);
 	ci->ci_pmap = pmap;
 	if (pmap != pmap_kernel()) {
 		PMAP_ACT_UNLOCK(pmap);
+	}
+}
 /*
  * pmap_deactivate:		[ INTERFACE ]
+ *
  *	Mark that the pmap used by the specified process is no longer
  *	in use by the processor.
  */
 void
 pmap_deactivate(struct lwp *l)
+{
 	struct pmap * const pmap = l->l_proc->p_vmspace->vm_map.pmap;
 #ifdef DEBUG
 	if (pmapdebug & PDB_FOLLOW)
 		printf("pmap_deactivate(%p)\n", l);
 #endif
 	KASSERT(kpreempt_disabled());
 	struct cpu_info * const ci = curcpu();
 	KASSERT(l == ci->ci_curlwp);
 	KASSERT(pmap == ci->ci_pmap);
 	/*
 	 * There is no need to switch to a different PTBR here,
 	 * because a pmap_activate() or SWPCTX is guaranteed
 	 * before whatever lev1map we're on now is invalidated
 	 * or before user space is accessed again.
+	 *
 	 * Because only kernel mappings will be accessed before the
 	 * next pmap_activate() call, we consider our CPU to be on
 	 * the kernel pmap.
 	 */
 	ci->ci_pmap = pmap_kernel();
 	KASSERT(atomic_load_relaxed(&pmap->pm_count) > 1);
 	pmap_destroy(pmap);
+}
 /*
  * pmap_zero_page:		[ INTERFACE ]
+ *
  *	Zero the specified (machine independent) page by mapping the page
  *	into virtual memory and clear its contents, one machine dependent
  *	page at a time.
+ *
  *	Note: no locking is necessary in this function.
  */
 void
 pmap_zero_page(paddr_t phys)
+{
 	u_long *p0, *p1, *pend;
 #ifdef DEBUG
 	if (pmapdebug & PDB_FOLLOW)
 		printf("pmap_zero_page(%lx)\n", phys);
 #endif
 	p0 = (u_long *)ALPHA_PHYS_TO_K0SEG(phys);
 	p1 = NULL;
 	pend = (u_long *)((u_long)p0 + PAGE_SIZE);
 	/*
 	 * Unroll the loop a bit, doing 16 quadwords per iteration.
 	 * Do only 8 back-to-back stores, and alternate registers.
 	 */
 	do {
 		__asm volatile(
 		"# BEGIN loop body\n"
 		"	addq	%2, (8 * 8), %1		\n"
 		"	stq	$31, (0 * 8)(%0)	\n"
 		"	stq	$31, (1 * 8)(%0)	\n"
 		"	stq	$31, (2 * 8)(%0)	\n"
 		"	stq	$31, (3 * 8)(%0)	\n"
 		"	stq	$31, (4 * 8)(%0)	\n"
 		"	stq	$31, (5 * 8)(%0)	\n"
 		"	stq	$31, (6 * 8)(%0)	\n"
 		"	stq	$31, (7 * 8)(%0)	\n"
 		"					\n"
 		"	addq	%3, (8 * 8), %0		\n"
 		"	stq	$31, (0 * 8)(%1)	\n"
 		"	stq	$31, (1 * 8)(%1)	\n"
 		"	stq	$31, (2 * 8)(%1)	\n"
 		"	stq	$31, (3 * 8)(%1)	\n"
 		"	stq	$31, (4 * 8)(%1)	\n"
 		"	stq	$31, (5 * 8)(%1)	\n"
 		"	stq	$31, (6 * 8)(%1)	\n"
 		"	stq	$31, (7 * 8)(%1)	\n"
 		"	# END loop body"
 		: "=r" (p0), "=r" (p1)
 		: "0" (p0), "1" (p1)
 		: "memory");
 	} while (p0 < pend);
+}
 /*
  * pmap_copy_page:		[ INTERFACE ]
+ *
  *	Copy the specified (machine independent) page by mapping the page
  *	into virtual memory and using memcpy to copy the page, one machine
  *	dependent page at a time.
+ *
  *	Note: no locking is necessary in this function.
  */
 void
 pmap_copy_page(paddr_t src, paddr_t dst)
+{
 	const void *s;
 	void *d;
 #ifdef DEBUG
 	if (pmapdebug & PDB_FOLLOW)
 		printf("pmap_copy_page(%lx, %lx)\n", src, dst);
 #endif
 	s = (const void *)ALPHA_PHYS_TO_K0SEG(src);
 	d = (void *)ALPHA_PHYS_TO_K0SEG(dst);
 	memcpy(d, s, PAGE_SIZE);
+}
 /*
  * pmap_pageidlezero:		[ INTERFACE ]
+ *
  *	Page zero'er for the idle loop.  Returns true if the
  *	page was zero'd, FALSE if we aborted for some reason.
  */
 bool
 pmap_pageidlezero(paddr_t pa)
+{
 	u_long *ptr;
 	int i, cnt = PAGE_SIZE / sizeof(u_long);
 	for (i = 0, ptr = (u_long *) ALPHA_PHYS_TO_K0SEG(pa); i < cnt; i++) {
 		if (sched_curcpu_runnable_p()) {
 			/*
 			 * An LWP has become ready.  Abort now,
 			 * so we don't keep it waiting while we
 			 * finish zeroing the page.
 			 */
 			return (false);
+		}
 		*ptr++ = 0;
+	}
 	return (true);
+}
 /*
  * pmap_clear_modify:		[ INTERFACE ]
+ *
  *	Clear the modify bits on the specified physical page.
  */
 bool
 pmap_clear_modify(struct vm_page *pg)
+{
 	struct vm_page_md * const md = VM_PAGE_TO_MD(pg);
 	bool rv = false;
 	kmutex_t *lock;
 	struct pmap_tlb_context tlbctx;
 #ifdef DEBUG
 	if (pmapdebug & PDB_FOLLOW)
 		printf("pmap_clear_modify(%p)\n", pg);
 #endif
 	pmap_tlb_context_init(&tlbctx, TLB_CTX_F_PV);
 	PMAP_HEAD_TO_MAP_LOCK();
 	lock = pmap_pvh_lock(pg);
 	mutex_enter(lock);
 	if (md->pvh_listx & PGA_MODIFIED) {
 		rv = true;
 		pmap_changebit(pg, PG_FOW, ~0UL, &tlbctx);
 		md->pvh_listx &= ~PGA_MODIFIED;
+	}
 	mutex_exit(lock);
 	PMAP_HEAD_TO_MAP_UNLOCK();
 	pmap_tlb_shootnow(&tlbctx);
 	TLB_COUNT(reason_clear_modify);
 	return (rv);
+}
 /*
  * pmap_clear_reference:	[ INTERFACE ]
+ *
  *	Clear the reference bit on the specified physical page.
  */
 bool
 pmap_clear_reference(struct vm_page *pg)
+{
 	struct vm_page_md * const md = VM_PAGE_TO_MD(pg);
 	bool rv = false;
 	kmutex_t *lock;
 	struct pmap_tlb_context tlbctx;
 #ifdef DEBUG
 	if (pmapdebug & PDB_FOLLOW)
 		printf("pmap_clear_reference(%p)\n", pg);
 #endif
 	pmap_tlb_context_init(&tlbctx, TLB_CTX_F_PV);
 	PMAP_HEAD_TO_MAP_LOCK();
 	lock = pmap_pvh_lock(pg);
 	mutex_enter(lock);
 	if (md->pvh_listx & PGA_REFERENCED) {
 		rv = true;
 		pmap_changebit(pg, PG_FOR | PG_FOW | PG_FOE, ~0UL, &tlbctx);
 		md->pvh_listx &= ~PGA_REFERENCED;
+	}
 	mutex_exit(lock);
 	PMAP_HEAD_TO_MAP_UNLOCK();
 	pmap_tlb_shootnow(&tlbctx);
 	TLB_COUNT(reason_clear_reference);
 	return (rv);
+}
 /*
  * pmap_is_referenced:		[ INTERFACE ]
+ *
  *	Return whether or not the specified physical page is referenced
  *	by any physical maps.
  */
 /* See <machine/pmap.h> */
 /*
  * pmap_is_modified:		[ INTERFACE ]
+ *
  *	Return whether or not the specified physical page is modified
  *	by any physical maps.
  */
 /* See <machine/pmap.h> */
 /*
  * pmap_phys_address:		[ INTERFACE ]
+ *
  *	Return the physical address corresponding to the specified
  *	cookie.  Used by the device pager to decode a device driver's
  *	mmap entry point return value.
+ *
  *	Note: no locking is necessary in this function.
  */
 paddr_t
 pmap_phys_address(paddr_t ppn)
+{
 	return (alpha_ptob(ppn));
+}
 /*
  * Miscellaneous support routines follow
  */
 /*
  * alpha_protection_init:
+ *
  *	Initialize Alpha protection code array.
+ *
  *	Note: no locking is necessary in this function.
  */
 static void
 alpha_protection_init(void)
+{
 	int prot, *kp, *up;
 	kp = protection_codes[0];
 	up = protection_codes[1];
 	for (prot = 0; prot < 8; prot++) {
 		kp[prot] = PG_ASM;
 		up[prot] = 0;
 		if (prot & VM_PROT_READ) {
 			kp[prot] |= PG_KRE;
 			up[prot] |= PG_KRE | PG_URE;
+		}
 		if (prot & VM_PROT_WRITE) {
 			kp[prot] |= PG_KWE;
 			up[prot] |= PG_KWE | PG_UWE;
+		}
 		if (prot & VM_PROT_EXECUTE) {
 			kp[prot] |= PG_EXEC | PG_KRE;
 			up[prot] |= PG_EXEC | PG_KRE | PG_URE;
 		} else {
 			kp[prot] |= PG_FOE;
 			up[prot] |= PG_FOE;
+		}
+	}
+}
 /*
  * pmap_remove_mapping:
+ *
  *	Invalidate a single page denoted by pmap/va.
+ *
  *	If (pte != NULL), it is the already computed PTE for the page.
+ *
  *	Note: locking in this function is complicated by the fact
  *	that we can be called when the PV list is already locked.
  *	(pmap_page_protect()).  In this case, the caller must be
  *	careful to get the next PV entry while we remove this entry
  *	from beneath it.  We assume that the pmap itself is already
  *	locked; dolock applies only to the PV list.
+ *
  *	Returns important PTE bits that the caller needs to check for
  *	TLB / I-stream invalidation purposes.
  */
 static pt_entry_t
 pmap_remove_mapping(pmap_t pmap, vaddr_t va, pt_entry_t *pte,
     bool dolock, pv_entry_t *opvp, struct pmap_tlb_context * const tlbctx)
+{
 	pt_entry_t opte;
 	paddr_t pa;
 	struct vm_page *pg;		/* if != NULL, page is managed */
 #ifdef DEBUG
 	if (pmapdebug & (PDB_FOLLOW|PDB_REMOVE|PDB_PROTECT))
 		printf("pmap_remove_mapping(%p, %lx, %p, %d, %p)\n",
 		       pmap, va, pte, dolock, opvp);
 #endif
 	/*
 	 * PTE not provided, compute it from pmap and va.
 	 */
 	if (pte == NULL) {
 		pte = pmap_l3pte(pmap_lev1map(pmap), va, NULL);
 		if (pmap_pte_v(pte) == 0)
 			return 0;
+	}
 	opte = *pte;
 	pa = PG_PFNUM(opte) << PGSHIFT;
 	/*
 	 * Update statistics
 	 */
 	if (pmap_pte_w(pte))
 		PMAP_STAT_DECR(pmap->pm_stats.wired_count, 1);
 	PMAP_STAT_DECR(pmap->pm_stats.resident_count, 1);
 	/*
 	 * Invalidate the PTE after saving the reference modify info.
 	 */
 #ifdef DEBUG
 	if (pmapdebug & PDB_REMOVE)
 		printf("remove: invalidating pte at %p\n", pte);
 #endif
 	atomic_store_relaxed(pte, PG_NV);
 	/*
 	 * If we're removing a user mapping, check to see if we
 	 * can free page table pages.
 	 */
 	if (pmap != pmap_kernel()) {
 		/*
 		 * Delete the reference on the level 3 table.  It will
 		 * delete references on the level 2 and 1 tables as
 		 * appropriate.
 		 */
 		pmap_l3pt_delref(pmap, va, pte, tlbctx);
+	}
 	if (opte & PG_PVLIST) {
 		/*
 		 * Remove it from the PV table.
 		 */
 		pg = PHYS_TO_VM_PAGE(pa);
 		KASSERT(pg != NULL);
 		pmap_pv_remove(pmap, pg, va, dolock, opvp);
 		KASSERT(opvp == NULL || *opvp != NULL);
+	}
 	return opte & (PG_V | PG_ASM | PG_EXEC);
+}
 /*
  * pmap_changebit:
+ *
  *	Set or clear the specified PTE bits for all mappings on the
  *	specified page.
+ *
  *	Note: we assume that the pv_head is already locked, and that
  *	the caller has acquired a PV->pmap mutex so that we can lock
  *	the pmaps as we encounter them.
  */
 static void
 pmap_changebit(struct vm_page *pg, pt_entry_t set, pt_entry_t mask,
     struct pmap_tlb_context * const tlbctx)
+{
 	pv_entry_t pv;
 	pt_entry_t *pte, npte, opte;
 #ifdef DEBUG
 	if (pmapdebug & PDB_BITS)
 		printf("pmap_changebit(%p, 0x%lx, 0x%lx)\n",
 		    pg, set, mask);
 #endif
 	/*
 	 * Loop over all current mappings setting/clearing as apropos.
 	 */
 	for (pv = VM_MDPAGE_PVS(pg); pv != NULL; pv = pv->pv_next) {
 		PMAP_LOCK(pv->pv_pmap);
 		pte = pv->pv_pte;
 		opte = atomic_load_relaxed(pte);
 		npte = (opte | set) & mask;
 		if (npte != opte) {
 			atomic_store_relaxed(pte, npte);
 			pmap_tlb_shootdown_pv(pv->pv_pmap, pv->pv_va,
 			    opte, tlbctx);
+		}
 		PMAP_UNLOCK(pv->pv_pmap);
+	}
+}
 /*
  * pmap_emulate_reference:
+ *
  *	Emulate reference and/or modified bit hits.
  *	Return 1 if this was an execute fault on a non-exec mapping,
  *	otherwise return 0.
  */
 int
 pmap_emulate_reference(struct lwp *l, vaddr_t v, int user, int type)
+{
 	struct pmap *pmap = l->l_proc->p_vmspace->vm_map.pmap;
 	pt_entry_t faultoff, *pte;
 	struct vm_page *pg;
 	paddr_t pa;
 	bool didlock = false;
 	bool exec = false;
 	kmutex_t *lock;
 #ifdef DEBUG
 	if (pmapdebug & PDB_FOLLOW)
 		printf("pmap_emulate_reference: %p, 0x%lx, %d, %d\n",
 		    l, v, user, type);
 #endif
 	/*
 	 * Convert process and virtual address to physical address.
 	 */
 	if (v >= VM_MIN_KERNEL_ADDRESS) {
 		if (user)
 			panic("pmap_emulate_reference: user ref to kernel");
 		/*
 		 * No need to lock here; kernel PT pages never go away.
 		 */
 		pte = PMAP_KERNEL_PTE(v);
 	} else {
 #ifdef DIAGNOSTIC
 		if (l == NULL)
 			panic("pmap_emulate_reference: bad proc");
 		if (l->l_proc->p_vmspace == NULL)
 			panic("pmap_emulate_reference: bad p_vmspace");
 #endif
 		PMAP_LOCK(pmap);
 		didlock = true;
 		pte = pmap_l3pte(pmap_lev1map(pmap), v, NULL);
 		/*
 		 * We'll unlock below where we're done with the PTE.
 		 */
+	}
 	exec = pmap_pte_exec(pte);
 	if (!exec && type == ALPHA_MMCSR_FOE) {
 		if (didlock)
 			PMAP_UNLOCK(pmap);
 	       return (1);
+	}
 #ifdef DEBUG
 	if (pmapdebug & PDB_FOLLOW) {
 		printf("\tpte = %p, ", pte);
 		printf("*pte = 0x%lx\n", *pte);
+	}
 #endif
 	pa = pmap_pte_pa(pte);
 	/*
 	 * We're now done with the PTE.  If it was a user pmap, unlock
 	 * it now.
 	 */
 	if (didlock)
 		PMAP_UNLOCK(pmap);
 #ifdef DEBUG
 	if (pmapdebug & PDB_FOLLOW)
 		printf("\tpa = 0x%lx\n", pa);
 #endif
 #ifdef DIAGNOSTIC
 	if (!uvm_pageismanaged(pa))
 		panic("pmap_emulate_reference(%p, 0x%lx, %d, %d): "
 		      "pa 0x%lx not managed", l, v, user, type, pa);
 #endif
 	/*
 	 * Twiddle the appropriate bits to reflect the reference
 	 * and/or modification..
+	 *
 	 * The rules:
 	 * 	(1) always mark page as used, and
 	 *	(2) if it was a write fault, mark page as modified.
 	 */
 	pg = PHYS_TO_VM_PAGE(pa);
 	struct vm_page_md * const md = VM_PAGE_TO_MD(pg);
 	struct pmap_tlb_context tlbctx;
 	pmap_tlb_context_init(&tlbctx, TLB_CTX_F_PV);
 	PMAP_HEAD_TO_MAP_LOCK();
 	lock = pmap_pvh_lock(pg);
 	mutex_enter(lock);
 	if (type == ALPHA_MMCSR_FOW) {
 		md->pvh_listx |= (PGA_REFERENCED|PGA_MODIFIED);
 		faultoff = PG_FOR | PG_FOW;
 	} else {
 		md->pvh_listx |= PGA_REFERENCED;
 		faultoff = PG_FOR;
 		if (exec) {
 			faultoff |= PG_FOE;
+		}
+	}
 	pmap_changebit(pg, 0, ~faultoff, &tlbctx);
 	mutex_exit(lock);
 	PMAP_HEAD_TO_MAP_UNLOCK();
 	pmap_tlb_shootnow(&tlbctx);
 	TLB_COUNT(reason_emulate_reference);
 	return (0);
+}
 #ifdef DEBUG
 /*
  * pmap_pv_dump:
+ *
  *	Dump the physical->virtual data for the specified page.
  */
 void
 pmap_pv_dump(paddr_t pa)
+{
 	struct vm_page *pg;
 	struct vm_page_md *md;
 	pv_entry_t pv;
 	kmutex_t *lock;
 	pg = PHYS_TO_VM_PAGE(pa);
 	md = VM_PAGE_TO_MD(pg);
 	lock = pmap_pvh_lock(pg);
 	mutex_enter(lock);
 	printf("pa 0x%lx (attrs = 0x%x):\n", pa, md->pvh_listx & PGA_ATTRS);
 	for (pv = VM_MDPAGE_PVS(pg); pv != NULL; pv = pv->pv_next)
 		printf("     pmap %p, va 0x%lx\n",
 		    pv->pv_pmap, pv->pv_va);
 	printf("\n");
 	mutex_exit(lock);
+}
 #endif
 /*
  * vtophys:
+ *
  *	Return the physical address corresponding to the K0SEG or
  *	K1SEG address provided.
+ *
  *	Note: no locking is necessary in this function.
  */
 static bool
 vtophys_internal(vaddr_t const vaddr, paddr_t * const pap)
+{
 	paddr_t pa;
 	KASSERT(vaddr >= ALPHA_K0SEG_BASE);
 	if (vaddr <= ALPHA_K0SEG_END) {
 		pa = ALPHA_K0SEG_TO_PHYS(vaddr);
 	} else {
 		pt_entry_t * const pte = PMAP_KERNEL_PTE(vaddr);
 		if (__predict_false(! pmap_pte_v(pte))) {
 			return false;
+		}
 		pa = pmap_pte_pa(pte) | (vaddr & PGOFSET);
+	}
 	if (pap != NULL) {
 		*pap = pa;
+	}
 	return true;
+}
 paddr_t
 vtophys(vaddr_t const vaddr)
+{
 	paddr_t pa;
 	if (__predict_false(! vtophys_internal(vaddr, &pa)))
 		pa = 0;
 	return pa;
+}
 /******************** pv_entry management ********************/
 /*
  * pmap_pv_enter:
+ *
  *	Add a physical->virtual entry to the pv_table.
  */
 static int
 pmap_pv_enter(pmap_t pmap, struct vm_page *pg, vaddr_t va, pt_entry_t *pte,
     bool dolock, pv_entry_t newpv)
+{
 	struct vm_page_md * const md = VM_PAGE_TO_MD(pg);
 	kmutex_t *lock;
 	/*
 	 * Allocate and fill in the new pv_entry.
 	 */
 	if (newpv == NULL) {
 		newpv = pmap_pv_alloc();
 		if (newpv == NULL)
 			return ENOMEM;
+	}
 	newpv->pv_va = va;
 	newpv->pv_pmap = pmap;
 	newpv->pv_pte = pte;
 	if (dolock) {
 		lock = pmap_pvh_lock(pg);
 		mutex_enter(lock);
+	}
 #ifdef DEBUG
+    {
 	pv_entry_t pv;
 	/*
 	 * Make sure the entry doesn't already exist.
 	 */
 	for (pv = VM_MDPAGE_PVS(pg); pv != NULL; pv = pv->pv_next) {
 		if (pmap == pv->pv_pmap && va == pv->pv_va) {
 			printf("pmap = %p, va = 0x%lx\n", pmap, va);
 			panic("pmap_pv_enter: already in pv table");
+		}
+	}
+    }
 #endif
 	/*
 	 * ...and put it in the list.
 	 */
 	uintptr_t const attrs = md->pvh_listx & PGA_ATTRS;
 	newpv->pv_next = (struct pv_entry *)(md->pvh_listx & ~PGA_ATTRS);
 	md->pvh_listx = (uintptr_t)newpv | attrs;
 	LIST_INSERT_HEAD(&pmap->pm_pvents, newpv, pv_link);
 	if (dolock) {
 		mutex_exit(lock);
+	}
 	return 0;
+}
 /*
  * pmap_pv_remove:
+ *
  *	Remove a physical->virtual entry from the pv_table.
  */
 static void
 pmap_pv_remove(pmap_t pmap, struct vm_page *pg, vaddr_t va, bool dolock,
 	pv_entry_t *opvp)
+{
 	struct vm_page_md * const md = VM_PAGE_TO_MD(pg);
 	pv_entry_t pv, *pvp;
 	kmutex_t *lock;
 	if (dolock) {
 		lock = pmap_pvh_lock(pg);
 		mutex_enter(lock);
 	} else {
 		lock = NULL; /* XXX stupid gcc */
+	}
 	/*
 	 * Find the entry to remove.
 	 */
 	for (pvp = (struct pv_entry **)&md->pvh_listx, pv = VM_MDPAGE_PVS(pg);
 	     pv != NULL; pvp = &pv->pv_next, pv = *pvp)
 		if (pmap == pv->pv_pmap && va == pv->pv_va)
 			break;
 	KASSERT(pv != NULL);
 	/*
 	 * The page attributes are in the lower 2 bits of the first
 	 * PV entry pointer.  Rather than comparing the pointer address
 	 * and branching, we just always preserve what might be there
 	 * (either attribute bits or zero bits).
 	 */
 	*pvp = (pv_entry_t)((uintptr_t)pv->pv_next |
 			    (((uintptr_t)*pvp) & PGA_ATTRS));
 	LIST_REMOVE(pv, pv_link);
 	if (dolock) {
 		mutex_exit(lock);
+	}
 	if (opvp != NULL)
 		*opvp = pv;
 	else
 		pmap_pv_free(pv);
+}
 /*
  * pmap_pv_page_alloc:
+ *
  *	Allocate a page for the pv_entry pool.
  */
 static void *
 pmap_pv_page_alloc(struct pool *pp, int flags)
+{
 	struct vm_page * const pg = pmap_physpage_alloc(PGU_PVENT);
 	if (__predict_false(pg == NULL)) {
 		return NULL;
+	}
 	return (void *)ALPHA_PHYS_TO_K0SEG(VM_PAGE_TO_PHYS(pg));
+}
 /*
  * pmap_pv_page_free:
+ *
  *	Free a pv_entry pool page.
  */
 static void
 pmap_pv_page_free(struct pool *pp, void *v)
+{
 	pmap_physpage_free(ALPHA_K0SEG_TO_PHYS((vaddr_t)v));
+}
 /******************** misc. functions ********************/
 /*
  * Pages that are in-use as page table pages should never be part
  * of a UVM loan, so we'll use that field for our PT page reference
  * count.
  */
 #define	PHYSPAGE_REFCNT(pg)	atomic_load_relaxed(&(pg)->loan_count)
 #define	PHYSPAGE_REFCNT_INC(pg)	atomic_inc_uint_nv(&(pg)->loan_count)
 #define	PHYSPAGE_REFCNT_DEC(pg)	atomic_dec_uint_nv(&(pg)->loan_count)
 /*
  * pmap_physpage_alloc:
+ *
  *	Allocate a single page from the VM system and return the
  *	physical address for that page.
  */
 static struct vm_page *
 pmap_physpage_alloc(int usage)
+{
 	struct vm_page *pg;
 	/*
 	 * Don't ask for a zero'd page in the L1PT case -- we will
 	 * properly initialize it in the constructor.
 	 */
 	pg = uvm_pagealloc(NULL, 0, NULL, usage == PGU_L1PT ?
 	    UVM_PGA_USERESERVE : UVM_PGA_USERESERVE|UVM_PGA_ZERO);
 	if (pg != NULL) {
 		KASSERT(PHYSPAGE_REFCNT(pg) == 0);
+	}
 	return pg;
+}
 /*
  * pmap_physpage_free:
+ *
  *	Free the single page table page at the specified physical address.
  */
 static void
 pmap_physpage_free(paddr_t pa)
+{
 	struct vm_page *pg;
 	if ((pg = PHYS_TO_VM_PAGE(pa)) == NULL)
 		panic("pmap_physpage_free: bogus physical page address");
 	KASSERT(PHYSPAGE_REFCNT(pg) == 0);
 	uvm_pagefree(pg);
+}
 /*
  * pmap_physpage_addref:
+ *
  *	Add a reference to the specified special use page.
  */
 static int
 pmap_physpage_addref(void *kva)
+{
 	struct vm_page *pg;
 	paddr_t pa;
 	pa = ALPHA_K0SEG_TO_PHYS(trunc_page((vaddr_t)kva));
 	pg = PHYS_TO_VM_PAGE(pa);
 	KASSERT(PHYSPAGE_REFCNT(pg) < UINT32_MAX);
 	return PHYSPAGE_REFCNT_INC(pg);
+}
 /*
  * pmap_physpage_delref:
+ *
  *	Delete a reference to the specified special use page.
  */
 static int
 pmap_physpage_delref(void *kva)
+{
 	struct vm_page *pg;
 	paddr_t pa;
 	pa = ALPHA_K0SEG_TO_PHYS(trunc_page((vaddr_t)kva));
 	pg = PHYS_TO_VM_PAGE(pa);
 	KASSERT(PHYSPAGE_REFCNT(pg) != 0);
 	return PHYSPAGE_REFCNT_DEC(pg);
+}
 /******************** page table page management ********************/
 static bool
 pmap_kptpage_alloc(paddr_t *pap)
+{
 	if (uvm.page_init_done == false) {
 		/*
 		 * We're growing the kernel pmap early (from
 		 * uvm_pageboot_alloc()).  This case must
 		 * be handled a little differently.
 		 */
 		*pap = ALPHA_K0SEG_TO_PHYS(
 		    pmap_steal_memory(PAGE_SIZE, NULL, NULL));
 		return true;
+	}
 	struct vm_page * const pg = pmap_physpage_alloc(PGU_NORMAL);
 	if (__predict_true(pg != NULL)) {
 		*pap = VM_PAGE_TO_PHYS(pg);
 		return true;
+	}
 	return false;
+}
 /*
  * pmap_growkernel:		[ INTERFACE ]
+ *
  *	Grow the kernel address space.  This is a hint from the
  *	upper layer to pre-allocate more kernel PT pages.
  */
 vaddr_t
 pmap_growkernel(vaddr_t maxkvaddr)
+{
 	struct pmap *pm;
 	paddr_t ptaddr;
 	pt_entry_t *l1pte, *l2pte, pte;
 	pt_entry_t *lev1map;
 	vaddr_t va;
 	int l1idx;
 	rw_enter(&pmap_growkernel_lock, RW_WRITER);
 	if (maxkvaddr <= virtual_end)
 		goto out;		/* we are OK */
 	va = virtual_end;
 	while (va < maxkvaddr) {
 		/*
 		 * If there is no valid L1 PTE (i.e. no L2 PT page),
 		 * allocate a new L2 PT page and insert it into the
 		 * L1 map.
 		 */
 		l1pte = pmap_l1pte(kernel_lev1map, va);
 		if (pmap_pte_v(l1pte) == 0) {
 			if (!pmap_kptpage_alloc(&ptaddr))
 				goto die;
 			pte = (atop(ptaddr) << PG_SHIFT) |
 			    PG_V | PG_ASM | PG_KRE | PG_KWE | PG_WIRED;
 			*l1pte = pte;
 			l1idx = l1pte_index(va);
 			/* Update all the user pmaps. */
 			mutex_enter(&pmap_all_pmaps_lock);
 			for (pm = TAILQ_FIRST(&pmap_all_pmaps);
 			     pm != NULL; pm = TAILQ_NEXT(pm, pm_list)) {
 				/* Skip the kernel pmap. */
 				if (pm == pmap_kernel())
 					continue;
 				/*
 				 * Any pmaps published on the global list
 				 * should never be referencing kernel_lev1map.
 				 */
 				lev1map = pmap_lev1map(pm);
 				KASSERT(lev1map != kernel_lev1map);
 				PMAP_LOCK(pm);
 				lev1map[l1idx] = pte;
 				PMAP_UNLOCK(pm);
+			}
 			mutex_exit(&pmap_all_pmaps_lock);
+		}
 		/*
 		 * Have an L2 PT page now, add the L3 PT page.
 		 */
 		l2pte = pmap_l2pte(kernel_lev1map, va, l1pte);
 		KASSERT(pmap_pte_v(l2pte) == 0);
 		if (!pmap_kptpage_alloc(&ptaddr))
 			goto die;
 		*l2pte = (atop(ptaddr) << PG_SHIFT) |
 		    PG_V | PG_ASM | PG_KRE | PG_KWE | PG_WIRED;
 		va += ALPHA_L2SEG_SIZE;
+	}
 	/* Invalidate the L1 PT cache. */
 	pool_cache_invalidate(&pmap_l1pt_cache);
 	virtual_end = va;
  out:
 	rw_exit(&pmap_growkernel_lock);
 	return (virtual_end);
  die:
 	panic("pmap_growkernel: out of memory");
+}
 /*
  * pmap_l1pt_ctor:
+ *
  *	Pool cache constructor for L1 PT pages.
+ *
  *	Note: The growkernel lock is held across allocations
  *	from our pool_cache, so we don't need to acquire it
  *	ourselves.
  */
 static int
 pmap_l1pt_ctor(void *arg, void *object, int flags)
+{
 	pt_entry_t *l1pt = object, pte;
 	int i;
 	/*
 	 * Initialize the new level 1 table by zeroing the
 	 * user portion and copying the kernel mappings into
 	 * the kernel portion.
 	 */
 	for (i = 0; i < l1pte_index(VM_MIN_KERNEL_ADDRESS); i++)
 		l1pt[i] = 0;
 	for (i = l1pte_index(VM_MIN_KERNEL_ADDRESS);
 	     i <= l1pte_index(VM_MAX_KERNEL_ADDRESS); i++)
 		l1pt[i] = kernel_lev1map[i];
 	/*
 	 * Now, map the new virtual page table.  NOTE: NO ASM!
 	 */
 	pte = ((ALPHA_K0SEG_TO_PHYS((vaddr_t) l1pt) >> PGSHIFT) << PG_SHIFT) |
 	    PG_V | PG_KRE | PG_KWE;
 	l1pt[l1pte_index(VPTBASE)] = pte;
 	return (0);
+}
 /*
  * pmap_l1pt_alloc:
+ *
  *	Page alloctaor for L1 PT pages.
  */
 static void *
 pmap_l1pt_alloc(struct pool *pp, int flags)
+{
 	/*
 	 * Attempt to allocate a free page.
 	 */
 	struct vm_page * const pg = pmap_physpage_alloc(PGU_L1PT);
 	if (__predict_false(pg == NULL)) {
 		return NULL;
+	}
 	return (void *)ALPHA_PHYS_TO_K0SEG(VM_PAGE_TO_PHYS(pg));
+}
 /*
  * pmap_l1pt_free:
+ *
  *	Page freer for L1 PT pages.
  */
 static void
 pmap_l1pt_free(struct pool *pp, void *v)
+{
 	pmap_physpage_free(ALPHA_K0SEG_TO_PHYS((vaddr_t) v));
+}
 /*
  * pmap_ptpage_alloc:
+ *
  *	Allocate a level 2 or level 3 page table page for a user
  *	pmap, and initialize the PTE that references it.
+ *
  *	Note: the pmap must already be locked.
  */
 static int
 pmap_ptpage_alloc(pmap_t pmap, pt_entry_t * const pte, int const usage)
+{
 	/*
 	 * Allocate the page table page.
 	 */
 	struct vm_page * const pg = pmap_physpage_alloc(usage);
 	if (__predict_false(pg == NULL)) {
 		return ENOMEM;
+	}
 	LIST_INSERT_HEAD(&pmap->pm_ptpages, pg, pageq.list);
 	/*
 	 * Initialize the referencing PTE.
 	 */
 	const pt_entry_t npte = ((VM_PAGE_TO_PHYS(pg) >> PGSHIFT) << PG_SHIFT) |
 	    PG_V | PG_KRE | PG_KWE | PG_WIRED;
 	atomic_store_relaxed(pte, npte);
 	return (0);
+}
 /*
  * pmap_ptpage_free:
+ *
  *	Free the level 2 or level 3 page table page referenced
  *	be the provided PTE.
+ *
  *	Note: the pmap must already be locked.
  */
 static void
 pmap_ptpage_free(pmap_t pmap, pt_entry_t * const pte,
     struct pmap_tlb_context * const tlbctx)
+{
 	/*
 	 * Extract the physical address of the page from the PTE
 	 * and clear the entry.
 	 */
 	const paddr_t ptpa = pmap_pte_pa(pte);
 	atomic_store_relaxed(pte, PG_NV);
 	struct vm_page * const pg = PHYS_TO_VM_PAGE(ptpa);
 	KASSERT(pg != NULL);
 	KASSERT(PHYSPAGE_REFCNT(pg) == 0);
 #ifdef DEBUG
 	pmap_zero_page(ptpa);
 #endif
 	LIST_REMOVE(pg, pageq.list);
 	LIST_INSERT_HEAD(&tlbctx->t_freeptq, pg, pageq.list);
+}
 /*
  * pmap_l3pt_delref:
+ *
  *	Delete a reference on a level 3 PT page.  If the reference drops
  *	to zero, free it.
+ *
  *	Note: the pmap must already be locked.
  */
 static void
 pmap_l3pt_delref(pmap_t pmap, vaddr_t va, pt_entry_t *l3pte,
     struct pmap_tlb_context * const tlbctx)
+{
 	pt_entry_t *l1pte, *l2pte;
 	pt_entry_t * const lev1map = pmap_lev1map(pmap);
 	l1pte = pmap_l1pte(lev1map, va);
 	l2pte = pmap_l2pte(lev1map, va, l1pte);
 #ifdef DIAGNOSTIC
 	if (pmap == pmap_kernel())
 		panic("pmap_l3pt_delref: kernel pmap");
 #endif
 	if (pmap_physpage_delref(l3pte) == 0) {
 		/*
 		 * No more mappings; we can free the level 3 table.
 		 */
 #ifdef DEBUG
 		if (pmapdebug & PDB_PTPAGE)
 			printf("pmap_l3pt_delref: freeing level 3 table at "
 			    "0x%lx\n", pmap_pte_pa(l2pte));
 #endif
 		/*
 		 * You can pass NULL if you know the last refrence won't
 		 * be dropped.
 		 */
 		KASSERT(tlbctx != NULL);
 		pmap_ptpage_free(pmap, l2pte, tlbctx);
 		/*
 		 * We've freed a level 3 table, so we must invalidate
 		 * any now-stale TLB entries for the corresponding VPT
 		 * VA range.  Easiest way to guarantee this is to hit
 		 * all of the user TLB entries.
 		 */
 		pmap_tlb_shootdown_all_user(pmap, PG_V, tlbctx);
 		/*
 		 * We've freed a level 3 table, so delete the reference
 		 * on the level 2 table.
 		 */
 		pmap_l2pt_delref(pmap, l1pte, l2pte, tlbctx);
+	}
+}
 /*
  * pmap_l2pt_delref:
+ *
  *	Delete a reference on a level 2 PT page.  If the reference drops
  *	to zero, free it.
+ *
  *	Note: the pmap must already be locked.
  */
 static void
 pmap_l2pt_delref(pmap_t pmap, pt_entry_t *l1pte, pt_entry_t *l2pte,
     struct pmap_tlb_context * const tlbctx)
+{
 #ifdef DIAGNOSTIC
 	if (pmap == pmap_kernel())
 		panic("pmap_l2pt_delref: kernel pmap");
 #endif
 	if (pmap_physpage_delref(l2pte) == 0) {
 		/*
 		 * No more mappings in this segment; we can free the
 		 * level 2 table.
 		 */
 #ifdef DEBUG
 		if (pmapdebug & PDB_PTPAGE)
 			printf("pmap_l2pt_delref: freeing level 2 table at "
 			    "0x%lx\n", pmap_pte_pa(l1pte));
 #endif
 		/*
 		 * You can pass NULL if you know the last refrence won't
 		 * be dropped.
 		 */
 		KASSERT(tlbctx != NULL);
 		pmap_ptpage_free(pmap, l1pte, tlbctx);
 		/*
 		 * We've freed a level 2 table, so we must invalidate
 		 * any now-stale TLB entries for the corresponding VPT
 		 * VA range.  Easiest way to guarantee this is to hit
 		 * all of the user TLB entries.
 		 */
 		pmap_tlb_shootdown_all_user(pmap, PG_V, tlbctx);
 		/*
 		 * We've freed a level 2 table, so delete the reference
 		 * on the level 1 table.
 		 */
 		pmap_l1pt_delref(pmap, l1pte);
+	}
+}
 /*
  * pmap_l1pt_delref:
+ *
  *	Delete a reference on a level 1 PT page.
  */
 static void
 pmap_l1pt_delref(pmap_t pmap, pt_entry_t *l1pte)
+{
 	KASSERT(pmap != pmap_kernel());
 	(void)pmap_physpage_delref(l1pte);
+}
 /******************** Address Space Number management ********************/
 /*
  * pmap_asn_alloc:
+ *
  *	Allocate and assign an ASN to the specified pmap.
+ *
  *	Note: the pmap must already be locked.  This may be called from
  *	an interprocessor interrupt, and in that case, the sender of
  *	the IPI has the pmap lock.
  */
 static u_int
 pmap_asn_alloc(pmap_t const pmap, struct cpu_info * const ci)
+{
 #ifdef DEBUG
 	if (pmapdebug & (PDB_FOLLOW|PDB_ASN))
 		printf("pmap_asn_alloc(%p)\n", pmap);
 #endif
 	KASSERT(pmap != pmap_kernel());
 	KASSERT(pmap->pm_percpu[ci->ci_cpuid].pmc_lev1map != kernel_lev1map);
 	KASSERT(kpreempt_disabled());
 	/* No work to do if the the CPU does not implement ASNs. */
 	if (pmap_max_asn == 0)
 		return 0;
 	struct pmap_percpu * const pmc = &pmap->pm_percpu[ci->ci_cpuid];
 	/*
 	 * Hopefully, we can continue using the one we have...
+	 *
 	 * N.B. the generation check will fail the first time
 	 * any pmap is activated on a given CPU, because we start
 	 * the generation counter at 1, but initialize pmaps with
 	 * 0; this forces the first ASN allocation to occur.
 	 */
 	if (pmc->pmc_asngen == ci->ci_asn_gen) {
 #ifdef DEBUG
 		if (pmapdebug & PDB_ASN)
 			printf("pmap_asn_alloc: same generation, keeping %u\n",
 			    pmc->pmc_asn);
 #endif
 		TLB_COUNT(asn_reuse);
 		return pmc->pmc_asn;
+	}
 	/*
 	 * Need to assign a new ASN.  Grab the next one, incrementing
 	 * the generation number if we have to.
 	 */
 	if (ci->ci_next_asn > pmap_max_asn) {
 		/*
 		 * Invalidate all non-PG_ASM TLB entries and the
 		 * I-cache, and bump the generation number.
 		 */
 		ALPHA_TBIAP();
 		alpha_pal_imb();
 		ci->ci_next_asn = PMAP_ASN_FIRST_USER;
 		ci->ci_asn_gen++;
 		TLB_COUNT(asn_newgen);
 		/*
 		 * Make sure the generation number doesn't wrap.  We could
 		 * handle this scenario by traversing all of the pmaps,
 		 * and invalidating the generation number on those which
 		 * are not currently in use by this processor.
+		 *
 		 * However... considering that we're using an unsigned 64-bit
 		 * integer for generation numbers, on non-ASN CPUs, we won't
 		 * wrap for approximately 75 billion years on a 128-ASN CPU
 		 * (assuming 1000 switch * operations per second).
+		 *
 		 * So, we don't bother.
 		 */
 		KASSERT(ci->ci_asn_gen != PMAP_ASNGEN_INVALID);
 #ifdef DEBUG
 		if (pmapdebug & PDB_ASN)
 			printf("pmap_asn_alloc: generation bumped to %lu\n",
 			    ci->ci_asn_ge);
 #endif
+	}
 	/*
 	 * Assign the new ASN and validate the generation number.
 	 */
 	pmc->pmc_asn = ci->ci_next_asn++;
 	pmc->pmc_asngen = ci->ci_asn_gen;
 	TLB_COUNT(asn_assign);
 	/*
 	 * We have a new ASN, so we can skip any pending I-stream sync
 	 * on the way back out to user space.
 	 */
 	pmc->pmc_needisync = 0;
 #ifdef DEBUG
 	if (pmapdebug & PDB_ASN)
 		printf("pmap_asn_alloc: assigning %u to pmap %p\n",
 		    pmc->pmc_asn, pmap);
 #endif
 	return pmc->pmc_asn;
+}