pmap.c revision 188507
1/*
2 * Copyright (c) 1991 Regents of the University of California.
3 * All rights reserved.
4 * Copyright (c) 1994 John S. Dyson
5 * All rights reserved.
6 * Copyright (c) 1994 David Greenman
7 * All rights reserved.
8 *
9 * This code is derived from software contributed to Berkeley by
10 * the Systems Programming Group of the University of Utah Computer
11 * Science Department and William Jolitz of UUNET Technologies Inc.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 *    notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 *    notice, this list of conditions and the following disclaimer in the
20 *    documentation and/or other materials provided with the distribution.
21 * 4. Neither the name of the University nor the names of its contributors
22 *    may be used to endorse or promote products derived from this software
23 *    without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 *
37 *	from:	@(#)pmap.c	7.7 (Berkeley)	5/12/91
38 *	from: src/sys/i386/i386/pmap.c,v 1.250.2.8 2000/11/21 00:09:14 ps
39 *	JNPR: pmap.c,v 1.11.2.1 2007/08/16 11:51:06 girish
40 */
41
42/*
43 *	Manages physical address maps.
44 *
45 *	In addition to hardware address maps, this
46 *	module is called upon to provide software-use-only
47 *	maps which may or may not be stored in the same
48 *	form as hardware maps.	These pseudo-maps are
49 *	used to store intermediate results from copy
50 *	operations to and from address spaces.
51 *
52 *	Since the information managed by this module is
53 *	also stored by the logical address mapping module,
54 *	this module may throw away valid virtual-to-physical
55 *	mappings at almost any time.  However, invalidations
56 *	of virtual-to-physical mappings must be done as
57 *	requested.
58 *
59 *	In order to cope with hardware architectures which
60 *	make virtual-to-physical map invalidates expensive,
61 *	this module may delay invalidate or reduced protection
62 *	operations until such time as they are actually
63 *	necessary.  This module is given full information as
64 *	to which processors are currently using which maps,
65 *	and to when physical maps must be made correct.
66 */
67
68#include <sys/cdefs.h>
69__FBSDID("$FreeBSD: head/sys/mips/mips/pmap.c 188507 2009-02-12 01:14:49Z imp $");
70
71#include "opt_ddb.h"
72#include "opt_msgbuf.h"
73#include <sys/param.h>
74#include <sys/systm.h>
75#include <sys/proc.h>
76#include <sys/msgbuf.h>
77#include <sys/vmmeter.h>
78#include <sys/mman.h>
79
80#include <vm/vm.h>
81#include <vm/vm_param.h>
82#include <sys/lock.h>
83#include <sys/mutex.h>
84#include <vm/vm_kern.h>
85#include <vm/vm_page.h>
86#include <vm/vm_map.h>
87#include <vm/vm_object.h>
88#include <vm/vm_extern.h>
89#include <vm/vm_pageout.h>
90#include <vm/vm_pager.h>
91#include <vm/uma.h>
92#include <sys/pcpu.h>
93#include <sys/sched.h>
94#ifdef SMP
95#include <sys/smp.h>
96#endif
97
98#include <machine/cache.h>
99#include <machine/pltfm.h>
100#include <machine/md_var.h>
101
102#if defined(DIAGNOSTIC)
103#define	PMAP_DIAGNOSTIC
104#endif
105
106#undef PMAP_DEBUG
107
108#ifndef PMAP_SHPGPERPROC
109#define	PMAP_SHPGPERPROC 200
110#endif
111
112#if !defined(PMAP_DIAGNOSTIC)
113#define	PMAP_INLINE __inline
114#else
115#define	PMAP_INLINE
116#endif
117
118/*
119 * Get PDEs and PTEs for user/kernel address space
120 */
121#define	pmap_pde(m, v)	       (&((m)->pm_segtab[(vm_offset_t)(v) >> SEGSHIFT]))
122#define	segtab_pde(m, v)	(m[(vm_offset_t)(v) >> SEGSHIFT])
123
124#define	pmap_pte_w(pte)		((*(int *)pte & PTE_W) != 0)
125#define	pmap_pde_v(pte)		((*(int *)pte) != 0)
126#define	pmap_pte_m(pte)		((*(int *)pte & PTE_M) != 0)
127#define	pmap_pte_v(pte)		((*(int *)pte & PTE_V) != 0)
128
129#define	pmap_pte_set_w(pte, v)	((v)?(*(int *)pte |= PTE_W):(*(int *)pte &= ~PTE_W))
130#define	pmap_pte_set_prot(pte, v) ((*(int *)pte &= ~PG_PROT), (*(int *)pte |= (v)))
131
132#define	MIPS_SEGSIZE		(1L << SEGSHIFT)
133#define	mips_segtrunc(va)	((va) & ~(MIPS_SEGSIZE-1))
134#define	pmap_TLB_invalidate_all() MIPS_TBIAP()
135#define	pmap_va_asid(pmap, va)	((va) | ((pmap)->pm_asid[PCPU_GET(cpuid)].asid << VMTLB_PID_SHIFT))
136#define	is_kernel_pmap(x)	((x) == kernel_pmap)
137
138static struct pmap kernel_pmap_store;
139pmap_t kernel_pmap;
140pd_entry_t *kernel_segmap;
141
142vm_offset_t avail_start;	/* PA of first available physical page */
143vm_offset_t avail_end;		/* PA of last available physical page */
144vm_offset_t virtual_avail;	/* VA of first avail page (after kernel bss) */
145vm_offset_t virtual_end;	/* VA of last avail page (end of kernel AS) */
146
147static int nkpt;
148unsigned pmap_max_asid;		/* max ASID supported by the system */
149
150
151#define	PMAP_ASID_RESERVED	0
152
153
154vm_offset_t kernel_vm_end;
155
156static void pmap_asid_alloc(pmap_t pmap);
157
158/*
159 * Data for the pv entry allocation mechanism
160 */
161static uma_zone_t pvzone;
162static struct vm_object pvzone_obj;
163static int pv_entry_count = 0, pv_entry_max = 0, pv_entry_high_water = 0;
164int pmap_pagedaemon_waken = 0;
165
166struct fpage fpages_shared[FPAGES_SHARED];
167
168struct sysmaps sysmaps_pcpu[MAXCPU];
169
170static PMAP_INLINE void free_pv_entry(pv_entry_t pv);
171static pv_entry_t get_pv_entry(pmap_t locked_pmap);
172static __inline void pmap_changebit(vm_page_t m, int bit, boolean_t setem);
173
174static int pmap_remove_pte(struct pmap *pmap, pt_entry_t *ptq, vm_offset_t va);
175static void pmap_remove_page(struct pmap *pmap, vm_offset_t va);
176static void pmap_remove_entry(struct pmap *pmap, vm_page_t m, vm_offset_t va);
177static boolean_t pmap_testbit(vm_page_t m, int bit);
178static void
179pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t mpte,
180    vm_page_t m, boolean_t wired);
181
182static vm_page_t pmap_allocpte(pmap_t pmap, vm_offset_t va, int flags);
183
184static vm_page_t _pmap_allocpte(pmap_t pmap, unsigned ptepindex, int flags);
185static int pmap_unuse_pt(pmap_t, vm_offset_t, vm_page_t);
186static int init_pte_prot(vm_offset_t va, vm_page_t m, vm_prot_t prot);
187static void pmap_TLB_invalidate_kernel(vm_offset_t);
188static void pmap_TLB_update_kernel(vm_offset_t, pt_entry_t);
189static void pmap_init_fpage(void);
190
191#ifdef SMP
192static void pmap_invalidate_page_action(void *arg);
193static void pmap_invalidate_all_action(void *arg);
194static void pmap_update_page_action(void *arg);
195
196#endif
197
198struct local_sysmaps {
199	struct mtx lock;
200	pt_entry_t CMAP1;
201	pt_entry_t CMAP2;
202	caddr_t CADDR1;
203	caddr_t CADDR2;
204	uint16_t valid1, valid2;
205};
206
207/* This structure is for large memory
208 * above 512Meg. We can't (in 32 bit mode)
209 * just use the direct mapped MIPS_CACHED_TO_PHYS()
210 * macros since we can't see the memory and must
211 * map it in when we need to access it. In 64
212 * bit mode this goes away.
213 */
214static struct local_sysmaps sysmap_lmem[MAXCPU];
215caddr_t virtual_sys_start = (caddr_t)0;
216
217pd_entry_t
218pmap_segmap(pmap_t pmap, vm_offset_t va)
219{
220	if (pmap->pm_segtab)
221		return (pmap->pm_segtab[((vm_offset_t)(va) >> SEGSHIFT)]);
222	else
223		return ((pd_entry_t)0);
224}
225
226/*
227 *	Routine:	pmap_pte
228 *	Function:
229 *		Extract the page table entry associated
230 *		with the given map/virtual_address pair.
231 */
232pt_entry_t *
233pmap_pte(pmap_t pmap, vm_offset_t va)
234{
235	pt_entry_t *pdeaddr;
236
237	if (pmap) {
238		pdeaddr = (pt_entry_t *)pmap_segmap(pmap, va);
239		if (pdeaddr) {
240			return pdeaddr + vad_to_pte_offset(va);
241		}
242	}
243	return ((pt_entry_t *)0);
244}
245
246
247vm_offset_t
248pmap_steal_memory(vm_size_t size)
249{
250	vm_size_t bank_size;
251	vm_offset_t pa, va;
252
253	size = round_page(size);
254
255	bank_size = phys_avail[1] - phys_avail[0];
256	while (size > bank_size) {
257		int i;
258
259		for (i = 0; phys_avail[i + 2]; i += 2) {
260			phys_avail[i] = phys_avail[i + 2];
261			phys_avail[i + 1] = phys_avail[i + 3];
262		}
263		phys_avail[i] = 0;
264		phys_avail[i + 1] = 0;
265		if (!phys_avail[0])
266			panic("pmap_steal_memory: out of memory");
267		bank_size = phys_avail[1] - phys_avail[0];
268	}
269
270	pa = phys_avail[0];
271	phys_avail[0] += size;
272	if (pa >= MIPS_KSEG0_LARGEST_PHYS) {
273		panic("Out of memory below 512Meg?");
274	}
275	va = MIPS_PHYS_TO_CACHED(pa);
276	bzero((caddr_t)va, size);
277	return va;
278}
279
280/*
281 *	Bootstrap the system enough to run with virtual memory.  This
282 * assumes that the phys_avail array has been initialized.
283 */
284void
285pmap_bootstrap(void)
286{
287	pt_entry_t *pgtab;
288	pt_entry_t *pte;
289	int i, j;
290	int memory_larger_than_512meg = 0;
291
292	/* Sort. */
293again:
294	for (i = 0; phys_avail[i + 1] != 0; i += 2) {
295		if (phys_avail[i + 1] >= MIPS_KSEG0_LARGEST_PHYS) {
296			memory_larger_than_512meg++;
297		}
298		if (i < 2)
299			continue;
300		if (phys_avail[i - 2] > phys_avail[i]) {
301			vm_paddr_t ptemp[2];
302
303
304			ptemp[0] = phys_avail[i + 0];
305			ptemp[1] = phys_avail[i + 1];
306
307			phys_avail[i + 0] = phys_avail[i - 2];
308			phys_avail[i + 1] = phys_avail[i - 1];
309
310			phys_avail[i - 2] = ptemp[0];
311			phys_avail[i - 1] = ptemp[1];
312			goto again;
313		}
314	}
315
316	if (bootverbose) {
317		printf("Physical memory chunk(s):\n");
318		for (i = 0; phys_avail[i + 1] != 0; i += 2) {
319			vm_paddr_t size;
320
321			size = phys_avail[i + 1] - phys_avail[i];
322			printf("%#08jx - %#08jx, %ju bytes (%ju pages)\n",
323			    (uintmax_t) phys_avail[i],
324			    (uintmax_t) phys_avail[i + 1] - 1,
325			    (uintmax_t) size, (uintmax_t) size / PAGE_SIZE);
326		}
327	}
328	/*
329	 * Steal the message buffer from the beginning of memory.
330	 */
331	msgbufp = (struct msgbuf *)pmap_steal_memory(MSGBUF_SIZE);
332	msgbufinit(msgbufp, MSGBUF_SIZE);
333
334	/*
335	 * Steal thread0 kstack.
336	 */
337	kstack0 = pmap_steal_memory(KSTACK_PAGES << PAGE_SHIFT);
338
339
340	virtual_avail = VM_MIN_KERNEL_ADDRESS + VM_KERNEL_ALLOC_OFFSET;
341	virtual_end = VM_MAX_KERNEL_ADDRESS;
342
343	/*
344	 * Steal some virtual space that will not be in kernel_segmap. This
345	 * va memory space will be used to map in kernel pages that are
346	 * outside the 512Meg region. Note that we only do this steal when
347	 * we do have memory in this region, that way for systems with
348	 * smaller memory we don't "steal" any va ranges :-)
349	 */
350	if (memory_larger_than_512meg) {
351		for (i = 0; i < MAXCPU; i++) {
352			sysmap_lmem[i].CMAP1 = PTE_G;
353			sysmap_lmem[i].CMAP2 = PTE_G;
354			sysmap_lmem[i].CADDR1 = (caddr_t)virtual_avail;
355			virtual_avail += PAGE_SIZE;
356			sysmap_lmem[i].CADDR2 = (caddr_t)virtual_avail;
357			virtual_avail += PAGE_SIZE;
358			sysmap_lmem[i].valid1 = sysmap_lmem[i].valid2 = 0;
359			PMAP_LGMEM_LOCK_INIT(&sysmap_lmem[i]);
360		}
361	}
362	virtual_sys_start = (caddr_t)virtual_avail;
363	/*
364	 * Allocate segment table for the kernel
365	 */
366	kernel_segmap = (pd_entry_t *)pmap_steal_memory(PAGE_SIZE);
367
368	/*
369	 * Allocate second level page tables for the kernel
370	 */
371	nkpt = NKPT;
372	if (memory_larger_than_512meg) {
373		/*
374		 * If we have a large memory system we CANNOT afford to hit
375		 * pmap_growkernel() and allocate memory. Since we MAY end
376		 * up with a page that is NOT mappable. For that reason we
377		 * up front grab more. Normall NKPT is 120 (YMMV see pmap.h)
378		 * this gives us 480meg of kernel virtual addresses at the
379		 * cost of 120 pages (each page gets us 4 Meg). Since the
380		 * kernel starts at virtual_avail, we can use this to
381		 * calculate how many entris are left from there to the end
382		 * of the segmap, we want to allocate all of it, which would
383		 * be somewhere above 0xC0000000 - 0xFFFFFFFF which results
384		 * in about 256 entries or so instead of the 120.
385		 */
386		nkpt = (PAGE_SIZE / sizeof(pd_entry_t)) - (virtual_avail >> SEGSHIFT);
387	}
388	pgtab = (pt_entry_t *)pmap_steal_memory(PAGE_SIZE * nkpt);
389
390	/*
391	 * The R[4-7]?00 stores only one copy of the Global bit in the
392	 * translation lookaside buffer for each 2 page entry. Thus invalid
393	 * entrys must have the Global bit set so when Entry LO and Entry HI
394	 * G bits are anded together they will produce a global bit to store
395	 * in the tlb.
396	 */
397	for (i = 0, pte = pgtab; i < (nkpt * NPTEPG); i++, pte++)
398		*pte = PTE_G;
399
400	printf("Va=0x%x Ve=%x\n", virtual_avail, virtual_end);
401	/*
402	 * The segment table contains the KVA of the pages in the second
403	 * level page table.
404	 */
405	printf("init kernel_segmap va >> = %d nkpt:%d\n",
406	    (virtual_avail >> SEGSHIFT),
407	    nkpt);
408	for (i = 0, j = (virtual_avail >> SEGSHIFT); i < nkpt; i++, j++)
409		kernel_segmap[j] = (pd_entry_t)(pgtab + (i * NPTEPG));
410
411	avail_start = phys_avail[0];
412	for (i = 0; phys_avail[i + 2]; i += 2);
413	avail_end = phys_avail[i + 1];
414
415	/*
416	 * The kernel's pmap is statically allocated so we don't have to use
417	 * pmap_create, which is unlikely to work correctly at this part of
418	 * the boot sequence (XXX and which no longer exists).
419	 */
420	kernel_pmap = &kernel_pmap_store;
421
422	PMAP_LOCK_INIT(kernel_pmap);
423	kernel_pmap->pm_segtab = kernel_segmap;
424	kernel_pmap->pm_active = ~0;
425	TAILQ_INIT(&kernel_pmap->pm_pvlist);
426	printf("avail_start:0x%x avail_end:0x%x\n",
427	    avail_start, avail_end);
428
429	kernel_pmap->pm_asid[PCPU_GET(cpuid)].asid = PMAP_ASID_RESERVED;
430	kernel_pmap->pm_asid[PCPU_GET(cpuid)].gen = 0;
431	pmap_max_asid = VMNUM_PIDS;
432	MachSetPID(0);
433}
434
435/*
436 * Initialize a vm_page's machine-dependent fields.
437 */
438void
439pmap_page_init(vm_page_t m)
440{
441
442	TAILQ_INIT(&m->md.pv_list);
443	m->md.pv_list_count = 0;
444	m->md.pv_flags = 0;
445}
446
447/*
448 *	Initialize the pmap module.
449 *	Called by vm_init, to initialize any structures that the pmap
450 *	system needs to map virtual memory.
451 *	pmap_init has been enhanced to support in a fairly consistant
452 *	way, discontiguous physical memory.
453 */
454void
455pmap_init(void)
456{
457
458	if (need_wired_tlb_page_pool)
459		pmap_init_fpage();
460	/*
461	 * Initialize the address space (zone) for the pv entries.  Set a
462	 * high water mark so that the system can recover from excessive
463	 * numbers of pv entries.
464	 */
465	pvzone = uma_zcreate("PV ENTRY", sizeof(struct pv_entry), NULL, NULL,
466	    NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_VM | UMA_ZONE_NOFREE);
467	pv_entry_max = PMAP_SHPGPERPROC * maxproc + cnt.v_page_count;
468	pv_entry_high_water = 9 * (pv_entry_max / 10);
469	uma_zone_set_obj(pvzone, &pvzone_obj, pv_entry_max);
470}
471
472/***************************************************
473 * Low level helper routines.....
474 ***************************************************/
475
476#if defined(PMAP_DIAGNOSTIC)
477
478/*
479 * This code checks for non-writeable/modified pages.
480 * This should be an invalid condition.
481 */
482static int
483pmap_nw_modified(pt_entry_t pte)
484{
485	if ((pte & (PTE_M | PTE_RO)) == (PTE_M | PTE_RO))
486		return (1);
487	else
488		return (0);
489}
490
491#endif
492
493static void
494pmap_invalidate_all(pmap_t pmap)
495{
496#ifdef SMP
497	smp_rendezvous(0, pmap_invalidate_all_action, 0, (void *)pmap);
498}
499
500static void
501pmap_invalidate_all_action(void *arg)
502{
503	pmap_t pmap = (pmap_t)arg;
504
505#endif
506
507	if (pmap->pm_active & PCPU_GET(cpumask)) {
508		pmap_TLB_invalidate_all();
509	} else
510		pmap->pm_asid[PCPU_GET(cpuid)].gen = 0;
511}
512
513struct pmap_invalidate_page_arg {
514	pmap_t pmap;
515	vm_offset_t va;
516};
517
518static __inline void
519pmap_invalidate_page(pmap_t pmap, vm_offset_t va)
520{
521#ifdef SMP
522	struct pmap_invalidate_page_arg arg;
523
524	arg.pmap = pmap;
525	arg.va = va;
526
527	smp_rendezvous(0, pmap_invalidate_page_action, 0, (void *)&arg);
528}
529
530static void
531pmap_invalidate_page_action(void *arg)
532{
533	pmap_t pmap = ((struct pmap_invalidate_page_arg *)arg)->pmap;
534	vm_offset_t va = ((struct pmap_invalidate_page_arg *)arg)->va;
535
536#endif
537
538	if (is_kernel_pmap(pmap)) {
539		pmap_TLB_invalidate_kernel(va);
540		return;
541	}
542	if (pmap->pm_asid[PCPU_GET(cpuid)].gen != PCPU_GET(asid_generation))
543		return;
544	else if (!(pmap->pm_active & PCPU_GET(cpumask))) {
545		pmap->pm_asid[PCPU_GET(cpuid)].gen = 0;
546		return;
547	}
548	va = pmap_va_asid(pmap, (va & ~PGOFSET));
549	mips_TBIS(va);
550}
551
552static void
553pmap_TLB_invalidate_kernel(vm_offset_t va)
554{
555	u_int32_t pid;
556
557	MachTLBGetPID(pid);
558	va = va | (pid << VMTLB_PID_SHIFT);
559	mips_TBIS(va);
560}
561
562struct pmap_update_page_arg {
563	pmap_t pmap;
564	vm_offset_t va;
565	pt_entry_t pte;
566};
567
568void
569pmap_update_page(pmap_t pmap, vm_offset_t va, pt_entry_t pte)
570{
571#ifdef SMP
572	struct pmap_update_page_arg arg;
573
574	arg.pmap = pmap;
575	arg.va = va;
576	arg.pte = pte;
577
578	smp_rendezvous(0, pmap_update_page_action, 0, (void *)&arg);
579}
580
581static void
582pmap_update_page_action(void *arg)
583{
584	pmap_t pmap = ((struct pmap_update_page_arg *)arg)->pmap;
585	vm_offset_t va = ((struct pmap_update_page_arg *)arg)->va;
586	pt_entry_t pte = ((struct pmap_update_page_arg *)arg)->pte;
587
588#endif
589	if (is_kernel_pmap(pmap)) {
590		pmap_TLB_update_kernel(va, pte);
591		return;
592	}
593	if (pmap->pm_asid[PCPU_GET(cpuid)].gen != PCPU_GET(asid_generation))
594		return;
595	else if (!(pmap->pm_active & PCPU_GET(cpumask))) {
596		pmap->pm_asid[PCPU_GET(cpuid)].gen = 0;
597		return;
598	}
599	va = pmap_va_asid(pmap, va);
600	MachTLBUpdate(va, pte);
601}
602
603static void
604pmap_TLB_update_kernel(vm_offset_t va, pt_entry_t pte)
605{
606	u_int32_t pid;
607
608	MachTLBGetPID(pid);
609	va = va | (pid << VMTLB_PID_SHIFT);
610
611	MachTLBUpdate(va, pte);
612}
613
614/*
615 *	Routine:	pmap_extract
616 *	Function:
617 *		Extract the physical page address associated
618 *		with the given map/virtual_address pair.
619 */
620vm_paddr_t
621pmap_extract(pmap_t pmap, vm_offset_t va)
622{
623	pt_entry_t *pte;
624	vm_offset_t retval = 0;
625
626	PMAP_LOCK(pmap);
627	pte = pmap_pte(pmap, va);
628	if (pte) {
629		retval = mips_tlbpfn_to_paddr(*pte) | (va & PAGE_MASK);
630	}
631	PMAP_UNLOCK(pmap);
632	return retval;
633}
634
635/*
636 *	Routine:	pmap_extract_and_hold
637 *	Function:
638 *		Atomically extract and hold the physical page
639 *		with the given pmap and virtual address pair
640 *		if that mapping permits the given protection.
641 */
642vm_page_t
643pmap_extract_and_hold(pmap_t pmap, vm_offset_t va, vm_prot_t prot)
644{
645	pt_entry_t pte;
646	vm_page_t m;
647
648	m = NULL;
649	vm_page_lock_queues();
650	PMAP_LOCK(pmap);
651
652	pte = *pmap_pte(pmap, va);
653	if (pte != 0 && pmap_pte_v(&pte) &&
654	    ((pte & PTE_RW) || (prot & VM_PROT_WRITE) == 0)) {
655		m = PHYS_TO_VM_PAGE(mips_tlbpfn_to_paddr(pte));
656		vm_page_hold(m);
657	}
658	vm_page_unlock_queues();
659	PMAP_UNLOCK(pmap);
660	return (m);
661}
662
663/***************************************************
664 * Low level mapping routines.....
665 ***************************************************/
666
667/*
668 * add a wired page to the kva
669 */
670 /* PMAP_INLINE */ void
671pmap_kenter(vm_offset_t va, vm_paddr_t pa)
672{
673	register pt_entry_t *pte;
674	pt_entry_t npte, opte;
675
676#ifdef PMAP_DEBUG
677	printf("pmap_kenter:  va: 0x%08x -> pa: 0x%08x\n", va, pa);
678#endif
679	npte = mips_paddr_to_tlbpfn(pa) | PTE_RW | PTE_V | PTE_G | PTE_W;
680
681	if (is_cacheable_mem(pa))
682		npte |= PTE_CACHE;
683	else
684		npte |= PTE_UNCACHED;
685
686	pte = pmap_pte(kernel_pmap, va);
687	opte = *pte;
688	*pte = npte;
689
690	pmap_update_page(kernel_pmap, va, npte);
691}
692
693/*
694 * remove a page from the kernel pagetables
695 */
696 /* PMAP_INLINE */ void
697pmap_kremove(vm_offset_t va)
698{
699	register pt_entry_t *pte;
700
701	pte = pmap_pte(kernel_pmap, va);
702	*pte = PTE_G;
703	pmap_invalidate_page(kernel_pmap, va);
704}
705
706/*
707 *	Used to map a range of physical addresses into kernel
708 *	virtual address space.
709 *
710 *	The value passed in '*virt' is a suggested virtual address for
711 *	the mapping. Architectures which can support a direct-mapped
712 *	physical to virtual region can return the appropriate address
713 *	within that region, leaving '*virt' unchanged. Other
714 *	architectures should map the pages starting at '*virt' and
715 *	update '*virt' with the first usable address after the mapped
716 *	region.
717 */
718vm_offset_t
719pmap_map(vm_offset_t *virt, vm_offset_t start, vm_offset_t end, int prot)
720{
721	vm_offset_t va, sva;
722
723	va = sva = *virt;
724	while (start < end) {
725		pmap_kenter(va, start);
726		va += PAGE_SIZE;
727		start += PAGE_SIZE;
728	}
729	*virt = va;
730	return (sva);
731}
732
733/*
734 * Add a list of wired pages to the kva
735 * this routine is only used for temporary
736 * kernel mappings that do not need to have
737 * page modification or references recorded.
738 * Note that old mappings are simply written
739 * over.  The page *must* be wired.
740 */
741void
742pmap_qenter(vm_offset_t va, vm_page_t *m, int count)
743{
744	int i;
745
746	for (i = 0; i < count; i++) {
747		pmap_kenter(va, VM_PAGE_TO_PHYS(m[i]));
748		va += PAGE_SIZE;
749	}
750}
751
752/*
753 * this routine jerks page mappings from the
754 * kernel -- it is meant only for temporary mappings.
755 */
756void
757pmap_qremove(vm_offset_t va, int count)
758{
759	while (count-- > 0) {
760		pmap_kremove(va);
761		va += PAGE_SIZE;
762	}
763}
764
765/***************************************************
766 * Page table page management routines.....
767 ***************************************************/
768
769/*
770 * floating pages (FPAGES) management routines
771 *
772 * FPAGES are the reserved virtual memory areas which can be
773 * mapped to any physical memory. This gets used typically
774 * in the following functions:
775 *
776 * pmap_zero_page
777 * pmap_copy_page
778 */
779
780/*
781 * Create the floating pages, aka FPAGES!
782 */
783static void
784pmap_init_fpage()
785{
786	vm_offset_t kva;
787	int i, j;
788	struct sysmaps *sysmaps;
789
790	/*
791	 * We allocate a total of (FPAGES*MAXCPU + FPAGES_SHARED + 1) pages
792	 * at first. FPAGES & FPAGES_SHARED should be EVEN Then we'll adjust
793	 * 'kva' to be even-page aligned so that the fpage area can be wired
794	 * in the TLB with a single TLB entry.
795	 */
796	kva = kmem_alloc_nofault(kernel_map,
797	    (FPAGES * MAXCPU + 1 + FPAGES_SHARED) * PAGE_SIZE);
798	if ((void *)kva == NULL)
799		panic("pmap_init_fpage: fpage allocation failed");
800
801	/*
802	 * Make up start at an even page number so we can wire down the
803	 * fpage area in the tlb with a single tlb entry.
804	 */
805	if ((((vm_offset_t)kva) >> PGSHIFT) & 1) {
806		/*
807		 * 'kva' is not even-page aligned. Adjust it and free the
808		 * first page which is unused.
809		 */
810		kmem_free(kernel_map, (vm_offset_t)kva, NBPG);
811		kva = ((vm_offset_t)kva) + NBPG;
812	} else {
813		/*
814		 * 'kva' is even page aligned. We don't need the last page,
815		 * free it.
816		 */
817		kmem_free(kernel_map, ((vm_offset_t)kva) + FSPACE, NBPG);
818	}
819
820	for (i = 0; i < MAXCPU; i++) {
821		sysmaps = &sysmaps_pcpu[i];
822		mtx_init(&sysmaps->lock, "SYSMAPS", NULL, MTX_DEF);
823
824		/* Assign FPAGES pages to the CPU */
825		for (j = 0; j < FPAGES; j++)
826			sysmaps->fp[j].kva = kva + (j) * PAGE_SIZE;
827		kva = ((vm_offset_t)kva) + (FPAGES * PAGE_SIZE);
828	}
829
830	/*
831	 * An additional 2 pages are needed, one for pmap_zero_page_idle()
832	 * and one for coredump. These pages are shared by all cpu's
833	 */
834	fpages_shared[PMAP_FPAGE3].kva = kva;
835	fpages_shared[PMAP_FPAGE_KENTER_TEMP].kva = kva + PAGE_SIZE;
836}
837
838/*
839 * Map the page to the fpage virtual address as specified thru' fpage id
840 */
841vm_offset_t
842pmap_map_fpage(vm_paddr_t pa, struct fpage *fp, boolean_t check_unmaped)
843{
844	vm_offset_t kva;
845	register pt_entry_t *pte;
846	pt_entry_t npte;
847
848	KASSERT(curthread->td_pinned > 0, ("curthread not pinned"));
849	/*
850	 * Check if the fpage is free
851	 */
852	if (fp->state) {
853		if (check_unmaped == TRUE)
854			pmap_unmap_fpage(pa, fp);
855		else
856			panic("pmap_map_fpage: fpage is busy");
857	}
858	fp->state = TRUE;
859	kva = fp->kva;
860
861	npte = mips_paddr_to_tlbpfn(pa) | PTE_RW | PTE_V | PTE_G | PTE_W | PTE_CACHE;
862	pte = pmap_pte(kernel_pmap, kva);
863	*pte = npte;
864
865	pmap_TLB_update_kernel(kva, npte);
866
867	return (kva);
868}
869
870/*
871 * Unmap the page from the fpage virtual address as specified thru' fpage id
872 */
873void
874pmap_unmap_fpage(vm_paddr_t pa, struct fpage *fp)
875{
876	vm_offset_t kva;
877	register pt_entry_t *pte;
878
879	KASSERT(curthread->td_pinned > 0, ("curthread not pinned"));
880	/*
881	 * Check if the fpage is busy
882	 */
883	if (!(fp->state)) {
884		panic("pmap_unmap_fpage: fpage is free");
885	}
886	kva = fp->kva;
887
888	pte = pmap_pte(kernel_pmap, kva);
889	*pte = PTE_G;
890	pmap_TLB_invalidate_kernel(kva);
891
892	fp->state = FALSE;
893
894	/*
895	 * Should there be any flush operation at the end?
896	 */
897}
898
899/*  Revision 1.507
900 *
901 * Simplify the reference counting of page table pages.	 Specifically, use
902 * the page table page's wired count rather than its hold count to contain
903 * the reference count.
904 */
905
906/*
907 * This routine unholds page table pages, and if the hold count
908 * drops to zero, then it decrements the wire count.
909 */
910static int
911_pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m)
912{
913
914	/*
915	 * unmap the page table page
916	 */
917	pmap->pm_segtab[m->pindex] = 0;
918	--pmap->pm_stats.resident_count;
919
920	if (pmap->pm_ptphint == m)
921		pmap->pm_ptphint = NULL;
922
923	/*
924	 * If the page is finally unwired, simply free it.
925	 */
926	vm_page_free_zero(m);
927	atomic_subtract_int(&cnt.v_wire_count, 1);
928	return (1);
929}
930
931static PMAP_INLINE int
932pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m)
933{
934	--m->wire_count;
935	if (m->wire_count == 0)
936		return (_pmap_unwire_pte_hold(pmap, m));
937	else
938		return (0);
939}
940
941/*
942 * After removing a page table entry, this routine is used to
943 * conditionally free the page, and manage the hold/wire counts.
944 */
945static int
946pmap_unuse_pt(pmap_t pmap, vm_offset_t va, vm_page_t mpte)
947{
948	unsigned ptepindex;
949	pd_entry_t pteva;
950
951	if (va >= VM_MAXUSER_ADDRESS)
952		return (0);
953
954	if (mpte == NULL) {
955		ptepindex = (va >> SEGSHIFT);
956		if (pmap->pm_ptphint &&
957		    (pmap->pm_ptphint->pindex == ptepindex)) {
958			mpte = pmap->pm_ptphint;
959		} else {
960			pteva = *pmap_pde(pmap, va);
961			mpte = PHYS_TO_VM_PAGE(MIPS_CACHED_TO_PHYS(pteva));
962			pmap->pm_ptphint = mpte;
963		}
964	}
965	return pmap_unwire_pte_hold(pmap, mpte);
966}
967
968void
969pmap_pinit0(pmap_t pmap)
970{
971	int i;
972
973	PMAP_LOCK_INIT(pmap);
974	pmap->pm_segtab = kernel_segmap;
975	pmap->pm_active = 0;
976	pmap->pm_ptphint = NULL;
977	for (i = 0; i < MAXCPU; i++) {
978		pmap->pm_asid[i].asid = PMAP_ASID_RESERVED;
979		pmap->pm_asid[i].gen = 0;
980	}
981	PCPU_SET(curpmap, pmap);
982	TAILQ_INIT(&pmap->pm_pvlist);
983	bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
984}
985
986/*
987 * Initialize a preallocated and zeroed pmap structure,
988 * such as one in a vmspace structure.
989 */
990int
991pmap_pinit(pmap_t pmap)
992{
993	vm_page_t ptdpg;
994	int i;
995	int req;
996
997	PMAP_LOCK_INIT(pmap);
998
999	req = VM_ALLOC_NOOBJ | VM_ALLOC_NORMAL | VM_ALLOC_WIRED |
1000	    VM_ALLOC_ZERO;
1001
1002#ifdef VM_ALLOC_WIRED_TLB_PG_POOL
1003	if (need_wired_tlb_page_pool)
1004		req |= VM_ALLOC_WIRED_TLB_PG_POOL;
1005#endif
1006	/*
1007	 * allocate the page directory page
1008	 */
1009	ptdpg = vm_page_alloc(NULL, NUSERPGTBLS, req);
1010
1011#if 0
1012	/* I think we can just delete these, now that PG_BUSY is gone */
1013	vm_page_lock_queues();
1014	vm_page_flag_clear(ptdpg, PTE_BUSY);	/* not usually mapped */
1015#endif
1016	ptdpg->valid = VM_PAGE_BITS_ALL;
1017
1018#if 0
1019	vm_page_unlock_queues();
1020#endif
1021
1022	pmap->pm_segtab = (pd_entry_t *)
1023	    MIPS_PHYS_TO_CACHED(VM_PAGE_TO_PHYS(ptdpg));
1024	if ((ptdpg->flags & PG_ZERO) == 0)
1025		bzero(pmap->pm_segtab, PAGE_SIZE);
1026
1027	pmap->pm_active = 0;
1028	pmap->pm_ptphint = NULL;
1029	for (i = 0; i < MAXCPU; i++) {
1030		pmap->pm_asid[i].asid = PMAP_ASID_RESERVED;
1031		pmap->pm_asid[i].gen = 0;
1032	}
1033	TAILQ_INIT(&pmap->pm_pvlist);
1034	bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
1035
1036	return (1);
1037}
1038
1039/*
1040 * this routine is called if the page table page is not
1041 * mapped correctly.
1042 */
1043static vm_page_t
1044_pmap_allocpte(pmap_t pmap, unsigned ptepindex, int flags)
1045{
1046	vm_offset_t pteva, ptepa;
1047	vm_page_t m;
1048	int req;
1049
1050	KASSERT((flags & (M_NOWAIT | M_WAITOK)) == M_NOWAIT ||
1051	    (flags & (M_NOWAIT | M_WAITOK)) == M_WAITOK,
1052	    ("_pmap_allocpte: flags is neither M_NOWAIT nor M_WAITOK"));
1053
1054	req = VM_ALLOC_WIRED | VM_ALLOC_ZERO | VM_ALLOC_NOOBJ;
1055#ifdef VM_ALLOC_WIRED_TLB_PG_POOL
1056	if (need_wired_tlb_page_pool)
1057		req |= VM_ALLOC_WIRED_TLB_PG_POOL;
1058#endif
1059	/*
1060	 * Find or fabricate a new pagetable page
1061	 */
1062	if ((m = vm_page_alloc(NULL, ptepindex, req)) == NULL) {
1063		if (flags & M_WAITOK) {
1064			PMAP_UNLOCK(pmap);
1065			vm_page_unlock_queues();
1066			VM_WAIT;
1067			vm_page_lock_queues();
1068			PMAP_LOCK(pmap);
1069		}
1070		/*
1071		 * Indicate the need to retry.	While waiting, the page
1072		 * table page may have been allocated.
1073		 */
1074		return (NULL);
1075	}
1076	if ((m->flags & PG_ZERO) == 0)
1077		pmap_zero_page(m);
1078
1079	KASSERT(m->queue == PQ_NONE,
1080	    ("_pmap_allocpte: %p->queue != PQ_NONE", m));
1081
1082	/*
1083	 * Map the pagetable page into the process address space, if it
1084	 * isn't already there.
1085	 */
1086
1087	pmap->pm_stats.resident_count++;
1088
1089	ptepa = VM_PAGE_TO_PHYS(m);
1090	pteva = MIPS_PHYS_TO_CACHED(ptepa);
1091	pmap->pm_segtab[ptepindex] = (pd_entry_t)pteva;
1092
1093	/*
1094	 * Set the page table hint
1095	 */
1096	pmap->pm_ptphint = m;
1097
1098	/*
1099	 * Kernel page tables are allocated in pmap_bootstrap() or
1100	 * pmap_growkernel().
1101	 */
1102	if (is_kernel_pmap(pmap))
1103		panic("_pmap_allocpte() called for kernel pmap\n");
1104
1105	m->valid = VM_PAGE_BITS_ALL;
1106	vm_page_flag_clear(m, PG_ZERO);
1107
1108	return (m);
1109}
1110
1111static vm_page_t
1112pmap_allocpte(pmap_t pmap, vm_offset_t va, int flags)
1113{
1114	unsigned ptepindex;
1115	vm_offset_t pteva;
1116	vm_page_t m;
1117
1118	KASSERT((flags & (M_NOWAIT | M_WAITOK)) == M_NOWAIT ||
1119	    (flags & (M_NOWAIT | M_WAITOK)) == M_WAITOK,
1120	    ("pmap_allocpte: flags is neither M_NOWAIT nor M_WAITOK"));
1121
1122	/*
1123	 * Calculate pagetable page index
1124	 */
1125	ptepindex = va >> SEGSHIFT;
1126retry:
1127	/*
1128	 * Get the page directory entry
1129	 */
1130	pteva = (vm_offset_t)pmap->pm_segtab[ptepindex];
1131
1132	/*
1133	 * If the page table page is mapped, we just increment the hold
1134	 * count, and activate it.
1135	 */
1136	if (pteva) {
1137		/*
1138		 * In order to get the page table page, try the hint first.
1139		 */
1140		if (pmap->pm_ptphint &&
1141		    (pmap->pm_ptphint->pindex == ptepindex)) {
1142			m = pmap->pm_ptphint;
1143		} else {
1144			m = PHYS_TO_VM_PAGE(MIPS_CACHED_TO_PHYS(pteva));
1145			pmap->pm_ptphint = m;
1146		}
1147		m->wire_count++;
1148	} else {
1149		/*
1150		 * Here if the pte page isn't mapped, or if it has been
1151		 * deallocated.
1152		 */
1153		m = _pmap_allocpte(pmap, ptepindex, flags);
1154		if (m == NULL && (flags & M_WAITOK))
1155			goto retry;
1156	}
1157	return m;
1158}
1159
1160
1161/***************************************************
1162* Pmap allocation/deallocation routines.
1163 ***************************************************/
1164/*
1165 *  Revision 1.397
1166 *  - Merged pmap_release and pmap_release_free_page.  When pmap_release is
1167 *    called only the page directory page(s) can be left in the pmap pte
1168 *    object, since all page table pages will have been freed by
1169 *    pmap_remove_pages and pmap_remove.  In addition, there can only be one
1170 *    reference to the pmap and the page directory is wired, so the page(s)
1171 *    can never be busy.  So all there is to do is clear the magic mappings
1172 *    from the page directory and free the page(s).
1173 */
1174
1175
1176/*
1177 * Release any resources held by the given physical map.
1178 * Called when a pmap initialized by pmap_pinit is being released.
1179 * Should only be called if the map contains no valid mappings.
1180 */
1181void
1182pmap_release(pmap_t pmap)
1183{
1184	vm_page_t ptdpg;
1185
1186	KASSERT(pmap->pm_stats.resident_count == 0,
1187	    ("pmap_release: pmap resident count %ld != 0",
1188	    pmap->pm_stats.resident_count));
1189
1190	ptdpg = PHYS_TO_VM_PAGE(MIPS_CACHED_TO_PHYS(pmap->pm_segtab));
1191
1192	vm_page_lock_queues();
1193	ptdpg->wire_count--;
1194	atomic_subtract_int(&cnt.v_wire_count, 1);
1195	vm_page_free_zero(ptdpg);
1196	vm_page_unlock_queues();
1197}
1198
1199/*
1200 * grow the number of kernel page table entries, if needed
1201 */
1202void
1203pmap_growkernel(vm_offset_t addr)
1204{
1205	vm_offset_t ptppaddr;
1206	vm_page_t nkpg;
1207	pt_entry_t *pte;
1208	int i, req;
1209
1210	mtx_assert(&kernel_map->system_mtx, MA_OWNED);
1211	if (kernel_vm_end == 0) {
1212		kernel_vm_end = VM_MIN_KERNEL_ADDRESS + VM_KERNEL_ALLOC_OFFSET;
1213		nkpt = 0;
1214		while (segtab_pde(kernel_segmap, kernel_vm_end)) {
1215			kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) &
1216			    ~(PAGE_SIZE * NPTEPG - 1);
1217			nkpt++;
1218			if (kernel_vm_end - 1 >= kernel_map->max_offset) {
1219				kernel_vm_end = kernel_map->max_offset;
1220				break;
1221			}
1222		}
1223	}
1224	addr = (addr + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1);
1225	if (addr - 1 >= kernel_map->max_offset)
1226		addr = kernel_map->max_offset;
1227	while (kernel_vm_end < addr) {
1228		if (segtab_pde(kernel_segmap, kernel_vm_end)) {
1229			kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) &
1230			    ~(PAGE_SIZE * NPTEPG - 1);
1231			if (kernel_vm_end - 1 >= kernel_map->max_offset) {
1232				kernel_vm_end = kernel_map->max_offset;
1233				break;
1234			}
1235			continue;
1236		}
1237		/*
1238		 * This index is bogus, but out of the way
1239		 */
1240		req = VM_ALLOC_INTERRUPT | VM_ALLOC_WIRED | VM_ALLOC_NOOBJ;
1241#ifdef VM_ALLOC_WIRED_TLB_PG_POOL
1242		if (need_wired_tlb_page_pool)
1243			req |= VM_ALLOC_WIRED_TLB_PG_POOL;
1244#endif
1245		nkpg = vm_page_alloc(NULL, nkpt, req);
1246		if (!nkpg)
1247			panic("pmap_growkernel: no memory to grow kernel");
1248
1249		nkpt++;
1250
1251		ptppaddr = VM_PAGE_TO_PHYS(nkpg);
1252		if (ptppaddr >= MIPS_KSEG0_LARGEST_PHYS) {
1253			/*
1254			 * We need to do something here, but I am not sure
1255			 * what. We can access anything in the 0 - 512Meg
1256			 * region, but if we get a page to go in the kernel
1257			 * segmap that is outside of of that we really need
1258			 * to have another mapping beyond the temporary ones
1259			 * I have. Not sure how to do this yet. FIXME FIXME.
1260			 */
1261			panic("Gak, can't handle a k-page table outside of lower 512Meg");
1262		}
1263		pte = (pt_entry_t *)MIPS_PHYS_TO_CACHED(ptppaddr);
1264		segtab_pde(kernel_segmap, kernel_vm_end) = (pd_entry_t)pte;
1265
1266		/*
1267		 * The R[4-7]?00 stores only one copy of the Global bit in
1268		 * the translation lookaside buffer for each 2 page entry.
1269		 * Thus invalid entrys must have the Global bit set so when
1270		 * Entry LO and Entry HI G bits are anded together they will
1271		 * produce a global bit to store in the tlb.
1272		 */
1273		for (i = 0; i < NPTEPG; i++, pte++)
1274			*pte = PTE_G;
1275
1276		kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) &
1277		    ~(PAGE_SIZE * NPTEPG - 1);
1278		if (kernel_vm_end - 1 >= kernel_map->max_offset) {
1279			kernel_vm_end = kernel_map->max_offset;
1280			break;
1281		}
1282	}
1283}
1284
1285/***************************************************
1286* page management routines.
1287 ***************************************************/
1288
1289/*
1290 * free the pv_entry back to the free list
1291 */
1292static PMAP_INLINE void
1293free_pv_entry(pv_entry_t pv)
1294{
1295
1296	pv_entry_count--;
1297	uma_zfree(pvzone, pv);
1298}
1299
1300/*
1301 * get a new pv_entry, allocating a block from the system
1302 * when needed.
1303 * the memory allocation is performed bypassing the malloc code
1304 * because of the possibility of allocations at interrupt time.
1305 */
1306static pv_entry_t
1307get_pv_entry(pmap_t locked_pmap)
1308{
1309	static const struct timeval printinterval = { 60, 0 };
1310	static struct timeval lastprint;
1311	struct vpgqueues *vpq;
1312	pt_entry_t *pte, oldpte;
1313	pmap_t pmap;
1314	pv_entry_t allocated_pv, next_pv, pv;
1315	vm_offset_t va;
1316	vm_page_t m;
1317
1318	PMAP_LOCK_ASSERT(locked_pmap, MA_OWNED);
1319	mtx_assert(&vm_page_queue_mtx, MA_OWNED);
1320	allocated_pv = uma_zalloc(pvzone, M_NOWAIT);
1321	if (allocated_pv != NULL) {
1322		pv_entry_count++;
1323		if (pv_entry_count > pv_entry_high_water)
1324			pagedaemon_wakeup();
1325		else
1326			return (allocated_pv);
1327	}
1328	/*
1329	 * Reclaim pv entries: At first, destroy mappings to inactive
1330	 * pages.  After that, if a pv entry is still needed, destroy
1331	 * mappings to active pages.
1332	 */
1333	if (ratecheck(&lastprint, &printinterval))
1334		printf("Approaching the limit on PV entries, "
1335		    "increase the vm.pmap.shpgperproc tunable.\n");
1336	vpq = &vm_page_queues[PQ_INACTIVE];
1337retry:
1338	TAILQ_FOREACH(m, &vpq->pl, pageq) {
1339		if (m->hold_count || m->busy)
1340			continue;
1341		TAILQ_FOREACH_SAFE(pv, &m->md.pv_list, pv_list, next_pv) {
1342			va = pv->pv_va;
1343			pmap = pv->pv_pmap;
1344			/* Avoid deadlock and lock recursion. */
1345			if (pmap > locked_pmap)
1346				PMAP_LOCK(pmap);
1347			else if (pmap != locked_pmap && !PMAP_TRYLOCK(pmap))
1348				continue;
1349			pmap->pm_stats.resident_count--;
1350			pte = pmap_pte(pmap, va);
1351			KASSERT(pte != NULL, ("pte"));
1352			oldpte = loadandclear((u_int *)pte);
1353			if (is_kernel_pmap(pmap))
1354				*pte = PTE_G;
1355			KASSERT((oldpte & PTE_W) == 0,
1356			    ("wired pte for unwired page"));
1357			if (m->md.pv_flags & PV_TABLE_REF)
1358				vm_page_flag_set(m, PG_REFERENCED);
1359			if (oldpte & PTE_M)
1360				vm_page_dirty(m);
1361			pmap_invalidate_page(pmap, va);
1362			TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist);
1363			m->md.pv_list_count--;
1364			TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
1365			if (TAILQ_EMPTY(&m->md.pv_list)) {
1366				vm_page_flag_clear(m, PG_WRITEABLE);
1367				m->md.pv_flags &= ~(PV_TABLE_REF | PV_TABLE_MOD);
1368			}
1369			pmap_unuse_pt(pmap, va, pv->pv_ptem);
1370			if (pmap != locked_pmap)
1371				PMAP_UNLOCK(pmap);
1372			if (allocated_pv == NULL)
1373				allocated_pv = pv;
1374			else
1375				free_pv_entry(pv);
1376		}
1377	}
1378	if (allocated_pv == NULL) {
1379		if (vpq == &vm_page_queues[PQ_INACTIVE]) {
1380			vpq = &vm_page_queues[PQ_ACTIVE];
1381			goto retry;
1382		}
1383		panic("get_pv_entry: increase the vm.pmap.shpgperproc tunable");
1384	}
1385	return (allocated_pv);
1386}
1387
1388/*
1389 *  Revision 1.370
1390 *
1391 *  Move pmap_collect() out of the machine-dependent code, rename it
1392 *  to reflect its new location, and add page queue and flag locking.
1393 *
1394 *  Notes: (1) alpha, i386, and ia64 had identical implementations
1395 *  of pmap_collect() in terms of machine-independent interfaces;
1396 *  (2) sparc64 doesn't require it; (3) powerpc had it as a TODO.
1397 *
1398 *  MIPS implementation was identical to alpha [Junos 8.2]
1399 */
1400
1401/*
1402 * If it is the first entry on the list, it is actually
1403 * in the header and we must copy the following entry up
1404 * to the header.  Otherwise we must search the list for
1405 * the entry.  In either case we free the now unused entry.
1406 */
1407
1408static void
1409pmap_remove_entry(struct pmap *pmap, vm_page_t m, vm_offset_t va)
1410{
1411	pv_entry_t pv;
1412
1413	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
1414	mtx_assert(&vm_page_queue_mtx, MA_OWNED);
1415	if (m->md.pv_list_count < pmap->pm_stats.resident_count) {
1416		TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
1417			if (pmap == pv->pv_pmap && va == pv->pv_va)
1418				break;
1419		}
1420	} else {
1421		TAILQ_FOREACH(pv, &pmap->pm_pvlist, pv_plist) {
1422			if (va == pv->pv_va)
1423				break;
1424		}
1425	}
1426
1427	KASSERT(pv != NULL, ("pmap_remove_entry: pv not found"));
1428	TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
1429	m->md.pv_list_count--;
1430	if (TAILQ_FIRST(&m->md.pv_list) == NULL)
1431		vm_page_flag_clear(m, PG_WRITEABLE);
1432
1433	TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist);
1434	free_pv_entry(pv);
1435}
1436
1437/*
1438 * Create a pv entry for page at pa for
1439 * (pmap, va).
1440 */
1441static void
1442pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t mpte, vm_page_t m,
1443    boolean_t wired)
1444{
1445
1446	pv_entry_t pv;
1447
1448	pv = get_pv_entry(pmap);
1449	pv->pv_va = va;
1450	pv->pv_pmap = pmap;
1451	pv->pv_ptem = mpte;
1452	pv->pv_wired = wired;
1453
1454	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
1455	mtx_assert(&vm_page_queue_mtx, MA_OWNED);
1456	TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist);
1457	TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
1458	m->md.pv_list_count++;
1459
1460}
1461
1462/*
1463 * pmap_remove_pte: do the things to unmap a page in a process
1464 */
1465static int
1466pmap_remove_pte(struct pmap *pmap, pt_entry_t *ptq, vm_offset_t va)
1467{
1468	pt_entry_t oldpte;
1469	vm_page_t m;
1470	vm_offset_t pa;
1471
1472	mtx_assert(&vm_page_queue_mtx, MA_OWNED);
1473	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
1474
1475	oldpte = loadandclear((u_int *)ptq);
1476	if (is_kernel_pmap(pmap))
1477		*ptq = PTE_G;
1478
1479	if (oldpte & PTE_W)
1480		pmap->pm_stats.wired_count -= 1;
1481
1482	pmap->pm_stats.resident_count -= 1;
1483	pa = mips_tlbpfn_to_paddr(oldpte);
1484
1485	if (page_is_managed(pa)) {
1486		m = PHYS_TO_VM_PAGE(pa);
1487		if (oldpte & PTE_M) {
1488#if defined(PMAP_DIAGNOSTIC)
1489			if (pmap_nw_modified(oldpte)) {
1490				printf(
1491				    "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n",
1492				    va, oldpte);
1493			}
1494#endif
1495			vm_page_dirty(m);
1496		}
1497		if (m->md.pv_flags & PV_TABLE_REF)
1498			vm_page_flag_set(m, PG_REFERENCED);
1499		m->md.pv_flags &= ~(PV_TABLE_REF | PV_TABLE_MOD);
1500
1501		pmap_remove_entry(pmap, m, va);
1502	}
1503	return pmap_unuse_pt(pmap, va, NULL);
1504
1505}
1506
1507/*
1508 * Remove a single page from a process address space
1509 */
1510static void
1511pmap_remove_page(struct pmap *pmap, vm_offset_t va)
1512{
1513	register pt_entry_t *ptq;
1514
1515	mtx_assert(&vm_page_queue_mtx, MA_OWNED);
1516	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
1517	ptq = pmap_pte(pmap, va);
1518
1519	/*
1520	 * if there is no pte for this address, just skip it!!!
1521	 */
1522	if (!ptq || !pmap_pte_v(ptq)) {
1523		return;
1524	}
1525	/*
1526	 * get a local va for mappings for this pmap.
1527	 */
1528	(void)pmap_remove_pte(pmap, ptq, va);
1529	pmap_invalidate_page(pmap, va);
1530
1531	return;
1532}
1533
1534/*
1535 *	Remove the given range of addresses from the specified map.
1536 *
1537 *	It is assumed that the start and end are properly
1538 *	rounded to the page size.
1539 */
1540void
1541pmap_remove(struct pmap *pmap, vm_offset_t sva, vm_offset_t eva)
1542{
1543	vm_offset_t va, nva;
1544
1545	if (pmap == NULL)
1546		return;
1547
1548	if (pmap->pm_stats.resident_count == 0)
1549		return;
1550
1551	vm_page_lock_queues();
1552	PMAP_LOCK(pmap);
1553
1554	/*
1555	 * special handling of removing one page.  a very common operation
1556	 * and easy to short circuit some code.
1557	 */
1558	if ((sva + PAGE_SIZE) == eva) {
1559		pmap_remove_page(pmap, sva);
1560		goto out;
1561	}
1562	for (va = sva; va < eva; va = nva) {
1563		if (!*pmap_pde(pmap, va)) {
1564			nva = mips_segtrunc(va + MIPS_SEGSIZE);
1565			continue;
1566		}
1567		pmap_remove_page(pmap, va);
1568		nva = va + PAGE_SIZE;
1569	}
1570
1571out:
1572	vm_page_unlock_queues();
1573	PMAP_UNLOCK(pmap);
1574}
1575
1576/*
1577 *	Routine:	pmap_remove_all
1578 *	Function:
1579 *		Removes this physical page from
1580 *		all physical maps in which it resides.
1581 *		Reflects back modify bits to the pager.
1582 *
1583 *	Notes:
1584 *		Original versions of this routine were very
1585 *		inefficient because they iteratively called
1586 *		pmap_remove (slow...)
1587 */
1588
1589void
1590pmap_remove_all(vm_page_t m)
1591{
1592	register pv_entry_t pv;
1593	register pt_entry_t *pte, tpte;
1594
1595#if defined(PMAP_DEBUG)
1596	/*
1597	 * XXX This makes pmap_remove_all() illegal for non-managed pages!
1598	 */
1599	if (m->flags & PG_FICTITIOUS) {
1600		panic("pmap_page_protect: illegal for unmanaged page, va: 0x%x", VM_PAGE_TO_PHYS(m));
1601	}
1602#endif
1603	mtx_assert(&vm_page_queue_mtx, MA_OWNED);
1604
1605	if (m->md.pv_flags & PV_TABLE_REF)
1606		vm_page_flag_set(m, PG_REFERENCED);
1607
1608	while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
1609		PMAP_LOCK(pv->pv_pmap);
1610		pv->pv_pmap->pm_stats.resident_count--;
1611
1612		pte = pmap_pte(pv->pv_pmap, pv->pv_va);
1613
1614		tpte = loadandclear((u_int *)pte);
1615		if (is_kernel_pmap(pv->pv_pmap))
1616			*pte = PTE_G;
1617
1618		if (tpte & PTE_W)
1619			pv->pv_pmap->pm_stats.wired_count--;
1620
1621		/*
1622		 * Update the vm_page_t clean and reference bits.
1623		 */
1624		if (tpte & PTE_M) {
1625#if defined(PMAP_DIAGNOSTIC)
1626			if (pmap_nw_modified(tpte)) {
1627				printf(
1628				    "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n",
1629				    pv->pv_va, tpte);
1630			}
1631#endif
1632			vm_page_dirty(m);
1633		}
1634		pmap_invalidate_page(pv->pv_pmap, pv->pv_va);
1635
1636		TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist);
1637		TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
1638		m->md.pv_list_count--;
1639		pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem);
1640		PMAP_UNLOCK(pv->pv_pmap);
1641		free_pv_entry(pv);
1642	}
1643
1644	vm_page_flag_clear(m, PG_WRITEABLE);
1645	m->md.pv_flags &= ~(PV_TABLE_REF | PV_TABLE_MOD);
1646}
1647
1648/*
1649 *	Set the physical protection on the
1650 *	specified range of this map as requested.
1651 */
1652void
1653pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot)
1654{
1655	pt_entry_t *pte;
1656
1657	if (pmap == NULL)
1658		return;
1659
1660	if ((prot & VM_PROT_READ) == VM_PROT_NONE) {
1661		pmap_remove(pmap, sva, eva);
1662		return;
1663	}
1664	if (prot & VM_PROT_WRITE)
1665		return;
1666
1667	vm_page_lock_queues();
1668	PMAP_LOCK(pmap);
1669	while (sva < eva) {
1670		pt_entry_t pbits, obits;
1671		vm_page_t m;
1672		vm_offset_t pa;
1673
1674		/*
1675		 * If segment table entry is empty, skip this segment.
1676		 */
1677		if (!*pmap_pde(pmap, sva)) {
1678			sva = mips_segtrunc(sva + MIPS_SEGSIZE);
1679			continue;
1680		}
1681		/*
1682		 * If pte is invalid, skip this page
1683		 */
1684		pte = pmap_pte(pmap, sva);
1685		if (!pmap_pte_v(pte)) {
1686			sva += PAGE_SIZE;
1687			continue;
1688		}
1689retry:
1690		obits = pbits = *pte;
1691		pa = mips_tlbpfn_to_paddr(pbits);
1692
1693		if (page_is_managed(pa)) {
1694			m = PHYS_TO_VM_PAGE(pa);
1695			if (m->md.pv_flags & PV_TABLE_REF) {
1696				vm_page_flag_set(m, PG_REFERENCED);
1697				m->md.pv_flags &= ~PV_TABLE_REF;
1698			}
1699			if (pbits & PTE_M) {
1700				vm_page_dirty(m);
1701				m->md.pv_flags &= ~PV_TABLE_MOD;
1702			}
1703		}
1704		pbits = (pbits & ~PTE_M) | PTE_RO;
1705
1706		if (pbits != *pte) {
1707			if (!atomic_cmpset_int((u_int *)pte, obits, pbits))
1708				goto retry;
1709			pmap_update_page(pmap, sva, pbits);
1710		}
1711		sva += PAGE_SIZE;
1712	}
1713	vm_page_unlock_queues();
1714	PMAP_UNLOCK(pmap);
1715}
1716
1717/*
1718 *	Insert the given physical page (p) at
1719 *	the specified virtual address (v) in the
1720 *	target physical map with the protection requested.
1721 *
1722 *	If specified, the page will be wired down, meaning
1723 *	that the related pte can not be reclaimed.
1724 *
1725 *	NB:  This is the only routine which MAY NOT lazy-evaluate
1726 *	or lose information.  That is, this routine must actually
1727 *	insert this page into the given map NOW.
1728 */
1729void
1730pmap_enter(pmap_t pmap, vm_offset_t va, vm_prot_t fault_type, vm_page_t m, vm_prot_t prot,
1731    boolean_t wired)
1732{
1733	vm_offset_t pa, opa;
1734	register pt_entry_t *pte;
1735	pt_entry_t origpte, newpte;
1736	vm_page_t mpte, om;
1737	int rw = 0;
1738
1739	if (pmap == NULL)
1740		return;
1741
1742	va &= ~PAGE_MASK;
1743#ifdef PMAP_DIAGNOSTIC
1744	if (va > VM_MAX_KERNEL_ADDRESS)
1745		panic("pmap_enter: toobig");
1746#endif
1747
1748	mpte = NULL;
1749
1750	vm_page_lock_queues();
1751	PMAP_LOCK(pmap);
1752
1753	/*
1754	 * In the case that a page table page is not resident, we are
1755	 * creating it here.
1756	 */
1757	if (va < VM_MAXUSER_ADDRESS) {
1758		mpte = pmap_allocpte(pmap, va, M_WAITOK);
1759	}
1760	pte = pmap_pte(pmap, va);
1761
1762	/*
1763	 * Page Directory table entry not valid, we need a new PT page
1764	 */
1765	if (pte == NULL) {
1766		panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n",
1767		    (void *)pmap->pm_segtab, va);
1768	}
1769	pa = VM_PAGE_TO_PHYS(m);
1770	om = NULL;
1771	origpte = *pte;
1772	opa = mips_tlbpfn_to_paddr(origpte);
1773
1774	/*
1775	 * Mapping has not changed, must be protection or wiring change.
1776	 */
1777	if ((origpte & PTE_V) && (opa == pa)) {
1778		/*
1779		 * Wiring change, just update stats. We don't worry about
1780		 * wiring PT pages as they remain resident as long as there
1781		 * are valid mappings in them. Hence, if a user page is
1782		 * wired, the PT page will be also.
1783		 */
1784		if (wired && ((origpte & PTE_W) == 0))
1785			pmap->pm_stats.wired_count++;
1786		else if (!wired && (origpte & PTE_W))
1787			pmap->pm_stats.wired_count--;
1788
1789#if defined(PMAP_DIAGNOSTIC)
1790		if (pmap_nw_modified(origpte)) {
1791			printf(
1792			    "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n",
1793			    va, origpte);
1794		}
1795#endif
1796
1797		/*
1798		 * Remove extra pte reference
1799		 */
1800		if (mpte)
1801			mpte->wire_count--;
1802
1803		/*
1804		 * We might be turning off write access to the page, so we
1805		 * go ahead and sense modify status.
1806		 */
1807		if (page_is_managed(opa)) {
1808			om = m;
1809		}
1810		goto validate;
1811	}
1812	/*
1813	 * Mapping has changed, invalidate old range and fall through to
1814	 * handle validating new mapping.
1815	 */
1816	if (opa) {
1817		if (origpte & PTE_W)
1818			pmap->pm_stats.wired_count--;
1819
1820		if (page_is_managed(opa)) {
1821			om = PHYS_TO_VM_PAGE(opa);
1822			pmap_remove_entry(pmap, om, va);
1823		}
1824		if (mpte != NULL) {
1825			mpte->wire_count--;
1826			KASSERT(mpte->wire_count > 0,
1827			    ("pmap_enter: missing reference to page table page,"
1828			    " va: 0x%x", va));
1829		}
1830	} else
1831		pmap->pm_stats.resident_count++;
1832
1833	/*
1834	 * Enter on the PV list if part of our managed memory. Note that we
1835	 * raise IPL while manipulating pv_table since pmap_enter can be
1836	 * called at interrupt time.
1837	 */
1838	if ((m->flags & (PG_FICTITIOUS | PG_UNMANAGED)) == 0) {
1839		KASSERT(va < kmi.clean_sva || va >= kmi.clean_eva,
1840		    ("pmap_enter: managed mapping within the clean submap"));
1841		pmap_insert_entry(pmap, va, mpte, m, wired);
1842	}
1843	/*
1844	 * Increment counters
1845	 */
1846	if (wired)
1847		pmap->pm_stats.wired_count++;
1848
1849validate:
1850	rw = init_pte_prot(va, m, prot);
1851
1852#ifdef PMAP_DEBUG
1853	printf("pmap_enter:  va: 0x%08x -> pa: 0x%08x\n", va, pa);
1854#endif
1855	/*
1856	 * Now validate mapping with desired protection/wiring.
1857	 */
1858	newpte = mips_paddr_to_tlbpfn(pa) | rw | PTE_V;
1859
1860	if (is_cacheable_mem(pa))
1861		newpte |= PTE_CACHE;
1862	else
1863		newpte |= PTE_UNCACHED;
1864
1865	if (wired)
1866		newpte |= PTE_W;
1867
1868	if (is_kernel_pmap(pmap)) {
1869	         newpte |= PTE_G;
1870	}
1871
1872	/*
1873	 * if the mapping or permission bits are different, we need to
1874	 * update the pte.
1875	 */
1876	if (origpte != newpte) {
1877		if (origpte & PTE_V) {
1878			*pte = newpte;
1879			if (page_is_managed(opa) && (opa != pa)) {
1880				if (om->md.pv_flags & PV_TABLE_REF)
1881					vm_page_flag_set(om, PG_REFERENCED);
1882				om->md.pv_flags &=
1883				    ~(PV_TABLE_REF | PV_TABLE_MOD);
1884			}
1885			if (origpte & PTE_M) {
1886				KASSERT((origpte & PTE_RW),
1887				    ("pmap_enter: modified page not writable:"
1888				    " va: 0x%x, pte: 0x%lx", va, origpte));
1889				if (page_is_managed(opa))
1890					vm_page_dirty(om);
1891			}
1892		} else {
1893			*pte = newpte;
1894		}
1895	}
1896	pmap_update_page(pmap, va, newpte);
1897
1898	/*
1899	 * Sync I & D caches for executable pages.  Do this only if the the
1900	 * target pmap belongs to the current process.  Otherwise, an
1901	 * unresolvable TLB miss may occur.
1902	 */
1903	if (!is_kernel_pmap(pmap) && (pmap == &curproc->p_vmspace->vm_pmap) &&
1904	    (prot & VM_PROT_EXECUTE)) {
1905		mips_icache_sync_range(va, NBPG);
1906		mips_dcache_wbinv_range(va, NBPG);
1907	}
1908	vm_page_unlock_queues();
1909	PMAP_UNLOCK(pmap);
1910}
1911
1912/*
1913 * this code makes some *MAJOR* assumptions:
1914 * 1. Current pmap & pmap exists.
1915 * 2. Not wired.
1916 * 3. Read access.
1917 * 4. No page table pages.
1918 * but is *MUCH* faster than pmap_enter...
1919 */
1920
1921
1922void
1923pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot)
1924{
1925	pt_entry_t *pte;
1926	vm_offset_t pa;
1927	vm_page_t mpte = NULL;
1928
1929	KASSERT(va < kmi.clean_sva || va >= kmi.clean_eva ||
1930	    (m->flags & (PG_FICTITIOUS | PG_UNMANAGED)) != 0,
1931	    ("pmap_enter_quick: managed mapping within the clean submap"));
1932	mtx_assert(&vm_page_queue_mtx, MA_OWNED);
1933	VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED);
1934	PMAP_LOCK(pmap);
1935	/*
1936	 * In the case that a page table page is not resident, we are
1937	 * creating it here.
1938	 */
1939	if (va < VM_MAXUSER_ADDRESS) {
1940		unsigned ptepindex;
1941		vm_offset_t pteva;
1942
1943		/*
1944		 * Calculate pagetable page index
1945		 */
1946		ptepindex = va >> SEGSHIFT;
1947		if (mpte && (mpte->pindex == ptepindex)) {
1948			mpte->wire_count++;
1949		} else {
1950	retry:
1951			/*
1952			 * Get the page directory entry
1953			 */
1954			pteva = (vm_offset_t)pmap->pm_segtab[ptepindex];
1955
1956			/*
1957			 * If the page table page is mapped, we just
1958			 * increment the hold count, and activate it.
1959			 */
1960			if (pteva) {
1961				if (pmap->pm_ptphint &&
1962				    (pmap->pm_ptphint->pindex == ptepindex)) {
1963					mpte = pmap->pm_ptphint;
1964				} else {
1965					mpte = PHYS_TO_VM_PAGE(MIPS_CACHED_TO_PHYS(pteva));
1966					pmap->pm_ptphint = mpte;
1967				}
1968				mpte->wire_count++;
1969			} else {
1970				mpte = _pmap_allocpte(pmap, ptepindex, M_NOWAIT);
1971				if (mpte == NULL) {
1972					PMAP_UNLOCK(pmap);
1973					vm_page_busy(m);
1974					vm_page_unlock_queues();
1975					VM_OBJECT_UNLOCK(m->object);
1976					VM_WAIT;
1977					VM_OBJECT_LOCK(m->object);
1978					vm_page_lock_queues();
1979					vm_page_wakeup(m);
1980					PMAP_LOCK(pmap);
1981					goto retry;
1982				}
1983			}
1984		}
1985	} else {
1986		mpte = NULL;
1987	}
1988
1989	pte = pmap_pte(pmap, va);
1990	if (pmap_pte_v(pte)) {
1991		if (mpte)
1992			pmap_unwire_pte_hold(pmap, mpte);
1993		PMAP_UNLOCK(pmap);
1994		return;
1995	}
1996	/*
1997	 * Enter on the PV list if part of our managed memory. Note that we
1998	 * raise IPL while manipulating pv_table since pmap_enter can be
1999	 * called at interrupt time.
2000	 */
2001	if ((m->flags & (PG_FICTITIOUS | PG_UNMANAGED)) == 0)
2002		pmap_insert_entry(pmap, va, mpte, m, FALSE);
2003
2004	/*
2005	 * Increment counters
2006	 */
2007	pmap->pm_stats.resident_count++;
2008
2009	pa = VM_PAGE_TO_PHYS(m);
2010
2011	/*
2012	 * Now validate mapping with RO protection
2013	 */
2014	*pte = mips_paddr_to_tlbpfn(pa) | PTE_V;
2015
2016	if (is_cacheable_mem(pa))
2017		*pte |= PTE_CACHE;
2018	else
2019		*pte |= PTE_UNCACHED;
2020
2021	if (is_kernel_pmap(pmap))
2022		*pte |= PTE_G;
2023	else {
2024		*pte |= PTE_RO;
2025		/*
2026		 * Sync I & D caches.  Do this only if the the target pmap
2027		 * belongs to the current process.  Otherwise, an
2028		 * unresolvable TLB miss may occur. */
2029		if (pmap == &curproc->p_vmspace->vm_pmap) {
2030			va &= ~PAGE_MASK;
2031			mips_icache_sync_range(va, NBPG);
2032			mips_dcache_wbinv_range(va, NBPG);
2033		}
2034	}
2035
2036	PMAP_UNLOCK(pmap);
2037	return;
2038}
2039
2040/*
2041 * Make a temporary mapping for a physical address.  This is only intended
2042 * to be used for panic dumps.
2043 */
2044void *
2045pmap_kenter_temporary(vm_paddr_t pa, int i)
2046{
2047	vm_offset_t va;
2048
2049	if (i != 0)
2050		printf("%s: ERROR!!! More than one page of virtual address mapping not supported\n",
2051		    __func__);
2052
2053#ifdef VM_ALLOC_WIRED_TLB_PG_POOL
2054	if (need_wired_tlb_page_pool) {
2055		va = pmap_map_fpage(pa, &fpages_shared[PMAP_FPAGE_KENTER_TEMP],
2056		    TRUE);
2057	} else
2058#endif
2059	if (pa < MIPS_KSEG0_LARGEST_PHYS) {
2060		va = MIPS_PHYS_TO_CACHED(pa);
2061	} else {
2062		int cpu;
2063		struct local_sysmaps *sysm;
2064
2065		cpu = PCPU_GET(cpuid);
2066		sysm = &sysmap_lmem[cpu];
2067		/* Since this is for the debugger, no locks or any other fun */
2068		sysm->CMAP1 = mips_paddr_to_tlbpfn(pa) | PTE_RW | PTE_V | PTE_G | PTE_W | PTE_CACHE;
2069		pmap_TLB_update_kernel((vm_offset_t)sysm->CADDR1, sysm->CMAP1);
2070		sysm->valid1 = 1;
2071		va = (vm_offset_t)sysm->CADDR1;
2072	}
2073	return ((void *)va);
2074}
2075
2076void
2077pmap_kenter_temporary_free(vm_paddr_t pa)
2078{
2079	int cpu;
2080	struct local_sysmaps *sysm;
2081
2082	if (pa < MIPS_KSEG0_LARGEST_PHYS) {
2083		/* nothing to do for this case */
2084		return;
2085	}
2086	cpu = PCPU_GET(cpuid);
2087	sysm = &sysmap_lmem[cpu];
2088	if (sysm->valid1) {
2089		pmap_TLB_invalidate_kernel((vm_offset_t)sysm->CADDR1);
2090		sysm->CMAP1 = 0;
2091		sysm->valid1 = 0;
2092	}
2093}
2094
2095/*
2096 * Moved the code to Machine Independent
2097 *	 vm_map_pmap_enter()
2098 */
2099
2100/*
2101 * Maps a sequence of resident pages belonging to the same object.
2102 * The sequence begins with the given page m_start.  This page is
2103 * mapped at the given virtual address start.  Each subsequent page is
2104 * mapped at a virtual address that is offset from start by the same
2105 * amount as the page is offset from m_start within the object.  The
2106 * last page in the sequence is the page with the largest offset from
2107 * m_start that can be mapped at a virtual address less than the given
2108 * virtual address end.  Not every virtual page between start and end
2109 * is mapped; only those for which a resident page exists with the
2110 * corresponding offset from m_start are mapped.
2111 */
2112void
2113pmap_enter_object(pmap_t pmap, vm_offset_t start, vm_offset_t end,
2114    vm_page_t m_start, vm_prot_t prot)
2115{
2116	vm_page_t m;
2117	vm_pindex_t diff, psize;
2118
2119	psize = atop(end - start);
2120	m = m_start;
2121	while (m != NULL && (diff = m->pindex - m_start->pindex) < psize) {
2122	        /* FIX ME FIX ME - prot is passed in both the
2123		 * the normal spot m, prot but also as the fault_type
2124		 * which we don't use. If we ever use it in pmap_enter
2125		 * we will have to fix this.
2126	         */
2127		pmap_enter(pmap, start + ptoa(diff), prot, m, prot &
2128		    (VM_PROT_READ | VM_PROT_EXECUTE), FALSE);
2129		m = TAILQ_NEXT(m, listq);
2130	}
2131}
2132
2133/*
2134 * pmap_object_init_pt preloads the ptes for a given object
2135 * into the specified pmap.  This eliminates the blast of soft
2136 * faults on process startup and immediately after an mmap.
2137 */
2138void
2139pmap_object_init_pt(pmap_t pmap, vm_offset_t addr,
2140    vm_object_t object, vm_pindex_t pindex, vm_size_t size)
2141{
2142	VM_OBJECT_LOCK_ASSERT(object, MA_OWNED);
2143	KASSERT(object->type == OBJT_DEVICE,
2144	    ("pmap_object_init_pt: non-device object"));
2145}
2146
2147/*
2148 *	Routine:	pmap_change_wiring
2149 *	Function:	Change the wiring attribute for a map/virtual-address
2150 *			pair.
2151 *	In/out conditions:
2152 *			The mapping must already exist in the pmap.
2153 */
2154void
2155pmap_change_wiring(pmap_t pmap, vm_offset_t va, boolean_t wired)
2156{
2157	register pt_entry_t *pte;
2158
2159	if (pmap == NULL)
2160		return;
2161
2162	PMAP_LOCK(pmap);
2163	pte = pmap_pte(pmap, va);
2164
2165	if (wired && !pmap_pte_w(pte))
2166		pmap->pm_stats.wired_count++;
2167	else if (!wired && pmap_pte_w(pte))
2168		pmap->pm_stats.wired_count--;
2169
2170	/*
2171	 * Wiring is not a hardware characteristic so there is no need to
2172	 * invalidate TLB.
2173	 */
2174	pmap_pte_set_w(pte, wired);
2175	PMAP_UNLOCK(pmap);
2176}
2177
2178/*
2179 *	Copy the range specified by src_addr/len
2180 *	from the source map to the range dst_addr/len
2181 *	in the destination map.
2182 *
2183 *	This routine is only advisory and need not do anything.
2184 */
2185
2186void
2187pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr,
2188    vm_size_t len, vm_offset_t src_addr)
2189{
2190}
2191
2192/*
2193 *	pmap_zero_page zeros the specified hardware page by mapping
2194 *	the page into KVM and using bzero to clear its contents.
2195 */
2196void
2197pmap_zero_page(vm_page_t m)
2198{
2199	vm_offset_t va;
2200	vm_paddr_t phys = VM_PAGE_TO_PHYS(m);
2201
2202#ifdef VM_ALLOC_WIRED_TLB_PG_POOL
2203	if (need_wired_tlb_page_pool) {
2204		struct fpage *fp1;
2205		struct sysmaps *sysmaps;
2206
2207		sysmaps = &sysmaps_pcpu[PCPU_GET(cpuid)];
2208		mtx_lock(&sysmaps->lock);
2209		sched_pin();
2210
2211		fp1 = &sysmaps->fp[PMAP_FPAGE1];
2212		va = pmap_map_fpage(phys, fp1, FALSE);
2213		bzero((caddr_t)va, PAGE_SIZE);
2214		pmap_unmap_fpage(phys, fp1);
2215		sched_unpin();
2216		mtx_unlock(&sysmaps->lock);
2217		/*
2218		 * Should you do cache flush?
2219		 */
2220	} else
2221#endif
2222	if (phys < MIPS_KSEG0_LARGEST_PHYS) {
2223
2224		va = MIPS_PHYS_TO_UNCACHED(phys);
2225
2226		bzero((caddr_t)va, PAGE_SIZE);
2227		mips_dcache_wbinv_range(va, PAGE_SIZE);
2228	} else {
2229		int cpu;
2230		struct local_sysmaps *sysm;
2231
2232		cpu = PCPU_GET(cpuid);
2233		sysm = &sysmap_lmem[cpu];
2234		PMAP_LGMEM_LOCK(sysm);
2235		sched_pin();
2236		sysm->CMAP1 = mips_paddr_to_tlbpfn(phys) | PTE_RW | PTE_V | PTE_G | PTE_W | PTE_CACHE;
2237		pmap_TLB_update_kernel((vm_offset_t)sysm->CADDR1, sysm->CMAP1);
2238		sysm->valid1 = 1;
2239		bzero(sysm->CADDR1, PAGE_SIZE);
2240		pmap_TLB_invalidate_kernel((vm_offset_t)sysm->CADDR1);
2241		sysm->CMAP1 = 0;
2242		sysm->valid1 = 0;
2243		sched_unpin();
2244		PMAP_LGMEM_UNLOCK(sysm);
2245	}
2246
2247}
2248
2249/*
2250 *	pmap_zero_page_area zeros the specified hardware page by mapping
2251 *	the page into KVM and using bzero to clear its contents.
2252 *
2253 *	off and size may not cover an area beyond a single hardware page.
2254 */
2255void
2256pmap_zero_page_area(vm_page_t m, int off, int size)
2257{
2258	vm_offset_t va;
2259	vm_paddr_t phys = VM_PAGE_TO_PHYS(m);
2260
2261#ifdef VM_ALLOC_WIRED_TLB_PG_POOL
2262	if (need_wired_tlb_page_pool) {
2263		struct fpage *fp1;
2264		struct sysmaps *sysmaps;
2265
2266		sysmaps = &sysmaps_pcpu[PCPU_GET(cpuid)];
2267		mtx_lock(&sysmaps->lock);
2268		sched_pin();
2269
2270		fp1 = &sysmaps->fp[PMAP_FPAGE1];
2271		va = pmap_map_fpage(phys, fp1, FALSE);
2272		bzero((caddr_t)va + off, size);
2273		pmap_unmap_fpage(phys, fp1);
2274
2275		sched_unpin();
2276		mtx_unlock(&sysmaps->lock);
2277	} else
2278#endif
2279	if (phys < MIPS_KSEG0_LARGEST_PHYS) {
2280		va = MIPS_PHYS_TO_UNCACHED(phys);
2281		bzero((char *)(caddr_t)va + off, size);
2282		mips_dcache_wbinv_range(va + off, size);
2283	} else {
2284		int cpu;
2285		struct local_sysmaps *sysm;
2286
2287		cpu = PCPU_GET(cpuid);
2288		sysm = &sysmap_lmem[cpu];
2289		PMAP_LGMEM_LOCK(sysm);
2290		sched_pin();
2291		sysm->CMAP1 = mips_paddr_to_tlbpfn(phys) | PTE_RW | PTE_V | PTE_G | PTE_W | PTE_CACHE;
2292		pmap_TLB_update_kernel((vm_offset_t)sysm->CADDR1, sysm->CMAP1);
2293		sysm->valid1 = 1;
2294		bzero((char *)sysm->CADDR1 + off, size);
2295		pmap_TLB_invalidate_kernel((vm_offset_t)sysm->CADDR1);
2296		sysm->CMAP1 = 0;
2297		sysm->valid1 = 0;
2298		sched_unpin();
2299		PMAP_LGMEM_UNLOCK(sysm);
2300	}
2301}
2302
2303void
2304pmap_zero_page_idle(vm_page_t m)
2305{
2306	vm_offset_t va;
2307	vm_paddr_t phys = VM_PAGE_TO_PHYS(m);
2308
2309#ifdef VM_ALLOC_WIRED_TLB_PG_POOL
2310	if (need_wired_tlb_page_pool) {
2311		sched_pin();
2312		va = pmap_map_fpage(phys, &fpages_shared[PMAP_FPAGE3], FALSE);
2313		bzero((caddr_t)va, PAGE_SIZE);
2314		pmap_unmap_fpage(phys, &fpages_shared[PMAP_FPAGE3]);
2315		sched_unpin();
2316	} else
2317#endif
2318	if (phys < MIPS_KSEG0_LARGEST_PHYS) {
2319		va = MIPS_PHYS_TO_UNCACHED(phys);
2320		bzero((caddr_t)va, PAGE_SIZE);
2321		mips_dcache_wbinv_range(va, PAGE_SIZE);
2322	} else {
2323		int cpu;
2324		struct local_sysmaps *sysm;
2325
2326		cpu = PCPU_GET(cpuid);
2327		sysm = &sysmap_lmem[cpu];
2328		PMAP_LGMEM_LOCK(sysm);
2329		sched_pin();
2330		sysm->CMAP1 = mips_paddr_to_tlbpfn(phys) | PTE_RW | PTE_V | PTE_G | PTE_W | PTE_CACHE;
2331		pmap_TLB_update_kernel((vm_offset_t)sysm->CADDR1, sysm->CMAP1);
2332		sysm->valid1 = 1;
2333		bzero(sysm->CADDR1, PAGE_SIZE);
2334		pmap_TLB_invalidate_kernel((vm_offset_t)sysm->CADDR1);
2335		sysm->CMAP1 = 0;
2336		sysm->valid1 = 0;
2337		sched_unpin();
2338		PMAP_LGMEM_UNLOCK(sysm);
2339	}
2340
2341}
2342
2343/*
2344 *	pmap_copy_page copies the specified (machine independent)
2345 *	page by mapping the page into virtual memory and using
2346 *	bcopy to copy the page, one machine dependent page at a
2347 *	time.
2348 */
2349void
2350pmap_copy_page(vm_page_t src, vm_page_t dst)
2351{
2352	vm_offset_t va_src, va_dst;
2353	vm_paddr_t phy_src = VM_PAGE_TO_PHYS(src);
2354	vm_paddr_t phy_dst = VM_PAGE_TO_PHYS(dst);
2355
2356
2357#ifdef VM_ALLOC_WIRED_TLB_PG_POOL
2358	if (need_wired_tlb_page_pool) {
2359		struct fpage *fp1, *fp2;
2360		struct sysmaps *sysmaps;
2361
2362		sysmaps = &sysmaps_pcpu[PCPU_GET(cpuid)];
2363		mtx_lock(&sysmaps->lock);
2364		sched_pin();
2365
2366		fp1 = &sysmaps->fp[PMAP_FPAGE1];
2367		fp2 = &sysmaps->fp[PMAP_FPAGE2];
2368
2369		va_src = pmap_map_fpage(phy_src, fp1, FALSE);
2370		va_dst = pmap_map_fpage(phy_dst, fp2, FALSE);
2371
2372		bcopy((caddr_t)va_src, (caddr_t)va_dst, PAGE_SIZE);
2373
2374		pmap_unmap_fpage(phy_src, fp1);
2375		pmap_unmap_fpage(phy_dst, fp2);
2376		sched_unpin();
2377		mtx_unlock(&sysmaps->lock);
2378
2379		/*
2380		 * Should you flush the cache?
2381		 */
2382	} else
2383#endif
2384	{
2385		if ((phy_src < MIPS_KSEG0_LARGEST_PHYS) && (phy_dst < MIPS_KSEG0_LARGEST_PHYS)) {
2386			/* easy case, all can be accessed via KSEG0 */
2387			va_src = MIPS_PHYS_TO_CACHED(phy_src);
2388			va_dst = MIPS_PHYS_TO_CACHED(phy_dst);
2389			bcopy((caddr_t)va_src, (caddr_t)va_dst, PAGE_SIZE);
2390		} else {
2391			int cpu;
2392			struct local_sysmaps *sysm;
2393
2394			cpu = PCPU_GET(cpuid);
2395			sysm = &sysmap_lmem[cpu];
2396			PMAP_LGMEM_LOCK(sysm);
2397			sched_pin();
2398			if (phy_src < MIPS_KSEG0_LARGEST_PHYS) {
2399				/* one side needs mapping - dest */
2400				va_src = MIPS_PHYS_TO_CACHED(phy_src);
2401				sysm->CMAP2 = mips_paddr_to_tlbpfn(phy_dst) | PTE_RW | PTE_V | PTE_G | PTE_W | PTE_CACHE;
2402				pmap_TLB_update_kernel((vm_offset_t)sysm->CADDR2, sysm->CMAP2);
2403				sysm->valid2 = 2;
2404				va_dst = (vm_offset_t)sysm->CADDR2;
2405			} else if (phy_dst < MIPS_KSEG0_LARGEST_PHYS) {
2406				/* one side needs mapping - src */
2407				va_dst = MIPS_PHYS_TO_CACHED(phy_dst);
2408				sysm->CMAP1 = mips_paddr_to_tlbpfn(phy_src) | PTE_RW | PTE_V | PTE_G | PTE_W | PTE_CACHE;
2409				pmap_TLB_update_kernel((vm_offset_t)sysm->CADDR1, sysm->CMAP1);
2410				va_src = (vm_offset_t)sysm->CADDR1;
2411				sysm->valid1 = 1;
2412			} else {
2413				/* all need mapping */
2414				sysm->CMAP1 = mips_paddr_to_tlbpfn(phy_src) | PTE_RW | PTE_V | PTE_G | PTE_W | PTE_CACHE;
2415				sysm->CMAP2 = mips_paddr_to_tlbpfn(phy_dst) | PTE_RW | PTE_V | PTE_G | PTE_W | PTE_CACHE;
2416				pmap_TLB_update_kernel((vm_offset_t)sysm->CADDR1, sysm->CMAP1);
2417				pmap_TLB_update_kernel((vm_offset_t)sysm->CADDR2, sysm->CMAP2);
2418				sysm->valid1 = sysm->valid2 = 1;
2419				va_src = (vm_offset_t)sysm->CADDR1;
2420				va_dst = (vm_offset_t)sysm->CADDR2;
2421			}
2422			bcopy((void *)va_src, (void *)va_dst, PAGE_SIZE);
2423			if (sysm->valid1) {
2424				pmap_TLB_invalidate_kernel((vm_offset_t)sysm->CADDR1);
2425				sysm->CMAP1 = 0;
2426				sysm->valid1 = 0;
2427			}
2428			if (sysm->valid2) {
2429				pmap_TLB_invalidate_kernel((vm_offset_t)sysm->CADDR2);
2430				sysm->CMAP2 = 0;
2431				sysm->valid2 = 0;
2432			}
2433			sched_unpin();
2434			PMAP_LGMEM_UNLOCK(sysm);
2435		}
2436	}
2437}
2438
2439/*
2440 * Returns true if the pmap's pv is one of the first
2441 * 16 pvs linked to from this page.  This count may
2442 * be changed upwards or downwards in the future; it
2443 * is only necessary that true be returned for a small
2444 * subset of pmaps for proper page aging.
2445 */
2446boolean_t
2447pmap_page_exists_quick(pmap_t pmap, vm_page_t m)
2448{
2449	pv_entry_t pv;
2450	int loops = 0;
2451
2452	if (m->flags & PG_FICTITIOUS)
2453		return FALSE;
2454
2455	vm_page_lock_queues();
2456	PMAP_LOCK(pmap);
2457
2458	/*
2459	 * Not found, check current mappings returning immediately if found.
2460	 */
2461	TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
2462		if (pv->pv_pmap == pmap) {
2463			PMAP_UNLOCK(pmap);
2464			vm_page_unlock_queues();
2465			return TRUE;
2466		}
2467		loops++;
2468		if (loops >= 16)
2469			break;
2470	}
2471	PMAP_UNLOCK(pmap);
2472	vm_page_unlock_queues();
2473	return (FALSE);
2474}
2475
2476#define	PMAP_REMOVE_PAGES_CURPROC_ONLY
2477/*
2478 * Remove all pages from specified address space
2479 * this aids process exit speeds.  Also, this code
2480 * is special cased for current process only, but
2481 * can have the more generic (and slightly slower)
2482 * mode enabled.  This is much faster than pmap_remove
2483 * in the case of running down an entire address space.
2484 */
2485void
2486pmap_remove_pages(pmap_t pmap)
2487{
2488	pt_entry_t *pte, tpte;
2489	pv_entry_t pv, npv;
2490	vm_page_t m;
2491
2492#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY
2493	if (pmap != vmspace_pmap(curthread->td_proc->p_vmspace)) {
2494		printf("warning: pmap_remove_pages called with non-current pmap\n");
2495		return;
2496	}
2497#endif
2498
2499	vm_page_lock_queues();
2500	PMAP_LOCK(pmap);
2501	sched_pin();
2502	//XXX need to be TAILQ_FOREACH_SAFE ?
2503	    for (pv = TAILQ_FIRST(&pmap->pm_pvlist);
2504	    pv;
2505	    pv = npv) {
2506
2507		pte = pmap_pte(pv->pv_pmap, pv->pv_va);
2508		if (!pmap_pte_v(pte))
2509			panic("pmap_remove_pages: page on pm_pvlist has no pte\n");
2510		tpte = *pte;
2511
2512/*
2513 * We cannot remove wired pages from a process' mapping at this time
2514 */
2515		if (tpte & PTE_W) {
2516			npv = TAILQ_NEXT(pv, pv_plist);
2517			continue;
2518		}
2519		*pte = is_kernel_pmap(pmap) ? PTE_G : 0;
2520
2521		m = PHYS_TO_VM_PAGE(mips_tlbpfn_to_paddr(tpte));
2522
2523		KASSERT(m < &vm_page_array[vm_page_array_size],
2524		    ("pmap_remove_pages: bad tpte %lx", tpte));
2525
2526		pv->pv_pmap->pm_stats.resident_count--;
2527
2528		/*
2529		 * Update the vm_page_t clean and reference bits.
2530		 */
2531		if (tpte & PTE_M) {
2532			vm_page_dirty(m);
2533		}
2534		npv = TAILQ_NEXT(pv, pv_plist);
2535		TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist);
2536
2537		m->md.pv_list_count--;
2538		TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
2539		if (TAILQ_FIRST(&m->md.pv_list) == NULL) {
2540			vm_page_flag_clear(m, PG_WRITEABLE);
2541		}
2542		pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem);
2543		free_pv_entry(pv);
2544	}
2545	sched_unpin();
2546	pmap_invalidate_all(pmap);
2547	PMAP_UNLOCK(pmap);
2548	vm_page_unlock_queues();
2549}
2550
2551/*
2552 * pmap_testbit tests bits in pte's
2553 * note that the testbit/changebit routines are inline,
2554 * and a lot of things compile-time evaluate.
2555 */
2556static boolean_t
2557pmap_testbit(vm_page_t m, int bit)
2558{
2559	pv_entry_t pv;
2560	pt_entry_t *pte;
2561	boolean_t rv = FALSE;
2562
2563	if (m->flags & PG_FICTITIOUS)
2564		return rv;
2565
2566	if (TAILQ_FIRST(&m->md.pv_list) == NULL)
2567		return rv;
2568
2569	mtx_assert(&vm_page_queue_mtx, MA_OWNED);
2570	TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
2571#if defined(PMAP_DIAGNOSTIC)
2572		if (!pv->pv_pmap) {
2573			printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va);
2574			continue;
2575		}
2576#endif
2577		PMAP_LOCK(pv->pv_pmap);
2578		pte = pmap_pte(pv->pv_pmap, pv->pv_va);
2579		rv = (*pte & bit) != 0;
2580		PMAP_UNLOCK(pv->pv_pmap);
2581		if (rv)
2582			break;
2583	}
2584	return (rv);
2585}
2586
2587/*
2588 * this routine is used to modify bits in ptes
2589 */
2590static __inline void
2591pmap_changebit(vm_page_t m, int bit, boolean_t setem)
2592{
2593	register pv_entry_t pv;
2594	register pt_entry_t *pte;
2595
2596	if (m->flags & PG_FICTITIOUS)
2597		return;
2598
2599	mtx_assert(&vm_page_queue_mtx, MA_OWNED);
2600	/*
2601	 * Loop over all current mappings setting/clearing as appropos If
2602	 * setting RO do we need to clear the VAC?
2603	 */
2604	TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
2605#if defined(PMAP_DIAGNOSTIC)
2606		if (!pv->pv_pmap) {
2607			printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va);
2608			continue;
2609		}
2610#endif
2611
2612		PMAP_LOCK(pv->pv_pmap);
2613		pte = pmap_pte(pv->pv_pmap, pv->pv_va);
2614
2615		if (setem) {
2616			*(int *)pte |= bit;
2617			pmap_update_page(pv->pv_pmap, pv->pv_va, *pte);
2618		} else {
2619			vm_offset_t pbits = *(vm_offset_t *)pte;
2620
2621			if (pbits & bit) {
2622				if (bit == PTE_RW) {
2623					if (pbits & PTE_M) {
2624						vm_page_dirty(m);
2625					}
2626					*(int *)pte = (pbits & ~(PTE_M | PTE_RW)) |
2627					    PTE_RO;
2628				} else {
2629					*(int *)pte = pbits & ~bit;
2630				}
2631				pmap_update_page(pv->pv_pmap, pv->pv_va, *pte);
2632			}
2633		}
2634		PMAP_UNLOCK(pv->pv_pmap);
2635	}
2636	if (!setem && bit == PTE_RW)
2637		vm_page_flag_clear(m, PG_WRITEABLE);
2638}
2639
2640/*
2641 *	pmap_page_wired_mappings:
2642 *
2643 *	Return the number of managed mappings to the given physical page
2644 *	that are wired.
2645 */
2646int
2647pmap_page_wired_mappings(vm_page_t m)
2648{
2649	pv_entry_t pv;
2650	int count;
2651
2652	count = 0;
2653	if ((m->flags & PG_FICTITIOUS) != 0)
2654		return (count);
2655	mtx_assert(&vm_page_queue_mtx, MA_OWNED);
2656	TAILQ_FOREACH(pv, &m->md.pv_list, pv_list)
2657	    if (pv->pv_wired)
2658		count++;
2659	return (count);
2660}
2661
2662/*
2663 * Clear the write and modified bits in each of the given page's mappings.
2664 */
2665void
2666pmap_remove_write(vm_page_t m)
2667{
2668	pv_entry_t pv, npv;
2669	vm_offset_t va;
2670	pt_entry_t *pte;
2671
2672	if ((m->flags & PG_WRITEABLE) == 0)
2673		return;
2674
2675	/*
2676	 * Loop over all current mappings setting/clearing as appropos.
2677	 */
2678	for (pv = TAILQ_FIRST(&m->md.pv_list); pv; pv = npv) {
2679		npv = TAILQ_NEXT(pv, pv_plist);
2680		pte = pmap_pte(pv->pv_pmap, pv->pv_va);
2681
2682		if ((pte == NULL) || !mips_pg_v(*pte))
2683			panic("page on pm_pvlist has no pte\n");
2684
2685		va = pv->pv_va;
2686		pmap_protect(pv->pv_pmap, va, va + PAGE_SIZE,
2687		    VM_PROT_READ | VM_PROT_EXECUTE);
2688	}
2689	vm_page_flag_clear(m, PG_WRITEABLE);
2690}
2691
2692/*
2693 *	pmap_ts_referenced:
2694 *
2695 *	Return the count of reference bits for a page, clearing all of them.
2696 */
2697int
2698pmap_ts_referenced(vm_page_t m)
2699{
2700	if (m->flags & PG_FICTITIOUS)
2701		return (0);
2702
2703	if (m->md.pv_flags & PV_TABLE_REF) {
2704		m->md.pv_flags &= ~PV_TABLE_REF;
2705		return 1;
2706	}
2707	return 0;
2708}
2709
2710/*
2711 *	pmap_is_modified:
2712 *
2713 *	Return whether or not the specified physical page was modified
2714 *	in any physical maps.
2715 */
2716boolean_t
2717pmap_is_modified(vm_page_t m)
2718{
2719	if (m->flags & PG_FICTITIOUS)
2720		return FALSE;
2721
2722	if (m->md.pv_flags & PV_TABLE_MOD)
2723		return TRUE;
2724	else
2725		return pmap_testbit(m, PTE_M);
2726}
2727
2728/* N/C */
2729
2730/*
2731 *	pmap_is_prefaultable:
2732 *
2733 *	Return whether or not the specified virtual address is elgible
2734 *	for prefault.
2735 */
2736boolean_t
2737pmap_is_prefaultable(pmap_t pmap, vm_offset_t addr)
2738{
2739	pt_entry_t *pte;
2740	boolean_t rv;
2741
2742	rv = FALSE;
2743	PMAP_LOCK(pmap);
2744	if (*pmap_pde(pmap, addr)) {
2745		pte = pmap_pte(pmap, addr);
2746		rv = (*pte == 0);
2747	}
2748	PMAP_UNLOCK(pmap);
2749	return (rv);
2750}
2751
2752/*
2753 *	Clear the modify bits on the specified physical page.
2754 */
2755void
2756pmap_clear_modify(vm_page_t m)
2757{
2758	if (m->flags & PG_FICTITIOUS)
2759		return;
2760	mtx_assert(&vm_page_queue_mtx, MA_OWNED);
2761	if (m->md.pv_flags & PV_TABLE_MOD) {
2762		pmap_changebit(m, PTE_M, FALSE);
2763		m->md.pv_flags &= ~PV_TABLE_MOD;
2764	}
2765}
2766
2767/*
2768 *	pmap_clear_reference:
2769 *
2770 *	Clear the reference bit on the specified physical page.
2771 */
2772void
2773pmap_clear_reference(vm_page_t m)
2774{
2775	if (m->flags & PG_FICTITIOUS)
2776		return;
2777
2778	mtx_assert(&vm_page_queue_mtx, MA_OWNED);
2779	if (m->md.pv_flags & PV_TABLE_REF) {
2780		m->md.pv_flags &= ~PV_TABLE_REF;
2781	}
2782}
2783
2784/*
2785 * Miscellaneous support routines follow
2786 */
2787
2788/*
2789 * Map a set of physical memory pages into the kernel virtual
2790 * address space. Return a pointer to where it is mapped. This
2791 * routine is intended to be used for mapping device memory,
2792 * NOT real memory.
2793 */
2794
2795/*
2796 * Map a set of physical memory pages into the kernel virtual
2797 * address space. Return a pointer to where it is mapped. This
2798 * routine is intended to be used for mapping device memory,
2799 * NOT real memory.
2800 */
2801void *
2802pmap_mapdev(vm_offset_t pa, vm_size_t size)
2803{
2804        vm_offset_t va, tmpva, offset;
2805
2806	/*
2807	 * KSEG1 maps only first 512M of phys address space. For
2808	 * pa > 0x20000000 we should make proper mapping * using pmap_kenter.
2809	 */
2810	if (pa + size < MIPS_KSEG0_LARGEST_PHYS)
2811		return (void *)MIPS_PHYS_TO_KSEG1(pa);
2812	else {
2813		offset = pa & PAGE_MASK;
2814		size = roundup(size, PAGE_SIZE);
2815
2816		va = kmem_alloc_nofault(kernel_map, size);
2817		if (!va)
2818			panic("pmap_mapdev: Couldn't alloc kernel virtual memory");
2819		for (tmpva = va; size > 0;) {
2820			pmap_kenter(tmpva, pa);
2821			size -= PAGE_SIZE;
2822			tmpva += PAGE_SIZE;
2823			pa += PAGE_SIZE;
2824		}
2825	}
2826
2827	return ((void *)(va + offset));
2828}
2829
2830void
2831pmap_unmapdev(vm_offset_t va, vm_size_t size)
2832{
2833}
2834
2835/*
2836 * perform the pmap work for mincore
2837 */
2838int
2839pmap_mincore(pmap_t pmap, vm_offset_t addr)
2840{
2841
2842	pt_entry_t *ptep, pte;
2843	vm_page_t m;
2844	int val = 0;
2845
2846	PMAP_LOCK(pmap);
2847	ptep = pmap_pte(pmap, addr);
2848	pte = (ptep != NULL) ? *ptep : 0;
2849	PMAP_UNLOCK(pmap);
2850
2851	if (mips_pg_v(pte)) {
2852		vm_offset_t pa;
2853
2854		val = MINCORE_INCORE;
2855		pa = mips_tlbpfn_to_paddr(pte);
2856		if (!page_is_managed(pa))
2857			return val;
2858
2859		m = PHYS_TO_VM_PAGE(pa);
2860
2861		/*
2862		 * Modified by us
2863		 */
2864		if (pte & PTE_M)
2865			val |= MINCORE_MODIFIED | MINCORE_MODIFIED_OTHER;
2866		/*
2867		 * Modified by someone
2868		 */
2869		else {
2870			vm_page_lock_queues();
2871			if (m->dirty || pmap_is_modified(m))
2872				val |= MINCORE_MODIFIED_OTHER;
2873			vm_page_unlock_queues();
2874		}
2875		/*
2876		 * Referenced by us or someone
2877		 */
2878		vm_page_lock_queues();
2879		if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) {
2880			val |= MINCORE_REFERENCED | MINCORE_REFERENCED_OTHER;
2881			vm_page_flag_set(m, PG_REFERENCED);
2882		}
2883		vm_page_unlock_queues();
2884	}
2885	return val;
2886}
2887
2888void
2889pmap_activate(struct thread *td)
2890{
2891	pmap_t pmap, oldpmap;
2892	struct proc *p = td->td_proc;
2893
2894	critical_enter();
2895
2896	pmap = vmspace_pmap(p->p_vmspace);
2897	oldpmap = PCPU_GET(curpmap);
2898
2899	if (oldpmap)
2900		atomic_clear_32(&oldpmap->pm_active, PCPU_GET(cpumask));
2901	atomic_set_32(&pmap->pm_active, PCPU_GET(cpumask));
2902	pmap_asid_alloc(pmap);
2903	if (td == curthread) {
2904		PCPU_SET(segbase, pmap->pm_segtab);
2905		MachSetPID(pmap->pm_asid[PCPU_GET(cpuid)].asid);
2906	}
2907	PCPU_SET(curpmap, pmap);
2908	critical_exit();
2909}
2910
2911/*
2912 *	Increase the starting virtual address of the given mapping if a
2913 *	different alignment might result in more superpage mappings.
2914 */
2915void
2916pmap_align_superpage(vm_object_t object, vm_ooffset_t offset,
2917    vm_offset_t *addr, vm_size_t size)
2918{
2919	vm_offset_t superpage_offset;
2920
2921	if (size < NBSEG)
2922		return;
2923	if (object != NULL && (object->flags & OBJ_COLORED) != 0)
2924		offset += ptoa(object->pg_color);
2925	superpage_offset = offset & SEGOFSET;
2926	if (size - ((NBSEG - superpage_offset) & SEGOFSET) < NBSEG ||
2927	    (*addr & SEGOFSET) == superpage_offset)
2928		return;
2929	if ((*addr & SEGOFSET) < superpage_offset)
2930		*addr = (*addr & ~SEGOFSET) + superpage_offset;
2931	else
2932		*addr = ((*addr + SEGOFSET) & ~SEGOFSET) + superpage_offset;
2933}
2934
2935int pmap_pid_dump(int pid);
2936
2937int
2938pmap_pid_dump(int pid)
2939{
2940	pmap_t pmap;
2941	struct proc *p;
2942	int npte = 0;
2943	int index;
2944
2945	sx_slock(&allproc_lock);
2946	LIST_FOREACH(p, &allproc, p_list) {
2947		if (p->p_pid != pid)
2948			continue;
2949
2950		if (p->p_vmspace) {
2951			int i, j;
2952
2953			printf("vmspace is %p\n",
2954			       p->p_vmspace);
2955			index = 0;
2956			pmap = vmspace_pmap(p->p_vmspace);
2957			printf("pmap asid:%x generation:%x\n",
2958			       pmap->pm_asid[0].asid,
2959			       pmap->pm_asid[0].gen);
2960			for (i = 0; i < NUSERPGTBLS; i++) {
2961				pd_entry_t *pde;
2962				pt_entry_t *pte;
2963				unsigned base = i << SEGSHIFT;
2964
2965				pde = &pmap->pm_segtab[i];
2966				if (pde && pmap_pde_v(pde)) {
2967					for (j = 0; j < 1024; j++) {
2968						unsigned va = base +
2969						(j << PAGE_SHIFT);
2970
2971						pte = pmap_pte(pmap, va);
2972						if (pte && pmap_pte_v(pte)) {
2973							vm_offset_t pa;
2974							vm_page_t m;
2975
2976							pa = mips_tlbpfn_to_paddr(*pte);
2977							m = PHYS_TO_VM_PAGE(pa);
2978							printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x",
2979							    va, pa,
2980							    m->hold_count,
2981							    m->wire_count,
2982							    m->flags);
2983							npte++;
2984							index++;
2985							if (index >= 2) {
2986								index = 0;
2987								printf("\n");
2988							} else {
2989								printf(" ");
2990							}
2991						}
2992					}
2993				}
2994			}
2995		} else {
2996		  printf("Process pid:%d has no vm_space\n", pid);
2997		}
2998		break;
2999	}
3000	sx_sunlock(&allproc_lock);
3001	return npte;
3002}
3003
3004
3005#if defined(DEBUG)
3006
3007static void pads(pmap_t pm);
3008void pmap_pvdump(vm_offset_t pa);
3009
3010/* print address space of pmap*/
3011static void
3012pads(pmap_t pm)
3013{
3014	unsigned va, i, j;
3015	pt_entry_t *ptep;
3016
3017	if (pm == kernel_pmap)
3018		return;
3019	for (i = 0; i < NPTEPG; i++)
3020		if (pm->pm_segtab[i])
3021			for (j = 0; j < NPTEPG; j++) {
3022				va = (i << SEGSHIFT) + (j << PAGE_SHIFT);
3023				if (pm == kernel_pmap && va < KERNBASE)
3024					continue;
3025				if (pm != kernel_pmap &&
3026				    va >= VM_MAXUSER_ADDRESS)
3027					continue;
3028				ptep = pmap_pte(pm, va);
3029				if (pmap_pte_v(ptep))
3030					printf("%x:%x ", va, *(int *)ptep);
3031			}
3032
3033}
3034
3035void
3036pmap_pvdump(vm_offset_t pa)
3037{
3038	register pv_entry_t pv;
3039	vm_page_t m;
3040
3041	printf("pa %x", pa);
3042	m = PHYS_TO_VM_PAGE(pa);
3043	for (pv = TAILQ_FIRST(&m->md.pv_list); pv;
3044	    pv = TAILQ_NEXT(pv, pv_list)) {
3045		printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va);
3046		pads(pv->pv_pmap);
3047	}
3048	printf(" ");
3049}
3050
3051/* N/C */
3052#endif
3053
3054
3055/*
3056 * Allocate TLB address space tag (called ASID or TLBPID) and return it.
3057 * It takes almost as much or more time to search the TLB for a
3058 * specific ASID and flush those entries as it does to flush the entire TLB.
3059 * Therefore, when we allocate a new ASID, we just take the next number. When
3060 * we run out of numbers, we flush the TLB, increment the generation count
3061 * and start over. ASID zero is reserved for kernel use.
3062 */
3063static void
3064pmap_asid_alloc(pmap)
3065	pmap_t pmap;
3066{
3067	if (pmap->pm_asid[PCPU_GET(cpuid)].asid != PMAP_ASID_RESERVED &&
3068	    pmap->pm_asid[PCPU_GET(cpuid)].gen == PCPU_GET(asid_generation));
3069	else {
3070		if (PCPU_GET(next_asid) == pmap_max_asid) {
3071			MIPS_TBIAP();
3072			PCPU_SET(asid_generation,
3073			    (PCPU_GET(asid_generation) + 1) & ASIDGEN_MASK);
3074			if (PCPU_GET(asid_generation) == 0) {
3075				PCPU_SET(asid_generation, 1);
3076			}
3077			PCPU_SET(next_asid, 1);	/* 0 means invalid */
3078		}
3079		pmap->pm_asid[PCPU_GET(cpuid)].asid = PCPU_GET(next_asid);
3080		pmap->pm_asid[PCPU_GET(cpuid)].gen = PCPU_GET(asid_generation);
3081		PCPU_SET(next_asid, PCPU_GET(next_asid) + 1);
3082	}
3083
3084#ifdef DEBUG
3085	if (pmapdebug & (PDB_FOLLOW | PDB_TLBPID)) {
3086		if (curproc)
3087			printf("pmap_asid_alloc: curproc %d '%s' ",
3088			    curproc->p_pid, curproc->p_comm);
3089		else
3090			printf("pmap_asid_alloc: curproc <none> ");
3091		printf("segtab %p asid %d\n", pmap->pm_segtab,
3092		    pmap->pm_asid[PCPU_GET(cpuid)].asid);
3093	}
3094#endif
3095}
3096
3097int
3098page_is_managed(vm_offset_t pa)
3099{
3100	vm_offset_t pgnum = mips_btop(pa);
3101
3102	if (pgnum >= first_page && (pgnum < (first_page + vm_page_array_size))) {
3103		vm_page_t m;
3104
3105		m = PHYS_TO_VM_PAGE(pa);
3106		if ((m->flags & (PG_FICTITIOUS | PG_UNMANAGED)) == 0)
3107			return 1;
3108	}
3109	return 0;
3110}
3111
3112static int
3113init_pte_prot(vm_offset_t va, vm_page_t m, vm_prot_t prot)
3114{
3115	int rw = 0;
3116
3117	if (!(prot & VM_PROT_WRITE))
3118		rw = PTE_ROPAGE;
3119	else {
3120		if (va >= VM_MIN_KERNEL_ADDRESS) {
3121			/*
3122			 * Don't bother to trap on kernel writes, just
3123			 * record page as dirty.
3124			 */
3125			rw = PTE_RWPAGE;
3126			vm_page_dirty(m);
3127		} else if ((m->md.pv_flags & PV_TABLE_MOD) || m->dirty)
3128			rw = PTE_RWPAGE;
3129		else
3130			rw = PTE_CWPAGE;
3131	}
3132	return rw;
3133}
3134
3135/*
3136 *	pmap_page_is_free:
3137 *
3138 *	Called when a page is freed to allow pmap to clean up
3139 *	any extra state associated with the page.  In this case
3140 *	clear modified/referenced bits.
3141 */
3142void
3143pmap_page_is_free(vm_page_t m)
3144{
3145
3146	m->md.pv_flags = 0;
3147}
3148
3149/*
3150 *	pmap_set_modified:
3151 *
3152 *	Sets the page modified and reference bits for the specified page.
3153 */
3154void
3155pmap_set_modified(vm_offset_t pa)
3156{
3157
3158	PHYS_TO_VM_PAGE(pa)->md.pv_flags |= (PV_TABLE_REF | PV_TABLE_MOD);
3159}
3160
3161#include <machine/db_machdep.h>
3162
3163/*
3164 *  Dump the translation buffer (TLB) in readable form.
3165 */
3166
3167void
3168db_dump_tlb(int first, int last)
3169{
3170	struct tlb tlb;
3171	int tlbno;
3172
3173	tlbno = first;
3174
3175	while (tlbno <= last) {
3176		MachTLBRead(tlbno, &tlb);
3177		if (tlb.tlb_lo0 & PTE_V || tlb.tlb_lo1 & PTE_V) {
3178			printf("TLB %2d vad 0x%08x ", tlbno, (tlb.tlb_hi & 0xffffff00));
3179		} else {
3180			printf("TLB*%2d vad 0x%08x ", tlbno, (tlb.tlb_hi & 0xffffff00));
3181		}
3182		printf("0=0x%08x ", pfn_to_vad(tlb.tlb_lo0));
3183		printf("%c", tlb.tlb_lo0 & PTE_M ? 'M' : ' ');
3184		printf("%c", tlb.tlb_lo0 & PTE_G ? 'G' : ' ');
3185		printf(" atr %x ", (tlb.tlb_lo0 >> 3) & 7);
3186		printf("1=0x%08x ", pfn_to_vad(tlb.tlb_lo1));
3187		printf("%c", tlb.tlb_lo1 & PTE_M ? 'M' : ' ');
3188		printf("%c", tlb.tlb_lo1 & PTE_G ? 'G' : ' ');
3189		printf(" atr %x ", (tlb.tlb_lo1 >> 3) & 7);
3190		printf(" sz=%x pid=%x\n", tlb.tlb_mask,
3191		       (tlb.tlb_hi & 0x000000ff)
3192		       );
3193		tlbno++;
3194	}
3195}
3196
3197#ifdef DDB
3198#include <sys/kernel.h>
3199#include <ddb/ddb.h>
3200
3201DB_SHOW_COMMAND(tlb, ddb_dump_tlb)
3202{
3203	db_dump_tlb(0, num_tlbentries - 1);
3204}
3205
3206#endif
3207
3208/*
3209 *	Routine:	pmap_kextract
3210 *	Function:
3211 *		Extract the physical page address associated
3212 *		virtual address.
3213 */
3214 /* PMAP_INLINE */ vm_offset_t
3215pmap_kextract(vm_offset_t va)
3216{
3217	vm_offset_t pa = 0;
3218
3219	if (va < MIPS_CACHED_MEMORY_ADDR) {
3220		/* user virtual address */
3221		pt_entry_t *ptep;
3222
3223		if (curproc && curproc->p_vmspace) {
3224			ptep = pmap_pte(&curproc->p_vmspace->vm_pmap, va);
3225			if (ptep)
3226				pa = mips_tlbpfn_to_paddr(*ptep) |
3227				    (va & PAGE_MASK);
3228		}
3229	} else if (va >= MIPS_CACHED_MEMORY_ADDR &&
3230	    va < MIPS_UNCACHED_MEMORY_ADDR)
3231		pa = MIPS_CACHED_TO_PHYS(va);
3232	else if (va >= MIPS_UNCACHED_MEMORY_ADDR &&
3233	    va < MIPS_KSEG2_START)
3234		pa = MIPS_UNCACHED_TO_PHYS(va);
3235#ifdef VM_ALLOC_WIRED_TLB_PG_POOL
3236	else if (need_wired_tlb_page_pool && ((va >= VM_MIN_KERNEL_ADDRESS) &&
3237	    (va < (VM_MIN_KERNEL_ADDRESS + VM_KERNEL_ALLOC_OFFSET))))
3238		pa = MIPS_CACHED_TO_PHYS(va);
3239#endif
3240	else if (va >= MIPS_KSEG2_START && va < VM_MAX_KERNEL_ADDRESS) {
3241		pt_entry_t *ptep;
3242
3243		if (kernel_pmap) {
3244			if (va >= (vm_offset_t)virtual_sys_start) {
3245				/* Its inside the virtual address range */
3246				ptep = pmap_pte(kernel_pmap, va);
3247				if (ptep)
3248					pa = mips_tlbpfn_to_paddr(*ptep) |
3249					    (va & PAGE_MASK);
3250			} else {
3251				int i;
3252
3253				/*
3254				 * its inside the special mapping area, I
3255				 * don't think this should happen, but if it
3256				 * does I want it toa all work right :-)
3257				 * Note if it does happen, we assume the
3258				 * caller has the lock? FIXME, this needs to
3259				 * be checked FIXEM - RRS.
3260				 */
3261				for (i = 0; i < MAXCPU; i++) {
3262					if ((sysmap_lmem[i].valid1) && ((vm_offset_t)sysmap_lmem[i].CADDR1 == va)) {
3263						pa = mips_tlbpfn_to_paddr(sysmap_lmem[i].CMAP1);
3264						break;
3265					}
3266					if ((sysmap_lmem[i].valid2) && ((vm_offset_t)sysmap_lmem[i].CADDR2 == va)) {
3267						pa = mips_tlbpfn_to_paddr(sysmap_lmem[i].CMAP2);
3268						break;
3269					}
3270				}
3271			}
3272		}
3273	}
3274	return pa;
3275}
3276